• 제목/요약/키워드: measurement and modeling

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Measurement of the Device Properties of a Ionization Smoke Detector to Improve Predictive Performance of the Fire Modeling (화재모델링 예측성능 개선을 위한 이온화식 연기감지기의 장치물성 측정)

  • Kim, Kyung-Hwa;Hwang, Cheol-Hong
    • Fire Science and Engineering
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    • v.27 no.4
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    • pp.27-34
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    • 2013
  • The high prediction performance of fire detector models is essentially needed to assure the reliability of fire and evacuation modeling in the process of PBD (Performance Based fire safety Design). The main objective of the present study is to measure input information in order to predict the accurate activation time of smoke detector into a Large Eddy Simulation (LES) fire model such as FDS (Fire Dynamics Simulator). To end this, FDE (Fire Detector Evaluator) which can measure the device properties of detector was developed, and the input information of Heskestad and Cleary's models was measured for a ionization smoke detector. In addition, the activation times of smoke detectors predicted using default values into FDS and measured values in the present study were systematically compared. As a result, the device properties of smoke detector examined in the present study showed a significant difference compared to the default values used into FDS, which resulted in the considerable difference of up to 15 minutes or more in terms of the activation time of smoke detector. The database (DB) on device properties of various smoke and heat detectors will be built to improve the reliability of PBD in future studies.

Study on the Induced Interaction between Groundwater and Surface Water due to the Tunnel Construction (터널 건설에 따른 인근 하천 영향 평가를 위한 연구)

  • 김태희;김영식;하규철;김구영;고동찬;양인제;홍순택
    • The Journal of Engineering Geology
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    • v.14 no.1
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    • pp.81-91
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    • 2004
  • The objective of this study is the evaluation of the tunneling effect on the goundwater-surface water interaction. The designed tunnel line is laid beneath the Hapo-cheon, which runs throughout the study area. And, the pre-evaluation of the tunnel-influence on the Gapo-cheon is urgently needed. However, it is very difficult to find out the similar domestic and/or foreign cases. In this study, the numerical modeling technique was not considered because of the insufficient data. Instead of the numerical modeling, the measurement and analysis of the stream flow rates 5 different points were adopted to evaluate the influence of the tunnel construction on the Gapo-cheon. Based on the analysis of flow monitoring data, it can be concluded that 39% of flow rate in Gapo-cheon is contributed by the groundwater discharge, as baseflow and the construction of tunnel can seriously decrease the flow rate in Gapo-cheon.

Study on Detection of Broken Rail Using Impedance Measurement (임피던스 측정을 통한 레일절손 검지에 관한 연구)

  • Kim, Jae Hee;Ahn, Chi-Hyung
    • Journal of the Korean Society for Railway
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    • v.20 no.2
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    • pp.190-195
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    • 2017
  • This paper proposes a method to detect rail broken through impedance measurement. In general, broken rails are detected in real time using the track circuit, but the proposed method not only detects the broken rails but also estimates positions of broken areas by measuring the rail impedance. To electrically insulate one side of the rail, parallel resonance is made by adding a capacitor; then, the impedance of the other rail is measured. If the measured impedance has an inductive value, there is no broken area of rail. However if the measured impedance has a capacitive value, the rail is broken. The proposed method is modeled using a transmission line; it is shown that the modeling can estimate the position of the broken rail according to the impedance value. The rail impedance is measured by the proposed method for a 60m simple rail model, and it is verified that the presence of a broken rail changes the rail impedance.

Effects of Mothers' Democratic Parenting on Their Children's School Life Adjustment: Mediating Effects of Children's Behavioral Problem and Self-Resilience Perceived by Children (아동이 인식하는 어머니의 민주적 양육태도가 아동의 학교생활적응에 미치는 영향: 아동의 행동문제와 자아탄력성의 매개효과)

  • Kim, Hye Gum
    • Human Ecology Research
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    • v.54 no.5
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    • pp.461-473
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    • 2016
  • The study examined whether children's behavioral problem and self-resilience mediated the association between mothers' democratic parenting and their children's school life adjustment perceived by children. We analyzed data from the fourth Korean Children and Youth Panel Study (KCYPS) that included democratic parenting, behavioral problem, self-resilience, and school life adjustment by 1,971 mothers and fourth grade elementary school children. We identified structural relationships among the variables using SPSS 18.0 and AMOS 18.0 applying structural equation modeling. The measurement model and structure model had a favorable goodness of fit and the results of structure models on each path were as follows. First, school life adjustment had positive correlations with mother's democratic parenting and self-resilience, but there was a negative correlation between school life adjustment and behavioral problems. Second, the relationship between mother's democratic parenting and self-resilience was mediated by behavioral problems and behavioral problems; in addition, self-resilience mediated the relationship between mother's democratic parenting and school life adjustment. The results of this study suggested that children's school life adjustment and children's confidence to control behavioral problems could improve by promoting self-resilience. If fourth grade children could perceive mother's parenting as affection, monitoring children's behavioral problems could be reduced, and children's self-resilience and school life adjustment could be increased.

