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This paper discusses some factors which have to be taken into account in the design of high power transistors. An effect of great importance is the reduction of emitter bias caused by transverse current flow in the base region. This effect is examined in some detail and the results of the discussion are applied to the design of improved transistor types. Finally, a short discussion of thermal stability and mechanical design is given.

The single common-emiter transistor amplifier fed from a resistive source exhibits a minimum noise figure, when the source resistance has an optimum value. A generalized amplifier is next shown that is fed from a complex source impedance and containing a single common-emitter transistor in the first stage. It is assumed that noise in succeeding stages is negligible. Various feedback paths to either the base or emitter of the first transistor are shown, and an effective shunt input resistor with thermal noise and an effective emitter degeneration resistor with thernlal noise are given. If the signal source is purely resistive, analysis of the circuit shows that a minimum noise figure is obtainable with an optimum source resistance. If the source is a complex impedance, the quantity of interest is the signal-to-noise ratio (SNR) at the output of the amplifier. This quantity will in general be dependent on the signal frequency chosen, and on the gain characteristics of the entire amplifier. An expression for SNR in the circuit is given. Again, the result is independent of any feedback, except insofar as the feedback affects the gain characteristic. It is to be emphasized that the criteria for best noise performance are in no way connected with the criteria for maximum power transfer from the source.

Over 1 watt of continuous ultraviolet output has been obtained from an argon ion laser in the 3500-3700Å range. This paper describes the discharge tube structure used and the operating characteristics of high-power ultraviolet laser transitions in argon and other noble gas ions. Operation at new wavelengths as well as CW operation of transitions previously observed only in pulsed operation are reported. Measurements of the dependence of spontaneous emission intensity from different ionization states on current and pressure are related to the excitation mechanisms for visible and uv ion lasers. The technique of population modulation by intracavity interruption has been used to study processes in the throat and uniform bore regions of ion laser discharges. The results of these studies are described. Problems encountered in the CW operation of ion laser discharge tubes at current densities above 1000Å/cm^2 are described.

The development of coherent optical sources, producing usable amounts of power, has provided a stimulus for communications research. Coherent sources in the form of lasers and parametric oscillators are available at wavelengths which span the entire optical spectrum. This paper reviews the state of the art of coherent optical sources with major emphasis on the most highly developed sources.

The development of coherent optical sources, producing usable amounts of power, has provided a stimulus for communications research. Coherent sources in the form of lasers and parametric oscillators are available at wavelengths which span the entire optical spectrum. This paper reviews the state of the art of coherent optical sources with major emphasis on the most highly developed sources.

only given, substantially as follows. The properties derived by G. Polya and E.C. Titchmarsh for band-limited deterministic signals are extended to bandlimited processes. It is shown that the number of zeros /b n/(/b T/) (complex and real) of the process with a magnitude

The typical noble gas ion laser plasma consists of a high-current-density glow discharge in a noble gas, in the presence of a magnetic field. Typical CW plasma conditions are current densities of 100 to 2000 A/cm^2, tube diameters of 1 to 10 mm, filling pressures of 0.1 to 1.0 torr, and an axial magnetic field of the order of 1000 G. Under these conditions the typical fractional ionization is about 2 percent and the electron temperature between 2 and 4 eV. Pulsed ion lasers typically use higher current densities and lower operating pressures. This paper discusses the properties of ion laser plasmas, in terms of both their external discharge parameters and their internal ion and excited state densities. The effect these properties have on laser operation is explained. Many interesting plasma effects, which are important in ion lasers, are given attention. Among these are discharge nonuniformity near tube constrictions, extremely high ion radial drift velocities, wall losses intermediate between ambipolar diffusion and free fall, gas pumping effects, and radiation trapping. The current status of ion laser technology is briefly reviewed.

