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Study of the Viscosity and Specific Gravity of the Ternary Used Frying Oil (UFO)-Bioethanol-Diesel System

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Journal of Materials Science and Chemical Engineering 2024年第4期12卷 53-66页

作者： konan Edmond Kouassi Abollé Abolle N’guessan Luc Brou David Boa N’guessan Raymond Kre Kouassi Benjamin yao Laboratoire de Thermodynamique et Physico-Chimie du Milieu (LTPCM) UFR-SFA UNA Abidjan C&#244te d&#8217Ivoire Laboratoire de Physiques Fondamentales et Appliqué es (LPFA) UFR-SFA UNA Abidjan C&#244te d&#8217Ivoire Laboratoire des Procé d&#233s Industriels de Synth&#232se de l&#8217Environnement et des Energies Nouvelles (LAPISEN) de l&#8217Institut National Polytechnique F&#233lix Houphou&#235t Boigny de Yamoussoukro Yamoussoukro C&#244te d&#8217Ivoire

Fossil fuels cover around 80% of global energy consumption. However, the problems linked to their use justify the choice of using biofuel. In order to reduce as much as possible, diesel rate, an increase in the number of additives may be considered. Thus, in this work, the study of the used frying oil (UFO), bioethanol and diesel ternary system was undertaken. It emerges from this study that the addition of bioethanol reduces the viscosity and the density of the ternary system and permits a 90% substitution rate for diesel between the UFO and bioethanol. Finally, the percentage of oil becomes 40% after adding alcohol compared to the binary diesel crude vegetable oil mixture where this rate is 30%.

关键词： Biofuel UFO-Bioethanol-Diesel Ternary Density Viscosity

A deformation criterion of pressurized non-circular cross-section cabin and its effects on cruise performance of BWB civil aircraft

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Chinese Journal of Aeronautics 2024年第6期37卷 78-88页

作者： Siyi GUO Zhenli CHEN Xuanyu yao School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Aero Engine Academy of China Beijing 101304China

Blended-Wing-Body(BWB)aircraft is promoted as one of the most possible layouts to achieve more sustainable civil *** to the non-circular cross-section of the center-body,a bulge deformation forms over the upper surface of the body under the coupled loads of the internal pressurization of the cabin and the aerodynamic bending moments of the wing,which reduces the lift-to-drag ratio of BWB *** a limited deformation,the relationship between the aerodynamic performance and the structural weight needs to be *** this work,the effects of stiffness constraints on the center-body deformation,structural weight of the airframe and aerodynamic performance were investigated by using an analytical model of the Pultruded Rod Stitched Efficient Unitized Structure(PRSEUS)for the airframe and the computational fluid dynamics method,*** results show that as the stiffness constraint increases,the spacings between the rod stringers and the frame stiffeners decrease,and the structural weight increases inversely.A 5.2% reduction of the lift-to-drag ratio is encountered at cruise for a medium deformation design of 42.8 mm/m.A higher aerodynamic penalty is suffered when the stiffness constraint is further *** final deformation criterion is different when the weight vector of the aerodynamic performance and structural weight is different.

关键词： Blended-Wing-Body(BWB) Deformation PultrudedRod Stitched Effi-cient Unitized Structure(PRSEUS) Cabin structure Stiffness constraint

Initial costates derived by near-optimal reference sequence and least-squares method

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Chinese Journal of Aeronautics 2024年第5期37卷 377-391页

作者： Shaozhao LU yao ZHANG Quan HU School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

In this paper,we present a novel initial costates solver for initializing time-optimal trajectory problems in relative motion with continuous low *** proposed solver consists of two primary components:training a Multilayer Perceptron(MLP)for generating reference sequence and Time of Flight(TOF)to the target,and deriving a system of linear algebraic equations for obtaining the initial *** overcome the challenge of generating training samples for the MLP,the backward generation method is proposed to obtain five different training *** training database and sample form are determined by analyzing the input and output correlation using the Pearson correlation *** best-performing MLP is obtained by analyzing the training results with various hyper-parameter combinations.A reference sequence starting from the initial states is obtained by integrating forward with the near-optimal control vector from the output of ***,a system of linear algebraic equations for estimating the initial costates is derived using the reference sequence and the necessary conditions for *** results demonstrate that the proposed initial costates solver improves the convergence ratio and reduce the function calls of the shooting ***,Monte-Carlo simulation illustrates that the initial costates solver is applicable to different initial velocities,demonstrating excellent generalization ability.

