• Journal of Korean Society for Geospatial Information Science
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• v.22 no.4
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• pp.31-38
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• 2014

Seismic of the Korean Peninsula is terrible about 1,900 times. Lately, because of a world-occurring seismic, investment of seismic design about ground & structures come to the force as means to protect national life and property. This study evaluated having seismic performance above design criteria among the existing port structures not applied seismic design. Based on the results, classified apprehensive area of liquefaction from seismic performance evaluation and made hazards according to liquefaction risk & structural performance using the analysis of seismic performance and GIS method. After Establishing quantitative & detailed input database through liquefaction evaluation and seismic performance, analysed all seismic data are used directly valuation data on repair reinforcement for apprehensive area of earthquakes.

• Safety and Health at Work
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• v.8 no.3
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• pp.237-245
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• 2017

Background: Solar furnaces are used worldwide to conduct experiments to demonstrate the feasibility of solar-chemical processes with the aid of concentrated sunlight, or to qualify high temperature-resistant components. In recent years, high-flux solar simulators (HFSSs) based on short-arc xenon lamps are more frequently used. The emitted spectrum is very similar to natural sunlight but with dangerous portions of ultraviolet light as well. Due to special benefits of solar simulators the increase of construction activity for HFSS can be observed worldwide. Hence, it is quite important to protect employees against serious injuries caused by ultraviolet radiation (UVR) in a range of 100 nm to 400 nm. Methods: The UV measurements were made at the German Aerospace Center (DLR), Cologne and Paul-Scherrer-Institute (PSI), Switzerland, during normal operations of the HFSS, with a high-precision UV-A/B radiometer using different experiment setups at different power levels. Thus, the measurement results represent UV emissions which are typical when operating a HFSS. Therefore, the biological effects on people exposed to UVR was investigated systematically to identify the existing hazard potential. Results: It should be noted that the permissible workplace exposure limits for UV emissions significantly exceeded after a few seconds. One critical value was strongly exceeded by a factor of 770. Conclusion: The prevention of emissions must first and foremost be carried out by structural measures. Furthermore, unambiguous protocols have to be defined and compliance must be monitored. For short-term activities in the hazard area, measures for the protection of eyes and skin must be taken.

• Architectural research
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• v.18 no.4
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• pp.129-136
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• 2016

People have experienced physical problems including vision problems with aging; some are normal and some are abnormal. When they have abnormal and impaired vision, they have a lower level of life satisfaction than their sighted peers. For the elderly with sight loss, well-designed housing could be an important indicator for their quality of life. Housing adjustment and modification could help the elderly cope with sight loss, do daily activities more independently, and lead to better quality of life. The purpose of this study is to investigate housing conditions for the elderly with vision impaired, state of housing adjustment or modifications, and the effects of housing conditions on the wellness of the elderly in Korea. For this study, 18 housing cases were investigated and a total number of 65 visually impaired people aged over 55 participated. Housing condition of those participated was poor. Most observed home hazards are level differences in living areas, obstacles in the hallway, confined space that is not allowed structural modification, swing doors from wardrobe or cabinets, color contrast, poor lightings, and etc. Majority of households participated in this study did not make modification or refurbishments, rather many of them tend to adapt themselves to their residential environments. Older adults living in better housing condition and under less difficult environments are likely to have higher life satisfaction. The effects of housing condition on wellness could be more influential when individual capabilities (e.g. health condition) are weaker. The findings underline that with intervention of individual characteristics, the effects of housing and physical environment on negative outcomes of vision loss would get ameliorated or reduced.

• Journal of the Korean association of regional geographers
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• v.18 no.4
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• pp.351-363
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• 2012

Although the Korean peninsula has been considered as a largely aseismic region compared with the surrounding high seismic areas such as North China and Japan, there are more than thirty Quaternary faults reported so far, which are mostly centered in the southeastern peninsula. Structural studies of active faults exposed in Yangnam-myeon of Gyeongju, SE Korea are largely interpreted to post date the late Quaternary, suggesting that the NE-trending reverse faults may result from the active stress regime in the peninsula. The prevailing present-day E-W $S_{Hmax}$ orientations in the peninsula are consistent with the nature of plate forcing stemming from the convergence between the Indo-Australian and Eurasian plates. It is clear that the Quaternary faults have been reactivated, although resolving more elaborate time intervals responsible for a future rupture remains a significant challenge. This study contributes to better assess many of potential seismic hazards in the study area, in particular, in terms of seismic stability for foundation of nuclear power plant.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.2
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• pp.107-115
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• 2015

As TBM construction method is widely applied to construct underground transmission lines, increasing attention has been drawn to SFRC(steel fiber reinforced concrete) segment with respect to structural characteristics. Health hazards of electromagnetic wave which the underground transmission lines emit has emerged, and there is a concern that electromagnetic wave can be amplified because a segment characteristic such as electrical conductivity is changed by steel fibers. In order to analyze correlation between steel fiber dosage and electromagnetic wave, the specimens were fabricated on three conditions to perform experimental tests. From the measured data, it is proven that there is no correlation between the electromagnetic wave and steel fiber reinforced concrete.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.2
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• pp.378-385
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• 2016

The internal circuit of the bus-bar for an electrical switch board is a prime cause of electric shock and short circuit accidents due to the exposure of live parts. Electrical fires can also be caused by animals and foreign substances in the switchboard that connect the components with a difficult structure resulting in overheating due to an increase in contact resistance. Preventing these types of accidents is a prime concern in the manufacturing process, such as cutting and bending. In this study, the cutting bus bar of a switch board contained improved modules as a flame retardant that isolates a separate blocks to prevent such problems. This was implemented as a scalable and flexible means of reducing electrical switchboard hazards to offer a safe switch board bus-bar structure of a new connecter type

