• 제목/요약/키워드: time-orientation

검색결과 1,043건 처리시간 0.03초

Co-Fe-Cr 합금도금층의 조성 및 우선방위에 미치는 전해조건의 영향 (The effect electrolysis conditiong on the composition and the preferred orientation of Co-Fe-Cr alloy electrodeposits)

  • 예길촌;문근호
    • 한국표면공학회지
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    • 제31권6호
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    • pp.393-399
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    • 1998
  • The composition and the properred orientation of Co-Fe-Cr alloy electrodeposits were invesigated according to the electrolysis conditions using sulface bath. The current efficiency and the cathode overpotential decrased noticeably with the increase of Cr content in the bath. As the D.C. current density increased increased, the Cr content in the alloy increasd, while Co content decreased and Fe content remained constant, In the pulse current electrolysis, the Cr content of the alloy increased with the mean current density and off-time and then its content increased mord more noticeably with the peak current density than that of D.C. electrolysis. The preferred orientation of the alloy changed from (220)+(111) to (220) with decreasing cathode overpotential.

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동대문시장 이용자의 의복구매유형과 구매행동 (Clothing Purchase Behaviors of Patrons of Dongdaemun Market)

  • 김보경;김미숙
    • 한국의류학회지
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    • 제25권3호
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    • pp.638-649
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    • 2001
  • The purpose of the present study was to investigate the differences in clothing purchase behaviors among the patrons of Dongdaemun market grouped by clothing shopping orientation. A self-administered questionnaire survey was conducted among 600 men and women from ages 15-29 from August 9 to September 12, 1999; 548 were used for the data analysis. Based on the clothing buying orientation, the consumers of Dongdaemun market were divided into four groups: plan circumspected, economy-oriented, fashion-oriented and shopping-oriented. These groups showed significant differences in the selected criteria used for clothing purchase, the amount of money and time spent for shopping. The groups were also significantly different in the usage rate and perceived of the market, and the satisfaction levels with the shopping environments and services of the Dongdaemun Market. With regards to the satisfaction levels, they were showed significant different in the diversity and fashion statement of products, business hours, and advertisement/sales promotion in order. The fashion-oriented group was the highest satisfaction level about the four variables among groups.

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사파이어 기판의 방향에 따른 ZnO 박막의 결정화 거동 (Sapphire orientation dependence of the crystallization of ZnO thin films)

  • 조태식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 하계학술대회 논문집
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    • pp.1036-1038
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    • 2001
  • The sapphire orientation dependence of the crystallization of ZnO thin films has been studied using real-time synchrotron x-ray scattering. The amorphous ZnO thin films with a 2400-${\AA}$-thick were grown on sapphire(110) and sapphire(001) substrates by radio frequency magnetron sputtering at room temperature. The amorphous ZnO films were crystallization into epitaxial ZnO(002) grains both on the sapphire(110) and on the sapphire(001) substrates. The epitaxial quality, such as mosaic distribution and crystal domain size, of the ZnO grains on the sapphire(110) is high, similar to that of the ZnO grains on the sapphire(001). With increasing the annealing temperature to 600$^{\circ}C$, the mosaic distribution and the crystal domain size of ZnO(002) grains in the film normal direction was improved and decreased, respectively.

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유전자 알고리즘을 이용한 광조형장치의 작업변수 결정 (Determining Variables of Fabrication for Stereolithograpy)

  • 전근수;백인환
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 추계학술대회 논문집
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    • pp.910-913
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    • 2000
  • In this research we investigate geometric issues involved while using a particular rapid prototyping system, called Stereolithography(SLA). SLA create prototypes layer by layer, each layer being formed by scanning a laser beam across the x, y surface of a vat of liquid monomer mix. The performance of SLA is influenced by orientation and layer thickness of designed fabrication. The number of layer and the area needed support is influenced by the orientation and layer thickness of designed fabrication. The step influence and volume error is influenced by slice thickness. We minimize the support are, the number of layer and cusp height. These variables of fabrication is minimized using genetic algorithm. The time for genetic algorithm is as little as we can accept. So we calculate support area and cusp height simply.

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엔드밀 가공시 주축 오리엔테이션 기능을 통한 공구마멸측정 보정 장치의 개발 (Development of Calibration Instrument far Tool Wear Measurement using Spindle Orientation Function in End Milling)

  • 강익수;김전하;강명창;김정석;김기태
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.149-153
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    • 2003
  • The most important thing in measuring the tool wear is to set up the measurement base. The end mill that is being used for machining is difficult to set up the base and to measure the tool wear because of geometric properties of that such as a helix and relief angle. In this study, a new instrument using spindle orientation function in end milling is developed to measure tool wear and evaluated by measuring system on the machine. Finally, this new method makes possible the wear measurement of same position and reduces measuring time compared with measuring methods such as the microscope and CCD.

