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Object-oriented GIS technology and mine geo-dynamic division information management
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作者 LI Sheng, FENG Fu, XU Xue-feng (Liaoning Technical University, Fuxin 123000, China) 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期42-44,共3页
Object-oriented methodology was expected to revolutionize GIS design and development, making it easier and faster to design, through a common approach to conceptual modelling, database design, programming languages an... Object-oriented methodology was expected to revolutionize GIS design and development, making it easier and faster to design, through a common approach to conceptual modelling, database design, programming languages and user interface tools. In addition, an object-oriented model provides some useful tools for data abstraction and data structuring, which augment the conventional tools and overcome some deficiencies inherent to the traditional relational model. The principles of object-oriented modelling applied to geographic data were put forward, and the concepts of object-oriented paradigm and characteristics of spatial data management were proposed in order to argument their compatibility. 展开更多
关键词 OBJECT-ORIENTED GIS geo-dynamic division
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Geological division of gas in the Pingdingshan mine area based on its tectonic dynamics characteristics
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作者 Lei Dongji Li Hui Meng Hui 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第5期827-833,共7页
In this paper,we used tectonic dynamics theories to study the tectonic evolution characteristics of the Pingdingshan mine area,and analyzed the impact of tectonic progressive control on gas occurrence.The study result... In this paper,we used tectonic dynamics theories to study the tectonic evolution characteristics of the Pingdingshan mine area,and analyzed the impact of tectonic progressive control on gas occurrence.The study results are as follows:the Pingdingshan mine area has been mainly controlled by multiple squeezing and shearing actions of the Qinling orogenic belt since early and middle Yanshan,forming the tectonic control characteristics of master control in two directions,namely NWW trending and NNE trending;the NWW trending structure is dominated by squeezing and shearing,while the NNE trending structure is dominated by tension.Progressively controlled by the structure,the gas occurrence presents partition and zonation,i.e.compared with the western structure,the eastern NWW-NW trending structure of the mine area is more highly developed,resulting in the mine area gas occurrence distribution characteristics are distinct in the east while indistinct in the west.Based on this,the mine area can be divided into the following two geological dynamic areas:the western half of mine area,namely the Guodishan fault control area,where the NW-SE trending synchronous tension action suffered by the northeast side(footwall) is relatively strong,and compared with the southwest side(hanging wall),its coal and gas outburst seriousness is weak;and the eastern half of mine area,namely the NWW-NW thrust nappe fracture fold control area,which is a serious area of coal and gas outburst,in particular the axial area of the Likou syncline is the intersection compound and combination position of the NW and NE trending structures,a tectonic concentrated area,and the gas pressure and content here are the largest. 展开更多
关键词 Tectonic evolution Tectonic environment dynamic division Tectonic division
