• Parasites, Hosts and Diseases
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• 제54권4호
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• pp.537-541
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• 2016

Stellantchasmus falcatus (Digenea: Heterophyidae) is first reported from Cambodia through recovery of the metacercariae from mullet fish and adult flukes from an experimentally infected hamster. We purchased 7 mullets, Chelon macrolepis, in a local market of Phnom Penh, Cambodia, and each of them was examined by the artificial digestion method on May 2010. The metacercariae of S. falcatus were detected in all mullets (100%) examined, and their average density was 177 per fish. They were elliptical, $220{\times}168{\mu}m$ in average size. They were orally infected to an hamster to obtain adult flukes. Adults recovered at day 10 post infection were observed with a light microscope and a scanning electron microscope (SEM). They were small, $450{\times}237{\mu}m$ in average size, had a small oral sucker ($41{\times}50{\mu}m$), subglobular pharynx ($29{\times}21{\mu}m$), slender esophagus ($57{\mu}m$), long and thick-walled expulsor ($119{\times}32{\mu}m$), spherical ovary ($58{\times}69{\mu}m$), and 2 ovoid testes (right: $117{\times}74{\mu}m$; left: $114{\times}63{\mu}m$). Eggs were small, yellow, and $23{\times}12{\mu}m$ in average size. In SEM observations, tegumental spines were densely distributed on the whole tegument, and single small type I sensory papillae were distributed around the lip of oral sucker. The small ventral sucker was dextrally located and had 8 type I sensory papillae on the left margin. It has been first confirmed in the present study that the mullet, C. macrolepis, is playing the role of a second intermediate host of S. falcatus in Cambodia.

• Journal of Advanced Marine Engineering and Technology
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• 제21권1호
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• pp.82-87
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• 1997

This paper presents a method about the modeling of the medium - small diesel engine for the speed control and designs the robust speed control system by the $\mu$-synthesis, which has good performance, in spite of the existence of model uncertainities and the external disturbance. We confirmed the validity of the proposed modeling method and the designed control system by $\mu$-synthesis through the experimental responses.

• 한국식품과학회지
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• 제21권4호
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• pp.528-535
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• 1989

감자(세풍과 대지)에서 분리한 전분을 큰 입자와 작은 입자로 분획하고 입자별 일반성질과 호화특성을 비교하였다. 전분입자의 크기는 세풍전분이 $10{\sim}85{\mu}m$, 대지전분이 $13{\sim}90{\mu}m$이었고, 작은 입자$(<30{\mu}m)$는 대지전분이, 큰 입자$(>41{\mu}m)$는 세풍전분이 많았다. 일반성질과 물결합 능력은 차이가 없었고, 아밀로오스 함량은 큰 입자가 높았다. 팽윤력은 큰 입자가 작은 입자보다 낮았고, 아밀로그램의 최고점도는 세풍전분은 입자별로 차이가 없었으나, 대지전분은 큰 입자가 높은 값을 보였다. 호화온도 범위는 작은 입자가 큰 입자보다 넓었으나, 호화 엔탈피는 차이를 보이지 않았다. 두 전분 모두 입자별에 관계없이 $70^{\circ}C$에서 호화가 완료되었다.

• 정보저장시스템학회논문집
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• 제1권2호
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• pp.188-191
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• 2005

Two different coverlayers which is useful for an optical buffer and a mechanical protection made of not only UV resin but also polycarbonate coversheet were prepared on small form factor optical disks. Thin coverlayer of 10 ${\mu}m$ and thick coverlayer of 80 ${\mu}m$ were fabricated. 10 ${\mu}m$-thick coverlayer was coated using UV resin material by spin coating method for the flying optical head application. On the other hand, 80 ${\mu}m$-thick coverlayer using coversheet with the resin bonding material was prepared for the non-flying optical head application. Both cases, the thickness uniformity seem to be the primary prerequisite factor, and it was analyzed. Thickness of 10 ${\mu}m$-thick UV resin coverlayer could be controlled within ${\pm}0.2m$ range and 80 ${\mu}m$-thick coversheet could be controlled within ${\pm}3{\mu}m$ range. However, the yield of such thickness tolerance was not good. New design of metal housing holder and polycarbonate outer ring was adopted to diminish the ski-jump phenomenon. Specifically, the polycarbonate outer ring was very effective to reduce the ski-jump. However, it should be careful to maintain uniform edge between disk and ring for the perfect coverlayer.

