18,349 research outputs found

    Building Programmable Wireless Networks: An Architectural Survey

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    In recent times, there have been a lot of efforts for improving the ossified Internet architecture in a bid to sustain unstinted growth and innovation. A major reason for the perceived architectural ossification is the lack of ability to program the network as a system. This situation has resulted partly from historical decisions in the original Internet design which emphasized decentralized network operations through co-located data and control planes on each network device. The situation for wireless networks is no different resulting in a lot of complexity and a plethora of largely incompatible wireless technologies. The emergence of "programmable wireless networks", that allow greater flexibility, ease of management and configurability, is a step in the right direction to overcome the aforementioned shortcomings of the wireless networks. In this paper, we provide a broad overview of the architectures proposed in literature for building programmable wireless networks focusing primarily on three popular techniques, i.e., software defined networks, cognitive radio networks, and virtualized networks. This survey is a self-contained tutorial on these techniques and its applications. We also discuss the opportunities and challenges in building next-generation programmable wireless networks and identify open research issues and future research directions.Comment: 19 page

    AplikĂĄcia kognitivnĂ©ho modelu vizuĂĄlnej pozornosti v automatizovanej montĂĄĆŸi

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    ZĂĄsobovacie zariadenia a podsystĂ©my v ĆĄtruktĂșrach montĂĄĆŸnych systĂ©mov majĂș vĂœznamnĂ© postavenie. TechnickĂș zloĆŸitosĆ„ klasickĂœch zĂĄsobovacĂ­ch zariadenĂ­ a podsystĂ©mov je moĆŸnĂ© eliminovaĆ„ pruĆŸnĂœmi programovateÄŸnĂœmi automatizovanĂœmi zariadeniami. InformĂĄcie o spomĂ­nanom objekte zabezpečovanĂ© senzorovĂœmi modulmi sa spracovĂĄvajĂș v riadiacom systĂ©me zariadenia resp. na vyĆĄĆĄej Ășrovni riadenia montĂĄĆŸneho systĂ©mu. SpracovanĂ© informĂĄcie sĂș distribuovanĂ© ako riadiace informĂĄcie vĂœkonnĂœm jednotkĂĄm a prvkom, ktorĂ© vykonĂĄvajĂș prĂ­sluĆĄnĂ© funkcie. Riadiace systĂ©my programovateÄŸnĂœch zĂĄsobovacĂ­ch zariadenĂ­ a podsystĂ©mov plnia viacerĂ© funkcie napr. spracovanie informĂĄciĂ­ od senzorovĂœch jednotiek a modulov, sprĂĄvne vyhodnotenie polohy sĂșčiastky a určenie postupu činnosti vĂœkonnĂœch jednotiek a prvkov, distribĂșcia vĂœkonnĂœch inĆĄtrukciĂ­ pohonovĂœm jednotkĂĄm, atď. ProgramovĂ© vybavenie zaloĆŸenĂ© na vyuĆŸĂ­vanĂ­ kognitĂ­vneho modelu vizuĂĄlnej pozornosti charakterizuje novĂœ prĂ­stup k rieĆĄeniu uvĂĄdzanĂœch problĂ©mov. Pri vizuĂĄlnom vnĂ­mĂĄnĂ­ scĂ©ny obsahujĂșcej rĂŽzne objekty a pre potrebu interakcie s určitĂœm cieÄŸovĂœm objektom nachĂĄdzajĂșcim sa v tejto scĂ©ne je nutnĂ© aby systĂ©m upriamil svoju pozornosĆ„ na tento (cieÄŸovĂœ) objekt. Tento mechanizmus je jednĂœm z principiĂĄlnych prvkov videnia a podobne ako mnoho biologicky motivovanĂœch systĂ©mov je veÄŸmi vĂœhodne vyuĆŸiteÄŸnĂœ v praxi. NavrhovanĂœ model je implementĂĄciou mechanizmu vizuĂĄlnej pozornosti vo vytvorenom počítačom simulovanom prostredĂ­.Logistic devices and sub - systems in the structures of assembly systems have significant position. Technical complexity of classical devices and sub - systems can be decreased by using of flexible programmable automated devices. Information's about objects provided by sensor modules are handled in processing system of the device, respective on the higher level of the assembly system. Executed information is distributed like processing information to executive units and elements. Control systems of programmable supply devices and sub - systems take handle of many functions, for example: processing information from sensor devices and modules, right calculating of the bearing of the component, distributing of executive instructions to actuating units, and many others. Software accessories based on the using of cognitive model of visual attention featured a new way of solving former problems. By visual reception the scenes contains miscellaneous objects and for the demand of the interaction with the target object is necessary that the system is need to be focused to this object. This mechanism is one of the pricipally elements of vision, and like many biologically motivated systems is very useful in practice. Designed model is an implementation of the mechanism of visual attention in the computer created simulation environment

