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To improve the understable imaging system caused by the high work frequency of image composing circuit on a satellite,the structure of a camera was innovated.A composion and compression method of Time Delay Integration CCD(TDICCD) based on a Field Programming Gate Array(FPGA) platform was proposed for satellite remote sensing data.The principle of real-time compostion and compression for multi-channel satellite remote sensing data was introduced.Then,based on the characteristics of TDICCD linear array push-broom imaging mode,the improved JPEG-LS was used.By taking adaptive quantization to control the coding rate dynamically,composion and compression of image data were simultaneously achieved on the FPGA.At last,an experiment platform was established for the validation.Experimental results indicate that the system clock has reduced to 80 MHz and 64 MHz,respectively,from the original 100 MHz in the lossless and 2-time compression and the Peak Signal Noise Ratio(Reconstruct PSNR) of the image is higher than 80 dB.As the proposed algorithm has low storage capacity,the average processing time of one line image is 57.5 μs,smaller than the smallest line period of the camera.The proposed algorithm is stable and the system is reliable and achieves the composion and compression of multi-channel TDICCD remote image within the camera.

According to the stitching structure of CCDs in an Aerial Push-broom Remote-sensing Camera(APRC),an auto-focus method by using the image from the CCD overlapped sections was proposed.Firstly,the structure of CCD in the APRC was introduced.Based on the pushing-broom imaging characteristics,a Field Programming Gate Array(FPGA) which can process data in parallel model was used to receive the image data from multi-CCD overlapped sections and calculate the evaluation values of image quality at the same time.Then,three kinds of the CCD overlapped sections with the biggest evaluation values of image quality were selected as the gist for determining the focus direction.Finally,the feasibility of the method proposed was validated by an experiment.In the experiment,when the push-broom frequency is 10 kHz,the time for one focus step is 0.2 s,which illuminates that the proposed focusing method has good real-time ability,and it can offer a feasible gist for the on-track focus in the APRC.

A complete test equipment has been prepared for a TDICCD imaging system,being composed of power-supply simulation system,test-control simulation system,485 bus monitor system,image data collection system.The equipment has successfully been performed to cooperate with the development of someone remote-sensing camera.The experimental results indicate that this equipment works stably,high effectively and can meet the test requirements of TDICCD imaging system.

Based on financial information of listed manufacturing companies, the research aims at predicting financial distress using the integrated model of factor analysis and discriminant analysis to establish the model, and tests the prediction accuracy of the model. The results show that the model in this paper has higher discriminant precision, and it makes further explanation that the choice of financial ratios is very successful. Meanwhile, the predicted results confirm that the closer the time of financial distress, the more accurate the prediction effect.

Financial crisis is the most significant and comprehensive performance of enterprise crisis. From the empirical point of view, this paper sets up a financial evaluation index set for enterprise financial crisis. First, in-depth analysis of various financial indicators of listed companies is made to choose related index. Then taking all the listed companies as samples, fuzzy clustering is used to clustering the related financial indicators. And indexes in the same set are screening according to correlative index, with which formulate a scientific and operational financial evaluation index set of listed companies. Since the indicator set has covered effective information of the financial situation of the listed companies, it can be used to evaluate the financial information by a multidimensional array. So as to provide an empirical basis of financial crisis early warning system of listed companies.