• International journal of steel structures
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• v.18 no.4
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• pp.1252-1264
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• 2018

Long span bridges such as steel cable stayed and suspension bridges are usually more flexible than short to medium span bridges and expected to have large deformations. Deflections due to live load for long span bridges are important since it controls the overall heights of the bridge for securing the clearance under the bridge and serviceability for securing the comfort of passengers or pedestrians. In case of sea-crossing bridges, the clearance of bridges is determined considering the height of the ship master from the surface of the water, the trim of the ship, the psychological free space, the tide height, and live load deflection. In the design of bridges, live load deflection is limited to a certain value to minimize the vibrations. However, there are not much studies that consider the live load deflection and its effects for long span bridges. The purpose of this study is to investigate the suitability of live load deflection limit and its actual effects on serviceability of bridges for steel cable-stayed and suspension bridges. Analytical study is performed to calculate the natural frequencies and deflections by design live load. Results are compared with various design limits and related studies by Barker et al. (2011) and Saadeghvaziri et al. (2012). Two long span bridges are selected for the case study, Yi Sun-Sin grand bridge (suspension bridge, main span length = 1545 m) and Young-Hung grand bridge (cable stayed bridge, main span length = 240 m). Long-term measured deflection data by GNSS system are collected from Yi Sun-Sin grand bridge and compared with the theoretical values. Probability of exceedance against various deflection limits are calculated from probability distribution of 10-min maximum deflection. The results of the study on the limitation of live load deflection are expected to be useful reference for the design, the proper planning and deflection review of the long span bridges around the world.

• Parasites, Hosts and Diseases
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• v.59 no.4
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• pp.415-419
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• 2021

The circumsporozoite protein (CSP) of Plasmodium spp. is a diagnostic antigen and useful biomarker for monitoring short-term/seasonal changes to malaria transmission. Using P. vivax CSP antibody ELISA, epidemiological characteristics were analyzed in the residents of Ganghwa, Cheorwon, Paju, and Goseong from 2017 to 2018. In Ganghwa and Cheorwon, 1.6% and 1.2% of residents, respectively, were PvCSP-antibody-positive in 2018, which indicates a decrease of 0.4% in the positive rate compared to 2017. The annual parasite incidence (API) in Ganghwa and Cheorwon was 24.9 and 10.5 in 2017 and 20.3 and 10.7 in 2018, respectively. Although the changes were not significant, the API in Ganghwa decreased slightly by 4.5 in 2018 compared to the previous year. In Paju and Goseong, 3.9% and 2.0% of residents were positive for the PvCSP antibody. The API in Paju was 13.1 in 2017 and 16.0 in 2018, although no malaria patients were reported for the 2 years. Therefore, the results suggest that PvCSP is a useful antigen for confirming initial malaria infection. Additionally, considering that the antibody is relatively transient, it can be employed for sero-epidemiological studies to determine the extent of malaria transmission in the current year.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.4 no.2
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• pp.86-94
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• 2023

Climate change is more rapid in the Arctic than elsewhere in the world, and increased precipitation and warming are expected cause changes in biogeochemical processes due to altered microbial communities and activities. It is crucial to investigate microbial responses to climate change to understand changes in carbon and nitrogen dynamics. We investigated the effects of increased temperature and precipitation on microbial biomass and community structure in dry tundra using two depths of soil samples (organic and mineral layers) under four treatments (control, warming, increased precipitation, and warming with increased precipitation) during the growing season (June-September) in Cambridge Bay, Canada (69°N, 105°W). A phospholipid fatty acid (PLFA) analysis method was applied to detect active microorganisms and distinguish major functional groups (e.g., fungi and bacteria) with different roles in organic matter decomposition. The soil layers featured different biomass and community structure; ratios of fungal/bacterial and gram-positive/-negative bacteria were higher in the mineral layer, possibly connected to low substrate quality. Increased temperature and precipitation had no effect in either layer, possibly due to the relatively short treatment period (seven years) or the ecosystem type. Mostly, sampling times did not affect PLFAs in the organic layer, but June mineral soil samples showed higher contents of total PLFAs and PLFA biomarkers for bacteria and fungi than those in other months. Despite the lack of response found in this investigation, long-term monitoring of these communities should be maintained because of the slow response times of vegetation and other parameters in high-Arctic ecosystems.

