• Title/Summary/Keyword: Doppler Effects

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Doppler Velocity-based Dynamic Object Tracking and Rejection for Increasing Reliability of Radar Ego-Motion Estimation (레이더 에고 모션 추정 신뢰성 향상을 위한 도플러 속도 기반 동적 물체 추적 및 제거)

  • Park, Yeong Sang;Min, Kyoung-Wook;Choi, Jeong Dan
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.21 no.5
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    • pp.218-232
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    • 2022
  • Researches are underway to use a radar sensor, a sensor used for object recognition in vehicles, for position estimation. In particular, a method of classifying dynamic and static objects using the Doppler velocity, the output from the radar sensor, and calculating ego-motion using only static objects has been researched recently. Also, for the existing dynamic object classification, several methods using RANSAC or robust filtering has been proposed. Still, a classification method with higher performance is needed due to the nature of the position estimation, in which even a single failure causes large effects. Hence, in this paper, we propose a method to improve the classification performance compared to existing methods through tracking and filtering of dynamic objects. Additionally, the method used a GMPHD filter to maximize tracking performance. In effect, the method showed higher performance in terms of classification accuracy compared to existing methods, and especially shows that the failure of the RANSAC could be prevented.

Can Daily-use Lipstick Make Lips More Fresh and Healthy\ulcorner - A New Lipstick Containing $\alpha$-Glucosyl-hesperidin Can Remove the Dull-color from Lips

  • Iwai, I.;Yamashita, T.;Ochiai, N.;Masuda, Y.;Hosokawa, K.;Kohno, Y.
    • Proceedings of the SCSK Conference
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    • 2003.09a
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    • pp.162-177
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    • 2003
  • It has been known that the color of skin reflects the blood flow within. In lips, the capillaries close to the skin surface are numerous; hence lips are redder than the rest of face. However, dermatological research on lips is not as advanced as research on facial or body skin, and little was known about the relationship between relatively dull-colored lips and skin blood flow. The physiological differences between colorful and dull-colored lips were studied by a two-dimensional laser Doppler blood flow analyzer, a spectrometer for the measurement of the degree of oxygen saturation, and a confocal microscope for observing inside lips non-invasively. Dull-colored lips and the corner of lips (dull-colored compared to the center) showed relatively poor blood flow and lower oxygenated hemoglobin. It was found that colorful lips (generally the young) had a blood flow that tended to run straight in parallel with the skin surface. This unique blood-capillary structure can express clear red blood. Those with dull-colored lips had lost this unique structure. Their blood ran perpendicularly from the deep of the skin and down back again into the deep part as like the blood circulation patterns of facial skin. Therefore, the lips of the latter group had fewer blood capillaries near skin surface in the lips than that of the colorful-lips group. A lipstick containing a-glucosyl-hesperidin, which is derived from certain citrus fruits and can enhance blood circulation, was applied for evaluating its effects. Blood flow was increased 30 min after the application. After two weeks of daily application, the lips' condition became noticeably less dull. These findings suggest that the decrease of blood flow in dull-colored lips is caused by the loss of the unique capillary structure and the use of the lipstick to increase blood flow can give a vivid color to lips.

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Enhancement of in vivo Radiosensitization by Combination with Pentoxifylline and Nicotinamide (Pentoxifylline과 Nicotinamide의 병용에 의한 생체내 방사선 감수성 증강 효과)

  • Lee Intae;Cho Moon-June
    • Radiation Oncology Journal
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    • v.9 no.1
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    • pp.7-15
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    • 1991
  • Pentoxifylline (PENTO) has been known to improve RBC fluidity, and thus improve the flux of RBC through narrow capillaries. Additionally, PENTO also decreases the $O_2$ affinity of hemoglobin by increasing 2,3-DPG levels, thereby increasing the $O_2$ release from RBC. Nicotinamide (NA) has been reported to decrease the number of acutely hypoxic cells in tumors by temporarily increasing tumor blood flow. Therefore, the purpose of this study was to examine whether the combination of PENTO and NA (PENTO+NA) would reduce the radioresistance of the Fsall murine fibrosarcoma by oxygenating the hypoxic cells. We obsewed a significantly enhanced radiation-induced growth delay of the FSaII tumors by PENTO+NA. Thus the enhancement ratio was between 2.5 and 2.8 in growth delay assay. The $TCD_{50}$ of control tumors was about 57 Gy, but that of PENTO+NA treated tumors was about 32Gy. Thus $TCD_{50}$ was modified by a factor of 1.8. We also observed that PENTO+NA exerted no effect on the radiation-induced skin damage after the legs without bearing tumors were exposed to X-irradiation. In order to clarify radiosensitizing effects of PENTO+ NA, changes in tumor blood flow and intratumor pOf were measured using laser Doppler flowmetry and $O_2$ microelectrode methods. The tumor blood flow significantly increased at 10 min. after injection of PENTO+ NA. Furthermore, we also found that PENTO+ NA significantly increased intratumor $pO_2$ from 8 to 19 mmHg. We concluded that PENTO+MA was far more effective than NA alone or PENTO alone. The increase in the response of tumors in vivo to X-irradiation appeared to be due mainly to an increase in the tumor oxygenation. Further studies using various concentrations of PENTO alone and in combination with NA to obtain better sequencing and maximal radiosensitization are warranted.

