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DBN-GABP model for estimation of aircraft wake vortex parameters using Lidar data

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Chinese Journal of Aeronautics 2024年第9期37卷 347-368页

作者： Zhiqiang WEI Tong lu Runping gu Fei LIU College of Air Traffic Management Civil Aviation University of ChinaTianjin 300300China

Aircraft wake turbulence is an inherent outcome of aircraft flight,presenting a substan-tial challenge to air traffic control,aviation safety and operational *** upon data obtained from coherent Doppler Lidar detection,and combining Dynamic Bayesian Networks(DBN)with Genetic Algorithm-optimized Backpropagation Neural Networks(GA-BPNN),this paper proposes a model for the inversion of wake vortex *** the wake vortex flow field simulation analysis,the wind and turbulent environment were initially superimposed onto the simulated wake velocity ***,Lidar-detected echoes of the velocity field are simulated to obtain a data set similar to the actual situation for model *** the case study validation,real measured data underwent preprocessing and were then input into the established *** allowed us to construct the wake vortex characteristic parameter inversion *** final results demonstrated that our model achieved parameter inversion with only minor *** a practical example,our model in this paper significantly reduced the mean square error of the inverted velocity field when compared to the traditional *** study holds significant promise for real-time monitoring of wake vortices at airports,and is proved a crucial step in developing wake vortex interval standards.

关键词： Air traffic control Wake vortex flow field simulation Lidar echo simulation DBNmodel GA-BP model Wakevortex characteristic parameter inversion model

Recent development of efficient electrocatalysts derived from porous organic polymers for oxygen reduction reaction

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Science China Chemistry 2017年第8期60卷 999-1006页

作者： Shuanglong lu Yinghua Jin Hongwei gu Wei Zhang Department of Chemistry and Bioehemistry University of Colorado Boulder CO 80309 USA

Porous organic polymers(POPs) have recently emerged as promising candidates for catalyzing oxygen reduction reaction(ORR).Compared to conventional Pt-based ORR catalysts, these newly developed porous materials, including both non-precious metal based catalysts and metal-free catalysts, are more sustainable and cost-effective. Their porous structures and large surface areas facilitate mass and electron transport and boost the ORR kinetics. This mini-review will give a brief summary of recent development of POPs as electrocatalysts for the ORR. Some design principles, different POP structures, key factors for their ORR catalytic performance, and outlook of POP materials will be discussed.

关键词： porous organic polymers oxygen reduction reaction electrocatalysis metalloporphyrin

Ligand-Controlled Copper-Catalyzed Highly Regioselective Difluoromethylation of Allylic Chlorides/Bromides and Propargyl Bromides

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Chinese Journal of Chemistry 2018年第1期36卷 55-58页

作者： Yang gu Changhui lu Yucheng gu Qilong Shen Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry University of Chinese Academy Sciences Chinese Academy of Sciences 345 Lingling Road Shanghai 200032 China Syngenta Jealott's Hill International Research Cente Bracknell Berkshire RG42 6EY UK

Highly regiodivergent copper-catalyzed allylic/propargylic difluoromethylation reactions by employing different ligands are described. When 5,6-dimethyl-1,10-phenanthroline was used as the ligand, exclusively α-difluoromethylated products were obtained, while γ-selective difluoromethylated products were generated when N-heterocyclic carbene-SIPr was used as the ligand. Likewise, high α- vs. γ-selectivities were achieved in the presence of similar copper catalysts for the reactions of propargyl bromides. Moreover, a copper-catalyzed asymmetric allylic difluoromethylation reaction with moderate to good enantioselectivity by the use of chiral ligands was developed.

