• Nuclear Engineering and Technology
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• 제44권6호
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• pp.597-610
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• 2012

The passive auxiliary feedwater system (PAFS) is one of the advanced safety features adopted in the APR+, which is intended to completely replace the conventional active auxiliary feedwater system. With an aim of validating the cooling and operational performance of PAFS, an experimental program is in progress at KAERI, which is composed of two kinds of tests; the separate effect test and the integral effect test. The separate effect test, PASCAL ($\underline{P}$AF$\underline{S}$ $\underline{C}$ondensing Heat Removal $\underline{A}$ssessment $\underline{L}$oop), is being performed to experimentally investigate the condensation heat transfer and natural convection phenomena in PAFS. A single, nearly-horizontal U-tube, whose dimensions are the same as the prototypic U-tube of the APR+ PAFS, is simulated in the PASCAL test. The PASCAL experimental result showed that the present design of PAFS satisfied the heat removal requirement for cooling down the reactor core during the anticipated accident transients. The integral effect test is in progress to confirm the operational performance of PAFS, coupled with the reactor coolant systems using the ATLAS facility. As the first integral effect test, an FLB (feedwater line break) accident was simulated for the APR+. From the integral effect test result, it could be concluded that the APR+ has the capability of coping with the hypothetical FLB accident by adopting PAFS and proper set-points of its operation.

• Journal of Information Science Theory and Practice
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• 제2권4호
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• pp.31-48
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• 2014

The proliferation of many interactive Topic Detection and Tracking (iTDT) systems has motivated researchers to design systems that can track and detect news better. iTDT focuses on user interaction, user evaluation, and user interfaces. Recently, increasing effort has been devoted to user interfaces to improve TDT systems by investigating not just the user interaction aspect but also user and task oriented evaluation. This study investigates the combination of the bag of words and named entities approaches implemented in the iTDT interface, called Interactive Event Tracking (iEvent), including what TDT tasks these approaches facilitate. iEvent is composed of three components, which are Cluster View (CV), Document View (DV), and Term View (TV). User experiments have been carried out amongst journalists to compare three settings of iEvent: Setup 1 and Setup 2 (baseline setups), and Setup 3 (experimental setup). Setup 1 used bag of words and Setup 2 used named entities, while Setup 3 used a combination of bag of words and named entities. Journalists were asked to perform TDT tasks: Tracking and Detection. Findings revealed that the combination of bag of words and named entities approaches generally facilitated the journalists to perform well in the TDT tasks. This study has confirmed that the combination approach in iTDT is useful and enhanced the effectiveness of users' performance in performing the TDT tasks. It gives suggestions on the features with their approaches which facilitated the journalists in performing the TDT tasks.

• Corrosion Science and Technology
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• 제8권6호
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• pp.217-222
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• 2009

The production of advanced high strength steels requires the improvement of cooling technology. The use of high cooling rates allows relatively low levels of expensive alloying additions to ensure sufficient hardenability. In classical annealing and hot-dip galvanizing lines a mixing station is used to provide atmosphere gas containing 3-5% hydrogen and 97-95% nitrogen in the various sections of the furnace, including the rapid cooling section. Heat exchange enhancement in this cooling section can be insured by the increased hydrogen concentration. Drever International developed a patented improvement of cooling technology based on the following features: pure hydrogen gas is injected only in the rapid cooling section whereas the different sections of the furnace are supplied with pure nitrogen gas; the control of flows through atmosphere gas management allows to get high hydrogen concentration in cooling section and low hydrogen content in the other furnace zones. This cooling technology development insures higher cooling rates without additional expensive hydrogen gas consumption and without the use of complex sealing equipments between zones. In addition reduction in electrical energy consumption is obtained. This atmosphere control development can be combined with geometrical design improvements in order to get optimised cooling technology providing high cooling rates as well as reduced strip vibration amplitudes. Extensive validation of theoretical research has been conducted on industrial lines. New lines as well as existing lines, with limited modifications, can be equipped with this new development. Up to now this technology has successfully been implemented on 6 existing and 7 new lines in Europe and Asia.

