• 제목/요약/키워드: high quality factor

검색결과 1,923건 처리시간 0.029초

A High Performance Solenoid-Type MEMS Inductor

  • Seonho Seok;Chul Nam;Park, Wonseo;Kukjin Chun
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제1권3호
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    • pp.182-188
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    • 2001
  • A solenoid-type MEMS inductor with a quality factor over 10 at 2 GHz has been developed using an electroplating technique. The integrated spiral inductor has a low Q factor due to substrate loss and skin effects. It also occupies a large area compared to the solenoid-type inductor. The direction of flux of the solenoid-type inductor is parallel to the substrate, which can lower the substrate loss and other interference with integrated passive components. To estimate the characteristics of the proposed inductor over a high frequency range, the 3D FEM (Finite Element Method) simulation is used by using the HFSS at the Ansoft corporation. The electroplated solenoid-type inductor is fabricated on a glass substrate step by step by using photolithography and copper electroplating. The fabrication process to improve the quality factor of the inductor is also developed. The achieved inductance varies within a range from 0.5 nH to 2.8 nH, and the maximum Q factor is over 10.

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의복선택기준에 관한 요인구조분석 -서울시내 주부를 중심으로- (The Factorial Structure Analysis of the Criteria on Clothing Selection)

  • 박은주;이은영
    • 한국의류학회지
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    • 제6권2호
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    • pp.49-55
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    • 1982
  • The purpose of this study was to analyze the factorial structure of the criteria on clothing selection. Data were obtained from 219 housewives in Seoul. 95 likert type questions were selected from the existing questionnaires and from the open end questions. The items were analyzed for discriminating power, followed by the factor analysis. 57 items were subjected to the principal component analysis with orthogonal rotation after extraction of 5 major factors. 47 items were found to be significantly loaded to at least one of the five factors. The factors had the following characteristics: Factor I. The persons scoring high on this factor would invest time and energy in their clothes to achieve their image and individuality. They were interested in clothes, appearance and fashion. Factor II. The persons scoring high on this factor were more concerned about the practicality of clothing, such as ease-of-care, comfort, texture and quality of fabric. They would not select the clothes which soiled easily and would not perform as expected. Factor III. High scores on this factor were associated with the eagerness to get the cloth-ing value for the money. They would make a long plan to buy an expensive clothing and choose a unique clothing regardless of fashion. Factor IV. A high score on this factor was suggestive of modesty. They were willing to buy inconspicuous clothes, such as dark or muted colors, small prints and conservative styles. Factor V. High scores on this factor were characterized by the desire for conformity and approval of their friends. This result may be used to develop an instrument to measure the criteria on clothing selection of consumer.

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A Study on the Perception Level and Proper Management of Indoor Air Quality Recognition in Elderly Care Hospital Workers

  • Choi, Mi-Suk
    • 한국컴퓨터정보학회논문지
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    • 제24권11호
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    • pp.171-178
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    • 2019
  • 본 연구에서는 노인요양병원의 실내공기질 관리계획을 제안하고자 노인요양병원의 실내공기질 수준을 측정하고 근무자의 실내공기질에 대한 인식에 대하여 조사하였다. 측정 항목은 온도, 습도, CO2, CO, PM10, VOC이며 2019년 4월 26일에 실시하였다. 설문 조사에 따르면 실내 공기질에 대한 만족도가 낮을수록 실외 공기질이 더 좋다고 응답하였으며 실내환경 요소 중 악취가 가장 낮은 것으로 응답하였으며 실내 공기질의 만족도가 높을 경우 실내환경 요소의 만족도도 높은 것으로 분석되었다. 다중응답 분석결과 "환기 부족"이었고 회귀 분석 결과 "공기질 관련성" 항목이 가장 낮은 것으로 분석되었다. 노인 요양 병원의 실내 공기질 환경을 최고 수준으로 유지하려면 냄새를 제거하기 위한 환기 장지를 추가로 설치하고 자연 환기 횟수를 늘리고 정기적인 환기담당자를 지정해야 할 것으로 판단된다. 이러한 계획을 수립함으로써 노인요양병원 근무자에게 최상의 서비스를 제공하기 위한 실내 공기질 환경을 제공 할 수 있다.

