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Number of results: 12
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Abstract

Development of mineral deposits located at significant depth may be carried out by means of vertical shafts. Shaft sinking technology usually requires a number of works to be carried out, including the selection of appropriate excavating techniques adapted to geological and hydrological conditions, including natural hazards. The production technology and the machines used determine the level of sinking costs and execution period. The article discusses the excavating technologies currently used across the world. Then the assumptions, concept and construction of a new generation of shaft sinking system were presented. The proposed new solution of the system and the excavating technology allow for parallel execution of key processes related to winning, loading, transport and shaft wall-side lining, which significantly increases the progress of sinking. The shaft sinking system was created by scientists from AGH in cooperation with KOPEX – Przedsiębiorstwo Budowy Szybów S. A. and Instytut Techniki Górniczej KOMAG.

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Authors and Affiliations

Krzysztof Krauze
ORCID: ORCID
Łukasz Bołoz
ORCID: ORCID
Tomasz Wydro
ORCID: ORCID
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Abstract

Steel yielding arch support constructed of V profiles is commonly used to protect galleries and, in some cases, to reinforce or secure a shaft support. For this purpose, a closed, circular-shaped arch support is used, with arches overlapped by clamps that are typical for this type of construction. The support has high resistance to the impact of even (distributed over the entire surface of the support) load, however, as a result of significant deformation associated with a change in the radius of the curvatures, the support shows limited yielding capacity. This is due to the increase in resistance to slide on the locks, resulting from changes in the geometry of the ring caused by the rock mass. This article presents the results of research and analysis concerning the elements of the arch support with notches in arches. The research team tested the effect of the depth and location of the notches of the section’s flanges on the load impacting on the clamp’s bolts and the strength of the roof support. Moreover, the tests covered the influence of the number and location of clamps in a frictional joint on the change in the nature of work and yielding capacity. Finally, the research included both strength tests of the support’s elements, as well as strength analyses based on the finite element method.

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Authors and Affiliations

Marek Rotkegel
ORCID: ORCID
Łukasz Szot
Sławomir Fabich
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Abstract

Shaft steelwork is a component of critical infrastructure in underground mines. It connects the mining areas to the surface and enables the transport of personnel, equipment, and raw materials. Its failure or malfunction poses a threat to people and causes economic losses. Shaft steelwork is an exceptional engineering structure exposed to dynamic loads from large masses moving at high speeds and is subject to intensive deterioration resulting from corrosion and geological or mining-induced deformations. These issues cause shaft steelwork to be subject to high structural safety requirements, design oversizing, demanding maintenance procedures, and costly replacement of corroded members. The importance and unique working conditions of shaft steelwork create practical design and maintenance problems that are of interest to engineers and scientists. This paper reviews publications on the structural safety of rigid shaft steelwork and summarises the range of research from the detection of guide rail failures through the assessment of load effects and guide resistance, to the evaluation of structural reliability. The effects of guide rail failures on guiding forces, models of the conveyance-steelwork interaction, the load-carrying capacity of shaft steelwork under advanced corrosion, and the probabilistic assessment of structural reliability are presented. Significant advances in understanding the mechanical behaviour of shaft steelwork and assessing its properties have been reported. This review summarises the current state of research on shaft steelwork structural safety and highlights key future development directions.
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Authors and Affiliations

Przemysław Fiołek
1
ORCID: ORCID
Jacek Jakubowski
1
ORCID: ORCID

  1. AGH University of Krakow, Al. Mickiewicza 30, 30-059 Krakow, Poland
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Abstract

In this paper, the authors present a novel construction of an automatic balancing device applicable to balancing shafts working in a heavily polluted environment. The novelty of the presented system lies in the fact that its utilization requires no changes to be made in the already existing shafts. Also, the system is capable of working during the operation of the balanced shaft, so there is no need to stop it. The propulsion system is based on eddy current braking, therefore no wires need to be used in the device. During the development process of the system, three iterations of the device were created. Each iteration is presented, described, and discussed. The advantages and drawbacks of each version are pointed out and explained thoroughly. The correctness of the design was verified by the created devices that were assembled and fixed on shafts to prove the design assumptions.
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Bibliography

