• Title/Summary/Keyword: Theoretical Review

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Correlations for Prediction of Non-evaporating Diesel Spray Penetration

  • No, Soo-Young
    • 한국분무공학회지
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    • 제12권3호
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    • pp.146-153
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    • 2007
  • The prediction of diesel spray penetration has been the subject of several works and intensive investigations are still underway by many researchers. It is required to summarize the correlations developed before 1990 days and to introduce the correlations reported recently in the literature. The existing zero-dimensional models for the prediction of diesel fuel spray penetration can be classified as theoretical and empirical correlations. Of various correlations, the models considered in this paper were selected as based on the evaluation results of previous reviews and the recently published works in the literature. The existing theoretical correlations can be classified into seven categories and the existing empirical ones as two categories in this review. According to the review of existing models, the dominating factors for the prediction of spray tip penetration are the spray angle, discharge coefficient, pressure drop across nozzle, ambient density and orifice diameter and time after the start of injection. Especially, the definition for the measurement of spray angle is different with researchers. It is required to evaluate the existing spray tip penetration models for the very high injection pressure and other fuel sprays such as DME. It is also required to evaluate the correlations for the prediction of diesel spray penetration with the connection of liquid-phase penetration.

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중국 "신소매(新零售)"에 관한 연구개발 동향 분석 (Review of the Research & Development of "New Retailing")

  • 무립염;한정수;김형호
    • 한국융합학회논문지
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    • 제10권6호
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    • pp.15-24
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    • 2019
  • 본 연구에서는 "신소매(新零售)"에 대한 연구의 참고자료와 실용적 개발을 위한 지침을 제공하기 위해 "신소매"의 연구현황과 이론적 상황을 정리하였다. "신소매"의 발전은 아직 걸음마 단계에 있다. 이론 연구는 이제 막 시작되어, 보다 실용적인 탐구는 있지만 상대적으로 이론적 연구가 부족한 상황이다. 현재, "신소매"의 이론적 연구와 실천적 발전이 점차 명확해지고 있다. 신소매의 급속한 발전은 신소매에 대한 이론적 연구가 강하게 요구되고 있다. "신소매"의 발전 추세는 대규모화, 경계가 없어지며, 지능화 되고 있다. 연구 결과 "신소매" 하에서의 온라인과 오프라인의 심층적 통합, 새로운 물류체계 및 공급망의 전환과 재편을 가속화 되는 것을 알 수 있었다. '신소매업'의 연구방향에 초점을 맞춰 이론과 실천을 더욱 깊이 연구할 필요가 있다.

팔체질 의학에 대한 논문 리뷰 (Review on Eight Constitution Medicine)

  • 이주호;김희주;신용섭;박영재;박영배
    • 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.

위탁집행형 준정부기관의 혁신과 지식창출에 관한 연구 (Innovation and Knowledge Creation in Commissioned-service-type quasi-governmental Institutions)

  • 이윤석
    • 지식경영연구
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    • 제24권3호
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    • pp.35-52
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    • 2023
  • 본 연구는 혁신에 관한 이론적 논의를 검토하고, 위탁집행형 준정부기관의 특징을 바탕으로 혁신을 위한 방향을 탐색하는데 목적이 있다. 또한 지식창출을 위한 혁신의 주요 내용과 방향성을 탐색함으로서, 위탁집행형 준정부기관 혁신을 위한 방향을 도출하는데 목적이 있다. 혁신과제란 하나의 사업이자 공적 서비스이므로, 서비스의 혁신의 논의를 활용해 혁신과제 유형화를 위한 이론적 검토를 실시하고자 한다. 이론적 틀에 따르면 공공부문 혁신의 시작은 환경 및 사회적 가치의 변화를 탐색하는데서 시작한다. 이 과정을 통해 혁신의 목표와 방향은 물론이고 기관별 핵심역량과 연계된 혁신 과제를 설정하게 된다. 이때 주의할 점은 제도적 조건과 해당 위탁집행형 준정부기관의 특성을 고려해야 한다는 점이다. 결론적으로 이러한 특성을 고려하여, 위탁집행형 준정부기관들은 자신들의 혁신과제 달성을 위한 노력을 확인하고, 자신이 어느 유형에 속하는지 혁신의 추진여건을 진단할 필요가 있다.

방송광고내용규제와 개선방안에 대한 연구 (A Study on the Regulation of Broadcasting Advertising Contents)

  • 김용호
    • 경영과정보연구
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    • 제16권
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    • pp.95-115
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    • 2005
  • Although advertising plays an important role of information source for consumer, also advertising affect negative influence to the consumer and social system. Under the such a concept, this study reviewed the social responsibility of advertising and the freedom of expression including the foreign country's advertising regulation system as the theoretical background of advertising regulation. In addition, this study analyzed the case of the advertisement reviews by Korea Advertising Review Board(august 1, 2000, the business concerning prior deliberation of broadcast advertisements was entrusted to the Korea Advertising Review Board, a civilian self-regulatory body, by the Korean Broadcasting Commission) and Fare Trade Commission. As the result of data analysis, some problems of regulation system and codes are suggested and discussed as follows: (1) the high ratio of rejection (2) using the unnecessary foreign language (3) inconsistency application of deliberation standard.

