• Journal of the Korean earth science society
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• v.26 no.8
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• pp.809-820
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• 2005

The fluvial sequence developed along the channel margin of meander bends in the midstream of the Yeongsan River consists of channel deposits at the bottom and overbank deposits at the top, and shows a fining-upward trend. The fluvial deposits consist of 7 sedimentary facies, and facies association forms 7 architectural elements. The channel deposits formed as channel bar or point bar. The channel bar deposits consisted of architectural element of gravel bedform were formed by channel lag deposits within the channel; whereas, the channel bar deposits consisted of architectural elements of downcurrent-dipping inclined strata sets, cross-stratified and horizontally stratified sets, and horizontally stratified sets were formed by downstream migration of sand wave or downstream transport of sand by traction current in the upper flow regime conditions within the channel. The point bar deposits consist of architectural elements of down current-dipping inclined strata sets, horizontally stratified sets, cross-stratified and horizontally stratified sets, and laterally inclined and horizontally stratified sets. These architectural elements are thought to have been formed by the combined effects of the migration of sand dunes and the formation of horizontal lamination in the upper flow regime plane bed conditions. The overbank deposits consist of the architectural elements of overbank fine and sand sheet and lens. The overbank fines were formed by settling of mud from slackwater during flooding over floodplain whereas the sand sheet and lens were formed by traction of sands introduced episodically fiom channel to the overbank during flooding.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.2C
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• pp.59-69
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• 2009

Based on the data obtained from field investigation and soil testing to slope hazards occurrence section and non-occurrence section in crystalline rocks like gneiss, granite, and so on, a prediction model was developed by the use of a decision tree model. The classification standard of the selected prediction model is composed of the slope angle, the coefficient of permeability and the void ratio in the order. The computer program, SHAPP ver. 1.0 for prediction of slope hazards around an important national facilities using GIS technique and the developed model. To prove the developed prediction model and the computer program, the field data surveyed from Jumunjin, Gangneung city were compared with the prediction result in the same site. As the result of comparison, the real occurrence location of slope hazards was similar to the predicted section. Through the continuous study, the accuracy about prediction result of slope hazards will be upgraded and the computer program will be commonly used in practical.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.3
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• pp.317-331
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• 2023

Objectives: Construction workers are exposed to various hazardous substances simultaneously. However, little is known about the exposure hazards in construction industry. This study was aimed at identifying the risk of exposure hazards among construction workers. Methods: The expert survey (n=29) was conducted, including construction industry health managers (n=11) and work environment monitoring experts (n=18), on exposure probability, intensity and risk of hazardous substances by construction occupations Results: The exposure hazards of 30 construction occupations were identified and summarized through a literature review and expert survey. The most prevalent hazards were in order of noise, awkward posture, heat/cold, crystalline silica, cement/concrete dust, metal fumes, and volatile organic compounds. The hazards with highest risk score(over seven points) at construction occupations were noise(formwork carpenter, concrete finisher, rebar worker, demolition worker, driller/rock blaster), hazardous rays(welder), heat/cold (earthworks, formwork carpenter, rebar worker, concrete placer, scaffolder), awkward posture(bricklayer, caulker/tile setter, rebar worker) and heavy lifting(bricklayer, rebar worker). Among construction workers, the job types with the highest risk of exposure to carcinogens, and in which occupational cancer has been reported, were in order of stonemason, concrete finisher, rock blaster, welder, insulation installer, painter, scaffolder, plant worker and earthworks in order Conclusions: Systematic research and discussion on occupational disease among construction workers and its various hazardous factors are needed to establish job exposure matrix for facilitating standard for promptly processing the workers' compensation.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.3
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• pp.184-195
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• 2013

Objectives: The purpose of this study is to provide information in reference to the health hazards of asbestos substitutes. Methods: This study was conducted by reviewing the literature on the types of asbestos substitutes, product development using alternative materials and the health effects associated with asbestos substitutes. Results: Synthetic or natural fibers such as synthetic vitreous fiber, polyamide, attapulgite, sepiolite and wollastonite are known as asbestos substitutes. According to the patents data of the United States and Europe since the 1970s, many asbestos-free products have been developed in a variety of industries. Health hazards of some asbestos substitutes including synthetic vitreous fibers have been evaluated by many experts, however, additional researches are required to be carried out in the future. Conclusions: Alternatives to asbestos are necessary to develop the asbestos-free products. Health hazards for only several asbestos substitutes have been assessed so far and occupational exposure limit has not been established for many asbestos substitutes yet. Therefore, even though workers are handling asbestos-free products, it is recommended to control the working environment well enough in order to minimize the exposure of workers to dusts or fibers caused during the working process.

• The Journal of Engineering Geology
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• v.23 no.3
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• pp.305-314
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• 2013

Recent international and national research trends in landslide hazards were analyzed by performing a literature search of relevant scientific journals. For obtaining data from Korea, we used 'Information for Environmental Geology' (IEG), which covers 17 journals in the field of environmental geology. A total of 54 articles related to landslide hazards were found in 5 journals published in the period 2000-2012. The most common topic was landslide prediction or susceptibility (29 articles), followed by landslide mechanisms. For international information, we analyzed 1,851 articles from the 'Web Of Science' published from 2003 to the present. Researchers in Italy have published the greatest number of papers in this field, while papers from Korea rank first in terms of the citation index.

