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Analysis of suitable geometrical parameters for designing a tendon-driven under-actuated mechanical finger

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Frontiers of Mechanical Engineering 2016年第2期11卷 184-194页

作者： Francesco PENTA Cesare ROSSI Sergio savino Department of Industrial Engineering University of Naples 'FedericoII' Naples 80125 Italy

This study aims to optimize the geometrical parameters of an under-actuated mechanical finger by conducting a theoretical analysis of these parameters. The finger is actuated by a flexion tendon and an extension tendon. The considered parameters are the tendon guide positions with respect to the hinges. By applying such an optimization, the correct kinematical and dynamical behavior of the closing cycle of the finger can be obtained. The results of this study are useful for avoiding the snap- through and the single joint hyperflexion, which are the two breakdowns most frequently observed during experi- mentation on prototypes. Diagrams are established to identify the optimum values for the tendon guides position of a finger with specified dimensions. The findings of this study can serve as guide for future finger design.

关键词： tendon-driven fingers mechanical fingerdesign under-actuated mechanical systems

A data analytics-based tool for the detection and diagnosis of anomalous daily energy patterns in buildings

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Building Simulation 2021年第1期14卷 131-147页

作者： Marco savino Piscitelli Silvio Brandi Alfonso Capozzoli Fu Xiao Department of Energy“Galileo Ferraris” TEBE research groupPolitecnico di TorinoTurinItaly Department of Building Services Engineering The Hong Kong Polytechnic UniversityHong KongChina

In this paper,a tool for the detection and diagnosis of anomalous electrical daily energy patterns relative to a transformer substation of a university campus was developed and *** an innovative pattern recognition analysis consisting in a multi-step clustering process,six clusters of anomalous daily load profiles were identified and isolated in two-year historical data of total electrical energy *** infrequent electrical load profiles were found to be strongly affected,in terms of both shape and magnitude,by the energy consumption behaviour related to the heating/cooling mechanical ***,a fault-free predictive model,which uses artificial neural network(ANN)in combination with a Regression Tree,was developed to detect anomalous trends of the electrical energy *** model was able to detect the 93.7%of the anomalous profiles and only the 5%of fault-free days were wrongly predicted as ***,a diagnosis phase was conceived and validated with a testing data set.A number of daily abnormal load profiles were detected and compared with the centroids of the anomalous clusters identified in the pattern-recognition *** work led to the development of a flexible intelligent tool useful for operating a continuous commissioning of the campus facilities.

关键词： anomaly detection data analytics energy management pattern recognition prediction models

Windmills： Ancestors of the wind power generation

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Frontiers of Mechanical Engineering 2017年第3期12卷 389-396页

作者： Cesare ROSSI Flavio RUSSO Sergio savino Department of Industrial Engineering University of Naples "Federico Ⅱ" via Claudio Naples 80125 Italy Consultant of Ufficio Storico Stato Maggiore Esercito Torre Del Greco 80059 Italy

A brief description of the windmills from the second millennium BC to the Renaissance is presented. This survey is a part of several studies conducted by the authors on technology in the ancient world. The windmills are the first motor, other than human muscles, and are the ancestors of the modem wind turbines. Some authors＇ virtual reconstructions of old windmills are also presented. The paper shows that the operating principle of many modem machines had already been conceived in the ancient times by using a technology that was more advanced than expected, but with two main differences, as follows： Similar tasks were accomplished by using much less energy; and the environmental impact was nil or very low. Modem designers should sometimes consider simplicity rather than the use of a large amount of energy.

关键词： windmills ancient machines history of windmill

Leveraging graph convolutional networks for semi-supervised fault diagnosis of HVAC systems in data-scarce contexts

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建筑模拟(英文) 2023年第8期16卷 1499-1517页

作者： Cheng Fan Yiwen Lin Marco savino Piscitelli Roberto Chiosa Huilong Wang Alfonso Capozzoli Yuanyuan Ma Key Laboratory for Resilient Infrastructures of Coastal Cities Ministry of EducationShenzhen UniversityShenzhenChina Sino-Australia Joint Research Center in BIM and Smart Construction Shenzhen UniversityShenzhenChina College of Civil and Transportation Engineering Shenzhen UniversityShenzhenChina Department of Energy TEBE research groupBAEDA LabPolitecnico di TorinoTorinoItaly

The continuous accumulation of operational data has provided an ideal platform to devise and implement customized data analytics for smart HVAC fault detection and *** practice,the potentials of advanced supervised learning algorithms have not been fully realized due to the lack of sufficient labeled *** tackle such data challenges,this study proposes a graph neural network-based approach to effectively utilizing both labeled and unlabeled operational data for optimum *** specifically,a graph generation method is proposed to transform tabular building operational data into association graphs,based on which graph convolutions are performed to derive useful insights for fault *** experiments have been designed to evaluate the values of the methods *** datasets on HVAC air-side operations have been used to ensure the generalizability of results *** data scenarios,which vary in training data amounts and imbalance ratios,have been created to comprehensively quantify behavioral patterns of representative graph convolution networks and their *** research results indicate that graph neural networks can effectively leverage associations among labeled and unlabeled data samples to achieve an increase of 2.86%–7.30%in fault classification accuracies,providing a novel and promising solution for smart building management.

