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Design spectra including effect of rupture directivity in near-fault region

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Earthquake Engineering and Engineering Vibration 2006年第2期5卷 159-170页

作者：徐龙军 Adrian rodriguez-Marek 谢礼立 College of Engineering Ocean University of China Department of Civil and Environmental Engineering Washington State University Pullman WA 99164-2910 USA Professor School of Civil Engineering Harbin Institute of Technology

In order to propose a seismic design spectrum that includes the effect of rupture directivity in the near-fault region, this study investigates the application of equivalent pulses to the parameter attenuation relationships developed for near-fault, forward-directivity motions. Near-fault ground motions are represented by equivalent pulses with different waveforms defined by a small number of parameters （peak acceleration, A, and velocity V; and pulse period, Tv）. Dimensionless ratios between these parameters （e.g., ATv/V, VTv/D） and response spectral shapes and amplitudes are examined for different pulses to gain insight on their dependence on basic pulse waveforms. Ratios of ATv/V, VTv/D, and the ratio of pulse period to the period for peak spectral velocity （Tv-p） are utilized to quantify the difference between rock and soil sites for near-fault forward-directivity ground motions. The ATv/Vratio of recorded near-fault motions is substantially larger for rock sites than that for soil sites, while Tvp/Tv ratios are smaller at rock sites than at soil sites. Furthermore, using simple pulses and available predictive relationships for the pulse parameters, a preliminary model for the design acceleration response spectra for the near-fault region that includes the dependence on magnitude, rupture distance, and local site conditions are developed.

关键词： near-fault ground motion pulse attenuation relation velocity pulse period design spectrum

An execution control method for the Aerostack aerial robotics framework

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Frontiers of Information Technology & Electronic Engineering 2019年第1期20卷 60-75页

作者： Martin MOLINA Alberto CAMPORREDONDO Hriday BAVLE AlejANDro rodriguez-RAMOS Pascual CAMPOY Department of Artificial Intelligence Universidad Politécnica de Madrid Centre for Automation and Robotics Universidad Politécnica de Madrid

Execution control is a critical task of robot architectures which has a deep impact on the quality of the final system. In this study, we describe a general method for execution control, which is a part of the Aerostack software framework for aerial robotics, and present technical challenges for execution control and design decisions to develop the method. The proposed method has an original design combining a distributed approach for execution control of behaviors(such as situation checking and performance monitoring) and centralizes coordination to ensure consistency of the concurrent execution. We conduct experiments to evaluate the method. The experimental results show that the method is general and usable with acceptable development efforts to efficiently work on different types of aerial missions. The method is supported by standards based on a robot operating system(ROS) contributing to its general use, and an open-source project is integrated in the Aerostack framework. Therefore, its technical details are fully accessible to developers and freely available to be used in the development of new aerial robotic systems.

关键词： Aerial robotics Control architecture Behavior-based control Executive system

Concentrations of disinfection by-products in swimming pool following modifications of the water treatment process:An exploratory study

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Journal of Environmental Sciences 2017年第8期29卷 163-172页

作者： Robert Tardif Manuel rodriguez Cyril Catto Ginette Charest-Tardif Sabrina Simard Department of Environmental and Occupational Health School of Public HealthUniversité de Montréal NSERC Industrial Research Chair on Drinking Water Université Laval

The formation and concentration of disinfection by-products（DBPs） in pool water and the ambient air vary according to the type of water treatment process used. This exploratory study was aimed at investigating the short-term impact of modifications of the water treatment process on traditional DBP levels（e.g., trihalomethanes（THMs）, chloramines） and emerging DBPs（e.g., Halonitromethanes, Haloketones, NDMA） in swimming pool water and/or air. A sampling program was carried to understand the impact of the following changes made successively to the standard water treatment process： activation of ultraviolet（UV）photoreactor, halt of air stripping with continuation of air extraction from the buffer tank,halt of air stripping and suppression of air extraction from the buffer tank, suppression of the polyaluminium silicate sulfate（PASS） coagulant. UV caused a high increase of Halonitromethanes（8.4 fold）, Haloketones（2.1 fold）, and THMs in the water（1.7 fold） and, of THMs in the air（1.6 fold） and contributed to reducing the level of chloramines in the air（1.6fold） and NDMA in the water（2.1 fold）. The results highlight the positive impact of air stripping in reducing volatile contaminants. The PASS did not change the presence of DBPs, except for the THMs, which decrease slightly with the use of this coagulant. This study shows that modifications affecting the water treatment process can rapidly produce important and variable impacts on DBP levels in water and air and suggests that implementation of any water treatment process to reduce DBP levels should take into account the specific context of each swimming pool.

