Дисертації з теми "HIGH SPEED TRACK"

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1

Michas, Georgios. "Slab track systems for high-speed railways." Thesis, KTH, Väg- och banteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-96507.

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Анотація:
In the last 40 years an increase in train speed and axle load around the world and other challenges in the conventional ballasted track system gave birth to ballastless railway track system. This study examines in depth the various slab track systems that are being used today. Their design characteristics as well as the various requirements for efficient use are thoroughly explained. At least 34 different ballastless systems have been recorded in many railway networks throughout the world. The most significant slab track systems are analysed in detail and compared. Slab track designs have significant advantages comparing to ballasted tracks. The most significant are the high stability of the track, the almost non-existent need for maintenance, the long life cycle (60 years) and the reduced weight and height of the track. Their disadvantages against the ballasted tracks are mainly summarized in their higher construction costs. The Finite Element package ABAQUS/CAE is used to model a 3-D slab track design under static traffic loading. The results suggest that slab tracks have profoundly better stability and durability comparing to ballasted tracks mainly due to their higher stiffness and strength. The author underlines the need for further studies to undoubtedly prove the claimed advantages of slab track systems as well as to improve the costs associated with construction.
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2

Fesharaki, Mohammad. "3-D Dynamic Analysis of High-Speed Railroad Track." FIU Digital Commons, 2017. http://digitalcommons.fiu.edu/etd/3366.

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Анотація:
High-Speed Rail (HSR) as a fast, reliable and environmentally friendly mode of transportation has received a lot of attention in recent decades. The International Union of Railways reported that there are more than 18600 miles of HSR in operation and about 1.6 billion passengers per year are carried by them. Although there are plans for HSR in many states including Florida, the United States, however, is still hesitant to develop its own HSR network. One of the main barriers to developing high-speed rail is excessive vibration propagation to the media which may cause annoyance to people who live in the track neighborhood. Train induced vibration also contributes to track settlement, developing track flaws, and increasing life cycle cost of track and supporting structures. The aim of this research is to address this problem by conducting a comprehensive investigation into track dynamics. For this purpose, three-dimensional mass-spring-damper models of vehicle, track and supporting structures were developed and matrices of mass, stiffness, and damping of each subsystem were formed. The response of the whole system was, then, determined by coupling the subsystems using Hertz contact theory. The differential equations of the coupled system were solved by the Newmark integration method and the results including vertical and lateral displacements and forces were presented in the time domain. Since the purpose of this dissertation is to quantify the effect of track and vehicle condition on vibration level, rail defects were also taken into account and rail random irregularities for the vertical profile, Gauge, alignment and cross level (super elevation) were incorporated into a numerical solution. The results of the study show the effect of track and vehicle parameters on the response of the vehicle, track, and substructures. Since Florida and some other states in the United States are very prone to hurricanes, an investigation was conducted into the effect of wind speed on vehicle stability. For this purpose, a curved beam was modeled to consider the influence of track curvature, cant deficiency, wind speed and train speed simultaneously. The results from the study show the maximum allowable values of train speed and axle load for different wind speeds. The findings can be used to decide under what circumstances there is a risk of vehicle overturning and how to avoid it.
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3

Sárik, Veronika. "Decision-making model for track system of high-speed rail lines : Ballasted track, ballastless track or both?" Thesis, KTH, Byggvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-226308.

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Анотація:
During the 50 years of existence of high speed railways, the track structure solutions have developed both in number and in type. As of today, in case of conventional railway, there are 2 main types one could mention: ballasted and ballastless track solutions. However, there is no standardized procedure for choosing between these systems and between their respective variants, the decision is made on a case-by-case basis. This thesis aims to create a generic framework for decision making, primarily taking into account technical details. The model, the input parameters and variables can be easily adjusted and customized based on national standards, practices or other considerations, but the primary focus in the thesis have been the current Swedish regulations. The thesis has an overview on the influencing factors and attempts to include the most crucial ones of these into a decision-making model. This model compares 3 alternatives, namely the ballastless alternative, the ballasted alternative and the alternating system option, in which case the track system selection happens based on local factors, such as geotechnical conditions. These are considered and evaluated through Fuzzy logic, which supports the system selection affected by various sources of uncertainty. The decision is finally made through an LCC calculation. In order to handle the great uncertainties in the data used in the LCC, a Monte Carlo simulation is performed. The main added value of the thesis is considered to be the methodology for choosing the systems based on life-cycle cost after careful technical evaluation. This approach might provide basis for decision for track systems of high speed rail lines.
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4

Karis, Tomas. "Track Irregularities for High-Speed Trains : Evaluation of their correlation with vehicle response." Thesis, KTH, Järnvägsteknik, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-156640.

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5

Shimatake, Masao. "A track maintenance model for high-speed rail : a systems dynamics approach." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/43385.

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Анотація:
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 1997.
Vita.
Includes bibliographical references (leaves 174-175).
by Masao Shimatake.
M.S.
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6

Mohlén, Marcus, Jesper Malmberg, and Filip Hahrs. "Dimensioning of slabs for high-speed railway lines." Thesis, Linnéuniversitetet, Institutionen för byggteknik (BY), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-54091.

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The Swedish Transport Administration has been giving the task to set up a new standard for concrete slabs for the new high-speed railway in Sweden. They are demanding that the concrete slabs must be dimensioned according to the German Beton Kalender 2000. This report will explore the results when dimensioning a slab track, according to the German Beton Kalender 2000. Moment capacity, deformation, and crack width are calculated according to two structural theories, namely slab and beam theory, and a comparison between the two methods is presented.
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7

Leung, Joseph, Michio Aoyagi, Donald Billings, Herbert Hoy, Mei Lin, and Fred Shigemoto. "A MOBILE RANGE SYSTEM TO TRACK TELEMETRY FROM A HIGH-SPEED INSTRUMENTATION PACKAGE." International Foundation for Telemetering, 1998. http://hdl.handle.net/10150/607380.

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Анотація:
International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California
As renewal interest in building vehicles based on hypersonic technologies begin to emerge again, test ranges anticipating in supporting flight research of these vehicles will face a set of engineering problems. Most fundamentals of these will be to track and gather error free telemetry from the vehicles in flight. The first series of vehicles will likely be reduced-scale models that restrict the locations and geometric shapes of the telemetry antennas. High kinetic heating will further limit antenna design and construction. Consequently, antennas radiation patterns will be sub-optimal, showing lower gains and detrimental nulls. A mobile system designed to address the technical issues above will be described. The use of antenna arrays, spatial diversity and a hybrid tracking system using optical and electronic techniques to obtain error free telemetry in the present of multipath will be presented. System tests results will also be presented.
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8

Scoughton, Troy E., and Robert Danford. "A HIGH DATA RATE TELEMETRY PROCESSING SYSTEM FOR THE HIGH SPEED TEST TRACK AT HOLLOMAN AFB." International Foundation for Telemetering, 1990. http://hdl.handle.net/10150/613480.

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Анотація:
International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, Nevada
The system covered in this paper is the Telemetry Processing System (TPS) designed and installed for processing data acquired from high speed test sleds at Holloman AFB, NM. Because this facility operates as a test range, testing sleds from many different agencies for a variety of different purposes, prior knowledge is not always available concerning the instrumentation on the test sled to be used and therefore the type of data retrieval and processing required. The TPS must then be capable of acquiring and processing multiple data types including PAM and PDM, multiple FM streams (72 channels) and high speed PCM (4 channels) . Additionally, the requirement has been imposed for 3.2 Msample/sec analog-to-digital conversion capability for high resolution measurement of certain analog data (10 channels). When the above data are multiplexed with three time sources, eight channels of sled positional information and operated at maximum rate, the raw data exceed 15 Mbytes/sec. Depending on the scheme used to tag the samples, time stamp the data, and convert the data to engineering units, the processed data rate could have exceeded 100 Mbytes/sec and therefore the reasonable limit of existing telemetry processing technology. The TPS requires not only the capability to acquire and record this very high rate data, but also the realtime display of selected measurements. Further, the acquired data must be readily available immediately after the test for quick look evaluation, and for data selection for archival storage. This paper will explore the design process that allows the system to meet these requirements using mostly off-the-shelf or only slightly modified equipment by making clever compromises and effective use of stream separation. The paper will explore the hardware and software considerations which were examined and the solutions implemented in the final design. Development and integration of this system are currently underway, with delivery scheduled for later this year.
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9

Lia, Anne Margrethe. "Life Cycle Assessment of Technical Solutions for High-Speed Rail: Tunnel and Track designs." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18706.

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Анотація:
On the 19th of February 2010, the Ministry of Transport and Communication presented the Norwegian National Rail Administration with the task of assessing different aspects of the future of high-speed rail in Norway. The report, the Norwegian High-Speed Rail Assessment (NHSRA), consist three separate evaluations where the climate assessment by Bergsdal et al. (2012), motivated this thesis. Results from the report identify the railway infrastructure as the dominant emission source for the corridor, with the length of tunnels representing the determining factor. Simultaneously, an ongoing debate is comparing the safety and performance of track and tunnel technologies traditionally used in Norway to that of foreign tunnelling technology such as the drill and blast method which apply a full cast (European method), and a double shielded tunnel boring machine (TBM). The newest development in track technology is the slab track, which is now evaluated for tunnels and bridges in Norway (Jernbaneverket 2011). This thesis contributes to the ongoing debate concerning the construction of infrastructure for high-speed rail in Norway, by emphasizing the environmental impact of several relevant technologies and geological conditions. The assessment includes an evaluation of the impact of different tunnelling and track technologies, calculated for operation speeds of both 250km/h and 330km/h. Further, the environmental impact of different levels of support work and grout is assessed. In addition, this thesis includes a sensitivity analysis of the impact of service life for railway components. The assessment is calculated for two functional units: one meter tunnel and tunnel track, and for the case corridor, the potential high-speed rail corridor between Oslo-Stavanger, estimated for 250km/h obtained from the NHSRA by Bergsdal et al. (2012).Our results from this assessment account for the use of cement, steel and copper as the environmentally most important materials. Among the railway components, the tunnel lining and grout constitute the highest emission level of the case corridor. The different technical alternatives are compared against the technologies traditionally applied in Norway, and an average level of support work, which represents the baseline results of this thesis. Our results indicate that the double shielded tunnel-boring machine is the technology that contributes to the highest increase of emission level compared to baseline. Further, the variables that hold the greatest potential of reducing total emission level is the installation of slab track in tunnels and bridges, and level of grout in the tunnel construction.
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10

Rashid, Shahbaz. "Parametric study of bridge response to high speed trains, ballasted track on concrete bridges." Thesis, KTH, Bro- och stålbyggnad, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-99385.

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Анотація:
When a train enters a bridge, passenger sitting inside will feel a sudden bump in the track, which not only affect the riding comfort of the passengers but also put a dynamic impact on the bridge structure. Due to this impact force, we have very serious maintenance problems in the track close to the bridge structure. This sudden bump is produced when train travelling on the track suddenly hit by a very stiff medium like bridge structure. In order to reduce this effect, transition zones are introduced before the bridge so that the change in stiffness will occur gradually without producing any bump.   This master thesis examine the effect of track stiffness on the bridge dynamic response under different train speeds from 150 to 350 km/h with interval 5 km/h and also estimate the minimum length of transition zones require to reduce the effect of change in stiffness on the bridge. Study also gives us some guidelines about the choice of loading model of the train, location of maximum vertical acceleration, effect of ballast model on the results and minimum length of transition zone needs to include in the bridge-track FE-model, for dynamic analysis of the concrete bridges. To carry out this research MATLAB is used to produce an input file for the ABAQUS FEM program. ABAQUS will first read this file, model the bridge and then analysis the bridge. MATLAB will again read the result file, process the result data and plot the necessary graphs.   The Swedish X2000 train is used for this study, which has been modeled with two different methods: moving load model and sprung mass model, in order to see the difference in results. For verification of the MATLAB-ABAQUS model, a 42m long bridge is analysed and results are compared with known results. In this study, concrete simply supported bridges with spans of 5, 10, 15, 20, 25 m have been analysed.
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11

Stridfelt, Arvid. "High Speed On-Chip Measurment Circuit." Thesis, Linköping University, Department of Electrical Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2764.

