Computer Aided Design of Feeders for Castings

This paper describes a software module, contained within a design-for-casting package, which aids the user in designing efficient feeding systems for castings. The user can choose a shape suitable for a particular casting condition from a file containing a variety of feeder head types. The feeder heads are placed relative to the casting in positions appropriate to hot spots identified by a ‘heat centre’ module within the package. The number and size of heads are chosen with the aid of built-in rules that aid the user. The module provides a rationale for people, both skilled and unskilled, who have to design for casting. The validity of the design rules and guidelines within the module is demonstrated by casting three widely different shapes with and without feeders.

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Knowledge-Based Computer-Aided Design System for Ingot Casting Processes

2nd International Conference on Design Theory and Methodology ◽

10.1115/detc1990-0140 ◽

1990 ◽

Author(s):

R. Viswanath ◽

Yogesh Jaluria

Keyword(s):

Heat Transfer ◽

Decision Making ◽

Computer Aided Design ◽

Heat Transfer Analysis ◽

Manufacturing Processes ◽

Ingot Casting ◽

Design Rules ◽

Knowledge Based ◽

Computer Aided ◽

Aided Design

Abstract Thermal manufacturing processes are typically those in which a material is subjected to a temporal thermal cycle like casting, extrusion and heat treatment of metals and plastics. The complexity of the design process for all these systems stems from the need to simulate complicated heat transfer, fluid flow and phase change phenomena and couple the results with the design rules and knowledge available on the manufacturing processes to obtain satisfactory designs. In this regard, the ability of expert systems to use heuristic reasoning has proved to be a powerful tool in the computer-aided-design of thermal manufacturing systems. In this paper, the salient features of a knowledge-based system developed for the design of ingot casting process has been outlined. A Prolog based decision making front-end is interfaced with a Fortran based computational engine for rapid design. The results from the heat transfer analysis obtained from the computational module, are coupled to the evaluation module, which checks for satisfaction of the design criteria and violation of the design constraints. The decision making module uses a set of design rules to manipulate the variables until the design specifications are satisfied. Modularity and flexibility are maintained using an object-oriented format. Several interesting design acceleration features like learning from simple mathematical models and design extraction from previous designs are illustrated. The main features of this knowledge-based tool and the savings in time resulting from using these special features are discussed in detail.

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Taxonomy of Discretely Manufactured Products for Making Ergonomic Considerations

Proceedings of the Human Factors and Ergonomics Society Annual Meeting ◽

10.1177/154193120504901804 ◽

2005 ◽

Vol 49 (18) ◽

pp. 1696-1700

Author(s):

Adaeze Nwaigwe ◽

Bart Nnaji

Keyword(s):

Potential Application ◽

Computer Aided Design ◽

Group Technology ◽

Ergonomic Design ◽

Design Rules ◽

Washing Machines ◽

Manufactured Products ◽

Computer Aided ◽

Aided Design ◽

User Actions

There are hundreds of thousands of everyday products — from screws and pens to washing machines. Each of these products has certain ergonomic rules that are necessary for designing them for safety and comfort. To efficiently and concisely capture ergonomic design rules relevant to the great variety of products, this paper applied group technology in categorizing discrete manufactured products for ergonomic design. The method of classification was on the basis of user-actions on such products. Ten classes were determined and corresponding ergonomic rules pertinent to each class were stipulated. The taxonomy showed its robustness by accurately determining ergonomic rules relevant to the design of several products. The potential application of this work is to computer-aided design.

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Моделирование переходных процессов в полупроводниковых приборах на основе 4H-SiC (учет неполной ионизации легирующих примесей в модуле ATLAS программного пакета SILVACO TCAD)

Физика и техника полупроводников ◽

10.21883/ftp.2019.03.47295.9014 ◽

2019 ◽

Vol 53 (3) ◽

pp. 407

Author(s):

П.А. Иванов ◽

А.С. Потапов ◽

Т.П. Самсонова

Keyword(s):

Physical Model ◽

Dynamic Characteristics ◽

Computer Aided Design ◽

Room Temperature ◽

Software Module ◽

Capacitive Element ◽

Computer Aided ◽

Simulation Results ◽

Rc Circuit ◽

Aided Design

AbstractTransient process in a resistor–capacitor (RC) circuit with a reverse-biased 4 H -SiC p – n diode as the capacitive element is simulated. Simulation is performed with the ATLAS software module from the SILVACO TCAD system for technology computer-aided design (TCAD). An alternative way, to that in ATLAS, to set the parameters of doping impurities partly ionized in 4 H -SiC at room temperature is suggested. (The INCOMPLETE physical model available in the ATLAS module, which describes the incomplete ionization of doping impurities in semiconductors, is unsuitable for simulating the dynamic characteristics of devices.) The simulation results are discussed in relation to previously obtained experimental results.

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