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A Method for Risky Multiple Attribute Decision Making with Four - dimensional Reference Point
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作者 DUAN Mingyuan YAN Ruixia 《International English Education Research》 2016年第12期22-25,共4页
A method based on cumulative prospect theory was proposed to solve risky multiple attribute decision making problems with Four -dimensional reference points. Considering the influence of different learning processes a... A method based on cumulative prospect theory was proposed to solve risky multiple attribute decision making problems with Four -dimensional reference points. Considering the influence of different learning processes and corresponding features on decision-making, a new reference-learning behavior is added, and a risk-based multiple-attribute decision-making method based on four-dimensional reference point cumulative prospect theory is proposed. Firstly, according to the cumulative prospect theory, the prospect value and the decision function value of the four reference points of learning, time, evaluation value and expected value are calculated respectively, and the cumulative prospect value matrix of each program dynamic is formed. Secondly,according to the WAA operalor, Maximize the stage weighting model to obtain the integrated cumulative prospect value. Finally, on the basis of this, the alternatives are sorted according to the size of the total cumulative prospect value, and compared with other methods, the validity and scientific of the proposed method are proved. 展开更多
关键词 Risk multiple attribute decision making Cumulative Prospect Theory Four-dimensional reference point
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Quantum-Mechanical Information Content of Multiples Hartree-Fock Solutions. The Multi-Reference Hartree-Fock Configuration Interaction Method
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作者 Luiz Augusto Carvalho Malbouisson Antonio Moreira de Cerqueira Sobrinho Micael Dias de Andrade 《Journal of Modern Physics》 2014年第7期543-548,共6页
The Hartree-Fock equation is non-linear and has, in principle, multiple solutions. The ωth HF extreme and its associated virtual spin-orbitals furnish an orthogonal base Bω of the full configuration interaction spac... The Hartree-Fock equation is non-linear and has, in principle, multiple solutions. The ωth HF extreme and its associated virtual spin-orbitals furnish an orthogonal base Bω of the full configuration interaction space. Although all Bω bases generate the same CI space, the corresponding configurations of each Bω base have distinct quantum-mechanical information contents. In previous works, we have introduced a multi-reference configuration interaction method, based on the multiple extremes of the Hartree-Fock problem. This method was applied to calculate the permanent electrical dipole and quadrupole