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Use of GIS Based Maps for Preliminary Assessment of Subsoil of Guwahati City 被引量:1
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作者 Binu Sharma Shaffi Kamal Rahman 《Journal of Geoscience and Environment Protection》 2016年第5期106-116,共11页
Guwahati, the major city in the North Eastern region of India is growing rapidly in every aspect with major infrastructures like sports complex, educational institutions, hospitals, flyovers, multiplex halls, etc. Kno... Guwahati, the major city in the North Eastern region of India is growing rapidly in every aspect with major infrastructures like sports complex, educational institutions, hospitals, flyovers, multiplex halls, etc. Knowledge of the subsurface soil condition is necessary to ensure the structural safety and serviceability of the above mentioned structures before any construction. Therefore, contour maps of Standard penetration test N value, ground water table and shear wave velocity map using Geographical Information System (GIS) platform will be of great help to the foundation designers at the initial stage for site selection and preliminary foundation design under static and seismic condition. Contour maps of Standard penetration test N value at different depth and average contour map of N value of Guwahati city have been prepared. Standard penetration Test N values and depth of water table were taken from a data base of 200 boreholes up to 30 meter depth to prepare N value contour map of Guwahati city. A regression equation between shear wave velocity V<sub>s</sub> and Standard penetration test N value based on twenty seven previous similar correlations was also developed. This regression equation was used to determine shear wave velocity of Guwahati city. The average shear wave velocities for 30 m depth for all locations had been determined and used to generate map on (GIS) platform. Other subsurface geotechnical information of Guwahati city like soil classification and depth to water level from ground surface is also presented in the form of GIS based maps in order to form a data base. 展开更多
关键词 Standard Penetration Test Shear Wave Velocity Contour map GIS based maps Subsurface Investigation
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Object-based image analysis for mapping geomorphic zones of coral reefs in the Xisha Islands, China 被引量:8
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作者 XU Jingping ZHAO Jianhua +5 位作者 LI Fang WANG Lin SONG Derui WEN Shiyong WANG Fei GAO Ning 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第12期19-27,共9页
Mapping regional spatial patterns of coral reef geomorphology provides the primary information to understand the constructive processes in the reef ecosystem. However, this work is challenged by the pixel-based image ... Mapping regional spatial patterns of coral reef geomorphology provides the primary information to understand the constructive processes in the reef ecosystem. However, this work is challenged by the pixel-based image classification method for its comparatively low accuracy. In this paper, an object-based image analysis(OBIA)method was presented to map intra-reef geomorphology of coral reefs in the Xisha Islands, China using Landsat 8satellite imagery. Following the work of the Millennium Coral Reef Mapping Project, a regional reef class hierarchy with ten geomorphic classes was first defined. Then, incorporating the hierarchical concept and integrating the spectral and additional spatial information such as context, shape and contextual relationships, a large-scale geomorphic map was produced by OBIA with accuracies generally more than 80%. Although the robustness of OBIA has been validated in the applications of coral reef mapping from individual reefs to reef system in this paper, further work is still required to improve its transferability. 展开更多
