bluuebunny/crossref_metadata_2025 huggingface dataset:
Deep Convolutional Neural Network for Pedestrian Detection with Multi-Levels Features Fusion
Authors: Li Danhua , Di Xiaofeng , Qu Xuan , Zhao Yunfei , Kong Honggang
Published: November 2018

Pedestrian detection aims to localize and recognize every pedestrian instance in an image with a bounding box. The current state-of-the-art method is Faster RCNN, which is such a network that uses a region proposal network (RPN) to generate high quality region proposals, while Fast RCNN is used to classifiers extract features into corresponding categories. The contribution of this paper is integrated low-level features and high-level features into a Faster RCNN-based pedestrian detection framework, which efficiently increase the capacity of the feature. Through our experiments, we comprehensively evaluate our framework, on the Caltech pedestrian detection benchmark and our methods achieve state-of-the-art accuracy and present a competitive result on Caltech dataset.
Finite Element Simulation for Dynamic Performance of a Dummy’s Head in Helicopter Anti-prang Tests
Authors: Lei Jingfa , Xuan Yan , Liu Tao , Zhang Miao , Sun Hong
Published: November 2018

The dynamic performance of a dummy’s head plays a important role in the research of helicopter anti-prang testing. In this paper, we firstly construct the finite element model for a dummy’s head based on the parameter features of 50th percentile Chinese pilot. Then, the dynamic performance of the head model is simulated according to the calibration rules. After comparing the simulation results with the reference index of the dummy head’s dynamic performances, we find that the FE model has good anthropopathic integrality, and the simulation method used to analyze the dynamic performance of the dummy’s head is correct and validated. This paper has practical guiding significance in the study of helicopter anti-prang testing and other dummy parts, which also provide the reference value for the improvement of dummy structure.
Design Of Video Bitrate Analyzer Based On Swift
Authors: Zhong Xiuyu , Luo Zhongyi
Published: November 2018

Network video is very popular, users often upload video, Video site allows specific coded video to maintain the original specification at a certain peak rate, and then to add lower-level specifications to the code. At present, many analysis tools can only get the maximum rate of the whole video, and cannot get the rate map, nor support the new video format. This design proposes using the Swift language to display the video bitrate analysis data in different forms, FFmpeg/ffprobe applications is called to analyze video stream. The experimental results show that the design can get the information of all frames of the video to depict the column chart, and can display the corresponding time point of the frame, so that users can modify the area exceeding the rate limit, so as to achieve the goal of no forced transcoding. In addition, this design supports HEVC format video.
Sigmoid Function based Modelling and Route Tracking of Obstacle avoidance for Ship in Restricted Water
Authors: Zhao Yue , Wang Renqiang , Sun Jianming , Liu Changhua , Li Jingdong , Chen Dawei
Published: November 2018

In order to solve the problem of obstacle avoidance of ship in restricted waters, a type of path planning method for obstacle avoidance based on sigmoid function was designed. Firstly, with the concept of path planning, sigmoid function was used to construct the trajectory of ship movement for obstacle avoidance on the basis of analyzing the process of ship obstacle avoidance and the geometric features of sigmoid function. Then, the route tracking in real time was achieved by ship motion control system based on active disturbance rejection control. The simulation shows that ship can ensure avoid obstacle and that the route built based on sigmoid function in confined waters is effective.
Linear Reconstruction Methods for Large Thick Aperture Imaging
Authors: Yao Zhiming , Duan Baojun , Yan Weipeng , Song Yan , Han Changcai , Ma Jiming , Song Guzhou
Published: November 2018

Large thick aperture imaging method is proposed to measure the radiation intensity distribution of radiation source whose size is several centimetres. The new method contains two steps which are coded imaging and image reconstruction. Geant4 is used to simulate the coded imaging process. Wiener filter, Lucy-Richardson, Regularized filter, blind deconvolution and CT reconstruction method are realized using Matlab software. Wiener filter and Regularized filter produce artifacts. CT reconstruction method can’t reveal the right size of60Co-γ source because of the overlapping of knife edge images. Both L-R and blind deconvolution are effective. If the aperture is moved 0 mm, 2 mm, 4 mm, 6 mm along x-axis, the reconstruction result using L-R method has a larger correlation coefficient with source image. However, L-R method gets bad result if the aperture rotates more than 1.4°. Under this condition, blind deconvolution is the better choice.
Study on Flipped Classroom Teaching Mode Based on Learning Space in WorldUC
Authors: Ye Lijuan , Zhong Jiaming
Published: November 2018

The learning space in worldUC is an effective way to construct a web-based, digital, personal, and life-long educational system, as well as to bring forth new educational teaching modes. Therefore, this paper introduces the construction and function of learning space in worldUC, and analyzes the connotation, targets, as well as meaning of flipped classroom. Meanwhile, it puts forward the implementation, basic principles, and strategies for flipped classroom, and proposes suggestions for flipped classroom, to provide references for flipped classroom.
An Approach to Source Code Plagiarism Detection Based on Abstract Implementation Structure Diagram
Authors: Guo Shuang , Liu JianBin
Published: November 2018