moments of some small molecules using minimal and double, triple and polarized double-zeta bases. In all cases were possible, using a reduced number of configurations, to obtain dipole and quadrupole moments in close agreement with the experimental values and energies without compromising the energy of the state function. These results show the positive effect of the use of the multi-reference Hartree-Fock bases that allowed a better extraction of quantum mechanical information from the several Bω bases. But to extend these ideas for larger systems and atomic bases, it is necessary to develop criteria to build the multireference Hartree-Fock bases. In this project, we are beginning a study of the non-uniform distribution of quantum-mechanical information content of the Bω bases, searching identify the factors that allowed obtain the good results cited 展开更多
关键词 multiple HARTREE-FOCK SOLUTIONS QUANTUM MECHANICAL INFORMATION Content MULTI-reference Hartre-Fock Configuration Interaction Method
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Theoretical Study on Divergence Problems of Single Reference Perturbation Theories
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作者 Jiang Yi Zhong-fu Xie Fei-wu Chen 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2019年第5期597-602,共6页
Divergences of the single reference perturbation theories due to the addition of diffusion basis functions have been investigated for both closed-shell and open-shell molecular systems. It is found that the oscillator... Divergences of the single reference perturbation theories due to the addition of diffusion basis functions have been investigated for both closed-shell and open-shell molecular systems. It is found that the oscillatory range of perturbation energies of open-shell systems increases as the spin multiplicity of systems changes from 2 to 4. Feenberg transformation is exploited to treat the divergence problems. It is found numerically that within the interval of Feenberg parameter there exists a minimum perturbation order at which the perturbation series become convergent. It is also found for the open-shell systems that the magnitude of the corresponding Feenberg parameter becomes larger as the spin multiplicity of the system of interest changes from 2 to 4. 展开更多
关键词 Single reference perturation theory DIVERGENCE Diffuse function Spin multiplicity Feenberg transformation
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Variations in Tomotherapy Beam Outputs: A Multiple-Institutional Investigation
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作者 Hidetoshi Shimizu Koji Sasaki +5 位作者 Kentaro Sugi Hiroshi Fukuma Tadashi Nakabayashi Taiki Isomura Hiroyuki Tachibana Takeshi Kodaira 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2018年第1期87-99,共13页
