scholarly journals Vacuum magnetic levitation transport: definition of optimal characteristics

2016 ◽  
Vol 2 (3) ◽  
pp. 18-35 ◽  
Author(s):  
V M Fomin ◽  
V I Zvegintsev ◽  
D J Nalivaichenko ◽  
Y A Terent’ev

Known to a wide circle of specialists of the transport, the concept of "Evacuated Тube Тransport Technology" (ET3) [1] is an energy efficient complex magnetic levitation, vacuum and superconducting technology for high-speed ground transportation. The concept is presented as the most effective solution to problem increase the speed and capacity of the transport system c is acceptable the cost of moving passengers and cargo, and low cost of energy. To determine the optimal ranges of working parameters of the considered transportation system the analysis of the characteristics of the rarefied environment. Based on considerations of balance of power the cost of maintaining the vacuum in the system and to overcome aerodynamic drag throughout the speed range of the vehicle (TC) (500÷6500 km/h) it is shown that the lower bound of the optimal depth of vacuum to the vacuum environment, for the vehicle to relatively low speeds, is 25÷80 PA. For vehicles with speeds close to the maximum I would like to have the pressure of 1 PA or less.

2021 ◽  
Vol 11 (9) ◽  
pp. 3934
Author(s):  
Federico Lluesma-Rodríguez ◽  
Temoatzin González ◽  
Sergio Hoyas

One of the most restrictive conditions in ground transportation at high speeds is aerodynamic drag. This is even more problematic when running inside a tunnel, where compressible phenomena such as wave propagation, shock waves, or flow blocking can happen. Considering Evacuated-Tube Trains (ETTs) or hyperloops, these effects appear during the whole route, as they always operate in a closed environment. Then, one of the concerns is the size of the tunnel, as it directly affects the cost of the infrastructure. When the tube size decreases with a constant section of the vehicle, the power consumption increases exponentially, as the Kantrowitz limit is surpassed. This can be mitigated when adding a compressor to the vehicle as a means of propulsion. The turbomachinery increases the pressure of part of the air faced by the vehicle, thus delaying the critical conditions on surrounding flow. With tunnels using a blockage ratio of 0.5 or higher, the reported reduction in the power consumption is 70%. Additionally, the induced pressure in front of the capsule became a negligible effect. The analysis of the flow shows that the compressor can remove the shock waves downstream and thus allows operation above the Kantrowitz limit. Actually, for a vehicle speed of 700 km/h, the case without a compressor reaches critical conditions at a blockage ratio of 0.18, which is a tunnel even smaller than those used for High-Speed Rails (0.23). When aerodynamic propulsion is used, sonic Mach numbers are reached above a blockage ratio of 0.5. A direct effect is that cases with turbomachinery can operate in tunnels with blockage ratios even 2.8 times higher than the non-compressor cases, enabling a considerable reduction in the size of the tunnel without affecting the performance. This work, after conducting bibliographic research, presents the geometry, mesh, and setup. Later, results for the flow without compressor are shown. Finally, it is discussed how the addition of the compressor improves the flow behavior and power consumption of the case.


Author(s):  
H. Hirani ◽  
P. Samanta

The present paper introduces a concept of hydrodynamic-permanent-magnetic hybrid bearing. The hybrid bearing uses repulsive force between permanent magnets and fluid force developed due to relative speed in a single assembly arrangement. Repulsive type passive magnetic levitation has advantage of minimum starting torque. Hydrodynamic lubrication mechanism has advantage of low friction at medium and high speed. This hybridization will be an attractive choice in commercial applications for its low cost, structural-simplicity and no metal-to-metal contact. An experimental setup is designed and developed to investigate the performance characteristics of proposed concept of hybrid bearing. Minimum film thickness, oil flow rate, and temperature rise are recorded at various speed- and load- conditions. Results are plotted to demonstrate the behavior of hybrid bearing arrangement.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Priyanka Kakria ◽  
N. K. Tripathi ◽  
Peerapong Kitipawang

Online telemedicine systems are useful due to the possibility of timely and efficient healthcare services. These systems are based on advanced wireless and wearable sensor technologies. The rapid growth in technology has remarkably enhanced the scope of remote health monitoring systems. In this paper, a real-time heart monitoring system is developed considering the cost, ease of application, accuracy, and data security. The system is conceptualized to provide an interface between the doctor and the patients for two-way communication. The main purpose of this study is to facilitate the remote cardiac patients in getting latest healthcare services which might not be possible otherwise due to low doctor-to-patient ratio. The developed monitoring system is then evaluated for 40 individuals (aged between 18 and 66 years) using wearable sensors while holding an Android device (i.e., smartphone under supervision of the experts). The performance analysis shows that the proposed system is reliable and helpful due to high speed. The analyses showed that the proposed system is convenient and reliable and ensures data security at low cost. In addition, the developed system is equipped to generate warning messages to the doctor and patient under critical circumstances.


