• 한국CDE학회논문집
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• 제1권3호
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• pp.224-233
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• 1996

An automatic mesh generation scheme with triangular finite elements on three-dimensional surfaces has been developed. The surface triangulation process is performed as follows. To begin, surfaces with key nodes are transformed to two-dimensional planes and the meshes with triangular elements are constructed in these planes. Finally, the constructed meshes are transformed back to the original 3D surfaces. For the mesh generation, an irregular mesh generation scheme is employed in which local mesh densities are assigned by the user along the boundaries of the analysis domain. For this purpose a looping algorithm combined with an advancing front technique using basic operators has been developed, in which the loops are recursively subdivided into subloops with the use of the best split lines and then the basic operators generate elements. Using the split lines, the original boundaries are split recursively until each loop contains a certain number of key nodes, and then using the basic operators such as type-1 and type-2, one or two triangular elements are generated at each operation. After the triangulation process has been completed for each meshing domain, the resulting meshes are finally improved by smoothing process. Sample meshes are presented to demonstrate the versatility of the algorithm.

• Journal of Computing Science and Engineering
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• 제2권3호
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• pp.274-300
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• 2008

Software testing cost can be reduced if the process of testing is automated. However, the test data generation task is still performed mostly by hand although numerous theoretical works have been proposed to automate the process of generating test data and even commercial test data generators appeared on the market. Despite prolific research reports, few attempts have been made to evaluate and characterize those techniques. Therefore, a lot of works have been proposed to automate the process of generating test data. However, there is no overall evaluation and comparison of these techniques. Evaluation and comparison of existing techniques are useful for choosing appropriate approaches for particular applications, and also provide insights into the strengths and weaknesses of current methods. This paper conducts experiments on four representative test data generation techniques and discusses the experimental results. The results of the experiments show that the genetic algorithm (GA)-based test data generation performs the best. However, there are still some weaknesses in the GA-based method. Therefore, we modify the standard GA-based method to cope with these weaknesses. The experiments are carried out to compare the standard GA-based method and two modified versions of the GA-based method.

• 한국환경보건학회지
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• 제34권2호
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• pp.175-182
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• 2008

This study investigates the optimal conditions for electrogenerated hydrogen peroxide production and the application of the electro-Fenton process using DSA electrodes. The influences of parameters for the hydrogen peroxide generation such as electrode materials, electrolyte concentration, current, pH, air flow rate and electrode distance were investigated using a laboratory scale batch reactor. The relative performance for hydrogen peroxide generation of each of the six electrodes is : Ru-Sn-Ti > Ru-Sn-Sb > Ru > Ir > Pt > Sn-Sb. Optimum NaCl dosage, current and air flow rate were 2.0 g/l, 12.5 A and 2 l/min, respectively. When the pH is low, hydrogen peroxide concentration was high. Electrode distance dos not effect to a hydrogen peroxide generation. A complete color removal was obtained for RhB (200 mg/l) at the 8 min mark of the electro-Fenton process under optimum operation conditions of $Fe^{2+}$ 0.105 g/l and 5.0 A. The electro-Fenton process increased initial reaction and decreased final reaction time. However the effect was not high.

• 디지털콘텐츠학회 논문지
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• 제15권1호
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• pp.29-38
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• 2014

본 연구는 새로운 이야기 콘텐츠 생성의 장인 블로그 글쓰기의 스토리생성 모델을 제시하고자 한다. 이를 위해 먼저 블로그 스토리 생성의 조건을 블로그의 구조적 요인에서 찾아 RSS 기능을 통한 밀어내기의 스토리 유닛화와 트랙백을 통한 끌어오기의 스토리 확장으로 제시하였다. 다음으로 퍼스 기호학의 해석체 개념을 적용해 블로그 스토리의 제시, 변형, 순환의 과정을 설명하고 각 과정이 어떠한 의미를 창출해 내는지 살펴보았다. 이는 블로그 글쓰기의 스토리 생성 과정 자체를 하나의 통합적 기호로 제시하고 스토리텔링 관점에서 그 모델을 제시하는 선행적 연구로서 의의가 있다.

• 기록학연구
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• 제54호
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• pp.151-178
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• 2017

본 연구는 기록관리 현장의 전자기록관리영역의 문제를 확인하고 IT신기술의 도입으로 인해 급변하고 있는 기록 생산 및 관리 환경의 변화에 조응할 수 있는 새로운 전자기록관리체계의 설계를 위해 과제를 도출하는 것을 목적으로 한다. 새로운 정부의 기록관리 혁신에 맞추어 프로세스, 시스템, 인프라 모든 영역에서 이전과는 다른 차세대 기록관리 개념 설계가 이루어져야 하는 시기이다. 이러한 관점에서 차세대 기록관리의 가치와 지향이 어떠해야 하는지 방향성을 도출하고 이에 따라 프로세스, 시스템, 인프라 영역의 문제를 확인하고 과제화하였다.

