• Journal of Communications and Networks
• /
• v.18 no.4
• /
• pp.589-599
• /
• 2016

Most existing resource management problem models arise from the original desire of allocating resources in either a user-centric or network-centric manner. The difference between their objectives is obvious: user-centric methods attempt to optimize the utility of individual users, whereas network-centric models intend to optimize the collective utilities of the entire network. In this paper, from the above two aspects, we analyze the robust power control problem in device-to-device (D2D) communication underlaying cellular networks, where two types of channel uncertainty set (e.g., ellipsoidal and column-wise) are considered. In the user-centric method, we formulate the problem into the form of a Stackelberg game, where the energy efficiency (EE) of each user is the ingredient of utility function. In order to protect the cellular user equipment's (CUE) uplink transmission, we introduce a price based cost function into the objectives of D2D user equipment (DUE). The existence and uniqueness of the game with the influence of channel uncertainty and price are discussed. In the network-centric method, we aim to maximize the collective EE of CUEs and DUEs. We show that by the appropriate mathematical transformation, the network-centric D2D power control problem has the identical local solution to that of a special case of the user-centric problem, where price plays a key role. Numerical results show the performance of the robust power control algorithms in the user-centric and network-centric models.

• Journal of the Korean Institute of Telematics and Electronics S
• /
• v.36S no.6
• /
• pp.67-75
• /
• 1999

The sensing and communication abilities of a mobile robot are essential to cooperative behavior in distributed autonomous robotic systems. In general, as the number of robot goes on increasing, the limitation of communication capacity and information overflow occur in global communication capacity and information overflow occur in global communication system. Therefore a local communication is more effective than global one. In this paper, we analyze information propagation mechanism based on local communication. To find an optimal communication radius, we propose three methods with different conditions. Also, to avoid chaotic behavior which occurs when a robot obtains and loses information, we find stable condition of information propagation.

• The Journal of the Convergence on Culture Technology
• /
• v.8 no.2
• /
• pp.83-89
• /
• 2022

Recentely, the military needs to apply various technologies for the improvement of teamwork. The government should take the non-face-to-face system due to the social interest of young military members. In this study we investigated collective cohesion by helping soldiers who have difficulty expressing their feelings and delivering messages while living in groups, or who are unable to adapt to group life due to psychological disorders such as relationship anxiety. We proposed the Multi-perspective Relationship Experience program as a new VR application. We showed feeling a sense of reality equivalent to the actual situation, interpersonal tension and social distance were significantly reduced, and communication, which was difficult to actually do, was naturally achieved. In addition, positive effects were confirmed on the sense of belonging and leadership among all participants. We will be effectively used in manpower management policies that improve the collective cohesion of soldiers and support the adaptability of the military environment in line with the rapidly changing social interaction method.

• Journal of Korean Theatre Studies Association
• /
• no.40
• /
• pp.125-162
• /
• 2010

This is the study on the 'Theater State' in the Daehan Empire of the Emperor Gochung in the late 1900 with the theatrical concepts of cultural performance theory which has been useful for investigating historical, social, and cultural collective memories and their transformation mechanism in the society. The performance theory is based in the notion, '$Performativit{\ddot{a}}t$', by which the performance can contain vary performance forms. $Performativit{\ddot{a}}t$ is the notion which points up the certain process that can cause the perceptional emotion communication to the performers and audiences in the performance. The spectacle of a society is also understood and presupposed by the $Performativit{\ddot{a}}t$. Generally speaking, the spectacle has been used of explaining the visual cultural experiences in society. Fundamentally, spectacle had resulted from the latin 'spectaculum', which was used to designate theatrical representation in France. In the case of movie, spectacle was the grand show with showy technological attractions. The spectacle have been to show the political and socio-historical relationships in a society. But in my study, I want to start the premise that the cultural performance planed by the Emperor Gochung in the Daehan Empire has the attribute of 'theater state', which can awaken the certain collective emotion to connect the Emperor and his people in the Daehan Empire period of the Emperor Gochung of the late 1900. In addition to it, I search for the historical collective memories of the Daehan Empire. The government of the Daehan Empire was continuing with its efforts to enforce and recollect the imperial images and authority of the Emperor and his Empire to get the approval of the people and international society. The effect of spectacle consisting of theater state was the concrete effort to establish the collective memories of the Daehan Empire by remodelling and rebuilding the Seoul, the capital of the Empire and performing the national ceremony such as the korean pagent(Gae-Dung거둥) and parade to set the portrait of the Emperor(A-Jin어진), the geo-body of the Empire.

