the following topics are dealt with: business process modeling and management; middleware frameworks; security and enterprise computing; enterprise architecture; modeling enterprise systems; policy and enterprise comp...
the following topics are dealt with: business process modeling and management; middleware frameworks; security and enterprise computing; enterprise architecture; modeling enterprise systems; policy and enterprise computing; architectural models; workflow; model-driven architecture; electronic contracts; business process and rules; requirements; secured services; quality of service; requirements based on development and strategic planning; and policy in enterprise systems.
Current Radio-Frequency Identification (RFID) technology involves two types of physical devices: tags and reader. the reader combines in a single physical device transmission (to the tags) and reception (from the tags...
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ISBN:
(纸本)9781450301824
Current Radio-Frequency Identification (RFID) technology involves two types of physical devices: tags and reader. the reader combines in a single physical device transmission (to the tags) and reception (from the tags) functions. In this paper we discuss an alternative approach, where receive functions are performed by a separate device called "RFID listener". this allows distributed tag-sensing schemes where one transmitter coexists with multiple listeners. We discuss pros and cons of both approaches and present our implementation of a passive RFID listener on GNU Radio. Our implementation is a basis for experimenting with future distributed listener-based systems, but it can be also used as a cheap and flexible protocol analyzer for currently available commercial RFID readers.
Complex Event Processing (CEP) and Mobile Adhoc networks (MANETs) are two technologies that can be used to enable monitoring applications for Emergency and Rescue missions (ER). MANETs are characterized by energy limi...
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ISBN:
(纸本)9781467377010
Complex Event Processing (CEP) and Mobile Adhoc networks (MANETs) are two technologies that can be used to enable monitoring applications for Emergency and Rescue missions (ER). MANETs are characterized by energy limitations, and in-network processing or distributed CEP is one possible solution. Operator placement mechanism for distributed CEP has a direct impact on energy consumption. Existing operator placement mechanisms focus on static network topologies and are therefore inappropriate for MANETs scenarios. We propose a novel energy efficient decentralized distributed placement mechanism, designed to achieve fast convergence with minimal data transmission cost while achieving a near optimal placement assignment. We compare our decentralized placement mechanism with a centralized approach under different mobility scenarios. Furthermore, we evaluate the distributed CEP under different workload scenarios in order to gain additional insight into different performance characteristics of the system. Finally, we measure the impact of a simple placement replication scheme on the overall system performance in terms of delay and message overhead. Our decentralized placement mechanism achieves up to almost 50% lower message overhead compared to the centralized approach, and it has lower message overhead across different mobility scenarios compared to the centralized approach. the placement replication scheme achieves up to 51% lower delay compared to the decentralized placement mechanism with no replication.
In this paper, we introduce a scheme of caching requested data in LTE networks. After data (eg., web pages) is cached after its first request, the subsequent requests of the same data are served from the network's...
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ISBN:
(纸本)9781467377010
In this paper, we introduce a scheme of caching requested data in LTE networks. After data (eg., web pages) is cached after its first request, the subsequent requests of the same data are served from the network's caching memory directly. the idea in this scheme is new in that the caching memory is at the level of the mobile devices themselves and not in the LTE core network, as in other proposed schemes. Our approach aims to minimize the required changes in the functions of the various elements of the LTE network core for supporting the caching operations. As we illustrate in the results section, the proposed system results in lower overall data access delays, which are attributed to retrieving some of the requested data from Internet servers when such data are not found in the network.
Modern computationally-heavy applications are often time-sensitive, demanding distributed strategies to accelerate them. On the other hand, distributedcomputing suffers from the bottleneck of slow workers in practice...
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ISBN:
(数字)9781665486279
ISBN:
(纸本)9781665486279
Modern computationally-heavy applications are often time-sensitive, demanding distributed strategies to accelerate them. On the other hand, distributedcomputing suffers from the bottleneck of slow workers in practice. distributed coded computing is an attractive solution that adds redundancy such that a subset of distributed computations suffices to obtain the final result. However, the final result is still either obtained within a desired time or not, and for the latter, the resources that are spent are wasted. In this paper, we introduce the novel concept of layered-resolution distributed coded computations such that lower resolutions of the final result are obtained from collective results of the workers - at an earlier stage than the final result. this innovation makes it possible to have more effective deadline-based systems, since even if a computational job is terminated because of timing, an approximated version of the final result can be released. Based on our theoretical and empirical results, the average execution delay for the first resolution is notably smaller than the one for the final resolution. Moreover, the probability of meeting a deadline is one for the first resolution in a setting where the final resolution exceeds the deadline almost all the time, reducing the success rate of the systems with no layering.
Large scale multiple-input multiple-output (MIMO) system is draining attention for its huge spectral efficiency. However, this is only applicable if the base-station is provided with an accurate channel-state informat...
