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Gait recognition is a new biometric technology to identify different users through gait data. In this paper, a novel CC-LSTM-CNN gait recognition method is proposed based on the cross-correlation (CC) algorithm and the Long Short-Term Memory convolutional neural network (LSTM-CNN) hybrid classification model. The 3D cross-correlation features of X axis, Y axis and Z axis acceleration signals are calculated by cross-correlation algorithm, and the main features are extracted by Principal Component Analysis. Then LSTM-CNN hybrid model is designed to train the feature data series and get the CC-LSTM-CNN model. The results show that the accuracy for identifying different user reaches 99.3% thru gait data in 5 seconds. The result is significantly improved compared with the traditional machine learning classification algorithm.

Biomethane upgraded from biogas had been proven as a potential renewable energy. Utilizing the metabolic activity of enriched hydrogenotrophic methanogens was regarded as a new way to upgra...

Radiation therapy is among the top three cancer treatments in current medical services. The novel noncoplanar radiation therapy which claimed the best characteristics in almost all dosimetric properties encountered the challenges of the potential collision and the long time delivering. In this paper, we proposed a brand new scheme which uses a combined method of the collision avoidance path planning based on an improved probability roadmap method (PRM) and the delivery sequence optimization based on a modified genetic algorithm (GA) to solve the problems in noncoplanar radiation therapy. A uniform sampling strategy, an improved connection strategy, and an efficient local planner are introduced to optimize the roadmap result and accelerate the roadmap construction. The GA is improved by the elitist selection, the local search strategy, and the similar substitution strategy to achieve a better performance both in convergence rate and optimal solution. Experiments are carried out on the simulation platform with typical therapy system models. The results show that our proposed methods work well with the radiation therapy system in a compact working area. Collision is avoided and time consumption is reduced. We believe that our proposed algorithms could solve the problems in current radiation therapy and promote their clinic applications.

Spray drift from aerial application is a great concern and there have been many efforts to predict it. Here computational fluid dynamics (CFD) techniques are used to predict the velocity field and the subsequent trajectories of spray droplets in the wake of a Thrush 510G aircraft. The fluid phase is modelled using the Reynolds-averaged Navier–Stokes (RANS) equations within an Eulerian frame, whilst the dispersed phase is modelled using a stochastic tracking model in the Lagrangian frame. The wake of aircraft is represented with a pair of wing-tip vortices and droplets are released in ten locations representing atomisers mounted below the wing. Firstly, a case without the presence of crosswind was simulated and deposition analysis was performed. A case with the presence of crosswind was then simulated to predict spray drift and deposition. The locations droplets at different times, as well as evaporation rate, were compared with AGDISP (agricultural dispersal model) predictions. The physics of vortices evolution, droplets motion and evaporation were analysed to explain the drift and deposition characteristics.

The technologies for testing and analyzing aerial spray deposition and drift serve as the tools and foundational technologies for spray deposition and drift modeling, deposition and drift control, and the development of aerial spray equipment. These technologies can be categorized into four types by comprehensively considering their testing analysis methods, analysis objects, and application technologies: sampling, laboratory simulation, computer simulation modeling, and new analysis technologies. With regard to sampling analysis technologies, this study mainly analyzed the water-sensitive paper (WSP) sampling testing method, tracer testing method, combined WSP and tracer testing method, as well as the electronic information technologies that have been widely used and rapidly developed in recent years. With respect to the laboratory simulation analysis technologies, this paper elaborates on the applications of laser particle size measurement technology and instrument based on the laser diffraction principle, particle image velocimetry technology and instrument, phase doppler interferometer based on laser scattering principle, and other spray measurement technologies. In case of computational modeling simulation analysis technologies, this paper mainly expounds the spray deposition model analysis and research methods based on the Gaussian plume, Lagrange, statistical, and computational fluid dynamics (CFD) models. Additionally, the paper describes the applications of LIDAR, thermal infrared imaging, and other technologies to the analysis of spray deposition. Electronic technology, computer technology, and other information technologies are being used more widely for analyzing aerial spray deposition, and have become a development trend in recent years. The instruments rapid measurement of spray deposition in the field and the real-time accurate prediction models for spray drift are in high demand. The instrument for rapid in-field measurement should be compact, exhibit good portability and convenience of use in the field, and guarantee high measurement accuracy. The spray deposition and drift mechanisms are relatively well clarified, and the use of advanced technologies to develop practical instrument is the main work of future research in this area. Keywords: aerial application, deposit measurement, drift monitor, plant protection DOI:  10.33440/j.ijpaa.20200302.80  Citation: Zhang R R, Chen L P, Wen Y, Tang Q, Li L L.  Key technologies for testing and analyzing aerial spray deposition and drift: A comprehensive review.  Int J Precis Agric Aviat, 2020; 3(2): 13–27.

