• Title/Summary/Keyword: Mobility

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Performance Improvement of Delay-Tolerant Networks with Mobility Control under Group Mobility

  • Xie, Ling Fu;Chong, Peter Han Joo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.6
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    • pp.2180-2200
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    • 2015
  • This paper considers mobility control to improve packet delivery in delay-tolerant networks (DTNs) under group mobility. Based on the group structure in group mobility, we propose two mobility control techniques; group formation enforcement and group purposeful movement. Both techniques can be used to increase the contact opportunities between groups by extending the group's reachability. In addition, they can be easily integrated into some existing DTN routing schemes under group mobility to effectively expedite the packet delivery. This paper is divided into 2 parts. First, we study how our proposed mobility control schemes reduce the packet delivery delay in DTNs by integrating them into one simple routing scheme called group-epidemic routing (G-ER). For each scheme, we analytically derive the cumulative density function of the packet delivery delay to show how it can effectively reduce the packet delivery delay. Then, based on our second proposed technique, the group purposeful movement, we design a new DTN routing scheme, called purposeful movement assisted routing (PMAR), to further reduce the packet delay. Extensive simulations in NS2 have been conducted to show the significant improvement of PMAR over G-ER under different practical network conditions.

Mobility Determination of Thin Film a-Si:H and poly-Si

  • Jung, S.M.;Choi, Y.S.;Yi, J.S.
    • Journal of Sensor Science and Technology
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    • v.6 no.6
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    • pp.483-490
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    • 1997
  • Thin film Si has been used in sensors, radiation detectors, and solar cells. The carrier mobility of thin film Si influences the device behavior through its frequency response or time response. Since poly-Si shows the higher mobility value, a-Si:H films on Mo substrate were subjected to various crystallization treatments. Consequently, we need to find an appropriate method in mobility measurement before and after the anneal treatment. This paper investigates the carrier mobility improvement with anneal treatments and summarizes the mobility measurement methods of the a-Si:H and poly-Si film. Various techniques were investigated for the mobility determination such as Hall mobility, HS, TOF, SCLC, TFT, and TCO method. We learned that TFT and TCO method are suitable for the mobility determination of a-Si:H and poly-Si film. The measured mobility was improved by $2{\sim}3$ orders after high temperature anneal above $700^{\circ}C$ and grain boundary passivation using an RF plasma rehydrogenation.

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Mobility-Sensitive Multicast Protocol in NEMO

  • Li, Long-Sheng;Chi, Hung-I;Xie, Kai-Chung;Chan, Din-Yuan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.6
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    • pp.1994-2017
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    • 2022
  • In view of the past, the mobility of the multicast source in the mobility networks is seldom discussed in the traditional multicast protocols. It is a heavy cost for the traditional multicast protocols to reconstruct the multicast tree in the Network Mobility (NEMO) environment. This article proposes an alternative multicast protocol, referred to as Mobility-Sensitive Multicast protocol (MSM), for the NEMO environment. The MSM can be considered as an alternative version of the Multicast Listener Discovery (MLD) protocol to maintain the multicast tree in the NEMO. There are two obvious contributions for the MSM. Reconstruct mechanism could rebuild the multicast tree for the mobility of the multicast source. Multi-group suppression mechanism reduce the multicast tree maintaining cost for the mobility of the multicast members. Through the performance evaluations and analyses, the MSM has less cost to maintain the multicast tree than the traditional multicast protocols, especially for a large numbers of multicast groups. Moreover, the MSM allows the mobility of the multicast source to reconstruct the multicast tree easily.

Control of Weighted Mobility Ratio to Enhance the Performance of Bi-Te-based Thermoelectric Materials (Bi-Te계 열전소재 성능 증대를 위한 Weighted Mobility Ratio 제어)

  • Kim, Min Young;Kim, Hyun-Sik;Lee, Kyu Hyoung
    • Journal of the Microelectronics and Packaging Society
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    • v.28 no.4
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    • pp.103-107
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    • 2021
  • Temperature dependences of electronic and thermal transport properties of narrow band gap thermoelectric materials are dependent on the transport behavior of minority carriers as well as majority carriers. Thus, weighted mobility ratio, which is defined the ratio of weighted mobility for majority carriers to that for minority carriers, must be one of the important parameters to enhance the performance of thermoelectric materials. Herein, we provided a practical guide for the development of high-performance Bi-Te-based thermoelectric materials based on the weighted mobility ratio control by considering theoretical backgrounds related to the electronic transport phenomena in semiconductors.

