• Corrosion Science and Technology
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• 제3권5호
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• pp.198-208
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• 2004

Although there has been no general agreement on the mechanism of primary water stress corrosion cracking (PWSCC) as one of major degradation modes of Ni-base alloys in pressurized water reactors (PWR's), common postulation derived from previous studies is that the damage to the alloy substrate can be related to mass transport characteristics and/or repair properties of overlaid oxide film. Recently, it was shown that the oxide film structure and PWSCC initiation time as well as crack growth rate were systematically varied as a function of dissolved hydrogen concentration in high temperature water, supporting the postulation. In order to understand how the oxide film composition can vary with water chemistry, this study was conducted to characterize oxide films on Alloy 600 by an in-situ Raman spectroscopy. Based on both experimental and thermodynamic prediction results, Ni/NiO thermodynamic equilibrium condition was defined as a function of electrochemical potential and temperature. The results agree well with Attanasio et al.'s data by contact electrical resistance measurements. The anomalously high PWSCC growth rate consistently observed in the vicinity of Ni/NiO equilibrium is then attributed to weak thermodynamic stability of NiO. Redox-induced phase transition between Ni metal and NiO may undermine the integrity of NiO and enhance presumably the percolation of oxidizing environment through the oxide film, especially along grain boundaries. The redox-induced grain boundary oxide degradation mechanism has been postulated and will be tested by using the in-situ Raman facility.

• 한국항만경제학회지
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• 제30권4호
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• pp.91-110
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• 2014

정부는 주요항만 배후단지를 활성화하기 위해 항만배후단지에 물류와 비즈니스의 연계강화를 통한 '국제 항만물류 비즈니스 클러스터'를 구상하고 있고, 이를 위해 업무 편의시설 조성을 계획하고 있다. 한국의 주요항만과 경쟁하고 있는 유럽, 중국, 일본 등의 항만들도 항만도시로의 발전을 위해 항만배후단지에 업무 편의시설을 개발하고 있다. 본 연구는 국내외 업무 편의에 대한 사례분석과 광양항 업무 편의시설에 대한 수요추정을 통해 광양항 업무 편의시설의 활용방안, 개발단계, 운영방안 등을 제시한다. 광양항 업무 편의 시설은 업무 숙박 상업시설 중심의 개발이 필요하며, 수요를 추정한 결과 2035년을 목표로 단계적으로 개발되어야 할 것으로 추정되었다. 또한 토지임대시 수익성 있는 토지임대료를 책정하고, 조기활성화를 위한 인센티브제를 고려할 필요가 있을 것이다. 민간분양을 위해서는 항만배후부지에 대행개발 등의 민간투자를 허용하는 방향으로의 항만법의 추후 개정도 논의되어야 할 것이다.

• 한국안전학회지
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• 제35권5호
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• pp.30-38
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• 2020

In order to construct a dam, the diversion facility such as cofferdam and a diversion tunnel should be installed in advance. And size of a cofferdam depends on type of a main dam. According to the Korea Dam Design Standard, if the main dam is a concrete dam, design flood of the cofferdam is 1~2 years flood frequency. This means that overflow of the cofferdam occurs one time for 1 or 2 years, therefore, stability of the cofferdam should be secured against any overflow problem. In this study, failure probability analysis for the concrete cofferdam is performed considering the overflow. First of all, limit state function of the concrete cofferdam is defined for overturning, sliding and base pressure, and upstream water levels are set as El. 501 m, El. 503 m, El. 505 m, El. 507 m. Also, after literature investigation research, probabilistic characteristics of various random variables are determined, the failure probability of the concrete cofferdam is calculated using the Monte Carlo Simulation. As a result of the analysis, when the upstream water level rises, it means overflow, the failure probability increases rapidly. In particular, the failure probability is largest in case of flood loading condition. It is considered that the high upstream water level causes increase of the upstream water pressure and the uplift pressure on the foundation. In addition, among the overturning, the sliding and the base pressure, the overturing is the major cause for the cofferdam failure considering the overflow.

• 농촌계획
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• 제26권3호
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• pp.39-47
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• 2020

While agricultural water has been declared free in Korea to ensure access to these limited resource since the year 2000, farmers have however developed lackadaisical behavior towards water saving leading to its scarcity. To overcome this problem, a variety of experience-oriented education model was developed for farmers to promote the adoption of water conservation, and preventive measure against the drought impacts. In this study, farmers' awareness and their attitudinal behavior of agricultural water savings were investigated. The monitoring of water supply structure and the repair facilities in Pohang and Yeongdeok areas were conducted. The field visits and behavioral surveys showed a high degree of over-use and illegal water withdrawals by the farmers due to poor water-saving and management practices. We found that most of the KRC employees strongly admitted the necessity of water-saving education. On the other hand, the farmers showed good interest in the implementation of water-saving awareness through education. Besides this, most farmers agreed to adopt water-saving practices in the fields. Farmers also acknowledged the recklessness of water use was due to the aging of waterways, poor water management, and illegal water consumption. The majority of the farmers responded against imposing the water-use tariffs. However, there was a low response to paying the water-use charge. Aging agricultural facilities and the lack of institutional penalties or incentives were the major obstacles in achieving efficient water-saving. Considering the current drought frequency, urgent water-saving education of farmers was deemed necessary to prepare the farming community against the water shortages. Based on the results of this study, we have to identify the irrigation practices of farmers and provide water-saving education to enforce more efficient use and management of agricultural water.

