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New hybridization of PO, SBR, and MoM for scattering by large complex conducting objects

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Journal of Systems Engineering and electronics 2007年第4期18卷 726-730页

作者： Dong Chunzhu Geng Fangzhi Yin Hongcheng Wang Chao National Electromagnetic Scattering Lab. Beijing 100854 P. R. China dept. of electronic warfare AFRA Wuhan 430019 P. R. China

As a marked extension of the traditional MoM-PO （method of moment-physical optics） hybrid method, a new hybridization of PO, SBR, and MoM （MoM-SBR/PO） is presented to calculate the multireflection contribution in the PO region efficiently by introducing the method of SBR based on RDN notion, which avoids the time-consuming iterative procedure and the choice of proper Green＇s function. As compared with the traditional MoM-PO hybrid method, the calculation efficiency of the proposed method is greatly improved, and its validity is verified by numerical results.

关键词： the method of moment (MoM) physical optics (PO) hybrid method shooting and bouncing ray(SBR) EM scattering radar cross section (RCS)

A passive wireless surface acoustic wave(SAW)sensor system for detecting warfare agents based on fluoroalcohol polysiloxane film

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Microsystems & Nanoengineering 2024年第1期10卷 67-78页

作者： Yong Pan Cancan Yan Xu Gao Junchao Yang Tengxiao Guo Lin Zhang Wen Wang State Key Laboratory of NBC Protection for Civil Beijing 102205China Institute of Acoustics Chinese Academy of SciencesBeijing 100190China The School of electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China

Long-term monitoring of environmental warfare agengts is a challenge for chemical gas *** address this issue,we developed a 433 MHz passive wireless surface acoustic wave(WSAW)gas sensor for dimethyl methylphosphonate(DMMP)*** WSAW gas sensor includes a YZ lithium niobate(LiNbO_(3))substrate with metallic interdigital transducers(IDTs)etched on it,and an antenna was placed near the IDT.A DMMP-sensitive viscoelastic polymer fluoroalcoholpolysiloxane(SXFA)film was prepared on a LiNbO_(3) substrate,and mode modeling coupling was used to optimize the design *** sensor can function properly in an environments between−30℃ and 100℃ with humidity less than 60%*** the wireless transmission distance was within the range of 0-90 cm,the sensor noise increased with distance,and the stability was less than 32°/*** optimizing the film thickness of SXFA,a relationship was observed between sensor sensitivity and film *** the film thickness of SXFA reached 450 nm,the optimal value was *** a distance of 20 cm between the transmitting and receiving antennas,DMMP was detected at different concentrations with the developed WSAW gas *** lower detection limit of DMMP was 0.48 mg/m^(3),the sensitivity of the sensor was 4.63°/(mg/m^(3)),and repeatable performance of the sensor was confirmed.

关键词： film alcohol passive

Modeling and Parameter Optimization of Statistical Priority-Based Multiple Access Protocol

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China Communications 2019年第9期16卷 45-61页

作者： Siying Gao Ming Yang Hui Yu dept. of electronic Engineering Shanghai Jiao Tong University

The Statistical Priority-based Multiple Access Protocol(SPMA)is the de facto standard for Tactical Target Network Technology(TTNT)and has also been implemented in ad hoc *** this paper,we present a non-preemptive M/M/1/K queuing model to analyze the performance of different priorities in SPMA in terms of average packet loss rate and *** based on this queuing model,we designed a percentile scoring system combined with Q-learning algorithm to optimize the protocol *** simulation results show that our theoretical model is closely matched with the reality,and the proposed algorithm improves the efficiency and accuracy in finding the optimal parameter set of SPMA protocol.

关键词： SPMA queuing model Q-learning percentile scoring system

An Improved 3D SPIHT Coding for Hyperspectral Imagery Data Compression

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Chinese Journal of Lasers 2002年第4期11卷 67-71页

作者：闫敬文沈贵明胡晓毅许芳 The dept. of electronic Engineering Xiamen University Xiamen 361005

In this paper, an improved 3D SPIHT compression coding method, naming 3D BCSPIHT, based on wavelet zero tree compression coding (EZW), is used to exploit redundancy in 3D hyperspectral imagery data. The experimental results show that this method can obtain the compression ratio 200 for 224 spectral band data without any K L transformation (KLT) to remove the spectral correlation, and the total compression performance of this method is better than the method of KLT and other two dimensional transformation (such as 2D DCT and 2DWT) to remove the spectral correlation and spatial redundancy. To compare with the total compression ratio of KLT+JPEG method and KLT+BBZTC method, this method reaches 200 folds at the average PSNR of 32.531 dB. This method enhances 2～5 dB in PSNR at same compression ratio to KLT+BBZTC method, and the average compression rate improves above 15 fold.