The Nexus Between Social Mobility and Regional Disparity: Empirical Evidence from India

  • SINGH, Anuradha;MUNIYOOR, Krishna
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.1
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    • pp.229-240
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    • 2022
  • This article examines the link between regional disparity and social mobility in India. There has been a steady rise in economic inequality in India. The rapid economic growth coupled with a rise in income inequality is a serious concern in India. While the emphasis is on inclusive growth, it appears difficult to tackle the problem without looking at the intricacies of the problem. The Social Mobility Index is an important tool that focuses on bringing long-term equality by identifying priority policy areas in the country. We used a multivariate statistical approach to construct a social mobility index at the regional level by considering several social and economic variables. Our findings show that while the Union Territory of Delhi ranks first in the social mobility index, Chhattisgarh has the least social mobility. From a policy perspective, a comprehensive examination of the determinants of the social mobility index shows that health, education access, and quality, and equity of education are of great importance in improving social mobility. Considering India's potential economic growth resulting from its 'demographic dividend' and improved access, markets, and technology, increasing social mobility through facilitating equal opportunities in society is key to achieving inclusive growth.

Temperature Dependence of Electron Mobility in Uniaxial Strained nMOSFETs

  • Sun, Wookyung;Shin, Hyungsoon
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.14 no.2
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    • pp.146-152
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    • 2014
  • The temperature dependence of strain-enhanced electron mobility in nMOSFETs is investigated by using a self-consistent Schr$\ddot{o}$dinger-Poisson solver. The calculated results suggest that vertical compressive stress is more efficient to maintain the strain-enhanced electron mobility than longitudinal tensile stress in high temperature condition.

Development of a conceptual framework of Residential Mobility through multi-disciplinary Approach (주거학을 중심으로한 학문적 체계)

  • BokChaYoon
    • Journal of the Korean housing association
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    • v.3 no.2
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    • pp.33-41
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    • 1992
  • The purpose of this study was (1) to analyze concept and types of residential mobility (2) to compare of the residential mobility in the fields of different disciplives, and (3) to develop a conceptual framework of residential mobility on the ecosystem approach comparisons of residential mobility concepts in many discipines. The major findings were each disciple played an important role to develop the concept of residential mobility with some limitations. A conceptual frame-work was developed on the basis of these findings.

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Study on the Mechanical Networks of Linear Mechanical Vibrating Systems (선형기계진동계통의 전기회로망적 고찰)

  • 이상배
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.12 no.4
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    • pp.41-45
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    • 1975
  • 기계계와 전기계 사이의 두 analogy로부터 mobility 회로와 impedamice회로를 얻었다. 이 두 기계기로에서 Ipedance와 nobility관계를 회로망리론을 근거로 비교 검토 하였고 이로부터 mobility 회로가 더 자연스럽고 기본적인 기계회로임을 구명하였다. 또한 impedance측정이 관찰점과 수에 따라서 가변성인데 비하여 mobility 측정은 불변성임을 보였다. Two mechanical networks, mobility network, and impedance network, are proposed md the relations between a mechanical system n4 their two mechanical networks are examined briefly. The mobility network is founed to be more natural of two networks. This paper also shows the invariant property of mobility elements in the measurement procedure.

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A Scalable Multicasting with Group Mobility Support in Mobile Ad Hoc Networks

  • Kim, Kap-Dong;Lee, Kwang-Il;Park, Jun-Hee;Kim, Sang-Ha
    • Journal of Information Processing Systems
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    • v.3 no.1
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    • pp.1-7
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    • 2007
  • In mobile ad hoc networks, an application scenario requires mostly collaborative mobility behavior. The key problem of those applications is scalability with regard to the number of multicast members as well as the number of the multicast group. To enhance scalability with group mobility, we have proposed a multicast protocol based on a new framework for hierarchical multicasting that is suitable for the group mobility model in MANET. The key design goal of this protocol is to solve the problem of reflecting the node's mobility in the overlay multicast tree, the efficient data delivery within the sub-group with group mobility support, and the scalability problem for the large multicast group size. The results obtained through simulations show that our approach supports scalability and efficient data transmission utilizing the characteristic of group mobility.

Comparative Analysis of the Use of a Pedestrian Facility for Non-Mobility Handicapped and Mobility Handicapped in Urban Rail Station (일반인과 교통약자의 도시철도 역사의 보행시설 이용에 관한 비교분석)

  • HwangBo, Hyun;Jung, Hun-Young;Kim, Hyun-Woong
    • Proceedings of the KSR Conference
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    • 2011.05a
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    • pp.757-762
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    • 2011
  • As our society is becoming an aging society, there is an increasing number of the elderly. Recently, mobility handicapped like the elderly and the disable take part in many social activities. It is required public transportation systems for them. Already, the traffic policy for mobility handicapped including pregnant woman and child, has been established in many cities. Particularly, the convenience of mobility for the handicapped in the urban rail stations is depend on a pedestrian facilities like escalators and elevators. The pedestrian facilities have been built in urban rail stations without rules for mobility handicapped. To make the more convenient and more safe stations, the more study about mobility handicapped and non-mobility handicapped is needed. This paper preferentially discusses the pedestrian facilities with other convenience facilities in urban rail stations. This paper explains also their preference, relative satisfaction and importance for the convenience facilities including the a pedestrian facilities in urban rail stations and makes clear the difference between both groups.

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