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The Internet can break through the limitations of time and space, and provide more possibilities for education in the context of the world's popular situation. In this article, the author uses big data to analyze the national scholarship evaluation criteria and the experience of ESE scholarship winners in recent years, combined with the core development literacy of Chinese students proposed in 2014, the author build on the basis of independent development and social participation Get up, take independent study, participate in management, practice, and undertake the four major achievements as the framework to realize the establishment of the theoretical model of the ability and literacy of the national scholarship recipients of the "double first-class" university. Through the construction of the model, it can provide corresponding practical ways for the cultivation of university talents.

The process optimization of train operation is a sophisticated multi-objective optimization problem, especially in the condition of timing constraints. Due to the fact that the multi-objective optimization model of train operation process with time constraint is difficult to be solved precisely in the limited optimization time, the process optimization of train operation with time constraint based on multi-objective memetic algorithm (MMA) is proposed by using weight adaptive particle swarm optimization (PSO) and fuzzy logic in this paper. In order to enhance the global searching performance of the proposed algorithm, based on the analysis of the influence of inertia weight PSO global convergence, an improved PSO is presented to obtain the better optimization results. The shortcoming of the conventional PSO can be improved by optimizing the inertia weight and the evolution algebra relation curve. Meanwhile, for accurately obtaining a better solution in the neighborhood of the solution, a local search algorithm is developed by using a fuzzy decision based on the fuzzy logic of driving experience. The advantages of the proposed method are summarized as follows: Firstly, a better convergence effect can be obtained by the global search algorithm. Secondly, by combining the fuzzy logic of driving experience and the fuzzy decision, the local optimization effect can be improved. Finally, simulation results are provided to show the efficacy of the proposed method.

Ba 0.4 Sr 0.6 TiO 3 (BST) thin films were prepared by spin-coating technique and deposited on either Pt/TiO 2 /SiO 2 /Si (Pt/Si) substrate or silicon buffered by a lanthanum nickel oxide buffer layer (LNO/Si). X-ray diffraction and scanning electron microscopy showed that the BST films were crack free, compact and crystallized with a single perovskite structure. The effects of bottom electrodes on dielectric properties and energy storage performance of BST films were investigated. The results shows that the dielectric constant of BST/Pt film is a little higher than that of BST/LNO film, and the dielectric loss at 1 kHz of both films is very low

Sr(Nb 0.5 Al 0.5 ) x Ti 1−x O 3 (x=0, 0.02, 0.04, 0.06) ceramics were obtained via solid-state reaction method and sintering in air at 1540°C. The grain size of SrTiO 3 ceramics decreased with Nb 2 O 5 and Al 2 O 3 doping content. Sr(Nb 0.5 Al 0.5 ) x Ti 1−x O 3 ceramics exhibit a giant permittivity of about 10500 and low dielectric loss of 0.03 measured at room temperature and 1kHz. According to the XRD, XPS, and ac conductivity analysis, this excellent dielectric behaviors of Sr(Nb 0.5 Al 0.5 ) x Ti 1−x O 3 ceramics would originate the bond[Ti4+·e-V O ‥-Ti4+·e], in which the electrons were bound by Ti4+ and V O ‥ leading to low dielectric loss. Compared with SrNb 0.01 Ti 0.99 O 3 and In addition, SNAT ceramics were also sintered in oxygen atmosphere and nitrogen atmosphere to verify the existence of [Ti4+·e-V O ‥-Ti4+·e].

Linear dielectric materials are ideal options for energy storage application due to the typical high energy storage efficiency and breakdown strength. In the present work, pore free Ca 0.6 Sr 0.4 TiO 3 (CST) ceramics with various amounts of Mn dopants (0%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 1.0%, 1.5%, 2.0%) were prepared via solid state reaction method. P-E curves were measured under a temperature range of 25∼150 °C. Energy storage densities and efficiencies were calculated and found to be greatly enhanced for CST with moderate Mn dopants, to be specific, 0.5% Mn demonstrated the optimized high temperature energy storage properties. The conduction relaxation behavior was investigated and the conduction activation energy was found to be sensitive to the variation of energy storage properties.

Feature representation is one of the key research issues in machine learning. In some applications with high dimensionality of data, e.g. genomie microarray data, obtaining a good feature representation with effective dimensionality reduction still remains a challenge. In this paper, instead of selecting a subset of original features by feature selection, we use sparse autoencoder to find a reconstructed feature representation for genetic data analysis. The performance of our proposed method is empirically evaluated using one of the genomie microarray dataset provided in ASU Feature Selection Repository. The results show that the proposed method yield better classification accuracy than some representative feature selection methods.

