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针对热带飓风的风场、波浪和风暴潮的NOPP实时预报系统

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人民珠江 2006年第6期27卷 4-9页

作者： Scott C.HAGeN Hans C.GRABeR Vincent J.CARDONe Andrew T.COX robert e.jensen Donald N.SLINN Mark D.POWeLL 耿兵绪中佛罗里达州大学迈阿密大学海洋气象公司美国陆军工程兵团佛罗里达州大学美国国家海洋大气局大西洋海洋气象实验室飓风研究所

介绍针对热带气旋的风场、波浪、风暴潮的NOPP(国家海洋合作项目)实时预报系统。这个系统的低分辨率模式曾被用于2004年和2005年的飓风季节预测,国家飓风中心每6 h在内部网上发布飓风路径、极限半径与特征浪高的预测值。这个预测系统通... 详细信息

介绍针对热带气旋的风场、波浪、风暴潮的NOPP(国家海洋合作项目)实时预报系统。这个系统的低分辨率模式曾被用于2004年和2005年的飓风季节预测,国家飓风中心每6 h在内部网上发布飓风路径、极限半径与特征浪高的预测值。这个预测系统通过输入来自H*WIND的高精度初始风场数据来预测以后每半小时的风场预测数据。改进后的风场数据被用于追踪飓风路径以及驱动三阶的波浪模块和风暴潮模块。而波浪模块得出的辐射压力场则被耦合于飓风登陆时的海岸风暴潮位预测中。此系统正在采用低分辨率与高分辨率模式模拟2006年飓风季节情况。

关键词：实时预测波浪模拟潮汐模拟风暴潮模拟热带气旋飓风

High Impact Polylactide Based on Organosilicon Nucleation Agent

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Chinese Journal of Polymer Science 2024年第6期42卷 787-797页

作者： Daria Pakuła Bogna Sztorch eliza Romańczuk-Ruszuk Bogdan Marciniec robert e.Przekop Faculty of Chemistry Adam Mickiewicz University in PoznańUniwersytetu Poznańskiego 861-614PoznańPoland Centre for Advanced Technologies Adam Mickiewicz University in PoznańUniwersytetu Poznańskiego 1061-614PoznańPoland Institute of Biomedical engineering Faculty of Mechanical EngineeringBialystok University of TechnologyWiejska 45C15-351BialystokPoland

Various sectors of the industry are searching for new materials with specific requirements,providing improved *** study presents novel composite materials based on polylactide that have been modified with the organosilicon compound,(3-thiopropyl)polysilsesquioxane(SSQ-SH).The SSQ-SH compound is a mixture of cage structures and not fully condensed random *** composite materials were obtained through injection *** study includes a comprehensive characterization of the new materials that analyze their functional properties,such as rheology(MFR),mechanical strength(tensile strength,Charpy impact strength),and thermal *** microscopic photos were also taken to analyze the microstructure of the *** addition of a 5%by-weight organosilicon compound to polylactide resulted in a significant increase in MFR by 73.8%compared to the neat *** greatest improvement in impact strength was achieved for the 5%SSQ-SH/PLA composite,increasing it by 32.0 kJ/m^(2)compared to PLA,which represents an increase of up to 187%.The conducted research confirms the possibility of modifying the properties of the polymer by employing organosilicon compounds.

关键词： Octa(3-thiopropyl)silsesquioxane 8SH-POSS Polylactide(PLA) Injection moulding Composites

Predicting the coefficient of friction in a sliding contact by applying machine learning to acoustic emission data

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Friction 2024年第6期12卷 1299-1321页

作者： robert GUTIeRReZ Tianshi FANG robert MAINWARING Tom ReDDYHOFF Tribology Group Department of Mechanical EngineeringImperial College LondonExhibition RoadLondon SW72AZUK Shell Global Solutions(US)Inc.Shell Technology Center Houston 3333 Highway 6 SouthHoustonTX 77082USA Shell International Petroleum Company Limited Shell CentreYork RoadLondon SE17NAUK

It is increasingly important to monitor sliding interfaces within machines,since this is where both energy is lost,and failures *** emission(Ae)techniques offer a way to monitor contacts remotely without requiring transparent or electrically conductive ***,acoustic data from sliding contacts is notoriously complex and difficult to ***,we simultaneously measure coefficient of friction(with a conventional force transducer)and acoustic emission(with a piezoelectric sensor and high acquisition rate digitizer)produced by a steel‒steel rubbing *** data is then used to train machine learning(ML)algorithms(e.g.,Gaussian process regression(GPR)and support vector machine(SVM))to correlated acoustic emission with *** training requires the dense Ae data to first be reduced in size and a range of processing techniques are assessed for this(e.g.,down-sampling,averaging,fast Fourier transforms(FFTs),histograms).Next,fresh,unseen Ae data is given to the trained model and the resulting friction predictions are compared with the directly measured *** is excellent agreement between the measured and predicted friction when the GPR model is used on Ae histogram data,with root mean square(RMS)errors as low as 0.03 and Pearson correlation coefficients reaching ***,predictions remain accurate despite changes in test conditions such as normal load,reciprocating frequency,and stroke *** paves the way for remote,acoustic measurements of friction in inaccessible locations within machinery to increase mechanical efficiency and avoid costly failure/needless maintenance.

