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A Non-Parametric Scheme for Identifying Data Characteristic Based on Curve Similarity Matching

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1424-1437页

作者： Quanbo Ge Yang Cheng Hong li Ziyi Ye Yi Zhu gang Yao School of Automation Nanjing University of Information Science&TechnologyJiangsu Provincial University Key Laboratory of Big Data Analysis and Intelligent SystemsNanjing University of Information Science&Technologyand the Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology(CICAEET)Nanjing University of Information Science&TechnologyNanjing 210044China School of Department of Logistics Engineering Shanghai Maritime UniversityShanghai 201306China China Classification Society Nantong Office Nantong 226006China Chinese Flight Test Establishment Xi’an 710089China School of Mathematics Tsinghua UniversityBeijing 100084China School of Automation Nanjing University of Information Science&TechnologyNanjing 210044China Department of Logistics Engineering Shanghai Maritime UniversityShanghai 201306China IEEE

For accurately identifying the distribution charac-teristic of Gaussian-like noises in unmanned aerial vehicle(UAV)state estimation,this paper proposes a non-parametric scheme based on curve similarity *** the framework of the pro-posed scheme,a Parzen window(kernel density estimation,KDE)method on sliding window technology is applied for roughly esti-mating the sample probability density,a precise data probability density function(PDF)model is constructed with the least square method on K-fold cross validation,and the testing result based on evaluation method is obtained based on some data characteristic analyses of curve shape,abruptness and *** com-parison simulations with classical methods and UAV flight exper-iment shows that the proposed scheme has higher recognition accuracy than classical methods for some kinds of Gaussian-like data,which provides better reference for the design of Kalman filter(KF)in complex water environment.

关键词： Curve similarity matching Gaussian-like noise non-parametric scheme parzen window.

Facile molybdenum and aluminum recovery from spent hydrogenation catalyst

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Chinese Journal of Chemical Engineering 2024年第5期69卷 72-78页

作者： Zhenhui Lv Jianan li Dong Xue Tao Yang gang Wang Chong Peng State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024China Dalian Research Institute of Petroleum and Petrochemicals SINOPECDalian 116041China

Industrial catalyst waste has emerged as a hazardous pollutant that requires safe and proper disposal after the unloading *** a valuable and sustainable strategy for its treatment is a significant challenge compared to traditional *** this study,we present a facile method for the recovery of molybdenum and aluminum contents from spent Mo-Ni/Al_(2)O_(3) hydrogenation catalysts through crystallization separation and ***,the recovered molybdenum and aluminum are utilized as active metals and carriers for the preparation of new *** properties were thoroughly analyzed and investigated using various characterization *** hydrogenation activity of these newly prepared catalysts was evaluated on a fixed-bed small-scale device and compared with a reference catalyst synthesized from commercial raw ***,the hydrogenation activity of the catalysts was further assessed by using the entire distillate oil of coal liquefaction as the raw oil,specifically focusing on denitrogenation and aromatic *** work not only offers an effective solution for recycling catalysts but also promotes sustainable development.

关键词： Waste treatment Alumina Hydrogenation Catalyst Crystallization Precipitation

Characterization of physicochemical and immunogenic properties of allergenic proteins altered by food processing:a review

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Food Science and Human Wellness 2024年第3期13卷 1135-1151页

作者： Enning Zhou Qiangqiang li Dan Zhu gang Chen liming Wu Institute of Apicultural Research Chinese Academy of Agricultural SciencesBeijing 100093China Department of Food Science University of OtagoDunedin 9016New Zealand School of Food and Health Beijing Technology and Business UniversityBeijing 100048China

Food allergens are mainly naturally-occurring proteins with immunoglobulin E(IgE)-binding *** the structural and immunogenic characteristics of allergenic proteins is essential in assessing whether and how food processing techniques reduce *** here discuss the impacts of food processing technologies on the modification of physicochemical,structural,and immunogenic properties of allergenic *** techniques for characterizing changes in these properties of food allergens are *** processing helps to reduce allergenicity by aggregating or denaturing proteins,which masks,modifies,or destroys antigenic epitopes,whereas,it cannot eliminate allergenicity completely,and sometimes even improves allergenicity by exposing new ***,most food processing techniques have been tested on purified food allergens rather than food products due to potential interference of other food *** provide guidance for further development of processing operations that can decrease the allergenicity of allergenic food proteins without negatively impacting the nutritional profile.