• Proceedings of the Korean Information Science Society Conference
• /
• 2003.10a
• /
• pp.361-363
• /
• 2003

본 논문에서는 MPICH-G2의 집합 통신 중 가장 많이 이용되고 있는 브로드캐스트 함수의 통신 속도를 개선함으로써 분산 자원들의 통신속도를 높여 컴퓨팅 능력을 증가시켜주는 효과를 도모한다. 성능향상의 방법으로 패킷단위의 부분 데이터 송수신과 한 노드에서 여러 노드로 동시에 전송하는 두 가지 방법을 이용하였다. 제안된 방식을 사용했을 경우의 얻어지는 효과를 분석한 결과 데이터가 나뉘어진 패킷 수 p, 노드 수 n일 때, O(p$\times$n)에서 O(P＋n)로의 성능향상을 나타냈고. bandwidth가 작은 노드로 인해 발생하는 병목현상이 감소되는 것을 확인하였다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2009.11a
• /
• pp.159-160
• /
• 2009

하드웨어 기술이 발전하면서 단위 노드당 집적되는 CPU 수와 메모리량이 증가되어 단위 시스템의 성능이 크게 개선되었다. HPC 시스템도 SMP 시스템과 같은 고성능 노드를 사용하는 클러스터 시스템 위주로 발전하게 되었다. 본 연구에서는 IBM Power 595 기반 슈퍼컴퓨터에서 집합 통신이 갖는 특성을 알아 본다.

• Journal of Information Science Theory and Practice
• /
• v.1 no.2
• /
• pp.16-35
• /
• 2013

Relevance has a long history of scholarly investigation and discussion in information science. One of its notable concepts is that of 'user-based' relevance. The purpose of this study is to examine how users construct their perspective on the concept of relevance; to analyze what the constituent elements (facets) of relevance are, in terms of core-periphery status; and to compare the difference of constructions of two groups of users (information users vs. information professionals) as applied with a social representations theory perspective. Data were collected from 244 information users and 123 information professionals through use of a free word association method. Three methods were employed to analyze data: (1) content analysis was used to elicit 26 categories (facets) of the concept of relevance; (2) structural analysis of social representations was used to determine the core-periphery status of those facets in terms of coreness, sum of similarity, and weighted frequency; and, (3) maximum tree analysis was used to present and compare the differences between the two groups. Elicited categories in this study overlap with the ones from previous relevance studies, while the findings of a core-periphery analysis show that Topicality, User-needs, Reliability/Credibility, and Importance are configured as core concepts for the information user group, while Topicality, User-needs, Reliability/Credibility, and Currency are core concepts for the information professional group. Differences between the social representations of relevance revealed that Topicality was similar to User-needs and to Importance. Author is closely related to Title while Reliability/Credibility is linked with Currency. Easiness/Clarity is similar to Accuracy. Overall, information users and professionals function with a similar social collective of shared meanings for the concept of relevance. The overall findings identify the core and periphery concepts of relevance and their relationships in terms of coreness, similarity, and weighted frequency.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.9 no.7
• /
• pp.2488-2511
• /
• 2015

Data redundancy has high impact on Wireless Sensor Network's (WSN) performance and reliability. Spatial and temporal similarity is an inherent property of sensory data. By reducing this spatio-temporal data redundancy, substantial amount of nodal energy and bandwidth can be conserved. Most of the data gathering approaches use either temporal correlation or spatial correlation to minimize data redundancy. In Collective Prediction exploiting Spatio Temporal correlation (CoPeST), we exploit both the spatial and temporal correlation between sensory data. In the proposed work, the spatial redundancy of sensor data is reduced by similarity based sub clustering, where closely correlated sensor nodes are represented by a single representative node. The temporal redundancy is reduced by model based prediction approach, where only a subset of sensor data is transmitted and the rest is predicted. The proposed work reduces substantial amount of energy expensive communication, while maintaining the data within user define error threshold. Being a distributed approach, the proposed work is highly scalable. The work achieves up to 65% data reduction in a periodical data gathering system with an error tolerance of 0.6℃ on collected data.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.19 no.1
• /
• pp.115-121
• /
• 2009

Web 2.0 has become the face next generation Web among the business world and research community. Web 2.0 is instant superficial gratification of people. On the other hand, Semantic Web is deep, meaningful and lasting relationship with data. So, it is difficult to apply the Semantic Web to the real world. In this paper, a platform for educational services using the Semantic Web and Web 2.0 is proposed. The proposed platform is based mix of the Semantic Web and Web 2.0, so it is useful to apply in the real world applications. Two services are presented, one is a semantic email system and the other is a cyber study space. The cyber study space adjusted each student is presented. The study environment is called iStudySpace that has personal scheduler, study status plan table, personalized search engine and several gadgets. Finally characteristics and limitations of the Semantic Web and Web 2.0, the organization and components of the platform, evaluation of iStudySpace are shown.

• Spatial Information Research
• /
• v.14 no.3 s.38
• /
• pp.261-270
• /
• 2006

With the development and invention of computer and internet, GIS (Geographic Information System) has provided diverse services to users. Web 2.0, the next generation web, has been developed to create a new business by accumulating and structuring information from many users. The characteristics of Web 2.0 are blog, longtail distribution, SNS, DCC, collective intelligence, and so on. This study proposes a GIS 2.0 service model to maximize the introduction effect and use of GIS by the method that two-way communication and the participation of consumer, characteristics of Web 2.0, are used to build more practical GIS rather than providing spatial information in one-way and simple inquiry oriented way.