• Steel and Composite Structures
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• v.47 no.4
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• pp.451-454
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• 2023

Landslides are one of the natural disasters that cause a lot of financial and human losses every year It will be all over the world. China, especially. The Mainland China can be divided into 12 zones, including 4 high susceptibility zones, 7 medium susceptibility zones and 1 low susceptibility zone, according to landslide proneness. Climate and physiography are always at risk of landslides. The purpose of this research is to prepare a landslide hazard map using the Hierarchical Analysis Process method. In the GIS environment, it is in a part of China watershed. In order to prepare a landslide hazard map, first with Field studies, a distribution map of landslides in the area and then a map of factors affecting landslides were prepared. In the next stage, the factors are prioritized using expert opinion and hierarchical analysis process and nine factors including height, slope, slope direction, geological units, land use, distance from Waterway, distance from the road, distance from the fault and rainfall map were selected as effective factors. Then Landslide risk zoning in the region was done using the hierarchical analysis process model. The results showed that the three factors of geological units, distance from the road and slope are the most important have had an effect on the occurrence of landslides in the region, while the two factors of fault and rainfall have the least effect The landslide occurred in the region.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.9
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• pp.4319-4325
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• 2012

This study examines the effect of diverse land-use characteristics on the total sum of damages caused by natural hazards. The empirical results show that impermeable layer area, industrial land area, bare land area, stream area, and so on have a positive influence on damages, and that the area of levee has a strongly negative relationship with them. Therefore, this study strives to propose some efficient natural hazard mitigation ways in terms of land-use planning, based on our empirical findings.

• Proceedings of the KSRS Conference
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• v.1
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• pp.455-458
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• 2006

Stretching on the coastline of 70 km, the Tam Giang - Cau Hai Lagoon plays a very important role for the coastal ecology and socio-economic development of Hue region where was Vietnam's Ancient Kingdom Capital and recognized as a World's Cultural Heritage. Recently, coastal hazard in the lagoon have occurred seriously such as inlet movement and fill up, coastal erosion, flood and inundation, etc. These hazards have impacted on lagoon environment, resources, ecosystems, socio-economic and sustainable development of this coastal area. This paper present a case study using remote sensing data in combination with ground survey for monitoring the coastal hazards in Tam Giang - Cau Hai lagoon in recent decades. Analysis results find that during its natural evolution, the lagoon has been being in three situations of only one, two and three inlets. When inlets opened or displaced, coastal erosion have occurred seriously toward new balance condition. Flood and inundation occurs every rainy season in lowland plain around lagoon. The historical flood happened in early of November 1999 with six days long, created very terrible damages for Thua Thien Hue province. Remote sensing data with capability of regular update, large area coverage is effective provide real-time and continuous information for coastal hazards monitoring.

• Nuclear Engineering and Technology
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• v.52 no.8
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• pp.1771-1776
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• 2020

Adverse effects in the measured gamma spectrum caused by radioactive statistical fluctuations, gamma ray scattering, and electronic noise can be reduced by energy spectrum denoising. Wavelet threshold denoising can be used to perform multi-scale and multi-resolution analysis on noisy signals with small root mean square errors and high signal-to-noise ratios. However, in traditional wavelet threshold denoising methods, there are signal oscillations in hard threshold denoising and constant deviations in soft threshold denoising. An improved wavelet threshold calculation method and threshold processing function are proposed in this paper. The improved threshold calculation method takes into account the influence of the number of wavelet decomposition layers and reduces the deviation caused by the inaccuracy of the threshold. The improved threshold processing function can be continuously guided, which solves the discontinuity of the traditional hard threshold function, avoids the constant deviation caused by the traditional soft threshold method. The examples show that the proposed method can accurately denoise and preserves the characteristic signals well in the gamma energy spectrum.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.491-498
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• 2005

Acid Rock Drainage(ARD) is the product formed by the atmospheric(i.e. by water, oxygen and carbon dioxide) oxidation of the relatively common iron-sulphur minerals pyrite($FeS_2$). ARD causes the acidification and heavy metal contamination of water and soil and the reduction of slope stability. In this study the generation characteristics and the prediction of ARD of various road cut slopes were studied. An attempt to classify the rocks into several groups according to their acid generation potentials was made. Acid Base Accounting(ABA) tests, commonly used as a screening tool in ARD predictions, were performed. Sixteen rock samples were classified into PAF(potentially acid forming) group and four rock samples into NAF(non-acid forming) group. The chemical analysis of water samples strongly suggested that ARD with high content of heavy metals and low pH could pollute the ground water and/or stream water.

