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Based on the dynamic model of 1/4 vehicle suspension, an active control system is designed using the fractional order exponential reaching law of model following variable structure control strategy. An active suspension with linear quadratic optimal control is used as the reference model. The sliding mode switching surface parameters is designed by pole placement method to ensure the stability of the system. At the same time, combined with the index reaching law proposed by Professor Gao Wei Bing and the definition and properties of fractional index, constructs a similar fractional order exponent reaching law to improve the dynamic quality of sliding mode motion. And in MATLAB, system modeling and controller design are implemented. By setting up experiments, the different suspensions are compared. The results show that compared with the passive suspension, the performance of the vehicle can be improved better, and the performance of the tracking reference model has good tracking performance. Moreover, compared with the integral exponential reaching law, the chattering can be more effectively weakened. Finally, before and after the change of vehicle parameters in the simulation, the results show that the system has good robustness.

Hexagonal (β)-phase NaYF4:Yb3+, Er3+ upconversion nanoparticles (UCNPs) with and without an inert (undoped NaYF4) shell have been successfully synthesized and the effects of shell thickness on the upconversion luminescence (UCL) and temperature sensing properties were systematically investigated. It was found that the NaYF4 shell and its thickness do not affect the RHS values and thermal sensitivity, but can obviously improve the UCL intensity of NaYF4:Yb3+, Er3+ UCNPs. It implies that the core-shell structured NaYF4:Yb3+, Er3+@NaYF4 UCNPs with excellent UCL properties have great potential to be used as temperature sensing probes in biomedical fields, without considering the influences of the shell thickness on their temperature sensing properties.

It has been proved that the mold filling under low pressure casting can be described by the second order nonlinear differential equations characterized by damping oscillations. To obtain higher accuracy of the velocity field, the mold filling process with damping oscillations should be considered. A computational model taking the liquid level droping in the crucible into account based on two phase flow for filling process of damping oscillations is presented in this paper. Hydraulic simulation with the particle image velocimetry was adopted to verify the numerical simulation result. It is proved that the nemuerical simulation results used the presented model perfecly match with the particle image velocimetry results. Liquid level droping in crucible is the main reason for damping oscillations in mold filling. Velocity oscilations can be eliminated when the melt flow across a sudden expansion section. The detailed flow field based on the presented model can provide guidance to optimize the process parameters.

At present, digital printing technology develops rapidly, but in terms of color reproduction, digital proofing and the traditional mechanical proofing are different, it’s difficult to determine the color reduction according to the dot size, mainly manifested in the difference between the display color and the actual digital output color. In this paper, through analyzing the differences with color management technology, to keep consistency between the original display color and digital proof color as the goal. Through the study, mainly provides solutions for color consistency of digital proofing for paper packing.

Cognitive radio can improve the spectrum utilization efficiency of spectrum band. So spectrum sensing is the key technology in cognitive radio network. Our main task is to design a cyclic detector with better detection performance than energy detector. This paper studies single-user spectrum detector in cognitive radio networks, including cyclic spectrum detector and energy detector. We firstly analyzed the energy spectrum sensing mathematic model for comparison, then we proposed the new simulation model and detailed simulation steps of this cyclic spectrum sensing detector. Simulation results demonstrate that the cyclic spectrum detector has better performance than energy detector while the SNR of channel condition is low.

The dq-axis inductances are important for the voltage decoupling control, torque estimation and steady-state performance analysis of a PMSM machine. In this paper, a measurement method is proposed based on the dq-axis instantaneous flux linkages calculation. The rotor is locked by a positive d-axis current, and then a proper AC current is assigned respectively to the d and q-axis reference current in order to cover the various current ranges. The instantaneous flux linkages are calculated by the integration of dq-axis current and voltage offline. Finally, dq-axis inductances are computed by the integrated flux linkages divided by the dq-axis current.

Numerical investigations of the abrasive influence on material removal efficiency of the micro-hole for AFM process is conducted in this paper. A three-dimensional model is constructed for this process. The abrasive with various particles volume fraction and different micro-holes with various diameters are selected in this study. The simulation results show that the lower particle volume fraction may be in favour of the metal removal uniformity, but the processing time will be too long if too low fraction is selected.

