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This study tests the antimicrobial properties of pineapple leaf fiber. Scanning electron microscopy (SEM), infrared analysis (IR) and other test methods were used to examine the microcosmic morphologies of pineapple leaf fiber. As the pineapple leaf fiber adhesive content reduce fiber antibacterial. Adhesive content 54% of fiber to escherichia coli and staphylococcus aureus antibacterial value is maximum. With further reduce fiber adhesive content, fiber antimicrobial declined obviously. The results indicate that the anaerobic bacteria can’t survive in the inside of pineapple leaf fiber where exist a large specific surface-area, lots of holes and Voids, and much oxygen. Pineapple leaf fiber contains a lot of phenols and their derivatives which are effective natural bacteria resistant materials and inhibit the metabolism and physiology of bacillus and other microorganism,break the structure of germ, and repress the generation of bacillus until the death of germ.Moreover, the existence of a small amount of cannabinol is adequate to kill the microorganisms.

Nonlinear characteristic hinder the effective use of piezoelectric smart materials in sensors and actuators. In this paper, the intelligent fuzzy PID controller is designed in the Matlab-Simulink environment. The piezoelectric smart actuator model is built. An adaptive fuzzy PID control scheme was proposed. The proposed control scheme was implemented in Matlab. The results of simulation and experiment indicate that the control method has good control ability.

Load modeling has become a critical problem that is urgent to be solved in power system modeling. In this paper, CQDPSO algorithm, a hybrid optimization algorithm that combines quantum delta-potential-well-based particle swarm optimization (QDPSO) algorithm and chaotic optimization algorithm (COA), is proposed to identify parameters of the selected load model. Numerical results illustrate that the proposed method can improve the accuracy and reduce the computation complexity for load model parameter identifications.

Urban passenger statistics is an important part of the social economic statistics, as an important part of urban passenger, the difference between supply and demand of taxi will directly impact the quality of residents' travel. The taxi passenger demand is forecasted according to the peoples travel conditions. The taximeter data survey method based on a fixed sample sampling and supplemented by the carpooling survey is put forward to determine the supply of taxi passenger. The difference between supply and demand of taxi passenger is analyzed. Accordingly, the result of the case analysis shows that analysis between supply and demand of taxi passenger provides strong support for government urban passenger management and control and be of great significance on theory and practice to the development of urban passenger transport industry.

Chitosan (CS) film prepared by casting-evaporation method, was processed by alkali leaching. Structural characterizations of CS film before and after alkali leaching were measured by Fourier transform infrared reflectance spectroscopy, X-ray diffraction. Effect of alkali leaching to thickness, mechanical properties, water contact angle, water-solubility and swelling index of CS film were investigated. The results manifested that CS acetate was converted to CS through alkali leaching. Vibration intensities of covalent bonds was decreased by alkali leaching. After alkali leaching, thickness, water-solubility and swelling index of CS film decreased, meanwhile tensile strength, elongation at break and water contact angle of CS film increased. Mechanical properties and waterproofness of CS film was improved by alkali leaching. The research results could provide theoretical basis for the application of CS film after alkali leaching.

Drop and pull transport is an efficient transportation mode. It brings considerable comprehensive economic benefit for companies, improves the transport efficiency and reduces carbon emissions quantity. In order to evaluate the performance comprehensively, the cost-benefit of environmental indicators are added to establish the comprehensive performance evaluation system of drop and pull transport on the basis of traditional financial evaluation index, the performance evaluation model with time value is also established. The comprehensive cost-benefit of drop and pull transport mode and traditional mode are analyzed by NAV and PVI. Accordingly, the result of the case analysis shows that drop and pull transport brings economic and green effects and has guiding significance to develop drop and pull transport.

Aiming at the advantages and disadvantages of triangle and rhombic main truss-types and their respective scopes of application, a comparative analysis for the two commonly used truss-type formtravellers has been done. The main factors for analysis are load bearing capability, structural rigidity, steel consumption and working space. It provides a useful reference for the design and selection of the formtraveller. In addition, for the overall deformation of the formtraveller, it is structural optimized while height of column of the truss and suspenders are changed. Finally, the analysis results show the reasonable height of the column and suspender arrangement to achieve the construction target of safety and cost-effectiveness.