[1] J. Alsalaet. Dynamic Balancing and Shaft Alignment. College of Engineering – University of Basrah, Iraq, 2015.
[2] G.K. Grim, J.W. Haidler, and B.J. Mitchell. The Basics of Balancing. Balance Technology Inc., 2014.
[3] M. MacCamhaoil. Static and Dynamic Balancing of Rigid Rotors. Brüel & Kjær, 2016.
[4] R. Kelm, D. Pavelek, and W. Kelm. Rotor balancing tutorial. In: 45th Turbomachinery Symposium, pages 1–29, Huston, Texas, USA, Sept.12–15, 2016. doi: 10.21423/R1G59R.
[5] W.C. Foiles and P.E. Allaire. Single plane and multi-plane rotor balancing using only amplitude. In: 7th IFToMM International Conference on Rotor Dynamics, Vienna, Austria, Sept. 25–28, 2006.
[6] L. Li, S. Cao, J. Li, R. Nie, and L. Hou. Review of rotor balancing methods. Machines, 9(5):89, 2021. doi: 10.3390/machines9050089.
[7] Bendix Aviation Corp. Automatic Balancing of Rotating Bodies. Patent GB570170A, 1945.
[8] P. Żak. A survey of automatic balancing methods for shafts in motion. International Journal of Mechanical Engineering and Robotics Research, 9(4):559–564. doi: 10.18178/ijmerr.9.4.559-564.
[9] P. Loetzner, C.P. Hemingray, and C. Maas. Rotatable shaft balancing machine and method with automatic flexible shaft balancing equipment. Patent US20030024309A1, 2003.
[10] L. Capo and I. Goodbar. Device for the automatic static and dynamic balancing of rotating machinery. Patent GB679522A, 1952.
[11] G. Darrieus. Apparatus for automatic balancing of rotating bodies. Patent US2659243A, 1953.
[12] G. Darrieus. Device for automatic balancing of rotating machine parts. Patent US2778243A, 1957.
[13] J. Perdiart. System for automatically balancing a centrifuge in operation. Patent US4919646, 1990.
[14] O.A. Makarov, V.I. Nisenman, V.I. Pryadilov, and J.P. Tsimansky. Device for automatic balancing of grinding wheel. Patent US4905419, 1990.
[15] H. Wu, X. Pan, and H. Gao. Pneumatic liquid on-line automatic balancer of rotor. Patent US20140311281A1, 2014.
[16] P.C. Stein. Permanent automatic rotor balancer for shafts operating above critical speed. Patent US4117742A, 1978.
[17] W.R. Backer. Automatic balancing means. Patent GB957577A, 1962.
[18] K. Unno and K. Sugita. Automatic balancing apparatus for a rotating body. US3776065A, 1973.
[19] H. Kuwajima, H. Kita, H. Hashi, M. Miyamoto, Y. Ueno, T. Inagaki, and K. Matsuoka. Development of balanced-type high shock suspension for 0.85-in hard disk drive. IEEE Transactions on Magnetics, 42(2):255–260, 2006. doi: 10.1109/TMAG.2005.861736.
[20] Gao Jinji and Zhang Peng. Simulative study of automatic balancing of grinding wheel using a continuously-dripping liquid-injection balancing head. In: 2006 6th World Congress on Intelligent Control and Automation, pages 8002-8005, Dalian, China, 2006. doi: 10.1109/WCICA.2006.1713530.
[21] E. Lulay. Apparatus for balancing a rotary member. Patent US5676025A, 1997.
[22] M. Krygier, P. Żak, L. Podsędkowski, P. Wróblewski, and M. Podsędkowski. A novel autonomous balancing system for shafts in motion. 2022 20th International Conference on Mechatronics – Mechatronika (ME), pages 1-4, Pilsen, Czech Republic, 2022, doi: 10.1109/ME54704.2022.9983460.
[23] M. Krygier, P. Żak, and L. Podsedkowski. Numerical analysis of torques generated in a propulsion system using eddy currents phenomenon. 5th International Conference on Robotics Systems and Automation Engineering (RSAE) (RSAE 2023), April 20–22, 2023, online.
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Authors and Affiliations

