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Continuous Action Reinforcement Learning for Control-Affine Systems with Unknown Dynamics

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IEEE/CAA Journal of Automatica Sinica 2014年第3期1卷 323-336页

作者： Aleksandra Faust Peter Ruymgaart Molly Salman Rafael Fierro Lydia tapia the Department of Computer Science University of New Mexico the Computer Science Department Austin College the Department of Electrical and Computer Engineering University of New Mexico

Control of nonlinear systems is challenging in *** making,performed many times per second,must ensure system *** input to perform a task often involves solving a nonlinear system of differential equations,which is a computationally intensive,if not intractable *** article proposes sampling-based task learning for controlaffine nonlinear systems through the combined learning of both state and action-value functions in a model-free approximate value iteration setting with continuous inputs.A quadratic negative definite state-value function implies the existence of a unique maximum of the action-value function at any *** allows the replacement of the standard greedy policy with a computationally efficient policy approximation that guarantees progression to a goal state without knowledge of the system *** policy approximation is consistent,i.e.,it does not depend on the action samples used to calculate *** method is appropriate for mechanical systems with high-dimensional input spaces and unknown dynamics performing Constraint-Balancing *** verify it both in simulation and experimentally for an Unmanned Aerial Vehicles(UAVs) carrying a suspended load,and in simulation,for the rendezvous of heterogeneous robots.

关键词： Control systems Nonlinear dynamical systems Robots Vehicle dynamics Function approximation Learning (artificial intelligence)

Recent advances in liver preconditioning: Thyroid hormone, n-3 long-chain polyunsaturated fatty acids and iron

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World Journal of Hepatology 2012年第4期4卷 119-128页

作者： Virginia Fernández Gladys tapia Luis A Videla Molecular and Clinical Pharmacology Program Institute of Biomedical Sciences Faculty of Medicine University of Chile Casilla 70000 Santiago-7 Chile

Liver preconditioning (PC), defined as an enhanced tolerance to injuring stimuli induced by previous specific maneuvers triggering beneficial functional and molecular changes, is of crucial importance in human liver transplantation and major hepatic resection. For these reasons, numerous PC strategies have been evaluated in experimental models of ischemia-reperfusion liver injury, which have not been transferred to clinical application due to side effects, toxicity and difficulties in implementation, with the exception of the controversial ischemic PC. In recent years, our group has undertaken the assessment of alternate experimental liver PC protocols that might have application in the clinical setting. These include thyroid hormone (T3), n-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA), or iron, which suppressed liver damage due to the 1 h ischemia-20 h reperfusion protocol. T3, n-3 LCPUFA and iron are hormetic agents that trigger biologically beneficial effects in the low-dose range, whose multifactorial mechanisms of action are discussed in the work.

关键词： Liver preconditioning Thyroid hormone n-3 polyunsaturated fatty acids Iron

Axonal regeneration after spinal cord injury in zebrafish and mammals: differences, similarities, translation

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Neuroscience Bulletin 2013年第4期29卷 402-410页

作者： Katarina Vajn Jeffery A Plunkett Alexis Tapanes-castillo Martin oudega Departments of Physical Medicine & Rehabilitation University of Pittsburgh School of Science Technology and Engineering Management St. Thomas University Departments of Neurobiology University of Pittsburgh Departments of Bioengineering University of Pittsburgh

Spinal cord injury （SCl） in mammals results in functional deficits that are mostly permanent due in part to the inability of severed axons to regenerate. Several types of growth-inhibitory molecules expressed at the injury site contribute to this regeneration failure. The responses of axons to these inhibitors vary greatly within and between organisms, reflecting axons＇ characteristic intrinsic propensity for regeneration. In the zebrafish （Danio rerio） many but not all axons exhibit successful regeneration after SCI. This review presents and compares the intrinsic and extrinsic determinants of axonal regeneration in the injured spinal cord in mammals and zebrafish. A better understanding of the molecules and molecular pathways underlying the remarkable individualism among neurons in mature zebrafish may support the development of therapies for SCI and their translation to the clinic.

