• Title/Summary/Keyword: Statistical life time

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Comparison of Electrical Tree Initiation According to Flow Pattern in EHV Power Cable Insulation (초고압 전력 케이블 절연층의 Flow Pattern 방향각에 따른 전기 트리 개시 특성 비교)

  • Lee, Seung-Yoo;Kim, Young-Ho;Cho, Dae-Hee;Lee, In-Ho;Park, Wan-Ki
    • Proceedings of the KIEE Conference
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    • 1999.07d
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    • pp.1532-1534
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    • 1999
  • Electrical treeing phenomenon, regarded as pre-breakdown which accelerates aging process leading an insulation to the complete breakdown, is with no doubt extremely fatal to the performance of the insulation. Investigated in this paper is electrical treeing representing local dielectric failure according to flow pattern, the flow history of liquid polyethylene formed during the extrusion process. Experiments of electrical tree initiation by means of ramp tests were conducted using newly developed electrode system with point-to-point structure. Constant voltage tests were also carried out with the electrode system to estimate the life time of the insulation. Results were analyzed using statistical method such as Weibull distribution.

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The Role Conflict Marital Satisfaction of Married Working Women (취업주부의 역할 갈등과 결혼 만족도에 관한 연구)

  • 임정빈;정혜정
    • Journal of Families and Better Life
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    • v.4 no.1
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    • pp.71-93
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    • 1986
  • The purpose of this study is to identify sevral variables which were assumed to have relationships with the role conflict and marital satisfaction of married working women, and to examine the relationship of the role conflict and marital satisfaction of married working women in Korea. The data for this study was obtained from the survey of the 262 married working women who reside in the city of Seoul employing questionnaire method. Such methods as frequency, percentile, factor analysis, analysis of variance (t-test, F-test), and Pearson's correlation were used for the statistical analysis for this study. The major findings of this study can be summarized as follows; 1) The role conflict level of married working women was related to variables such as age, the number of children, work time, husband's support, job satisfaction, motivation to work outside the home. 2) The overall marital satisfaction was relatively high when they have two children and the presence of household work help. Futhermore, ut was found that marital satisfaction considerably high when husband's support and job satisfaction was highly accorded. 3) The role conflict and marital satisfaction of married working women were significantly negatively correlated.

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Scenario based optimization of a container vessel with respect to its projected operating conditions

  • Wagner, Jonas;Binkowski, Eva;Bronsart, Robert
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.6 no.2
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    • pp.496-506
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    • 2014
  • In this paper the scenario based optimization of the bulbous bow of the KRISO Container Ship (KCS) is presented. The optimization of the parametrically modeled vessel is based on a statistically developed operational profile generated from noon-to-noon reports of a comparable 3600 TEU container vessel and specific development functions representing the growth of global economy during the vessels service time. In order to consider uncertainties, statistical fluctuations are added. An analysis of these data lead to a number of most probable upcoming operating conditions (OC) the vessel will stay in the future. According to their respective likeliness an objective function for the evaluation of the optimal design variant of the vessel is derived and implemented within the parametrical optimization workbench FRIENDSHIP Framework. In the following this evaluation is done with respect to vessel's calculated effective power based on the usage of potential flow code. The evaluation shows, that the usage of scenarios within the optimization process has a strong influence on the hull form.

Analysis of Similarity of Twitter Topic Categories among Regions

  • Yun, Hong-Won
    • Journal of information and communication convergence engineering
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    • v.10 no.1
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    • pp.27-32
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    • 2012
  • Twitter can spread and share all kinds of information such as facts, opinions, and ideas in real time. In this paper, we empirically compare and analyze the topic categories in Twitter with all top 100 users in each of geographic region. We mainly consider the relationships among regions and selected four regions: Global, Seoul, Tokyo, and Beijing. Each of the top 100 users in Twitter is classified into a specific category and then statistical analysis is conducted. Among eight topic categories, the "Arts" category is the largest and the second is "Life". The correlation between global and Seoul groups has the lowest value among the six pairs of relationships between regional groups, and this difference is statistically significant. We find that the Seoul, Tokyo, and Beijing regional Twitter groups, all in East Asia, have high topical similarity. Based on the correlation analysis, Seoul and Tokyo saliently show a sticky trend. The correlation coefficient presents very a strong positive correlation between Seoul and Tokyo. The correlation between the global group and the East Asian groups is relatively lower than that among the East Asian groups.

A Study on De-Identification of Metering Data for Smart Grid Personal Security in Cloud Environment

  • Lee, Donghyeok;Park, Namje
    • Journal of Multimedia Information System
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    • v.4 no.4
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    • pp.263-270
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    • 2017
  • Various security threats exist in the smart grid environment due to the fact that information and communication technology are grafted onto an existing power grid. In particular, smart metering data exposes a variety of information such as users' life patterns and devices in use, and thereby serious infringement on personal information may occur. Therefore, we are in a situation where a de-identification algorithm suitable for metering data is required. Hence, this paper proposes a new de-identification method for metering data. The proposed method processes time information and numerical information as de-identification data, respectively, so that pattern information cannot be analyzed by the data. In addition, such a method has an advantage that a query such as a direct range search and aggregation processing in a database can be performed even in a de-identified state for statistical processing and availability.

