스텝 펄스파를 사용하는 캐스케이드 인버터에서 스위치의 간단한 도통각 계산법

김형창,김태진,강대욱,현동석 전력전자학회 2003 전력전자학회 논문지 Vol.8 No.6

최근에 높은 전력과 전압의 적용을 위한 방법으로써 PWM 방법보다는 스템 펼스파률 이용해 출력 전압 레벨을 조합하는 멀티레벤 인버터가 폭 넓게 사용되어지고 았다 이 땅식은 도통각을 통해 한주기에 한번만 온,오프 하기때문에 스위칭 손실 측띤얘서 유리한 특성을 갖는다i 본 논문에서는 도똥각을 얻는 간단한 방법을 제안하며 이 방법 은 출력 전압 레밸에 의해 나누어진 기준 전압 파형의 전압-시간 면적들을 통해 인버터의 출랙 스템 펄스피·흘 구성 한다 또한 제안한 방법은 근사법에 의한 연립방정식의 해를 구할 펼요가 없기 때문에 기존의 빙법과는 달리 계산량 을 줄일 수 있고 온 라인에 의해 도통각을 얻올 수 있는 장점이 있다.

마두령(馬兜鈴)이 혈관(血管) 평활근(平滑筋)에 미치는 영향(影響)

김형창,류도곤,한종현,이호섭,Kim Hyung-Chang,Ryu Do-Gon,Han Jong-Hyun,Lee Ho-Sub 경락경혈학회 2000 대한침구의학회지 Vol.17 No.1

Fructus Aristolochiae has been used in Korea for many centuries as a treatment for various disease.The purpose of the present study is to determine the effect of Fructus Aristolochiae on norepinephrine(NE) induced blood vessel contraction in rabbits. Rabbit(2 kg, male) were killed by $CO_2$ exposure and a segment (8-10mm) of each rabbit was cut into equal segments and mounted in a tissue bath. Contractile force was measured with force displacement transducers under 2-3 g loading tension. The dose of norepinephrine(NE) which evoked 50% of maximal response ($ED_{50}$) was obtained from cumulative dose response curves for NE ($10^{-6}{\sim}10^{-3}M$). Contractions evoked by NE ($ED_{50}$) were inhibited significantly by Fructus Aristolochiae in abdominal aorta and femoral artery. Fructus Aristolochiae inhibited the relaxation pretreated propranolol and L-NNA in femoral artery. But Fructus Aristolochiae did not effect the relaxation pretreated ODQ in femoral artery and abdominal aorta. These results indicate that Fructus Aristolochiae can relax NE induced contraction of rabbit blood vessel selectively, and that this relaxation relates to nitric oxide synthesis and sympathetic action.

