• Title/Summary/Keyword: Theoretical study

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An Study on the flexural capacity of 'Hybrid Beam' (하이브리드 보의 휨성능에 관한 연구)

  • Hong, Sung-Gul;Yang, Dong-Hyun;Jung, Jong-Hyun;Lim, Byung-Ho
    • Proceedings of the Korea Concrete Institute Conference
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    • 2006.11a
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    • pp.301-304
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    • 2006
  • This study was performed to suggest a theoretical method of flexural capacity of 'Hybrid Beam'. Since the center of 'Hybrid Beam' is composed of embedded composite beam section, a theoretical method of embedded composite beam could be applied to estimation of flexural capacity of 'Hybrid Beam'. In this study, a theoretical evaluation method for flexural capacity of embedded composite beam, which is suggested by KBC 2005, is chosen and its applicability is evaluates as comparing theoretical results with experimental results. In results, for estimation of theoretical ultimate strength, it is proper method that both effects due to concrete and rebar are considered and whole section is assumed to be plastic. and for estimation of theoretical strength at yielding stste, it is proper to apply allowable stress design.

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Theoretical Study of the Relationships between Excited State Geometry Changes and Emission Energies of Oxyluciferin

  • Li, Zhong-Wei;Min, Chun-Gang;Ren, Ai-Min;Guo, Jing-Fu;Goddard, John D.;Feng, Ji-Kang;Zuo, Liang
    • Bulletin of the Korean Chemical Society
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    • v.31 no.4
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    • pp.895-900
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    • 2010
  • In order to find a relationship between firefly luciferases structure and bioluminescence spectra, we focus on excited substrate geometries which may be affected by rigid luciferases. Density functional theory (DFT) and time dependent DFT (TDDFT) were employed. Changes in only six bond lengths of the excited substrate are important in determining the emission spectra. Analysis of these bonds suggests the mechanism whereby luciferases restrict more or less the excited substrate geometries and to produce multicolor bioluminescence.

Experimental and Theoretical Study on the Prediction of Axial Stiffness of Subsea Power Cables

  • Nam, Woongshik;Chae, Kwangsu;Lim, Youngseok
    • Journal of Ocean Engineering and Technology
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    • v.36 no.4
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    • pp.243-250
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    • 2022
  • Subsea power cables are subjected to various external loads induced by environmental and mechanical factors during manufacturing, shipping, and installation. Therefore, the prediction of the structural strength is essential. In this study, experimental and theoretical analyses were performed to investigate the axial stiffness of subsea power cables. A uniaxial tensile test of a 6.5 m three-core AC inter-array subsea power cable was carried out using a 10 MN hydraulic actuator. In addition, the resultant force was measured as a function of displacement. The theoretical model proposed by Witz and Tan (1992) was used to numerically predict the axial stiffness of the specimen. The Newton-Raphson method was employed to solve the governing equation in the theoretical analysis. A comparison of the experimental and theoretical results for axial stiffness revealed satisfactory agreement. In addition, the predicted axial stiffness was linear notwithstanding the nonlinear geometry of the subsea power cable or the nonlinearity of the governing equation. The feasibility of both experimental and theoretical framework for predicting the axial stiffness of subsea power cables was validated. Nevertheless, the need for further numerical study using the finite element method to validate the framework is acknowledged.

Study on Theoretical Models of Regional Humanity Lung Cancer Hazards Assessment

  • Zhang, Chuan;Gao, Xing
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.5
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    • pp.1759-1764
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    • 2015
  • Purpose: To establish the concept of lung cancer hazard assessment theoretical models, evaluating the degree of lung cancer risk of Beijing for regional population lung cancer hazard assessment to provide a basis for technical support. Materials and Methods: ISO standards were used to classify stratified analysis for the entire population, life cycle, processes and socioeconomic management. Associated risk factors were evaluated as lung cancer hazard risk assessment first class indicators. Study design: Using the above materials, indicators were given the weight coefficients, building lung cancer risk assessment theoretical models. Regional data for Beijing were entered into the theoretical model to calculate the parameters of each indicator and evaluate the degree of local lung cancer risk. Results: Adopting the concept of lung cancer hazard assessment and theoretical models for regional populations, we established a lung cancer hazard risk assessment system, including 2 first indicators, 8 secondary indicators and 18 third indicators. All indicators were given weight coefficients and used as information sources. Score of hazard for lung cancer was 84.4 in Beijing. Conclusions: Comprehensively and systematically building a lung cancer risk assessment theoretical model for regional populations in conceivable, evaluating the degree of lung cancer risk of Beijing, providing technical support and scientific basis for interventions for prevention.

