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Journal of Oceanology and Limnology 2019年第4期37卷 1154-1164页

作者： he jingjing LIN Xiaopei Physical Oceanography Laboratory/CIMST Ocean University of China and Qingdao National Laboratory for Marine Science and Technology

The co-variation of surface wind speed and sea surface temperature (SST) over the Gulf Stream frontal region is investigated using high-resolution satellite measurements and atmospheric reanalysis data. Results show that the pattern of positive SST-surface wind speed correlations is anchored by strong SST gradient and marine atmospheric boundary layer (MABL) height front, with active warm and cold-ocean eddies around. The MABL has an obvious transitional structure along the strong SST front, with greater (lesser) heights over the north (south) side. The significant positive SST-surface wind-speed perturbation correlations are mostly found over both strong warm and cold eddies. The surface wind speed increases (decreases) about 0.32 (0.41) m/s and the MABL elevates (drops) approximate 55 (54) m per 1℃ of SST perturbation induced by warm (cold) eddies. The response of the surface wind speed to SST perturbations over the mesoscale eddies is mainly attributed to the momentum vertical mixing in the MABL, which is confirmed by the linear relationships between the downwind (crosswind) SST gradient and wind divergence (curl).

关键词： Gulf Stream positive sea surface temperature (SST)-surface wind speed correlation marine atmospheric boundary layer (MABL) height mesoscale eddy momentum vertical mixing

Probabilistic inference of fatigue damage propagation with limited and partial information

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Chinese Journal of Aeronautics 2015年第4期28卷 1055-1065页

作者： Huang Min he jingjing Guan Xuefei School of Reliability and System Engineering Beihang University Siemens Corporation Corporate Technology

A general method of probabilistic fatigue damage prognostics using limited and partial information is *** and partial information refers to measurable data that are not enough or cannot directly be used to statistically identify model parameter using traditional regression *** the proposed method, the prior probability distribution of model parameters is derived based on the principle of maximum entropy（Max Ent） using the limited and partial information as *** posterior distribution is formulated using the principle of maximum relative entropy（MRE） to perform probability updating when new information is available and reduces uncertainty in prognosis *** is shown that the posterior distribution is equivalent to a Bayesian posterior when the new information used for updating is point measurements.A numerical quadrature interpolating method is used to calculate the asymptotic approximation for the prior *** the prior is obtained, subsequent measurement data are used to perform updating using Markov chain Monte Carlo（MCMC） *** crack prognosis problems with experimental data are presented for demonstration and validation.

关键词： Fatigue damage propagation Maximum relative entropy Partial information Probability updating Uncertainty

A Lamb wave quantification model for inclined cracks with experimental validation

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Chinese Journal of Aeronautics 2021年第2期34卷 601-611页

作者： jingjing he Haode HUO Xuefei GUAN Jinsong YANG School of Reliability and Systems Engineering Beihang UniversityBeijing 100083China Graduate School of China Academy of Engineering Physics Beijing 100193China CAD/CAM Institute Central South UniversityChangsha 410083China

This paper investigates the influence of crack orientation on damage quantification using Lamb wave in plate structures. Finite element simulation is performed to acquire Lamb wave signal responses for different configurations of crack orientations and crack lengths. Two Lamb wave features, namely the normalized amplitude and the phase change, are used as damage sensitive features to develop a crack size quantification model. A hypothesis based on the geometrical influence on signal features is proposed, and the crack size quantification model incorporating the orientation angle is established using the hypothesis. An index of Probability of Reliable Quantification(PRQ) is proposed to evaluate the performance of the model. The index can be used to determine the sizing risk in terms of probabilities. A realistic aluminum plate is used to obtain the experimental data using piezoelectric(PZT) wafer-type sensors around a center through crack. The experimental data are used to validate the overall method. Results indicate that the proposed model can yield reliable results for size quantification of inclined cracks.

关键词： Crack orientation Crack size quantification model Incident angle Lamb wave Probability of reliable quantification(PRQ)

Seasonal response of surface wind to SST perturbation in the Northern hemisphere

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Journal of Oceanology and Limnology 2019年第4期37卷 1165-1175页

作者： he jingjing HAN Xueshuang LIN Xiaopei Physical Oceanography Laboratory/CIMST Ocean University of China and Qingdao National Laboratory for Marine Science and Technology Qingdao 266003 China Research Vessel Center Ocean University of China Qingdao 266100 China

