• Elastomers and Composites
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• v.52 no.2
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• pp.114-130
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• 2017

Enhancing the properties of rubber, such as the tensile strength, modulus, and wear abrasion, by the addition of carbon black and silica as fillers is very important for improving the performance of rubber products. In this review, we summarize the general features of 'the reinforcement of rubber by fillers' and the equations for representing the reinforcement phenomena. The rubber reinforcement was attributed to enhancement of the following: the rubber, bound rubber, formation of networks, and combination between rubber chains and silica followed by entanglement. The reinforcement capability of silica species with different surface and networked states demonstrated the importance of the connection between the silica particles and the rubber chains in achieving high reinforcement. The model involving combination followed by entanglement can provide a plausible explanation of the reinforcement of rubber by carbon black and silica because the combination facilitates the concentration of rubber chains near the filler particles, and entanglement of the rubber chains around the filler particles enforces the resistance against deformation and breakage of rubber compounds, resulting in high reinforcement.

• KSBB Journal
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• v.20 no.6
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• pp.393-400
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• 2005

Hydrogen($H_2$) as a clean, and renewable energy carrier will be served an important role in the future energy economy. Several biological $H_2$ production processes are known and currently under development, ranging from direct bio-photolysis of water by green algae, indirect bio-photolysis by cyanobacteria including the separated two stage photolysis using the combination of green algae and photosynthetic microorganisms or green algae alone, dark anaerobic fermentation by fermentative bacteria, photo-fermentation by purple bacteria, and water gas shift reaction by photosynthetic or fermentative bacteria. In this paper, biological $H_2$ production processes, that are being explored in fundamental and applied research, are reviewed.

• Journal of the Korean Arthroscopy Society
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• v.6 no.1
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• pp.7-13
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• 2002

Purpose : Preliminary report of the technique and trial of double bundle PCL reconstruction using Achilles allograft. Materials and Methods : From May 1999 to July 2000, 8 cases of PCL insufficient patients were treated with Achilles allograft reconstruction using the double bundle and double femoral tunnel technique. The tibial tunnel was prepared anteromedially. All other combined injuries within the knees were treated accordingly. Minimal follow-up period was 1 year. The results was assessed from the point of function and stability using Lysholm knee score and KT-2000 arthrometer. Results : Up to present follow up. 8 patients showed good sign of recovery with no instability (translation less than 2 mm) except olio that has been grafted-ligament rupture. In addition, none showed any sign of infection nor ROM limitation. Two complications were seen, which one had grafted-bone fracture and the other grafted-ligament rupture. The former occurred during operation and the latter occurred due to improper protection. Conclusion : Presently the follow up period is too short to draw any conclusive opinion but it is essential to select healthy and well sterilized allografts fur successful outcome. Double femoral tunnel technique seems to be more physiologic in PCL reconstruction. With these prerequisites, it seems to be a good alternative to use Achilles allografts fur the reconstruction of PCL. However, a longer follow-up is needed.

• Journal of Korean Society of Forest Science
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• v.85 no.1
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• pp.96-106
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• 1996

Red alder(Alnus rubra Bong.) seedlings inoculated with Frankia only or both Frankia and spores of Alpova diplophloeus(Zeller & Dodge) Trappe & Smith were grown in a greenhouse for ten weeks. The ten-week-old seedlings were fertilized with six nitrogen(N) and phosphorus(P) fertility regimes (no fertilization, 10mM $NH_4NO_3$, 50mM $NH_4NO_3$, 5mM $KH_2PO_4$, 10mM $NH_4NO_3+5mM$ $KH_2PO_4$, and 50mM $NH_4NO_3+5mM$ $KH_2PO_4$) three times a week for ten weeks. The higher N-fertilization significantly increased mycorrhiza formation by greenhouse contaminant mycorrhizal fungi, but decreased N-fixation and P concentration in nodule tissues. P-fertilization significantly increased nodule and shoot dry weight, and P concentration in plant tissues. When N was highly fertilized, however, the P-fertilization effect disappeared in nodule P concentration but doubled in leaf P concentration. A. diplophloeus inoculation significantly increased diameter growth and $CO_2$ exchange rate, but decreased leaf dry weight. Our results suggest that the higher N- or P-fertilization affect nitrogenase activity and mycorrhizal development but the effects are changed by their interactions.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.5
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• pp.290-303
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• 2003

Modern agriculture has been heavily dependent on chemical fertilizers to meet the food demands of ever increasing population. Progressive depletion of major plant nutrients in soil due to intensive cultivation practices has also necessitated the use of higher dose of chemical fertilizers particularly in soils where the organic matter content is very low. Indiscriminate use of chemical fertilizers and pressure on agriculturists to enhance per area crop yields has led to fast depletion of fossil fuel resources with concomitant increase in the prices of chemical fertilizers and also led to environmental pollution. Hence, the current trend throughout the world is to explore the possibility of using alternate nutrient sources or increasing the efficiency of chemical fertilizers by supplementing them with organic fertilizers and bioinoculants comprising largely microbes like, bacteria, fungi, algae etc to enhance nitrogen and phosphates in the soil thus creating a sustainable agricultural environment. Among the different microbial inoculants or biofertilizers, Azospirillum could be a potential candidate due to its non specific host root colonization. It had the capability to fix $N_2$ in wide pH regimes and even in presence of combined nitrogen. Azospirillum inoculation can increase the crop yield to 10-25% and substitute 25% of recommended doses of nitrogenous fertilizers. Apart from nitrogen fixation, Azospirillum is also involved in the root improvement, the activity which was attributed to an increase in the rate of water and mineral uptake by roots. The ability of Azospirillum to produce phytohormones was reported to enhance the root respiration rate, metabolism and root proliferation. They have also been reported to produce polyhydroxybutyrate, that can be used as a biodegradable thermosplastic. A lot of studies have addressed improvements in enhancing its efficiency to fix nitrogen fixation and hormone production.

