• 제목/요약/키워드: structure improvement

검색결과 4,051건 처리시간 0.037초

선형성 개선과 크기 축소를 위한 새로운 PBG 구조를 이용한 전력증폭기 설계 (Power Amplifier Design using the Novel PBG Structure for Linearity Improvement and Size Reduction)

  • 최재원;서철헌
    • 대한전자공학회논문지TC
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    • 제44권7호통권361호
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    • pp.29-34
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    • 2007
  • 본 논문은 전력증폭기의 크기를 줄이고 선형성을 개선하기 위한 새로운 광전자밴드갭 (PBG) 구조를 제시하였다. 제안된 구조는 비평면 제조 공정을 요구하지 않는 유전체 판위에 패턴을 뜬 2차원의 규칙적인 격자이다. 실험 결과를 통해서 보면, 이 구조는 접지 평면에 세 개의 셀을 식각시킨 기본적인 PBG와 distorted uniplanar compact_PBG (DUC_PBG)보다 더 넓은 저지대역과 더 높은 저지 특성을 갖는다. 이 새로운 PBG 구조는 선형성 개선을 위하여 전력증폭기에 적용되어 질 수 있다. 새로운 PBG 구조를 이용한 전력증폭기의 3차 혼변조 왜곡 (IMD3)은 코드분할 다중접속 (CDMA) 응용에서 -36.16 dBc이다. 제안된 PBG 구조가 없는 전력증폭기와 비교했을 때, 개선된 IMD3는 -13.49 dBc이다.

분리용이성을 고려한 제품의 모듈설계 (Modular design of product considering disassemblability)

  • 목학수;황훈;양태일
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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    • pp.546-549
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    • 2000
  • In this paper, to propose guideline of modular design for improvement of ease of disassembly, product structure must be considered. By analyzing characteristics of structure of subassembly, influencing factor of module can be defined and classified. Based on determination factor of influencing factor of module, criteria for improvement of ease of disassembly can be obtained through the interrelationship between product and process factors.

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수입수산물 검사ㆍ검역제도의 문제점과 정책개선방향 (Korean Inspection System of the Imported Fishing Products : Its Problems and Improvement Directions)

  • 옥영수
    • 수산경영론집
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    • 제26권2호
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    • pp.93-118
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    • 1995
  • The import quantity of the fishing products is very rapidly increasing in the Korea. In the result, the inspection problems are caused to important issues in the fishing products import managements. The major problems of the Korean fishing products inspection are in the system side and structure side. The important improvement schemes are the changement to positive system in the system side, and the unitary in the structure side.

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콘크리트의 표면성능개선이 염소이온투과저항성에 미치는 영향에 관한 실험적 연구 (An experimental study on surface performance improvement of concrete influencing on resistance to chloride)

  • 김재성;강석표;홍성윤
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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    • pp.782-785
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    • 2004
  • Salt attack is one of the serious deterioration factor with respect to the durability of concrete structure. Especially, in case of exposed rebar concrete structure in marine environment, corrosion of rebar is accelerated by penetration of $Cl^-$ from exterior. Through this path, volume of corroded rebar is increased about two and half times due to increased inner pressure originated from rust. As a consequence, the overall deterioration of concrete structure, namely, cracks, reduction of adhesive strength and pop-out is followed. In this paper, the effect of structure treatment of concrete on chloride resistance has been investigated. At the same time, the relationship among several characteristics, such as resistance to chloride, water absorption coefficient and surface hardness of concrete has been investigated. It is believed that surface performance improvement by the application of penetrative hardening agent influences on positively water absorption coefficient, surface hardness of concrete and resistance to chloride ion penetration.

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확장된 ATA 인터페이스의 FPGA구현 (FPGA Inplementation of the Extended ATA Interface)

  • 구대성;김정태;이강현
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 추계종합학술대회 논문집
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    • pp.1037-1040
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    • 1999
  • In this paper, we designed the extended ATA(AT Attachment interface with extension) interface that combines with goods price and ability and intellectual behavior of SCSI, for make progress the ability and structure of ordinary interface for connect with device of using PC. ATA is establish a standard of IDE(Intelligent Drive Electronics) public in small form factor. SCSI bus is device behaving intellectual and have stable hardware structure, calssified instructions structure. But it is device that difficult to buy, because of price of more than two times. The other side, ATA device is worse than SCSI bus in part of ability, but it came to SCSI in part of speed after improve and it's price is less expensive. another improvement of ATA is a standard of ARAP(AT Attachment Packet Interface) and use method of packet transmission and behaves as if SCSI use a method. Finally, improvement of ATAPI behave from interface of only HDD to ability of ordinary interface. This paper propose the structure of extended interface that satisfied the price and ability.

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한국 패션산업의 유통구조 개선에 관한 연구 (A Study for Improvement Distribution Structure of Korean Fashion Industry)

  • 조규회
    • 한국의류학회지
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    • 제18권4호
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    • pp.574-590
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    • 1994
  • The purpose of this research is to provide a plan for improvement distribution structure of Korean fashion industry. This research points out the importance of Korean fashion industry and the change of consumer consciousness which is followed by domestic fashion market and also) this study deals the present condition of fashion distribution industry in Korea, the effects of opening of the distribution structure, the characteristics of domestic's and advanced contries, the problems of them and providing the improvements. 1. Korean fashion industry is needed to change to 'the industry of living culture' 2. Promodern distribution structure in Korean fashion industry has to be turning out to the distribution industry. 3. The returning goods system and buying system of department stores in Korea have to be executed gradually and also the corporation with department stores and fashion organizations are needed. 4. The information system which can make connection from up stream to down stream is needed . 5. It is needed that renovation of technology and development of manpower.