This study aimed to determine variations in tomotherapy beam outputs at multiple institutions. Measurements were obtained at 22 radiotherapy institutions. The first parameter was the absolute dose to water (Dfmsrw, Qm... This study aimed to determine variations in tomotherapy beam outputs at multiple institutions. Measurements were obtained at 22 radiotherapy institutions. The first parameter was the absolute dose to water (Dfmsrw, Qmsr) in the machine-specific reference field (fmsr), which indicated a static field in the tomotherapy reference conditions defined by the International Atomic Energy Agency (IAEA) study group. The second measured parameter was the difference between the measured and the planed doses in the intensity modulated radiotherapy (IMRT) verification plans, which were created using a solid phantom by the vendor during tomotherapy apparatus installation to adjust the beam output. The IMRT verification plan error at each institution was defined as the systematic error of the beam output;Dfmsrw, Qmsr was subsequently modified. The Dfmsrw, Qmsr values of four institutions with a modified energy fluence per ideal open time (EFIOT) were lower than the values at other institutions. The mean value of all institutions except those four was 0.994 ± 0.013 Gy (range: 0.974 Gy, 1.017 Gy). When the Dfmsrw, Qmsr value was corrected by the IMRT verification error, this variation decreased. In addition, the mean IMRT verification errors in the TomoDirectTM and TomoHelicalTM modes with the TomoEDGETM mode were 1.2% ± 0.8% (range: -0.6%, 1.8%) and 0.2% ± 0.5% (range: -0.6%, 0.9%), respectively (p 展开更多
关键词 TOMOTHERAPY Machine-Specific reference Field multiple Institutions BEAM OUTPUT
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正常成人电刺激痛感觉阈与耐痛阈相关性及影响因素的多元线性回归分析
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作者 余娅 李雪薇 +2 位作者 唐俊童 覃万翔 石英 《重庆医科大学学报》 CAS CSCD 北大核心 2024年第10期1125-1131,共7页
目的:测定正常成人在电刺激下的痛感觉阈(perception pain threshold,PTH)、耐痛阈(pain tolerance,PTO)水平,探讨影响因素,分析痛感觉阈、耐痛阈的关系,并建立正常成人的PTH、PTO参考值范围。方法:采用一元线性回归、多元线性回归分析... 目的:测定正常成人在电刺激下的痛感觉阈(perception pain threshold,PTH)、耐痛阈(pain tolerance,PTO)水平,探讨影响因素,分析痛感觉阈、耐痛阈的关系,并建立正常成人的PTH、PTO参考值范围。方法:采用一元线性回归、多元线性回归分析等方法,回顾性分析2017年10月21日至2020年5月22日在陆军军医大学第一附属医院疼痛科使用体感诱发电位测量仪系统进行电刺激测试的正常成人痛阈相关数据,性别、年龄、职业、学历、婚姻、月收入、体质指数(body mass index,BMI)等一般资料。计算正常成人PTH、PTO参考值范围。结果:一元线性回归分析显示PTH与PTO的变化呈高度正相关(P<0.001)。分别以PTH、PTO的值为因变量,将性别、年龄、职业、学历、婚姻、月收入、BMI指数为自变量进行多元线性回归分析,结果表明性别是PTH、PTO的影响因素(P<0.001),不同性别PTH、PTO值有明显差异。男性、女性PTH、PTO的值均呈正态分布(P均<0.05),采用正态分布法计算男性PTH、PTO的95%参考范围分别为0.051~4.388、1.845~13.012,女性PTH、PTO的95%参考范围分别为0.146~3.069、1.521~10.207;男性PTH、PTO的平均值±标准差分别为2.219±1.224,7.429±8.115,女性PTH、PTO的平均值±标准差分别为1.608±0.556,5.864±4.910。结论:疼痛的敏感性女性高于男性,女性PTH、PTO正常值范围均较男性窄。疼痛的感受性与耐受性高度正相关。 展开更多
关键词 疼痛 痛阈 多元线性回归 参考值 性别
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喷油润滑球轴承流动特性的数值研究
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作者 李慎龙 侯潇男 +1 位作者 张金乐 吴维 《北京理工大学学报》 EI CAS CSCD 北大核心 2024年第5期494-500,共7页
