• Journal of Korea Water Resources Association
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• v.45 no.5
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• pp.495-503
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• 2012

It is necessary to perform the precise analysis of unsteady flow for effective design of the side-weir detention basin installed in the river. Generally, the HEC-RAS program, which is a 1D unsteady numerical model, is mostly used to simulate the unsteady flow for rivers. However, it is difficult to have confidence of unsteady flow results simulated by HEC-RAS due to the lack of experimental data and field monitoring data for the channel with a side-weir detention basin. Therefore, the purpose of this study is to validate or verify the simulation results calculated by HEC-RAS through the experiments for the open channel with a side-weir detention basin using specially-designed unsteady discharge-supply system. The experimental cases included unsteady flows in the straight channel with and without a side-weir detention basin. Especially, for the case with a detention basin, the experiment was performed to consider only the free flow condition over the side-weir. The study results showed that values of water level and discharge obtained from HEC-RAS coincided reasonably with experimental results with the maximum error of 3% for water level and 1% for discharge in the case of the flow without the side-weir detention basin and 4% for water level and 2% for discharge with the side-weir detention basin.

• Journal of Chest Surgery
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• v.31 no.3
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• pp.279-285
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• 1998

Exessive sweating of the palms and soles, is a psychologically and occupationally distressing and sometimes disabling condition. Hyperhidrosis is one of the common abnormalities in autonomic nervous system. There were no specific treatment on hyperhidrosis, so invasive thoracic sympathectomy via axillary thoracotomy or cervical approach had been used. Video-assisted thoracic surgery(VATS) is now mostly performed for treating of the palmar and axillary hyperhidrosis. From March 1996 to March 1997, 15 patients with bilateral palmar hyperhidrosis had been treated by the bilateral thoracic sympathectomy(T2, T3, T4) with thoracoscopic resection. The patient were evaluated preoperative and postoperative Digital Infrared Thermographic Imaging (DITI) at Kyung-Hee University Hospital. There were no case of the thoracotomy conversion. There were 3 complications ; pulmonary edema in 1 case, Horner's syndrome in 1 case, and gustatory hyperhidrosis in 1 case. More than half of the patients also had compensatory sweating in the lower abdomen, the buttocks, the back and the thighs. In conclusion, most of the patients were satisfied with the postoperative results of the thoracoscopic sympathectomy, including no more palmar and axillary sweating, less pain, better cosmetic appearances, decreased sweating of the face and soles. In addition, intraoperative temperature monitoring of the hands could estimate the successful thoracoscopic sympathectomy and the preoperative and postoperative Digital infrared thermographic imaging(DITI) could especially be the technique for the objective manifestation of the successful results of the thoracoscopic sympathectomy.

• Membrane Journal
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• v.27 no.4
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• pp.367-373
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• 2017

Pressurized membrane module systems, including hollow fiber type of Microfiltration (MF) and Ultrafiltration (UF) membranes are being increasingly used in drinking water treatment due to their high removal efficiency of pathogen. However, when fibers are damaged in pressurized membrane system, the pathogen will be able to penetrate the membrane. Therefore, it is essential to guarantee the regulatory requirements for water quality by an effective on-line or off-line condition integrity monitoring methods. Recently, pressure decay test (PDT) which is one of membrane integrity tests has been reflected to drinking water treatment plants using pressurized membrane module. In this paper, three different method were used to perform PDT and three different sensitivity values were analyzed through experiments. Three types of direct integrity test methods were applied to pressure feed side, filtrate side and bidirectional pressure decay test. The results of these experiments show that the sensitivity was increasing when the volume of pressurized gas was decreasing. The sensitivity is inversely proportional to the gas volume. Furthermore, it is desirable to increase pressure difference between feed side and permeate side in order to achieve higher sensitivity in the PDT by membrane damage.

