• Structural Engineering and Mechanics
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• 제50권1호
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• pp.1-17
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• 2014

In this paper, overstrength, ductility and response modification factors are calculated for frames braced with a different type of buckling restrained braces, called reduced yielding segment BRB (Buckling Restrained Brace) in which the length of its yielding part is reduced and placed in one end of the brace element in comparison with conventional BRBs. Forthermore, these factors are calculated for ordinary BRBF and the results are compared. In this regard incremental dynamic analysis (IDA) method is used for studying 17 records of the most known earthquakes happened in the world. To do that, the considered buildings have different stories and two bracing configurations: diagonal and inverted V chevron, the most ordinary configurations of BRBFs. Static pushover analysis, nonlinear incremental dynamic analysis and linear dynamic analysis have been performed using OpenSees software. Considering the results, it can be seen that, overstrength, ductility and response modification factors of this type of BRBF(Buckling Restrained Braced Frame) is greater than those of conventional types and it shows better seismic performance and also eliminates some of conventional BRBF's disadvantages such as low post-yield stiffness.

• 한국멀티미디어학회논문지
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• 제22권5호
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• pp.588-600
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• 2019

Each year Malaria affects over 200 million people worldwide. Particularly, African continent is highly hit by this disease. According to many researches, this continent is ideal for Anopheles mosquitoes which transmit Malaria parasites to thrive. Rainfall volume is one of the major factor favoring the development of these Anopheles in the tropical Sub-Sahara Africa (SSA). However, the surveillance, monitoring and reporting of this epidemic is still poor and bureaucratic only. In our paper, we proposed a method to fast monitor and report Malaria instances by using Social Network Systems (SNS) and precipitation volume in Nigeria. We used Twitter search Application Programming Interface (API) to live-stream Twitter messages mentioning Malaria, preprocessed those Tweets and classified them into Malaria cases in Nigeria by using Support Vector Machine (SVM) classification algorithm and compared those Malaria cases with average precipitation volume. The comparison yielded a correlation of 0.75 between Malaria cases recorded by using Twitter and average precipitations in Nigeria. To ensure the certainty of our classification algorithm, we used an oversampling technique and eliminated the imbalance in our training Tweets.

• Journal of Dental Anesthesia and Pain Medicine
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• 제22권2호
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• pp.129-143
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• 2022

Background: Patient-controlled analgesia (PCA) has been widely used as an effective medical treatment for pain and for postoperative analgesia. However, improper dose errors in intravenous (IV) administration of narcotic analgesics from a PCA infusion pump can cause patient harm. Furthermore, opioid overdose is considered one of the highest risk factors for patients receiving pain medications. Therefore, accurate delivery of opioid analgesics is a critical function of PCA infusion pumps. Methods: We designed a microbalance method that consisted of a closed acrylic chamber containing a layer and an oil layer with an electronic balance. A commercially available infusion analyzer (IDA-5, Fluke Co., Everett, WA, USA) was used to measure the accuracy of the infusion flow rate from a commercially available smart PCA infusion pump (PS-1000, UNIMEDICS, Co., Ltd., Seoul, Korea) and compared with the results of the microbalance method. We evaluated the uncertainty of the flow rate measurement using the ISO guide (GUM:1995 part3). The battery life, delay time of the occlusion alarm, and bolus function of the PCA pump were also tested. Results: The microbalance method was good in the short-term 2 h measurement, and IDA-5 was good in the long-term 24 h measurement. The two measurement systems can complement each other in the case of the measurement time. Regarding battery performance, PS-1000 lasted approximately 5 days in a 1 ml/hr flow rate condition without recharging the battery. The occlusion pressure alarm delays of PS-1000 satisfied the conventional alarm threshold of occlusion pressure (300-800 mmHg). Average accuracy bolus volume was measured as 63%, 95%, and 98.5% with 0.1 ml, 1 ml, and 2 ml bolus volume presets, respectively. A 1 ml/hr flow rate measurement was evaluated as 2.08% of expanded uncertainty, with a 95% confidence level. Conclusion: PS-1000 showed a flow accuracy to be within the infusion pump standard, which is ± 5% of flow accuracy. Occlusion alarm of PS-1000 was quickly transmitted, resulting in better safety for patients receiving IV infusion of opioids. PS-1000 is sufficient for a portable smart PCA infusion pump.

