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An 1817 Boulton & Watt beam blowing engine, used in Netherton at the ironworks of M W Grazebrook. Re-erected on the A38(M) in Birmingham, UK A mill engine from Stott Park Bobbin Mill, Cumbria, England A steam locomotive from East Germany. This class of engine was built in 1942–1950 and operated until 1988. From Wikipedia, the free encyclopedia A steam engine is a heat engine that performs mechanical work using steam as its working fluid. Steam engines are external combustion engines,[1] where the working fluid is separate from the combustion products. Non-combustion heat sources such as solar power, nuclear power or geothermal energy may be used. The ideal thermodynamic cycle used to analyze this process is called the Rankine cycle. In the cycle, water is heated and transforms into steam within a boiler operating at a high pressure. When expanded through pistons or turbines, mechanical work is done. The reduced- pressure steam is then condensed and pumped back into the boiler. In general usage, the term steam engine can refer to either the integrated steam plants (including boilers etc.) such as railway steam locomotives and portable engines, or may refer to the piston or turbine machinery alone, as in the beam engine and stationary steam engine. Specialized devices such as steam hammers and steam pile drivers are dependent on the steam pressure supplied from a separate boiler. The use of boiling water to produce mechanical motion goes back over 2000 years, but early devices were not highly practical. The Spanish inventor Jerónimo de Ayanz y Beaumont obtained the first patent for a steam engine in 1606.[2] In 1698 Thomas Savery patented a steam pump that used steam in direct contact with the water being pumped. Savery's steam pump used condensing steam to create a vacuum and draw water into a chamber, and then applied pressurized steam to further pump the water. Thomas Newcomen's atmospheric engine was the first commercial true steam engine using a piston, and was used in 1712 for pumping in a mine. In 1781 James Watt patented a steam engine that produced continuous rotary motion.[3] Watt's ten-horsepower engines enabled a wide range of manufacturing machinery to be powered. The engines could be sited anywhere that water and coal or wood fuel could be obtained. By 1883, engines that could provide 10,000 hp had become feasible.[4] The stationary steam engine was a key component of the Industrial Revolution, allowing factories to locate where water power was unavailable. The atmospheric engines of Newcomen and Watt were large compared to the amount of power they produced, but high-pressure steam engines were light enough to be applied to vehicles such as traction engines and the railway locomotives. Reciprocating piston type steam engines remained the dominant source of power until the early 20th century, when advances in the design of electric motors and internal combustion engines gradually resulted in the replacement of reciprocating (piston) steam engines in commercial usage, and the ascendancy of steam Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 1 of 21 1/4/2017 9:21 PM turbines in power generation.[5] Considering that the great majority of worldwide electric generation is produced by turbine type steam engines, the "steam age" is continuing with energy levels far beyond those of the turn of the 19th century. 1 History 1.1 Early designs and modifications 1.2 Early experiments 1.3 Pumping engines 1.4 Piston steam engines 1.5 High-pressure engines 1.6 Horizontal stationary engine 1.7 Road vehicles 1.8 Marine engines 1.9 Steam locomotives 1.10 Steam turbines 1.11 Present development 2 Components and accessories of steam engines 2.1 Heat source 2.2 Boilers 2.3 Motor units 2.4 Cold sink 2.5 Water pump 2.6 Monitoring and control 2.7 Governor 3 Engine configuration 3.1 Simple engine 3.2 Compound engines 3.3 Multiple-expansion engines 4 Types of motor units 4.1 Reciprocating piston 4.2 Uniflow (or unaflow) engine 4.3 Turbine engines 4.4 Oscillating cylinder steam engines 4.5 Rotary steam engines 4.6 Rocket type 5 Safety 6 Steam cycle 7 Efficiency 8 See also 9 References 10 Bibliography 11 Further reading 12 External links Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 2 of 21 1/4/2017 9:21 PM Early designs and modifications The aeolipile (also known as a Hero engine) described by Hero of Alexandria in the 1st century AD is considered to be the first recorded steam engine. Torque was produced by steam jets exiting the turbine. Thomas Savery, in 1698, patented the first practical, atmospheric pressure, steam engine of 1 horsepower (750 W). It had no piston or moving parts, only taps. It was a fire engine, a kind of thermic syphon, in which steam was admitted to an empty container and then condensed. The vacuum thus created was used to suck water from the sump at the bottom of the mine. The "fire engine" was not very effective and could not work beyond a limited depth of around 30 feet (9.1 m). Thomas Newcomen, in 1712, developed the first commercially successful piston steam engine of 5 horsepower (3,700 W). Its principle was to condense steam in a cylinder, thus causing atmospheric pressure to drive a piston and produce mechanical work. James Watt, in 1781, patented a steam engine that produced continued rotary motion with a power of about 10 horsepower (7,500 W). It was the first type of steam engine to make use of steam at a pressure just above atmospheric to drive the piston helped by a partial vacuum. It was an improvement of Newcomen's engine. Richard Trevithick, It was only after the invention of the lightweight, high pressure, steam engine by Richard Trevithick, in 1797-1799 that steam engines became small enough to be used in smaller businesses and for use in steam locomotives. Since the early 18th century, steam power has been applied to a variety of practical uses. At first it powered reciprocating pumps, but from the 1780s rotative engines (those converting reciprocating motion into rotary motion) began to appear, driving factory machinery such as spinning mules and power looms. At the turn of the 19th century, steam-powered transport on both sea and land began to make its appearance, becoming more dominant as the century progressed. Steam engines can be said to have been the moving force behind the Industrial Revolution and saw widespread commercial use driving machinery in factories, mills and mines; powering pumping stations; and propelling transport appliances such as railway locomotives, ships, steamboats and road vehicles. Their use in agriculture led to an increase in the land available for cultivation. There have at one time or another been steam-powered farm tractors, motorcycles (without much success) and even automobiles as the Stanley Steamer.[6] The weight of boilers and condensers generally makes the power-to-weight ratio of a steam plant lower than for internal combustion engines.[7] For mobile applications steam has been largely superseded by internal combustion engines or electric motors. However, most electric power is generated using steam turbine plant, so that indirectly the world's industry is still dependent on steam power. Recent concerns about fuel sources and pollution have incited a renewed interest in steam both as a component of cogeneration processes and as a prime mover. This is becoming known as the Advanced Steam movement. Early experiments The history of the steam engine stretches back as far as the first century AD; the first recorded rudimentary steam engine being the aeolipile described by Greek mathematician Hero of Alexandria.[8] In the following centuries, the few steam-powered "engines" known were, like the aeolipile,[9] essentially experimental devices used by inventors to demonstrate the properties of steam. A rudimentary steam turbine device was described by Taqi al-Din[10] in 1551 and by Giovanni Branca[11] in 1629.[12] Jerónimo de Ayanz y Beaumont received Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 3 of 21 1/4/2017 9:21 PM Jacob Leupold Steam engine 1720 patents in 1606 for fifty steam powered inventions, including a water pump for draining inundated mines.[13] Denis Papin, a Huguenot refugee, did some useful work on the steam digester in 1679, and first used a piston to raise weights in 1690.[14] Pumping engines The first commercial steam-powered device was a water pump, developed in 1698 by Thomas Savery.[15] It used condensing steam to create a vacuum which was used to raise water from below, then it used steam pressure to raise it higher. Small engines were effective though larger models were problematic. They proved only to have a limited lift height and were prone to boiler explosions. It received some use in mines, pumping stations and for supplying water wheels used to power textile machinery.[16] An attractive feature of the Savery engine was its low cost. Bento de Moura Portugal introduced an ingenious improvement of Savery's construction "to render it capable of working itself", as described by John Smeaton in the Philosophical Transactions published in 1751.[17] It continued to be manufactured until the late 18th century.[18] One engine was still known to be operating in 1820.[19] Piston steam engines The first commercially successful true engine, in that it could generate power and transmit it to a machine, was the atmospheric engine, invented by Thomas Newcomen around 1712.[20][21] It was an improvement over Savery's steam pump, using a piston as proposed by Papin. Newcomen's engine was relatively inefficient, and in most cases was used for pumping water. It worked by creating a partial vacuum by condensing steam under a piston within a cylinder. It was employed for draining mine workings at depths hitherto impossible, and also for providing a reusable water supply for driving waterwheels at factories sited away from a suitable "head". Water that had passed over the wheel was pumped back up into a storage reservoir above the wheel.[22] In 1720 Jacob Leupold described a two-cylinder high-pressure steam engine.[23] The invention was published in his major work "Theatri Machinarum Hydraulicarum".[24] The engine used two heavy pistons to provide motion to a water pump. Each piston was raised by the steam pressure and returned to its original position by gravity. The two pistons shared a common four way rotary valve connected directly to a steam boiler. The next major step occurred when James Watt developed (1763–1775) an improved version of Newcomen's engine, with a separate condenser. Boulton and Watt's early engines used half as much coal as John Smeaton's improved version of Newcomen's.[25] Newcomen's and Watt's early engines were "atmospheric". They were powered by air pressure pushing a piston into the partial vacuum generated by condensing steam, instead of the pressure of expanding steam. The engine cylinders had to be large because the only usable force acting on them was due to atmospheric pressure.[22][26] Watt proceeded to develop his engine further, modifying it to provide a rotary motion suitable for driving factory machinery. This enabled factories to be sited away from rivers, and further accelerated the pace of the Industrial Revolution.[26][27][28] High-pressure engines Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 4 of 21 1/4/2017 9:21 PM Early Watt pumping engine Watt's patent prevented others from making high pressure and compound engines. Shortly after Watt's patent expired in 1800, Richard Trevithick and, separately, Oliver Evans in 1801[28][29] introduced engines using high-pressure steam; Trevithick obtained his high-pressure engine patent in 1802,[30] and Evans had made several working models before then.[31] These were much more powerful for a given cylinder size than previous engines and could be made small enough for transport applications. Thereafter, technological developments and improvements in manufacturing techniques (partly brought about by the adoption of the steam engine as a power source) resulted in the design of more efficient engines that could be smaller, faster, or more powerful, depending on the intended application.[22] The Cornish engine was developed by Trevithick and others in the 1810s.[32] It was a compound cycle engine that used high-pressure steam expansively, then condensed the low-pressure steam, making it relatively efficient. The Cornish engine had irregular motion and torque though the cycle, limiting it mainly to pumping. Cornish engines were used in mines and for water supply until the late 19th century.