• Corrosion Science and Technology
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• 제6권6호
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• pp.269-274
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• 2007

The corrosion of steel in concrete is significant in marine environment. Salt damage is one of the most detrimental causes to concrete bridges and port structures. Especially, the splash and tidal zones around water line are comparatively important in terms of safety and life-time point of view. During the last several decades, cathodic protection (cp) has been commonly accepted as an effective technique for corrosion control in concrete structures. Zn-mesh sacrificial anode has been recently developed and started to apply to the bridge column cp in marine condition. The detailed parameters regarding Zn-mesh cp technique, however, have not well understood so far. This study is to investigate how much Zn-mesh cp influences along the concrete column at elevated temperature. About 100 cm column specimens with eight of 10 cm segment rebars have been used to measure the variation of cp potential with the distance from Zn-mesh anode at both $10^{\circ}C$ and $40^{\circ}C$ in natural seawater. The cp potential change and current diminishment along the column specimens have been discussed for the optimum design of cp by Zn-mesh sacrificial anode.

• Journal of the Korean Wood Science and Technology
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• 제39권6호
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• pp.531-537
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• 2011

본 연구는 지상부 사용조건에서 야외에 노출된 목재의 부후위험을 평가하기 위하여 수행되었다. 국내 72개 장소에서 10년 동안 축적된 기후자료를 활용하여 Scheffer 지수가 계산되었으며, 이에 근거하여 목재부후위험지도가 작성되었다. 제주, 서귀포, 광주, 전주 지역의 Scheffer 지수가 65 이상으로 부후위험이 높은 지역에 속하는 것으로 나타났으며, 이 지역을 제외한 나머지 지역은 Scheffer 지수가 35에서 65 사이의 값을 보여 부후위험이 중간 정도인 것으로 판명되었다. 그러나 기후조건에 따른 Scheffer 지수의 편차가 크기 때문에 부후위험이 중간정도로 판단된 지역이 기후변화에 따라 부후위험이 높은 지역으로 변할 수 있는 가능성이 높은 것으로 보인다. 특히 최근의 국내 기후가 아열대성으로 변화하는 경향을 고려할 때 국내 부후위험은 점차적으로 증가할 것으로 판단된다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.773-776
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• 2008

해양환경에서 철근 콘크리트의 부식은 매우 심하며, 염해는 콘크리트 교량과 항만 구조물의 부식을 일으키는 주요 요인 중 하나이다. 특히 비말대 및 간만대의 수면 부분은 구조물의 안전과 수명의 관점에서 볼 때 매우 중요하다. 지난 수십 년간 토목, 건축분야에서 콘크리트구조물 부식을 억제하기 위한 방식법 중 음극방식(cathodic protection, CP)은 많은 발전을 이룩하였으며 이제 보편화되는 추세에 있다. 최근 해양환경에서 콘크리트구조물의 음극방식을 위해 아연 메쉬 희생양극법이 개발 소개되었으나 아직까지도 이에 대한 구체적 내용이 잘 알려지지 않은 상태이다. 따라서 본 연구에서는 아연 메쉬 음극방식이 환경인자에 따라 콘크리트교각에 어떤 영향을 미치는지에 대하여 조사하였다. 아연 메쉬와 철근의 거리에 따라 음극방식 효과를 측정하기 위하여 약 100cm의 파일 시험편에 10cm 세그먼트 철근 8개를 설치하였으며, 아연 메쉬 희생양극에 의한 음극방식의 설계에 관련된 정보를 얻고자 파일 시험편의 높이에 따른 음극방식 전위의 변화와 전류의 감소치를 측정하였다.

