An energy conversion generation system receives energy from a resource and converts the energy into electrical power for supply to a polyphase electric power grid operating at a system frequency. A prime mover driven by the resource energy and a converter, such as a power electronic converter, for produces excitation power from power received from a converter power source. A brushless doubly-fed generator has a rotor with rotor windings and a stator with stator windings comprising first and second polyphase stator systems. The rotor is driven by the prime mover. The first stator system supplies the electrical power to the grid, and the second stator system receives the excitation power from the converter. A sensor senses a parameter of the electrical power output supplied to the grid and produces a sensor signal corresponding to the sensed parameter. A controller controls the converter in response to the sensor signal. The controller establi. This invention was made with government support under Grant No. 79-85BP24332, awarded by the Bonneville Power Administration. The United States government has certain rights in this invention.

This invention relates generally to energy conversion systems for generating electricity and to methods of controlling such systems, and more particularly to a variable speed generation (VSG) system and control method utilizing a brushless doubly-fed generator which operates in both an induction mode and a synchronous mode. Such a brushless doubly-fed machine has a winding structure different than four other known types of electrical machines.
First, a synchronous machine typically has one set of polyphase power windings on a stator which are connected to a grid. The synchronous machine has DC (direct current) field or excitation rotor windings terminating at slip rings on the rotor. Via the slip rings, the excitation windings are connected by brushes to an external DC excitation source. Such brushes require periodic maintenance and replacement, which typically requires that the synchronous machine be disconnected from the power grid and the rotor brought to essentially a standstill. The brushes and slip rings also increase the electrical losses of the machine which detracts from the overall machine efficiency.
A synchronous machine is restricted to operation at a particular synchronous speed, and if torque requirements are exceeded the machine will lose synchronism, commonly referred to as "slipping a pole." Thus, a synchronous generator is not well suited to variations in the resource energy received from an inherently variable resource, such as hydro or wind.
Secondly, an induction machine also has polyphase power windings on a stator which are connected to a grid. The induction rotor may be either a wound rotor having rotor windings or a squirrel cage rotor having conducting bars embedded in slots on the rotor and interconnected at each end by conducting rings. An induced polyphase current circulates through the wound rotor windings or the squirrel cage rotor bars.
An induction generator suffers from several major limitations, including an inflexible nature concerning speed variation. Speed control by varying the rotor resistance is inefficient. Speed control by varying the stator voltage and/or the stator frequency requires a power electronic converter having the same rating as the generator, placed between the stator terminals and the electric power grid. Thus, such a power electronic converter carries the full load current, which increases the operating costs due to power losses within the converter, as well as the initial cost of purchasing the system. Moreover, an induction generator requires a reactive power input. Thus, additional equipment is required, such as a static VAR system, which further increases the initial and operating costs. As a further disadvantage, the induction generator is inherently incapable of generating a reactive power output.
Thirdly, a hybrid electrical machine is a doubly-fed generator with brushes which has a stator with polyphase power stator windings connected to a grid. The hybrid doubly-fed machine has a wound rotor with polyphase excitation rotor windings terminating at slip rings. Via the slip rings, the rotor windings are connected by brushes to an external energy converter. This varies from the synchronous and induction machines discussed above, in that the energy converter varies the amplitude and frequency of AC rotor current or voltage to control the rotor speed and the output characteristics of doubly-fed machine. A controller monitors various system inputs and outputs, and according to a desired control strategy provides amplitude and frequency control signals to the energy converter. Such a doubly-fed generator is described in a pending United States application, of which the inventor of the present application is one of the coinventors, entitled "Doubly-fed Generator Variable Speed Generation Control System", Ser. No. 07/304,044.
However, this hybrid doubly-fed machine requires brushes to transfer the excitation power from the energy converter to the polyphase rotor windings. The same disadvantages of brushes used on synchronous machines are also present in the hybrid doubly-fed machine, namely: maintenance and replacement costs including parts, labor and machine down-time; and decreased efficiency from the additional electrical loses imposed by the brushes and the brush/slip ring interface.
Finally, a cascade induction motor for low speed operation was developed in the late 1800's. The original cascade machine was a two-frame machine comprising two wound rotor induction motors mechanically coupled together and coupled to the load. The primary motor slip power, that is the power extracted from the rotor windings of the primary machine, excites either the secondary machine stator windings or the rotor windings via slip rings and brushes. When the rotor of the secondary machine is excited, external resistances are added to the stator windings to control the speed. A rectifier-invertor returns the excess slip frequency power to the grid. By adjusting the invertor firing angle, the effective voltage and slip as seen from the secondary machine stator terminals is varied.
Brushless machines having two sets of polyphase stator systems with separate or shared common stator windings, and a squirrel cage rotor, have been studied and proposed by others in the past, particularly in the motor context. However, the extent of these studies has been to the use of the machine in a singly fed mode, that is, an induction mode. Any attempts at synchronous operation were limited to a single synchronous speed.
These prior studies and papers, discussed further below, are vague on the design aspects of the brushless machine, especially concerning the pole pitch of the windings. Generally, these machines had one set of stator windings connected to a power grid, and the other set of stator windings connected to a bank of variable resistors which were used to control the machine speed. The electrical losses produced by these resistors resulted in a very inefficient machine. Additionally, the use of the brushless machine in a singly fed or induction mode resulted in a poor power factor.
Power factor refers to the relative phases in the time domain of the waveforms of the polyphase AC voltage and current. For example, unity power factor is achieved when the waveforms of the polyphase AC voltage and current are in phase, that is, neither waveform is leading or lagging the other waveform. Operation at a poor power factor, such as a lagging or inductive power factor wherein the current waveform is lagging in time behind the voltage waveform, results in greater electrical losses within the machine, as well as on the lines feeding the machine, which detract from the overall machine efficiency.
The first discussion of which the inventor is aware of a brushless machine having two sets of three phase stator systems with common windings appears in a 1907 article by Hunt. (J. L. Hunt, "A New Type of Induction Motor," Proceedings of the IEE, Vol. 39, pp. 648-667, 1907.) A new induction motor was proposed by Hunt to overcome the limitations of prior single frame cascade induction motor designs.
The motor described by Hunt has a stator with a single stator winding having terminals for connection to a grid. The stator windings are grouped in parallel circuits and have taps, but are otherwise of the ordinary type. The parallel circuits are shared by each of the two three phase systems. The taps are connected in pairs through resistances during starting or during rheostatic speed control, and the taps are short-circuited at normal speed. This varies from the start-up control of the torque and speed of a conventional slip ring motor wherein the resistances are connected to the rotor windings by the slip rings, and not to the stator windings.
The rotor of the Hunt motor has a short-circuited winding comprising shorted rotor bars. This provides a rotor which is mechanically simple and approximates the construction of a squirrel cage rotor which is commonly used in induction motors. If the rotor has no slip rings, that is, a brushless rotor, the motor runs at one efficient speed. The Hunt motor may operate at two, three or four efficient speeds by using slip rings and varying the number of rotor poles with an external switching means. Thus, the Hunt motor does not operate at any desired speed, but only at a few fixed speeds.
The Hunt article also discloses that if continuous or DC current is supplied to one set of stator windings and AC current to the other set, the motor will run at one single synchronous speed like a conventional synchronous motor. In this case, the machine is started from a standstill as an induction motor until normal speed is reached. At this point, the DC current is applied to one set of stator windings by closing a switch, and the motor pulls into step for operation at synchronous speed. The Hunt motor does not operate at variable speeds while operating in a synchronous mode.
In a 1921 article by Creedy, additional developments in multi-speed cascade induction motors were examined, including faster motors, and those having a greater number of discrete stepped speeds with smaller intervals between them. (F. Creedy, "Some Developments in Multi-Speed Cascade Induction Motors," Proceedings of the IEE, Vol. 59, pp. 511-532, 1921.) In a conventional manner, intermediate speeds between the discrete steps are obtained by adding resistance to the rotor windings across the slip rings. Such resistances, of course, detract from the overall machine efficiency by nonproductively consuming power and dissipating it as heat (I.sup.2 R losses).
Basically, Creedy proposed a design method which removed some of the limitations of the Hunt design method. Creedy proposed two systems of stator windings, one having two poles and the other having six poles. In the discussion after the article, Hunt approves of the Creedy method and proposes using the two plus six pole stator winding configuration of Creedy with a brushless ("without slip-rings") rotor to obtain a commercial motor which runs at 750 rpm.
In a 1970 paper by Broadway and Burbridge, the rotor design of the Hunt induction motor was improved upon by producing a more efficient, robust, and economical squirrel-cage rotor. (A.R.W. Broadway and L. Burbridge, "Self-Cascaded Machine: A Low-Speed Motor or High-Frequency Brushless Alternator," Proceedings of the IEE, Vol. 117, No. 7, pp. 1277-1290, July, 1970.) The Broadway/Burbridge machine is a self-cascaded single-frame unit which operates in a manner equivalent to a two-machine arrangement, where one machine would have two p-poles, and the other machine, two q-poles. The fields of each machine share a common magnetic circuit and the currents, which are normally separate, share the same windings. Each phase of the stator winding carries two component currents, each generally of a different frequency and flowing in different paths within the same winding. However, each phase winding in the rotor carries a single current of only one frequency.
The Broadway/Burbridge machine may run asynchronously using resistance control, or synchronously without external rotor winding connections; that is, without slip rings or rotating diodes. For synchronous operation, the two q-pole components of the single-stator winding are energized with direct current. Broadway and Burbridge refer to this as being "doubly-fed," where a single stator winding receives both alternating (AC) current and direct (DC) current. The authors emphasize that "it is clearly desirable that no alternating current should flow in the direct-current supply, and vice versa." Thus, Broadway and Burbridge's use of the term, "doubly-fed" is quite different from that used herein to describe a preferred embodiment of the subject invention.
The Broadway/Burbridge rotor is a multicircuit single-layer winding with each slot containing only one conductor. A single rotor winding may be formed by a U-shaped conductor occupying two slots, with the ends of the U-shaped conductor shortcircuited by a squirrel-cage end ring. Several such U-shaped windings of increasing size may be grouped concentrically in adjacent rotor slots. For example, the innermost U-shaped winding may have one slot between the legs of the U-shaped coil, and this central slot may be left unoccupied. Thus, the Broadway/Burbridge rotor is simple to construct and highly durable or robust.
To avoid an unbalanced magnetic pull which occurs when two fields differ by only two poles, Broadway and Burbridge state that it is "essential" that the two main fields differ by a minimum of four poles. The highest speed operation of this machine as a motor, and the lowest frequency output as an alternator, exist when the two fields are of six poles and two poles. For example, four such groups of concentric U-shaped windings may be used for a (6+2)-pole rotor winding.
In a 1978 article, Kusko and Somuah proposed speed control of a self-cascade single-frame brushless induction motor using a frequency converter comprising a DC-linked rectifier-invertor. (A. Kusko and C. B. Somuah, "Speed Control of a Single-Frame Cascade Induction Motor with Slip-Power Pump Back," IEEE Transactions on Industrial Applications, Vol. IA-14, No. 2, pp. 97-105, 1978.) The frequency converter provides slip recovery or slip-power pump back; that is, excess power not required at a particular speed is fed back into the grid which supplies power to the motor. This motor comprises two wound-rotor induction motors which are built on a common set of core laminations within a single motor frame. The rotor windings of these two motors are interconnected on the single rotor to form a self-cascade system. The rotor has no slip rings or brushes and each rotor winding is described as consisting of one squirrel-cage bar and two short-circuited single conductor coils.
The stator has two sets of stator windings. The primary stator winding has the greater number of poles, for example four, and is connected to the grid. The secondary stator winding has the lesser number of poles, such as two, and is connected to the solid-state rectifier-invertor. The synchronous speed of the motor is set by the sum of the pole pairs of the primary and secondary stator windings. Thus, synchronous operation occurs at a single synchronous speed.
The Kusko/Somuah motor achieves a speed variation by removing the excess power from the stator through the secondary windings and applying it to the rectifier-invertor of the frequency converter. The power as received by the rectifier- invertor is AC and appears in a variety of frequencies. The rectifier portion of the frequency converter rectifies this wild frequency AC power into DC power which travels through a DC link to the invertor. The invertor portion then converts the DC power into AC power at the grid frequency for supply back into the power grid. Thus, there is no real control of the motor, just a recovery of the surplus power not required by the motor. According to the authors, the maximum benefit of the slip-energy recovery system is only attained at low speeds.
Kusko/Somuah state that operation of their device as a generator is impossible due to the unidirectional properties of the bridge rectifier diodes. However, if this limitation were overcome, operation as a generator occurs above a certain maximum speed only if there is a power reversal from the invertor to the rectifier in the DC link. That is, output power flows out of the primary (four-pole) stator winding and into the grid. This output power is equal to the total slip-frequency power flow into the secondary (two-pole) stator winding plus the mechanical power received from the turbine less the electrical and mechanical losses.
The Kusko/Somuah motor suffers from several limitations which would apparently limit a generator of the Kusko/Somuah design. For example, the frequency converter must be sized to handle the slip power which is proportional to the maximum slip times the load torque. Such a large frequency converter increases the cost of the overall system. Only the wide-speed range drives are capable of being started with the frequency converter. However, these wide-speed range drives suffer from a reduced power factor at part speed.
The Kusko/Somuah motor is unsuitable for driving varying mechanical loads. From an examination of the equations given by the authors, it is apparent that if the mechanical load driven by the motor varies, the speed of the motor will also vary. That is, such load variations will cause a shift in the torque-speed characteristic of the motor. Correction of this torque-speed characteristic requires injecting a voltage. That is, the voltage is injected at the second set of stator three phase systems. Therefore, control of the Kusko/Somuah motor also requires a speed control feedback loop, which monitors the shaft speed and supplies firing control to the frequency converter. Finally, the slip power control method not only requires reactive power for the converter, but also renders it impossible for the generator to generate reactive power. This is essentially because this method operates the machine in a singly-fed mode, i.e. the machine behaves like a conventional induction machine.
Thus, a need exists for a new VSG system, controller and method of controlling such a system to exploit the attractive features of a brushless doubly-fed generator, and to provide electrical power at a maximum efficiency from an energy source, such as the variable alternative energy resources of hydro and wind.

