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1PPS signal is the standard output of GNSS timing receiver. The pulse is used to synchronize the device to Universal Time Coordinated(UTC) or the GNSS system time, and it is the recovery of GNSS system time or UTC in the local timing receiver. 1PPS signal of GNSS timing receiver is often phase calibrated in discrete steps with an uncorrected frequency error present. If such a calibration was used in GNSS timing receiver, we would observe the 1PPS signal phase error progressing at the uncorrected frequency error. When the phase error grows to the phase step size, a calibration will be done and we will observe a phase step in the 1PPS signal phase. This phase step is GNSS Timing signal granularity. This phenomenon is called the sawtooth behavior of the GNSS 1PPS signal. In order to correct the sawtooth error of 1PPS signal, we study the zoom technique of GNSS timing signal granularity, and propose an improved scheme. The programmable delay line technology is introduced in the improved scheme. The granularity of the programmable delay line device can reach 0.25ns. Combining with the programmable delay line device, we propose a control algorithm which can realize the zoom of local 1PPS signal's granularity. This scheme allows for real-time correction of the quantization error and reduces the residual noise to about 1∼2 nanoseconds peak to peak (pk-pk), and improves the instantaneous and short-term timing accuracy of GNSS 1PPS.

This paper proposes a new thermal tactile slip device to detect the slip direction. The thermal changes caused by the relative sliding of two objects with different temperature are studied, and the ANSYS finite element method is used to simulate the thermal phenomenon. The device mainly consists of a thermostatic control circuit, a heat conduction layer, a heating layer and a thermal sensor array, as well as a temperature measurement circuit. And the thermal sensor array is especially designed to measure the temperature responses on the contact surface. Tests are performed by sliding the sensing device unidirectionally on a smooth flat iron. The results show that slip direction can be effectively discriminated by this proposed device. The performance of the device can be further improved by using more thermal sensor arrays to realize the omnidirectional detection.

Analyzing the pulse wave is an important method to diagnosis the status of human health. Generally the directly acquired signal contains varying degrees of baseline drift which is usually caused by breathing and physical movement, it mostly influences the accuracy of signal analysis and must be eliminated. This article presented a cascade filter framework to remove the baseline drift of pulse wave. The first stage zero phase filter (ZPF) roughly reduced the trend of the baseline drift. The second stage of the removed method considered the signal features. Through the pulse waveform reference points' accurate location and cubic spline estimation, we completely eliminated the rest drift. Compared with the other methods, e.g. wavelet-based filtering, morphological filtering, empirical mode decomposition (EMD) filtering, the experimental result showed that the proposed method had not only better effect, but also small calculation cost, and the scheme was more suitable for actual application.

Localization technology is a hot research point in the sensor network area. For low power consumption and long life characteristics of sensor nodes, sound location technology has its specificities using in wireless sensor network. In this paper we proposed a sensor network with sound position function, in which three sensor nodes with acoustic sensor have been used to detect trajectory of a small car. This paper selects digital signal processors as controllers and processors for wireless sensor networks nodes. The experimental results show that this approach can achieve a good positioning of moving targets.

A compact thermal tactile display device with multiple heat sources is proposed in this paper. The device has a 3×3 display units array and a Peltier module. In every display unit, a wire-twined resistance is used as heat component, a minitype NTC thermistor is used as temperature sensor, and an aluminum column is used as heat conduction component for contacting. The Peltier module is used to cool the display units array. Finally, the device was installed on the hand controller, allowing operators to manipulate virtual hand to touch the heat sources in the virtual environment, and its thermal tactile display property was tested. The results showed that the thermal tactile device can display the temperature from 5°C to 55°C, and different temperature field distribution can be displayed on the contact surface of the 3×3 array.

For data association problem during the multiple targets tracking in the Radar Network system, we proposed a kind of improved Discrete Hopfield Neural Network (DHNN) data associating method. We used the parallel computation and optimization ability of DHNN, and improved the global optimization ability of DHNN by modifying the energy function of DHNN and applying the simulated annealing algorithm to the status's adjusting of DHNN. This method improved the tracking performance and shortened convergence time of the net-work. From the Monte Carlo simulation experiments, the association performance and compute velocity of the proposed method was proved higher.

Fast variable surface temperature (FVST) can be used in sensor dynamic characteristics test and thermal tactile, and so on. In this paper, we design a Fast Surface Temperature Signal Generator(FSTSG), generating temperature with Peltier device, using infrared sensors to monitor real-time FVST, changing the power of Peltier device by voltage adjusting and changing voltage polarity by a bridge for fast change between heating and cooling. Also we design a heat exchange system to improve the performance of FSTSG. Test results show that, the FSTSG has a heating rate of 10°C/S and a cooling rate of −5°C/S in 5–50°C, the FSTSG can be used to produce temperature wave of square, triangular, and so on.

Current file-like data exchange methods of high-liquid securities information are mainly based on some high redundancy formats such as DBF, which wastes bandwidth resource and induces high disseminating latency. Besides, the file segmentation technique these methods adopt aggravates bandwidth overhead and causes extra latency. To solve the problem, this paper presents FFTP — an Extended FAST based high-liquid securities data exchange method. FFTP promotes high-liquidity in two aspects. First, by mapping records of the file-like data to FAST messages, FFTP can significantly reduce redundancy of exchange data by leveraging high efficiency encoding of Extended FAST, and thus bandwidth overhead can be reduced. Second, since the encoding procedure is based on the granularity of a record, the receiver can instantly decode records from a file segment and no retransmission of the whole file is needed, which effectively reduce latency of records of the received segments. We implemented the Extended FAST and the FFTP prototype. The experiments demonstrate while avoiding full file retransmission, FFTP can decrease DBF's size by over 70%, very close to some general-purpose compression methods such as bzip, gzip, rar, which verified the feasibility and effectiveness of the new method.

To introduce real materials into digital painting, the interactive digital painting system “Difpainter” is proposed. The rudiment of this system is the calculation of difference between images captured from video camera. The system first captures two images from video camera, and then calculates the difference of the two and yields foreground image, finally paint target image with the foreground image by alpha blending technology. This process is executed iteratively; the parameters are configured through graphic user interface. The system enables using webcam to practice “Light Painting” and some other novel painting skills. This research enriches the skills of digital painting, improves the user experience, and presents novel visual effects.

One novel technique to locate the partial discharge in the transformer is presented in this article, which is based on the modified multiple signal classification method (MUSIC). In this technique, the phased-array antenna is fixed on the shell of the transformer. After received by the array elements of the antenna, the signal from the partial discharge source will be analyzed by the modified MUSIC algorithm. Thus, orientation of one or even several partial discharge sources in the transform can be estimated. The result of emulator program shows that this modified algorithm has a very high precision and resolution, especially for the sources that are closely positioned.