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Model-based framework for multi-axial real-time hybrid simulation testing

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Earthquake Engineering and Engineering Vibration 2017年第4期16卷 671-691页

作者： Gaston A.Fermandois Billie F.Spencer,jr. Department of Civil and Environmental Engineering University of Illinois at Urbana-ChampaignUrbanaIL 61801USA

Real-time hybrid simulation is an efficient and cost-effective dynamic testing technique for performance evaluation of structural systems subjected to earthquake loading with rate-dependent behavior. A loading assembly with multiple actuators is required to impose realistic boundary conditions on physical specimens. However, such a testing system is expected to exhibit significant dynamic coupling of the actuators and suffer from time lags that are associated with the dynamics of the servo-hydraulic system, as well as control-structure interaction （CSI）. One approach to reducing experimental errors considers a multi-input, multi-output （MIMO） controller design, yielding accurate reference tracking and noise rejection. In this paper, a framework for multi-axial real-time hybrid simulation （maRTHS） testing is presented. The methodology employs a real-time feedback-feedforward controller for multiple actuators commanded in Cartesian coordinates. Kinematic transformations between actuator space and Cartesian space are derived for all six-degrees-of- freedom of the moving platform. Then, a frequency domain identification technique is used to develop an accurate MIMO transfer function of the system. Further, a Cartesian-domain model-based feedforward-feedback controller is implemented for time lag compensation and to increase the robustness of the reference tracking for given model uncertainty. The framework is implemented using the 1/5th-scale Load and Boundary Condition Box （LBCB） located at the University of Illinois at Urbana- Champaign. To demonstrate the efficacy of the proposed methodology, a single-story frame subjected to earthquake loading is tested. One of the columns in the fraane is represented physically in the laboratory as a cantilevered steel column. For real- time execution, the numerical substructure, kinematic transformations, and controllers are implemented on a digital signal processor. Results show excellent performance of the maRTHS framework when

关键词： real-time hybrid simulation multiple actuators dynamic coupling kinematic transformations model-basedcompensation

Organizational Behavior Don Hellriegel, John W. Slocum, jr.

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2007年

作者： Don Hellriegel John W. Slocum jr.

来源：畅想之星图书光盘版（南... 评论

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Magnetic Cooling

Journal of Rare Earths 2005年第4期23卷 I0001-I0002页

作者： Karl A. Gschneidner jr. Materials and Engineering Physics Ames Laboratory Department of Materials Science and Engineering Iowa State University Ames IA 50011-3020 USAMaterials and Engineering Physics Ames Laboratory Department of Materials Science and Engineering Iowa State University Ames IA 50011-3020 USA

The world has become highly dependent on reliable refrigeration technology. Without it, our food supply would be still seasonal and limited to locally produced nonperishable items; comfortable living conditions via climate control would be impossible; and certain medical advancements, e.g. MRI diagnostics, organ transplantation, organ and tissue cryo-storage, and cryo-surgery would be impossible. This technology remains essentially unchanged since it was invented 100 years ago.

关键词： Magnetic Cooling

Effect of rGO support on Gd@ZnO for UV-visible-light driven photocatalytic organic pollutant degradation

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Journal of Rare Earths 2023年第10期41卷 1525-1531,I0002页

作者： Baskaran Palanivel Md Shahadat Hossain Romulo R.Macadangdang jr. S.Sahaya Jude Dhas Abdullah M.Al-Enizi Mohd Ubaidullah Woo Kyoung Kim Sreedevi Gedi S.Ignatius Arockiam Department of Physics Kings Engineering CollegeSriperumbudurKancheepuram602117Tamil NaduIndia Department of Innovation Systems Engineering Graduate School of EngineeringUtsunomiya UniversityYoto 7-1-2Utsunomiya 321-8585Japan College of Allied Health National UniversityManila1008Philippines Department of Chemistry College of ScienceKing Saud UniversityRiyadh11451Saudi Arabia School of Chemical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea PG and Research Department of Chemistry GTN Arts CollegeDindigul624005Tamil NaduIndia

