scholarly journals A Calculation Method for Vehicle Movement Reconstruction from Videos

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Hao Feng ◽  
Weiguo Shi ◽  
Feng Chen ◽  
Young-Ji Byon ◽  
Weiwei Heng ◽  
...  

This paper proposes a new enhanced method based on one-dimensional direct linear transformation for estimating vehicle movement states in video sequences. The proposed method utilizes a contoured structure of target vehicles, and the data collection procedure is found to be relatively stable and effective, providing a better applicability. The movements of vehicles in the video are captured by active calibration regions while the spatial consistency between the vehicle’s driving track and the calibration information are in sync. The vehicle movement states in the verification phase are estimated using the proposed method first, and then the estimated states are compared with the actual movement states recorded in the experimental test. The results show that, in the case of camera perspective of 90 degrees, in all driving states of low speed, high speed, or deceleration, the error between estimated speed and recorded speed is less than 1.5%, the error of accelerations is less than 7%, and the error of distances is less than 2%; similarly, in the case of camera perspective of 30 degrees, the errors of speeds, distances, and accelerations are less than 4%, 5%, and 10%, respectively. It is found that the proposed method is superior to other existing methods.

Author(s):  
Xintian Liu ◽  
Yang Qu ◽  
Xiaobing Yang ◽  
Yongfeng Shen

Background:: In the process of high-speed driving, the wheel hub is constantly subjected to the impact load from the ground. Therefore, it is important to estimate the fatigue life of the hub in the design and production process. Objective:: This paper introduces a method to study the fatigue life of car hub based on the road load collected from test site. Methods:: Based on interval analysis, the distribution characteristics of load spectrum are analyzed. The fatigue life estimation of one - dimensional and two - dimensional load spectra is compared by compiling load spectra. Results:: According to the S-N curve cluster and the one-dimensional program load spectrum, the estimated range fatigue life of the hub is 397,100 km to 529,700 km. For unsymmetrical cyclic loading, each level means and amplitude of load were obtained through the Goodman fatigue empirical formula, and then according to S-N curve clusters in the upper and lower curves and two-dimensional program load spectrum, estimates the fatigue life of wheel hub of the interval is 329900 km to 435200 km, than one-dimensional load spectrum fatigue life was reduced by 16.9% - 17.8%. Conclusion:: This paper lays a foundation for the prediction of fatigue life and the bench test of fatigue durability of auto parts subjected to complex and variable random loads. At the same time, the research method can also be used to estimate the fatigue life of other bearing parts or high-speed moving parts and assemblies.


2016 ◽  
Vol 74 (8) ◽  
pp. 632-637 ◽  
Author(s):  
Vernon Furtado da Silva ◽  
Mauricio Rocha Calomeni ◽  
Rodolfo Alkmim Moreira Nunes ◽  
Carlos Elias Pimentel ◽  
Gabriela Paes Martins ◽  
...  

ABSTRACT This study focused upon the functional capacity of mirror neurons in autistic children. 30 individuals, 10 carriers of the autistic syndrome (GCA), 10 with intellectual impairments (GDI), and 10 non-autistics (GCN) had registered eletroencephalogram from the brain area theoretically related to mirror neurons. Data collection procedure occurred prior to brain stimulation and after the stimulation session. During the second session, participants had to alternately process figures evoking neutral, happy, and/or sorrowful feelings. Results proved that, for all groups, the stimulation process in fact produced additional activation in the neural area under study. The level of activation was related to the format of emotional stimuli and the likelihood of boosting such stimuli. Since the increase of activation occurred in a model similar to the one observed for the control group, we may suggest that the difficulty people with autism have at expressing emotions is not due to nonexistence of mirror neurons.


2012 ◽  
Vol 155-156 ◽  
pp. 12-17 ◽  
Author(s):  
Lian Xu Wang ◽  
Da Wei Qu ◽  
Chang Qing Song ◽  
Ye Tian

To research the performance optimization of high speed car diesel engine,firstly according to the characteristic of car diesel engine with Variable Nozzle Turbocharger (VNT), one-dimensional cycle model of the engine was established by using simulation software BOOST and validated by experimental data in this paper. The turbine blades’ opening corresponding to different speed was determined. Therefore the problem that the VNT surges at low engine speed and the inlet air flow is insufficient at high speed was solved. Based on the above model, this paper improved the efficiency of the engine by optimizing the compression ratio and the distribution phase of camshaft and then used the experimental data to check the simulation results. Meanwhile the fuel consumption and the possibility of the engine operation roughness decreased.


Author(s):  
V. Vlasenko ◽  
A. Shiryaeva

New quasi-two-dimensional (2.5D) approach to description of three-dimensional (3D) flows in ducts is proposed. It generalizes quasi-one-dimensional (quasi-1D, 1.5D) theories. Calculations are performed in the (x; y) plane, but variable width of duct in the z direction is taken into account. Derivation of 2.5D approximation equations is given. Tests for verification of 2.5D calculations are proposed. Parametrical 2.5D calculations of flow with hydrogen combustion in an elliptical combustor of a high-speed aircraft, investigated within HEXAFLY-INT international project, are described. Optimal scheme of fuel injection is found and explained. For one regime, 2.5D and 3D calculations are compared. The new approach is recommended for use during preliminary design of combustion chambers.