Source-code plagiarism detection in programming, concerns the identification of source-code files that contain similar and/or identical source-code fragments. Based on the analysis of the characteristics and defects of the existing program code similarity detection system, a method of source code similarity detection based on Abstract Implementation Structure Diagram (AISD) is proposed. The source code modelling and format into an abstract implementation structure diagram, and forming structural feature strings and variable reference relationship sequences by extracting structural features and variable position features. We calculate the overall similarity by calculating structural similarity and variable similarity. The results demonstrate that the performance of the proposed AISD-based approach overcomes other approaches on the same source code datasets, and reveals promising results as an efficient and reliable approach to source-code plagiarism detection.
Study on forming process and spring back control of high strength sheet based on Dynaform
Authors: Liu cunping
Published: November 2018

The drawing process of a high strength steel part without blank holder force was numerically simulated based on Dynaform. In present investigation, the drawing velocity and velocity profile motion of punch was studied by simulating the drawing operation of high strength steel part. The results show that restricting drawing velocity and controlling velocity profile motion of punch could all reduce the spring back. The measure of restricting drawing velocity could reduce non-pressure forming spring back about 31% and Trapezoidal motion mode of punch is the most beneficial to reduce spring back.
Research on Buffering Performance of Several Polymer Materials Based on Drop-weight Test
Authors: Lei Jingfa , Chen Zhiqiang , Zhang Miao , Liu Tao , Sun Hong
Published: November 2018

Polymer materials are widely used in vibration damping and buffering, and different materials and processing techniques would affect their buffering performance. In this study, the buffering performance of four kinds of specimens made of non-foamed polyurethane, foamed polyurethane, silicone rubber and PVC paste resin were examined by drop-weight tests. According to the drop-weight experimental principle and corresponding numerical simulation, the peak acceleration of the falling hammer could be used as the key index of buffering performance. The results show that the buffering performance of the non-foamed polyurethane and silicone rubber samples are relatively worse, while the foaming polyurethane and PVC paste resin samples have similar buffering performance.
Optimization of Machining Parameters of SiC Single Crystal Cut by Diamond Wire Saw
Authors: Li Lun , Yang Shaodong , Li Jishun
Published: November 2018

For the process of optimizing the process parameters in the process of cutting the hard and brittle materials such as single-crystal SiC by diamond wire saw, the process parameters such as wire saw speed, workpiece feed speed and workpiece rotation speed are the design variables, and the sawing force and surface roughness are the processing targets by orthogonal experimental design. The grey system theory is introduced to optimize the multi-objective cutting process. According to the experimental data, the grey correlation resolution coefficient is determined. The significant relationship between the processing parameters and the target characteristics is analyzed. The optimal combination of process parameters under multi-target conditions is obtained, namely the workpiece feed rate is 0.025mm/min, the wire saw speed is 1.6m/s, and the workpiece rotating speed is 16r/min.
Distribution characteristics of seepage field and prediction of water inflow before and after tunnel construction
Authors: Cao Ruilang , Pang Shijie , Huang Chang , Chen Chen
Published: November 2018

In the construction of a deep tunnel with rich water and soft rock, accurate evaluations of the distribution characteristics of seepage field and water inflow are important bases for predicting the stability of tunnel surrounding rock and the disturbance state of groundwater environment. This paper used the Flac3D finite difference software seepage module, based on field geological borehole, measured seepage parameters and groundwater level. A three-dimensional numerical model of geological seepage in engineering area was established. The distribution characteristics of groundwater seepage field, the variation law of seepage field before and after tunnel excavation, and the water inflow during construction period were studied. As the tunnel was excavated, the excavated surface became a drainage channel, the isoline of groundwater pressure was changed into parallel non-parallel curve set by the parallel line of the initial seepage field. The nearer the tunnel centre was, the more obvious the variation tendency of groundwater pressure was. Grouting measures were very effective for tunnel water gushing, which not only reduced water inflow, but also effectively reduced the external water pressure of lining. It was infeasible to plug water when blocking the water without grouting and only adjusting the permeability of the lining.
An Improved Particle Swarm Optimization with Gaussian Disturbance
Authors: Wen Changjun , Liu Changlian , Zhang Heng , Wang Hongliang
Published: November 2018

The particle swarm optimization (PSO) is a widely used tool for solving optimization problems in the field of engineering technology. However, PSO is likely to fall into local optimum, which has the disadvantages of slow convergence speed and low convergence precision. In view of the above shortcomings, a particle swarm optimization with Gaussian disturbance is proposed. With introducing the Gaussian disturbance in the self-cognition part and social cognition part of the algorithm, this method can improve the convergence speed and precision of the algorithm, which can also improve the ability of the algorithm to escape the local optimal solution. The algorithm is simulated by Griewank function after the several evolutionary modes of GDPSO algorithm are analyzed. The experimental results show that the convergence speed and the optimization precision of the GDPSO is better than that of PSO.
Scale Adaptive Kernel Correlation Filter Tracking Algorithm Combined with Learning Rate Adjustment
Authors: Wu Di , Peng Li
Published: November 2018

