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Study on Recognition Method of Similar Weather Scenes in Terminal Area

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Computer Systems Science & Engineering 2023年第2期44卷 1171-1185页

作者： Ligang Yuan Jiazhi Jin Yan Xu Ningning zhang bing zhang College of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing211106China School of Aerospace Transport and ManufacturingCranfield UniversityBedfordMK430ALUnited Kingdom Travelsky Technology Limited Beijing100010China College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing211106China

Weather is a key factor affecting the control of air trafﬁ*** recognition and classiﬁcation of similar weather scenes in the terminal area is helpful for rapid decision-making in air trafﬁcﬂow *** researches mostly use traditional machine learning methods to extract features of weather scenes,and clustering algorithms to divide similar *** by the excellent performance of deep learning in image recognition,this paper proposes a terminal area similar weather scene classiﬁcation method based on improved deep convolution embedded clustering(IDCEC),which uses the com-bination of the encoding layer and the decoding layer to reduce the dimensionality of the weather image,retaining useful information to the greatest extent,and then uses the combination of the pre-trained encoding layer and the clustering layer to train the clustering model of the similar scenes in the terminal ***,term-inal area of Guangzhou Airport is selected as the research object,the method pro-posed in this article is used to classify historical weather data in similar scenes,and the performance is compared with other state-of-the-art *** experi-mental results show that the proposed IDCEC method can identify similar scenes more accurately based on the spatial distribution characteristics and severity of weather;at the same time,compared with the actualﬂight volume in the Guangz-hou terminal area,IDCEC's recognition results of similar weather scenes are con-sistent with the recognition of experts in theﬁeld.

关键词： Air trafﬁc terminal area similar scenes deep embedding clustering

Multi-band optical variability of BL Lac object OQ 530

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Research in Astronomy and Astrophysics 2010年第7期10卷 653-662页

作者： bing-Kai zhang Ben-Zhong Dai Li zhang Zhen Cao Department of Physics Fuyang Normal College Fuyang 236041 China Department of Physics Yunnan University Kunming 650091 China Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

Historical optical data are combined on the BL Lac object OQ 530. Verifying the existence of correlations among the flux variations in different bands serves as an important tool to investigate emission processes. To examine the possible existence of a lag between variations in different optical bands from this source, a statistical analysis is performed through the discrete correlation function （DCF） method and the z-transformed discrete correlation function （ZDCF） method. Monte Carlo simulations called ＂flux redistribution/random subset selection＂（FR/RSS） are performed to obtain statistically meaningful values for the cross-correlation time lags and their related uncertainties. The analysis confirms that the variations in different optical light curves are strongly correlated, with zero-lag within the errors. Long term variability of color indexes is also analyzed. The result suggests a strong correlation between color index and brightness. A clear bluer-when-brighter chromatism is found, in the sense that the spectrum steepens as the brightness decreases.

关键词： BL Lacs general -- BL Lacs individual (OQ 530)

Resource Allocation Algorithm Based on PSO-GA for Multi-User OFDM System

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Journal of Electronic Science and Technology 2015年第1期13卷 68-72页

作者： Hao-Ye zhang Jin-Ping Mei Shi-bing zhang Nantong Branch China Mobile Group Jiangsu Company Limited School of Electronics and Information Nantong University

In order to minimize the transmitted power in the multi-user orthogonal frequency division multiplexing（OFDM） system, a scheme combining the improved particle swarm optimization（POS） algorithm with genetic algorithm（GA） is proposed to optimize the sub-carriers and bits allocation. In the algorithm, a random velocity between the maximum and minimum particle velocity is used as the updating velocity instead of maximum or minimum velocity when the updated particle velocity is higher than the maximum particle velocity or lower than the minimum particle velocity. Then, the convergence population is used as the initial population of the genetic algorithm to optimize the subcarriers and bits allocation further. Simulation results show that the transmitted power of the proposed algorithm is about 2 d B to 10 d B lower than that of the genetic algorithm, particle swarm optimization algorithm, and zhang＇s algorithm.

