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Traditional animation needs complex animation technology, which is mainly operated by hand. Therefore, traditional animation production needs a lot of work, which will lead to a variety of problems, such as long cycle, high rework rate, high cost and so on. With the development of computer technology, great changes have taken place in animation production, including speed, effect, etc., which has created a variety of methods in two-dimensional and three-dimensional animation production. Through computer-aided, the traditional manual animation technology has been gradually replaced by computer, which has become a key issue in animation art production. By combining the advantages of manual animation and computer animation, we can continuously improve the ability of animation industry. Through the synthesis editor, we can improve the animation action and accelerate technology research, which can achieve a new animation world. First of all, this paper analyzes the commonly used 3D animation production software. Then, this paper analyzes the animation action and acceleration technology.

In this paper we critically examine a concept which we term the ‘ponderomotive snowplow’. It has been alluded to by a number of authors, but a complete description is given by Sazegari et al (2006 Phys. Plasmas 13 033102). In this paper we present a critical analysis of this concept. As a strictly model problem, this is a valid idea. However it does not account for the longitudinal electrostatic field that must be generated in an actual laser-plasma interaction. Both analytic and numerical investigations indicate that the effects of this are hard to neglect, and lead to an effective ponderomotive snowplow that works—as described by Sazegari—as an effective electron accelerator being hard to realize.

In the past, the horizontal sealing mechanism of the bulk material packaging machine has a cam type and a cylinder type. The cylinder type horizontal sealing mechanism has a great impact when the speed changes, while the cam type horizontal sealing mechanism will cause noise and vibration. In this paper, the three-dimensional model of horizontal sealing device for bulk material packaging machine is carried out by SOLIDWORKS software, and the motion simulation analysis is carried out by using the add-in SOLIDWORKS motion. The results show that the acceleration of the horizontal sealing head for the horizontal sealing device occurs in 1/4 and 3/4 of the entire movement cycle. The horizontal sealing device can adjust the speed to meet the horizontal sealing requirements of different packaging bags. The horizontal sealing device of the bulk material packaging machine designed in this paper provides a reference for improving the packaging efficiency of products.

The paper deals with the planar problem of vibration isolation. The active vibration damper is mounted on an oscillating mass with a vibroactive unit at a point that does not coincide with the mass center and the action of the vibroactive force does not coincide with the mass center. An active dynamic vibration damper is an electrodynamic drive in which the translational movement of the moving mass is carried out according to information about acceleration from an accelerometer mounted on an oscillating mass with a vibroactive unit. The paper gives an assessment of the vibration isolation effectiveness, depending on the mismatch with the mass center of the vibrational force application points, the settings of the active damper and accelerometer.

Aimed at intelligent vehicles operating in complex driving environment, the paper is described on the basis that the reference trajectory has been determined. According to the vehicle running state and obstacle information, the vehicle’s running track can be adjusted in real time to solve the path planning problem and according to the re-planned reference track, the following control is carried out in the paper to avoid obstacles. Firstly, a point mass model is established which ignores the car body size. Secondly, on the premise that the size of obstacles is smaller than the car body size, according to the obstacle information obtained by the sensor and the established point mass model, the obstacle avoidance penalty function is established, then the objective function of the path planner is established. Finally, two working conditions: single obstacle and two obstacles, are set up to simulate and verify the designed obstacle avoidance trajectory following system. By observing the distance between the actual track and obstacles under different simulated speeds, varied range of front wheel angle and centre of mass side deflection angle, different range of angular velocity of lateral swing and lateral acceleration to verify whether the vehicles can successfully avoid obstacles with different speed and numbers of obstacles in order to maintain good driving stability in the process. Simulation results show that, under the control of the path following system added to the planning layer, intelligent vehicles in a complex driving environment can autonomously plan their paths, avoid obstacles, follow the path, and ensure good driving stability meanwhile.

Horizontal forces between the crane and the crane runway girder occur during a motion of an overhead travelling crane on the crane runway. There are several methods for calculation of these forces. The most significant load caused by motion of crane is the skewing and the acceleration of the crane and of the crab. This paper deals with the acceleration of the crane and with the skewing of the crane. In present the skewing of crane is defined as the motion of the overhead bridge crane with the constant velocity but with the angle relative to the crane runway. The transverse forces caused by acceleration of the crane are calculated separately. But the skewing of the crane can occur also during the accelerating of the crane. Present standards don’t take this situation into account. A dynamical model presented in this paper describes motion of the overhead double bridge crane during its acceleration. The basic assumption of this model is that there the contact between the rim of the firs crane wheel and the rail of the crane runway.

