text:
|Publication number
|Publication type
|Application number
|PCT number
|Publication date
|Aug 15, 2000
|Filing date
|Dec 12, 1996
|Priority date
|Dec 12, 1996
|Fee status
|Publication number
|Chih-Shun Ding
|Original Assignee
|Ding; Chih-Shun
|Export Citation
|BiBTeX, EndNote, RefMan
|Patent Citations (10), Non-Patent Citations (6), Referenced by (22), Classifications (4), Legal Events (5)
|External Links: USPTO, USPTO Assignment, Espacenet
The invention relates generally to audio speaker drivers.
Recent decades have seen numerous developments in high-fidelity sound reproduction. Electronic and mechanical components made available to amplifier manufacturers have permitted the design of amplifiers that have better linearity and frequency response and lower distortion. Such amplifiers are smaller in size, less fragile, and less expensive. The audio sources (e.g. multiplexed stereo FM, digital compact disk, and compact cassette tape) are greatly improved over those previously available, and are dropping in cost. The electrical signals provided to the terminals of the speakers of a stereo sound system are, in present-day times and at modest cost, of a quality and fidelity that would have been unavailable to the consumer of two decades ago, except at prohibitive cost.
Those skilled in the art will appreciate, however, that one aspect of a high-fidelity sound system has remained stubbornly resistant to these improvements, namely the technology whereby the electrical energy of a sound system is converted to accoustic (airborne) energy: the speakers.
FIG. 1 shows the impedance of a electromagnetic speaker driver. It consists of three components: Re is the voice coil dc resistance, Lv is the voice coil inductance, and the parallel network of Lm, Cm and Rm is the motor impedance. The inclusion of Lm, Cm and Rm is a result of the energy conversion process between electric energy and mechanical energy in the electromagnetic speaker driver. To be more specific, the mass of the diaphragm causes Cm to appear in the driver's impedance, the friction for Rm, and the compliance of the diaphragm assembly for Lm. There are known formulae to relate the values of Cm, Rm and Lm to the mechanical parameters of the driver. If one puts a driver in a box, the measured impedance changes. There will be a network, which is related to the mechanical parameters of the box, appeared in parallel with the motor impedance. FIG. 2 show the added networks for closed-enclosure and bass-reflexive types of boxes.
The analysis of the frequency response in these systems under a voltage-source input signal can be done as in FIG. 3. Zb is the added impedance component from the speaker box. In the bass frequency region, the importance of Lv is very minor and hence omitted in FIG. 3. There is an equivalent mechanical system for the electrical system described in FIG. 3b. Alternatively, the analysis can be done on the mechanical system and result will be the same. Note that the dc resistance of the voice coil acts as part of the mechanical friction in the driver as seen from FIG. 3b.
In general, the bass response of a electromagnetic (boxed) speaker system (that is, the system including a electromagnetic driver (or drivers) and an enclosure in which the driver(s) resides) depends on the mechanical parameters of both the enclosure and the driver itself, as well as the voice coil dc resistance. Examples of the parameters for enclosure are the box volume and port resonance frequency (if the enclosure is ported or vented). Examples of the driver parameters are compliance, mass, and the friction of the diaphragm assembly. These parameters have to be carefully chosen so that the combined system provides good bass response. Very often the design procedure starts with some known parameters in the driver or the enclosure, then calculates the required values for the rest parameters. There are at least two implications here.
First, when one parameter (say enclosure volume) is altered during the design procedure, the drivers need to be redesigned so that they exhibit the new set of required parameters. Second, after one fixes some parameters and then calculates the required values for other parameters, these values may becomes unrealistic to implement mechanically, or the efficiency of the speaker system becomes unacceptable.
Several apparatus have been proposed to address the above-mentioned problem. The first type of apparatus uses a derived signal, which is related to the movement of the diaphragm in the driver, as feedback signal so that the velocity of the diaphragm will exhibit desired characteristics in the frequency domain. For instance, in a closed-enclosure system, the velocity of the diaphragm needs to be inversely proportional to frequency (in the piston frequency region) in order to provide truly flat frequency response. Such a requirement (for the diaphragm velocity) is independent of any mechanical parameters. Therefore, the frequency response of the speaker system does not depend on the mechanical parameters of the enclosure or the driver. The major disadvantage of this type of apparatus is that it is only feasible when the desired velocity is a simple function of the frequency. The closed-enclosure speaker system can be one example. On the other hand, to produce flat frequency response in a bass-reflexive speaker system, the velocity is a complex function of frequency and the mechanical parameters of the enclosure and the driver. This type of apparatus becomes impractical for a bass-reflexive system (or any other ported or vented box system).
The second type of apparatus, in which the output impedance is a combination of a negative resistance and a complex reactance, tries to change the "apparent" mechanical parameters such that they are different from the actual mechanical parameters. In essence, such apparatus provides a mechanism that "changes the mechanical parameters of the drivers electrically". The objective of the negative output resistance is to cancel the dc resistance in the voice coil so that the other part of the output impedance (the complex reactance) can interact directly with the motor impedance and its equivalent effects are the changes of mechanical parameters. One example of these type of apparatus that portrayed in U.S. Pat. No. 4,118,600. That approach can be applied to various type of speaker systems, ranging from closed-enclosure to bass-reflexive systems. However, a major problem with that approach is that the dc resistance in the voice coil is highly dependent on the temperature and hence the result of cancellation is not guaranteed in practice. For instance, copper, which is the most commonly used material for voice coils, has a temperature coefficient about 0.2%/� F. In the bass frequency region, the signals sustain longer than those in the other frequency region. Combined with the fact that the hearing threshold of human ears in bass frequency region is typically quite high, there will be a significantly higher amount of electric energy dissipated in the voice coils. The result is that the frequency response depends on the voice coil temperature, and hence is not stable. A major problem with the system proposed therein is the negative output resistance. As will discussed below, the system according to the invention avoids this problem.
An approach to the temperature-shift problem is suggested in U.S. Pat. No. 4,980,920. The patent suggests a temperature compensation circuit to address this problem, but the result is hardly satisfactory in practice as issues such as thermo-coupling between the voice coil and the temperature sensor, and the linearity of sensor outputs, challenge the long-term stability of such a system.
An improved sound reproduction system employs an amplifier system and a speaker. The speaker provides two feedback signals, one indicative of the current through the speaker voice coil and a second indicative of the velocity of the speaker diaphragm. The velocity signal is provided via the first feedback path to an input of the amplifier of the amplifier system. In one embodiment, the current signal is provided by the second feedback path through a bandpass filter to the amplifier input. The velocity measurement may be derived from a second voice coil coupled to the diaphragm, or may be derived from a piezoelectric sensor coupled thereto. The current signal may be derived from the voltage drop across a resistor placed in series with the speaker voice coil.
Preferably the bandpass filter characteristics (and optionally the velocity-derived first feedback characteristics) are optimized with respect to the electrical and mechanical characteristics of the speaker and its enclosure. This matching may be accomplished by means of fixed components in an amplifier system that is dedicated for use with a particular speaker and enclosure. Optimally, however, the matching is accomplished so that the amplifier system is usable with any of a number of speaker/enclosure arrangements. A circuit card is provided with the speaker system, and electrical components in the circuit card are selected in relation to the electrical and mechanical characteristics of the speaker system. The circuit card is plugged into a connector at the amplifier system, and in this way the feedback coupling is optimized for the particular speaker system associated with that circuit card.
Stated differently, the objective of the present invention is to provide a driving apparatus for a speaker system so that the apparent mechanical parameters of the driver are different from the actual parameters without putting a negative resistance in the output impedance of the apparatus, in order to achieve excellent and stable bass frequency response. This objective is achieved using a combination of current sensing and notional signal feedback. That is, the signals correspondent to the current flow through the voice coil of the driver and movement of the diaphragm are put in the closed loop of the driving apparatus so that the equivalent effect of the arrangement is the change in the apparent mechanical parameters of the driver.
The invention will be described with respect to a drawing, of which:
FIG. 1 shows in schematic form an impedence model for a generalized audio speaker;
FIG. 2 shows the model of FIG. 1 with additional components modeling a speaker in an enclosure;
FIGS. 3a and 3b show equivalent circuits resulting from analysis of the frequency response of the system of FIGS. 1 or 2;
FIG. 4 shows in functional block diagram form an embodiment of the invention;
FIG. 5 shows an equivalent transfer function diagram for FIG. 4;
FIGS. 6a, 6b and 7 show equivalent circuits to FIG. 5;
FIGS. 8a and 8b show simplified embodiments of the system of FIG. 4;
FIGS. 9a and 9b shows embodiments of the invention employing DC feedback;
FIG. 10 shows an equivalent circuit for FIGS. 9a and 9b;
FIG. 11 shows an embodiment of the invention employing a DC servo loop;
FIGS. 12a and 12b show equivalent circuits for the system of FIG. 11;
FIGS. 13a and 13b show counterparts to FIGS. 12a and 12b taking Lv into account;
FIG. 14 shows the response of a system according to the present invention;
FIG. 15a shows an embodiment of the invention in which a resistor is included in the velocity feedback path;
FIG. 15b shows an equivalent circuit for FIG. 15a;
FIG. 16a shows a generalized bandpass filter, and
FIG. 16b shows the decomposition of such a filter into distinct high-pass and low-pass filters;
FIG. 17a shows the high-pass filter of FIG. 16b;
FIG. 17b shows the high-pass filter of FIG. 17a after incorporating a DC feedback signal;
FIG. 17c shows the high-pass filter of FIG. 17a with a still different transfer function;
FIG. 18 shows the transfer function for the system of FIG. 11, in the special case in which Rs is omitted;
FIG. 19a shows the low-pass filter of FIG. 16b;
FIG. 19b shows the low-pass filter of FIG. 19a with a different transfer function;
FIG. 19c shows the low-pass filter of FIG. 19a employing a shallower slope of filter;
FIGS. 20a and 20b show in functional block diagram form embodiments of the invention employing a plug-in card;
FIG. 21 shows in schematic form a prototype embodiment of the invention;
FIG. 22a shows a block diagram of complex impedence loading;
FIG. 22b shows a block diagram of complex impedence loading with voltage-controlled current sources;
FIG. 23 shows an equivalent system for a bass-reflexive configuration;
FIG. 24a shows a typical frequency response of a system without complex loading;
FIG. 24b shows a frequency response of a system with complex loading;
FIGS. 25a and 25b show two possible Bode plot combinations of Z and G;
FIGS. 26a and 26b shows possible circuit implementations corresponding to the two cases of FIGS. 25a and 25b;
FIG. 27a shows the apparatus of prior art U.S. Pat. No. 4,118,600;
FIG. 27b shows the described apparatus in contradistinction to FIG. 27a;
FIG. 27c shows a design example corresponding to the described system of FIG. 27b;
FIG. 28 is a circuit design resulting from two simplification schemes;
FIG. 29a is a circuit design applying all of the simplification schemes;
FIG. 29b is a circuit design eliminating G and using an op amp;
FIG. 29c is a circuit design using a capacitor between the input resistors to implement G;
FIG. 30a shows a frequency response diagram without the lowpass filter implemented by G;
FIG. 30b shows a frequency response diagram implemented in G;
FIG. 31a shows a direct-drive design which does not use sensing coil or current feedback;
FIG. 31b shows an alternative direct-drive design which does not use sensing coil or current feedback;
FIG. 32a shows a circuit using solely current feedback in a second design example;
FIG. 32b shows in contradistinction a current-feedback circuit according to the prior art;
FIG. 33a shows a circuit using solely current feedback in a third design example; and
FIG. 33b shows in contradistinction a current-feedback circuit according to the prior art.
FIG. 4 shows one embodiment of the present invention. The speaker driver 40 has two voice coils 41, 42. Coil 41 is used as the load for the amp 43 to convert electrical energy to mechanical energy. The second voice coil 42 is for deriving the motional (velocity) feedback signal. The voltage applied to the driving voice coil 41 has two components: one is the drop across the dc resistance of the voice coil 41 and the other is the induced voltage caused by the movement of voice coil in the static magnetic field of the speaker. The latter is exactly the voltage drop across the motor impedance in FIG. 1. (This is statement is, of course, an approximation as the inductance of the voice coil 41 also contributes part of the induced voltage. However, let us now assume Lv is very small and can be ignored.) Assume that these two voice coils 41, 42 are closely coupled (for instance, wound on the same former or coilform) so that the induced voltage at the sensing voice coil 42 Vs is a constant factor Ks of the induced voltage of the driving voice coil 41 Vd. That is,
Vs =Ks �Vd
Moreover, if R3 is very high so that very little current is drawn from the sensing voice coil 42, then the voltage drop due to the dc resistance of the sensing voice coil 42 can be ignored. Therefore the voltage drop between the two terminals of sensing voice coil 42 is exactly Vs.
FIG. 5 shows the block diagram of FIG. 4. Let us assume the gain of the bottom inverter 44 in FIG. 4 is -1, therefore the sign of 1/R2 45 in FIG. 5 is negative. Furthermore, the transfer function 46 of the basspass filter 45 is assumed as shown in FIG. 5. If the amp 43 has infinite gain, then the input to the amp 43 should be zero, that is, ##EQU1## where I is the current flow through the driving voice coil 41.
Equation (4) shows that the system amplifies the input signal 47 with a magnitude of basspass characteristics, drives the motor impedance Zm of the driving voice coil 41 and has an output impedance equivalent to a parallel network consisting of R, L and C components as shown in FIG. 6. Note that Vd =Zm I.
The values of the components in FIG. 6 are as follows: ##EQU2## If I expand Zm in FIG. 6b, I get FIG. 7.
As implied in FIG. 7, Zp can be combined with Zm so that the system acts as if the driver has a different set of parameters. More importantly, this is done without using a negative resistance in the output impedance.
The circuit in FIG. 4 can be made much simpler as will now be described.
In general the required value Rp in Zp (FIG. 7) is very small so that the transfer function of the bandpass filter has real-value poles, that is ##EQU3## This reduces the circuit of FIG. 4 to the one of FIG. 8a. If only Cm and Rm need to be modified (that is, only Cp and Rp need to be in Zp of FIG. 7), then the circuit can be simplified to that of FIG. 8b. It will be appreciated, however, that these are very ideal cases. When one apply the techniques described here to real-world speaker drivers, at least two issues need to be considered: (1) dc offset voltage of the amp 43, and (2) the impact of Lv on the frequency response.
As may be appreciated from FIG. 8a, there is no DC feedback, as a result of which the system is not stable at DC. FIG. 8b does have DC feedback, so does not present this problem. There are at least two solutions here. First, one may add a DC feedback loop either from the current sensing resistor (FIG. 9a) or from the amp's output (FIG. 9b). Either way Zp is no longer a network of three components as modeled in FIG. 7. FIG. 10 shows the new Zp, which may be compared with that of FIG. 7.
The impact of Cd and Rd on frequency response can be minimized by using higher value of Rk in FIG. 9.
Another solution to the DC stability issue is to add a DC servo loop in the system. One possible configuration is shown in FIG. 11. The equivalent circuit of FIG. 11 is shown in FIG. 12a.
A potential problem with DC servo loops is the possibility of low-frequency oscillation. The equivalent circuit at very low frequency is shown in FIG. 12b, which is an LC network with no damping resistor. The remedy is to add a serial resistor to Cs in FIG. 11 so that the equivalent circuit becomes similar to FIG. 10.
Another potential problem (from Lv) also is addressed. The voltage drop across Lv is supposed to be part to the induced voltages Vd and Vs. Previous analysis ignores it because we assume its effect is very small. If the analysis is to be more general, however, it is necessary to consider the case in which its effect is not small. (Experience shows that it is not easy, nor cheap, reduce the value of Lv.) The impact of Lv to frequency response is restricted to high frequency. FIGS. 13a and 13b shows the equivalent circuit with Lv considered.
FIG. 14 shows the actual response of a system employing the present invention. The fc in FIG. 14 is the cut-off frequency of the speaker system. The peak at fp is caused by Lv, Cm and Cp. Another impact of Lv is the increased distortion at frequencies nearby to fp. This is because Lv is not a constant value. As a matter of fact, it is the major source of distortion at high frequency.
One investigator has addressed this problem by a particular current-drive technology. As Lv changes, fp also changes. Translating it to time domain, it means that the distortion is significantly increased around fp and above.
One solution to this problem is using two drivers in one box: one facing inward and one facing outward. This arrangement can cancel the odd-order harmonic distortion. For the even-order harmonic distortion, there is little one can do without radical change in the driver mechanical structures. Another possibility to reduce the impact is putting a resistor in series with the Zp in FIG. 7 so that the peak at fp is reduced. The problem is that, in the circuit of FIG. 8, it is very difficult to include exactly one resistor. One approach is that of FIG. 15a. FIG. 15b shows the equivalent circuit.
As will be appreciated by those skilled in the art, there are engineering trade-offs. Of course those skilled in the art can devise obvious variants of the embodiments shown here, all of which are intended to be encompassed by the invention as defined by the claims that follow.
The concept of impedance loading, as I have demonstrated here, can be extended. Let me define the loading in FIG. 7 as simple impedance loading, and the loading in the other figures as complex impedance loading. The impact of the complex impedance loading is that the frequency response could deviate from the ideal cases (simple impedance loading). This characteristic is very helpful as one can implement (part of) the filtering function required to cross-over to high frequency speaker driver using complex impedance loading. A computer program can be very helpful in tabulating all possible combinations of values for each commonly used alignment.
The derivation of the motional feedback signals will now be described. Many mechanisms have been proposed for derivation of the motional feedback signals. In the preferred embodiment, the driving and sensing voice coils are wound on the same former and closely placed. It is the cheapest way to do it and is commercially available. In these cases, the velocity signal is derived. Alternatively, one can use piezo-electric accelerometers, in which case the derived signals are the acceleration of the diaphragm, rather than the velocity, in which case the system of the present invention must be modified accordingly. In FIG. 4, for example, either the bandpass filter is changed to a high-pass filter, or the feedback resistance is replaced by an inductance. Either way, the network can still be decomposed, and what changes is the precise nature of the piezo feedback loop. Yet another approach is simply to take the piezo output and convert it to a velocity signal, for example through integration.
As will be appreciated, what is provided is a system offering compact-sized bass reproduction speakers, in which the required mechanical parameters are difficult to implement mechanically. Improved bass response is provided. Such a system offers its benefits especially with car (automotive) stereo systems and home theater systems. One advantage is the simplicity of the apparatus compared with other prior art approaches.
Returning to equation 9 I have: ##EQU4## The denominator is the impedance of the feedback network for the current signal and the system input signal (for example the circuitry 62 in FIG. 8a); the numerator is the impedance of the feedback network for the velocity signal (for example circuitry 63 in FIG. 8a). In FIG. 16, the high-pass filtered is assigned to the current feedback signal and low pass is assigned to the velocity feedback signal. Alternatively, one can assign the low pass filter to current feedback signal and high-pass filter to motional feedback signal. In the following, we limit our discussion to the filter assignment described in FIG. 16 as the other case is similar. In other words, the bandpass filter (for example filter 45 in FIG. 4) is decomposed into distinct filters.
In one variant, if a=0 in the bandpass filter, the velocity feedback network can be replaced by a signal resistor.
In another variant, if c=0 in the bandpass filter, the current feedback network can be replaced by a single resistor.
I refer to the technique described above as simple impedance loading. In practice, one may want to modify this technique to resolve real-world problems. For instance, in simple impedance loading, I assume that the impact of voice coil inductance is negligible. When this inductance is large, it adds a lowpass characteristic to the system as depicted in FIG. 14 and the whole system exhibits a bandpass characteristic. One may want to control the Q value of the upper cut-off frequency so that the system has a smoother response. Or one may want to control both upper cut-off frequency and its Q so that the system exhibits a desirable crossover characteristic. In the following, I will describe a scheme, called "complex impedance loading," to achieve this goal. I will assume that the system utilizes a bass reflexive configuration. Other enclosure configurations, such as closed-enclosure, can be similarly considered.
I first show the block diagram of complex impedance loading in FIG. 22a, and then derive the transfer function of the system in terms of the transfer function in each block. FIG. 22a is modified from FIG. 8(a). The shaded boxes in FIG. 22a are two-port networks (either active or passive). They are essentially voltage-controlled-current-sources as shown in FIG. 22b. For the sake of simplicity, we that assume Re =1 ohm, the gain of the amp is infinity, and the sensing voice coil exactly reproduces the induce EMF on the voice coil inductance and the motion-induced EMF. As a result I have: ##EQU5## The system is equivalent to one that drives the motional impedance of the speaker with a voltage source of -(Zs /Zg)Vin, through an output impedance network of Za /ZI. The major difference between this scheme and simple impedance loading is that, in the latter, Zg is simply scale-up or scale-down of ZI. I rewrite (1) as:
GVin =ZI+Vs
where G=-Zs /Zg and Z=Zs /ZI.
