Imaging techniques for cable network structures

Imaging techniques are presented for developing interactive computer display of cable network structures on a microcomputer such as the IBM PS/2®. These structures create surfaces formed by an orthogonal mesh of cables and are primarily loaded normal to the surface. A three-dimensional perspective representation of network structures is developed for fast drawing of cable structures on microcomputers.     

System for Monitoring the Spatial Energy Distribution of Laser Radiation Utilizing an IBM-Type Personal Computer

The results are presented of the development of set of basic circuits providing for the thermostatting of the heat-sensitive layer of a multielement receiver utilizing VO₂, the readout and measurement of information in the plane of a multielement laser radiation receiver, and the interfacing of the receiver with an IBM PC/AT personal computer.     

Quantum Algorithms and Experiment Implementations Based on IBM Q

With the rapid development of quantum theory and technology in recent years, especially the emergence of some quantum cloud computing platforms, more and more researchers are not satisfied with the theoretical derivation and simulation verification of quantum computation (especially quantum algorithms), experimental verification on real quantum devices has become a new trend. In this paper, three representative quantum algorithms, namely Deutsch-Jozsa, Grover, and Shor algorithms, are briefly depicted, and then their implementation circuits are presented, respectively. We program these circuits on python with QISKit to connect the remote real quantum devices (i.e., ibmqx4, ibmqx5) on IBM Q to verify these algorithms. The experimental results not only show the feasibility of these algorithms, but also serve to evaluate the functionality of these devices.     

Analysis, design, and implementation of an AC bridge for impedancemeasurements

The paper reviews the digital AC bridge. A more accurate and thorough analysis of the bridge is presented. Based on the analysis a simple adaptive algorithm is proposed in order to ensure fast conversion. In addition, a new design of the bridge, based on the TMS 320C25, is given. The system is implemented with the Dalanco Spry model 25 DSP board, on a software system designed whereby an IBM PC host computer provides control of the bridge. Experimental results are presented     

Data storage gets to the point

Could a system that is basically mechanical, albeit micromechanical, compete with electronic and magnetic devices for storing large volumes of data? Surprisingly, recent research suggests that the answer may be yes. Stranger still, the concept being investigated by IBM and others is not too far removed from that of the phonograph and record player, the once familiar system used for writing and retrieving data to and from revolving disks. But the scale of the once familiar pick-up needle compared with what is now proposed is as an ocean compared with a drop.In the new ultra-compact system for storing digital data developed by IBM researchers, patterns on the surface of a material are traced by points so fine that the impression left by one of them would be one fifty-thousandth the size of the full stop at the end of this sentence. Using technology first developed as the atomic force microscope (AFM) to trace topography down to the scale of individual atoms and molecules can, say IBM researchers, enable data to be stored at densities as high as 1 Tb/in² — a density ten times higher than today’s most advanced disk drives.     

Development of an algorithm for the calculation of the scattering properties of agglomerates

A new, improved, and more efficient algorithm for calculation of the scattering, extinction, and absorption characteristics of agglomerates consisting of Rayleigh-size primary particles is presented. The computer code is based on a new formulation of the light scattering for such agglomerates and is more than 10 times faster than the codes based on previous formulations. The computational times required by the old and the new algorithms, run on VAX 7000, IBM 3090, and UNIX RS6000 mainframe computers, are compared for different agglomerate configurations, such as straight chains, clusters, and randomly branched chains. A distributed-parallel-computing scheme was used to run the new algorithm on four UNIX RS6000 processors concurrently, resulting in computational times 47 times faster than required for the calculations. Furthermore, the robustness and convenience of the algorithm are assessed.     

IBM PC-Based IEEE-488 Bus Controller

This paper describes the design of a low-cost IEEE-488 multifunction bus controller board for the IBM Personal Computer (PC). The hardware interconnections of the bus controller chip with the IEEE-488 bus and the IBM PC bus are highlighted. In addition to the IEEE-488 control functions, the board is augmented with the two extra features of programmable interval timer and programmable digital input/output.. A software package is written with over 30 macro commands. The user can utilize these macro commands to implement most common IEEE-488 control functions. An example is given to configure and implement a multimeter as a programmable ohmmeter.     

Multi machining output—multi independent variable turning research by response surface methodology

A finish turning case is presented where an increase in tool Life was obtained without sacrificing surface finish. This was obtained by developing mathematical models for tool life and surface roughness in terms of the cutting speed, feed and depth of cut. Their contours were obtained utilizing PL 1 language and an IBM 360/50 computer, then the contours were superimposed in order to select the proper combination of cutting conditions.     

Direct numerical solution of three-dimensional equations containing elliptic operators

A direct three-dimensional elliptic solver is presented for application in a wide class of numerical methods for solving partial differential equations in physics and engineering. The derived algorithm and FORTRAN code implement Buzbee, Golub and Nielson's proposed extension of Buneman's Cyclic-Reduction Poisson solver to three dimensions. Both a ‘most direct’ cyclic reduction and a revised method (to eliminate roundoff error difficulties) are derived. Tests on an IBM 360/67 computer, using various optional combinations of subroutines, showed significant differences in accuracy and computing time, with the optimum subroutine combination depending on mesh size.     

Thermophysical properties of refrigerant R134a

Experimental results of measurements of the thermodynamic and transport properties of refrigerant R134a are presented for the temperature range 240–400 K and pressures up to 89 bar. The thermal properties of the saturated refrigerant were also determined. The results from this study showed that the dependence of viscosity on temperature near the critical region was nonlinear. This observation shows that errors resulting from using previous literature data for design purposes could vary from about 1.5% at 251 K to 30% at 343 K. A computer (IBM PC) was used to obtain empirical relationships for evaluating the thermophysical properties of R134a based on various sets of independent variables.     

