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Ultra-light hybrid composite car door design & rapid manufacture 5

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Ultra-light hybrid composite car door design & rapid manufac...

5th Annual Composites and Advanced materials Expo, CAMX 2018

作者： Gravelle, Nathan P. Allen, Christian Keyes, Allen Heider, Dirk Tierney, John Gillespie, J.W. TPI Composites Inc 373 Market Street WarrenRI02885 United States NewarkDE19716 United States Department of Electrical and Computer Engineering NewarkDE19716 United States Department of Materials Science and Engineering NewarkDE19716 United States Department of Civil and Environmental Engineering NewarkDE19716 United States Department of Mechanical Engineering NewarkDE19716 United States

TPI Composites with partners Hexion, Krauss Maffei, and the University of Delaware, have completed the design of an advanced composite driver-side commercial passenger car door. The project goals for this component include a 42.5% weight savings and less than a $5 cost increase for every pound of weight saved in the door. The program includes the development of manufacturing processes, fabrication of tooling and component molding and assembly of multiple doors for demonstration of manufacturing rate, cost and suitability for use in a full-scale automotive application. These door components will be subject to the same static and dynamic proof tests, and Federal Motor Vehicle Safety Standard (FMVSS) -214 side impact testing, as the existing metallic door to validate equality. To date, the project team has begun manufacture of prototype parts. The main door components are manufactured using both High Pressure Resin Transfer Molding (HP-RTM) and Liquid Compression Molding (LCM). These highly automated process technologies, along with suitable resin formulations, enable composites to support high volume automotive production. It is this automated low cycle-time solution that enable composites to become a viable alternative to metals in high rate automotive manufacturing. © 2018. Used by CAMX The Composites and Advanced materials Expo. CAMX Conference Proceedings. Dallas, TX.

关键词： Resins

Lithography-free kirchhoff’s metasurfaces

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arXiv 2020年

作者： Kumagai, Takuhiro Naoki, T.O. Balčytis, Armandas Seniutinas, Gediminas Juodkazis, Saulius Nishijima, Yoshiaki Department of Physics Electrical and Computer Engineering Graduate School of Engineering Yokohama National University 79-5 Tokiwadai Hodogaya-ku Yokohama240-8501 Japan Center for Physical Sciences and Technology A. Goštauto 9 VilniusLT-01108 Lithuania School of Science Swinburne University of Technology HawthornVIC3122 Australia Institute of Advanced Sciences Yokohama National University 79-5 Tokiwadai Hodogaya-ku Yokohama240-8501 Japan School of Materials and Chemical Technology Tokyo Institute of Technology 2-12-1 Ookayama Meguro-ku Tokyo152-8550 Japan

Lithography-free metasurfaces composed of a nano-layered stack of materials are attractive not only due to their optical properties but also by virtue of fabrication simplicity and cost reduction of devices based on such structures. We demonstrate a multi-layer metasurface with engineered electromagnetic absorption in the mid-infrared (MIR) wavelength range. Characterization of thin SiO2 and Si films sandwiched between two Au layers by way of experimental absorption and thermal radiation measurements as well as finite difference time domain (FDTD) numerical simulations is presented. Comparison of experimental and simulation data of optical properties of multilayer metasurfaces show guidelines for the absorber/emitter applications. Copyright © 2020, The Authors. All rights reserved.

关键词： Optical properties

Graphene induced large shift of surface plasmon resonances of gold films: Effective medium theory for atomically thin materials

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arXiv 2019年

作者： Alam, Md Kamrul Niu, Chao Wang, Yanan Wang, Wei Li, Yang Dai, Chong Tong, Tian Shan, Xiaonan Charlson, Earl Pei, Steven Kong, Xiang-Tian Hu, Yandi Belyanin, Alexey Stein, Gila Liu, Zhaoping Hu, Jonathan Wang, Zhiming Bao, Jiming Materials Science and Engineering University of Houston HoustonTX77204 United States Department of Electrical & Computer Engineering Baylor University WacoTX76798 United States Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Chengdu Sichuan610054 China Department of Electrical and Computer Engineering University of Houston HoustonTX77204 United States Ningbo Institute of Materials Technology & Engineering Chinese Academy of Sciences Ningbo Zhejiang315201 China Key Laboratory of Graphene Technologies and Applications of Zhejiang Province Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Ningbo Zhejiang315201 China Department of Civil and Environmental Engineering University of Houston Houston TX77204 United States Department of Physics & Astronomy Texas A&M University College StationTX77843 United States Chemical and Biomolecular Engineering University of Tennessee KnoxvilleTN37996 United States State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Chengdu Sichuan610054 China