For a bass-reflexive configuration, the equivalent system is shown in FIG. 23.
The acoustic output of the system is calculated as the voltage drop across Lb, multiplied by s (in the context of a Laplace transformation). I first derive the impedance of the subnetwork comprising of Lm, Cm, Rm, Lb, and Cv (which we refer to as the motional impedance subnetwork), and then the voltage drop across this subnetwork. Then I calculate the dividing ratio of Lb in the divider network of Lb and Cv. By multiplying the voltage drop and the dividing ratio, we can compute the voltage drop across Lb and multiply it by s to get the acoustic output of the system as described next. The impedance of the motional impedance subnetwork is: ##EQU6##
I will simplify the above expression as: ##EQU7## where A=Rm Lm, Nm (s)=Lb Cv s2 +1, and Dm(s)=(Rm +Lm s+Rm Lm Cm s2) (Lb Cv s2 +1)+Rm Lm Cv s.
Note that, Nm (s) and Dm (s) are second- and fourth-order, respectively.
Next, I assume that Z, which is the output impedance in the complex loading scheme, is written as: ##EQU8## Therefore the voltage drop on the motional impedance subnetwork is: ##EQU9## The dividing ratio of Lb in the Lb, Cv subnetwork is ##EQU10## Therefore, the acoustic output of the system is: ##EQU11##
One can easily verify that, when Lv is 0, G is a constant, and Z is pure resistive, the overall system exhibits a 4th order high-pass characteristic, just as what an ordinary bass-reflexive system should be, If Lv is nonzero, G is a constant, and Z is pure resistive, the system becomes a 5th order band-pass: 4th order high-pass and 1st order lowpass. However, this is not a very desirable result. FIG. 24a shows a typical frequency response of a system without simple or complex impedance loading. The objective of the complex impedance loading system is to control both high-pass and lowpass characteristics so that the system is useful over a wider frequency range, as shown in FIG. 24b.
In equation (11), the parameters that will affect the overall system response are:
1) Nz and Dz : One can increase the order of one of these two terms, or both.
2) G: Previously, I have assume that the input is a constant voltage source, that is, G is some constant. If I allow G to exhibit frequency-dependent, or filtering, characteristic, I can have more flexibility in controlling the frequency response of the resulting system.
On the other hand, I do not want to make the above parameters so complicated that they add difficulties to the analysis. One arrangement that I describe is as follows:
1) Make Dz (s) 2nd order.
2) Make Nz (s)=sNz '(s), where Nz '(s) is 2nd order. Therefore Z can be written as: ##EQU12## 3) Make ##EQU13##
The response of the resulting system is 6th order: 4th order high-pass and 2nd order low-pass. Note the scope of the invention is not limited to the above arrangement. Other arrangements are also possible and can be analyzed similar to method that I use below.
When all the poles and zeros in G and Z are real numbers, the three shaded blocks in FIG. 22a can be implemented entirely out of passive elements. In this case, two possible bode plot combinations of Z and G are shown in FIGS. 25a and 25b. FIGS. 26a and 26b shows possible circuit implementations corresponding to these two cases.
The difference between the described apparatus and that proposed in U.S. Pat. No. 4,118,600 is summarized in FIG. 27:
1) The complex loading scheme drives the motional impedance directly, therefore eliminate the need of a negative output resistor used in the apparatus proposed in U.S. Pat. No. 4,118,600.
2) The voltage source in the apparatus proposed in U.S. Pat. No. 4,118,600 is proportional to the Zp, while in complex loading, the voltage source, determined by G, needs not to be proportional to Z. That is, the voltage source can be arranged independent of Z.
3) The Z in the complex impedance loading scheme can no longer be represented by a parallel network of RLC, as in the case of prior art U.S. Pat. No. 4,118,600.
In the following, we show a practical design example implementing complex impedance loading.
The driver is a 12-inch woofer. The enclosure is of bass reflexive configuration with internal volume of 74 liters. The Helmholtz resonator of the enclosure is tuned to 20 Hz. The measured component values in the motional impedance network are: Lv =1 mH, Rm =13 ohm, Lm =24 mH, Cm =2500 uF, Cv =7600 uF, Lb =8.3 mH. The design objective is to make the low-end cut-off frequency around 20 Hz(-4 dB) and high-end cut off frequency around 100 Hz with Q=0.7. The design result is: ##EQU14## where K is a constant that determines the gain of the system. The complete design is shown in FIG. 27.
In practice, simplifications on Z and G are possible. In the following, I will use design example 1 to illustrate the idea.
Simplification scheme (a): if the highest zero in the nominator of Z, (12), is located outside the frequency range I am interested in, e.g. 10-200 Hz, it can be replaced by a constant value of 89985. The G remains unchanged and the new Z becomes: ##EQU15##
Simplification scheme (b): if the lowest poles in the denominator of Z, (12), and G, (13), are located outside the frequency range I am interested in, e.g. 20-200 Hz, they can be replaced by expression s. The new Z and G are: ##EQU16##
Simplification scheme (c): if the lower zero (the term (s+180) in (12)) and higher pole (the term (s+172) in (12)) are very close, they can cancel each other out. The G remains unchanged while the new Z becomes: ##EQU17##
The above three simplifications can be combined. In the following, I will show some examples based on design example 1.
If I apply both simplification schemes (a) and (b), Z and G become: ##EQU18## The circuit design is shown in FIG. 28.
If I apply all the simplification schemes, the new Z and G become: ##EQU19## Three circuit designs are shown in FIGS. 29a, 29b, and 29c. FIG. 29b takes out G and implements it using another op amp (opamp2). FIG. 29c uses a capacitor between the input resistors to implement G. The invention intends to cover all designs that are similarly derived.
In this design, it is also interesting to note that how the flat response is achieved using such a simple circuit design, as shown in FIGS. 30a and 30b. FIG. 30a shows the response without the lowpass filter implemented by G, and FIG. 30b shows the filter implemented by G. In FIG. 30b the solid line is the filter implemented in G. The heavy line is the response of the composite system, shifted for clarity.
Another interesting case is when the combination of simplification scheme (b) and (c). In this case, the Z and G are:
Z=0.99+0.000011 s
In addition to the design that employs both sensing voice coil and current feedback, this combination also permit a direct drive configuration which does not use sensing voice coil or current feedback, as shown in FIGS. 31a and 31b.
While I have only shown three examples on combining ##EQU20## simplification schemes, the invention comprehends all possible combinations of simplification schemes (a), (b), and (c).
After proposing sensing voice coil and current feedback to implement the complex impedance loading scheme, I will show how one can also implement it using solely current feedback. In this case, the output impedance of the driving amp contains a negative resistance intended to cancel the voice coil dc resistance. In the following, I show the circuit designs example using solely current feedback. These designs may look like the one proposed in U.S. Pat. No. 4,118,600. To be able to differentiate the two, I also show the closest circuit designs that are proposed in U.S. Pat. No. 4,118,600.
Using the design example given in Design example 2, the circuit using solely current feedback is shown in FIG. 32a. FIG. 32b is the circuit design proposed in the prior art.
Similarly, the circuit using solely current feedback on Design example 3, is shown in FIG. 33a. FIG. 33b shows the circuit design proposed in the prior art.
The complex loading scheme can be regarded as a system with a bandpass or low-pass filter implicitly built-in using only one amp. Moreover, in most cases the shaded boxes in FIG. 22a can be implemented out of passive components. As a result, one can easily tailor the frequency response to suit one's crossover requirement. In the following, I will consider a multi-driver system that consists of at least two separate modules: one for bass, using the scheme described herein, and the second module for higher frequency, which will be referred to as the midrange module. Furthermore, I assume that the frequency response Tm (s) of the midrange module is a 2nd order, that is ##EQU21##
My goal is to design the frequency response of the bass module such that the composite system response (including the midrange module) is a flat all-pass. In this case, the frequency response Tb (s) of the bass module (ignoring the terms for the bass response) should be: ##EQU22##
To achieve the above frequency response described by Tb (s), one can design the Q and fp value of the high-end cut-off frequency of the complex impedance loading system such that it follows the following transfer function: ##EQU23##
After I come up with the G expression, I can modify the G by multiplying it with (qs+r), and some gain-control constant K', that is:
G'=K'G (qs+r)
Another way of implementing complex loading schemes is to directly modify the high-pass and low-pass filters of an existing simple impedence loading circuit to resolve real-world problems as described next. For instance, as mentioned previously, in order to ensure DC stability, I need to add DC feedback signal from the current signal (or the amp output). FIGS. 17a, 17b, and 17c show the possible new transfer function of the high-pass filter after incorporating the DC feedback signal. In FIG. 17b (for the circuits in FIGS. 9a and 9b), the new transfer function is: ##EQU24## In FIG. 17c (refer to FIG. 11), the new transfer function is ##EQU25## In FIG. 11, the DC servo loop is different from the commonly seen ones (which has Cs only, no Rs). Adding Rs is to prevent a possible oscillation. FIG. 18 shows the transfer function if Rs is not included.
What are shown in FIGS. 17b and 17c is the filter only for the current feedback signal. The network connecting the system input and the amp still has the original high-pass characteristics.
The low-pass filter can also be varied. FIG. 19 shows two possible variations of the low-pass section. The main purpose for these variations is to reduce the resonance peak at fp in FIG. 14. In FIG. 19b, a zero is added to the network. The new transfer function becomes (refer to FIGS. 9a and 9b): ##EQU26##
Alternatively, although this is thought to be less workable, it might be proposed to reduce the declining slope to smaller than 6 db/octave using a multi-pole and multi-zero network.
It should be appreciated that in the system according to the invention, the positional or motional feedback is a negative feedback, and that the current feedback is also a negative feedback.