• 복식
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• 제60권9호
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• pp.162-175
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• 2010

An important change started in knitwear fashion in the 1980s. Advanced designers in Japan began to provide a new interpretation on knitwear, and seamless knitwear based on computerized machinery appeared. Knitwear fashion showed differences starting the 1980s due to this change. In this regard, the study aimed to analyze knitwear fashion after the 1980s where the contemporary knitwear experienced changes to define characteristics of modern knitwear fashion and examine its inherent formative nature. Designs for 30 years from 1980s up to date have been analyzed by 10 years in order to identify the characteristics of knitwear fashion over time. In particular, formative characteristics of modern knitwear fashion have been analyzed in more depth with a focus on the period from 2001 through 2010 by narrowing the whole period. Insufficient domestic literatures and visual materials led the study to mostly use foreign books and internet sites. Insights of 7 professionals who have engaged themselves in knitwear industry over 10 years have been incorporated into this study, which will enhance the reliability of the formative analysis. As a result, the data have been organized into three tools of analysis, including exposed bodies, transformed bodies and natural bodies from the perspectives of expression and silhouette of body, and the features of flexibility, industrial artistry, innovation and sensuality have been highlighted in terms of formativeness. In this regard, it has been confirmed that the formative nature found in the knitwear fashion exists in the scope of the formative nature in the embryonic period of the knitwear fashion. It means that the formative nature of knitwear fashion contains perpetuity that transcends an age.

• 복식
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• 제64권8호
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• pp.111-123
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• 2014

The purpose of this research is to prepare basic data necessary to develop uniform design by examining the uniforms of Korean and Chinese airline crew. Advanced research, various literature materials related to uniform, as well as a survey on the images portrayed by the different uniforms of the airlines were used as research method, and this was used to investigate its functions and components. The survey was conducted in Incheon International Airport and Gwangju airport from September 1st to 30th of 2013, - targeting 350 people consisting of Koreans, Chinese, and other nationalities who have the experience of using Korean and Chinese aircraft. The research findings are summarized as follows. First, the images of the uniforms were classified into 5 elements: attractiveness, activity, noticeability, femininity, and traditionality. The analysis showed that Korean uniforms, except for Jin Air, received high marks overall, while the Chinese uniforms received lower marks compared to their Korean counterparts. Second, the results were analyzed based on the nationality of the respondents. In regards to Korean airline crews, attractiveness, activity, noticeability, femininity, and traditionality showed statistical significance with Korean respondents, while the significance was seen in attractiveness, activity, femininity, and traditionality for the Chinese respondents. Femininity was the only feature with any significance for the third nation respondents. On the other hand, with regard to Chinese airline crew's uniform, Korean respondents showed statistical significance in the following features: attractiveness and traditionality, while the Chinese and the third nation respondents did not show any statistical significance in any of the elements.

• 한국조경학회지
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• 제29권6호
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• pp.1-10
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• 2002

The purpose of this study is to establish a model of cultural sustainability in the traditional village. Cultural sustainability is being advanced by promoting the viability of traditional arts and the unique regional features of traditional culture, such as folklore, traditional landscapes, buildings and other environments of outstanding historical value. These cultural resources were also created or occurred at specific geographic locations at certain points in time by different individuals. The content of this study was to develop a model using indicators for cultural sustainability, and to apply and evaluate the model. In older to evaluate the model, Sonwon-ri village in Yongchon, located in Kyungsangbuk-do, was selected as the case study area. The major findings are as follows: 1) Sonwon-ri village has maintained the vernacular landscape except at the entrance of village. Also, the village people have pride and have adapted to the natural environment. 2) Sonwon-ri village has a self-sustaining system and circular network within its environmental capacity. Sonwon-ri village has many historical sites and buildings such as important folk resources, cultural assets, traditional houses and pavilions. 3) The people how the theory of fens-shui which interprets the location of village in relationship to a crane mountain with the village situated as a crane head. These symbolic and cultural elements have an important role in establishing the boundary of the village. From the research it can be seen that Sonwon-ri village kept many cultural sustainability indicators in terms of active factors, physical factors and psychological factors. By analysing the participation of different scientific disciplines and identifying disciplinary categories, this study provides a basis for understanding how cultural sustainability is subjected to research in the field of landscape planning and design.

• 정보처리학회논문지D
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• 제9D권4호
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• pp.619-628
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• 2002

소프트웨어 부품화는 소프트웨어 개발에 있어서의 궁극적인 목표이다. 컴포넌트 기반의 개발은 이러한 재사용의 초점을 코드에 의한 수동적인 조작이나, 클래스 라이브러리보다 발전된 형태인 컴포넌트에 초점을 두고 있다. 컴포넌트 구축은 컴포넌트 모델에 적합한 새로운 소프트웨어 컴포넌트를 재개발 해야하는 비효율성으로 인해 추가적인 노력과 비용을 야기 시킨다. 최근 많이 사용되고 있는 자바 응용시스템의 경우 자바 언어 기반의 컴포넌트 모델이 존재하지만, 소규모의 재사용 단위나 제한된 GUI 컴포넌트 개발에만 머무르고 있어, 컴포넌트로의 기능을 충분히 발휘하지 못하거나 추가적인 비용, 노력이 필요하며 또한 특정 도메인 컴포넌트에서만 제한적이다는 단점이 있다. 따라서, 본 논문에서는 기존의 자바로 개발된 응용시스템을 기반 하여 자바의 컴포넌트 모델인 자바빈즈를 적용하기 위해, 컴포넌트를 확장 추출하고, 재사용단위로서 비즈니스 로직의 부분적인 수용을 통해 이 응용시스템에서의 자바빈즈로 변환하는 프로세스를 제시하고 알고리즘을 제안한다.

