• Journal of the Society of Naval Architects of Korea
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• v.30 no.3
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• pp.29-40
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• 1993

The fundamental characteristics of nonlinear free-surface waves generated by a shallowly submerged 3-dimensional hydrofoil are investigated. The fluid is assumed inviscid, incompressible and its motion irrotational. The surface tension on the free-surface is neglected. The hydrofoil is represented by a horseshoe vortex system whose shape is assumed fixed. Also the strengths of vortices are assumed given. The exact problem for the wave potential due to the horseshoe vortex system is formulated by the variational principle based on the classical Hamilton's principle. The localized finite element method is used in the numerical computations. In order to increase the numerical efficiency, an intermediate nonlinear-to-linear transition buffer subdomain for a smooth matching is introduced between the fully nonlinear computation subdomain and the truncated linear infinite subdomain. Also used is the modal analysis to reduce the computation tome drastically. The effect of inflow velocity, submergence depth of the hydrofoil and the shape of circulation distribution on the wave profiles are thoroughly examined. Especially it was possible to investigate the nonlinear influence of the free vortex on the free vortex. The nonlinear free-surface effect on the induced forces on the hydrofoil is also investigated.

• STI Policy Review
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• v.5 no.2
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• pp.65-95
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• 2014

The recent decades have seen a growing rate of international cooperation in science, technology, and innovation (STI) including in the field of green technologies. However, current approaches to national systems of innovation (NSI) have not kept up with this development. International aspects are rather treated as external conditions within which policymakers operate and respond but not influence. This paper tackles this problem by applying a refined NSI concept that includes an international dimension and complements past frameworks by focusing on those Korean government policies, actors, and activities relevant for the internationalization of STI. Austria and Korea have both formulated differing strategies to acquire international leading positions in the field of innovation and the development of green technologies. In the first step, the paper assesses Korea's international activities within the field of green technologies that transcend national boundaries and establish international connections. The government has still a strong influence on selecting technology areas for strategic funding but our findings show that international STI actors have difficulties in identifying the appropriate point of contact to initiate cooperation or apply for related funding. Second, an external perspective on Korea's international collaborations in the field of green technologies is offered. Austria has tentatively identified the East Asian country as a second-priority cooperation partner for its future STI internationalization activities. Interviews with Austrian stakeholders in the field of green technologies indicate a high interest in cooperation with Korea that is facilitated by a similar business culture based on personal networks. Moreover, researchers and policymakers referred to a shared need of small countries for intelligent decision-making processes regarding potential cooperation partners abroad. However, in order to enhance awareness, visibility and demand for Korean STI cooperation in European countries, more long-term funding programs featuring a more permanent point of contact should be introduced.

• Nuclear Engineering and Technology
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• v.47 no.7
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• pp.791-803
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• 2015

The effective cross sections (XSs) in the direct whole core calculation code nTRACER are evaluated by the equivalence theory-based resonance-integral-table method using the WIMS-based library as an alternative to the subgroup method. The background XSs, as well as the Dancoff correction factors, were evaluated by the enhanced neutron-current method. A method, with pointwise microscopic XSs on a union-lethargy grid, was used for the generation of resonance-interference factors (RIFs) for mixed resonant absorbers. This method was modified by the intermediate-resonance approximation by replacing the potential XSs for the non-absorbing moderator nuclides with the background XSs and neglecting the resonance-elastic scattering. The resonance-escape probability was implemented to incorporate the energy self-shielding effect in the spectrum. The XSs were improved using the proposed method as compared to the narrow resonance infinite massbased method. The RIFs were improved by 1% in $^{235}U$, 7% in $^{239}Pu$, and >2% in $^{240}Pu$. To account for thermal feedback, a new feature was incorporated with the interpolation of pre-generated RIFs at the multigroup level and the results compared with the conventional resonance-interference model. This method provided adequate results in terms of XSs and k-eff. The results were verified first by the comparison of RIFs with the exact RIFs, and then comparing the XSs with the McCARD calculations for the homogeneous configurations, with burned fuel containing a mixture of resonant nuclides at different burnups and temperatures. The RIFs and XSs for the mixture showed good agreement, which verified the accuracy of the RIF evaluation using the proposed method. The method was then verified by comparing the XSs for the virtual environment for reactor applicationbenchmark pin-cell problem, as well as the heterogeneous pin cell containing burned fuel with McCARD. The method works well for homogeneous, as well as heterogeneous configurations.

