Showing papers on "Domain (software engineering) published in 1970"

Contribution to numerical methods for calculation of complex dielectric permittivities

Abstract: A numerical method is described for computing complex dielectric permittivities by the von Hippel-Roberts method, using two samples of the same material and different size. In the process, the Newton-Raphson method is applied to the complex domain

Analytical theory of stable domains in high-doped Gunn diodes

Abstract: The form, amplitude and width of the stable domain are determined analytically for the case of high doping level (n0 > 5.0×1015cm?3).

A Domain Optimization Technique For EllipticBoundary Value Problems

Abstract: A numerical analysis technique is presented for solving optimization problems of geometrical domains in which elliptic boundary value problems are defined. Domain variation is formulated with a one-to-one mapping and its infinitesimal variation with a speed field as advocated by Zolesio. * The sensitivity functions, which we call the shape gradient functions, of domain variation are derived using the Lagrange multiplier method or the adjoint method. 3 By applying the gradient method in functional space* with the shape gradient functions, we propose to analyze an optimal speed field as a displacement of a pseudo-elastic problem that is defined on the design domain and loaded with pseudo-distributed external force, or traction, in proportion to the shape gradient function. This technique is called the traction method because of the procedure used. Numerical results for several linear elastic problems and flow field problems are given.

Integrated magneto-resistive sensing of bubble domains

Abstract: An integrated magneto-resistive sensor for detection of magnetic bubble domains. The sensor is located on the chip in which the bubble domains propagate and can be an integral part of the propagation circuitry. Any material exhibiting a magneto-resistive effect can be used, and permalloy is a preferred material. The sensing element can be made very small, and has a length which is usually about equal to a bubble domain diameter.

Magnetic domain logic circuit

Abstract: A multiple input magnetic domain OR circuit is described. The circuit is defined in a sheet of material in which single wall domains can be moved by changing magnetic pole patterns in a magnetically soft overlay. The overlay includes a common element which serves as a terminus for a number of domain shift registers. The element is structured to accept only a single domain for providing an output.

Ozone Modelling Over A Large City By Using A Mesoscale Eulerian Model: Madrid Case Study

Abstract: An Air Quality Model has been applied over the mesoscale urban area of Madrid (Spain). The Model is composed on different modules: a mesoscale meteorological module REMEST which solves the Navier-Stokes equation system over the Madrid domain. This model is running under the non-hydrostatic option and is the main code of the system. The model solves the prognostic equations by using an Eulerian approach and integrated an eulerian transport equation which is solved simultaneously. The meteorological module provides the wind speed, direction, temperature and humidity on a three dimensional domain at very short time steps (a few seconds). The model uses a 14 different landuse types which are obtained by using the REMO module which uses the information provided by the LANDUSE satellite image over the area with 30 m spatial resolution. The model transport the emitted pollutants into the domain and deposit them over the domain. The emission module EMIMA takes into account the point, line and area emissions over the area. Special importance is given to the biogenic emissions which are obtained by using the satellite landuse classification for caducous, perenneal and mixed terrain. The emission module considers the EPA and CORINAIR emission factors and is 250x250 m spatial resolution and 1 hour temporal resolution. The deposition module DEPO uses the resistance approach Transactions on Ecology and the Environment vol 10, © 1996 WIT Press, www.witpress.com, ISSN 1743-3541

Switching properties of bulk-effect digital devices

Abstract: The required trigger-pulse width and height for triggering a dipole domain in n-GaAs bulk devices were obtained analytically. Further switching properties of the three-terminal Gunn-effect digital devices have been made clear experimentally.

DIRECT OBSERVATION OF SINGLE‐DOMAIN SrTiO3

Abstract: A single‐domain SrTiO3 crystal is obtained by stressing along the [110] direction at 2°K and is observed optically for the first time. Domain structure under [001] stress is also examined. The importance of understanding the domain structure is discussed.