关键词： acoustic emission condition monitoring friction machine learning Gaussian process regression support vector machine

A general mirror equivalence theorem for coset vertex operator algebras

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Science China Mathematics 2024年第10期67卷 2237-2282页

作者： robert McRae Yau Mathematical Sciences Center Tsinghua UniversityBeijing 100084China

We prove a general mirror duality theorem for a subalgebra U of a simple conformal vertex algebra A and its commutant V=ComA(U).Specifically,we assume that A≌■_(i∈I)U_(i)■V_(i) as a U■V-module,where the U-modules Uiare simple and distinct and are objects of a semisimple braided ribbon category of Umodules,and the V-modules Viare semisimple and contained in a(not necessarily rigid) braided tensor category of *** also assume U=ComA(V).Under these conditions,we construct a braid-reversed tensor equivalence τ:u_(A)→v_(A),where u_(A)is the semisimple category of U-modules with simple objects Ui,i∈I,and v_(A)is the category of V-modules whose objects are finite direct sums of *** particular,the V-modules Viare simple and distinct,and v_(A)is a rigid tensor *** an application,we find a rigid semisimple tensor subcategory of modules for the Virasoro algebra at central charge 13+6p+6p^(-1),p∈Z_(≥2), which is braided tensor equivalent to an abelian 3-cocycle twist of the category of finite-dimensional ***,the Virasoro vertex operator algebra at central charge 13+6p+6p^(-1)is the PSL_(2)(C)-fixed-point subalgebra of a simple conformal vertex algebra w(-p),analogous to the realization of the Virasoro vertex operator algebra at central charge 13-6p-6p^(-1)as the PSL_(2)(C)-fixed-point subalgebra of the triplet algebra W(p).

关键词： vertex operator algebras coset conformal eld theory braid-reversed tensor equivalence Virasoro algebra

Necrotic enteritis and antibiotic-free production of broiler chickens:Challenges in testing and using alternative products

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Animal Nutrition 2024年第1期16卷 288-298页

作者： robert J.Moore School of Science RMIT University

The global trend towards raising broiler chickens without the use of in-feed antibiotics(IFAs) means that there is an ongoing need to develop alternative treatments capable of delivering the benefits that IFAs previously provided. IFAs supported the productivity performance of chickens and played a key role in maintaining their health. Necrotic enteritis(Ne) is an important disease of broilers that affects health,productivity, and welfare, and was previously well controlled by IFAs. However, with the reduction in IFA use, Ne is resurgent in some countries. Vaccines and various feed additives, including pre-, pro-, and postbiotics, phytobiotics, fatty acids, and phage therapies have been introduced as alternative methods of Ne control. While some of these feed additives have specific activity against the Ne pathogen, Clostridium perfringens, most have the more general goal of reinforcing gut health. extensive reviews of the effects of many of these feed additives on gut health have been published recently. Hence, rather than cover previously well reviewed areas of research this review focuses on the challenges and pitfalls in undertaking experimental assessment of alternative Ne treatments and translating laboratory research to real world commercial production settings. The review is based on the author's particular experience,reading, thoughts, and analysis of the available information and inevitably presents a particular understanding that is likely to be at odds with others thinking on these issues. It is put forward to stimulate thinking and discussion on the issues covered.

关键词： Necrotic enteritis Clostridium perfringens Vaccines Feed additive Farm management

Deterministic epidemic models overestimate the basic reproduction number of observed outbreaks

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Infectious Disease Modelling 2024年第3期9卷 680-688页

作者： Wajid Ali Christopher e.Overton robert R.Wilkinson Kieran J.Sharkey Department of Mathematical Sciences University of LiverpoolPeach StreetLiverpoolL697ZXEnglandUnited Kingdom Department of Applied Mathematics Liverpool John Moores UniversityByrom StreetLiverpoolL35UXEnglandUnited Kingdom

The basic reproduction number,R_(0),is a well-known quantifier of epidemic ***,a class of existing methods for estimating R_(0)from incidence data early in the epidemic can lead to an over-estimation of this *** particular,when fitting deterministic models to estimate the rate of spread,we do not account for the stochastic nature of epidemics and that,given the same system,some outbreaks may lead to epidemics and some may ***,an observed epidemic that we wish to control is a major *** amounts to implicit selection for major outbreaks which leads to the over-estimation *** formally characterised the split between major and minor outbreaks by using Otsu's method which provides us with a working *** show that by conditioning a‘deterministic’model on major outbreaks,we can more reliably estimate the basic reproduction number from an observed epidemic trajectory.

