• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.4
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• pp.1256-1275
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• 2014

As one of the new self-organizing and self-configuration broadband networks, wireless mesh networks are being increasingly attractive. In order to solve the load balancing problem in wireless mesh networks, this paper proposes a novel multi-path routing algorithm based on clustering (Cluster_MMesh) for wireless mesh networks. In the clustering stage, on the basis of the maximum connectivity clustering algorithm and k-hop clustering algorithm, according to the idea of maximum connectivity, a new concept of node connectivity degree is proposed in this paper, which can make the selection of cluster head more simple and reasonable. While clustering, the node which has less expected load in the candidate border gateway node set will be selected as the border gateway node. In the multi-path routing establishment stage, we use the intra-clustering multi-path routing algorithm and inter-clustering multi-path routing algorithm to establish multi-path routing from the source node to the destination node. At last, in the traffic allocation stage, we will use the virtual disjoint multi-path model (Vdmp) to allocate the network traffic. Simulation results show that the Cluster_MMesh routing algorithm can help increase the packet delivery rate, reduce the average end to end delay, and improve the network performance.

• Journal of KIISE:Computing Practices and Letters
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• v.5 no.6
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• pp.700-707
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• 1999

본 논문에서는 GIS 관련 연산을 실시간에 효율적으로 처리하기 위한 분산공유메모리 기반 병렬처리 시스템을 제안한다. 본 논문의 분산공유메모리 시스템은 메시지전달 방식의 분산메모리 MIMD 컴퓨터 상에 소프트웨어 기반 분산공유메모리 모듈을 탑재함으로써 구현되었다. 또한 GIS 연산의 기본이 되는 공간 객체를 공유의 기본 단위로 설정하고, GIS 데이타의 특성을 반영하여 읽기전용 공유데이타 타입을 추가하였으며, 네트워크 오버헤드를 줄이기 위하여 복수의 객체를 한번에 읽어오는 bulk access가 가능하도록 하였다. 본 시스템에서는 GIS 데이타의 효율적인 분배를 위하여 부하균등화 기법으로 guided self scheduling을 사용하였다. 실험결과 본 시스템은 네트워크 캐쉬의 효율적인 활용을 통하여 소프트웨어 기반 분산메모리 시스템의 오버헤드에도 불구하고 MPI 기반 메시지전달 방식에 비하여 향상된 성능을 얻을 수 있었다.Abstract In this paper, we propose a distributed shared memory(DSM) based parallel processing system to process GIS related computations efficiently in real time. The system is based on a software DSM module implemented on top of a distributed MIMD computer. In the DSM system, spatial object, which is a fundamental structure to represent GIS data, is used as a basic unit for sharing, and a read-only shared data type is added to reflect the characteristics of GIS data. In addition, a bulk access to multiple shared data is made possible to reduce the network overhead. A guided self scheduling method is devised for efficient load balancing in distributing GIS data to parallel processors. The experimental results show that the DSM system performs better than an MPI based message-passing system through the efficient utilization of network cache in spite of the system's software overhead.

• The Journal of the Korea Contents Association
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• v.18 no.11
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• pp.379-392
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• 2018

The purpose of this study is to investigate the impact and significance of married women's graduate school experiences, as well as to assess the differences in the images of a model woman and that of a real life married woman, and their implications in the aspect of social policies. Results showed that the reason married women enter graduate schools are psychological conflicts, feeling of emptiness, and self motivation for self realization. It was also found that once married women are in graduate school, they are faced with many difficulties such as balancing work and family lives, dealing with academic difficulties and physical / economic obstacles as they struggle to continue their studies. After exploring how the study participants overcame their difficulties and accomplished changes in their lives with the best use of available resources such as firm willingness to continue their studies and support from family and friends, this researcher wishes to present a sound guidance resulting from this study to married women who are preparing for graduate school.

• 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 Korea Computer Graphics Society
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• v.4 no.2
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• pp.1-13
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• 1998

The most important goal of character animation is to efficiently control the motions of a character. Until now, many techniques have been proposed for human gait animation, and some techniques have been created to control the emotions in gaits such as "tired walking" and "brisk walking" by using parameter interpolation or motion data mapping. This paper proposes a human running model based on a one-legged hopper with a self-balancing mechanism. The proposed technique exploits genetic programming to optimize movement, and can be easily adopted to various character models. We extend the energy minimization technique to generate various motions in accordance with emotional specification.

• Korean Journal of Adult Nursing
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• v.20 no.1
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• pp.113-125
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• 2008

Purpose: This research was conducted to explore the experiences of graduate student women with children fulfilling multiple roles and to generate a substantive theory. Methods: This study uses the grounded theory method based on Strauss and Corbin(1988)'s method. Interviews were conducted with 11 graduate student women who had children aged three of older. Results: The core category of this research is 'Role balancing for self-generativity'. Based on the core category, three types of married women graduate students' experiences were found. They are 'concentrating on graduate-work' 'postponing graduate-work' and 'adjustment between two roles' Conclusions: Through understanding the married women's multiple roles experience process, there can be a basis for making a women's health system and social support system for the married women graduate student. Also, this research is to generate a substantive theory which can helps to change social perspectives on the quality of life for the women who will contribute in Korean society as professionals.

