분만과 진통중 지속적 경막외마취와 간헐적 경막외마취의 비교연구

손수창,최세진,최희자 충남대학교 의과대학 지역사회의학연구소 1995 충남의대잡지 Vol.22 No.1

Thirty one healthy women, ASA physical status 1-2 with an uncomplicated pregnancy and single fetus in vertex position were given lumbar epidural analgesia. After the initial injection of 0.25% bupivacaine(with 1:400,000 epinephrine) 8-10ml and fentanyl 50-75㎍, the parturients were divided randomly assigned to either continuous infusion group or intermittent infusion group. Intermittent infusion group received 0.125% bupivacaine (with or without 1 : 800,000 epinephrine) 10-12ml and fentanyl 50-75㎍. Continuous infusion group received 0.125% bupivacaine and fentanyl 2 ㎍/ml at a rate of 8-10ml/hr. There was no significant difference between two groups in duration of epidural infusion, duration of the second stage of labor, duration of pushing, motor block at delivery, mode of delivery and Apgar scores. 15 of 16(94%)women in the intermittent group, and 11 of 12(92%)women in the continuous group had analgesia of excellent or good quality. The number of refill-doses was 1.8±1.5 in intermittent group and 1.6±1.5 in continuous group, nonsignificantl different. The total dose of bupivacaine administered during epidural analgesia was more in continuous group than in intermittent group significantly. However mean hourly dose of bupivacaine and fentanyl were similar in both groups. It is concluded that the maintenance of epidural anangesia by continuous infusion is a safe and reliable method and may be advantageous and less labor intensive than the traditional intermittent technique.

고감도 에어백용 실리콘 가속도센서의 설계

손미정,김경기,서희돈,최세곤 嶺南大學校 工業技術硏究所 1997 工業技術硏究所論文集 Vol.25 No.1

This paper presents the high sensitivity silicon piezoresitive accelerometer for possible use in an automotive airbag system. Two basic types of silicon piezoresitive accelerometers(bridge-type and cantilever-type)have some problems in the sensitivity and resonance frequency. The bridge-type has high resonance frequency and low sensitivity, but the cantilever-type has everse property. in order to improve the properties of the silicon piezoresistive accelerometer, we propose a new type of silicon accelerometer that have three beams. The proposed structure is that two beams are located at the each comer of the right side, and the other is at center of the left side. The optimized overallsize of the new type accelerometer is more smaller than two basic types of accelerometer. In the simulated reselts using analytical formelae and finite-element modeling(FEM), It's maximum stress is 26MPa and resonance frequency is 3250Hz for 50 G acceleration, respectively. The proposed structure is expected to be applied to much wider use automotive airbag application than the other structures.

Character Agent와 가상현실 기법을 이용한 웹사이트 개발에 관한 연구 : 기존 사이트 분석을 중심으로

손세환,김명희,김종기 동서대학교부설연구센터 2001 연구센터논문집 Vol.4 No.1

Web environment had developed with haste degree than other business. Research about information transmission method in web environment is gone in many-sidedness degree these day. Field that attract user's interest latest among it is character and virtual reality. specially, virtual reality begins in VRML and much skill is appearing to intel's 3D skill recently. But, eminent skill is site that is not to speak that is standard. Users are applying various imagination skill and sites of several form are appearing. Wish to analyze finding virtual reality site that appear recently and is consultable in site model development.

도장작업시 유해인자들의 노출수준과 작업환경관리실태

이세기,문덕환,이채관,황용식,선병관,손병철,김대환,이창희,김휘동,이채언 인제대학교 백병원 2002 仁濟醫學 Vol.23 No.5

Objectives: For the purpose of preparing the fundamental data and assessing the status of exposure level of chemical substances in painting process. Methods and Materials: The author determined the concentration of organic solvents, lead(Pb), Chromium(Cr), and Toluene-2, 4-diisocyanate(TDI) in air of painting process to 90 industries classified by 15 types of manufacturing industry during a period from Jan. 1st 2001 to Dec. 31st 2001. Results: The results were as follows: 1. The geometric mean level of each chemical substance was 0.1706 ppm for exposure index in organic solvents, 0.0019㎎/㎥ for Pb, 0.0024 ㎎/㎥ for Cr, and 0.0004ppm for TDI, respectively. 2. The exposure level of each chemical substances by type of painting was the highest in dipping and brush painting for organic solvent, in spray-painting for TDI, and in spray gun-painting for Pb and Cr, respectively. 3. The exposure level of each chemical substances by type of local ventilation equipment was higher in enclosed and booth type for organic solvents. Cr, and TDI, and in exterior type for Pb, respectively than those of other types. 4. The exposure level of each chemical substances by type of hazardous material arresting media was higher in using water for organic substances, in using bag filter for Pb, TDI, respectively than those of other types. Conclusion: According to above results, this study suggests that the exposure level by type of industry exceeded the exposure level in wooden furniture and metal furniture manufacturing industry for organic solvents and Pb, respectively.