FIG. 20a shows an embodiment of the invention in which the speaker is distributed with a matched circuit card 70. Circuit card 70 has components 71, 72 associated with electrical/physical properties of the speaker. (In simpler embodiments the circuit card 70 has only one of components 71, 72.) The amplifier system (roughly, region 73 in FIG. 20) is generalized to work with a variety of different speakers. When a particular speaker is installed to the system, the plug-in card 72 is plugged in to connector 74. This permits component(s) 71 to be connected with circuitry 62, and permits component(s) 72 to be connected with circuitry 63. In this way the speaker and amplifier offer the benefits of the invention. In FIG. 20 the components 71, 72 are portrayed as resistors, but it should be understood that any of a number of different components, such as capacitors, inductors, or combinations of these, may be provided (in connection with appropriately arranged filters 62, 63) to customize the amplifier appropriately for the particular speaker being installed. It will also be appreciated that the wires 75 are depicted as four wires, but that some other number of wires would suffice depending on the particular circuitry 62, 63.
FIG. 20b shows yet another embodiment for use in a system according to the invention. In this embodiment a connector has a plurality of electrical contacts, said contacts including a first contact connected with the amplifier input via line 95, a second contact connected with the first voice coil's current sensing means via line 92, a third contact connected with the system signal input via line 94, and a fourth contact connected with the motional feedback sensor, in this figure a second voice coil, via line 93. Optionally a fifth contact is connected with the second end of the resistor 50 via line 91. In this way, a filter 90 may be connected with the connector. Its coupling of the second voice coil with the amplifier input defines a first feedback, its coupling of the resistor with the amplifier input defines a second feedback. It also couples the system signal input with the amplifier input, as a result of which an audio signal on the audio signal input is reproduced in the speaker. The filter 90 is matched to the physical and accoustical qualities of the speaker.
FIG. 21 is the schematic of a prototype that has been built. In this configuration only the mechanical mass and friction have to be modified. Additional components, namely capacitors 81, 82, and 83 are not required for the invention but provide better stability at high frequency. In this embodiment, the positional feedback is by means of a filter 84 which might best be characterized as a modified low-pass filter. A coupling capacitor 97 couples the input audio signal with the amplifier.
Those skilled in the art will appreciate that stated in its most general terms, the invention presents a way of providing improved bass response. To accomplish this end, first and second negative feedback paths are provided. The first negative feedback means couples the notional measurement means output with the amplifier input; and the second negative feedback means couples a current measurement means electrically coupled with the voice coil driven by the amplifier with the amplifier input. In the simplest possible embodiments, one or the other of the two negative feedback means includes a frequency characteristic correcting circuit which is set to have variable gain dependent on the frequency of the input signal. Lastly, complex impedence loading schemes are described to address the voice coil induction issues.
|Cited Patent
|Filing date
|Publication date
|Mar 23, 1977
|Oct 3, 1978
|Karl Erik Stahl
|Loudspeaker lower bass response using negative resistance and impedance loading
|Aug 17, 1979
|Jun 30, 1981
|Meyers Stanley T
|Sound reproducing system utilizing motional feedback and velocity-frequency equalization
|Jan 11, 1980
|Jun 15, 1982
|Ayers Richard A
|Sound reproduction system
|Oct 19, 1983
|Feb 25, 1986
|Velodyne Acoustics, Inc.
|Loudspeaker with high frequency motional feedback
|Oct 13, 1989
|Dec 25, 1990
|Yamaha Corporation
|Negative impedance driving apparatus having temperature compensation circuit
|May 27, 1988
|Jul 9, 1991
|Yamaha Corporation
|Dynamic loudspeaker driving apparatus
|Nov 27, 1989
|Feb 4, 1992
|Louis W. Erath
|Feedback system for a sub-woofer loudspeaker
|Jun 15, 1990
|Apr 27, 1993
|Yamaha Corporation
|Power amplifier adapter
|Apr 29, 1994
|Jul 16, 1996
|Miller And Kreisel Sound Corp.
|Dual-driver bass speaker with acoustic reduction of out-of-phase and electronic reduction of in-phase distortion harmonics
|May 23, 1995
|Dec 24, 1996
|Masushita Electric Industrial Co.
|Bass reproduction speaker apparatus
|K.G. Stahl, "Synthesis of loudspeaker mechanical parameters by electrical means: a new method for controlling low-frequency loudspeaker behavior" in J. Audio Eng. Soc. vol. 29, No. 9, pp. 587-596 (1981).
|K.G. Stahl, Synthesis of loudspeaker mechanical parameters by electrical means: a new method for controlling low frequency loudspeaker behavior in J. Audio Eng. Soc. vol. 29, No. 9, pp. 587 596 (1981).
|P.G.L. Mills and M.O.J. Hawkford, "Transconductance power amplifier systems for current-driven loudspeaker" in J. Audio Eng. Soc. vol. 37, No. 10, pp. 809-822 (1989).
|P.G.L. Mills and M.O.J. Hawkford, Transconductance power amplifier systems for current driven loudspeaker in J. Audio Eng. Soc. vol. 37, No. 10, pp. 809 822 (1989).
|P.G.L. Mills and M.O.J. Hawksford, "Distortion reduction in moving-coil loudspeaker systems using current-drive technology" in J. Audio Eng. Soc. vol. 37, No. 3, pp. 129-148 (1989).
|P.G.L. Mills and M.O.J. Hawksford, Distortion reduction in moving coil loudspeaker systems using current drive technology in J. Audio Eng. Soc. vol. 37, No. 3, pp. 129 148 (1989).
|Citing Patent
|Filing date
|Publication date
|May 28, 1999
|Jan 8, 2002
|3Com Corporation
|Transfer function implementation using digital impedance synthesis
|Dec 22, 2003
|May 30, 2006
|Tymphany Corporation
|Mixed-mode (current-voltage) audio amplifier
|Aug 14, 2003
|Aug 8, 2006
|Quantum Applied Science & Research, Inc.
|Low noise, electric field sensor
|Oct 16, 2002
|Aug 21, 2007
|Audio Products International Corp.
|Position sensor for a loudspeaker
|Mar 26, 2010
|Mar 19, 2013
|Harman International Industries, Incorporated
|Motional feedback system
|Apr 30, 2001
|Oct 31, 2002
|Maximilian Hobelsberger
|Electrodynamic transducer with acceleration control
|Oct 15, 2002
|Apr 17, 2003
|Hlibowicki Stefan R.
|Loudspeaker with large displacement motional feedback
|Oct 16, 2002
|May 8, 2003
|Hlibowicki Stefan R
|Position sensor for a loudspeaker
|Apr 16, 2002
|Oct 16, 2003
|Chih-Shun Ding
|Motional feedback for a speaker system
|Aug 14, 2003
|Apr 15, 2004
|Krupka Michael Andrew
|Low noise, electric field sensor
|Aug 7, 2003
|Feb 10, 2005
|Tymphany Corporation
|Audio reproduction system for telephony device
|Aug 7, 2003
|Feb 10, 2005
|Tymphany Corporation
|Process for position indication
|Aug 7, 2003
|Feb 10, 2005
|Tymphany Corporation
|Position detection of an actuator using infrared light
|Aug 7, 2003
|Feb 10, 2005
|Tymphany Corporation
|Calibration of an actuator
|Aug 7, 2003
|Feb 10, 2005
|Tymphany Corporation
|Method of measuring a cant of an actuator
|Aug 7, 2003
|Feb 10, 2005
|Tymphany Corporation
|Position detection of an actuator using a capacitance measurement
|Dec 22, 2003
|Jun 23, 2005
|Hench John J.
|Mixed-mode (current-voltage) audio amplifier
|Aug 7, 2003
|May 18, 2006
|Tymphany Corporation
|Audio reproduction system
|Oct 29, 2012
|Jul 11, 2013
|Thomas William Engel
|Vehicle alarm with protection against power source and wiring tampering
|Aug 6, 2004
|Feb 17, 2005
|Tymphany Corporation
|Audio reproduction system
|Aug 6, 2004
|Jan 18, 2007
|Tymphany Corp
|Audio reproduction system
|Jan 29, 2007
|Apr 17, 2008
|Blackfire Res Corp
|Streaming media system and method
|U.S. Classification
|International Classification
|Cooperative Classification
|European Classification
|Feb 13, 2004
|Fee payment
Year of fee payment: 4
|Nov 14, 2007
|Fee payment
Year of fee payment: 8
|Mar 26, 2012
|Maintenance fee reminder mailed
|Apr 17, 2012
|Surcharge for late payment
Year of fee payment: 11
|Apr 17, 2012
|Fee payment
Year of fee payment: 12


text:
Worlds in Danger Episode 6 by jmkrebs30Watch
©2013-2016 jmkrebs30
Here it is! Episode 6 of Worlds in Danger! Life issues have become a bit of a problem lately for me. Expect a lot of action in the next episode, because Sonic will get a new form. XD
Blitz? Wtf? Edit: How you do the glow when silver is controlling the object?
yesssssssssssss silverxblaze save the day X3
It's awesome. Why are all the emeralds and stars translucent though?
At the end...that's Dry Bowser!
I can see you've improved.
dry bowsah xD btw I hope life issues turn out alright for you
Will Blitz battle Merlow in the next episode?
Nope. The next episode is going to have a battle against Dry Bowser.
Did Blaze seriously fire a Kamehameha?
Nonetheless, a pretty good episode thus far.
Your certainly improving
Nice animation
nice done!
Attagirl, Blaze!
Don't you think, Josh?
Adding Cream? Nice touch.
Nice!Keep on going!
Is that who I think it is?
Great work!
This is AWESOME
P.S. I hope things turn out alright for you.
P.S. I hope things turn out alright for you.

subset: commoncrawl


text:
Dow Slides 207 Points; Crude Oil Cruises Up
NEW YORK—Stocks tumbled Tuesday following a mixed bag of corporate earnings and as hopes for a big solution to Europe's debt crisis waned.
The Dow Jones Industrial Average dropped 207.00 points, or 1.7%, to 11706.62. The losses snapped a three-day winning streak in which the blue-chip Dow rose more than 400 points.
The action followed reports that a Wednesday meeting of EU finance ministers was canceled, although a scheduled summit among European leaders seeking a way out of the debt crisis is still planned.
The scotched meeting increased concerns about whether Europe will be able to sign off on a plan to recapitalize euro-zone banks, beef up the euro zone's bailout fund and restructure Greece's debt.
"We are at a really critical juncture for the market," said Linda Duessel, equity-market strategist at Federated Investors. "People are starting to realize there's no silver bullet that can come from Europe."
