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In order to analyze dynamical strength reliability of mechanism, in taking the component section sizes, the material strength, the material density and acceleration of gravity as the random variables, and basing on the movement analysis and the dynamical analysis while taking the Assur-Group as the unit, the method of dynamical strength reliability analysis for the crank-rocker mechanism was established. The example was analyzed with using Monte Carlo (MC) method. The result indicates that computing speed of this method is high, precision of this method is high, and it has good universal property. It can be used in scientific research and the engineering practice.

Based on the parallelism of actual assembly sequence, a unified algorithm -"Optimal order reference set" is proposed for assembly performance membership degree calculation. An evaluation index system is established according to the requirements of practical assembly process. By using analytic hierarchy process for comprehensive evaluation of indexes, concrete application steps are verified through an example of a worm gear subassembly. Practical application shows that the new method satisfied the requirements of the integrity of index system and the parallelism of practical assembly sequence.

In this paper, the two main reasons are introduced such as great varying range of echo signal power and pulse signal error, which affect the pulse laser ranging accuracy and analyzed on the base of the pulsed laser range finding method. For them, the methods are provided that the AGC technology in the receiving circuit is adopt to extend the dynamic range of the receiver, and gain the high precision receiving pulse signal by using high-speed voltage comparator. Then the problems of great varying range of echo signals caused by different measuring distance and contacting the timing circuit are resolved efficiently.

This survey firstly reviews motion capture technology and the current challenge associated with the application in virtual human's control area. Secondly simplifies Jack's joint hierarchical model in order to drive Jack's virtual human to move by motion capture data. Thirdly uses Euler angle rotation equation to achieve pose mapping between BVH and Jack. Finally, results from experimentation show that when the motion capture data contained rich human motion details are retargeted to Jack by the paper's algorithms, the real-time interaction between virtual human and environment seems more real.

There are three levels in stability calculating for sway frame. The first level is the traditional effective length method. The second level is the effective length method considering interaction of columns in one story and the third level is the effective length method considering inter-story interaction. The traditional effective length method may lead to unsafe design. Using the concept of equivalent negative stiffness, story stiffness to negative stiffness ratio factor and story support factor were proposed. Through the story stiffness to negative stiffness ratio factor, the weak-story and the inter-story support relationship can be found. Then, a formula for calculating the elastic stability capacity of sway frame is proposed, by which the inter-column interaction and inter-story interaction can be considered, and the finite element buckling analysis for stability capacity can be avoided. Through the stability capacity, the column effective length can be calculated. The results show that this simple calculation method has good precision and accuracy, can be used for engineering design and theoretical calculations.

Experiment on bearing capacity of 24 Q460 high strength angle steel for compression members attached by one leg shows: the ultimate bearing capacity of the experiment value are higher than the calculated of the “Design of Latticed Steel Transmission Structures” (ASCE10-1997), on the same section in different slenderness ratio of components, the larger slenderness ratio, the higher the ratio; while on the same slenderness ratio in different sections, the greater width-thickness radio, the greater the ratio. Based on this problem, analyzing the current standard, a set of formulas based on high-strength angle struts connected by single Limb was brought, which can used for the design of the Q460 high-strength angle.

The steel roof of main palaestra of the World University Games is a long span space structure of single-layer fold face reticulated shells. The space positioning installation of members of this structure is very difficult, and the control accuracy is very high. In order to improving the installation accuracy of this space structure during the construction, a method named bulk-way assembly technology at high altitude with multi-points supporting had been adopted. After the closure of the steel roof structure the temporary supporting jigs began to be uploaded. During this process the supporting jigs quit work gradually and the main structure began to carry the load. Different uploading way will make different influence for the main structure and supporting jigs during the uploading process. These have to be considered in the structural design and construction stage. This article adopts construction mechanics and FEA method to analyze the uploading procedures according to the real construction process in order to finding the actual internal force and deformation and ensuring the security of the structure and supporting jigs. Lots of results have been obtained as guidelines in theory for the design and construction.

The effects of slow and rapid cooling methods on the postharvest physiology of Yali pears during ice temperature (-0.5°C) storage were investigated. Respiration rate, ethylene production, browning index and polyphenol oxidase(PPO) activity were used to evaluate the quality of Yali pears. The results showed that the slow cooling treatment decreased the levels of respiration rate，ethylene production，and PPO activity of Yali pears, and delayed the occurrence of the respiration, ethylene, and PPO activity peak compared to the rapid cooling treatment. The browning indexes of Yali pears with slow cooling treatment were lower than that of rapid cooling treatment. The results indicate that the cooling method may be an important factor affecting the storage quality of Yali pears. The slow cooling can delay the occurrence of physiological disorder during ice temperature storage.

