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Polarization characteristic is an important characteristic of radar target. Based on the electromagnetic modeling and calculation of foreign typical moving platform, the typical polarization characteristics of the coexistence of in-phase and orthogonal component in the return are obtained. And then combined with scattering matrix theory, it is proposed that the conventional generic scattering elements cannot reproduce the two components at the same time, and the necessity of the research on controllable polarization characteristics of scattering elements is demonstrated.

Silkworm cocoon species identification is a key technical link to realize the intelligent sorting of silkworm cocoons. In order to realize the rapid and accurate identification of some species of group cocoons, an improved YOLOv3 colony cocoon species detection model—CBL-YOLOv3 model is proposed. Taking macular cocoons, rotten cocoons and reelable cocoons as the research objects, the YOLOv3 model is improved: K-means clustering is adopted to obtain the aspect ratio of the prior frame of silkworm cocoons, the composition ratio in the loss function is designed, and the network structure of the model is also modified. The CBL-YOLOv3 model is tested from two aspects: visual effects and evaluation indicators. The test result shows that the detection effect of the CBL-YOLOv3 model is superior to the traditional YOLOv3 model in terms of accuracy and speed, which can meet the needs of real-time detection of group cocoons.

In view of the low degree of automation, high manual inspection threshold, and no objective quantitative indicators for the detection standards of the Y731 cohesion machine currently used in fiber inspection, a fully automated raw silk cohesion inspection method using line array camera for raw silk image collection is proposed. The system is composed of a synchronous multi-filament entanglement inspection device, a photoelectric counting module, a tool holder control module, a camera moving module, and an image processing module. After the threading is completed, the original thread image is automatically collected and saved. At this time, the tool holder will reciprocate and rub the thread after reaching a predetermined number of times and stop. The line scan camera collects images again and processes them, marks the cracking points and decides how many times to rub again until half of the cracks are reached, and finally save all the images for subsequent query. The test results show that the system can automatically complete the enclosing inspection process and realize electronic inspection, which greatly improves inspection efficiency and accuracy.

In order to study the near-field target characteristic of the radio fuse, an accurate near-field echo characteristics modeling algorithm based on Physical optics (PO) and physical theory of diffraction (PTD) and shooting and bouncing rays (SBR) methods is proposed to calculate the echo characteristics of fuse, including echo power and echo signal and RCS. This method fully considers the characteristics of near-field, such as the influence of antenna pattern, spherical wave irradiation, distance, polarization and so on. The main research work in this paper involves the followings: (1) Firstly, the expression of near-field irradiation field is presented as spherical wave propagation mode, which takes into count the influence of the near-field distance and spherical wave irradiation. (2) Establishing the system coordinate of antenna and the system coordinate of antenna local polarization, and then define the directivity function of near-field antenna to characterize the antenna pattern, local irradiation and near-field polarization conversion characteristics. (3) Introducing near-field polarization scattering matrix to unify the scattering characteristic components of different scattering mechanisms, and then calculate the echo characteristic of radio fuse by integrating those of the geometrical elements which are illuminated by antenna beam during missile target encounter. In addition, the proposed theoretical model in this paper is calibrated by actually-measured data. And the emulation results are with a good agreement with measured results. Finally, we consider a simplified missile model, and compute its echo characteristics under different antenna pattern and different distance and different polarization. The results show that scattering peaks correspond to the points of the wings of the missile. In addition, the results change obviously when using different antenna pattern. At the same time, the results are different under the different distance. Numerical results prove the proposed method high efficiency and preciseness. It would be especially valuable in engineering application.

As a typical and effective passive jamming, chaff has been widely used in electromagnetic countermeasures. The chaff cloud formed by the explosion of chaff bomb is one of the main ways to realize the self-defense interference of the aircraft and the ship target. Aiming at the two stages of chaff cloud formation process in this delivery mode: rapid dispersion stage and stable diffusion stage, the electromagnetic modeling method is studied. Firstly, the diffusion process and spatial distribution of chaff in the atmosphere are analyzed according to aerodynamics and stochastic theory; Then, the electromagnetic scattering calculation method of chaff clouds at two stages is derived respectively by using absorption theory and dipole radiation theory; Finally, the space varying RCS curve and the time varying RCS curve of chaff cloud are given by modeling and simulation. The simulation results are analyzed and some meaningful conclusions are obtained.