基于流体体积(VOF)方法建立了喷油润滑球轴承的数值仿真模型.分别采用滑移网格法和多重参考系(MRF)方法对轴承油气两相流动进行了数值计算,得到了轴承内部流场分布和搅油力矩.搭建了轴承流场可视化试验台,对比分析了仿真流场与高速摄影... 基于流体体积(VOF)方法建立了喷油润滑球轴承的数值仿真模型.分别采用滑移网格法和多重参考系(MRF)方法对轴承油气两相流动进行了数值计算,得到了轴承内部流场分布和搅油力矩.搭建了轴承流场可视化试验台,对比分析了仿真流场与高速摄影实测流场.结果表明:滑移网格下的轴承内部油液体积分数大于用MRF方法的计算结果,且当转速逐渐增大时,轴承内部油液体积分数均逐渐减小,且在离心力作用下,润滑油更多地分布在轴承外圈滚道.滑移网格下的轴承内部流场油液分布更接近实测流场.仿真计算的搅油力矩随转速增大而增大,MRF方法下搅油力矩大于滑移网格下的搅油力矩,平均误差约为12.3%.两种方法对搅油力矩的计算均具有较好的一致性,但MRF时间成本更低. 展开更多
关键词 流体体积 轴承 两相流 滑移网格 多重参考系 搅油力矩
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多源参考数据下的边坡DEM提取与精度分析
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作者 陈淑婷 夏益强 +1 位作者 陈兰兰 肖海平 《有色金属科学与工程》 CAS 北大核心 2024年第3期432-439,共8页
参考DEM是InSAR DEM提取精度分析中不可或缺的重要数据。考虑到当前可供使用的DEM数据层出不穷,如何选择可靠的参考DEM以解决不同地形DEM提取精度的需求,是DEM提取中一个亟待解决的问题。本文分别选择12.5 m的ALOS DEM、30 m的STRM DEM... 参考DEM是InSAR DEM提取精度分析中不可或缺的重要数据。考虑到当前可供使用的DEM数据层出不穷,如何选择可靠的参考DEM以解决不同地形DEM提取精度的需求,是DEM提取中一个亟待解决的问题。本文分别选择12.5 m的ALOS DEM、30 m的STRM DEM、90 m的STRM DEM作为参考DEM,依据2020年两景Sentinel-1A影像对德兴市部分地区边坡进行DEM数据提取,利用InSAR技术提取实验区的S1ADEM数据,并以ASTGTM DEM数据为参考,使用检测点法随机选择约300个检测点,选择相应的评价指标,分别对不同参考DEM下提取得到的S1ADEM进行精度检验。研究结果显示,使用12.5 m分辨率的ALOS DEM作为外部DEM,提取得到的S1ADEM精度更高,其在实验区A的RMSE为9.412 m,使用90 m的STRM DEM,提取得到的S1ADEM精度更低,其在实验区A的RMSE为10.293m。该实验为不同地形提取DEM提供了指导,能够帮助学者们在进行InSAR实验时更好地选择参考DEM,研究成果可为边坡灾害及预警提供重要的技术支持。 展开更多
关键词 多源参考数据 INSAR技术 DEM提取 精度分析
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基于D-I-M协同模型的企业数字化转型财务管理风险识别研究 被引量:1
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作者 魏延辉 曹文聪 陈娅茹 《甘肃科学学报》 2024年第2期131-137,146,共8页
数字化正在重塑经济发展的轨道,成为赋能经济增长新动力。精准识别财务管理风险中的关键指标及其相互关系,对企业更好地完成数字化转型尤为关键。融合企业人力、运营、财务、环境4个基本维度,从链式传导视角构建转型背景下企业财务管理... 数字化正在重塑经济发展的轨道,成为赋能经济增长新动力。精准识别财务管理风险中的关键指标及其相互关系,对企业更好地完成数字化转型尤为关键。融合企业人力、运营、财务、环境4个基本维度,从链式传导视角构建转型背景下企业财务管理风险指标体系。通过决策试验与评价实验室(DEMATL)法,分析各影响因素之间中心度和原因度关系,并利用解释结构模型(ISM),将矩阵进一步分析得到影响因素的层级划分,归纳影响因素之间的内在指向关系,最后运用交叉影响矩阵相乘(MICMAC)法计算各因素的驱动—依赖关系以判断其属性类别。提出通过D-I-M协同分析的方法,识别财务管理风险路径,为企业进行多链融合数字化转型、规避财务管理风险提供参考。 展开更多
关键词 决策试验与评价实验室法 解释结构模型 交叉影响矩阵相乘法 数字化转型 财务风险
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自适应剪枝的多参考有源控制算法
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作者 吴礼福 王绍博 +1 位作者 葛文昌 陈晨 《应用声学》 CSCD 北大核心 2024年第5期971-979,共9页
多参考信号有源控制算法是多噪声源环境噪声控制的研究热点之一。该文设计了Sigmoid函数加权的滤波最小均方算法,该算法不需要事先计算参考信号与误差信号的相关性以选取参考信号,而是在参考信号中引入自调整参数,通过调整该参数减小无... 多参考信号有源控制算法是多噪声源环境噪声控制的研究热点之一。该文设计了Sigmoid函数加权的滤波最小均方算法,该算法不需要事先计算参考信号与误差信号的相关性以选取参考信号,而是在参考信号中引入自调整参数,通过调整该参数减小无关信号对系统的影响。仿真实验对比验证了算法的两个优点:一是算法可以看作对每个参考信号采用了变步长的策略,二是算法可以依据参考信号与误差信号的相关性高低调整参考信号的权重,实现自适应剪枝的功能以降低系统的开销。 展开更多
关键词 主动噪声控制 FXLMS算法 车内噪声 多参考信号
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双标多测法在枣仁安神颗粒6个成分含量测定中的应用
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作者 陈颖 刘智勇 郑时桢 《海峡药学》 2024年第8期56-61,共6页