The Standard & Poor's 500-stock index lost 25.14 points, or 2%, to 1229.05, led lower by sharp drops in financial and consumer-discretionary stocks. Each of the index's 10 sectors dropped.
The Nasdaq Composite fell 61.02 points, or 2.3%, to 2638.42. The losses pushed the technology-heavy index back into negative territory for the year.
The S&P 500 had gained 17% from its Oct. 4 low through Monday's close, amid broad hopes European policy makers will come up with clear solutions to the sovereign-debt crisis. Last week, German Chancellor Angela Merkel and French President Nicolas Sarkozy issued a joint statement promising a comprehensive plan to combat Europe's troubles.
"It's put up or shut up for Europe," said Nick Kalivas, vice president of financial research at MF Global. "Talk is cheap. We need to see something concrete."
Even as a promised package of some sort is still expected to be announced Wednesday evening, market participants are growing increasingly skeptical about what these plans will actually entail.
"People just don't know what to think," said Barry James, president of the James Advantage Funds. "Folks are just kind of frozen in place. They don't know what's going to happen politically, fiscally or monetarily."
Shares of 3M MMM -1.10 % led the Dow lower, falling $5.14, or 6.3%, to 77.04, after the conglomerate reported third-quarter earnings and revenue that fell short of expectations. The company also lowered its full-year outlook, noting a number of its customers reduced inventories in anticipation of slowing demand. 3M lopped 39 points off the price-weighted Dow.
Meanwhile, DuPont reversed earlier gains and finished down 1.15, or 2.5%, to 44.94. The decline came despite the chemical company reporting better-than-expected third-quarter earnings and revenue. It also increased its full-year earnings outlook.
Amazon.com AMZN -0.54 % dropped 10.46, or 4.4%, to 227.15 in the regular session. The stock fell another 12% in after-hours trading as the online retail giant's quarterly earnings and revenue results missed analysts' expectations.
European stocks were mostly lower, with the Stoxx Europe 600 down 0.7%, as investors remained cautious ahead of the summit. Asian markets were mixed. China's Shanghai Composite rallied 1.7%, but Japan's Nikkei Stock Average shed 0.9%.
In economic news, U.S. home prices rose modestly in August from a month earlier, due to seasonal factors. It was the fifth-straight monthly increase, according to the Standard & Poor's/Case-Shiller home-price indexes.
But consumer confidence faded this month, with data from the Conference Board reverting back to recessionary levels. The private research group said its consumer-confidence index sank to 39.8 in October from a revised 46.4 in September.
In corporate news, Netflix NFLX 4.28 % slumped 41.47, or 35%, to 77.37. The Internet video distributor reported disappointing subscriber numbers and said fourth-quarter earnings and revenue will be lower than expected. The stock, which traded above $300 in July, fell below $80 for the first time in 18 months.
United Parcel Service UPS 0.25 % reported earnings that were slightly above estimates and revenue that was in line with forecasts. The package-delivery company's shares dropped 1.52, or 2.1%, to 69.35.
Texas Instruments TXN 7.85 % ' results were better than expected, but the firm offered a disappointing outlook for the fourth quarter, prompting the stock to drop 72 cents, or 2.3%, to 30.97.
U.S. Steel X 7.70 % dropped 2.37, or 9.6%, to 22.40, after posting third-quarter results.
Write to Steven Russolillo at email@example.com


text:
5 things to know before your institution starts publishing on Medium.com
July 26, 2016
Perhaps we in higher ed should consider motivating students to graduate by focusing more on what they have left to do than what they have already done, argues Alexandra W. Logue.
July 25, 2016
The increasingly intense pressure on faculty members to get federal grants has produced many undesirable consequences in higher education, argue Gordon G. Gallup Jr. and Bruce B. Svare.
Recent Articles
July 26, 2016 - 3:00am
July 25, 2016 - 9:00pm
Recommending a political / information thriller set in the mid-21st century.
July 25, 2016 - 6:08pm
A new version of the blog.
April 3, 2007
Social networking sites pose risks for students and challenges for colleges that try to monitor them, write Sheldon Steinbach and Lynn Deavers.
April 2, 2007
Think it's impossible for educators to fight a popular magazine's irresponsible rating system? Look north, and you'll see it can be done, writes Indira Samarasekera.
March 30, 2007
Laurence Musgrove considers the role of music in the writing process.
March 29, 2007
Far from disappearing in the Age of Google, academic and research libraries remain an integral part of students' college educations, says Pamela Snelson.
March 29, 2007
Alan Contreras asks: How should a civilized society ensure that college-able young people are not thrown away because they are poor?
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text:
|Publication number
|Publication type
|Application number
|Publication date
|Jan 4, 1977
|Filing date
|Apr 30, 1975
|Priority date
|Apr 30, 1975
|Publication number
|Leon D. Held
|Original Assignee
|Held Leon D
|Export Citation
|BiBTeX, EndNote, RefMan
|Patent Citations (6), Non-Patent Citations (1), Referenced by (7), Classifications (8)
|External Links: USPTO, USPTO Assignment, Espacenet
This invention relates to magnetic tape reproduction apparatus, and more particularly to a device for directly indicating within a magnetic tape cartridge the individual programs currently being reproduced.
An increasingly large segment of the musical industry concerns recordings which are placed on a magnetic tape located within a cartridge for reproduction in the home or automobile in an appropriate magnetic tape reproduction apparatus. The conventional magnetic tape cartridge is generally rectangular on its top and bottom sides, with program indicia being located on its top side. However, when the tape cartridge is inserted within a magnetic tape reproduction apparatus, only a small portion of the cartridge protrudes from the reproduction apparatus, and as a consequence, all program indicia located on the cartridge is hidden from view.
The present invention provides for continual display of indicia regarding particular programs being reproduced from the magnetic tape cartridge while the cartridge is inserted within a reproduction apparatus. An opening is provided in the end of the tape cartridge and a program indicator shaft having at least four sides, with each side having thereon written information regarding the particular programs located on a particular track of the magnetic tape. A drive shaft extending along one side of the cartridge engages the program indicator shaft, the drive shaft being engaged through an aperture in the side of the tape cartridge by drive means located within the magnetic tape reproduction apparatus. The drive means is connected in parallel with the program indicator lights in the magnetic tape reproduction apparatus such that when the apparatus switches from one track of the magnetic tape to another, the drive means will rotate the drive shaft and program indicator shaft so that new indicia representative of the programs located on the newly selected track will appear through the opening. To initially synchronize the program indicator shaft with the program lights in the magnetic tape apparatus, a knurled knob is provided on the program indicator shaft for manual rotation thereof.
Other aspects and advantages of the invention will become apparent during the following detailed description, taken in connection with the accompanying drawings, and in which drawings:
FIG. 1 is a cross-section of a magnetic tape cartridge employing the apparatus of the present invention,
FIG. 2 is a front view of the tape cartridge,
FIG. 3 is a perspective view of the program read-out shaft,
FIG. 4 is a partial section view of the tape cartridge when inserted within a magnetic tape player according to one embodiment of the present invention, and
FIG. 5 is a partial section view of the construction of a bracket according to the present invention.
Referring now to the drawings, a magnetic tape cartridge is shown generally at 10. Although not illustrated in detail, the tape cartridge houses a magnetic tape 12 wound on a spool 14, with tape 12 guided by appropriate means such that it is available for reproduction by magnetic transducer heads positioned along end 16 of the tape cartridge.
To display the particular program located on a particular track of the tape contained within cartridge 10, a program indicator shaft 20 is employed. Indicia regarding the various programs is located on the four or more faces of read-out portion 22. Since there are four stereo tracks in an 8-track tape cartridge, each face of read-out portion 22 will carry the entire listing of programs for an appropriate stereo track, one such face being visible at a time, with rotation of the program indicator shaft upon change of tracks as will be further described. Program indicator shaft 20 also employs knurled knob 24 for preliminary adjustment of the program indicator shaft upon initial insertion of the tape cartridge within a magnetic tape player. Brackets 26 are employed to rotatably maintain program indicator shaft 20 within tape cartridge 10. To ensure precise alignment of the faces of program indicator shaft 20, brackets 26 can be octagon-shaped in cross section, with portions 28 and 30 of program indicator shaft 20 being, for example, diamond-shaped but of smaller cross-sectional size in order to allow rotation within brackets 26.
To display the particular programs located on readout portion 22 of program indicator shaft 20, end 18 of cartridge 10 is constructed as shown in FIG. 2. An opening 32 is positioned adjacent readout portion 22 to allow protrusion of knurled knob 24 therethrough as well as viewing of one side of readout portion 22. To drive program indicator shaft 20, a drive shaft 40 is employed. Drive shaft 40 is mounted for rotation within brackets 42, and engages program indicator shaft 20 with an appropriate worm gear arrangement, generally shown at 44.
Rotation of drive shaft 40 when cartridge 10 is inserted within a magnetic tape player is effected as shown in FIG. 4. A relay or solenoid 46 in parallel with the program light indicator of the magnetic tape player is mounted in the tape player and includes a push shaft 48 extending from the armature of solenoid 46. When activated, push shaft 48 extends through aperture 52 of the tape player, entering magnetic tape cartridge 10 through aperture 52 and engaging spider gear 54 of drive shaft 40 as illustrated. Each extension of push shaft 48 and consequent engagement of spider gear 54 of drive shaft 40 causes a 1/4 revolution of drive shaft 40 and program indicator shaft 20 (or other fraction corresponding to the number of indicator faces on shaft 20, e.g., 1/8 if an 8-track tape is not stereo). Since solenoid 46 is in parallel with the program light indicator of the magnetic tape player, solenoid 46 is actuated only when a new track of the magnetic tape located within cartridge 10 is being selected, and as a consequence, new program information located on readout portion 22 of program indicator shaft appears through opening 32 only when a new track is being played.
Often, when magnetic tape cartridge 10 is stored with other like cartridges, only end 18 will be visible. Therefore, I provide hinged flap 34 to identify the programs contained on the magnetic tape 12. Flap 34 is hinged at 36, and when closed, will cover substantially all of opening 32. Indicia indicative of programs located on all tracks of tape 12 is provided on flap 34, and is visible when flap 34 is closed over opening 32.
FIG. 5 illustrates one suitable construction of brackets 26. Bracket portions 26',26" are mounted on end portions 18',18", respectively, as illustrated. When end portions 18',18" are brought together, portions 26',26" form bracket 26 for mounting program indicator shaft 20. Brackets 42 are formed in a like manner.