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This master thesis describes a design exploration of a circuit capable of measuring high speed signals without adding significant capacitive load to the measuring node.

It is designed in a 0.13 CMOS process with a supply voltage of 1.2 Volt. The circuit is a master and slave, track-and-hold architecture incorporated with a capacitive voltage divider and a NMOS source follower as input buffer to protect the measuring node and increase the input voltage range.

This thesis presents the implementation process and the theory needed to understand the design decisions and consideration throughout the design. The results are based on transistor level simulations performed in Cadence Spectre.

The results show that it is possible to observe the analog behaviour of a high speed signal by down converting it to a lower frequency that can be brought off-chip. The trade off between capacitive load added to the measuring node and input bandwidth of the measurment circuit is also presented.

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12

Thomas, Jossian, and Barenys Assís Arañó. "Evaluation of 3D dynamic effects induced by high-speed trains on double-track slab bridges." Thesis, KTH, Bro- och stålbyggnad, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-188850.

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Анотація:
In addition to a static design, a dynamic analysis has to be performed for bridges for which the maximum permissible train speed exceeds 200 km/h. This analysis requires a lot of computing time, for this reason Svedholm and Andersson (2016) have developed a simple tool describing the relationship between the first eigenfrequency of the bridge, the span length and the minimum mass to fulfill the regulation specified in EN-1990. However, these diagrams are based on 2D beam models in which the 3D dynamic effects are not considered. An evaluation of the torsional modes has been performed by analyzing parametrized 3D bridge models, in order to obtain design diagrams including these effects. To do so, a frequency domain analysis has been implemented, based on a steadystate step previously performed in a FEM software. This approach provides a fast way to solve the equation of motion due to the Fourier transform properties, and allows applying several load configurations which are convenient for a parametric study. From this analysis it can be concluded that the thickness to fulfill the demands is larger for 3D models than for 2D. On one hand, contribution of torsional modes of vibration is more significant for the shortest span length, and on the other hand shear-lag effects lead to a reduction of the total resisting bending section.
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13

Sayeed, Md Abu. "Design of ballasted railway track foundations using numerical modelling with special reference to high speed trains." Thesis, Curtin University, 2016. http://hdl.handle.net/20.500.11937/796.

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Анотація:
A new design method for ballasted railway track foundations was developed based on improved empirical models and sophisticated three-dimensional finite element numerical analyses. The method was developed in the form of simple design charts for use by practitioners. The results obtained from the method were found to be in an excellent agreement with the field observations, and the method is expected to provide a significant contribution to the current railway tack design code of practice.
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14

Younis, Choudhry Jabbar. "Design and Implementation of a high-efficiency low-power analog-to-digital converter for high-speed transceivers." Thesis, Linköpings universitet, Elektroniksystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-77178.

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Анотація:
Modern communication systems require higher data rates which have increased thedemand for high speed transceivers. For a system to work efficiently, all blocks ofthat system should be fast. It can be seen that analog interfaces are the main bottleneckin whole system in terms of speed and power. This fact has led researchersto develop high speed analog to digital converters (ADCs) with low power consumption.Among all the ADCs, flash ADC is the best choice for faster data conversion becauseof its parallel structure. This thesis work describes the design of such a highspeed and low power flash ADC for analog front end (AFE) of a transceiver. Ahigh speed highly linear track and hold (TnH) circuit is needed in front of ADCwhich gives a stable signal at the input of ADC for accurate conversion. Twodifferent track and hold architectures are implemented, one is bootstrap TnH andother is switched source follower TnH. Simulations show that high speed with highlinearity can be achieved from bootstrap TnH circuit which is selected for the ADCdesign.Averaging technique is employed in the preamplifier array of ADC to reduce thestatic offsets of preamplifiers. The averaging technique can be made more efficientby using the smaller number of amplifiers. This can be done by using the interpolationtechnique which reduces the number of amplifiers at the input of ADC. Thereduced number of amplifiers is also advantageous for getting higher bandwidthsince the input capacitance at the first stage of preamplifier array is reduced.The flash ADC is designed and implemented in 150 nm CMOS technology for thesampling rate of 1.6 GSamples/sec. The bootstrap TnH consumes power of 27.95mW from a 1.8 V supply and achieves the signal to noise and distortion ratio(SNDR) of 37.38 dB for an input signal frequency of 195.3 MHz. The ADC withideal TnH and comparator consumes power of 78.2 mW and achieves 4.8 effectivenumber of bits (ENOB).
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15

Orvnäs, Anneli. "Active Lateral Secondary Suspension in a High-Speed Train to Improve Ride Comfort." Licentiate thesis, KTH, Aeronautical and Vehicle Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10432.

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Анотація:

Active secondary suspension in trains has been studied for a number of years, showing promising improvements in ride comfort. However, due to relatively high implementation and maintenance costs, active technology is not being used in service operation to a large extent. The objective of this study is to develop an active lateral secondary suspension concept that offers good ride comfort improvements and enables centring of the carbody above the bogies when negotiating curves at unbalanced speed. Simultaneously, the active suspension concept should be a cost-effective solution for future series production. The thesis consists of an introductory part and three appended papers.

The introductory part describes the concept of active secondary suspension together with different actuator types and control methods. Further, the present simulation model and applied comfort evaluation methods are presented. The introductory part also comprises a summary of the appended papers, an evaluation of track forces and suggestions for further work.

Paper A presents the initial development of an active lateral secondary suspension concept based on sky-hook damping in order to improve vehicle dynamic performance, particularly on straight tracks. Furthermore, a Hold-Off-Device (HOD) function has been included in the suspension concept in order to centre the carbody above the bogies in curves and hence avoid bumpstop contact. Preparatory simulations as well as the subsequent on-track tests in the summer of 2007 showed that the active suspension provides improved passenger ride comfort and has significant potential to be a cost-effective solution for future implementation.

In Paper B, measurement results from on-track tests performed in 2008 are presented. The active secondary suspension concept was slightly modified compared to the one presented in the first paper. One modification was the implementation of a gyroscope in order to enable detection of transition curves and to switch off the dynamic damping in these sections. Ride comfort in the actively suspended carbody was significantly improved compared to that in the passively suspended car. The satisfactory results led to implementation of the active suspension system in long-term tests in service operation in the beginning of 2009.

In Paper C, a quarter-car model in MATLAB has been used to investigate a more advanced control algorithm: H instead of sky-hook. H control provides more flexibility in the design process due to the possibility to control several parameters. In particular, this is done by applying weight functions to selected signals in the system. When comparing the two control strategies through simulations, the results show that H control generates similar carbody accelerations at the same control force as sky-hook; however, the relative displacement displacement is somewhat lower.

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16

Gillet, Guillaume. "Simply supported composite railway bridge: a comparison of ballasted and ballastless track alternatives : Case of the Banafjäl Bridge." Thesis, KTH, Bro- och stålbyggnad, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-36359.

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17

Lestoille, Nicolas. "Stochastic model of high-speed train dynamics for the prediction of long-time evolution of the track irregularities." Thesis, Paris Est, 2015. http://www.theses.fr/2015PEST1094/document.

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Анотація:
Les voies ferrées sont de plus en plus sollicitées: le nombre de trains à grande vitesse, leur vitesse et leur charge ne cessent d'augmenter, ce qui contribue à la formation de défauts de géométrie sur la voie. En retour, ces défauts de géométrie influencent la réponse dynamique du train et dégradent les conditions de confort. Pour garantir de bonnes conditions de confort, les entreprises ferroviaires réalisent des opérations de maintenance de la voie, qui sont très coûteuses. Ces entreprises ont donc intérêt à prévoir l'évolution temporelle des défauts de géométrie de la voie pour anticiper les opérations de maintenance, et ainsi réduire les coûts de maintenance et améliorer les conditions de transport. Dans cette thèse, on analyse l'évolution temporelle d'une portion de voie par un indicateur vectoriel sur la dynamique du train. Pour la portion de voie choisie, on construit un modèle stochastique local des défauts de géométrie de la voie à partir d'un modèle global des défauts de géométrie et de big data de défauts mesurés par un train de mesure. Ce modèle stochastique local prend en compte la variabilité des défauts de géométrie de la voie et permet de générer des réalisations des défauts pour chaque temps de mesure. Après avoir validé le modèle numérique de la dynamique du train, les réponses dynamiques du train sur la portion de voie mesurée sont simulées numériquement en utilisant le modèle stochastique local des défauts de géométrie. Un indicateur dynamique, vectoriel et aléatoire, est introduit pour caractériser la réponse dynamique du train sur la portion de voie. Cet indicateur dynamique est construit de manière à prendre en compte les incertitudes de modèle dans le modèle numérique de la dynamique du train. Pour identifier le modèle stochastique des défauts de géométrie et pour caractériser les incertitudes de modèle, des méthodes stochastiques avancées, comme par exemple la décomposition en chaos polynomial ou le maximum de vraisemblance multidimensionnel, sont appliquées à des champs aléatoires non gaussiens et non stationnaires. Enfin, un modèle stochastique de prédiction est proposé pour prédire les quantités statistiques de l'indicateur dynamique, ce qui permet d'anticiper le besoin en maintenance. Ce modèle est construit en utilisant les résultats de la simulation de la dynamique du train et consiste à utiliser un modèle non stationnaire de type filtre de Kalman avec une condition initiale non gaussienne
Railways tracks are subjected to more and more constraints, because the number of high-speed trains using the high-speed lines, the trains speed, and the trains load keep increasing. These solicitations contribute to produce track irregularities. In return, track irregularities influence the train dynamic responses, inducing degradation of the comfort. To guarantee good conditions of comfort in the train, railways companies perform maintenance operations of the track, which are very costly. Consequently, there is a great interest for the railways companies to predict the long-time evolution of the track irregularities for a given track portion, in order to be able to anticipate the start off of the maintenance operations, and therefore to reduce the maintenance costs and to improve the running conditions. In this thesis, the long-time evolution of a given track portion is analyzed through a vector-valued indicator on the train dynamics. For this given track portion, a local stochastic model of the track irregularities is constructed using a global stochastic model of the track irregularities and using big data made up of experimental measurements of the track irregularities performed by a measuring train. This local stochastic model takes into account the variability of the track irregularities and allows for generating realizations of the track irregularities at each long time. After validating the computational model of the train dynamics, the train dynamic responses on the measured track portion are numerically simulated using the local stochastic model of the track irregularities. A vector-valued random dynamic indicator is defined to characterize the train dynamic responses on the given track portion. This dynamic indicator is constructed such that it takes into account the model uncertainties in the train dynamics computational model. For the identification of the track irregularities stochastic model and the characterization of the model uncertainties, advanced stochastic methods such as the polynomial chaos expansion and the multivariate maximum likelihood are applied to non-Gaussian and non-stationary random fields. Finally, a stochastic predictive model is proposed for predicting the statistical quantities of the random dynamic indicator, which allows for anticipating the need for track maintenance. This modeling is constructed using the results of the train dynamics simulation and consists in using a non-stationary Kalman-filter type model with a non-Gaussian initial condition. The proposed model is validated using experimental data for the French railways network for the high-speed trains
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18

Li, Xiangtao. "High-speed analog-to-digital conversion in SiGe HBT technology." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/24652.

