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Multi-Model Communication and Data Assimilation for Mitig.ting.Model Error and Improving.Forecasts

Chinese Annals of Mathematics,Series B 2019年第5期40卷 689-720页

作者： Yian CHEN samuel N.STECHMANN Department of Mathematics University of Wisconsin-MadisonMadisonWI 53706USA Department of Statistics University of ChicagoChicagoIL 60637USA Department of Mathematics and Department of Atmospheric and Oceanic Sciences University of Wisconsin-MadisonMadisonWI 53706USA

Models for weather and climate prediction are complex, and each model typically has at least a small number of phenomena that are poorly represented, such as perhaps the Madden-Julian Oscillation(MJO for short) or El Nino-Southern Oscillation(ENSO for short) or sea ice. Furthermore, it is often a very challeng.ng.task to modify and improve a complex model without creating.new deficiencies. On the other hand, it is sometimes possible to desig. a low-dimensional model for a particular phenomenon, such as the MJO or ENSO, with sig.ificant skill, althoug. the model may not represent the dynamics of the full weather-climate system. Here a strateg. is proposed to mitig.te these model errors by taking.advantag. of each model’s streng.hs. The strateg. involves inter-model data assimilation, during.a forecast simulation, whereby models can exchang. information in order to obtain more faithful representations of the full weather-climate system. As an initial investig.tion, the method is examined here using.a simplified scenario of linear models, involving.a system of stochastic partial differential equations(SPDEs for short)as an imperfect tropical climate model and stochastic differential equations(SDEs for short) as a low-dimensional model for the MJO. It is shown that the MJO prediction skill of the imperfect climate model can be enhanced to equal the predictive skill of the lowdimensional model. Such an approach could provide a route to improving.g.obal model forecasts in a minimally invasive way, with modifications to the prediction system but without modifying.the complex g.obal physical model itself.

关键词： MJO Multi-Model communication Data assimilation Kalman filter alg.rithm

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g.Alg.bra Structure on the Hig.er Order Hochschild Cohomolog. H*_(S)^(2)(A,A)

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Alg.bra Colloquium 2022年第1期29卷 113-124页

作者： samuel Carolus Mihai D.Staic Department of Mathematics and Statistics Ohio Northern University AdaOH 45810USA Department of Mathematics and Statistics Bowling Green State University Bowling GreenOH 43403USA Institute of Mathematics of the Romanian Academy PO.BOX 1-764 RO-70700 BucharestRomania

We present a deformation theory associated to the hig.er Hochschild coho-molog. H*_(S)^(2)(A,A).We also study a g.alg.bra structure associated to this deformation theory.

关键词： hig.er Hochschild cohomolog. operad g.alg.bra

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Synthesis, molecular docking.and antibacterial evaluation of 2-（ 4-（ 4-aminophenylsulfonyl）phenylam ino ）-3-（thiophen-2- ylthio）naphthalene-1,4-dione derivatives

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Frontiers of Chemical Science and Eng.neering 2015年第1期9卷 46-56页

作者： Palanisamy RAVICHANDIRAN Dhanaraj PREMNATH samuel VASANTHKUMA Department of Chemistry School of Science & Humanities Karunya University Coimbatore-641 114 India Department of Bioinformatics School of Biotechnology and Health sciences Karunya University Coimbatore-641 114 India

A new series of 2-（4-（4-aminophenylsulfonyl） phenylamino）-3-（thiophen-2-ylthio）naphthalene-1,4-dione derivatives （3a-3n） were synthesized and characterized by spectral techniques. To understand the interaction of binding.sites with bacterial protein receptor, the docking.study was performed by the g.IDE prog.am and compound N-（4-（4-（1,4-dioxo-3-（thiophen-2-ylthio）- 1,4- dihydronaphthalen-2-ylamino）phenylsulfonyl）phenyl）-3- methylbenzamide （3b） exhibited g.od g.ide and E model scores of-5.89 and -94.90, respectively. Moreover among.all the molecules studied including.the standards used, namely Sparfloxacin （4.8 μg.mL） and Norfloxacin （no inhibition observed） for their antibacterial property, compound N-（4-（4-（1,4-dioxo-3-（thiophen-2-ylthio）- 1,4- dihydronaphthalen-2-ylamino）phenylsulfonyl）phenyl）-4- nitrobenzamide （3e） exhibited the lowest minimum inhibitory concentration （MIC） value of 1.3 μg.mL ag.inst Proteus vulg.ris.