• 한국환경과학회지
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• 제27권11호
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• pp.947-956
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• 2018

Trains have been a major means of transport in Korea during these past decades. However, train facilities such as stations and repair shops are contaminated with organic and inorganic substances. There is a high probability of train facility contamination with polyaromatic hydrocarbons (PAHs). This study evaluated the PAH and heavy metal contamination of soil near railroads in the Kyungpook area. A total of 18 soil samples were collected from the railroads and analyzed for 16 PAHs and 6 heavy metal species. The contamination level of the top soil was found to be slightly higher than that of the subsoil for contamination with PAHs. The ratio of carcinogenic PAH concentration to the total PAH concentration was relatively high, with a maximum of 0.9. The toxicity equivalent (TEQ) of the PAHs were 500.6 ng/kg in the topsoil and 355.5 ng/kg in the subsoil. The ratio of low molecular PAHs (LPAHs) to high molecular PAHs (LPAHs) ranged from 6.7 to 29.5; this shows that contamination is primarily due to combustion of fuel rather than due to petroleum. The ratio of phenanthrene to anthracene and the ratio of fluoranthene to pyrene also show that contamination occurred due to combustion for transportation. The heavy metal contamination level was lower than the Korean standard, but higher than the background concentration; this indicates that the soil was affected by the operation of the railways.

• 품질경영학회지
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• 제49권2호
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• pp.127-143
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• 2021

Purpose: Smart Safety Living Lab is a Living Lab facility, constructed and operated by KITECH in Korea, to support the user experience(UX) evaluation, planning and certification of smart safety products and services. The purpose of this study is to develop a UX evaluation methodology that accommodates the characteristics of the Living Lab and smart safety products and services for a systematic and efficient UX evaluation in the Smart Safety Living Lab. Methods: A generic model of UX evaluation was first derived based on a review of related literature. Then, the generic model is revised to accommodate the characteristics of the Smart Safety Living Lab and smart safety products and services, resulting in the UX Evaluation Methodology for Smart Safety Living Lab (SSLL-UXEM). Results: The developed SSLL-UXEM consists of a structured process for UX evaluation, a guideline for conducting each step of the process, and a set of forms for recording the major evaluation results in each step. Conclusion: SSLL-UXEM can help to enhance the efficiency of the UX evaluation process and the consistency of the UX evaluation results. SSLL-UXEM is also expected to serve as a basis for UX evaluation in various living lab environments in the future.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제47권6호
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• pp.432-437
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• 2021

Objectives: The mandible and other parts of the maxillofacial region suffer significant morbid injuries following road traffic accidents. Our study gives epidemiological description of mandibular fractures in Ghana and also evaluates the relevance of closed reduction and indirect fixation for managing mandibular fractures in low-resource health facilities in low-income countries like Ghana. Patients and Methods: This is a retrospective study involving 268 patients who reported to the Department of Oral and Maxillofacial Surgery of the Sunyani Regional Hospital with mandibular fractures from January 2010 to December 2019. Patient medical records were assessed for information on age, sex, fracture etiology, anatomic location of fracture, time of day of road traffic accident, and other associated injuries. Results: A total of 268 patients were included in this study (males, 216 [80.6%]; females, 52 [19.4%]). Motor vehicular accident (MVA) was the leading cause of mandibular fractures (202 injuries, 75.4%). Other etiologies included assault (39, 14.6%), gunshot (13, 4.9%), falls (12, 4.5%), and industrial accidents (2, 0.7%). Of the 161 male cases caused by MVA, 121 (75.2%) occurred at night and in the evening while the remaining 40 (24.8%) occurred in the morning and afternoon. Among all managed 222 patients, 212 (79.1%) were treated with closed reduction and indirect fixation technique while 10 (3.7%) were treated with open reduction and direct fixation. Conclusion: Closed reduction with indirect fixation could successfully be used to manage mandibular fractures in low resourced health facilities, especially in low-income countries. The poor lightening system on roads in Ghana is a major contributory factor to motor vehicular accidents.

