The present invention controls reagent flow levels in a selective non-catalytic reduction (SNCR) system by more accurately predicting Nitrogen Oxides (NOx) production with a municipal waste combustor. In one embodiment, the reagent levels correspond with measured furnace temperatures. The reagent levels may have a baseline level from prior measured NOx that is then modified according to temperatures measurements. A slow controller may use NOx measurements over an extended period to define a base regent level, and a fast controller may use additional information such as the furnace temperature to modify the base regent level. The fast controller may further receive two additional signals that are added individually or together to maximize NOx control while minimizing ammonia slip from the reagent. The two signals are a feed-forward signal from the combustion controller and a feedback signal from an ammonia analyzer downstream of the combustion zone.

The combustion of solid waste in a Municipal Waste Combustor (MWC) generates some amount of nitrogen oxides (NOx). NOx is the generic name for a group of colorless and odorless but highly reactive gases that contain varying amounts of NO and NO2. The amount of NOx generated by the MWCs varies somewhat according to the grate and furnace design but typically ranges between 250 and 350 ppm (dry value at 7% O2 in the flue gas).
The chemistry of NOx formation is directly tied to reactions between nitrogen and oxygen. To understand NOx formation in a MWC, a basic understanding of combustor design and operation is useful. Combustion air systems in MWCs typically include both primary (also called undergrate) air and secondary (also called overgrate or overfire) air. Primary air is supplied through plenums located under the firing grate and is forced through the grate to sequentially dry (evolve water), devolatilize (evolve volatile hydrocarbons), and burn out (oxidize nonvolatile hydrocarbons) the waste bed. The quantity of primary air is typically adjusted to minimize excess air during initial combustion of the waste while maximizing burnout of carbonaceous materials in the waste bed. Secondary air is injected through air ports located above the grate and is used to provide turbulent mixing and destruction of hydrocarbons evolved from the waste bed. Overall excess air levels for a typical MWC are approximately 60 to 100% (160-200% of stoichiometric (i.e., theoretical) air requirements), with primary air typically accounting for 50-70% of the total air.
In addition to destruction of organics, one of the objectives of this combustion approach is to minimize NOx formation. Nox is formed during combustion through two primary mechanisms: Fuel NOx from oxidation of organically bound elemental nitrogen (N) present in the municipal solid waste (MSW) stream and Thermal NOx from high temperature oxidation of atmospheric N2.
More specifically, fuel NOx is formed within the flame zone through reaction of organically bound N in MSW materials and O2. Key variables determining the rate of fuel NOx formation are the availability of O2 within the flame zone, the amount of fuel-bound N, and the chemical structure of the N-containing material. Fuel NOx reactions can occur at relatively low temperatures (<1,100° C. (<2,000° F.)). Depending on the availability of O2 in the flame, the N-containing compounds will react to form either N2 or NOx. When the availability of O2 is low, N2 is the predominant reaction product. If substantial O2 is available, an increased fraction of the fuel-bound N is converted to NOx.
In contrast, thermal NOx is formed in high-temperature flame zones through reactions between N2 and O2 radicals. The key variables determining the rate of thermal NOx formation are temperature, the availability of O2 and N2, and residence time. Because of the high activation energy required, thermal NOx formation does not become significant until flame temperatures reach 1,100° C. (2,000° F.).
However, NOx emissions are generally undesirable and are of environmental significance because of their role as a criteria pollutant, acid gas, and ozone precursor. Direct health concerns of NOx center on the gases' effects on the respiratory system because NOx reacts with moisture, ammonia and other compounds to form nitric acid and related particles that may damage lung tissue. These and other particles produced from NOx penetrate deeply into sensitive parts of the lungs and can cause or worsen potentially fatal respiratory diseases such as emphysema and bronchitis.
In addition, the emissions of NOx pose other environmental concerns. For example, ground-level ozone is formed when NOx and volatile organic compounds (VOCs) react with heat and sunlight. Children, asthmatics, and people who work or exercise outside are susceptible to adverse effects from the ozone, and these effects include lung tissue damage and decreased lung function. Ozone also damages vegetation and reduces crop yields.
Furthermore, the reaction of NOx and sulfur dioxide with other substances in the air to form acids, which fall to earth with rain, fog, snow or dry particles as acid rain. Acid rain damages or deteriorates cars, buildings and monuments, as well as causes lakes and streams to become unsuitable for fish.
In addition, NOx are indirect greenhouse gases that affect the atmospheric amounts of hydroxyl (OH) radicals. Specifically, the breakdown of NOx gases gives rise to increased OH abundance.
Consequently, various laws and regulations have been passed to limit the emissions of NOx from MWCs and other sources. For example, the Unites States Environmental Agency is authorized in 40 C.F.R. Part 60 to monitor and limit NOx from MWCs. Similar rules and regulations to limit NOx emissions likewise exist internationally, such as in Europe, Canada, and Japan. It should be appreciated that a complete understanding and knowledge of various rules and laws on NOx emissions are outside the scope of the current discussion.
NOx control technologies can be divided into two subgroups: combustion controls and post-combustion controls. Combustion controls limit the formation of NOx during the combustion process by reducing the availability of O2 within the flame and lowering combustion zone temperatures. These technologies include staged combustion, low excess air, and flue gas recirculation (FGR). Staged combustion and low excess air reduce the flow of undergrate air in order to reduce O2 availability in the combustion zone, which promotes chemical reduction of some of the NOx formed during primary combustion. In FGR, a portion of the combustor exhaust is returned to the combustion air supply to both lower combustion zone O2 and suppress flame temperatures by reducing the ratio of O2 to inerts (N2 and carbon dioxide (CO2)) in the combustion air system.
Post-combustion controls relate to removing NOx emissions produced during the combustion process at solid waste fired boilers, and the most commonly used post-combustion NOx controls include selective non-catalytic reduction (SNCR) systems, which typically reduce the NOx significantly, or selective catalytic reduction (SCR) systems, which typically reduce the NOx even more effectively than SNCR systems. As described in greater detail below, SCR systems are many times more expensive to build, operate, and maintain than SNCR systems and are consequently not economically feasible for use on waste-to-energy (WTE) plants in many parts of the world.
SCR is an add-on control technology that catalytically promotes the reaction between NH3 and NOx. SCR systems can use aqueous or anhydrous NH3 reagent, with the primary differences being the size of the NH3 vaporization system and the safety requirements. In the SCR system, a precise amount of a reagent is metered into the exhaust stream. The reagent decomposes into ammonia and reacts with NOx across a catalyst located downstream of the injection point. This reaction reduces NOx to elemental nitrogen and water vapor. SCR systems typically operate at temperature of approximately 500-700° F. In terms of waste disposal fee impact and cost effectiveness, SCR generally has higher costs resulting from high capital costs, as well as the cost of catalyst replacement and disposal.
In contrast, SNCR reduces NOx to N2 without the use of catalysts. Similar to the SCR system, the SNCR system injects one or more reducing agents (or "reagents") into the upper furnace of the MWC to react with NOx and form N2. Without the assistance of a catalyst, these reactions occur at temperatures of approximately 1600-1800° F. When the reagent is introduced in low amounts, virtually all of the reagent is consumed, and increasing the reagent amount in the SNCR systems may result in further NOx reductions. When operating the SNCR systems near the upper end of their performance range, however, excess reagent may be added to the reactor chamber, and the excess reagent passes through the MWC and ultimately escapes into the atmosphere, an undesirable phenomena known as ammonia slip.
SNCR systems are well known and disclosed, for example, by Lyon in U.S. Pat. No. 3,900,554 and by Arand et al in U.S. Pat. Nos. 4,208,386 and 4,325,924. Briefly, these patents disclose that ammonia (Lyon) and urea (Arand et al) can be injected into hot combustion gases within specific temperature windows to selectively react with NOx and reduce it to diatomic nitrogen and water. While described herein in connection with MWC systems, SNCR are also used to reduce NOx emissions from other combustion facilities, such as coal and oil furnaces and diesel engines.
The current SNCR controls typically use a slow-acting controller to adjust ammonia flow based on stack NOx emissions. In other words, the amount of ammonia introduced in a current time period generally depends on the average amount of NOx measured in the MWC emissions during one or more time periods. This approach works well with processes that have little variation in NOx emissions, such as coal or oil-fired boilers. Even when NOx emissions vary significantly on a minute-to-minute basis, this known approach works well to meet current regulatory limits because the regulatory limits are based on a long-term average NOx levels, such as a daily average, and are set at levels that are readily achievable with current control approaches. If tighter NOx limits or shorter averaging periods are required, however, this known approach using measured NOx emissions levels to control reagent levels results in potentially diminished NOx reduction and higher ammonia slip.
In particular, simply speeding up the response of the ammonia flow to the stack NOx signal is ineffective because of the time delay between NOx generation in the furnace and NOx measurement in the Continuous Emissions Monitoring (CEM) system that monitors stack emissions from the MWC. A control system that simply uses a faster response criteria will direct the SNCR system to respond to a temporary increase in NOx emission by increasing ammonia flow, even though the measured high NOx levels have already left the furnace area with the SNCR system. When the additional reagent is applied during subsequent periods of lower NOx levels, the increased ammonia flow may be excessive, causing increased ammonia slip. Likewise, the SNCR system responds to a temporary decrease in NOx stack emissions by decreasing reagent flow, and the decreased levels of reagent flow may be inadequate to optimally address relatively higher NOx furnace levels. In short, past NOx levels are a good indicator of current NOx levels for processes with little variation, or when controlling to readily achievable limits over relatively long time periods. When controlling to stricter limits in processes with highly variable NOx emissions, past NOx levels are no longer a good indication of current NOx levels.
Similarly, current reagent levels may depend upon other measurements. For example, in another known SNCR system control, the CEM system measures ammonia slip to determine the amount of un-reacted reagent contained in the stack emissions. The detected levels of current ammonia slip are then used to modify the amount of reagents applied in the SNCR system. However, ammonia slip levels, in themselves, may have little relevance to NOx levels, so adjusting the reagent level to minimize ammonia slip may provide relatively poor NOx reduction performance. In addition, the ammonia slip criteria of controlling SNCR system suffers from a similar deficiency to the NOx-based control systems in that the measured levels of current ammonia slip in the emissions, in itself, provides limited guidance about the reagent flow needed to address current future furnace conditions and resulting NOx levels in the furnace.