The Impact of Hallyu 4.0 and Social Media on Korean Products Purchase Decision of Generation C in Vietnam

  • Truong, Nguyen Xuan
    • The Journal of Asian Finance, Economics and Business
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    • v.5 no.3
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    • pp.81-93
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    • 2018
  • This study developed and tested the impact of hallyu 4.0, social media, and consumer ethnocentrism on the decision to purchase Korean products of Generation C in Vietnam. Both qualitative and quantitative methodologies were utilized in this study. Qualitative research was first carried out with in-depth interview, conducted to derive measurement items for the interested constructs. Quantitative research used cross-sectional field design by pilot study and official study. The model was tested and developed using data collected by questionnaires, from a sample of 575 respondents, by both electronic and paper surveys with non-probability and convenience sampling techniques. SPSS 20 and AMOS 20 software were employed to analyze the data. The results of structural equation modeling showed that hallyu 4.0, social media, and consumer ethnocentrism influenced the intermediates variables: subject norms, trust, attitude and behavioral intention and influenced purchase decision. The hallyu 4.0, social media, and consumer ethnocentrism are independent variables. They impact purchase decision through mediating variables such as trust, subjective norms, attitude and behavioral intention. Social media influences not only to trust but also to subjective norms. Subjective norms influence on purchase decision. This study also discovers an interesting fact that trust and attitude variables have an impact on behavioral intention and purchase decision.

An Exploratory Study of IT Adoption Factors' Performance: Considering Internal and External factors in SMEs' ERP (IT 도입요소의 성과에 관한 탐색적 연구: 중소기업 ERP의 내.외부 도입요소를 중심으로)

  • Lee, Jong Moo
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.8 no.4
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    • pp.205-215
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    • 2012
  • Due to a rapid change of business environment, many firms are eager to find the competitiveness by information technology adoption and diffusion. In this exploratory study, we examined the applicability of a previously proposed model to evaluate IT competitiveness based on the innovativeness and verified it's propriety with empirical data. As suggested by previous studies, the proposed model considers a variety of corporate and market characteristics concerned with IT adoption, and it consists of several internal and external impacting factors, which have influence on technology diffusion and its performance. For the empirical analysis, the survey data of domestic ERP adoption cases were adopted from 128 small and medium-sized enterprises(: SMEs) in IT and electrical engineering industry, and analyzed by partial least squares(: PLS) - a popular structural modeling and multivariate projection technique to latent variables. The results indicated positive supports for the research model of external and internal IT adoption factors' influences on innovativeness' performances. However, there are a couple of limitations not to show the reliability of selected measurement items and the generality of model proposed in this exploratory study.

The Structural Relationship among Social Support, Parenting Stress, Self-perception and Parenting Behavior Perceived by Mother (어머니가 지각하는 사회적 지지와 양육스트레스, 자아인식 및 양육행동 간의 구조적 관계)

  • Kim, Hye-Gum;Jo, Hye-Young
    • Journal of Families and Better Life
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    • v.33 no.6
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    • pp.1-14
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    • 2015
  • The purpose of this study was to explore structural relationships among social support, parenting stress, self-perception and parenting behavior perceived by mother and provide preliminary data useful for desirable parenting behavior. For this purpose, the data of fourth wave Panel Study on Korean Children(PSKC) including social support, parenting stress, self-perception and parenting behavior measured by 1,746 mothers with 3-year-old children were analyzed. We identified structural relationships among the variables using SPSS 18.0 and AMOS 18.0 applying structural equation modeling. Measurement model and structure model had favorable goodness of fit and the results of structure models on each path were as follows. First, parenting behavior had positive correlations with social support and self-perception but there was a negative correlation between parenting behavior and parenting stress. Second, the relationship between social support and self-perception was mediated by parenting stress and parenting stress and self-perception mediated the relationship between social support and parenting relationship. In conclusion it is required to raise awareness about the importance of development of various parent education programs and parenting behavior.

