• 대한공간정보학회지
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• 제22권4호
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• pp.71-80
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• 2014

본 연구에서는 강원도를 대상으로 산사태로 인한 피해지역을 사전에 예측하였으며, 도로, 건물, 산림 등의 피해규모를 지자체별로 산정하였다. 산사태를 예측하기 위해서 기존의 연구 성과를 활용하여 산사태 취약성도, 발생가능성도, 위험지도 제작기법을 정립하였다. 도로, 건물, 산림의 산사태 피해규모는 누적강우량 100mm, 200mm, 300mm 발생시 각각의 산사태 위험지도를 제작하여 지자체별로 산정하였다. 그 결과 100mm~200mm 미만 누적강우량 발생시 도로피해는 홍천군, 건물피해는 정선군, 산림피해는 홍천군 순으로 나타났으며, 200mm~300mm 미만 누적강우량 발생시 도로피해는 춘천시, 건물피해는 평창군, 산림피해는 홍천군 순으로 나타났다. 특히, 300mm 이상 누적강우량 발생시 홍천군의 경우 도로, 건물, 산림피해가 다른 지자체에 비해서 가장 피해가 클 것으로 예측되었다. 이와 같이 지자체의 산사태 피해규모를 각각 산정함으로써 산사태 예방의 우선순위 결정뿐만 아니라 예산을 투입하는데 있어 의사결정의 기초자료가 될 수 있을 것으로 기대된다.

• Journal of Welding and Joining
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• 제26권3호
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• pp.67-73
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• 2008

Fatigue life evaluation of welded structures in a range of high cycles is one of the most difficult problems since extremely small plastic deformation and damage occur during the loading cycles. Moreover, it is very difficult to identify the strong non-linearities of welding, inducing residual stress. In this paper, numerical fatigue test method for welded structures was developed using continuum damage mechanics with inherent strain. Recently, continuum damage mechanics, which can simulate both crack initiation at the micro-scale level and crack propagation at the meso-scale level, has been adopted in the fracture related problem. In order to consider the residual stresses in the welded strictures, damage calculation in conjunction with welding, inducing inherent strain, was proposed. The numerical results obtained from the damage calculation were compared to experimental results.

• Structural Engineering and Mechanics
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• 제15권1호
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• pp.53-70
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• 2003

The motivation of this paper is to introduce the modern technology of large-scale cooling tower design. Thereby the innovative design concept for the world's largest cooling tower with a height of 200 m is briefly presented (Harte & Kr$\ddot{a}$tzig 2002, Bush et al. 2002). The new concept was considered not only for safety, but also for preservation of the durability of the structure, because cracking damage in large cooling towers in general cause extremely high cost of maintenance and repair. The paper demonstrates numerically the damage process in large cooling towers (Kr$\ddot{a}$tzig et al. 2001), and describes some basics of the numerical finite element approach for damage propagation modelling of shell structure. A prototype is analysed to trace the progressive damage process, whereby the changes in the dynamical behaviour of the structure, as mirrored in its natural frequencies and the corresponding mode shapes, are presented and discussed. Finally, the example shows that such damage processes develop progressively over the life-time of the shell structure.

• Earthquakes and Structures
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• 제7권5호
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• pp.609-626
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• 2014

The capabilities of a high-resolution Digital Image Correlation (DIC) system are presented within the context of deformation measurements of full-scale concrete columns tested under reversed cyclic loading. The system was developed to have very high-resolution such that material strains on the order of the cracking stain of concrete could be measured on the surface of full-scale structural members. The high-resolution DIC system allows the measurement of a wide range of deformations and strains that could only be inferred or assumed previously. The DIC system is able to resolve the full profiles of member curvatures, rotations, plasticity spread, shear deformations, and bar-slip induced rotations. The system allows for automatic and objective measurement of crack widths and other damage indices that are indicative of cumulated damage and required repair time and cost. DIC damage measures contrast prevailing proxy damage indices based on member force-deformation data and subjective damage measures obtained using visual inspection. Data derived from high-resolution DIC systems is shown to be of great use in advancing the state of behavioral knowledge, calibrating behavioral and analytical models, and improving simulation accuracy.

• 한국방재안전학회논문집
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• 제13권4호
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• pp.13-24
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• 2020

최근 급속한 경제발전과 온난화로 인해 이상기후 현상이 빈번하게 발생하고 있다. 자연재난의 유형 중 풍수해에 해당되는 호우, 태풍, 강풍, 풍랑, 대설 등은 대규모 인적·물적 피해를 발생시킨다. 피해를 최소화하기 위해서는 재난발생 전 피해규모를 예측하는 것이 중요하다. 본 연구는 풍수해의 재난유형 중 강풍피해를 중심으로 재난에 대비할 수 있는 강풍피해예측함수를 개발한다. 본 함수는 재해 연보의 강풍피해이력을 기반으로 기상요소와 지역적 특성을 반영하였으며, 기상정보를 실시간으로 수집할 수 있는 시스템에 탑재할 경우 단시간에 피해규모를 예측할 수 있다. 또한, 본 함수는 국가 혹은 지자체에서 수립하는 재난관리정책에 근거자료로 활용하여 강풍발생 시 피해를 최소화할 수 있다.

