• Title/Summary/Keyword: reliability factors

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Design of Acceptance Control Charts According to the Process Independence, Data Weighting Scheme, Subgrouping, and Use of Charts (프로세스의 독립성, 데이터 가중치 체계, 부분군 형성과 관리도 용도에 따른 합격판정 관리도의 설계)

  • Choi, Sung-Woon
    • Journal of the Korea Safety Management & Science
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    • v.12 no.3
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    • pp.257-262
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    • 2010
  • The study investigates the various Acceptance Control Charts (ACCs) based on the factors that include process independence, data weighting scheme, subgrouping, and use of control charts. USL - LSL > $6{\sigma}$ that used in the good condition processes in the ACCs are designed by considering user's perspective, producer's perspective and both perspectives. ACCs developed from the research is efficiently applied by using the simple control limit unified with APL (Acceptable Process Level), RLP (Rejectable Process Level), Type I Error $\alpha$, and Type II Error $\beta$. Sampling interval of subgroup examines i.i.d. (Identically and Independent Distributed) or auto-correlated processes. Three types of weight schemes according to the reliability of data include Shewhart, Moving Average(MA) and Exponentially Weighted Moving Average (EWMA) which are considered when designing ACCs. Two types of control charts by the purpose of improvement are also presented. Overall, $\alpha$, $\beta$ and APL for nonconforming proportion and RPL of claim proportion can be designed by practioners who emphasize productivity and claim defense cost.

An Empirical Study on Evaluation for Service Quality in the Fast-Food Shops (패스트푸드점의 서비스품질 평가에 관한 실증적 연구)

  • Han, Dae-Hee;Choi, Yong-Jung
    • Journal of the Korea Society of Computer and Information
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    • v.12 no.5
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    • pp.263-271
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    • 2007
  • With the service industry booming across the world in the 21st century, Korea has been transformed from a manufacturing economy to a service-oriented one. Therefore, the role of service quality has become critical to the success of organizations. Based on the five dimensions (tangibles, reliability, responsiveness, assurance and empathy) of Parasuraman, Zeithaml and Berry(PZB)'s SERVQUAL model, this study is tried to investigate the relationship between the service qualify and customer satisfaction in the Fast-food service industry and analyse the impact of customer satisfaction on the customer's behavior after purchasing. Furthermore, a purpose of this study will help Fast-food industry to detect companies' improvement points(a reform measure) of service quality's factors that have an effect on customer satisfaction in Fast-food service industry.

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Well-Being in Cosmetics (화장품과 웰빙)

  • Kang Hak Hee
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.3 s.47
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    • pp.307-311
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    • 2004
  • In cosmetics industry, we notice that the research should be focused on developing well-being related products such as SPA, esthetique, mass-customization, organics, naturals besides inner beauty and body shaping products. These well-being related products should satisfy customers' expectation about not only concern about health but also safety, reliability, and ethos about products. In that context, the systematic way for well-being related research in cosmetics should be carried out concerning anti-aging with fat-decom-position, vitamin, polyphenol, and organics. At the same time, there are several important factors in this research like augmenting efficacy, controlling skin-absorbency, skin-adaptability, forming, stabilization of activated com-ponents, improving sustainability, and developing new materials based on dermatologic and emotional science. It should be also emphasized that recent technologies such as bio-technology, nano-technology, and natural-material-technology are the cornerstones of developing well-being products.

Design Factor Calculation and Analysis of Grid-Connected Photovoltaic System (계통연계형 태양광발전시스템의 설계계수 산출분석)

  • So, Jung-Hun;Hwang, Hye-Mi;Jung, Young-Seok;Ko, Suk-Whan;Ju, Young-Chul;Lim, Hyun-Mook
    • Journal of the Korean Solar Energy Society
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    • v.33 no.5
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    • pp.89-94
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    • 2013
  • This paper presents a simple but valid design factor calculation method of grid-connected photovoltaic system using normalized yield model. The proposed calculation method can be represented as a quantitative value about five design factors from irradiance to system output power. The validity of this method is identified by analyzing design factor with three years monitored data. These results will indicate that it is useful to determine the optimal design and selection of grid-connected photovoltaic system to meet different user purposes and enhance long-term reliability and stability of grid-connected photovoltaic system.

Development of the Pregnancy Nutrition Knowledge Scale and Its Relationship with Eating Habits in Pregnant Women visiting Community Health Center (임신영양지식 도구개발 및 식습관과의 관련성: 보건소 방문 임부 대상)

  • Kim, Hae-Won
    • Journal of Korean Academy of Nursing
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    • v.39 no.1
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    • pp.33-43
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    • 2009
  • Purpose: This study was done to develop a pregnancy nutrition knowledge scale and to examine the relationships between pregnancy nutrition knowledge and eating habits in pregnant women. Methods: With convenient sampling, 189 pregnant women who used community health centers for their ante-natal care were recruited. Data were collected using a self administered questionnaire including items on pregnancy nutrition knowledge (18 items) developed by researcher and items on eating habits (14 items). Cronbach's alpha and exploratory factor analysis were examined to test reliability and construct validity of the scale. Pearson's correlation coefficients were used to identify the relationship between pregnancy nutrition knowledge and eating habits. Results: Cronbach's alpha of 18 items was .80. In factor analysis using principal components, 6 factors explained 65% of the total variance. The level of pregnancy nutrition knowledge was not sufficient but correlations between pregnancy nutrition knowledge and some of eating habits were significant. Specifically, pregnancy nutrition knowledge was positively correlated with good eating habits and negatively with bad eating habits. Conclusion: The pregnancy nutrition knowledge scale developed in this study is acceptable for nutrition education led by nurses. Pregnancy nutrition knowledge and eating habits are considered as major variables for ante-natal nutrition education. In future studies, explorations are needed on dietary intake and physiological indices in pregnant women, comparison of women at risk with those not at risk, and development of nutritional education programs for pregnant women.