만성 척수손상환자를 대상으로 한 척수손상 - 기능실현평가지수의 타당성 연구

김형창,이석민,송창호 대한작업치료학회 2007 대한작업치료학회지 Vol.15 No.2

목적:본 연구의 목적은 새로 개발된 척수손상-기능실현평가지수(SCI-ARMI)를 만성 척수손상환자들에게 적용하여 척수손상-기능실현평가지수 추정식을 산출하고, 추정식의 추정력에 대한 신뢰도와 타당도를 알아보는 데 있다. 연구방법:본 연구는 S병원에서 2006년 1월에서 동년 6월 사이에 입원치료를 받은 손상 후 6개월 이상 경과한 ASIA A-C인 만성 척수손상환자 66명을 선정하여 입·퇴원 시 ASIA 근력점수와 SCIMⅡ를 이용하여 신경학적 상태와 기능적 상태를 평가하여 회귀분석으로 통계 처리하였다. 결과:ASIA 근력점수가 SCIMⅡ 점수에 통계적으로 유의한 영향을 미쳤다. ASIA 근력점수로 각각의 손상레벨별 SCIMⅡ 최고 점수를 예측하는 회귀식을 이용하여 척수손상-기능실현평가지수를 쉽게 계산할 수 있는 추정식을 구하였다. 추정식에 의해 구한 기능실현평가지수 값과 기능실현평가지수 정의에 의해 구한 기능실현평가지수 값 사이에 높은 상관관계(r=.723, p<.05)를 보였다. ASIA 근력점수, 나이, 손상원인, 재활기간, 손상레벨과 기능실현 평가지수 값 사이에는 유의한 상관관계가 없었다. 결론:ASIA 척도 A-C인 경우의 만성 척수손상환자들에게서 구한 척수손상-기능실현평가지수 추정식은 신뢰도와 타당도가 높았으며, 이 추정식을 이용하여 만성 척수손상환자의 기능변화 및 재활치료효과를 객관적으로 측정하는데 효과적임을 알 수 있었다. 또한 SCIMⅡ 평가 점수의 결과 해석을 위해 개개인의 SCIMⅡ 점수를 손상레벨별로 비교할 수 있는 기준 자료가 될 수 있음을 알 수 있었다. Objective:The purpose of this study was to produce a regression equation from the preliminary version of the Spinal Cord Injury Ability Realization Measurement Index(SCI-ARMI) for the chronic phase of SCI patients, and to examine the reliability and validity of the estimation. Methods:The subjects consisted of 66 chronic SCI patients with ASIA impairment grades A, B and C, who were admitted in the Sahmyook Rehabilitation Center from January to June, 2006. The patients were assessed with an ASIA motor score in order to measure their neurologic motor impairment, and an SCIMⅡ_to measure their functional abilities at admission and discharge. To examine the reliability and validity of the formula, the calculation of SCI-ARMI was analyzed using the Pearson correlation coefficient. Results:The following results were obtained from this study. 1. ASIA motor scores were statistically significant effect to SCIMⅡ scores. 2. As a simple linear regression of the predictive ability of SCIMⅡ scores, a preliminary formula for the calculation of SCI-ARMI was obtained. The SCI-ARMI estimation is as follows. Total SCI-ARMI = 100 × total SCIMⅡob/{13.419+1.127(Motor Score)} (R=.966, SEE=1.747, R=.933) 3. Formula based SCI-ARMI values were highly-significantly correlated with SCI-ARMI values based on its definition(r=.723, p<.05). 4. Motor scores were not significantly correlated with formula-based SCI-ARMI values and SCI-ARMI values based on its definition on discharge. 5. Formula based SCI-ARMI values were not significantly correlated with patients' age, cause of injury, rehabilitation duration, impairment level, and injury severity(p>.05). Conclusion:The results of this study indicate that a formula for the calculation of SCI-ARMI using the chronic phase of individual SCI patients' SCIMⅡ scores and ASIA motor scores is highly valid and reliable, suggesting that SCI-ARMI can be used to examine functional changes and the effects of rehabilitation treatment outcome objectively quantitatively in chronic SCI patients.

마두령(馬兜鈴)이 혈관(血管) 평활근(平滑筋)에 미치는 영향(影響)

김형창 ( Hyung Chang Kim ),류도곤 ( Do Gon Ryu ),한종현 ( Jong Hyun Han ),이호섭 ( Ho Sub Lee ) 대한경락경혈학회 2000 Korean Journal of Acupuncture Vol.17 No.1

Fructus Aristolochiae has been used in Korea for many centuries as a treatment for various disease. The purpose of the present study is to determine the effect of Fructus Aristolochiae on norepinephrine(NE) induced blood vessel contraction in rabbits. Rabbit(2 kg, male) were killed by CO2 exposure and a segment (8-10mm) of each rabbit was cut into equal segments and mounted in a tissue bath. Contractile force was measured with force displacement transducers under 2-3 g loading tension. The dose of norepinephrine(NE) which evoked 50% of maximal response (ED50) was obtained from cumulative dose response curves for NE (10(-6)~10(-3)M). Contractions evoked by NE (ED50) were inhibited significantly by Fructus Aristolochiae in abdominal aorta and femoral artery. Fructus Aristolochiae inhibited the relaxation pretreated propranolol and L-NNA in femoral artery. But Fructus Aristolochiae did not effect the relaxation pretreated ODQ in femoral artery and abdominal aorta. These results indicate that Fructus Aristolochiae can relax NE induced contraction of rabbit blood vessel selectively, and that this relaxation relates to nitric oxide synthesis and sympathetic action.