• Economic and Environmental Geology
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• v.32 no.2
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• pp.177-187
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• 1999

Gravity, magnetic and VLF surveys were conducted to investigat the structural stability and hazards associated with the Ubong landfill in Pohang City, which has been built to dump industrial wastes. In 1994, the collapse of a bank happened in the 6th landfill site due to sudden heavy rain, and a large quantity of waste materials flowed out to the nearby landfill sites, factories and roads. We used $10{\times}10m$ resolution DEM data for gravity reductions. The maximum variation of the terrain effect in the survey area is about 0.5 mgal and the terrain effect is large in the vicinity of bank boundary. The Bouguer gravity anomaly map shows the effect due to the variatino of thickness and type of waste materials. The small negative gravity anomaly increases from the 9th site to the 6th site. The small negative gravity anomaly of the 9th site reflects the relatively shallow dumping depth of average 14.5 m in this site and increased density of waste materials by the repeated stabilization process of soil overlaying. The 6th site is located at the center of the former valley and rainfall and groundwater are expected to flow from south-east to north-west. Therefore, considering the previous accident of mixing waste and bank materials at the north-west boundary of the landfill, there may be some environmental problems of leakage of contaminated water and bank stability. The complex inversion technique using Simulated annealing and Marquardt-Levenberg methods was applied to calculate three-dimensional density distribution from gravity data. In the case of 6th site, it is apparent that the landfill had been dumped in four sectors. However, most part of the 9th site and showed that high magnetic industrial wastes were concentrated in the 6th site. The result of magnetic survey showing low magnetic anomalies along the boundaries of two sites is similar to that of gravity data. The VLF data also reveals four divided sectors in the 6th site, and overall anomaly trend indicates the directio of former valley.

• The Journal of Engineering Geology
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• v.24 no.1
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• pp.123-135
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• 2014

Earthquakes can cause serious loss of life and significant property damage. Thus, the study of active faults is important in evaluating future fault activity and hazards caused by future earthquake events. Structural mapping and the tracing of active faults are the primary steps in studies of active faults. Until now, active faults in South Korea have been mapped using aerial photography, satellite images, and low-quality DEMs. Lineament analysis as a means of identifying active faults is relatively difficult in Korea due to geological characteristics (weak tectonic activity) and dense vegetation cover. In this paper, we introduce the basic concept of the LiDAR technique (a new prospective remote sensing method) and a data analysis method that can overcome these problems. This paper will contribute to a better understanding of the airborne LiDAR technique and its application to South Korea. Some preliminary results from Korean and USA LiDAR data show the usefulness of this technique for tracing lineaments, active faults, and terraces in South Korea.

• Archives of Plastic Surgery
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• v.32 no.5
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• pp.567-572
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• 2005

An electrical burn used to result in the damage of the skin and underlying deep soft tissue injury. Thus, in order to preserve devitalizing tissues and promote the structural survival free flaps with ample blood supply are frequently employed. However, early unpredictable vascular injury and progressive tissue necrosis may cause the free flaps full of hazards. We applied 50 free flaps upon 41 acute electrical burn cases between 1998 and 2004. Injured areas, timing of operation and causes of flap loss were studied. The victim's ages ranged from 13 to 60 years. (an average 37.8 years) Thirteen out of 50 free flaps were lost totally: three cases were due to arterial insufficiency and ten venous congestion. Total loss of flaps were observed in 5 of 12 cases in the postoperative 3 weeks, 6 of 20 cases between 3 and 6 weeks and 2 of 18 cases after 6 weeks. In three of 12 cases the free flap was lost partially in the postoperative 3 weeks, 4 of 20 cases between 3 and 6 weeks and 1 of 18 cases after 6 weeks. The result was statistically significant by a T-test (p<0.05). This study showed that timing of the operation is accountable for the loss of free flap. It is most important to conduct the free flap procedure on an electrical injury at the time when the recipient vessel is definitely discernible and intact so as to minimize the loss of flap and spare the structures.

• Structural Engineering and Mechanics
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• v.68 no.6
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• pp.747-760
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• 2018

In the present study, a methodology for developing fragilities of arch concrete dams to assess their performance against seismic hazards is introduced. Firstly, the probability risk and fragility curves are presented, followed by implementation and representation of the way this method is used. Amirkabir arch concrete dam was subjected to non-linear dynamic analyses. A modified three dimensional rotating smeared crack model was used to take the nonlinear behavior of mass concrete into account. The proposed model considers major characteristics of mass concrete. These characteristics are pre-softening behavior, softening initiation criteria, fracture energy conservation, suitable damping mechanism and strain rate effect. In the present analysis, complete fluid-structure interaction is included to account for appropriate fluid compressibility and absorptive reservoir boundary conditions. In this study, the Amirkabir arch concrete dam is subjected to a set of 8 three-component earthquakes each scaled to 10 increasing intensity levels. Using proposed nonlinear smeared crack model, nonlinear analysis is performed where the structure is subjected to a large set of scaled and un-scaled ground motions and the maximum responses are extracted for each one and plotted. Based on the results, fragility curves were plotted according to various and possible damages indexes. Discrete damage probabilities were calculated using statistical methods for each considered performance level and incremental nonlinear analysis. Then, fragility curves were constructed based on the lognormal distribution assumption. Two damage indexes were introduced and compared to one another. The results indicate that the dam has a proper stability under earthquake conditions at MCE level. Moreover, displacement damages index is more conservative and impractical in the fragility analysis than tensional damage index.