• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.1
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• pp.48-57
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• 2015

In a sodium-cooled fast reactor, which is a Generation-IV reactor, refueling is conducted by rotating, but not opening, the reactor head to prevent a reaction between the sodium, water and air. Therefore, an inspection technique that checks for the presence of any obstacles between the reactor core and the upper internal structure, which could disturb the rotation of the reactor head, is essential prior to the refueling of a sodium-cooled fast reactor. To this end, an ultrasound-based inspection technique should be employed because the opacity of the sodium prevents conventional optical inspection techniques from being applied to the monitoring of obstacles. In this study, a ranging inspection technique using a plate-type ultrasonic waveguide sensor was developed to monitor the presence of any obstacles between the reactor core and the upper internal structure in the opaque sodium. Because the waveguide sensor installs an ultrasonic transducer in a relatively cold region and transmits the ultrasonic waves into the hot radioactive liquid sodium through a long waveguide, it offers better reliability and is less susceptible to thermal or radiation damage. A 10 m horizontal beam waveguide sensor capable of radiating an ultrasonic wave horizontally was developed, and beam profile measurements and basic experiments were carried out to investigate the characteristics of the developed sensor. The beam width and propagation distance of the ultrasonic wave radiated from the sensor were assessed based on the experimental results. Finally, a feasibility test using cylindrical targets (corresponding to the shape of possible obstacles) was also conducted to evaluate the applicability of the developed ranging inspection technique to actual applications.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.2
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• pp.34-44
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• 2020

The purpose of this study was to investigate the difference in perceptions between gardens and park functions as recognized by two groups, Group A and Group B, in order to confirm the distinction between concepts and functions and then establish the importance of individual functions. The AHP was used to analyze the importance of each group's perceptions by dividing them into garden and park, Group A and non-Group A, respectively. In Group A, the importance of garden functions were considered in descending order of importance to be cultural function, ecological function, and social function. In the general group, ecological function, cultural function, and social function also appeared, but in a different order of importance. As for the park functions, Group A recognized the importance of functions in a similar order of importance to the gardens: cultural function, ecological function, and social function. Group B thought that social function, ecological function, and cultural function have the same significance. At the major classification level, Group A and Group B emphasized the social function of the parks. Group A recognized the importance of the garden's cultural function as the most important, whereas the general group emphasized the importance of the garden's ecological function. As for the mid-class level, Group A recognized the aesthetic beauty, health, ecological environment protection, and water circulation as important functions of the garden. For Group B, the ecological environment protection, aesthetic beauty, water cycle, and health were important. The concepts and functions of gardens and parks are still largely mixed but are gradually becoming differentiated. As a follow-up study, it is important to systematically manage the functions of gardens by establishing design, construction, and monitoring DB techniques for the garden type and examine the hierarchy of various other gardens.

• Korean Journal of Animal Reproduction
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• v.23 no.3
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• pp.247-256
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• 1999

The present study was performed to improve the reproductive disturbance as well as the elimination of microbiological contamination for animals bred under conventional conditions followed by in vitro fertilization and embryo transfer techniques including embryo and sperm freezing, using a mouse strain(M. m. molossinus-tt＠Kist) showing the abnormal behavior disorder derived from Korean wild mice (Mus musculus molossinus). Moreover, hematological and serum biochemical analyses were also carried out to obtain the basic data of this mouse strain The results are summarized as follows: 1. In comparison with hematological data, the numbers of RBC and platelet of this mouse strain were appeared as the higher value those that of the same aged inbred strains such as BALB/c, DBA/2, C57BL/6 and C3H /Hen. However, no differences were found in values of WBC, Hb and Ht. Moreover, total cholesterol of this strain showed a low value but triglyceride, total protein and albumin values were similar as in inbred strains. 2. The average numbers of superovulated oocytes treated with 2.5/2.5 IU and 5.0/5.0 IU of PMSG/hCG were 11.6 and 12.7, respectively. The fertilization rates of 2.5/2.5 IU PMSG /hCG treatment(87.9%) was higher than 5.0/5.0 IU treatment(52.0%) (p＜0.05) and the developmental rate of 2 cell stage embryos were 외 so appeared as higher value 99.0% and 90.6%, respectively. 3. The rates of in vitro fertilization treated with frozen sperm(24.8%) was significantly lower than of that fresh sperm(87.9%), (p＜0.05). 4. The five, six and ten heads of offspring were obtained from frozen-thawed 2 cell embryos by in vitro fertilized, 2 cell embryos from in vitro fertilized by frozen-thawed spermatozoa. and 2 cell embryos by in vitro fertilization, respectively. These offspring developed the expected disease about 2 weeks after birth, which was confirmed that the disease character of this mutant mouse strain was reliably reproduced. 5. MHV(Mouse hepatitis virus) and Staphylococcus aureus were successfully eliminated from conventional animals by in vitro fertilization-embryo transfer and the use of SPF recipient animals.

