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An adaptive dwell time scheduling model for phased array radar based on three-way decision

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Journal of Systems Engineering and Electronics 2020年第3期31卷 500-509页

作者： LI Bo TIAN Linyu chen daqing LIANG Shiyang School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710129China School of Engineering London South Bank UniversityLondon SE10AAUK

Real-time resource allocation is crucial for phased array radar to undertake multi-task with limited resources,such as the situation of multi-target tracking,in which targets need to be prioritized so that resources can be allocated accordingly and effectively.A three-way decision-based model is proposed for adaptive scheduling of phased radar dwell *** the model,the threat posed by a target is measured by an evaluation function,and therefore,a target is assigned to one of the three possible decision regions,i.e.,positive region,negative region,and boundary region.A different region has a various priority in terms of resource demand,and as such,a different radar resource allocation decision is applied to each region to satisfy different tracking accuracies of *** addition,the dwell time scheduling model can be further optimized by implementing a strategy for determining a proper threshold of three-way decision making to optimize the thresholds adaptively in *** advantages and the performance of the proposed model have been verified by experimental simulations with comparison to the traditional twoway decision model and the three-way decision model without threshold *** experiential results demonstrate that the performance of the proposed model has a certain advantage in detecting high threat targets.

关键词： phased array radar resource scheduling three-way decision threat assessment

Preparation and characterization of a specialized lunar regolith simulant for use in lunar low gravity simulation

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International Journal of Mining Science and Technology 2022年第1期32卷 1-15页

作者： Ruilin Li Guoqing Zhou Kang Yan Jun chen daqing chen Shangyue Cai Pin-Qiang Mo State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou 221116China School of Water Resources and Hydropower Engineering Wuhan UniversityWuhan 430072China

Lunar in-situ resource utilization(ISRU)has been put on the agenda by many *** to the special material nature and low gravity environment,the lunar regolith demonstrates significantly different behavior from terrestrial ***,the systematic understanding of its geotechnical behavior is now seriously restricted by the scarcity of lunar regolith and the difficulty in simulating lunar gravity.A new lunar regolith simulant,termed as China University of Mining and Technology Number One(CUMT-1),has been developed to recover properties of the lunar regolith and simulate the lunar gravity by adopting the recently advanced geotechnical magnetic-similitude-gravity model testing(GMMT)*** CUMT-1 simulant was prepared by reproducing the in-situ formation and fragmentation of the lunar matrix,which plays a key role in the irregular particle *** mineralogical compositions,particle morphology and gradation,specific gravity,bulk density,void ratio,shear strength,and compressibility were *** quantifying the magnetization and magnetic-similitude-gravity characteristics,an application of the cone penetration resistance under low gravity was further *** obtained results are compared to the values known for lunar regolith samples and other simulants,which demonstrates promising characteristics for use in geotechnical engineering-based and scientificbased applications,especially considering the influence of lunar gravity.

关键词： Lunar regolith CUMT-1 simulant Low gravity GMMT method ISRU

Behaviour of granular matter under gravity-induced stress gradient:A two-dimensional numerical investigation

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International Journal of Mining Science and Technology 2021年第3期31卷 439-450页

作者： Ruilin Li Guoqing Zhou Pin-Qiang Mo Matthew R.Hall Jun chen daqing chen Shangyue Cai State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China GeoEnergy Research Centre Faculty of EngineeringUniversity of NottinghamNottingham NG72RDUK School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou 221116China

Gravity is the most important load source in mining and geotechnical engineering,which causes both the stress level and stress gradient inside *** from the stress level,the influence of gravity-induced stress gradient on the behaviour of the material is still *** in-deep study on it will help to promote the understanding of material behaviour,especially for those cases related to unconventional gravity such as terrestrial ng physical modelling and extraterrestrial resource exploitation(g is the terrestrial gravitational acceleration).In this study,a high-order homogenization for granular materials is proposed at first,in which the stress gradient is drawn into the constitutive representation by adopting a representative volume element(RVE).The consolidation and shear strength behaviour of RVE are then investigated by performing numerical biaxial *** results show that all the compressibility,shear strength,shear stiffness,volumetric deformation,and critical state behaviour show a stress gradient dependence.A coupling between stress gradient,stress level,and material properties is also *** observations suggest that,besides the stress level,extra attention needs to be paid to material responses related to stress gradient during engineering practices.

关键词： Stress gradient Representative volume element Granular matter Gravitational field Discrete element method

Developing phoneme-based lip-reading sentences system for silent speech recognition

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CAAI Transactions on Intelligence Technology 2023年第1期8卷 129-138页

作者： Randa El-Bialy daqing chen Souheil Fenghour Walid Hussein Perry Xiao Omar HKaram Bo Li School of Engineering London South Bank UniversityLondonUK Faculty of Informatics and Computer Science British University in EgyptCairoEgypt School of Electronics and Informatics Northwestern Polytechnical UniversityXi'anChina

Lip-reading is a process of interpreting speech by visually analysing lip *** research in this area has shifted from simple word recognition to lip-reading sentences in the *** paper attempts to use phonemes as a classification schema for lip-reading sentences to explore an alternative schema and to enhance system *** classification schemas have been investigated,including characterbased and visemes-based *** visual front-end model of the system consists of a Spatial-Temporal(3D)convolution followed by a 2D *** utilise multi-headed attention for phoneme recognition *** the language model,a Recurrent Neural Network is *** performance of the proposed system has been testified with the BBC Lip Reading Sentences 2(LRS2)benchmark *** with the state-of-the-art approaches in lip-reading sentences,the proposed system has demonstrated an improved performance by a 10%lower word error rate on average under varying illumination ratios.