[33] Horizontal stationary engine Early builders of stationary steam engines considered that horizontal cylinders would be subject to excessive wear. Their engines were therefore arranged with the piston axis vertical. In time the horizontal arrangement became more popular, allowing compact, but powerful engines to be fitted in smaller spaces. The acme of the horizontal engine was the Corliss steam engine, patented in 1849, which was a four-valve counter flow engine with separate steam admission and exhaust valves and automatic variable steam cutoff. When Corliss was given the Rumford Medal, the committee said that "no one invention since Watt's time has so enhanced the efficiency of the steam engine".[34] In addition to using 30% less steam, it provided more uniform speed due to variable steam cut off, making it well suited to manufacturing, especially cotton spinning. [22][28] Road vehicles The first experimental road going steam powered vehicles were built in the late 18th century, but it was not until after Richard Trevithick had developed the use of high-pressure steam, around 1800, that mobile steam engines became a practical proposition. The first half of the 19th century saw great progress in steam vehicle design, and by the 1850s it was becoming viable to produce them on a commercial basis. This progress was dampened by legislation which limited or prohibited the use of steam powered vehicles on roads. Improvements in vehicle technology continued from the 1860s to the 1920s. Steam road vehicles were used for many applications. In the 20th century, the rapid development of internal combustion engine technology led to the demise of the steam engine as a source of propulsion of vehicles on a commercial basis, with relatively few remaining in use beyond the Second World War. Many of these vehicles were acquired by enthusiasts for preservation, and numerous examples are still in existence. In the 1960s the air pollution problems in California gave rise to a brief period of interest in developing and studying steam powered vehicles as a possible means of reducing the pollution. Apart from interest by steam enthusiasts, the occasional replica vehicle, and experimental technology no steam vehicles are in production at present. Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 5 of 21 1/4/2017 9:21 PM A triple-expansion marine steam engine on the 1907 oceangoing tug Hercules Marine engines Near the end of the 19th century compound engines came into widespread use. Compound engines exhausted steam in to successively larger cylinders to accommodate the higher volumes at reduced pressures, giving improved efficiency. These stages were called expansions, with double- and triple-expansion engines being common, especially in shipping where efficiency was important to reduce the weight of coal carried.[22] Steam engines remained the dominant source of power until the early 20th century, when advances in the design of electric motors and internal combustion engines gradually resulted in the replacement of reciprocating (piston) steam engines, with shipping in the 20th-century relying upon the steam turbine.[5] Steam locomotives As the development of steam engines progressed through the 18th century, various attempts were made to apply them to road and railway use.[35] In 1784, William Murdoch, a Scottish inventor, built a prototype steam road locomotive.[36] An early working model of a steam rail locomotive was designed and constructed by steamboat pioneer John Fitch in the United States probably during the 1780s or 1790s.[37] His steam locomotive used interior bladed wheels guided by rails or tracks. The first full-scale working railway steam locomotive was built by Richard Trevithick in the United Kingdom and, on 21 February 1804, the world's first railway journey took place as Trevithick's unnamed steam locomotive hauled a train along the tramway from the Pen-y-darren ironworks, near Merthyr Tydfil to Abercynon in south Wales.[35][38][39] The design incorporated a number of important innovations that included using high-pressure steam which reduced the weight of the engine and increased its efficiency. Trevithick visited the Newcastle area later in 1804 and the colliery railways in north-east England became the leading centre for experimentation and development of steam locomotives.[40] Trevithick continued his own experiments using a trio of locomotives, concluding with the Catch Me Who Can in 1808. Only four years later, the successful twin-cylinder locomotive Salamanca by Matthew Murray was used by the edge railed rack and pinion Middleton Railway.[41] In 1825 George Stephenson built the Locomotion for the Stockton and Darlington Railway. This was the first public steam railway in the world and then in 1829, he built The Rocket which was entered in and won the Rainhill Trials.[42] The Liverpool and Manchester Railway opened in 1830 making exclusive use of steam power for both passenger and freight trains. Steam locomotives continued to be manufactured until the late twentieth century in places such as China and the former East Germany (where the DR Class 52.80 was produced).[43] Steam turbines The final major evolution of the steam engine design was the use of steam turbines starting in the late part of the 19th century. Steam turbines are generally more efficient than reciprocating piston type steam engines (for outputs above several hundred horsepower), have fewer moving parts, and provide rotary power directly instead of through a connecting rod system or similar means.[44] Steam turbines virtually replaced reciprocating engines in electricity generating stations early in the 20th century, where their efficiency, higher Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 6 of 21 1/4/2017 9:21 PM speed appropriate to generator service, and smooth rotation were advantages. Today most electric power is provided by steam turbines. In the United States 90% of the electric power is produced in this way using a variety of heat sources.[5] Steam turbines were extensively applied for propulsion of large ships throughout most of the 20th century. Present development Although the reciprocating steam engine is no longer in widespread commercial use, various companies are exploring or exploiting the potential of the engine as an alternative to internal combustion engines. The company Energiprojekt AB in Sweden has made progress in using modern materials for harnessing the power of steam. The efficiency of Energiprojekt's steam engine reaches some 27-30% on high-pressure engines. It is a single-step, 5-cylinder engine (no compound) with superheated steam and consumes approx. 4 kg (8.8 lb) of steam per kWh.[45] There are two fundamental components of a steam plant: the boiler or steam generator, and the "motor unit", referred to itself as a "steam engine". Stationary steam engines in fixed buildings may have the boiler and engine in separate buildings some distance apart. For portable or mobile use, such as steam locomotives, the two are mounted together.[46][47] The widely used reciprocating engine typically consisted of a cast iron cylinder, piston, connecting rod and beam or a crank and flywheel, and miscellaneous linkages. Steam was alternately supplied and exhausted by one or more valves. Speed control was either automatic, using a governor, or by a manual valve. The cylinder casting contained steam supply and exhaust ports. Engines equipped with a condenser are a separate type than those that exhaust to the atmosphere. Other components are often present; pumps (such as an injector) to supply water to the boiler during operation, condensers to recirculate the water and recover the latent heat of vaporisation, and superheaters to raise the temperature of the steam above its saturated vapour point, and various mechanisms to increase the draft for fireboxes. When coal is used, a chain or screw stoking mechanism and its drive engine or motor may be included to move the fuel from a supply bin (bunker) to the firebox.[48] See: Mechanical stoker Heat source The heat required for boiling the water and supplying the steam can be derived from various sources, most commonly from burning combustible materials with an appropriate supply of air in a closed space (called variously combustion chamber, firebox). In some cases the heat source is a nuclear reactor, geothermal energy, solar energy or waste heat from an internal combustion engine or industrial process. In the case of model or toy steam engines, the heat source can be an electric heating element. Boilers Boilers are pressure vessels that contain water to be boiled, and some kind of mechanism for transferring the heat to the water so as to boil it.[49] The two most common methods of transferring heat to the water are: Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 7 of 21 1/4/2017 9:21 PM An industrial boiler used for a stationary steam engine A power station's cooling tower produces clouds from the condensing water vapor due to evaporated cooling water. water-tube boiler – water is contained in or run through one or several tubes surrounded by hot gases 1. fire-tube boiler – the water partially fills a vessel below or inside which is a combustion chamber or furnace and fire tubes through which the hot gases flow 2. Fire tube boilers were the main type used for early high-pressure steam (typical steam locomotive practice), but they were to a large extent displaced by more economical water tube boilers in the late 19th century for marine propulsion and large stationary applications. Once turned to steam, many boilers raise the temperature of the steam further, turning 'wet steam' into 'superheated steam'. This use of superheating avoids the steam condensing within the engine, and allows significantly greater efficiency.[50] Motor units In a steam engine, a piston or steam turbine or any other similar device for doing mechanical work takes a supply of steam at high pressure and temperature and gives out a supply of steam at lower pressure and temperature, using as much of the difference in steam energy as possible to do mechanical work. These "motor units" are often called 'steam engines' in their own right. They will also operate on compressed air or other gas. Cold sink As with all heat engines, the majority of primary energy must be emitted as waste heat at relatively low temperature.[51] The simplest cold sink is to vent the steam to the environment. This is often used on steam locomotives, as the released steam is vented up the chimney so as to increase the draw on the fire, which greatly increases engine power, but reduces efficiency. Sometimes the waste heat is useful itself, and in those cases very high overall efficiency can be obtained. For example, combined heat and power (CHP) systems use the waste steam for district heating, exceeding 80% combined efficiency.[51] Where CHP is not used, steam turbines in stationary power plants use surface condensers as a cold sink. The condensers are cooled by water flow from oceans, rivers, lakes, and often by cooling towers which evaporate water to provide cooling energy removal. The resulting condensed hot water, is then pumped back up to pressure and sent back to the boiler. A dry type cooling tower is similar to an automobile radiator and is used in locations where water is costly. Waste heat can also be ejected by evaporative (wet) cooling towers use pass the rejected to external water cycle that evaporates some of flow to the air. Cooling towers often have visible plumes due to the evaporated water condensing into droplets carried up by the warm air. Evaporative cooling towers need less water flow than "once-through" cooling by river or lake water; a 700 megawatt coal-fired power plant may use about 3600 cubic metres of Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 8 of 21 1/4/2017 9:21 PM An injector uses a jet of steam to force water into the boiler. Injectors are inefficient but simple enough to be suitable for use on locomotives. Richard's indicator instrument of 1875. See: Indicator diagram (below) make-up water every hour for evaporative cooling, but would need about twenty times as much if cooled by river water.[52][53] Evaporative water cannot be used for subsequent purposes (other than rain somewhere), whereas river water can be re-used. In all cases, the steam plant water, which must be kept pure, is kept separate from the cooling water or air, and once the low-pressure steam condenses into water, it is returned to the boiler. Water pump The Rankine cycle and most practical steam engines have a water pump to recycle or top up the boiler water, so that they may be run continuously. Utility and industrial boilers commonly use multi-stage centrifugal pumps; however, other types are used. Another means of supplying lower-pressure boiler feed water is an injector, which uses a steam jet usually supplied from the boiler. Injectors became popular in the 1850s but are no longer widely used, except in applications such as steam locomotives.