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A New Shock Index for Predicting Survival of Rats with Hemorrhagic Shock Using Perfusion and Lactate Concentration Ratio (흰쥐의 출혈성 쇼크에서 관류와 젖산 농도 비를 이용한 새로운 생존 예측 지표 개발)

  • Choi, Jae-Lim;Nam, Ki-Chang;Kwon, Min-Kyung;Jang, Kyung-Hwan;Kim, Deok-Won
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.48 no.4
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    • pp.1-9
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    • 2011
  • Hemorrhagic shock is a clinically widespread syndrome characterized by inadequate oxygenation and supply. It is important to diagnose hemorrhagic shock in its early stage for improving treatment effects and survival rate. However, an accurate diagnosis and treatment could be delayed in the early stage of hemorrhagic shock by evaluating only vital signs such as heart rate and blood pressure. There have been many studies for the early diagnosis of hemorrhagic shock, reporting that lactate concentration and perfusion were useful variables for tissue hypoxia and metabolic acidosis. In this study, we measured both perfusion using a laser Doppler flowmeter and lactate concentration from the volume controlled hemorrhagic shock using rats. We also proposed a new shock index which was calculated by dividing lactate concentration by perfusion for early diagnosis. As a result of the survival prediction by the proposed index with the receiver operating characteristic curve method, the sensitivity, specificity, and accuracy of survival were 90.0, 96.7 and 94.0%, respectively. The proposed index showed the fastest significant difference among the other parameters such as blood pressure and heart rate. It could offer early diagnosis and effective treatment for human hemorrhagic shock if it is applicable to humans.

Evaluation of short-term cardiac function by tissue Doppler imaging in pre and postoperative period of congenital heart disease (조직 도플러 영상을 이용한 선천성 심장병 수술 전후의 단기 심기능 평가)

  • Lee, Jun-Hwa;Kim, Yeo-Hyang;Hyun, Myung-Chul;Lee, Sang-Bum
    • Clinical and Experimental Pediatrics
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    • v.50 no.5
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    • pp.476-483
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    • 2007
  • Purpose : The objective of this study was to assess ventricular function by tissue Doppler imaging (TDI) in children with congenital heart disease (CHD) who have been undergoing open heart surgery (OHS) using cardiopulmonary bypass. We tried to compare the parameters of tissue Doppler imaging before and after OHS in patients with congenital heart disease. Methods : This study was conducted on 32 patients with CHD after OHS from January 2005 to December 2005 at Kyungpook National University hospital. Patients who underwent 2-D echocardiography before and after their OHS. All patients were divided into three groups, left ventricular volume overloading group (group 1), and right ventricular volume overloading group (group 2), and right ventricular pressure overloading group (group 3). The TDIs were examined before and 1 to 3 months after OHS. Peak early diastolic (E), and peak late diastolic (A) velocity of transmitral flow were measured by pulsed wave Doppler examination. Peak systolic (Sm), peak early diastolic (Em), and peak late diastolic (Am) velocity in apical 4-chamber and 2-chamber views were measured by TDI. The author calculated E/Em ratio. Results : The patients were 14 boys and 18 girls and the average age of patients was 2 years and 3 months. The congenital heart diseases which have to get OHS were ventricular septal defect (13 cases), atrial septal defect (7), atrioventricular septal defect (3), isolated pulmonary stenosis (2) and tetralogy of Fallot (7). There were significant decrease of Sm, Em, Am measured on tricuspid annulus and E/Em measured on mitral annulus in apical 4 chamber view (P<0.05). Conclusion : This study showed significant decrease of Sm, Em, Am measured on tricuspid annulus and E/Em measured on mitral annulus in apical 4 chamber view after OHS. These changes might be due to the effects of cardiopulmonary bypass in OHS and/or hemodynamic changes after correction of congenital heart disease. To clarify these changes, further study on more patients is needed.

