• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.9
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• pp.2463-2476
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• 1994

Local mean fluctuating velocity components were measured in the separating and reattaching axisymmetrc region of turbulent boundary layer over the wall of convex cylinders placed in a water tunnel by using 2-color 4-beam fiber optics laser Doppler velocimetry. Measurements were made with three different diameters of cylinders with four different diameters of cylinders with four different diameter of the obstructions. The range of Reynolds number based on step height was between 5,000 to 25,200. The study demonstrates that the reattachment length decreases with decreasing cylinder radius and is always shorter than that for the two-dimensional backward-facing step flow at the condition of the same step height. It was also observed that the turbulent kinetic energy in the recirculating region increases with an increases in the radius of convex curvature. The measured velocity field suggests that the transverse curvature can effect definitely the formation of corner eddy.

• Archives of Plastic Surgery
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• v.41 no.1
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• pp.81-84
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• 2014

In this article, we present two cases of femoral pseudoaneurysm (PA) at the femoral arterial puncture site followed by necrotizing fasciitis, which is rare but can be fatal when not managed appropriately. PA was revealed by lower-extremity angiography and color-flow Doppler ultrasonography. Hematoma removal, thrombolysis, and bleeder ligation with Gelfoam were repeatedly performed by a vascular surgeon. When necrotizing fasciitis developed, aggressive surgical drainage and creation of a viable wound bed for reconstruction were mandatory. We adopted a vacuum-assisted closure device (Kinetics Concepts International) as the standard treatment for complicated, serious, infected PA of the puncture site. Excellent clinical outcomes were obtained.

• Journal of Chest Surgery
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• v.51 no.3
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• pp.213-215
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• 2018

Aneurysm and pseudoaneurysm of the dorsalis pedis artery (DPA) are rare vascular entities. Pseudoaneurysms of the DPA are commonly due to blunt trauma, sharp penetrating injury, fracture, or iatrogenic injury. Herein, we report the case of a patient with a rare iatrogenic pseudoaneurysm that occurred after blood sampling. The diagnosis was suspected based on palpitation of a pulsatile mass on the dorsal foot and confirmed by color Doppler ultrasound and computed tomography angiography. Surgical treatment was successfully performed by reconstruction with an autologous venous graft. The patient recovered well, with no ischemic complications.

• Korean Journal of Veterinary Research
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• v.37 no.3
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• pp.687-692
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• 1997

개의 전립선에서 경직장 초음파상에 나타나는 미만성 저에코영역의 성상과 경직장 초음파 검사법의 유용성을 알아보기 위해 히스토그람 분석방법과 color doppler 초음파를 이용하여 전립선 맛사지에 따른 전립선 실질의 에코변화를 비교하였다. 전립선 맛사지 후 히스토그람상의 휘도치는 전립선 요도부 기준 상부측 실질내에서 유의성(p<0.01) 있게 고에코로 변화되어 나타났으며, 전립선내에 분포하는 혈관은 저에코영역에서 보다 고에코영역에서 발견되었다. 이상의 결과로 보아 경직장 초음파 검사법은 전립선의 미세한 변화에 대해 보다 상세한 실질내의 정보를 제공할 수 있는 효과적인 검사 방법이며, 맛사지에 따른 휘도치의 변화는 전립선의 물리적 자극에 대한 전립선액의 분비에 따른 결과로 사료되고, 저에코영역은 혈관보다는 전립선액이 점유하고 있는 것으로 생각된다.

• Journal of the Korean Society of Safety
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• v.19 no.3 s.67
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• pp.20-25
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• 2004

In order to obtain the flame Propagation speed in freely falling droplet suspension Produced by an ultrasonic atomizer, a light collecting probe named Multi-color Integrated Cassegrain Receiving Optics (MICRO) is applied to spark-ignited spherical spray flames. Two MICRO probes are used to monitor time-series signals of OH chemilumine-scence from two different locations in the flame. The flame propagation speed is calculated by detecting the arrival time difference of the propagating flame front. In addition, time-series images of OH chemiluminescence are simultaneously obtained by a high-speed digital CCD camera to ensure the validity of the MICRO system. Furthermore, relationship between the spray properties measured by phase Doppler anemometer (PDA) and the flame propagation speed are discussed with k different experimental conditions by changing the fuel injection rate. It was confirmed that the MICRO probe system was very useful and convenient to obtain the flame propagation speed and that the flame propagation speed was different depending on the spray properties.

• Journal of Veterinary Clinics
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• v.33 no.5
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• pp.304-306
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• 2016

A 12-month-old, 3.0-kg, male, Scottish fold cat was referred to Irion animal hospital with dyspnea and cardiac murmur. In radiograph, right-sided cardiomegaly and pleural effusion were identified. In echocardiographic examination, abnormal stenotic region was identified in right ventricle and dilation of right atrium and concentric hypertrophy of interventricular septum and the free wall of right ventricle were also identified. In the stenotic region, abnormal muscular band was identified. The turbulent flow was identified in infundibular region of right ventricular outflow tract with color-Doppler examination and high velocity flow (4.0 m/s) was also identified in stenotic region. With these results, double-chambered right ventricle (DCRV) was diagnosed.

