• Journal of The Korean Association For Science Education
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• v.19 no.3
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• pp.400-408
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• 1999

This study investigated the effect of the grouping method in cooperative learning applied to chemistry concept learning. Two grouping methods used were the HML (High-Medium-Low) and the HL/MM (High-Low/Medium-Medium) ability grouping. Three classes (N = 136) at a high school in Seoul were randomly assigned to the control and the treatment groups. Before instruction. the test of attitude toward science instruction, the perception questionnaire of learning environment consisting of three subtests (participation, conflict, and competition), and the questionnaire of self-esteem were administered, and a mid-term examination score was obtained. These scores were used as covariates. After instruction, the three tests administered before instruction and the conceptions test were administered. Two-way ANCOVA results revealed that there was a significant interaction between the treatment and the level of previous achievement. The low-level students in the HL/MM cooperative group performed better than those in the other groups. The cooperative groups, regardless of the grouping methods, exhibited more positive perception than the control group at participation subtest of the perception questionnaire of learning environment.

• Journal of Korean Home Economics Education Association
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• v.30 no.3
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• pp.91-109
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• 2018

This research aimed to develop teaching-learning plans applying character education components and STAD cooperative learning strategy focusing on the 'Housing and residential environment' unit in accordance with the 2009 revised Technology·Home Economics curriculum. In order to achieve the purpose of the research, this study was conducted in order of analysis, design, development, and evaluation. The results of this study is as follows. First, at the analysis stage, relevant literature, Technology·Home economics curriculum, and the contents of "housing and residential environment" unit from 12 textbooks published by 12 publishers were analyzed. Second, at the design stage, teaching-learning plans, teaching materials, and learning activity sheets applying character education components and STAD cooperative learning strategy were designed to increase the interest degree of the learner and character of middle school students. Third, at the development stage, a total of 8 classes of teaching-learning plan was developed. In the evaluation stage, the primary and secondary validity evaluation procedures were done by Home Economics education professors and Home Economics teachers. Teaching-learning plans and learning activity sheets were revised and complemented based on the feedback from the first validity evaluation. As a result of secondary validity evaluation, it can be seen that the teaching-learning plans and learning activity sheets developed in this research are reasonable and suitable for improving character of middle school students. It is expected that these teaching materials applying STAD and character education components will be utilized as a helpful source for curriculum developers and in-service teachers.

• Journal of Korea Multimedia Society
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• v.15 no.12
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• pp.1464-1474
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• 2012

In this paper, we propose a QoS (Quality of Service)-aware and cooperative resource reservation scheme using cross-layer link adaptation for wireless high definition video transmission through UWB (Ultra Wide Band) network with D-MAC (Distributed Medium Access Control). A wireless high definition video transmission system usually requires stable high throughput even without line-of-sight, e.g., a destination device in another room separated by a wall. Since the WiMedia D-MAC supporting DRP (Distributed Reservation Protocol) scheme causes lots of DRP resource reservation conflicts due to failure of beacon detection in wireless channel environment, overall performances of the WiMedia D-MAC can be deteriorated. And the current WiMedia MAC standard has not considered QoS provisioning even though QoS parameters such as a range of service rates are provided to each traffic stream. Therefore, we propose Relay DRP protocol with QoS-based relay node selection criterion, which makes a relay path to avoid DRP resource reservation conflicts and guarantee QoS more stably through cross-layer link adaptation of cooperative relay transmission scheme and is compliant with the current WiMedia D-MAC protocol. Simulation results demonstrate performance improvements of the proposed method for throughput and QoS provisioning.

• Strategy21
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• s.34
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• pp.5-25
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• 2014

On July 3~4, 2014, the Chinese President Xi Jinping's state visit to Seoul might be seen as a step on the path toward strategic outcomes for both country. For South Korea, Seoul shrewdly retains some degree of self-reliance by balancing between ROK-China strategic cooperative partnership relationship and ROK-US alliance. For China, Beijing appears to put its interests on the Korean Peninsula increasingly within China's larger geopolitical influence. To what extent can ROK-China relationship maintain futuristic strategic cooperative partnership between them? As we observed joint press communiques of the Chinese President Xi Jinping's state visit on July 3, 2014, four agendas of bilateral relationship between Seoul and Beijing can be identified: intractable rivalry between the two great powers, North Korea nuclear issues, disparities of their displeasure with Japan denying the past wrongdoing and enhancing its military capabilities and Chinese imposing of its core interests on its Korea policy. With these evolving strategic environments, however, China and the ROK appear justifiably be pleased with the state of their relations: their strategic cooperative partnership is the cornerstone of peace and prosperity in the Asia-Pacific or Indo-Pacific region and continues to grow broader and deeper.

