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Abstract

The paper presents the full transient, two-dimensional finite volume method numerical calculations of the classical involute scroll compressor geometry. The purpose of the study was to develop and evaluate an adaptable implementation of numerical fluid mechanics and thermodynamics modeling procedure with a mesh deformation. The methodology consisting in the compression chamber geometry preparation, mesh generation and governing equations solving was described. The evaluation was carried by simulating an adiabatic compression process and the results were compared with the theoretical zero-dimensional model and the existing research concerning the scroll chamber computational fluid dynamics modeling. It has been shown that the proposed modeling routine results in good accuracy for the scroll compressors study applications.

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Authors and Affiliations

Józef Rak
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Abstract

Steel Mesh-Reinforced Cementitious Composites (SMRCC) (traditionally known as ferrocement) have been in existence for few decades, but have some limitations set on element thickness and number of reinforcing mesh layers and the resulting deflection ductility. Therefore, the author has made an attempt to explore whether deflection ductility will improve in mesh-reinforced cementitious composites (25 mm thick) if discontinuous fibres are added to slab elements. For this purpose, thin slab elements of dimensions 700 mm (length) × 200 mm (width) × 25 mm (thickness) were cast and subjected to four point bending tests. Based on the flexural tests conducted on SMRCC (Control Slab Elements, cast with Steel Mesh Volume of reinforcement, MVr = 0.78, 0.94, and 1.23%) and Hybrid Mesh-and-Fibre-Reinforced Cement Based Composite (HMFRCBC) (Test Slab Elements, combining MVr = 0.78, 0.94 and 1.23% and Polyolefin Fibre Volume fraction, PO-FVf = 0.5‒2.5% of volume of specimens, with 0.5% interval), load-deflection and the deflection ductility index were analyzed. From the flexural load-deflection curves it has been observed that HMFRCBC slabs demonstrate higher flexural load-carrying capacity and deflection ductility when compared to SMRCC slabs. This study shows that higher the polyolefin fibre volume fraction (PO-FVf) from 0.5 to 2.5% (with a 0.5% interval) in HMFRCBC slabs, the higher the flexural deflection ductility. The Deflection Ductility Index (DDI) of HMFRCBC (with 5 layers of mesh and PO-FVf = 2.5%) is 4.5 times that of SMRCC. This study recommends that HMFRCBC can be used as an innovative construction material due to its higher flexural ductility characteristics.

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Authors and Affiliations

P.B. Sakthivel
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Abstract

Machines utilising renewable energy constantly undergo research aimed at raising their efficiency. One of them is a Savonius wind turbine, where scientists propose adjustments to improve its aerodynamic properties. At present, their assessment is usually performed by means of transient computational fluid dynamics simulations with two- or threedimensional models. In this paper, the overset (chimera) mesh approach was applied to investigate the performance of a Savonius wind turbine equipped with deformable blades. They were continuously deformed during rotation by a dedicated mechanism to increase a positive torque of the advancing blade, and meanwhile, decrease a negative torque of the returning blade. A quasi-two-dimensional model with a two-way fluid-structure interaction method was applied, where the structural solver determined blade deflection caused by the predefined deformation mechanism and aerodynamic loads, whereas the coupled computational fluid dynamics solver determined the transient flow. The deformable blades rotor performance was calculated and compared with a conventional rigid Savonius turbine, both simulated using the overset mesh approach. The average value of the power coefficient achieved a 55% rise in the case of deformable blades turbine. Additionally, to validate the overset method, its results were compared with the classical sliding mesh method for a conventional rigid rotor.
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Bibliography

