• Journal of Yeungnam Medical Science
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• 제14권1호
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• pp.77-84
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• 1997

55명의 미숙아를 대상으로 이중 도플러 초음파 검사를 실시하여 대천문을 통한 전 뇌동맥의 혈류속도 및 혈류형태를 조사하였다. 미숙아에서 뇌 혈류속도 및 pulsatility index는 재태기간, 출생 체중, 및 미숙아의 나이 등의 증가에 따라 비례하여 증가하였으나 resistive index는 감소하였다. 뇌실 출혈이 있는 환아 군에서는 특징적인 resistive index의 증가가 보였지만 혈류속도 및 plusatility index는 불규칙하였다. 정상 미숙아의 뇌혈류 관찰 및 환아 군에서의 뇌혈류 검사에서 이중 도플러 초음파 검사는 비침습적이고 재현성도 뛰어나 선별검사로 유용한 방법이라고 생각한다.

• 한국임상수의학회지
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• 제23권4권
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• pp.427-431
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• 2006

Pulse Doppler ultrasonographic evaluation was performed to investigate the resistive index (RI) of the Interlobar renal artery in 17 dogs (32 kidneys) which were diagnosed with an acute renal failure caused by ochratoxin-A and citrinin contaminated commercial diet. RI was investigated in 7 normal beagle dogs and recovered patients. The mean of RI was resulted as $0.69{\pm}0.04$ in normal dog, however, significantly (p<0.001) increased as $0.76{\pm}0.05$ in renal failure dog. But RI had no relationship with the results of blood chemistry, urine analysis, and excretory urographic image quality. From these results, even though the results of the renal function test were within a normal reference range, it was considered that RI index is more reliable to represent a damaged renal parenchyma, and may have the potential to be a useful clinical tool in monitoring of the renal function.

• 대한물리의학회지
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• 제5권2호
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• pp.255-264
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• 2010

Purpose : The purpose of this study is to analysis effects of resistive exercise on cardiopulmonary fitness and cerebral artery blood flow velocity. Methods : Ten healthy university students had done resistive exercise without aerobic exercise over one year participated resistive exercise group and ten general university students, then were calculated oxygen consumption ($VO_2$) and respiratory exchange rate($VO_2/VCO_2$). After a week, they were measured Transcranial Doppler Ultrasonography(TCD) at moderate exercise(HRmax 50%), maximal exercise (HRmax 100%) for taking cerebral blood flow velocity. Results : In the comparison between groups, resistive exercise group showed significant higher oxygen consumption and lower respiratory exchange than controls(p<0.05). In resistive exercise group, oxygen consumption was significant negative correlation with cerebral artery pulsatory index(p<0.05). but, oxygen consumption was significant positive correlation with systolic blood flow velocity in controls(p<0.05). Conclusions : After considering all the factors, important value in resistive exercise is regular participation and help us increasing contingency response ability.

• 대한수의학회지
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• 제45권3호
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• pp.423-427
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• 2005

Color Doppler imaging (CDI) was carried out to evaluate the anesthetics effect on ophthalmic circulation using CDI-derived resistive index (RI) values. CDI was preformed on 24 dogs, and RI values were calculated for the medial long posterior ciliary artery (mLPCA) and ophthalmic artery (OA) before and after administration of anesthetics. After administration of benoxinate or acepromazine, a significant change of the mLPCA RI was not found. But, a significant decrease of the RI following ketamine (p < 0.001) or xylazine (p < 0.01) administration could be observed as compared with the self-control. Mean RI value of OA also showed this same trend. Intraocular pressure was significantly decrease following benoxinate (p < 0.01), acepromazine (p < 0.01), and xylazine (p < 0.001) administration within normal range. The results suggest that some anesthetics influence on ophthalmic vascular resistance. Therefore, chemical restraint was carefully used in clinical application of CDI-derived RI measurement. Particularly, benoxinate and acepromazine is useful chemical restraint without a change of the ophthalmic vascular resistance.

• 한국임상수의학회지
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• 제20권3호
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• pp.274-277
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• 2003

임상적으로 건강한 비글견 17두와 췌장염으로 진단된 5두(요크셔테리어 3두, 토이푸들 2두)의 견에서, 화학보정 없이 전방 십이지장동맥(cranial pancreaticodudenal artery: cPDA) 혈관저항지수(resitive index: RI)를 측정하고 이를 비교 평가하였다. RI 측정을 위해 이중 펄스 색도플러 초음파와 11-MHz 선형 위상차 배열 탐촉자를 이용하였다. 췌장염견(0.75$\pm$0.04)견의 평균 RI는 정상견(0.63$\pm$0.04)과 비교하여 유의성(t = 5.79, p = 0.001)있게 증가된 소견을 보였다. 췌장염에 이환 또는 의증 환축에서는 cPDA의 RI 평가 또한 보조적 진단 가치가 있음을 확인하였다.

• 대한전자공학회논문지
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• 제9권5호
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• pp.34-42
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• 1972

전류잡음은 탄소피막고정저항기의 품질을 나타내는 중요한 척도이다. 저항체피막상의 결함은 전류밀도의 불균형을 초래하고 결과적으로 전류잡음의 기대를 유발한다. 전류잡음의 크기는 저항재의 고유한 성질과 저항체의 처리, 조립 및 외장 등에 의한 여러 요인에 의존하고 있으나 각종 수명시험결과 저항기의 전기적특성과 전류잡음문에는 명백한 관계가 성립하고 있다. 대표군의 저항기에 대한 전류잡음지수의 정규분포를 표시하는 parameter를 해석하면 제품의 품질관리와 생산의 균일성을 판단하는 지표로서 매우 유용한 수단이다.