Despite successful modeling of graphene as a 0.34-nm thick optical film synthesized by exfoliation or chemical vapor deposition (CVD), graphene induced shift of surface plasmon resonance (SPR) of gold films has remained controversial. Here we report the resolution of this controversy by developing a clean CVD graphene transfer method and extending Maxwell-Garnet effective medium theory (EMT) to 2D materials. A SPR shift of 0.24ºis obtained and it agrees well with 2D EMT in which wrinkled graphene is treated as a 3-nm graphene/air layered composite, in agreement with the average roughness measured by atomic force microscope. Because the anisotropic built-in boundary condition of 2D EMT is compatible with graphene’s optical anisotropy, graphene can be modelled as a film thicker than 0.34-nm without changing its optical property;however, its actual roughness, i.e., effective thickness will significantly alter its response to strong out-of-plane fields, leading to a larger SPR shift. Copyright © 2019, The Authors. All rights reserved.

关键词： Surface plasmon resonance

Characterization of TOF-PET detectors for a second generation radiofrequency-penetrable PET insert for simultaneous PET/MRI

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Characterization of TOF-PET detectors for a second generatio...

IEEE Symposium on Nuclear science (NSS/MIC)

作者： Qian Dong Brian J. Lee Chen-Ming Chang Ilaria Sacco Ronald D. Watkins Peter Fischer Emily Anaya Craig S. Levin Departments of Electrical Engineering and Radiology Stanford University Stanford CA USA Departments of Mechanical Engineering and Radiology Stanford University Stanford CA USA Departments of Applied Physics and Radiology Stanford University Stanford CA USA Department of Radiology Stanford University Stanford CA USA Department of Computer Science Heidelberg University Mannheim Germany Departments of Radiology Electrical Engineering Bioengineering and Physics Stanford University and Molecular Imaging Program at Stanford (MIPS) Stanford CA USA

ISBN: (数字)9781728141640

ISBN: (纸本)9781728141657

Simultaneous PET/MRI combines two powerful and complementary modalities, providing multiparametric information to assess the anatomic as well as biochemical basis of disease. However, the high cost of the current commercial integrated PET/MRI systems limit the long-term potential, accessibility, and availability of PET/MRI. A portable PET insert provides a cost- effective alternative to achieve simultaneous PET/MRI for the sites that are already equipped with MR systems. Therefore, we are developing a radiofrequency (RF)-penetrable MR-compatible time-of-flight (TOF)-PET insert that can acquire simultaneous PET/MR data using the MR systems built-in body coil for RF transmission. In this study, we characterized performance of two detector modules in the MR bore under four different MRI conditions: B 0 only, echo planar imaging (EPI), gradient echo (GRE), and fast spin echo (FSE), each running for 15 minutes. The one-hour study results for coincidence timing resolution, energy resolution, coincidence count rate and ASIC chip temperature of two detector modules demonstrate the PET performance stability as well as the MR compatibility of the PET detectors under different MRI sequences. The global coincidence timing and energy resolution achieved was 264.21 ± 4.82 ps FWHM and 13.66 ± 0.08 % FWHM, respectively.

关键词： Detectors Clocks Energy resolution Magnetic resonance imaging Timing Positron emission tomography Radio frequency

An Evaluation of LoRa Communication Range in Urban and Forest Areas: A Case Study in Brazil and Portugal

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An Evaluation of LoRa Communication Range in Urban and Fores...