It should be evident that various modifications to my invention may be made without departing from the spirit or essential characteristics thereof. For example, if a magnetic tape with more than 8 tracks is employed, or if only one track is utilized at any one time, program indicator shaft 20 can be modified to include more than four readout faces, with the rotation equipment modified accordingly to provide for less than a 90� rotation of the program indicator shaft for each change of track. The scope of the invention is indicated by the following appended claims, and all changes which come within the meaning and intent of the claims will, therefore, not depart from the true spirit and scope of the invention.
|Cited Patent
|Filing date
|Publication date
|May 4, 1967
|Oct 6, 1970
|Automatic Radio Mfg Co
|Tape player for playing cartridges with different numbers of tracks
|Jul 14, 1967
|Jan 5, 1971
|Tenna Corp
|Tape cartridge system
|Jan 12, 1970
|Nov 30, 1971
|Grundig Emv
|Cassette for magnetic tape or the like
|Oct 14, 1969
|Jan 4, 1972
|Ban Itsuki
|Endless magnetic tape playing time indicating apparatus
|Jun 20, 1966
|Apr 18, 1972
|Philco Corp
|Automatic controls for tape players of cartridge type
|Feb 4, 1970
|Dec 12, 1972
|Grundig Emv
|Tape recorder and cassette for magnetic tape
|IBM Technical Bulletin, Tape Cartridge, R. B. Johnson et al., vol. 9, No. 6, Nov. 1966, p. 576.
|Citing Patent
|Filing date
|Publication date
|Jul 19, 1976
|Mar 14, 1978
|Victor Marut
|Indicia display and audio storage cassette
|Nov 23, 1983
|Apr 21, 1987
|Walter Holzer
|Storage medium for electronic data processing
|Sep 24, 1986
|Feb 2, 1988
|Eastman Kodak Company
|Tape memory with integral disk index on reel
|Oct 11, 1988
|Mar 13, 1990
|Tokyo Electric Co., Ltd.
|Multiprinting thermal transfer ink ribbon cassette
|Jun 7, 1995
|May 27, 1997
|Haddock; Fred T.
|Dynamic digital identification of storage media
|Jan 19, 2005
|Feb 24, 2009
|International Business Machines Corporation
|Rotary information device for removable media
|Jan 19, 2005
|Jul 20, 2006
|Johnson James W
|Rotary information device for removable media
|U.S. Classification
|International Classification
|Cooperative Classification
|European Classification


text:
Skip to comments.Rep. Jackson Lee: Farm Bill Will Again Put Starving Children in the Abyss
Posted on 07/12/2013 11:27:17 AM PDT by Sub-Driver
Rep. Jackson Lee: Farm Bill Will Again Put Starving Children in the Abyss July 12, 2013 - 1:16 PM By Elizabeth Harrington
(CNSNews.com) Rep. Sheila Jackson Lee (D-Texas) railed against House Republicans on Thursday, saying separating the food stamp program from the farm bill will defeat starving children.
The only thing that this House will do when it votes today is defeat starving children, Jackson Lee said. It will again put starving children in the abyss of the uncaring attitude of my friends, who for the first time in decades are separating the heart line of the Farm bill, the nutrition program, the Supplemental nutrition program, the food stamps program.
The agricultural bill passed 216-208 after Republicans removed the Supplemental Nutrition Assistance Program (SNAP) from the measure.
I am glad to stand with the Democratic caucus and the Congressional Black caucus and others to be able to say hunger is silent, Jackson Lee said in a sometimes incoherent floor speech. Theres no one on this floor today, no child on that microphone standing over here telling you that their belly is protruding because they have not eaten.
There is no one on this floor today that goes to a summer program and did not eat because their breakfast program is tied to the school and theyre out of school and summer brings about hunger, she said.
Jackson Lee then appeared to say that the Department of Agricultures nutrition programs give $300 bills so parents can feed their children in the summer.
Theres no one that has told you that families have an extra $300 bill in the summer time to feed their children, she said.
(Excerpt) Read more at cnsnews.com ...
What does food stamps have to do with the farm bill anyway? And why do we need a farm bill to begin with?
This is indeed both Hugh and series. Where's the huge manatee?
The School Lunch Program and the Food Stamp Program were originally attached to the Farm Subsidy Program as a way to get rid of excess produce from American farmers. Certain agricultural products, which were heavily subsidized, were passed on to schools and poor people.
"Snork, izzadibble, chilren, razzadibgrab.
Slightly black cacus speaks up to remain silent,
while protruding bellies summer school!",
Jackson Lee said in a sometimes incoherent floor speech.
Sometimes incoherent ??
Stupid twit, this is America. If their bellies are protruding, it's because they eat too many Twinkies and Happy Meals, and instead of doing any chores or climbing trees, they sit in front of the idiot box all day.
If I understand the farm bill, we guarantee money to some farms and then we tell them they can't raise the price.............of milk for example.
The opposite of capitalism.
If this idiot wasn't around to provide comedic relief she would have to be invented.
Does she take "Dickhead" pills each morning?
When is the last time in this country when you have seen a child with an extended belly due to starvation?'
(Too many Big Macs, maybe, but hunger, no)
and, if such a child did exist, wouldn't the democrats be falling all over themselves to get pictures?
This from a moronic idiot who wants to bring 50 million foreigners here for the U.S. taxpayers to support. I guess she doesn't want American kids to starve alone. FUSJL. You can't import poverty and then sit around and whine about it.
According to the teachers at a teachers blog I've read, the teachers are now required to have every child return the free breakfast/lunch form, even if the parents have aleady said that they don't need or want the program. The parents have to write N/A or something on the form and return it, regardless. Which makes it quite simple for corrupt admins to change the form in order to get the money for children who don't use the program.
There's an abyss where they can put Democrats??
Why has no one mentioned this national resource of garbage disposal?
Can one see the flag on Mars from the bottom?
"This is indeed both Hugh and series. Wheres the huge manatee?"
Getting stuned.
Rep. Sheila Jackson Lee (D-Texas) I.Q.56
No, communists like her do which of course turns into more votes.
Pray for America to Wake Up
Instead of a single bloated, pork-laden farm bill, the GOP in the House is going to split it into two bloated, pork-laden farm bills. And at the end of the day, they will likely spend more that way than if they had passed the original bill.
Will Again Put Starving Children in the Abyss
Literally, right Sheila?? /s
I was raised on a farm. In church, we would here about people starving in Africa. Then a man from the government would come around to inspect our farm to guarantee that certain fields lay fallow, and he would give dad a check for those fields to remain unproductive.
My dad was a really smart man. I asked him to explain the contradiction to me, starving kids and getting paid not to grow food.
He couldn't.
Ms. Lee should instead tell her peeps that maybe if they got off their deada$$es and went to work they wouldn't have to depend on "mogibmedats" for their chirruns!
With his beeber, no doubt.
Is this the one who's hair looks like an air freshener in the back of an 86 El Dorado?
She Does....Looney Tunes
What does food stamps have to do with the farm bill anyway?
Because, DC said it is part of the farm bill...
And why do we need a farm bill to begin with?
See above answer..
Why even comment on the statements these morons make? All they do is continue to make fools out of themselves.
Is there a member of Congress who is more ignorant that this idiot (Hank Johnson excepted)? I have never heard one intelligent thing uttered from this Houston fashion plate's mouth. My God, can you fathom the low IQ's of the people who elected her and worse yet continue sending her back to Washington. It just boggles the mind.
"Sometimes incoherent". Understatement of the year.
I want to know why just because a female wants to get her groove on does the world need to shell out the money to feed the fruits of her endeavors? I am all for looking out for innocent children's welfare and I don't want to see any suffer, but the mindset that you can be reckless and have kids you can't afford because tax payers will have to pay has got to go!
Larn sumpin new eva day. Didn't know we had $300 bills.
While I don't doubt that this occurs, and occurs more frequently than we know, the district in which I teach requires all forms returned to avoid law suits. Baby mamas purposely don't fill out and return the forms so that they can sue when their babies don't get free meals. They claim that forms have been handed in when in fact they never were. By showing our records, including the N/A forms, it somewhat helps us cover our butts.
So, if I read this right, they were starving, but weren't in the Abyss. Wow!
I remember stories about farmers being paid not to grow.
I remember when a story chin in Cal wanted to charge less for milk than the government allowed. Gotta stick to the government price.
Best wishes
She could feed a village with her hypocrisy, it's so thick.
This was a stupid act by the GOP. If they were so concerned about principles, they wouldn't have passed the central planning, socialized farm bill either.
The Republicans would have been smarter to pass a food stamp bill first if they were going to separate the two.
Until the Republicans come up with a food stamp bill. This is going to look like the Republicans are completely against food stamps. And that will cost them a ton of votes.
Speak to the parents & extended family of these children...
...whose FIRST responsibility is to feed them and shelter them, etc,
Abyss: that which is between the ears of Sheila Jackson Lee.
>>Until the Republicans come up with a food stamp bill. This is going to look like the Republicans are completely against food stamps. And that will cost them a ton of votes.
No it won't. People on food stamps don't vote Republican. I say if the Rats want to buy those votes they should to use their own money.
You'd be surprised at how many Republicans are on food stamps thanks to our stupid trade policies that have outsourced our jobs.
But dey won't be runnin' dat rover past where dem astronauts landed!
"What does food stamps have to do with the farm bill anyway?"
IIRC the Food Stamp Program is administered by the Dept. of Agriculture.
Sheila Jackass Lee.
Delta has refused to fly her ass anywhere anytime. She thinks she is da queen, but she's merely an aberration that has been elected and re-elected by a gaggle of African-Africans.
The good lady needs to spend a few days as a checker in a grocery especially on the day the Food Stamp accounts get their monthly allotments. Last Wednesday was EBT day in my state and I witnessed grocery carts full of steaks, soda, cookies, chips and every manner of junk food all paid for with my taxes. The EBT patrons then wheeled their carts of free food to the Wine and Spirits department where I work and paid cash for cases of beer. Our beer sales spike on EBT day.
Well, there is Maxine Waters of LA, CA and also in CA are the Sanchez sisters. Also remember that HankJ is in the Cynthia McKinney Memorial Moon-bat seat from the Hotlanta, as bad as he is (and he is), he can't be worse than she was.
