• Journal of Environmental Health Sciences
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• v.19 no.2
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• pp.23-33
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• 1993

The anaerobic digestion of organic synthetic wastewater in anaerobic fluidized bed bioreactor (AFBBR) and anaerobic fluidized packed bed bioreactor (AFPBBR) was studied. This study was conducted to evaluate efficiency and reliability of two reactor. Experiment was performed to find the effect of upflow rate with AFBBR and the height of packed bed with AFPBBR. As a result, this program obtained several conclusion. These are given as follows: As applied the upflow rate increased in AFBBR the produced volume of biogas increased, while the gas production and COD removal decreased at above 0.3 m$^3$/h. When a upflow rate is 0.4 m$^3$/h in AFBBR the volatile suspended solid (VSS) became significantly increased. At an organic loading rate from 0.1 to 0.4 of upflow rate in AFBBR, the methane yield was 1.5584 m$^3$CH$_4$/kgCOD removed, and the observed cell yield coefficient was 0.0933 gVSS/gCOD. In case of AFPBBR, the results showed also that 20 cm of height of packed bed was superior to other in the aspect ot biogas production, the content of methane and COD removal. At 20 cm of height, the profile of microorganisms was stable, while at 30 cm the VSS of effluent became higher than AFBBR. Though COD removal of AFPBBR increased with packed bed, COD removal deteriorate with over packing because the loss of pressure became higher in the reactor. At an organic loading rate from 20 to 40 cm of packed bed in-AFPBBR, the methane yield was 2.5649 m$^3$CH$_4$/kgCOD removed, and the observed cell yield coefficient was 0.0506 gVSS/gCOD. Based upon the results obtained, it is suggested that AFBBR and AFPBBR is the most effective conditions at 0.3 m3/h of upflow rate, the 20cm of packed bed, respectively. The rate constant are summarized as follow:

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.12
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• pp.1619-1625
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• 2011

The objective of this study determine the molding conditions of a double-shot injection mold for fabricating a computer mouse using different materials, by performing three-dimensional injection molding analysis. In order to select the optical injection molding conditions, the effects of the injection time, the maximum injection pressure, the effect of packing time on the injection molding characteristics, and the product qualities were quantitatively examined. From the results of the injection molding analysis, the optimal injection molding conditions of the double-shot injection mold, which leads the molded product to the minimized shrinkage and deflection, were estimated. The results of the injection molding experiments, showed that an appropriate computer mouse can be fabricated using different materials when the identified optimal injection molding conditions are adopted.

• Carbon letters
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• v.8 no.4
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• pp.326-334
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• 2007

In this study, graphite composites were fabricated by warm press molding method to realize commercialization of PEM fuel cells. Graphite composites have been considered as alternative economic materials for bipolar plate of PEM fuel cells. Graphite powder that enables to provide electrical conductivity was selected as the main substance. The graphite powder was mixed with phenolic resin and the mixture was pressed using a warm press method. First of all, the graphite powder was pulverized with a ball mill for the dense packing of composite. As the ball milling time increases, the average size of particles decreases and the size distribution becomes narrow. This allows for improvement of the uniformity of graphite composite. However, the surface electrical resistivity of graphite composite increases as the ball milling time increases. It is due to that graphite particles with amorphous phase are generated on the surface due to the friction and collision of particles during pulverizing. We found that the contact electrical resistivity of graphite particles increases as the particle size decreases. The contact electrical resistivity of graphite powders was reduced due to high molding pressure by warm press molding. This leads to improvement of the mechanical properties of graphite composite. Hydrogen gas impermeability was measured with the graphite composite, showing a possibility of the application for bipolar plate in fuel cell. And, I-V curves of the graphite composite bipolar plate exhibit a similar performance to the graphite bipolar plate.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.3
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• pp.195-199
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• 2013

Pseudoaneurysms are rare complications of orgthognathic surgery, trauma or other surgical procedures in the head and neck regions. Surgical approach is a routine procedure of bleeding control. However, bleeding control using angiography and embolization can also be an excellent method. We experienced pseudoaneurysm of the inferior alveolar artery occurring after surgical curettage of cystic lesion. The 33-year-old man who underwent surgical curettage of keratocystic odontogenic tumor was presented with severe bleeding in the right mandible ramal inner surface 14 days after the surgical curettage. After hemostasis with vaseline gauze packing and pressure, bleeding temporarily stopped. However, bleeding started after 14 days and soon it has been continued. Finally, the patient was diagnosed as pseudoaneurysm of the inferior alveolar artery from the enhanced-computed tomography images, and angiographic embolization was performed successfully. We report a rare case of pseudoaneurysm of the inferior alveolar artery after benign tumor curettage and review of the previewer's literature.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.44 no.3
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• pp.1-8
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• 2012