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Time-sequential color code division multiplexing holographic display with metasurface 被引量:14
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作者 Xin Li Qinmiao Chen +4 位作者 Xue Zhang Ruizhe Zhao Shumin Xiao Yongtian Wang Lingling Huang 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第8期8-16,共9页
Color metasurface holograms are powerful and versatile platforms for modulating the amplitude,phase,polarization,and other properties of light at multiple operating wavelengths.However,the current color metasurface ho... Color metasurface holograms are powerful and versatile platforms for modulating the amplitude,phase,polarization,and other properties of light at multiple operating wavelengths.However,the current color metasurface holography can only realize static manipulation.In this study,we propose and demonstrate a multiplexing metasurface technique combined with multiwavelength code-division multiplexing(CDM)to realize dynamic manipulation.Multicolor code references are utilized to record information within a single metasurface and increase the information capacity and security for anticracks.A total of 48 monochrome images consisting of pure color characters and multilevel color video frames were reconstructed in dual polarization channels of the birefringent metasurface to exhibit high information density,and a video was displayed via sequential illumination of the corresponding code patterns to verify the ability of dynamic manipulation.Our approach demonstrates significant application potential in optical data storage,optical encryption,multiwavelengthversatile diffractive optical elements,and stimulated emission depletion microscopy. 展开更多
关键词 metasurface color holography dynamic display code division multiplexing
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Modeling Daily Average Temperatures in a Coastal Site of Central Africa: An Analysis of Seasonal Divisions
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作者 Jean-Pierre Bell Esther C. Modi-Mbog +1 位作者 Nicodeme Djiedeu Laurent Nana 《Atmospheric and Climate Sciences》 2023年第3期341-352,共12页
The seasonality and day-to-day variation of near-surface temperature patterns can greatly control nearly all physical and biological processes though temperature predictions at such scales remain challenging. This pap... The seasonality and day-to-day variation of near-surface temperature patterns can greatly control nearly all physical and biological processes though temperature predictions at such scales remain challenging. This paper implements a simple analytical approach in order to generate daily average temperatures which implicitly accounts for surface heating and drivers through a comprehensive representation of station-based temperature records on a universal standard calendar propagated by the earth’s dynamics features. The modeled and observed pattern of daily temperatures exhibits a close agreement with the level of strength agreement exceeding 0.56. The extreme high and low values of the observed temperature patterns are equally well captured although model underestimates the probability of temperatures around the two modal peaks (~25.6℃ and 27.5℃). Additionally, a theoretical thermal-based division led to the identification of six seasons, including two hot and cold periods along with two pairs of mixed hot-cold. The theoretical division proposed here appears to be a good approximation for the understanding of rainfall seasonality in this area. 展开更多
关键词 Daily Temperature Estimates Earth’s dynamics Seasonal divisions
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Quantitative division of succession and spatial patterns among different stand developmental stages in Changbai Mountains 被引量:1