竹瀝이 血管에 미치는 영향

김형창(Hyung Chang Kim),경은호(Eun Ho Kyung),나한일(Han Il Na),이계복(Gye Bok Lee),정미란(Mi Ran Jeong),한종현(Jong Hyun Han) 한의병리학회 2004 동의생리병리학회지 Vol.18 No.2

數動 韓藥材가 血壓 및 局所腦血流量에 미치는 影響

金炯昌,黃勁澤,韓宗鉉 대한동의병리학회 2000 동의생리병리학회지 Vol.14 No.1

腦血管 疾患인 中風은 中樞神經系에 影響을 미치는 成人病중 다른 疾患에 비해서 致命的이며, 그 後遺症 또한 深刻한 社會的 問題를 惹起하는 重要한 問題이다. 現在 이러한 腦血管疾患은 歐美 先進 各國에서는 물론 우리나라에서도 發病 頻度나 이로 因한 後遺症 및 死亡率이 繼續 增加하고 있어 各種 癌으로 因한 死亡을 除外하고는 單一臟器의 疾患으로서는 단연 首位를 차지하고 있으나 이에 대한 뚜렷한 豫防 및 冶療法은 물론 根源的인 病因論 마저 제대로 確立되어 있지 못한 實情이다. 中風의 治療法으로는 鍼과 藥을 使用하였으며, 주로 理氣·順氣에 역점을 두었다. 中風의 治療 方法이 이러하기에 理氣之劑에 屬하는 藥物중 香附子와, 厚朴, 檳 및 白荳 를 選擇하여 效能를 살펴보았다. 그 結果 香附子, 厚朴, 檳랑 및 白荳寇는 局所腦血流量을 增加시켰으며 血壓은 濃度에 依存하여 低下하는 것을 알 수 있었으며, 앞으로 理氣之劑가 中風 病者의 豫防 및 治療에 있어 血壓의 低下 및 腦 保護를 할수 있는 것이라 思料되며, 또한 多樣한 活性을 나타내는 약물들에 대해서 實驗을 繼續 進行하여 機轉을 밝혀야 할 것으로 思料된다. Oriental medicine prescription has used for the treatment of various clinical symptoms associated with cerebral apoplexy. However, single herb drug does not used cerebral apoplexy and there mechanisms of action have not been defined, and it is not yet known what effects they have on the hemodynamics of cerebral circulation. The study was aimed to investigate the effect rhizoma cyperi(RC), cortex magnolia(CM), semen arecae(SA) and fructus amomi cardamomi(FAC) on the vascular systems including changes in blood pressure (BP), and regional cerebral blood foow (rCBF) and of male Sprague-Dawely rats. The changes in rCBF were determinated by laser-Doppler flowmetry. 1. Blood pressure was decreased by RC, CM and FAC in a dose-dependent manner. 2. Significantly Blood pressure was decreased by SA in a dose-dependent manner. 3. Significantly rCBF was increased by RC, CM, SA in and FGC in a dose-dependent manner. These results suggest that RC, CM, SA and FGC sauses a diverse response of blood pressure and regional cerebral blood flow(rCBF).

스텝 펄스파를 사용하는 캐스케이드 인버터에서 스위치의 간단한 도통각 계산법

김형창(H.C. Kim),김태진(T.J. Kim),강대욱(D.W. Kang),현동석(D.S. Hyun) 전력전자학회 2003 전력전자학술대회 논문집 Vol.2003 No.7(2)

In recent years, the multilevel inverter synthesizing the output voltage with step pulse has been widely used as a solution for high power and high voltage applications, Tills paper proposes a simple method to obtain the conducting angle It is calculated by using voltage-second areas of the divided reference voltage according to the output voltage levels and these areas have influence on output step pulse waves It is possible to reduce an amount of calculation because it is not required to solve the simultaneous equations by an Iterative method Also, the proposed method can get the conducting angle by means of on line,<br/>