关键词 object-based Landsat 8 geomorphic mapping Xisha Islands
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基于改进RTAB-Map算法的爬壁机器人导航研究 被引量:2
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作者 覃超 唐东林 +3 位作者 游东潘 丁超 饶胜 何媛媛 《工程设计学报》 北大核心 2025年第1期32-41,共10页
针对爬壁机器人难以对大型石化装备壁面感知和自动化检测等难题,提出了一种改进RTAB-Map(real-time appearance-based mapping,基于外观的实时建图)算法,通过多传感器数据融合实现爬壁机器人定位、建图与导航。首先,搭建了具有壁面吸附... 针对爬壁机器人难以对大型石化装备壁面感知和自动化检测等难题,提出了一种改进RTAB-Map(real-time appearance-based mapping,基于外观的实时建图)算法,通过多传感器数据融合实现爬壁机器人定位、建图与导航。首先,搭建了具有壁面吸附能力的机器人运动底盘,以保证爬壁机器人在壁面灵活稳定运动;其次,针对爬壁机器人在壁面滑移导致的里程计累计误差问题,采用扩展卡尔曼滤波并融合编码器和惯性测量单元的数据,为建图和导航提供精确的里程计信息;再次,基于RTAB-Map算法对深度相机、激光雷达及里程计的数据进行融合,生成二维栅格和三维点云地图,实现对装备壁面的完整描述,并基于融合数据构建了爬壁机器人导航算法的框架;最后,在装备壁面进行了实验验证。结果表明:采用融合里程计算法,能显著减小航向角误差,航向角平均误差为0.78°,相对轮式里程计规划,航向角误差减少了88.94%;改进RTAB-Map算法提高了爬壁机器人在壁面环境下的建图与感知能力,结合路径规划算法,实现了机器人自主导航。研究结果对爬壁机器人自动化检测技术的研究及应用具有一定的参考意义。 展开更多
关键词 爬壁机器人 RTAB-map(基于外观的实时建图)算法 扩展卡尔曼滤波 多传感器融合 导航
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QTL Mapping for Fiber Quality Traits Based on a Dense Genetic Linkage Map with SSR,TRAP,SRAP and AFLP Markers in Cultivated Tetraploid Cotton 被引量:1
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作者 YU Ji-wen YU Shu-xun +1 位作者 ZHANG Jin-fa ZHAI Hong-hong 《棉花学报》 CSCD 北大核心 2008年第S1期34-34,共1页
Cotton is one of the most important economic crops in the world,and it p rovides natural fiber for the textile industry.With the advancement of the textile technology and increased consumption de-mands on cotton fiber... Cotton is one of the most important economic crops in the world,and it p rovides natural fiber for the textile industry.With the advancement of the textile technology and increased consumption de-mands on cotton fiber,both cotton yield and quality should be enhanced.However,cotton yield and fiber quality are complex quantitative traits andare usually ne gatively associated that hampers the sim-ultaneous improvement of lint yield and fiber quality by traditional breeding.In an attempt to over"come the limitations of the conventional bree ding,molecular breeding based on marker-assisted selec-tion is a reality as marker technology has become cheaper and higher thro ughput. 展开更多
关键词 QTLs AFLP QTL mapping for Fiber Quality Traits based on a Dense Genetic Linkage map with SSR TRAP SRAP and AFLP Markers in Cultivated Tetraploid Cotton SSR map
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Hot deformation of spray formed nickel-base superalloy using processing maps 被引量:8
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作者 康福伟 张国庆 +1 位作者 李周 孙剑飞 《中国有色金属学会会刊:英文版》 EI CSCD 2008年第3期531-535,共5页
The hot compression testing of hot isostatically pressed(HIPed) spray formed(SF) nickel-base superalloy was carried out by thermal mechanical simulator in the temperature range of 1 050-1 140 ℃ at strain rates of 0.0... The hot compression testing of hot isostatically pressed(HIPed) spray formed(SF) nickel-base superalloy was carried out by thermal mechanical simulator in the temperature range of 1 050-1 140 ℃ at strain rates of 0.01-10 s-1 and engineering strain of 50%. A processing map was developed on the basis of these data by using the principles of dynamic materials modeling. The microstructural evolution of deformed samples was also examined on the basis of optical and electron microscopic observations. The map exhibits two domains: the instability domain at the temperatures of 1 050 ℃ -1 110 ℃ and strain rate of 0.01 s-1, the stability domain at the temperatures of 1 110 ℃- 1 140 ℃ and strain rates of 1 s-1-10 s-1, with a peak efficiency of about 40%. The dynamic recrystallization(DRX) is observed in the stability domain and the deformed specimens are no cracking or instabilities. However, there is no DRX in the instability domain and the alloy exhibits flow instability with cracks due to poor workability. The optimum hot working condition was determined in the stability domain. 展开更多
