• Journal of the Society of Disaster Information
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• v.15 no.3
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• pp.367-379
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• 2019

Purpose: This study aims to propose a framework for climate change risk management by analyzing characteristics of climate-induced disasters. Method: The recent global and domestic trends of loss and damage under natural disaster events and the characteristics of climate-induced disasters were analyzed to design a framework for climate change risk management. Results: In consideration of the uncertainty of climate risk and various spatio-temporal scales of climate disasters, a new framework is suggested for comprehensive climate risk management that includes risk assessment, goal setting, planning, monitoring and evaluation, learning and adjustment. The framework aims at an iterative process that is activated by stakeholder engagement. Conclusion: Pilot studies need to be conducted to revise and polish the framework in the future, and institutional arrangements should be prepared for the effective implementation of the comprehensive climate risk management.

• Earthquakes and Structures
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• v.23 no.6
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• pp.503-515
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• 2022

Global or partial damage to a structure due to the failure of gravity or lateral load-bearing elements is called progressive collapse. In the present study, the alternate load path (ALP) method introduced by GSA and UFC 4-023-03 guidelines is used to evaluate the progressive collapse in special steel moment-resisting frame (SMRF) buildings. It was assumed that the progressive collapse is due to the earthquake force and its effects after the removal of the elements still remain on the structures. Therefore, nonlinear dynamic time history analysis employing 7 earthquake records is used to investigate this phenomenon. Internal and external column removal scenarios are investigated and the stiffness of the connections is changed from semi-rigid to rigid. The results of the analysis performed in the OpenSees program show that the loss of the bearing capacity of an exterior column due to a seismic event and the occurrence of progressive collapse can increase the inter-story drift of the structure with semi-rigid connections by more than 50% and make the structure unable to satisfy the life safety performance level. Furthermore, connection stiffness severely affects the redistribution of forces and moments in the adjacent elements of the removed column.

• Journal of Korean Physical Therapy Science
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• v.29 no.3
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• pp.21-28
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• 2022

Background: Hamstring shortness results in the inappropriate activation of the quadriceps femoris because of the loss of the reciprocal inhibition mechanism. The purpose of this study was to investigate the effects of that activation during lunge exercises on the vastus medialis, vastus lateralis, medial, and lateral hamstrings in participants with hamstring shortness and normal length. Design: Quasi-experimental design Methods: Participants were divided into a hamstring shortness group(n=20) and a hamstring normal length group(n=23), based on a hamstring length test. During lunge exercises, muscle activation of the vastus lateralis, vastus medialis, medial, and lateral hamstrings were measured by electromyography. Results: Each muscle tested was less activated in the hamstring shortness group than in the hamstring normal length group. However, there was no statistically significant difference between the groups (p>.05). Conclusion: Although there was no significant difference between the shortness and normal hamstring groups during short lunge exercise time, longer exercising periods will result in the inappropriate activation of the quadriceps femoris. During lunge exercise, hamstring shortness causes an imbalance activation of quadriceps femoris and hamstring, and continuous hamstring shortness can cause damage on joints of lower limb.

• Steel and Composite Structures
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• v.47 no.4
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• pp.467-488
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• 2023

Seismic retrofit of an existing steel-reinforced concrete hospital building that features innovative use of a continuous energy-dissipative steel column (CEDC) system is presented in this paper. The special system has been adopted to provide an efficient solution taking into account the difficulties of applying traditional intervention techniques to minimize the impact on architectural functionality and avoid the loss of building function and evacuation during the retrofit implementation. The lateral stiffness and strength of the CEDC system were defined based on the geometric and mechanical properties of the steel strip dampers. The hysteretic behavior under cyclic loadings was defined using a simplified numerical model. Its effectiveness was validated by comparing the results of full-scale experimental data available from the literature. All the main design considerations of the retrofitting plan are described in detail. The effectiveness of the proposed retrofitting system was demonstrated by nonlinear time-history analyses under different sets of earthquake-strong ground motions. The analysis results show that the CEDC system is effective in controlling the deformation pattern and significantly reducing damage to the existing structure during major earthquakes.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.147-148
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• 2022