Brushless doubly-fed generator control system

The State of Oregon acting by and through the State Board of Higher Education on behalf of Oregon State University


A system and method of tracking physical activity of a person in order to help motivate that person to add more exercise to their lives. Each participant is provided a motion sensor that detects forces incurred by the participant. The motion sensor creates electronic data that corresponds to the forces detected. The data is analyzed to determine whether or not exercise has been performed. The analysis can also determine the type of exercise performed, when the exercise was performed, and the duration of the exercise performed.

1. Field of the Invention
In general, the present invention relates to systems and methods that are used to track the health and wellbeing of people within a targeted group. More particularly, the present invention relates to systems and methods that utilize interactive software to both promote and track physical activity among participants in the targeted group.
2. Description of the Background
It is a well-established fact that people generally live longer, healthier lives if they get regular physical activity. It is also a well-established fact that people are more likely to start and continue a lifestyle of physical activity if they have peers and friends that are also participating in that exercise program. Recognizing the above stated facts, many companies have developed employee exercise programs. The hope is that these programs would lead to healthier employees and healthier employees would use less sick days and have lower healthcare costs. By offering exercise programs at work, it is hoped that employees would exercise with peers and would benefit from the support of peers.
Difficulties develop, however, when the management of a company tries to develop exercise programs for their employees. The problem is that many people are not yet behaviorally ready to "exercise" and that not all of those who are enjoy the same types of exercise. As such, a company gym may only appeal to some employees, while a company softball team may appeal to others. Recognizing that different people like different things, exercise programs have been developed that are highly flexible to fit the varied needs and wants of a company's employees. In such exercise programs, the management of a company does not concern itself with what physical activity is being performed. Rather, the company just monitors whether physical activity is being performed and often offers incentives to employees to start and maintain physical activity as part of their daily routines.
The most common way that companies monitor whether or not an employee is performing exercise is to provide the employees with interactive computer software. Using the software, an employee can enter what exercise has been performed. This information is then stored in a database for access by the company. Such exercise monitoring software systems are exemplified by U.S. Patent Application Publication No. 2006/0287883 to Turgis, entitled Interactive Internet Supported Health And Fitness Management System; U.S. Patent Application Publication No. 2007/0072154 to Kaufman, entitled Lifesytle Coach Behavior Modification System; and U.S. Patent Application Publication No. 2007/0100595 to Earles, entitled Behavior Monitoring And Reinforcement System and Method.
The problem associated with such prior art exercise monitoring software systems is that the systems require that an individual manually input data into a computer to inform the computer of what exercise has been performed. Since many of these systems provide rewards for exercise, there is a good incentive for people to lie about exercising or exaggerate in order to receive the reward. Furthermore, people quickly grow tired of tasks in which they are not interested. Employees that must voluntarily enter and log their daily exercise routines may quickly develop user fatigue. Employees may forget to enter data daily and when they do enter data, that data may contain guesses and inaccurate remembrances of days past.
Alternatively, some companies use activity tracking technology that "docks" to a computer to offload the activity data. The problem associated with this type of connection is that it often is inconvenient or cumbersome for the individual to gain access to the computer and as such the participation levels drop off quickly.
Another problem associated with such prior art exercise systems is that it is difficult for an employee to equate different exercises with one another. For example, how may miles of kayaking equate to how many hours of playing tennis? This difficultly in equating exercises makes it very difficult to establish goals for rewards. It also makes it very difficult to set up challenges and competitions among participants that would promote further exercise.
The notion of challenges and competitions is well established, wherein individuals can compete with each other or create teams that compete against one another. However, when working with an organization that has thousands of employees and hundreds of different groups, it has historically been very difficult for an administrator to easily turn those groups into competitive fitness teams, and/or to create challenges between and among such groups and/or teams. This has significantly limited the ability of organizations to leverage the natural social support network of departments, internal work groups, project colleagues, and/or geographic locations into a healthier organizational culture.
A need therefore exists for an exercise system that both passively and accurately monitors the amount of exercise performed by an individual, thereby reducing cheating and user fatigue. A need also exists for an exercise system where all exercises are automatically reduced to comparable units, thereby enabling all exercises to be compared for use in challenges and competitions. A need also exists for an exercise system whereby data collected automatically and passively offloads to a central database, thereby eliminating the need for active intervention by the individual to participate in the program. Finally, a need also exists to allow an administrator to easily set up challenges and competitions between varying sizes and numbers of groups. These needs are met by the present invention as described and claimed below.

