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11.
The Journal of Supercomputing - In this paper, a distributed solution is presented for the composition of complex event services in the Internet of Things (IoT) environments. The composition of...  相似文献   
12.
Journal of Chemical Ecology - Entomopathogenic fungi (EPF) can be experimentally established in several plant species as endophytes. Ecological effects of EPF inoculations on plant growth and...  相似文献   
13.
This study investigates the sintering behavior of dried sewage sludge and the related sintering mechanisms, considering sintering temperature and sintering time. Experimental results indicate that the characteristics are primarily influenced by sintering temperature. When the sintering temperature is increased from 1020 to 1050 °C, the specimens’ compressive strength and bulk density increase significantly, while water absorption decreases obviously, indicating an improvement of densification due to sintering. However, the compressive strength cannot meet the requirement for traditional ceramic products due to the release of organic matters and the formation of big pores in the products. Phosphorus in sewage sludge initially takes reactions with the formation of calcium magnesium phosphate and aluminum phosphate during sintering, which are helpful for enhancing the compressive strength. So, some materials with high contents of Al could be used to enhance the compressive strength of products. Heavy metals are fixed primarily inside the sintered specimens, with the As, Pb, Cd, Cr, Ni, Cu, Zn concentrations in the leachate found to be in the range of China regulatory requirements. These results reveal the feasibility of recycling dried sewage sludge by sintering as a construction material.  相似文献   
14.
It is eminent that partial differential equations are extensively meaningful in physics, mathematics and engineering. Natural phenomena are formulated with partial differential equations and are solved analytically or numerically to interrogate the system’s dynamical behavior. In the present research, mathematical modeling is extended and the modeling solutions Helmholtz equations are discussed in the fractional view of derivatives. First, the Helmholtz equations are presented in Caputo’s fractional derivative. Then Natural transformation, along with the decomposition method, is used to attain the series form solutions of the suggested problems. For justification of the proposed technique, it is applied to several numerical examples. The graphical representation of the solutions shows that the suggested technique is an accurate and effective technique with a high convergence rate than other methods. The less calculation and higher rate of convergence have confirmed the present technique’s reliability and applicability to solve partial differential equations and their systems in a fractional framework.  相似文献   
15.
Tagged user analysis (TUA) is a generic approximate method of analyzing random access protocols for finite-user finite-buffer systems. This technique decouples the channel contention behavior from the user queuing behavior and allows the use of classical queuing theory results to be directly applicable to the analysis of finite-user finite-buffer random access methods. In this paper, we extend TUA to analyze finite buffer S-ALOHA operating over flat fading radio channels and derive expressions for system performance indices like throughput, average packet delay, blocking probability and queue length. It is shown that for a moderate number of active users, the simulation and analytical results fit closely  相似文献   
16.
The tagged user analysis (TUA) is a generic approximate method developed to analyze random access protocols for finite-user finite-buffer systems that avoids complexities of Markovian analysis by using available queueing results. In this paper, TUA method is extended to the analysis of finite buffer S-ALOHA operating over flat fading radio channels when the user population is spatially distributed. The expressions for system performance indices are derived. It is shown that for moderate number of active users, the simulation and analytical results have a close fit.  相似文献   
17.
The progress of spin rectification effect, which has the potential in powering the nanoscopic devices wirelessly, has been impeded by its low conversion efficiency. To solve this problem, a 5.8 GHz planar inverted F‐shaped antenna, which is designed to harvest radiated microwave power as well as foster a field enhanced area surrounding a permalloy (Py, Ni80Fe20) monolayer, is presented. The electric and magnetic field are enhanced by ~17.5‐fold and ~ 45‐fold, respectively. With the proposed antenna, a photovoltage of 0.85 μV can be detected in the monolayer 1.5 m away from the transmitting antenna, with input power of 30 dBm. This work provides an effective method to enhance the spin rectification effect signal in the far field region and paves the way for spintronic devices to be potentially utilized in practical wireless applications, such as quantum information, photovoltaics, and nanogenerator.  相似文献   
18.
Milk fraud poses serious problems for the dairy industry and consumers'' health. The main aim of this study was to reveal the effect of water added to milk by measuring its electrical impedance spectrum. The required sensor was designed based on the van der Pauw method to measure the electrical conductivity of milk at the frequency band of 10 Hz to 5 MHz. The bioimpedance spectrum of the milk of five different cows showed that the electrical impedance spectrum has a high potential for detecting water added to the milk (P < 0.01). The area under the Nyquist curve was introduced as a suitable index to detect water‐added milk. In addition, the characteristic frequency of the bioimpedance spectrum was used as an important index to differentiate water‐added milk from waterless milk. An electrical model was introduced to interpret the amount of water added to the milk using the characteristic frequency. Results showed that it is possible to detect raw milk from boiled milk by measuring its electrical impedance.  相似文献   
19.
In this study,Al matrix composites reinforced by 7.5 and 15 vol.%B4C particles and also monolithic Al(Al without the B4C particles) were produced by wet attrition milling and subsequent hot forward extrusion processes.The microstructure of the composites,evaluated by scanning electron microscopy(SEM),showed that the B4C particles were properly distributed in the Al matrix.Mechanical properties of the AI/B4C composites and monolithic Al were investigated by tensile,wear and hardness tests.The results revealed that with increasing content of B4C particles,the tensile strength and microhardness of composites increased but the elongation decreased.In addition,the tensile strength and microhardness of composite samples were higher than those of monolithic Al.The density measurements revealed that the density of composites decreased with increasing content of the B4C particles.  相似文献   
20.
The present study was conducted to examine various biological activities of a methanol extract of Agave attenuata leaves. GC-MS analysis of the n-hexane fraction from the extract revealed the presence of 31 compounds, with mono-2-ethylhexyl phthalate (11.37%), 1,2-benzenedicarboxylic acid (6.33%), n-docosane (6.30%) and eicosane (6.02%) as the major components. The leaves contained appreciable levels of total phenolic contents (10.541-39.35 GAE, mg/100 g) and total flavonoid contents (43.35-304.8 CE, mg/100 g). The extract and some of its fractions showed moderate antimicrobial effects. Leaves extract and fractions also exhibited a good antioxidant potential when measured by DPPH radical scavenging activity and inhibition of lipid peroxidation assays. The hemolytic effect of the plant was found to be in a range of 1.01%-2.64%. From the present study it is concluded that this plant could be used as a source of natural antioxidants and functional food nutraceutical applications.  相似文献   
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