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یک الگوریتم ژنتیک برای حل مساله گراف چند مرحله ای |
| عنوان انگلیسی مقاله: | A Genetic Algorithm for Solving Multistage Graph Problem |
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روش های بهینه سازی گزینش شده برای مدیریت مالی تحت شرایط غیر قطعی |
| عنوان انگلیسی مقاله: |
Selected parallel optimization methods for financial management under uncertainty |
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عنوان فارسی مقاله:
طراحی آنتن برای ورودی محیطی شبکه های حسگر متعدد عظیم
عنوان انگلیسی مقاله:
Antenna design for a massive multiple input environmental sensor network
سال انتشار : 2016
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مقدمه انگلیسی مقاله:
1. Introduction
HOSTED BYContents lists available atScienceDirectDigital Communications and Networksjournal homepage:www.elsevier.com/locate/dcanAntenna design for a massive multiple input environmental sensornetwork☆J. Craig Prather⁎,1, Michael Bolt, Haley Harrell, John Manobianco2, Mark L. AdamsDepartment of Electrical and Computer Engineering, 200 Broun Hall, Auburn University, AL 36849, United StatesARTICLE INFOKeywords:AntennaEnvironmental sensingRemote sensingMassive multiple input networkABSTRACTThis article describes the design and simulation of a pair of antennas on a small PCB with minimal coupling fora massive multiple input sensor network. The two antennas are planar inverted-F antennas (PIFA) that are fedwith microstrip feed lines. The critical design factors are minimizing mass while creating ISM band and GPS L1band antennas and developing data transmission schemes for maximum usage of all communication channels.The designed board is a 60 mm diameter, 0.6 mm thick circular FR4 board that weighs approximately 5 g.1. IntroductionCurrently, atmospheric researchers rely heavily on remote sensingtechnologies such as satellites to predict the weather; however, there isa tremendous need for additional in-situ measurements to improveweather models and create more accurate forecasts. Current in-situmeasurements for hurricane reconnaissance primarily rely on devicesknown as dropsondes. The dropsondes have a terminal velocity of11 m/s at sea level, and approximately 21 m/s at a 12 km altitude[1].For more quiescent conditions, weather balloons carrying radiosondes[2] are launched around the globe every day to measure the propertiesof the atmosphere. This article showcases the antenna design andapplication of a novel type of atmospheric sensor which our group isdeveloping as an alternative to these devices.The devices will be part of a new atmospheric monitoring systemknown as GlobalSense[3]. The system features an ensemble ofdisposable airborne drifters, called environmental motes or eMotes,as can be seen inFig. 1, that will be carried by wind currents much likenaturally occurring dandelion or maple seeds. The GlobalSense systeminnovation is based on the continuing trend for ubiquitous sensing[4,5],also known as the Internet-of-Things[6,7], where extremelylarge numbers of disposable, low-cost electronic devices measurevarious parameters and communicate that data in different formatsand frequencies for various applications.Once deployed from balloons or aircraft, eMotes will transmit lowpower signals in one of the industrial, scientific, and medical (ISM)radio bands to avoid expensive licensing requirements. Thefixed ormobile receiver platforms will contain hardware and software to gatherand process sensor and other data from multiple eMotes within rangeand store or retransmit the information to other locations. TheGlobalSense system has been designed to support up to 50,000eMotes operating simultaneously.The GlobalSense system could benefit a wide range of applicationswith sensitivity to atmospheric conditions including but certainly notlimited to energy, transportation, agriculture, construction, insurance,and tourism. The initial focus is on improving weather analysis andforecasting by greatly expanding the time and space density of criticalweather parameters such as temperature, pressure, wind velocity, andhumidity throughout as much of the relevant atmospheric volume aspossible.With the appropriate chemical sensors integrated on eMote plat-forms, the GlobalSense system could monitor air quality and green-house gases such as carbon dioxide and methane for global climatechange initiatives[8,9]. Even broader applications involve measuringparameters of interest for surveillance, reconnaissance, and relatedapplications. The modular and interoperable system design makes itrelatively straightforward to integrate other sensors that have theappropriate specifications.The current prototype eMotes have a mass around 7 g with aterminal velocity<5m/swhich provides greater dwell time in theatmosphere than typical environmental sensors. Thefinal design goalsare an eMote mass≤1 gand a terminal velocity on the order of 1 m/s
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کلمات کلیدی:
