• Proceedings of the KWS Conference
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• 2002.10a
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• pp.522-527
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• 2002

The microstructure and mechanical properties of friction stir welded OFC plates with 2mm in thickness were examined with the changing welding parameters such as welding speed, rotation speed in this study. The sounding welding conditions was acquired at the optimum welding conditions of the 41mm/min to 61mm/min of welding speed at 1250 rpm of rotation speed. The microstructure of weld zone was divided into four parts such as the base metal region (EM), thermal mechanical affected zone (TMAZ), heat affected zone (HAZ), stir zone (SZ). The grain size in the SZ and the width of weld nugget were increased with increasing welding speed. The hardness profiles of the base metal were distributed about 80HV. The HAZ is a slightly softened region of about 60~75 HV relative to the base metal. The hardness profiles of the SZ were higher than that of base metal. The tensile strength was increased with increasing welding speed. In case increasing rotation speed, tensile strength was decreased. The maximum tensile strength was about 220:MPa which was 110% of joint efficience of that of base metal at 41mm/min of welding speed, 1250rpm of rotation speed.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.113-118
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• 2005

Robots today have wider application fields than they ever have before. They need to work close to humans and fluid and compliable motions are expected of them. This requires redundant degrees of freedom for completing specific task. And conventional motion teaching method cannot be applied to redundant link structures. In this paper, the authors present a proficient, cost-effective and intuitive method for motion teaching. New software to apply this method to a humanoid is also presented. This new method utilizes current sensors to determine which joints to rotate. The experiment shown in this paper is a case of closed link where arms cannot move independently due to the restrictions in between the hands. After the input of several passing points of motion trajectory, the curve fitting is performed by the developed software. This software can insert new points, delete erroneous points and modify existing points. The developed motion teaching method is applied to the Kumdo robot, which is developed by the authors.

• Korean Journal of Computational Design and Engineering
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• v.17 no.5
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• pp.364-374
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• 2012

In this paper, we proposed a data structure to represent structural components of solid rocket motors (SRM) in an automated design program. To propose the data structure, we searched the necessary functions for the automated design program should have. In order to design the structural components of solid rocket motors sufficiently with a design program, it should have the functions to represent the shapes of the components, the drawing and analysis models, the design variables, various product structures, interferences, characteristic properties, design equations, and tightening sets. By modifying the data structure of an element object that is a general purpose data structure to represent a general component of a product, a new data structure was proposed to satisfy all the necessary functions with optimum. Finally, a design program for the structural components of solid rocket motors was developed successfully with the proposed data structure.

• Journal of the Korea Society of Computer and Information
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• v.10 no.5 s.37
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• pp.49-56
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• 2005

Reuse of software is the process of developing software system which does not develop all modules newly but construct system by using existing software modules. Object oriented concept introduces dynamic binding and polymorphism, which increases number of executable Paths. In this case static analysis of source code is not useful to find executable path. These concepts occur new Problems in retesting. Tradition testing method can not cover complex relations such as inheritance, message Passing and instance of and can not apply on object oriented retesting. we propose the method to reduce the number of methods and classes to be retested in associated class relation.

• Journal of Korean Society of Steel Construction
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• v.23 no.3
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• pp.275-282
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• 2011

A recent development of seismic design, which is required among environmentally friendly members, increased the concern on light-weight concrete. Extending around the building, the structural design which is applied for light-weight concrete has been increased. This study therefore evaluates the bending resistance and the shear resistance involved using four specimens that were manufactured and tested. The parameters used in this study exist. This study investigates the structural performance of composite slab using light-weight concrete with KCI (2007).

• 한국HCI학회:학술대회논문집
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• 2007.02a
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• pp.379-385
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• 2007

