A switching power converter may include a power switch coupled to a primary winding of a transformer, and a primary controller configured to turn on and off the power switch, a synchronous rectifier switch coupled to a secondary winding of a transformer, and a synchronous rectifier controller configured to turn on and off the synchronous rectifier switch. The synchronous rectifier controller may monitor a voltage across the synchronous rectifier switch. The synchronous rectifier controller may detect a fault condition responsive to the voltage reaching a turn-off voltage threshold before a minimum on-time timer expires. The synchronous rectifier controller may detect a fault condition responsive to the synchronous rectifier switch being turned off at the same time, immediately after, or within a timing guardband after the minimum on-time timer expires. The synchronous rectifier controller may adaptively increase a minimum off-time period for the synchronous rectifier switch.

The explosive growth in mobile electronic devices such as smartphones and tablets creates an increasing need in the art for compact and efficient switching power converters so that users may recharge these devices. A flyback switching power converter is typically provided with a mobile device as its transformer provides safe isolation from AC household current. A conventional flyback converter that uses a rectifying diode at the secondary (load) side of its transformer has significant power loss due to a relatively high forward voltage drop in the rectifying diode. Thus, synchronous rectification techniques have been developed that replace the rectifying diode with an actively controlled switch such as a field-effect transistor (FET) device (e.g., a metal oxide field-effect transistors (MOSFET) device) to improve operating efficiencies by taking advantage of its lower power losses.
Conventional flyback converters with synchronous rectification typically include a synchronous rectifier controller that controls the synchronous rectifier switch (S2) based on a voltage across the synchronous rectifier switch terminals. When this voltage falls below an on-time threshold voltage, the controller switches on the synchronous rectifier switch S2 so that power is delivered to load. During this power delivery, the voltage across the synchronous rectifier switch S2 gradually rises above the on-time threshold voltage until it crosses an off-time threshold voltage. This off-time threshold voltage corresponds to the voltage across the synchronous rectifier switch at the transformer reset time when the secondary winding current has ramped down to zero.
The timing of the on and off states for the synchronous rectifier switch is critical to reduce losses. But the control with regard to the on-time and off-time threshold voltages is problematic because the voltage across the synchronous rectifier switch S2 will have a resonant oscillation at the switch on times and off times due to parasitic effects. When the synchronous rectifier switch S2 is switched on, this resonant ringing could cause the switch voltage to exceed the off-time threshold voltage such that the controller would undesirably switch off the synchronous rectifier switch even though the secondary winding current is still relatively robust (it being well before the transformer reset time). To prevent such an undesirable premature cycling off of the synchronous rectifier switch S2, it is conventional for the controller to apply a minimum on-time period with regard to monitoring the off-time threshold voltage following the cycling on of the synchronous rectifier switch S2. During this minimum on-time period, the controller does not respond to the synchronous rectifier switch S2 voltage exceeding the off-time threshold voltage.
An analogous minimum off-time period follows the cycling off of the synchronous rectifier switch S2 to prevent the controller from responding to a resonant oscillation of the switch voltage that causes the switch voltage to fall below the on-time threshold voltage. But in contrast to the resonant oscillation that occurs at the synchronous rectifier switch S2 on-time, the resonant oscillation at the switch off-time is markedly more robust and prolonged. This robust off-time oscillation of the switch voltage complicates the setting of an appropriate duration for the minimum off-time period that may be better appreciated through a consideration of the waveforms shown in FIG. 1 for a power cycle 110 and a power cycle 120 of a primary-side power switch S1. In this example, the voltage across the synchronous rectifier switch S2 is a drain-to-source (VD-S) voltage for a MOSFET. In response to the cycling off of power switch S1, the drain-to-source voltage for synchronous rectifier switch S2 falls below the on-time threshold voltage. The synchronous rectifier switch S2 is thus switched on while at the same time a timer (S2 Min TON Timer) is started to time the minimum on-time period. The resulting resonant oscillation of the drain-to-source voltage is relatively minor and quickly damped such that the duration of the minimum on-time period may be relatively short.
In response to the cycling on of the synchronous rectifier switch S2, the secondary winding current pulses on and begins to ramp down until it reaches zero at the transformer reset time (T1 Reset). At the same time, the drain-to-source voltage for switch S2 rises above the off-time threshold voltage (S2 OFF Threshold) such that the S2 switch is switched off and a timer (S2 MIN TOFF Timer) begins timing the minimum off-time period. The resulting resonant oscillation for the drain-to-source voltage following the synchronous rectifier switch S2 off time is more pronounced and slower to damp as compared to the damping that occurs at the on time for synchronous rectifier switch S2. For power cycle 110, the minimum off-time period has a proper duration such that the resonant oscillations of the drain-to-source voltage do not cross the on-time threshold voltage following the termination of the minimum off-time period.
But the resonant oscillations following the synchronous rectifier switch S2 off time are more pronounced for a subsequent power cycle 120 of power switch S1. Due to this more pronounced resonance, the drain-to-source voltage crosses the on-time threshold voltage at a time 122 following the termination of the minimum off-time period in power cycle 120. As a result, the controller cycles the synchronous rectifier switch S2 on despite there being no power pulse to deliver. The result is that the secondary winding current has a slightly negative value during the minimum on-time period following time 122. Upon the termination of this undesirable minimum on-time period, the drain-to-source voltage exceeds the off-time threshold voltage such that the synchronous rectifier switch S2 is cycled off for another minimum off-time period. But the subsequent resonant oscillation of the drain-to-source voltage again causes the drain-to-source voltage to cross the on-time threshold voltage such the synchronous rectifier switch S2 is again cycled on a time 124. Another negative current is induced on the secondary winding until the termination of the subsequent minimum on-time period whereupon the drain-to-source voltage again exceeds the off-time threshold voltage such the synchronous rectifier switch S2 is opened.
The resulting cycling on and off of the synchronous rectifier switch S2 following the transformer reset time is undesirable for a number of reasons. For example, the negative current excited across the secondary winding wastes power. More fundamentally, the synchronous rectifier switch S2 may be cycled on when the power switch cycles on, which is a severe problem. The prior art setting of the minimum off-time period is thus problematic in that it cannot be set too short or this undesirable cycling of the synchronous rectifier switch S2 occurs yet it cannot be set too long in that the minimum off-time period would then interfere with the next power switch S1 cycling.
Accordingly, there is a need in the art for improved synchronous rectifier control techniques for switching power converters.

Minimum off-time adaptive to timing fault conditions for synchronous rectifier control


Methods and systems for the production of alcohols are described. A two stage process is utilized, where fermentation in a first stage produces an intermediate product, such as an amino acid or organic acid, from a carbon containing feedstock. A second stage produces alcohol by fermentation of this intermediate product.

