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The calculation of the fundamental frequency for the beam system structures is the important content in the dynamic design of the structure. This paper takes the basic unknown numbers of the displacement method to express the deformation of each member in the beam system structure. The calculation method of the fundamental frequency for beam system structures is got by the energy variational method. The method is very simply and could provide reference for the design of beam system structures.

Recent advances in secure information and Bayesian methodologies have paved the way for randomized algorithms. Here, we verify the evaluation of multi-processors. This is an important point to understand. In order to fix this issue, we concentrate our efforts on arguing that courseware and consistent hashing can collaborate to overcome this riddle.

Precision steel ball is one of the most critical components for rolling transmission. As precision ball affects the performance of precision transmission system, fully inspection of these balls is an urgent need for the industry. This paper is to develop a real-time inspection system for surface defects of precision steel ball with fast and robust method and mechanism. The developed system consists of an optical measurement module as well as a mechanism module for full surface inspecting of the steel ball. The minimum defect and area can be detected by the developed system are 0.1mm and 0.01 mm2 respectively. The developed system has been testified against the designed specifications at speed higher than 3pc/sec and less than 0.5% missing rate. It verified the resolution, accuracy and robustness of the developed system which is capable for final defect inspection of steel balls for grade 100 bearing.

The curved surface of friction forging mould parts is a smooth surface which consist of circular arc camber and slope surface. Using UG as a platform, we can Carry on the processing programming and tool path simulation for the friction forging mould parts. According to the same parts we can use different cutting ways and methods to processing programming. By comparing the different cutting ways,we can obtained the optimal tool path and the ways to solve round knife phenomenon. In this way, we can Complete the programming of the forging mould parts and improve the correctness of the programming efficiency. The program's establishment method and thought Can act as a reference for the parts which has the same characteristics.

The calculating algorithm for Cutter Contacting (CC) paths is proposed in this article to enhance machining precision of complex surfaces with a flat-end cutter. With the style of coordinate transformation, effective cutting shape and equavellent machining radius of a flat-end cutter had been calculated and deduced, and the step-over distance formed by two adjacent CC paths were also obtained. The corresponding NURBS path of tool center points including knot vector and controlling points was obtained from the cutter contacting points.The parameter increment along the CC path interval direction was calculated by using geometric analysis of the local area of CC point.

In this article, a new method with Non-Uniform Rational B-Spline (NURBS) technology is presented and realized in a location and federate controlling system. In the method, the tool paths and the cutter locations (CL) were represented into NURBS curves based on the same knot vector. The above CL data was firstly calculated and then transformed to five motion commands of five axes of machine through the real-time post-procession algorithm. The acceleration/deceleration controlling method is also presented to avoid the impact of machine. The proposed 5-axis spline interpolation method is realized and the experimental result of machining shows that the method is valid.

In this paper,we have studied the overtaking process on the two-way four-lane highway in China by using the theory of multi-objective programming, establish a traffic volume model and evaluate the safety of overtaking. In order to working out the optimal offset angle, we also establish the function equation between safety coefficient, traffic flow and the offset angle during overtaking or lane-changes. Finally some safer and smarter overtaking rules are put forward by combining the offset angle and the security constraints, thus improving the safety, intelligence and traffic flow.

In order to enhance machining precision of complex surfaces with a flat-end cutter, the generating method of cutter contacting (CC) paths is presented in this article. With the method of coordinate transformation, effective machining radius of a flat-end cutter had been deduced and the step-over formed by two adjacent CC paths were implemented. The parameter increment along the CC path interval direction was calculated by using geometric analysis of the local area of CC point. The corresponding NURBS path of tool center points including knot vector and controlling points was obtained from the cutter contacting points.

Urban water is an important part of urban water systems, Predicting urban residents water is the important work to ensure urban people's lives and to achieve urban water resources supply and demand balance. For BP algorithm existing problems in the training process, this paper uses resilient BP algorithm to improve it. Firstly, analysis of the impact factors of urban residents water for adjusting the prediction model; Then, the study on resilient Back Propagation algorithm, to overcome the adverse effects of gradient amplitude; Finally, the study identifies number of hidden nodes, dynamically adjust related parameters, data normalization and so on predict key steps. The results show that the convergence rate of resilient BP algorithm is faster than increased the momentum item of BP learning algorithm and variable learning rate of BP algorithm , it is simple to achieve and does not consume too much memory.

