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An optimization model of parameter matching for aircraft catapult launch

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Chinese Journal of Aeronautics 2020年第1期33卷 191-204页

作者： Zeyang ZHOU jun huang School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China

To efficiently and fully utilize aircraft carrier resources,an optimization model is presented to deal with parameter matching between aircraft and carrier in the process of aircraft catapult *** on carrier aircraft longitudinal dynamic equations and theorem of kinetic energy in catapult launch course,the work characteristics of different forces are learned and a theory model of parameter matching is *** view of the uncertainty of the model parameters of the theory model and the low matching accuracy of the approximate model,an optimization model of parameter matching is introduced in line with the structure of theory model and the approximate model and is generated by the proposed immune genetic *** with the original genetic algorithm and immune algorithm,the proposed algorithm has better calculation accuracy and *** calculation results show that the optimization model occupies certain application value of engineering estimation from the comparison with the relevant literature data and has higher precision than the approximate *** validity of the proposed approach is verified with numerical case study on a carrier based aircraft.

关键词： Aircraft catapult launch Approximate model Immune genetic algorithm Optimization model Parameter matching Theory model

Imitating the Brain with Neurocomputer A"New"Way Towards Artificial General Intelligence

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International Journal of Automation and computing 2017年第5期14卷 520-531页

作者： Tie-jun huang School of Electronic Engineering and Computer Science Peking UniversityBeijing 100871China

To achieve the artificial general intelligence （AGI）, imitate the intelligence？ or imitate the brain？ This is the question! Most artificial intelligence （AI） approaches set the understanding of the intelligence principle as their premise. This may be correct to implement specific intelligence such as computing, symbolic logic, or what the AlphaGo could do. However, this is not correct for AGI, because to understand the principle of the brain intelligence is one of the most difficult challenges for our human beings. It is not wise to set such a question as the premise of the AGI mission. To achieve AGI, a practical approach is to build the so-called neurocomputer, which could be trained to produce autonomous intelligence and AGI. A neurocomputer imitates the biological neural network with neuromorphic devices which emulate the bio-neurons, synapses and other essential neural components. The neurocomputer could perceive the environment via sensors and interact with other entities via a physical body. The philosophy under the ＂new＂ approach, so-called as imitationalism in this paper, is the engineering methodology which has been practiced for thousands of years, and for many cases, such as the invention of the first airplane, succeeded. This paper compares the neurocomputer with the conventional computer. The major progress about neurocomputer is also reviewed.

关键词： Artificial general intelligence (AGI) neuromorphic computing neurocomputer brain-like intelligence imitationalism.

Electrospinning nanofibers to ID,2D,and 3D scaffolds and their biomedical applications

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Nano Research 2022年第2期15卷 787-804页

作者： Huiling Zhong jun huang jun Wu Jianhang Du Guangdong Innovative Engineering and Technology Research Center for Assisted Circulation the Eighth Affiliated Hospital of Sun Yat-sen UniversityShenzhen 518033China Key Laboratory of Sensing Technology and Biomedical Instrument of Guangdong Province School of Biomedical EngineeringSun Yat-sen UniversityGuangzhou 510006China NHC Key Laboratory of Assisted Circulation(Sun Yat-sen University) Guangzhou 510080China

Electrospinning is a popular and effective method of producing porous nanofibers with a large surface area,superior physical and chemical properties,and a controllable pore *** to these properties,electrospun nanofibers can mimic the extracellular matrix and some human tissue structures,based on the fiber ***,the application of electrospun nanofibers as biomaterials,varying from two-dimensional(2D)wound dressings to three-dimensional(3D)tissue engineering scaffolds,has increased rapidly in recent *** can either be uniform fiber strands or coaxial drug carriers,and their overall structure varies from random mesh-like mats to aligned or gradient *** addition,the pore size of the fibers can be adjusted or the fibers can be loaded with disparate medicines to provide different *** review discusses the various structures and applications of 2D fiber mats and 3D nanofibrous scaffolds made up of different one-dimensional(1D)fibers in tissue *** particular,we focus on the improvements made in recent years,especially in the fields of wound healing,angiogenesis,and tissue regeneration.