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ISBN:
(纸本)9781467377010
Large scale multiple-input multiple-output (MIMO) system is draining attention for its huge spectral efficiency. However, this is only applicable if the base-station is provided with an accurate channel-state information (CSI). In practical cases, the feedback channel is limited, especially when a large antenna array is used making CSI compression mandatory. therefore, compressive sensing (CS) can be applied to massive MIMO systems, where spatial correlation between the antenna array elements is exploited to obtain sparse representations of the downlink channel. Moreover, the correlation among nearby users seeing similar scatterers can be utilized to recover the CSI at the base-station using distributed compressive sensing (DCS) with a limited amount of errors. Our unique link-level simulation shows the suitability of CS and DCS to reduce the amount of channel feedback to less than 37% and still achieves a very low symbol-error ratio (SER) error floor and high per-user capacity.
In order to accommodate the exponentially-growing data traffic, LTE operators are considering the extension of the LTE operation into the unlicensed bands. In a recent technical report for the third Generation Partner...
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ISBN:
(纸本)9781467377010
In order to accommodate the exponentially-growing data traffic, LTE operators are considering the extension of the LTE operation into the unlicensed bands. In a recent technical report for the third Generation Partnership Project, Licensed-Assisted Access (LAA) to the unlicensed spectrum has been introduced. the report and other works in the literature reveal coexistence challenges that are raised when the LTE system coexists with other technologies such as WiFi, with fairness being the primary challenge. In this work, we propose a preliminary design for a semi-distributed LTE-Unlicensed scheme where the LTE Base Station uses WiFi-like carrier sense, back-off, and Quality of Service facility techniques. We also present a study on LAA-WiFi-coexistence through ns3 simulations. We conclude from our simulations that our preliminary design can achieve fairness in a limited set of scenarios, and we highlight the requirements and challenges that need to be considered in future work for designing a fair scheme for a wider set of scenarios.
the 11thinternational Symposium on distributedcomputing and Artificial Intelligence 2014 (DCAI 2014) is a forum to present applications of innovative techniques for studying and solving complex problems. the exchang...
ISBN:
(数字)9783319075938
ISBN:
(纸本)9783319075921;9783319075938
the 11thinternational Symposium on distributedcomputing and Artificial Intelligence 2014 (DCAI 2014) is a forum to present applications of innovative techniques for studying and solving complex problems. the exchange of ideas between scientists and technicians from boththe academic and industrial sector is essential to facilitate the development of systems that can meet the ever-increasing demands of todays society. the present edition brings together past experience, current work and promising future trends associated withdistributedcomputing, artificial intelligence and their application in order to provide efficient solutions to real *** years technical program presents both high quality and diversity, with contributions in well-established and evolving areas of research (Algeria, Brazil, China, Croatia, Czech Republic, Denmark, France, Germany, Ireland, Italy, Japan, Malaysia, Mexico, Poland, Portugal, Republic of Korea, Spain, Taiwan, Tunisia, Ukraine, United Kingdom), representing a truly wide area network of research activity. DCAI'14 Special Sessions have been a very useful tool in order to complement the regular program with new or emerging topics of particular interest to the participating community. Special Sessions that emphasize on multi-disciplinary and transversal aspects, such as AI-driven methods for Multimodal Networks and Processes Modeling and Multi-Agents Macroeconomics have been especially encouraged and *** symposium is organized by the Bioinformatics, Intelligent System and Educational Technology Research Group (http://***/) of the University of Salamanca. the present edition was held in Salamanca, Spain, from 4th to 6th June 2014.
the main criteria for designing the upcoming cellular systems are: More network capacity and less energy consumption. Recently, distributed antenna system (DAS) has received considerable attention due to its potential...
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ISBN:
(纸本)9781467377010
the main criteria for designing the upcoming cellular systems are: More network capacity and less energy consumption. Recently, distributed antenna system (DAS) has received considerable attention due to its potential to provide higher spectral efficiency and uniform coverage for cellular networks. In this regard, this article compares the performance of DAS with centralized antenna system (CAS) in LTE-Advanced system in term of cell throughput and energy efficiency (EE), where practical restrictions such as out-of-cell interference, pathloss, and small-scale fading are taken into account. Furthermore, the EE degradation is investigated under two different sleep-mode scenarios (moderate and low loaded networks) where different number of antennas are activated. Finally, we investigate the impact of channel bandwidth enhancement on the compensation of EE degradation due to the antenna muting during the sleep modes. the results reveal that DAS considerably outperforms CAS in term of EE (up to 56.6%). Furthermore, the simulation results show that during the sleep modes, by optimally assigning channel bandwidth, the EE-loss, not only can be compensated, but also EE can be significantly improved, where the proposed methodology guarantees a considerable power-saving for the cellular network (up to 27.63%).
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