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ODS & Modal Testing Using a Transmissibility Chain

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Sound & Vibration 2018年第2期52卷 2-7页

作者： Brian Schwarz Patrick McHargue mark richardson Vibrant Technology Inc. Centennial CO United States

In this paper, we show how Operating Deflection Shapes (ODS’s) andmode shapes can be obtained experimentally from measurements thatare made using only two sensors and two short wires to connect them to amulti-channel acquisition system. This new test procedure is depicted inFigure 1. Not only is the equipment required to do a test much more costeffective, but this method can be used to test any sized test article, especiallylarge ones.

关键词： Fourier spectrum (DFT) Auto power spectrum (APS) Crosspower spectrum (XPS) Frequency Response Function (FRF) OperatingDeflection Shape (ODS) Experimental Mode Shape (EMA Mode) OperationalMode Shape (OMA Mode) Modal Assurance Criterion (MAC) ShapeDifference Indicator (SDI)

Misdiagnosis of Earth climate sensitivity based on energy balance model results

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Science Bulletin 2015年第15期60卷 1370-1377页

作者： mark richardson Zeke Hausfather Dana A.Nuccitelli Ken Rice John P.Abraham Department of Meteorology University of Reading Climate Physics Section Jet Propulsion Laboratory California Institute of Technology Energy and Resources Group University of CaliforniaBerkeley Skeptical Science Brisbane Institute for Astronomy Royal Observatory University of Edinburgh School of Engineering University of St. Thomas St. Paul

Monckton of Brenchley et al.(Sci Bull60:122–135, 2015)(hereafter called M15) use a simple energy balance model to estimate climate response. They select parameters for this model based on semantic arguments, leading to different results from those obtained in physics-based studies. M15 did not validate their model against observations, but instead created synthetic test data based on subjective assumptions. We show that M15 systematically underestimate warming: since 1990, most years were warmer than their modelled upper limit. During 2000–2010, RMS error and bias are approximately 150 % and 350 % larger than for the CMIP5 median, using either the Berkeley Earth or Cowtan and Way surface temperature data. We show that this poor performance can be explained by a logical flaw in theparameter selection and that selected parameters contradict observational estimates. M15 also conclude that climate has a near-instantaneous response to forcing, implying no net energy imbalance for the Earth. This contributes to their low estimates of future warming and is falsified by Argo float measurements that show continued ocean heating and therefore a sustained energy imbalance. M15's estimates of climate response and future global warming are not consistent with measurements and so cannot be considered credible.

关键词：能量平衡模型气候敏感性地球误诊气候响应观测方法全球变暖均方根误差

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火星大气边界层沙尘传输的模拟研究

火星大气边界层沙尘传输的模拟研究

ROOT EXUDATES FROM CANOLA EXHIBIT BIOLOGICAL NITRIFICATION INHIBITION AND ARE EFFECTIVE IN INHIBITING AMMONIA OXIDATION IN SOIL

2018年中国地球科学联合学术年会

作者：吴兆朋 mark I.richardson 张曦 Claire E.Newman 李陶中山大学中国科学技术大学 Aeolis Research Pasadena University of California Santa Cruz

火星一直以来都是行星科学研究的热点,首要的研究目的自然是探索宇宙中的生命,而对于火星大气及气候的研究也随着火星探测器的增加而越来越多,对于两者的比较研究能帮助我们更好的了解地球大气的历史和未来。我们采用火星版本的天气研... 详细信息

火星一直以来都是行星科学研究的热点,首要的研究目的自然是探索宇宙中的生命,而对于火星大气及气候的研究也随着火星探测器的增加而越来越多,对于两者的比较研究能帮助我们更好的了解地球大气的历史和未来。我们采用火星版本的天气研究和预测模型(MarsWRF)对火星对流边界层(CBL)的气象过程和沙尘传输进行了大涡旋模拟(LES)。研究表明沙尘对阳光的遮挡产生的阴影效应会减弱边界层的对流强度,但沙尘的不均匀分布会增强地表和大气中的热对比度,进而通过增加浮力项而增强边界层的对流。如果扬沙速度足够快,由于沙尘不均匀分布而增加的对流能量可能会超过阴影效应减少的能量,从而导致边界层高度的抬升,我们发现火星一天中沙尘的最大不均匀度与边界层的最大高度存在正比关系,这为研究火星以及地球沙漠地区的边界层高度提供了新的认识。

关键词： CBL 光学厚度大气边界层

来源： cnki会议评论

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Frontiers of Agricultural Science and Engineering 2022年第2期9卷 177-186页

作者： Cathryn A.O'SULLIVAN Elliott G.DUNCAN Margaret M.ROPER Alan E.richardson John A.KIRKEGAARD mark B.PEOPLES CSIRO Agriculture&Food 306 Carmody RdSt LuciaQld 4067Australia CSIRO Agriculture&Food Private Bag 5WembleyWA 6913Australia MBS Environmental 4 Cook StreetWest PerthWA 6005Australia CSIRO Agriculture&Food GPO Box 1700CanberraACT 2601Australia

