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A model of a vacuum thermionic refrigerator with external heat transfer is proposed. The general expressions for cooling load and coefficient of performance (COP) are derived using the combination of finite time thermodynamics and nonequilibrium thermodynamics. The optimum regions of cooling load and COP are obtained and the effect of the heat reservoir temperature on the optimal performance of the device is analyzed by detailed numerical examples. The effects of work function on the cooling load and COP performances of the thermionic device are also investigated. By comparing the results obtained herein with those using the traditional analysis without considering external heat transfer, it is shown that the present analysis is more practical for real vacuum thermionic devices. The results may provide guidelines for the design and application of practical thermionic refrigerators [ABSTRACT FROM AUTHOR]

A phase-locking model has been developed from circuit theory to qualitatively explain the various regimes observed in magnetron injection-locking experiments. The experiments utilize two continuous-wave oven magnetrons: one functions as an oscillator and the other as a driver. The model includes both magnetron-specific electronic conductance and frequency-pulling parameter. Both time and frequency domain solutions are developed from the model, allowing investigations into the growth and saturation as well as the frequency response of the output signal. This simplified model recovers qualitatively many of the phase-locking frequency characteristics observed in the experiments. [ABSTRACT FROM AUTHOR]

Magnetic pulse forming is high velocity forming technology, which requires the workpiece with better conductivity. However, high-strength steel with lower conductivity is difficult to deform by magnetic pulse forming. In this paper, AA1060 sheet was employed to drive DP600 sheet which was used to solve the forming problem of high-strength steel in magnetic pulse forming. Experimental tests and numerical method were used to investigate the deformation characteristic of DP600 sheet. Effects of drive sheet and discharge voltage for DP600 sheet deformation were analyzed. Forming height increases with increasing discharge voltage and optimal thickness of driver sheet is 2 mm. Forming profile and thickness of deformed DP600 sheet were provided. Distribution of magnetic field line and magnetic force were presented by numerical simulation. Higher magnetic flux density and magnetic force can be produced by 2 mm Al driver sheet. Deformation process, velocity, strain rate, and principal strain were investigated. During the driving process, DP600 sheet was accelerated and got higher velocity about 252 m/s with 2 mm driver sheet and C = 615 μF/U = 3.38 kV. Principal strain increases with discharge voltage increasing. And the varied trend can be described by quadratic equation. [ABSTRACT FROM AUTHOR]

Summary: This paper presents efficient and fast hardware implementations of the complete point multiplication on binary Edwards curves (BECs). The implementations are based on extremely fast complete differential addition and doubling formulas. These new complete differential addition formulas are performed for general and special cases of BECs with cost of 5M + 4S + 2D and 5M + 4S + 1D, respectively, where, M, S, and D denote the costs of a field multiplication, a field squaring and a field multiplication by a constant, respectively. In the general case of the BECs, proposed structures are implemented based on 3 and 1 pipelined digit‐serial Gaussian normal basis multipliers. In the design by 3 multipliers, computation of point addition and point doubling is performed concurrently. But in the second implementation for low‐cost design with low number of hardware resources, these computations are implemented by 1 multiplier. Also, in the special case of BECs, 2 structures are proposed for achieving the highest degree of parallelization and utilization of resources by using 3 and 2 field multipliers. Implementation results of the proposed architectures based on Virtex‐5 XC5VLX110, Virtex‐4 XC4VLX100, and Arria‐10 10AX115U4F45I3SG FPGAs for 2 fields F 2 163 and F 2 233 are achieved. The results show improvements in terms of execution time, area, and efficiency for the proposed structures compared with previous works. [ABSTRACT FROM AUTHOR]

The Einsteinian revolution, which began around 1905, was one of the most remarkable in the history of physics. It replaced Newtonian mechanics, which had been accepted as completely correct for nearly 200 years, by the special and general theories of relativity. It also eliminated the aether, which had dominated physics throughout the nineteenth century. This paper poses the question of why this momentous scientific revolution began. The suggested answer is in terms of the remarkable series of discoveries and inventions which occurred in the preceding decade (1895-1904) and which were the result of technological developments in instrumentation. The paper gives a survey of these inventions and discoveries, which include X-rays, radioactivity (radium and alpha, beta and gamma rays), the electron, wireless transmissions across the Atlantic and the patenting of the first thermionic valve. An attempt is then made to show that it was these developments, which gave rise to special relativity. [ABSTRACT FROM AUTHOR]