In this manuscript,we report the hydrothermally prepared rGO/Gd@ZnO nanocomposite for the utilization of photocatalytic Rh B(rhodamine B)dye *** required characterization techniques were carried out to analyse the structural,morphological,chemical,environmental and optical behaviour of the prepared *** efficiency of the prepared nanoparticles was studied by Rh B dye degradation upon UV-Vis-light illumination which reveals that composite catalyst degrades the dye molecule about 91%after 40 min of *** comparing the higher degradation efficiency of the rGO/Gd@ZnO nanocomposite with that of ZnO and Gd doped ZnO,it reveals a greater reduction of charge carriers'recombination,higher visible-light utilization and higher adsorption *** trapping experiment and recycling test were conducted to study the influence of active radicals for the degradation reaction and to know the stability of the prepared nanocomposite,***,this rGO supported Gd doped ZnO nanocomposite can provide a new path way in preparing a highly efficient photocatalyst for organic pollutant degradation at large.

关键词： rGO Gd doped ZnO UV-Vis photocatalyst Dye degradation Rare earths

Optimal escape theory predicts escape behaviors beyond flight initiation distance:risk assessment and escape by striped plateau lizards Sceloporus virgatus

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Current Zoology 2009年第2期55卷 123-131页

作者： William E. COOPER jr. Department of Biology Indiana University Purdue University Fort Wayne

Escape theory predicts that flight initiation distance (FID=distance between predator and prey when escape begins) is longer when risk is greater and shorter when escape is more costly. A few tests suggest that escape theory applies to distance fled. Escape models have not addressed stochastic variables,such as probability of fleeing and of entering refuge,but their economic logic might be applicable. Experiments on several risk factors in the lizard Sceloporus virgatus confirmed all predictions for the above escape variables. FID was greater when approach was faster and more direct,for lizards on ground than on trees,for lizards rarely exposed to humans,for the second of two approaches,and when the predator turned toward lizards rather than away. Lizards fled further during rapid and second consecutive approaches. They were more likely to flee when approached directly,when a predator turned toward them,and during second approaches. They were more likely to enter refuge when approached rapidly. A novel finding is that perch height in trees was unrelated to FID because lizards escaped by moving out of sight,then moving up or down unpredictably. These findings add to a growing body of evidence supporting predictions of escape theory for FID and distance fled. They show that two probabilistic aspects of escape are predictable based on relative predation risk levels. Because individuals differ in boldness,the assessed optimal FID and threshold risks for fleeing and entering refuge are exceeded for an increasing proportion of individuals as risk

关键词：动物学蜥蜴食肉动物研究

脑瘫髋关节的定期监控和及时手术预防疼痛性髋脱位

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中华骨科杂志 2023年第9期43卷 605-612页

作者：刘海清 David P.Roye jr. 李旭汕头大学广州华新骨科医院广州510630

脑瘫是最常见的发病于儿童期而机体功能受损影响终身的神经肌肉系统疾患,新生儿发病率约为1/500,目前全世界约有1700万脑瘫患者。脑瘫并不特指某个具体疾病,而是指发育中的胎儿或婴幼儿遭受非进展性脑损伤引发运动发育和姿势控制的永久... 详细信息

