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To compute or not to compute?

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第1期6卷 85-93页

作者： Alessandra Fiore ivo vanzi Camillo Nuti Cristoforo Demartino Rita Greco Bruno Briseghella Department of Engineering and Geology University of Chieti-Pescara "G.d'Annunzio" DICAR Department of Civil Engineering and Architecture Polytechnic University of Bari College of Civil Engineering Fuzhou University Department of Architecture Roma Tre University College of Civil Engineering Nanjing Tech University DICATECH Department of Civil Engineering Environment Territory Building and Chemical Polytechnic University of Bari

In a previous paper "to retrofit or not to retrofit?"(Nuti and vanzi, 2003) a straightforward procedure able to forecast the economic return of seismic structural upgrading was presented. More recently, the authors realized that the final mathematical results can be much simplified so as to allow back-of-an-envelope computation. The title of this paper tries to highlight precisely this aspect, namely that for many a regular seismic structural upgrading cases, nearly no computation is needed(apart from one subtraction and one multiplication) to assess their economic convenience. These findings are presented and discussed in this paper, together with a state of the art on the cost-studies available in literature and technical codes. The mathematical formulation leading to the proposed approximation is suitably explained, underlining its applicability field and comparing it with the rigorous solution. Also a table and a formula are furnished that alternatively allows to calculate the maximum estimation errors, in order to obtain an upper and lower bound for the maximum amount of money which should be allocated for seismic structural upgrading.

关键词： Seismic retrofitting Structural reliability Safety Optimization Cost minimization

Volume/thrust optimal shape criteria for arches under static vertical loads

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Journal of Traffic and Transportation Engineering(English Edition) 2018年第6期5卷 503-509页

作者： Giuseppe Carlo Marano Francesco Trentadue Rita Greco ivo vanzi Bruno Briseghella DICAR Department of Civil Engineering and ArchitectureTechnical University of BariBail 70125Italy College of Civil Engineering Fuzhou UniversityFuzhou 350108China DICATECH Department of Civil EngineeringEnvironmentTerritoryBuilding and ChemicalTechnical University of BariBari 70125Italy Department of Engineering and Geology University of Chieti-Pescara "G.d'Annunzio"Pescara65127Italy

Arches are widely used when large spans are necessary, e.g. to overpass large rivers, and further possess unquestioned aesthetics advantages. Their structural efficiency depends primarily on optimal material exploitation, i.e. minimization of internal stress eccentricity,and on minimization of structural material volume. An efficient structure, under these terms, further requires simpler and lighter scaffolding, contributing in minimizing construction *** arches have millenary use and many researches dealing with this typology are available in literature, there is still scope for design optimization. The proposed study is framed within this context. Investigation is limited to statically determinate plane arches under vertical load. The problem of finding the profile of an equal strength catenary subjected to its self-weight is spread out to the case of an inverted catenary of equal strength under its self-weight and an external constant load. In the first optimization step, constant normal stress is imposed at all sections, to maximize material exploitation, and the resulting arch centerline shape is computed in closed form. In the second step, the ensemble of foundations and arch is considered and optimized, taking the linear combination of arch weight and thrust as objective function. The linear combination is dependent on a single variable, and minima of the objective function(i.e. optimal geometric shape parameters) are computed and charted to be simply used in the design process.

关键词： Plane arch Vertical loads Optimal shape Volume/thrust objective functions Analytical solution

Asynchronous earthquake strong motion and RC bridges response

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Journal of Traffic and Transportation Engineering(English Edition) 2018年第6期5卷 454-466页

作者： Davide Lavorato Gabriele Fiorentino Alessandro Vittorio Bergami Bruno Briseghella Camillo Nuti Silvia Santini ivo vanzi Department of Architecture Roma Tre University College of Civil Engineering Fuzhou University Department of Engineering and Geology University of Chieti-Pescara "G.d'Annunzio"

