경량 고강도 Mg-Zn계합금의 조직과 내식성에 관한 연구

안효준,남태현,임수근,안인섭,허보영,김기원 慶尙大學校 1995 論文集 Vol.34 No.1

The purpose in this study is to develope of high strength and corrosion reistant Mg-Zn system alloys by controlling microstructures and by adding of Cu elements. To produce optimum tesile strength,it is imperative to obtain effective grain refinment during casting. Optimal condition for grain size refining effect was obtained at the minmum composotion of 2wt% Cu or 1.5wt%So addition to Mg-6wt%Zn alloy.Age hardening behavior was experimented at the optimal compositions of the Mg-6wt%Zn, Mg-6wt%Zn-2wt%Cu and Mg-6wt%Zn-1.5wt%Si. The hardeness increment due to age hardening was at the Mg-Zn-Si alloy system. The improvement of corrosion resistanece by the addition with Cu is related to and increasing Zn/Cu ration in the intermatallic particles in the Mg-Zn system.Further improvements obtained by T6 treatment are related to the properties of the Mg-Zn phase,whih acts as a corrosion barrier by precipitating along the grainboundaries.Filiform corrosion observed soon after pit initiation and cellular form of pit propagation later in chloride media are explained in terms of solid solution matrix structure and the properties of air formed oxide.The information obtained from the fundamental research work is utilized in suggesting ways of improving the corrosion resistance of commercial AZ91.

정신분열병 및 정신분열형 장애에 대한 올란자핀의 효과와 안전성

안용민,강대엽,권준수,김창윤,김철응,반건호,신영민,이기철,이동우,이중서,조현상,채정호,김용식 大韓神經精神醫學會 2001 신경정신의학 Vol.40 No.4

연구목적 : 본 다기관 공동임상연구는 국내 환자를 대상으로 새로운 항정신병약물인 올라자핀의 치료 효과와 안전성을 확인하고자 시행되었다. 방 법 : 1999년 7월부터 2000년 3월까지 국내 10개 병원에 방문한 정신분열병 및 정신분열형 장애 105명을 대상으로 비대조 개방 임상연구를 시행하였다. 중등도 이상의 정신병 증상을 지니거나, 부작용으로 약물교체가 필요한 경우 또는 기분장애 증상의 치료가 필요한 환자를 대상으로 하였다. 2∼7일간의 약물 배설기간 후에 1일 10mg의 올란자핀을 투여하였고, 이후로 3∼7일 간격으로 용량을 조절하여 총 8주간 투여하였다. 치료 효과는 PANSS(Positive and Negative Syndrome Scale), BPRS(Brief Psychiatric Rating Scale), CGI(Clinical Global Impression-Severity), MADRS(Montgomery-Asberg Depression Rating Scale), HAM-A(Hamilton Rating Scale for Anxiety)로 판정하였다. 안전성 평가는 자발적인 이상반응 보고, 활력징후와 혈액 검사 및 SAS(Simpson-Angus Scale), BARS(Barnes Akathisia Rating Scale), AIMS(Abnormal Involuntary Movement Scale)척도를 이용하였다. 결 과 : 105명중에서 85.7%인 90명이 8주간의 치료를 완료하였다. 평균 최빈 용량은 일일 16.1(±4.7)mg이었고, 종료시점에서의 BPRS전체 점수가 기저 상태에 비해 40%이상 감소된 반응군은 69.5%이었다. PANSS의 양성 증후군과 일반정신병리 뿐만 아니라 음성 증후군 소척도에서도 유의한 감소를 보였으며, 이 감소들은 치료 초기부터 나타나서 8주간 지속되었다. 43.8%의 피험자가 중등도 이상의 우울증상을 같이 지니고 있었으며, 올란자핀에 의해 MADRS와 HAM-A가 유의하게 감소하였다. 치료 기간 동안에 활력징후에는 뚜렷한 변화가 없었으나 체중은 8주간 지속적으로 증가하였다. SAS와 AIMS는 감소하였으며, 정좌불능증을 제외한 나머지 추체외로 증상의 발생비율도 낮았다. 임상적인 증상이나 징후를 동반하지 않는 ALT/SGPT의 상승을 보였지만 프로락틴을 포함하는 대부분의 혈액 검사상 뚜렷한 이상 변화는 없었다. 결 론 ; 비록 본 임상연구가 비대조 개방 임상연구로서 많은 제한점을 가지고 있지만, 올란자핀이 기존 약물에 내약성을 보이거나 기분증상을 동반하는 정신병에 치료 효과가 있었다. 그리고 기존 항정신병약물 치료시에 문제가 되었던 추체외로 증상과 고프르로락틴 혈증을 포함하는 대부분의 부작용면에서 안전성을 보여 주었다. Objective : This multicenter clinical trial was carried out to investigate the efficacy and the safety of olanzpine for the treatment of Korean patients. Mothod : 105 patients with schizophrenia and schizophreniform disorder, visited at 10 mental or university hospitals, had received an open and non-comparative treatment with olanzapine for 8 weeks. Patients had psychotic or depressive symptoms with the severity above moderate degree or intolerable side effects to previous antipsychotics. After a wash-out period of 2-7 days, 10mg olanzapine was prescribed initially to all the patients, and then the dosage could be adjusted within the range of 5-20mg/day of olanzapine by 3-7 days. Results : 90(85.7%) of 105 patients completed the 8-weeks trial and the mean modal dose of olanzapine was 16.1(±4.7%)mg/day. At the end of the trial, 73 patients(69.5%) were classified as responder, which was defined as 40% or more improvement in BPRS(Brief Psychiatric Rating Scale) score comparing to baseline. There was a significant reduction in the scores of PANSS(Positive and Negative Syndrome Scale)and subscales including negative symptom scores and CGI. Also weekly analysis showed that the reductions in scores were kept on for the whole period of the trial. 43.8% of all the patients had depressive symptoms at the baseline and total scores of MADRS(Montgomery-Asberg Depression Rating Scale) and HAM-A(Hamilton Rating Scale for Anxiety) were also reduced after the trials. Vital signs revealed no clinically significant changes but continuous weight gain was observed during the treatment with olanzapine. The scores of SAS(Simpson-Angus Scale) and AIMS(Abnormal Involuntary Movement Scale) for assessing the EPS(extrapyramidal symptoms)and tardive dyskinesia respectively were significantly decreased and only a few patients reported EPS as adverse events. Although mild and clinically non-significant of ALT/SGPT was observed, most laboratory parameters including plasma prolactin level showed to significant changes during the trial. Conclusions : Although this trial had many limitations because it was a non-comparative and open study, olanzapine showed high efficacy on the positive, negative and depressive symptoms in schizophrenia and schizophreniform disorder.In addition to that, olanzapine showed a substantially favorable safety profile, such as low incidence of EPS and hyperprolactinemia.