The Effects of Moxibustion at CV12 on Cerebral Blood Flow and Peripheral Blood Flow (중완(中脘)에 신기구 뜸시술이 뇌혈류 및 말초혈류 변화에 미치는 영향)

  • Kim, Do-Hyung;Park, Seung-Chan;Cho, Min-Kyoung;Kwon, Jung-Nam;Hong, Jin-Woo;Lee, In
    • The Journal of Internal Korean Medicine
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    • v.35 no.1
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    • pp.24-36
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    • 2014
  • Objectives : This study was performed to evaluate the effects of moxibustion on cerebral blood flow, peripheral blood flow and blood pressure. Methods : We designed a randomized, cross-over study that included 20 healthy, male volunteers who were randomly assigned to one of two groups (the moxibustion group or the control group). The initial trial was followed by a washout period of one week before the groups were switched and the trial repeated. The cerebral blood flow and peripheral blood flow of the volunteers in both groups were measured by mean velocity (Vm), peak systolic velocity (Vs), pulsatility index (PI), perfusion units (PU) and mean blood pressure (BP) before the intervention (baseline), 30 minutes after the intervention, and again 60 minutes after the intervention. Results : 1. The Vm increased significantly in the moxibustion group. The Vs also constantly increased in moxibustion group, but there was no significant difference. 2. The PI decreased significantly in the control group at 0-30 minutes and in the moxibustion group at 30-60 minutes. 3. The PU constantly decreased in moxibustion group. In control group, the PU decreased at 30 minutes and increased slightly at 60 minutes. 4. The mean blood pressure did not show any significant difference between the two groups. Conclusions : This study shows that moxibustion at CV12 increased the cerebral blood flow. Based on this result, we can suggest that moxibustion at CV12 might be helpful in improving the functional recovery of stroke patients. However, further research needs to be conducted on a larger numbers of subjects in order to confirm these effects.

Effect of Soumin Seonghyangjeongkisan Extract on Blood Pressure and Regional Cerebral Blood Flow in Rats (소음인(少陰人) 성향정기산(星香正氣散)이 백서(白鼠)의 혈압(血壓) 및 국소뇌혈류량(局所腦血流量)에 미치는 영향(影響))

  • Lee, Ki-ju;Kim, Kyung-yo
    • Journal of Sasang Constitutional Medicine
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    • v.12 no.1
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    • pp.228-239
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    • 2000
  • 1. Purpose : For many years, Soumin Seonghyangjeongkisan(少陰人 星香正氣散, SJ) has been used in Sasang(四象) constitutional medicine as a therapeutic agent for cerebral disease. The effects of SJ on the vascular system is not well-know. The purpose of this study is to make it clear the effects of SJ and composing drugs on blood pressure(BP) and regional cerebral blood flow(rCBF). 2. Method : We measured BP with Pressure Transducer, rCBF with Laser-Doppler flowmeter. Propranolo and methylene blue were used to determine the mechanisms of SJ effects. 3. Results and Conclusion : BP was not affected by SJ in rats, and rCBF was significantly increased by SJ in rats. rCBF was increased by Folium Perillae(蘇葉), Rhizoma Atractylodis(蒼朮), Pericarpium Arecae(大腹皮) and Rhizoma Arisaematic(南星), but decreased by Radix Saussurea(木香) in rats. The increase of rCBF is mediated by adrenergic ${\beta}-receptor$ and guanylyl cyclase which is enzyme producing cyclic GMP.

