In this paper, we establish nonlinear GP model between impact factor of sci-tech journal and related indexes based on genetic programming approach. The proposed GP model utilizes average authors, number of district, n...
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In this paper, we establish nonlinear GP model between impact factor of sci-tech journal and related indexes based on genetic programming approach. The proposed GP model utilizes average authors, number of district, number of affiliation, international paper ratio and foundation paper ratio as the inputs, and uses impact factor as the output. The journals data from Chinese S&T Journal Citation Reports in 2005 are used as experimental data. The experimental results show that impact factor is mainly related to average authors and foundation paper ratio, and nearly has nothing to do with number of district, number of affiliation and international paper ratio. Therefore, increasing the average authors and foundation paper ratio of sci-tech journal will help to promote the impact factor of journal and improve the quality of journal to some extent.
In real life, people always move according to a certain paths, for example, walking from one side of corridor to the other side of it, but not passing through the wall, and so on. Therefore, all kinds of possible path...
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In real life, people always move according to a certain paths, for example, walking from one side of corridor to the other side of it, but not passing through the wall, and so on. Therefore, all kinds of possible paths could be predefined, then the indoor positioning systems can make full use of these paths to further improve the positioning accuracy. In this paper, an indoor positioning algorithm based on path tracking assistance is presented which makes the most of path information in indoor environment to optimize the searched subspaces of positioning algorithm. Experimental results demonstrated that the proposed path tracking assistance algorithm can improve the 73% accuracy in 3 meters of traditional kNN algorithm to 92% in a typical office building testbed when the subspaces are defined rationally.
The ability to fabricate high precision micro- to nanoscale structure in a wide variety of materials is of crucial importance for the advancement of microtechnology, nanotechnology and nanoscience. Also, the ability t...
The ability to fabricate high precision micro- to nanoscale structure in a wide variety of materials is of crucial importance for the advancement of microtechnology, nanotechnology and nanoscience. Also, the ability to create micrometer and sub-micrometer architecture for functional ceramics is a prerequisite of exploring the rich field of ceramic nanotechnology. In this work we fabricated three-dimensional oxide ceramic materials with fine-structure over multiple length scales by combining replication patterning technique, polyvinyl alcohol (PVA), oxide ceramic material (TiO2) nano-sized particles. Our study is based on the idea that PVA can be easily detached from a mold by peeling. We confirmed that micron and sub-micron-sized fine-structured oxide ceramic patterns containing nano-sized pores could be fabricated using this procedure. The results presented demonstrate the compositional and structural diversities that are possible with a facile approach and simple method.
Very uniform and well shaped Mn 3 O 4 nano-octahedra are synthesized using a simple hydrothermal method under the help of polyethylene glycol (PEG200) as a reductant and shape-directing agent. The nano-octahedra forma...
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Very uniform and well shaped Mn 3 O 4 nano-octahedra are synthesized using a simple hydrothermal method under the help of polyethylene glycol (PEG200) as a reductant and shape-directing agent. The nano-octahedra formation mechanism is monitored. The shape and crystal orientation of the nanoparticles is reconstructed by scanning electron microscopy and electron tomography, which reveals that the nano-octahedra only selectively expose {101} facets at the external surfaces. The magnetic testing demonstrates that the Mn 3 O 4 nano-octahedra exhibit anomalous magnetic properties: the Mn 3 O 4 nano-octahedra around 150 nm show a similar Curie temperature and blocking temperature to Mn 3 O 4 nanoparticles with 10 nm size because of the vertical axis of [001] plane and the exposed {101} facets. With these Mn 3 O 4 nano-octahedra as a catalyst, the photodecomposition of rhodamine B is evaluated and it is found that the photodecomposition activity of Mn 3 O 4 nano-octahedra is much superior to that of commercial Mn 3 O 4 powders. The anomalous magnetic properties and high superior photodecomposition activity of well shaped Mn 3 O 4 nano-octahedra should be related to the special shape of the nanoparticles and the abundantly exposed {101} facets at the external surfaces. Therefore, the shape preference can largely broaden the application of the Mn 3 O 4 nano-octahedra.
