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In this article, seven filter algorithms were compared. The Lee sigma method was more suitable for estimating soil moisture (SM) than the other filtering methods under different land cover types. First, we used a combination of roughness and the dual-polarized Sentinel-1A backscattering coefficients (VV and VH) to estimate SM in bare soil areas. Second, we employed water cloud model (WCM) to remove the influence of vegetation signals on the land surface backscattering and estimate SM in vegetation-covered areas. SM was also retrieved by modified soil moisture monitoring index (MSMMI) and modified perpendicular drought index (MPDI) of Sentinel-2A images. The results show that MSMMI can more accurately monitor SM in bare soil areas, which was slightly better than synthetic aperture radar (SAR) results. The SAR backscattering coefficients after the removal of vegetation influence by WCM can more precisely estimate SM in vegetation-covered areas, which is significantly better than MSMMI and MPDI, especially in high vegetation-covered areas. Optics and SAR differ in their abilities to estimate SM under different land cover, but the powerful fitting ability of machine learning can make full use of their advantages. We employed the generalized regression neural network (GRNN), support vector regression (SVR), random forest regression (RFR), and deep neural network (DNN) algorithms to estimate SM combining Sentinel-1A with Sentinel-2A images. The estimation accuracies of SM by regression algorithms were higher than those by the semiempirical SAR and optical models. The accuracy of estimated SM by DNN was higher than that of GRNN and RFR, which were better than SVR.

This paper uses the statistical data of Shandong Province from 1990 to 2016 to empirically analyze the interaction mechanism between rural financial development degree and agricultural industry optimization. The research results show that the scale of financial development, financial efficiency and density range have significant effects on the optimization of agricultural industrial structure, and there are obvious time characteristics. Shandong Province should increase the financial support of the agricultural industry, rationally allocate input resources, and attach importance to the interactive role of financial and industrial development.

In this paper, a fast simulation algorithm is presented for creating radar images based on shooting and bouncing rays. In this method, three-dimensional models of man-made objects are illuminated by a virtual SAR sensor whose signal is approximated by rays sent through the model space. Rays can be followed for multiple reflections within the object scene. SBR is adapted to calculate the contribution of each ray. By summing the contribution of each ray on the radar image plane, a radar image is obtained. And by clustering rays owning the different paths, the echoes from different components is separated. By this way, we can establish relationship between target components and the strong scattering source, thus it can provide an effective approach to analyze the complex SAR images and target characteristics. The developed method was implemented to calculate the radar image of the Slicy model, and the result is compared with the measured solutions. The results show that the simulation can provide very valuable information to interpret complex SAR images or to predict the strong scattering source.

A novel procedure is proposed to estimate the two-dimensional (2-D) velocity parameters of moving targets from single-channel synthetic aperture radar (SAR) data in a long-time coherent integration for motion compensation. First, the SAR data is divided into several sub-band data by sub-aperture decomposition, since target motion may be changing in the whole long-time aperture, so that the velocity estimation for each sub-band can be performed respectively. Then, the range walk correction is carried out via Doppler centroid analysis based motion estimation and compensation, by which the energy of the moving target is concentrated into a single range cell. This processing is especially advantageous to the following exact Doppler parameter estimation. Finally, the fine 2-D motion parameters are estimated based on mismatched compression simultaneously. Compared to conventional algorithms with a time-consuming searching process, the 2-D velocity estimation of moving targets can be carried out using this algorithm more efficiently, and the SAR image can be well focused and right located after further motion compensation. Experimental results for numerically simulated SAR images demonstrate the effectiveness of the proposed technique.

To diagnose the engine fault quickly and effectively, we purposed a method to engine diagnosis, based on Twin Support Vector Machine. This method utilized five exhaust gas parameter values of HC, CO, CO2, O2, NOX and normalized them. Then it took these data as feature vector for test and train in Twin Support Vector Machine classifier, so as to achieve the purpose of identifying fault categories. The experimental results shows that twin support vector machine have better effect than Neural Network or Support Vector Machine, and the training speed is faster. In the case of small sample data, the accuracy rate of fault diagnose can reach 97.6%, which can effectively describe the complex relationship between the changes of vehicle exhaust components and engine default.

Drought occurs frequently in the world and it has great influence on the crops. Satellite remote sensing has been widely used in drought monitoring because of its wide range, fast information and short cycle. Temperature vegetation dryness index based on NDVI-T s space is widely used to assess drought conditions. In this study, LAI-T s space, constructed from MODIS MOD15A2 and MOD11A2 products, was used to replace the NDVI-T s feature space and drought condition of winter wheat in Henan province was evaluated from February 26 to June 1 during 2000–2015. The results show that there is a negative correlation between TVDI and soil moisture and LAI-Ts space can be used to monitor drought status. The LAI-T s feature space is a triangle in the low vegetation cover and evolves into a trapezoid with the improvement of vegetation cover. Drought is mainly distributed in the Midwest, southwest and northern regions in Henan province.

Change of Lake Area and water level reflects the space-time change of water resources objectively. Using LEGOS HYDROWEB lakes information data to extract water area and water level was not widely used. This paper use LEGOS HYDROWEB data of Qinghai-Tibet Plateau in the period of 1995–2014, 62 typical lakes water level change trend and 58 lakes area change tendency were analyzed, and according to its change trend these lakes can be divided into three types: growth, stable and recession, selected two typical lakes of each types for specific analysis. The results showed that the number of water level in growth type was 50, stable type has 9 lakes, and recession type has 3 lakes. The number of Area of growth type was 47, stable type has 9 lakes and recession type has 2 lakes.