This study was conducted to develop a simple and inexpensive experimental apparatus that can measure the position of an object moving along a straight line at certain time intervals. For the construction of the apparatus, a battery-powered toy car, a fine-tipped paint brush, gouache (or watercolour) paint and paper tape were used. The working principle of the device is this: a short time after the toy car is turned on, its wheels start to turn with a constant angular velocity. A paint brush attached to one wheel also turns with a constant angular velocity. The paper tape is placed at a distance where the brush can touch it. Thus, with each round of the wheel, the brush lightly touches the paper tape and leaves a paint mark. Since the wheel turns at a constant angular velocity, the brush touches the tape once in each turn and leaves behind an equal amount of paint at equal intervals (one cycle at (T) time intervals). When the paper tape is pulled by attaching it to the object for which the motion is to be analyzed, lines are formed on the paper. By measuring the distance between the lines, the motion of the object can be analyzed and the position of the object can be identified at various moments. In this way, the speed and acceleration of the object can be measured.

The paper deals with the impact of shocks on cargo securing during the road freight transport. Commonly used methods of cargo securing do not take into account the different quality of roads, therefore the cargo securing doesn´t have to comply with principles of safe fastening. The paper highligths the different values of shocks and inertia forces on different quality roads (highway and 3rd class road) based on data of conducted transport experiments. The resulting shocks (values of acceleration coefficients) are statistically significantly higher on 3rd class road than on highway even at half average speed. The optimization of calculation using acceleration coefficients and their correlation with the resulting inertia forces is included in separated part. The output of the paper is a methodical procedure to optimize the cargo securing during the road transport.

An algorithm for acceleration/deceleration control is proposed in this paper to improve the flexibility of the heavy-duty motion system. The algorithm is based on the five-segment S-type acceleration/deceleration curve. During the acceleration switching time, a circular arc is used to smooth the curve, and the running time of each stage could be reasonably allocated by cyclic iteration. A parameter is defined to quantify the degree of flexibility of the acceleration/deceleration process to match the actual project. This paper will build the model to compare the good and bad point of different algorithms. The result shows that the vibration and impact during the acceleration and deceleration process can be effectively reduced, which means that the flexibility of the system has been greatly improved.

The current temperature field model of plate rolling process is generally based on CPU programming, due to the influence of computer performance, the accuracy and speed of the model can not be improved at the same time. To solve this problem, this paper studies the temperature field model with particle swarm optimization to modify the heat transfer coefficients, and the parallel program of this model is written under CUDA architecture, on premise of ensuring the accuracy of the model, the computation speed of the model is improved. To get the best acceleration, this paper analyzes the factors affecting GPU performance, the accuracy and speed of the temperature field model before and after modification are compared under the best acceleration configuration. Final temperature field model calculation error reduced to an average of 15.57 °C, better than the model based on the empirical formula, the computing speed is also improved, which is 1.78 times that of CPU.

The engineering technology of deep foundation pit support is complex and comprehensive, and it is necessary to consider the relationship between safety and engineering cost, and the optimal design of foundation pit support is especially important. Anchor support is a common support way for deep foundation pit support, in allusion to the shortcomings of particle swarm optimization; this paper adopts genetic algorithm, step length acceleration method and improved particle swarm optimization to carry out optimal design for foundation pit anchor support. The optimization results show that the combination with genetic algorithm improves the diversity of particle populations, the particle swarm optimization combined with the step length acceleration method has faster convergence performance, and the mathematical model of anchor supporting structure design is established. Through the case study of the foundation pit support of the super-high-rise building with frame shear wall structure, it was found that the engineering cost of the improved anchor support scheme after the improved particle swarm optimization is lower. The research in this paper provides a mathematical model for foundation anchor support.

Deep networks have achieved great success in many areas in recent years. However, with the increasing sophistication of deep neural networks (DNNs), the memory consumption and computational cost expand exponentially, greatly hindering their application in mobile devices and other limited resources. Therefore, there is impending necessity to consider model compression and acceleration without affecting the inference accuracy. In this paper, we review the recent popular techniques for compressing and accelerating deep networks. Those methods could be broadly divided into four categories: parameter pruning and sharing, low rank approximation, sparse regularization constraints and network weight low-bit quantization. The advantages and disadvantages of different compression and acceleration methods are also described in detail, other types of approach are also introduced in our paper, and future prospects for the field are given finally.

The shaking table test is an irreversible process for a nonlinear model structure. Therefore, how to choose ground motion and determine the input sequence are particularly important for the success of the shaking table test. In this paper, a 1/4 scale CFRP reinforced concrete frame structure specimen model is designed and made according to the similarity theory. By using the finite element analysis software SAP2000, the finite element model of CFRP reinforced concrete frame specimen is established. Four seismic waves are selected in the simulated shaking table test process, and the dynamic time history analysis of a total of 52 working conditions is carried out, including unidirectional, bidirectional and three-directional ground motion input, and the acceleration and displacement response of the structure are obtained. Taking story drift ratio as the evaluation index, the seismic performance of the structure is evaluated. This paper provides theoretical guidance for the subsequent shaking table test.

