• Title/Summary/Keyword: Wall following

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An Experimental Study of a Heat pipe with Binary Mixture Working Fluid for Solar Collector (2 성분 혼합물을 작동유체로 사용하는 태양열 집열기용 히트파이프의 실험적 연구)

  • Jung, Eui-Guk;Boo, Joon-Hong;Chung, Won-Bok
    • Proceedings of the KSME Conference
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    • 2003.11a
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    • pp.13-18
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    • 2003
  • Heat pipes with binary mixture fabricated and tested for applications where condenser temperature is in a range of $10^{\circ}C$ to $130^{\circ}C$. The pipe materials 8.0 mm O.D. cupper tube and the working fluids are ethanol-water mixtures. The total length of test of the heat pipe was 1710mm in which evaporator section was 1570mm, adiabatic section was 50mm and condenser section was 90mm. Mixing ratios of ethanol and water could be variable in mole fraction. Temperature of condenser section was $10^{\circ}C$, $80^{\circ}C$ and $130^{\circ}C$. Heat pipe performance experimental study was accomplished with change of mixing ratio in these temperatures. The fill charge ratio was 20% of the heat pipe volume. Wick structure was woven-wire and method of experimental work was that thermal load was increased 20W step until the heat pipe wall temperature reached at $150^{\circ}C$. Results were following: At coolant $10^{\circ}C$ and $130^{\circ}C$, mixing ratio that have beat thermal performance was 0.8M+ and at coolant $80^{\circ}C$, was 0.3 ${\sim}$ 0.5 M+.

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SCANNING ELECTRON MICROSCOPIC STUDY OF LINK PLUS PIN IN DENTIN (상아질에 장착된 Link plus pin의 주사전자현미경적 연구)

  • Um, Chung-Moon
    • Restorative Dentistry and Endodontics
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    • v.14 no.1
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    • pp.205-210
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    • 1989
  • The purpose of this study was to observe the minim pins of Link plus (which has buttress thread and shoulder stop design) inserted into dentin and the dentin surrounding pin. The gingival walls of class II cavity were prepared with high speed handpiece in molar teeth not elapsed time after teeth were extracted, and pinhole of 2mm in depth was positioned about 1 mm to the dentinoenamel junction and minim pin was inserted with wrench. After initial examination of the specimens, the specimens were sectioned longitudinally and horizontally to the pins with carborundum disc and low speed diamond saw (Isomet Buehler Ltd) All specimens were coated Au of 250-300${\AA}$ in thickness with Ion Sputter JFC 100 and observed under Scanning Electron Microscope (JSM-35) The following results were obtained. 1. The shoulder stop was seated on the enterance of pinhole in gingival wall, and there were the irregular space between the pin and dentin at the enterance to the pin hole and flakes of dentin lifting from the dentin floor. 2. In case of section to pin horizontally or longitudinally, the dentin debris were observed in gap between pin and dentin, and small cracks were often seen in the dentin surrounding minim pins.

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A STUDY OF THE APICAL LEAKAGE OF VARIOUS RETROGRADE TECHNIQUES (치근단 폐쇄방법에 따른 변연누출에 관한 실험적 연구)

  • Park, Sang-Ho;Lee, Chan-Young;Lee, Seung-Jong;Lee, Chung-Suck
    • Restorative Dentistry and Endodontics
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    • v.11 no.1
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    • pp.53-61
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    • 1985
  • This study was conducted to evaluate and compare the apical leakage in the following retrograde techniques; apicoectomys, retrograde filling with zinc oxide eugenol cement, non-zinc and zinc amalgam, and cold-burnished gutta-percha method. One hundred twenty five upper anterior and lower premolar teeth were divided into five above mentioned groups and each tooth was individually prepared for its particular group. The specimens were incubated at $37^{\circ}C$ for 14 days and then were infiltrated by 2% methylene blue for 24 hours. The apical leakage was evaluated by measuring the degree of dye penetration between the filling material and the canal wall. The results were as follows: 1. The cold-burnished gutta-percha group showed the least amount of apical leakage and the apicoectomy group showed the greastest amount of apical leakage. 2. Statistics showed that there were significant differences among the groups (P<0.05), however there was no difference between the zinc oxide eugenol cement retrograde filling group and the non-zinc amalgam retrograde filling group (P>0.05).