• Journal of Veterinary Clinics
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• v.36 no.6
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• pp.336-339
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• 2019

A castrated, 6-year-old, male Turkish Angora cat with a history of respiratory distress was referred to the hospital. Physical examination revealed a cardiac murmur, and thoracic radiographic findings revealed pleural effusion and cardiomegaly. Echocardiography showed abnormality of the tricuspid and mitral valve, and color-flow Doppler imaging revealed regurgitation between both atrium and ventricle. Based on the echocardiographic examination, tricuspid valve dysplasia concurrent with mitral valve dysplasia was diagnosed. However, the patient died a week after treatment. In necropsy, bilateral atrioventricular valve dysplasia and left ventricular hypertrophy were confirmed. This is the first report to describe a middle age Turkish angora cat having bilateral atrioventricular valve dysplasia which has high mortality and only been reported rarely in cats. This case report also describes its clinical signs, diagnostic imaging findings, treatment and discussions how the patient could live long.

• Journal of Veterinary Clinics
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• v.32 no.1
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• pp.101-104
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• 2015

A 4-years-old, intact male Golden retriever dog was presented with abdominal distension and dyspnea. Physical examination revealed arrhythmia and cardiac murmur. Generalized cardiomegaly, pleural effusion and ascites were shown on thoracic and abdominal radiographs. Two-dimensional echocardiography revealed abnormal mitral and tricuspid valve motion, mitral and tricuspid regurgitation, left ventricular eccentric hypertrophy and left atrial dilation. Color-flow Doppler imaging revealed turbulent flow extending into the left ventricle during diastole from the mitral valve orifice, and into the left atrium during systole. Spectral Doppler recordings revealed highly increased early diastolic mitral valve inflow and prolonged pressure half-time of mitral inflow. Based on the echocardiographic examination, the diagnosis was made as the mitral valve dysplasia concurrent with mitral valve stenosis and tricuspid valve dysplasia.

• International Journal of Automotive Technology
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• v.6 no.5
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• pp.437-444
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• 2005

Unburned hydrocarbon (UBHC) emissions from gasoline engines remain a primary engineering research and development concern due to stricter emission regulations. Gasoline engines produce more UBHC emissions during cold start and warm-up than during any other stage of operation, because of insufficient fuel-air mixing, particularly in view of the additional fuel enrichment used for early starting. Impingement of fuel droplets on the cylinder wall is a major source of UBHC and a concern for oil dilution. This paper describes an experimental study that was carried out to investigate the distribution and 'footprint' of fuel droplets impinging on the cylinder wall during the intake stroke under engine starting conditions. Injectors having different targeting and atomization characteristics were used in a 4-Valve engine with optical access to the intake port and combustion chamber. The spray and targeting performance were characterized using high-speed visualization and Phase Doppler Interferometry techniques. The fuel droplets impinging on the port, cylinder wall and piston top were characterized using a color imaging technique during simulated engine start-up from room temperature. Highly absorbent filter paper was placed around the circumference of the cylinder liner and on the piston top to collect fuel droplets during the intake strokes. A small amount of colored dye, which dissolves completely in gasoline, was used as the tracer. Color density on the paper, which is correlated with the amount of fuel deposited and its distribution on the cylinder wall, was measured using image analysis. The results show that by comparing the locations of the wetted footprints and their color intensities, the influence of fuel injection and engine conditions can be qualitatively and quantitatively examined. Fast FID measurements of UBHC were also performed on the engine for correlation to the mixture formation results.

• Clinical and Experimental Pediatrics
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• v.45 no.4
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• pp.489-497
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• 2002

Purpose : The objectives of this study were to investigate the causes of chronic cough and to establish the appropriate diagnostic approach to chronic cough in children. Methods : One hundred and thirty two cases of chronic cough were prospectively evaluated. They visitors to pediatric chronic cough clinics at Kang-nam saint Mary's Hospital of Catholic University from August 2000 to July 2001 for 12 months. Careful history taking by questionnaire, physical examination, radiologic studies of chest and sinus, hematologic and immunologic studies, allergic skin tests, and methacholine challenge tests were performed. Color doppler(CD) ultrasonography were performed and compared with simultaneous 24 Hr. esophageal pH monitoring to diagnose gastroesophageal reflux disease(GERD). Results : Age distributions were demonstrated that nine in infants, 82 in early childhood, 38 in late childhood, and three in adolescence. Common causes of chronic cough were bronchial asthma in 40 cases, chronic sinusitis in 22 cases, GERD in seven cases, bronchial asthma combined with sinusitis in 28 cases, bronchial asthma combined with GERD in 14 cases, psychogenic cough in two. cases, foreign body in one case, chronic bronchitis in one case, and bronchiolitis in one case. Comparing with 24 Hr. pH monitoring, sensitivity, specificity, positive predictive value and negative predictive values of CD ultrasonography were 88%, 69%, 85 %, and 73% respectively. Conclusion : The most common causes of chronic cough in children were bronchial asthma, sinusitis and GERD in order. We suggest that CD ultrasonography can be used as a good, convenient screening method for patients with suspected GERD in outpatient settings.