• Ecology and Resilient Infrastructure
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• v.4 no.1
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• pp.12-23
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• 2017

The Naeseong Stream is a meandering sand-bed stream flowing through mountains and has so long maintained its geomorphological uniqueness characterized by extensive braided bare bars. Recently, its long-lasting landscape has been changed due to encroachment of vegetation. In this study being a part of long-term monitoring research morphological changes of the 56.8 km long study reach of the Naeseong Stream, which occurred during the period of 2012 - 2016 were analyzed. Airborne LiDAR and terrestrial cross-section surveys were carried out. Hydrological and on-site investigation data were also collected. Among the main four sites, two bend reaches showed point bars enlarged, while along the other two straight reaches mid-channel bars were either newly formed or increased in area and height. At the highest deposition point of each bar, vertical changes which were caused by one or two times of sediment deposition amounted to 0.6 - 1.4 m. On the contrary channel bed degradation was not obvious. Overall morphological changes in the study reach were attributed to deposition of sediment which occurred during the flood in July 2016 on the bar surfaces vegetated during the precedent dry seasons. These kind of geomorphological processes are thought to be the same as those related to the existing mid-channel islands along the mid- and downstream reach of the Naeseong Stream.

• Korean Journal of Environment and Ecology
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• v.20 no.2
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• pp.235-258
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• 2006

The monitoring of vegetation and water quality before(2003), during(2004) and after(2005) the restoration work of Cheonggye Stream indicated that $BOD_5$ concentration before the project averaged 51.1mg/L and that both the inflow of water from Hang River and the funnel of subway station water into the stream lowered the $BOD_5$ to 3.3mg/L, improving its water quality to the third grade. Species of plants slightly increased from 121 to 132 after the restoration. Specifically, perennial plant comprised 35.6%, an increase from 24.8% recorded before the restoration. Phragmites communis and Zoysia japonica communities were observed as the introduction vegetation. However, Humulus japonicus and Erigeron canadensis communities, which were classified into the first grade according to the vegetation conservation classification, were found to be still prevailing though they were dominant community before the restoration, meaning that the ecological condition of plants had not changed very significantly. An the other hand the water quality of the reference reach was classified into the first grade based on $BOD_5$, which implies the water quality of the section was better than the project reaches. Besides the section had more diverse plant species which numbered 154, and furthermore, the rate of immigrated plants comprised 13% which was lower than 28.8% recorded by the project sections. The project reaches are considered to be inferior to the reference section in terms of ecological condition. The effectiveness of the stream restoration cannot be determined only by such short-term investigation as was conducted in this study, and it is considered that the effectiveness of the restoration of Cheonggye Stream can be determined only if investigations in other major factors are conducted over the long-term period.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.3
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• pp.75-87
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• 2018

The purpose of this study is to investigate conservation and management methods of the Joseon Royal Tombs under the Eastern District Management Office. Through the literature survey, we understood the process of change of Joseon royal tombs, and through field surveys and interviews, we understood the status of the interior and the surrounding area. In this process, topography, land use and flow of human traffic, architecture and stone objects, water system, historical forests, and facilities were set as the main evaluation indicators. Urbanization has damaged the original terrains of Royal Tombs as national roads, buildings and facilities have constructed in the inner and outer area of Joseon Royal Tombs. Construction of underground passage, land purchase, relocation and demolition of the buildings are required for the conservation of the Royal Tombs area, and then it is necessary to recover the original terrain. In the case of land use and pathways, there are many disconnection of the original ritual circulation, they should be maintained to remind the sacred atmosphere of the royal tomb. And It is necessary to collect accurate information on the lost buildings and stoneworks through literature survey and excavation investigation, and that investigations should be lead to the exposure or restoration of the ruins. Historical forests require periodic and ongoing monitoring and management, and it is necessary to establish new entrance area and appropriate facilities following the long-Term conservation and management plan. These plans should be classified into short, medium and long-Term projects according to urgency and securing financial resources with a long perspective to implement continuous and systematic projects.