关键词： Bit allocation orthogonal frequency division multiplexing particle swarm optimization algorithm with genetic algorithm sub-carri

Experimental and theoretical study on the dynamic effective stress of loaded gassy coal during gas release

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International Journal of Mining Science and Technology 2023年第3期33卷 339-349页

作者： bing zhang Hanpeng Wang Peng Wang Guofeng Yu Shitan Gu School of Qilu Transportation Shandong UniversityJinan 250061China Geotechnical and Structural Engineering Research Center Shandong UniversityJinan 250061China Coal Mining National Engineering Technology Research Institute Huainan 232001China State Key Laboratory of Mining Disaster Prevention and Control Co-Founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and TechnologyQingdao 266590China

In the process of mining coalbed methane(CBM),an unsteady state often arises due to the rapid extraction,release and pressure relief of *** this case,the effective stress of coal changes dynamically,affecting the stability of the gassy coal *** this paper,gas release tests of gassy coal under conventional triaxial compression were performed,and the dynamic effective stress(DES)during gas release was obtained indirectly based on a constitutive equation and deformation of *** results show that the maximum increases in DES caused by the release of free gas and adsorbed gas under the stress of 1.1 MPa were 0.811 and 5.418 MPa,respectively,which seriously affected the stress state of the *** the gas release,the free gas pressure and the adsorbed gas volume were the parameters that directly affected the DES and showed a positive linear relationship with the DES with an intercept of *** DES of the coal sample increased exponentially with time,which was determined by the contents of free and adsorbed *** on the experimental results and theoretical analysis,an effective stress model was obtained for loaded gassy coal during gas *** results of verification indicated accuracy greater than 99%.

关键词： Gassy coal Dynamic effective stress Gas release Gas-solid coupling Mathematical model

The roles of intraflagellar transport (IFT) protein 25 in mammalian signaling transduction and flagellogenesis

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Asian Journal of Andrology 2022年第3期24卷 238-242页

作者： Yong-Hong Man Isabella Warmbrunn Ling zhang Zhi-bing zhang Department of Occupational and Environmental Medicine School of Public HealthWuhan University of Science and TechnologyWuhan 430065China Center of Scientific Research and Experiment Nanyang Medical CollegeNanyang 473006China Department of Physiology Wayne State University School of MedicineDetroitMI 48201USA Department of Obstetrics and Gynecology Wayne State University School of MedicineDetroitMI 48201USA

Cilium,an organelle with a unique proteome and organization,protruding from the cell surface,generally serves as a force generator and signaling *** ciliogenesis,ciliary proteins are synthesized in cytoplasm and transported into cilia by intraflagellar transport(IFT)particles,where the inner counterparts undergo reverse *** homeostasis of IFT plays a key role in cilial structure assembly and signaling *** progress has been made on the mechanisms and functions of IFT;however,recent studies have revealed the involvement of IFT particle subunits in organogenesis and *** this review,we discuss new concepts concerning the molecular functions of IFT protein IFT25 and how its interactions with other IFT particle subunits are involved in mammalian development and fertility.

关键词： IFT25 cilium hedgehog signaling intraflagellar transport spermatogenesis

A new kernel method for hyperspectral image feature extraction

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Geo-Spatial Information Science 2017年第4期20卷 309-318页

作者： Bin Zhao Lianru Gao Wenzhi Liao bing zhang Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences Beijing China University of Chinese Academy of Sciences Ringgold Standard Institution Beijing China Department of Telecommunications and Information Processing Ghent University Ghent Belgium

Hyperspectral image provides abundant spectral information for remote discrimination of subtle differences in ground ***,the increasing spectral dimensions,as well as the information redundancy,make the analysis and interpretation of hyperspectral images a *** extraction is a very important step for hyperspectral image *** extraction methods aim at reducing the dimension of data,while preserving as much information as ***,nonlinear feature extraction methods (*** minimum noise fraction (KMNF) transformation) have been reported to benefit many applications of hyperspectral remote sensing,due to their good preservation of high-order structures of the original ***,conventional KMNF or its extensions have some limitations on noise fraction estimation during the feature extraction,and this leads to poor performances for *** paper proposes a novel nonlinear feature extraction method for hyperspectral *** of estimating noise fraction by the nearest neighborhood information (within a sliding window),the proposed method explores the use of image *** approach benefits both noise fraction estimation and information preservation,and enables a significant improvement for *** results on two real hyperspectral images demonstrate the efficiency of the proposed *** to conventional KMNF,the improvements of the method on two hyperspectral image classification are 8 and 11％.This nonlinear feature extraction method can be also applied to other disciplines where high-dimensional data analysis is required.

关键词： Hyperspectral image dimensionality reduction feature extraction image segmentation kernel method

SolidEarth： a new Digital Earth system for the modeling and visualization of the whole Earth space

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Frontiers of Earth Science 2014年第4期8卷 524-539页

作者： Liangfeng ZHU Jianzhong SUN Changling LI bing zhang Key Laboratory of Geographic Information Science for Ministry of Education East China Normal University Shanghai 200241 China Center for Earth System Science Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201203 China School of Environmental Science and Spatial Informatics China University of Mining and Technology Xuzhou 221008 China College of Geomatics Engineering Nanjing University of Technology Nanjing 211816 China.