This paper, based on the EDA software platform and VHDL description method, introduces how to use the FPGA chip to control the multiphase stepper motor. This design, through automatic logic compilation optimization and simulation test and compile, finally completed the function of the stepping motor subdivision drive controller. By testing, it can achieve controlling positive &negative and subdivision for stepper angle.

3G standards such as TD-SCDMA use multi-user detection (MUD) at the base station to combat multi address interference (MAI) and inter-symbol interference (ISI). We review Cholesky factorization and Schur algorithm for Zero Forcing Block Linear Equalization. We compare the solutions of different algorithm for ZF-BLE by computation, and analyze the complexity of those methods.

Based on 33-year typhoon information of South China Sea (SCS) in 1980-2012 and NCEP/NCAR reanalysis data, taking Climatology and Persistence (CLIPER) and earlier physical quantities predictors selected by Stepwise Regression (SWR) and Multidimensional Scaling (MDS) methods as model inputs, the Genetic Algorithm-Artificial Neural Network (GA-ANN) forecast model was built for typhoon gale. The forecast verification results for independent samples in MDS-GA-ANN model show that mean absolute error of 24h forecast for wind velocities at 36 grid points around typhoon centers from July to September is 1.6m/s. Using the same samples, the prediction results of MDS-GA-ANN models for independent samples were compared with that of traditional SWR models. Taking July as example, prediction abilities for 29 MDS-GA-ANN models (81%) among 36 grid points around typhoon centers are superior to that of SWR models; only 2 grid points of MDS-GA-ANN models are worse than that of SWR models (6%). Therefore, prediction ability for most of 36 grid points using MDS-GA-ANN models is superior to that of SWR models and can meet business requirements of meteorological stations at present.

This study investigated the wind turbine blade root bolt static strength using the full scale static test, selected the root bolts of 1/4 bridge strain gauge using the finite element analysis method and the dynamic and static strain instrument. The data of the stress loading combined tension and bending bolt were obtained.

Magnesium alloys are very biocompatible and show promise for use in implant device. The focus of this article lies in the evaluation of the degradation performance and biological response of a paclitaxel-eluting biodegradable stent based on WE43 magnesium alloy by in vivo and in vitro studies. The corrosion characteristics analyzed by immersion testing in phosphate buffered solution (PBS) for 24h. Severe corrosion took place reveal fast degradation, lead to the stent strut easily fracture during expanding. The chemical nature of this conversion in vivo was investigated by scanning electron microscope (SEM) equipped with energy dispersive spectrum (EDS). For the endothelial surface coverage and the microstructure of the stent were also investigated by SEM. The results show that the deployment of the stent in arteries was safe, endothelial coverage occurred above stent struts and between struts after implanted 6 weeks, and more slowly than stainless steel stent and paclitaxel-eluting stainless steel stent. The grains boundaries of the stents are easily corroded in vivo environment, which should strongly affect the radial strength and mechanical integrity of the stent, leading early recoil contribute to restenosis.

In this work, a general expression of the thermo-acoustic (TA) emission from nanocrystalline porous silicon (nc-PS) is derived by using a fully thermally-mechanically coupled multilayer TA model. This expression takes thermal, mechanical, and geometry properties of every layer in a multilayer structure, as well as the thermal contact resistances between layers into consideration and hence agrees well with the experimental results. Therefore, many fundamental problems in thermally induced ultrasonic emission from nanoporous silicon can be studied.

Aim at the characteristics of components made up the machine is able to maintain the assembly relationship, this paper put forward the concept of the component structure, discuss the condition of being a component structure. According to the phenomenon that the component structure can contain more fundamental component structure, Component structure was proposed by one or several structural units with three fundamental principles: Join the components structures into the assembly structure, join the level I components structural units to the assembly structure as the assembly structure, join the level II and above structural units providing independent component structure as the assembly structure. Discuss the component definition and classification of structural Unit, division rules and procedures of the component decomposition.