• Plant Resources
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• v.7 no.1
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• pp.29-35
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• 2004

Root chicory (Cichorium intybus L. var. sativus) is potential alternative medicinal and sugar crop which accumulates a high amount of linear polyfructan, inulin in its roots. A problem in root production is that over-wintered stock plants often flower. Once the plant becomes reproductive, stem elongation and root growth slows and floral buds arise from every node, rendering the plants useless for propagation. The objectives of this research was to examine the effectiveness of manipulating environmental factors containing photoperiod, temperature and number of leaf states. The experiment was performed in growth chamber to create two photoperiods (8 h, and 16 h) with three temperature regimes (5$^{\circ}C$/3$^{\circ}C$, 1$0^{\circ}C$/8$^{\circ}C$ and 15$^{\circ}C$/13$^{\circ}C$ day/night temperature) for a total of six treatments on three type of true-leaf stage of plant. Data of bolting rate, shoot and root length, shoot and fresh weight was invetigated in each treatments. This is the first report on changes in bolting rate and shoots and roots production during a whole growing season and differences in the effect of cold and photoperiod treatment depending on the true-leaf stage of plant.

• Advances in nano research
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• v.5 no.4
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• pp.281-301
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• 2017

In this disquisition, an exact solution method is developed for analyzing the vibration characteristics of magneto-electro-elastic functionally graded (MEE-FG) beams by considering porosity distribution and various boundary conditions via a four-variable shear deformation refined beam theory for the first time. Magneto-electroelastic properties of porous FG beam are supposed to vary through the thickness direction and are modeled via modified power-law rule which is formulated using the concept of even and uneven porosity distributions. Porosities possibly occurring inside functionally graded materials (FGMs) during fabrication because of technical problem that lead to creation micro-voids in FG materials. So, it is necessary to consider the effect of porosities on the vibration behavior of MEE-FG beam in the present study. The governing differential equations and related boundary conditions of porous MEE-FG beam subjected to physical field are derived by Hamilton's principle based on a four-variable tangential-exponential refined theory which avoids the use of shear correction factor. An analytical solution procedure is used to achieve the natural frequencies of porous-FG beam supposed to magneto-electrical field which satisfies various boundary conditions. A parametric study is led to carry out the effects of material graduation exponent, porosity parameter, external magnetic potential, external electric voltage, slenderness ratio and various boundary conditions on dimensionless frequencies of porous MEE-FG beam. It is concluded that these parameters play noticeable roles on the vibration behavior of MEE-FG beam with porosities. Presented numerical results can be applied as benchmarks for future design of MEE-FG structures with porosity phases.

• International Area Studies Review
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• v.15 no.2
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• pp.25-47
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• 2011

The paper will investigate the chances of progress in the peace process in Middle East. Robert Hazo's 1993 article mainly argued the Palestinians and Syrian problems. He saw that these two problems are one of the key issue that current Middle East problem which involves Israel. The key tenants of his argument will be dissected to assess whether this view holds true in the light of developments in the Middle East in the intervening years. The Arab-Israeli struggle remains one of the most intractable in history. In 1993 Robert Hazo concluded that 'the conflict is a terminal struggle'. This paper investigates his analysis in light of progress or lack of in the intervening period and against the contemporary strategic environment. It uses information presented in academic, government, newspaper and world wide web articles to conclude that Hazo's assessment remains valid. While the various talks since 1993 combined with the potential benefits the United States, Israel and Syria could gain from a settlement proffer hope, the issue of 'right of return, borders and Jerusalem are unlikely to be bridged in the near future.

