• Title/Summary/Keyword: theoretical research

Search Result 7,438, Processing Time 0.042 seconds

An analysis of research on the determinants of exercise behavior (운동행위 결정요인에 관한 국외문헌 분석)

  • Lee, Jong Kyung
    • Korean Journal of Adult Nursing
    • /
    • v.12 no.3
    • /
    • pp.356-368
    • /
    • 2000
  • The purposes of this study were 1) to identify determinants of exercise behavior 2) to determine theoretical frameworks that were used in other research 3) to investigate the limitations of exercise research. seventy six research papers, published between 1984-1999, were selected by searching Medline for this study. Research subjects, determinants of exercise behavior, exercise measurement, the design of studies, statistical method and theoretical background were examined. The results are as follows. 1. On the research subjects, most research papers studied healthy adults. 2. Thirteen variables were identified that were used more than 5 times in various researches were self efficacy, barrier, social support, benefit, physiological characteristics, habit, personality, intention, health status, motivation, subjective norm, attitude, and affect. The most frequently supported determinant was self efficacy, the second one was social support, the third was affect and so on. But few research papers found any significant relationship between subject norms or attitude and exercise. 3. On exercise measurement, only 22.4% of research papers considered intensity, duration, frequency as elements of exercise, and 64.5% of researches were assessed by self-reported questionnaires. 4. In research design, 80.3% of research papers were survey type research. The most frequently used statistcal method was Regression. 5. 44.8% of research papers were done without any theoretical basis. Based on the above findings the following suggestions are made : 1. Research which includes diverse populations with different levels of health status needs to be studied. 2. Determinants of exercise may be dynamic and varing in their influence, therefore, stages of exercise behavior and processes of change need to be studied. 3. In research design, more prospective, longitudinal studies are needed to identify determinants of exercise habits. 4. It is necessary to develop a reliable, valid exercise measurement tool. 5. Studies are needed to develop a theoretical framework for exercise behavior.

  • PDF

A Theoretical Investigation on Global Expansion of Shipping Companies (해운기업의 국제진출 동기에 대한 이론적 고찰)

  • Jung, Jun-Sik
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
    • /
    • v.44
    • /
    • pp.181-210
    • /
    • 2009
  • This paper discusses global expansion and global strategies of shipping firms. Acknowledging the lack of research on global expansion by freight transport companies, this paper employs the resource-focused model, and explores "why shipping companies emerge" and "why the strategic behaviour of shipping companies is different in the global market". Despite there being a plethora of theoretical and empirical studies on the international operations of business organisations, it is acknowledged that researchers have largely neglected the issues regarding the international expansion within the freight transport industry. Identifying the general lack of contemporary studies concerning the international behaviour of shipping firms, this study addresses the important gap in our knowledge in the theoretical manner. The theoretical analysis suggests that the shipping company's internal resources can be a real reason for the international market participation.

  • PDF

Linking bilinear traction law parameters to cohesive zone length for laminated composites and bonded joints

  • Li, Gang;Li, Chun
    • Advances in aircraft and spacecraft science
    • /
    • v.1 no.2
    • /
    • pp.177-196
    • /
    • 2014
  • A theoretical exploration for determining the characteristic length of the cohesive zone for a double cantilever beam (DCB) specimen under mode I loading was conducted. Two traction-separation laws were studied: (i) a law with only a linear elastic stage from zero to full traction strength; and (ii) a bilinear traction law illustrating a progressive softening stage. Two analytical solutions were derived for the first law, which fit well into two existing solution groups. A transcendental equation was derived for the bilinear traction law, and a graphical method was presented to identify the resultant cohesive zone length. The study using the bilinear traction law enabled the theoretical investigation of the individual effects of cohesive law parameters (i.e., strength, stiffness, and fracture energy) on the cohesive zone length. Correlations between the theoretical and finite element (FE) results were assessed. Effects of traction law parameters on the cohesive zone length were discussed.

