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The Impact of satellite Radiance Data Assimilation within a Frequently Updated Regional Forecast system Using a GsI-based Ensemble Kalman Filter

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Advances in Atmospheric sciences 2019年第12期36卷 1308-1326页

作者： Kefeng ZHU Ming XUE Yujie PAN Ming HU stanley G. benjamin stephen s. WEYGANDT Haidao LIN Key Laboratory of Mesoscale severe Weather/Ministry of Education and school of Atmospheric sciences Nanjing UniversityNanjing 210023China Center for Analysis and Prediction of storms University of OklahomaNorman Oklahoma 73072USA Nanjing University of Information science and Technology Nanjing 210094China NOAA Earth system Research Laboratory BoulderCO 80305USA Cooperative Institute for Research in Environmental sciences University of Colorado BoulderCO 80309USA

A regional ensemble Kalman filter (EnKF) data assimilation (DA) and forecast system was recently established based on the Gridpoint statistical Interpolation (GsI) analysis system. The EnKF DA system was tested with continuous threehourly updated cycles followed by 18-h deterministic forecasts from every three-hourly ensemble mean analysis. Initial tests showed negative to neutral impacts of assimilating satellite radiance data due to the improper bias correction procedure. In this study, two bias correction schemes within the established EnKF DA system are investigated and the impact of assimilating additional polar-orbiting satellite radiance is also investigated. Two group experiments are conducted. The purpose of the first group is to evaluate the bias correction procedure. Two online bias correction methods based on GsI 3DVar and EnKF algorithms are used to assimilate AMsU-A radiance data. Results show that both variational and EnKF-based bias correction procedures effectively reduce the observation and background radiance differences, achieving positive impacts on forecasts. With proper bias correction, we assimilate full radiance observations including AMsU-A, AMsU-B, AIRs, HIRs3/4, and MHs in the second group. The relative percentage improvements (RPIs) for all forecast variables compared to those without radiance data assimilation are mostly positive, with the RPI of upper-air relative humidity being the largest. Additionally, precipitation forecasts on a downscaled 13-km grid from 40-km EnKF analyses are also improved by radiance assimilation for almost all forecast hours.

关键词： satellite radiance assimilation EnKF bias correction

special Topic： Cretaceous greenhouse palaeoclimate and sea-level changes

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science China Earth sciences 2017年第1期60卷 1-4页

作者： XiuMian HU Michael WAGREICH benjamin sAMEs state Key Laboratory of Mineral Deposits Research School of Earth Sciences and Engineering Nanjing University China Department of Geodynamics and sedimentology Center for Earth Sciences University of Vienna Austria

Earth＇s climate has oscillated between greenhouse （warm） and icehouse （cold） modes throughout Earth history. At present, Earth is in the midst of an icehouse climate interval, despite the anthropogenic contribution to global warming and sea-level rise due to industrialization during the past two centuries. This led to a dramatic increase in atmospheric CO2, mainly caused by the extensive burning of fossils fuels. The Cretaceous （145 to 66 million years ago） is the youngest prolonged greenhouse climate interval in the Phanerozoic, marked by very high global mean temperatures with some extreme warming peaks （＇hothouse＇ or ＇supergreenhouse＇）, largely absence of permanent continental ice sheets, a mean global sea-level having been some 250 m higher than that of today, and levels of carbon dioxide 4 to 10 times higher than those of the pre-industrial era. If temperature will continue to rise as quickly as in the last three decades, we are close to being at the cusp to a new greenhouse climate interval facing quickly rising global sea-level and reaching atmospheric CO2 levels of the ＇Cretaceous supergreenhouse＇ in about the years 2190-2260 （Hay, 2011）. Evidence from Earth＇s history indicates that glacial-interglacial climate mode changes as well as past sea-level changes such as in the Cretaceous greenhouse occurred at rates orders of magnitude slower than observed at present. The recent rise in global sea-level in response to rising levels of atmospheric greenhouse gases, the associated global warm- ing, and the waning of continental ice shields is a primary concern for human society. To predict future sea-levels we need a better understanding of the record of past sea-level changes, especially in the greenhouse palaeoclimate modes. Therefore, understanding the Cretaceous palaeoclimate is essential for a more accurate prediction of future global climate, sea-level rise and environmental changes in a prospective ＇Cretaceous-like＇ greenhouse Earth.

