Abstract:The results of an experimental research involving the testing of four moment-resisting connections under antisymmetric loads at the cantilever ends of beam were presented. The test specimens modeled the interior joint of a moment-resisting frame consisting of concrete-filled double skin tubular column and steel beams with reinforced concrete slab using high-strength bolts and T-stub connectors. And the typical failure modes and shear-deformation skeleton curves were evaluated. Based on the experimental results, the force mechanism and the total process of shear performance on the panel zone were analyzed. Three trilinear shear-deformation relationship models for the web of steel tube, the flange of steel tube and the concrete core were proposed. By simplifying and adding these three models together in the condition of consistent shear deformation, the calculation formulas of the yield and ultimate shear strength of the joints were established. The formulas were used to calculate the shear strength of the panel zone of four joints, and the results calculated with the proposed formulas agreed well with those of the tests.

Abstract:The calculation methods of the overall stability of I-section steel beams, under loading both on upper and lower flanges, are not contained in current steel structure code. Energy method was used to derive the critical moment formula of biaxial symmetry I-beams under the loading mentioned above, and the effects of the load scale factor on the critical moment were also summarized. The finite element method was used to verify the moment formula. The results of the finite-element calculation were consistent with the theoretical results when the load scale factor was less than 3. In addition, through computational analysis, the formula of the equivalent critical bending moment coefficient for the I-section steel beams under the same loading was put forward. This formula has a preferable calculation accuracy.

Abstract:In order to study the compressive properties of reactive powder concrete (RPC) at elevated temperature, 108 cube specimens (70.7 mm×70.7 mm×70.7 mm) were prepared to study the group compressive strength of RPC with polypropylene fibers (PPF) and steel fibers. The influences of temperatures, hybrid fibers content and explosive spalling principles were investigated. The experiment results show that a PPF volume content of 0.2% and a steel fiber volume content of 2% can prevent the explosive spalling of RPC and significantly increase cube compressive strength. The cube compressive strength decreased at 100℃, compared to 20℃ and increased from 200℃ to 500℃ as compared to 100℃, but decreased after 600℃. The cube compressive strength of RPC was lower as the fibers content increased before 300℃, but was higher as fibers content increased beyond 300℃ when steel fibers was the same content. Cube compressive strength of RPC was higher as the steel fibers content increased before 100℃, but was lower as steel fibers content increased beyond 200℃ when PPF was the same content. Compared with the normal strength concrete and high strength concrete, the cube relative compressive strength of RPC was lower before 400℃, but was higher between 500℃ and 800℃. The calculation formula of cube compressive strength at elevated temperature was obtained by fitting the curve of experiment data considering hybrid fibers content as temperature varied.

Abstract:Combining with the advantages of evolutionary spectra theory and orthogonal HHT method, a method for the simulation of ground motions was established, which could simulate both non-stationary strength and frequency. Two harmonic-like long-period seismic records from Chi-chi Earthquake in Taiwan 1999 were selected as the original sample to simulate the long-period ground motions. The orthogonal HHT method was adopted to study the local spectral density and energy distribution of the artificial harmonic-like long-period ground motion samples. It was shown that the artificial ground motion samples obtained in the proposed method had an agreement in energy-time-frequency distribution with the original ground motions. It also has a good performance in the compatibility of elastic and elastic-plastic response spectra. The artificial harmonic-like long-period ground motions obtained in the proposed method can be used in the seismic response analysis of engineering structures.

Abstract:Specimens of cold-formed steel quadruple limbs built-up box section member were tested to investigate its load capacity under flexural loading, and a finite element model involving geometric large deformation, materials and contact nonlinearity was established for numerical analysis. The model was validated by comparing the failure mode, ultimate bearing capacity and load-deflection curves with the test result. Based on this proved model, a series of parametric analysis was carried out to identify factors affecting flexural strength, such as spacing of screws, the height and width of section, and the quantity of initial imperfections. A practical design method named reduction coefficient method based on effective width method was proposed and compared with current AISI and Chinese cold-formed steel codes. It shows that current AISI and Chinese codes lead to a conservative evaluation. The reduction coefficient method proposed in this paper shows good agreement with the finite element result, and is relatively simple and convenient for design.