Carbon nitride (CNx) films were fabricated by plasma enhanced chemical vapor deposition technology in methane-ammonia system, in which the plasma was excited by the hollow cathode glow discharge. The composition，microstructure and hardness of the deposited films were investigated by measurements employing X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and nano-indentation experiment. The results indicate that the nitrogen content in the film varies from 4.2 to 8.6 at.% and the nitrogen atoms are bonded to carbon atoms through C-N, C=N and C≡N bonds. Furthmore, higher nitrogen content is in favor of the formation of C-N bond, which may enhance the film hardness.

The problem of multi-level block reference is analyzed for the process of information extraction in engineering drawings. And the relationship of reference blocks has been established. By using depth-first algorithm, the multi-level reference path of blocks and the parameter transformation can be searched. Based on the algorithm, an arithmetic flow is proposed. And the method of coordinate transformation of reference blocks is expounded. The new method has important significance for comprehensiveness and accuracy of information automatic extraction of engineering drawings which contains multi-level reference blocks.

Based on theory of Lematire’s equivalent strain of the damage and with the damage of bars of the shallow reticulated spherical shell, on the basis of the nonlinear dynamical foundational equations and introducing dimensionless quantity of shells with uniform thickness, the nonlinear dynamic equation of the shallow spherical shells with initial damage were established by the method of quasi-shells. Then, the critical conditions of that chaos motion of the structure with initial damage are given by the Melnikov function. Finally, further using the digital simulation plotted the plane phase and it approved existence of the chaotic motion. It is found that the natural frequency of shallow reticulated spherical shells considering initial damage becomes bigger and the critical value of chaotic motion is smaller.

In the paper, the interface crack of rubber - metal ring under the radial displacement load was studied by nonlinear finite element method, changes of the tear energy with crack dimension which extending from extrusion end and tensile end along the axial and circumferential direction to the interface was analyzed. The result is that there is a certain possibility of axial extension in the tensile end. The crack propagation is most likely to occur along the circumferential direction while is impossible along either axial or the circumferential direction in the extrusion end.

We have theoretically discussed the resonance modes in a two-dimensional photonic multiple quantum wells structure (QWs) consists of one photonic crystal with square lattice of parallel dielectric circular columns in air and some layers of columns are removed at constant intervals. The generation and frequency split of resonance modes are observed and explained with tight-binding approach. The effect of the interaction distance on the frequency split is also discussed.

For the problem of determination of maintenance time in demonstration phase of materiel, analysis method based on maintenance concept and maintenance function is put forward. Maintenance concept gives the constraints for maintenance time By analysis of maintenance function, the relation between a function system of materiel and a maintenance level, and the relations of maintenance actions of levels are clarified. To describe determination of maintenance time for convenience, taking example for intermediate-level maintenance, on the basis of the given maintenance concept, models of maintenance time are built, and flow-processes of maintenance function are given. According to above analysis result, mean maintenance time of intermediate-level is determined. It provides an important basis for trading off the relation of impacting among maintenance concept, maintainability requirement, and design of materiel.

Nanocomposites were obtained by mixing elastomeric copolymer and nanoSiO2 in double-screw extruder at 130-150°C, in which the elastomeric copolymer was prepared by copolymerization of poly (methyl methacrylate (PMMA) macromonomer and butyl acrylate (BA) in benzene using azobisisobutyro-nitrile (AIBN) as initiator. The results indicated that increasing the amount of PMMA, the molecular weight of PMMA and copolymers, nanosilica charged resulted in improving the tensile strength and modulus at 300% elongation of nanocomposites, on the contrary, decreasing ultimate elongation and permanent set decrease. In additions, the tensile strength and the modulus at 300% elongation of nanocomposites reached to a maximum while the mass ratio of nanoSiO2 to copolymer was 3%.

Well-aligned crystalline ZnO nanorod arrays were synthesized on the glass substrate via an aqueous solution route, and the effect of the pH value on structural properties and morphology of ZnO nanorod arrays was investigated using XRD and FESEM. FESEM micrographs show the formation of ZnO nanorod arrays at different pH values. XRD patterns confirm that the ZnO nanorods were wurtzite structure preferentially oriented in c-axis direction and the highest quality of nanorod array was formed at high pH value.