关键词： Disinfection by-products Swimming pool UV rays Air stripping Chloramines Emerging DBPs NDMA

Representation of near-fault pulse-type ground motions

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Earthquake Engineering and Engineering Vibration 2005年第2期4卷 191-199页

作者：谢礼立徐龙军 Adrian rodriguez-Marek School of Civil Engineering Harbin Institute of TechnologyHarbin 150090China Institute of Engineering MechanicsChina Earthquake AdministrationHarbin 150080China Professor School of Civil Engineering Harbin Institute of TechnologyHarbin 150090China Ph.D.student Department of Civil and Environmental Engineering Washington State UniversityPullmanWA 99164-2910USA AssistantProfessor

Near-fault ground motions with long-period pulses have been identified as critical in the design of structures. To aid in the representation of this special type of motion, eight simple pulses that characterize the effects of either the flingstep or forward-directivity are considered. Relationships between pulse amplitudes and velocity pulse period for different pulses are discussed. Representative ratios and peak acceleration amplification can exhibit distinctive features depending on variations in pulse duration, amplitude and the selected acceleration pulse shape. Additionally, response spectral characteristics for the equivalent pulses are identified and compared in terms of fixed PGA and PGV, respectively. Response spectra are strongly affected by the duration of pulses and the shape of the basic pulses. Finally, dynamic time history response features of a damped SDOF system subjected to pulse excitations are examined. These special aspects of pulse waveforms and their response spectra should be taken into account in the estimation of ground motions for a project site close to a fault.

关键词： near-fault ground motion pulse velocity pulse period response spectrum

Predefined-Time Backstepping Stabilization of Autonomous Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2022年第11期9卷 2020-2022页

作者： Alison Garza-Alonso Michael Basin Pablo Cesar rodriguez-Ramirez the School of Physical and Mathematical Sciences Autonomous University of Nuevo LeonSan Nicolas de los GarzaNuevo Leon 66455Mexico Ningbo Institute of Intelligent Equipment Technology Zhejiang 315032China

Dear Editor,In this letter,the backstepping technique is applied to solve the predefined-time stabilization problem for autonomous nonlinear systems,where nonlinear terms are unknown but satisfy a linear growth condition.A linear time-varying control law is designed to drive all states of an autonomous nonlinear system to the origin for an a priori preassigned time.

关键词： nonlinear autonomous satisfy

Yet Another Intelligent Code-Generating System： A Flexible and Low-Cost Solution

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Journal of Computer Science & Technology 2018年第5期33卷 940-965页

作者： Joao Fabricio Filho Luis Gustavo Araujo rodriguez Anderson Faustino da Silva Department of Informatics State University of Maringd Maringd-PR 87020-900 Brazil Federal University of Technology -- Parand Campo Mourao-PR 87301-899 Brazil

Modern compilers apply various code transformation algorithms to improve the quality of the target code. However, a complex problem is to determine which transformation algorithms must be utilized. This is difficult because of three reasons： a number of transformation algorithms, various combination possibilities, and several configuration possibil- ities. Over the last few years, various intelligent systems were presented in the literature. The goal of these systems is to search for transformation algorithms and thus apply them to a certain program. This paper proposes a flexible, low-cost and intelligent system capable of identifying transformation algorithms for an input program, considering the program＇s specific features. This system is flexible for parameterization selection and has a low-computational cost. In addition, it has the capability to maximize the exploration of available computational resources. The system was implemented under the Low Level Virtual Machine infrastructure and the results indicate that it is capable of exceeding, up to 21.36%, performance reached by other systems. In addition, it achieved an average improvement of up to 17.72% over the most aggressive compiler optimization level of the Low Level Virtual Machine infrastructure.