关键词 喷溅成型 高温合金 加工处理 重结晶
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3DV quality model based depth maps for view synthesis in FTV system
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作者 张秋闻 安平 +2 位作者 张艳 张兆杨 王元庆 《Journal of Shanghai University(English Edition)》 CAS 2011年第4期335-341,共7页
Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems. When depth maps are derived using existing depth estimation methods, the depth distortions will cause undesirable artifacts ... Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems. When depth maps are derived using existing depth estimation methods, the depth distortions will cause undesirable artifacts in the synthesized views. To solve this problem, a 3D video quality model base depth maps (D-3DV) for virtual view synthesis and depth map coding in the FTV applications is proposed. First, the relationships between distortions in coded depth map and rendered view are derived. Then, a precisely 3DV quality model based depth characteristics is develop for the synthesized virtual views. Finally, based on D-3DV model, a multilateral filtering is applied as a pre-processed filter to reduce rendering artifacts. The experimental results evaluated by objective and subjective methods indicate that the proposed D-3DV model can reduce bit-rate of depth coding and achieve better rendering quality. 展开更多
关键词 free-viewpoint television (FTV) 3D video quality model base depth maps (D-3DV) view synthesis
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Ciphertext-Policy Attribute-Based Encryption for General Circuits from Bilinear Maps 被引量:2
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作者 HU Peng GAO Haiying 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2017年第2期171-177,共7页
In this paper, we present the first ciphertext-policy attribute-based encryption (CP-ABE) scheme for polynomial-size general circuits based on bilinear maps which is more suitable for practical use and more efficien... In this paper, we present the first ciphertext-policy attribute-based encryption (CP-ABE) scheme for polynomial-size general circuits based on bilinear maps which is more suitable for practical use and more efficient than multilinear maps. Our scheme uses a top-down secret sharing and FANOUT gate to resist the "backtracking attack" which is the main barrier expending access tree to general circuit. In the standard model, selective security of our scheme is proved. Comparing with current scheme for general circuits from bilinear maps, our work is more efficient. 展开更多
关键词 ciphertext-policy attribute-based encryption general circuits bilinear maps selective security
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Neuronal injury in the motor cortex after chronic stroke and lower limb motor impairment: a voxelbased lesion symptom mapping study 被引量:1
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作者 Alexandria M.Reynolds Denise M.Peters +5 位作者 Jennifer M.C.Vendemia Lenwood P.Smith Raymond C.Sweet Gordon C.Baylis Debra Krotish Stacy L.Fritz 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第7期766-772,共7页
Many studies have examined motor impairments using voxel-based lesion symptom mapping, but few are reported regarding the corresponding relationship between cerebral cortex injury and lower limb motor impairment analy... Many studies have examined motor impairments using voxel-based lesion symptom mapping, but few are reported regarding the corresponding relationship between cerebral cortex injury and lower limb motor impairment analyzed using this technique. This study correlated neuro- nal injury in the cerebral cortex of 16 patients with chronic stroke based on a voxel-based lesion symptom mapping analysis. Neuronal injury in the corona radiata, caudate nucleus and putamen of patients with chronic stroke could predict walking speed. The behavioral measure scores were consistent with motor deficits expected after damage to the cortical motor system due to stroke. These findings suggest that voxel-based lesion symptom mapping may provide a more accurate prognosis of motor recovery from chronic stroke according to neuronal injury in cerebral motor cortex. 展开更多
