• Journal of the Korea Society of Computer and Information
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• v.14 no.8
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• pp.145-152
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• 2009

Manufacturer's competitiveness in the MRO industry, which is to stimulate the growth of the business-to-business e-commerce market, has recently become more important. A nuclear parts manufacturer was supplying products based on irregular demand from clients which differs from ordinary MRO business practices. The reason for this is the Nuclear Parts Manufacturer has fallen behind the e-commerce performance of other industries, and they lack global competitiveness due to the low efficiency of the individual companies within it. In this study, we developed an MRO based a-Marketplace system to minimize repetitive ordering of raw materials, lack of reusability and inefficiency of transaction processing which was a result of the former legacy business practice, In order to accomplish the purpose of this study, we implemented a web based automated CR system which considered the characteristics of the nuclear parts manufacturing: the system has sub modules such as ordering, product management, transaction management, warehousing and raw material handling. As a consequence of the system implementation, H corporate successfully automated ordering of raw materials, quotation processing and inventory management compared to the legacy business process, achieving increased efficiency by reducing wasteful resources.

• Clean Technology
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• v.30 no.2
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• pp.105-112
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• 2024

Globally, the demand for electric vehicles has surged due to greenhouse gas regulations related to climate change, leading to an increase in the production of used batteries as a consequence of the battery life issue. This study aims to selectively leach and recover valuable metal lithium from the cathode material of spent LFP (LiFePO₄) batteries among lithium-ion batteries. Generally, the use of inorganic acids results in the emission of toxic gases or the generation of large quantities of wastewater, causing environmental issues. To address this, research is being conducted to leach lithium using organic acids and other leaching agents. In this study, selective leaching was performed using the organic acid methane sulfonic acid (MSA, CH₃SO₃H). Experiments were conducted to determine the optimal conditions for selectively leaching lithium by varying the MSA concentration, pulp density, and hydrogen peroxide dosage. The results of this study showed that lithium was leached at approximately 100%, while iron and phosphorus components were leached at about 1%, verifying the leaching efficiency and the leaching rates of the main components under different variables.

• The Journal of the Petrological Society of Korea
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• v.22 no.3
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• pp.219-233
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• 2013

Spherulitic rhyolite occur as part of ring dyke which showing a vertical flowage of $60^{\circ}{\sim}90^{\circ}$, of the Jangsan cauldron was studied. The spherulites range in diameter from a few millimeters to 2.8 centimeters or more, and average 5~10 millimeters. It belongs to radiated simple spherulite type. They consist of a core of moderate brown dense material encased by a thin crust, a few millimeters thick at most of white grey material. The spherulites frequently have a radiating fibrous structure, which are thought to have formed as a consequence of rapid mineral growth caused by very fast cooling of the dykes in shallow depth near the surface. EPMA examination of the concentric-zoned core of spherulites show that they are mainly composed of cryptocrystalline-fibrous intergrowth of silica minerals and alkali feldspars which have $SiO_2$ 82% or more, $Al_2O_3$ 7~10%, $Na_2O+K_2O$ less than 8%. The feldspar compositions of the spherulites lie essentially within the sanidine field. XRD examination show that spherulites are mainly composed of quartz, sanidine, albite with minor mica, kaolinite and chlorite. According to X-ray mapping, the spherulites are enriched in $SiO_2$ in the core and partly enriched $Na_2O$ or $K_2O$, $Al_2O_3$ in the shell that reflect in compositional zoning with increasing spherulitic devitrification. The feathery and non-equant crystal shapes of spherulites from rhyolite dyke of Jangsan cauldron suggest that they may have formed during the rapid cooling of dyke under the static state, or faster velocity of devitrification from glassy materials than movement velocity of the magma intrusion. The spherulitic rhyolite originated from high-silica(75.4~75.7 wt.%) rhyolite magma.

• Journal of the Society of Disaster Information
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• v.9 no.4
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• pp.449-461
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• 2013

As the hydrofluoric acid leak in Gumi-si, Gyeongsangbuk-do or hydrochloric acid leak in Ulsan, Gyeongsangnam-do demonstrated, chemical related accidents are mostly caused by large amounts of volatile toxic substances leaking due to the damages of storage tank or pipe lines of transporter. Safety assessment is the most important concern because such toxic material accidents cause human and material damages to the environment and atmosphere of the surrounding area. Therefore, in this study, a hydrofluoric acid leaked from a storage tank was selected as the study example to simulate the leaked substance diffusing into the atmosphere and result analysis was performed through the numerical Analysis and diffusion simulation of ALOHA(Areal Location of Hazardous Atmospheres). the results of a qualitative evaluation of HAZOP (Hazard Operability)was looked at to find that the flange leak, operation delay due to leakage of the valve and the hose, and toxic gas leak were danger factors. Possibility of fire from temperature, pressure and corrosion, nitrogen supply overpressure and toxic leak from internal corrosion of tank or pipe joints were also found to be high. ALOHA resulting effects were a little different depending on the input data of Dense Gas Model, however, the wind direction and speed, rather than atmospheric stability, played bigger role. Higher wind speed affected the diffusion of contaminant. In term of the diffusion concentration, both liquid and gas leaks resulted in almost the same $LC_{50}$ and ALOHA AEGL-3(Acute Exposure Guidline Level) values. Each scenarios showed almost identical results in ALOHA model. Therefore, a buffer distance of toxic gas can be determined by comparing the numerical analysis and the diffusion concentration to the IDLH(Immediately Dangerous to Life and Health). Such study will help perform the risk assessment of toxic leak more efficiently and be utilized in establishing community emergency response system properly.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.4
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• pp.10-20
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• 2014

