Research on channel-fixed delay error estimation of wideband digital array radar by Xiaobei ZHANG, Quan ZHANG, Ming FANG, Kun QIN, Qi ZHANG

“…A channel-fixed delay error estimation method was proposed to tackle the performance degradation of digital beamforming caused by the channel-fixed delay error of wideband digital array radar.First, the integer part of the fixed delay of the channel was estimated through the correlation integral peak of the baseband transmitted signal and the baseband received signal containing unknown delay parameters.Then, the fractional part of the fixed delay of the channel was estimated with parabolic interpolation by using the correlation peak and its adjacent two points.Finally, the multi-channel fixed delay error was calculated and compensated.The simulation results show that the multi-channel fixed delay estimation of wideband digital array radar can be realized on Xilinx xcku115.The estimative precision can reach 0.001～0.014 times the sampling gap when the signal-to-noise ratio of the input signal is 10～30 dB.The proposed method can meet the engineering application requirements and improve the performance of digital beamforming in wideband digital array radar.…”
Get full text

Person re-identification algorithm by image from video surveilance sistem using a neural network compound descriptor by S. A. Ihnatsyeva, R. P. Bohush

“…To obtain it, the average value of the k-nearest neighbors such features of a person’s image is calculated. The experiments performed indicate an increase in re-identification accuracy for the Market-1501, DukeMTMC-ReID, MSMT17 and PolReID1077 datasets.…”
Get full text

Efficient revocable attribute-based encryption scheme by Xuejun LI, Dan ZHANG, Hui LI

“…In the existing solutions,the time-based scheme is difficult to achieve immediate revocation,and the third-party-based scheme often requires re-encryption,which needs large amount of calculation and doesn’t apply to mas-sive data.To solve the problem,an efficient and immediate CP-ABE scheme was proposed to support user and attribute lev-els revocation.The scheme was based on the classic LSSS access structure,introducing RSA key management mechanism and attribute authentication.By means of a semi-trusted third party,the user could be authenticated before decryption.Com-pared with the existing revocation schemes,The proposed scheme didn’t need the user to update the key or re-encrypt the ciphertext.The semi-trusted third party wasn’t required to update the RSA attribute authentication key.The scheme greatly reduced the amount of computation and traffic caused by revocation,while ensuring anti-collusion attacks and forward and backward security.Finally,the security analysis and experimental simulation show that the scheme has higher revocation ef-ficiency.…”
Get full text

Research of the Operation Characteristic of New Type CVT System Used in Heavy Duty Drilling Automation Platform by Zhang Juan, Fan Minglong

“…In order to solve the problems of difficult arrangement,high production cost of drilling automation platform transmission system in the heavy duty condition,a new CVT system of drilling automation platform is introduced by analyzing the new type layout scheme of CVT structure,working principle and key performance indicators,and the influence of the differential mechanism transmission ratio of the new CVT system on the torque distribution ratio,output and input torque ratio of the new system and the influence of the reducing mechanism transmission ratio on the torque distribution ratio of the new system are calculated. Finally,the feasibility of new type CVT system of heavy duty drilling automation platform is validated by the test method. …”
Get full text

A Computable Measure of Algorithmic Probability by Finite Approximations with an Application to Integer Sequences by Fernando Soler-Toscano, Hector Zenil

“…We study formal properties of a Levin-inspired measure m calculated from the output distribution of small Turing machines. …”
Get full text

Automated Techniques for the Interpretation of Fetal Abnormalities: A Review by Vidhi Rawat, Alok Jain, Vibhakar Shrimali

“…Ultrasound medical images can easily identify the fetus using segmentation techniques and calculate fetal parameters. It can timely find the fetal abnormality so that necessary action can be taken by the pregnant woman. …”
Get full text

Design and Research of Multifunctional Lightweight Robots in Complex Terrain by Li Yinhe, Tian Yafeng

“…Combined with its design model, the maximum stride length of its movement, the maximum tilt angle, lifting range and other performance parameters are calculated and analyzed, and the stress and strain simulation is carried out. …”
Get full text

Research on Dynamic Characteristics of Robot Joint System Under Impact Load by Shuai Mo, Xu Li, Zhenning Yang, Changpeng Zhou, Guojian Cen, Yunsheng Huang

“…The influence of the natural frequency， and quality parameters of the system on the natural frequency of the system and the distribution law of modal energy is calculated and the torsional vibration characteristics of the gear system under impact load are analyzed. …”
Get full text

RESEARCH ON MECHANICAL CHARACTERISTICS OF NEW MOBILE ROLLER BRACKET CONVEYOR by ZHANG DongSheng, HE JinLong, NI Xue

“…On the basis of dynamic simulation,static simulation analysis of the conveyor under different working conditions was carried out by using finite element software Ansys to obtain the maximum stress and strain,and the safety factor of each component was calculated to verify the structural rationality. The dynamic response analysis of the reversing frame and the separation frame is carried out by using the New mark integration method in ANSYS workbench,and the displacement and acceleration transient values are obtained. …”
Get full text

Design and Dynamic Analysis of the Leveling System for Automatic Inspection Robots in Power Tunnels by Xu Shiyang, Wu Binghui, Ji Dongmei, Zhou Jiajun

“…Then, the dynamic analysis and calculation of the 3-RPS leveling mechanism are carried out to construct its dynamic model. …”
Get full text

Wideband DBF phased array antenna on LEO satellite by LIANG Guang1, GONG Wen-bin1, LIU Hui-jie1, YU Jin-pei1

