摘要:

This article is the second part of a two‐part article concerned with observing cracks on the pavement surface with very specialized microcomputer equipment mounted in a van type vehicle moving at road speeds. As one would imagine, the computing speed required to do the job is very high. In fact, to adequately handle this particular application, three camera systems, each with its own Motorola 68020 microprocessor, are required to work in parallel as the 12‐foot lane width is observed. In the first part of this article, an overview of the following technical requirements was presented [5]: 1) sensor data rate requirements, 2) hardware and software approaches, 3) pavement rating procedures, 4) system block diagram, and 5) real‐time computer algorithms.This article will extend and update previous pavement monitoring concepts while looking at the microprocessor requirements of moving a huge amount of processed data through the system. In addition, a host microprocessor (a Motorola 68010) will be responsible for system housekeeping and formatting all of the processed data for future use. Some introductory comments about the pavement monitoring system appear again for conti

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1986.tb00117.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

An interactive microcomputer‐based graphics preprocessor has been developed for computer‐aided design and drafting of plane frame structures. The graphics preprocessor has been developed in Advanced BASIC version 3.0 on an IBM Personal Computer. The preprocessor allows various manipulations of the frame structure such as zooming, panning, shrinking, expanding, node labeling, and element labeling. The flow between the graphics display and the data input is very easy and allows the user to enter new frame data, visually check it, and edit the data quic

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1986.tb00118.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

By assuming incompressible beams and columns in a multistory building frame, the frame may assume either a primary state equal to its underformed shape or a buckling mode when it is subjected to a set of primary axial forces that constitute the bifurcation loading. This article describes the theory and algorithm for a computer program by which the buckling load factor for a set of proportionate primary axial forces and the shape of the buckling mode may be obtained. It is shown that the buckling load factor thus obtained can be used to produce and effective length ratio for every column so that the Euler load of a pin‐ended column with this effective length is identical to the actual buckling load of that column in the multistory building fram

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1986.tb00119.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

A mixed, isoparametric finite element model for analysis of two‐dimensional, steady, incompressible Newtonian flows for a microcomputer has been developed. An ad hoc mixed variational principle, in terms of vorticity ω and streamline φ functions, has been used in the finite element formulation. The six‐node, isoparametric element has been employed in the computer program VISFLOW‐2D which uses the newton‐Raphson method to perform the nonlinear analysis. Computed ω and φ functions over a given domain are then used by the computer program PRESS‐2D, to calculate the pressure distribution. The unsymmetric frontal solver is used to solve the linearized equations in ω‐φ formulation and the symmetric frontal solver in the pressure formulation. A postprocessor has also been developed to plot the contours for ω, φ, and p, called CONT. This program splits each deformed or undeformed six‐node, isoparametric element into 16 three‐node triangular elements and computes the nodal values for the resulting elements before a linear interpolation is employed for plotting a contour. The procedure for analysis of steady, two‐dimensional, incompressible viscous flow was then used to solve the problem of flow around a cy

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1986.tb00120.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

CADD software and other large, highly interactive, complex programs must keep track of many complex relationships and perform the correct operations with both speed and precision based on these relationships, which are often seemingly in conflict. Computers can evaluate only one relationship at a time and the relationships must be evaluated in a specified order that can vary greatly depending on the outcome of each test. Consequently, writing and debugging a program that will perform correctly under a wide variety of inputs can be a frustrating process that at times can seem to produce two “bugs” for each one that is corrected. Tree structures can be employed to maintain a dynamic diagram of the program structure as it is being created. Graph structures, which are closely associated with tree structures, can be employed to simplify the task of developing and implementing the correct program logic and to identify many of the design logic errors at an early stage.This article describes the use of tree and graph structures to diagram program structure and logic for an educational CADD package that was written by the aut

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1986.tb00121.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Many programs have been and are currently being developed in which the input files or associated data bases must be produced independently of the main program. This article describes two programs which are used to develop an interactive, menu‐driven system of input prompts which is then used to create and maintain information files for other programs. The two program system provides an easy method to develop well‐structured, interactive input programs without the high development costs required to write original code. Graphics can be developed for any input screen and a command language can be specified for data output. Two examples are provided to present an overview of the sys

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1986.tb00122.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

This article presents a method and the results of an innovative self‐paced introduction to steel design (according to the Canadian standard CAN3‐576. 1M84) for students by describing the use of state‐of‐the‐art spreadsheets (or calcpads) with microcomputers. Spreadsheets are flexible, high‐level programming languages with which it is possible not only to program the display and calculation of formulas on a screen, but also to add explanatory text to the programs. A textbook has been developed, consisting of a set of templates, which can be modified, reduced, expanded, and refined according to the requirements of the user. A good academic background in structural analysis and a basic understanding of the particular spreadsheets are necessary. Using a spreadsheet as the basis for a design text has many advantages, the most obvious being the direct hands‐on experience the user will receive. Formulas should exist as tools to be applied directly instead of being only read and memorized. Text lines can be deleted or added to satisfy the needs of the user. Self‐paced involvement of the reader and clarity of the material are the foundations of the book's approach. When used correctly this text should become a working design tool rather than a dust collector

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1986.tb00123.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1986.tb00124.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1986.tb00125.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1986.tb00126.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY