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For narrow-band radars, the linear frequency modulation (LFM) signals are commonly transmitted to acquire the target information. This paper presents a new mono-pulse detection method of detecting the weak moving target in the sea clutter. The de-chirp operation, which is one concept in the wideband radar signal processing and used to reduce the sampling rate, is borrowed to process the noisy echo instead of the traditional matched filter. Then the stretched signal is analyzed by the short-time Fourier transform (STFT) in the time-frequency representation (TFR). Here we introduce the coherent-like integration in the TFR to improve the signal-to-clutter ratios (SCRs). Finally, the Neyman-Pearson criterion is utilized to realize the target detection. Compared with the traditional detectors, the experimental results on the raw data illustrate that our proposed method has a good performance.

with the rapid growth of online learning resources, users are facing the problems of information overload in the process of online learning. Improving information precision service has become the primary task of distance learning. The paper optimizes the research on the precise service technology and methods of distance learning using the big data analysis technology, and improves the pertinence and individuation of obtaining distance learning services, realizes the individualized teaching under the support of computer and network information technology, enhances the level of distance learning service and knowledge dissemination efficiency, and promote Internet plus education data service industry development.

With the rapid development of streaming media and cloud technology, new opportunities have been brought to the progress of network distance education. In order to solve the bottleneck problem of data processing, cloud computing architecture and mode are adopted to ensure the data processing ability of the platform. The design of distance learning platform based on cloud technology is given, and CDN (Content Delivery Network) and flash P2P (peer to peer) is used in the streaming media service system. The stability of data and the user experience effect is improved.

Agricultural intelligent decision system has a positive practical significance for guiding agricultural production, which can provide scientific basis for agriculture. Big data analysis technology can effectively improve the performance of intelligent decision system. The research development of the agricultural intelligent decision system is given. The classification of the agricultural decision system is introduced. The frame designation of the intelligent decision system is studied, and the design process is given.

Online learning resources growth speed is in geometric series with the rapid development of computer and communication technology. Users in distance learning and training process encounter the problems of information loss and resource overload, the main reason is that the distance learning system can't effectively understanding of teaching resources semantic information, different structure of teaching resources can't effectively organized into useful knowledge at present. In addition, the system can't provide personalized learning services for users according to different learning needs and backgrounds. How to quickly and effectively obtain the personalized learning information and learning resources from a large number of learning resources has become an urgent need for users. The CFR algorithm using combined similarity of user attributes and interest topics is proposed. Because of the problem of sparse matrix and cold start and in personalized recommendation, the paper proposes a CFR algorithm with combined similarity of user attributes and interest topics, and through experiment verify the algorithm validity.

the traditional remote data collection has the shortcomings such as the cover scope is small and the corresponding is unreliable, and the wireless network communication has better timeless and does not have the space limitation. The remote data collection and supervisory system based on GPRS/3G (General Packet Radio Service/The 3rd generation communication) network is discussed and designed in the text. It discusses chiefly a scheme which uses JZ4730 microcontroller to control TC35i module and make use of MMS (Multimedia Messaging Service) and SMS (Short Messaging Service) to complete remote data collection and supervision, and supplies a design program of the hardware and software, and then a conclusion is given at the end of paper.

The dynamics of spacecrafts with slewing payloads and flexible appendages are complicated, nonlinear, and coupling, which increase the difficulty of control. A new control scheme is presented for a type of flexible spacecrafts with slewing payloads. In the scheme, an adaptive fuzzy logic system (FLS) is designed to approximate the main dynamics of the plant, and an extended state observer (ESO) is introduced to observe and compensate the error of the FLS and quick-varying disturbances; at the same time, the output of the FLS is utilized to improve the performance of the ESO. The simulation results illustrate the effectiveness.