recipe for target failed openjdk1.8

Question: When I compile openjdk 1.8 using this command:
make images

Throw this error:
cc1: warning: command line option '-std=gnu++98' is valid for C++/ObjC++ but not for C
/Users/dolphin/source/dabai/openjdk8-dev/hotspot/make/bsd/makefiles/saproc.make:123: recipe for target 'libsaproc.dylib' failed
make[6]: *** [libsaproc.dylib] Error 1
make[6]: *** Waiting for unfinished jobs....
/Users/dolphin/source/dabai/openjdk8-dev/hotspot/make/bsd/makefiles/top.make:128: recipe for target 'the_vm' failed
make[5]: *** [the_vm] Error 2
/Users/dolphin/source/dabai/openjdk8-dev/hotspot/make/bsd/Makefile:290: recipe for target 'debug' failed
make[4]: *** [debug] Error 2
Makefile:230: recipe for target 'generic_build2' failed
make[3]: *** [generic_build2] Error 2
Makefile:177: recipe for target 'debug' failed
make[2]: *** [debug] Error 2
HotspotWrapper.gmk:44: recipe for target '/Users/dolphin/source/dabai/openjdk8-dev/build/macosx-x86_64-normal-server-slowdebug/hotspot/_hotspot.timestamp' failed
make[1]: *** [/Users/dolphin/source/dabai/openjdk8-dev/build/macosx-x86_64-normal-server-slowdebug/hotspot/_hotspot.timestamp] Error 2
/Users/dolphin/source/dabai/openjdk8-dev//make/Main.gmk:109: recipe for target 'hotspot-only' failed
make: *** [hotspot-only] Error 2

OS: Mac OS Mojave
gcc version 6.5.0 (Homebrew GCC 6.5.0_2)
Makefile:
#
# Copyright (c) 2012, 2013, Oracle and/or its affiliates. All rights reserved.
# DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
#
# This code is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License version 2 only, as
# published by the Free Software Foundation.  Oracle designates this
# particular file as subject to the "Classpath" exception as provided
# by Oracle in the LICENSE file that accompanied this code.
#
# This code is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
# version 2 for more details (a copy is included in the LICENSE file that
# accompanied this code).
#
# You should have received a copy of the GNU General Public License version
# 2 along with this work; if not, write to the Free Software Foundation,
# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
#
# Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
# or visit www.oracle.com if you need additional information or have any
# questions.
#

# This must be the first rule
default:

# Inclusion of this pseudo-target will cause make to execute this file
# serially, regardless of -j. Recursively called makefiles will not be
# affected, however. This is required for correct dependency management.
.NOTPARALLEL:

# The shell code below will be executed on /usr/ccs/bin/make on Solaris, but not in GNU make.
# /usr/ccs/bin/make lacks basically every other flow control mechanism.
TEST_FOR_NON_GNUMAKE:sh=echo You are not using GNU make/gmake, this is a requirement. Check your path. 1>&2 && exit 1

# Assume we have GNU make, but check version.
ifeq ($(strip $(foreach v, 3.81% 3.82% 4.%, $(filter $v, $(MAKE_VERSION)))), )
  $(error This version of GNU Make is too low ($(MAKE_VERSION)). Check your path, or upgrade to 3.81 or newer.)
endif

# Locate this Makefile
ifeq ($(filter /%,$(lastword $(MAKEFILE_LIST))),)
  makefile_path:=$(CURDIR)/$(lastword $(MAKEFILE_LIST))
else
  makefile_path:=$(lastword $(MAKEFILE_LIST))
endif
root_dir:=$(dir $(makefile_path))

# ... and then we can include our helper functions
include $(root_dir)/make/MakeHelpers.gmk

$(eval $(call ParseLogLevel))
$(eval $(call ParseConfAndSpec))

# Now determine if we have zero, one or several configurations to build.
ifeq ($(SPEC),)
  # Since we got past ParseConfAndSpec, we must be building a global target. Do nothing.
else
  ifeq ($(words $(SPEC)),1)
    # We are building a single configuration. This is the normal case. Execute the Main.gmk file.
    include $(root_dir)/make/Main.gmk
  else
    # We are building multiple configurations.
    # First, find out the valid targets
    # Run the makefile with an arbitrary SPEC using -p -q (quiet dry-run and dump rules) to find
    # available PHONY targets. Use this list as valid targets to pass on to the repeated calls.
    all_phony_targets=$(filter-out $(global_targets), $(strip $(shell \
        cd $(root_dir) && $(MAKE) -p -q FRC SPEC=$(firstword $(SPEC)) | \
        grep ^.PHONY: | head -n 1 | cut -d " " -f 2-)))

    $(all_phony_targets):
    @$(foreach spec,$(SPEC),(cd $(root_dir) && $(MAKE) SPEC=$(spec) \
        $(VERBOSE) VERBOSE=$(VERBOSE) LOG_LEVEL=$(LOG_LEVEL) $@) &&) true

    .PHONY: $(all_phony_targets)

  endif
endif

# Here are "global" targets, i.e. targets that can be executed without specifying a single configuration.
# If you addd more global targets, please update the variable global_targets in MakeHelpers.

help:
    $(info )
    $(info OpenJDK Makefile help)
    $(info =====================)
    $(info )
    $(info Common make targets)
    $(info .  make [default]         # Compile all product in langtools, hotspot, jaxp, jaxws,)
    $(info .                         # corba and jdk)
    $(info .  make all               # Compile everything, all repos and images)
    $(info .  make images            # Create complete j2sdk and j2re images)
    $(info .  make docs              # Create javadocs)
    $(info .  make overlay-images    # Create limited images for sparc 64 bit platforms)
    $(info .  make profiles          # Create complete j2re compact profile images)
    $(info .  make bootcycle-images  # Build images twice, second time with newly build JDK)
    $(info .  make install           # Install the generated images locally)
    $(info .  make clean             # Remove all files generated by make, but not those)
    $(info .                         # generated by configure)
    $(info .  make dist-clean        # Remove all files, including configuration)
    $(info .  make help              # Give some help on using make)
    $(info .  make test              # Run tests, default is all tests (see TEST below))
    $(info )
    $(info Targets for specific components)
    $(info (Component is any of langtools, corba, jaxp, jaxws, hotspot, jdk, nashorn, images, overlay-images, docs or test))
    $(info .  make <component>       # Build <component> and everything it depends on. )
    $(info .  make <component>-only  # Build <component> only, without dependencies. This)
    $(info .                         # is faster but can result in incorrect build results!)
    $(info .  make clean-<component> # Remove files generated by make for <component>)
    $(info )
    $(info Useful make variables)
    $(info .  make CONF=             # Build all configurations (note, assignment is empty))
    $(info .  make CONF=<substring>  # Build the configuration(s) with a name matching)
    $(info .                         # <substring>)
    $(info )
    $(info .  make LOG=<loglevel>    # Change the log level from warn to <loglevel>)
    $(info .                         # Available log levels are:)
    $(info .                         # 'warn' (default), 'info', 'debug' and 'trace')
    $(info .                         # To see executed command lines, use LOG=debug)
    $(info )
    $(info .  make JOBS=<n>          # Run <n> parallel make jobs)
    $(info .                         # Note that -jN does not work as expected!)
    $(info )
    $(info .  make test TEST=<test>  # Only run the given test or tests, e.g.)
    $(info .                         # make test TEST="jdk_lang jdk_net")
    $(info )

.PHONY: help

Comment: Maybe https://github.com/manasthakur/jdk-tips/wiki/Building-OpenJDK-8-on-Mac-OS-X-Yosemite helps - it mentions that you should use an older xcode because it has an older GCC which is required (newer xcode uses llvm-clang).
Answer: The GNU version of make on Solaris is gmake. Try that instead of make.

recipe for target failed openjdk1.8


Validating pickup wiring

Question: I want to replace the pickups on my guitar with another set.
Is there a way of knowing if I wired the pickups correctly before putting on the strings ?
Answer: A really good check that it actually works is to use a tuning fork:
Have the guitar plugged in, tap the tuning fork and hold it near the pickup. You can hear the response on each pole piece, so this is a simple way to confirm operation. This won't confirm phase, so you could potentially wire one pickup of a humbucking pair out of phase (if you have one that gives you 4 connections)
Answer: Honestly, the question is a bit ambiguous because there are so many factors at play here, but there are a couple of simple pointers that I have:
First, purchase a good multi-meter that has a diode test mode. The diode test mode will sound a beep if the two points where you connect the red and black leads have a connection. This is specifically useful when troubleshooting buzzes, signal losses, and checking for cold solder joints. If you connect two points and you don't hear a beep, those legs are not connected. There are cases where this is expected, however--so quite possibly the most important factor here is understanding what your wiring should do. If you don't get that, don't even attempt to swap out the pickups--get someone who understands what you want to do it for you.
Next, purchase an alligator clip lead tester. These guys are useful for short circuiting a leg of your wiring to help identify cold solder joints. Simply clip one end of the alligator to a pickup lead, and the other to a sweeper pole on a pot, or directly to output. There are a multitude of questions on this site related to troubleshooting miscellaneous wiring problems. Surf around and learn some things.
Wiring a guitar correctly, especially with more complicated circuits, is a complex beast rife with buzzes, hums, pops, and cracks. Typical problems include ground loops, improper grounding, and cold solder joints--which are all user errors. If you have experience soldering and building circuits then you'll be fine, but if this is your first try I recommend taking your work to someone who can check it out for you. If you don't have anyone, you can experiment until you get it right and be sure to arm yourself with lots of information.

Seymour Duncan Guitar Wiring 101
Lollar Guitars General Info
Lollar Guitars Mini-Humbucker Installation Video
Stewart McDonald General Info
Answer: Get a multimeter => http://www.ehow.com/how_6246347_test-electric-guitar-pickup-resistance.html
And once plugged in, if you have excessive noise with no reason, check that everything is actually grounded.
Answer: Ever heard of a guitarist who uses a "massager" as a special effect for a sound? Or the toy ray gun that Steve Stevens used on Billy Idol's "Rebel Yell"? Pickups pick up more than strings. So, put a zapper (while pressing a button) or a ray gun or a ... well ... over the pickups as you go through your switches. If the sound goes through, you wired it right.