International Conference and Workshop on Computing and Communication (IEMCON)

作者： Mariana Rodrigues Villarim João Vitor Holanda de Luna Douglas de Farias Medeiros Renata Imaculada Soares Pereira Cleonilson Protasio de Souza Orlando Baiocchi Francisco Cipriano da Cunha Martins Postgraduation Program of Electr. Eng. Federal University of Paraíba João Pessoa Brazil Department of Electrical Engineering Federal University of Paraíba João Pessoa Brazil School of Engineering and Technology University of Washington Tacoma Tacoma WA USA Department of Computer Science University of Azores São Miguel Azores Portugal

Due to its particular features, LoRa is gaining more and more attention from industry and academia because it tries to combine long communication range, low-power consumption, and low-data rate application. A very important feature observed on LoRa is that it is highly robust and reliable. Due to this, LoRa is being applied in many IoT solutions in urban environment, but on hard natural environments like dense forest, near river sides, lakes and mangroves, more studies need to be carried out in order to evaluate the its quality. This paper describes experimental studies carried out to measure LoRa communication range and Received Signal Strength Indicator (RSSI), both in natural and urban environments. The experiments took place in two different places of the world, one in the northern hemisphere and another in the southern hemisphere: on the Portuguese archipelago of the Azores (in SãoMiguel Island) and in the city of João Pessoa in Northeast of Brazil, respectively. As a result, we observed that LoRa is very robust in dense urban environments, where it was possible to established long distance connections (approximately 2.1 km). However, the results were inconclusive in forest environments, because in the Azores, the LoRa connection ranged about 800 m thought the forest/lake, while in Brazil it was about 230 m.

关键词： Forestry Lakes Chirp Urban areas Frequency modulation Internet of Things Wireless communication

Spoof-Fluid-Spoof Acoustic Waveguide and its Applications for Sound Manipulation

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Physical Review Applied 2019年第5期12卷 054014-054014页

作者： Norbert Cselyuszka Andrea Alù Nikolina Janković BioSense Institute University of Novi Sad Novi Sad Serbia Silicon Austria Labs Sensor System Microsystem Technologies Villach Austria Department of Electrical and Computer Engineering The University of Texas at Austin Austin Texas 78712 USA Photonics Initiative Advanced Science Research Center City University of New York New York New York 10031 USA Physics Program Graduate Center City University of New York New York New York 10026 USA Department of Electrical Engineering City College of New York New York New York 10031 USA

We explore the implementation of a spoof–fluid-spoof (SFS) acoustic waveguide, which is the acoustic analogue of a metal-insulator–metal waveguide in plasmonics. The proposed structure consists of two corrugated rigid surfaces separated by a fluid layer. The properties of the guided acoustic modes between corrugated rigid parallel plates are analytically and numerically studied by deriving their dispersion relation and through a careful analysis of symmetric and antisymmetric modes supported by this structure. Similar to plasmonic waveguides, it is shown that the dispersion relation of the proposed SFS acoustic waveguide, and the supported group and phase velocities, can be largely controlled by changes in the geometrical parameters of the waveguide, opening the possibility for application of this technology for acoustic delay lines, modulators, and sensors. The analytical and numerical results are validated through experiments in a controlled environment.

关键词： Acoustic measurements Acoustic metamaterials Acoustic modeling Acoustic wave phenomena Plasmonics Surface plasmon polariton Waveguides Surface acoustic wave

QU-BraTS: MICCAI BraTS 2020 Challenge on Quantifying Uncertainty in Brain Tumor Segmentation - Analysis of Ranking Scores and Benchmarking Results

