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基于电路地图的带拖车移动机器人路径搜索 被引量:3
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作者 田静 黄亚楼 刘作军 《机器人》 EI CSCD 北大核心 2005年第6期521-525,共5页
采用电路映射地图进行环境建模,在等效尺寸的基础上对带拖车移动机器人的路径规划进行研究.这种方法在局部规划的同时,兼备了路径规划的全局性,有效地从根本上避免了人工势场法等局部分析方法容易陷入局部最优的不足.理论分析和仿真验... 采用电路映射地图进行环境建模,在等效尺寸的基础上对带拖车移动机器人的路径规划进行研究.这种方法在局部规划的同时,兼备了路径规划的全局性,有效地从根本上避免了人工势场法等局部分析方法容易陷入局部最优的不足.理论分析和仿真验证了本方法的可行性和正确性. 展开更多
关键词 电路映射地图 路径规划 环境建模 拖车移动机器人
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基于改进GNG网络的机器人路径规划方法 被引量:1
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作者 任伟建 刘东辉 +2 位作者 王显伟 王天任 康朝海 《系统仿真学报》 CAS CSCD 北大核心 2014年第5期1000-1005,1014,共7页
针对在机器人路径规划中,增长神经气(GNG)算法生成地图映射速度较慢,并且存在个别错误路径,随后的路径搜索中,一次A*算法也不能搜索到最短路径的问题,提出了一种改进的GNG结合两次A*算法的机器人路径规划方法。在地图映射生成阶段,先给... 针对在机器人路径规划中,增长神经气(GNG)算法生成地图映射速度较慢,并且存在个别错误路径,随后的路径搜索中,一次A*算法也不能搜索到最短路径的问题,提出了一种改进的GNG结合两次A*算法的机器人路径规划方法。在地图映射生成阶段,先给GNG一个预设规模的网络再进行神经元生长,这样比原算法减少了在神经元生长时的计算量;在路径搜索阶段,利用两次A*算法首先实现路径粗搜索,然后实现细搜索,并证明了二次搜索的路径更短。对于地图映射中出现的错误路径,也进行了处理。仿真结果表明,改进的地图映射算法与其它地图映射算法相比计算时间少,地图的映射精度高,最终可以找到一条机器人可行走的最短路径。 展开更多
关键词 增长神经气 A*算法 地图映射 最短路径
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基于改进遗传算法的出租车共乘线路规划研究 被引量:7
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作者 张玺君 张祺瑞 +1 位作者 张丽娟 王晨辉 《交通运输系统工程与信息》 EI CSCD 北大核心 2019年第6期123-128,共6页
常规出租车运行模式效率低,增加了城市的拥堵.针对兰州市出租车搭载率低和行驶路线规划不合理等问题,设计一种以最高搭载率、最短行驶距离为目标的函数,考虑出租车的容量限制、车辆行驶距离限制及上下车人数约束等问题的共乘模式.建立... 常规出租车运行模式效率低,增加了城市的拥堵.针对兰州市出租车搭载率低和行驶路线规划不合理等问题,设计一种以最高搭载率、最短行驶距离为目标的函数,考虑出租车的容量限制、车辆行驶距离限制及上下车人数约束等问题的共乘模式.建立基于改进遗传算法的出租车共乘线路规划模型.通过采用锦标赛选择策略、站点片段交叉设计和站点监督式变异等操作对模型进行求解.最后用兰州市出租车历史轨迹数据进行实验分析,结果表明,运用设计的出租车线路规划模型及改进的遗传算法,能够快速地得到优化路径,实现多辆出租车的规划路径满足最高搭载率及最短距离的要求. 展开更多
关键词 智能交通 站点编码 共乘线路 线路优化 地图映射
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BREW手机赛车游戏若干技术难点及实现 被引量:1
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作者 郑勇 刘乃琦 《成都信息工程学院学报》 2006年第1期48-51,共4页
描述了在手机上表现滞钝的传统实现思路,并在此基础上,使用了不同于传统思路的新方法实现赛道弯曲和地图映射,并给出程序伪代码,最后提供了一些提高效率的优化措施。
关键词 赛车游戏 赛道弯曲 地图映射 效率优化
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Application of RgMap system on digital regional geological survey 被引量:2
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作者 Qingying ZHAO Jinxin HE +1 位作者 Guoliang WANG Xiumei HAN 《Global Geology》 2007年第1期95-99,共5页
Digital geological mapping fundamentally broke through the traditional working pattern,successfully carried out the geological mapping digitalization.By using the RGMAP system to field digital geological mapping,the a... Digital geological mapping fundamentally broke through the traditional working pattern,successfully carried out the geological mapping digitalization.By using the RGMAP system to field digital geological mapping,the authors summarized the method of work and the work flow of the RGMAPGIS during the field geological survey.First,we prepared material,set up the PRB gallery,then put the geographic base map under the background maplayer and organizing the field hand map,forming the field factual datum map.At last,the geological space database is formed. 展开更多
关键词 digital mapping PRB gallery factual datum map spatial database
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基于电商评论情感分析的用户聚类方法研究 被引量:1
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作者 王盈 张文龙 唐卓然 《现代信息科技》 2023年第16期24-27,33,共5页
针对电子商务中的商品评论信息过载问题,运用情感关联分析理论,通过挖掘商品评论信息中的商品特征及相应的情感反馈,建立商品特征细粒度上的情感分值向量,在此基础上利用SOM神经网络模型对评价用户进行聚类,建立电商用户情感画像,并针... 针对电子商务中的商品评论信息过载问题,运用情感关联分析理论,通过挖掘商品评论信息中的商品特征及相应的情感反馈,建立商品特征细粒度上的情感分值向量,在此基础上利用SOM神经网络模型对评价用户进行聚类,建立电商用户情感画像,并针对不同电商用户群体特征制定个性化营销策略,从而帮助平台商家从繁杂的商品评论中快速获取有效信息。实验中在线评论取自图书类商品,数据均来源于Amason。实验结果表明,该方法具有良好的应用效果。 展开更多
关键词 电子商务 在线评论 情感分析 自组织映射地图 用户聚类
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Lossless Digital Watermarking Scheme for Image Maps 被引量:2
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作者 SUN Jianguo ZHENG Chonghui GAO Di 《China Communications》 SCIE CSCD 2014年第8期125-130,共6页
A lossless digital watermarking scheme,which was zero- perturbation on the content and graphics for the digital image maps,is proposed.During the simulation,the scheme has been utilized to model the copyright protecti... A lossless digital watermarking scheme,which was zero- perturbation on the content and graphics for the digital image maps,is proposed.During the simulation,the scheme has been utilized to model the copyright protection program as a commerce application.Compared to the traditional digital watermarking schemes,our scheme operates in redundancy areas of maps and is scalable to topology changes.Experimental results show that,with respect to the geometric attacks and image transformed,the performance of our scheme is better than the classical algorithms based space or frequency domain with much lower complexity.. 展开更多
