The purpose of the present note is to provide a necessary and sufficient condition in order that strongly connected group-matrix type automata, whose orders are prime, may be regular. Further, as an applications, a problem concerning factor automata of a strongly connected automaton will be discussed.

This paper investigates problems associated with relaxation oscillation and output powers in homogeneously broadened four-level lasers having nonuniform population inversion and photon densities along the laser axis. The rate equation for the population and photon number of four-level lasers has been solved with considering the diffusion of excited states. Numerical solution shows that the energy migration between lattice sites significantly increases the frequency and damping constant of the relaxation oscillations together with the obtainable power from the spatially hole-burned lasers.

The electron density profile in the lower ionosphere was determined from the right and left handed circular polarized wave fields of the 40 KHz ground based signal observed by means of a rocket borne receiver. The determination of the electron density from 70 Km up to 100 Km was made under the condition for the values calculated by the full wave analysis to agree with the observed values.

Let J{1, 2, , n} be a set of jobs. Each job j can be processed on one of the m identical machines in one unit time, and has ready and due times. It is shown that the problem of finding an optimal schedule minimizing the sum of costs associated with jobs j, which are monotone functions of completion time of j, can be reduced to the assignment problem with 0(n) vertices; hence it can be solved in 0(n3) steps. As important special cases, this cost includes the weighted number of late jobs, the weighted tardiness, and the weighted flow-time. In addition, it is shown that the problem has an 0(n log n) algorithm if the objective is to minimize the (unweighted) number of late jobs. This problem is critical for having an efficient algorithm in the sense that generalizing it in various directions easily results in NP-complete problems. As an example, it is shown that it becomes NP-complete if precedence constraints are imposed.

This short paper treats some decision problems for Petri Nets and shows that the problems of the safeness, the reachability and the proper termination are NP-complete for Petri Nets in which each transition fires at most once.

Single axial mode oscillation in Integrated Twin-Guide AlGaAs laser fabricated by sputter-etching was observed by current injection pumping at room temperature, as predicted by theory.

Phase-matched film thickness are studied precisely for SHG in a nonlinear quartz-glass waveguide. The glass film waveguide deposited upon the surface of quartz suffers non-uniform stress due to the thermal expansion. This effect generates an anisotropic property in the film. Taking this anisotropy of the glass film into account, the observed film thickness for phase-matched condition results in good agreement with the theory.

A simple but enough accurate approximate formula is derived which gives the maximum power density of an FM wave modulated by a multi-channel telephony signal with a medium modulation index. This formula may be used by an administration who intends to establish communication system and shall send the information of the maximum power density at the input of the antenna to the International Frequency Registration Board in accordance with the Radio Regulations.

Using a tilted electric field (TEF) soft-landing collector, one of the authors has achieved an efficiency improvement of a TWT from 11.8 percent to 43.0 percent. However, the TEF collector requires a uniform magnetic field covering the entire collector space, and hence, a heavy magnet or electromagnet, which is far from practical in high-power tubes. This paper proposes the periodic magnetic field (PMF) soft-landing collector, which is a periodic field version of the TEF collector. It requires much lighter magnets than a TEF collector does. The principle, design theory, preliminary low-perveance experiment, and a relevant computer simulation are presented. Finally experiments with a medium-power UHF TWT equipped with a PMF collector are described.

EPISC (ETL's pattern information computing systems) is a computer system developed at ETL(Electrotechnical Laboratory) for pattern information research in the national project PIPS (Pattern Information Processing System) inaugurated in 1971, and is intended to be an original guide of PIPS Prototype the target of the Project. It has been implemented toward an in-house computer network, and is a star structured computer complex in which main and sub-computers communicate through high speed channels. For computer communication in EPICS, two levels of protocol are provided. Low level protocol is carried out by a newly developed hardware Computer Communication Controller and a resident module controlling it. High level protocol provides system services for an interface between user processes and EPICS control system. Those functions include remote job entry, file control and processes synchronization and are carried out by a non-resident module. Described are what kinds of high level protocol are well used for computer communication and that protocol sequences are reduced to five simple patterns observed as everyday occurrences in EPICS. Usage patterns of high level protocol sequences depend on experiment environments among work groups rather than on their research field.

