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1.
Mohammed Hawa Jamal S. Rahhal Dia I. Abu-Al-Nadi 《Peer-to-Peer Networking and Applications》2012,5(3):279-291
Peer-to-Peer (P2P) traffic has increased rapidly over the past few years, with file sharing providing the main drive behind
such traffic. In this work we perform a measurement study of the content shared over the popular BitTorrent P2P file sharing
network. We mathematically model the file size distributions of shared files after categorizing them into Audio, Video, Archive
and CD image classes. For each of these categories we look into the most popular shared file formats and investigate their
file size statistics. This provides an important milestone to building a realistic simulation framework for P2P systems, and
for future analytical modeling of P2P networks. 相似文献
2.
Aziz Romila Anwar Muhammad Waqas Jamal Muhammad Hasan Bajwa Usama Ijaz 《Neural computing & applications》2021,33(21):14707-14721
Neural Computing and Applications - Detecting and correcting misspelled words in a written text are of great importance in many natural language processing applications. Errors can be broadly... 相似文献
3.
Rajivgandhi Govindan Nadar Chenthis Kanisha Chelliah Vijayakumar Sekar Alharbi Naiyf S. Kadaikunnan Shine Khaled Jamal M. Alanzi Khalid F. Li Wen-Jun 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(10):3921-3933
Journal of Inorganic and Organometallic Polymers and Materials - The silver oxide nanoparticle was successfully synthesized using floral waste by simple one pot, cost effective method. The complete... 相似文献
4.
在二价镍配合物催化下,2,5-二溴-3-甲基噻吩格氏试剂与5,8-二溴-萘基喹喔啉和5,8-二溴-菲基喹喔啉共聚,得到相应的喹喔啉类共轭共聚物,收率分别为65%和68%。通过FT IR、1H-NM R对聚合物及中间体的结构进行了表征。聚合物的循环伏安图中,分别在0.66 V(Epa)/0.37 V(Epc)(Copo ly-m er I),0.78 V(Epa)/-0.06V(Epc)和1.26(Epa)/0.46(Epc)(Copo lym erⅡ)处观察到氧化还原峰,表明该类聚合物有电化学活性。在紫外-可见光谱中,分别在263 nm,323 nm处(Copo lym erⅠ)和299 nm,402 nm处(Copo lym erⅡ)出现吸收峰。所得聚合物分别在504 nm和513 nm处出现荧光最大发射峰。 相似文献
5.
The present investigation pertains to modeling of seawater desalination system. A simulation model was developed and verified for a small-scale reverse osmosis system. The proposed model combines material balances on the feed tank, membrane module andproduct tank with membrane mass transfer models. Finally a comprehensive simulation model has been developed incorporating the effect of mass transfer inhibition The model is non-linear differential equation representing the feed concentration as a function of operating time and space. The solution of the simultaneous differential equations was obtained using the fourth order Runge-Kutta method, due to self starting and stability. The model was verified using the experimental data from the literature [17,24]. Parameter sensitivity was carried out to select the proper step size. The simulation was run for over 1000 11 enabling a prediction of operational performance at high overall system recoveries. 相似文献
6.
A fundamental challenge in the design of Wireless Sensor Networks (WSNs) is to maximize their lifetimes especially when they have a limited and non-replenishable energy supply. To extend the network lifetime, power management and energy-efficient communication techniques at all layers become necessary. In this paper, we present solutions for the data gathering and routing problem with in-network aggregation in WSNs. Our objective is to maximize the network lifetime by utilizing data aggregation and in-network processing techniques. We particularly focus on the joint problem of optimal data routing with data aggregation en route such that the above mentioned objective is achieved. We present Grid-based Routing and Aggregator Selection Scheme (GRASS), a scheme for WSNs that can achieve low energy dissipation and low latency without sacrificing quality. GRASS embodies optimal (exact) as well as heuristic approaches to find the minimum number of aggregation points while routing data to the Base-Station (BS) such that the network lifetime is maximized. Our results show that, when compared to other schemes, GRASS improves system lifetime with acceptable levels of latency in data aggregation and without sacrificing data quality. 相似文献
7.