[1] Akwa J.V., Vielmo H.A., Petry A.P.: A review on the performance of Savonius wind turbines. Renew. Sust. Energ. Rev. 16(2012), 5, 3054–3064.
[2] Masdari M., Tahani M., Naderi M.H., Babayan N.: Optimization of airfoil Based Savonius wind turbine using coupled discrete vortex method and salp swarm algorithm. J. Clean. Prod. 222(2019), 47–56.
[3] Alom N., Saha U.K..: Influence of blade profiles on Savonius rotor performance: Numerical simulation and experimental validation. Energ. Convers. Manage. 186(2019), 267–277.
[4] Zemamou M., Aggour M., Toumi A.: Review of savonius wind turbine design and performance. Energy Proced. 141(2017), 383–388.
[5] Tartuferi M., D’Alessandro V., Montelpare S., Ricci R.: Enhancement of savonius wind rotor aerodynamic performance: A computational study of new blade shapes and curtain systems. Energy 79(2015), 371–384.
[6] Mauro S., Brusca S., Lanzafame R., Messina M.: CFD modeling of a ducted Savonius wind turbine for the evaluation of the blockage effects on rotor performance. Renew. Energ. 141(2019), 28–39.
[7] Sobczak K., Obidowski D., Reorowicz P., Marchewka E.: Numerical investigations of the savonius turbine with deformable blades. Energies 13(2020), 14, 3717.
[8] Obidowski D., Sobczak K., Jozwik K., Reorowicz P.: Vertical Axis Wind Turbine with a Variable Geometry of Blades. European Patent Application 19199085.2, 24 Sept. 2019.
[9] Kamoji M.A., Kedare S.B., Prabhu S.V..: Experimental investigations on single stage modified Savonius rotor. Appl. Energ. 86(2009), 7-8, 1064–1073.
[10] Lipian M., Czapski P., Obidowski D.: Fluid-structure interaction numerical analysis of a small, urban wind turbine blade. Energies 13(2020), 7, 1–15.
[11] Marzec Ł., Bulinski Z., Krysinski T.: Fluid structure interaction analysis of the operating Savonius wind turbine. Renew. Energ. 164(2021), 272–284.
[12] Chan C.M., Bai H.L., He D.Q.: Blade shape optimization of the Savonius wind turbine using a genetic algorithm. Appl. Energ. 213(2018), 148–157.
[13] Saeed H.A.H., Elmekawy A.M.N., Kassab S.Z.: Numerical study of improving Savonius turbine power coefficient by various blade shapes. Alexandria Eng. J. 58(2019), 2, 429–441.
[14] Mohamed M.H., Janiga G., Pap E., Thcvenin D.: Optimization of Savonius turbines using an obstacle shielding the returning blade. Renew. Energ. 35(2010), 11, 2618–2626.
[15] Kacprzak K., Liskiewicz G., Sobczak K.: Numerical investigation of conventional and modified Savonius wind turbines. Renew. Energ. 60(2013), 578–585.
[16] ANSYS Inc.: ANSYS Fluent 20.2 User’s Guide. ANSYS Inc., Canonsburg, 2020.
[17] ANSYS Inc.: https://www.ansys.com/. ANSYS Inc., Canonsburg, 2020.
[18] Menter F.R., Langtry R., Völker S, Huang P.G.: Transition modelling for general purpose CFD codes. In: Proc. ERCOFTAC Int. Symp. on Engineering Turbulence Modelling and Measurements 6; ETMM6, Sardinia, 23-25 May 2005, 31–48.
[19] Kerikous E., Thévenin D.: Optimal shape of thick blades for a hydraulic Savonius turbine. Renew. Energ. 134(2019), 629–638.
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Authors and Affiliations

Emil Marchewka
1
Krzysztof Sobczak
1
Piotr Reorowicz
1
Damian Stanisław Obidowski
1
Krzysztof Jóźwik
1

  1. Lodz University of Technology, Institute of Turbomachinery, Wólczanska 219/223, 90-924 Łódz, Poland
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Abstract

This study aims to evaluate the efficiency of strengthening reinforced concrete beams using some valid strengthening materials and techniques. Using concrete layer, reinforced concrete layer and steel plates are investigated in this research. Experiments on strengthening beam samples of dimensions 100x150x1100 mm are performed. Samples are divided in to three groups. Group “A” is strengthened using 2 cm thickness concrete layer only (two types). Group “B” is strengthened using 2 cm thickness concrete layer reinforced with meshes (steel and plastic). Group “C” is strengthened using steel plates. The initial cracking load, ultimate load and crack pattern of tested beams are illustrated. The experimental results show that for group A and B, the ultimate strength, stiffness, ductility, and failure mode of RC beams, with the same thickness strengthening layer applied, will be affected by the mesh type, type of concrete layer. While for group C, these parameters affected by the fixation technique and adhesion type.