고온이력이 콘크리트의 강도발현에 미치는 영향에 관한 실험적 연구 (An Experimental Study on the Effects of High temperature Hysteresis on Concrete Strength Development)

  • 김학영;민홍준;장형준;공민호;안무영;정상진
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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    • pp.433-436
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    • 2006
  • This study is basic experiment for estimating influence of strength by curing temperature of concrete's heat of hydration and estimate relationship of compressive strength development by initial curing temperature factor, and then asume temperature factor which influence compressive strength development and for showing basic document of quality control. According to the result of managerial test pieces by the curing temperature factor high-curing temperature shows high strength on 3 day compare with low curing-temperature, shows higher strength than the piece of high curing temperature.

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초기 고온이력을 받은 시멘트 모르타르의 강도 특성에 관한 실험적 연구 (An Experimental Study on the Characteristics of Strength in Mortar under High Temperature conditions in an Early Age)

  • 김영주;김한식;공민호;김제섭;이영도;정상진
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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    • pp.517-520
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    • 2005
  • This study is basic experiment for estimating influence of strength by curing temperature of concrete's heat of hydration and estimate relationship of compressive strength development by initial curing temperature factor, and then asume temperature factor which influence compressive strength development and for showing basic document of quality control. According to the result of cement mortar by the curing temperature factor high-curing temperature shows high strength on 3 day compare with low curing-temperature, shows higher strength than the piece of high curing temperature.

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모르터 압축강도 특성에 영향을 미치는 고온이력에 관한 실험적 연구 (An Experimental Study on the Characteristics of Strength in Mortar under High Temperature conditions in an Early Age)

  • 김영주;공민호;송인명;양동일;백민수;정상진
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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    • pp.703-706
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    • 2004
  • This study is basic experiment for estimating influence of strength by curing temperature of concrete's heat of hydration and estimate relationship of compressive strength development by initial curing temperature factor, and then asume temperature factor which influence compressive strength development and for showing basic document of quality control. According to the result of cement mortar by the curing temperature factor high-curing temperature shows high strength on 3 day compare with low curing-temperature, shows higher strength than the piece of high curing temperature.

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Single-Stage Double-Buck Topologies with High Power Factor

  • Pires, Vitor Fernao;Silva, Jose Fernando
    • Journal of Power Electronics
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    • 제11권5호
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    • pp.655-661
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    • 2011
  • This paper presents two topologies for single-stage single-phase double-buck type PFC converters, designed to operate at high power factor, near sinusoidal input currents and adjustable output voltage. Unlike the known buck type PFC topologies, in which the output voltage is always lower than the maximum input voltage, the proposed converters can operate at output voltages higher than the ac input peak voltage. A reduced number of switches on the main path of the current are another characteristic of the two proposed topologies. To shape the input line currents, a fast and robust controller based on a sliding mode approach is proposed. This active non-linear control strategy, applied to these converters allows high quality input currents. A Proportional Integral (PI) controller is adopted to regulate the output voltage of the converters. This external voltage controller modulates the amplitude of the sinusoidal input current references. The performances of the presented rectifiers are verified with experimental results.

Using Analytic Network Process to Construct Evaluation Indicators of Knowledge Sharing Effectiveness in Taiwan's High-tech Industries

  • Liu, Pang-Lo;Tsai, Chih-Hung
    • International Journal of Quality Innovation
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    • 제9권2호
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    • pp.99-117
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    • 2008
  • High-tech industry has been the principal economic source for Taiwan in recent years. The characteristics of high-tech industries in Taiwan are changeable product markets, short product life cycles and high company attrition rate. In the globalization trend, the high-tech industry has gradually increased corporate competitiveness and reached the goal of sustainable operations through knowledge management, knowledge sharing and new product research and development. Firms have aggressively strengthened and integrated their internal and external resources and enhanced knowledge sharing to increase industry operational performance. Effectively strengthening the knowledge management operation and performance evaluation of knowledge sharing in Taiwan's high-tech industry has become a critical issue. In the selection of knowledge sharing Key Performance Indicators (KPI), this research divided the knowledge sharing indicators into representative strategic indicators such as organizational knowledge learning, organizational knowledge resources, organizational information capacity and organizational knowledge performance through screening using Factor Analysis. The characteristics of the constructs were interdependent. This research calculated and adjusted the correlation among the key performance knowledge sharing indicators using ANP and determined the relative weight of knowledge sharing.

