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Some highlights of the Gamma-ray first four years of the Fermi Space Telescope

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Frontiers of physics 2013年第6期8卷 693-713页

作者： steven Ritz Department of Physics and the SCIPP University of California Santa Cruz Santa Cruz CA 95064 USA

The Fermi Gamma-ray Space Telescope, formerly called GLAST, measures the cosmic gamma-ray flux in the energy range 8 keV to 〉 300 GeV. In addition to breakthrough capabilities in energy coverage and localization, the very large field of view enables observations of 20~ of the sky at any instant, and the entire sky on a timescale of a few hours. With its launch in 2008, Fermi opens a new and important window on a wide variety of phenomena, including pulsars, black holes and active galactic nuclei, gamma-ray bursts, supernova remnants and the origins of cosmic rays, and searches for hypothetical new phenomena such as particle dark matter annihilations. A brief overview and selected science highlights from the first four years are provided.

关键词： high-energy gamma-ray astrophysics dark matter fundamental physics tests spacebased astrophysics space-based particle astrophysics gamma-ray bursts blazars pulsars

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翼龙牙齿显微结构初步分析(英文)

地球学报 2010年第S1期31卷 70-72页

作者： steven u.VIDOVIC Palaeobiology Research Group School of Earth and Environmental SciencesUniversity of PortsmouthPortsmouthU.K.

The Pterosauria display an extremely wide range of dental variation from multi-cusped, laterally com-pressed crowns in basal forms, to the fang-like teeth of ornithocheirids.

关键词：显微结构初步分析翼龙牙齿

A hybrid Monte Carlo study of bond-stretching electron–phonon interactions and charge order in BaBiO_(3)

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npj Computational Materials 2023年第1期9卷 1950-1958页

作者： Benjamin Cohen-Stead Kipton Barros Richard Scalettar steven Johnston Department of Physics and Astronomy The University of TennesseeKnoxvilleTN 37996USA Institute for Advanced Materials and Manufacturing The University of TennesseeKnoxvilleTN 37996USA Theoretical Division and CNLS Los Alamos National LaboratoryLos AlamosNM 87545USA Department of Physics and Astronomy University of CaliforniaDavisCA 95616USA

The relationship between electron–phonon(e-ph)interactions and charge-density-wave(CDW)order in the bismuthate family of high-temperature superconductors remains *** address this question using nonperturbative hybrid Monte Carlo calculations for the parent compound BaBiO_(3).Our model includes the Bi 6s and O 2pσorbitals and coupling to the Bi-O bond-stretching branch of optical phonons via modulations of the Bi-O hopping *** simulate three-dimensional clusters of up to 4000 orbitals,with input model parameters taken from ab initio electronic structure calculations and a phonon energyℏΩ0=60 *** results demonstrate that the coupling to the bond-stretching modes is sufficient to reproduce the CDW transition in this system,despite a relatively small dimensionless *** also find that the transition deviates from the weak-coupling Peierls’*** work demonstrates that off-diagonal e-ph interactions in orbital space are vital in establishing the bismuthate phase diagram.

关键词： stretching phonon charge

A Fusion Steganographic Algorithm Based on Faster R-CNN

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Computers, Materials & Continua 2018年第4期55卷 1-16页

作者： Ruohan Meng steven G.Rice Jin Wang Xingming Sun School of Computer and Software Nanjing University of Information Science and TechnologyNing Liu RoadNo.219Nanjing210044China Jiangsu Engineering Centre of Network Monitoring Ning Liu RoadNo.219Nanjing210044China Department of Mathematics and Computer Science Northeastern State University TahlequahOK 74464USA School of Computer&Communication Engineering Changsha University of Science&TechnologyChangsha410114China

The aim of information hiding is to embed the secret message in a normal cover media such as image,video,voice or text,and then the secret message is transmitted through the transmission of the cover *** secret message should not be damaged on the process of the cover *** order to ensure the invisibility of secret message,complex texture objects should be chosen for embedding *** this paper,an approach which corresponds multiple steganographic algorithms to complex texture objects was presented for hiding secret ***,complex texture regions are selected based on a kind of objects detection ***,three different steganographic methods were used to hide secret message into the selected block *** results show that the approach enhances the security and robustness.

关键词： Faster R-CNN fusion steganography object detection CNNs information hiding.

Building durable climate clubs:Lessons from a comparative study of the APP and CEM

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Chinese Journal of Population,Resources and Environment 2021年第2期19卷 117-124页

作者： Bowen Yu steven Bernstein Matthew Hoffmann School of International Relations and Public Affairs Fudan UniversityShanghai200433China Department of Political Science the University of TorontoTorontoM5S 3G3Canada

Climate clubs are valuable platforms for international and public-private collaboration in global climate governance;however,not all climate clubs enjoy durable support from their *** existing literature attributes the varied fates of climate clubs to factors like legitimacy and club *** further argue that the norm-making function of clubs,the perceived value of club goods,and the costs of club good production collectively affect club *** present a comparative study on two u.S.-initiated climate clubs-the Asia-Pacific Partnership on Clean Development and Climate(APP)and the Clean Energy Ministerial(CEM).While legitimacy concerns had some marginal influence on both clubs,the niche clubs occupy and the costs of club goods provision were crucial factors that influenced the two clubs’different *** APP’s failure was due to its focus on norm-making and providing information-oriented assistance to the private *** government interest in norm-making declined,the APP’s value declined ***,assistance to private sector actors was costly and less attractive to *** comparison,the CEM found its niche by focusing on facilitating policymaking in the clean energy sector in a cost-efficient *** make clubs durable,constructing an action-oriented working environment and providing value-added and low-cost services to key stakeholders are of great importance.

