• English Language & Literature Teaching
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• v.9 no.2
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• pp.193-211
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• 2003

This study aims to illustrate students' and teachers' perceptions towards certification of English proficiency and proficiency- based curriculum, and to investigate their needs for developing college English program. A total of 597 students and 28 teachers participated in the survey. The findings showed that both groups acknowledged the usefulness of the certification of English proficiency and proficiency-based curriculum. However, both groups showed a negative response to 'waive test' (testing for the replacement of English required class). They also expressed high level of needs in increasing the number of courses and credit hours, reducing the class size, and improving facilities. Both groups perceived speaking and listening as more important skills, while students showed various preferences for effective language practice activities. The findings of this study suggest t hat the introduction of certification of English proficiency should he supplemented with follow-ups both in pedagogical aspect and on administrative level.

• Transactions on Control, Automation and Systems Engineering
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• v.2 no.1
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• pp.62-68
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• 2000

Fixtures are used in almost all phases of machining and assembly to position and hold a part accurately. The class of fixture which consists of 3 locators and 1 clamp(3L/1C) is known as the minimal set that can provide form closure which is a kinematic constraint condition for preventing all planar motions. This type of fixtures has advantages in terms of the number of fixture elements required, the time for clamping, and so on. However it is not widely used in industry because reliable loading scheme has not been reported. In this paper, we propose a method to load the class of 3L/1C fixtures using compliant motions. The planner is developed for synthesizing compliant motions to achieve precise final fixture configuration in the presence of sensing and control uncertainties. A novel approach to eliminate uncertainty in part orientation by adding one extra fixture element called an aligning pin is proposed.

• Proceedings of the IEEK Conference
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• 2004.06a
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• pp.179-182
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• 2004

The process of categorizing packets into 'class' in an Internet router is called packet classification. All packets with same class obey predefined rule specified in routing tables. Performing classification in real time on an arbitrary number of fields is a very challenge task. In this paper, we present a new algorithm named EnBiT-PC (EnBiT Packet Classification). and evaluate its performance against real classifiers in use today. We compare with previous algorithms, and found out that EnBiT-PC classify packets very efficiently and has relatively small storage requirements.

• The korean journal of orthodontics
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• v.10 no.1
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• pp.55-64
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• 1980

The purpose of this study was to investigate the interrelationship of the experimental group and control group by analyzing case histories, intraoral radiographs, orthopantomographs, intraoral slide films and dental casts. The data for this study were complied from 654 outpatients of the Department of Orthodontics, Seoul National University Hospital. The following conclusions were obtained. 1. When one or more thins molar teeth were congenitally missing, the incidence of the other congenitally missing teeth was high. 2. The frequency of congenitally missing teeth was comparatively higher in male, maxilla, class II and class III. 3. The congenitally missing srea of the third molar by Angle's classification was not significant. 4. The order of frequency of congenitally missing teeth was the third molar, the second premolar, the lateral incisor, the first premolar, the central incisor, the canine, the first molar, the second molar.

• Genomics & Informatics
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• v.8 no.4
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• pp.170-176
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• 2010

The Ribonucleotide reductases (RNR) are essential enzymes that catalyze the conversion of nucleotides to deoxynucleotides in DNA replication and repair in all living organisms. The RNRs operate by a free radical mechanism but differ in the composition of subunit, cofactor required and regulation by allostery. Based on these differences the RNRs are classified into three classesclass I, class II and class III which depend on oxygen, adenosylcobalamin and S-adenosylmethionine with an iron sulfur cluster respectively for radical generation. In this article thirty seven sequences belonging to each of the three classes of RNR were analyzed by using various tools of bioinformatics. Phylogenetic analysis, dot-plot comparisons and motif analysis was done to identify a number of differences in the three classes of RNRs. In this research article, we have attempted to decipher evolutionary relationship between the three classes of RNR by using bioinformatics approach.