• Smart Structures and Systems
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• v.9 no.1
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• pp.1-20
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• 2012

In bridge engineering, maintenance strategies and thus budgetary demands are highly influenced by construction type and quality of design. Nowadays bridge owners and planners tend to include life-cycle cost analyses in their decision processes regarding the overall design trying to optimize structural reliability and durability within financial constraints. Smart permanent and short term monitoring can reduce the associated risk of new design concepts by observing the performance of structural components during prescribed time periods. The objectives of this paper are the discussion and analysis of influence line or influence field approaches in terms of (a) an efficient incorporation of monitoring information in the structural performance assessment, (b) an efficient characterization of performance indicators for the assessment of structures, (c) the ability of optimizing the positions of sensors of a monitoring system, and (d) the ability of checking the robustness of the monitoring systems applied to a structure. The proposed influence line- model correction approach has been applied to an integrative monitoring system that has been installed for the performance assessment of an existing three-span jointless bridge.

• Journal of Fisheries and Marine Sciences Education
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• v.24 no.2
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• pp.224-233
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• 2012

Hazard Analysis and Critical Control Points (HACCP) is a systematic preventative approach for food safety and is generally used in food industry to identify potential food safety hazards. Recently, the Korean Ministry for Food, Agriculture, Forestry and Fisheries planed to applicate HACCP programs as an effective approach to food safety and protecting public health at the aquaculture farm of rainbow trout, Oncorhynchus mykiss. For the purpose, it need to identify what kinds of hazards are in the aquaculture farm. In the present study, we established Sanitation Standard Operating Procedures (SSOP), which addresses sanitation conditions and practices in the aquaculture farm. SSOP is essential prerequisite programs of HACCP to reduce or eliminate the risk of the hazards being realized. We anticipate that the HACCP programs of aquaculture farm will contribute to supply foods in safety to consumers.

• Korean Journal of Occupational Health Nursing
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• v.29 no.1
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• pp.58-68
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• 2020

Purpose: Workers with chronic health problems find it difficult to maintain their work because of socioeconomic difficulties. The purpose of this study was to evaluate the relationships between physical, ergonomic, and mental health hazards in the workplace and chronic health problems of Korean workers. Methods: A total of 28,807 wage workers participated in the study and were selected using the Fifth Korean Working Conditions Survey (2017). Multiple logistic regression analysis was used to determine the associations between physical, ergonomic, and mental health hazards and chronic health problems. Results: Of the participants, 1,220 (4.23%) had chronic health problems. Even after adjusting the general characteristics, vibration, noise, high temperature, low temperature, dust, chemical and cigarette smoke, fatigue and painful posture, dragging or pushing or moving of heavy objects, repetitive hand or arm movements, working with a computer or smartphone, use of internet or e-mail, and anxiety situations increased the risk of chronic health problems. Conclusion: The study reaffirms that exposure of physical, ergonomic, and mental health hazards in the workplace significantly increases the risk of chronic health problems.

• Journal of the Korean Society of Safety
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• v.16 no.2
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• pp.57-62
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• 2001

In order to analyze the mechanism of semiconductor device damages by ESD, this paper adopts a new charged-device model(CDM), field-induced charged nudel(FCDM), simulator that is suitable for rapid routine testing of semiconductor devices and provides a fast and inexpensive test that faithfully represents ESD hazards in plants. The high voltage applied to the device under test is raised by the fie]d of non-contacting electrodes in the FCDM simulator. which avoids premature device stressing and permits a faster test cycle. Discharge current md time are measured and calculated The FCDM simulator places the device at a huh voltage without transferring charge to it, by using a non-contacting electrode. The only charge transfer in the FCMD simulator happens during the discharge. This paper examine the field charging mechanism, measure device thresholds, and analyze failure modes. The FCDM simulator provides a Int and inexpensive test that faithfully represents factory ESD hazards. The damaged devices obtained in the simulator are analyzed and evaluated by SEM Also the results in this paper can be used for to prevent semiconductor devices from ESD hazards.

• Korean Journal of Remote Sensing
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• v.21 no.1
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• pp.3-13
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• 2005

National Research Lab Project 'Optimal Data Fusion of Geophysical and Geodetic Measurements for Geological Hazards Monitoring and Prediction' supported by Korea Ministry of Science and Technology is briefly described. The research focused on the geohazard analysis with geophysical and geodetic instruments such as superconducting gravimeter, seismometer, magnetometer, GPS, and Synthetic Aperture Radar. The aim of the NRL research is to verify the causes of geological hazards through optimal fusion of various observational data in three phases: surface data fusion using geodetic measurements; subsurface data fusion using geophysical measurements; and, finally fusion of both geodetic and geophysical data. The NRL hosted a special session 'Geohazard Monitoring with Space and Geophysical Technology' during the International Symposium on Remote Sensing in 2004 to discuss the current topics, challenges and possible directions in the geohazard research. Here, we briefly describe the special session papers and their relationships to the theme of the special session. The fusion of satellite and ground geophysical and geodetic data gives us new insight on the monitoring and prediction of the geological hazard.