Dynamic control of selective non-catalytic reduction system for semi-batch-fed stoker-based municipal solid waste combustion


Embodiments of an RF amplifier include a transistor with a control terminal and first and second current carrying terminals, and a shunt circuit coupled between the first current carrying terminal and a ground reference node. The shunt circuit is an output pre-match impedance conditioning shunt circuit, which includes a first shunt inductance, a second shunt inductance, and a shunt capacitor coupled in series. The first shunt inductance comprises a plurality of bondwires coupled between the first current carrying terminal and the second shunt inductance, and the second shunt inductance comprises an integrated inductor coupled between the first shunt inductance and a first terminal of the shunt capacitor. The shunt capacitor is configured to provide capacitive harmonic control of an output of the transistor.

A typical high power, radio frequency (RF) semiconductor device may include one or more input leads, one or more output leads, one or more transistors, bondwires coupling the input lead(s) to the transistor(s), and bondwires coupling the transistor(s) to the output lead(s). The bondwires have significant inductive reactance at high frequencies, and such inductances are factored into the design of input and output impedance matching circuits for a device. In some cases, input and output impedance matching circuits may be contained within the same package that contains the device's transistor(s). More specifically, an in-package, input impedance matching circuit may be coupled between a device's input lead and a control terminal (e.g., the gate) of a transistor, and an in-package, output impedance matching circuit may be coupled between a current conducting terminal (e.g., the drain) of a transistor and a device's output lead.
Packaged RF semiconductor devices are available that have decent performance when used in relatively narrow-band applications with relatively low instantaneous signal bandwidth (ISBW) (e.g., ISBW of 150 megahertz (MHz) or less). However, increased ISBW (e.g., ISBW of 200 MHz or more) is becoming a major requirement for RF communication amplifiers (e.g., RF communication infrastructure amplifiers). This requirement stems from the fact that larger information download rates per second are becoming a significant enablement feature. Thus, trends in the RF communication industry include development of packaged RF semiconductor devices with increasingly wideband operation and relatively high ISBW.
Designing RF amplifier devices with high ISBW is challenging. For example, the ISBW of a device may be directly affected by the low frequency resonance (LFR) caused by interaction between the device's bias feeds and output circuits that are electrically connected between a device's transistor(s) and its output lead(s). More particularly, inductances of bondwires that interconnect various output circuit components may limit the LFR of the device.

RF power transistors with impedance matching circuits, and methods of manufacture thereof


In order to reduce the amount of time from when signals are sent to solenoid valves 19, 23, 24 for adjusting hydraulic pressures inside hydraulic pressure chambers of various hydraulic devices 7, 8, 14 assembled in a continuously variable transmission device until the hydraulic pressures are actually changed is shortened, the solenoid valves 19, 23, 24 adjust the hydraulic pressures inside hydraulic pressure chambers connected to hydraulic introduction paths where the solenoid valves 19, 23, 24 are provided by adjusting apertures of the solenoid valves 19, 23, 24 set according to duty cycles, and a controller 16 for the solenoid valves 19, 23, 24, when the apertures of solenoid valves 19, 23, 24 are changed beyond specified values to desired apertures, adjusts the apertures beyond the desired apertures to a state where the apertures have been changed a maximum amount, then after a specified amount of time, returns the apertures to the desired apertures.