Branded mobile applications (apps) serve as useful marketing tools to assist existing and potential customers and greatly motivate consumers to engage with brands. This paper aims to investigate how branded apps achieve consumer continuance intention from the perspective of consumer–brand engagement (CBE). Data are collected from 509 users of Chinese branded mobile applications and analyzed using a structural equation model. Results showed three dimensions of CBE that have unique interrelationships that promote continuance intention. Perceived informational usefulness serve as a utilitarian motivation, while perceived entertainment and social presence as hedonic motivations, all contributing to CBE in different ways.

Serial Elastic Actuator (SEA) system attracts much attention recent years in robotics research. The control methods for SEA is studied especially considering the unknown and time-varying dynamic load. Most methods are based on the predetermined nominal dynamics of the SEA system. However, imperfect dynamics and time varying reference torque make the torque tracking problem difficult. In this paper, the Active Disturbance Rejection Control (ADRC) method is proposed to solve the above problems. The dynamics of SEA is simplified by considering the dynamics of load as the unknown disturbance. An Extended State Observer (ESO) is designed to identify the model uncertainties. The control framework could observe and reject the disturbance effectively. Finally, the effectiveness of the ADRC based torque controller is verified and compared with traditional cascade PID controller by using MATLAB/ADAMS Co-simulation, especially considering the case that SEA is implemented in a vertical plane which makes the dynamics much more complicated.

A study of the velocity field of the wake of a Thrush 510G carrying out spray application close to the ground was investigated. The aircraft normally operates in extreme ground effect and wake vortices play a major role in the dispersal and deposition of pesticide spray released behind the aircraft. The evolution of wake vortices over time, and their interaction with the ground were simulated using computational fluid dynamics (CFD) techniques. The simulation was initialised with meteorological data from a field experiment. Information given by CFD simulation included the trajectory of the wake vortices as well as circulation, which indicates the strength of vortex. This information provided insights into the velocity field in the wake, including the upwash near the wing tips and the downwash in between. The effect of turbulence intensity as well as crosswind on the wake vortices and the resulting velocity field were investigated.

Unmanned helicopters are used widely in precision agriculture, especially in East Asia. However, the development of the downwash flow field of unmanned helicopters, which strongly influences the movement of spray droplets in the air, is poorly understood. Therefore, an indoor measurement technique was developed to investigate the downwash flow field of a 1:10 scaled unmanned agricultural helicopter (AF-25B; Copterworks). High-speed particle image velocimetry was employed to obtain the instantaneous and average velocity field of the downwash flow, with a spatial resolution less than 0.005 m and temporal resolution less than 0.001 s. Results showed that radial distance of the point at which downwash flow reached the ground was proportional to the hovering height of the helicopter at a hovering height of z/R

