Laser Doppler Flowmetry를 이용한 치은혈류량에 관한 연구

김형수,이장희,송형근,김병옥,한경윤,Kim, Hyung Soo,Lee, Zang-Hee,Song, Hyung-Geun,Kim, Byung-Ock,Han, Kyung-Yoon 대한치주과학회 1998 Journal of Periodontal & Implant Science Vol.28 No.2

The periodontal health has been evaluated clinically by various epidemiological indices, and in researches by measurement of gingival crevicular fluid. Laser Doppler flowmetry is a reliable and objective method that allows immediate measurement of erythrocyte flux in approximately one cubic mm of the capillary bed without disturbing the tissues. The purpose of the present study was to determine whether human gingival blood flow was different according to measuring area, measuring time, and sex or not. Forty volunteers with good general and periodontal health, aged early twenties and unmarried, were selected. Laser Doppler flowmetry($floLAB^{(R)}$, Moor Instruments Ltd., England) was applied to measure the gingival blood flow of marginal gingiva, interdental papilla, attached gingiva and alveolar mucosa. The blood flow of interdental papilla was measured at 9-10 AM, 1-2 PM, and 5-6 PM. The difference of blood flow according to measuring area and measuring time was statistically analyzed by one way AOVA and Dunkan test, and the difference of blood flow between men and women was statistically analyzed by t-test. (1) Mean blood flow was significantly higher in alveolar mucosa than in the gingiva(p<0.05), and there was no significant difference in blood flow between marginal gingiva and interdental papilla(p>0.1). (2) Mean blood flow was significantly higher at 5-6 PM than at 9-10 AM and 1-2 PM(p<0.05). But there was no significant difference in gingival blood flow between 9-10 AM and 1-2 PM(p>0.1). (3) There was no significant difference in gingival blood flow between men and women(p>0.1). The above results suggest that the measurment of gingival blood flow using laser Doppler flowmetry may be clinically applicable to early determination of gingival inflammation and evaluation of healing status, but further studies are necessary to standardize and simplify the measuring procedure.

주철분말의 소결조직에 (燒結組織) 미치는 산화철 (酸化鐵) 첨가의 효과

김형수,김철범,나형용 ( Hyung Soo Kim,Chul Bohm Kim,Hyung Yong Ra ) 한국주조공학회 1990 한국주조공학회지 Vol.10 No.2

N/A The microstructures of sintered products of Fe₂O₃or Fe₃O₄-Oxide added cast iron powder was investigated. And the effects of particle size distribution was investigated too. As the result, the structures of sintered products did not related to the species of Fe-Oxide. Th porosity of sintered products was decreased in size and spherodized with increasing sintering temperature, decreasing Fe-Oxide quantity. Fe-Oxide itself did not hinder sintering of cast iron powder particularly, therefore sintering could be occurred without termination of reduction of it. And the sintered products of finer particle size distribution had finer and more spherodized porosity, and had minimized the deviation of size and shape of porosity.

분말사출성형 시 분말 혼합체의 유동성 시뮬레이션을 통한 투광성 알루미나 소결체의 특성 연구

김형수,변종민,김세훈,김영도,Kim, Hyung Soo,Byun, Jong Min,Kim, Se Hoon,Kim, Young Do 한국분말야금학회 2014 한국분말재료학회지 (KPMI) Vol.21 No.3

Translucent alumina is a potential candidate for high temperature application as a replacement of the glass or polymer. Recently, due to the increasing demand of high power light emitting diode (LED), there is a growing interest in the translucent alumina. Since the translucent property is very sensitive to the internal defect, such as voids inside or abnormal grain growth of sintered alumina, it is important to fabricate the defect-free product through the fabrication process. Powder injection molding (PIM) has been commonly applied for the fabrication of complex shaped products. Among the many parameters of PIM, the flowability of powder/binder mixture becomes more significant especially for the shape of the cavity with thin thickness. Two different positions of the gate were applied during PIM using the disc type of die. The binder was removed by solvent extraction method and the brown compact was sintered at $1750^{\circ}C$ for 3 hours in a vacuum. The flowability was also simulated using moldflow (MPI 6.0) with two different types of gate. The effect of the flowability of powder/binder mixture on the microstructure of the sintered specimen was studied with the analysis of the simulation result.

주철분말의 소결성에 (燒結性) 미치는 산화철 (酸化鐵) 첨가의 효과

김형수,김철범,나형용 ( Hyung Soo Kim,Chul Bohm Kim,Hyung Young Ra ) 한국주조공학회 1990 한국주조공학회지 Vol.10 No.1

N/A In order to lower the cabon content of sintered products below the solubility of austenite, Fe-oxide was added to cast iron powder of which matrix was pearlite. And the effects of it on some sintering properties and mechanical properties were investigated. Roughly speaking, the linear shrinkage, density, and tensile strendth of sintered properties increased as the sintering temperature became higher, the size distribution of powder became finer, and the amount of Fe-oxide added became less. The maximum tensile strength of sintered products was 78㎏f/㎟ more or less, of which carbon content was 1.4% and sintering temperature was 1180℃.