관성 센서는 외부 장치의 도움 없이 3차원 공간상에서 움직임 측정이 가능하다. 최근 MEMS 기술의 발달로 소형 저가 관성 센서(가속도 센서 혹은 각속도 센서) 제작이 가능해져 관성 센서를 소형 휴대 기기에 내장하여 사용자의 움직임을 감지하거나 의도 파악하는 연구가 진행되고 있다. 본 연구에서는 관성 센서가 내장된 휴대 기기를 이용하여 3차원 공간상에서 6가지 위치에 따라서 각기 다른 6가지 소리를 발생하는 가상의 멀티 타악기 시스템을 제안한다. 즉, 휴대 기기를 상/하로 흔들면 가상 타악기의 타점 위치에 왔을 때 비트 음을 발생하고, 6개의 다른 위치를 구분하여 다른 타점의 위치에서 휴대 기기를 흔들면 각각 그 위치와 미리 지정된 소리가 발생하도록 하였다. 이러한 가상의 멀티 타악기 시스템을 위해서 3차원 공간상에서 실시간으로 사용자의 움직임을 감지하고 휴대 기기의 위치를 파악하는 것이 필요하다. 저가의 관성 센서를 이용하여 사용자가 휴대 기기를 움직이는 동작이 있는 상황에서 실시간으로 휴대 기기의 위치를 추정하는 것은 쉽지 않지만 본 연구에서는 다양한 사용자의 움직임 동작 분석을 통하여 사용자가 가상의 멀티 타악기를 상/하로 흔드는 동작을 감지하고 다른 위치로 이동하는 동작을 구분하였다. 개발된 동작 감지 알고리즘과 위치 구분 알고리즘을 휴대 기기에 적용되어 실제로 가상의 타악기 시스템을 구현하였다.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.142-152
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• 2008

SPT-Uphole method was introduced for the evaluation of near subsurface shear wave velocity (Vs) profile. In SPT-Uphole method, SPT (Standard Penetration Test) which is common in geotechnical site investigation was used as a source and several surface geophones in line were used as receivers. 1D shearwave velocity profile can be obtained in the manner of downhole method, Vs distribution map which is the triangular shape around the boring point can be developed by tomography inversion. To obtain the exact travel time information of shear wave component, a procedure using the magnitude summation of vertical and horizontal components was used based on the evaluation of particle motion at the surface. It was verified that proposed method could give reliable Vs distribution map through the numerical study using the FEM (Finite Element Method) model. Finally, SPT-Uphole method was performed and the feasibility of proposed method was verified in the field.

• Transactions of the Korean hydrogen and new energy society
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• v.20 no.4
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• pp.337-343
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• 2009

Noncatalytic partial oxidation of methane for producing synthesis gas was studied in a lab-scale experimental apparatus. Partial oxidation developed for high-temperature, fuel-rich combustion and it is exothermic process. but Steam reforming and Caron reforming is highly endothermic process to need much energy. Noncatalytic partial oxidation of methane is affected by temperature and equivalent ratio, so we studied effect about composition of synthesis gas at lab scale reactor. We used electronic heater to control the temperature of reactor. The quality of synthesis gas is improved and reduced heat value to require at Noncatalytic partial oxidation because the reacting temperature is lower at oxy condition.

• The Journal of Korean Academic Society of Nursing Education
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• v.13 no.2
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• pp.292-300
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• 2007

Purpose: This study was intended to describe the perception of professors and nurses on clinical practice teaching and organizational integration of colleges and clinical nursing departments. Method: Fifty-three professors of five nursing colleges and eighty-four nurses of one university hospital participated. A structured questionnaire was used for data collection. Result: Disposition for a good clinical instructor was both teaching skill and abundant clinical experience. Professors were competent at adapting nursing process and critical thinking, whereas, nurses were good at clinical skills. Most of the subjects agreed on the organizational integration of nursing colleges and the nursing departments of the hospital, and the proper position for a clinical teacher would be a concurrent instructor. Conclusion: Cooperation between the nursing college and clinical nursing department is needed, and organizational integration of these two is one way for better instruction in clinical practice.

• Korean Journal of Clinical Pharmacy
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• v.19 no.2
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• pp.105-109
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• 2009

In July 2008, The National Police Hospital has developed the CPOE system(Computerized Physician Order Entry system) which links the medicine master and introduced the new program for the injectable antimicrobial agents. After introducing new system, we wanted to check the management of oral antimicrobial agents. Because new system has limitation that new system control only the use of the injectable antimicrobial agents. So we tried to evaluate the use of oral levofloxacin, which was chosen by a medical specialist of the infection. We retrospectively analyzed the appropriateness of oral levofloxacin through EMR(Electric Medical Record) of 72 inpatients who received oral levofloxacin in National Police Hospital in December 2008. We applied the modified ASHP(American Society of Health- System Pharmacists) DUE(Drug Use Evaluation) criteria, which is composed of justification of drug use, critical indicators, complications and outcome measures. Acceptable cases of use of levofloxacin were 67(93.01%) and 57cases(79.2%) showed good outcome. However critical indicators were not performed very well. We want to suggest the new system for the management of the medical therapeutics by the pharmacist in charge.