目的建立枣仁安神颗粒中斯皮诺素、6'''-阿魏酰斯皮诺素、迷迭香酸、五味子醇甲、五味子乙素和丹酚酸B 6个成分的双标多测法,验证该方法在枣仁安神颗粒质量评价中应用的准确性和可行性。方法采用HPLC法,以乙腈为流动相A,0.2... 目的建立枣仁安神颗粒中斯皮诺素、6'''-阿魏酰斯皮诺素、迷迭香酸、五味子醇甲、五味子乙素和丹酚酸B 6个成分的双标多测法,验证该方法在枣仁安神颗粒质量评价中应用的准确性和可行性。方法采用HPLC法,以乙腈为流动相A,0.2%冰醋酸溶液为流动相B,梯度洗脱,流速为1.0 mL·min^(-1),切换波长320 nm(斯皮诺素、6'''-阿魏酰斯皮诺素、迷迭香酸、丹酚酸B)、250 nm(五味子醇甲、五味子乙素),柱温28℃。采用5根不同的C_(18)色谱柱,测定枣仁安神颗粒6个成分的实际保留时间,计算各成分在各色谱柱保留时间的平均值,得到各成分的标准保留时间,选取斯皮诺素(峰1)、五味子乙素(峰6)作为双标化合物,使用双标线性校正法准确定位各成分色谱峰,预测成分在未知色谱柱的保留时间并进行方法学验证。以五味子乙素为参照物,计算其余各成分的相对校正因子,对各成分进行定量。结果双标线性校正法能够准确地预测待测组分在未知色谱柱上的保留时间;斯皮诺素、6'''-阿魏酰斯皮诺素、迷迭香酸、五味子醇甲和丹酚酸B相对于五味子乙素的相对校正因子分别为0.7342、0.6063、0.5664、0.9975及0.7773,其RSD均小于1%;各成分含量计算值和实测值无显著差异。结论双标多测法同时测定枣仁安神颗粒中6个成分可行且准确。 展开更多
关键词 枣仁安神颗粒 双标多测法 相对校正因子定量 斯皮诺素 五味子乙素 6-阿魏酰斯皮诺素 丹酚酸B 五味子醇甲 迷迭香酸
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涡桨发动机舱引射通风冷却数值研究
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作者 陈尧 单勇 张靖周 《航空计算技术》 2024年第1期76-81,共6页
以涡轮螺旋桨飞机的排气系统/短舱为研究对象,构建了机翼/机身/螺旋桨一体的发动机短舱仿真物理模型,采用多参考坐标系(MRF)法对螺旋桨滑流进行了模拟,并探究了不同排气管长度下发动机舱内的流动和换热情况。结果表明:在研究参数范围内... 以涡轮螺旋桨飞机的排气系统/短舱为研究对象,构建了机翼/机身/螺旋桨一体的发动机短舱仿真物理模型,采用多参考坐标系(MRF)法对螺旋桨滑流进行了模拟,并探究了不同排气管长度下发动机舱内的流动和换热情况。结果表明:在研究参数范围内,随排气管混合管段长度增加,在无滑流状态下,排气管中间环缝的引射流量上升18.3%,排气管末端环缝引射流量上升0.27 kg/s;在有滑流状态下,中间环缝引射流量保持在0.174 kg/s左右基本不变,末端环缝引射流量相对增加了35.8%,混合管段长度变化对末端环缝引射影响较大。排气管外管温度分布具有不对称性,滑流引入后,表面平均温度下降15 K,降幅4%;混合管段壁面温度受引射出口回流区和高温排气影响略有升高。 展开更多
关键词 涡桨发动机 排气引射 通风冷却 螺旋桨滑流 多参考坐标系
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猴耳环双标多测法及抗氧化、α-葡萄糖苷酶抑制活性成分快速筛选法的建立
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作者 吴嘉琳 李志超 +3 位作者 纪温铎 傅咏梅 张蜀 邓红 《中药材》 CAS 北大核心 2024年第2期390-397,共8页
目的:建立猴耳环中5个成分的双标多测法及其抗氧化、α-葡萄糖苷酶抑制活性成分的快速筛选法。方法:采用HPLC法,以双标线性校正法准确定位猴耳环中5个成分色谱峰,以没食子酸为参照物,计算没食子酸与其余4个成分的相对校正因子,对各成分... 目的:建立猴耳环中5个成分的双标多测法及其抗氧化、α-葡萄糖苷酶抑制活性成分的快速筛选法。方法:采用HPLC法,以双标线性校正法准确定位猴耳环中5个成分色谱峰,以没食子酸为参照物,计算没食子酸与其余4个成分的相对校正因子,对各成分进行定量,将所得结果与外标法进行比较。采用离线DPPH-HPLC法及亲和超滤液相联用法快速筛选猴耳环中具有抗氧化、α-葡萄糖苷酶抑制活性成分。结果:双标线性校正法相比于相对保留时间更能准确地预测待测组分在未知色谱柱上的保留时间;相对校正因子法和外标法结果的RSD<2.00%。采用离线DPPH-HPLC法及亲和超滤液相联用法可以快速筛选出猴耳环中7-没食子酰基特利色黄烷、杨梅苷等不同程度抗氧化活性和α-葡萄糖苷酶抑制活性的化合物。结论:该研究建立的双标多测同时测定猴耳环中5个成分的方法准确可行,采用离线DPPH-HPLC法及亲和超滤液相联用法能快速、灵敏、高通量筛选猴耳环中的抗氧化和α-葡萄糖苷酶抑制活性成分。 展开更多
关键词 猴耳环 双标多测法 离线DPPH-HPLC法 亲和超滤液相联用法
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Numerical Simulation of the Mechanical Stirring Process in a Tannin-Based Foaming Precursor Resin
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作者 Lan Huang Wenbin Yuan +2 位作者 Hisham Essawy Xiaojian Zhou Xinyi Chen 《Fluid Dynamics & Materials Processing》 EI 2024年第10期2219-2234,共16页
Tannin foam is a new functional material.It can be widely applied to the automobile industry,construction industry,and packaging industry due to its wide range of raw materials,renewable,easily degraded,low cost and a... Tannin foam is a new functional material.It can be widely applied to the automobile industry,construction industry,and packaging industry due to its wide range of raw materials,renewable,easily degraded,low cost and almost no pollution.Preparing tannin foam is a very complex process that includes high temperature,two phases,mechanical agitation,and phase change.To investigate the influence of the stirring velocity and paddle shape,simulation was