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THE THEORETICAL STUDIES OF PRODUCT ALIGNMENT OF THE REACTIONS OF Na,F WITH CH_3I 被引量:3
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作者 Ke Li HAN Guo Zhong HE Nan Quan LOU State Key Laboratory of Molecular Reaction Dynamics,Dalian Institute of Chemical Physics,CAS,Dalian 116012,China 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第6期517-520,共4页
The NaI and IF product rotational alignment of the reactions of Na,F+CH_3I has been theoretically studied in a LEPS PES.The product alignment versus the relative translational energy of the reactants has been obtained.
关键词 NA THE THEORETICAL STUDIES Of PRODUCT alignment Of THE REACTIONS Of Na f WITH CH3I CH
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Correction to“Alignment of Human Aquaporin 4 and β-Amyloid Proteins May Indicate Involvement of β-Amyloid in Brain Water Homeostasis and Prevention of Brain Edema”
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《Chronic Diseases and Translational Medicine》 2025年第3期239-239,共1页
S.Lehrer and P.H.Rheinstein,“Alignment of Human Aquaporin 4 and fß-Amyloid Proteins May Indicate Involvement of fß-Amyloid in Brain Water Homeostasis and Prevention of Brain Edema,”Chronic Diseases and Tra... S.Lehrer and P.H.Rheinstein,“Alignment of Human Aquaporin 4 and fß-Amyloid Proteins May Indicate Involvement of fß-Amyloid in Brain Water Homeostasis and Prevention of Brain Edema,”Chronic Diseases and Translational Medicine 9(2023):177-181.https://doi.org/10.1002/cdt3.64. 展开更多
关键词 PREVENTION brain edema brain water homeostasis human aquaporin f amyloid proteins alignment
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Algorithm and experiments of six-dimensional force/torque dynamic measurements based on a Stewart platform 被引量:15
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作者 Wen Ke Du Fuzhou Zhang Xianzhi 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2016年第6期1840-1851,共12页
Stewart platform(SP) is a promising choice for large component alignment, and interactive force measurements are a novel and significant approach for high-precision assemblies. The designed position and orientation(P&... Stewart platform(SP) is a promising choice for large component alignment, and interactive force measurements are a novel and significant approach for high-precision assemblies. The designed position and orientation(P&O) adjusting platform, based on an SP for force/torquedriven(F/T-driven) alignment, can dynamically measure interactive forces. This paper presents an analytical algorithm of measuring six-dimensional F/T based on the screw theory for accurate determination of external forces during alignment. Dynamic gravity deviations were taken into consideration and a compensation model was developed. The P&O number was optimized as well.Given the specific appearance of repeated six-dimensional F/T measurements, an approximate cone shape was used for spatial precision analysis. The magnitudes and directions of measured F/Ts