Development of Case Management Activities Inventory in Community Welfare Centers (사회복지관 사례관리 활동목록 개발)

  • Min, So-Young
    • Journal of Digital Convergence
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    • v.15 no.4
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    • pp.489-497
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    • 2017
  • The purpose of this study is to develop case management activities inventory and analyze the perception on case management practice using importance-performance analysis(IPA) in community welfare centers. The comprehensive literature review and the content analysis from the professional scholar and social workers produced 89 items of case management activities items. A survey was conducted to 277 case managers in community welfare centers. The exploratory factor analysis, reliability and validity analysis developed the case management activities inventory comprised of 11 factors and 61 items. Suggestions were made to improve case management practice in community welfare centers.

Effect of Asian Food Neophobia Scale and Food Involvement Scale on Food Choice Motives (아시아인의 푸드네오포비아와 음식관여도가 음식선택동기에 미치는 영향)

  • Kim, Sun-Joo;Lee, Kyung-Hee
    • Journal of the East Asian Society of Dietary Life
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    • v.22 no.2
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    • pp.199-207
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    • 2012
  • Many factors influence food choices and many studies show personal traits that influence food choices, which can be called food neophobia and food involvement. For example, an individual's food-related tastes are thought to certainly influence personal food choices. This study aimed to determine food choice motives, the food neophobia scale (FNS) and food involvement scale (FIS) of Asians staying in or leaving Korea, and the relationship of those personal traits and food choice motives. Subjects (N=370) completed a questionnaire consisting of food choice motives (15 questions), FNS (10 questions), FIS (12 questions) and socio-demographic conditions (10 questions). Items were analyzed to determine the differences according to nationality using ANOVA. Factor analysis and reliability analysis were conducted to identify the indicators of food choice motives. And correlation analysis was conducted to confirm the relationship between food choice motives and food neophobia / food involvement. The result of analysis suggests that food neophobia and food involvement affect food choice motives and that food choice motives are unique to ethnicity and culture.

Rietveld Analysis of Nano-crystalline MnFe2O4 with Electron Powder Diffraction

  • Kim, Jin-Gyu;Seo, Jung-Wook;Cheon, Jin-Woo;Kim, Youn-Joong
    • Bulletin of the Korean Chemical Society
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    • v.30 no.1
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    • pp.183-187
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    • 2009
  • The structure of nano-crystalline $MnFe_2O_4$ was determined and refined with electron powder diffraction data employing the Rietveld refinement technique. A nano-crystalline sample (with average crystal size of about 10.9 nm) was characterized by selected area electron diffraction in an energy-filtering transmission electron microscope operated at 120 kV. All reflection intensities were extracted from a digitized image plate using the program ELD and then used in the course of structure refinements employing the program FULLPROF for the Rietveld analysis. The final structure was refined in space group Fd-3m (# 227) with lattice parameters a=8.3413(7) $\AA$. The reliability factors of the refinement are $R_F$=7.98% and $R_B$=3.55%. Comparison of crystallographic data between electron powder diffraction data and reference data resulted in better agreement with ICSD-56121 rather than with ICSD-28517 which assumes an initial structure model.

Technology Trend of Small Poppet Type Check Valve for Aerospace Application (항공우주용 소형 포펫 체크밸브 기술 동향)

  • Yoo, Jae-Han;Lee, Soo-Yong
    • Current Industrial and Technological Trends in Aerospace
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    • v.9 no.1
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    • pp.158-164
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    • 2011
  • Check valves developed for aerospace applications and commercially available for the applications are investigated. The examples include the ones for launch vehicles, SSME (Space Shuttle Main Engine) and GSE (Ground Support Equipment) purges developed by NASA, requiring high reliability, and the ones by KARI. Also the commercial ones for room and cryogenic temperatures by major valve US companies. Relations of design factors such as seal materials and spring rate to principal performances like operating temperature/pressure and cracking pressure are explained. Then potential operational problems such as chatter and contaminations are explained. Also, filters, fittings for end connections and cleanliness requirements for the applications are considered.

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Guided Missile Initiation Technologies, Now and Tomorrow (유도무기 착화기술의 현황과 발전 전망)

  • 장석태
    • Journal of the Korean Society of Propulsion Engineers
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    • v.4 no.1
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    • pp.102-108
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    • 2000
  • The comparative evaluation/analysis of the initiation technologies currently being used, and the advanced initiation technologies currently being developed lot the aerospace and defense applications was performed. The evaluation criteria used were the compliance, performance, reliability, safety, and cost. The results clearly indicate that there is no one single initiation technology that will satisfy entire spectrum of initiation system requirements. Each initiation system architecture would require different initiation technologies that will satisfy the overall system performance requirements. However, laser initiation, particularly, the laser diode initiation has been getting more attention in recent years. The laser diode initiation, for most part, eliminates EMI and ESD concerns. In addition, laser diode initiation system can also be designed into relatively small packages, are optically connected systems by very light weight cables, are relatively easily designed to meet variety of initiation system requirements. Due to the these compelling factors, laser diode initiation has potential of becoming common initiation systems for many different aerospace and defense application.

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