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A wideband and circularly polarized (CP) substrate integrated cavity-backed patch antenna is proposed. This antenna has a wide-beam radiation pattern. The half power beam-width (HPBW) is 154° and the axial ratio (AR) below 5.8dB is more than 229° in both $\mathbf{phi}=\pmb{0^{\circ}}$ and $\mathbf{phi}=\pmb{90^{\circ}}$ planes, which has a large potential for CP wide-angle scanning phased array. The impedance bandwidth with SII $ is more than 23%. An $\pmb{8 X 8}$ planar phased array based on the antenna element is designed. The simulated results show that the main beam can scan from -60° to + 60° with 3dB gain fluctuation and from -80° to + 80° with 6.5dB gain fluctuation. Meanwhile, the AR is smaller than 3dB within the scanning range from -60° to + 60°, and smaller than 6dB within scanning range from -80° to + 80°.

Non-Functional (NF) requirement is very important for the success of a software service. Considering that there could be multiple services implementing a same function, it is crucial for software providers to understand the real NF demands from consumers so that they can meet these demands and attract users. It is also crucial for consumers to know what is being offered so that they can pose realistic NF requests. We address both issues here by proposing a NF requirement analysis and recommendation system which works for both providers and consumers. NF requirements from various sources are first collected, and then we apply the factor analysis technique to identify those independent latent factors which contribute to those observable NF values. Finally we use cluster analysis to summarize the popular NF demands. Our experiment result shows the effectiveness of this approach.

The data model is one of the core problems in the field of XML data management, but at present the research on management of uncertain data supporting multi-dimensional continuous random variables has been limited. An extended data model supporting multi-dimensional continuous random variables was proposed based on the existing model. The new model made the continuous uncertain XML no longer confined to express one dimension. In addition, queries about joint probability and conditional probability on the model were defined, The query strategy also can choose appropriate characteristic value calculation method according to different continuous distribution types, thus improve the query processing efficiency largely.

We have examined the relationship among job insecurity, organizational innovation climate, psychological capital, and employee creativity. Furthermore, we identified the mediator role of psychological capital, and the moderator role of organizational innovation climate. According to the research, job insecurity and employee creativity show a curvilinear relationship (an inverted V-shaped form relationship); with moderate job insecurity, employees have the highest creativity.

A miniaturized high frequency (HF) inverted-V log-periodic dipole antenna (LPDA) which is composed of thin metal wires and mounted over lossy ground is optimally designed using genetic algorithm together with numerical electromagnetic codes (NEC). The simulation results indicate that the optimized antenna behaves well in its operating frequency of 6–30MHz.

To investigate the effect of AP on tumor necrosis factor, interleukin −6 and Interleukin −8 during myocardial ischemia-reperfusion injury. Forty New Zealand rabbits were randomly divided into five groups(n = 8), sham group(group A), myocardial ischemia reperfusion group(group B), Complex Danshen tablets group(group C), AP low dose group(group D), AP high dose group(group E). The concentrations of serum TNF-α, IL-6, IL-8 were detected. The result shows that the level of TNF-α increased obviously in 30 minutes after myocardial ischemia and after reperfusion in groups C, D, E, but less than that in group B (P

Image fusion quality assessment method based on Error-sensitive Model was seen as the issue of the fidelity of the image signal rather than fidelity of image information.Because they didn't consider the human visual characteristics,they are inconsistent with the subjective evaluation.In this paper,based on SSIM algorithm,considering the fidelity of image information,it will combine the structural and content similarity of fused images and source images,use low-level visual perception information which contain luminance and contrast masking effects as the image content similarity weight,and the mutual information that fused image obtained from source image as the content information weight to calculate with the SSIM,proposes the quality assessment of image fusion based on image content and structural similarity IC_SSIM (Image Content based SSIM, IC_SSIM).The experiment results show that IC_SSIM algorithm is more consistent with human visual characteristics than PSNR,and is better than SSIM in resolution and accuracy.

In order to address the increasing complexity of electromagnetic environments and adapt to the demanding need of the integrative electronic warfare, it is necessary to study the integrative reconnaissance technology for radar and communication signals from single-platform. At present, the systemic study of integrative reconnaissance has just begun, and the automatic recognition of modulation types is a very important research area in this field. The exploration of the method presented us the following discoveries. First, it utilizes the duty ratio to separate the two types of signals; secondly, based on the excellent features of the second order cycle spectrum it gives the spectral correlation characteristics of the conventional communication and pulse compression radar signals using the CA method; then, we refer the characteristic parameter and allow signals to be automatically identified. The simulation results verify the feasibility and correctness of this method.

