• Natural Product Sciences
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• 제19권4호
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• pp.355-359
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• 2013

A new monoterpene, crocusatin M (1), was isolated from the flower buds of Buddleja officinalis, together with four known monoterpenes, (6R)-hydroxy-1,1,5-trimethylcyclohex-4-enone (2), (+)-dehydrovomifoliol (3), 7-epiloliolide (4), and crocusatin D (5). Their structures were determined by an extensive analysis of 1D, 2D NMR, HRESI-MS, and CD data as well as by comparison of their spectroscopic data with those of literatures. All isolates were evaluated for inhibitory activities on LPS-induced nitric oxide production in RAW 264.7 cells. Among them, compounds 2 and 3 showed moderate inhibitory effects with $IC_{50}$ values of 63.8 and 24.4 ${\mu}g/ml$, respectively.

• 한국경영과학회지
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• 제29권1호
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• pp.43-56
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• 2004

The purpose of clustering is to partition a set of objects into several clusters based on some appropriate similarity measure. In most cases, clustering is considered without any prior information on the number of clusters or the structure of the given data, which makes clustering is one example of very complicated combinatorial optimization problems. In this paper we propose a general-purpose clustering method that can determine the proper number of clusters as well as efficiently carry out clustering analysis for various types of data. The method is composed of two stages. In the first stage, two different hierarchical clustering methods are used to get a reasonably good clustering result, which is improved In the second stage by ASA(accelerated simulated annealing) algorithm equipped with specially designed perturbation schemes. Extensive experimental results are given to demonstrate the apparent usefulness of our ASA clustering method.

• 공학교육연구
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• 제15권6호
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• pp.19-33
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• 2012

We analyze the problems of curriculum management and accreditation criteria through data analysis and survey on domestic and foreign curriculums and accreditation criteria, propose an efficient curriculum model based on educational realities and requirements of all university members and suggest improvement direction for more efficient curriculum management and accreditation criteria. For this study, we investigate curriculum data of several domestic and foreign universities, analyze the datum in various aspects and conduct a survey on curriculum management and accreditation criteria for collecting extensive opinion of university members on curriculum management and accreditation criteria. We expect that the proposed curriculum model and improvement direction of curriculum and accreditation criteria will help university members to efficiently manage accreditation programs.

• Journal of Electrical Engineering and information Science
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• 제2권4호
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• pp.37-45
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• 1997

With rapid increase of information requirements from various application areas, there has been much research on dynamic information storage structures that effectively support insertions, deletions and updates. In this appear we evaluate the performance of he existing dynamic signature file methods such as the S-tree, Quick Filter and HS file and provide guidelines for the most effective usage to a given operational environment. We derive analytic performance evaluation models of the storage structures based on retrieval time, storage overhead and insertion time. We also perform extensive experiments with various data distributions such as uniform, normal and exponential distributions. The relationships among various performance parameters are throughly investigated. We show through performance comparison based on analytic models and experiments that regardless of data distribution, the HS file significantly improves performance in both the retreival time and the storage overhead over S-tree and Quick Filter.

• Nuclear Engineering and Technology
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• 제30권5호
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• pp.444-451
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• 1998

The cost-effective reduction of occupational radiation exposure (ORE) dose at a nuclear power plant could not be achieved without going through an extensive analysis of accumulated ORE dose data of existing plants. It is necessary to identify what are high ORE jobs for ALARA implementation. In this study, the Rank Sum Method (RSM) is used in identifying high ORE jobs. As a case study, the database of ORE-related maintenance and repair jobs for Kori Units 3 and 4 is used for assessment, and top twenty high ORE jobs are identified. The results are also verified and validated using the Friedman test, and RSM is found to be a very efficient way of analyzing the data.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1994년도 교수 연수회(역학)
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• pp.142-149
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• 1994

Substitution of graphic representation for extensive lists of numerical statistical data is highly desirable by both editors and readers of medical journals, faced with an exploding abundance of contemporary medical literature. A novel graphic tool. the 'double-ring diagram', is described herein which permits visual representation of information regarding certain statistical variables used to describe the performance of a test or physical sign in the diagnosis of a disease. The diagram is relatively easy to construct on the basis of a number of primary data such as the prevalence and the true positive, true negative. false positive and false negative test results. These values are reflected in the diagram along with the values of other statistical variables derived from them. such as the sensitivity. specificity, predictive values for positive and negative test result. and accuracy. This diagram may be useful in visualizing a test's performance and facilitating visual comparison of performance of two or more tests.