“…Generalized DFT filter bank,multiplex DBF computer and RF calibration in close-loop mode were adopted to design the DBF network,which can reduce the calculation by 95.5% and save the multiplier resource up to 80%. …”
Get full text

Analysis of Sliding Characteristic of Traction Drive Reducer for Automotive In-wheel Motor by Shu Hongyu, Yao Zejie

“…Then,a mathematical model and an analysis method are proposed to accurately calculate the sliding characteristics combined with the elastohydrodynamic lubrication（ EHL） theory. …”
Get full text

Size Optimization Design of 3T1R Parallel Mechanism based on Workspace by Liu Zhenkun, Luo Yufeng, Shi Zhixin, Xia Yongqiang, Xie Dongfu

“…The algorithm has fewer calculation steps and fast solution speed,which provides a theoretical basis for the practical application of such parallel mechanism.…”
Get full text

A genetic algorithm based method of optimizing dispersion matrix for RDSM system by Peng ZHANG, Xiaoping JIN, Dongxiao CHEN

“…Rectangular differential spatial modulation (RDSM) is a multi-antenna incoherent modulation technology with high spectral efficiency, low power consumption, and zero-overhead for channel estimation.RDSM is especially suitable for 6G communication systems, such as fast-moving Internet of vehicles, Internet of things, cellular networks, etc.However, the construction of the sparse rectangular unitary space-time dispersion matrix (DM) at transmitter is a problem.The proposed Genetic algorithm (GA) will result in less computational complexity than the currently used random research.The fitness of GA was calculated by the rank and determinant criterion (RDC) method to avoid discussions in differential system.Due to characteristics of constellation symbols of RDSM, the proposed method reduced the computational complexity during each single iteration in GA.The simulation results show that the optimized DMS can significantly improve the bit error rate (BER) performance of the RDSM system.Compared with random search, the low-complexity GA effectively improves the DMS optimization efficiency of RDSM.The computational complexity required for optimizing DMS is about 0.1% of random search optimization method.…”
Get full text

Method of dynamic random network coding in DTN environment by Guang-hong DENG, Wan-hua CAO, Jian ZHANG, Li FENG, Xiong CHENG

“…Based on the Markov channel model, it first computed the transmit speeds of every network channel according to the receive data states of nodes, and then constructed the network flow graphic with channel capacities at the source node, calculated and forecasted the current network multicast capacity, after that, the random network coding scenario was extended and tailored according to the multicast capacity to transmit data packages under DTN environment. …”
Get full text

Design and Meshing Analysis of 3-DOF Spherical Gears and Ring Racks by Liang Yong, Gu Peng, Gao Jianjun, Zhang Litong, Wang Baichao

“…Finally, the kinematics simulation of the ring rack and the meshing efficiency of each layer of the ring rack were calculated, which verified that the structure can transmit power stably. …”
Get full text

Elastic and nonlinear crack tip solutions comparison with respect to failure probability by Valery Shlyannikov, Andrey Tumanov, Natalia Boychenko

“…The elastic SIF were experimentally obtained for studied materials and specimen geometries whereas the plastic SIFs were numerically calculated for the same material properties, specimen configurations and loading conditions according to classical J2 and strain gradient plasticity theories. …”
Get full text

SIMULATION AND ANALYSIS OF THE BUCKLING BEHAVIOR OF A STIFF FILM/COMPLIANT SUBSTRATE COMPOSITE UNDER IN-PLANE COMPRESSION by NIU HongWei, ZHANG Shuai, WEN Min

“…The buckling parameters under uniaxial and biaxial in-plane compression were calculated respectively utilizing an author compiled program. …”
Get full text

Regional heat and social attribute aware participant selection mechanis in mobile crowd sensing by Luoyong XIANG, Wen CHEN, Luyang ZHANG

“…Aiming at the problem of tasks that are low reliability acquired by platform and difficult to accomplish on time in user sparse area.A participant selection mechanism that combines regional heat and social attribute aware was proposed.Firstly,considering the influence of different regional heat on task completion,the regional heat was evaluated according to the number of active users,the average residence time of users and the completion of historical task.Secondly,in order to analyze the impact of user social attributes on task completion,the user willingness,reputation and activity were calculated by combining the status information of users and the historical task record of users.Finally,by taking the above factors into account,two different mechanisms of participant selection for social attribute perception were designed for high and low heat areas to maximize quality and number oftask completionrespectively.The results show that the proposed mechanism can significantly improve the overall data quality,and can also perform sensing tasks in sparse areas on time.Meanwhile,compared with SUR and GGA-I,the failure rate is reduced by 66.7% and 50.6% respectively.…”
Get full text

Anonymous security authentication scheme using elliptic curve cryptography and hash function in mobile network by Yuehui CHEN, Miao HUANG

“…In order to prevent personal data from being lacked and improve the existing mobile network roaming anonymous authentication scheme,anonymous security authentication scheme using elliptic curve cryptography and hash functions in mobile network was proposed.With elliptic curve cryptography and hash functions,random numbers were used to replace public key encryption and time stamp.Firstly,before using the roaming services of a foreign agent（FA）,hash function was calculated.A host agent（HA）was used by mobile user to register.Then,authentication and session key were set up with elliptic curve encryption.If HA is always in FA,MU can update the session key with FA.Finally,through a common channel,MU could utilize HA to change their passwords.The analysis of the performance and safety shows that,compared with other similar programs,the proposed scheme has significantly improved efficiency and safety.And the virtual computing time is only 2.000 85 seconds,which sharply reduces the cost of computing.…”
Get full text