• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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• pp.813-818
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• 1989

A two compartmented autoclave reactor for the polymerization of low density polyethylene is analyzed with respect to the effects of heat transfer and operation variables. Each compartment being considered as a completely mixed cell, two CSTRs model is proposed. The system shows various multiplicity features of steady state and periodic oscillatory motions. Heat removal efficiency and initiator supplement appear to have significant effect on the conversion of monomer with the temperature properly maintained, which should be taken into account in the reactor design.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.146-151
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• 1992

A two-compartment four-cell model is developed for the adiabatic autoclave slim type reactor for free radical polymerization of low density polyethylene(LDPE). The mass and energy balances give rise to a set of ordinary differential equations, and by analyzing the system it is possible to predict properly not only the reactor performance but also the properties of polymer product. The steady state multiplicity is found to exist and examined by constructing the bifurcation diagram. The effects of various operation parameters on the reactor performance and polymer properties are investigated systematically to show that the temperature distribution plays the central role for the properties of polymer product. Therefore, it is essential to establish a good control strategy for the temperature in each compartment. In this study it is shown that the reactor system can be adoptively controlled by pole-placement algorithm with conventional PID controller. To accomplish a satisfactory control, the estimator and controller are initialized during the period of start-up.

• 한국디지털건축인테리어학회논문집
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• 제7권1호
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• pp.35-42
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• 2007

Common residential environment is synthetic forms promote with organic organization of varied cultures and images. Users perceive and classify about these environments of feeling and atmosphere of each elements through their experiences and memories, not fixed point of view. In Korea, park designing of common residential room is in operation monotonously attach importance to economical efficiency without aesthetic structures, varied tries of materials, multiplicity, congruity of surrounding, and user-oriented plan. Recently, in policy of park designing has elements that obstruct to characteristic of environment because of applied to wrong guidelines which are end in investigation to model of an advanced countries'. In conclusion, this investigation shows improve on quality of park planning with the pivot of the matter is for users of common residential room. and park planning needs to multidimensional achieve.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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• pp.461-467
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• 1998

In spite of significant nonlinearities even in the simplest model, some types of steady-state and dynamic behavior common for nonlinear systems have never been associated with distillation columns. In recent years, multiplicity of steady states has been a subject of much research and is now widely accepted. Subsequently, stability of steady states has been explored. Another phenomenon that. although widely observed in chemical reactors, has not been associated with models of distillation columns is the existence of periodic oscillations. In this article we study the steady-state and dynamic behavior of the azeotropic distillation of the ternary homogeneous system methanol-methyl butyrate-toluene. Our simulations reveal nonlinear behavior not reported in earlier studies. Under certain conditions, the open-loop distillation system shows a sustained oscillation associated with branching to periodic solutions. The limit cycles are accompanied by traveling waves inside the column. Significant underdamped oscillations are also observed over a wide range of product rates.

• 품질경영학회지
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• 제27권1호
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• pp.195-210
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• 1999

The multiplicity of software packages brings about a choice problem to the end-user and a multi-fold intensity to the competing developer. This study intends to provide guidelines solving the problems for both the end-user and the developer of packages for automatic statistical analyses. For the purpose, we adopt an appropriate evaluation model in terms of user-perceived quality through the applicable criteria and an evaluation method. The result of empirical study is described, which shows that the weight of each criterion is dynamic along usage levels. Briefly, functionality, usability, and reliability are key factors to contribute to the perceived quality. The empirical study also illustrates a comparative analysis on the dominant products, SAS and SPSS, in Korea.

• 한국IT서비스학회:학술대회논문집
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• 한국IT서비스학회 2006년도 추계학술대회
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• pp.60-65
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• 2006

The authors map some of the current Business Models in the Massively Multiplayer Online Player scenario. These maps represent Value Creation Systems by resorting to Value Net constructs and notations, and are offered here as a proof of concept and utility. The authors claim that these mappings can enable readers, managers and IT experts, to build new insights onto such Business Models and develop requirements for Information System infrastructure. When approaching the Value Creation System as a Value Net the goal is to think outside the conceptual box of Value Chains and understand how the different activities interact, by exposing the multiplicity of value types and flows. In doing this study the authors are attempting to synthesize a new Business Model proposal that could underlie the development of an infrastructure for the collaborative creation, distribution and exploration of online massively multiplayer games, beyond the traditional producer-consumer roles.