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作者 GONG Zhi-wen KANG Xin-gang GU Li 《Journal of Mountain Science》 SCIE CSCD 2019年第9期2063-2078,共16页
Broadleaf-Korean pine forests exhibit high species richness and distinctive species composition, which are currently becoming more dominant among natural forests in Changbai Mountains of northeastern China. Understand... Broadleaf-Korean pine forests exhibit high species richness and distinctive species composition, which are currently becoming more dominant among natural forests in Changbai Mountains of northeastern China. Understanding the ecological process of restored vegetation is quite important for ecosystem reconstruction. Distinguishing stand development stages and analyzing the dynamic spatial patterns could provide insights into significant community coexistence mechanisms. In the present study, eight permanent study areas were established according to the substituting space for time method in Changbai Mountains of north-eastern China. The optimal division method was used to quantify the successional series into different stand development stages, and the point pattern analysis method(L(r) function) was used to analyse the dynamic changes in spatial patterns and interspecific associations. Our results suggested that:(1) The stand development process was divided into five stages: the first three stages were poplar-birch secondary forests in different stages of recovery, the fourth stage was thespruce-fir mixed forest, and the last stage was the primary broadleaf-Korean pine forest;(2) The spatial pattern showed an aggregated distribution at a small scale and changed to a random distribution as the scale increased in poplar-birch secondary forests, but the spatial pattern appeared to be randomly distributed in spruce-fir mixed forest and broadleafKorean pine forest;(3) The interspecific associations between pioneer species and climax species changed from negative to positive among the different stand stages, and environmental resources were shared among these species. Interspecific differences in shade tolerance among the tree species were key determinants of forest dynamics and structure. Our study is vital to the understanding of the forest development;thus, the spatial change features should receive greater attention when forest management is being planned and restoration strategies are being developed for the Changbai Mountains. 展开更多
关键词 dynamic spatial patterns INTERSPECIFIC association Optimal division method STAND DEVELOPMENTAL STAGES Space for time substitution
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Control of period-one oscillation for all-optical clock division and clock recovery by optical pulse injection driven semiconductor laser 被引量:1
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作者 李静霞 张明江 +1 位作者 牛生晓 王云才 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第12期4516-4522,共7页
The period-one oscillation produced by an external optical pulse injection driven semiconductor laser is applied to clock recovery and frequency division. By adjusting the repetition rate or injection power of the ext... The period-one oscillation produced by an external optical pulse injection driven semiconductor laser is applied to clock recovery and frequency division. By adjusting the repetition rate or injection power of the external injection optical pulses to lock the different harmonic frequencies of the period-one state, the clock recovery and the frequency division (the second and third frequency divisions) are achieved experimentally. In addition, in frequency locking ranges of 2 GHz and 1.9 GHz, the second and third frequency divisions are obtained with the phase noise lower than 100 dBc/Hz, respectively. Our experimental results are consistent well with the numerical simulations. 展开更多