Author(s):  
B. N. Cole ◽  
H. M. Bowers ◽  
F. R. Mobbs

A theory is presented for the high-speed, one-dimensional flow of a gas-solids mixture, assuming constant fractional lags of temperature and velocity between the solid particles and the gas. A mixture speed of sound is is derived and used as the basis of a mixture Mach number. Expressions are deduced which are parallel to many well-known relationships in orthodox one-dimensional gas dynamics. The investigation covers frictionless flow in a variable area duct and flow with friction in a constant area duct. The effect of solids volume is also taken into account.


VLSI Design ◽  
1998 ◽  
Vol 6 (1-4) ◽  
pp. 155-160
Author(s):  
A. M. Anile ◽  
O. Muscato ◽  
S. Rinaudo ◽  
P. Vergari

Recent advances in technology leads to increasing high speed performance of submicrometer electron devices by the scaling of both process and geometry. In order to aid the design of these devices it is necessary to utilize powerful numerical simulation tools. In an industrial environment the simulation codes based on the Drift-Diffusion models have been widely used. However the shrinking dimension of the devices causes the Drift-Diffusion based simulators to become less accurate. Then it is necessary to utilize more refined models (including higher order moments of the distribution function) in order to correctly predict the behaviour of these devices. Several hydrodynamical models have been considered as viable simulation tools. It is possible to discriminate among the several hydrodynamical models on the basis of their results on the output characteristics of the electron device which are measurable (I-V curves). We have analyzed two classes of hydrodynamical models: i) HFIELDS hydrodynamical models and HFIELDS drift-diffusion model; ii) self-consistent extended hydrodynamical models with relaxation times determined from Monte Carlo simulations.


2017 ◽  
Vol 27 (8) ◽  
pp. 984-1001 ◽  
Author(s):  
Nazan Çakirer Çalbayram ◽  
Sebahat Altundağ ◽  
Bahise Aydin

Hospitalized children can have various fantasies about hospital, health staff, and related tools and equipment. They need to develop new coping strategies for compliance with hospitalization.This study aimed to investigate the perception of nurses by children with acute and chronic illness through their drawings. The study was carried out using a descriptive research model. “Nurses through the eyes of sick children data collection form” was used in data collection procedure. The instruction “draw a picture of a nurse, please” was used to get the children to draw a picture. The majority of the children portrayed nurses as a smiling face. The children with chronic diseases featured nurses more in their drawings and they mentioned more nurse duties. The most important sign of the progression of nursing is that the mentioning of the modern roles of nursing by the children in their drawings and expressions. As children are influenced by their emotions, thoughts, observations, and experiences while drawing pictures, nurses can determine their thoughts about the disease, hospitals, physicians, and nurses by having sick children draw pictures.


1947 ◽  
Vol 14 (4) ◽  
pp. A317-A336 ◽  
Author(s):  
Ascher H. Shapiro ◽  
W. R. Hawthorne

Abstract Recent developments in the fields of propulsion, flow machinery, and high-speed flight have emphasized the need for an improved understanding of the characteristics of compressible flow. A one-dimensional analysis for flow without shocks is presented which takes into account the simultaneous effects of area change, wall friction, drag of internal bodies, external heat exchange, chemical reaction, change of phase, injection of gases, and changes in molecular weight and specific heat. The method of selecting independent and dependent variables, and the organization of the working equations, leads, it is believed, to a better understanding of the influence of the foregoing effects, and also simplifies greatly the analytical treatment of particular problems. Examples are given first of several simple types of flow, including (a) area change only; (b) heat transfer only; (c) wall friction only; and (d) gas injection only. In addition, examples of flow with combined effects are given, including (a) simultaneous friction and area change; (b) simultaneous friction and heat transfer; and (c) simultaneous liquid injection and evaporation. A one-dimensional analysis for flow through a discontinuity is presented, allowing for energy, shock, drag, and gas-injection effects, and for changes in gas properties. This analysis is applicable to such processes as: (a) the adiabatic normal shock; (b) combustion; (c) moisture condensation shocks; and (d) steady explosion waves.


Author(s):  
Ahmet Cihat Kapçık ◽  
Ali Öztüfekçi ◽  
Aybüke Demet Ören ◽  
Ayten Kaplan ◽  
Çiğdem Yılmaz Uzunkaya ◽  
...  

The increasing number of non-native English speakers in the world has led to the use of varieties of English. Nowadays, the number of speakers of English in the expanding circle has exceeded the number of speakers in the outer and inner circles. This has given rise to the scrutiny of English as a Lingua Franca (ELF). With this regard, the research on World Englishes (WEs) has increased over the last few decades. In light of these observations, the purpose of this chapter is to raise awareness of World Englishes (WEs) among preparatory students at private universities in Turkey. Specifically, the study is concerned with mentoring preparatory students through Wes-integrated courses. The participants of this study were 20 preparatory students at A2-level English proficiency. As data collection procedure, the mentor teacher of the existing program adapted EFL materials including videos, dialogues, and integrated four language skills. The data were collected through questionnaires and reflective essays. With regard to the results, the students had an idea about the concept of Wes, and they became aware of the varieties of English to some extent; specifically, they displayed consciousness about the status of English across the world and sympathy toward WEs.


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