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Molecular complexity of visual mapping:a challenge for regenerating therapy 预览
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作者 Mara Medori Gonzalo Spelzini Gabriel Scicolone 《中国神经再生研究:英文版》 SCIE CAS CSCD 2020年第3期382-389,共8页
Investigating the cellular and molecular mechanisms involved in the development of topographically ordered connections in the central nervous system constitutes an important issue in neurobiology because these connect... Investigating the cellular and molecular mechanisms involved in the development of topographically ordered connections in the central nervous system constitutes an important issue in neurobiology because these connections are the base of the central nervous system normal function.The dominant model to study the development of topographic maps is the projection from the retinal ganglion cells to the optic tectum/colliculus.The expression pattern of Eph/ephrin system in opposing gradients both in the retina and the tectum,labels the local addresses on the target and gives specific sensitivities to growth cones according to their topographic origin in the retina.The rigid precision of normal retinotopic mapping has prompted the chemoaffinity hypothesis,positing axonal targeting to be based on fixed biochemical affinities between fibers and targets.However,several lines of evidence have shown that the mapping can adjust to experimentally modified targets with flexibility,demonstrating the robustness of the guidance process.Here we discuss the complex ways the Ephs and ephrins interact allowing to understand how the retinotectal mapping is a precise but also a flexible process. 展开更多
关键词 AXON growth AXON guidance development EPH and EPHRIN mapping regeneration RETINAL GANGLION cells retino-tectal system
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Physical Forcing Induced Coastal Vulnerability along the Gulf of Guinea 预览
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作者 Angora Aman René A. Tano +3 位作者 Elisée Toualy Foungnigué Silué Kwasi Appeaning Addo Regina Folorunsho 《环境保护(英文)》 2019年第9期1194-1211,共18页
Coastal areas of the Gulf of Guinea experience accelerated degradation as a result of erosion and flooding associated with intensification of extreme marine-meteorological phenomena. The coastal erosion process, espec... Coastal areas of the Gulf of Guinea experience accelerated degradation as a result of erosion and flooding associated with intensification of extreme marine-meteorological phenomena. The coastal erosion process, especially on the sandy or muddy littoral, constitutes one of the main factors of the degradation of the Gulf of the Guinean coast. These risks, which are still poorly studied, could increase over the coming decades because of climate change and the human activities that exacerbate them. Data related to ocean forcing (tide, wave, and sea level anomaly), to hydrologic parameter (rainfall) and to the state (geomorphology, coastal slope, and rate of coastal retreat) of the coast were analyzed by several statistical methods and a numerical vulnerability model to map the vulnerability of the different coastlines of this region. The results showed that the vulnerability of these coastal areas is influenced by geomorphology, tide, waves and rainfall intensity. 24.34% and 37% of the entire coast are of low and moderate vulnerability respectively. While 26.98% and 11.66% are of high and very high vulnerability respectively. This information could facilitate developing sustainable policies to effectively manage hazards in this coastal zone. 展开更多