Continuously variable transmission devices that include a toroidal continuously variable transmission are used as automatic transmission devices for vehicles, including automobiles. In this continuously variable transmission device, in order to increase the variable range of the transmission ratio, the toroidal continuously variable transmission may also be combined with a differential gear unit such as a planetary gear transmission. For example, JP 2011-174486 (A) and JP 2012-002330 (A) disclose a continuously variable transmission device that includes a mode in which the rotating state of the output shaft is switched between forward and reverse by passing through a so-called geared neutral state (GN) in which the rotating state of the output shaft is stopped while allowing the input shaft to continue to rotate as is in one direction.
FIG. 7 and FIG. 8 illustrate a conventional continuously variable transmission device that includes a mode that makes it possible to achieve a geared neutral state. FIG. 7 is a block diagram of a continuously variable transmission device and FIG. 8 illustrates a hydraulic circuit for controlling a continuously variable transmission. The output from the engine 1 is inputted to the main shaft 3 by way of a damper 2. The power that is transmitted to the main shaft 3 is then transmitted directly or by way of a toroidal continuously variable transmission device 4 to a planetary gear transmission 5 as a differential gear unit. The differential component of the component members of the planetary gear transmission 5 is output to the output shaft 9 by way of a clutch device 6 that includes a low-speed clutch 7 and a high-speed clutch 8 (see FIG. 8).
The toroidal continuously variable transmission 4 of the continuously variable transmission device includes an input disk 10, an output disk 11, plural power rollers 12, plural trunnions (not illustrated in the figure), an actuator 13 (see FIG. 8), a pressure device 14, and a transmission ratio control unit 15. The input disk 10 and output disk 11, as disclosed in detail in JP 2013-002330 (A), respectively include an axial side surface which is constituted of a toroidal curved surface, the axial side surfaces of the input disk 10 and output disk 11 facing each other, and the input disk 10 and output disk 11 are arranged so as to be concentric with each other and so as to be capable of relative rotation. Each of the power rollers 12 is supported by a corresponding trunnion so as to be able to rotate, is held between the axial side surfaces of the input disk 10 and output disk 11, and transmits power (force and torque) between the input disk 10 and output disk 11. The actuator 13 is a hydraulic actuator, and changes the transmission ratio between the input disk 10 and the output disk 11 by causing the trunnions that support the power rollers 12 to be displaced in the axial direction of pivot shafts that are provided on both end sections of the trunnions. The pressure device 14 is a hydraulic pressure device, and presses the input disk 10 and output disk 11 in opposite directions approaching each other. The transmission ratio control unit 15 controls the displacement direction and displacement amount of the actuator 13 in order to set the transmission ratio between the input disk 10 and output disk 11 to a desired value.
The transmission ratio control unit 15 includes a controller (ECU) 16; a stepping motor 17, a line pressure control solenoid valve 18, a pressure force control solenoid valve 19, and a mode switching solenoid valve 20, that are switched based on a control signal from the controller 16; and a control valve device 21 the operating state of which is switched by the stepping motor 17 and the mode switching solenoid valve 20. The control valve device 21 includes a transmission ratio control valve 22, a low-speed clutch control valve 23, and a high-speed clutch control valve 24 (see FIG. 8). The transmission ratio control valve 22 controls the supply or discharge of pressure oil to the actuator 13. The low-speed clutch control valve 23 and the high-speed clutch control valve 24 correspond to the mode switching solenoid valve 20, and switch the state of the hydraulic pressure to the low-speed clutch 7 and high-speed clutch 8.
An oil supply pump 25 is driven by power that is outputted from the damper 2, and pressure oil that is discharged from the oil supply pump 25 is fed to the control valve device 21 and the pressure device 14. In other words, pressure oil that is taken in from an oil reservoir 26 (see FIG. 8) and discharged from the oil-supply pump 25 is adjusted to a specified pressure by a pressure force adjustment valve 27 (see FIG. 8). The pressure force adjustment valve 27 adjusts the injection-valve opening pressure according to the hydraulic pressure which corresponds to the difference in hydraulic pressure (differential pressure) between a pair of hydraulic pressure chambers which are provided on both sides of a piston in the actuator 13, and introduction of hydraulic pressure based on the opening and closing of the line pressure control solenoid valve 18 that is controlled by an instruction from the controller 16. Then, taking this injection-valve opening pressure to be the maximum value, the pressure force control solenoid valve 19 regulates the pressure force generated by the pressure device 14 to an optimal value according to the operating state at that instant.
The hydraulic pressure that is adjusted by the line pressure control solenoid valve 18 and pressure force adjustment valve 27 is further adjusted (reduced) to a specified pressure by a reducing valve 28, and the hydraulic pressure is fed to inside the hydraulic pressure chamber of the low-speed clutch 7 or high-speed clutch 8 by way of the low-speed clutch control valve 23 or high-speed clutch control valve 24. The low-speed clutch 7 is connected in order to realize a low-speed mode in which the reduction ratio is increased, or the transmission ratio is made infinitely large (geared neutral state), and is disconnected in order to realize a high-speed mode in which the reduction ratio is decreased. On the other hand, the high-speed clutch 8 is disconnected in order to realize the low-speed mode, and is connected in order to realize the high-speed mode. The state of supplying or discharging pressure oil to the low-speed clutch 7 and high-speed clutch 8 is switched according to switching of the mode switching solenoid valve 20. When switching between the low-speed mode and high-speed mode based on switching between the low-speed clutch 7 and high-speed clutch 8, the transmission ratio of the toroidal continuously variable transmission 4 is adjusted so that the transmission ratio (1/reduction ratio) of the overall continuously variable transmission device is the same in the low-speed mode and the high-speed mode.
Signals respectively indicating the rotational speed of the input disk 10, output disk 1 and output shaft 9 which are detected by the input disk rotation sensor 29, output disk rotation sensor 30 and output shaft rotation sensor 31 are inputted to the controller 16. Moreover, the controller 16 then exchanges signals with the engine controller 32. Furthermore, a transmission mode switching signal that indicates the connected or disconnected state of the low-speed clutch 7 and high-speed clutch 8, and a T/M selection position signal that indicates the operating position of the selection lever are inputted to the controller 16. In addition, a paddle shift signal for a manual gear change, a foot brake signal that indicates whether or not the brake pedal has been operated, and an accelerator pedal aperture signal that indicates the amount that the accelerator pedal has been pressed are inputted to the controller 16 by way of the engine controller 32.
FIG. 9 illustrates an example of the relationship between the speed ratio of the toroidal continuously variable transmission 4 and the speed ratio of the overall continuously variable transmission device. For example, in the low-speed mode in which the low-speed clutch 7 is connected and the high-speed clutch 8 is disconnected, as illustrated by the solid line a, as the transmission ratio of the toroidal continuously variable transmission 4 is changed to the reduced-speed side from a value in which the geared neutral state is realized (GN value, GN point), the transmission ratio of the overall continuously variable transmission device is changed from a stopped state (state of a transmission ratio of 0) to a direction in which speed is increased in the forward direction (+:forward rotation direction). Moreover, as the transmission ratio of the toroidal continuously variable transmission 4 is changed to the increased-speed side from the GN value, the transmission ratio of the overall continuously variable transmission device is changed from a stopped state to a direction in which speed is increased in the reverse direction (−: reverse rotation direction). On the other hand, in the high-speed mode in which the high-speed clutch 8 is connected and the low-speed clutch 7 is disconnected, as illustrated by the solid line β, as the transmission ratio of the toroidal continuously variable transmission 4 is changed to the increased speed side, the transmission ratio of the overall continuously variable transmission device is changed to a direction in which the speed increases in the forward direction.
Switching between the low-speed mode and high-speed mode, or in other words, disconnecting and connecting the low-speed clutch 7 and high-speed clutch 8 is performed at the intersecting point γ of the solid lines α and β. At the point γ, the transmission ratio in the low-speed mode state and the transmission ratio in the high-speed mode state coincide with each other. As disclosed in JP 2005-191486 (A) and JP 2009-197892 (A), when switching between the low-speed mode and the high-speed mode, the clutch that was not connected up to that point is connected, and for an instant, the low-speed clutch 7 and high-speed clutch 8 are simultaneously connected. After that, only the newly connected clutch that corresponds to the mode to be realized next remains connected, and the clutch that was connected up to that point is disconnected. By providing an instant in which the low-speed clutch 7 and the high-speed clutch 8 are simultaneously connected in this way, a pick-up response of the engine when switching modes is prevented, and it is possible to reduce transmission shock.
With this kind of continuously variable transmission device, in order to smoothly switch between modes, the transmission ratios of these modes of the continuously variable transmission device coinciding during the instant of switching between the low-speed mode and high-speed mode is a precondition. When the low-speed clutch 7 and high-speed clutch 8 are simultaneously connected in a state in which these transmission ratios do not coincide, an excessively large load is applied to the toroidal continuously variable transmission 4. More specifically, at the areas of rolling contact (traction areas) between the input disk 10 and output disk 11 and the power rollers 12, the circumferential speeds of the pairs of surfaces that come in rolling contact do not coincide with each other. As a result, large slippage (cross slipping) occurs at the areas of rolling contact, and the durability of the toroidal continuously variable transmission 4 is severely impaired. Furthermore, there is a possibility that the toroidal continuously variable transmission 4 will break in a short period of time, and that operation of the vehicle in which the continuously variable transmission device is mounted will become impossible.
When the speed of a vehicle in which this continuously variable transmission device is mounted suddenly changes, or in other words, when the vehicle suddenly accelerates or decelerates, it is necessary to switch between the low-speed mode and high-speed mode in a short amount of time. For example, during the sudden acceleration process, the low-speed clutch 7 that was connected up to that point remains connected, and the high-speed clutch 8 that was disconnected up to that point is connected for a short amount of time, then after a state in which both the low-speed clutch 7 and high-speed clutch 8 have been connected for a short amount of time, the low-speed clutch 7 that was connected up to that point is disconnected. During a sudden deceleration process, the opposite state is realized. In either case, connecting both the low-speed clutch 7 and high-speed clutch 8 at the same time occurs only during a state in which the transmission ratio of the toroidal continuously variable transmission 4 is the same in the low-speed mode and high-speed mode, however, is essential from the aspect of protecting the toroidal continuously variable transmission 4. On the other hand, in order to switch between the low-speed mode and high-speed mode in a short amount of time, preferably disconnecting and connecting the low-speed clutch 7 and high-speed clutch 8 while continuously changing the transmission ratio of the continuously variable transmission 4 is performed in a very short time.
However, in the case of a hydraulic clutch, a certain amount of time is required after a signal indicating that the hydraulic pressure inside the hydraulic pressure chamber should be set to a desired pressure in order to disconnect or connect the clutch is generated until the hydraulic pressure inside the hydraulic pressure chamber actually reaches that desired value, which cannot be avoided. When the length of this time is so long that it cannot be ignored when compared with the amount of time required for disconnecting and connecting the low-speed clutch 7 and high-speed clutch 8, harmful slipping will occur in the areas of rolling contact in the toroidal continuously variable transmission 4 when switching between the low-speed mode and high-speed mode, which becomes the cause of impaired durability of the toroidal continuously variable transmission 4.
In the case of a continuously variable transmission that is constructed by combining a toroidal continuously variable transmission and differential gear unit such as a planetary gear transmission, and that switches between a low-speed mode and high-speed mode by disconnecting and connecting a hydraulic low-speed clutch and high-speed clutch, this kind of problem occurs even when construction is not capable of achieving geared neutral. A continuously variable transmission called a power split such as disclosed in JP H11-236955 (A) in which transmission efficiency is improved by transmitting power by only a toroidal continuously variable transmission in the low-speed mode, and transmitting power by both a toroidal continuously variable transmission and a planetary gear transmission in the high-speed mode is known. In this kind of power split continuously variable transmission as well, a similar problem occurs when switching modes.
In the case of either construction of a continuously variable transmission device, when the torque that is transmitted by the continuously variable transmission device changes suddenly, there is a possibility that adjustment of the pressure generated by the pressure device 14 will not be able to keep up. For example, during sudden acceleration when the accelerator pedal is suddenly pressed a large amount, it is necessary to increase the aperture of the pressure force control solenoid valve 19, increase the hydraulic pressure introduced inside the hydraulic pressure chamber of the pressure device 14, and increase the surface pressure at the areas of rolling contract of the toroidal continuously variable transmission 4. However, even when adjusting the hydraulic pressure that is introduced inside the hydraulic pressure chamber of the pressure device 14 by the pressure adjustment valve 27, it takes a certain amount of time until the hydraulic pressure inside the hydraulic pressure chamber of the pressure device 14 is adjusted to a desired value. When this rise in hydraulic pressure does not keep up with the rise in the output torque of the engine, harmful slipping occurs at the areas of rolling contact of the toroidal continuously variable transmission 4, which becomes a cause of impaired durability of the toroidal continuously variable transmission 4.
When the pressure force generated by the pressure device 14 is excessively higher than a value that corresponds to the output torque of the engine, the loss at the areas of rolling contact of the toroidal continuously variable transmission 4 increases, however, harmful slipping does not occur at the areas of rolling contact. Therefore, it becomes particularly important that adjustment of the hydraulic pressure inside the hydraulic pressure chamber of the pressure device 14 be performed so that the pressure is increased quickly. In order for this, JP 2009-121530 (A) discloses performing control of the pressure force generated by the pressure device based on the torque generated by the engine instead of the torque that passes through the toroidal continuously variable transmission when the accelerator pedal is suddenly pressed a large amount. In this case, it is possible to eliminate the insufficient pressure force during sudden acceleration to a certain extent, however, preventing insufficient pressure force by speeding up the timing at which a signal is sent to the pressure force adjustment valve is not able to shorten the time required for the hydraulic pressure inside the hydraulic pressure chamber to rise after the signal has been sent to the pressure force adjustment valve.


Thread-specific heaps are employed in multithreaded programs to decrease garbage collection latency in such programs. Program data in a target program is analyzed to identify thread-specific data and shared data. Thread-specific data is identified on the basis that the thread-specific data is determined to be reachable only from a single program thread of the target program. Each program thread can be associated with an individual thread-specific heap. Shared data is identified on the basis that the shared data is potentially reachable from a plurality of program threads of the target program. An exemplary method of identifying such data is referred to as a thread escape analysis. Garbage collection of such heaps may be performed independently or with minimal synchronization. Remembered sets may also be used to increase the independence of collection of individual heaps and to decrease garbage collection latency.