关键词 nerve regeneration magnetic resonance imaging STROKE cerebral cortex motor cortex voxel-based lesion symptom mapping motor function PROGNOSIS neural regeneration
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Variable-Coefficient Mapping Method Based on Elliptical Equation and Exact Solutions to Nonlinear SchrSdinger Equations with Variable Coefficient
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作者 GE Jian-Ya WANG Rui-Min +1 位作者 DAI Chao-Qing ZHANG Jie-Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4X期656-662,共7页
In this paper, by means of the variable-coefficient mapping method based on elliptical equation, we obtain explicit solutions of nonlinear Schrodinger equation with variable-coefficient. These solutions include Jacobi... In this paper, by means of the variable-coefficient mapping method based on elliptical equation, we obtain explicit solutions of nonlinear Schrodinger equation with variable-coefficient. These solutions include Jacobian elliptic function solutions, solitary wave solutions, soliton-like solutions, and trigonometric function solutions, among which some are found for the first time. Six figures are given to illustrate some features of these solutions. The method can be applied to other nonlinear evolution equations in mathematical physics. 展开更多
关键词 variable-coefficient mapping method based on elliptical equation nonlinear Schrodinger equation Jacobian elliptic function solutions solitonic solutions trigonometric function solutions
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Mineral Prospectivity Mapping Method Integrating Multi-Sources Geology Spatial Data Sets and Case-Based Reasoning 被引量:1
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作者 Binbin He Jianhua Chen +1 位作者 Cuihua Chen Yue Liu 《Journal of Geographic Information System》 2012年第2期77-85,共9页
Extracting and synthesizing information from existing and massive amounts of geology spatial data sets is of great scientific significance and has considerable value in its applications. To make mineral exploration le... Extracting and synthesizing information from existing and massive amounts of geology spatial data sets is of great scientific significance and has considerable value in its applications. To make mineral exploration less expensive, more efficient, and more accurate, it is important to move beyond traditional concepts and establish a rapid, efficient, and intelligent method of predicting the existence and location of minerals. This paper describes a case-based reasoning (CBR) method for mineral prospectivity mapping that takes spatial features of geology data into account and offers an intelligent approach. This method include a metallogenic case representation that combines spatial and attribute features, metallogenic case-based storage organization, and a metallogenic case similarity retrieval model. The experiments were performed in the eastern Kunlun Mountains, China using CBR and weights-of-evidence (WOE), respectively. The results show that the prediction accuracy of the CBR is higher than that of the WOE. 展开更多
关键词 MINERAL Prospectivity mapping Case-based Reasoning METALLOGENIC CASE Representation METALLOGENIC CASE Retrieval Eastern KUNLUN MOUNTAINS