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Анотація:
Thesis (Ph.D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008.
Committee Chair: Cressler, John D.; Committee Member: Laskar, Joy; Committee Member: Lee, Chin-Hui; Committee Member: Morley, Thomas; Committee Member: Papapolymerou, John
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19

Black, Brian C., Laura H. Bollock, Sinene Bouabid, Michael A. Glova, Jason A. Hall, Glynn M. Harden, Curtis J. Hickle, et al. "Sea TENTACLE: Track, Engage, & Neutralize Threats - Asymmetric & Conventional - in the Littoral Environment." Thesis, Monterey, California : U.S. Naval Postgraduate School, 2006. http://hdl.handle.net/10945/7275.

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Анотація:
Includes supplementary material.
Sea TENTACLE is a proposed afloat platform whose primary mission is to utilize the state-of-the-art technology of unmanned vehicles to monitor and neutralize all subsurface enemy threats in the littorals. This mission can be specified further as anti-submarine warfare, mine warfare and maritime surveillance. The design philosophy of Sea TENTACLE embodies the ideal of providing a multi-mission capable sea frame extending network-centric warfare into the littorals. The design goals of the TSSE team were first to develop a platform to deploy, recover, and maintain unmanned vehicle (e.g. UUVs, USVs, UAVs) and second to enableto ship to act as an afloat network operations center for distributed assets. Allowing all units to work together seamlessly to conduct focused missions in the littorals makes the Sea TENTACLE a creitical component within the network-centric environment. The versatility of its cargo hold and modular design allows Sea TENTACLE to be outfitted dynamically to complete a veriety of secondary missions including humanitarian aid, salvage and spacial operations support. Sea TENTACLE's combat management and operations system will employ the Enterprise architecture design enabling C4ISR capabilities that will meet emerging network centric warfare needs.
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20

Pasciak, Alexander Samuel. "The development of a high speed solution for the evaluation of track structure Monte Carlo electron transport problems using field programmable gate arrays." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2558.

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21

Perrin, Guillaume. "Random fields and associated statistical inverse problems for uncertainty quantification : application to railway track geometries for high-speed trains dynamical responses and risk assessment." Phd thesis, Université Paris-Est, 2013. http://pastel.archives-ouvertes.fr/pastel-01001045.

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Анотація:
Les nouvelles attentes vis-à-vis des nouveaux trains à grande vitesse sont nombreuses: on les voudrait plus rapides, plus confortables, plus stables, tout en étant moins consommateur d'énergie, moins agressif vis-à-vis des voies, moins bruyants... Afin d'optimiser la conception de ces trains du futur, il est alors nécessaire de pouvoir se baser sur une connaissance précise de l'ensemble des conditions de circulations qu'ils sont susceptibles de rencontrer au cours de leur cycle de vie. Afin de relever ces défis, la simulation a un très grand rôle à jouer. Pour que la simulation puisse être utilisée dans des perspectives de conception, de certification et d'optimisation de la maintenance, elle doit alors être tout à fait représentative de l'ensemble des comportements physiques mis en jeu. Le modèle du train, du contact entre les roues et le rail, doivent ainsi être validés avec attention, et les simulations doivent être lancées sur des ensembles d'excitations qui sont réalistes et représentatifs de ces défauts de géométrie. En ce qui concerne la dynamique, la géométrie de la voie, et plus particulièrement les défauts de géométrie, représentent une des principales sources d'excitation du train, qui est un système mécanique fortement non linéaire. A partir de mesures de la géométrie d'un réseau ferroviaire, un paramétrage complet de la géométrie de la voie et de sa variabilité semblent alors nécessaires, afin d'analyser au mieux le lien entre la réponse dynamique du train et les propriétés physiques et statistiques de la géométrie de la voie. Dans ce contexte, une approche pertinente pour modéliser cette géométrie de la voie, est de la considérer comme un champ aléatoire multivarié, dont les propriétés sont a priori inconnues. En raison des interactions spécifiques entre le train et la voie, il s'avère que ce champ aléatoire n'est ni Gaussien ni stationnaire. Ce travail de thèse s'est alors particulièrement concentré sur le développement de méthodes numériques permettant l'identification en inverse, à partir de mesures expérimentales, de champs aléatoires non Gaussiens et non stationnaires. Le comportement du train étant très non linéaire, ainsi que très sensible vis-à-vis de la géométrie de la voie, la caractérisation du champ aléatoire correspondant aux défauts de géométrie doit être extrêmement fine, tant du point de vue fréquentiel que statistique. La dimension des espaces statistiques considérés est alors très importante. De ce fait, une attention toute particulière a été portée dans ces travaux aux méthodes de réduction statistique, ainsi qu'aux méthodes pouvant être généralisées à la très grande dimension. Une fois la variabilité de la géométrie de la voie caractérisée à partir de données expérimentales, elle doit ensuite être propagée au sein du modèle numérique ferroviaire. A cette fin, les propriétés mécaniques d'un modèle numérique de train à grande vitesse ont été identifiées à partir de mesures expérimentales. La réponse dynamique stochastique de ce train, soumis à un très grand nombre de conditions de circulation réalistes et représentatives générées à partir du modèle stochastique de la voie ferrée, a été ainsi évaluée. Enfin, afin d'illustrer les possibilités apportées par un tel couplage entre la variabilité de la géométrie de la voie et la réponse dynamique du train, ce travail de thèse aborde trois applications
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22

Serrano, González Irene. "LCC approach for High-speed ballastless tracks." Thesis, KTH, Transportplanering, ekonomi och teknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-191159.

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Анотація:
An approach of life cycle cost analysis (LCCA) for high-speed ballastless tracks in Spain is carried out in this document based on an approximation of the present value behaviour through the Electre II Multi criteria method. A review of other LCC researches has been done analysing their results in order to adapt previous experimental tracks costs to the present study which is focused on construction and maintenance costs in Spain. Even though several ballastless systems are introduced and analysed in terms of costs, and environmental impacts; only four of them are deeply compared with ballasted tracks: Japanese Shinkansen, Rheda 2000, EDILON embedded rail system and LVT. The comparisons are established using ratios (ballastless/ballasted track costs) instead of total costs due to their lack of validation among countries and years. Furthermore, two case studies have been presented: one using 3% as discount rate which favours ballastless choice and another using 6% which in contrast, favours the traditional option. Last chapter aims to compare results from the presented method with proper present value calculations during 60 years in the Ballasted Madrid-Seville line (Spain).
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23

Forsgren, Niklas. "Sampling Ocsilloscope On-Chip." Thesis, Linköping University, Department of Electrical Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1563.

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Анотація:

Signal-integrity degradation from such factors as supply and substrate noise and cross talk between interconnects restricts the performance advances in Very Large Scale Integration (VLSI). To avoid this and to keep the signal-integrity, accurate measurements of the on-chip signal must be performed to get an insight in how the physical phenomenon affects the signals.

High-speed digital signals can be taken off chip, through buffers that add delay. Propagating a signal through buffers restores the signal, which can be good if only information is wanted. But if the waveform is of importance, or if an analog signal should be measured the restoration is unwanted. Analog buffers can be used but they are limited to some hundred MHz. Even if the high-speed signal is taken off chip, the bandwidth of on-chip signals is getting very high, making the use of an external oscilloscope impossible for reliable measurement. Therefore other alternatives must be used.

In this work, an on-chip measuring circuit is designed, which makes use of the principle of a sampling oscilloscope. Only one sample is taken each period, resulting in an output frequency much lower than the input frequency. A slower signal is easier to take off-chip and it can easily be processed with an ordinary oscilloscope.

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24

Merelle, Vincent. "Concept de radars novateurs pour la vision à travers les milieux opaques." Thesis, La Rochelle, 2018. http://www.theses.fr/2018LAROS017/document.

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Анотація:
La « vision » à travers les milieux opaques (murs, cloisons, décombres, ou plus généralement tout milieu qui occulte la vision humaine) est l’un des problèmes clefs du contrôle et de la sécurité. Il apparaît à l’heure actuelle un réel besoin de disposer de dispositifs d’observation à travers ces milieux pour des applications tant militaires (lors des assauts, des prises d’otages, etc.) que civiles (recherche de personnes enfouies dans des décombres, dans un incendie, etc). Les avancées sur cette problématique ont conduit à mettre en place des systèmes radars à très courte portée, opérationnels pour la détection et le tracking de personnes dans des environnements simples. Cependant ils nécessitent que les cibles soient en déplacement afin de les différencier des objets statiques. Cette limitation constitue un défaut majeur pour un certain nombre de scénarii réels où des personnes, par stratégie ou par contrainte, restent immobiles. Ces travaux de thèse visent à explorer les mécanismes de détection de personnes statiques par le biais de leurs micro-mouvements, e.g. des mouvements induits par le thorax lors de la respiration. Nous avons étudié - d’un point de vue théorique - les principes physiques sous-jacents à la détection de ces micro-mouvements par radar UWB impulsionnel à partir du mécanisme Doppler impulsionnel. Ce dernier s’appuie sur des mesures consécutives des phases des impulsions réfléchies. La compréhension de ce phénomène a permis de définir une architecture radar impulsionnelle et de la positionner, en termes de contributions, au regard des différents radars UWB proposés dans la littérature : le FMCW et le radar de bruit. Deux dispositifs radars ont servi de support à ce travail. Le premier, de type démonstrateur académique, repose sur l’utilisation d’un oscilloscope rapide pour numériser les impulsions UWB de 3 à 6 GHz de bande. Il a permis de mettre en place une chaîne de traitement complète de vision à travers les murs. Le second dispositif est un prototype radar développé autour d’une plateforme de numérisation ultra-rapide (100 Gsps par échantillonnage équivalent) de fréquence de rafraîchissement très élevée (100 Hz). Il est construit autour d’un FPGA, d’un ADC rapide (1,25 GHz) et d’un T&H très large bande (18 GHz). Il permet ainsi la détection des micro-mouvements par traitement Doppler impulsionnel
"Vision" through opaque environments (walls, partitions, rubble, or any environment that obscures human vision) is one of the key issues of control and security. Advances on this issue have led to operational shortrange radar systems for people detection and tracking in simple environments. However, most of them require the targets to move in order to differentiate them from static objects. This requirement constitues a major shortcoming for a certain number of real scenarios where people, by strategies or by constraints, remain motionless. Hence, this thesis aims to explore the mechanisms of detection of static people through their micro-movements, e.g. movements induced by the thorax during breathing. We have studied - from a theoretical point of view - the physical principles underlying the detection of these micro-movements by pulsed UWB radar with the pulsed Doppler phenomenon, which relies on consecutive measurements of the reflected pulses phases. The understanding of this phenomenon made it possible to define a radar architecture and to position it, in terms of contributions, with regard to the different UWB radars proposed in the literature : the FMCW and the noise radar. Two radar devices served as support for this work. An academic demonstrator based on the use of a fast oscilloscope to digitize the pulses. It allowed to set up a complete processing chain for the application of vision through the walls. The second device is a radar prototype developed around a high-speed scanning platform (100 Gsps perequivalent sampling) with a very high refresh rate (100 Hz). This prototype is built around an FPGA, a fast ADC (1.25 GHz) and a very wide band T&H (18 GHz). This thereby enables to detect micro-movements by pulsed Doppler processing
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25

Gry, Laurent. "Modélisation du comportement dynamique d'une voie TGV pour la réduction du bruit de roulement." Châtenay-Malabry, Ecole centrale de Paris, 1995. http://www.theses.fr/1995ECAP0419.

