• Title/Summary/Keyword: Small Vessels

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A Study on the Flow Analysis according to the change of Surface Roughness Gap in the Leisure Ship (레저선박의 표면조도 간격변화에 따른 유동해석에 관한 연구)

  • Oh, Woo-Jun;Cho, Dea-Hwan;Lee, Dong-Sub;Shon, Chang-Bae;Lee, Gyoung-Woo
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2009.10a
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    • pp.243-244
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    • 2009
  • From large to small vessels of the surface is not smooth. and The surface ship has a surface roughness. Because surface roughness increases the surface resistance and heat transfer, be considered when designing a ship that is an important design factor. Due to surface roughness study on flow around and due to changes in flow and turbulence intensity for the ongoing research is conducted. Roughness of the surface ships from the ship by air as well as machines can be widely applied. In this study, the surface roughness of the leisure marine interval, any change will affect the surface flow, area due to surface roughness for boundary-experimental study was performed.

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A Study on the Constraints for the Redevelopment of Conventional Pire in Busan Port (부산항 북항 재개발 관련 선결과제 고찰)

  • Jang Woo-Joon;Kang Dal-Won;Jeon Chan-Tong;Nam Ki-Chan
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2006.06b
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    • pp.147-152
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    • 2006
  • Nowadays, the redevelopment of the conventional pier in Busan port has been one of top issues on Busan port. Busan Port Authority has already launched a research project on that and the Master Plan undergoing. However, the conventional pier is still booming one for small vessels providing feeder service to and from Busan port and both Japanese ports and Chinese ones. Accordingly, there are several terminal operation companies(TOC) and union workers which make might be a major obstacle for the redevelopment. Furthermore, it has been said that alternative pier is necessary before starting redevelopment. Under such circumstance this paper tries to review the major limitations and provide some thought for the solution.

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A Case of $Henoch-Sch{\"{o}}nlein$ Purpura with Hemorrhagic Bullae in a Child (소아에서 출혈성 수포를 동반한 $Henoch-Sch{\"{o}}nlein$ 자반병 1례)

  • Oh Yeon-Mi;Jung Mi-Rim;Choi Hye-Jeong;Cha Hee-Jeong;Jeong Jin-Young
    • Childhood Kidney Diseases
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    • v.10 no.1
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    • pp.40-44
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    • 2006
  • [ $Henoch-Sch{\"{o}}nlein$ ] purpura(HSP) is a systemic small vessel vasculitis characterized by cutaneous purpura, arthritis, abdominal pain and nephritis. The characteristic rash of HSP consists of palpable purpura on the buttocks and lower extremities. Bullous lesions often appear in adults with HSP, whereas they are very rare in children with HSP. In this case report, the patient presented with arthralgia and abdominal pain and had hemorrhagic bullae as a prominent manifestation of the disease. The skin biopsy of the patient revealed typical leukocytoclastic vasculitis of dermal vessels and prominent IgA and fibrinogen deposits on capillary walls by direct immunofluorescence. We confirmed the diagnosis of HSP and observed improvement of clinical symptoms and signs within a few days after corticosteroid treatment. We therefore report a case with a review of the literature.

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Morphological Study on Differentiation of Hepatocytic Stem Cell by Intrasplenic Transplantation after Partial Hepatectomy (간부분 절제술 후 비장내 이식한 간세포화 줄기세포의 분화에 관한 형태학적 연구)

  • 양영철;박재홍;박중규;배기원
    • Journal of Life Science
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    • v.12 no.3
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    • pp.294-305
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    • 2002
  • This study was performed to evaluate regenerative effects of intrasplenic stem cell transplantation after partial hepatectomy. To evaluate the regenerative effects, Sprague Dawley rats were used. In vivo the embryonic stem cells of blastocysts were collected from superovulated rats on day 3.5 after the vaginal plug checked. The embryonic stem cells were cocultured with hepatocytes for 8 days, they were transplanted into the spleen. After the intrasplenic transplantation of cultured stem cells, they were initially distributed near the periarterial lymphatic sheath after transplantation in the hematoxylin-eosin staining. Their number were formely increased and their size enlarged at forming small lobules. The embryonic stem cells in the culture proliferated and initially proliferated around the periarterial lymphatic sheath and later they around the trabecula with blood vessels. After the transplantation of stem cells, their cell organelles were well developed rough endoplasmic reticulum at the 20th with prominent epidermal growth factor reaction, developed smooth endoplasmic reticulum at the 30th day, well differentiated bile canaliculi with increased transforming growth factor-$\beta$ and apoptosis reactions.