Aiming at the problem that the traditional correlation filter tracking algorithm is prone to tracking failure under the target’s scale change and occlusion environment, we propose a scale-adaptive Kernel Correlation Filter (KCF) target tracking algorithm combined with the learning rate adjustment. Firstly, we use the KCF to obtain the initial position of the target, and then adopt a low-complexity scale estimation scheme to get the target's scale, which improves the ability of the proposed algorithm to adapt to the change of the target's scale, and the tracking speed is also ensured. Finally, we use the average difference between two adjacent images to analyze the change of the image, and adjust the learning rate of the target model in segments according to the average difference to solve the tracking failure problem when the target is severely obstructed. Compared the proposed algorithm with other five classic target tracking algorithms, the experimental results show that the proposed algorithm is well adapted to the complex environment such as target’s scale change, severe occlusion and background interference. At the same time, it has a real-time tracking speed of 231 frame/s.
Parameter Optimization Of CPG And Its Application In Robot
Authors: Lu Qiang , Zhang Zhaochen , Li Wenfeng
Published: November 2018

The central pattern generator (CPG) has been identified in the spinal cords as responsible for locomotion movements. It is difficult to select the appropriate values of parameters in CPG model. In this paper, the Matsuoka oscillator is selected as the rhythm-generation model and the bat algorithm is chosen to search the parameters of CPG model. The paper shows the details of the parameters optimization and the diagram of the convergence performance. In the paper, the CPG includes the main rhythm-generation neuron and the minor pattern-formation neuron, and Rowat's neural model is chosen as the pattern-formation neuron. Then the CPG model is applied to the three-link biped robot and the result shows that the method of parameter optimization is effective.
Thermal seepage measurement in rock and soil
Authors: Zhang Chao , Li Qing
Published: November 2018

In the measurement of seepage in rock and soil, the osmotic pressure meter is mainly used to measure the infiltration water pressure inside rock and soil, and then the seepage monitoring is performed. The measurement is scalar, and there is a poor dynamic response, small range, nonDirect measurement and other defects are difficult to meet the needs of monitoring and development of seepage in rock and soil; in view of this, a remote online flow meter based on the principle of thermal diffusion is designed; it consists of power module, temperature detection module, constant power heating module, and display module. Three-wire platinum resistance constant current source temperature measurement circuit detects the temperature difference between the two ends of the influent water, the test results are returned to the display to the stm32 and passed through RS485 to the host for data analysis; experimental results show that the flow meter can be implemented on-line monitoring The seepage in rock and soil can effectively detect the velocity of seepage in rock and soil, with a resolution of 0.05ml/s. Thermal percolation meter has good sensitivity, accuracy and repeatability, and is suitable for the seepage measurement of most types of rock and soil.
Countermeasure for Interrupted-sampling Repeater Jamming based on Fractional Fourier Transformation
Authors: Liu Ming , Tao Shu , Chen Qingrong
Published: November 2018

Today, the interrupted-sampling repeater jamming (ISRJ) has posed a serious threat to LFM radars. In this paper, a countermeasure to suppressing ISRJ based on fractional Fourier transformation (FrFT) is presented. The echo signals, mixed with ISRJ, will be processed in FrFT of specific order, and then a narrow band filter based on parameters of FrFT is designed to extract the target signals and suppress interference signal, so as to realize the target detection. The three kinds of models of ISRJ (ISDRJ, ISRRJ, ISCRJ) are introduced; the anti-jamming principles are analyzed and simulated. The simulation results show that, the algorithm has low complexity and takes short operation time, and it is effective in low SNR or high JSR condition.
Prediction of Cable Junction Temperature in Power Transmission System based on BP Neural Network optimized by Genetic Algorithm
Authors: Gao Xi , Zhang Hai , Li Shixin , Min Chunhua
Published: November 2018

Two forward neural networks were established in this study. Training and learning of reflection factor data and prediction results were conducted respectively then the weights and thresholds of the two networks are optimized by genetic algorithm, finally the set of target values can still be predicted without reflection factor data. In order to predict the temperature of the conductor in the cable joint of a power transmission system, the genetic algorithm is used to optimize the BP neural network to establish an effective prediction model based on the analysis of the related reflection factors. This model not only has the strong learning ability of BP neural network, but also combines the excellent global searching ability of genetic algorithm. The innovation of this research is that the network 1 is used to train the reflective factor data to get the corresponding time point temperature value, and then the reflective factor data of three consecutive time points are trained by the network 2 to get the fourth time point temperature value. The whole process of solving the temperature value of the fourth time point does not need the reflective factor data of the time point.
A Multi-objective Particle Swarm Optimization Based on P System Theory
Authors: Chen Taowei , Yu Yiming , Zhao Kun
Published: November 2018

Particle swarm optimization(PSO) algorithm has been widely applied in solving multi-objective optimization problems(MOPs) since it was proposed. However, PSO algorithms updated the velocity of each particle using a single search strategy, which may be difficult to obtain approximate Pareto front for complex MOPs. In this paper, inspired by the theory of P system, a multi-objective particle swarm optimization (PSO) algorithm based on the framework of membrane system(PMOPSO) is proposed to solve MOPs. According to the hierarchical structure, objects and rules of P system, the PSO approach is used in elementary membranes to execute multiple search strategy. And non-dominated sorting and crowding distance is used in skin membrane for improving speed of convergence and maintaining population diversity by evolutionary rules. Compared with other multi-objective optimization algorithm including MOPSO, dMOPSO, SMPSO, MMOPSO, MOEA/D, SPEA2, PESA2, NSGAII on a benchmark series function, the experimental results indicate that the proposed algorithm is not only feasible and effective but also have a better convergence to true Pareto front.
Doublel-robot coordination workspace Analysis based on Matlab
Authors: Wang Wei , Xu Yong
Published: November 2018

