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As most existing computer‐aided design systems do not provide part feature information which is essential for process planning, automatic part feature recognition systems serve as an important link between Computer Aided Design (CAD) and Computer Aided Process Planning (CAPP). Attempts to provide a structural framework for understanding various issues related to part feature recognition. Reviews previous work in the field of part feature recognition and classifies known feature recognition systems for the sake of updating information and future research. Briefly introduces about 12 systems. Studies 31 systems and lists them in the Appendix based on 60 references. Comments on future research directions.

International competition is driving manufacturing executives to place an ever‐growing importance on the formulation of computer integrated manufacturing (CIM) strategies as part of their corporate plans. Structured analysis and design techniques, in particular IDEF (Integrated Computer Aided Manufacturing definition method), are becoming a vital tool in the analysis and implementation of such CIM strategies. This article positively demonstrates the technique and its ability to model the link between design and manufacture in a CIM environment. The approach relates interdependencies of planning for manufacture, design and process planning within a CIM strategy. In particular it establishes the position of computer aided process planning (CAPP) in CIM architecture and evaluates a CAPP package as a potential element of a CIM strategy. The application to which IDEFo, in particular, has been used clearly demonstrates its usefulness to manufacturers as a powerful aid to the development of detailed CIM strategies.

To develop a new method for computer‐based 3D construction of garment basic cut on a computer generated body model.

The method has been developed on an example of a 3D garment basic cut construction on a virtual body model, determining the position of characteristic 3D points necessary for computer‐based definition of 3D cutting pattern contour segments. Contour segments modelling, as well as the modelling of 3D cut surfaces has been done using the NURBS objects.

A 3D garment cut has been constructed, such that matches physical characteristics of the body in question and offers the necessary comfort of the cut. The surface of the 3D cut has been divided into individual 3D cutting patterns.

The method has been developed on an example of a 3D garment basic cut construction of a single paper of clothing. However, the same principles can be applied and developed for any garment basic cut.

The 3D garment cut constructed can be further transformed into a network of polygons. Introducing fabric physical‐chemical properties fabric drape can be simulated, aiming at more realistic visualisation and further assessment of the garment fit. The 3D cutting patterns developed can be, applying computer‐based application of the mathematical models, transformed into 2D cutting patterns.

As compared to the methods developed by some previous investigations, the newly developed method offers the construction of garment 3D cut on a computer‐generated body model, granting the necessary comfort of the cut, which also means garment fitted to individual body characteristics. The 3D cut constructed can also be used as a starting point to define 2D cutting patterns in the following step, which will be matched to the physical characteristics of the model body, in the same way as the initial 3D cut.

The weft-knitted two-side jacquard fabric has the characteristics of complicated design principle and hard technical design. The purpose of this paper is to realize the computer-aided design of weft-knitted two-side jacquard fabric, and provide a certain reference for the development of this type of fabric.

The weft-knitted two-side jacquard fabric is divided into weft-knitted two-side similar pattern jacquard fabric and weft-knitted two-side independent pattern jacquard fabric. In order to achieve the purpose of this study, firstly, the structural characteristic of weft-knitted two-side jacquard fabric is analyzed. Then, the design principle of weft-knitted two-side jacquard fabric is studied. Next, the technical model of weft-knitted two-side jacquard fabric is established. Finally, the CAD flow chart of weft-knitted two-side jacquard fabric is proposed to realize the rapid product development.

Based on the above method, through the development example of weft two-side similar pattern jacquard fabric and weft two-side independent pattern jacquard fabric, the computer-aided design of the weft two-side jacquard fabric is verified.

Because of limited research studies, three-dimensional computer-aided design of weft-knitted two-side jacquard fabric loop structure will be studied in the further research, and the technical design speed needs to be improved to meet the needs of large patterns and positioning patterns.

The computer-aided design of weft-knitted two-side jacquard fabric will offer a certain reference for product development, technical principles, performance research and computer simulation for the in-depth study of the fabric.

The computer-aided design of weft-knitted two-side jacquard fabric will simplify the fabric design process and improve the efficiency of new fabric development, and provide the industries a time-saving and cost-saving approach for new fabrics development.

The author analyzes the structural characteristic of the fabric by the physical fabric, summarizes design principle of the fabric through production process, uses mathematical methods to establish a three-dimensional technical model of the fabric, and proposes the CAD flow chart of weft-knitted two-side jacquard fabric, which has good theoretical significance and practice of weft-knitted two-side jacquard fabric.