• 한국식품과학회지
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• 제21권1호
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• pp.52-57
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• 1989

보리 전분입을 구성하는 대입자와 소입자의 물리, 화학적 차이에 관해서 비교하였다. 대입자의 직경은 약 $28-30{\mu}m$이고. 소입자는 약 $6{\mu}m$ 이었으며, Hiproly 전분 입자의 수에 대한 소입자의 수는 95%정도 이었다. 아밀로오즈의 함량은 대입자가 소입자 보다 높게 나타났다. 아밀로오즈의 분자 형태에 관한 대입자 소입자 전분의 고찰로써, iso-amylase처리 전분의 구성성분의 차이, X선 회절도의 차이, 호화특성, 산분해성 등의 검토에 의하면, 아밀로펙틴의 미세결정 구조인 망상구조상에 있어서 대입자와 소입자가 서로 다른 구조를 하고 있으리라 예측된다.

• 한국재료학회지
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• 제23권1호
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• pp.13-17
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• 2013

The alignments of polystyrene particles of $1{\mu}m$ and $5{\mu}m$ sizes in an aqueous colloidal system were observed by varying the electric field strength, the frequency and the water flow. Spherical mono-dispersed polystyrene particles dispersed in pure water were put into a perfusion chamber; an AC electric field was applied to the Au/Cr electrodes with a 4 mm gap on the glass substrate. The mixture of the $1{\mu}m$ and $5{\mu}m$ sized polystyrene particles at 0.5 vol% concentrations for each size was set in the dielectrophoresis conditions of 1 kHz and 150 V/cm. Large particles of $5{\mu}m$ size were aligned to form chains as the result of the dielectrophoresis force interaction. On the contrary, small particles of $1{\mu}m$ size did not form chains because the dielectrophoresis force was not sufficiently large. When the electric field increased to 250 V/cm, small particles were able to form chains. After the chains were formed from both large and small particles, they began to coalescence as time passed. Owing to the electroosmotic flow of water, wave patterns along the perpendicular direction of the applied electric field appeared at the conditions of 200 Hz and 50 V/cm, when the dielectrophoresis force was small. This wave pattern also appeared for small particles at 1 kHz and 150 V/cm conditions due to the flow of solvent when water was forced to circulate.

• 한국식품조리과학회지
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• 제32권2호
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• pp.197-203
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• 2016

Purpose: In this study, small black beans (Rhynchosia nulubilis) that were produced in the Jungsun province of South Korea were selected for use in various cooking recipes because they are known to contain higher isoflavones and excellent antioxidant effects, as compared to any other domestic soybeans. Methods: Physicochemical and antioxidant characteristics of small black beans were analyzed with uncooked beans and four other cooking methods of pan broiling, boiling, steaming, and pressure cooking. Results: Contents of ${\beta}$-glucosides (daidzin, glycitin, and genistin) and aglycone (daidzein, glycitein, and genistein) in small black beans were significantly different depending on the cooking methods (p<0.001). The results of the experiment indicated that the amount of total polyphenol in pressure cooked beans was highest, showing a value of 7.16 mg/g (p<0.001). Most contents of isoflavones (${\beta}$-glucoside, aglycone) in uncooked beans appeared to increase after cooking. In particular, the amount of glycitein was highest in pan broiled beans ($9.63{\mu}g/g$). The total isoflavone content differed among the different cooking methods, ranging from highest to lowest in the following order : pan broiled beans ($759.49{\mu}g/g$), pressure cooked beans ($725.12{\mu}g/g$), boiled beans ($591.05{\mu}g/g$), steamed beans ($511.61{\mu}g/g$), and uncooked beans ($180.80{\mu}g/g$) (p<0.001). Conclusion: Especially, the amount of isoflavones increased significantly in pan broiled beans and pressure cooked beans, suggestive of optimized cooking methods for increasing nutritional and functional contents in cooked food.