关键词 information hiding digitalwatermarking copyright protection digitalmaps
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Mapping Deciduous Broad-leaved Forested Swamps Using ALOS/Palsar Data
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作者 BIAN Hongfeng YAN Tingting +2 位作者 ZHANG Zhengxiang HE Chunguang SHENG Lianxi 《Chinese Geographical Science》 SCIE CSCD 2016年第3期352-365,共14页
Accurate, updated information on the distribution of wetlands is essential for estimating net fluxes of greenhouse gases and for effectively protecting and managing wetlands. Because of their complex community structu... Accurate, updated information on the distribution of wetlands is essential for estimating net fluxes of greenhouse gases and for effectively protecting and managing wetlands. Because of their complex community structure and rich surface vegetation, deciduous broad-leaved forested swamps are considered to be one of the most difficult types of wetland to classify. In this research, with the support of remote sensing and geographic information system, multi-temporal radar images L-Palsar were used initially to extract the forest hydrological layer and phenology phase change layer as two variables through image analysis. Second, based on the environmental characteristics of forested swamps, three decision tree classifiers derived from the two variables were constructed to explore effective methods to identify deciduous broad-leaved forested swamps. Third, this study focused on analyzing the classification process between flat-forests, which are the most severely disturbed elements, and forested swamps. Finally, the application of the decision tree model will be discussed. The results showed that: 1) L-HH band(a L band with wavelength of 0–235 m in HH polarization mode; HH means Synthetic Aperture Radars transmit pulses in horizontal polarization and receive in horizontal polarization) in the leaf-off season is shown to be capable of detecting hydrologic conditions beneath the forest; 2) the accuracy of the classification(forested swamp and forest plat) was 81.5% based on hydrologic features, and 83.5% was achieved by combining hydrologic features and phenology response features, which indicated that hydrological characteristics under the forest played a key role. The HHOJ(refers to the band created by the subtraction with HH band in October and HH band in July) achieved by multi-temporal radar images did improve the classification accuracy, but not significantly, and more leaf-off radar images may be more efficient than multi-seasonal radar images for inland forested swamp mapping; 3) the lower separability between forested swamps dominated by vegetated surfaces and forest plat covered with litter was the main cause of the uncertainty in classification, which led to misleading interpretations of the pixel-based classification. Finally, through the analysis with kappa coefficients, it was shown that the value of the intersection point was an ideal choice for the variable. 展开更多
关键词 forested swamp Palsar radar images forest hydrological characteristics multi-temporal technique decision tree classifier
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Self-Organizing Maps in Seismic Image Segmentation
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作者 Carlos Ramirez Miguel Argaez +1 位作者 Pablo Guiilen Gladys Gonzalez 《Computer Technology and Application》 2012年第9期624-629,共6页
Unsupervised neural networks such as the Kohonen Self-Organizing Maps (SOM) have been widely used for searching natural clusters in multidimensional and massive data. One example where the data available for analysi... Unsupervised neural networks such as the Kohonen Self-Organizing Maps (SOM) have been widely used for searching natural clusters in multidimensional and massive data. One example where the data available for analysis can be extremely large is seismic interpretation for hydrocarbon exploration. In order to assist the interpreter in identifying characteristics of interest confined in the seismic data, the authors present a set of data attributes that can be used to train a SOM in such a way that zones of interest can be automatically identified or segmented, reducing time in the interpretation process. The authors show how to associate SOM to 2D color maps to visually identify the clustering structure of the input seismic data, and apply the proposed technique to a 2D synthetic seismic dataset of salt structures. 展开更多
关键词 Self-organizing maps image segmentation seismic attributes.