Based on profound research of the characters on Petri Net, the concept of collaborative work heterogeneous data sharing (CWHDS) was proposed, and elaborated the modeling processes of CWHDS based on Petri Net. Furthermore, this paper used heterogeneous data queue to serve as the access station of CWHDS, and further discussed the translation and firing rule on Petri Net in relation to heterogeneous data queue. Finally, an application instance of multi-disciplinary collaborative design management system (MCDMS) based on CWHDS was introduced.

We show theoretically that the optical absorption of one-dimensional metallic photonic bandgap (MPBG) materials, which consist of alternating Ag and MgF2 layers, can be substantially enhanced by modifying the structure properly through decreasing the thickness of top MgF2 layer to half and increasing the thickness of bottom Ag layer to fivefold. Using transfer matrix method, absorption spectra and the electric field distribution profiles are numerically calculated. The absorption spectrum under reverse-direction incidence is also investigated. Based on strong and direction-dependent absorption properties, the proposed MPBG structure could allow many potential applications such as unique photothermal absorbing materials.

A series of poly(trimethylene terephthalate)/maleinized poly(octene-ethylene) copolymer blends are prepared and their melting, crystallization and dynamic mechanical propwerties were studied by using differential scanning calorimetry (DSC) and dynamic mechanical analyzer (DMA) respectively. The results suggest that the glass transition temperature of the blends shift to higher temperature because of the interaction between PTT and POE components. POE-MAH serves as a nucleating agent for the crystallization of PTT, and it increases the crystallizaiton rate of the blend and the start crystallizaiton temperature, but reduces the degree of crystallinity. Proper content of POE, e.g.1-2%, can improve the elastic modulus of the blend, but too much POE will depress the modulus.

Distribution network reconfiguration is a non-linear combinatorial optimization problem. It is defined as altering the topological structures of the power system by changing the open/closed states of the sectionalizing and tie switches.The aim is to reduce the power loss, and eliminate the overload of the lines, and improve the power quality, and restore the power supply to non-fault area in the distribution network and so on. Combined with distribution networks, The paper proposed an improved ant colony algorithm under the normal operating conditions to solve the distribution network reconfiguration problem. To demonstrate the validity and effectiveness of the proposed method, an example system is studied.The results on IEEE 71-bus distribution networks are also given,which reveal that the proposed method is feasible and effective.

Taking a group of SPSW with openings with or without edge members as example, this paper states the importance of edge members in view of initial stiffness, ultimate bearing capacity and ductility. First, FEM analysis is carried out to study the reasonable stiffness-range and it is found out when the inertia moments ratio varies from 6 to 8, edge members not only provide adequate anchorage, but also resist loads directly with main frame. Then, an unified calculation model called USMO is proposed, whose key point is to add inversed compression bars with stiffness to tension zone to simulate the increase of ultimate bearing capacity, leaving shearing part same to USM.

Displacement fundamental equations of the moderately thick cylindrical shallow shells concerning five independent variables, i.e. five middle surface displacements are established based on the displacement fundamental equations of the moderately thick shells by transverse shearing deformation and basic hypothesis on shallow shells. Three assistant displacement functions are introduced to solve the equations, which are tenth-order differential equations with variable coefficient; and then five second-order differential equations are converted into a second-order differential equation and two fourth-order transition differential equations using the Cauchy-Riemann condition, afterwards another assistant displacement function is introduced to build its decoupled governing differential equations, finally five displacement components through four assistant displacement functions are obtained.

Displacement fundamental equations of moderately thick shallow spherical shells in polar coordinates concerning five independent variables, i.e. five middle surface displacements are established, based on the displacement fundamental equations of the moderately thick shells by transverse shearing deformation and basic hypothesis on shallow shells. Four assistant displacement functions are introduced to solve displacement fundamental equations of circular moderately thick shallow spherical shells , which are tenth-order differential equations with variable coefficient, then the decoupled governing differential equations are built up, and five displacement components through four assistant displacement functions are obtained.

Based on the research of Life Ring in Shen Fu, the basic criteria for structural design of the unconventional rigid mega-structure linked with the ground are proposed in this paper. Through the structure comparison and selection, the space steel truss is used as the optimal structure form. After static analysis and time-history analysis by FEM, it is found that the control load case is the combination of dead weight and wind load. Because of its long vibration period, the structure is not sensitive during an earthquake. The key design of the structure is the selection of foundation form, a mixed-foundation made of steel trusses with piles is proposed in this paper. The steel truss is used as a bridge which transmits forces between superstructure and foundation. At last, the pile foundation is classified by the loading mechanism, the analysis and design of key joints in the mixed-foundation is proposed.

