• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.10
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• pp.82-90
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• 2013

An Optical Network-on-Chip(ONoC) based on silicon photonics is one of promising technology for next generation exascale computing architectures. Recent active researches on ONoC focus on improving bandwidth further and avoiding path collisions by using wavelength division multiplexing (WDM). However, the number of wavelengths used for the WDM increases linearly as the number of Processing Element (PE) increases in existing ONoCs which adopt centralized routing architecture. The problem will also arises growing cost of optical devices such as light switches and light sources and limits the scalability of ONoC due to the sinal loss caused by interference of distinct light sources. In this paper, we proposes a distributed routing architecture for ONoC which is based on 2D-mesh structure using WDM technique and present a method that minimize the required number of wavelengths exploiting the connectivity of communication. In comparison with existing centralized routing architectures, results show reduction by 56% of the number of wavelengths and 21% of the number of optical switches in $8{\times}8$ networks.

• Journal of the Korean Chemical Society
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• v.43 no.1
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• pp.28-42
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• 1999

Polysilanes with sterically bulky substituents, -[2-( $R^1R^2$-phenyl)propyl]Si[$R^3$]-, such as poly(2-phenylpropyl)(n-hexyl)silane [$R^1=R^2$=H, $R^3$=n-hexyl] were prepared by Wurtz-type coupling reactions with Na using a sonochemical method. The high-intensity ultrasound provided the formation of high quality Na dispersion in toluene and its active surface which was important for the synthesis of polysilanes in Wurtz-type coupling reaction was freshly and continuously regenerated during the process. The polysilanes products were mixtures of high molecular weight polymers with $\={M}_W$ of ∼$10^6$ and low molecular weight polymers with $\={M}_W$ of ∼$10^3$. It was found that the formation of high molecular weight polymerr was greatly influenced by the substituents $R^3$, directly attached to Si. On the contrary, changes on substituents ($R^1, R^2$) gave no influences at all. Overall yields for polysilanes were 75-99% in general but high molecular weight polysilanes were obtained as a major product when substituent $R^3$ is n-hexyl group and low molecular weight polysilanes were obtained as a major product when substituent $R^3$ is cyclohexyl and 2-phenylethyl groups. Effects of reaction conditions to polysilane yields were investigated.

• Journal of the Korean Chemical Society
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• v.42 no.1
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• pp.122-134
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• 1998

In this review, we describe the electrochemical properties of spinel-type lithium manganese oxides $(Li_xMn_2O_4)$ and their failure modes encountered in 4 V lithium rechargable cells. The long-term cyclability (reversibility) of spinel electrodes is determined partly by the purity, size and distribution of spinel particles, and also by the microstructure of electrode plates. A proper selection of electrolytes is another important task in cyclability enhancements. In the spinel preparation, impurity formation and cation mixing should be minimized. The carbon content in composite cathodes should also be minimized to the extent where the cell polarization does not bring about adverse effects on cell performances. The binder content should be optimized on the basis of dispersion of component materials and mechanical strength of the plates. Cathodic capacity losses arising from solvent oxidation and spinel dissolution can be mitigated by using electrolytes composed of carbonates and/or fluorine-containing lithium salts. The carbon additives may be selected after a trade-off between the cell polarization in composite cathodes and the solvent oxidation on carbon surface.

• Journal of fish pathology
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• v.1 no.1
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• pp.51-57
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• 1988

Pleistophora disease is well known as microsporidiosis at eel cultural farms in Korea in recent years. Major objects of this study were to undertake the induction of Pleistophora infection experimentally and to carry out histopathological investigation from December 1984 to June 1986. Experimental infection of Pleistophora spores into young eels was carried out by oral and immersed administration. Both methods induced the same symptom successfully as that in naturally occurring diseased fish. Remarkable whitish lesions developed mainly on the body surface around the abdomen when orally administrated. On the other hand, they were scattered over the whole body when administrated through immersion. Histopathological investigation revealed that some cysts in the muscle were observed 21 days after administration. Spores were developed within the cyst. Each sporont has undergone several nuclear divisions to form a pair of multinucleate cells (Sporoblasts) enclosed within a common coat (Pansporoblast). All stages were surrounded by cyst. The cysts were destroyed and mature spores were scattered in the muscle.

• Journal of Gifted/Talented Education
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• v.21 no.3
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• pp.773-796
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• 2011

This study examined the thinking styles of scientifically gifted students on the basis of Sternberg's theory of mental self-government, and the relationship between thinking styles and self-regulated learning ability of the students and their scientific inquiry ability by the different types of thinking styles. 110 middle school students who belonging to the university science-gifted education center participated in this study. 13 thinking styles were postulated that fall along 5 dimensions which are functions, forms, levels, scopes and leanings of the mental self-government. Scientifically gifted students responded to the Thinking Style Inventory (TSI) that standardized Korean version, Self-regulated Ability Inventory and Test of Science Inquiry Skills Inventory (TSIS). The results indicated that scientifically gifted students prefer legislative, liberal, external, hierarchical and judical thinking styles, rather than conservative style. This result also showed that subscales of thinking styles were significantly correlated with self-regulated learning ability and scientific inquiry ability. The legislative style, hierarchical style, local style and liberal style were significant predictors of self-regulation learning ability. The legislative style was significant predictor, whereas oligarchic style was negative predictor of scientific inquiry ability. The results of k-means clustering analysis and MANOVA showed that the self-regulated learning ability and scientific inquiry ability were significantly correlated with the pattern and level of thinking style.

