• Journal of Communications and Networks
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• v.10 no.3
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• pp.351-361
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• 2008

This paper presents a delay-margin based traffic engineering (TE) approach to provide end-to-end quality of service (QoS) in multi-protocol label switching (MPLS) networks using differentiated services (DiffServ) at the link level. The TE, including delay, class, and route assignments, is formulated as a nonlinear optimization problem reflecting the inter-class and inter-link dependency introduced by DiffServ and end-to-end QoS requirements. Three algorithms are used to provide a solution to the problem: The first two, centralized offline route configuration and link-class delay assignment, operate in the convex areas of the feasible region to consecutively reduce the objective function using a per-link per-class decomposition of the objective function gradient. The third one is a heuristic that promotes/demotes connections at different links in order to deal with concave areas that may be produced by a trunk route usage of more than one class on a given link. Approximations of the three algorithms suitable for on-line distributed TE operation are also derived. Simulation is used to show that proposed approach can increase the number of users while maintaining end-to-end QoS requirements.

• Journal of Korean Elementary Science Education
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• v.33 no.3
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• pp.588-596
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• 2014

The purpose of this study is to provide basic data for improving the STEAM class by examining elementary school teachers' difficulties in the STEAM class and discussing solutions. For this research, 25 elementary school teachers in Seoul City and Gyeonggi-do were asked to write their difficulties in the STEAM class in the open-ended questionnaires. After classification of the collected data, an in-depth interview was conducted with one in-service elementary school teacher who is richly experienced in STEAM education to find solutions for each type of difficulties. The study result showed that most of elementary school teachers had difficulties in the STEAM class, due to selection of integrated subjects, production of teaching devices and materials, guidance of group activities, reorganization of the curriculum, assessment and uncooperative co-teachers. One teacher that participated in the interview to discuss solutions for teachers' difficulties was solving the problems in various ways. She said that many of her solutions came from her experience and also, knowledge obtained through a participation in the STEAM training or opportunities to share information with other teachers who belong to the STEAM research institution, was highly helpful.

• The Journal of the Korean dental association
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• v.16 no.11 s.114
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• pp.861-866
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• 1978

Study on the dental educational systems in New-Zealand. The following results was obtained. 1. Dental faculty system was 5 years course, only one school, Faculty of Dentistry University of Otago in Dunedin, New-Zealand. one class was 40 students. 2. Dental nursing school system was 2 years course and 3 dental nursing school in New-Zealand. (Auckland, Wellington, Christchurch) One class was each 30 students.

• Bulletin of the Korean Mathematical Society
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• v.49 no.1
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• pp.33-47
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• 2012

In this paper, the log-convexity of another class one-parameter mean is investigated. As applications, some new upper and lower bounds of logarithmic mean, new estimations for identric mean and new inequalities for power-exponential mean and exponential-geometric mean are first given.

• Management Science and Financial Engineering
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• v.17 no.2
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• pp.23-37
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• 2011

In this paper, we address a layout design problem for determining an optimal 4-class-based dedicated linear storage layout in a class of unit load storage systems. Assuming that space requirement for a class is the sum of the maximum inventory levels of products assigned to the class, and that one-way travel time is a linear function of storage index, we formulate a 4-class-based dedicated linear storage problem PTL[4] and provide an exact splitting algorithm with $O(n{\lceil}logn{\rceil})$. Our algorithms could be applied to more than a 4-class-based dedicated storage layout problem with slight modification in order to reduce computational execution time.