In this paper, the driver’s seatbelt detection algorithm is transplanted to the PYNQ embedded platform of XILINX to meet the technical requirements of automatic identification and detection of whether the driver wears a seatbelt or not. In this paper, aiming at the characteristics of the hardware of the FPGA, the driver’s seatbelt detection algorithm is realized by IP core from XILINX open source. Vehicle detection is realized by using YOLO object detection algorithm with 3 bit weight and 1 bit activation, and driver’s seatbelt classification is realized by using binary model with 1 bit weight and 1 bit activation. On the PYNQ embedded hardware of XILINX, the acceleration of the algorithm is realized by calling the hardware of FPGA on the ARM side.

With the acceleration of urbanization, more and more large-scale deep foundation pit projects are being carried out in the city. Due to the requirements of site and construction technology, it is necessary to design a supporting form that can be used as a supporting system without affecting the construction. In this paper, the large open ring beam structure is proposed as the supporting system, and the direct beam supporting system and the proposed ring beam supporting system are analyzed by finite element method. The structure shows that the ring beam structure proposed in this paper has better effect. The support form proposed in this paper provides an effective reference for design and optimization of foundation pit support form.

The vibration of perforated plate contains various complex physical phenomena in the fluid field, which is a key issue in fluid-structure interaction. Perforated plates have been widely used in power plants but the flow induced noise and vibration may give arise to some serious adverse impact. Therefore, it is of great significance to clarify the random vibration characteristics and noise problem of perforated plates in parallel flow. In this paper, the perforated plates were experimentally studied in a wind tunnel. Acceleration signal sensors are used to analyze the displacement and deformation of perforated plates and the pressure signals are measured by SETRA C266 micro pressure differential sensor, and the pulsating characteristics of perforated plates are analyzed by fast fourier transform (FFT), respectively. Through the analysis, it is found that the main pressure fluctuations of the flow direction are concentrated in the middle position and the tail. And the pressure fluctuations on the left and right sides of the perforated plates is very close in the spanwise position, and less than the center. Some key factors on the random vibration of perforated plates are discussed including wind velocity, hole diameter, hole pitch, plate thickness and the clearance height between the perforated plate and the cavity (It is means back space gap height). The analysis of the results indicated the impact of each factor. In detail, lower wind velocity and smaller hole diameter are beneficial to reduce the random vibration of perforated plate, however, larger hole pitch size and larger plate thickness are favorable to reduce the random vibration. The test results of this paper can provide a basis for the design of perforated plates.

In this paper, a miniaturized electron optic tracking system (EOTS) is proposed to improve the disturbance suppression performance when attached to near space aerostat. The electron optic tracking system, widely used in moving platforms can isolate the movement of the carrier and has high stability accuracy. However, the payload weight is limited for near space aerostats. The miniaturization of EOTS can effectively improve load distribution. To satisfy the demand of lightweight, micro-electro-mechanical system (MEMS) accelerometer is used in EOTS instead of fiber-optic gyroscopes (FOG). This paper employs position and acceleration double close-loop control method with MEMS linear accelerometer to improve the system performance especially in medium frequency. Meanwhile the disturbance observer (DOB) is introduced to suppress the measurably external disturbance. Furthermore, the disturbance performance of the EOTS is verified by MATLAB/Simulink. The results show that the improved miniaturized system can increase the payload of the aerostat effectively when the total load is limited.

In terms of the optimal power shift schedule of combined harvesting machinery, in order to improve the accuracy on solving optimal power shift points, this paper deduces the solving method to obtain the optimal power shift law of harvesting machinery based on the analyzing the characteristics of harvesting machinery. Two shift control parameters that have significant impacts on the optimal power shift point of harvesting machinery are put forward in the paper, namely the mass parameter and power distribution parameter. Taking the 4YZ-4- type combined maize harvester as an example, through the numerical calculation of MATLAB, it is found out that the change of mass parameter and power distribution parameters have significant impacts on the optimal power shift point. When the quality of harvesting machinery increases, the speed of the optimal power shift point will increase and the acceleration will decrease. When the power distribution coefficient of the driving axle of the harvesting machine increases, the corresponding speed at the optimal power shift point will decrease and the corresponding acceleration will increase.

The purpose of this paper is to highlight the analysis of the way in which the automobile can enter the state of instability when curving and the influence of some construction parameters (position of the weight centre, axle track, elasticity of the tires) and functional parameters (speed, acceleration, braking) which can influence the dynamic behavior. In this paper, there are described some dynamic simplified models of the automobile when curving, the way in which the experimental determinations have been made when a real automobile is involed in many circular routes with speeds and rays that we know. This paper also describes the methodology of study and the devices used as equipment for the automobile during the study on routes in order to register some specific parameters important for limiting the possibility of the appearance of lateral slips.

