• Journal of Advanced Marine Engineering and Technology
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• 제10권2호
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• pp.156-164
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• 1986

In the case of boiling on high temperature wall, vapor film covers fully or parcially the surface. This phenomenon, film boiling or transition boiling, is very important in the surface heat treatment of metal, design of cryogenic heat exchanger and emergency cooling of nuclear reactor. Mainly supposed hydraulic-thermal accidents in nuclear reactor are LCCA (Loss of Coolant Accident) and PCM (Power-Cooling Mismatch). Recently, world-wide studies on reflooding of high temperature rod bundles after the occurrence of the above accidents focus attention on wall temperature history and required time in transient cooling process, wall superheat at rewet point, heat flux-wall superheat relationship beyond the transition boiling region, and two-phase flow state near the surface. It is considered that the further systematical study in this field will be in need in spite of the previous results in ref. (2), (3), (4). The paper is the study about the fast transient cooling process following the wall temperature excursion under the CHF (Critical Heat Flux) condition in a forced convective subcooled boiling system. The test section is a vertically arranged concentric annulus of 800 mm long and 10 mm hydraulic diameter. The inner tube, SUS 304 of 400 mm long, 8 mm I.D, and 7 mm O.D., is heated uniformly by the low voltage AC power. The wall temperature measurements were performed at the axial distance from the inlet of the heating tube, z=390 mm. 6 chromel- alumel thermocouples of 76 .mu.m were press fitted to the inner surface of the heating tube periphery. To investigate the heat transfer characteristics during the fast transient cooling process, the outer surface (fluid side) temperature and the surface heat flux are computed from the measured inner surface temperature history by means of a numerical method for inverse problems of transient heat conduction. Present cooling (boiling) curve is sufficiently compared with the previous results.

• The Plant Pathology Journal
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• 제35권6호
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• pp.553-563
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• 2019

Investigations related with factors influencing root and crown rot are rare and mainly related to farming practice and soil management. The main objective of this study was to examine broader range of factors influencing stem-base infestation of winter wheat in the field conditions. The effect of spatial distribution of infected plants on disease index (DIs) assessments was also investigated. Analysis of factors influencing DIs of crown rot of wheat demonstrated significant influence of the growing seasons (P < 0.001) and extreme fluctuations in winter temperatures (P < 0.001). In addition to that, localities together with their interaction with the growing season also significantly influenced DIs (P < 0.001). Aggregation of infected plants influenced variability of DI estimations, and it was pointed out that more extensive investigation should be conducted on broad range of DI in order to establish sampling method giving uniform sampling precision. Fusarium graminearum was shown to be predominant Fusarium species in Serbia (72.6%) using sequence-characterized amplified region analysis. Interestingly F. oxysporum was isolated in higher frequencies (27.4%) than it was reported in the literature. Given that there were no reports on the diversity of Fusarium species causing crown rot of wheat in Serbia, this study presents first report on this important subject. It also indicated that more attention should be focused on combined effects of abiotic and biotic factors influencing stem-base infestation of winter wheat. This knowledge will contribute to better understanding of factors influencing root and crown rot of wheat which would ensure sustainable disease management in the future.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.3863-3868
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• 2012

In this study mitochondrial D-Loop variations in Iranian prostate cancer and benign prostatic hyperplasia (BPH) patients were investigated. Tumour samples and corresponding non-cancerous prostate tissue from 40 prostate cancer patients and 40 age-matched BPH patients were collected. The entire mtD-loop region (16024-576) was amplified using the PCR method and products were gel-purified and subjected to direct nucleotide sequencing. A total of 129 variations were found, the most frequent being 263A${\rightarrow}$G and 310T${\rightarrow}$C among both BPH and prostate cancer patients. Variation of 309 C${\rightarrow}$T was significantly more frequent in prostate cancer patients (P value<0.05). Four novel variations were observed on comparison with the MITOMAP database. Novel variations were np16154delT, np366G${\rightarrow}$A, np389G${\rightarrow}$A and 56insT. There was no correspondence between the different variations and the age of subjects. Considering that D-loop variations were frequent in both BPH and prostate cancer patients in our study, the fact that both groups had high average age can be a possible contributing factor. D-loop polymorphisms and microsatellite instability can influence cell physiology and result in a benign or malignant phenotype. Significantly higher frequency of 309 C${\rightarrow}$T variation in cancer patients is a notable finding and must be a focus of attention in future studies.