Remember, these people are in 'privileged seats' similar to England's old 'rotten boroughs'. By gerrymandering these districts, both parties find things to agree upon in the end results. As old Otto von Bismarck said ... it is ugly in the sausage factory!
Where are the parents of these "starving children"? Shouldn't they have some responsibility for THEIR children?????
Well, if they consider her to be representative of them, who am I to argue, lol?
Especially considering that said taxpayers often have to postpone having children until they are at least somewhat financially secure, while having to pay taxes all the while to help support those who consider it their "right" to breed like rabbits on the taxpayers' dime.
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Chatter: Kenya votes
Kenya goes to the polls for the first time since its violent 2007 vote, cardinals start talking about a new pope, there's hope for curing HIV, and (the royal) we are not well.
Chatter: Kenya votes
Kenya goes to the polls for the first time since its violent 2007 vote, cardinals start talking about a new pope, there's hope for curing HIV, and (the royal) we are not well.
Kenya votes: Machete attacks mar opening of presidential election (LIVE BLOG)
The day was marked by early violence, high turnout, long lines and some technical problems.
Kenya's coast feels a sea away from national elections
In neglected coastal towns like Mombasa, many Kenyans may boycott Monday's vote.
On Location Video: Kenya's most unlikely candidate
He's young and from the slums. Can Elijah Kanyi do the unlikely and win a seat in parliament?
In Kenya, tribes vote with bloodshed before elections
Ahead of elections Monday, one part of Kenya has seen ethnic clashes escalate. The toll in Tana River is now more than 180, rights groups say.
Kenya election prompts fears of new violence
Kenyans vote for a new leader next week for the first time since the last election ended in more than a thousand deaths.
Kenya's chief justice 'threatened' over Kenyatta case
Kenya's Chief Justice Willy Mutunga said he and other judges have been threatened with "dire consequences" if courts bar presidential candidate Uhuru Kenyatta from running in the country's upcoming elections.
Assam rhino poaching: 9 rhinos killed so far this year
The Assam state government has requested permission from India's home ministry to arm forest guards with AK-series rifles to fight rhino poachers.
Kenya holds first-ever presidential debate
Millions tuned into Kenya's first-ever presidential debate on Monday.
Catholics everywhere have something to say
The world reacts to the pope's shocking announcement.
Glaring class disparity gains attention ahead of Kenya's presidential election
President Obama's focus on income inequality in America resonates with many in the land of his father.
Kenya: Barack Obama video message urges peaceful elections (VIDEO)
US President Barack Obama has released a YouTube video urging citizens of Kenya to support peaceful elections in March.
Iván Fernández Anaya's kindness reaffirms faith in athletes for some (VIDEO)
Spanish runner Iván Fernández Anaya helps confused Abel Mutai of Kenya win running race.
What the Oscars missed: That other foreign film
GlobalPost correspondents chime in with their overlooked picks for this year's Best Foreign Film.
Kenyan MPs award themselves lavish bonuses and benefits package
The bonuses alone are worth more than most Kenyans even dream about earning.
Elephant family slaughtered in Kenya
Poachers killed 11 elephants at a Kenyan National Park on Saturday for their ivory.
2,012 words of 2012
Here are the buzzwords, the keywords, or just plain words, that were uttered time and again in 2012. This was an absurd amount of work. So please click on it.
Kenya: Clashes in Tana River district kill over 30
Clashes between two ethnic groups in Kenya's Tana River district have killed over 30 and injured at least 30 more.
Chatter: Deadly fighting in Kenya as elections approach
Inter-ethnic fighting in Kenya kills almost 40 people, the US looks for a Plan C to save it from the fiscal cliff, and it seems we're all still here, after all.
Kenya: explosion rocks mostly Somali Nairobi enclave
Bomb strikes Kenyan capital.
Somalia's Al-Shabab offers $8K reward for killing Kenyan forces: officials
Radical Al-Shabab group reportedly offering big bounty for killing Kenyans.
Spanking, drunk driving and women's land rights
Commentary: An aid group explains how they persuaded Kenyan tribal to recognize equal rights for women.
Secret files show Kenya massacre cover-up
Secret documents just released show how British colonial authorities in Kenya tried to cover up the 1959 Hola detention camp massacre.
In Africa, lots of good news in the fight against AIDS
Major funding to fight AIDS in Africa, initiated by George W. Bush, continues to pay dividends.
Congo summit: African leaders gather to urge a halt to violence
A summit of leaders from Africa's Great Lakes region has urged M23 rebels in the Democratic Republic of Congo to stop the conflict.
Kenya grenade kills as many as 7
A grenade explosion on a Kenya minibus killed seven people and wounded another 24 on Sunday in a predominantly Somali neighborhood of Nairobi.
After massacre of police, army moves into northern Kenya
Residents of Kenya's rural north flee, worried about retaliatory attacks from Kenya's security forces.
Twins named after Obama and Romney in Kenya
Twins born in Kenya are named Barack and Mitt.
Obama wins: View from Kenya
It was 7 a.m. and the mud ground was littered with empty brandy bottles when CNN finally called it for Barack Obama.
As Kenyans eye US election, fears linger their own could turn bloody
A tribal power struggle led to more than 1,000 deaths around Kenya's last presidential election.
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PITTSBURGH -- The vote of confidence was much appreciated by Milwaukee Brewers manager Ken Macha. Even better was his bullpen's performance -- and the badly needed victory it produced.
George Kottaras, playing only because of an injury, doubled in the tying run and the Brewers rallied from a three-run deficit to end a nine-game losing streak that was their longest in nearly four seasons, beating the Pittsburgh Pirates 4-3 on Thursday night.
Hours after general manager Doug Melvin strongly supported Macha, the Brewers came back from 3-0 deficit in the first with two two-run innings despite having a thin bench and a beaten-up bullpen.
Carlos Villanueva finished it off by pitching the ninth for the first save this season by a Brewers reliever other than Trevor Hoffman, who sat out the two-game series to work on mechanical problems. Villanueva hit Ryan Doumit with a pitch before getting Delwyn Young to ground into a game-ending double play.
The Brewers were 5-for-13 in save opportunities -- Hoffman is 5-for-10 -- before Villanueva got his sixth career save. Milwaukee's bullpen came in with a 6.17 ERA, the NL's second-worst, only to pitch three scoreless innings in support of starter Chris Narveson (4-1).
Right-hander John Axford, making his third appearance since being called up from Triple-A, didn't allow a hit while pitching the seventh and eighth innings. He also pitched a scoreless inning as Pittsburgh won 6-4 on Wednesday, causing Macha to promise himself that he'd pitch him again Thursday.
Good move. Axford hit 96 mph on the radar gun with his fastball and threw several breaking balls that dropped a foot.
"That was just such a big lift out of the bullpen by Axford. You put an outing like that in, I'd say at least four of those nine games, we win the game," Macha said.
Neither home plate umpire John Hirschbeck nor Brewers catcher Gregg Zaun made it past the second inning.
Hirschbeck developed concussion-like symptoms when struck by a Narveson warm-up pitch that fooled Zaun as the Pirates were about to bat in the first. Hirschbeck stayed in the game as the Pirates took a 3-0 lead, only to be replaced by James Hoye before Milwaukee batted in the second. Three umpires finished the game.
"We were staring at the glare and talking about how bad it was and the next pitch, bam, right in the mask," Zaun said. "I felt so bad."
Zaun left with a strained right shoulder in the second. With outfielder Jody Gerut away to be with his pregnant wife, the Brewers were left with only two extra position players. Zaun will return to Milwaukee to be examined by doctors and is expected to go on the disabled list.
Milwaukee was so thin on the bench, pitcher Yovani Gallardo struck out pinch-hitting.
Zaun stayed in the game long enough to drive in a run with a grounder following Corey Hart's RBI triple in a two-run second inning. Kottaras then doubled to tie it and Adam Stern added a run-scoring grounder in the fourth as Milwaukee made good use of its four hits in seven innings off Paul Maholm (3-4).
"It was the best I felt all season, and it wasn't good enough," said Maholm, who struck out seven.
Maholm waited more than a half-hour to pitch between the first and second innings because of the Pirates' big inning and the Hirschbeck injury delay, and it admittedly got him out of his rhythm.
"Definitely, it's no excuse," he said. "It happens. But a couple of bad pitches, and there's the game."
In the Pirates' first, Steve Pearce drove a two-run triple over the head of center fielder Stern and Andy LaRoche followed with a double.
"You think that after you get a three-spot in the first ..." Pearce said. "We couldn't find a big hit."
Narveson was effective after that, giving up three hits over five shutout innings.
Game notes
Stern made his sixth career start in center field. The first five came with the Boston Red Sox in 2005-06. ... Prince Fielder went 0-for-3 against Maholm and is 3-for-40 (.075) against him in his career. ... Villanueva had three saves last season. ... Milwaukee avoided its first 10-game losing streak since late in the 2006 season.


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Many thanks, T2T. I'll see how your idea goes with Rory. He is so turned off maths now though that I hope that with your exciting idea he'll take a minute to 'play' with the idea! This math teacher by the way is his full-time teacher and also the head of training primary Montessori Teachers at Curtin University for the entire Australian Association of Montessori. You can faint now if you like! Kind regards and much thanks, Lee-Anne
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New items available in your FHANA portal
Jul 01 2016
FHANA would like to introduce many new features as part of your FHANA portal.
Notes from the Board of Directors
Jun 22 2016
1. The Board approved the proposal of the Sports Committe to create an Hours to Ride/Drive Program. This program will commence January 1, 2017. …
New Elements for Linear Score Form
Jun 08 2016
The linear score form reflects in great detail the degree of breed standard in a Friesian horse. In the upcoming inspection season two elements …
News Highlights
The Proper Care and Maintenance of Your (New) Saddle and Accessories
Jun 28 2016
Article written by By Jochen Schleese, CMS, CSFT, CSE as part of the Gold Sponsorship with Schleese Saddles.
FHANA Introduces Keuring Handbook
Jun 21 2016
Interested in attending a keuring and not sure what or where to start?
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Import and Sales of TOP quality, reasonably priced friesian horses. call janna 415-272-2112
Horseback riding lessons for beginners and all levels of riders. Lesson horses available or bring your horse. Youth and adults welcome, ride for…
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Showing - Sales - Training - Lessons - Clinics
horse training and horseback lessons.
I buy young horses, train them, and sell them once I feel that they are safe and that they have reached their full potential.


