• Title/Summary/Keyword: Head shape

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A New Free-living Marine Nematode Species of the Genus Dracogalerus Allen and Noffsinger (Nematoda: Draconematidae) from a Shallow Subtidal Zone of Jeju Island, Korea

  • Rho, Hyun-Soo;Kim, Won
    • Animal cells and systems
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    • v.9 no.3
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    • pp.113-122
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    • 2005
  • A new species of free-living marine draconematid nematode, Dracogalerus koreanus n. sp., is described from the shallow subtidal coarse sediments and various invertebrates of Jeju Island, Korea. This is the first record of this genus from Korea. Dracogalerus koreanus n. sp. is morphologically most similar to D. cryptocephalus (Irwin-Smith) in having similar head shape (rostrum broadly rounded anteriorly) and eight cephalic adhesion tubes, but differs by the small number of rounded protuberances on the ventral side of non-annulated tail end (5 vs 6), small number of posterior subventral adhesion tubes in male (5-6 vs 8), intermingled somatic setae (5-6 vs absent), spicules (slightly curved and relatively thick vs strongly curved and very slender), and higher 'c' value in male (8.8 vs 7.5).

Experimental Study on the Performance of a Cross-Flow Fan with Various Diameter Ratios of Impeller and Rearguider Shapes (임펠러 직경비 및 리어가이더 형상변화가 횡류홴 성능에 미치는 실험적 연구)

  • Kim, H.S.;Kim, D.W.;Yoon, T.S.;Park, S.K.;Kim, Youn-J.
    • 유체기계공업학회:학술대회논문집
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    • 2003.12a
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    • pp.391-396
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    • 2003
  • A cross-flow fan relatively produces higher dynamic pressure at low speed because a working fluid passes through an impeller blade twice and blades have a forward curved shape. The performance of a cross-flow fan is influenced 25% by the impeller, 60% by the rearguider and the stabilizer, and 15% by the heat exchanger. At the low flow rate, there exist a rapid pressure head reduction, a noise increase and an unsteady flow against a stabilizer and a rearguider. The purpose of this study is to investigate the reciprocal relation among each parameter Experiments are conducted to study the effects of a rearguider and a diameter ratio of impeller on the performance analysis of a cross-flow fan. Comparing with the rearguider of radial type, the Archimedes type shows excellent results for various diameter ratios.

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Performance Improvement of Fan and Duct System for Kimchi Refrigerator (김치 냉장고용 홴 및 덕트 시스템 성능 개선)

  • Kim, Joon-Hyung;Choi, Young-Seok;Yoon, Joon-Yong;Park, Sung-Kwan;Hyun, Seok-Ho
    • The KSFM Journal of Fluid Machinery
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    • v.14 no.4
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    • pp.45-51
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    • 2011
  • The kimchi refrigerator is the electronic home appliance which is used for the maturing and a custody of the kimchi. In this paper, performance improvement of fan and duct system for kimchi refrigerator has been studied by using a commercial CFD code. In order to achieve a improved fan performance, three-dimensional computational fluid dynamics and the Design of Experiments method have been applied. Additionally, to know the optimized duct inlet shape with the optimized fan, the overall performances were calculated with various duct inlet shapes. The final fan and duct system for kimchi refrigerator showed improved performance in efficiency and total head compared with the existing model.

Application of Three-dimensional Reconstruction in Esophageal Foreign Bodies

  • Chang, Ji-Min;Yoo, Young-Sam;Kim, Dong-Won
    • Journal of Chest Surgery
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    • v.44 no.5
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    • pp.368-372
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    • 2011
  • This study was conducted to investigate the clinical application of three-dimensional (3D) reconstructed computed tomography (CT) images in detecting and gaining information on esophageal foreign bodies (FBs). Two patients with esophageal FBs were enrolled for analysis. In both cases, 3D reconstructed images were compared with the FB that was removed according to the object shape, size, location, and orientation in the esophagus. The results indicate the usefulness of conversion of CT data to 3D images to help in diagnosis and treatment. Use of 3D images prior to treatment allows for rapid prototyping and surgery simulation.

Thyroplasty Type I using Gore-Tex (고어텍스를 이용한 제1형 갑상연골성형술)

  • Yoo, Young-Sam
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.18 no.1
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    • pp.16-21
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    • 2007
  • Many kinds of materials have been used up to now for vocal fold paralysis. Although silastic block has been the most popular material, some difficulties in carving, positioning, and placing have been the causes to find more easily applicable materials. Hy-droxylapatite, gelfoam, hyaluronic acid and fat have been suggested and used for this purposes with some limitations. During last decade, Gore-Tex was introduced and replacing old materials and showed good surgical results with less difficulties. This material is biocompatible and familiar to surgeons because it had been invented in 1960's. In addition it is easy to shape and place Gore-Tex into the window with many clinical experiences. In some problem cases, it is easy to remove from the body with less damage to surrounding tissue. The basic surgical techniques are as follows. 1) Creating window. 2) Positioning and placing the material. 3) Immobilizing the material and closing the window. The modified methods ae introduced in details with figures.

