• Title/Summary/Keyword: reliability factors

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A Study on The On-line Detection of the Abnormal State in Drilling. (드릴링시 가공이상상태의 온라인 검출에 관한 연구)

  • 신형곤;박문수;김민호;김태영
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.1038-1042
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    • 2002
  • Monitoring of the drill wear and hole quality change is conducted during the drilling process. Cutting force measured by tool dynamometer is a evident feature estimating abnormal state of drilling. One major difficulty in using tool dynamometer is that the work piece must be mounted on the dynamometer, and thus the machining process is disturbed and discontinuous. Acoustic transducer do not disturb the normal machining process, and provide a relatively easy way to monitor a machining process for industrial application. For this advantage, AE signal is used to estimate the abnormal state. In this study vision system is used to detect flank wear tendency and hole quality, there are many formal factors in hole quality decision circularity, cylindricity, straightness, and so on, but these are difficult to measure in on-line monitoring. The movement of hole center and increasement of hole diameter is presented to determine hole quality As the results of this experiment, AE RMS signal and measurements by vision system are shown the similar tendency as abnormal state of drilling. And detection of the abnormal states using BPNs was achieved 96.4% reliability.

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Development of Sexual Values Scale for College Students (대학생의 성가치관 측정도구 개발)

  • Sung, Kyung Mi;Lee, So Young
    • Journal of the Korean Society of School Health
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    • v.31 no.2
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    • pp.98-107
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    • 2018
  • Purpose: The purpose of this study was to develop an instrument for measuring sexual values of college students. Methods: The data were collected from 308 university students for three months from March 15th to June 15th, 2016. The development of the scale was done in the following order: development of preliminary items; verification of content validity and reliability; factor analysis; and criterion validity of final items. Results: We developed a questionnaire using a five-point Likert-type scale in a self-report form containing 18 items. From the factor analysis, 18 items in three factors were finalized. The 18 items included 3 sub-scales: Cognitive (5 items); Affective (4 items); and Behavioral (9 items). The internal consistency was acceptable (Cronbach's ${\alpha}=.88$). In this study, sexual values were significantly correlated with self-concept (r=.344, p<.001). Conclusion: The results of this study will be useful not only for evaluating sexual values of college students but also for obtaining basic data for sex education. However, we need further studies in order to use the scale in practice and research.

Comparative Investigation of Flavors in Cigarettes by Electronic Nose and GC/MS

  • Lee, Yelin;Park, Jin-Won;Lee, Hwan-Woo;Lee, Seung-Yong;Lee, Hyung-Suk
    • Journal of the Korean Society of Tobacco Science
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    • v.35 no.1
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    • pp.20-27
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    • 2013
  • An Electronic Nose(E-Nose) and Gas Chromatography/Mass Spectroscopy (GC/MS) are meanwhile conventional technique to analyze volatile materials in many industries (e.g., food, medicine, environment) and have broad acceptance in the analysis of tobacco products. In this study, an experiment where tin oxide gas sensor array responses and GC/MS profiles are used to characterize the volatile compounds of different cigarettes at the same time is performed and the measurements of two instruments are compared for cigarette samples with a known chemical information. E-Nose and GC/MS were employed to differentiate and match flavored cigarettes with commercial tobacco flavoring agents (lavender, vanilla, peppermint, orange, star anise). For verifying reliability of two systems, the analyses were conducted in terms of amount of flavors in each cigarettes using partial least squares (PLS) and with the principal components analysis (PCA). Various chemical sensors and GC/MS data was reduced into two principal factors (PC1, PC2) for being distinguished with visualized regions. Both systems provided adequate results for odor characteristics of cigarettes in this study with each instrument having its own advantages and disadvantages.

