• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.4
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• pp.389-396
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• 2015

This study examined how to improve the Korean Navy diving system, particularly focused on using the mobile saturation diving system. This study determined the range of navy operations, and suggested requirements of mobile saturation diving system from the analysis of previous study and current Navy Diving system. Also, this study examined the use of military strategy in terms of its technical and applicable possibility for the enhancement of current system. In addition, the study analyzed both advantages/disadvantages of importing mobile saturation diving system products and domestic development. To review measures in installing and operating such system, this study included analysis on the effectiveness of individual platform. As the result, the study suggested requirements of mobile saturation diving system to be able to be operated by more than 6 divers for more than 17 days at more than 200m depth. And the study confirmed that there are beneficial to use mobile saturation diving system and current Navy saturation diving system together. However, it is low economical efficiency to change current Navy gas diving system to Saturation diving system. To review measures in installing and operating such system, this study suggested that second ATS-II should be built to be able to install mobile saturation diving system. Also, this study generated an utilization method of the system to use it for training when peacetime, and than it should be installed on other platform to use as additional salvage strength during wartime.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.2
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• pp.926-933
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• 2012

Phosphoric acid used for the production of phosphate fertilizers is synthesized by the reaction of phosphate rock and sulfuric acid. As the reaction is exothermic, yield of phosphoric acid is poor at elevated temperature. Therefore, enhancement in its yield requires the process temperature be maintained by releasing the vapor ($80^{\circ}C$) containing HF and SiF4 through a vacuum cooler. However, these valuable resources; Fand Si, which can be utilized for the manufacture of refrigerant and polysilicon, respectively, are being wasted in the treatment process. We performed lab-scale experiments to estimate the amount of recoverable H2SiF6, a by-product of phosphoric acid manufacturing process. The experimental results showed a decrease of fluorine concentration by 0.12wt% in the liquid phase. Preliminary estimation showed a possible recovery of 5,509 ton/yr of fluorine considering the scale of the fertilizer manufacturing plant. Furthermore, field-scale experiment showed that H2SiF6 could be enriched in liquid phase from 0.35wt% to 7.33wt% and the vapor flow-rate from vacuum cooler was estimated at $51,000m^3/hr$. Anew, the efficiency of fluorine recovery in the pilot-scale experiment was found to be 76.74% and the production of H2SiF6 was estimated at 5,340 ton/yr.

• Journal of Industrial Convergence
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• v.18 no.4
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• pp.111-123
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• 2020

This study analyzed current use of 2-block haircut styles and preferences for accurate understanding of the haircut and enhancement of its efficiency. For this, a questionnaire survey was performed against 441 men in their 20~40s living in Jeollanam-do from June 27 to July 6, 2019. A total of 430 copies were used for final analysis. The collected data were analyzed by frequency analysis and cross-tabulation analysis, using SPSS 21.0, and the results found the followings: When asked about the factors affecting their choice of the haircut, 58.4% (20~40s in age) responded, 'my own decision'. Second, 61.2% said that they were interested in a 2-block haircut, and 54.7% responded that they had the haircut before. Among them, 92.3% said that they were satisfied with the trendy undercut. The above results confirm that men's appearance management is now essential, considering changes in social environments. People envision their hairstyle and visit a hair salon based on their own will, not after recommendation from their acquaintances. Many customers prefer a 2-block haircut because they believe it looks good on them. In addition, they choose the easy-to-care undercut to have a clean and neat image. It is anticipated that the study results would make a contribution to suggesting basic academic data and enhancing sales in a 2-lock haircut which is expected to remain popular. Therefore, it proposes in-depth studies on new 2-block haircut styles for women.

• The Journal of Society for e-Business Studies
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• v.22 no.3
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• pp.87-103
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• 2017

In recent years, many small and medium-sized manufacturing companies are making process innovation and product innovation through the public knowledge services. K Research institute provides different types of knowledge services in combination and due to this complexity, it is difficult to analyze the performance of knowledge service programs precisely. In this study, we derived performance items from bottom-up viewpoints, rather than top-down approaches selecting those items as in previous performance analysis. As a result, 74 items were finded from 82 companies in the K Research Institute case book, and the final result was refined to 17 items. After that a case-performance matrix was constructed, and binary data was entered to analyze. As a result, three clusters were identified through K-means clustering as 'enhancement of core competitiveness (product and patent),' 'expansion of domestic and overseas market,' and 'improvement of operational efficiency.'

