• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.3
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• pp.318-325
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• 2014

The main object of this study is to investigate the collection characteristics of wet-type rotating porous disk system experimentally. The experiment is carried out to analyze the pressure drop and collection efficiency for the present system with the experimental parameters such as system inlet velocity, stage number, tube diameter, inlet concentration, etc. In results, for the present system, at 5 stage and ${\upsilon}_{in}=1.8m/s$, the pressure drop becomes significantly lower as $64mmH_2O$ in comparison with that of the conventional wet type scrubber (Venturi scrubber, over $250mmH_2O$). The collection efficiencies increase with higher inlet velocity showing 92, 95.7, 98.4%, while $SO_2$ removal efficiencies decrease with increment of inlet velocity as 80, 65, 50% at ${\upsilon}_{in}=1.08$, 1.44, 1.8 m/s and tube diameter $D_t=10mm$, respectively. The present system is to be considered as an effective compact system for a simultaneous removal of particle/gas phase pollutants from marine diesel engines.

• Journal of Biosystems Engineering
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• v.5 no.1
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• pp.1-14
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• 1980

Threshing operation may be one of the most important processes in the paddy post-production system as far as the grain loss and labor requirement are concerned . head-feeding type threshers commercially available now in Korea originally were developed for threshing dry paddy in the range of 15 to 17 % in wet basis. However, threshing wet-paddy with the grain moisture content above 20 % has been strongly recommended, especially for new high-yielding Indica -type varieties ; (1) to reduce high grain loss incurred due to the handling operations, and (2) to prevent the quantitative and qualitative loss of milled -rice when unthreshed grains are rewetted due to the rainfall. The objective of this study were to investigate the adaptability of both a head-feeding type thresher and a throw-in type thresher to wet-paddy , and to find out the possiblilities of improving the components of these threshers threshing. Four varieties, Suweon 264 and Milyang 24 as Tongil sister line varieties, minehikari and Jinhueng as Japonica-type varieties, were used at the different levels of the moisture content of grains. Both the feed rate and the cylinder speed were varied for each material and each machine. The thresher output quality , composition of tailing return, and separating loss were analyzed from the sampels taken at each treatment. A separate experiment for measurement opf the power requirement of the head-feeding type thresher was also performed. The results are summarized as follows : 1. There was a difference in the thresher output quality between rice varieties. In case of wet-paddy threshing at 550 rpm , grains with branchlet and torn heads for the Suweon 264 were 12 % and 7 % of the total output in weight, respectively, and for the Minehikari 4.5 % and 2 % respectively. In case of dry paddy threshing , those for the Suweon 264 were 8 % and 5% , and for the Minehikari 4% and 1% respectively. However, those for the Milyang 23 , which is highly susceptable to shattering, were much lower with 1 % and 0.5% respectively, regardless of the moisture content of the paddy. Therefore, it is desirable to breed rice varieties of the same physical properties as well as to improve a thresher adaptable to all the varieties. Torn heads, which increased with the moisture content of rall the varieties except the Milyang 23 , decreased as the cylinder speed increased, but grains with branchlet didnt decrease. The damaged kernels increased with the cylinder speed. 3. The thresher output quality was not affected much by the feed rate. But grains with branchlet and torn heads increased slightly with the feed rate for the head-feeding type thresher since higher resistance lowered at the cylinder speed. 4. In order to reduce grains with branchlet and torn heads in wet-paddy threshing , it is desirable to improve the head-feeding type thresher by developing a new type of cylinder which to not give excess impact on kernels or a concave which has differenct sizes of holes at different locations along the cylinder. 5. For the head-feeding type thresher, there was a difference in separating loss between the varieties. At the cylinder speed of 600 rpm the separating losses for the Minehikari and the Suweon 264 were 1.2% and 0.6% respectively. The separating loss of the head-feeding type thresher was not affected by the moisture content of paddy while that of the Mini-aged thresher increased with the moisture content. 6. From the analysis of the tailings return , to appeared that the tailings return mechanism didn't function properly because lots of single grains and rubbishes were unnecessarily returned. 7. Adding a vibrating sieve to the head-feeding type thresher could increase the efficiency of separation. Consequently , the tailing return mechanism would function properly since unnecessary return could be educed greatly. 8. The power required for the head-feeding type thresher was not affected by the moisture content of paddy, but the average power increased linearly with the feed rate. The power also increased with the cylinder speed.

