scholarly journals ESTIMATION OF THE DISTANCE BETWEEN STATIONS OF OVERTAKING TRAINS WHEN ORGANIZING A MIXED HIGH-SPEED, PASSENGER AND FREIGHT TRAFFIC ON A RAILWAY LINE

2021 ◽  
pp. 5
Author(s):  
Y. B. WANG
Keyword(s):  
High Speed ◽  
Simulation Analysis ◽  
Maximum Speed ◽  
Railway Line ◽  
Freight Traffic ◽  
Optimal Distance ◽  
Shortest Distance ◽  
Different Types ◽  
Transportation Capacity ◽  
Transit Capacity

Purpose. This paper presents the calculation method and result of reasonable station spacing in the organization of mixed high-speed passenger and freight transportation, at different speed combinations and different types of train schedules. Methodology. By using the principle of the shortest distance between stations, this paper analyzes the possible layout of passenger and freight trains running at different speeds between Brest and Moscow, and work out the optimal distance between overtaking stations. According to the shortest distance between stations, the blocking method with four-digit automatic should be used when the maximum speed of the passenger train is 250 km/h. The crossing scheme for different types of trains is determined, and the train schedule period (TDS) of each scheme is determined. Calculate the appropriate distance between stations that had been passed through with different trip intervals according to the characteristics of the passing passenger and freight trains. By adopting simulation analysis, the influence of different number of trains and their composition on the station spacing is simulated to work out the reasonable railway station spacing for passenger and freight train with a speed of 250 km / h. Findings. In the case of passenger and freight traffic with the speed of 250 km / h, the optimal distance for stations between Brest and Moscow should be around 35 km. In order to make effective use of the existing infrastructure and achieve maximum transit capacity of the railway, it is recommended to increase the speed of the low priority trains. Originality. The distance between stations on a line will affect the number of stations on the entire line, as well as the maximum train speed and the number of train pairs. Excessive or insufficient station spacing will affect the transportation capacity and efficiency. Therefore, reasonable station spacing will determine the number of trains and the maximum speed of each train for both passenger and freight. Practical value. This paper proposes a method to estimate the reasonable spacing between crossing stations, which can ensure the effective utilization of the capacity of railway sections when high speed passenger trains on existing lines are running at speeds of up to 250 km/h.

scholarly journals A COMPARATIVE EARTHWORK AND COST ANALYSIS OF IMPROVING AN EXISTING RAILWAY LINE AND CONSTRUCTING A NEW HIGH-SPEED LINE IN TURKEY

2016 ◽  
Vol XLII-2/W1 ◽  
pp. 13-18
Author(s):  
K. A. Gumus ◽  
V. E. Gulal
Keyword(s):  
Cost Analysis ◽  
High Speed ◽  
Track Length ◽  
Engineering Structures ◽  
High Speed Railway ◽  
Total Cost ◽  
Railway Line ◽  
The Past ◽  
Ongoing Work ◽  
Different Types

In the past few decades, high-speed railways have become an important transportation system due to their high operational speed, and globally, the networks of these railways have been extended. In addition, there is ongoing work on the construction of new high-speed railways as well as improving existing lines to achieve the same operational speed. To contribute to high-speed railway works in Turkey, this study compared two high-speed railway lines; an existing conventional line, the design of which was improved, and a new high-speed line. The design of an existing conventional railway line was improved according to optimal geometric characteristics of high-speed railways and an alternative line was simulated. These two lines were evaluated on three different types of land in terms of the required volume of earthworks, engineering structures and total cost. The results show that the length of the conventional line was reduced after the improvement process; however, new engineering structures are needed. Furthermore, compared to the alternative line, the track length and total length of engineering structures required for the improvement of the existing line was shorter and the volume of required earthworks was less resulting in lower costs.

scholarly journals Multiview deep learning based on tensor decomposition and its application in fault detection of overhead contact systems

