With the widespread use of UAVs in daily life, there are many sensors and algorithms used to ensure flight safety. Among these sensors, lidar has been gradually applied due its stability portability. However, actual application, changes position with movement UAV, resulting an offset detected point cloud. What's more, when works, it scatters laser light from center surroundings, which causes cloud be externally sparse dense inside. This uneven density is difficult cluster using common...

With the rapidly incremental demand in electronic devices, there is something exploring multifunctional RF systems for reducing cost, minimizing radar cross and probability of intercept, etc. This paper presents an integration system communication based on DSSS (direct sequence spread spectrum) technique, attractive technique which highly secure robust. It utilizes different PN code to spectrum data avoid jamming mutually. Additionally, it uses BPM gain better performance. The simulation...

Real-time and stable positioning data is essential for the UAV to perform various tasks. The traditional multi-sensor fusion algorithm needs know measurement noise of sensor data, even if there are corresponding adaptive methods estimate noise, most cannot deal with time-varying noise. In addition, algorithms usually complicated, causing a large amount calculation. this paper, multi-sliding window classification unscented Kalman filter (MWCAUKF) method timestamp sort updating was proposed,...

Abstract Three different polyethylene/polypropylene (PE/PP) blends were microcellular foamed and their crystallinities melt strengths investigated. The relationship between crystallinity, strength, cellular structure was studied. Experimental results showed that the three had similar variation patterns in respect of structure, these correlative for each blend. For all blends, strength PP melting point initially heightened then lowered, crystallinity first decreased, increased as PE content...

The diesel engine combustion process is mainly controlled by the fuel injection characteristics, which will have a direct impact on performance of engine, more flexible strategy development direction high pressure common-rail system. In order to obtain change law extra-high under variable strategy, and improve overall effect different post-injection parameters was studied self-designed experiment bench, relevant results were discussed analyzed. show that: with rise quantity, NOx...

In recent years, many scholars have carried out researchs on UAV digital twin from various aspects. However, the research is still in preliminary stage, and there are some problems, such as incomplete data model fusion, poor migration of algorithm policy, relation between virtual physical space, lack extensibility application scenarios. order to explore potential technology fields, this paper introduces into monocular visual navigation. Therefore, proposes a twin(DT)-based framework...

Advantage of high speed railway has been approbated in the world. But noise is more and serious. The higher car, bigger value then its harm evident. that passes to car body interior can considerably reduce ride comfort; exterior will be made area along railway, which strictly demands suffer heavily. Noise abatement reduction become one major research questions on design, manufacturing department environmental protection. paper analyzes types source producing mechanism, tests applying sound...

Abstract In this paper, a detection device for air bubbles, impurities and other defects inside the flexible connection of aviation aircraft canopy is designed. This mainly composed prism, industrial camera, lighting analysis software. The prism repeatedly optimized using light tools optical simulation software to achieve best imaging results. internal situation glued surface entire cockpit realized by stitching algorithm based on SURF with additional feature points images. At same time,...

As an important unsupervised learning method, clustering can find the hidden structures in data effectively. With amount of grows larger, large sets is a challenging task. Many algorithms have been developed to deal with small sets, but they are often inefficient when large. Meanwhile, most require some extra parameters as input, which may not be easy obtain practical applications. This paper proposed new algorithm called hybrid and parameter-free method (HPFCM). HPFCM able rapidly perform...

Infrared and visible image fusion can integrate the target information of an infrared spatial detail a to constitute fused image, which has more complete accurate description same scene than single image. In this paper, novel method using saliency detection based on non-subsampled shearlet transform (NSST) is proposed for fusion. Firstly, effectively highlighted NSST. Then, different rules are designed regions non-saliency regions. Finally, fuse obtained through inverse Experimental results...

The paper provides an efficient extrapolation algorithm to enhance resolution as well reduce sidelobes, which is based on ASR. processing of simple operate. Simulation experiments show the validity algorithm. Comparing Fourier method, proposed obtains better results.

Information theory and machine learning are inextricably linked have even been referred to as "two sides of the same coin". One particularly elegant connection is essential equivalence between probabilistic generative modeling data compression or transmission. In this article, we reveal dual-functionality deep models that reshapes both for efficiency transmission error concealment resiliency. We present how contextual predictive capabilities powerful can be well positioned strong compressors...

The simulation of the submarine battery charge process is an important part modeling, which especially a firm foundation for further optimization usage modules whole power system. In this paper, modeling strategy discussed in detail firstly, succession integrated algorithm both improved back-propagation neural network method and linear technology are used brought forward building model, finally outputs experimentation show us comparatively high precision.

Polarimetric synthetic aperture radar (SAR) plays an important role in surface parameter retrieval, forest height inversion, terrain classification and target recognition. In order to improve the Quantitative application of SAR image, paper presents a polarimetric calibration method using four calibrators correct crosstalk channel imbalance transmit receive channel. After process, we obtain accurate feature scattering information. A superresolution imaging applies on image for improving...