Target detection in cluster based WSN with massive MIMO systems ...ieeexplore.ieee.org/document/7792309/?section=abstractAbstract: Neyman-Pearson detection method is presented for a cluster-based wireless sensor network (WSN) massive multiple-input multiple-output (MIMO) ...Machine Learning in Wireless Sensor Networks: Algorithms ... - arXivhttps://arxiv.org/pdf/1405.4463by MA Alsheikh - 2014 - Cited by 79 - Related articlesMar 19, 2015 - Index Terms—Wireless sensor networks, machine learning, ... of multiple autonomous, tiny, low cost and low power sensor nodes. These nodes gather data about their environment .... the learned relation between the input, output and system .... is for big data (high-dimensional and complex data set) tuning.MIMO - Wikipediahttps://en.wikipedia.org/wiki/MIMOIn radio, multiple-input and multiple-output, or MIMO is a method for multiplying the capacity of .... While full multi-user MIMO (or network MIMO) can have a higher potential, practically, the research on (partial) ... In a rich scattering environment, the full advantages of the massive MIMO system can be exploited using simple ...Fun with Algorithms: 5th International Conference, FUN 2010, Ischia, ...https://books.google.com/books?isbn=3642131220Paolo Boldi, Luisa Gargano - 2010 - ComputersEven though we are using sensors in an ever-increasing number of ways, we have ... evident by the massive success of mobile platforms, like Sony's PSP, or even devices like ... and sensory input, all provided by the use of sensor networking techniques. Players interact with each other and their surrounding environment by ...Disaster Nursing and Emergency Preparedness: for Chemical, ...https://books.google.com/books?isbn=0826108652Tener Goodwin Veenema, PhD, MPH, MS, CPNP, FAAN - 2012 - MedicalInfrared Detectors and Thermal Cameras: A form of passive remote sensing that can be ... to single molecules), three-dimensional imaging, and temperature sensing. ... seen massive growth in the number and diversity of prepositioned, mobile, ... of multiple heterogeneous sensor inputs permits cross-validation (minimizing ...Topology Control in Emerging Sensor Networks - MDPIwww.mdpi.com/journal/sensors/special_issues/Emerging_Sensor_NetworksInterests: ad hoc and sensor networks ; Internet-of-Things (M2M) ; Security and ... grid; energy harvesting; social networks; big data; green computing/networking; ... the environment requires empowering conventional sensor networks with other ...... Multi-Input Multi-Output (MIMO) can improve wireless network performance.Computational Science - ICCS 2003. Part 4.: International Conference ...https://books.google.com/books?isbn=3540401970Peter Sloot - 2003 - Computers... of supersonic platform and b) fire-material-environment interaction, monitoring, assessment and ... Prior time (operator controllable) data driveness where massive data from automated ... from a distributed sensor network that can be monitored from multiple points of entry. ... Based on input from the previous two items, the.Searches related to massive multiple input environmental sensor networkieee access impact factorieee xploresci hubscholar
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عنوان فارسی مقاله:
توزیع محتوای هاپ توسط هاپ با برنامه نویسی شبکه در شبکه بی سیم چند جهشی
عنوان انگلیسی مقاله:
Hop-by-hop Content Distribution with Network Coding in Multihop Wireless Networks
سال انتشار : 2017
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مقدمه انگلیسی مقاله:
1. Introduction
The predominant use of today's Internet is content access anddistribution. Multimedia content traffic is growing at an exponentialrate. This trend is expected to continue in the foreseeablefuture. For example, it is forecasted by Cisco [1] that globalmobile data traffic will increase nearly tenfold between 2014 and2019. Recently, there is renewed research interest in supportingmulticast distribution to deliver various services such as live eventvideo streaming, social content pushing, file sharing, softwareupgrades, mobile TV, as well as other applications for whichmultiple users concurrently consume the same content [2]. Thedemand for these applications is becoming increasingly common,and multicast is much more efficient in delivering them thanunicast by sharing network resources. The Third GenerationPartnership Project (3GPP) recently defined the Evolved MultimediaBroadcast/Multicast Service (eMBMS) standard [3] to supportstreaming and downloading applications. Several operatorshave started field trials for eMBMS services.These multicast applications have strict quality of service (QoS)requirements. Many of them require 100% reliability with highthroughput. Any packet loss may cause severe quality degradation,and users always desire to get content as quickly as possible. It ischallenging to achieve reliable and high-throughput multicast,especially in multihop wireless mesh networks (WMNs) due tointerference, channel fading, and limited bandwidth. Furthermore,a unique issue in multicast is bandwidth heterogeneity amongstmulticast receivers. The receivers with poor network connectivityor a low-throughput path from the source may greatly degrade theperformance of receivers with good network connectivity as thereliability requirements of the worst receiver have to be met.Traditional reliable multicast protocols, including eMBMS, areclient–server based, in which intermediate routers or forwardingnodes simply duplicate and forward packets. These protocolsemploy end-to-end forward error correction (FEC), automatic repeat request (ARQ) or hybrid FEC-ARQ techniques [4–7] at theapplication layer of the clients and servers to achieve multicastreliability. However, their performance is limited by the multicastreceivers with the worst path from the source.Network coding (NC) is an innovative technique to improvereliability and throughput in WMNs. The basic idea of NC is toallow intermediate forwarding