• 전자공학회논문지SC
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• 제40권4호
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• pp.251-263
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• 2003

본 논문에서는 연속시간과 이산시간에서 파라미터 불확실성을 가지는 선형 시불변 특이시스템에 대한 Η₂제어기 존재조건과 설계방법을 행렬부등식으로 제안한다. 먼저, 연속시간의 경우에는 Η₂제어기가 존재하기 위한 필요충분조건과 설계방법을 선형행렬부등식(linear matrix inequality)으로 제시하고, 이산시간의 경우에는 Η₂제어기가 존재하기 위한 충분조건과 설계방법을 행렬부등식으로 제시한다. 마지막으로 연속시간과 이산시간 각각의 경우에서, 파라미터 불확실성을 고려하여 제시한 조건들을 견실 Η₂제어문제로 확장하고, 간단한 예제를 통해 제시한 조건의 타당성을 검토해 본다.

• International Journal of Human Ecology
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• 제9권1호
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• pp.5-16
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• 2008

Development of technology in the $20^{th}$ century has made great contributions to women's lives. With the development of digital convergence, home network, and DMBs (Distance Method Bracings), the ubiquitous technology information era is expected to create a new progressive era for women. The purpose of this study is to investigate the lifestyle that Korean women would like to pursue, especially in regards to the sense of value within the personal and social life of each individual. As a method to suggest how the socio-cultural trends of women's lifestyle will change in the ubiquitous era, qualitative interviews have been conducted over 6 groups with 77 persons between the digital ages of 20s and 30s, living in Seoul. The majority had positive opinions regarding the economic, cultural, emotional, and physical prospects of the ubiquitous information environment. Results show high expectations evolved around freedom from household chores, the equality between the sexes (at home and in society), enhancing the working environment at home, an expansion of human relationships leading to creative knowledge, being able to maintain a single life without economic constraints, and the enjoyment that the internet provides. for suggestions to improve the quality of women's lifestyle through ubiquitous technology, issues such as individual based customization, time management, creating emotional hyperspaces, multi-media communication systems, and women as leaders were studied.

• Journal of Electrical Engineering and Technology
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• 제8권1호
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• pp.80-89
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• 2013

This paper presents an efficient approach for solving economic dispatch (ED) problems with nonconvex cost functions using a 'Mean-Variance Optimization (MVO)' algorithm with Kuhn-Tucker condition and swap process. The aim of the ED problem, one of the most important activities in power system operation and planning, is to determine the optimal combination of power outputs of all generating units so as to meet the required load demand at minimum operating cost while satisfying system equality and inequality constraints. This paper applies Kuhn-Tucker condition and swap process to a MVO algorithm to improve a global minimum searching capability. The proposed MVO is applied to three different nonconvex ED problems with valve-point effects, prohibited operating zones, transmission network losses, and multi-fuels with valve-point effects. Additionally, it is applied to the large-scale power system of Korea. The results are compared with those of the state-of-the-art methods as well.

• 대한기계학회논문집A
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• 제31권3호
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• pp.355-364
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• 2007

Multidisciplinary design optimization based on independent subspaces (MDOIS) is a simple and practical method that can be applied to the practical engineering MDO problems. However, the current version of MDOIS does not handle the common design variables. A new version of MDOIS is proposed and named as MDOIS/2006. It is a two-level MDO method while the original MDOIS is a single-level method. At first, system analysis is performed to solve the coupling in the analysis. If the termination criteria are not satisfied, each discipline solves its own design problem. Each discipline in the lower level solves the problem with common design variables while they are constrained by equality constraints. In the upper level, the common design variables of related disciplines are determined by using the optimum sensitivity of the objective function. To validate MDOIS/2006, mathematical problem and NASA test bed problem are solved. The results are compared with those from other MDO methods. Finally, MDOIS/2006 is applied to flow patterner design and shows that it can be successfully applied to the practical engineering MDO problem.

• 한국군사과학기술학회지
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• 제13권6호
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• pp.951-957
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• 2010

An optimal path generation method considering the safety of UGV(Unmanned Ground Vehicle) is proposed and demonstrated through examples. Among various functions of UGV, real-time obstacle avoidance is a key issue to realize realistic scenario in FCS(Future Combat Systems). A two-dimensional narrow corridor environment is considered as a test field. For each step of UGV movement, two objectives are considered: One is to minimize the distance to the target and the other to maximize the distance to the nearest point of an obstacle. A weighted objective function is used in the optimization problem. Equality and inequality constraints are taken to secure the UGV's dynamics and safety. The weighting factors are controlled by a fuzzy controller which is constructed by a fuzzy rule set and membership functions. Simulations are performed for two cases. First the weighting factors are considered as constant values to understand the characteristics of the corresponding solutions and then as variables that are adjusted by the fuzzy controller. The results are satisfactory for realistic situations considered. The proposed optimal path generation with the fuzzy control is expected to be well applicable to real environment.

