• Journal of Soil and Groundwater Environment
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• v.22 no.5
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• pp.13-22
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• 2017

Accurate assessment of agricultural groundwater usage is an essential task to cope with drought that occurs irregularly in time and location. In this study, the agricultural groundwater usage was calculated in nationwide public wells (1,386 bedrock wells) during 5-year period (2010-2014) by using electric power consumption and well specification data. National average of agricultural groundwater usage per each well was estimated as $66.2m^3/day$, corresponding to 21.6% of total permitted volume of groundwater in each well. Chungcheong Nam-do had the highest usage with 38-55.6%. The value increased to 58.1% when the total permitted volume was based upon the supply standard against drought, and the value reached 100% in Chungcheong Nam-do. In Ganghwa distirct that suffered from severe drought in recent years, the average groundwater usage was 61.4%. In 2014, when the drought was the most severe with 45% precipitation of the average annual rainfall, the nationwide usage was turned out to be 25.6%, indicating about 4% higher than average agricultural groundwater usage 21.6%. Therefore, the quantitative assessment of groundwater usage in this study signifies that adequate use of groundwater is crucial to cope with agricultural drought.

• The Journal of Engineering Geology
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• v.27 no.4
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• pp.383-392
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• 2017

Excessive abstraction of groundwater near streams for agricultural, domestic, or industrial use can significantly reduce the streamflow. Therefore, proper management of water resources must involve careful monitoring of groundwater use near streams. This study investigates the current status of groundwater intake plans in the Anseongcheon watershed, Korea, in order to understand the portion of groundwater wells according to distance from the stream and the distribution of wells near the stream. Among all the wells in the watershed, 20.5% were permitted and 31.3% were declared within 300m from the stream. In particular, among the wells located near streams, 11.4% were permitted and 88.6% were declared among the wells near streams. Therefore, the total amount of groundwater pumping rates from the declared wells is much higher than that from the permitted wells near the stream. Under current guidelines, investigations of the impact of groundwater use near a stream on streamflow depletion should only consider wells permitted by groundwater law. However, prudent management should also pay attention to declared wells, given their large number.

• Steel and Composite Structures
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• v.35 no.2
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• pp.261-278
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• 2020

In steel-concrete composite beams, to improve the cracking resistance of the concrete slab in the hogging moment region, a new type of connector in the interface, named uplift-restricted and slip-permitted screw-type (URSP-S) connector has been proposed. This paper focuses on the behavior of steel-concrete composite beams with URSP-S connectors. A total of three beam specimens including a simply supported beam with URSP-S connectors and two continuous composite beams with different connectors arrangements were designed and tested. More specifically, one continuous composite beam was equipped with URSP-S connectors in negative moment region and traditional shear studs in other regions. For comparison, the other one was designed with only traditional shear studs. The failure modes, crack evolution process, ultimate capacities, strain responses at different locations as well as the interface slip of the three tested specimens were measured and evaluated in-depth. Based on the experimental study, the research findings indicate that the larger slip deformation is allowed while using URSP-S connectors. Meanwhile, the tensile stress reduces and the cracking resistance of the concrete slab improves accordingly. In addition, the overall stiffness and strength of the composite beam become slightly lower than those of the composite beam using traditional shear studs. Moreover, the arrangement suggestion of URSP-S connectors in the composite beam is discussed in this paper for its practical design and application.

• Journal of Chest Surgery
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• v.19 no.2
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• pp.358-362
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• 1986

Esophageal atresia and tracheoesophageal fistula may occur as separate entities but usually occur in combination. Recently we were experienced a case of esophageal atresia with distal tracheoesophageal fistula in infant patient who presented the symptoms of projectile vomiting and dyspnea. The diagnosis was made by the esophagography and the Haight`s operation was performed transpleurally through 4th intercostal space after gastrostomy. Operative patient tolerated all the operative procedures well in spite of postoperative respiratory complication and recovered uneventfully, permitted feeding on 10th postoperative day. On follow up study after 5th months, Patient reveals good health without other problem.