Butanols are an important class of chemicals with utility in a wide range of industrial applications, including use as a solvent and reactive intermediate in organic syntheses, as a solvent in the textile industry, as an extractant in the food industry, and as a slow-evaporating solvent for use in enamels and lacquers. Recently butanols (such as isobutanol) are finding increasing use as an alternative to conventional fossil fuels for use in motor vehicles. Unlike ethanol, such butanol fuels are not corrosive, offer an energy density similar to that of gasoline, and can be used as a direct replacement for petroleum-derived fuels in motor vehicles without the need for extensive engine modifications. Branched chain alcohols, such as isobutanol, 2-methyl-1-butanol, and 3-methyl-1-butanol are particularly attractive in this regard. Currently 10 to 12 billion pounds of butanol are produced annually and needs are projected to increase.
In the United States butanols are generally produced by the hydroformylation of propene to form butyraldehyde, which is subsequently reduced to 1-butanol and 2-butanol. Such process, however, relies on nonrenewable resources and result in the release of greenhouse gases to the environment. As a result methods for the production of butanols have been developed that utilize biological processes and renewable starting materials such as biomass.
Butanol production using biological means, also known as biobutanol, is well known. For example, butanol was noted as a byproduct of the A.B.E. process developed by Chaim Weizmann nearly a century ago, in which acetone is produced by fermentation of starch by Clostridium acetobutylicum. Production of butanol by this process is low, however. More recently a number of investigators have proposed methods for higher yield production of butanols through the use of genetically modified organisms that ferment simple or crude feedstocks. For example, United States Patent Application No. 2009/0081746 (to J. C. Liao et al.) describes use of a variety of genetically modified organisms with mutations in specific metabolic pathways to ferment sugars and produce a variety of higher alcohol biofuels. Similarly, United States Patent Application No. 2009/0288337 (to S. Picatoggio et al.) discloses the use of genetically modified organisms, such as yeasts, to produce methylbutanol biofuel from amino acid precursors. Such approaches, however, necessarily suffer from relatively low yields that limit their use in large scale operations. Such low yields can be due to metabolic bottlenecks inherent in the enzymatic pathways used. For example, in United States Patent Application No. 2008/261230 (to D-I. Liao, M. J. Nelson, and M. G. Bramucci) it was noted that enzymes in these metabolic pathways may be engineered for high expression in a genetically modified organism, but still remain bottlenecks in a fermentative process due to inherent low specific activity for the production of isobutanol. Since isobutanol and similar compounds are relatively toxic it is not clear if enzymes are or will be available with specific activities high enough to support industrial synthesis of butanols at the relatively low concentrations of butanol precursors generated within a living cell. These and all other extrinsic materials discussed herein are incorporated by reference in their entirety. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
In another approach (as disclosed in U.S. Pat. No. 8,293,509, to S. D. Simpson et al.), a first bioreactor can be used to produce useful alcohols from a crude feedstock and to produce a side product that can be used to enhance the production of butanol from a second, distinct feedstock (such as a carbohydrate) within a second bioreactor. In all of these approaches, however, the inherent toxicity of higher alcohols such as butanol and isobutanol can limit their final concentration in a conventional fermentation process via growth inhibition, metabolic inhibition, and/or death of the productive cells.
Attempts have been made to address the problem of product toxicity in the biological production of butanols. For example, U.S. Pat. No. 8,283,144 (to G. K. Donaldson et al.) describes the use of organisms with resistance (i.e. IC50>0.5% w/v) to isobutanol to produce this product by fermentation of sugars. Similarly, United States Patent Application No. 2007/259411 (to M. G. Bramucci et al) discloses a method for improving the resistance of butanol-producing Enterococcus strains evolutionary means and their subsequent use in the synthesis of butanol and isobutanol. It is not clear, however, if the concentration of these higher alcohols that can be tolerated are economically recoverable at large scale. Another approach is suggested in United States Patent Application No. 2008/274526 (to M. G. Bramucci et al.), in which the temperature of the fermentation process is reduced in order to improve tolerance to the isobutanol product. Such a reduction in temperature, however, both reduces the rate of isobutanol production and can increase energy costs.
Yet another approach to reducing the effect of product toxicity is to provide a means for segregating biologically produced butanols from the sensitive cell population. One method, disclosed in United States Patent Application (No. 2011/097773, to M. C. Grady et al.), is to provide a water-immiscible solvent system that extracts 1-butanol, 2-butanol, and isobutanol from fermentation media. Large scale application of this approach is limited, however, by the need to occupy a relatively large portion of the fermenter volume with the non-productive solvent system. An alternative approach is disclosed in European Patent No. 0,047,641B1 (to H. G. Lawford), in which the fermentation process is split into an initial phase where little alcohol (in this instance ethanol) is produced and cells replicate rapidly and a second phase where growth-inhibiting concentrations of alcohol are produced by the culture amassed during the initial phase by changing culture conditions. Such an approach, however, retains the metabolic limitations of performing a complete fermentative process within a single organism.
Thus there remains a need for efficient and scalable biological synthesis of alcohols, and particularly branched chain butanols, from simple feedstocks.


A refuse container has a lid that is hinged thereto without the use of mechanical fasteners. The container has short shafts extending therefrom. The lid has arms that pivotally receive and are captured on the container shafts. The shafts are formed with sectors, and the lid arms have recesses that receive the sectors. The lid arms recesses define stepped surfaces located at predetermined locations relative to the container sectors so as to positively stop the lid at a desired open position. The lid arms may be formed with dual radius recesses connected by a flat surface. The container sectors and the recess surfaces are dimensioned to enable the lid to be freely pivoted to an intermediate open position approximately 90.degree. from a closed position and subsequently in a controlled manner to a third open position approximately 270.degree. from the first position. The mold for making the container and lid has a flat parting surface.

1. Field of the Invention
This invention pertains to waste handling, and more particularly to apparatus for temporarily storing waste materials.
2. Background of the Invention
Various types of receptacles have been developed to temporarily store and transport waste products. For example, receptacles that include a wheeled container for holding the refuse and a lid pivotally connected to the container are well known. Some types of receptacles are designed to be handled and emptied by automatic equipment. Typical examples of prior receptacles are shown in U.S. Pat. Nos. 4,450,976 and 4,749,101.
The receptacle lids may be retained on the containers by various means, such as mechanical fasteners. On the other hand, the lid may be hinged directly to a handle that is an integral part of the container. In some designs, the lid is pivotable from a closed position overlying the top of the container through approximately 100.degree. to an open position whereat it is generally vertical and above the hinge. In other receptacles, the lid is pivotable from the closed position through approximately 270.degree. to an open position whereat the lid is generally vertical and below the handle. Ideally, a single lid is selectively openable to both the 100.degree. and the 270.degree. positions.
However, prior receptacles employ rather makeshift designs for enabling the lids to have 100.degree. and 270.degree. stop positions. In some cases, the 100.degree. stop is achieved by manually moving the lid pivot point such that the lid strikes the container handle to provide the stop. In prior receptacles, swinging the lid from the 100.degree. position to the 270.degree. position is uncontrolled, and the rapidly rotating lid tends to strike the bottom of the container and tip the container over as the lid approaches its lowermost position.
An additional disadvantage of prior receptacles is that it is difficult to satisfactorily convert a container and lid having a 100.degree. lid opening to one with a 270.degree. opening. Consequently, a user must order and stock two entirely different receptacles if he has applications requiring both openings.
Thus, a need exists for improvements in refuse receptacles.


A locomotive traction controller system using fuzzy logic to maximize the coefficient of friction between locomotive drive wheels and the rail on which the wheels ride. The locomotive traction system includes a fuzzy logic slip controller that provides a generator reference signal to a generator controller that controls the field current of the generator of the locomotive. The fuzzy logic slip controller regulates to a predetermined wheel slip regardless of the rail condition. A fuzzy logic slip reference estimator applies a wheel slip reference signal to the fuzzy slip controller depending on the rail condition in order to adjust the generator reference signal and thus modify the wheel slip to maximize the coefficient of friction.

1. Field of the Invention
This invention relates generally to a traction control system and, more particularly, to a traction control system using fuzzy logic to control wheel slip of the drive wheels of a train locomotive in order to maximize the coefficient of friction between the drive wheels and the rail interface.
2. Discussion of the Related Art
As is well understood, train locomotives, such as diesel electric locomotives, used to move railway cars along a dual rail configuration are propelled by exerting torque to drive wheels associated with the locomotive that are in contact with the rails. The power to propel the locomotive is first developed as mechanical energy by a high horsepower diesel engine. The diesel engine drives a generator that converts the mechanical energy to electrical energy. The electrical energy is then converted back to mechanical energy by a series of traction motors. One traction motor is rigidly connected to each axle associated with a pair of drive wheels such that when the axle is rotated, the drive wheels also rotate. In this manner, each traction motor is in parallel with the generator and rotates independently of the other axles. The specifics of the mechanisms for propelling a locomotive are well known.
Friction between the drive wheel and the rail interface provides the traction for causing the movement of the locomotive. If there were no friction between the drive wheels and the rail surface, the wheels would rotate and slip relative to the rails without providing movement to the locomotive. The friction force is a function of the coefficient of friction between the drive wheels and the rail interface, and the downward force exerted by the locomotive on the rail. Wheel slip is the value that characterizes the difference in linear speed between the locomotive and the drive wheels. The more friction between the drive wheels and the rail surface, the more traction can be generated, and thus, the more propelling force is available to move the locomotive. It is possible to increase the friction force between the drive wheels and the rail surface by increasing the weight of the locomotive. However, certain well understood engineering and economic factors make this option unattractive. Therefore, locomotives incorporate traction control systems in order to maximize the friction force between the drive wheels and the rail surface, so as to maximize the propelling force of the traction motors.
A traction control system may have two control variables that can be used to control the amount of wheel slip of the drive wheels relative to the rails. First, the power output of the generator can be reduced, which leads to lower traction motor torques, which in turn leads to less force causing the drive wheels to spin. However, reduced generator power provides less power to propel the locomotive. Second, the locomotive can drop sand in front of the wheels, thus creating a greater friction relationship between the drive wheels and the rail surface. However, limited payload and cost of sand require that this method of control be used conservatively. Consequently, the only practical way to maximize the friction force is to maximize the value of the coefficient of friction between the drive wheels and the rails.
When torque is applied to the drive wheels during operation of the locomotive, the wheels will begin to slip at an increasing rate until the slip reaches an equilibrium wheel slip level when the torque acting on the wheels balances out. More or less torque will cause the wheels to slip at a different rate, thus changing the time at which equilibrium is reached. If the friction/slip relationship between the drive wheels and the rail interface increased monotonically, no control system would be required. Under most rail conditions, however, the graphical relationship between the coefficient of friction and the wheel slip reaches a peak at a location depending on the torque being applied and other system conditions, and then declines.
FIG. 1 shows a graphical relationship between the coefficient of friction on the vertical axis and the percent of wheel slip on the horizontal axis for dry, wet and oily rail conditions. A graph line for each coefficient of friction versus percentage of wheel slip is given for the different rail conditions in each direction of rotation of the drive wheels. As is apparent by viewing FIG. 1, under dry rail conditions, the coefficient of friction is at its maximum at about 10% wheel slip. It is noted that under ideal dry rail conditions, the torque that a locomotive engine can generate is not high enough to cause the wheel slip to increase to this value. Once the rail becomes wet and/or oily, the percentage of wheel slip at which the maximum coefficient of friction is attained increases. Particularly, for a wet rail condition, the maximum coefficient of friction is at approximately 15% wheel slip. For oily rail conditions, the maximum coefficient of friction is given at about 30% wheel slip. Wheel slip above 25%, however, can cause excessive wear or even damage to both the wheels and the rail. The region of each graph line before reaching the peak is a stable region of operation, however, the region of each graph line beyond the peak is an unstable region in which predictable wheel rotation is indeterminable.
The goal, therefore, of a traction control system that attempts to maximize the coefficient of friction is to operate as close to the peak of the friction/slip curve as possible, while avoiding the unstable region. The general strategy of the traction control system is to estimate the slip level at which the friction/slip curve reaches its peak value, and to regulate the system so that the wheel slip does not exceed this value. When the wheel slip is close to the unstable region, control action must be taken to remain in the stable region. This task is made more difficult because the exact characteristics of the friction/slip curve is never known as rail conditions can rapidly change causing the estimated peak to be at a higher slip value than the actual peak. Abnormal rail conditions may cause a friction/slip characteristic that increases asymptotically to a maximum coefficient of friction. A traction control system must limit wheel oscillation while correcting the estimation of the friction/slip curve peak.
Prior art traction control systems generally consist of cascaded single input and single output controllers. The innermost controller loop controls the generator's field current by varying the generator's field voltage source. A reference field current is generated by a generator output controller for establishing the generator field current. The generator output controller regulates the generator so the generator's operating characteristics follow a desired pattern based on a system model of the locomotive. The system model would include a generator model, a generator field model, and a model representing the field current controller and the generator output controller. A simplification can be made because the closed loop response of the actual generator controller is known.
Traction control system models which define the rotation of an axle generally assume that the wheels associated with an axle rotate at the same angular velocity and experience the same coefficient of friction. In reality, differences in the coefficient of friction exist between the two wheels of an axle exists such that torsional forces are generated in the wheel axle and differing angular velocities occur for the two wheels.
Because of the many factors which effect the friction/slip relationship, it is necessary to incorporate traction control models that are robust enough to compensate for these variances so as to increase the coefficient of friction between the drive wheels and the rail interface. It is therefore an object of the present invention to provide a traction control system with increased capabilities over the prior art systems.