2021 ◽  
Author(s):  
Tao Wang

Point-to-point parallel links are widly used in short-distance high-speed data communications. For these links, the design goal is not only to integrate a large number of I/Os in the systems, but also to increase the bit rate per I/O. The cost per I/O has to be kept low as performance improves. Voltage and timing error sources limit the performance of data links and affect its robustnest. These kinds of noise impose greater challenges in parallel data links, such as inter-signal timing skew and inter-signal cross-talk. The use of low-cost schemes, such as single-ended signaling, is effected signaficantly [sic] by the voltage and timging [sic] noise. Fully differential signaling schemes, two physical paths per signal channel, significantly increases the cost of system. Therefore, overcoming the voltage noise, keeping the cost low are two challenges in high-speed parallel links. In this thesis, we propose a new current-mode signaling scheme current-mode incremtnal [sic] signaling for high-speed parallel links. Also, the circuits of the receiver called current-integrating receiver are presented. To assess the effectiveness of the proposed signaling scheme, a 4-bit parallel link consisting of four bipolar current-mode drivers, five 10 cm microstrip lines with a FR4 substrate, and four proposed current-integrating receivers is implemented in UMC 0.13[micro]m, 1.2V CMOS technology and analyzed using SpectreRF from Cadence Design Systems with BSIM3V3 device models. Simulation results demonstrate that the proposed current-mode incremental signaling scheme and the current-integrating receiver are capable of transmitting parallel data at 2.5 Gbyte/s.


2022 ◽  
Author(s):  
Henry H. Hunter ◽  
Ukadike C. Ugbolue ◽  
Graeme G. Sorbie ◽  
Wing-Kai Lam ◽  
Fergal M. Grace ◽  
...  

Abstract The purpose of this study was to compare swing time and golf club angle parameters during golf swings using three, two dimensional (2D) low cost, Augmented-Video-based-Portable-Systems (AVPS) (Kinovea, SiliconCoach Pro, SiliconCoach Live). Twelve right-handed golfers performed three golf swings whilst being recorded by a high-speed 2D video camera. Footage was then analysed using AVPS-software and the results compared using both descriptive and inferential statistics. There were no significant differences for swing time and the golf phase measurements between the 2D and 3D software comparisons. In general, the results showed a high Intra class Correlation Coefficient (ICC > 0.929) and Cronbach’s Coefficient Alpha (CCA > 0.924) reliability for both the kinematic and temporal parameters. The inter-rater reliability test for the swing time and kinematic golf phase measurements on average were strong. Irrespective of the AVPS software investigated, the cost effective AVPS can produce reliable output measures that benefit golf analyses.


2020 ◽  
Vol 22 (Supplement_E) ◽  
pp. E110-E112
Author(s):  
Gian Piero Perna

Abstract Identifying patients at high risk of coronary events is the main focus of cardiovascular prevention. For primary prevention score and risk cards are very low cost solutions, but only of limited efficacy, thus justifying the use of non-invasive imaging testing for the purpose of increasing the ‘diagnostic gain’. Considering all the diagnostic tests employed, only few demonstrated significant additional contribution to the risk score stratification. Coronary imaging with high speed volumetric computed tomography can provide essential information in ruling out and/or definition of coronary artery disease but also has limitations as far as the biological risk, the costs, and the difficulties of putting into perspective the results obtained in asymptomatic patients.