A computer program can use multiple categories of data storage during execution. Two such data storage categories involve a stack and a heap. The stack is typically an area of memory used for runtime data for methods, such as local variables, method return locations, intermediate results, etc. Alternatively, the heap includes an area of memory reserved for data that is created at runtime, wherein the lifetime of data in a heap typically is not determined by the lifetime of a particular method, whereas the lifetime of data in a stack is limited by the lifetime of the method with which the data is associated. In some approaches, however, a heap may also contain data normally put on the stack.
In addition, during execution, a program may no longer need data that has been allocated in the heap. Therefore, some method is required to reclaim the unneeded memory space from the heap. One method involves explicit program instructions to "free" the unneeded memory.
Another method is called "garbage collection." Garbage collection generally involves reclaiming the heap memory that is no longer being used by the program. Typically, in a multithreaded program, a heap is shared by multiple program threads. A program thread refers to a part of a program that runs somewhat independently of (e.g., non-sequentially with) other parts of the program. Program threads often share some of their environment with other program threads. For example, individual program threads may be distinguished by the value of their program counters and stack pointers. Program threads may also share a single address space and set of global variables.
However, garbage collection of a shared heap in a multithreaded program typically requires that access to the shared heap by other program threads (i.e., other than the garbage collection thread or threads) be suspended until the garbage collection is complete. Alternatively, all other program threads may be synchronized with one or more garbage collection threads to avoid corruption of the heap. Note: In some approaches, a program thread may perform its own garbage collection. Heap corruption can occur, for example, if a program thread allocates a program object to the shared heap during garbage collection by another thread (e.g., a garbage collector thread). For example, because the garbage collector thread lacks needed information about the new program object (e.g., which other program objects the new program object may reference), the garbage collector thread may inappropriately reclaim the memory associated with the new program object. As such, garbage collection in a multithreaded program traditionally requires synchronizing among the program threads or suspending the execution of the program threads during collection to prevent the program threads from arbitrarily modifying the shared heap during collection.
Both program thread-suspension and synchronization (e.g., forms of rendezvous) significantly contribute to garbage collection latency and impair performance of the program during garbage collection. Particularly for server-type applications with several hundred program threads, such garbage collection latency can present significant performance problems.


A method for determining transmission power for a user in a network. The method includes receiving a plurality of interference indicators by a user which is associated with a sector. The plurality of interference indicators corresponds to a plurality of sectors respectively each associated with one of a plurality of users and a base station. The method further includes processing at least information associated with the plurality of interference indicators and selecting an interference indicator based on at least information associated with the plurality of interference indicators. The selected interference indictor corresponds to one of the plurality of sectors. Additionally, the method includes determining a gain indicator corresponding to both the user and the one of the plurality of sectors, and processing information associated with the gain indicator. Moreover, the method includes determining a transmission power of the user based on at least information associated with the gain indicator and the selected interference indictor.

The present invention generally relates to telecommunication techniques. More particularly, the present invention relates to a method for providing a scheme for network users to manage their transmission powers and inter-sector interferences in uplink wireless communications. More specifically, embodiments of the present invention allows optimal allocation of uplink transmission power for each user with fair management of inter-sector interference in an Orthogonal Frequency Division Multiple Access (OFDMA) network. But it would be recognized that the invention has a much broader range of applicability.
The next generation of wireless networks will use OFDMA (Orthogonal Frequency Division Multiple Access) technology for a user attached with an access terminal (AT) in the uplink network communication. In OFDMA, the uplink resources assigned to a user are called tiles each of which consists of a subset of consecutive subcarriers. Since at most one user is assigned to each of these tiles then uplink transmissions within a sector are orthogonal or have no interference. However, the user AT transmission is still affected by inter-sector interference since other users in adjacent sectors may also have been assigned to the same tile. If those users in the adjacent sectors transmitted with high power then the inter-sector interference may severely limit the signal to interference and noise ratio (SINR) achieved by the user. Therefore, user transmission powers must be carefully managed to avoid excessive inter-sector interference.
For example, FIG. 1 illustrates a conventional method for dealing with transmission power adjustment for multiple users to achieve higher rates in the uplink of an OFDMA network. As shown, considering one of the users, and the user corresponds to a sector:
The transmission power of the user is increased for achieving a higher rate;
The interference caused by the user on adjacent sectors increases;
Users in adjacent sectors increase their powers to counter the increased interference and maintain their original rates;
The increased power of users in the adjacent sectors results in an increase in the interference in the sector;
The user must increase power to counter this increased interference; and
The sequence of events repeats until the user reaches its maximum transmission power.
Such an approach leads to a result that all users transmit with maximum power which is not an optimal use of uplink resources. Instead, system stability is better maintained by controlling user uplink transmission powers so as to maintain the interference at each sector within an acceptable range. In other words, in the uplink of an OFDMA network, the user AT transmission power must be chosen large enough to provide the desired rate for the user, but not too high to significantly degrade transmissions in neighboring sectors because of the interference caused to those transmissions.
In general, simply maintaining interference level within a set limit will not result in an optimal or fair solution. For example, consider a simple case of two sectors with two users. Even if only one user is transmitting, its rate is limited because of the limit placed on the interference it causes on the second sector. Clearly this is not optimal. Furthermore, suppose adding a third sector and that a user in that sector wishes to transmit. Then the user in the first sector is transmitting with sufficient power to cause the interference limit on the second sector to be reached. The third user then cannot transmit because doing so will cause the interference constraint for the second sector to be violated. This demonstrates that the system may not be fair. If the user in the third sector had instead started transmitting before the user in the first sector then the user in the first sector would similarly not be able to transmit. Hence the solution is non-unique and this may potentially result in instability.
Within a framework of the Third Generation Partnership Project 2 (3GP2), the inter-sector interference information is broadcast by sectors and can be used by ATs to adjust powers. Certain conventional techniques based on the framework for dealing the above problem are often not adequate for various reasons. For example, some central entity may require to collect all information associated with the AT transmissions and interferences, then compute the solution and inform each sector of this solution, or each sector must combine this information then determine an optimal solution. These conventional solutions require the exchange of a large amount of information and the delay in collecting this information may mean that the computed solution is no longer optimal when applied.
Therefore, an improved technique based on a distributed algorithm for providing optimal allocation of uplink transmission power is desired.

Method and system for optimal allocation of uplink transmission power in communication networks


A device for separating at least part of the liquid component of a blood sample and methods thereof are disclosed. Generally, the device includes a container body for receiving the blood sample, a layer of retaining porous material, a layer of separating permeable material. The retaining porous material retains non-liquid components of the blood sample after the non-liquid components have been subjected to centrifugal force which forces them through the separating permeable material into the retaining porous material.

The separation of liquid components of blood samples, e.g. plasma and serum, is a necessary and important pre-analytical step in clinical diagnostics.
Known methods for performing the above mentioned separation require a considerable amount of manual work and time. The automation of that manual work, both in terms of throughput, workflow and reliability, becomes essential.
An important parameter is the time required for plasma or serum separation during centrifugation. This time could be substantially reduced by centrifugation of the sample tube around its axis of symmetry instead of using the conventional swing bucket method. This is because the length of the motion path followed by cell components of blood sample during centrifugation of the sample container about its symmetry axis is much shorter than in a conventional swing bucket centrifugation of a primary sample tube. When swing bucket centrifugation of a sample tube containing a blood sample is performed the rotation axis is perpendicular to the length axis of the sample tube and the motion path followed by cell components of blood sample during the centrifugation is much longer because the cell components move along the length axis of the sample tube towards the bottom of this tube.
If a primary sample tube is used for example as a sample container for centrifugation around its axis of symmetry, the length of the motion path followed by cell components of blood sample during centrifugation is less than the length of the radius of the primary sample tube, e.g. between 1 and 4 mm.
A problem associated with primary sample tube centrifugation around its axis of symmetry is the maintenance of the separation after centrifugation is stopped. The separated non liquid components are only temporary stuck against the internal wall of the sample tube and will mix again with the liquid component to then slowly sediment at the bottom of the tube.
In U.S. Pat. No. 4,509,941 a sample tube is disclosed comprising a porous material for entrapping blood cells when the tube is centrifuged along its vertical axis. A particularly designed cap helps to keep the porous material in place against the interior wall of the tube. A problem however remains, as the blood cells are not steadily trapped in the porous material. The same document discloses that plasma itself can be used to release the red blood cells from said material. This means that if the separated plasma is not removed quickly, it will be contaminated again by the blood cells.

Device and method for separating a liquid component of a blood sample, and analyzer apparatus comprising such a device


In accordance with the teachings of the present invention, wavelength selective switch (WSS) design configurations for mesh light-trails are provided. In a particular embodiment, a node included in an optical network comprises a first light access unit operable to add or drop local traffic and a first WSS assembly communicatively coupled to the first light access unit and comprising at least four WSSs, at least two input ports, and at least four output ports, the four WSSs configured to direct any input traffic in any wavelength received at one of the input ports to the first light access unit and/or to any of the output ports.

