당산철교의 동적 해석

신효철(Shin Hyo Chul),이창환(Lee Chang Hwan),오동권(Ou Dong Kwon),이성철(Lee Sung Chul) 대한토목학회 1997 대한토목학회 학술발표회 논문집 Vol.1997 No.1

저슬럼프 콘크리트의 개질유황 사용성에 대한 검토

신효철 ( Hyo Chul Shin ),김규용 ( Gyu Yong Kim ),김정현 ( Jung Hyun Kim ),김진만 ( Jin Man Kim ) 한국건축시공학회 2015 한국건축시공학회 학술발표대회 논문집 Vol.15 No.2

In this study, fresh state properties and mechanical properties of low slump concrete which is applied to road pavement have been evaluated by mixing modified sulfur. As results, influence of mixing modified sulfur on the workability was low. Also, compressive strength, and flexural strength tend to decrese with increasing addition rate of modified sulfur. However compressive strength, and flexural strength of modified sulfur concrete were equivalent with that of plain concrete.

철도터널 파쇄대 절리 방향과 붕괴유형 상관성 분석

신효철(Hyo-Chul Shin),신민호(Min-Ho Shin),조국환(Kook-Hwan Cho) 한국철도학회 2013 한국철도학회 학술발표대회논문집 Vol.2013 No.11

터널굴착 시 단층파쇄대와 같이 불량한 암반이 존재할 경우 터널보강 및 시공에 많은 어려움이 있고, 이에 따른 보강, 보조공법이 나날이 발전되어가고는 있지만 아직까지 여러가지 이유로 인해 공사 중 붕괴 사고가 종종 발생되고 있다. 본 논문은 철도터널 시공 중 파쇄대 지역의 붕락 중 측벽부 붕락에 대하여 설계 적용된 일반 물성치하에서 존재된 파쇄대 방향 변화가 터널붕락 유형과 어떠한 상관성이 있는지, 실제 발생한 파쇄대 방향 49도 일 때 붕괴양상의 검정을 통하여, 30도 45도 60도 75도 일 때 파쇄대 방향변화를 통하여 터널의 파괴 유형을 도출하였다. 연구결과, 파쇄대 각도와 파괴영역과의 상관관계, 최대 파괴 깊이 및 방향을 제시하였으며 연구결과를 바탕으로 파쇄대의 존재에 따른 대책수립이 가능할 것으로 판단된다. If there is a fracture zone such as poor rock tunneling, many difficulties were encountered in the tunnel reinforcement and construction. Thus, reinforced and sub method of construction is continuously developed. But, collapse accidents during construction still are often occured by various reasons. In this paper, Assuming the direction of the fracture zone change and side wall of tunnel collapse type, the destruction types of the tunnel are derived through the verification of collapse patterns when incurred direction of the fracture zone is 49 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees each other. As a result, there is suggested that a relationship between the fracture angle and zone, the maximum fracture depth and direction. According to this study, it is expected that measures to establish from the existence of fracture zone.

Portfolio 理論에 관한 小考

呂東吉,申孝哲 啓明大學校 産業經營硏究所 1983 經營經濟 Vol.16 No.1

Fundamentally, it is impossible for an investor to expect perfect optimization of decision making under uncertainty, But ultimately it is possible for an investor to pursue optimization based on limited rationality. From those assumptions we can induce following conclusion. Marbowitz Model enabled it possible to establish portfolio indicating optimum leturn-risk level in efficient frontier. Standard deviation is the best means of measuring the risk on stock and portfolio. Sharp Model classified the risk of securities into systematic risk and unsystematic risk. Unsystematic risk can be reducced to Zero by means of appropriate variations, but on the contrary, systematic risk (β coefficient) cannot be reduced perfectly. Lintner Model explained the equity theory of capital market premising dominance principle, homogenious expectations or predictions of an investor, and perfect capital market. Farra Model showed the choice standard of the best portfolio in efficient portfolio. In securities investment decision, it is not the inter-relation between expected return and risk of security, but the interrelation (coveriance) of portfolio securities. Therefore, diversifiable securities are preferable to investors. Efficient Portfolio combination bas small variance in the same level expectation or has high expectation in the same variance. level A reasonable investor can decide the best portfolio by means of an indifference curve.

Lidocaine의 산성도가 경막외 마취에 미치는 영향

이원형,신효철,신용섭 충남대학교 의과대학 지역사회의학연구소 1990 충남의대잡지 Vol.17 No.1

The affective factors on regional anesthesia are lipophilic-hydrophilic balance of local anesthetics, protein binding, hydrogen concentration, structure of intermediate chain, and etc. Local anesthetics in solution exit in a chemical equilibrium between the basic uncharged form(B) and the charged cationic form(BH^+) by Henderson-Hasselbalch equation(PH_a=PK+log[B]/(BH^+)). The increasement of uncharged form brig about rapid onset, good quality, and long duration of anesthesia. Eight patients in group Ⅰ were given 2% lidocaine 21.7ml with 1: 200,000 epinephrine(pH 5.1), and eight patients in group Ⅱ were given 2% lidocaine 20ml with 1: 200,000 epinephrine added NaHCO_3 1.7ml(pH 7.2) to determine the epidural analgesic effect of the pH-adjusted solution. The results are summerized as follow 1. The onsets of analgesia and surgical anesthesia were significantly rapid in group Ⅱ. 2. The levels of analgesia were raised more rapidly in group.

