인터넷 데이터베이스와 온라인 데이터베이스의 검색시스템 검색효율 비교

안태경,김현희 明知大學校 文獻情報學會 1999 文獻情報學論集 Vol.- No.6

인터넷은 상용데이터베이스에 없는 정보와 상용데이터베이스와 거의 같은 정보를 무료로 입수할 수 있는 경우도 있으며 새로운 정보원으로서 중요성을 더해가고 있다. 전문 검색사들은 어떤 때 무슨 온라인 정보원을 이용해야 하는지에 관한 안내가 필요하게 되었다. 따라서 본 연구에서는 먼저 인터넷 데이터베이스와 상용 데이터베이스의 특성을 기존 연구 결과들에서 살펴본 후 두 탐색의 검색 효율성을 측정하기 위해서 이용자에게 의뢰 받은 정보 질문들을 이용하여 실험을 한 후 두 시스템의 탐색 결과를 분석하여 검색소요시간, 최종검색 건수, 적합성 등을 비교해 보았다. 실험 결과, 검색소요시간은 4명의 정보검색사가 6개의 질문 모두를 검색하는데 소요된 시간은 인터넷 평균 14.67분, 상용온라인 평균 4.75분으로 인터넷은 상용온라인 보다 약 3배의 검색시간이 소요되었다. 또한 정보검색속도의 문제는 검색성능과도 관련이 있지만 비용의 문제가 제기 되었다. 적합성 측정에서는 검색자와 질문자 적합성을 측정하였는데 모두 유사한 평가를 하고 있었다. 데이터베이스의 유형별 정보검색의 적합성 측정은 인터넷 데이터베이스에는 수치데이터, 연구기관자료, 디렉토리형 정보원, 기업의 동향분석자료 등에 강한 것으로 나타났다. 상용온라인 데이터베이스는 학술지의 전문(full-text), 학술지의 서지데이터에서 우수한 것으로 적합성이 평가 되었다.

장거리 달리기 선수에서 횡문근융해와 생화학적 지표의 변화에 대한 연구

안선호,최석채,김태현,나용호,송주흥,이영진,조지현,최석준 대한신장학회 2000 대한신장학회잡지 Vol.19 No.5

질소 기체의 다분자층 흡착을 이용한 BN, Alumina 및 Silica-Gel의 동공 크기 분포

안운선,조현우,곽현태,김영진 성균관대학교 기초과학연구소 1988 論文集 Vol.39 No.1

Multilayer adsorption isotherms of nitrogen on hexagonal boron nitride, γ-alumina, and silicagel powders are determined at the liquid nitrogen temperature using a gravimetric adsorption apparatus. The volume(V) of the adsorbed gas are plotted against the statistical thickness(t) of the adsorbed layer, and the t-method area are calculated from the slope of these V-t plots to compare with the BET area. The Frenkel-Halsey-Hill equation are used in calculating the statistical thickness. Pore-size distribution of the adsorbents are determined by using the improved method of pore-size distribution analysis proposed by Ahn et al. The cumulative surface area calculated from the results of these pore-size distribution analysis agrees very well with the BET area and the t-method area.

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.

당뇨병성 신경병증에서 근위부 비골신경전도 검사를 이용한 병태생리학적 접근

김동현,이강건,박종원,박태환,안병철,권오상 대한신경과학회 1998 대한신경과학회지 Vol.16 No.2

응급환자에 대한 맥박산소측정기의 임상적 평가

안철민,이한식,조광현,황태식,김성규 대한응급의학회 1995 대한응급의학회지 Vol.6 No.2

Pulse oximetry is a noninvasive method of measuring blood oxygen saturation even before changes to the cardiopulmonary functions become apparent clinically. Therefore it has been widely excepted in many disciplines as a standard patient monitoring equipment. But its accuracy has been argued at low oxygen saturation levels. To determine the accuracy of the pulse oximetry in the emergency department where the patients presenting with respiratory difficulty are expected to have low oxygen saturation levels. Prospective, cross-sectional, paired measurements of oxygen saturation by two different pulse oxineters(SpO2) against oxygen saturation of arterial blood gas analysis(SaO2) was performed from May 1994 to September 1995 at two different university hospitals. Two pulse oxineters each with its digital probe were applied to the patient for the measurement of SpO2 simultaneously and arterial blood gas was drawn for analysis(ABGA) at the same time to measure SaO2. 98 patients who met the criteria mostly consisted of cardiopulmonary patients. There were no significant differences between mean SpO2(88.1±11.4, 88.2±10.0) of the two pulse oximeters and mean SaO2(88.7±11.4) from the arterial blood gas analysis(p=NS). Strong correlations were found(r=.80). But the regression declined as SaO2 decreased especially SaO2 < 90%. The pulse oximetry is potentially useful in patients with clinical signs of acute hypoxemia and patients receiving interventions that may produce acute hypoxemia, because of their ability to continuously monitor the oxygen saturation. But pulse oximetry along cannot identify the degree of hypoxemia or severity of distress. Therefore patients complaining of respiratory difficulty in an emergengy department, history and physical examination must be performed with pulse oximeter as a guide while backing it up with ABGA.