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Four Flaps Technique for Neoumbilicoplasty

  • Lee, Young Taek;Kwon, Chan;Rhee, Seung Chul;Cho, Sang Hun;Eo, Su Rak
    • Archives of Plastic Surgery
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    • v.42 no.3
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    • pp.351-355
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    • 2015
  • The absence or disfigurement of the umbilicus is both cosmetically and psychologically distressing to patients. The goal of aesthetically pleasing umbilical reconstruction is to create a neoumbilicus with sufficient depth and good morphology, with natural-looking superior hooding and minimal scarring. Although many reports have presented techniques for creating new and attractive umbilici, we developed a technique that we term the "four flaps technique" for creating a neoumbilicus in circumstances such as the congenital absence of the umbilicus or the lack of remaining umbilical tissue following the excision of a hypertrophic or scarred umbilicus. This method uses the neighboring tissue by simply elevating four flaps and can yield sufficient depth and an aesthetically pleasing shape with appropriate superior hooding.

Accidental case of large colon impaction in a horse

  • Berzina Dace;Zeeshan Muhamad;Chekarova Irina;Park Hee-Jin;Yoon Hyun-Sang;Lee Seung-Yeon;Oh Myong-Ho;Kim Bum-Seok;Lim Chae-Woong
    • Korean Journal of Veterinary Service
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    • v.29 no.1
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    • pp.79-82
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    • 2006
  • A 5 years old gelding (Thoroughbred, Equus caballus) had shown severe abdominal pain, colic, after overeating of hay in the feed storage. following through treatment, it subsequently died. Grossly, the large colon was impacted with firm mass of food and congestion of blood vessel in the intestinal wall. There were mild peritonitis and pleuropneumonia. This case demonstrates typical large colon impaction with hard consistence ingesta due to improper management of horse.

Dynamic response of heat and mass transfer in blood flow through stenosed bifurcated arteries

  • Charkravarty S.;Sen S.
    • Korea-Australia Rheology Journal
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    • v.17 no.2
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    • pp.47-62
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    • 2005
  • The present study deals with a mathematical model describing the dynamic response of heat and mass transfer in blood flow through bifurcated arteries under stenotic condition. The geometry of the bifurcated arterial segment possessing constrictions in both the parent and the daughter arterial lumen frequently appearing in the diseased arteries causing malfunction of the cardiovascular system, is formulated mathematically with the introduction of the suitable curvatures at the lateral junction and the flow divider. The blood flowing through the artery is treated to be Newtonian. The nonlinear unsteady flow phenomena is governed by the Navier-Stokes equations while those of heat and mass transfer are controlled by the heat conduction and the convection-diffusion equations respectively. All these equations together with the appropriate boundary conditions describing the present biomechanical problem following the radial coordinate transformation are solved numerically by adopting finite difference technique. The respective profiles of the flow field, the temperature and the concentration and their distributions as well are obtained. The influences of the stenosis, the arterial wall motion and the unsteady behaviour of the system in terms of the heat and mass transfer on the blood stream in the entire arterial segment are high­lighted through several plots presented at the end of the paper in order to illustrate the applicability of the present model under study.

Non-occlusive Mesenteric Ischemia (NOMI) Secondary to Traumatic Hemorrhagic Shock: Case Report (외상성 출혈성 쇼크 환자에서 발생한 비 폐쇄성 장간막 허혈)

  • Lim, Kyoung Hoon;Jung, Hee Kyung;Cho, Jayun;Lee, Sang Cjeol;Park, Jinyoung
    • Journal of Trauma and Injury
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    • v.27 no.4
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    • pp.204-207
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    • 2014
  • Non-occlusive mesenteric ischemia (NOMI) encompasses all forms of mesenteric ischemia with patent mesenteric arteries. NOMI is commonly caused by decreased cardiac output resulting in hypoperfusion of peripheral mesenteric arteries. We report a case of NOMI secondary to hemorrhagic shock and rhabdomyolysis due to trauma. A 42-year-old man presented to our trauma center following a pedestrian trauma. On arrival, he was drowsy and in a state of hemorrhagic shock. He was found to have multiple fractures, both lung contusion and urethral rupture. An initial physical examination and abdominal computed tomography (CT) scan revealed no evidence of intra-abdominal injury. High doses of catecholamine were administered for initial 3 days due to unstable vital sign. On day 25 of hospitalization, follow-up abdominal CT scan demonstrated that short segment of small bowel loop was dilated and bowel wall was not enhanced. During exploratory laparotomy, necrosis of the terminal ileum with intact mesentery was detected and ileocecectomy was performed. His postoperative course was uneventful and is under rehabilitation.

