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A direct sequence spread spectrum (DSSS) signal is commonly used in inter-satellite link (ISL) in navigation constellation; however, acquisition is a challenging task because of large-scale relative movement between satellites. In general, a signal search (carrier frequency and code phase) is implemented using two-dimensional partitioned fast Fourier transforms (FFTs), which is limited by the memory...
In this paper, the forward and inverse kinematics of a robot manipulator named RV-M1 are analyzed. The forward kinematic model is based on the DH parameters, and the inverse one is derived in closed form. Then, the interactive simulation system is established using MATLAB software which is one of the most used platforms for the modeling and simulation of robot systems. Finally, the simulation results...
When the nonuniform pulse-train signal is applied to the problem of weak target detection, the traditional long-time integration methods based on FFT are no longer valid. A novel method based on Keystone transform and nonuniform FFT is proposed here to accumulate the echo energy, wherein the former is employed to remove the range walk and the latter realizes the coherent integration of nonuniform...
Level set methods have been extensively used in contour recognition and image segmentation. The traditional level set methods require to initialize the level set function regularly and are strongly dependent on initial contour position thus there are many problems about the methods. Considering those problems, this article proposed a new level set method to draw geometric active contour self-adaptively...
The existing study and application of Prolate Spheroidal Wave Function (PSWF) primarily around the characteristics of PSWF in a single energy domain, the characteristics of PSWF in two-dimensional time-frequency energy domain have not been mining and using, from the perspective of signal time-frequency distribution, Wigner-Ville Distribution with higher time-frequency resolution was introduced to...
Traffic flow detection is an important topic in intelligent transportation systems (ITS). At present, most of the traffic flow detection method for nighttime are based on the headlights. However, headlights are not available in bad weather while the vehicle taillights have more stable features such as colors. so that in this paper, a novel method based on vehicle rear lamp and virtual coil is presented...
Electrogastrography (EGG) is a noninvasive technique to record the gastric electrical activity. In recent years, researchers have proved that EGG has great clinical potentials to evaluate the gastric disorders. However, it has still not been used in clinic to diagnoses of diabetic gastroparesis or some other disorders. One of the reasons of this can be related to methods using for EGG signal analyzing...
This paper proposes a recognition approach for Semaphore flag signaling (SFS). We use the improved convolutional neural network (CNN) to classify the SFS. In the experiment we made Semaphore flag signaling system (SFSS), which based on CNN. The image can be directly input into the SFSS. Each alphabetic character or control signal is indicated by a particular flag pattern. We shoot the SFS videos by...
Existing quality assessment methods of contrast-distorted images have excellent performance by obtaining information of reference images. However, in actual life, there are not any reference images. To deal with this problem, we propose a simple yet promising no-reference quality assessment algorithm based on the human perception features for contrast-distorted images. First, human visual perception...
Blind deblurring attempts to recover the latent sharp image from a blurred one. Such task is a well-known ill-posed inverse problem and is therefore usually solved as a posteriori probability estimation, incorporating prior information on natural images. In this paper, we propose a general blind noisy deblurring model based on hyper Laplacian (HL) in gradient domain and kernel spectra prior. This...
A non-cooperative source localization method utilizing the time difference of arrival (TDOA) of a rotating short baseline on a single observer is proposed in this paper. The localization bias caused by constant TDOA measurement bias is analyzed. It can be proved that this localization bias can be auto-eliminated when the sum of baseline orientation vectors that correspond with all TDOA measurements...
By the effect of stratospheric winds, the position and attitude of high altitude platform are in the quasi-stationary state. This paper describes and discusses the swing state of the platform and on this basis, establishes antenna beam coverage geometry model, analyzes the impact of swinging state on handover. the average and maximum handover probability of the different tier cellular have been deduced...
Magnetically Mediated Thermoacoustic imaging (MMTAI) is a noninvasive imaging approach for electrical impedance. It collects ultrasound signals induced by thermal expansion to reconstruct the conductivity of the object with high spatial resolution and high contrast. Previously reported experimental results on MMTAI only were obtained from the high conductivity samples like the metal. In the study,...
Longitudinal rip of conveyor belts is a serious threat to safety production. Based on the machine vision technology, an algorithm used to find longitudinal rip of belts on-line from gray belt images directly is proposed. A gray image is first translated into a unidimensional vector. The unidimensional vector is further analyzed to obtain rip eigenfunctions. Then, faults of longitudinal rips are diagnosed...
Thyroiditis is a health disorder and it refers to “inflammation of the thyroid glands”. Once a thyroid nodule has been detected (or suspected), the first test that is routinely being performed is the fine needle aspiration (FNA) biopsy (invasive). This test result is helpful in the classification of the nodule being benign or malignant with the aid of bio-markers. Another common test is the Ultrasound...
Detecting infrared pedestrian in outdoor smart video surveillance is always a challenging and difficult problem. Although there have been many methods based on histograms of oriented gradients (HOG) to solve this problem, they would probably fail because of shelter and poor quality of image. To overcome this problem, we propose a robust feature to describe pedestrian which is called entropy-edge weighted...
With regard to the problems of traditional sparse array antenna imaging approach, since azimuth sampling insufficient of echo signal, it will cause poor resolution such as low resolution, serious main lobe expansion and side lobe jamming, 3D imaging approach of sparse array antenna based on compressed sensing is proposed. Based on Linear array antenna mode, sparse banded observer is designed, and...
Comparing Unmanned Aerial Vehicle (UAV) video image patches is a fundamental task in UAV video image processing. The main difficulty lies in the wide variety of appearance changes in images taken under different UAV imaging conditions, such as jitter, changing points of view, frequent undefined motion, illumination changes and etc. The usual algorithms which are based on the hand-craft features and...
The patterns of Human Epithelial type 2 (HEp-2) cell provide useful information for the diagnosis of systemic autoimmune diseases. However, the recognition of cell patterns requires manual annotation by experienced physicians, which is subject to inter-observer variability. Therefore, an automatic diagnosis system is desirable. As the crucial pre-processing step for cell pattern recognition, the performance...
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