Al 7075 合金의 時效硬化處理가 疲勞龜裂傳播에 미치는 影響

안창남,김현철,임병수 成均館大學校 科學技術硏究所 1993 論文集 Vol.44 No.2

An experimental investigation has been carried out to determine the effect of age hard-ening on the fatigue crack propagation behavior and mechanical properties using Al 7075 alloy hot extruded. Fatigue and mechanical property tests have been performed with the specimens prepared in various age hardening heat treatment conditions. Analysis of the experimental results was made to determine the relationship between Δ K_th, yield strength, % elongation and ageing temperature and time.

영양염류 제거를 위한 생물막 공정의 적용에 관한 연구

안승섭,박노삼,이수식,이관영,박상현 한국환경과학회 2000 한국환경과학회지 Vol.9 No.5

In this study, the removal possibility of nutrients of T-P, NH_3-N, NO_3-N, and T-N is examined through a positive experimental study using submerged biofilter of media packing channel method. From the analysis of nutrients removal efficiency for each run of the collected sample, following results are obtained. Firstly, the result of N/P surveying for inflow shows serious value that excess the limit value of 20 as the values are in the range of 12.0∼42.7 and the average is 25.73. Secondly, the highest concentration of the incoming NH_3-N reaches double of the standard since the concentrations of NH_3-N, and NO_3-N for inflow shows 0.06㎎/ℓ , and 2.5∼3.8㎎/ℓ respectively, and the average removal rate which passed the submerged biofilter adopted in this study is a satisfactory level. Next, the average removal rate of T-P of 51.5% shows the possibility of entrophication removal since the removal rate of T-P of 66.8∼68.8% in relative low temperature period of RUN 1∼2 appeared higher than in RUN 3∼6, and T-N shows relatively poor result with the average removal rate of 34.1%. And it is known that the bigger BOD/P and BOD/N are, the more removal rate increases from the examination result of the relation between BOD/P and BOD/N, and the treatment water T-P and T-N to decide the relation with the concentration of organic matters, and thought that the appropriate proportion is necessary for effective removal of nitrogen and phosphorus.

