• The Transactions of the Korean Institute of Electrical Engineers
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• v.34 no.8
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• pp.301-307
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• 1985

The first four generations of computers are all based on a single basic design: the Von Neuman Processor, which is sequential and does one operation at a time. Efforts to develop concurrent or parallel computers have been carried on for many years. Data flow approach is significant in these efforts to make high speed parallel machines and expected a great deal of parallelism. In this paper we propose a preliminary data Flow Machine Model operating asynchronously on the base of Node Labelling. We introduce a concept of Node Labeling for this purpose which is relevant to the Data dependency and Parallelism. And we explain how the Node Tokens are fired in the proposed system.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.3
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• pp.115-121
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• 2001

In micro automation technology, the concurrent realization of a high resolution and a large operating rage has been achieved by a dual actuator, usually called by piggy-back system, conventionally. But, because of its manufacturing cost, the complexity of control, and the limit of overall bandwidth, the contract-free and single servo actuators have been suggested with specific applications. In this paper, we suggest a novel non-contact surface actuator suing combination of the Lorentz force and the magnetized force, and discuss the actuating principles including an analytical approach. Differently from the existing planar system, an operating range of the suggested system can be expanded by an additional attachment of active elements. Therefore, it is estimated to be suitable for the next-generation moving system.

• Korean Journal of Computational Design and Engineering
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• v.10 no.2
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• pp.77-88
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• 2005

This paper introduces a project for the development of an F-125 machine using 3D PLM systems including 3D CAD, CAM, CAE, PDM, and DMU systems. Here, the F-125 machine is a formula racing car equipped with a 125cc motorcycle engine. A development process and computer-integrated environment was established using 3D PLM systems on the conceptual basis of concurrent and virtual engineering. A DMU model for a full vehicle was built using CATIA V.5 and used to check interference between parts and to simulate assembly process. This DMU-based approach enables to find and fix manufacturing problems in the early design stage. All development activities have been done by the graduate and undergraduate students of the automotive engineering department of Kookmin University. Through the project, the students could acquire knowledge about car development process and 3D PLM systems in automotive industry.

• Proceedings of the Korean Information Science Society Conference
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• 2001.04b
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• pp.16-18
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• 2001

Despite extensive research on R-trees, most of the proposed schemes have not been integrated into existing DBMS due to the lack of protocol to provide consistency in concurrent environment. R-link tree is an acceptable data structure to deal with this issue., but still not enough. In this paper, we focus on a simplified predicate locking mechanism based on R-link tree for concurrency control and phantom protection. An in-memory operation control list (OCList) used to suspend some conflicting operations is designed here. The main features of this approach are (1) it can be implemented easily and do not need any extra information. (2) Only-one-lock is held when descending R-tree even when node split happens, while lock-coupling scheme is performed when ascending. No deadlocks are possible. (3) Searches and insertions are not unnecessarily restricted. (4) Insert and Delete phantom in R-link tree are avoid through beforehand predication.

• Transactions of Materials Processing
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• v.13 no.2
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• pp.174-179
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• 2004

The effect of grain refinement on the plastic deformation behaviour of nanocrystalline metallic materials is investigated. A phase mixture model in which a single phase material is considered as an effectively two-phase one is discussed. A distinctive feature of the model is that grain boundaries are treated as a separate phase deforming by a diffusion mechanism. For the grain interior phase two concurrent mechanisms are considered: dislocation glide and mass transfer by diffusion. The proposed constitutive model was implemented into a finite element code (DEFORM) using a semicoupled approach. The finite element method was applied to simulating room temperature tensile deformation of Cu down to the nanoscale grain size in order to investigate the pre- and post-necking behaviour.

• Asia pacific journal of information systems
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• v.5 no.1
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• pp.219-235
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• 1995

Complexity of some problems often transcends the problem solving capability of human individuals. As such, we cannot but take a collaborative approach to those complex problems. Collaboration while using computing systems can take place through shared objects. However, current commercial DBMSs do not provide a satisfactory control for concurrent access to objects shared by collaborators. A new concurrency control scheme is proposed which will help a group of people work in a more collaborative and natural way. The idea of softlock is refined into three different kinds of softlocks and the roles of collaborators are taken into account in the proposal of the new scheme. Although these softlocks are illustrated together with read/write hardlocks in this paper, the use of softlocks can be extended to be exploited with other kinds of hardlocks, for example, of granularity locking.

• Korean Journal of Computational Design and Engineering
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• v.12 no.6
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• pp.452-460
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• 2007

To achieve rapid developments and cost savings in manufacturing industries including automotive die shops, new paradigm and its supporting systems of information managements through total product life cycle are needed for concurrent and collaborative engineering. For manufacturing of automotive press dies, integrated and efficient managements of PPR information including product, manufacturing process and resource are essential. In this paper, we introduce a PLM approach to achieve engineering collaborations in product development and production of automotive dies. To prove concepts and benefits of PPR information managements, we implement new business workflow and detail procedures, PPR information management system and other related applications. By PPR information managements in PLM, improvements in quality of engineering results and savings in time from design to production of dies are possible.

• Journal of Microbiology and Biotechnology
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• v.16 no.9
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• pp.1355-1361
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• 2006

The simultaneous saccharification and fermentation (SSF) process consists of concurrent enzymatic saccharification and fermentation. In the present cybernetic model, the saccharification process, which is based on the modified Michaelis-Menten kinetics and enzyme inhibition kinetics, was combined with the fermentation process, which is based on the Monod equation. The cybernetic modeling approach postulates that cells adapt to utilize the limited resources available to them in an optimal way. The cybernetic modeling was suitable for describing sequential growth on multiple substrates by Brettanomyces custersii, which is a glucose- and cellobiose-fermenting yeast. The proposed model was able to elucidate the SSF process in a systematic manner, and the performance was verified by previously published data.

• Proceedings of the IEEK Conference
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• summer
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• pp.87-91
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• 2004

This research presents distributed database and knowledge-base modeling approach for intelligent product design system. The product design information in this study is described by a collection of rules and design knowledge that are utilized according to the product development procedures. In this work, a network-based architecture has been developed to enable dispersed designers to simultaneously accomplish remote design tasks. A client/server communication diagram has also been proposed to facilitate consistent primary information modeling for multi-user access and reuse of designed results. An intelligent product design system has been studied with the concepts of distributed database and network-based architecture in order to support concurrent engineering design and automatic design part assembly. The system provides the capability of composing new designs from proper design elements stored in the database and knowledge-base. The distributed intelligent product design is applied to the design of an automobile part as an example.

• Journal of Electrical Engineering and information Science
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• v.2 no.6
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• pp.28-35
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• 1997

A new approach concurrent transistor sizing and buffer insertion for low power optimization is proposed in this paper. The method considers the tradeoff between upsizing transistors and inserting buffers and chooses the solution with the lowest possible power and area cost. It operates by analyzing the feasible region of the cost-delay curves of the unbuffered and buffered circuits. As such the feasible region of circuits optimized by our method is extended to encompass the envelop of cost-delay curves which represent the union of the feasible regions of all buffered ad unbuffered versions of the circuit. The method is efficient and tunable in that optimality can be traded for compute time and as a result it can in theory near optimal results.