关键词： compiler code transformation iterative compilation knowledge representation machine learning

Traditional Chinese Medicine in Canada: An Indigenous Perspective

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Chinese Medicine and Culture 2019年第1期2卷 1-5页

作者： Honoré France Carmen rodriguez Department of Educational Psychology and Leadership Studies Faculty of EducationUniversity of VictoriaVictoriaCanada

This paper summarizes the practice of traditional Chinese medicine(TCM)in Canada by exploring why so many indigenous people are drawn to *** present a brief history of TCM in Canada,including its acceptance by 5 of the 10 provinces in Canada as one of the medical approaches,accepted and regulated by the *** philosophy embedded in TCM is compared to indigenous philosophy,and there is a description of some of the plants and animals used as remedies in indigenous folk *** addition,there is a short description of how TCM psychology parallels some practices in indigenous psychology.

关键词： Canada indigenous philosophy traditional Chinese medicine

Structure of Ligand-Bound Intermediates of Crop ABA Receptors Highlights PP2C as Necessary ABA Co-receptor

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Molecular Plant 2017年第9期10卷 1250-1253页

作者： María Moreno-Alvero Cristina Yunta miguel Gonzalez-Guzman Jorge Lozano-Juste Juan Luis Benavente Vicent Arbona Margarita Menéndez Martin Martinez-Ripoll Lourdes Infantes Aurelio Gomez-Cadenas Pedro L. rodriguez Armando Albert Biotecnologia Departament Ciències Agràries i del Medi Natural Universitat Jaume I 12071 Castelló de la Plana Spain [∗]Corresponding author [∗∗]Corresponding authorThese authors contributed equally to this article.

Dear Editor Abscisic acid （ABA） is the main phytohormone involved in adaptive crop responses to drought. ABA signaling relies on the family of pyrabactin resistance 1/PYRl-like/regulatory components of ABA receptors （PYR/PYL/RCAR）, which upon ABA binding form high-affinity ternary complexes with clade A protein phosphatases type 2C （PP2Cs） and inhibit them （Cutler et al., 2010）. This results in the activation of an SnRK2-dependent phosphorylation cascade affecting a high number of targets in the plant cells, regulating stomatal aper- ture and the expression of stress-responsive genes （Cutler et al., 2010）.

关键词： Structure of Ligand-Bound Intermediates Crop ABA Receptors Highlights PP2C

Improving surface integrity when drilling CFRPs and Ti-6Al-4V using sustainable lubricated liquid carbon dioxide

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Chinese Journal of Aeronautics 2023年第7期36卷 129-146页

作者： In˜igo rodriguez Pedro Jose´ARRAZOLA Mikel CUESTA Luka STERLE Franci PUSˇAVEC Faculty of Engineering Mondragon UnibertsitateaArrasate-Mondragon 20500Spain Faculty of Mechanical Engineering University of LjubljanaLjubljana 1000Slovenia

In the quest for decreasing fuel consumption and resulting gas emissions in the aeronautic sector,lightweight materials such as Carbon Fiber Reinforced Polymers(CFRPs)and Ti-6Al-4V alloys are being *** materials,with excellent weight-to-strength ratios,are widely used for structural applications in aircraft *** date,several studies have been published showing that the use of metalworking fluids(MWFs),special tool geometries,or advanced machining techniques is required to ensure a surface quality that meets aerospace component *** MWFs pose a number of environmental and worker health hazards and also degrade the mechanical properties of CFRPs due to water absorption in the ***,a transition to more environmentally friendly cooling/lubrication techniques that prevent moisture problems in the composite is *** research shows that lubricated LCO_(2) is a viable option to improve the quality of drilled CFRP and titanium aerospace components compared to dry machining,while maintaining clean work *** results show that the best combination of tool geometry and cooling conditions for machining both materials is drilling with Brad point drills and lubricated LCO_(2).Drilling under these conditions resulted in a 90%improvement in fiber pullout volume compared to dry machined CFRP *** addition,a 33% reduction in burr height and a 15% improvement in surface roughness were observed compared to dry drilling of titanium.

关键词： Carbon fibers Cryogenics Green manufacturing Machining Solid lubricants Surface morphology Titanium alloys