检索结果-内蒙古大学图书馆

Assessment of HVAF thermally sprayed coatings: Unraveling microstructural, electrochemical, and tribological performance using glass former Fe-Cr-Mo-Nb-B feedstock powder

Journal of Alloys and Metallurgical Systems

引用

Journal of Alloys and Metallurgical systems 2024年 6卷

作者： Mota, I.G.C. Koga, G.Y. Rodrigues, L.C.M. Nascimento, A.R.C. Ettouil, F.B. Ferreira, T. Coimbrão, D.D. Kiminami, C.S. Bolfarini, C. Moreau, C. Botta, W.J. Federal University of São Carlos Graduate Program in Materials Science and Engineering Rod. Washington Luis km 235 SP São CarlosCEP 13565-905 Brazil Federal University of São Carlos Department of Materials Science and Engineering Rod. Washington Luis km 235 SP São CarlosCEP 13565-905 Brazil Federal University of Sao Carlos Rodovia Washington Luiz km 235 SP-310 São Paulo São Carlos13565-905 Brazil Thermal Spray and Multiphase Flow Laboratory Concordia University MontrealQCH3G 1M8 Canada Department of Mechanical Industrial and Aerospace Engineering Concordia University 1455 de Maisonneuve Blvd. W MontrealQCH3G 1M8 Canada

In this paper the microstructural features of the glass former Fe68Cr8Mo4Nb4B16 coatings are unveiled and related to their electrochemical and tribological responses. The coating was mostly glassy with some embedded borides (M3B2, M2B-tetragonal;M being the metallic elements of the alloy) and ferrite. The tribological behavior of the HVAF coated sample, characterized by a thickness of about 200 µm, ∼6% porosity and a Vickers hardness of 357 HV0.5, was assessed in a sphere-on-plate configuration, revealing a specific wear rate of approximately 5 ×10−4 mm3∙N−1m−1. The wear mechanism was dominated by delamination caused by fragile intersplats. The corrosion resistance of HVAF coatings was evaluated in 0.6 M NaCl solution and compared with the results obtained for the crystalline Fe68Cr8Mo4Nb4B16 ingot, produced by melting in an induction furnace, and for the AISI 1020 steel substrate. The HVAF coating showed satisfactory corrosion resistance compared to the carbon steel substrate and the crystalline ingot, with the highest corrosion potential, Ecorr, values (−533 mVSCE) and the lowest corrosion current density, icorr, (10−6 A∙cm−2) followed by a clear passivation window upon anodic polarization in 0.6 M NaCl solution. Evaluations of HVAF coating showed a higher glassy content compared to the gas-atomized feedstock powders. This suggests that during spraying, certain particles were molten and experienced cooling rates adequate to inhibit crystallization, resulting in the freezing of the supercooled liquid. This phenomenon contributes to the good corrosion resistance observed in the present work and offers an opportunity to enhance the electrochemical behavior of HVAF coatings. © 2024 The Authors

关键词： Wear of materials

来源：评论

学校读者我要写书评

暂无评论

Capacity Planning of Access Point Deployment for Indoor Positioning System

Capacity Planning of Access Point Deployment for Indoor Posi...

引用

Conference on Power, Energy and Innovations (ICPEI)

作者： Aphirak Thitinaruemit Suchada Sitjongsatapom Sethakarn Prongnuch The Electrical Engineering Graduate Program Faculty of Engineering and Technology Mahanakorn University of Technology Bangkok Thailand Mahanakorn Institute of Innovation (MII) Faculty of Engineering and Technology Mahanakorn University of Technology Bangkok Bangkok Thailand Faculty of Industrial Technology Suan Sunandha Rajabhat University Bangkok Thailand

ISBN: (纸本)9781665402170

This paper present the network design and capacity planning of access point (AP) deployment for indoor positioning system. The estimation of WiFi distance is described briefly how to measure the signal strength of AP. Co-channel interference is a key for network design of access point installation for network capacity. The objective function for network capacity planning of AP deployment is to optimize the number of access point and location for indoor positioning system concerning with the minimized co-channel interference. Simulations are tested to install AP for lecture hall in university. Capacity planning design of wireless AP deployment is proposed for indoor position systems in terms of the received signal strength indications (RSSI). We assume the situation is supported for the crowded conference. The requirement of the results of wireless AP positioning in crowded conference rooms are placing the wireless AP in forms of overlap the signal in order to get the strong signal. Experimental results have been tested their received signal of WiFi APs with the 2.4GHz frequency using the receiver installed in laptops to check the signal. The empirical results shown that the strength of RSSI will be received a signal of -44 dBm at a distance of approximately 20 meters.