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Developing a Theory in Academic Research: A Review of Experts’ Advice

  • Dankasa, Jacob
    • Journal of Information Science Theory and Practice
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    • 제3권3호
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    • pp.64-74
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    • 2015
  • Despite the number of developed theories, it still remains a difficult task for some established and emerging scholars in various academic fields to clearly articulate new theories from research studies. This paper reviews and collates the views of scholars on what a theory is and how a good theory can be developed. It explains the concept of a theory, and the different components that make up a theory. The paper discusses the different processes of theory development by emphasizing what theory is and what theory is not. This review found that scholars differ in their definition of a theory, which leads to using terms such as model, paradigm, framework, and theory interchangeably. It found the lack of theoretical constructs in a study to be one of the factors which explains why articles are rejected for publication. This paper may be of benefit to established researchers who may be struggling with theory development, and especially younger academics who are the future of scholarship in various academic fields, particularly in information science.

경관선호와 평가에 있어서 개인적 차이 및 유사성에 대한 이해와 그 중요성에 관한 고찰 (Review on Individual Differences and Similarities in Landscape Preference and Evaluation)

  • 이영경
    • 한국조경학회지
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    • 제22권2호
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    • pp.1-12
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    • 1994
  • This paper reviews and examines the empirical results of past research concerning individual differences and similarities in landscape preference and evaluation. The conflicting results (differences and similarities) found in the review are attributed to the variety of methodology adopted by the past research and to the lack of comprehensive theoretical base in the field of landscape research. Two suggestions are derived from the review. First, both the landscape type to be evaluated and the measurement context to be used by research subjects have critical importance in results. Thus, it is suggested that researchers should be careful in selecting landscape type and measurement tool. Second, more scholartic endeavours should be put into a development of comprehensive theory of landscape experience that could explain both differences and similarities in people's landscape preference and evaluation. Once developed, the theory would not only provide us more valid and specific research methodology, but also allow us to design more healthy and valued landscape.

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노인의 골다공증과 체질량지수의 관계에 관한 이론적 고찰 (Relationship Between Osteoporosis and Body Mass Index among the Elderly: A Theoretical Review)

  • 안경주
    • 가정∙방문간호학회지
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    • 제25권1호
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    • pp.25-36
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    • 2018
  • Purpose: The purpose of this study was to review the literature to explore the relationship between body mass index (BMI) and bone mineral density (BMD) in elderly using an integrative review. Methods: The keywords 'osteoporosis,' 'body mass index,' and 'bone mineral density' were used to search peer-reviewed publications through four databases. Among 1,389 searched articles, eight articles were selected after excluding those that did not meet the inclusion criteria. Results: Seven articles stated that BMI was positively associated with BMD among elderly. In the elderly, the prevalence of osteoporosis was 25-55.7% in women, and 11-13% in men. Conclusion: This study found that high BMI may be helpful to increase BMD among elderly although the mechanism was not clear. It is necessary to identify BMD and fractures in elderly according to body composition in future research.

한국의 가정의사소통연구 대한 고찰 (Review on the Family Communication Research in Korea)

  • 김순옥
    • 가정과삶의질연구
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    • 제7권2호
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    • pp.71-83
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    • 1989
  • This paper reviews research on family communication in Korea. The 51 literatures which had been published till 1988 are used to review. The review includes brief summaries of literatures in methodological issues and research findings classified into five major domains ; theoretical understanding, communication in family relationship, relation to human development, family communication in home management, and the use of family communication in family therapy. Some of the major conclusions may be summarized as follows: 1) Family communication research has short history since it begun in 1973. 2) Research method used in almost the survey research. 3) It is difficult to generalize the research findings because of the short of research and the unexquisiteness of methodology, but is is possible somewhat to understand family communication in Korea.

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Ultrasonic Nondestructive Evaluation(NDE) of Cornposite Materials - A Review -

  • 이억섭
    • 비파괴검사학회지
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    • 제9권2호
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    • pp.25-36
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    • 1989
  • This essay is a general review of the application of ultrasonic NDE techniques to the performance assessment and characterization of composite materials. A brief review of ultrasonic input-output characterization of a composite plate by shear waves is presented. A theoretical development of ultrasonic wave propagation in isotropic and anisotropic media excited, respectively, by a circular transducer and an oscillatory point source is summarized. Some experimental results are described in which ultrasonic velocity and attenuation measurements give insight into material degradation of fatigued composite laminates. Ultrasonic determination of the elastic constants of a composite plate and an experimental attempt at ultrasonic testing of an isotropic plate containing a crack are also included. A recent effort for the characterization of viscoelastic materials using the ultrasonic NDE technique is outlined. Finally, the reliability of ultrasonic NDE is briefly touched upon.

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