The dynamic response of long structures(e.g., bridges) is sensitive to the spatial variability of strong ground motion(asynchronous motion). Ground motion differences increase from point to point with increasing foundation distance. This latter is due to two physical phenomena: soil-wave interaction, that causes the loss of coherence and local amplification; wave traveling with finite velocity, that causes signals time lag. This ground motion variability produces a different structural demand compared to the synchronous one,which is the only one considered by designers in the majority of cases. A few codes consider this type of actions, therefore further research efforts are necessary. In this study,asynchronous ground motions are generated by means of a new generation procedure implemented in the software GAS 2.0 using as input the simultaneous strong motion records from the April 6 th, 2009, L’Aquila(Italy) at the seismic stations AQA and AQV, located in the Aterno River valley. These records are used to calibrate the generation model and to produce sets of asynchronous earthquake sampling. The asynchronous earthquake sets are applied on a typical highway reinforced concrete bridge to study its dynamic response considering two different configurations: non-isolated with traditional supports and isolated bridge with lead rubber bearings. The bridge is placed in two positions along the wave propagation direction: a position near one recording station and a position between the two stations to consider local soil effects. The response parameters investigated are the maximum relative displacements of soil and deck. The results show that there is animportant variation of relative displacement along the direction of wave propagation due to asynchronous motion with effects that designer should consider for the structural details design of isolated and non-isolated bridges.

关键词： Asynchronous motion Bridges Seismic response Earthquake spatial variability

Analysis of a passive ankle exoskeleton for reduction of metabolic costs during walking

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Defence Technology（防务技术） 2024年第7期37卷 62-68页

作者： Luís Quinto Pedro Pinheiro Sergio B.Goncalves ivo Roupa Paula Simoes Miguel Tavares da Silva CINAMIL Academia MilitarInstituto Universitario MilitarLisbonPortugal IDMEC Instituto Superior TecnicoUniversidade de LisboaLisbonPortugal

Modern conflicts demand substantial physical and psychological exertion,often resulting in fatigue and diminished combat or operational *** exoskeletons have been developed recently to address these challenges,presenting various limitations that affect their operational or everyday *** article evaluates the performance of a dual-purpose passive ankle exoskeleton developed for the reduction of metabolic costs during walking,seeking to identify a force element that could be applied to the target *** on the 6-min walk test,twenty-nine subjects participated in the study using three different force *** results indicate that it is possible to reduce metabolic expenditure while using the developed ***,the comfort and range of motion results verify the exoskeleton's suitability for use in uneven terrain and during extended ***,the choice of the force element should be tailored to each user,and the control system should be adjustable to optimise the exoskeleton's performance.

关键词： Ankle passive exoskeleton Metabolic cost reduction Dual-use exoskeleton Gait Biomechanics

Anomalies in the short-range local environment and atomic diffusion in single crystalline equiatomic CrMnFeCoNi highentropy alloy

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Nano Research 2024年第6期17卷 5336-5348页

作者： Alevtina Smekhova Daniel Gaertner Alexei Kuzmin Ana Guilherme Buzanich Goetz Schuck ivo Zizak Gerhard Wilde Kirill V.Yusenko Sergiy Divinski Helmholtz-Zentrum Berlin für Materialien und Energie(HZB) D-12489 BerlinGermany Institute of Materials Physics University of MünsterD-48149 MünsterGermany Institute of Solid State Physics University of LatviaLV-1063 RigaLatvia Bundesanstalt für Materialforschung und–prüfung(BAM) D-12489 BerlinGermany

Multi-edge extended X-ray absorption fine structure(EXAFS)spectroscopy combined with reverse Monte Carlo(RMC)simulations was used to probe the details of element-specific local coordinations and component-dependent structure relaxations in single crystalline equiatomic CrMnFeCoNi high-entropy alloy as a function of the annealing *** representative states,namely a high-temperature state,created by annealing at 1373 K,and a low-temperature state,produced by long-term annealing at 993 K,were compared in *** features identified in atomic configurations of particular principal components indicate variations in the local environment distortions connected to different degrees of compositional disorder at the chosen representative *** detected changes provide new atomistic insights and correlate with the existence of kinks previously observed in the Arrhenius dependencies of component diffusion rates in the CrMnFeCoNi high-entropy alloy.

关键词： high-entropy alloys diffusion short-range order extended X-ray absorption fine structure(EXAFS) reverse Monte Carlo

Influence of processing history on microstructure， mechanical properties， and electrical conductivity of Cu-0.7Mg alloy

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Transactions of Nonferrous Metals Society of China 2024年

作者： Alireza KALHOR Kinga RODAK Marek TKOCZ Bartosz CHMIELA ivo SCHINDLER ?ukasz POLOCZEK Krzysztof RADWA?SKI Hamed MIRZADEH Marian KAMPIK Faculty of Materials Engineering Silesian University of Technology V?B – Technical University of Ostrava Faculty of Materials Science and Technology Materials Research Group ?ukasiewicz Upper Silesian Institute of Technology School of Metallurgy and Materials Engineering College of Engineering University of Tehran Faculty of Electrical Engineering Silesian University of Technology