ICT and related electronic appliances consumed 4% of global electrical energy in 2007, growing to 4.7% in 2012, with projections of continued increase in coming decades. This is despite an average annual increase in energy efficiency of about 30% in ICT/electronics throughout the last 5 decades. Mainstream studies of energy-related rebound effects have yet to produce a conceptual framework that adequately encapsulates a unique feature of ICT/electronics: its tendency to induce changes in social practice and socio-technical structures. This study attempts to fill this gap. Surveying rebound effect literature, it builds on studies which explore ‘transformational’ change caused by energy efficiency increases. It identifies structural changes in business, education, the military and households caused by energy efficiency increases in ICT/electronics, which lead to a proliferation of ICT/electronic devices and consequently increased energy consumption. It shows the cause-and-effect logic between energy efficiency and energy consumption in ICT/electronics, and tentatively estimates rebound effects ranging between 115% and 161% in eight diverse empirical examples. The history of ICT/electronics shows that energy efficiency increases inevitably lead to increases in energy consumption, hence firm controls on CO 2 e emission allowances may offer the best hope of curbing energy consumption and CO 2 e emissions in this sector. [ABSTRACT FROM AUTHOR]

A traditional pulse generation circuit based on the pulse-forming-line (PFL) is implemented in a commercial 0.13 m digital CMOS technology. A meandered on-chip coplanar waveguide is used as the PFL, and CMOS transistor is used as switch in the Cadence Spectre simulation. The circuit sample is fabricated and tested. Pulses of ~170 ps durations and 120-200 mV amplitudes are obtained when the power supply is tuned from 1.2 V to 2 V. The results show that the traditional PFL based circuit can be implemented in standard CMOS technology for on-chip short pulse generation. Furthermore, the PFL circuits significantly extend the short pulse generation capabilities of CMOS technology. [ABSTRACT FROM AUTHOR]

A rigorous validation for the use of a set of linear time-invariant models as a surrogate in the design of controllers for uncertain nonlinear systems, which are invertible as one-to-one operators, such as used in the nonlinear quantitative feedback theory (NLQFT) design methodology has been given by Baños and Bailey. This paper presents a similar validation but weakens the requirement on the invertibility of the nonlinear plant by application of Kakutani's fixed-point theorem and an incremental gain constraint on the plant within its operational envelope. The set of linear time-invariant models to be used for design is shown to be an extension (termed here the linear time-invariant extension--LTIE) of the nonlinear plant restricted to the desired output operating space. A new non-parametric approach to the modelling of the LTIE is proposed which is based on Fourier transforms of the plant I/O data and which accordingly may be based solely on experimental testing without the need for an explicit parametric plant model. This new approach thus extends the application of robust linear controller design methods (including those of NLQFT) to nonlinear plants with set-valued (multi-valued) inverses such as those containing backlash and also to plants for which explicit parametric models are difficult to obtain. The method is illustrated by application of the nonparametric approach to an NLQFT tracking controller design for a mechanical backlashed servomechanism problem. [ABSTRACT FROM AUTHOR]

Permanent magnetic actuators (PMAs) have been widely used in medium-voltage vacuum circuit breakers (VCBs) due to their high reliability and controllability. However, a conventional bistable PMA cannot be adopted in power equipment for the transmission voltage level such as 126 kV VCBs directly because of its low-velocity characteristics. The objective of this paper is to propose a multimagnetic circuit PMA to satisfy the high-velocity requirements for 126 kV VCBs. The novel PMA is a bistable and axisymmetric structure, including holding and driving components whose magnetic circuits are separated. Air gaps are specifically designed in the magnetic circuits to improve the velocity performance of the novel PMA. Both static and dynamic characteristics of the novel PMA model have been calculated through finite-element software coupled with multi-body dynamics software. Furthermore, a prototype of the PMA has been developed according to the calculation results. The experimental results on the prototype have shown that the velocity characteristics of the PMA are able to meet the requirements of a 126 kV VCB and agree well with the simulation results. [ABSTRACT FROM PUBLISHER]