• Korean Journal of Community Nutrition
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• v.14 no.6
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• pp.767-776
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• 2009

This study evaluated the effect of nutritional improvement of 0~5 year children of financially poor families after nutrition supplement of children and nutrition education in parents/guardians. The subject selected among applicants for low-income family financing of the government included 198 children (0~12 months:92, 1~5 years:106), and the average ages were 5.3 months and 2.4 years respectively. Food that includes each nutrient factor was provided to the subject for six months. Nutrition education was performed in two ways, through class and private education, once a month for both. Nutritional improvement was evaluated by body measurement and anemia prevalence rate. As to the survey on breast-feeding, complete breast-feeding accounted for 58.7%, weaning food 27.3%, and combined feeding 14.1% respectively, which shows that breast-feeding accounted for the largest percentage. The education program improved knowledge and attitude of the parents/guardians, which brings in positive effects on growth of children as well. The nutrition knowledge score was improved after nutrition education in 0~12 month children $(8.5\pm1.75\;to\;8.9\pm1.69)$ and 1~5 year children $(7.3\pm1.39\;to\;7.8\pm1.30)$. The nutrition attitude score was significantly improved in 0~12month children $(52.0\pm6.99$ to $53.5\pm5.21$, p < 0.001) and 1~5year children ($45.1\pm7.30$ to $49.0\pm5.96$, p < 0.001). In evaluation on nutritional improvement based on body measurements, it turned out that the wasting was reduced as for children in consideration of the height and weight according to the subject's age. The concentration of hemoglobin after the nutrient treatment for six months was significantly improved, and the anemia prevalence rate as well was reduced from 40.6% to 13.5%, which indicates the significant improvement. Based on the findings above, it turned out that providing quality food to children and nutrition education to the parents/guardians poorly fed in low-income families improved knowledge and attitude of the guardians and prevents anemia and improves growth, which brings in positive effects on growth of children. In the results regarding attitude and knowledge on nutrient/dietary life; however, the improvement level was relatively low when the extent before the education was too small, which indicates the need to revise and complement the contents and methods. In addition, as shown in the result of body measurement, long-term and consistent investigation is necessary since it is difficult to judge the effect on growth only based on short-term nutrient supplement.

• Journal of the Korean Institute of Gas
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• v.19 no.2
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• pp.54-65
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• 2015

China holding the world largest shale resources, has been trying to develop their domestic shale gas fields mainly with its NOCs. Chinese shale industry looks likely to have high potential to grow in the future, considering the eager support of Chinese government and the rapid development of relevant technologies by NOCs. However, there are opposite opinions as well that Chinese shale gas could not play a positive short-term results because of the complexity of structural geology, inadequacy of water resources and related infrastructure. Recently, Korean companies began to be interseted in Chinese shale gas industry, because of the special relationships with Korean industries in terms of geographic proximity and better opportunities due to the early phase of shale gas business in China. In this study, it was tried to help those companies looking out of future Chinese shale gas industry that surveying current status and problems of Chinese shale gas industry and relevant industries and investigating some trials and policies driven by China government. As a result, the various and long-term problems in Chinese shale development were reviewed and the active supports and polices of Chinese government, NOC's trials for establishments of their independent technologies and the cooperation with foreign companies or M&As were also investigated.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.32 no.1
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• pp.78-88
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• 2022