• Journal of Internet Computing and Services
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• v.9 no.5
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• pp.59-72
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• 2008

Computing systems in the modern era are expanding rapidly to include mobile-based businesses that make us of the various convergence distributed business process. This has lead to growing interest in the field of mobile embedded software development methodology, which has in turn lead to the proliferation of the embedded mobility. The use of CBD (Component Based Development) provides reusability, maintainability and portability, all of which are very important and focus issues to the business process. It also comes with the inherent productivity, quality and reliability of CBD. To make efficient use of CBD, though, clarified interface definitions for component integration are necessary. These definitions should be made up of collaborative hierarchical and horizontal architecture layers. Successful definitions should apply an effective framework made up of the architecture and process. In this paper, we describe an interface specification for small grained mobile embedded components(MEC) for the mobile embedded domain to meet maximum user requirements. We build and deploy the reconfigurable design patterns and components (in business domain categories) to make a component hierarchy and business logics for mobile embedded software. Proposed components specification plays a major role in development of the software for handling inconsistency in existing specification. It also includes plenty of specification information, using semantics and modeling based mechanisms to support business processes. We propose a development model of mobile embedded software using CBD for very complex and dynamic mobile business. We can apply it in a plug and play manner to develop the software. We verify that our framework supports very good productivity, quality and maintainability to meet the user's requirements in mobile business.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.143-143
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• 2003

최근 생활수준 및 생활환경의 향상에 힘입어 청결 및 쾌적을 추구하는 것이 사회적 현상으로 나타나고 있다. 요즘처럼 현대화된 시대에 '왜 항균제가 필요한 것일까' 라는 자연스러운 의문이 발생하게 되지만 현실은 항균제를 이용한 다양한 항균제품, 항균가전제품, 항균가공 내ㆍ건자재 및 항상 신선한 선도를 유지할 수 있는 제품 등이 호황을 누리고 있는 것이 현실이며 그 시장 규모는 3,000억원을 상회하고 있다. 이러한 항균 가공제품이 호평을 받는 사회적 배경은 우리를 둘러싼 주변 삶의 경제환경 신장에 따른 쾌적성 추구와 밀접한 관련이 있을 것이다. 이처럼 항균기능이 부여된 제품이 호평을 받고 있음에도 불구하고 국내에서는 항균제품의 주 기능 역할을 하는 항균제에 대한 개발은 초기단계로 국내 시장에서 많은 연구가 이루어지고 있는 실정이다. 국내의 경우, 유기 항균제의 사용이 전체 사용량의 80%를 차지하고 있고, 제올라이트나 인산염을 무기 담체로 항균성 금속 이온(Ag, Zn)을 물리적으로 결합시킨 무기 항균제가 개발된 것이 최근의 기술 수준이다. 이러한 유기 항균제는 미생물의 번식을 억제 또는 사멸시키기 위한 것이지만, 생체의 피부 세포에도 영향을 줄 수 있는 피부 자극원의 하나로 그 사용이 점차로 제한되고 있다. 무기 항균제는 안정성이나 항균력에서는 유기항균제 보다는 뛰어나지만 가격(경제성)이나 색(Color), 사용성 (Application)측면에서는 여러 가지 문제를 나타내고 있다. 귀금속이므로 가격이 고가이며, 금속고유의 색으로 회귀하려는 플라즈몬 효과에 의해 색(Color)의 조절이 불가능, 분말형태이므로 지류에 첨가시키는 방법 등이 큰 문제로 부각되고 있다. 이 러한 문제점을 해결할 수 있는 기술이 나노기술이다 나노기술(Nano-Technology)은 물질을 분자, 원자단위에서 규명하고 제어하는 기술로서 원자, 분자를 적절히 결합시킴으로서 기존 물질의 변형, 개조는 물론 신물질의 창출을 가능케 하는 기술이다. 나노기술은 여러분야로 세분화되지만 그중 산업화에 가장 접목이 용이한 기술이 나노입자(Nano-Particle)제어 기술이며, 나노입자는 통상적으로 입자크기가 수 nm에서 100nm이하 크기의 넓은 표면적을 가진 콜로이드 상의 불균일 분산입자를 말한다. 나노입자(Nano-Particle)는 기존의 입자($\mu\textrm{m}$)보다 물리적 및 광학적 성질이 우수하고 그 자체의 기능면에서도 탁월하기 때문에 국내외의 여러 산업에서도 기존제품의 품질 향상 및 기능성부여, 기존 공정의 개선 및 생산 원단위 절감 등 경제적, 생산적인 측면을 고려하여 적합한 나노입자를 채택, 적용하고자 하는데 많은 노력을 기울이고 있다. 이에 천연 항생제로 알려진 Ag, 즉 항균 및 탈취, 전기적 기능이 우수한 은(silver, Ag)을 나노(nm) 입자희 제조하고 이와 더불어 이산화티탄(TiO2) 복합 분체를 제조하여 제조된 나노 입자 및 복합 분체를 사용함으로써 환경 친화적이며 다양한 용도로 활용 가능한 소재 개발에 연구 내용을 두고 있다. 본 연구를 통한 기대 효과로서 환경성 측면에서는 환경 친화적인 나노 입자의 제조로 기능성 나노 입자에 친 환경성을 부여하여 유기계 항균제 대체 효과를 발현하고 이를 제품에 적용함으로써 다양한 기능을 가진 신소재 제조에 있다. 또한 경제적인 측면에서도 고부가 가치의 제품 개발에 따른 새로운 수요 창출과 수익률 향상, 기존의 기능성 안료를 나노(nano)화하여 나노 입자를 제조, 기존의 기능성 안료에 대한 비용 절감 효과등을 유도 할 수 있다. 역시 기술적인 측면에서도 특수소재 개발에 있어 최적의 나노 입자 제어기술 개발 및 나노입자를 기능성 소재로 사용하여 새로운 제품의 제조와 고압 기상 분사기술의 최적화에 의한 기능성 나노 입자 제조 기술을 확립하고 2차 오염 발생원인 유기계 항균제를 무기계 항균제로 대체할 수 있다. 이와 더불어 안료의 형상 균일화 기술을 확보하여 가격 경쟁력 및 부가가치 향상을 기대할 수 있다.