This paper studies the error exponent of block coding over an additive white Gaussian noise channel where a fraction (f) of the channel output symbols are revealed to the transmitter through noiseless feedback. If the code rate exceeds fC, where C is the channel capacity, then the probability of decoding error cannot decay faster than exponentially with block length. However, if the code rate is below fC, the error probability can decrease faster than exponentially with the block length, as with full feedback (f=1). This is achieved by combining a feedback code and a forward error control code, and jointly decoding them at the receiver. This scheme can attain higher reliability than rate splitting in which feedback and forward codes independently encode separate source messages. [ABSTRACT FROM AUTHOR]

Robotic surgery provides many benefits such as reduced invasiveness and increased dexterity. This comes at the cost of no direct contact between surgeon and patient. This physical separation prevents surgeons from performing direct haptic exploration of tissues and organs, imposing exclusive reliance on visual cues. Current technology is not yet able to both measure and reproduce a realistic and complete sense of touch (interaction force, temperature, roughness, etc.). In this paper, we put forward a concept based on multimodal feedback consisting of the integration of different kinds of visual and tactile cues with force feedback that can potentially improve both the surgeon's performance and the patient's safety. We present a cost-effective tactile display simulating a pulsating artery that has been integrated into a haptic work-station to combine both tactile and force-feedback information. Furthermore, we investigate the effect of different feedback types, including tactile and/or visual cues, on the performance of subjects carrying out two typical palpation tasks: (1) exploring a tissue to find a hidden artery and (2) identifying the orientation of a hidden artery. The results show that adding tactile feedback significantly reduces task completion time. Moreover, for high difficulty levels, subjects perform better with the feedback condition combining tactile and visual cues. As a matter of fact, the majority of the subjects in the study preferred this combined feedback because redundant feedback reassures subjects in their actions. Based on this work, we can infer that multimodal haptic feedback improves subjects' performance and confidence during exploratory procedures. [ABSTRACT FROM AUTHOR]

The transcutaneous energy transmission system (TETS) composed of a Class-E amplifier may operate at a state away from the optimum power transmission due to the load variation. By introducing the feedback-loop technique, the TETS can keep the optimum state with constant output voltage by adjusting the important design parameters, that is, the duty ratio and frequency of the driving signal and the supply voltage. The relations between these adjusted parameters and the load are investigated. The effectiveness of the feedback technique is validated through a design example with a variable load parameter. The experimental results show that the Class- E amplifier in the feedback loop can keep operating at the optimum state under the condition of up to 50 percent variation of the load value. [ABSTRACT FROM AUTHOR]

It is shown how sinusoidal voltage-controlled oscillators (VCO) providing linear tuning laws can be realised with current feedback op-amps (CFOA) in conjunction with analogue multipliers (AM) and eight such new VCO configurations are presented. The new VCOs offer several advantages compared to previously known VCOs realised with traditional voltage-mode op-amps in conjunction with FETs or AMs. The workability of the new propositions is demonstrated by experimental results based upon AD844 type CFOAs and AD534 type AMs. [ABSTRACT FROM AUTHOR]

Abstract: The electrical characteristics of Au/n-Si (100) Schottky rectifier have been studied in a wide irradiation fluence range using conventional current–voltage (I–V) and capacitance–voltage (C–V) measurements. The I–V characteristics showed an abnormal increase in forward current at low voltage. The device shows a bend in forward I–V and reverses bias C–V characteristics due to extra current, suggesting that there are two independent contributions to thermionic current, corresponding to two levels of the Schottky barrier. It is shown that the excess current at low voltage can be explained by taking into account the role of heavy ion irradiation induced defects at the metal semiconductor interface. [Copyright &y& Elsevier]

The aim of this work is to design a static feedback gain used to force a three-phase shunt active power filter to act as a current source capable of delivering the appropriate harmonics demanded by non-linear loads. This filter is connected in parallel to a three-phase power distribution system in order to keep the current supplied by the latter almost sinusoidal. The control design is performed using the H∞ suboptimal control theory based on linear matrix inequalities (LMIs), with both partial and full state feedback. Numerical simulations will be presented in order to investigate the advantages of the full state feedback structure over the partial state feedback one, and to compare the performances of the corresponding H∞ static control laws. [ABSTRACT FROM AUTHOR]