Sajjad Ahmad Imran Raza M. Hasan Jamal Sirojiddin Djuraev Soojung Hur Imran Ashraf 《计算机、材料和连续体(英文)》2023,74(2):2363-2377
Vehicle-to-grid technology is an emerging field that allows unused power from Electric Vehicles (EVs) to be used by the smart grid through the central aggregator. Since the central aggregator is connected to the smart grid through a wireless network, it is prone to cyber-attacks that can be detected and mitigated using an intrusion detection system. However, existing intrusion detection systems cannot be used in the vehicle-to-grid network because of the special requirements and characteristics of the vehicle-to-grid network. In this paper, the effect of denial-of-service attacks of malicious electric vehicles on the central aggregator of the vehicle-to-grid network is investigated and an intrusion detection system for the vehicle-to-grid network is proposed. The proposed system, central aggregator–intrusion detection system (CA-IDS), works as a security gateway for EVs to analyze and monitor incoming traffic for possible DoS attacks. EVs are registered with a Central Aggregator (CAG) to exchange authenticated messages, and malicious EVs are added to a blacklist for violating a set of predefined policies to limit their interaction with the CAG. A denial of service (DoS) attack is simulated at CAG in a vehicle-to-grid (V2G) network manipulating various network parameters such as transmission overhead, receiving capacity of destination, average packet size, and channel availability. The proposed system is compared with existing intrusion detection systems using different parameters such as throughput, jitter, and accuracy. The analysis shows that the proposed system has a higher throughput, lower jitter, and higher accuracy as compared to the existing schemes. 相似文献
8.
Model checking is a formal technique used to verify communication protocols against given properties. In this paper, we propose a new model checking algorithm aims at verifying systems designed as a set of autonomous interacting agents. These software agents are equipped with knowledge and beliefs and interact with each other according to protocols governed by a set of logical rules. We present a tableauased version of this algorithm and provide the soundness, completeness, termination and complexity results. A case study about an agent-based negotiation protocol and its implementation are also described. 相似文献
9.
Elmehdi Benmalek Jamal Elmhamdi Abdelilah Jilbab 《International Journal of Speech Technology》2017,20(1):179-184
Since approximately 90% of the people with PD (Parkinson’s disease) suffer from speech disorders including disorders of laryngeal, respiratory and articulatory function, using voice analysis disease can be diagnosed remotely at an early stage with more reliability and in an economic way. All previous works are done to distinguish healthy people from people with Parkinson’s disease (PWP). In this paper, we propose to go further by multiclass classification with three classes of Parkinson stages and healthy control. So we have used 40 features dataset, all the features are analyzed and 9 features are selected to classify PWP subjects in four classes, based on unified Parkinson’s disease Rating Scale (UPDRS). Various classifiers are used and their comparison is done to find out which one gives the best results. Results show that the subspace discriminant reach more than 93% overall classification accuracy. 相似文献
10.
A class of Lyapunov functions is proposed for discrete-time linear systems interconnected with a cone bounded nonlinearity. Using these functions, we propose sufficient conditions for the global stability analysis, in terms of linear matrix inequalities (LMI), only taking the bounded sector condition into account. Unlike frameworks based on the Lur’e-type function, the additional assumptions about the derivative or discrete variation of the nonlinearity are not necessary. Hence, a wider range of cone bounded nonlinearities can be covered. We also show that there is a link between global stability LMI conditions based on this new Lyapunov function and a transfer function of an auxiliary system being strictly positive real. In addition, the novel function is considered in the local stability analysis problem of discrete-time Lur’e systems subject to a saturating feedback. A convex optimization problem based on sufficient LMI conditions is formulated to maximize an estimate of the basin of attraction. Another specificity of this new Lyapunov function is the fact that the estimate is composed of disconnected sets. Numerical examples reveal the effectiveness of this new Lyapunov function in providing a less conservative estimate with respect to the quadratic function. 相似文献