[54] It is the pressurization of the water that circulates through the steam boiler that allows the water to be raised to temperatures well above 100 °C boiling point of water at one atmospheric pressure, and by that means to increase the efficiency of the steam cycle. Monitoring and control For safety reasons, nearly all steam engines are equipped with mechanisms to monitor the boiler, such as a pressure gauge and a sight glass to monitor the water level. Many engines, stationary and mobile, are also fitted with a governor to regulate the speed of the engine without the need for human interference. The most useful instrument for analyzing the performance of steam engines is the steam engine indicator. Early versions were in use by 1851,[55] but the most successful indicator was developed for the high speed engine inventor and manufacturer Charles Porter by Charles Richard and exhibited at London Exhibition in 1862.[28] The steam engine indicator traces on paper the pressure in the cylinder throughout the cycle, which can be used to spot various problems and calculate developed horsepower.[56] It was routinely used by engineers, mechanics and insurance inspectors. The engine indicator can also be used on internal combustion engines. See image of indicator diagram below (in Types of motor units section). Governor The centrifugal governor was adopted by James Watt for use on a steam engine in 1788 after Watt's partner Boulton saw one on the equipment of a flour mill Boulton & Watt were building.[57] The governor could not actually hold a set speed, because it would assume a new constant speed in response to load changes. The governor was able to handle smaller variations such as those caused by fluctuating heat load to the boiler. Also, Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 9 of 21 1/4/2017 9:21 PM Centrifugal governor in the Boulton & Watt engine 1788 Lap Engine. there was a tendency for oscillation whenever there was a speed change. As a consequence, engines equipped only with this governor were not suitable for operations requiring constant speed, such as cotton spinning.[58] The governor was improved over time and coupled with variable steam cut off, good speed control in response to changes in load was attainable near the end of the 19th century. Simple engine In a simple engine, the charge of steam passes through only one cylinder.[59] It is then exhausted directly into the atmosphere or into a condenser. As steam expands in passing through a high-pressure engine, its temperature drops because no heat is being added to the system; this is known as adiabatic expansion and results in steam entering the cylinder at high temperature and leaving at lower temperature. This causes a cycle of heating and cooling of the cylinder with every stroke, which is a source of inefficiency.[60] As the stroke of a single cylinder engine is increased in an effort to extract more work from the steam with each stroke, a greater amount of cylinder wall is exposed and more heat is lost, resulting in decreased efficiency of a long-stroke engine. Compound engines A method to lessen the magnitude of energy loss to a very long cylinder was invented in 1804 by British engineer Arthur Woolf, who patented his Woolf high-pressure compound engine in 1805. In the compound engine, high-pressure steam from the boiler expands in a high-pressure (HP) cylinder and then enters one or more subsequent lower-pressure (LP) cylinders. The complete expansion of the steam now occurs across multiple cylinders and as less cylinder wall is exposed, per unit volume of steam in each cylinder, less heat is lost by the steam in each. This reduces the magnitude of cylinder heating and cooling, increasing the efficiency of the engine. By staging the expansion in multiple cylinders, variations of torque can be reduced.[22] To derive equal work from lower-pressure cylinder requires a larger cylinder volume as this steam occupies a greater volume. Therefore, the bore, and often the stroke, are increased in low-pressure cylinders, resulting in larger cylinders.[22] Double-expansion (usually known as compound) engines expanded the steam in two stages. The pairs may be duplicated or the work of the large low-pressure cylinder can be split with one high-pressure cylinder exhausting into one or the other, giving a three-cylinder layout where cylinder and piston diameter are about the same, making the reciprocating masses easier to balance.[22] Two-cylinder compounds can be arranged as: Cross compounds: The cylinders are side by side. Tandem compounds: The cylinders are end to end, driving a common connecting rod Angle compounds: The cylinders are arranged in a V (usually at a 90° angle) and drive a common crank. Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 10 of 21 1/4/2017 9:21 PM An animation of a simplified triple- expansion engine. High-pressure steam (red) enters from the boiler and passes through the engine, exhausting as low-pressure steam (blue), usually to a condenser. With two-cylinder compounds used in railway work, the pistons are connected to the cranks as with a two-cylinder simple at 90° out of phase with each other (quartered). When the double-expansion group is duplicated, producing a four-cylinder compound, the individual pistons within the group are usually balanced at 180°, the groups being set at 90° to each other. In one case (the first type of Vauclain compound), the pistons worked in the same phase driving a common crosshead and crank, again set at 90° as for a two-cylinder engine. With the three-cylinder compound arrangement, the LP cranks were either set at 90° with the HP one at 135° to the other two, or in some cases all three cranks were set at 120°. The adoption of compounding was common for industrial units, for road engines and almost universal for marine engines after 1880; it was not universally popular in railway locomotives where it was often perceived as complicated. This is partly due to the harsh railway operating environment and limited space afforded by the loading gauge (particularly in Britain, where compounding was never common and not employed after 1930). However, although never in the majority, it was popular in many other countries.[61] Multiple-expansion engines It is a logical extension of the compound engine (described above) to split the expansion into yet more stages to increase efficiency. The result is the multiple-expansion engine. Such engines use either three or four expansion stages and are known as triple- and quadruple- expansion engines respectively. These engines use a series of cylinders of progressively increasing diameter. These cylinders are designed to divide the work into equal shares for each expansion stage. As with the double-expansion engine, if space is at a premium, then two smaller cylinders may be used for the low-pressure stage. Multiple-expansion engines typically had the cylinders arranged inline, but various other formations were used. In the late 19th century, the Yarrow-Schlick- Tweedy balancing "system" was used on some marine triple-expansion engines. Y-S-T engines divided the low-pressure expansion stages between two cylinders, one at each end of the engine. This allowed the crankshaft to be better balanced, resulting in a smoother, faster- responding engine which ran with less vibration. This made the four-cylinder triple-expansion engine popular with large passenger liners (such as the Olympic class), but this was ultimately replaced by the virtually vibration-free turbine engine. The image to the right shows an animation of a triple-expansion engine. The steam travels through the engine from left to right. The valve chest for each of the cylinders is to the left of the corresponding cylinder. Land-based steam engines could exhaust much of their steam, as feed water was usually readily available. Prior to and during World War I, the expansion engine dominated marine applications, where high vessel speed was not essential. It was, however, superseded by the British invention steam turbine where speed was required, for instance in warships, such as the dreadnought battleships, and ocean liners. HMS Dreadnought of 1905 was the first major warship to replace the proven technology of the reciprocating engine with the then-novel steam turbine.[62] Reciprocating piston Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 11 of 21 1/4/2017 9:21 PM Double acting stationary engine. This was the common mill engine of the mid 19th century. Note the slide valve with concave, almost "D" shaped, underside. Schematic Indicator diagram showing the four events in a double piston stroke. See: Monitoring and control (above) In most reciprocating piston engines, the steam reverses its direction of flow at each stroke (counterflow), entering and exhausting from the cylinder by the same port. The complete engine cycle occupies one rotation of the crank and two piston strokes; the cycle also comprises four events – admission, expansion, exhaust, compression. These events are controlled by valves often working inside a steam chest adjacent to the cylinder; the valves distribute the steam by opening and closing steam ports communicating with the cylinder end(s) and are driven by valve gear, of which there are many types. The simplest valve gears give events of fixed length during the engine cycle and often make the engine rotate in only one direction. Most however have a reversing mechanism which additionally can provide means for saving steam as speed and momentum are gained by gradually "shortening the cutoff" or rather, shortening the admission event; this in turn proportionately lengthens the expansion period. However, as one and the same valve usually controls both steam flows, a short cutoff at admission adversely affects the exhaust and compression periods which should ideally always be kept fairly constant; if the exhaust event is too brief, the totality of the exhaust steam cannot evacuate the cylinder, choking it and giving excessive compression ("kick back"). In the 1840s and 50s, there were attempts to overcome this problem by means of various patent valve gears with a separate, variable cutoff expansion valve riding on the back of the main slide valve; the latter usually had fixed or limited cutoff. The combined setup gave a fair approximation of the ideal events, at the expense of increased friction and wear, and the mechanism tended to be complicated. The usual compromise solution has been to provide lap by lengthening rubbing surfaces of the valve in such a way as to overlap the port on the admission side, with the effect that the exhaust side remains open for a longer period after cut-off on the admission side has occurred. This expedient has since been generally considered satisfactory for most purposes and makes possible the use of the simpler Stephenson, Joy and Walschaerts motions. Corliss, and later, poppet valve gears had separate admission and exhaust valves driven by trip mechanisms or cams profiled so as to give ideal events; most of these gears never succeeded outside of the stationary marketplace due to various other issues including leakage and more delicate mechanisms.[61][63] Compression Before the exhaust phase is quite complete, the exhaust side of the valve closes, shutting a portion of the exhaust steam inside the cylinder. This determines the compression phase where a cushion of steam is formed against which the piston does work whilst its velocity is rapidly decreasing; it moreover obviates the pressure and temperature shock, which would otherwise be caused by the sudden admission of the high-pressure steam at the beginning of the following cycle. Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 12 of 21 1/4/2017 9:21 PM Schematic animation of a uniflow steam engine. The poppet valves are controlled by the rotating camshaft at the top. High-pressure steam enters, red, and exhausts, yellow. A rotor of a modern steam turbine, used in a power plant Lead The above effects are further enhanced by providing lead: as was later discovered with the internal combustion engine, it has been found advantageous since the late 1830s to advance the admission phase, giving the valve lead so that admission occurs a little before the end of the exhaust stroke in order to fill the clearance volume comprising the ports and the cylinder ends (not part of the piston-swept volume) before the steam begins to exert effort on the piston.