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Number of results: 21
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Abstract

Safety and operation efficiency of the particle accelerators strongly depend on the quality of the supplied electric current and is affected by the electric properties of all elements of the circuit. In this paper the capacitance of the superconducting bus-bars applied in the cryogenic by-pass line for the SIS100 particle accelerator at FAIR is analysed. The unit capacitance of the bus-bars is calculated numerically and found experimentally. A 2D numerical model of a cross-section of the cable is applied. The capacitance is found with three methods. The stored energy, electric displacement field and charge gathered on the surfaces of the device are calculated and analysed. The obtained values are consistent. Experimental measurements are performed using the resonance method. The measuring system is undamped using a negative conductance converter. Small discrepancies are ob- served between numerical and experimental results. The obtained values are within the requirements of the accelerator design.

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Authors and Affiliations

Łukasz Tomków
Stanisław Trojanowski
Marian Ciszek
Maciej Chorowski
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Abstract

The ILC is an immense e+e- machine planned since 2004 by a large international collaboration, to be potentially built in Japan [1]. The gigantic size of the whole research infrastructure, the involved human, technical and financial resources, and the pressure of new emerging and potentially soon to be competitive accelerator technologies, make the final building decision quite difficult. A vivid debate is carried on this subject globally by involved accelerator research communities. The European voice is very strong and important in this debate, and has recently been essentially refreshed by clear statements in a few official documents [2]. The final HEP European Strategy Document is just under preparation. This paper is a very modest and subjective voice in this debate originating from Poland, which around 50 researchers are present at the list of 2400 signatories for the original ILC TDR document published in 2013 [3].

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Authors and Affiliations

Ryszard S. Romaniuk
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Abstract

This article has two outreach aims. It concisely summarizes the main research and technical efforts in the EC H2020 ARIES Integrating Activity – Accelerator Research and Innovation for European Science and Society [1] during the period 2017/2018. ARIES is a continuation of CARE, TIARA and EuCARD projects [2-3]. The article also tries to show these results as an encouragement for local physics and engineering, research and technical communities to participate actively in such important European projects. According to the author’s opinion this participation may be much bigger [4-27]. All the needed components to participate – human, material and infrastructural are there [4,7]. So why the results are not satisfying as they should be? The major research subjects of ARIES are: new methods of particles acceleration including laser, plasma and particle beam interactions, new materials and accelerator components, building new generations of accelerators, energy efficiency and management of large accelerator systems, innovative superconducting magnets, high field and ultra-high gradient magnets, cost lowering, system miniaturization, promotion of innovation originating from accelerator research, industrial applications, and societal implications. Two institutions from Poland participate in ARIES – these are Warsaw University of Technology and Institute of Nuclear Chemistry and Technology in Warsaw. There are not present some of the key institutes active in accelerator technology in Poland. Let this article be a small contribution why Poland, a country of such big research potential, contributes so modestly to the European accelerator infrastructural projects? The article bases on public and internal documents of ARIES project, including the EU Grant Agreement and P1 report. The views presented in the paper are only by the author and not necessarily by the ARIES.

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Authors and Affiliations

Ryszard S. Romaniuk
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Abstract

When conducting geodetic and gravimetric measurements, there is a problem of projecting them to the reference surface. Since the gravitational field is inhomogeneous under the real conditions, the problem arises of determining the corrections to the measured values of gravitational acceleration in order to use the obtained data for the subsequent solutions of projection problems. Currently, the solution to this problem is performed using a Bouguer reduction, which requires information about the internal structure of the upper layer of the earth’s surface, topography, etc. The purpose of this study is to develop a methodological approach that would allow to determine the reduction (projection) corrections for gravitational acceleration on technogenic and geodynamic polygons without using data about the distribution of surface layer density and topography. The research process is based on the use of mathematical analysis methods and a wide range of experimental geodetic and gravimetric measurements. In the course of the performed researches, an algorithm was obtained and a practical implementation of the determination of the corrections in the measured values of gravitational acceleration on the basis of geodetic and gravimetric measurements was carried out at the certain geodynamic polygon in order to bring all corrections to one level surface.

