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Experimental study on the wear evolution of different PVD coated tools under milling operations of LDX2101 duplex stainless steel

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Advances in Manufacturing 2023年第1期11卷 158-179页

作者： vitor f.c.sousa francisco J.G.Silva Ricardo Alexandre Jose S.fecheira Gustavo Pinto Andresa Baptista ISEP-School of Engineering Polytechnic of PortoRua Dr.António Bernardino de Almeida4314200–072PortoPortugal INEGI-Driving Science and Innovation Rua Dr.Roberto Frias4004200–465PortoPortugal TEandM-Technology Engineering and MaterialsS.A.Parque Industrial do TaveiroLotes 41-423045–504TaveiroPortugal

Duplex stainless steels are being used on applications that require,especially,high corrosion resistance and overall good mechanical properties,such as the naval and oil-gas exploration *** components employed in these industries are usually obtained by machining,however,these alloys have low machinability when compared to conventional stainless *** this work,a study of the wear developed when milling duplex stainless-steel,LDX 2101,is going to be presented and evaluated,employing four types of milling tools with different geometries and coatings,while studying the influence of feed rate and cutting length in the wear of these *** used have been provided with two and four flutes,as well as three different coatings,namely:TiAlN,TiAlSiN and *** cutting behavior of these tools was analyzed;data relative to the cutting forces developed during the process were obtained;and roughness measurements of the machined surfaces were *** tools were then submitted to scanning electron microscope(SEM)analysis,enabling the identification of the wear mechanisms that tools were subjected to when machining this material,furthermore,the early stages of these mechanisms were also *** this work was done with the goal of relating the machining parameters and cutting force values obtained,identifying,and discussing the wear patterns that were observed in the coating and tools after the milling tests,providing further information on the machining of these alloys.

关键词： Duplex stainless-steel Milling Tool coatings Surface roughness Wear mechanisms

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Parallel LDPc Decoding on GPUs Using a Stream-Based computing Approach

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Journal of computer Science & Technology 2009年第5期24卷 913-924页

作者： Gabriel falcao Student Member Shinichi Yamagiwa vitor Silva Leonel sousa Senior Member Department of Electrical and computer Engineering University of Coimbra Instituto de Telecomunicacoes PoloⅡUniversidade de Coimbra 3030-290 Coimbra Portugal INESc-ID Technical University of Lisbon Rua Alves Redol n.9 1000-029 Lisboa Portugal Department of Electrical and computer Engineering IST Technical University of Lisbon Rua Alves Redol n.9 1000-029 Lisboa Portugal

Low-Density Parity-check （LDPc） codes are powerful error correcting codes adopted by recent communication standards. LDPc decoders are based on belief propagation algorithms, which make use of a Tanner graph and very intensive message-passing computation, and usually require hardware-based dedicated solutions. With the exponential increase of the computational power of commodity graphics processing units （GPUs）, new opportunities have arisen to develop general purpose processing on GPUs. This paper proposes the use of GPUs for implementing flexible and programmable LDPc decoders. A new stream-based approach is proposed, based on compact data structures to represent the Tanner graph. It is shown that such a challenging application for stream-based computing, because of irregular memory access patterns, memory bandwidth and recursive flow control constraints, can be efficiently implemented on GPUs. The proposal was experimentally evaluated by programming LDPc decoders on GPUs using the caravela platform, a generic interface tool for managing the kernels＇ execution regardless of the GPU manufacturer and operating system. Moreover, to relatively assess the obtained results, we have also implemented LDPc decoders on general purpose processors with Streaming Single Instruction Multiple Data （SIMD） Extensions. Experimental results show that the solution proposed here efficiently decodes several codewords simultaneously, reducing the processing time by one order of magnitude.