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구조물 동특성 변경을 이용한 실내 부밍 소음 개선 (Improvement of Interior Booming Noise in the Vehicle Using the Structural Dynamic Modification)

  • 김영하;이재웅;김성기
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2012년도 춘계학술대회 논문집
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    • pp.354-359
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    • 2012
  • Improvement of structure-borne noises in the vehicle compartments has been one of the primary concerns in the development of vehicles. The booming is an annoying low frequency interior noise and vibration in vehicle. But it is difficult to reduce the structure-born booming noise in traditional method - trial and error within the shorten development schedule. So in present, the structure dynamic modification (SDM) method helpful to predict the effect of the local mass, stiffness, and damping is introduced. So in order to reduce the interior booming noise, the SDM was performed, and verified with modal test result. It was shown that the interior booming noise was reduced as predicted.

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Improvement of Commercial Silicon Solar Cells with N+-P-N+ Structure using Halogenic Oxide Passivation

  • K. Chakrabarty;D. Mangalaraj;Kim, Kyung-Hae;Park, J.H.;J. Yi
    • Transactions on Electrical and Electronic Materials
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    • 제4권6호
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    • pp.17-20
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    • 2003
  • This paper describes the effect of halogenic gettering during oxide passivation of commercial solar cell with the $N^{+}$-P-$N^{+}$ structure. In order to study the effect of halogenic gettering on $N^{+}$-P-$N^{+}$ structure mono-crystalline silicon solar cell, we performed conventional POCl$_3$ diffusion for emitter formation and oxide passivation in the presence of HCl vapors. The $N^{+}$-P-$N^{+}$ structure based silicon solar cells were found to have higher short circuit current and minority carrier lifetime. Their performance was also found to be superior than the conventional $N^{+}$-P-$N^{+}$ structure based mono-crystalline silicon solar cell. The cell parameters of the $n^{+}$-p-$p^{+}$ and $n^{+}$-p-$n^{+}$ structure based cells, passivated by HCl assisted oxidation were measured. The improvement in $I_{sc}$ was attributed to the effect of the increased diffusion length of minority carriers, which came from the halogenic gettering effect during the growth of passivating oxide. The presence of chlorine caused gettering of the cells by removing the heavy metals, if any. The other advantage of the presence of chlorine was the removal of the diffusion induced (in oxygen environment) stacking faults and line defects from the surfaces of the silicon wafers. All these effects caused the improvement of the minority carrier lifetime, which in-turn helped to improve the quality of the solar cells.

Continuous Improvement Through Integration of Quality Tools

  • He, Zhen;Qi, Ershi;Liu, Zixian
    • International Journal of Quality Innovation
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    • 제3권2호
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    • pp.38-45
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    • 2002
  • Continuous quality improvement is now the focus of research and application in quality engineering. To achieve continuous improvement, it's necessary to integrate quality tools and to plan, design and control the whole process of creating quality. Based on the extensive literature review and the philosophy of concurrent quality engineering, the paper analyzes the relationships among major quality tools such as QFD, FMEA, DOE and SPC and presents a basic model and structure for the integration of quality tools.

안정하도 설계에 따른 물리적 교란개선 평가와 서식적합도 분석 (Physical Disturbance Improvement Evaluation and Habitat Suitability Analysis by Stable Channel Design)

  • 이웅희;최흥식
    • Ecology and Resilient Infrastructure
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    • 제3권4호
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    • pp.285-293
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    • 2016
  • 본 연구는 원주천을 대상으로 하천시설물의 최적 설계를 위한 안정하도 평가와 물리적 교란개선 평가를 수행하였다. 안정하도 설계를 위한 구간별 안정경사를 분석하였으며, 안정경사를 만족하기 위한 하천시설물의 개선 시나리오를 도출하였다. 그에 따라 각 시나리오에 대한 물리적 교란개선 평가를 통해 안정하도 설계와 물리적 교란개선을 위한 최적의 시나리오를 선정하였다. 아울러 안정하도 설계와 물리적 교란개선을 위한 하천시설물의 개선 시 물리 서식처의 변화를 분석하였다. 원주천의 하천 환경조사와 어류의 군집특성을 이용하여 수중 생태계를 대표할 수 있는 복원 목표어종으로 참갈겨니를 선택하였다. 참갈겨니의 서식적합지수를 사용한 서식적합도 분석은 PHABSIM 모형을 이용하였다. 예측 평가를 수행한 결과 서식적합도와 가중가용면적은 소폭 감소하는 것으로 나타났으나, 하천시설물의 개선에 따른 영향은 아닌 것으로 나타났다. 따라서 원주천의 물리적 건전성과 안정성을 제고할 수 있는 하천시설물의 배치 방안을 제시하였으며, 그에 따른 물리 서식처의 변화는 영향이 없는 것을 확인하였다.