• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.881-881
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• 2012

낙동강유역에는 4대강 사업으로 8개의 보가 낙동강 본류에 새롭게 설치되었으며, 따라서 상류로부터 유입되는 유사가 보상류에 퇴적되어 하천제방이나 하천구조물의 안전을 위협할 수 있다. 또한 홍수시에는 농경지의 매몰과 저수지의 퇴적현상이 발생하는 등 유역유사에 의한 다양한 문제가 발생할 수 있으며, 강우로부터 유출되는 유사는 강우사상에 따라 빠르게 변할 수 있으나 수체에 즉각적인 영향을 유발하지 않을 경우 만성적인 특성으로 인해 침전물을 계속 이동시키며 축적되는 문제가 발생한다. 따라서 이러한 문제를 사전에 예측하고 낙동강유역에 대한 유역유사관리 대책마련을 마련하기 위해 유역유출과 유사의 이송 및 퇴적양상을 분석하여 유역관리를 위한 자료를 구축할 필요가 있다. 이러한 기초자료 분석을 위해 활용되는 유역모형 중 SWAT(Soil and Water Assessment Tool) 모형은 장기간 유역 유출로 인한 유사 모의를 수행하는데 가장 많이 활용되는 모형이며, 미국 농무성 농업연구소(USDA Agricultural Research Service, ARS)의 Jeff Amold 등에 의해 개발된 모형이다. SWAT 모형은 장기유출 및 유사 발생에 대한 시 공간적 변화를 모의하는 모형으로 넓은 범위의 유역에 대해 일단위 모의 간격으로 최대 100년까지 모의가 가능한 장기유역 모의에 최적화된 모형이다. 본 논문에서는 SWAT 모형을 이용하여 낙동강유역의 장기 유역 유출 및 유사 모의를 수행하기위해 2004년에서 2009년까지의 유출량 자료와 유량-유사량관계곡선 등을 이용하여 본류 및 지류 유출구 주요지점에 대해 검보정을 수행하고자 한다. 모의의 정확도 향상을 위해 안동댐, 임하댐, 영천댐, 합천댐, 남강댐, 밀양댐 및 낙동강 본류 등 총 7개 유역으로 구분하여 SWAT 모형을 구축하였으며, 각 유역별로 유출량과 유사량에 대하여 각각 보정 및 검증을 수행하였다. 낙동강 본류유역 총 7개의 댐 방류량자료와 20개의 대형하수종말처리장 방류량자료를 이용한 낙동강유역의 유출량 보정 및 검증 결과, 모의치가 실측치를 잘 반영하고 있는 것으로 나타났다. 또한 총 11개 지점의 수위관측소에 대해 유사량 측정 성과를 이용한 유사량 보정 및 검증 결과, 강우시 유사량 모의값은 유출량-유사량관계곡선 식을 잘 반영하였으나, 비강우시에는 모의값이 관계곡선 식의 결과값보다 대체적으로 높게 나타났다.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.3
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• pp.271-278
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• 2019

The corrosion of reinforcements embedded in concrete causes severe deterioration in reinforced concrete structures. As a countermeasure, epoxy coated reinforcements are used to prevent corrosion of reinforcements. When epoxy coated bars are used, the resistance of corrosion is excellent, but epoxy coating on the bars have a disadvantage of reduction in bond capacity comparing to that of normal bars. Therefore, it is necessary to confirm the bond performance of epoxy coated reinforcements through experimental and analytical methods. Bond behaviors of epoxy coated bars for various diameters of 13 and 19mm and thicknesses of cover concrete of 3 types(ratio of cover to bar diameter) are examined. As the diameters of the epoxy coated bars increase, the difference of bond strength between epoxy coated and uncoated bars also increases and damage patterns showed pull out failure. In addition, finite element analysis was performed based on the bond-slip relationship obtained by direct pullout test and compared with the flexural test results. It is considered that flexural member test is more useful than pullout test for simulating the behavior of actual structure.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.3
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• pp.209-218
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• 2011