Logistics center is a mordern logistic facility. The distribution center location determines the operational efficiency of logistics system. The optimum location of distribution center is important to transportation. In order to improved the algorithm's efficiency, elite strategy was introduced based on the standard immune algorithm. The improved algorithm avoid trapping into local optimal solution and solving the problem more slowly. The role of the elite strategy is to make the optimal solution attractively in the next cycle. This method sovles problem both quantitatively and qualitatively, which makes final solution better in accordance with practical demands.

This paper presents the tensile experiments of composite stiffened panel with three different stringer cut-out configurations. The strain distribution and delamination of the critical region near the stringer cut-out were studied. The influence from the different stringer cut-out configuration and geometric parameters on the strain distribution and delamination was evaluated via the comparison of experimental data, which can provide useful information to support further research and engineering applications.

As a typical cellular solid, the honeycomb core shows an orthotropic behavior in its mechanical properties. Engineering analysis often adopts a homogeneity assumption that honeycomb core is equivalent to an anisotropic continuum. Currently available cellular solid model cannot predict the physical properties of titanium honeycomb core with acceptable accuracy. Therefore, mechanical test must be carried out to obtain the mechanical properties of metallic honeycomb structures. This paper introduces the work on flatwise compression test and out-of-plane shear test on titanium honeycomb core structures in accordance to ASTM C 365-03and ASTM C 273-00. The out-of-plane stiffness and strength for titanium honeycomb cores with incircle diameter of 4.8mm and wall thickness of 0.05mm were obtained.

In accordance to ASTM test standards, this paper presents experimental studies on quasi-static indentation tests on sandwich panels with carbon fiber reinforced facesheet and foam core. The indentation force vs. displacement curves were obtained. A series of tests with different indentation depth were carried out to study the damage modes and damage propagation process of foam core sandwich panels under quasistatic indentation force.

The effect of weak interfacial orientation, thickness and the main crack depth on the initiation of delamination crack and main crack in three-point bending specimens of X80 pipeline steel are investigated, using 3D finite element method. Considering the different fracture mechanism of delamination crack and main crack, two different criteria are adopted for them in the simulation. The results reveal that, when the delamination cracks initiates, the initiating position is fixed and the Jz integral of the main crack is a constant for specific weak interfacial orientation specimens with different main crack depth and a certain thickness. When specific weak interfacial orientation specimens have different thickness and a certain main crack depth, the initiating position of delamination crack is equal to the above mentioned, but the Jz integral of the main crack has a ripad decline with the increasing of thickness and then tend to stable. In particular, the delamination crack will not appear for specimens with thin thickness. The thicker the specimen is, the higher the ultimate weak interface strength is needed to prevent the initiation of the delamination crack for specimen with a certain main crack depth. The larger delamination crack will generate, when the specimens have a lower ultimate weak interface strength, a smaller Jz integral of main crack and a larger thickness.

Structural and optical properties of MgxZn1-xO (x=0.23) thin films grown by radio frequency (R.F.) magnetron sputtering and annealed with different temperature (from 100°C to 400°C) are reported. The films were single-phase, highly c-axis oriented and wurtzite structure. The transmission spectra, recorded in the visible range, reveal a high transmission coefficient (about 95 %) in the obtained films. Besides, when the annealing temperature is 100°C, the crystalline grains are smooth, compact and uniformly distributed. As the annealing temperature increases from 100°C to 400°C, the crystalline grains get larger, but the annealing temperature does not influence optical transmittance obviously.

With continual scaling of ICs, the thickness of gate oxide becomes thinner and thinner which affects the reliability of semiconductor device greatly. The mechanism of time-dependent dielectric breakdown (TDDB) was analyzed. Six mathematical models of TDDB which were divided according to the position of defects and the physical property of charged particles were discussed. Then the dielectric breakdown characteristic of high k dielectrics and the relationships between the breakdown electric field, field acceleration parameter and dielectric constant were analyzed in detail. Finally, the relationships and mathematical models were verified by experimental data which provided theoretical basis for the choosing and use of high k materials.