Validating pickup wiring


What are the key strategy differences between Settlers of Catan and Seafarers?

Question: Just starting out with Seafarers of Catan—what are the key strategy differences between Settlers of Catan and Seafarers?
Comment: After trying Cities and Knights, all other expansions dissapoint...
Answer: For me the big strategy for seafarers is to realize that most of the time the islands are not worth it.  If it is very convenient to go for an island then do it, but usually I find that the resources I expend could have been better used elsewhere.
(Though if everyone is following this strategy, then the islands are great because of the free space.  Basically you want everyone else to go for the islands but you.)
Comment: I disagree.  Whether the islands are worth it or not is map and resource dependent.  Most of the maps are too cramped on the starting island to win without expanding.
Answer: When placing 1st or 2nd in the basic game, I always look at the board and determine which of the two basic strategies (ore/hay & wood/brick) works best.  If I place 3rd or 4th, and my opponents know what they are doing, I often have to use the opposite strategy (or one of the others i.e. balanced/monopoly/etc).
Seafarers adds wood/sheep as a third equally viable strategy.  I enjoy this since it gives you more options when placing 3rd or 4th.  Since both wood/sheep are needed for boats, players with higher probability wood/sheep hexes will be more able to explore.  Don't under value the 2 bonus points for building on an island.  Unlike longest road and largest army, you can't lose these points.
One key difference to the wood/sheep strategy in seafarers is that it is a two-part strategy.  Building towards a high-probability outer island hex allows you to make-up for a lack of that resource on the main island.  In this way, you almost shift strategies mid-game.
My first choice is to build towards a good Gold hex.  You can do anything with it.
My second choice is to build towards a good hay or ore hex.  Both allow you upgrade your cities and free up settlement tokens for further expansion.  Good access to sheep/hay/ore also allows you to hoard development cards and go for largest army & victory point cards. (If you are using the wood/sheep strategy, I assume you already have good access to wool.)
If I don't have good access to brick on the mainland, building towards brick helps to build settlements without having to trade-in, and also to go for longest road.
Answer: To me, the big benefit of playing Seafarers is the diversity of maps, and the ability to play random maps.  I find the default random map is a little sparse on land, but this only makes you think harder on where you want to build.  These new maps open up new strategies, and change the dynamic of land settlement from being contained on a single land mass.  Depending on the map and the starting positions, you could want to focus on boats or completely ignore them.  As said above, you might want to strike out visit new land in order to get more victory points.
Depending on what scenario your playing, and what the map looks like, changes how you play.  Seafarers games take longer, but if your playing random maps, it makes each new game different.
There is also the discovery map, where you never know what tile your uncover next.
Answer: You need sheeps and wood to build a ship, so sheep are slightly more important.
Second, most games give extra victory points for the first settlement on a new island. This can be nice, but realise that you will have at least two settlements on a coast, reducing the number of goods for them.
Answer: In my experience, small islands are usually not worth going for in the beginning of the game because the amount of territory you get access to is not worth the resource requirements. Obviously, the larger the island, the closer it is to your starting position, and the more dots worth of production, then the more worth while it is to go for.
However, even if you don't settle any islands for the first 80% of your game, there are two big strategy changes:
1) Ships can be moved (1 per turn). Building many ships can be a strategic choice that offers many tactical advantages during the game:

It is possible to build an additional settlement without needing to first build
a road or ship, by relocating a ship.
In basic Settlers it can be very risky to go for a settlement site when
there's competition, as you may end up with 2 or more stranded and
useless road links. Now if you compete with ships to a coastal site,
you can relocate them if you lose a race.
You can do tricky things with getting longest road.
In scenarios where resources are earned for island exploration, you
can move your ships around to keep getting more resources, then
relocate them to their final destination later.

With ships opening up so many more opportunities, wood and sheep are more valuable in Seafarers than in Settlers.
2) The bonus victory point(s) offered in many scenarios for building your first island settlement makes for an interesting end game strategy not available in basic settlers. As discussed in What is optimal end play in Settlers?, it can be hard to win Settlers by increasing one victory point at a time, as players gang up to slow the leader. In Seafarers, islands make it possible to catapult to victory with a 4-6 victory point turn. You do this by waiting to settle your first island on the turn you think you can win because you have the right combination of resource and development cards, as follows:

play a key development card (Monopoly? Year of Plenty? Road
Building?)
move a ship
build more ships/roads until you have longest road (2 victory points)
build a settlement on the island (2-3 victory points)
add in your developments cards that are victory points (0 or more
points)

Building your first settlement on an island counts for 1 victory point for the settlement, and 1-2 bonus points depending on the scenario and the edition of Settlers of Catan edition you're using. Older editions have a 1 victory point bonus, while the newest edition usually offers a 2 victory point bonus.
About gold: In most games I've played, islands with gold usually take a lot of resources to reach and then attract the robber disproportionately. So going for gold is rarely a winning strategy.


Can Gauss sums derandomize any heuristic arguments?

Question: I've always been fascinated by the fact that the classical Gauss sum has absolute value $\sqrt p$, which is exactly what we would expect if we were to interpret the Gauss sum as a random walk.  In particular, I have long wondered whether this apparent link between number theory and probability theory is just a curiosity, or whether it is a symptom of a deeper connection.  For example, there are many heuristic arguments in number theory that treat primes as being "random."  Is there any example of such a heuristic argument that can be made rigorous by using the above observation about Gauss sums?
Comment: I wouldn't expect exactly $\sqrt{p}$, and the expectation of the absolute value of the random walk isn't $\sqrt{p}$. The expectation of the square of a random walk (with $p$ unit steps) is $p$, but the square of the expectation is not the expectation of the square.
Comment: Speaking solely for myself, what I would expect if I were to interpret the (quadratic) Gauss sum as a random walk is that most of the time its absolute value would be pretty close to $\sqrt p$; I would not expect it to be, as it is, exactly $\sqrt p$ all the time. Higher order Gauss sums are maybe closer to what I'd expect of a random walk (I'm not sure if that makes them better or worse candidates for the sort of application you have in mind).
Answer: The thing is that it is well known that for the quadratic Gauss sums, expressed as an exponential sum rather than with Legendre symbols, the path is very much not a random walk when you plot it in the complex plane. There is plenty of structure visible as approximate Cornu spirals.
Such sums are not the only Gauss sums, as I know to my cost; and the quadratic case is atypical (perhaps). But from a high-flown point of view, a Gauss sum is a special function in the theory of finite fields (like a Gamma function). There seems to be more mileage in asking about what is special about it.
Answer: Caveat lector: as an answer to Timothy's question, this is tangential at best.
Regarding Gerry and Kevin's comments, people might be interested in Section 2 of these notes of mine
from an undergraduate number theory course, in which the philosophy of "almost square root error" is batted around for a while, especially with regard to the Riemann hypothesis.  This is maybe my favorite set of lecture notes from this course, perhaps because I got a chance to (talk and) write excitedly about things I hardly understand: I certainly do not claim a professional level of insight here.  (Indeed some regulars on this site could do far better, and I would be interested to hear their critiques.)
The upshot though is that of agreement with Gerry and Kevin: having size $\sqrt{p}$ on the nose is just a little bit better than random, but the little bit makes a big difference: to me this suggests very precise structure rather than randomness.
Please see here for another take on the subject of almost square root error in the context of the Sato-Tate Conjecture.  This latter article was written at almost the same time as mine, and the author happens to be my former thesis advisor.  I am reasonably sure that both of these coincidences are indeed coincidental.
Comment: At the start of Section 1.3 of the notes which you link to, you write that Riemann used the notation $\sigma + it$ for complex variables in his paper on the zeta-function. He never used $\sigma$. In fact the only complex numbers whose real and imaginary parts he wrote out were on the line with real part 1/2.
Comment: The notes ae no longer in the link, but they say to go to another link for the notes. That other link is also not functioning.
Answer: Actually I would think there are connections. Even if the the coincidence $\sqrt{p}$ seems ordinary, there are low-correlation sequences which owe their low correlation to Gauss sum estimates and looking from a probabilistic view point sequences, I would think there would be interpretations from a view point of uncorrelated random variables. Your starting point could be low-correlation sequences used in communications systems and beyond that I would think Nicholas Katz and Sarnak's dive into random matrices would help.
http://books.google.com/books?id=wXyOPbzvowsC&printsec=frontcover&dq=inauthor:%22Nicholas+M.+Katz%22&hl=en&ei=j9IrTu24CpKnsAKG5c3DCw&sa=X&oi=book_result&ct=result&resnum=5&ved=0CD8Q6AEwBA#v=onepage&q&f=false


Is Base64(SHA1(GUID)) still unique like the original GUID?

Question: Basically what the title is; GUIDs are unique by design. If you run the GUID through SHA1 and then Base64 the hash, will the resulting string have the same guaranteed uniqueness as the GUID, or not?
Answer: Base64 provides a 1:1 transform from input to output (and back again if desired). So if you take a set of unique items and base64 encode all of them they will all be unique.
So the question becomes if you run a GUID through SHA1, will the resulting hash have the same uniqueness as the GUID?
The answer is practically - yes; theoretically not quite. Multiple inputs to SHA1 map to the same output, but in reality if your GUIDs are unique then there is negligible probability that there will ever be a collision leading to loss of uniqueness.
Answer: Assuming no cosmetics, the length of a GUID is 32 bytes so better question would be "What's the collision probability of SHA1 with 32 bytes of input?"
I'm sure someone else will answer with the exact statistics but the answer to your question is yes, it's pretty unique (an attacker has a negligible probability of success). Note that I've completely ignored Base64 because it is reversible.
Edit: This question can provide some more insight
Comment: The length of a GUID is 16 bytes. You can encode these bytes as a 32 byte hex string.
Answer: First note that GUIDs are not absolutely guaranteed to be unique. The early GUID constructions were supposed to be deterministically unique but this relied on clocks moving monotonically forwards and MAC addresses being deterministically unique. Later GUID versions gave up the deterministic uniqueness completely.
It is possible that two distinct GUIDs could hash to the same SHA1 hash but the chances of that happening in practice are much lower than the chances of a uniqueness failure of the underlying GUID generation system.