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.1
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• pp.29-37
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• 2008

This study examined principles and techniques of efficient water quality management as well as total coastal pollutant loads and the relevant examples in the advanced countries from the viewpoints of water quality improvement and pollution control in coastal areas. The problems and improvements in an estimation of the current total pollutant loads were also pointed out. In addition, discussion was made on the relationship between total pollutant loads and environmental capacity as well as particulars requiring extensive examination on access to and study on water quality model used as prediction tool for marine environment. Furthermore, this study proposed details of and improvement plans for water quality control to be reflected and absorbed into systems and policies related to coastal water quality. In coastal areas, which are subject to total coastal pollutant loads, it is necessary to calculate pollutant loads reduction and allocation, to propose them in detail in statement in relations to new pollution sources for the corresponding projects or plans in environmental impact assessment and prior environmental review system. Also, in relations to regional plans for coastal management, the local government concerned must focus more on environmental management plan to implement data on pollution sources and pollutant loads flown into sea areas under basic jurisdiction, therefore it is required to actively respond to expansion and introduction of total coastal pollutant loads system in the future. Total coastal pollutant loads system must be expanded and executed by considering characteristics of sea area and changes in the environment of land. For pollution sources in land, the competent authorities in charge of coastal environment will need to initiatively administer supervision, monitoring activities and achieve integration and operation of the related laws by preparing legal bases for management system or adjusting the related laws.

• Journal of Chest Surgery
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• v.35 no.11
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• pp.799-806
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• 2002

In spite of the establishment of chemotherapy and the gradual decrease in prevalence, pulmonary tuberculosis is still mainly treated with an operation. Through analyzing and examining some cases of surgical treatment, we hope to provide some help in treating of pulmonary tuberculosis in the future. Material and Method: By comparing four journals previously published in our department with 144 cases of lung surgery during ten years from January of 1991 to December of 2000 performed by the department of thoracic and cardiovascular surgery of the National Medical Center, we analyzed and reviewed the most recent trends and the results of the surgical treatment. Annual frequency of the operation, distribution of age, examination of sputum, adaptability and types of techniques, complications, and results of the postoperative follow-up were used as methods. Result: It was found that the annual frequency of operations had decreased. The ratio of men to women, 2:1 indicates that there are more incidences in men. Aging of patients could be speculated by the .results that the decrease in the incidence rate in the 20s age range and increase rate in the 50s age range. The range of preoperative lesions belonged mostly to far advanced and moderately advanced tuberculosis. By monitoring the period of use in preoperative antituberculosis drugs, cases for more than 3 years remarkably increased from 16.0 % to 55.6 %. The positive reactive rate for preoperative sputum examinations were drastically decreased from 91 % to 27 %. Total pulmonary destruction and partial destruction were the most common cases in terms of adaptability to the operations and there were significant increases in forming empyema accompanied by parenchymal lesions from 4.0 % to 20.1 %. Pneumonectomy and pulmonary lobectomy were the major type of operations. Especially, there were increases in the incident rate of empyema and recurrence of tuberculosis resulted. Post operative follow-up indicates that the rate of complete recovery was more than 70 % and the rate of gradual increase in treating with persistent antituberculosis drug was from 5.8 % to 18.0 %. Conclusion: In recent cases, there is an increasing number of patients showing tolerance to chemotherapy. Patients with pleural tuberculosis and severe lesions were typically increased. It is important to accurately analyze those complaints accurately that are mostly difficult to be treated medically. Surgical treatment is strongly recommended Before multiple drug resistance occurs.

