• Journal of Advanced Marine Engineering and Technology
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• 제32권2호
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• pp.268-275
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• 2008

The shape and array of ice capsules are very important factors in ice thermal storage system because the heat transfer rate of the system strongly depends upon them. In this paper, a new type of ice capsule composed of bar and ring module is proposed to increase the efficiency of the ice thermal storage system. To investigate the heat transfer rate of the proposed ice capsule, numerical analysis of the incompressible Navier-Stokes equations is performed to compare the proposed bar and ring system with the conventional ice capsules. It is shown that the ice capsule composed of bar and ring has a higher heat transfer rate and a low outlet temperature than the conventional ice capsules for various packing ratios and entrance velocities. Furthermore, it is found that the optimal entrance velocity exists between 0.005 m/s and 0.007 m/s from the present numerical analysis.

• Advances in aircraft and spacecraft science
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• 제4권4호
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• pp.487-501
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• 2017

The main purpose of the paper is to analyze effect of geometrical parameters of the reentry capsules such as radius of the spherical cap, shoulder radius, back shell inclination angle and overall length on the flow field characteristics. The numerical simulation with viscous flow past ARD (Atmospheric Reentry Demonstrator), Soyuz (Russian) and OREX (Orbital Reentry EXperimental) reentry capsules for freestream Mach numbers range of 2.0-5.0 is carried out by solving time-dependent, axisymmetric, compressible laminar Navier-Stokes equations. These reentry capsules appear as bell, head light and saucer in shape. The flow field features around the reentry capsules such as bow shock wave, sonic line, expansion fan and recirculating flow region are well captured by the present numerical simulations. A low pressure is observed immediately downstream of the base region of the capsule which can be attributed to fill-up in the growing space between the shock wave and the reentry module. The back shell angle and the radius of the shoulder over the capsule are having a significant effect on the wall pressure distribution. The effects of geometrical parameters of the reentry capsules will useful input for the calculation of ballistic coefficient of the reentry module.

• 대한기계학회논문집A
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• 제27권11호
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• pp.1849-1855
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• 2003

Newly commercialized wireless capsule endoscope has many advantages compared to conventional push-type endoscopes. However, it is moved by the peristaltic waves. Therefore, it can not diagnose desired zones actively. In this paper, a locomotive mechanism for wireless capsule endoscope is proposed to increase the efficiency of endoscopy. We designed and fabricated a prototype using SMA springs and bio-mimetic clamping device. The hollow space in the prototype is allocated for further system integration of a camera module, a RF module and a battery. And the sequential control scheme is employed to improve the efficiency of its locomotion. To validate the performance of the locomotive mechanism, experiments on a silicone rubber pad and in vitro tests are carried out. The results of the experiments indicate that proposed mechanism is effective in harsh environments such as digestive organs of a human.

• 한국어류학회지
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• 제21권4호
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• pp.283-286
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• 2009

고려홍어의 모식산지인 한반도 남서해안에서 포획한 암컷개체의 자궁에서 직접 적출한 난각 2개를 새롭게 기재하였다. 본종의 난각은 다른 종과 비교하여 보통 크기이고, 뿔(horn)을 포함한 전장은 124.5~133.7 mm, 뿔을 제외한 주부(main portion)의 체장은 102.8~109.4 mm, 최대폭은 41.0~42.2 mm이다. 측면에서 볼 때 배쪽으로 불룩한 비대칭이고, 표면은 비교적 부드러운 편이지만 세로로 미세한 고랑(longitudinal striations)은 뚜렷하고, 매우 발달한 섬유다발(견상사(絹狀絲) silky fibers)로 덥혀 있다. 앞뒤의 apron은 뚜렷하며, 네 뿔은 짧고 튜브모양이고 그 횡단면은 타원형이고, 앞쪽 뿔은 안쪽으로 심하게 구부러져 있으며, 호흡공(respiratory fissure)은 네 뿔의 끝부분에 위치한다. 신선한 상태에서 밝은 갈색이다.