• Communications for Statistical Applications and Methods
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• v.27 no.1
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• pp.129-140
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• 2020

In this paper, we introduce an efficient algorithm for the non-convex penalized multinomial logistic regression that can be uniformly applied to a class of non-convex penalties. The class includes most non-convex penalties such as the smoothly clipped absolute deviation, minimax concave and bridge penalties. The algorithm is developed based on the concave-convex procedure and modified local quadratic approximation algorithm. However, usual quadratic approximation may slow down computational speed since the dimension of the Hessian matrix depends on the number of categories of the output variable. For this issue, we use a uniform bound of the Hessian matrix in the quadratic approximation. The algorithm is available from the R package ncpen developed by the authors. Numerical studies via simulations and real data sets are provided for illustration.

• Journal of Korean Institute of Industrial Engineers
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• v.23 no.3
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• pp.451-467
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• 1997

Tabu search (TS) is a useful strategy that has been successfully applied to a number of complex combinatorial optimization problems. By guiding the search using flexible memory processes and accepting disimproved solutions at some iterations, TS helps alleviate the risk of being trapped at a local optimum. In this article, we propose TS-based heuristics for solving a class of clustering problems, and compare the relative performances of the TS-based heuristic and the simulated annealing (SA) algorithm. Computational experiments show that the TS-based heuristic with a long-term memory offers a higher possibility of finding a better solution, while the TS-based heuristic without a long-term memory performs better than the others in terms of the combined measure of solution quality and computing effort required.

• Journal of Korean Library and Information Science Society
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• v.25
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• pp.377-404
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• 1996

The purpose of this study is to investigate material designation in library cataloging and to suggest General Material Designation (GMD) and Specific Material Designation(SMD) in Korean. A summary of the study follows. In library cataloging, methods of indicating the type of material are : (1) color-coding, (2) media code as part of the call number, (3) material designation in physical description area or note area, (4) GMD and SMD. GMD is a term indicating the broad class of material to which a bibliographic item belongs. SMD is a term indicating the special class of material to which a bibliographic item belongs. GMD was listed in parenthesis following the title proper before AACR1975 code, but currently it is listed in square brackets after the AACR1975 code. AACR2 was the standard cataloging rule in GMD and SMD terminology. It is suggested that GMD be used in Korean for graphic material, sound recordings, drawings, microform, multimedia, videorecordings, manuscripts, photographs, slides, printed music, motion pictures, printed texts, objects, braille, cartographic materials, computer files and transparenies.

• Korean Journal of Human Ecology
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• v.9 no.2
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• pp.245-256
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• 2000

The purpose of this study is to identify the types of professional teaching practice of Home Economics teachers who are working at Korean secondary school for changing their professional teaching practice and developing home economics curriculum. A mail questionnaire, Professional Teaching Practice(PTP) was used to survey randomly selected 525 Home Economics teachers. The professional teaching practices examined were customary-instrumental, interactive and reflective practices. Customary-instrumental practice was the predominant type of professional teaching practice used by Home Economics teachers. About 26% of the teachers used reflective practice, and 14.67% used interactive practice. Only the number of students was significantly related to their professional teaching practices. Five influential factors on teaching practices identified by Home Economics teachers emerged in the following order: examination-centered educational system, lack of class hours, lack of resource materials and facilities, demands from the Ministry of Education, school administrators, or parents, and large class sizes.

• Journal of the Korean Operations Research and Management Science Society
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• v.21 no.3
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• pp.1-10
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• 1996

In this paper, the problem of simultaneously allocating servers and loadings of stations in a class of manufacturing systems modelled as network of queues is considered. The throughput function of the closed network of queues is demonstrated as a Schur convex function of server allocation, that is, increasing the server allocation vector under majorization increases the performance in the ship in terms of the throughput. It also reduces the congestion in the open network of queues in terms of reducing the total number of jobs in the sense of likelihood ratio ordering. These are the extentions of the numerical results of Green and Guha (1995) in the service system with independent M/M/c systems to the network of queues. The results can be used to support production planning in certain manufacturing systems.