Electrostatic discharge (ESD) is a single, fast, high current transfer of electrostatic charge between two objects at different electrostatic potentials, and it is one of the most important failure mechanisms in integrated circuits due to their complex operation condition. The modes, mechanism, and models of the ESD failure were discussed. Firstly failure modes of ESD were classified and the failure mechanisms were described. Then three failure models including Wunsch and Bell model, Speakman model and Tasca model were summarized. The differences of the assumption and application area of these models were discussed in detail later. At last, suggestions for future studying ESD physics of failure model were proposed.

Different from the reliability prediction method on handbook, the reliability prediction method based on Physics of Failure (PoF) model takes failure mechanism as theoretical basis, and combines the design in-formation with the environment stress of the product to predict the time to failure. When the uncertain of the parameters is considered to predict the reliability, Monte-Carlo calculation method is always used here. How-ever, the Monte-Carlo method needs large computational cost, especially for large and complicated electronic systems. A new reliability prediction method which combines the first order reliability with the reliability pre-diction method based on PoF model was proposed. The new method utilized the first order method to calculate the position of design point and reliability index, thus Monte-Carlo calculation process was avoided. Example calculation results showed that the new method improves the prediction efficiency without decreasing the accuracy of reliability, thus it is feasible for reliability prediction of electronic product in engineering.

CIGS thin films were prepared by selenization of Cu-In-Ga-Se precursors, as a new method, the effects of selenization temperature on the properties of CIGS thin films were studied. First, Cu-In-Ga-Se precursors were deposited onto Mo-coated soda lime glass by evaporation and sputtering method. Then, precursors were selenized at various temperatures in N2 atmosphere for 120 min to form CIGS thin films. The degree of reaction and morphology of films as a function of selenization temperature were analyzed. By means of field emission scanning electron microscope (SEM) and X-ray diffraction (XRD), it was found that CIGS thin films selenized at 450°C exhibit chalcopyrite phase with preferred orientation along the (112) plane.

The high-rise concrete residential market has been a gradually urban mainstream in recent years, and frame-shear wall structure is more used for high-rise residential structures now. This kind of structure has the advantage that the combination of frame and shear wall make the space free and flexible, and therefore the whole structure has considerable rigidity. The structure can not only satisfy the needs for people living in comfortable, but also has good dynamic and static load bearing capacity. This paper analyzed the mechanics characteristics of the structure and summarized the two kinds of main failure modes of shear wall and frame structure in earthquake. On this basis, the main principles are put forward to improve the seismic behavior of the shear wall. And further some of specific measures and suggestions which can improve the seismic performance for the frame-shear structure are introduced.

The tens of micrometers sized polystyrene(PS) microspheres were produced by dispersion polymerization in ethanol/H2O medium with poly(N-vinyl pyrrolidone) (PVP) as a dispersant and 2,2’-azobisisobutyronitrile(AIBN) as a radical initiator. The effects of PVP concentration and ethanol/H2O ratio on particle size and size distribution of PS microspheres were studied extensively. It was found that polystyrene microspheres with diameter 10-50μm were produced with 30wt% of St, 4wt% of AIBN, 3wt% of PVP and 97.5/2.5 ratio of ethanol/H2O, and narrow distribution of microspheres can be achieved by screening.

Response surface methodology (RSM) was used for statistical optimization of fermentation medium that influenced the yield of endo-polysaccharide from cultivated mycelia of Cordyceps militaris. First, the Plackett-Burman design was used to evaluate the effects of ten variables including glucose, maltose, peptone, yeast extract, KH2PO4, MgSO4, CaCl2, VB1, inoculum density and medium capacity. Among these variables, glucose, peptone and yeast extract were identified to have the significant effects. Subsequently, response surface methodology based on a five-level three-factor central composite design was employed to determine the maximum dry weight (DW) of mycelial biomass at optimum concentration of glucose, peptone and yeast extract. The mycelia growth was found to correlate to the three parameters that could be represented by second-order polynomial models. The optimal values of the three parameters were determined as 4.62% glucose, 3.36% peptone and 0.43% yeast extract. The prediction DW was 23.727g/L. The actual experimental results were in agreement with the prediction.