Telecommunication systems, cable television systems, and data communication networks use optical networks to rapidly convey large amounts of information between remote points. In an optical network, information is conveyed in the form of optical signals through optical fibers. Optical fibers comprise thin strands of glass capable of transmitting optical signals over long distances with very low loss of signal strength.
In recent years, the use of telecommunication services has increased dramatically. As the demand for telecommunication services continues to grow, optical networks are quickly becoming overburdened by the increasing amount of information communicated over such networks. The addition of new networks or the expansion of existing networks may however be too costly to be practical solutions to this problem. Thus, efficient use of network resources has become an important goal in developing and operating optical networks.
Optical networks often employ wavelength division multiplexing (WDM) or dense wavelength division multiplexing (DWDM) to increase transmission capacity. In WDM and DWDM networks, a number of optical channels are carried in each fiber at disparate wavelengths. Network capacity is based on the number of wavelengths, or channels, in each fiber and the bandwidth of the channels. By using WDM add/drop equipment at network nodes, the entire composite signal can be fully demultiplexed into its constituent channels and switched (added/dropped or passed through).
In WDM and DWDM networks, traffic from one network node to another network node is often assigned to a particular wavelength on which the traffic is communicated over the network. By assigning different traffic streams to different wavelengths, interference between different traffic streams is prevented. However, in certain situations, this creates inefficiency in the network. For example, if the traffic from a node that is assigned a particular wavelength does not typically use much of the bandwidth (capacity) associated with the wavelength, then inefficiencies are created.
The use of optical light trails has been proposed to address these inefficiencies. A light-trail is a generalization of a light path (an optical wavelength circuit), where multiple nodes along the path can take part in communication along the path. Thus, a light-trail enables a plurality of nodes included in the light-trail to share the use of an optical wavelength to transmit traffic between the nodes included in the light-trail. Besides addressing some of the inefficiencies discussed above, light-trail communications may also allow optical multicasting and dynamic provisioning.
Although light-trails have been proposed as efficient solutions to some optical networking inefficiencies, a need remains for efficient and reliable optical component configurations to implement light-trails in particular optical networks.

Wavelength selective switch design configurations for mesh light-trails


A system for providing high resolution imaging of objects having sub-millimeter dimensions comprised of at least one transmitter, at least one receiver, a coupling chamber, and a processor for recording attenuation and time of flight profiles of the transmitted signals. The signals are conditioned in a manner to provide high signal-to-noise ration (SNR) and minimal crosstalk and multipath effects at the receiver.

1. Field of the Invention
This invention relates to imaging a three dimensional object using high resolution scanning in tomographical applications.
Specifically, the present invention relates to signal processing systems and methods for creating a high-resolution image of an object using ultrasonic tomography.
2. General Background
Ultrasonic transmission tomography has been used in the past for two dimensional imaging of an object of interest. The signals used for transmission were either pulse or sinusoidal waveforms.
There are often several limitations in this prior art, such as: (i) the resolution of the image of the object is limited, (ii) the time for scanning an object of interest may be quite long, and (iii) there are errors due to cross talk or multipath effects when multiple transmitter elements are used for simultaneously transmitting signals.
Also, the systems used in 3D imaging involve reflection mode (pulse echo) as a means for communicating a signal between a transmitter and a receiver. As is well known, in pulse-echo mode of communication, the receiver element operates on a signal bounced off an object. No comparable imaging systems are known for transmission mode where the receiver element can operate on a signal attenuated and diffracted about an object.

High-resolution 3D ultrasonic transmission imaging

Alfred E. Mann Institute for Biomedical Engineering at the University of Southern California


A core voltage discharger is capable of adjusting an amount of a current discharged according to temperature. The discharger for decreasing a level of a predetermined voltage receives temperature information from an on die thermal sensor and discharges a different amount of current in response to the temperature information.

The present invention relates to a discharger for discharging a predetermined voltage or a core voltage (VCORE) and a semiconductor memory device including the same, and more particularly to a discharger capable of discharging a different amount of current according to temperature and a semiconductor memory device including the same.
As is well known, a dynamic random access memory (DRAM) amplifies a signal using a bit line sense amplifier in a data read operation, and uses an overdriving scheme in an initial enabling period of the bit line sense amplifier in order to improve a sensing speed.
FIG. 1 is a signal timing diagram illustrating an overdriving scheme in a conventional bit line sensing operation. An amplification process and an overdriving operation of a bit line sense amplifier will be described below with reference to FIG. 1. In general, when a bitline isolation signal BIS is activated, the cell array and the bitline sense amplifier are electrically coupled to each other. When the bitline isolation signal BIS is deactivated, the cell array and the bitline sense amplifier are electrically decoupled form each other. Moreover, when a bitline equalization signal BLEQ is activated, the bitline pair BL and /BL is precharged to the precharge voltage VBLP.
A charge sharing occurs between a cell and a precharged bit line when a word line WL of the selected memory cell is enabled. Therefore, a slight voltage difference (dV) occurs between a bit line BL and a bit line bar BLB. This period is represented by a reference numeral "102" in FIG. 1.
Thereafter, a bit line sense amplifier is enabled. The voltage difference is widened, so that the bit line BL and the bit line bar BLB are set to the levels of a core voltage VCORE and a ground voltage VSS, respectively. The bit line sense amplifier is enabled by applying voltages to driving its voltage lines RTO and SB. More specifically, the bit line sense amplifier is enabled by applying the core voltage VCORE and the ground voltage VSS to the driving voltage lines RTO and SB, and amplifies voltages applied to the bit lines BL and BLB.
As described above, the bit line sense amplifier is overdriven by applying a high voltage (generally, a power supply voltage VDD) higher than a core voltage VCORE to the driving voltage line RTO during an initial enabling period. This overdriving period is represented by a reference numeral "103" in FIG. 1. A width of the overdriving period is determined by a pulse width of an overdriving pulse.
FIG. 2 is a circuit diagram of a conventional memory core.
Referring to FIG. 2, a conventional memory core includes a bit line sense amplifier 210, a sense amplifier driver 220, and a core voltage discharger 230.
The bit line sense amplifier 210 amplifies a voltage difference between a bit line BL and a bit line bar BLB. The bit line sense amplifier 210 is a latch type amplifier having two inverters cross-coupled to each other. A power supply voltage is applied to the bit line sense amplifier 210 through driving voltage lines RTO and SB.
The sense amplifier driver 220 includes transistors T1 and T2 that are respectively turned on when control signals SAP and SAN are activated. The sense amplifier driver 220 applies a core voltage VCORE or a power supply voltage VDD to a driving voltage line RTO, and a ground voltage VSS to a driving voltage line SB. In an initial enabling period, a transistor T3 is turned on in response to an overdriving pulse VDD_ON to supply a power supply voltage VDD to the driving voltage line RTO. The period where the high voltage VDD is supplied to the driving voltage line RTO is determined by a pulse width of the overdriving pulse VDD_ON. When the initial overdriving operation is finished, the transistor T3 is turned off and a transistor 14 is turned on. Thus, a core voltage VCORE is supplied to the driving voltage line RTO so that the bit line sense amplifier 210 is driven.
When the overdriving operation is finished and the core voltage VCORE begins to be supplied to the driving voltage line RTO, a current flows into a core voltage terminal from the driving voltage line RTO by the power supply voltage VDD previously applied to the driving voltage line RTO, thereby increasing a level of the core voltage VCORE. Therefore, a core voltage discharger 230 is required which can drop the increased level of the core voltage VCORE to the original level.
FIG. 3 is a graph illustrating the core voltage VCORE increased by the overdriving operation.
In FIG. 3, ΔV1 represents an increment of the core voltage VCORE, which is increased by a current flowing into the core voltage terminal by the power supply voltage previously applied to the driving voltage line RTO. In the absence of the core voltage discharger 230, the increased core voltage VCORE is slightly discharged by a leakage current or a small transistor, which is intentionally provided in the core voltage driver so as to stabilize the level of the core voltage VCORE. Accordingly, it is difficult to maintain the level of the core voltage VCORE to a target level TARGET CORE thereby not reaching an actual level ACTUAL CORE of the core voltage VCORE. In FIG. 3, ΔV2 represents an amount of a voltage discharged by the leakage current or the small transistor. That is, in the absence of the core voltage discharger 230, the level of the core voltage VCORE is not stably maintained. Instead, the level of the core voltage VCORE increases.
FIG. 4 is a schematic circuit diagram of a conventional core voltage discharger.
Referring to FIG. 4, the conventional core voltage discharger 230 discharges a core voltage VCORE by comparing the core voltage VCORE with a reference voltage VREFC. A level of the reference voltage VREFC may be set to a level substantially equal to the core voltage VCORE or half the core voltage VCORE. FIG. 4 illustrates the case where the level of the reference voltage VREFC is half the core voltage VCORE.
A discharge enable signal DC_EN has a logic high level in synchronization with a falling edge of an overdriving pulse VDD_ON indicating an overdriving period. The core voltage discharger 230 operates during the period in which the discharge enable signal DC_EN is at the logic high level.
When the discharge enable signal DC_EN becomes the logic high level, a transistor N3 is turned on to enable the core voltage discharger 230 to perform the comparison operation. The core voltage discharger 230 compares a voltage level of a half core voltage node HFVCORE with a voltage level of a reference voltage node VREFC, which corresponds to half the target voltage of the core voltage VCORE.
The node HFVCORE has a voltage level higher than the reference voltage VREFC when the core voltage VCORE is increased by the overdriving operation. Therefore, a transistor N2 is turned on stronger than a transistor N1, and a node B has a voltage level lower than a node A. A transistor P4 is strongly turned on and a voltage of a node DC_CTRL increases. A discharge transistor N5 is turned on by the increased voltage level of the node DC_CTRL, and the voltage level of the core voltage VCORE is dropped by a current flowing from a core voltage terminal to a ground voltage terminal due to the transistor N5.
That is, when the current core voltage VCORE is higher than the target core voltage VCORE, the core voltage discharger 230 drops the level of the core voltage VCORE by discharging a current from the core voltage terminal.
A level variation of the core voltage VCORE by the discharge operation of the conventional core voltage discharger 230 will be described with reference to FIGS. 5A and 5B. Transistors P1 and P2, transistors P3 and P4 and transistors N8 and N9 are respectively formed current mirror. The transistors N6 and N7 are formed an active load. When the discharge enable signal DC_EN becomes Low, the transistors N4 is turned on to supply a ground voltage VSS to the node DC_CTRL.
FIG. 5A is a graph illustrating the level variation of the core voltage VCORE when the core voltage VCORE is excessively discharged by variation of process, voltage, and temperature (PVT). Referring to FIG. 5A, the level of the core voltage VCORE is excessively dropped due to the excessive discharge of the core voltage VCORE in an initial stage, and thus a core voltage driver again operates to increase the level of the core voltage VCORE. Therefore, a ringing phenomenon is generated to fluctuate the level of the core voltage VCORE.
FIG. 5B is a graph illustrating the level variation of the core voltage VCORE when the core voltage VCORE is not sufficiently discharged by the variation of the PVT. A target level of the core voltage VCORE is not achieved until a discharge operation of the core voltage discharger 230 is finished. In this situation, the level of the core voltage gradually increases by repeating an overdriving operation.
The core voltage may be excessively or insufficiently discharged by the temperature variation, thereby causing the problems as illustrated in FIGS. 5A and 5B. However, since the conventional core voltage discharger 230 has no temperature dependence, the core voltage is excessively or insufficiently discharged by the temperature variation.