Dual Electrospinning to Manufacture Hybrid Nanofibrous Scaffold using Polyurethane and Poly(Ethylene Oxide) (Polyurethane과 Poly(Ethylene Oxide)를 이용한 hybrid 나노섬유 지지체의 제작)

  • Shin, Ji-Won;Shin, Ho-Jun;Heo, Su-Jin;Kim, Ji-Hee;Hwang, Young-Mi;Kim, Dong-Hwa;Shin, Jung-Woog
    • Journal of Biomedical Engineering Research
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    • v.27 no.5
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    • pp.224-228
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    • 2006
  • The object of this study is to investigate the potential of dual-electrospun polymer based structure for vascular tissue engineering, especially for the medium or small sue blood vessels. Polyurethane(PU), which is known to be biocompatible in this area, was electrospun with poly(ethylene oxide) (PEO). Concentration of PU was fixed at 20wt%, while that of PEO was set from 15 to 35wt%. Morphological features were observed by SEM image and measurement of porosity and cellular responses were tested before and after extracting PEO from the hybrid scaffolds by immersing the scaffolds into distilled water. The diameter of PEO fibers were ranged from 200nm to 500nm. The lower concentration of PEO tended to show beads. The porosity of the scaffolds after extracting PEO was highly increased with higher concentration of PEO as expected. Also, higher proliferation rate of smooth muscle cells was observed at higher concentration of PEO than at the lower concentration and without PEO. As conclusions, this dual electrospinning technique combined with PU and PEO is expected to overcome the current barrier of cell penetration by providing more space for cells to proliferation.

Pulp vitality and coronal discoloration following traumatic injuries (치아외상 후 치아 변색과 치수 생활력의 변화)

  • Yoon, Tae-Sun;Kong, Hyung-Gyu;Kim, Eui-Seong
    • Restorative Dentistry and Endodontics
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    • v.35 no.6
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    • pp.492-496
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    • 2010
  • Coronal discoloration is a common sequela to traumatic injuries. In subluxation cases, although the injury is not strong enough to rupture the apical vessels, discoloration may appear by tearing thin walls or occluding small capillaries. In absence of infection pulpal regeneration can occur, and as a result discoloration may completely or partially subside. But judging pulpal status by coronal discoloration can be dangerous and it may lead to unnecessary treatment. This case presents coronal discoloration and recovery following traumatic injury of maxillary anterior teeth. In diagnosing traumatized teeth routine cold tests or electric pulp tests are known to be unreliable, but with the aid of ultrasound doppler imaging, assessing pulp vitality of traumatized teeth can be more accurate.

Value of Indocyanine Green Videoangiography in Deciding the Completeness of Cerebrovascular Surgery

  • Moon, Hyung-Sik;Joo, Sung-Pil;Seo, Bo-Ra;Jang, Jae-Won;Kim, Jae-Hyoo;Kim, Tae-Sun
    • Journal of Korean Neurosurgical Society
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    • v.53 no.6
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    • pp.349-355
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    • 2013
  • Objective : Recently, microscope-integrated near infrared indocyanine green videoangiography (ICG-VA) has been widely used in cerebrovascular surgery because it provides real-time high resolution images. In our study, we evaluate the efficacy of intraoperative ICG-VA during cerebrovascular surgery. Methods : Between August 2011 and April 2012, 188 patients with cerebrovascular disease were surgically treated in our institution. We used ICG-VA in that operations with half of recommended dose (0.2 to 0.3 mg/kg). Postoperative digital subtraction angiography and computed tomography angiography was used to confirm anatomical results. Results : Intraoperative ICG-VA demonstrated fully occluded aneurysm sack, no neck remnant, and without vessel compromise in 119 cases (93.7%) of 127 aneurysms. Eight clipping (6.3%) of 127 operations were identified as an incomplete aneurysm occlusion or compromising vessel after ICG-VA. In 41 (97.6%) of 42 patients after carotid endarterectomy, the results were the same as that of postoperative angiography with good patency. One case (5.9%) of 17 bypass surgeries was identified as a nonfunctioning anastomosis after ICG-VA, which could be revised successfully. In the two patients of arteriovenous malformation, ICG-VA was useful for find the superficial nature of the feeding arteries and draining veins. Conclusion : ICG-VA is simple and provides real-time information of the patency of vessels including very small perforators within the field of the microscope and has a lower rate of adverse reactions. However, ICG-VA is not a perfect method, and so a combination of monitoring tools assures the quality of cerebrovascular surgery.

