• Title/Summary/Keyword: empirical research

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Review: Development of Numencal Wave Flume CABMAS-SURF (SUper Roiler Flume for Computer Aided Design of MAritime Structure)

  • Fujima, Koji
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 2002.08a
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    • pp.1-13
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    • 2002
  • For design of maritime structure, it is necessary to evaluate the effect and stability of the structure against wave action. Laboratory model experiments and their empirical formulas are mainly used to estimate those at present, although empirical formulas have a problem of accuracy and hydraulic experiments of cost and duration. In addition, performance-based design, which may be popularized as a new design concept in the near future, requires much more information than that obtained by empirical formulas and laboratory tests. Thus, numerical simulation may become more important hereafter for structure design. (omitted)

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Methodological Challenges of Empirical Studies on Government-Nonprofit Service Delivery: Toward a Dynamic Approach

  • Cho, Sung-Sook
    • Korean System Dynamics Review
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    • v.9 no.1
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    • pp.199-218
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    • 2008
  • Empirical studies have shown that government and human service nonprofit organizations have maintained active partnerships to deliver human services for the past several decades. However, the previous researches on resource dependent government-nonprofit service delivery have revealed serious methodological limitations to adequately demonstrate the dynamic relationship between both sectors over time. Since the dynamics underlying the government-nonprofit service delivery is a complex process, in which multiple factors dynamically interact over time, the assumptions of system dynamics can help improve these methodological drawbacks. This study aims to explore methodological issues and weaknesses observed in empirical studies on resource dependent government-nonprofit service delivery in the United States, and further attempts to provide insights on future research toward a dynamic approach, bringing the assumptions of system dynamics to the challenges of the previous researches.

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An Empirical Research on Relation between FDI and Technology Diffusion: Using Nonstationary Panel Data (외국인 직접투자의 기술확산 효과에 대한 실증분석 : 비안정적 패널자료를 이용하여)

  • Kim Hong-Kee;Kim Jong-Woon
    • Journal of Korea Technology Innovation Society
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    • v.8 no.3
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    • pp.1225-1249
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    • 2005
  • This study aims at investigating whether foreign direct investment plays a role as a channel of international technology diffusion. We used the annual panel data from 1980 to 2002. The nonstationary panel techniques, in particular group mean panel FMOLS(fully modified OLS) was exploited as an empirical methodology in order to tackle the heterogeneity between members and low frequency. The empirical results show that inflow direct investments lead to an increase in total factor productivity and economic growth. Also outflow direct investments contribute to an higher total factor productivity and economic growth. These results confirms that both inflow and outflow direct investments are important channels for international technology diffusion or spillover.

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Empirical modelling of chemically enhanced backwash during ultrafiltration process

  • Daramola, M.O.;Adeogun, A.G.
    • Membrane and Water Treatment
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    • v.2 no.4
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    • pp.225-237
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    • 2011
  • In this study, response of reversibility of membrane flux during chemically enhanced backwash (CEB) to changes in filtration time, filtration flux and coagulant concentration dosing during ultrafiltration (UF) process was investigated using a regression model. The model was developed via empirical modelling approach using response surface methodology. In developing the model, statistically designed UF experiments were conducted and the results compared with the model output. The results showed that the performance of CEB, evaluated in terms of the reversibility of the membrane flux, depends strongly on the changes in coagulant concentration dosage and the filtration flux. Also the response of the reversibility of membrane flux during CEB is independent of the filtration time. The variance ratio, VR << $F_{value}$ and $R^2$ = 0.98 obtained from the cross-validation experiments indicate perfect agreement of the model output with experimental results and also testify to the validity and suitability of the model to predict reversibility of the membrane flux during CEB in UF operation.

An Empirical Study on the Level of Ship Safety Management in View of Seamen's Safety Activity (선원의 안전활동측면에서 본 선박의 안전관리 수준에 관한 실증연구)

  • 임종길
    • Journal of the Korean Institute of Navigation
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    • v.18 no.4
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    • pp.83-118
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    • 1994
  • In this study, the writer embodies factors influencing on ship safety management by an empirical survey. In the empirical survey, the writer used a questionnaire. 1, 271 proper data was obtained from 4, 240 Korean seamen working in 152 domestic and 60 foreign merchant ships. Reliability was tested by Cronbach's Alpha and a conceptual validity by Factor Analysis. Hypotheses established in this study were tested by Correlation and Multiple Regression Analysis. Results of analysis are as follows: Firstly, three levels(i.e. planning, doing, and evaluation) of safety management and satisfaction level of shipboard life correlate significantly with level of ship safety management and between them(P<0.05) Secondly, satisfaction level of shipboard life, evaluation and planning levels of safety management influence significantly on level of ship safety management(P<0.05).