• 한국지리정보학회지
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• 제24권1호
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• pp.112-125
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• 2021

해양공간계획은 해양을 체계적이고 합리적으로 관리하기 위해 9가지 용도구역으로 지정한다. 그 중 하나가 어업활동의 보호와 육성을 비롯한 수산물의 지속 가능한 생산을 위해 필요한 어업활동 보호구역이다. 본 연구는 V-Pass 자료를 활용하여 어업활동 지도를 제작하고 어업활동 밀집 공간을 도출함으로써 어업활동보호구역 지정에 필요한 요소 중 하나인 어업활동 공간을 정량적으로 파악하고자 한다. 이를 위해 V-Pass 자료를 정적 정보와 동적 정보가 결합된 데이터셋 구축, 어선 속도 계산, 어업활동 지점 추출, 비어업활동 공간 내의 자료 제거와 같은 전처리를 수행하였다. 최종적으로 선별된 V-Pass 점 자료를 이용하여 커널밀도추정으로 어업활동 지도를 제작하고 어업활동이 밀집된 공간을 분석하였다. 또한 어선의 업종과 계절에 따라 어업활동의 공간분포는 차이가 있음을 확인하였다. 본 연구를 통해 수행한 대용량 V-Pass 자료의 전처리 기법과 어업활동의 공간밀도 분석 방법은 향후 어업활동에 대한 공간특성평가 연구에 기여할 것으로 기대된다.

• Safety and Health at Work
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• 제9권3호
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• pp.352-355
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• 2018

Hazardous work zones (i.e., hot, warm, and cold) are typically established by emergency response teams during hazardous materials (HAZMAT) calls but less consistently for fire responses to segment personnel and response activities in the immediate geographic area around the fire. Despite national guidelines, studies have documented the inconsistent use of respiratory protective equipment by firefighters at the fire scene. In this case-series report, we describe warm zone gas levels using multigas detectors across five independent fire incident responses all occurring in a large South Florida fire department. Multigas detector data collected at each fire response indicate the presence of sustained levels of volatile organic compounds in the "warm zone" of each fire event. These cases suggest that firefighters should not only implement strategies for multigas detector use within the warm zone but also include respiratory protection to provide adequate safety from toxic exposures in the warm zone.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2011년도 학술발표회
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• pp.185-185
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• 2011

Mapping of artificial levee lines, one of major tasks in river zone mapping, is critical to prevention of river flood, protection of environments and eco systems in river zones. Thus, mapping of artificial levee lines is essential for management and development of river zones. Coastal mapping including river zone mapping has been historically carried out using surveying technologies. Photogrammetry, one of the surveying technologies, is recently used technology for national river zone mapping in Korea. Airborne laser scanning has been used in most advanced countries for coastal mapping due to its ability to penetrate shallow water and its high vertical accuracy. Due to these advantages, use of LiDAR data in coastal mapping is efficient for monitoring and predicting significant topographic change in river zones. This paper introduces a method for construction of a 3D artificial levee line using a set of LiDAR points that uses normal vectors. Multiple steps are involved in this method. First, a 2.5-dimensional Delaunay triangle mesh is generated based on three nearest-neighbor points in the LiDAR data. Second, a median filtering is applied to minimize noise. Third, edge selection algorithms are applied to extract break edges from a Delaunay triangle mesh using two normal vectors. In this research, two methods for edge selection algorithms using hypothesis testing are used to extract break edges. Fourth, intersection edges which are extracted using both methods at the same range are selected as the intersection edge group. Fifth, among intersection edge group, some linear feature edges which are not suitable to compose a levee line are removed as much as possible considering vertical distance, slope and connectivity of an edge. Sixth, with all line segments which are suitable to constitute a levee line, one river levee line segment is connected to another river levee line segment with the end points of both river levee line segments located nearest horizontally and vertically to each other. After linkage of all the river levee line segments, the initial river levee line is generated. Since the initial river levee line consists of the LiDAR points, the pattern of the initial river levee line is being zigzag along the river levee. Thus, for the last step, a algorithm for smoothing the initial river levee line is applied to fit the initial river levee line into the reference line, and the final 3D river levee line is constructed. After the algorithm is completed, the proposed algorithm is applied to construct the 3D river levee line in Zng-San levee nearby Ham-Ahn Bo in Nak-Dong river. Statistical results show that the constructed river levee line generated using a proposed method has high accuracy in comparison to the ground truth. This paper shows that use of LiDAR data for construction of the 3D river levee line for river zone mapping is useful and efficient; and, as a result, it can be replaced with ground surveying method for construction of the 3D river levee line.