• Journal of Environmental Science International
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• v.17 no.9
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• pp.1053-1068
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• 2008

This study aims to produce fundamental database for Environment Impact Assessment by monitoring vertical structure of the atmosphere due to the mountain valley wind in spring season. For this, we observed surface and upper meteorological elements in Sangin-dong, Daegu using the rawinsonde and automatic weather system(AWS). In Sangin-dong, the weather condition was largely affected by mountains when compared to city center. The air temperature was low during the night time and day break, and similar to that of city center during the day time. Relative humidity also showed similar trend; high during the night time and day break and similar to that of city center during the day time. Solar radiation was higher than the city, and the daily maximum temperature was observed later than the city. The synoptic wind during the measurement period was west wind. But during the day time, the west wind was joined by the prevailing wind to become stronger than the night time. During the night time and daybreak, the impact of mountain wind lowered the overall temperature, showing strong geographical influence. The vertical structure of the atmosphere in Dalbi valley, Sangin-dong had a sharp change in air temperature, relative humidity, potential temperature and equivalent potential temperature when measured at the upper part of the mixing layer height. The mixing depth was formed at maximum 1896m above the ground, and in the night time, the inversion layer was formed by radiational cooling and cold mountain wind.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.7
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• pp.754-759
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• 2015

Nowadays, short distance communication systems with low power energy (LPE) are developed for identification and monitoring of site identification of vessel crews and passengers (SIVCP). LPE communication modules, such as Bluetooth low energy (BLE) and Zigbee, are used for short distance communications with LPE. These modules enable 1:N communications and their popularity is growing since the modules can be mounted on movable objects, such as mobile devices and human body. When these modules are used, the important factor that affects their operation time and design are the capacity and size of battery. Therefore, they must be made as small as possible, and the battery should be selected to be slightly smaller than the module. In this study, we calculate the theoretical life of batteries used in SIVCP BLE modules using data sheet and discharge characteristic graph under the condition of a 1/250 transmission-ratio (TR). We thus calculate experimental life by measuring transmission current for the same TR, and low speed mode current for a 1/5000 TR and measure long-term experimental life using 1/25 TR for days. Through these experiments, we verify experimental methods for the prediction and extension of battery life that would enable us to select appropriate sizes of batteries based on vessel usage and passenger types. The selections of the module TR and battery size are important factors affecting the cost reduction of module design, the battery maintenance, and passenger convenience.

• Korean Journal of Remote Sensing
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• v.33 no.5_3
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• pp.763-771
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• 2017

The purpose of this paper is to review the background and purpose of the special issue on Theory of Environment Geospatial Information and Its Applications in Korean Journal of Remote Sensing. The significance of the paper was also discussed. Environmental information refers to environment related information (literature, statistics, images, etc.) in a comprehensive manner. Such environmental information as a local change or issue of the environment is defined as environmental spatial information by developing in a spatial form. Remote sensing data is very useful as direct or indirect data including environmental spatial information on wide-area and local environment. Various applications will be possible not only in the environmental field through several improvements. For this purpose, first, refining and scientificization of technology to build environmental spatial information could be performed. Second, the application field can be expanded by developing the concept and contents of existing environmental spatial information. The third method is continuous increase of the application of existing environmental spatial information. In this paper, the direction of development was examined that reflects recent changes of environmental spatial information such as conversion of data formats and integration with ICT (Information and Communications Technologies). In particular, the basic technology for the construction of environmental spatial information was reviewed through various papers. Through the studies related to the above, utilization of domestic environmental spatial information would be diversified. Also, the development of environment policy and efficient management of environmental factors could be possible.

• Korean Journal of Environmental Agriculture
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• v.17 no.1
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• pp.26-33
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• 1998

This experiment was conducted to classify the plant species occurring in the saline reclaimed land by saline tolerance. The vegetation of reclaimed land was composed of various plant species from halophyte to glycophyte showing different saline tolerances. In the investigated saline region, reclaimed land of Youngjong island, Inchun city, 175 species belonging to 32 families were found. Our survey was carried out in two region, having different salinity due to different desalinization. The electricalconductivity (EC) of more saline region showed 48.0mS/cm nd the other region showed 13.0mS/cm. It is assumed that intensity of precipitation and runoff of rainfall may cause salinity gradient in the investigated region. The plant species occurred in the experimental region were classified as 72 species of annual, 42 species of biennial, and 61 species of perennial according to life cycle. For knowing relationship between vegetation of saline region and saline tolerance of occurring species, we tested the saline susceptibility of plant species collected at the saline regions. Testing plants were cultured by nutrient solution containing 200 mM NaCl, the critical concentration of survival in glycophytes. The saline tolerance was graded by the growing capacity in the sand-culture system. The more saline-tolerant species screened by sand culture were Atriplex gmelini, Suaeda asparagoides, Aster tripolium, Suaeda maritima, Salicornia herbacea, and Suaeda japonica. The most saline tolerant family was Chenopodiaceae. Poaceae, Cyperaceae, and Brassicaceae showed relatively high tolerance to saline stress. In the course of growth under the high saline condition, the most noticeable change was the darkening of leaves by increasing of chlorophyll content. The chlorophyll contents were increased with saline stress in most species.

