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Number of results: 11
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Abstract

Lean is one of the systematic approach to achieve higher value for organizations through

eliminate non-value-added activities. It is an integrated set of tools, techniques, and principles

designed to optimize cost, quality and delivery while improving safety. In Vietnam,

industry waste management and treatment has become serious issue. The aim of this research

is to present the effective of Lean application for industrial wastes collecting and

delivery improvement. Through a case study, this paper showed the way of Lean tools and

principles applied for wastes management and treatment such as Value Stream Mapping,

Pull system, Visual Control, and Andon to get benefit on both economic and environment.

In addition, the results introduced a good experience for enterprises in Vietnam and other

countries have similar conditions to Vietnam in cost saving and sustainable development in

waste management.

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Authors and Affiliations

Nguyen Dat Minh
Nguyen Danh Nguyen
Phan Kien Cuong
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Abstract

Having increasingly tightened geological and mining conditions in which the extraction of copper ore deposits in Poland is conducted, ensuring effective and safe mining is presently becoming a key task and a significant challenge for mine operators, mainly in the field of ground support systems being the equivalent for the new geological/mining conditions. As one may expect, these conditions shall be characterized by higher values of the primary stress tensor elements as well as the lower deformability and higher strength of the rock mass surrounding the copper ore body. T his means that in the near future, the rock bursts problem will become one of the most important issues deciding on the economy and safety within the newly developed mining areas. T herefore developing a novel effective ductile ground support systems which could be able to control the rock mass movement in squeezing and burst-prone rock conditions is recommended. T his type of requirement may fulfil only ductile or, in other words, the kinetic energy-absorbing systems, which permit slowing down a movement of violently ejected rock blocks. T his paper’s objective is to present the idea of the development of a new type of an effective and low cost ductile resin anchored rockbolt system with smooth and of the square cross-section steel rod is formed in coil shape of different pitch. T he developed bolt prototypes have been tested underground in the G-11 section of the Rudna mine. Results of the pull-out tests, involving different bolts’ shapes and different sliding materials set on the rockbolts’ rods, have proved those bolts’ efficiency as an element of the ductile support system.

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Authors and Affiliations

Witold Pytel
Piotr Mertuszka
Krzysztof Szeptun
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Abstract

The fate of European citizens living in the United Kingdom was a key issue linked with Britain’s departure from the European Union. Official statistics show that some outflow has taken place, but it was no Brexodus. This article investigates Brexit’s impact within a theoretical (push–pull) framework using a survey of long-term Polish migrants in the UK (CAPI, N = 472, conducted in 2018). Our results show that the perception of Brexit as a factor discouraging migrants from staying in the UK was limited. Still, those with experience of living in other countries, those remitting to Poland, and those on welfare benefits, were more likely to find Brexit discouraging. However, many claimed that the referendum nudged them towards extending their stay instead of shortening it. In general, when asked about what encourages/discourages them from staying in the UK, the respondents mainly chose factors related to the job market. Therefore, we argue, in line with Kilkey and Ryan (2020), that the referendum was an unsettling event – but, considering the strong economic incentives for Polish migrants to stay in the UK, we can expect Brexit to have a limited influence on any further outflows of migrants, as long as Britain’s economic situation does not deteriorate.

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Authors and Affiliations

Barbara Jancewicz
Weronika Kloc-Nowak
ORCID: ORCID
Dominika Pszczółkowska
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Abstract

The presented problem consists in optimizing the pulling force of the luffing jib tower cranes, in order to reduce power and save energy by determining reasonable geometrical parameters such as placement of pulley assemblies, position of jib pin, and jib length. To determine the optimal parameters, a mechanical model was developed to calculate the pulling force of the research object. Then, the Taguchi method and Minitab software were applied to evaluate the influence of the parameters. The objective function was the minimum pulling force of the luffing jib. The calculation results show that the position of the pulley assembly used to pull the jib is the most influential factor on the objective function accounting for 81.15%, the less significant factors are the jib length, the pin position of the jib, and the pulley assembly that changes the direction of the load lifting cable. The result of the test presented in the article allowed for determining the rational parameters, and the optimal position of the pulley assemblies on the top of the crane. In the case of the pulley assembly located at the top of the crane, one obtains the optimal height of the crane head H≈0.4 L c.
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Bibliography

