• Communications of the Korean Mathematical Society
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• v.35 no.2
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• pp.469-480
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• 2020

Let R be a commutative ring with identity and M a unital R-module. We give a new generalization of exact sequences called e-exact sequences. A sequence $0{\rightarrow}A{\longrightarrow[20]^f}B{\longrightarrow[20]^g}C{\rightarrow}0$ is said to be e-exact if f is monic, Imf ≤_e Kerg and Img ≤_e C. We modify many famous theorems including exact sequences to one includes e-exact sequences like 3 × 3 lemma, four and five lemmas. Next, we prove that for torsion-free module M, the contravariant functor Hom(-, M) is left e-exact and the covariant functor M ⊗ - is right e-exact. Finally, we define e-projective module and characterize it. We show that the direct sum of R-modules is e-projective module if and only if each summand is e-projective.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.190-195
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• 2008

This study aims to develop the thermal performance and economic analysis program of solar heating system applied to district heating systems. The program, named SOLAN-DHS, is consisted of four modules like as user's interface for system input/output, library, and utilities and a calculating engine. SOLAN-DHS simplifies user's input data through the database and can design 5 different types of solar systems. Due to the user-friendly layout, all design parameters can be changed quickly and easily for the influence on system efficiency. The reliability of SOLAN-DHS was finally verified by the experiments.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.1024-1030
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• 1993

In manufacturing press die with free surface, grinding operation is an important post process for surface finish and dimensional accuracy. With the advancement of NC technology. surface grinding operation is increasingly replaced by the gantry type manipulator. As the mechanics for grinding operation is different from machining operation, conventional CAM system for machining operation is hard to apply. In this. paper, we develop a five-axis CAM system by which an efficient gantry trajectory can be planned and verified. The developed system consists of four conceptual modules; namely CAD, PROCESS. CAM, and ANALYSIS. In the CAD module, the machined surface is represented by CL-data or surface modeler, and process parameters are specified by the PROCESS module. Then, the CAM module generates a series of grinding paths based on the grinding mechanics together with process databases for tool spaces and grinding conditions. The generated paths are verified via ANALYSIS module. Validation via real experiments is left for further study.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.1 no.1
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• pp.104-112
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• 2001

Simply, Nonlinear dynamics theory means the complicated and noise-like phenomena originated form nonlinearity involved in deterministic dynamical system. An almost all the natural signals have nonlinear property. However, there exist few analysis software tool or package for a research and development of applications. We develop nonlinear time series analysis simulator is to provide a common and useful tool for this purpose and to promote research and development of nonlinear dynamics theory. This simulator is consists of the following four modules such as generation module, preprocessing module, analysis module and ICA module. In this paper, we applied to Electroencephalograph (EEG), as it turned out, our simulator is able to analyze nonlinear time series. Besides, we could get the useful results using the various parameters. These results are used to diagnostic the brain diseases.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.92.6-92
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• 2001

MSC is being developed to be installed on KOMPSAT(Korea Multi-Purpose Satellite-II and to provide high resolution multi-spectral. MSC consists of three main subsystems. One is EOS(Electro-Optics Subsystem), another is PMU(Payload Management Unit) and the other is PDTS(Payload Data Transmission Subsystem). There is an SBC(Single Board Computer) in the PMU to control all MSC subsystems. SBC incorporates Intel 80486 as a main processor and VxWorks as a real-time operating system. SBC software consists of four main tasks and several modules to deal with all control information for imaging and all the state of health telemetrv data, and to perform interface with another MSC units. SBC software also has to handle a lot of commands in order for MSC to perform his mission. One mission command consists of a series of related commands, which are In be executed in the designated sequence, with a specified time ...

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.117.2-117
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• 2002

In this paper, a software framework is proposed for the personal robot located on home network. The proposed software framework is divided into four layers-a transparency layer, a behavior layer, a distributed task layer, and a mission scenario layer. The transparency layer consists of a virtual machine for platform transparency, and a communication broker for communication transparency among behavior modules. The communication architecture includes both server/client communication and publisher/subscriber communication. A mission scenario is assumed to be a composition of sequentially planned distributed tasks. In addition to the software framework, a new concept, personal robot design cent...

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.535-539
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• 2001

The aim of this paper presents to develop a computer-aided design system for water gate on AutoCAD R2000system. The developed system has been written in AutoCAD and Visua ILISP with a personal computer, and is composed four modules which are the gate-lifter input module, guide-frame input module, template input module and upgrade module. Based on knowledge-based rules, the system is designed by considering several factors, such as width and height of a water gate, material, object of product and maximum depth of water. Employing the developed system enable the designer and manufactures of water gate to be more efficient in this field, and its potential capability for enhancement included FEM(Finite Element Method) and quotation system.

• Journal of the Korean Society for Precision Engineering
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• v.8 no.4
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• pp.55-63
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• 1991

This paper deals with development of a Computer Aided Process Planning System based on knowledge base in addition to database for injection mold as a part of Computer Integrated Manufacturing System for injection mold manufacture. The prposed system consists of four modules such as manufacturing feature code generation module machine tool selection and sequencing module, operation and cutting tool selection mudule and standard time estimation module. The system is programmed by using Turbo Pascal on the IBM-PC/AT. The performance of the system is evaluated by using real problems and the test results indicate that the proposed system is a practical and efficient system.

• 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.

• Computers and Concrete
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• v.14 no.3
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• pp.263-277
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• 2014

This study investigated four electric field configurations of two-dimensional accelerate lithium migration technique (ALMT), including line-to-line, plane-to-line, contour-to-line and plane-to-plane, and analyzed the ion migration behavior and efficiency. It was found that the free ion distribution diagram and voltage distribution diagram were similar, and ions migrated in the power line direction. The electrode modules were used for the mortar specimen with w/c ratio of 0.5. The effectively processed areas accounted for 14.1%, 39.0%, 49.4% and 51.4% of total area respectively on Day 28. Larger electrode area was more advantageous to ion migration. In addition, it was proved that the two-dimensional electric field could be divided into different equifield line active regions, and regarded as affected by one-dimensional electric field, and the ion migration results in various equifield line active regions were predicted by using the duration analysis method based on the theoretical model of ion migration obtained from one-dimensional test.