• 정보처리학회논문지D
• /
• 제10D권5호
• /
• pp.845-858
• /
• 2003

1980년대 이후, 소프트웨어 위기에 대응하기 위한 다양한 소프트웨어 공학적 기법들이 출현하기 시작 하였고, 현재 소프트웨어의 질적 항상 및 생산성 향상을 꾀하기 위한 개발 지침으로 소프트웨어 개발 프로세스를 적용하는데 관심이 집중되어지고 있다. 그러나 대부분의 방법론들이 앞으로 구축한 새로운 시스템의 재사용성 확보에 치중할 뿐, 기존의 레거시 시스템 자원을 재사용하여 새로운 시스템을 구축하는 재공학 방법은 지원하지 못하고 있는 실정이다. 본 논문에서는 레거시 시스템의 효율적 진화를 위한 재공학 프로세스(Reengineering Process)로 RUP를 확장, 커스터마이징하여 구성한 RUP+re을 제시한다. RUP+re는 Small-h 모델을 바탕으로 크게 역공학 워크플로우(Reverse Engineering Workflow), 변환 워크플로우(Transformation Workflow), 진화 워크플로우(Evolution Workflow)로 구성되어진다. RUP+re의 각 워크플로우와 세부스텝을 제공하고 재공학 사례 연구론 통하여 실질적으로 프로세스를 검증함으로서 레거시 시스템 자원의 진화론 위한 소프트웨어 재공학 프로세스 구축에 효율적인 지침을 제공한다.

• 한국정밀공학회지
• /
• 제28권2호
• /
• pp.219-225
• /
• 2011

Silicone resin is recently used as encapsulant for high-power LED module due to its excellent thermal and optical properties. In the present investigation, finite element analysis of cure process was attempted to examine residual stress evolution behavior during silicone resin cure process which is composed of chemical curing and post-cooling. To model chemical curing of silicone, a cure kinetics equation was evaluated based on the measurement by differential scanning calorimeter. The evolutions of elastic modulus and chemical shrinkage during cure process were assumed as a function of the degree of cure to examine their effect on residual stress evolution. Finite element predictions showed how residual stress in cured silicone resin can be affected by elastic modulus and chemical shrinkage behavior. Finite element analysis is supposed to be utilized to select appropriate silicone resin or to design optimum cure process which brings about a minimum residual stress in encapsulant silicone resin.

• 한국시뮬레이션학회논문지
• /
• 제14권3호
• /
• pp.43-54
• /
• 2005

For the effective design of automated distribution center composed of Automated Storage/Retrieval System, Automated Guided Vehicle System, and Conveyor System, we proposed an analysis method to determining. design and control parameters with multiple performance objectives using Compromise Programming, which can resolve the dilemma of conflicting objectives. The Evolution Strategy generates the optimal solutions for each objectives. The Analytic Hierarchy Process selects the best solution among the alternatives generated from Evolution Strategy. The Regression Analysis formulates the objective functions for each objectives. By reducing deviations between goal values and target values generated from Analytic Hierarchy Process, Compromise Programming determines design and control parameters by compromising the multiple objectives formulated using Regression Analysis. When the parameters of system are changed, this proposed analysis method has a benefit of reducing costs and time without repeating whole simulation run.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2005년도 춘계학술대회 논문집
• /
• pp.291-294
• /
• 2005

The microstructure evolution of Alloy 718 during the direct age(DA) process was predicted using the recrystallization model and finite element analysis. The DA process of Alloy 718 was performed in two-step forging using capsulated cylindrical billets of 122mm in diameter and 180mm in height. In order to evaluate the microstructural change during the forging, a dynamic recrystallization model of Alloy 718 was implemented onto the user-subroutine of the commercial FEM code. The prediction of microstructure evolution in DA processed Alloy 718 pancake was compared with experimental results.

• 전자공학회논문지CI
• /
• 제40권3호
• /
• pp.144-154
• /
• 2003

이 논문에서는, 이진 논리 함수(binary logic function)로 표현되는 개념들에 대한 새로운 학습방법인 논리적 진화방식(Logical Evolution)을 제안하였다. 그리고 이 방법을 통해 기존 귀납학습의 문제점들을 해결하고자 시도하였다. 사용하는 특징이 사전지식의 영향을 적게 받도록, 학습과정에서 얻어진 정보를 이용하여 특징을 생성하고 동시에 이를 이용하여 학습한다. 그리고 전체 자료가 아니라 개별 자료를 이용하여 특징생성 및 학습을 수행한다. 그 결과 새로운 문제가 주어지거나 입출력이 변경되는 경우에도, 이전의 특징을 재사용할 수 있으며 겨우에 따라서는 보다 효율적인 학습이 가능하다. 논리적 진화방식은 5가지 연산으로 구성되며, 이러한 연산들은 특징생성 및 학습 과정에서 논리적 평가방식(logical evaluation)에 의해 적절하게 선택되고 실행된다. 제안된 방법의 성능을 평가하기 위해서 MONK 문제와 새로 정의한 다른 문제를 이용하였다.