How to generate Templates with Apples Pages?

Question: I want to create a template, which is conform to the German business style DIN 676. Somehow I can't figure out how to achieve this. Is there a good Documentation for creating templates within pages?
Answer: Are you asking how to turn an existing document into a template, or are you needing advise on how to make the document?
If it's the former, you just need to save your document as a template using quite simply File > Save as template.
If it's the latter, then judging by the link you mentioned, I would start with a blank document in page layout format.  Select View > Show Layout and Show Rulers.  Start with your page margins, and set them to that shown in your example.  Then add text boxes that you can size and align against the rulers to make sure that they are in the correct places for the addresses etc.  For the section under the address that is 5 columns, you could use a table, using the cell properties to ensure the middle column is the desired width.
I can't read German, so am unsure what a lot of the notes mean, but I hope this is a start for you.
Comment: @stuffle, exactly what I needed. I did not know, that those fields are generated by "Layouts". Thank you!
Comment: No problem :)  Anything else, just ask.
Answer: There are easily 10 articles showing you the mechanics of preparing a document to become a template, creating custom placeholders in a template and much more at Apple's support site.
Just Search  pages custom template


Can a ceiling light shade be replaced? Where can I find a replacement?

Question: The shade of a ceiling light in my apartment cracked and fell on the floor.  I started looking around on the web to see if I can buy a replacement but I'm having difficulty finding anything.  Can this be done, or does one normally have to replace the whole fixture?  It's  a circular fixture, about 8 1/4 diameter - three screws in the sides secure the shade to the fixture.  If the fixture has to be replaced, I'll have the superintendent of our building do it, as the apartment is a rental.
Answer: For the kind of light fixtures that you typically get in apartments (i.e. not terribly nice), you could look in the big-box stores.  If you're in the US, I know Lowe's has a selection of them (though admittedly not a huge one).
If you can't find one there, look for a specialty lighting store, where you should be able to find a much wider selection.
Answer: The type of shade you're looking for is fairly common, but it's not common for non-specialty shops to carry them.  On top of that, the cost of a replacement shade, if you do manage to find one, can often approach or surpass the cost of a brand new fixture!
My suggestion would be to do a quick check at the big box hardware stores and the lighting specialty shops just on the off chance that they DO carry the replacement glass.  Unless you don't put any value on your own time, going beyond that isn't going to be worth it.  A replacement light fixture in the style you describe is going to be in the $10 to $20 dollar range.  I've even seen twin packs with bulbs for under $20 on special.
Comment: I wound up buying a replacement fixture for $14.95 and using the shade from that.
Answer: Depending on your location (whereabouts in the world), either a "general" High Street DIY store will sell just shades in their light fitting department, eg in the USA

Lowes
Homedeopt

Or if the shade is more a non-standard affair, a specialist High Street Light shop might be your better option.
Either way, you can most definitely buy just a shade for a light fixture.
Answer: To add to previous answers, you may be stuck with an old style depending on the age of your building. Try looking for a shade first, but you may have to go with plan B.


How can I gank effectively as Jungle Skarner?

Question: I like Skarner, a lot. But despite that, I don't understand him entirely to be honest. He has an amazingly short range, no proper initiate skill, and his CC is his ultimate. To even get his slow off you have to hit with it twice before it works. How can he jungle effectively without any kind of ability to properly gank?
Answer: First of all, the simplest part of your post to deal with is his Crystalline Slash.  You're correct that you need to hit it twice in order to generate the slow debuff.  You do NOT have to hit it twice on the enemy champion.  As you run towards your gank target, hit Crystalline Slash once when it range of enemy creeps.  This way, when you Crystalline Slash the enemy, you are immediately slowing.
Second, Skarner is all about the ability to quickly get on your target, since all of his abilities require being in so close. Start off by using the increased movement speed quints and putting 4 points in Swiftness.  With these, plus boots 1, you will be at 405 move speed.  When your Crystalline Exoskeleton is active, you'll jump all the way up to 452 move speed.
Finally, when ganking, pay attention to where you are coming from.  Often you want to be moving from behind the enemy in lane. If you come out in front of them, or from the wrong side if you're ganking middle, then they can retreat in a straight line making their escape significantly simpler.
If you want to watch a pro play Skarner and learn from them, look up Diamondprox.  He's the jungler on Moscow 5, an elite LOL competitive team.
Answer: One of the absolutely most clutch things you need as Skarner is flash. You dont really wanna gank without it. That is, post-six.
Answer: A good Skarner is a terror to behold. His movespeed steroid, slow, and boosted armor (as well as his pull when he hits six) make for some ridiculous ganks even if you don't coordinate with your teammates. He's a top-tier jungler for a reason; his ganks kick ass! I don't mean to be presumptuous, but he does have a rather high skillcap and if you don't build him properly/take the correct skill order/use his skills at just the right time...he's going to fall short of your expectations. :P
I'd recommend this guide, my friend's Skarner game has improved a great deal since he started following it. The most important tip in there is to remember to autoattack as much as possible to keep your cooldowns lower, making it much easier to land your Q for a second time and get the slow off.
Answer: Even at low levels, his Q combined with a blue ( and/or red buff ) is basically a permanent slow. If you see an overextended enemy, W into lane and use your initial Q on a minion to gain the slow proc on it.
Post-6, all you need is either flash or a Shurelya's. For extra slows, a Rylai's is always nice, of course. Combined with the slow from his Q, enemies are made almost immobile.


What are the pros and cons of a cultured marble tub?

Question: I'm in the middle of a bathroom remodel (tear-out done), and the next step is to choose a tub. From a materials perspective, what are the pros and cons of using a cultured marble tub? For instance, resistance to scratching and chipping, noise, color-fastness over time, etc.
Answer: I have a cultured marble kitchen sink so I guess my experience is relevant. It is noiseless (unlike a stainless steel one would), looks as cools as a stealth bomber (much cooler that a stainless steel one would), can be washed no-problem.
Surely there're drawbacks - I always fear dropping a heavy fryinng pan onto it and crash it this way and obviously I remember to never use any acid-based compounds on it. IMO acid-based compounds can be easily avoided and fear of crashing is mostly subjective - likely something heavy needs to be dropped from a reasonable height to cause real damage. Other than that  I don't see any drawbacks so far.
Answer: I'll defer to the experts, but in the meantime, this link may be helpful in describing the basic pros and cons of the various tub options (scroll down the page to see the pro/con breakdown). From what I could find, the material itself is quite resilient against damage, mold, and color fading.  That being said, the largest objection has been personal preference as some people consider cultured marble to look "dated".
-M
Comment: Thanks for the info. We ended up purchasing one that is all white, which (IMO) does wonders to eliminate the "dated" appearance that cultured marble typically has (and I know exactly what you mean - most of the colors available scream late '80s to me).
Answer: Just a note for anyone who stumbles across this question in the future: my research turned up several reports that cultured marble should not be cleaned with any type of abrasive cleaner (i.e. Comet or other common "bathroom" cleaners). It is a relatively soft material, and will scratch more easily than acrylic, porcelain, etc. However, scratches can also be polished out.


How many visitors (percentage) click the main category of a multi-level navigation menu (e.g. About Us) and how many select a sub-level?

Question: I'm curious what people instinctively do and whether anyone has data on it.  When I go to About Us, for example, I click on it rather than on a sub-lelvel, which usually has "Meet the Team," etc.
Answer: Our analytics and heatmaps show that users go straight for the "main category" link more than I would expect, but then, I designed the dropdowns and interactions, so my expectations are a little biased.
It's not exactly hard data, but I've generally seen that of all the clicks garnered within a menu section (a main category link and sub category links in the related dropdown) the main link is responsible for 20-30%, with the rest of the clicks distributed among the other links.
That said, there are several factors that might affect this:
The Label
Verb-based labels see more direct clicks on the main links that more passive descriptions. The top level link that's clicked directly most often is "Contact Us", much more than labels like "Company" and "Solutions". (though this could also be a result of the users expectations being set by convention)
This is speculation, but I'd bet that in an A/B test between the labels "Products" and "View Products", the latter would see more direct clicks.
The Interaction/Implementation
The speed and type of interaction on your menu will play a factor. If your dropdown doesn't snap into place quickly, or the interaction is clunky, non-conventional, or generally dissatisfying, your top level links will probably end up with more clicks.
The Device
We've run into issues with mobile devices where we hadn't built in touch-to-hover functionality. So anywhere an interaction was on hover, like the main menu dropdowns, the user only had the option of the top level link.
What to do?
I think that unless you're going to build the menu such that the function of the top level links is merely to display the dropdown, then your focus should be on those main category landing pages, and on making sure they're well designed and fulfill their function of moving traffic to deeper pages.


How to set facebook page order

Question: I have a facebook page where I want to add an app as a page. In the old version you could drag'n'drop the tab order, but now I can't find any way to change the order of the pages.
This is my test page: http://www.facebook.com/pages/edit/?id=192515850771209&sk=featured#!/pages/Mtest/192515850771209
The page with the red "M" is my app that I want to be able to set the order where it appears in the list.
Thanks,
Rob
Answer: Just under the list is an edit button - click on it - drag and drop in the order you desire.
Answer: Remove all the apps and add them back in the order you want them to appear.

How to set facebook page order


Tagging users in Wordpress

Question: I have a community blog at thelazy.info . I want to tag users based on their colleges and assign a role known as "College Owner" which will have permissions to edit users belonging to his colleges. How can I go about it?
Answer: Wordpress has no multi-level user and group ownerships / permissions by default. So what you are asking for you need to implement on your own by extending the database and the program.
You can then fine-grained control what users are allowed to do and what not. Like Zack suggested, this can be combined with custom user profile fields, but you can do anything you like with a system of your own.
Answer: You might want to check out the following article. I think it's what you want.