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Reliability Evaluations for Shear Strength of Resistance Welded Ball Stud according to Different Cooling Methods

  • Park, In-Duck;Nam, Ki-Woo
    • Journal of Power System Engineering
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    • v.22 no.6
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    • pp.44-50
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    • 2018
  • As a type of bolt with a spherical head, the ball stud is widely used as a part of a ball joint in steering or suspension systems in automobiles. Balls and studs are subjected to heat treatment suitable for each material; in particular, the shear strength of the ball stud must meet the specifications of the production company. This study evaluated the shear strength of joints according to the cooling method of ball studs subject to resistance welding. The shear stress of water cooling was higher than that of air cooling (as-received material). Note, however, th at oil cooling showed lower stress than that of as-received. When judged by standard deviation, mean, and coefficient of variation according to the arithmetic statistics and shape parameter as well as scale parameter, oil cooling is suitable.

Effect of Radiative Mean Temperature on Thermal Comfort of Underfloor Air Distribution System (바닥공조시스템에서 복사온도가 열적쾌적성에 미치는 영향)

  • Chung, Jae-Dong;Hong, Hi-Ki;Yoo, Ho-Seon
    • Proceedings of the SAREK Conference
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    • 2006.06a
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    • pp.15-20
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    • 2006
  • Despite the fact that UFAD (Under Floor Air Distribution) systems have many benefits and are being applied in the field in increasing numbers, there is a strong need for an improved fundamental understanding of several key performance features of these systems. This study numerically investigates the effect of design parameters on the performance of UFAD, especially focused on thermal comfort. The design parameters considered in this study include supplied air temperature, supplied flow rate, diffuser shape, swirl, diffuser location, and floor-to-floor height. Also this study has compared UFAD with over head system, on the point of thermal comfort by evaluating PMV using radiative mean temperature, which shows how inadequate the evaluation of thermal comfort can be when radiation is neglected. Until now, the radiative temperature has been the missing link between CFD and thermal comfort, but the present study paves the way for overcoming this weakness.

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DYNAMIC CHARACTERISTICS OF A PARTIALLY FLUIDFILLED CYLINDRICAL SHELL

  • Jhung, Myung-Jo;Yu, Seon-Oh;Lim, Yeong-Taek
    • Nuclear Engineering and Technology
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    • v.43 no.2
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    • pp.167-174
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    • 2011
  • A pressurizer in a small integral type pressurized water reactor is located inside the upper region of the reactor vessel, and uses a space between the upper head of the reactor vessel and the upper region of the upper guide structure which is partially filled with fluid depending on the operating power. This new design requires a comprehensive investigation of vibration characteristics. This study investigates the modal characteristics of a pressurizer which uses a simplified cylindrical shell model, focusing on how having fluid in the shell affects vibration and response characteristics. In addition, an analysis of sloshing is performed and the response characteristics are addressed.

Vehicle Detection for Adaptive Head-Lamp Control of Night Vision System (적응형 헤드 램프 컨트롤을 위한 야간 차량 인식)

  • Kim, Hyun-Koo;Jung, Ho-Youl;Park, Ju H.
    • IEMEK Journal of Embedded Systems and Applications
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    • v.6 no.1
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    • pp.8-15
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    • 2011
  • This paper presents an effective method for detecting vehicles in front of the camera-assisted car during nighttime driving. The proposed method detects vehicles based on detecting vehicle headlights and taillights using techniques of image segmentation and clustering. First, in order to effectively extract spotlight of interest, a pre-signal-processing process based on camera lens filter and labeling method is applied on road-scene images. Second, to spatial clustering vehicle of detecting lamps, a grouping process use light tracking method and locating vehicle lighting patterns. For simulation, we are implemented through Da-vinci 7437 DSP board with visible light mono-camera and tested it in urban and rural roads. Through the test, classification performances are above 89% of precision rate and 94% of recall rate evaluated on real-time environment.

Giant basal cell carcinoma of the left lateral neck

  • Baik, Bongsoo;Park, Sulki;Ji, Soyoung;Kim, Sunyoung
    • Archives of Craniofacial Surgery
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    • v.22 no.3
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    • pp.173-176
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    • 2021
  • Basal cell carcinoma is a malignant epithelial neoplasm of the skin and the most common human skin cancer. It is generally associated with a good prognosis. In this case report, a giant basal cell carcinoma of the nodulo-ulcerative type showing wide ulceration with marginal multiple small nodules, is presented. It was trapezoidal in shape, having dimensions of 7 cm at the greatest basal width, 6 cm vertically with different anterior and posterior margin dimensions, and 5 cm horizontally at the top margin. After wide excision of the lesion including 5-10 mm safety margins, the wound was reconstructed with a local skin flap and split-thickness skin graft. The reconstructed wound healed well without recurrence for 1 year.