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Анотація:
Un modèle de voie périodique a été développé afin de réduire le bruit émis dans l'environnement durant le passage d'un train. Ce modèle, prenant en compte les déformations de la section du rail, couvre une large gamme de fréquences, 0 - 5000 Hz. La considération d'un appui discret le rend cependant moins performant dans les hautes fréquences, pour lesquelles les ondes propagatives émises sur une travée ont une longueur d'onde proche de la longueur d'appui. Une méthode générale d'analyse des milieux périodiques unidimensionnels est alors proposée afin de prendre en compte l'effet de la longueur d'appui
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26

Буряковський, Сергій Геннадійович. "Наукові основи вибору електроприводів стрілочних переводів для швидкісних та високошвидкісних залізниць". Thesis, Український державний университет залізничного транспорту, 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/29744.

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Анотація:
Дисертація на здобуття наукового ступеня доктора технічних наук за спеціальністю 05.22.09 – "Електротранспорт". Національний технічний університет "Харківський політехнічний інститут", Харків, 2017. Дисертація присвячена створенню теоретичних основ вибору та оцінки типу електроприводів стрілочних переводів, що працюють в оптимальних режимах з урахуванням нелінійностей навантаження та електрофізичних властивостей двигунів, на основі рішення задачі мінімізації основних показників якості як: час переводу, величина імпульсу удару гостряка об рамну рейку, величина пружної сили в робочій тязі, а також величина загальних втрат в системі. Запропоновано узагальнений векторний критерій ефективності роботи електроприводу стрілочного переводу, компонентами якого є час переводу, величини імпульсу удару гостряка, пружної сили, а також загальних втрат потужності системи за яким проведено оцінку придатності використання конкретного типу переводу для ділянок швидкісного та високошвидкісного руху. Розглянуто існуючі кінематичні схеми з типовими двигунами, а також запропоновано використати перспективну – шпальну компоновку з новими типами електродвигунів ротаційного та лінійного виду. Розроблено математичні моделі для існуючих та перспективних типів стрілочних переводів на базі двигунів ротативного і лінійного типів, що основані на рішенні рівняння Лагранжа для електромеханічної системи з урахуванням нелінійності магнітної системи. Створені імітаційні моделі електроприводів стрілочних переводів в середовищі MATLAB SIMULINK на базі двигуна постійного струму (ДПС), асинхронного двигуна (АД), вентильно-індукторного двигуна (ВІД), лінійного двигуна електромагнітного типу (ЛДЕМТ) і лінійного індуктор-ного двигуна (ЛІД) та проведена перевірка адекватності існуючим зразкам. Сформульовано задачу аналізу з визначення раціональної структури електроприводу стрілочного переводу на основі ДПС, АД, ВІД, ЛДЕМТ і ЛІД.
Doctoral thesis, technical sciences, specialty 05.22.09 – "Electric transport." National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2017. The dissertation is dedicated to develop of theoretical bases for the selection and evaluation of the types of electric drives of turnouts operating in optimal modes, taking into account the nonlinearities of the load and the electrophysical properties of the engines, on the basis of solving the problem of minimizing the main quality indicators such as: the transfer time , the value of the impulse of switch rail impact against a rail, the value of the elastic force in the working draft and the magnitude of the total losses in the system. The universal vector criterion for the working efficiency of the electric drive of turnouts is proposed. Its components are the transfer time, the value of the impulse of switch rail impact against a rail, the value of the elastic force in the working draft and the magnitude of the total losses in the system. The assessment of the appropriateness of application a specific type of turnouts for rapid and high-speed traffic segments is made. The kinematic schemes in the form of two- and three-mass electromechanical systems with standard engines are considered. Various control systems for the operated electric drives, which provide higher quality indicators for rapidity of the switching process of the switch rails, positioning accuracy and the impact force on the rail, are proposed. The railway sleeper layout of the turnout with new types of electric motors is suggested to applying. The mathematical models for existing and prospective types of turnouts based on motors of rotational and linear types, which based on the solution of the Lagrange equation for electromechanical system taking into account the nonlinearity of the magnetic system, have been developed. The simulation models of electric drives of turnouts in the software environment of MATLAB SIMULINK on the basis of a DC motor, an asynchronous motor, a valve-inductor motor, a linear motor of electromagnetic type and a linear inductor motor are developed. The adequacy verification on physical models was made. The problem of analysis for determining the rational structure of the electric drive of turnout based on DC motor, asynchronous motor, valve-inductor motor, linear motor of electromagnetic type and linear inductor motor is formulated.
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27

Буряковський, Сергій Геннадійович. "Наукові основи вибору електроприводів стрілочних переводів для швидкісних та високошвидкісних залізниць". Thesis, НТУ "ХПІ", 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/29739.

Повний текст джерела
Анотація:
Дисертація на здобуття наукового ступеня доктора технічних наук за спеціальністю 05.22.09 – "Електротранспорт". Національний технічний університет "Харківський політехнічний інститут", Харків, 2017. Дисертація присвячена створенню теоретичних основ вибору та оцінки типу електроприводів стрілочних переводів, що працюють в оптимальних режимах з урахуванням нелінійностей навантаження та електрофізичних властивостей двигунів, на основі рішення задачі мінімізації основних показників якості як: час переводу, величина імпульсу удару гостряка об рамну рейку, величина пружної сили в робочій тязі, а також величина загальних втрат в системі. Запропоновано узагальнений векторний критерій ефективності роботи електроприводу стрілочного переводу, компонентами якого є час переводу, величини імпульсу удару гостряка, пружної сили, а також загальних втрат потужності системи за яким проведено оцінку придатності використання конкретного типу переводу для ділянок швидкісного та високошвидкісного руху. Розглянуто існуючі кінематичні схеми з типовими двигунами, а також запропоновано використати перспективну – шпальну компоновку з новими типами електродвигунів ротаційного та лінійного виду. Розроблено математичні моделі для існуючих та перспективних типів стрілочних переводів на базі двигунів ротативного і лінійного типів, що основані на рішенні рівняння Лагранжа для електромеханічної системи з урахуванням нелінійності магнітної системи. Створені імітаційні моделі електроприводів стрілочних переводів в середовищі MATLAB SIMULINK на базі двигуна постійного струму (ДПС), асинхронного двигуна (АД), вентильно-індукторного двигуна (ВІД), лінійного двигуна електромагнітного типу (ЛДЕМТ) і лінійного індуктор-ного двигуна (ЛІД) та проведена перевірка адекватності існуючим зразкам. Сформульовано задачу аналізу з визначення раціональної структури електроприводу стрілочного переводу на основі ДПС, АД, ВІД, ЛДЕМТ і ЛІД.
Doctoral thesis, technical sciences, specialty 05.22.09 – "Electric transport." National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2017. The dissertation is dedicated to develop of theoretical bases for the selection and evaluation of the types of electric drives of turnouts operating in optimal modes, taking into account the nonlinearities of the load and the electrophysical properties of the engines, on the basis of solving the problem of minimizing the main quality indicators such as: the transfer time , the value of the impulse of switch rail impact against a rail, the value of the elastic force in the working draft and the magnitude of the total losses in the system. The universal vector criterion for the working efficiency of the electric drive of turnouts is proposed. Its components are the transfer time, the value of the impulse of switch rail impact against a rail, the value of the elastic force in the working draft and the magnitude of the total losses in the system. The assessment of the appropriateness of application a specific type of turnouts for rapid and high-speed traffic segments is made. The kinematic schemes in the form of two- and three-mass electromechanical systems with standard engines are considered. Various control systems for the operated electric drives, which provide higher quality indicators for rapidity of the switching process of the switch rails, positioning accuracy and the impact force on the rail, are proposed. The railway sleeper layout of the turnout with new types of electric motors is suggested to applying. The mathematical models for existing and prospective types of turnouts based on motors of rotational and linear types, which based on the solution of the Lagrange equation for electromechanical system taking into account the nonlinearity of the magnetic system, have been developed. The simulation models of electric drives of turnouts in the software environment of MATLAB SIMULINK on the basis of a DC motor, an asynchronous motor, a valve-inductor motor, a linear motor of electromagnetic type and a linear inductor motor are developed. The adequacy verification on physical models was made. The problem of analysis for determining the rational structure of the electric drive of turnout based on DC motor, asynchronous motor, valve-inductor motor, linear motor of electromagnetic type and linear inductor motor is formulated.
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28

CARRERA, DANNY HERNAN ZAMBRANO. "DETERMINATION OF THE TRAJECTORY OF HIGH SPEED GROUND VEHICLES IN PREDEFINED TRACKS THROUGH OPTIMIZATION TECHNIQUES." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2006. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=9352@1.

Повний текст джерела
Анотація:
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
Em veículos de competição com velocidades elevadas, o principal objetivo é chegar em primeiro lugar, o que significa percorrer um determinado número de voltas em uma trajetória fechada fazendo algumas manobras para cumprir o circuito no menor tempo possível, dentro das limitações impostas pelas caracteristicas dinâmicas e de condução destes veículos. A otimização é uma metodologia que pode ser usada para reproduzir trajetórias e técnicas de condução usadas pelos pilotos de corrida, e também para investigar os efeitos de vários parâmetros nas condições limites da estabilidade veicular. Neste trabalho, inicialmente é apresentado o desenvolvimento de um modelo dinâmico do veículo considerando as caracterítiscas suficientes para análise da trajetória, influenciada por parâmetros geométricos e físicos pertinentes. Em seguida é definido o problema de obtenção da trajetória empregando procedimentos de otimização, de modo a determinar como um veículo irá percorrer um traçado, considerando como função objetivo o tempo de percurso, que deverá ser mínimo, e tendo como restrições as condições dinâmicas do veículo e geométricas da pista, implementando rotinas que são usadas em conjunto com os algoritmos existentes na Optimization Toolbox do Matlab. Finalmente apresenta-se o comportamento do veículo, representado pelo modelo desenvolvido anteriormente em uma malha de controle de trajetória, de modo a comparar o comportamento assim obtido com aquele previsto pelo procedimento de otimização.
High speed competition vehicles are required to cover a determined number of laps in a closed trajectory circuit in a time that is the least possible, in the limits of the governing dynamic and driving characteristics of these vehicles. Optimization is a methodology that can be used in order to simulate trajectories and driving techniques of used by the competition pilots and to investigate the effects of several parameters in limit conditions of car stability. In this work it is first presented the development of the vehicle model considering the sufficient characteristics for trajectory analysis, influenced by pertinent geometric and physical parameters. In continuation, the problem of the optimal trajectory is defined using optimization procedures, in order to determine how a vehicle will follow the path, considering as an objective function the time to follow it, that must be the minimum, and having as constraints the vehicle dynamic conditions and the path geometry, implementing routines that are used with the Matlab´s Optimization Toolbox. Finally the behavior of the vehicle is presented, represented by the model developed previously in a trajectory control loop, in such a way to compare the resulting behavior with the one predicted by the optimization procedure.
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29

Liu, Kaiyi. "Characterization and Control of an Electrospinning Process." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1355239985.

