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Publisher Correction to: Design and Simulation of a Crash Energy Absorption System Integrated with Magneto-Rheological Absorber

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Journal of Vibration engineering & Technologies 2021年第7期9卷 1807-1807页

作者： Archakam, Pavan Kumar Muthuswamy, Sreekumar Centre for AI IoT and Robotics Department of Mechanical Engineering Indian Institute of Information Technology Design and Manufacturing Kancheepuram India

A correction to this paper has been published: https://***/10.1007/s42417-021-00339-1

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Schottky barrier height engineering In β-Ga2O3 using SiO2interlayer dielectric

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arXiv 2020年

作者： Bhattacharyya, Arkka Ranga, Praneeth Saleh, Muad Roy, Saurav Scarpulla, Michael A. Lynn, Kelvin G. Krishnamoorthy, Sriram Department of Electrical and Computer Engineering University of Utah Salt Lake CityUT84112 United States Department of Electrical and Computer Engineering Department of Materials Science and Engineering University of Utah Salt Lake CityUT84112 United States Materials Science & Engineering Program Center for Materials Research Washington State University PullmanWA99164 United States Materials Science & Engineering Program Center for Materials Research School of Mechanical and Materials Engineering Department of Physics Washington State University PullmanWA99164 United States

This paper reports on the modulation of Schottky barrier heights (SBH) on three different orientations of βGa2O3 by insertion of an ultra-thin SiO2 dielectric interlayer at the metal-semiconductor junction, which can potentially lower the Fermi-level pinning (FLP) effect due to metal-induced gap states (MIGS). Pt and Ni metal-semiconductor (MS) and metal-interlayer-semiconductor (MIS) Schottky barrier diodes were fabricated on bulk n-type doped β-Ga2O3 single crystal substrates along the (010), (-201) and (100) orientations and were characterized by room temperature current-voltage (I-V) and capacitance-voltage (C-V) measurements. Pt MIS diodes exhibited 0.53 eV and 0.37 eV increment in SBH along the (010) and (-201) orientations respectively as compared to their respective MS counterparts. The highest SBH of 1.81 eV was achieved on the (010)-oriented MIS SBD using Pt metal. The MIS SBDs on (100)-oriented substrates exhibited a dramatic increment (>1.5×) in SBH as well as reduction in reverse leakage current. The use of thin dielectric interlayers can be an efficient experimental method to modulate SBH of metal/Ga2O3 junctions. Copyright © 2020, The Authors. All rights reserved.

关键词： Schottky barrier diodes

MRI-Based Patient-Specific Left Ventricular Model to Determine the Effects of Trabeculae Carneae on the Diastolic and Systolic Functions

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医用生物力学 2019年第A01期34卷 19-20页

作者： Fatemeh Fatemifar Marc Feldman Geoffrey Clarke Ender Finol Haichao Han Department of Mechanical Engineering and Biomedical Engineering Graduate Program University of Texas at San AntonioSan AntonioTX78249USA Department of Medicine 3.Research Imaging InstituteUniversity of Texas HealthScience Center at San AntonioTX78229USA

Introduction Trabeculae carneae are irregular structures that cover the endocardial surfaces of both ventricles of human heart and account for a significant portion of the ventricular ***,the role of trabeculae carneae in left ventricular(LV)function is not well *** reports suggested that trabeculae help squeeze blood from the apical region during systole[1].Our recent study suggests that trabeculae carneae hypertrophy and fibrosis contribute to increased LV stiffness in patients with diastolic heart failure,and severing free-running trabeculae carneae may improve diastolic compliance of the LV[2].Objective To understand the role of trabeculae carneae in the left ventricular diastolic and systolic functions using anatomically detailed patient-specific finite element models of the human ***(1)Image acquisition An explanted human heart was collected from a 63 year old female donor with a history of stroke and congestive heart failure within 24 hours postmortem from South Texas Blood and Tissue Center(San Antonio,TX).The heart was de-identified in accordance with Institutional Review Board(IRB)requirements and informed consent for research was obtained from the donor’s ***-dimensional MRI scanning was conducted on a 3T(128 MHz)MRI system(TIM Trio,Siemens Medical Solutions),comprised of a superconducting magnet with a 60 cm diameter accessible bore,when the heart was submerged in a saline filled plastic container.(2)Finite element analysis Three distinct LV models were derived from the MR *** first model was the intact trabeculated model(TM)which contained all trabeculae carneae and papillary *** high-resolution anatomically detailed 3D model of the LV was segmented from 2D MR images in DICOM format using Mimics(Materialise NV,Leuven,Belgium).The second model was the papillary model(PM),in which the papillary muscles remain intact but most of the trabeculae carneae were excluded in the smoothing *** third

