平面向量的实数化模型

平面向量的运算变形规律与代数运算变形规律有许多相似之处,但更多有其特殊性.由于代数模型求解容易掌握,具有普遍性.通过恰当变形,将向量中有关问题转化为实数模型去解决,可避免向量运算中作图求解带来的诸多不便,又能体现出方法过程的严谨性.具有一定的实践意义.下面略举几例和转化的方法,供大家参考.

ON OPTIMUM DESIGN OF THE SHEARER DRUM

On the basis of the model experiments, a software for optimum design of the shearer drum has been developed, and the main parameters of a shearer drum also have been optimized. The combination of the techniques of optimization with the mod el experiment makes the designing and theoretical systems of the shearer drum more perfect.

Decision Model of Knowledge Transfer in Big Data Environment

A decision model of knowledge transfer is presented on the basis of the characteristics of knowledge transfer in a big data environment.This model can determine the weight of knowledge transferred from another enterprise or from a big data provider.Numerous simulation experiments are implemented to test the efficiency of the optimization model.Simulation experiment results show that when increasing the weight of knowledge from big data knowledge provider,the total discount expectation of profits will increase,and the transfer cost will be reduced.The calculated results are in accordance with the actual economic situation.The optimization model can provide useful decision support for enterprises in a big data environment.

The Modeling and Simulation of Reactive Distillation for the Esterification Process

In this paper,a generalized model of the reactive distillation processes was developed via rate-based approach. The homotopy-continuation method was employed to solve the complicated nonlinear model equations efficiently. The simulation on the reactive distillation processes was carried out with the profiles of stage temperature,composition and flow rate for both vapor and liquid phases obtained. Based on careful analysis of the simulation results, the pitfalls in experimental design were detected. Finally, a software package for the simulation of reactive distillation processes was developed.

Optical closure of parameterized bio-optical relationships

An optical closure study on bio-optical relationships was carried out using radiative transfer model matrix operator method developed by Freie Universitat Berlin. As a case study, the optical closure of bio-optical relationships empirically parameterized with in situ data for the East China Sea was examined. Remote-sensing reflectance （Rrs） was computed from the inherent optical properties predicted by these biooptical relationships and compared with published in situ data. It was found that the simulated Rrs was overestimated for turbid water. To achieve optical closure, bio-optical relationships for absorption and scattering coefficients for suspended particulate matter were adjusted. Furthermore, the results show that the Fournier and Forand phase functions obtained from the adjusted relationships perform better than the Petzold phase function. Therefore, before bio-optical relationships are used for a local sea area, the optical closure should be examined.

Durability of sea-sand containing concrete:Effects of chloride ion penetration

This paper describes an orthogonal experiment on the effect of water/cement ratio,water consumption per cubic meter,curing time,and type of sand on the response＂resistance to chloride ion penetration＂.A sea-sand containing concrete was used for the trials.An analysis of chloride ion diffusion coefficients at different factor levels was performed.A predictive model of chloride ion diffusion in concrete is developed through regression analysis.The experimental results show that when the water/cement ratio varies from 0.45 to 0.60,and the water consumption per cubic meter varies from 185 to 215 kg,and the curing time varies from 30 to 180 d then the size of the effects fall in the order（most significant first）： curing time,type of sand,water consumption per cubic meter,and water/cement ratio.Chloride ion penetration is reduced,and better durability of the concrete is observed,with longer curing times,less water consumption per cubic meter,and a smaller water/cement ratio.

Kinetic Modeling of the Photocatalytic Degradation of Methyl Orange by Supported TiO2

The photocatalytic degradation of methyl orange （MO） in UV/Supported-TiO2 system was investigated and a kinetic model was presented. The experimental results show that the photocatalytic degradation rate is favored by high concentration of dye in solution and is enhanced by the solution temperature. A simple kinetic model has been proposed which can describe the discoloration process in an adequate way. The calculated results obtained were in good agreement with experimental data. The model predicts the concentration of MO during the photocatalytic degradation process.

GPU Accelerated Marine Data Visualization Method

The study of marine data visualization is of great value. Marine data, due to its large scale, random variation and multiresolution in nature, are hard to be visualized and analyzed. Nowadays, constructing an ocean model and visualizing model results have become some of the most important research topics of ‘Digital Ocean'. In this paper, a spherical ray casting method is developed to improve the traditional ray-casting algorithm and to make efficient use of GPUs. Aiming at the ocean current data, a 3D view-dependent line integral convolution method is used, in which the spatial frequency is adapted according to the distance from a camera. The study is based on a 3D virtual reality and visualization engine, namely the VV-Ocean. Some interactive operations are also provided to highlight the interesting structures and the characteristics of volumetric data. Finally, the marine data gathered in the East China Sea are displayed and analyzed. The results show that the method meets the requirements of real-time and interactive rendering.

Assimilating the LAI Data to the VEGAS Model Using the Local Ensemble Transform Kalman Filter: An Observing System Simulation Experiment

Information on the spatial and temporal patterns of surface carbon flux is crucial to understanding of source/sink mechanisms and projection of future atmospheric CO2 concentrations and climate. This study presents the construction and implementation of a terrestrial carbon cycle data assimilation system based on a dynamic vegetation and terrestrial carbon model Vegetation-Global-Atmosphere-Soil(VEGAS) with an advanced assimilation algorithm, the local ensemble transform Kalman filter(LETKF, hereafter LETKF-VEGAS). An observing system simulation experiment(OSSE) framework was designed to evaluate the reliability of this system, and numerical experiments conducted by the OSSE using leaf area index(LAI) observations suggest that the LETKF-VEGAS can improve the estimations of leaf carbon pool and LAI significantly, with reduced root mean square errors and increased correlation coefficients with true values, as compared to a control run without assimilation. Furthermore, the LETKF-VEGAS has the potential to provide more accurate estimations of the net primary productivity(NPP) and carbon flux to atmosphere(CFta).

Synthesis and optimization of utility system using parameter adaptive differential evolution algorithm

Synthesis and optimization of utility system usually involve grassroots design, retrofitting and operation optimization, which should be considered in modeling process. This paper presents a general method for synthesis and optimization of a utility system. In this method, superstructure based mathematical model is established, in which different modeling methods are chosen based on the application. A binary code based parameter adaptive differential evolution algorithm is used to obtain the optimal con figuration and operation conditions of the system. The evolution algorithm and models are interactively used in the calculation, which ensures the feasibility of con figuration and improves computational ef ficiency. The capability and effectiveness of the proposed approach are demonstrated by three typical case studies.

Using the traditional model to evaluate the active force of the human lateral rectus muscle

The information on the force of extraocular muscles(EOMs)is beneficial for strabismus diagnosis and surgical planning,and a direct and simple method is important for surgeons to obtain these forces.Based on the traditional model,a numerical simulation method was proposed to achieve this aim,and then the active force of the lateral rectus(LR)muscle was successfully simulated when the eye rotated every angle from 0°to 30°in the horizontal plane from the nasal to the temporal side.In order to verify these simulations,the results were compared with the previous experimental data.The comparison shows that the simulation results diverged much more than the experimental data in the range of 0°–10°.The errors were corrected to make the simulation results closer to the experimental data.Finally,a general empirical equation was proposed to evaluate the active force of the LR muscle by fitting these data,which represent the relationship between the simulation forces and the contractive amounts of the LR muscle.