Michał Krygier
ORCID: ORCID
Paweł Żak
1
ORCID: ORCID
Leszek Podsędkowski
1
ORCID: ORCID
Piotr Wróblewski
1
ORCID: ORCID
Maciej Podsędkowski
2
ORCID: ORCID

  1. Institute of Machine Tools and Production Engineering, Lodz University of Technology, Lodz, Poland
  2. Institute of Turbomachinery, Lodz University of Technology, Lodz, Poland
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Abstract

The iron ore mine owned by the state concern of Luossavaara – Kiirunavaara AB-LKAB state concern has several mining skip shaft hoists for drawing iron ore. Despite using modern systems to secure the travel of these hoists in line with the Swedish regulations, units intended for the emergency breaking of vessels must be used in the so-called free travel paths in the tower and in the shaft sump. The paper discusses the main requirements that, in accordance with the Swedish regulations as regards the operational use of mining shaft hoists, must be met by devices of this type and a solution was proposed for a structure design of the braking unit for the mining shaft hoist installed in the B-1 shaft in the Kiruna mine. The frictional braking system in the form of moving bumping beams was decided to be used in the said hoist, developed in the Cable Transport Department in the University of Science and Technology in Krakow. The action of moving bumping beams consists in these beams, placed at the beginning of free travel paths, not only braking the rushing hoist vessels but also (with the integrated units for vessel capture) performing the function of grips. They secure the vessels against falling down into the shaft after the finished braking process. The advantage of such a solution is that the structural elements: the guiding shank of the tower, the head of the vessel and the bumping beams, transfer many times lower values of dynamic forces at the time of the strike of the vessel against the moving bumping beams when compared with dynamic forces arising at the time of the hit of the vessel against the fixed bumping beams. In the process of designing moving bumping beams, braking simulation is an important stage conducted with a computer program developed in KTL AGH. This program enables the modelling of load-bearing and balance ropes as flexible elements with elastic and suppressing properties. The results of these simulations, especially in the scope of the achieved braking deceleration of the vessels, the values of braking distances and forces in the load-bearing ropes are crucial in confirming the correctness of the assumed concept of the emergency braking system. The braking units in the form of moving bumping beams have been executed by the Polish company Coal-Bud Sp. z o.o. and are now being integrated in the tower and in the shaft sump of the B-1 shaft of the Kiruna mine in Sweden.

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Authors and Affiliations

Tomasz Rokita
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Abstract

The rotating machines with overhung rotors form a broad class of devices used in many types of industry. For this kind of rotor machine in the paper, there is investigated an influence of dynamic and static unbalance of a rotor, parallel and angular misalignments of shafts, and inner anisotropy of rigid couplings on system dynamic responses. The considerations are performed through a hybrid structural model of the machine rotor-shaft system, consisting of continuous beam finite elements and discrete oscillators. Numerical calculations are carried out for parameters characterizing a heavy blower applied in the mining industry. The main goal of the research is to assess the sensitivity of the imperfections mentioned above on excitation severity of rotor-shaft lateral vibrations and motion stability of the machine in question.
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Bibliography