关键词： EF MRI-Based Patient-Specific Trabeculae Carneae the Diastolic and Systolic F Model

Controlled tempering of lipid concentration and microbubble shrinkage as a possible mechanism for fine-tuning microbubble size and shell properties

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arXiv 2023年

作者： Zalloum, Intesar O. Sojahrood, Amin Jafari Paknahad, Ali A. Kolios, Michael C. Tsai, Scott S.H. Karshafian, Raffi Department of Physics Toronto Metropolitan University TorontoONM5B 2K3 Canada Department of Mechanical and Industrial Engineering Toronto Metropolitan University 350 Victoria Street TorontoONM5B 2K3 Canada A Partnership Between Toronto Metropolitan University St. Michael's Hospital 209 Victoria Street TorontoONM5B 1T8 Canada Keenan Research Centre for Biomedical Science Unity Health Toronto 209 Victoria Street TorontoONM5B 1W8 Canada Graduate Program in Biomedical Engineering Toronto Metropolitan University 350 Victoria Street TorontoONM5B 2K3 Canada

The acoustic response of microbubbles (MBs) depends on their resonance frequency, which is dependent on MB size and shell properties. Monodisperse MBs with tunable shell properties are thus desirable for optimizing and controlling MB behavior in acoustics applications. By utilizing a novel microfluidic method that uses lipid concentration to control MB shrinkage, we generate monodisperse MBs of four different initial diameters at three lipid concentrations (5.6, 10.0, and 16.0 mg/mL) in the aqueous phase. Following shrinkage, we measure MB resonance frequency and determine its shell stiffness and viscosity. The study demonstrates that we can generate monodisperse MBs of specific sizes and tunable shell properties by controlling MB initial diameter and aqueous phase lipid concentration. Our results indicate that the resonance frequency increases by 180-210% with increasing lipid concentration (from 5.6 to 16.0 mg/mL) while bubble diameter is kept constant. Additionally, we find that the resonance frequency decreases by 260-300% with increasing MB final diameter (from 5 to 12 μm), while lipid concentration is held constant. For example, our results depict that the resonance frequency increases by ~195% with increasing lipid concentration from 5.6 to 16.0 mg/mL, for ~11 μm final diameter MBs. Additionally, we find that the resonance frequency decreases by ~275% with increasing MB final diameter from 5 to 12 μm, when we use a lipid concentration of 5.6 mg/mL. We also determine that MB shell viscosity and stiffness increase with increasing lipid concentration and MB final diameter, and the level of change depends on the degree of shrinkage experienced by MB. Specifically, we find that by increasing the concentration of lipids from 5.6 to 16.0 mg/mL, the shell stiffness and viscosity of ~11 μm final diameter MBs increase by ~400% and ~200 %, respectively. This study demonstrates the feasibility of fine-tuning the MB acoustic response to ultrasound by tailoring MB initial

关键词： Shrinkage

Passive Quadrupedal Gait Synchronization for Extra Robotic Legs Using a Dynamically Coupled Double Rimless Wheel Model

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arXiv 2020年

作者： Gonzalez, Daniel J. Harry Asada, H. Robotics Research Center Department of Electrical Engineering and Computer Science United States Military Academy West PointNY10996 United States d’Arbeloff Laboratory for Information Systems and Technology Department of Mechanical Engineering Massachusetts Institute of Technology CambridgeMA02139 United States