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Research on Ubiquitous Map Information Organization Oriented to Location-Based Aggregation
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作者 Si Wang Guangxia Wang 《Journal of Geoscience and Environment Protection》 2022年第1期238-249,共12页
<div style="text-align:justify;"> In the era of information and communication technology (ICT) and big data, the map gradually shows a new qualitative feature of “spatiotemporal ubiquitous” due to th... <div style="text-align:justify;"> In the era of information and communication technology (ICT) and big data, the map gradually shows a new qualitative feature of “spatiotemporal ubiquitous” due to the extension of its object space and the geographic information it contains, which brings new challenges to map information organization. This paper analyzes the concept and information characteristics of the ubiquitous map. Based on that, it proposes a ubiquitous map information organization model oriented to location-based aggregation. This new model includes three parts as “ubiquitous map instance”, “location-based aggregation mode” and “map scene”. This paper focuses on the “map scene” part which is the core of the model and contains two mutually mapped aspects as “content scene” and “representation scene”. And both aspects are divided into three levels as “features” ←→ “elements” ←→ “scenes” according to ubiquitous map information characteristics and location-based aggregation mode. With cases of map decomposition, the application of the model is explained to illustrate its effectiveness. The model is expected to provide powerful data organization and management capabilities for ubiquitous map production and use. </div> 展开更多
关键词 Ubiquitous map Information Organization Location-based Aggregation map Scene
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An optical modulation format generation scheme based on spectral filtering and frequency-to-time mapping
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作者 张爱玲 张悦 +2 位作者 宋红云 姚远 潘洪刚 《Optoelectronics Letters》 EI 2018年第1期36-39,共4页
An optical modulation format generation scheme based on spectral filtering and frequency-to-time mapping is experimentally demonstrated. Many modulation formats with continuously adjustable duty radio and bit rate can... An optical modulation format generation scheme based on spectral filtering and frequency-to-time mapping is experimentally demonstrated. Many modulation formats with continuously adjustable duty radio and bit rate can be formed by changing the dispersion of dispersion element and the bandwidth of shaped spectrum in this scheme. In the experiment, non-return-to-zero(NRZ) signal with bit rate of 29.41 Gbit/s and 1/2 duty ratio return-to-zero(RZ) signal with bit rate of 13.51 Gbit/s are obtained. The maximum bit rate of modulation format signal is also analyzed. 展开更多
关键词 NRZ An optical modulation format generation scheme based on spectral filtering and frequency-to-time mapping
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MAP-based Audio Coding Compensation for Speaker Recognition
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作者 Tao Jiang Jiqing Han 《Journal of Signal and Information Processing》 2011年第3期165-169,共5页
The performance of the speaker recognition system declines when training and testing audio codecs are mismatched. In this paper, based on analyzing the effect of mismatched audio codecs in the linear prediction cepstr... The performance of the speaker recognition system declines when training and testing audio codecs are mismatched. In this paper, based on analyzing the effect of mismatched audio codecs in the linear prediction cepstrum coefficients, a method of MAP-based audio coding compensation for speaker recognition is proposed. The proposed method firstly sets a standard codec as a reference and