System and method for promoting and tracking physical activity among a participating group of individuals


A control valve for injectors of injection systems for internal combustion engines is proposed, in which the final control element is actuated by an actuator via a hydraulic booster.

The invention relates to a double-switching control valve for the injector of a fuel injection system for internal combustion engines, having a final control element actuated by an actuator, wherein the final control element and a bore of a housing form a radially defined annular chamber, which on its ends has a first recess and a second recess, and the final control element is axially displaceable by means of a tappet guided in a first guide bore and has both means for sealing off the annular chamber from the first recess and means for sealing of annular chamber from the second recess.
The object of the invention is to furnish a double switching control valve for an injector of a fuel injection system which allows the metering of the tiniest preinjection quantities and which is constructed simply and compactly.
This object is attained according to the invention by a control valve for the injector of a fuel injection system for internal combustion engines, having a final control element actuated by an actuator, wherein the final control element and a bore of a housing form a radially defined annular chamber, which on its ends has a first recess and a second recess, and the final control element is axially displaceable by means of a tappet guided in a first guide bore and has both means for sealing off the annular chamber from the first recess and means for sealing off the annular chamber from the second recess, and wherein the tappet is actuated by the actuator by means of a hydraulic booster.
The control valve of the invention has the advantage that the hydraulic booster shortens the switching times. The control pressure of the injector builds up an initial tension counter to the actuation direction of the actuator, so that the hydraulic booster does not become operative until it has built up a suitable counterpressure and is already in motion. Because of the very short switching times, very small preinjection quantities can also be metered. In addition, the control valve of the invention is simple in construction and consequently compact.
Variants of the invention provide that the first recess is in communication with a fuel return, and that the second recess is in communication with a control chamber, so that the demand for driving energy for the actuator is only slight, since only during the preinjection does the actuator have to perform work counter to the hydraulic forces acting on the final control element. Furthermore, the actuator is subject only to pressure stress, which is especially advantageous when piezoelectric actuators are used.
In a feature of the invention, the face end, remote from the final control element, of the tappet and a piston actuated by the actuator define a fluid-filled pressure chamber of the hydraulic booster, so that the travel or force boosting is effected simply and with little loss.
Another variant provides that a closing spring is present, which acts on the final control element counter to the actuation direction of the actuator, so that even if pressure is absent in the control chamber, the control valve always has a defined switching position, and the sealing action in the switching position between the main injection and the preinjection is improved.
Further in the invention, it is provided that the closing spring is disposed in the second recess and is braced against a shoulder in the housing and against the final control element, so that the engineering effort and expense are low. In a further embodiment, the closing spring is disposed in a third recess, which adjoins the control chamber, and is braced via a thrust rod, guided in a second guide bore, against the final control element and a Seeger ring that is disposed in an annular groove in the third recess, so that the second recess and the diameter of the second sealing seat can be kept small.
In a further variant, it is provided that the closing spring is disposed in a third recess, which adjoins the control chamber, and is braced via a thrust rod, guided in a second guide bore, against the final control element and a control piston protruding into the control chamber, so that a closing spring with a low spring rate and a small diameter can be used.
In a further embodiment, the thrust rod has at least one longitudinally extending groove, longitudinal bore, or flat face extending essentially over the length of the thrust rod, so that a hydraulic communication exists between the control chamber and the second recess. Furthermore, by suitable dimensioning of the groove, longitudinal bore or flat face, the function of the outlet throttle can be integrated into the thrust rod.
In one version of the invention it is provided that the final control element has a collar disposed coaxially to the longitudinal axis of the tappet, and that the means for sealing off the annular chamber from the second recess and/or the means for sealing off the annular chamber from the first recess have a frustoconical sealing cone disposed coaxially to the longitudinal axis of the tappet, so that over the entire service life of the control valve, good sealing action is achieved.
Further in the invention, the second sealing cone is part of a sleeve disposed coaxially to the longitudinal axis of the final control element, facilitating assembly, and the sleeve is also centered by the tappet.
A variant provides that the end face of the sleeve toward the final control element is smooth, and that the end face of the final control element toward the sleeve is smooth, so that the sleeve is centered not by the control piston but rather by the second sealing seat, and the sealing cone of the sleeve rests in the best possible way on the sealing face in the housing. The aforementioned smooth end faces furthermore seal off the annular chamber from the control chamber.
In a further feature of the invention, it is provided that the end face of the sleeve toward the final control element and the end face of the final control element toward the sleeve are frustoconical, so that the sleeve is centered by the tappet. Furthermore, the aforementioned end faces seal the annular chamber off from the control chamber.
In a further feature of the invention, the sleeve is separably joined to the final control element, so that assembly is simplified and there is no need to split the housing.
Another variant provides that the final control element is embodied spherically, and that the means for sealing off the annular chamber from the second recess and/or the means for sealing off the annular chamber from the first recess are sealing lines extending over the spherical surface, so that an especially compact, simple construction is achieved. Furthermore, the first guide bore and the first and second sealing seat need not be precisely aligned, since the spherical valve member centers itself.
In addition, between the bore and both of the first and second recesses, sealing faces are embodied, which cooperate with the means for sealing off the annular chamber from the first recess and/or the means for sealing off the annular chamber from the second recess, so that a still further improved sealing is achieved.
Further in the invention, it is provided that the housing is embodied in one piece, so that the number of sealing faces is reduced.
In one embodiment of the invention, the control valve is operated as a 2/3-way control valve, so that the metering of the tiniest preinjection quantities is improved, and at the same time large main injection quantities become possible.
In a variant of the invention, the actuator is a piezoelectric actuator, so that major forces and a rapid response are assured.
Further in the invention, it is provided that the injection system is a common rail injection system, so that the advantages of the control valve of the invention also benefit these injection systems.
The object stated above is also attained by an injector for a fuel injection system for internal combustion engines, having a control chamber controlled by a control valve, wherein the control valve has a final control element actuated by an actuator, wherein the final control element and a bore of a housing form a radially defined annular chamber, which on its ends has a first recess and a second recess, and the final control element is axially displaceable by means of a tappet guided in a first guide bore and has both means for sealing off the annular chamber from the first recess and means for sealing off the annular chamber from the second recess, and wherein the tappet is actuated by the actuator by means of a hydraulic booster.
The control valve of the invention has the advantage of shortened switching times. The control pressure of the injector builds up an initial tension counter to the actuation direction of the actuator, so that the hydraulic booster does not become operative until it has built up a suitable counterpressure and is already in motion. Because of the very short switching times, very small preinjection quantities can also be metered. In addition, the control valve of the invention is simple in construction and consequently compact.

Double-switching control valve for an injector of a fuel injection system for internal combustion engines, with hydraulic boosting of the actuator


A vanadium-based catalyst is treated with a polysiloxane oil as a means of enhancing catalyst activity and polymer productivity.

