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Online optimal control of nonlinear discrete-time systems using approximate dynamic programming

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控制理论与应用（英文版） 2011年第3期9卷 361-369页

作者： Travis DIERKS Sarangapani JAGANNATHAN drs sustainment systems Inc.201 Evans Lane Department of Electrical and Computer Engineering Missouri University of Science and Technology

In this paper,the optimal control of a class of general affine nonlinear discrete-time(DT) systems is undertaken by solving the Hamilton Jacobi-Bellman(HJB) equation online and forward in *** proposed approach,referred normally as adaptive or approximate dynamic programming(ADP),uses online approximators(OLAs) to solve the infinite horizon optimal regulation and tracking control problems for affine nonlinear DT systems in the presence of unknown internal *** the regulation and tracking controllers are designed using OLAs to obtain the optimal feedback control signal and its associated cost ***,the tracking controller design entails a feedforward portion that is derived and approximated using an additional OLA for steady state *** update laws for tuning the unknown parameters of the OLAs online are *** techniques are used to show that all signals are uniformly ultimately bounded and that the approximated control signals approach the optimal control inputs with small bounded *** the absence of OLA reconstruction errors,an optimal control is *** results verify that all OLA parameter estimates remain bounded,and the proposed OLA-based optimal control scheme tunes itself to reduce the cost HJB equation.

关键词： Online nonlinear optimal control Hamilton Jacobi-Bellman Online approximators Discrete-time systems

Estimating the size and travel distance of Klapperhorn Mountain debris flows for risk analysis along railway, Canada

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International Journal of Sediment Research 2008年第3期23卷 275-282页

作者： C. Derek MARTIN Dept. Civil and Environmental Engineering University of Alberta Edmonton Alberta Canada T6G 2W2Drs.

Debris flows occurring on Klapperhorn Mountain in the Yellowhead Pass in the Canadian Rocky Mountains pose a significant hazard to railway operations at the base of the mountain. The size (volume) and travel distance of these debris flows play an important role in assessing the risk to the railway. GIS analysis, airphoto interpretation together with field work were undertaken on two debris flows located at track mileage 54.0 and 54.3. Characteristics of these two debris flow events were analyzed, including debris flow path morphology and event behavior. Their sizes and travel distances were estimated using an empirical-statistical model (UBCDFLOW) under different initiation conditions. Their potential impact on the railway bridge was evaluated using a bridge blockage ratio.

关键词： Debris flow Size Travel distance Railway

Correlative microscopy of Purkinje cells

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BIOCELL 2012年第1期36卷 1-29页

作者： ORLANDO J.CASTEJÓN Instituto de Investigaciones Biologicas“drs.Orlando Castejón and Haydee Viloria de Castejón”.Facultad de Medicina.Universidad del Zulia.Maracaibo.Venezuela

The Purkinje cell and their synaptic contacts have been described using(1)light microsocopy,(2)transmission and scanning electron microscopy,and freeze etching technique,(3)conventional and field emission scanning electron microscopy and cryofracture methods,(4)confocal laser scanning microscopy using intravital stain FM64,and(5)immunocytochemical techniques for Synapsin-I,PSD9-5,GluR1 subunit of AMPA receptors,N-cadherin,and CamKII *** outer surface and inner content of plasma membrane,cell organelles,cytoskeleton,nucleus,dendritic and axonal processes have been exposed and analyzed in a three-dimensional *** intramembrane morphology,in bi-and three-dimensional views,and immunocytochemical labeling of synaptic contacts with parallel and climbing fibers,basket and stellate cell axons have been *** etching technique,field emission scanning microscopy and cryofracture methods,and GluR1 immunohistochemistry showed the morphology and localization of postsynaptic *** cell shows N-cadherin and CamKII alpha *** correlative microscopy approach provides a deeper understanding of structure and function of the Purkinje cell,a new three-dimensional outer and inner vision,a more detailed study of afferent and intrinsic synaptic junctions,and of intracortical circuits.

