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A Quick and Practical Approach for Concept-design of Submerged Thin-walled Stiffened Cylinders

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Journal of Marine Science and Application 2022年第3期21卷 138-154页

作者： Tatiana Pais Marco Gaiotti cesare mario rizzo University of Genova Polytechnic SchoolDITENvia MontallegroI-16145 GenovaItaly

Goal based and limit state design is nowadays a well-established approach in many engineering *** construction rules started introducing such concepts since early ***,classification societies’rules do not provide hints on how to verify limit states and to determine the structural layout of submerged thin-walled stiffened cylinders,whose most prominent examples are ***,they generally offer guidance and prescriptive formulations to assess shell plating and stiffening *** marine structures are studied,designed and built up to carry payloads below the sea *** the concept-design stage,the maximum operating depth is the governing hull scantling *** dimensions are determined based on the analysis of operational *** study proposes a practical conceptdesign approach for conceptual submarine design,aimed at obtaining hull structures that maximize the payload capacity in terms of available internal volume by suitably adjusting structural layout and stiffening members’scantling,duly accounting for robustness and construction constraints as well as practical fabrication *** proposed scantling process highlights that there is no need of complex algorithms if sound engineering judgment is applied in setting down rationally the hull scantling problem.A systematic approach based on a computer-coded procedure developed on purpose was effectively implemented and satisfactorily applied in design practice.

关键词： Submarines Hull scantling Concept/preliminary design Limit state design Buckling Optimization Thin-walled cylinders

Three-Dimensional Fluid-Structure Interaction Case Study on Cubical Fluid Cavity with Flexible Bottom

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Journal of Marine Science and Application 2017年第4期16卷 382-394页

作者： Stefano Ghelardi cesare rizzo Diego Villa DITEN - Polo Navale Università degli Studi di Genova via Montallegro Genova 1 I-16145 Italy

In this paper, we report our study on a numerical fluid-structure interaction problem originally presented by Mok et al.(2001) in two dimensions and later studied in three dimensions by Valdés Vazquez(2007), Lombardi(2012), and Trimarchi(2012). We focus on a 3D test case in which we evaluated the sensitivity of several input parameters on the fluid and structural results. In particular, this analysis provides a starting point from which we can look deeper into specific aspects of these simulations and analyze more realistic cases, e.g., in sails design. In this study, using the commercial software ADINATM, we addressed a well-known unsteadiness problem comprising a square box representing the fluid domain with a flexible bottom modeled with structural shell elements. We compared data from previously published work whose authors used the same numerical approach, i.e., a partitioned approach coupling a finite volume solver(for the fluid domain) and a finite element solver(for the solid domain). Specifically, we established several benchmarks and made comparisons with respect to fluid and solid meshes, structural element types, and structural damping, as well as solution algorithms. Moreover, we compared our method with a monolithic finite element solution method. Our comparisons of new and old results provide an outline of best practices for such simulations.

关键词： fluid-structure interaction benchmark finite volume method finite element method partitioned monolithic ADINA^(TM)

The AMS measurement of ^236U at CIRCE

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Nuclear Science and Techniques 2017年第7期28卷 47-51页

作者： Yong-Jing Guan Hui-Juan Wang mario De cesare Filippo Terrasi Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science & Technology Guangxi University Nanning 530004 China Department of Diagnostic Methodologies and Measurement Techniques Italian Aerospace Research Centre (CIRA) 81043 Capua (CE) Italy INFN 80126 Naples Italy CIRCE Department of Mathematic and Physics Ⅱ University of Naples 81100 Caserta Italy

Accelerator mass spectrometry(AMS) is an ultrasensitive technique for measuring long-lived actinides,e.g.,^(236)U,^(237)Np and Pu *** order to improve the detection limit for actinides abundance,and to increase the detection efficiency in actinides AMS measurement,a 16-strip silicon detector was used to identify actinides at the Center for Isotopic Research on Cultural and Environmental heritage in Caserta,*** sensitivity of ^(236)U/^(238)U was 1×10^(-11) by special resolution and 5.0×10^(-12) by time *** pulse height defect of^(236)U in an ion-implanted silicon detector in the low-energy range with 17.26 MeV is presented.

关键词： AMS 测量锕系元素钚同位素硅探测器加速器质谱时间分辨率元素丰度

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^(236)U灵敏度的AMS测量

原子能科学技术 2010年第1期44卷 70-74页

作者：管永精 Filippo Terrasi mario De cesare Department of Environmental Sciences Ⅱ University of Naples 广西大学物理科学与工程技术学院广西南宁530004

长寿命放射性核素236U的半衰期为2.34×107a,主要来源是235U的中子俘获反应。加速器质谱法是目前测量236U灵敏度最高的方法。本工作利用意大利那不勒斯第二大学同位素研究环境与文化遗产中心的AMS装置测量236U的灵敏度,并分析了加速器... 详细信息

长寿命放射性核素236U的半衰期为2.34×107a,主要来源是235U的中子俘获反应。加速器质谱法是目前测量236U灵敏度最高的方法。本工作利用意大利那不勒斯第二大学同位素研究环境与文化遗产中心的AMS装置测量236U的灵敏度,并分析了加速器质谱测量236U时本底的可能来源。初步结果表明,236U的灵敏度(236U/238U原子比)为(2.29±0.13)×10-10。