U.S. Pat. No. 4,508,842 discloses a highly active vanadium-containing catalyst capable of producing ethylene polymers having a broad molecular weight distribution. Said catalyst comprises:
(A) a solid catalyst component
consisting essentially of
(1) an inorganic carrier, as support for PA1 (2) the reaction product of (a) a vanadium trihalide and (b) an electron donor, and PA1 (3) a boron halide or alkyl-aluminum modifier, PA1 (1) a solid catalyst component obtained by precipitating vanadium trihalide from an ether solution onto a silica and/or alumina carrier and then treating the product with an alkylaluminum, PA1 (2) an alkylaluminum, PA1 (3) an alkyl halide, and PA1 (4) an alkoxy compound of silicon. PA1 (1) a solid, particulate, porous inorganic carrier, as support for PA1 (2) the reaction product of (a) a vanadium trihalide and (b) an electron donor, and PA1 (3) a boron halide or alkylaluminum modifier, PA1 n is a number having a value of from 2 to 100, PA1 R.sup.1 is hydrogen or a monovalent hydrocarbon radical free of aliphatic unsaturation containing from 1 to 20 carbon atoms, PA1 R.sup.2 is a monovalent hydrocarbon radical free of aliphatic unsaturation containing from 1 to 20 carbon atoms, and PA1 R.sup.3 is selected from the group consisting of: --X, --R.sup.1, --OR.sup.1, --COOR.sup.1, and --NR.sup.1 R.sup.2 PA1 X is halogen and R.sup.1 and R.sup.2 are as defined above. PA1 (1) a solid, particulate, porous inorganic carrier, as support for PA1 (2) the reaction product of (a) a vanadium trihalide and (b) an electron donor, PA1 (3) a boron halide or alkyl-aluminum modifier, and PA1 (4) a polysiloxane oil activity regulator having the formula: ##STR2## wherein: R.sup.1, R.sup.2, R.sup.3, m and n are as defined above, PA1 (1) a solid, particulate, porous inorganic carrier, as support for PA1 (2) the reaction product of (a) a vanadium trihalide and (b) an electron donor, PA1 (3) a boron halide or alkylaluminum modifier, and PA1 (4) a polysiloxane oil activity regulator having the formula: ##STR3## wherein: R.sup.1, R.sup.2, R.sup.3, m and n are as defined above. PA1 M is boron or AlR.sup.4.sub.(3-a) wherein each R.sup.4 is an alkyl radical containing from 1 to 14 carbon atoms, which radicals may be the same or different, PA1 X is selected from the group consisting of fluorine, chlorine, bromine and iodine, and mixtures thereof, and PA1 a is an integer having a value of 0, 1 or 2, provided that a is 3 when M is boron. PA1 n is a number having a value of from 2 to 100, preferably from 3 to 10, PA1 R.sup.1 is hydrogen or a monovalent hydrocarbon radical free of aliphatic unsaturation containing from 1 to 20 carbon atoms, PA1 R.sup.2 is a monovalent hydrocarbon radical free of aliphatic unsaturation containing from 1 to 20 carbon atoms, and PA1 R.sup.3 is selected from the group consisting of: --X, --R.sup.1, --OR.sup.1, --COOR.sup.1, and --NR.sup.1 R.sup.2 PA1 X is halogen and R.sup.1 and R.sup.2 are as defined above. PA1 R.sup.2, is usually an alkyl radical containing from 1 to 20 carbon atoms, preferably from to 1 to 6 carbon atoms, or an aryl radical containing from 6 to 20 carbon atoms, preferably 6 carbon atoms. R.sup.1 is usually hydrogen or a like alkyl or aryl radical, and R.sup.3 is usually halogen or a like alkyl or aryl radical. Such radicals may be substituted with one or more substituents which are inert under the reaction conditions employed during treatment of and polymerization with catalyst component (A). Typical substituents include chlorine and fluorine. PA1 (1) the reaction product of (a) a vanadium trihalide and (b) an electron donor, PA1 (2) a boron halide or alkylaluminum modifier, and PA1 (3) a polysiloxane oil having the formula: ##STR5## wherein: R.sup.1, R.sup.2, R.sup.3, m and n are as defined above. PA1 R.sup.6 is hydrogen or an unsubstituted or halosubstituted alkyl radical containing from 1 to 6 carbon atoms, which radicals may be the same or different, PA1 X' is halogen, and PA1 b is 0, 1 or 2.
(B) an alkylaluminum cocatalyst, and
(C) a halohydrocarbon polymerization promoter.
The polymers produced in accordance with U.S. Pat. No. 4,508,842 have a relatively broad molecular weight distribution, and excellent extrudability. These properties render them extremely useful in a wide variety of applications, such as wire and cable insulation, blow molding, film, and pipe fabrication.
Copending application Ser. No. 292,268 (now U.S. Pat. No. 4,000,327) of Sun-Chueh Kao et al. discloses that the activity of the catalyst disclosed in U.S. Pat. No. 4,508,842, supra, can be enhanced by treating the solid component thereof with an alkoxysilicon compound. However, such treatment also causes a narrowing of the molecular weight distribution of the polymers produced with such catalyst.
Japanese Public Disclosure No. 62-25112 (Application Ser. No. 60-163525) likewise discloses vanadium-containing catalyst compositions useful in the preparation of ethylene polymers having a narrow molecular weight distribution. Such compositions consist of:
Japanese Public Disclosure No. 56-22308 (Application Ser. No. 54-981281) is yet another reference which discloses vanadium-containing catalyst compositions useful in the preparation of ethylene copolymers having a narrow molecular weight distribution. The catalyst compositions of this reference are prepared by combining an organoaluminum compound and a solvent-soluble vanadium compound in the presence of olefin monomer and then adding polysiloxane to the mixture.

Union Carbide Chemicals and Plastics Technology Corporation


Example magnetic resonance imaging (MRI) radio frequency (RF) coils employ flexible coaxial cable. An MRI RF coil may include an LC circuit and an integrated decoupling circuit. The LC circuit includes one or more flexible coaxial cables having a first end and a second end, the one or more flexible coaxial cables having an inner conductor, an outer conductor, and a dielectric spacer disposed between the inner conductor and the outer conductor, where the outer conductor of the coaxial cable is not continuous between the first end and the second end at a first location. The integrated decoupling circuit may include a PIN diode and a tunable element. The tunable element may be tunable with respect to resistance, capacitance, or inductance, and thus may control, at least in part, the frequency at which the LC circuit resonates during RF transmission, or an impedance at the first location.