• Journal of the Korean Institute of Intelligent Systems
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• v.11 no.7
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• pp.591-597
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• 2001

In this paper, we propose a method of cooperative control (T-cell modeling) and selection of group behavior strategy (B-cell modeling) based on immune system in distributed autonomous robotic system (DARS). Immune system is living body's self-protection and self-maintenance system. These features can be applied to decision making of optimal swarm behavior in dynamically changing environment. For applying immune system to DARS, a robot is regarded as a B-cell, each environmental condition as an antigen, a behavior strategy as an antibody and control parameter as a T-cell respectively. The executing process of proposed method is as follows. When the environmental condition changes, a robot selects an appropriate behavior strategy. And its behavior strategy is stimulated and suppressed by other robot using communication. Finally much stimulated strategy is adopted as a swarm behavior strategy. This control school is based on clonal selection and idiotopic network hypothesis. And it is used for decision making of optimal swarm strategy. By T-cell modeling, adaptation ability of robot is enhanced in dynamic environments.

• Smart Structures and Systems
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• v.26 no.1
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• pp.11-21
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• 2020

The hinge joint is the key to the overall cooperative working performance of the assembled beam bridge, and it is also the weakest part during the service period. This paper proposes a method for monitoring and evaluating the lateral cooperative working performance of fabricated beam bridges based on dynamic strain correlation coefficient indicator. This method is suitable for monitoring and evaluation of hinge joints status between prefabricated girders and overall cooperative working performance of bridge, without interruption of traffic and easy implementation. The remote cloud monitoring and diagnosis system was designed and implemented on a real assembled beam bridge. The algorithms of data preprocessing, online indicator extraction and status diagnosis were given, and the corresponding software platform and scientific computing environment for cloud operation were developed. Through the analysis of real bridge monitoring data, the effectiveness and accuracy of the method are proved and it can be used in the health monitoring system of such bridges.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.5
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• pp.61-65
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• 2014

In this paper, we propose a method using cooperative spectrum sensing to avoid multipath and frequency selective fading. One of methods in conventional scheme was multi input multi output (MIMO) solution. However, in the wireless environment, mobile device hardly supports multi antenna because of limitation of hardware. Motivated from above problems, the proposed method provides the information of excellent channel to transmitter. As a result, quality of service (QoS) required by users can be satisfied. Finally, performance of the proposed protocol is analyzed in term of bit error rate (BER).

• The Transactions of the Korea Information Processing Society
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• v.5 no.5
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• pp.1140-1150
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• 1998

The objective of this paper is to analyze requirements of distributed applications which use the different type of information and support the cooperative work environment between a group of persons in interactive mode, and to provide useful common services for the development of this kind of applications. For this, Interactive Cooperative Application Service as a horizontal service on the application layer and Session Management Service as a support service on the infrastructure layer were defined and designed using the concepts and rules of the Open Distributed Processing system. Application designers may use these services for building those applications which demand the requirements we have characterized in this paper.

• The KIPS Transactions:PartA
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• v.12A no.5 s.95
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• pp.433-440
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• 2005

The sharing of objects for authoring frequently occurs among participating users in a cooperative authoring system where many users can collaborate. Floor control is therefore needed not only for minimizing the race condition during object accesses but also for ensuring the exclusive use of objects. h floor is a temporary access right that is given to a participating user who wants to use a shared object. Although the floor control methods for a single session environment can be found in various literature, those methods for a multi-session environment can hardly be found. In a multi-session environment, an object can be shared by multiple sessions. As a solution to the problems due to object sharing in such an environment, this paper presents a floor control method based on the chair-of-chair guidance. This method is an extension of those based on traditional chair guidance; the chair-of-chair elected among session chairs exists in this method.

• Journal of The Korean Association For Science Education
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• v.17 no.2
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• pp.139-148
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• 1997

This study investigated the influences of the cooperative learning strategies upon students' achievement and their perceptions of learning environments in a middle school physical science course. Prior to instruction, the Group Assessment of Logical Thinking was administered, and its score was used as a blocking variable. Mid-term examination score was used as a covariate. For the treatment group with heterogeneous grouping, cooperative learning instruction (the Learning Together model) was used, which emphasized group reward, individual accountability, and role division. For the control group, traditional instruction was used. After instruction, an achievement test consisting of three subtests (knowledge, understanding, and application), and the perception questionnaire of classroom and laboratory environments, were administered. ANCOVA results revealed that there was a significant interaction between instruction and the level of logical reasoning ability although there were no significant differences in all three subtest scores of the achievement test. For the concrete operational reasoners, the treatment group performed better in the subtests of understanding and application than the control group. For students at the formal and transition levels, however, the treatment group scored lower than the control group. Significant interactions were also found in the perceptions of classroom environment and laboratory environment. For the concrete operational reasoners, the treatment group showed more positive perception than the control group. For the students at the formal and transition levels, the control group had positive perception than the treatment group. Educational implications are discussed.