• 한국정보시스템학회지:정보시스템연구
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• 제12권1호
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• pp.145-158
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• 2003

Workflow is the automation of a business process, in whole or part, during which documents, information or tasks are passed from one participant to another for action, according to a set of procedural rules. The software selection problem is made difficult by the multiplicity of competing products and the lack of expertise and experience of users in the methods of software evaluation. Although the selection process for workflow is similar to that proposed for the acquisition of any software packages, differences arise in their evaluation criteria and choice methods. In this paper, we suggest the Analytic Hierarchy Process(AHP) method for selecting workflow software. The AHP is an intuitively easy method for formulating and analyzing decisions. It was developed to solve a specific class of problems that involves prioritization of potential alternate solutions. We showed how to evaluate 9 commercial workflow products by deciding the relative importance of the main criteria in the AHP model. We utilized the evaluation data for criteria ready suggested by specialist groups. Our methodology will be helpful to those who are going to adopt a best workflow product in their organizations. Although the criteria and their evaluation scores regarding workflow products are suggested, it is not easy to apply them to a real case and get solutions without a model.

• 정보화연구
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• 제9권2호
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• pp.167-176
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• 2012

한국군은 LISI 모델을 활용하여 소요제기 및 획득단계에서 체계의 상호운용성 수준측정 및 평가를 실시하고 있다. 그러나 LISI 모델은 체계 간 상호운용성 평가에 초점이 맞추어져 있기 때문에 다수 체계가 유기적으로 연결된 복합체계의 상호운용성 평가에는 제한적이다. 또한 LISI 모델은 정량적이기 보다는 정성적인 접근방법이기 때문에 상호운용성 의사결정에 가시적인 정보 제공에는 한계가 있다. 이에 대한 해결책으로 본 연구에서는 복합체계의 정량적인 상호운용성 평가 방법론을 제안한다. 제안 방법론에서는 아키텍처를 활용하여 임무 프로세스를 지원하는 복합체계가 식별되고, 체계의 다중도와 유사도 계수를 기반으로 상호운용성 평가가 이루어진다. 그리고 제안 방법론의 효용성을 보이기 위해 사례연구 결과를 제시한다.

• 대한인간공학회지
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• 제17권1호
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• pp.115-123
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• 1998

We study the ski wear which are compared at the materials and the designes and their human physiological and phychological response during exercise in a cold and air-conditioned enviroments. Five men exercises in the experiment room with four types of ski-wears : two of one-piece and two of two-piece : two of special material and two of a normal material, respectively. We keep the environment at $-5^{\circ}C$ and speed of 3.6 mile/hr during the measurement of 13 points, which is a mean model of the Muju ski-resort at January 1996. We conclude the followings : 1. The ski-wear with special materials have higher than the normal type at mean skin temperature and rectal temperature. 2. Changes of temperature withing the clothes during the exercise is small, but the humidity within the clothes abruptly increases because of the weight loss. 3. Type A ski-wear with the special material has $295.5g/m^2hr$ weight loss, which is higher, and type D ski-wear is smaller 4. The special material shows comfortable in the thermal sensation. 5. In the design aspect of the ski-wears, the two-piece type ski-wear shows higher skin temperature and temperature & humidity within the clothes than the one-piece type due to the effect of the multiplicity.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2001년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2001
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• pp.117-124
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• 2001

A simplified method fur the eigenpair sensitivities of damped system with multiple eigenvalues is presented. This approach employs a reduced equation to determine the sensitivities of eigenpairs of the damped vibratory systems with multiple natural frequencies. In the proposed method, adjacent eigenvectors and orthonormal conditions are used to compute an algebraic equation whose order is (n+m)x(n+m), where n is the number of coordinates and m the number of multiplicity of multiple natural frequencies. The proposed method is an improved Lee and Jung's method which was developed previously. Two equations are used to find eigenvalue derivatives and eigenvector derivatives in Lee and Jung's method. A significant advantage of this approach over Lee and Jung's method is that one algebraic equation newly developed is enough to compute such eigenvalue derivatives and eigenvector derivatives. This method can be consistently applied to both structural systems with structural design parameters and mechanical systems with lumped design parameters. To demonstrate the theory of the proposed method and its possibilities in the case of multiple eigenvalues, the finite element model of the cantilever beam and 5-DOF mechanical system in the case of a non-proportionally damped system are considered as numerical examples. The design parameter of the cantilever beam is its height. and that of the 5-DOF mechanical system is a spring.