Abstract:First of all, the Rapid Innovation Model was established on the basis of the traditional technological innovation, and this model contain four parts and nine steps: definition of problem, basic reason analysis, goal determination, functional model analysis, evaluation of scheme, experiment method, evaluation of effect, and summary and application. Secondly, this paper introduced the process of SPIP Method which contains three parts: interpreting the problem according to the basic reason, seeking the answer with patent analysis and construction model, and getting the solution in TRIZ and invention principle. In a word, the rapid innovation model can meet the speed and quality of construction model development, and it points out a new way of developing construction models.

Abstract:The dynamic fracture problem under an impulsive load was analyzed using the meshless local Petrov-Galerkin method. The moving least squares (MLS) approximation was adopted to approximate displacement functions, and the penalty function method was used to impose the displacement boundary conditions. The Newmark method was applied in the time integration scheme. The stress fields near the crack tip of a double notched plate and time histories of dynamic stress intensity factors (DSIF) for mode-I and mode-II were obtained. The numerical example shows that the local Petrov-Galerkin method is feasible and effective to analyze the dynamic fracture problem under the impulsive load, and has advantages of higher precision, higher efficiency and easy implementation.

Abstract:In order to support the maximal protection of 6-year-old children passengers based on a new integrated child safety seat which has been patented, the new integrated child restraint system parameters were optimized. And this child restraint system model has been verified. The Latin Hypercube, Orthogonal, Uniform test design and Response Surface Model method were performed to optimize and design the parameters of seat height, seat cushion depth and so on in frontal, side and rear crashes. The results indicate that the optimized injury values decrease obviously in three independent crash cases.

Abstract:To solve the structural reliability of the implicit nonlinear performance function (PF) that is complicated and changeable in the non-normal variable space, the advantages of the saddle-point approximation (SA) and line sampling (LS) were merged, and the merits of dichotomy and the solution efficiency of the golden section method were combined to propose the saddle-point approximation-line sampling (SA-LS) method based on the dichotomy of the golden section point. According to SA, it is quick to find the zero-point in PF corresponding to each sample along the important LS direction by the above dichotomy so that the structural failure probability can be transformed into the arithmetical mean of a series linear PF failure probability. This research shows that the SA-LS method based on the dichotomy of the golden section point is of high precision and fast velocity when it is used to analyze the structural reliability for implicit nonlinear PF, which are complicated, changeable and of non-normal variables.

Abstract:In order to study the composite load modeling of distribution network with microturbine generation (MTG) system, the grid-connected MTG system was established. The third-order differential equation of state description equivalent model of MTG system was presented, and the validity of this equivalent description model was verified. Based on these, the model structure of the generalized load model of distribution network with MTG system could be described as traditional synthesis load model paralleled with MTG equivalent description model. The model validation was testified by the simulation modeling of different disturbance levels and different load levels， The verification has indicated that the generalized synthesis load model proposed has good description ability, generalization ability and parametric stability.

Abstract:A new topology of on-line UPS based on Z-source inverter was proposed. The new topology could not only output a perfect sine wave under no industrial transformer, which decreased the volumetric size and cost of the UPS system, but could act on inductive loads besides capacitive ones. And a charging and discharging circuit based on Buck/Boost topology was added, where the battery's rated voltage could be smaller, which could reduce the power supply's volume and lessen the voltage stress of switch components. Moreover, an active power factor correction circuit based boost topology was provided in the topology' input, which could improve input power factor and reduce harmonic pollution. Simulation and experiment results were provided to verify the correctness and effectiveness of the new UPS.

Abstract:The inhibitory activities on α-glucosidase of .Camellia. cake polysaccharides (CCP) isolated and purified from .Camellia. cake were investigated in vitro assay systems. The results showed that CCP contained arabinose, galactose, rhamnose, galacturonic acid, glucose and mannose, with a relative molecular mass of 3 000～12 000. It has been demonstrated that CCP has appreciable α-glucosidase inhibitory effect in a concentration-dependent manner. The IC50 of CCP was 0.053 mg/mL, and CCP can be considered as a potential candidate for α-glucosidase inhibitors.

Abstract:SiO2/AC composites were prepared in sol-gel method with tetraethoxysilane (TEOS) as the precursor and active carbon (AC) as the carbon resource. XRD, SEM, BET and electromagnetism parameter analyses showed that the structures, electrical conductivity and electromagnetism parameter varied with the content of SiO2 in SiO2/AC composites, and the microwave absorption could be improved with SiO2 content. It has been found that the active carbon and TEOS will form a homogeneous mixture formation through sol-gel method, the reaction velocity is slower and the generated SiO2 particles are smaller when the temperature is low. The electromagnetic parameters and electromagnetic wave absorption properties of SiO2/AC composites will change if the content of SiO2 is changed. When the content of SiO2 is 12%, the absorption property is the best.