Aiming at the requirements of dual robot collaborative operation, a dual robot cooperation system model is established in SolidWorks2012 software to study the dual robot cooperation space. The D-H parameters are established, and the kinematics positive solution equation is obtained. The dual robot cooperative kinematics model is given. Based on the Monte Carlo method, the workspace of the dual robot is solved. The extreme value theory method is used to analyze and calculate, so as to extract the precise boundary contour of the common area of the dual robot workspace, and the collaborative space boundary surface and limit position of the dual robot are determined. The optimal coordinated working space of the dual robot end effector is obtained, which lays a theoretical foundation for the coordinated trajectory planning of the dual robot.
Research on Anti-saturation Feedback Control Method for UAV Avionics System
Authors: Zhang Xiao-Jun
Published: November 2018

UAV avionics system is prone to saturation distortion under unsteady conditions, so anti-saturation control is needed. A control method of UAV avionics system based on anti-saturation feedback compensation is proposed. The anti-saturation control process of UAV avionics system is a multi-objective optimization process with multi-variables. The constrained parameter model of UAV avionics system control is constructed. Electromagnetic loss, torque, output power and other parameters are taken as constraint indexes, the original control information of UAV avionics system is treated with self-stabilization, the equivalent control circuit is designed, and the magnetic resonance transmission mode of avionics system is analyzed. An anti-saturation feedback tracking control method is used for steady-state control of the output voltage of the avionics system. The error compensation function is constructed to adjust the output adaptive parameters of the avionics system and the static anti-saturation compensator is constructed to compensate the power gain. The yaw error and the output steady-state error of the avionics system are reduced. The simulation results show that the proposed method has better output stability, lower output error, better real-time performance and better linear auto-disturbance rejection control performance.
Electric Air Conditioning Control Method of Electric Bus Based on Driving Conditions
Authors: Luo Yong , Li Li-fu , Tan Yan-ping
Published: November 2018

For reducing energy consumption of electric air conditioning (E-A/C) in electric bus, an E-A/C control method based on driving conditions (including the temperature of bus compartment, the number of passengers, the state of charge (SOC) of battery) is proposed. Firstly, the relationship between E-A/C cooling load and driving conditions is theoretically researched, then an E-A/C control method by dynamically adjusting compartment temperature is proposed. Secondly, an E-A/C model and a bus model are established and simulated in AVL Cruise and MATLAB, the results indicate that the proposed control method can reduce the energy consumption of E-A/C significantly, and effectively improve electric bus performance.
Research and Application of Electronic Invoice Based on Blockchain
Authors: Liu Xidong
Published: November 2018

Blockchain technology can effectively solve the problems of intermediaries' trust risk, reduce transaction costs and improve synergy efficiency in a multi-agent environment. This paper discusses the feasibility of applying blockchain technology to electronic invoices, and designs the overall structure of the electronic invoice blockchain. Moreover, in the paper, it is proposed to establish an electronic invoice alliance chain, and realize the research ideas of various transactions within the alliance through intelligent contracts.
A Novel Vector Control of Five-phase PMSM Based on Harmonic Current Closed Loop
Authors: Yu Fei , Zhou Yongchao
Published: November 2018

Multi-phase electric machines such as five-phase permanent magnet synchronous motor (PMSM) play an important role in the ships electrical propulsion because of the advantages of high performance and high reliability. The decoupled mathematic models of five-phase PMSM in dq coordinate frame are established, and the reason caused to high stator harmonic current in the multi-phase motor is analyzed based on the mathematic models. To suppress the harmonic current, a novel vector control (VC) method based on SVPWM and harmonic current closed loop control is proposed. Based on the proposed algorithm, a five-phase PMSM vector control system is established with MATLAB, the performance is simulated and analyzed. The results show that, the stator harmonic current is much little than that of the traditional control method.
Sparsity-Constrained NMF Algorithm Based on Evolution Strategy for Hyperspectral Unmixing
Authors: Ning ShangBin , Zuo FengChao
Published: November 2018

As a powerful and explainable blind separation tool, non-negative matrix factorization (NMF) is attracting increasing attention in Hyperspectral Unmixing(HU). By effectively utilizing the sparsity priori of data, sparsity-constrained NMF has become a representative method to improve the precision of unmixing. However, the optimization technique based on simple multiplicative update rules makes its unmixing results easy to fall into local minimum and lack of robustness. To solve these problems, this paper proposes a new hybrid algorithm for sparsity constrained NMF by intergrating evolutionary computing and multiplicative update rules (MURs). To find the superior solution in each iteration,the proposed algorithm effectively combines the MURs based on alternate optimization technique, the coefficient matrix selection strategy with sparsity measure, as well as the global optimization technique for basis matrix via the differential evolution algorithm .The effectiveness of the proposed method is demonstrated via the experimental results on real data and comparison with representative algorithms.
AUV path planning for environment changes over time
Authors: Li Jianping , Shi Yuliang
Published: November 2018

Path planning is an important research field in robotics, and it is also a key technology for realizing automatic navigation of aircraft. It is of great significance both in theory and in application. The task of planning trajectories for an aircraft has received considerable attention in the research literature. Most of the work assumes that the threat to the aircraft is static; less attention has been paid to the problem of the changing environment. However, the threat from the weather when the UAV is flying in the air is always changing. This paper introduces an improved BFS algorithm, which can find the best safe path when the threat is always changing.
Design of Multi-threshold Acceleration Switch Based on Matlab
Authors: Feng Jiacheng , Ma Jun , Gong ZaiYan , Kang Di , Wang Chao
Published: November 2018