关键词 Mapping Physical FORCING COASTAL VULNERABILITY Index GULF of GUINEA
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A 2D GIS Approach for Mapping Aquiferous Zones Using Remotely Sensed Data within Obubra, Southeast-Nigeria 预览
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作者 Ebenezer A. Kudamnya Ruth O. Sylvanus +2 位作者 Mary T. Essien Adamu A. Vulegbo Benjamin O. Omang 《水资源与保护(英文)》 2019年第6期758-776,共19页
Groundwater is vital to the sustenance and well-being of man-kind, although it is constantly under immense pressure. For this reason, there is need to develop an effective, reliable, scientific and sustainable means o... Groundwater is vital to the sustenance and well-being of man-kind, although it is constantly under immense pressure. For this reason, there is need to develop an effective, reliable, scientific and sustainable means of delineating zones of groundwater occurrence and distribution with high precision in other to effectively explore for this resource. In this study, remote sensing (RS) and geographical information system (GIS) have been combined to develop thematic maps of the zones of groundwater occurrence and distribution based on variable factors such as;elevation, drainage, lineament, slope, lithology and soil. The analytical hierarchy procedure (AHP) was employed to classify and subsequently assign weight to each variable factor through weighted overlay analysis. Integration of these factors with their relative classes defined was used to produce a 2D-model for predicting surface aquifers mapped within Obubra. The study delineated three (3) surface aquifer zones representing groundwater potential zones. Zones representing high groundwater potential cover an area of approximately 331.94 Km2, accounting for 29.58% of the study area. The region that represents moderate to good groundwater occurrence and distribution covers an estimated area of approximately 648.42 Km2, occupying 57.78% of the study area. Zones with groundwater of low potential account for a total surface area of approximately 141.81 Km2 which is about 12.64% of the entire study area. Regions that show good to moderate and high groundwater potentials, have a wider distribution all across the study area except at the southernmost part. The study therefore shows that it is effective in delineating surface potential zones and hitherto a 2D surface aquifer model for groundwater exploration campaigns within Obubra and its environs. 展开更多
关键词 GROUNDWATER AQUIFER Mapping AHP REMOTE Sensing ZONES
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以《黄帝内经》为例论中医取象比类的结构特征 被引量:1
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作者 石勇 《中华中医药杂志》 CAS CSCD 北大核心 2019年第2期542-545,共4页
取象比类是中医象思维的主要方法。文章针对取象比类的结构特征提出'鲜花原理',认为取象比类以具有主体心理可及的'共性之象'为基础,以'类比可及性'为前提,运用类比映射,在自然、人体、疾病诸象间寻求类比,实... 取象比类是中医象思维的主要方法。文章针对取象比类的结构特征提出'鲜花原理',认为取象比类以具有主体心理可及的'共性之象'为基础,以'类比可及性'为前提,运用类比映射,在自然、人体、疾病诸象间寻求类比,实现知识迁移。由'鲜花原理'推导出归类型映射结构,后者拓展了对取象比类的界定,对接了阴阳五行思维,将自然和人体作阴阳五行归属,通过映射的方式认知人体结构和生理病理,这是中医取象比类在结构上的最大特征。 展开更多
关键词 取象比类 类比 映射 黄帝内经 结构特征 鲜花原理 归类型映射
Current status and potential application of navigated transcranial magnetic stimulation in neurosurgery: a literature review
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作者 Xiaojing Fang Meige Liu +2 位作者 Changyu Lu Yuanli Zhao Xianzeng Liu 《中华神经外科杂志(英文)》 CSCD 2019年第2期108-114,共7页