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Authors and Affiliations

Alaa A. Bashandy
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Abstract

For many years, a digital waveguide model is being used for sound propagation in the modeling of the vocal tract with the structured and uniform mesh of scattering junctions connected by same delay lines. There are many varieties in the formation and layouts of the mesh grid called topologies. Current novel work has been dedicated to the mesh of two-dimensional digital waveguide models of sound propagation in the vocal tract with the structured and non-uniform rectilinear grid in orientation. In this work, there are two types of delay lines: one is called a smaller-delay line and other is called a larger-delay line. The larger-delay lines are the double of the smaller delay lines. The scheme of using the combination of both smaller- and larger-delay lines generates the non-uniform rectilinear two-dimensional waveguide mesh. The advantage of this approach is the ability to get a transfer function without fractional delay. This eliminates the need to get interpolation for the approximation of fractional delay and give efficient simulation for sound wave propagation in the two-dimensional waveguide modeling of the vocal tract. The simulation has been performed by considering the vowels /ɔ/, /a/, /i/ and /u/ in this work. By keeping the same sampling frequency, the standard two-dimensional waveguide model with uniform mesh is considered as our benchmark model. The results and efficiency of the proposed model have compared with our benchmark model.

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Authors and Affiliations

Tahir Mushtaq Qureshi
Khalid Saifullah Syed
Asim Zafar
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Abstract

Umbilical hernia is one of the most common problems in young calves. This problem occurs in dairy sector as well as in the local farmers. Present study was conducted to compare outcomes of four different techniques of herniorrhaphy. Twenty four young calves (n=24) were divided in 4 groups (A, B, C, and D) which underwent four different surgical techniques. Group A underwent vicryl plus suture material and pants-over-west technique, Group B underwent mesh application with Dexon suture material by using simple interrupted suture pattern, Group C underwent closed method with Nylon No. 3 suture material by using vertical mattress suture pattern and Group D underwent clamp application method with Silk No. 2 suture material by using simple interrupted suture pattern. The result showed that mesh application method was comparatively better with respect to feed intake, body weight gain and healing time. There was no reoccurrence with non-significant hematological changes (p≤0.05). It is concluded that mesh application method is safer than other three techniques and there are no systemic effects of this surgical intervention on calves’ health.
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Bibliography


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Authors and Affiliations

A. Fatima
1
M. Arif Khan
1
S. Aslam
1
K. Ashraf
2
A. Khalid Mahmood
1
M. Asif
1
S. Shah
1
N. Hussain
1

  1. Department of Veterinary Surgery and Pet Sciences, University of Veterinary and Animal Sciences, Out fall road 54000, Lahore-Pakistan
  2. Department of Parasitology, University of Veterinary and Animal Sciences, Out fall road 54000, Lahore-Pakistan
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Abstract

In dentistry, 3D intraoral scanners (IOSs) are gaining increasing popularity in the production of dental prostheses. However, the quality of an IOS in terms of resolution remains the determining factor of choice for the practitioner; a high resolution is a quality parameter that can reduce error in the production chain. To the best of our knowledge, the evaluation of IOS resolution is not clearly established in the literature. This study provides a simple assessment of resolution of an IOS by measuring a reference sample and highlights various factors that may influence the resolution. A ceramic tip was prepared to create a very thin object with an edge smaller than the current resolution stated by the company. The sample was scanned with microCT (micro-computed tomography) and an IOS. The resulting meshes were compared. In the mesh obtained with the IOS, the distance between two planes on the edge was approximately 100 micrometers, and that obtained with microtomography was 25 micrometers. The curvature values were 27.46 (standard deviation – SD) 14.71) μm -1 and 5.18 (SD 1.16) μm -1 for microCT and IOS, respectively. These results show a clear loss of information for objects that are smaller than 100 μm. As there is no normalized procedure to evaluate resolution of IOSs, the method that we have developed can provide a positive parameter for control of IOSs performance by practitioners.
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Authors and Affiliations

Alban Desoutter
1
Gérard Subsol
2
Eric Fargier
3
Alexandre Sorgius
3
Hervé Tassery
1
Michel Fages
1
Frédéric Cuisinier
1

  1. Univ. Montpellier, 163 rue Auguste Broussonnet, 34090 Montpellier, France
  2. Laboratory of Computer Science, Robotics and Microelectronics of Montpellier, 161 Rue Ada, 34095 Montpellier, France
  3. Laboratoire National de Métrologie et d’Essais, 1 Rue Gaston Boissier, 75724 Paris Cedex 15, France
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Abstract

The paper presents an approach of numerical modelling of alloy solidification in permanent mold and transient heat transport between the casting and the mold in two-dimensional space. The gap of time-dependent width called "air gap", filled with heat conducting gaseous medium is included in the model. The coefficient of thermal conductivity of the gas filling the space between the casting and the mold is small enough to introduce significant thermal resistance into the heat transport process. The mathematical model of heat transport is based on the partial differential equation of heat conduction written independently for the solidifying region and the mold. Appropriate solidification model based on the latent heat of solidification is also included in the mathematical description. These equations are supplemented by appropriate initial and boundary conditions. The formation process of air gap depends on the thermal deformations of the mold and the casting. The numerical model is based on the finite element method (FEM) with independent spatial discretization of interacting regions. It results in multi-mesh problem because the considered regions are disconnected.