Locomotive traction control system using fuzzy logic


Methods for performing change of primary cell during carrier aggregation operation are described. A mobile station (MS) receives a message to change a primary cell and to perform a random access communication with a new primary cell. Upon receiving a random access response message from the new primary cell, the MS starts transmitting a control channel to the new primary cell. In one embodiment, the MS releases the configuration of an uplink control channel and transmits uplink control information through an uplink shared channel. Upon completion of the primary cell change procedure, the MS starts transmission of an uplink control channel to the new primary cell.

Carrier Aggregation will be used in 3GPP LTE networks to provide improved data rates to users, which are also referred to as a mobile station or as user equipment (UE). Carrier aggregation consists of transmitting data to or receiving data from a UE on multiple carrier frequencies ("component carriers"). The wider bandwidth enables higher data rates. The present disclosure considers the problem of change of the primary cell of a mobile station. For carrier aggregation (CA) operation, a UE can be configured with a set of serving cells. Each of the serving cells has a downlink frequency and may also have an uplink frequency. The downlink frequencies of the different serving cells of a UE are distinct and the uplink frequencies of a UE are distinct. In the case of a frequency division duplex (FDD) system, the downlink and uplink frequencies of a serving cell are distinct. In the case of a time division duplex (TDD) system, the downlink and uplink frequencies of a serving cell are the same. Carrier aggregation operation can also be described in terms of "component carriers" or "serving frequencies". The mobile station has a set of "downlink component carriers" or "downlink serving frequencies" (corresponding to the downlink frequencies of the serving cells) and uplink component earners or. "uplink serving frequencies" (corresponding to the uplink frequencies of the serving cells). In general, all the serving cells of a mobile station belong to the same base station (that is, all the downlink frequencies are transmitted from the same base station). However, there can be exceptions to this rule. For example, in a base station can transmit one or more downlink serving frequencies, while the remaining downlink serving frequencies are transmitted are transmitted by one or more remote base station equipment.
One of the serving cells is designated as a "primary cell". Correspondingly there are "downlink primary frequency" and "downlink primary component carrier" which refer to the downlink frequency of the primary cell, and "uplink primary frequency" and "uplink primary component carrier" which refer to the uplink frequency of the primary cell. A serving cell that is not a primary cell is referred to as a secondary cell.
The communication link between the mobile station and the primary cell is a primary link in the communication between the mobile station and the network. Specifically, at the time of connection establishment between the mobile station and the network, a bi-directional communication link between the mobile station and the primary cell is established before any communication link is established between the mobile station and a secondary cell.
Carrier Aggregation procedures are designed such that the mobile station transmits the uplink control channel only to the primary cell (i.e., only on the uplink primary frequency). The uplink control channel carries various control information such as ACK/NACK indicators for downlink transmission from all serving cells, Channel Quality Indicator (CQI) information for all serving cells and scheduling requests (SR). Thus any interruption of uplink transmissions from the mobile station to the primary cell effectively results in interruption of almost all downlink communication (including all user data communication) through all of the serving cells.
If the communication link between the mobile station and the primary cell is interrupted, the communication between the mobile station and the network fails even if the communication link between the mobile station and a secondary cell is sustained. The primary cell provides security and encryption related information to the mobile station. Furthermore, the mobile station performs radio link monitoring of the primary cell but not of the secondary cells. If the radio link monitoring of the primary cell indicates that there is a radio link problem, the mobile station suspends all reception and transmission of signals. If there is no recovery from the radio link problem, the mobile station declares a radio link failure, breaks the connection to the serving cells and attempts to re-establish the connection to the network through a suitable cell. Such actions can result in significant interruptions of the communication link and also in irrecoverable failure of the communication link.
Given the importance of the link between the mobile station and the primary cell, in order to minimize problems associated with radio link quality, it is necessary to ensure that the primary cell is the best cell of the serving cells. Such a requirement then makes it necessary to change the primary cell when the primary cell is no longer the best cell. Change of the primary cell can be achieved by emulating a handover procedure, wherein the source cell is the current primary cell and the target cell is the new primary cell. However, such a procedure has significant drawbacks. The handover procedure is designed for mobility—that is, for transferring a mobile station from a cell at a first base station (source cell) to a cell at a second base station (target cell). Thus, the mobile station has to perform synchronization to the target cell before communication via the target cell can resume. In 3GPP LTE, the synchronization is performed by a random access procedure, i.e., transmitting on a random access channel and receiving a random access response. The synchronization procedure results in a significant interruption. Since the interruption includes an interruption of uplink transmission to the primary cell, it results in interruption or suspension of all downlink data between the network and the mobile station (as described above). Furthermore, the various communication protocols (such as medium access control and radio link control) and in the mobile station have to be reset and re-established before communication can resume through the target cell. The security key is also changed at the handover. The re-establishment of the protocols and the change of the security key can result in loss of any buffered packets at both the base station and the mobile station.
Therefore it is beneficial to have procedures for change of primary cell that remedy the deficiencies outlined above.

Method and apparatus for change of primary cell during carrier aggregation


A dc power supply (1) for a dc arc torch (6) comprising: an input port (4, 8) for connection to a source of direct current and an output port for connection to the electrodes (5, 7) of an arc torch; a controlled switch (2) and an inductance (3) connected in series between the input port and the output port; a free-wheeling diode (9) connected such that, in use, it is reverse biased when the switch (2) is ON, and forward biased when the switch (2) is OFF to maintain direct current flow through the arc and the inductance (3); and a feedback circuit (10) having a current sensor (11) to sense the instantaneous value of current flowing through the arc, and a control terminal (26) connected to the switch (2), the feedback circuit, in use, operating to provide a control signal at the control terminal (26) to turn the switch (2) ON when the instantaneous value reaches a first level and OFF when the instantaneous value reaches a second level.

A known power supply employs a thyristor, or a silicon controlled rectifier (SCR), in each phase of an alternating current main supply. At least two of the thyristors are always ON at any given time to conduct current to an inductor which stores energy and smooths the output. The other thyristors are sequentially turned ON, to control the average current flow, by means of a predictive control circuit, which attempts to predict the current demand over the following cycle. The thyristors are turned OFF by the next current zero to arrive.
This supply has a number of disadvantages. The first is that control is only exercised over the current at the times when the thyristors are being turned ON. This implies an average delay in the current control of a third of a period of the supply (when a thyristor is used in each phase of a three phase supply). It follows that there is a maximum rate at which current can be controlled. As a result, the inductance must be large enough to limit current ripple at higher rates. This is essential because current zeros extinguish the arc and high current peaks lead to electrode degradation. For example, a 50 kW arc torch consuming 200 Amps will need an inductor of 20 mH, which would weigh several tons, to limit current ripple to less than 50 Amps. This adds greatly to the expense of the power supply.
A second disadvantage arises from the fact that the switching control is predictive and results from a calculated guess rather than being absolutely determined from the current actually flowing at any given time.