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Authors and Affiliations

Truong Giang Duong
1
ORCID: ORCID

  1. Faculty of Mechanical Engineering, Hanoi University of Civil Engineering, Hanoi, Vietnam
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Abstract

This article presents an experimental investigation of polarization pulling based on stimulated Raman scattering induced by a continuous, fully polarized pump wave in an optical fibre. By means of probe wave states of polarization aggregation, degree of polarization and gain analysis, an assessment of all-optical polarization control, repolarization and amplification in a standard single mode fibre in depleted pump regime is presented. Polarization pulling is proved to be dependent on fibre length, pump power, and pump state of polarization, with respect to pump depletion effect, acting oppositely to the polarization pulling effect. Authors evaluate results aiming to obtain a configuration of stimulated Raman scattering parameters, which allows for the most effective polarization pulling, with respect to statistical stability of the process measured by standard deviation of polarization degree and polarization-dependent gain of the probe wave. The highest polarization attraction efficiency was obtained for 15 km, 0.97 W and the horizontal polarization state of the pump wave.
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Authors and Affiliations

Robert K. Cybulski
1 2
ORCID: ORCID
Krzysztof Perlicki
2
ORCID: ORCID

  1. Dawis IT Sp. z o.o., ul. Staszica 1, 05-800 Pruszków, Poland
  2. Institute of Telecommunications, Warsaw University of Technology, ul. Nowowiejska 15/19, 00-665 Warsaw, Poland
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Abstract

The aim of this paper is to evaluate the fatigue resistance of austenitic nodular cast iron and to compare it with other types of nodular cast irons. The austenitic nodular cast iron, used for the experiments, was alloyed by 13% nickel and 7% manganese (EN-GJSA-XNiMn13-7) to obtain an austenitic matrix. The microstructure was studied using light metallographic microscopy. Mechanical properties were investigated by tensile test, impact bending test and Brinell hardness test. Fatigue tests were carried out at sinusoidal cyclic push-pull loading at ambient temperature. The results of fatigue tests were compared with the fatigue properties of ferrite-pearlitic nodular cast iron and pearlite-ferritic nodular cast iron. Experimental results show that NiMn-type of austenitic nodular cast iron has lower tensile strength and hardness, but higher elongation and absorbed energy than the compared types of nodular cast iron. However, austenitic nodular cast iron has lower fatigue limit.
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Authors and Affiliations

A. Vaško
1
ORCID: ORCID
M. Uhríčik
1
ORCID: ORCID
V. Kaňa
2
ORCID: ORCID

  1. University of Žilina, Faculty of Mechanical Engineering, Department of Materials Engineering, Žilina, Slovakia
  2. Brno University of Technology, Faculty of Mechanical Engineering, Department of Foundry Engineering, Brno, Czech Republic
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Abstract

The article discusses results of pull-off adhesion strength tests on poly-p- phenylene benzobisoxazole (PBO) mesh bonded to fir timber beams using epoxy resin. The tests were performed in accordance with the PN-EN 1542 standard. Timber elements reinforced with PBO fibres were subjected to pull-off tests to measure the adhesive strength of the mesh to the beams.The factors occurring during the test were also characterized, which may affect its results such as the method of application of the tearing force, selection of epoxy glue, surface preparation of the tested elements, occurrence of material defects in the wood and types of substrate destruction.The experimental data show that failure of the timber layer was not observed in all the specimens tested.

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Authors and Affiliations

P.K. Sokołowski
P.G. Kossakowski
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Abstract

Resilient under sleeper pads (USPs) are vibration isolators used in the ballasted track structure to improve the dynamic performance of the track, reduce vibrations and protect the ballast layer. Being permanently connected with the rail supports (sleepers or turnout bearers), the pads must exhibit a proper value of the pull-off strength, which ensures that they do not separate from the supports while being transported to the construction site or during many years of exploitation. This study focuses on the experimental determination of the pull-off strength of USPs attached to full scale prestressed concrete sleepers. Three variants are tested: two pads equipped with different anchor layers attached to the sleepers in the production plant and one pad glued to the sleeper in the laboratory. Some of the tested USPs are made of recycled styrene-butadiene rubber (SBR). An important part of the work is specification of the requirements for the pull-off strength of USPs, as well as the requirements for sleepers and turnout bearers equipped with resilient pads.
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Authors and Affiliations