• Journal of Internet Computing and Services
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• v.19 no.5
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• pp.107-113
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• 2018

Object-oriented databases (OODBs) canbe used for many non-traditional database application areas such as computer-aided design, etc. Usually those application areas require advanced modeling power for expressing complicated relationships among data sets. OODBs have more distinguished features than the traditional relational database systems. One of the distinguished characteristics of OODBs is class hierarchy (also called inheritance hierarchy). A class hierarchy in an OODB means that a class can hand down the definitions of the class to the subclass of the class. In other words, a class is allowed to inherit the definitions of the class from the superclass. In this paper, we present performance evaluation metrics for class hierarchy in OODBs from a concurrency control perspective. The proposed performance metrics are developed to determine which concurrency control scheme in OODBs can be used for a given class hierarchy. In this study, in order to develop performance metrics, we use class hierarchy structure (both of single inheritance and multiple inheritance), and data access frequency for each class. The proposed performance metrics will be also used to compare performance evaluation for various concurrency control techniques.

• Journal of the Korean School Mathematics Society
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• v.10 no.4
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• pp.487-504
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• 2007

Although there was an introduction of the class with in mind learner's individual learning ability as a method improving problems of the class which consists of students with various kinds of levels, it was a burden to both teacher and students because of many realistic problems. In this paper, we investigate the efficiency of peer tutoring teaching method which is the one that students having a superior ability for learning become peer tutors and they teach other peer tutee under the teacher's guidance and supervision. After we apply the class-wide peer tutoring to some sophomore classes, we obtain that this teaching method affects positively the students's learning achievement and learning attitude in mathematics class. In particular, we obtain that the peer tutoring is more effective in three to one group than in one to one group.

• The Research Journal of the Costume Culture
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• v.7 no.5
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• pp.19-32
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• 1999

This paper examines Haniwa costume in the Goboon period of Japan. The results are as follows. 1. Haniwa costume consisted of two pieces, the upper one and the lower one. Man wore Jacket and Pants, woman wore Jacket and Skirt ; besides, they wore several ornaments such as hats, necklaces, earings, bracelets. 2. When it was introduced, two-piece costume signified, symbolically, the authority of the chieftain and his near men wore it. 3. Before it was introduced, their proper costume had been the same kind of costume as Whoengpok-costume and Gwandu-costume, which was the primitive costume in the South countries. That costume was fit both for the hot and wet nature of Japan and for the working lower-class, so it was continuously worn by the lower-class after two-piece costume had been introduced. 4. In the Goboon period of Japan, a unified government with the class ruling was established for the first time. Thus, this social order was reflected in costume as a whole, and costume had such class-oriented features.

• Journal of The Korean Association For Science Education
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• v.5 no.1
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• pp.19-34
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• 1985

Teaching inquiry process is one of the most important objectives in science education. To promote students scientific process skills, a science teacher should encourage the students do something by themselves. One method for that purpose which has been used in many schools would be group experiment. The researcher has been experienced a lot of difficulties in controlling or guiding every group to finish the assigned experiment within the given class hour. Therefore, the researcher decided to select several leaders from students and trained them in advance of the given class hour. This leaders are expected to guide the remaining students in the class. As the result of this study, the classroom with and without student leaders showed very significant difference(P>0.001) in their achievement of scientific process skills. The experimental group also showed more positive attitude toward science. The researcher concluded that the use of student leaders is very effective in promoting scientific process skills. This method is also regarded very effective in a large class sized like Korean Schools.

• English Language & Literature Teaching
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• v.8 no.1
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• pp.1-13
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• 2002

One of the benefits of the internet-assisted instruction is that it can improve L2 Learners' motivation to express themselves in English. The purpose of this paper is to investigate an effective approach to British-American fiction learning in Korean universities, which can emphasize communicative strategies drawing on video-conferencing system, a chat system(CUSeeMe), and an e-mail system. Students are passive participants who cannot assert their creativity in the traditional teaching method of British-American fiction, which mainly relies upon reading and translation far from literature lessons. In CCDL(Cross-cultural distance learning) class, students can play active roles in asserting their own ideas and assuming considerable responsibility for making a presentation in English. A professor can play a role as a coordinator in supporting the students' activities and in winding up the class. The main significance of this article lies in providing a paradigm for CCDL class beyond the limitation of the traditional teaching method of British-American fiction in Korea and futhermore in exploring the eclectic integration of the traditional one and CCDL.