• Title/Summary/Keyword: Global Mobility

Search Result 187, Processing Time 0.031 seconds

Dual Addressing Scheme in IPv6 over IEEE 802.15.4 Wireless Sensor Networks

  • Yang, Soo-Young;Park, Sung-Jin;Lee, Eun-Ju;Ryu, Jae-Hong;Kim, Bong-Soo;Kim, Hyung-Seok
    • ETRI Journal
    • /
    • v.30 no.5
    • /
    • pp.674-684
    • /
    • 2008
  • This paper proposes a dual addressing scheme (DAS) for IPv6 over IEEE 802.15.4 wireless sensor networks (WSN). DAS combines a global unicast address to cope with association link changes and node mobility, and it links local addresses to lighten the overhead of the system to save energy and resources. This paper describes DAS address formats, address autoconfiguration, and address translation tables in the gateway. A detailed description of DAS is provided through examples. Simulations are performed to demonstrate the performance improvements of the DAS compared with the IPv6-based WSN, which uses the conventional single address.

  • PDF

An Engine Structure-Borne Noise Analysis by Finite Element Method (유한요소법에 의한엔진 구조소음 해석)

  • 안상호;김주연;김규철
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.6 no.1
    • /
    • pp.122-133
    • /
    • 1998
  • This paper presents the static analysis, the modal analysis and the forced vibration analysis on engine structures to find out the structure-borne noise sources by finite element method. The deformation of engine structures under the maximum combu- stion gas force was calculated through the static analysis, and the resonance possibilities were predicted by the modal analysis which ascertains mode shapes and the corresponding frequencies of engine global and its major noise sources in engine surfaces were investigated with the forced vibration analysis by means of finding the transfer mobilities on engine surfaces due to the piston impact and the velocity levels due to the combustion in consideration of oil film stiffness and damping coefficients. Finally, the direction of engine structure-borne noise reduction can be estabilished by the above-mentioned analysis procedure and the reduction effect of cost on proto-type engine build-up is expected.

  • PDF

Defining 'Islamic' Urbanity Through A Trans-Regional Frame

  • Mukhopadhyay, Urvi
    • Asian review of World Histories
    • /
    • v.3 no.1
    • /
    • pp.113-135
    • /
    • 2015
  • The word 'urbanity' literally means 'quality or state of being urban' where the criterion of urban economic and civic culture is assumed despite the general celebration of cultural uniqueness of urban centers. The narratives celebrating the uniqueness of urban centers since the ancient past till recent times could not get rid of the broad categorization of the urban models depending on their contextual networks of trade, mobility and culture. This paper attempts to explore whether the urban cultures in South Asia even preceding a global phenomenon like colonialism were actually reflecting an idea of urbanity where the urban culture, including planning and architecture reflected a trans-national model. This paper particularly concentrates on the medieval period when a pattern of urbanity took shape in this subcontinent under the influence of Islam, which could be explained by its particular idea of urban model, cultural exchange and vibrant trade networks.

The Development of the Korean Motor Vehicle Safety Standards for Windscreen Wiper Systems of Motorcycles (이륜자동차 창닦이기장치 등의 국내안전기준 개발)

  • Han, Kyeonghee
    • Journal of Auto-vehicle Safety Association
    • /
    • v.9 no.3
    • /
    • pp.39-45
    • /
    • 2017
  • Two-wheeled motorcycles rarely use windscreen wipers in general. However, if two or more wheeled motorcycles with upper body employ windscreen wiper systems, clear visibility should be ensured regardless of weather conditions. The windscreen wiper systems include washers, defrosting, and demisting. As demands for the personal mobility are rapidly increased, the related global safety standards for motorcycles with upper body have been revised accordingly. Currently only EU regulations issue the provisions of windscreen wiper systems for L-category vehicles, which characterize two or more wheeled motorcycles. Therefore, in order to agree with international safety standards, it is necessary to revise KMVSS (Korea Motor Vehicle Safety Standards) for motorcycles. Here, KMVSS regarding windscreen wiper systems for motorcycles are studied considering the EU regulations. It is expected that the findings in this study are useful for future amendment of KMVSS.

Developments of a Path Planning Algorithm and Simulator for Unmanned Ground Vehicle (무인자율차량을 위한 경로계획 알고리즘 및 시뮬레이터 개발)

  • Kim, Sang-Gyum;Kim, Sung-Gyun;Lee, Yong-Woo
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.15 no.3
    • /
    • pp.1-9
    • /
    • 2007
  • A major concern for Autonomous Military Robot in the rough terrain is the problem of moving robot from an initial configuration to goal configuration. In this paper, We generate a local path to looking for the best route to move an goal configuration while avoiding known obstacle from world model, not violating the mobility constraints of robot. Trough a Simulator for Unmanned Autonomous Vehicle, We can simulate a traversability of unmanned autonomous vehicle based on steering, acceleration, braking command obtained from local path planning.