This paper reports that the nanostructured β-FeSi2 bulk materials are prepared by a new synthesis process by combining melt spinning （MS） and subsequent spark plasma sintering （SPS）. It investigates the influence...
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This paper reports that the nanostructured β-FeSi2 bulk materials are prepared by a new synthesis process by combining melt spinning （MS） and subsequent spark plasma sintering （SPS）. It investigates the influence of linear speed of the rolling copper wheel, injection pressure and SPS regime on microstructure and phase composition of the rapidly solidified ribbons after MS and bulk production respectively, and discusses the effects of the microstructure on thermal transport properties. There are two crystalline phases （α-Fe2Si5 and ε-FeSi） in the rapidly solidified ribbons; the crystal grains become smaller when the cooling rate increases （the 20 nm minimum crystal of ε-FeSi is obtained）. Having been sintered for 1 min above 1123K and annealed for 5min at 923K, the single-phase nanostructured β- FeSi2 bulk materials with 200-500 nm grain size and 98% relative density are obtained. The microstructure of β-FeSi2 has great effect on thermal transport properties. With decreasing sintering temperature, the grain size decreases, the thermal conductivity of β-FeSi2 is reduced remarkably. The thermal conductivity of β-FeSi2 decreases notably （reduced 72% at room temperature） in comparison with the β-FeSi2 prepared by traditional casting method.
Ordered microporous carbon molecular sieves with high specific area and well-dispersed Pt nanoparticles have been prepared by chemical vapour deposition method. Electrochemical properties were measured, showing the ni...
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ISBN:
(纸本)9781424435432;9781424435449
Ordered microporous carbon molecular sieves with high specific area and well-dispersed Pt nanoparticles have been prepared by chemical vapour deposition method. Electrochemical properties were measured, showing the nitrogen-doped carbons exhibited excellent performance as an electrochemical supercapacitor.
Calcia stabilized zirconia（CSZ） ceramics were prepared with 7wt% calcia-stabilized zirconia powder by pressureless sintering technology. The crystal phases of the sintered samples were studied by X-ray diffraction（...
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Calcia stabilized zirconia（CSZ） ceramics were prepared with 7wt% calcia-stabilized zirconia powder by pressureless sintering technology. The crystal phases of the sintered samples were studied by X-ray diffraction（XRD） and Raman spectroscopy techniques, and the microstructures of the fracture surfaces were observed by scanning electron spectroscopy（SEM）. The phase compositions and the lattice parameters of cubic calcia-stabilized zirconia were calculated by XRD patterns. As the sintering temperature increasing from 1400℃ to 1600℃, the monoclinic zirconia content decreases gradually, finally all monoclinic phase transforms to cubic calcia-stabilized zirconia, which is deter- mined to be Ca0.134Zr0.866O1.866. It is revealed that monoclinic zirconia is the main factor causing minute cracks on the surface of sintered samples, and the combination of the XRD patterns and Raman spectra is an effective way to research the phase transformations of zirconia.
A stainless steel/10wt%TiC nanocomposite particles were prepared by high-energy ball-milling method using stainless steel, carbon and titanium as raw materials. The evolution of phase composition, microstructure and s...
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A stainless steel/10wt%TiC nanocomposite particles were prepared by high-energy ball-milling method using stainless steel, carbon and titanium as raw materials. The evolution of phase composition, microstructure and specific surface area of the stainless steel/TiC nanocomposite particles with increasing ball-milling time in the range of 0-100 h were investigated by XRD, SEM, TEM and BET techniques. The results showed that the stainless steel/TiC nano-composite particles were fabricated when the ball-milling time was longer than 20 h. However, the nanocomposite particles were soldered and agglomerated again when the ball-milling time was longer than 60 h. The microstructure of the composite particles transformed from lamellar structure to nanostructure during the repeated process of the cold welding and cracking. TEM image reveals clearly that the in-situ TiC nanoparticles with grain size of 3-8 nm are in the interior of the stainless steel/TiC nanocomposite particles obtained by ball-milling 100 h.
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