The seasonal response of surface wind speed to sea surface temperature (SST) change in the Northern hemisphere was investigated using 10 years (2002-2011) high-resolution satellite observations and reanalysis data. The results showed that correlation between surface wind speed perturbations and SST perturbations exhibits remarkable seasonal variation, with more positive correlation is stronger in the cold seasons than in the warm seasons. This seasonality in a positive correlation between SST and surface wind speed is attributable primarily to seasonal changes of oceanic and atmospheric background conditions in frontal regions. The mean SST gradient and the prevailing surface winds are strong in winter and weak in summer. Additionally, the eddy-induced response of surface wind speed is stronger in winter than in summer, although the locations and numbers of mesoscale eddies do not show obvious seasonal features. The response of surface wind speed is apparently due to stability and mixing within the marine atmospheric boundary layer (MABL), modulated by SST perturbations. In the cold seasons, the stronger positive (negative) SST perturbations are easier to increase (decrease) the MABL height and trigger (suppress) momentum vertical mixing, contributing to the positive correlation between SST and surface wind speed. In comparison, SST perturbations are relatively weak in the warm seasons, resulting in a weak response of surface wind speed to SST changes. This result holds for each individual region with energetic eddy activity in the Northern hemisphere.

关键词： seasonality positive correlation sea surface temperature (SST) gradient marine atmospheric boundary layer (MABL) height mesoscale eddy

Fault-tolerant control with mixed aerodynamic surfaces and RCS jets for hypersonic reentry vehicles

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Chinese Journal of Aeronautics 2017年第2期30卷 780-795页

作者： he jingjing Qi Ruiyun Jiang Bin Zhai Rongyu College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 211106 China

This paper proposes a fault-tolerant strategy for hypersonic reentry vehicles with mixed aerodynamic surfaces and reaction control systems（RCS） under external disturbances and subject to actuator *** surfaces are treated as the primary actuator in normal situations,and they are driven by a continuous quadratic programming（QP） allocator to generate torque commanded by a nonlinear adaptive feedback control *** aerodynamic surfaces encounter faults,they may not be able to provide sufficient torque as commanded,and RCS jets are activated to augment the aerodynamic surfaces to compensate for insufficient *** loss of effectiveness and stuck faults are considered in this paper,and observers are designed to detect and identify the *** on the fault identification results,an RCS control allocator using integer linear programming（ILP） techniques is designed to determine the optimal combination of activated RCS *** treating the RCS control allocator as a quantization element,closed-loop stability with both continuous and quantized inputs is *** results verify the effectiveness of the proposed method.

关键词： Control allocation Fault-tolerant control Hypersonic vehicles Quantized control Reaction control system(RCS)

Comparative study between crack closure model and Willenborg model for fatigue prediction under overload effects

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Chinese Journal of Aeronautics 2016年第6期29卷 1618-1625页

作者： Jiang Shan Zhang Wei he jingjing Wang Zili Science and Technology on Reliability and Environmental Engineering Laboratory School of Reliability and Systems Engineering Beihang University

A comparative study is performed between a crack closure model and the Willenborg model, which can calculate the fatigue crack growth rate under the overload effects. The modified virtual crack annealing(VCA) model is briefly reviewed, which is based on the equivalent plastic zone concept. In this method, the retardation phenomenon is explained by the crack closure level variation, which is derived from the interactions between forward and reverse plastic zones ahead of the crack tip. As a comparison, the Forman equation in conjunction with the Willenborg model is also reviewed. The retardation phenomenon is described by directly modifying the stress intensity factor. It is known that the large plastic zone created by the overload can decelerate the fatigue crack growth rate until the crack grows beyond this region. A relationship between the plastic zone and the modified stress intensity factor is developed, which is a mathematical fitting equation instead of physical-based formulation. The experimental data in aluminum alloys are used to validate these two models. Overall, good agreement is observed between the model predictions and the testing data. It is noted that the approach based on modified VCA model can give more accurate prediction curves than the Willenborg model.

关键词： Crack closure Fatigue crack growth Interaction effects Overloads Plastic zone

Advances in cycloaddition and hydroaddition reaction of α -(trifluoromethyl)styrenes without defluorination: An alternative approach to CF_(3) -containing compounds

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Chinese Chemical Letters 2022年第5期33卷 2363-2371页

作者： Yupian Deng jingjing he Song Cao Xuhong Qian Shanghai Key Laboratory of Chemical Biology School of PharmacyEast China University of Science and Technology(ECUST)Shanghai 200237China School of Chemistry and Molecular Engineering East China Normal UniversityShanghai 200062China

α-(Trifluoromethyl)styrene and its derivatives have found wide applications in the fields of pharmaceuti-cals,agrochemicals,and advanced *** are also versatile trifluoromethyl-containing building blocks for the preparation of various trifluoromethyl-containing,fluorine-containing or nonfluorinated ***,great efforts have been made to develop diverse reactions for rapidly accessing a wide range of valuable gem–difluoroalkenes and gem–difluoroalkylated compounds via defluorinative re-action or the defluorinative ipso-functionalization reaction ofα-(trifluoromethyl)styrenes,*** contrast,α-(trifluoromethyl)styrenes remain notably underdeveloped with respect to their use in cycload-dition and hydroaddition reaction with retaining of three C–F *** short review herein is aimed to summarize the recent progress on the cycloaddition and hydroaddition reaction including nucleophilic,radical and transition metal-catalyzed addition ofα-(trifluoromethyl)styrenes without accompanying de-fluorination.