The effects of forward extrusion as well as extrusion combined with reversible torsion (KoBo extrusion)， followed by additional deformation via the MaxStrain module of the Gleeble thermomechanical simulator， on the microstructure， mechanical properties， and electrical conductivity of a Cu-0.7Mg (wt.%) alloy， were investigated in this work. The simulation results highlighted the critical influence of processing history in determining the equivalent strain distribution. The sample subjected to forward extrusion at 400 ℃and subsequent MaxStrain processing (FM sample)， possessed 76% lower grain size compared to the sample processed solely with MaxStrain (AM sample). Likewise， the KoBo-extruded and MaxStrain-processed sample (KM sample) exhibited 66% smaller grain size compared to the AM sample. Tensile test results revealed that the AM， FM， and KM samples， respectively， possessed 251%， 288%， and 360% higher yield strength， and 95%， 121%， and 169% higher tensile strength compared to the initial annealed alloy， as a result of grain refinement as well as deformation strengthening. Finally， the electrical conductivity measurements revealed that AM， FM， and KM samples， respectively， possessed electrical conductivity values of 37.9， 35.6， and 32.0 (MS/m)， which， considering their mechanical properties， makes them eligible to be categorized as high-strength and high-conductivity copper alloys.

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不同时代的赞美波瓦-迪瓦尔津Edifício A'mar建筑改造

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室内设计与装修 2024年第8期 130-135页

作者： [葡萄牙]REM’A ivo Tavares Studio(摄影) 夕阳(编译) REM'A

历史建筑Edifício A'mar位于葡萄牙波瓦-迪瓦尔津,它不仅受到市政分类保护的限制,还在当地居民心目中占有特殊地位,是城市集体记忆的重要组成部分。设计师的研究揭示了一个引人入胜的背景故事——前任业主是一位阅历丰富的旅行家,他将... 详细信息

历史建筑Edifício A'mar位于葡萄牙波瓦-迪瓦尔津,它不仅受到市政分类保护的限制,还在当地居民心目中占有特殊地位,是城市集体记忆的重要组成部分。设计师的研究揭示了一个引人入胜的背景故事——前任业主是一位阅历丰富的旅行家,他将自己的环球经历融入了这座建筑的设计理念中,最终创造出一座独特的折中主义和新文艺复兴风格的建筑杰作。设计师将这种风格称为“反应式”建筑。这项建筑工程的目标是在保护与创新之间创造一种微妙的平衡,不是对原有结构的批评,而是致敬建筑的2个不同建造时期。

关键词：当地居民分类保护建筑改造阅历丰富原有结构迪瓦尔背景故事建筑工程

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海风轻轻吹阿威罗盐色之家

室内设计与装修 2024年第8期 44-49页

作者： [葡萄牙]Rómulo De Almeida Neto ivo Tavares Studio(摄影) 西竹(编译) 不详

盐色之家(Salt Color House)位于阿威罗新海岸绿地(Costa Nova do Prado)一个被称为Mira channel的海峡沿岸。由于海水和周围植被的盐度,这个地方的颜色和散发的气味让建筑师回想起过去的时光,唤醒了童年在类似海洋氛围中的居住记忆。... 详细信息

盐色之家(Salt Color House)位于阿威罗新海岸绿地(Costa Nova do Prado)一个被称为Mira channel的海峡沿岸。由于海水和周围植被的盐度,这个地方的颜色和散发的气味让建筑师回想起过去的时光,唤醒了童年在类似海洋氛围中的居住记忆。在构思这个项目的时候,建筑师面临着巨大的挑战。一方面要抱有建筑理性的创造性,同时也要切换使用者的身份去权衡整体的使用需求。

关键词： House 海风轻轻吹建筑师

Improving the approach to non-cardiac syncope in the emergency department observation unit

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World Journal of Emergency Medicine 2023年第2期14卷 128-132页

作者： Filippo Numeroso ivo Casagranda Emergency Department University Hospital of ParmaParma 43126Italy Academy of Emergency Medicine and Care(AcEMC) Pavia 27100Italy

Syncope is a rather frequent condition,responsible for1.0%–1.5%of emergency department (ED) visits.[1]Even if the development of clinical guidelines has improved the ED management of syncope,[2]the hospitalization rate is still very high (up to 50%),especially compared with the incidence of short-term adverse events,which is11%globally,but decreases to less than 4%when events already diagnosed in the ED are excluded,[1]meaning that most patients will not benefit from admission.

关键词： globally department syncope