• Title/Summary/Keyword: global networks

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A novel approach to design of local quantizers for distributed estimation

  • Kim, Yoon Hak
    • Journal of IKEEE
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    • v.22 no.3
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    • pp.558-564
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    • 2018
  • In distributed estimation where each node can collect only partial information on the parameter of interest without communication between nodes and quantize it before transmission to a fusion node which conducts estimation of the parameter, we consider a novel quantization technique employed at local nodes. It should be noted that the performance can be greatly improved if each node can transmit its measurement to one designated node (namely, head node) which can quantize its estimate using the total rate available in the system. For this case, the best strategy at the head node would be simply to partition the parameter space using the generalized Lloyd algorithm, producing the global codewords, one of which is closest to the estimate is transmitted to a fusion node. In this paper, we propose an iterative design algorithm that seeks to efficiently assign the codewords into each of quantization partitions at nodes so as to achieve the performance close to that of the system with the head node. We show through extensive experiments that the proposed algorithm offers a performance improvement in rate-distortion perspective as compared with previous novel techniques.

Review on the Approaches and Issues in the field of Health Education in National Information Infrastructure (초고속정보통신망을 이용한 보건교육 활용방안)

  • 김은주
    • Korean Journal of Health Education and Promotion
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    • v.13 no.1
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    • pp.45-51
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    • 1996
  • The Korea Information Infrastructure aims at the construction of an advanced national information infrastructure, consisting of communication networks, computers, databases and multimedia terminals. In the emerging information society, a well-established national information network plays a crucial role in enhancing economic efficiency and creating national wealth. Till 2015, government plans to construct an Information Superhighway Network and to provide a telecommunication service for speedy transmission of multi-media typed information and development of various applied programs, which help government's commitment to establish nationwide infrastructure to perform a leading role as a high level information society in the 21st century. In the field of health education, the research monograph contains three main parts: health education and information, acceptability of health education; development of health education management information system. In the most remote areas, it can bring high-quality health care where none is now available. In global health care, it can enhance and standardize the quality of medical care throughout the world. Before enlarging the establishment of the health education network system, the issues from this study should be considered to improve the health status through the introduction of information technology and applications in health care.

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BILBO Network: a proposal for communications in aircraft Structural Health Monitoring sensor networks

  • Monje, Pedro M.;Aranguren, Gerardo
    • Structural Monitoring and Maintenance
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    • v.1 no.3
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    • pp.293-308
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    • 2014
  • In the aeronautical environment, numerous regulatory and communication protocols exist that cover interconnection of on-board equipment inside the aircraft. Developed and implemented by the airlines since the 1960s, these communication systems are reliable, strong, certified and able to contact different sensors distributed throughout the aircraft. However, the scenario is slightly different in the structural health monitoring (SHM) field as the requirements and specifications that a global SHM communication system must fulfill are distinct. The number of SHM sensors installed in the aircraft rises into the thousands, and it is impossible to maintain all of the SHM sensors in operation simultaneously because the overall power consumption would be of thousands of Watts. This design of a new communication system must consider aspects as management of the electrical power supply, topology of the network for thousands of nodes, sampling frequency for SHM analysis, data rates, selected real-time considerations, and total cable weight. The goal of the research presented in this paper is to describe and present a possible integration scheme for the large number of SHM sensors installed on-board an aircraft with low power consumption. This paper presents a new communications system for SHM sensors known as the Bi-Instruction Link Bi-Operator (BILBO).