• Applied Microscopy
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• 제18권2호
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• pp.167-176
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• 1988

Extrachromosomal circular DNA complexes from erythrocytes and splenocytes isolated from Carassius carassius were examined by mica-press-absorption method. The method was described that released small polydisperse circular DNA molecules in situ from the erythrocytes and the splenocytes and that allows selective observation of the small circular DNA complexes bound to cellular components. The released polydisperse circular DNA complexes were absorbed preferentially on mica in a divalent cation-free medium then processed for electron microscopy. Small circular DNAs showed a heterogeneous size distribution of $2{\sim}10{\mu}m$ with a mean contour length of $4.3{\mu}m$ for the circulating erythrocytes and that of $0.7{\sim}3.6{\mu}m$ with a mean contour of length $2.04{\mu}m$ for the splencytes. Cells contained $100{\sim}300$ copies and $300{\sim}700$ copies obtained from the erythrocytes and the splenocytes, repectively. Possible biological functional implications for size distribution of extrachromosomal circular DNAs are discussed.

• 한국안전학회지
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• 제34권3호
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• pp.28-35
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• 2019

Dry water is a core-shell structured powder which comprises a very fine water core covered with hydrophobic silica particles. Recently, the dry water has attracted attention as a new type of fire extinguishing agents. However, characteristics of the dry water as a fire extinguishing agent have not been revealed until now. To our best knowledge, this is the first work to uncover effects of particle size of the dry water on the fire extinguishing performance. Pristine dry water, which has heterogeneous particle size distribution, was carefully separated by sieving method into three fractions which were a small size (ca. $110{\mu}m$) fraction, a medium size (ca. $220{\mu}m$) fraction and a large size (ca. $400{\mu}m$) fraction. Microscopic observations confirmed the effective separation of dry water's particle size. In extinguishing tests of wood cribs fire, the medium size dry water showed most excellent fire extinguishing performance, as compared to other dry waters having small (ca. $110{\mu}m$) and large (ca. $400{\mu}m$) particle size. The good performance of the medium size (ca. $220{\mu}m$) dry water may be attributed to the balance between cooling effect of the water core and smothering effect of the silica particles. It is also revealed that small size dry water has poor flowability than large size dry water.

• 분석과학
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• 제11권3호
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• pp.206-212
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• 1998

수확후 Alternaria, Penicillium 및 Fusarium에 이병된 고추, 양파, 마늘을 HPLC로 주요독소들을 검정한 결과 고추에서 Alternaria 독소의 AOH(alternariol)는 소량~$400{\mu}g/g$, ALT(alternuene)는 소량~$103{\mu}g/g$, TeA(tenuagonic acid)는 $249{\sim}342{\mu}g/g$ 및 AME(alternariol monomethyl ether)는 $206{\sim}294{\mu}g/g$이 검출되었고 양파, 마늘에서 Penicillium 독소의 citrinin이 $2.8{\sim}18.4{\mu}g/g$, penicillin-G는 $0{\sim}439.0{\mu}g/g$, penicillic acid는 $0{\sim}10.2{\mu}g/g$ 및 patulin은 $0{\sim}7.0{\mu}g/g$ 검출되었다. 그리고 양파, 마늘에서 Fusarium 독소로는 fusaric acid가 $0{\sim}553.6{\mu}g/g$ 검출되었을 뿐 deoxynivalenol과 nivalenol은 검출되지 않았다.