关键词 clock division clock recovery optical pulses injection nonlinear dynamics
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Dynamic Resource Allocation in TDD-Based Heterogeneous Cloud Radio Access Networks 被引量:2
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作者 Zhi Yu Ke Wang +2 位作者 Hong Ji Xi Li Heli Zhang 《China Communications》 SCIE CSCD 2016年第6期1-11,共11页
To fulfill the explosive growth of network capacity, fifth generation(5G) standard has captured the attention and imagination of researchers and engineers around the world. In particular, heterogeneous cloud radio acc... To fulfill the explosive growth of network capacity, fifth generation(5G) standard has captured the attention and imagination of researchers and engineers around the world. In particular, heterogeneous cloud radio access network(H-CRAN), as a promising network paradigm in 5G system, is a hot research topic in recent years. However, the densely deployment of RRHs in H-CRAN leads to downlink/uplink traffic asymmetry and severe inter-cell interference which could seriously impair the network throughput and resource utilization. To simultaneously solve these two problems, we proposed a dynamic resource allocation(DRA) scheme for H-CRAN in TDD mode. Firstly, we design a clustering algorithm to group the RRHs into different sets. Secondly, we adopt coordinated multipoint technology to eliminate the interference in each set. Finally, we formulate the joint frame structure, power and subcarrier selection problem as a mixed strategy noncooperative game. The simulation results are presented to validate the effectiveness of our proposed algorithm by compared with the existing work. 展开更多
关键词 heterogeneous cloud radio accessnetworks dynamic time division duplex resource allocation coordinated multipoint
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DYNAMIC CHARACTERISTICS OF PRESENT PRODUCTIVITY FOR CULTIVATED LAND IN THE FARNMING-PASTORAL ZONE OF INNER MONGOLIA 被引量:1
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作者 Wang Jing ’ai(Department of Resources and Environmental Science Beijing Normal University, Beijing 100875People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1995年第2期21-29,共9页
In this article, the distribution of cultivated land, the changes ofcultivated land productivity, and regional differentiation of the Change forpresent productivity in the Farming-Pastoral Zone, Inner Mongolia aredis... In this article, the distribution of cultivated land, the changes ofcultivated land productivity, and regional differentiation of the Change forpresent productivity in the Farming-Pastoral Zone, Inner Mongolia arediscussed. Then, the close relationship between dynamic characterlsticsdivision and atmospheric circulation systems is revealed. Finally, based ondynamic characteristics, four regions are divided, including thenortheastem area, the eastern area, the western area, and the middle area. 展开更多
关键词 Farming-Pastoral Zone present productivity cultivated land dynamic characteristics division
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Modeling and Dynamic Analysis in Software Systems Based on Complex Networks
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作者 Gao Yang Peng Yong +2 位作者 Xie Feng Dai Zhonghua Xu Guo'ai 《China Communications》 SCIE CSCD 2012年第12期137-143,共7页