The purpose of this paper is to derive the small-signal/canonical model derivation of the high-side active clamp forward converter (ACFC) with diode rectification for ideal and with resistive parasitics. It also covers the analysis of ACFC small-signal model with resistive parasitics using computer-aided modeling software Personal Computer Simulation Program with Integrated Circuit Emphasis (PSPICE) 16.6. The effects of variation of system parameters on the ACFC’s state transfer functions and operations have been highlighted in this paper.

The large-signal model and small-signal model of the ACFC with diode rectification has been derived using AC small-signal modeling approach.

The operating point of the converter changes with the consideration of resistive parasitics compared with the ideal case. The response obtained from the hardware matches with the time domain response of the averaged model and switch model developed in PSPICE.

This paper limits the study of ACFC small-signal behavior by using computer-aided design software PSPICE. The dead time of the converter is not considered because it is negligible when compared with the on and off time. The leakage inductance which plays a role in zero voltage switching of the ACFC switches is neglected in the analysis as it is very small compared to the magnetizing inductance. The switching losses are not considered in the modeling.

The mathematical computation of deriving the system transfer functions from canonical model is complex and time consuming.

The modeling with resistive parasitics improves the effectiveness of the equivalent model. Also, the analysis with computer-aided modeling software PSPICE gives reliable results in less time.

A software package is described that attempts to develop students' knowledge of Computer Aided Production Management (CAPM) systems and an awareness of the power of the computer to predict the future by iteratively simulating individual workshop operations. It demonstrates the techniques of CAPM by means of manual simulation. Students then operate and adjust a simple computer simulation model and compare it with the manual exercise. Both versions are described and compared. The CAPM system is presently installed on the ACT Sirius and the IBM personal microcomputers. It consists of a series of basic programs and data files in four modules. There is wide scope for using both versions in degree courses in mechanical and production engineering and production management.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming and powder metallurgy are briefly discussed. The range of applications of finite elements on the subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for the last five years, and more than 1100 references are listed.

This study aims to develop a specialized and economically feasible educational model using a combination of conventional approach and additive technology with a precision that proves to be sufficient for educational use. With the use of computer-aided design/computer-aided manufacturing models in educational stages, the possibility of infectious diseases transmission can be significantly reduced.

The proposed process involves the planning and development of specialized anatomical three-dimensional (3D) models and associated structures using omnipresent additive technologies. A short survey was conducted among dental students about their knowledge of applying additive technologies in dental medicine and their desire to implement such technologies into existing curricula.

The results revealed how an educational 3D model can be developed by optimizing the mesh parameters to reduce the total number of elements while maintaining the quality of the geometric structure. The survey results demonstrated that the willingness to adapt to new technologies is increasing (p < 0.001) among students with a higher level of education. A series of recent studies have indicated that the lack of knowledge and the current skill gap remain the most significant barriers to the wider adoption of additive manufacturing.

An economically feasible, realistic anatomical educational model in the field of dental medicine was established. Additive technology is a key pillar of new specialized-knowledge digital skills for the enhancement of dental training.

The novelty of this study is the introduction of a 3D technology for promoting an economically feasible model, without compromising the quality of dental education.

The representation of Heterogeneous Object (HO) is divided into two categories: Data model (DM) and material evaluation paradigm (MEP). A hybrid methodology with geometry model and volumetric dataset to represent heterogeneous properties is proposed in this paper. Geometry model of an object can guarantee the accuracy of the final HO slices; and volumetric dataset lends the flexible manipulability and other advantages to HO representation. Two MEPs, namely distance field (DF) based and Fixed Reference Features & Active Grading Source(s) (FRF&AGS) are presented to facilitate the process of HO representation according to the designer)s input parameters. The DM can be modified interactively with users until the final satisfactory result is obtained. In this paper, a scheme of HO slicing is described. In this method, we utilize the slices contour of geometrical model as constraint to reconstruct the HO slices, which can theoretically achieve the same accuracy with the geometrical shape. Some examples of Heterogeneous object represented with our scheme are provided.

The aim of the applied systems analysis of scientific‐technological innovation is to identify the most effective innovation fields and to develop innovation strategies. This cannot be achieved without the development of theoretical foundations, practical methods and principles, a heuristic algorithm and a computer‐aided decision system. Such a system is described in this article, and represents, it is claimed, the first steps towards a computer‐aided decision system for innovation strategies.