• Korean Journal of Agricultural Science
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• v.45 no.3
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• pp.521-532
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• 2018

In recent decades, the dry stream phenomena of small and medium sized rivers have been attracting much attention as an important social problem. To prevent dry stream phenomena, it is necessary to build an infrastructure that manages rivers. To accurately determine the progress of dry stream phenomena, it is necessary to continuously measure the discharge and other hydrological factors for small and medium sized rivers. However, until now, the flow data for small and medium rivers in Korea has been insufficient. To overcome the lack of supporting data for supporting rational decision-making in policy and project implementation, a short- and long-term hydrological model was developed that takes into consideration hydrological changes such as the increase of the impervious area due to urban development and groundwater pumping, the construction of a large-scale sewage treatment plant, the maintenance of stream-oriented rivers, etc. In the developed model, the distributed grid is represented by three layers: Surface flow, interflow, and groundwater flow. The surface flow and intermediate flow flowed along the flow direction, and the groundwater flow was calculated by a two-dimensional groundwater analysis model such that the outflow occurred in all directions without a specific flow direction. The effects of land use and cover on evapotranspiration and infiltration and the effects of multiple landscapes can be simulated in the developed model.

• KEPCO Journal on Electric Power and Energy
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• v.3 no.1
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• pp.23-28
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• 2017

The life management technology becomes important as the failure risk of the aged power transformers increases. Asset management technology, therefore, has been developed to evaluate the remaining life and build replacement strategies of power transformers, which enables an optimal investment decisions based on reliability and economic feasibility. The remaining life assessment technology uses data related to such as installation, operation, maintenance, refurbishment, and disposed history of power transformers. The optimal investment decision additionally uses data related to failure and social costs. To develop the asset management technology in power transformers, it is important to find deterioration parameters directly indicating degradation of power transformers. In this study, 110,000 DGA data during the past 35 years have been analyzed in order to find the deterioration parameters related to the degradation of power transformers. The alarm rates of combustible gases ($H_2$, $C_2H_2$, $C_2H_4$, $CH_4$, $C_2H_6$), TCG CO, and $CO_2$ were analyzed as deterioration parameters. The origin of the gas was discussed in connection with discharge, overheating and insulation aging.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.9
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• pp.1571-1576
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• 2016

A Tesla coil is an electrical resonant transformer circuit invented by Nikola Tesla in 1891. It is used to produce high-voltage, low-current, high frequency alternating-current electricity. Tesla coil can generate a long streamer with several million volts of electricity as a high voltage device. It is basically consists of a voltage transformer, high voltage capacitor, spark gap, primary coil, secondary coil and toroid. It is difficult to appear in the output size of the streamer is controlled by the spark gap. The general decision method of the length of streamer is to display the electric output in accordance with the design specifications in initial development plan. Design specifications and the electric output is determined by the application of facilities. In this paper the spark gap is replaced with periodic switching semiconductor device to control output voltage easily in order to apply overvoltage protective circuit due to a secondary coil and a performance test. In these days, their main use is for entertainment and educational displays of the museum, although small coils are still used as leak detectors for high vacuum systems.

• Korean Journal of Artificial Intelligence
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• v.8 no.1
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• pp.7-9
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• 2020

In this paper, a study was conducted to find a self-diagnosis method to prevent the spread of COVID-19 based on machine learning. COVID-19 is an infectious disease caused by a newly discovered coronavirus. According to WHO(World Health Organization)'s situation report published on May 18th, 2020, COVID-19 has already affected 4,600,000 cases and 310,000 deaths globally and still increasing. The most severe problem of COVID-19 virus is that it spreads primarily through droplets of saliva or discharge from the nose when an infected person coughs or sneezes, which occurs in everyday life. And also, at this time, there are no specific vaccines or treatments for COVID-19. Because of the secure diffusion method and the absence of a vaccine, it is essential to self-diagnose or do a self-diagnosis questionnaire whenever possible. But self-diagnosing has too many questions, and ambiguous standards also take time. Therefore, in this study, using SVM(Support Vector Machine), Decision Tree and correlation analysis found two vital factors to predict the infection of the COVID-19 virus with an accuracy of 80%. Applying the result proposed in this paper, people can self-diagnose quickly to prevent COVID-19 and further prevent the spread of COVID-19.

• Women's Health Nursing
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• v.12 no.2
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• pp.87-96
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• 2006

Purpose: This study was conducted to provide fundamental information for a system establishment of advanced practice nursing for gynecological cancer patients (APN-GCP). Method: Data was collected by focus group and individual interviews and analyzed in the framework of the Grounded theory method mapped by Strauss and Corbin (1990). There were 13 subjects in this study (nurses, doctors, patient and her family). Result: We identified 87 concepts, 22 sub-categories, and 10 categories. Categories for role expectation were arrangement of diagnosis and treatment process, giving information of treatment course, support of treatment process, patients' right toward making a decision of treatment, counseling and teaching after discharge from hospital, medical insurance and financial problems, counseling about sexual problems and use of family and community resources. All subjects perceived the necessity of an APN-GCP. An APN-GCP requires over 2$\sim$7 years clinical experience and a master's degree. Services would be performed from initial registration to termination of treatment or death, and accomplished on an outpatient clinic basis. Conclusion: The nursing delivery system and curriculum should be developed for a women's health nurse practitioner including APN-GCP. As a further step, cost-effectiveness and projected estimation of manpower of APN-GCP should be studied in the future.