In the same conditions, the accidents of pressure vessel are much higher than other mechanical equipment. Therefore, the study on the pressure vessels in anomaly conditions and the dynamic response and tolerance capabilities of the structure not only helps to the research and development of warning surveillance and prevention technology about pressure vessels in anomaly conditions, but also contribute to the correct evaluation of the feasibility and reliability on the device of early warning monitoring system and the prevent technology. As pressure vessel is widely used and efficiency is enhanced, traditional failure analysis is restricted to test, analyze accidents, find out failure reasons and table proposals. It is realistic to make a modern design system for pressure vessels, judge failure reasons rapidly and table proposals. Keywords: pressure vessel; modern design; working characteristics

The superstructure and foundation of highrise are in a complete system of interaction. Taking the case of project, by comparatively analyzing the computed value which is calculated by applying the theory of interaction between superstructure and foundation and the measured value ,we find that the computed value neatly dovetails with the measured value.

Using the full-band CCD (PL4240 UV, FLI) and Yunnan Zhihai ultraviolet observation camera system (UVYNZH-II) shoot sweat fingerprints on A4 wrapper and A4 printing paper, to comparatively analyze the effects these two camera systems. The clarity and contrast of ultraviolet image captured from Full-band CCD is better than from UV observation camera system, but both devices are able to reflect the fingerprint ridge characteristics. For sweat fingerprints, it is better for the full-band CCD, but under good conditions for sweat fingerprints bridges, UV observation camera system can basically meet the requirements of sweat fingerprint UV shooting.

Based on the actual project example of high pressure gas pipeline crossing earthquake rupture area, the paper shows and explains the way to make stress analysis and strength checking calculation for the high pressure gas pipeline in the earthquake rupture area by the method of finite element.

The three-screw compressor is a special type of positive displacement compressors that has two or more intermeshing screws rotating axially to deliver fluids. Three-screw compressor depend mainly on master-slave screw meshing with each other forming seal cavity so as to delivery liquid from the suction to the outlet. So it is important to design the screw profile accurately to obtain a high volumetric efficiency of the screw compressor. Through the central rotor and idler rotors three-dimensional model, we can directly obtain the central rotor and idler rotors law Section Surface contour and longitudinal section Surface contour. At the same time, this method can also provide a reference model for access complex surfaces checking template.

Tractor electro-hydraulic hitch system is designed with force-position adjustment function. The method of force-position adjustment is proposed. Under the CCS development environment in DSP, system modules are designed according to the characteristics of TMS320F2812, including raise and drop modules, force-position adjustment module. The feasibility of the design is verified by system simulation.

Equipments for distribution automation terminal and the corresponding back-up power that can be cold started directly without heating equipments in natural environment at -40°C are developed to suit the extremely cold weather in Northeast China. The ultimate goal is to realize normal operation at a temperature ranging from -50°C to +70°C.

socarbostyril alkaloids is a kind of alkaloid does not contain basic nitrogen atoms and is represented by hydroxylated benzophenanthridone or isoquinolinone types of structure. The most widely known compounds of this group are narciclasine, lycoricidine , and pancratistatin. They have demonstrated to inhibite the proliferation of many human cancer cells, and at the same time have no affect on normal human cells under a certain dose, they have a high efficiency and low toxicity in antitumor area. Now this kind of compound has been a hot spot research to antitumor workers. The present paper reviews the origin and the antitumor function of the Isocarbostyril alkaloids.

Laval nozzle is the commonly used device in rocket engine and aero engine. this paper, the numerical model is derived. The convergent section subsonic flow and divergent section hypersonic flow are simulated in dimensionless method. Reverting the dimension, the result can be seen that the analytical solution, the CFX simulation solution and the numerical are in uniform.

The purpose of this study is to investigate the extraction and separation of alkaloids from H.littoralis. Chopped bulbs of H.littoralis was soaked in a mixture of dichloromethane and methanol (1:1) for 24 h, ultrasonic extraction six times, then extracted with N-butanol to yield crude extracts. Three components were isolated from N-butanol extract of H.littoralis by Sephadex LH-20 and TLC. The compounds were identified by LC-MS, they are 5,6-dihydrobicolorine, Lycorine and 7-deoxy-trans-dihydronarciclasine.