Although many of the first-generation Digital Earth systems have proven to be quite useful for the modeling and visualization of geospatial objects relevant to the Earth＇s surface and near-surface, they were not designed for the purpose of modeling and application in geological or atmospheric space. There is a pressing need for a new Digital Earth system that can process geospatial information with full dimensionality. In this paper, we present a new Digital Earth system, termed SolidEarth, as an alternative virtual globe for the modeling and visualization of the whole Earth space including its surface, interior, and exterior space. SolidEarth consists of four functional components： modeling in geographical space, modeling in geological space, modeling in atmo- spheric space, and, integrated visualization and analysis. SolidEarth has a comprehensive treatment to the third spatial dimension and a series of sophisticated 3D spatial analysis functions. Therefore, it is well-suited to the volumetric representation and visual analysis of the inner/ outer spheres in Earth space. SolidEarth can be used in a number of fields such as geoscience research and education, the construction of Digital Earth applications, and other professional practices of Earth science.

关键词： Digital Earth Earth space full dimensionality,visualization

A negative selection algorithm based on hierarchical clustering of self set

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Science China(Information Sciences) 2013年第8期56卷 203-215页

作者： CHEN Wen LI Tao LIU XiaoJie zhang bing College of Computer Science Sichuan University National Computer Network Emergency Response Technical Team Coordination Center of China

Negative selection algorithm(NSA) is an important method of generating artificial immune ***,the traditional NSAs aim at eliminating the self-recognized invalid detectors,by matching candidate detectors with the whole self *** matching process results in extremely low generation efficiency and significantly limits the application of *** this paper,an improved NSA called CB-RNSA,which is based on the hierarchical clustering of self set,is *** CB-RNSA,the self data is first preprocessed by hierarchical clustering,and then replaced by the self cluster centers to match with candidate detectors in order to reduce the distance calculation *** the detector generation process,the candidate detectors are restricted to the lower coverage space to reduce the detector *** the paper,probabilistic analysis is performed on non-self coverage of ***,termination condition of the detector generation procedure in CB-RNSA is *** is more reasonable than that of traditional NSAs,which are based on predefined detector *** theoretical analysis shows the time complexity of CB-RNSA is irrelevant to the self set ***,the difficult problem,in which the detector training cost is exponentially related to the size of self set in traditional NSAs,is resolved,and the efficiency of the detector generation under a big self set is also *** experimental results show that:under the same data set and expected coverage,the detection rate of CB-RNSA is higher than that of the classic RNSA and V-detector algorithms by 12.3% and 7.4% ***,the false alarm rate is lower by 8.5% and 4.9% respectively,and the time cost of CB-RNSA is lower by 67.6% and 75.7% respectively.

关键词： artificial immune system negative selection algorithm detector cluster

The influence of main ecological and environmental factors on the energy budget of Schlegel＇ s black rockfish Sebastes schlegeli

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Acta Oceanologica Sinica 2007年第3期26卷 90-100页

作者： SUN Yao ZHENG bing zhang Bo TANG Qisheng Key Laboratory for Sustainable Utilization of Marine Fisheries Resources of Ministry of Agriculture Yellow Sea Fisheries Research Institute Chinese Academy of Fisheries Sciences Qingdao 266071 China

In the Maidao Ecological Laboratory of the Huanghai Sea Fisheries Research Institute in 1998 ~ 2000, the continuous flow-through method was adopted to determine the energy budget components and models of Schlegel＇ s black rockfish under different ecological and environmental factors, such as temperature, food species, body mass and feeding level, etc. The body mass of test fish ranged from 21.2 to 224.5 g. The specific growth rate tended to invert ＂U＂ change with temperature increase. The ecological conversion efficiency showed the same trend as temperature and feeding level rise. Only the specific growth rate tended to decelerate the increment with the rise of feeding level. From the above quantitative relationships, the maximum and optimal growth temper- atures could be obtained as 17.5 and 16.2 ℃, and the maintenance feeding rate and optimum feeding rate as 0.8% and 4. 1% of the body mass. The specific growth rate and ecological conversion coefficient showed a decelerating decrease trend with body mass increment. The small-sized fish food was more advantageous to the feeding level increase in comparison with the small-sized shrimp food, which led to the increase of growth, metabolism and excretion, but had no significant influence on the ecological conversion coefficient. All of temperature, feeding level, body mass and food species can obviously change the energy budget models. The assigning rate of growth energy tended to change along the invert ＂U＂ curve with the increase of temperature and feeding level, and decrease with the body mass increase, but the assigning rates of metabolism energy and excretion energy were quite reverse. These relationships could be quantitatively described as quadratic or power function curve. If the above relationships proved true to other marine fish, the establishment of energy budget model of the same fish under different conditions can be largely simplified.

关键词： influence ecological and environmental factors energy budget Sebastes schlegeli