학습자의 측면에서 본 대학 e-러닝 콘텐츠의 질에 영향을 미치는 요인 분석 (Factors Influencing the Quality of E-learning Contents Provided by the Universities at the Learners' Perspectives)

  • 장선영;노석준
    • 인터넷정보학회논문지
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    • 제10권3호
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    • pp.159-172
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    • 2009
  • 본 연구는 학습자의 측면에서 대학 e-러닝 콘텐츠의 질에 영향을 미치는 요인을 밝히고, 대학 e-러닝 콘텐츠의 질을 향상시키기 위한 구체적인 방안을 모색해 보는 데 있다. 이를 위한 구체적인 연구문제들은 다음과 같다: 1) 대학 e-러닝 콘텐츠의 질에 영향을 미치는 요인은 무엇이며, 각 요인에 대한 학습자의 인식(중요도 만족도)은 어떠한가? 2) 대학 e-러닝 콘텐츠의 질에 영향을 미치는 요인별 중요도와 만족도 사이에는 차이가 있는가? 3) 대학 e-러닝 콘텐츠의 질을 향상시키기 위한 구체적인 방안은 무엇인가? 연구대상은 대학에서 e-러닝 강좌를 수강한 경험이 있는 수도권 지역 대학생 543명이었으며, 조사도구는 선행 연구를 토대로 개발된 38개의 문항으로 구성된 설문지를 사용하였다. 자료 분석을 위해 요인분석과 대응표본 t-검증이 사용되었다. 연구 결과, 학습자의 측면에서 본 대학 e-러닝 콘텐츠의 질에 영향을 미치는 요인은 교수전략, 학습내용, 사용성, 평가/피드백, 인터페이스의 다섯 가지로 나타났으며, 모든 요인에서 중요도와 만족도 간에 통계적으로 유의미한 차이가 있었다. 또한 요인별 중요도-만족도 매트릭스 분석 결과, 1) 학습내용은 최소한 현 상태를 지속적으로 유지해야 할 요인으로, 2) 사용성, 교수 전략, 평가/피드백은 상대적으로 중요성은 떨어지지만 여전히 만족도를 높여야 할 요인으로, 그리고 3) 인터페이스는 중요하지만 만족도가 낮아 만족도를 높이기 위한 방안이 시급히 강구되어야 할 요인으로 나타났다. 이러한 연구결과에 기초하여 학습자의 측면에서 대학 e-러닝 콘텐츠의 질을 향상시키기 위한 몇 가지 시사점을 제시하였다.

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자동차용 오디오의 실내음질 평가인자에 관한 연구 (A Study on the Assessment Factors for Car Audio Sound Quaility)

  • 오양기;한명호
    • 소음진동
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    • 제9권5호
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    • pp.991-997
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    • 1999
  • It is getting higher the demand on a good sound in a car. Like some other sensory qualities, achieving a good sound is still treated as a black-box followed by the individual taste of tuning engineers. This study aims to define the attributes of a good car audio sound and the assessment factors affecting the sound quality. With a variety of surveys on professional listening groups and car audio installers, 26 most frequently used vocabularies are selected as typical presentations of car audio sound quality. After repetitions of listening tests with deliberately selected test CD, pre-recorded 15 different digital car-recordings, headphones replay system, and three different listening groups, it is proved that there are at least 5 different assessment factors which significantly affect the car audio sound quality. They are high fidelity, spectral balance, tonal accuracy, sound stage and acoustic fault.

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