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81.
SALAHELDIN Ali Aboulkhsam 《计算机辅助绘图.设计与制造(英文版)》2009,19(1):102-108
Face-to-face Videoconferencing is a popular option for many large organizations because it minimizes the need for travel. Instead of continually paying for traveling expenses, a company can either pay to set up a high speed network which has many usages (including videoconferencing) or they can rent time on an existing network. Employees will also no longer be burdened with the need to travel. While face-to-face videoconferencing performance is heavily influenced by the underlying hardware and software, a g... 相似文献
82.
Automatic onset detection and picking algorithm has been proposed by applying the spectro-ratio on time–frequency sub-band. The proposed algorithm does not need any parameter settings as it will work on data generated by either short or very broad band seismometers. Our algorithm is applied on local events from Cairo region recorded by three stations of the Egyptian National Seismic Network (ENSN). Maximum standard deviation is observed to be 0.113 s of the corresponding manual picks made by analysts. 相似文献
83.
Oznur Ozkasap Mine Caglar Ali Alagoz 《Journal of Network and Computer Applications》2009,32(3):666-683
We propose and design a peer-to-peer system, SeCond, addressing the distribution of large sized content to a large number of end systems in an efficient manner. In contrast to prior work, it employs a self-organizing epidemic dissemination scheme for state propagation of available blocks and initiation of block transmissions. In order to exploit heterogeneity of peers, enhance the utilization of system resources and for the ease of deployment, scalability, and adaptivity to dynamic peer arrivals/departures, we propose mechanisms for adjusting protocol parameters dynamically according to the bandwidth usages. We describe design and analysis details of our protocol SeCond. Comprehensive performance evaluations and comparison with the BitTorrent system model have been accomplished for a wide range of scenarios. Performance results include scalability analysis for different arrival/departure patterns, flash-crowd scenario, overhead analysis, and fairness ratio. The major metrics we study include the average file download time, load on the primary seed, uplink/downlink utilization, and communication overhead. We show that SeCond is a scalable and adaptive protocol which takes the heterogeneity of the peers into account. The protocol is as fair as BitTorrent although it has no explicit strategy addressing free-riding. We also illustrate the applicability of an analytical fluid model to the behavior of SeCond. 相似文献
84.
Measuring robustness of computing systems 总被引:1,自引:0,他引:1
System builders are becoming increasingly interested in robust design. We believe that a methodology for generating robustness metrics will help the robust design research efforts and, in general, is an important step in the efforts to create robust computing systems. The purpose of the research in this paper is to quantify the robustness of a resource allocation, with the eventual objective of setting a standard that could easily be instantiated for a particular computing system to generate a robustness metric. The paper exposes how not considering the uncertainties can result in gross overestimation of the system capacity, and shows a method for reducing the impact of uncertainty, and even use it to our advantage if the uncertainties are correlated. We present our theoretical foundation for a robustness metric and give its instantiation for a particular system. 相似文献
85.
Ali Asgar S. Bhagat Sathyakumar S. Kuntaegowdanahalli Ian Papautsky 《Microfluidics and nanofluidics》2009,7(2):217-226
In this paper, we describe a simple passive microfluidic device with rectangular microchannel geometry for continuous particle
filtration. The design takes advantage of preferential migration of particles in rectangular microchannels based on shear-induced
inertial lift forces. These dominant inertial forces cause particles to move laterally and occupy equilibrium positions along
the longer vertical microchannel walls. Using this principle, we demonstrate extraction of 590 nm particles from a mixture
of 1.9 μm and 590 nm particles in a straight microfluidic channel with rectangular cross-section. Based on the theoretical
analysis and experimental data, we describe conditions required for predicting the onset of particle equilibration in square
and rectangular microchannels. The microfluidic channel design has a simple planar structure and can be easily integrated
with on-chip microfluidic components for filtration and extraction of wide range of particle sizes. The ability to continuously
and differentially equilibrate particles of different size without external forces in microchannels is expected to have numerous
applications in filtration, cytometry, and bioseparations. 相似文献
86.
Houssein Essam H. Hosney Mosa E. Mohamed Waleed M. Ali Abdelmgeid A. Younis Eman M. G. 《Neural computing & applications》2023,35(7):5251-5275
Neural Computing and Applications - Feature selection (FS) is one of the basic data preprocessing steps in data mining and machine learning. It is used to reduce feature size and increase model... 相似文献
87.
Ahmadi Kourosh Dadashtabar Rashidi Ali Jabar Moghri Ali Massomi 《The Journal of supercomputing》2022,78(15):17309-17347
The Journal of Supercomputing - On the battlefield, early detection of armored vehicles can have a positive effect. Because according to this issue, timely and appropriate reactions can be done.... 相似文献
88.
Ali Alkhalifah 《计算机系统科学与工程》2022,42(2):639-658
Owing to constant changes in user needs, new technologies have been introduced to keep pace by building sustainable applications. Researchers and practitioners are keen to understand the factors that create an attractive user interface. Although the use of cross-platform applications and services is increasing, limited research has examined and evaluated cross-platforms for developing mobile applications for different operating systems. This study evaluates cross-platform features, identifying the main factors that help to create an attractive user adaptation when building sustainable applications for both Android and iOS. Flutter and React Native were selected so end-users could test their features using the cross-platform usability assessment model. Usability, satisfaction, and navigation were tested to measure the cross-platform adaptation and end-user experience. The data were analyzed using hybrid structural equation modeling (SEM) and artificial neural network (ANN) approaches. The study results show that usability and navigation both have a positive effect on adaptation on Flutter and React Native, while satisfaction only has an effect on Flutter. The navigation variable was also the most significant predictor of adaptation for both models. This study has several implications and makes contributions to the research field, to developers, and to end-users. 相似文献
89.
The Journal of Supercomputing - Fast execution of functions is an inevitable challenge in the serverless computing landscape. Inefficient dispatching, fluctuations in invocation rates, burstiness... 相似文献
90.
Dome structures provide cost-effective solutions for covering large areas without intermediate supports. In this article,
simple procedures are developed to reach the configuration of the geodesic domes. A new definition of dome optimization problems
is given which consists of finding optimal sections for elements (size optimization), optimal height for the crown (geometry
optimization) and the optimum number of elements (topology optimization) under determined loading conditions. In order to
find the optimum design, the recently developed meta-heuristic algorithm, known as the Charged System Search (CSS), is applied
to the optimum design of geodesic domes. The CSS takes into account the nonlinear response of the domes. Using CSS, the optimum
design of the geodesic domes is efficiently performed. 相似文献