• Journal of Korea Water Resources Association
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• v.53 no.10
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• pp.845-859
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• 2020

Climate change and recent heat waves have drawn public attention toward other environmental issues, such as water pollution in the form of algal blooms, chemical leaks, and oil spills. Water pollution by the leakage of chemicals may severely affect human health as well as contaminate the air, water, and soil and cause discoloration or death of crops that come in contact with these chemicals. Chemicals that may spill into water streams are often colorless and water-soluble, which makes it difficult to determine whether the water is polluted using the naked eye. When a chemical spill occurs, it is usually detected through a simple contact detection device by installing sensors at locations where leakage is likely to occur. The drawback with the approach using contact detection sensors is that it relies heavily on the skill of field workers. Moreover, these sensors are installed at a limited number of locations, so spill detection is not possible in areas where they are not installed. Recently hyperspectral images have been used to identify land cover and vegetation and to determine water quality by analyzing the inherent spectral characteristics of these materials. While hyperspectral sensors can potentially be used to detect chemical substances, there is currently a lack of research on the detection of chemicals in water streams using hyperspectral sensors. Therefore, this study utilized remote sensing techniques and the latest sensor technology to overcome the limitations of contact detection technology in detecting the leakage of hazardous chemical into aquatic systems. In this study, we aimed to determine whether 18 types of hazardous chemicals could be individually classified using hyperspectral image. To this end, we obtained hyperspectral images of each chemical to establish a spectral library. We expect that future studies will expand the spectral library database for hazardous chemicals and that verification of its application in water streams will be conducted so that it can be applied to real-time monitoring to facilitate rapid detection and response when a chemical spill has occurred.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.44-63
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• 2000