Development of an Engine Simulator for Optimal Control System Implementation of a Gas Turbine Engine (가스터빈엔진 최적 제어시스템 구현을 위한 엔진 시뮬레이터 개발)

  • Cha, Young-Bum;Koo, Bon-Min;Song, Do-Ho;Choi, Jung-Keyng
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.1
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    • pp.75-82
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    • 2007
  • In advanced countries, a gas turbine engine is developed to use in aircraft, vessels, and target weapons. Our nation also passed the level of producing engine components and now, we are developing small-sized gas turbine engine. The most important point of the gas turbine engine, the engine control technique, is evaded by the advanced nations. This document contains the research about the development of the gas turbine engine simulator. The simulator presented in this document has a mathematical engine model based on a capacity data of the gas turbine engine to advance the engine simulator. Through this process, it eases the development of the gas turbine engine control algorithm and helps to check the engine controller function. In this simulator, the engine sensor signal conversion board is designed, so the engine model shows like a real sensor signal during the simulation. Also, this paper contrasts the actual engine test with the simulation results to verify the performance.

Comparison of Based on Histogram Equalization Techniques by Using Normalization in Thoracic Computed Tomography (흉부 컴퓨터 단층 촬영에서 정규화를 사용한 다양한 히스토그램 평준화 기법을 비교)

  • Lee, Young-Jun;Min, Jung-Whan
    • Journal of radiological science and technology
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    • v.44 no.5
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    • pp.473-480
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    • 2021
  • This study was purpose to method that applies for improving the image quality in CT and X-ray scan, especially in the lung region. Also, we researched the parameters of the image before and after applying for Histogram Equalization (HE) such as mean, median values in the histogram. These techniques are mainly used for all type of medical images such as for Chest X-ray, Low-Dose Computed Tomography (CT). These are also used to intensify tiny anatomies like vessels, lung nodules, airways and pulmonary fissures. The proposed techniques consist of two main steps using the MATLAB software (R2021a). First, the technique should apply for the process of normalization for improving the basic image more correctly. In the next, the technique actively rearranges the intensity of the image contrast. Second, the Contrast Limited Adaptive Histogram Equalization (CLAHE) method was used for enhancing small details, textures and local contrast of the image. As a result, this paper shows the modern and improved techniques of HE and some advantages of the technique on the traditional HE. Therefore, this paper concludes that various techniques related to the HE can be helpful for many processes, especially image pre-processing for Machine Learning (ML), Deep Learning (DL).

Multiple Microvenular Hemangioma Clinicopathologically Mimicking Early Stage Kaposi Sarcoma: A Case Report (초기 단계의 카포시육종과 임상조직학적으로 유사한 다발성미세소정맥혈관종 1예)

  • Eun, Dong Hyuk;Kim, Seok Min;Kim, Jun Young;Han, Man-Hoon;Lee, Seok-Jong
    • Korean journal of dermatology
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    • v.56 no.10
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    • pp.631-635
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    • 2018
  • Microvenular hemangioma (MVH) is a rare acquired benign vascular neoplasm, which presents commonly as a solitary purple-to-red nodule or plaque measuring approximately 10 mm in diameter. MVH occurs primarily on the extremities or the trunk. Most lesions are solitary, and multiple lesions are rare. Histopathological features of MVH include numerous, scattered, thin and irregularly branching small vessels in the dermis and endothelial cells without atypia. Owing to similarities in clinical morphology and histopathological features, MVH may often be indistinguishable from the early patch stage of Kaposi sarcoma. Immunohistochemical (IHC) analysis helps differentiate between the 2 diseases. The results of IHC tests in patients with MVH show positive staining for CD31 and smooth muscle actin and typically, negative staining for the human herpes virus 8 antigen. We report a rare case of multiple MVH clinically mimicking the early patch stage of Kaposi sarcoma in a 63-year-old woman who presented with a 3-year history of slowly growing, compressible, soft, bluish-purple macules and plaques on the trunk and right arm.