Objectives: To develop the smart sensor to protect worker's health from chemical exposure by adopting ICT (Information and Communications Technology) technologies. Methods: To develope real-time chemical exposure monitoring system, IoT (Internet of Things) sensor technology and regulations were reviewed. We developed and produced smart sensor. A smart sensor is a system consisting of a sensor unit, a communication unit, and a platform. To verify the performance of smart sensors, each sensor has been certified by the Korea Laboratory Accreditation Scheme (KOLAS). Results: Chemicals (TVOC; Total Volatile Organic Compounds, Cl₂: Chlorine, HF: Hydrogen fluoride and HCN: Hydrogen cyanide) were selected according to a priority logic (KOSHA Alert, acute poisoning statistics, literature review). Notifications were set according to OEL (occupational exposure limit). Sensors were selected based on OEL and the capabilities of the sensors. Communication is designed to use LTE (Long Term Evolution) and Wi-Fi at the same time for convenience. Electronic platform were applied to build this monitoring system. Conclusions: Real-time monitoring system for OEL of hazardous chemicals in workplace was developed. Smart sensor can detect chemicals to complement monitoring of traditional workplace environmental monitoring such as short term and peak exposure. Further research is needed to expand the scope of application, improve reliability, and systematically application.

• Journal of Korean Academy of Nursing
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• v.4 no.3
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• pp.63-79
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• 1974

1. The purpose of this study. The purpose of this study is to plan and investigate short-term nursing education of two-years associate degree program to produce middle-level professional nurses which are needed by-society and nation. Current nursing education in Korea is divided into four years degree program, three years diploma program Even (though) there are differences in the aims of their education, the curriculums are not much different between the education for producing leaders which is its basic purpose and training middle-level professional nurses. Therefore the purpose of associate degree program lies in minimizing the waste of time and finance which are invested for long-term education for middle-level professional nurses. And also this coincide with the policy of national technical training and definite supply of nurse manpower according to health policy for effective role and ability of nurse. 2. The method of study. This is based on the study of literature, research on the actual condition and investigation of opinion- through questionnaire. L) The study of literature: Domestic and foreign literatures for two years associate degree program were studied and investigated. 2) Research on the actual condition : Current three years nursing education program was collected and analysed. 3) Investigation of opinion. The problem of curried nursing education system and the possibility of two years associate degree program were investigated through questionnaire. 3. The result of the study. 1) The trend of recent nursing education. a. The aims of nursing in past chiefly taking care of physical disease of patient has recently changed to nursing of character including physical, mental, socio-economic, educational and psychological condition. b. For the performing systematic and effective nurse's duty according to her role, the-change of educational system which is classified as a range of education the period of education and certificate after graduation has been enforced or fulfilled. c. Nursing education also has a trend to become a collage or two years associate degree program which can get same legal protection as other educational institutions whose basic purpose is education. Attached nursing school to hospital is getting disappeared because of disadvantage of educational system. 2) Problems. Depending upon research on actual condition of current 3 years nursing education program. a. There are too many subjects. b. Contents of education could be doubled because major subjects are subdivided in detail. c. The credits for graduation are too heavy comparing to the period of study or the ability of students. (The necessary credits are 150.8 for three years according to actual investigation 4. There is no certain standard in organizing curriculum therefore there are too much differences between schools. 4. Basic Plan. The plan for two years associate degree program in nursing education depending on demand of professional nursing field of society is based on following items. 1) Training middle-level professional nurse lay emphasis on liberal arts and basic major field. 2) Liberal arts are divided into required and optional subjects and students could take courses by choice. 3) Major subjects are compound together by fields and they become the sciences of nursing Ⅰ,Ⅱ,Ⅲ,Ⅳ and every items has its educational purposes and contents major study includes laboratory practice and clinical experience. 4) The required credits for graduation are to which means 17-18 credits a semester. The above has been planned to solve the problems of current three years nursing education program. In conclusion for the achievement of this system, following items are needed. 1) It is necessary to change educational administration and system such as amendment of educational law or order of educational application of law. 2) Qualified professors should be available to understand and develope the idea or purpose of this educational system. 3) Local medical institutions should be opened widely and educational for clinical training. 4) The job after graduation should he secured positively.