关键词： cerebellar cells synaptic contacts electron microscopy immunohistochemistry

Chordoma in Nasopharynx in a 70-Year-Old Female: A Rare Occurence

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International Journal of Otolaryngology and Head & Neck Surgery 2014年第6期3卷 342-346页

作者： Bhaskar Mitra Subhalakshmi Sengupta Anshita Rai Jay Mehta Aruna Rai Quader Subhendu Roy Anita Borges drs. Tribedi & Roy Diagnostic Laboratory Kolkata India

The nasopharynx is an unusual site for extraosseous chordoma. The characteristic histology and immunohistochemistry confirmed the diagnosis. The behaviour of this tumour is locally aggressive. We report a case of naso... 详细信息

关键词： Chordoma Nasopharyngeal Tumours Notochord

On the viability of wearing evaluation by Thin Layer Activation in the presence of non-occupationally exposed individuals

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Nuclear Science and Techniques 2022年第3期33卷 103-112页

作者： Michel de Almeida Franca Julio Cezar Suita Paulo Fernando Ferreira Frutuoso e Melo Celso Marcelo Franklin Lapa Graduate Program of Nuclear Engineering COPPEFederal University of Rio de JaneiroRio de JaneiroRJ 21941914Brazil Instituto de Engenharia Nuclear(IEN-CNEN) Rio de Janeiro 21941614Brazil Comissao Nacional de Energia Nuclear(SEASE/drs/CNEN) Rio de Janeiro 22290040Brazil

Thin Layer Activation is a nuclear technique that has key advantages over other wear measuring techniques for mechanical systems,especially for in site experiments on equipment important to safety in nuclear ***,it incurs radioactive dose and,thus,must be proved radiologically safe before use,otherwise,the utilization of this technique may be hindered *** said technique is safe previous to any operational/monetary cost is key,providing a methodology for this early assertion is the main contribution of this work—here,only non-occupationally exposed individuals are *** work offers a methodology,through a case study,to ascertain the Thin Layer Activation parameters to obtain safe levels of radioactive dose while maintaining statistically reliable *** methodology consists of using simulations,through the Monte Carlo Method,to obtain the floors and ceilings for the previously mentioned activation parameters based on operation and work conditions on site.

关键词： Thin Layer Activation Safety evaluation Simulation Equipment wearing

New insights into disruption of iron homeostasis by environmental pollutants

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Journal of Environmental Sciences 2015年第8期27卷 256-258页

作者： Xiang Wang Tian Xia Department of Medicine Division of Nano Medicine University of California California Nano systems Institute University of California

Among the numerous health conditions environmental pollutants can cause, chronic exposure to pollutants including persistent organic pollutants（POPs） and heavy metals has been shown to disturb a specific biological homeostatic process, the iron metabolism in human body. Disorders of iron metabolism are among the common diseases of humans and encompass a broad spectrum of diseases with different clinical manifestations, ranging from anemia to iron overload, and possibly to neurodegenerative diseases and ***–ferroportin（FPN） signaling is one of the key mechanisms responsible for iron supply, utilization, recycling, and storage, and recent studies demonstrated that exposure to environmental pollutants including POPs and heavy metals could lead to disruption of the hepcidin–FPN axis along with disordered systemic iron homeostasis and diseases. This article introduces and highlights the accompanying review article by drs. Xu and Liu in this journal, which elaborates in detail the adverse effects of environmental pollutants on iron metabolism, and the mechanisms responsible for these toxicological outcomes. It also points out the knowledge gaps still existing in this subject matter. Research that will fill these gaps will improve our understanding of the issue and provide useful information to prevent or treat diseases induced by environmental pollutants.