• 한국통신학회논문지
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• 제31권10C호
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• pp.942-947
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• 2006

In this paper, a new feature representation technique called Improved 2-directional 2-dimensional direct linear discriminant analysis (Improved $(2D)^2$ DLDA) is proposed. In the case of face recognition, thesmall sample size problem and need for many coefficients are often encountered. In order to solve these problems, the proposed method uses the direct LDA and 2-directional image scatter matrix. Moreover the selection method of feature vector and the method of similarity measure are proposed. The ORL face database is used to evaluate the performance of the proposed method. The experimental results show that the proposed method obtains better recognition rate and requires lesser memory than the direct LDA.

• 한국경영과학회지
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• 제10권1호
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• pp.14-30
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• 1985

Recently, multiple criteria decision making has been well established as a practical approach to seek a satisfactory solution to a decision making problem. Goal programming is one of the most powerful MCDM tools with satisfying operational assumptions that reflect the actual decision making process in real-world situations. In this paper we propose an efficient method implemented on a microcomputer for solving linear goal programming problems. It is an iterative revised goal simplex method using the sparsity technique. We design as interactive software package for microcomputers based on this method. From some computational experiences, we can state that the revised iterative goal simplex method using the sparsity technique is the most efficient one for microcomputer for solving goal programming problems.

• Steel and Composite Structures
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• 제13권6호
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• pp.561-570
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• 2012

Seismic collapse analysis requires efficient and automated method to perform thousands of time history analyses. The paper introduced the advantages of speed and convergence property of explicit method, provided a few techniques to accelerate speed of calculation and developed an automated procedure for collapse assessment, which combines the strong capacity of commercial explicit finite element software and the flexible, intelligent specialties of control program written in FORTRAN language aiming at collapse analysis, so that tedious and heavy work of collapse analysis based on FEMAP695 can be easily implemented and resource of calculation can be made the best use of. All the key commands of control program are provided to help analyzers and engineers to cope with collapse assessment conveniently.

• Clinical and Experimental Pediatrics
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• 제48권3호
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• pp.284-291
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• 2005

목 적 : 최근에 개발된 자동화혈구계산기를 이용하여 신속 간편하고 정확하게 IRF과 다양한 RCI 측정이 가능해졌다. 저자들은 정상 소아의 연령군별 RCI와 IRF의 정상치를 구하고, 소아빈혈 중 가장 흔한 원인질환인 철결핍성빈혈과 급성감염성빈혈을 포함한 소아빈혈군에서 RCI와 IRF치를 조사하여 소아빈혈의 조기진단과 철결핍성빈혈과 급성감염성빈혈의 감별진단에 유용한지를 알아보고자 하였다. 방 법 : 소아빈혈환자군 61명(급성감염성빈혈 34명, 철결핍성 빈혈 28명)과 정상대조군 57명을 대상으로 자동화혈구계산기 ADVIA 120을 이용하여 IRF과 CHr, MCVr, CHCMr, RDWr, HDWr 및 CHDWr를 포함한 RCI를 측정 후 대조군과 빈혈군 및 철결핍성빈혈군과 급성감염성빈혈군간의 평균치를 비교 분석하였다. 결 과 : 1) 정상대조군의 각 연령군별 IRF 평균치는 신생아군에서 가장 높았다. 정상대조군의 각 연령군별 RCI의 평균값을 비교해보면 신생아군에서 CHr, MCVr 및 HDWr이 다른 연령군에 비해 높았으나 CHCMr과 RDWr은 연령군별 차이를 보이지 않았다. 2) 빈혈군의 IRF는 정상대조군에 비하여 의미 있게 높았고, CHr과 CHCMr은 빈혈군에서 대조군에 비해 낮게 측정되었다. 그러나 MCVr은 빈혈군과 대조군 사이에 차이를 보이지 않았다. 3) 철결핍성빈혈군의 IRF는 정상대조군에 비하여 의미 있게 높았고, RCI 중 CHr과 CHCMr은 철결핍성빈혈군에서 대조군에 비하여 낮게 측정되었으며, RDWr은 철결핍성빈혈군에서 높았고, MCVr과 HDWr은 두 군간에 차이를 보이지 않았다. 4) 급성감염성빈혈군과 대조군의 IRF와 RCI를 비교해 보면 IRF는 급성감염성빈혈군에서 의미 있게 높았고, RCI 중 CHDWr만 차이를 보였으며, CHr, MCVr, CHCMr, RDWr 및 HDWr은 두 군간에 의의 있는 차이를 보이지 않았다. 5) 철결핍성빈혈군과 급성감염성빈혈군 간에 평균연령, 혈색소치 및 망상적혈구수는 차이가 없었다. IRF은 철결핍성빈혈군에 비하여 급성감염성빈혈군에서 의의 있게 높았고, RCI 중 CHr과 CHCMr은 급성감염성빈혈군에 비하여 철결핍성빈혈군에서 의의 있게 낮았으나, MCVr, RDWr 및 HDWr은 두 군간에 차이를 보이지 않았다. 결 론 : 빈혈의 감별진단에 IRF와 RCI가 매우 유용하리라 생각되며 특히 IRF는 급성감염에 의한 빈혈군에서 증가하는 것으로 보아 급성염증에 의한 골수반응이 있음을 생각할 수 있고, 또한 RCI 중 CHr은 빈혈의 감별진단에 아주 유용하고 특히 철결핍성빈혈군의 초기 진단에 유용하나 이에 대해 더욱 많은 연구가 필요하리라 사료된다.

