• 제목/요약/키워드: high quality factor

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청소년이 지각한 가족응집성, 가족 적응성 및 가족체계 유형이 부모-청소년기자녀관계에 미치는 영향 (The Influence of Adolescent-perceived Family Cohesion, Family Adaptability, and Family System Types on Parent-Adolescent Relationship)

  • 전귀연
    • 대한가정학회지
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    • 제31권3호
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    • pp.157-173
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    • 1993
  • The purpose of this study was to examine the influence of family cohesion, family adaptability, and family system type on parent-adolescent relationship. For this study, adolescents' perceptions of family cohesion, family adaptability, and parent-adolescent relationship quality were utilized. The 443 subjects were selected randomly from the second grade of middle and high schools in the city of Taegu. The survey instruments were AFCESⅢ and CAM/CAF. Factor analysis, Cronbach's α, MANOVA, and Scheff test were conducted for the data analysis. The major findings of this study were as follows: (1) Adolescents who perceived their family as high in cohesion reported the highest quality parent-adolescent relationship in comparison with other levels of cohesion. (2) There were differences in adolescents' evaluations of parent-adolescent relationship quality by their perception of family adapability levels. Namely, adolescents who perceived family adaptability to be low level-i.e. rigid family-showed the relatively severe problems in the parent-adolescent relationship. (3) Adolescents did show some differences by types of family system in their evaluations of parent-adolescent relationship quality. Adolescents reported the highest quality parent-adolescent relationship when they perceived their families as balanced family.

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기상요인과 채취시기가 옻나무 칠액채취량 및 칠액의 質에 미치는 영향 (Effects of Climatic Factors and Tapping Date on Yield and Quality of Lactree (Rhus verniciflua) Sap)

  • 김만조
    • 한국자원식물학회지
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    • 제11권1호
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    • pp.70-79
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    • 1998
  • This study was conducted to understand the effects of weather and tapping date on yield and quality of lactree(Rhus verniciflua) sap yield showed a significant positive correlation with the minimum temperature of one day before sap collection at 1% level and with theminimum humidity of theday of sap collection at 5% level. However, the differences between the maximum and the minimum temperatures and humidities of the day of sap collection were negatively correlated with the sap yield at 5% level. Multiple regression analysis indicated that the minimum temperature of one day bofore sap collection and the minumum humidity of the day sap collection were important factors for increasing sap yield. The high sap yield of lactree by Japanese tapping method was recorded during mid-July and early August. Seasonal variation in lactree sap constituents was observed. The sap collected on 15th of August contained the highest urushiol content (68.3%) and the lowest water content resulting in high quality of lactree sap. By reversed-phase HPLC analysis, fove urushiol components were separated from each other depending on the number of doulbe bonds in the side-chain , and seaxonal variation of urushiol composition was noticed. The 3-C15 triene content fo the sap collected on 5th of July was the highest(77.56%) indicating the major component of urushiol which affects lactree sap quality.

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Improved Power Quality IHQRR-BIFRED Converter Fed BLDC Motor Drive

  • Singh, Bhim;Bist, Vashist
    • Journal of Power Electronics
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    • 제13권2호
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    • pp.256-263
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    • 2013
  • This paper presents an IHQRR (Integrated High Quality Rectifier Regulator) BIFRED (Boost Integrated Flyback Rectifier Energy Storage DC-DC) converter fed BLDC (Brushless DC) motor drive. A reduced sensor topology is derived by utilizing a BIFRED converter to operate in a dual DCM (Discontinuous Conduction Mode) thus utilizing a voltage follower approach for the PFC (Power Factor Correction) and voltage control. A new approach for speed control is proposed using a single voltage sensor. The speed of the BLDC motor drive is controlled by varying the DC link voltage of the front end converter. Moreover, fundamental frequency switching of the VSI's (Voltage Source Inverter) switches is used for the electronic commutation of the BLDC motor which reduces the switching losses in the VSI. The proposed drive is designed for a wide range of speed control with an improved power quality at the AC mains which falls within the recommended limits imposed by international power quality standards such as IEC 61000-3-2.