• 한국임상수의학회지
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• 제20권2호
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• pp.145-149
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• 2003

개의 정상안혈관저항지수와 그 재현성을 측정하고자 컬러도플러 초음파를 이용하여 본 실험을 수행하였다. 내측 긴 후모양체 동맥, 모양체 동맥, 안동맥의 혈관저항지수의 정상범주를 측정하기 위하여 58두의 개에서 컬러도플러 초음파를 실시하였다. 정상견에서 내측 긴 후모양체동맥, 모양체동맥, 안동맥의 저항지수(%)를 측정한 결과, 그 수치는 각각 0.67$\pm$0.07, 0.70$\pm$0.06, 그리고 0.08$\pm$0.04이었으며, 모든 혈관의 저항지수는 좌우안구간에 차이가 없었으며, 성별이나 두개골 형태가 미치는 영향도 없는 것으로 판명되었다. 안혈관 저항지수의 반복측정에 따른 오차를 평가하기 위해서 4회 반복 측정한 결과, 안동맥저항지수의 반복측정변이계수가 4.1%로 가장 낮았으며 긴 후모양체동맥과 모양체동맥의 저항지수의 반복측정변이계수는 각각 12.9%와 7.8%로 모든 동맥에서 높은 재현성을 보였다. 이상의 결과로 보아, 컬러도플러 초음파가 개의 안구 및 안와의 혈순환에 대한 객관적인 측정자료를 제시하는데 매우 유용한 지표인 것으로 판단된다.

• 대한수의학회지
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• 제39권4호
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• pp.832-837
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• 1999

lntrarenal resistive index (RI) was determined in normal, sedated and diuretic kidneys. The mean RI values of normal dogs were $0.64{\pm}0.03$ without statistically significant difference between left and right kidney. Interrenal RI difference (${\Delta}RI$) was $0.03{\pm}0.01$. No significant relationship was found between mean intrarenal RI versus body weight. The mean intrarenal RI values after administration of acepromazine, xylazine, thiopental, and ketamine were $0.66{\pm}0.03$, $0.64{\pm}0.03$, $0.56{\pm}0.05$, and $0.50{\pm}0.05$, respectively. After administration of acepromazine or xylazine, a significant change of the RI was not found. But, a significant decrease of the RI following thiopental or ketamine administration could be observed as compared with the normal RI. The mean intrarenal RI values were $0.63{\pm}0.06$ and $0.62{\pm}0.04$ at 10 minutes and 30 minutes after injection of furosemide, respectively. No significant change of intrarenal RI was found after administration of furosemide. But, mannitol significantly decreased mean intrarenal RI to $0.57{\pm}0.02$ and $0.58{\pm}0.03$ at 30 minutes and 60 minutes, respectively. Based on the obtained results, values of 0.72 and 0.05 may be proposed as the reasonable upper limits of RI and ${\Delta}RI$ of normal average. Acepromazine or xylazine are recommended as anesthetics for renal diseases because they have less effect on the RI. Further study using mannitol injection to increase ${\Delta}RI$ may be suggested in unilateral urinary tract obstruction since mannitol more effectively changed mean RI than furosemide.

• 한국전기전자재료학회논문지
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• 제29권6호
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• pp.327-331
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• 2016

Resistive random access memory (ReRAM) of metallic conduction channel mechanism is based on the electrochemical control of metal in solid electrolyte thin film. Amorphous chalcogenide materials have the solid electrolyte characteristic and optical reactivity at the same time. The optical reactivity has been used to improve the memory switching characteristics of the amorphous $As_2Se_3$-based ReRAM. This study focuses on the formation of holographic lattices patterns in the amorphous $As_2Se_3$ thin film for straight conductive channel. The optical parameters of amorphous $As_2Se_3$ thin film which is a refractive index and extinction coefficient was taken by n&k thin film analyzer. He-Cd laser (wavelength: 325 nm) was selected based on these basic optical parameters. The straighten conduction channel was formed by holographic lithography method using He-Cd laser.$ Ag^+$ ions that photo-diffused periodically by holographic lithography method will be the role of straight channel patterns. The fabricated ReRAM operated more less voltage and indicated better reliability.

• 한국전기전자재료학회논문지
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• 제22권10호
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• pp.854-859
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• 2009

The YBCO coated conductor is an important element that forms the superconducting power equipment. The first advantage of applying YBCO coated conductor to superconducting power equipment is that it can effectively addresses the normal and fault currents using less quantity of wire than when using Bi tape due to its high critical current density. Second, it can limit the fault current fast because its index value is high. so that the resistance can be produced fast when it is applied to the superconducting current limiting element. Third, the type of stabilization layer that surrounds the YBCO superconductor is selectable and the magnitude of the resistance that is produced from quenching can be adjusted. This study researched into the manufacture of current-limiting element of using YBCO coated conductor, into the characteristics of current limiter that considered by combining the manufactured element with the resistive-type superconducting fault current limiter.