• 대한수의학회지
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• 제37권3호
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• pp.463-469
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• 1997

This study was performed to investigate the gross anatomical features and microscopical structures of the hemal nodes and the hemolymph nodes in the water deer (Hydropotes inermis) found in Kangwon-do, Korea. The hemal nodes and hemolymph nodes were observed mainly in the periphery of the thoracic and abdominal aortae of the animals. The size of hemal nodes was generally smaller than that of the hemolymph nodes, and the shape of the both organs was spherical or ovoid. The color of the hemal nodes was red or black while that of the hemolymph nodes was gray with red bands. The hemal nodes were surrounded by a thin connective tissue capsule and there were extensive subcapsular and deep sinuses distended by a great number of erythrocytes. Although a few number of lymphatic nodules and small areas of diffuse lymphatic tissues were observed in the parenchyma, no typical cortex and medulla were defined in the hemal node. Small numbers of blood vessels were found at the connective tissue capsule but lymph vessel was not observed microscopically in this organ. The hemolymph nodes were covered by a relatively thick connective tissue capsule and there was a hilus in each node. The parenchyma was divided into cortex and medulla. The cortex was composed of a few numbers of lymphatic nodules and some diffuse lymphatic tissues. The medulla comprised medullary sinus and cords. Afferent and efferent lymph vessels were observed at the periphery of the capsule and the hilus, respectively. The subcapsular and medullary sinuses were not extensive but filled with small numbers of erythrocytes. The stroma of hemal node and hemolymph node was composed of reticular cells and fibers, and the capsule and trabecula consisted of collagenous fibers with smooth muscle fibers.

• Asian Pacific Journal of Cancer Prevention
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• 제15권2호
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• pp.855-860
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• 2014

Background: The purpose of this study was to assess the relationship between different sonographic features of papillary thyroid carcinoma (PTC) on high-frequency ultrasound and cervical lymph node metastasis (CLNM). Materials and Methods: We enrolled 548 patients who underwent initial surgery for PTC between May 2011 and December 2012 in our hospital at diagnosis. The sonographic features of 513 PTC nodules in 513 eligible patients, who had single PTC nodules in their thyroid glands, were retrospectively investigated. All patients with a suspect malignant nodule (d<0.5cm) among multiple nodules were initially diagnosed by fine-needle aspiration biopsy (FNAB) to ascertain if the suspect nodule was PTC. The final diagnosis of all the thyroid nodules and existence of CLNM were based on postoperative pathology. Patients were divided into two groups: a positive group with CLNM (224 nodules) and a negative group without CLNM (289 nodules). The following factors were investigated: gender, age, echogenicity, echotexture, size, shape, location, margin, contour, calcification morphology, distance between the nodule and pre- or post-border of the thyroid capsule, vascularity and the differences between the two groups. Results: Correlation analysis showed that shorter distances between the nodule and pre- or postborder of thyroid capsule resulted in greater risk of CLNM (Spearman correlation coefficient=-0.22, p<0.0001). The significant factors in multivariate analysis were age<45yrs, larger size (d>1cm), "wider than tall" shape, extrathyroid extension and mixed flow (internal and peripheral) (p<0.05, OR=0.406, 2.093, 0.461, 1.610, 1.322). Conclusions: Significant sonographic features of PTC nodules in preoperative high-frequency ultrasound are crucial for predicting CLNM.

• 대한기계학회논문집A
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• 제31권9호
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• pp.903-909
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• 2007

A fatigue capsule is one of the special capsules to investigate the fatigue characteristics of the nuclear materials during an irradiation test in a research reactor, HANARO. In this study, the performance test and the preliminary fatigue test results by using a cyclic load device newly developed for a fatigue capsule are described. In order to obtain the characteristics such as a realization and a controllability of the periodic wave shape and the relationship between the pressure and the load, a spring and rigid bar specimens are used. The fatigue test for the 316L stainless steel specimen with 1.8mm in diameter and 12.5mm in gage length is also performed under the same conditions as the temperature($550^{\circ}C$) of the specimen during irradiation tests. As a result of the test, the fracture of the specimen occurs at a total of 70,120 cycles(about 12 days), and the displacement in this case is 2.02 mm. It is expected that these results will be used for determining test conditions and a comparison of the in-pile fatigue test results.

