• Journal of Information Science Theory and Practice
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• v.8 no.2
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• pp.55-67
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• 2020

Webometric research in the Russian library sector is just beginning to gain momentum. This article examines the experience of webometric research in libraries from the perspective of the global practice. In particular, it highlights a number of foreign works, which may have a special practical value for Russian libraries, and emphasizes important webometrics areas for libraries. The purpose of this study is to research the practical application of key performance indicators (KPIs) abroad and conduct a webometric analysis of the websites of some leading Siberian and Far Eastern scientific libraries based on selected KPIs. The study data were collected with SimilarWeb and other analytical tools. The study revealed that key traffic metrics are the basis of webometric research, and identified available promising groundwork for the purpose of their further testing. The shortcomings in the current state of the websites of the Siberian and Far Eastern scientific libraries were noted. Based on the obtained webometric traffic indicators, the ranking of the Siberian and Far Eastern scientific libraries was made.

• Journal of Theoretical and Applied Mechanics
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• v.2 no.1
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• pp.31-50
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• 1996

In this paper, a finite element analysis based on the local approach concept to fracture in the continuum damage mechanics is performed to analyze ductile fracture in two dimensional quasi-static state. First an isotropic damage model based on the generalized concept of effective stress is proposed for structural materials in the context of large deformation. In this model, the stiffness degradation is taken as a measure of damage and so, the fracture phenomenon can be explained as the critical deterioration of stiffness at a material point. The modified Riks' continuation technique is used to solve incremental iterative equations. Crack propagation is achieved by removing critically damaged elements. The mesh size sensitivity analysis and the simulation of the well known shearing mode failure in plane strain state are carried out to verify the present formulation. As numerical examples, an edge cracked plate and the specimen with a circular hole under plane stress are taken. Load-displacement curves and successively fractured shapes are shown. From the results, it can be concluded that the proposed model based on the local approach concept in the continuum damage mechanics may be stated as a reasonable tool to explain ductile fracture initiation and crack propagation.

• The Mathematical Education
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• v.45 no.2 s.113
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• pp.205-215
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• 2006

One of the most important concepts in the 7th curriculum of Korea is the student-centered education. Since educational evaluation has significant influence on the whole curriculum, if we realize the importance of the student-center education on the curriculum we should establish the student-centered educational evaluation system. Educational evaluation is defined by the theory of information to permit information users to identify, to measure, to manipulate and to communicate useful educational information concerning an educational curriculum for making decisions. If we accept the above definitions, the demands of information users are significant in the light of conceptual framework of educational evaluation. The purpose of this study is to analyze the conceptual framework of educational evaluation from information users' perspectives and to investigate the qualitative characteristics which satisfy information users' need for making decisions. We also show that students aren't provided sufficient evaluation results information to decide for their study plans by analyzing an evaluation study of the 7th primary curriculum. Finally, this study suggests how to improve an evaluation system for students in mathematics.

• Journal of the Institute of Convergence Signal Processing
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• v.11 no.2
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• pp.104-111
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• 2010

This paper presents an adaptive image enhancement method using the spatial frequency property in the DCT(discrete cosine transform) compressed domain. The dc coefficients, the illumination components of image, are adjusted to compress the dynamic range of image, and the ac coefficients are modified to enhance the contrast by using the human visual system(HVS) and the spatial frequency property. The ac coefficients are separated into vertical direction, horizontal direction, and mixed spatial frequency components, and adaptively modified to minimize the block artifacts that possibly occur in the image enhancement. The proposed method using dynamic range compression and adaptive contrast enhancement shows the advanced performance without the block artifact compared with existing method.

• Journal of KIISE:Computer Systems and Theory
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• v.33 no.8
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• pp.486-494
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• 2006

In this paper, we introduce a new solution for the load balancing problem, an important issue in parallel processing. Our heuristic load balancing technique called MGA effectively combines the benefit of both mean-field annealing (MFA) and genetic algorithms (GA). We compare the proposed MGA algorithm with other mapping algorithms (MFA, GA-l, and GA-2). A multiprocessor mapping algorithm simulation has been developed to measure performance improvement ratio of these algorithms. Our experimental results show that our new technique, the composition of heuristic mapping methods improves performance over the conventional ones, in terms of solution quality with a longer run time.