Acceleration switch can trigger switches according to the variation of external acceleration without complex control system and circuit. With the excellent characteristics of integration of sensor and actuator, zero power consumption and high reliability, multi-threshold acceleration switch has great application value in the fields of vehicle safety, aerospace and industrial equipment. In order to reduce the complexity of the measurement system and improve the reliability, we realized the design of a multi-threshold and anti-overloading acceleration switch which can distinguish specific pulse width. Additionally, the magnetic elastic contact is designed to prevent the rebound phenomenon when switch is overloaded. Considering the coupling force of spring, magnetic elastic contact and magnetic, we built the dynamic model and analysed the influence of the acceleration threshold and the pulse width on the switch actuation. The numerical simulation shows that the proposed switch has accurate sensitivity of acceleration excitation with specific threshold and certain pulse width, and it also has the ability of anti-overload. Consequently, the proposed method provides a new method for designing acceleration switch.
Research of Space Positioning Method Based on Sound Field HBT Interference
Authors: Zou Jing , Nie Lei , Liu Mengran , Jiang Chuankai
Published: November 2018

Based on Hanbury Brown-Twiss (HBT) interference in the sound field, a space positioning method is presented to realize the long-distance and high-precision positioning of sound sources in media. Firstly, theoretical model of HBT interference positioning is established. Location of the sound source can be acquired by analyzing the correlation function of the output signals. Then, sound source localization under different signal-to-noise ratios (SNR) shows that by this method, the sound source can be accurately found with six sensors (two arrays) even the SNR is low to 0.04. Positioning experiment in air is carried out, and the experimental results show that the sound source can be accurately located at 42 meters, and the positioning error is low to 0.1 meters. Thus the validity and accuracy of the HBT interference space location principle is demonstrated. It provides new ideas for the research of long-range target location in sound propagation media (air, water, etc.).
Capacity Analysis of Distributed Antenna Systems with Beamforming
Authors: Ju Meiyan , Chen Chao , Li Yueheng , Tan Guoping
Published: November 2018

Distributed antenna systems (DASs) can reduce the access distance, increase system capacity and improve system performance compared with conventional centralized multiple antenna systems. In this paper, the system capacity of downlink DAS with beamforming is investigated. The mathematical expression of system capacity is derived over the composite channel including Rayleigh fading, shadowing and path loss. At the same time, the interference from other APs is also considered for the studied AP. Numerical methods including Gauss-Hermite integral and composite Simpson’s rule are used to compute the system capacity of DAS under diﬀerent MS distributions. Numerical results verify the precision of the mathematical analysis of system capacity by comparing Monte-Carlo simulation results. The results also show interference among APs shouldn’t be ignored when APs are close to each other or there are many APs.
Analysis and Simulation about a Simplified Model for Modulation and Demodulation of Ship-borne Single Channel Monopulse Radar
Authors: Zhang Xudong , Ji Haiyu
Published: November 2018

A simplified mathematical model for modulation and demodulation of a single channel monopulse (SCM) system is proposed, which is based on a ship-borne pulse radar S-band guided receiver. Using the proposed mathematical model, the modulation and demodulation of single-channel and multi-channel signals were simulated respectively, and the factors influencing the modulation and demodulation of the SCM system were analysed.
EPS Sensor Torsion Bar Design and Structure Analysis
Authors: Fang Shu-juan , Lv Qing-tao
Published: November 2018

Torsion bar design is very important on Electrical power steering(EPS) development. The mathematical model and structure for torsion bar are developed, and the torsion bar outer spline is cancelled based on the automotive parameters. This kind of structure leads to cost down and time saving on torsion bar manufacturing process. The 3D model and finite element on sub-EPS(torsion bar, input shaft, output shaft) are developed, and then do the contact nonlinear analysis based on interference between torsion bar and output shaft. The EPS structure and test reliability according to function test and durability test are verified and the test results are passed.
Parameter estimation in multi-antenna system based on iterative adaptive approach
Authors: Lei Lihua , Zhou Ju
Published: November 2018

As one of the main means for remote sensing and detecting, synthetic aperture radar is playing more important role in many fields such as country reconnaissance, ocean observation, environment disaster monitoring and military reconnaissance. The synthetic aperture radar system based on multi-antenna technology can achieve high resolution of still image and estimate the motion parameter. The echo model of target is set up for motion parameter estimation and the performance of system parameter estimation is given according to the moving target velocity estimation method based on iterative adaptive approach.
An analysis of mobility management for mobile sensor nodes in MWSN
Authors: Zhang Min , Liang Jun-Bin
Published: November 2018

Mobile wireless sensor networks (MWSN) are composed of a large number of mobile sensor nodes, which are used to collect data. MWSN have been widely applied in a variety of harsh environments, so mobile sensor nodes are often at risk of damage. How to manage mobile sensor nodes is an important issue. In this paper, we analyse different mobility management schemes proposed in some typical research literature and classify these schemes by using three features: the collaboration between mobile sensor nodes, routing and deployment in MWSN. We specify advantages and disadvantages of the proposed schemes, compare different key parameters of MSWN respectively, including energy efficiency, data delay, cost and lifetime, etc. Finally, we discuss existing problems of MWSN management and give some helpful suggestions in this area.
Improving Wavelet Threshold De-noising Applied on Parts Detection
Authors: Cheng Lizhou , Mao Jian , Wei Hongyuan
Published: November 2018