• 한국생산제조학회지
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• 제5권1호
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• pp.43-50
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• 1996

From a manufacturing standpoint it would be desirable to monitor the degradation of drawing die, that is essential for the maintenance of die quality, the evaluation of product integrity and the reducing scrap. Acoustic emission is powerful method in monitoring fine wire drawing process, especially in detecting the die fracture at early stage. Experiments also suggested that acoustic emission sigals contained valuable information regarding the stage of a drawing process such as the surface appearance of products and the condition of lubrication. These informations are AE monitoring techniques a possible tool in monitoring the drawing process operation. In order to approach this, this paper discusses the nature of acoustic emission signal presented which illustrate the effects of wire and die material, lubricants, and drawing speed on the generation and the mean voltage level of acoustic emission signal. From these experimental, results, we understanded controlling factors of acoustic emission generation.

• 디지털산업정보학회논문지
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• 제8권4호
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• pp.167-175
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• 2012

Service-oriented Architecture(SOA) is one of the most recent trends in IT solutions. SOA is a paradigm for organizing and utilizing distributed capabilities that may be under the control of different ownership domains and implemented using various technology stacks. From a technical perspective SOA, can be considered a method for designing and developing IT systems where applications are constructed from loosely coupled and autonomous building blocks. And SOA is a very effective response to the problems faced by companies in terms of reusability, interoperability and reduce coupling between systems that implement their information systems. To exploit these advantages many organizations have decided to evolve their legacy systems towards this architecture. This paper proposes a modeling for SOA based business process generation and testing, and introduces its implementation in the BPEL. And we analyze business process between enterprises, modeling the service-oriented business process with BPEL to realization level. Also, we suggests that UML is used from high-level business problems to the process of low-level problem for Visual and effectively.

• 한국수소및신에너지학회논문집
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• 제22권3호
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• pp.386-401
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• 2011

Mathematical models for various steps in coal gasification reactions were developed and applied to investigate the effects of operation parameters on dynamic behavior of gasification process. Chemical reactions considered in these models were pyrolysis, volatile combustion, water shift reaction, steam-methane reformation, and char gasification. Kinetics of heterogeneous reactions between char and gaseous agents was based on Random pore model. Momentum balance and Stokes' law were used to estimate the residence time of solid particles (char) in an up-flow reactor. The effects of operation parameters on syngas composition, reaction temperature, carbon conversion were verified. Parameters considered here for this purpose were $O_2$-to-coal mass ratio, pressure of reactor, composition of coal, diameter of char particle. On the basis of these parametric studies some quantitative parameter-response relationships were established from both dynamic and steady-state point of view. Without depending on steady state approximation, the present model can describe both transient and long-time limit behavior of the gasification system and accordingly serve as a proto-type dynamic simulator of coal gasification process. Incorporation of heat transfer through heterogenous boundaries, slag formation and steam generation is under progress and additional refinement of mathematical models to reflect the actual design of commercial gasifiers will be made in the near futureK.

• 한국수소및신에너지학회논문집
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• 제21권5호
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• pp.425-434
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• 2010

Integrated gasification combined cycle (IGCC) is an efficient and environment-friendly power generation system which is capable of burning low-ranked coals and other renewable resources such as biofuels, petcokes and residues. In this study some process modeling on a conceptual entrained flow gasifier was conducted using the ASPEN Plus process simulator. This model is composed of three major steps; initial coal pyrolysis, combustion of volatile components, and gasification of char particles. One of the purposes of this study is to develop an effective and versatile simulation model applicable to numerous configurations of coal gasification systems. Our model does not depend on the hypothesis of chemical equilibrium as it can trace the exact reaction kinetics and incorporate the residence time calculation of solid particles in the reactors. Comparisons with previously reported models and experimental results also showed that the predictions by our model were pretty reasonable in estimating the products and the conditions of gasification processes. Verification of the accuracy of our model was mainly based upon how closely it predicts the syngas composition in the gasifier outlet. Lastly the effects of change oxygen are studied by sensitivity analysis using the developed model.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.723-726
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• 1998

Fault dropping is a very important part of test generation process. It is used to reduce test generation time. Test generation systems use fault simulation for the purpose of fault dropping by identifying detectable faults with generated test patterns. Two kinds of delay fault model is used in practice, path delay fault model and gate delay fault model. In this paper we propose an efficient method for gate delay test generation which shares second test vector.