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991.
992.
This paper presents fuzzy acoustic emission identification in high precision hard turning process based on extended subtractive cluster analysis combined with the least-square estimation method. The fuzzy identification method provides a simple way to arrive at a definite conclusion based upon the information obtained with the difficulty in understanding the exact physics of the machining process. The experimental results prove that the proposed method is efficient and feasible.  相似文献   
993.
Chemistry and physics of thin semiconducting layers of various types are subjects of intense research. Especially when nanotechnology methods such as self-assembly are involved, amazing structural and/or functional properties may appear. Also modern physical methods using variously organized plasma arrangements are able to produce uniform structures with distinctive functionality. In this review, based virtually on our own work, discussions on the preparation, structure, morphology, and function of titanium(IV) oxide nanoscopic thin films are presented. It was shown that structurally and functionally similar titanium(IV) oxide films can be prepared via completely different preparation techniques. Function tests were arranged as “primary”, covering the assessment of the light induced charge separation efficiency, and “secondary”, based on photocatalytic surface oxidations.  相似文献   
994.
A short-term aerobic stabilization of digested waste in the final methane phase was studied. The effect of aeration rate on the reduction of leachate parameters and on the rate of CO2 production and O2 assimilation was investigated. Experimental simulation of aerobic landfill stabilization was carried out using lysimeters. When testing the effect of aeration rate on the reduction of leachate indices (BOD5, COD, N-NH4+), it was reported that the most significant reduction was obtained at the highest rate of aeration and the smallest reduction of leachate indices was attained not at the lowest but at medium aeration rates. Both the rate of CO2 production and the O2 assimilation reached their highest values in the lysimeters aerated at a high rate of aeration. The proposed mathematical model which consists of a system of five differential equations describing CO2 production, O2 assimilation and the changes of organic carbon content in the leachate correspond well with the experimental data.  相似文献   
995.
A polyvinyl alcohol (PVA)-borate hydrogel-based strippable surface decontaminant containing an ammonium salt and Prussian blue (PB) was developed for the removal of 137Cs from various surfaces. This surface decontaminant can be easily prepared by the simple mixing of commercially available materials, such as PVA, borax, NH4Cl and PB, in water, and the decontaminant can be peeled off surfaces due to its high elastic property after surface decontamination. The hydrogel displayed an effective removal performance for Cs from painted cement, aluminum, stainless steel, and cement surfaces and a potential for reusability. Therefore, the PB/PVA-borate hydrogel has good potential as a new surface decontaminant.  相似文献   
996.
997.
Cloud computing enables the provisioning of resources in a reliable and on-demand manner. With the increasing importance of the network bandwidth in the Cloud environment, the networking related resources need to be optimally allocated together with the traditional Cloud computing resources. In addition, the significant growth of the global data center traffic raises the challenge of supporting demands with large bandwidth requirements for the Cloud provider. In our paper, we consider the network-efficient virtualized cloud infrastructure provisioning problem in IP over elastic optical network (IP-over-EON) based on the data center as a service model. The elastic optical network is adopted to provide spectrum and cost-efficient networking resources for large bandwidth requests in our work. We develop mixed integer linear programming formulations to construct the mathematic model for this problem and propose a cost-optimized heuristic to solve this problem. To investigate the cost and blocking rate for the served demands, different modulation formats are compared in the EON layer, and the sliceable bandwidth-variable transponders and optical traffic grooming technology are considered. The experimental results show that different modulation formats that are adopted in the EON layer will have different impacts on the total cost and demand blocking rate for the same data set size. Also the use of SBVT will reduce the total cost no matter which modulation format is adopted, and the reduction is related to the bandwidth requirement of the demands.  相似文献   
998.
999.
We illustrate the possible acceleration of cosmic rays passing through a kind of amplification channel (via diffusion modes of propagating plane-wave fronts) induced by a rotating system. Our analysis is mainly based on the quantum discrete kinetic model (considering a discrete Uehling-Uhlenbeck collision term), which has been used to study the propagation of plane (e.g., acoustic) waves in a system of rotating gases.  相似文献   
1000.
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