Bi 2 O 3 doped BaTiO 3 -(Na 1/4 Bi 3/4 )(Mg 1/4 Ti 3/4 )O 3 (BT-NBMT) polycrystalline ceramics were prepared by solid state reaction method. The effects of Bi 2 O 3 additive on the microstructure and dielectric properties of BT-NBMT ceramics were investigated. The Bi 2 O 3 effectively lowered the sintering temperature and improved the bulk density of BT-NBMT ceramics. The low-temperature stability first improved and then deteriorated with increasing Bi 2 O 3 concentration. The core-shell microstructure undertook responsibility for the good dielectric temperature stability. The dielectric ceramic samples with good permittivity and low dielectric loss were obtained at a moderated sintering temperature. The results also suggest that the developed BT-NBMT ceramics may serve as a promising candidate for multilayer ceramic capacitors.

The phase structure, microstructure, dielectric and energy storage properties of 0.85(0.92Bi 0.5 Na 0.5 TiO 3 -0.08BaTiO 3 )-0.15(Na 1−3x Bi x NbO 3 ) (BNTBT-NB x N) polycrystalline lead-free ceramics were systematically investigated. Dense and pore-free samples were prepared by conventional solid state reaction method. X-ray diffraction results indicated that the solid solubility of Bi in BNTBT-NB x N system lay at x=0.05∼0.07. Within the solid solubility, the first dielectric anomaly which located at temperature T s was depressed and shifted towards lower temperature with x increasing. As a consequence, the temperature stability of dielectric properties was largely improved, which demonstrated that BNTBT-NB x N ceramics were promising for high-temperature capacitor dielectrics. The ferroelectric properties analysis indicated that with the increase of x, the maximum polarization P m gradually reduced and the P-E loops became slant and slim. The optimum energy storage properties was obtained for x=0.05 with energy storage density W=1.29J/cm3 and energy storage efficiency η=76%.

Linear dielectric materials are ideal options for energy storage application due to the typical high energy storage efficiency and breakdown strength. In the present work, linear dielectric system Ca 1−x Sr x TiO 3 (x=0∼0.6) was synthesized through conventional solid state reaction method. All the samples were sintered at 1400oC and had dense and pore-free microstructures. The effects of Sr substitution on the phase transition, microstructure and ferroelectric properties were systematically investigated. Slow scanning X-ray diffraction showed that crossover region between orthorhombic phase (Pbnm) and tetragonal phase (I4/mcm) at about x=0.30–0.50 has been obtained. SEM revealed the Ca 0.6 Sr 0.4 TiO 3 ceramics exhibit the most homogeneous microstructure with fine grains. The breakdown strengths were found to be enhanced near the phase transition composition due to the optimized microstructure, Ca 0.6 Sr 0.4 TiO 3 showed the highest breakdown strength, which reached 26 kV/mm at room temperature. Additionally, HfO 2 , with a high band energy, was selected as additive into the Ca 0.6 Sr 0.4 TiO 3 system to mitigate the high-temperature and high-field loss, so that to improve the stability of energy storage efficiency under elevated temperature and electric field.

(Ba 0.4 Sr 0.6 )TiO 3 (BST) paraelectric ceramics (T c ≈ −67 °C) with various grain sizes (0.6–1.8 μm) were synthesized by oxalate co-precipitation method and prepared by conventional solid-state sintering process. With decreasing grain sizes, the dielectric breakdown strength increases gradually. Based on the conductivity activation energy analysis, it was found that the larger grain boundary density plays a dominant role in controlling dielectric breakdown strength for samples with smaller grain sizes (1.0 to 0.6 μm). While with the growth of grain sizes above 1.0 μm, the sharply decreasing dielectric breakdown strength is induced by a combined effect of lower grain boundary density and more intensive interface polarization.

A modified polymer-network gel route has been developed to prepare a multilayer core-shell structure of BaTiO 3 -based dielectric ceramics, which greatly improved the efficiency of gelation process. The core particles are BaTiO 3 , while 0.7 BaTiO 3 -0.3Bi(Zn 1/2 Ti 1/2 )O 3 (0.7 BT-0.3BZT) and Nb oxides were coated in order as the shell material. The influences of core-shell structure and ratios on the dielectric properties were studied. The samples of coated BaTiO 3 were found to possess optimized temperature stability of dielectric behavior in the temperature range of −55 to 200°C (ΔC/C≤ ± 15%), the dielectric constant at room temperature could reach 1190, with a low dielectric loss at about 1.3%.