How to improve the resource utilization of the cloud computing system has been one of the key content of the research of the cloud computing. The traditional multi-objective ant colony optimization was improved, studied the virtual machine live migration framework, combined with the elimination method to solve virtual machine migration and placement of multi-objective optimization problem, the load balanced specific strategies are integrated into the framework of a dynamic migration, simulation experiments are carried out and the conclusions are made for it. The algorithm can obtain the optimal solution through the continuous updating of pheromone. The main consideration is the Service level contract violation rate(S), Resource loss(W),Power consumption (P). Experimental results show that ,compared with the traditional heuristic method and genetic algorithm, the algorithm is advantageous to the parallel computation, and it’s able to achieve the optimal tradeoff and compromise between multiple conflicting objectives. In the case of service level contract violation rate is low, system resource waste and power consumption are at the least, so it has feasibility.

Real-time relative height measurement is very important for control system of agricultural plant protection UAV. In the paper we research a multi-sensor relative height fusion algorithm which combined radio altimeter, barometric altimeter, GPS satellite navigation receiver and inertial measurement unit. According to association with GPS speed value, a method which base variable coefficient is proposed to eliminate outlier errors of radio altimeter and an algorithm based half-step interpolation is used to reconstruct the radio altimeter data. A Kalman filter is used for fusion the multisensors measurement value and give the optimal estimation of relative height of UAV. Through the experiment data, the method can eliminate 95% outlier error, and the height measurement error is reduced to 0.15m. The method can be used in super low-altitude plant protection UAV flight control system.

Purpose – The purpose of this paper is to design the localization and tracking algorithms for our mobile welding robot to carry out the large steel structure welding operations in industrial environment. Design/methodology/approach – Extended Kalman filter, considering the bicycle-modeled robot, is adopted in the localization algorithm. The position and orientation of our mobile welding robot is estimated using the feedback of the laser sensor and the robot motion commands history. A backstepping variable is involved in the tracking algorithm. By introducing a specifically selected Lyapunov function, we proved the tracking algorithm using Barbalat Lemma, which leads the errors of estimated robot states to converge to zero. Findings – The experiments show that the proposed localization method is fast and accurate and the tracking algorithm is robust to track straight lines, circles and other typical industrial curve shapes. The proposed localization and tracking algorithm could be used, but not limited to the mobile welding. Originality/value – Localization problem which is neglected in previous research is very important in mobile welding. The proposed localization algorithm could estimate the robot states timely and accurately, and no additional sensors are needed. Furthermore, using the estimated robot states, we proposed and proved a tracking algorithm for bicycle-modeled mobile robots which could be used in welding as well as other industrial operation scenarios.

Replica exchange molecular dynamics (REMD) is a popular method to accelerate conformational sampling of complex molecular systems. The idea is to run several replicas of the system in parallel at different temperatures that are swapped periodically. These swaps are typically attempted every few MD steps and accepted or rejected according to a Metropolis–Hastings criterion. This guarantees that the joint distribution of the composite system of replicas is the normalized sum of the symmetrized product of the canonical distributions of these replicas at the different temperatures. Here we propose a different implementation of REMD in which ( i ) the swaps obey a continuous-time Markov jump process implemented via Gillespie’s stochastic simulation algorithm (SSA), which also samples exactly the aforementioned joint distribution and has the advantage of being rejection free, and ( ii ) this REMD-SSA is combined with the heterogeneous multiscale method to accelerate the rate of the swaps and reach the so-called infinite-swap limit that is known to optimize sampling efficiency. The method is easy to implement and can be trivially parallelized. Here we illustrate its accuracy and efficiency on the examples of alanine dipeptide in vacuum and C-terminal β-hairpin of protein G in explicit solvent. In this latter example, our results indicate that the landscape of the protein is a triple funnel with two folded structures and one misfolded structure that are stabilized by H-bonds.

