• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.6
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• pp.753-760
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• 2013

The hydrogen embrittlement of metallic materials is an important issue from the viewpoint of structural integrity. In this regard, the estimation of mechanical properties and fracture toughness under hydrogen conditions provides very important data. This study provides an experimental validation of the approach for simulating the small punch of Inconel 617 using finite element damage analysis, as recently proposed by the authors, and applies an inverse method for the determination of the constitutive tensile behavior of materials. The mechanical properties obtained from the inverse method are compared with those obtained from the tensile test and validated. The mechanical properties and fracture toughness are predicted by using the inverse method and finite element damage analysis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.5
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• pp.332-341
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• 1989

Stomach contents and microstructures in otolith of Chaenogobius laevis were analyzed for the determination of age, growth and food. By comparaing structural similarity in a series of growth increments from three samples collected in a two-week interval, daily deposition of growth increments in otolith can be validated. Growth in length as daily basis was well represented by Gompertz curve: $L= 5.73{\cdot}\;e^{15.06}(1-e^{-0.0015t})$ for the fish age of $46\~102$ days. Mean growth rate increased from 0.40 mm/day for the age of $50\~60$ days to 0.85 mm/day for the age of $80\~100$ days. Chasnobius laevis showed a carnivorous feeding behavior and its major food items were polychaetes, amphipods and copepods. Small individuals ($15\~30$ mm SL) preyed heavily on copepods as well as polychaetes. However, the portion of copepods in stomach contents was decreased with increasing fish siEe, and this decrease was compensated by an increased consumption of amphipods.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.9
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• pp.1643-1653
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• 1992

A method, which uses analytical or numerical modal analysis results, e.g. from finite element analysis, to select desirable response measurement and excitation points for an efficient modal testing is introduced. First, points of master degree of freedom(DOP) are determined so as to statistically minimize errors between responses of a full order model and those estimated from the reduced order model. Such master DOF's are selected as the response measurement points. Then a criterion named 'driving point model constant(DPMC)' related to the magnitudes of resonance peaks of the driving point freqency response functions used to select the point of excitation out of the master DOF's. In this work, the method is demonstrated through applications to modal testing on a one dimensional cantilever beam and an aluminum plate and the results are compared with those by another technique. also, the method is applied to a two dimensional structural component of a passenger car.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.22 no.4
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• pp.323-329
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• 2004

Water vapor is an important parameter in monitoring changes in the Earth's climate and it can be used to improve weather forecasting. However, it haven't observed accurately by reasons of structural and economic problem of observation. GPS meteorology technique for precipitable water vapor measurement is currently actively being researched an advanced nation. Main issue of GPS meteorology is an accuracy of PWV measurement related weighted mean temperature and meteorological data. In this study, the korean weighted mean temperature had been recalculated by a linear regression method based on meteorological observations from 6 radiosonde stations for 2003 year. We examined the accuracy of PWV estimates from GPS observations and Radiosonde observations by new korean weighted mean temperature and others.

• Food Science of Animal Resources
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• v.31 no.1
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• pp.27-31
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• 2011

To differentiate between frozen-thawed and fresh broiler breast fillets, different methods such as optical microscopy and measurement of drip loss, pH, torrymeter and K-value were performed. A total of 10 samples of fresh and frozen-thawed breast fillets were stored in a refrigerator ($4^{\circ}C$) for 5 d. Optical microscopy of the frozen-thawed breast fillets found structural changes caused by ice crystals, which may have significantly increased drip loss compared to fresh breast fillet. The pH and K-value could not be distinguished between the two breast fillets during storage. However, the torrymeter values of the fresh and frozen-thawed breast fillets were significantly different (p<0.05). The results indicate that both optical microscopy and torrymeter measurement can be effective methods for differentiating between fresh and frozen-thawed breast fillets. However, optical microscopy may be difficult to implement in the marketplace since it requires much time and effort. Thus, the determination of the torrymeter value is the easiest and most rapid instrumental method among those tested for the differentiation of frozen-thawed chicken breast fillet from fresh one.

• The Korean Journal of Nuclear Medicine
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• v.27 no.1
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• pp.104-111
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• 1993

Trace elements are important components in the biological system, as a structural material and metabolic controller. Neutron activation analysis (NAA) with high neutron flux and high energy resolution Ge (Li) detector coupled to multichannel analyzer (MCA) has been one of the most accurate method for the determination of ultra-trace level components, and is applicable to biological material. In human body, the NAA can be used for quantitation of trace elements in various organs and tissue with endocrinological and metabolic disease and industrial metal poisoning. In this study, Triga Mark III nuclear reactor in Korea Atomic Research Institute was used for quantitation of trace eleement in human lung cancer tissues by neutron activation analysis. In the squamous cell carcinoma tissues, Br, Hg, La, Sb, Sc, Cl, Fe and I content were lower than normal lung tissues, and K, Rb and Se content were higher. In the adenocarcinoma tissues, Fe, Au, La, Sc and Zn content were lower than normal lung tissues, and Rb, Co and Se content were higher. Rb content was higher in the adenocarcinoma tissues than in the squamous cell carcinoma tissues. Fe and Na content were higher in the squamous cell carcinoma tissues than in the adenocarcinoma tissues.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.463-470
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• 2009