  1. K. Nandakumar and A. Chatterjee, “Nonlinear secondary whirl of an overhung rotor”, in Proc. R. Soc. A., vol. 466, pp. 283–301, 2010, doi: 10.1098/rspa.2009.0262.
  2.  O. Cakmak and K.Y. Sanliturk, “A dynamic model of an overhung rotor with ball bearings”, in Proc. Inst. Mech. Eng., Part K: J. Multi- body Dyn., vol. 255, no. 4, pp. 310–321, 2011, doi: 10.1177/1464419311408949.
  3.  Ch. Fu, X. Ren, Y. Yang, and W. Qin, “Dynamic response analysis of an overhung rotor with interval uncertainties”, Nonlinear Dyn., vol. 89, pp. 2115–2124, 2017, doi: 10.1007/s11071-017-3573-3.
  4.  E. Chipato, A.D. Shaw, and M.I. Friswell, “Frictional effects on the Nonlinear Dynamics, of an overhung rotor”, Commun. Nonlinear Sci. Numer. Simul., vol. 78, p. 104875, 2019.
  5.  ISO 1940/1, ”Balance Quality Requirements of Rigid Rotors”, International Organization for Standardization, 2003.
  6.  K.M. Al-Hussain and I. Redmond, “Dynamic response of two rotors connected by rigid mechanical coupling with parallel misalignment”, Sound Vib., vol. 249, no. 3, pp. 483–498, 2002.
  7.  K.M. Al-Hussain, “Dynamic stability of two rigid rotors connected by a flexible coupling with angular misalignment”, J. Sound Vib., vol. 266, no. 2, pp. 217–234, 2002.
  8.  A.W. Lees, “Misalignment in rigidly coupled rotors”, J. Sound Vib., vol. 305, pp. 261–271, 2007.
  9.  I. Redmond, “Study of a misaligned flexibly coupled shaft system having nonlinear bearings and cyclic coupling stiffness – Theoretical model and analysis”, J. Sound Vib., vol. 329, pp. 700–720, 2010.
  10.  J. Didier, J.-J. Sinou and B. Faverjon, “Study of the nonlinear dynamic response of a rotor system with faults and uncertainties”, J. Sound Vib., vol. 331, pp. 671–703, 2012.
  11.  P. Pennacchi, A. Vania, and S. Chatterton, “Nonlinear effects caused by coupling misalignment in rotors equipped with journal bearings”, Mech. Syst. Signal Process., no.30, pp. 306–322, 2012.
  12.  A. Muszyńska, Ch.T. Hatch, and D.E. Bently, “Dynamics of anisotropically supported rotors”, Int. J. Rotating Mach., vol. 3, no. 2, pp. 133–142, 1997.
  13.  J. Malta, “Investigation of anisotropic rotor with different shaft orientation”, Doctoral Thesis, Darmstadt University of Technology, Department of Machinery Construction, D 17, Darmstadt, 2009.
  14.  T. Szolc, P. Tauzowski, R. Stocki, and J. Knabel, ”Damage identification in vibrating rotor-shaft systems by efficient sampling approach”, Mech. Syst. Signal Process., vol. 23, pp. 1615–1633, 2009.
  15.  T. Szolc, “On the discrete-continuous modeling of rotor systems for the analysis of coupled lateral-torsional vibrations”, Int. J. Rotating Mach., vol. 6, no. 2, pp. 135–149, 2000.
  16.  T. Szolc, K. Falkowski, M. Henzel, and P. Kurnyta-Mazurek, “The determination of parameters for a design of the stable electro-dynamic passive magnetic support of a high-speed flexible rotor”, Bull. Pol. Acad. Sci. Tech. Sci., vol. 67, no. 1, pp. 91–105, 2019.
  17.  A. Pręgowska, R. Konowrocki, and T. Szolc, “On the semi-active control method for torsional vibrations in electro-mechanical systems by means of rotary actuators with a magneto-rheological fluid”, J. Theor. Appl. Mech., vol. 51, no. 4, pp. 979–992, 2013.
  18.  R. Lasota, R. Stocki, P. Tauzowski, and T. Szolc, ”Polynomial chaos expansion method in estimating probability distribution of rotor-shaft dynamic responses”, Bull. Pol. Acad. Sci. Tech. Sci., vol. 63, no. 1, pp. 413–422, 2015.
  19.  Y. Ma, Z. Liang, M. Chen, and J. Hong, “Interval analysis of rotor dynamic response with uncertain parameters”, J. Sound Vib., vol. 332, pp. 3869–3880, 2013.
  20.  Z. Qiu and X. Wang, “Parameter perturbation method for dynamic responses of structures with uncertain-but-bounded parameters based on interval analysis”, Int. J. Solids Struct., vol. 42, pp. 4958–4970, 2005.
  21.  Ch. Fu, Y. Xu, Y. Yang, K. Lu, F. Gu, and A. Ball, “Response analysis of an accelerating unbalanced rotating system with both random and interval variables”, J. Sound Vib., vol. 466, p. 115047, 2020. https://doi.org/10.1016/j.jsv.2019.115047.
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Authors and Affiliations