In the afterheat recovery process, the heat pump has high request to the heat-source water’s temperature stability. This article uses the method of temperature constant and frequency variable to guarantee the stability of heat-source water. However, the afterheat recovery system is a dynamic engineering system and the parameters of normal PID can not real-time tuning, it has bad Control effect. Therefore, this article combines fuzzy control and PID control to get a fuzzy PID controller with its parameters can be tuned to improve the adaptation ability for the time-varying of parameters. And we use it to improve the performance of steady and dynamic states for the controlled object. Modeling and simulating to the system by the Simulink and the fuzzy toolbox in the MATLAB and examining the control effect of the system.

Background Blood loss during liver resection and the need for perioperative blood transfusions have negative impact on perioperative morbidity, mortality, and long-term outcomes. Methods A randomized controlled trial was performed on patients undergoing liver resection comparing hemihepatic vascular inflow occlusion, main portal vein inflow occlusion, and Pringle maneuver. The primary endpoints were intraoperative blood loss and postoperative liver injury. The secondary outcomes were operating time, morbidity, and mortality. Results A total of 180 patients were randomized into 3 groups according to the technique used for inflow occlusion during hepatectomy: the hemihepatic vascular inflow occlusion group (n = 60), the main portal vein inflow occlusion group (n = 60), and the Pringle maneuver group (n = 60). Only 1 patient in the hemihepatic vascular occlusion group required conversion to the Pringle maneuver because of technical difficulty. The Pringle maneuver group showed a significantly shorter operating time. There were no significant differences between the 3 groups in intraoperative blood loss and perioperative mortality. The degree of postoperative liver injury and complication rates were significantly higher in the Pringle maneuver group, resulting in a significantly longer hospital stay. Conclusions All 3 vascular inflow occlusion techniques were safe and efficacious in reducing blood loss. Patients subjected to hemihepatic vascular inflow occlusion, or main portal vein inflow occlusion responded better than those with Pringle maneuver in terms of earlier recovery of postoperative liver function. As hemihepatic vascular inflow occlusion was technically easier than main portal vein inflow occlusion, it is recommended.

At present, the return of farmland to forests is the key ecological conservation policy in use to control soil erosion and restore the eco-environment of the Loess Plateau, China. In order to explore policy-driven ecological defarming scenarios, Ansei County is taken as a case study. The land use map in 2000 and the topographic and slope map (taking the defarmed slopes with 15 degrees, 20 degrees, and 25 degrees as the do farming thresholds) were used, supported by spatial analysis techniques in geographic information systems (GIS). This paper simulates and analyzes the scale and spatial difference of ecological defaming of Ansai County, the subsidy demand for deforming, and the influences of deforming on agricultural development. The results show: (1) The area of do farmed land with slopes greater than 25 degrees in Ansai amounts to 3451.05 ha, which accounts for 2.84% of total area with slopes over 25 degrees, and the defarming index will be 3.14%. The total subsidy demand for deforming land will be 6884.84 x 10(4) yuan (RMB) or US$ 1008.03 x 10(4). The loss of agricultural food products that results from defarming will be 955.17 t in the average year, or 1.66% of total average annual production. (2) The area of defamed land with slopes over 20 degrees in Ansai will increase to 36,281.61 ha, which accounts for 19.74% of total area with slopes over 20 degrees, and the defarming index will be 32.96%. The total subsidy demand for do farming land will be 72,381.81 x 10(4) yuan or US$ 10,597.63 x 10(4). The loss of agricultural food products due to deforming will be 10,041.9 t in the average year, or 17.50% of total average annual production. (3) The area of do farmed land with slopes over 15 degrees in Ansai increases to 101,807.99 ha, which accounts for 37.23% of total area with slopes over 15 degrees, and the defarming index will be 92.49%. The total subsidy demand for deforming land will be 203,106.94 x 10(4) yuan or US$ 29,737.47 x 10(4). The loss of agricultural food products owing to defarming will be 28,178.06 t in the average year, or 49.10% of total average annual production.