In this paper, we consider the Universe at the late stage of its evolution and deep inside the cell of uniformity. At these scales, we can consider the Universe to be filled with dust-like matter in the form of discretely distributed galaxies, a $K$-essence scalar field, playing the role of dark energy, and radiation as matter sources. We investigate such a Universe in the mechanical approach. This means that the peculiar velocities of the inhomogeneities (in the form of galaxies) as well as the fluctuations of the other perfect fluids are non-relativistic. Such fluids are designated as coupled because they are concentrated around the inhomogeneities. In the present paper, we investigate the conditions under which the $K$-essence scalar field with the most general form for its action can become coupled. We investigate at the background level three particular examples of the $K$-essence models: (i) the pure kinetic $K$-essence field, (ii) a $K$-essence with a constant speed of sound and (iii) the $K$-essence model with the Lagrangian $bX+cX^2-V(\phi)$. We demonstrate that if the $K$-essence is coupled, all these $K$-essence models take the form of multicomponent perfect fluids where one of the component is the cosmological constant. Therefore, they can provide the late-time cosmic acceleration and be simultaneously compatible with the mechanical approach., Comment: 26 pages, no figures. Conclusions extended and references updated. Version accepted in JCAP

With the development of structure optimization, building materials and construction technology, the study of the P-Δ effect is becoming more and more important in the pursuit of layers, flexibility and light quality. Based on the research status of P-Δ effect at home and abroad, this paper selects thenegative property fictitious member method to calculate the P-Δ effect of the multi-layer frame structure under the combined effect of horizontal and vertical ground motion. This paper discusses the influence of the stiffness-to-weight ratio, structural damping, and the vertical acceleration response of the structure. The results show that the damping and structural acceleration responses have a significant effect on the structural P-Δ effect. Under the premise of considering both, the stiffness-to-weight ratio of the structure, that is, the frequency of the structure, has a greater influence on the P-Δ effect of the structure under earthquakes. With the increase of the stiffness-to-weight ratio, the effect of P-Δ effect on structural response is increased and decreased.

When transmission lines pass through microtopographic area, the acceleration effect of wind speed should be taken into consideration during designing. However, the acceleration ratio coefficient of wind speed should not be selected simply according to mountain slope as specified by standards. In order to comprehensively consider the impact of wind direction and microtopography upon acceleration ratio of wind speed. This paper selects the acceleration ratios of wind speed at the height of 10m-120m in a tower position at 24 angles of direction wind by virtue of CFD simulation analysis. Combined with the line trend, this paper compares and calculates the change rule of wind loads on tower body and lead/ground wires after considering the pre/post-impact of acceleration ratio of wind speed. Through analysis, this paper forms suggestions on wind-resistant design for lead/ground wires in transmission lines in microtopographic area as well as accident analysis for reference.

This paper describes the possibility of estimating the health of a rail track in order to improve the comfort and ride quality of rail transportation by using the measured acceleration signal. The irregularities present in the track are the primary causes of vibration and these should be identified and the faults rectified to increase the safety of train travel. In this paper, a differential evolution technique based track measurement system (DE-TMS) is proposed to measure the health of the track. The abnormality of the track has been measured using micro electro mechanical system (MEMS) accelerometers which are mounted in the axle box. A new sensing method is used to estimate the exact location of the irregularity even when the signal is absent. The DE-TMS is simulated and compared with two other optimization techniques such as the particle swarm optimization technique and the covariance matrix adaptation with evolutionary strategy to evaluate the performance. The comparison results from the investigation show that the proposed DE-TMS provides cost-effective maintenance, and increase the safety of rail transportation. Finally, an experimental study was performed in four different irregularity cases and the results are estimated.

This paper proposes an efficient precision acceleration with temperature and humidity acquisition system based on 24-bit A/D Converter, IIC temperature and humidity sensor, Ethernet controller and microcontroller. This paper expounds in detail the realization of acquisition hardware, UDP protocol in microcontroller, the acquisition software as well as many other important aspects of the system. On the basis of the foregoing, build the entire acquisition system and apply it to the road roughness measuring instrument. Through the practice of the vehicle-mounted environment inspection, experimental results show that this system can stable operation for a long time and have a good application prospect.

The paper presents the results of the studies assessing the resistance of the existing bridge structures located in areas of varying seismic intensity. The basis for the analysis was an exemplary reinforced concrete road flyover of a slab span structure. Numerical calculations by the Finite Element Method were carried out, using the response spectrum approach in the dynamic analysis, with the use of the standard response spectra according to the Eurocode 1998 and the standard acceleration response spectra for the Upper Silesian Coal Basin and the Legnica-Glogow Copper District. For each individual analyzed case, the structure response to the assigned kinematic excitation was compared with the effects of load combinations adopted at the design stage, setting the limit values of the design horizontal ground acceleration in the horizontal plane (ag,H max ) and the vertical plane (ag,V max ). This allowed to assess the effect of seismicity of a specific area on the design dynamic resistance of the studied object. The paper discusses the manner of interpretation and the scope of applicability of the obtained results.