nodes (FNs) to encode data packets,instead of simply replicating and forwarding packets, and thustake advantage of the wireless broadcast medium to reduce thenumber of required transmissions for delivery of the data [8,9].Especially, intra-flow random linear network coding [10,11] hasattracted interest due to its low control overhead and high effi-ciency along with implementation simplicity, in which a FN randomlygenerates linear combinations of received packets belongingto a data flow over some fields, and forwards the codedpackets. Random mixing at each FN ensures that if a group of FNshear the same packet transmission, with high probability, thecoded packets generated and forwarded by the different FNs willbe linearly independent, removing duplicate packet transmissionsover shared wireless medium. A node can not only receive thepackets from its direct parent node but also overhear the codedpackets of the same data flow transmitted by other neighbors.Intra-flow random NC thus makes opportunistic forwarding andoverhearing more effective in WMNs so as to achieve significantperformance gains compared to non-coding schemes.However, the use of NC introduces new challenges in designinga practical multicast protocol. First, a FN does not need to encodeand then forward a coded packet whenever it receives a packetfrom its upstream node because its downstream node may overhearpackets from other neighbors. Consider a simple example inwhich a source S multicasts two packets, P1 and P2, to two destinationreceivers, D1 and D2 through a FN, F, as shown in Fig. 1. Stransmits two coded packets, P P 1 2 + and P P 1 2 + 2 in sequence,which can be represented by the corresponding coding vectors (1,1) and (1, 2). Assume that F receives both packets, and D1 and D2overhear coded packets (1, 1) and (1, 2), respectively. In fact, F onlyneeds to generate one coded packet from the received two packets,e.g. 3P P 1 2 + 4 , and forward it. D1 and D2 can decode and obtainthe original packets P1 and P2 after they receive coded packet3P P 1 2 + 4 from F. However, F may not know that D1 and D2 haveoverheard a packet from S as it has limited knowledge of the receptionstatus of D1 and D2 with regard to the two packets sent byS. It is nontrivial for F to decide the number of coded packets itshould send and the time when to stop sending. Therefore, onechallenge in the NC protocol design is to address how many codedpackets each FN should send in order to guarantee all the multicastdestination receivers obtain enough packets to decode theoriginal data. In addition, how should the bandwidth heterogeneityof the paths from the source to the different destinationreceivers be handled by the multicast protocol? To deliver thebenefits offered by intra-flow NC, a practical protocol needs toaddress the above challenges.Although various NC schemes have been studied under differentnetwork settings, practical protocol design for reliable multicastwith NC in WMNs has received relatively little attention.MORE [11] and Pacifier [12] are the two state-of-the-art intra-flowNC-based multicast protocols with different selections of forwardingnode topologies. Both of them employ a transmissioncredit (TX_Credit) approach, in which the source computes andassigns a TX_Credit to each FN based on the periodical packet lossrate measurements of the links on the network. The sourcetransmits the coded packets from a data chunk, and the TX_Creditvalues are carried in the packet header that indicates the numberof coded packets a FN should transmit upon receiving the packetfrom its upstream node. An intermediate FN simply determineswhether and how many coded packets transmit to its downstreamnodes according to the TX_Credit assigned to it in the receivedpacket. The successful data delivery is verified through end-to-endacknowledgements (ACKs). The source continues sending codedpackets until it receives the ACKs from all its multicast destinationreceivers. However, with this approach, the FNs may transmit thepackets much more than necessary, significantly wasting wirelessresources, because it is very difficult to obtain the accurate estimationof the TX_Credit for each FN in dynamic wireless environments,and the end-to-end ACKs may be delayed or lost.In this paper, we take a different approach, and propose a novelintra-flow NC-based hop-by-hop reliable multicast protocol,termed HopCaster, to achieve high-throughput over WMNs andsolve the bandwidth heterogeneity issue of multicast receivers. Incontrast to the existing NC-based multicast protocols, HopCastercompletely eliminates the need for estimating the TX_Credit, aswell as simplifying multicast management and congestion control.Moreover, a cross-layer rate adaptation mechanism is proposed,which maximizes the multicast throughput by dynamically adjustingthe wireless transmission rate to the changes in the receiverpopulation and wireless channels during multicast of acoded data chunk. The evaluation results show that HopCasterachieves significant throughput gains compared to the state-ofthe-artNC-based multicast protocols.The remainder of this paper is organized as follows. Relatedwork is reviewed in Section 2. In Section 3, we present the HopCasterprotocol design. Section 4 describes the cross-layer rateadaptation mechanism. In Section 5 we show the evaluation resultsand performance comparison of HopCaster with the existingNC-based multicast protocol. The paper is concluded in Section 6.