SUMMARYThis paper analyzes the stabilization problem from the energy point of view. Perturbations are detected by the gyros and categorized according to the constraints on the zero-moment point, energy, and walking pattern. Ankle torque is exerted to extend the linear inverted pendulum mode (LIPM). Compensation movement is computed according to the analysis on the energy of LIPM and the influence of disturbance to the energy. The experimental results from both the simulation and the physical robot not only proved effective but also explain various human reactions to disturbance in locomotion.

De-farming has been a powerful measure taken by the central and local governments of China for ecological restoration in the loess hilly-gully region since 2000. In years past, aid-based de-farming pattern was far and wide popularized in the region and terrace-based de-farming pattern demonstrated in a few small watersheds was also rather effective for ecological restoration. After summing up the features of three patterns (aid-based de-farming slope farmland more than 25° (AD25), aid-based de-farming slope farmland more than 15° (AD15) and terrace-based de-farming (TD)), this paper analyzed the regional difference of these patterns in de-farming area, ecological restoration, investment demand and so on. The results show that there are two crucial areas in the loess hilly-gully region for ecological restoration at the moment, the policies adaptation to the different areas should be constituted as soon as possible and the limited fund should be devoted to the two crucial areas.

Objective Obesity is a major public health problem. Regulating food intake and promoting metabolism of fat are two important options for treating obesity. Auricular vagus nerve stimulation (AVNS) is considered as an alternative approach to vagal nerve stimulation. The aim of this study was to investigate the effects of AVNS and its mechanisms on obesity in obese rats. Methods Male Sprague-Dawley rats were fed either a high-fat diet (HFD) or a normal diet for 8 wk. Qualified HFD rats were randomly divided into three groups: the HFD group, the AVNS group, and the sham group for 6 wk treatment. Body weight and daily energy intake were recorded weekly. The rats were sacrificed for measurement of weight of bilateral perirenal, epididymal white adipose tissue (WAT), dorsal brown adipose tissue (BAT), and gastric emptying. Serum cholecystokinin (CCK), peptide YY 3 to 36 (PYY 3–36 ) and norepinephrine (NE) were assayed by enzyme-linked immunosorbent assay. Real-time quantitative polymerase chain reaction was used to assess the mRNA expressions of CCK subtype receptor a (CCKa) in the antrum, PYY 3–36 receptor in the distal ileum, β 3 -adrenoceptor, and uncoupling protein gene 1 ( UCP1 ) in the BAT. Results Compared with HFD group, AVNS significantly reduced body weight and epididymal WAT and increased BAT weight, serum NE, mRNA expressions of β 3 -adrenoceptors, and UCP1 of the BAT, but had no effect on daily energy intake, perirenal WAT weight, gastric emptying, serum levels of CCK and PYY, or mRNA expressions of CCKa receptor and PYY 3–36 receptor in the relevant tissues. The sham group, as a comparison group for AVNS, saw less effect in any of the indexes compared with the HFD group. AVNS had more effect on weight loss, reduction of perirenal WAT, and increase of NE, β 3 -adrenoceptor, and UCP1 than sham. Conclusions AVNS was more effective in reducing body weight and causing visceral fat loss. Biochemical tests found more NE released in the serum and more β 3 -adrenoceptor and UCP1 expression in the BAT. All of these features suggested that energy expenditure might play an important role in obesity management by AVNS.

Aiming at multi-channel video capturing of the system of video acquisition, this paper proposed a simple configuration scheme of the decoder chip TVP5154. It introduces the protocol of IIC and the setting methods of registers of the decoder chip TVP5154. It uses the hardware description language veriglog to control IIC bus. This process can initialize the decoder TVP5154 after power up or reset. The results show that the configuration of TVP5154 can capture video data of four channels at the same time in the same manner and finish video decoding.