脑瘫是最常见的发病于儿童期而机体功能受损影响终身的神经肌肉系统疾患,新生儿发病率约为1/500,目前全世界约有1700万脑瘫患者。脑瘫并不特指某个具体疾病,而是指发育中的胎儿或婴幼儿遭受非进展性脑损伤引发运动发育和姿势控制的永久性异常而导致机体活动受限的一组临床症候群。脑瘫可引发诸多肢体畸形,其中髋关节移位是常见的畸形之一,发生比例仅次于马蹄足。本文回顾文献并总结归纳脑瘫髋关节移位的病理生理机制、临床症状、与大运动功能分级的关系及骨科相关治疗。脑瘫髋关节移位主要是由于早期缺乏正常应力刺激及髋关节周围持续的不对称性肌力牵拉所致。髋关节移位早期常无症状,但若不及时治疗会逐渐出现髋关节半脱位或脱位,导致髋关节疼痛和活动受限,从而影响患者活动能力和增加日常护理难度。脑瘫髋移位与大运动功能分级密切相关,大运动分级越高髋移位风险越大,而通过髋关节监控可明显减少髋关节脱位的发生率。因此,建立规范的脑瘫髋关节监控流程、及时干预、防止髋脱位和疼痛的出现是国内外学者的共识。目前脑瘫髋关节移位的手术治疗主要分为三类:预防性手术、重建性手术和姑息性手术。

关键词：脑性瘫痪髋关节关节脱位早期医疗干预

Selling : building partnerships Barton A. Weitz, Stephen B. Castleberry, John F. Tanner, jr. 5th ed.

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Improving Energy and Power Efficiency Using NComputing and Approaches for Predicting Reliability of Complex Computing Systems

丛书名： The Irwin/McGraw-Hill series in marketing

2004年

作者： Barton A. Weitz Stephen B. Castleberry John F. Tanner jr.

来源：畅想之星图书光盘版（南... 评论

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International Journal of Automation and computing 2010年第2期7卷 153-159页

作者： Hoang Pham Hoang Pham jr. Department of Industrial and Systems Engineering Rutgers University Timothy Christian School

Opting to follow the computing-design philosophy that the best way to reduce power consumption and increase energy efficiency is to reduce waste, we propose an architecture with a very simple ready-implementation by using an NComputing device that can allow multi-users but only one computer is needed. This intuitively can save energy, space as well as cost. In this paper, we propose a simple and realistic NComputing architecture to study the energy and power-efficient consumption of desktop computer systems by using the NComputing device. We also propose new approaches to estimate the reliability of k-out-of-n systems based on the delta method. The k-out-of-n system consisting of n subsystems works if and only if at least k-of-the-n subsystems work. More specificly, we develop approaches to obtain the reliability estimation for the k-out-of-n systems which is composed of n independent and identically distributed subsystems where each subsystem （or energy-efficient usage application） can be assumed to follow a two-parameter exponential lifetime distribution function. The detailed derivations of reliability estimation of k-out-of-n systems based on the biased-corrected estimator, known as delta method, the uniformly minimum variance unbiased estimate （UMVUE） and maximum likelihood estimate （MLE） are discussed. An energy-management NComputing application is discussed to illustrate the reliability results in terms of the energy consumption usages of a computer system with qua（t-core, 8 GB of RAM, and a GeForce 9800GX-2 graphics card to perform various complex applications. The estimated reliability values of systems based on the UMVUE and the delta method differ only slightly. Often the UMVUE of reliability for a complex system is a lot more difficult to obtain, if not impossible. The delta method seems to be a simple and better approach to obtain the reliability estimation of complex systems. The results of this study also show that, in practice, the NComputing archite

关键词： Energy efficiency Ncomputing k-out-of-n system exponential distribution reliability estimation uniformly minimum variance unbiased estimate (UMVUE) maximum likelihood estimate (MLE).

Very weak solutions to the two-dimensional Monge-Ampére equation Dedicated to Professor Jean-Yves Chemin on the Occasion of His 60th Birthday

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Science China Mathematics 2019年第6期62卷 1041-1056页

作者： Wentao Cao László Székelyhidi jr. Institut für Mathematik Universit?t Leipzig

In this short note we revisit the convex integration approach to constructing very weak solutions to the 2D Monge-Ampére equation with H?lder-continuous ?rst derivatives of exponent β < 1/5. Our approach is based on combining the approach of Lewicka and Pakzad(2017) with a new diagonalization procedure which avoids the use of conformal coordinates, which was introduced by De Lellis et al.(2018) for the isometric immersion problem.

关键词： Monge-Ampére equation convex integration weak solutions