关键词： greenhouse Cretaceous warming anthropogenic despite throughout

A new rat model of portal hypertension induced by intraportal injection of microspheres

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World Journal of Gastroenterology 1998年第1期4卷 71-74页

作者： LI Xiang-Nong Is benjamin B Alexander Department of Liver surgery Affiliated Hospital Xuzhou Medical College Xuzhou 221002 China Department of surgery King's Coll. Sch. of Med. and Dent. London United Kingdom Department of Liver surgery Affiliated Hospital Xuzhou Medical College China Xuzhou Medical College China Beijing Medical University China Department of surgery King's College School and Dentistry United Kingdom Department of Liver surgery Affiliated Hospital Xuzhou Medical College Xuzhou 221002 50 Jiaheqian Street China

IM To produce a new rat model of portal hypertension by intraportal injection of microspheres.METHODs Measured aliquots of single or differentsized microspheres (15, 40, 80μm) were injected into the portal vein to block intrahepatic portal radicals. The resultant changes in arterial, portal, hepatic venous and splenic pulp pressures were monitored. The liver and lungs were excised for histological examination.REsULTs Portal venous pressure was elevated from basal value of 089-102 kPa to a steadystate of 198-319 kPa following the sequential injections of single or differentsized microspheres, with a markedly lowered mean arterial pressure. However, a smalldose injection of 80μm microspheres (18×105) produced a steadystate portal venous pressure of 253±017 kPa, and all rats showed normal arterial pressures. In addition, numerous microspheres were found in the lungs in all experimental groups.CONCLUsION Portal hypertension can be reproduced in rats by intraportal injection of microspheres at a small dose of 80μm (18×105). Intrahepatic portalsystemic shunts probably exist in the normal rat liver..

关键词： portal vein hypertension,portal disease model,animal latex microsphere

Giant mid-IR resonant coupling to molecular vibrations in sub-nm gaps of plasmonic multilayer metafilms

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Light(science & Applications) 2022年第10期11卷 2476-2484页

作者： Rakesh Arul David-benjamin Grys Rohit Chikkaraddy Niclas s.Mueller Angelos Xomalis Ermanno Miele Tijmen Geuser Jeremy J.Baumberg NanoPhotonics Centre Cavendish LaboratoryDepartment of PhysicsJJ Thompson AvenueUniversity of CambridgeCambridge CB30HEUnited Kingdom The Faraday Institution Quad OneHarwell Science and Innovation CampusDidcotUnited Kingdom

Nanomaterials capable of confining light are desirable for enhancing spectroscopies such as Raman scattering,infrared absorption,and nonlinear optical *** superlattices have shown the ability to host collective resonances in the mid-infrared,but require stringent fabrication processes to create well-ordered ***,we demonstrate how short-range-ordered Au nanoparticle multilayers on a mirror,self-assembled by a sub-nm molecular spacer,support collective plasmon-polariton resonances in the visible and infrared,continuously tunable beyond 11 pm by simply varying the nanoparticle size and number of *** resulting molecule-plasmon system approaches vibrational strong coupling,and displays giant Fano dip strengths,sEIRA enhancement factors~106,light-matter coupling strengths g~100 cm-1,Purcell factors~106,and mode volume compression factors~*** collectiive plasmon-polariton mode is highly robust to nanoparticle vacancy disorder and is sustained by the consistent gap size defined by the molecular *** disorder efficiently couples light into the gaps between the multilayers and mirror,enabling Raman and infrared sensing of sub-picolitre sample volumes.

关键词： coupling collective mirror

Reconstructing ancestral ranges in historical biogeography:properties and prospects

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Journal of systematics and Evolution 2009年第5期47卷 369-382页

作者： Kristin s.LAMM benjamin D.REDELINGs Bioinformatics Research Center North Carolina State University

Recent years have witnessed a proliferation of quantitative methods for biogeographic *** particular,novel parametric approaches represent exciting new opportunities for the study of range ***,we review a selection of current methods for biogeographic analysis and discuss their respective *** methods include generalized parsimony approaches,weighted ancestral area analysis,dispersal-vicariance analysis,the dispersal-extinction-cladogenesis model and other maximum likelihood approaches,and Bayesian stochastic mapping of ancestral ranges,including a novel approach to inferring range evolution in the context of island *** of these methods were developed specifically for problems of ancestral range reconstruction,whereas others were designed for more general problems of character state reconstruction and subsequently applied to the study of ancestral *** for reconstructing ancestral history on a phylogenetic tree differ not only in the types of ancestral range states that are allowed,but also in the various historical events that may change the ancestral *** explore how the form of allowed ancestral ranges and allowed transitions can both affect the outcome of ancestral range ***,we mention some promising avenues for future work in the development of model-based approaches to biogeographic analysis.

关键词： allopatry ancestral range ancestral state reconstruction biogeography dispersal historical biogeogra-phy review speciation statistics vicariance.