減衰가 있는 振動系에 非線形 動吸振器의 附着時 主應答에 관한 硏究

安贊祐,金賢洙 동아대학교 공과대학 부설 한국자원개발연구소 1985 硏究報告 Vol.9 No.1

The research on the dynamic absorber used for the elimination of vibrations was first attemped by Den Hartog, and for the case of undamped vibratory system, the optimum frequency ratio and the optimum damping ratio can be obtained in a function of mass-ratio only, but for the case of damped vibratory system, the optimum frequency ratio and the optimum damping ratio are not able to be expressed in a function of mass-ratio only, so the optimum frequency ratio and the optimum damping ratio are obtained by the graphical method or the numerical analysis method. Because the systematic method is not yet developed, in this research through the use of the Newton method, the optimum frequency ratio and the optimum damping ratio are obtained in a function of mass-ratio and the ratio of the critical damping coefficient of the principal system vs. the damping coefficient of the principal vibratory system, and by the application of this, the response of the principal system and the response of the case where nonlinear spring is used are obtained. The results are as follwing. 1. As the mass-ratio increases, the response of the principal system decreases in the linear system, but in non-linear system the response of the principal system increases. 2. In the case where non-linear springs are used, the width of band increases as the mass-ratio increases. 3. For the case of non-linear soft spring, the first forced frequency ratio is lower compared with that of the linear system.

단일전력단으로 구성된 AC/DC 풀 브리지 컨버터에 관한 연구

안병무,권순도,김용,백수현 동국대학교 산업기술연구원 2000 산업기술논문집 Vol.11 No.1

본 논문에서는 단일단 AC/DC 폴브리지 토포로지에 적합한 고주파 소프트 스위칭 컨버터응용에 근거를 두고 제안한다. 제안된 컨버터는 입력전류를 불연속 모드로 동작시켜 역률을 개선하며 입력전류의 zero-crossing-point에서의 왜곡을 개선함으로써 고조파를 감소시켜 고역률, 영전압 스위칭, 저잡음과 고효율을 구현한다. 펄스폭 변조 제어방식은 각각의 스위칭과 정류손실을 저감하기 위해 사용되었다. 제안한 컨버터는 IGBT를 전력스위치로서 주로 사용되지는 고전압, 고전력 컨버터응용에 적용할 수 있으며, 실험을 통하여 1.5kW, 30kHz로 동작하는 컨버터를 구현하였다. A single stage AC/DC converter based on a full bridge topology suitable for high frequency soft switching converter applications is proposed. The power factor correction can be achieved by the discontinuous conduction mode(DCM) operation of the input current. The proposed converter gives the good power factor, low line current harmonics. The proposed converter has high power factor, zero voltage switching low noise and high efficency. A pulse width modulation control is employed to reduce the switching and rectification losses respectively. The proposed converter is attractive for high-voltage, high-power applications where IGBT's are predominantly used as the power switches. The principle of operation, features, and design are verified on a 1.5kW, 30kHz, IGBT based experimental circuit.

품종별 부추 추출물의 항산화성 및 항균성

안명수,김현정,서미숙 한국식생활문화학회 2005 韓國食生活文化學會誌 Vol.20 No.2

The antioxidative and antimicrobial activities were carried on the leeks (Allium tuberosun R.) ethanol extracts in order to find out new food functional components. Three species of leeks used in this study were Chinese leek(long type, LL), general leek(medium type, LM), and medicinal leek (short type, LS). Total amounts of polyphenol compounds in LS was shown as the highest (436.60㎎%) value. All of ethanol extracts of these leeks were shown to be had good electron donating ability(EDA) and nitrite scavenging activity. Specially, the ethanol extract of LS(LSEx) had the highest EDA 30.47% and nitrite scavenging activity 77.24% and the lowest was LMEx. The antioxidative activities of these ethanol extracts on the corn germ oil were measured by peroxide values(POV) and conjugated diene values (CDV) storaging for 30 days at 60±2℃. The antioxidative activities of these extracts by POV and CDV were determined as following order as LSEx> LLEx> LMEx. The antioxidative activities of all extracts were presented as high tendency by increasing adding amounts (0.02%〉0.05%〉0.1%). When the antioxidative activities were compared with BHT and a-tocopherol, the degree of the antioxidative activities of these extracts were certified as lower than BHT and higher than a-tocopherol. And also LSEx, LMEx, and LLEx had antimicrobial effects on the several micro organisms, especially the effect on the Pseudomonas aeruginasa was remarkable. While LMEx had shown inhibit effect on most of micro organism used in this study.

