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71.
In this study, a fiber-blowing process was utilized to prepare mineral fibers from water-quenched slags to raise the additional value of the recycled slag. Based on their excellent physical and thermal properties, slag fibers were added into a phenol–formaldehyde matrix followed by thermal curing to produce slag fiber-based composites. The friction and wear tests were applied to evaluate the tribological performance of the slag fiber-based composites. Although the optimum process parameters are still under investigation, however, it appeared that slag fiber prepared by this study shows its potential for use in frictional composites based on our results.  相似文献   
72.
Guna  Jože  Geršak  Gregor  Humar  Iztok  Krebl  Maja  Orel  Marko  Lu  Huimin  Pogačnik  Matevž 《Mobile Networks and Applications》2020,25(4):1436-1445
Mobile Networks and Applications - VR sickness (Cybersickness) presents an important challenge in virtual reality environments. We present the results of a study on the effects of VR technology and...  相似文献   
73.
The human body has developed a thermo‐regulatory system that maintains an inner body temperature of approximately 37 °C. At excessive body temperatures, sweat mechanisms activate, resulting in a decrease in body temperature through sweat evaporation. Garments, depending on their characteristics, extensively affect the heat interchange process between the human body and the environment. Different printing processes change the characteristics of textile materials and therefore the garments made from these materials. This paper investigates the influence of digital printing parameters on the thermo‐physiological features of textile materials. The effects of printing parameters on thermo‐physiological characteristics of substrate materials were determined by measuring water vapour resistance. The obtained results show that printing parameters, in combination with material composition and material texture, have a large effect on the thermo‐physiological characteristics of textiles.  相似文献   
74.
A low temperature process to fabricate high resolution metallic lines on indium tin oxide (ITO) substrates using inkjet printing and subsequent electroless plating is described in this study. In this method, a thermo-sensitive (styrene-co-NIPAAm)/Pd (St-co-NIPAAm/Pd) nanoparticle-based ink was printed onto ITO substrates to create patterned catalytic sites, where nickel is subsequently deposited by electroless plating to form metal lines with desired width and conductivity. The inkjet printing variables such as droplet spacing and printing voltage, as well as the Ni electroless deposition variables such as deposition time and temperature were systematically investigated to obtain the optimum parameters. The adhesion of the deposited Ni–P coating to the ITO substrate was evaluated by a scotch tape test method. Optical microscope observation shows that a continuous pattern was formed with a printing voltage of 37 V and a droplet spacing of 50 μm. The irritating coffee ring effect was significantly suppressed by raising the substrate temperature to 50 °C and increasing the electroless plating temperature to 75 °C. High-resolution conductive metal lines can be easily and successfully fabricated using our method, which shows good potential for preparing the metallic lines as front or back electrodes in solar cells.  相似文献   
75.
Customs continue to use a wide range of technology in protecting against terrorism and the movement of illicit trade and prohibited imports. The throughput of scanned vehicles and cargo increases and just keeps on growing. Therefore, the need of automated algorithms to help screening officers in inspection, examination or surveillance of vehicles and containers is crucial. In this context, the successful collaboration between manufacturers and customs offices is of key importance. Facing this topic, within the seventh framework program of the European Commission, the project ACXIS “Automated Comparison of X-ray Images for cargo Scanning” arose. The main objective of this project is to develop a manufacturer independent reference database for X-ray images of illicit and licit cargo. Historic images of real detections, images of illegal cargo mock-ups as well as images of legitimate cargo will be integrated into the reference database. For this, procedures and algorithms to uniform X-ray images of different cargo scanners was developed, as well as an automated identification method of potentially illicit cargo. Finally, these developments were incorporated in creating a training simulator and a toolbox for inspection officers enhanced X-ray screening competence.  相似文献   
76.
Results obtained on the intensity fluctuations of flat-topped Gaussian beams in weakly turbulent non-Kolmogorov horizontal atmospheric optics links are represented. Effects on the scintillation index of the power law α that describes the non-Kolmogorov spectrum are examined. Our results correctly reduce to the existing intensity fluctuations of flat-topped beams in Kolmogorov turbulence. Variation of the scintillation index against non-Kolmogorov power law α exhibits a peak at the worst power law α(w), which happens to be smaller than the Kolmogorov power law of 11/3. If the power law is smaller (larger) than α(w), increase in α will increase (decrease) the intensity fluctuations. Evaluation of the scintillation index at the worst power law results in smaller fluctuations for a Gaussian beam at short propagation distances; however, at long propagation distances flatter beams happen to possess smaller fluctuations. The scintillation change versus the source size follows a similar trend regardless whether the flat-topped beam propagates in a Kolmogorov or non-Kolmogorov medium.  相似文献   
77.
此项目包括设计、施工、预算,还有信息管理小组和当地税务局及资金的利用率。信息管理小组和当地税务局是该大楼的使用者计、施工、维护和运作模式都能反映出这一点。年高达1320万英镑。DUO^2的竞标评估标;佳是质量、费用以他们是政府建设机构的代表。  相似文献   
78.
A simultaneous annealing effect on the electroless-plated copper films deposited using the non-isothermal deposition (NITD) method was demonstrated. The Cu films were deposited onto NiMoP/Si substrates and their properties, such as microstructure, resistivity, and crystalline texture, were studied. At a deposition temperature of 400 °C, we found that the resistivity of the as-deposited Cu films was as low as 2.4 μΩ·cm, and X-ray diffraction showed a remarkable (111)/(200) peak ratio of 18.7. It reveals that the NITD system has an excellent capability to deposit and anneal a metal film in one step and does not require any post-annealing process.  相似文献   
79.
The message delay in mobile ad hoc networks   总被引:6,自引:0,他引:6  
Robin  Philippe  Ger 《Performance Evaluation》2005,62(1-4):210-228
A stochastic model is introduced that accurately models the message delay in mobile ad hoc networks where nodes relay messages and the networks are sparsely populated. The model has only two input parameters: the number of nodes and the parameter of an exponential distribution which describes the time until two random mobiles come within communication range of one another. Closed-form expressions are obtained for the Laplace–Stieltjes transform of the message delay, defined as the time needed to transfer a message between a source and a destination. From this we derive both a closed-form expression and an asymptotic approximation (as a function of the number of nodes) of the expected message delay. As an additional result, the probability distribution function is obtained for the number of copies of the message at the time the message is delivered. These calculations are carried out for two protocols: the two-hop multicopy and the unrestricted multicopy protocols. It is shown that despite its simplicity, the model accurately predicts the message delay for both relay strategies for a number of mobility models (the random waypoint, random direction and the random walker mobility models).  相似文献   
80.
Laboratory treatment of soybean oil were carried out at the following conditions: atmospheric pressure in the presence of air or nitrogen at different temperatures ranging from 160 to 250°C for 12 to 72 h. These conditions were used to study geometric isomerization of cis,cis-linoleic and cis,cis,cis-linolenic acid in the presence or in the absence of oxidative degradation reactions. Based on these experiments, a model of consecutive, parallel reactions was developed to describe the reaction steps occurring in the soybean oil during heating at constant temperature. For both cis,cis-linoleic and cis,cis,cis-linolenic acid, the reaction of formation isomers followed a first-order reaction, and the rate constant of isomerization varied according to the Arrhenius law. The isomerization rate constant for linoleic acid was 9.57×10−3±0.50 h−1 in the presence of oxygen and 7.39×10−3±0.39 h−1 in its absence, and the isomerization rate constant for linolenic acid was 1.18×10−1±0.10 h−1 in the presence of oxygen and 0.87×10−1±0.07 h−1 in its absence (all obtained at 250°C).  相似文献   
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