Advanced Membrane Systems for Seawater Desalination. Kinetics of Salts Crystallization from RO Brines Promoted by Polymeric Membranes

  • Curcio, Efrem;Obaidani, Sulaiman Al;Macedonio, Francesca;Profio, Gianluca Di;Gualtieri, Silvia;Drioli, Enrico
    • Membrane Journal
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    • v.17 no.2
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    • pp.93-98
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    • 2007
  • The reliability of innovative membrane contactors technology (i.e. Gas/Liquid Membrane Contactors, Membrane Distillation/Crystallization) is today increasing for seawater desalination processes, where traditional pressure-driven membrane separation units are routinely operated. Furthermore, conventional membrane operations can be integrated with membrane contactors in order to promote possible improvements in process efficiency, operational stability, environmental impact, water quality and cost. Seawater is the most abundant aqueous solution on the earth: the amount of dissolved salts covers about 3% of its composition, and six elements (Na, Mg, Ca, K, Cl, S) account for more than 90% of ionic species. Recent investigations on Membrane Distillation-Crystallization have shown the possibility to achieve significant overall water recovery factors, to limit the brine disposal problem, and to recover valuable salts (i.e. calcium sulphate, sodium chloride, magnesium sulphate) by combining this technology with conventional RO trains. In this work, the kinetics of $CaSO_4{\cdot}2H_2O,\;NaCl\;and\;MgSO_4{\cdot}7H_2O$ crystallization is experimentally investigated in order to improve the design of the membrane-based crystallization unit.

An Empirical Study on the Performance of the Medium-Sized Distributor's Offsetting Investment and Relationship Commitment with Large-sized Manufacturing Firm in the Marketing Channel (유통경로상의 상쇄투자와 관계결속이 경로구성원의 성과에 미치는 영향)

  • 이수동;이영건
    • Journal of Distribution Research
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    • v.4 no.2
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    • pp.1-20
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    • 1999
  • This study aims to provide distributors with several implications on the channel strategy by testing factors which influence on the offsetting investment. Medium-sized distributor facing a relatively inferior power can cause profit vulnerability from large manufacurer's opportunistic behaviors. At the same time, we tested the relationship commitment to the relation with manufacturer as another alternative strategy taken by medium-sized distributer. For this research, samples from dealers in oil-petroleum refinery industry were selected and the data was collected using mail survey. The data was analyzed utilizing validity test, reliability test, factor analysis, correlation analysis and LISREL. The major analyzed results are as follows: First, the offsetting investment of preventing loss from manufacturer's opportunism didn't affect medium-sized distributor's sales empirically. Second, the hypothesis that the more the medium-sized distributor's transaction specific assets which they invest in the transactional relationship with manufacturer, the more the safeguard against the expected opportunism of manufacturer was not supported by the results. Third, the more use of coercive power by the manufacturer, the more increase in the perception of expected opportunism of manufacturer by the medium-sized distributor, it make stimulates offsetting investment as safeguard by medium-sized distributor and it has negative effect on developing commitment. Finally, the large manufactures dealing with a medium-sized distributor firm which had a reputation of fairness didn't make offsetting investment as a response for distributor's opportunism.

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A Web Based Secure E-Mail System Using the PGP Algorithm (PGP 방식을 이용한 웹 기반 전자우편 보안 시스템)

  • 박동욱;박재희;김진상;김일민
    • The KIPS Transactions:PartC
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    • v.8C no.1
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    • pp.16-22
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    • 2001
  • There are several traditional factors of software quality. Some of them are such as correctness, reliability, efficiency, compatibility, portability, etc. In addition to them, security is required as another factor of software quality nowadays because some application programs are used as a way to attack information systems by stack frame manipulation. Each processor has its own peculiar stack frame mechanism and C language uses the characteristics of them. This paper explains the concept of security problem caused by stack frame manipulation, and the stack frame mechanism of Pentium, Alpha and SP ARC processor in detail. And then it examines the effect of stack frame mechanism on the security of programs in C language.