Sixteen antioxidative active compounds isolated from the EtOAc layer of MeOH extracts of kochujang, Korean fermented red pepper paste, were structurally elucidated as fumaric acid, methyl succinate, succinic acid furan-2-yl ester methyl ester (gochujangate, a novel compound), 2-hydroxy-3-phenylpropanoic acid, 3,4-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 6,7-dihydroxy-2H-chromen-2-one (esculetin), caffeic acid, cis-p-coumaric acid, trans-p-coumaric acid, daidzin, genistin, apigenin 7-O-$\beta$-D-apiofuranosyl($1{\rightarrow}2$)-$\beta$-D-glucopyranoside, apigenin 7-O-$\beta$-Dglucopyranoside, and quercetin 3-O-$\alpha$-L-rhamnopyranoside by mass spectrometry (MS) and nuclear magnetic resonance (NMR) experiments. These compounds were analyzed for the first time as antioxidants from kochujang.

• Journal of the Korean Wood Science and Technology
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• v.43 no.1
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• pp.36-42
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• 2015

This study examined true modulus of elasticity (MOE) and modulus of rigidity (G) for domestic woods with different slenderness ratios (L/D) using the static bending and stress wave tests. Bending properties of small clear wood specimen of three domestic wood species were determined at 12% moisture content. The results of this study indicated that both MOR and MOE of domestic woods were affected by the slenderness ratio. As the slenderness ratio increased, MOR and MOE increased. G and true MOE of domestic timber beams were obtained at different slenderness ratios by flexure test and stress wave test. The values reported here can be useful if these species woods are used for structural purposes. However, the reported values are only indicative and do not represent the true average of wood species due to the limited number of specimens tested.

• Journal of Distribution Science
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• v.16 no.9
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• pp.25-33
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• 2018

Purpose - The purpose of the study is to analyze the empowerment intermediary role on the relationship between the job distribution and the quality of life. A research on empowerment and social service staffs' job distribution also should be conducted to improve the quality of their lives. Because empowerment, particularly, affects the quality of life, it should be taken a detail discussion for empowerment improvement. Research design, data, and methodology - This paper conducted a questionnaire survey. In total, 722 copies of the structural questionnaire were analyzed. Five parameter subsets were selected to measure the empowerment such as task significance, role performance capability, self-determination, task impact, then, the survey consists of 10 questions. For data analysis, confirmatory factor analysis, discriminant and concentration validity analysis, path coefficient significance, and mediation effectiveness verification were employed. Results - As evidenced from the data analysis, job distribution variables such as job impact, job autonomy, and feedback affect the quality of their lives. Empowerment also affects the quality of their lives. Next, the empowerment functions as meditating role in the relationships with job impact, job autonomy, feedback and the quality of their lives. On the other hand, the empowerment do not function as meditating role in the relationships with social service staffs' function diversity and the quality of their lives. Conclusions - It is necessary to conduct ways for various job performance and outside educational facilities to improve social service staffs' function diversity. The mission, vision, strategic purposes, detailed execution goals need to be set by all their organization members' participation. Empowerment also requires social welfare facilities' drastic delegation on their authority and responsibilities with their active decentralization in the organization.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.10
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• pp.989-998
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• 2020

Electronic commerce is becoming a significant hub for sourcing products/services which helps organizations to connect with potential customers and gain competitive advantages, though little empirical work focuses on small businesses operating in developing countries to date. Increasingly, companies are looking to utilize social media to connect with stakeholders and pursue several benefits. This study aims to investigate the technological, organizational, and environmental (TOE) factors that influence small- and medium-sized enterprises' (SMEs) social media (SM) adoption in developing countries. This study used a closed-ended questionnaire to collect data from randomly-selected respondents (owners, executives, and managers) from SMEs in Pakistan. SMART PLS version 3.2.8 was used for path analysis of 316 responses and for structural equation modeling. The research findings include the direct influence of TOE factors (relative advantage, interactivity, visibility, top management support, and institutional pressure) on SMEs' SM adoption, and in turn SM adoption also has a positive influence on SMEs performance. Moreover, the coefficient of determination of the study showed that 77.7% of the variation in SM adoption occurs because of TOE factors and 29.8% variation in SMEs occurred because of SM adoption. This paper has implications for practitioners and scholars interested in exploring the SM adoption and usage by SMEs.