calculated by making use of the volume of fluid(VOF)method and multiple reference frame(MRF)method in a three-dimensional flow field of tannin-based foaming precursor resin.The gas holdup and velocity magnitude were analysed with various conditions of mechanical velocities and paddle shape in the stirring flow field.The result shows the higher the velocity,the greater the disturbance and paddle shape between the eggbeater and the Rushton turbine,obviously the paddle shape of the eggbeater with a wider range of agitation,which can entrap more air into the tannin-based foaming precursor resin in a short time.Especially when the speed is 1500 rpm,the flow field of the Rushton turbine comes out of a ditch,which decreases the efficiency of mass transfer;there is less air to mix into the tannin-based foaming precursor resin,which causes unevenness.At the same time,the eggbeater shows the marvelous capability of hybrid as it has two vortexes and multiple cycles that make a difference from the Rushton turbine,which has only one vortex and two upper and lower loops;the structure makes the flow field more stable allowed evenness of flow field tannin-based foaming precursor resin.The results reveal that it is beneficial for tannin-based foaming precursor resin to use an eggbeater with a speed of 1500 rpm to reduce the consumption of resources while obtaining a uniform flow field. 展开更多
关键词 Tannin-based foaming precursor resin mechanical agitation numerical simulation volume of fluid(VOF) multiple reference frame(MRF)
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基于差分技术的北斗定位误差校正研究 被引量:1
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作者 梁东 张雪 冯茂秘 《无线互联科技》 2024年第11期17-19,共3页
文章针对北斗卫星导航系统定位精度和可靠性的优化问题,探讨了基于多基准站的差分定位技术优化方法。文章对北斗卫星导航系统的定位原理和传统差分定位技术进行了深入研究,研究了基于多基准站的差分定位技术,并利用MATLAB的Navigation T... 文章针对北斗卫星导航系统定位精度和可靠性的优化问题,探讨了基于多基准站的差分定位技术优化方法。文章对北斗卫星导航系统的定位原理和传统差分定位技术进行了深入研究,研究了基于多基准站的差分定位技术,并利用MATLAB的Navigation Toolbox进行了实验验证。实验结果表明,多基准站差分技术在定位精度和可信度上均优于传统差分技术。 展开更多
关键词 北斗定位 差分技术 多基准站 性能优化
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多重参考系动区域比率变化对流场模拟的影响
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作者 岳相丞 石艳 +1 位作者 廖映华 赵练 《计算机仿真》 2024年第8期309-314,共6页
采用CFD软件在稳态计算复杂模型时,发现使用多重参考系分析固液两相流常常会出现计算结果不收敛的问题。在不改变数值模型边界条件的情况下,调整多重参考系动区域比率的取值,将搅拌固液两相的PY平直叶圆盘涡轮搅拌釜按不同比率划分了20... 采用CFD软件在稳态计算复杂模型时,发现使用多重参考系分析固液两相流常常会出现计算结果不收敛的问题。在不改变数值模型边界条件的情况下,调整多重参考系动区域比率的取值,将搅拌固液两相的PY平直叶圆盘涡轮搅拌釜按不同比率划分了20组,分析其动区域不同比率划分对稳态计算的收敛性、搅拌器的流场速度分布、固体颗粒体积分数分布、悬浮状态及搅拌器功率等结果的影响。结果表明:动区域比率β取值小于1.4时,计算不收敛,增大动区域比率能提高模型计算的收敛性。随着动区域比率增大,计算出的标准浓度差最大值与最小值的误差超过10%,速度与力矩的最大值与最小值误差都未超过2%,即动区域比率变化对模拟出的标准浓度差影响较大,对速度分布、搅拌器功率的影响较小。 展开更多
关键词 圆盘涡轮式搅拌器 收敛性 数值模拟 多重参考系
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A multiple transistor combination low-voltage curvature-corrected bandgap reference 被引量:4
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作者 苏凯 龚敏 +1 位作者 秦怀斌 孙晨 《Journal of Semiconductors》 EI CAS CSCD 2013年第6期152-156,共5页