Transcranial magnetic stimulation (TMS) is a noninvasive neurophysiologic technique that can stimulate the human brain.Positioning of the coil was often performed based merely on external landmarks on the head,meaning... Transcranial magnetic stimulation (TMS) is a noninvasive neurophysiologic technique that can stimulate the human brain.Positioning of the coil was often performed based merely on external landmarks on the head,meaning that the anatomical target in the cortex remains inaccurate.Navigated transcranial magnetic stimulation (nTMS) combines a frameless stereotactic navigational system and TMS coil and can provide a highly accurate delivery of TMS pulses with the guidance of imaging.Therefore,many novel utilities for TMS could be explored due to the ability of precise localization.Many studies have been published,which indicate nTMS enables presurgical functional mapping.This review aimed to provide a comprehensive literature review on nTMS,especially the principles and clinical applications of nTMS.All articles in PubMed with keywords of 'motor mapping,' 'presurgical mapping,' 'navigated transcranial magnetic stimulation,' and 'language mapping' published from 2000 to 2018 were included in the study.Frequently cited publications before 2000 were also included.The most valuable published original and review articles related to our objective were selected.Motor mapping of nTMS is validated to be a trustful tool to recognize functional areas belonging to both normal and lesioned primary motor cortex.It can offer reliable mapping of speech and motor regions at cortex prior to operation and has comparable accuracy as direct electrical cortical stimulation.nTMS is a powerful tool for mapping of motor and linguistic function prior to operation,has high application value in neurosurgery and the treatment of neurological and psychiatric diseases,and has gained increasing acceptance in neurosurgical centers across the world. 展开更多
关键词 TRANSCRANIAL magnetic STIMULATION Motor MAPPING SPEECH MAPPING NEUROSURGERY
基于Mapping方法的京沪高速铁路区域景观规划分析 预览
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作者 邓敬 邱建 殷荭 《中国园林》 北大核心 2019年第5期96-101,共6页
高速铁路的快速发展在改变人们出行方式、缩短“时空距离”、提高工作效率的同时,也在急剧改变着城市景观风貌和区域景观格局,这为风景园林规划设计提出了新的研究课题,需要拓宽研究视野、拓展研究方法。景观都市主义的Mapping方法,一... 高速铁路的快速发展在改变人们出行方式、缩短“时空距离”、提高工作效率的同时,也在急剧改变着城市景观风貌和区域景观格局,这为风景园林规划设计提出了新的研究课题,需要拓宽研究视野、拓展研究方法。景观都市主义的Mapping方法,一直在研究如何让景观更有效地介入空间、生态和社会的发展进程,用多种方式对空间或地理坐标基础上的信息进行可视化操作。通过Mapping的“层-组-群”方法,以穿越与连接了多地域、多层次区域景观的京沪高速铁路为研究对象,研究京沪高铁沿线的相关层级信息、叠组的关联与群化关系,展示出网络化与可视性的景观因素与特征。研究结果旨在为跨区域高速铁路的景观规划提供参考。 展开更多
关键词 风景园林 景观都市主义 区域景观规划 Mapping方法 “层-组-群” 京沪高铁
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Optimal Positioning of Mobile Platforms for Accurate Manipulation Operations 预览
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作者 Iker Lluvia Ander Ansuategi +5 位作者 Carlos Tubí o Loreto Susperregi aki Maurtua Elena Lazkano 《电脑和通信(英文)》 2019年第5期1-16,共16页
Many mobile robotics applications, especially in industrial environments, require the robot to perform safe navigation and then reach the goal with a high precision. In this research work, the objective is to analyze ... Many mobile robotics applications, especially in industrial environments, require the robot to perform safe navigation and then reach the goal with a high precision. In this research work, the objective is to analyze the appropriateness of autonomous natural navigation strategies for mobile manipulation tasks. The system must position itself in a realistic map, follow a path closely and then achieve an accurate positioning in the destination point in order to be able to perform the manipulation, inspection or pick task efficiently. Autonomous navigation is not able to fulfill the accuracy required by some of the jobs so that a second positioning system using vision is proposed in this paper. The experiments show that localization systems have, on average, an error greater than a decimetre and how an additional positioning system can reduce it to a few millimetres. 展开更多
