• Geomechanics and Engineering
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• 제21권4호
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• pp.349-356
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• 2020

Rock brittleness, which is closely related to the failure modes, plays a significant role in the design and construction of many rock engineering applications. However, the brittle-ductile failure transition is mostly ignored by the current statistical damage constitutive model, which may misestimate the failure strength and failure behaviours of intact rock. In this study, a new statistical damage model considering rock brittleness is proposed for brittle to ductile behaviour of rocks using brittleness index (BI). Firstly, the statistical constitutive damage model is reviewed and a new statistical damage model considering failure mode transition is developed by introducing rock brittleness parameter-BI. Then the corresponding damage distribution parameters, shape parameter m and scale parameter F₀, are expressed in terms of BI. The shape parameter m has a positive relationship with BI while the scale parameter F₀ depends on both BI and ε_e. Finally, the robustness and correctness of the proposed damage model is validated using a set of experimental data with various confining pressure.

• 한국항만경제학회지
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• 제27권4호
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• pp.13-35
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• 2011

한국과 같이 무역의존도가 높은 국가에서 항만은 국제무역증진, 해운산업의 발달 및 연관산업을 직간접으로 발전시킨다는 점에서 경제적 중요성이 크다고 할 수 있다. 또한 항만은 상품의 수출입기능을 수행하는 육 해상수송의 연결지로서 뿐만 아니라 생산수단으로서 더욱 중요한 역할을 수행하고 있다. 항만 서비스 요인들의 효율성을 달성하기 위해서는 항만 물류정보화에 대한 시스템 구축이 선행되어야 한다. 또한 항만에서의 정보기술에 대한 사용자의 수용행태를 이해하고 보다 효율적인 항만물류 서비스 목적을 달성하기 위해 지속적인 항만물류 서비스 시스템을 개선해야 할 것이다. 본 연구에서는 항만물류서비스의 정보기술 서비스의 수용의도에 영향을 미치는 요인들을 기술수용모델을 기반으로 항만서비스 사용기업들의 특성을 반영한 연구모형을 개발하였다. 이와 같은 개발된 연구모형에 따라 항만물류 서비스의 기술수용모델의 요인들을 개발하여 항만서비스의 기술수용모델의 적용에 따른 효율성을 찾고자 한다. 결론적으로 항만에서 정보기술을 도입하여 항만 이용 당사자에게 제공함으로써, 항만제품 서비스 품질에 만족할 수 있고, 항만서비스에 정보기술을 도입하면 사용행동의도가 높아진다는 것이다. 그리고 사용행동의도가 실제적으로 항만 서비스 품질을 사용하는데 긍정적 효과가 있다. 따라서 항만 관계 시설에 정보기술을 도입하면, 항만 이용자에게는 업무 신속성과 비용절감, 인적감소, 항만 환경보호 등 전반적으로 직간접적인 항만 생산성 향상에 기여하게 될 것이다. 따라서 항만 정보기술의 지속적인 개발과 도입을 함으로써 글로벌 경쟁력을 발생할 것이다.

• 대한토목학회논문집
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• 제26권4B호
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• pp.433-437
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• 2006

최근, 활성 슬러지 공법에 대한 수학적 모델링은 폐수처리장의 설계와 운영에 있어서 매우 중요한 인자로 인식되고 있다. 그럼에도 불구하고, BNR 공정에서 미생물의 성장 및 호흡과 관련한 내 외부 기질의 이용 경로에 관한 정보는 여전히 부족한 실정이다. 본 논문에서는 ASM No.3와 비교되는 새로운 개념의 활성슬러지 모델을 제시하고자 한다. 미생물의 단계별 성장이론에 근거한 이 모텔의 구조는 호기성 저장, 내부저장물질(ISCs; Intercellular Storage Compounds)과 외부기질 활용에 따른 미생물의 성장, 내생호흡과 내부저장물질을 이용한 호기성 호흡 등 5 단계로 구성되어 있다. 단계적 성장모델에 기초한 예측결과는 산소이용율(OUR)과 TCOD에 의한 실험결과에 있어 ASM No.3의 결과보다 더욱 일치함을 나타냈다.

• 한국치위생학회지
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• 제15권5호
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• pp.823-829
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• 2015

Objectives: The objective of the study was to investigate the related factors of non-utilization of dental care among Korean adults. Methods: Korean National Health and Nutrition Survey 2012 was carried out in South Korea. A total of 5,589 adults were interviewed and examined. A multinominal logistic regression model was used to estimate the odds ratio with 95% confidence intervals for the non-utilization of dental care. Results: The non-utilization of dental care was shown to have a badly perceived oral health status, less toothbrushing before sleeping(OR=1.18: 95% CI=1.00-1.39), periodontitis symptoms (OR=1.82: 95% CI=1.50-2.22), toothache experience (OR=2.03: 95% CI=1.75-2.34), TMJ symptom experience (OR=3.31: 95% CI=2.74-3.99), speaking problem (OR=1.87: 95% CI=1.75-2.34) and a partial dentures needs (OR=2.49: 95% CI=1.93-3.19). Conclusions: The non-utilization of dental care tended to have badly perceived oral health status, less toothbrushing before sleeping, periodontitis, toothache experience, TMJ symptom experience, speaking problem, and partial dentures needs.

• Journal of Preventive Medicine and Public Health
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• 제21권2호
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• pp.404-418
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• 1988

The household survey was performed in a urban slum and a rural Chonnam areas to measure the level of illness and medical care utilization and to find the determinants of physician utilization. The data revealed that age-adjusted prevalence rates of acute and chronic diseases were much the same in both areas ranged between 10.0 to 11.3%. But medical care utilization was more frequent in urban slum than in rural area. The facility of the first medical contact was also different. Some personal and disease related variables including disease severity and activity restricted day were significantly, but somewhat differently by area, associated with physician utilization pattern. When applying Anderson model, the medical need factors explained 42.2 and 40.4% of physician utilization in urban slum and in rural areas respectively, while the enabling factors explained 18.0 and 12.2% and the predisposing facotrs explained 17.1 and 8.9% correspondingly.