关键词： wavelet transformation set partitioning in hierarchical trees (SPIHT) 3D bicube SPIHT (BCSPIHT)

Research on ambiguity resolution aided with triple difference

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Journal of Systems Engineering and electronics 2008年第6期19卷 1090-1096页

作者： Liu Zhenkun Huang Shunji dept. of electronic Engieering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

The ambiguity resolution in the field of GPS is investigated in detail. A new algorithm to resolve the ambiguity is proposed. The algorithm first obtains the floating resolution of the ambiguity aided with triple difference measurement. Decorrelation of searching space is done by reducing the ambiguity covariance matrix＇s dimension to overcome the possible sick factorization of the matrix brought by Z-transformation. In simulation, the proposed algorithm is compared with least-squares ambiguity decorrelation adjustment （LAMBDA）. The result shows that the proposed algorithm is better than LAMBDA because of lesser resolving time, which approximately reduces 20% resolving time. Thus, the proposed algorithm adapts to the high dynamic real-time applications.

关键词： carrier phase measurement integer ambiguity triple-difference measurement decorrelation.

INTELLIGENT RESOLUTION OF COOPERATIVE CONFLICT

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Chinese Journal of Aeronautics 2000年第1期13卷 24-28页

作者：李林森于海勋罗继勋佟明安 dept. of electronic Engineering NW Polytechnical University Xi'an 710072 China

First, the concept of cooperative conflict is presented, and the characteristic of cooperative air combat is researched. Then, four methods of conflict resolution are designed by way of the first order predicate logic, i.e., link-up, coordination, accommodation and integration, and corresponding examples are given. A 2 vs 2 air combat simulation was carried out; after conflict resolution, the loss ratio is dropped to 0.54 from the original 1.32, so the enhancement of effectiveness is notable. The present research findings are that the wide conflicts discover the essence of multi-fighter cooperation, i.e., to as fully as possible enhance the effectiveness of each fighter to attain global optimization, and that the possibility of conflict resolution shows the application prospect. The proposed method in this paper is a helpful try to the application of the Fifth Generation Computer in the new generation of C3I system.

关键词： Algorithms Artificial intelligence Computer simulation Flight dynamics Knowledge based systems Logic programming Optimization

GPS dynamic cycle slip detection and correction with baseline constraint

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Journal of Systems Engineering and electronics 2009年第1期20卷 60-64页

作者： Liu Zhenkun Huang Shunji dept. of electronic Engieering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

When the cycle slips take place in the attitude determination of a moving platform, the precision of the attitude will be impaired badly. A method of cycle slip detection and correction is proposed, which is suitable to the dynamic measurement using GPS carrier phase： the cycle slips detection is first achieved by triple difference observables, then the cycle slips correction is performed with baseline length constraint. The simulation results show that the proposed method is effective to the dynamic cycle slips problem.

关键词： dynamic cycle slip dectection triple difference observable baseline constraint attitude determination.

Narrow-band interference excision in spread-spectrum systems using new N-sigma algorithm based on fuzzy threshold

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Journal of Systems Engineering and electronics 2009年第1期20卷 20-26页

作者： Feng Jining Wu Siliang Wang Ju dept. of electronic Engineering Beijing Inst. of Technology Beijing 100081 P. R. China dept. of electronic Engineering Hebei Normal Univ. Shijiazhuang 050031 P. R. China

The key to narrow-band interference excision in frequency domain is to determine the excision thresh- old in direct-sequence spread-spectrum （DS-SS） systems. The excision threshold is a non-linear function related to the number and the power of interference, and attempting to get the exact relation of threshold related to the number and the power of interference is almost impossible. The N-sigma algorithm determines the excision threshold using subsection function; however, the excision threshold determined by this method is not exact. A new method to determine the threshold of N-sigma algorithm is proposed. The new method modifies the scale factor N by use of the membership function. The threshold determined by this method is consecutive and smooth, and it is closer to the fact than that of the initial N-sigma algorithm. The GPS signal and single-tone （CW） interference （that is, typical narrow-band interference） are implemented in the simulation, and the results are presented to demonstrate the validity of the new algorithm.

关键词： direct-sequence spread-spectrum systems adaptive frequency domain interference suppression fuzzyfunction GPS signal.

Rules-based object-relational databases ontology construction

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Journal of Systems Engineering and electronics 2009年第1期20卷 211-215页

作者： Chen Jia Wu Yue dept. of Computer Science Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China dept. of electronic Engineering Univ. of California Irvine CA 92697 USA

To solve the problems of shaving and reusing information in the information system, a rules-based ontology constructing approach from object-relational databases is proposed. A 3-tuple ontology constructing model is proposed first. Then, four types of ontology constructing rules including class, property, property characteristics, and property restrictions ave formalized according to the model. Experiment results described in Web ontology language prove that our proposed approach is feasible for applying in the semantic objects project of semantic computing laboratory in UC Irvine. Our approach reduces about twenty percent constructing time compared with the ontology construction from relational databases.

关键词： ontology constructing semantic objects object-relational databases rules ontology Web ontologylanguage.