关键词： deep learning deep neural networks lip-reading phoneme-based lip-reading spatial-temporal convolution,transformers

Cloning and Expression Analysis of a Prion Protein Encoding Gene in Guppy (Poecilia reticulata)

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Journal of Ocean University of China 2008年第4期7卷 425-431页

作者： WU Suihan WEI Qiwei YANG GuanDin WANG Dengqiang ZOU Guiwei chen daqing College of Marine Life Sciences Ocean Universin of China Qingdao 266003 P R. China Yangtze River Fisheries Research Institute Chinese Academy of Fishery Jingzhou 434000 P R. China

The full length cDNA of a prion protein (PrP) encoding gene of guppy (Poecilia reticulata) and the corresponding ge-nomic DNA were cloned. The cDNA was 2245 bp in length and contained an open reading frame (ORF) of 1545 bp encoding a pro-tein of 515 amino acids,which held all typical structural characteristics of the functional PrP. The cloned genomic DNA fragment corresponding to the cDNA was 3720 bp in length,consisting of 2 introns and 2 exons. The 5’ untranslated region of cDNA origi-nated from the 2 exons,while the ORF originated from the second exon. Although the gene was transcribed in diverse tissues in-cluding brain,eye,liver,intestine,muscle and tail,its transcript was most abundant in the brain. In addition,the transcription of the gene was enhanced by 5 salinity,implying that it was associated with the response of guppy to saline stress.

关键词： guppy Poecilia reticulata prion protein gene expression analysis

A Preliminary Study on Mechanisms of Well Water Temperature Responses Based on the Modes of Stress Loading

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Earthquake Research in China 2011年第4期25卷 477-485页

作者： chen daqing Wan Yongfang Earthquake Administration of Guangdong Province Guangzhou 510070 China

Based on the studies of the predecessors, and contrasting the modes of stress loading with water level and water temperature response characteristics of a well-aquifer system, this paper draws a preliminary conclusion on the mechanisms of water temperature responses in a well caused by three modes of stress loading, i.e. gas escape, heat dispersion and cold water penetration mechanisms for elastic seismic wave stress loading; the fracture seepage mechanism for seismic wave stress loading and the hydrodynamic mechanism for earth tide stress loading and stress-dissipative heat mechanism for long period slow stress loading in the earthquake preparation stage. This paper illustrates the typical observation examples for each mode of stress loading and makes a preliminary study on their mechanisms.

关键词： Water temperature in well Stress loading Response mechanism

A Study on Tidal Force Triggering of the Wenchuan M_S8.0 Earthquake and Its Strong Aftershocks

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Earthquake Research in China 2012年第1期26卷 87-96页

作者： chen daqing Yang Maling Liu Jin Earthquake Administration of Guangdong Province Guangzhou 510070China

By calculating the azimuth, phase angle and change rate of tidal force, and contrasting their rupture types, we find that in 6 of 11 reverse faulting earthquakes, the angles between the direction of the horizontal tidal force and compressive principal stress are within 33°, the vertical phase angles of all 8 strike-slip earthquakes are in the upward peak section and the vertical phase angles of two extensional normal faulting earthquakes are in the downward peak section. According to the above statistics, the mechanism of tidal force triggering of the Wenchnan Ms8. 0 Earthquake and its strong aftershocks is discussed.

关键词： Wenchuan earthquake Strong aftershocks Tidal force The triggeringmechanism

Implementing the Standardized Usage Statistics Harvesting Initiative (SUSHI) protocol

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Journal of Library Science in China 2018年 171-173页

作者： chen daqing YE Lan DING Pei 不详

The Standardized Usage Statistics Harvesting Initiative(SUSHI)is a protocol developed in response to the need in libraries to collect COUNTER compliant usage statistics *** years have passed since SUSHI became a NISO ... 详细信息

关键词： Implementing Standardized Usage Statistics Harvesting Initiative SUSHI protocol

Co-seismic Water Level and Temperature Responses of Some Wells to Far-Field Strong Earthquakes and Their Mechanisms

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Earthquake Research in China 2007年第3期21卷 333-344页

作者： chen daqing Liu Yaowei Yang Xuanhui Liu Yongming Earthquake Administration of Guangdong Province Guangzhou 510070 China Institute of Crustal Dynamics China Earthquake Administration Beijing 100085 China

The observation of water temperature in deep wells has been carried out for more than 20 years in ***,study on the mechanism of water temperature response to earthquakes is *** the study of the co-seismic response characteristics of water level and temperature in 121 wells within the China subsurface fluid monitoring network at the time of the December 26,2004,M-S8.7 Indonesia earthquake,we found regular response characteristics,that is,when the water level in a deep well oscillates,the water temperature in the same well will mostly experience a cycle from dropping to restoration at the same *** process will continue for dozens of minutes to several *** order to confirm the observed phenomenon,we collected the digital water level and temperature observation data for 39 far-field strong earthquakes from the Tangshan well in Hebei Province(with the data set beginning in 2001).The same response characteristics were *** on the analysis of the influencing factors that may cause the water temperature drop,the authors suggest the gas escape mechanism for co-seismic water temperature drop and posit two main factors that influence the water temperature drop during the process of gas ***,the authors provide a rational explanation of some observed phenomena based on the mechanism.

关键词： Water level oscillation Water temperature drop Co-seismic response Gas escape