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探头高度变化对点位差的影响
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作者 赵连福 胡耀锋 刘永强 《地震地磁观测与研究》 1989年第6期51-54,共4页
本文通过探头在不同高度下对比测量,获取了大量的点位差数据。结果表明,约65%的测点探头高度变化对点位差没有明显影响。35%的测点影响较大。作者认为点位差的变化是流动地磁测量中的一种干扰因素,因此对变化原因进行了讨论,并提出选... 本文通过探头在不同高度下对比测量,获取了大量的点位差数据。结果表明,约65%的测点探头高度变化对点位差没有明显影响。35%的测点影响较大。作者认为点位差的变化是流动地磁测量中的一种干扰因素,因此对变化原因进行了讨论,并提出选建磁测点及野外磁测时应注意的几个问题。 展开更多
关键词 探头 高度 点位差 地震地磁学
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判断导线测角中出现较大误差点位的一种有效方法
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作者 王慎义 奚翔光 刘胜俊 《矿山测量》 1994年第1期14-16,36,共4页
本文介绍了一种判断导线测角较大误差点位的一种“正反三差曲线法”。其实质是:利用两组未经改正的观测值进行正反对算,得到两组同名点的坐标值,求出各同名点在坐标系中的距离,用ΔS表示,称之为“点位互差”。然后以ΔS作纵轴,... 本文介绍了一种判断导线测角较大误差点位的一种“正反三差曲线法”。其实质是:利用两组未经改正的观测值进行正反对算,得到两组同名点的坐标值,求出各同名点在坐标系中的距离,用ΔS表示,称之为“点位互差”。然后以ΔS作纵轴,以各导线点按正算方向,依次按照各边长排列作横轴,绘出其图像,在图像上分析可能出现较大误差的点位。 展开更多
关键词 测角精度 点位 导线测量
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坐标转换解算中基于验前中误差的稳健估计 被引量:3
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作者 周跃寅 潘国荣 孙海丽 《山东科技大学学报(自然科学版)》 CAS 2014年第3期69-76,共8页
通过公共点求解坐标转换参数时,如果公共坐标含有粗差,将会影响参数的求解,进而导致坐标转换结果产生较大的偏差。通过对比分析含粗差时的坐标中误差与验前中误差之间的比例关系,探究了坐标转换中利用离散的阈值函数与各点位较差的对比... 通过公共点求解坐标转换参数时,如果公共坐标含有粗差,将会影响参数的求解,进而导致坐标转换结果产生较大的偏差。通过对比分析含粗差时的坐标中误差与验前中误差之间的比例关系,探究了坐标转换中利用离散的阈值函数与各点位较差的对比关系,判断是否含粗差,以及观测数据含粗差时,各个点位坐标较差与最大点位坐标较差的关系,并且通过权变换避免了有效坐标的权误置零的情况,通过大量数据验证了算法的有效性。 展开更多
关键词 估计 坐标转换 验前中误 坐标中误 点位坐标较
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上海2000坐标系建立方法研究
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作者 陈浩 赵峰 +1 位作者 郭功举 耿晓燕 《工程勘察》 2023年第8期61-66,共6页
随着CGCS2000坐标系的推广应用,探索基于CGCS2000椭球的城市相对独立平面坐标系的需求越发迫切。本文根据上海市现有控制网资料,结合上海市地理位置和地形特征,综合考虑“长度变形有效覆盖最大化”与“点位差最小化”等原则,选取适合上... 随着CGCS2000坐标系的推广应用,探索基于CGCS2000椭球的城市相对独立平面坐标系的需求越发迫切。本文根据上海市现有控制网资料,结合上海市地理位置和地形特征,综合考虑“长度变形有效覆盖最大化”与“点位差最小化”等原则,选取适合上海市城市情况的上海2000坐标系的建设方案,该方案具有新老坐标成果点位差最小化的特色,减轻了坐标转换的工作量,节约了大量成本,为上海市新老坐标系统过渡提供有力保障,也为其他城市建立基于CGCS2000椭球的独立坐标系提供参考。 展开更多
关键词 CGCS2000 上海2000坐标系 长度变形 点位差
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GPS控制网优化设计思路及组网方案优选 被引量:2
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作者 曹正伟 乔亚奇 于诗深 《现代矿业》 CAS 2018年第7期241-242,共2页
详细分析了GPS网优化设计思路,结合实例,设计了5种GSP组网方案,通过进行点位平差分析,对不同方案的点位精度进行了对比分析,最终确定了最优组网方案,对于提高GSP组网设计效率以及GSP网精度具有一定的借鉴意义。
关键词 GPS控制网 优化设计 组网方案 点位
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Site discrepancy of synonymous codon usage in SARS coronavirus and other viruses in Coronaviridae
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作者 周童 顾万君 +2 位作者 马建民 孙啸 陆祖宏 《Journal of Southeast University(English Edition)》 EI CAS 2005年第2期203-206,共4页
The synonymous codon usage in the translational initiation and termination regions of genes of severe acute respiratory syndrome (SARS) coronavirus and five other viruses in Coronaviridae was systematically analyzed.T... The synonymous codon usage in the translational initiation and termination regions of genes of severe acute respiratory syndrome (SARS) coronavirus and five other viruses in Coronaviridae was systematically analyzed.The results indicate that most minor codons for these coronaviruses are preferentially used in the initial and terminal region.The minor codons preferentially used in the initial region are thought to have a negative effect on gene expression,which can be explained by the minor codon modulator hypothesis.It also indicates that the minor codons preferentially used in the terminal region may regulate the level of gene expression.The proposed results strongly imply that the minor codon modulator hypothesis can be applied to both some bacteria and some viruses. 展开更多
关键词 codon usage severe acute respiratory syndrome (SARS) CORONAVIRUS gene expression site discrepancy