A software network model with multiple links is constructed on the basis of a dynamical model of a general complex network with mukiple links. The principle of network division of multiple links is introduced. Followi... A software network model with multiple links is constructed on the basis of a dynamical model of a general complex network with mukiple links. The principle of network division of multiple links is introduced. Following these principles, the software network model is decomposed into three types of subnets and different relationships between classes are revealed. Then, the dynamic analysis of software networks is presented. A sufficient condition for the stability of general complex networks is obtained followed by that of software networks. Finally, the dynamics of an open-source software system is analyzed, and their simulations are provided to demonstrate the effectiveness of the presented model. 展开更多
关键词 software networks multiple links network division subnets dynamic analysis
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Analysis of faults stability with dynamic phenomena in the mice based on slide criterion and in-situ stress measurement
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作者 宋卫华 王宇峰 王新华 《Journal of Coal Science & Engineering(China)》 2008年第4期640-643,共4页
For the study on the relationshl'p between the dynamic phenomena in the mining such as mine earthquakes, outburst and faults slide, firstly, double shear friction experiments of sandstone were made, and its slide cri... For the study on the relationshl'p between the dynamic phenomena in the mining such as mine earthquakes, outburst and faults slide, firstly, double shear friction experiments of sandstone were made, and its slide criterion was suggested considering the viewing of engineering. Secondly, in order to study the stability of underground rock and zone of tectonic stress field, based on the analysis on distribution characteristic of initial rock stress measurements, the geology structural model was built and tectonic stress field was made a back-analysis by applying finite element method. The calculating results fit with the analysis result of earthquakes mechanism and the distribution characteristic of the measurements. The high stress regional centers station locates discontinuous zone of I level faults and is corresponding to underground earthquakes scene. From then it is certain that tectonic stress is the major origin and necessary condition of mine earthquakes. The instability slide of the faults is the main manifest and the mining activity is the leading factor. Beipiao fault has a dominate effect on other sub faults and tectonic stress area and is dynamical fountain of dynamic phenomena in the Beipiao Mines. 展开更多
关键词 dynamic phenomena in the mine double shear friction experiment tectonic stress field faults slide geo-dynamic division
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Utility-optimization dynamic subcarrier allocation algorithm for SC-FDMA systems
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作者 李一兵 Zhang Xu Ye Fang 《High Technology Letters》 EI CAS 2014年第1期1-8,共8页
Two utility-optimization dynamic subcarrier allocation(DSA) algorithms are designed for single carrier frequency division multiple access system(SC-FDMA).The two proposed algorithms aim to support diverse transmission... Two utility-optimization dynamic subcarrier allocation(DSA) algorithms are designed for single carrier frequency division multiple access system(SC-FDMA).The two proposed algorithms aim to support diverse transmission capacity requirements in wireless networks,which consider both the channel state information(CSI) and the capacity requirements of each user by setting appropriate utility functions.Simulation