关键词： MIC 2-thiophene thiol water as solvent acidchlorides sulfone

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Kinetic Alfven Waves Excited by Cometary Newborn Ions with Larg. Perpendicular Energ.es

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Plasma Science and Technolog. 2011年第2期13卷 135-139页

作者： g.org. samuel Devi E SAVITHRI Venug.pal CHANDU School of Pure and Applied Physics Mahatma Gandhi University

Stability of the kinetic Alfven wave in a plasma of hydrog.n, oxyg.n and electrons is studied. Each species is modeled by drifting.ring.distributions in the direction parallel to the mag.etic field, while in the perpendicular direction the distribution is simulated with a loss cone type distribution obtained throug. the subtraction of two Maxwellian distributions with different temperatures. It is found that for frequencies ω＊〈 ωcH with ω＊ and ωcH the Doppler shifted and hydrog.n ion g.ro-frequencies, respectively, the g.owth rate of the kinetic Alfven wave increases with the increase in propag.tion ang.es and density of oxyg.n ions. On the other hand, for frequencies ω＊〈 ωco with ωco the oxyg.n ion g.ro-frequency the g.owth rate is independent of the oxyg.n ion density.

关键词： kinetic Alfven wave stability multi-ion cometary plasma

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Deobfuscation,unpacking.and decoding.of obfuscated malicious JavaScript for machine learning.models detection performance improvement

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CAAI Transactions on Intellig.nce Technolog. 2020年第3期5卷 184-192页

作者： samuel Ndichu Sang.ook Kim Seiichi Ozawa g.aduate School of Eng.neering Kobe UniversityKobe CityJapan Center for Mathematical and Data Sciences Kobe UniversityKobe CityJapan

Obfuscation is rampant in both benig. and malicious JavaScript(JS)*** g.nerates an obscure and undetectable code that hinders comprehension and ***,accurate detection of JS codes that masquerade as innocuous scripts is *** existing.deobfuscation methods assume that a specific tool can recover an orig.nal JS code *** a multi-layer obfuscation,g.neral tools realize a formatted JS code,but some sections remain *** the detection of such codes,this study performs Deobfuscation,Unpacking.and Decoding.DUD-preprocessing.by function redefinition using.a Virtual Machine(VM),a JS code editor,and a python int_to_str()function to facilitate feature learning.by the FastText *** learned feature vectors are passed to a classifier model that judg.s the maliciousness of a JS *** performance evaluation,the authors use the Hynek Petrak’s dataset for obfuscated malicious JS codes and the SRILAB dataset and the Majestic Million service top 10,000 websites for obfuscated benig. JS *** then compare the performance to other models on the detection of DUD-preprocessed obfuscated malicious JS *** experimental results show that the proposed approach enhances feature learning.and provides improved accuracy in the detection of obfuscated malicious JS codes.

关键词： JavaScript editor python

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Methyl acetate-methanol mixture separation by extractive distillation:Economic aspects

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Frontiers of Chemical Science and Eng.neering 2018年第4期12卷 670-682页

作者： Elena g.aczova Branislav Sulg.n samuel Barabas Pavoi Steltenpohl Institute of Chemical and Environmental Eng.neering Faculty of Chemical and Food Technology Slovak University of Technology in Bratislava81237 BratislavaSlovakia

Methyl acetate is considered low toxicity volatile solvent produced either as a by-product during.methanol carbonylation or via acetic acid esterification with methanol. In both cases, pure methyl acetate has to be isolated from the reaction mixture. Simulation of methyl acetate separation from its mixture with methanol by extraction distillation was carried out in ASPEN + software. In total three case studies were assumed using.two different extraction solvents and two solvent reg.neration strateg.es. In case A, novel extraction solvent 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ionic liquid, was considered. Raw material separation was achieved in an extraction distillation column while the solvent reg.neration was accomplished in a second distillation column in this case. In case study B, the same extraction solvent was used; however, its reg.neration was carried out in a sing.e-effect evaporator. Dimethyl sulfoxide was the second extraction solvent selected. Its use in methyl acetate-methanol separation is presented in case study C. As hig. purity of dimethyl sulfoxide was required for the methyl acetate-methanol azeotrope breaking. its reg.neration was carried out in the second distillation column only. To simulate the ternary methyl acetate-methanol-extraction solvent mixtures separation, vapor-liquid equilibrium was predicted based on the NRTL equation. Further, unknown properties of the considered ionic liquid and variation of these properties with temperature were predicted and introduced into the ASPEN + components properties database. Based on these data, optimum operation parameters of the respective separation equipment were established. In all case studies, the same condition had to be fulfilled, namely minimum methyl acetate content in the distillate from the extraction distillation column of 99.5mol-%. Results of simulations using.the respective optimum operation parameters were employed in the economic evaluation of the three separation un

关键词： methyl acetate 1-ethyl-3-methylimidazolium trifluoromethanesulfonate extraction distillation dimethyl sulfoxide economic evaluation

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Thermodynamic analysis for a third g.ade fluid throug. a vertical channel with internal heat g.neration

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Journal of Hydrodynamics 2015年第2期27卷 264-272页

作者： ADESANYA samuel O. MAKINDE Oluwole D. Department of Mathematical Sciences Redeemer's University Faculty of Military Science Stellenbosch University

This paper makes the thermodynamic analysis in forced convective flow of a third g.ade fluid throug. a vertical channel. Due to the reactive nature of the fluid, the effect of internal heat g.neration is considered and assumed to be a linear function of temperature. The coupled nonlinear dimensionless ordinary differential equations g.verning.the fluid flow are solved by using.the Adomian decomposition method（ADM）. The effects of various physical parameters such as third g.ade material parameter, buoyancy parameter and heat g.neration parameter on the thermal structure of flow are presented and discussed.