• Journal of the Korea Concrete Institute
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• v.17 no.1 s.85
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• pp.77-84
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• 2005

The steel slag, a by-product which is produced by refining pig iron during the manufacture of steel, is mainly used as road materials after aging. It is necessary to age steel slag for long time in air because the reaction with water and free-CaO in steel slag could make the expansion of volume. This problem prevents steel slag from being used as aggregate for concrete. However, steel slag used in this study was controled by a air-jet method which rapidly cools substance melted at a high temperature. The rapidly-chilled method would prevent from generation of free-CaO in steel slag. This study dealt with the influence of the using rate of rapidly-chilled steel slag on flow, dosage of SP, W/C ratio, and strength of mortar by statistical experimental design. Also, the results of this experiment were approved by statistical analysis methods, such as analysis of variance and F-testing. As results of F-testing, this paper proved at $1\%$ level of significance that the more the using rate of rapidly-chilled steel slag increased, the more this affected the enhancement of flow, the decrease of dosage of SP and W/C ratio, and the development of compressive strength. Also, considering the fluidity and compressive strength of mortar, it is desirable to use $75\%$ of rapidly-chilled steel slag for river sand.

• Journal of Environmental Policy
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• v.5 no.4
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• pp.51-84
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• 2006

The current study suggested plans to maintain excellent natural environment of national parks by prohibiting excessive use and introduced the concept of environment capacity using GIS. This paper is that researches on National Parks in the past studied were mostly on the natural resources, human resources, facilities and visitors as well as standard for management of these issues from individual perspective, this study defined concept of integrated (principle of overlay) carrying capacity. It also estimated environmental ecological conservation value considering ecological conservation and environment-ecological index and estimated visit attraction index based on attraction value of nature and facilities in the parks. And it suggested management index as a management plan for effective analysis and management of carrying capacity. As a result, in case of Mt. Jiri National Park, Grade 5 area requiring inducement occupied 71% while Grade 1 area requiring dispersion occupied 0.1%, which means the necessity of appropriate dispersion in the site. Moreover, this research aims to find a monitoring method, utilizing the concept of ubiquitous, for the continuous systematic monitoring on immense natural resources, facilities, and visitors. The continuable national park management plan was proposed by establishing quantitative, and qualitative objective of the environment capacity from the decision based on GIS public opinions from the gathered information. Through the GIS public opinion system and ubiquitous based technology, I propose the effective management technology method for national park.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.56-65
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• 2019

This study examined effects of 12 weeks of body weight based combined exercise training (resistance training for 30 min, aerobic training for 30min) on body composition (% body fat, lean body mass, fat mass and BMI (body mass index)) and cardiovascular factors (ankle-brachial index (ABI) and brachial-ankle pulse wave velocity (baPWV)) in elderly women. A total of 32 subjects participated in this study, and were randomly divided into either exercise group (n = 16, EG) or control group (n = 16, CG). All variables at pre-test were analyzed by independent t-test for baseline test, and all data post the study period were analyzed by two-way repeated measures ANOVA with contrast testing (α = 0.05). Our results indicate that body composition (% body fat, lean body mass, fat mass and BMI) in both EG and CG do not differ significantly. However, the right and left sides of baPWV in EG was significantly reduced, as compared to CG. Taken together, these results indicate that combined exercise training for 12 weeks positively influences the cardiovascular factors, and may prevent cardiovascular diseases in elderly females (over 65 years), thereby resulting in increased quality of life for the elderly.