Due to recent climate abnormalities, the form of rainfall is changing to localized torrential rains. Localized torrential rains cause flooding in urban areas. In addition, in various industrial fields, there are cases where materials necessary for the process are kept outdoors, and damage from material loss and flooding of stockyards occurs during heavy rain. Accordingly, it is necessary to introduce a drainage layer where flooding is expected. This drainage layer places the aggregate inside and allows rainwater to penetrate and drain into the voids between the aggregates. However, the amount of voids differs according to the particle size distribution and particle size of the aggregate, and the drainage performance varies according to the compositional location of the aggregate. Therefore, in this study, the drainage characteristics according to the particle size, particle size, and compositional location of aggregates are analyzed using a fluid analysis program.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.1
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• pp.41-54
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• 2006

In case of leaving artificial slopes resulting from large-scale constructions, there may be secondary damage caused by soil loss due to erosion and collapse. Furthermore, slope-restoring constructions have a few problems such as monotonous landscape and difficult succession of secondary vegetation due to reckless use of exotic grass, despite attaining the initial purpose of revegetation. To settle this problem, selected plants deemed to be proper for revegetation were used on one of thin vegetation base methods, CODRA SYSTEM, and made seeding mixture experimental plots considering germination rates differing in each season. Native herbs, native shrubs and exotic herbs contents were increased by 30% and 50% respectively, centered on seeding quantity(30g/$m^2$) used as design standard in the seed spray method, in order to figure out proper quantity for revegetation in each season.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.5
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• pp.1-6
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• 2009

The temperature of exhaust gas was raised by increasing of engine movement on developing engine. Thermal of high temperature and pressure reverse in bellows, because of increasing of engine movement and the thermal performance of converter in combustion. As a result, thermal loss is increased and thermal efficiency is decreased rapidly in bellows, it can occur to damage in mechanical structure. In this study, it was necessary to analyze back pressure performance and thermal characteristic on driving condition in exhaust system. It was adapted braid type bellows and straight type exhaust pipe. It was compared with curve type exhaust pipe for lay-out on considering to design of exhaust system. It was necessary to improve thermal characteristic and back pressure performance so that expansion cavity pipe(ECP) was installed between bellows and catalyst convert. Not only decreasing back pressure was solved but also thermal characteristic problems in exhaust pipe because of increasing capacity. According to this study, the basis of data is presented when new exhaust system is designed.

• Journal of The Korean Society of Clinical Toxicology
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• v.1 no.1
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• pp.21-26
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• 2003

Methamphetamine (MA) is a major drug of abuse in Korea. Currently preliminary evidence suggests that MA dependence may cause long-term neural damage in human. Repeated exposure to psychostimulants such as methamphetamine results in behavioral sensitization, a paradigm thought to be relevant to drug craving and addiction in human. Sensitization alters neural circuitry involved in normal processes of incentrive, motivation, and reward. However the precise mechanism of this behavioral sensitization has not yet been fully elucidated. Repeated use of high dose MA causes neurotoxicity which is characterized by a long-lasting depletion of striatal dopamine (DA) and tyrosin hydroxylase activity of DA, DA-transporter binding sites in the striatum. The loss of DA transporters correlates with memory problems and lack of motor coordination. DA fuels motivation and pleasure, but it' s also crucial for learning and movement. This selective review provides a summary of studies that assess the neurobiological mechanisms of MA.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.21 no.9
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• pp.57-63
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• 2007

The occurrence of a corona is that electrical discharge due to the heterogeneity that occurs when an electrical field is concentrated in an electrode due to a cusp formed on said electrode. Wire treatment at the end of a 154[kV] dead end clamp for end users accelerates the occurrence of corona, which in turn leads to power loss and noise. In this study, the characteristics of the corona which occurs between porcelain insulators and support clamps of overhead lines used in 154[kV] power receiving facilities for end users were investigated. The corona, which cannot be identified by one common method, was measured utilizing a UV image camera. A risk assessment for fire damage and its status was suggested. The stress distribution of the electrical field by length of bare wire was suggested by means of the finite element method(FEMLAB). As a result, it was found to affect a porcelain insulators. These results can be utilized for the enhancement of clamp installation and safety in power facilities.

• Journal of Engineering Education Research
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• v.6 no.2
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• pp.15-21
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• 2003

The rapid development of mechanical civilization has brought us convenience in every aspects. But, on the other hands, it has also threatened us with the various industrial accidents. Such industrial accidents have given a big loss of many lives and property damage. People's awareness and concerns on the industrial accidents and safety have recently been increased. This study proposes a methodology to improve the safety education and training through the analysis of the recent industrial accidents. The research on workers' safety awareness and the status of safety education in industrial field was conducted in order to reduce the industrial accidents.