关键词： electrospinning nanofibers structures three-dimensional(3D)scaffolds tissue engineering

Analysis of drilling difficulty of extended-reach wells based on drilling limit theory

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Petroleum Science 2022年第3期19卷 1099-1109页

作者： Wen-jun huang De-Li Gao MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China

With the continuous increase in vertical depths and horizontal displacements of directional wells,the difficulties of drilling operations continue to increase,and more accurate methods of drilling difficulty evaluation are *** this paper,a drilling difficulty evaluation method is built by combining drilling limit model and expert ***,the concept of drilling difficulty index is introduced,and the method to calculate drilling difficulty index is ***,the meanings of five drilling difficulty levels are explained and the optimization design method with drilling difficulty as the target is *** last,the theoretical model is applied to the extended-reach drilling of the Liuhua oilfield in the South China Sea,in which drilling difficulties are evaluated and the relationship between drilling difficulty and development control radius is *** results indicate that extended-reach drilling in the Liuhua oilfield is on the“normal”difficulty level on average,rotary drilling in 8_(1/2)-*** is the most difficult,and the main constraint conditions are excessive torque and high *** technology upgradation,the drilling difficulties are decreased,the development control radius increases from 6.6 to 11.4 km,and the maximum horizontalto-vertical ratio increases from 5.3 to ***,the development wells in marginal oilfields and adjustment wells in old oilfields can be drilled on“normal”difficulty ***,technology upgradation,especially drilling rig upgradation,is the most important development direction for extended-reach drilling in the South China Sea.

关键词： Extended-reach drilling South China Sea Drilling limit Drilling difficulty evaluation Drilling optimization design

Electromagnetic scattering characteristics of coaxial helicopter based on dynamic transformation method

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Chinese Journal of Aeronautics 2021年第2期34卷 516-528页

作者： Zeyang ZHOU jun huang Jinjun WANG School of Aeronautic Science and Engineering Beihcmg UniversityBeijing 100083China

With the development of coaxial rotors and high-speed helicopters, the electromagnetic scattering characteristics of coaxial helicopters have gradually become a research hotspot. In order to deal with the Radar Cross-Section(RCS) of high-speed rotating rotors or coaxial main rotors, a Dynamic Scattering Method(DSM) based on dynamic process simulation and grid coordinate transformation is presented. Instantaneous electromagnetic scattering from rotors and helicopters is solved using Physical Optics(PO) and Physical Theory of Diffraction(PTD). Important factors are analyzed and discussed in detail, including individual rotor rotation, azimuth, elevation angle,fuselage, pitch angle, and roll angle. The results show that the electromagnetic scattering characteristics of rotor-type components are dynamic and periodic. The dynamic RCS period of a single rotor is related to the dynamic RCS period of the coaxial main rotor. Choosing different observation angles and attitude angles has a great impact on the static and dynamic RCS of the *** presented DSM is effective and efficient to analyze and determine the dynamic electromagnetic scattering characteristics of conventional helicopters or coaxial helicopters.

关键词： Coaxial helicopter Dynamic electromagnetic scattering Radar cross section Radar stealth Rotor

Development cost prediction of general aviation aircraft using combined estimation technique

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Chinese Journal of Aeronautics 2021年第4期34卷 32-41页

作者： Xiaonan CHEN jun huang Mingxu YI School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China

Obtaining accurate development cost estimation results of general aviation aircraft is crucial for companies to adopt the best strategy in the development *** address this problem,this paper proposes a combination of three commonly used single prediction *** optimal weight values of the three single prediction methods are determined by utilizing the shortest ideal point *** cost datasets collected from literature are utilized for fitting and testing the combined prediction method,and the weight coefficients of the three individual prediction methods are calculated as 0.6859,0.0035 and 0.3106,*** results of this study indicate that the developed method has better fitting and estimation accuracy than that of the three individual methods,with average fitting and predicting error values of 2.60%and 6.43%,***,the cost data of military and civil aircraft development from literature are collected for *** results further confirm that the proposed method is not only superior to the single prediction methods in terms of high precision but has wider *** importantly,this research can provide important reference for general aviation aircraft companies in term of product cost planning and corporate sales strategies.