Core voltage discharger and semiconductor memory device with the same


An electro-mechanical variable fluid flow restrictor includes a support having a passage and a seal surface, a deformable seal that is engageable with the seal surface, and a bias member for exerting an electronically controlled variable bias against the deformable seal. The seal surface includes channels formed in its surface that extend beneath the deformable seal. The bias member can exert a bias sufficient to cause the deformable seal to fill the channels, preventing fluid flow through the channels. When the bias member decreases the bias against the deformable seal, the deformable seal gradually moves out of the channels, allowing fluid flow through the channels, and through the passage in a flow control. The deformable seal does not need to separate from the seal surface to allow fluid flow. Instead, fluid flows through the small, controlled flow areas created when the deformable seal withdraws from the channels.

Many applications, such as gas chromatography applications, require a controlled source of pressure and/or flow of a fluid in order to obtain accurate and repeatable measurements. Pressure regulators are commonly used to maintain the pressure of a fluid in a test device at a constant target pressure to ensure accurate and reproducible measurements. Flow controllers, also referred to as mass flow controllers, are used to control the flow of a fluid, such as a gas or a liquid, through a test device, such as a gas chromatograph.
A typical pressure regulator includes a chamber having a regulated pressure. The regulated chamber is in fluid communication with the test device so that the pressure in the test device is regulated along with the pressure in the chamber. The pressure regulator also includes a source of pressurized gas and a valve for releasing the pressurized gas into the chamber. The source of pressurized gas is used to raise the pressure in the chamber when the pressure falls below the target pressure. A mass flow controller uses a similar valve to control and regulate the flow through the valve using, for example, a flow measurement as feedback to control the flow through the valve.
Some valves have a cylindrical seal and some valves have an o-ring seal that controls the flow of gas from the source to the chamber. Such valves can also be referred to as a variable fluid flow restrictor. The seal is normally biased against a valve seat when the chamber is above the target pressure. When the pressure in the chamber falls below the target pressure, the bias against the seal is released, and the seal separates from the valve seat, allowing the pressurized gas to flow into the chamber.
A disadvantage to these types of valves is that when the seal separates from the valve seat, it does not maintain a stable position. Instead, sections of the seal may actually oscillate between separation and contact with the valve seat. The material of the valve seal may also stick to the surface of the valve seat, a condition referred to as "stiction." Stiction between the valve seal and the surface of the valve seat may cause a hysteresis effect when the valve attempts to open, sticks, and then opens further than desired. Once the valve opens further than desired, the valve may exceed its setpoint and then immediately close to compensate, thus producing an undesirable hysteresis effect. Such hystersis makes the valve difficult to control. Regardless of the manner caused, oscillation of the seal creates disturbances in the flow of pressurized gas, which causes unstable gas flow through the valve and pressure anomalies in the chamber receiving the pressurized gas. Because the test device is in fluid communication with the chamber, the pressure within the test device fluctuates, which negatively affects measurements taken in the test device.
Accordingly, a need exists for a flow control capable of providing stable fluid flow.

Flow control providing stable fluid flow


The prior art packaging of microelectric wires that have had insulation stripped from at least one end to permit the wires to be used in an electric circuit has applied adhesive to the backs of the paddleboards to which the microelectric wires are connected for testing. The adhesive is objectionable because residues of adhesive remain on the paddleboards and interferes with subsequent operations. The package of this invention eliminates adhesive on the paddleboards by forming the bottom layer of the paddleboards with frangible ligaments that are connected to a transversely extending spine. A base supports the paddleboards and spine, and it is the spine, not the paddleboards, that is connected to the underlying base. Each paddleboard can be removed from the spine and from the package by breaking the frangible ligament connecting that paddleboard to the spine. In one embodiment of the invention, each paddleboard is mounted in a recessed tray wherein a group of projections rise within the recessed body of the tray to the top of the tray. The spine has a corresponding group of openings therethrough which register with the projections in a first tray when a group of paddleboards is assembled within said first tray. The projections within said first tray penetrate the openings in the spine of the paddleboards within said first tray and extend into engagement with a second tray on top of said first tray.

One segment of the computer industry prepares microelectric wires, or microwires, having a predetermined length of, for example, three inches and a diameter in the range of 0.001 to 0.002 inches, for installation by another segment of the computer industry in the hard drive systems of computers.
Each of the microwires is insulated by a thin enamel coating. A specific length of insulation is stripped from at least one end of each microwire before twisting two or more of the microwires together to form a microwire electrical conductor with two or more strands (herein called microelectric wires).
The microelectric wires are cut to precise predetermined lengths and corresponding ends of the wires are attached to a printed circuit board or test board (generally known in the industry as a paddleboard) before being packaged for shipment to a member of that segment of the computer industry that installs the microelectric wires in the hard drive systems of computers, or other desired environment.
The paddleboards are miniature printed circuit boards of three ply construction. An upper layer comprises two or more spaced strips of tin/lead solder laminated to an intermediate layer defined by a like number of strips of a copper substrate which is, in turn, laminated to a non-conductive base or bottom layer, preferably formed from epoxy resin-bonded cellulosic board. The strips of tin/lead solder are soldered to corresponding ends of the strands of a microelectric wire to form an electric connection.
The paddleboards, with a microelectric wire attached to each board, have heretofore been packaged for shipment by first arranging a plurality of the paddleboards (twenty, for example) in a row with the paddleboards in juxtaposition to each other and holding the paddleboards in place with a strip of adhesive tape attached to the backs of the juxtaposed paddleboards. The adhesive tape is fastened, as by staples, to a suitable base, such as a stiff sheet of paperboard measuring approximately four by six inches. A second sheet of correspondingly sized paperboard is used to cover the paddleboard and protect the microelectric wires. The two juxtaposed sheets of paperboard are held together, with the paddleboard and wires sandwiched between them, as by rubber bands, to complete the prior art package.
It is known to practitioners of the art that a residue of adhesive from the adhesive tape used in the prior art package undesirably remains on the backs of the paddleboards when they are removed from the package. This residue of adhesive is objectionable because it often causes the paddleboard to become accidentally stuck to something, disrupting the normal flow of work with a consequent loss of production.
When a paddleboard is placed in the test block for testing of the electric circuit, a portion of the adhesive residue on the back of the paddleboard is transferred to the test block. After a plurality of paddleboards have been tested in the test block, there is an undesirable accumulation of adhesive in the test block, which interferes with its satisfactory use.

Package for microelectric wire test boards


Propellers of a marine transport vessel may be independently controlled at their optimal speed when at least one transmission having a plurality of output shafts capable of independent-speed ratios is connected to an engine and the propellers are respectively mounted at the output shafts of the transmission.

(a) Field of the Invention
The present invention relates to a power train of a marine transport vessel, and more particularly, to a power train that can control a plurality of propellers with various speeds even if only one engine is adopted.
(b) Description of the Related Art
As is well known in the art, various kinds of marine transport vessels are used for transportation of passengers or cargo on water such as lakes, rivers, and oceans.
Such a marine transport vessel includes an engine for generating power and a transmission for transmitting the generated power to propellers. Usually, such an engine and a transmission are collectively called a power train. Hereinafter, the term "propeller" is used to include not only a conventional propeller for generating water current but also any rotating device for generating a reactive force to a body of the marine transport vessel. The term "marine transport vessel" is used to mean any marine vessel that moves by the reactive force of the propeller. In more detail, the marine transport vessel does not necessarily move on the water, but it may rather move under the water.
The transmission may be realized in a variety of forms, such as an automatic transmission or a manual transmission. However, a semi-automatic transmission described in Korean Patent No. 292325 (of which the filing no. is 10-1998-0063295) is very effective.
According to a conventional power train of such a transport vessel, an engine such as an internal combustion engine outputs power (i.e., torque) through one output shaft and a transmission that receives the output torque changes the rotational speed and then transmits it to a propeller. During such a power transmission, only one speed-ratio is realized.
According to such a conventional scheme of a power train, a power transmission pattern is very limited since the torque output from an engine having only one output shaft is changed by only one speed-ratio and is then transmitted to the propellers. That is, one engine can operate one or more propellers only at the same speed.
As a result, the behavior of a marine transport vessel is also limited. For example, for changing the direction of the vessel, rudders to the rear of the propellers are operated such that a direction of a reactive force is changed and thereby a torque for turning the direction of the vessel is generated. The turning radius of the vessel is consequently very large, as is well known in the art.
When such a turning radius of a vessel is reduced, various merits can be accordingly achieved. For example, the vessel may turn in a narrow region and accordingly interference between vessels may be minimized.
In order to provide different torques to different propellers, the vessel may adopt a plurality of engines and a plurality of transmissions respectively connected to the engines. However, in this case, torques of the separate engines are not easy to harmonize, and a large space is inevitably consumed by the engines and the transmissions.