The Civil Examination system in Late Imperial China, 1400-1900

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Frontiers of History in China 2013年第1期8卷 32-50页

作者： benjamin A, Elman Department Princeton University Princeton NJ 08544-1008 USA

scholars often contend that civil examinations were what made imperial China a political meritocracy. They point to the examination system to show that the selection process served more as a common training program for literati than as a gate-keeper to keep non-elites out. Despite the symbiotic relations between the court and its literati, the emperor played the final card in the selection process. The asymmetrical relations between the throne and its elites nevertheless empowered elites to seek upward mobility as scholar-officials through the system. But true social mobility, peasants becoming officials, was never the goal of state policy in late imperial China; a modest level of social circulation was an unexpected consequence of the meritocratic civil service. Moreover, the meri^t-based bureaucracy never broke free of its dependence on an authoritarian imperial system. A modem political system might be more compatible with meritocracy, however. One of the unintended consequences of the civil examinations was creation of classically literate men （and women）, who used their linguistic talents for a variety of non-official purposes, from literati physicians to local pettifoggers, from fiction-writers to examination essay teachers, from Buddhist and Daoist monks to mothers and daughters. If there was much social mobility, i.e., the opportunity for members of the lower classes to rise in the social hierarchy, it was likely here. Rather than ＂social mobility,＂ this phenomenon might be better described as a healthy ＂circulation＂ of lower and upper elites when compared to aristocratic Europe and Japan.

关键词： Meritocracy civil service examinations late imperial China education reproduction

Test Elements, Generic Elements and Almost Primitivity in Free Products

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Algebra Colloquium 2016年第2期23卷 263-280页

作者： Ann-Kristin Engel benjamin Fine Gerhard Rosenberger Faculty of Mathematics TU-Braunschweig 38106 Braunschweig Germany Department of Mathematics Fairfield University Fairfield Connecticut 06430 USA Fachbereich Mathematik University of Hamburg Bundesstrasse 55 20146 Hamburg Germany FIM University of Passau Innstrasse 33 94032 Passau Germany

In [5, 6] the relationships between test words, generic elements, almost primitivity and tame almost primitivity were examined in free groups. In this paper we extend the concepts and connections to general free produ... 详细信息

关键词： test elements generic elements almost primitive elements free products

Nanoparticle assembly enabled by EHD-printed monolayers

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Microsystems & Nanoengineering 2017年第1期3卷 154-162页

作者： benjamin Francis Porter Nhlakanipho Mkhize Harish Bhaskaran Department of Materials University of OxfordOxford OX13PHUK

Augmenting existing devices and structures at the nanoscale with unique functionalities is an exciting *** is the ability to eventually enable at the nanoscale,a version of rapid prototyping via additive *** this requires a step-up in manufacturing for industrial use of these devices through fast,inexpensive prototyping with nanoscale *** this paper,we combine two very promising techniques—self-assembly and printing—to achieve additively nanomanufactured *** start by showing that monolayers can drive the assembly of nanoparticles into pre-defined patterns with single-particle resolution;then crucially we demonstrate for the first time that molecular monolayers can be printed using electrohydrodynamic(EHD)-jet *** functionality and resolution of such printed monolayers then drives the self-assembly of nanoparticles,demonstrating the integration of EHD with *** shows that such process combinations can lead towards more integrated process flows in ***,in-process metrology is a key requirement for any large-scale nanomanufacturing,and we show that Dual-Harmonic Kelvin Probe Microscopy provides a robust metrology technique to characterising these patterned structures through the convolution of geometrical and environmental *** represent a first step toward combining different additive nanomanufacturing techniques and metrology techniques that could in future provide additively nanomanufactured devices and structures.

关键词： additive nanomanufacturing dual-harmonic Kelvin probe microscopy electrohydrodynamic printing self-assembly 24 nanoparticles

The OpenstreetMap folksonomy and its evolution

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Geo-spatial Information science 2017年第3期20卷 219-230页

作者： Franz-benjamin Mocnik Alexander Zipf Martin Raifer Institute of Geography Heidelberg UniversityHeidelbergGermany

The comprehension of folksonomies is of high importance when making sense of Volunteered Geographic Information(VGI),in particular in the case of OpenstreetMap(OsM).so far,only little research has been conducted to understand the role and the evolution of folksonomies in VGI and OsM,which is despite the fact that without a comprehension of the folksonomies the thematic dimension of data can hardly be *** article examines the history of the OsM folksonomy,with the aim to predict its future *** particular,we explore how the documentation of the OsM folksonomy relates to its actual use in the data,and we investigate the historical and future scope and granularity of the ***,a visualization technique is proposed to examine the folksonomy in more detail.

关键词： Volunteered Geographic Information(VGI) OpenstreetMap(OsM) folksonomy taxonomy evolution granularity visualization