In order to reasonably organize production and to provide services, the use of computer simulation technology to research and analysis for a variety of discrete event system, the system can understand the dynamic operation rules to help people make decisions. This paper studies service completion event processing. First, research the queuing system based, according to the input process, queuing rules and service organizations, the establishment of a variety of models queuing system; then, research customer service time distribution, the mathematical model of exponential distribution and the use of a graphical representation of function curves; finally, research services completion event processing procedure through a flow chart describing the detailed design process, and the three main steps to achieve doing instructions. The research contents of this paper, to promote the application and development of computer simulation discipline is of great significance.

BP learning algorithm has advantage of simple structure, easy to implement and so on, it has gained wide application in the malfunction diagnosis and pattern recognition etc.. For BP algorithm is easy to fall into local minima shortcoming cites simulated annealing algorithm. Firstly, study the basic idea of BP learning algorithm and its simple mathematical representation; Then, research simulated annealing algorithm theory and annealing processes; Finally, the study makes BP algorithm combine with simulated annealing algorithm to form a hybrid optimization algorithm of simulated annealing algorithm based on genetic and improved BP algorithm, and gives specific calculation steps. The results show that the content of this study give full play to their respective advantages of two algorithms, make best use of the advantages and bypass the disadvantages, whether in academic or in the application it has a very important significance.

The article established the mathematical model of ultrasonic flaw echo signals. First, the basic theory of wavelet transform is introduced, the principle of the wavelet threshold de-noising method is analyzed; Then on the basis of soft and hard threshold function, the paper proposes a method based on lifting wavelet de-noising. And from two aspects of signal-to-noise ratio (SNR) and mean square error (MSE) the de-noising performance is analysed. The results show that the method improved the shortcomings of soft and hard threshold de-noising method, and got a better de-noising performance and higher signal-to-noise ratio. So in real-time signal de-noising aspect the lifting wavelet has a very good application prospect.

Discrete event systems are widely used in the production and life, it is difficult to use conventional differential equations, differential equations, and other models to describe, the theoretical analysis method is difficult to obtain analytical solutions, computer simulation techniques to solve these problems provides an effective means. Arrival event is a typical discrete system event; on arrival event handling is always one of the difficulties of computer simulation, in this paper, banking customer arrival system as an example to study. For banks queuing system, customers arrive to obey the parameter of Poisson distribution is, the probability mass function through the distribution curves and cumulative distribution function curves to study the distribution of customer arrival; construction of single-queue multi-server system of customer arrival event subroutine flow chart, and processing steps will be described. Content of this study, it is suitable for the developed area bank to adopt "number ticket machine" approach to service.

BP neural network in character recognition, pattern classification, text and voice conversion, image compression, decision support and so on aspects has the widespread application, in view of the problems existing in the actual application, this paper researches learning algorithm and software implementation. Learning algorithm studies include three aspects, illustrates the basic thoughts of the BP algorithm, designed the three layers BP network structure, the mathematical model for the accurate description of algorithm. Software implementation studies include two aspects, the network model of all neurons become linked list structure and storage structure is designed, the design of the software process and will implement the process into four steps. BP algorithm of the software implementation is a basic work for the application of BP neural network, using the research results of this paper, the user can easily neural network design and simulation.

With the development of information technology, computer simulation technology has become a necessary mean for many complex systems analysis, design, testing, evaluation and other work. Time step method to carry on the research is applied in this paper according to the situation of simulation on time process control complex for computer. First, time step method mechanism describes by graphics; Then, we can research on the simulation of process control procedure, including the system's entity scan, all kinds of events scan, entities and events to combine scan; Finally, we can study on the same time step method that usually used on the computer simulation of process control. Content of this study provide technical and methodological support for computer simulation. With the deepening understanding for computer simulation technology, computer simulation of process control based on the time step method is bound to get a wide range of applications.