Potational Viscous Damping of On-substrate Micromirrors (기판에 인접한 미소거울의 회전 점성감쇠)

  • Kim, Eung-Sam;Han, Ki-Ho;Cho, Young-Ho;Kim, Moon-Uhn
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.50 no.5
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    • pp.243-248
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    • 2001
  • In this paper, we present theoretical and experimental study on the viscous damping of the on-substrate torsional micromirrors, oscillating near the silicon substrates. In this theoretical study, we develop theoretical models and test structures for the viscous damping of the on-substrate torsional micromirrors. From a finite element analysis, we estimate the theoretical damping coefficients of the torsional micromirrors. From a finite element analysis, we estimate the theoretical damping coefficients of the torsional micromirrors, fabricated by the surface-micromaching process. From the electrostatic test of the fabricated devices, frequency-dependent rotationalvelocity of the micromirrors has been measured at the atmospheric pressure using devices, frequency-dependent rotational velocity of the micromirrors has been measured at the atmospheric pressure using the Mach-Zehnder interferometer system. Experimental damping coefficients have been extracted from the least square fit of the measured rotational velocity within the filter bandwidth of 150 kHz. We have compared the theoretical values and the experimental results on the dynamic performance of the micromirrors. The theoretical analysis overstimates the resonant frequency in the amount of 15%, while underestimating the viscous damping in the factors of 10%.

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A Study on the Present Condition of the Coffee and Vision of 21C in Korea (한국 커피시장 현황과 21세기의 비전)

  • 진양호
    • Culinary science and hospitality research
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    • v.5 no.2
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    • pp.5-28
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    • 1999
  • The main propose of this study was to present condition of the Coffee and Vision of 21C in Korea. To achieve the propose of this study, Theoretical and empirical approaches were used. In review of theoretical background, basic concepts and characteristics of Coffee. Based on the theoretical studies and previous studies, vision of 21C in Korea. First, we'll have to a national enterprise of coffee. Second, Instant coffee was export to china and east asia in 21C. Third, our Coffee culture was diversity, so wording is more easy. Fourth, coffee meeting will prosper

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Practical Limitations of Theoretical Acceptance Sampling (이론 샘플링 검사의 실무적 한계)

  • Choe, Seong-Un
    • Proceedings of the Safety Management and Science Conference
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    • 2011.11a
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    • pp.205-211
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    • 2011
  • The papaer reviews four theoretical acceptance sampling plans as OC(Operating Characteristics) curve based inspection, rectifying inspection, switching inspection, and continuous inspection. In addition, the study presents practical limitations of theoretical acceptance sampling by attribute and by variable. Finally, following research also recommends the sampling inspection based on production technology. However, the inspection method requires quality expertise with various experience and implicit knowledge of the field.

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The three most significant contributions of criminological theories to our theoretical understanding of criminal behavior made since 1985 (범죄학 이론의 발전에 영향을 미친 이론들에 대한 고찰: -1985년 이후의 중요한 범죄이론을 중심으로-)

  • Jang, Duck-Hyung
    • Korean Security Journal
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    • no.42
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    • pp.449-468
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    • 2015
  • It is important to identify and discuss what the most vial contributions of criminological theories. In the field of criminology, most significant contributions or advancement have been made on the various issues such as age, the integration of structural and procedural level theories, other theoretical integration debates. However, it is hard to find ant systematic study exploring such a contribution in criminological theories. This study, therefore, has a purpose to discuss three most significant contributions to our theoretical understanding of criminal behavior made since 1985. To accomplish the study purpose, this study choose the followed three theoretical contributions; the emergence of life course theory, the revision of social disorganization theory, and the introduction of social structure and social Learning (SSSL) model. The three theoretical works will be introduced and discussed regarding other theoretical integration trends in the body of this study. The conclusion, contribution of this current study has been discussed in the last conclusion and discussion section.

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