萬頃江流域에 있어서 井水中의 弗素含量에 관한 硏究

金完泰,安榮根,申和雨,張賢淑 원광대학교 식품약품안전성연구소 1987 食品藥品安全性硏究 Vol.1 No.-

This study is the survey about Fluorine contents in the well water of area of Mankyung River side and water of Mankyung River. The result of this survey is as followings: The water of well in this area contained 0.5∼1.3ppm and it's average value was about 0.8 ppm. The water from Mankyung River contained 0.8∼0.9ppm and it's average value is 0.87ppm. By the regionally sectional survey the well water of the area of Mankyung River side, the well water of Chun-Ju, Iri, Samye, and Kusan contained 0.5∼0.8ppm, but the well water of Baikku area contained 0.6∼1.3ppm. Especially in Baikku area 63% of well contained 0.6∼1.0ppm and 38% of well contained 1.1∼1.3ppm. From the above results one can conclude that the 38% of well water of the Baikku area is troubled one.

국부 안전율을 고려한 유한요소 사면안정해석

이종현,박용원,안태봉 명지대학교 대학원 1997 대학원논문집 Vol.1 No.-

In generally, slole stability analysis has performed by limit by equilibrium method(LEM) Using overall safety factor. Nowadays, however, numerical analysis techniques such as finite element method(FEM) is began to be used in slope stability analysis which considers nonlinear stress-strain behaviour with the advance of computer processor. FEM analysis has merits in reducing the over-or understanding problems of LEM analysis by adapting local safety factor concept and the nonlinearity in stress-strain behaviour of soil and rock. This study performs to develope a FEM computer program for slope stability analysis of soil and/or slope. The newly developed program is testified by the analysis results for several sample cases with existing LEM programs. The minimum safety factors of both analysis methods show good agreement, while the depth of failure surface of FEM analysis is larger than those of LEM analysis.

저혈청 배지에서 인간 전골수세포(HL-60)를 이용한 tPA 생산과 세포사멸기작에 관한 연구

김현구,성기돈,김태호,안주희,함문선,박진서,이현용 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.1

tPA 생산과 세포 사멸의 연구를 하기 위해서 인간 전골수세포가 배양되었다. 연속 관류 배양하에서 최대 tPA 생산량은 324 ng/ml이며 최대 세포 농도는 5.27×10 exp (6) cells/ml였다. Phorbol ester를 넣었을 때 tPA 생산량은 420 ng/ml까지 향상되었다. 형광 현미경으로 관찰했을 때, apoptosis는 세포 배양 초기부터 중반까지 우세했고 빠른 교반 속도에서도 우세했다. 그러나 necrosis는 세포배양 말기와 동결된 세포가 해동 되었을 때 우세했다. HL-60 was cultivated to produce tPA (tissue-type plasminogen activator) and study the mechanism of cell death. Maximum cell density and tPA production were obtained as 5.27×10 exp (6) cells/ml and 324 ng/ml, respectively under perfusion cultivation. tPA production was enhanced to 420 ng/ml in adding 160 nM of phorbol ester. The cells were gradually differentiated to granulocytes rather than proliferation. By Fluorescent microscope, apoptosis was prevailed except the death phase and in high agitation speed, but necrosis was prevailed in thawed cells and during the latter periods of the cultivation. It was also proved that tPA was most produced in apoptosis. To obtain higher tPA productivity, the cells must be maintained in apoptosis, not necrosis phase when the cells were dying.

Propylthiouracil 투여에 의한 갑상선 기능저하 흰쥐 조직에서 알코올 탈수소효소 활성의 변화

백상현,김동선,이창범,박용수,안유헌,김태화,기춘석,강주섭 한양대학교 의과대학 2001 한양의대 학술지 Vol.21 No.2

Background: Thyroid hormone has been known to affect hepatic alcohol dehydrogenase (ADH) activity. Although the liver is the principal site of ethanol metabolism, stomach is also responsible in part for ethanol oxidation. The effects of thyroid hormone on ADH activity in gastric mucosa and other tissues of rats had not been previously examined. Method: The effects of thyroid hormone on liver, stomach, lung, and kidney ADH activities (nM of NADH/min/mg of cytosolic protein) have been investigated in male Sprague Dawley rats treated with propylthiouracil (50 mg/kg) for 14 days. Results: Whereas hepatic ADH activities were not changed by treatment with PTU(42.9(8.6 vs 45.2 (10.1), gastric ADH activities in PTU-treated rats increased by 258.8% of control rat (6.3 ( 0.6 vs 2.2 ( 1.2, p〈0.001). In the activities of other tissues, PTU treatment decreased lung ADH activity by 59.7% of control, and increased kidney ADH activities by 247.1% of control rats. Conclusion: These data suggest that hypothyroidism causes an increase of gastric alcohol metabolism, and that the increase of gastric ADH activity can partly restore the first pass metabolism of ethanol in hypothyroid rats.