关键词： Food allergens Protein structural characterization Immunogenicity evaluation Food processing modification

Revealing Al-O/Al-F reaction dynamic effects on the combustion of aluminum nanoparticles in oxygen/fluorine containing environments:A reactive molecular dynamics study meshing together experimental validation

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Defence Technology（防务技术） 2024年第4期34卷 313-327页

作者： gang li Chuande Zhao Qian Yu Fang Yang Jie Chen Institute of Chemical Materials China Academy of Engineering Physics(CAEP)P.O.Box 919-311Mianyang 621900SichuanChina

Improving the energy conversion efficiency in metallic fuel(e.g.,Al)combustion is always desirable but challenging,which often involves redox reactions of aluminum(Al)with various mixed oxidizing *** instance,Al-O reaction is the most common pathway to release limited energy while Al-F reaction has received much attentions to enhance Al combustion ***,microscopic understanding of the Al-O/Al-F reaction dynamics remains unsolved,which is fundamentally necessary to further improve Al combustion *** this work,for the first time,Al-O/Al-F reaction dynamic effects on the combustion of aluminum nanoparticles(n-Al)in oxygen/fluorine containing environments have been revealed via reactive molecular dynamics(RMD)simulations meshing together combustion *** RMD simulation systems of Al core/O_(2)/HF,n-Al/O_(2)/HF,and n-Al/O_(2)/CF4 with oxygen percentage ranging from 0%to 100%have been *** n-Al combustion in mixed O_(2)/CF_4 environments have been conducted by constant volume combustion *** results show that Al-O reaction exhibits kinetic benefits while Al-F reaction owns thermodynamic benefits for n-Al *** n-Al/O_(2)/HF,Al-O reaction gives faster energy release rate than Al-F reaction(1.1 times).The optimal energy release efficiency can be achieved with suitable oxygen percentage of 10%and 50%for n-Al/O_(2)/HF and n-Al/O_(2)/CF_4,*** combustion experiments,90%of oxygen percentage can optimally enhance the peak pressure,pressurization rate and combustion ***,Al-O reaction prefers to occur on the surface regions while Al-F reaction prefers to proceed in the interior regions of n-Al,confirming the kinetic/thermodynamic benefits of Al-O/Al-F *** synergistic effect of Al-O/Al-F reaction for greatly enhancing n-Al combustion efficiency is demonstrated at atomicscale,which is beneficial for optimizing the combustion performance of metallic fuel.

关键词： Al-O/Al—F reaction Kinetic benefits Thermodynamic benefits Molecular dynamics Combustion

Research on the flow stability and noise reduction characteristics of quasi-periodic elastic support skin

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Defence Technology（防务技术） 2024年第3期33卷 222-236页

作者： Lu Chen Shao-gang liu Dan Zhao li-qiang Dong Kai li Shuai Tang Jin Cui Hong Guo Department of Mechanical and Electrical Engineering Harbin Engineering UniversityHarbin150001China

To enhance flow stability and reduce hydrodynamic noise caused by fluctuating pressure,a quasiperiodic elastic support skin composed of flexible walls and elastic support elements is proposed for fluid noise *** arrangement of the elastic support element is determined by the equivalent periodic distance and quasi-periodic *** this paper,a dynamic model of skin in a fluid environment is *** influence of equivalent periodic distance and quasi-periodic coefficient on flow stability is *** results suggest that arranging the elastic support elements in accordance with the quasi-periodic law can effectively enhance flow ***,the hydrodynamic noise calculation results demonstrate that the skin exhibits excellent noise reduction performance,with reductions of 10 dB in the streamwise direction,11 dB in the spanwise direction,and 10 dB in the normal *** results also demonstrate that the stability analysis method can serve as a diagnostic tool for flow fields and guide the design of noise reduction structures.

关键词： Flow stability Quasi-period Flexible wall Elastic support element Hydrodynamic noise

Study of the blocking mechanism in gravel packing based on CFD-DEM

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Particuology 2024年第7期90卷 164-178页

作者： Fucheng Deng Lei Wen gang li Baitao Fan Ning Gong Shenghong Chen Yangtze University Jingzhou434023China Guangzhou Institute of Energy Conversion Chinese Academy of Sciences510640China CNOOC Research Institute Ltd Beijing100028China Tianjin Branch of CNOOC Ltd Tianjin300459China CNOOC Ener Tech-Drilling&Production Co Tianjin300457China

Gravel packing sand control(GPSC),as the optimization of mechanical sand control technology,is widely used in the deep water completion and sand control of loose sandstone heavy oil reservoirs and highly *** explore the blocking mechanism of GPSC,the influence of its structural parameters on the blocking of GPSC is *** paper establishes a particle element model based on computational fluid dynamics-discrete element method coupling using the discrete element method and establishes a fluid flow model combined with computational fluid dynamics to realize their full coupling *** sand control experiments were carried out using a micro visual sand control simulation device to verify the blocking *** blocking mechanism is analyzed from the microscopic point of view,and then,the influence of sand control structure parameters on the blocking in GPSC design is *** results show the following:(1)the blocking process of GPSC can be divided into three stages:an initial stage,sand accumulation stage,and equilibrium stage.(2)There are two main types of gravel packing *** first type of blocking is blocking on the surface of the gravel *** particles on the surface of gravel layer mainly exist in the form of large particle size blocking gravel pores and sand particles bridging each *** second type of blockage is the blockage inside the gravel *** particles mainly exist in the form of internal mud cakes and adsorption on gravels inside the gravel layer.(3)To ensure the sand control performance of the gravel layer,the gravel layer thickness is designed between 23 and 28 *** displacement or pressure of the on-site packing pump should be increased to ensure that the gravel layer packing solidity ranges between 59%and 62%.In the design of GPSC,it should be ensured that the median particle size of gravel is 5–6 times the median particle size of *** study provides an effective technical reference for the

