• 제목/요약/키워드: Use-dependence

검색결과 567건 처리시간 0.032초

Copula-ARMA Model for Multivariate Wind Speed and Its Applications in Reliability Assessment of Generating Systems

  • Li, Yudun;Xie, Kaigui;Hu, Bo
    • Journal of Electrical Engineering and Technology
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    • 제8권3호
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    • pp.421-427
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    • 2013
  • The dependence between wind speeds in multiple wind sites has a considerable impact on the reliability of power systems containing wind energy. This paper presents a new method to generate dependent wind speed time series (WSTS) based on copulas theory. The basic feature of the method lies in separating multivariate WSTS into dependence structure and univariate time series. The dependence structure is modeled through the use of copulas, which, unlike the cross-correlation matrix, give a complete description of the joint distribution. An autoregressive moving average (ARMA) model is applied to represent univariate time series of wind speed. The proposed model is illustrated using wind data from two sites in Canada. The IEEE Reliability Test System (IEEE-RTS) is used to examine the proposed model and the impact of wind speed dependence between different wind regimes on the generation system reliability. The results confirm that the wind speed dependence has a negative effect on the generation system reliability.

Nalbuphine의 병용투여에 의한 morphine의 내성 및 의존성 형성 저하효과 (The Development of Tolerance to and Dependence on Morphine are Reduced by Co-administration of Nalbuphine in Rat)

  • 정면우;임화경;전용준;김혜정;박인숙;오우용;왕소영;박윤주;강주희
    • 약학회지
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    • 제46권4호
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    • pp.276-282
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    • 2002
  • Morphine has been used widely on the treatment of many types of chronic pain. However the development of tolerance to morphine by repeat application is a major problem in pain therapy. The purpose of the present study was to investigate whether combined administration of nalbuphine with morphine affects the development of tolerance to and dependence on morphine. We hypothesize that the use of nalbuphine, k-agonist may prove to be useful adjunct therapy to prevent morphine-induced undesirable effects in the management of some forms of chronic pain. Morphine (10 mg/kg) was injected to rats intraperitoneally for 5 days. The variable dose of nalbuphine (0.1, 1.0 and 5.0 mg/kg) was administered (i.p.) in combination with morphine injection. The development of tolerance to morphine was assessed by measuring the antinociceptive effect with the Randall-Selitto apparatus. The development of dependence on morphine was determined by the scoring the precipitated withdrawal signs for 20 min after injection of naloxone (10 mg/kg, i.p.). Nalbuphine did not attenuate antinociceptive effect of morphine in rats. Interestingly, combined administration of morphine with nalbuphine (100:1) significantly attenuated the development of morphine tolerance and dependence. These results suggest that the co-administration of nalbuphine with morphine in chronic morphine treatment can be one of therapies to reduce the development of dependence on morphine.

스마트폰에 의존하는 20대 성인의 의존 관련 요인 (Factors Associated with Dependence among Smartphone-Dependent Adults in Their 20s)

  • 박정혜
    • 한국산학기술학회논문지
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    • 제21권6호
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    • pp.366-373
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    • 2020
  • 본 연구의 목적은 스마트폰에 의존하는 20대 성인의 의존 관련 요인을 확인하는 것이다. 본 연구를 위하여 2017년 과학기술정보통신부와 한국정보화진흥원에서 실시한 스마트폰 과의존 실태조사 자료 중 스마트폰에 의존하는 20대, 879명을 분석하였다. 자료분석은 빈도와 백분율, 평균과 표준편차, 독립표본 T 검증, Pearson 상관관계, 다중회귀분석을 사용하였다. 그 결과, 대상자가 가장 많이 사용하는 애플리케이션 유형은 메신저였고, 의존이 심각한 고위험군은 SNS(Social Networking Services), 음악, 게임도 많이 사용하였다. 또한, 의존이 증가할수록 스마트폰 사용빈도가 매우 잦아지고(β=.16, p=.000), 게임(β=.10, p=.028), 웹툰(β=.14, p=.004), SNS(β=.09, p=.047), 금융거래(β=.17, p=.000) 애플리케이션 사용정도가 유의하게 높아졌다. 그러나 대상자들은 의존도가 비교적 낮을 때 자신의 스마트폰 의존에 대해 거의 인식하지 못하였고, 의존이 더욱 심각해진 후 자신이 다른 사람에 비해 좀 더 스마트폰에 의존한다고 인식하였다. 이것은 성인이 스스로 자신의 스마트폰 의존을 인식하기가 쉽지 않음을 의미한다. 그러나 성인이 자신의 문제를 발견하고 해결하는 첫 단계는 문제를 인식하는 것이다. 모든 스마트폰에 자신의 스마트폰 사용행태를 객관적으로 관찰할 수 있는 프로그램을 설치하고 이를 활용할 수 있도록 해야 한다.