Tomasz Szolc
1
ORCID: ORCID
Robert Konowrocki
1
ORCID: ORCID

  1. Institute of Fundamental Technological Research of the Polish Academy of Sciences, ul. Pawińskiego 5B, 02-106 Warsaw, Poland
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Abstract

The aim of research was creation of a furnace for aluminum alloys smelting “in a liquid bath” in order to reduce metal loss. In the paper,

the author demonstrates the results of research on smelting of aluminum alloys in a shaft-reverberatory furnace designed by the author. It

has been shown that smelting aluminum alloy in a liquid bath was able to significantly reduce aluminum loss and that shaft-reverberatory

design provided high efficiency and productivity along with lower energy costs. Ensuring continuous operation of the liquid bath and

superheating chamber, which tapped alloy with the required texture, was achieved by means of the optimal design of partition between

them. The optimum section of the connecting channels between the liquid bath of smelting and the superheating chamber has been

theoretically substantiated and experimentally confirmed. The author proposed a workable shaft-reverberatory furnace for aluminum

alloys smelting, providing solid charge melting in a liquid bath.

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Authors and Affiliations

V. Grachev
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Abstract

Electro-dynamic passive magnetic bearings are now viewed as a feasible option when looking for support for high-speed rotors. Nevertheless, because of the skew-symmetrical visco-elastic properties of such bearings, they are prone to operational instability. In order to avoid this, the paper proposes the addition of external damping into the newly designed vibrating laboratory rotor-shaft system. This may be achieved by means of using simple passive dampers that would be found among the components of the electro-dynamic bearing housings along with magnetic dampers, which satisfy the operational principles of active magnetic bearings. Theoretical investigations are going to be conducted by means of a structural computer model of the rotor-shaft under construction, which will take into consideration its actual dimensions and material properties. The additional damping magnitudes required to stabilize the most sensitive lateral eigenmodes of the object under consideration have been determined by means of the Routh-Hurwitz stability criterion.

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Authors and Affiliations

T. Szolc
F. Falkowski
M. Henzel
P. Kurnyta-Mazurek
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Abstract

In this paper, the author derives theoretical formulae for calculating of squeezing forces. This report is the first one concerning the method of forming stepped shafts by longitudinal cold rolling. The formulae of the radial squeezing forces for the final passage of longitudinal rolling were calculated under the Huber hypothesis of plastic deformation and maximum shear stress.

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Authors and Affiliations

Marek Kowalik
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Abstract

This work presents an innovative shaft-lining solution which, in accordance with a patent of the Republic of Poland, allows successive, periodic leaching of excess rock salt migrating to the shaft opening. As is commonly known, all workings in rock salt strata are exposed to an increased convergence of sidewalls, making it very difficult to use shafts properly. Rocks migrating towards the shaft opening cause very high stress on the shaft liner. As a result, if the lining does not show substantial deformability, it fails. Lining failure due to insufficient deformability has been extensively described in the literature. Also, throughout the history of mining construction, a number of solutions have been proposed for different types of lining-deformability enhancement. For instance, the KGHM mining corporation applied a deformable steel lining – a solution used in the mining construction of galleries – along a 155-m-long section of the SW-4 shaft with diameters of 7,5 m that passes through a rock salt strata. At KGHM, the SW-4 shaft passes through a rock salt strata along a section of 155 m, in which a deformable enclosed steel lining was made. After several years, the convergence of shaft sidewalls stabilised at a rate of 0.5 mm/day. This enormous activity of the rock mass made it necessary to reconstruct the entire shaft section after only four years. According to further predictions, it will be necessary to reconstruct this section at least four times by 2045. This paper discusses in short form the underlying weaknesses of the technology in question.

