• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2004년도 춘계학술대회
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• pp.253-257
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• 2004

Platelet aggregation is a complex phenomenon that probably involves several intracellular biochemical pathways. When activated, platelets change shape, aggregate and release the contents of their intracellular granules. The interactions between platelets and blood vessel walls are important in the development of thrombosis and cardiovascular diseases. When blood vessels are damaged, platelet aggregation occurs rapidly to form haemostatic Plugs or arterial thrombi at the sites of vessel injury or in regions where blood flow is disturbed. These thrombi are the source of thromboembolic complications of atherosclerosis, heart attacks, stroke, and peripheral vascular disease. Therefore, the inhibition of platelet function represents a promising approach for the prevention of thrombosis. Plants constitute a rich source of bioactive chemicals such as phenolics, terpenoids and alkaloids. Plant extracts may be an alternative to currently used medicinal source because they constitute a rich source of bioactive chemicals. This study was performed to investigate the antiplatelet activity of extract of Tabebuia impetiginosa Martius ex DC (Taheebo) and find out which fractions to this activity in rabbit platelet. Taheebo was methanol extracted and solvent fractionated in to five fractions (hexane, chloroform, ethylacetate, butanol and water). And each fractions were investigated inhibitory effects on platelet aggregation induced by various agonists using washed rabbit platelets in vitro.

• Journal of the Korean Statistical Society
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• 제22권2호
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• pp.271-282
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• 1993

Unit root test for temporally aggregated first order autoregressive process is considered. The temporal aggregate of fist order autoregression is an autoregressive moving average of order (1,1) with moving average parameter being function of the autoregressive parameter. One-step Gauss-Newton estimators are proposed and are shown to have the same limiting distribution as the ordinary least squares estimator for unit root when complete observations are available. A Monte-Carlo simulation shows that the temporal aggregation have no effect on the size. The power of the suggested test are nearly the same as the powers of the test based on complete observations.

• 컴퓨터교육학회논문지
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• 제6권3호
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• pp.75-85
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• 2003

본 연구는 SCORM 기반 학습 객체의 메타데이타 생성 즉 Asset, SCO, Contents Aggregation과 Contents Package에 대한 메타데이터를 생성하는 시스템(MetaGene)을 개발한다. SCORM 을 지원하는 LMS내 API 어댑터와 인터페이스를 위한 학습 객체 내에 API 활성화 함수를 내장시키고, 데이터 모델을 기반으로 학습 과정을 트래킹 하는 코드도 포함 시킨다. 또한 학습 객체들이 LMS에 전송되게 PIF(Package Interchange File)로 패키징 시킨다. MetaGene에 생성된 학습객체의 메타데이터와 컨텐츠 패키지의 manifest file을 $SCORM^{(TM)}$ Conformance Testsuite을 이용하여 유효성을 검증한다.

• 기술혁신학회지
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• 제2권2호
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• pp.201-218
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• 1999

The article contains an introduction of possibility of applying Multi-Attribute Utility Theory(MAUT) for priority setting of R&D projects. MAUT is compared with AHP, which is widely used recently. These two techuiques are applied to set priorities of R&D projects In a Government-funded Research Institute. Six criteria are chosen from consultation with decision makers. They are composed of 1) validity as representative projects, 2) possibility of resource mobilization, 3) spillover effect of developed technologies, 4) possibility of success, 5) scope of participation and 6) clarity of research goal. To set priorities of R&D projects, SMART(Simple MultiAttribute Rating Technique) and DVM(Difference Value Measurement) out of many MAUT methods are used to design the utility function and to determine the weights among criteria. The aggregation model is additive on the assumption the criteria are independent. AHP executes pairwise comparisons for criteria and alternatives. From the results of the case study, the results and theoretical characteristics are compared.

• Journal of Electrochemical Science and Technology
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• 제5권2호
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• pp.53-57
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• 2014

With the use of diffusion-limited aggregation modeling, we have investigated the effect of particle drift for dendritic growth. It is found that the morphology of dendritic growth is sensitive to the particle drift, i.e., the larger drift effect results in the denser growth of dendrite. From the analysis using the correlation function, we found the fractional dimension of each dendrite increases as the particles drift increases. Furthermore, we showed the height of dendrite significantly decrease for the slight change of particles drift. Finally, we discussed the strategy to reduce dendritic growth by modifying the transport properties of electrolytes.

• Asian Journal of Atmospheric Environment
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• 제9권2호
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• pp.101-113
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• 2015

Air quality index (AQI) or air pollution index (API) is commonly used to report the level of severity of air pollution to public. A number of methods were developed in the past by various researchers/environmental agencies for determination of AQI or API but there is no universally accepted method exists, which is appropriate for all situations. Different method uses different aggregation function in calculating AQI or API and also considers different types and numbers of pollutants. The intended uses of AQI or API are to identify the poor air quality zones and public reporting for severity of exposure of poor air quality. Most of the AQI or API indices can be broadly classify as single pollutant index or multi-pollutant index with different aggregation method. Every indexing method has its own characteristic strengths and weaknesses that affect its suitability for particular applications. This paper attempt to present a review of all the major air quality indices developed worldwide.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2015년도 춘계학술발표대회
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• pp.132-135
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• 2015