유아의 장독립성-장의존성 인지양식에 따른 사회, 인지적 놀이형태에 관한 연구 (Social and Cognitive Play Patterns in Terms of Young Children's Cognitive Styles)

  • 조부경;장선화
    • 아동학회지
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    • 제16권1호
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    • pp.49-64
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    • 1995
  • The purpose of this study was to investigate differences in social play, cognitive play, and social-cognitive play patterns as related to young children's field independence-dependence cognitive styles. Sixteen field independent and sixteen field dependent children were selected from a group of 79 young children with the use of Preschool Embedded Figures Test(PEFT). Their social play, cognitive play, and social-cognitive play patterns were observed. The data collected for this study were analyzed by using SPSS/$PC^+$; frequency, percentage and ${\chi}^2$ test. The results of this study were that (1) difference of social play patterns as related to young children's field independence-dependence cognitive styles was not found, (2) differences were found in cognitive play patterns as related to young children's field independence-dependence cognitive styles, and (3) differences were found in social-cognitive play pattern as related to young children's field independence-dependence cognitive styles.

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불변 및 가변 종속거리를 갖는 루프의 병렬처리를 위한 새로운 동기화 기법 (A New Synchronization Scheme for Parallel Processing of Loop with Constant and Variable Dependence Distance)

  • 이광형;황종선;박두순
    • 전자공학회논문지B
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    • 제32B권5호
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    • pp.693-701
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    • 1995
  • In most application programs, loops usually comprise most of the computation in a program and are the most important source of parallelism. When loops are executed on multiprocessors, the cross iteration data dependences need to be enforced by synchronization between processors. Existing synchronization schemes have been studied mainly on the loop with constant dependence distance. When these schemes are applied to the loop with variable dependence distance, there exists lots of overhead by the use of unnecessary synchronization variables and execution of unuseful synchronization instructions. Even though there exist various variable synchronization schemes, they have a lot of run-time overhead to compute synchronization information. In this paper, we present a new synchronization scheme, Synch-Free/Synch-Hold for managing synchronization efficiently on the loop with constant and variable dependence distance.

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The Environmental Dependence of the Mass-Size Relation for the Most Massive Galaxies

  • Yoon, Yongmin;Im, Myungshin
    • 천문학회보
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    • 제41권1호
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    • pp.69.2-69.2
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    • 2016
  • We study the environmental dependence of the mass-size relation for the most massive early type galaxies (M>$10^{10.7}M_{\odot}$) in the redshift range 0.10~0.15. The sizes of galaxies are measured by non-parametric method. We find that galaxies more massive than $10^{11.1}M_{\odot}$ show the environmental dependence in the mass-size relation. The galaxies with M>$10^{11.1}M_{\odot}$ located in the densest, cluster like environment have larger sizes and extended surface brightness profiles than their counterparts located in a low dense environment. We also find that the environmental dependence of the mass-size relation is more significant for the brightest cluster galaxies (BCGs) than non-BCGs. We use the semi analytic galaxy formation simulation based on the Millennium 1 Simulation for interpretation. Our result can be explained with a hierarchical growth of the most massive galaxies through dissipation-less merger in dense environment.

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중국소비자의 스마트폰 사용 의도에 영향을 미치는 요인 (A Study on the Factors Affecting Chinese Consumers' Smartphone Adoption)

  • 쑨전바오;박미연;황금주
    • Journal of Information Technology Applications and Management
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    • 제20권1호
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    • pp.149-171
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    • 2013
  • The purpose of this study is to investigate factors influencing Chinese consumers' intention to adopt Smartphones. This paper examines Smartphone characteristics factors (situational dependence, diversity and security) and consumer personality characteristics (innovation, self-efficacy and familarity) based on the Technology Acceptance Model. The 320 sets of data are tested against the model using SEM (structural equation model). The research results reveal that diversity and security have significant influences on both perceived usefulness and perceived playfulness. According to the data analysis, self-efficacy affects only perceived easy of use, and familiarity positively affects perceived easy of use, usefulness and playfulness. This study finds that perceived easy of use and perceived usefulness have positive influences on behavioral intention to adopt Smartphones, and situational dependence and innovation directly affect the behavioral intention. The perceived cost has a negative impact on the behavioral intention. Research results are discussed, and limitations of the current study and future research are presented.