In this paper we present the synthesis of the cam for a distribution mechanism used for Miller-Atkinson cycle and described in previous works. The input data contain the angles at which the valve opens and closes, respectively, the dimensions of the main parts, the maximum displacement of the valve. and the law of motion of the valve. The authors consider that the law of motion of the valve is described by numerical values, even if in the simulation process they use analytical formulae for this displacement. The head of the valve is considered to be circular. A particular case of flat head of the valve is also described. The relative displacement of the lever and the valve is discussed in two hypotheses: symmetric position and asymmetric position of the contact point with respect to the axis of the valve. The contact between the head of the valve is assured by a cylindrical roller. The contact between the cam and the lever is considered with a roller tappet. In all cases the cam is obtained by numerical synthesis using a convenient angular degree. A great attention is paid to the convexity of the cam. The resulted cam is transformed in a convex one using the Jarvis March. The authors also perform a comparison between the theoretical profile of the cam and the profile of the convex cam. The reduced velocity and acceleration are obtained in all cases. Some aspects of the wear are discussed using the relative linear and angular velocities. The paper closes with a paragraph of conclusions.

Network reconfiguration for loss reduction in the distribution system is a significant way to save resources. It's an extremely hard optimization problem because of a plenty of switches in a distribution network. This paper presents an efficient Gravitational Search Algorithm (GSA) and its improvement based on elite strategy and adaptive position (ES-APGSA) to reduce grid loss using reconfiguration. The new algorithm can improve the speed of iterations and avoid the local convergence. In addition, the encoding method based on ring network is proposed which makes the dimensions of the particles much lower leading to an acceleration of the process. The correctness and effectiveness of the methods suggested in this paper is verified through the simulation results of IEEE33-node system.

This paper presents a thermal convection-based sensor, which is fabricated using carbon nanotube (CNT) yarn. The key element in this device is the non-symmetrically distributed, heated air medium around the heater, particularly when it experiences acceleration and/or changes in inclination. Therefore, it can withstand much higher accelerations/inclination than conventional sensors that use a proof mass. However, a major challenge for the design of this type of sensor is the high heating power (in the order of tens of milliwatts) required to facilitate thermal convection in a sealed chamber. In order to reduce the high heating power, CNTs are investigated as materials for both the heater and the temperature sensors. Moreover, this paper discusses experiments that were performed by varying several parameters, such as the heating power, distance between the heater and temperature sensors, the gas medium used, and air pressure.

The electric vehicles solutions based on the individually controlled electric motors propel a single wheel allow to improve the dynamic properties of the vehicle by varying the distribution of the driving torque. Most of the literature refer to the vehicles with a track typical for passenger cars. This paper examines whether the narrow vehicle (with a very small track) torque vectoring bring a noticeable change of the understeer characteristics and whether torque vectoring is possible to use in securing a narrow vehicle from roll over (roll mitigation). The paper contains road tests of the steering characteristics (steady state understeer characteristic quasi-static acceleration with a fixed steering wheel (SH = const) and on the constant radius track (R = const)) of the narrow vehicle. The vehicle understeer characteristic as a function of a power distribution is presented.

In this paper, a vibration-based MEMS electromagnetic energy harvester (EM-EH) device with two-degree-of-freedom (2DOF) configuration has been presented, modeled and characterized. The proposed 2DOF system comprises a primary subsystem for power generation, and an accessory subsystem for frequency tuning. A lumped parametric 2DOF model is built and examined in respect of energy harvesting capabilities. By controlling the mass ratio and frequency ratio, the first two resonances of primary mass can be tuned close to each other while maintaining comparable magnitudes. The 2DOF configuration is expected to be more adaptive and efficient than the conventional 1DOF structure, which could only operate near its sole resonance. The 2DOF EM-EH chip is fabricated on silicon-on-insulator (SOI) wafer through double-sided deep reactive-ion etching (DRIE). Induction coil is only patterned on the primary mass for energy conversion. With current prototype at an acceleration of 0.12 g, two resonances of 326 and 391 Hz with output voltages of 3.6 and 6.5 mV are obtained respectively, providing good validation for the modeling results. This paper offers new insights of implementing a multimodal MEMS EM-EH device.

An earthquake has three important characteristics; namely, amplitude, frequency content and duration. Amplitude and frequency content have a direct impact but not necessarily the sole cause of structural damage. Regarding the duration, some researchers show a high correlation between strong motion duration and structural damage whereas some others find no relation. This paper focuses on the ground motion durations characterized by Arias Intensity (AI). High duration may increase the damage state of structure for the damage accumulation. This paper investigates the response time histories (acceleration, velocity and displacement) of RC buildings under the different strong motion durations. Generally, eight earthquake records were selected from different soil type, and these records were grouped according to their PGA and frequency ranges. Maximum plastic rotation and drift response was chosen as damage indicator. In general, there was a positive correlation between strong motion duration and damage; however, in some PGA and frequency ranges input motions with shorter durations might cause more damage than the input motions with longer durations. In soft soils, input motions with longer durations caused more damage than the input motions with shorter durations.

