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High Power Laser Science and Engineering 2015年第3期3卷 59-65页

作者： T.Nagayama r.C.Mancini D.Mayes r.Tommasini r.Florido Physics Department University of Nevada Lawrence Livermore National Laboratory Departamento de Física Universidad de Las Palmas de Gran Canaria

Temperature and density asymmetry diagnosis is critical to advance inertial confinement fusion(ICF) science. A multimonochromatic x-ray imager, MMI, records the spectral signature from an ICF implosion core with time resolution, 2D spatial resolution and spectral resolution. While narrow-band images and 2D space-resolved spectra from the MMI data constrain the temperature and the density spatial structure of the core, the accuracy of the images and the spectra highly depends on the quality of the MMI data and the processing tools. Here, we synthetically investigate the criterion for reliable MMI diagnostics and its effects on the accuracy of the reconstructed images. The pinhole array tilt determines the object spatial sampling efficiency and the minimum reconstruction width, w. When the spectral width associated with w is significantly narrower than the spectral linewidth, the line images reconstructed from the MMI data become reliable. The MMI setup has to be optimized for every application to meet this criterion for reliable ICF diagnostics.

关键词： high power laser inertial confinement fusion monochromatic imager x-ray diagnostics

Saint-Venant torsion analysis of bars with rectangular cross-section and effective coating layers

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Applied Mathematics and Mechanics(English Edition) 2016年第2期37卷 237-252页

作者： H.TEIMOOrI r.T.FAAL r.DAS Department of Mathematics and Computer Science Allameh Tabatabai University Faculty of Engineering University of Zanjan Department of Mechanical Engineering and Centre for Advanced Composite Materials University of Auckland

This paper investigates the torsion analysis of coated bars with a rectangular cross-section. Two opposite faces of a bar are coated by two isotropie layers with different materials of the original substrate that are perfectly bonded to the bar. With the Saint- Venant torsion theory, the governing equation of the problem in terms of the warping function is established and solved using the finite Fourier cosine transform. The state of stress on the cross-section, warping of the cross-section, and torsional rigidity of the bar are evaluated. Effects of thickness of the coating layers and material properties on these quantities are investigated. A set of graphs are provided that can be used to determine the coating thicknesses and material properties so as to keep the maximum von Mises stress on the cross-section below an allowable value for effective use of the coating layer.

关键词： Saint-Venant torsion rectangular cross-section coating layer torsional rigidity

Seismic behavior of variable frequency pendulum isolator

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Earthquake Engineering and Engineering Vibration 2008年第2期7卷 193-205页

作者： V. r. Panchal r. S. Jangid Department of Civil Engineering Indian Institute of TechnologyBombayPowaiMumbai 400076India

Earthquake performance of a flexible one-story building isolated with a variable frequency pendulum isolator （VFPI） under near-fault and far-field ground motions is investigated. The frictional forces mobilized at the interface of the VFPI are assumed to be velocity dependent. The interaction between frictional forces of the VFPI in two horizontal directions is duly considered and coupled differential equations of motion of the isolated system in the incremental form are solved iteratively. The response of the system with bi-directional interaction is compared with those without interaction. In addition, the effects of velocity dependence on the response of the isolated system are also investigated. Moreover, a parametric study is carried out to critically examine the influence of important parameters on bi-directional interaction effects of the frictional forces of the VFPI. These parameters are： the superstructure time period, frequency variation factor （FVF） and friction coefficient of the VFPI. From the above investigations, it is observed that the dependence of the friction coefficient on relative velocity of the system does not have a noticeable effect on the peak response of the system isolated with VFPI, and that the bi-directional interaction of frictional forces of the VFPI is important and if neglected, isolator displacements will be underestimated and the superstructure acceleration and base shear will be overestimated.