The University of Sydney The Electricity Commission of New South Wales


A device for separating liquid particles from an entraining gas or vapor stream. The device employs mechanical centrifugal forces to concentrate liquid droplets in a limited space for further extraction from the gas flow using an electrical field and an electrically charged collecting surface whereby the particles are attracted to and deposited on the surface for further extraction by the gas flow without reintrainment of the liquid back into the vapor stream. The device is constructed to provide an area of low gas velocity for removing the liquid from the device.

Many types of industrial, commercial and even residential technical processes and apparatuses have vapor or gaseous flow streams in which liquid particles of various sizes are entrained. In some of these, the presence of the liquid particles negatively affects the apparatus longevity, the apparatus efficiency or possibly even human health.
The following paragraphs describe examples of such systems and such processes where the invention described and claimed herein can profitably be employed.
Air compressed by air compressors and subsequently cooled frequently has water particles entrained with the air. In one application the water particles enter tools causing corrosion and bearing damage. Other applications find the water separating in a compressed air reservoir or tank where the pooled water, if not drained, causes corrosion that weakens the tank walls, leading to potential catastrophic failure.
Refrigeration systems employ compressors lubricated by oils that, in varying amounts are always entrained with the compressed refrigerant discharged by the compressor. The oil lost from the compressor, if not replaced, can lead to compressor destruction from lack of lubrication. The oil conveyed through the system also causes loss of heat transfer capability in both the evaporator and the condenser.
Oil return in miscible oil-refrigerant systems is generally reasonably reliable because the viscosity of oil conveyed within the system has been lowered by a solution of the refrigerant into the miscible oil. By contrast, oil return in systems employing an immiscible oil-refrigerant pair is much less reliable because the solubility of the refrigerant in the oil is slight and therefore the oil retains its original higher viscosity making flow much less certain. While the system piping can be designed to provide sufficiently high vapor velocities to achieve reasonably satisfactory oil flow, there is a penalty of higher gas pressure drop resulting in reduced system efficiencies. In such refrigeration systems employing immiscible refrigerant-lubricant pairs, discharge line oil separators having the highest efficiencies provide a definite advantage. Moreover, drops of liquid refrigerant in the inlet of a refrigerant vapor pump or compressor can cause damage to the compressor. Therefore, such damage must be avoided by preventing liquid drops of a refrigerant from entering into the compressor inlet.
Comfort air conditioning systems lower air temperature and thereby cause moisture condensation. Some of the condensed moisture is carried along with the cooled airstream into the cooled space, thereby causing discomfort, damage to fabrics and furniture and damage to sensitive electronic equipment, where these are located within the cooled space.
To cope with these problems or other problems arising from liquid carry over in vapor streams, many types and designs of mechanical separators have been designed and many are offered commercially for specific uses. The following types are primarily descriptive of those available for use in refrigeration systems to minimize oil carryover in the compressor discharge stream. Some simply reduce the vapor velocity so that liquid particles settle out. Others swirl the gas to provide at least partial centrifugal separation, some provide baffles to secure separation by impingement, some provide fills or meshes which filter or otherwise trap liquid particles on the meshes or in the mesh interstices. However, all these designs have the fault that very small oil particles and liquid droplets escape through the separator and are carried into the refrigeration piping. Further, no special oil separator designs are suggested or provided for immiscible oil-refrigerant systems.
Objectives of this invention are focused on enhancing efficiency of liquid particle separation from a flowing vapor stream using electrical forces alone or a combination of electrical forces and centrifugal forces. The electrical forces are variously known as Electrostatic (ES) when applied to static situations and Electrohydrodynamic (EHD) when applied to situations involving their effects on moving fluids and on the solid and liquid particles carried by such moving fluids.
In accordance with a first objective, the invention provides separation of liquid droplets from a vapor/gas flow (or flow stream) by a system of electrically charged electrodes and electrical fields associated with those electrodes.
In accordance with a second objective, the invention provides a liquid/gas separator in which centrifugal forces are used to concentrate liquid drops close to a collecting electrode.
In accordance with a third objective, the invention provides electrical charging of liquid droplets in a gas flow stream by a first electrode.
In accordance with a fourth objective, the invention provides collection of liquid droplets on the surface of a second electrode within the gas flow stream.
In accordance with a fifth objective, the invention provides separation of liquid droplets from a vapor/gas stream by moving liquid droplets collected on the surface of the second electrode along the surface of the electrode from a region of higher vapor velocity to a region of lower vapor velocity.
Thus, the invention combines a mechanical centrifugal concentration of liquid droplets with electrical separation of said liquid droplets from the gas flow combined with removal of the separated particles from a region of higher vapor velocity to a region of lower vapor velocity, thereby minimizing reentrainment of the removed particles into the flow stream.
In accordance with a sixth objective, the invention provides a device for modifying the initially straight vapor flow into a twisted one in order to subject the liquid particles to a centrifugal force whereby the liquid droplets are concentrated close to the surface of the second collecting electrode.
In accordance with a seventh objective, the invention provides the second collecting electrode with an electrical field or potential of a character designed to attract liquid particles charged by the first electrode.
In accordance with a eighth objective, the invention provides a combination of charging and collecting electrodes in series.
Further objectives include providing a highly efficient device for separating liquid particles from a flowing vapor stream.
Providing such a device that is mechanically simple and easy to fabricate.
Providing such a device that employs means for imparting a high electrical potential or charge of a first polarity to the gas stream and the liquid particles entrained with the gas stream.
Providing such a device where the polarity of the electrical potential is uni-polar, that is non-alternating.
Providing such a device where the potential imparting means is substantially adjacent the device inlet.
To provide such a device having charged means of a second polarity for attracting the particles charged with the first polarity.
To provide such a device where the particle attracting means includes a cylindrical flow means having an electrical potential substantially equal to and of opposite polarity to the potential applied to the particles.
To provide such a device including at least two coaxial spaced apart cylindrical flow means.
To provide such a device including seriatim in the vapor flow stream a first electrode having a first polarity for initially charging liquid particles, a second electrode having a second opposite polarity for collecting some particles, a third electrode for charging remaining particles with the second polarity and a fourth electrode having the first polarity for attracting substantially all the remaining particles.
A device for separating liquid particles from a flowing gas stream, the device comprising seriatim: an inlet for receiving the liquid bearing gas stream, an element positioned in the flow stream bearing a signed electrical charge for charging the gas borne liquid particles, a second element positioned in the flow stream bearing an oppositely signed electric charge for attracting and receiving the liquid particles and conveying said particles out of the gas flow stream.


An LED light string includes series-connected groups of individual LEDs or sets of LEDs, with each LED or set of LEDs in each group being electrically in parallel with each other LED or set of LEDs and with a parallel group device that regulates voltage within the group when LEDs in that group fail. The current to the LEDs is rectified, either in the light string plug or receptacle, preferably the latter. The color of each light in the group, or colors of each set in the group must be the same but successive groups can include LEDs of different colors. In an alternative embodiment, the LEDs can be oriented so that half light on during the first half of an alternating current cycle and the other half light during the second half of an alternating current cycle.

The present invention relates generally to strings of holiday lighting such as those used for decorating Christmas trees.
Strings of lights, that is, plural lights wired together to be powered from a plug inserted into a wall outlet, are used to decorate Christmas trees and homes. They are used for both interior decorating and exterior decorating.
For a 100-lamp light set, there are typically two types: two series circuits and three series circuits. The light sets both work the same, but the difference between the two is the brightness. One type is normal brightness and the other type is referred to as "super" bright. The difference in lamp brightness is attributable to the lamp voltage. The two series circuits have a lower lamp voltage per lamp (2.5V) i.e. 125/50. Each series circuit has 50 lamps.
The three circuit set has a higher per-lamp voltage of (3.5V) i.e. 125/35, for a much higher voltage and brighter lamp. Each circuit has 35 lamps in it. This means that a "super bright" 100-light set actually has 105 lamps in it.
Prior art light strings have the following parts: (1) an AC plug containing two 3 Amp fuses with 1 line side and 1 neutral side, (2) 6″-7″ interconnecting wires (22 AWG) between each socket in the series; (3) 1 AC receptacle at the end of the set; (4) 1 "return" or neutral line (22 AWG) from the receptacle on the end of the set and then back to the last socket of each circuit in the set until it eventually terminates at the plug; (5) 1 "hot" line (22 AWG) from the plug to the first socket in the first circuit in the set; (6) 1 "hot" line (22 AWG) from the plug to the additional series circuits remaining in the set; (7) plastic light sockets for two wires; (8) plastic light sockets for three wires; (9) two brass electrical terminals per wire; (10) plastic lamp plugs to hold the lamps; and (11) miniature glass lamps.
Another type of prior art light system uses series of small groups of lights in parallel with each other and with a programmable group device. This type of light string is described in U.S. Pat. No. 6,367,952, issued to the present inventor and incorporated herein by reference in its entirety. Each group is in series with each other group. If one or more lights in a group burns out or is removed, the programmable group device is programmed to maintain the current in the remaining lights of the group at levels prior to the burning out or removal of one or more of the lights.
Throughout the world, there are hundreds of millions of strings of holiday lights sold each year. Collectively, they consume significant amounts of energy and produce significant amounts of heat. Even small reductions in the amount of heat and energy consumed by holiday lighting would be a substantial benefit.
Thus, there remains a continuing need for a better string of holiday lights.