Power train of a marine transport vessel


A pivoting tip assembly for a walking cane, which accommodates both tilting and rotation of the shaft of the cane while the base of the tip remains in stationary engagement with the floor. A disk member is mounted to the lower end of the shaft for rotation about the long axis thereof, and has a rounded outer edge which engages the inner surface of a socket formed in the rubber tip. The disk member is sized to have a sliding fit with the inside surface of the socket, so that the disk is able to tilt within the socket as the shaft of the cane tilts back and forth. The opening at the top of the socket is sized larger than the shaft, so that the shaft can tilt through a predetermined range of angular movement before striking the lip of the cup; at the limit of travel, the shaft comes into contact with the resilient material of the cup, which provides a yielding stop to the tilting motion. A radial skirt is mounted to the shaft above the tip assembly, which permits the operator to retrieve the cane without having to bend over, by stepping on the tip of the cane and then sliding a foot under the upper end of the shaft so as to pivot the cane to a position in which the handle is within reach.

a. Field of the Invention
The present invention relates generally to walking canes, and more particularly, to a walking cane having a tip assembly which is able to tilt and rotate relative to the shaft during use so as to reduce the possibility of a slip or fall.
b. Background Art
Most walking canes are provided with a rubber tip in an effort to provide stable engagement between the cane and a floor or other underlying support surface. In practice, however, it has been found that conventional rubber tips possess grave limitations which often result in severe injury to the user.
For example, with most rubber tips the shaft of the cane needs to be held in substantially vertical alignment, so that the contact patch on the bottom of the tip will be able to flatly engage the floor surface. Unfortunately, people frequently hold a cane at an outward angle from their bodies in an effort to steady themselves, so that the shaft extends at an angle to the floor rather than straight up and down. This causes the rubber tip to contact the floor at an angle, with only an edge of the tip engaging the floor surface. Consequently, when the person's weight bears on the cane at this angle, the tip tends to slide out, often causing the person to fall. Naturally, this problem is even more acute if the surface of the is slick or damp.
The problem of the tip slipping out becomes even more problematic when the person rotates the shaft of the cane with the natural motion of their hand/wrist as they walk or move about, since this twists the tip against the floor and tends to break it free from frictional engagement therewith.
Some prior attempts have been made at providing a cane tip which accommodates tilting of the shaft. Examples of these include devices which are shown in the following U.S. Pat. Nos.: 5,307,828 (Gardner et al.); 4,947,882 (Lavasseur); 4,881,564 (Fetterman); 2,419,105 (Allan); and 1,298,713 (Hipwood).
Most of these earlier devices have been too complex and cumbersome to be practical. For example, the Hipwood patent shows a device which provides a tilting and rotating action, but this uses a complex pneumatic mechanism and ball bearing arrangement.
Similarly, the Lavasseur reference shows a cumbersome assembly which employs a ball-and-socket mechanism with a large, domed, elastomeric ring which permits a degree of tilting motion; this device can also be tilted up by stepping on the edge of the base assembly when the cane is lying on the ground (see FIG. 4), but this requires the person to lift their foot a significant distance above the floor and requires a great deal of dexterity.
The Gardner patent shows another complex arrangement, which in this case uses a central plug which is mounted to the cane shaft and connected to a large rectangular pad by a rubber cord. In addition to being cumbersome, the range of motion which this device permits is limited by the elasticity of the rubber cord.
The Fetterman device employs an internal structure in which a soft, cushioning material deforms to accommodate irregularities in the surface or changes in angular orientation. Apart from the complexity and expense which are inherent in this design, deformation of the walls and base of the tip make it difficult for this device to maintain a flat contact surface with the floor under heavy loading. Moreover, the amount of tilting which is permitted by the device depends on the flexibility of the material, and the elastomeric loading of the material at high angular displacements tends to interfere with its ability to maintain stable engagement with the floor.
The Allan device, in turn, has a domed "hat member" which fits within the base of a cane tip having a more or less conventional shape, with a a second washer member on the end of the wooden shaft which rests atop the domed member to provide a rocking action. The upper washer has a downwardly-projecting saw tooth edge, so that this can be removed from the rubber tip and used on icy surfaces. Although this design has the advantage of simplicity, the rubber tip is still friction-mounted on the end of the shaft in essentially the same way as conventional tips, which prevents the shaft of the cane from twisting independently of the tip. Furthermore, like virtually all of the other devices described above, the resistance of the elastomeric member increases steadily with increasing angular displacement of the cane shaft, so that at greater angles the increased elastomeric loading tends to force the tip back towards alignment with the shaft and away from the horizontal plane of the floor. This creates a dangerous situation, since a momentary interruption of the downward pressure on the cane or a slippery surface may allow the tip to spring back towards alignment with the shaft, causing a loss of grip with the floor.
Another problem with existing types of canes is that these are often difficult for the user to pick up in the event that they are accidentally dropped. Since most cane users have impaired physical motions, they frequently lack the physical dexterity to bend over and reach the handle of a cane which is lying on the ground or floor. As was noted above, the device disclosed in the Lavasseur patent does little to alleviate this situation, since it is difficult to use and does not raise the cane handle high enough for this to be reached without having to bend over.
Accordingly, there exists a need for an anti-slip cane tip which is capable of remaining in perpendicular engagement with a floor or other support surface while the shaft of the cane is tilted through a large range of angular displacement. Moreover, there is a need for such a tip which will permit the shaft of the cane to be rotated independently of the tip, so that the user can twist the cane without fear of the tip losing its grip against the floor. Still further, there is a need for such a tip which will accommodate significant angular displacement of the shaft without causing increasing elastic loading of a resilient member which would tend to force the tip away from the plane of the floor. Still further, there is a need for such a tip which is simple and inexpensive in construction, and which employs a conventionally-shaped external rubber tip member so that this can be replaced easily and at minimal cost. Still further, there is a need for a cane having such a tip which can be picked up without the user having to bend over, in the event that the cane is accidentally dropped on the floor or other horizontal surface.

Walking cane assembly having pivoting safety tip


A device, which is intended to remotely control at least one operation of at least one appliance, includes an input interface module for receiving inputs from a user, and a communication module for sending to a management platform data which represent a control instruction activated by the user. Such a device can have universal remote control functionality, with an additional contextualization functionality.

Individuals and companies increasingly need to control appliances which are installed in a variety of premises, such as residential premises or business premises. These appliances are for example rolling shutters, domestic robots, lighting systems, heating systems, ventilation systems, surveillance or security systems, etc. They may belong to the home automation sector or to the economic business sector of the premises. Generally, such appliances can be controlled by separate remote controls which are dedicated to each of them, or by applications which can be accessed on smartphones, or on tablets.
Now, the set of remote controls and applications which are necessary for all the appliances of one and the same premises can be significant in number, such that the use of some of these remote controls or applications becomes a source of confusion, and requires the user to consult manuals each of which is specific to one of the appliances. Significant wastes of time result therefrom.
From this situation, there is therefore a need for a user to be able to easily and rapidly remotely control a multiplicity of appliances.
This need relates more particularly to a common remote control which is compatible with multiple appliances.

Device for remotely controlling an appliance


Undifferentiated primordial stem cells are manipulated to permit their long term growth in defined media lacking serum and feeder layer cells by shifting the apoptotic balance of the cells, through increasing the activity of Bcl-2 family anti-apoptotic proteins or decreasing the activity of Bcl-2 family pro-apoptotic proteins. In some embodiments of the invention, the Bcl family protein is Bcl-2. The ES cells sustain the characteristics of undifferentiated, pluripotent stem cells during long-term serum- and feeder layer cell-free conditions, including the ability to be expanded in vitro, but maintain their potential to differentiate into mature cell types.