Abstract:In order to examine the male toxicity of nonylphenol after it enters the body, the estrogencity and potential mechanisms of mixture of nonylphenol and 17-Estradiol (E2), a typical natural estrin on rat sertoli cells, was studied. The results indicated that nonylphenol and E2 could promote the growth of sertoli cells, showing certain male toxicity, and their mixture showed significant enhancement effect. Furthermore, E2 did not impact the expression of vimentin protein, a key protein in sertoli cells. Nonylphenol increased its expression, and the mixture significantly increased its expression. Mechanism study showed that, among the three pathways of MAPK channel, ERK protein was the key for E2 enhancing nonylphenol male toxicity. Both nonylphenol and E2 decreased the expression of ERK protein, but the mixture increased its expression. Nonylphenol noticeably promoted the expression of p-JNK protein and p38 protein, which was weakened when mixed with E2. Consequently, as the result of ERK channel activation, the mixture of nonylphenol and E2 significantly increased the expression of transcription factors, c-Myc proteins and cyclinD1 proteins.

Abstract:Through an analysis of the current pollution of Qingshuitang District of Zhuzhou City and the causes, it is pointed out that the pollution resulted from the unreasonable industrial structure. According to the geographical conditions and actual situation of Qingshuitang Industrial District, lessons from domestic and international management of industrial district pollution, this paper compared the advantages and disadvantages of relocation, remodification and the building of a circular economy park, and put forward a management mode in which some companies be moved to other places, some be remodified in situ, and some coarse processing be extended and established into circular economy parks. It also pointed out the advantages of the mode of comprehensive management and the problems that should be paid attention to.

Abstract:In order to improve the cooperative communication quality, this paper proposes an opportunistic cooperation scheme with adaptive Decoding-forward (DF) relaying, and analyzed the system performance of this scheme by establishing a general mathematic probability model. Based on the derivation of the system probability density function in Rayleigh fading channels, the closed-form expressions of the average spectral efficiency, outage probability and average bit error rate were obtained with the system in link adaptation. Monte Carlo simulations have shown that this adaptive decode-and-forward opportunistic cooperation outperforms previous systems and has about 30% higher average spectral efficiency than the Amply-and-forward (AF) cooperative system.

Abstract:This paper focused on a multi-channel cooperative-based channel VANET (Vehicular Ad-hoc Networks) routing. We proposed a contention number and the delay of a link as the main parameters of the routing,and designed a new routing metric MCCM (Multi-Channel Contention-aware Cooperative Metirc). The routing metric captured location-dependant contention between both intra-flow links and inter-flow links, and the multi-channel and the MCCM were applied to the routing selection, on the basis of which this routing algorithm had better performance on adapting the VANET virtual nodes and the virtual links. We further put forward a new distributed routing protocol MCCR (Multi-Channel Contention-aware Cooperative Routing). Simulation results have shown that MCCR routing algorithm can effectively improve the network performance such as total throughput when the node density and the communication traffic increase.

Abstract:This paper used multi-variant regression method to study the effect of CEO overconfidence and CEO power on corporate investment behavior. Empirical results show that CEO overconfidence plays a significant role in promoting corporate investment spending, while the effect of CEO power on the corporate investment spending is not significant, but strengthens the influence of CEO overconfidence on corporate investment behavior. This study also reveals that the influence on enterprise investment spending from CEO overconfidence differs as the result of various power intensities from different CEO. So, the effect of CEO power on enterprise investment spending differs with the overconfidence of CEO.

Abstract:By comparing four different stochastic volatility models, this paper attempted to find out whether the extreme realizations out of a stock market return time series can be interpreted as a tail behavior of a non-Gaussian distribution, or as the superimposition of a jump component on a Gaussian diffusion, or as a phenomenon in which both forces are at work within the same data generating process. An empirical study of Shanghai stock composition index daily returns data shows that China's Shanghai stock market volatility is characterized by obvious leptokurtic (fat-tail) and lower persistence. In addition, the jump parameters can be estimated precisely due to enough excess returns, which means the stock market is heavily affected by various related government policies. And model comparisons between the two return series show that SV models with a jump component can sufficiently describe a return time series with dramatic moves, not one with mild volatility.