• Journal of Nutrition and Health
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• v.25 no.6
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• pp.450-460
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• 1992

The study was performed to investigate the effect of corn bran as a fiber source on the utilization of thiamin niacin and pantothenic acid in human subjects for 8 weeks. Four different corn bran diets were fed : dry milled fine(DF) dry milled coarse(DC) wet milled fine(WF) and wet milled coarse(WC) Basal diet no corn bran bread added was employed as a control Apparent recovery of each B complex vitamin in urine was estimated to evaluate the vitamin and compared. The utilziation of three B vitamins was affected by the corn bran treatment. Dry milled corn bran had a higher recovery rate of thiamin(dry milled : 233% wet milled : 1.70%) than those receiving wet milled corn bran. Similar recovery pattern of niacin(dry milled : 1.94% wet milled : 1.50%) to that of thiamin was also observed. Particle size seemed to affect the vitamin utilization regardless of type of corn bran. Coarse bran gave a lower recovery value than fine corn bran in genreral. For pantothenic acid the recovery of the vitamin was affected to a greater extent by particle size of corn bran than by type of corn bran milling(fine: 60.22% coarse : 51.51%) Groups consuming wet milled corn bran\ulcorner(5`.57%) excreted more NDF than those fed dry milled corn bran(42.29%) Dry milled corn bran showed little or no water holding capacity poor fecal bulking properties and increased fecal transit time. The results suggest that corn bran supplementation exerts an negative effect on three B vitamin utilization.

• International Journal of Industrial Entomology and Biomaterials
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• v.16 no.2
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• pp.61-66
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• 2008

In this paper, the regenerated silk fibroin (SF)/nylon 6 blend filaments were fabricated using wet spinning technique and the effect of coagulant on the post drawing and morphology of blend filaments was investigated. In the result of wet spinnability, methanol, acetone, DMF, and THF showed relatively good coagulation strength and fiber formation for the regenerated SF. On the contrary, they did not exhibit strong enough to produce a uniform nylon 6 filament due to the lack of coagulation strength. In the examination of post drawing performance, methanol showed the highest maximum draw ratio of the blend filament over all blend ratios. The maximum draw ratio of SF/nylon 6 blend filaments decreased with the reduction of SF content regardless of type of coagulant. SEM observation showed the consistent result with that of post-drawing performance. As SF content decreased, the uniform and regular structure was changed to irregular one. In particular, the severe macro-phase separation between SF and nylon 6 could be detected in the 50/50 SF/nylon 6 blend filaments coagulated in methanol and THF.

• Journal of Welding and Joining
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• v.5 no.4
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• pp.28-35
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• 1987

The feasibility of underwater wet arc welding process is experimentally investigated by using high titanium oxide type electrodes and TMCP steel plates as base metal. It is assertained the tis process may be put to practical use. Main results are summarized as follows; (1) Sound underwater weld can be obtained by skilled welding operator, if proper welding conditions are selected. (2) In underwater wet arc welding process, the mechanical properties of HAZ are depend upon welding condition and the optimum welding condition can obtained. (3) The maximum hardness in the HAZ of TMCP steel plates is increased significantly in this welding process.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.3
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• pp.24-33
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• 2015

Linerboards containing wood flours were developed to increase solid contents in wet pressing process. Presence of wood flours in recycled fibers allowed passage of pressurized water at high wet pressing pressure, and increased solid contents while keeping the bulk of the board. The amount of wood flour addition should be controlled based on the intensity of the wet pressing pressure and the properties of the wood flours. Addition of cationic starch to the wood flour containing OCC furnish showed synergic increase of solid content and strength properties. Shapes of the wood flours such as spherical and rod type added to OCC furnish affected largely their solid content, drainage, and board physical properties.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.218-218
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• 2011