关键词： Meters Technological innovation Portable computers Receivers Wireless access points Linear programming Received signal strength indicator

来源：评论

学校读者我要写书评

暂无评论

Improved lattice Boltzmann model for immiscible multicomponent systems with high viscosity gradients at the interface

引用

Physical Review E 2024年第1期110卷 015303-015303页

作者： Ricardo L. M. Bazarin Christian Naaktgeboren Silvio L. M. Junqueira Paulo Cesar Philippi Luiz Adolfo Hegele, Jr. Porous Media Research Group (PORO) Scientific Computational Laboratory <a href="https://***/041akq887">Federal University of Santa Catarina</a> 89219-600 Joinville SC Brazil. Hermann von Helmholtz Energy Research Group <a href="https://***/002v2kq79">Federal University of Technology</a> Av. Guarapuava 800. Cidade dos Lagos 85053-525 Guarapuava PR Brazil. Research Center for Rheology and Non-Newtonian Fluids <a href="https://***/002v2kq79">Federal University of Technology</a> 81280-340 R. Deputado Heitor Alencar Furtado 5000 - Bloco N - Ecoville Curitiba PR Brazil. Mechanical Engineering Graduate Program <a href="https://***/02x1vjk79">Pontifical Catholic University of Parana</a> 80215-901 Curitiba PR Brazil. Department of Petroleum Engineering <a href="https://***/03ztsbk67">Santa Catarina State University</a> 88336-275 Balneário Camboriú SC Brazil.

We propose alternative discretization schemes for improving the lattice Boltzmann pseudopotential model for incompressible multicomponent systems, with the purpose of modeling the flow of immiscible fluids with a large viscosity ratio. Compared to the original model of Shan-Chen [Phys. Rev. E 47, 1815 (1993)], the present discretization schemes consider: (i) an explicit force term, (ii) a second-order discretization of the stream term, (iii) a moments-based model for the kinetic nonequilibrium distributions, and (iv) a high-order discretization of the spatial derivative terms. To verify the accuracy of the proposed model, the effects of varying the viscosity ratio as well as both fluid's viscosities on spurious currents and capillary number are investigated for the problems dealing with a static bubble, two-component Poiseuille flow, and immiscible fluid-fluid displacement. The resulting algorithm maintains the simplicity of the pseudopotential model while allowing an easy implementation for multicomponent systems. The results of the model herein proposed show improved control of the interface region and interfacial tension, relatively smaller magnitudes of spurious current values with increasing viscosity ratio, and also a significantly wider stability range with respect to the previously best results in the literature.

关键词： Displacement of immiscible fluids Surface tension effects Multiphase flows Lattice-Boltzmann methods

来源：评论

学校读者我要写书评

暂无评论

A damage sensitive feature: Beam case 1

A damage sensitive feature: Beam case

引用

1st International Symposium on Advances and Innovations in mechanical engineering, ISAIME 2019

作者： Gunawan, Fergyanto E. Sekishita, Nobumasa Industrial Engineering Department BINUS Graduate Program - Master of Industrial Engineering Bina Nusantara University Jakarta11480 Indonesia Department of Mechanical Engineering Toyohashi University of Technology Aichi Toyohashi441-8580 Japan

With the adoption of damage tolerance design principle, the health monitoring system has become an integral part of the engineering structure in operation. For the system to work, damage indicator that describes the structural integrity level should be established and monitored. Damage indicator is usually derived from structural responses. Many quantities have been proposed for damage indicator. Some popular damage indicators are natural frequency, mode shape, curvature, strain energy, and t-, F-, and z-statistics. In this paper, we propose a new damage indicator derived from the theory of the strength of materials. We evaluate the proposal for a case involving damage on a simply-supported beam. The required data are established numerically by the finite element method for structure in healthy and damaged conditions. The results suggest that the current proposal is more sensitive to damage than the natural frequency. © Published under licence by IOP Publishing Ltd.

关键词： Natural frequencies

来源：评论

学校读者我要写书评

暂无评论

GIS-based methodology on techno-economic potential assessment of sugarcane residues in Medellin, Cebu, Philippines 40

GIS-based methodology on techno-economic potential assessmen...