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30

Гусак, Марина Анатоліївна, Марина Анатолиевна Гусак та Marina A. Gusak. "Підвищення ефективності роботи залізничної колії РїСЂРё спеціалізації напрямків для вантажних С– пасажирських перевезень". Thesis, Видавництво Дніпропетровського національного університету залізничного транспорту імені академіка Р’. Лазаряна, 2012. http://eadnurt.diit.edu.ua:82/jspui/handle/123456789/1349.

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Анотація:
Гусак, Рњ. Рђ. Підвищення ефективності роботи залізничної колії РїСЂРё спеціалізації напрямків для вантажних С– пасажирських перевезень : авт. РґРёСЃ. Рє. С‚. РЅ.: 05.22.06 / Рњ. Рђ. Гусак ; Дніпропетр. нац. СѓРЅ-С‚ залізн. трансп. С–Рј. акад. Р’. Лазаряна. - Р”. : Р’РёРґ-РІРѕ Днiпропетр. нац. СѓРЅ-ту залізн. трансп. iРј. акад. Р’. Лазаряна, 2012. УДК 625.1:656.222.1 ГРНТР? 73.29.11 Захист - 27 РіСЂСѓРґРЅСЏ 2012 СЂ.
UK: АНОТАЦІЯ Дисертація присвячена розробці методу формування раціональної схеми оволодіння перевезеннями для паралельних залізничних напрямків при впрова-дженні на одному з них швидкісного руху пасажирських поїздів, дослідженню особливостей і підвищенню ефективності роботи залізничної колії у разі пере-розподілу вантажопотоків між паралельними залізничними напрямками з ви-значенням параметрів плану лінії. Для порівняння варіантів вирішення задачі розмежування вантажного й пасажирського руху був використаний новий критерій, який ґрунтується на за-стосуванні комплексного показника роботи сил взаємодії колії і рухомого скла-ду, що дає можливість оцінювати знос колійної інфраструктури від потоку по-їздів за тривалий час експлуатації залізниці. Запропоновано метод раціонального розподілу поїздопотоків між парале-льними ходами, що дає можливість обґрунтовано обирати найбільш придатний варіант за декількома критеріями одночасно і дозволяє вирішувати поставлені Укрзалізницею завдання, зменшивши при цьому витрати на реконструкцію, пробіг поїздів і утримання колії. Отримані наукові результати, запропоновані методи досліджень та кла-сифікація напрямків можуть бути використані для розробки рекомендацій з пі-двищення пропускної й провізної спроможності напрямків, економічної оцінки впливу інтенсивності вантажного та пасажирського руху на знос інфраструкту-ри залізничного транспорту, уніфікації маси та довжини поїздів на основних напрямках залізниць України
RU: РђРќРќРћРўРђР¦Р?РЇ Диссертация посвящена разработке метода формирования рациональной схемы овладения перевозками для параллельных железнодорожных линий РїСЂРё организации РЅР° РѕРґРЅРѕР№ РёР· РЅРёС… скоростного движения поездов, исследованию особенностей Рё повышению эффективности работы железнодорожного пути РїСЂРё перераспределении грузопотоков между параллельными железнодорожны-РјРё направлениями СЃ определением параметров плана линии. Анализ основных направлений международных транспортных РєРѕСЂРёРґРѕСЂРѕРІ, которые РїСЂРѕС…РѕРґСЏС‚ через территорию Украины, показал, что без отделения пас-сажирского движения РѕС‚ РіСЂСѓР·РѕРІРѕРіРѕ Рё переустройства плана линии выполнить европейские требования, прежде всего РІ РІРѕРїСЂРѕСЃРµ реализации максимальной скорости движения, затруднительно. РџСЂРё перераспределении поездопотоков необходимо учитывать техниче-СЃРєРѕРµ состояние РѕР±РѕРёС… параллельных направлений. Для этого была разработана математическая модель совместного формирования рациональной схемы этап-РЅРѕРіРѕ овладения перевозками для параллельных железнодорожных линий РїСЂРё введении РЅР° РѕРґРЅРѕР№ РёР· РЅРёС… скоростного движения. Данная модель позволяет СЂРµ-шать задачи повышения скорости пассажирских поездов РїСЂРё минимальных эксплуатационных расходах Рё рациональных капитальных вложениях РЅР° пере-устройство линии. Р’ работе предложен новый критерий для сравнения вариантов решения задачи разделения РіСЂСѓР·РѕРІРѕРіРѕ Рё пассажирского движения, основанный РЅР° РїСЂРё-менении комплексного показателя работы СЃРёР» взаимодействия пути Рё РїРѕРґРІРёР¶-РЅРѕРіРѕ состава, который дает возможность оценивать РёР·РЅРѕСЃ путевой инфраструк-туры РѕС‚ потока поездов Р·Р° продолжительное время эксплуатации железной РґРѕ-СЂРѕРіРё. Переключение движения грузовых Рё пассажирских поездов РЅР° парал-лельные направления позволяет получить дополнительную прибыль Р·Р° счет уменьшения расстройства пути. Так, РЅР° участках, исключительно СЃ пассажир-СЃРєРёРј движением поездов прогнозируется увеличение межремонтных СЃСЂРѕРєРѕРІ РІ 2…2,5 раза. Для определения экономической оценки воздействия интенсивности РіСЂСѓ-Р·РѕРІРѕРіРѕ Рё пассажирского движения РЅР° РёР·РЅРѕСЃ путевой инфраструктуры Рё распре-деления расходов РЅР° содержание пути РІ зависимости РѕС‚ структуры поездопото-РєР° была применена вышеизложенная методика Рё разработана программа расче-тов Znosinfra. Уточнена Рё детализирована классификация направлений железных РґРѕСЂРѕРі РїРѕ категориям поездов Рё структуре поездопотока. Предложено четыре РІРёРґР° РЅР°-правлений: чисто пассажирское, преимущественно пассажирское, совмещен-РЅРѕРµ, РіСЂСѓР·РѕРІРѕРµ движение Рё соответствующие классификации графики распреде-ления скоростей движения поездов разных категорий. Получила дальнейшее развитие методика вероятностного моделирования потока поездов, РЅР° РѕСЃРЅРѕРІРµ которой прогнозируются средневзвешенная СЃРєРѕ-рость, возвышение наружного рельса для перспективных условий эксплуата-ции, соотношение скоростей движения для поездов разных категорий, что дает возможность уменьшить общее воздействие подвижного состава РЅР° путь Рё СЌРєСЃ-плуатационные расходы. Результаты моделирования свидетельствуют Рѕ том, что РїСЂРё разделении РіСЂСѓР·РѕРІРѕРіРѕ Рё пассажирского движения Рё специализации направлений для пере-РІРѕР·РѕРє меняются скорости движения, параметры поездопотока, что вызвало РЅРµ-обходимость пересмотра Рё корректировки параметров кривых: возвышения РЅР°-ружного рельса, длин переходных кривых Рё величины минимально допустимо-РіРѕ радиуса. Предложен метод рационального распределения поездопотоков между параллельными ходами, который позволяет обоснованно выбирать наиболее выгодный вариант РїРѕ нескольким критериям одновременно, Рё дает РІРѕР·РјРѕР¶-ность решать поставленные Укрзализныцей задачи, уменьшив РїСЂРё этом РЅР° 12…21 % расходы РЅР° реконструкцию, пробег поездов Рё содержание пути. Теоретические Рё практические результаты использованы РїСЂРё выполнении шести научно-исследовательских работ РїРѕ заданию Укрзализныци, Приднепро-РІСЃРєРѕР№ Рё Львовской железных РґРѕСЂРѕРі.
EN: SUMMARY The dissertation is devoted to development of a method of formation of the ra-tional scheme of mastering by transportations for parallel railway lines at introduction on one of them high-speed movement of passenger trains, to research of features and increase of overall performance of a railway way at redistribution of freight traffics between parallel railway to the directions with determination of parameters of the plan of the line. For comparison of versions of the solution of a problem of differentiation of cargo and passenger traffic the new criterion which is based on application of a com-plex indicator of work of forces of interaction of a way and a rolling stock that gives the chance to estimate wear of travelling infrastructure from a stream of trains for a long time of operation of the railway was used. The method of rational trains sequence distribution between parallel courses that gives the chance to choose reasonably the most suitable option by several criteria at the same time is offered, and gives the chance to solve the problems put by Ukrzal-iznytsa, having reduced thus expenses on reconstruction, run of trains and the main-tenance of a way. The received scientific results, are offered methods of researches and the scheme of classification of the directions can be used when developing recommenda-tions about increase of throughput of the directions, an economic assessment of influ-ence of intensity of cargo and passenger traffic on wear of infrastructure of railway transport, unification of weight and length of trains on the main directions of the railways of Ukraine.
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SHIH, CHENG-HUA, and 施承華. "The Research on High-speed Rail Track Deformation Survey." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/2645bj.

Повний текст джерела
Анотація:
碩士
建國科技大學
土木與防災研究所
107
This research is primarily dealing with the influence on the high-speed rails from the increasing service time, artificial activities, and other environmental elements. Also, it will deal with the influence on its running safety and riding comfort from the problems of deterioration and distortion of the rails. All the data obtained in this research came from the collection made by the orbital examination vehicle, and the sections which need adjusting are determined by the High-speed Railroad Company. With the help of the high-precision electronic level and the total station to obtain more precise data, as well as the calculation of track deviation quantity, and the analysis of the data, we can figure out the sections of the track lines which need to be adjusted. The data will then be offered to corresponding department to do the necessary adjustments. After the adjustments, a further surveying will be done to make sure if the rails adjusted meet the required standards. In this study, the data required for orbital adjustment, using the automatic station theodolite and electronic level measurement, can not only meet the requirements of adjusting the accuracy of the track measurement data, but also save manpower requirements and costs, so that the contractor has more construction. The contractor has more space for construction. Keyword:High Speed Rail, Electronic level, Total station
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32

Chia-Hsien-Ho and 何家賢. "Optimization Model for Track Alignment in High-speed Railway System." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/17965729966697647802.

Повний текст джерела
Анотація:
碩士
國立中興大學
土木工程學系所
103
The alignment of high-speed rail tracks change as the time passes. The tracks continuously face with detrimental conditions and cause irregularity, such as earthquake, degrade of pre-stressed concrete bridges, soil subsidence and so on. Track alignment deterioration will affect not only the comfort of passengers but also the safety of train operations. On the other hand, irregularity of tracks cause vibration and impact between tracks and wheels which seriously reduces the life of train system and track components as well as increase the consumption of energy. As a result, the track alignment needs to be improved to maintain the safety and reduce operational cost of the high-speed rail system. The current procedure of Taiwan High Speed Rail (THSR) to rectify irregularity of alignment is by inserting a combination of shims with 14 kinds of different thickness. The rails are therefore adjusted up or down to improve the alignment. The proposed alignment indexes include 1.3m, 10m and 40m versine. How to choose the most appropriate combination of shims is the main goal of this study. For each track fixture, hounded of thickness of shim could be chosen. Hundreds of binary decision variables are used to describe which kind of thickness is chosen at one fixture position. Usually hundred meters of track with hundreds of fixtures need to be aligned all together. Therefore, this is an optimization problem with ten thousands discrete decision variables, which is very difficult to solve directly. To over this problem, a linear programming model is first proposed to produce the appropriate conjectured thicknesses of shims in the fixtures. Then 5 shim thicknesses most closed to the conjectured thicknesses are organized to conduct a binary programming model to solve this problem. This research first reviews the current track maintenance procedures of THSR. A model integrating linear programming and binary programming is described in detail. Finally a project of track alignment is demoed to validate the developed model. It concludes that the proposed model can provide sophisticated track alignment plan. Keywords: Track alignment irregularity;Taiwan High Speed Railway. ;10m versine ;40m versine;Optimization
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33

Huang, Ren-Jeng, and 黃仁政. "Dynamic Response of Track System under High-Speed Moving Loads." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/39448068420857608614.