• 대한안전경영과학회지
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• 제12권1호
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• pp.35-42
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• 2010

Due to the industrialization and urbanization, the transport of hazardous materials increases, which rises possibilities in occurring prospective accidents in terms of hazardous material transport as well. This study applied the model developed from the previous research to analyze the scale of damage areas from the accidents related to hazardous material accidents, as well as suggested a method to measure automatically the scale of accident including casualties and environmental damage based on the guideline which suggests the quantities of hazardous materials exposed from an accident and was defined in the study of standardization for hazardous material classification. A buffering analysis technique of Geographic Information System (GIS) was applied for that. To apply the model which evaluates the scale of population and exposure to environment on each link, rail network, zones, rail accident data, rail freight trips, and locations of rivers etc were complied as a database for GIS analysis. In conclusion, a method to measure damage areas by the types of hazardous materials was introduced using a Clip and a Special Join technique for overlay analysis.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2007년도 정기 학술대회 논문집
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• pp.3-17
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• 2007

This paper provides an introduction to life-span simulation and numerical approach to support the performance design processes of reinforced concrete structures. An integrated computational system is proposed for life-span simulation of reinforced concrete. Conservation of moisture, carbon dioxide, oxygen, chloride, calcium and momentum is solved with hydration, carbonation, corrosion, ion dissolution. damage evolution and their thermodynamic/mechanical equilibrium. Coupled analysis of mass transport and damage mechanics associated with steel corrosion is presented for structural performance assessment of reinforced concrete. Multi-scale modeling of micro-pore formation and transport phenomena of moisture and ions are mutually linked for predicting the corrosion of reinforcement and volumetric changes. The interaction of crack propagation with corroded gel migration can also be simulated. Two finite element codes. multi-chemo physical simulation code (DuCOM) and nonlinear dynamic code of structural reinforced concrete (COM3) were combined together to form the integrated simulation system. This computational system was verified by the laboratory scale and large scale experiments of damaged reinforced concrete members under static loads, and has been applied to safety and serviceability assessment of existing structures. Based on the damage details predicted by the nonlinear finite element analytical system, the life-span-cost of RC structures including the original construction costs and the repairing costs for possible damage during the service life can be evaluated for design purpose.

• Journal of Information Technology Applications and Management
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• 제15권2호
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• pp.67-82
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• 2008

Risk that breed large size disaster is happening variously for cause at social. natural a management. Incidence and damage scale are trend that increase rapidly than past. In these circumstance, to keep operational continuity of organization, area, society, risk management action that establish systematic counter measure estimating and analyze occurrence possibility and expectation damage of risk is essential indispensable issue and the best countermeasure. Risk management action does by main purpose establish optimum disaster reduction countermeasure. To deduce various countermeasure, process that estimate and analyze occurrence possibility and expectation damage of risk is essential indispensable issue. Therefore, this paper studies process design that can presume risk occurrence frequency and damage scale through distribution of probability.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권2호
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• pp.786-799
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• 2021

Road damage detection is important for road maintenance. With the development of deep learning, more and more road damage detection methods have been proposed, such as Fast R-CNN, Faster R-CNN, Mask R-CNN and RetinaNet. However, because shallow and deep layers cannot be extracted at the same time, the existing methods do not perform well in detecting objects with fewer samples. In addition, these methods cannot obtain a highly accurate detecting bounding box. This paper presents a Multi-level Feature Pyramids method based on M2det. Because the feature layer has multi-scale and multi-level architecture, the feature layer containing more information and obvious features can be extracted. Moreover, an attention mechanism is used to improve the accuracy of local boundary boxes in the dataset. Experimental results show that the proposed method is better than the current state-of-the-art methods.

• 대한건축학회논문집:구조계
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• 제35권6호
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• pp.93-100
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• 2019

Modern society is transforming into an extreme climate environment. This is fatal to humans and ecosystems and is expected to cause large-scale damage. As this spokesman, natural disasters are increasing as this global average temperature rises. Social and economic damage by this tendency is also increasing. In addition, the frequency and scale of social disasters are increasing. Damage to the living area due to the damage of the infrastructure due to the increased reliance on infrastructure has been increasingly enlarged. In this research, various disasters such as natural disasters and social disasters analyze the impact on urban safety. A local autonomous entity K Priority Management Establish a kind of disaster, prepare crisis management manual, and use it as a basic material of education / training.