신선편이 근채류에 대한 소비자 인식도 조사 (Survey on Consumers' Perception of Fresh-cut Root Vegetables)

  • 장민선;김지강;김건희
    • 한국식품조리과학회지
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    • 제26권5호
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    • pp.649-654
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    • 2010
  • This study investigated the recognition of and preference for consumer root vegetables for the improvement of fresh-cut root vegetable quality. The questionnaires consisted of questions on general preference, purchasing locations and quality factors. Answers to 286 questionnaires were analyzed both descriptively and quantitatively using SPSS for Windows (Version 14.0). The principal results were as follows: 37% of the respondents preferred potatoes to other root vegetables; 52% purchased at wholemarket. Most consumers preferred fresh-cut root vegetables; 56% were un-satisfied with fresh-cut vegetables quality as high quality agents. The most considered factor in purchasing fresh-cut root vegetables was shape/appearance.

인터넷 쇼핑몰의 서비스품질이 소비자 만족에 미치는 영향 (Service Quality of Internet Shopping Mall and Consumer Satisfaction)

  • 정경수;박용재
    • 한국정보시스템학회지:정보시스템연구
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    • 제10권1호
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    • pp.173-195
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    • 2001
  • This study is to suggest plans that can make service quality and consumer satisfaction high in internet shopping mall , categorizing the determinants of service quality of Internet shopping mall and analysing determinants of service quality which can give much effect on consumer satisfaction. Using the survey method, the study gathered data from 115 consumers and students with purchasing experience on the web. The Cronbach alpha reliability coefficient was computed to assess the reliability of the responses to all instruments and factor analyses were performed to determine construct validity. Multiple regression was employed to test the hypotheses of this study. According to our findings, the determinants of service quality which influences consumer satisfaction are tangibles, responsiveness, problem solving and security. Several implications of the study are provided in the paper.

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수산물 시장에서 제품과 서비스 품질이 고객만족에 미치는 영향에 관한 연구 (A Study on the Effect of Product and Service Quality on Customer Satisfaction in the Seafood Market)

  • 장춘봉;장영수
    • 수산경영론집
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    • 제41권3호
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    • pp.153-174
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    • 2010
  • In this paper we aim to find out consumer behavior based on fish shares in their buying ingredients, path segmentation, product and service quality, customer satisfaction and then we try to analyze the impact of them on each consumer buying behavior. In this study, first, consumers, divided by general merchandise retail store and traditional fish retail store, these also divided by two groups that are with high spending group and low spending group, so totally we have four parts of consumer behavior segmentation market profiles. Second, we analysis the affect of each factor on consumer behavior. That is, we try to analysis the effect of product and service quality on customer satisfaction in four seafood market group. The results of this study are summarized as follows;

Analysis of Academic Evaluation Indicators Based on Citation Quality

  • Zhang, Mingyue;Shi, Jin;Wang, Jin;Liu, Chang
    • Journal of Information Processing Systems
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    • 제14권4호
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    • pp.916-925
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    • 2018
  • The academic research performance is often quantitatively measured by means of using citation frequency. The citation frequency-based indicators, such as h-index and impact factor, are commonly used reflecting the citation quality to some extent. However, these frequency-based indicators are usually carried out based on the assumption that all citations are equal. This may lead to biased evaluations in that, the attributes of the citing objects and cited objects are significant. A high-accuracy evaluation method is needed. In this paper, we review various citation quality-based evaluation indicators, and categorize them considering the algorithms being applied. We discuss the pros and cons of these indicators, and compare them from four dimensions. The outcomes will be useful for our further research on distinguishing citation quality.

