• 대한조선학회 특별논문집
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• 대한조선학회 2011년도 특별논문집
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• pp.17-20
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• 2011

The International Association of Classification Societies (IACS) had developed the Common Structural Rules (CSR) for bulk carriers as per the needs noted above. ISO and IMO GBS (Goal-Based Standards) are now being developed in this regard. This study has been prepared to verity the strength of forward cargo hold of 82,000 DWT class bulk carriers. A cargo hold/tank 3-D FE model was established to assess the structural adequacy of the primary structural members with the loading conditions. Full breadth model was established for the analysis considering asymmetric nature of structural layout and loading conditions. To summarize this result of structural assessment based on IACS CRS for bulk carrier, it is benefit to design this kind of bulk carriers and to study the strength assessment for the similar type of bulk carriers.

• 경영과학
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• 제21권2호
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• pp.235-252
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• 2004

Recently domestic mobile carriers have been engaged in heated battles for survival as the market is now rapidly approaching its maturity phase. and the launch of 3G service combined with the introduction of mobile number portability is dramatically reshaping the market landscape. The mobile carriers may have to create and maintain their competitive advantage based on their core capabilities and differentiated strategies. which will lead continuous survival and profits of the firm. This paper investigated competitiveness factors among mobile carriers. and analyzed the relationships of firm capabilities. competitive strategies and competitive advantage. We found that core capabilities and competitive strategies affecting competitive advantage are different from each carrier. Finally. we discussed strategic implications for carriers to increase their competitiveness.

• E2M - 전기 전자와 첨단 소재
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• 제9권10호
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• pp.1019-1026
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• 1996

In this study, we may be presented the carrier oscillation properties for the low-voltage varistor fabricated by a new method of three composition seed grain, in order to analyze the behavior of carriers at the its equivalent circuit model. The oscillation phenomena of carriers appeared from current-voltage characteristics under knee voltage is shown by the transient flow of nontrapped carriers group in the trap level of intergranular layer, surface state and/or depletion layer. In particularly, current oscillation phenomena is hardly shown in the high electric field. It is that the injected carriers from both electrodes are directly from the conduction band of forward biased ZnO grain through the intergranular layer into the reverse biased ZnO grain, because the trap level in the electric field above the knee voltage is mostly filled.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2009년도 공동학술대회
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• pp.165-166
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• 2009

본 논문에서는 자동차 운반선의 여러 해상운송계획 중 stowage planning의 최적화를 위한 모형 및 해법을 연구하고자 한다. 이는 향후 연구를 통해 기존에 연구되었던 vessel allocation 및 voyage planning 모형과 함께 자동차 운반선의 통합 해상운송계획 모형을 개발하는 데 활용될 계획이다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 하계학술대회 논문집 B
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• pp.1159-1161
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• 1993

This paper may be presented the carrier oscillation properties for the varistor fabricated by a new method of three-composition seed grain, in order to analyze the behavior of carriers at the its equivalent circuit model. The oscillation phenomena of carriers appeared from current-voltage characteristics under knee voltage is shown by the transient flow of non trapped carriers group in the trap level of intergranular layer, surface state and/or depletion layer. However, Current oscillation phenomena is hardly shown in the high electric field. The injected carriers from both electrodes are directly flowed from the conduction band of forward biased grain through the intergranular layer into the reverse biased grain, because the trap level in the electric field above the knee voltage is mostly filled.

• 환경생물
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• 제27권3호
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• pp.244-251
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• 2009

두 가지 다른 기질의 담체를 이용하여 살조세균 Pseudomonas fluorescens HYK0210-SK09의 포집율과 microcosm에서 Stephanodiscus hantzschii의 살조능을 파악하였다. Active carbon polyvinyl alcohol (ACPA)담체가 cellulose sponge (CS)담체보다 SK09를 높게 포집하였다. 이를 이용한 microcosm에서 ACPA담체가 CS담체보다 S. hantzschii의 살조능이 높았으며 지속적이었다. 특히 ACPA담체에서는 낮은 전기전도도를 나타내어 S. hantzs-chii 분해에 따른 용출된 이온들을 흡수하고 있음을 판단할 수 있었다. 따라서 ACPA담체를 이용한 유해조류 제어는 지속적 제어와 함께 생태계의 교란을 최소화할 것으로 판단된다.

• 한국수소및신에너지학회논문집
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• 제26권6호
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• pp.600-608
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• 2015

As a candidate for cheap oxygen carrier, $CaSO_4$ based oxygen carriers have been developing. However, research on reaction characteristics and side reaction of $CaSO_4$ based oxygen carrier is very limited. There are many possible reactions for main components of syngas from coal. In this study, we prepared three $CaSO_4$ based oxygen carriers ($CaSO_4$-$Fe_2O_3$/bentonite, $CaSO_4$-$K_2CO_3$/bentonite, $CaSO_4$-CaO/bentonite) and performed reduction tests by hydrogen. Cyclic reduction-oxidation tests up to $5^{th}$ cycle are also conducted using hydrogen as fuel. Reduction reactivity of those $CaSO_4$ based oxygen carriers were compared with that of NiO based oxygen carrier (OCN703-1100). Real weight change fractions of $CaSO_4$ based oxygen carriers were higher than theoretical oxyen transfer capacity and reactivity of these particles decreased with the number of cycle increased. To check possible side reaction of $CaSO_4$ based oxygen carriers, $CaSO_4$ decomposition tests were carried out and $SO_2$ was detected even at $700^{\circ}C$. Consequently, we could conclude that $CaSO_4$ based oxygen carriers decompose and release $SO_2$ and this reaction lead reactivity decay of $CaSO_4$ based oxygen carries.