2021 ◽  
Author(s):  
Xuewu Zhang ◽  
Yansheng Gong ◽  
Chen Qiao ◽  
Wenfeng Jing
Keyword(s):  
High Speed ◽  
Tensor Decomposition ◽  
Detection Methods ◽  
Detection Accuracy ◽  
Feature Maps ◽  
Training Time ◽  
Detection Model ◽  
Railway Line ◽  
Result Show ◽  
Deep Layers

AbstractThis article mainly focuses on the most common types of high-speed railways malfunctions in overhead contact systems, namely, unstressed droppers, foreign-body invasions, and pole number-plate malfunctions, to establish a deep-network detection model. By fusing the feature maps of the shallow and deep layers in the pretraining network, global and local features of the malfunction area are combined to enhance the network's ability of identifying small objects. Further, in order to share the fully connected layers of the pretraining network and reduce the complexity of the model, Tucker tensor decomposition is used to extract features from the fused-feature map. The operation greatly reduces training time. Through the detection of images collected on the Lanxin railway line, experiments result show that the proposed multiview Faster R-CNN based on tensor decomposition had lower miss probability and higher detection accuracy for the three types faults. Compared with object-detection methods YOLOv3, SSD, and the original Faster R-CNN, the average miss probability of the improved Faster R-CNN model in this paper is decreased by 37.83%, 51.27%, and 43.79%, respectively, and average detection accuracy is increased by 3.6%, 9.75%, and 5.9%, respectively.

scholarly journals Does the Opening of High-Speed Railway Lines Reduce the Carbon Intensity of China’s Resource-Based Cities?

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4648
Author(s):  
Zhipeng Tang ◽  
Ziao Mei ◽  
Jialing Zou
Keyword(s):  
High Speed ◽  
National Average ◽  
Carbon Intensity ◽  
Time Varying ◽  
Low Carbon ◽  
High Speed Railway ◽  
Different Types ◽  
Endogenous Selection ◽  
Mode Of Development ◽  
The Impact

The carbon intensity of China’s resource-based cities (RBCs) is much higher than the national average due to their relatively intensive mode of development. Low carbon transformation of RBCs is an important way to achieve the goal of reaching the carbon emissions peak in 2030. Based on the panel data from 116 RBCs in China from 2003 to 2018, this study takes the opening of high-speed railway (HSR) lines as a quasi-experiment, using a time-varying difference-in-difference (DID) model to empirically evaluate the impact of an HSR line on reducing the carbon intensity of RBCs. The results show that the opening of an HSR line can reduce the carbon intensity of RBCs, and this was still true after considering the possibility of problems with endogenous selection bias and after applying the relevant robustness tests. The opening of an HSR line is found to have a significant reducing effect on the carbon intensity of different types of RBC, and the decline in the carbon intensity of coal-based cities is found to be the greatest. Promoting migration of RBCs with HSR lines is found to be an effective intermediary way of reducing their carbon intensity.

Dynamic Analysis of DVG 850 High-Speed Machining Center

2012 ◽  
Vol 487 ◽  
pp. 203-207
Author(s):  
Gong Xue Zhang ◽  
Xiao Kai Shen
Keyword(s):  
High Speed ◽  
Simulation Analysis ◽  
Response Analysis ◽  
Improved Method ◽  
Analysis Software ◽  
Element Analysis ◽  
Harmonic Response ◽  
Machining Center ◽  
Calculation Results ◽  
Harmonic Response Analysis

Purpose, with the application of workbench finite element analysis software, get the analysis results of DVG 850 high-speed vertical machining center via the modal analysis and harmonic response analysis. Use the calculation results for reference, put forward the improved method, and prove the credibility of the simulation analysis by testing DVG 850 prototype.

scholarly journals Study on the High-Speed Milling Performance of High-Volume Fraction SiCp/Al Composites