Situated close to Heathrow Airport, and adjacent to the M4 and M25 Motorways, the site at Axis Park is considered a prime location for business in the UK. In consequnce two of the UK's major property development companies, MEPC and Redrew Homes sought the expertise of Intergeo to remediate the contaminated former industrial site prior to its development. Industrial use of the twenty-six hectare site, started in 1936, when Hawker Aircraft commence aircraft manufacture. In 1963 the Firestone Tyre and Rubber Company purchased part of the site. Ford commenced vehicle production at the site in the mid-1970's and production was continued by Iveco Ford from 1986 to the plant's decommissioning in 1997. Geologically the site is underlain by sand and gravel, deposited in prehistory by the River Thames, with London Clay at around 6m depth. The level of groundwater fluctuates seasonally at around 2.5m depth, moving slowly southwest towards local streams and watercourses. A phased investigation of the site was undertaken, which culminated in the extensive site investigation undertaken by Intergeo in 1998. In total 50 boreholes, 90 probeholes and 60 trial pits were used to investigate the site and around 4000 solid and 1300 liquid samples were tested in the laboratory for chemical substances. The investigations identified total petroleum hydrocarbons in the soil up to 25, 000mg/kg. Diesel oil, with some lubricating oil were the main components. Volatile organic compounds were identified in the groundwater in excess of 10mg/l. Specific substances included trichloromethane, trichloromethane and tetrachloroethene. Both the oil and volatile compounds were widely spread across the site, The specific substances identified could be traced back to industrial processes used at one or other dates in the sites history Slightly elevated levels of toxic metals and polycyclic aromatic hydrocarbons were also identified locally. Prior to remediation of the site and throughout its progress, extensive liaison with the regulatory authorities and the client's professional representatives was required. In addition to meetings, numerous technical documents detailing methods and health and safety issues were required in order to comply with UK environmental and safety legislation. After initially considering a range of options to undertake remediation, the following three main techniques were selected: ex-situ bioremediation of hydrocarbon contaminated soils, skimming of free floating hydrocarbon product from the water surface at wells and excavations and air stripping of volatile organic compounds from groundwater recovered from wells. The achievements were as follows: 1) 350, 000m3 of soil was excavated and 112, 000m3 of sand and gravel was processed to remove gravel and cobble sized particles; 2) 53, 000m3 of hydrocarbon contaminated soil was bioremediated in windrows ; 3) 7000m3 of groundwater was processed by skimming to remove free floating Product; 4) 196, 000m3 of groundwater was Processed by air stripping to remove volatile organic compounds. Only 1000m3 of soil left the site for disposal in licensed waste facilities Given the costs of disposal in the UK, the selected methods represented a considerable cost saving to the Clients. All other soil was engineered back into the ground to a precise geotechnical specification. The following objective levels were achieved across the site 1) By a Risk Based Corrective Action (RBCA) methodology it was demonstrated that soil with less that 1000mg/kg total petroleum hydrocarbons did not pose a hazard to health or water resources and therefore, could remain insitu; 2) Soils destined for the residential areas of the site were remediated to 250mg/kg total petroleum hydrocarbons; in the industrial areas 500mg/kg was proven acceptable. 3) Hydrocarbons in groundwater were remediated to below the Dutch Intervegtion Level of 0.6mg/1; 4) Volatile organic compounds/BTEX group substances were reduced to below the Dutch Intervention Levels; 5) Polycyclic aromatic hydrocarbons and metals were below Inter-departmental Committee for the Redevelopment of Contaminated Land guideline levels for intended enduse. In order to verify the qualify of the work 1500 chemical test results were submitted for the purpose of validation. Quality assurance checks were undertaken by independent consultants and at an independent laboratory selected by Intergeo. Long term monitoring of water quality was undertaken for a period of one year after remediation work had been completed. Both the regulatory authorities and Clients representatives endorsed the quality of remediation now completed at the site. Subsequent to completion of the remediation work Redrew Homes constructed a prestige housing development. The properties at "Belvedere Place" retailed at premium prices. On the MEPC site the Post Office, amongst others, has located a major sorting office for the London area. Exceptionally high standards of remediation, control and documentation were a requirement for the work undertaken here.aken here.

• Journal of Life Science
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• v.7 no.1
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• pp.1-9
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• 1997

For the recent years, considerable efforts have been made to rationalize the techniques of research and monitoring of biological effects of marine pollutants such as heavy metals, polychlorinate biphenyls (PCBs), organochlorine pesticides, polycyclic aromatic hydrocarbons (PAHs), organophosphorus pesticides. This study was designed as a part of efforts to investigate the biochemical pollutant markers for diagnosis of marine pollutions by the changes in lipid components of the flounder (Paralichthys olivaceus) in Yellow Sea of Korea. Homoglobin levels in serum of cultured and wild flounders in Yellow Sea were significantly lower (5 - 15% and 20 -25 % , respectively) than those of wild flounder in Pohang. Triglyceride (TG) contents in serum of cultured flounders in Yellow Sea were 10 - 40% higher than those of wild flounder in Pohang. Total and low density lipoprotein (LDL)-cholesterol contents in serum of flounders in Yellow Sea were significantly 10-15% and 30-35% (cultured), and 10-20% (wild), respectively, higher than those of wild flounder in Pohang. Atherogenic index (AI) and T-Chol/PL rations in serum of cultured and wild flounders in Yellow sea were significantly 20-45% and 10-!5%, 6-35% and 15-35%, respectively, higher than those of wild flounder in pohang. These results suggest that near-coastal waters as well as neritic waters of the Yellow Sea might be affected by pollutant input.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.10
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• pp.845-854
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• 2009