As a solution to the problems mentioned above, the authors of this work present a very simple design of a shaft lining, called the tubing-aggregate lining, which utilises the leachability of salt rock massifs. The essential part of the lining is a layer of coarse aggregate set between the salt rock sidewall and the inner column of the tubing lining. One the one hand, coarse aggregate supports the salt rock sidewall and is highly deformable due to its compressibility, but on the other hand it allows water or low saturated brine to migrate and dissolve salt rock sidewalls.

This paper presents the first stage of works on this subject. Patent No. PL 223831 B had been granted before these works commenced.

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Authors and Affiliations

Paweł Kamiński
Piotr Czaja
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Abstract

Based on the analysis of the LIDAR terrain Digital Elevation Model (DEM), traces of opencast and underground mining of iron ore mining were located and classified. They occur in the zone of ore-bearing deposits outcropping on the north-eastern and north-western bounds of the Holy Cross Mountains. The DEM of an area covered by thirty-six (36) standard sheets of the Detailed Geological Map of Poland on a scale of 1:50,000 was thoroughly explored with remote sensing standards. Four types of ore recovery shafts with accompanying waste heaps were classified. The acquired data on the extent of former mining areas, covered with varying shafts and barren rock heaps could make a basis for distinguishing, according to historical data and in cooperation with archaeologists, the historical development stages of today’s steel industry. According to general knowledge, the iron industry in Europe instigate dates from the Roman times, in the Ist century BC to the IVth century AD, throughout the earlier and the late medieval times, up to the most recent the 1970ties. The usefulness of the LIDAR method has already been amazingly confirmed in archaeological researches worldwide. Many discoveries of ling forgotten, even large entities resulting from human activities in Asia and Central America especially were discovered owed to the LIDAR DEM. Also, traces of human settlements from various historical periods were discovered that way in Poland. The applicability of DEM based on LIDAR data is, in geological studies of surficial geodynamic processes and in geological mapping in Poland, rather contested.

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Authors and Affiliations

Zygmunt Heliasz
Stanisław Ostaficzuk
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Abstract

The use of subway tunnel engineering technology has become more professional and refined with the growth of society and the advancement of science and technology. The initial construction process of a subway tunnel shield is the most critical part of the entire engineering system. Shield launching period construction is the most prone to accidents in the shield construction process, directly related to the smooth through the shield tunnel. The line 1 of Ho Chi Minh (HCM) Metro is the first subway line, the full length of 19.7 km, the underground road length of 2.6 km from km 0 + 615 to km 2 + 360, from Ben Thanh market, and then through the Sai Gon river and 14 station (including 3 underground stations and 11 elevated stations), reach Suoi Tien park and is located in Long Binh area station, underground building blocks including Ben Thanh market station to Opera House station interval, Opera House station, Opera House station to Ba Son station interval. This paper selects Shield launching period of Opera House station to Ba Son shaft interval as an example, analyze the key construction technology, construction control parameters and launching considerations of shield machine.
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Authors and Affiliations

Xuan Loi Nguyen
1
Li Wu
1
ORCID: ORCID
Khanh Tung Nguyen
2
Quang Anh Bui
2
Huy Hoang Nguen
2
Hoang Phuong Luu
3

  1. Faculty of Engineering, China University of Geosciences (Wuhan), No. 388 Lumo Road, Wuhan 430074, Hubei, P.R. China
  2. FECON UCC., JSC, 19th floors, CEO Tower, Lot HH2-1, Me Tri Ha Urban Area, Pham Hung road, Me Triward, Nam Tu Liem district, Hanoi city, Vietnam
  3. FECON., JSC, 14th floors, CEO Tower, Lot HH2-1, Me Tri Ha Urban Area, Pham Hung road, Me Tri ward, Nam Tu Liem district, Hanoi city, Vietnam

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