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拓普康天狼星无人机在1:500地形图测绘中的应用 被引量:7
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作者 孟现彪 史雅茹 +1 位作者 王晓志 刘盛庆 《内蒙古电力技术》 2017年第5期90-92,共3页
拓普康天狼星无人机通过整台精密测时技术和RTK定位技术来确定每张航片拍摄的准确位置,这种精密定位技术实现了利用低空无人机制作1:500比例尺的地形图测绘。通过在某风电场220 kV升压站测图中的应用表明,该系统制作的平面精度和高程精... 拓普康天狼星无人机通过整台精密测时技术和RTK定位技术来确定每张航片拍摄的准确位置,这种精密定位技术实现了利用低空无人机制作1:500比例尺的地形图测绘。通过在某风电场220 kV升压站测图中的应用表明,该系统制作的平面精度和高程精度均符合相关规程的要求。与传统无人机航空摄影测量模式不同,无须布设像控点,极大提高了工作效率,节省了生产成本。 展开更多
关键词 无人机 地形图测绘 航测精度 像控点 点位 高程较
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对井下大压力巷道中线标定方法的探讨 被引量:1
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作者 杨树贵 艾春和 赵建立 《矿山测量》 1998年第4期37-39,共3页
本文对井下大压力巷道的中线标定方法进行了探讨,初步提出在此条件下的测量给线方法。
关键词 点位偏移 中线标定 压力巷道 巷道测量
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Position Group Contribution Method for Predicting the Normal Boiling Point of Organic Compounds 被引量:7
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作者 王强 马沛生 +1 位作者 王昶 夏淑倩 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第2期254-258,共5页
A new position group contribution model is proposed for the estimation of normal boiling data of organic compounds involving a carbon chain from C2 to C18.The characteristic of this method is the use of position distr... A new position group contribution model is proposed for the estimation of normal boiling data of organic compounds involving a carbon chain from C2 to C18.The characteristic of this method is the use of position distribution function.It could distinguish most of isomers that include cis-or trans-structure from organic compounds.Contributions for hydrocarbons and hydrocarbon derivatives containing oxygen,nitrogen,chlorine,bromine and sulfur,are given.Compared with the predictions,results made use of the most common existing group contribution methods,the overall average absolute difference of boiling point predictions of 417 organic compounds is 4.2 K;and the average absolute percent derivation is 1.0%,which is compared with 12.3 K and 3.2% with the method of Joback,12.1 K and 3.1% with the method of Constantinou-Gani.This new position contribution groups method is not only much more accurate but also has the advantages of simplicity and stability. 展开更多
关键词 normal boiling point PREDICTION position group contribution
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MPLPK:A mobile path localization protocol based on key nodes
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作者 王佳昊 Bao Honglai +2 位作者 Yang Xiaoming Wang Ruijin Qin Zhiguang 《High Technology Letters》 EI CAS 2015年第2期127-131,共5页
To alleviate the localization error introduced by irregular sensor network deployment, a new mo bile path localization based on key nodes (MPLPK) protocol is proposed. It can recognize all con cave/convex nodes in t... To alleviate the localization error introduced by irregular sensor network deployment, a new mo bile path localization based on key nodes (MPLPK) protocol is proposed. It can recognize all con cave/convex nodes in the network as fixed anchor nodes, and simplify the following localization process based on these key nodes. The MPLPK protocol is composed of three steps. After all key nodes are found in the network, a mobile node applying improved minimum spanning tree (MST) algorithm is introduced to traverse and locate them. By taking the concave/convex nodes as anchors, the complexity of the irregular network can be degraded. And the simulation results demonstrate that MPEPK has 20% to 40% accuracy improvements than connectivity-based and anchor-free three-di- mensional localization (CATL) and approximate convex decomposition based localization (ACDL). 展开更多