• 한국미생물·생명공학회지
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• 제26권2호
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• pp.137-142
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• 1998

본 실험에서는 만성위염, 위궤양, 십이지장궤양, 위암발생의 원인균으로 알려진 H. pylori를 저해하는 특이항균물질을 생성하는 균주를 토양에서 분리한 방선균액과 곰팡이 추출액을 대상으로 탐색하여 곰팡이 균주번호 60686을 선별하였다. Jar fermentor로 배양하여 얻은 균체를 acetone 및 EtOAc로 추출하였고, 얻어진 추출액을 silica column chromatography와 LH-20 gel chromatography를 수행하여 활성분획을 농축하였고 HPLC를 사용하여 항균 활성을 나타내는 단일물질 IDA를 분리 정제하였다. 항균 활성물질 IDA의 구조를 MS, NMR 분석등을 통해 추정한 결과 곰팡이의 2차 대사산물인 cytochalasan의 전형적 구조를 갖는 분자식 $C_{32}H_{36}N_2O_5$의 chaetoglobosin A라는 물질로 판명되었다. 항균물질 IDA의 항균력을 paper disk법으로 실험한 결과 그람양성 균주중에서는 S. aureus SG 511, 285와 503 3주에서만 항균력을 보였고, 그람음성 균주중에서는 H. pylori 4주에서만 항균력을 보였으나 동일농도 처리시 H. pylori에 대한 항균력이 S. aureus에 비해 우수한 항균효과를 가진다고 판단되었다.

• Clinical and Experimental Pediatrics
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• 제53권1호
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• pp.89-92
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• 2010

장문합부위 궤양은 영유아기에 장 절단과 문합 후 발생하는 합병증으로 발병기전은 아직 정확하게 밝혀져 있지 않으며, 효과적인 치료법도 아직 개발되어 있지 않다. 저자들은 10세 된 여아의 만성 철 결핍 빈혈과 성장부전의 원인을 찾기 위하여 실시한 대장 내시경검사에서 장문합부위 궤양을 발견하고, 궤양이 있는 부위의 수술적 제거와 문합부 재교정 이후 증상의 호전을 경험하였기에 문헌고찰과 함께 국내 처음으로 보고하는 바이다. 장 절단술 후 증상의 발현이 늦어 진단이 어렵기 때문에 영유아기에 수술을 받은 환자의 경우 추적관찰을 통해 장문합부위 궤양의 발병 가능성을 예의주시해야 한다.

• Computers and Concrete
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• 제26권6호
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• pp.483-495
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• 2020

Dams are vital infrastructures that are expected to maintain their stability during seismic excitations. Accordingly, cemented material dams are an emerging type, which are being increasingly used around the world owing to benefiting from advantages of both earth-fill and concrete gravity dams, which should be designed safely when subjected to strong ground motion. In the present paper, the seismic performance of a cemented sand and gravel (CSG) dam is assessed using incremental dynamic analysis (IDA) method by accounting for two failure modes of tension cracking and base joint sliding considering the dam-reservoir-foundation interactions. To take the seismic uncertainties into account, the dam is analyzed under a suite of ground motion records and then, the effect of friction angle for base sliding as well as deformability of the foundation are investigated on the response of dam. To carry out the analyses, the Cindere dam in Turkey is selected as a case study, and various limit states corresponding to seismic performance levels of the dam are determined aiming to estimate the seismic fragilities. Based on the results, sliding of the Cindere dam could be serious under the maximum credible earthquake (MCE). Besides, dam faces are mostly to be cracked under such level of intensity. Moreover, the results indicate that as friction angle increases, probability of sliding between dam and foundation is reduced whereas, increases tensile cracking. Lastly, it is observed that foundation stiffening increases the probability of dam sliding but, reduces the tensile damage in the dam body.