关键词： data-parallel computing graphics processing unit (GPU) caravela low-density parity-check (LDPc) code error correcting code

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Nutritional supplements use in high-performance athletes is related with lower nutritional inadequacy from food

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Journal of Sport and Health Science 2016年第3期5卷 368-374页

作者： Mónica sousa Maria J.fernandes Pedro carvalho José Soares Pedro Moreira vitor Hugo Teixeira centre of Research Education Innovation and Intervention in Sport Faculty of Sport University of Porto faculty of Nutrition and food Sciences University of Porto Research centre on Physical Activity Health and Leisure Faculty of Sport University of Porto

Background: The use of nutritional supplements(NS) among athletes is widespread. However, little is known about the relationship between nutritional adequacy and NS usage. The aims of this study were to evaluate the NS usage and to compare the nutritional intake from food and prevalence of micronutrient inadequacy(PMI) between NS users and ***: Portuguese athletes from 13 sports completed an NS usage questionnaire and a semi-quantitative food-frequency questionnaire assessing information over the previous 12 months. The estimated average requirement cut-point method was used to calculate PMI. General linear models were used to compare nutritional intake and NS usage. chi-squared tests and logistic regression were performed to study, respectively,relationships and associations between PMI and NS ***: from the 244 athletes(66% males, 13–37 years), 64% reported NS usage. After adjustment, NS users showed a higher intake from food(p for at least 1 gender, for energy, and for 7 of the 17 studied nutrients. The highest PMI were seen for vitamins D and E, calcium, folate,and magnesium. After adjustment, NS users, irrespective of gender, reported lower PMI for calcium(OR = 0.28, 95%cI: 0.12–0.65), and female users for magnesium(OR = 0.06, 95%cI: 0.00–0.98).conclusion: Athletes using NS reported a higher nutritional intake from food, and a lower PMI for several nutrients. Perhaps, those who were taking NS were probably the ones who would least benefit from it.

关键词： carbohydrates Minerals Proteins Sport Vitamins

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On the Ranks of Semigroups of Transformations on a finite Set with Restricted Range

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Algebra colloquium 2014年第3期21卷 497-510页

作者： vitor H. fernandes Departamento de Matematica Faculdade de Ciencias e Tebcnologia Universidade Nova de Lisboa Monte da Caparica 2829-516 Caparica Portugal centro de Algebra da Universidade de Lisboa Av. Prof. Gama Pinto 2 1649-003 Lisboa Portugal Department of Mathematics Faculty of Science Chiang Mai University Chiang Mai 50200 Thailand Material Science Research center Faculty of Science Chiang Mai University Chiang Mai 50200 Thailand

Let ΡΥ（X） be the semigroup of all partial transformations on X, Υ（X） and Ι（X） be the subsemigroups of ΡΥ（X） of all full transformations on X and of all injective partial transformations on X, respectively. Given a non-empty subset Y of X, let ΡΥ（X, Y） = {α∈ ΡΥ（X）： Xα Y}, Υ（X, Y） = ΡΥ（X, Y） ∩Υ（X） and Ι（X, Y） = ΡΥ（X, Y） ∩ Ι（X）. In 2008, Sanwong and Sommanee described the largest regular subsemigroup and determined Green＇s relations of Υ（X,Y）. In this paper, we present analogous results for bothΡ Υ（X, Y） and Ι（X, Y）. for a finite set X with ｜x｜≥ 3, the ranks of ΡΥ（X） = ΡΥ（X, X）, Υ（X） = Υ（X, X） and.Ι（X） = Ι（X, X） are well known to be 4, 3 and 3, respectively. In this paper, we also compute the ranks of ΡΥ（X,Y）, Υ（X, Y） and Ι（X, Y） for any proper non-empty subset Y of X.

关键词： transformations restricted range regular elements Green's relations rank

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Oxidative stress in N88S seipinopathy:novel insights into the mechanisms of neurodegeneration and therapeutic avenues

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Neural Regeneration Research 2023年第8期18卷 1719-1720页

作者： Vítor costa vitor Teixeira i3S-Instituto de Investigação e Inovação em Saúde Universidade do PortoPortoPortugal Yeast Signalling Networks IBMC-Instituto de Biologia Molecular e CelularUniversidade do PortoPortoPortugal IcBAS Instituto de Ciências Biomédicas Abel SalazarUniversidade do PortoPortoPortugal

Lipid droplets (LDs) are ubiquitous cellular orga nelles that perform functions mostly dedicated to energy homeostasis and lipid *** neutral lipid depots (triacylglycerol,sterol esters),they can be rapidly mobilized through lipase-mediated hydrolysis (lipolysis) or via lipophagy,a specific form of autophagy devoted to consumption of LDs inside the lysosome.