The generation of betatron radiations by laser-accelerated electron beams is of great interest in the scientific community as it has many applications. In this paper, we propose a new method for the generation of short wavelength betatron radiations. In the new scheme, a high power laser pulse is sent into a capillary plasma waveguide at an off-axis position to intentionally enhance the betatron oscillation amplitude, which can lead to the production of shorter wavelength radiations. We demonstrated that the idea works by 2D particle-in-cell simulations and we also developed a theory to explain the phenomena. In this paper, details of the results are described.

Based on the fact that the electronic throttle angle effect performs well in the traditional car following model, this paper attempts to introduce the electronic throttle angle into the smart driver model (SDM) as an acceleration feedback control term, and establish an extended smart driver model considering electronic throttle angle changes with memory (ETSDM). In order to show the practicability of the extended model, the next generation simulation (NGSIM) data was used to calibrate and evaluate the extended model and the smart driver model. The calibration results show that, compared with SDM, the simulation value based on the ETSDM is better fitted with the measured data, that is, the extended model can describe the actual traffic situation more accurately. Then, the linear stability analysis of ETSDM was carried out theoretically, and the stability condition was derived. In addition, numerical simulations were explored to show the influence of the electronic throttle angle changes with memory and the driver sensitivity on the stability of traffic flow. The numerical results show that the feedback control term of electronic throttle angle changes with memory can enhance the stability of traffic flow, which shows the feasibility and superiority of the proposed model to a certain extent.

This paper presents a novel flocking algorithm based on a memory-enhanced disturbance observer. To compensate for external disturbances, a filtered regressor for the double integrator model subject to external disturbances is designed to extract the disturbance information. With the filtered regressor method, the algorithm has the advantage of eliminating the need for acceleration information, thus reducing the sensor requirements in applications. Using the information obtained from the filtered regressor, a batch of stored data is used to design an adaptive disturbance observer, ensuring that the estimated values of the parameters of the disturbance system equation and the initial value converge to their actual values. The result is that the flocking algorithm can compensate for external disturbances and drive agents to achieve the desired collective behavior, including virtual leader tracking, inter-distance keeping, and collision avoidance. Numerical simulations verify the effectiveness of the algorithm proposed in the present study.

We propose a new method to detect gravitational waves, based on spatial coherence interferometry with stellar light, as opposed to the conventional temporal coherence interferometry with laser sources. The proposed method detects gravitational waves by using two coherent beams of light from a single distant star measured at separate space-based detectors with a long baseline. This method can be applied to either the amplitude or intensity interferometry. This experiment allows for the search of gravitational waves in the lower frequency range of $10^{-6}$ to $10^{-4}$ Hz. In this work, we present the detection sensitivity of the proposed stellar interferometer by taking the detector response and shot and acceleration noises into account. Furthermore, the proposed experimental setup is capable of searching for primordial black holes and studying the size of the target neutron star, which are also discussed in the paper., 12 pages, 7 figures

As the current aspect, the nonstructural components (NSCs) linked with the structures are more affected during the seismic motion. It causes not only loss of the economy but also affected life. The various codal provision has been available for minimizing the damages of primary components, but for NSCs, a minimal requirement is functional. So that more investigation is required for understating the behavior of NSCs during the seismic motion. The research aims to understand the behavior of acceleration demand on NSCs in a building. Structures subjected to inertia forces due to earthquakes experience damage of nonstructural components (NSC). The inertia force acting the NSCs are related to acceleration amplification factor. For obtaining the peak horizontal floor acceleration with respect to tectonic ground motion, these factors are used. In this paper, mathematical models of the acceleration amplification factor defined as the peak floor acceleration with respect to peak ground acceleration, given by previous researchers, has been compared. For this 2,4,6,8 and 10 storey moment-resisting frame models considering 29 ground motion data ranging between 0.1g to 0.2g, is analyzed using linear time history method. The supports of the models are considered fixed. The ETABS software is used for the analysis of the models. To analyses the models, the modal mass participation ratio plays a significant role. ASCE 7-05 defines that the structure should be investigated and designed when the model mass participation ratio is equal to or more than 90 per cent. Based on the results, a comparison of the reported models is made. There is a strong need for further research to refine the models for the realistic prediction of acceleration amplification factor.

Acceleration sensor is usually used to test the performance of equipment under high-acceleration vibration. It is widely used in aero-engine, steam turbine and other equipment working in high-acceleration vibration environment. Calibration is an important means to ensure the accuracy and reliability of the measurement results of the acceleration sensor. Aiming at the conventional intermediate frequency (IF) calibration system using many instruments and complicated operation, this paper designs a resonant high-acceleration calibration system based resonant beam. The system amplifies the acceleration amplitude through the resonance of the resonant beam at the natural frequency, thereby generating high-acceleration values to calibrate the sensor. Then the vibration control algorithm of the calibration system is optimized, and the stability of the system is verified through experiments. Finally, the communication between the upper and lower computers is carried out in the vibration control system and the laser measurement system, and the metrological traceability is realized. The experimental results show that the system can effectively calibrate the sensitivity amplitude and phase of high-acceleration sensor in the frequency range of 100-2148 Hz and the acceleration range of 50-11853 m/s2. This calibration system is of great significance to the research on the calibration of IF acceleration sensor.

