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Optimal regulation of uncertain dynamic systems using adaptive dynamic programming

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Journal of Control and Decision 2014年第3期1卷 226-256页

作者： hao xu Qiming Zhao S.Jagannathan Department of Electrical and Computer Engineering Missouri University of Science and TechnologyRollaMOUSA

In this tutorial paper,the finite-horizon optimal adaptive regulation of linear and nonlinear dynamic systems with unknown system dynamics is presented in a forward-in-time manner using adaptive dynamic programming(ADP).An adaptive estimator(AE)is introduced with the idea of Q-learning to relax the requirement of system dynamics in the case of linear system,while neural network-based identifier is utilised for nonlinear *** time-varying nature of the solution to the Bellman/Hamilton–Jacobi–Bellman equation is handled by utilising a time-dependent basis function,while the terminal constraint is incorporated as part of the update law of the AE/Identifier in solving the optimal feedback *** an initial admissible control,the proposed optimal regulation scheme of the uncertain linear and nonlinear system yields a forward-in-time and online solution without using value and/or policy *** adaptive observer is utilised for linear systems in order to relax the need for state availability so that the optimal adaptive control design depends only on the reconstructed ***,the optimal control is covered for nonlinear-networked control systems where in the feedback loop is closed via a communication *** of the proposed approach is verified by simulation *** end result is a variant of a roll-out scheme in ADP wherein an initial admissible policy is selected as the base policy and the control policy is enhanced using a one-time policy improvement at each sampling interval.

关键词： adaptive dynamic programming finite horizon optimal control

Immunological function of familial Mediterranean fever disease protein Pyrin

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Science China(Life Sciences) 2014年第12期57卷 1156-1161页

作者： YANG Jie Ling xu hao Shao Feng National Institute of Biological Sciences National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences

Pyrin,encoded by MEFV gene,is conserved in humans and *** in the MEFV gene are associated with the human autoinflammatory disease familial Mediterranean fever(FMF).Pyrin can interact with the inflammasome adaptor ASC and induce inflammatory caspase-1 activation in monocytic cells,but the physiological function of Pyrin has been unknown for many *** we summarize previous studies of Pyrin function under the context of FMF and immunity,and discuss a recent study demonstrating that Pyrin forms an inflammasome complex for caspase-1 activation in innate *** inflammasome detects inactivating modifications of host Rho GTPases by diverse bacterial toxins and infections,including Clostridium difficile glucosylating cytotoxin Tcd B,FIC-domain adenylyltransferase effectors from Vibrio parahaemolyticus and Histophilus somni,ADP-ribosylating Clostridium botulinum C3 toxin as well as Burkholderia cenocepacia *** mode of Pyrin action,i.e.,sensing pathogen virulence activity rather than directly recognizing a microbial molecule,represents a new paradigm in innate immunity.

关键词： Pyrin MEFV Rho GTPase inflammasome Guard Model

Study of Serum Metabonomics and Formula-Pattern Correspondence in Coronary Heart Disease Patients Diagnosed as Phlegm or Blood Stasis Pattern Based on Ultra Performance Liquid Chromatography Mass Spectrometry

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Chinese Journal of Integrative Medicine 2018年第12期24卷 905-911页

作者： LU Xiao-yan xu hao Zhao Tie LI Geng Department of Integrative Cardiology China-Japan Friendship Hospital Cardiovascular Diseases Center Xiyuan HospitalChina Academy of Chinese Medical Sciences

Objectives： To study the characteristics of serum metabonomics in coronary heart disease （CHD） patients diagnosed as phlegm or blood stasis pattern and explore effects of formula-pattern correspondence treatment. Methods： A total of 102 stable CHD patients were enrolled and divided into phlegm group （P group, n=52） and blood stasis group （BS group, n=50） according to pattern identification. Gualou Xiebai Banxia Decoction （瓜萎薤白半夏汤, GXBD） and xuefu Zhuyu Decoction （血府逐瘀汤, XZD） were used as drug interventions. Relevant indicators of metabonomics were observed by ultra performance liquid chromatography mass spectrometry （UPLC-MS） and pattern recognition. Results： Levels of amino acids and phosphatidylethanolamine （PE） in the CHD group were much higher than those in healthy control group, while the levels of unsaturated fatty acids, sphingosine, Lyso, phosphatidylcholine （PC） were significantly lower （P〈0.01）. Most of the differential metabolites between the CHD and the healthy groups were also common metabolites of phlegm and blood stasis. 7（Z）, 10（Z）- hexadecadienoic acid and DPA were decreased in the P group and increased in the BS group. According to the quantity of retraced metabolites, improvement in metabonomics by formula-pattern correspondence was superior to that without correspondence in the BS group. Based on the varieties of metabolites, GXBD could improve the levels of docosapentaenoic acid （DPA）, sphingomyelin （SM）（d34：1）, and L-Lactic acid and XZD could ameliorate the levels of sphingosine and Vit E in the P group, in the BS group, GXBD could improve vitamin E level and XZD could make improvements in the levels of octadecanoic acid, phosphoglycerol, and SM （d34：1）. Conclusions： Phlegm and blood stasis in CHD patients present specific differential metabolites, and share common metabolites. Remarkable differences have been displayed in pathological properties and severity of phlegm and blood stasis. Patients with phlegm are more likely to have lipid metabo