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4143
Author(s):  
Youzheng Cui ◽  
Shenrou Gao ◽  
Fengjuan Wang ◽  
Qingming Hu ◽  
Cheng Xu ◽  
...  
Keyword(s):  
High Speed ◽  
Large Scale ◽  
Volume Fraction ◽  
Simulation Analysis ◽  
Cutting Temperature ◽  
High Volume ◽  
Cutting Parameters ◽  
High Volume Fraction ◽  
High Wear Resistance ◽  
Element Analysis

Compared with other materials, high-volume fraction aluminum-based silicon carbide composites (hereinafter referred to as SiCp/Al) have many advantages, including high strength, small change in the expansion coefficient due to temperature, high wear resistance, high corrosion resistance, high fatigue resistance, low density, good dimensional stability, and thermal conductivity. SiCp/Al composites have been widely used in aerospace, ordnance, transportation service, precision instruments, and in many other fields. In this study, the ABAQUS/explicit large-scale finite element analysis platform was used to simulate the milling process of SiCp/Al composites. By changing the parameters of the tool angle, milling depth, and milling speed, the influence of these parameters on the cutting force, cutting temperature, cutting stress, and cutting chips was studied. Optimization of the parameters was based on the above change rules to obtain the best processing combination of parameters. Then, the causes of surface machining defects, such as deep pits, shallow pits, and bulges, were simulated and discussed. Finally, the best cutting parameters obtained through simulation analysis was the tool rake angle γ0 = 5°, tool clearance angle α0 = 5°, corner radius r = 0.4 mm, milling depth ap = 50 mm, and milling speed vc= 300 m/min. The optimal combination of milling parameters provides a theoretical basis for subsequent cutting.

Design of New Dual-Motor Independent Drive System for Electric Vehicle

2012 ◽  
Vol 591-593 ◽  
pp. 251-258
Author(s):  
Wen Wei Wang ◽  
Cheng Lin ◽  
Wan Ke Cao ◽  
Jiao Yang Chen
Keyword(s):  
Electric Vehicle ◽  
Network Architecture ◽  
High Speed ◽  
Simulation Analysis ◽  
Stability Control ◽  
Driving System ◽  
System A ◽  
Important Direction ◽  
Time Predictability ◽  
Information Scheduling

Multi-motor wheel independent driving technology is an important direction of electric vehicle(EV). Based on the analysis of the features of existing independent driving system of electric vehicle, a new dual-motor independent driving system configuration was designed. Complete parameters matching and simulation analysis of the system include motor, reducer, and battery. Distributed control network architecture based on high-speed CAN bus was developed, and information scheduling was optimized and real-time predictability was analyzed based on the rate monotonic (RM) algorithm and jitter margin index. The vehicle lateral stability control was achieved based on coordinated electro-hydraulic active braking. Based on the new dual-motor independent driving system, a new battery electric car was designed and tested. The results show that the vehicle has excellent dynamic and economic performance.

scholarly journals Specific Absolute Velocity Thresholds during Male Basketball Games Using Local Positional System; Differences between Age Categories

2021 ◽  
Vol 11 (10) ◽  
pp. 4390
Author(s):  
Carlos Sosa ◽  
Alberto Lorenzo ◽  
Juan Trapero ◽  
Carlos Ribas ◽  
Enrique Alonso ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Real Time ◽  
Effect Size ◽  
High Speed ◽  
Maximum Speed ◽  
Large Effect Size ◽  
Moderate Effect Size ◽  
Positional System ◽  
Moderate Effect ◽  
Distance Zone

