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The variable spraying technology includes two categories: premixed drugs and online mixed drugs. The operators need to be in contact with pesticides in the premixed operation, which is harmful to the operators. Meanwhile it has the disadvantages of large amount of pesticides and environmental pollution. In order to solve this problem, an injection-type online mixed drug spray control system for variable spraying and width control was designed. The required water flow and liquid flow can be set according to user settings or prescription drawings to change the spray concentration in real time. It can mix pesticides as needed and accurately spray pesticides. The injection type online drug mixing control system uses the liquid medicine injection method. This system injects the liquid medicine into the water solvent pipeline for mixing when the water flow rate is stable. a model for the mixing ratio of water solvent and liquid flow was established. Using PID control algorithm to control electric regulating valve to adjust water solvent flow. Real-time detection technology of high-precision drug liquid flow and micro-control method of drug pump are adopted to realize detection and control of drug injection volume. The mixture ratio range measurement showed that the mixing ratio was 10:1-270:1. The spray volume consistency test showed that the spray volume of the four nozzles was generally consistent. The mixed concentration detection is performed under different mixing ratios of the system, and the spatial variation coefficient is less than 5%. It shows that the mixed drug spray control system has better uniformity and stability.

The safety evaluation of construction projects is a very important problem. In the current study, the new smart methods especially for the complexity and variability of construction safety evaluation are absent. Combined with the engineering examples, this paper analyzes the sensitive factors that affect the construction project safety and makes discretizating of influencing factors based on expert and BIM technique. Based on BIM and Bayesian network, this paper established a new construction project safety evaluation model and presented the hybrid methods of strategic learning and knowledge management of technological innovation in construction project safety evaluation. Combined with the example of underground traffic engineering of Zhengzhou city comprehensive transportation hub, the Bayesian network was used to predict its security level. The probability of the safety level of the project in grade 3 is 0.614. Compared to other evaluation methods, presented hybrid method is more intelligent in strategic learning and knowledge management of technological innovation. Through the Bayesian network sensitivity analysis, we can know that the sensitivity factor of the construction project safety in the project is the construction risk, the continuous operation time, the protective measures, the material risk, and the number of maintenance. Presented detailed computational methods and steps in this paper can be used to improve the level of construction project safety effectively and help construction managers to take more effective control measures to prevent or reduce the occurrence of security incidents.

Tornado is one of the most hazardous external natural events which should be taken into account in the siting, design and safety evaluation of nuclear power plants. The tornado hazard has been assessed for a nuclear power plant located in the Southeast China in this paper. Using the original Fujita scale and grading by a number of experts, intensities of the tornado segments have been determined. The design-basis tornado wind speed, parameters and missiles generated have been evaluated following the methodology listed in the hChinese Nuclear Safety Guide HAD101/10. The results show that the overall cumulative frequency and intensity of tornadoes in the site area is not in a logarithm-linear relationship. The expected annual tornado occurrence frequencies of various F scales have been estimated by fitting higher intensity samples. The resulting wind speed corresponding to an exceedance frequency of 10-7 per year seems to be sensitive to the fitting samples. Considering the uncertainties, the intensity and frequency of tornadoes in the survey area, the ultimate design-basis tornado wind speed is taken to be 70.4 m/s, which is the lower limit wind speed of F3 scale. Moreover current problems in tornado hazard assessment in China are discussed.

It is necessary to establish the longitudinal dynamic model of the tractor for the cruise control system to design a fixed speed control algorithm according to the characteristics of the model and the external disturbance characteristics. Aiming at the complexity of the longitudinal power transmission system of the tractor, this paper uses the modular mechanism modeling and the experimental data modeling to establish the longitudinal dynamic model of the tractor. Due to the nonlinearity of the longitudinal dynamics system, the inverse model method is used to linearize the model, which is convenient for the design of control structure and control algorithm of the standard cruise control system. The longitudinal dynamics model is simulated on Simulink, and the model is verified by real vehicle under driving condition. Comparing the simulation data with the experimental data, the results show that the model can accurately reflect the longitudinal dynamics characteristics of tractor, and can meet the requirements for the design of cruise control system.

In order to optimize the recognition accuracy of maize kernels breakage detection and improve the detection efficiency of maize kernels breakage, this paper using computer vision technology and detecting of the maize kernels breakage based on K-means clustering algorithm. First, the collected RGB images are converted into Lab images, then the original images clarity evaluation are evaluated by the energy function of Sobel 8 gradient. Finally, the detection of maize kernels breakage using different pixel acquisition equipments and different shooting angles. In this paper, the broken maize kernels are identified by the color difference between integrity kernels and broken kernels. The original images clarity evaluation and different shooting angles are taken to verify that the clarity and shooting angles of the images have a direct influence on the feature extraction. The results show that K-means clustering algorithm can distinguish the broken maize kernels effectively.