引用

40th Asian Conference on Remote Sensing: Progress of Remote Sensing Technology for Smart Future, ACRS 2019

作者： Galang, Wenyville Tabañag, Ian Dominic Loretero, Michael Engineering Graduate Program School of Engineering University of San Carlos Cebu City6000 Philippines College of Engineering and Computer Studies Holy Name University Tagbilaran City6300 Philippines Department of Chemical Engineering University of San Carlos Cebu City6000 Philippines Department of Mechanical and Manufacturing Engineering University of San Carlos Cebu City6000 Philippines

The act of burning traditional biomass results in indoor air pollution, which has negative effects on health such as respiratory, pulmonary, and cardiovascular diseases. The practice also contributes to ambient air pollution and climate change through the emission of carbon dioxide (CO2) and non-CO2 pollutants formed by the incomplete combustion of biomass. To help reduce air pollution coupled with its effect on climate change specifically the agricultural residues left on fields and burned, a Geographic Information System (GIS) supported assessment was developed to determine the techno-economic potentials of utilizing agricultural residues in Medellin, Cebu. The methodology was based on GIS analysis of agricultural, economic and climatic data employed in GIS spatial analysis platform. Data about land use, transportation facilities, urban cartography, regional territorial planning, terrain digital model, and climatic types have been stored in the GIS to define potential areas for gathering the residues coming from sugarcanes and to assess available for energy cultivation. The sugarcane is an abundant agricultural crop in the locality and its residue is the major feedstock available for bioenergy. The results reveal a meaningful technical and economic potential concentration in the locality feasible for biomass power plant for electricity generation. The assessment has shown a strong competitiveness of sugarcane residues for bioenergy when the collection system is implemented in an efficient way. An outcome of the study was to show the opportunities originating from issue of addressing energy security by utilizing indigenous energy resources. © 2020 40th Asian Conference on Remote Sensing, ACRS 2019: "Progress of Remote Sensing Technology for Smart Future". All rights reserved.

关键词： Geographic information systems

来源：评论

学校读者我要写书评

暂无评论

Numerical simulation of coalescence and break-up of drops in shear flow based on the meshless localized radial basis function method 10

Numerical simulation of coalescence and break-up of drops in...

引用

10th International Conference on Physics and Its Applications, ICOPIA 2020

作者： Pranowo Wijayanta, Agung Tri Itaya, Yoshinori Informatics Department Faculty of Industrial Technology Universitas Atma Jaya Yogyakarta Jl. Babarsari 43 Yogyakarta55281 Indonesia Research Group of Sustainable Thermofluids Engineering Faculty Universitas Sebelas Maret Jl. Ir. Sutami 36A Kentingan Surakarta57126 Indonesia Mechanical Engineering Department Faculty of Engineering Universitas Sebelas Maret Jl. Ir. Sutami 36A Kentingan Surakarta57126 Indonesia Environmental and Renewable Energy Systems Division Graduate School of Engineering Gifu University 1-1 Yanagido Gifu-shi Gifu501-1193 Japan

In the present paper, the meshless localized radial basis function (RBF) is proposed for simulating of two-phase incompressible viscous flow. Due to the velocity of the shear flow is very low, the fluid can modeled by Stokes equations. For more convenience the primitive variables, i.e., pressure and velocity components of the Stokes equations are transformed into stream function formulation. The interface of the fluid system is modeled by using Cahn-Hilliard equation. The spatial terms of the governing equations are discretized numerically by using the RBF method. The temporal term is integrated by using fully implicit Euler method. The nonlinear terms of Cahn-Hilliard equation is linearized using the Picard iteration. The proposed method is applied to simulate coalescence and break-up of drops in shear flow. The numerical results show that the deformation of the interface can be modeled without any difficulties. © 2021 Institute of Physics Publishing. All rights reserved.

关键词： Shear flow

来源：评论

学校读者我要写书评

暂无评论

Direct control of machine tools using 3D-CAD 34

Direct control of machine tools using 3D-CAD

引用

34th Annual Meeting of the American Society for Precision engineering, ASPE 2019

作者： Sagesaka, Koki Morimoto, Yoshitaka Hayashi, Akio Graduate Program in Mechanical Engineering Kanazawa Institute of Technology Graduate School Ohgigaoka Nonoichi Ishikawa Japan Department of Mechanical Engineering Kanazawa Institute of Technology Ohgigaoka Nonoichi Ishikawa Japan

来源：评论

学校读者我要写书评

暂无评论

Mosaic ballistic ceramics: A review

Journal of Alloys and Compounds Communications

引用

Journal of Alloys and Compounds Communications 2024年 3卷

作者： Alexander B. Dresch Fernando Otávio Pizzatto Janio Venturini Oscar R.K. Montedo Sabrina Arcaro Carlos P. Bergmann Graduate Program in Mining Metallurgical and Materials Engineering Universidade Federal do Rio Grande do Sul Porto Alegre Brazil Graduate Program in Materials Science and Engineering Universidade do Extremo Sul Catarinense Criciúma Brazil School of Natural Sciences Department of Chemistry Technical University of Munich Garching bei München Germany Department of Industrial Engineering Universidade Federal do Rio Grande do Sul Porto Alegre Brazil

