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Pilot time-varying control behavior modeling in refractory period with aircraft failures

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Science China(Technological Sciences) 2023年第7期66卷 2000-2012页

作者： XU ShuTing TAN WenQian wang weijun SUN LiGuo School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Nanchang 330000China

Modeling human pilot control behavior aims to understand and describe how humans control aircrafts and devices,to provide a foundation for the study of the dynamic characteristics of the human-vehicle *** the presence of aircraft failures,the human pilot has a control process of the refractory period,which may cause adverse aircraft-pilot couplings,and even lead to loss-of-control *** refractory period will make the pilot emerge with time-varying and adaptive *** paper investigates how pilot control behavior changes to adapt to the aircraft failure situation and develops a time-varying pilot model during the refractory *** aviation pilots performed a human-in-the-loop simulation experiment on a ground flight simulator to simulate the failure situations for a pitch-tracking *** characterize the pilot’s time-varying response mechanism,a time-frequency-spectrum method was used to analyze the pilot control *** innovations in the proposed model can be embodied in the description of the fuzziness,time-varying,and adaptation of the pilot for the failures in the refractory *** on fuzzy logic theory,the pilot’s judgment and identification of failures are *** adaptation of manual control behavior to time-varying aircraft dynamics is depicted by adaptive model ***-domain and time-frequency-spectrum analysis show that the simulation results of the pilot model are consistent with the human-in-the-loop experimental *** model simulation evaluations are within the range of the experimental evaluation,which shows the rationality of the timevarying behavior model of the human pilot in a failure refractory *** model has practical values for guiding the pilot to deal with abnormal conditions and predicting nonlinear aircraft-pilot couplings.

关键词： time-varying system human pilot model fuzzy control simulation aircraft-pilot couplings

Transmission of oxygen isotope signals of precipitation-soil water-drip water and its implications in Liangfeng Cave of Guizhou,China

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Chinese Science Bulletin 2008年第21期53卷 3364-3370页

作者： LUO weijun wang ShiJie State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

According to systemically monitoring results of oxygen(hydrogen) isotope compositions of precipita-tion,soil waters,soil CO2,cave drip waters and their corresponding speleothems in Liangfeng Cave(LFC) in Guizhou Province,Southwest China,it is found that local precipitation is the main source of soil waters and drip waters,and that the amplitudes of those δ 18O values of three waters(precipitation,soil water and drip water) decrease in turn in the observed year,which are 0‰ to -10‰, -2‰ to -9‰ and -6‰ to -8‰,***,the δ 18O values for three waters show a roughly simultaneous variation,namely,that those values are lighter in the rainy seasons,weightier in the dry seasons,and that the average δ 18O value of drip waters is about 0.3‰ weightier than that of precipitation,which is modified by surface evaporation *** also find that oxygen isotope equilibrium is reached or neared in the formation processes of speleothems in LFC system,and that it is feasible to reconstruct paleotemperature and paleoprecipitation by using δ 18O values of ***,it should be noted that surface evaporation would affect the oxygen isotope values in the study area.

关键词：贵州氧化同位素洞穴堆积物古代气候

Topic enhanced deep structured semantic models for knowledge base question answering

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Science China(Information Sciences) 2017年第11期60卷 28-42页

作者： Zhiwen XIE Zhao ZENG Guangyou ZHOU weijun wang School of Computer Central China Normal University Key Laboratory of Adolescent Cyberpsychology and Behavior Ministry of EducationCentral China Normal University

Knowledge Base Question Answering(KBQA) is a hot research topic in natural language processing(NLP). The most challenging problem in KBQA is how to understand the semantic information of natural language questions and how to bridge the semantic gap between the natural language questions and the structured fact triples in knowledge base. This paper focuses on simple questions which can be answered by a single fact triple in knowledge base. We propose a topic enhanced deep structured semantic model for KBQA. The proposed method considers the task of KBQA as a matching problem between questions and the subjects and predicates in knowledge base. And the proposed model consists of two stages to match the subjects and predicates, respectively. In the first stage, we propose a Convolutional based Topic Entity Extraction Model(CTEEM) to extract topic entities mentioned in questions. With the extracted entities, we can retrieve the relevant candidate fact triples from knowledge base and obviously decrease the amount of noising candidates. In the second stage, we employ Deep Structured Semantic Models(DSSMs) to compute the semantic relevant score between questions and predicates in the candidates. And we combine the semantic level and the lexical level scores to rank the candidates. We evaluate the proposed method on KBQA dataset released by NLPCC-ICCPOL 2016. The experimental results show that our proposed method achieves the third place among the 21 submitted ***, we also extend the DSSM by using Bi LSTM and integrate a convolutional structure on the top of Bi LSTM layers. Our experimental results show that the extension models can further improve the performance.