The typical noble gas ion laser plasma consists of a high-current-density glow discharge in a noble gas, in the presence of a magnetic field. Typical CW plasma conditions are current densities of 100 to 2000 A/cm^2, tube diameters of 1 to 10 mm, filling pressures of 0.1 to 1.0 torr, and an axial magnetic field of the order of 1000 G. Under these conditions the typical fractional ionization is about 2 percent and the electron temperature between 2 and 4 eV. Pulsed ion lasers typically use higher current densities and lower operating pressures. This paper discusses the properties of ion laser plasmas, in terms of both their external discharge parameters and their internal ion and excited state densities. The effect these properties have on laser operation is explained. Many interesting plasma effects, which are important in ion lasers, are given attention. Among these are discharge nonuniformity near tube constrictions, extremely high ion radial drift velocities, wall losses intermediate between ambipolar diffusion and free fall, gas pumping effects, and radiation trapping. The current status of ion laser technology is briefly reviewed.

Previous theoretical work on the operation of charge-coupled devices has been rather qualitative. These studies emphasize one of a number of factors which can influence the charge-transfer process, for example, nonlinear diffusion and fringing fields. However, none of these studies take account of all the factors in a realistic way.

In the above paper [1], Varshamov considers discrete channels with q inputs and q outputs, q being an arbitrary integer.

In the above paper [1], Varshamov considers discrete channels with q inputs and q outputs, q being an arbitrary integer.

An investigation of the dependence of slot-line wavelength upon a thin layer of adhesive between metal and substrate is described. It is shown that the presence of adhesive will cause an increase in wavelength when the dielectric constant of the adhesive is less than that of the substrate. Experimental results are presented which show this dependence for a variety of surfaces and adhesives. A perturbation expression is given which permits correction of experimental data for comparison with theory when this effect occurs.

Although this is the fifth conference in the series, it is only the third that has included a session on Analysis Techniques. The session was introduced into the program in the belief that this area deserved greater attention and would provide a cornerstone to which application oriented sessions could be referred. In its two previous years, the Analysis session has been well received, and this year four out of the six papers present developments or extensions of work reported in the previous years.

A detailed numerical simulation of the charge-transfer process in buried-channel CCDs will be presented. The limitations on the device performance due to incomplete free charge transfer, device parameters and clocking waveforms will be discussed.

LSI has provided machine designers a medium of unprecedented power and versatility. The potential of this technology has been doubling every year and promises to continue for another factor of 1000. It is inevitable that such potential will be used to achieve ever more powerful machine organizations and will, in the long run, totally change our basic concepts of machine structure and function. To date, however, the microprocessors which have been implemented are of a very conventional type. This trend poses several fundamental questions.

The potentials of airborne and spacecraft borne imaging radars in earth resources applications are reviewed and discussed. The areas specifically addressed are: oceanography, coastal regions studies, glaciology, polar ice studies, geology, geomorphology and agriculture. The paper also addresses the main areas of emphasis for the next ten years.

Examines the modification of calorific power that can be expected to take place if organising separate collection of papers, glass and plastics in a semi-rural area of 112000 inhabitants around Wavre at the South outskirts of Brussel., Anglais

A unique circuit design using conventional MOS technology has been found to yield a sequential read-only analog memory which can generate the x- and y-axis deflection voltages for the stroke-by-stroke synthesis of alphanumeric characters.

Published abstract NR 20140805

The paper discusses the classification problem using discriminant function solution that minimizes the probability of classification error. Learning algorithms using window function technique are presented. The algorithm convergence rates are computed and a particular strategy is proposed. Experimental results are performed and the efficiency of the proposed algorithms is proven. A comparison with the mean-square-error algorithm is also presented., Anglais

Session 2 covers a broad spectrum of topics, ranging from circuit analysis methods through new circuit configurations to system applications, and also a component testing technique. In the first paper, Hayner et al. introduce a new pulse-width-modulated dc-to-dc boost converter, the Venable converter, in which current is fed continuously to the output capacitor, thereby alleviating the filtering requirements. In addition, the converter has high efficiency and transfer function properties that do not depend upon the duty ratio. Rostad et al, in the second paper,describe the application of the Venable converter to a series of satellite TWT power processors.