일괄공정 압저항혈 압력센서의 특성

서희돈,이동원,손미정,최세곤 嶺南大學校 工業技術硏究所 1998 工業技術硏究所論文集 Vol.26 No.1

This paper describes structural characteristics of three kinds of piezoresistive pressure sensors, which include wheatstone-bridge type, center-boss type and single-element type, fabricated on one-chip by batch process. In order to optimize device dimensions with respect to the desired characteristics, analytical formula and finited-element modeling(FEM) are used in design process. In experiments the pressure sensitivity of wheatstone-bridge type is about 2.2㎷/V·㎪. The fabricated center-boss pressure sensor has improved in the characteristics as linearity at low pressure, and sensitivity is about 2.415㎷/V·㎪. In single-element type with a four-terminal gauge using shear stress, the maximum sensitivity about 0.4㎷/V·㎪ appeared at the center of the diaphragm with the 3:1 of the length : width ratio. this type is very appropriate method to minimize the temperature dependance of the offset voltage and sensitivity, because the fabricated sensors reduce the offset of themal stress and mismatch of piezoresistros as compared with the wheatstone-bridge type.

고도정수처리 공정에서의 천연유기물질 특성변화 및 소독부산물 전구물질의 제거특성 평가

노재순,손희종,박은주,황영도,최동훈,배석문,신판세 慶星大學校 環境問題硏究所 2002 環境硏報 Vol.12 No.1

In this research the movement and apparent molecular weight distribution of hydrophilic/hydrophobic organic matters in advanced water treatment process were investigated using the raw water of Maeri area, located in downstream of Nakdong river, and the variation of the disinfection by-product formation potential was also investigated. In the raw water used in experiments, the content of BDOC (biodegradable dissolved organic carbon) in dissolved organic carbon (DOC) was about 39%, and this value is far above a normal, Pre-ozone treatment showed an increase of 40% in the BDOC content, and this means that biodegradability was remarkably increased by ozone treatment BDOC concentration in BAC treated water was 0.09 mg/L, which means 84% of BDOC removal rate compared with that in post-ozone treated water. The variation of chlorine disinfection by-product formation potential in each process unit of water treatment process was analyzed. TOXFP concentration in raw water was 449 ㎍/L, and the contents of THMFP and HAAFP among TOXFP were 24% and 23%, respectively. The removabilities of these materials BAC process had an order of TOXFP > HAAFP > THMFP. BAC process was less effective for THMFP than others. The distribution of hydrophilic organic matters were evaluated in each treatment process. Hydrophilic and hydrophobic matters in the raw water had a ratio of 50 : 50, and the ozone treatment decreased the content of hydrophobic matters. The BAC treatment made the ratio 85:15. These mean that the removal of hydrophilic matters is more difficult than that of hydrophobic materials in water treatment process. In addition the portions of humic and fulvic acid in hydrophobic matters were analyzed. Fulvic acid a large portion among hydrophobic matters in the raw water, and the portion was 78%. Ozone treatment was more effective on the removal of fulvic acid than humic acid. After BAC treatment, the concentration of residual fulvic acid was high than humic acid. Chlorine disinfection by-product formation for hydrophilic and hydrophobic mattrts was compared in each process unit. in the raw water TOXFP and THMFP formation for hydrophobic matter was higher, and HAAFP was highly formated for hydrophobic matter. After post-ozone or BAC treatment, chlorine disinfection by-product formation has high potential for hydrophobic matters. Comparing humic and fulvic acids, chlorine disinfection by-product formation potential was higher for humic acid than for fulvic acid in all processes. In the comparison of the reactivity with chlorine disinfection by-product per unit DOC, THMFP and DOXFP showed higher reactivity with hydrophobic matter than with hydrophilic matter in all processes, and HAAFP was highly reacitive with hydrophilic matter. Apparent molecular weight distributions of organic matters were investigated in each process step.The content of low molecular weight organic matters less than 1000 Da in DOC was high in all processes except raw water, but molecular weight organic matters more than 1000 da was higher than molecular weight organic matters less than 1000 Da in the formation potential of chlorine disinfection by-product.