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The International Longshore and Warehouse Union will call delegates to San Francisco to consider a vote on early contract talks.
Pacific Maritime Association
The Pacific Maritime Association represents employers at ports and container terminals on the U.S. West Coast. It is responsible for negotiating labor contracts with the International Longshore and Warehous Union, which represents longshoremen at West Coast ports. The East Coast counterpart of the PMA is the United States Maritime Alliance, or USMX.
18 Apr 2016
Congressional representatives from western states and U.S. agricultural interests are urging the International Longshore and Warehouse Union and Pacific Maritime Association to launch early talks to extend their current contract beyond the Jul. 1, 2019, expiration date.
15 Apr 2016
LONG BEACH, California — Pacific Maritime Association President Jim McKenna on Friday formally requested that the International Longshore and Warehouse Union join employers in launching early talks to extend the existing West Coast labor contract beyond its July 1, 2019, expiration date.
01 Mar 2016
For the first time since the grueling contract negotiations of 2014-15, the presidents of the International Longshore and Warehouse Union and the Pacific Maritime Association said they are willing to raise with their memberships the possibility of extending the existing agreement beyond the July 1, 2019, expiration date in the interests of labor peace.


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Metrorail's rebuilding program will affect service on four lines this weekend. The Green Line will operate on its regular weekend timetable. All stations throughout the rail system will be open.
Because the trains are more widely spaced, riders should look up the exact schedules posted by Friday afternoon on Metro's Trip Planner. While this can shorten the wait on a platform, it's not foolproof. Metro trains are subject to the same delays on weekends that riders face on weekdays.
Here's a line by line look at the schedule changes for 10 p.m. Friday through midnight Sunday.
Red Line. Crews will work on the tracks between Farragut North and Van Ness stations. Trains are scheduled to leave the ends of the line at Shady Grove and Glenmont every 24 minutes throughout the weekend. From 9 a.m. to 9 p.m. Saturday and Sunday, extra trains will be in service between Farragut North and Silver Spring. In that zone, trains are scheduled to reach platforms every 12 minutes.
Orange Line. The platform reconstruction will continue at Minnesota Avenue and Deanwood. Trains are scheduled to operate every 24 minutes all along the line.
Blue Line. Crews will work on the tracks between Pentagon City and Arlington Cemetery. Trains are scheduled to operate every 24 minutes.
Yellow Line. Crews will work on the tracks between Pentagon City and L'Enfant Plaza. The trains are scheduled to operate every 24 minutes. They will end their northbound trips at Mount Vernon Square, rather than at Fort Totten. To continue past Mount Vernon Square, transfer to the Green Line.
Ask Metro
Metro General Manager Richard Sarles is scheduled to join me for my weekly online discussion at noon Monday. I plan to ask several questions, but most of the questions and comments will come from you. You can submit them now via this link, then use the same link to join the chat on Monday.


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IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards,
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An effective approach of simulating subsonic fluid dynamics on a cluster of non-dedicated workstations is presented. The approach is applied to simulate the flow of air in wind instruments. The use of local-interaction methods and coarse-grain decompositions lead to small communication requirements. The automatic migration of processes from busy hosts to free hosts enables the use of non-dedicated workstations. Simulations of 2D flow achieve 80% parallel efficiency (speedup/processors) using 20 HP-Apollo workstations. Detailed measurements of the parallel efficiency of 2D and 9D simulations are presented, and a theoretical model of efficiency is developed and compared against the measurements. Two numerical methods of fluid dynamics are tested: explicit finite differences, and the lattice Boltzmann method
A not-for-profit organization, IEEE is the world's largest technical professional organization dedicated to advancing technology for the benefit of humanity.© Copyright 2016 IEEE - All rights reserved. Use of this web site signifies your agreement to the terms and conditions.


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eLearning Lab with Ed2Go is your opportunity to take a choice of hundreds of courses offered through SFPL online! Ed2Go offers a wide range of highly interactive courses that you can take entirely over the Internet. All of the courses are led by expert instructors, many of whom are nationally known authors. The online courses are fun, fast, convenient, and best of all free with your San Francisco Public Library card. Each course runs for 6 weeks and our meeting room space will be available for two hours each week (Tuesdays from 1-3pm) to work on the course using our laptops. The courses available include art, technology, creative writing, business and management, and college preparation. You can find a full listing here http://www.ed2go.com/l-sfpl/
We do not provide headphones, so please bring your own. Space is limited! Please sign up in advance at the library or by calling 355-2810
Upcoming Events
- Coding Drop-In Lab
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Stolen check forged at Seneca bank
A check stolen from the mailbox of an Anderson County business turned up in Seneca where, the police say, the check was forged and cashed at a local bank. A 33-year old Anderson woman was arrested yesterday by the Seneca police and jailed in Walhalla. The police say Camie Ronea Dennis is accused of presenting a forged check in the […]Read more


text:
Pork Adobo
Total Time
Prep 15 mins
Cook 30 mins
The stew is slightly tart, but you can adjust exactly how tart by using more or less vinegar. I generally use more than soy, but my children like lots of "juice" so I add more soy to taste. Also, I tend to use jarred, minced garlic in place of fresh to save some time. The original recipe does not include onions or noodles and calls for boiling/simmering all the main ingredients until done and then straining the meat out so that you can brown it and thicken the sauce. Lungkow Vermicelli is bean thread noodles. I buy them at my local Asian store. 1 bundle is generally 1.3 ounces, but they come in packages of I think 8 bundles. They don't really have a taste on their own, but they soak up the flavor of the stew, and my kids love slurping them up.
Ingredients Nutrition
- 2 -3 lbs boneless pork, cut into bite-sized chunks
- 6 -10 garlic cloves, crushed
- 1 tablespoon black pepper
- 4 tablespoons soy sauce
- 1⁄2 cup white vinegar
- 3 cups water
- 1 large onion, chopped
- 1 -2 tablespoon cooking oil (to brown meat)
- 2 tablespoons cornstarch, mixed with equal amount cold water (optional)
- 1 1⁄3 ounces bean thread vermicelli (optional)
- 2 -4 cups cooked rice
- Brown pork in the oil.
- Place all the ingredients except cornstarch, vermicelli and rice into a pot and bring to a boil.
- Reduce heat and simmer for 30 minutes or until meat is tender.
- Now you have several options: a)To thicken the sauce with cornstarch just stir the mixture in and return to a boil for a minute, keep stirring to avoid clumps. b) If you're using the vermicelli, stir the noodles into the stew and cook for about 3 more minutes. The noodles are done when they're clear and soft. (You may need to add a little more water.).
Most Helpful
Never substitute jarred garlic with fresh. It might save "time" but the flavor is horrible, just horrible. Glad your kids like slurping the juices but this dish is best over rice.
This recipe was easy to make and tastes great! My family is very picky, and they couldn't get enough, so that says a lot! I liked the suggestion to use minced garlic instead of fresh, it was a real time saver!


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Created on July 21, 2016
The former Medina Theater has a date with the wrecking ball. But a documentary will help to preserve its history.
Created on July 7, 2016
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Testing teen driving skills
Created on June 17, 2016
The Medina High School boys basketball team held a cookout for the community surrounding Ray Mellert Park on North Huntington Street on June 16.
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Royalty and Rebels party raises money for charity.
Created on May 14, 2016
North Olmsted High School held its prom May 14 at LaCentre in Westlake.
Created on May 12, 2016
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Berea Community Garage Sale
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Aaron Costic of Elegant Ice Creations in Broadview Heights has won his eighth Ice Carving World Championship with his sculpture, "Concentration".
Created on March 10, 2016


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gas cleaning Companies in Nova Scotia
Current filtering criteriaYou can remove a filter by clicking on the x
California Analytical Instruments, Inc. (CAI)
based in Orange, CALIFORNIA (USA)
For more than 30 years, California Analytical Instruments, Inc. has produced the highest-quality gas analyzers and emission-monitoring systems for Industrial, Environmental, Process and Automotive applications. Bottom line: our instruments can accurately measure just about any gas. Our analyzers utilize proven technologies such as Chemiluminescence, Non-Dispersive ...
Pelrine & Buchanan's Maritime Trading Worldwide Ltd
based in Halifax, NOVA SCOTIA (CANADA)
Pelrine & Buchanan's Maritime Trading Worldwide Ltd. is located in beautiful Nova Scotia, Canada. We have been supplying used and surplus power generation equipment to customers worldwide for over 23 years. We offer diesel generator set, natural gas generators, gas turbines, coal fired power plants, steam turbines and cogeneration power plants. We offer equipment by world ...
Distributor in Halifax, NOVA SCOTIA (CANADA)
Sulzer is a global partner offering reliable and sustainable solutions for performance-critical applications. Our innovative solutions add value and strengthen the competitive position of our customers. Experience how Sulzer helps to cover the global demand for oil and gas. Pumps for up-, mid- and downstream applications, separation and process technologies for downstream ...
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You Are Here > CBB Home > Schools > Hiram Terriers > AP Poll History
News: See SportsLogos.net for historical and current sports logos »post
Also known as: Hiram College
Location: Hiram, Ohio ▪ Colors: Blue & Red
Record: 8 Years, 45-14, .763 W-L%
Conference: Ind
Conference Champion: 0 Times (Reg. Seas.), 0 Times (Tourn.)
No AP poll appearances for this school.
Current season data provided by SportsDirect Inc.


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As everyone knows, the only way to stop the slaughter in Syria is for the US to work with Assad – and to stop worrying about what looks good.
The reality is that the eurozone's managers care more about their loans and their beloved currency than they do about Greece.
Policing cities will always be tough, but that merely increases the need for clear political control.
The UK cosying up to Iran points to a creeping hypocrisy at play in Western military intervention.
The West's insensitive handling of issues in the Ukraine created Russian President Vladimir Putin's version of the Cuban missile crisis.
Defiant crowds may destroy an old regime, but seldom do they build a new one that endures.
There could be no more dreadful idea than to pour more armaments into the sectarian war that is consuming Syria.
While Rome burned, Nero put on fancy dress, stood on a tower and played his lyre, writes Simon Jenkins.
Cellphones may at last be falling victim to etiquette, but this is largely because even talk is considered too intimate a contact.
The Norwegian tragedy is just that, a tragedy. It does not signify anything and should not be forced to do so.
What would you do this morning if you were a Greek? Would you agree to your government cutting public-sector jobs, pay and pensions?