[64] Uniflow (or unaflow) engine Uniflow engines attempt to remedy the difficulties arising from the usual counterflow cycle where, during each stroke, the port and the cylinder walls will be cooled by the passing exhaust steam, whilst the hotter incoming admission steam will waste some of its energy in restoring working temperature. The aim of the uniflow is to remedy this defect and improve efficiency by providing an additional port uncovered by the piston at the end of each stroke making the steam flow only in one direction. By this means, the simple-expansion uniflow engine gives efficiency equivalent to that of classic compound systems with the added advantage of superior part-load performance, and comparable efficiency to turbines for smaller engines below one thousand horsepower. However, the thermal expansion gradient uniflow engines produce along the cylinder wall gives practical difficulties.. The Quasiturbine is a uniflow rotary steam engine where steam intakes in hot areas, while exhausting in cold areas. Turbine engines A steam turbine consists of one or more rotors (rotating discs) mounted on a drive shaft, alternating with a series of stators (static discs) fixed to the turbine casing. The rotors have a propeller-like arrangement of blades at the outer edge. Steam acts upon these blades, producing rotary motion. The stator consists of a similar, but fixed, series of blades that serve to redirect the steam flow onto the next rotor stage. A steam turbine often exhausts into a surface condenser that provides a vacuum. The stages of a steam turbine are typically arranged to extract the maximum potential work from a specific velocity and pressure of steam, giving rise to a series of variably sized high- and low-pressure stages. Turbines are only efficient if they rotate at relatively high speed, therefore they are usually connected to reduction gearing to drive lower speed applications, such as a ship's propeller. In the vast majority of large electric generating stations, turbines are directly connected to generators with no reduction gearing. Typical speeds are 3600 revolutions per minute (RPM) in the USA with 60 Hertz power, and 3000 RPM in Europe and other countries with 50 Hertz electric power systems. In nuclear power applications the turbines typically run at half these speeds, 1800 RPM and 1500 RPM. A turbine rotor is also only capable of providing power when rotating in one direction. Therefore, a reversing stage or gearbox is usually required Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 13 of 21 1/4/2017 9:21 PM Turbinia – the first steam turbine- powered ship Operation of a simple oscillating cylinder steam engine where power is required in the opposite direction. Steam turbines provide direct rotational force and therefore do not require a linkage mechanism to convert reciprocating to rotary motion. Thus, they produce smoother rotational forces on the output shaft. This contributes to a lower maintenance requirement and less wear on the machinery they power than a comparable reciprocating engine. The main use for steam turbines is in electricity generation (in the 1990s about 90% of the world's electric production was by use of steam turbines)[5] however the recent widespread application of large gas turbine units and typical combined cycle power plants has resulted in reduction of this percentage to the 80% regime for steam turbines. In electricity production, the high speed of turbine rotation matches well with the speed of modern electric generators, which are typically direct connected to their driving turbines. In marine service, (pioneered on the Turbinia), steam turbines with reduction gearing (although the Turbinia has direct turbines to propellers with no reduction gearbox) dominated large ship propulsion throughout the late 20th century, being more efficient (and requiring far less maintenance) than reciprocating steam engines. In recent decades, reciprocating Diesel engines, and gas turbines, have almost entirely supplanted steam propulsion for marine applications. Virtually all nuclear power plants generate electricity by heating water to provide steam that drives a turbine connected to an electrical generator. Nuclear-powered ships and submarines either use a steam turbine directly for main propulsion, with generators providing auxiliary power, or else employ turbo-electric transmission, where the steam drives a turbo generator set with propulsion provided by electric motors. A limited number of steam turbine railroad locomotives were manufactured. Some non-condensing direct-drive locomotives did meet with some success for long haul freight operations in Sweden and for express passenger work in Britain, but were not repeated. Elsewhere, notably in the U.S.A., more advanced designs with electric transmission were built experimentally, but not reproduced. It was found that steam turbines were not ideally suited to the railroad environment and these locomotives failed to oust the classic reciprocating steam unit in the way that modern diesel and electric traction has done. Oscillating cylinder steam engines An oscillating cylinder steam engine is a variant of the simple expansion steam engine which does not require valves to direct steam into and out of the cylinder. Instead of valves, the entire cylinder rocks, or oscillates, such that one or more holes in the cylinder line up with holes in a fixed port face or in the pivot mounting (trunnion). These engines are mainly used in toys and models, because of their simplicity, but have also been used in full size working engines, mainly on ships where their compactness is valued. Rotary steam engines It is possible to use a mechanism based on a pistonless rotary engine such as the Wankel engine in place of the cylinders and valve gear of a conventional reciprocating steam engine. Many such engines have been designed, from the time of James Watt Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 14 of 21 1/4/2017 9:21 PM An aeolipile rotates due to the steam escaping from the arms. No practical use was made of this effect. to the present day, but relatively few were actually built and even fewer went into quantity production; see link at bottom of article for more details. The major problem is the difficulty of sealing the rotors to make them steam-tight in the face of wear and thermal expansion; the resulting leakage made them very inefficient. Lack of expansive working, or any means of control of the cutoff is also a serious problem with many such designs. By the 1840s, it was clear that the concept had inherent problems and rotary engines were treated with some derision in the technical press. However, the arrival of electricity on the scene, and the obvious advantages of driving a dynamo directly from a high-speed engine, led to something of a revival in interest in the 1880s and 1890s, and a few designs had some limited success.. The Quasiturbine is a new type of uniflow rotary steam engine. Of the few designs that were manufactured in quantity, those of the Hult Brothers Rotary Steam Engine Company of Stockholm, Sweden, and the spherical engine of Beauchamp Tower are notable. Tower's engines were used by the Great Eastern Railway to drive lighting dynamos on their locomotives, and by the Admiralty for driving dynamos on board the ships of the Royal Navy. They were eventually replaced in these niche applications by steam turbines. Rocket type The aeolipile represents the use of steam by the rocket-reaction principle, although not for direct propulsion. In more modern times there has been limited use of steam for rocketry – particularly for rocket cars. Steam rocketry works by filling a pressure vessel with hot water at high pressure and opening a valve leading to a suitable nozzle. The drop in pressure immediately boils some of the water and the steam leaves through a nozzle, creating a propulsive force.[65] Steam engines possess boilers and other components that are pressure vessels that contain a great deal of potential energy. Steam escapes and boiler explosions (typically BLEVEs) can and have in the past caused great loss of life. While variations in standards may exist in different countries, stringent legal, testing, training, care with manufacture, operation and certification is applied to ensure safety. Failure modes may include: over-pressurisation of the boiler insufficient water in the boiler causing overheating and vessel failure buildup of sediment and scale which cause local hot spots, especially in riverboats using dirty feed water pressure vessel failure of the boiler due to inadequate construction or maintenance. escape of steam from pipework/boiler causing scalding Steam engines frequently possess two independent mechanisms for ensuring that the pressure in the boiler does not go too high; one may be adjusted by the user, the second is typically designed as an ultimate fail-safe. Such safety valves traditionally used a simple lever to restrain a plug valve in the top of a boiler. One end of the lever carried a weight or spring that restrained the valve against steam pressure. Early valves could be adjusted by engine drivers, leading to many accidents when a driver fastened the valve down to allow greater steam Steam engine - Wikipedia https://en.wikipedia.org/wiki/Steam_engine 15 of 21 1/4/2017 9:21 PM
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Last week, the kids at College Humor pulled off what we'd have to consider a prank of epic proportions; one guy put a fake marriage proposal on the big screen at Yankee Stadium as his friend, the object of the prank, sat agape with his girlfriend, who, amazingly, said "yes" before he had a chance to alert her to the joke. When we first watched it, it seemed too over-the-top to be real. But we've spoken with Amir Blumenfeld, the architect of the prank, and we now can merely salute him. (We think.) Watch the video, and then our interview with Amir is after the jump.
What game did you do this at?
Mariners at Yankees last Wednesday. The game where A-Rod hit two home runs in the seventh inning. Streeter would have seen a great ending!
Explain how the pranks progressed to this point of insanity.
It's hard to say... I think the biggest jump actually occurred from the first prank, where Streeter makes me listen to a sex tape of his, to the second prank, where I set him up on a fake date. Since then it's just been about finding a way to top the last one. I try to make sure the next one is either more embarrassing, on a grander scale, or in this case... BOTH!
That slap was what made us think it might have been faked. Slapping seems like something that only happens on Dynasty. We've seen the other pranks, so we know how it has escalated. But we have to ask: It's all definitely real, right?
Yeah, they are real. The funny part about the slap is, I have the raw footage of it from the close angle and I can't imagine why people accuse it of being fake. It was more of an open palm hit to Streeters face, but she actually connects with his neck pretty hard and he has no idea it's coming. It made a great sound.
As for why she did it, right before she swung at him, Streeter said, "I don't wanna fucking marry you!" If you watch the video again you can clearly hear it. It was a moment of great passion, and I was thrilled to catch it from two angles.
How well do you know their relationship? Did you think she'd be handle it OK? How long had they been dating?
Streeter and Sharon have been dating since college, so they've been together for about... three years. They made it through Prank War 2 (Streeter basically attempting to go on a date with another girl), so I'm sure they'll make it through Prank War 6. It's Prank War 8 I'm worried about. Just kidding.
Here's the $64,000 question: Are they still together? Did the guy kick your ass?
Yeah, they're still together. Since the prank, Sharon has been hating Streeter less and less and hating me more and more. But that's understandable; the prank was almost as much on her as it was on Streeter. I kinda felt bad about that.
Would you recommend someone else do this? Can this be topped?
It's funny, every single prank we release people are like "Oh man! This cannot be topped! This is the ultimate! The only way you can top this is if you kill so and so, or plan a fake funeral!" But I have always found a way to top the last one, and Streeter has as well. What makes it exceedingly difficult is that the more we prank each other, the more cautious/paranoid we become. That's why Streeter pranked me in May (Prank War 5), and I had to wait this long to get him back. I also had to wait for the Mariners to come into town, so it worked out particularly well.
After a few months you let your guard down... and then, just like that... you're done.