In this paper we investigate the homogeneous dielectric slab waveguide in the case of complex dielectric constants. A method for calculating the field distribution in a dielectric waveguide with an arbitrary symmetrical variation in the refractive index is developed, and some of the results are presented. The results are applied to the GaAs laser. It is fonud that the guiding mechanism is a combination of gain guiding and index antiguiding. Based on the calculations an explanation of the kinks on the light current characteristics is suggested.

In this paper we investigate the homogeneous dielectric slab waveguide in the case of complex dielectric constants. A method for calculating the field distribution in a dielectric waveguide with an arbitrary symmetrical variation in the refractive index is developed, and some of the results are presented. The results are applied to the GaAs laser. It is fonud that the guiding mechanism is a combination of gain guiding and index antiguiding. Based on the calculations an explanation of the kinks on the light current characteristics is suggested.

In recent years, a number of techniques have been developed for the design of linear, constant gain feedback controllers for systems with imprecisely Known parameters. In this paper, several of these techniques are compared in the context of the design of a lateral autopilot for a rudderless remotely piloted vehicle with uncertain aerodynamic coefficients. Properties of the design techniques on which the comparison is based include closed-loop system performance at nominal and off-nominal parameter values, computational cost and complexity, ease of implementation in a real system, and generality of the parameter uncertainty which can be dealt with.

In this paper an alternative method for solving multi objective optimization problems is presented. We are especially concerned with bridging a gap between procedures for obtaining the Pareto-optimal solutions and the “best compromised” preferred solution for the decisionmaker. First, the main concepts of the utility approach are briefly reviewed from the point of view of multiobjective systems analysis, and some shortages of this approach are examined. Second, a new method which we call the nested Lagrangian multiplier method (or NLM method) is introduced and compared with precedent devices for the utility approach The theoretical background is also scrutinized. Third, the use of the NLM method for environmental systems management in the greater Osaka area is demonstrated, providing an example of dynamic application of this method. Finally, it is recalled that utilization of a mathematical optimization method for integrated plannings would simultaneously provide optimal solutions for allocation as well as evaluation problems, based on duality of mathematical programming. A stress is placed on the utilization of dual optimal solutions as a base of evaluation factors. Copyright

In this paper an alternative method for solving multi objective optimization problems is presented. We are especially concerned with bridging a gap between procedures for obtaining the Pareto-optimal solutions and the “best compromised” preferred solution for the decisionmaker. First, the main concepts of the utility approach are briefly reviewed from the point of view of multiobjective systems analysis, and some shortages of this approach are examined. Second, a new method which we call the nested Lagrangian multiplier method (or NLM method) is introduced and compared with precedent devices for the utility approach The theoretical background is also scrutinized. Third, the use of the NLM method for environmental systems management in the greater Osaka area is demonstrated, providing an example of dynamic application of this method. Finally, it is recalled that utilization of a mathematical optimization method for integrated plannings would simultaneously provide optimal solutions for allocation as well as evaluation problems, based on duality of mathematical programming. A stress is placed on the utilization of dual optimal solutions as a base of evaluation factors. Copyright

This paper presents a new approach to the frequency-domain analysis of multiloop linear feed-back systems. The properties of the return difference equation are examined using the concepts of singular values, singular vectors and the spectral norm of a matrix. A number of new tools for multiloop systems are developed which are analogous to those for scalar Nyquist and Bode analysis. These provide a generalization of the scalar frequency-domain notions such as gain, bandwidth, stability margins and M-circles, and provide considerable insight into system robustness.

This paper describes an adjustment procedure for observer-based linear control systems which asymptotically achieves the same loop transfer functions (and hence the same relative stability, robustness, and disturbance rejection properties) as full-state feedback control implementations.