THEORETICAL AND EXPERIMENTAL INVESTIGATIONS OF VELOCITY DISTRIBUTIONS FOR ROUND JETS

  • Seo, Il-Won;Mohamed S. Gadalrab;Lyu, Si-wan;Park, Yong-sung
    • Water Engineering Research
    • /
    • v.2 no.2
    • /
    • pp.89-101
    • /
    • 2001
  • The theoretical treatments on jets, in which the flow is issuing into a stagnant medium, have been based on Prandtl's mixing theory. In this study, using Prandtl's mixing length hypothesis, a theoretical relationship for the velocity profile of a single round jet is derived. Furthermore, Gaussian expression is used to approximate the theoretical relationship, in which the Gaussian coefficient is assumed to be decreasing exponentially as the flow goes far from the orifice. Two data sets for a single round jet performed by tow different techniques of measurement are used to verify the suggested relationships. The theoretical and Gaussian distribution give close results in spite of the difference in approach. The observed mean velocity distributions are in good agreements with the suggested theoretical and Gaussian distributions.

  • PDF

The effects of types of knowledge on the performance of fault diagnosis

  • 함동한;윤완철
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • 1995.04a
    • /
    • pp.387-394
    • /
    • 1995
  • With respect to the effectiveness of types of knowledge on human diagnostic performance, the results of several experiments claimed that training with diagnostic rules (procedural knowledge) is more effective than training that provides theoretical knowledge (principle knowledge). However, we usually have the idea that understanding the principles of system dynamics is necessary for diagnosis in some situations. In this study, we pointed out some problems in the previous experiments that force to reinterpret their experimental conclusions. Accordingly, we conducted an experiment to reinvestigate the value of theoretical knowledge in two problem situations. A simulator system, which is named DLD, that is to diagnose an electronic device was created for this purpose. It is a context-free digital logic circuit which includes forty-one gates of three basic types. Our experiment investigated the marginal effects of theoretical knowledge over common diagnostic rules. The experimental results showed that the effectiveness of the instruction in theoretical knowledge is dependent on the complexity of diagnostic situations. This adds up an experimental evidence against the presumed ineffectiveness of theoretical knowledge and forward reasoning in fault diagnosis. Furthermore, the result suggests the source of the use of theoretical knowledge.

  • PDF

Research on Technology, Process, and Strategic Fit of ICT Based Service Model (ICT 기반 융합 서비스 모델의 기술, 프로세스, 전략적 적합 연구)

  • Han, Hyun-Soo;Park, Keun-Young
    • Journal of Information Technology Applications and Management
    • /
    • v.21 no.4
    • /
    • pp.225-245
    • /
    • 2014
  • ICT based convergence application is one of the most prevalent industrial issue these days. Despite of criticalness and potential economic opportunities of the ICT based convergence, theoretical research to analyze the feasibility and estimate the economic impact of the application is rather limited. This paper is intended to fill this research gap. In this respect, we develop theoretical framework to quantitatively estimate the differential benefits of convergent applications, which necessarily include underling ICT technology's contribution attributes extractions, and resulting value increments engendered from user's process effectiveness when ICT based service application is adopted. The research model to assess the differential value of the ICT based service application is developed, grounded on theoretical framework of TPC (Technology-to-performance chain) and contingency fit theories. Scenario based survey method is adopted, and SmartPLS 2.0. is used for statistical analysis of the structural equation model using 312 questionnaire. Valid statistical results are presented to provide useful insight.

Theoretical resistance in cylindrical electrodes with conical tip

  • Hong, Chang-Ho;Kim, Jin-Seop;Chong, Song-Hun
    • Geomechanics and Engineering
    • /
    • v.30 no.4
    • /
    • pp.337-343
    • /
    • 2022
  • The electrical resistivity method is a well-known geophysical method for observing underground conditions, (such as anomalies) and the properties of soil and rock (such as porosity, saturation, and pore fluid characteristics). The shape of electrodes used in an electrical resistivity survey depends on the purpose of the survey and installation conditions. Most electrodes for field applications are cylindrical for sufficient contact with the ground, while some are conically sharpened at their tips for convenient penetration. Previous study only derived theoretical equations for rod-shaped electrodes with spherical tips. In this study, the theoretical resistance for two cylindrical electrodes with conical tips is derived and verified experimentally. The influence of the penetration depth and tip on the measurement is also discussed.