关键词： Relative motion Expanding training database Multilayer perceptron Initial costates Least-squares method

Lesson Learned from COVID-19 Retrospective Study: An Entropy-Based Clinical-Interpretable Scorecard for Mortality Risk Control at ICU Admission

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Tsinghua Science and Technology 2024年第1期29卷 34-45页

作者： Chong yao Chonghui Huangqi Anpeng Huang Laboratory of Network Information Security Beihang UniversityBeijing 100191China Andrew and Erna Viterbi School of Engineering University of Southern CaliforniaLos AnglesCA 90089USA Beijing Goodwill Information and Technology Co. Ltd.and Mobile Health LaboratoryPeking UniversityBeijing 100871China

With severe acute respiratory syndrome coronavirus 2 spreading globally and causing 2019 coronavirus disease(COVID-19),a challenge that we unprepared for was about how to optimally plan and distribute limited top-medical resources for patients in need of urgent *** address this challenge,physicians desperately needed a scientific tool to methodically differentiate between cases with varying *** this study,the unique data of COVID-19 intensive care unit(ICU)patients provided by the national medical team in Wuhan were classified into discrete and continuous variable *** continuous data were discretized using an entropy-based method and transformed into serial information margins,in which each information margin is related to a specific symptom or clinical ***,all these native and processed discrete data were used to configure a readable scorecard through logistic regression,which is the desired scientific tool aforementioned.A total of 322 ICU patients(age:[median:64,interquartile range:54-75],males:178[55.28%],and death:72[22.36%])were included in the *** of mortality in COVID-19 patients can be evaluated using a scorecard model(calibration slope:1.343,Brier:0.048,Dxy=0.972,and population stability index=0.071),with desired model performances(accuracy=0.948,area under curve=0.99,sensitivity=1,and specificity=0.939).This new model can interpret clinical meanings from complex data,and compare it with existing machine learning methods through a black-box *** new data-information model answers a critical question of how a computing algorithm produces clinically meaningful results that will help physicians logically allocate medical resources for COVID-19 ***,this tool has limitations,giving that this research is a retrospective ***,this tool will be tested further and optimized for adaptation to similar clinical cases in the future.

关键词： COVID-19 scorecard clinical-interpretable machine learning ICU admission control

Expression Recognition Method Based on Convolutional Neural Network and Capsule Neural Network

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Computers, Materials & Continua 2024年第4期79卷 1659-1677页

作者： Zhanfeng Wang Lisha yao School of Computer Science and Artificial Intelligence Chaohu UniversityHefei238000China School of Big Data and Artificial Intelligence Anhui Xinhua UniversityHefei230088China

Convolutional neural networks struggle to accurately handle changes in angles and twists in the direction of images,which affects their ability to recognize patterns based on internal feature levels. In contrast, CapsNet overcomesthese limitations by vectorizing information through increased directionality and magnitude, ensuring that spatialinformation is not overlooked. Therefore, this study proposes a novel expression recognition technique calledCAPSULE-VGG, which combines the strengths of CapsNet and convolutional neural networks. By refining andintegrating features extracted by a convolutional neural network before introducing theminto CapsNet, ourmodelenhances facial recognition capabilities. Compared to traditional neural network models, our approach offersfaster training pace, improved convergence speed, and higher accuracy rates approaching stability. Experimentalresults demonstrate that our method achieves recognition rates of 74.14% for the FER2013 expression dataset and99.85% for the CK+ expression dataset. By contrasting these findings with those obtained using conventionalexpression recognition techniques and incorporating CapsNet’s advantages, we effectively address issues associatedwith convolutional neural networks while increasing expression identification accuracy.

关键词： Expression recognition capsule neural network convolutional neural network

Quantum Curve and Bilinear Fermionic Form for the Orbifold Gromov–Witten Theory of P[r]

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Acta Mathematica Sinica,English Series 2024年第1期40卷 43-80页

作者： Chong yao CHEN Shuai GUO Mathematics Department Duke UniversityBox 90320DurhamNC 27708-0320USA School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China

We construct the quantum curve for the Baker-Akhiezer function of the orbifold Gromov-Witten theory of the weighted projective line P[r].Furthermore,we deduce the explicit bilinear Fermionic formula for the(stationary... 详细信息

关键词： Quantum curve Free Fermions Gromov-Witten invariants Orbifold P^(1)

Summer extreme precipitation patterns and synoptic-scale circulation precursors over the Tibetan Plateau

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Science China Earth Sciences 2024年第5期67卷 1625-1638页

作者： Zhiyuan DING yao HA Zhong ZHONG College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Key Laboratory for Virtual Geographic Environment School of Geography ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Collaborative Innovation Center for Climate Change School of Atmospheric SciencesNanjing UniversityNanjing 210023China