Magnetic resonance imaging (MRI) involves the transmission and receipt of radio frequency (RF) energy. RF energy may be transmitted by a coil. Resulting magnetic resonance (MR) signals may also be received by a coil. Conventionally, RF energy has been transmitted from a single coil and resulting MR signals received by a single coil. Multiple receivers may be used in parallel acquisition techniques. Similarly, multiple transmitters have been used in parallel transmission techniques.
RF coils create the B1 field that rotates the net magnetization in a pulse sequence. RF coils may also detect precessing transverse magnetization. Thus, RF coils may be transmit (Tx) coils, receive (Rx) coils, or transmit and receive (Tx/Rx) coils. Typically, the transmitted RF signals are orders of magnitude larger than the MR signals generated by the excited nuclei and detected by the RF Rx coils. To protect the Rx coils and receiver circuits and apparatus, the Rx coils may be decoupled or detuned while RF is being transmitted by an MR apparatus. The decoupling or detuning may be active or passive. Active decoupling involves, for example, applying a bias to a PIN diode semiconductor switch in conjunction with an LC circuit during RF transmission. Passive decoupling involves, for example, using antiparallel diode semiconductor switches in conjunction with LC circuitry. The antiparallel diode semiconductor switches are switched upon detecting high power RF transmit pulses, which allows high currents, but not low currents, to interact with the parallel resonant LC circuit that decouples the coil.
An imaging coil needs to be able to resonate at a selected Larmor frequency. Imaging coils include inductive elements and capacitive elements. The resonant frequency, v, of an RF coil is determined by the inductance (L) and capacitance (C) of the inductor capacitor circuit according to:
  v  =      1          2            Π                    LC
Imaging coils may need to be tuned. Tuning an imaging coil may include varying the performance of a capacitor. Recall that frequency: f=ω/(2π), wavelength: λ=c/f, and λ=4.7 m at 1.5 T. Recall also that the Larmor frequency: f0=γB0/(2π), where γ/(2π)=42.58 MHz/T; at 1.5 T, f0=63.87 MHz; at 3 T, f0=127.73 MHz; at 7 T, f0=298.06 MHz. Basic circuit design principles include the fact that capacitors add in parallel (impedance 1/(jCω)) and inductors add in series (impedance jLω).
When MRI coils that are tuned to the same radio frequency are positioned close together, which may occur, for example, in phased array coils, the MRI coils may inductively couple to each other, which causes the MRI coils to detune each other. Detuning due to inductive coupling reduces image quality as compared to using single coils individually. Conventional phased array coils may address the detuning due to inductive coupling problem by overlapping coils or by using preamplifiers that dampen current flow in individual coils.
Referring to Prior Art FIG. 1, a single RF coil segment 102 is illustrated schematically to include an inductance 103, a resistance 104, and a capacitance 105. Capacitance 105 is selected to tune the segment 102 to a desired frequency (e.g., Larmor frequency). The RF coil segment 102 is connected across the output of a current control circuit 106 that is driven by an input signal 107 to produce a current in the RF coil segment 102. Unfortunately, an additional induced current may also flow through the RF coil segment 102 due to signals indicated at 108 induced by currents flowing in other (e.g., adjacent) RF coil segments. With multiple driving loops tuned at a single image frequency, which may occur in a phased array coil, the current on a loop is a superposition of the driven current and currents induced by other transmitters due to electromagnetic induction.
Conventionally, attempts to reduce, minimize, or eliminate the coupling through the mutual impedance in two interacting elements may have been attempted by cancelling the mutual impedance or by reducing the current in the coil. Mutual inductance may be cancelled by either partial overlap of adjacent coils, which may be referred to as transformer type decoupling, or by using decoupling capacitors. Other conventional approaches include using a preamplifier decoupling network to isolate coil elements by creating a large impedance block at the terminals of a receive element, which suppresses currents driven by the spin induced electromotive force (emf).
There are many design issues associated with MRI RF coil design. For example, the inductance of a conventional coil depends on the geometry of the coil. For a square coil with a side length a and wire diameter f: L=[μ0/π] [−4a+2a√2−2a log(1+√2)+2a log(4a/f)]. For a loop coil with loop diameter d and wire diameter f: L=[μ0d/2] [log(8d/f)−2]. Thus, the selection of the geometry of a coil determines, at least in part, the inductance of the coil.
The resistance of a coil also depends on the geometry of the coil. The resistance R of a conductor of length l and cross-sectional area A is R=ρl/A, where ρ is the conductor resistivity and is a property of the conductor material and the temperature. For a copper wire coil with loop diameter d and wire diameter f: R=dρCu/(fδCu). For a copper foil coil with loop diameter d, copper thickness t, and copper width w: R=πdρCu/(2wδCu), where t is much greater than the copper skin depth and w is much greater than t. Thus, the selection of the geometry of a coil and the material (e.g., wire, foil) determines, at least in part, the inductance of the coil. The length of the loop also impacts the properties of the coil.
Coils may be characterized by their signal voltage, which is the electromotive force (emf) induced in a coil: ξ=−∂φ/∂t∝−∂(B1·M0)/∂t, where φ is the magnetic flux across the coil (closed loop), magnetization M0=Nγ2(h/(2π))2s(s+1)B0/(3kBTS)=σ0B0/μ0, where N is the number of nuclear spins s per unit volume (s=½ for protons) and TS is the temperature of the sample. Since ω0=γB0, ξ∝ω02. The noise in a coil may be thermal (e.g., v=(4kBTSRΔf)1/2, where R is the total resistance and Δf is the bandwidth of the received signal). The signal to noise ratio (SNR) for a coil may be described by ξ/v.
Coils may be used for transmitting RF energy that is intended to cause nuclear magnetic resonance (NMR) in a sample. The frequency at which NMR will be created depends on the magnetic field present in the sample. Both the main magnetic field B0 produced by the MRI apparatus and the additional magnetic field B1 produced by a coil contribute to the magnetic field present in the sample. For a circular loop coil, the transmit B1 field equals the coil sensitivity. A circular loop of radius a carrying a current I produces on axis the field: B=μ0Ia2/[2 (a2+z2)3/2].
RF coils for MRI may need to be tuned and matched. Tuning involves establishing or manipulating the capacitance in a coil so that a desired resistance is produced. Matching involves establishing or manipulating the capacitance in a coil so that a desired reactance is achieved. When tuning, the impedance z may be described by Z=R+jX=1/(1/(r+jLω)+jCω). Tuning may be performed to achieve a desired tuning frequency for a coil. ω0 identifies the desired tuning frequency. ω0, may be, for example, 63.87 MHz at 1.5 T. The size of a conventional coil facilitates estimating inductance L. With an estimate of L in hand, values for capacitors can be computed to produce a desired resonant peak in an appropriate location with respect to ω0. Once capacitors are selected, the resonant peak can be observed and a more accurate L can be computed. The capacitors can then be adjusted to produce the desired resistance. Once the desired resistance is achieved, then capacitance can be adjusted to cancel reactance.
MRI RF coils may use PIN diodes. When forward-biased, a PIN diode may produce a negligible resistance (e.g., 0.1Ω), which is essentially a short-circuit. When reverse-biased, a PIN diode may produce a high resistance (e.g., 200 kΩ) in parallel with a low capacitance (e.g., −2Ω), which is essentially an open-circuit.
Thus, conventional coil design may be a complicated process that requires numerous decisions. Additionally, conventional coil fabrication may be a complicated process that requires accurately implementing manufactures that reflect the design decisions.
Prior Art FIG. 2 illustrates a schematic of a simple conventional RF coil 200 for MRI. The coil 200 is illustrated as a loop 210. Loop 210 has elements that produce a resistance (R) (e.g., resistor 220) and that produce an inductance (L) (e.g., inductor 230). A conventional loop may include a matching capacitor 240 and tuning capacitor 250 that produce capacitance (C). The simple RF coil 200 may be referred to as an LC coil or as an RLC coil. Conventionally, the resistor 220, inductor 230, and capacitor 250 may all have been two terminal passive elements that were soldered to copper wire or copper foil that was attached to a printed circuit board.
A resistor may be, for example, a passive, two-terminal electrical component that implements electrical resistance as a circuit element. Resistors reduce current flow. Resistors also lower voltage levels within circuits. Resistors may have fixed resistances or variable resistances. The current that flows through a resistor is directly proportional to the voltage applied across the resistor's terminals. This relationship is represented by Ohm's Law: V=IR, where I is the current through the conductor, V is the potential difference across the conductor, and R is the resistance of the conductor.
An inductor, which may also be referred to as a coil or reactor, may be a passive two-terminal electrical component that resists changes in electric current. An inductor may be made from, for example, a wire that is wound into a coil. When a current flows through the inductor, energy may be stored temporarily in a magnetic field in the coil. When the current flowing through the inductor changes, the time-varying magnetic field induces a voltage in the inductor. The voltage will be induced according to Faraday's law and thus may oppose the change in current that created the voltage.
A capacitor may be a passive, two-terminal electrical component that is used to store energy. The energy may be stored electrostatically in an electric field. Although there are many types of practical capacitors, capacitors tend to contain at least two electrical conductors that are separated by a dielectric. The conductors may be, for example, plates and the dielectric may be, for example, an insulator. The conductors may be, for example, thin films of metal, aluminum foil or other materials. The non-conducting dielectric increases the capacitor's charge capacity. The dielectric may be, for example, glass, ceramic, plastic film, air, paper, mica, or other materials. Unlike a resistor, a capacitor does not dissipate energy. Instead, a capacitor stores energy in the form of an electrostatic field between its conductors.
When there is a potential difference across the conductors, an electric field may develop across the dielectric. The electric field may cause positive charge (+Q) to collect on one conductor and negative charge (−Q) to collect on the other conductor.
Prior Art FIG. 3 illustrates a schematic of another simple RF coil 300 for MRI. RF coil 300 may also be referred to as an LC coil or as an RLC coil. The coil 300 is illustrated as a square loop 310. Loop 310 has elements that produce a resistance (e.g., resistor 320) and that produce an inductance (e.g., inductor 330). A conventional loop may include a capacitor 340 and capacitor 350 that work together to achieve matching. Once again, the resistor 320, inductor 330, and capacitors 340 and 350 may have been soldered to copper wire or copper foil that was attached to a printed circuit board. Coil 300 is contrasted with coil 200 (Prior Art FIG. 2) that included capacitor 250 for tuning purposes.
Prior Art FIG. 4 illustrates a conventional RLC coil 400 that performs traditional "distributed" decoupling using components L41 and D41. Coil 400 includes capacitors C41, C42, C43, and inductors L41, L42, and L43. Coil 400 includes a pre-amplifier circuit 410. Coil 400 also includes a PIN diode D41. Recall that a PIN diode has a wide, lightly doped near intrinsic semiconductor region positioned between a p-type semiconductor region and an n-type semiconductor region that are used for ohmic contacts. The wide intrinsic region makes the PIN diode suitable for fast switches. Fast switching may be employed in MRI coils. In transmit mode, the PIN diode D41 may be turned off.
In conventional coil 400, a single capacitor C42 is illustrated to represent one or more capacitors that may be employed in the coil 400. Thus, capacitor C42 may be an equivalent capacitor of multiple breaking point capacitors that may appear in coil 400. Inductor L42 represents the inductance of the coil. The inductance may be produced, for example, by a copper trace that forms the coil 400.
In the conventional coil 400, capacitor C41 is the breaking point capacitor that is used for decoupling the coil 400 from other MRI coils. Capacitor C41 and inductor L41 are in parallel resonance and the impedance across capacitor C41 is high. Capacitor C41 is a single high impedance point in coil 400. Since the impedance across capacitor C41 is high, an induced voltage on coil 400 cannot generate a large current through capacitor C42. In a conventional coil like coil 400, the single high impedance point (e.g., capacitor C41) may get unacceptably or dangerously hot producing heat dissipation issues that in turn limit the operation of coil 400.

Flexible coaxial magnetic resonance imaging (MRI) coil with integrated decoupling


A communication device is operative to generate and orthogonal frequency division multiplexing (OFDM) symbol that includes one or more data and ranging modulation symbols. The data and ranging modulation symbols may be included within different sub-carriers of the OFDM symbol. The OFDM symbol is used to generate an OFDM symbol pair in the frequency domain (FDOM). After conversion from the FDOM to the time domain (TDOM), the OFDM symbol pair may then undergoes post-processing in the TDOM before transmission. Such post-processing may include the addition of cyclic prefix (CP) and cyclic suffix (CS) to the OFDM symbol pair in the TDOM as well as filtering using a window function. The OFDM symbol may be generated as an orthogonal frequency division multiple access (OFDMA) symbol, and two were more OFDM symbols or OFDMA symbols may be arranged in a frame.