The traditional filtering methods such as median filter and mean filter always blurrs image features, resulting in poor noise reduction effect. Wavelet transform has unique adaptability due to its variable resolution, which can better implement wavelet denoising on the basis of image feature. Aiming at the shortcoming of traditional wavelet transform threshold denoising, based on the hard threshold and soft threshold function, this paper proposes improved adaptive thresholding function. By comparing and validating, this method obtains the smaller mean square error (MSE) and higher peak signal to noise ratio. Meanwhile, this method improves the quality of detection images, and reduces the impact on images brought by noise from external enviroment and internal system. So, this can be applied to image noise reduction of the detection system.
La biopsie liquide
Authors: Thierry Alain R. , Tanos Rita
Published: November 2018

La biopsie liquide est apparue comme une voie prometteuse pour le dépistage du cancer. En effet, plusieurs biomarqueurs comme les ADN circulants, les cellules tumorales circulantes, les micro-ARN circulants etc. se sont révélés prometteurs pour le théragnostic ou le suivi du patient. La détection précoce peut aider à réduire la mortalité associée au cancer et augmenter la survie globale des patients. La plupart des types de cancer manquent de biomarqueurs spécifiques et le développement de techniques de dépistage efficaces appliquées en clinique a été limité malgré des efforts intenses dans ce domaine. La nature non invasive de la biopsie liquide lui donne un avantage vis-à-vis d’autres méthodes, notamment pour le développement de tests de dépistage du cancer. Les différentes études fondées sur l’analyse de la biopsie liquide dans le but de développer des tests de dépistage et de détection précoce du cancer sont présentées dans cette revue. Bien qu’actuellement aucun test développé à partir de la biopsie liquide s’avère à la fois assez spécifique et sensible pour être utilisé comme test universel de dépistage, le potentiel de cette nouvelle approche apparaît de plus en plus crédible, eu égard aux récents développements de méthodes sophistiquées, notamment multiparamétriques.
C.S. Peirce
Authors: Duvauferrier Régis , Mejdoubi Mehdi , Bertaud Valerie
Published: November 2018

Modéliser les connaissances et le raisonnement médical peut être un projet épistémologique à l’heure où la médecine atteint un statut scientifique. Par ses travaux sur la sémiotique, le raisonnement abductif et le pragmatisme, C.S. Peirce (1839-1914) propose une série de solutions originales. Celles-ci peuvent rendre compte d’une grande partie de l’activité médicale dans divers domaines, comme l’évaluation des étudiants, les bases de connaissances et les systèmes experts, les langages de descriptions formelles (ontologies), la médecine fondée sur les preuves. Par ce texte, nous souhaitons présenter aux acteurs de la biomédecine cette pensée complexe mais éclairante sur une profession qui utilise désormais toutes les ressources les plus modernes de l’ingénierie des connaissances.
Outcome and Associated Findings in Individuals with Pre- and Postnatal Diagnosis of Tetralogy of Fallot (TOF) and Prediction of Early Postnatal Intervention
Authors: Wolter Aline , Gebert Marie , Enzensberger Christian , Kawecki Andrea , Stessig Rüdiger , Degenhardt Jan , Ritgen Jochen , Thul Josef , Khalil Markus , Herrmann Johannes , Axt-Fliedner Roland
Published: November 2018

Purpose The aim of our retrospective evaluation was to compare the outcome of patients with prenatal and postnatal diagnosis of Tetralogy of Fallot (TOF) and to analyze prenatal echocardiographic parameters predicting intervention within 30 days postnatal.

Materials and Methods We evaluated 142 patients in our pediatric heart center and prenatal diagnosis center and prenatal practice Praenatal plus in Cologne between 01/08–06/16.

Results Within the prenatal diagnosis group, 6/74 fetuses (8.1 %) had TOF with pulmonary atresia (TOF-PA), and 6 (8.1 %) had absent pulmonary valve syndrome (TOF-APVS). 14 (18.9 %) had an abnormal karyotype including 9/14 (64.3 %) with microdeletion 22q11.2. 25 (33.8 %) had extracardiac malformation. 4 (5.4 %) had agenesis of ductus arteriosus (DA), 22 (29.7 %) had right aortic arch (RAA) and 9 (12.2 %) had major aortopulmonary collateral arteries (MAPCAs). Within the postnatal diagnosis group, no patient had TOF-PA, 4/68 (5.9 %) had TOF-APVS. 12 (17.6 %) had extracardiac malformations, 9 (13.2 %) had an abnormal karyotype including 2/9 with microdeletion 22q11.2. 10 (14.7 %) had RAA, 9 (13.2 %) had MAPCAs. There were no cases with agenesis of DA. Increasing z-score values of the left/right pulmonary artery (LPA/RPA) prenatally were associated with a lower probability for early postnatal intervention (RPA: p = 0.017; LPA: p = 0.013). Within the prenatal diagnosis group, 12 of 41 (29.3 %) live-born patients with follow-up and intention to treat needed early intervention versus 7 (10.3 %) in the postnatal diagnosis group (p = 0.02). Within the postnatal diagnosis group, there were no deaths, while 2 (4.9 %) post-intervention deaths occurred in the prenatal diagnosis group.