Effects of Pruning on Timber Quality of Pinus koraiensis Grown in Korea

  • Chong, Song-Ho;Jung, Doo-Jin;Park, Byung-Su;Chun, Su Kyoung
    • Journal of the Korean Wood Science and Technology
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    • 제31권6호
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    • pp.22-30
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    • 2003
  • This study was performed to obtain the basic data for high quality timber production and efficient utilization by investigating the effect of pruning on timber quality of domestic plantation-grown Korean pine (Pinus koraiensis Sieb. et Zucc.). The results were summarized as follows:Dead knots (unsound knots) in the pruned logs occurred more at upper parts when compared with in non-pruned ones. The numbers of knots on surface in heavily pruned trees were less than those in non-pruned trees, but there was no significant difference in moderately pruned trees. The required period to reveal clear timber surface without defects after pruning increased proportionally with the increase of knot diameter. The yield of clear lumber production increased by about 10% after 14 years from moderate pruning. The quality grade of log improved with more pruning practices. Knots appeared the most important factor in lowering the log grades.

병렬 연결된 다수의 디지털 구동기를 이용한 High-Q 디지털-아날로그 가변 축전기 (High-Q Micromechanical Digital-to-Analog Variable Capacitors Using Parallel Digital Actuator Array)

  • 한원;조영호
    • 전기학회논문지
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    • 제58권1호
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    • pp.137-146
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    • 2009
  • We present a micromechanical digital-to-analog (DA) variable capacitor using a parallel digital actuator array, capable of accomplishing high-Q tuning. The present DA variable capacitor uses a parallel interconnection of digital actuators, thus achieving a low resistive structure. Based on the criteria for capacitance range ($0.348{\sim}1.932$ pF) and the actuation voltage (25 V), the present parallel DA variable capacitor is estimated to have a quality factor 2.0 times higher than the previous serial-parallel DA variable capacitor. In the experimental study, the parallel DA variable capacitor changes the total capacitance from 2.268 to 3.973 pF (0.5 GHz), 2.384 to 4.197 pF (1.0 GHz), and 2.773 to 4.826 pF (2.5 GHz), thus achieving tuning ratios of 75.2%, 76.1%, and 74.0%, respectively. The capacitance precisions are measured to be $6.16{\pm}4.24$ fF (0.5 GHz), $7.42{\pm}5.48$ fF (1.0 GHz), and $9.56{\pm}5.63$ fF (2.5 GHz). The parallel DA variable capacitor shows the total resistance of $2.97{\pm}0.29\;{\Omega}$ (0.5 GHz), $3.01{\pm}0.42\;{\Omega}$ (1.0 GHz), and $4.32{\pm}0.66\;{\Omega}$ (2.5 GHz), resulting in high quality factors which are measured to be $33.7{\pm}7.8$ (0.5 GHz), $18.5{\pm}4.9$ (1.0 GHz), and $4.3{\pm}1.4$ (2.5 GHz) for large capacitance values ($2.268{\sim}4.826$ pF). We experimentally verify the high-Q tuning capability of the present parallel DA variable capacitor, while achieving high-precision capacitance adjustments.

금코팅 유리관 반사체를 이용한 다이오드 여기 고출력 고효율 Nd:YAG 레이저 (Efficient Diode Pumped High Power Nd:YAG Laser with a Gold Coated Flow Tube)

  • 이종민;문희종;이종훈;한재민;이용주
    • 한국광학회지
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    • 제9권3호
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    • pp.186-190
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    • 1998
  • 직경이 10mm인 유리관의 외벽을 금으로 코팅하여 반사체로 사용되고 최대 출력이 140W인 레이저 다이오드바 (laser diode bar) 3개를 여기 광원으로 이용한 고출력 Nd:YAG 레이저를 설계 제작하였다. 레이저봉의 지름은 6mmdlqu 길이는 130mm이다. 투과율이 11%인 출력경과 전반사경을 사경하여 선형공진기를 구성하고 연속발전시켰을 때 약 130W의 Nd:YNG 레이저 연속출력을 얻었으며 이 때 측정된 기울기 43%, 광변환 효율은 31%에 도달하였다. 레이저빔의 빔질인자(beam quality factor)M2는 최대 다이오드 츨력에서 약85로 관측되었으며 레이저 발진시에 측정한 열렌즈 초점거리의 역수와 여기광의 출력비는 5.3∼7.4D/kWpump 이었다.

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