关键词： spinal cord injury axonal regeneration growth inhibition functional recovery zebrafish

A comparative study between ionic liquid coating and counterparts in bulk for toluene absorption

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Green Chemical Engineering 2020年第2期1卷 147-154页

作者： Ventura castillo Ramos Wei Han King Lun Yeung Division of Environment and Sustainability Hong Kong SARChina Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina

The structure-activity relationship(SAR)for toluene absorption and desorption in ionic liquids(ILs)has been investigated for seven commercial ILs in bulk and thin liquid *** with imidazolium cations of different alkyl chain lengths and a Hofmeister series of anions including[CH3COO],[I],[BF4],[HSO4],and[PF6]were *** capacity for toluene increases with increasing kosmotropicity of the cation and anion,while the absorption rate in bulk ILs is governed by viscosity and that in thin ILs layer by the oil-water partition coefficient(Kow).A regenerability coefficient(Rp)measures toluene desorption and IL *** release rate as measured by dRp/dt correlates well with the Kow and viscosity of the ILs and tx,the time required to completely desorb toluene is related to its ionic strength as measured from v(C2H)of the imidazolium *** properties are in turn governed by the kosmotropicity of the cation and anion pair forming the IL.

关键词： Ionic liquids Volatile organic compounds Absorption Air purification Structure-activity relationship

An Inchworm-inspired Robot Based on Modular Body, Electronics and Passive Friction Pads Performing the Two-anchor Crawl Gait

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Journal of Bionic Engineering 2018年第5期15卷 820-826页

作者： Flavio Moreira Anthony Abundis Michael Aguirre Justin castillo Pranav A. Bhounsule Robotics and Motion Laboratory Department of Mechanical Engineering The University of Texas at San Antonio One UTSA Circle San Antonio rX78249 USA

We have created an inchworm robot capable of the two-anchor crawl gait on level ground and inclined plane. The main novelty is in the design of the inchworm：（1） three-part body that is 3D printed and actuated by two servo motors to allow a looping and lengthening action, （2） passive friction pads to anchor the feet, each of which may be disengaged using a servo motor actuated lever arm, and （3） modular body and electronics. The robot is about 2 feet （61 cm） in length, has a mass of about 4 kg, and uses an open-loop controller to achieve steady crawling gait. The inchworm robot achieved a speed of 2.54 *** on level ground as well as on an incline plane of 19~. The energy usage as measured by the Mechanical Cost of Transport （a non-dimensional number defined as the energy used per unit weight per unit distance moved） is 3.34. Our results indicate that simple robotic designs that copy the basic features of natural organisms provide a promising alternative over conventional wheeled robots.

关键词： inchworm bioinspiration two-anchor crawl gait 3D printing sliding locomotion cost of transport

Intelligent windows for electricity generation: A technologies review

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Building Simulation 2022年第10期15卷 1747-1773页

作者： Manlio Salas castillo Xiao Liu Fedaa Abd-AIHamid Karen Connelly Yupeng Wu Department of Architecture and Built Environment Faculty of EngineeringUniversity of NottinghamUniversity Park NottinghamNG7 2RDUK Department of Architecture Faculty of Architecture and DesignAI-Zaytoonah University of JordanAmmanJordan

Buildings are responsible for over 40% of total primary energy consumption in the US and EU and therefore improving building energy efficiency has significant potential for obtaining net-zero energy buildings reducing energy consumption. The concurrent demands of environmental comfort and the need to improve energy efficiency for both new and existing buildings have motivated research into finding solutions for the regulation of incoming solar radiation, as well as ensuring occupant thermal and visual comfort whilst generating energy onsite. Windows as building components offer the opportunity of addressing these issues in buildings. Building integration of photovoltaics permits building components such as semi-transparent façade, skylights and shading devices to be replaced with PV. Much progress has been made in photovoltaic material science, where smart window development has evolved in areas such as semi-transparent PV, electrochromic and thermochromic materials, luminescent solar concentrator and the integration of each of the latter technologies to buildings, specifically windows. This paper presents a review on intelligent window technologies that integrate renewable energy technologies with energy-saving strategies contributing potential solutions towards sustainable zero-energy buildings. This review is a comprehensive evaluation of intelligent windows focusing on state-of-the-art development in windows that can generate electricity and their electrical, thermal and optical characteristics. This review provides a summary of current work in intelligent window design for energy generation and gives recommendations for further research opportunities.

