Wireless Mesh Networks (WMNs) are increasingly applied for various applications. Many advantages of WMNs are based on the autonomous operation of the mesh nodes. A main factor to achieve autonomy is energy-self-suffic...
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Wireless network infrastructures such as Wireless Mesh Networks (WMNs) are increasingly applied for various applications. Increasing complexity concerning configuration, organization, management and maintenance is a m...
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The target coverage is an important yet challenging problem in wireless sensor networks, especially when both coverage and energy constraints should be taken into account. Due to its nonlinear nature, previous studies...
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The target coverage is an important yet challenging problem in wireless sensor networks, especially when both coverage and energy constraints should be taken into account. Due to its nonlinear nature, previous studies of this problem have mainly focused on heuristic algorithms; the theoretical bound remains unknown. Moreover, the most popular method used in the previous literature, i.e., discretization of continuous time, has yet to be justified. This paper fills in these gaps with two theoretical results. The first one is a formal justification for the method. We use a simple example to illustrate the procedure of transforming a solution in time domain into a corresponding solution in the pattern domain with the same network lifetime and obtain two key observations. After that, we formally prove these two observations and use them as the basis to justify the method. The second result is an algorithm that can guarantee the network lifetime to be at least (1 - ε) of the optimal network lifetime, where ε can be made arbitrarily small depending on the required precision. The algorithm is based on the column generation (CG) theory, which decomposes the original problem into two sub-problems and iteratively solves them in a way that approaches the optimal solution. Moreover, we developed several constructive approaches to further optimize the algorithm. Numerical results verify the efficiency of our CG-based algorithm.
This paper reflects on existing caching concepts in proxies and stubs of component technologies and lines out their advantages and deficiencies. A new concept is introduced that averts proliferation of component stubs...
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Equipped with 512-bit wide SIMD inst d large numbers of computing cores, the emerging x86-based Intel(R) Many Integrated Core (MIC) architecture ot only high floating-point performance, but also substantial ...
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Equipped with 512-bit wide SIMD inst d large numbers of computing cores, the emerging x86-based Intel(R) Many Integrated Core (MIC) architecture ot only high floating-point performance, but also substantial off-chip memory bandwidth. The 3D FFT (three-di fast Fourier transform) is a widely-studied algorithm; however, the conventional algorithm needs to traverse the three times. In each pass, it computes multiple 1D FFTs along one of three dimensions, giving rise to plenty of rided memory accesses. In this paper, we propose a two-pass 3D FFT algorithm, which mainly aims to reduce of explicit data transfer between the memory and the on-chip cache. The main idea is to split one dimension into ensions, and then combine the transform along each sub-dimension with one of the rest dimensions respectively erence in amount of TLB misses resulting from decomposition along different dimensions is analyzed in detail. el parallelism is leveraged on the many-core system for a high degree of parallelism and better data reuse of loc On top of this, a number of optimization techniques, such as memory padding, loop transformation and vectoriz employed in our implementation to further enhance the performance. We evaluate the algorithm on the Intel(R) PhiTM coprocessor 7110P, and achieve a maximum performance of 136 Gflops with 240 threads in offload mode, which ts the vendor-specific Intel(R)MKL library by a factor of up to 2.22X.
In this paper, we present a simulation of dynamic grid environments. We consider two types of dynamicity namely: 1) dynamic job arrival and 2) dynamically changing the resource load along with dynamic job arrival. We ...
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Network virtualization is a promising approach for resource management that allows customized Virtual Networks (VNs) to be multiplexed on a shared physical infrastructure. A key function that network virtualization ...
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Network virtualization is a promising approach for resource management that allows customized Virtual Networks (VNs) to be multiplexed on a shared physical infrastructure. A key function that network virtualization can provide is Virtual Network Embedding (VNE), which maps virtual networks requested by users to a shared substrate network maintained by an Internet service provider. Existing research has worked on this, but has primarily focused on maximizing the revenue of the Internet service provider. In this paper, we consider energy-aware virtual network embedding, which aims at minimizing the energy consumption for embedding virtual networks in a substrate network. In our optimization model, we consider energy consumption of both links and nodes. We propose an efficient heuristic to assign virtual nodes to appropriate substrate nodes based on priority, where existing activated nodes have higher priority for hosting newly arrived virtual nodes. In addition, our proposed algorithm can take advantage of activated links for embedding virtual links so as to minimize total energy consumption. The simulation results show that, for all the cases considered, our algorithm can improve upon previous work by an average of 12.6% on acceptance rate, while the consumed energy can be reduced by 12.34% on average.
This paper presents a middleware and an application scenario for communication in a pervasive community which is characterized by the use of different network and service technologies. To achieve the required cross-te...
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ISBN:
(纸本)9789639799592
This paper presents a middleware and an application scenario for communication in a pervasive community which is characterized by the use of different network and service technologies. To achieve the required cross-technology communication, we organize devices and applications as members of cells with homogeneous network interfaces, and we combine these cells to a heterogeneous ensemble by a General Purpose Access Point (GPAP). The GPAP enables and organizes a flexible service-based communication between members of different cells. This paper focuses an interconnection between Bluetooth and IP-based networks using service proxying between Bluetooth SDP (Service Discovery Protocol) and Web Services. However, it can be used as a base for service proxying with a variety of other network and SOA technologies. Furthermore, we combine several ensembles by our service-oriented middleware to build a community and enable the communication between devices of different ensembles. Moreover, we look forward to explore and allow seamless roaming for mobile devices as well as their provided services inside the community. For evaluation of our middleware we use cross-technology messaging as an application scenario for a general cross-technology video and audio communication.
Currently, with the evolution of virtualization technology, cloud computing mode has become more and more popular. However, people still concern the issues of the runtime integrity and data security of cloud computing...
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Currently, with the evolution of virtualization technology, cloud computing mode has become more and more popular. However, people still concern the issues of the runtime integrity and data security of cloud computing platform, as well as the service efficiency on such computing platform. At the same time, according to our knowledge, the design theory of the trusted virtual computing environment and its core system software for such network-based computing platform is at the exploratory stage. In this paper, we believe that efficiency and isolation are the two key proprieties of the trusted virtual computing environment. To guarantee these two proprieties, based on the design principle of splitting, customizing, reconstructing, and isolation-based enhancing to the platform, we introduce TRainbow, a novel trusted virtual computing platform developing by our research *** the two creative mechanisms, that is, capacity flowing amongst VMs and VM-based kernel reconstructing, TRainbow provides great improvements (up to 42%) in service performance and isolated reliable computing environment for Internet-oriented, large-scale, concurrent services.
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