关键词： ultra performance liquid chromatography mass spectrometry metabonomics phlegm/stasis pattern in coronary heart disease disease-pattern combination formula-pattern correspondence

Experimental Research of Surface Roughness Effects on Highly-Loaded Compressor Cascade Aerodynamics

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Journal of Thermal Science 2014年第4期23卷 307-314页

作者： CHEN Shao-wen xu hao WANG Song-tao WANG Zhong-qi Energy Science and Engineering School Harbin Institute of Technology

Aircraft engines deteriorate during continuous operation under the action of external factors including fouling, corrosion, and abrasion. The increased surface roughness of compressor passage walls limits airflow and leads to flow loss. However, the partial increase of roughness may also restrain flow separation and reduce flow loss. It is necessary to explore methods that will lower compressor deterioration, thereby improving the overall performance. The experimental research on the effects of surface roughness on highly loaded compressor cascade aerodynamics has been conducted in a low-speed linear cascade wind tunnel. The different levels of roughness are arranged on the suction surface and pressure surface, respectively. Ink-trace flow visualization has been used to measure the flow field on the walls of cascades, and a five-hole probe has been traversed across one pitch at the outlet. By comparing the total pressure loss coefficient, the distributions of the secondary-flow speed vector, and flow fields of various cases, the effects of surface roughness on the aerodynamics of a highly loaded compressor cascade are analyzed and discussed. The results show that adding surface roughness on the suction surface and pressure surface make the loss decrease in most cases. Increasing the surface roughness on the suction surface causes reduced flow speed near the blade, which helps to decrease mixing loss at the cascades outlet. Meanwhile, adding surface roughness on the suction surface restrains flow separation, leading to less flow loss. Various levels of surface roughness mostly weaken the flow turning capacity to various degrees, except in specific cases.

关键词： Highly loaded compressor linear cascades surface roughness aerodynamic performance experimental research

InGaP/InGaAs/GaAs DHBT structural materials grown by GSMBE

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Rare Metals 2006年第Z2期25卷 20-23页

作者： AI Likun xu Anhuai SUN hao ZHU Fuying QI Ming State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China Graduate School of Chinese Academy of Sciences Beijing 100039 China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China

Heterojunction bipolar transistor (HBT) is of great interest for the application to microwave power and analog circuits. As known, decreasing bandgap energy of the base layer in HBT can result in a smaller turn-on voltage. Using InGaAs as a base material in GaAs HBT is a possible approach to achieve the aim. In this work, a novel InGaP/InGaAs/GaAs double heterojunction bipolar transistor (DHBT) structure with an InGaAs base was designed and grown by gas source molecular beam epitaxy (GSMBE). High-quality InGaAs/GaAs hetero epi-layers and a good doping figure were obtained through optimizing the layer structure and the growth condition. The DHBT devices of a 120 μm×120 μm emitter area were fabricated by normal process and the good DC performance was obtained. A breakdown voltage of 10 V and an offset voltage of just 0.4 V were achieved. These results indicate that the InGaP/InGaAs/GaAs DHBT is suitable for low power-dissipation and high power applications.

关键词： double heterojunction bipolar transistor (DHBT) gas source molecular beam epitaxy (GSMBE) gallium arsenic (GaAs) indium gallium arsenic (InGaAs)

Al-containing Ge-rich IWV:rapid synthesis via interzeolite transformation and application in Baeyer-Villiger oxidation

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Science China Chemistry 2024年第7期67卷 2282-2291页

作者： Meichen Jiao Chunmin Jia hao xu Peng Wu Xian-Ming Zhang School of Chemistry&Material Science Shanxi Normal UniversityTaiyuan 030006China Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China School of Chemistry Taiyuan University of TechnologyTaiyuan 030024China

Ge-containing Lewis acidic zeolites are typically synthesized using a conventional hydrothermal strategy from amorphous silica sources,through a long time-and energy-consuming approach limiting their wide *** study reports a rapid synthesis strategy for a series of IWV aluminogermanosilicate zeolites(T-x-Al)with a wide range of Si/Ge molar ratios(5–15)by interzeolite transformation of dealuminated FAU(DA-FAU).Notably,Ge-rich IWV could be obtained with crystallization time as short as one day by the equimolecular Si/Ge ratio *** effect of synthetic parameters was investigated and the obtained T-x-Al samples were characterized by XRD,SEM,EDS,ICP,^(29)Si and^(27)Al MAS NMR,FTIR,and N_(2)physisorption *** with a previously reported IWV germanosilicate(H-3),T-x-Al displayed a better catalytic activity in Baeyer-Villiger(BV)oxidation,attributed to the presence of the active framework Ge sites with the assistance of the extraframework Al *** cyclic catalysis tests revealed that the presence of framework Al species contributed to the stability of the ***,T-x-Al,with 14-membered ring(MR)supercages,outperformed the typical 12-MR Sn-beta catalyst in the BV oxidation of large ketone-like 2-admantanone,indicating a promising potential application in the macromolecular catalytic process.