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볼 엔드밀 가공시 공구경로에 따른 절삭특성에 관한 연구 (A Study on Cutting Characteristics According to Cutting Direction in Ball-End Milling)

  • 조병무;이동주
    • 한국공작기계학회논문집
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    • 제16권5호
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    • pp.191-197
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    • 2007
  • Inclined surface milling in the mould and die industries is one of the most commonly needed cutting process. For the variety and complexity of cutting characteristics in various cutting condition, it is difficult to select a optimal tool path orientation. Especially, when the cutting process becomes unstable, it induces self-exited vibrations, a frequent cause of poor tool life, rough surface finish, damage to the workpiece and the machine tool itself, and excessive down time. The comparative results through FFT analysis in this study provide a guideline for the selection tool path orientation.

항만물품공급업의 서비스품질요인이 관계지향성에 미치는 영향에 관한 실증연구 (An Empirical Study on the Service Quality Factors of Port Supply Industry on the Relationship Orientation)

  • 배백식;박남규
    • 수산해양교육연구
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    • 제24권2호
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    • pp.166-179
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    • 2012
  • This study shows how the service quality of port supply industry impacts with customer satisfaction and relationship orientation. Through previous research, service quality of port supply company is considered, at the same time, the key factor of service quality is divided into tangibles, reliability, responsiveness, assurance and empathy. Sample design is based on shipping companies which are registered in Korea Ship owners' Association and Korea Ship managers' Association from Aug. 8 through 26 in 2011. And total of 275 questionnaires are collected from shipping companies in Busan and Kyong nam. Result of this study would be utilized in marketing strategy for port supply industry. In the future research, based on analysis of port supply company's characteristics, the study for port supply industry which are perceived by customers could be conducted.

Al 7075/CFRP 다적층 하이브리드 복합재료의 피로수명에 대한 연구 (A study on fatigue life of Al 7075/CFRP multilayered hybrid composite materials)

  • 윤한기;김연겸;박준수;이경봉
    • 한국해양공학회지
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    • 제10권4호
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    • pp.92-102
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    • 1996
  • In this research, to develope the A1 7075/CFRP multilayered hybrid composites, CRALL(Carbon Reinforced aluminum lamiate) specimens were processed by autoclavecuring system that curing temperature, time, surface pretreatment condition of aluminum were constant. Andthe fatigye life and failure mechanism on CFRP volume fraction and fiber orientation of CRALLspecimens were investigated. A fatigue life was greatly influenced by effect of CFRP fiber volume fraction but it was less effected than those of fiber orientation. The fatigue failure arised from interface delamination of CFRP and aluminum sheet after shear fracture of aluminum layer. The failure mechanism is assumed that the aluminum laminates which divide the CFRP into many thim layers tend to arrest the failure propagation.

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고정밀 병렬평행기구의 자세제어에 관한 연구 (A Study on the Orientation of a High-Precision Stewart Platform)

  • 차영엽;정세미
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1944-1946
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    • 2008
  • This paper analyzed orientation simulation of Stewart platform which is a parallel manipulator of 6-DOF. When platform shape had been given, inverse kinematics as the problem about length of actuator could get an answer using a vector function simply, and forward kinematics as the problem solving shape of platform through the length of actuator could get answer using repetitive and manual explaining Newton-Raphson method because it is expressed a high nonlinear polynomial expression. In addition, for control the Stewart platform it could drive simply and it could confirm the state of orientation in real-time.

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Composition,Dimensional Issue and Nature of Entrepreneurial Orientation (EO) Construct

  • Gupta, Rakesh;Sebastian, V.J.
    • 아태비즈니스연구
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    • 제5권1호
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    • pp.23-31
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    • 2014
  • Entrepreneurship is considered as an important driver of economic growth, new firm creation, business rejuvenation& job creation. Over a period of time research within entrepreneurship literature has shifted from entrepreneur and his personality to his behavioral disposition. This has led to emergence of entrepreneurial orientation (EO) construct, which focuses on the process of entrepreneurship at firm level and it has emerged as the most widely researched area within entrepreneurship field. Though research in this field has been rigorous and exhaustive, still there have been concerns that researchers might have prematurely agreed on the composition, dimensionality, and nature of EO Construct. There has been considerable debate about whether EO Construct comprises three or five dimensions, about co-variance or independence of these dimensions and nature of construct whether formative or reflective. This article builds an argument about the multidimensional nature of EO construct comprising five dimensions, which vary independently and the fact that EO is better explained through formative construct rather than reflective one.

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