results show that with considerable lower computational complexity,the first utility-optimization algorithm can meet the system capacity requirements of each user effectively.However,the rate-sum capacity performance is poor.Furthermore,the second proposed utility-optimization algorithm can contribute a better trade-off between system rate-sum capacity requirement and the capacity requirements of each user by introducing the signal to noise ratio(SNR) information to the utility function based on the first utility-optimization algorithm,which can improve the user requirements processing capability as well as achieve a better sum-rate capacity. 展开更多
关键词 single carrier frequency division multiple access (SC-FDMA) dynamic subcarri-er allocation (DSA) utility function transmission capacity requirements utility-optimization algo-rithm greedy algorithm proportional fair algorithm
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井下断层活动的定量监测及其对冲击地压的影响研究 被引量:1
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作者 荣海 魏世龙 +6 位作者 张宏伟 杨岁寒 汤进宝 陈林林 钱红亮 王雅迪 付兴 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第2期10-22,共13页
为建立断层活动与冲击地压之间的定量关系,实现煤矿冲击地压有效防控。通过理论分析义马矿区地质构造环境,以及耿村煤矿13200工作面与断层影响带的相对位置关系,研究了断裂构造对冲击地压的宏观控制作用。计算了井田构造应力并进行了构... 为建立断层活动与冲击地压之间的定量关系,实现煤矿冲击地压有效防控。通过理论分析义马矿区地质构造环境,以及耿村煤矿13200工作面与断层影响带的相对位置关系,研究了断裂构造对冲击地压的宏观控制作用。计算了井田构造应力并进行了构造应力区划分,分析了构造应力分区对冲击地压的控制作用。提出了井下断层活动性的定量监测方法,构建了“震源区煤岩体与动力核区尺度等量,震源能量随传递距离逐渐衰减”的模型,建立了大能量微震事件与断层活动的关系,确定了断层活动性对冲击地压的影响。研究结果表明:义马煤田内相对复杂的逆冲推覆构造体系,构成了义马矿区冲击地压的地质构造背景条件。F_(16)断层的影响带范围为7000~7600 m,13200工作面全部处于F_(16)断层的影响带内,在开采活动的影响下进一步增大了冲击地压的发生危险。Ⅰ-2断裂、Ⅲ-4断裂和Ⅳ-7断裂等控制的区域是冲击地压和大能量微震事件显现的主要区域,且冲击地压和大能量微震事件大多位于应力梯度区范围内。在大能量微震事件孕育和发生期间,F_(16)断层位移分别增长50 mm和45 mm;大能量微震事件发生前,断层活动拉力的增幅均相对最高,分别为2.58 kN和2.93 kN,断层位移量的快速增加和较高的应力增幅构成了大能量微震事件的主要能量来源。表明大能量微震事件和冲击地压的发生均与断层的活动联系紧密。井下断层的实际定量监测方法可以广泛应用于矿井冲击地压预测与防控的指导工作中。 展开更多
关键词 冲击地压 大能量微震 断层 地质动力区划 构造应力分区 断层活动性定量监测 能量反演
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基于PCA-ShapeDTW-QWGRU的分布式光伏集群短期功率预测
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作者 欧阳静 秦龙 +3 位作者 王坚锋 尹康 褚礼东 潘国兵 《太阳能学报》 EI CAS CSCD 北大核心 2024年第5期458-467,共10页
针对分布式光伏短期功率预测建立基于主成分分析、改进的动态时间规整算法与量子加权门控循环单元(PCAShapeDTW-QWGRU)的集群功率预测模型。针对集群划分不够精细、光伏电站数据蕴含的信息难以捕捉的问题,提出基于主成分分析结合密度聚... 针对分布式光伏短期功率预测建立基于主成分分析、改进的动态时间规整算法与量子加权门控循环单元(PCAShapeDTW-QWGRU)的集群功率预测模型。针对集群划分不够精细、光伏电站数据蕴含的信息难以捕捉的问题,提出基于主成分分析结合密度聚类算法(PCA-OPTICS)的集群划分方法;针对目前选取代表电站与集群相似性较低的问题,提出基于改进的动态时间规整算法(ShapeDTW)的代表电站的选取方法,利用ShapeDTW度量相似性距离,选取最小值作为代表电站,并利用基于均方根传播梯度下降法优化的量子加权门控循环单元(RMSprop-QWGRU)模型进行预测;为了解决代表电站与集群功率的变换系数转换差异较大的问题,采用实时变换系数对代表电站进行集群功率值预测计算。实验结果表明,所提方法能有效提升光伏集群功率预测的精度。 展开更多
关键词 光伏功率预测 集群划分 主成分分析 动态时间规整 量子加权门控循环单元
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一种可见光网络的入网与网络维护设计
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作者 贾佳 黄娅 +2 位作者 陈默 周云龙 楼韬 《光通信技术》 北大核心 2024年第5期30-34,共5页
为了简单有效地提升室内可见光网络有限带宽资源分配性能,设计了一种基于时分多址(TDMA)机制的入网与网络维护方法,详细描述了用户竞争入网流程和网络维护机制。通过设计具体的帧结构,分析了用户入网概率。实验结果表明:提入网与网络维... 为了简单有效地提升室内可见光网络有限带宽资源分配性能,设计了一种基于时分多址(TDMA)机制的入网与网络维护方法,详细描述了用户竞争入网流程和网络维护机制。通过设计具体的帧结构,分析了用户入网概率。实验结果表明:提入网与网络维护方法能够支持多个移动用户的灵活接入和资源动态分配,5个终端全部接入所需的总时间仅为25 ms,该方法工程实现简单,能有效提升资源利用率。 展开更多
关键词 可见光通信 时分 竞争入网 网络维护 动态分配
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基于动态算法的民办高校教学管理优化策略
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作者 周飞 《贵阳学院学报(自然科学版)》 2024年第3期74-79,共6页
伴随信息化教育的到来,高校管理的难度日益增加,传统的管理方法在民办高校中往往伴随着专业性的不足。为解决高校管理上的问题,提出使用动态规划算法来对民办高校的教学管理进行优化。首先,对现有的动态规划算法进行阐述,提出针对原始... 伴随信息化教育的到来,高校管理的难度日益增加,传统的管理方法在民办高校中往往伴随着专业性的不足。为解决高校管理上的问题,提出使用动态规划算法来对民办高校的教学管理进行优化。首先,对现有的动态规划算法进行阐述,提出针对原始算法的两轮连续改进方案。其次,使用改进后的算法对高校的教学管理规划进行类型划分和事务合并实验分析。结果表明改进算法具备良好的稳定性,随着数据处理量的增加,算法的效率也呈比例增加,可有效用于高校管理优化。 展开更多