• International Journal of Naval Architecture and Ocean Engineering
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• v.5 no.3
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• pp.325-332
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• 2013

Diffuse interface model for numerical analysis was used to compute supercavitating flows around various cavitators. The ambient pressures of 2 atm permitted cavitation studies in a range of cavitation number, ${\sigma}=0.1$ to 1.0 on selected conical and disk-headed cavitors. The computed results were compared with relation by Reichardt. Drag coefficient obtained from pressure forces acting on the cavitator also compared well with those obtained from analytical relations.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.4
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• pp.21-29
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• 2016

This study was conducted to review Waste Transfer Stations(WTSs) in Seoul, especially focusing on three aspects, main roles, neighbor friendly and regulation compliance, and to draw out recommendation for improvement. The 46 units of all 65 WTSs treated large amount of waste on a day shipping-out schedule, the other 19 WTSs treated small amounts of wastes which were transported after 3~30 days stock. About 57% of WTSs are located in residential or commercial area. Other 57% of WTSs were open without walls. 79% of WTSs were placed alone. Just 17% of WTSs were permitted as environmental infrastructures by urban planning law, and 31% of WTSs were operated by private waste haulers who were permitted by waste management law. Most WTSs in Seoul seemed to go well with on-going policy demand, such as regionalizing waste treatment facilities, expanding waste recycling, and so on. However lots of WTSs did not implement sufficient environmental protection measures, and partly not compliant with regulations related to urban infrastructures. In the future, the issue on sealing facilities and integrating functions of waste management facilities could be considered in order to fit in urban environment.

• Steel and Composite Structures
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• v.36 no.1
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• pp.1-16
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• 2020

In steel-concrete composite beams, to improve the cracking resistance of the concrete slab in the hogging moment region, a new type of connector in the interface, named uplift-restricted and slip-permitted screw-type (URSP-S) connector has been proposed. This paper focuses on the behavior of steel-concrete composite beams with URSP-S connectors. A total of three beam specimens including a simply supported beam with URSP-S connectors and two continuous composite beams with different connectors arrangements were designed and tested. More specifically, one continuous composite beam was equipped with URSP-S connectors in negative moment region and traditional shear studs in other regions. For comparison, the other one was designed with only traditional shear studs. The failure modes, crack evolution process, ultimate capacities, strain responses at different locations as well as the interface slip of the three tested specimens were measured and evaluated in-depth. Based on the experimental study, the research findings indicate that the larger slip deformation is allowed while using URSP-S connectors. Meanwhile, the tensile stress reduces and the cracking resistance of the concrete slab improves accordingly. In addition, the overall stiffness and strength of the composite beam become slightly lower than those of the composite beam using traditional shear studs. Moreover, the arrangement suggestion of URSP-S connectors in the composite beam is discussed in this paper for its practical design and application.

• Biotechnology and Bioprocess Engineering:BBE
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• v.8 no.6
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• pp.331-337
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• 2003

Unicellular green algae of the genus Dunaliella thrive in extreme environmental conditions such as high salinity, low pH, high irradiance and subzero temperatures. Species of Dunaliella are well known in the alga biotechnological industry and are employed widely for the production of valuable biochemicals, such as carotenoids. Some strains of Dunaliella are cultivated commercially in large outdoor ponds and are harvested to produce dry algal meals, such as polyunsaturated fatty acids and oils for the health food industry, and coloring agents for the food and cosmetic industries. During the past decade, the advances in molecular biology and biochemistry of microalgae, along with the advances in biotechnology of microalgal mass cultivation, enabled this microalga to become a staple of commercial exploitation. In particular, the advent of molecular biology and mutagenesis in Dunaliella has permitted enhancements in the carotenoids content of this green alga, making it more attractive for biotechnological applications. Accordingly, the present review summarizes the recent developments and advances in biotechnology of carotenoid production in Dunaliella.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.2B
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• pp.141-147
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• 2011

In this paper, field trials for co-sited transmitters with 600kHz channel separation are performed to investigate the available FM spectrum resource of Korea. Requirements of subjective voice quality and electric field intensity levels are quite well fulfilled during overall field trials. Experimental results show that 600kHz channel separation in co-sited transmitter can be permitted after reasonable pre-simulation and field trial.

• Journal of Chest Surgery
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• v.20 no.3
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• pp.565-569
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• 1987

The first description of the pathologic anatomy of esophageal atresia was presented by Duration in 1670, it was not successfully treated until 1939 when the first two survivors of staged correction were described by Ladd and Levin. In 1941 Haight and Towsley performed the first successful primary repair. Recently we were experienced a case of esophageal atresia with tracheoesophageal fistula an infant patient who presented the symptoms of vomiting and dyspnea. The diagnosis was made by the esophagography with Diagnosis. The operation was performed extrapleurally through 4th intercostal space after gastrostomy. The fistula was closed by triple ligation and the upper pouch was then brought into apposition with the presenting surface of the lower esophageal segment and an end to side anastomosis was fashioned with a single layer of sutures. Operative patient tolerated all the operative procedure well in spite of postoperative respiratory complication and recovered uneventfully, permitted feeding on 9th postoperative day after esophagography.