• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2005년도 춘계학술대회 논문집
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• pp.144-149
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• 2005

In recent years, as the robot technology is developed the researches on the artificial muscle actuator that enable robot to move dextrously like biological organ become active. The widely used materials for artificial muscle are the shape memory alloy and the electroactive polymer. These actuators have the higher energy density than the electromechanical actuator such as motor. However, there are some drawbacks for actuator. SMA has the hysterical dynamic characteristics. In this paper the segmented binary control for reducing the hysteresis of SMA is proposed and the simulation of anthropomorphic robotic hand is performed using ADAMS.

• 한국신뢰성학회지:신뢰성응용연구
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• 제16권1호
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• pp.64-70
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• 2016

Purpose: The purpose of this study was to evaluate performance reliability of stroke patients using kinematic analysis. Methods: A protocol to evaluate performance reliability was performed for three tasks on 20 stroke patients and 10 normal people. The tasks include hand to head (HH) task, hand to mouth (HM) task, and hand to target (HT) task. Results: The affected arms showed smaller joint angle, slower peak velocity, longer time to peak velocity for task performances than control group. Also, slower peak velocity and longer movement time for task performance in unaffected arm of stroke patients were obtained compared with the control group. Conclusion: Kinematic analysis is very useful quantitative tool to provide understanding on upper extremity function of stroke patients.

• 한국기계가공학회지
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• 제11권1호
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• pp.13-19
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• 2012

In this study, ultrasonic vibration tool designed and made by using FEM analysis. And machining test was carried out in various machining conditions using ultrasonic vibration capable CNC machine. For work material, alumina ceramic ($Al_2O_3$) was used while for tool material diamond electroplated grinding wheel was used. To evaluate ultrasonic vibration effect, grinding test was performed with and without ultrasonic vibration in same machining condition. In ultrasonic mode, ultrasonic vibration of 20kHz was generated by HSK 63 ultrasonic actuator. The two grinding speeds, 1.67m/s and 3.35m/s, were applied. On the other hand, grinding forces were measured by KISTLER dynamometer.

• 대한금속재료학회지
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• 제47권10호
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• pp.667-674
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• 2009

High temperature wear of STD 61 tool steels sliding against the Al-9%Si coated steels used for hot press forming has been studied in comparison with that of the tool steels sliding against the uncoated steels. Wear tests have been performed using a pin-on-disc configuration under an applied normal load of 50N for 20 min with heating the coated and uncoated steels up to 800$^{\circ}C$. It was found on the worn surface of the STD 61 tool steels sliding against the Al-9%Si coated steels that the formation of the glazed layers containing Al transferred from the coated tribopair may contribute to a reduction of the coefficient of friction, and detachment in part occur due to delamination wear, resulting in higher specific wear rate. On the other hand the Fe-oxide wear debris entrapped on the softer surface of the uncoated steels can act as a tribosurface, leading to decreased adhesive wear of the STD 61 tool steels, resulting in a lower specific wear rate.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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• pp.795-798
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• 1989

This paper presents some results of teleoperation R&D activities for radioactive work. Heavy power manipulator feature is integrated with vision system implementation of advanced type and tool adaptation to hand gripper. Some assodiated te datth activities of interests to the teleoperation and future directions are also presented.

• 한국학교수학회논문집
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• 제4권2호
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• pp.1-9
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• 2001

Since the computer is becoming more and more indispensible tool in every fields of the modern society, it is needed and desirable to utilize the computer as a basic tool from the very early stage of the education process. Recently Maple is gaining its popularity as a comprehensive mathematical software with its power of symbolic calculations and graphics as well as its great numerical computational ability. We demonstrate the suitability of this software as a tool for the mathematical education and presents several examples of the applications of Maple. For the middle and the high school mathematics courses, we give the application examples for the quadratic functions and their graphs, statistics, the three dimensional shapes, algebraic problems. Through the examples, we confirm that mathematical education can be much more effective and simple by using Maple. If we establish computer-assisted mathematical classes, we can draw more attention and excitement from the attendants than traditional classes and eventually improve more rapidly their problem-solving ability On the other hand, the excess of the computer-aided education give to obstacle of psychological, not to be passing over the fact.

• 한국정밀공학회지
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• 제17권4호
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• pp.69-80
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• 2000

Generally, die polishing is a lime consuming process, resulting in 30∼50％ of the whole die manufacturing time. However, die polishing has not been automated yet, since it needs a great deal of experience and skill. This paper describes a new development of automated system for die polishing and focuses on the successful achievements of the element techniques to realize from hand skill to automation, as followings: (1) The 5 axes polishing system by the aid of robot with 2 degrees of freedom, is developed for the application of curved surface die. (2) The CAM system realizes a 5 axes tool path control for polishing and measuring. (3) The conductive elastic tool is able to meet curved surfaces of die and gives a high efficient and quality polishing characteristics. (4) The surface roughness measurement device with noncontact laser is developed and has a high reliability without surface damage.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1130-1131
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• 2006

We found that the """interface reaction between Ni-based alloy bond, diamond, and steel core is very critical in bond strength of diamond tool. None element from metal bond diffuses into the steel core but the Fe element of steel core was easily diffused into the bond. This diffusion depth of Fe has a great effect on the bonding strength. The Cr in steel core accelerated the Fe diffusion and improved the bond strength, on the other hand, carbon decreased the strength. Ni-based alloy bond including Cr was chemically bonded with diamond by forming Cr carbide. However, the Cr and Fe in STS304 were largely interdiffused, the strength was very low. The Cr passivity layer formed at surface of STS304 made worse strength at commissure in brazing process.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2005년도 춘계학술대회 논문집
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• pp.168-173
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• 2005

Composite material is combined with two or more chemical ingredient and different components. FRP has been widely used for the structure of aircraft, ships, automobiles, sporting goods and other machines because of their high specific strength, high specific stiffness and excellent fatigue strength. Recently, the development of machine tool and cutting tool greatly relies on high speed process to satisfy high precision, high efficient machining, shortened process time to maximize material removal rate (MRR) through high cutting speed and feed speed. The research molded CFRP, GFRP as stacking sequence methods of two direction (orientation angle $0^{\circ}\;and\;0^{\circ}/9^{\circ}$) hand lay-up, drilled molded plates using cemented carbide drill and examined chip shapes, surface roughness properties.

• 한국실내디자인학회논문집
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• 제9호
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• pp.24-29
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• 1996

The objectives of this study is to create an environment which students could apply effectively through focused on the innovative methods of education and CAD course contents. The facts which were able to figure out from this study were as follows ; 1. After the analysis of the CAD course contents of the american universities, their common contents were in order of introduce to Computer Aided Drafting and design with Auto CAD/ provide fundamental knowledge of the application for use in design/ examine and how this effects 2 D image and model creation/ CAD as a design tool . Over all trend of CAD course contents of interior design program in american university is moving toward utilizing CAD as a design tool. 2. On the other hand, common contents of our local universities were simply introducing CAD. It means that our course contents are more methodological and theoreatical . And american university's program is focused on problem solving solution as a design tool.