A multi-level model automotive service performance evaluation model was established based on the servicer-core automotive service network model was proposed. The model was divided into three interrelated levels: the business level, the process level, the learning and development level, respectively used to evaluate business conditions, operating process and development potential of the object. A fuzzy AHP evaluation model for automotive supply chain collaboration performance evaluation was established. A case study was used to show the feasibility of this evaluation model. The results show that, supply chain collaboration performance result of the object was slightly lower than the regional average. Services of the object had unbalanced development and some indicators had great room for improvement.

Based on the size of casting surface parts and the product quality, expendable pattern casting as a new casting method, it greatly improve production efficiency and save the manpower. With the cast process of mixing arm, as the study objective. It can preliminary identify the process plan by analysis of structure of workpiece surface and the casting process. It obtained the registered product under the considering of the main parameters and the rough size. The researched results can supply the reference value for the design and research of the expendable pattern casting.

A meat pigeon production management information system was developed. The system can carry through precision management for meat pigeon, which adopts RFID, computers and other IT technologies. Pigeon production management information system include two parts: breeding information collection handheld terminals and pigeon management information software system. The breeding information collection handheld terminal can collect production information of breeder pigeon. Breeding information collection terminals include electronic tag reader module, database storage module and human-machine interaction module. The pigeon management information software system can storage and statistics the data that collected by information collection terminal and can also generate standard breeder production record report for workers.

Novel reaching law to nonsingular terminal sliding mode control for the control of the second order nonlinear uncertain system is introduced in this paper. The problems of singularity, chattering and slow convergence of the terminal sliding mode control, and verify the stability of the new controller is analyzed. Due to the premise of eliminating the singular value in the nonsingular terminal sliding mode control, the new reaching law based on the power reaching law enables the finite time convergence of the system equilibrium. By applying the new controller to the inverted pendulum system, the sliding surface had been proved fast and the system chattering had been reduced at the same time. Simulation results indict that the system converges to the equilibrium in a short time and the proposed method is feasible and effective.

In order to the integrated design of the geometric parameters and drawing the pulley parts, based on R & D platform of the VBA with the CAD software, hence after analyzing the selection belt type, determine the reference diameter of the belt pulley, choosing length and the amount of the belt, and designing and drawing the pulley parts, in which include the drawing the tooth of v belt pulley, chamfers and grooves, keyway, hatches, and part dimension, etc. Conventional belt drive system is successfully developed. The design results show that the program is running smoothly, the result is correct with the friendly interface, it can provide a convenient tool to rapidly design of project for the belt drive system.

Acoustic source orientation is an important feature in robot audition. This paper applied a spatial cone six-element (SCSE) microphone array and combined with the time difference of arrival (TDOA) between pairs of spatial separated microphones to estimate acoustic source orientation. Simulate three stages of the acoustic orientation process in a real indoor environment, and results show that the algorithm is simple and effective, reducing the amount of calculation, having anti-noise and reverberation ability to meet the requirements of orientation accuracy.

A method for perception and map construction of the unknown environmental information is described in this paper by analyzing and processing the data measured by laser range finder (LRF). The structure of the laser range finder, the structure of its returned measurement data, its working principle, and communication protocol are presented. The physical meaning of the data are studied and illustrated as well as its representation methods. The corresponding algorithm routine and the GUI interface program are introduced. Experiments are conducted to verify the range finding accuracy of the sensor and the data visualization method is also introduced. Results indicate that the proposed method is sufficiently valid and can satisfy the desired requirements.

A greenhouse monitoring and control system based on Zigbee networks was developed. This system consists of greenhouse data acquisition controller and greenhouse remote monitoring and control software. The system could monitor temperature and humidity, soil water content and concentration of carbon dioxide in greenhouse and could save these greenhouse data to database. Greenhouse acquisition controller had two kinds of control modes, including local manual control mode and remote wireless control mode in monitoring center. Greenhouse remote monitoring and control software can collect, display and record the collected data, also can control greenhouse environment. According to the current indoor temperature, the target temperature and the offset temperature, PID control method is used for temperature control in greenhouse. The system is implemented using low power wireless components, and easy to be installed. A good wireless solution is provided by this system for centralized management of the greenhouse group.

