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1.
An identification procedure to estimate the parameters of a thermoresistive solar radiation sensor is presented. The proposed technique employs only electrical excitation for the sensor. The estimation algorithm is recursive and is applied to the sensor model derived from the thermodynamic equilibrium differential equations. The simulation and the experimental results demonstrate the validity of the proposed approach  相似文献   
2.
The promising potential of cloud computing and its convergence with technologies such as mobile computing, wireless networks, sensor technologies allows for creation and delivery of newer type of cloud services. In this paper, we advocate the use of cloud computing for the creation and management of cloud based health care services. As a representative case study, we design a Cloud Based Intelligent Health Care Service (CBIHCS) that performs real time monitoring of user health data for diagnosis of chronic illness such as diabetes. Advance body sensor components are utilized to gather user specific health data and store in cloud based storage repositories for subsequent analysis and classification. In addition, infrastructure level mechanisms are proposed to provide dynamic resource elasticity for CBIHCS. Experimental results demonstrate that classification accuracy of 92.59% is achieved with our prototype system and the predicted patterns of CPU usage offer better opportunities for adaptive resource elasticity.  相似文献   
3.
Various natural and man-made disasters as well as major political events (like riots) have increased the importance of understanding geographic failures and how correlated failures impact networks. Since mission critical networks are overlaid as virtual networks over a physical network infrastructure forming multilayer networks, there is an increasing need for methods to analyze multilayer networks for geographic vulnerabilities. In this paper, we present a novel impact-based resilience metric. Our new metric uses ideas borrowed from performability to combine network impact with state probability to calculate a new metric called Network Impact Resilience. The idea is that the highest impact to the mission of a network should drive its resilience metric. Furthermore, we present a state space analysis method that analyzes multilayer networks for geographic vulnerabilities. To demonstrate the methods, the inability to provision a given number of upper layer services is used as the criteria for network failure. Mapping techniques for multilayer network states are presented. Simplifying geographic state mapping techniques to reduce enumeration costs are also presented and tested. Finally, these techniques are tested on networks of varying sizes.  相似文献   
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5.
A stabilized equal‐order velocity–pressure finite element algorithm is presented for the analysis of flow in porous media and in the solidification of binary alloys. The adopted governing macroscopic conservation equations of momentum, energy and species transport are derived from their microscopic counterparts using the volume‐averaging method. The analysis is performed in a single domain with a fixed numerical grid. The fluid flow scheme developed includes SUPG (streamline‐upwind/Petrov–Galerkin), PSPG (pressure stabilizing/Petrov–Galerkin) and DSPG (Darcy stabilizing/Petrov–Galerkin) stabilization terms in a variable porosity medium. For the energy and species equations a classical SUPG‐based finite element method is employed. The developed algorithms were tested extensively with bilinear elements and were shown to perform stably and with nearly quadratic convergence in high Rayleigh number flows in varying porosity media. Examples are shown in natural and double diffusive convection in porous media and in the directional solidification of a binary‐alloy. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
6.
This short paper reports on the CNSM’2012 conference (International Conference on Network and Service Management). It presents an overview on the technical sessions, keynotes, tutorials, and panel, especially focusing on the original and dominating topics that raised the most comments and discussion. It then aims at indicating what the dominant research directions were in the network and service management community.  相似文献   
7.
In this paper, the thermoelectric performance of porous armchair graphene nanoribbons under tensile and compressive strain is investigated as a function of pore morphology and temperature. For all the porous structures irrespective of their pore size, the performance improves at a compressive strain of 10%, while for tensile nature, the minimum cut-off strain required for improved thermoelectric figure of merit (ZT) shows an inverse relation with the pore size. In addition, optimal pore shape geometry can yield better performance, even at lower values of strain. Further analysis reveals that tensile strain is not able to improve the performance at low and intermediate temperatures of around 300 K, whereas tensile/compressive strain is effective in enhancing the performance of porous armchair graphene nanoribbons at higher temperatures. Furthermore, the structures are found to be more sensitive to compressive strain than the tensile one since the effect of compressive strain is found to improve ZT more significantly. Our analysis based on Non-Equilibrium Green’s function calculations suggests a possible route for tailoring the functionality of nanomaterials so as to achieve great potentials for thermoelectric applications at various temperatures.  相似文献   
8.
Cancer is the second most common cause of death in the world. The principal limitations thus far encountered in the clinical practice of probing cancer are diverse and include low sensitivity, time consumption, bulkiness, and cost. In this respect, nanomaterial (NM)‐based sensing techniques are recognized as a superior alternative to efficiently resolve such limitations. A better understanding of NM‐based sensing platforms is thus important so that these novel avenues can easily be explored for clinical applications. These platforms have the merits of high sensitivity, high specificity, rapid response, and easy‐to‐read signals. This review offers a comprehensive survey of NM‐based advanced cancer‐sensing techniques and will help the scientific community establish optimum sensing strategies based on an accurate assessment of the interactions between cancer biomarkers and NM‐based platforms.  相似文献   
9.
钢筋砼深梁的试验研究   总被引:5,自引:0,他引:5       下载免费PDF全文
根据490个构件的试验结果和有限元分析计算,证实深梁的工作性能与一般梁不同,正截面应变不符合平截面假定,且在斜裂缝出现后的受力模型为拉杆拱。深梁的破坏形态为弯曲,剪切或弯剪破坏,但局压或锚固破坏较一般梁严重。以试验数据为基础,分析了有关参数的作用,提出了正截面强度、斜截面强度和抗裂度的回归公式与设计式,截面限制条件以及弯剪界限配筋率计算公式。这些经验公式与试验结果符合良好,设计式简便可行。此外,还对局压计算、最小配筋率、锚固长度及构造要求提出了试验分析意见与建议。  相似文献   
10.
In this paper a fuzzy interactive method is proposed for efficient management of multipurpose multireservoir problems. The proposed method provides an option to decision maker (DM) to work in an interactive manner to achieve the conflicting objectives as close to their desired values as is practically feasible. In each iteration, fuzzy membership functions of various objectives are framed and combined into a single objective using the product operator. The single objective nonlinear optimization model thus framed in each iteration is numerically solved using genetic algorithm. The solution provides the values of the objectives which can be actually achieved keeping in view their aspired values as provided by DM. At the end of each iteration, DM has the option to modify the aspired values of one or more objectives keeping in view the results obtained by the algorithm thus far. The algorithm is stopped when DM feels satisfied with the results. The working of the proposed method has been demonstrated on the mathematical model of a realistic multipurpose multireservoir system taken from literature.  相似文献   
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