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Pseudo-Anosov Mapping Classes and Their Representations by Products of Two Dehn Twists 被引量:1
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作者 Chaohui ZHANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2009年第3期281-292,共12页
Let S be a Riemann surface of analytically finite type (p, n) with 3p-3+n 〉 0. Let a ∈ S and S = S - {a}. In this article, the author studies those pseudo-Anosov maps on S that are isotopic to the identity on S a... Let S be a Riemann surface of analytically finite type (p, n) with 3p-3+n 〉 0. Let a ∈ S and S = S - {a}. In this article, the author studies those pseudo-Anosov maps on S that are isotopic to the identity on S and can be represented by products of Dehn twists. It is also proved that for any pseudo-Anosov map f of S isotopic to the identity on S, there are infinitely many pseudo-Anosov maps F on S - {b} = S - {a, b}, where b is a point on S, such that F is isotopic to f on S as b is filled in. 展开更多
关键词 Riemann surface Pseudo-Anosov map Dehn twist Teichmullerspace Bers fiber space
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Self-maps of p-local infinite projective spaces 被引量:1
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作者 LIN XianZu 1,2 1 College of Mathematics and Computer Science,Fujian Normal University,Fuzhou 350108,China 2 Institute of Mathematics,Academy of Mathematics and Systems Science,Beijing 100190,China 《Science China Mathematics》 SCIE 2012年第4期739-744,共6页
Abstract Denote by z(p) (resp. Zp) the p localization (resp. p completion) of z. Then we have the canonical inclusion Z(p)→ zp. Let S2n-1(p) be the p-local (2n- 1)-sphere and let B2n(p) be a connected p... Abstract Denote by z(p) (resp. Zp) the p localization (resp. p completion) of z. Then we have the canonical inclusion Z(p)→ zp. Let S2n-1(p) be the p-local (2n- 1)-sphere and let B2n(p) be a connected p-local space satisfying S2n-l(p)≌ΩB2n(p), then H*B2n(p),Z(p)) = Z(p)[U] with |u| = 2n. Define the degree of a self-map f of B2n(p) to be k E Z(p) such that f*(u) = ku. Using the theory of integer-valued polynomials we show that there exists a self-map of B2n(p) of degree k if and only if k is an n-th power in Zp. 展开更多
关键词 infinite projective space self-map integer-valued polynomial
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High precision landing site mapping and rover localization for Chang'e-3 mission 被引量:21
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作者 LIU ZhaoQin DI KaiChang +7 位作者 PENG Man WAN WenHui LIU Bin LI LiChun YU TianYi WANG BaoFeng ZHOU JianLiang CHEN HongMin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2015年第1期139-149,共11页
This paper presents the comprehensive results of landing site topographic mapping and rover localization in Chang’e-3 mission.High-precision topographic products of the landing site with extremely high resolutions(up... This paper presents the comprehensive results of landing site topographic mapping and rover localization in Chang’e-3 mission.High-precision topographic products of the landing site with extremely high resolutions(up to 0.05 m)were generated from descent images and registered to CE-2 DOM.Local DEM and DOM with 0.02 m resolution were produced routinely at each waypoint along the rover traverse.The lander location was determined to be(19.51256°W,44.11884°N,-2615.451 m)using a method of DOM matching.In order to reduce error accumulation caused by wheel slippage and IMU drift in dead reckoning,cross-site visual localization and DOM matching localization methods were developed to localize the rover at waypoints;the overall traveled distance from the lander is 114.8 m from cross-site visual localization and 111.2 m from DOM matching localization.The latter is of highest accuracy and has been verified using a LRO NAC image where the rover trajeactory is directly identifiable.During CE-3 mission operations,landing site mapping and rover localization products including DEMs and DOMs,traverse maps,vertical traverse profiles were generated timely to support teleoperation tasks such as obstacle avoidance and rover path planning. 展开更多
关键词 Chang'e-3 Yutu rover landing site mapping rover localization descent camera navigation camera
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Embedding Periodic Maps on Surfaces into Those on S^3 被引量:1
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作者 Yu GUO Chao WANG +1 位作者 Shicheng WANG Yimu ZHANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2015年第2期161-180,共20页