1. Technical Field
The present disclosure relates generally to communication systems; and, more particularly, to ranging within such communication systems.
2. Description of Related Art
Data communication systems have been under continual development for many years. The primary goal within such communication systems is to transmit information successfully between devices. Communications between devices can be governed by a number of operational parameters. Ranging is a process by which characteristics of the communication pathway between first and second communication devices can be determined.
A first communication device transmits a ranging signal to a second communication device, and the second communication device processes the ranging signal to determine one or more characteristics of the communication pathway between the first and second communication devices. Then, the second communication device communicates with the first communication device using one or more operational parameters that are selected based on the one or more characteristics of that communication pathway. Examples of such operational parameters may relate to transmission power and timing based on the distance between the first and second communication devices as well as any particular characteristics of the communication pathway between them.

OFDM or OFDMA signaling for ranging and data


A dialogue apparatus includes a display unit, a first dialogue control unit configured to display a first character on the display unit and simulate a speech function of an external communication robot capable of having a dialogue to conduct the dialogue with a user, a second dialogue control unit configured to display a second character on the display unit and conduct the dialogue so as to mediate the dialogue between the user and the first dialogue control unit, and a transmission unit configured to transmit, to the external communication robot, dialogue information about the dialogue conducted by the first dialogue control unit and the second dialogue control unit.

The present disclosure relates to a dialogue apparatus and a control program of the dialogue apparatus.
Service providing robots capable of autonomous movement are coming into practical use. Some of these service robots include a voice recognition function and a speech function and communicate with a user through dialogues (see, for example, Japanese Unexamined Patent Application Publication No. 2012-86348).
Communication robots capable of autonomous movement are often available to a user only at limited places. Thus, it may be difficult for the user to feel attached to the communication robot or for the communication robot to acquire the user's temperament. Thus, in a situation where the communication robot is not available, an application which allows the user to communicate with a character reproducing the communication robot in a pseudo manner on a mobile terminal such as a smartphone has come to be known. When the communication robot receives a result of repeated communication, on the mobile terminal, between the user and the character from the mobile terminal as history information of the communication, the communication robot can communicate appropriately with the user. The user eventually feels attached to the communication robot through such communication.

Dialogue apparatus and control program for dialogue apparatus


An electrolyte solution for a potassium ion battery or a potassium ion capacitor, the electrolyte solution comprising at least one potassium salt compound selected from the group consisting of potassium bis(trifluoromethanesulfonyl)amide and potassium bis(fluorosulfonyl)amide and at least one solvent selected from the group consisting of ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, pentaethylene glycol dimethyl ether, ethylene carbonate, and propylene carbonate, in which a concentration of the potassium salt compound in the electrolyte solution is from 1.5 mol/kg to 12.0 mol/kg.

At present, as a high energy density secondary battery, a non-aqueous electrolyte secondary battery is widely used, for example, in which a non-aqueous electrolyte is used and lithium ions are transferred between a positive electrode and a negative electrode to perform charging and discharging.
In such non-aqueous electrolyte secondary batteries, generally, lithium transition metal complex oxide having a layered structure such as lithium nickelate (LiNiO2) or lithium cobaltate (LiCoO2) is used as a positive electrode, and a carbon material capable of absorbing and desorbing lithium, lithium metal, lithium alloy, or the like is used as a negative electrode (see, for example, Japanese Patent Application Laid-Open (JP-A) No. 2003-151549).
As a positive electrode of a non-aqueous electrolyte secondary battery, one described in Japanese National-Phase Publication (JP-A) No. 2015-515081 is known.
As a secondary battery that can be charged and discharged, a lithium ion secondary battery capable of achieving high energy density at high voltage have been mainly used so far, but the amount of lithium resources is relatively limited, and lithium is expensive. Lithium resources are localized in South America, and Japan relies entirely on imports from overseas. Under such circumstances, a sodium ion secondary battery replacing a lithium ion secondary battery is currently under development for cost reduction and stable supply of batteries. However, sodium has a larger atomic weight than lithium, a standard electrode potential of about 0.33 V higher than lithium, and a low cell voltage, and therefore, there is a problem that it is difficult to achieve high energy density.
As an electrolyte solution used for a lithium ion battery, those described in WO2013/146714 or Y. Yamada and A. Yamada, "Review-Superconcentrated Electrolytes for Lithium Batteries", Journal of the Electrochemical Society, 162, A2406-A2423 (2015) are known.
Recently, research on non-aqueous electrolyte secondary batteries using potassium ion instead of lithium ion and sodium ion has been started.
Since an electrode active material constituting a potassium ion secondary battery, in particular, a positive electrode active material must be a source of potassium ions, such an active material needs to be a potassium compound containing potassium as a constituent element. At present, as a positive electrode active material for a potassium ion secondary battery, for example, those consisting of crystalline K0.3MnO2 having a layered rock salt type structure (see Christoph Vaalma, et al., Journal of The Electrochemical Society, 163 (7), A1295-A1299 (2016)), those consisting of a Prussian blue-based material crystal (see Ali Eftekhari, Journal of Power Souces, 126, 221-228 (2004)), and the like are known.

Electrolyte solution for potassium ion battery, potassium ion battery, electrolyte solution for potassium ion capacitor, and potassium ion capacitor


Methods and apparatus for calibrating an antenna array are provided. A limited number of antenna elements of the array are operated to broadcast a signal. The signal carries information relevant to operation of a communication network, for receipt by other devices. By using one or a limited number of antenna elements, a radiation pattern covering a wide area is achieved. Concurrently, transmission of the broadcast signal is monitored using another one or more antenna elements of the array, operating in a receive mode. The monitored signal is used in an antenna array calibration operation. The procedure is repeated for various different transmitting and receiving antenna elements, resulting in a sequence of broadcasts using different parts of the array. The calibration results can be used to correct for operating errors such as phase shifter errors. The corrected phase shifters can then be used for beamforming during another phase of communication.

Phased antenna arrays are a popular means for generating a configurable antenna radiation pattern for wireless transmission or reception. A narrow beam antenna radiation pattern can be formed using an array of antenna elements in cooperation with phase shifters. The antenna elements are operated in a coherent manner so as to focus the beam in a desired direction. Beamforming and beam steering using this approach is widely known in the art. However, gain and phase mismatches among elements of the antenna array can impact performance. For example, Ming-Da Tsai and Arun Natarajan, "60 GHz Passive and Active RF-path Phase Shifters in Silicon," 2009 IEEE Radio Frequency Integrated Circuits Symposium reports a typical 3° RMS error or maximum 10° error for phase shifters operating in the 60 GHz frequency range. Phase and gain variation among phase shifters and amplifiers can be temperature dependent and/or introduced as an artifact of the manufacturing process.
One technique for calibrating phased array antennas is described in Herbert F. Aumann et al., "Phased Array Antenna Calibration and Pattern Prediction Using Mutual Coupling Measurements," IEEE Transactions on Antennas and Propagation, vol. 37, No. 7, July 1989, pp. 844-850. This reference is hereinafter referred to as Aumann. This approach utilizes the inherent mutual coupling in an array to both calibrate and predict the radiation patterns. Other techniques for far field array calibration involve the use of calibration chambers, or the use of far field sampling points as in radar applications. However, existing calibration techniques call for specialized equipment and/or a dedicated calibration process, during which the antenna is not available for communication operations.
Therefore there is a need for a method and apparatus for antenna array beamforming calibration, that obviates or mitigates one or more limitations of the prior art.
This background information is provided to reveal information believed by the applicant to be of possible relevance to the present invention. No admission is necessarily intended, nor should be construed, that any of the preceding information constitutes prior art against the present invention.

Method and apparatus for beamforming calibration in point to multipoint communication systems


A phase locked loop (PLL) includes a detector, a charge pump, a loop filter, a voltage controlled oscillator (VCO), a divider, and a frequency change module. The detector provides a phase difference based on a reference signal and a feedback signal. The charge pump provides a charge based on the phase difference. The loop filter provides a voltage based on the charge. The VCO provides an output signal based on the voltage received from the loop filter. The divider divides a frequency of the output signal by a value to provide the feedback signal. The frequency change module processes an input signal having a first frequency to provide a processed signal having a second frequency that is different from the first frequency. The frequency change module selects the input signal or the processed signal to provide as the reference signal to the detector. Changing the frequency of the reference signal can change a frequency of a spur.

1. Field of the Invention
The present invention relates generally to circuitry, and more specifically to circuitry that includes a phase locked loop (PLL).
2. Background
Phase locked loops (PLLs) are used in any of a variety of systems, such as wireless and wire line communication systems, to synchronize signals.
In a PLL, a phase detector compares a feedback signal and a reference signal to generate a phase error signal. The phase error signal indicates a phase difference between the feedback signal and the reference signal. A charge pump provides a charge based on the phase error signal. A loop filter provides a voltage based on the charge. A voltage controlled oscillator (VCO) generates a system output signal having a frequency that is based on the voltage provided by the loop filter. A divider divides the frequency of the system output signal by a value to generate the feedback signal. The value utilized by the divider can be an integer or a non-integer.
Utilizing an integer value to generate the feedback signal provides a system output signal having a frequency that is an integer multiple of the frequency of the reference signal. Utilizing a non-integer value enables the PLL to provide a system output signal having a frequency that is a non-integer multiple of the frequency of the reference signal. However, generating the non-integer value gives rise to spurs. For example, the system output signal can have sidebands that negatively impact the performance of the PLL. Such spurs can reduce the signal-to-noise ratio (SNR) of the reference signal and/or degrade the bit error rate (BER) of the PLL.
What is needed, then, is a system and method that addresses one or more of the aforementioned shortcomings of conventional PLLs and feedback techniques.
In the drawings, like reference numbers indicate identical or functionally similar elements. Additionally, the leftmost digit(s) of a reference number identifies the drawing in which the reference number first appears.