A fast-acting complex impedance measuring device for conducting investigations in pulse electrophysical experiments is described. The device features a high noise immunity. The working frequency of the measuring device varies from 20 to 80 MHz, and the time constant is <100 ns. [ABSTRACT FROM AUTHOR]

We describe an improved temporal analysis of products (TAP) reactor design whose main new features in comparison to the recent TAP-2 design of Gleaves et al. [Appl. Catal. A 160, 55 (1997)] are the use of a turbomolecular pump, piezoelectrically driven pulse valves, and a newly designed, differentially pumped gate valve. The gate valve allows fast and simple changes between high pressure operation, in which in situ catalyst treatment can be performed, and the analytic mode with a direct line-of-sight connection to the analysis chamber and the mass spectrometer. The heating system and pulse valves are located outside the vacuum chamber, resulting in a system that is easy to operate and modify. The high stability and reproducibility of the pulse intensity allows for direct, quantitative evaluation of single-pulse and multipulse experiments. The performance of the system is demonstrated using the CO oxidation over a Au/TiO2 catalyst as test reaction. [ABSTRACT FROM AUTHOR]

This paper describes a 150-400 MHz programmable clock multiplier which uses a recirculating DLL. The clock multiplier uses a sampling phase detector and employs chopping, autozeroing and various other circuit techniques to reduce static phase offset and crosstalk between the reference and the output clock. The DLL is implemented in 0.18-µm CMOS, consumes 16 mW of power, and achieves 1-5 ps RMS jitter and -70 dBc reference spur level. [ABSTRACT FROM AUTHOR]

A novel multiuser scheduling and feedback strategy for the multiple-input multiple-output (MIMO) downlink is proposed in this paper. It achieves multiuser diversity gain without substantial feedback requirements. The proposed strategy uses per-antenna scheduling at the base station, which maps each transmit antenna at the base station (equivalently, a spatial channel) to a user. Each user has a number of receive antennas that is greater than or equal to the number of transmit antennas at the base station. Zero-forcing receivers are deployed by each user to decode the transmitted data streams. In this system, the base station requires users' channel quality on each spatial channel for scheduling. An opportunistic feedback protocol is proposed to reduce the feedback requirements. The proposed protocol uses a contention channel that consists of a fixed number of feedback minislots to convey channel state information. Feedback control parameters including the channel quality threshold and the random access feedback probability are jointly adjusted to maximize the average throughput performance of this system. Multiple receive antennas at the base station are used on the feedback channel to allow decoding multiple feedback messages sent simultaneously by different users. This further reduces the bandwidth of the feedback channel. Iterative search algorithms are proposed to solve the optimization for selection of these parameters under both scenarios that the cumulative distribution functions of users are known or unknown to the base station. [ABSTRACT FROM AUTHOR]

The principal advantages of the sequentially fired pulse forming network (SFPFN) over its passive analog are its utility in both linear and nonlinear load applications. Operation of the SFPFN consists of charging multiple capacitor banks to different voltage levels and sequentially firing these banks into the load at appropriate times. The load characteristics and the desired pulse attributes determine the module charge voltage and sequential firing schedule. This paper describes the pulsed power system and computer control system design of a 750-kJ SFPFN. Typical experimental results in the case of a linear load are presented and compared with simulations, and pulse-shaping capabilities are demonstrated. Scaling considerations are discussed in the case of increasing the SFPFN energy capacity to 7.5 MJ. The SFPFN uses a computer-controlled field programmable gate array to initiate the trigger signal for each module's output switch. The use of a computer-controlled firing circuit provides an opportunity to incorporate real-time load monitoring and feedback to select the optimal firing times and durations based on dynamic load conditions. The incorporation of feedback during a pulse sequence also allows for the firing sequence to be halted in the event of a fault or other potentially harmful event. The charging controller features a computer monitoring and control system to allow a single power supply to charge multiple capacitor modules by an array of switching relays, even though each module may be charged to a different voltage. In linear load testing, the SFPFN provided a relatively constant current pulse to a resistive load. Pulse-shaping capabilities are demonstrated by varying the charge voltage of individual banks prior to a firing sequence. Future applications of the SFPFN include powering a helical launcher. [ABSTRACT FROM AUTHOR]

The article profiles electrical engineer William D. Coolidge, recipient of the Edison Medal given by the American Institute of Electrical Engineers. He was known for his contributions to incandescent electric lighting and X-ray arts. He adopted a suggestion to try using thermionic filaments of tungsten instead of the cold cathode emitters used in X-ray tubes. He became the associate director of General Electric Research Laboratory in 1928.