The branch filters in a digital polyphase network can be designed either as FIR filters by decomposing the impulse response of an FIR low-pass prototype filter, or as o r d i i IIR filters by the synthesis method of Bellanger. The use of all-pass networks has hitherto been considered unfeasible because of the associated computational difficulties involved in the design of filter banks with many branches. The purpose of this paper is to demonstrate that it is indeed possible to design the branch filters as all-pass-low-pass sections without the need of a prototype filter. Moreover, these sections can be realized as wave digital filters, which give improved properties over the other designs with respect to hardware requirements, group delay, sensitivity, dynamics and limit cycles. Examples, including the design of the practically important 60-channel filter bank for the transmultiplexer, are given

In a recent paper, Pierce studied the problems of communicating at optical frequencies using photon-counting techniques, and concluded that "at low temperatures we encounter insuperable problems of encoding long before we approach [channel capacity]." In this paper it is shown that even assuming a noiseless model for photon communication for which capacity (measured in nats/photon) is infinite, it is unlikely that a signaling efficiency of even 10 nats/photon could be achieved practically. On the positive side, it is shown that pulse-position modulation plus Reed-Solomon coding yields practical results in the range of 2 to 3 nats/photon.

In a recent paper, Pierce studied the problems of communicating at optical frequencies using photon-counting techniques, and concluded that "at low temperatures we encounter insuperable problems of encoding long before we approach [channel capacity]." In this paper it is shown that even assuming a noiseless model for photon communication for which capacity (measured in nats/photon) is infinite, it is unlikely that a signaling efficiency of even 10 nats/photon could be achieved practically. On the positive side, it is shown that pulse-position modulation plus Reed-Solomon coding yields practical results in the range of 2 to 3 nats/photon.

The nonlinear optimization problem and statistical design problem can both be formulated as a region search problem. In this paper, we present a stochastic optimization process, suitable for optimizing functions of a certain measure over generalized regions in R". Conditions for an optimal process are discussed, and examples of a wide range of different optimization problems are given. These include the optimization of constrained, discontinuous and random functions in both discrete and continuous variable space. Design centering and tolerancing of large size system subject to environmental disturbances are also treated.

This paper will discuss a unified digital image distribution and processing system linking various digital image sources through a broadband local area network and a comnon image format. Ultimately, the system allows for viewing and processing of all images produced within the complex, and for viewing stations at any number of convenient locations. The physical handling of storage media at image sources, can be totally eliminated. Complete archiving, file maintenance and large scale processing capabilities are provided by a central file server. This paper presents a concrete proposal for an initial system which has a central archiving facility for permanently storing and selectively viewing computed tomography (CT), nuclear medicine (NM) and ultrasound (US) images. The system proposed can then be slowly expanded to include all the digital images produced by the radiology the department, and ultimately to include all the images by digitizing those produced in an analog fashion., QC 20111208

The paper gives a results about general identifiability conditions expressed in terms of the properties of the probabilistic measures, corresponding, to the observable processes, when the parameters value is fixed. The application of these results to special cases permit to get the identifiability conditions which can be checked before the experiment or observation process starts.

The paper gives a results about general identifiability conditions expressed in terms of the properties of the probabilistic measures, corresponding, to the observable processes, when the parameters value is fixed. The application of these results to special cases permit to get the identifiability conditions which can be checked before the experiment or observation process starts.

This paper introduces a nonconservative measure of performance for linear feedback systems in the face of structured uncertainty. This measure is based on a new matrix function, which we call the Structured Singular Value.

Imaging systems in microwaves, millimeter and submillimeter wave applications employ printed circuit antenna elements. The effect of substrate properties is analyzed in this paper by both reciprocity theorem as well as integral equation approach for infinitesimally short as well as finite length dipole and slot elements. Radiation efficiency and substrate surface wave guidance is studied for practical substrate materials as GaAs, Silicon, Quartz and Duroid.

Imaging systems in microwaves, millimeter and submillimeter wave applications employ printed circuit antenna elements. The effect of substrate properties is analyzed in this paper by both reciprocity theorem as well as integral equation approach for infinitesimally short as well as finite length dipole and slot elements. Radiation efficiency and substrate surface wave guidance is studied for practical substrate materials as GaAs, Silicon, Quartz and Duroid.