关键词： Combined prediction method General aviation aircraft Optimal weight Shortest ideal point method

Compositional evolution of lava plains in the Syria-Thaumasia Block,Mars

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Science China(Physics,Mechanics & Astronomy) 2014年第5期57卷 994-1000页

作者： huang jun XIAO Long Planetary Science Institute China University of Geosciences Mars Space Flight Facility Arizona State University

Tharsis is the most prominent volcanic province on Mars,yet the compositions of lava flows and how composition relates to the development of Tharsis are poorly *** of Tharsis is covered with air-fall dust,which inhibits spectroscopic determination of lava *** Syria-Thaumasia Block(STB)is a complex tectono-volcanic province closely related to the Tharsis *** lava plains of STB have different emplacement ages,which provide an opportunity to examine whether magma composition changed with the evolution of *** this study,we assessed the lava plains using Thermal Emission Spectrometer(TES)*** derived physical properties,we targeted dust-free regions from four different-aged geological units'surfaces and determined the mineralogical composition by modeling the average TES surface spectrum from each of the four *** units have similar mineralogy but the younger two units have elevated abundance of *** spatial distribution of wrinkle ridges indicates lava plains of unit HNr(older ridged plains material)and Hr(younger ridged plains material)were emplaced before the rise of Tharsis,whereas Hsl(flows of lower member)and Hsu(upper member)were emplaced after Tharsis uplift was *** show that the magma composition differed in the lava plains of STB after the uplift of *** study further characterizes early martian magma composition and evolution.

关键词： Syria-Thaumasia Block lava plains volcanism Tharsis Mars

The Fanconi anemia pathway and DNA interstrand cross-link repair

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Protein & Cell 2011年第9期2卷 704-711页

作者： Xiaoyu Su jun huang Life Sciences Institute Zhejiang UniversityHangzhou 310058China

Fanconi anemia(FA)is an autosomal or X-linked recessive disorder characterized by chromosomal instability,bone marrow failure,cancer susceptibility,and a profound sensitivity to agents that produce DNA interstrand cross-link(ICL).To date,15 genes have been identified that,when mutated,result in FA or an FA-like *** is believed that cellular resistance to DNA interstrand cross-linking agents requires all 15 FA or FAlike ***,we review our current understanding of how these FA proteins participate in ICL repair and discuss the molecular mechanisms that regulate the FA pathway to maintain genome stability.

关键词： Fanconi anemia DNA interstrand crosslink repair FANCD2-FANCI mono-ubiquitylation chromosomal instability

The Multi-sensitivity and Topological Sequence Entropy of Dynamical System with Group Action

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Acta Mathematica Sinica,English Series 2023年第4期39卷 663-684页

作者： Xiao jun huang Bin ZHU College of Mathematics and Statistics Chongqing UniversityChongqing 401331P.R.China Chongqing Key Laboratory of Analytic Mathematics and Applications Chongqing UniversityChongqing 401331P R.China

In this paper,we study the relationship between the multi-sensitivity and the topological maximal sequence entropy of dynamical systems for general group ***,we also discuss the consistency of multi-sensitivity of a dynamical system(G■X)and its hyperspace dynamical system G■K(X).Moreover,we research the relationship between the multi-sensitivity of two dynamical systems and the multi-sensitivity of their product space dynamical ***,we prove that if the topological sequence entropy of G■X vanishes,then so does that of its induced system G■M(X);if the topological sequence entropy of G■X is positive,then that of its induced system G■M(X)is infinity.

关键词： Group action multi-sensitivity topological sequence entropy hyperspace induced system