Moment Inequalities of NBURFR and NBARFR Classes with Hypotheses Testing Applications

  • Mahmoud, M.A.W.;Alim, N.A.Abdul
    • International Journal of Reliability and Applications
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    • v.4 no.3
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    • pp.141-156
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    • 2003
  • Nonparametric families of aging distributions have been the subject of investigation from long period of time and still. Both probabilistic and statistical properties of these distributions were studied for such families as new better than used renewal failure rate (NBURFR) and new better average renewal failure rate (NBARFR) classes. They have been studied by Abouammoh and Ahmed (1992). In the present work, moment inequalities are derived for the above mentioned families that demonstrate that if the mean life is finite for any of them then all higher order moments exist. Next, based on these inequalities, new test procedures for exponentiality against these families are studied showing that it is simple and hold high relative efficiency for some commonly used alternatives. Dealing with censored data case also studied.

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A Study on the Influence of Environmental Education and Environmental Consciousness to the Environmental Behavior (환경교육과 환경의식이 환경보전 행동에 미치는 영향에 관한 연구)

  • 최남숙
    • Journal of the Korean Home Economics Association
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    • v.32 no.5
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    • pp.29-44
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    • 1994
  • It is an urgent time to give impetus to an ecological understanding of relationship between man and environment and to promote an action to preserve environment. This paper is to examine factors which give influence to environmental education environmental consciousness and environmental behavior of housewives. The subjects of this study are 806 Seoulite housewives. A questionaire is used as the survey method and the statistical methods such as frequency percentage ANOVA multiple regression path analysis have been applied for research. Major findings are summarized as follows: Major findings are summarized as follows: When environmental education program is relatively low differences are shown according to variables of age, education and occupation. Second, when environmental consciousness is high differences are shown according to variables of age education income and housing. Third when environmental behavior is low group difference is shown only according to age. Relative influence to environmental behaviour is shown in the order of spare-life type environmental education environmental consciousness socio-oriented type fashion-oriented type and age difference.

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Metabolomics Approach for Classification of Medicinal Plants

  • Lee, Dong-Ho
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2010.05a
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    • pp.5-5
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    • 2010
  • Selection of specific medicinal sources as well as bioactive compounds is important for the preparation of medicine and related products with good quality. It is necessary to pay close attention for choosing correct medicinal sources, particularly in case of medicinal plants, because of their diversity, which can affect the quality and efficacy of medicine. Discrimination of plants based on morphological or genetic characteristics has been used as a conventional classification method of pharmaceutical sources so far; however, more need demands more general methods for accurate quality assessment of medicinal plants. In this study, ultra performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC/Q-TOF MS) technique applied to this metabolic profiling is a powerful tool due to its higher sensitivity, resolution, and speed compared to conventional HPLC technique. The metabolite profiling of several medicinal plants including Panax ginseng was carried out using UPLC/Q-TOF MS and total metabolites were then subsequently applied to various statistical tools to compare the patterns. The developed metabolomics tool with UPLC/Q-TOF MS successfully identified and classified the samples tested according to their origins.

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A Preliminary Study on the Effectiveness of Cyber Counseling (사이버 상담 활성화를 위한 탐색 연구)

  • 장진경
    • Journal of Families and Better Life
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    • v.20 no.4
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    • pp.135-148
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    • 2002
  • The main purpose of this research was to explore the factors that encourage people to use the cyber counseling in resolving difficulties in their lives. Another purpose of this research was to investigate whether cyber counseling really helps people feel better. For this study, a structured survey questionnaire was distributed both on- and off-line, and 429 respondents returned completed survey forms. The major statistical methods used for data analysis were frequency, factor analysis, 1-test and ANOVA. The results of this study revealed that variables such as gender, age, occupation, internet skills, time of internet use, personality, and the awareness of cyber counseling made a difference in people's use of cyber counseling whenever they felt they needed it. However, cyber counseling seemed to fail to increase feelings of well being in people's lives. The implications of these findings are discussed in this article.

Effect of IceWave® organic nanoscale patches on reduction of musculoskeletal pain

  • Piven, Emily;Dharia, Rupesh;Jones, Karen;Davis, Chuck;Nazeran, Homer
    • CELLMED
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    • v.3 no.1
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    • pp.5.1-5.5
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    • 2013
  • In this pilot dual-site study with LifeWave IceWave$^{(R)}$ patches, using subjects as their own controls, data were acquired from a convenience sample of 16 males and 24 females, 50% Caucasian-Americans, 50% Hispanic-Americans, ages 20 - 85 with neuromuscular pain. The hypothesis was: the application of IceWave$^{(R)}$ patches to the skin will reduce one's perception of pain. Subjects were tested at baseline (without any patches), and then at 1 and 3 h on day 1 and at 1 h on days 2 - 5 after patch application. At every time point, the mean change, indicative of one's perception of pain, was highly significantly (p < 0.0001) reduced, with a statistical power of 100% compared to baseline. Based on these findings, the hypothesis was accepted as true.