Masonry building with frame structure (hereinafter referred to as MBFS), rigid upper and flexible lower, is a special kind of structure appropriate for Chinese economic conditions in current years. Although this kind of structure is proven unstable in earthquake, its significant functional advantages and economic competitiveness make it popular in roadside buildings in small cities. In recent years, MBFS damaged seriously in earthquakes. This paper expounds different models and reasons of seismic damage of this kind of structures. This paper also discusses measures to reduce seismic damage of such structure. In the end, this paper proposes an ideal failure model of MBFS after analyzing the essence of damage. The ideals in this paper can help engineers reducing the seismic damage of MBFS as much as possible.

In this paper, we utilize Logarithmic Mean Divisia Index (LMDI) techniques to decompose different components —CO2 emission factor, industrial energy mix, industrial energy intensity, industrial-scale structure, industrial structure, economic activity, family size and family households—which contribute to the changes in CO2 emissions in Dalian industry sector based on industry economy and CO2 emissions data in Dalian from 2000 to 2009. The results show that the economic activity was the main component for CO2 emissions increase, and energy intensity was the most favorable component in developing low-carbon economy in Dalian industry sector, and optimize energy mix could contribute to a significant reduction in CO2 emissions.

Cadmium sulfide (CdS) thin films with (111) preferential orientation were grown on glass substrates at room temperature by radio frequency (R.F.) magnetron sputtering. The structural and optical properties of CdS films have been investigated by X-ray diffraction, Scanning Electron Microscope micrographs, PL spectra and transmittance spectra. The grain sizes have been evaluated. The transmission spectra of the obtained films reveal a relatively high transmission coefficient (80%) in the visible range. All these results show that the grain sizes increased while the optical band gap decreased with increasing the thickness of CdS films.

In order to research on the stress change and influencing factor of whole construction process of simply supported to Continuous system T-beam bridge, combined with Guizhou Bai-long bridge, the stress change is carried out the real time inspection in each construction stage, and the finite element model is established to analyse Stress changes in whole construction process. The monitoring value is ​​more consistent with the theoretical value in each stage , monitoring dates and theoretical calculations showed that pre-stressed is the main factor of stress changes in construction process.Pre-stressed tension in negative moment region has obvious influence on the stress of middle span, the stress of top and bottom plates in wet joints will be equivalent after tendons tension in negative moment Region.

Taking Tianjin Yonghe bridge for example, the finite element method is adopted to simulate each stages of cable replacement process, the dates of tension, the alignment of main beam and the change of stress before and after cable replacement are compared and analysed, The measured value is greatly consistent with calculated value, Stress state of the bridge has been greatly improved, the weight of main beam bearing by the cable will be shared by a few closed cable after unloading, so the cables which are more serious corroded should be replaced.

The steel - concrete composite structure has many advantages in the field of reinforcement of bridge. But it is an important factor that whether the stud connector can make the components be firmly combined and make them work together. The research in this area has been not enough depth. The purpose of this study is to establish the design formula of stud in composite structure. Based on the conversion section theory, the strengthened part of composite structure is simplified into a kind of structure which is composed by only one kind of equivalent material and its physical property is similar to the original. In addition, the simplified model is gotten by mechanical analysis of the composite structures with steel plate and stud. Then through the application of elasticity theory method, the static equilibrium is carried out on the integrated structure and so the shear capacity in stud of connectors is gotten.

Aimed at the problems such as welding stress concentration and especially irregular distribution of welding residual stress for anchorage area in cable-stayed bridges, three full-scale beam-anchor-plate connection models of Chongqing Jiangjin Guanyinyan Yangtse Rive bridge were made and the tests were performed. The purposes of the tests and study were to investigate the distribution of welding residual stress in anchorage area and moreover to find a way to reduce and eliminate the welding residual tensile stresses. For this reason ultrasonic impact was imposed on the main welds of the three models. The result of the experiment showed that there were quite considerable welding residual stresses in the anchorage area. It also displayed that the ultrasonic impact was able to effectively decrease and even release the welding residual tensile stress. The ultrasonic impact was able to not only improve the adverse state of the welds stress but also make the distribution of the welds stress smoother. The ultrasonic impact is an effective and feasible method to decrease and eliminate welding residual stress and thereby improve the fatigue strength of welds for the steel bridge.