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Authors and Affiliations

Lev Perovych
Igor Perovych
Valeriy Gorlachuk
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Abstract

The cold start of the space GPS receiver, i.e. the start without any information about the receiver position, satellite constellation, and time, is complicated by a large Doppler shift of a navigation signal caused by the satellite movement on the Earth orbit. That increases about five times the search space of the navigation signals compared to the standard GPS receiver. The paper investigates a method of the acceleration of the GPS receiver cold start time designed for the pico- and femto-satellites. The proposed method is based on a combination of the parallel search in Doppler frequency and PRN codes and the serial search in code phase delay. It can shorten the cold start time of the GPS receiver operating on LEO orbit from about 300 to 60 seconds while keeping the simplicity of FPGA signal processor and low power consumption. The developed algorithm was successfully implemented and tested in the piNAV GPS receiver. The energy required for the obtaining of the position fix was reduced five times from 36 on to 7.7 Joules. This improvement enables applications of such receiver for the position determination in smaller satellites like Pocket Cube or femto-satellites with a lower energy budget than the Cube Satellite.

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Authors and Affiliations

Pavel Kovář
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Abstract

This paper presents an approach to the construction and measurements of electrodynamic and reluctance actuators. Executive elements were used as drives in a novel concept of a magnetomotive micropump. The paper discusses various aspects concerning the designation of parameters, control system, the explanation of physical phenomena, and the optimization of the basic elements for coil units. The conducted work describes the measurement system and the analysis of the derived values. The actuators were compared and the pros/cons of building the conceptual device were highlighted. The best solution to be used in the upcoming work concerning the construction of a magnetomotive micropump was chosen based on measurements, engineering aspects, layout control, and key parameters such as the piston velocity, energy stored in capacitors, and efficiencies.

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Authors and Affiliations

M. Szulborski
Ł. Kolimas
K. Bieńkowski
S. Łapczyński
Ł. Kozarek
K. Birek
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Abstract

The dependence of piezoelectric wave impedance on the rotation speed is investigated theoretically and numerically. The Coriolis force due to rotation is introduced into the piezoelectric motion equations, which is solved by the harmonic plane wave solution. It is shown that the wave impedance variations of longitudinal and transverse waves due to rotation are clearly different. The longitudinal wave impedance continuously increases with a small rotation ratio and one transverse wave impedance is almost irrespective of a rotation ratio. In contrast, the rotation applies a big impact on the other transversal wave impedances in the piezoelectric crystal which decreases monotonically with the rotation speed. Such characteristics are significant in piezoelectric transducers and sensors.
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Authors and Affiliations

Xiaoguang Yuan
1
Chaoyu Hao
1
Quan Jiang
1

  1. School of Transportation and Civil Engineering, Nantong University, Nantong, China
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Abstract

Ongoing energy measurement is one of the parameters such as: electron beam current, transporter speed, or scanning width, that must be recorded according to the conditions imposed in the accelerator validation procedure. Described measurement method based on the use of a secondary electron collecting electrode has been tested at the electron beam linear accelerator installation typically used for radiation sterilization. Data processing and presentation of the electron beam characteristics is based on the information obtained via dedicated pulse acquisition interface. The energy spectra parameters provide data for modeling and calculation of dose distribution for irradiation process optimization and also knowledge of accelerator RF alignment in case of service.
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Authors and Affiliations

S. Bułka
1
Z. Zimek
1

  1. Institute of Nuclear Chemistry and Technology, Centre of Radiation Chemistry Research and Technology, Warsaw, Poland
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Abstract

In order to the long-term stability of DSE for electroplating process, the lifetime equations were calculated from the results of the accelerated life testing, and the lifetime of DSE was predicted. The nano-embossing pre-treatment led to 2.65 times in the lifetime of DSE. The degradation mechanism of DSE with a thick metal oxide layer for applied highly current density process condition was identified. The improvement of durability of DSE seems to be closely related to adhesion between titanium plate and mixed metal oxide layer.
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Bibliography

[1] S.R. Park, J.S. Park, J. Korean Electrochem. Soc. 23, 1 (2020).
[2] J.E. Park, H. Kim, E.S. Lee, Materials 13, 1969 (2020).
[3] A.N.S. Rao , V. T. Venkatarangaiah, Environ. Sci. Pollut. Res. 21, 3197 (2014).
[4] J.Y. Lee, D.K. Kang, K.H. Lee, D.Y. Chang, Mater. Sci. Appl. 2, 237(2011).
[5] S.H. Son, S.C. Park, M.S. Lee, Arch. Metall. Mater. 62, 1019 (2017).
[6] Z. Yan, Y. Zhao, Z. Zhang, G. Li, H. Li, J. Wang, Z. Feng, M. Tang, X. Yuan, R. Zhang, Y. Du, Electrochimica Acta 157, 345 (2015).
[7] D.S. Kim, Y.S. Park, Electrode. J. Environ. Sci. Int. 27, 467 (2018).
[8] S.C. Park , Y.B. Park, J. Electron. Mater. 37, 1565 (2008).
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Authors and Affiliations