• 한국조경학회지
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• 제35권2호통권121호
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• pp.71-80
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• 2007

Korea began preserving and managing natural monuments in 1933 under Japanese Colonization, but North Korea and South Korea were forced to establish separate natural monument management policies because of the division after the Korean Independence. The purpose of this study is to compare and analyze the natural monument management policies of both south and North Korea between 1933 and 2005 to introduce new policies for Korea unification. The following are the results: First, South Korea manages every type of cultural asset, including natural monuments, through the 'Cultural Heritage Protection Act,' whereas North Korea managing its cultural assets through the 'Cultural Relics Protection Act' and the 'Landmark/Natural Monument Protection Act.' Second, South Korea preserves and utilizes natural monuments for the purpose of promoting the cultural experience of Korean people and contributing to the development of world culture, whereas North Korea uses its natural monuments to promote the superiority of socialism and protect its ruling power. Third, North and South Korea have similar classification systems for animals, plants, and geology, but North Korea classifies geography as one of its natural monuments. Unlike South Korea, North Korea also designates imported animals and plants not only for the preservation and research of genetic resources, but also for their value as economic resources. Fourth, North Korea authorizes the Cabinet to designate and cancel natural monuments, whereas South Korea designates and cancels natural monuments by the Cultural Heritage Administration through the deliberation of a Cultural Heritage Committee. Both Koreas' central administrations establish policies and their local governments carry them out, while their management systems are quite different. In conclusion, it is important to establish specified laws for the conservation of natural heritages and clarified standards of designation in order to improve the preservation and management system and to sustain the diversity of natural preservation. Moreover it is also necessary to discover resources in various fields, designate protection zones, and preserve imported trees. By doing so, we shall improve South Korea's natural monument management policies and ultimately enhance national homogeneity in preparation for the reunification of the Koreas in the future.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.286_287
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• 2009

In this paper, the protectability of distance relay is furtherly researched. Based on the probabilistic modeling of the measurement errors, the protectability of three zones is presented in detail by considering their different protection aims denoted by sensitivity and selectivity. The optimal setting for the each zone can be obtained to provide a reference for the practical application.

• 한국지진공학회논문집
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• 제2권3호
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• pp.1-12
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• 1998

Korea is not considered to be one of the safe zones for earthquakes any more. According to the records of the historical records and recent earthquake events in Korea, the possibillty of disastrous seismic hazards cannot be ignored, Korea Earthquake Engineering Research Center (KEERC) and Earthquake Engineering Society of Korea(EESK) have been established by that consensus. In this paper, historical earthquake records and seismicity in Korea are reviewed. And the research activities and the research system for the earthquake hazards mitigation of KEERC are introduced and the efforts of ESSK to renovate seismic design code system and to optimize the protection levels against earthquake disasters is explained.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.25-32
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• 2005

In China, environmental noise policies are composed of correlated laws adopted by the Standing Committee of the National People's Congress and promulgated by the President of the country, regulations promulgated by the State Council and/or local government, standards issued by the Standardization Administration Committee (SAC) under the State Council. The laws mainly include the 'Environmental Protection Law' and the 'Law on Prevention and Control of Pollution From Environmental Noise' Regulations are often applied to a special noise pollution phenomenon of wide influence. They are generally only effective in a given area and/or a specific period. Tens of correlated standards specify the noise level limits of different functional zones of land use and of different equipment, machines, devices, appliances etc., and the measurement methods. In this presentation, a brief introduction to these policies and their operations is given and discussed. The conclusion is that the policies supply an effective legislative basis for environmental noise prevention and control in China, but still a lot of work should be conducted and completed to strive for a quiet society.