In this paper, through the three-dimensional simulation of the cargo hold in the pre-cooling process–LNGC to reflect the changes of the cooling fluid at the internal space of the hold in pictures, which can directly and properly show the changes. In that case, it is of great practical and theoretical significance for us to master the Pre-cooling law, increase the Pre-cooling rate and the management of LNGC in the future.

In this paper, double embedded elliptical cracks in a weld of pressure vessels under tension was taken into consideration, and stress intensity factors at the crack tip were calculated with the emphasis on the interaction between cracks. It is found that when the distance between the double embedded elliptical cracks is larger than the major semi-axis of the ellipse, influence between the cracks can be neglected. Unlike the single embedded crack, owing to the crack interactions, the point with maximum stress intensity factor is not always at the end of the minor axis of the ellipse, it may swift to the end of major axis, especially when the ellipse is close to a circle.

This paper presents the test of ultrasonic impact for reducing the welding residual stress. Three full-scale specimens according to the anchor connection plate of main girder with cable of the Jiangjin Yangtze River Bridge are made and the ultrasonic impact test are taken in laboratory to study the effectiveness of reducing welding residual stress. The comparison of welding residual stress before ultrasonic impact with the stress after ultrasonic impact is conducted and the results from test show that the welding residual stress can significantly be reduced over 50% by ultrasonic impact method and even some stress in weld could be changed form tensile stress into compressive stress after ultrasonic impact.

With people's increasing awareness of safety and health, the demands of protective clothing for electromagnetic radiation are gradually increased. The influences of clothing structural factors on protective performance for electromagnetic radiation are studied in this paper. The shielding effectiveness (SE) of fabrics has been tested according to the SJ20524-1995 standard. Meanwhile, according to the measured conditions of fabrics, a simulation model of testing fabric is established by the three-dimensional electromagnetic simulation software Ansoft HFSS to simulate the influences of clothing structural factors on the electromagnetic protective performance under the irradiation of electromagnetic waves at different frequencies. The impact of the length of clothing seams, the size and shape of clothing openings, and the change of clothing layers on the electromagnetic protective performance have been simulated and analyzed in detail. The results show that the simulation results are basically identical with the actual measurement results, and the model of testing fabrics can be applied for the researches on the protective performance for electromagnetic radiation. The study also shows that both seams and openings of clothing will reduce the shielding ability of clothing to electromagnetic radiation, and the change of clothing layers also affects the electromagnetic protective performance of clothing greatly. The results of this article can provide references for the design of electromagnetic shielding clothing, and effectively reduce the adverse effects of clothing structural factors on the protective performance of clothing.

Nowadays the market of fashion luxury is expended in China. Foreign luxury brands have been landing in China in succession and the fashion luxury as an important part of luxury products has also showed a prosperity market. By using of brand theory, the definitions of luxuries and fashion luxuries are given to analyze the characters of fashion luxuries under the premise of a profound understanding of meaning and role of the brand. The approaches of qualitative are used in combination in this article. The qualitative approach is applied to analyze the market of luxuries in China, the consumers’ behaviors and the consumers’ psychology. The interview methods are adopted to collect information. The elements of fashion luxuries and the indicators for physical and psychological are analyzed and proposed. On the basis of above researches, the marketing strategies for the development of domestic fashion luxury are raised up. Main points are given in this paper can be applied as a foundation of the fashion luxury market development. It makes helpful suggestions for native luxury brands’ designing and for marketing strategy’s planning. It is hopeful to provide practical ideas and methods for administrators of fashion luxury brands’ management and operation.

The fibular PANI/ nano-CeO2 composites were synthesized via chemical oxidation of aniline using nano-CeO2 as an oxidant, and nano-CeO2 was prepared by hydrothermal treatment. Sphere-like morphology and fibers of PANI/ nano-CeO2 composites were obtained. The resulting composites were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Fourier transform infrared (FT-IR). The results showed that chemical bonds existed between two phases. The acid concentration and nano-CeO2 particles affected the crystallinity of PANI fibers. The morphology of PANI was formed from the ball gradually developing into the fibular with rising of acid concentration. The regular crystalline structure of fibular was easy to form with a reducing CeO2 particle size.