• Journal of Korean Society of Rural Planning
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• v.21 no.3
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• pp.101-112
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• 2015

The objective of this study was to investigate non-point sources (NPS) pollution and prioritize management areas affected by NPS pollution in the Saemangeum Watershed. AHP (Analytical Hierarchy Process) technique was selected to prioritize sub-watersheds for effectively managing NPS pollution in this study areas. Generation properties of NPS pollution, discharge properties of NPS pollution, and runoff properties of NPS pollution were selected and set for AHP. Weighted descriptors including indicators like numbers of livestock, land- and livestock-system loads, rainfall, and impervious area ratio were generalized from 0 to 1 and multiply each index based on screened 17 survey data. The results were visualized as maps which enable resource managers to identify sub-watersheds for effective improving water quality. The sub-watersheds located in Gongdeok-Myeon, Yongji-Myeon, Hwangsan-Myeon of Gimje-Si were selected for managing NPS pollution control areas. This result presented that these sub-watershed are more affected by the pollution from livestock-system than from land-system. The finding from this study can be used to screen sub-watersheds that need further assessment by managers and decision-makers within the study area.

• Journal of Hospice and Palliative Care
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• v.11 no.2
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• pp.106-110
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• 2008

Palliative sedation has been used in patients who undergo intractable suffering at the end of life. Its implementation, however, may be complicated due to resistance of clinicians and barrier of bioethical issues. Here, we present 50-year-old man with stomach cancer and multiple bone metastasis who was treated with palliative chemotherapy and radiotherapy. He suffered from refractory pain on the whole body even after standard analgesics and multidisplinary effort to relieve. Upon shared decision for sedation, he was given midazolam until discharge. Literature reviews reveal cases similar to the present case.

• 유체기계공업학회:학술대회논문집
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• 2005.12a
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• pp.613-616
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• 2005

In general, the hollow jet valve, the fixed cone valve had been used for the urgency released or maintenance of the flow rate. Nowadays, the butterfly valve, the gate valve are applied in economic performance and operation maintenance more than the hollow jet valve, the fixed cone valve. However, in the case of butterfly valve, it should be required the strict application standard to the cavitation coefficient because the structural axis and disk were situated in pipe channel and the occurring the shock problem by Karman Vortex. And, the judgment data for choice were slight lowdown in water supply and drainage facilities standard or Japanese penstock technology standard, various standard of KOWACO etc. Therefore. there were investigated the valve inside phenomenon (cavitation, disk chattering, vibration) by velocity of flow and the stability examination of body by high velocity of flow through flow scale model test using the numerical analysis and PIV to establish the applicable extensibility of the butterfly valve for the urgency released valve.

• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.1023-1026
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• 2004

우리나라는 토지이용이 고도화 되어 있고 상수원에 각종 오염시설이 이미 입지해 있으며 개발압력이 가중되고 있는 현실을 고려해 볼 때 환경기초시설 확충 및 배출기준 강화 등 사후적 관리방법으로는 상수원의 수질개선에 한계가 있다. 그리고 상수원수질보전을 위한 기존의 토지이용 규제정책도 일정 규모 이하는 규제 대상에서 제외되어 소규모 시설에 대한 효율적 규제가 안 되고 있을 뿐만 아니라, 토지이용 규제에 의한 주민의 재산권 제한으로 민원도 계속되고 있다. 따라서 오염원의 총량적인 증가에 효율적으로 대처하고 주민이 스스로 오염원 총량발생을 억제함과 동시에 환경친화적으로 지역을 개발할 수 있는 새로운 수질관리 기법이 도입될 필요가 있다. 이에 본 연구에서는 섬진강을 대상하천으로 각 배수구역별 유황분석을 실시하고, 오염원조사, 부하량 산정, 수질모델링의 불확실성등 안전율을 고려하여, 오염원 총량관리 기본방침을 기준으로 오염총량관리대상 오염물질의 종류인 생물학적 산소요구량(BOD)에 대하여 2006년과 2011년의 장래수질예측을 실시하였고 그 결과 목표수질을 달성할 수 있는 배수구역별 부하량을 할당하였다.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2010.04a
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• pp.389-393
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• 2010

The Objective of this study was to develop a system for visualizing inundation area by using 1-D numerical model analyzing damage information such as inundation area, facilities, land usages, population, building, loads. In this study, we have reviewed hydraulic models to select a flood model for simulation of discharges, water depths and velocities. The study area is Namhan River from Youngwol to Paldang Dam which had a flood damage on upper and below regions of Chungju Dam by a storm event in 2006. At the first, we developed the DB system base on GIS thematic map, ortho images, cadastral maps to analyze flood damages and support decisions making. Changing the boundary conditions such as discharge at the gauging stations, flood simulations were performed and then damages were extracted from the databases information support system based on 1-D numerical hydraulic model, it is expected to be able to analyze flood damages and support a decision making for reduce flood relate damages. In the future, the system developed in this study could be applied for flood forecasting system of small scaled streams.