In a fuel pump inlet chamber assembly having a communication passage which allows ejection of fuel from the fuel pump inlet chamber to the remaining part of the fuel tank only at a limited flow rate so that any short-term change in the fuel level due to the motion of the fuel inside the tank may not substantially affect the availability of fuel inside the fuel pump inlet chamber, the fuel pump is conveniently interposed in the interface between these two parts, thereby not only simplifying the assembling work but also allowing easy access to the fuel pump for servicing purpose. This takes advantage of the fact that the fuel pump inlet chamber is normally made of molded plastic material, and is required to be constructed from two pieces, i.e., the main body and the lid member. Thus, the fuel pump inlet chamber assembly can be made simple in structure and easy and economical to fabricate while allowing easy access to the fuel pump.

When a vehicle makes a turn with a low fuel level, the resulting lateral acceleration causes a bulk of the fuel in the tank to move to one end of the fuel tank due to its inertia. To prevent the inlet tube of a fuel pump from admitting air, instead of fuel, in such a situation before the fuel level becomes truly low enough, a partly enclosed small chamber is defined inside the fuel tank, and the inlet tube of the fuel pump is placed in this small chamber. Such fuel pump inlet chamber assemblies are disclosed in Japanese patent laid open publication (kokai) No. 2-262428, Japanese utility model laid open publications (kokai) Nos. 2-51932 and 2-78422.
According to such conventional fuel pump inlet chamber assemblies, the fuel pump is normally supported by the fuel inlet chamber assembly. More specifically, the fuel pump inlet chamber assembly is mounted on the bottom wall of the fuel tank via a chamber bracket, and a pump bracket integrally attached to the fuel pump is engaged with a cooperating recess provided in a wall of the fuel pump inlet chamber assembly. However, according to such a pump inlet chamber assembly, the use of a pump bracket adds to the number of the component parts included in the assembly, and increases the cost of the fuel tank assembly due to the increase in the work involved in the assembling process, and the increase in the cost for the component parts.

Fuel pump inlet chamber assembly for a vehicle fuel tank


A children's educational toy includes a log section having a plurality of uniquely shaped and detachable log portions for defining altering portions of the log section. Each log portion has a top surface provided with a plurality of spaced notches for defining a striking area medially of the plurality of log portions respectively. The assembly further includes a wedge, a wood-splitting maul, and a mechanism for locking the plurality of log portions respectively. The locking mechanism includes a plurality of male portions extending outwardly from select ones of the plurality of sidewalls respectively and a plurality of female portions formed within adjacent ones of the plurality of sidewalls. The plurality of male and female portions are removably engageable when the plurality of sidewalls are positioned adjacent the axis.

1.Technical Field
This invention relates to a child's toy and, more particularly, to a toy that simulates the splitting of a log stump and teaches a child mathematic computations.
2. Prior Art
In customary toys for children, so-called block toys or puzzle games are popular. Such toys are characterized by constructions wherein the blocks have fixed shapes. In other block type toys, articles or structures and the like are constructed and constituted by arranging in a row. Block type toys having previously constructed and constituted articles or structures which were designed to be divided by hand have also been developed.
However, upon reaching adulthood, the previous block type toys provided no real log splitting training or experience. A serious situation can arise wherein an adult cannot master the use of an axe or cannot skillfully use other types of chopping utensils because they have no prior experience as a child. In spite of the fact that an edged tool can be a safe article when properly used, the fact that children are usually kept away or are prohibited from using an edged tool because of a preconception that the edged tool is dangerous simply is a cause for this situation. During operation of this toy, a child's physical abilities are enhanced through actions very similar to those utilized by a person actually splitting a log.
Accordingly, a need remains for a toy that simulates the splitting of a log and teaches children how to operate wood splitting tools safely while improving eye-hand coordination.


Filter cartridge that prevents leakage of unfiltered fluid, as well as filter system and method using the same, are provided. The filter system includes a housing having an inlet for introducing unfiltered fluid into the housing and an outlet extending into the housing for draining filtered fluid after filtration occurs. A series of filter cartridges are positioned on the outlet within the housing, and gaskets are placed between adjacent filter cartridges and at each extreme end of the series. Each filter cartridge includes filter material configured in a tubular shape and opposite end walls located at the ends of the filter material. An aperture is formed through each end wall to receive the outlet when the filter cartridge is positioned thereon, and concentric pressure ridges are located on each end wall so as to substantially encompass the aperture. The pressure ridges extend outwardly from the end wall to engage the adjacent gasket and prevent leakage of unfiltered fluid between the end wall and the gasket.

1. Field of the Invention
The present invention relates to a method and apparatus for preventing leakage of unfiltered fluid through a filter system. Particularly, the present invention is directed to a filter cartridge configured to prevent leakage of unfiltered fluid, as well as a filter system and method using the same.
2. Description of Related Art
Fluid and hydraulic systems are commonly used to satisfy a variety of commercial and domestic needs. A common problem shared by such systems, especially closed systems that continuously recycle fluid for reuse, is contamination. Soluble and insoluble contaminants become entrained in the fluid, often building up in system components and adversely impacting overall efficiency. Such contamination results in increased operating and maintenance costs, as well as possible disruption of service when acceptable contamination levels are exceeded. In fact, contamination actually may render some fluid or hydraulic systems useless if untreated, or if the system is sensitive to the presence of contaminants.
To address the problems associated with contamination, a variety of filtration and contaminant removal methods have been developed. One such method uses integral filter units, commonly known as filter cartridges, for the removal of contaminants. A conventional filter cartridge includes filter material held securely between opposite planar end walls. The filter material is configured into a tubular shape having a hollow center extending between the opposite planar end walls, and each planar end wall is provided with a central aperture in alignment with the hollow center. Outer and inner walls likewise extending between and securely connected to the planar end walls also may be provided to encase the filter material.
In operation, one or more filter cartridges are mounted within a filter system. The filter system includes a filter housing that is usually similar in shape to the filter cartridge, but large enough to contain one or more filter cartridges positioned end to end. For example, it is not uncommon for ten (10) or possibly more filter cartridges to be positioned end to end within a single filter housing. An inlet is provided, typically connected to the peripheral wall of the filter housing, for introducing unfiltered fluid into the filter housing. Likewise, a perforated center pipe is provided for supporting and positioning the plurality of filter cartridges within the filter housing, as well as for draining fluid that has passed through the filter cartridges.
The shape and size of the filter housing center pipe corresponds to the apertures provided through the planar end walls of each filter cartridge. Each filter cartridge thus may be mounted within the housing by inserting the center pipe through the apertures. In this manner, unfiltered fluid is introduced into the filter housing by the inlet and directed inwardly through the filter material for filtration before passing through the perforations of center pipe, such that filtered fluid is drained back to the fluid system for reuse.
Gaskets, typically made of felt or other deformable material, are placed on the housing center pipe between the planar ends of adjacent filter cartridges, as well as at each extreme end of the plurality of filter cartridges. The purpose of the felt gaskets is two-fold. First, the gaskets are provided to seal the exposed perforations along the housing center pipe between adjacent filter cartridges. Second, the gaskets are intended to seal the annular gap created proximate the planar ends of each filter cartridge between the apertures and the center pipe of the fluid housing.
Unfortunately, the effectiveness of the gaskets in sealing against leakage is typically limited, particularly once filtration has been initiated. This is because contaminants that collect on the filter material tend to restrict flow through the filter cartridges. If sufficient back pressure develops within the filter housing due to this flow restriction, unfiltered fluid finds a less restrictive flow path between the planar end of a filter cartridge and the adjacent gasket rather than through the filter cartridge itself. Additional factors that attribute to leakage include undetected defects in either the gaskets or the planar ends of the filter cartridges, which prevent full surface contact therebetween, and deflection of the housing center pipe due to the weight of the filter cartridges, thus causing nonuniform pressure on the gaskets by the planar ends of the filter cartridges.
To some extent, it has been determined that the effectiveness of the gaskets may be improved by increasing the compression on the gaskets against the planar ends of the filter cartridges. This may be performed by tightening a threaded nut on the end of the housing center pipe so as to press the filter cartridges and gaskets against each other. It is believed, however, that only little benefit is achieved by this tightening process since the threat of stripping the threaded end of the center pipe or deforming the planar end walls limits the extent of compression available.
In view of the above, there remains a need for a cost effective method and apparatus for preventing leakage of unfiltered fluid through filter systems using filter cartridges.

Filter cartridge having gasket seal employing pressure ridges to prevent leakage


A baking oven for heating lead frames used in the manufacturing of semiconductor devices including an oven main body having an entrance and an exit for lead frames, a heating device which creates a high-temperature atmosphere inside the oven main body, a lead frame magazine installed inside the oven main body so as to accommodate lead frames in a stacked fashion, a magazine mover which moves the lead frame magazine in a vertical direction, and a width adjustment device that changes the width of the lead frame magazine in a horizontal direction. The magazine mover and the width adjustment device are provided outside the oven main body for securing a high lead frame accommodation capacity and a longer heating time of the oven.