Adding and using custom user profile fields
Answer: You can tag users using the get/add_option function; each option is concidered a tag and its value is the users id's array
Answer: For tagging you can use the User Tags Plugin, while for managing the users forsame tag, you have to go for a custom script, the plugin will make it easier as it uses WordPress taxonomy for tagging

Tagging users in Wordpress


Determine if List View is either builtin or custom

Question: What is the safest way to determine if a list view is either builtin (came with Sharepoint by default) or custom (created by a user) ?
Answer: Most lists only come with an All Items view, but it depends on what type of list it is.  You can open the site in SharePoint Designer and look at the list forms.  The AllItems.aspx (or whatever the default forms are for that list type) will have a date/time stamp from when the list was created.  Any other aspx pages will be either forms for the list (DispForm, NewForm, EditForm) or additional forms. The date/time stamps on those pages ought to tell you when they were created.  If the date/time doesn't match the AllItems.aspx page, then it's highly likely that the views were created by a user.
Answer: You could look in the 12/Template/Features directories for the List Template feature matching the list in question and compare it to the schema.xml's declared views. I'm not sure if any OOTB views are created programmatically by built-in features, so this is probably not the 'safest' way.
I didn't see a way to determine this via the UI or SharePoint Manager 2007.


Background reading on using GPUs for GIS?

Question: I'm interested in the emerging intersection between GIS systems and GPUs, which can provide orders of magnitude improvement to certain classes of GIS problems. Do you know of any good resources discussing this area?
Answer: Good question. While http://gpgpu.org is a good resource, it is quite general (the first G stands for General, after all).  Searching there for GIS I get only one hit from 2004, which links to a paper that is 404.
Manifold is the only vendor I'm aware of leveraging the GPU for GIS.
Hoopoe sure looks interesting, which also administers CUDA.NET.
Answer: Part of the ESRI Applications Prototype Lab's DevSummit presentation was on GPU for GIS.
The video link appears to be borked, but a lengthy blog post contains a good summary and introduction to GPU computing wrt GIS.
Also, Azavea (formerly Avencia) has won some NSF grants to investigate this area further, and they have a series of blog posts that appear to be regularly updated (last post July 7th)
Answer: I've been using Manifold GIS for years, and though at times a target of derision for a variety of reasons, the software is quite impressive. The current version (8.0.18 at time of writing) uses CUDA to accelerate surface operations 100x or so.
The long awaited version 9 promises to both improve on that level of acceleration and to broaden the scope of its impact. There is an interesting webcast viewable on the Nvidia site regarding what Manifold has done and where they are going (here). The are very much at the forefront of this technology whether applied to GIS or not.
More bonus points: native 64 bit capability and versions ranging from $250-ish to under $1000
Even if all you do is raster processing it pays for itself in a few hours.
Answer: There is some experimental work for porting parts of GDAL to use GPU, via OpenCL.  See, for progress, this recent email.
The source-code might be instructive.
Answer: A starter keyword for you is GPGPU. You can snag a book on GLSL or HLSL which are the respective languages/platforms for OpenGL and DirectX. You could use proprietary computing platforms like Nvidia CUDA or AMD CTM. But if you want a hint of sanity you may want to check out the somewhat new OpenCL standards.


Should steeping grains be crushed differently than mashing grains?

Question: Looking at the process for steeping grains I see that it omits a vorlauf.  Would crushing steeping grains in the same way as mashing grains produce too much fine particulate?  Should wort from steeping grains be filtered in a process like vorlauf (either in purpose or practice)?
Answer: When you steep your grains the main goal is to extract mainly color and flavor from the grain, a bonus of the process is you will get some starch conversion to sugar.  In order to extract the color and flavor the grain does need to be crushed in the same manor as an all grain mash.  I believe that due to the relatively small amount of specialty grains typically used that a vorlauf/sparge is not necessary and overkill for a pound of grain.  You can always reduce the amount of small particulates by shaking the steeping bag out before adding to the water.
Answer: And you should use the same amount of water for steeping as you would for mashing to avoid potential tannin extraction due to pH.  The grain has a natural tendency to reduce the pH of your water.  The darker the grain, the more it will drop pH.  pH, not temp, is the #1 culprit in tannin extraction, so if you use too much water the grain won't be able to overcome it.  You should steep using no more than 2 qt. water/lb. of grain.


How soon after mashing do I need to start my boil?

Question: I'd like to get 2 full boils from 1 mash.  Can I keep the 2nd runnings overnight for boiling the following day?  If so, what is the best way to store it.
In general, how long can wort be kept after mashing before it's boiled?
Comment: I don't see what's wrong with cooling as you would after boil and refrigerating overnight.  I can't imagine the yeasts/enzymes are going to do too much damage at 5°C.  Any reason why it would?
Answer: Short answer, a mash-out should be enough. Just hitting a boil is more than enough.
Mashing-out in this case would be key. You'll want to stop all enzymatic activity anyway, so that your wort is stable overnight. This consists of holding the wort at 170°F(76°C) for ten minutes.  Here's a pasteurization curve for milk.

(source: nzifst.org.nz)
On the UK standard, an additional 5°C equates to one order of magnitude reduction in the time necessary to kill.  That is, a pathogen that's killed at 69°C in one minute will die at 64°C in ten minutes.
HTST (high-temperature, short time) pasteurization for milk is conducted at 161°F(71°C) for 15-20 seconds. Mashing out happens at 170°F(76°C) for ten minutes. HTST pasteurization acheives a 5-log, or 99.999% reduction in pathogens.  By this math, in the first 15 seconds of your mash-out, you're killing ten times as many pathogens as milk pasteurization. If you extend your mash-out to fifteen minutes, you're applying 100 times the thermal killing power that we do to milk. (It should be said, though, that the point of milk pasteurization is to kill pathogens that might harm humans, not to kill bacteria that might contribute to off flavors. But a hundredfold increase is worth something.)
If you want to get in to the science of it, here's a paper on beer pasteurization, which gets into the survival of various bacteria, including Lactobacillus delbruckii.
People want something easy to remember. "Heat it to boiling and you're fine." But killing micro-organisms happens over a time-temperature curve, not at a particular temperature. That's why chefs who use the sous vide method of cooking are able to hold highly spoilage-prone materials like beef short rib at a pathogen-friendly 130°F for 36 hours(!) with no ill effects.  This kind of cooking gives the health inspectors the howling fantods, but it's not some sort of home-grown wisdom. It's science.
Short answer, a mash-out should be enough. Just hitting a boil is more than enough. In cooling down, you might generate some DMS, but it will be driven off when you re-boil it later.
Answer: You can, but baddies will be chowing down on your delicious sugary wort overnight.  I've heard of people using the brew in a bag method doing this though.
One thought would be to boil it for 15 minutes, put the lid on the kettle. I would think this would work well for a day or so.  If you can fit your whole kettle in an extra fridge this would help as well.
Some will get in there, but with a starter, the yeast will quickly overwhelm them with low pH and alchohol.
Answer: The guy at my homebrew shop was telling me that he mashes and lauters at night, then boils the next morning.
Billions of cells of yeast specifically bred for beer can take a couple days to start fermenting. Leaving it in a covered, sanitized container overnight and then boiling it for an hour seems like it would be fine.
Answer: If you can bring all the wort up to 185 or better yet just to a boil, you'll decrease the chance of some spoilage.
Grains are covered in spoiling bacteria and yeasts. The primary culprit is lactobacillus a souring bacteria.  So over time you may get a little bit of souring if you store the wort to long.
In the end, the short answer is to try it.  I have seen where several brewers try it and do it with success.  I am mildly dubious, but if it works it works.  Give it a try and then provide your own answer or an update in your question.
The cool thing is that you are making the same beer with the two collections then you can compare the overnight stored wort beer to the beer made "in process".  That may not be a bad idea for the first time you try it.
Good luck.
Answer: After looking at the pasteurization curve shown and seeing so many opinions I did some research as I wanted to know this answer. According to the chart, if you are conversion mashing at or above 150F/65C you have achieved pasteurization. Pasteurization is not sterilization which would be achieved at boiling for 10 min. Pasteurization goal is to reduce the number of viable pathogens just like all the sanitizing we do. Louis Pasteur developed the process for wine and beer and his range was 50-60C. His goal was to kills most of the bugs without affecting taste. Should store in sealed sanitized container. Refrigeration would not hurt. The most common milk pasteurized process the milk is held at 72C for 15 seconds.


Question Regarding Bootcamp and Windows 7

Question: I am possible going to install windows 7 on my iMac using the standard bootcamp setup and have a question about this setup.
I will store all of my large movies on the mac and will need good access to them, once windows 7 has been installed is it able to access HFS+ partitions at a reasonable speed and more importantly, will i be able to create an SMB share of the folders on the mac through windows?
Thanks for any feedback.
Answer: I recently installed Windows 7 using BootCamp on my MacBook Pro, Yes, I am able to access all the files on my mac HD.


Why do people paint some tree trunks white at the bottom?

Question: I've seen trees with the lower trunks painted white in a number of places around the world but have never found a definite answer to why this is done. Some suggestions that I've heard are to make them more visible at night time so people don't walk into them. Another is to make it easier for birds to see bugs on the trunk. Does anybody know why you would paint part of a tree white? What type of paint you would use? And why that paint doesn't damage the tree?
Comment: Interesting question. I've also seen some tree painted white but wonder why.
Comment: This link I found from google cover many reasons. http://www.ehow.com/about_5415717_do-paint-bottom-trees-white.html
Comment: @lamwaiman1988, why don't you put this in an answer?
Answer: In "The Garden Primer" (Damrosch), p 422:

Apple borers can also kill the tree outright just by tenneling in through the trunk [...] Painting the trunk with white latex paint diluted to 50 percent will make it easier to spot the sawdust residue produced by the larvae's tunneling.

Similar advice is in the Fedco Trees catalog; they suggest mixing white latex paint with joint compound.
Also in "Primer" on p 659:

Another danger to the trunk in winter is sun scald [...]. You can protect younger trunks from winter sun and wind by wrapping them in burlap or painting the trunks with white paint.