关键词： base isolation bi-directional interaction superstructure flexibility near-fault ground motion friction coefficient far-field ground motion VFPI

Performance-based seismic assessment of a large diameter extended pile shaft in a cohesionless soil

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Earthquake Engineering and Engineering Vibration 2015年第1期14卷 177-188页

作者： Abdoul r.Ghotbi Civil & Environmental Engineering Department University of California

The seismic behavior of a large diameter extended pile shaft founded on a dense sandy site is investigated in this paper. First, a deterministic analysis is conducted including both nonlinear dynamic analysis （NDA） and pushover analysis to gain insights into the behavior of the pile and make sure an appropriate modeling technique is utilized. Then a probabilistic analysis is performed using the results of NDA for various demands. To this end a set of 40 pulse-like ground motions are picked and subsequently 40 nonlinear dynamic and pushover analyses are performed. The data obtained from NDA are used to generate probabilistic seismic demand model （PSDM） plots and consequently the median line and dispersion for each plot are computed. The NDA and pushover data are also plotted against each other to find out to what extent they are correlated. These operations are done for various engineering demand parameters （EDPs）. A sensitivity analysis is done to pick the most appropriate intensity measure （IM） which would cause a minimum dispersion in PSDM plots out of 7 different IMs. Peak ground acceleration （PGA） is found to be the most appropriate IM. Pushover coefficient equations as a function of PGA are proposed which can be applied to the pushover analysis data to yield a better outcome with respect to the NDA. At the end, the pacific earthquake engineering research （PEEr） center methodology is utilized to generate the fragility curves using the properties obtained from PSDM plots and considering various states of damage ranging from minor to severe. The extended pile shaft shows more vulnerability with a higher probability with respect to minor damage compared to severe damage.

关键词： extended pile shaft NDA pushover IMs PSDM fragility functions

Two distinct Paleozoic metamorphic events in the Tarim-North China Collage

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National Science review 2023年第2期10卷 7-8页

作者： Jérémie Soldner State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences CAS Center for Excellence in Deep Earth Science

The Central Asian Or ogenic Belt(CAOB) [1],which includes the Altaids in Central and Northern Asia [2],is the largest accretionary orogen formed during the subduction of the Paleo-Asian Ocean and the Panthalassa Ocean in the period of the Late Proterozoic to Late Paleozoic [3].Closure of the Paleo-Asian Ocean is attributed to the northward drift of the North China and Tarim cratons leading to the massive shortening and oroclinal buckling of the CAOB accretionary system in the Permian [4].

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Towards zero-emission urban mobility:Leveraging AI and LCA for targeted interventions

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Building Simulation 2024年第10期17卷 1653-1657页

作者： Qi r.Wang Department of Civil and Environmental Engineering Northeastern University360 Huntington Ave.BostonMA 02115USA

Urban mobility is a critical contributor to greenhouse gas emissions,accounting for over 30%of urban carbon emissions in the United States in *** this challenge requires a comprehensive and data-driven approach to transform transportation systems into sustainable *** paper presents an integrated framework that leverages artificial intelligence(AI),machine learning(ML),and life cycle assessment(LCA)to analyze,model,and optimize urban *** framework consists of four key components:AI-powered analysis and models,synthetic urban mobility data generation,LCA for environmental footprint analysis,and data-driven policy *** combining these elements,the framework not only deciphers complex mobility patterns but also quantifies their environmental impacts,providing actionable insights for policy decisions aimed at reducing carbon emissions and promoting sustainable urban *** implications of this approach extend beyond individual cities,offering a blueprint for global sustainable urban mobility.

关键词： urban mobility artificial intelligence(AI) life cycle assessment(LCA) sustainable transportation data-driven policy

Why does caloric restriction increase life and healthspan? The ‘clean cupboards’ hypothesis

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National Science review 2020年第7期7卷 1153-1156页

作者： John r.Speakman State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental Biology Chinese Academy of Sciences Institute of Biological and EnvironmentalSciences University of Aberdeen CAS Center of Excellence in Animal Evolution and Genetics Kunming Institute of Zoology Chinese Academy of Sciences

The disposable soma hypothesis explanation of the effects of caloric restriction(Cr) on lifespan fails to explain why Cr generates negative impacts alongside the positive effects and does not work in all species. I pr...

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A semi-supervised hierarchical approach： two-dimensional clustering of microarray gene expression data

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Frontiers of Computer Science 2013年第2期7卷 204-213页

作者： r PrISCILLA S SWAMYNATHAN Department of Information and Science and Technology The College of Engineering Guindy Campus Anna UniversityIndia Chennai 600025

Micro array technologies have become a widespread research technique for biomedical researchers to assess tens of thousands of gene expression values simul- taneously in a single experiment. Micro array data analysis for biological discovery requires computational tools. In this research a novel two-dimensional hierarchical clustering is presented. From the review, it is evident that the previous research works have used clustering which have been ap- plied in gene expression data to create only one cluster for a gene that leads to biological complexity. This is mainly because of the nature of proteins and their interactions. Since proteins normally interact with different groups of proteins in Order to serve different biological roles, the genes that produce these proteins are therefore expected to co express with more than one group of genes. This constructs that in micro array gene expression data, a gene may makes its pres- ence in more than one cluster. In this research, multi-level micro array clustering, performed in two dimensions by the proposed two-dimensional hierarchical clustering technique can be used to represent the existence of genes in one or more clusters consistent with the nature of the gene and its attributes and prevent biological complexities.