关键词： Environmental pollution Persistent organic pollutants Heavy metals Iron homeostasis Hepcidin Ferroportin

Relationship between acoustic measures of voice and judgments of voice quality

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中国眼耳鼻喉科杂志 2000年第1期 49-51,33页

作者： Daniel Zaoming Huang Ph. D. Tiger drs Inc. PO Box 75063 Seattle WA 98125 USA

1. Introduction The goal of the present study was to develop non-in-vasive techniques for the assessment of voice disorders andfor monitoring the effects of voice. However, before acous-tic algorithms can be used in clinical applications, it isimportant to understand the relationship between clinicalperceptions of voice quality and the acoustic measures ob-

关键词：耳鼻喉科刀片杂志

Design and simulation of gas burner ejectors

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Carbon Resources Conversion 2021年第1期4卷 28-35页

作者： Mario Pichler Florian Wesenauer Christian Jordan Stefan Puskas Bernhard Streibl Franz Winter Michael Harasek Institute of Chemical Environmental&Bioscience EngineeringTU WienGetreidemarkt 9/1661060 ViennaAustria Wienerberger AG Wienerbergerplatz 11100 ViennaAustria drs3–Strömungsberechnung und Simulation e.U. Simmeringer Hauptstraße 397/1411110 ViennaAustria

Ignition within gas burner ejectors can lead to off design conditions and has significant influence on the burner *** ignition in the ejector should be *** the present study the influence of combustion reactions on the performance of gas burner injectors is *** investigate if ignition is possible,simulated ignition delay times,using a detailed reaction mechanism,are compared to predicted mean residence times of the gas in the *** burner ejectors are designed using one dimensional analytic equations,based on energy and momentum conservation equations and conventional isentropic equations.1D results are compared to 2D computational fluid dynamics(CFD)simulations,to take into account non-ideal mixing effects along the *** are validated with experiments with air at room temperature.1D results show very good agreement not only with CFD simulations for the case of non-reactive flows,but also with performed *** is shown that the assumption of ideal mixing along the ejector and thus the comparison of the ignition delay time to the gas mean residence time,to predict ignition in the ejector,is not *** in the ejector is possible,even if the ignition delay time is more than thirty times higher than the mean residence *** addition to that,it is shown,that ignition and the choice of reaction mechanism have significant influence on the predicted gas burner ejector ***,the accurate prediction of ignition delay time and the use of a detailed reaction kinetic are mandatory to correctly predict the burner ejector behavior.

关键词： Self-ignition Flammability limits Reacting jet Ejector Jet pump Computational fluid dynamics

药物性放大内镜:利用微血管对肾上腺素刺激的反应辨别早期胃癌

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世界核心医学期刊文摘（胃肠病学分册） 2006年第11期2卷 27-28页

作者： Fukui H. Shirakawa K. Nakamura T. 王晓君 Current affiliations: Dept. of Surgical andMolecular Pathology (drs Fukui Suzuki and Fujimori) Department of Endoscopy (Drs Shirakawa and Nakamura) Department of Gastroenterology (Drs Masuyama Hiraishi and Terano) Tochigi Japan Dr.

Background: Magnifying endoscopy is a promising modality for fine observation of minute surface structures and microvessel architecture in gastric lesions. Objective: To observe the response of microvessels to epinephrine stimulation in early gastric cancer tissues and to assess the usefulness of magnifying pharmacoendoscopy for histologic diagnosis. Design: This was a prospective pilot study. Setting: This study was conducted at an academic hospital. Patients: Twenty-nine patients with differentiated early gastric cancer were enrolled. Interventions: Microvessels in both the cancerous lesion and its adjacent non-neoplastic gastric mucosa were observed by magnifying endoscopy before and after focal spray with epinephrine solution (0.05 mg/mL).Main Outcome Measurements and Results: After epinephrine stimulation, noncancerous gastric mucosa surrounding the cancerous lesion showed a change in color from red to white; no microvessels were evident. On the other hand, all the cancerous lesions examined clearly showed enhancement of tumor microvessels. The rate of detection of tumor microvessels by magnifying pharmacoendoscopy (100%) was significantly higher than that by magnifying endoscopy alone (41.3%). Limitations: This was small pilot study. Conclusions: Magnifying pharmacoendoscopy with epinephrine is a powerful tool for assessing tumor vascularity and may contribute to the histologic diagnosis of differentiated early gastric cancers before endoscopic treatment.

关键词：早期胃癌癌性微血管结构肿瘤微血管组织学诊断微小结构病变黏膜教学医院肿瘤血管结果指标