There has been increased concern regarding the release of antibiotics to different environmental compartments due to the possibility of the development of antibiotic resistant bacteria. However, limited information is available regarding the occurrence, fate, and transport of antibiotics in Korea in both the aqueous phase and in solid phases such as sediment and soil. Therefore, this study was conducted to monitor the concentration of released antibiotics in surface water, sediment, and soil adjacent to a cattle manure composting facility in Korea. Specifically, the following six antibiotics were monitored: tetracycline (TC), chlortetracycline (CTC), oxytetracycline (OTC), sulfamethazine (SMT), sulfamethoxazole (SMX), and sulfathiazole (STZ). To extract and quantify the antibiotics from different environmental compartments, solid phase extraction (SPE) and high performance liquid chromatography mass spectrometry (HPLC/MS) techniques were adopted. The concentration of the six antibiotics ranged from below the detection limit (BDL) to 0.71 ${\mu}g$/L in surface water, from BDL to 27.61 ${\mu}g$/L in sediment, and from 0.12 to 157.33 ${\mu}g$/L in soil. In addition, higher concentrations of antibiotics were observed in surface water and sediment at locations closer to the composting facility indicating that composting is the source of the antibiotics found in the environment. Furthermore, higher concentrations of antibiotics were observed in the solid phase (sediment and soil) than the aqueous phase. These findings indicate that the possibility of antibiotic resistant bacteria is increased because such bacteria are more stable in the solid phase. Overall, longterm monitoring of the aqueous phase and solid phase is necessary to gain a better understanding of the impact of antibiotics from source on the environment in Korea.

• Journal of the Korean Geographical Society
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• v.40
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• pp.1-13
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• 1989

The brightness temperature from NOAA AVHRR CH 4 images was examined for the metropolitan Seoul area, the capital city of Korea, to detect the characteristics of the urban heat island for this study. Surface data from 21 meteorological stations were compared with the brightness temperatures Through computer enhancement techniques, more than 20 heat islands could be recognized in South Korea, with 1 km spatii resolution at a scale of 1: 200, 00O(Fig. 3, 4 and 6). The result of the analysis of AVHRR CH 4 images over the metropolitan Seoul area can be summerized as follows (1) The pattern of brightness temperature distribution in the metropolitan Seoul area shows a relatively strong temperature contrast between urban and rural areas. There is some indication of the warm brightness temperature zone characterrizing built-up area including CBD, densely populated residential district and industrial zone. The cool brightness temperature is asociaed with the major hills such as Bukhan-san, Nam-san and Kwanak-san or with the major water bodies such as Han-gang, and reservoirs. Although the influence of the river and reservoirs is obvious in the brightness temperauture, that of small-scaled land use features such as parks in the cities is not features such as parks in the cities is not apperent. (2) One can find a linerar relationshop between the brightenss temperature and air temperature for 10 major cities, where the difference between two variables is larger in big cities. Though the coefficient value is 0.82, one can estimate that factors of the heat islands can not be explained only by the size of the cities. The magnitude of the horizontal brightness temperature differences between urban and rural area is found to be greater than that of horizontal air temperature difference in Korea. (3) Also one can find the high heat island intensity in some smaller cities such as Changwon(won(Tu-r=9.0$^{\circ}$C) and Po-hang(Tu-r==7.1$^{\circ}$~)T. he industrial location quotient of Chang-won is the second in the country and Po-hang the third. (4) A comparision of the enhanced thermal infrared imageries in 1986 and 1989, with the map at a scale of 1:200, 000 for the meotropolitan Seoul area showes the extent of possible urbanization changes. In the last three years, the heat islands have been extended in area. zone characterrizing built-up area including (5) Although the overall data base is small, the data in Fig. 3 suggest that brightness tempeautre could ge utilized for the study on the heat island characteristics. Satellite observations are required to study and monitor the impact of urban heat island on the climate and environment on global scale. This type of remote sensing provides a meams of monitoring the growth of urban and suburban aeas and its impact on the environment.