• Journal of Yeungnam Medical Science
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• v.7 no.1
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• pp.69-80
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• 1990

A clinical analysis was done on 23 patients(24 hips) with fracture of the femoral neck, who had been admitted and treated at our Orthopedic department during the period of 4 years, from Jan, 1984 to May 1988. The results were as follows : 1. 23 patients were comprised of 4 males and 19 females, and 11 patients were over 65 years old. 2. 18 cases of 24 cases were due to minor traumas such as slipping down, and for over 65 years old, all cases were due to simple minor traumas, 8 cases were showed a severe osteoporosis, below grade 3 of the Singh's index. 3. 14 cases of 24 cases were displaced subcapital fractures, and 6 cases displaced transcervical fractures. Only 4 cases were the undisplaced transcervical fractures. 4. In treatment of fractures internal fixations after manipulation were performed in 14 cases and primary arthroplasties in 10 cases. Secondary arthroplasties were done in complicated 4 cases of 14 cases treated with internal fixations. 5. Complications after internal fixation were developed in 7 cases out of 14 cases, avascular necrosis in 6, nonunions in 2, pin migrations in 3, and metal failure in 1 case. 6. In 14 arthroplasty immediate surgical fitness of femoral stem were related to late loosening of femoral stem(correlation coefficient r=-0.68, p<0.01).

• The Journal of the Convergence on Culture Technology
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• v.5 no.4
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• pp.277-282
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• 2019

This study analyzed the determinants of the financial Soundness of savings banks. In particular, empirical analysis was carried out on how the loan deposit ratio correlates with financial soundness after restructuring. As the restructuring of savings banks was finalized in 2014, asset management changed and it is time to analyze the financial characteristics of savings banks. In summary, the relationship between the savings bank lending rate and the NPL ratio is estimated to have a negative value at the 1% significance level. In other words, the higher the mortgage rate, the lower the substandard and below ratio. It can be said that it is not easy for a savings bank to build an aggressive loan portfolio. In other words, the more difficult it is to finance loans through savings deposits, the more likely the risk aversion tends to be. The higher the corporate loan ratio, average interest expense, and economic growth rate, the higher the risk index. The larger the asset size and the higher the loan growth rate, the lower the risk index. Increasing the mortgage rate may reduce risk-seeking behavior, but it does not mean that it is unconditionally positive for savings banks. Therefore, the loan deposit rate regulation should reduce the incentives for excessive asset expansion and manage preemptive soundness through lending portfolio management.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.6
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• pp.851-857
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• 2018

In this research, LCA analysis of the manufacturing process of pot bearing for fixed, movable in all directions, movable in one direction was carried out to analyze the environmental load using the LCA methodology. Especially, the water footprint that has been and issue in recent years was analyzed. As a result of LCA, it was analyzed that the contribution of the plate was more than 64.2% in all of the six impact categories in the case of fixed pot bearing base, and more than 94% in the category of resource depletion and photochemical oxidant creation. In the case of all direction pot bearing and one direction pot bearing, the contribution of PTFE was the highest in the global warming and stratospheric ozone depletion, and the contribution by the plate was higher in the other impact categories. The water footprint of each type of pot bearing was analyzed as $22.4m^3\;H_2O\;eq/kg$ for one direction pot bearing, $17.1m^3\;H_2O\;eq/kg$ for fixed pot bearing, and $14.1m^3\;H_2O\;eq/kg$ for all direction pot bearing. As a result of life cycle analysis, the contribution of water use in manufacturing was more than 65% in all three types. The results of this study can be used as basic data for decision making in construction method and material selection of bridges in the future.

• Journal of Veterinary Clinics
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• v.24 no.4
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• pp.631-635
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• 2007

Luxation of the hip is the most common luxation seen in small animals. Luxations are classified by the direction in which the femoral head lies in relation to the acetabulum and craniodorsal luxations are the most common type. Recommendations for treatment are based on the presence of preexisting disease, the type and duration of luxation and severity of concurrent injuries. In this study modified external skeletal fixation was used for craniodorsal coxofemoral luxation in 5 dogs. Luxated head Joint was reduced and fixator pins were applied into the greater trochanter, the middle point of iliac body and the lateral surface of sacroiliac joint in a closed fashion. Reduction was successful in 4 of the 5 operated limbs. Complications noted in this study included pin tract drainage, pin loosening and secondary fracture at the pin insertion site.

• The korean journal of orthodontics
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• v.40 no.2
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• pp.115-126
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• 2010

This case report describes the treatment of a 66 year old adult patient with a diagnosis of severe obstructive sleep apnea who was intolerant of nasal continuous positive airway pressure (nCPAP) treatment and oral appliance therapy. An alternative treatment of snoring and obstructive sleep apnea (OSA) with 2 orthodontic microimplants anchored to the mandible providing skeletal anchorage for mandibular advancement was implemented. After a 2 week healing period, a custom designed facemask provided extraoral anchorage to which the microimplants were connected to for titratable mandibular advancement. Microimplant Mandibular Advancement (MiMA) therapy resulted in resolution of the symptoms of severe OSA with a reduction of the apnea-hypopnea index (AHI), snoring and OSA symptoms.