맵리듀스(MapReduce)는 분산 환경에서의 빅데이터(Big Data), 즉 대용량 데이터를 처리하는 프로그래밍 모델이다. 대용량의 데이터를 분석하기 위해서 집계 함수(Aggregation function)로 데이터를 처리할 수 있다. 본 논문에서는 맵리듀스 환경을 기반으로 SQL 쿼리에서 집계 함수를 더 적은 비용으로 수행하며 효율적으로 처리할 수 있는 두 가지 전략을 제안한다. 두 가지 전략 중 더 높은 성능을 보이는 전략을 더 효율적인 처리 방법으로 판단한다. 첫 번째 전략은 두 테이블을 Join하여 집계 함수를 처리하는 방법이다. 두 번째 전략은 집계 함수를 처리하여 Join에 참여할 튜플의 수를 최소로 줄인 후 Join을 수행하고 다시 집계 함수를 처리하는 방법이다. 두 제안 방법을 비교하기 위하여 실험을 한 결과 두 번째 전략이 더 적은 비용이 드므로 더 효율적인 처리 방법인 것으로 보인다.

• 한국컴퓨터정보학회논문지
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• 제14권1호
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• pp.217-228
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• 2009

데이터에 내재되어 있는 특이 패턴을 찾고자 데이터 분석을 할 때에 보통 다차원적인 데이터 집계를 하는데, 이때에 표준 SQL 쿼리를 사용해도 좋지만 쿼리가 아주 복잡해진다는 단점이 생기게 된다. 쿼리가 복잡해지면 표준 테이블을 여러 번 참조해야 되고 결과적으로 쿼리의 성능이 저하된다는 뜻이다. OLAP 쿼리는 복잡한 것이 대다수이기 때문에 SQL 쿼리를 대신할 새로운 집계용 연산자인 데이터 큐브를 간단히 불러 큐브를 만들 필요가 생기는 것이다. 집계를 하고, 부분 합을 구하는 것과 같은 OLAP 업무를 지원해 주는 것이 데이터 큐브이다. 이러한 데이터 큐브를 작성하는데 관련된 집계함수에는 여러 가지가 있는데, 이를 분배적 함수, 대수적 함수 그리고 전체관적 함수의 3가지로 분류할 수 있다. 이 중, SUM, COUNT, MAX, MIN과 같은 분배적 함수는 데이터 큐브를 작성하는 데에 직접사용 할 수 있고, AVG와 같은 대수적 함수는 매개함수를 활용하면 사용가능 하다고 알려져 있다. 즉, AVG 자체는 분배적 함수가 아니지만, (SUM, COUNT)와 같은 매개함수로 분배적 함수가되기 때문에 매개함수를 이용하여 구하면 된다는 뜻이다. 그러나 본 연구에서는 (SUM, COUNT)와 같은 매개함수를 통해 AVG를 구하는 것이 OLAP 큐브 작성에 적용시킬 수 없다는 사실을 확인했으며, 결과적으로 이 매개함수를 활용하면 잘못된 결론에 다다르고 그릇된 의사결정을 하게 된다는 사실을 확인하게 되었다. 따라서 본 연구에서는 집계함수 AVG를 OLAP 큐브에 적용시켰을 때의 여러 문제점을 밝혀내고 또한 이들 문제점을 해결할 방안을 찾고자 하는 데에 목적을 두고 있다.

• 호남수학학술지
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• 제30권1호
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• pp.171-183
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• 2008

In a previous work [18], the authors investigated autocontinuity, converse-autocontinuity, uniformly autocontinuity, uniformly converse-autocontinuity, and fuzzy multiplicativity of monotone set function defined by Choquet integral([3,4,13,14,15]) instead of fuzzy integral([16,17]). We consider nonnegative monotone interval-valued set functions and nonnegative measurable interval-valued functions. Then the interval-valued Choquet integral determines a new nonnegative monotone interval-valued set function which is a generalized concept of monotone set function defined by Choquet integral in [18]. These integrals, which can be regarded as interval-valued aggregation operators, have been used in [10,11,12,19,20]. In this paper, we investigate some characterizations of monotone interval-valued set functions defined by the interval-valued Choquet integral such as autocontinuity, converse-autocontinuity, uniform autocontinuity, uniform converse-autocontinuity, and fuzzy multiplicativity.

• 대한한방내과학회지
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• 제22권4호
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• pp.547-555
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• 2001

Objectives: Obesity is regarded as the aggregation of needless risk factors, for instance, cardiovascular disease, joint disease, induce cancer. We studied on interrelation between abnormal liver function and obesity. Methods: We analyzed liver function, T.Cholesterol, Triglyceride before and after lose weight treatment. The collateral condition is over 6 weeks period on obesity treatment, no liver injury and no complicated another disease on personal past history and found out abnormal impression on biochemical liver function blood test. Results: The improvement rate of LFT, compare with before treatment is 10.6% in T.Bilirubin, 11.1% in ALP, 21% in AST, 38% in ALT, 37.3% in r-GTP, 9.2% in LDH and decreased 2.7% in T.Protein, increased 2.3% in Albumin. Hyperlipidemia is 19.4% in T.Cholesterol, 42.5% in Triglyceride. Conclusions: LFT and Hyperlipidemia of abnormal liver function patients, caused by obesity, is improved to normal limit in proportion to reduce patient's weight.