Penetrating Injury to the Left Ventricle from a Fractured Rib Following Blunt Chest Trauma (흉부 둔상으로 골절된 늑골로 인해 발생한 좌심실 천공)

  • Oh, Tak-Hyuk;Lee, Sang Cjeol;Lee, Deok Heon;Cho, Joon Yong
    • Journal of Trauma and Injury
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    • v.27 no.4
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    • pp.192-195
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    • 2014
  • The perforation of a cardiac chamber by a fractured rib after blunt trauma is a rare event. Here, we report the case of patient who was referred for multiple rib fractures after a fall from a height. The patient was found to have a penetrating cardiac injury which was detected on a computed tomography chest scan. Computed tomography is a useful screening tool for victims of blunt chest trauma. Once cardiac perforation has been confirmed or is highly suspected, it is important to preserve the patient's vital signs until reaching the operating room by minimally manuplating the chest wall and permitting hypotension, which also prevents exsanguinating hemorrhage. For the same reasons, early cardiac tamponade may also improve the patient's survival.

Spontaneous pyometra induced by Staphylococcus aureus in a Maltese (황색포도상구균 감염에 의한 어린 말티스의 자궁축농증 증례)

  • Hong, Sun-Hwa;Chung, Yung-Ho;Han, Sang-Jun;Kim, Ok-Jin
    • Korean Journal of Veterinary Service
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    • v.35 no.1
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    • pp.63-67
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    • 2012
  • An 8-months-old young Maltese bitch was presented for investigation of anorexia and occasional vomiting. The body weight was 2 kg. Abdominal sonography demonstrated abnormal enlargement of uterus. The dog had been clinically and pathologically examined. Also, ovariohystectomy was performed. Staphylococcus aureus was identified in the pus-like materials of the uterine lumen. This case was confirmed as pyometra induced by Staphylococcus aureus. Gross examination of the dissected uterus revealed enlarged uterine horn, which had yellowish or brownish pus-like materials in the lumen. Also, there was several segments formation between the enlarged areas of left and right uterine horns. Histopathologically, endometritis and necrosis were present in uterine wall. The bitch made a complete recovery following an ovariohystectomy. This case was spontaneous pyometra induced by Staphylococcus species. On our knowledge, this is a very rare report of pyometra occurrence in young dog and Staphylococcus species-induced pyometra. This study may provide a valuable data on the study of canine pyometra.

Warm Sensation of Left lower Extremity as a Complication of Left Stellate Ganglion Block (좌측성상교감신경절차단후(左側星狀交感神經節遮斷後)에 합병증(合倂症)으로 온 좌측하지온감(左側下肢溫感))

  • Oh, Hung-Kun
    • The Korean Journal of Pain
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    • v.1 no.1
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    • pp.125-128
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    • 1988
  • A case of the left stellate ganglion block (SGB) with a warm serration of the left lower extremity in a 25-year-old male soldier is presented. During the Korean War, this patient received a penetrating gun shot wound from the right knee through the left abdominal wall, left upper arm and left thumb. He was evacuated to the a marine corps surgical hospital where amputation of the left thumb and an end-to-end anatomosis of the left brachial artery were performed. After surgery, left ulnar and median nerve paralysis and causalgia developed and about 9 months later an upper thoracic ganglionectomy was proposed at the Chin-Hae Navel Hospital. Before the ganglionectomy a stellate ganglion block for diagnostic and prognostic purposes was requested by the surgeon. This block was performed by the supraclavicular anterior approach using 10 ml of 2% procaine. The effect of the block including Horner's syndrome was confirmed 5 minute later in this patient. This patient returned to the ward by walking unassisted 10 minutes after the block, and complained of a warm sensation in the left lower extremity 20 minutes later as well as the left upper arm. This warm sensation in the lower extremity following ipsilateral stellate ganglion block indicates that the local anesthetics solution injected tinto the neck spread down to lumbar sympathetic ganalgion along the fascial membrane of the sympathetic chain as a consequence of the 10 minutes walk.

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