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کلمات کلیدی:
[PDF]A Wireless Medium Access Control Using Network Coding for Multi ...https://www.eecs.harvard.edu/~htk/.../2008-milcom-cheng-kung-lin-su-vlah.pdfby CM Cheng - Cited by 18 - Related articlesRainbow: A Wireless Medium Access Control Using Network Coding for Multi-hop Content ... ticularly important to data broadcast in wireless distributed computing where ... tribution protocol for multi-hop wireless ad-hoc networks. The protocol ...[PDF]Network Coding for Multi- Hop Wireless Networks - IRMA Internationalwww.irma-international.org/viewtitle/36549/Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited. ... Network Coding for Multi-Hop Wireless Networks.[PDF]Application of network coding in wireless networks - Halhttps://hal.archives-ouvertes.fr/tel-01022166/documentRelated articlesJul 10, 2014 - 2.5.2 Distributed Coding-Aware Routing (DCAR) . . . . . . . . . . 23 ... 2.7.1.1 Multi-hop traffic flows in wireless networks . . . . . . 33. 2.7.1.2 ...Hop-by-hop Content Distribution with Network Coding in Multihop ...https://www.researchgate.net/.../308004170_Hop-by-hop_Content_Distribution_with_N...Download academic paper: Hop-by-hop Content Distribution with Network Coding in Multihop Wireless Networks on ResearchGate.Multiantenna Analog Network Coding for Multihop Wireless Networkshttps://www.hindawi.com/journals/ijdmb/2010/368562/by R Annavajjala - 2010 - Cited by 12 - Related articlesOct 26, 2009 - Multiantenna Analog Network Coding for Multihop Wireless Networks ... which permits unrestricted use, distribution, and reproduction in any ...[PDF]Network Coding for Efficient Wireless Unicast - MITwww.rle.mit.edu/ncrc/wp-content/uploads/.../2006_network_coding_efficient.pdfby DS Lun - Cited by 124 - Related articlesunicast connections over wireless packet networks. We show how network coding, combined with distributed flow optimiza- tion, gives a practicable ..... ments for unicast in multi-hop wireless networks, and we have suggested practicable ...Network Coding for Severe Packet Reordering in Multihop Wireless ...dsn.sagepub.com/content/11/8/379108.fullNetwork coding is known to be effective in overcoming packet losses and packet reordering in multihop wireless networks. Despite the benefits, network coding ...
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آیا ذخیره ویدئو باعث بهبود انرژی در شبکه های نوری هسته آینده شود؟
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?Will video caching remain energy efficient in future core optical networks
سال انتشار : 2017
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پروتکل ارتباطی مطمئن، تاخیر محدود شده و کمتر پیچیده برای شبکه های ادهاک سریع چند خوشه ای
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A reliable, delay bounded and less complex communication protocol for multicluster FANETs
سال انتشار : 2017
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ارتباط صنعت 5.0 و مفاهیم بیونیک و زیست شناسی مصنوعی
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Industry 5.0—The Relevance and Implications of Bionics and Synthetic Biology
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Big Data Research in Italy: A Perspective
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شهر هوشمند به عنوان سیستم های اجتماعی سایبری فیزیکی
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Smart Cities as Cyber-Physical Social Systems
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