수술중 수혈환자의 임상적 고찰 (Ⅱ)

최세진,신효철 충남대학교 의과대학 지역사회의학연구소 1990 충남의대잡지 Vol.17 No.2

Over the past several decades, blood and blood components have been increasingly recognized as medication rather than innocuous fluids used to replace modest blood lose at operation. But blood transfusions have the potential for many harmful side effects. Therefore, modern hemotherapy practice focuses on the benefits and risks, along with profer dosage, items with which blood component transfusion is concerned, when blgod transfusions are indicated. only that fraction of the blood that the patient requires should be administered. Most blood donations are separated into components after collection : red blood cells, platelet concentrates, and/or cryoprecipitates and plasma. No longer is "fresh whole blood" an appropriate response to a hemotherapeutic problem. This study was undertaken to evaluate transfusion according to surgical department, sex, preoperative hemoglobin values, blood type, transfusion amounts and blood component therapy. 3847 transfused patients among the total 21371 surgical cases done at the Chung-Nam National University Hospital from 1985 to 1989 were reviewed. The results are summerized as follow : 1. The numbers of transfused patients among the 21371 operative cases were 3847 cases (18%). 2. The number of male transfused was greater than that of female and third decade patient was the greatest incidence among the transfused patients. 3. Mostly hemoglobin value in preoperative state was maintained more than 10g/dl. 4. The blood types of transfused blood were in the great order of A. B, O, AB type. 5. The percentage of one pint transfusion was gradualy decreased and 2-5 pint transfusion was greatest percentage namely 57.94% 6. As the amount of blood transfused was increased, the percentage of blood compoent therapy was increased, and mixed case of PRC and FFP was the greatest incidence. 7. The greatest percentage of blood component therapy was in the cases of the orthopedic surgical operation.

雜犬에서 Isoflurane 마취시 Epinephrine 용량에 의해 유발된 부정맥의 비교연구

최세진,최광희,신효철 충남대학교 의과대학 지역사회의학연구소 1990 충남의대잡지 Vol.17 No.2

Isoflurane has been known to reveal relatively stable hemodynamic effects on cardiovascular system. So many anesthesiologist recommand it as the anesthetic choice for cardiovascular surgery. Epinephrine injection for surgical hemostasis during general anesthesia especially exogenous epinephrine injection with halothane & cyclopropane induced the arrhythmias. The author performed the experimental study to evaluate the arrhythmias and cardiovascular effects during 1% isoflurane anesthesia, when diluted solution of epinephrine intravenous injected. Systolic Blood Pressure, Diastolic Blood Pressure, Mean Arterial Pressure, Heart Rate, and presence of arrhythmia were measured. 1. Arrhythmias were few and transient in diluted epinephrine concentration increase. 2. SBP, DBP, MAP were increased in diluted epinephrine concentration increase. 3. Heart rate were decrease at systolic pressure peak level.

Effects of Aprotinin for Changes of Hct, Serum Protein, Polymorphonuclear Leukocyte Count, and Serum Complement 3 and 4 following CPB

Lee, Jung-Un,Shin, Hyo-Chul 충남대학교 의과대학 지역사회의학연구소 1989 충남의대잡지 Vol.16 No.2

Bradykinin은 trypsin에 의해 kininogen으로부터 유리되는 내인성 peptide로써 강력한 혈관 확장과 혈관 투과성을 증가시키는 작용을 가지고 있으며 이것은 정상적으로 대부분이 단 한번의 폐순환으로 혈중에서 소실되나 체외 순환을 시행 할 경우 혈중에 축척되어 저혈압 혈관 투과성의 증가 및 정맥혈 회귀(venous return)량의 감소 등을 유발하여 체외 순환에 따른 문제점을 야기 시키고 있음을 주지의 사실이다. 저자는 소의 췌장 및 폐에서 추출하여 정제 농축시킨 다가의 야기 시키고 있음을 주지의 사실이다. KIU/Kg을 투여하여 체외 수혼 전 후의 혈장 단백질, hematocrit, 다핵백혈구 수, 혈소판 수 및 혈중 보체 3.4의 변화를 관찰하여 다음과 같은 결과를 얻었다. 1. 체외 순환 전 후의 혈장 단백질 및 hematocrit는 대조군에서는 현저히 (p<0.01, p<0.05) 증가하였으나 aprotinin 투여군에서는 변화가 없었다. 2. 다핵벽혈구 수는 체외 순환 시작 후 현저히 (p<0.05) 감소하여 체외 순환 동안 계속 감소한 상태로 유지되었다. aprotinin 투여군에서도 역시 감소하였으나 대조군에 비해 그 감소 정도가 작았다. 두 군 모두에서 체외 순환 후 반발성 백혈구증다증을 나타내었다. 3. 혈소판 수도 체외 수환 시작 후 현저히(p<0.05) 감소하여 체외 순환 중 계속 감소한 상태로 유지되었다. aprotinin 투여군에서도 역시 감소되었으나 그 정도가 작았다. 두 군 모두에서 체외 순환 후 혈소판 수가 증가하였다. 4. 혈중 보체 3, 4는 양 군에서 모두 체외 순환이 시작됨에 따라 감소하여 체외 순환 후 2시간까지 낮게 유지되었으나 보체 4보다 3이 대조치에 비하여 통계적으로 유의하게 (p<0.05) 감소하였다. 5. 출혈시간은 aprotinin 투여군에서보다 대조군에서 더 증가하였으나 통계적인 유의성은 없었다. 다핵백혈구의 폐격리 (pulmonary sequestration)는 양군에서 비슷하였다.