The Extra Robotic Legs (XRL) system is a robotic augmentation worn by a human operator consisting of two articulated robot legs that walk with the operator and help bear a heavy backpack payload. It is desirable for the Human-XRL quadruped system to walk with the rear legs lead the front by 25% of the gait period, minimizing the energy lost from foot impacts while maximizing balance stability. Unlike quadrupedal robots, the XRL cannot command the human’s limbs to coordinate quadrupedal locomotion. Using a pair of Rimless Wheel models, it is shown that the systems coupled with a spring and damper converge to the desired 25% phase difference. A Poincaré return map was generated using numerical simulation to examine the convergence properties to different coupler design parameters, and initial conditions. The Dynamically Coupled Double Rimless Wheel system was physically realized with a spring and dashpot chosen from the theoretical results, and initial experiments indicate that the desired synchronization properties may be achieved within several steps using this set of passive components alone. Copyright © 2020, The Authors. All rights reserved.

关键词： Exoskeleton (robotics)

Numerical Investigation Against Laboratory Experiment: An Overview of Damage and Wind Loads on Structural Design

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Procedia Structural Integrity 2020年 27卷 6-13页

作者： Aldias Bahatmaka Dong-Joon Kim Aditya Rio Prabowo Daewoo Shipbuilding and Marine Engineering (DSME).Co.Ltd Okpo 53305 South Korea Interdisciplinary Program of Marine Design Convergence Pukyong National University Busan 48513 South Korea Department of Naval Architecture and Marine Systems Engineering Pukyong National University Busan 48513 South Korea Department of Mechanical Engineering Universitas Sebelas Maret Surakarta 57126 Indonesia

The numerical approach is being used against experimental and solves engineering problems. In the engineering design, the structural and load analysis are a part of an important thing to show the effect of geometrical or the structure design. The main purpose is to review the influence of deckhouse height on the flow around the funnel and aft ship structure. In this review study, the fluid-structure and 3D steady RANS CFD are used to validate the result of simulations. Several aspects of the numerical approach, such as turbulence modeling, boundary conditions, inlet velocity, and pressure outlet to simulate wind load in CFD, ground surface roughness, and quantification of wind loads by computational fluid-structure and computational fluid dynamics (CFD) are summarized. A benchmarking study of the numerical approach against the experiment is emphasized. A comparative study among the numerical prediction on the wind tunnel demonstrated good agreement and satisfaction. Moreover, by numerical approach could handle the accurate results and show how the response to the ship structure that makes the dynamic interaction during wind loads events.

关键词： Fluid Structure Wind Loads Numerical Approach CFD Experimental

Three-dimensional kinematic metamaterial with tuneable directional permeability

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arXiv 2021年

作者： Yang, Yunfang Maiolino, Perla Chen, Yan You, Zhong Department of Engineering Science University of Oxford Parks Road OxfordOX1 3PJ United Kingdom Oxford Robotics Institute University of Oxford Parks Road OxfordOX1 3PJ United Kingdom Key Laboratory of Mechanism Theory Equipment Design of Ministry of Education Tianjin University Tianjin300072 China School of Mechanical Engineering Tianjin University Tianjin University Tianjin300072 China

Reconfigurable metamaterials are constructed from tessellation of deformable modules that give rise to a set of tuneable properties. To date, most research focuses on metamaterials that morph between final configurations along a single deformation path. Multi-pathway metamaterials that can transform into several different shapes according to various external stimuli are rare. Here we propose a kinematic based metamaterial with multiple predefined deformation paths. The inherent kinematic bifurcations of the deformable unit cells enable the metamaterial to switch among different paths under simple stimuli at one particular configuration, resulting in the enhancement of reconfigurability. The metamaterials demonstrated in this paper can provide multiple open channels in different orthogonal directions, making them suitable for multifunctional applications such as tuneable filters and reconfigurable wave guiding materials. © 2021, CC BY.