The aim of this study was (I) to establish absolute specific velocity thresholds during basketball games using local positional system (LPS) and (II) to compare the speed profiles between various levels of competitions. The variables recorded were total distance (TD); meters per minute (m·min); real time (min); maximum speed (Km h−1), distance (m), percentage distance, and percentage duration invested in four speed zones (standing–walking; jogging; running; and high-speed running). Mean and standard deviation (±SD) were calculated, and a separate one-way analysis of variance was undertaken to identify differences between competitions. TD (3188.84 ± 808.37 m) is covered by standing–walking (43.51%), jogging (36.58%), running (14.68%), and sprinting (5.23%) activities. Overall, 75.22% of the time is invested standing–walking, jogging (18.43%), running (4.77%), and sprinting (1.89%). M·min (large effect size), % duration zone 2 (moderate effect size); distance zone 4 (large effect size), and % distance zone 4 (very large effect size) are significantly higher during junior than senior. However, % distance zone 1 (large effect size) and % duration zone 1 (large effect size) were largely higher during senior competition. The findings of this study reveal that most of the distance and play time is spent during walking and standing activities. In addition, the proportion of time spent at elevated intensities is higher during junior than in senior competition.

High-Speed End Milling Using a Feedforward Control Architecture

1996 ◽  
Vol 118 (2) ◽  
pp. 178-187 ◽  
Author(s):  
E. D. Tung ◽  
M. Tomizuka ◽  
Y. Urushisaki
Keyword(s):  
High Speed ◽  
Feedforward Control ◽  
End Milling ◽  
Phase Error ◽  
Cutting Speed ◽  
Frequency Domain Analysis ◽  
Maximum Speed ◽  
Drive Control ◽  
Machining Errors ◽  
Feedforward Controller

Experiments are performed for end milling aluminum at 15,000 RPM spindle speed (1,508 m/min cutting speed) and up to 3 m/min table feedrate using an experimental machine tool control system. A digital feedforward controller for feed drive control incorporates the Zero Phase Error Tracking Controller (ZPETC) and feedforward friction compensation. The controller achieves near-perfect (±3 μm) tracking over a 26 mm trajectory with a maximum speed of 2 m/min. The maximum contouring error for a 26 mm diameter circle at this speed is less than 4 μm. Tracking and contouring experiments are conducted for table feedrates as high as 10 m/min. Frequency domain analysis demonstrates that the feedforward controller achieves a bandwidth of 10 Hz without phase distortion. In a direct comparison of accuracy, the machining errors in specimens produced by the experimental controller were up to 20 times smaller than the errors in specimens machined by an industrial CNC.

Interface Features of the DDR SDRAM Memory Test Diagnostic Device

2021 ◽  
Vol 26 (3-4) ◽  
pp. 282-290
Author(s):  
S.V. Volobuev ◽  
◽  
V.G. Ryabtsev ◽  
Keyword(s):  
Data Transmission ◽  
High Speed ◽  
Maximum Speed ◽  
Diagnostic Device ◽  
Semiconductor Memory ◽  
Storage Devices ◽  
Memory Modules ◽  
Electronic Elements ◽  
Synchronization Scheme ◽  
Test Diagnostics

The I/О synchronization scheme plays an important role in achieving maximum speed and reliability of data transmission during memory operation. This paper presents the interface architecture of the DDR SDRAM test diagnostic device. It was demonstrated that the proposed interface components provide the formation of a bidirectional synchro signal for gating written and read data when performing test diagnostics of chips and DDR SDRAM memory devices. Compared to traditional methods, the proposed interface components were made on integrated electronic elements, which reduced the size and power consumption. It has been established that the use of a multiphase synchronization system to implement the interface eliminated the use of delay lines, the disadvantages of which are large dimensions and the complexity of changing the delay time. The interface components under consideration are intended for use in test diagnostics devices that have a multiprocessor structure, which increases the speed of forming test actions and reference reactions. The performed functional modeling and debugging of strobe signal generators confirmed the feasibility of the designs. The proposed interface of the test diagnostics device allows performing test diagnostics of modern high-speed chips and semiconductor memory modules at the operating frequency, which increases the reliability of the results obtained. Interface components can be used by manufacturers of test diagnostics tools for modern high-speed storage devices.

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