Challenges and Outlook for the UICC-Asian Regional Office

  • Akaza, Hideyuki
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.8
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    • pp.4935-4937
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    • 2013
  • At the United Nations High-level Meeting on Non-communicable Disease Prevention and Control in 2011 the link between health and socioeconomic issues was raised, becoming a global political issue. Health equity is one challenge that has hitherto not been addressed directly, although there is a growing shared recognition that cancer in Asia is an urgent social issue. At the UICC-ARO we are working to promote and widen networks of individuals and organizations in Asia and involve them in cooperation for this purpose. As part of our current activities, we are addressing the question of the "Economic burden of cancer in Asian countries: How should we face the current situation?" from a variety of angles and seeking to bring together a wealth of multidisciplinary knowledge about cancer in Asia and its related socioeconomic factors. It is essential to ensure that the real picture of cancer in Asia, which is currently not accurately understood, is conveyed clearly to all concerned, and also that the differences between cancer in Asia and in the West are highlighted.

A Study on improving the Performance of Transshipment Cargo System at the Port of Busan

  • Bae, Suk-Tae
    • Journal of Korea Multimedia Society
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    • v.17 no.12
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    • pp.1503-1510
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    • 2014
  • This study will examine the consolidation that is occurring in the shipping industry and its effects on Busan's status as a key transshipment hub in Southeast Asia as well as what measures the port must implement to attract transshipment traffic. With this in mind heading forward, trends in transshipment cargo, problems facing the port, as well as the current status of transshipment volumes at the Port of Busan must be fully understood so that thorough research can be done into appropriate measures to stimulate growth and attract cargo traffic. In this study, We analyze the current problems and status of transshipment cargo at Busan Port and factors affecting the competitiveness of transshipment cargo at Busan New Port, Korea's key import/export gateway, have been examined. We show the Strategies to Attract Transshipment Cargo at the Busan New Port which is to become a an optimal transshipment port, a port's internal environment including the scale and location of its hinterland, facilities and tariffs as well as the external environment including global networks and logistics IT management must be carefully considered as they are all key actors affecting cargo volumes.

Design and Implementation of a Content Manager in the Multimedia Steaming Framework (멀티미디어 스트리밍 프레임워크에서 컨텐츠 관리자의 설계 및 구현)

  • Hong, Yeong-Rae;Kim, Hyeong-Il;Lee, Seung-Ryong;Jeong, Byeong-Su;Yun, Seok-Hwan;Jeong, Chan-Geun
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.2S
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    • pp.733-743
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    • 2000
  • This paper describes design and implementation of a content manager in the Integrated Steaming Framework Architecture (ISSA) that is proposed by the authors. The ISSA can provide an environment to develop multimedia streaming applications under heterogeneous distributed systems. The goal of ISSA is to extend the limitations of existing streaming systems. It can support diverse media formats and high level programming environment for streaming application developers. Moreover, it is independent from underlying networks and operating systems, and compatible with the global real-time multimedia database system(BeeHive) so that streaming media is efficiently retrieved, stored, and serviced. The role of a content manager is important in the ISSA environment since it manages an information of media that are provided by the server, and allow users to access media more easily by means of conveying that information to the streaming server, Web server, and client efficiently. The proposed content manager is not only to meed these requirements, but also to provide streaming information to media source and transport manager in order to be an efficient streaming. Furthermore, it supports database transaction processing by using the database connector.

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A Study on USIM-based Authentication Testbed for UMTS-WLAN Handover (UMTS-WLAN간 핸드오버를 위한 USIM 기반의 인증 테스트베드에 관한 연구)

  • Ro, Kwang-Hyun;Kwon, Hye-Yeon
    • Journal of the Institute of Convergence Signal Processing
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    • v.10 no.1
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    • pp.66-71
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    • 2009
  • In view of mutual complementary feature of wide coverage and high data rate, the interworking between 3G cellular network and WLAN is a global trend of wireless communications. This paper introduces the analytic result of an authentication mechanism for 3GPP-WLAN seamless mobility under the USIM-based authentication test-bed. In a handover process between heterogeneous networks, authentication is the main factor of handover delay. So authentication processing time should be firstly reduced. This paper describes an USTM-based EAP-AKA test-bed implemented for handover in UMTS and WLAN interworking systems. Experimental result has shown that the fast re-authentication mechanism during handover has reduced the handover delay by about 48.6%.