关键词： clustering hierarchical clustering supervisedclustering overlapping clustering

Nutritive value of introduced bamboo species in the northwestern Himalayas, India

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Journal of Forestry research 2019年第6期30卷 2051-2060页

作者： D.r.Bhardwaj P.Sharma r.Bishist M.r.Navale r.Kaushal Dr.Y.S.Parmar University of Horticulture and Forestry Solan 173 230India ICAr-Indian Institute of Soil and Water Conservation DehradunUttarakhandIndia

Bamboos are used extensively for a variety of purposes,and many new species have been introduced to the northwestern ***,their potential as a fodder species has not been *** bamboo species,namely Dendrocalamus hamiltonii Gamble,Dendrocalamus asper(*** Schult.f.)Backer ex ***,Melocanna baccifera(roxb.)Kurz,Phyllostachys aurea rivie′re and ***′re,Phyllostachys bambusoides Sieb and *** Phyllostachys pubescens(Pradelle)Mazel ex *** evaluated for their nutritional value,relative palatability and best lopping *** matter(DM),ether extract(EE),and crude fibre varied from(37.0-67.7)%,(4.7-7.6),and(22.1-37.9)%,*** of crude protein ranged from(12.2-17.1)%,total ash(TA)from(11.8-21.5)%,acid insoluble ash(AIA)from(0.3-0.5)%,nitrogen free extract from(31.1-40.8)%,carbohydrates from(57.0-69.0)%,organic matter(OM)from(78.5-88.2)%,calcium from(1.7-2.3)%,phosphorus from(0.4-0.8)%,potassium from,(0.9-1.6)%,magnesium from(0.5-0.9)%,sodium from(603.7-1072.7)×10^-6 and vitamin A from(21.1-30.5)×10^-2 mg/g,*** had maximum values for DM,EE,TA and *** and vitamin A were highest in *** and carbohydrates were maximized in *** and CP in *** the values obtained for different bamboo species were less than maximum tolerable concentration of common feed resources of the region thereby indicating their suitability for nutrition and *** contents of anti-nutritional factors,namely hydrocyanic acid and tannin ranged from(33.8-61.7)×10^-2 mg/g and(0.7-1.9)%,*** was the best species from a palatability point of view and has maximum crude protein content(17.2%),Ca(2.3%)and lowest tannin content(0.7%).The relative palatability of introduced bamboo species followed trend:***(97.6%)[***(92.5%)[***(81.2%)[***(76.9%)[***(75.9%)[***(73.4%).The optimum months for lopping these species for green leaves are Novem

关键词： Anti-nutritional values Nutritional values Bamboo Chemical composition Mineral nutrients Palatability Lopping time

Human-Like robot Sensing Mediated by Body Heat

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Journal of Bionic Engineering 2014年第1期11卷 82-89页

作者： r. Andrew russell Department of Electrical and Computer Systems Engineering Monash University Clayton VIC 3800 Australia

This paper presents a novel robotic sensor system that can monitor volatile chemicals and airflow. The system is modelled on characteristics of the human body that are thought to have a significant influence on the human odour and airflow senses. In particular, the effect of buoyant airflow due to body heat acts to gather volatile chemicals over large areas of the human body and carry them to the nose. It is postulated that this effect increases the receptive area for human olfaction. In addition, the interaction between rising air heated by the body and external airflow produces a temperature distribution about head height that can be used to infer airflow direction and magnitude. A heated sensor system was constructed to investigate these effects and the resulting sensor was mounted on a mobile robot. The design of the sensor system is described. results are presented which demonstrate its ability to measure airflow direction and detect chemical signals over a wider receptive field compared with an unheated sensor.

关键词： sensing volatile chemicals sensing airflow human body heat biomimetic robots