• Advances in concrete construction
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• 제8권3호
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• pp.225-237
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• 2019

Although applying self-consolidating concrete (SCC) in many modern structures is an inevitable fact, the high consumption of cement in its mixing designs has led to increased production costs and adverse environmental effects. In order to find economically viable sources with environmentally friendly features, natural pozzolan pumice and blast furnace slag in 10-50% of replacement binary designs have been investigated for experiments on the properties of fresh concrete, mechanical properties, and durability. As a natural pozzolan, pumice does not require advanced equipment to prepare for consumption and only needs to be powdered. Pumice has been the main focus of this research because of simple preparation. Also to validate the results, in addition to the control specimens of each design, fly ash as a known powder has been evaluated. Moreover, ternary mixes of pumice and silica fume were investigated to enhance the obtained results of binary mixes. It was concluded that pumice and slag powders indicated favorable performance in the high percentage of replacement.

• 한국항행학회논문지
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• 제23권5호
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• pp.430-436
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• 2019

해상 및 산업 현장의 다양한 IoT 서비스를 위한 시스템에 필수불가결한 장치인 안테나 개발에 있어 초소형, 경량 및 다중 대역 동작이 요구된다. 이러한 요구를 반영할 수 있는 대표적인 안테나의 한 종류가 PCB 패턴 안테나이다. 본 연구에서는 920 MHz 단일 대역 PCB 패턴 안테나의 설계 및 제작에 대하여 살펴보았다. 제안된 920 MHz 단일 대역 안테나의 PCB 패턴을 260 MHz 대역에서도 동작하도록 수정 보완하여 이중 대역 PCB 패턴 안테나를 제작하는 것이 최종 목표이다. 본 연구를 통해 920 MHz의 ISM 대역 중 902 MHz, 915 MHz와 928 MHz에서 우수한 성능을 얻을 수 있었다. 또한 전압 정재파비, 반사 손실, 이득과 효율 등의 주파수별 차이가 5% 미만이었다. 이러한 결과를 -30 dB의 수신 감도를 갖는 LPWA (low power wide area) 네트워크에 적용하면 최소 5-10 km의 통신 링크 구축이 가능할 것으로 예측할 수 있다.

• The Journal of Advanced Prosthodontics
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• 제14권2호
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• pp.96-107
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• 2022

PURPOSE. Microstructural and physico-mechanical characterization of highly translucent zirconia, prepared by milling technology (CAD-CAM) and repeated firing cycles, was the main aim of this in vitro study. MATERIALS AND METHODS. Two groups of samples of two commercial highly-translucent yttria-stabilized dental zirconia, VITA YZ-HT^White (Group A) and Zolid HT + White (Group B), with dimensions according to the ISO 6872 "Dentistry - Ceramic materials", were prepared. The specimens of each group were divided into two subgroups. The specimens of the first subgroups (Group A₁ and Group B₁) were merely the sintered specimens. The specimens of the second subgroups (Group A₂ and Group B₂) were subjected to 4 heat treatment cycles. The microstructural features (microstructure, density, grain size, crystalline phases, and crystallite size) and four mechanical properties (flexural strength, modulus of elasticity, Vickers hardness, and fracture toughness) of the subgroups (i.e. before and after heat treatment) were compared. The statistical significance between the subgroups (A₁/A₂, and B₁/B₂) was evaluated by the t-test. In all tests, P values smaller than 5% were considered statistically significant. RESULTS. A homogenous microstructure, with no residual porosity and grains sized between 500 and 450 nm for group A and B, respectively, was observed. Crystalline yttria-stabilized tetragonal zirconia was exclusively registered in the X-ray diffractograms. The mechanical properties decreased after the heat treatment procedure, but the differences were not statistically significant. CONCLUSION. The produced zirconia ceramic materials can be safely (i.e., according to the ISO 6872) used in extensive fixed prosthetic restorations, such as substructure ceramics for three-unit prostheses involving the molar restoration and substructure ceramics for prostheses involving four or more units. Consequently, milling technology is an effective manufacturing technology for producing zirconia substructures for dental fixed all-ceramic prosthetic restorations.