The present study proposes a new estimation relationship for the transmission rate of the steel breakwater which is expected to make up for the weakness points in existing hard solution for shore protection. The steel breakwater consists of the wave dissipator of the dual horizontal plates, the supporting columns and their foundations, and thus its respective designs should also be conducted one by one. Furthermore, the breakwater has to ensure both functions of shore protection and structure stabilization. The study produced experimental data for the stability and safety investigation of the steel breakwater. The forces acting on the steel breakwater were classified into two categories, one is vertical up and down loads for the pile resistance and the other was maximum difference of the vertical load acting on horizontally different position for the torsion. The study applied the stability force produced by the summation of maximum pressure at each point and the safety force acting on each point simultaneously. The regular wave corresponding to the significant wave was utilized for measuring wave pressure and force. The study showed the method for the proper position of submerged upper plate by considering occurrence frequency of tide level. The design process finally determined by trial and error is proposed in the present study.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.6
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• pp.439-449
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• 2021

The recent reduction in greenhouse gases, interest in environmental pollution such as low-carbon emission policies is increasing. Accordingly, the penetration rate of eco-friendly vehicles, including hydrogen battery vehicles capable of reducing carbon emission, is increasing, and thus it is required for disaster prevention and safety-related measures. In this study, the degree of risk for the concentration distribution of hydrogen when leaking hydrogen fuel vehicles according to ventilation conditions was analyzed through numerical analysis, limited to places in parking lots. As a result, when only one hydrogen tank was released, the combustible volume ratio of hydrogen in the underground parking lot was up to 8.6%, and as ventilation continued, the volume ratio of combustible hydrogen decreased to less than 1% after 150 seconds, indicating that mechanical ventilation is essential. In the case of simultaneous release or stage release of three hydrogen tanks, the final combustible volume ratio of hydrogen is similar, but the increase in the combustible volume ratio of hydrogen in the early stage of release is low, and further research is expected.

• 한국노년학
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• v.38 no.1
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• pp.225-241
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• 2018

Self-driving is meaningful activity for older persons because it enlarges the range of activity and provides opportunities for social participation. Driving is a complex activity that requires integration of physical, cognitive and sensory functions and is influenced by human and psychological factors. Age related functional deterioration affects the driving ability of older drivers. The purpose of this study is to investigate the factors affecting the risk of accidents and driving cessation of elderly drivers through systematic literature review. MEDLINE, EMBASE, Cochrane Library, KoreaMed, Pubmed were used for searching articles published from 2007 to 2017. 'aged', 'aging', 'automobile driving', 'age factors' were used as search terms and 18 articles were finally selected for analysis among 1,458 articles. In result of the study, the most significant effect showed in the physical domain, the driving habit and the performance function. The most frequent used tools evaluated driving habit and the cognitive function. In demographic characteristics, there was a correlation with the driving discontinue according to sex and age. This study emphasizes the necessity of preparing measures for safety driving with elderly. In addition, it suggests the necessity of systematically services such as individual education programs based on various driving cessation related factors of the elderly.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.2
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• pp.12-28
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• 2019

Road geometry is one of the many factors that cause crashes, but the effect on traffic accident depends on weather conditions even under the same road geometry. This study identifies the variables affecting the crash severity by matching the highway accident data and weather data for 14 years from 2001 to 2014. A hierarchical ordered Logit model is used to reflect the effects of road geometry and weather condition interactions on crash severity, as well as the correlation between individual crashes in a region. Among the hierarchical models, we apply a random intercept model including interaction variables between road geometry and weather condition and a random coefficient model including regional weather characteristics as upper-level variables. As a result, it is confirmed that the effects of toll, ramp, downhill slope of 3% or more, and concrete barrier on the crash severity vary depending on weather conditions. It also shows that the combined effects of road geometry and weather conditions may not be linear depending on rainfall or snowfall levels. Finally, we suggest safety improvement measures based on the results of this study, which are expected to reduce the severity of traffic accidents in the future.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.6
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• pp.185-201
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• 2018

Road lighting is highly preferred as the major nighttime road safety countermeasures. When it comes to the pole-type road lighting, as it's installed at a certain height from the road surface, the driver is dazzled by the light source, interrupting the driver's visibility and furthermore, the light leaks to the area outside the road boundary, worsening the energy efficiency as well as generating the light pollution to the surrounding environment including the animals and plants. The study developed the low-level lighting systems, so it is possible to prevent the lights from being strayed, so there is no any side effects in terms of the sleep deprivation. The study compared the performance as the lightings between low-level lightings and conventional pole based lighting systems. As the results, the low-level lighting systems showed the higher performance in terms of average surface luminance, uniformity, glare compared to the conventional lighting systems.