关键词： fault detection and diagnosis graph convolutional networks semi-supervised learning HVAC systems machine learning

Consensus on Intervals of Communication Delay

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International Journal of Automation and computing 2018年第1期15卷 13-24页

作者： Heitor J.savino Fernando O.Souza Luciano C.A.Pimenta Graduate Program in Electrical Engineering Federal University of Minas Gerais Institute of Computing Federal University of Alagoas Department of Electronic Engineering Federal University of Minas Gerais

This paper brings out a structured methodology for identifying intervals of communication time-delay where consensus in directed networks of multiple agents with high-order integrator dynamics is achieved. It is built upon the stability analysis of a transformed consensus problem which preserves all the nonzero eigenvalues of the Laplacian matrix of the associated communication topology graph. It is shown that networks of agents with first-order integrator dynamics can be brought to consensus independently of communication delay, on the other hand, for agents with second-order integrator dynamics, the consensus is achieved independently of communication delay only if certain conditions axe satisfied. Conversely, if such conditions axe not satisfied, it is shown how to compute the intervals of communication delay where multiple agents with second-order or higher-order can be brought to consensus. The paper is ended by showing an interesting example of a network of agents with second-order integrator dynamics which is consensable on the first time-delay interval, but as the time-delay increases, it loses consensability on the second time-delay interval, then it becomes consensable again on the third time-delay interval, and finally it does not achieve consensus any more on the fourth time-delay interval. This example shows the importance of analyzing consensus with time-delay in different intervals.

关键词： Time delay systems multi-agent systems consensus communication delay roots location.

Ancient road transport devices： Developments from the Bronze Age to the Roman Empire

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Frontiers of Mechanical Engineering 2016年第1期11卷 12-25页

作者： Cesare ROSSI Thomas G. CHONDROS Kypros F. MILIDONIS Sergio savino Flavio RUSSO Department of Industrial Engineering University of Naples 'Federico II' Naples 80125 Italy Mechanical Engineering & Aeronautics Department University of Patras Patras 26500 Greece USSME Consultant via Lamaria 137 Torte del Greco Napoli Italy

The development of transportation systems has significantly enhanced the welfare and modernization of society. Wooden vehicles pulled by animals have been used for land transportation since the early Bronze Age. Whole-body gharries with rigid wheels pulled by oxen appeared in Crete by 2000 BC or earlier. Horses originating from the East were depicted in early Cretan seal-rings of the same period. The two-wheeled horse- drawn chariot was one of the most important inventions in history. This vehicle provided humanity its first concept of personal transport and was the key technology of war for 2000 years. Chariots of Mycenaean and Archaic Greece with light and flexible four-spoked wheels acting as spring suspensions were depicted in vase paintings. The development of this vehicle incorporated the seeds of a primitive design activity and was important for engineering. The Trojan horse since 1194 BC and the helepolis since 700 BC were the first known machines on a wheeled base transported by horses or self-powered. Ancient engineers invented bearings lubricated with fat, and Romans introduced the ancestors of ball bearings for their wagons and carts. The historic evolution of wheeled transportation systems, along with early traction, suspension, and braking systems, is presented in this paper. Analytical and numerical methods are incorporated to analyze the most conceivable loading situations of typically reconstructed wheeled transportation systems in ancient times. Traction requirements both for horse-driven machines and the power for internal motors are also analyzed. This study can serve as a basis for further development of detailed reconstruction of transportation systems in antiquity.