A method for analyzing the input- and parameter-sensitivities of a broad class of nonlinear continuous systems with nonlinear feedback couplings is proposed. This method is carried out first by formulating the problems in the form of nonlinear integral equations, and then evaluating the solutions by applying fixed point theorems in the appropriate Banach spaces. The actual analysis in this paper is accomplished for the entire function type of nonlinear integral equations, making use of Banach's contraction operator principle, Schauder's fixed point theorem for completely continuous operators and the Leray-Schauder rotation concept of completely continuous vector fields. These procedures can be regarded as systematic and simple even for practical analysis of complicated systems.

A method of realizing a gyrator is presented. In this circuit, we can easily adjust the Y-parameters of the gyrator, Y11, Y12, Y21 and Y22, independently.A simple application of the gyrator to all-pass network is also given.

This paper describes the new type Solion Triode whose electrode gap is controlled by the electrodeposited (or electrodissolved) metal on (or from) one electrode of the two.

Lasing modes of the TJS-lasers (transverse-junction-stripe lasers) have been examined. Typical near and far field patterns show the fundamental transverse mode both in the x and y directions. From these patterns, the refractive index difference between the active region and the p-GaAs region is estimated to be about 0.2%, and that between the active region and the n-GaAs region to be 0.5-1%. Using these values, it is shown that only the fundamental transverse mode can propagate in the active region. The lasing spectra show a nearly single longitudinal mode operation in a wide range of the input current. The transition behavior of the longitudinal mode has been examined experimentally, and it is suggested that the single mode operation is caused by a heavy doping profile in the active region.

Finite automata, regarded as sequence transducers or encoders, are good models for analyzing characteristics of transmission codes. From such a stand point, some properties of transmission codes have been examined and some results obtained. First, the necessary and sufficient condition for a transmission code to have power spectral null at frequency f(h/k)fr is obtained, where h and k are relatively prime integers and fr is the pulse repetition frequency. It would be the most general result in the problem of power spectral nulls, although the special case where h/k0/1 is already known. Such a code is inherently modulating and, therefore, matches specific requirements in transmission system design. Second, it has been shown that spectral transformation is possible only by restricting inputs appropriately. In particular, it is illustrated that various transmission codes with dc-component can be made dc-component free by appropriately restricting inputs.

This letter presents the measuring method for obtaining the baseband swept-frequency response of multimode optical fibers. With the description of the measuring system, examples of fiber characteristics are given. The SNR and frequency resolution of the method are briefly discussed in comparison with the pulse broadning methods.

A new type of edge-guided mode (E. G. Mode) isolator is proposed, which has the following desirable characteristics: (a) high isolation (more than 40 dB with 1dB insertion loss), (b) simple structure without additional lossy materials, and (c) considerably broad band (40% relative bandwidth). Moreover, a new type of E. G. mode circulator for which the scattering matrix is of the non-cyclic from is also proposed.

This letter presents formulae by means of which AM and PM noise in mutually synchronized oscillators with asymmetrical locking forces can be estimated directly from parameters of the oscillators system. In particular, coupling phase dependence of PM noise conservation rates is studied in detail.

A phase measurable optical heterodyne interferometer which is capable for measuring both the modulus r12(0) and the phase ψ12(0)arg{r12(0)} of the spatial coherence function r12(0) without the need of the optically stringent requirement for the equality of the path-lengths in the two arms of the interferometer is established. An extended formulation for the intensity correlation function of optical fields is also presented in relation to the theory of the interferometer. The experimental verifications are presented and are compared with the results obtained from other interferometric systems.

Estimations on power-delay product as a figure of merit of transferred-electron devices are made for GaAs, InP and Ga0.5In0.5Sb, from a digital device point of view, taking account of the temperature rise. It is shown by comparison of these figures of merit that Ga0.5In0.5Sb is the most promising material for a high speed digital device.