• Journal of the Korean Society for Precision Engineering
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• v.20 no.4
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• pp.29-38
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• 2003

This paper deals with an automated computer-aided process planning and die design system with which designer can determine operation sequences even after only a little experience in process planning and die design of multi former-bolt products by multi-stage former working. The approach is based on knowledge-based rules, and a process knowledge base consisting of design rules is built. Knowledge fur the system is formulated from plasticity theories, empirical results and the empirical knowledge of field experts. Programs for the system have been written in AutoLISP for AutoCAD with a personal computer. An attempt is made to link programs incorporating a number of expert design rules with the process variables obtained by commercial FEM softwares, DEFORM and ANSYS, to form a useful package. The system is composed of four main modules. The process planning and die design module considers several factors, such as the complexities of preform geometry, punch and die profiles, specifications of available multi former, and the availability of standard parts. It can provide a flexible process based on either the reduction in the number of forming sequences by combining the possible two processes in sequence, or the reduction of deviation of the distribution and the level of the required forming loads by controlling the forming ratios. The system uses 2D geometry recognition and is integrated with the technology of process planning, die design, and CAE analysis. The standardization of die parts for multi former-bolt products requiring a cold forging process is described. The system developed makes it possible to design and manufacture multi former-bolt products more efficiently.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2006.05a
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• pp.391-394
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• 2006

In this paper, a criterion on enclosed die forging with a double action link type hydraulic die set is presented. Operational principle of the die set in enclosed die forging is introduced with emphasis on force transfer from the press and the hydraulic system to the material through links, die components and punches. Force transfer mechanism is examined and three different modes are introduced. Requirements on force equilibrium are applied to the three force transfer modes and a criterion on enclosed die forging with a double action link type hydraulic die set is drawn. The criterion is discussed to minimize forming load.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.4
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• pp.43-49
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• 2004

The production parts have required multiple processes such as drawing, piercing, blanking and notching etc. are performed with a high production rates in progressive die. In order to prevent the defects of process result, the optimization of strip process layout design, die design, die making, and tryout etc. are needed. According to these factors of die development process, it has been required that the theory and practice of metal working process and its phenomena, die structure, machining conditions for die making, die materials, heat treatment of die components, processing know-how and so on. In this study, we designed and analyzed die components through the carrying out of upper relevant matters also simulated the strip process layout of multiple stage drawing by DEFORM. Especially the result of tryout and its analysis became to the feature of this study with a system of PDDC(Progressive Die design by computer).

• Transactions of Materials Processing
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• v.21 no.3
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• pp.195-201
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• 2012

A vacuum ladling die casting system is suggested as a means to obtain a high vacuum level. A high vacuum of 17.8 mmHg is obtained by sealing the inner space of the mould. The sample product is a rear-head housing for an auto-compressor, and the die-casting with 6-cavities was conducted. The flow analysis shows that the filling speed during vacuum ladling is faster than for a non-vacuum system. The air holes in the sample product were too small to be seen with the naked eye in X-ray films. Density tests show that the high vacuum ladling system reduces the internal porosity as much as 57.8% when compared to the non-vacuum system. A defective rate of only 0.17% was found from leak testing. The results of this research prove that the high vacuum die-casting process is useful for manufacturing of aluminium components under high internal pressure.

• Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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• v.8
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• pp.273-297
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• 2003

Der Computer kann ein nutzliches, herausforderndes und kreatives Werkzeug und Hilfsmittel beim Sprachenlernen darstellen. Bei der Anwendung auf die Situation des Grammatiklernens sind die analytischen und interaktiven $F\"{a}higkeiten$ des Computers mit gutem Erfolg eingesetzt worden. Eine der attraktivsten Eigenschaften des Computers ist nun seine $F\"{a}higkeit$, mit dem Schiller zu interagieren. Gute Computerprogramme $erm\"{o}glichen$ eine ausgedehnte Interaktion zwischen Computer und $Sch\"{u}ler$. Die Computerprogramme zum Sprachenlemen befassen sich mit Grammtik. Hier habe ich ein Lemprogramm des Intelligent Tutoring Systems $f\"{u}r$ die Grammatik Perfekt programmiert. Das Intelligent Tutoring System ist ein Computerlehrer. Wenn dem $Sch\'{u}ler$ Fehler unterlaufen, gibt ein guter Lehrer nicht nur die richtige Antwort, sondern hilft dem Schiller auch, seinen Fehler zu erkennen, ihn zu analysieren und zur richtigen Antwort zu finden. Das ist eine Funktion des Intelligent Tutoring Systems. Die Programme geben die Fehlermeldung richtig oder falsch. Dem Schuler werden Aufgaben vorgelegt, die sich aus mehreren Schritten und Prozessen zusammensetzen, wobei der Computer als Werkzeug bei der Suche nach einer $L\"{o}sung$ dient In guten $Probleml\"{o}sungsprogrammen$ verfolgt der Computer den $L\"{o}sungsansatz$ des $Sch\"{u}lers$ und analysiert seine Fehler. Wenn der Schuler bei der $\"{U}bung$ die richtige Antwort $ausw\"{a}hlt$, lauft das nachste Lernprogrammn des Computers. Die $\"{U}bungstyp$ kann auf dem Computer angereichert werden, indem $pr\"{a}zise$ und hilfreiche Kommentare $f\"{u}r$ jede $Auswahlm\"{o}glichkeit$ geboten werden.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.214-218
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• 1995

