• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 추계학술대회논문집 - 한국공작기계학회
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• pp.443-448
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• 2000

In this paper, multiphase optimization of machine structure is presented. The goal of first step is to obtain (i) light weight, (ii) rigidity statically. In this step, multiple optimization problem with two objective functions is treated using Pareto Genetic Algorithm. Where two objective functions are weight of the structure, and static compliance. The method is applied to a new machine structure design.

• 한국안전학회지
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• 제24권2호
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• pp.76-82
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• 2009

The NIOSH lifting equation has been used as a dominant tool in evaluating the hazard levels of lifting tasks. Although it provides two different ways for each simple and complex lifting task, the NIOSH simple lifting equation is almost used for not only simple tasks but also complex tasks. However, most of lifting tasks in industries are in the form of complex lifting. Therefore some errors occur inevitably in the evaluation of complex lifting tasks. Among complex lifting tasks, a multi-stacking task is the most popular in lifting tasks. To compensate the error in the evaluation of multi-stacking tasks by using the NIOSH simple lifting equation, a set of calculations for finding LIs(Lifting Indices) was performed for the systematically varying multi-stacking tasks. Then a regression model which finds the equivalent height in simple lifting task for multi-stacking task was established. By using this model, multi-stacking tasks can be evaluated with less error. To validate this model, some real multi-stacking tasks were evaluated as examples.

• 농촌지도와개발
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• 제21권4호
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• pp.1149-1189
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• 2014

현재 국내에서 많은 농가가 이용하는 경영진단방법 중 하나는 농촌진흥청 농업경영정보시스템 내의 농가경영컨설팅시스템에서 사용되는 경영표준진단표로, 진단결과는 DB화하여 농가경영컨설팅을 위한 자료로 활용되고 있다. 하지만 연도별 농가경영 진단결과 DB화 실적을 살펴보면 매년 실적이 조금씩 감소함을 알 수 있는데, 경영진단을 하는 농가 수의 감소는 농가가 경영진단을 통한 실질 효과가 기대에 미치지 못하였거나, 지속적으로 진단할 필요를 느끼지 못하는 등의 불만족 요인이 있음을 알 수 있다. 이러한 맥락에서 농가의 다양한 유형과 규모를 포괄하여 쓸 수 있는 컨설팅 기법의 개발과 실증사례의 발굴이 절실하다. 본 연구는 기존의 농가 중심의 농업경영체 경영진단 및 컨설팅 방법에서 부족한 요소들을 보완하고 기업형 농업경영체에도 적용이 가능하도록 경영전략 이론에서 사용되는 다중조직이론과 가치사슬모형을 적용한 경영진단 및 컨설팅기법을 소개한다. 다중조직이론 기반의 컨설팅 기법의 특징은 농업경영체의 경영전략은 크게 효율성추구와 효과성추구의 두 가지 방향이 있으며 경영체의 하부요소들이 경영 전략의 방향과 일치하는 방향으로 적합성(fit)을 맞추도록 하는 것이 특징이다. 즉, 경영체의 전략적 방향에 맞는 경영활동이 중요하며 이를 통해 한정된 자원의 분배를 최적화할 수 있게 된다. 제시된 컨설팅 기법은 농업현장의 경영체들에 실제로 컨설팅을 수행하여 현장실증한 사례를 보여줌으로써 컨설팅 기법에 대한 이해를 높일 수 있도록 하였다.

• Advances in materials Research
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• 제9권3호
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• pp.189-202
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• 2020

The objective of the present work is to investigate the effect of cutting parameters (Vc, fz and ap) on tool life and the level of vibrations velocity in the machined part during face milling operation of hardened AISI 52100 steel. Dry-face milling has been achieved in the annealed (28 HRc) and quenched (55 HRc) conditions using multi-layer coating micro-grain carbide inserts. Statistical analysis based on the Response surface methodology (RSM) and ANOVA analysis have been conducted through a plan of experiments methodology using a reduced Taguchi table (L9) in order to obtain engineering models for tool life and vibration velocity in the workpiece for both heat treatment conditions. The results show that the cutting speed has a dominant influence on tool life for both soft and hard part. Cutting speed and feed per tooth is the most significant parameters for vibration levels. Comparing the experimental values with those predicted by the developed engineering models of tool life and levels of vibrations velocity, a good correlation has been obtained (between 97% and 99%) in annealed and hard conditions.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1997년도 추계학술대회 논문집
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• pp.114-119
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• 1997

Natural vibration of the rotor system having multi-step cross-sections is analyzed. The rotary inertia and the shear deformation are considered. Torque is also included in order to simulate the power transmission system. The complex displacement and the variable separation are introduced. The exact solutions in uniform cross-section segment and the boundary conditions are used. Natural frequencies and mode shapes are obtained, especially the mode shapes are countinuous.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.401-406
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• 1991

An integrated control design and modeling method of multibody space structures is presented as a tool to control an d describe the large rotational motions of the space structures. The structures representeed with three separated substructures have independent control systems but linked with joints interacting the dynamic motions of the substructures. The effect of the structural flexibility to the control performance was analyzed and the simulation results showed that effectiveness of the designed control logic in controlling the motions of the multi-body space structures.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1998년도 추계학술대회 논문집
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• pp.54-59
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• 1998

In order to minimize straightness error of deflected shafts, a automatically bending process control system is designed, fabricated, and studied. The multi-step straightening process and the three-point bending process are developed for the geometric adaptive straightness control. Load-deflection relationship, on-line identification of variations of material properties, on-line springback prediction, and studied for the three-point bending processes. Selection of a loading point supporting condition are derved form fuzzy inference and fuzzy self-learning method in the multi-step straighternign process. Automatic straightening machine is fabricated by using the develped ideas. Validity of the proposed system si verified through experiments.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2000년도 추계학술대회 논문집
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• pp.77-85
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• 2000

The railway system is composed of large scale infrastructures and high-cost trains. For planning and analyzing this kind of complex system, simulation method can be used for efficient tool. In this research, we review basic simulation programming models and present a modeling for the elements of railway system such as rail-line infrastructure, train, time table and operational route. Additionally, some considerations on the development of multi-train traffic simulator for KyongBu-line are discussed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1994년도 추계학술대회 논문집
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• pp.336-342
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• 1994

This paper presents an useful technique for assessing the volumetric error in multi_axis machine tools using the kinematic double ball bar and 3 dimensional spherical contouring. The developed system proposes the 3 dimensional spherical contour for the error analysis. The developed system input the measured radial data, analysing the volumetric errors such as positional, strightness, angle, and squareness errors, etc. The developed system has been tested in a practical machine tool, and showed high

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2000년도 추계학술발표논문집
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• pp.101-104
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• 2000

본 연구는 우편물의 효율적인 수송을 위해 복합연계수송 개념을 도입한 Multi-commodity, Multi-modal Network Model과 이를 토대로 정식화하고 이를 적용 한 LHGO programming Model를 제안하고자 한다. 구축된 LINGO Model은 응용 Application내에 장착되어지는 Module로 구성가능하며 이를 GIS Tool인 GEOmania를 이용한 우편물 수송 DSS을 위한 Application 개발에 활용하고자 한다.