A range of plant species produce root exudates that inhibit ammonia-oxidizing *** biological nitrification inhibition(BNI)capacity can decrease N loss and increase N uptake from the *** study sought evidence for the existence and magnitude of BNI capacity in canola(Brassica napus).Seedlings of three canola cultivars,Brachiaria humidicola(BNI positive)and wheat(Triticum aestivum)were grown in a hydroponic *** exudates were collected and their inhibition of the ammonia oxidizing bacterium,Nitrosospira multiformis,was *** pot experiments were used to test the inhibition of native nitrifying communities in *** exudates from canola significantly reduced nitrification rates of both *** cultures and native soil microbial *** level of nitrification inhibition across the three cultivars was similar to the well-studied high-BNI species *** capacity of canola may have implications for the N dynamics in farming systems and the N uptake efficiency of crops in rotational farming *** reducing nitrification rates canola crops may decrease N losses,increase plant N uptake and encourage microbial N immobilization and subsequently increase the pool of organic N that is available for mineralization during the following cereal crops.

关键词： ammonia oxidizing microorganisms biological nitrification inhibition farming rotations nitrogen cycling nitrogen use efficiency

Iterative photonic processor for fast complexvalued matrix inversion

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Photonics Research 2022年第11期10卷 2488-2501页

作者： MINJIA CHEN QIXIANG CHENG MASAFUMI AYATA mark HOLM RICHARD PENTY Department of Engineering Centre for Photonic SystemsElectrical Engineering DivisionUniversity of CambridgeCambridge CB30FAUK Huawei Technologies(Sweden)AB 16440 KistaSweden

An N×N iterative photonic processor is proposed for the first time, we believe, for fast computation of complexvalued matrix inversion, a fundamental but computationally expensive linear algebra operation. Compared to traditional digital electronic processing, optical signal processing has a few unparalleled features that could enable higher representational efficiency and faster computing speed. The proposed processor is based on photonic integration platforms–the inclusion of Ⅲ-V gain blocks offers net neutral loss in the phase-sensitive loops. This is essential for the richardson iteration method that is adopted in this paper for complex linear systems. Wavelength multiplexing can be used to significantly improve the processing efficiency, allowing the computation of multiple columns of the inverse matrix using a single processor core. Performances of the key building blocks are modeled and simulated, followed by a system-level analysis, which serves as a guideline for designing an N×N richardson iteration processor. An inversion accuracy of>98%can be predicted for a 64×64 photonic processor with a>80times faster inversion rate than electronic processors. Including the power consumed by both active components and electronic circuits, the power efficiency of the proposed processor is estimated to be over an order of magnitude more energy-efficient than electronic processors. The proposed iterative photonic integrated processor provides a promising solution for future optical signal processing systems.

关键词： valued matrix iteration

An implantable,wireless,battery-free system for tactile pressure sensing

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Microsystems & Nanoengineering 2023年第5期9卷 309-320页

作者： Lin Du Han Hao Yixiao Ding Andrew Gabros Thomas C.E.Mier Jan Van der Spiegel Timothy H.Lucas Firooz Aflatouni Andrew G.richardson mark G.Allen Department of Electrical and Systems Engineering School of Engineering and Applied ScienceUniversity of PennsylvaniaPhiladelphiaPAUSA Department of Neurosurgery Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPAUSA Departments of Neurosurgery and Biomedical Engineering Ohio State UniversityColumbusOHUSA

The sense of touch is critical to dexterous use of the hands and thus an essential component of efforts to restore hand function after amputation or *** systems have addressed this goal with wearable tactile ***,such wearable sensors are suboptimal for neuroprosthetic systems designed to reanimate a patient’s own paralyzed ***,we developed an implantable tactile sensing system intended for subdermal *** system is composed of a microfabricated capacitive pressure sensor,a custom integrated circuit supporting wireless powering and data transmission,and a laser-fused hermetic silica *** miniature device was validated through simulations,benchtop assessment,and testing in a primate *** sensor implanted in the fingertip accurately measured applied skin forces with a resolution of 4.3 *** output from this novel sensor could be encoded in the brain with microstimulation to provide tactile *** broadly,the materials,system design,and fabrication approach establish new foundational capabilities for various applications of implantable sensing systems.

关键词： system battery fused

Cooperative visibility maintenance in SE（3） for multi-robot-networks with limited field-of-view sensors

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Control Theory and Technology 2017年第4期15卷 246-257页

作者： Hasan A. Poonawala mark W. Spong Institute for Computational Engineering & Sciences University of Texas Austin U.S.A. Erik Jonsson School of Engineering & Computer Science University of Texas at Dallas Richardson U.S.A.

Coordination of motion between multiple robots requires the robots to sense their relative poses. Common sensors depend on maintaining a line-of-sight between the sensor and the object being sensed. When the robots move relative to one another, they must coordinate their motions to ensure that these lines-of-sight are preserved. We propose a control method to preserve desired lines-of-sight in a multi-robot system where each robot has configuration space SE（3）. A key feature of the control method is its ability to reject persistent bounded disturbances, enabling its use alongside additional control tasks. We demonstrate the effectiveness of the edge-preserving control in simulations involving additional input velocities that tend to break the edges.