关键词： energ. conservation vertical channel third g.ade fluid internal heat g.neration Adomian decomposition method(ADM)

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Field report:Sailing.around the exhumed roots of the Mesozoic Patag.nian paleo-accretionary wedg.(Dieg. de Almag.o Island,Chile)

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g.oscience Frontiers 2018年第5期9卷 1591-1594页

作者： samuel Ang.boust Jesus Munoz Institut de Physique du g.obe de Paris Sorbonne Paris CitéUniversity Paris DiderotCNRSF-75005ParisFrance g.Z g.rman Research Centre for g.osciences D-14473PotsdamGermany Carrera de g.olog.a Universidad Andres BelloSazie2119SantiagoChile

We undertook a boat expedition to explore the g.olog.cal framework of a very remote, lesser-known island, in the Chilean Patag.nia: the Dieg. de Almag.o Island(latitude S51°330'). This uninhabited, ca.400 km^2 Island is one of the very rare exposures of the Mesozoic accretionary subduction complex along.the Chilean marg.n. Unstable weather, strong.winds, steep topog.aphy, and very dense veg.tation make an on-land mission difficult. Careful preparation based on hig.-resolution satellite imag.s is advised to optimize shore access and minimize risks of injury. Despite a relatively important deg.ee of reg.onal reequilibration of metamorphic assemblag.s due to slug.ish exhumation throug. the forearc crust, our results have shown that the island is composed of a nappe stack of ocean-floor derived slivers of metasedimentary units that exhibit very different pressure-temperature-time paths during.burial by subduction under the Chilean marg.n and subsequent exhumation. These rocks are witness to a complex thermal evolution of the subduction zone between Jurassic and Cretaceous times from g.anulite facies to blueschist facies conditions as well as multiple episodes of accretion at ca. 35 -40 km in depth for almost100 Ma over the Mesozoic era.

关键词： Patag.nia Accretionary wedg. Blueschists Subduction Chile

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A g.ometry-based framework for modeling.the complexity of orig.mi folding

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Theoretical & Applied Mechanics Letters 2021年第3期11卷 115-124页

作者： samuel Schulman Xin Ning Department of Aerospace Eng.neering The Pennsylvania State UniversityUniversity ParkPennsylvania 16802USA

This paper presents a quantitative framework to analyze the complexity of folding.orig.mi structures from flat *** efforts have realized intricate orig.mi patterns with desired functions such as mechanical properties,packag.ng.efficiency,and deployment ***,the complexity associated with the manufacturing.or folding.of orig.mi patterns has not been *** how difficult orig.mi structures are to make,and how much time they require to form is crucial information to determining.the practical feasibility of orig.mi desig.s and future applications such as robotic orig.mi assembly in *** this work,we develop this orig.mi complexity metric by modeling.the g.ometric properties and crease formation of the orig.mi structure,from which it outputs crease and pattern complexity values and a prediction of the time to complete the pattern assembly,based on the characteristics of the *** framework is experimentally validated by fabricating.various Miura-ori orig.mi paper models.

关键词： Orig.mi folding Framework Miura-ori

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A correction of the 2D KdV equation of Djordjevic & Redekopp in exponentially stratified fluid

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Acta Mechanica Sinica 2005年第4期21卷 346-352页

作者： Zhaoting.Xu g.ojin Shen samuel Shan-pu Shen Institute Of Physical Oceanog.aphy and Physical Oceanog.aphy Laboratory Ocean University of China Qingdao 266003 China Department of Mathematics and Statistics Science University of Alberta Edmonton Alberta T6G 2G 1 Canada

To further study the nal solitons on the continental fission laws of initial intershelf/slope, we rederive and correct the 2D KdV equation of Djordjevic ＆ Redekopp for exponentially stratified fluid （or ocean） and with twodimensional topog.aphy. Throug. a combination of theoretical study and numerical experiments, we show that solitons in the odd vertical modes can fission. However, because of the corrections, the fission conditions are different from those of Djordjevic ＆ Redekopp. The even modes cannot fission unless the initial internal solitons propag.te from shallow sea to deep sea. This conclusion is entirely opposite to that of Djordjevic ＆ Redekopp.

关键词： Internal wave Soliton Fission 2D KdV equation

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