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Impact of Quality Management Practices on Suppliers' Quality Performance: Empirical Evidence from Korean Automotive Parts Suppliers

  • Park, Seung-Wook;Kim, Youn-Sung;Chan, Peng
    • International Journal of Quality Innovation
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    • v.7 no.1
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    • pp.206-222
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    • 2006
  • Recent research on quality management systemically explored the use of quality management practices and performance. The consequences of using quality practices have not been consistently confirmed despite an increasing number of published empirical studies. The results of empirical studies of quality practices and performance are mixed. This study examines which quality management practices indicate high-, medium-, and low-performance under the TQM framework using MANOVA and multiple discriminant analysis (MDA). To measure quality management practices, this study used the Malcolm Baldrige National Quality Award (MBNQA) framework. Based on a survey of 490 suppliers from eleven different industries in Korea, the results revealed that the high performing group surpasses the medium and low performing groups in process management, employee empowerment, employee education and training, and employee satisfaction. Furthermore, the high and medium performing groups exceed the low performing group in human resource planning and evaluation, strategic deployment, leadership system, and senior executive leadership.

Structure And Functions Of District Central Libraries In Tamil Nadu : An Empirical Study

  • Kumar, S.K. Asok;Babu, B. Ramesh
    • Journal of Information Management
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    • v.38 no.4
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    • pp.181-199
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    • 2007
  • This paper aims at projecting the structure and functions of District Central Libraries in Tamil Nadu based upon primary records collected from the Directorate of Public Libraries and survey of District Library officers who are the authorities of District Central Libraries. This paper reveals the State of Art the District Central Libraries and their functions. Based on outputs a number of suggestions have been provided. This paper represents an empirical research study.

An Empirical Analysis of Push-Pull-Mooring Factors Affecting on Switching Intention to Over the Top(OTT) Services (Over The Top(OTT) 서비스 전환의도에 영향을 미치는 Push-Pull-Mooring 요인에 대한 실증적 분석)

  • Park, Hyun Sun;Kim, Sang Hyun
    • The Journal of Information Systems
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    • v.30 no.4
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    • pp.71-94
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    • 2021
  • Purpose The purpose of this study is to verify impacts of factors, representing Push-Pull-Mooring(PPM) on switch intention to OTT(Over-The-Top) service in demand for content and to find relationship between factors through empirical analysis. Design/methodology/approach This study designed a research model by deriving factors affecting the intention to switch on OTT service based on the Push-Pull-Mooring framework and researches on OTT service. To test the hypothesis, a total of 357 responses were collected from individuals with experience in using OTT service and analyzed using SPSS26 and SmartPLS3.0. Findings According to the empirical analysis result, this study confirmed that the push, pull, and mooring factors proposed in this study had a significant effect on switching intention on OTT service. In addition, this study confirmed that both low switching cost and need for variety had a significant effect except for hypothesis H8.

Comparison of wavelet-based decomposition and empirical mode decomposition of electrohysterogram signals for preterm birth classification

  • Janjarasjitt, Suparerk
    • ETRI Journal
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    • v.44 no.5
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    • pp.826-836
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    • 2022
  • Signal decomposition is a computational technique that dissects a signal into its constituent components, providing supplementary information. In this study, the capability of two common signal decomposition techniques, including wavelet-based and empirical mode decomposition, on preterm birth classification was investigated. Ten time-domain features were extracted from the constituent components of electrohysterogram (EHG) signals, including EHG subbands and EHG intrinsic mode functions, and employed for preterm birth classification. Preterm birth classification and anticipation are crucial tasks that can help reduce preterm birth complications. The computational results show that the preterm birth classification obtained using wavelet-based decomposition is superior. This, therefore, implies that EHG subbands decomposed through wavelet-based decomposition provide more applicable information for preterm birth classification. Furthermore, an accuracy of 0.9776 and a specificity of 0.9978, the best performance on preterm birth classification among state-of-the-art signal processing techniques, were obtained using the time-domain features of EHG subbands.

Analysis of the Frailty Model with Many Ties (동측치가 많은 FRAILTY 모형의 분석)

  • Kim Yongdai;Park Jin-Kyung
    • The Korean Journal of Applied Statistics
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    • v.18 no.1
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    • pp.67-81
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    • 2005
  • Most of the previously proposed methods for the frailty model do not work well when there are many tied observations. This is partly because the empirical likelihood used is not suitable for tied observations. In this paper, we propose a new method for the frailty model with many ties. The proposed method obtains the posterior distribution of the parameters using the binomial form empirical likelihood and Bayesian bootstrap. The proposed method yields stable results and is computationally fast. To compare the proposed method with the maximum marginal likelihood approach, we do simulations.