The rational database including the distribution, changes and testing facilities status of temperature & humidity in tea garden is created using the MapInfo 9.5. A set of the tea garden wireless utilities is established using the ZigBee module. The temperature & humidity real-time monitoring system and early warning system for Frost Prevention is established using Mapbasic. This system can get real-time information of temperature & humidity of nodes in different locations and give frost warning early. The frost prevention fans can be timely started, once temperature inversion happens. At the same time, the manager of tea garden can realize real-time monitor of the work status and quick location of facilities with the help of GPS.

This paper reviews the structure-activity relationship of two typical Amaryllidaceae isocarbostyril alkaloids, narciclasine, pancratistatin and their derivatives. Varieties structures have important impacts on biological activity of Amaryllidaceae isocarbostyril alkaloids, for example, the nuclear structure of isocarbostyril, the stereochemistry of the B/C ring junction, the C7-hydroxy of ring A, hydroxies of ring C and so on. This study is conducive to find other active groups, conduct structural modifications and provide the rational basis for designing drugs molecular.

Recently, various papers investigated the topology identification and parameter identification of uncertain general complex dynamical networks. However, in many real complex dynamical network systems, there exists community or hierarchical structure and node delay. Based on LaSalle’s invariance principle, in this letter, an adaptive controlling method is proposed to identify unknown topological structure for general weighted complex dynamical network with community and node delay. Illustrative simulations are provided to verify the correctness and effectiveness of the proposed scheme.

This study has established a 1/184 model of blade root by using finite element software (ANSYS), and analyzed the stress pipeline and errors of this blade root model. By transforming the loads in blade root and imposing axial step load, especially by analyzing models boundary conditions and the structure of contact surface, the axial stress, bending stress and the other parameters have been acquired.

Narciclasine (NCS) is a plant growth inhibitor isolated from the secreted mucilage of Narcissus tazetta bulbs, which is commonly used anticancer agent in human systems. Refer to the literatures in recent years, this article reviewed the anti-cancer effects of potential anticancer drugsNarciclasine, which induces apoptosis by activation of the death receptor and/or mitochondrial pathways in cancer cells. Narciclasine displays antitumor effects in apoptosis-resistant as well as in apoptosis-sensitive cancer cells by impairing the organization of the actin cytoskeleton.

Qinhuangdao coastal wetland is the distribution of China's most representative of the sandy coastal wetlands, and its main wetland types are sandy coast wetland, rocky coast wetland, estuarine wetland, lake wetland, shallow sea wetland and artificial wetland. Under the influence of natural factors and human factors, coastal wetlands degradation constantly. Land reclamation, city and port development, pollution, coastal erosion and excessive use of coastal biologic resource are considered as the main factors to the degradation of the coastal wetlands. Based on the analysis the main factors contributing to the loss and degradation of the coastal wetlands and the characteristics of wetland degradation, sustainable development countermeasures are suggested in this paper.

In order to develop realistic water resources strategy, we initially analyze the situation of water resources in the United States which present a significant regional difference. Then on the basis of previous studies, we propose the cost formulas of water storage, movement and desalinization. By analyzing the practical application, along with pros and cons of the above three solutions accordingly, we consider that a comprehensive utilization of these measures will be the best water strategy for America to solve the water shortage problem. Later we apply the conclusion to a case study of Southern California, we propose an optimization model which aims to minimize the total cost of the water strategy, and then use Lingo to solve the problem. Results show that 5.946 billion cubic meters of water by transferring is the best way to make up for the water use gap in 2025 and the total cost is 2.94 billion dollars. Finally, we summarize the strengths and weaknesses of our paper. What needs to be emphasized is that our model can also be adapted into the analysis of other states, which shows great flexibility.

AOP(Aspect Oriented Programming) is a programming technology that makes the OOP (Object Oriented Programming) technology more complementary and perfect when being applied together with OOP technology. AOP provides ideal modularized structure for programming. At the moment, AOP has been supported and applied in two leading programming platforms: Java and .Net. Java provides perfect support to AOP, but .Net has not clearly provided the technique to support AOP. Meanwhile, Design Pattern has been widely used in programming. This study analyzes the theory of AOP technique and provides an implementation strategy for AOP based techniques on Proxy Pattern in .Net platform.