An Exploratory Study on the Success Factors of Research-based Spin-off Venture Across Stages of Growth: Pertaining to Theoretical and Case Study (연구기반 스핀오프 벤처기업의 성장단계별 성공요인에 관한 탐색적 연구: 이론 및 사례 연구를 중심으로)

  • Jung, Gang-Ok
    • Journal of Korea Technology Innovation Society
    • /
    • v.9 no.4
    • /
    • pp.654-687
    • /
    • 2006
  • Research-based spin-off venture, generally formed to commercialize technology originating from public research institution, could contribute to economic wealth creation and regional development. Although there are some interests in research-based spin-off venture and its success factors across stages of growth, little empirical research was done on research-based spin-off venture's success factors in Korea. The purpose of this research is to investigate research-based spin-off venture's success factors across stages of growth. The methodology used is theoretical and case study. Based on theoretical study, it is found that there are four stages of growth in research-based spin-off ventures such as generating business ideas, finalizing new venture projects, launching spin-off firm, and strengthening the creation of economic value. Then, in order to verify them, a case was analyzed focused on success factors across stages of growth. Additionally, implications and limitations of the result of this study are discussed.

  • PDF

Trends of Nursing Research in the Journal of Oncology Nursing (종양간호학회지 논문 내용과 경향 분석;창간호에서 2007년까지)

  • Chung, Bok-Yae;Yi, Myung-Sun;Choi, Eun-Hee
    • Asian Oncology Nursing
    • /
    • v.8 no.1
    • /
    • pp.61-66
    • /
    • 2008
  • Purpose: Purpose of study was to analyze the research articles in the Journal of Korean Oncology Nursing in order to provide an direction for the future research, Methods: This study analyzed 93 studies published in the Journal of Korean Oncology Nursing, from its beginning year to the year 2007, according to the research objectives. The frame of evaluation included years and types of publication, the theoretical frameworks, research design, subject, data collection method, keyword analysis by MeSH. Results: 45.2% of studies was non-degree based studies. 95.7% of studies was not described theoretical framework in the articles. 71.0% was utilized a non-experimental design. 57% of subjects in researches was patients. 76.3% of studies were used the questionnaire for data collection. Concepts as human, nursing, and health were consistently appeared in research. But concepts of environment has been insufficiently conducted. Conclusion: Researches in the Journal of Korean Oncology Nursing has been changed in methodology and the topics of research for the last 7 yr. It progresses in both quantity and quality. But, it is necessary to conduct research founded on theoretical background, various research design, variability of study subjects and topics as supported by scientifically and empirically.

  • PDF

Prediction of Maximum Yields of Metabolites and Optimal Pathways for Their Production by Metabolic Flux Analysis

  • Hong, Soon-Ho;Moon, Soo-Yun;Lee, Sang-Yup
    • Journal of Microbiology and Biotechnology
    • /
    • v.13 no.4
    • /
    • pp.571-577
    • /
    • 2003
  • The intracellular metabolic fluxes can be calculated by metabolic flux analysis, which uses a stoichiometric model for the intracellulal reactions along with mass balances around the intracellular metabolites. In this study, metabolic flux analyses were carried out to estimate flux distributions for the maximum in silico yields of various metabolites in Escherichia coli. The maximum in silico yields of acetic acid and lactic acid were identical to their theoretical yields. On the other hand, the in silico yields of succinic acid and ethanol were only 83% and 6.5% of their theoretical yields, respectively. The lower in silico yield of succinic acid was found to be due to the insufficient reducing power. but this lower yield could be increased to its theoretical yield by supplying more reducing power. The maximum theoretical yield of ethanol could be achieved, when a reaction catalyzed by pyruvate decarboxylase was added in the metabolic network. Futhermore, optimal metabolic pathways for the production of various metabolites could be proposed, based on the results of metabolic flux analyses. In the case of succinic acid production, it was found that the pyruvate carboxylation pathway should be used for its optimal production in E. coli rather than the phosphoenolpyruvate carboxylation pathway.