关键词 Mobile ROBOT Mapping LOCALIZATION VISION ACCURATE POSITIONING
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基于外形数控程序的PCB Mapping可视化分析 预览
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作者 周进群 刘义亚 冯勇 《汽车实用技术》 2019年第7期169-171,180共4页
大数据分析是目前非常实用的一种分析手段,通过收集数据并对其进行清洗,能够获得大量的有效数据,对这些数据进行关联后通过分类、聚类、寻优等手段可获得人工无法发现的隐藏在数据中的一些问题及特性,从而为产品质量、生产效率等方面改... 大数据分析是目前非常实用的一种分析手段,通过收集数据并对其进行清洗,能够获得大量的有效数据,对这些数据进行关联后通过分类、聚类、寻优等手段可获得人工无法发现的隐藏在数据中的一些问题及特性,从而为产品质量、生产效率等方面改善提供思路和方向,这也是各行各业都在不断推崇的一种分析途径。现阶段,PCB工厂数据追述困难,现有的数据收集系统只能记录追溯到批次,无法实现PNL及拼版追溯管理,且数据需经历多次记录汇总,才能录入系统中,工作效率十分低下,且存在数据丢失的风险,导致无法进行智能化管理。针对以上分析,现需根据外形数控的走刀程序结合二维码坐标程序进行mapping追溯管理系统开发,实现信息在线收集,利用成品拼版二维码实现拼版信息追溯,为后期大数据清洗、分析、关联、分类、聚类等操作提供基础,提高工厂的生产效率,为企业带来良好的效益。 展开更多
关键词 大数据分析 PCB MAPPING 聚类
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高等数学中映射概念的实例教学法 预览 被引量:1
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作者 滕吉红 鲁志波 黄晓英 《河南教育学院学报:自然科学版》 2019年第1期63-66,共4页
从映射的角度阐述函数概念的发展历程,给出了密码学、通信领域以及哲学层面上的一些映射概念的实例,其目的是尽量挖掘数学基础知识与学生所学专业的联系,使数学联系生活、数学联系科技、数学联系哲学,进而激发学生的求知欲,发挥其主动... 从映射的角度阐述函数概念的发展历程,给出了密码学、通信领域以及哲学层面上的一些映射概念的实例,其目的是尽量挖掘数学基础知识与学生所学专业的联系,使数学联系生活、数学联系科技、数学联系哲学,进而激发学生的求知欲,发挥其主动学习的潜能. 展开更多
关键词 映射 函数 狄利克雷函数 移位密码 信源编码 一一映射
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磁共振Mapping技术诊断兔进展期椎间盘退变 预览
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作者 胡莹莹 应金威 +1 位作者 赵琪雯 王庆军 《中国康复理论与实践》 CSCD 北大核心 2019年第2期172-177,共6页
目的探索磁共振T2mapping和T1mapping成像诊断兔进展期腰椎间盘退变的应用价值。方法 7只新西兰兔行椎间盘退变造模。造模前以及造模后1个月、3个月,行矢状位T1WI、T2WI、T2mapping和T1mapping扫描,基于T2WI,对L1~S1的6个椎间盘行Pfirrm... 目的探索磁共振T2mapping和T1mapping成像诊断兔进展期腰椎间盘退变的应用价值。方法 7只新西兰兔行椎间盘退变造模。造模前以及造模后1个月、3个月,行矢状位T1WI、T2WI、T2mapping和T1mapping扫描,基于T2WI,对L1~S1的6个椎间盘行Pfirrmann分级,基于T2mapping和T1mapping测量椎间盘T2值和T1值。观察相应椎间盘病理改变,以病理结果非进展期和进展期退变为标准,使用接受者操作特征(ROC)曲线判断各成像指标的诊断效能。结果造模前、造模后1个月和造模后3个月,椎间盘T2值显著降低(F=24.224, P <0.001),椎间盘T1值无显著性差异(F=2.191, P=0.116)。诊断进展期椎间盘退变的效能从高到低依次为:T2mapping+T1mapping=T2mapping> T1mapping> Pfirrmann评分。结论 T2mapping可以较准确地区分非进展期和进展期椎间盘退变。 展开更多
关键词 椎间盘退变 磁共振成像 MAPPING
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Lipschitz continuity for solutions of the ?-Poisson equation
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作者 Xingdi Chen 《中国科学:数学英文版》 SCIE CSCD 2019年第10期1935-1946,共12页
In this paper, we study the Lipschitz continuity for solutions of the ?-Poisson equation. After characterizing the boundary conditions for the Lipschitz continuity of ?-harmonic mappings, we present four equivalent co... In this paper, we study the Lipschitz continuity for solutions of the ?-Poisson equation. After characterizing the boundary conditions for the Lipschitz continuity of ?-harmonic mappings, we present four equivalent conditions for the(K, K′)-quasiconformal solutions of the ?-Poisson equation with a nonhomogeneous term to be Lipschitz continuous. 展开更多
关键词 weighted LAPLACIAN operator LIPSCHITZ CONTINUITY DIRICHLET boundary problem HARMONIC MAPPING (K K′)-quasiconformal MAPPING
Antlion optimizer algorithm based on chaos search and its application 预览
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作者 ZHANG Zhenxing YANG Rennong +3 位作者 LI Huanyu FANG Yuhuan HUANG Zhenyu ZHANG Ying 《系统工程与电子技术:英文版》 SCIE EI CSCD 2019年第2期352-365,共14页