关键词： question answering deep learning knowledge base semantic matching topic entity

The seismogenic structures and migration characteristics of the 2021 Yangbi M6.4 Earthquake sequence in Yunnan,China

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Science China Earth Sciences 2022年第8期65卷 1522-1537页

作者： Kun YAN weijun wang Fei PENG Qincai wang Huadong KOU Aijing YUAN Institute of Geophysics China Earthquake AdministrationBeijing100081China Institute of Earthquake Forecasting China Earthquake AdministrationBeijing100036China

We constructed a more complete earthquake catalog in the 2021 Yangbi M6.4 focal area by re-scanning the continuous waveforms integrated with deep learning and template matching techniques,to explore the seismogenic structures of the Yangbi mainshock and its nucleation *** new catalog has three times the number of earthquakes than the CENC catalog,and the magnitude completeness has dropped from 1.1 to *** distribution of earthquakes indicates a broom-shaped structure consisting of several oblique secondary faults and a strike-slip main fault which strikes to 315°with 80°dipping to *** earthquakes extend along the fault strike about 27 km in width and 2-13 km at depth and have noticeable variations on seismicity in the mainshock’s north and *** with the north,the south has denser and higher magnitude aftershocks and also has a seismic gap probably weakened by the fluid at the depth range of about 5-6 *** foreshocks were mainly active in the 8-kilometer-long fault zone south of the mainshock,which show a steady drop in b-values over time and a migration pattern toward the epicenter of two steep jumps,stagnation,and then acceleration which finally triggered the *** in the north,seldom foreshock occurred,and the aftershocks were delayed triggered 3 hours after the mainshock,and sparsely scattered shallow at depth and small in *** summarize,the northern part of the Yangbi seismogenic fault is thought to be relatively locked,whereas the southern part has a weakening zone and promotes *** nucleation mechanism of the mainshock and its onset at the junction of the locked and pre-slip zones may be a combination of pre-slip and cascade triggering.

关键词： Yangbi earthquake Microseismic detection Seismogenic structure Earthquake migration Earthquake nucleation process

DNA tetrahedral nanostructures for the biomedical application and spatial orientation of biomolecules

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Bioactive Materials 2024年第3期33卷 279-310页

作者： weijun wang Mengling Lin Wenqing wang Zhifa Shen Zai-Sheng Wu Key Laboratory of Laboratory Medicine of the Ministry of Education Zhejiang Provincial Key Laboratory of Medicine GeneticsSchool of Laboratory Medicine and Life SciencesInstitute of Functional Nucleic Acids and Personalized Cancer TheranosticsWenzhou Medical UniversityWenzhou325035China Cancer Metastasis Alert and Prevention Center Fujian Provincial Key Laboratory of Cancer Metastasis Chemoprevention and ChemotherapyState Key Laboratory of Photocatalysis on Energy and EnvironmentCollege of ChemistryFuzhou UniversityFuzhou350108China College of Chemistry and Food Science Nanchang Normal UniversityNanchang330032China

DNA not only plays a vital role in nature as fundamental hereditary material for storing genetic material,but also serves as well-defined functional material,for example,building blocks for the assembly of nanoscale bio-architectures by Watson-Crick base-pairing *** the development of molecular biology,biotechnology and nanoscience,structural DNA nanotechnology has achieved numerous advances,contributing to the construction of various DNA nanostructures ranging from discrete objects to one dimensional(1D),two dimensional(2D),and three dimensional(3D)*** them,DNA tetrahedral nanoarchitecture is intensively studied because of simple 3D structure,easy design and unique properties,such as high rigidity,desirable biostability and efficient cellular uptake without auxiliary *** review summarizes the research progress in the assembly of DNA tetrahedral objects and outlines the applications in biosensing,drug delivery and targeted ***,the dependence of biological activity of biomolecules on DNA tetrahedron-mediated spatially-controlled arrangement and great potential applications are *** addition,the challenges in the design and clinic applications of DNA tetrahedron-based platforms are described,the perspectives towards biomedical applications are foreseen,and our understandings on further studies of DNA tetrahedron are provided,aiming to motivate the development of DNA nanotechnology and interdisciplinary research.

关键词： DNA tetrahedron Biomarker detection Drug delivery cancer treatment DNA nanotechnology Oriented arrangement

Applications of the Hilbert-Huang Transform for Microtremor Data Analysis Enhancement

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Journal of Earth Science 2015年第6期26卷 799-806页

作者： Lanbo Liu Robert Mehl weijun wang Qi-Fu Chen Department of Civil & Environmental Engineering University University of Connecticut Center for Integrative Geosciences University of Connecticut Institute of Earthquake Science China Earthquake Administration

In this paper we discuss the use of the Hilbert-Huang transform（HHT） to enhance the time-frequency analysis of microtremor measurements. HHT is a powerful algorithm that combines the process of empirical mode decomposition（EMD） and the Hilbert transform to compose the HilbertHuang spectrum that contains the time-frequency-energy information of the recorded signals. HHT is an adaptive algorithm and does not require the signals to be linear or stationary. HHT is advantageous for analyzing microtremor data, since observed microtremors are commonly contaminated by nonstationary transient noises close to the recording instruments. This is especially true when microtremors are measured in an urban environment. In our data processing HHT was used to（1） eliminate the unwanted short-duration transient constituents from microtremor data and use only the coherent portion of the data to carry out the widely used horizontal to vertical spectral ratio（H/V） method;（2） identify and eliminate the continuous industrial noise in certain frequency band; and（3） enhance the H/V analysis by using the Hilbert-Huang spectrum（HHS）. The efficacy of this proposed approach is demonstrated by the examples of applying it to microtremor data acquired in the metropolitan Beijing area.