关键词： Ge-rich IWV interzeolite transformation Al assistance Baeyer-Villiger oxidation

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Multi-bond Network Hydrogels with Robust Mechanical and Self-healable Properties

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Chinese Journal of Polymer Science 2017年第10期35卷 1253-1267页

作者： xiao-ying liu ming zhong fu-kuan shi hao xu 谢续明 Laboratory of Advanced Materials (Ministry of Education) Department of Chemical Engineering Tsinghua University Beijing 100084 China

Multi-bond network（MBN） which contains a single network with hierarchical cross-links is a suggested way to fabricate robust hydrogels. In order to reveal the roles of different cross-links with hierarchical bond energy in the MBN, here we fabricate poly（acrylic acid） physical hydrogels with dual bond network composed of ionic cross-links between carboxylFe3＋ interactions and hydrogen bonds, and compare these dually cross-linked hydrogels with singly and ternarily cross-linked hydrogels. Simple models are employed to predict the tensile property, and the results confirm that the multi-bond network with hierarchical distribution in the bond energy of cross-links endows hydrogel with effective energy-dissipating mechanism. Moreover, the dually cross-linked MBN gels exhibit excellent mechanical properties（tensile strength up to 500 k Pa, elongation at break ~ 2400%） and complete self-healing after being kept at 50 °C for 48 h. The factors on promoting self-healing are deeply explored and the dynamic multi-bonds are regarded to trigger the self-healing along with the mutual diffusion of long polymer chains and ferric ions.

关键词： responsive Janus PNIPAM irradiation polymerization hence hydrogel heating linking colorful

Optimize Evacuation Route Considering the Operational Cost as a Constraint

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International Journal of Transportation Science and Technology 2013年第1期2卷 65-78页

作者： hao xu Hongchao Liu Department of Civil&Environmental Engineering Texas Tech UniversityLubbockTX 79409

Evacuation planning involves modeling,operation,and management of evacuation routes before and during emergency *** paper presents the development and examination of a route optimization model which considers the operational cost as a *** study is focused on the situation when the backbone evacuation route,usually the interstate highway system,is over congested and some traffic need to be directed to local street *** intersections are the key control components of a street network,traffic operations at intersections cannot be neglected in route *** order to consider the operational cost in the modeling process,a street network is first presented by an extended graph network which has cost information associated with each ***,a system optimal traffic assignment approach is used to select and optimize the evacuation *** property of the approach is examined by a numerical test which includes a network composed of a backbone interstate highway and a grid network with over 30 intersections.

关键词： network intersection backbone

Research on extraction and reproduction of deformation camouflage spot based on generative adversarial network model

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Defence Technology（防务技术） 2020年第3期16卷 555-563页

作者： Xin Yang Wei-dong xu Qi Jia Ling Li Wan-nian Zhu Ji-yao Tian hao xu National Key Laboratory of Lightning Protection and Electromagnetic Camouflage Amy Engineering UniversityNanjingJiangsu210007China Teaching and Research Office of Camouflage in Training Center Army Engineering UniversityXuzhouJiangsu221004China

The method of describing deformation camouflage spots based on feature space has some shortcomings,such as inaccurate description and difficult *** on the strong fitting ability of the generative adversarial network model,the distribution of deformation camouflage spot pattern can be directly fitted,thus simplifying the process of spot extraction and *** requirements of background spot extraction are analyzed *** calculation formula of limiting the range of image spot pixels is given and two kinds of spot data sets,forestland and snowfield,are *** feature is decomposed into shape,size and color features,and a GAN(Generative Adversarial Network)framework is *** effects of different loss functions on network training results are analyzed in the *** the meantime,when the input dimension of generator network is 128,the balance between sample diversity and quality can be *** effects of sample generation are investigated in two ***,the probability of the generated spots being distinguished in the background is counted,and the results are all less than 20% and mostly close to ***,the features of the spot shape are calculated and the independent sample T-test is applied to verify that the features are from the same distribution,and all the P-Values are much higher than *** subjective and objective methods prove that the spots generated by this method are similar to the background *** proposed method can directly generate the desired camouflage pattern spots,which provides a new technical method for the deformation camouflage pattern design and camouflage effect evaluation.

关键词： Deformation camouflage Generative adversarial network Spot feature Shape description