This article starts from the function of financial market of amassing, allocating, regulating and reflecting and explores the mechanism of financial support on industrial transfer. It finds out that the financial support takes effect in four ways: filling the capital gap, guiding the transfer direction, building the transfer environment and reducing the transfer risk. On this basis, constructs an evaluation index system of financial support degree on industrial transfer. With this system, you can prepare the comprehensive index of financial support degree of different areas or industries and find out the existing problems. So that can improve the efficiency of supporting, promote industrial transfer and realize the optimization of industrial structure.

Based on the researches of software component and the performance-sensitive characteristic of hardware component used in core router, a model of hardware component is proposed. And then, a formal description of this model, including function, resource consumption and performance (the most important one), is built up. At last, according to the model proposed in this paper, a congestion control component is designed.

A design of video capture system based on FPGA is presented in this paper. This paper describes the working principle of the system and hardware architecture and it analyzes the composition of the system modules and the design methods in detail. This paper also gives a detailed analysis of each implementation technology of the system, and the system meets the needs of the back-end of video processing. It also displays simulation experiment result. The simulation experiment result shows that this design meets the requirement.

Individual decision making determines critical outcomes for organizations in various domains including information security, where the increase of security incidents is causing great concern to organizations. Information security awareness programs are an important approach towards educating users to prevent such incidents. However, it is unclear how to effectively design security programs and messages such that they can inform and change user behavior. This paper attempts to investigate this problem by studying the effects of security message characteristics on users, using the decision-making theory of elaboration likelihood. A 2×2 factorial design experiment was conducted to determine the influence of message repetition and message comprehensibility on user’s elaboration likelihood towards a security message. Our findings indicate that message repetition enhances elaboration likelihood of users. Message comprehensibility interacts with message repetition in determining elaboration likelihood. The results have implications for designing effective security messages and for decision support systems for this purpose.

The optical nonlinearities of an Ag nanoparticle array are investigated by performing Z-scan measurements at the selected wavelengths (400, 600, 650, and 800 nm). The nonlinear refraction index in the resonant region (around 400 nm) exhibits a significant enhancement by two orders compared with that in the off-resonant region (around 800 nm)), and exhibits an sign alternation of the resonant nonlinear absorption, which results in a negligible nonlinear absorption at a certain excitation intensity. Moreover, a low degree of nonlinear absorption was measured at the edges of the resonant region (600 and 650 nm), which is attributed to the competition of the saturated absorption and the two-photon absorption processes.

Wave-particle duality is one of the most fundamental and mysterious natures of matters. Here, we present an interesting scheme of isolated electron wave packet diffraction with a few-cycle laser pulse and an extreme ultraviolet (XUV) pulse. The diffraction fringes are clearly present in the laser dressed XUV photoelectron spectra, strongly resembling the Airy diffraction pattern of optical waves. This phenomenon suggests a great potential of attosecond diffractometry. According to this scheme we also propose a simple method to determine the XUV pulse duration from the photoelectron spectra with a rather high resolution.

By solving the one-dimensional time-dependent Schr?dinger equation with split-operator method, we study the high harmonics generated by helium atom, and analyse the characteristics of the attosecond pulses generated by the high-order harmonics. By adopting a mid-infrared driving pulse (with wavelength of 2000 nm and pulse duration of 12.5 fs) combined with a short UV controlling pulse, a smooth supercontinuum with the bandwidth of 230 eV is observed. By adjusting the delay between the mid-infrared and ultraviolet fields, the contribution of the short quantum trajectory can be efficiently enhanced and an isolated 100 as pulse seems achievable. We found that the supercontinuum is not sensitive to the intensities of the two lasers, which facilitates the experimental implementation for the isolated attosecond pulse generation.

On the basis of optical resilient packet ring (O-RPR), this paper analyzes the control optical power needed for dual loop optical buffer (DLOB) to achieves ‘write-read’ successfully, and discusses the influencing factors on this power. Then we discuss the pulse compression and chirp caused by the signal pulse not being ideally square, and analyze the influence of power fluctuation and signal-to-noise ratio(SNR) of control light on output data.