关键词 动态规划算法 类型划分 事务合并 高校教学管理优化
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基于EOF-DBSCAN-GRU的分布式光伏集群出力预测方法研究 被引量:1
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作者 麻吕斌 潘国兵 +3 位作者 蒋群 郭鹏 吴春华 赵宇航 《太阳能学报》 EI CAS CSCD 北大核心 2024年第1期39-46,共8页
提出一种基于EOF-DBSCAN划分集群的改进统计升尺度的光伏集群出力预测建模方法。针对传统统计升尺度方法子集群中光伏电站出力特性不一致问题,通过皮尔逊相关系数和经验正交函数(EOF)优化特征空间,再根据密度聚类模型(DBSCAN)对区域内... 提出一种基于EOF-DBSCAN划分集群的改进统计升尺度的光伏集群出力预测建模方法。针对传统统计升尺度方法子集群中光伏电站出力特性不一致问题,通过皮尔逊相关系数和经验正交函数(EOF)优化特征空间,再根据密度聚类模型(DBSCAN)对区域内光伏电站划分集群,从而增强光伏电站聚类后集群出力特性的一致性。针对待预测日权重系数时间序列动态特性的提取、预测问题,提出一种基于动态时间规整(DTW)的相似日选取算法。最后利用循环神经网络(GRU)模型进行光伏电站出力预测。实验表明该集群预测方法的平均误差百分数(MAPE)约为6.33%,均方根误差(RMSE)约为13.93 kW,均方误差(MSE)为194.25 kW,通过实际光伏电站数据证明了所提方法的准确性和有效性。 展开更多
关键词 分布式光伏电站 集群划分 经验正交函数 DBSCAN聚类算法 动态时间规整
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双转子转速协同规划的涡扇发动机加减速控制计划研究
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作者 强星煜 周登极 +1 位作者 尉询楷 王浩 《推进技术》 EI CAS CSCD 北大核心 2024年第4期233-242,共10页
当前涡扇发动机加减速控制计划,不能规划双轴加速进程,导致加速末期推力波动。本文提出了分阶段的加速度控制计划,按边界约束划分加速进程,基于动态稳定法设计初始加速度计划,通过寻找系统参数的超调临界点,协同修正初始加速度计划,满... 当前涡扇发动机加减速控制计划,不能规划双轴加速进程,导致加速末期推力波动。本文提出了分阶段的加速度控制计划,按边界约束划分加速进程,基于动态稳定法设计初始加速度计划,通过寻找系统参数的超调临界点,协同修正初始加速度计划,满足边界约束的同时保证双转子加速时间相同。在仿真验证环节,与基于定状态法的控制计划比较,本文方法可避免燃油振荡现象,推力超调量降低2.43%,推力稳定时间缩短1.045 s;与等转速增量的加速度控制计划比较,进一步改进了本文方法,推力响应时间缩短0.24 s,控制计划设计耗时为7.5781 s。综上,本文方法缩短了推力超调量和推力稳定时间,有望应用于发动机控制计划在线计算。 展开更多
关键词 涡扇发动机 分阶段控制计划 加速进程划分 动态稳定法 超调临界点
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细胞分裂周期蛋白73基因缺失抑制粟酒裂殖酵母细胞的有性生殖和有丝分裂
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作者 刘梦楠 白鑫 +3 位作者 余雯 李欣霖 丁祥 侯怡铃 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2024年第6期807-818,共12页
cdc73基因编码粟酒裂殖酵母(Schizosaccharomyces Pombe)RNA聚合酶Ⅱ辅助因子Cdc73,参与G_(2)期检查点激活并调控细胞周期。但cdc73基因缺失对细胞有丝分裂动力学的调控尚不清楚。本研究采用活细胞成像、荧光蛋白标记技术探究粟酒裂殖酵... cdc73基因编码粟酒裂殖酵母(Schizosaccharomyces Pombe)RNA聚合酶Ⅱ辅助因子Cdc73,参与G_(2)期检查点激活并调控细胞周期。但cdc73基因缺失对细胞有丝分裂动力学的调控尚不清楚。本研究采用活细胞成像、荧光蛋白标记技术探究粟酒裂殖酵母cdc73基因缺失后对细胞有性生殖和细胞有丝分裂中微管、肌动蛋白、线粒体和组蛋白动力学的影响。结果表明:在有性生殖中,cdc73基因缺失会导致子囊孢子长度增加14.23%,产4个孢子数量的细胞减少64.08%;活细胞成像结果分析发现,在有丝分裂中,分裂后期微管伸长的长度缩短11.21%,伸长时间减少17.39%;肌动蛋白环形成和收缩速率分别降低33.33%和26.09%,形成和收缩时间分别延长58.00%和40.38%;同时,肌动蛋白环、线粒体和组蛋白表达量都增加。本研究揭示了cdc73基因缺失可抑制有丝分裂中纺锤体的伸长,延缓肌动蛋白环的形成与收缩,为进一步探寻Cdc73蛋白在细胞分裂中参与调控微管和肌动蛋白动力学功能提供了一定的科学依据。 展开更多
关键词 cdc 73基因 粟酒裂殖酵母 有性生殖 有丝分裂 细胞动力学
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线粒体动力学调控肿瘤相关机制的研究进展
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作者 宁康浩 闫聚瀚 +2 位作者 闫晓冬 李佳程 李向东 《神经药理学报》 2024年第1期57-64,共8页
线粒体动力学是在生理或刺激状态下,线粒体持续不断的进行分裂和融合,从而调节线粒体在细胞内的分布、数量、大小以及形状的动态平衡过程。在细胞中,线粒体动力学调控与线粒体的功能密切相关,而线粒体的功能包括提供能量、调节钙离子稳... 线粒体动力学是在生理或刺激状态下,线粒体持续不断的进行分裂和融合,从而调节线粒体在细胞内的分布、数量、大小以及形状的动态平衡过程。在细胞中,线粒体动力学调控与线粒体的功能密切相关,而线粒体的功能包括提供能量、调节钙离子稳态,参与细胞程序性死亡、细胞信号转导、细胞代谢等。在肿瘤中,线粒体动力学调控与肿瘤细胞的增殖、迁移、治疗和耐药等密切相关,因此,线粒体动力学调控成为了肿瘤领域的研究热点,并在肿瘤治疗中显现出巨大潜力。该篇综述中,我们回顾了介导线粒体动力学调控的关键特征,并讨论了线粒体动力学调控肿瘤发生发展的相关机制和其在肿瘤治疗方面的可能。 展开更多
关键词 线粒体动力学 线粒体融合 线粒体分裂 肿瘤
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高铁列车动态定价与预售时段划分综合优化方法
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作者 许景 邓连波 +1 位作者 刘华儒 胡心磊 《交通运输系统工程与信息》 EI CSCD 北大核心 2024年第5期259-267,共9页
立足高铁收益亟需提高和灵活化市场票价体制实施的背景,本文考虑需求在预售期内各天的波动性和差异性,以及预售时段划分方案对铁路收益的影响,研究高铁列车动态定价与预售时段划分的综合优化问题。为预售期内每天构建独立的弹性需求函数... 立足高铁收益亟需提高和灵活化市场票价体制实施的背景,本文考虑需求在预售期内各天的波动性和差异性,以及预售时段划分方案对铁路收益的影响,研究高铁列车动态定价与预售时段划分的综合优化问题。为预售期内每天构建独立的弹性需求函数,考虑列车能力约束、需求约束及票价递增约束等条件,建立高铁列车动态定价与预售时段划分综合优化大规模非线性模型。根据模型特点,设计双层遗传—模拟退火算法求解,将优化问题分为外层预售时段划分、内层动态定价与票额分配的双层优化问题,内外两层分别采用遗传算法和模拟退火算法求解。最后,采用一个数值算例验证优化模型和求解算法的有效性,并探讨不同预售时段数量下的划分结果。结果表明,随预售时段数量的增加,预售期的划分主要集中在后半段;预售时段数量为5时,优化后,该数值算例的收益提高了约1.21%。 展开更多
关键词 铁路运输 动态定价 双层遗传—模拟退火算法 高铁列车 时段划分 席位分配
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