关键词： hydrolysis insight devoted

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Possible high cOVID-19 airborne infection risk in deep and poorly ventilated 2D street canyons

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Building Simulation 2023年第9期16卷 1617-1628页

作者： vitor Lavor Omduth coceal Sue Grimmond Jian Hang Zhiwen Luo School of the Built Environment University of ReadingReadingUK Department of Meteorology University of ReadingReadingUK School of Atmospheric Sciences Guangdong Province Key Laboratory for Climate Change and Natural Disaster StudiesSun Yat-sen UniversityGuangzhouChina Welsh School of Architecture Cardiff UniversityCardiffUK

Despite the widespread assumption that outdoor environments provide sufficient ventilation and dilution capacity to mitigate the risk of cOVID-19 infection,there is little understanding of airborne infection risk in outdoor urban areas with poor *** address this gap,we propose a modified Wells-Riley model based on the purging flow rate(QPfR),by using computational fluid dynamics(cfD)*** model quantifies the outdoor risk in 2D street canyons with different approaching wind speeds,urban heating patterns and aspect ratios(building height to street width).We show that urban morphology plays a critical role in controlling airborne infectious disease transmission in outdoor environments,especially under calm winds;with deep street canyons(aspect ratio>3)having a similar infection risk as typical indoor *** ground and leeward wall heating could reduce the risk,windward heating(e.g.,windward wall~10 K warmer than the ambient air)can increase the infection risk by up to 75%.Our research highlights the importance of considering outdoor infection risk and the critical role of urban morphology in mitigating airborne infection *** identifying and addressing these risks,we can inform measures that may enhance public health and safety,particularly in densely populated urban environments.

关键词： airborne infection risk street canyon urban ventilation wall heating cfD modelling

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A Building classification System for Multi-hazard Risk Assessment

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International Journal of Disaster Risk Science 2022年第2期13卷 161-177页

作者： vitor Silva Svetlana Brzev charles Scawthorn catalina Yepes Jamal Dabbeek Helen crowley Risk Section Global Earthquake Model27100 PaviaItaly Department of civil Engineering University of British ColumbiaVancouverBC V6T 1Z4Canada SPA Risk LLc DenverCO 80207USA Department of civil Engineering An-Najah National UniversityNablusState of Palestine Seismic Risk Section 27100 EucentrePaviaItaly

A uniform and comprehensive classification system, often referred to as taxonomy, is fundamental for the characterization of building portfolios for natural hazard risk assessment. A building taxonomy characterizes assets according to attributes that can influence the likelihood of damage due to the effects of natural *** the scope of the Global Earthquake Model(GEM)initiative, a building taxonomy(GEM Building Taxonomy V2.0) was developed with the goal of classifying buildings according to their seismic vulnerability. This taxonomy contained 13 building attributes, including the main material of construction, lateral load-resisting system, date of construction and number of stories. Since its release in2012, the taxonomy has been used by hundreds of experts working on exposure and risk modeling efforts. These applications allowed the identification of several limitations, which led to the improvement and expansion of this taxonomy into a new classification system compatible with multi-hazard risk assessment. This expanded taxonomy(named GED4ALL) includes more attributes and several details relevant for buildings exposed to natural hazards beyond earthquakes. GED4ALL has been applied in several international initiatives, enabling the identification of the most common building classes in the world, and facilitating compatibility between exposure models and databases of vulnerability and damage databases.

关键词： Disaster risk Exposure Multihazard Taxonomy

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Statistical Properties of a System consisting of a Superconducting Qubit coupled to an Optical field Inside a Transmission Line

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communications in Theoretical Physics 2018年第6期69卷 727-734页

作者： clodoaldo Valverde Gabriela Rodrigues Vaz vitor Teles de Oliveira Basilio Baseia campus de ciSncias Exatas e Tecnologicas Universidade Estadual de GoiaisBR 153km 9875.132-903 AnapolisGOBrazil Universidade Paulista(UNIP)-74.845-090 GoianiaGoiasBrazil Instituto de ffsica Universidade Federal de Goias-74.001-970GoianiaGoiasBrazil Departamento de fisica Universidade Federal da Paraiba-58.051-970Joao PessoaParaibaBrazil

The present work investigates the entropy and the excitation inversion of a coupled system that consists of a qubit represented by a cooper pair box （cPB） interacting with a transmission line working as a circuit quantum eleetrodynamics （cQED）. The proposed scheme uses the Buck-Sukumar model with a time dependent frequency in the presence of losses to study the evolution of the entropy and the excitation inversion of the system. We have shown that the cQED is much more sensitive to the presence of losses than the cPB. The results also show that it is possible to monitor properties of the subsystems through appropriate choices of the time-dependent parameters.