• 대한기계학회논문집A
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• 제20권12호
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• pp.3871-3882
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• 1996

In this paper, a closed-form formulation for inverse kinematics of robot manipulators with kinematic redundancy under the constrained environment has been derived using the Kuhn-Tucker condition, the extended Lagrange multiplier method and the working set method. The proposed algorithm satisfies the necessaryand sufficient conditions for optimization subject to equality and inequality constraints. In addition, computationally efficient kinematic control methods have been proposed using differential kinemetics and gradient projection mehtod. The effectiveness of the proposed methods has been demonstrated with a 4-dof planar robot, and then a 7-dof spatial robot as a practical application to the nozzle dam task in the Nuclear Power Plant.

• Korean Chemical Engineering Research
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• 제52권4호
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• pp.475-480
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• 2014

플랜트 배치 최적화 문제의 목적은 장치를 연결하는 파이프의 길이를 최소화 하는데 있다. 하지만, 기존 연구들은 대체적으로 단일 층의 배치 문제를 다루고 있으며, 또한 장치 간 유지 보수에 필요한 최소 공간 확보, 사고 예방을 위한 장치 간 이격 거리등 안전 요소를 간과해 왔다. 본 연구에서는 장치 간 유지 보수에 필요한 최소 거리 확보 및 안전 이격 거리를 고려하여 플랜트 배치 문제를 MILP(Mixed Integer Linear Programming) 형태의 문제로 정의하였다. 본 문제의 목적함수는 장치 간 연결하는 파이프 비용이며 제약조건은 안전을 위한 장치 간 최소 이격 거리, 유지 보수에 필요한 공간으로 설정하였다. 하지만, 공정 특성에 따라 필요한 공간 및 작업자의 통행 등 다양한 제약조건을 수반하게 된다. 이에 따라 플랜트 배치 문제를 일반적인 수학식으로 표현하는 데 많은 제약이 있으며, 따라서 함수의 미분식을 이용하는 기존 최적화 방법론을 이용하여 문제를 해결하는 데 많은 어려움이 있다. 본 연구에서는 함수의 미분식을 적용하지 않고 이용이 가능한 경험적 최적화 기법 중 하나인 PSO(Particle Swarm Optimization)를 이용하여 최적화를 수행하였다. 본 연구에서 개발한 모델의 검증을 위해 Ethylene Oxide 공정을 2층으로 배치하는 최적화를 수행하였다.

• 한국정보과학회논문지:소프트웨어및응용
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• 제31권10호
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• pp.1304-1319
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• 2004

프로그램 시험 비용은 테스트 데이타를 생성하는 과정을 자동화함으로써 상당히 줄일 수 있다. 테스트 데이타 생성은 보통 선택된 프로그램 경로를 실행하는 입력 값들을 식별하는 데 주안점을 둔다. 지금까지 많은 연구가 있어왔지만 여전히 해결해야할 문제가 있다 그러한 문제들 중에 모양 문제가 있다. 모양 문제는 주어진 프로그램 경로를 수행하기 위해 요구되는 입력 자료구조를 밝혀내는 문제이다. 이 논문에서 이 모양 문제에 대한 새로운 방법을 제시한다. 이 방법은 주어진 경로를 포인터 역 참조가 없는 정적단일 할당문 (Static Single Assignment, SSA) 형태로 변환한다. 이는 주어진 경로 상에 존재하는 각 프로그램 문장을 등식이나 부등식과 같은 제약식으로 간주할 수 있게 해준다. 이러한 제약식에 대한 해는 각 입력 변수에 대한 'points-to relation' 형태로 나타난다. 간단한 예들을 통하여 제안한 방법에 대해 설명한다.에 대해 설명한다.

• International Journal of Internet, Broadcasting and Communication
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• 제15권4호
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• pp.366-382
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• 2023

Among the many novels penned by Thomas Hardy, the novel "Tess of the d'Urbervilles" came into print in 1891.In this novel, Hardy portrays Tess who was born and raised in a rural middle-class family but ends up working as a laborer, trapped in a society where she is subjugated by the men's wealth, leading a life marked by loneliness and isolation. The novel presents the status of women, moral struggles, and the challenging fate that they must overcome. It highlights the powerlessness of women living in a structurally unreasonable social environment, forced to depend on the ever-changing twists of destiny. This story delves into the complexities of love between the genders, moral conflicts, and the societal criticism that must be confronted. By utilizing the life of the young woman Tess, it underscores the struggle for existence and elucidates the roles, expectations, and constraints imposed on gender during the Victorian era. This research paper aims to compare the roles of women in the Victorian era in Britain and woman in contemporary Korean society. The Victorian era featured rigid gender norms, confining women to prescribed roles. In contrast, modern Korean society blends tradition and modernity, empowering women to play vital roles and reshape societal norms. Our research explores the interplay of tradition and change, providing a comprehensive understanding of women's evolving roles in both historical and contemporary contexts. We will present our discussions regarding the enduring roles that women have faced in both periods. Furthermore, we aim to highlight the distinctive roles women are called upon to play while dealing with the swift transformations in contemporary Korean society, recognizing them as essential agents in the agents in advancing Korean society.