• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.1D
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• pp.55-61
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• 2009

In this research freezing depth analyses were performed for the recent 9 project field sites using FrostAM which is a freezing analysis model developed recently within the country and a model based on regional environmental factors and physical properties of pavement materials. The environmental factors needed for freezing depth analysis were obtained from the meteorological agency website. And there were laboratory tests and analyses using a measuring device for properties of unsaturated soil for the field site samples across country to obtain hydrographical properties among physical properties. The freezing depths analyzed by FrostAM were deeper in the range of 14cm~44cm than those based on freezing index. It is considered that the freezing depths based on freezing index were overestimated. And there are considerable differences among the freezing depths based on freezing index which were designed by different designers.

• Korean Journal of Occupational Health Nursing
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• v.27 no.1
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• pp.48-58
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• 2018

Purpose: The purpose of this study was to understand the present status of the work performance of the construction industry health managers and the developmental direction for the construction industry health management. Methods: The subjects of this study were 149 health managers working in the construction industry. Data of a total of 130 participants were analyzed by excluding the missing data among field workers. The contents of the survey were the characteristics of the workplace, the difficulties and requirements of health management, and the level of job performance. Results: The factors affecting measuring work environment task were age, number of workers, number of safety managers, and lack of support from the headquarters. The factors affecting managing work environment and physicochemical harmful factors were age, type of contract and conflicting business opinions. The factors affecting implementing health examination were age, type of contract, and number of safety managers. The factors affecting healthcare were age, type of contract, number of safety manager, presence of healthcare room, and conflicting business opinions. Conclusion: It is necessary to provide practical guidance and practical resources, and education for strengthening capacity. The support for business owners and managers support is needed.

• Ecology and Resilient Infrastructure
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• v.4 no.2
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• pp.75-82
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• 2017

This study was executed to know the effect of the habitat size on huanren brown frog (Rana huanrensis) larvae's growth. We've conducted the study on Mt. Surak in Sanggye-dong, Nowon-gu, Seoul. Our study site was discriminated the huanren brown frog larvae's habitat into the three different areas, such as small area (S1, $3.91m^2$), middle area (S2, $4.42m^2$), and large area (S3, $38.37m^2$) in the same water channel. We measured two times per a week the 15 huanren brown frog larvae's body length, and developmental stages (foreleg, hind leg, tail length) including the environmental factors (humidity, air temperature and water temperature) of the study site from March 30 to June 28 in 2016. The only hatching rate was measured for the three egg sacs at the S2 study site. We found that the average hatching rate was $76.84{\pm}18.23(%)$ at S2. Generally, because of less precipitation during our study periods, all habitat areas for our study site were gradually decreased. The middle area, S2, was not reduced, the small area, S1, was reduced more than a fourth, and the largest area, S3, was drastically reduced more than half from initial area. There was no statistically difference among the three study sites for the three environmental factors (average humidity, average air temperature, and average water temperature) by F-test, but there were significant difference among the three site for the larvae's body length (F-test p< 0.05). Therefore, the larger of habitat areas, the larger of the larvae length as well as the faster of the larvae's developmental stages. When we measured the body lengths of immature huanren brown frogs, the immature frog of S1 was smallest, the immature frog of S3 was middle lenght, and the immature frog of S2 was largest. There were statistically different among the three study sites for the immature huanren brown frogs (F-test, p< 0.05). Because the S2 study site was relatively stable without rarely changing the study area, it meant that huanren brown frog was sensitive to habitat areas. Based on the results of this study, if we study on the effect of the altitude on the growth rate of huanren brown frog, it must be helpful in understanding the habitat environment of the population of huanren brown frog.

• Proceedings of the KSRS Conference
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• 2002.10a
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• pp.803-803
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• 2002

Several environmental problems have occurred and extremely affected throughout the East Asia region. Satellite imageries and spatial information have been used in the applications of environmental and natural hazard management for years. Sharing these data and resources in the community is considered as one of the optimal solution. It would consequently bring cost saving to all participated countries and eventually be beneficial to mankind as a whole. Encouraged by these factors, ASEAN＋3 Satellite Image Archive for Environmental Study project was submitted by Thailand in the 3rd Senior Official Meeting between ASEAN, China, Japan and Korea (SEOM＋3 Meeting) and approved by the SEOM＋3. The main objectives of this project are to share satellite images, information related to natural resources and environmental issues, and to provide data information services to all ASEAN＋3 countries. The proposed system is basically embedded by distributed system. The network of data users, data providers, and the center will be established using the Internet. User can access, navigate, display, and even download some archived contents. Its service site can be generally categorized into two parts, which are environmental related data archive and the Integrated satellite image catalogue. The extension of web based GIS is also planned for future development so that GIS users can conduct some preliminary analysis directly on line. This presentation will indicate scope of work, system, working scenario, and work plan of the project.

• Environmental Engineering Research
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• v.23 no.4
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• pp.420-429
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• 2018

Soil stabilization is a soil remediation technique that reduces the mobility of heavy metals in soils. Although it is a well-established technique, it is nonetheless essential to perform a follow-up chemical assessment via a leaching test to evaluate the immobilization of heavy metals in the soil matrix. Unfortunately, a standard chemical assessment is not sufficient for evaluation of the biological functional state of stabilized soils slated for agricultural use. Therefore, it is useful to employ a pyrosequencing-based microbial community analysis for the purpose. In this study, a recently stabilized site in the proximity of an exhausted mine was analyzed for bacterial diversity, richness, and relative abundance as well as the effect of environmental factors. Based on the Shannon and Chao1 indices and rarefaction curves, the results showed that the stabilized layer exhibited lower bacterial diversity than control soils. The prevalence of dominant bacterial populations was examined in a hierarchical manner. Relatively high abundances of Proteobacteria and Methylobacter tundripaludum were observed in the stabilized soil. In particular, there was substantial abundance of the Methylobacter genus, which is known for its association with heavy metal contamination. The study demonstrated the efficacy of (micro)biological assessment for aiding in the understanding and post-management of stabilized soils.