• 대한영양사협회학술지
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• 제30권2호
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• pp.83-94
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• 2024

Nutrition education is essential for the health of people with disabilities. This paper presents nutrition education topics and operational directions for people with disabilities living in social welfare facilities for people with disabilities. This study was conducted through one-on-one, in-depth interviews with 11 operators and workers at social welfare facilities where people with disabilities reside. They were asked about the current status of nutrition education at the social welfare facility for people with disabilities where the interviewee works, major diseases of residents, topics of nutrition education needed, and preferred education methods to determine the type of nutrition education for people with disabilities needed in the field. As a topic of nutrition education, dietary education for obesity prevention and management was most requested, and education on basic nutritional ingredients was also desired. It was mentioned that the educational level would be appropriate for children aged 6~9, and using materials that would attract interest was recommended. Activity-based face-to-face education was preferred for the operation of the program, and it was mentioned that education would be possible in a short period. In addition, it was mentioned that nutrition education is necessary for people with disabilities and workers at social welfare facilities for people with disabilities. Confirming the topic and operation direction of the nutrition education program required by social welfare facilities for people with disabilities will make it possible to contribute to providing nutrition education tailored to social welfare facilities for people with disabilities in Korea.

• 생태와환경
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• 제43권1호
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• pp.44-54
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• 2010

본 연구에서는 전극 4대강 권역 6개 주요 수계(남한강, 낙동강, 남강, 금강, 영산강 및 섬진강)의 본류를 대상으로 하여 공간분석과 현장조사 및 평가를 통한 강변저류지 조성 후보지를 결정하였다. 강변저류지는 하천변에 배후습지와 연결될 수 있는 대규모 인공습지의 형태로, 홍수조절, 용수공급, 수질정화, 생태문화공간 제공 등 다기능의 목적을 갖고 있다. 또한 조성된 강변저류지는 배후습지로서의 역할 역시 수행이 가능하여, 수문학적 및 생태학적 관점에서 상당히 높은 효율성을 갖는 요소이다. 따라서 강변저류지 조성 효과를 높이기 위한 선행적 절차는 조성 후보지를 선정하는 것이다. 본 연구에서는 지리정보와 현장특성 (생태계 연결성, 교육-문화적 여건 등)을 종합적으로 파악하여 분석을 실시하였다. GIS 분석 결과, 각 수계별로 남한강 $71.5\;km^2$, 낙동강 $54.1\;km^2$, 남강 $2.3\;km^2$, 금강 $79.0\;km^2$, 영산강 $46.4\;km^2$, 섬진강 $15.7\;km^2$ 수준의 강변저류지 가능지역이 탐색되었으며, 위치상으로는 중하류부의 하천 합류부 등에서 넓게 분포하는 패턴을 보였다. 이 결과를 바탕으후 총 106개 지점에 대한 현장조사를 실시한 결과, 대체로 남강, 금강 등의 수계에서 배후습지로서 양호한 기능이 기대되는 강변저류지 가능 지점이 주로 분포하였다. 특히 현장 조사 중 낙동강, 섬진강 수계의 일부 지점은 인곤 습지 서식처(우포 등)와의 연계성, 주요 생물분류군 서식처와의 인접성(수달 서식처 등), 문화재 및 생태환경 교육여건(생태학습관, 사찰 등) 이 잘 구축된 경우로 파악되어 매우 양호한 것으로 사료된다. 향후 이들 지점에 대해서 정밀한 수문학적 고찰이 진행될 경우 보다 수문-생태-문화-교육 차원에서 효율적인 강변저류지의 조성이 가능할 것으로 기대된다.

• 가정과삶의질연구
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• 제26권5호
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• pp.195-209
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• 2008

The purpose of this study was to provide basic information about design guidelines of activity areas in elderly nursing facilities. For the study, the activity areas of 44 facilities in Korea were investigated to categorize their spatial compositions and forms, and then a case study about 19 facilities was conducted to analyse their hierarchical characteristics. The results of the study were as follows: First, the major type of spatial composition among 44 research facilities was concentration, but compartment type was the main among unit-care facilities. By the year, all the types of spatial composition were evenly distributed during recent five years, while concentration type was about 40% before 2003. Second, the major form of activity areas was hall or corridor extension for large group. But there was more alcove or separation form among small group spaces. Third, in the case analysis about hierarchical characteristics, hall and corridor extension form met the requirements of accessibility and openness of public and semi-public areas. On the other hand, separation form had a problem in satisfying both requirements. The semi-private areas, which were around the elderly bedrooms and the elderly were able to watch activities in, were not sufficient in many facilities. Fourth, the division of public and semi-public area was mainly by furniture, and the individuality of semi-private area was defined by dead-end place and corner seats of the window or the corridor. The diversity of semi-private area was likely to be appeared in connection or distribution type. On the basis of the results, the basic design guidelines for activity areas in elderly nursing facilities could be suggested as follows: On the whole, connection or distribution type in spatial composition is more efficient for hierarchical flow than concentration or compartment type is, especially in Korean facilities having many elderly residents per floor. In detail, the design of public and semi-public area should be focused on their openness and accessibility. The recommended forms of activity areas were hall or corridor extension in public area, and living room, corridor extension, or large corridor in semi-public area to effectively function as large or small group spaces. In semi-private areas, the spatial diversity and individuality should be considered.