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Comparative Research of Fog Using the Regular Observation and GPS Integrated Water Vapor (정규관측자료와 GPS 연직누적 수증기량을 이용한 안개에 대한 비교연구)

  • Lee, Jaewon;Cho, Jungho;Baek, Jeongho;Park, Jong-Uk;Park, Chieup
    • Atmosphere
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    • v.18 no.4
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    • pp.417-427
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    • 2008
  • In this paper, we analyzed the physical and thermodynamic characteristics of fog by using the integrated water vapor (IWV) from Global Positioning System (GPS) networks and the regular observation data of meteorological stations in GPS sites. The cases of a radiation and an advection fog were selected as samples, the conversions of water substance from the water vapor to cloud water in fog were detected by the Bulk Water-Continuity Model, and the pattern analysis is adapted on GPS IWV, temperature, wind and relative humidity. Under the specific hypothesis (saturation and stable), GPS IWV could detect quantitatively the phase changing between the water vapor and cloud water content with condensation/evaporation during the formation and dissipation of fog. After it reaches to the saturation, the relative humidity can be a limited indicator for fog. However, GPS IWV can detect the status change of fog even after the saturation. It has indicated that GPS IWV could be a new observing technique for the processes of the fog formation and the dissipation.

Machine-to-Machine Communications: Architectures, Standards and Applications

  • Chen, Min;Wan, Jiafu;Li, Fang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.2
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    • pp.480-497
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    • 2012
  • As a new business concept, machine-to-machine (M2M) communications are born from original telemetry technology with the intrinsic features of automatic data transmissions and measurement from remote sources typically by cable or radio. M2M includes a number of technologies that need to be combined in a compatible manner to enable its deployment over a broad market of consumer electronics. In order to provide better understanding for this emerging concept, the correlations among M2M, wireless sensor networks, cyber-physical systems (CPS), and internet of things are first analyzed in this paper. Then, the basic M2M architecture is introduced and the key elements of the architecture are presented. Furthermore, the progress of global M2M standardization is reviewed, and some representative applications (i.e., smart home, smart grid and health care) are given to show that the M2M technologies are gradually utilized to benefit people's life. Finally, a novel M2M system integrating intelligent road with unmanned vehicle is proposed in the form of CPS, and an example of cyber-transportation systems for improving road safety and efficiency are introduced.

Learning the Covariance Dynamics of a Large-Scale Environment for Informative Path Planning of Unmanned Aerial Vehicle Sensors

  • Park, Soo-Ho;Choi, Han-Lim;Roy, Nicholas;How, Jonathan P.
    • International Journal of Aeronautical and Space Sciences
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    • v.11 no.4
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    • pp.326-337
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    • 2010
  • This work addresses problems regarding trajectory planning for unmanned aerial vehicle sensors. Such sensors are used for taking measurements of large nonlinear systems. The sensor investigations presented here entails methods for improving estimations and predictions of large nonlinear systems. Thoroughly understanding the global system state typically requires probabilistic state estimation. Thus, in order to meet this requirement, the goal is to find trajectories such that the measurements along each trajectory minimize the expected error of the predicted state of the system. The considerable nonlinearity of the dynamics governing these systems necessitates the use of computationally costly Monte-Carlo estimation techniques, which are needed to update the state distribution over time. This computational burden renders planning to be infeasible since the search process must calculate the covariance of the posterior state estimate for each candidate path. To resolve this challenge, this work proposes to replace the computationally intensive numerical prediction process with an approximate covariance dynamics model learned using a nonlinear time-series regression. The use of autoregressive time-series featuring a regularized least squares algorithm facilitates the learning of accurate and efficient parametric models. The learned covariance dynamics are demonstrated to outperform other approximation strategies, such as linearization and partial ensemble propagation, when used for trajectory optimization, in terms of accuracy and speed, with examples of simplified weather forecasting.