Sung Cheol Park
1 2
ORCID: ORCID
Yeon Jae Jung
1
ORCID: ORCID
SeokBon Koo
1
ORCID: ORCID
Kee-Ahn Lee
2
ORCID: ORCID
Seong Ho Son
1
ORCID: ORCID

  1. Korea Institute of Industrial Technology, Advanced Functional Technology R&D Department, Incheon, Republic of Korea
  2. Inha University, Department of Materials Science and Engineering, Incheon, Republic of Korea
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Abstract

Quality of electric current delivered to the magnets of a particle accelerator is essential for safety and reliability of its operation. Even small discrepancies strongly affect the properties of particle beams. One of the sources of the disturbances is the appearance of induced currents caused by the electromagnetic interactions between the elements of the machine. In this paper the calculations of induced currents in by-pass lines of a SIS100 particle accelerator are presented. In order to find the values of the currents the self-inductances and mutual inductances of the by-pass lines are found. Due to the complex geometry of the line, especially of Ω-shaped dilatations, the numerical approach was employed. The calculations show that the size of induced currents increases with the distance between the cables in an individual bus-bar. The maximum discrepancy of the magnetic field in a dipole magnet is found to be 7.7 μT. The decrease of distance between the cables allows one to obtain a discrepancy of 1.2 μT.

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Authors and Affiliations

Łukasz Tomków
Stanisław Trojanowski
Marian Ciszek
Maciej Chorowski
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Abstract

The study of the subdivision driving technology of a stepper motor and two types of typical acceleration and deceleration curves aims at optimizing the open-loop control performance of the stepper motor. The simulation model of a two-phase hybrid stepper motor open-loop control system is set up based on the mathematical model of the stepper motor, in order to let the stepper motor have the smaller stepper angle, two types of typical acceleration and a deceleration curve algorithm are designed for the real- time online calculation based on the subdivision driving technology. It respectively carries out the simulation analysis for their control effects. The simulation results show that the parabolic acceleration and deceleration curves have a larger maximum in-step rotation angle and the faster dynamic response ability in the same control period, and at the same time, the position tracking error of an intermediate process is smaller.

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Authors and Affiliations

Deode Zhang
Jingqi Wang
Lei Qian
Jun Yi
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Abstract

Sections of the superconducting magnets of the SIS100 particle accelerator, under construction at the Facility for Antiproton and Ion Research (FAIR), the Society for Heavy Ion Research (GSI), Darmstadt, are going to be connected with the by-pass lines. Each line will be used to transfer a two-phase helium flow and an electric current. The electric current will be carried by four pairs of superconducting Nuclotron-type cables. Fast-ramping currents are expected to cause the generation of heat within the cables. In this work the results of a numerical thermal analysis of a bus-bar are presented. The amount of heat transferred from the environment was found based on geometric dimensions of the line and applied insulation. The amount of hysteresis loss, generated in the cable during the operation under most demanding regime of the operation of the accelerator, was calculated. According to the amount of the generated heat, the amount of the hysteresis loss is low in relation to the heat generated in the superconducting magnets. Also it was found that the cable used in the line still retains a large margin of current-carrying capacity.

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Authors and Affiliations

Łukasz Tomków
Maciej Cholewiński
ORCID: ORCID
Marian Ciszek
Maciej Chorowski
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Abstract

On 2-3 May 2022 ARIES – Accelerator Research and Innovation for European Science and Society held its last annual conference in CERN summarizing 6 year long effort on the smart development of particle accelerator infrastructures in Europe. The whole series of Integrating Activities on accelerator infrastructures started in 2003 with preparations of CARE, then followed by EuCARD, TIARA, EuCARD2 and culminating with ARIES.
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Authors and Affiliations