• 대한인간공학회지
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• 제31권6호
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• pp.705-713
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• 2012

Objective: The aim of this study is to predict human visual target search using ACT-R cognitive architecture in real scene images. Background: Human uses both the method of bottom-up and top-down process at the same time using characteristics of image itself and knowledge about images. Modeling of human visual search also needs to include both processes. Method: In this study, visual target object search performance in real scene images was analyzed comparing experimental data and result of ACT-R model. 10 students participated in this experiment and the model was simulated ten times. This experiment was conducted in two conditions, indoor images and outdoor images. The ACT-R model considering the first saccade region through calculating the saliency map and spatial layout was established. Proposed model in this study used the guide of visual search and adopted visual search strategies according to the guide. Results: In the analysis results, no significant difference on performance time between model prediction and empirical data was found. Conclusion: The proposed ACT-R model is able to predict the human visual search process in real scene images using salience map and spatial layout. Application: This study is useful in conducting model-based evaluation in visual search, particularly in real images. Also, this study is able to adopt in diverse image processing program such as helper of the visually impaired.

• 한국환경복원기술학회지
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• 제21권5호
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• pp.17-28
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• 2018

Cyclonic-dissolved air flotation(Cyclonic-DAF), an advanced form of pressure flotation, applies a structure that enables the forming of twirling flows. This in turn allows for suspended matter to adhere to microbubbles and float to the surface of a treatment tank during the process of intake water flowing through a float separation tank. This study conducted a lab-scale test and pursued geometrical modeling using computational fluid dynamics(CFD) to establish a pilot scale design. Based on the design parameters found through the above process, a pilot cyclonic-DAF system($10m^3/hr$) for removing algae was created. Upon developing the pilot-scale cyclonic-DAF system, a type of algae coagulant(R-119) was applied as the coagulant to the system for field testing through which the removal rates of chlorophyll-a and cyanobacteria were evaluated. The chlorophyll-a and harmful cyanobacteria of the raw water at region B, the field-test site, were found to be $177.9mg/m^3$ and 652,500cells/mL respectively. Treated waters applied with 60mg/L and 100mg/L of algae coagulant presented removal efficiencies of approximately 95% and 97%, respectively. The cyanobacteria cell number of the treated waters applied with 60mg/L and 100mg/L of algae coagulant both that were equal to or less than 1,000cells/mL and were below attention level criteria for the issuance of algae boundary.

• 대한원격탐사학회지
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• 제36권2_2호
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• pp.231-236
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• 2020

최근 지구온난화로 인한 지구 규모 단위의 기후변화로 인한 연안의 환경변화에 대한 관심이 매우 높다. 또한 인간의 도시 개발로 인해 중요한 자연 및 사회적으로 유용한 연안지역 환경이 많이 훼손되고 있다. 이를 보호하기 위한 다양한 플랫폼과 탑재체를 이용한 현장 조사 및 원격탐사 연구가 연안 및 근해 지역에서 수행되고 있다. 본 특별호는 한국해양과학기술원 해양위성센터와 그 외 여러 대학에서 진행되고 있는 다양한 주제의 흥미로운 연안원격탐사 연구 결과를 소개한다. 본 특별호를 통해 한국해양과학기술원 해양위성센터에서 수행되고 있는 다양한 국내 연안원격탐사의 역할과 가치를 공유하고 연안 환경을 보호하기 위한 연안원격탐사 과제 발굴을 위한 계기가 되기를 기대한다.

• 한국학교보건학회지
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• 제19권2호
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• pp.105-115
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• 2006

Purpose：This thesis was performed to evaluate the effect of the experience safety education on the safety behavior and standard of habit to the middle school students of one islands. Methods：The participants of this study included 43, located in the adjoining region in S county. While one of the class, composed of 19 students was designated as an experimental group, and the other class, composed of 24 students, was compared as a control group. Used program in this study was safety education program, 'Safe School, Safe Life' which was developed by Korea Occupational Safety & Health Agency. This program has emphasis on the virtual case rather than lecture style education. Results：The findings in this research were as follows. Indoor safety behavior was significant difference between the two groups. On the other hand, the effect on outdoor safety behavior was not difference. In playground case, active strength was needed without continuous attention. The effect of the experience safety behavior education was not shown in the area of traffic rules, pedestrian safety, and vehicle safety. But home safety behavior was effective. Education program on the manners of standard life habit gives positive results. But in the area of rules, this program was not effective, since students had tendency to emphasize the rigid scale rather than manners. Conclusion：These findings in the study give us the necessity of experience safety education program to prepare various situations of everyday life and to reinforce safety behavior and improve standard life habit.