subset: commoncrawl


text:
Long before there were telescopes, astronomers or written history, people gazed up at "wandering stars" that later observers would call planets. As we applied our myths of faraway realms to these heavenly bodies, we began to wonder about the possibility of life on other worlds, an idea that has enthralled us ever since.
In recent decades, astronomers armed with radio telescopes, orbital observatories and other powerful high-tech tools have begun to answer that question. In 1995, University of Geneva astronomers Michel Mayor and Didier Queloz announced the discovery of the first planet outside our solar system, a Jupiterlike giant orbiting around a "main sequence" star similar to our sun, 51 Pegasi [source: Mayor and Queloz]. Since then, others -- including the scientists of NASA's Kepler Mission -- have been on a quest to find more of these exoplanets, as they're called by astronomists. In particular, they aim to identify rocky, Earthlike orbs that are the within the so-called "Goldilocks zone" -- that is, just the right distance from their stars to have surface temperatures that would sustain liquid water, and thus at least make possible the development of life [source: Borucki].
Armed with state-of-the-art telescopes and other high-tech tools, astronomers are spotting new worlds at an astonishing rate. As of early 2012, Kepler's scientists, who've been scanning 150,000 distant stars in search of signs of planets orbiting them, have identified around 2,300 "candidates," or objects that may be planets [source: Brumfiel]. In late January 2012, they announced the discovery of 11 new planetary systems, including 26 confirmed exoplanets, which apparently range from possible rocky planets about one-and-a-half times the radius of Earth, to gas giants bigger than Jupiter. One star, Kepler-33, has a solar system of five planets, which range in size from one-and-a-half to five times the size of Earth [source: NASA].
But those discoveries may just be the tip of the iceberg. Kepler scientists estimate that there may be as many as 50 billion exoplanets in the Milky Way [source: O'Neill]. Joseph Catanzarite, an astronomer at NASA's Jet Propulsion Laboratory, told Space.com in 2011 that as many as 2 billion of them may be Earthlike in scale. "With that large number, there's a good chance life and maybe even intelligent life might exist on some of those planets," he added [source: Choi].
So, what instruments and techniques do scientists use to locate exoplanets, and how do they work?


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The U.S. presidential election left people around the world anxious about the future, but Apple CEO Tim Cook rallied employees yesterday saying we all have to keep moving forward.
In an email to employees, Cook told employees that "Apple's North Star hasn't changed." The Apple CEO invoked the late Martin Luther King Jr. in his note, saying, "We only do great work and improve the world by moving forward."
Check out the full email:
I've heard from many of you today about the presidential election. In a political contest where the candidates were so different and each received a similar number of popular votes, it's inevitable that the aftermath leaves many of you with strong feelings.
We have a very diverse team of employees, including supporters of each of the candidates. Regardless of which candidate each of us supported as individuals, the only way to move forward is to move forward together. I recall something Dr. Martin Luther King, Jr. said 50 years ago: "If you can't fly, then run. If you can't run, then walk. If you can't walk, then crawl, but whatever you do you have to keep moving forward." This advice is timeless, and a reminder that we only do great work and improve the world by moving forward.
While there is discussion today about uncertainties ahead, you can be confident that Apple's North Star hasn't changed. Our products connect people everywhere, and they provide the tools for our customers to do great things to improve their lives and the world at large. Our company is open to all, and we celebrate the diversity of our team here in the United States and around the world — regardless of what they look like, where they come from, how they worship or who they love.
I've always looked at Apple as one big family and I encourage you to reach out to your co-workers if they are feeling anxious.
Let's move forward — together!
Best, Tim