The concentration of cadmium ion in textiles was measured with the method mentioned in Oeko-Tex Standard 100 requirements and GB/T 2912.1-1998 standard. The results show that the measured concentration of cadmium ion fits the normal distribution well after resampled by the method of bootstrap. In the paper, the exposure routine through skin is defined as the object of study, and calculating model of cadmium ion exposure in textiles in the condition of exposure simulation is established. Effective concentration is defined as the confidence limit (UCL) when the confidence level reaches to 95%, and the amount of cadmium exposure to human through skin is obtained, which is 3.2510-4μg/(kg·d).

To settle out the problem of detection movie audio event change , this paper proposed a method of movie audio event change detection. In order to escape missing real audio event change points in the two steps method, one sep method is proposed, penalty distance which is gotten by modifying Bayesian information criterion is used to detect audio event change in movies. The experiment result shows that the proposed method can reach above 62% in F1.

In order to reduce excitation system swing and resultant reactive power swing, namely, reduce external electromagnetic interference to stable operation of 600MW generating unit, the paper analyses unit excitation control mode and designs hardware and software of excitation system. First, digital microcomputer control system organization was designed based on nonlinear control theory, which had an increase of control mode such as PID control mode, nonlinear optimum electronic control (NOEC) mode besides original voltage difference and current control mode. Second, full duplex collocation configuration mode of excitation system was designed, namely two controllers were master-slave concurrent, and each controller could meet excitation requirement of various operation condition including constrained excitation. Finally, in electric network disturbance test, measured excitation system parameters recovered stably in 1020 ms such as stator voltage Ut, rotor voltage Uf, comprehensive amplified control voltage Uc, active power P and reactive power Q. It is verified that transient stability and unit operating condition are improved.

There were lot of shallow-buried mined-out area in the western China, which had severely affected the safety in production and the eco-environment. The viable treatment method was analyzed according to the characteristics of mined-out area. By companion, the comprehensive treatment method of excavation- backfill-eco-restoration was put forward. Then the key techniques for this method were analyzed. The strongpoint for this method was that the coal mine resource can be utmost utilize, the eco-environment problem can be thoroughly treated, and at the same time, it can solve the problem of lack of finances, and mobilize the initiative of the enterprises to participate in mined-out area treatment. It is suitable for shallow buried mined-out area with yard to store the excavation material. But the effect of treatment still needs a further monitor over a long period of time.

As one of the most popular materials used in construction, concrete is prone to superficial flaws, such as crack, due to the load-bearing and external environment. This research manually made cracks of 2 mm with 100 mm length and 30 mm depth on concrete vessels as specimens. Subsequently, bacteria, specifically B. pasteurii, was used in crack rehabilitation to enhance the compression strength of the repaired concrete. The mixture of microbes, urea medium, and urea-CaCl2 medium was added to a sludge and fine aggregate with a weight ratio of 0.6:1:1 to be the repairing material for crack rehabilitation. Crack rehabilitation was conducted by injected the mixture into the test samples after 90 days curing in saturated lime solution. In addition to the traditional test – compression test, scanning electron microscope (SEM) was used to examine the structure composition of the microbe-repaired concrete for calcium carbonate crystal formation. Various rectangular and polygonal crystals were observed in the SEM photographs of the microbe-repaired concrete samples with high bacterial concentrations demonstrated that bacteria can induce calcium carbonate precipitation to complete crack rehabilitation. The results prove that high concentration of bacterial broth induced a great amount of calcium carbonate precipitate and improved the concrete strength of the microbe-repaired samples.

Disappearing mould casting is a new accurately processes with nearly free margin and precision forming, in which is no modulus, no parting, no sand core, so the casting without splash, burr and taper angle. It can improve the dimensional accuracy of the core portfolio for complex surface of the key compose of the disappearing mould. It has completed the design and manufacturing of these by the three-dimensional CAD/CAM technology, and obtains a series of effective methods and experience for the development of the products. The researched results have important directive to production practices for the design and machining process for the expendable pattern casting.