Conclusion There are no significant differences concerning post-intervention survival in the prenatal diagnosis group versus the postnatal diagnosis group. Complex cases may be underrepresented in the postnatal diagnosis group. Smaller RPA/LPA values prenatally seem to be associated with early postnatal intervention.
Anti-Inflammatory Activity of Lobaric Acid via Suppressing NF-κB/MAPK Pathways or NLRP3 Inflammasome Activation
Authors: Lee Hee-Weon , Kim JinWook , Yim Joung-Han , Lee Hong-Kum , Pyo Suhkneung
Published: November 2018

Lobaric acid (LA) is a constituent of the lichen Stereocaulon alpinum. LA has multiple biological activities, including antibacterial and antioxidant ones. The purpose of this study was to investigate the effect of LA and its mechanism on lipopolysaccharide (LPS)-induced inflammatory responses in macrophages. Macrophages were pretreated with different concentrations of LA (0.2 – 20 µM), followed by LPS stimulation. LA treatment of LPS stimulated macrophages decreased their nitric oxide production and the expression of cyclooxygenase-2 and prostaglandin E2. LA also significantly reduced the production of tumor necrosis factor-α and interleukin (IL)-6 by inhibiting the activation of mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-κB). Additionally, LA inhibited the production of IL-1β and IL-18, as well as caspase-1 maturation, by inhibition of NLRP3 inflammasome activation in LPS/ATP-stimulated cells. These results strongly suggest that LA could inhibit inflammation by downregulating NF-κB/MAPK pathways and NLRP3 inflammasome activation in activated macrophages. These results reveal a new therapeutic approach to modulate inflammatory diseases linked to deregulated inflammasome activities.
Six-Month Performance of a 3-Dimensional Annuloplasty Ring for Repair of Functional Tricuspid Regurgitation
Authors: Guenzinger Ralf , Lange Ruediger S. , Rieß Friedrich-Christian , Hanke Thorsten , Bischoff Nicolas , Obadia Jean-Francois , Sahar Gideon , Bitran Dani , Roberts Harold , Li Shuzhen , Bolling Steven F.
Published: November 2018

Background Functional tricuspid regurgitation (FTR) secondary to left-sided heart disease may lead to poor quality of life and reduced long-term survival. This study evaluated clinical and functional outcomes of patients undergoing tricuspid valve (TV) repair using a rigid three-dimensional ring (Contour 3D, Medtronic) concomitant with another procedure.

Methods From September 2011 to July 2015, 112 patients (mean age 70.9 ± 9.0 years) were enrolled at 10 centers in Europe, Israel, and the United States. Inclusion criteria were FTR ≥ moderate and/or tricuspid annular diameter (TAD) ≥ 40 mm. Echocardiography was planned before surgery and at discharge with echocardiographic and clinical follow-ups performed 6 months postoperatively.

Results Three fourths (74.4%) of patients had higher than moderate TR. Mean TAD was 41.0 ± 7.3 mm; 61.7% of patients were in the New York Heart Association (NYHA) class III/IV. The most common concomitant procedure was mitral valve repair (57 patients, 53.3%). The 30-day mortality rate was 0.9% (n = 1). The mean EuroSCORE II was 8.9 ± 8.4% (median: 5.9%; interquartile range: 3.5–11.5%). The observed to expected ratio (O/E) based on the median was 0.1. Six deaths occurred during follow-up (three cardiac related). Mean implanted ring size was 30.3 ± 2.7. At 6 months, 94.4% of patients showed ≤ mild TR, and 92.0% were in NYHA class I/II (p < 0.001 vs baseline for both). Mean pressure gradient across the TV was 2.0 ± 1.1 mm Hg; leaflet coaptation length was 7.5 ± 3.3 mm.

Conclusion The Contour 3D annuloplasty ring used for treatment of FTR substantially reduced TR for up to 6 postoperative months with low mean pressure gradients across the TV and significant improvement in NYHA class.

Registration www.ClinicalTrials.gov, NCT01532921.
α1-Antichymotrypsin Present in Therapeutic C1-Inhibitor Products Competes with Selectin–Sialyl LewisX Interaction
Authors: Engel Ruchira , Delvasto-Nuñez Laura , Roem Dorina , van Mierlo Gerard , Holst Stephanie , Hipgrave Ederveen Agnes , van Buul Jaap , Wuhrer Manfred , Wouters Diana , Zeerleder Sacha
Published: November 2018

Background C1-inhibitor (C1-inh) therapeutics can reduce neutrophil activity in various inflammatory conditions. This ‘novel’ anti-inflammatory effect of C1-inh is attributed to the tetrasaccharide sialyl LewisX (SLeX) present on its N-glycans. Via SLeX, C1-inh is suggested to interact with selectins on inflamed endothelium and prevent neutrophil rolling. However, C1-inh products contain plasma glycoprotein α1-antichymotrypsin (ACT) as a co-purified protein impurity.

Objective This article investigates the contribution of ACT to the effects observed with C1-inh.