BaTiO 3 -based MLCC materials were limited for high temperature applications (temperature range up to 200°C), due to their low Curie temperatures. The addition of Na 0.5 Bi 0.5 TiO 3 (NBT) component in BaTiO 3 (BT) based ceramics was found to increase the Curie temperature, without sacrificing the dielectric constant. The Curie temperature was reported to increase from 125°C to 156°C with addition up to 10mol%, making it possible to satisfy the X8R or X9R criterions. In addition, the small amount of Nb 2 O 5 dopant in the system leads to a diffused dielectric maxima and improved temperature stability. The NBT-BT with 2wt% Nb 2 O 5 addition was found to exhibit a core-shell structure, while maintaining the dielectric constant at about 2500. To analyze the electrical microstructure variation, the obtained impedance data was fitted by a 4RC equivalent circuit, corresponding to the core, shell, grain boundary, and ceramic/electrode interface regions. All the electrical properties, including the capacitance, activation energy, and conductivity could be well explained by using this equivalent circuit.

Surrogate modelling based optimization algorithms have been regarded as a powerful tool for solving expensive-to-evaluate functions, and numerous successful applications on optimization problems from various fields have been reported in literature. However, little effort has been devoted to solve complex combinatorial optimization problems through surrogate modelling, since evaluation for solutions of these problems is computationally cheap in general sense. In this paper, we firstly propose a two-layered decomposition of bottleneck stage scheduling problem, in which the subproblem of upper layer can be regarded as an expensive-to-evaluate problem, and the subproblem of lower layer is comparatively easy to solve. Then, we present a differential evolution algorithm combined with a surrogate model to solve the upper-layer subproblem, and the lower-layer subproblem is solved by an effective brand and bound algorithm. Considering that simulation data is generated in a continuous manner, we adopt an incremental extreme learning machine as the surrogate model to reduce the computational cost while preserving good generalization performance. Computational experiments demonstrate the effectiveness and efficiency of the proposed hybrid approach.

The interfacial reaction in Cu/Sn/Cu fine pitch interconnects during soldering at 250 °C was investigated in the present work. The morphological evolution and growth kinetics of the interfacial intermetallic compounds (IMCs) were studied. Cu6Sn5 scallops formed at the Sn/Cu interface and ripened with increasing reaction time. The dependence of average grain number on reaction time t followed t-0.70 relationship. During the solid-liquid interfacial reaction, different growth behavior of interfacial Cu6Sn5 scallops presented between the direction vertical to the interface and that parallel to the interface. According to the ratio of R/H, the growth of interfacial Cu6Sn5 could be divided into three stages, i.e., the initial stage, the ripening stage and the thickening stage. The growth of Cu6Sn5 scallops was controlled by grain boundary diffusion, while that of Cu3Sn was controlled by volume diffusion.

In this paper, zinc borosilicate glasses (ZnO-B 2 O 3 -SiO 2 ) were added to Ba 0.3 Sr 0.7 TiO 3 (BST) ceramics, to determine the role of glass additives on the dielectric properties and energy storage density of BST. Microstructure, relative density, dielectric properties and the breakdown strength (BDS) were investigated. The dependence of permittivity and BDS on the glass composition were discussed. The results indicate that the relative density of BST ceramics with glass additions can be greatly improved because of the glass liquid phase formation during sintering. The BDS was found to increase remarkably by sacrificing the dielectric permittivity. The BST ceramics with 6 wt% ZBS3(40mol%ZnO-35mol%B 2 O 3 −25mol%SiO 2 ) glass were found to possess optimal properties, with BDS∼26.7 kV/mm and energy density∼1.5 J cm−3.

Bismuth strontium titanate ceramics are rarely used for energy storage. In this paper, the energy storage characteristics of bismuth strontium titanate ceramics (1-(x/3))SrTiO 3 -(x/3)(Bi 2 O 3 •3TiO 2 ) were systematically researched. The traditional solid phase sintering method was employed for preparing bismuth strontium titanate ceramics. The frequency dependence of dielectric constant, the frequency dependence of the dielectric loss, and the DC electric field dependence of dielectric constant were measured. The energy storage density was obtained by integrating the area within the polarization axis and the discharge curve in the polarization-electric field (P-E) curve. Experimental results show that, when x=0.15, (1-(x/3))SrTiO 3 -(x/3)(Bi 2 O 3 •3TiO 2 ) ceramic has high dielectric constant, fine frequency stability, high resistivity, low dielectric loss and weak DC electric field dependence of dielectric constant. And its energy storage density could achieve 1.63 J/cm3 at 217.6 kV/cm electric field. Thus, it may possess the potential being used as a kind of energy storage dielectric material.

(1−x)Ba 0.67 Sr 0.33 TiO 3 (BST)+xCaBi 4 Ti 4 O 15 (CBT) (x=0, 2%, 4%, 6% and 8%) lead-free relaxor ferroelectric ceramics with submicro grain size of about 200nm were prepared by solidstate reactions. Structure and dielectric properties of BST-CBT have been investigated. X-ray diffraction patterns show a relative low degree of solubility as a result of coupled substitutions of Bi3+ and Ca2+ both on the A site and the specific structure of CBT. The temperature and frequency dependences of the dielectric constant indicate a crossover from a normal ferroelectric to relaxor behavior. The degrees of diffuseness and relaxor behavior are found to increase with the increasing amount of CBT. The frequency dependence of the temperature of dielectric peak Tm can be well described by Vogel-Fulcher relation. The activation energy Ea increases with x increasing, indicating the more and more energy for the polarization reversal of micropolar regions, which is associated with the enhanced interactions of polar domains.