关键词： CFD-DEM Blocking the process Blocking mechanism Structural parameter

Characteristics of Particulate Matter Emissions for Low-Sulfur Heavy Oil Used in Low-Speed Two-Stroke Diesel Engines of Ocean-Going Ships

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Journal of Thermal Science 2024年第2期33卷 739-750页

作者： WU gang MA Qianli WEI lijiang JIANG Guohe WANG Tengfei li Tie Merchant Marine College Shanghai Maritime UniversityShanghai201306China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai200240China

In this work,particulate matter(PM) emissions from a large two-stroke,low-speed marine diesel engine were investigated when the engine was operated with low-sulfur heavy fuel oil(HFO) at various *** samples were collected in situ from the engine exhaust to determine the detailed physical and chemical *** nanostructure and morphology of the nanoparticles were analyzed using transmission electron microscopy images(TEM).The results show that volatile organic carbon(OC) accounts for more than 80% in the HFO particles and leads to an increase in particle *** thermodynamic conditions of a low-speed engine favor the behavior of capturing the soluble organic components.A large number of spherical char HFO particles with aerodynamic diameters of 0.2 μm-0.5 μm and a suspected inner metal core were *** two peak aerodynamic diameters of the HFO nanoparticles are 15 nm and 86 *** morphological differences among the HFO nanoparticles in varied engine conditions represent the formation process from primary nascent particles to mature graphitized particles caused by *** above study will be valuable for understanding the characteristics of PM emissions from low-sulfur HFO to achieve the ship PM emissions reduction target.

关键词： low-speed diesel engine maritime regulations heavy fuel oil TEM particles size and distribution

Precession effects on a liquid planetary core

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Research in Astronomy and Astrophysics 2018年第2期18卷 115-124页

作者： Min liu li-gang li Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China University of Chinese Academy of Sciences Beijing 100049 China

Motivated by the desire to understand the rich dynamics of precessionally driven flow in a liquid planetary core, we investigate, through numerical simulations, the precessing fluid motion in a ro- taring cylindrical annulus, which simultaneously possesses slow precession. The same problem has been studied extensively in cylinders, where the precessing flow is characterized by three key parameters： the Ekman number E, the Poincar6 number Po and the radius-height aspect ratio F. While in an annulus, there is another parameter, the inner-radius-height aspect ratio T, which also plays an important role in controlling the structure and evolution of the flow. By decomposing the nonlinear solution into a set of inertial modes, we demonstrate the properties of both weakly and moderately precessing flows. It is found that, when the precessional force is weak, the flow is stable with a constant amplitude of kinetic energy. As the precessional force increases, our simulation suggests that the nonlinear interaction be- tween the boundary effects and the inertial modes can trigger more turbulence, introducing a transitional regime of rich dynamics to disordered flow. The inertial mode u111, followed by u113 or u112, always dominates the precessing flow when 0.001 ≤Po ≤ 0.05, ranging from weak to moderate precession. Moreover, the precessing flow in an annulus shows more stability than in a cylinder which is likely to be caused by the effect of the inner boundary that restricts the growth of resonant and non-resonant inertial modes. Furthermore, the mechanism of triadic resonance is not found in the transitional regime from a laminar to disordered flow.

关键词： Astrometry and Celestial Mechanics: terrestrial planets -- planets and satellites: interiors-- planets and satellites: instabilities: waves

Enhancing the mechanical properties of casting eutectic high -entropy alloys via W addition

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1364-1372页

作者： Xu Yang Dezhi Chen li Feng gang Qin Shiping Wu Ruirun Chen National Key Laboratory for Precision Hot Processing of Metals School of Material Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

The effect of W element on the microstructure evolution and mechanical properties of Al_(1.25)CoCrFeNi3 eutectic high-entropy alloy and Al_(1.25)CoCrFeNi_(3-x)W_(x)(x=0,0.05,0.1,0.3,and 0.5;atomic ratio)high-entropy alloys(HEAs)were *** show that the Al_(1.25)CoCrFeNi_(3-x)W_(x) HEAs are composed of face-centered cubic and body-centered cubic(BCC)*** W content increases,the microstructure changes from eutectic to *** addition of W lowers the nucleation barrier of the BCC phase,decreases the valence electron concentration of the HEAs,and replaces Al in the BCC phase,thus facilitating the nucleation of the BCC *** results show that the addition of W greatly improves the mechanical properties,and solid-solution,heterogeneous-interface,and second-phase strengthening are the main strengthening *** yield strength,tensile strength,and elongation of the Al_(1.25)CoCrFeNi2.95W0.05 HEA are 601.44 MPa,1132.26 MPa,and 15.94%,respectively,realizing a balance between strength and *** fracture mode of the Al_(1.25)CoCrFeNi_(3-x)W_(x) HEAs is ductile–brittle mixed fracture,and the crack propagates and initiates in the BCC *** eutectic lamellar structure impedes crack propagation and maintains plasticity.

关键词： high-entropy alloy microstructure mechanical property fracture behavior