can be evaluated by a set of standards, in terms of accuracy and repeatability. Experiments were also performed using a known applied load, and the proposed analytical algorithm was able to accurately predict the F/T. A comparison between precision analysis experiments with or without assembly fixtures was performed. Experimental results show that the measurement accuracy varies under different P&O sets and higher loads lead to poorer accuracy of dynamic gravity compensation. In addition, the preferable operation range has been discussed for high-precision assemblies with smaller deviations. 展开更多
关键词 Dynamic gravity compensation f/t-driven alignment Precision analysis P&O adjusting platform Six-dimensional f/T
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舰载捷联惯导动基座F-QUEST初始对准方法 被引量:4
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作者 李杨 高敬东 +1 位作者 胡柏青 李开龙 《海军工程大学学报》 CAS 北大核心 2014年第6期32-36,共5页
针对目前基于惯性系的捷联惯导动基座对准方法信息利用率不高及矢量观测选取不确定性导致对准精度下降的问题,提出了一种新的舰载捷联惯导动基座滤波四元数估计(filter quaternion estimation,FQUEST)对准方法。构建了捷联惯导动基座初... 针对目前基于惯性系的捷联惯导动基座对准方法信息利用率不高及矢量观测选取不确定性导致对准精度下降的问题,提出了一种新的舰载捷联惯导动基座滤波四元数估计(filter quaternion estimation,FQUEST)对准方法。构建了捷联惯导动基座初始对准模型,并利用姿态矩阵链式法则将惯导初始对准转化为姿态确定问题,进而采用F-QUEST算法求取姿态矩阵以实现捷联惯导动基座对准。车载试验结果表明:相比传统方法,新方法具有更高的对准精度和更快的收敛速度,水平姿态角误差只需3s即可收敛到0.01°。 展开更多
关键词 捷联惯导 动基座 初始对准 姿态确定 f-QUEST
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基于降维CKF和平滑的SINS/OD动基座对准 被引量:3
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作者 黄湘远 汤霞清 武萌 《系统工程与电子技术》 EI CSCD 北大核心 2016年第9期2135-2141,共7页
为了提高捷联惯导(strapdown inertial navigation system,SINS)/里程计(odometer,OD)动基座对准精度,使对准过程中具备一定精度的位置导航能力,提出了一种动基座非线性对准方法。首先对非线性系统进行简化并应用降维容积卡尔曼滤波(red... 为了提高捷联惯导(strapdown inertial navigation system,SINS)/里程计(odometer,OD)动基座对准精度,使对准过程中具备一定精度的位置导航能力,提出了一种动基座非线性对准方法。首先对非线性系统进行简化并应用降维容积卡尔曼滤波(reduced dimension cubature Kalman filter,RD-CKF)进行非线性对准,保证非线性对准过程中能够进行位置导航,对准结束时保证失准角为小角度。然后非线性R-T-S平滑至初始时刻进行校正,利用卡尔曼滤波再次对准,获得对准结束时刻高精度的姿态和位置导航。进行了实车实验,实验结果表明了方案的有效性。 展开更多
关键词 容积卡尔曼滤波 降维 初始对准 R-T-S平滑
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BSAlign:A Library for Nucleotide Sequence Alignment 被引量:2
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作者 Haojing Shao Jue Ruan 《Genomics, Proteomics & Bioinformatics》 SCIE CAS CSCD 2024年第2期135-142,共8页
Increasing the accuracy of the nucleotide sequence alignment is an essential issue in genomics research.Although classic dynamic programming(DP)algorithms(e.g.,Smith–Waterman and Needleman–Wunsch)guarantee to produc... Increasing the accuracy of the nucleotide sequence alignment is an essential issue in genomics research.Although classic dynamic programming(DP)algorithms(e.g.,Smith–Waterman and Needleman–Wunsch)guarantee to produce the optimal result,their time complexity hinders the application of large-scale sequence alignment.Many optimization efforts that aim to accelerate the alignment process generally come from three perspectives:redesigning data structures[e.g.,diagonal or striped Single Instruction Multiple Data(SIMD)implementations],increasing