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Authors and Affiliations

T. Skrzypczak
L. Sowa
E. Węgrzyn-Skrzypczak
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Abstract

Th is report provides a concise overview of the rendering and utilization of three-dimensional models in the fi eld of anatomy. Anatomical three-dimensional virtual models are widely used for educational purposes, preoperative planning, and surgical simulations because they simply allow for interactive three-dimensional navigation across the human organs or entire body. Virtual threedimensional models have been recently fabricated as accurate replicas of the anatomical structures thanks to advances in rapid prototyping technology.

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Authors and Affiliations

Janusz Skrzat
Matthew J. Zdilla
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Abstract

The techniques of photogrammetric reconstruction were compared to the laser scanning in the article. The different conditions and constraints were introduced for reconstructed images, e.g. different materials, lighting condition, camera resolution, number of images in the sequence or using a-pripori calibration. The authors compare the results of surface reconstruction using software tools avaliable for photogrammetric reconstruction. The analysis is preformed for the selected objects with regard to laserscanned models or mathematical models.

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Authors and Affiliations

Krzysztof Skabek
Agnieszka Tomaka
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Abstract

The article presents experiments in realistic modelling of facial expressions using volume morphing. The experiments use a variable number of points and face features. As the results are shown meshes deviations (between goal mesh and morphed shape). Experiments have shown that it is impossible to carry out a fully realistic morphing based on existing software. At the same time, even imperfect morphing allows you to show the expected emotional facial expression.

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Authors and Affiliations

Przemysław Kowalski
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Abstract

The Bluetooth Low Energy (BLE) MESH network technology gains popularity in low duty IoT systems. Its advantage is a low energy consumption that enables long lifetime of IoT systems. The paper proposes and evaluates new MRT management methods, i.e. exact and heuristic, that improves energy efficiency of BLE MESH network by minimizing the number of active relay nodes. The performed experiments confirm efficiency of the MRT methods resulting in significantly lower energy consumption of BLE MESH network.

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Authors and Affiliations

Andrzej Bęben
Andrzej Bąk
Maciej Sosnowski
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Abstract

The subject of the article is the design and practical implementation of the wireless mesh network. IQRF radio modules were used for the network design. The IQRF® technique has enabled the construction of a mesh network with the possibility of reconfiguration. The theoretical part contains a description of the IQRF® hardware solutions used. The practical scope includes the design part, where the configuration of the radio modules was carried out and the parameters of the radio network were set to allow its implementation in various topologies. Then, a wireless network consisting of 10 IQRF modules was launched in the P3 building of the Opole University of Technology. At this stage, configured radio modules were placed in selected rooms on all five floors of the building in order to carry out tests of the radio network constructed in this way. The tests included measuring the packet transmission delay time as well as the received signal strength. Research was carried out for several network topologies.

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Authors and Affiliations

Sławomir Pluta
Patryk Roszkowski
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Abstract

Thermally induced free vibration of sandwich beams with porous functionally graded material core embedded between two isotropic face sheets is investigated in this paper. The core, in which the porosity phase is evenly or unevenly distributed, has mechanical properties varying continuously along with the thickness according to the power-law distribution. Effects of shear deformation on the vibration behavior are taken into account based on both third-order and quasi-3D beam theories. Three typical temperature distributions, which are uniform, linear, and nonlinear temperature rises, are supposed. A mesh-free approach based on point interpolation technique and polynomial basis is utilized to solve the governing equations of motion. Examples for specific cases are given, and their results are compared with predictions available in the literature to validate the approach. Comprehensive studies are carried out to examine the effects of the beam theories, porosity distributions, porosity volume fraction, temperature rises, temperature change, span-to-height ratio, different boundary conditions, layer thickness ratio, volume fraction index on the vibration characteristics of the beam.
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Bibliography

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Authors and Affiliations

Tran Quang Hung
1
Tran Minh Tu
2
ORCID: ORCID
Do Minh Duc
1

  1. Faculty of Civil Engineering, The University of Da Nang - University of Science and Technology, Da Nang, Vietnam
  2. Hanoi University of Civil Engineering, Hanoi, Vietnam
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Abstract

