• Journal of The Korean Astronomical Society
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• v.46 no.1
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• pp.41-47
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• 2013

I present a simple scheme for the treatment of gravitational interactions on galactic scales. In anal- ogy with known mechanisms of quantum field theory, I assume ad hoc that gravitation is mediated by virtual exchange particles-gravitons-with very small but non-zero masses. The resulting den- sity and mass profiles are proportional to the mass of the gravitating body. The mass profile scales with the centripetal acceleration experienced by a test particle orbiting the central mass, but this comes at the cost of postulating a universal characteristic acceleration $a_0{\approx}4.3{\times}10^{-12}msec^{-2}$ (or $8{\pi}a_0{\approx}1.1{\times}10^{-10}msec^{-2}$). The scheme predicts the asymptotic flattening of galactic rotation curves, the Tully-Fisher/Faber-Jackson relations, the mass discrepancy-acceleration relation of galaxies, the surface brightness-acceleration relation of galaxies, the kinematics of galaxy clusters, and "Renzo's rule" correctly; additional (dark) mass components are not required. Given that it is based on various ad-hoc assumptions and given further limitations, the scheme I present is not yet a consistent theory of gravitation; rather, it is a "toy model" providing a convenient scaling law that simplifies the description of gravity on galactic scales.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.1
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• pp.25-31
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• 2014

Korean grammar checkers typically detect context-dependent errors by employing heuristic rules; these rules are formulated by language experts and consisted of lexical items. Such grammar checkers, unfortunately, show low recall which is detection ratio of errors in the document. In order to resolve this shortcoming, a new error-decision rule-generalization method that utilizes the existing KorLex thesaurus, the Korean version of Princeton WordNet, is proposed. The method extracts noun classes from KorLex and generalizes error-decision rules from them using the Tree Cut Model and information-theory-based MDL (minimum description length).

• English Language & Literature Teaching
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• v.9 no.2
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• pp.109-132
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• 2003

The purpose of the present study is to explore effective ways of teaching English grammar, which is geared toward improving students' communicative competence. Grammatical competence is essential to communicative competence. Grammatical knowledge cannot be acquired unconsciously in an EFL environment such as in Korea. Therefore learners should be given grammar instruction. More importantly, they should be instructed in grammar so that they can develop their grammatical abilities which are the foundation of communicative competence. The following is proposed for the grammar instruction placing the focus on improving communicative competence. First, it is effective to explain the form, meaning and pragmatics of a grammatical rule to learners in Korean. Second, learners should be given instruction in grammatical patterns that deals with constructions and meanings together, which can enable them to produce sentences by themselves. Third, it should be taught to understand constructions and meanings on the basis of word orders. Then the following steps of grammar instruction are suggested. In the first step of grammatical instruction, students should be provided with the illustrations of grammatical structures which link communicative functions and grammar. In the second step, learners should be gotten to practice grammatical constructions repeatedly enough to use them unconsciously. Lastly, communicative activities such as description and role plays should be included in grammar instruction to integrate grammar practice and communicative language use.

• Journal of Korean Library and Information Science Society
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• v.38 no.1
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• pp.341-361
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• 2007

This research aims at the thorough analysis between the first edition and the revised of the International Standard Archival Authority Record for Corporate Bodies, Personal and Families. The focused methods of the study are comparing with each strength and weakness of the first edition and the revised on the needs and the features of archival authority control as well as how to use its description rule. Besides it looks into the elements to be added and complemented as they are made practical use of archives, hereafter when it is established Korean archival authority control rules, this fundamental research can be certainly valuable as its basic materials.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2005.11a
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• pp.276-279
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• 2005

A review of how the functions of two or more independent variables can be approximated by using fuzzy systems is provided in this paper. We start with an exact represention of a linear interpolation function of two independent variables by using a fuzzy system. Next, we describe how this function can be approximated by another fuzzy system with a lesser number or with a desired number of output fuzzy sets. Thus, a reduction of the storage needed is achieved by storing the fuzzy rules or equivalently the output fuzzy set numbers instead of storing the whole discrete function values. A description on how the cubic spl me interpolation function can be represented exactly by using the fuzzy system method is provided, along with a few examples where fuzzy rule tables with a size of 7$\times$7 provide a representation of the functions with relative errors of the order of $10^{2}$ or less.