Invertebrate Models Used for Characterization of Drug Dependence and Development of Anti-Drug Dependent Agents

  • Chang Hyun-Sook;Kim Ha-Won;Lee Dong-Hee
    • Biomolecules & Therapeutics
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    • 제14권1호
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    • pp.1-10
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    • 2006
  • Drug dependence deals a heavy socioeconomic burden to the society. For adolescents, the damage from drug dependence is greater than adults considering their higher susceptibility to drug effect and increasing chance for violence leading to criminal punishment process. Habitual drug use depends on genetic and environmental factors and the complex interactions between the two. Mammalian model systems have been useful in understanding the neurochemical and cellular impacts of abused drugs on specific regions of the brain, and in identifying the molecular targets of drugs. More elucidation is required whether biological effects of drugs actually cause the habitual dependence at the cellular level. Although there is much insight available on the nature of drug abuse problems, none of the systems designed to help drug dependent individuals is efficient in screening functional ingredients of the drug, and thus resulting in the failure of helping drug dependent individuals recover from drug dependence. Alternative model systems draw the attention of researchers, such as the invertebrate model systems of nematodes (Caenorhabditis elegans) and fruit flies (Drosophila melanogaster). These models should provide new insight into the mechanisms leading to the behavior of drug users (even functional studies analyzing molecular mechanism), and screening useful components to help remove drug dependence among drug users. The relatively simple anatomy and gene expression of the invertebrate model systems should enable researchers to coordinate current knowledge on drug abuse. Furthermore, the invertebrate model systems should facilitate advance in experiments on the susceptibility of specific genetic backgrounds and the interaction between genetic factors to drug dependence.

모바일 오피스 환경에서 이동성(Mobility)이 PDA 활용에 미치는 영향 (Effects of the mobility on the PDA use of Mobile of office environments)

  • 이원준;강윤정;서영주
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2005년도 추계학술대회 및 정기총회
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    • pp.268-296
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    • 2005
  • Given the growing expectations on the value and application of mobile office, we need to understand the factors which affect its successful use and implementation. We in this paper present a parsimonious model which integrates the IS success model and the TAM. The main feature of the model is that it allows one to explore the role of mobility of mobile office systems in determining the level of system usage and dependence. Although mobility is the key property of any mobile system, there is little research effort exerted to understand how mobility affects the traditional IS factors such as perceived ease of use and usefulness. In addition to the system usage, this model also uses dependence as the dependent variable. This is expected to provide richer understanding of the study context. We collected survey data from 1,614 field service workers of a major domestic electronic company. They use PDAs to retrieve information regarding the specifics of the customer service requests and to report what has been done for each service job. The results from SEM analysis show that mobility improves the perceived ease of use which then leads the field service workers to depend more on the PDA systems. Interestingly enough, however, the workers’ satisfaction does not cause more frequent use of the system.

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IoT기반 헬스케어 사용자 경험가치가 사용량과 지속적 사용의도에 미치는 영향에 관한연구 -중국내 샤오미 미밴드 사용자를 중심으로- (The influence of the IoT based healthcare user's experience value on the usage and continuous use intention -Focused on Xiaomi Mi band user in china-)

  • 상맹;신용호;이철우
    • 품질경영학회지
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    • 제44권3호
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    • pp.689-706
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    • 2016
  • Purpose: This study identifies causality in IoT-based healthcare user's experience(playful experience, economical experience), trust, usage, degree of dependence and continuous use intention, especially focused on chinese case. Methods: Face to face interviews was conducted for people who has experience in the use of the Xiaomi Mi band. This study used Partial Least Square(PLS) method with the questionnaires from the interview. Results: IoT-based healthcare users taking playful experience have a strong trust in a positive economic experiences. Also, the user recognizing the experience as an economic one shows stronger intention to use continuously. Conclusion: By getting healthcare users have more economic experience, they have continuous use intention of healthcare product. The empirical findings can be applied to the related companies strategy building.