Call a periodic map h on the closed orientable surface Σg extendable if h extends to a periodic map over the pair(S3, Σg) for possible embeddings e : Σg→ S3. The authors determine the extendabilities for all perio... Call a periodic map h on the closed orientable surface Σg extendable if h extends to a periodic map over the pair(S3, Σg) for possible embeddings e : Σg→ S3. The authors determine the extendabilities for all periodical maps on Σ2. The results involve various orientation preserving/reversing behalves of the periodical maps on the pair(S3, Σg). To do this the authors first list all periodic maps on Σ2, and indeed the authors exhibit each of them as a composition of primary and explicit symmetries, like rotations, reflections and antipodal maps, which itself should be interesting. A by-product is that for each even g,the maximum order periodic map on Σg is extendable, which contrasts sharply with the situation in the orientation preserving category. 展开更多
关键词 Symmetry of surface Symmetry of 3-sphere Extendable action
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On brain activity mapping: Insights and lessons from Brain Decoding Project to map memory patterns in the hippocampus 被引量:1
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作者 TSIEN Joe Z. LI Meng +9 位作者 OSAN Remus CHEN GuiFen LIN LongNian WANG Phillip Lei FREY Sabine FREY Julietta ZHU DaJiang LIU TianMing ZHAO Fang KUANG Hui 《Science China(Life Sciences)》 SCIE CAS 2013年第9期767-779,共13页
The BRAIN project recently announced by the president Obama is the reflection of unrelenting human quest for cracking the brain code, the patterns of neuronal activity that define who we are and what we are. While the... The BRAIN project recently announced by the president Obama is the reflection of unrelenting human quest for cracking the brain code, the patterns of neuronal activity that define who we are and what we are. While the Brain Activity Mapping proposal has rightly emphasized on the need to develop new technologies for measuring every spike from every neuron, it might be helpful to consider both the theoretical and experimental aspects that would accelerate our search for the organizing principles of the brain code. Here we share several insights and lessons from the similar proposal, namely, Brain Decoding Project that we initiated since 2007. We provide a specific example in our initial mapping of real-time memory traces from one part of the memory circuit, namely, the CA1 region of the mouse hippocampus. We show how innovative behavioral tasks and appropriate mathematical analyses of large datasets can play equally, if not more, important roles in uncovering the specific-to-general feature-coding cell assembly mechanism by which episodic memory, semantic knowledge, and imagination are generated and organized. Our own experiences suggest that the bottleneck of the Brain Project is not only at merely developing additional new technologies, but also the lack of efficient avenues to disseminate cutting edge platforms and decoding expertise to neuroscience community. Therefore, we propose that in order to harness unique insights and extensive knowledge from various investigators working in diverse neuroscience subfields, ranging from perception and emotion to memory and social behaviors, the BRAIN project should create a set of International and National Brain Decoding Centers at which cutting-edge recording technologies and expertise on analyzing large datasets analyses can be made readily available to the entire community of neuroscientists who can apply and schedule to perform cutting-edge research. 展开更多
关键词 BRAIN project Brain Decoding Project brain activity map learning and memory episodic memory semantic knowledge IMAGINATION concepts fear conditioning earthquake experiences neural code
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On the Regularity Theories for Harmonic Maps from Finsler Manifolds
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作者 Wei ZHU 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2012年第4期595-600,共6页
The author studies the regularity of energy minimizing maps from Finsler manifolds to Riemannian manifolds. It is also shown that the energy minimizing maps are smooth, when the target manifolds have no focal points.
关键词 Finsler manifolds Harmonic map REGULARITY
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Holomorphic Maps from Sasakian Manifolds into Khler Manifolds
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作者 Bin SHEN Yibing SHEN Xi ZHANG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2013年第4期575-586,共12页
The authors consider ±(Φ, J)-holomorphic maps from Sasakian manifolds into Koihler manifolds, which can be seen as counterparts of holomorphic maps in Kiihler ge- ometry. It is proved that those maps must be h... The authors consider ±(Φ, J)-holomorphic maps from Sasakian manifolds into Koihler manifolds, which can be seen as counterparts of holomorphic maps in Kiihler ge- ometry. It is proved that those maps must be harmonic and basic. Then a Schwarz lemma for those maps is obtained. On the other hand, an invariant in its basic homotopic class is obtained. Moreover, the invariant is just held in the class of basic maps. 展开更多
关键词 Sasakian manifold HARMONIC Schwarz lemma Homotopic invariant
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