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China Remote Sensing Satellite Ground Station (RSGS), whose satellite-ground communication missions include telemetry, tracking and command(TTC secondly, sub-problems are grouped by their solving complexity and the heuristic method or the mixed-integer linear programming (MILP) method is chosen adaptively to solve sub-problems. The method is applied to the actual operation system of RSGS and the rationality of the model and the effectiveness of the algorithm are proved in real cases.

This paper presents a novel LC voltage-controlled-oscillator (VCO) based on active inductor (AI). Taking advantage of equivalent RLC model of the AI, a novel tunable differential AI (DAI) is designed and used to act as the LC tank of the VCO. First, a tunable DAI with cascode-structure and current-mirror feedback networks is designed to achieve high quality factor $(\pmb{Q})$ and high equivalent parallel resistance (Rp). Then, the DAI is used to replace LC in VCO to realize good comprehensive performance of VCO such as low phase noise, low power consumption and high output power. Based on TSMC $\mathbf{0.18}\mu\mathbf{m}$ RF CMOS process, the novel VCO is verified by Agilent's Advanced Design System (ADS). The results show that under the supply voltage of 1.8V, the output power reaches up to −4.2 dBm, a frequency tuning range is in 1.126-2.713 GHz, and the phase noise at 1-MHz offset is −117.2 dBc/Hz. A power of only 13.6 mW is consumed.

A wide tuning range, low $\pmb{K}_{\mathbf{VCO}}$ and low phase noise VCO is presented in this paper by combining fully differential active inductor (DAI), switched capacitor array and MOS-based variable capacitors. The adoption of the DAI instead of spiral inductor in the LC tank reduces the phase noise of VCO due to high $\pmb{Q}$ value of DAI. The multiple tuning modes by tunable active inductor, switched capacitor array and variable capacitor make VCO have a wide tuning range of oscillation frequency and lower $\pmb{K}_{\mathbf{VCO}}$ . Based on TSMC $\mathbf{0.18}\mu\mathbf{m}$ CMOS process, the VCO is verified by Advanced Design System (ADS). The results show that the oscillation frequency can be tuned from 988MHz to 4601MHz with a wide tuning bandwidth of 129.3%, and the lowest phase noise is −116.88dBc/Hz at 1MHz offset, and the $\pmb{K}_{\mathbf{VCO}}$ is as low as 45-550MHz/V.

In this paper, the experimental research was done to 30 teenager table tennis players at Haidian District Amateur Sports School by the method of imagery training. The training effects of the imagery training method and the traditional training method were compared. The experimental results show that the athletes who adopt the imagery training method have significantly higher standard performance results and technical evaluation results than those who use the routine training methods. The results of SPSS 22.0 test show that they reach the significant level and can effectively improve the athletes' technical level and training effect.

An algorithm of video denoising based on spatial-temporal combination is proposed to improve the video quality. This algorithm can adaptively distinguish the still regions from the motion regions of video frames by bilateral motion detection of multiple frames, where temporal bilateral Kalman filtering is applied to the still regions and spatial bilateral adaptive Nonlocal means (ANL) filtering is applied to the motion regions. Experimental results show that by making full use of the spatial-temporal information of video, the proposed algorithm can significantly improve the peak signal-to-noise ratio (PSNR) and the subjective video quality without movement ghosting. Besides, the speed of video denoising can be accelerated by bilateral filtering.

This paper presents a method to reconstruct the three-dimensional model in monocular stereo vision. Depth can be obtained from monocular disparity in bifocus images. The stereo disparity results from lenses' separation during imaging. Besides, 3D information can be acquired with depth and camera intrinsic parameters by means of camera calibration. Based on the characteristics of bifocus imaging, this paper develops a new method to detect and match feature, which fits monocular stereo vision much better. With only a pair of bifocus images and a calibrated camera, three-dimensional model of scene is constructed successfully.

In this paper, we investigate the problem of efficient image data encryption and compression. Based on feedforward-feedback nonlinear dynamic filter (FFNDF) and employing random arithmetic coding, a novel image encryption scheme integrated with the set partitioning in hierarchical trees (SPIHT) has been proposed. The FFNDF is employed to generate pseudorandom sequences which determine the mapping the interval position in the process of arithmetic coding. By encoding the bits obtained from different passes in the SPIHT algorithm with adaptive random arithmetic coding, we obtain a flexible secure image compression coding scheme. Also, the scheme accommodates features of progressive coding of the SPIHT. Theoretical analysis and experimental results show that the scheme has good cryptographic security and perceptual security, and it does not affect the compression efficiency apparently. The efficiency and security of the encryption scheme makes it an ideal choice in various applications such as total encryption, selective encryption, conditional access.

Chaotic maps can be used in constructing hash function because of their properties, such as parameter-sensitivity and random-similarity. Many algorithms have been proposed for chaos-based one-way hash function. However, how to map bit strings into decimal number is ignored by these algorithms. The Analysis for a chaos-based one-way hash algorithm shows that it is a very important problem. Probably, selecting an inappropriate map will result in the collision of hash values. A non-linear map method is presented. The computing result shows that it is valid.

It is the key for an enterprise to improve the quality of IT outsourcing relationship to achieve success. This paper firstly makes analysis on the evaluation indexes of the quality of IT outsourcing relationship and its effecting factors, then puts forwards four tactics to improve the quality of IT outsourcing relationship, which are strengthening the convergence and integration during the outsourcing transition, enhancing the controlling mechanisms of outsourcing, promoting the building of trust mechanisms, and reinforcing the quality management of complex outsourcing relationship.

In this paper, a novel image encryption scheme based on chaotic maps is proposed. By combining XOR operations and circular bit shift operation, the security of this encryption algorithm is enhanced effectively. Two chaotic maps are adopted in the proposed scheme. One creates a binary stream for XOR operation, and the other creates some random numbers which are used to determine the circular bit shift. First the pixel values of the plain-image are modified randomly by the classical chaotic masking technique, namely XOR operation from the first block to the last block, and then the modified image is encrypted by the circular bit shit operation from the last block to the first block in the inverse order. The security of the proposed encryption scheme is detailed analyzed, and the experimental results show that the algorithm has a high security performance and a good efficiency.

The problems of signal detection and parameter estimation are of fundamental importance in detection and recognition of weak target. The typical problem is the measurement of the harmonic signal parameter in the noise. In traditional theory, the processing method is based on uniformly sampling and all the data have the same effect. This paper presents a novel theory to deal with the problem, which treats the data in a different way. The novel method is based on the sub-sampling technique. The position of the new sampling data is not regular in source sequence, but they have the same feature that they are affected by noise less seriously than those that are deserted. Since the new data is not uniformly sampled, the traditional estimation algorithm will be modified and a novel algorithm is discussed to deal with the sub-sampling data. The method presented in the paper offer the higher accuracy of the estimation, because the sub-sampling data have higher SNR. Computer simulations are used to obtain the parameter estimation performance results. Results obtained by this new method are compared with traditional FFT method, and the parameters obtained by new method are more accurate