This paper presents the results of laboratory testing and Finite Element Method (FEM) modelling of high-strength double-twisted steel hexagonal wire mesh used for constructing gabion cages, slope protection systems, rockfall protection barriers. Gabion cages, filled with soil (usually rock particles) are commonly used in civil engineering (for example, in order to form a retaining wall). Static tensile tests of single wire and double-twisted wire were performed. The stiffness and ultimate tensile strength were examined. Special attention was paid to the double-twist behaviour. The unloading tests were also performed and the range of elastic deformation of both single wire and double-twisted wire were determined. The obtained laboratory results (stress–strain relationships for single wire and double-twisted wire) were included in a numerical model of the repeatable cell of mesh (truss model). The simulation in both directions, parallel and perpendicular to the double twist, was performed. On the basis of the obtained load-strain relationship, an anisotropic membrane model for mesh was proposed and calibrated. The obtained value of tensile strength of the mesh (266 kN/m) is much higher than for other meshes known form literature (30–60 kN/m).
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Authors and Affiliations

Michał Grodecki
1
ORCID: ORCID
Krzysztof Nowak
1
ORCID: ORCID

  1. Cracow University of Technology, Civil Engineering Department, 24 Warszawska Str., 31-155 Cracow, Poland
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Abstract

The composite materials as FRP (Fiber Reinforced Polymers), which are characterized by benefits resulting from the combination of high strength reinforcement (as carbon, glass, steel or aramid fibers) with synthetic matrix are increasingly used to reinforce existing structures. Reinforcing System as FRCM (Fibre Reinforced Cementitious Matrix), which includes, among others, Ruredil X Mesh Gold System, is much less commonly used. However, the uniform and practical methods for calculating composite reinforced structures are not determined. Especially when considering the real conditions of structure exploitation, which requires further research in this field. In the paper the initial loading level influence on the efficiency of reinforced concrete beams strengthen using system Ruredil X Mesh Gold was investigated.

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Authors and Affiliations

Z. Blikharskyy
K. Brózda
J. Selejdak
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Abstract

This article summarizes technical aspects of preparing printable 3D anatomical models created from radiological data (CT, MRI) and discusses their usefulness in surgery of the human skull. Interdisciplinary approach to the capabilities of the 3D printers, and the materials used for manufacturing 3D objects oriented on replicating anatomical structures has created new possibilities for simulating and planning surgical procedures in clinical practice settings.
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Authors and Affiliations

Janusz Skrzat
1

  1. Department of Anatomy, Jagiellonian University Medical College, Kraków, Poland
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Abstract

The anatomy of the human temporal bone is complex and, therefore, poses unique challenges for students. Furthermore, temporal bones are frequently damaged from handling in educational settings due to their inherent fragility. This report details the production of a durable physical replica of the adult human temporal bone, manufactured using 3D printing technology. The physical replica was printed from a highly accurate virtual 3D model generated from CT scans of an isolated temporal bone. Both the virtual and physical 3D models accurately reproduced the surface anatomy of the temporal bone. Therefore, virtual and physical 3D models of the temporal bone can be used for educational purposes in order to supplant the use of damaged or otherwise fragile human temporal bones.

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Authors and Affiliations

Janusz Skrzat
Matthew J. Zdilla
Paweł Brzegowy
Mateusz Hołda
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Abstract

We apply a fluid-structure interaction method to simulate prototypical dynamics of the aortic heart-valve. Our method of choice is based on a monolithic coupling scheme for fluid-structure interactions in which the fluid equations are rewritten in the 'arbitrary Lagrangian Eulerian' (ALE) framework. To prevent the backflow of structure waves because of their hyperbolic nature, a damped structure equation is solved on an artificial layer that is used to prolongate the computational domain. The increased computational cost in the presence of the artificial layer is resolved by using local mesh adaption. In particular, heuristic mesh refinement techniques are compared to rigorous goal-oriented mesh adaption with the dual weighted residual (DWR) method. A version of this method is developed for stationary settings. For the nonstationary test cases the indicators are obtained by a heuristic error estimator, which has a good performance for the measurement of wall stresses. The results for prototypical problems demonstrate that heart-valve dynamics can be treated with our proposed concepts and that the DWR method performs best with respect to a certain target functional.

