• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.527-530
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• 1997

An automated process planning system for cold forging of non-axisymmetric parts of comparatively simple shape was developed in this study. Programs for the system have been written with Visual LISP in the AutoCAD using a personal computer and are composed of four main modules such as input module, shape cognition and shape expression module, material diameter determination module and process planning module. The design rules and knowledges for th system are extracted from the plasticity theories. handbook, relevant reference and empirical knowledge of field experts. Generally, in forging, only front view is needed for expression of axisymmetric parts, but non-axisymmetric parts are needed both front view and plane. At the plane, this system cognizes the external shape of non-axisymmetric parts - number of sides of regular polygon and radius of a circle circumscribing the polygon of n sides. At the front view, the system perceives diameter of axisymmetric portions and hight of primitive geometries such as polygon, cylinder, cone, concave, convex, etc.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.7
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• pp.116-124
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• 2002

The planning of part feeder and other manufacturing automation equipments is almost always underestimated. Planning ahead for those crucial pitfalls can permit steps to take to minimize heir impacts, especially if the problems can be discovered in the planning phase, not on the shop floor. Planning process is an engineering process, namely a series of trade-offs. The effective trade-offs in the shortest amount of time can be possible with the help of a computer-aided ngineering (CAE) technique. The main parts of CAE fur part feeder are database system of fabricated workpiece parts, part feeders, part feeder components. In this study, a planning process of part feeder is presented. Especially, a systematic analysis of workpiece parts and part feeders is performed for the design of databases of CAE system.

• Transactions of Materials Processing
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• v.1 no.1
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• pp.20-32
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• 1992

This paper describes some research of Computer-Aided Process Planning and Die Design of Hot Forging for axisymmetric parts produced by the press. An approach to the system is based on knowledge based system. The system has been written in AutoLisp with personal computer. Knowledges for process planning & die design are extracted from the plasticity theories, handbooks, relevent references and empirical know-how of field experts in hot forging companies. The developed system is composed of five main modules, such as input module, process planning module, die design module, flow simulation module and output module which are used independently or in all. The final output is generated in graphic from. The developed system which aids designer provides powerful capabilities for process planning and die design of hot forging. This system also provides approximate flow pattern.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1993.04a
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• pp.393-393
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• 1993

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.46 no.4
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• pp.111-120
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• 2009

In this paper, we propose ubiWarehouse system which can efficiently manages mass and many kinds of parts such as automotive parts. First, user's work situation is defined systematically as context type of 5W1H, context-aware system is separated on function, and each module operates independently. An efficient route is selected and relevant parts frequently treated at the same time are gathered by calculating the suitability of parts and racks. If other users currently are on a visit or are supposed to visit soon, the hun of visit is changed making a concession for preventing collision. As a result, the proposed system with avoiding competition can provide users with routes for inbound or outbound parts, and can effectively use spaces of a warehouse by arranging racks to gather relevant parts to near location. Also, individual service can be offered by evaluating user propensity using history of the warehouse job, and the accuracy of stock information can be improved by processing of unexpected context and real-time renewing of warehousing and delivering.

• The Mathematical Education
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• v.38 no.2
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• pp.179-187
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• 1999

Math teachers are very short of computer tools and manipulatives to use in geometry classes of middle schools for the development of spatial abilities. At most they can ask student to make regular polyhedrons for helping the students to understand by concrete experience, but this experience is not enough to develop spatial abilities in spatial figures including the regular polyhedrons. This article is to introduce instructional materials for development of spatical ability in the regular polyhedrons using computer software, Geometer's Sketchpad. In this article, students can imagine the whole figure through the parts of a plane figure and think of the parts from the solid figure by free movement from 2 dimensions to 3 dimensions, or from 3 dimensions to 2 dimensions. Also, the instructional materials devised in this article will be good to enhance spatial abilities because the relation of 1-1 correspondence in the movement of the parts can be conserved and observed precisely, which is very hard to demonstrate and visualize by paper-and-pencil. It is recommended that this kind of materials should be developed in various ways for teachers to use them directly in their geometry classes.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.12
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• pp.5170-5188
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• 2015

This paper proposes a novel progressive secret image-hiding scheme based on the inpainting technique, the vector quantization technique (VQ) and the exploiting modification direction (EMD) technique. The proposed scheme first divides the secret image into non-overlapping blocks and categorizes the blocks into two groups: complex and smooth. The blocks in the complex group are compressed by VQ with PCA sorted codebook to obtain the VQ index table. Instead of embedding the original secret image, the proposed method progressively embeds the VQ index table into the cover images by using the EMD technique. After the receiver recovers the complex parts of the secret image by decoding the VQ index table from the shadow images, the smooth parts can be reconstructed by using the inpainting technique based on the content of the complex parts. The experimental results demonstrate that the proposed scheme not only has the advantage of progressive data hiding, which involves more shadow images joining to recover the secret image so as to produce a higher quality steganography image, but also can achieve high hiding capacity with acceptable recovered image quality.

• Journal of the Korea Society of Computer and Information
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• v.24 no.1
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• pp.67-71
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• 2019

With continued technology innovation in the fields of computer graphics (CG) and virtual reality (VR), digital animated avatars (or virtual humans) are evolving into ones that are more interactive at a suitable location such as museum, airport, and shopping mall. Specially, the form of the avatar (or the virtual human) realistically need to be expressed in a way that matches the users' physical space. In recent many researches, the form of virtual human has been expressed as mixed-reality human (MRH)-the virtual human combines with the physicality as the real part. In this paper, we propose to carry out a study comparing various MRH on co-presence and emotional response in two-typed virtual humans depending on how many actual parts are included: (1) (Level 1) small parts in the virtual human combined virtual components (e.g., the head only) and (2) (Level 2) large parts in the virtual human with the physicality as the real part such as head, arms, and upper body). We report on the implemented results of our virtual humans and experimental results on co-presence and emotional response.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.6
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• pp.1743-1752
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• 1996

In this paper, a precision inspection technique using CAD/CAI integration is proposed for the parts having very thin and sharp 3 dimensional curve features. The technique begings with feature reconstruction of turbine blades which have 3 dimensional combined feometry, such as splines, and thin circles. The alifnment procedures consistsb of two phases-rough and fine phases : rough phase alignment is based on the conventional 6 point5s probing on the clear cut surfacef, and fine phase alignment is based on the intial measurement on the 3 dimensional curved parts using an lterative measurement feed-back least sequares technique for alignment. Forf the analysis of profile tolerance of parts, the actual measured points are obtained by finding the closet points on the CAD geometry by the developed subdivision technique and the Tschebycheff norm is applied based on iterative fashion, giving accurate profile tolerance value. The developed inspection technique is applied to practical procedures of blade manufacturing and demonstrated high performance.

• Journal of Korean Institute of Industrial Engineers
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• v.25 no.1
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• pp.35-46
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• 1999

The introduction of general purpose machining centers and the information system based on computer network has added a new control problem to the classical job shop control problems: a routing problem. A routing problem is to determine the machine on which a part will be processed. The modern manufacturing systems are given much system status information including the arrival time of the future parts via the computer network for automation. This paper presents and tests the performance of a routing procedure, LARP(Look-Ahead Routing Procedure) which uses look-ahead information on the future arrival of parts in the system. The manufacturing system considered in this paper has multi-stations which consists of general purpose machines and processes parts of different types. The application of LARP under many operating conditions shows that the reduction of part flow time and tardiness from the cases without using this information is up to 8% for flow time and 21% for tardiness. The procedure introduced here can be used for many highly automated systems such as an FMS and a semi-conductor fabrication system for routing where the arrivals of parts in the near future are known.