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Effect of Taeumin Chungsimyoinjatang Extract on Blood Pressure and Regional Cerebral Blood Flow in Rats (태음인(太陰人) 청심연자탕(淸心連子湯)이 백서(白鼠)의 혈압(血壓) 및 국소뇌혈류량(局所腦血流量)에 미치는 영향(影響))

  • Park, Jae-hyung;Kim, Kyung-yo
    • Journal of Sasang Constitutional Medicine
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    • v.12 no.1
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    • pp.216-227
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    • 2000
  • 1. Purpose For many years, Taeumin Chungsimyoinjatang(太陰人 淸心蓮子湯, CS) has been used in Sasang(四象) constitutional medicine as a therapeutic agent for cerebral disease. The effects of CS on the vascular system is not well-known. The purpose of this study is to make it clear the effects of SJ and composing drugs on blood pressure(BP) and regional cerebral blood flow(rCBF). 2. Method We measured BP with Pressure Transducer, rCBF with Laser-Doppler flowmeter. Propranolol and methylene blue were used to determine the mechanisms of CS effects. 3. Results and Conclusion BP was not affected by CS in rats, and rCBF was significantly increased by CS in rats. rCBF was increased by Nelumbinis Semen(蓮于肉), Ophiopogonis Radix(麥門冬), Asparagi Radix(天門冬), Polygalae Radix(遠志), Zizyphi Spinosae Semen(酸棗仁), Longnae Arillus(龍眼肉), Raphani Semen, Chrysanthemi Flos(甘菊) in rats. The increase of rCBF is mediated by adrenergic ${\beta}$- receptor and guanylyl cyclase which is enzyme producing cyclic GMP.

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Effects of Sahyangsohap-won on Cerebral Hemodynamics in Healthy Subjects (사향소합원(麝香蘇合元)이 정상인의 뇌혈류역학에 미치는 영향)

  • Koo, Bon-Soo;Kim, Sung-Hwan;Moon, Sang-Kwan;Cho, Ki-Ho;Kim, Young-Suk;Bae, Hyung-Sup;Lee, Kyung-Sup;Ryu, Soon-Hyun
    • The Journal of Internal Korean Medicine
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    • v.22 no.2
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    • pp.199-205
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    • 2001
  • Background and Purpose : Transcranial doppler ultrasonography(TCD) is a noninvasive and nonradioactive technique for evaluation of the hemodynamics in large cerebral vessels. Sahyangsohap-won(SS) has been considered to be effective for the treatment of various disease, especially cerebrovascular, cardiovascular, and psychosomatoform disorders. But, there is no study about the effect of SS on the cerebral hemodynamics in humans. The aim of this study was to assess the effect of SS on the changes in cerebral hemodynamics and the dose-dependant effect by using TCD. Subjects and Methods : 30 healthy subjects were randomly divided into three group: group 1 took no drug, group 2 took SS one pill, and group 3 took SS 2 pills. Changes in the mean blood flow velocity(MBFV) and pulsatility index(PI) in the middle cerebral artery were evaluated by means of TCD. We obtained hypercapnia with breath-holding and evaluated cerebrovascular reactivity with the breath-holding index(BHI). Systolic blood pressure(SBP), diastolic blood pressure(DBP), and heart rate(HR) were measured by means of ambulatory blood pressure monitoring. In group 2 and group 3, the evaluations were performed during the baseline and were repeated at 20, 40, and 60 minutes after SS administration. In group 1, the evaluation was performed at corresponding time intervals. Results : In mean values of MSFV, PI, SSP, DBP, and HR, no stastically significant differences were found between the 3 groups. However, BHI values were significantly lower in groups 2 and 3 than in group 1 at 40 minutes after SS administration(P<0.05, group 1 vs group 2, group 1 vs group 3 by post-hoc analysis: Scheffe's test) but in dose-dependant effect, there was no difference between group 2 and group 3. Conclusion : These results suggest that SS can decrease vascular resistance in cerebral small arteries or arterioles and enhance their distensibility. Further studies on larger numbers of subjects are needed to confirm these effects and the dose-dependant effects.

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Effects of Convective Flow Fields on the Physical Vapor Transport Processes of $Hg_2Cl_2$ Crystals (염화제일수은 승화법 단결정 성장 공정에서의 대류 현상 연구)

  • Park, Jang-Woo;Kim, Geug-Tae;M.E. Glicksman
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1997.10a
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    • pp.39-43
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    • 1997
  • Mercurous chloride (Hg$_2$Cl$_2$) has many advantages in its applications to acousto-optic, and opto-electronic devices because it has the unique properties of a broad transmisson range, well into the far infra-red, a low acoustic velocity, a large birefringence, and a high acousto-optic figure of merit[1]. Hg$_2$Cl$_2$ has a high vapor pressure, hence single crystals are usually grown by physical vapor transport(PVT) method in closed silica glass ampoules. We discuss the application of the laser Doppler velocimetry to measure the flow field inside a closed ampoule. The experimental results, are discussed its relationship to computational model and compared to their expectations.

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