Повний текст джерела
Анотація:
碩士
國立成功大學
土木工程學系碩博士班
95
With the trend of increasing speed and capacity, the railway structures are facing more and more challenges. When the train speed approach the critical wave velocities of the track structure, the deformations of track systems may increase dramatically due to resonance and result in track failure and even derailments. This study applied the finite element analysis package, ABAQUS, to model track structures loaded by high speed moving suspended mass to investigate the interactions among track structure parts and track responses.   The results of this study showed that raising train speed may significantly increase track vibrations. When the train speed approached the critical velocity of the track system, the analysis considering multiple axle loads illustrated different train-track behavior from the results with single moving axle. It was also concluded that stiffening track rigidity by improving subgrade quality is a cost-efficient way to cope with the challenges on track structures in the high-speed railway transportation era.
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34

Chi-FongHuang and 黃啟峰. "Research of Track Alignment Managnment Technology in High Speed Railway." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/40478675055875543161.

Повний текст джерела
Анотація:
碩士
國立成功大學
工學院工程管理專班
98
High speed railway requirement is growing up around the world in recent year. Following the tendency towards of high speed railway technology, it is necessary to upgrade the requirement of safety and riding quality in the view of track. Track alignment deterioration will be influenced by revenue operation time, environment or 3rd party construction…The deterioration will become track alignment irregularity and operation safety and riding quality concern caused. How to keep riding quality in good condition? It is necessary to create good track alignment management method to help. When riding quality can be kept in good condition, people will be more confidence in riding high speed railway for transportation. Therefore track alignment management technology is quite important in railway corporation, especially in high speed railway. After study track alignment criteria around the world, some of high speed railway developed nations used track alignment criteria not only take middle-wavelength irregularity that related to operation safety into consider but also vertical and horizontal long-wavelength track alignment irregularity that related to riding quality. For the regional track quality index, high speed railway developed nations also used vary methods to evaluate track alignment quality and plan the re-alignment maintenance when out of tolerance was found. Maintain track alignment inside long-wavelength criteria and track quality index can ensure good operation safety and riding quality in the same time. As simulation, it is confirmed 40m versine for long-wavelength track alignment criteria and standard deviation evaluation for regional track quality index can be applied in Taiwan High Speed Railway. Therefore it is suggested to add riding quality criteria into consider when new high speed railway route develop. Regarding the additional maintenance cost, it is possible to seek help in some ways Ex. Actual maintenance cost is higher than evaluation, reduce refund or extend operation period.
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35

Liu, Yu-Wei, and 劉鈺韋. "High Speed Frame Grabber and Sleepers Positioning for Track Monitoring System." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/45344297730003781871.

Повний текст джерела
Анотація:
碩士
國立臺灣科技大學
電機工程系
98
In recent years, along with the improvement of the image processing technology, image recognition has already become the mainstream method of object inspection. The quality of images will directly affect the image-recognition rate. In track monitoring systems, track conditions will affect driving security of trains. Therefore, the conditions of track systems are very important. In this research, a high speed frame grabber system and the triggering rate of its line scan camera can be adjusted to match the vehicle speed so that the pixels per inch of an image are fixed. Sleepers locations can be detected by the sleeper positioning system developed in this research and transmitted to computer terminals for inspection and repair by engineering staff. The hardware equipment includes a line scan camera, an image acquisition card, light sources, a contrast sensor, a distance sensor, and an SOPC (System On a Programmable Chip) development board. Both the exposure time control system and sleeper positioning control system are designed based on an FPGA (Field-Programmable Gate Array) core. The designed system can acquire clear high-speed images of objects moving with high speed, and acquire positions of sleepers while the vehicle speed changes dramatically. The experimental results confirm the feasibility of using line scan cameras for railway vehicles.
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36

Araújo, Nuno Miguel Faria. "High-speed trains on ballasted railway track : dynamic stress field analysis." Doctoral thesis, 2011. http://hdl.handle.net/1822/12388.

Повний текст джерела
Анотація:
Tese de doutoramento em Engenharia Civil (área do conhecimento em Geotecnia)
The analysis of ballasted railway structures still demands many improvements towards preceding an accurate estimate of its global behavior, i.e, towards reproducing the real performance of the materials and the structure. Furthermore, in the design process, ultimate/serviceability limit states and life cycle costs should be attended. As a result, a wide range of research works are being introduced. This work contributes to the improvement of these processes throughout laboratory and numerical experiments aiming to investigate (with particular emphasis) on the dynamic stress field analysis, particularly the characteristic stress paths followed by granular elements below a typical track structure under the passage of a High-Speed Train (HST). The experimental laboratory work allowed, by means of a high-precision cyclic triaxial stress-path apparatus, the definition of the elastic domain of a foundation soil. The numerical experiments were carried out using an elastic frequency domain model and an elastoplastic time domain model, validated with in situ data obtained by vibration measurements in a HST railway line. These numerical models were used to analyze the influence of stiffness of the foundation (elastic domain) and structural layers of railway granular materials (elastic or elastoplastic domains) in the stress field, clearly showing that the stress response is a function of the selected constitutive law. Furthermore, the linear elastic assumption for the foundation soil was found to be questionable, suggesting that further investigation is required.
A análise de estruturas ferroviárias balastradas exige melhorias que a tornem capaz de reproduzir o comportamento global, i.e., que seja possível a reprodução do desempenho real dos materiais e da estrutura. Além disso, no processo de dimensionamento, os estados limite de utilização/últimos e os custos de manutenção devem ser considerados. Como resultado, uma ampla gama de trabalhos de investigação está actualmente em curso. Este estudo contribui para a melhoria destes processos, através de experiências laboratoriais e numéricas que focam com particular ênfase o campo dinâmico de tensões induzido nas camadas granulares das estruturas ferroviárias, quando submetidas à passagem de um comboio de alta velocidade. O trabalho experimental laboratorial permitiu, por meio de um sistema triaxial cíclico de precisão capaz de aplicar qualquer trajectória de tensões, a definição do domínio elástico de um solo de fundação. Os trabalhos experimentais numéricos foram realizados utilizando um modelo elástico no domínio da frequência e um modelo elasto-plástico no domínio do tempo, validados com medições in situ de vibrações numa linha ferroviária de alta velocidade. Estes modelos numéricos foram usados para analisar a influência da rigidez da fundação (domínio elástico) e das camadas granulares estruturais da via ferroviária (domínios elástico ou elasto-plástico) no campo de tensões, mostrando claramente que a resposta é função da lei constitutiva seleccionada. Além disso, a assumpção de comportamento elástico linear para o solo de fundação é questionável, requerendo-se investigação adicional.
Fundação para a Ciência e a Tecnologia (FCT) - POCI/ECM/1114/2004
Gabinete de Relações Internacionais da Ciência e do Ensino Superior - GRICES/CNRS
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37

Chen, Wen-liang, and 陳文亮. "A Study of Rail Irregularity Measurement of High Speed Rail Slab Track-A case Study of Taiwan High Speed Rail Project." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/44379771190148646236.

Повний текст джерела
Анотація:
碩士
逢甲大學
交通工程與管理所
95
Taiwan High Speed Rail started its operation on March 2, 2007. To ensure the safe operation and comfortable rides, the inspection of rail irregularity is crucially important. The Japanese AF-55 slab track and the German Rheda 2000 slab track are both used in Taiwan High Speed Rail. These two kinds of slabs are very different from each other in their construction methods, rehabilitation, and maintenance.Due to the repeated high speed heavy load, the irregular deformation of the rail geometry, such as irregularity in gauge, alignment, superelevation, surface and twist etc, is inevitable. Therefore, to dominate the situations of the irregularity and keep it in a reasonable range becomes the primary job. This study uses the data collected from 10 meter chord based on versine inspection method by rail-inspection car EM120, and then derives 20 meter chord and 40 meter chord from the data by applying Multiple-Precision floating point number arithmetic. The collected data will be divided, every 200 meters as one section, in terms of the different chords, types of slabs, and types of constructions. Then these data will be analyzed and calculated to obtain the average value, maximum value and P value. Finally, the rail irregularity in these two types of slab will be found. The study shows the causes and the characteristics of the rail irregularity between Japanese slab track and German slab track. Also this study discovers the unique reasons of the rail irregularity happening in the two special slabs and their topographic conditions. Meanwhile, this study can rapidly find out the locations and possible causes of rail irregularity, which is high-priority in rail rehabilitation. Furthermore, this result of the study can be used in rail maintenance system in order to increase the safety of operation and comfortable rides, and to extend the life-cycle of rail and rolling stocks.
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38

RANI, PRITI. "STATIC ANALYSIS AND PARAMETRIC INVESTIGATION OF BALLASTLESS RAILWAY TRACK FOR HIGH SPEED RAIL." Thesis, 2019. http://dspace.dtu.ac.in:8080/jspui/handle/repository/16767.

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Анотація:
Increasing population and high population density of India has put intense pressure on existing railway track. The are operating at a way more than their capacity and this has strained many rail lines which leads to derailment and other mishaps. This high population density suits High speed railway. To fight with increased traffic with regard to speed and loading, the stresses variation in various components must be known accurately to evaluate useful life of each component for its life assessment. To asses this detailed analysis is necessary to develop methodology for every track component under actual loading condition. In this thesis a comprehensive study on the behavior of ballastless track structure for high speed train under stationary load is carried out. Finite element analysis is used for analysis. Different track systems are considered, and the performance of track components analyzed under stationary wheel load. Deflection and stresses are the parameters which is used to analyze the performance of track system. Parametric investigation is carried out for the variation in material properties to study the effect of behavior the track under the effect of different material. Present investigation revels increase in stiffness of rail pad and modulus of subgrade decreases the deflection in track component while increase in modulus of elasticity of concrete slab and CAM layer shows no change in terms of deflection. It is also seen that with increase in all the parameters the contact stress in the rail decreases. But in concrete slab increase in stiffness of rail pad and modulus of elasticity of concrete slab increases the equivalent stress.
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39

CHIEH, CHEN SHENG, and 陳聖杰. "The Analysis of Vibration Caused by High-speed Train Passing the Slab Track." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/75016938871689803845.

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40

CHIN-CHANG, CHIU, and 邱欽璋. "A Study of the " Slab Track Rail " in Taiwan High Speed Rail construction." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/05481644486400482780.

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Анотація:
碩士
中華大學
土木工程學系碩士班
92
Taiwan High Speed Rail (THSR) has proposed NT$500 Billion on BOT Rail Transportation System which makes it the first and ever highest budget in the world of its kind. Furthermore, THSR adopt the Slab Track Rail Transportation System with speed over 300 km per hour (Km/Hr) which will only take 90 minutes from Taipei to Kao-hsiung with the total distance of 345 km; this makes Taiwan a metropolis throughout entire island. The major structures of the Slab Track System include roadbed, stopper, cement asphalt, tract slab,rail,railslab and fastener. The advantages of the Slab Track System possess high capacity, high speed,on-time, weather resistance, higher safety and maintenance free. However, THSR has limited knowledge and experience on the Slab Track System imported from Japan, so it is extremely important to establish systematic database and expertise at this field. This thesis is focus on THSR’s building material, construction techniques, machinery and variety skills in reference of Shinkansen in Japan and also detail discussed on construction of concrete bed for sustaining rail. The content include following subjects: quality control of sustaining rail, job-site prefabrication slab inspection techniques, flexible supporting material under pre-cast rail slab, the quality of CA ( cement asphalt) and the features of high speed rail system. This thesis has also made recommendations on human resource distribution of rail slab construction. I truly expect this thesis can serve any practice reference in construction of data collection and construction techniques. Key words: high-speed rail transportation , slab track, flexible supporting material, CA (cement asphalt) mortar
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41

Hsu, Jia-Lun, and 許家綸. "Analysis of Signal Leakage of Audio Frequency Track Circuit for High-Speed Rail." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/52206397064649999142.