关键词： fluorine difluoromethyl copper asymmetric allylic substitution

Adaptive Simplified Chicken Swarm Optimization Based on Inverted S-Shaped Inertia Weight

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Chinese Journal of Electronics 2022年第2期31卷 367-386页

作者： gu Yanchun lu Haiyan XIANG Lei SHEN Wanqiang School of Science Jiangnan University Wuxi Engineering Technology Research Center for Biological Computing Jiangnan University

Considering the issues of premature convergence and low solution accuracy in solving high-dimensional problems with the basic chicken swarm optimization algorithm, an adaptive simplified chicken swarm optimization algorithm based on inverted S-shaped inertia weight(ASCSO-S) is proposed. Firstly, a simplified chicken swarm optimization algorithm is presented by removing all the chicks from the chicken swarm. Secondly, an inverted S-shaped inertia weight is designed and introduced into the updating process of the roosters and hens to dynamically adjust their moving step size and thus to improve the convergence speed and solution accuracy of the algorithm. Thirdly, in order to enhance the exploration ability of the algorithm, an adaptive updating strategy is added to the updating process of the *** experiments on 21 classical test functions show that ASCSO-S is superior to the other comparison algorithms in terms of convergence speed, solution accuracy, and solution stability. In addition, ASCSO-S is applied to the parameter estimation of Richards model, and the test results indicate that ASCSO-S has the best fitting results compared with other three algorithms.

关键词： particle swarm optimisation solution stability adaptive simplified chicken swarm optimization algorithm parameter estimation Richards model solution accuracy swarm intelligence inverted S-shaped inertia weight convergence speed adaptive updating strategy convergence updating process ASCSO-S

Formation and evolution of the tertiary carbonate reefs in the Madura Strait Basin of Indonesia

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Journal of Oceanology and Limnology 2019年第1期37卷 47-61页

作者： RAN Weimin luAN xiwu lu Yintao LIU Hong YANG Jiajia ZHAO Yang HE Wenchang YAN Zhonghui College of Marine Geosciences Ocean University of China Evaluation and Detection Technology Laboratory of Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Qingdao Institute of Marine Geology Petro China Hangzhou Research Institute of Geology China Petroleum Pipeline Engineering Co. Ltd. (Engineering) China University of Petroleum

Analysis of 2 D seismic data over 4 500 km in length from the Madura Strait Basin in the East Java Sea reveals seismic re?ection characteristics of reefs and associated sedimentary bodies, including asymmetrical or symmetrical dome re?ections, slope progradational re?ections, chaotic re?ections and discontinuous strong re?ections inside the reef, which onlap the ?ank of the reef. It is concluded that the developmental paleo-environment of most reefs is mainly conducive to shallow marine carbonate platform facies and platform margin facies, based on well core data, variations in seismic facies and strata *** formation and evolution of all reefs are primarily in?uenced by the tectonic framework of the Madura Strait Basin. Platform margin reefs are principally controlled by two types of structures: one is a series of E-W trending Paleogene normal faults, and the other is an E-W trending Neogene inversion structures. In addition, wave actions, tidal currents and other ocean currents play an accelerated role in sorting, rounding and redeposition for the accumulation and evolution of reefs. Tertiary reefs in the MSB can be divided into four types: 1) an open platform coral reef of Late Oligocene to Early Miocene, 2) a platform margin coral reef controlled by normal faults in Late Oligocene to Early Miocene, 3) a platform margin Globigerina moundreef controlled by a "hidden" inversion structure in Early Pliocene, and 4) a platform margin Globigerina mound-reef controlled by thrust faults in the early Pliocene. Patterns of the formation and evolution of reefs are also suggested.

关键词： reef seismic reflection characteristics formation and evolution Tertiary Madura Strait Basin,Indonesia

Acoustics Based Monitoring and Diagnostics for the Progressive Deterioration of Helical Gearboxes

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Chinese Journal of Mechanical Engineering 2021年第4期34卷 98-109页

作者： Kaibo lu James Xi gu Hongwei Fan Xiuquan Sun Bing Li Fengshou gu College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024China School of Engineering University of BoltonBolton BL35ABUK College of Mechanical Engineering Xi’an University of Science and TechnologyXi’an 710054China Centre for Efficiency and Performance Engineering University of HuddersfieldHuddersfield HD13DHUK. School of Industrial Automation Beijing Institute of TechnologyZhuhai 519088China