The surge bin is widely used in logistics transportation system. Theoretically it has many virtues, such as reducing the interacting of links ahead and behind bin, buffering different transporting flows, adjusting and processing materials. In practical application, bin capacity size has great influence on reliability and production efficiency of whole logistics transportation system. Studying optimum computing of surge bin capacity to fully realize its beneficial functions are very significance. By utilizing some existing outcomes, this paper presents a new computing mathematical model about surge bin capacity in logistics transportation system. Compared with some existed references, this presented model fully considers different influences of surge bin capacity on reliability and production efficiency of whole logistics transportation system and realizes reliability and production efficiency overall optimization decision. All kind of factors affecting designed surge bin capacity can be easily gotten by the presented model. In addition this paper also presents a set of detailed design computing formulas about surge bin capacity in logistics transportation system, and presents detailed solving algorithm and steps fitted for computer programming. These can offer the reference for capacity decision design computing of surge bin in logistics transportation system.

A new approach based on spectrum analysis of featrue instantaneous power is proposed to detect the rotor bar breaking faults in this paper. Similarly with the difinition of instantaneous power, featrue instantaneous power is still the product of a sampled line voltage and the corresponding line current. The difference is that the currnent used to define the featrue instantaneous power has been filtered out the fundamental component which can produces the constant weight. Compared with the familiar way based on spectrum analysis of the instantaneous power, the proposed approach can get rid of the interference to the fault related characteristic components from the constant weight. The validity of this approach has been verified by theoretical analysis and simulation results.

In computer system, some digital display devices often are adopted. At this time if still select conventional analog interface, digital signal from person computer (PC) need be switched twice by D/A and A/D, lost of video signal will emerge, so a kind of new interface, DVI technology often need be studied. Combining with real project, this paper introduces the detailed developing methods of digital video interface (DVI) transmitter and receiver in computer systems. These include the arranging of the architecture of digital video interface (DVI) transmitter and receiver, the design of over-sampler, elasticity buffer, clock recovery circuit, and data recovery circuits, in addition selecting and designing of phase frequency detector (PFD), charge pump (CP) and loop filter (LF), and voltage controlled oscillator (VCO) in hardware system were discussed in detail. These can offer a kind of reference method for developing of digital video interface (DVI) transmitter and receiver hardware architecture in computer systems.

Universal Serial Bus 2.0 is a kind of new interface technology. It has virtues of high speed, using easily, hot Plug and Play, low-cost, and etc. So it was widely used in all kind of instrumentations and devices, which include personal computers, digital cameras, scanners, joysticks, magnetic tapes, floppy drives, image devises, printers, keyboards, mice, and etc. Universal Serial Bus 2.0 systems consist of USB host control chip and equipment interface control chip, i.e. peripheral device chip. The host control chip was usually integrated in the chip groups of personal computer, its function is single, and some large chip group manufacturers often control its technologies. Therefore the traditional USB developing is only to develop USB peripheral devices, USB peripheral device chips are involved with FIFO and FIFO controller, Direct Memory Access Controller (DMAC), Serial Interface Engine (SIE), USB 2.0 Transceiver Macrocell Interface (UTMI), and etc. These peripheral devices are connected with USB host to achieve all kinds of transactions disposing of USB 2.0. On developing USB 2.0 peripheral device IP core, how to test and verify the correctness of verilog HDL codes of these designed peripheral device chips is a problem that must be solved. Combining with actual project, this paper presents a set of detailed methods which make use of SmartModel tool and some developed tasks to design a test and simulation system for USB 2.0 peripheral devices IP core, proponed methods were involved with circumstance setup, command use, test module design, all kinds of transactions disposing such as IN type, OUT type, SETUP type, SOF type, additional tasks developing, and etc. Simulation results show these methods are valid, so can offer the reference for development of USB 2.0 system in all kinds of instrumentations and devices.

In multimedia system, some digital display devices often are adopted. At this time if still select conventional analog interface, digital signal from person computer (PC) need be switched twice by D/A and A/D, lost of video signal will emerge, so a kind of new interface, DVI technology often need be studied. Combining with real project, this paper introduces the detailed development methods of Digital Video Interface (DVI) transmitter and receiver in multimedia systems. These include the arranging of the architecture of Digital Video Interface (DVI) transmitter and receiver, the design of encoder and decoder circuit, clock recovery circuits, and etc. in addition selecting and designing of all kinds phase locked loop in hardware system were discussed in detail. These can offer a kind of reference method for developing of Digital Video Interface (DVI) transmitter and receiver video processing hardware in multimedia Systems.

Universal serial bus 2.0 systems consist of USB host control chip and equipment interface control chip, i.e. peripheral device chip. The traditional USB developing is only to develop USB peripheral devices, USB2.0 peripheral devices IP core has great application foregrounds. In USB2.0 system, peripheral devices are connected with host to achieve all kinds of transactions, such as bulk, interrupt, control, and isochronous transactions. How to detect and simulate signals of designed USB2.0 peripheral devices IP core system is an important problem. Combining with actual project, this paper presents a set of detailed detecting and simulating methods for signals of USB2.0 peripheral devices IP core system, which include signal analyzing, circumstance configuring, modules designing, state machines developing, and detecting and simulating methods of main signals, such as SYNC signal, EOP signal, PID signal, NRZI decoding data signal, CRC signal, and some main signal packages. Application results show these methods are valid.