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Анотація:
碩士
中原大學
電機工程研究所
100
The audio frequency(600Hz) signal is transmitted by the signalling system on the high speed track circuit, which can specify whether the track circuit being occupied. If any, the next train can not enter the occupied track circuit(about one kilometer) to prevent from the head-on collision. When the rail fastening assembly(RFA) is polluted badly or is covered with heavy rain, the audio frequency signal may leak out of the RFA as to the signalling system making the incorrect judgement that the track circuit were occupied. This thesis intends to simulate the leakage of audio frequency signal from the RFA and analyze the leakage route and the audio frequency voltage and current on the track circuit with comparison to the measurement results. Two models are built in this study. The first model is used for simulating the signal voltage and current in whole track circuit; the second model for simulating the potential distribution and the leakage current of one RFA. We also design the data exchange interface between the two models. Then the track circuit model uses the RFA model results to analyze the leakage resistance, based on which to evaluate the whole track circuit voltage and leakage current. The developed models to analyze the audio frequency signal’s leakage of high speed track circuit, can be an important evaluation tool to prevent the leakage of audio frequency signal from the track circuit.
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42

MING, SHIU TZ, and 徐子明. "Dynamics Characteristics Of Slab Track And It''s Dynamics Responses Under High -Speed Railway." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/70420480212181298242.

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Анотація:
碩士
國立臺灣大學
造船及海洋工程學研究所
89
The study of modeling and structural analysis of the dynamic characteristics of the slab track and its dynamics responses under high-speed railway is presented. The slab track is modeled by layered beam with viscoelastic foundation and the natural frequency; mode shape and resonance velocity can be solved with dynamic stiffness matrix of the layered beam structure. With the derivation of the dynamic response under single moving load it can be obtained by applying the same theory that a high-speed railway passed through. Furthermore, the Japanese A-51 slab track will be used as an example to compute the dynamic responses under 3 kinds of high-speed railways: (1) the Japanese S.K.S., (2) the French T.G.V., and (3) the Germany I.C.E.
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43

Wang, Yi-Cheng, and 王翊丞. "Dynamic response of track structures in transitional sections induced by high speed moving trains." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/91509268167166951951.

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Анотація:
碩士
國立臺灣大學
工程科學及海洋工程學研究所
99
Taiwan High Speed Rail passes through the west side of Taiwan. In other to match up varied elevation of landforms, most of the rail structure are layed on viaduct, some of them are layed on tunnel or on land. The track structure between two type sections is called a transitional section, e.g., tunnel and land, or land and bridge. This thesis focuses on the dynamic response of transitional section induce by high speed passing train.   In this thesis, the transient dynamic finite element method code – LS-DYNA was used to analyze the dynamic response of track structure on different type of rail section induced by single moving carriage.   First, we simulate single carriage passing the bridge-land transitional section and land-tunnel transitional section, and observe the displacement, velocity, acceleration response of check points on different position of rail structure. Base on the dynamic response, we discuss the effect by two conditions - uneven rail track, and imperfect connection between concrete bed of track and foundation. Finally, we observe dynamic response of carriage traveling through transitional section. The result show that both conditions will cause dynamic response of structure in transitional section while the train is passing by. Imperfect connection between concrete bed of track and foundation cause significant effect on rail track structures. The effect on dynamic response of carriage cause by uneven rail track is noticeable.
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44

Huang, Guan-Lin, and 黃冠霖. "Low Droop Rate, High Speed Broadband Track-and-Hold Amplifiers Using Silicon Based Technique." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/jd5h2k.

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Анотація:
碩士
國立中央大學
電機工程學系
106
This thesis focus on the design and analysis of the low droop rate, high speed broadband track-and-hold amplifiers. The design goals of the proposed circuits are broadband, low droop rate and low dc power consumption. The circuit design, analysis, simulation, and measurement are completely presented in this thesis, and the discussion and conclusion are also addressed for the future works. The introduction and design principle of the THA will be presented in Chapter 2. A differential cancellation technique is proposed for the track-and-hold stage to reduce the feedthrough during the hold mode. To avoid charge injection, the dummy transistors are adopted in the track-and-hold stage. At the end of the Chapter 2, undersampling technique will be discussed. The proposed THA with clock buffer is frabricated using TSMC 40 nm CMOS general purpose process in Chapter 3.The common-gate amplifier is adopted to enhance the bandwidth of THA. Moreover, the common source topology is employed to enhance the gain and bandwidth of the THA. For the experimental results, the differential small-signal S-parameters, spurious-free dynamic range (SFDR) and time-domain waveform are performed to completely verify the simulations. The measured 3-dB bandwidths of the THA is 41 GHz with small-signal gain of -4.8 dB. The best SFDR is 49 dBc. The total DC power consumption is 104.1 mW, and the droop rate is 0.35 mV/ps.The chip size is 0.8× 0.9 mm2. The proposed THA is frabricated using TSMC 0.18 μm SiGe general purpose process in Chapter 4.The distributed amplifier is adopted to enhance the bandwidth of THA. The dc bias and device size selection is addressed with ideal component for the preliminary circuit simulation. Moreover, the Cascode topology is employed to enhance the gain and bandwidth of the THA. The Cascode topology can also improve the isolation during the hold mode. For the experimental results, the differential small-signal S-parameters, spurious-free dynamic range (SFDR) and time-domain waveform are performed to completely verify the simulations. The measured 3-dB bandwidths of the THA is 17 GHz with small-signal gain of -4.8 dB. The best SFDR is 54.8 dBc. The total DC power consumption is 180 mW, and the droop rate is 0.4 mV/ps.The chip size is 1 × 1.3 mm2. The proposed Master slave THA is frabricated using TSMC 0.18 μm SiGe general purpose process in Chapter 5. To improve the droop rate of the THA in Chpater 4, the THA is resimulated and combined as a master slave topology.The distributed amplifier is be changed to two stages, because three stages will cost a lot of size of the chip . The dc bias and device size selection is addressed with ideal component for the preliminary circuit simulation. Becauce of the dc level is too high for next stage, the cascode topology is changed to common source. For the experimental results, the differential small-signal S-parameters, spurious-free dynamic range (SFDR) and time-domain waveform are performed to completely verify the simulations. The measured 3-dB bandwidths of the THA is 10 GHz with small-signal gain of -5 dB. The best SFDR is 38.2 dBc. The total DC power consumption is 134 mW, and the droop rate is 4 μV/ps.The chip size is 2.6 × 1.8 mm2.
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45

BHARDWAJ, SAURABH. "BONDGRAPH ANALYSIS OF DYNAMIC INTERACTION BETWEEN THE CONCRETE SLAB AND SUBGRADE FOR HIGH SPEED TRACK." Thesis, 2019. http://dspace.dtu.ac.in:8080/jspui/handle/repository/16703.

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Анотація:
In the last few years there has been a major shift from petrol, diesel vehicles to electric vehicles and other alternate fuel vehicles, because of the limited availability of fossil fuels. High speed train is one such example of electric vehicles, that have witnessed an increasing demand in present times, specially in urban cities, due to its various advantages, namely, ease of use, economical, time saving, and comfortable. As a result of these factors, analysis and study of such systems, for their optimal performance and more economical operation, is of paramount concern. The present-day study is aimed to elucidate the effect of vehicle speed on the deflection between the concrete slab/subgrade contact, and track components. The interaction between the slab and the subgrade, affects the safety and comfort of the vehicle. The dynamic analysis of a three-dimensional, modal Bond graph model of the high-speed track components is carried out in this article. The concrete slab is modelled as a Euler-Bernaulli beam, and the beam is divided into 5 nodes. Two parallel slabs are joined with cement-asphalt mortar between them. The hence developed model is then simulated for train velocities ranging from 200kmph to 500kmph. The bond graph modelling and its simulation, is performed using SYMBOLS SHAKTI software.
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46

Lin, Yu-An, and 林俞安. "Design and Analysis of High Speed High Linearity High Resolutoin Track-and-Hold Amplifier in III-V andSilicon-Based Processes." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/d7b9d4.

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Анотація:
碩士
國立中央大學
電機工程學系
106
Several microwave and millimeter wave (MMW) high linearity track-and-hold amplifiers (THAs) for high speed data conversion systems are presented in this dissertation. Design, investigation and analysis of THAs shown in this dissertation are verified by the experimental results. The introduction and design considerations of THA are demonstrated in Chapter 2 in details. A compact DC-to-82.4-GHz broadband amplifier using 0.15 μm GaAs E-mode PHEMT process is demonstrated in Chapter 3. The amplifier is implemented in common-source (CS) configuration with bandwidth extension technique. The frequency response and input and output impedances of the amplifier are investigated to obtain the design methodology. The amplifier exhibits a high gain-bandwidth product (GBP) of 328 GHz with a chip size of 0.7 × 1 mm2. Moreover, the amplifier is evaluated using pseudorandom bit stream (PRBS) signal with a data rate up to 40 Gbps. The proposed amplifier has potential for the high-speed data rate transmission due to its superior performance. A broadband high-speed high-linearity THA is presented in Chapter 4 using 0.18 μm SiGe process. A switched emitter follower (SEF) track-and-hold (T/H) stage with cascode stage is adopted to achieve high resolution for analog-to-digital conversion. A modified Darlington amplifier with peaking technique is used to enhance the input bandwidth. With a DC power consumption of 94.3 mW, the proposed THA demonstrates a 3-dB input bandwidth from DC to 27 GHz, a maximum spurious-free dynamic range (SFDR) of 45 dBc, and a minimum total harmonic distortion (THD) of -43.9 dBc. The proposed circuit has potential for high-speed sampling rate as using time-interleaved architecture due to its superior performance. Chapter 5 presents the design and analysis of the first GaAs-based THA. The conventional switched source follower (SSF) T/H stage is modified to enhance the sampling rate and resolution. The modified SSF T/H stage is designed and investigated to further reduce input-dependent timing jitter existed in the conventional SSF. Moreover, by using the differential topology, the even mode harmonic distortion is successfully suppressed and the SFDR and THD are improved. With the distributed amplifier (DA)-base input buffer and source follower-based output buffer, the proposed THA features a bandwidth from DC to 16 GHz, a maximum SFDR of 46 dBc and a maximum sampling rate of 13.5 GS/s. In Chapter 6, a 40 nm CMOS high speed high dynamic range THA is proposed using a differential feed-through cancellation technique. The simulated isolation is approximate to infinity over the input bandwidth as the THA is operated in the hold mode. The linearity and droop rate are enhanced due to the feed-through cancellation. With a sampling rate of 50 GS/s and an input frequency of 5 GHz, the SFDR and THD are better than 47.6 dBc and −44 dBc, respectively. The simulated input bandwidth is up to 60 GHz, and the total DC power consumption is 396 mW. The measured results and resimulated results with several significant layout considerations are detailed as well. The proposed THA can be suitable for the handheld electronic applications, and the circuit performance can be compared to the advanced silicon-based THAs due to its high speed, good linearity, and low DC power. Lastly, the future work and the conclusions are addressed in Chapter 7.
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47

Chung, Yu-Lun, and 鍾毓倫. "Design of High-Speed ADC with distributed Track-and-Hold Pre-comparator in CMOS 0.18µm." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/12828813510875106840.