关键词： Climate club Legitimacy Club goods APP CEM

Innovations in the diagnosis and management of uveitis: promising research to address unmet patient needs

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Annals of Eye Science 2022年第1期7卷 1-7页

作者： steven Yeh Ye Huang Joanne Thomas Truhlsen Eye Institute University of Nebraska Medical CenterOmahaNEUSA Emory Eye Center Emory University School of MedicineAtlantaGAUSA Medical College of Georgia AugustaGAUSA.

uveitis,or inflammation of the uveal tissues(iris,ciliary body and the choroid),and its contiguous structures,can lead to severe visual impairment and is among the leading causes of vision impairment worldwide(1).In clinical practice,specialists in uveitis and ocular immunology are called upon to manage a range of uveitis syndromes-infectious disease,noninfectious autoimmune conditions,and masquerade syndromes such as ***,ophthalmologists of all subspecialties(i.e.,medical and surgical retina,corneal surgeons,orbital/oculoplastic surgeons,and comprehensive ophthalmologists)are called upon to manage uveitis syndromes,emphasizing clear importance to understanding common uveitis syndromes,diagnostic workups,and the state-of-the-art in uveitis and ocular inflammation care.

关键词： uveitis inflammation diagnosis

Competition and abiotic stress affect the size of mangroves near their geographic range limit

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Journal of Plant Ecology 2022年第1期15卷 129-140页

作者： Dan Peng Hongyu Guo Anna R.Armitage steven C.Pennings Department of Biology and Biochemistry University of HoustonHoustonTX 77204USA Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems College of the Environment and EcologyXiamen UniversityXiamen 361102China Tianjin Key Laboratory of Animal and Plant Resistance College of Life SciencesTianjin Normal UniversityTianjin 300387China Department of Marine Biology Texas A&M University at GalvestonGalvestonTX 77553USA

Studies of competition in mangroves are mostly limited to seedlings and artificial settings like forestry *** conducted the first experimental study of intraspecific competition among adult mangroves in a natural mangrove forest to examine how important competition is in determining tree size compared with abiotic *** conducted a study near Port Aransas,TX,uSA,which is near the geographical limit of mangroves and dominated by monospecific stands of‘scrub’form black mangroves,Avicennia *** thinned 10 plots to create a gradient of mangrove cover,and quantified the effects of mangrove cover on the growth of tagged mangroves from 2013 to 2019,and the mangrove canopy height in *** relative growth rate of tagged mangroves declined as mangrove cover increased,and plants in the plot with 100%mangrove cover did not grow,indicating that they had attained their maximum *** plots with reduced mangrove cover,plant height increased sharply,with plants in the plot with 11%mangrove cover growing~52%taller over 6 *** height was~30%taller in the plot fringe than in the interior,and canopy height in both fringe and interior declined as mangrove cover *** of leaf chlorophyll concentration and light interception suggested that plants were primarily limited by *** results showed that scrub mangroves compete strongly despite being limited by abiotic conditions,and that the importance of competition was greater in magnitude than that of abiotic differences between the fringe and interior.

关键词： competition adult mangrove nutrient limitation growth response scrub mangrove geographical limit

Distributed sparse bundle adjustment algorithm based on three-dimensional point partition and asynchronous communication

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Frontiers of Information Technology & Electronic Engineering 2018年第7期19卷 889-904页

作者： Xiao-long SHEN Yong DOu steven MILLS David M EYERS Huan FENG Zhiyi HuANG College of Computer National University of Defense Technology Science and Technology on Parallel and Distributed Laboratory National University of Defense Technology Department of Computer Science University of Otago Department of Computer Science Tsinghua University

Sparse bundle adjustment(SBA) is a key but time-and memory-consuming step in three-dimensional(3 D) reconstruction. In this paper, we propose a 3 D point-based distributed SBA algorithm(DSBA) to improve the speed and scalability of SBA. The algorithm uses an asynchronously distributed sparse bundle adjustment(A-DSBA)to overlap data communication with equation computation. Compared with the synchronous DSBA mechanism(SDSBA), A-DSBA reduces the running time by 46%. The experimental results on several 3 D reconstruction datasets reveal that our distributed algorithm running on eight nodes is up to five times faster than that of the stand-alone parallel SBA. Furthermore, the speedup of the proposed algorithm(running on eight nodes with 48 cores) is up to41 times that of the serial SBA(running on a single node).

关键词： Sparse bundle adjustment Parallel Distributed sparse bundle adjustment Three-dimensional reconstruction Asynchronous

Real-Time Optimal Reach-Posture Prediction in a New Interactive Virtual Environment

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Journal of Computer Science & Technology 2006年第2期21卷 189-198页

作者：杨景周 R. Timothy Marler steven Beck Karim Abdel-Malek Joo Kim uS Army Virtual Soldier Research (VSR) Program Center for Computer-Aided Design The University of Iowa 111 Engineering Research Facility Iowa City IA 52242-1000 U.S.A.

Human posture prediction is a key factor for the design and evaluation of workspaces, in a virtual environment using virtual humans. This work presents a new interface and virtual environment for the direct human optimized posture prediction （D-HOPP） approach to predicting realistic reach postures of digital humans, where reach postures entail the use of the torso, arms, and neck. D-HOPP is based on the contention where depending on what type of task is being completed, and human posture is governed by different human performance measures. A human performance measure is a physics-based metric, such as energy or discomfort, and serves as an objective function in an optimization formulation. The problem is formulated as a single-objective optimization （SO0） problem with a single performance measure and as multiobjective-optimization （MOO） problem with multiple combined performance measures. We use joint displacement, change in potential energy, and musculoskeletal discomfort as performance measures. D-HOPP is equipped with an extensive yet intuitive user-interface, and the results are presented in an interactive virtual environment.

关键词： reach posture prediction MOO human modeling and simulation virtual environment