trains the speaker models in this codec format, then learns the deviation distributions between the standard codec format and the other ones, next gets the current bias via using a small number adaptive data and the MAP-based adaptive technique, and then adjusts the model parameters by the type of coming audio codec format and its related bias. During the test, the features of the coming speaker are used to match with the adjusted model. The experimental result shows that the accuracy reached 82.4% with just one second adaptive data, which is higher 5.5% than that in the baseline system. 展开更多
关键词 AUDIO CODING COMPENSATION SPEAKER RECOGNITION map-based
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METHOD OF HIGH-LEVEL TECHNOLOGY MAPPING BASED ON KNOWLEDGE(RULE)
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作者 Ma Cong Wang Zuojian Liu Mingye (ASIC research Center of Beijing Institute of Technology, Beijing 100081) 《Journal of Electronics(China)》 2001年第1期24-31,共8页
This paper studies the linkage problem between the result of high-level synthesis and back-end technology, presents a method of high-level technology mapping based on knowl edge, and studies deeply all of its importan... This paper studies the linkage problem between the result of high-level synthesis and back-end technology, presents a method of high-level technology mapping based on knowl edge, and studies deeply all of its important links such as knowledge representation, knowledge utility and knowledge acquisition. It includes: (1) present a kind of expanded production about knowledge of circuit structure; (2) present a VHDL-based method to acquire knowledge of tech nology mapping; (3) provide solution control strategy and algorithm of knowledge utility; (4)present a half-automatic maintenance method, which can find redundance and contradiction of knowledge base; (5) present a practical method to embed the algorithm into knowledge system to decrease complexity of knowledge base. A system has been developed and linked with three kinds of technologies, so verified the work of this paper. 展开更多
关键词 HIGH-LEVEL synthesis TECHNOLOGY mapping VHDL HIGH-LEVEL TECHNOLOGY map PING KNOWLEDGE base KNOWLEDGE representation
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Correction of Inertial Navigation System’s Errors by the Help of Video-Based Navigator Based on Digital Terrarium Map
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作者 Oleg Yurjevich Kupervasser Alexander Alexandrovich Rubinstein 《Positioning》 2013年第1期89-108,共20页
This paper deals with the error analysis of a novel navigation algorithm that uses as input the sequence of images acquired from a moving camera and a Digital Terrain (or Elevation) Map (DTM/DEM). More specifically, i... This paper deals with the error analysis of a novel navigation algorithm that uses as input the sequence of images acquired from a moving camera and a Digital Terrain (or Elevation) Map (DTM/DEM). More specifically, it has been shown that the optical flow derived from two consecutive camera frames can be used in combination with a DTM to estimate the position, orientation and ego-motion parameters of the moving camera. As opposed to previous works, the proposed approach does not require an intermediate explicit reconstruction of the 3D world. In the present work the sensitivity of the algorithm outlined above is studied. The main sources for errors are identified to be the optical-flow evaluation and computation, the quality of the information about the terrain, the structure of the observed terrain and the trajectory of the camera. By assuming appropriate characterization of these error sources, a closed form expression for the uncertainty of the pose and motion of the camera is first developed and then the influence of these factors is confirmed using extensive numerical simulations. The main conclusion of this paper is to establish that the proposed navigation algorithm generates accurate estimates for reasonable scenarios and error sources, and thus can be effectively used as part of a navigation system of autonomous vehicles. 展开更多