1. Field of the Invention
The present invention relates to a lead frame baking oven which is used for the pre-baking (preparatory heating) of insulating tapes applied to lead frames or for the baking (heating) of adhesive agents (resin pastes) applied to lead frames in order to secure semiconductor chips to the lead frames.
2. Prior Art
Semiconductor devices are manufactured, for example, in the following manner: As shown in FIGS. 10 and 12, an insulating tape 2 coated with an adhesive agent is applied in advance to the under surface (FIG. 10(b)) or upper surface (FIG. 12(b)) of the leads la of a lead frame 1, and the lead frame 1 is pre-baked in baking ovens so as to remove moisture from the insulating tape 2. Then, as shown in FIGS. 11 and 13, a semiconductor chip 3 is chip-bonded to the under surface (FIG. 11(b) or upper surface (FIG. 13(b)) of the insulating tape 2, and afterward the electrodes 3a of the semiconductor chip 3 and the leads la of the lead frame 1 are connected via wires 4.
As well known to artisans skilled in the art, there are other type of devices. In this case, the die carrying part of a lead frame is coated with an adhesive agent, a semiconductor chip is pressed against the adhesive agent so that the chip is secured to the lead frame (called "chip bonding"), and then the adhesive agent is baked in baking ovens so that the electrodes of the semiconductor chip are afterwards connected to the leads of the lead frame via wires (called "wire bonding").
Conventional baking ovens used for pre-baking the insulating tapes or for baking the adhesive agent as described above have a straight tunnel type structure. In these types of ovens, a feeder for conveying the lead frames is surrounded by a heat insulating material, and heaters for heating the objects are installed in series beneath the lead frame conveying path, and a cooling device for cooling the lead frames is installed above the conveying path.
Baking ovens of this type are described in, for example, Japanese Patent Application Laid-Open (Kokai) Nos. 55-127025, 55-127030 and 56-87331 and in Japanese Patent Application Publication (Kokoku) No. 3-45539. In particular, the Japanese Patent Application Laid-Open (Kokai) No. 55-127025 relates to a tunnel type oven that supplies into the tunnel with inert gas which is lower in the temperature than the eutectic temperature of solder, the Japanese Patent Application Laid-Open (Kokai) No. 55-127030 relates to an oven provided with a heater inside that is movable horizontally and vertically, the Japanese Patent Application Laid-Open (Kokai) No. 56-87331 relates to an oven with sealing plates that are opened by transferred workpieces and prevent supplied gas from escaping, and the Japanese Patent Application Publication (Kokoku) No. 3-45539 relates to an oven provided with a reducing gas supply and a reducing heater.
In the prior art described above, the straight-line structure oven generally has a small lead frame accommodating capacity. As a result, the pre-baking or baking time is short, and the removal of moisture from the insulating tape or the baking of the adhesive agent is not accomplished unless the temperature of the heater is set high. If, however, the pre-baking or baking temperature is set high, there is a danger that the oven's function halts which results in thermal destruction (or deterioration) of the insulating tape, and there is a danger that such a halt of the oven will lead to thermal destruction of the semiconductor chip. In order to prevent the thermal destruction of the insulating tape or semiconductor chip, the insulating tape or semiconductor chit is protected during the halt of the oven by the cooling device (which effects a cooling blast) by lowering the temperature. However, once the temperature has been lowered, considerable time is required to bring the temperature back to the original set value.
In the meantime, the Japanese Patent Application Publication (Kokoku) No. 4-39227 discloses an apparatus that allows automatic adjustment of the width of the guide rails that guide the lead frames so that the guide rails can comply with changes in the width of the lead frames that occurs when the type of the product to be handled is changed. However, it is difficult to use this guide rail width adjustment means in the conventional baking oven described above. In other words, ovens that can heat any type of lead frames (which differ in size in particular) has not yet been practically used.


The invention concerns a device for processing signals in the form of successive packets sent in successive time slots of the type comprising a processing system including at least one processing member with secondary effects (81, 82) likely to generate disturbances affecting adjacent packets. Two processor members (81, 82) with secondary effects are disposed in separate channels (90, 91) and switching means (83, 84) cyclically connect the separate channels each during one time slot and disconnect them between times so that a channel connected to process a packet cannot be disturbed by adjacent packets each processed by another channel.

The invention concerns devices for processing signals in the form of packets and in particular devices of this kind using a processor member having secondary effects likely to generate disturbances affecting adjacent packets.
Devices of this kind are used in time-division multiple access (TDMA) system receivers, for example. The TDMA technique is used in the GSM digital cellular radiotelephone system, for example. In a system of this kind mobile stations communicate by radio with fixed base stations which are connected into the conventional telecommunication network. Communication between a fixed station and mobile stations within its coverage area uses a two-way frequency channel which is time-shared between a plurality of mobile stations, one time slot in a repetitive frame being assigned to each mobile station. The combination of the time slots of these repetitive frames assigned to a given mobile station in this way is sometimes called a channel time slot. In the mobile station to fixed station direction each mobile station sends a data packet in each time slot assigned to it and at its own level. When received at the fixed station the packets from the various mobile stations, which follow on in sequence in the time slots of each frame, do not all have the same amplitude. Because of varying propagation conditions (different distances, obstacles, etc.) their amplitudes are distributed over a broad dynamic range. These differences in level must be compensated at the input of the fixed station receiver.
A solution proposed by the applicant in French patent application n.degree. 92.03754 filed the same day as this application under the title "Dispositif de commande de gain dans un recepteur de signaux d'information" ("Gain control device in a data signal receiver") uses variable gain amplifier means, evaluator means to receive the input signal and to derive from it an amplitude signal, processor means coupled to the evaluator means, receiving the amplitude signal and deriving from it a gain control signal which is passed to a gain control input of the amplifier means, and a delay line between the signal input and the amplifier means supplying to the latter a delayed input signal such that the gain control signal is available to control the gain in the amplifier means when the latter receive the delayed input signal.
The gain control device in this solution further comprises a filter, for example a band-pass filter, to filter the input signal.
The delay line and the filter just mentioned are two examples of processor members having secondary effects likely to generate disturbances affecting adjacent packets.
There is some unwanted coupling between the input and the output of a delay line. If the delay line conveys consecutive packets, as in the system described, the start of one packet may disturb the end of the previous packet.
A passive analog delay line has another unwanted effect, namely the multiple routing of a signal by reflection of the signal at the output, backwards propagation through the line, reflection at the input and further forward propagation to the output which thus supplies not only the input signal delayed once by the line but also an attenuated replica delayed three times by the line. This may disturb the start of the next packet.
A narrowband analog filter such as a quartz crystal filter is itself subject to a ringing phenomenon which extends the length of a packet and may disturb the start of the next packet.
These unwanted secondary effects can naturally be reduced to the point where they are acceptable, but this entails costly precautions.
Also, the situation just referred to of reception of signals in TDMA systems like the GSM system is merely one example and the man skilled in the art will be aware of many other situations of processing signals in the form of consecutive packets where the same problem arises.

Device for processing signals in the form of packets


A computing device is provided configured to compute a data function on a function-input value comprising an electronic storage storing a table network configured for the data function and an electronic processor coupled to the storage and configured to compute the data function by applying the table network, wherein the device is configured to obtain the function-input value as an encoded input value, the encoded input value combines the function-input value together with a state-input value encrypted together into a single value, the table network is configured to take as input the encoded input value and produce as output an encoded output value, the encoded output value combines a function-output value together with a state-output value encrypted data function together into a single value, wherein the function-output value equals the result of applying the data function to the function-input value, and the state-output value equals the result of applying a state function to the state-input value.

US 2012/0300922 discloses a method for generating a correspondence table suitable for use in a cryptographic processing method and comprising storing a plurality of input data and of output data in the table, each input datum being associated with at least one output datum in the table. For each input datum, at least one of the output data is obtained by applying a coding function to a first subsidiary datum and to an encrypted intermediate datum depending on the input datum.
US 2012/0155638 discloses that in the field of computer enabled cryptography, such as a block cipher, the cipher is hardened against an attack by protecting the cipher key, by applying to it a predetermined linear permutation before using one key to encrypt or decrypt a message. This is especially advantageous in a "White Box" environment where an attacker has full access to the cipher algorithm, including the algorithm's internal state during its execution. This method and the associated computing apparatus are useful where the key is derived through a process and so is unknown when the software code embodying the cipher is compiled. This is typically the case where there are many users of the cipher and each has his own key, or where each user session has its own key.
In traditional cryptography it was typically assumed that an attacker only gains access to the input and output values of a secure system. For example, the attacker would be able to observe a plain text going into a system and observe an encrypted text going out of the system. Although an attacker could try to gain an advantage by analyzing such input/output pairs, possibly even using computationally intense methods, he was not thought to have direct access to the system that implemented the input/output behavior.
Recently, it has become necessary to take threat models into account in which it is assumed that an attacker has some knowledge of the implementations. For example, one may consider the threat of side-channel analysis and of reverse engineering. Furthermore, the concerns that previously were mostly associated with security problems have extended to other fields, such as privacy. Although cryptographic systems processing security information such as cryptographic keys remain a prime concern, protection of other programs, e.g., those processing privacy relevant information has also become important.
It has long been known that computer systems leak some information through so-called side-channels. Observing the input-output behavior of a computer system may not provide any useful information on sensitive information, such as secret keys used by the computer system. But a computer system has other channels that may be observed, e.g., its power consumption or electromagnetic radiation; these channels are referred to as side-channels. For example, small variations in the power consumed by different instructions and variations in power consumed while executing instructions may be measured. The measured variation may be correlated to sensitive information, such as cryptographic keys. This additional information on secret information, beyond the observable and intended input-output behavior is termed a side-channel. Through a side-channel a computer system may 'leak' secret information during its use. Observing and analyzing a side-channel may give an attacker access to better information than may be obtained from cryptanalysis of input-output behavior only. One known type of side-channel attack is the so-called differential power analysis (DPA).
Current approaches to the side-channel problem introduce randomness in the computation. For example, in between real operations that execute the program dummy instructions may be inserted to blur the relationship between power consumption and the data the program is working on.
An even stronger attack on a computer is so called reverse engineering. In many security scenarios attackers may have full access to the computer. This gives them the opportunity to disassemble the program and obtain any information about the computer and program. Given enough effort any key hidden say in a program may be found by an attacker.
Protecting against this attack scenario has proven very difficult. One type of counter measure is so-called white-box cryptography. In white-box cryptography, the key and algorithm are combined. The resulting algorithm only works for one particular key. Next the algorithm may be implemented as a so-called, lookup table network. Computations are transformed into a series of lookups in key-dependent tables. See for example, "White-Box Cryptography and an AES Implementation", by S. Chow, P. Eisen, H. Johnson, P. C. van Oorschot, for an example of this approach.