    Management and Service-aware Networking Architectures (MANA) for Future Internet Position Paper: System Functions, Capabilities and Requirements

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    Future Internet (FI) research and development threads have recently been gaining momentum all over the world and as such the international race to create a new generation Internet is in full swing: GENI, Asia Future Internet, Future Internet Forum Korea, European Union Future Internet Assembly (FIA). This is a position paper identifying the research orientation with a time horizon of 10 years, together with the key challenges for the capabilities in the Management and Service-aware Networking Architectures (MANA) part of the Future Internet (FI) allowing for parallel and federated Internet(s)

    Programmable photonics : an opportunity for an accessible large-volume PIC ecosystem

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    We look at the opportunities presented by the new concepts of generic programmable photonic integrated circuits (PIC) to deploy photonics on a larger scale. Programmable PICs consist of waveguide meshes of tunable couplers and phase shifters that can be reconfigured in software to define diverse functions and arbitrary connectivity between the input and output ports. Off-the-shelf programmable PICs can dramatically shorten the development time and deployment costs of new photonic products, as they bypass the design-fabrication cycle of a custom PIC. These chips, which actually consist of an entire technology stack of photonics, electronics packaging and software, can potentially be manufactured cheaper and in larger volumes than application-specific PICs. We look into the technology requirements of these generic programmable PICs and discuss the economy of scale. Finally, we make a qualitative analysis of the possible application spaces where generic programmable PICs can play an enabling role, especially to companies who do not have an in-depth background in PIC technology

    New software tool to characterize photovoltaic modules from commercial equipment

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    A software platform has been developed in order to unify the different measurements obtained from different manufacturers in the photovoltaic system laboratory of the University of Malaga, Spain. These measurements include the current-voltage curve of PV modules and several meteorological parameters such as global and direct irradiance, temperature and spectral distribution of solar irradiance. The measurements are performed in an automated way by a stand-alone application that is able to communicate with a pair of multimeters and a bipolar power supply that are controlled in order to obtain the current–voltage pairs. In addition, several magnitudes, that can be configured by the user, such as irradiance, module temperature or wind speed, are incorporated to register the conditions of each measurement. Moreover, it is possible to attach to each curve the spectral distribution of the solar radiation at each moment. Independently of the source of the information, all these measurements are stored in a uniform relational database. These data can be accessed through a public web site that can generate several graphics from the data.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Junta de Andalucía. Proyecto de Excelencia P11-RNM-711

    Non-classical computing: feasible versus infeasible

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    Physics sets certain limits on what is and is not computable. These limits are very far from having been reached by current technologies. Whilst proposals for hypercomputation are almost certainly infeasible, there are a number of non classical approaches that do hold considerable promise. There are a range of possible architectures that could be implemented on silicon that are distinctly different from the von Neumann model. Beyond this, quantum simulators, which are the quantum equivalent of analogue computers, may be constructable in the near future

    Architecture and Design of Medical Processor Units for Medical Networks

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    This paper introduces analogical and deductive methodologies for the design medical processor units (MPUs). From the study of evolution of numerous earlier processors, we derive the basis for the architecture of MPUs. These specialized processors perform unique medical functions encoded as medical operational codes (mopcs). From a pragmatic perspective, MPUs function very close to CPUs. Both processors have unique operation codes that command the hardware to perform a distinct chain of subprocesses upon operands and generate a specific result unique to the opcode and the operand(s). In medical environments, MPU decodes the mopcs and executes a series of medical sub-processes and sends out secondary commands to the medical machine. Whereas operands in a typical computer system are numerical and logical entities, the operands in medical machine are objects such as such as patients, blood samples, tissues, operating rooms, medical staff, medical bills, patient payments, etc. We follow the functional overlap between the two processes and evolve the design of medical computer systems and networks.Comment: 17 page

    Aid unpredictability and absorptive capacity: analyzing disbursement delays in Africa.

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    This paper examines the extent to which aid disbursement delays could be used as an indicator of the aid unpredictability and absorptive capacity in recipient countries. Since many recipient countries are dependent on aid, disbursement delays might matter for its effectiveness. The emphasis is put on the so-called pipeline approach, according to which, in the short run, disbursement constraints may lead to huge delays and weak rates of aid disbursement relative to commitments. After the literature review on disbursement delays, we use the framework of programmable aid to run some econometric estimations through a dynamic model, an ARDL, for a panel of 48 African countries during the period of 1975–2008. We find disbursement constraints mainly at the short-run level, while the main donor's specific factors seem to be the selectivity and the degree of aid fragmentation. Disbursement rates and rhythms are also influenced by the economic performance and governance quality of the recipient countries and the share of grants in aid modalities. Bilateral donors are found to under-perform in comparison with multilateral donors in terms of the rhythm of aid disbursement.Foreign aid, absorptive capacity, disbursement delays, panel ARDL
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