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A Study on the Effect of Processor Stack Frame Mechanism on Secure Programming in C Language (C 언어에서 프로세서의 스택관리 형태가 프로그램 보안에 미치는 영향)

  • 이형봉;차홍준;노희영;이상민
    • The KIPS Transactions:PartC
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    • v.8C no.1
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    • pp.1-11
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    • 2001
  • There are several traditional factors of software quality. Some of them are such as correctness, reliability, efficiency, compatibility, portability, etc. In addition to them, security is required as another factor of software quality nowadays because some application programs are used as a way to attack information systems by stack frame manipulation. Each processor has its own peculiar stack frame mechanism and C language uses the characteristics of them. This paper explains the concept of security problem caused by stack frame manipulation, and the stack frame mechanism of Pentium, Alpha and SP ARC processor in detail. And then it examines the effect of stack frame mechanism on the security of programs in C language.

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Brand Images of Children's Wear and Mother's Purchase Intention -Focus on Self-Image Congruence and Behavioral Intention Model- (주부가 선호하는 아동복 브랜드의 이미지에 따른 구매의도 -자기일치성과 행동의도모델을 중심으로-)

  • Kim, Ji-Yeon;Lee, Kyu-Hye
    • The Research Journal of the Costume Culture
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    • v.19 no.3
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    • pp.622-636
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    • 2011
  • The purpose of this study was to assess the effects of self-image congruence on attitudes toward purchase intentions of children's clothing via the Behavioral Intention Model. The empirical study was conducted via on-line survey and data were collected from mothers with children aged 6 to 10 years. A total of 593 respondents answered the questionnaire and 574 usable data were statistically analyzed. SPSS 18.0 was used to conduct descriptive statistical analysis, factor analysis, reliability analysis, cluster analysis, Chi-square test, ANOVA, and multiple regressions. A K-means cluster analysis was conducted based on three dimensions brand images of children's wear. Respondents were divided into four groups: elegant image group, multiple image group, ordinary image group, and childlike image group. Characteristics of consumers and clothing evaluative criteria that mothers considered important differed significantly across groups. Moreover, based on these groups, each dimension of self-congruence had different effects on brand attitude. Brand attitude and subjective norms had different effects on purchase intentions. In conclusion, levels of self-congruence and factors influencing purchase intention varied according to brand images of children's wear.

Series Resistance Change by Partial Shading in a-Si Thin Film Photovoltaic(PV) Module (부분 음영에 따른 a-Si Thin Film Photovoltaic(PV) Module의 직렬저항변화)

  • Shin, Jun-Oh;Jung, Tae-Hee;Kim, Tae-Bum;Woo, Sung-Chul;Yun, Na-Ri;Kang, Ki-Hwan;Han, Deuk-Young;Ahn, Hyung-Keun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.23 no.11
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    • pp.901-905
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    • 2010
  • PV module has many power loss factors, and series resistance is the most important elements of them. It is therefore easy to expect the partial shading decrease the lifetime of the semiconductor depletion layer in thin film PV module. Different shading losses could be related with the hot spot which is critical in expecting the reliability issue. In this paper we have modelled the series resistance of the PV module with both different direction of the cell line and shading area of the panel. From the results, thin film a-Si PV module has shown different properties by shading direction.

Cost Analysis for Assessment of Reconstruction Projects (재건축사업의 진단평가를 위한 비용분석)

  • Kwon Dong-Chan;Lee Chan-Sik
    • Proceedings of the Korean Institute Of Construction Engineering and Management
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    • autumn
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    • pp.477-480
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    • 2003
  • The objective procedure and criterion needs to efficiently perform the safety assessment and improve reliability for results of the cost analysis. There are many studies about cost analysis of safety assessment, but the these studies have problems such as non-quantification of criterions and methods. The purpose of this study to suggest the procedure and criterion for successful cost analysis and quantify cost factors. First, in the cost analysis of the housing reconstruction that is presented this study, determinate the life-cycle and the discount rate, then estimate reconstruction cost and remodeling cost. Finally, compare the annual equivalent LCC of two costs for decision malting to reconstruction or remodeling.

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