关键词： Multi-robot coordination decentralized control graph theoretic control

Exogenous cytokinin application to Actinidia chinensis var. deliciosa ‘Hayward’ fruit promotes fruit expansion through water uptake

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Horticulture Research 2017年第1期4卷 131-141页

作者： Simona Nardozza Helen L Boldingh mark W Wohlers Andrew P Gleave Zhiwei Luo Guglielmo Costa Elspeth A MacRae Michael J Clearwater Annette C richardson The New Zealand Institute for Plant&Food Research Limited(PFR) Mt Albert Research CentrePrivate Bag 92169AucklandNew Zealand PFR Ruakura Research CentrePrivate Bag 3123HamiltonNew Zealand Dipartimento di Scienzie Agrarie Universitàdi BolognaVia Fanin 46Bologna40127Italy PFR Te Puke Research CentreTe Puke3182New Zealand PFR Kerikeri Research CentrePrivate Bag 23KerikeriNew Zealand Scion Te Papa Tipu Innovation ParkPrivate Bag 3020RotoruaNew Zealand University of Waikato School of SciencePrivate Bag 3105HamiltonNew Zealand

Exogenous application of a cytokinin-like compound forchlorfenuron(CPPU)can promote fruit growth,although often at the expense of dry matter(DM),an important indicator of fruit *** chinensis ***‘Hayward’fruit are very responsive to CPPU treatments,but the mechanism underlying the significant fruit weight increase and associated decrease in DM is *** this study,we hypothesised that CPPU-enhanced growth increases fruit carbohydrate demand,but limited carbohydrate supply resulted in decreased fruit *** fruit development,CPPU effects on physical parameters,metabolites,osmotic pressure and transcriptional changes were assessed under conditions of both standard and a high carbohydrate *** showed that CPPU increased fruit fresh weight but the dramatic DM decrease was not carbohydrate *** glucose and fructose concentrations contributed to an increase in soluble carbohydrate osmotic pressure,which was correlated with increased water accumulation in CPPU-treated fruit and up-regulation of water channel aquaporin gene PIP2.4 at 49 days after *** analysis suggested that the molecular mechanism contributing to increased glucose and fructose concentrations was altered by carbohydrate *** standard carbohydrate supply,the early glucose increase in CPPU fruit was associated with reduced starch synthesis and increased starch *** carbohydrate supply was high,the early glucose increase in CPPU fruit was associated with a general decrease in starch synthesis but up-regulation of vacuolar invertase and fructokinase *** conclude that CPPU affected fruit expansion by increasing the osmotically-driven water uptake and its effect was not carbohydrate supply-limited.

关键词： CPPU Actinidia expansion

人HCN4通道的滞后现象:影响窦房结起搏的潜在决定因素(英文)

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生理学报 2010年第1期62卷 1-13页

作者：萧永福 Natalie Chandler Halina Dobrzynski Eric S.richardson Erica M.TenBroek Joshua J.Wilhelm Vinod Sharma Anthony Varghese mark R.Boyett Paul A.Iaizzo Daniel C.Sigg 美敦力公司心脏节律疾病管理部曼彻斯特大学医学院明尼苏达州大学外科学系明尼苏达州大学整合生物学与生理学系美敦力公司科学技术部威斯康辛大学雷河分校计算机系

超极化活化环核苷酸门控(hyperpolarization-activated cyclic-nucleotide-gated,HCN)通道参与调制心脏跳动的节律和速率。与HCN1和HCN2有所不同,慢通道HCN4可能不存在电压依赖的滞后现象。本研究采用单细胞膜片钳方法,在稳定转染hHCN4... 详细信息

超极化活化环核苷酸门控(hyperpolarization-activated cyclic-nucleotide-gated,HCN)通道参与调制心脏跳动的节律和速率。与HCN1和HCN2有所不同,慢通道HCN4可能不存在电压依赖的滞后现象。本研究采用单细胞膜片钳方法,在稳定转染hHCN4的HEK293细胞上进行电生理记录,观察hHCN4通道是否存在滞后现象,以及cAMP对其的调制作用;同时采用实时定量RT-PCR方法检测窦房结和心房组织中HCNs的表达。电压钳实验结果显示hHCN4电流(Ih)激活随着保持电位超极化的变化而向去极化方向移动。三角电位变化钳(triangular ramp)和动作电位钳的结果也显示了hHCN4的滞后现象。cAMP增加Ih电流幅度,且使电流激活向去极化方向移动,从而改变内源性hHCN4滞后行为。RT-PCR结果显示,人窦房结组织主要表达HCN4,占75%,HCN1占21%,HCN2占3%,HCN3占0.7%。以上结果提示,人窦房结组织主要表达HCN4亚型,hHCN4的Ih存在电压依赖性的滞后现象,且受cAMP调制。由此推断,hHCN4通道的滞后现象可能在窦房结起搏活动中起到了关键作用。

关键词： HCN4通道滞后窦房结 cAMP