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Authors and Affiliations

Thomas Wick
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Abstract

This paper presents novel discrete differential operators for periodic functions of one- and two-variables, which relate the values of the derivatives to the values of the function itself for a set of arbitrarily chosen points over the function’s area. It is very characteristic, that the values of the derivatives at each point depend on the function values at all points in that area. Such operators allow one to easily create finite-difference equations for boundaryvalue problems. The operators are addressed especially to nonlinear differential equations.
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Authors and Affiliations

Tadeusz Jan Sobczyk
1
ORCID: ORCID

  1. Department of Electrical Engineering, Faculty of Electrical and Computer Engineering, Cracow University of Technology, 24 Warszawska str., 31-155 Kraków, Poland
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Abstract

This study proposes the LoRa-Based Mesh Sensor Network without relying on LoRaWAN connection sending the communication data in the form of Star-to-Star, it can be sends the data in the form of peer-to-peer without the gateway. In the case that a longer distance is needed, the system is connected by a means of multi-hop presenting the hardware and software model through the use of low voltage power. Then, the testing is done using point to point and the received signal is measured by a gauge and compared with the model in accordance with the theoretical principle.
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Authors and Affiliations

Jarun Khonrang
1
Mingkwan Somphruek
1
Pairoj Duangnakhorn
1
Atikhom Siri
1
Kamol Boonlom
2

  1. Chiang Rai Rajabhat University, Thailand
  2. University of Leeds, United of Kingdom
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Abstract

The works presents the application of mass/volume balances of liquid drug converted into the aerosol during atomization in medical nebulizers. The amount of liquid that can be delivered to the respiratory system during inhalation is reduced compared to the nominal dose not only because of drug losses both in the device (the residual volume, RV) and outside the nebulizer (in the mouthpiece, mask, or tubings), but also to the limitations of the patient (periodic flow with limited capacity). The paper should help to understand the complexity of aerosol therapy widely used in asthma, COPD and other pulmonary diseases.
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Authors and Affiliations

Tomasz R. Sosnowski
1
ORCID: ORCID
Kamil Janeczek
2
Karolina Grzywna
3 4
Andrzej Emeryk
2

  1. Warsaw University of Technology, Faculty of Chemical and Process Engineering, Warynskiego 1, 00-645 Warsaw, Poland
  2. Medical University of Lublin, Clinics of Lung Diseases and Pediatric Reumathology, Gebali 6, 20-093 Lublin, Poland
  3. Silesian Medical University in Katowice, Student Scientific Club at the Chair and Division of Pathomorphology and Molecular Diagnostics, Medyków 18, 40-752 Katowice, Poland
  4. Silesian Medical University in Katowice, Faculty of Medical Sciences in Zabrze, Traugutta sq. 2, 41-800 Zabrze, Poland
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Abstract

Rehabilitation treatments applied to a local road prone to terrain subsidence from mining excavation should be designed considering cost-efficient and effective reinforcement solutions. In the analysed case, a glass-fibre mesh was applied under asphalt concrete layers in 2008, in one lane while another was left without the reinforcement. The main objective of this paper was to investigate the effectiveness of reinforcement by analysing the amount of produced on the pavement and the influence on pavement deflection. It was found that the reinforcement retracted the number of cracks, however, did not affect the bearing capacity. The influence of the applied geosynthetic was manifested in the values of the radius of curvature. The overall technical state of the road requires immediate treatment and the applied reinforcement proved obsolete because in this particular case of road located in the mining active terrain the glass fiber mesh did not prolong the life of the pavement.
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Authors and Affiliations

Mateusz Kałuża
Mirosław Kotasiński
1
ORCID: ORCID
Joanna Bzówka
1
ORCID: ORCID

  1. Silesian University of Technology, Faculty of Civil Engineering, Akademicka 5, 44-100 Gliwice, Poland
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Abstract

This paper presents the results of Finite Element Method (FEM) modeling of double-twisted steel hexagonal wire mesh used to construct gabion cages. Gabion cages, filled with soil (usually rock particles) are commonly used in civil engineering (for example in order to form a retaining wall). Static tensile tests are modeled and the obtained force - displacements curves are compared with the laboratory test results (known from literature). Good accordance between numerical and laboratory test results is observed. Three different material models for single wire and double twist are tested. Special attention is paid to double-twist modelling. Simulations of the damaged mesh are also performed, strength and stiffness reduction is analyzed. Anisotropic membrane model for mesh is proposed and calibrated. Parameters for homogenized Coulomb - Mohr media for gabion (filling and mesh) are estimated. Such homogenized Coulomb - Mohr model could be used in engineering practice to model behaviour of real gabion structures.

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Authors and Affiliations

Michał Grodecki
ORCID: ORCID

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