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arXiv 2021年

作者： Mehta, Raghav Filos, Angelos Baid, Ujjwal Sako, Chiharu McKinley, Richard Rebsamen, Michael Dätwyler, Katrin Meier, Raphael Radojewski, Piotr Murugesan, Gowtham Krishnan Nalawade, Sahil Ganesh, Chandan Wagner, Ben Yu, Fang F. Fei, Baowei Madhuranthakam, Ananth J. Maldjian, Joseph A. Daza, Laura Gómez, Catalina Arbeláez, Pablo Dai, Chengliang Wang, Shuo Reynaud, Hadrien Mo, Yuanhan Angelini, Elsa Guo, Yike Bai, Wenjia Banerjee, Subhashis Pei, Linmin Murat, A.K. Rosas-González, Sarahi Zemmoura, Ilyess Tauber, Clovis Vu, Minh H. Nyholm, Tufve Löfstedt, Tommy Ballestar, Laura Mora Vilaplana, Veronica McHugh, Hugh Talou, Gonzalo Maso Wang, Alan Patel, Jay Chang, Ken Hoebel, Katharina Gidwani, Mishka Arun, Nishanth Gupta, Sharut Aggarwal, Mehak Singh, Praveer Gerstner, Elizabeth R. Kalpathy-Cramer, Jayashree Boutry, Nicolas Huard, Alexis Vidyaratne, Lasitha Rahman, Md Monibor Iftekharuddin, Khan M. Chazalon, Joseph Puybareau, Elodie Tochon, Guillaume Ma, Jun Cabezas, Mariano Llado, Xavier Oliver, Arnau Valencia, Liliana Valverde, Sergi Amian, Mehdi Soltaninejad, Mohammadreza Myronenko, Andriy Hatamizadeh, Ali Feng, Xue Dou, Quan Tustison, Nicholas Meyer, Craig Shah, Nisarg A. Talbar, Sanjay Weber, Marc-André Mahajan, Abhishek Jakab, Andras Wiest, Roland Fathallah-Shaykh, Hassan M. Nazeri, Arash Milchenko, Mikhail Marcus, Daniel Kotrotsou, Aikaterini Colen, Rivka Freymann, John Kirby, Justin Davatzikos, Christos Menze, Bjoern Bakas, Spyridon Gal, Yarin Arbel, Tal McGill University MontrealQC Canada Group University of Oxford Oxford United Kingdom University of Pennsylvania PhiladelphiaPA United States Department of Radiology Perelman School of Medicine The University of Pennsylvania PhiladelphiaPA United States Department of Pathology and Laboratory Medicine Perelman School of Medicine University of Pennsylvania PhiladelphiaPA United States University Institute of Diagnostic and Interventional Neuroradiology University of Bern Inselspital Bern University Hospital Bern Switzerland Department of Radiology University of Texas Southwestern Medical Center DallasTX United States Department of Bioengineering University of Texas DallasTX United States Advanced Imaging Research Center University of Texas Southwestern Medical Center DallasTX United States Universidad de los Andes Bogotá Colombia Data Science Institute Imperial College London London United Kingdom NIHR Imperial BRC ITMAT Data Science Group Imperial College London London United Kingdom Department of Brain Sciences Imperial College London London United Kingdom Machine Intelligence Unit Indian Statistical Institute Kolkata India Department of CSE University of Calcutta Kolkata India Department of Information Technology Uppsala University Uppsala Sweden Department of Diagnostic Radiology The University of Pittsburgh Medical Center PittsburghPA United States UMR U1253 iBrain Université de Tours Inserm Tours France Department of Radiation Sciences Umeå University Umeå Sweden Department of Computing Science Umeå University Umeå Sweden Signal Theory and Communications Department Universitat Politècnica de Catalunya Barcelona Tech Barcelona Spain Faculty of Medical and Health Sciences University of Auckland Auckland New Zealand Radiology Department Auckland City Hospital Auckland New Zealand Auckland Bioengineering Institute University of Auckland New Zealand Athinoula A. Martinos Center for Biomedical Imaging Department of Radiology

Deep learning (DL) models have provided state-of-the-art performance in various medical imaging benchmarking challenges, including the Brain Tumor Segmentation (BraTS) challenges. However, the task of focal pathology multi-compartment segmentation (e.g., tumor and lesion sub-regions) is particularly challenging, and potential errors hinder translating DL models into clinical workflows. Quantifying the reliability of DL model predictions in the form of uncertainties could enable clinical review of the most uncertain regions, thereby building trust and paving the way toward clinical translation. Several uncertainty estimation methods have recently been introduced for DL medical image segmentation tasks. Developing scores to evaluate and compare the performance of uncertainty measures will assist the end-user in making more informed decisions. In this study, we explore and evaluate a score developed during the BraTS 2019 and BraTS 2020 task on uncertainty quantification (QU-BraTS) and designed to assess and rank uncertainty estimates for brain tumor multi-compartment segmentation. This score (1) rewards uncertainty estimates that produce high confidence in correct assertions and those that assign low confidence levels at incorrect assertions, and (2) penalizes uncertainty measures that lead to a higher percentage of under-confident correct assertions. We further benchmark the segmentation uncertainties generated by 14 independent participating teams of QU-BraTS 2020, all of which also participated in the main BraTS segmentation task. Overall, our findings confirm the importance and complementary value that uncertainty estimates provide to segmentation algorithms, highlighting the need for uncertainty quantification in medical image analyses. Finally, in favor of transparency and reproducibility, our evaluation code is made publicly available at https://***/RagMeh11/QU-BraTS. © 2021, CC BY.

