• 전자공학회논문지A
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• 제29A권7호
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• pp.39-47
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• 1992

This paper showed that theoretical site attenuation curves were obtained simply by the method of moments analysis for current integral equations on antennas. Since the expansion coefficients of driving and receiving points were calculated from the method of moments procedure, site attenuations were evaluated simply using these basic antenna parameters. Theoretical site attenuations were calculated with half-wave resonant dipoles connected directly to a 50 ohm receiving system and connected to a 72/50 ohm matching network, respectively. Results were compared with other theoretical studies reported so far. Also included were experimental results for site attenuations to prove the validity of theoretical analysis.

• 무역상무연구
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• 제44권
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• pp.181-210
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• 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.

• 종양간호연구
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• 제8권1호
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• pp.61-66
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• 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.

• 시큐리티연구
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• 제2호
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• pp.5-32
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• 1999

Private security will be of great importance in the coming 21st century. In the future, most of the crimes will be violent and frequent. In order to prevent crimes private security must be dealt with in public service area and private area. For this reason, nowadays studies on private security is going on actively. But in reality, serious studies on theoretical backgrounds of private security has not been made yet. Currently, almost all of the theories propose various grounds, such as administrative, economic, and social grounds. And they are based on five backgrounds, that is, profit-oriented enterprise theory, economic reduction theory, vacuum theory, interest group theory, and private management theory. The article furnishes several grounds in addition to these. They are local self-government, management of local self-government, and task-force of guard enterprise. In this article, I am going to present some perspectives in classifying the theories. They are administrative, economic, and social perspective. They are shown as follows by figure. In conclusion, based on theoretical backgrounds mentioned above, private security will be advanced constantly in the future. But in carrying out studies on private security, approaching method of proposing the developmental model is more important than theoretical approaching method.

• Steel and Composite Structures
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• 제26권5호
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• pp.595-606
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• 2018

A calculation method was presented to calculate the deflection of GFRP-concrete-steel beams with full or partial shear connections. First, the sectional analysis method was improved by considering concrete nonlinearity and shear connection stiffness variation along the beam direction. Then the equivalent slip strain was used to take into consideration of variable cross-sections. Experiments and nonlinear finite element analysis were performed to validate the calculation method. The experimental results showed the deflection of composite beams could be accurately predicted by using the theoretical model or the finite element simulation. Furthermore, more finite element models were established to verify the accuracy of the theoretical model, which included different GFRP plates and different numbers of shear connectors. The theoretical results agreed well with the numerical results. In addition, parametric studies using theoretical method were also performed to find out the effect of parameters on the deflection. Based on the parametric studies, a simplified calculation formula of GFRP-concrete-steel composite beam was exhibited. In general, the calculation method could provide a more accurate theoretical result without complex finite element simulation, and serve for the further study of continuous GFRP-concrete-steel composite beams.

• 대한조선학회논문집
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• 제43권1호
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• pp.1-14
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• 2006

To improve maritime safety, it is very important not only to make safer design and operation but also to do proper response in case of maritime casualty. The large-scaled casualties will be caused by loss of structural strength and stability due to the progressive flooding and enlargement of damage by the effect of waves and wind. To prevent foundering and structural failure, the prediction of ship motion behavior of damaged ship in wave is necessary. This paper describes the motion behavior of damaged ship in waves through theoretical and experimental studies. A time domain theoretical model of damaged ship motions and accidental flooding, which can be applied to any type of ship or arrangement and considers the effects of flooding of compartments, has been developed. The model tests have been carried out in regular and irregular waves with different wave heights and directions in ship motion basin. Those were performed for three different damaged conditions such as engine room bottom damage, side shell damage and bow visor damage of a Ro-Ro ship. Comparison of theoretical and experimental results was performed.

• Bulletin of the Korean Chemical Society
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• 제32권4호
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• pp.1187-1194
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• 2011

The hydrogen abstraction reaction of $CF_3CH_2CHO$ + OH has been studied theoretically by dual-level direct dynamics method. Two stable conformers, trans- and cis-$CF_3CH_2CHO$, have been located, and there are four distinct OH hydrogen-abstraction channels from t-$CF_3CH_2CHO$ and two channels from c-$CF_3CH_2CHO$. The required potential energy surface information for the kinetic calculation was obtained at the MCG3-MPWB//M06-2X/aug-cc-pVDZ level. The rate constants, which were calculated using improved canonical transitionstate theory with small-curvature tunneling correction (ICVT/SCT) were fitted by a four-parameter Arrhenius equation. It is shown that the reaction proceeds predominantly via the H-abstraction from the -CHO group over the temperature range 200-2000 K. The calculated rate constants were in good agreement with the experimental data between 263 and 358 K.

• Bulletin of the Korean Chemical Society
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• 제10권6호
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• pp.488-491
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• 1989

Theoretical studies on the proton transfer reaction in a formamide dimer have been done by Ab initio SCF calculation. In this study, we have shown several effects on the potential energy profile of the proton transfer in a formamide dimer, such as the effect of a basis set, the effect of a geometry optimization, and the effect of a distance between proton-donor and proton-acceptor.

• 산업융합연구
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• 제9권1호
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• pp.67-78
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• 2011

It is revealed that there is still considerable interest in job satisfaction and that a growing number of methods are being used to study satisfaction. In particular I reviewed studies using methodologies such as interviews, questionnaires, and diary studies. Overall. my review suggests that working roles change for individuals and theoretical perspectives fade or rise for scholars, the experience of job satisfaction continues to play a central role in understanding life at work.

• 대한한의학회지
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• 제33권1호
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• pp.90-106
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• 2012

Objectives: Eight constitution medicine (ECM), which was first introduced in 1965, has been further developed and refined over the decades, and has consolidated its foundation through many studies on theories, diagnosis and clinical application. However, there have been few reviews on dissertations of ECM. In this study, we reviewed previously published studies related to ECM. Methods: We reviewed a total of 55 ECM-related studies published from 1965 to 2010 found on PubMed and various domestic Oriental medicine journals. Each thesis was classified as a theoretical, diagnostic, or remedy-related study. Results: 1. In the review of theoretical studies, shortly after ECM's introduction in 1965 by Kwon, the authors found studies on constitutional diseases, diets and food table which helped establish the background of ECM. ECM has further developed by comparing its theories with Sasang constitutional medicine, Huang-di-nei-jing, Saam, and Taegeuk acupuncture theories. 2. Research on diagnosis has been focused on its objectivity and accuracy. Constitution could be diagnosed by pulse-taking. To compensate for the lack of accuracy innate in pulse-taking, the Eight Constitution Questionnaire has been invented. 3. Remedies can be largely divided into acupuncture and diet. There were case studies comparing treatment effect of ECM acupuncture to other treatments. Diet related studies were carried out in the fields of immunology and nutrition. Conclusions: The authors reviewed studies that contributed to improved understanding of theories and clinical implications of ECM. Although there were various approaches to its theoretical and clinical grounds, more clinical research is needed. There is also a need to evaluate the accuracy of the experts' diagnoses of the constitution. The relationship between the diet and constitution also needs further research.