When measuring the thermal conductivities of poor conductor with steady-state method, some errors should be introduced through the process of the experimental principle derivation to the experimental data measurement. To satisfy the need of measurement, this study aims to improve the structure of the “TC-I1 Type thermal conductivity measuring apparatus” correspondingly: we placed two fans at the side of the cooling plate, thus effectively control the stability of the strong-force convection cooling environment. This study chose digital thermometer of UT325 Type to collect temperature signals, storing the data on computer and putting such data under fitting process with the software Matlab. Compared with the traditional measurement, the post-modification apparatus successfully achieves lower errors in the coefficient of heat conductivity measurement and thus the results are closer to the inherent attribute values of the sample plate. It’s very satisfactory to the requirements of teaching and scientific research oriented measurements.

In order to study the dynamic response of the cylindrical shell structure which is similar to the missile cabin under the combined effects of axial compressive load and radial aerodynamic load, the equilibrium equation of dynamic response of cylindrical shell is derived based on the Hamilton's principle. The displacement response of cylindrical shell is calculated through employing the numerical method. The calculation results show that the axial displacement response and the radial displacement response of cylindrical shell are much greater than the circumferential displacement response; the radial displacement will be maximum when the excitation frequencies are 285Hz, 594Hz, 1039Hz, 1062Hz, 1093Hz, 1962Hz and 1987Hz; the axial displacement will be maximum when the corresponding excitation frequencies are 81Hz and 294Hz; the peak values of displacement response in non-load plane are not all obtained at the resonance frequency and a certain effect is generated due to the modal coupling. (2013) Trans Tech Publications, Switzerland.

In recent years, Chinese highway transportation problem became more and more serious in the overfreight, which has become a danger for the lives and state property security, and affected social economic coordination but also the social healthy development. The development and popularization of load meter is one of the solution of this problem. In addition, the implementation of more reasonable meter weight charge way also need to load instrument as the foundation. In this paper, based on the infrared detection circuit and microcontroller overfreight scale system of the coach was designed. When the coach pass through load meter with a certain speed, it can weigh out the axle loading of the coach, accordingly it can judge that whether the vehicle is overfreight or not.

By optimizing the matching of automatic transmission of car, it could improve the overall performance of electric vehicles. This article analyzes the structure of the electric vehicle drive train, then selects the automatic mechanical transmission combined with the motor-driven features. Then calculate the parameters of motors, batteries, transmission and other parts. The electric vehicle model was created in the Advisor software, then the simulation conditions were selected to test the car, so the vehicle dynamic characteristics and economy were verified by simulation results.

For the formation control problem of multiple nonholonomic mobile robots with actuator and formation dynamics, this paper propsed a new control strategy that integrated kinematic controller with input voltages controller of actuator. This control law was designed by backstepping technique based on formation control structure of leader-follower. The RBFNN was adopted to achieve on-line estimation for the dynamics nonlinear uncertain part for follower and leader robots. The adaptive robust controller was adopted to compensate modeling errors of neural network. This strategy not only solved the problem of parameters and non-parameter uncertainties of mobile robots, but also ensured the desired trajectory tracking of robot formation in the case of maintaining formation. The stability and convergence of the control system were proved by using the Lyapunov theory. The simulation results showed the effectiveness of this proposed method.

Adsorption of metsulfuron-methyl by kaolinite, goethite，amorphous alumina and the effects of urea on the adsorption were examined with equilibrium adsorption method. Results indicated that the adsorption was in accordance with Langmuir equation, with the maximum absorbing capacities ranking as amorphous alumina (2150 g•g-1), goethite (729.4 g•g-1), kaolinite (529.1g•g-1). When urea was used in the adsorption system, the absorbing capacities of goethite and amorphous alumina to metsulfuron-methyl decreased whatever the addition order of urea and metsulfuron-methyl was. However, when urea was added before or simultaneously with metsulfuron-methyl in suspension of kaolinite, the adsorption quantity of metsulfuron-methyl was increased．

Ignoring the deformation effect, the original size principle is normally used to calculate the internal force and deformations of the bars in Mechanics of Materials, the calculation error is not discussed in the textbooks, however. In order to show the adaptability of the original size principle to calculate the internal force of plane statically determinate truss, a case of the two-bar statically determinate truss was also given. The calculation error of the internal force and the angle deformations are quantitatively studied to make a comparison between the actual internal force and that calculated by the original size principle. The research showed that the relative error of angle deformations and the internal forces of the two rods are nonlinear dependent on the external forces (the given force), tensile stiffness and the initial angle of the plane truss. If the strength and tensile stiffness of the bars can meet the requirements of engineering, the original size principle can be used to calculate the internal force of metallic bar truss under the conditions of small deformations.