This same advice is repeated in "The Backyard Orchardist" (Otto), p43. She actually says to paint not only the trunk, but scaffolds out to nine inches from the trunk.
I'm pretty sure I've seen a mixture of something involving white latex paint to apply to the trunk that is supposed to deter four-legged pests. (I want to say that the recipe had sand in it so that any deer/rodent tasting the bark would get an unpleasant mouth feeling and would avoid the tree, but I can't put my hands on a reference right now. I don't think bone sauce would show up as white.)
Answer: when trees are painted white from bottom up to a certain level of the trunk it is called white washing or winter washing. the practice is most common in countries where real winters occur but not exclusively there. it's an effective method of reducing reinfestation of borers etc that either hide in trunk bark to overwinter or overwintering in soil to crawl up the tree in spring. also assists a little against secondary fungal infection of trunk by insect or other primary injury. what is this space age paint substance? lime mixed with a bit of water. it's done mostly on fruit trees but also on ornamentals such as hard and expensive to replace rows of street trees in cities.
Answer: I've seen this a lot in Arizona and other southwestern states in the US. Mostly the white paint is on citrus trees. The white paint protects the young citrus plants from the sun, when their bark is still thin. Eventually the canopy of the leaves means that the white paint is unnecessary but some people will continue to paint them because they like the way it looks.
Here in Boston I've seen tree wraps (but I guess you could also use white paint) used on new tree plantings, I assume for a similar purpose and also to prevent winter sun heating / winter evening freezing cycles.
Comment: I have five citrus trees in Phoenix, all painted, and sunscald is precisely the reason. I used a special "citrus paint", but in reality it was just diluted latex white paint.
Answer: I remember my Mom would 'white wash' our trees in Kentucky in the spring with a mixture of lime and water.  My brother and I would 'help.'  She told us it would keep the bugs away.  We had four maple trees in the front yard.  We did the same with the apple trees in the small orchard we had.  She would also use small pieces of lye soap and put them in the forks of the branches of some of the trees where she saw ants.  The white washed trees really looked pretty in the summer.
Answer: In (some parts of) Germany trees have a white markers (in form of stripes or a big rectangle) when they enclose a road ("Allee"). This is (or was) to avoid cars crashing into them and to save the plastic marker which usually helps to identify the road or the metal protection rail.
In other places I realized that trees which are painted or marked with color are to be felled. I saw that in woods (to clean) and in city (to make space :-( ).
Comment: We have similar thing in India. We use white markers to save road side trees.
Answer: Use a flat latex white  paint. helps keep the tree cooler and most bugs off the tree. I paint up to the y on citrus trees or other trees. You can get a paint called tree trunk white that preserves your citrus as well as other trees.
Answer: I have some trees in Bulgaria. I did nothing until I lost some apple trees to the bugs. But when my big walnut tree started going the same way I found out what locals painted their trees with. It's called 'slow lime' as opposed to 'quick lime' It contains calcium oxide and magnesium oxide plus a few other goodies. I've now painted all my trees and will see what the result is next year. I was advised not to use latex paint.
Answer: Here in Poland this is often done in late winter (February) to prevent sun scald.
Answer: I am from originally British Guiana (now Guyana) and this is an everyday thing in our country.
It is done simply for beautification! It makes the place look bright and beautiful.
Comment: Would you be able to add an example picture showing a typical painted tree of yours?
Answer: Bugs climbing up from the ground are better seen by birds and other bug eaters if they are on a white background. Bugs know this too and may avoid exposing themselves to predators.
Answer: The reason why trees are painted with white at the bottom is to prevent cracks, and if the bark of trees fell down there is a possibility of them getting infected with a virus.


Should I allow kernel updates?

Question: I am using Ubuntu 12.04 and the update manager appears daily with updates. I am ok with other updates but I want to know about Linux Kernel updates: Should I update to new versions, and why?
Answer: You can install any kernel you want. There is no problem on using one or multiple Kernels at a time. But sometime you should consider the Kernel Mapping to your Ubuntu Version. For example following link lists out the mapping of different kernel to different version of OS:
Ubuntu to Mainline kernel version mapping
You can get a complete information of Kernel installing/removing from following link.
Kernel Mainline Builds
It helped me a lot to install a new kernel in Ubuntu 12.04.2. Now I can chose any kernel 3.5.0 or 3.8.0 from grub menu.
Following link illustrates how Ubuntu 12.04 LTS works actually. It illustates in very nice way, you would also like:
Ubuntu LTS Enablement Stack
Hope this short description helps you.
Comment: this is no short description :)
Comment: @mojo706: ha ha ha.. You are right! I was talking about my short answer.. ;) Although to get such information, you have to read a lot of information.
Answer: The kernel manages the hardware of every Linux system and makes it available to the various processes.
Updating to a new Kernel keeps you up-to-date with Security Patches, Stability Improvements, Updated Drivers, and New Kernel Functions.
Answer: If you don't want something specifically from a newer Kernel, probably don't need to update. 99% of the time auto update is all you really need (unless you are fixing a particular problem).

Should I allow kernel updates?


How do I fix incorrect attic insulation?

Question: I have loose fill attic insulation. It seems to have been moved around and become compact. Is it just as easy as getting in there with a broom and 'fluffing' it up and moving it around, or do I need to just buy some new fill? Do I remove the old fill first if so?
Comment: I know it probably goes without saying but I thought I'd mention it anyway: 1) If the insulation is old, be sure to research whether or not it has asbestos in it.  Tests are cheap these days. 2) Be sure to ALWAYS use/wear sufficient safety equipment (e.g. eye protection, appropriate breather mask, gloves, etc).
Answer: I have some in my attic (from a previous owner) and I've found that it's never the same after it's been disturbed.  All that "fluffing" will do is create an enormous amount of dust.
I think you need to install new insulation; you shouldn't need to remove the old insulation if you're adding more of the same type.  The new will just sit on top of the old insulation.  If you do decide to remove some of the old, a shop-vac works well; just be ready for lots of dust.
Personally, I prefer fiberglass batting because you can move it out of the way if you need to, and it will spring back if you compress it.  These days, you can get batts that are sheathed in plastic so that they are clean and easy to install: no fiberglass dust!  Again, they would just sit on top of the existing insulation.
Answer: I recently had my attic insulated and was told that the blown-in insulation would settle and compact a bit over time.  So it may not be a problem for you.  I think "fluffing" it would get you nowhere.  You may want to instead have a home energy audit performed; with an IR camera, they can look at your ceiling and determine if there's insufficient insulation.


fundamental group and complete invariant of irreducible 3-manifolds

Question: I heard that,by Perelman's work,we can get that the fundamental group is a
complete invariant of irreducible 3-manifolds (except for lens spaces).
can someone help explain this.Thank you!
Answer: Perelman has proved Thurston's geometrization conjecture, which says that every irreducible 3-manifold decomposes along its canonical decomposition along tori into pieces, each admitting a geometric structure. A "geometric structure" is a nice riemannian metric, which is in particular complete and of finite volume.
There are eight geometric structures for 3 manifolds: three structures are the constant curvature ones (spherical, flat, hyperbolic), while the other 5 structures are some kind of mixing of low-dimensional structures (for instance, a surface $\Sigma$ of genus $2$ has a hyperbolic metric, and the three-manifold $\Sigma\times S^1$ has a mixed hyperbolic $\times S^1$ structure).
The funny thing is that geometrization conjecture was already proved by Thurston when the canonical decomposition is non-trivial, i.e. when there is at least one torus in it. In that case the manifold is a Haken manifold because it contains a surface whose fundamental group injects in the 3-manifold. Haken manifolds have been studied by Haken himself (of course) and by Waldhausen, who proved in 1968 that two Haken manifolds with isomorphic fundamental groups are in fact homeomorphic.
If the canonical decomposition of our irreducible manifold $M$ is empty, now we can state by Perelman's work that $M$ admits one of these 8 nice geometries. The manifolds belonging to 7 of these geometries are well-known and have been classified some decades ago (six of these geometries actually coincide with the well-known Seifert manifolds, classified by Seifert already in 1933). From the classification one can see that the only distinct manifolds with isomorphic fundamental groups are lens spaces (which belong to the elliptic geometry, since they have finite fundamental group).
The only un-classified geometry is the hyperbolic one. However, Mostow rigidity theorem says that two hyperbolic manifolds with isomorphic fundamental group are isometric, hence we are done. Some simple considerations also show that two manifolds belonging to distinct geometries have non-isomorphic fundamental groups.
Therefore now we know that the fundamental group is a complete invariant for irreducible 3-manifolds, except lens spaces.
Answer: An addendum to BM's answer: you might want to start with the Kneser-Milnor theorem which gives a unique decomposition of a 3-manifold as a connected sum and hence its fundamental group as a free product to reduce the question to prime (and then irreducible) 3-manifolds. The Poincare conjecture says you don't have any summands "hidden" from $\pi_1$.
Also, you have to be careful with what kind of 3-manifolds you consider, for example  if $F_1$ is a 3 punctured sphere and $F_2$ a punctured torus, then    $F_1\times S^1$ and $F_2\times S^1$ (or the complement of the square and granny knots for a more subtle example) have the same fundamental group but aren't homeomorphic.  So perhaps you want to first consider closed 3-manifolds. The issues for general compact 3-manifolds can get technical, but they are   understood. A good starting point is Hempel's book.
Comment: You also have to worry about orientation. In general M # N and M # $\overline{N}$ are not diffeomorphic.


