• Journal of the Korean Graphic Arts Communication Society
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• v.22 no.2
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• pp.37-54
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• 2004

IPNs have interpenetrating motion and phase separation behavior of independent polymers, respectively, and also these are affected by the physical interaction of polymer components. First of all, 2- and 3-component IPNs based on PU are prepared by combination with two or three components of PU, PMMA, PS and epoxy resin. And then the entire physical properties concerning morphological and mechanical behaviors of these IPNs are measured by employing FT-IR, SEM, Rheovibron, and DSC, etc. Compared with pure component, Tg's of IPN are shifted to higher temperature in all IPN kinds, and these are considered in attribution to internal movement of glass transition temperature or partial phenomenon of interpenetration. Rheovibron measurement results in a broader distribution with peaks of tan${\delta}$ or E", and this morphologically represents a medium degree of partially mixed IPNs in confirmation of SEM photographs.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.07a
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• pp.284-286
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• 2011

LDPC(low density parity check) 부호는 낮은 복잡성과 Shannon의 한계에 근접하는 오류 정정 능력을 보이기 때문에 turbo 부호와 함께 많은 응용분야에 적용되고 있다. 본 논문에서는 분산 동영상 부호화(distributed video coding: DVC) 시스템을 위한 부호율 적응적인(rate adaptive) LDPC 부호를 설계하기 위하여 패리티 점검 노드를 병합하는 방법을 제안한다. ACE(approximation cycles EMD) 알고리즘을 기반으로 효율적인 LDPC 부호를 설계하고 부호율 적응적인 특성을 갖기 위해 일정한 범위를 지정하고 지정된 범위에 따라 패리티 점검 노드를 병합한다. 그리고 ACE 알고리즘의 계수와 degree distribution을 변화시키면서 성능을 해석한다.

• The Journal of Asian Finance, Economics and Business
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• v.2 no.3
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• pp.41-46
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• 2015

Energy saving in the transport sector in the framework of the annual growth of energy consumption, the degree of negative impact on the environment and the amount of harmful emissions are becoming increasingly important. The article considers the world tendencies of energy consumption in transportation sector and emphasizes its dependency from oil. Also article describes the dynamics of energy use and CO₂ emissions from transport of city Almaty. In conclusion authors identify a number of problems in the transport sector, which hinder the implementation of energy efficiency measures and measures to reduce CO₂ emissions.

• Journal of the Korean Mathematical Society
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• v.47 no.2
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• pp.385-407
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• 2010

To study the relationship between the levels of chemical pollutants and the number of daily total hospital admissions for respiratory diseases and to find the effect of temperature/relative humidity on the admission number, Wong et al. [17] introduced the varying-coefficient single-index model (VCSIM). As pointed out, it is a popular multivariate nonparametric fitting technique. However, the tests of the model have not been very well developed. In this paper, based on the estimators obtained by the local linear technique, the average method and the one-step back-fitting technique in the VCSIM, the generalized likelihood ratio (GLR) tests for varying-coefficient parts on the VCSIM are established. Under the null hypotheses the new proposed GLR tests follow the $\chi^2$-distribution asymptotically with scale constant and degree of freedom independent of the nuisance parameters, known as Wilks phenomenon. Simulations are conducted to evaluate the test procedure empirically. A real example is used to illustrate the performance of the testing approach.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.11a
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• pp.81-84
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• 1998

New diagnostic techniques have been tried on the applications of chemical, physical and micro-structural methods because there was a limit to diagnose degradation in Korean Underground Residential Distribution (URD) power cables with the conventional electrical methods. In this study, non-electrical properties were carried out as such. Characterization of interface layer was analyzed by X-ray, characterization of insulator by water tree, degree of crosslinking, shrinkage as well as ${\mu}$ -FTIR, characterization of semiconductive layer by volume resistivity. Electrical properties were also performed by leakage current.

• Journal of Chest Surgery
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• v.35 no.9
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• pp.701-703
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• 2002

The result of compensatory sweating after surgical treatment for essential hyperhidrosis had problems in objectivity and validity because it mainly depended on the subjective symptoms of patients. Therefore, we tried to evaluate more precisely and objectively, the distribution and degree of compensatory sweating by D.I.T.I.(Digital Infrared Thermographic Imaging) with subjective symptoms.

• Journal of Plant Biology
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• v.28 no.3
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• pp.191-198
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• 1985

The processes of vegetation development and interspecific association were studied as a part of a successional study in the sand bars at the Nadgdong River estuary in Korea. The major pioneer plant species in the sand bars were Salsola komarovi, Carex pumila and Cynodon dactylon. In embryonic sand bars, Namusitdeung and Galmaegideung, the processes of vegetation development after colonization by pioneer species were closely interdependent with the development of the sand dune. The vegetation types of embryonic sand bars were divided into two groups: sand dune plants, and annual and perennial forbs. Those of old sand bars, Baeghapdeung and Ogryudeung, were also divided into tow groups: sand dune plants, and salt marsh plants. The results of interspecific association coincided well with the actual distribution of plant communities in the sand bars. The degree of vegetation development in each sand bar agreed with the order of successional stage observed in this study area.

• The Journal of Fisheries Business Administration
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• v.13 no.1
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• pp.47-61
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• 1982

This paper first makes a survey of fishing household economy which possess fishing boats under 10 gross Tons by a questionnaire, and makes a comparative study of major indicators of fishing household economy between Korea and Japan, and finally suggests some policies for the fisheries management. Major indicators are the status of fishery household members, number of fishing boats which possess, fisheries incomes, fishing household incomes, side business incomes of fishing household, disposal incomes, living expenses, sufficient degree of living cost, average propensity to consumption and so on. Some policies for improvement in fishing household incomes are suggested in the paper as follows: ⑴ Form a policy similar to a project aiming for increasing the income of fishermen so that the side business income will also increase. ⑵ The point of view in tracing origin of low productivity. ⑶ It has drawn up a plan to encourage saving after analyzing the cause of high propensity to consumption. ⑷ The paper is aimed to collect basic statistical materials for fisheries administration.

• Transactions of Materials Processing
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• v.21 no.2
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• pp.101-106
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• 2012

Generally, rapid cure reaction of LED encapsulation silicone resin causes serious defects in cured resin products such as warpage, residual bubbles, and reduced wettablility. In order to prevent residual bubbles in silicone resin, the step cure process was examined in the present paper. Three kinds of step cure processes were applied, and bubble-free phenomenon was observed. Most of the bubbles were removed under $70^{\circ}C$, the minimum temperature for activating cure reaction. In addition, degree of cure(DOC) and temperature distribution were predicted by using FEM analysis of heat transfer. It was concluded that maintaining cure temperature which provide a DOC under 0.5~0.6 effectively reduces residual bubbles.

• Progress in Superconductivity and Cryogenics
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• v.3 no.2
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• pp.77-83
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• 2001

The thermal characteristics of solid nitrogen are investigated by experiment and analysis for the purpose of evaluating its feasibility as a cooling medium for HTS (high T$_{c}$ superconductor) magnets. A cryostat to refrigerate a liquid-nitrogen container well below its freezing temperature with a 2-stage GM cryocooler is designed and constructed. The spatial distribution of temperature is measure as a function of time during the freezing and melting processes. from which the thermal diffusivity of solid nitrogen can be approximately calculated. the freezing process is formulated and solved by the integral method with an assumption of phase equilibrium at the solid-liquid interface and experimental observation. It may be concluded that the thermal diffusion in solid phase is much slower than in liquid and the degree of super-saturation is quite severe in the solidification of nitrogen.n.