A study of buffeting control of the E-dong Bridge Using an indiscrete tuned mass damper (ITMD) system is performed in this paper. Different from the traditional multiple tuned mass damper (MTMD) system which is fixed along the main span of bridge discretely, this indiscrete tuned mass damper is attached to the centre region of the bridge’s main span continuously. A three-dimensional finite element model of E-dong Bridge, is completed by the software of ANSYS. By comparing the vertical and lateral buffeting response of bridge without dampers, the control efficiency of ITMD and MTMD is confirmed.

In recent years, the reservoir sediments have been a disturbance to Taiwan government, and are getting worse due to the climate change. Consequently, it becomes an urgent issue for the authority to dredge and dispose reservoir sludge effectively. Material researchers in civil engineering and environmental engineering, cooperating with microbiologists and geochemists, have recently attempted the solidification of sludge granules into sandstone-like materials employing microorganisms. The aim of this study is to investigate the approach to solidify sludge or soil particle rapidly to attain strength through the growth of bacteria and apply the technique in practical. In this research, we used Bacillus pasteurii in the solidification of reservoir sludge. The sludge used in the experiment has a moisture content of 40%. The change of bacteria broth culture concentration (0%, 25%, 50%, 75%, and 100%) and CaCl2 ratio in the culturing Urea-CaCl2 medium (10%, 30% and 70%) were used as the experimental variables. The culture broth was mixed directly with reservoir sludge to form a cubic specimen (50 mm x 50 mm x 50 mm), which was then used in compressive strength, XRD and SEM test. The test results showed that being cultured in 70%-CaCl2 medium, the specimen blended with 100% bacteria broth had the highest compressive strength. Compared with the blank samples (0% bacteria broth), the compressive strength was enhanced by approximately 13.48%. Also, it was suggested that the solidification by bacteria can indeed enhance the compressive strength of the cube. The sludge solidified with bacteria cultured in 70%-CaCl2 medium has the highest compressive strength. The result also showed that the higher the content of CaCl2 used in the culturing medium is, the more CaCO3 deposit is induced by the bacteria.

This paper takes a Chinese Changjiang River highway bridge as engineering background, and a kind of continuous three-dimensional (vertical, lateral and torsion)controllers which can apply in the large span cable-stayed bridge is presented. The controllers can control vertical, lateral and torsional response of bridge wind-induced vibration at the same time. Through comparative wind tunnel test of the bridge model with and without controllers, some important conclusions are made as follows: when the continuous three-dimensional controllers are installed on the bridge model, its flutter critical wind speed increases significantly (mostly increases 33.36%); Meanwhile, there is a certain degree of reduction in its RMS values of vertical, lateral and torsional angular displacement response.

In order to increase the efficiency and reliability of dynamic and static force analysis for spatial multibody systems containing the coupling of multi-energy domains, a method based on gyrobondgraph is introduced. The procedure of modeling spacial multibody systems by bond graphs and its dynamic principle are described. The unified formulae of driving moment and constraint forces at joints are derived based on gyrobondgraph, they are easily generated on a computer in a complete form. As a result, the very difficult algebraic problem caused by differential causality and nonlinear junction structure can be overcome, and the automatic dynamic analysis of multibody systems on a computer is realized. By a practical example, the validity of this procedure is illustrated.

In order to achieve active health monitoring of seven-wire steel strands, single magnetostrictive transducer with two-layer coil is developed and applied for the excitation and reception of ultrasonic longitudinal guided waves simultaneously. The transducer can be conveniently fixed at any single one position on the helical surface of these structures. The inner and outer layers of its coil are used for excitation and reception respectively with the help of same axisymmetric permanent magnets. Experimental results show that chosen ultrasonic longitudinal guided wave mode, L(0,1) at 140kHz, can be excited and received with high signal-to-noise ratio in steel strands by using the developed magnetostrictive transducer. Furthermore, to identify the performance of the transducer, the detection of an artificial defect is also conducted.

In order to study the buckling mechanics behaviour of the out-of-plane stability of arches with the double symmetry axis section, by mean of potential variational theories, considering the out-of-plane deformation of arches, the out-of-plane stability governing equation of arches was obtained. The problem was solved by the spline function allocating point method. An example was calculated with this paper method. It is shown by comparing the result of this paper with the others that the paper method is reliable and accurate.