A new bandgap reference(BGR) curvature compensation technology is proposed,which is a kind of multiple transistor combination.On the basis of the existing first-order bandgap reference technology,a compensation curr... A new bandgap reference(BGR) curvature compensation technology is proposed,which is a kind of multiple transistor combination.On the basis of the existing first-order bandgap reference technology,a compensation current circuit consisting of a sink current branch and a source current branch is added.The BGR was designed and simulated by using Semiconductor Manufacturing International Corporation(SMIC) 0.18μm CMOS process.The simulation results showed that when the power supply voltage was 1 V,the temperature coefficient of the BGR was 2.08 ppm/℃with the temperature range from—40 to 125℃,the power supply rejection ratio (PSRR) was—64.77 dB and the linear regulation was 0.44 mV/V with the supply power changing from 0.85 to 1.8 V. 展开更多
关键词 bandgap reference temperature coefficient multiple transistor combination PSRR line regulation
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Radiometric Cross-Calibration for Multiple Sensors with the Moon as an Intermediate Reference 被引量:1
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作者 Lu ZHANG Peng ZHANG +4 位作者 Xiuqing HU Lin CHEN Min MIN Na XU Ronghua WU 《Journal of Meteorological Research》 SCIE CSCD 2019年第5期925-933,共9页
The instrument cross-calibration is an effective way to assess the quality of satellite data. In this study, a new method is proposed to cross-calibrate the sensors among satellite instruments by using a RObotic Lunar... The instrument cross-calibration is an effective way to assess the quality of satellite data. In this study, a new method is proposed to cross-calibrate the sensors among satellite instruments by using a RObotic Lunar Observatory(ROLO) model and Apollo sample reflectance in reflective solar bands(RSBs). The ROLO model acts as a transfer radiometer to bridge between the instruments. The reflective spectrum of the Apollo sample is used to compensate for the difference in the instrument's relative spectral responses(RSRs). In addition, the double ratio between the observed lunar irradiance and the simulated lunar irradiance is used to reduce the difference in instrument lunar viewing and illumining geometry. This approach is applied to the Moderate Resolution Imaging Spectroradiometer(MODIS), the Sea-Viewing Wide Field-of-View Sensor(Sea Wi FS), and the Advanced Land Imager(ALI) on board three satellites, respectively. The mean difference between MODIS and Sea Wi FS is less than 3.14%, and the difference between MODIS and ALI is less than 4.75%. These results indicate that the proposed cross-calibration method not only compensates for the RSR mismatches but also reduces the differences in lunar observation geometry. Thus,radiance calibration of any satellite instrument can be validated with a reference instrument bridged by the moon. 展开更多