One of the goals in the SDGs that a region must achieve is 100% sanitation access. Sanitation is considered to have a significant impact on the quality of public health, both in rural and urban areas. The city of Bandung as a city with a high-density level has a big challenge in resolving sanitation matters. Acceleration efforts are needed to improve sanitation access in the city of Bandung which is still low so that it can realize open defecation free (ODF) for every urban village in the city of Bandung. This paper aims to provide a logical framework in the form of efforts that can be made to increase ODF in the city of Bandung. By collecting secondary data, interviews and FGDs as well as the highest and best use approach, the results show that the most important thing is to encourage the community to realize the need for a septic tank through community based total sanitation triggering (STBM) activities, connecting household wastewater channels to PDAM Sewerage, construction of small and large-scale communal septic tanks / IPAL and construction of “Gendong” pipelines, especially those in riverbank areas.

Due to the industrial development and the growing modernity, the elevator systems have become indispensable in many multi-story buildings. When electrical elevators are employed to transport people, riding comfort becomes a very important issue, especially when high-speed elevators are used in high-rise buildings. The elevator systems should provide a good stop accuracy and excellent levels of ride comfort. Passengers experience some problems that affect their comfort such as vibration and jerk that occur when travelling between elevator floors especially when starting and stopping the cabin. To minimize the effects of these problems, the cabin must be driven in such a way as to ensure smooth operation and smooth starting and stopping. Therefore, there is a need to control the voltage and frequency of the electric motor that drives the elevator cabin. This paper introduces a look at the different types of variable speed drives and how they’re used in electric elevator systems, discussing current systems as well as recent development in the field. Therefore, a variable-speed design that provides smooth movement is needed to include a smooth ride, accurate leveling, and a large number of start and stop operations First, some basic principles in driving systems, such as load curves and driving speed/torque, as well as their relationship to stability, are discussed; reference curve generation; speed curve profiling of the elevator system to achieve smooth transmission. The latest study in this topic reached the implementation of an elevator prototype driven by permanent magnet linear synchronous motor (PMSLM) loaded by 24kg. The motor was controlled by voltage frequency drive (VFD) programmed with offline S-curve to get a smooth start and smooth stop for the elevator cabin and constant travel speed with the least jerk possible, estimated by 88% compared the that without using the driver.

An economical and effective method to measure displacement is to integrate the acceleration signal. Because of the zero drift in the acceleration sensor, there will be a trend term in the process of acceleration secondary integration, which will cause some errors in displacement measurement. In this paper, several methods of acceleration signal processing with zero drift are given, and the advantages and disadvantages of these methods as well as the applicable occasions are analysed, which have important reference value for selecting reasonable methods in dealing with engineering problems.

The Fourier amplitude spectrum of acceleration will drop rapidly in the high frequency range. Anderson and Hough quantitatively studied the attenuation law of the acceleration Fourier spectrum above the corner frequency, and proposed the high-frequency attenuation parameter Kappa ( ) to describe this phenomenon. It has important applications in the field of engineering earthquakes, and is widely used by seismologists and engineers in the work of ground motion simulation and attenuation relations. Based on the Anderson method, this paper proposed a method of first smoothing the Fourier acceleration spectrum with a 0.4 Hz Parzen window and then fitting the solution value. The Fukushima earthquake data from Japan’s KiK-net seismic network on February 13, 2021 was used to verify the reliability of the method. The results showed that when the width of the Parzen window was set to 0.4 Hz, the calculation accuracy of the value was effectively improved.

In this paper, the asynchronous induction coil gun is selected as the object of study, and its working principle is firstly briefly introduced, then the mathematical model is established by using the knowledge of electromagnetism, and then the MAXWELL component of ANSYS analysis software is used to simulate the velocity change curve of the projectile in the time domain under different conditions by combining static analysis and transient analysis, which reveals the relationship between the armature The relationship between structural parameters such as armature material, armature axial length, armature position, armature inner diameter and armature outer diameter and projectile end velocity is revealed, and the influence of several structural parameters on the acceleration performance of coil gun launcher is summarized and analyzed, and the optimized design principles of armature are summarized according to the obtained conclusions to provide theoretical references for practical applications.

In conventional linear accelerators, the beam is accelerated with a synchronous harmonic of the radio frequency field where the electric field component is collinear with the beam direction. This approach requires the design of complex accelerating structures, especially for low-energy heavy ions. If the beam motion were sustainably coupled to transverse electromagnetic fields, this could significantly simplify the accelerating structure design, and even allow acceleration with free-space waves. However, despite the long history of the proposed concept for accelerating low-velocity ion beams, it has not found practical application, partially because of the complexity of the technical design. In this paper, we present a practical design approach for this undulator-based accelerator for low-energy heavy-ions, reminiscent of the inverse free electron laser operating principle, but in a different parameter space.