关键词 Video-based NAVIGATOR Digital Terrarium map Autonomous Vehicles INERTIAL Navigation
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Mosaic Maps of China in Different Seasons Based on Data from HJ-1A/1B Satellites
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《Aerospace China》 2010年第1期F0003-F0003,共1页
关键词 mapS HJ Mosaic maps of China in Different Seasons based on Data from HJ-1A/1B Satellites
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基于气象相似日修正和IPO-DLinear的日前电力负荷预测
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作者 于惠钧 赵文川 +3 位作者 刘颉 徐银凤 邹海 辜海缤 《电力工程技术》 北大核心 2026年第2期121-130,共10页
现有电力负荷预测方法面临诸多挑战,尤其是在考虑气象因素对负荷波动的影响时,传统方法往往忽视气象特征与负荷之间复杂的非线性关系,导致预测精度不足。对此文中提出一种基于气象相似日修正(meteorological similar day correction,MS... 现有电力负荷预测方法面临诸多挑战,尤其是在考虑气象因素对负荷波动的影响时,传统方法往往忽视气象特征与负荷之间复杂的非线性关系,导致预测精度不足。对此文中提出一种基于气象相似日修正(meteorological similar day correction,MSDC)和改进鹦鹉优化(improved parrot optimizer,IPO)线性分解(decomposition-based linear,DLinear)的日前电力负荷预测模型。首先运用Logistic映射、自适应变异策略、螺旋波动搜索IPO对DLinear超参数进行优化,然后由DLinear提取数据的周期性和趋势性特征,最后通过比对气象特征欧氏距离修正负荷预测值,形成基于IPO-DLinear-MSDC的日前电力负荷预测模型。采用2024年6月至10月湖南株洲地区总电力负荷数据集进行仿真分析,IPO-DLinear-MSDC模型的输出平均绝对百分比误差(mean absolute percentage error,MAPE)、决定系数R2分别为4.67%、0.833,相较于IPO-DLinear与PO-DLinear模型,MAPE分别下降了0.83个百分点、1.43个百分点,R2分别提升了0.074、0.125。 展开更多
关键词 日前电力负荷预测 气象相似日修正(MSDC) 改进鹦鹉优化(IPO) 线性分解(DLinear) LOGISTIC映射 欧氏距离
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基于代价地图的非结构化道路参考线生成算法
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作者 孙介东 张旭东 +5 位作者 张硕 赵明安 户硕 张书杰 邹渊 何京 《汽车工程》 北大核心 2026年第1期37-49,60,共14页
针对非结构化道路起伏不定、凹凸不平、无明显边界标识等现象,本文融合坡度代价、粗糙度代价与边界代价,提出基于栅格代价地图的多层代价地图模型。设计搜索-优化-采样-优化的多阶段算法框架:采用改进A星算法生成栅格地图中的初始路径... 针对非结构化道路起伏不定、凹凸不平、无明显边界标识等现象,本文融合坡度代价、粗糙度代价与边界代价,提出基于栅格代价地图的多层代价地图模型。设计搜索-优化-采样-优化的多阶段算法框架:采用改进A星算法生成栅格地图中的初始路径并平滑,基于Frenet坐标系生成运动基元采样集,通过动态规划与二次规划双层优化机制,输出符合车辆运动学的平滑全局参考线。实车实验表明该方法在非结构化道路中能规划出平滑、满足运动学约束的全局路径,有较强的平顺性且满足车辆运动学约束。 展开更多
关键词 路径规划 栅格代价地图 A星算法 运动基元 二次规划
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金黄色稻米基因gpr1的图位克隆与功能分析
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作者 季永再 卞晓波 +6 位作者 冯志状 李范晶 胡卓尔 胡瑶洁 刘鹏程 马伯军 陈析丰 《生物工程学报》 北大核心 2026年第1期356-366,共11页
水稻颖壳与糙米颜色作为重要的农艺性状,长期以来在水稻育种及遗传学研究领域中被广泛应用。本研究从尼泊尔稻种资源中鉴定到一份稻穗及糙米均呈现金黄色的籼稻材料‘LAL SAR’,遗传分析表明上述表型受单隐性核基因控制,将其命名为gpr1(... 水稻颖壳与糙米颜色作为重要的农艺性状,长期以来在水稻育种及遗传学研究领域中被广泛应用。本研究从尼泊尔稻种资源中鉴定到一份稻穗及糙米均呈现金黄色的籼稻材料‘LAL SAR’,遗传分析表明上述表型受单隐性核基因控制,将其命名为gpr1(golden panicle and brown rice 1)。利用图位克隆技术将目标基因精细定位于水稻第3号染色体上47 kb的区间内,并确定其候选基因为LOC_Os03g60509。该基因编码查尔酮异构酶(chalcone isomerase, CHI),是黄酮类化合物生物合成途径中的关键酶。PCR扩增测序和RT-PCR表达分析发现,在‘LAL SAR’中gpr1基因的启动子区存在大片段插入,导致该基因表达缺失。利用CRISPR/Cas9技术在粳稻品种‘中花11’(‘ZH11’)中敲除了gpr1的显性等位基因GPR1,敲除植株的稻穗及糙米均呈现出金黄色,并且其颖壳中的柚皮素查尔酮的含量显著提高。研究结果表明GPR1基因参与水稻类黄酮的生物合成,本研究为提升水稻品质与遗传改良提供了重要的理论依据与基因资源,具有重要的应用价值。 展开更多
关键词 水稻 gpr1基因 图位克隆 查尔酮异构酶 类黄酮代谢
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职业教育虚拟仿真实训基地建设:问题分析、基本思路及实施路径
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作者 谭金石 高照忠 +2 位作者 朱腾 史合印 杨忞婧 《中国现代教育装备》 2026年第1期90-93,共4页
职业教育虚拟仿真实训基地建设顺应新时代职业教育发展趋势,满足复合型高素质技术技能型人才培养需求,实现职业教育“提质培优”,落实“三教”改革,深化产教融合。我国职业教育虚拟仿真实训基地建设起步晚,存在重设备轻资源、重建设轻... 职业教育虚拟仿真实训基地建设顺应新时代职业教育发展趋势,满足复合型高素质技术技能型人才培养需求,实现职业教育“提质培优”,落实“三教”改革,深化产教融合。我国职业教育虚拟仿真实训基地建设起步晚,存在重设备轻资源、重建设轻应用、信息技术与教学不融合、标准欠缺等问题。为此,本文以测绘地理信息技术专业群虚拟仿真实训基地建设为例,开展职业教育虚拟仿真实训基地建设路径研究与实践。首先深入分析当前专业课程实训教学中存在的问题,探索建设虚拟仿真实训基地的基本思路;然后从虚拟仿真实训环境、实训资源、师资队伍等方面开展实施路径研究。虚拟仿真实训基地的建设对职业教育质量提升和创新发展具有重要意义,并为促进职业教育虚拟仿真实训的推广与应用提供有益的借鉴。 展开更多
关键词 职业教育 虚拟仿真 实训基地 测绘地理信息技术 路径研究 实践探索
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