세계산 Rumiceae Dum.족 (마디풀과)의 진화계통학적 연구

홍석표,손세희 경희대학교 자연과학종합연구원 1999 자연과학논문집 Vol.5 No.-

세계산 Rumiceas Dum.족을 구성하는 4속(Rumex속의 4절, Rheum속의 3절, Oxyria속, Emex속) 분류군간의 진화적 유연관계에 대한 가설을 제공하고, 형질진화의 경향을 밝히기 위한 분자분식(cladistic analysis)을 수행하였다. 최소절약의 원리를 이용하여 24개의 두단계 혹은 다단계 형질을 분석하였다. 분석 결과 계통수의 길이는 36, 일관성지수는 0.714, 보존지수는 0.843인 4개의 등가질약 계동수가 산출되었다. Rumex속의 4개 절과 Emex속은 하나의 Clade를 구성하며, 이는 여러 개의 공유파생형질(익상수과, 오용 존서, 만곡의 배, 등)에 의해 지지된다. 결과적으로 Emex속은 Rumex속의 하나의 절(section)로 처리함이 타당하다. 또한 Oxyria속은 3개의 독립파생형질(화사수:2개, 렌즈형의 수과, 4개의 화피핀)에 의해 다른 속과 잘 구별되었다. Cladistic analysis of four genera (4 sections of the genus Rumex, 3 sections of the genus Rheum, Oxyria and Emex) of the tribe Rumiceae Dum. was undertaken to provide hypotheses about evolutionary relationships and to elucidate patterns of character evolution. A set of 24 binary and multistate morphological characters were analyzed using maximum parsimony algorithms. With the given data set. four equally parsimonious trees 36 tree length with a consistency index 0.714 and a retention index of 0.843 were produced. Four sections of Rumex and Emex came together as one clade and was strongly supported by several synapomorphies (e.g.. winged achene. trichome present. curved embryo. etc.). Thus: it is considered that Emex is better treated as one of section in Rumes. Oxyria is also well distinguished by its automorphic characters (by having 2 styles. lenticular achene. 4 perianth segment number).

최근 10년간 마취에 관한 임상적 고찰 (Ⅲ)

조현숙,김윤희,손수창,김혜자,최세진 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

To evaluate the specificity and the historical trends of the anesthetic agents and anesthetic methods used in Chungnam national university hospital, anesthetic experiences of 53,291 in total performed at Chungnam national university hospital from January 1987 to December 1996 were analized statistically and clinically according to age, sex, surgical department, physical status, elective to emergency surgery, premedicants, induction agents, anesthetic methods, main anesthetic agent, anesthetic technique and muscle relaxants. The results were as follows : L The number of cases has been steadily increased in annually. 2. The distribution of the number of patients according to the age were cases 37,309(70.02%) in the group of 13-60 years. 3. There were 27,448 male (51.5%) and 25,843 female (48.5%) cases. 4. 9,208 cases (17.27%) were OB-GY, 9,162 cases (17.19%) in general surgery, 7,936 cases(14.89%) in orthopedic surgery, and 6,079 cases (11.4%) in ENT in order of numbers. 5. According to the ASA classification of physical status , most of the cases were belonged to the class 1 (38.69%) class 2 (40.33%) class 1E (5.52%) class 2E (5.71%). Almost cases were relatively in good physical status. 6. The number of elective to emergency was 7,833 (89.76%), to 5,458 (10.24%) cases. 7. As premedicants, a group of glycopyrrolate (35.20%) was given most frequently. 8. Thiopental sodium has been mainly used for intravenous induction agent. 9. General anesthesia has been used as main method of anesthesia. 10. Enflurane was the most commonly used anesthetic agent. 11. Vecuronium was the most commonly used non-depolarizing muscle relaxant.

생체신호처리용 ASIC 칩 개발

배용욱,박차훈,서희돈,최세곤 경북대학교 센서기술연구소 1998 센서技術學術大會論文集 Vol.9 No.1

The biotelemetry system transmits monitored physiological signal from multiple subjects to an electrical instrument at remote place where this information can be observed via electrical or optical link. In this paper, we developed an optical linked telemetry system which can transmit 6-channel physiological signals from 4 subjects, simultaneously. The proposed telemetry system is fabricated with Altera FPGA chip(EPM7128LC84-20) and 0.8μm CMOS n-well process technology. We designed a All-Digital PLL to synchronize with the external measurement system which consisted of a command signal transmitter and a telemetry signal demodulator. The operation characteristic of a All-Digital PLL is superior than an enforced synchronization oscillator which consisted of negative elements and a comparator. The required time to synchronize with a external measurement system at the maximum phase error is about 10.3ms. The novel external measurement system is implemented with Altera FPGA chip (EFM7096LC84-15).

Epinephrine-induced lactic acidosis in orthognathic surgery: a report of two cases

Hee-Won Son,Se-Hun Park,Hyun-Oh Cho,Yong-Joon Shin,Jang-Ho Son 대한구강악안면외과학회 2016 대한구강악안면외과학회지 Vol.42 No.5

Submucosal infiltration and the topical application of epinephrine as a vasoconstrictor produce excellent hemostasis during surgery. The hemodynamic effects of epinephrine have been documented in numerous studies. However, its metabolic effects (especially during surgery) have been seldom recognized clinically. We report two cases of significant metabolic effects (including lactic acidosis and hyperglycemia) as well as hemodynamic effects in healthy patients undergoing orthognathic surgery with general anesthesia. Epinephrine can induce glycolysis and pyruvate generation, which result in lactic acidosis, via β2-adrenergic receptors. Therefore, careful perioperative observation for changes in plasma lactate and glucose levels along with intensive monitoring of vital signs should be carried out when epinephrine is excessively used as a vasoconstrictor during surgery.