Aiming at the problems of premature convergence and easily falling into local optimums of the antlion optimization algorithm, a chaos antlion optimization algorithm based on the chaos search is proposed. Firstly, in t... Aiming at the problems of premature convergence and easily falling into local optimums of the antlion optimization algorithm, a chaos antlion optimization algorithm based on the chaos search is proposed. Firstly, in the algorithm, the population is initialized by using the tent chaotic mapping, and the self-adaptive dynamic adjustment of chaotic search scopes is proposed in order to improve the overall fitness and the optimization efficiency of the population. Then, the tournament strategy is used to select antlions. Finally, the logistic chaos operator is used to optimize the random walk of ants, which forms a global and local parallel search mode with the antlion’s foraging behavior. The performance algorithm is tested through 13 complex high-dimensional benchmark functions and three dimensional path planning problems. The experimental results of six complex high-dimensional benchmark functions show that the presented algorithm has a better convergence speed and precision than the standard antlion algorithm and other optimization algorithms, and is suitable for the optimization of complex high dimensional functions. The trajectory planning experimental results show that compared with the antlion optimizer(ALO) algorithm, grey wolf optimizer(GWO), particle swarm optimization(PSO) and artificial bee colony(ABC) algorithm, it has advantages in speed and accuracy to obtain a specific path, and it is of great value in actual problems. 展开更多
关键词 antlion OPTIMIZER (ALO) ALGORITHM chaos theory TENT MAPPING TOURNAMENT selection strategy logistic MAPPING path planning
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脊柱胸腰段骨折椎体的三维形态学分析 预览
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作者 苏启航 张锦飙 +4 位作者 李聪 张岩 潘杰 李立钧 谭军 《骨科》 CAS 2019年第5期379-383,共5页
目的通过三维骨折线分布图的大数据形态学分析,揭示脊柱胸腰段椎体(T11~L2)骨折的好发模式及骨折特点,从而指导临床决策。方法回顾性分析2017年1月至2019年3月AO分型为A型的压缩性胸腰段椎体(T11~L2)骨折病人的临床资料。共纳入了257例... 目的通过三维骨折线分布图的大数据形态学分析,揭示脊柱胸腰段椎体(T11~L2)骨折的好发模式及骨折特点,从而指导临床决策。方法回顾性分析2017年1月至2019年3月AO分型为A型的压缩性胸腰段椎体(T11~L2)骨折病人的临床资料。共纳入了257例研究对象,平均年龄为46岁,266个骨折椎体,其中T11骨折15例,T12骨折69例,L1骨折95例,L2骨折87例。把病人高分辨率CT数据导入到Mimics软件中,通过阈值分割,重建出骨折椎体模型。依次将各个骨折椎体的骨折线临摹到相应正常椎体模型上,获得各个椎体节段的3D骨折线分布图。结果 3D骨折线分布图揭示骨折线主要集中在椎体的上半部分以及椎体的外1/3部分,并且沿着椎体的前方和侧方呈环状楔形分布。结论首次将骨折的Mapping技术应用到胸腰段骨折的分析研究中,骨折线分布图揭示了胸腰段骨折的好发模式及形态学特点,从流行病学及形态学方面提高了对胸腰段骨折的认识,有助于提升后续的科学研究及改善临床决策。 展开更多
关键词 脊柱骨折 三维断层扫描成像 Mapping技术
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Monitoring Zenithal Total Delays over the three different climatic zones from IGS GPS final products:A comparison between the use of the VMF1 and GMF mapping functions
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作者 Benachour Labib Jianguo Yan +2 位作者 Jean-Pierre Barriot Fangzhao Zhang Peng Feng 《大地测量与地球动力学:英文版》 2019年第2期93-99,共7页