Phase locked loop including a frequency change module


A vehicle disabling apparatus for remotely disabling a vehicle having an engine comprises a source (4) of high frequency energy for generating a high frequency signal and a modulator (1) for modulating the high frequency signal by applying an effects signals package. The effects signal package comprises a plurality of respective effects signals and each effects signal comprises a pulse train, the effects signals package being non-vehicle specific. An antenna (6) directs the effects signal package modulated signal at a remote vehicle to disrupt the vehicle engine by affecting the target vehicle engine management system.

There is a requirement to be able to stop vehicles for law enforcement or security purposes. This may be achieved by applying a lethal solution but it may not be the most desirable outcome and can result in injuries to bystanders, law enforcement officers and collateral damage.
One non-lethal solution is to deploy a mechanical device in the path of a target vehicle to damage its tyres but this can be dangerous for personnel and difficult to position.
In another solution, a high power broadband microwave/VHF source may be employed to direct an electromagnetic pulse at a target vehicle but due to the broadband nature of the signal, which may have little directivity, this could cause damage to vehicle and danger to occupants and bystanders, for example, people with pacemakers being particularly vulnerable.

Method and apparatus for remotely disabling vehicles


An article processing apparatus having a plurality of input conveyors directing articles into a work station and a single turret sorting mechanism. The work station processes articles while, simultaneously, unprocessed articles are fed into the turret sorting mechanism. The output of the work station is simultaneously fed into the turret sorting mechanism. The turret control mechanism engages articles fed to it using a gripper. The turret sorting mechanism rotates the articles until, in conjunction with a control system, the articles are released onto appropriate locations on a second set of conveyors. The second set of conveyors directs the unprocessed articles to a second work station (where the unprocessed articles are processed) and the articles processed by the first work station are directed to an output station. Once processed, the articles sent to the second work station are also directed to the output station where they are collected and prepared for further processing.

In the commercial processing of many different types of articles, such as bottles in a labeling plant, it is desirable to process numerous columns of articles at the same time. The word "article" is used herein as a generic term for any type of vessel, container, bottle, or other items processed by the invention. Ordinarily, articles (such as bottles) are processed on single conveyor lines through a single set of process stations resulting in a completed product. Such a system is shown in FIG. 1. An input station 20 feeds unprocessed articles 10 onto a single conveyor system 21 into a work station 30 (for example, a bottle labeling machine). The articles are processed 10' and conveyed out of the work station 30 on a conveyor system 21 to an output station 38 for further processing. A complete set of process stations (20, 30, 38) are needed to process a single lines of articles. This form of processing is slow, takes up a great deal of space, and in the event of a component or station malfunction, all processing ceases.
The present invention overcomes these difficulties by running many process lines through fewer process stations and using a single sorting mechanism to more efficiently distribute the articles under process to the various stations. This reduces total space needed and effectively increases process efficiency by requiring fewer operators, fewer machines, and easier use.

Turret feed control apparatus for sorting and distributing articles in a process system


The invention relates to methods for producing secondary metabolites using transformed Synechocystis sp. bacteria, and secondary metabolites produced by transformed Synechocystis sp. bacteria. The invention further relates to phosphopantetheinyl transferase enzymes.

Non-ribosomal synthesis allows microorganisms to produce a diverse range of novel compounds including carboxy acids, heterocyclic rings, fatty acids and non-proteinogenic modified amino acids. Small polypeptides are assembled by peptide synthetases just as other compounds, like fatty acids, are linked by other synthetases during synthesis on the ribosome.
Non-ribosomal synthesis provides a pathway of synthesizing compounds which would be expensive or unobtainable using synthetic chemical methods. Nonribosomally synthesised peptides share certain characteristics. These small bioactive peptides are usually between 2 and 50 amino acid residues long and possess potent biological activities. Most examples of these compounds are also highly resistant to physical and chemical degradation making them ideal for use as oral therapeutics. The valuable products of microbial nonribosomal peptide synthesis include the immunosuppressant cyclosporin A and antibiotics such as penicillin, gramicidin S, vancomycin, cephalosporin, and surfactins.
Such compounds are synthesized by complex secondary metabolism pathways involving polyketide synthases (PKS), non-ribosomal peptide synthetases (NRPS) and fatty acid synthases (FAS). These enzymes are activated by phosphopantetheinyl transferases (PPTs). PPTs activate carrier proteins that are essential for PKS, NRPS and FAS activity. PPTs convert inactive carrier proteins to their active, cofactor-bearing holo-forms via transfer of the essential prosthetic 4′ phosphopantetheine moiety from co-enzyme A (CoA) (FIG. 1).
Cyanobacteria constitute a rich source of secondary metabolites with the majority being derived from PKS, NRPS and FAS. Due to their broad intergeneric distribution of integrated enzyme systems, cyanobacteria provide a source of many uncharacterised amino acid activating and modifying peptide synthetase modules. Consequently freshwater and marine cyanobacteria have been screened for bioactivity revealing natural products with novel biological applications and clearly implicating cyanobacteria as a rich source of potentially useful compounds.
Analysis of cyanobacterial non-ribosomal peptide, polyketide and fatty acid synthesis pathways has revealed unforeseen biochemical structures displaying the potential for novel products from cyanobacteria. However the strains of cyanobacteria which synthesize natural compounds are usually strains associated with slower growth or complicated culture requirements. Thus species which produce natural products may be excluded in culture-based screening. Furthermore current natural product screening relies on organism propagation. As less than 1% of microorganisms are estimated to be culturable, however, the bulk of potential bioactivities present in nature is not detectable. Alternatively, time-consuming organic syntheses have been used to create a modified natural product. Although molecular methods may yield the genetic information, recombinant expression in a suitable host organism is required to allow the isolation and production of novel compounds.
The ability to heterologously express and biochemically characterize recombinant proteins and biosynthesis pathways remains a significant problem with respect to cyanobacteria.

Methods for producing secondary metabolites


A remote controller holder for permitting hands free holding a remoter controller by a user. The remote controller holder includes an elongate carrier having spaced apart pair of arm portions and an elongate middle portion connecting the arm portions together. The arm portions each have spaced apart elongate front and back segments, and an elongate bottom segment connecting the front and back segments of the respective arm portion together. The back segments of the arm portions are coupled to the middle portion. The arm portions are designed for resting a remote controller thereon. A generally U-shaped bracket is coupled to the middle portion of the elongate carrier. A bolt is extended through the bracket. The bolt is designed for extending through a looped end of a neck strap secured around a user's neck.

1. Field of the Invention
The present invention relates to remote controller holders and more particularly pertains to a new remote controller holder for permitting hands free holding a remoter controller by a user.
2. Description of the Prior Art
The use of remote controller holders is known in the prior art. More specifically, remote controller holders heretofore devised and utilized are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements.
Known prior art includes U.S. Pat. No. 4,537,340; U.S. Pat. No. 5,551,615; U.S. Pat. No. 3,541,976; U.S. Pat. No. 3,273,484; U.S. Pat. No. 4,699,415; and U.S. Pat. No. Des. 377,876.
While these devices fulfill their respective, particular objectives and requirements, the aforementioned patents do not disclose a new remote controller holder. The inventive device includes an elongate carrier having spaced apart pair of arm portions and an elongate middle portion connecting the arm portions together. The arm portions each have spaced apart elongate front and back segments, and an elongate bottom segment connecting the front and back segments of the respective arm portion together. The back segments of the arm portions are coupled to the middle portion. The arm portions are designed for resting a remote controller thereon. A generally U-shaped bracket is coupled to the middle portion of the elongate carrier. A bolt is extended through the bracket. The bolt is designed for extending through a looped end of a neck strap secured around a user's neck.
In these respects, the remote controller holder according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of permitting hands free holding a remoter controller by a user.


A bearing assembly for use in an electric motor has a temperature-activated stabilizer to reduce vibration. The electric motor has a stator assembly and a rotor assembly and the bearing assembly includes a collar that has an outer diameter that is less than an inner diameter of the stator assembly. The bearing assembly further includes a temperature-activated stabilizer assembly that includes an extensible member positioned within the stabilizer recess. Under a first temperature the extensible member has a first volume and under a second temperature the extensible member expands to a second volume that is larger than the first volume. As the extensible member expands, the extensible member comes into contact with the stator assembly.