关键词： Hilbert-Huang transform microtremor time-frequency HN engineering earthquake.

Failure mechanism of Mesozoic soft rock roadway in Shajihai coal mine and its surrounding rock control

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International Journal of Mining Science and Technology 2014年第6期24卷 853-858页

作者： Yuan Yue Zhu Yongjian wang weijun Yu Weijian School of Energy and Safety Engineering Hunan University of Science and Technology Hunan Provincial Key Laboratory of Safe Mining Techniques of Coal Mines Hunan University of Science and Technology

In view of the buckling failure caused by large deformation of Mesozoic soft rock roadway in Shajihai mining area, such as serious roof fall, rib spalling, floor heave, etc., based on the detail site investigation,theoretical analysis, mineral composition test, microstructure test, water-physical property test and field experiments were carried out. And we revealed the compound failure mechanism of Mesozoic soft rock roadway in Shajihai mining area, namely the molecule expansion-shear slip of weak structural plane-construction disturbance. On this basis, the coupling support technology whose core is constant resistance with large deformation bolt was proposed. The feature of this supporting technology is that a new type of structural composite material was used, which makes the supporting system not only has the ideal deformation characteristics, but also has high supporting resistance. Thus the fully release of plastic energy within surrounding rock and reasonable control of the thickness of the plastic ring were realized. Then the differential deformation between the surrounding rock and support was eliminated by the secondary coupling support of bolt–mesh–cable, and the bolt with high strength was applied in the base angle to control floor. Eventually the collaborative bearing system of surrounding rock–support was formed. Through field tests the validity and rationality of support was also verified.

关键词： Mesozoic soft rock Failure mechanism Constant resistance with large deformationsupport Control measures Collaborative bearing

Site effects on earthquake ground motion based on microtremor measurements for metropolitan Beijing

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Chinese Science Bulletin 2009年第2期54卷 280-287页

作者： CHEN QiFu LIU LanBo wang weijun ROHRBACH Eric Institute of Earthquake Science China Earthquake Administration Beijing 100036 China University of Connecticut Storrs CT 06269-2037 USA

A campaign of microtremor measurements was conducted in summer 2007 for assessing local site effects of seismic strong ground motion in metropolitan Beijing. Using the measurements from over 600 sites with approximately 1―2 km spacing covering the entire area inside Beijing’s 5th Beltway, we present the analysis results in the form of contours of the predominant resonant frequency, the thick- ness of the uppermost soft sediments, and the ground motion amplification factor. The microtremor- derived soft sediment thickness is generally in agreement with previous results based on much sparser borehole data, with the revealing of more short-wavelength undulations, which coincide with major geomorphological and neotectonic expressions in metropolitan Beijing. This study provides additional valuable information to the earthquake-resistant design of civil infrastructures and seismic hazard response in metropolitan Beijing. It also provides a feasible geophysical approaching to explore the 3-D structure beneath metropolitan cities.

关键词：基岩理论分析地脉动机制分析法北京

Parameters Identification for Extended Debye Model of XLPE Cables Based on Sparsity-Promoting Dynamic Mode Decomposition Method

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Energy Engineering 2023年第10期120卷 2433-2448页

作者： weijun wang Min Chen Hui Yin Yuan Li Guiyang Power Supply Bureau Guizhou Power Grid Co.Ltd.Guiyang550004China College of Electrical Engineering Sichuan UniversityChengdu610065China

To identify the parameters of the extended Debye model of XLPE cables,and therefore evaluate the insulation performance of the samples,the sparsity-promoting dynamicmode decomposition(SPDMD)methodwas introduced,aswell the basics and processes of its applicationwere *** amplitude vector based on polarization current was first *** on the non-zero elements of the vector,the number of branches and parameters including the coefficients and time constants of each branch of the extended Debye model were *** research on parameter identification of XLPE cables at different aging stages based on the SPDMD method was carried out to verify the practicability of the *** with the traditional differential method,the simulation and experiment indicated that the SPDMD method can effectively avoid problems such as the relaxation peak being unobvious,and possessing more accuracy during the parameter *** due to the polarization current being less affected by the measurement noise than the depolarization current,the SPDMD identification results based on the polarization current spectral line proved to be better at reflecting the response characteristics of the *** addition,the time domain polarization current test results can be converted into the frequency domain,and then used to obtain the dielectric loss factor spectrum of the *** integral of the dielectric loss factor on a frequency domain can effectively evaluate the insulation condition of the XLPE cable.

关键词： Cable insulation dielectric response sparsity-promoting dynamic mode decomposition parameter identification