关键词： intelligent window electricity generation photovoltaic building integrated PV solar concentrator electricity-generating smart window

Natural variability of essential oil and antioxidants in the medicinal plant Turnera diffusa

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Asian Pacific Journal of Tropical Medicine 2017年第2期10卷 114-119页

作者： Ana Lucía Urbizu-González Octelina castillo-Ruiz Guillermo Cristian Guadalupe Martínez-Ávila Jorge Ariel Torres-castillo Universidad Autónoma de Tamaulipas Instituto de Ecología AplicadaDivisión del Golfo 356Col.Libertad87019Ciudad VictoriaTamaulipasMéxico Universidad Autónoma de Tamaulipas Unidad Académica Multidisciplinaria Reynosa AztlánCalle 16 y Lago de Chápala s/n Col.AztlánC.P.88740ReynosaTamaulipasMéxico Universidad Autónoma de Nuevo León Facultad de AgronomíaFrancisco Villa s/n.Col.Ex Hacienda El Canadá66050General EscobedoNuevo LeónMéxico

Objective:To evaluate differences in yield and composition of the essential oil and antioxidant contents in *** plants from localities in central region of ***:Samples were collected in Tamaulipas,Mexico in the arid *** oil was obtained through steam distillation and analyzed using *** contents,antioxidant activities using ABTS and ferric reducing antioxidant power(FRAP) methods also were ***:A total of 21 compunds were identified in the essential oils;nevertheless,only Eucalyptol,1,4-Methanocycloocta[d]pyridazine,1,4,4a,5,6,9,10,10a-octahydro-11,11-dimethyl-,(1à,4à,4aà,10aà) y Ethanone,1-(1,3-dimethyl-3-cyclohexen-1-yl) were detected in the three *** contents were registered in the sample from Padrón y Juárez with phenolic content of 33.85 mg GAE/g of dry material and antioxidant activities with ABTS 72.32% and with FRAP 21.33 mg GAE/g of dry *** differences were observed in essential oil,phenolics and antioxidants contents between ***:Results suggest that climatic differences and origin influence the phytochemicals in the medicinal plant ***,and thus,it is worth to consider such effects for industrial and medicinal purposes.

关键词： Essential oil Antioxidants Phytochemicals Chemical variation

A neural network to predict reactor core behaviors

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Nuclear Science and Techniques 2014年第1期25卷 75-80页

作者： Juan Jose Ortiz-Servin David A.Pelta Jose Alejro castillo Instituto Nacional de Investigaciones Nucleares Carretera Mexico Toluca S/NLa Marquesa OcoyoacacEstado de Mexico ETS Ingenieria Informatica y Telecomunicaciones Universidad de GranadaC/Daniel Saucedo Aranda

The global fuel management problem in BWRs(Boiling Water Reactors) can be understood as a very complex optimization problem,where the variables represent design decisions and the quality assessment of each solution is done through a complex and computational expensive *** last aspect is the major impediment to perform an extensive exploration of the design space,mainly due to the time lost evaluating non promising *** this work,we show how we can train a Multi-Layer Perceptron(MLP) to predict the reactor behavior for a given *** trained MLP is able to evaluate the configurations immediately,thus allowing performing an exhaustive evaluation of the possible configurations derived from a stock of fuel lattices,fuel reload patterns and control rods *** our particular problem,the number of configurations is approximately 7.7×10^(10);the evaluation with the core simulator would need above 200 years,while only 100hours were required with our approach to discern between bad and good *** later were then evaluated by the simulator and we confirm the MLP *** good core configurations reached the energy requirements,satisfied the safety parameter constrains and they could reduce uranium enrichment costs.

关键词：神经网络预测行为质量评估堆芯沸水反应堆多层感知器 MLP 优化问题

Activation of non-basalslip in multicomponent Mg alloy

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Journal of Magnesium and Alloys 2022年第2期10卷 629-642页

作者： Hyo-Sun Jang Jong-Kwan Lee Antonio João Seco Ferreira tapia Nack Joon Kim Byeong-Joo Lee Department of Materials Science and Engineering Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea Graduate Institute of Ferrous Technology Pohang University of Science and Technology(POSTECH)Pohang 37673Republic of Korea

Activating non-basalslip is a key method to improve room temperature ductility and formability of Mg ***,the detailed criterion for activation of theslip in multicomponent Mg alloys,which can be utilized in commercial Mg alloys,requires further *** present authors investigated the mechanism and criterion using a molecular statics simulation on dislocation behaviors in multicomponent Mg *** found that if multicomponent Mg alloys have an equivalent dislocation binding intensity to associated binary Mg alloys that are optimized to minimize the critical resolved shear stress anisotropy and thus activate theslip,then the critical resolved shear stress anisotropy between slip systems of the multicomponent Mg alloys can also be minimized,resulting in activation of the*** activation is maximized in multicomponent Mg alloys when alloying a large amount of weak dislocation binding *** was confirmed through experiments that the multicomponent Mg alloys satisfying the above criterion show higher room-temperature tensile elongation and formability than other alloys.

关键词： Mg–Zn–Ca alloy Molecular statics simulation Ductility Formability