关键词： Metamaterials

From farm to land: Characteristics of biochar for agricultural purposes 27th

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From farm to land: Characteristics of biochar for agricultur...

27th European Biomass Conference and Exhibition, EUBCE 2019

作者： de Souza, Débora Machado Kappler, Genyr Bueno, Andriele Brizolla Silva, Jenifer Lima da Modolo, Regina Célia Espinosa Moraes, Carlos Alberto Mendes Tarelho, Luís António da Cruz Brehm, Feliciane Andrade Graduate Program in Mechanical Engineering University of Vale do Rio dos Sinos-UNISINOS São LeopoldoRS93022-000 Brazil Graduate Program in Civil Engineering UNISINOS Portugal Undergraduate students in Environmental Engineering UNISINOS Portugal Department of Environment and Planning/CESAM University of Aveiro Aveiro3810193 Portugal

Agribusiness has a significant role in the life of billions of people and is an essential component in the economy of many countries. In Brazil agribusiness is one of the most prominent components in the economy and it accounted for 21% of the Gross Domestic Product in 2016. The soil is a non-renewable resource, and its adequate management becomes increasingly relevant to maintain its fertility and ensure the production of food to supply the population and industries in the food sector. The use of chemical fertilizers and mineral correctives is a requirement of modern agriculture and is practically indispensable for the management of crops. However, it is not an environmental friendly management technique method and may cause economic losses. On the other hand, there is an acknowledgment of nature-based solutions that contribute to improving soil quality while reducing the environmental burden from modern agrosystem. The choice for utilizing rice husk as biomass feedstock in this research is based on the current reality of Brazil, where there is an annual production of approximately 11.7 million tons of rice, from which around 20% become residue. Considering that Brazil has large areas of cultivation and that agriculture residues are still underutilized, the objective of this study was to evaluate the influence of biochar obtained from rice husk in the fertility of soil based on two parameters, which are porosity and water holding capacity. The conversion of agricultural residues into soil conditioners, i.e., closing the cycle of nutrients from farm to land, is an interesting option for sustainable resource management, which should also encompass the environmental, social and economic aspects. © 2019 ETA-Florence Renewable Energies.

关键词： Agriculture Biochar Biomass Fertilizers

A method for recognition of dynamic hand gestures based on wrist tendon sounds 22

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A method for recognition of dynamic hand gestures based on w...

22nd IEEE International Conference on E-Health Networking, Application and Services, HEALTHCOM 2020

作者： He, Bailin Wang, Can Wang, Hao Li, Mengyao Duan, Shengcai Wu, Xinyu Guangdong Provincial Key Laboratory of Robotics and Intelligent System Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen518055 China CAS Key Laboratory of Human-Machine Intelligence-Synergy Systems Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen518055 China University of Chinese Academy of Sciences Beijing100049 China Department of Mechanical and Automation Engineering The Chinese University of Hong Kong Hong Kong Samsung Electronics Guangdong-Hong Kong-Macao Joint Laboratory of Human-Machine Intelligence-Synergy Systems Shenzhen Institutes of Advanced Technology Chinese Academy of Sciences Shenzhen518055 China

ISBN: (纸本)9781728162676

Hand gesture recognition are widely applied in game industry and rehabilitation engineering. Some recognition methods based on physiological data are attracting attention. In this paper, a novel method for dynamic hand gesture recognition based on sounds of wrist tendon is proposed. Bone conduction sensors which automatically filter the ambient noise is utilized to collect the wrist tendon sounds of three types of dynamic hand gestures. Continuous Wavelet Transform(CWT) is utilized extract the features of sounds and Support Vector Machine(SVM) is utilized to train the classifier model. Five healthy subjects participated the experiment and the average test accuracy of three classes achieves 92.33%. The proposed method provides an effective perspective for hand gesture recognition. © 2021 IEEE.

关键词： Support vector machines