Imaginary part of a spectrum

Question: Let $H$ be a Hilbert space, $A$ be a normal bounded operator on $H$ with spectrum $\sigma(A)=\{\lambda\in \mathbb{C}\;|\;A-\lambda Id \text{ is not invertible }\}$. Is $\sigma\left(\dfrac{A-A^*}{2i}\right)$ the set of imaginary part of the elements of $\sigma(A)$ ?
Thanks.
Answer: There is probably an elementary proof, but that's an immediate consequence of the continuous functional calculus :
$ \frac{A-A^*}{2i} = f (A) $
where $f$ is the imaginary part function on $\mathbb{C}$. And when you apply a continuous function $f$ to a normal operator $A$ you have : $Spec(f(A)) = f(Spec(A))$ (you can see that by restricting to the abelian sub-$C^*$-algebra generated by $A$).
Answer: The spectral theorme assert that there exist a unitary operator $U$ sucht that
$U^{*}AU$ is the multiplication operator by $\lambda$, $\lambda \in \mathbb{C}$. With the same unitary opeartor $U$, we have the real part (resp. the immaginary part) of $A$ mapped to $real(\lambda)$  resp. $imag(\lambda)$, with $real(A)=(1/2)(A+A^{*})$ and $imag(A)=(1/2i)(A-A^{*})$.
Comment: Though I also like to consider normal operators as multiplications, in what way is this answer different from the accepted one?
Comment: I think it is more elementary .

Imaginary part of a spectrum


How to create shortcut to insert specific special character

Question: I'm using some special characters like mathematical symbols in different programs like Mail or Adobe Illustrator. Of course I can open the Symbols Table, search for the needed symbol and copy&paste it. Is there a way to define a shortcut to insert a specific special character?
Answer: Two possibilities are through creating a modified keyboard layout (which can be done manually, but is made much simpler using a program like Ukulele) or through a shortcut program like TextExpander
I use TextExpander, myself, so that c== is a shortcut on my system for ⌘, o== for ⌥, and several others, in part because I do not want to lose the symbols already mapped to the option (⌥) key combinations on my keyboard.
On the other hand, remapping the ⌥ keys to symbols different than the ones they are original configured for can be helpful and convenient for some people also, which is where Ukulele shines.
Answer: You can use built-in Automator and Services. Look at my answer to the similar question.
Answer: You can get very fast access to the symbols via the widget CharacterPal.
Click on the needed icon in order to paste to the clipboard.
Comment: You mean copy to the clipboard?
Comment: And which icon?
Answer: Another option would be to create ~/Library/KeyBindings/ and save a property list like this as DefaultKeyBinding.dict:
{
    "\UF704" = { // F1
        "a" = (insertText:, "∀");
        "2" = (insertText:, "²");
    };
    "~a" = (insertText:, "∀");
}

After restarting applications, pressing F1A or  Alt ⌥  A should insert "∀".
Answer: You may create an AppleScript that insert your character.
Then, it is possible to have this script in the Scripts menu at the right.
Then I think that, in the menu, the script can have a keyboard command.
Then you are done!


Do I need to have played Mass Effect 1 or 2 to understand Mass Effect 3's storyline?

Question: I have never played Mass Effect 1 or 2.
Do I need to play the first and second installments to understand the third?
Are there enough story recaps to fill in some of the back story?
Will I be lost?
Comment: Tangentially related: http://gaming.stackexchange.com/questions/53662/will-playing-mass-effect-3-first-spoil-the-previous-games-in-the-series/
Comment: Tangentially related: http://gaming.stackexchange.com/questions/53647/is-there-a-good-synopsis-of-the-plot-of-mass-effect-1-2/53652#53652
Answer: This depends largely on what you want out of the game.
There is a long story interwoven between the three installments, and you'll certainly miss the depth  and some of the plot by not playing through all three and importing your character along the way. However the main plot arc is very linear throughout the series, and you won't be totally lost if you pick up ME3 completely ignorant.
However, Mass Effect 3 has some features that specifically tailor to new players. The game is well balanced and is completely playable if you haven't played ME1/2, but the biggest difference for certain users will be Action Mode.
Action Mode lets a player experience ME3 as a purely action and story based game, where there's no roleplaying or deciding; the game's story is set in stone, and you just watch. For players that just want to experience the action gameplay of Mass Effect without worrying about the story, Mass Effect 3 is probably the best game to play first.
Basically, if you really want the depth and roleplaying aspect, you'll be missing out if you start with Mass Effect 3, but it depends how much you care. If you want to play an action game, playing ME3 first is probably your best option.
Answer: There's a lot of backstory that you will likely miss out on, but Mass Effect 3's intro does a pretty good job of summarizing the main plot up until that point.  The wikia pages on Mass Effect's story and Mass Effect 2's story do a good job elaborating on all the events in each game.
Answer: As a new player to the series I've been able to jump in with both feet and enjoy the game.
Since the "I don't have a save file" character creation lets you artificially select some back story, I felt like I was getting an idea of who the main character was as if I'd played him through the first two games.
Additionally, while I've been a little confused on who the different races are and who the characters are, the game hasn't tried to shoehorn me into decisions that stem from earlier plot points (that I'm aware of :)
Answer: Playing through the first two provides a great sense of accomplishment in carrying your 'story' through the entire series.  Especially if some of the choices you prefer to have made might not be what the default options are in the game (most of them are paragon related).
However, each game is designed to be stand alone and you should not have issues picking them up separately.
Comment: Mass Effect has a morality scale similar to most of Bioware games. The scale is Renegade (bad) to Paragon (good). For reference to other Bioware games, think Dark side to Light side or Closed Fist to Open Palm.
Comment: What do you mean by "paragon related?"
Comment: @ahsteele for example, the assumption for me3 was you took the paragon choice at the end of me2
Answer: Main story wise, if you pick up Mass Effect 3 you'll understand what is happening mainly through dialogue and such, so you're fine there. Now side story wise, You would have to go back and play the previous games because there is just so much stuff, like characters and certain events that take place, that you just have to experience yourself. So long story short, you won't be lost main story wise but side story wise you might a little confused on who's who.
Answer: Personally, I got REALLY tired of driving around the Mako in Mass Effect 1.  The grinding in that game was not only incredibly boring but also incredibly time consuming.  I played about 2/3 of the game and then moved out of the country for a couple years.  When I came back and saw that a sequel was coming I wanted to finish the story without having to replay the whole game.
The solution I used was watching a fan-made theatrical cut of the game on Youtube.com...
Here: http://www.youtube.com/playlist?list=PL920E7AB26F3D2177
It's broken up in 23 parts and it's just the cut scenes, decisions and important parts of the action.  It saved me at least 50 hours I'm guessing.  Additionally, there are ME2 cut-ups too, but I have not seen any personally to be able to recommend them.
You won't be able to import a save this way, but at least you'll experience a greater depth of the story without have to spend 200 hours on 1 and 2.
Answer: I think Mass Effect 2 (ME) shows you how Sheperd saved the galaxy from collectors and the new cerberus organization.
In Mass Effect 3 the cerberus relationship continued in a rough manner, but we came close to the alliance (a human military organization) in game, just as we were in the first game as alliance military operative and we become a spectre in first and third game.
In my own words and analogy: It is going to feel like you wake up in the morning, do all your morning procedure and get ready for work. But you forgot to take breakfast (ME 1). Then it's your lunch time, and again, you forget to take lunch (ME 2). So you had no breakfast and no lunch. In the evening, with great hunger and thirst, you finally do the dinner to remove your hunger. Now look at dinner as it is ME 3, so this is totally incomplete that you can skip your meal of day time to time. so mass effect trilogy is same as meal which you should play equally all to achieve satisfaction and interest of getting out all three. In my opinion all three games of the series are good, much fun and let you  explore ME galaxy through out games. So remember: only playing ME 3 would be like leaving two important meals (breakfast and lunch) which would let your hunger explode to know more. Whenever you get chance you should definitely play all three games of the sequel.
Comment: great analogy but need to organize a bit
Comment: well in short it means that you should play them through in sequels to get the full satisfaction and you know it breakfast is the most important meal of the day :D
Answer: Having only played Mass Effect 1, I don't really feel like I missed out. Mass Effect 3 is obviously the third installment of this epic tale but there is enough summarizing and in-game journal entries and information to bring you into Mass Effect's world. That being said, there will certainly be some smaller details and potential "Ah ha!" moments that you might miss out on. It isn't like reading the last few pages of a good book or watching the last half-hour of a good movie. It is a complete game unto itself.
Answer: You will be able to play the 3rd with a general understanding of what's going on and find enjoyment in the game itself.
I'd argue that you would be robbing yourself of more enjoyment and would be missing the personal connection to the characters and fate of the story if you started on 3.
Regardless of what game you play first, I'd suggest playing 1 and 2 whenever you get the chance.


יוֹשְׁבֵי דְּבִיר

Question: In Y'hoshua 15:15, and again in Shof'tim 1:11, going to the city of דְּבִיר is referred to as "going to יוֹשְׁבֵי דְּבִיר" (something if not unique then nearly so (in Y'hoshua, anyway; I haven't learned much of Shof'tim recently)). Why?
Comment: Similar: http://judaism.stackexchange.com/q/48880
Answer: There are some other places where יושבי is used similarly. In Josh. 17:7 ישבי עין תפוח is used as a geographical marker, and in v. 11 there seems to be a distinction between the cities and their inhabitants: בית שאן... ויבלעם... ישבי דאר... וישבי עין דר... וישבי תענך... וישבי מגדו. But that just strengthens the question as to what this difference means.
It's possible that יושבי פלוני means "the people who resettled the city after it was abandoned (or destroyed) previously." We do find the kings of the "יושבי" cities listed among the 31 kings that Yehoshua defeated (Josh. 12:9ff): דביר, תפוח, דאר, תענך, מגדו. Whereas by contrast, בית שאן and יבלעם are indeed not listed there. So in other words, "going to יושבי דביר" would mean trying to dislodge the new inhabitants.
The problem I see with this idea is that it doesn't seem to fit the information given in Judges. In 1:27, where the list of Menashe's unconquered cities is repeated, תענך and יבלעם are switched around in position and in the presence or absence of ישבי. Also in vv. 31 and 33 several cities are mentioned with ישבי attached, but those are not among the earlier conquests.