关键词： transportation wheel spoke cart axle bearing

Correlation between impedance spectroscopy and bubble-induced mass transport in the electrochemical reduction of carbon dioxide

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Journal of Energy Chemistry 2022年第4期31卷 500-507页

作者： Stefania Lettieri Juqin Zeng M.Amin Farkhondehfal Umberto savino Marco Fontana Candido F.Pirri Adriano Sacco Center for Sustainable Future Technologies@Polito Istituto Italiano di TecnologiaVia Livorno 6010144 TorinoItaly Department of Applied Science and Technology Politecnico di TorinoCorso Duca degli Abruzzi 2410129 TorinoItaly

In the electrochemical conversion of carbon dioxide, high currents need to be employed to obtain large production rates, thus implying that mass transport of reactants and products is of crucial *** aspect can be investigated by employing a model that depicts the local environment for the reduction reactions. Simultaneously, electrochemical impedance spectroscopy, despite being a versatile technique, has rarely been adopted for studying the mass transport features during the carbon dioxide(CO_(2))electroreduction. In this work, this aspect is deeply analyzed by correlating the results of impedance spectroscopy characterization with those obtained by a bubble-induced mass transport modeling under controlled diffusion conditions on a gold rotating disk electrode. The effects of potential and rotation rate on the local environment are also clarified. In particular, it has been found that CO_(2) depletion occurs at high kinetics when the rotation is absent, giving rise to an increment of the competing hydrogen evolution reaction. This feature reflects in an enlargement of the diffusion resistance, which overcomes the charge transport one.

关键词： Carbon dioxide conversion Impedance spectroscopy Mass transport Modeling Rotating disk electrode

Clinical expression of insulin resistance in hepatitis C and B virus-related chronic hepatitis:Differences and similarities

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World Journal of Gastroenterology 2009年第4期15卷 462-466页

作者： Marcello Persico Mario Masarone Vincenzo La Mura Eliana Persico Francesco Moschella Monica Svelto savino Bruno Roberto Torella Internal Medicine and Hepatology Unit Second University of Naples Internal Medicine and Hepatology Unit Fatebenefratelli Hospital

AIM： To investigate the prevalence of the clinical pa- rameters of insulin resistance and diabetes in patients affected by chronic hepatitis C （CHC） or chronic hepa- titis B （CHB）. METHODS： We retrospectively evaluated 852 consec- utive patients （726 CHC and 126 CriB） who had under- gone liver biopsy. We recorded age, sex, ALT, type 2 diabetes and/or metabolic syndrome （MS）, body mass index （BMI）, and apparent disease duration （ADD）. RESULTS： Age, ADD, BMI, prevalence of MS and diabetes in patients with mild/moderate liver fibrosis were significantly higher in CHC. However, the degree of steatosis and liver fibrosis evaluated in liver biop- sies did not differ between CHC and CHB patients. At multivariate analysis, age, sex, BMI, ALT and diabetes were independent risk factors for liver fibrosis in CHC, whereas only age was related to liver fibrosis in CHB. We also evaluated the association between significant steatosis （〉 30%） and age, sex, BMI, diabetes, MS and liver fibrosis. Diabetes, BMI and liver fibrosis were associated with steatosis 〉 30% in CHC, whereas only age and BMI were related to steatosis in CriB. CONCLUSION： These data may indicate that hepatitis C virus infection is a risk factor for insulin resistance.

关键词： Insulin resistance Diabetes Metabolicsyndrome Hepatitis C virus Hepatitis B virus

Propulsion tests on ultra-high-temperature ceramic matrix composites for reusable rocket nozzles

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Journal of Advanced Ceramics 2023年第7期12卷 1345-1360页

作者： Diletta Sciti Antonio Vinci Luca Zoli Pietro Galizia Simone Failla Stefano Mungiguerra Giuseppe D.Di Martino Anselmo Cecere Raffaele savino Institute of Science Technology and Sustainability for Ceramics-National Research CouncilFaenza 48018Italy Department of Industrial Engineering University of Naples Federico IINaples 80125Italy

Ultra-high-temperature ceramic matrix composites(UHTCMCs)based on a ZrB_(2)/SiC matrix have been investigated for the fabrication of reusable nozzles for *** de Laval nozzle prototypes,obtained by sintering with either hot pressing(HP)or spark plasma sintering(SPS),were tested 2-3 times in a hybrid rocket motor for proving *** were extracted after oxidation tests to study the microstructural changes and oxidative and thermomechanical stresses induced by the repeated *** to a reference graphite nozzle,no measurable erosion was observed for the UHTCMC-based *** oxidation mechanism consisted in the formation of a ZrO_(2)intermediate layer,with a liquid silicon oxide(SiO_(2))layer on the surface that was displaced by the action of the gas flux towards the divergent part of the nozzle,protecting it from further *** specimens obtained by HP and SPS displayed similar performance,with very slight differences,which were attributed to small changes in *** tests demonstrated the capability of complex-shaped prototypes made of the developed UHTCMCs to survive repeated exposure to environments representative of a realistic space propulsion application,for overall operating time up to 30 s,without any failure nor measurable erosion,making a promising step towards the development of reusable rocket components.

关键词： ultra-high-temperature ceramics(UHTCs) ceramic matrix composites(CMCs) propulsion oxidation resistance nozzle prototypes