An one-dimensional plasma frequency and the electron collision frequency distribution inversion method is proposed, which combined the current density Laplace transform finite difference time domain division method and the genetic algorithm. Based on the calculation results of one-dimensional FDTD electromagnetic scattering, the spatial distribution of plasma frequency and electron collision frequency of plasma generated by a plasma generator are reversed. The complex relationship between the time and space cost and the calculated parameters are analyzed. The numerical results show that this method is correct, simple and easy to be parallel.

Complex resonance frequencies contained in target's late-time transient responses are independent of target aspect and radar signal's polarization only relate to inherent characteristic, such as, size and shape of the target. This paper introduced the Prony method and MPM, and make comparisons between them by using the reconstructed late time response to estimate the anti-noise performance. Then MPM method is chose to extract the poles of complex stealth target, the result shows that poles extracted from complex stealth target is also independent of aspect, and it can be used as a effective character of stealth target identification.

Frequency variation could cause resonance region's Radar Cross Section (RCS) changes in oscillation, which always has a couple of resonant peaks, and the resonant frequency is a useful index that can help target detection and tracking. This paper, which is based on calculated data, analyzes the relationship between the resonant frequency and a series factors, including the attitude angle, size, volume, etc.

Current mobile network architecture is constructed through introducing mobile IP protocol on the basis of IP network. On the one hand it cannot break away from the inherent limitation of IP network, such as no strong security, complex forwarding devices, lack of high expansibility and no QoS guarantee. On the other hand it brings some new problems due to the repair to IP network, such as the triangular routing problem. A new mobile network architecture based on vector network is proposed in this paper. The design philosophy of this architecture is to separate the name address and the switching address of the mobile nodes, so it can support node mobility inherently. Besides, this architecture also possesses many innovation characteristics. For example, soft handoff can be achieved through multi-path connection to improve the handoff performance.

Refereed/Peer-reviewed This paper conducts a probabilistic analysis of energy consumption of electric vehicle. In particular, the vehicle speed is controlled by a model predictive control (MPC) to follow given reference speed while minimizing energy consumption, and the battery is modeled by nonlinear dynamic equations. Speed tracking accuracy and energy economy of MPC speed control is evaluated on EPA Federal Test Procedure driving cycle, which is commonly used for city driving testing and includes an approximate driving distance of 17.77 km. Furthermore, to conduct probabilistic analysis, Monte Carlo approach is taken to simulate a total number of ten thousands of synthetic FTP driving cycles, each with different profile. Numerical results and conclusion are then drawn to confirm the robustness of MPC speed control and the environmental friendliness of electric vehicle. Insights on battery operations for maximum energy efficiency are also discussed.

In order to efficiently and robustly land more aircraft on two parallel runways, search the conflict-free and less-delay reroute for arrival aircraft, we plan to control arrival aircraft with a novel trajectory operation model named Multi-layer Point Merge System (ML-PM). In this paper, firstly the notional example of ML-PM system is introduced, the characteristics of its horizontal and vertical profiles are described. Secondly, according to the availabilities on two parallel runways, the positions of aircraft on sequencing legs, a trajectory reroute model is built. After that, the geometric relations for conflict detection in merging zones are analyzed in details. Furthermore, two tests with runway re-assignment on and off are compared to study the performances of proposed ML-PM system, the numerical results have shown that: 1) both tests could generate conflict-free trajectories, 2) average delay, average landing interval, and makes-pan could be reduced by runway re-assignment. The relative improvement for average delay is 36.36%, for make-span and average landing interval is 1.35% and 1.36% respectively. However, the average flight time, flight distance, fuel consumption and co(2) emission will increase due to runway re-assignment, the relative increases are 13.49%, 1.11%, 13.49% and 13.49%, respectively. After that, a detailed study about the runway assignment is done, the changes of different indicators are analyzed. Finally, the conclusion is made, ML-PM system shows a very positive ability to dynamically control arrival flows to land on parallel runways. Refereed/Peer-reviewed