• Ecology and Resilient Infrastructure
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• v.1 no.1
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• pp.39-48
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• 2014

In order to establish fundamental data for stream restoration and environmental flow, we investigated optimal ecological flowrate (OEF) and riverine health condition in the Chogang Stream, a tributary to Geum River, Korea. The number of fish individuals sampled in this period were 4,669 in 36 species of 9 families. The most abundant species was Korean chub (Zacco koreanus, 34.0%) followed by pale chub (Z. platypus, 22.6%) and Korean shinner (Coreoleuciscus splendidus, 13.3%). Index of biological integrity (IBI) and qualitative habitat evaluation index (QHEI) values decreased from upstream to downstream along the stream. The estimated IBI value ranged from 27.9 to 38.6 with average 32.2 out of 50, rendering the site ecologically fair to good health conditions. OEF was estimated by the physical habitat simulation system (PHABSIM) using the habitat suitability indexes (HSI) of three fish species Z. koreanus, C. splendidus and Pseudopungtungia nigra selected as indicator species. In Z. koreanus, HSI for flow velocity and water depth were estimated at 0.1 to 0.4 m/s and 0.2 to 0.4 m, respectively. In P. nigra, HSI for flow velocity, water depth and substrate size were estimated at 0.2 to 0.5 m/s and 0.4 to 0.6 m and fine gravel to cobbles, respectively. OEF values increasing from up to downstream was found to increase, weighted usable area (WUA) values increased accordingly.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.2
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• pp.121-130
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• 2010

Metals and sulfate can be considerably dissolved at low pH condition in the acid mine drainage(AMD) and it would make an environmental problems. There are only few of acid mine drainage treatment systems in Korea which are operating, but these still have an effect on the surrounding stream. In this study, quantification of indicator microorganisms was conducted to judge the environmental impact of AMD on microflora by quantitative real-time PCR in the drainage samples of four mines and the water samples of each surrounding stream. Two species of iron reducing bacteria(Rhodoferax ferrireducens T118 and Acidiphilium cryptum JF-5) were selected for indicator bacteria based on 16S rRNA cloning analysis, and sulfate reducing bacteria(Desulfosporosinus orientus), iron and sulfur oxidizing bacteria(Acidothiobacillus ferrooxidans) and iron oxidizing bacteria(Leptosprillum ferrooxidans) were included into indicator since these were found in the previous studies on the mining area. Thereafter, the comparative analysis of four mines were established by the microbiological variation index and it was determined that the biological environment effect of AMD is highest in Samtan mine which doesn t contain treatment system by the value.

• The Journal of Traditional Korean Medicine
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• v.15 no.1
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• pp.128-144
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• 2006

This Study aims at looking into the use of oriental medical services in treating hypertension. The first objective to be explored through this study is the morbidity caused by the disease, classifying them by age, gender, and occupation. The second is to determine the regular use of anti-hypertensive medicine and their efficacy in controlling blood-pressure. The third is to investigate the use-rate and satisfaction of oriental medical service. 838 households across the country, were asked to answer questionnaires for the period of time from Apr. to Jun. 2005. The conclusion from the survey can be summarized as following. The age of which the first medical diagnosis of hypertension were made showed lower in males, those with higher education and income. The study showed females were more active in blood-pressure control, with their frequent monitoring of blood-pressure for the past year. With age, people in under 50 age group proved to be less active. The management of high blood pressure was more effective in group with regular dosage compared to group with irregular use of anti-hypertensive medication, but their difference was minimal. Also, group with no medication showed signs of blood-pressure control. The use of oriental medical service for the past year, were more frequent in groups with lower education, either low or high income, old age, females and occupations in agriculture, forestry and fishing industry. Results were similar in both general population and high blood-pressure patient group. Females, people over 51 years old and with lower education showed more intentions in utilizing oriental medical services in the future. Results were similar in both general population and high blood-pressure patient group. It is necessary to offer a more accurate information on oriental medical treatments. Also, a systematic reform to reduce the patient's share of the treatment cost, as well as, heightening public awareness on the infirmity of present blood-pressure management system is crucial.