• Journal of Information Science Theory and Practice
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• v.2 no.3
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• pp.29-39
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• 2014

In recent years, several studies have proposed making use of the Twitter micro-blogging service to track various trends in online media and discussion. In this study, we specifically examine the use of Twitter to track discussions of food safety in the Korean language. Given the irregularity of keyword use in most tweets, we focus on optimistic machine-learning and feature set selection to classify collected tweets. We build the classifier model using Naive Bayes & Naive Bayes Multinomial, Support Vector Machine, and Decision Tree Algorithms, all of which show good performance. To select an optimum feature set, we construct a basic feature set as a standard for performance comparison, so that further test feature sets can be evaluated. Experiments show that precision and F-measure performance are best when using a Naive Bayes Multinomial classifier model with a test feature set defined by extracting Substantive, Predicate, Modifier, and Interjection parts of speech.

• Journal of Information Science Theory and Practice
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• v.1 no.2
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• pp.36-57
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• 2013

Blogs are readily available sources of opinions and sentiments which allows bloggers to exert a certain level of influence over the blog readers. Previous studies had attempted to analyze blog features to detect influence within the blogosphere, but had not studied in details influence at the blogger-level. Other studies studied bloggers' personalities with regards to their propensity to blog, but did not relate the personalities of bloggers to influence. Bloggers may differ in their way or manner of exerting influence. For example, bloggers could be active participants or just passive shares, or whether they express ideas in a rational or subjective manner, or they are received positively or negatively by the readers. In this paper, we further analyze the engagement style (frequency, scope, originality, and consistency of the blog postings), persuasion style (appeals to reasons or emotions), and persona (degree of compliance) of individual bloggers. Methods used include similarity analysis to detect the sharing-creating aspect of engagement style, subjectivity analysis to measure persuasion style, and sentiment analysis to identify persona style. While previous studies analyzed influence at blog site level, our model is shown to provide a fine-grained influence analysis that could further differentiate the bloggers' influence style in a blog site.

• Journal of the Korea Safety Management & Science
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• v.14 no.2
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• pp.147-158
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• 2012

This paper aims to develop a new chain metrics for obtaining lean Overall Equipment Effectiveness(OEE) and present implementation strategy which considers the properties for Total Productive Maintenance(TPM) to reduce machine losses, Performance Analysis and Control(PAC) to reduce labor losses, Lean Production System(LPS) to reduce floor wastes, and Theory of Constraints(TOC) to minimize the problem of Capacity Constrained Resource(CCR). The study reviews the related literatures and reformulates the structure of machine losses, labor losses and field wastes. The research also develops the integrated productivity metrics according to time, units, reliability and maintainability. It is found that the study develops the actual productivity measure in terms of efficiency, effectiveness and standard productivity. In addition to that, it outlines and develops by using the integrated LPS and TPM, lean OEE measures such as Time Based Productivity(TBP), Unit Based Productivity(UBP), and Reliability & Maintainability Based Availability(RMBA). Implication examples are proposed to make it easier and available for practioners to understand the implementation strategies about TPM OEE, lean OEE and TOC OEE. Futhermore related to other studies, the research contributes to create a new chain productivity measures to clear the interrelationship concepts of productivity, efficiency and effectiveness. Moreover the paper develops the enhanced OEE measures by integration of TPM, PAC, LPS and TOC with the perspective of schedule, throughput, reliability, maintainability and availability.

• The Journal of the Acoustical Society of Korea
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• v.6 no.4
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• pp.5-11
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• 1987

In this paper, the measurement of SAW velocity on piezoelectric ceramic is studied. It can be done by using oscilloscope and pulse generator, and measure the velocity especially when feed-through is appeared. The propagating distance was exactly calculated considering that IDT responses are obtained by convolution theory, therefore the velocity was measured by the above simple method. As the results, the measurement velocity at room temperature was 3480 m/sec for $YZ-LiNbO_3$ single crystal and 2770 m/sec for a family of $PbTiO_3$ceramics with feed-through signal.

• Journal of Korean Elementary Science Education
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• v.24 no.5
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• pp.518-530
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• 2005

The purpose of this study was to investigate the characteristics of pre-service primary teachers' justifying their hypotheses about the brightness of electric bulbs. They conducted their experiments and wrote their experimental results and ideas on their worksheets. The worksheets for generating and evaluating scientific hypothesis were analyzed. Most of them generated the consumption hypothesis and designed the experiments to confirm their hypotheses or directly measure without the change of experimental conditions. The responses for valid experimental designs were $74\%$ of total responses. The $62\%$ of total responses was valid prediction for experimental results. The $60\%$ of pre-service teachers described the experimental results correctly. But other teachers described the biased results or inappropriate results. The $54\%$ of them refuted hypotheses and the $36\%$ confirmed their hypotheses. The theory-based responses were $51\%$ and the evidence-based responses were $47\%$. The $64\%$ of them proposed the possibility of the alternative hypothesis after testing their hypotheses. This study also discussed the implications of these findings for teaching and Loaming in science education.