The CIGS Solar Cells have the highest conversion efficiency in the film-type solar cells. They consist of p-type CuInSe2 film and n-type ZnO film. The CdS films are used as buffer layer in the CIGS solar cells since remarkable difference in the lattice constant and energy band gap of two films. The CdS films are toxic and make harmful circumstances. The CdS films deposition process need wet process. In this works, we design and make the hitter and lamp reflection part in the sputtering system for the ZnS films deposition as buffer layer, not using wet process. Film thickness, SEM, and AFM are measured for the uniformity valuation of the ZnS films. We conclude the optimum deposition temperature for the films uniformity less than 1.6%. The ZnS films deposited by the sputtering system are more dense and uniform than the CdS films deposited by the Chemical Bath Deposition Method(CBD) for the CIGS Solar Cells.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.813-816
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• 2004

This study was performed to investigate bonding performance of epoxy resins for repairing of cracks in concrete, as a part of project to establish quality control standard for epoxy resins. In the slant shear strength test for hard and soft type epoxy, hard type was higher about 3 times than soft one. From the results, it is thought that hard type is suitable for load carrying. Injection of epoxy resin in the notch made flexural strength increase about $47\%$ over the specimen that epoxy resin is not injected. There were no differences in bonding performances with viscosity. Application of epoxy resin on the wet concrete surface made slant shear strength decrease about $46\%$, but similar performance to the case of application on the dry surface appeared by using epoxy resin for wet condition.

• Korean Journal of Metals and Materials
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• v.46 no.3
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• pp.169-173
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• 2008

Characteristics of etching and induced surface morphology variation by wet-etching of n-type GaN were investigated using phosphoric acidic solutions. Generally, the etch-rate was increased as the temperature of the etch solutions was increased, and the highest etch rate of about $300{\AA}/min$ was achieved at the temperature of $180^{\circ}C$. The morphology variation of the etched surface was observed by optical microscopy and atomic force microscopy. Initially, high density of hexagonal holes or pits were formed on the etched surface at the time of 40 min with the bimodal size of $20{\mu}m$ or $5{\mu}m$, respectively. However, as the etching time was increased further, the lateral size of the hexagonal holes or pits was increased, and finally, joined and merged together at the time of 100 min. This means that the etching of n-type GaN by phosphoric acidic solutions proceeded through the lateral widening and the merging of initial holes and pits.

• Journal of Korean Academy of Nursing
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• v.27 no.1
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• pp.96-108
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• 1997

The purpose of this study was to determine the effect of endurance training prior to occurrence of muscle atrophy on the mass, myofibrillar protein content and fiber crossectional area of atrophied hindlimb muscles of rats. Adult female Wistar rats were trained prior to occurrence of muscle atrophy induced by hindlimb suspension. Training began on the 1st day for 10min /day at 15m /min on a 0% grade, training exercise increased daily in time and intensity so that by the 4th week rats were running 60min /day, at 34m /min on a i3.5% grade. Wet weight and relative weight of soleus, plantaris and gastrocnemius muscle decreased significantly after seven days of hindlimb suspension. Wet weight and relative weight of soleus tended to increase and that of plantaris and gastrocnemius tended to decrease in the exercise group as compared to the control group. Myofibrillar protein content of soleus and gastrocnemius tended to increase and that of plantaris tended to decrease in the endurance trained group as compared to the control group. Fiber crossectional area of Type I, II fiber in soleus and plantaris muscle tended to increase in the exercise group as compared to the control group. Wet weight and relative weight of soleus. plantaris and gastrocnemius decreased significantly, myofibrillar protein content of soleus, plantaris and gastrocnemius increased in hindlimb suspended rats following endurance training as compared to the control group. There was no change in fiber type percentage and crossectional area of type I and II fiber in soleus muscle and that of type I and IIfiber in plantaris muscle decreased in the hindlimb suspended rats following endurance training as compared to the control group. Wet weight and relative weight of soleus and plantaris tended to increase, that of gastrocnemius increased significantly, myofibrillar protein content of soleus and plantaris muscle increased significantly and that of gastrocnemius tended to increase in the hindlimb suspended rats following endurance training as compared to sedentary rats following endurance training. Crossectional area of type I fiber of soleus muscle tended to increase. that of type I fiber of plantaris muscle increased significantly and that of type II fiber tended to increase in hindlimb suspended rats following endurance training as compared to sedentary rats following endurance training. The results suggest that endurance training prior to occurrence of muscle atrophy can attenuate the decrease of mass, myofibrillar protein content and fiber crossectional area induced by hindlimb suspension.