• 천문학회지
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• 제36권2호
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• pp.55-60
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• 2003

In Lee, Kang & Byun (2001) the discovery of Raman scattered 6545 A feature was reported in symbiotic stars and the planetary nebula M2-9. The broad emission feature around 6545 A is formed as a result of Raman scattering of He II n = 6 $\to$ n = 2 photons by atomic hydrogen. In this paper, we introduce a method to compute the equivalent width of He II $\lambda$ 1025 line and present an optical spectrum of the symbiotic star RR Telescopii as an example for a detailed illustration. In this spectrum, we pay attention to the broad H$\alpha$ wings and the Raman scattered He II 6545 feature. The broad Ha wings are also proposed to be formed through Raman scattering of continuum around Ly$\beta$ by Lee (2000), and therefore we propose that the equivalent width of the He II $\lambda$ 1025 emission line is obtained by a simple comparison of the strengths of the 6545 feature and the broad H$\alpha$ wings. We prepare a template H$\alpha$ wing profile from continuum radiation around Ly$\beta$ with the neutral scattering region that is supposed to be responsible for the formation of Raman scattered He II 6545 feature. Isolation of the 6545 feature that is blended with [N II] $\lambda$ 6548 is made by using the fact that [N II] $\lambda$ 6584 is always 3 times stronger than [N II] $\lambda$ 6548. We also fit the 6545 feature by a Gaussian which has a width 6.4 times that of the He II $\lambda$ 6527 line. A direct comparison of these two features for RR Tel yields the equivalent width $EW_{Hel025} = 2.3{\AA}$ of He II $\lambda$ 1025 line. Even though this far UV emission line is not directly observable due to heavy interstellar extinction, nearby He II lines such as He II $\lambda$ 1085 line may be observed using far UV space instruments, which will verify this calculation and hence the origins of various features occurring in spectra around H$\alpha$.

• 한국중재학회지:중재연구
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• 제15권3호
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• pp.233-266
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• 2005

The world trading system has been under many changes in recent years. One notably important development is that much attention away from the multilateralism-oriented World Trade Organization towards FTA(Free Trade Agreement). The Free Trade Agreement signed between korea and chile formally have been come effective for free trade in goods and services as from April 1, 2004. During Free Trade Agreement negotiations between both countries. This study aims at presenting the suggestion for the Korea to make the WTO rules and FTA by analyzing The interpretation of FTA under WTO System. It was founded by the investigation of WTO rules, most of the provisions are similar with other FTA, but a little provisions different from other FTA's. It is an appearance from the contracting party's peculiar circumstances such as state of industrial development or future prospect, conditions around international trade. The whole world has entered the new stage of bilateral and multilateral FTA. The essential or new generation or bilateral and multilateral FTA is creating more trade opportunities, promoting all factors, commodity, service, capital, technology and talent freely flow through canceling the trade barriers between FTA, in order to develop together within the regions. It shows that the cooperations transfer form the whole region into FTA. FTA makes not only the free trade smooth ,but also takes place the trade distortion effect. especially as the agriculture has a speciality each country, should it is ignored in negotiation, many reactions will be occurred in the process of fta Therefore Korea needs to deliver the message that Korea's hub is an essential ingredient for an efficient FTA and WTO system in a bilateral and multilateral win-win framework. Consequently Korea should have criterions about the rules of FTA and WTO system for peculiar circumstances of Korean economy and international trade.

• 한국경제지리학회지
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• 제2권1_2호
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• pp.123-144
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• 1999

본 연구는 통합여수시를 사례로 도시생활환경의 측정 및 삶의 질 변화에 대한 도시민의 인식.평가의 변화를 설문조사를 통해 살펴보았고, 이를 바탕으로 지역주민의 삶의 질을 향상시킬 수 있는 정책적 대안을 제시하였다. 통합여수시의 삶의 질은 5년 전에 비해서 전체적으로 삶의 질은 향상된 것으로 분석되었다. 그러나 삶의 질에 관한 9개 지표 중에서 주거생활, 도시행정 및 편익서비스 등은 5년전보다 상대적으로 향상된 반면, 자연환경, 문화 및 여가생활, 교통환경 등은 나빠진 것으로 평가하였다. 그리고 여수시민들은 통합여수시의 지속적인 발전을 도모하기 위해서는 교통문제, 문화 및 여가시설의 확충 등이 주요한 과제라고 인식하였고, 21세기의 통합여수시가 해양관광도시, 교육문화도시로 발전하기를 선호하였다. 따라서 여수대도시권을 구축율 위한 주요 과제로는 경제기반시설의 확충, 워터프런트의 개발 및 보전, 관광산업의 활성화, 시민중심의 도시경관 조성, 지역문화운동의 전개 등이 필요한 것으로 밝혀졌다.