This study was carried out for the purpose of analysis correlations between street furniture design elements and preference of street furniture. This research analyzed the various street furniture set on Ilsan new town street, which are rest, hygiene, light, information, sale, traffic, and landscape. This study has processed by analysing street furniture literature investigation and consideration of theory. First, for analysed effect of street furniture element, has been appear as element 'relaxation facilities', 'information facilities', landscape facilities' mainly effect on street. Specially, 'rest', 'landscape', 'information' in order had a major influence on scenery. Each kind of 'chair elements' in rest facilities, 'sign board' in information facilities, 'sculpture', 'fountain' in 'landscape facilities' has analyzed as the main elements in the landscape affinity property affecting factor. Second, the results of analyzed landscape elements (shape, colour, texture, scale) affect to the affinity of street furniture. chair which are included in rest facilities affect "texture", "form", "scale", "color" in the order of preference of the molding design elements that influence landscape. Particularly, showed statistically significant on 'colour' element affecting the landscape preference than the other three elements. It means as the chair element which is rest facilities mainly affect on preferences, rather than texture, form, scale, colour. Monument in the landscape associated with a preference 'colour', 'shape', 'texture' 'scale' and appears to be in order of impact so we could get the consequence like chair and rest facilities show different aspects of the respectively. It means, visual element which are colour and shape significantly impact on landscape preferences. Third, information facilities such as signboard formative elements of landscape design preferences and correlation with negative showed that the correlation. That mean if the sign board is very negative influence on landscape preferences and the correlations of the design formative elements appear in order of 'scale', 'colour', 'texture'. It also means that the 'scale' namely the size of advertising material and colour are adversely affected in terms of landscape. As these results, when design street furniture as the street scenery, facilities according to the kind of the shape element and need to focus on relative shape element according to the kind of facilities difference. Finally, so far as to clarify the street furniture, mainly 'function' and 'system' classification shows undesirable in outdoor scape. Thus, performed studies in relationship with landscape, classify 'kind of facilities' is more desirable than 'system'.

• Korean Journal of Soil Science and Fertilizer
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• v.18 no.2
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• pp.148-155
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• 1985

This study was conducted to find out the effect of rice straw and wollastonite applied to the paddy soil on the growth and yield of the rice plant. The soil was treated with two level of straw 0 and 88gr per pot, of which respectively combined with 4 levels of wollastonite, 0 (Avail $SiO_2$: 50 ppm), 27 (Avail. $SiO_2$: 150 ppm), 85 (Avail. $SiO_2$: 300 ppm) and 185 (Avail. $SiO_2$: 450 ppm) gr per pot. The results for two years experiment were as follows. 1. Application of rice straw and wollastonite, respectively, suppressed the growth of the plant at early stage. As a consequence the hight and number of tiller of the plant were comparatively smaller, but the combined effect of rice straw and wollastonite treatment on the plant growth appeared after the maximum tillering stage and got a better yield as compared with single treatment of rice straw or wollastonite. 2. At the pot of no rice straw and 27 gr wollastonite treatment, and also pot of rice straw and 85gr (in the year of 1983 experiment) as well as 135gr wollastonite treatment (in the year 1984 experiment), the yield of total dry material and unhulled rice of the plant were respectively higher than other pots in different treatment and the plant height showed similar tentency. Application of rice straw in paddy soil appeared to require more wollastonite for growth of the rice plant as compared with no rice straw application. 3. The highest yield was obtained at the pot with rice straw and 85gr of wollastonite treatment in the year of 1983 experiment, were its yield had 25% increament as compared with the control pot, while being studied for residual effect of rice straw and wollastonite application in the next year, the highest yield was obtained at the pot with rice straw and 135gr wollastonite treatment, where its yield had 30% increament as compared with the control pot.

• Journal of Chest Surgery
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• v.40 no.7 s.276
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• pp.480-484
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• 2007

Background: Major vascular injuries can jeopardize a patient's life or imperil limb survival. We performed this study to establish an optimal management plan for vascular injuries. Material and Method: We retrospectively reviewed 26 cases of vascular injury that were treated at Pusan National University Hospital from May, 1999 to September, 2004. The age and sex distribution, the locations and causes of vascular injury, the diagnostic tools, the degree of injuries, clinical manifestations, the treatment modality and complications were reviewed. Result: The mean age was 39.5 years (range: $12{\sim}86$) and the male to female ratio was 22 : 4. The injuries were in 6 descending thoracic aortas, 4 femoral arteries, 4 popliteal veins and so on. The causes of injury were iatrogenic in 8 cases, traffic accident in 7, stab injury in 6 and industrial accident in 5. The most commonly used diagnostic tools were CT and angiography. The degrees of arterial injury were pseudoaneurysm in 10 cases, partial severance in 5, complete severance in 3 and thrombosis in 3. The degrees of venous injury were partial severance in 6 cases, complete severance in 2 and arteriovenous fistula in 2. The clinical manifestations were absence of pulse in 8 cases, coldness in 7, chest pain in 6, swelling in 5, bleeding in 5 and so on. The most frequently used type of revascularization was graft interposition in 11 cases. Two arteriovenous fistulae were repaired by endovascular procedure. There was one case of mortality due to multi-organ failure after hemorrhagic shock, There were three major amputations, and two of them were due to delayed diagnosis and treatment. Conclusion: A system for the early diagnosis and treatment is essential for improving limb salvage and patient mortality. As a consequence of the widespread application of endovascular procedures, the incidence of iatrogenic injuries has recently increased. Educating physicians is important for the prevention of iatrogenic injury. Easy communication and cooperation for earlier involvement of a vascular surgeon is also an important factor.