• Journal of Fisheries and Marine Sciences Education
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• v.24 no.5
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• pp.609-615
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• 2012

A histo-pathogical examination was carried out to evaluate the effect of commercial extruded pellet (EP) and a raw fish moist pellet (MP) diet on the health of juvenile rockfish cultured in marine net-cage for 7 months. Fish were distributed randomly to each net cage as a group of 76,000 fish (initial mean body weight 5.9 g). After 2 months, the hypertrophy or swelling of liver parenchymal cells was identified in most individuals and lasted until 7 months. Livers in EP fed group frequently showed hypertrophic parenchyma and fatty change with occasional atrophic cells. However, after 4 months, lymphocytic infiltration in splenic parenchyma was seen in a number of individuals. In addition, the gastric glandular epithelium was atrophied and in the lumen of renal tubules protozoan parasites were frequently identified but there was no correlation with the type of feed. Moreover, juvenile rockfish on EP diet showed gross and microscopic hypertrophy of the liver which would be due to oversupply of feed. Severe hepatic cellular hypertrophy or swelling could lead to the damage of microcirculation. Especially fatty change and atrophic change of liver could be the result from the damage, which could be responsible for immunological problem. Lymphocytic infiltration of spleen on the MP diet suggests that juvenile rockfish could be frequently exposed to infectious antigens.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.273-276
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• 2002

The fiber formation of conventional melt spinning is extruded by forcing the polymer melt through a spinneret by pumping mechanism usually involving high pressure. This is followed by cooling, solidification and appropriate drawing of the fiber. The spinning process is broadly applicable to polyolefin, polyamide, polyester and indeed the whole range of fibers forming thermoplastic polymers. (omitted)

• Journal of Microbiology and Biotechnology
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• v.9 no.1
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• pp.1-8
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• 1999

Most carbohydrates exist in nature in an insoluble state, which reduces their susceptibility towards various carbohydrases. Accordingly, they require intensive pretreatment for structural modification to enhance an enzyme reaction. The direct conversion of insoluble carbohydrates has distinct advantages for special types of reaction, especially exo-type carbohydrase; however, its application is limited due to structural constraints. This paper introduces two novel heterogeneous enzyme reaction systems for direct conversion of insoluble carbohydrates; one is an attrition coupled enzyme reaction system containing attrition-milling media for enhancing the enzyme reaction, and the other is a heterogeneous enzyme reaction system using extruded starch as an insoluble substrate. The direct conversion of typically insoluble carbohydrates, including cellulose, starch, and chitin with their corresponding carbohydrases, including cellulase, amylase, chitinase, and cyclodextrin glucanotransferase, was carried out using two proposed enzyme reaction systems. The conceptual features of the systems, their reaction characteristics and mechanism, and the industrial applications of the various carbohydrates are analyzed in this review.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1555-1560
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• 2000

Recently, optical pickup actuators have been designed to have structures that extruded lens to decrease their height, because they are used in very thin drive for notebook computers. However, because of discordant and undesirable of forces that are supposed to happen in this design feature, subsidiary resonance such as rolling and pitching mode exert bad influence on actuator. In this paper, we presented force constituents to clarify the cause of subsidiary resonance and proposed new finite element analysis method to calculate force precisely, and performed frequency response analysis to evaluate characteristics of actuators. As a result, we could find out design parameters to diminish the influence of subsidiary resonance. Sample actuators designed with appropriate parameters were fabricated and put to practical tests. Comparing analysis with experimental results, we verified the accuracy of the analysis and the effectiveness of the method presented.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.6
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• pp.152-157
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• 2012

This study investigates compressive strength of ice pellet strip which is potential medium for Natural Gas Hydrate(NGH) extruded from die holes of Twin-roll Press for Continuous Pelletizing(TPCP). Recently, the prototype of TPCP is newly developed where ice powder is continuously fed and extruded into strip-type pellet between twin rolls. The system is specifically designed for future expansion towards mass-production of ice pellet strips or solid form of natural gas hydrate. It is shown that the compressive strength of pellet strip heavily depends on factors in extrusion process such as disk size, surface smoothness, ring size, taper shape, feeding mechanism, and rotational speed. Here, the mechanism of TPCP, along with compressive strength of pellets is discussed in terms of its feasibility for producing NGH pellets in the future.

• Journal of the Korean Institute of Rural Architecture
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• v.20 no.4
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• pp.65-75
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• 2018

This thesis attempts to investigate and analyse the architectural characteristics of catholic churches in Gangwon province built in the 1950s. Catholic churches built at that time in Korea had many similarities basically since they were supported by UN forces after the Korean War and were established by priests connected to the Missionary Society of St. Columban. The results of study are as follows. In location, Except one catholic church, the catholic churches preferred low and gentle hill. In layout axis, catholic churches at Youngseo area preferred the north-south layout axis, whereas those at Youngdong favor the east-west layout axis. In approach, most of catholic churches around the Youngseo and Youngdong areas preferred entering the front entrance with a bell tower, whereas three of them at Youngdong did entering the front entrance with a bell tower around the rear corner. In floor plan, catholic churches at Youngseo preferred symmetry, whereas those at Youngdong preferred asymmetry. And every floor plan of catholic churches is rectangular type with transepts except one semicircular type. In apse shape, catholic churches in the Youngseo area preferred non-extruded types like a straight wall, whereas those in Youngdong have extruded types. Every catholic churches have no crypt under ground except one at Gangreung. Except one at Sokcho, every catholic church in this study has choir space in half story.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.2
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• pp.119-126
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• 2016