芍藥甘草湯의 效能에 관한 연구

이윤석,김형창,황의현,조성균,임인규,한종현 대한동의생리학회,대한동의병리학회 2003 동의생리병리학회지 Vol.17 No.2

Paeoniae Radix, Glycyrrhizae Radix and Jakyakgamchotang have been used in Oriental Medicine for many centuries as a treatment for various disease. The purpose of the present study is to determine the effect of Paeoniae Radix, Glycyrrhizae Radix and Jakyakgamchotang on norepinephrine(NE) induced contraction of isolated rabbit femoral artery. Rabbits (2.0kg, female) were killed by CO_2 exposure and a segment (8-10mm) of the aortic ring from each rabbit was cut into equal segments and mounted 'in pairs' in a tissue bath. Contractile force was measured with force displacement transducers under 1.5g loading tension. The dose of NE which evoked 50% of maximal response (ED_(50)) was obtained from cumulative dose response curves for NE (10^-(7)~10^(-4)M). Contractions evoked by NE (ED_50) were inhibited significantly by Paeoniae Radix, Glycyrrhizae Radix and Jakyakgamcho-tang. The mean percent inhibition of NE induced contraction was 83.9% (p<0.01) after 150㎕/㎖ Paeoniae Radix, 101.1%(p<0.01) after 150 ㎕/㎖, Glycyrrhizae Radix and 107.3%(p<0.01) after 150㎕/㎖ Jakyakgamcho-tang, Indomethacin slightly but significantly attenuated the inhibitory effects of Paeoniae Radix. Following treatment with indomethacin, the mean percent inhibition caused by 150㎕/㎖ Paeoniae Radix fell to 16.4% in femoral artery induced by NE contraction. Propranolol, ODQ, and L-NNA did not significantly alter the inhibitory effect of Paeoniae Radix. ODQ slightly but significantly attenuated the inhibitory effects of Glycyrrhizae Radix. Following treatment with ODQ, the mean percent inhibition caused by 150㎕/㎖ Glycyrrhizae Radix fell to 13.0% in femoral artery induced by NE contraction. Propranolol, indomethacin and L-NNA did not significantly alter the inhibitory effect of Glycyrrhizae Radix. L-NNA slightly but significantly attenuated the inhibitory effects of Jakyakgamchotang. Following treatment with L-NNA, the mean percent inhibition caused by 150㎕/㎖ Jakyakgamchotang fell to 13.8% in femoral artery induced by NE contraction. Propranolol, ODQ and indomethacin did not significantly alter the inhibitory effect of Jakyakgamcho-tang. These results indicate that Paeoniae Radix, Glycyrrhizae Radix and Jakyakgamcho-tang can relax NE induced contraction of the isolated rabbit femoral artery, and that this inhibition related to nitric oxide.

菟絲子 의效能에 대한 硏究

진상식,황의현,김형창,김천수,오광수,한종현 한국전통의학연구소 2002 한국전통의학지 Vol.12 No.1

The purpose of this study is to determine the effect of Semen Cuscutae on phenylephrine(PE) and KCI induced contraction of isolated rat thoracic aorta. Contractile force was measured with force displacement transducer under 1.5 g loading tension. Contraction evoked by PE (ED_(50)) was relaxed significantly by Semen Cuscutae. The mean percent relaxing of PE induced contraction was 60.6% (p<0.01) after 300 ㎕/㎖ Semen Cuscutae, but the mean percent contraction of KCI induced contraction was 10.4% (p<0.05) after 300 ㎕/㎖ Semen Cuscutae. Vasorelaxation by Semen Cuscutae was significantly reduced after with and without endothelial cells. Pretreatment of aortic rings with L-NAME (100 μM), a nitric oxide synthase inhibitor, indomethacin (3 μM), an inhibitor of cyclooxygenase, methylene blue (10 μM), guanylyl cyclase inhibitor, propranolol (1 μM), a β-adrenoceptor antagonist, atropine (1 μM), a muscarinic receptor antagonist and diltiazem (10 μM), a Ca^(2+)-channel blocker was recovered the effect aorta. These results indicate that Semen Cuscutae can relax EP induced contraction of isolated rat thoracic aorta and that this increasing contraction related to epithelium and various effect.

Torque Characteristics of Radial Piston Motor with Cam Ring Robe Geometrical Design

Y. J. Jo(조영진),W. G. Jeong(정원경),H. C. Kim(김형창),S. W. Ji(지상원) 유공압건설기계학회 2022 유공압건설기계학회 학술대회논문집 Vol.2022 No.6