关键词 CONCAVE convex node mobile anchor node sensor network LOCALIZATION
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Precise orbit determination of Beidou Satellites with precise positioning 被引量:64
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作者 SHI Chuang ZHAO QiLe +6 位作者 LI Min TANG WeiMing HU ZhiGang LOU YiDong ZHANG HongPing NIU XiaoJi LIU JingNan 《Science China Earth Sciences》 SCIE EI CAS 2012年第7期1079-1086,共8页
Chinese Beidou satellite navigation system constellation currently consists of eight Beidou satellites and can provide preliminary service of navigation and positioning in the Asia-Pacific Region.Based on the self-dev... Chinese Beidou satellite navigation system constellation currently consists of eight Beidou satellites and can provide preliminary service of navigation and positioning in the Asia-Pacific Region.Based on the self-developed software Position And Navigation Data Analysis(PANDA) and Beidou Experimental Tracking Stations (BETS),which are built by Wuhan University,the study of Beidou precise orbit determination,static precise point positioning (PPP),and high precision relative positioning,and differential positioning are carried out comprehensively.Results show that the radial precision of the Beidou satellite orbit determination is better than 10 centimeters.The RMS of static PPP can reach several centimeters to even millimeters for baseline relative positioning.The precision of kinematic pseudo-range differential positioning and RTK mode positioning are 2-4 m and 5-10 cm respectively,which are close to the level of GPS precise positioning.Research in this paper verifies that,with support of ground reference station network,Beidou satellite navigation system can provide precise positioning from several decimeters to meters in the wide area and several centimeters in the regional area.These promising results would be helpful for the implementation and applications of Beidou satellite navigation system. 展开更多
关键词 compass/Beidou PANDA precise orbit determination (POD) Beidou difference
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Genome wide expression analysis of the effect of Socheongryong Tang in asthma model of mice 被引量:1
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作者 Chi-Yeon Lim Hyung-Woo Kim +1 位作者 Bu-Yeo Kim Su-In Cho 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2015年第2期168-174,共7页
OBJECTIVE:To investigate the molecular effect of Socheongryong Tang(SCRT,Xiaoqinglong Tang in Chinese) on whole genome level in asthma mouse model by microarray technology.METHODS:Asthma was induced by intranasal inst... OBJECTIVE:To investigate the molecular effect of Socheongryong Tang(SCRT,Xiaoqinglong Tang in Chinese) on whole genome level in asthma mouse model by microarray technology.METHODS:Asthma was induced by intranasal instillation of ovalbumin in mouse.After administration of SCRT on asthma-induced mouse,the expression of genes in lung tissue was measured using whole genome microarray.The functional implication of differentially expressed genes was performed using ontological analysis and the similarity of promoter structure of genes was also analyzed.RESULTS:Treatment of SCRT restored expression level of many up- or down-regulated genes in asthma model,and this recovery rate means SCRT could regulate a set of genes having specific TFBS binding sites.CONCLUSION:In this study,we identified a set of genes subjected to similar regulation by SCRT in asthma model in mice. 展开更多
关键词 Asthma Transcription factors Microarray analysis Genome wide expression Socheongryong Tang(Xiaoqinglong Tang)
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