Domain wall structure in BaTiO3 during switching

Abstract: The increase in the complex permittivity during switching is calculated from a two-dimensional model of residual nuclei, assuming that domain walls possess a pyramidal step structure. The resulting formulae are compared with previous experimental data on BaTiO3 and with corresponding formulae from the same model with smooth walls. It is shown that the real part of the permittivity during switching is very sensitive to the presence of steps on moving domain walls and that there is an indication that in BaTiO3 such step structure actually exists.

A Semi-quantitative Physics Compiler

Abstract: Incomplete information is present in many engineering domains, hindering traditional and non—traditional simulation techniques. This paper describes SQPC (semi—quantitative physics compiler), an implemented approach to modelling and simulation that can predict the behavior of incompletely specified systems, such as those that arise in the water control domain. SQPC is the first system that unifies compositional modeling techniques with semi—quantitative representations. We describe SQPC’s foundations, QS1M and QPC, and how it extends them. We demonstrate SQPC using an example from the water supply domain.

Pengembangan Instrumen Evaluasi Domain Afektif

Abstract: To carry out evaluation comprehensively, we need appropriate instrument that suitable with domain that being evaluated. Evaluation instrument development with test has been conducted by experts. These instruments were only suitable to measure cognitive domain and part of psychomotor domain. To measure affective domain, we need to develop non-test evaluation instrument (alternative test). The development of this instrument tends to more difficult and complicated compare with instrument test evaluation instrument. Therefore, it does necessitate a through study to derive and elaborate affective domain to specific aspect to develop valid and reliable instrument.

Photographic tracking of artificial satellites

Abstract: A review of the development of photographic tracking techniques in different countries during the recent 5–6 yr is given. Main results of scientific investigations based on observations with Baker-Nunn cameras are considered. New large Soviet, English, French, German cameras are described. Important international projects on photographic tracking for satellite geodesy are reviewed. Main directions of research in this domain are discussed.

Domain propagation circuit

Abstract: An autonomous scanning circuit is realized by an arrangement of magnetically soft elements on the surface of a material in which single wall domains can be moved. Information representative of the conditions of a set of lines is stored in a domain register and compared with that of a previous scan period similarly stored. The expected one of two significant outputs from any given line is controlled by a unique domain circuit which remembers the next preceding output associated with that line.

Response Of Corrugated Steel Walls Due ToPressure Loads

Abstract: Recent work on response of corrugated steel walls subjected to uniform pressure loads is described. Tests are conducted on open corrugated steel panels using a water pressure test facility. Results are compared to numerical simulations in the quasi-static and dynamic domain. Some parametric studies are performed on the numerical models.

Extension of the lumped bulk device model to incorporate the process of domain dissolution

Abstract: A lumped model capable of representing domain nucleation, modulation, and quenching in n-GaAs has previously been reported. In the present paper an algorithm is proposed which successfully describes the process of domain dissolution. An analytical description of the mechanisms involved is achieved by characterizing the shape of a stable domain and by postulating the existence of an "apparent" domain which maintains the stable-domain shape while passing across an ideal anode boundary. The actual domain is then treated as that portion of the apparent domain remaining within the device. It is shown that during the dissolution process the apparent domain undergoes a growth mechanism due to the rise in device current. A complete mathematical description of the phenomena is subsequently incorporated into the original lumped model and simulated with the digital program BULKSIM. Device studies with the extended model have produced results exhibiting exceptional agreement with a distributed model simulated by the program BULK-D.

Automatic frequency-domain synthesis of multiloop control systems

Abstract: A computerized algorithm to facilitate the automatic synthesis of time-invarian t linear compensation for highly complex multiloop control systems is discussed. Performed in the frequency domain to attain desired open-loop frequency response characteristics, the algorithm is applicable equally to continuous-ti me systems in the S domain and sampled data systems in the W or Z domains. It is executed by a digital computer program, AUTO, which uses a gradient-search algorithm to select the coefficients of multiloop feedback compensation transfer functions. These coefficients provide an open-loop frequency response, optimum in the sense that its deviation from the one desired is minimal in the weighted leastsquares sense. The selection of a method for incrementing compensation parameters that alleviates "ridge following" convergence problems is discussed, as are the geometric properties of the least-squares cost function itself. Examples of cost function geometries are presented to provide insight into their nature.