• 융합경영연구
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• 제11권6호
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• pp.43-55
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• 2023

Purpose: The purpose of this study was to identify the relationship between smart factory utilization and continued use intention between UTAUT, dynamic capabilities of smart factory construction companies and present the company's strategic direction. Research design, data, and methodology: In this study, a structured research model was derived to confirm the relationship between UTAUT, dynamic capabilities, smart factory utilization and continued use intention and the difference according to Technology perception. For analysis a total of 223 valid questionnaires from e-commerce users were used. Confirmatory factor analysis, correlation analysis, and structural equations were conducted to verify. Results: Both UTAUT, dynamic capabilities had a significant effect on smart factory utilization as well as continued use intention. It was found that the relationship between UTAUT, dynamic capabilities, smart factory utilization, and continued use intention. differed depending on the technology perception. Conclusions: Organizational members utilize the smart factory in anticipation of effects such as work performance and various improvements. Smart factory data will be used continuously when it is useful for business processes and operations. It is necessary to establish strategies and provide training to improve the technical level and capabilities of organizational members. Through this, a strategy is needed that can be continuously used by utilizing the information obtained through smart factory to improve work efficiency, productivity and efficiency increase is needed

• International Journal of Knowledge Content Development & Technology
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• 제13권3호
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• pp.75-93
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• 2023

A cross sectional survey method was used to determine the utilization of e-resources and their influence on the reading culture of 119 undergraduate students registered with the JD Amin library of Federal University Dutse. The data collected was analysed using both descriptive (frequency counts and means) and inferential statistics (regression analysis). The research found that databases (mean=4.00) and e-journal (mean=4.00) are available to the undergraduate students. It further found that e-resources are often utilized by the undergraduate student, with social media (mean=4.00), databases (mean=4.00) and e-journal (mean=4.00). the most commonly used e-resources. It was also found that erratic power supply (mean=3.91) and inability to seek, obtain and evaluate information (mean=3.67) are the prominent factors hindering the utilization of e-resources. The regression analysis rejected the null hypotheses of the study where it shows that the level of utilization of e-resources have positive statistical correlation (r=0.772) with the reading culture of undergraduate students. The study proposed a conceptual model for the sustainable reading culture of students by libraries providing of e-resources. The general conclusion of the research is that e-resources are necessary tools and are moderately available and adequately utilized for influencing reading culture. The study recommended that Internet facilities should be made available to undergraduate students to facilitate more utilization of e-resources.

• 한국식품영양과학회지
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• 제28권1호
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• pp.178-190
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• 1999

This study was conducted to develop a simulation model for the growth dynamics of pigs and to describe quantitatively protein deposition depending on the amino acid composition of feed protein. In the model it is assumed that the essential processes that determine the utilization of feed protein in the whole body are protein synthesis, breakdown of protein, and oxidation of amino acid. Besides, it is also assumed that occurrence of protein deposition depends on genetic potential and amino acid composition of feed protein. The genetic potential for the protein deposition is the maximum capacity of protein synthesis, being dependent on the protein mass of the whole body. To describe the effect of amino acid composition of feed on the protein deposition, a factor, which consist of ten amino acid functions and lie between 0 and 1, is introduced. Accordingly a model was developed, which is described with 15 flux equations and 11 differential equations and is composed of two compartments. The model describes non linear structure of the protein utilization system of an organism, which is in non steady state. The objective function for the simulation was protein deposition(g/day) cal culated according to the empirical model, PAF(product of amino acid functions) of Menke. The mean of relative difference between the simulated protein deposition and PAF calculated values, lied in a range of 11.8%. The simulated protein synthesis and breakdown rates(g/day) in the whole body showed a parallel behavior in the course of growth.

• Management Science and Financial Engineering
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• 제11권2호
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• pp.61-84
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• 2005

This paper considers a special case of the two-dimensional bin-packing problem for identical items. The objective of this work is to maximize the space utilization. The main contribution of the paper is to suggest a new heuristic algorithm keeping in view the existing complexity of racking system for the footwear boxes in the compartments of different sizes for a warehouse. The results show that a significant improvement can be obtained. An economic choice of compartments is also estimated using the criteria for maximizing space utilization. A non-linear mathematical model was presented based on the constraints of racking dynamics.

• Journal of Microbiology and Biotechnology
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• 제24권11호
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• pp.1551-1558
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• 2014

The esterase gene Est8 from the thermophilic bacterium Bacillus sp. K91 was cloned and expressed in Escherichia coli. The monomeric enzyme exhibited a theoretical molecular mass of 24.5 kDa and an optimal activity around $50^{\circ}C$ at pH 9.0. A model of Est8 was constructed using a hypothetical YxiM precursor structure (2O14_A) from Bacillus subtilis as template. The structure showed an ${\alpha}/{\beta}$-hydrolase fold and indicated the presence of a typical catalytic triad consisting of Ser-11, Asp-182, and His-185, which were investigated by site-directed replacements coupled with kinetic characterization. Asp-182 and His-185 residues were more critical than the Ser-11 residue in the catalytic activity of Est8. A comparison of the amino acid sequence showed that Est8 could be grouped into the GDSL family and further classified as an SGNH hydrolase. Est8 is a new member of the SGNH hydrolase subfamily and may employ a different catalytic mechanism.