An Abstract Machine for a Located Process Model (위치 지정 프로세스 모델의 추상기계)

  • 신승철;최진영;변석우
    • Journal of KIISE:Software and Applications
    • /
    • v.26 no.2
    • /
    • pp.325-325
    • /
    • 1999
  • This paper presents a locally deterministic abstract machine for a new process model LocPi which is based on a subset of asynchronous polyadic π-calculus and enriched with locations and process mobility. Our calculus has a primitive for migrating and spawning a process to a location(remote site), but does not explicitly represent the place which a process are running at. Running processes may have names attached with their locations and the communication reductions can occur only on located names. So we present how to assign locations to unlocated names. Without a global channel environment, these located names enable us to locate the place which input actions occur at and output messages should be sent to.

A Study on the Configuration Control of a Mobile Manipulator Based on the Optimal Cost Function

  • Kang Jin-Gu;Lee Kwan-Houng
    • Journal of information and communication convergence engineering
    • /
    • v.3 no.1
    • /
    • pp.33-37
    • /
    • 2005
  • One of the most important feature of the Mobile Manipulator is redundant freedom. Using the redundant freedom, Mobile Manipulator can move various mode, perform dexterous motion. In this paper, to improve robot job ability, as two robots perform a job in co-operation control, we studied optimal position and posture of Mobile Manipulator with minimum movement of each robot joint. Kinematics of mobile robot and task robot is solved. Using mobility of Mobile robot, weight vector of robots is determined. Using Gradient methode, global motion trajectory is minimized. so the job which Mobile Manipulator perform is optimized. The proposed algorithm is verified with PURL-II which is Mobile Manipulator combined Mobile robot and task robot. and discussed the result.

Mobility of Microplastics in Subsurface Environments: Current Knowledge and Perspectives (지중환경에서 미세플라스틱의 이동성에 대한 고찰)

  • Kim, Youn-Tae;Han, Weon Shik;Yoon, Hye-On
    • Journal of Soil and Groundwater Environment
    • /
    • v.24 no.3
    • /
    • pp.1-12
    • /
    • 2019
  • Plastics have become essential materials in human life for several decades. Meanwhile, the inadvertent spread of plastic debris from the use of many plastic products has raised global environmental concerns. The risk of microplastics in subsurface environment has received little attention because soil is considered to confine microplastics within the matrix. However, the concentration of microplastics in soil unavoidably increased as a result of an increase in plastic production and use. Based on lab experiments, several researches claimed that microplastics possibly penentrate soil layers. Recently, a few researches reported the occurrence of microplastics in groundwater. This study reviewed the recent reports of microplastic occurrences in soil and groundwater, and the modeling studies for simulating transport of microplastics. Additionally, the difficulties and limits in microplastics researches in soil and groundwater are discussed. Finally, several perspectives on microplastic studies in subsurface environment are suggested.

GPS-Based Shortest-Path Routing Scheme in Mobile Ad Hoc Network

  • Park, Hae-Woong;Won, Soo-Seob;Kim, So-Jung;Song, Joo-Seok
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • 2004.05a
    • /
    • pp.1529-1532
    • /
    • 2004
  • A Mobile Ad Hoc NETwork (MANET) is a collection of wireless mobile nodes that forms a temporary network without the need for any existing network infrastructure or centralized administration. Therefore, such a network is designed to operate in a highly dynamic environment due to node mobility. In mobile ad hoc network, frequent topological changes cause routing a challenging problem and without the complete view of the network topology, establishing the shortest path from the source node to the destination node is difficult. In this paper, we suggest a routing approach which utilizes location information to setup the shortest possible path between the source node and the destination node. Location information is obtained through Global Positioning System (GPS) and this geographical coordinate information of the destination node is used by the source node and intermediate nodes receiving route request messages to determine the shortest path to the destination from current node.

  • PDF

Privacy Weakness Analysis of Delegation-Based Authentication Protocol (위임기반 인증 프로토콜의 프라이버시 취약성 분석)

  • Youn, Taek-Young;Kim, Chang-Han
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.20 no.6
    • /
    • pp.53-57
    • /
    • 2010
  • Recently, Lee et al. proposed a delegation-based authentication protocol for secure and private roaming service in global mobility networks. In this paper, we show that the protocol cannot protect the privacy of an user even though the protocol provides the user anonymity. To prove the weakness, we show that the protocol cannot provide the unlinkability and also examine the weakness of the protocol caused by the lack of the unlinkability.