• Agribusiness and Information Management
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• v.9 no.1
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• pp.7-17
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• 2017

Agricultural water management has gained enormous attention in the developing world to alleviate poverty, reduce hunger and conserve ecosystems in small-scale production systems of resource-poor farmers. The story of food security in the $21^{st}$ century in India is likely t o be closely linked to the story of water security. Today, the water resource is under severe threat. The past experiences in India in general and in Andhra Pradesh in particular, indicated inappropriate management of irrigation has led to severe problems like excessive water depletion, reduction in water quality, water logging, salinization, marked reduction in the annual discharge of some of the rivers, lowering of ground water tables due to pumping at unsustainable rates, intrusion of salt water in some coastal areas etc. Considering the importance of irrigation water resource efficiency, Krishna Western Delta (KWD) of Andhra Pradesh was purposively selected for this in depth study, as the farming community in this area are severely affected due to severe soil salinity and water logging problems and hence, adoption of different water saving crop production technologies deserve special mention. It is quite disappointing that, canals, tube wells and filter points and other wells could not contribute much to the irrigated area in KWD. Due to less contribution from these sources, the net area irrigated also showed declining growth at a rate of -6.15 per cent. Regarding paddy production, both SRI and semi-dry cultivation technologies involves less irrigation cost (Rs. 2475.21/ha and Rs. 3248.15/ha respectively) when compared to transplanted technology (Rs. 4321.58/ha). The share of irrigation cost in Total Operational Cost (TOC) was highest for transplanted technology of paddy (11.06%) followed by semi-dry technology (10.85%) and SRI technology (6.21%). The increased yield and declined cost of cultivation of paddy in SRI and semi-dry production technologies respectively were mainly responsible for the low cost of production of paddy in SRI (Rs. 495.22/qtl) and semi-dry (Rs. 532.81/qtl) technologies over transplanted technology (Rs. 574.93/qtl). This clearly indicates that, by less water usage, paddy returns can be boosted by adopting SRI and semi-dry production technologies. Both the system-level and field-level interventions should be addressed to solve the issues/problems of water management. The enabling environment, institutional roles and functions and management instruments are posing favourable picture for executing the water management interventions in the State of Andhra Pradesh in general and in KWD in particular. This facilitates the farming community to harvest good crop per unit of water resource used in the production programme. To achieve better results, the Farmers' Organizations, Water Users Associations, Department of Irrigation etc., will have to aim at improving productivity per unit of water drop used and this must be supported through system-wide enhancement of water delivery systems and decision support tools to assist farmers in optimizing the allocation of limited water among crops, selection of crops based on farming situations, and adoption of appropriate alternative crops in drought years.

• Journal of Plant Biotechnology
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• v.44 no.1
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• pp.56-60
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• 2017

This study investigated the in vitro symbiotic seed germination of the achlorophyllous orchid, Gastrodia elata, using a new Mycena species. A leaf-disc ($2{\times}2cm$) of Quercus accutissima was inoculated with either of the two fungal species, NIFOS101 (NCBI accession number KY449288) or KFRI1212 (HQ662845), following which it was placed on water agar medium, prior to sowing seeds of G. elata. After 20 days of symbiotic culture, NIFOS101 and KFRI1212 germinated 94% and 70% of G. elata seeds, respectively, although the initiation of protocorm development was induced much earlier by KFRI 1212 than by NIFOS101. Furthermore, the NIFOS101 mycelia grew much faster than KFRI 1212 at all temperatures tested. A phylogenetic analysis using the internal transcribed spacer (ITS) sequences showed that NIFOS101 belonged to a clade with M. purpureofusca, which completely differed from the clade with KFRI1212. This study not only identified a new fungal species, NIFOS101, which improved the rate of symbiotic seed germination up to 94% as compared to KFRI1212 (70%), but also revealed that G. elata required a broad taxonomic range of fungi for its symbiotic germination.