Computing device comprising a table network

Paulus Mathias Hubertus Mechtildis Antonius


A cursor query identifier is defined to uniquely identify cursors in a relational database system that supports nested routine invocation. The identifier includes a cursor nesting level value that corresponds to the nested level at which the cursor is opened. The identifier also includes a invocation identifier that corresponds to the routine within which a cursor is opened. The third part of the identifier is a unique cursor counter. The definition of the cursor query identifier permits cursors to be opened within nested levels of the same relational database context and to be uniquely identified for reference by database system and by applications accessing the system.

In relational database management systems (RDBMSs) implementing a query language such as SQL (Structured Query Language), it is known to support application defined cursors. A cursor is identified relative to a query result set in a relational database and is used to access the result set in a controlled row by row manner.
A database system may support user-defined routines such as stored procedures or user defined functions (STPs or UDFs). In a stored procedure, it is possible to include statements to open a cursor, fetch data and then have the procedure execution return to the application, leaving the cursor open. The application may be defined to fetch data using the cursor opened by the stored procedure. If the application again invokes the same stored procedure, then a second occurrence of the same cursor can potentially take place. However, when the stored procedure in this example attempts to open the cursor in the second invocation, the RDBMS may return an error: the system will interpret the second open request as an attempt to open an already open cursor.
This type of problem may potentially also occur where procedures or functions are able to invoke other procedures or functions or where a single function is potentially accessible by many different processing branches of an application at the same time. Where routines are executed in parallel by the same application, the attempt to open multiple cursors with the same name in those routines may cause errors in a database system.
Unless cursor identification is uniformly maintained both at the user or client layer and at the server layer, the above problems may occur at either the client side or the server side of a relational database system. The location where an error is declared will depend on where the database system resolves identification issues for cursor requests. Although database systems will typically treat the multiple opening of cursors with the same name as an error condition, as can be seen from the above, there are many cases where it is desirable to permit cursors with the same name to be opened.

Unique identification of SQL cursor occurrences in a repetitive, nested environment

International Business Machines Corporation


A computer mainframe housing including a rectangular metal base frame, a front panel and two rectangular cover panels and at least one square cover panels respectively covered on the base frame, wherein each of two opposite rectangular sides of the base frame has two rows of lugs longitudinally and bilaterally disposed along the border, a retaining hole near one end, rows of hooks longitudinally disposed between the rows of lugs, and one row of sliding slots longitudinally disposed between one row of lugs and the rows of hooks; each rectangular cover panel has a front flange forced into engagement with the front panel, longitudinally grooved reinforcing ribs at an inner side, a plurality of crossed tenons respectively disposed in the longitudinally grooved reinforcing ribs and forced into the sliding slots of one rectangular side of the base frame, a rear finger strip, a hook raised from the rear finger strip and forced into engagement with one retaining hole of the base frame; each square cover panel has two rows of inward hooks respectively forced into engagement with the lugs of the base frame, a finger strip, and a hook raised from the finger strip and forced into engagement with a respective retaining hole on the base frame.

A personal computer generally comprises a PC board, a power supply unit, a cooling fan, a floppy diskdrive, a hard diskdrive, a speaker, and a plurality of card guides. For supporting these parts inside the personal computer, a metal frame is commonly used and then covered with a cover shell. This metal frame has holes and lugs for mounting. The housing of the personal computer is generally comprised of a substantially U-shaped cover shell covered on the metal frame, and a front panel secured to the cover shell. This U-shaped cover shell can be injection-molded from plastics or made from metal by stamping, however it cannot be used for both the horizontal computer and the vertical computer. Therefore, different cover shells shall be used for different types of computers. If the cover shell of a personal computer is injection-molded from plastics, the molding cost is expensive. If the cover shell of a personal computer is made from metal by stamping, it can only have a paint-coated smooth outer surface, which does not attract consumers. Furthermore, if a metal cover shell is used, many screws shall be used to fix it to the metal frame. This complicated installation procedure greatly consumes much labor. Nowadays, plastic housings are commonly used for personal computers. These plastic housings are commonly comprised of a plurality of panels assembled together. However, because these panels are fastened together by screws, the assembly process still consumes much labor.

Mainframe housing of a personal computer


An assembleable lighting system is provided which may include a power transfer means connected to a fixture mounting pendant or pole. At least one node of power input to the power transfer means is provided. Mounted to the power transfer means is a fixed or adjustable mounting bar or beam construction. A retaining ring is adjustably movable along the mounting bar or beam member. One or more of said retaining rings, mounted to the mounting bar, are able to retain accessories for the lighting system. A low voltage transformer means is provided which is easily mountable to the beam member when it is necessary to convert the lighting system to a low voltage application.

1. Field of the Invention
The present invention relates to lighting systems. More particularly, the invention relates to spot light type lighting systems of the type which illuminate stage plays, live performances, retail display areas and the like.
2. Description of the Prior Art
The problem of how to provide a useful lighting system which is versatile enough to perform all the functions needed of a spot light, and yet not be unduly cumbersome or inconvenient to use, is one of longstanding in the prior art. Such a lighting system has many requirements depending on the use to which it is put. If, for example, such a lighting system is being used in an outdoor amphitheater, the requirement of most importance would be the ability to deliver a large amount of light in various colors, and to focus such light precisely. The size or ease of adjustability of such lights are usually not of concern.
If, however, such lights are used to illuminate indoor stages or retail display areas, the requirements become quite different. It may be required, for example, to use a low voltage bulb instead of one working off line voltage, and to adjust the light fixture, including the focusing features, from a remote location.
In addition, in either situation, many parts are needed, such as template projectors, bellows, barn doors, color filters and focusing lenses. It is a common complaint among lighting technicians that so many parts are required that they frequently get lost, and it is easier to replace them rather than find them. This leads to an unnecessary waste of scarce resources. Therefore, those skilled in the art have continued to search for an easily adjustable lighting system which can be changed between line voltage and low voltage, and which has a self storing feature.


A sleeve or collar for preventing the migration of infection along the length of an implanted lead. The sleeve or collar is given anti-microbial properties, as by embedding therein or coating with anti-microbial substance. At the time that a changeable portion of an implantable device is changed-out, e.g., when the pulse generator in a pacemaker system must be replaced due to battery depletion, the collar or sleeve in accordance with the present invention is affixed to the lead and slid as far distal along the lead as possible, in order to ensure that a barrier is established to prevent the migration of infection to the extreme distal end of the lead. In one embodiment of the invention, the collar or sleeve can serve the dual purposes of establishing an infection barrier and of facilitating the anchoring of the lead in place.

