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31.
This paper discusses a framework in which catalog service communities are built, linked for interaction, and constantly monitored and adapted over time. A catalog service community (represented as a peer node in a peer-to-peer network) in our system can be viewed as domain specific data integration mediators representing the domain knowledge and the registry information. The query routing among communities is performed to identify a set of data sources that are relevant to answering a given query. The system monitors the interactions between the communities to discover patterns that may lead to restructuring of the network (e.g., irrelevant peers removed, new relationships created, etc.).  相似文献   
32.
When phosphate rock is dissolved in nitric acid, phosphoric acid and uranium can be selectively extracted by tertiary amyl alcohol; other impurities including the lanthanides remain in the aqueous phase. Uranium can be recovered from the alcohol phase by selective stripping and the lanthanides from the raffinate by extraction with tributyl phosphate.  相似文献   
33.
DWT-based joint antenna selection for correlated MIMO channels   总被引:1,自引:0,他引:1  
This paper proposes a new discrete wavelet transform (DWT)-based joint antenna selection scheme for spatially correlated multiple-input multiple output (MIMO) channels. To reduce the severe performance degradation of the traditional antenna selection schemes in correlated channels, a new scheme which employ joint antenna selection (JAS) at both link ends algorithm and embed DWT operations in the receiver-end RF chains is proposed. Through extensive simulations it is demonstrated that the proposed DWT-based joint antenna selection has significant improvement of the capacity for both i.i.d and correlated MIMO channels, while requiring only a minor hardware overhead and low computational complexity for the DWT operations. Moreover, it is shown that the capacity associated with DWT-based JAS is higher than the system employing DWT-based receive antenna selection (RAS) only. This is achieved in i.i.d. and correlated MIMO channels.  相似文献   
34.
The present study describes the effects of glycerol, relative humidity (RH) and the minor components of corn flour on mechanical and thermal properties of native flour, defatted flour, and starch‐based materials. The kinetic of retrogradation for these different materials were dissimilar. For all samples, strain at break shows a maximum value as a function of RH followed by a decrease, explained by the appearance of water and glycerol clusters. Starch controls the mechanical properties of corn flour‐based material and their variations with temperature and humidity. Lipid and protein have negative effect on mechanical properties of thermoplastic flour toward starch but they did not have a plasticizing effect on the physicochemical behavior of the matrix. Tgs decreased as a result of water content increase.  相似文献   
35.
36.
Clean Technologies and Environmental Policy - The Saudi economy is driven by the energy sector which mainly derived from petroleum-based resources. Besides export, the Kingdom’s consumption...  相似文献   
37.
Recently, Wang and Ma (Quantum Inf Process 16(5):130, 2017) proposed two interesting quantum key agreement protocols with a single photon in both polarization and spatial-mode degrees of freedom. They claimed that the privacy of participants’ secret keys in the multiparty case is protected against dishonest participants. However, in this paper, we prove that two dishonest participants can deduce the secret key of an honest one using a fake sequence of single photons, without being detected. Also, we propose an additional security detection process to avoid the security loophole in their protocol.  相似文献   
38.
A bifunctional reactive disperse dye containing two temporarily anionic sulphatoethylsulphone groups was synthesised and applied to nylon 6 fabric by exhaust dyeing at a variety of pH levels and temperatures. A monofunctional reactive disperse dye containing one temporarily anionic sulphatoethylsulphone group was also synthesised, and its dyeing behaviour was compared with the bifunctional dye. The bifunctional reactive disperse dye exhibited high exhaustion and total fixation yield under alkaline conditions. The results also indicate that the introduction of two temporarily anionic sulphatoethylsulphone groups of the bifunctional dye gave an enhancement in dyeing performance compared with that of the monofunctional dye. The dyes also showed very good levelling and fastness properties on nylon 6 fabric.  相似文献   
39.
This paper presents a general methodology to improve risk assessment in the specific workshops of semiconductor manufacturers. We are concerned, in this case, with the problem of equipment failures and drifts. These failures are generally observed, with delay, during the product metrology phase. To improve the reactivity of the control system, we propose a predictive approach based on the Bayesian technique. Increased use of these techniques is the result of the advantages obtained. This approach allows early action to maintain, for example, the equipment before it can drift. Also, our contribution consists in proposing a generic model to predict the equipment health factor (EHF), which will define decision support strategies on preventive maintenance to avoid unscheduled equipment downtime. Following the proposed methodology, a data extraction and processing prototype is also designed to identify the real failure modes which will instantiate the Bayesian model. EHF results are decision support elements. They can be further used to improve production performance: reduced cycle time, improved yield and enhanced equipment effectiveness.  相似文献   
40.
Bovine M. semimembranosus from different sexes of cattle were held at temperatures ranging from 0 to 35 °C until rigor and aged for up to 9 weeks. The waterholding capacity (WHC) of the beef increased with ageing as evidenced by the decline in drip loss measured gravimetrically, centrifugally and by pressure. Drip viscosity (P < 0.01), meat protein extractability (P < 0.05), spreadability (P < 0.01) and compressibility also increased with ageing. Evidence of structural changes was seen in SDS-PAGE confirming the physical changes. Meat spreadability under pressure and WHC were higher in samples with inherently higher pH relative to lower pH. The outcome of this study supports a hypothesis that the increase in WHC with ageing is due to the breakdown in meat structure and the creation of “sponge effect”, which disrupts the channels through which moisture is lost and physically entraps the free water in meat and reduce the amount that drips out.  相似文献   
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