关键词： excitation inversion transmission line entropy Buck-Sukumar model

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Seismic Risk Model for the Beijing-Tianjin-Hebei Region,china:considering Epistemic Uncertainty from the Seismic Hazard Models

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International Journal of Disaster Risk Science 2024年第3期15卷 434-452页

作者： Jian Ma Katsuichiro Goda Kai Liu Silva vitor Anirudh Rao Ming Wang Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationKey Laboratory of Earthquake Disaster MitigationMinistry of Emergency ManagementHarbin150080China School of National Safety and Emergency Management Beijing Normal UniversityBeijing100875China Department of Earth Sciences Western UniversityLondonN6A 5B7Canada Global Earthquake Model foundation 27100PaviaItaly Shenzhen Key Laboratory of Urban Disasters Digital Twin Shenzhen518023China

This study presents a probabilistic seismic risk model for the Beijing-Tianjin-Hebei region in *** model comprises a township-level residential building exposure model,a vulnerability model derived from the chinese building taxonomy,and a regional probabilistic seismic hazard *** three components are integrated by a stochastic event-based method of the OpenQuake engine to assess the regional seismic risk in terms of average annual loss and exceedance probability curve at the city,province,and regional *** novelty and uniqueness of this study are that a probabilistic seismic risk model for the Beijing-Tianjin-Hebei region in china is developed by considering the impact of site conditions and epistemic uncertainty from the seismic hazard model.

关键词： Beijing-Tianjin-Hebei region Epistemic uncertainty Seismic risk assessment Seismic risk model

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Evaluation of Novel 3D Architectures Based on Knitting Technologies for Engineering Biological Tissues

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Journal of Donghua University(English Edition) 2013年第5期30卷 421-426页

作者： RIBEIRO Viviana Pinto RIBEIRO Ana Soares SILVA carla Joana DURES Nelson feio BONIfcIO Graa cORRELO vitor Manuel MARQUES Alexandra Pinto sousa Rui Amandi OLIVEIRA Ana Leite REIS Rui Luís 3B's Research G roup-Biomaterials Biodegradables and BiomimeticsUniversity of MinhoHeadquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine IcVS /3B's-PT G overnment Associated Laboratory University of Minho ceNTI Centre for Nanotechnology and Smart MaterialsV. N. cITEVE Technological Centre for Textile and Clothing IndustryV. N. cBQf-School of Biotechnology Portuguese Catholic University

Textile-based technologies are considered as potential routes for the production of 3D porous architectures for tissue engineering( TE) applications. We describe the use of two polymers,namely polybutylene succinate( PBS) and silk fibroin(Sf) to produce fiber-based finely tuned porous architectures by weft and warp knittings. The obtained knitted constructs are described in terms of their morphology, mechanical properties,swelling ability,degradation behaviour,and cytotoxicity. Each type of polymer fibers allows for the processing of a very reproducible intra-architectural scaffold geometry,with distinct characteristics in terms of the surface physicochemistry,mechanical performance,and degradation capability,which has an impact on the resulting cell behaviour at the surface of the respective biotextiles. Preliminary cytotoxicity screening shows that both materials can support cell adhesion and proliferation. furthermore, different surface modifications were performed( acid /alkaline treatment, UV radiation,and plasma) for modulating cell behavior. An increase of cell-material interactions were observed,indicating the important role of materials surface in the first hours of culturing. Human adipose-derived stem cells( hAScs) became an emerging possibility for regenerative medicine and tissue replacement therapies. The potential of the recently developed silk-based biotextile structures to promote hAScs adhesion,proliferation,and differentiation is also evaluated. The obtained results validate the developed constructs as viable matrices for TE applications. Given the processing efficacy and versatility of the knitting technology, and the interesting structural and surface properties of the proposed polymer fibers,it is foreseen that our developed systems can be attractive for the functional engineering of tissues such as bone,skin,ligaments or cartilage and also for develop more complex systems for further industrialization of TE products.

关键词： textile-based technologies silk polybutylene succinate(PBS) surface modifications human adipose-derived stem cells(hAScs) tissue engineering(TE)

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