text: Greetings, The *SciPy 2007 Conference on Scientific Computing with Python* early registration deadline is July 15, 2007. After this date, the price for registration will increase from $150 to $200. More information on the Conference is here: http://www.scipy.org/ SciPy2007 The registration page is here: https://www.enthought.com/scipy07/ The Conference is to be held on August 16-17. Tutorial Sessions are being offered on August 14-15 (http://www.scipy.org/SciPy2007/ Tutorials). The price to attend Tutorials is $75. The Saturday following the Conference will hold a Sprint session for those interested in pitching in on particular development efforts. (suggestions welcome: http://www.scipy.org/SciPy2007/Sprints) Today is the deadline for abstract submissions for those wanting to present at the conference. Please email to abstracts at scipy.org by midnight US Central Time. From the conference web page: "If you are using Python in Scientific Computing, we'd love to hear from you. If you are interested in presenting at the conference, you may submit an abstract in Plain Text, PDF or MS Word formats to abstracts at scipy.org -- the deadline for abstract submission is July 6, 2007. Papers and/or presentation slides are acceptable and are due by August 3, 2007. Presentations will be allowed 30-35 minutes, depending on the final schedule." We're looking forward to another great gathering. Best, Travis


text:
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Under Armour, Inc. is an American company that manufactures footwear, sports, and casual apparel. Under Armour's global headquarters are located in Baltimore, Maryland with additional offices located in Amsterdam (European headquarters), Austin, Guangzhou, Hong Kong, Houston, Jakarta, London, Mexico City, Munich, New York City, Panama City (international headquarters), Paris, Pittsburgh, Portland, San Francisco, São Paulo, Santiago, Seoul, Shanghai (Greater Chinese headquarters), and Toronto.
Under Armour was founded on September 25, 1996 by Kevin Plank, a then 24-year-old former special teams captain of the University of Maryland football team. Plank initially began the business from his grandmother's basement in Washington, D.C.He spent his time traveling up and down the East Coast with nothing but apparel in the trunk of his car. His first team sale came at the end of 1996. From his grandmother's basement, Plank moved to Baltimore. After a few moves in the city he landed at his current headquarters in Tide Point.


text:
From an initial gathering of just fifteen speakers and seventy-five participants in 1983, we have grown to become the world's biggest public interest environmental law conference.
With assistance from keynoters, panelists, and participants alike, we plan to inspire a renewed commitment to collaboration and outreach among conference attendees. We expect the conference to enhance the success of environmental lawyers and to contribute to a more vigorous movement that resonates across society.
The Public Interest Environmental Law Conference is the premier annual gathering for environmentalists worldwide, and is distinguished as the oldest and largest of its kind. The Conference historically unites more than 3,000 activists, attorneys, students, scientists, and concerned citizens from over 50 countries around the globe to share their experience and expertise. The Conference is organized solely by the volunteers of Land Air Water (LAW), a student environmental law society at the University of Oregon School of Law, and is co-sponsored by Friends of Land Air Water (FLAW), a non-profit 501(c)(3) organization.
The four-day Conference in Eugene, Oregon, includes over 125 panels, workshops, and multi-media presentations addressing a broad spectrum of environmental law and advocacy. Topics include: forest protection and ecological restoration, grazing and mining reform, labor and human rights, air and water pollution, Native American treaty rights, globalization and "free" trade, environmental justice, corporate responsibility, marine wilderness, international environmental law, water rights and dam removal, oil and gas litigation, genetic engineering, and urban growth.
Each day of the Conference culminates with keynote presentations from preeminent activists, scientists, politicians, philosophers, and authors. Past keynote speakers include Robert Kennedy, Ralph Nader, David Brower, Terry Tempest Williams, Ward Churchill, Vandana Shiva, Paul Watson, Winona LaDuke, Gerry Spence, Ramona Africa, Paul Hawken, and several recipients of the international Goldman Environmental Prize.
The Conference has become an event full of energy, innovation, and inspiration for all of us involved in the environmental movement. Whether you are a seasoned Conference attendee or a first-time participant, we look forward to seeing you!
Past conference information, including brochures, can be found on the history page.
For more information, please browse our website or contact LAW.


text:
Automatically grab data from any site, perform complex searching tasks, manipulate information from the Web – all with just a few lines of code.
WebZinc .NET powers thousands of organizations throughout the world. It's at the heart of many new exciting business ventures, such as price comparison site, Kelkoo.co.uk, and news aggregator, Google News.
What exciting things will YOU do with that power… right now?
Derek Ferguson, Dot Net Journal says:
"Perfect. It'll save you days of programming. Five
lines of code and it worked!"
here to read more press extracts


text:
It's Black History Month and as both a professor and a lover of Blackness, Black things and Black people, I want us all to study up. Just make sure you don't enroll in The Willie Lynch School of Social Research. Now some of my pro-Black, head wrap rocking friends who are very passionate about Black history 28-29 days a year are nodding their heads right now because they're familiar with Willie Lynch and think I'm about to berate folks for taking up his ways. These are the alumni of that school I so desperately want to shut down.
For those who are unfamiliar, there is a notorious letter- "How to Make a Slave"- that was said to have been read by a slaveholder named Willie Lynch on the bank of the James River in 1712. The document explains how slaveholders should keep the various enslaved Africans of their plantations at odds with one another to ensure that they are never able to revolt and to keep the psychological chains on their "property" as tight as the physical ones. The colloquialisms used and the improbability that someone would have ever presented such a plan that effectively predicted the long-term effects of slavery (for example, our issues with complexion) have long been used by scholars and researchers to refute the authenticity of the document. But you can still find copies of it and even films devoted to explaining how it manifested in Afrocentric bookstores across the country.
The Willie Lynch myth is just one example of the lazy "research" we tend to do online about our community, forward to others or, worse, try to convince our children of. If we want to Black history to be known, felt and understood, we as adults have some work to do!
Now the Willie Lynch School of Social Research has been matriculating students for a very long time and seems to have a booming enrollment. I remember being introduced to the school of research when I got forwards that all the Black Stamps were going being destroyed, that the first president of the US was Black, and the Statute of Liberty was a gift from France and the original model was a Black woman. While these are compelling and shocking revelations, all are false. History can be empowering but all too often we're given bad information and it spreads so fast it cloaks us from the truth.
As it was said, "A lie can be halfway around the earth before the truth gets its shoes on." The other day in one of my college classes I was stunned by the number of students who had no idea who Carter G. Woodson was, but immediately afterwards I was reminded why Black history month is still essential. People of African descent have made some of the most amazing contributions to this world, but they are made invisible by whitewashed curricula (there is even an ongoing fight to keep Arizona from banning ethnic studies) that eliminates the value of people of color all together; many of us have responded by attempting to aggrandize our achievement so it looks as if only Black folks have contributed to the world. The truth, like Carter G. Woodson intended for us to learn, is somewhere in the middle. Knowledge is power, but only if we are using our knowledge to transform how we see ourselves and how the world sees us. One of the central values of history is to tell us what was, so we know what can, and what should not be in the future.
Sometimes our histories and herstories are hidden and need to be unearthed, but other times we can spend our time spinning partial truths. Whenever I teach about the Willie Lynch Letter in my Black Studies classes inevitably students fight hard and ask, "Well what if some of it is true? Doesn't that make it important?" Important? Sure. Accurate? Not at all. I'm reminded of my grandmother's words, "A half truth, is a whole lie." As young Black folks look to us for inspiration and information the least we can do is dig a little deeper. You don't have to be Black Studies professor to dig deeper. Yes, I know the forward button is right there, but snopes.com and google.com are mere clicks away also.
In just the past twenty years, technology and our access to information have increased dramatically. Our techniques of interrogating and delivering this information to our children must also develop. I can recall growing up and seeing(space) the Budweiser Great Kings and Queens of Africa program, and thinking "what's this got to do with what's happening outside my window"? The process of sharing history must be greater than bombarding our children with facts and global trivia. Imagine if we shared our own families' stories of struggle and triumph. What if we spent time connecting the dots between a great past and showing them how they could make a great present. Reject apathy and ignorance, but don't sign up for that Willie Lynch online class either!
Dr. R. L'Heureux Lewis is an Assistant Professor of Sociology and Black Studies at the City College of New York – CUNY. His work concentrates on race, education and gender. You can follow him on twitter at @dumilewis or on the web at www.professorlewis.com