In this study we investigated the effects of symmetrically arranged heat sources on the heat release performances of extruded-type heat sinks through experiments and thermal fluid simulations. Also, based on the results we suggested a high-efficiency and cost-effective heat sink for a solar inverter cooling system. In this parametric study, the temperatures between heaters on the base plate and the heat release rates were investigated with respect to the arrangements of heat sources and amounts of heat input. Based on the results we believe that the use of both sides of the heat sink is the preferred method for releasing the heat from the heat source to the ambient environment rather than the use of a single side of the heat sink. Also from the results, it is believed that the symmetric arrangement of the heat sources is recommended to achieve a higher rate of heat transfer. From the results of the thermal fluid simulation, it was possible to confirm the qualitative agreement with the experimental results. Finally, quantitative comparison with respect to mass flow rates, heat inputs, and arrangements of the heat source was also performed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.4749-4755
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• 2014

In this study, to maximize the heat release from the heat generating environment, such as a high-capacity inverter, the heat release performance of the extruded-type heat sinks with the variation of the base thickness were investigated using the experimental and numerical methods. The base thickness was varied from 5 to 14 mm. The heat release was characterized by the amount of heat released through the heat sink, the surface temperature of heat sink base between the heat sources, and temperature of heat sources. The surface temperatures between heat sources and the amounts of heat release were improved more as the base thickness was decreased. In contrast, the temperatures of the heat sources decreased with increasing base thickness. Based on the case study of these heat sinks, it is believed that a heat sink with a 9.5mm-thick base was optimized for the heat release.

• Journal of Korea Foundry Society
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• v.33 no.4
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• pp.157-161
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• 2013

A ribbon-type polycrystalline silicon wafer was directly fabricated from liquid silicon via a novel technique for both a fast growth rate and large grain size by exploiting gas pressure. Effects of processing parameters such as moving speed of a dummy bar and the length of the solidification zone on continuous casting of the silicon wafer were investigated. Silicon melt extruded from the growth region in the case of a solidification zone with a length of 1cm due to incomplete solidification. In case of a solidification zone wieh a length of 2 cm, on the other hand, continuous casting of the wafer was impossible due to the volume expansion of silicon derived from the liquid-solid transformation in solidification zone. Consequently, the optimal length of the solidification zone was 1.5 cm for maintaining the position of the solid-liquid interface in the solidification zone. The silicon wafer could be continuously casted when the moving speed of the dummy bar was 6 cm/min, but liquid silicon extruded from the growth region without solidification when the moving speed of the dummy bar was ${\geq}$ 9 cm/min. This was due to a shift of the position of the solid-liquid interface from the solidification zone to the moving area. The present study reports experimental findings on a new direct growth system for obtaining silicon wafers with both high quality and productivity, as a candidate for an alternate route for the fabrication of ribbon-type silicon wafers.

• Animal Bioscience
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• v.37 no.6
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• pp.1085-1095
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• 2024

Objective: The main objective of this study was to determine available energy and nutritional digestibility of extruded cereals and the effect of extrusion on the nutritional value of feed ingredients, aiming to provide scientific basis for efficient application of extrusion in the diets of growing pigs. Methods: In Exp. 1, 48 crossbred growing pigs (Duroc×Landrace×Yorkshire) with an initial body weight (BW) of 34.6±2.2 kg were selected and fed with eight diets (non-extrusion or extrusion) to determine the digestible energy (DE), metabolizable energy (ME), and nutrients digestibility. Eight diets included extruded grains (barley, wheat, sorghum, or broken rice), while four had unprocessed grains. In Exp. 2, 9 diets were formulated including 4 cereals with extrusion or non-extrusion and a N-free diet. In addition, 9 growing pigs (BW = 22.3±2.8 kg) were fitted with T-cannula in the distal ileum and arranged in a 9×6 Youden square design. Results: Results show that apparent total tract digestibility of gross energy, dry matter, organic meal, ether extract, neutral and acid detergent fiber was not affected by the extrusion process and there was no interaction between cereal type and extrusion treatment on DE, ME. However, the apparent total tract digestibility for crude protein (CP) increased markedly (p<0.05). The standardized ileal digestibility (SID) of all amino acids (AA) except for leucine remarkably increased by extrusion (p<0.05). There was an interaction on the SID of arginine, leucine, isoleucine, methionine, phenylalanine, cystine, and tyrosine in growing pigs between type of grain and extrusion treatment (p<0.05). Conclusion: Extrusion increased the ileal digestibility of CP and most AA in cereals, however, the DE and ME of cereals were not affected in growing pigs.