In traditional heavy truck design process, a large number of real vehicle tests are required to evaluate the ride comfort of the heavy truck. This not only increases the R&D costs but also prolongs the R&D cycle, which brings great inconvenience. This paper establishes a three-dimensional digital model in Adams/car based on the relevant parameters of a hybrid heavy truck. The ride comfort with different speeds was tested on B-level random roads and A-level impulsive roads, and the maximum body vibration acceleration of the heavy truck when driving on A-level impulse roads, weighted root mean square value of acceleration of driving seat vibration when driving on a B-level random road are obtained with different speeds. These values reflect the impact on human comfort and health when driving, provide a theoretical basis for the subsequent optimization design and greatly save manpower and material resources.

With the development of the industrial internet, the comprehensive application of big data, the internet of things and artificial intelligence are becoming quietly extensive, and they connect physical things to the digital world tightly. Being smart and intelligent has become one of the most important directions of future social development. As an agent, robots will be widely utilized in every corner of society, and the robot era has come quietly. This paper mainly studies how to let the robot walk according to the prescribed route as a person. Our innovation points are as follows: Firstly, compared with the traditional packaging robot, the steering gear of the legs is similar to that of normal people, and the hands, arms, and heads can also cooperate in the march, just like normal people. Tracking, individual turns, and special gestures can be achieved. Under the combined action of the threshold, CCD, sensor, and 12 steering gear, the robot can complete the patrol walk at a fast speed.

The process of gear shifting in vehicles automatic transmissions is considered in the paper as the shock interaction of transmission elements. Two mathematical models are proposed and considered for simulation the gear shifting processes. Computer simulation of the models’ movement during acceleration of a vehicle, as well as modes of low - and high-frequency gear shift cycling (self-oscillations of the output shaft of the gearbox) is carried out. Methods for decreasing the amplitude of the gearbox output shaft oscillations caused by the impact nature of gear shifting are proposed.

In this paper, it is shown that microparticles can be effectively neutralised in the (spatial) plasma afterglow of an inductively coupled plasma. A key element in the reported experiments is the utilisation of a grounded mesh grid separating the plasma bulk and the ‘shielded’ plasma afterglow. Once particles—being injected in and charged by the inductively coupled plasma—had passed this mesh grid, the plasma was switched off while the particles continued to be transported under the influence of both flow and gravity. In the shielded spatial plasma afterglow region, the particle charge was deducted from their acceleration in an externally applied electric field. Our experiments demonstrate that all particles were neutralised independently of the applied electric field magnitude. The achieved neutralisation is of primary importance for the further development of plasma-assisted contamination control strategies as well as for a wide range of other applications, such as colourimetric sensing, differential mobility analysers, and medical applications.

Objective Activity energy expenditure (EE) plays an important role in healthcare, therefore, accurate EE measures are required. Currently available reference EE acquisition methods, such as doubly labeled water and indirect calorimetry, are complex, expensive, uncomfortable, and/or difficult to apply on real time. To overcome these drawbacks, the goal of this paper is to propose a model for computing EE in real time (minute-by-minute) from heart rate and accelerometer signals. Approach The proposed model, which consists of an original branched model, uses heart rate signals for computing EE on moderate to vigorous physical activities and a linear combination of heart rate and counts per minute for computing EE on light to moderate physical activities. Model parameters were estimated from a given data set composed of 53 subjects performing 25 different physical activities (light-, moderate- and vigorous-intensity), and validated using leave-one-subject-out. A different database (semi-controlled in-city circuit), was used in order to validate the versatility of the proposed model. Comparisons are done versus linear and nonlinear models, which are also used for computing EE from accelerometer and/or HR signals. Main results The proposed piecewise model leads to more accurate EE estimations ([Formula: see text], [Formula: see text] and [Formula: see text] J kg-1 min-1 and [Formula: see text], [Formula: see text], and [Formula: see text] J kg-1 min-1 on each validation database). Significance This original approach, which is more conformable and less expensive than the reference methods, allows accurate EE estimations, in real time (minute-by-minute), during a large variety of physical activities. Therefore, this model may be used on applications such as computing the time that a given subject spent on light-intensity physical activities and on moderate to vigorous physical activities (binary classification accuracy of 0.8155).

With the development of laser technology, laser-driven proton acceleration provides a new method for proton tumor therapy. However, it has not been applied in practice because of the wide and decreasing energy spectrum of laser-accelerated proton beams. In this paper, we propose an analytical model to reconstruct the spread-out Bragg peak (SOBP) using laser-accelerated proton beams. Firstly, we present a modified weighting formula for protons of different energies. Secondly, a theoretical model for the reconstruction of SOBPs with laser-accelerated proton beams has been built. It can quickly calculate the number of laser shots needed for each energy interval of the laser-accelerated protons. Finally, we show the 2D reconstruction results of SOBPs for laser-accelerated proton beams and the ideal situation. The final results show that our analytical model can give an SOBP reconstruction scheme that can be used for actual tumor therapy.