text:
Based on the 2006 animated film by Luc Besson, the game allows players to relive the fantastic adventure of young Arthur and his two pals, Selenia and Bétamèche, in their mission to save the Minimoys' world from destruction. The game incorporate Besson's entire Minimoy universe and its tiny inhabitants (just a couple of millimetres tall) with the richness and extraordinary visuals of the film. Gameplay revolves around the teamwork of the trio (Arthur, Selenia and Bétamèche): players can only progress by cleverly combining the three characters' skills. In solving mysteries and overcoming obstacles, players will realize that anything is possible when you work together.
Also known as: Arthur and the Invisibles, Arthur & the Invisibles, Arthur and the Minimoys
Release Region: United States
Release Date: January 10, 2007
Publisher: Atari
Release Region: United Kingdom
Release Date: February 2, 2007
Publisher: Atari
Release Region: Australia
Release Date: February 2, 2007
Publisher: Atari
Also available on: Game Boy Advance, Nintendo DS, PlayStation Portable, PlayStation 2, Wireless
Arthur and the Invisib... at IGN
Arthur and the Invisib... at GameSpy
Arthur and the Invisib... at GameStats


text:
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text:
|Zenyatta: "Am I not a woman and a horse?"
Setting aside the rather large problem regarding the network's confusion regarding the category "woman," the list is a rather bland summary of accomplishments. The biggest stories are not always the ones we want to hear - a real list of the biggest stories for women in sports would include a mix of the good and the bad. I've approached this from a journalism standpoint, and have forwarded a few of the stories that I think are most important. This is quite different from listing accomplishments of female athletes.
[Since publishing this, I wrote a mildly satirical post for The Guardian's "Comment is Free" page: ESPN makes mare's nest of women in sport. I think I do my best work in the comments section.]
- Mary Kom wins 5th women's world boxing championship. Indian women dominate the sport and are poised to bring the first Olympic gold medal to the country in the London Olympics.
- Two South African players charge national women's team coach with sexual harassment – accuse coach of prowling dormitory at night and dropping players from the squad who reject his advances.
- U Conn claims record for longest winning streak in basketball – Stanford claims honor of breaking 90 game run. Meanwhile the accomplishments of the individual athletes (most notably Maya Moore) are ignored in end-of-the-year awards for athletes.
- FC Gold Pride - possibly the best women's club team ever assembled - wins season, and folds: WPS is the most competitive professional women's soccer league in the world, but struggles to win sponsors and is overwhelmed by media blackout.
- Nigerian women's soccer team become first African [women's] team
of either genderto play in a World Cup Final – as the national association is swamped in scandal, their remarkable achievement goes unnoticed.
- Mexico beats the US women's national soccer team in a crucial World Cup qualifying match. Sends the latter to a desperate play-off with Italy, and initiates what fans hope will be an extension of the infamous border rivalry in the men's game to the women's game.
- Ines Sainz harrassed by New York Jets, international coverage of story revives sexist attitudes about women journalists and sports coverage. Brett Favre sends explicit pictures and texts to hostess working for Jets, given a slap on the wrist fine by the NFL.
- Serena Williams wins 4th Wimbleton singles trophy, breaks tournament record with 89 aces across her career. 13th title puts her 6th in list of grand slam champions.
- ESPN names horse as a top story in women's sports. We LIKE horses. That doesn't MAKE us horses.
BBC story on Mary Kom, 5 time Women's World Boxing Championship, from Manipur, India


text: Description Our duck zip-to-thigh bib overall is quilt-lined to keep you warm on the job site. Made of 12-ounce, 100% ring-spun cotton duck, it has a 100% nylon quilted polyester lining to waist and features ankle-to-thigh leg zippers with protective wind flaps. The chap-style double-front has cleanout bottoms that can accommodate knee pads and back-leg Cordura® kick panels add extra durability. Write a Review No reviews yet.


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Sunday, 13 January 2013
17 comments:
wasnt it glorious to see the sun- even f it was only for one day!ReplyDelete
- Briony Dawkins13 January 2013 at 09:04
Just beautiful! and you had sun this week! *Pines for Cumbria*ReplyDelete
Just beautiful! and you had sun this week! *Pines for Cumbria*ReplyDelete
Fresh air shot. love itReplyDelete
A pretty morning - looks like there was a nice sunny day to come.ReplyDelete
Looks like a fine day ahead? Wishful thinking, though.ReplyDelete
Beautiful, but it looks cold too...ReplyDelete
- Glitzy Gleam13 January 2013 at 10:44
very beautiful photo xxReplyDelete
Such a peaceful morning! :) xReplyDelete
Oh beautiful. And so lovely to finally see the sun. Have a lovely Sunday xxxReplyDelete
- countryidyll13 January 2013 at 13:35
I'm envious of all your beautiful views! Too flat here to have much of a vista.ReplyDelete
- coombemill13 January 2013 at 13:55
Lovely blue sky!ReplyDelete
Gorgeous. It has been so nice to finally see the sun!ReplyDelete
I want to come and live with you xReplyDelete
- MidlifeSinglemum13 January 2013 at 18:48
I will never tire of that view from your window, no matter what weather, what season, it's still stunning.ReplyDelete
That looks so peaceful! LovelyReplyDelete
what a gorgeous january day, can we have a bit of your sunshine?ReplyDelete


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Library Search
The NRFC Library is a collection of materials to build a knowledge base around fathers, fatherhood, and operating a Responsible Fatherhood program. It also houses all resources created by the NRFC, including fact sheets, PSAs, and past webinars.
Use the search options provided below to find resources that you are interested in.
This fact sheet describes the importance of play between parents and children and provides tips for effective play such as full engagement, tapping community resources to spend time as a family, and making time for one-on-one play. This product also gives suggestions for fun activities that…


