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21.
A survey and taxonomy on energy efficient resource allocation techniques for cloud computing systems
Abdul Hameed Alireza Khoshkbarforoushha Rajiv Ranjan Prem Prakash Jayaraman Joanna Kolodziej Pavan Balaji Sherali Zeadally Qutaibah Marwan Malluhi Nikos Tziritas Abhinav Vishnu Samee U. Khan Albert Zomaya 《Computing》2016,98(7):751-774
In a cloud computing paradigm, energy efficient allocation of different virtualized ICT resources (servers, storage disks, and networks, and the like) is a complex problem due to the presence of heterogeneous application (e.g., content delivery networks, MapReduce, web applications, and the like) workloads having contentious allocation requirements in terms of ICT resource capacities (e.g., network bandwidth, processing speed, response time, etc.). Several recent papers have tried to address the issue of improving energy efficiency in allocating cloud resources to applications with varying degree of success. However, to the best of our knowledge there is no published literature on this subject that clearly articulates the research problem and provides research taxonomy for succinct classification of existing techniques. Hence, the main aim of this paper is to identify open challenges associated with energy efficient resource allocation. In this regard, the study, first, outlines the problem and existing hardware and software-based techniques available for this purpose. Furthermore, available techniques already presented in the literature are summarized based on the energy-efficient research dimension taxonomy. The advantages and disadvantages of the existing techniques are comprehensively analyzed against the proposed research dimension taxonomy namely: resource adaption policy, objective function, allocation method, allocation operation, and interoperability. 相似文献
22.
Singh Siddharth Rathore Vivek Singh Singh Rajiv 《Multimedia Tools and Applications》2017,76(3):3557-3575
Multimedia Tools and Applications - Medical image watermarking is a challenging area of research. High bandwidth, secure transmission of patient’s data among hospitals and hiding capacity are... 相似文献
23.
24.
Dynamic slicing is a promising trace based technique that helps programmers in the process of debugging. In order to debug a failed run, dynamic slicing requires the dynamic dependence graph (DDG) information for that particular run. The two major challenges involved in utilizing dynamic slicing as a debugging technique are the efficient computation of the DDG and the efficient computation of the dynamic slice, given the DDG. In this paper, we present an efficient debugger, which first computes the DDG efficiently while the program is executing; dynamic slicing is later performed efficiently on the computed DDG, on demand. To minimize program slowdown during the online computation of DDG, we make the design decision of not outputting the computed dependencies to a file, instead, storing them in memory in a specially allocated fixed size circular buffer. The size of the buffer limits the length of the execution history that can be stored. To maximize the execution history that can be maintained, we introduce optimizations to eliminate the storage of most of the generated dependencies, at the same time ensuring that those that are stored are sufficient to capture the bug. Experiments conducted on CPU‐intensive programs show that our optimizations are able to reduce the trace rate from 16 to 0.8 bytes per executed instruction. This enables us to store the dependence trace history for a window of 20 million executed instructions in a 16‐MB buffer. Our debugger is also very efficient, yielding slicing times of around a second, and only slowing down the execution of the program by a factor of 19 during the online tracing step. Using recently proposed architectural support for monitoring, we are also able to handle multithreaded programs running on multicore processors. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
25.
Correlation between ionic conductivity and fluidity of polymer gel electrolytes containing NH4CF3SO3
Nonaqueous polymer gel electrolytes containing ammonium triflate (NH4CF3SO3) and dimethylacetamide (DMA) with polymethylmethacrylate (PMMA) as the gelling polymer have been synthesized which show high
value of conductivity (~ 10-2 S/cm) at 25°C. The conductivity of polymer gel electrolytes containing different concentrations of NH4CF3SO3 shows a small decrease with the addition of PMMA and this has been correlated with the variation of fluidity of these gel
electrolytes. The small decrease in conductivity with PMMA addition shows that polymer plays the role of stiffener and this
is supported by FTIR results which also indicates the absence of any active interaction between polymer and NH4CF3SO3 in these gel electrolytes. 相似文献
26.