• 가정과삶의질연구
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• 제23권3호
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• pp.63-76
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• 2005

Using the data from the Family Income & Expenditure Survey, this study investigated (1)the factors determining the level of burden of the private educational expenditure in households; (2) the influences of the level of the burden of private educational expenditure on the other household expenditures. For the analysis of data Chi-square, GLM, Multinomial legit, and Seemingly Unrelated Regression were applied. The major findings were: (1) The factors associated with the burden of private educational expenditure were the number of students by each of the school levels, housing tenure, location of residence, educational attainment of householder; (2) Households with the lower level of burden of the private educational expenditure adjusted the allocation of the expenditure shares of food, utility, and transportation and did not reduce the levels of consumption. Households with the higher level of burden of the private educational expenditure adjusted the extensive ranges of the household expenditure shares and reduced the levels of consumption.

• Asia pacific journal of information systems
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• 제11권4호
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• pp.113-133
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• 2001

We propose utilizing a fuzzy cognitive map(FCM) to integrate tacit knowledge and explicit knowledge both of which are crucial to the success of knowledge management. Recently, explicit knowledge is getting more available as CRM and data mining approaches become popular as the advent of using database and the Internet technology. However, for the knowledge management to be successful, tacit knowledge should be seamlessly integrated with explicit knowledge seamlessly. The problem hindering such effort is how to find a vehicle facilitating transformation of explicit knowledge into tacit knowledge, and vice versa. FCM has been important method for representing tacit knowledge as a form of explict knowledge. In this respect, we suggest the detailed process about how to integrate explicit knowledge and tacit knowledge by using FCM. We gathered extensive set of data from the credit card company, and applied our proposed method. Results showed that our approach is robust and promising for the field of integrating two different kinds of knowledge.

• 대한원격탐사학회지
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• 제26권6호
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• pp.731-740
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• 2010

A region merging technique is suggested in this paper for the segmentation of high-spatial resolution imagery. It employs a region growing scheme based on the region adjacency graph (RAG). The proposed algorithm uses directional neighbor-line average feature vectors to improve the quality of segmentation. The feature vector consists of 9 components which includes an observation and 8 directional averages. Each directional average is the average of the pixel values along the neighbor line for a given neighbor line length at each direction. The merging coefficients of the segmentation process use a part of the feature components according to a given merging coefficient order. This study performed the extensive experiments using simulation data and a real high-spatial resolution data of IKONOS. The experimental results show that the new approach proposed in this study is quite effective to provide segments of high quality for the object-based analysis of high-spatial resolution images.

• Archives of Pharmacal Research
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• 제27권7호
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• pp.734-737
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• 2004

5,8-Epidioxycholest-6-en-3-ol (1), cholesterol (2), glycerol 1-palmitate (3) and glycerol 1,3-dioleate-2-stearate (4) were isolated from the methanol extract of the sea urchin Diadema setosum, which was collected from the Halong sea, Vietnam. Chemical structures were established based on extensive 1D, 2D-NMR, FAB-MS, EI-MS spectroscopic data and GC-MS analysis. The NMR spectral data of compound 1 were reassigned by using HMQC and HMBC. Compound 1 was found to have strong cytotoxic effect against various cancer cell lines, such as KB ($IC_{50}$, 2.0 $\mu\textrm{g}$/mL), FL($IC_{50}$, 3.93 $\mu\textrm{g}$/mL), and Hep-2 ($IC_{50}$, 2.4 $\mu\textrm{g}$/mL) by in vitro assay.