摘要:

This paper presents the development of an improved iterative technique for solving static finite‐element algebraic equations on microcomputers. The method is based on a projection of the residuals using a partial Choleski decomposition of the global stiffness matrix. A line search is employed to accelerate the convergence of the algorithm. A two‐step method based on different partial decomposition is developed and implemented. Efficient implementation of this technique on a small computer with no out‐of‐core storage is presented. The sample physical problems solved demonstrate the proposed method to be of advantage in microcomputer applications where computer storage is a

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1989.tb00011.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Techniques for automating the design of highways are examined. It is accepted design practice to reduce the straight‐line parts of the horizontal alignment of a designed center line as much as possible. This can be accomplished manually by using clothoid templates. This article describes the use of spiral splines that behave in a manner such that the horizontal alignment may be automatically designed as a composition of clothoid segments. The resulting methods are suitable for microcomputer implementatio

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1989.tb00012.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

This paper presents a Frontal solver for structural dynamic analysis on IBM PC/XT or PC/ AT microcomputers. The program is coded in C. Subspace iteration is used for solving the eigenvalue problem. Various aspects on the design and the implementation of the program in a C environment are discussed in detail. A full listing of the program modules and a driver program are also provided.

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1989.tb00013.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Microcomputers are currently used to solve linear problems in structural dynamics. However, realistic engineering applications require a large amount of processing operations such that computer execution time and storage requirements can become critical. It is shown in this paper that the solution of large three‐dimensional linear dynamic problems using microcomputers is best accomplished by working with a reduced system of equilibrium equations expressed in generalized coordinates derived from a new load‐dependent subspace Ritz‐transformation method instead of the classical eigensolution procedure. Numerical applications on the microcomputer earthquake response analysis of a three‐dimensional model of nearly 2000 dynamic degrees of freedom is used to illustrate the relative efficiency of the proposed solution algorithm as compared to the subspace iteration

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1989.tb00014.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Practical solution of the structural analysis problem in a parallel processing environment is investigated through the use of the notion of cheap concurrency and the concept of threads. A thread is a lightweight process or independent instructions executing agent capable of concurrent execution with other threads. Portions of a structural analysis code implemented in C have been parallelized employing the Encore Parallel Threads on an Encore Multimax multiprocessor computer. The issues of racing condition, synchronization, and mapping are considered and discussed. Two synchronization mechanisms, semaphores and monitors, have been employed and compared. Two different mapping strategies have been implemented and studied. Results are reported on the effect of amount and frequency of shared memory access on the speed‐up, the overhead time required for creating threads, and comparison of overall computational time performance using two space truss examples. An overall efficiency of 90–95% was achieved for 11 process

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1989.tb00015.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Current advances in microcomputer technology provide the tools to use interactive graphics in the development of efficient computer programs. The use of computer graphics facilitates the definition of complicated engineering models, and permits a clear display of the results. In this paper, an educational microcomputer software package, TRUSS‐AD, is described to demonstrate the effectiveness of applying interactive computer graphics in solving structural engineering design problems. TRUSS‐AD allows the user to: (1) define a truss geometry and loading conditions graphically; (2) analyze and design the truss in an interactive mode; and (3) display all results in a concise and clear graphical representation. The stiffness method is used in the analysis process. The design can be performed by using either the “Load and Resistance Factor Design” or the “Allowable Stress Design” methods. The software is written using thebasiclanguage for IBM or compatible persona

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1989.tb00016.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1989.tb00017.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY