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1.
Shafiq Maryam Ashraf Humaira Ullah Ata Tahira Shireen 《Mobile Networks and Applications》2020,25(3):882-895
Mobile Networks and Applications - In wireless sensor networks (WSN), routing is quite challenging area of research where packets are forwarded through multiple nodes to the base station. The... 相似文献
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LIU Zhi-qing~ WANG Peng~ .School of Software Engineering Beijing University of Posts Telecommunications Beijing P.R. China .University Information Technology Services Indiana University Bloomington IN . 《中国邮电高校学报(英文版)》2004,11(3)
1 Introduction Manycrucialapplicationssuchasteleconferencing ,distributedcomputingarebecomingfeasiblewithemerging high performancenetworkservices .ThesenetworkservicessuchasFDDI ,ATMandHIPPIpro videhighbandwidthandlowlatency .Forexample ,FDDIcouldoperateat 10 0Mb/s;Sonet/ATMOC 12couldoperateat 6 2 2Mb/s .Somehigh speedLANssuchasMyrinetandgigabit ethernet ,andSonet/ATMOC 4 8networkbackbonescanoperateat 1Gb/sandabove . However,thesehigh performancenetworkservicesareyettobefully… 相似文献
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A Web‐based survey (N = 306) examined if Twitter use enhances individuals' news knowledge, and if so, how such effects might vary depending on their need for orientation (NFO) and the type of news (hard vs. soft). The duration of Twitter use positively predicted hard news knowledge, but only for those higher in NFO. In contrast, daily Twitter use had negative influence on high NFOs' soft news knowledge, with no corresponding effect for lows. Although high NFOs were more likely to use Twitter for information‐seeking than their less surveillance‐driven counterparts, such motivation did not facilitate knowledge gain. Systematic processing of public affairs information and selective avoidance were discussed as potential explanations for differential knowledge gain by high and low NFOs. 相似文献
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Vector quantization (VQ) is an efficient technique for data compression and has been successfully used in various applications.
The methods most commonly used to generate a codebook are the Linde, Buzo, Gray (LBG) algorithm, fuzzy vector quantization
(FVQ) algorithm, Kekre‘s Fast Codebook Generation (KFCG) algorithm, discrete cosine transform based (DCT-based) codebook generation
method, and k-principle component analysis (K-PCA) algorithm. However, if the separation boundaries in codebook generation
are nonlinear, their performance can degrade fast. In this paper, we present a kernel fuzzy learning (KFL) algorithm, which
takes advantages of the distance kernel trick and the gradient-based fuzzy clustering method, to create a codebook automatically.
Experiments with real data show that the proposed algorithm is more efficient in its performance compared to that of the LBG,
FVQ, KFCG, and DCT-based method, and to the K-PCA algorithm. 相似文献
5.
《Mechatronics》2014,24(2):168-176
In this paper, we propose a human–robot cooperation controller for the motion of the upper limb exoskeleton. The system permits three degrees of freedom using an electrical actuator that is mainly controlled by force sensor signals. These signals are used to generate the torque required to drive the exoskeleton. However, singularities exist when the force signals in the Cartesian coordinate system are transformed into torques in the joint coordinate system. Therefore, we apply the damped least squares method. When handling a load, torque compensation is required about its mass. Therefore, we installed a force sensor at the point of the robot’s end-effector. It measures the forces between the exoskeleton and the load. Then, these forces are used to compensate within a static model for handling loads. We performed control stability and load handling experiments to verify the effectiveness of the controller. Via these, we confirmed the effectiveness of the proposed controller. 相似文献
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Despite the seemingly obvious importance of a link between notions of place and the provision of context in location-based services (LBS), truly place-based LBS remain rare. Place is attractive as a concept for designing services as it focuses on ways in which people, rather than machines, represent and talk about places. We review papers which have extracted place-relevant information from a variety of sources, examining their rationales, the data sources used, the characteristics of the data under study and the ways in which place is represented. Although the data sources used are subject to a wide range of biases, we find that existing methods and data sources are capable of extracting a wide range of place-related information. We suggest categories of LBS which could profit from such information, for example, by using place-related natural language (e.g. vernacular placenames) in tracking and routing services and moving the focus from geometry to place semantics in location-based retrieval. A key future challenge will be to integrate data derived from multiple sources if we are to advance from individual case studies focusing on a single aspect of place to services which can deal with multiple aspects of place. 相似文献
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Moore's (1965) law, which predicts that the number of transistors on an integrated circuit doubles every 18-24 months, has held remarkably well over three decades of semiconductor device production. Using historical data, a similar prediction is made for modem speeds, and in particular for the speed at which data can be transmitted over twisted wire pairs, where it is found that modem data rates have historically doubled every 1.9 years. This result suggests that rapid increases in bandwidth delivered to subscribers over the coming decades will have profound societal and economic effects, just as the development of the integrated circuit and the microprocessor have had. Nevertheless, the regulated aspect of telecommunications may limit the growth of bandwidth and the deployment of high-speed modems which deliver services over existing twisted wire pairs. The cable environment, which from a data transmission perspective is, generally speaking, less regulated, may allow for deployment of modems which support rates in excess of what is predicted by our Moore's law analogy. In this article we examine Moore's law as applied to modem technology, and how regulation may affect the deployment of broadband services 相似文献
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《Multimedia, IEEE》1999,6(2):76-79
The paper discusses WebDAV (Web Distributed Authoring and Versioning) which provides the mechanism that will allow authoring of documents over the Internet. A series of extensions to hypertext transfer protocol (http), it allows not only the retrieval of Web documents, but the in-place editing of them as well. Could WebDAV represent the most significant change to authoring since the advent of the printing press? Can it really change the way we create and maintain Web sites? 相似文献
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In this paper, we study optimal nonlinear pricing policy design for a monopolistic network service provider in the face of a large population of users of different types described by a given probability distribution. In an earlier work (Shen and Ba?ar in IEEE J. Sel. Areas Commun. 25(6):1216?C1223, 2007), we had considered games with symmetric information, in the sense that either users?? true types are public information available to all parties, or each user??s true type is private information known only to that user. In this paper, we study the intermediate case with information asymmetry; that is, users?? true types are shared information among the users themselves, but are not disclosed to the service provider. The problem can be formulated as an incentive-design problem, for which an ??-team optimal incentive (pricing) policy has been obtained, which almost achieves Pareto optimality for the service provider. A comparative study between games with information symmetry and asymmetry are conducted as well to evaluate the service provider??s game preferences. 相似文献
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Antonio Iera Antonella Molinaro Stefano Yuri Paratore Giuseppe Ruggeri Antonella Zurzolo 《Ad hoc Networks》2011,9(8):1414-1429
This paper aims at answering the question whether it is practical to build a mesh-phone or not. A mesh-phone is a smartphone acting as a mesh router, i.e. either actively participating in the process of packet forwarding towards a mesh gateway, or acting itself as a gateway toward the Internet. Technical aspects of the mesh-phone implementation, such as design constraints and implementation details, are addressed. The technical feasibility is validated by describing the implementation of a prototype of the mesh-enabled phone over the OpenmokoTM open platform. Besides technical feasibility also convenience of the addressed solution is analyzed in terms of the consumed power, and some “energy-saving” related enhancements are suggested to be applied to future user’s devices. 相似文献
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Artists, along with technologists, have historically stood at the forefront of multimedia-blurring boundaries and crossing borders, penetrating the looking glass, pushing the envelope with the R&D of their creative explorations using new technologies. In the process, they redefine the very notions of both art and artist. These artists work in multiple disciplines, across platforms, creating new forms from hybrid combinations, defying the labels of definition, and inventing new languages. In most cases, the art experience-no longer passive-requires some sort of interactive participation 相似文献
14.