Cezary Kraskiewicz
1
ORCID: ORCID
Artur Zbiciak
1
ORCID: ORCID
Henryk Zobel
1
ORCID: ORCID
Anna Al Sabouni-Zawadzka
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw
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Abstract

Under sleeper pads (USPs) are resilient elements used in the ballasted track structures to improve dynamic behaviour of the track, reduce vibration and protect the ballast against fast degradation. As the elements permanently connected to the sleepers or turnout bearers, the pads must have an appropriate level of pull-off strength, so that they do not separate from the rail support (here: sleeper) during their transportation to the construction site or during many years of operation. In this paper, results of pull-off tests performed on four selected USP samples are presented: three samples made of SBR (styrene-butadiene rubber) granulate and one made of polyurethane. Moreover, details of the pad’s attachment to the rail support are discussed, and the requirements for the USP properties are specified, focusing on the pull-off strength determined after the weather resistance test. It is shown that only two out of four considered USP samples fulfilled the requirements specified by the authors.
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Authors and Affiliations

Cezary Kraśkiewicz
1
ORCID: ORCID
Artur Zbiciak
1
ORCID: ORCID
Jarosław Medyński
1
ORCID: ORCID
Anna Al Sabouni-Zawadzka
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw, Poland
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Abstract

Fe-C-Cr-Nb alloy steel surfacing layers with different contents of C and Cr were prepared on 45 steel base metal by selfshielded flux-cored wires with distinct amounts of high carbon chromium iron addition and melt arc surfacing. The composition and microstructure changes of the surfacing layer were tested and analyzed. The surfacing test plate was processed into a pulling specimen, and the bonding strength between the surfacing layer and the 45 steel base metal was tested with a self-designed pulling test method. The fracture location of the pulling specimen and fracture characteristics were observed by a metallurgical microscope and a scanning electron microscope. The result shows that with the increase of the amount of high carbon chromium iron added to flux-cored welding wire, the content of C and Cr in the surfacing layer increases, and the NbC hard phase disperses. The microstructure of the steel matrix changes from mixed martensite + residual austenite to high carbon martensite + residual austenite, and then independent austenite appears. The hardness of the surfacing layer first increases and then decreases. The bonding strength between the surfacing alloy and the 45 steel base metal first decreases and then increases, and the fracture location is at the bottom of the surfacing layer or the fusion zone with mostly quasi-cleavage characteristics. When the additional amount of high carbon chromium iron reaches 13%, thee pulling specimen exhibits significant deformation with the highest bonding strength, and the fracture is close to the fusion line, where there are numerous tearing edges and shallow dimples.
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Authors and Affiliations

Fei Huang
1

  1. High Speed Railway Comprehensive Technical College, Jilin Railway Technology College, Jilin, 132299, China
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Abstract

To study the influence of structural features of phthalocyanine (Pc) derivatives on their physico-chemical properties in bulk and thin films, 23 new phthalocyanines with different quantity and ratio of donor (alkyloxy-groups, in fragment “A”) and acceptor (Cl-, in fragment “B”) substituents in one molecule of the A3B, ABAB and AABB types with varied length of alkyloxy-substituents and their metal complexes were designed and synthesized. A comparative analysis of spectral, mesomorphic and photoelectric properties of these mix-substituted phthalocyanines of a “push–pull” type was performed. It was shown that non-peripheral substitution by alkyloxy-fragments in hetero-substituted Pcs (similar to homo-substituted Pc) leads to red-shifting of the Q-band into near-IR region. The intensity of photoluminescence, position of peaks and their splitting are strongly connected with chemical structure of Pcs and the type of solvent. In contrast to non-mesogenic octyloxy-Pc (A4) having alkyloxy-substituents in non-peripheral positions, 22 of 23 synthesized compounds possess columnar mesomorphism. The change of donor–acceptor ratio can influence the type of mesophase. A new approach to the creation of materials for optoelectronics is proposed and implemented, which includes design of compounds possessing vitrification from mesophase with maintenance of a columnar order, absorption in the near IR-region of the spectrum and good performance electrophysical characteristics simultaneously.

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Authors and Affiliations

N.V. Usol’tseva
A.I. Smirnova
A.V. Kazak
N.I. Giricheva
N.E. Galanin
G.P. Shaposhnikov
V.V. Bodnarchuk
S.V. Yablonskii

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