Imaging systems in microwaves, millimeter and submillimeter wave applications employ printed circuit antenna elements. The effect of substrate properties is analyzed in this paper by both reciprocity theorem as well as integral equation approach for infinitesimally short as well as finite length dipole and slot elements. Radiation efficiency and substrate surface wave guidance is studied for practical substrate materials as GaAs, Silicon, Quartz and Duroid.

QC 20111214

A necessary and sufficient condition is derived which must be satisfied by the plant steady state gain matrix of a linear time invariant system in order for an integral controller to exist for which the closed loop system is unconditionally stable. Based on this theorem the robustness of integral control systems is analyzed, i.e. the family of plants is defined which are stable when controlled with the same integral controller. Conditions for actuator/sensor failure tolerance of systems with integral control are also given. Finally, parallels are drawn between the results of this paper and the bifurcation theory of nonlinear systems.

Coplanar transmission lines lose energy to surface waves when the propagation constant of the surface-wave mode exceeds that of the transmission line. This happens when the substrate thickness is an appreciable fraction of a wavelength. The losses should become important in integrated circuits at near-millimeter wavelengths because it is hard to make the substrate thickness small compared to a wavelength. In this paper we have developed a theory based on reciprocity for predicting these losses. We also utilized the quasi-static approximation method to derive expressions for propagation constants and line impedances. Experimental measurements were made for the surface-wave losses in the two strip line, the two slot line and the three wire line, and the results obtained were consistent with the theory.

This paper outlines a general framework for analysis and synthesis of linear control systems and reports on a new solution to a very general L_∞/H_∞ optimal control problem.

This paper outlines methods for computing the key factorizations necessary to solve general H2 and H∞ linear optimal control problems.

The transient analysis of electromagnetic fields has shown its utility not only in clarifying the variation of the fields in time but also in gaining information on mechanisms by which the distributions of an electromagnetic field at the stationary state are bronght about. We have recently proposed a new numerical method for the transient analysis in three-dimensioual space by formulating the equivalent circuit based on Maxwell's equation by Bergeron's method. The resultant nodal equatiou is uniquely formulated in the equivalent circuit for both the electric field and the magnetic field. In this paper, we deal with the stripline which should be analyzed essentially in three-dimensionaf space because of its structure, The time variation of the electric and magnetic field of the stripline having a comer is analyzed and the remarkable changing of distribution of the field is presented as a parameter of time and of conditions imposed by the corner stucture.

The transient analysis of electromagnetic fields has shown its utility not only in clarifying the variation of the fields in time but also in gaining information on mechanisms by which the distributions of an electromagnetic field at the stationary state are bronght about. We have recently proposed a new numerical method for the transient analysis in three-dimensioual space by formulating the equivalent circuit based on Maxwell's equation by Bergeron's method. The resultant nodal equatiou is uniquely formulated in the equivalent circuit for both the electric field and the magnetic field. In this paper, we deal with the stripline which should be analyzed essentially in three-dimensionaf space because of its structure, The time variation of the electric and magnetic field of the stripline having a comer is analyzed and the remarkable changing of distribution of the field is presented as a parameter of time and of conditions imposed by the corner stucture.

The transient analysis of electromagnetic fields has shown its utility not only in clarifying the variation of the fields in time but also in gaining information on mechanisms by which the distributions of an electromagnetic field at the stationary state are bronght about. We have recently proposed a new numerical method for the transient analysis in three-dimensioual space by formulating the equivalent circuit based on Maxwell's equation by Bergeron's method. The resultant nodal equatiou is uniquely formulated in the equivalent circuit for both the electric field and the magnetic field. In this paper, we deal with the stripline which should be analyzed essentially in three-dimensionaf space because of its structure, The time variation of the electric and magnetic field of the stripline having a comer is analyzed and the remarkable changing of distribution of the field is presented as a parameter of time and of conditions imposed by the corner stucture.