Electrodynamic systems such as electric motors, generators, and alternators typically include a stator and a rotor. The stator typically has a metallic core with electrically insulated wire winding through the metallic core to form the stator coil. When current is alternately passed through a series of coils, magnetic flux fields are formed, which cause the rotor to rotate in accordance with electromagnetic physics.
Electrical submersible pumping systems include specialized electric motors that are used to power one or more high performance pump assemblies. The motor is typically an oil-filled, high capacity electric motor that can vary in length from a few feet to nearly fifty feet, and may be rated up to hundreds of horsepower. In submersible motors, the stators usually surround the rotors, which are secured to a center shaft that is used to transfer the output of the motor. In this way, the rotor and shaft spin about a common axis inside the motionless stator.
In longer submersible motors, it may be desirable to employ a number of separate rotor sections within a single stator. Each rotor section is usually constructed from a number of thin, pressed-together pieces of material, or laminations, through which ferromagnetic rods are inserted. The shaft can be secured within the inner diameter of the rotor sections with a keyed connection or by one of several other well-known methods.
When assembling a submersible motor, bearing assemblies are typically placed between adjacent rotor sections to construct a larger rotor assembly. The shaft is outfitted with one or more wear sleeves and is then inserted into the rotor assembly. The shaft and rotor assembly are then inserted into the stator. It is important that the bearing assemblies have a clearance fit within the stator. The clearance fit facilitates the sliding of the rotor assembly into the stator.
Some bearing assemblies further include an anti-rotation key designed to prevent the bearing assemblies from rotating within the stator. There is, however, no current mechanism in the prior art for preventing relative vibrational movement between the bearing assembly and the stator. Vibration in electrical motors is principally the result of imbalance in the rotating mass of the motor rotor and shaft as well as unstable orbit of the shaft within the various bearing assemblies. Such vibrations can be detrimental to the long-term reliability of the equipment. Improvements in rotor balance may reduce the risk of such electrical failures, but cannot be reliably eliminated. Even with stable shaft orbits, high vibration has still been observed in the motor housing and other components connected to the motor housing. There is, therefore, a continued need for a mechanism for stabilizing the bearing assembly relative to the other stationary components of the submersible pump. It is to these and other deficiencies in the prior art that the present invention is directed.

Motor rotor bearing with temperature-activated stabilizers


Indexing documents is accomplished by generating an inverted index for a collection of one or more documents, each document including one or more index terms. The inverted index includes an inverted list for each index term in the collection of documents. One or more inverted lists include a quantity of postings that exceeds a value x, a skip entry after the xth posting, and one or more additional skip entries thereafter at intervals of every yth posting. The value x is such that at least a majority of the index terms occur in x documents or fewer, and the value y is not equal to the value x.

The following disclosure relates to techniques for indexing terms included in a collection of one or more documents.
Search engines can be used to locate keywords or phrases in a collection of documents. A search query typically includes one or more keywords, and can be formed, for example, using Boolean logic, or as a phrase, such as by including the search terms in quotation marks. Examples of commonly used Boolean operators include AND, OR and NOT. A phrase query requires that two or more terms be located in a particular order within a document. Proximity operators used in Boolean logic search queries require two or more search terms to conform to a predefined proximal relationship, for example, a search query may specify that two search terms must occur within five words of each other in a document.
A search engine can evaluate a search query using an inverted index for the collection of documents. An inverted index includes a vocabulary of terms occurring in the documents and an inverted list for each index term. The vocabulary of terms can be arranged in a data structure, such as a B-tree. An inverted list includes one or more postings, where each posting identifies a document in the collection, a frequency of the index term in the identified document, and a list of offsets, which identify positions at which the index term appears in the identified document. For example, a posting in an inverted list for index term t may be configured as follows:                <d, fd,t, [o1, . . . ofd,t]>where d identifies a document in the collection, f is the frequency of occurrences of the term t in the document d, and o1 through ofd,t are offsets identifying positions of the term t in the documented.
A search engine evaluating a query traverses the inverted lists for index terms included in the query. For example, evaluating a query formed using Boolean logic may require traversing more than one list depending on the operator, such as OR (the union of component lists), AND (an intersection of component lists), SUM (the union of component lists), or a proximity operator (an intersection of component lists).
Evaluating a phrase query can be achieved by combining the inverted lists for the query terms to identify matching documents. Alternatively, an auxiliary index can be used, for example, an inverted index that indexes common terms and nextword pairs. 'Stopping' is a technique for evaluating search queries including common terms, where common terms are identified as stopwords and ignored when evaluating a search query.
'Skipping' is a technique to improve query evaluation performance by including synchronization points (skip entries) in a compressed inverted list, to provide additional locations at which decompressing can commence. Skipping allows a relevant portion of a compressed list to be identified and decompressed, without decompressing the entire list.


Graphene, can be used to make an implantable neuronal prosthetic which can be indefinitely implanted in vivo. Graphene electrodes are placed on a 3C—SiC shank and electrical insulation is provided by conformal insulating SiC. These materials are not only chemically resilient, physically durable, and have excellent electrical properties, but have demonstrated a very high degree of biocompatibility. Graphene also has a large specific capacitance in electrolytic solutions as well as a large surface area which reduces the chances for irreversible Faradaic reactions. Graphene can easily be constructed on SiC by the evaporation of Si from the surface of that material allowing for mechanically robust epitaxial graphene layers that can be fashioned into electrodes using standard lithography and etching methods.

One of the problems with long term, implantable biomedical devices arises from the response of the body to one or more of the materials that are used to construct the device, or the degradation of the material due to the body environment. This problem has led to advances in the materials used for mechanical devices that replace bones, joints, and teeth, as well as coronary devices such as arterial stents or artificial heart valves. Biomedical devices gained an entirely new level of complexity with the advent of the microchip which adds electrical interaction with the cells to the previously utilized mechanical interaction. Unfortunately, direct long-term interaction for the microchip with the body is difficult as most of the materials used in microchips are either chemically reactive, toxic, or both, and must be hermetically sealed to maintain a degree of biocompatibility. This separation between the electrical elements of the biomedical device requires use of a transducer, an object which transforms the interaction between the body and a specific material, the analyte, into another signal which can interact with electronics. One popular transducer for both biosensors and electrical stimulation devices is the utilization of an extremely conductive material, otherwise known as an electrode.
Like every other material utilized in long term implantation, electrodes must be made of a non-corrosive, highly conductive material that does not cause adverse body reactions, is thromboresistant, and has good material durability and strength. Noble metals like gold, platinum, and iridium have been traditionally used in many electrically-active biomedical devices. Transmission electrodes that activate action potentials in electrically active cells, like the ones used in implantable heart pacemakers, have longevity in vivo, but these same electrodes experience many problems when miniaturized for smaller microelectrode array devices. This problem is most exemplified by the generation of Faradaic reactions at the surface of the electrode that produce harmful reactive species which interact with tissue near the electrode and lead to an inflammatory response. Faradic reactions are generated either due to the electrochemical interaction between the electrode and the electrolyte, but can also be dependent on the large charge injections required for cellular membrane depolarization which pass through a small geometrical surface area (i.e., high current density). The ideal electrode would not produce Faradaic reactions and have a large geometrical surface area to allow for large charge injection.
An example is the brain machine interface (BMI), which offers therapeutic options to relieve many individuals suffering from central nervous system (CNS) or peripheral nervous system (PNS) disabilities due to disease or trauma. The central component of the BMI system is the neuronal prosthetic which interacts with the body's electrophysiological signals. Implantable neuronal prosthetics have the ability to not only receive electrical signals directly from neurons or muscles, but they can deliver electrical signals to these same cells and provide a means for a closed loop BMI systems. These devices are unfortunately still regulated to experimental BMI systems due to a severe long term in vivo reliability issue. Device failure over time is thought to arise from lowered material biocompatibility which activates the immune response of the body, or failure can arise due to deterioration of the electrical interaction point due to Faradaic reactions caused by the high current densities needed for neuron action potential activation. The solution to this problem is to find materials that are physically and chemically resilient, biocompatible, and have great electrical properties.
Graphene is a two-dimensional (2D) monoatomic layer of graphite which has shown exceptional mechanical, optical, and electrical properties enabling it to perform a wide range of different applications. It is the basic building block for many popular carbon containing materials like the 0D "Bucky ball" C60, the popular 1D carbon nanotube, and if layered into a 3D structure, it becomes common graphite. Graphene was originally obtained via mechanical exfoliation of graphite, the so-called 'scotch tape method', which however yields graphene flakes of limited sizes. Many different methodologies like sheet extraction from graphene dispersions to epitaxial growth on semiconductors, silicon dioxide, and metals have been used to gain large area sheets of graphene. One interesting method utilizes the sublimation of silicon (Si) from the surface of silicon carbide (SiC), which has generated large scale monolayer and few-layer epitaxial graphene sheets.
Although graphene is an attractive material for the study of quantum electrodynamics, it presents an equal attraction for the generation of a new set of electronic and mechanical devices superior to Si.

Graphene electrodes on a planar cubic silicon carbide (3C-SiC) long term implantable neuronal prosthetic device