In the context of global warming,the extreme summer precipitation over the Tibetan Plateau(TP)has changed *** this study,the summer(June–August)extreme precipitation on the TP was classified into three spatial types by applying the K-means clustering method to the Third Pole Region long time-series high-resolution(1/30°)precipitation dataset(TPHi Pr,1979–2020).The characteristics of the circulation anomalies and precursors corresponding to the extreme precipitation on the TP in summer during 1979–2020 were *** results showed that the summer extreme precipitation of the TP can be categorized into northwestern(NW),southeastern(SE),and southern Himalayan(HS)types based on extreme precipitation *** NW and SE types are mainly influenced by anomalous signals in the mid-to-high latitude regions upstream of them,whereas the HS type is controlled by the localized subtropical anomalous *** the 8th day before the onset of the NW type,an anomalous cyclone was observed in the western Atlantic Ocean(60°W,50°N),which triggered the west-to-east quasi-latitudinal propagation of Rossby *** the onset day of the NW type,the upper troposphere showed positive-negative-positive geopotential height anomalies along the latitudinal 40°N from the Caspian Sea,the western part of Xinjiang,to the northeastern *** entered from the Arabian Sea along the southeastern edge of the anomalous cyclone on the southwestern TP and converged in the northwestern *** to the NW type,the precursors of the SE type appeared at higher latitudes and were more *** the 8th day before the onset of the SE type,an anomalous cyclone occurred near Greenland(60°W,70°N)and excited Rossby waves propagating *** the onset day of the SE type,the upper troposphere showed negative-positive-negative geopotential height anomalies across Eurasia from the Ural Mountains and the Iranian Plateau to the northern TP in the northwest-southeast directi

关键词： Tibetan Plateau Summer extreme precipitation Atmospheric circulation anomaly Precursor Teleconnection wave train

Dual-assisted high-precision tracking technique for wideband multiplexed signals in new generation GNSS

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Satellite Navigation 2024年第1期5卷 52-73页

作者： Yunhan Qi Zheng yao Mingquan Lu Department of Electronic Engineering Tsinghua UniversityBeijing100084China Beijing National Research Center for Information Science and Technology Beijing100084China

With the evolution of Global Navigation Satellite System(GNSS),new generation GNSS signals have adopted the dual-frequency multiplexing modulation techniques,which jointly modulate multiple signals located on multiple sub-frequencies into a Wideband Multiplexed Signal(WMS).Although WMSs were proposed initially to reduce the complexity of satellite transmitters and improve the transmission efficiency of signals,their multi-component structures and wide root mean square bandwidths introduced by high-frequency subcarriers also provide the possibility to improve the GNSS ranging ***,this paper proposes a Dual-assisted Multi-component Tracking(DMT)technique,which can not only fully use high-frequency subcarriers in WMSs,but also effectively track carrier,subcarrier,and code by jointly utilizing all components in *** this paper,the tracking and ranging performances of DMT are comprehensively analyzed theoretically and by simulation and real *** results show that compared with existing WMS tracking methods,DMT can achieve tracking results with lower tracking jitters and ranging results with higher precision,providing a highly advantageous solution for new generation GNSS signal processing.

关键词： Wideband multiplexed signal Dual-assisted Multi-component High precision tracking

Stabilization of cathode electrolyte interphase for aqueous zinc-ion batteries

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Journal of Energy Chemistry 2024年第9期96卷 359-386页

作者： Zhenjie yao Wenyao Zhang Junwu Zhu Key Laboratory for Soft Chemistry and Functional Materials Ministry of Education Nanjing University of Science and TechnologyNanjing 210094JiangsuChina

Aqueous zinc-ion battery systems are attractive for next-generation energy storage devices,however,the unstable electrode electrolyte interphase,especially cathode electrolyte interphase(CEI),has induced rapid capacity attenuation,insufficient cycle life,and severe safety *** the researching of CEI formation,composition,dynamic structure,and reaction mechanisms would help in understanding the fundamental electrochemistry at CEI such as electron and ion transport processes,further strengthening the specific capacity,rate,and cycle performance of the cathode *** this review,we summarized the latest progress in understanding interfacial reaction mechanisms and ion dynamic behavior,emphasizing the impact of surface-specific adsorption and solvation behaviors on the interface's ultimate structure and chemical ***,the significant challenges that persist in CEI formation mechanisms,such as cathodic dissolution,by-product formation,electrostatic interactions,constrained electrochemical windows,oxygen evolution reaction,overpotentials,phase transitions,and additional factors,were *** challenges are explored to identify triggers contributing to the depletion of active materials and alterations in the composition or state of the ***,with a deep comprehension of interfacial behaviors,the review articulates innovative optimization strategies through a detailed categorization of approaches in electrolyte engineering,cathode engineering,and artificial CEI ***,future challenges and development directions of CEI are *** hope to offer insights for constructing robust CEI films to achieve high performance aqueous zinc-ion batteries.

关键词： Aqueous zinc-ion batteries Cathode-electrolyte interphase Energy storage