Papers by Keyword: Modeling

Abstract: Multi stages such as side span closure, middle span closure, ten years after construction and so on are simulated with the finite element method in the main channel bridge on the left branch of Beijiang River. Many issues such as unreasonable incremental launching force in construction are found. The optimization made the vertical displacement of the main beam controlled, the secondary moment value on the top of the pier by the side bending of the anchorage and the secondary effect of pre-stressed tendons significantly reduced, and the force of anchorage more balanced. Construction sequence optimization can make the construction process more reasonable and provide a reference for the closing segment construction of the bridge.

Abstract: In order to evaluate the feasibility of the hybrid physical– biologically filtration equation of Biological Aerated Filter (BAF) developed previously, the parameters of the filtration equations were determined through the numerical simulation and experimental fitting, and the empirical formula was carried out finally. The results showed that experimental data were in agreement with the simulated data very well, illustrated that the determined parameter was reasonable and the equation can be used to forecast the headloss development of the tested filter.

Abstract: Biological Aerated Filter (BAF) has been global applied in secondary and tertiary wastewater treatment process in the past decades. As the increasing application of BAF, it was required to get deeper understanding of the operational discipline, parameter optimization and structural characteristics of BAF to improve the treatment efficiency and to operate stability constantly. In this paper, a physical filtration equation of clean filter bed was established firstly based on an average porosity ratio equation and Kozeny-Carman filtration equation. And then the influence of biological oxidation and biofilm development were introduced, of which the Eckenfelder mode and oxygen transfer were considered, to induce a hybrid physical- biologically equation to describe the headloss development in the BAF.

Abstract: A new model concept for predicting mechanical oxide scale failure is applied to Al₂O₃, Cr₂O₃, Fe₃O₄ and NiO. The calculated critical strain values are plotted versus the physical defect size using a simplified version of the original h-w-concept. A limited number of experimental data existing in the literature were entered into the plots and yield satisfactory agreement with the model data. Future efforts should focus on extending the experimental data basis and converting these data into h-values for the model.

Abstract: Abstract. Based on the redefined flow rate and flow pressure, the forward and backward state equations of long-stroke valve-controlled asymmetrical cylinder system are set up, in which the general mistakes in building up the flow rate equation are avoided. Then the simulation model in MATLAB/Simulink is established. Adopting the conditional-executive subsystem blocks, joint simulation with different models at two directions is realized by taking into account the continuity problems in positioning reversal. The subsystem of introduced equivalent volume function helps to show the effects of piston working position to valve-controlled cylinder system. Furthermore, with this simulation model, dynamic performance analysis of long-stroke valve-controlled asymmetrical cylinder system including some nonlinear factors becomes convenient.

Abstract: A novel photosensitizer, pentalysine β-carbonyl-phthalocyanine zinc [ZnPc-(Lys)₅] has tendency to form aggregate in aqueous solution. The observed in vivo Photodynamic therapy (PDT) effect of ZnPc-(Lys)₅ suggests a disaggregation mechanism. In this study, the equilibrium binding constant K_a, the numbers of binding sites n and the distance of Forster radii r between ZnPc-(Lys)₅ and human serum albumin (HSA) are measured by Spectroscopy. A molecular model of HSA-ZnPc-(Lys)₅ complex was generated according to these datum. This molecular model provides rationale that the molecular interaction between HSA and ZnPc-(Lys)₅ facilitates the dissociation of ZnPc aggregates.

Abstract: Bionic modeling is a kind of design method which used widely in modern design. And high fashion is the highest interpretation and artistic expression of fashion designers to garments. With flexible application, sophisticated skills and exquisite workmanship among high fashion, bionic modeling is an artistic modeling form that has high research value. Mainly, its artistry reflects on garments’ modeling, color, fabric, texture, etc. Bionic design method broadens high fashion design plan, which expresses an extraordinary creative ability of fashion design.

Abstract: In practice a MOSFET is anti-parallel with a diode. In the paper there is a method how to build its model. The model applies for the MOSFET works as a power switch. The model consists of two capacitors, a voltage-controlled switch and a diode. There is an example for the model building. The circuits including the model are simulated. The results prove that the electrical data of model equals basically its actual data. The model can help electrical engineers design circuits which uses MOSFET as a power switch. The model built only need the data of its manual. The merit is very suitable for electrical engineers.

Abstract: In this paper, a modeling method is presented for networked control systems (NCSs) of electric multiple units (EMUs) with packet dropout and network-induced delay. It is assumed that the induced delay is less than the sampling period T, and the event rates (scilicet, the data packets transfer successfully rates) are fixed. The NCSs in EMUs can be described as an asynchronous dynamical systems which are driven by "events" that occur asynchronously. Using the dynamic output feedback control method, the systems exponential stability is discussed when the system state is not acquirable.

Abstract: Based on the working principle of the TC2400 Tower-belt, the power bond graph of the hoisting mechanism hydraulic system was established under the listing loads condition. The dynamic equations of the system were deduced according to the logical relations amongst the established power bond graph variables. Based on the dynamic equations of the system, the system’s simulation model was established using the block diagram of SIMULINK. By setting the simulation parameters of the hydraulic system, this simulation was carried out, and the performance curve of the hydraulic system was obtained. The simulation results checked the validity of the simulation method, proved the feasibility to build model and simulate the hydraulic system of the large construction machinery by combining power bond graph with SIMULINK, and provided a theoretical direction for improving and optimizing the system.