In modern aeronautical communication system, researchers find it hard to distinguish signals considering the fact that receiver intercepts various and overlapping band signals, so how to detect the desired DS signal from multiple signals becomes a problem in the aeronautics communication. According to the multiple antennas structure of the aeronautical communication, this technique gives us a new detection method of DS signal which is suitable for aeronautics communication and different from the traditional methods of multiple signals detection. This new method introduces the Independent Component Analysis Technology in the part of the Pretreatment to overcome a number of overlapping signal band and the cross-spectrum signal when it is difficult to be separated. This method also improves the DS signal detection and identification of parameters in the sequential parts, and enhances the recognition accuracy. Finally, the simulation results prove that the detection method is effective. If the decision parameters are adjusted appropriately, this method will also apply to other communication signals detection.

According to the system requirements, the multicarrier OFDM transmission scheme was proposed in Intra-Flight Data Link (IFDL) physical layer. Considering the anti-jamming vulnerability, the reliabilities of OFDM system were quantitatively analyzed under several burst interference. Combined with the convolution interleaving, (255,223)RS—(2,1,7) convolution concatenated coding that was proposed originally by NASA was applied in OFDM system to improve the performance of error correction. The simulation results show that, under certain Bit Error Rate (BER) the concatenated coding OFDM system could achieve effective coding gains in typical IFDL channel environments.

A frequency offset estimation algorithm for DTMB system based on signalpsilas second-order cyclostationary is developed. A unified structure of the method is given for diverse modes in DTMB system. Simulations show that this approach has good performance for both single-carrier and multi-carrier modes in AWGN and dynamic Rayleigh fading channel.

In this paper, a novel timing synchronization method based on phase rotation PN Frame Header for DTMB standard is presented. The combined one sample per chip hard-limiting digital matched filters (HL-DMF) and serial correlators are applied to the timing recovery algorithm. Multiple-dwell PN code detection engine is used, which gives much more accurate timing recovery in terms of lower false detection probability and lower probability of missing the synchronization signal. The hardware resource is substantially reduced, and more conducive to implementation and ASIC design. Simulation and hardware test show that both in the presence of Gaussian noise and in multipath fading channels, the performance is very good when using this method, particularly in the situation of the low SNR.

This paper proposes an improved GVF Snake-based method which is applied to Envisat ASAR images to determine the interested object's boundaries. ASAR images have a lot of noise and speckle. But different from other low SNR images, they are also full of texture. While using GVF snake model, the result of the gradient vector field in ASAR images becomes even worse. How to reduce the influence of the unimportant texture and the noise level while to preserve the image features is the key problem. To solve this, log Gabor wavelets that have the ability to preserve the phase data is introduced into the new scheme to correct the gradient vector flow. Results show that the new method can detect the contour of the interested object more accurately and false edges are removed.

Analog transmission has the advantage of allowing the quality of recovered data to vary gracefully as the channel conditions vary. For the purpose of robust image communication, two analog error-control coding schemes based on dimension-expanding Shannon mapping are discussed in this paper, including the encoding processes, decoding processes and joint source channel optimizing design methods. In addition, a method of getting the upper and lower bounds of the theoretically optimal coder is presented. In comparison with the optimal coder, these two analog error-control coders are easy to implement and simulations show that they both perform well and are robust to channel and source mismatch. It can be concluded that they are both good candidates for image subband coding to protect important source messages and suitable for robust image communication where channel conditions vary.

This paper proposes an optimized H.264 intra prediction arithmetic to reduce the time required to complete the intra prediction by saving ninety percent waste time during the process of intra prediction. Firstly, the 16times16 luminance prediction can be decomposed equally into 16 parts and inserted into the same macro-block's 4x4 luminance prediction to save the 16times16 luminance prediction time in one macro-block's luminance prediction. Then, by means of changing the computation sequence of 4times4 luminance prediction, a large amount of waiting time between 4times4 blocks' luminance predictions can be further removed. Almost all the waste time can be reused or eliminated by these optimizations. At the last part of this paper, an optimized hardware implementation aiming at fitting to the whole H.264 video coding system and a method to realize 16times16 luminance DC prediction on it are proposed.

For the application of airborne target drone, a distance measuring algorithm based on frame synchronizing code is presented. Taking the wireless data link of a airborne target drone for example, this paper elaborates the method that takes the synchronizing code of the data link frame in wireless telecontrol (TC) and telemetering (TM) as the measuring code, and gives out the principle of the measurement, the design of the circuit and the analysis of the error. Regarding the ground control station as the zero distance benchmark, comparing the radar identified flight data and the airborne target drone measured data, these two are well fitting in plot. Besides, the mean square error of the distance that airborne target drone measured is in range of 20 m, which meets the demanded error in range of 30 m. Many types of airborne target drones and many flight experimentations show that this method is simple, good-precision, low channel energy spent and low system cost. This method can also be applied to other wireless system that needs measuring continuously in range of 300 km