Apple mint 용매별 추출물의 항산화 및 항균성에 관한 연구

안명수,김현정 誠信女子大學校 生活文化硏究所 2001 生活文化硏究 Vol.15 No.-

In this work the functionality of apple mint has been stuided. The functionality has been evaluated by testing antioxidative effects and antimicrobial activity. The solvents used were methanol(MeOH), ethylacetate(EtAc), chloroform(CHCl3) and water. The antioxidative effects of various concentration(0.02, 0.05, 0.1%) of the apple mint solvent extracts in the corn oil as substrate were determined by measuring the peroxide value(POV) and conjugated diene value(CDV) of the substrates stored at 60±2℃, for 32 days and the acid value(AV) and conjugated diene value(CDY) of the substrates heated at 180±2℃, for 32 hours. The antimicrobial activityof the apple mint solvent extracts were evaluated by testing the paper disc agar diffusion method. The microrganism used were Staphylococcus aureus 25923(ATCC), Psuedomonas aeruginosa 1750, candida albicans 1940, Escherichia coli 1682, Salomonella typhimurium 2054(isolated strain NO.), vibrio alginolytius 2472 and ratia marcescens 2356. The antioxidative erects of various concentration(0.02, 0.05, 0.1%)of the apple mint solvent extracts in the corn oil as substrate, which had been stored at 60±2℃, for 32 days, was, in decreasing order, as follows : RE 0.1% > RE 0.05% > RM 0.1% > RM 0.05%> RC 0.1% > RC 0.05% > RE 0.02% > RM 0.02% > AW 01% > AW 0.05% > RC 0.02% > AM 0.1% > AC 0.05% > BHT > AE 0.05, 0.1%, AC 0.1% > AM 0.05% > AM 0.02% > RW 0.1% ) AE 0.02% > AC 0.02% > TOC > RW 0.05% > AW 0.02% > CON > RW 0.02% The antioxidative effects of apple mint solvent extracts in the corn oil as substrate, which had been heated at 180±2℃, for 32 hours, was resulted as follows : The antioxidative effect of RM and RE were conciderably higher than that 0.02% BHT and TOC. Except RM and RE, the herb solvent extracts didn't show any antioxidative effect for AV and CDV. The antimicrobial activity of the apple mint and rosemary extracts on several microorganism were resulted as follows : Antimicrobial activity of AM was higher than penicillin, streptomycin and tetracyclin on Psuedomonas. Water extracts didn't show any inhibition on several microorganism. As a result of the above, it was shown that apple mint solvent extracts have good antioxidative and antimicrobial effects. Especially antioxidative effect of AE was higher than BHT and antimicrobial effects was higher than penicillin, streptomycin and tetracyclin On Candida.

노인들이 지각한 사회적 지지가 자기존중감과 건강실천에 미치는 영향에 관한 문헌고찰

安賢洙,徐蓮玉,金貴粉 慶熙大學校 1989 論文集 Vol.18 No.-

Presently, there is the increasing demand for genuine nursing care because of increasing propotion of the elderly population due to extended age. Nursing has rigorously supported the holistic approach to health care. Therefore, it is important to give to the elderly the effective geriatric nursing care thai can improve the quality of their life. Through the literary review, social support is positively associated with self-care practices be found. And an essential component of self-esteem is the value one holds for oneself, it follows that those with more self-esteem would consider it worthwhile to enhance their health status. Social support is physically or psychologically protective, because our health practices, self-concepts, self-evaluations, or ordered functional behaviors depend at least partially upon our social relationships. Consequently, the perceived social support effects on the self-esteem and this interaction follows to practice health behavior. Therefore, what kind of social support does the elderly perceive and need in our country, how perceived social support influences their self-esteem and health practices must continue to be tested. Then as a scientific nursing intervention, it will be given to the elderly social support that be improved their self-esteem. So. the elderly must actively practice self-care and they must maintain the quality of their life.

선박용 엔진 모니터링을 위한 CSMA/CD 프로토콜

안병원,김현수,윤경국 木浦海洋大學校 1998 論文集 Vol.6 No.1

This study is on the development of a monitoring system which can be applied for not only large vessels but also small vessels less than 20 gross tonnage. The Monitoring system consists of many LMU(Local Monitoring Unit)s that collect data from local machinery, a host computer that controls LMU and a stable communication system. In this paper, the industrial computer is used as host computer and that is compotable to IBM PC. GUI(Graphic User Interface) for main program is constructed by the use of HANGUL library and BOLAND C??, so this software package is easy to access to beginners. The LMU is made up from 80C196KC, which consists of CPU, interface, digital input/output, analog input/output and communication. Communication system between the host computer and LMUs is the multidrop configuration using RS-485 method. One master device of industrial computer has the role of host computer and LMUs acts as slave devices. And, more efficient communication system is practicable by the aid of polling method as well as carrier sense multiple access with collision detection(CSMA/CD) protocol.