关键词： α-(Trifluoromethyl)styrenes Cycloaddition and hydroaddition Nondefluorination CF 3-containing compounds

Fuzzy control decision-making framework adapted to the uncertainty environment of complex software system

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International Journal of Modeling, Simulation, and Scientific Computing 2022年第2期13卷 168-186页

作者： jingjing he Liwei Zheng Zhanqi Cui Computer School Beijing Information Science and Technology UniversityBeijing 100101China

As the system becomes more intelligent and embedded,the operating environment is gradually changed from closed,static,and controllable to more open,dynamic,and difficult to *** a result,the design of complex software systems is faced with many challenges arising from the uncertainty of the environment(UoE).On the one hand,ignoring the UoE to manually describe requirements is not only a tough job,but it can also hinder the discovery of potential requirements;on the other hand,it is a challenge to integrate the representation of and reasoning of UoE into the process of modeling complex *** on the analysis of the characteristics of complex systems engineering,this paper takes solving the UoE caused by stakeholders prefer-ences and complex environment context as the entry point and designs a fuzzy con-trol decision-making ***,the framework contributes to the spiral of complex systems while solving the UoE by constructing a closed-loop intelligent sys-tem based on automatic data flow between information space and physical space for environment sensing,uncertainty analysis,requirements mining,fuzzy reasoning,deci-sion execution as well as feedback ***,the framework is validated with a concrete example of an adaptive treadmill system based on the support tools developed.

关键词： UoE decision making fuzzy control

Waste to treasure:Reutilization of fluid catalytic cracking coke block as photothermal conversion material for water evaporation

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Particuology 2024年第5期88卷 62-70页

作者： Zhuwei Gao Chengxin Li jingjing he Zhuo Wang Xinyu Qi Lan he Shihao Wang Zhongxin Liu School of Chemical Engineering and Technology Hainan UniversityHaikou 570228China TJ-YZ School of Network Science Haikou University of EconomicsHaikou 570203China School of Food Science and Engineering Hainan UniversityHaikou 570228China Key Laboratory of Advanced Materials of Tropical Island Resources of Ministry of Education Hainan UniversityHaikou 570228China Hainan Provincial Key Laboratory of Fine Chemicals Hainan UniversityHaikou 570228China

This study aims to analyze the coking process and propose an effective method for the reutilization of fluid catalytic cracking(FCC)coke ***,we analyzed the basic characteristics and chemical composition of FCC coke *** results showed that the main components were carbon,oxygen,and aluminum,accounting for 60.8%,26.6%,and 11.5%,*** the conventional catalytic cracking reaction temperature from 500℃ to 600℃,the formation of the first aromatic hydrocarbon was particularly important for the formation of *** condensation of oil-gas-entrained catalyst particles and their heavy components was the physical cause of coking,while the dehydrogenation condensation reaction of oil-gas heavy components was the chemical *** addition,the membrane prepared by powdered coke had excellent photothermal conversion ability,which could be heated to more than 110℃ within 360 s under two fixed light *** evaporation rate of photothermal water was 5.89 kg m^(2) h^(−1),which has great industrial application *** works provide a novel and effective method of separation membrane for the reutilization of FCC coke blocks.

关键词： Coking process Reutilization of FCC coke Carbonaceous deposition Membrane Photothermal conversion

Et_(3)N-Catalyzed Cycloaddition Reactions ofα-(Trifluoromethyl)styrenes with 2,2,2-Trifluorodiazoethane to Access Bis(trifluoromethyl)-Substituted Pyrazolines

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Chinese Journal of Chemistry 2021年第2期39卷 301-306页

作者： Chunmei Li Xuxue Zhang jingjing he Sixue Xu Song Cao Shanghai Key Laboratory of Chemical Biology School of PharmacyEast China University of Science and TechnologyShanghai200237 China College of Chemistry and Chemical Engineering Qilu Normal UniversityJinanShandong250200 China

A novel and practical method for the synthesis of 3,5-bis(trifluoromethyl)-4,5-dihydro-1H-pyrazoles by [3+2] cycloaddition reactions of α-(trifluoromethyl)styrenes with 2,2,2-trifluorodiazoethane (CF3CHN2) has been developed. The cyclization reaction proceeds smoothly in the presence of a catalytic amount of Et_(3)N, affording a variety of bis(trifluoromethyl)-substituted 2-pyrazolines in good to excellent yields. This method also exhibits a broad substrate scope and tolerates various functional groups.

关键词： Cycloaddition 2,2,2-Trifluorodiazoethane α-(Trifluoromethyl)styrenes Pyrazoline Et_(3)N-catalyzed