Asiatici Mikhail Maiorano Damian Ienne Paolo 《Journal of Signal Processing Systems》2021,93(12):1405-1417
Journal of Signal Processing Systems - String sorting is a fundamental kernel of string matching and database index construction; yet, it has not been studied as extensively as fixed-length keys... 相似文献
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Providing an efficient and stable communication framework of Vehicular Ad hoc Network (VANET) is an emerging issue. Most of conventional VANET communication schemes only support short range transmission, vehicles need to relay traffic data or frequently switch to different roadside units. Such an ad hoc-based method suffers a high jitter delay and makes it difficult to develop travel and real-time multimedia services, such as traffic information dissemination and fleet management. Fortunately, existing novel wireless technologies, e.g. WiMAX mobile multi-relay (MMR), provide long transmission range and high transmission rate in mobile environments. This study presents a Safety/Vehicular Information Delivery (SVID) framework, an application-layer VANET communication protocol. A power-abundant, large size vehicle, called SIP-based relay vehicle (SRV), e.g. long distance transportation bus, plays as a relay station (RS) providing the connectivity to other small vehicles around it. To provide VANET services in SVID, this work adopts a SIP-based mechanism. The proposed scheme can provide more efficient communication than conventional VANET ad hoc mode. Simulation results show that the proposed scheme achieves a low SIP transaction time, jitter delay, frame loss rate while avoiding the broadcast storm problem. 相似文献
16.
Nav Gulati 《International Journal of Network Management》1998,8(4):206-210
• How will Year 2000 technology problems create acquisitions opportunities? • If we are heading towards deflationary times, will the Year 2000 problem further exacerbate the cycle? • What are the technology action items today, so we can be prepared to buy our competitors if the regulators shut them down? • If, due to the Millennium Bug, our targets fail as going concerns, what does it take to plug them into our technology environment? © 1998 John Wiley & Sons, Ltd. 相似文献
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1 IntroductionTheInternethasrecentlybeenexperiencinganexplosivegrowthintheuseofreal timemultimediaservices.Real timemultimedia,asthenameim plies ,hastimingconstraints.Toavoidtheunac ceptabledelayintroducedbyretransmission ,real timemultimediaapplicationsusually preferUDP .However,aconsiderableamountof greedyUDPtrafficwoulddominatemuchnetworkbandwidth .Asaresult,theavailablebandwidthtoTCPconnec tionsisoppressedandtheirperformanceextremelydeteriorates.InorderforbothTCPandUDPses sionstof… 相似文献
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Tsai Ming-Jer Pimmel Russell L. Bromberg Philip A. 《IEEE transactions on bio-medical engineering》1979,(3):140-147
Enforced smoothing techniques for computing V?A/Q? distributions from inert gas retentions were evaluated by recovering distributions from artificial data. The value of the smoothness parameter z was varied with smoothness constraints that minimized the area either under the square of the distribution or under the square of the second derivative of the distribution. The accuracy of the recovered distributions were quantified by the RMS difference between the original and the recovered distributions. Values of z outside of a certain range (typically, 0.01 ?z ?32) produced underflow or overflow interrupts with the IBM 370/165. Since the optimum value of z varied with the smoothness constraint, the form of the distribution, and the level of random error, it is difficult to select a best value of z for all situations. RMS differences were similar to those achieved with the gradient descent method, and some compartments had smiall negative flows Using linear programming, upper bounds were found for the solution space that contains al possible solutions. The non-negativity constraint extremely limits this space, application of a smoothness constraint further reduces this space, and the addition of 3% random error to the retention values expands it. 相似文献
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This paper reviews some basic computer vision techniques and speculates about their possible relevance to the modeling of human visual processes. Special emphasis is given to image segmentation techniques and how they relate to processes of perceptual organization, such as those embodied in the Gestalt "laws." 相似文献