• 한국작물학회지
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• 제29권4호
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• pp.376-385
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• 1984

참깨의 개화, 착삭습성을 조사하여 참깨 다수종품 종육성 및 재배법 개선을 위한 기초자료로 이용코자 8개의 초형을 공시하여 조사한 결과 다음과 같은 몇가지 결론을 얻었다. 1. NMB(단경형, 1과성2실4방)형에서는 총37화중 평균 81％의 착삭률을 나타내었으며 NMQ(단경형 1과성4실8방)형에서는 66화중 평균 70％의 착삭률을 보였다. 2. 착삭부위별 착삭률은 NMB형에서는 착화하위부 94％, 중위부 89％, 상위부 63％의 착삭률을 나타낸데 대해서 NMQ형에서는 하위부 77％, 중위부 82％, 상위부에서 불과 50％의 착삭률만을 보여 차이가 컸다. 3. NTB(단경형, 3과성 2실4방)형에서는 109화중 84화에서 삭이 형성되어 평균 77％의 착삭률을 나타냈으며 NTQ(단경형, 3과성4실8방) 형에서는 75화중 53화에서 삭이 형성되어 70％의 착삭률을 보였다. 4. 착화부위별 착삭률은 NTB형에서 착화하위부 89％, 중위부 87 ％, 상위부 44％의 착삭률의 보인데 대해서 NTQ형에서는 하위부 76％, 중위부 78％ 상위부 45％의 착삭률을 보여 단경형 4실8방에서만은 착삭률에서 중위부 ＞ 하위부 ＞ 상위부의 특별한 습성을 보였다. 5. BMB (분지형 1과성2실4방)형에서는 110화중 83％의 높은 착삭률을 나타냈으며 BMQ(분지형 1과성 4실8방)형에서는 88화중 67％의 낮은 착삭률을 보였다. 6. BMB형의 주경에서는 88％, 분지에서는 80％의 양호한 착삭률을 보였으며 BMQ형에서는 주경 81％, 분지 53％로서 분지착삭률이 낮았다. 7. BTB (분지형 3과성 2실4방)형에서는 200화중 62％의 저조한 착삿률을 보였으나 화수와 착삭수는 전공시초형 중 가장 많았으며 BTQ형에서는 113화중 62％의 낮은 착삭률을 보였다. 8. BTB형의 주경착삭률은 70％, 분지착삭률은 58％를 나타냈으며, BTQ형의 주경착삭률은 66％ 분지착삭률은 42%를 나타내어 착삭률이 모든 초형중에서 가장 낮았다. 9. 분지형에서는 주경착삭률 평균 73％ 분지착삭률 평균 61％이며 주경에서는 하위부 85％, 중위부 72％, 상위부 57％인데 대해서 분지에서는 하위부가 74％, 상위부가 48％의 착삭률을 보였다. 10. 착삭수와 착삭률등 착삭습성을 좌우하는 것은 삭실의 형태(실방수)가 가장 크게 영향을 미치는 것으로 판단되었다. 11. 참깨의 다수성 품종육종 방향은 분지성에 3과성인 2실4방형 (BTB형) 초형특성을 구비한 계통을 선발하는데 있다.

• 대한수의학회지
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• 제31권4호
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• pp.381-387
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• 1991

Deer hemal nodes were studied by gross anatomy and light microscopy. Hemal nodes were scattered in the periphery of thoracic and abdominal aortae, and spherical or avoid in shape. A hemal node consisted of a thin capsule and a hilum, and had numerous small subcapsular and deep sinuses distended by a great number of erythrocytes. Although a few lymphatic nodules and tissues were seen in the parenchyma, no typical cortex and medulla was defined. Blood vessels occurred, but lymph vessel was not observed in nodes. The parenchyma of the hemal node consisted of many erythrocytes and lymphocytes, and a few granulocytes, plasma cells megakaryocytes and macrophages. The stroma was composed of reticular cells and fibers. The capsule and trabecula was a collagenous connective tissue with smooth myofibers. The above findings suggest that the hemal nodes are involved in blood storage, blood filtration and immune reaction.

• 대한수의학회지
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• 제34권2호
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• pp.229-235
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• 1994

The hemal nodes of the Korean native cattle were studied by gross anatomy and light microscopy. Hemal nodes were spherical or ovoid in shape, and red or black in colors. A hemal node consisted of a thick capsule and a hilum, and had extensive subcapsular and deep sinuses distended by a great number of erythrocytes. Although a few lymphatic nodules and tissues were seen in the parenchyma, no typical cortex and medulla was defined. Blood vessels occurred, but lymph vessel was not observed in nodes. The stroma of the hemal node was composed of reticular cells and fibers. The parenchyma consisted of many erythrocytes and lymphocytes, and a few macrophages and megakaryocytes. The capsule and trabecula was a collagenous connective tissue with smooth muscle cells. B-lymphocytes were principally located in the lymphatic nodules of the hemal node. T-lymphocytes were scattered in the diffuse lymphatic tissues of the hemal node.