• Journal of the Korean association of regional geographers
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• v.16 no.3
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• pp.315-323
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• 2010

The purpose of this study was to investigate the relationship between the determinant factors of visitors' satisfaction and behavioral intentions to the Shincheon stream in Daegu city. It was found that ecology of the Shincheon stream, signals about ecology, and physical facilities positively influenced overall satisfaction. Physical facilities more positively influenced overall satisfaction. The overall satisfaction positively influenced behavioral intentions. For the future studies, it is necessary to do research visitors' satisfaction with more diverse factors of satisfaction and longitudinal studies about visitors' satisfaction based on seasonally different visitors.

• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.5
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• pp.57-65
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• 2007

The objective of this study was to evaluate chemical water quality by hourly monitoring(25hr) of Saemangeum esturary. For this study, we selected 2 sites like a Mangyong Bridge(St. 6) and Dongjin Bridge(St. 7). Inflow of salt water was not detected during low tide(maximum 553, 508cm) of all stations, while the salinity rises were detected in spring tide(750cm). When 602m of maximum tide was reached, salinity concentration was increased at St. 7, while there was no change in St. 6. Therefore, We know that salinity variation is greatly influenced by tide height at survey site. Also, significant variance of salinity(p<0.05) was found between St. 6 and St. 7 because dike construction made the flood tide move into the Dongjin river. Total suspened solids(TSS) concentration was increased because of the river runoff at St. 6, and also the turbulance and resuspension according to salt intrusion at St. 7. During the high tide, the water discharge from the sea seemed to dilute the nutrient but to elevate TSS concentration in St. 7. Silicate and nitrate concentrations in the studied site were decreased by the mixing of sea water, whereas the evident trend of phosphate concentration was not found. This result can be explained by the phosphorus condition. Phosphorus exists inactive when it is affected by hydrated iron and adsorbed onto suspended matters. Compared to the environmental conditions of the St. 6 and St. 7, physical factors such as temperature, dissolved oxygen and TSS have statistically no significant difference(p<0.001), but nutrient concentrations were higher at St. 6 than St. 7. It could be suggested from these results that it is important to control the discharge of fresh water by sewage treatment plants located in St. 6 for water quality management.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.4
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• pp.99-114
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• 2013

In this study, constructability of ecologocal stream restoration process was evaluated and improved approaches for habitat were suggested. The study site is Gucheon River in Geoje city where conducted ecologocal restoration work within maintaining its flood control function. Application of ecological design factors and constructability in the process from planning to construction was analyzed and its results are as follows: In the process of planning and designing, it was focused more on the naturality of Gucheon River rather than the human convinience and ecological design factors were applied within the ecological capacity of the site. First, the indexes for constructability evaluation is selected. It was classified into three major categories as construction quality, design quality and construction administration system. Each index has details, so there are twenty sub indexes for contractibility evaluation. Second, the evaluation results shows that the index most in need of improvement was plumbing construction, followed by Stone construction and pavement construction. design concept was evaluated as appropriate in entire categories. Finally it is suggested that it can be improved in both process of design to enhance the technology and process of construction to enhance the quality management. The constructability of ecological stream needs adaptive management and it must be discussed with its designing which is at the stage before construction. Also it needs discussion with its designer constantly and feed-back process.

• Toxicological Research
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• v.13 no.1_2
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• pp.49-54
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• 1997

PCBs are classified as B2 (Probable human carcinogen) based on the induction of hepatocellular carcinomas in rats and mice from IRIS (Integrated Risk Information System). About 20 years ago, PCBs were phased out for electrical use in Korea, but PCBs were continuously used in the other field. Lately, there has been increasing concern on possible effects of contaminated soil to the other environment and human health. The purpose of this study is to determine PCBs level in soil at some site and to assess the human exposure doses according to exposure routes for people living within sites which expected to be exposed to PCBs. Pollution level of PCBs on the site was monitored using gas liquid chromatography. To assess the transport of PCBs in soil to plant and to air, various transfer factors(diffusion coefficient, bioconcentration factor etc.) were considered in simple calculations. To calculate the residential exposure doses by routes, some equations were considered using assumption value, which define inhalation, ingestion (soil, plant) and derreal uptake pathway. Computated results will be used as risk assessment information for human health evaluation on contaminated soil.

• Journal of Ginseng Research
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• v.37 no.4
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• pp.491-495
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• 2013

Wood-cultivated ginseng, including roots in its dried form, is produced in forest land without using artificial facilities such as light barriers. To identify suitable sites for the propagation of wood-cultivated ginseng, factor combination technique (FCT) and linear combination technique (LCT) were used with geographic information system and the results were superimposed onto an actual wood-cultivated ginseng plantation. The LCT more extensively searched for suitable sites of cultivation than that by the FCT; further, the LCT probed wide areas considering the predominance of precipitous mountains in Korea. In addition, the LCT showed the much higher degree of overlap with the actual cultivation sites; therefore, the LCT more comprehensively reflects the cultivator's intention for site selection. On the other hand, the inclusion of additional factors for the selection of suitable cultivation sites and experts' opinions may enhance the effectiveness and accuracy of the LCT for site application.