Stem cells are defined as cells that, at the single cell level, are capable of both self-renewal and differentiation to specialized cell types. The growth potential of mammalian embryonic stage cells have been known for many years, although the ability to culture such pluripotent and totipotent stem cells, particularly human stem cells, has only been recently developed. Embryonic stem (ES) cells are derived from cultures of inner cell mass (ICM) cells, and have the property of participating as totipotent cells when placed into host blastocysts. The developmental pathways that endogenous ICM cells or transferred ES cells take to tissue formation and organogenesis may be controlled for the development of tissue and organ specific stem cells. The ability of ES cells to grow specialized cells and tissues could provide an unprecedented tool in the clinic, by providing a means for transplantation and repair of damaged muscles, nerves, organs, bones and other tissues. ES cell lines also have a potent ability to replicate in culture, unlike many of the somatic stem cells, which may also be limited to differentiation within specific lineages.
When cultured in vitro, ES cells can self-renew indefinitely in the presence of LIF and fetal bovine serum or mouse feeder layer cells, resulting in daughter cells that maintain their potential for multilineage differentiation. In general, when ES cells are maintained in serum- and feeder-free conditions, the number of undifferentiated cells quickly reaches a plateau and begins to decline after only a couple of passages, and a population of cells with a non-ES cell morphology arises in culture despite the presence of LIF. Thus, additional signals from serum or feeders appear to be required to fully support the self-renewal of ES cells.
Serum and feeder cells may act to provide the survival signals manifest in growth factors and cytokines, and such extrinsic survival signals can be especially critical in low cell density conditions. Where such stimulation through auto- and paracrine factors is inadequate, ES cells may become apoptotic.
It has been suggested that the use of N2 and B27 supplemented media to expand ES cells in serum- and feeder-free conditions improves viability. However, these supplements alone cannot support the self-renewal of ES cells. Further, as N2 and B27 supplements contain hormones (corticosterone, progesterone, and T3) and retinyl acetate, a precursor of retinoic acid, (which components may induce differentiation of ES cells), the presence of these components complicates the analysis of cytokines, growth factors, and chemicals on self-renewal and differentiation of ES cells. To analyze the effect of single cytokines, growth factors, and other molecules on self-renewal and differentiation of ES cells, it would optimal if cells could be protected from apoptotic cell death in serum- and feeder-free conditions.
The therapeutic use of stem cells will benefit from the ability to culture the cells in defined media. Such media may have the advantage of being free from feeder layer cells, which have a potential for virus contamination. Such media may also be free of serum, which adds cost, complexity, and a potential for prion contamination. The present invention addresses this problem.

Feeder layer and serum independent embryonic stem cells

The Board of Trustees of the Leland Stanford Junior University


A low common salt soy sauce, which has good flavor, significantly suppresses elevation of blood pressure, prevents cardiac hypertrophy, and is also available as special nutritious food, is obtained. 1.0% to 10.0% by weight of potassium chloride and 0.1% to 5.0% by weight of γ-aminobutyric acid are added to a reduced common salt soy sauce, so as to obtain a low common salt soy sauce of issue. Otherwise, a KCl-containing low common slat soy sauce is obtained by: (1) a common production method of soy sauce, in which a mixed solution consisting of KCl and common salt is used as mother water; (2) a method of subjecting a soy sauce obtained using saline solution as mother water to electrodialysis, a membrane treatment, or the like, so as to eliminate common salt from the above soy sauce, and then adding KCl thereto; or other methods. Thereafter, γ-aminobutyric acid is added to the above KCl-containing low common salt soy sauce, so as to obtain a low common salt soy sauce comprising 0% to 10% by weight of common salt, 1.0% to 10.0% by weight of potassium chloride, and 0.1% to 5.0% by weight of γ-aminobutyric acid.

Soy sauce, one of typical Japanese condiments, has unique flavor, and thus, it has achieved a new recognition that it is able to exhibit an excellent cooking effect upon Western-style cuisine as well as upon Japanese cuisine. Based on such recognition, soy sauce has been increasingly demanded as a universal condiment in the United States, Europe, Southeast Asia, etc.
In general, soy sauce is produced by inoculating filamentous fungi belonging to genus Aspergillus or the like into a mixture consisting of a protein raw material such as soybeans denatured by heating and a starch raw material such as wheat, culturing the obtained mixture to produce soy sauce koji, adding the koji into saline solution, and then fermenting and aging the mixture, followed by filtration of the resultant.
A main purpose for adding the soy sauce koji into saline solution and then fermenting and aging the obtained mixture is prevention of mash putrefaction during the fermentation and aging process. The concentration of salt in saline solution, into which the koji is added, is generally between 15% and 25% by weight. Using saline solution having such a salt concentration, a soy sauce product having a common salt concentration of 10% to 20% by weight can be obtained.
On the other hand, it is said that excessive ingestion of common salts affects renal disease, heart disease, or hypertension. Since soy sauce contains a large amount of salt, there is a fear that it affects such diseases.
Under the aforementioned circumstances, various types of methods for producing a low common salt soy sauce have been studied. Examples of such a production method that has been attempted may include: a method of using saline solution with a lower concentration, such as a method of using saline solution with a minimum concentration that is necessary for avoiding putrefaction or a method of using alcohol together with mother water; and a method of producing a low common salt soy sauce by eliminating common salt from a soy sauce containing 15% to 18% by weight of the common salt obtained by a common method by means of electrodialysis, a membrane treatment and so on.
Moreover, a method of substituting a portion of common salt contained in a soy sauce with potassium chloride (KCl) has also been proposed.
Examples of such a method that has been proposed may include: an ordinary soy sauce production method, which is devised such that it comprises adding koji to a KCl solution used as mother water instead of saline solution, followed by fermentation and aging, so as to produce a KCl-containing soy sauce that contains no common salts, and at the same time, adding koji to saline solution used as mother water, followed by fermentation and aging, so as to produce a normal common salt-containing soy sauce, and then mixing both types of soy sauces, thereby obtaining a low common salt soy sauce (Patent Document 1); and a method of adding soy sauce koji to a mixed solution consisting of common salt and KCl used as mother water, followed by fermentation and aging, thereby obtaining a low common salt soy sauce (Patent Document 2).
Such a method of substituting a portion of common salt contained in a soy sauce with potassium chloride (KCl) so as to produce a low common salt soy sauce includes easy industrial operations, and thus it is extremely advantageous. On the other hand, KCl has distinctive bitter taste, which brings on a fatal demerit to a soy sauce. Accordingly, this method has been disadvantageous in that the amount of common salt substituted with KCl is consequently restricted.
A method of obtaining special nutritious foods (for example, soy sauce) for patients with hypertension, which uses soybeans, soybean germs, or ground soybeans that contain γ-aminobutyric acid-enriched soybean germs, instead of soybeans (or defatted soybeans), in a common production method of soybean processed foods (for example, soy sauce), has been known. However, it has not yet been known whether or not a soy sauce used for patients with hypertension can actually be produced by this method (Patent Document 3).
According to the studies of the present inventors, if γ-aminobutyric acid is added to a soy sauce and the content thereof is increased, the effect of suppressing elevation of blood pressure can be expected. However, it is hardly to say that such effect is sufficient.
Patent Document 1: JP Patent Publication (Kokoku) No. 38-6582 B (1963)
Patent Document 2: JP Patent Publication (Kokai) No. 56-68372 A (1981)
Patent Document 3: JP Patent Publication (Kokai) No. 11-151072 A (1199)


A ceiling mountable smoke detector with audible alarm including a close-on-temperature-rise heat sensing switch which controls the activation of a solenoid controlled valve placed over the dispensing opening of a pressurized canister of fire extinguishing powder. The smoke detector and alarm function to sound an alarm upon sensing smoke. When smoke is being sensed simultaneously with sufficiently high heat around the smoke detector, the heat sensing switch closes to allow the activation and opening of the solenoid valve at which point fire retardant is dispersed in the immediate area. The smoke detector, audible alarm, the heat sensing switch, and the solenoid valve and fire retardant canister are built into a single easily installed assembly which may be mounted during new construction prior to the finished ceiling being applied, or may be installed as a "cut-in or remodeler unit" after the ceiling has been applied. When installed, the unit is semi-flush, having a significant portion of the unit above the finished ceiling while leaving only a relatively small and unobtrusive decorative trim plate of the unit exposed in the room through which the fire retardant is dispersed.

1. Field of the Invention
This invention relates to safety devices and fire fighting equipment in general, and particularly to a smoke detector with audible alarm and fire extinguishing capabilities in a single, easily mounted housing.
2. Description of the Prior Art
Smoke detectors with audible alarms have been required in most residences in the U.S. for quite a few years. Typical smoke detectors with alarms are complete assemblies or units in a single small housing. The housing normally includes the smoke detecting and audible alarm electronics, a power supply for conditioning and directing the proper electrical power from 120 volts AC or 9 volts DC to the electronics, and also an alarm horn or buzzer, and all contained within the small housing structure attachable to an electrical box or directly to the ceiling. Typical smoke detectors function to sense smoke either by sensing atomic particles using an ionization process, or by seeing smoke particles using a photoelectric process. With either sensing process, when smoke is detected, the smoke detector triggers an audible alarm intended to awaken or alert the occupants of the danger. If the residence is empty, such as when the owners are at work, the audible alarm is normally not sufficiently loud to alert the neighbors, and this being in-part due to the audible alarm normally stemming directly from the smoke detector unit within the interior of the residence, and consequently, a fire can become quite large before being noticed.
There is a trend in the U.S. to render residences more safe against all hazards, including fire and smoke hazards. This trend in some areas is leading to the increased mandating of automatic fire-extinguishing water sprinkle systems, even in single story buildings. Such sprinkle systems in the past were normally only required in multi-story apartments and condominiums, and in commercial/industrial buildings. Although water sprinkle systems are effective at slowing or extinguishing fires in the immediate area of the sprinkler head(s), they are costly to install, and particularly costly to install after the building has been completed, such as during a remodel when the finished ceiling is already in place. Additionally, if the sprinkler system is triggered, water from the system will mix with smoke causing a mixture which is very damaging to the building and furniture, and therefore water or liquids are not the ideal fire retardant from that view point.
Several combination smoke detector with fire extinguisher units have been developed in the past which use dry powered or gaseous fire retardants which are less damaging to the building and furniture than water because they are dry and can simply be vacuumed up. However, none of the prior art combination smoke detector with fire extinguisher units of which I am aware are structured the same as the present invention, and none are believed to be capable of providing equal benefits in similar applications as the invention of this disclosure.

Ceiling mountable smoke detector and fire extinguisher combination