• Journal of Navigation and Port Research
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• v.43 no.3
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• pp.209-218
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• 2019

Coastal cities suffer a great deal of storm and wind damage. The storm and wind characteristics vary between cities. Therefore, a storm and wind damage management system suited for specific characteristics is required for each coastal city. In this study, we analyze the current situation and establish the problem of storm and wind damage management system in regards to urban management, coastal management and disaster management. We also review the storm and wind damage management system for the USA and Japan. We consequently propose a plan to improve the storm and wind damage management system. As a result of the study, in terms of city management, we recommend the compulsory identification of disaster prevention districts, implementation of the integrated coastal city management plan, designation of natural disaster risk mitigation area as disaster prevention district, the division of disaster prevention district into wind damage prevention district, storm damage prevention district, erosion damage prevention district, the building of restrictions at the disaster prevention district by ordinance, etc. In regards to coastal management, we suggest the delegation of authority to delegate coastal erosion management area to the local government, the subdivision of coastal erosion management area into erosion serious area, erosion progress area, erosion concern area, the building restrictions at coastal erosion management area by ordinance, development of erosion prediction chart, etc. In relation to disaster management, we recommend the integration of "countermeasures against natural disasters act" and "disasters and safety management basic act", the local government-led disaster prevention system, the local disaster management network, and the customized local disaster prevention plan, etc.

• Journal of the Society of Disaster Information
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• v.15 no.1
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• pp.1-11
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• 2019

Purpose: This study intends to determine how disaster prevention characteristics of important state-designated wooden cultural properties in Gyeongsangnam-do vary according to the surrounding environments and to examine disaster prevention measures for wooden cultural properties that fit their surrounding environments accordingly. Method: The designation status and characteristics of cultural properties in Gyeongsangnam-do and Gyeongsangbuk-do were identified, and the damage status of cultural properties in Gyeongsangnam-do and Gyeongsangbuk-do was reviewed based on the history of disasters. Also, the disaster prevention environments for 58 state-designated wooden cultural properties in Gyeongsangnam-do and Gyeongsangbuk-do were analyzed separately into mountainous area, rural area and urban area, topographic characteristics were drawn. Results: For cultural properties located in urban areas, it was found that security guards were arranged properly and disaster prevention training was carried out well. In addition, access condition to the cultural properties was adequate; prompt access to such properties was possible. In rural areas, flame retardant works have been undertaken properly and many cultural properties were found to be located on a flat ground. Mountainous areas had highly inadequate access condition to cultural properties and disasters occurred most frequently in these areas in the past. Conclution: First, for wooden cultural properties located in urban areas, it is necessary to secure the self-defense fire service manpower for an initial response and reinforce the disaster prevention education. Second, for wooden cultural properties located in rural areas, prevention projects such as insect control project and disaster prevention insurance should be carried out in order to protect the cultural properties. Third, as for wooden cultural properties located in mountainous areas, it is necessary to prepare establish to reinforce self-response capability.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.523-531
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• 2018

The purpose of this paper is to derive priorities and implications for the organic resource conservation policy in the livestock sector. We conducted a survey on the importance-performance of the organic waste resource reclamation of livestock sector using a 5-point Likert scale. The importance average for the resource recycling of livestock organic waste was 3.63 and the average of performance was 3.04. As a result of the IPA on livestock manure recycling measures, it is necessary to improve feed quality, establish a local recycling system, increase demand for compost and liquid, enhance customer linkages, and develop cost reduction technologies. It requires intensive support for promoting the spread of odor reduction technologies and integrated management of biomass. It is necessary to introduce mid- and long-term measures such as the revival of feed in tariff, promote by-product feeding, establish solid fuel process management standards, create hygiene safety standards, develop eco-beads and promotion of feed conversion. It is required to strengthen support for the development of odor reduction technologies and prepare consultative organizations among related departments, develop eco-friendly solid fuel technology, and support policies for renewable energy certification.