Ryszard S. Romaniuk
1

  1. Warsaw University of Technology, Poland
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Abstract

CERN hosted on May 2-6, 2022, the first annual meeting of the H2020 I.FAST project to support innovation in the field of science and technology of particle accelerators. The project has a completely different character from its predecessors in this area of research. It was approved for implementation a year ago by the EC with the highest marks. It is worth looking at why projects such as ARIES, I.FAST and EURO-LABS are so easily accepted. This alleged ease of acceptance is an appearance. Behind the acceptance, in conditions of extremely tough competition, is the excellent organization of the submitting community that has been developed over the years, as well as the perfect, well-thought-out preparation of the material. The author, a participant in the ARIES and other EC projects in the field of particle accelerator science and technology, presents here, on specific examples, his subjective opinions on how to prepare materials for high-output projects for the EC FP. The author hopes that these remarks may be useful in the process of submitting research projects from Poland in international cooperation to the EC in the best possible way. The science and technology of particle accelerators is an excellent area of showing such examples because it is interdisciplinary and includes the following components: building of research infrastructure, applied physics, mechatronics, materials engineering, automation and robotics, electronics, ICT, innovation, cooperation with industry, and social.
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Authors and Affiliations

Ryszard S. Romaniuk
1

  1. Warsaw University of Technology, Poland
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Abstract

An active inerter-based suspension with acceleration feedback control is proposed in this paper, the time delay generated in the controllers and actuators is considered, which constitutes the time-delayed active inerter-based (TDA-IB) suspension. The dynamic equation of the TDA-IB suspension is established and is a neutral type of delay differential equation (NDDE) in which the time delay exists in the highest-order derivative. The stability analysis is conducted by calculating the number of unstable characteristic roots based on the definite integral stability method, the stable and unstable regions are determined. The effect of time delay and feedback gain on the dynamic performance of the TDA-IB suspension under harmonic, random, and shock excitations is studied in detail and compared with the parallel-connected inerter-based (PC-IB) and traditional suspensions. The results show that the TDA-IB suspension is asymptotically stable for smaller feedback gain and time delay, through increasing the feedback gain, the stable regions shrink, and a smaller time delay could cause the system to become unstable. Furthermore, the time delay could regulate the resonance peak around the unsprung mass natural frequency and generate multiple high-frequency resonance peaks. If the time delay is chosen appropriately and falls into the stable range, the TDA-IB suspension could improve the dynamic performance for the suspension stroke and dynamic tire load while having a deterioration for the vehicle body acceleration compared with the PC-IB and traditional suspensions.
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Authors and Affiliations

Yong Wang
1 2 3
ORCID: ORCID
Xian-Yu Jin
1
Yun-Shun Zhang
1
Hu Ding
4
Li-Qun Chen
4

  1. Automotive Engineering Research Institute, Jiangsu University, Zhenjiang 212013, China
  2. Vehicle Measurement, Control and Safety Key Laboratory of Sichuan Province, Xihua University, Chengdu 610039, China
  3. Provincial Engineering Research Center for New Energy Vehicle Intelligent Control and Simulation Test Technology of Sichuan, Xihua University, Chengdu 610039, China
  4. School of Mechanics and Engineering Science, Shanghai University, Shanghai 200444, China
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Abstract

This study investigates mechanical properties of accelerated cooled and self-tempered (AC-ST) H-type S275JR quality steel sections in HEA120 and HEB120 sizes. The cooling process is conducted with a specially manufactured system that sprays a coolant consisting of a water + compressed air mixture on the section surfaces. Cooling times were applied as 10 and 30 seconds using 4 and 12 bar compressed air + water at an average constant pressure of 5 bar and a constant flow rate of 0.08 kg/s. In the HEA120 sections, the highest cooling rate was obtained with 83°C/s in the web region under the cooling time of 30 s and the air pressure cooling condition of 12 bar. At the cooling rate up to 6°C/s, the microstructure is transformed to acicular ferrite and polygonal ferrite phase from Ferrite+Pearlite. But upper bainite phase was formed at a cooling rate of 30°C/s, and a small amount of martensite and lower bainite microstructures were observed at a cooling rate of 60°C/s and above. The hardness in the untreated sections, in the range of 106-120 HB, was increased to 195 HB at a cooling rate of 83 C/s in the web region of the HEA120 section. For a cooling rate of 23°C/s, the maximum compressive residual stresses of –352 MPa are measured in the crotch region of the HEB120. And for a cooling rate of 6°C/s, the maximum tensile residual stresses of 442 MPa were determined in the flange region of the HEA120 section.
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Authors and Affiliations