The plasma density distributions in the slit aperture of the extended rectangular hollow cathode of the source of a ribbon electron beam are investigated experimentally. It is found that a local maximum whose parameters are determined by the discharge current appears in the density distribution when the slot width is less than a certain threshold value. This maximum results in an inhomogeneous current density distribution in the beam. It is shown that the appearance of the local maximum in the plasma density is related to the overlapping of the ion sheaths in the slit aperture of the hollow cathode. [ABSTRACT FROM AUTHOR]

We have developed a thin, slim speaker unit with little magnetic leakage by employing a new kind of sandwich-type magnetic circuit. The main features are the high rigidity of the diaphragm due to the use of a multi-rib construction and a planar voice coil with the coil placed flat on the diaphragm. By controlling the mode of resonances in the directions along the long and short axes, a slim shape is maintained while achieving wideband characteristics. We demonstrate examples of applying this speaker to flat, thin TV sets. [ABSTRACT FROM AUTHOR]

This paper describes a 16 ⊗ 16 bit single-cycle 2's complement multiplier with a reconfigurable PLA control block fabricated in 90-nm dual-Vt CMOS technology, operating at 1 GHz, 9 mW (measured at 1.3 V, 50°C). Optimally tiled compressor tree architecture with radix-4 Booth encoding, arrival-profile aware completion adder and low clock power write-port flip-flop circuits enable a dense layout occupying 0.03 mm² while simultaneously achieving: 1) low compressor tree fan-outs and wiring complexity; 2) low active leakage power of 540 μW and high noise tolerance with all high-Vt usage; 3) ultra low standby-mode power of 75 μW and fast wake-up time of <1 cycle using PMOS sleep transistors; 4) scalable multiplier performance up to 1.5 GHz, 32 mW measured at 1.95 V, 50°C, and (v) low-voltage mode multiplier performance of 50 MHz, 79 μW measured at 570 mV, 50 °C. [ABSTRACT FROM AUTHOR]

We present two applications of a characteristic p analog of multiplier ideals, which is a generalization of the test ideal in the theory of tight closure. Namely, we give alternative proofs to Smith's result on base-point-freeness of adjoint bundles in characteristic p > 0 and results on uniform behavior of symbolic powers in a regular local ring due to Ein, Lazarsfeld and Smith, and Hochster and Huneke. [ABSTRACT FROM AUTHOR]

The load inductance, Ld, can be several times smaller than that of the pulsed power generator, L0, limiting the energy transfer efficiency. We define a relatively simple circuit modification, which improves the generator-to-load coupling, multiplying the load current in the case of interest, where L0>Ld. The suggested circuit modification operates similarly to an N:1 transformer and it can be designed to operate in vacuum with pulsed-power loads at high currents (many megaamperes). The current multiplier requires an additional volume having high self inductance, L, connected through convolutes to the generator and load. In its simplest configuration, N=2, a single convolute is required. The presented analysis shows that the efficiency of the proposed current multiplication scheme can theoretically exceed the values for a typical direct load-to-generator circuit. The modified hardware allows an increase of the load current by the factor of Id/Ig=NL/(L+Ld), where Ig represents the generator current and L can be easily made much greater than Ld either with or without the use of magnetic cores. The only uncertainties of this approach are potential convolute losses and the slight increase in load current rise time. Preliminary experimental tests were performed with a scaled down configuration which demonstrated current gain of 1.7 in the frequency range of interest and showed good agreement between analytically predicted and measured currents. The benefit of the scheme is also illustrated by simple circuit simulations for two types of potential applications requiring high power densities in vacuum: isentropic compression studies with Ld=constant loads, and imploding z-pinch research with dynamic [Ld(t)] loads. The proposed device is applicable for improving the characteristics of existing and future pulse power facilities. [ABSTRACT FROM AUTHOR]