关键词： estimating R_(0) Simple birth-death process Major outbreak Conditioned epidemic Stochastic fade-out

A detailed rock density model of the Hong Kong territories

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Geodesy and Geodynamics 2024年第1期15卷 75-81页

作者： Albertini Nsiah Ababio robert Tenzer Department of Land Surveying and Geo-Informatics Hong Kong Polytechnic UniversityHong KongChina

We used the geological map and published rock density measurements to compile the digital rock density model for the Hong Kong *** then estimated the average density for the whole *** to our result,the rock density values in Hong Kong vary from 2101 to 2681 kg·m^(-3).These density values are typically smaller than the average density of 2670 kg·m^(-3),often adopted to represent the average density of the upper continental crust in physical geodesy and gravimetric geophysics *** finding reflects that the geological configuration in Hong Kong is mainly formed by light volcanic formations and lava flows with overlying sedimentary deposits at many locations,while the percentage of heavier metamorphic rocks is very low(less than 1%).This product will improve the accuracy of a detailed geoid model and orthometric heights.

关键词： Density model Rock types Gravimetric modeling Hong Kong

The concept of gene therapy for glaucoma:the dream that has not come true yet

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Neural Regeneration Research 2024年第1期19卷 92-99页

作者： robert Sulak Xiaonan Liu Adrian Smedowski Department of Physiology Faculty of Medical Sciences in KatowiceMedical University of Silesia in KatowiceKatowicePoland Institute of Biotechnology HiLIFEUniversity of HelsinkiHelsinkiFinland GlaucoTech Co. KatowicePoland

Gene therapies,despite of being a relatively new therapeutic approach,have a potential to become an important alternative to current treatment strategies in *** glaucoma is not considered a single gene disease,the identified goals of gene therapy would be rather to provide neuroprotection of retinal ganglion cells,especially,in intraocular-pressure-independent *** most commonly reported type of vector for gene delivery in glaucoma studies is adeno-associated virus serotype 2 that has a high tro pism to retinal ganglion cells,res ulting in long-term expression and low immunogenic *** gene thera py studies recruit inducible and genetic animal models of optic neuropathy,like DBA/2J mice model of high-tension glaucoma and the optic nerve *** gene therapy-based neuroprotection of retinal ganglion cells is targeting specific genes translating to growth factors(i.e.,brain derived neurotrophic factor,and its receptor TrkB),regulation of apoptosis and neurodegeneration(i.e.,Bcl-xl,Xiap,FAS system,nicotinamide mononucleotide adenylyl transferase 2,Digit3 and Sarm1),immunomodulation(i.e.,Crry,C3 complement),modulation of neuroinflammation(i.e.,e rythropoietin),reduction of excitotoxicity(i.e.,Com KIlα)and transcription regulation(i.e.,Max,Nrf2).On the other hand,some of gene therapy studies focus on lowering intra ocular pressure,by impacting genes involved in both,decreasing aqueous humor production(i.e.,aquaporin 1),and increasing outflow facility(i.e.,COX2,prostaglandin F2a receptor,RhoA/RhoA kinase signaling pathway,MMP1,Myocilin).The goal of this review is to summarize the current stateof-art and the direction of development of gene therapy strategies for glaucomatous neuropathy.

关键词： adeno-associated virus gene editing gene therapy glaucoma IOP lowering IOP-independent mechanisms neuroprotection optic nerve optic neuropathy retinal ganglion cells

Optimization of product characteristics of porous carbon agglomerates using a design of experiments in fluidized bed agglomeration

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Particuology 2024年第6期89卷 258-269页

作者： Martin Oelofse robert Rack Marcelle Hilden Peter Langguth Department of Pharmaceutical Technology and Biopharmaceutics Johannes Gutenberg UniversityMainzGermany Carbon Advanced Solutions GmbH HeuchelheimGermany

Spraying parameters during particle agglomeration processes can affect the agglomeration kinetics and particle *** study was conducted to better understand the influence of the spraying parameters in a fluidized bed wet agglomeration process,and the influence on the stability characteristics of carbon tablets.A formulation based on fine carbon and peroxide powder,as well as carboxymethyl cellulose as a binder,was used to produce agglomerates in a first production *** in a second production step carbon tablets with a high porosity were molded for the customer goods *** optimization of the compressive strength of these carbon tablets was the goal of the *** agglomerates were produced with a laboratory scale granulator called“ProCell”and were compressed with a five-cavity mechanical *** screening of the agglomeration process parameters and their influence on the agglomerates quality,as well as the performance characteristics of the carbon tablets,were investigated using a multilevel factorial *** experimental runs were done by varying atomized air pressure and feed rate of the *** was determined by the design *** findings of the statistical trials showed that low atomized air pressure and a low feed rate lead to a higher tablet compressive strength.

关键词： Wet agglomeration Fluidized bed Design of experiments Carbon agglomerates and tablets