교통량 측정 시스템에서의 프레임간 차영상을 이용한 차량 검출 및 추적

김형수,황기현,Kim, Hyung-Soo,Hwang, Gi-Hyeon 한국융합신호처리학회 2016 융합신호처리학회 논문지 (JISPS) Vol.17 No.1

지능형 교통 시스템(Intelligent Transportation System, ITS)은 첨단기술을 사용하여 도로의 상황을 판단하고 적절한 처리를 수행하므로 이상적인 차량의 흐름을 유도하는 시스템이다. 교통상황에 대한 정보는 다양한 지점에서 측정되고 관리되어야 하므로 주로 컴퓨터를 이용한 영상이 사용된다. 컴퓨터를 이용한 영상처리는 실시간으로 다양한 교통 파라미터를 수집하기 용이한 방법이고, 기술들도 점점 발전하고 있다. 지능형 교통 시스템의 교통 파라미터 중 차량 검출은 기본적으로 매우 중요한 기술이다. 이를 위해 영상의 배경 차를 이용한 검출방법, 에지를 이용한 윤곽선 추출 방법 등의 기술들이 사용되고 있으나 검출률의 정확도에 문제점이 제기되고 있다. 본 논문에서는 레이블링에 의한 차량검출과 감지선을 이용한 영상처리 방법으로 차량을 검출하였다. 제안된 방법의 정확도를 확인하기 위해 국도와 고속도로 등 두 곳의 장소에서 20개의 수직, 수평 방향 영상을 수집하여 차량 계수를 측정하였다. 그 결과 수직 방향 92%, 수평 방향 91.3%의 검출률을 얻었다. Intelligent Transport Systems (Intelligent Transportation System: ITS) is a system for inducing a flow of ideal car for using the most advanced technology, it is determined the status of the road, and take appropriate action. In order to be measured at various time points, and is managed, the information about the traffic situation is used image using a computer mainly. The image processing using a computer, it is an easy way to collect parameters of the various traffic in real time, technology has developed more and more. Vehicle detection of transport parameters of intelligent transportation system is a very important technology basically. Therefore, technology detection method using car background images and the contour line extraction method using an edge is used, however, problems have been raised on the accuracy of the detection rate.

소뇌 혈관아세포종 전적출 후 천막상에 발생한 혈관아세포종 - 증 례 보 고 -

김형수,박세혁,조병문,김덕환,오세문,Kim, Hyung Soo,Park, Se-Hyuck,Cho, Byung Moon,Kim, Duck-Hwan,Oh, Sae-Moon 대한신경외과학회 2001 Journal of Korean neurosurgical society Vol.30 No.2

Hemangioblastoma is a benign tumor of vascular origin that develops usually in the posterior cranial fossa. We report a case of supratentorial leptomeningeal hemangioblastoma occurring in a 45-year-old man who received total removal of recurrent cerebellar hemangioblastoma four years ago. He was admitted for the evaluation of severe headache and magnetic resonance image showed a well-enhanced, extra-axial mass in the right parietal region. A presumptive diagnosis was meningioma. It was completely removed with the attached dura. Histological examination including immunohistochemical study showed typical findings of hemangioblastoma. It is emphasized that close observation may be necessary for hemangioblastoma, even after total removal.

KT의 그린ICT 전략 "Green KT, Green Korea"

김형수,Kim, Hyung-Soo 한국정보통신학회 2009 한국정보통신학회지 Vol.10 No.1

선천성 거대결장증 수술 후 문합부에 발생한 점액성 대장선암: 증례 보고

김형수,윤권하,Kim, Hyung-Soo,Yoon, Kwon-Ha 대한영상의학회 2004 대한영상의학회지 Vol.50 No.1

선천성 거대결장증으로 수술한 후의 장기 추적에서 문합부에 악성종양이 생긴 경우는 보고된 바가 없다. 저자들은 선천성 거대결장증으로 26년전에 Soave 수술을 받은 환자의 문합부에생긴 점액성 대장선암를 경험하였기에 이를 보고하는 바이다. To our knowledge, rectal cancer arising at the anastomotic site after surgery for Hirschsprung's disease has not been reported. We report a case of mucinous adenocarcinoma arising at the anastomotic site after Soave operation 26 years ago.

2차유동이 평판후류의 난류구조에 미치는 영향

김형수,이준식,강신형,Kim, Hyeong Soo,Lee, Joon Sik,Kang, Shin Hyung 대한기계학회 1999 大韓機械學會論文集B Vol.23 No.9

The effects of secondary flow on the structure of a turbulent wake generated by a flat plate was investigated experimentally. The secondary flow was induced In a $90^{\circ}$ curved duct in which the flat plate wake generator was installed. The wake generator was installed in such a way that the wake velocity gradient exists in the span wise direction of the curved duct. Measurements were made in the plane containing the mean radius of curvature where pressure gradient and curvature effects were small compared with the secondary flow effect. All six components of the Reynolds stresses were measured in the curved duct. Turbulence intensities in the curved wake are higher than those in the straight wake due to an increase of the turbulent kinetic energy production by the secondary flow. In the inner wake region, shear stress and strain in the plane containing the velocity gradient of the wake show opposite signs with respect to each other, so that eddy viscosity Is negative in this region. This indicates that gradient-diffusion type turbulence models are not appropriate to simulate this type of flow.

PET상 이상소견을 보인 Marchiafava-Bignami병: 증례 보고

김형수,Kim, Hyung-Soo 대한영상의학회 2004 대한영상의학회지 Vol.50 No.1

We report the FDG PET findings in a patient with Marchiafava-Bignami disease (MBD) in whom there was diffusely reduced metabolism in the whole brain cortex and strongly decreased metabolism in the thalami. The use of FDG PET helps provide an understanding of the neurologic manifestations and prognosis of MBD. Marchiafava-Bignami 병은 알코올 중독과 관련된 드믄 질환으로 주로 뇌량의 탈수초화가 일어나며,MRI 등 영상소견으로 진단할 수 있다.저자들은 FDG PET상 대뇌 피질의 전반적인대사 감소와 시상의 심한 대사 감소 소견이 보인 1예를 경험하여 보고한다. FDG PET는 MBD의 신경학적 증상이해와 예후 예측에 도움이 될 것으로 생각한다.