Using the concept of loss compensation, novel broad-band monolithic microwave integrated circuits (MMICs), including an amplifier and an analog multiplier/mixer, with LC ladder matching networks in a commercial 035-μm SiGe BiCMOS technology are demonstrated for the first time. An HBT two-stage cascade single-stage distributed amplifier (2-CSSDA) using the modified loss-compensation technique is presented. It demonstrates a small-signal gain of better than 15 dB from dc to 28 GHz (gain-bandwidth product = 157 GHz) with a low power consumption of 48 mW and a miniature chip size of 0.63 mm2 including testing pads. The gain-bandwidth product of the modified loss-compensated CSSDA is improved approximately 68% compared with the conventional attenuation-compensation technique. The wide-band amplifier achieves a high gain-bandwidth product with the lowest power consumption and smallest chip size. The broad-band mixer designed using a Gilbert cell with the modified loss-compensation technique achieves a measured power conver- sion gain of 19 dB with a 3-dB bandwidth from 0.1 to 23 GHz, which is the highest gain-bandwidth product of operation among previously reported MMIC mixers. As an analog multiplier, the measured sensitivity is better than 3000 V/W from 0.1 to 25 GHz, and the measured low-frequency noise floor and corner frequency can be estimated to be 20 nV/sqrt(Hz) and 1.2 kHz, respectively. The mixer performance represents state-of-the-art result of the MMIC broad-band mixers using commercial silicon-based technologies. [ABSTRACT FROM AUTHOR]

This paper presents and analyses a method for synthesizing the feedback block of a 2-d.o.f. real PID regulator, referring to the widely used ISA structure and particularly well suited for autotuning. A rigorous stability, performance, robustness and consistency analysis is provided, extending some results of the previous literature. An objective criterion is devised for selecting the method's (single) design parameter based on the process model employed and an overestimate of the corresponding process/model mismatch. Both simulation and practical application examples are reported. [ABSTRACT FROM AUTHOR]

The question of which spectrally shaped dither signals are appropriate for use in quantizing systems, with and without noise shaping error feedback, or in recursive digital filters using dithered quantization at the output, is addressed. It is shown that dithers that are acceptable without feedback present may be unacceptable if feedback is introduced. In each case, certain classes of dither generators are shown to be appropriate for audio applications. [ABSTRACT FROM AUTHOR]

We introduce a generalized method for constructing subquadratic complexity multipliers for even characteristic field extensions. The construction is obtained by recursively extending short convolution algorithms and nesting them. To obtain the short convolution algorithms the Winograd short convolution algorithm is reintroduced and analyzed in the context of polynomial multiplication. We present a recursive construction technique that extends any d point multiplier into an n = dK point multiplier with area that is subquadratic and delay that is logarithmic in the bit-length it. We present a thorough analysis that establishes the exact space and time complexities of these multipliers. Using the recursive construction method, we obtain six new constructions, among which one turns out to be identical to the Karatsuba multiplier. All six algorithms have subquadratic space complexities and two of the algorithms have significantly better time complexities than the Karatsuba algorithm. [ABSTRACT FROM AUTHOR]

Measurement data (MD) converters with negative and positive feedback from series-connected aperiodic and pulse circuits are designed. Their static errors and correction for multiplicative and additive errors are studied. Stability of MD converters is investigated and a method of enhancing it by a proper choice of operation mode for the pulse circuit is described. Different variants of the structural circuit of the MD converter are described. Results of an experiment with a pilot MD converter are presented. [ABSTRACT FROM AUTHOR]

Recently, occurrences of chaos have been reported in many engineering systems and most of these occurrences are unfavorable phenomena which used to be controlled. This paper proposes two methods for the stabilization of arbitrary unstable periodic orbits embedded in chaos attractors existing in nonlinear discrete-time systems using nonlinear feedback. First, we propose a method based on a property of contraction mappings. Next, we propose another method using exact linearization via nonlinear feedback. In both methods, differentiability of the controlled systems is not required. Moreover, feedback need not be reconstructed in target periodic orbits. [ABSTRACT FROM AUTHOR]

This paper considers the large-scale discrete event system which is composed of multiple concurrently operating subsystems. The decentralized state feedback control is discussed for the case where the control specifications are given by predicates concerning the whole system. First, a necessary and sufficient condition is shown for a predicate which is obtained by a global state feedback to be obtained also by a decentralized state feedback. However, it should be noted that, in general, there exists more than one decentralized state feedback that can achieve the global predicate. From such a viewpoint, the maximally and minimally permissive decentralized feedbacks are defined and investigated. It is shown that there always exists the minimally permissive decentralized feedback, and its construction method is presented. Also, it is shown that, although the maximally permissive decentralized feedback does not, in general, exist, it can be obtained in the case that local state feedbacks are constructed according to a specified order. The construction method for that case is shown. [ABSTRACT FROM AUTHOR]