• Parasites, Hosts and Diseases
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• v.52 no.5
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• pp.545-549
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• 2014

Sparganosis is an infection with a parasitic tapeworm larva that occurs by eating infected foods or drinking contaminated water. The larvae can migrate to a tissue or muscle in the chest, abdominal wall, extremities, eyes, brain, urinary tract, pleura, pericardium, spinal canal, or scrotum. Herein, we report a 5-month old infant with scrotal sparganosis who was initially suspected to have a scrotal inflammatory mass with a history of applying raw frog meat into the umbilicus. Preoperative ultrasound examinations and computed tomography (CT) scanning misdiagnosed the mass as a scrotal teratoma. The scrotal mass was surgically removed, and the histopathology proved it to be scrotal sparganosis. This case displays the youngest patient ever reported with scrotal sparganosis, and the first description of CT characteristics of scrotal sparganosis. A detailed medical history is necessary for patients with scrotal masses suspected of sparganosis. In addition, ultrasound and CT examinations are helpful to rule out other causes of a scrotal mass.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.1
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• pp.93-101
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• 2010

Currently lots of studies to solve meta-data interoperability in between schema attributes are conducted. But the accuracy in previous schema mapping studies is low since the studies just use the similarity in between attributes. So the studies are not suitable for the schema mapping such as document conversion, system integration, etc. In this paper, we propose a method which can conduct the schema mapping interactively using frequent pattern mining. The method can conduct more accurate mapping process because the method use the description element which is an element among each schema element for the metadata standard. A performance study has been conducted to compare the accuracy performance of the method using metadata standards.

• Journal of Environmental Impact Assessment
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• v.19 no.6
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• pp.573-581
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• 2010

Natural ecosystem is an essential part to connect with the plan for biodiversity conservation in response strategy against climate change. For connecting biodiversity conservation with climate change strategy, Europe, America, Japan, and China are making an effort to discuss protection necessity through national biodiversity valuation but precedent studies lack in Korea. In this study, we made biodiversity maps representing biodiversity distribution range using species richness in National Forest Inventory (NFI) and Forest Description data. Using regression tree algorithm, we divided various classes by decision rule and constructed biodiversity maps, which has accuracy level of over 70%. Therefore, the biodiversity maps produced in this study can be used as base information for decision makers and plan for conservation of biodiversity & continuous management. Furthermore, this study can suggest a strategy for increasing efficiency of forest information in national level.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.177-182
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• 2003

This study is directed toward determining the number and characteristics of psychologically meaningful perceptual dimensions required for assessing the sound Ouaiity with respect to vehicle interior and/or exterior noises. and toward identifying the acoustical or psychoacoustical bases underlying the perception. By nonmetric MDS and clustring analysis of sound quality data sets on our own, of critical importance are two perceptual dimensions for which subjective verdicts can be interpreted as loudness and sharpness. The perceptual dimensions based upon similarity judgments could be accounted for 48% and 24% of the variance. each of which might be a match for the acoustic parameter "A-weighted maximum pressure level"(r= .85) and for the psychoacoustic parameter "sharpness" (r= .65), respectively. On the other hand, the perceptual dimensions based upon preference ratings could explain 66% and 10% of the variance. where the acoustic parameter "A-weighted maximum pressure leve"(r= .92) might be taken to be a best predictor, but sharpness appeared to be less suitable for the description of Preference behavior. Linked to the results, the problems of quantitative modelling of subjective sound quality evaluation and also of implementing corresponding cognitive combination rule for technical and industrial applications, say having "winner-sound qualify" according to preference criteria will be shortly in discussion.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.5 no.3
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• pp.200-205
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• 2005

The objectives of this study were to introduce the easiest and most proper applications of datamining in industrial processes. Applying datamining in manufacturing is very different from applying it in marketing. Misapplication of datamining in manufacturing system results in significant problems. Therefore, it is very important to determine the best procedure and technique in advance. In previous studies, related literature has been introduced, but there has not been much description of datamining applications. Research has not often referred to descriptions of particular examples dealing with application problems in manufacturing. In this study, a datamining roadmap was proposed to support datamining applications for industrial processes. The roadmap was classified into three stages, and each stage was categorized into reasonable classes according to the datamining purposed. Each category includes representative techniques for datamining that have been broadly applied over decades. Those techniques differ according to developers and application purposes; however, in this paper, exemplary methods are described. Based on the datamining roadmap, nonexperts can determine procedures and techniques for datamining in their applications.