• 유통과학연구
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• 제15권12호
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• pp.53-60
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• 2017

Purpose - This paper analyzes the effect of the handset subsidy and the Mobile Number Portability subscriber subsidy regulation, which are the main regulation adopted in "Law on the Improvement of the Mobile Terminal Distribution System" (Mobile Terminal Distribution Act), on the social surplus, the consumer surplus and profits of telecommunications carriers. We focus our analysis on whether the service charge competition is stimulated enough so that it can compensate for the loss of subsidies. Research design, data, and methodology - We use simple economic model to assess the impact of the handset subsidy and the Mobile Number Portability subscriber subsidy regulation. Unlike the former researches on this topic, we depart from using Hotelling model, and instead use the switching cost model, which uses switching cost as a parameter of market powers of telecommunications carriers. We also study the effect of the two different regulations when they are adopted both independently and concurrently. Results - If the market powers of telecommunications carriers are over certain threshold, contrary to the regulatory agency's assertion, the service charge competition would not be stimulated enough to compensate for the deduction in the subsidies, and thus the consumer surplus is compromised. Number Portability subsidy, especially, undermines the rival's market power and thus reduces the service charge. On the other hand, the regulations will also increase the profits of telecommunications carriers. However, social surplus is maximized when both of the regulations are present because the regulations reduces the frequency of switching handsets inefficiently. Conclusions - In enacting the Mobile Terminal Distribution Act, the telecommunications regulatory agency asserted that the regulation on subsidies will stimulate service charge competition, and in the long run, enhance the consumer surplus. However, contrary to the regulatory agency's assertion, subsidy regulation, especially the regulation on Number Portability subsidy, reduces consumer surplus. On the other hand, the Mobile Terminal Distribution Act can also increase the profits of telecommunications carriers because it decreases competition among the telecommunications carriers. However, the Mobile Terminal Distribution Act can increase the social surplus because it reduces inefficient switching of handsets.

• Asian Pacific Journal of Cancer Prevention
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• 제16권18호
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• pp.8253-8258
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• 2016

Elevated levels of soluble CD30 (sCD30) are linked with various T-cell neoplasms. However, the relationship between sCD30 levels and the development of adult T-cell leukemia (ATL) in human T-cell leukemia virus type 1 (HTLV-1) carriers remains to be clarified. We here investigated whether plasma sCD30 is associated with risk of ATL in a nested case-control study within a cohort of HTLV-1 carriers. We compared sCD30 levels between 11 cases (i.e., HTLV-1 carriers who later progressed to ATL) and 22 age-, sex- and institution-matched control HTLV-1 carriers (i.e., those with no progression). The sCD30 concentration at baseline was significantly higher in cases than in controls (median 65.8, range 27.2-134.5 U/mL vs. median 22.2, range 8.4-63.1 U/mL, P=0.001). In the univariate logistic regression analysis, a higher sCD30 (${\geq}30.2U/mL$) was significantly associated with ATL development (odds ratio 7.88 and the 95% confidence intervals 1.35-45.8, P = 0.02). Among cases, sCD30 concentration tended to increase at the time of diagnosis of aggressive-type ATL, but the concentration was stable in those developing the smoldering-type. This suggests that sCD30 may serve as a predictive marker for the onset of aggressive-type ATL in HTLV-1 carriers.

• 디지털융복합연구
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• 제15권6호
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• pp.189-196
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• 2017

본 연구의 목적은 소셜 미디어 데이터에 대한 감성평가를 활용하여 대형항공사와 저비용항공사 이용 고객의 만족도를 정량적으로 분석하는 것이다. 이를 위해 2008년에서 2016년까지 대형항공사와 저비용항공사가 언급된 총 77,591개의 트윗을 취합하고 항공사 선택 속성별로 분류하였으며, 고객만족도 분석을 위해 3명의 평가자가 감성 평가를 시행하도록 하였다. 분석결과, 최근 7년 간 고객 만족도는 저비용항공사가 대형항공사보다 통계적으로 유의하게(p<0.001) 높은 것으로 나타났으며, 대형, 저비용항공사 모두 고객만족도가 지속적으로 하락하고 있는 것으로 파악되었다. 또한, 항공사 선택 속성 중 예약과 항공기 운항과 관련된 고객만족도가 낮은 것으로 나타났으며, 대형항공사의 경우, 예약과 기내서비스, 마케팅 측면에서 만족도 저하가 최근 심화되고 있는 것으로 판단된다. 본 연구의 결과는 대형항공사와 저비용항공사의 전반적인 고객만족도 향상을 위한 정량적 데이터로 활용 가능할 것으로 기대된다.