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To study the advance distance of guide signs of expressway exit, we divide driving behavior in expressway exit into five processes according to the characteristics of the driving psychology principle and drivers' response to signs. A model of guide signs of expressway exit is built to calculate the advance distance of guide signs that meets safety and comfort requirements. The proposed model is established on the basis of the insertion gap travel distance model and isokinetic deviation sine curve model of vehicle lane changing distance. Through the analysis of the setting mode of guide signs, we calculate a reasonable distance for guide signs under different road conditions and different driver characteristics. The proposed model is developed with the UC-win/road and simulated by the Forum8 driving simulator. Simulation results show that only the distance of the advance signs of a two-way four-lane expressway exit is close to the specified value of Road Traffic Signs and Markings, which is reasonable; while for expressway with six lanes and above, the specified value is small.

Choice-making in diverging in an interchange is affected by multiple external factors. Along with an analysis of the characteristics of drivers' choice-making in expressway interchanges, this study settles many other fundamental variables, including the selection tree, utility function, speed of vehicles on the main line, accelerated speed, hourly traffic volume of the ramp, time headway in the deceleration lane, and type of vehicle, etc. The two-level nested-logit probability model for drivers accepting ramp diverging and drivers' diverging choice behaviors modes is established. Based on the radar tracking data of part of diverging areas of interchanges in Guanghe expressway, the model parameters are estimated by the phased estimation method.According to t-test result, the influence degree of the characteristic variables is judged and the model is optimized. Results suggest that the choice behaviors of diverging at interchange is affected by multiple factors comprehensively, the two-layer nested logit probability model is featured by a higher prediction accuracy.

In this paper, a camera ranging method for agricultural robot localization in arable farming is described. Three calibration objects in different directions in the field are set. The distances between the robot are calculated, and the calibration objects are used the camera to obtain the robot position. The benchmarking procedure in Matlab includes image binarization of the calibration object and the curve fitting method was used to establish the relationship between the pixels number of the calibration object and the actual distance. The verification results show that the relative error of ranging is less than 1.5%. Furthermore, the camera ranging method for agricultural robot localization is proved to be easy and feasible.

This paper designed the posture initialization calibration method by the inertial sensor in human limb movement with any attitude toward. By initializing the target specific actions can be implemented to identify timing corresponding sensors and joint, and calculate the coordinate transformation relation of human skeletal coordinates corresponding to each inertial sensor's coordinate system and the 3D human skeleton model. Then through the coordinate conversion of inertial sensor attitude coordinates and depth first traversal calculation on human skeletal tree, real-time update of human motion body attitude data, driven simulation of human skeletal model by human motion, realize the real-time tracking of motion capture.

An automatic watering controller with AT89S52 single-chip microcomputer was developed. According to the moisture condition detected by soil moisture sensor, the system could control the watering quantity by using fuzzy control rules to limit opening and closing time of electromagnetic valve of the irrigation system. Mamdani inference algorithm was employed as fuzzy control model for this closed-loop control system. Soil moisture sensor was put into the substrate for roots growth to obtain moisture information and used as the input. By comparing the water needed for plant growth, water demand and the electromagnetic valve opening and closing time was determined by the single-chip microcomputer program. Centroid method of defuzzification was used to determine the quantitative level of watering quantity. This fuzzy controller was designed by MATLAB fuzzy logic toolbox. The control system was simulated by Simulink. Simulation results show that this control method has good stability.

A variable rate fertilizer application system with ARM microprocessor as control core was developed. The structure and realization principle of the system were introduced. The system consists of two velocity sensors of photoelectric encoder and proximity transducer, an ARM controller, and an executive unit of stepper motor. The system has automatic and manual variable rate fertilization modes. In the automatic mode, the system can be positioned automatically without GPS, and controls the stepping motor’s rotational speed according to the fertilizing amount in different grid to realize variable rate fertilization. In the manual mode, the controller combines the fertilizing amount in different grid input manually through the keys with the velocity of the applicator, and calculates the stepping motor’s rotational speed to realize the variable rate fertilizer application. The applicator working status can be seen in LCD on the controller. The experimental results show that the system can work properly.

The diagnosis of carpal tunnel syndrome (CTS) is based on a combination of characteristic symptoms and electrophysiologic abnormalities. However, the electrodiagnostic examination remains an expensive and time-consuming procedure. Therefore, more investigators have reported on their experiences on CTS diagnosis with ultrasound image. CTS is generally attributed to external compression of the median nerve. Thus, distinguishing the median nerve shape from speckle-obscured ultrasound image provides a potential for the diagnosis of CTS. To lower the speckle interference, we propose a novel compound imaging strategy to reveal the significant signatures of median nerve. We observed that patient's fingers motion in ultrasound imaging deforms nerve shape and produces tissue movement. Based on speckle decorrelation of image under different fingers motion conditions, speckle variations can be reduced by compounding technique. The primary assumption of compounding is that the ensemble average of a speckle image is the same as the incoherent average of the original object. In this study, the multi-level block matching and block sum pyramid integrated algorithms were adopted for speckle tracking and compounding between ultrasound images. The results indicate that the efficacy of speckle reduction is clear and the positions of the two median nerve boundaries are unchanged. In particular, the internal punctuated echoes of medial nerve become more distinct.

A method though the combination of a phase array plate and linear interpolation has been used to substitute phase-shifting, where effect of nonlinear interpolation is neglected. In this paper we mainly study the effect of non-linear interpolation in a phase array plate. The results of reconstructed image under several nonlinear interpolations such as cubic and nearest interpolations are given and are compared with those of linear interpolation and standard interpolation. Because only one hologram is needed in our method, it can be used in real-time measurement of a moving object.