Because the repairing work of beam and floor after earthquake were great, and the cost were higher, the generalize application of eccentrically braced steel frame were limited. A new braced steel frame system was suggested, which was energy dissipating eccentrically brace. The experimental data of new and conventional D-type eccentrically braced steel frame system were achieved by two specimens under cyclic loading. Results indicated that the new system could put off yielding, reduce earthquake input energy and breakage of the link, reduce repairing load after earthquake, and have preferable ductility and enough lateral stiffness. The new braced steel frame system which had gained patent of invention in Chinese was practical and costly that it could be applied in present project.

Shape formation of post-tensioned and shaped hypar space truss is presented in this paper, the test space truss can be deformed into saddle shape by tensioning positive diagonal bottom layer strand. Nonlinear finite element analysis is applied in shape formation of space truss model. Based on both geometry and material nonlinearity, new FEM refering ‘tube to tube’ contact, is employed. Connector elements are used to simulate the bolt connection of the top joint, and the end of web. The results show that new method is relatively much more accurate than the previous way for the shaped size, and the theoretical values are consistent with experimental ones in stress and internal force distribution trend although the former ones are smaller, for FE model could not consider diagonal lower chord joining the structural system during shape formation.

A new kind of correction system with damp-increasing area-changing was analyzed and proposed through analyzing researches of one-dimension trajectory correction at home and abroad. And carried out an analysis of the change and the influence that caused by drag coefficient, lift coefficient with angle-of-attack and wind speed under different area. The mathematical model was proposed between increased drag coefficient and variable area opened by the damper. Feasibility and rationality of the new system were verified by simulation analysis. Furthermore, the damper can open at the right place under the system requirements. By researching aerodynamic characteristics of the projectile fixed this device would promoted the further design of damp-increasing range correction system.

The seismic performance of K-shape eccentrically frames were researched by cyclic loading test method, in order to understand earthquake performance, stiffness degradation and dissipation mechanism of energy. It can be concluded that K-shape eccentrically frames provide high elastic stiffness and demonstrate excellent energy dissipation capacity in the plastic stage, the different length of the link beam of different layers has great influence on the energy dissipation capacity of the structure, when shear yielding of link beam occurs, stiffness degradation become apparent, the hysteretic curves were plump in shapes. Therefore, K-shape eccentrically frames have better hysteretic behavior and energy dissipation capacity, the results can provide a reference for the engineering design and related research.

A new class of structural glue called permeant adhesive is introduced for repairing concrete cracks. The viscosity and strength of the permeant adhesive are tested, respectively. Then the durability of concrete such as sulphate attack, freeze-thaw resistance and impermeability of the repaired concrete are discussed. It is shown that temperature and reactive diluent are important factors in viscosity of the permeant adhesive. Curing agent and reactive diluent are important factors in strength. Hereby, the optimum proportion is A: B=1:0.5, and the amount of reactive diluent is 10% to 15%. The strength of the repaired concrete which is immersed in sulphate increases 3% to 26.2%, while the freeze-thaw resistance and impermeability of the repaired concrete are better. The above provide the theoretic and experiment foundation for simpling the pressure grouting technique of the concrete repaired and the application on the permeant adhesive.

To obtain a better understanding of the behavior and load-carrying capacity of Q460 high-strength single-angle compression members bolted by one leg, using static loading way to 48 angles carried out experimental study. The experiments show test specimens produce biaxial bending, most small slenderness ratio members are controlled by local buckling, and slender specimens are controlled by overall buckling. In addition to these factors in model experiment, influences of residual stresses on ultimate load-carrying capacity were analyzed by finite element numerical simulation analysis, the results show the residual stresses affect the ultimate load-carrying capacity of angles by about 5％ or less. Comparison of the load-carrying capacity of experimental and theoretical results indicate the difference of experimental and finite element values ranges from -9.99％ to +9.76％, American Design of Latticed Steel Transmission Structure (ASCE10-1997) and Chinese Code for Design of Steel Structures (GB50017-2003) underestimate separately the experimental load-carrying capacity by about 2.34％～33.93％ and 1.18％～63.3％, and the agreement is somewhat good between experimental program and the finite element analysis. Based on model experiment and simulated experiment, the formula of stability coefficient of single-angle compression members was established. It provides basic data for spreading Q460 high-strength single-angles members attached by one leg.