The inherent fragility of ceramic materials is an obstacle to producing ceramics that are resistant and hard. Furthermore, the use of monolithic ceramic plate armour for ballistic applications is challenging because the protections need to resist multiple impacts. One of the solutions are mosaic ceramic armour systems, which consist of ceramic tiles arranged side by side. However, there is a wide variety of ceramic tile formats, as well as different dimensions. Unlike monolithic ceramics, mosaic systems present different behaviour when subjected to a ballistic event. As a result, their energy dissipation mechanisms and the properties necessary for this purpose are distinct. The main properties of ceramic tiles are hardness, modulus of elasticity, and fracture toughness, of which the latter, according to the analysis of figures of merit, must be as low as possible, as opposed to hardness and modulus of elasticity, which are desired to be as high as possible. We can efficiently take advantage of brittle fracture mechanisms to absorb the kinetic energy of the projectile during the tile fracture. Furthermore, the gap-filling material is extremely important, as it allows the confinement of the ceramic tiles and reduces the spread of damage. Numerical analysis is a great ally for the study of ballistic ceramics, and countless variables can be considered, enabling results very close to experimental ones at a low cost. Thus, it is possible to understand the key factors for producing more efficient ballistic ceramics as well as obtaining research data that can contribute to the evolution of the ballistic protection sector. In this context, this work presents a review of ceramic mosaics for ballistic amours.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Multiscale investigation of seismic precursors before major earthquakes

引用

Mechanics Research Communications 2025年 147卷

作者： Friedrich, Leandro Ferreira Padilha, Mariana Hamdan Lacidogna, Giuseppe Iturrioz, Ignacio Graduate Program in Engineering Universidade Federal do Pampa Av. Tiaraju 810 CEP Alegrete97546-550 Brazil Department of Structural Geotechnical and Building Engineering Politecnico di Torino 24 Corso Duca degli Abruzzi Torino10129 Italy Mechanical Post-Graduate Program Universidade Federal do Rio Grande do Sul Sarmento Leite 425 CEP Porto Alegre90050-170 Brazil

In various mechanical systems, the study of damage processes can be approached from the perspective of continuous phase transition phenomena, a subject typically explored within the framework of statistical physics. This viewpoint enables a more refined interpretation of failure precursors, which are of great importance in the field. The present study investigates failure precursors through two case studies: the material failure process by using the Fiber Bundle Model and the seismicity of the 2023 Turkey Mw7.7 earthquake. To identify the criticality, two approaches are considered: (1) Natural Time (NT) analysis and (2) the Method of Critical Fluctuation-Based (MCF-B) approach. By comparing the evolution of precursors in both cases, the findings highlight their potential for predicting critical situations. © 2025 Elsevier Ltd

关键词： Large scale systems

来源：评论

学校读者我要写书评

暂无评论

Short-term forecasting of Amazon rainforest fires based on ensemble decomposition model

arXiv

引用

arXiv 2020年

作者： da Silva, Ramon Gomes Ribeiro, Matheus Henrique Dal Molin Mariani, Viviana Cocco dos Santos Coelho, Leandro Pontifical Catholic University of Parana Industrial & Systems Engineering Graduate Program Curitiba Brazil Federal Technological University of Parana Department of Mathematics Pato Branco Brazil Federal University of Parana Dept. of Electrical Eng. Curitiba Brazil Pontifical Catholic University of Parana Mechanical Engineering Graduate Program Curitiba Brazil

Accurate forecasting is important for decision-makers. Recently, the Amazon rainforest is reaching record levels of the number of fires, a situation that concerns both climate and public health problems. Obtaining the desired forecasting accuracy becomes difficult and challenging. In this paper were developed a novel heterogeneous decomposition-ensemble model by using Seasonal and Trend decomposition based on Loess in combination with algorithms for short-term load forecasting multimonth-ahead, to explore temporal patterns of Amazon rainforest fires in Brazil. The results demonstrate the proposed decomposition-ensemble models can provide more accurate forecasting evaluated by performance measures. Diebold-Mariano statistical test showed the proposed models are better than other compared models, but it is statistically equal to one of them. Copyright © 2020, The Authors. All rights reserved.

关键词： Decision making

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：