• Journal of the Korean Electrochemical Society
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• v.18 no.1
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• pp.38-44
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• 2015

This review article summarizes the recent progress of quantum dot (QD)-sensitized solar cells based on mesoporous $TiO_2$ thin films. From the intrinsic characteristics of nanoscale inorganic QDs with various compositions, it was possible to construct a variety of 3rd-generation thin film solar cells by solution process. Depending on preparation methods, colloidal QD sensitizers are pre-prepared for later deposition onto the surface of $TiO_2$ or in-situ deposition of QDs from chemical bath is done for direct growth of QD sensitizers over substrates. Recently, colloidal QD sensitizers have shown an overall power conversion efficiency of ~7% by a very precise control of composition while a representative CdS/CdSe from chemical bath deposition have done ~5% with polysulfide electrolytes. In the near future, it is necessary to carry out systematic investigations for developing new hole-conducting materials and controlling interfaces within the cell, thus leading to an enhancement of both open-circuit voltage and fill factor while keeping the current high value of photocurrents from QDs towards more efficient and stable QD-sensitized solar cells.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.7
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• pp.36-45
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• 1999

In order to control the flow of traffics in ATM networks and optimize the usage of network resources, an efficient control mechanism is necessary to cope with congestion and prevent the degradation of network performance caused by congestion. In this paper, Buffered Leaky Bucket which applies the same control scheme to a variety of traffics requiring the different QoS(Quality of Service) and Neural Networks lead to the effective buffer utilization and QoS enhancement in aspects of cell loss rate and mean transfer delay. And the cell scheduling algorithms such as DWRR and DWEDF for multiplexing the incoming traffics are enhanced to get the better fair delay. The network congestion information from cell scheduler is used to control the predicted traffic loss rate of Neural Leaky Bucket, and token generation rate and buffer threshold are changed by the predicted values. The prediction of traffic loss rate by neural networks can enhance efficiency in controlling the cell loss rate and cell transfer delay of next incoming cells and also be applied for other traffic controlling schemes. Computer simulation results performed for random cell generation and traffic prediction show that QoSs of the various kinds of traffcis are increased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.92-97
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• 2002

The effects of Pueraria flos (PF) and Pueraria radix (PR) water extract on the hepatic alcohol metabolic enzyme activities were examined in rats that were orally administered ethanol (25% v/v, 5g/kg body weight/day) for 5 weeks. The PF and PR water extract were supplemented in a diet, based on 1.2 g or 2.4 g of raw PF or PR/kg body weight/body. Alcohol administration without the PF or PR supplementation significantly decreased net weight gain, feed intake and feed efficiency ratio. However. both dose of the PF of PR supplementation resulted in significant enhancement of growth and suppression of increased relative weight of liver, brain and heart by alcohol administration. Activities of hepatic alcohol dehydrogenase and microsomal ethanol oxidizing system were higher in the alcohol treated group than in the normal group, while aldehyde dehydrogenase activity was significantly lowered in the alcohol treated group. The hepatic metabolic enzyme activities altered by alcohol administration were normalized by both doses of PF or PR supplement. Hepatic monoamine oxidase activity and hydrogen peroxide, which were significantly higher in the alcohol treated group than in the normal group, were also decreased by the supplementation with either PF or PR. These results indicate that low-or high-supplementation of either water extract PF or PR may alleviate ethanol-induced hepatotoxicity by altering alcohol metabolic enzyme activities.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.1
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• pp.67-71
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• 2010

Impingement of a high power laser pulse (above 1 GW/$cm^2$) on a metal foil causes its ablation, which is characterized by a rapid expulsion of matter and the initiation of a strong shock wave inside the solid metal. The shock propagates through the foil and reverberates on the rear side, causing its deformation and microparticle ejection, which were deposited on the foil prior to ablation. Based on this principle, we are developing a new drug delivery system - Biolistic gun. Current study is focused on the controllability, stability, efficiency of the system, and characterization of the penetration shapes in various conditions. We have tested the system by applying direct and confined ablation. Several different media combinations were used for confinement-BK7 glass, water, BK7 glass with water, and succulent jelly(ultrasono jelly, RHAPAPHRM). Biological tissue was replicated by a 3% gelatin solution. Present data shows that the confinement results in enhancement of penetration shape reached by 5 um cobalt microparticles. Based on the analysis of the experimental results we observe that the penetration shape of microparticles can be controlled by adjusting the thickness of confinement media.