Much labor, an exceedingly long lead time, and the skills of experienced engineers are required for press tool design. To reduce such problems, several CAD systems for blanking or piercing have been developed. This paper describes a computer-aided design for blanking or piercing of irregularly shaped sheet metal products. An approach to the system is based on knowledge base rules. The process planning & die design system is designed by considering several factors, such as complexity of blank geometry, punch profile, and availability of press equipment and standard parts. Therefore, after checking a production feasibility for irregular shaped sheet metal products, this system which is implemented strip layout module can carry out a process planning and generate the strip layout in graphic forms. Also this system implemented die layout module can carry out a die design for each process which is obtained form the result of an automated process planning and generate parts and assembly drawing of a die set.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.1
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• pp.72-78
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• 2008

Metal stamping is widely used in the mass-production process of the automobile. During the stamping process, air may be trapped between the draw die and the panel and/or between the punch and the panel. Air pocket rapidly not only increases forming load in the final stage, but also deforms the product just formed by compressive air inside the air pocket in knockout process. To prevent these problems air bent holes are drilled in the die to exhaust the trapped air but all processes associated with air bent holes are performed by empirical know-how of workers in the field due to lack of researches. Therefore this study developed an automated design system for predicting the shape and position, and volume of air pocket on the draw die by using the AutoLISP language under AutoCAD circumstance. The system is able to display the shape of air pocket occurred in the draw die and to calculate automatically its volume by strokes. So it makes a stepping stone to calculate theoretical size of an air bent hole and numbers according to it by predicting and analyzing the position and volume of air pocket. Results obtained from the system enable the designers or manufacturers of the stamping die to be more efficient in this field.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.6
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• pp.27-33
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• 1996

In this study, a CAD/CAM system for axisymmetric deep drawing processes has been developed. An approach to the system is based on the knowledge based system. Under the environment of CAD/CAM software of Personal Designer, the system has been written in UPL. The geometries of intermediate and final object in deep drawing process, including processes parameters are input for the CAD/CAM system. The input data can be obtained from the results of Pro_Deep. The parts drawing of die sets for each process is generated in tool design module of the CAD/CAM system. Also. the die assembly drawings can be obtained. NC commands for machining of the part can be generated in the developed CAD/CAM system.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.05a
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• pp.71-76
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• 2001

This paper describes a research work of developing system for conceptual die design system for Fine blanking. The method of approaching to the system is based on the knowledge-based rules. Knowledge for the system is formulated from experimental results and the empirical knowledge of field experts. This system has been written in VisualLISP on the AutoCAD using a personal computer and in Microsoft Visual Basic ver.6.0. Transference of data is accomplished by DXF (Drawing Exchange Format) method. This system consists of six modules, which are cognition of a drawing, cognition of shear length, calculation of shear force, materials properties database, determination of degree of difficulty of the product, determination of approximate life of punch and die modules. Results carried out in each module will provide efficiency to the designer and the manufacturer of die for Fine blanking. But the main focus of this system is the design of die for Fine blanking in the level of general concept. In order to use powerful tool in this field, developed system will be studied continuously.

• The Korean Society of Law and Medicine
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• v.10 no.2
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• pp.151-181
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• 2009

Im koreanischen Gesundheitsversicherungssystem spielt die soziale Solidarit$\ddot{a}$t Hauptrolle bei unterschiedlichen gesundheitspolitischen Entscheidungen. Daher wird manchmal vernachl$\ddot{a}$ssigt, dass auch die Qualit$\ddot{a}$tsverbesserung der Medizin und der Umfang der von der Krankenversicherung unterst$\ddot{u}$tzten medizinischen Leistungen wichtige Elemente der Krankenversciehrung sind. Um die letztere zwei Ideologien zu verwirklichen, soll insbesondere das Prinzip der Konkurrenz funktionieren k$\ddot{o}$nnen. Aber im koreanischen System hat die Konkurrenz fast gar kein Platz f$\ddot{u}$r sich. Auch das deutsche GKV (Gesetzliche Krankenversicherung)-system versucht die Sozialversicherung zu sein. Aber den deutschen Krankenversicherungssystem sieht es-speziell mit dem Vergleich vom Koreanischenzumindest viele unterschiedliche Funktionssysteme immanent zu sein. Zum einen tendiert die Einf$\ddot{u}$hrung des Gesundheitsfonds und vom Einheitlichen Beitragssatz die Sozialsolidarit$\ddot{a}$t zu verst$\ddot{a}$rken. Zum anderen tragen aber die Systeme von Zusatzbeitrag, Pr$\ddot{a}$mien und Wahltarife dazu bei, bessere Qualit$\ddot{a}$t der medizischen Leistungen zu garantieren und die Pr$\ddot{a}$ferenz von Patienten ernst zu nehmen. Es ist zwar nicht einfach vorauszusagen, zu welchen Ergebnissen diese Elementen f$\ddot{u}$hren. Aber die Funktion der unterscheidlichen Elementen, die die Konkurrenz motivieren konnen, zeigen schon viele Andeutungen f$\ddot{u}$r die Ver$\ddot{a}$nderung des korenischen Systems.