• 한국게임학회 논문지
• /
• 제9권1호
• /
• pp.21-31
• /
• 2009

본 연구는 게임을 구성하는 핵심적인 구성 요소인 규칙을 특성에 따라 단계별로 분류하고 각 규칙 단계의 성립 근거와 개념을 정의한다. 이러한 정의를 바탕으로 게임 규칙의 변화 과정을 분석하고 게임 규칙이 진화를 통해서 발전해 나간다는 점을 확인한다. 디지털 게임 규칙의 변화 구조는 환경에 따라 이루어지는 생물의 진화 경로와 같은 구조를 가진다. 이러한 새로운 관점에서 바라보는 이 연구를 통해서 게임 규칙의 진화와 생물의 진화 경로의 구조적 유사성을 살펴본다. 또한 디지털 게임 규칙이 진화하는 과정을 새로운 시각을 통해서 분석하고 개념화하고자 한다. 나아가 이 연구를 바탕으로 게임을 새로운 학문적 대상으로서 재발견하고자 한다.

• Geomechanics and Engineering
• /
• 제20권1호
• /
• pp.29-41
• /
• 2020

It is extremely important to obtain rock strength parameters for geological engineering. In this paper, the evolution of sandstone cohesion and internal friction angle with plastic shear strain was obtained by simulating the cyclic loading and unloading tests under different confining pressures using Particle Flow Code software. By which and combined with the micro-crack propagation process, the mesoscopic mechanism of parameter evolution was studied. The results show that with the increase of plastic shear strain, the sandstone cohesion decreases first and then tends to be stable, while the internal friction angle increases first, then decreases, and finally maintains unchanged. The evolution of sandstone shear strength parameters is closely related to the whole process of crack formation, propagation and coalescence. When the internal micro-cracks are less and distributed randomly and dispersedly, and the rock shear strength parameters (cohesion, internal friction angle) are considered to have not been fully mobilized. As the directional development of the internal micro-fractures as well as the gradual formation of macroscopic shear plane, the rock cohesion reduces continuously and the internal friction angle is in the rise stage. As the formation of the macroscopic shear plane, both the rock cohesion and internal friction angle continuously decrease to a certain residual level.

• Geomechanics and Engineering
• /
• 제36권2호
• /
• pp.121-130
• /
• 2024

Many foundation projects are built on red-bed soft rocks, and the damage evolution of this kind of rocks affects the safety of these projects. At present, there is insufficient research on the damage evolution of red-bed soft rocks, especially the progressive process from mesoscopic texture change to macroscopic elastoplastic deformation. Therefore, based on the dual-porosity characteristics of pores and fissures in soft rock, we adopted a cellular automata model to simulate the propagation of these voids in soft rocks under an external load. Further, we established a macro-mesoscopic damage model of red-bed soft rocks, and its reliability was verified by tests. The results indicate that the relationship between the number and voids size conformed to a quartic polynomial, whereas the relationship between the damage variable and damage porosity conformed to a logistic curve. The damage porosity was affected by dual-porosity parameters such as the fractal dimension of pores and fissures. We verified the reliability of the model by comparing the test results with an established damage model. Our research results described the progressive process from mesoscopic texture change to macroscopic elastoplastic deformation and provided a theoretical basis for the damage evolution of these rocks.

• 소성∙가공
• /
• 제32권5호
• /
• pp.268-275
• /
• 2023

ISO 21029 cryogenic vessel is used to transport cryogenic fluids. High-manganese steel (High-Mn steel) is widely regarded as suitable for use at cryogenic temperatures. The conventional way of manufacturing an ellipsoidal vessel head involves incremental stretching, followed by a spinning process. In this study, an alternative method for forming an ellipsoidal vessel head was proposed. Finite element analysis (FEA) was used to theoretically examine the strain evolution during a multi-stage forming process, which involved progressive stretching, deep drawing, and spinning of High-Mn steel. The distribution of effective strain and strain components were analyzed at different regions of the formed part. The FEA results revealed that only normal strains were evident in the dished region of the vessel head due to the stretching process. However, the flange region experienced complex strain evolution during the subsequent deep drawing and spinning process.

• Geomechanics and Engineering
• /
• 제23권2호
• /
• pp.127-137
• /
• 2020

To study the reverse fault formation process and the stress evolution feature, a simulation test system of reverse fault formation is developed based on the analysis of reverse fault formation mechanism. The system mainly consists of simulation laboratory module, operation console and horizontal loading control system, and data monitoring system. It can represent the fault formation process, induce fault crack initiation and simulate faults of different throws. Simulation tests on reverse fault formation process are conducted by using the simulation test system: horizontal loading is added to one side of the model. the bottom rock layer cracks under the effect of the induction device. The crack dip angle is about 29°. A reverse fault is formed with the expansion of the crack dip angle towards the upper right along the fracture surface and the slippage of the hanging wall over the foot wall. Its formation process unfolds five stages: compressive deformation of rock, local crack initiation, reverse fault penetration, slippage of the hanging wall over the foot wall and compaction of fault plane. There is residual structural stress inside rock after fault formation. The study methods and results have guiding and referential significance for further study on reverse fault formation mechanism and rock stress evolution.