Identifying the Consumers Purchasing Fashion Products Designed by Emerging Designers -Focused on the Role of Fashion Innovativeness and Price Sensitivity- (신진 패션 디자이너 제품의 소비자에 대한 고찰 -유행 혁신성과 가격 민감성의 역할을 중심으로-)

  • Shim, Soo In
    • Journal of the Korean Society of Clothing and Textiles
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    • v.41 no.6
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    • pp.1124-1140
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    • 2017
  • The purposes of this study are to (1) explore the characteristics of consumers who purchase products designed by rising fashion designers, and (2) examine the effects of consumer fashion innovativeness and price consciousness on consumer responses toward the products (i.e., product innovativeness, perceived value, and purchase intention). A total of 469 adult consumers aged 19 to 59 responded to an online survey that consisted of a stimulus (i.e., news article introducing new brands of rising fashion designers) and measurement items. As a result, 20% of respondents are found to be customers of rising fashion designers. These buyers (vs. non-buyers) are characterized as female, high income, and high interest toward rising fashion designer products. The findings from structural equation modeling show that fashion innovativeness and price sensitivity have significant, positive effects on product innovativeness and perceived value that further increase purchase intention. These relationships are significant in terms of perceived value dimensions, except for the relationship between social value and purchase intention. Both fashion innovativeness and price sensitivity have significant and positive effects on social, emotional, economical, and functional values. The emotional, economical, and functional values also have significant, positive effects on purchase intention. The implications of these findings are discussed in the conclusion.

Strategic Planning and Firm Performance: The Mediating Role of Strategic Maneuverability

  • KORNELIUS, Hermas;SUPRATIKNO, Hendrawan;BERNARTO, Innocentius;WIDJAJA, Anton Wachidin
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.1
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    • pp.479-486
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    • 2021
  • This study aims to explore the relationships between strategic planning, strategic maneuverability, and firm performance in the current dynamic business environment. It employs a quantitative research method and reports on a survey, using a questionnaire, of service companies in Indonesia's oil and gas industry. Of the 337 companies selected by simple random sampling from a vendor database, responses were received from 70 companies. The analysis was performed using Partial Least Square Structural Equation Modeling and SmartPLS software. The analysis consisted of descriptive statistics, evaluation of the measurement model, evaluation of the structural model, and hypotheses testing. The results show that both strategic planning and strategic maneuverability have a positive relationship with firm performance. In addition, there is a positive relationship between strategic planning and firm performance through the mediating role of strategic maneuverability. The findings suggest that the organizational agility, organizational flexibility, and organizational responsiveness that constitute strategic maneuverability have a positive direct and indirect effect on firm performance, namely financial performance, customer performance, internal process performance, and learning and growth. This study contributes to the strategic management literature and the theory of maneuvers by providing empirical evidence on the relationship between strategic planning, strategic maneuverability, and firm performance.

Performance Expectancy and Effort Expectancy in Omnichannel Retailing

  • RYU, Jay Sang;FORTENBERRY, Sally
    • The Journal of Industrial Distribution & Business
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    • v.12 no.4
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    • pp.27-34
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    • 2021
  • Purpose: While previous studies mainly focus on one shopping expectancy in the context of e-commerce or m-commerce, this study examines the relationship between consumers' performance and effort expectancy and their shopping intentions in the omnichannel retail environment in which both online and offline shopping channels are utilized concurrently in a single shopping journey. Research design, data and methodology: This study measured consumers' performance expectancy, effort expectancy, attitudes, and intentions toward an omnichannel shopping service. A survey was developed using an online survey platform and distributed to U.S. consumers for a 3-week period and 470 usable responses were obtained. The Confirmatory Factor Analysis and Structural Equation Modeling were performed to test the reliability and validity of the measurement model and research model portraying the hypothesized relationships among constructs. Results: The results confirm that both performance and effort expectancy from shopping affected consumers' attitudes toward omnichannel shopping. The positive attitudes increased their omnichannel shopping intentions. Conclusions: Retailers should promote omnichannel strategies as effective shopping tools to improve consumers' shopping experiences and outcomes. This study suggests that retailers should implement omnichannel strategies that synchronize the retail channels they offer and promote the strategies as effective means to enhance customers' shopping outcomes and experiences.