In order to optimize the space below railway lines of high-speed railway station, a pedestrian traffic simulation was presented. Hefei South Railway Station was taken for example, and the cumulative mean density, space utilisation, evacuation parameters of space below rail lines were analyzed according to the layout of yards and traffic organization schemes. In addition, the passengers’ distribution to different transportation modes, which includes subway, bus, and taxi, was also valuated.

A new algorithm for training radial basis function neural network (RBFNN) is presented in this paper. This algorithm is based on the dynamic fuzzy clustering method (DFCM). The algorithm has a number of advantages compared to the traditional method based on k-means. For example, it does not need to know the number of the hidden nodes and to predicts more accurately. Due to these advantages, this method proves to be suitable for developing models for complex nonlinear systems.

Recently, more and more companies are using wireless location technology to improve advertising effectiveness, such as location-targeted advertising. Location-targeted advertising involves the provision of ad messages to cellular subscribers based on their geographic locations. Location-targeted advertising opens up an innovative conduit to deliver ads and coupons that are customized to an individual’s tastes, geographical location, and time of day. Although location-targeted advertising seemingly offers practitioners tremendous potential given the ubiquitous nature of mobile devices, we know very little about it. This paper summarizes up-to-date research findings of location-targeted advertising, and makes managerial implications of how to use this technology efficiently.

Tidal drainage effect of confined aquifer is important to well tide interesting many relevant researchers. Through tidal analysis of water level monitoring in Chuan06 well, this paper explored the tidal drainage effect of the confined aquifer and its influence on the well tide. It indicated that: the changes in phase shift (η) and amplitude response (A) were attributed to the changes in transmissivity (T) rather than that in storativity (S), and the tidal drainage effect of isotropic aquifer could be effectively described by Hsieh model.

The Risk Based Corrective Action (RBCA) Tool Kit for Chemical Releases was used to develop Soil Screening Levels (SSLs) for contaminated sites assessment in Beijing. A total 88 contaminants, including inorganic compounds, volatile organic compounds, semi-volatile organic compounds, pesticides, polybrominated biphenyls and others, were identified as the priority compounds of concern, and a range of exposure parameters, toxicological data and site factors based on the environmental monitoring data from several contaminated sites in Beijing, were used as model inputs to derive SSLs. The proposed SSLs were evaluated and validated by comparing with corresponding values in some other countries/regions. The present study has an important guiding significance for the development of risk-based SSLs in other provinces/cities of China.

Tailan river basin is a typical drought river basin in northwest China where construction of underground reservoirs is approved as an effective way to solve the problem of water resource shortage in the river basin. In order to ensure water supply efficiency of the underground reservoirs of the basin, it is necessary to research their recharge and supply patterns and to optimally operate them. This paper has, therefore, investigated different recharge locations and recharge ways through numerical simulation of underground flow in an underground reservoir area of the basin to explore a typical scheduling plan for optimal operation of the reservoir. The results show that it is better to recharge the reservoir using the flood season recharge approach at the centre of the reservoir area to ensure its continuous operation. Following from this recharge process, the use of a three-well pumping scheme is regarded as the best choice for optimal water supply from the reservoir. Also, the study indicates that for the same recharge amount, if the recharge time is closer to the pumping peak, then there is the more obvious effect of underground level recovery; the recovery is much better if the recharge time is more concentrated.

In view of the toxicology and hazardous nature of the submicron particles, it is paid more and more attentions of the domestic and foreign research scholars. In this paper, we introduce the research progress on recognition, attributed and formation mechanism of submicron particles in the world. Simultaneously, the controlling technologies of submicron particles are discussed. The application tendency and the existence problems of the controlling technologies are analyzed. At last, the future research directions are put forward for submicron particles control.