Based on the antenna radiation theory, the universality, detectability and main characteristics of linear non-uniform electromagnetic wave are analyzed. When an object is illuminated by a linear non-uniform electromagnetic wave, there exists special phenomenon, such as induced eddy current and so on. Meanwhile, the definition of scattering function illuminated by a linear non-uniform electromagnetic wave is given. Computed by the method of moment (MoM), it is shown that the scattering characteristic of a metallic plate illuminated by a non-uniform wave is totally different from that by a uniform plane wave, and the peak magnitude is even bigger, which sufficiently demonstrates the significance of linear non-uniform electromagnetic wave in material detection.

This paper based on Huojitu mine, in Daliuta Shendong mining coal mining-induced subsidence area reclamation test base of Amorpha fruticosa pilot areas for the research of microbial objects, dynamic monitoring of environmental mitigation HJ-CCD satellite remote sensing image data between 2009-2013 and effect of mycorrhizal inoculation on ground vegetation, and soil sampling experiments and site statistics and data for comparative analysis. Monitoring methods for remote sensing make up the disadvantage of consumption and trouble which by the method of statistic and the sampling profiling.

As we know, it's very difficult to describe clearly the near-field scattering characteristic, as its scattering condition in near-filed, namely, the spherical-wave illumination and non-uniform irradiation, is strictly relative to the distance. Also when carry out the measurement, it is necessary to get the related information of the calibrator. In this paper, basing on the surface reflection algorithm and edge diffraction equivalence theory, we derived equivalent correctional equations of the near-field RCS canonical calibration bodies. In the final, we compared the calculation results with the measurement's, which agree well with each other and shows that the conclusion can be used for the future work to effectively reduce the calibration error.

This article puts forward the third-party guarantee mechanism model with uncertain information. And proved in incomplete information conditions, Guarantee agencies charge premium and reverse collateral will change the profit function and reduce the income of SMEs. It makes partial lower risk SMEs who cannot provide counter-guaranty exit the credit-guarantee market, resulting in the appearance of credit guarantee paradox. The government financing subsidies will effectively relieve SMEs' credit risk. Through the scale amplification effect of loan guarantees, it improved the incomes of bank and guarantee agencies.

International regional cooperation has become an important way to countries to solve energy issues. In many regions the regional energy cooperation is an inevitable trend. But the complexity of regional energy cooperation, the progress of the regional energy cooperation is not smoothly. This paper by using the dynamic analysis method of evolutionary game, analysis the influence factors of the regional energy cooperation. And then does simulation by use the MATLAB, in order to test the conclusions of the evolutionary game model of regional energy cooperation. Then give some suggestions to the regional energy cooperation.

As a method to analyze the soil moisture, the NDVI-Ts space has aroused much attention. The paper uses the method of TVDI which calculated from the NDVI-Ts space to monitor the soil moisture status of Shendong mining area which is located in arid and semiarid area in Northwest China from 6 September to 8 November. The soil moisture status come from TVDI was consistent to the physiognomy types distribution. The west and southwest of mining area is desert beach corresponding to the area III (arid zone); the east and north-eastern of mining area is loess hilly region corresponding to area I (wet Area); in the northwest of mining area is mobile sand dunes and semi-fixed dunes, and in the south-east is typical grassland corresponding to region II (normal area). By carried out a linear correlation analysis between TVDI data and in-situ measured the soil moisture data in different depth of 0–5cm, 10cm, 20cm and 40cm, a significantly linear relationships (α0.05) existed. In the depth of 0–5cm, the linear relationship was even higher, reached 0.8201. The result showed that it was feasible to use the method of TVDI to dynamically monitor soil moisture.

Software is easy to change to compare with hardware systems because software is not constrained, as hardware, by the physical laws. Therefore Software Configuration Management (SCM) becomes paramount today to track, control changes in software to ensure that software is developed with limited budget, acceptable cost, and required time frame. In this paper, we concentrate on the evaluation of two popular configuration management tools: MS Perforce and Subversion. The evaluation follows a systematic evaluation procedure and the qualitative and quantitative results are carefully reported. The proposed and applied evaluation procedure can be reused for similar objectives.

The recent and rapid advances in hardware have led to an explosion of real-time and concurrent applications, especially real-time control system applications. This, in turn, requires practical software development with new technologies such as Object- Oriented Analysis and Design (OOAD), Model-Driven Development (MDD) with the Unified Modeling Language (UML) as the principle modeling language. In this paper, we apply the Rapid Object- Oriented Process (ROPES), to analyze and design a house alarm system. The case study spans all the typical software development phases, from requirement analysis, analysis, to design. Our modeling experience demonstrated that ROPES is an appropriate approach for the analysis and design of real-time and concurrent control systems.

As a non-contact automatic identification technology, radio frequency identification (RFID) technology plays an increasingly important role in social life. But the existence of potential safety problems has restricted the widespread application of RFID technology. In order to deal with the design challenges in the calculation of speed, communications capability and storage space to the low-cost radio frequency tags, this paper illustrates a new secure communication model based on the existing RFID security protocols. Through comparing and analyzing of the existing RFID tag security policies appeared in many papers, a new lightweight encryption algorithm (LEA) has been proposed based on the criterion of block cipher, especially the improving DES encryption algorithm. It does not require complex computing and high-strength encryption technology. The core components S-boxes are redesigned and implemented on FPGA in this paper, and the security performance of S-boxes is proved through the analysis of probability and statistics. This algorithm can effectively enhance the security in the low cost RFID system.