关键词： Benchmarking

Reduced thermal conductivity of epitaxial GaAs on Si due to symmetry-breaking biaxial strain

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arXiv 2019年

作者： Vega-Flick, Alejandro Jung, Daehwan Yue, Shengying Bowers, John E. Liao, Bolin Department of Mechanical Engineering University of California Santa BarbaraCA93106 United States Institute for Energy Efficiency University of California Santa BarbaraCA93106 United States Center for Opto-Electronics Materials and Devices Korea Institute of Science and Technology Seoul02792 Korea Republic of Materials Department University of California Santa BarbaraCA93106 United States Department of Electrical and Computer Engineering University of California Santa BarbaraCA93106 United States

Epitaxial growth of III-V semiconductors on Si is a promising route for silicon photonics. Threading dislocations and the residual thermal stress generated during growth are expected to affect the thermal conductivity of the III-V semiconductors, which is crucial for efficient heat dissipation from photonic devices built on this platform. In this work, we combine a non-contact laser-induced transient thermal grating technique with ab initio phonon simulations to investigate the in-plane thermal transport of epitaxial GaAs-based buffer layers on Si, employed in the fabrication of III-V quantum dot lasers. Surprisingly, we find a significant reduction of the in-plane thermal conductivity of GaAs, up to 19%, as a result of a small in-plane biaxial stress of ∼250 MPa. Using ab initio phonon calculations, we attribute this effect to the enhancement of phonon-phonon scattering caused by the in-plane biaxial stress, which breaks the cubic crystal symmetry of GaAs. Our results indicate the importance of eliminating the residual thermal stress in the epitaxial III-V layers on Si to avoid the reduction of thermal conductivity and facilitate heat dissipation. Additionally, our results showcase potential means of effectively controlling thermal conductivity of solids with external strain/stress. Copyright © 2019, The Authors. All rights reserved.

关键词： III-V semiconductors

A new battery management system for self-powered smart shoes

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AIP Conference Proceedings 2020年第1期2228卷

作者： Muladi Adim Firmansah Aripriharta Ilham Ari Elbaith Zaeni Anik Nur Handayani I. Made Wirawan Gwo Jiun Horng 1Department of Electrical Engineering Faculty of Engineering Universitas Negeri Malang Indonesia 2Centre of Advanced Materials for Renewable Energy Indonesia 3Graduate School Faculty of Engineering Universitas Negeri Malang Indonesia 4Department of Computer Science and Information Engineering Southern Taiwan University of Science and Technology Tainan City Taiwan

This paper presents a battery management system on a self-powered smart shoes application. As a mobile device, smart shoes have limited battery reserves and are separated from installed energy sources. The use of batteries must be as save as possible so that the device can still function while in use. Smart shoes can sense heart rate and oxygen levels in blood. Both collected data is encapsulated in a single frame prior to sending it to the database server through wireless sensor network. We developed an energy-saving method to extend battery life through duty cycle. The proposed method used sleep feature, data reduction, wireless transceiver optimization, and fixed network authentication configuration. The sleep feature allows the device active during data acquisition and delivery, the rest it will be going to sleep. The data is reduced to minimize power transmission. Testing energy consumption on devices with proposed battery management is carried out on wireless network ecosystem that uses static addressing. The results are compared with energy consumption from devices with conventional battery management. The results show that the proposed battery management system can reduce energy consumption up to 4.85%. Overall the proposed method has better performance than the conventional method.

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