A. Işıkgül
1
ORCID: ORCID
H. Ahlatci
2
ORCID: ORCID
İ. Esen
3
ORCID: ORCID
Y. Türen
2
ORCID: ORCID
O. Yağız
2
ORCID: ORCID

  1. Karabük Iron Steel Industry Trade and Co. Inc., Research and Development Department, Karabük, Turkey
  2. Karabük University, Department of Metallurgy and Materials Engineering, Karabük, Turkey
  3. Karabük University, Department of Mechanical Engineering, Karabük, Turkey
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Abstract

Facing severely competitive global markets, managers of the modern transnational corporations must effectively integrate its intra-supply chain system to meet customers’ multiproduct demands with good quality items, minimum operating expenses, and in a timely delivery matter. Inspired by assisting current transnational firms to achieve the mission, this study builds a mathematical model to explore a multiproduct fabrication-shipment problem incorporating an accelerated rate and ensured product quality. A single machine production scheme under a common cycle policy and with random defects, rework, and an accelerated fabrication rate is considered. The speedy rate option is associated with extra setup and linear variable costs, which aims to cut short the common cycle time. Mathematical derivation is employed to find the long-run average system expense. The optimization method is used to jointly derive the decision for common length and delivery frequency per cycle for the problem. Numerical illustration is offered to confirm the applicability of the results and expose the individual/combined influences of diverse crucial system features on the problem, thus facilitate the intra-supply chain’s fabrication-shipment decision making.
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Authors and Affiliations

Yuan-Shyi Peter Chiu
1
Victoria Chiu
2
Hong-Dar Lin
1
Tiffany Chiu
3

  1. Faculty of Industrial Engineering & Management, Chaoyang University of Technology, Taichung City 413, Taiwan
  2. Faculty of Accounting, Finance and Law, State University of New York at Oswego, Oswego, NY 13126, USA
  3. Faculty of Anisfield School of Business, Ramapo College of New Jersey, Mahwah, NJ 07430, USA
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Abstract

In a corrosive environment with coupled dry-wet-sulfate action, concrete structures are susceptible to erosion by sulfate ions, which seriously affects the safe operating life. To forecast the operational lifetime of concrete below the influence of the dry-wet cycle and sulfate erosion environment, four different admixtures of polypropylene fiber: 0, 0.6, 0.9, and 1.2 kg/m 3, were incorporated into concrete specimens, and indoor accelerated tests were designed to observe the macroscopic and microscopic deterioration law analysis of concrete specimens; using the precept of damage mechanics, the damage of concrete under solubility cycle was established. The damage evolution equation of concrete under freeze-thaw cycles was established and the operational life of concrete was predicted. The results showed that the overall mass loss rate of concrete specimens increased with the number of tests, and the relative energetic modulo decreased with the number of tests; the pore change pattern, microstructure, and internal material composition of specimens under different working conditions were obtained by using NMR scanning technique, SEM electron microscope scanning technique and XRD physical phase analysis technique. The damage evolution equation shows that adding a certain amount of polypropylene fiber to concrete can improve the working life of concrete under dry and wet connected sulfate assault.
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Authors and Affiliations

Nan Nie
1
ORCID: ORCID

  1. Station Building Construction Department, China Railway Guangzhou Bureau Group Co., China
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Abstract

The work presents a structural and functional model of a distributed low level radio frequency (LLRF) control, diagnostic and telemetric system for a large industrial object. An example of system implementation is the European TESLA-XFEL accelerator. The free electron laser is expected to work in the VUV region now and in the range of X-rays in the future. The design of a system based on the FPGA circuits and multi-gigabit optical network is discussed. The system design approach is fully parametric. The major emphasis is put on the methods of the functional and hardware concentration to use fully both: a very big transmission capacity of the optical fiber telemetric channels and very big processing power of the latest series of DSP/PC enhanced and optical I/O equipped, FPGA chips. The subject of the work is the design of a universal, laboratory module of the LLRF sub-system. The current parameters of the system model, under the design, are presented. The considerations are shown on the background of the system application in the hostile industrial environment. The work is a digest of a few development threads of the hybrid, optoelectronic, telemetric networks (HOTN). In particular, the outline of construction theory of HOTN node was presented as well as the technology of complex, modular, multilayer HOTN system PCBs. The PCBs contain critical sub-systems of the node and the network. The presented exemplary sub-systems are: fast optical data transmission of 2.5 Gbit/s, 3.125 Gbit/s and 10 Gbit/s; fast A/C and C/A multichannel data conversion managed by FPGA chip (40 MHz, 65 MHz, 105 MHz), data and functionality concentration, integration of floating point calculations in the DSP units of FPGA circuit, using now discrete and next integrated PC chip with embedded OS; optical distributed timing system of phase reference; and 1GbEth video interface (over UTP or FX) for CCD telemetry and monitoring. The data and functions concentration in the HOTN node is necessary to make efficient use of the multigigabit optical fiber transmission and increasing the processing power of the FPGA/DSP/PC chips with optical I/O interfaces. The experiences with the development of the new generation of HOTN node based on the new technologies of data and functions concentration are extremely promising, because such systems are less expensive and require less labour.