This paper describes the development and applications of a new generation of ‘vacuum tubes’ used primarily for ‘high-voltage modulator’ and ‘switch’ service. These tubes were developed to meet system needs that existing devices do not fill. Their prime features are reduced size and weight, rugged planar construction, low inductance, low capacitance, optimized high voltage performance, and ‘x-ray radiation shielding’. Circuits for several common applications will be shown. [ABSTRACT FROM AUTHOR]

This paper proposes a new construction method for 2-D IIR digital filters with all-pass subfilters as components. Recently, numerous studies have been made to construct digital filters by combining all-pass characteristics. This paper is based on the construction by a parallel connection of an all- pass subfilter and delay element, which can realize approximately the linear phase characteristic. First, the basic design for 1-D digital filters as well as its properties are described. Then the theory for the 1-D case is extended to the 2-D case, and a new construction method for 2-D digital filters with low-pass characteristics with circular symmetry is shown. The proposed method features the following. The phase characteristic is approximately linear in the passband. The filter can be realized with a smaller number of multipliers than in the traditional method. The coefficient sensitivity is low. [ABSTRACT FROM AUTHOR]

The modular feedback design is the following method. When a control specification in a discrete event system is given by conjunction and disjunction of a finite number of predicates, a feedback is designed for each predicate, and the whole feedback is constructed by product and sum of the component feedbacks. By this design method, the state feedback can easily be reconstructed when the control specification is modified. This paper considers the model proposed by Golaszewski and Ramadge, and we derive a condition under which the control invariance of the component predicates implies the control invariance of their conjunction and disjunction. Moreover, we derive a condition tinder which the unique existence of maximally and minimally permissive feedback for each component predicate implies that for the conjunction and disjunction. Finally, the derived result is applied to control of a manufacturing system. [ABSTRACT FROM AUTHOR]

The rise tint of the oscillation amplitude which is a problem in an ultralow-frequency oscillator is discussed for a three-phase CR oscillator. Four amplitud-stabilizing circuits are proposed and their dynamic characteristics are compared by simulations. The computation was based on the Runge-Kutta method. The analysis was applied to the three-phase ultralow-frequency switched-capacitor oscillator to confirm the operation. By means of the method for installing a positive feedback in each of the three-phase shifters, a rise tint of less than one-tenth period was obtained. Analog multipliers were used for the control of the feedback voltage gain and the oscillation amplitude detection. [ABSTRACT FROM AUTHOR]

Pulse dispersion due to conductor loss is studied. Design guidelines are provided for controlling the dispersion caused by pulse propagation on a lossy interconnection. The maximum R/ωL ratio arid interconnection length are given such that the additional delay caused by pulse dispersion is limited to within 10 percent of the line delay due to a lossless interconnection of the same length when it is terminated with ZL = √Lext/C, where Lext is the external inductance of the line. [ABSTRACT FROM AUTHOR]

An efficient multiplier has been designed using a polarization-encoded optical shadow casting scheme. The design algorithm far identifying the source patterns, input patterns, and output mask is also presented. [ABSTRACT FROM AUTHOR]

Presents information on a study which focused on the transient behavior of vacuum tubes in series. Details on experiments conducted; Methods used in carrying out the experiments; Conclusions of the study.

This paper presents a construction of a robust fault-tolerant multiplier aiming at high safety, where the output does not differ much from the normal value, even if a temporary fault is produced in the operation unit. For this purpose, a robust fault- tolerant divider circuit by a Fixed positive constant is devised, which is called divider. The multiplier is constructed by arranging such dividers in parallel. The proposed robust fault-tolerant multiplier is based on the distributed coding, where the input! output information Is always represented by the number o pulses. Consequently, a system-down is not produced even if more than one temporary error is generated, which is different from the majority redundant circuit. Another feature is that there is no hardware core, such as the majority- decision circuit for the output signal selection, and a temporary error does not produce a system-down. [ABSTRACT FROM AUTHOR]