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Giants & Dodgers Players Condemn Violence After Fan Beating
SAN FRANCISCO (CBS 5 / KCBS / AP) ― San Francisco Giants players in their orange and black emerged from the third-base dugout and walked to the mound as the rival Los Angeles Dodgers in blue did the same from the first-base side.
On a rare night when players from both teams addressed fans before first pitch, Giants reliever Jeremy Affeldt and Dodgers second baseman Jamey Carroll came together for a joint message: This rivalry must stay on the field, without violence and hatred.
The teams gathered on the pitcher's mound Monday night before their series opener at AT&T Park to make clear there should be no repeat of the events following their season opener March 31 in which longtime Giants fan Bryan Stow was assaulted outside Dodger Stadium and left in a medically induced coma.
KCBS' Tim Ryan Reports:
With heightened security at the waterfront ballpark, the teams took the field for a game dedicated to the 42-year-old Stow, a paramedic from nearby Santa Cruz and father of two.
"There's no room in this game for hatred and violence. It is about respect," Carroll told the sellout crowd, which applauded his remarks. "This is America's national pastime and let's keep it that way."
A photo of Stow showed on the main center-field scoreboard along with his two children as both teams removed their caps in a quiet moment of reflection.
Affeldt thanked fans for their generous financial and emotional support to help Stow and his family — then he spoke of the need for respect on both sides.
"I don't have to tell you about the Dodgers-Giants, it's one of the most storied rivalries in the history of the game but in honoring that rivalry and honoring the Stow family, you have to remember when these two teams get on the field and play, we're competitive," Affeldt said. "But when the last out is made, that rivalry ends on the field, so please respect that."
The Giants presented former infielder Juan Uribe — now wearing the rival Dodger Blue — with his World Series ring from last year in a presentation on the field, two days after San Francisco's players received theirs. Uribe waved his cap when called out of the visitor's dugout to a standing ovation, then received hugs and handshakes from his former teammates before being handed his ring by managing general partner Bill Neukom.
San Francisco manager Bruce Bochy hoped that gesture would provide a positive sign to fans about sportsmanship.
"We're playing each other and we're competitive and rivals but let's leave it at that," Bochy said. "Our thoughts are with Bryan Stow. This shouldn't happen. We're hoping to send a message tonight so it doesn't become a bigger problem."
Dodgers center fielder Matt Kemp expressed sadness about what happened to Stow.
"That's a terrible thing what happened to that man," Kemp said. "It's a rivalry but it's not so serious to almost take somebody's life. This guy is never going to be same again over wearing the wrong jersey."
The Giants dedicated Monday's game to Stow, a paramedic. The team and Stow's employer, American Medical Response, collected money outside and inside the ballpark for a fund set up to help pay his medical bills.
The Dodgers tossed four baseballs to fans as they came off the field from batting practice — not a regular practice of the visiting team.
Monday's game marked the first meeting of the year played in San Francisco since Stow was severely beaten by two men in Dodgers gear in a stadium parking lot.
Stow has been in critical condition in a medically induced coma at Los Angeles County-USC Hospital since the attack. No arrests have been made despite a $150,000 reward.
The Giants and San Francisco Police Department increased the number of police officers on patrol both inside and outside the ballpark, officials said.
"We're going to have a zero-tolerance policy on public intoxication and combative behaviors," said San Francisco police spokesman Alvie Esparza. "We want fans to come to the ballpark and enjoy the game, but they have to do it in a civilized and respectful manner."
Esparza said the police presence at the Giants-Dodgers series would be similar to that of last year's World Series games.
The team and police officials encouraged fans to report any incidents of violence or unruliness in the stands through a text-messaging system ballpark security officials have set up.
"The thing in L.A., you love rivalries and you love playing here, but at some point it goes over the top," Dodgers manager Don Mattingly said before Monday's game.
Several fans nearby the ballpark said before the game they were optimistic there would be no further incidents.
"I think everyone can agree that what happened in L.A. was really screwed up, and we're hoping nothing happens here. It's good to see people out here wearing Dodgers uniforms," lifelong Giants fan Chris Swanson said at a nearby restaurant and bar. "It intensifies the rivalry, but I think everyone just wants to see a good game. Despite whoever wins, it's about the game more than what colors people are wearing."
In Los Angeles, baseball fans drove through Dodger Stadium on Monday, arriving in cars, on motorcycles and on bicycles to drop off cash, checks and good wishes for Stow's family.
Hall of Fame Dodger Tommy Lasorda told reporters in the stadium parking lot that he prays that Stow — a father of two — will come out of the coma so he can resume his life.
"This young man someday, I hope and pray, can walk into a ballpark again and enjoy the game," the 83-year-old said.
As police review what happened and make changes, Los Angeles County Supervisor Mike Antonovich urged increased lighting in parking lots, increased security in the stands and parking lots, a stringent alcoholic beverage limit and possibly a reduction in cup size.
Michael Martin, a native of Los Angeles wearing a Brooklyn Dodger hat, stopped by to leave $100.
"I just wanted to show that Dodger fans are not like the two nuts that did this horrible thing. It's OK to cheer and boo at the stadium but this is atrocious what they did to this Giants fan," Martin said.
City Councilman Tom LaBonge said he would work with the city and county in an effort to make penalties more severe for "those who disrupt at public arenas, those who are idiots, those who are cowards, those who don't belong."
(Copyright 2011 by CBS San Francisco. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. Wire services may have contributed to this report.)
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I know I look squeaky clean and about as cool as most sit-com dads, but I do like tattoos. I have a few myself and so do others in my family. When choosing a tattoo, my philosophy is that you should choose wisely because you are, for the most part, stuck with that on your body forever more. Some people aren't so picky though. Based on seeing others, these are my top ten worst possible tattoo choices. In the comments, tell me what your ideas are.
10. A corporate logo: I like a lot of products, but not so much I'd tattoo them on me. I've heard of people being paid to have a logo tattooed on them. No thanks. What if in ten years you find out that company has been poisoning people or making hamburgers out of puppies?
9. Someone's name: Through a job I once had, I knew a couple that had each others names tattooed on their necks, so of course they broke up. Maybe your name and home address with the phrase "If found, return to:" just in case you pass out somewhere.
8. Face tattoo: The news came out yesterday that Justin Bieber got a face tattoo. Of course he did. He's a moron. His is just a tiny cross beneath his eye, but others have certainly done much worse on their faces.
7. The permanent makeup: Sounds like a great idea right? Never have to put eyeliner or lipstick on again! I don't get it. I think 99% of women look better without makeup.
6. A band name: Unless it's The Beatles, can anyone think of any band right now that we'll still consider brilliant 40 years from now? Who's got that One Direction tattoo? Anyone?
5. A cartoon character: I like SpongeBob as much as the next guy, but I'm pretty sure that when I'm 80 I'm not going to be into Scooby Doo, or SpongeBob, or Batman as much as I was when I was young. Also, when I'm 80 my grandchildren will wonder who all those weird characters on me are.
4. The bar code: The first time I heard of some one getting a bar code tattooed on the back of their neck I thought it was hilarious. Outside of that first dude, the rest of the people that did it are stupid and unoriginal.
3. A ghost shaped like a penis: The last time I got a tattoo, I asked the artist what was the stupidest tattoo anyone had ever requested from her. Yes, a ghost shaped like a penis. She showed me a picture.
2. The WordPress logo: I'm pretty sure that even if I got a WordPress tattoo and posted a picture of it on my blog every day for a year, I'd still never get Freshly Pressed. Jerks. If they did offer to Freshly Press a post of my choice from my blog if I get a WordPress tattoo…yes, I'd do it.
1. The neck tattoo: Not only do I imagine that the neck would be a painful place to get a tattoo, but unless you're willing to wear a turtleneck, that neck tattoo will be the first thing anyone notices about you. That's why Steve Jobs always wore a turtleneck. He was hiding an Apple tattoo he had gotten when he was drunk. It's possible I just made that up.
So those are my ideas for the top ten worst possible types of tattoos. What are yours? Do you have tattoos? Do you like tattoos? Do you hate tattoos? Is there one you're dying to get? Do you have one you regret?
Have a great Tuesday! ~Phil


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People spent the twentieth century obsessed with the future. We created technologies that would help connect us faster, gather news, map the planet, and compile knowledge. We strove for an instantaneous network where time and space could be compressed. Well, the future's arrived. We live in a continuous now enabled by Twitter, email, and a so-called real-time technological shift. Yet this "now" is an elusive goal that we can never quite reach. And the dissonance between our digital selves and our analog bodies has thrown us into a new state of anxiety: present shock.
Dimensions : 5.3 X 0.9 X 8.0 inches | 0.55 pounds


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STORage Maintenance
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The IETF IPS (IP Storage) and RDDP (Remote Direct Data Placement) working groups have produced a significant number of storage protocols (e.g., iSCSI, iSER and FCIP) for which there is significant usage. The time has come to reflect feedback from implementation and usage into updated RFCs; this work may include: - Implementation-driven revisions and updates to existing protocols (i.e., updated RFCs that match the "running code"). - Interoperability reports as needed for the resulting revised protocols that are appropriate for Draft Standard RFC status. - Minor protocol changes or additions. Backwards compatibility is required. Significant changes to the existing protocol standards are out of scope, including any work on version 2 of any of these protocols. Security for these protocols is based on the functionality specified in RFC 3723 (Securing Block Storage Protocols over IP); the working group does not intend to make major changes or updates to that RFC. Stability is critical to the usage of these protocols, so backwards compatibility with existing implementations will be a requirement imposed on for all protocol changes and additions. Note that this is a requirement for implementation compatibility - if it is the case that all implementations of a protocol have done something different than what the RFC specifies, it is appropriate for a new RFC to document what the "running code" actually does and deprecate the unused original behavior. List of work items: (1) iSCSI: Combine RFCs 3720 (iSCSI), 3980 (NAA names), 4850 (node architecture key) and 5048 (corrections/clarifications) into one draft (3720bis), removing features that are not implemented in practice. This draft should be prepared so that it could become a Draft Standard RFC, but the Working Group has decided not to advance it to Draft Standard status. (2) iSCSI: Add features to support at least SAM-4 (4th version of the SCSI architecture) in a backwards-compatible fashion, as iSCSI is currently based on SAM-2. This will be a separate draft from the iSCSI update in the previous item. The Working Group may add additional minor useful iSCSI features to this draft, including features from draft versions of SAM-5. The iSCSI MIB (RFC 4544) should be updated to provide SNMP support for new features as appropriate. (3) FCIP: IP Protocol number 133 was allocated to a precursor of the FCIP protocol in 2000, but this allocated number is not used by FCIP. The Working Group has documented the deployed pre-standard use of this protocol number in RFC 6172, and IANA has updated the registry entry to reference RFC 6172. (4) iFCP: The Address Translation mode of iFCP needs to be deprecated (SHOULD NOT implement or use), as there are significant technical problems with its specification, and moreover, only the Address Transparent mode of iFCP is in use. This will be done via a short draft that updates RFC 4172, and not via a complete rewrite of RFC 4172. The Working Group has deprecated iFCP Address Translation mode in RFC 6172 and made the corresponding changes to the iFCP MIB (originally RFC 4369) in RFC 6173. (5) RDDP MPA: Good support for MPI applications requires a small update to the startup functionality to allow either end of the connection to initiate. In addition, a couple of minor changes to RDDP connection setup are needed based on implementation experience. (6) iSER: Experience with Infiniband implementations suggest a few minor updates to reflect what has been done in practice. (7) RDMA Protocol: Experience with the rddp (iWARP) RDMA Protocol (RFC 5040) suggests that some minor extensions are needed, specifically, the addition of immediate data support and remote atomic operations. The Working Group is expected to maintain good working relationships with INCITS Technical Committee T10 (SCSI standards) and INCITS Technical Committee T11 (Fibre Channel standards) via overlaps in membership as opposed to appointment of formal liaisons. The liaison process (including IAB appointment of a liaison or liaisons) remains available for use if needed. Recent changes in INCITS rules have removed public access to some T10 and T11 standards documents that are expected to be needed for the WG's program of work. Arrangements have been made with T10 and T11 for IETF participants to obtain copies of specific standards their personal use in IETF work as needed; contact the WG chair(s) for details.