the number of parallelisms in SIMD operations(e.g.,difference recurrence relation),or reducing search space(e.g.,banded DP).However,no methods combine all these three aspects to build an ultra-fast algorithm.In this study,we developed a Banded Striped Aligner(BSAlign)library that delivers accurate alignment results at an ultra-fast speed by knitting a series of novel methods together to take advantage of all of the aforementioned three perspectives with highlights such as active F-loop in striped vectorization and striped move in banded DP.We applied our new acceleration design on both regular and edit distance pairwise alignment.BSAlign achieved 2-fold speed-up than other SIMD-based implementations for regular pairwise alignment,and 1.5-fold to 4-fold speed-up in edit distance-based implementations for long reads.BSAlign is implemented in C programing language and is available at https://github.com/ruanjue/bsalign. 展开更多
关键词 Pairwise alignment Edit distance Striped vectorization Banded dynamic programming f evaluation
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光纤端面偏移对光纤F-P可调谐滤波器性能影响
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作者 陈超 薛景锋 +1 位作者 孙义斌 江琴 《光学技术》 CAS CSCD 北大核心 2016年第3期239-241,共3页
在光纤F-P可调谐滤波器进行滤波调谐的过程中经常会出现光纤端面偏移的问题,从而导致其滤波性能下降。通过ZEMAX光学仿真软件对其光纤F-P腔部分进行仿真,模拟两光纤端面发生径向偏移和产生倾角时的情况,通过对仿真结果分析得出当发生径... 在光纤F-P可调谐滤波器进行滤波调谐的过程中经常会出现光纤端面偏移的问题,从而导致其滤波性能下降。通过ZEMAX光学仿真软件对其光纤F-P腔部分进行仿真,模拟两光纤端面发生径向偏移和产生倾角时的情况,通过对仿真结果分析得出当发生径向偏移时将会导致光纤F-P可调谐滤波器的峰值透过率减小,插入损耗增加;在产生倾角时将会导致光纤F-P可调谐滤波器的3dB带宽增加以及阻带抑制能力减弱,而当倾角大于0.005°时其滤波性能将会发生明显衰减。 展开更多
关键词 光纤f-P可调谐滤波器 光纤对准 ZEMAX 仿真研究
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多用户MIMO系统中一种自由度分配算法 被引量:1
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作者 高慧 周欣瑞 +1 位作者 吴仁铭 朱谦 《计算机工程》 CAS CSCD 北大核心 2015年第1期71-74,81,共5页
近年来迭代干扰对齐技术得到了较多的关注,通过迭代干扰对齐算法可设计线性预编码矩阵,以最大化多输入多输出系统的总速率。但目前将自由度(Do F)分配方式作为系统总速率影响因素的研究较少。为此,提出一种Do F分配算法,通过改进模拟退... 近年来迭代干扰对齐技术得到了较多的关注,通过迭代干扰对齐算法可设计线性预编码矩阵,以最大化多输入多输出系统的总速率。但目前将自由度(Do F)分配方式作为系统总速率影响因素的研究较少。为此,提出一种Do F分配算法,通过改进模拟退火算法从而得到可使系统总速率达到最大的Do F分配方式。Do F分配问题是组合优化问题,采用模拟退火算法可较好地解决该问题。仿真结果表明,该算法所获得的系统总速率接近遍历算法的性能,具有更低的复杂度。尤其当系统变得复杂(用户数目增加,或者天线数目增加)时,改进模拟退火算法的低复杂度优势更为明显。 展开更多
关键词 多输入多输出 迭代干扰对齐 自由度分配 模拟退火算法 总速率
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2014-2019年海南富克站甚高频相干散射雷达回波数据集 被引量:2
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作者 金晗 燕春晓 +1 位作者 陈罡 阎敬业 《中国科学数据(中英文网络版)》 CSCD 2021年第2期73-82,共10页
子午工程海南富克站甚高频(very high frequency,VHF)相干散射雷达位于我国海南省儋州市富克镇(109.1°E,19.5°N),隶属于中国科学院国家空间科学中心。雷达波束正交于电离层E和F层磁力线,其回波主要来自沿磁力线排列的电离层... 子午工程海南富克站甚高频(very high frequency,VHF)相干散射雷达位于我国海南省儋州市富克镇(109.1°E,19.5°N),隶属于中国科学院国家空间科学中心。雷达波束正交于电离层E和F层磁力线,其回波主要来自沿磁力线排列的电离层场向不规则体的后向散射。2014-2019年甚高频相干散射雷达连续不间断地对海南地区电离层E层至F层高度范围内的等离子体不规则体进行探测,从原始探测数据同相、正交相(I、Q)信号中实时计算出回波强度并上传至子午工程数据中心。通过这一数据可以得到我国低纬地区(海南)电离层场向不规则体发生率随太阳活动、季节和地方时的变化,以及电离层不规则体发生情况的逐日变化和暴时响应特征。本数据集能够为我国电离层物理领域内相关的研究、工程项目、空间天气预报提供数据支撑。 展开更多
关键词 相干散射雷达 低纬电离层 场向不规则体 准周期回波 扩展f 数据共享
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