The International GNSS Service(IGS) final products(ephemeris and clocks-correction) have made the GNSS an indispensable low-cost tool for scientific research, for example sub-daily atmospheric water vapor monitoring. ... The International GNSS Service(IGS) final products(ephemeris and clocks-correction) have made the GNSS an indispensable low-cost tool for scientific research, for example sub-daily atmospheric water vapor monitoring. In this study, we investigate if there is a systematic difference coming from the choice between the Vienna Mapping Function 1(VMF1) and the Global Mapping Function(GMF) for the modeling of Zenith Total Delay(ZTD) estimates, as well as the Integrated Precipitable Water Vapor(IPWV) estimates that are deduced from them. As ZTD estimates cannot be fully separated from coordinate estimates, we also investigated the coordinate repeatability between subsequent measurements.For this purpose, we monitored twelve GNSS stations on a global scale, for each of the three climatic zones(polar, mid-latitudes and tropical), with four stations on each zone. We used an automated processing based on the Bernese GNSS Software Version 5.2 by applying the Precise Point Positioning(PPP)approach, L3 Ionosphere-free linear combination, 7 cutoff elevation angle and 2 h sampling. We noticed an excellent agreement with the ZTD estimates and coordinate repeatability for all the stations w.r.t to CODE(the Center for Orbit Determination in Europe) and USNO(US Naval Observatory) products, except for the Antarctic station(Davis) which shows systematic biases for the GMF related results. As a final step, we investigated the effect of using two mapping functions(VMF1 and GMF) to estimate the IPWV,w.r.t the IPWV estimates provided by the Integrated Global Radiosonde Archive(IGRA). The GPS-derived IPWV estimates are very close to the radiosonde-derived IPWV estimates, except for one station in the tropics(Tahiti). 展开更多
关键词 International GNSS Service (IGS) VIENNA MAPPING FUNCTION 1 (VMF1) Global MAPPING FUNCTION (GMF) Precise Point Positioning (PPP) Zenith TOTAL DELAY (ZTD) Zenith Wet DELAY (ZWD) Integrated Precipitable Water Vapor (IPWV)
大数据环境下基于元模型控制的数据质量保障技术研究 预览
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作者 杨冬菊 徐晨阳 《计算机工程与科学》 CSCD 北大核心 2019年第2期197-206,共10页
数据集成环节,越来越丰富的异构源数据给集成后数据质量的提升带来了新的挑战和困难。针对传统ETL模型在数据集成后出现的数据冗余、无效、重复、缺失、不一致、错误值及格式出错等数据质量问题,提出了基于元数据模型控制的ETL集成模型... 数据集成环节,越来越丰富的异构源数据给集成后数据质量的提升带来了新的挑战和困难。针对传统ETL模型在数据集成后出现的数据冗余、无效、重复、缺失、不一致、错误值及格式出错等数据质量问题,提出了基于元数据模型控制的ETL集成模型,并对数据集成过程中的各种映射规则进行了详细的定义,通过将抽取、转换、加载环节的元模型和映射机制相结合,能够有效地保证集成后数据的数据质量。提出的元模型已经应用到科技资源管理数据集成业务中。通过科技资源管理数据集成实例分析,验证了此数据集成方案能够有效地支撑大数据环境下数据仓库的构建和集成后数据质量的提升。 展开更多
关键词 大数据 数据仓库 ETL 元数据模型 映射 数据集成
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Genetic dissection of hexanol content in soybean seed through genome-wide association analysis 预览
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作者 XIA Ning YAN Wen-bing +7 位作者 WANG Xiao-qi SHAO Yu-peng YANG Ming-ming WANG Zhi-kun ZHAN Yu-hang TENG Wei-li HAN Ying-peng SHI Yan-guo 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第6期1222-1229,共8页
Hexanol is a major compound contributing to the off-flavors(the bean-like odor)of soybean derived soymilk.The most effective way to reduce the off-flavors of soymilk is the screening and utilization of soybean cultiva... Hexanol is a major compound contributing to the off-flavors(the bean-like odor)of soybean derived soymilk.The most effective way to reduce the off-flavors of soymilk is the screening and utilization of soybean cultivars with improved hexanol content.However,no genome-wide genetic analysis for this particular trait has been conducted to date.The objective of the present study was to dissect the genetic basis of hexanol content in soybean seed through genome-wide association analysis(GWAS).A total of 105 soybean accessions were analyzed for hexanol content in a three-year experiments and genotyped by sequencing using the specific locus amplified