• Journal of Biosystems Engineering
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• v.27 no.5
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• pp.391-398
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• 2002

During handling unitized products, they are subjected to a variety of environmental hazards. Shock and vibration hazards are generally considered the most damaging of the environmental hazards on a product and it may encounter while passing through the distribution environment. A major cause of shock damage to products is drops during manual handling. The increasing use of unitization of pallets has been resulted in a reduction of the shock hazards. This has caused an increasing interest in research focused on vibration caused dam age. Damage to the product by the vibration most often occurs when a product or a product component has a natural frequency that falls within the range of the forcing frequencies of the particular mode of transportation being used. Transportation vibration is also a major cause of fruit and vegetable quality loss due to mechanical damage. This study was conducted to determine the vibration characteristics of the corrugated fiberboard bones for packages of pears, and to investigate the degree of vibration injury of the pears in the boxes during the simulated transportation environment. The vibration tests were performed on an electrohydraulic vibration exciter. The input acceleration to exciter was fixed at 0.25 G for a single container resonance test and 0.5 G for the vertical stacked container over the frequency range from 3 to 100 Hz. Function generator (HP-33120A) was connected by wire to the vibration exciter for controlling the input acceleration at a continuous logarithmic sweep rate of 1.0 octave per min. The peak frequency and acceleration on the single box test were 22.02 Hz, 1.5425 G respectively, and these values on the vertical stacked boxes were observed from the bottom box 19.02, 18.14, 16.62 and 15.40 Hz and 2.2987, 3.7654. 5.6087, and 7.9582 G, respectively. The pear in the bottom box had a slightly higher damage level than the fruit packed in the other stacked boxes. It is desirable that the package and transportation system has to be so designed that 15∼20 Hz frequency will not occur during the transportation environment.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.11 no.1
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• pp.17-24
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• 2005

During handling unitized products, they are subjected to a variety environmental hazards. Shock and vibration hazards are generally considered the most damaging of the environmental hazards on a product, and it may encounter while passing through the distribution environment. A major cause of shock damage to products is drops during manual handling. The increasing use of unitization on pallets has been resulted in a reduction in the manual handling of products and with it a reduction in the shock hazards. This has caused and increasing interest in research focused on vibration caused damage. the use of pallets as a base for unitizing loads, aids in the mechanical handling, transportation and storage of products. Besides aiding in the handling, transportation and storage of products, a pallet also acts on and interface between the packaged goods and the distribution environment. The determination of the impact deformation of the cushioning materials such as tray cup (polymeric foam) and corrugated fiberboard pad must be carried out to design the proper packaging system providing adequate protection for the fruit, and to understand the complex interaction between the components of fruit when they relate to expected transportation vibration inputs. In this study, the theoretical analysis of impact deformation for cushioning materials by dynamic vibration. The impact deformations of SW and DW corrugated fiberboard pad in acceleration amplitudes of 0.25 G-rms and 0.5 G-rms that were usually generated in transport vehicles during distribution environments were very small compare with the thickness of corrugated fiberboard pad. The maximum of vibration acceleration level of tray cup by vibration impact was about 3.2 G-rms. The theoretical allowable acceleration (G-factor) of the pear was 0.7102 G-rms, and the maximum dynamic deformation estimated within G-factor was about 1 mm.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.10a
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• pp.77-77
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• 2005

• The Journal of Engineering Geology
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• v.16 no.2 s.48
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• pp.201-214
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• 2006

To study the relationship between rainfall conditions and landslides according to a geological condition in land-slides areas such asJangheung Kyounggi, Sangju and Pohang Kyoungbuk, the data of rainfall and landslides are investigated and analyzed. Many landslides occurred at these areas because of the heavy rainfall in two or four days of the summer 1998. The data of rainfall are collected in observatories within a 50km radius from landslides occurrence areas, and the data of landslides are investigated directly in landslides areas. The data of rainfall are the accumulative rainfall and the rainfall intensity, and the data of landslides are the occurrence frequency considering the geological condition. These data are analyzed statistically to know the relationship the rainfall and landslides. The landslides are concentrated in the heavy rainfall area from the analysis of these data. It knows that the land-slides are triggered by the heavy rainfall. Meanwhile, the rainfall factors such as the accumulative rainfall, the rain-fall intensity and the dropping time are different in each landslides area, and the shape and frequency of landslides are different respectively. The landslides have occurred in the area of high accumulative rainfall, while the land-slides have not occurred around that area. Therefore, the rainfall is very important factor induced by the landslides, and the accumulative rainfall is really related to the frequency of landslides.

• 한국노년학
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• v.32 no.2
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• pp.377-395
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• 2012

This study was conducted to develop and evaluate the effectiveness of Multifactorial Fall Prevention Program (MFPP) for local low-income elderly people on physical·psychological, and home environmental hazards, and falling frequency. The selected elderly people was provided the MFPP during an eight-week period of time, once a week, 70 to 90 minutes per each section. The design of this study was non-equivalent control-group with repeated measuring by quasi-experimental study. Data were collected before treatment, 8 week after treatment and 4 week after retention from July to October, 2010. Data were analyzed with numbers, percentage, Fisher's exact test, x²-test, repeated measures ANOVA, ANCOVA and Logistic regression. There were significant differences in fall frequency, balance, fear of falling, fall efficacy, home environmental hazards between the experimental group (EG) and control group (CG). This study showed that the multifactorial fall prevention program(MFPP) was useful nursing intervention for strengthening physical·psychological and environmental functions of the low-income elderly people, as well as preventing fall.