יוֹשְׁבֵי דְּבִיר


In phase, out of phase pickups

Question: What is the purpose of having guitar pickups out of phase with each other?
Answer: It might help to understand what phase is and what people mean when they say "in phase" or "out of phase". Technically, phase is the amount of a wave that elapsed relative to some arbitrary point in time. If you consider a simple sinusoidal wave a phase of 0 degrees represents some arbitrary starting point of the wave, every time the wave passes through that same amplitude it's phase has increased by 180 degrees. Lets say we pick an amplitude of 0 as the starting point and we have a simple sinusoidal wave. At a phase of 180 degrees it will pass through zero again, but moving in the opposite direction, and at a phase of 360 degrees it will pass through zero again and be moving in the same direction as it was as 0 degrees.
If two waves are equal and "in phase" they are passing through the same amplitudes at the same time. When two waves are equal and in phase they sum to produce a wave that is twice the amplitude of either of the original waves. We call this constructive interference.
If two waves are equal and 180 degrees out of phase they are passing through opposite amplitudes at the same time. So when one wave is +1, the other would be -1. When two waves are equal and 180 degrees out phase they sum to produce a wave that always has zero amplitude. This is called destructive interference.
If we have an idealized setup, where two pickups are in the same spot on a guitar string, then their output should be exactly the same. In this setup, if they're wired in phase their signals will add and you'll get an output signal that is twice the volume of just one pickup or the other. If you wire up this idealized pickup scenario out of phase you'd hear nothing at all.
But in reality guitar pickups cannot be situated like this. They're always sampling a different part of the string (sometimes slightly as is the case of side-by-side pickups in a humbucker arrangement, sometimes considerably as is the case with a neck and bridge pickup). So the signals they're producing aren't exactly the same. That means combining them out-of-phase doesn't silence the output. Instead you get some interesting destructive interference happening that produces an output that's usually described as "quacky". It's missing some frequencies.
If you combine them in phase things don't get twice as loud, but they do get louder than either pickup on their own, as the same frequencies that were aligning to cancel out in the out-of-phase arrangement, align and add in a constructive interference pattern.
Comment: Note that out of phase pickups (like on a Strat), even if separated, will tend to cancel external noise like a humbucker.
Answer: Having pickups out of phase results in some more interesting sounds than what standard in-phase wirings can achieve. One of the most notable guitarists to use this sound is Jimmy Page of Led Zeppelin (among others) who had a myriad of wiring options available on his legendary Les Paul. Out of phase tones have a sort of hollow sound due to some frequency cancellation.
Speaking of that, from a physics standpoint having two pickups out of phase results in some signals produced cancelling out other frequencies. The more out-of-phase the pickups are, the more frequencies get cancelled, which makes the tone more unique and hollow. Also note that two (identical) signals that are 180 degrees out of phase with one another completely cancel each other out--but thankfully guitar pickups are at different positions on the body and relative to the strings--so that would almost never happen.
Note that the out-of-phase tone is not to be confused with the more hollow tones observed from a standard wired Fender Stratocaster at positions two and four. Some experts say these tones come from the characteristics of the single coil pickup along with the distances and position of those pickups relative to one another. The pickups are actually wired to be in-phase, but most guitarist mistakenly say they are out of phase.
Answer: A guitar whose pickups are in phase will typically sound different than a guitar whose pickups are out of phase.
This is because when electrical signals are combined, they can either reinforce each other, or cancel each other out.
Some guitars have a switch that reverses the phase of one of the pickups to create an in or out of phase condition.
I believe on the Strat, the middle pickup is wired up out of phase to provide hum cancellation.
Comment: The middle pickup is not out of phase in some cases, it's simply reverse wound. Think of a humbucker, which is two single coils wired in series with one another--one of them is wired in reverse (our opposite polarity). If a humbucker were out of phase with itself then it would sound very strange :D. Humbuckers are wired this way to "buck" the unique hum you hear on single coils.
Comment: On one of my home made guitars I wired in phase switches for each of the 4 pickups in a dual humbucker configuration. Ended up not using some sounds as they just didn't work, but switching phase on two pickups really close to each other gives a very interesting set of sounds.
Answer: Guitar pickups, in addition to amplifying the sound from the strings can also pick up other electrical currents, most especially 60Hz AC, that end up coming out of the amplifier as a humming sound.  But, since these AC signals are primarily picked up by the coil windings, if you have a set of two windings that are reversed from each other, the AC signals end up being 180 degrees out of phase with each other and are thereby canceled out.  Since the strings themselves are amplified using both the coil windings and the magnets, if the magnets are then placed opposite of each other (i.e. one pickup has north facing up while the other has south), the string signal ends up being doubled.
So, what you end up with is a stronger string single with less hum than you would otherwise have.
A better description of this can be found on the Wikipedia page for pickups: Pickup (music technology).

In phase, out of phase pickups


GParted is Frozen

Question: I've been trying to allocate more space for Windows... And to do that, I have to resize my Linux partition partition.
So I booted up from my flash drive and started up gParted. Everything was working great until gParted started to resize my Linux partition. It's been stuck at 6.33GB of 86.5GB copied for about half an hour now. The entire OS has stopped responding and the flash drive is flashing like it does when it's active.
I have Linux Mint 11 on my flash drive.
I'm not too particularly worried about losing my data. I have it all backed up, but it would be nice if this could be recovered. Any suggestions?
Answer: If it's hung, then it's hung... time to cut power and restore from backup.

GParted is Frozen


Kamakura, Japan: Feasibility of day trip from Tokyo?

Question: I will be in Tokyo for a conference and was hoping to check out Kamakura for a visit.
Is it practical to travel to Kamakura for a day trip, or should I look into overnight accommodations?
Comment: Welcome to the site.  Pleas read the [faq] as your question is in danger of being closed for soliciting opinion without detail.  Maybe you could indicate what it is you're hoping to check out in Kamakura, so people can help indicate how long that might take.
Answer: I'll try to answer on the assumption that you're asking mostly about the relative practicality of a day trip, rather than asking for a sort of value judgment on the merits of an overnight.
You can see a number of popular tourist destinations on a day trip to Kamakura from Tokyo. Additionally, it's a somewhat sleepy city that, in comparison to much of Tokyo or Yokohama, as temples and shrines close to the public around sunset and retail mostly sort of shuts down around 5:30-6pm or so, and unless you're staying for an unusually late dinner and drinks sort of thing, it's perfectly easy to get back to nearly anywhere in Tokyo as long as you leave by 10pm or so.
Train frequency decreases later in the evening, and that's the main risk you have to getting back to your hotel. If you plan ahead or use the mobile version of Jorudan's Norikae web site, that shouldn't be a big problem.
The primary benefit of an overnight is that it simply isn't practical to see more than two or three of the major shrines/temples in a single day. Some of the best known ones, like the Daibutsu at Kōtoku-in, can be a pretty substantial walk from other major destinations, like Hachimangu Shrine, so if you have a long list of places you'd like to see and you're not motivated to navigate local buses or take taxis to reduce your travel time, or if it happens to be a busy tourist season or pilgrimage season with lots of lines, you might lose a lot of time to travel and waiting. If you have lots of places you want to see, and you want to navigate the little shops selling lacquerware and leather goods and so on that Kamakura is fairly well known for, allow time for lunch and snacks, and stop impromptu at whatever sights you stumble on without advance planning, it can be nice to have the advantages of an early morning after an overnight stay so that you don't have to push yourself too hard.
Answer: It only takes an hour to get there from Toyko Station, so I would probably only do a day trip. It does of course depend on how you like to travel and how much you want to see there, although at only an hour it's faster then most work commutes in Los Angeles.
Answer: You can keep the travel time down to 45-50 min. one way if you plan in advance. And it depends where you are staying in Tokyo.
I think the most convenient is if you are staying around the southern part of Tokyo. For example, if you are near to or can easily get to Shinagawa station, you can take the JR Yokosuka line to Kamakura (51 min. / Y690). You can find current train schedules on Hyperdia and other websites.
Because its so close to Tokyo, even if you return to Tokyo and go back the next day, it should be easier than making a separate reservation around Kamakura.
But as JasonTrue mentioned, you should plan where you want to go in advance. Some places are hard to find, and keep in mind that you will be walking a lot. A couple of websites to check out:
http://www.japan-guide.com/e/e2166.html
http://www.kamakuratoday.com/e/sightseeing.html
Though its a way outside Kamakura itself, the Daibutsu (Great Buddha) is a must see and on most every tourists agenda.
Answer: I would also do a day-trip. I've done that a few times and it's a fantastic day out. To make the most out of your day trip, you might want to consider rentinga bicycle at the station in Kamakura. This gives you the chance to move around quicker and see much more than you would using the bus or just walking.
Here's a suggested itinerary:
http://japantourist.jp/view/kamakura-by-bicyle
As for the train timetable, I find this one very useful:
http://www.hyperdia.com
Comment: Please disclose that you're associated with the site when posting answers, otherwise this will be considered and dealt with as spam.


What should I look for in a torque wrench?

Question: It has come to the point where I need a torque wrench for installing things on my bicycle. What should I look for when purchasing one?
Comment: possible duplicate of http://bicycles.stackexchange.com/questions/3450/how-to-objectively-evaluate-torque-wrenches
Answer: You want to make sure that it will serve the range of torques that you will realistically be using.  Most bicycle tasks will require quite a low torque (e.g. 8 Nm) but occasionally (crank bolts, pinch bolts) you'll need much higher torques (e.g. 50NM).
I have 2 torque wrenches, a 'sensitive' one which ranges from about 5NM to 20NM (in fine graduations) and a medium duty one that ranges from about 20NM to 100NM (in broader and less accurate graduations).
It's handy to have measurements in NM and lbFt, but I'm sure every torque wrench on the market will display both values.
Most torque wrenches accept square drive sockets but the really swish ones also have adapters that let you use open wrench heads. This is great for places, such as the pedal axle, where you couldn't use a socket (Beta do such ones).
If you already own a lot of square drive sockets, then you may want to get a torque wrench that accepts the same size.
Tip: ALWAYS unwind your wrench after using it. Storing it 'torqued up' will affect it's calibration.
Answer: Some jobs require working with left-hand threads, for example, fitting cups to a BSA-threaded bottom bracket or fitting pedals.  This is more likely a requirement for your medium duty, higher torque wrench.
Some torque wrenches advertise 'reversible' ratchet heads but this is not the same thing.  Unless it specifically says so, the wrench is unlikely to work on left-hand threads.
Comment: Your simple beam-type torque wrench works equally well left or right.