fragment sequencing(SLAF-seq)approach.A total of 25 724 single nucleotide polymorphisms(SNPs)were obtained with minor allele frequencies(MAF)>5%.GWAS showed that 25 quantitative trait nucleotides(QTNs)were significantly associated with the hexanol concentration in soybean seed.These identified QTNs distributed on different genomic regions of the 15 chromosomes.A total of 91 genes were predicted as candidate genes underlying the seed hexanol level and six candidates were predicted possibly underlying the seed hexanol by gene based association.In this study,GWAS has been proven to be an effective way to dissect the genetic basis of the hexanol concentration in multiple genetic backgrounds.The identified beneficial alleles and candidate genes might be valuable for the improvement of marker-assisted breeding efficiency for low hexanol level and help to explore possible molecular mechanisms underlying hexanol content in soybean seed. 展开更多
关键词 GENOME-WIDE association mapping SOYBEAN HEXANOL CONCENTRATION CANDIDATE GENES
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水利工程规划阶段工程测绘重点探究 预览
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作者 郭熙和 孟秋雨 杜洪全 《工程建设(重庆)》 2019年第9期39-40,共2页
就一个完整的水利工程的施工和设计工作的实施来看,牵涉到大量的工序。工程测绘工作对于水利工程来说是十分重要的,在水里工程的建造中,各个阶段都是会利用到诸多的测绘方式以及测绘技术。在实施测绘操作工序的时候,需要对各项重点工作... 就一个完整的水利工程的施工和设计工作的实施来看,牵涉到大量的工序。工程测绘工作对于水利工程来说是十分重要的,在水里工程的建造中,各个阶段都是会利用到诸多的测绘方式以及测绘技术。在实施测绘操作工序的时候,需要对各项重点工作加以侧重关注。需要认真的遵照各项工作的实际要求,遵从各项操作原则,才能够切实的高效的开展水利工程规划设计工作。这篇文章主要围绕水利工程规划过程中工程测绘工作的关键实施综合研究,希望能够对这项工作的健康发展有所帮助。 展开更多
关键词 水利工程 规划阶段 测绘
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无人机低空遥感技术在大比例尺地形图测绘中的应用 预览
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作者 冯红红 《世界有色金属》 2019年第10期209-210,共2页
本文对无人机遥感系统的构成与数据处理进行了阐述,以新疆塔城建邺区为例,研究了大比例尺地形图测绘中无人机低空遥感测绘技术运用的实践。
关键词 无人机 遥感 测绘
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Biholomorphic Mappings and the Extension Operators on New Hartogs Domains
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作者 Yan Yan CUI Chao Jun WANG Hao LIU 《数学学报:英文版》 SCIE CSCD 2019年第5期671-689,共19页
In this paper, we generalize the Roper-Suffridge operator on the extended Hartogs domains. By using the geometric properties and the growth theorems of subclasses of biholomorphic mappings, we obtain the generalized o... In this paper, we generalize the Roper-Suffridge operator on the extended Hartogs domains. By using the geometric properties and the growth theorems of subclasses of biholomorphic mappings, we obtain the generalized operators preserve the properties of parabolic and spirallike mappings of type β and order ρ, SΩ*(β, A, B), almost starlike mapping of complex order λ on ΩN under different conditions, and thus we get the corresponding results on the unit ball Bn in Cn. The conclusions lead to some known results. 展开更多
关键词 Biholomorphic MAPPING Roper-Suffridge OPERATOR Hartogs DOMAIN
基于方位信息的改进LZW前缀编码方案 预览
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作者 韩宾 张红红 +1 位作者 江虹 丁一 《计算机科学》 CSCD 北大核心 2019年第8期157-162,共6页
LZW压缩算法在实时采集与无线传输中具有重要应用价值,一般采用采集-压缩-传输的工作模式,该模式下的较高压缩比可极大降低对无线传输的压力。但在采集速度较快、数据传输带宽较低、硬件资源受限的情况下,在对采样点概率分布较均匀的数... LZW压缩算法在实时采集与无线传输中具有重要应用价值,一般采用采集-压缩-传输的工作模式,该模式下的较高压缩比可极大降低对无线传输的压力。但在采集速度较快、数据传输带宽较低、硬件资源受限的情况下,在对采样点概率分布较均匀的数字信号进行压缩时,易出现压缩率不高或采集速度与压缩速度不匹配的问题。对此,文中提出了基于方位信息的改进LZW前缀编码方案。该改进压缩算法基于压缩比因子对采样点进行映射操作,使其能够标识后面相邻采样点的压缩情况,然后通过采样点间的方位信息,缩短采样点的码长,实现对采样点数据的压缩。实验表明,与原LZW压缩算法相比,该改进算法在不增加算法复杂度和硬件存储空间的条件下,压缩比可提高26.25%,证明了该算法在采集系统中的有效性。 展开更多
关键词 LZW算法 方位信息 数字信号 映射 编码
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