A variety of different types of therapeutic and/or diagnostic implantable medical devices, including implantable pacemakers, cardioverters, defibrillators, neural stimulators, and the like, have been shown in the prior art. Often, such implantable medical devices employ an hermetically-sealed electronic component, such as a pulse generator and/or a sensing circuit, in conjunction with one or more flexible, implantable, electrically conductive leads. For example, pacing and sensing leads are used in pacemaker systems to convey electrical stimulating pulses from an implanted pulse generator to the patient's heart, and to convey electrical cardiac signals from the heart to implanted sensing circuitry associated with the pulse generator.
In systems employing an implantable lead, lead infection resulting from the introduction of bacteria at the implant site at the time of implant is a rare but serious complication. In the prior art, it has been suggested to coat the lead with anti-microbial substances in order to reduce the risk of infection. However, the more common and much more serious--possibly life-threatening--complication is the possibility of infection at the time when an implanted component is replaced or "changed out", i.e., when an old implanted component (such as the pulse generator in a pacemaker system) is removed and a new component is implanted in its place. Changing out the implanted electronic component of a medical device may be required, for example, when its battery becomes depleted, or when it malfunctions.
Frequently, when the electronic component of a medical device is changed-out, it is not necessary or desirable to also remove and replace the implanted lead(s) with which it is used. Lead implantation can be a complicated procedure, and unless a lead has become worn or damaged, or has become dislodged from the proper positioning, it is usually preferable upon pulse generator change-out to merely disconnect the electronic component from the implanted lead(s), leaving the lead(s) in place for subsequent reconnection to the replacement component.
In the of a typical pacemaker, battery depletion requiring pulse generator change-out may occur five to ten years after initial implant. During this five to ten years, an implanted lead will typically become encapsulated in fibrous tissue, which is a further reason for leaving the lead in place for pulse generator change-out.
Resident inflammatory cells in the fibrous tissue surrounding an implanted pulse generator and lead become weakened or "exhausted" over time, such that at the time of pulse generator change-out, the amount of bacteria which can cause infection at the implant is reduced by several orders of magnitude. Once the implant pocket becomes infected, the infection can migrate along the lead sheath to the heart. Given the exhausted inflammatory system locally, such a migrating infection can become intractable and life-threatening. Removal of the pulse generator and lead is then necessary to cure the infection. However, as noted above, removal of a chronically implanted lead can be difficult and dangerous, and in some cases could require a thoracotomy.
In view of the foregoing, it is believed that it would be desirable to provide a means to prevent the chronic migration of infections along the length of an implanted lead.


A torsional vibration damping device located between an input member and an output member of a power transmission device comprises a case and a slider. The case is connected to either the input or output member, extends circumferentially and contains fluid. The slider is connected to the other input or output member and is located within the case at a given clearance from an inner wall thereof wherein It is slidable circumferentially. The coefficient of thermal expansion of the slider is greater than that of the case.

The present invention relates to a torsional vibration damping device and a lock-up clutch in a torque converter comprising three kinds of vane wheels (impeller, turbine and stator) wherein torque is transmitted by means of hydraulic fluid. The impeller is fixed to a-front cover connected to an input rotation member, and the turbine is rotated by the hydraulic fluid flowing from the impeller.
Some torque converters include a lock-up clutch between the turbine and the front cover. The lock-up clutch transmits torque from the front cover to an output member directly. The lock-up clutch includes elastic members such as torsion springs in order to absorb torsional vibrations. It is preferable that the torsional springs have low rigidity so as to prevent noise at the idling or driving of a vehicle. Low-rigidity torsion springs are, however, a cause of large vibration of the vehicle in the front-to-rear direction when low frequency vibration is generated by acceleration or deceleration during the lock-up engagement.
In order to solve the above mentioned problem, Japanese Utility Model Laying-Open document No. 123258/1986 shows a viscous damping mechanism and an elastic connection device which function in parallel. The-torsional vibration damping device mainly comprises a first cylinder provided on the input rotation member, and a second cylinder connected to an output member, wherein an annular fluid chamber is formed between them. The first cylinder and second cylinder are provided with partition plates alternately extending toward each other, wherein a clearance is defined between the ends of the partition plates and the cylinder end surface opposite. When both cylinders are made to twist relative to each other by torsional vibration, the fluid flows through the clearance giving rise to viscous damping.
In the above described structure, accuracy of the clearances is low. That is, when both cylinders are fixed to the input member and the output member respectively, the clearances become different because of working errors and assembly errors. Moreover, when the temperature of the fluid rises due to viscous friction, the fluid viscosity becomes low such that the viscous damping decreases and desired damping effects cannot be obtained.

Torsional vibration damping device and lock-up clutch in torque converter


Systems and methods for managing a network are disclosed. One method can comprise determining a first modulation rate associated with a network device. A beacon can be transmitted at a second modulation rate, wherein the second modulation rate is greater than the first modulation rate. A user device can be associated with the network device based on the beacon if the user device is configured to support the second modulation rate.

A network such as a local area network can comprise one or more network devices (e.g., access point (AP)) to provide a means for one or more user devices to communicate with and/or over the network. A network device can comprise a device that allows wired and/or wireless user devices to connect to a wired network using Wi-Fi, Bluetooth, or related standards. A network device can be configured to provide access to one or more services (e.g., private network, public network, network-related services). In certain Wi-Fi networks the AP can transmit a beacon. A user device can listen for this beacon to discover the AP availability in the local area. However, issues can arise when the user device discovers the presence of a WiFi network based on a perceived beacon strength, but the user device is unable to successfully connect and sustain a quality connection. For example, when the AP has a more powerful transmit power than the user device, this causes an asymmetric received signal strength indicator (RSSI) problem where the user device can receive and process the signal from the AP but the AP cannot receive and process the signal from the user device. Another problem is that the beacon is sent by the AP at the lowest configured rate at which the AP can transmit. Accordingly, improvements are needed for provisioning and managing devices connected to a network. These and other shortcomings are addressed by the present disclosure.


To apply indicia to a surface of a traveling workpiece, particularly of a rapidly moving workpiece, a beam of coherent laser light is split to form two rays, one of which is deflected directly onto the surface whereas the other is indirectly guided onto the surface. The two rays form on the surface two parallel indicia which are located opposite one another but are spaced transversely of the direction of workpiece movement.

This invention relates to the application of indicia to workpieces.
More particularly, the invention relates to the application of indicia to a surface of a moving workpiece.
Still more specifically, the invention relates to a method of and an apparatus for applying indicia to a surface of a moving workpiece.
Many types of moving workpieces must be provided with indicia which may be indicative of workpiece batch numbers, workpiece quality or the like. The invention will hereafter be described with respect to the application of indicia to a surface of a moving workpiece, particularly a rapidly moving workpiece such as a metal plate or a metal tape (e.g. a steel plate or steel tape), although it should be understood that the invention is by no means limited to this application.
It has been proposed in Ser. No. 910,277 to subdivide the surface of a workpiece (e.g. a plate or a tape) intermediate an inspection station and an indicia-applying station into zones having a length corresponding to the length of the indicia to be applied, whereupon each individual zone is electronically tracked intermediate the inspection station and the indicia-applying station, and the surface of each of the thus-tracked zones is oxidized and melted by the application of a laser beam from a laser light source. Each of the zones to be tracked is assigned a space in a shift register associated with the inspection station, and according to a preferred embodiment of this prior proposal the items of information from the individual shift registers are supplied to the laser light source simultaneously or sequentially to control the operation of the same, and simultaneously or in timed succession converted into laser-light pulses.
This prior proposal has been found to be highly advantageous in many applications. However, there are certain applications in which a more precise marking of e.g. faults in the tape or plate is necessary or at least desirable. For such applications, a further improvement is necessary.

Method of and arrangement for applying indicia to a surface of a moving workpiece


A composition which is an anhydrous organic solvent free mixture of a hydrolyzable silane monomer; silanols formed by hydrolysis of the silane monomer; alkoxy functional oligomers formed by condensation of the silanols such as dimers and trimers; and higher alkoxy functional oligomers such as tetramers. Methods of making and using the composition are described.

This invention relates to a composition and to a method of preparing a composition useful in the treatment of porous surfaces such as masonry. More particularly, the composition contains a hydrolyzable silane monomer, silanols, and alkoxy functional oligomers, and the composition is anhydrous and essentially organic solvent free.
The advent of Federal and State regulations directed to environmental concerns particularly in the area of architectural coatings has created the need for solventless compositions. Solvent free architectural coatings containing silanes are known in the art as evidenced by U.S. Pat. No. 4,716,051 issued Dec. 29, 1987. In the '051 patent, one hundred percent of a pure solvent free alkyltrialkoxysilane is applied to the surface of concrete to render the surface hydrophobic. The present invention is an improvement over this technology, and provides a treating composition which is anhydrous as well as being solventless or free of organic solvent, while at the same time including in addition to a silane monomer, silanols and alkoxy functional oligomers thereof. The prehydrolyzed composition of the present invention will generate less organic alcohol liberated during further hydrolysis of alkoxy groups upon contact with moisture, thereby rending the composition of the present invention more environmentally acceptable. Since the compositions are anhydrous, stability problems during storage of the composition prior to its use caused by decomposition in aqueous medium are reduced. Thus, the compositions will remain stable for a sufficient time to make it economically feasible to employ these materials in coating applications.


A container for marking instruments comprises a support strip having a plurality of pockets attached to a carrier so as to interact with other pockets on another support strip for the purpose of securing the marking instruments neatly in place when not in use.

The present invention relates in general to containers for marking instruments and more particularly to containers adapted to be assembled in a binder or between covers.
Usually a plurality of crayons, pencils, artists' paintbrushes and the like are deposited together in a container such as a simple box. It is sometimes desirable to arrange the container so that the marking devices can be kept separate and neatly in place in an organized manner, such as by size or color. It is also desirable to arrange the container so that it might serve another purpose other than holding the markers.
Accordingly, it is an important object of this invention to provide an improved container or holder for marking instruments.
It is a further object of the invention to achieve the preceeding object with a holder that may be detachably secured to a binder.

Containing markers in interleaved relationship

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