The effects of several factors including organic pigment blending and calending conditions on the surface and optical properties of coated paper were investigated. When clay and calcium carbonate are blended in the ratio of 7 to 3, highest smoothness and relative sediment volume were obtained. When organic pigments were added to the mixture of clay and calcium carbonate, the relative sediment volume did not changed significantly. However, when organic pigments were added to calcium carbonate, sheet gloss and smoothness were improved, and showed the better results than that obtained from the mixture of organic pigment and clay. When organic pigment is blended with clay, the particles of organic pigment are buried in the packing structure of coating layer. However, the particle shape of calcium carbonate is quite different from that of clay, and the aspect ratio of calcium carbonate is similar to that of organic pigment. Thus organic pigment particles are not buried and improved effectively the physical characteristics of coating layer. When the hollow sphere pigment was blended, opacity and sheet gloss were improved significantly. Even though the coating color applied was reduced, the similar level of opacity was maintained. Also, if particle size and void volume are increased, gloss is improved, because coating layer is easily transformed in calendering. Therefore, even though lower pressure was applied during calendering, the smoothness of surface of coating layer was improved, and the decrease of void volume in coating layer was reduced, and the quality of coated sheet can be improved.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.6
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• pp.613-619
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• 2016

A pneumatic control valve performs a major role in controlling the flow of a system or the level of a key tank in many power plants, and its performance should be guaranteed during the plant's lifetime. Its operation starts by supplying air to the pneumatic actuator or by exhausting the air from the actuator. To control the valve position, the amount of air supply or exhaust is adjusted by a control loop where various accessaries are equipped. In this paper, air leakage in the air supply line, changes in the valve packing force, and false adjustments of zero and the span of the positioner are simulated and analyzed using a 2-in pneumatic valve with a position control loop including an I/P converter and positioner, where the valve position is controlled within ${\pm}2%$ of the control pressure at 67% opening position.

• Agribusiness and Information Management
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• v.8 no.1
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• pp.1-10
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• 2016

Information and communication technologies (ICTs) have always mattered in agriculture too. In day-to-day practices of agriculture and allied sectors, the farmers often share their information. Changing weather patterns, soil conditions, pests and diseases always throw challenges to small and marginal farmers. So, the farmer needs up-dated information to cope with and even benefit from these changes. In the developing countries like India, where agriculture still plays a crucial role (over 58% of the rural households depend on agriculture as their livelihood) and the rising population from 1027 million to 1419 million during 2001-16 (a total rise of 38 percent or 1.3 percent per year) pose a lot of pressure on land and other resources to meet the food security needs on one hand and to meet the challenges of globalization on the other. Understanding and addressing these challenges are very crucial, in which ICT can play a major role. With the booming mobile, wireless, and Internet industries, ICT has found a foothold even in poor marginal and smallholder farms and in their activities. The survey conducted among the 120 farmers in Srikakulam district in India revealed that, ICT has revolutionized the agriculture in the modern days. Production and marketing information is accessed by 91% of the sample farmers through mobile in 2015, where it was only 5% in 2005. The extent of use of mobile phones by the farmers varied with the decision to be taken by them like Harvesting, packing, and storing (94%), Selling Decision (91%), Seed purchase (89%), Application of fertilizers and pesticides (88%) and Land preparation and planting (84%), other package of practices (77%). The farmers further opined that, 'Voice' was the dominating source of communication (96%) compared to Short Message Service (SMS) (only 27%) and Internet access (10%), as majority are illiterate. The use of camera (71%), Bluetooth (33%), Radio (61%) TV (41%) are the other means of sharing the information. In this context of importance of ICTs in Indian agriculture, greater attention justifies about the applications of ICT's to alleviate poverty and promote economic growth of the farming population.