Gearbox condition monitoring(CM)plays a significant role in ensuring the operational reliability and efficiency of a wide range of critical industrial systems such as wind turbines and *** and timely diagnosis of gear faults will improve the maintenance of gearboxes operating under sub-optimal conditions,avoid excessive energy consumption and prevent avoidable damages to *** study focuses on developing CM for a multi-stage helical gearbox using airborne *** on signal phase alignments,Modulation Signal Bispectrum(MSB)analysis allows random noise and interrupting events in sound signals to be suppressed greatly and obtains nonlinear modulation features in association with gear *** coherence is evaluated for selecting the reliable bi-spectral peaks for indication of gear deterioration.A run-to-failure test of two industrial gearboxes was tested under various loading *** omnidirectional microphones were fixed near the gearboxes to sense acoustic information during *** has been shown that compared against vibration based CM,acoustics can perceive the responses of vibration in a larger areas and contains more comprehensive and stable information related to gear dynamics variation due to ***,the MSB magnitude peaks at the first three harmonic components of gear mesh and rotation components are demonstrated to be sufficient in characterizing the gradual deterioration of gear ***,the combining of MSB peaks with baseline normalization yields more accurate monitoring trends and diagnostics,allowing the gradual deterioration process and gear wear location to be represented more consistently.

关键词： Acoustics Modulation Signal Bispectrum Helical gearbox Gear wear

New degradation call admission control for increasing WCDMA system capacity

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Journal of Systems Engineering and Electronics 2006年第4期17卷 750-754页

作者： Liu Ningqing lu Zhi gu Xuemai Dept. Electronics and Communication Engineering Harbin Inst. of Technology Harbin 150001P.R. China

Propose a new degradation call admission control（DCAC）scheme, which can be used in wideband code division multiple access communication system. So-called degradation is that non-real time call has the characteristic of variable bit rate, so decreasing its bit rate can reduce the load of the system, consequently the system can admit new call which should be blocked when the system is close to full load, therefore new call＇s access probability increases. This paper brings forward design project and does system simulation, simulation proves that DCAC can effectively decrease calls＇ blocking probability and increase the total number of the on-line users.

关键词： degradation call admission control WCDMA call block probability.

Causal Viscosity in Global Dynamics of Advection-Dominated Accretion Flows Around Black Holes

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Chinese Physics Letters 2000年第2期17卷 151-153页

作者： gu Wei-Min lu Ju-Fu Center for Astrophysics University of Science and Technology of ChinaHefei 230026 National Astronomical Observatories Chinese Academy of Sciences

We modify the viscosity to disappear inside the sonic point in the advection-dominated accretion flows (ADAF's) around black holes, and obtain the causally connected, physically self-consistent ADAF-thin disk solutions. Such global solutions differ from previous ones in quantitative details. The results show that the range of variation for the value of the outer boundary Rout is very large, from 30Rg to 106Rg. There is a narrow region for which the rotating motion of the flow is super-Keplerian in each global solution. An example global solution with the causal viscosity is given explicitly, for which R8=2.28Rg and j=1.7564(cRg).

关键词： viscosity global details

Radial Shocks in Advection-Dominated Accretion Flows Around Black Holes

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Chinese Physics Letters 2001年第1期18卷 148-150页

作者： gu Wei-Min lu Ju-Fu Center for Astrophysics University of Science and Technology of ChinaHefei 230026 National Astronomical Observatories Chinese Academy of SciencesBeijing 100012 Department of Physics Xiamen UniversityXiamen 361005

We have solved the set of equations for advection-dominated accretion flows(ADAFs)around black holes,and found a new class of global solutions with standing radial ***α-X-type shocks may exist in flows when 0≤αlution is given explicitly,for whichα=0.01 andγ=*** shock position is R_(sh)=8.68R_(g),which is between the inner sonic point R_(s1)=3.88R_(g) and the outer sonic point R_(s2)=85.92R_(g).

关键词： flows outer explicitly