Call of Duty 4 Modern Warfare modding?

Question: I'm seeing a lot of Modern Warfare (the first one) mods out there, and I've come across at least one post that says that Activision released official modding tools for CoD4, but I can't seem to find them, or any reference to them on official websites.
Have official tools been released? Or are all these modding tools the result of reverse engineering and clever hacking, ala Diablo 2? I'm interested in getting into modding myself, I used to do Duke3D maps with the Build engine back in the day, even had a book on it, and it'd be great if I could do
Answer: They have been released, find them here.
Also, you may want to up your Google skills.
And, here is a tutorial to get you started.

Call of Duty 4 Modern Warfare modding?


How does a server obtain the IP Address of a user?

Question: How does a server obtain the IP Address of a user? Is it possible to fool the server by spoofing the IP Address?
Answer: When you send a request to the server, the server need to know where to answer, it's with your ip address. This is directly based on the TCP/IP protocol and in a lower level than web servers.
For the reason why Firebug doesn't show your IP address, it's like when you receive mail (paper), you have your address written in front, and the sender in the back. Firebugs shows you the content of the letter, not the sender and the receiver address (IP in IT).
Answer: Source IP address is being sent on different level. If you want to see it, you need to use different tool (e.g. Wireshark, Packetyzer or Microsoft Network Monitor). Firebug displays only HTTP requests not the IP connection details.
To spoof the source IP address, you can use some Packet generator - keep in mind that when you spoof the source IP address, the server will respond to that source address. Watch this video to find out more about the IP Spoofing.
Comment: @BlueRaja-DannyPflughoeft Is your comment because the IP connection details are part of the network layer, not the transport layer (TCP)?
Comment: "IP address" would be the "IP connection details," not TCP
Comment: @BlueRaja-DannyPflughoeft Correct, I changed it in the answer. Thanks.
Answer: As explained before, When you request a page to a web server, your address is basically needed for the reply. This is a basic networking principle, to read a bit more about it, you could look up these videos on youtube CCNA IP ADDRESSES.
You could spoof your ip address by using simple C code, such as shown here UDP Flooder, in this case the code use random IP addresses or defined IP addresses to flood a phone, and the phone only replies via PING to a random or crafted IP address.
(notice, that this tools as been made for testing purposes only, and can only be used on your own equipement)
And finally if you want to play with network packets, there is this good tutorial about scapy
Here which allow you to forge packets. (basically the tutorial shows you how to make a Man In the Middle with Scapy)
Answer: A HTTP header from your computer is in the highest layer of the OSI Model (Application Layer, Layer 7), as it moves through each layer in your device it applies a new header. Your IP Address will not be added until the Network Layer (Layer 3). Firebug will only look at the HTTP headers you are sending, not inspect the traffic lower down in the network stack.
It is possible to change your IP address using a proxy or VPN for example. However if you spoof an IP address the server will send the response to that spoofed IP Address, so this it is mainly used when you wish to conceal your identity and do not worry about about the return packets. Read up on IP Address Spoofing  for more information.
Answer: If you wish to "hide" your IP address when talking to a server, you could send your traffic through a proxy. Then the server will see the proxy's IP address instead of "yours".
If you're looking for an anonymizing service, you could search for VPN tunnel providers or have a look at Tor, the onion router project.
Answer: THe Client IP address can be captured in the X-Forwarded-For  field in the HTTP headers, if the box has enabled for this. In web farms it's usually configured on a server load balancer. Configuration is necessary if there is a NAT device in the path.


How can I fix or stop moisture damage caused by the kitchen sink?

Question: So we recently moved into a new place and it seems like the kitchen faucet use to leak at some stage and that the previous owners did fix this, but now behind the kitchen sink by the tiles, there is some kind of a moisture problem. It does have a white seal or something similar on, but this is also starting to come loose. Is there anyway to repair this damage or patch it up?
Comment: your question is pretty vague. Can you post a picture or more accurately describe the "white seal" and what kind of moisture damage.
Comment: Are you referring to the caulking?
Answer: sometimes when water or moisture gets trapped under or behind something it can linger for a long time and may not dry out until it is exposed to open air, yes, just about anything can be repaired that is water damaged
Answer: If there is still an ongoing moisture problem under your sink, then your sink is still leaking. If its a slight moisture problem (rather than a dramatic noticable leak when you turn on the faucet) then it's probably actually the drainage pipe which is leaking.  Fill your sink with water, then check your drainage pipe.  If its dry, then drain the sink completely and check the drainage pipe again.  If it's is wet after this experiment then its definitely a drainage issue.  If so, I recommend tightly wrapping black electrical tape around all the joint-connectors of the drainage pipe and calling a plumber when you have a few hundred bucks available to get it fixed.


homemade wine problem

Question: My question is in my primary fermenter. If the airlock is not bubbling does that mean its not fermenting. I have two on the go one is bubbling and the other one is. What should I do?
Answer: The only way to be sure if it is fermenting is to check the gravity.  If the airlock is not bubbling it could just mean the seal on the bucket lid (or stopper) is not sealed air-tight.  It may also need more time before it kicks up.  The only time I fermented wine, it was a much less active-looking fermentation than beer.  I'd say wait a day or two, then take a gravity reading.  If it hasn't dropped, pitch more yeast.
Answer: I agree about the bucket seal and a gravity reading, but if you have one active fermentation and one inactive, I would decant the active wine into a secondary, and siphon the other onto the yeast cake in the active primary.  The fermentation would pick up faster than repitching since the yeast is fully active and dispersed in an identical solution.  Wine yeasts are strong fermenters so I wouldn't be concerned about thinning the pitching rate.

homemade wine problem


What could be causing this leak near my chimney?

Question: I had a new roof put on in 2010 and had no problems... recently I've noticed that I'm getting water in my house. Its coming down along side where my chimney is and making large bubbles in my walls. We had the roofer come out thinking something was wrong with the flashing. He informed us that everything looked good up on the roof and maybe the water was due to condensation, and the bricks soaking up the rains and therefore coming in. He told us to just scrap the wall but today we had rain and my wall looks worse. I hate to scrap and repair my wall and it continue. Can someone please tell me what it sounds like it could be. I have a cap on the chimney. The roofer did recommend "sealing the brick". I'm lost as to where to go next with this issues.
Comment: Can you get into the attic space and look for signs of water penetration?
Answer: Without pictures of the roof, and the problem, this is very hard to diagnose accurately but here are a few common things it could be.
1) The Roof could be leaking from somewhere near-by.  A rusty nail head could pop through a shingle etc..  You mention the roof is fairly new, this is unlikely.
2) The leak could be from in side the chimney if it isnt capped.. have you had the inside inspected / do you burn the fireplace?
3) There could be structural damage to the fireplace. Ridge cap could be installed in correctly, there could be a problem with the fascia boards.
I live in the pacific northwest, and have never once heard of someone having to seal their brick fireplace. While its possible, I belive this to also be a waste of your time.  Unless this is a unicorn problem, I belive this problem could be solved with finding the leak, but I would need pictures, or to see it in person to make a better judgement.


How to delete images already imported into iPhoto?

Question: I have a large number of random folders of photos on my hard drive, some of which have been imported into iPhoto. How do I figure out which photos have been imported into iPhoto, so I can delete the non-iPhoto copies?
Answer: If you batch drag them, as jmlumpkin suggested, a number of them will be spotted with the 'do you want to import again', and you can apply no to all, then delete the bunch. If hwoever, it accepts them, there are a few bits of duplicate finder software - none of them free (at least not that I've found), but at around $8 - http://www.brattoo.com/propaganda/.
I'd love to find something free that did the same!
Other helpful things: It may take some time, but letting faces do its thing, you will be able to group up and spot some duplicates.
Answer: I would drag each photo to iPhoto individually. It should then tell you 'these already exist in your library, do you want to import again, etc'. I would then visually check to make sure that they are in there, and then delete the folder.
If it doesn't give you that message, then you would go ahead and import them, and then can remove the original folder.
Answer: You can delete all duplicate photos under "Last import" section after import


What type of sub-floor is suitable for laminate flooring?

Question: I'm planning to put laminate type of floating flooring on a floor.  The floor has a sub-flooring of 3/4 inch planks and a sheathing of 1/4 inch plywood.  I would like to remove the plywood because its thickness will cause a bigger lip at the junction of the room and the hall.  Is it ok to install an underlayment of thin foam and the floating flooring directly on the sub-floor planks (assuming they're pretty level)?
Answer: The 1/4" plywood is likely luan. It's used to level the floor, often for a vinyl floor. For a hardwood floor, the main reason to have luan is shore up the floor and reduce any pitting or other slope issues. Whether you can remove the luan depends on the quality of your subfloor. If it has any imperfections, I would keep (or replace) the luan.
Answer: We got lucky and were (mostly) able to put laminate over 3/4" OSB subfloor. Some places, though, it required additional leveling. As BMitch said, you probably want to keep the luan.
Once you remove whatever floor covering you have now, go over the remaining surface carefully with a long straight edge such as a beam level. The flatter you can get the floor, the easier your laminate install will be.


What effect does the alkalinity of wort have on the fermentation cycle in beer brewing?

Question: What effect does the alkalinity of wort have on the fermentation cycle in beer brewing?
Answer: Alkalinity really doesn't apply in the discussion of wort since the pH of wort should be below 7 thus making it an acidic solution.
Most of the discussion of pH during fermentation revolves around the yeast ability to reduce the pH and the available buffering materials present such as FAN(free available nitorgen).  During the fermentation process organic acids are produced from yeast byproducts causing a drop in the overall pH level.  The drop is significant in ale yeast during the first 12 hours(.4-.6) and much less so with lager yeast(.5 in 48 hours).  The presence of large quantities of FAN not only spurs yeast growth and the production of organic acids it also buffers the acids moderating the drop in pH level.
Basically the lowering of the pH can reduce the production of dimethyl sulfide and is also used as a measure of fermentation health and fermentation completion.