Kaushik Patel Jagdish Prajapati Rajiv Vaidya S. G. Patel 《Bulletin of Materials Science》2005,28(5):405-410
Single crystals of the lamellar compound, ZrSe3, were grown by chemical vapour transport technique using iodine as a transporting agent. The grown crystals were characterized
with the help of energy dispersive analysis by X-ray (EDAX), which gave confirmation about the stoichiometry. The optical
band gap measurement of as grown crystals was carried out with the help of optical absorption spectra in the range 700–1450
nm. The indirect as well as direct band gap of ZrSe3 were found to be 1.1 eV and 1.47 eV, respectively. The resistivity of the as grown crystals was measured using van der Pauw
method. The Hall parameters of the grown crystals were determined at room temperature from Hall effect measurements. Electrical
resistivity measurements were performed on this crystal in the temperature range 303–423 K. The crystals were found to exhibit
semiconducting nature in this range. The activation energy and anisotropy measurements were carried out for this crystal.
Pressure dependence of electrical resistance was studied using Bridgman opposed anvils set up up to 8 GPa. The semiconducting
nature of ZrSe3 single crystal was inferred from the graph of resistance vs pressure. The results obtained are discussed in detail. 相似文献
27.
Discontinuity-Preserving Surface Reconstruction Using Stochastic Differential Equations 总被引:1,自引:0,他引:1
We address the problem of reconstructing a surface from irregularly spaced sparse and noisy range data while concurrently identifying and preserving the significant discontinuities in depth. It is well known that, starting from either the probabilistic Markov random field model or the mechanical membrane or thin plate model for the surface, the solution of the reconstruction problem can be eventually reduced to the global minimization of a certain “energy” function. Requiring the preservation of depth discontinuities makes the energy function nonconvex and replete with multiple local minima. We present a new method for obtaining discontinuity-preserving reconstruction based on the numerical solution of an appropriate Ito vector stochastic differential equation (SDE). The reconstructed surface is found by following the sample path of the (stochastic) diffusion process that solves the SDE in question. Our central contribution is the demonstration of the efficacy of the stochastic differential equation technique for solving a vision problem. Through comparisions of the results of our method to those of the two well-known existingglobalminimization based reconstruction techniques, we show a significant improvement in the final reconstructions obtained. 相似文献
28.
Due to the exponential growth of the Internet users and wireless devices, interests on home networks have been enormously increased in recent days. In digital home networks, home services including remote access and control to home appliances as well as services offered by service providers are alluring. However, the remote control services cause digital home networks to have various security threats. Hence, for digital home networks, robust security services, especially remote user authentication, should be considered. This paper presents a robust and efficient authentication scheme based on strong-password approach to provide secure remote access in digital home network environments. The proposed scheme uses lightweight computation modules including hashed one-time password and hash-chaining technique along with low-cost smart card technology. It aims to satisfy several security requirements including stolen smart card attack and forward secrecy with lost smart card as well as functional requirements including no verification table and no time synchronization. Comparing with the existing representative schemes, it can be validated that the proposed scheme is more robust authentication mechanism having better security properties. We have conducted formal verification of the proposed scheme. 相似文献
29.
Application software for Intel's 8052AH-basic microcontroller can be developed in MCS basic-52, an enhanced version of basic, using the onchip basic interpreter. The paper explores the 8052AH-basic device and its language in comparison with the standard Microsoft basic and presents some software routines and other guidelines for programmers. Control-oriented applications, as opposed to conventional number-crunching applications, are emphasized. The paper also discusses how the resources of the Intellec development system can be used to facilitate the development of application software. 相似文献
30.
Arun Kumar Rajiv Ranjan Kumar Brahm Deo Sharma Sanjod Kumar Mendiratta Deepak Sharma 《Critical reviews in food science and nutrition》2015,55(10):1340-1351
The adulteration/substitution of meat has always been a concern for various reasons such as public health, religious factors, wholesomeness, and unhealthy competition in meat market. Consumer should be protected from these malicious practices of meat adulterations by quick, precise, and specific identification of meat animal species. Several analytical methodologies have been employed for meat speciation based on anatomical, histological, microscopic, organoleptic, chemical, electrophoretic, chromatographic, or immunological principles. However, by virtue of their inherent limitations, most of these techniques have been replaced by the recent DNA-based molecular techniques. In the last decades, several methods based on polymerase chain reaction have been proposed as useful means for identifying the species origin in meat and meat products, due to their high specificity and sensitivity, as well as rapid processing time and low cost. This review intends to provide an updated and extensive overview on the DNA-based methods for species identification in meat and meat products. 相似文献