Based on the experiment of a one-third scale, single-span, two-storey semi-rigid composite steel frame model with cross-stiffened steel plate shear wall under lateral cyclic loadings, the interactive effect between the joint stiffness and the cross-stiffened steel plate shear wall, the failure mode and energy dissipation mechanism of the structure system were analyzed, some important parameters were obtained in regard to load-carrying capacity, ductility, stiffness and energy dissipation capacity. The results showed that the specimen exhibited excellent ductility, energy dissipation capacity and great safety margin; the stiffness degradation of the joints was not serious, the requirement of ductility was lowered by setting up infill panels, the cooperative work between the frame and the steel plate shear wall was well; stiffeners improved the force condition of steel panels, increased the stiffness and load-carrying capacity of panels, lightened the pinch of hysteretic loops and reduced the noise and tremor of panels. The failure mode of the structure induced by buckling of stiffeners, local buckling and interactive buckling of infill panels，plastic hinges were formed at the bottom of column and semi-rigid connection, the in-plane deformation of specimen was bending failure. The research provides a basis for engineering application and theoretical analysis of the structural system.

A second-order inelastic analysis of semirigid connection steel frame structures is developed. Therein, shearing deformation and axial force simultaneously are considered. A new stability function considered shearing deformation and axial force simultaneously is proposed and the analysis methods for steel structure of semirigid connection based on the structural ultimate bearing capacity are established. The calculatical programe of second-order inelastic analysis semirigid connection steel frame structures is compiled. The numerical examples of steel frames for semirigid connection are analysed using the second-order inelastic analysis in the paper. Load–displacements predicted by the proposed analysis compare well with those given by other approaches. The analysis results show that the proposed method is suitable for adoption in practice.

Poly(ethylene-octene)(POE) and organic montmorillonite(OMMT) acting respectively as the toughening agents and reinforcing agents, were used to prepare nanocomposites with Poly(trimethylene terephthalate)(PTT) in order to modify PTT, and the rheological properties of these composites were investigated by using capillary rheometer instrument. The OMMT used in composite was prepared by intercalating triphenyl phosphate (TPP) into MMT by mixed solution method. PTT/POE/OMMT nanocomposites were prepared by melt blending in twin-screw corotating extruder. Rheological results show that PTT/POE/OMMT composite melt was pseudo-plastic liquid and the pseudo-plasticity of the melt was decreased with increasing OMMT content for the strong interface interactions between OMMT and polymer molecular chains. The melt apparent viscosity was increased with increasing OMMT content. The flow activation energy results suggested that the composite melt having more OMMT components is more sensitive to the change of temperature.

The metal rubber is a kind of material for vibration control. In this paper, experimental research on characteristics of energy dissipation of metal rubber is exploited, and the relation between metal rubber stiffness and the amplitude of relative density and load. The relative between relative density and characteristics of energy dissipation is researched, in the excitation of displacement and load respectively. By comparing variation of the deformation and load with time, we found that the cycle of deformation and load is the same, but the deformation is still lag behind load. The research provided a basis for the application of metal rubber.

An ontology-based workflow (workflow-ontology) representation method was proposed after analyzing that not only structure information but also semantic information were needed in a workflow model. Workflow-ontology concepts were composed by class and subclass of the workflow. Concepts’ properties including their values and characteristics were redefined, and then, workflow-ontology modeling method was put forward based on the ontology expresses and definitions above. With the example of applying in products examined and approved workflows, the corresponding workflow-ontology model (WFO) was built.

One Micro-Electro-Mechanical System(MEMS) based actuator that fabricated by LIGA (Lithographie ,Galanoformung and Abformung) technology was designed to distinguish the change of the exterior condition. In order to prove whether the parts in the actuator intervene each other during motion, ADAMS software was utilized to simulate the motion. The rigid-flexible coupling dynamic modeling of the design was obtained by combining finite element method (FEM) with Lagrange equation, the mathematics modeling was solved with Gear method in ADAMS. The results showed that the MEMS-based actuator could move smoothly, and the simulated curve meets the intent.

A novel α-alumina-g-polyvinylpyrrolidone (α-Al2O3-g-PVP) composite abrasive was prepared by surface grafting polymerization. The chemical mechanical polishing (CMP) performances of the composite abrasive on hard disk substrate were investigated with a UNIPOL-1502 polishing machine. Analyses on the surface of polished substrate indicated that the α-Al2O3-g-PVP composite abrasive exhibited lower surface roughness, less scratch, and improved post-CMP cleaning performances than pure α-alumina abrasive under the same testing conditions.