关键词：加速器质谱 236U 同位素灵敏度

Comparison of laboratory and field electrical resistivity measurements of a gypsum rock for mining prospection applications

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International Journal of Mining Science and Technology 2019年第6期29卷 841-849页

作者： Chiara Caselle Sabrina Bonetto cesare Comina Department of Earth Science (DST) Torino University

Geophysical surveys are frequently applied in mining prospection to detect the presence and volume of ore bodies of different ***,in gypsum ore bodies exploitation,electrical resistivity measurements are usually the most used ***,it has been observed that different electrical resistivity values can be obtained depending on geometrical features and composition of ***,electrical resistivity of gypsum rocks depends on several parameters,such as gypsum purity,nature of secondary minerals,porosity,saturation and interstitial fluid *** and hydrogeological setting,in particular,were recognized as the most influencing *** conditions of gypsum rock masses are also very relevant for exploitability,safety conditions and economic feasibility and should be accurately known during the prospection and planning phases of the *** this work,a relationship between electrical resistivity and saturation degree of gypsum is *** possibility to estimate gypsum porosity with the use of this relationship is also *** reliability of laboratory measurements is finally verified in comparison with field and modelled resistivity *** reported results underline the potentiality of the proposed approach to obtain a reliable characterization of the studied ore body.

关键词： Gypsum rock Electrical resistivity Saturation Porosity Archie ERT Quarry

The neural bases of vitality forms

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National Science Review 2020年第1期7卷 202-213页

作者： Giuseppe Di cesare Marzio Gerbella Giacomo rizzolatti Cognitive Architecture for Collaborative Technologies Unit Italian Institute of Technology 2. Department of Medicine and Surgery Neuroscience Unit University of Parma Istituto di Neuroscienze Consiglio nazionale delle Ricerche

Unlike emotions, which are short-lasting events accompanied by viscero-motor responses, vitality forms are continuous internal states that modulate the motor behaviors of individuals and are devoid of the autonomic modifications that characterize real emotions. Despite the importance of vitality forms in social life, only recently have neurophysiological studies been devoted to this issue. The first part of this review describes f MRI experiments, showing that the dorso-central insula is activated during the execution, the perception and the imagination of arm actions endowed with different vitality forms as well as during the hearing and the production of speech conveying vitality forms. In the second part, we address the means by which the dorso-central insula modulates the networks for controlling action execution and how the sensory and interoceptive information is conveyed to this insular sector. Finally, we present behavioral data showing the importance of vitality forms in social interactions.

关键词： action observation social interactions emotions insula mirror mechanism

Data-based Fault Tolerant Control for Affine Nonlinear Systems Through Particle Swarm Optimized Neural Networks

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IEEE/CAA Journal of Automatica Sinica 2020年第4期7卷 954-964页

作者： Haowei Lin Bo Zhao Derong Liu cesare Alippi the School of Automation Guangdong University of TechnologyGuangzhou 510006China the School of Systems Science Beijing Normal UniversityBeijing 100875China the Dipartimento di Elettronica e Informazione Politecnico di MilanoMilano 20133Italy the Universita’Della Svizzera Italiana LuganoSwitzerland

In this paper, a data-based fault tolerant control(FTC) scheme is investigated for unknown continuous-time(CT)affine nonlinear systems with actuator faults. First, a neural network(NN) identifier based on particle swarm optimization(PSO) is constructed to model the unknown system dynamics. By utilizing the estimated system states, the particle swarm optimized critic neural network(PSOCNN) is employed to solve the Hamilton-Jacobi-Bellman equation(HJBE) more ***, a data-based FTC scheme, which consists of the NN identifier and the fault compensator, is proposed to achieve actuator fault tolerance. The stability of the closed-loop system under actuator faults is guaranteed by the Lyapunov stability theorem. Finally, simulations are provided to demonstrate the effectiveness of the developed method.

关键词： Adaptive dynamic programming(ADP) critic neural network data-based fault tolerant control(FTC) particle swarm optimization(PSO)

Steady-State Performance Evaluation of Linux TCPs versus TCP Wave over Leaky Satellite Links

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China Communications 2017年第3期14卷 17-30页

作者： Ahmed Abdelsalam cesare Roseti Francesco Zampognaro Department of Electronics Engineering University of Rome "Tor Vergata" Via del Politecnico 1 Rome 00133 Italy

Internet access is becoming even more heterogeneous, including different wireless backhauling links, with Ka-band satellites as a possible alternative. Since communication path is unknown a priori, adoption of PEP solutions to optimize TCP performance over satellite is discouraged to allow dynamic network reconfigurations. To opposite, an endto-end TCP performance evaluation on such a challenging scenario, with possible large latency and transmission losses, is herein considered of paramount importance. Several TCP variants exist to tackle different aspects of communication networks. In Linux, the different TCP congestion control schemes differ from the theoretical formulations and RFC specifications, introducing a varying set of optimizations and options. This aspect makes difficult to identify a standard/reference TCP version for the proposed scenario, while testing with the real protocol stacks is deemed necessary to obtain consistent results. In addition, an innovative end-to-end TCP, namely TCP Wave, is introduced to replace the traditional window-based transmission with a burst-based strategy, representing a valid alternative to Linux TCP. To offer a fair, realistic and comprehensive evaluation, we configured a simulation setup where different Linux TCPs can be run within ns-3 network simulator and compared with TCP Wave.

关键词： TCP satellite internet leaky channels Linux ns-3

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