• Textile Coloration and Finishing
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• v.30 no.4
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• pp.313-320
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• 2018

As carbon fiber reinforced composites(CFRP) are widely used in aerospace, automobile, marine, and sports goods applications, they have been studied extensively by various researchers. However, CFRP have been pointed out because of machining problems such as delamination and burr phenomenons. Especially, hole machining process, drilling, has non-smooth features on inlet and outlet surfaces of drilled hole. This kind of machining problem can be controlled to some extent by using high modulus pitch-CF, which has considerable effects on fracture behavior of composite compared with only PAN CF composite. Therefore, PAN and pitch hybridized CF composites were prepared having high strength and modulus. The results demonstrate that the hybrid CFRP specimens with pitch CF offer the good potential to enhance modulus as well as strength properties. Dynamic mechanical, flexural, and impact properties were measured and analyzed. Morphological surface of the composites were also observed by IFS-28, canon after hole machining.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.29 no.1
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• pp.187-194
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• 2019

Ever since the world's largest Bitcoin Echange, (Mt. Gox), was closed in March 2014 due to the series of hacking, still many other Exchages incl. recent Coinale in Korea have been attacked. Those hacking attempts never stopped and have caused significant threats to the overall industry of Crypto Currency and resulted in the loss of individual investors' asset. The DEX (Decentralized Exchange) has been proposed as a solution to fix the security problem at the Exchange, but still it is far away to resolve all issues. Therefore, this paper firstly analyzes security threats against existing Crypto Currency Exchanges and secondly derives security requirements for them. To do that it proposes a secure and distributed Crypto Currency Transaction Model through Personal Security devices as a solution. The paper also proves this new attempt by demonstrating its unique modelling; ultimately by adopting this modeling into Crypto Exchange is to avoid potential security threats.

• Nutrition Research and Practice
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• v.13 no.1
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• pp.23-31
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• 2019

BACKGROUND/OBJECTIVES: A large number of studies on anemia have focused mostly on pregnant women or children. The vegetarian population, which is another potential risk group for anemia, remains largely unexplored. Therefore, this cross-sectional study examined the associations of the sociodemographic, lifestyle, nutritional, and psychological factors with the anemia status among female adult vegetarians. SUBJECTS/METHODS: A total of 177 female vegetarians were recruited from a Buddhist and Hindu organization in Selangor, Malaysia. The participants completed a self-administered questionnaire, which analyzed their sociodemographic characteristics, physical activity level, sleep quality, depression, anxiety, and stress. The body weight, height, waist circumference, and body fat percentage of the participants were also measured. A 3-day dietary recall was conducted to assess their dietary intake. Blood samples (3 ml) were withdrawn by a nurse from each participant to determine the hemoglobin (Hb) level. RESULTS: The findings revealed 28.2% of the participants to be anemic. The age group (AOR = 2.46, 95% CI = 1.19-5.05), marital status (AOR = 2.69, 95% CI = 1.27-5.71), and percentage of energy from protein (AOR = 5.52, 95% CI = 1.41-21.65) were the significant predictors of anemia. CONCLUSIONS: Anemia is a public health problem among female vegetarians in this study. Health promotion programs that target female adult vegetarians should be conducted to manage and prevent anemia, particularly among those who are married, aged 50 and below, and with an inadequate protein intake.

• Journal of Digital Convergence
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• v.17 no.9
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• pp.71-78
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• 2019

This study aims to identify good borrowers within the context of P2P lending. P2P lending is a growing platform that allows individuals to lend and borrow money from each other. Inherent in any loans is credit risk of borrowers and needs to be considered before any lending. Specifically in the context of P2P lending, traditional models fall short and thus this study aimed to rectify this as well as explore the problem of class imbalances seen within credit risk data sets. This study implemented an over-sampling technique known as Synthetic Minority Over-sampling Technique (SMOTE). To test our approach, we implemented five benchmarking classifiers such as support vector machines, logistic regression, k-nearest neighbor, random forest, and deep neural network. The data sample used was retrieved from the publicly available LendingClub dataset. The proposed SMOTE revealed significantly improved results in comparison with the benchmarking classifiers. These results should help actors engaged within P2P lending to make better informed decisions when selecting potential borrowers eliminating the higher risks present in P2P lending.