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Authors and Affiliations

R.S. Romaniuk
K.T. Poźniak
T. Czarski
K. Czuba
W. Giergusiewicz
G. Kasprowicz
W. Koprek
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Abstract

Dynamic characteristics for three types of railgun constructions were simulated and measured in this work. The simplest construction is the iron-less (IL) railgun, while the two other ones (IC and ICPM) have an iron-core. The iron-core permanent magnet (ICPM) railgun additionally has permanent magnets. To compare their characteristics, similar dimensions of the rails and iron cores were adopted, and the same power supply system was used. Numerical magnetic field analyses and our analytical models have been used to determine the electromagnetic parameters. They were verified experimentally. The transient states of the railguns were studied with our field-circuit mathematical model, and their results were also verified by experiments.
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Authors and Affiliations

Paweł Piekielny
1
ORCID: ORCID
Bronisław Tomczuk
1
ORCID: ORCID
Andrzej Waindok
1
ORCID: ORCID

  1. Department of Electrical Engineering and Mechatronics, Opole University of Technology, Prószkowska 76 str., 45-758 Opole, Poland
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Abstract

Difficult geological and mining conditions as well as great stresses in the rock mass result in significant deformations of the rocks that surround the workings and also lead to the occurrence of tremors and rock bursts. Yielding steel arch support has been utilised in the face of hard coal extraction under difficult conditions for many years, both in Poland and abroad. A significant improvement in maintaining gallery working stability is achieved by increasing the yielding support load capacity and work through bolting; however, the use of rock bolts is often limited due to factors such as weak roof rock, significant rock mass fracturing, water accumulation, etc. This is why research and design efforts continue in order to increase yielding steel arch support resistance to both static and dynamic loads. Currently, the most commonly employed type of yielding steel arch support is a support system with frames constructed from overlapping steel arches coupled by shackles. The yield of the steel frame is accomplished by means of sliding joints constructed from sections of various profiles (e.g. V, TH or U-type), which slip after the friction force is exceeded; this force is primarily dependent on the type of shackles and the torque of the shackle screw nuts.

This article presents the static bench testing results of ŁP10/V36/4/A, ŁP10/V32/4/A and ŁP10/V29/4/A yielding steel arch support systems formed from S480W and S560W steel with increased mechanical properties. The tests were conducted using 2 and 3 shackles in the joint, which made it possible to compare the load capacities, work values and characteristics of various types of support. The following shackle screw torques were used for the tests:

• Md = 500 Nm – for shackles utilised in the support constructed from V32 and V36 sections.

• Md = 400 Nm – for shackles utilised in the support constructed from V29 sections.

The shackle screw torques used during the tests were greater compared to the currently utilised standard shackle screw torques within the range of Md = 350-450 Nm.

Dynamic testing of the sliding joints constructed from V32 section with 2 and 3 shackles was also performed. The SD32/36W shackles utilised during the tests were produced in the reinforced versions and manufactured using S480W steel.

Since comparative testing of a rock bolt-reinforced steel arch support system revealed that the bolts would undergo failure at the point of the support yield, a decision was made to investigate the character of the dynamics of this phenomenon. Consequently, this article also presents unique measurement results for top section acceleration values registered in the joints during the conduction of support tests at full scale.

Filming the yield in the joint using high-speed video and thermal cameras made it possible to register the dynamic characteristics of the joint heating process at the arch contact point as well as the mechanical sparks that accompanied it. Considering that these phenomena have thus far been poorly understood, recognising their significance is of great importance from the perspective of occupational safety under the conditions of an explosive atmosphere, especially in the light of the requirements of the new standard EN ISO 80079-36:2016, harmonised with the ATEX directive.

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Authors and Affiliations

Andrzej Pytlik

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