Materials and Methods We have separated C1-inh and ACT from a therapeutic C1-inh preparation and investigated the influence of these proteins on SLeX–selectin interactions in a specific in vitro model, which makes use of rolling of SLeX-coated beads on immobilized E-selectin.

Results We find that ACT and not C1-inh, shows a clear sialic acid-dependent interference in SLeX–selectin interactions, at concentrations present in C1-inh therapeutics. Furthermore, we do not find any evidence of SLeX on C1-inh using either Western blotting with anti-SLeX antibodies (CSLEX1 and KM93) or by mass spectrometric analysis of N-glycans. C1-inh reacts weakly to antibody HECA-452, which detects a broad range of selectin ligands, but ACT gives a much stronger signal, suggesting the presence of a selectin ligand on ACT.

Conclusion The ‘novel’ anti-inflammatory effects of C1-inh are unlikely due to SLeX on C1-inh and can in fact be due to SLeX-like glycans on ACT, present in C1-inh products. In view of our results, it is important to assess the role of ACT in vivo and revisit past studies performed with commercial C1-inh.
Stroke Severity in Patients on Non-Vitamin K Antagonist Oral Anticoagulants with a Standard or Insufficient Dose
Authors: Jung Yo , Choi Hye-Yeon , Lee Kyung-Yul , Cheon Kyeongyeol , Han Sang , Park Joong , Cho Han-Jin , Park Hyung , Nam Hyo , Heo Ji , Lee Hye , Kim Young
Published: November 2018

Background The stroke severity or functional outcomes could differ because the efficacy of non-vitamin K antagonist oral anticoagulants (NOACs) could be different according to the dose. We investigated whether there was any difference in the stroke outcomes in patients with non-valvular atrial fibrillation (NVAF) by their prior medication status, including standard-dosed versus under-dosed NOACs.

Materials and Methods We enrolled 858 patients with acute ischaemic stroke with chronic NVAF admitted at six hospitals in Korea. We categorized their prior medication status as follows: (1) no anti-thrombotics (n = 219), (2) only anti-platelet (n = 347), (3) warfarin with a sub-therapeutic intensity (n = 185), (4) warfarin with a therapeutic intensity (n = 37), (5) under-dosed NOAC (n = 27) and (6) standard-dosed NOAC (n = 43). We compared the initial stroke severity between groups.

Results Among the 858 patients, the patients on standard-dosed NOACs had the lowest initial National Institute of Health Stroke Scale (NIHSS) score, followed by those on warfarin with a therapeutic intensity and those on only anti-platelet (p < 0.05). Multivariate analysis demonstrated that the NIHSS score was significantly low in the patients on warfarin with a therapeutic intensity (B, –5.602; 95% confidence interval [CI], –8.636 to –2.568; p < 0.001) or those on standard-dosed NOACs (B, –3.588; 95% CI, –6.405 to –0.771; p = 0.013), while there was no difference in the NIHSS score between the patients not taking any anti-thrombotics and those on warfarin with a sub-therapeutic intensity or under-dosed NOACs.

Conclusion Use of warfarin with a therapeutic intensity or standard-dosed NOACs was associated with a relatively mild stroke in the patients with NVAF.
The Effect of Intrapartum Vancomycin on Vaginal Group B Streptococcus Colony Counts
Authors: Hamel Maureen , Has Phinnara , Datkhaeva Ilina , Delacy Kimberly , Ciolfi Dana , Hughes Brenna
Published: November 2018

Objective To define the temporal relationship between intrapartum intravenous vancomycin administration and vaginal group B streptococcus (GBS) colony counts.

Study Design Prospective cohort study conducted from October 2014 to February 2017. Women with antenatal cultures demonstrating GBS colonization and a plan for vancomycin administration were eligible. Intrapartum vaginal cultures were collected prior to the first vancomycin infusion and every 2 hours up to five collections or delivery. Results were analyzed in two groups: participants with at least one positive intrapartum culture and those without any positive intrapartum cultures.

Results A total of 63 women were enrolled. Among consented women, a total of 8 were excluded and 3 participants' cultures were never plated, thus leaving a total of 52 women for analysis. The degree of vaginal GBS colonization varied between subjects and was not normally distributed. Colony counts dropped rapidly from hour 0 to hour 2 (median: 6.0 × 108 vs. 1.0 × 108, p < 0.01). Standardizing hour 0 colony counts to 100%, the percent decline in colony counts from hour 0 to hour 2 was significant (p = 0.03), and at each subsequent time point fell further.

Conclusion GBS vaginal colony counts fall rapidly after intrapartum vancomycin administration.
Interference sensor for ultra-precision measurement of laser beam angular deflection
Authors: Dobosz Marek
Published: November 2018

A new interference sensor for ultra-precise measurement of laser beam angular deflection is proposed. The angular tilt of the measuring device, in relation to the beam axis, can also be measured. The theoretical basis of the angle evaluation presented is based upon analyzing the fringe period, as well as the suggested optical setup and design of the device. Calculating algorithms for the evaluation of the beam angle change, the influence of the fringe phase on angle measurement, and the metrological feasibilities are also detailed herein. The main source of measurement errors is explored, and the influence of the sensor’s positioning procedure in relation to the laser beam on the repeatability of the processing function is statistically analyzed. The results show that the sensor resolution reaches 25 nrad with an accuracy better than 1% in the measuring range 350 µrad. Finally, the potential applications of the interference sensor are described.