The development in ICT over the past century have accelerated spectacularly in the past few decades. This has opened a new way forward for innovation and productivity improvement in services via their impact on organization and coordination. Innovation in services has received a great boost recently from new ICT and accompanying market evolution. This is more than just an outward shift in the production function, but rather the evolution of economic coordination through increasing division of labor. In this paper, we propose a theory of this evolutionary process.

Lead free textured K 0.5 Na 0.5 NbO 3 piezoelectric ceramics have been prepared by reactive-templated grain growth method by using NaNbO 3 with different morphologies as templates. The NaNbO 3 template particles with different edge length (10–20 µm) and thickness (0.5–2.5 µm) was synthesized through controlling Bi 1.5 Na x−1.5 Nb x O 3x+3 precursor's layer numbers x from 2 to 6 by two-step molten salt methods. The crystalline phases and microstructure of textured K 0.5 Na 0.5 NbO 3 were characterized by X-ray diffraction and scanning electron microscopy, respectively. It shows that all the K 0.5 Na 0.5 NbO 3 ceramics are orthorhombic perovskite structure with {0 0 1} orientation. By using the template particles with a ratio of edge length to thickness (l/h) =∼10, the textured ceramics with optimized piezoelectric properties was prepared. The results indicate that the enhanced properties of textured ceramics are concerned with the template morphology.

In the present study, (1−x)(Sr 0.88 Bi 0.08 )TiO 3 -xBi(Mg 0.5 Ti 0.5 )O 3 (SBT-BMT) system was synthesized using conventional solid state processing. X-ray diffraction (XRD) and SEM testings were employed to determine the phase constitution and microstructure of ceramics. SBT-BMT ceramics exhibited moderate dielectric permittivities (e r ) (>1100 at RT) and low dielectric loss (0.07%) over the temperature range from −20 to 200°C, with flat temperature coefficients of permittivity. In addition, SBT-BMT ceramics were observed to possess dielectric relaxation characteristics and energy densities, being on the order of 1.4 J/cm3 at 180 kV/cm was observed for the 0.8S 0.88 B 0.08 T-0.2BMT ceramics.

The hypercrosslinked polystyrene adsorbents of LY-4 and LY-5 were prepared By Friedel-Crafts post-crosslinking reaction with phenol and naphtho. The physical properties of absorbents showed that both phenolic hydroxyl group content and BET surface area of LM-5 are higher than LM-4. Accordingto the adsorption experiment in aqueous solution, the adsorption capacity of aniline onto LM-5 is bigger than that of phenol. The adsorption enthalpies of ΔH for adsorption of phenol (aniline) onto LM-5 are all negative and their absolute values are lower than 40 kJ/mol, which indicate that the adsorption is exothermic process and the physical adsorption is dominant in the adsorption process. Both The Gibbs free energy change of ΔG and adsorption entropy change ΔS of the adsorption are also less than zero which demonstrates that the adsorption is a spontaneous process. The absolute values of ΔH, ΔG and ΔS for adsorption of aniline onto LM-5 is bigger than that of phenol.

Tolerating double faults is an important issue for diskless checkpointing due to the size and increase of the executing time. This is why Mutual-Aid checkpointing has become the first scheme to achieve the goal. Mutual-aid checkpointing combines the advantages of neighbor-based, with parity-based diskless approaches. This also tolerates all double processor faults by bitwising exclusive-or snapshots from its neighbor processors in its virtual assistant ring. In view of the fact that checkpointing and recovery of mutual-aid are so simple and efficient, this increases the performance, reduces application running time, and allows more frequent checkpoints. Moreover, it could be employed towards a very largescale and high performance computing field because of its distributed methods as well as localized operations. The degree of fault tolerance has achieved higher success than other schemes.

The delay-dependent robust H infin control problem for a class of nonlinear time-delay system is investigated in this paper. An uncertain Takagi-Sugeno (T-S) fuzzy model is adopted for representing a nonlinear system with time-varying delay, in which the modeling errors are absorbed in the uncertain part. The design method of delay-dependent robust H infin controller is firstly established via the parallel distributed compensation (PDC) technique. Meanwhile, a stabilization method is developed in terms of linear matrix inequalities (LMIs). Two examples are provided to prove the effectiveness of the present results.

3D stacking and integration can provide system advantages equivalent to up to two technology nodes of scaling. This paper explores application drivers and computer aided design (CAD) for 3D ICs.