• Women's Health Nursing
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• v.24 no.4
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• pp.379-391
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• 2018

Purpose: To describe nursing students' experience of sexual harassment during clinical practicum. Methods: An interpretive phenomenological qualitative approach was used to understand contextual experiences of participants. Individual in-depth interviews were conducted to collect data from thirteen nursing students who experienced sexual harassment during clinical practice in general hospitals at D metropolitan city. All interviews were recorded and transcribed into Korean and English. Transcripts were analyzed using the data analysis method described by Diekelmann, Allen, and Tanner. Results: The following 12 themes emerged from the data: 'unprepared to respond', 'lack of education', 'unsure about when behavior crosses the line', 'power differential for nursing students', 'balancing self-preservation with obligations to patients', 'shame', 'feeling responsible for not being able to prevent the harassment', 'impact on patient care', 'fear of what might have happened', 'fear of repercussions', 'long term impact', and 'peer support'. Conclusion: Participants in this study described feeling an obligation to care for their patients. However, they seemed to be unable to balance this while feeling vulnerable to sexual harassment with strong negative feelings. Helping students recognize and effectively deal with sexual harassment is a critical element to assure quality learning for participants and maintain quality of care during clinical practice.

• Journal of Information Technology Services
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• v.20 no.2
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• pp.77-90
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• 2021

Online and mobile games represent digital entertainment. Not only the game grows fast, but also it has been noted for unique business models such as a subscription revenue model and free-to-play with partial payment. But, a recent revenue mechanism, called a loot-box system, has been criticized due to overspending, weak protection to teenagers, and more over gambling-like features. Policy makers and research communities have counted on expert opinions, review boards, and temporal survey studies to build countermeasures to minimize negative effects of online and mobile games. In this process, speed was not seriously considered. In this study, we attempt to use a big data source to find a way of observing a trend for policy makers and researchers. Specifically, we tried to apply the Word2Vec data mining algorithm to news repositories. From the findings, we acknowledged that the suggested design would be effective in lightening issues timely and precisely. This study contributes to digital entertainment service communities by providing a practical method to follow up trends; thus, helping practitioners have concrete grounds for balancing public concerns and business purposes.

• Current Optics and Photonics
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• v.7 no.4
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• pp.419-427
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• 2023

The structural design of an optical-telescope assembly (OTA) for satellite laser ranging (SLR) is conducted in two steps. First, the results of a parametric study of the major design variables (e.g. dimension and shape) of the OTA part are explained, and the detailed structural design of the OTA is derived, considering the design requirements. Among the structural-shape concepts of various OTAs, the Serrurier truss concept is selected in this study, and the collimation of the telescope according to the design variables is extensively discussed. After generating finite-element models for different structural shapes, self-gravity analyses are performed. To minimize the deflection and tilt of the mirror and frame for the OTA under the limited design requirements, a parametric study is conducted according to design variables such as the shapes of the upper and lower struts and the spider vane. The structural features found in the parametric study are described. Finally, the OTA structure is designed in detail to maintain the optical alignment by balancing the gravity deflections of the upper and lower trusses using the optimal combination of the parameters. Additionally, thermal analysis of the optical telescope design is evaluated.

• IEMEK Journal of Embedded Systems and Applications
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• v.19 no.2
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• pp.107-114
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• 2024

Mobile ad hoc networks represent self-configuring networks of mobile devices that communicate without relying on a fixed infrastructure. However, traditional routing protocols in such networks encounter challenges in selecting efficient and reliable routes due to dynamic nature of these networks caused by unpredictable mobility of nodes. This often results in a failure to meet the low-delay and low-energy consumption requirements crucial for such networks. In order to overcome such challenges, our paper introduces a novel multi-objective and adaptive routing scheme based on the Q-learning reinforcement learning algorithm. The proposed routing scheme dynamically adjusts itself based on measured network states, such as traffic congestion and mobility. The proposed approach utilizes Q-learning to select routes in a decentralized manner, considering factors like energy consumption, load balancing, and the selection of stable links. We present a formulation of the multi-objective optimization problem and discuss adaptive adjustments of the Q-learning parameters to handle the dynamic nature of the network. To speed up the learning process, our scheme incorporates informative shaped rewards, providing additional guidance to the learning agents for better solutions. Implemented on the widely-used AODV routing protocol, our proposed approaches demonstrate better performance in terms of energy efficiency and improved message delivery delay, even in highly dynamic network environments, when compared to the traditional AODV. These findings show the potential of leveraging reinforcement learning for efficient routing in ad hoc networks, making the way for future advancements in the field of mobile ad hoc networking.