Numerical prediction of the temperature distribution in the initial region of a two-dimensional turbulent film cooling configuration

The velocity field of a semi-contained turbulent jet, as constructed by Abramovich, is used to arrive at the temperature distributions in the initial region of a turbulent flow film cooling situation taking into account both the development of the jet boundary layer and the wall boundary layer. After suitable profiles of eddy thermal conductivity are established, a finite difference form of the thermal energy equation is derived, shown to be unconditionally stable, and solved numerically with the aid of an IBM System 360 computer to yield the temperature distributions. Wieghardt's parameter for collapsing the temperature profiles onto a single curve in film cooling situations, when suitably modified, also collapse the analytical results to essentially a single curve even as near as 2·7 slot heights from the injection point, thus verifying the temperature similarity in film cooling which has been experimentally observed even very near the injection point. Results in graphical form are presented which allows one to construct the actual temperature profile for a fairly wide range of the relevant parameters.     

A modification of the rule of mixture in estimating strengths of a Composite

Strengths of a composite when determined by actual tests shows a lower value than those obtained through theoretical estimation by applying the simple rule of mixtures. This discrepancy has been attributed largely to the presence of defects in the composite like debonding, porosities, cracks etc. To establish a design criteria to a more practically closer strength values an empirical formulae is presented. The formulae accounts for defect level upto 30%. The results were obtained through computational facilities using IBM (360/44) Computer. The drop in strength with increasing defect level is shown to occur and the effect is more predominant when defects are more in fibres than in matrix.     

Development of a scalable finite element solution to the Navier–Stokes equations

A scalable numerical model to solve the unsteady incompressible Navier–Stokes equations is developed using the Galerkin finite element method. The coupled equations are decoupled by the fractional-step method and the systems of equations are inverted by the Krylov subspace iterations. The data structure makes use of a domain decomposition of which each processor stores the parameters in its subdomain, while the linear equations solvers and matrices constructions are parallelized by a data parallel approach. The accuracy of the model is tested by modeling laminar flow inside a two-dimensional square lid-driven cavity for Reynolds numbers at 1,000 as well as three-dimensional turbulent plane and wavy Couette flow and heat transfer at high Reynolds numbers. The parallel performance of the code is assessed by measuring the CPU time taken on an IBM SP2 supercomputer. The speed up factor and parallel efficiency show a satisfactory computational performance.The authors wish to acknowledge Mr. W. K. Kwan of The University of Hong Kong for his help in using the IBM SP2 supercomputer.     

Least-squares solution of incompressible navier-stokes equations with the p-version of finite elements

A p-version of the least-squares finite element method, based on the velocity-pressure-vorticity formulation, is developed for solving steady-state incompressible viscous flow problems. The resulting system of symmetric and positive definite linear equations can be solved satisfactorily with the conjugate gradient method. In conjunction with the use of rapid operator application which avoids the formation of both element and global matrices, it is possible to achieve a highly compact and efficient solution scheme for the incompressible Navier-Stokes equations. Numerical results are presented for two-dimensional flow over a backward-facing step. The effectiveness of simple outflow boundary conditions is also demonstrated.This work was performed within the Department of Scientific Computing at IBM Kingston, New York     

具有可调增益的模糊—PID电液主动控制悬架

针对车辆悬架受不平路面激励作用下的振动,进行电液主动隔振研究,在分析PID和模糊控制方法的基础上,对车辆悬架系统的单自由度电液模拟装置进行了理论和实验研究,提出增益自动跟踪和变系数的模糊－PID控制算法,根据输入信号偏差的大小分别采用模糊或PID控制,通过微型计算机与MCS－98单片联机调试控制,悬架振动的控制效果得到提高,从2.875Hz到7Hz的低频范围内取得了优于被动控制的减振效果,为主动隔振技术在车辆减振实时控制中的应用提供了理论根据和实验基础。     

Investigation of point defect clusters in silicon using parallel molecular dynamics

A parallel molecular dynamics algorithm is presented for computingconfigurations of relatively large defects in crystalline silicon, as modelledby the Stillinger–Weber (SW) three-body interatomic potential. Thealgorithm is based on a partitioning of physical space among the N processorswith atoms migrating freely between the partitions. Implementation on aneight-processor IBM SP2 computer shows the increased efficiency withsimulation size expected because of the increased computational load perprocessor relative to communication overhead. The parallel efficiency reached70% for 21 952 atoms. Calculations are presented for the thermodynamics offormation of interstitial and vacancy clusters containing up to seven pointdefects. The clusters were relaxed within a host lattice of about 3000 siliconatoms subjected to periodic boundary conditions. Free energies of formationfor temperatures 500 K T 1600 K were computed using thermodynamicintegration. Computed equilibrium distributions for these clusters show ashift to the larger species at lower temperatures, as expected. The SWpotential predicts greater driving forces for interstitial aggregation thanvacancy aggregation across the entire temperature range. Model calculationsfor a large vacancy cluster are also presented to demonstrate the utility ofthe algorithm for exploring very large defects in silicon.     

Complex Optimization of Processes of Heat Exchange in Gas‐Firing Installations with Utilization of Heat

Results of complex experimental investigations of the processes of combustion and combined heat exchange with separation of radiative and convective components of boilers with utilization of secondary energy resources are presented. The complex optimization is conducted by solving a system of partial differential equations on EC, CM, and IBM computers. For the purpose of controlling the combustion and heatexchange processes automatically, the calculated dependences are given and charts of regimes are composed.