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Анотація:
碩士
中原大學
電子工程研究所
97
This work presents a new flash analog-to-digital converter (ADC) with distributed track-and-hold pre-comparators (THPCs). Utilizing the proposed architecture, the loading capacitances of the ADC front-end sampling sub-circuits can be markedly reduced, thereby improving operation speed. In a standard 0.18µm CMOS process, a 1.6GS/s 6-bit flash ADC is implemented to demonstrate the feasibility of the proposed distributed THPC architecture. The equivalent input capacitance of each input port of the proposed flash ADC is only 400fF, which is an easily driven interface. Furthermore, clocked timing buffers are inserted in the encoder to accelerate the operational speed of the proposed flash ADC. Post-layout simulation results demonstrate that the proposed ADC achieves an SNDR of 35.81dB, which is 5.66 ENOB at 1.6GS/s with a 793.8MHz input signal frequency. The proposed ADC consumes 310mW from a 1.8-V supply at full operating speed.
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48

Cunha, J. P. "Modelling of ballasted railway tracks for high-speed trains." Doctoral thesis, 2013. http://hdl.handle.net/1822/24858.

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Анотація:
Tese de doutoramento em Engenharia Civil
Ballasted railway tracks are one of the most common structures travelled by high-speed trains. The high circulation speeds of these trains lead to increased vibrations in the tracks and nearby structures, which can affect the serviceability and maintenance costs of the tracks. There is a growing demand for a means of accurately predicting the performance of ballasted railway tracks in train circulation. Numerical simulations are a highly effective means of predicting track response and the propagation of vibrations to the free field. However, numerical simplifications often prevent these models from performing additional in-depth analyses of three-dimensional track response or non-linear behaviour of the track ballast and foundation soil. This thesis aims to expand the knowledge of ballasted railway track response by performing 3D non-linear railway track simulations and investigating the importance of non-linear material behaviour in numerical predictions. The first part of the thesis concentrates on the elastodynamics of railway track response to moving loads and the numerical accuracy of 3D Finite Element meshes of railway tracks. The advantages and disadvantages of 3D Finite Element simulations for these structures are highlighted and the cases for which they are suitable are identified. The second part of this thesis focuses on non-linear ballast and soil response using time-domain simulations. The study of ballast behaviour is performed using a constitutive model in which the separated consideration of yield surfaces and pressure dependent Young’s modulus, facilitates the identification of their individual influences on track response. The 3D nature of the model also enables the study of the stress and strain distribution in ballast, in the transversal and longitudinal directions of the track, which provide insight into the difference in behaviour between ballast under a sleeper and ballast between two sleepers. The evaluation of the non-linear soil response is conducted using a cyclic non-linear model that was implemented in the Finite Element software. This model examines the spatial distribution and time history of the stiffness degradation experienced by the soil during the passage of a train axle. Finally, the simulation of the integrated non-linear soil and ballast material models demonstrates the influence of non-linear behaviour at different circulation speeds.
Vias férreas balastradas são uma das principais estruturas nas quais circulam os comboios de alta velocidade. A grande velocidade de circulação destes veículos induz vibrações acrescidas na via-férrea e estruturas circundantes, que podem afetar a eficácia e custos de manutenção da via. Consequentemente é cada vez maior a procura de meios precisos de previsão da resposta de vias férreas à passagem de comboios de alta velocidade. As simulações numéricas são bastante eficientes para prever a resposta da via e a propagação de ondas no solo. No entanto algumas simplificações numéricas impedem muitas vezes estes modelos de permitir análises mais detalhadas sobre a resposta tridimensional da via e o comportamento não-linear do balastro e do solo de fundação. Este trabalho contribui para aprofundar o conhecimento existente do comportamento de vias férreas através de análises 3D não-lineares e do estudo da importância do comportamento não-linear dos materiais nas previsões numéricas. A primeira parte do trabalho visa essencialmente o estudo do comportamento plastodinâmico das vias férreas e da precisão numérica de malhas em Elementos Finitos 3D para a simulação das vias. As vantagens e desvantagens das simulações em Elementos Finitos 3D são discutidas e são identificados os propósitos para os quais estas simulações são mais adequadas. A segunda parte do trabalho foca-se no estudo da resposta não-linear de balastro e solo de fundação através de simulações no domínio do tempo. O estudo do comportamento do balastro é feito através de um modelo constitutivo no qual a consideração em separado de superfícies de cedência e da variação do módulo de Young com a tensão média permitiu identificar a influência de cada na resposta da via. A análise tridimensional permitiu também estudar a distribuição de tensões e deformações na direção transversal e longitudinal da via, facultando uma análise do diferente comportamento de balastro debaixo de uma travessa e de balastro situado entre duas travessas. O estudo do comportamento não-linear do solo é feito através de um modelo não-linear cíclico que foi implementado no software de Elementos Finitos. Isto permitiu o estudo da distribuição espacial e temporal da degradação da rigidez que o solo sofre durante a passagem de um eixo de um comboio. Finalmente a simulação integrada do comportamento não-linear do solo e do balastro permitiu compreender a importância do comportamento não-linear em função da velocidade de circulação do comboio.
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49

Li, Chang-Ray, and 李承叡. "Research on Linearity And Droop Rate for Silicon Based High Speed Broadband Track-and-Hold Amplifiers." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/th2xvx.

Повний текст джерела
Анотація:
碩士
國立中央大學
電機工程學系
107
This thesis mainly discusses the application of high-linearity track and hold amplifiers for high-speed data conversion systems in microwave and millimeter-wave bands, and focuses on the improvement of rate-of-change and linearity. The proposed design, research and theoretical calculations will be verified with on wafer measurement results. The introduction and design considerations of THA includes the operating principle, important parameter descriptions, design considerations, and frequency-down sampling applications will be presented in Chapter 2. The proposed THA with clock buffer is frabricated using TSMC 40 nm CMOS general purpose process in Chapter 3. Compared to the traditional switched-capacitor (SC) track and hold(T / H)stage. A differential cancellation technique is proposed for the track-and-hold stage to reduce the feedthrough during the hold mode. To avoid charge injection, the dummy transistors are adopted in the track-and-hold stage. The clock buffer uses a distributed amplifier with wide bandwidth and good impedance matching, makes the high power input sine wave turn out as a square wave. The input and output buffer use common-source amplifier with active inductor peaking technology to enhance the track-mode bandwidth without taking up extra circuit area. The simulation results show that the measured 3-dB bandwidth of the THA is 42 GHz with small-signal gain of 0 dB. The best SFDR is 46 dBc. The total DC power consumption is 217.2 mW. The chip size is 0.83×0.94 mm2. The proposed THA is frabricated using TSMC 0.18 μm SiGe general purpose process in Chapter 4. Several performance enhancement techniques are investigated including operated speed extension, linearity improvement, and resolution enhancement. Compared to the traditional switch emitter-follower (SEF), a cascode transistor is added to the switch stage to reduce the clock feedthrough voltage error. The differential cancellation technique is used to further improve the resolution and analyze the improved SEF optimal transistor size. Moreover, the common source with active inductor peaking topology is employed to enhance the gain and bandwidth of the THA. The proposed THA has a 3-dB bandwidths of the THA is 34 GHz with small-signal gain of -4.8 dB. The best SFDR is 44 dBc. The total DC power consumption is 120 mW. The chip size is 1.14 ×0.71 mm2. The proposed Master slave THA is frabricated using TSMC 0.18 μm SiGe general purpose process in Chapter 5. To improve the droop rate of the switch stage in Chpater 2, the THA is resimulated and combined as a master slave topology. In order to enhance the operated speed, the modified Darlington-based input buffer is used to release low pass response. The output buffer is designed by using the source follower topology which features low leakage current and broadband output matching. The measured 3-dB bandwidths of the THA is 40 GHz with small-signal gain of -5 dB. The best SFDR is 43.2 dBc. The total DC power consumption is 120 mW, and the droop rate is 4 μV/ps. The size is 2.135 × 0.865 mm2. Lastly, the future work and the conclusions are addressed in Chapter 6
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50

Liu, Yu-Cheng, and 劉育誠. "Research on high-speed broadband amplifiers for track-and-hold applications and millimeter-wave active integrated antennas." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/3kkxez.

Повний текст джерела
Анотація:
博士
國立中央大學
電機工程學系
104
Research on the broadband amplifiers, track-and-hold circuits, and active integrated antennas in microwave and millimeter-wave (MMW) are presented in this dissertation. Design and analysis of the broadband cascode distributed amplifiers (DAs) using GaAs heterojunction bipolar transistor (HBT) / high electron mobility transistor (HEMT) process are completely presented with experimented results in Chapter 2. The gain-bandwidth analysis of cascode gain cell is presented using HEMT-HEMT, HEMT-HBT, HBT-HEMT, and HBT-HBT configurations to improve circuit performance. A modified m-derived network and a HEMT-HBT cascode amplifier with inductive peaking technique are proposed to enhance the gain and bandwidth of the DA. The dc bias networks of the DA are fully integrated in a single chip without off-chip bias-T or bias components. The DAs are designed and fabricated achieve a bandwidth from DC to 43.5 GHz with average gain of 8.5 dB, and the Output power 1-dB compression point is 8 dBm. Moreover, the DA is successfully evaluated with an eye diagram measurement up to 12.5 Gbps, and demonstrates good transmission quality. The DAs achieves broad bandwidth, good flatness, low group delay and good transmission quality. The DAs are suitable in the modern high-speed data communications due to the superior performance and the mass-production MMIC process. The basic concept of the track-and-hold amplifier is introduced in Chapter 3. Two high-speed track-and-hold amplifiers (THAs) with high spurious-free dynamic range (SFDR) are presented in Chapter 4. The THAs are realized in advanced 65 and 90 nm CMOS processes with high speed and low dc power consumption. The DA is employed in the THAs as an input buffer, and the input bandwidth is highly improved up to 19.6 GHz. The analysis of linearity and bandwidth for the track-and-hold stage is presented to improve the SFDR and linearity. The device size of the switch is properly selected to enhance turn-on bandwidth and high linearity. The analysis of input buffer is addressed with common-source, cascode, and distributed gain stages. The first THA is designed using 65 nm CMOS process with common source and cascode stages as input and output buffers, and it demonstrates an input bandwidth of 7 GHz and a SFDR of 40.9 dB. The second THA is designed in 90 nm CMOS process with a DA as input buffer, and it demonstrates an input bandwidth of 19 GHz and a SFDR of 44.5 dB. The proposed THAs feature broad bandwidth, compact chip area, high SFDR, high linearity, and high sampling rate, and they are suitable in the hand-held instruments. Two MMW oscillation-type active integrated antennas (AIAs) are design and fabricated in the 0.15-μm GaAs pHEMT process presented in Chapter 5. The first AIA is composed of a differential voltage-controlled oscillator (VCO) and a planar-Yagi antenna, the impedance matching between the two components is 50 Ω. For the second AIA design, the antennas is designed using a loop antenna, and also the antenna is designed as an inductance-capacitance (LC) tank of the VCO. The impedance matching between the differential VCO and the loop antenna is addressed in Chapter 5. The operation frequencies of proposed AIAs are in 69.7 and 40.7 GHz, and the effective isotropic radiated powers (EIRPs) of -13.2 dBm and -2.7 dBm, respectively. The proposed methodology is suitable for the simple MMW wireless personal area network applications.
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