• Korean Journal of Acupuncture
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• v.22 no.2
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• pp.127-149
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• 2005

This study is designed to investigate the method of manufacturing herbal acupuncture through literature of oriental medicine. The findings of this study are as follows; 1. The methods of manufacturing herbal acupuncture go through the process of abstraction, purification, mixing, filtration, putting and tight sealing in the container, sterilization, quality control, printing and packing 2. There are many ways to manufacturing herbal acupuncture, for example water-alcohol precipitation, alcohol-water precipitation, liquid-liquid abstract, acid-base abstract, metal base precipitation, distillation, molecular structure, polyamide absorption, dialysis, and ion exchange, etc. And popular method is water-alcohol precipitation. This is through alcohol precipitate extracting the principal ingredients from water abstraction. This is very simple and efficient way using melting characteristics of compounds in herb to water and ethanol. 3. Sterilization of herbal acupuncture is through heating-pressure, boiling, steam flowing, low temperature, filtering, radiation, cooling, and microwaves. Nowadays filtering is commonly used. And sterilization is estimated by an examination of asepsis . 4. Herbal acupuncture must be undergo study and experiment to clinical use. The problems of herbal acupuncture are turbidity, instability, causing hemolysis, pain, and fever. So many provisions (addition, sterilization, and filtration etc.) must be prepared. 5. The theory of manufacturing herbal acupuncture is from oriental medicine, not western. So it must be corresponded to oriental medical theory, for example Gimi(氣味), Guigyung(歸經), Ingyung(引經), Bosa(補瀉), and Match of Herb. It is recommended that further study of many other sided investigations in the future.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.1
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• pp.1-9
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• 1998

This study was designed to determine the most suitable manufacturing conditions of stewed pumpkin juice(SPJ) in terms of nutrition and taste. Well ripened pumpkin was heated for 3, 4, 5, 6 and 7 hours in a pressure cooker and then extracted and packed in retort pouches. These were kept at 4$^{\circ}C$ and 28$^{\circ}C$ for 30 days, respectively and changes of the physicochemical components of SPJ were investigated. The free amino acid compositions of pumpkin and SPJ occupied asparagine, aspartic acid, glutamine, arginine and serine in increasing order of abundance. Except SPJ heated for 3 hours, SPJ stored at 28$^{\circ}C$ had the most abundant free amino acids, followed by SPJ stored at 4$^{\circ}C$, and SPJ not stored. The fatty acid composition of pumpkin occupied behenic acid, erucic acid, palmitic acid, linoleic acid, heneicosanoic aicd, in order of abundance. When SPJ was heated over 3 hours, palmitic acid and linolenic acid decreased greatly. SPJ stored at 4$^{\circ}C$ and 28$^{\circ}C$ increased contents of saturated fatty acids such as behenic acid, palmitic acid than SPJ not stored. As SPJ was heated for a long time, carotenoid was mostly destroyed and the Hunter "L", "a" and "b" values of SPJ decreased. Among the mineral constituents of SPJ, Na and Ca were dominantly occupied. It was found that the range of the total visible cell count was 3~4CFU/ml from the SPJ which was heated for 3 hours and it increased by 1$\times$109CFU/ml when the SPJ was stored at 28$^{\circ}C$. It seems that the contamination by microorganism have occurred at packing process. In sensory evaluation, the SPJ which was heated for 5 hours had the highest scores in overall preference, sweet smell and sweetness.ce, sweet smell and sweetness.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.6
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• pp.117-124
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• 2017

In this study, we investigated the optimization of process conditions by using the Six Sigma process, design of experiment (DOE) method and response surface method (RSM) to resolve dimensional deviation and appearance problems arising from the shortened process time of the mobile phone rear cover. The analysis of the trivial many was performed by 2-sample T-test and cooling time, and mold temperature and packing pressure were selected as the vital fews affecting the overall width of the product. The optimal conditions of the process were then studied using the DOE and the RSM. We analyzed the improvement effects by applying the selected optimal conditions to the production process and the results showed that the difference between the mean value and target value of the overall width stood at 0.01 mm, an improvement of 88.89% compared to current process that fell within the range of standard dimension. The short-term process capability stood at $4.77{\sigma}$, which implied an excellent technology level despite a decrease by $0.22{\sigma}$ compared to the current process. The difference in process capability decreased by $2.44{\sigma}$ to $0.41{\sigma}$, showing a significant improvement in management capability. Ultimately, the process time of the product was shortened from 18.3 seconds in the current process to 13.65 seconds, resulting in a 34.07% improvement in production yield.