Author(s):  
Daniel B. Hess ◽  
Brian D. Taylor ◽  
Allison C. Yoh

Bus rapid transit (BRT) is growing rapidly in popularity because it is viewed widely as an efficient and effective means to improve both transit service and patronage. This paper argues that two distinct views of BRT are emerging: ( a) BRT as a new form of high-speed, rubber-tired, rail-like rapid transit and ( b) BRT as a cost-effective way to upgrade both the quality and image of traditional fixed-route bus service. These two views carry different price tags because the cost of planning, constructing, and operating BRT depends on the complexity of new service features and on rises for BRT that offer service characteristics approaching those of light rail. This study fills a gap in the literature on the costs of BRT by examining in detail component costs–-actual costs for recently implemented services and projected costs for planned new services–-for a sample of BRT systems in North American cities. The study examined BRT costs of 14 planned and recently opened BRT systems to determine how the wide range of BRT service and technology configurations affect costs. The study found that although some of the most successful and popular new BRT systems are high-quality services operating in mixed traffic and implemented at relatively low cost, most BRT projects on the drawing boards are more elaborate, more expensive systems than many currently in service. Most new BRT projects emphasize elaborate LRT-type improvements to lines and stations in one or a few corridors rather than less splashy improvements (such as next-bus monitors, signal preemption, queue-jump lanes, and so forth) affecting more lines and modes in local transit networks. Among the 14 systems examined here, most could be characterized as light rail lite.


2011 ◽  
Vol 225-226 ◽  
pp. 589-592
Author(s):  
Yan Liu ◽  
Ze Gang Ye

The current Synchro-to-Digital conversion (S/DC)with high reliability, high accuracy and widely used in the military field, but it has high cost and low tracking speed, not suitable for high speed and low-cost industrial applications. In this work, the principle of synchro and the harmonics of the synchro output signals are investigated. Multifunction S/DC software design using FFT algorithm and IIR digital filter technology is proposed. It Integrated many functions, such as angle position, harmonics analysis and filter, it also improved measurement accuracy and speed, reduced the cost. The simulation results by Matlab show that the method is feasible.


2017 ◽  
Vol 3 (1) ◽  
pp. 47-57
Author(s):  
S A Kaznacheev ◽  
T S Zimenkova ◽  
A S Krasnov

Today, one of the most urgent tasks of modern transport systems in terms of volume growth and quality improvement, freight and passenger transportation worldwide, is to increase the speed of transportation and reduce the cost of energy resources associated with these transportations. These tasks can be solved by introducing high-speed, in particular magnetic-lev- el transport systems. In this paper, we describe and compare the variants of assemblies of magnetic poles based on the Halbach massif. The relevance of the studies carried out is confirmed by the world experience in the use of permanent magnets in the field of magneto-levitation technologies in various branches of science and technology. The purpose of the research and comparative analysis of variants of assemblies of magnetic poles based on the Halbach massif is to obtain data on the possibility of using such assembly variants in levitation systems of magnetic-leav- ing transport [7], as well as visual proof that mathematical modeling does not allow to fully describe emerging phenomena In this article, we use empirical methods of investigation. The results obtained will find their application in the design of the design, which will reduce both the mass-dimensions and the energy consumption of the levitation system. The practical significance of the studies obtained lies in the possibility of applying the principles considered practically in any magnetic-levitation transport systems. Conclusion: Based on the experimental studies, data were obtained on the levitation forces and the braking forces, which make it possible to draw conclusions about the advisability of using these assembly variants.


2021 ◽  
Author(s):  
Tao Wang

Point-to-point parallel links are widly used in short-distance high-speed data communications. For these links, the design goal is not only to integrate a large number of I/Os in the systems, but also to increase the bit rate per I/O. The cost per I/O has to be kept low as performance improves. Voltage and timing error sources limit the performance of data links and affect its robustnest. These kinds of noise impose greater challenges in parallel data links, such as inter-signal timing skew and inter-signal cross-talk. The use of low-cost schemes, such as single-ended signaling, is effected signaficantly [sic] by the voltage and timging [sic] noise. Fully differential signaling schemes, two physical paths per signal channel, significantly increases the cost of system. Therefore, overcoming the voltage noise, keeping the cost low are two challenges in high-speed parallel links. In this thesis, we propose a new current-mode signaling scheme current-mode incremtnal [sic] signaling for high-speed parallel links. Also, the circuits of the receiver called current-integrating receiver are presented. To assess the effectiveness of the proposed signaling scheme, a 4-bit parallel link consisting of four bipolar current-mode drivers, five 10 cm microstrip lines with a FR4 substrate, and four proposed current-integrating receivers is implemented in UMC 0.13[micro]m, 1.2V CMOS technology and analyzed using SpectreRF from Cadence Design Systems with BSIM3V3 device models. Simulation results demonstrate that the proposed current-mode incremental signaling scheme and the current-integrating receiver are capable of transmitting parallel data at 2.5 Gbyte/s.


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