关键词 radiometric CROSS-CALIBRATION multiple SENSORS CALIBRATION reference
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Feasibility study of phase-sensitive imaging based on multiple reference optical coherence tomography 被引量:1
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作者 Roshan Dsouza Hrebesh Subhash +4 位作者 Kai Neuhaus Paul M.McNamara Josh Hogan Carol Wilson Martin J.Leahy 《Chinese Optics Letters》 SCIE EI CAS CSCD 2017年第9期25-30,共6页
Multiple reference optical coherence tomography(MR-OCT) is a recently developed, low-cost and compact time-domain OCT solution for primary care and consumer level applications. A combination of a voice coil actuator... Multiple reference optical coherence tomography(MR-OCT) is a recently developed, low-cost and compact time-domain OCT solution for primary care and consumer level applications. A combination of a voice coil actuator and a partial mirror(PM) extends the scan range for imaging depths of approximately 1 mm in biological samples. Our previous research on MR-OCT is based only on intensity information obtained from the depth-resolved interference signal. In this Letter, we extract the phase information from the MR-OCT signal and, hence, provide an additional contrast modality. The phase sensitivity of the system is measured to be approximately 0.2 and 1.5 rad for the first and twelfth orders of reflection when using a mirror as the sample.This Letter describes first results of phase-sensitive data measured on a phantom obtained with MR-OCT. Data from a chick embryo chorioallantoic membrane(CAM) is used to demonstrate the feasibility of MR-OCT for in vivo phase-sensitive imaging. 展开更多
关键词 Feasibility study of phase-sensitive imaging based on multiple reference optical coherence tomography VCM Figure CAM
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车内路噪主动控制系统参考传感器布放方法 被引量:1
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作者 贺岩松 刘亚琪 +2 位作者 夏子恒 张志飞 周桃 《振动.测试与诊断》 EI CSCD 北大核心 2023年第4期669-676,826,共9页
由于合理布放参考传感器是车内路噪主动控制(road noise cancellation,简称RNC)系统的关键,提出了基于多重相干分析(multiple coherence analysis,简称MCA)法的参考传感器布置方法,结合多通道归一化滤波x最小均方(normalized filter-x l... 由于合理布放参考传感器是车内路噪主动控制(road noise cancellation,简称RNC)系统的关键,提出了基于多重相干分析(multiple coherence analysis,简称MCA)法的参考传感器布置方法,结合多通道归一化滤波x最小均方(normalized filter-x least mean square,简称NFxLMS)算法,建立基于MCA的参考信号选取数学模型,选取具有最大多重相干系数的布放位置,采用截断奇异值分解法提高多重相干系数的计算精度,并使用遗传算法进行多重相干法布放结果寻优。针对某电动汽车进行了车内路噪主动控制的仿真分析和实车道路试验。结果表明,所提出的参考信号布放方法有利于提升车内路噪主动控制系统的降噪效果。 展开更多
关键词 路噪主动控制 参考信号 多重相干法 遗传算法
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基于ISM-MICMAC的煤矿工人违章行为影响因素研究 被引量:3
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作者 王天瑜 春思帆 《煤矿安全》 CAS 北大核心 2023年第7期260-264,共5页
为探究煤矿工人违章行为影响因素及其相互作用关系,建立了违章行为影响因素指标体系,并采用解释结构模型(ISM)和交叉影响矩阵相乘法(MICMAC),深入剖析了影响因素之间的逻辑关系,构建了影响因素的多级递接结构模型及驱动力-依赖度象限分... 为探究煤矿工人违章行为影响因素及其相互作用关系,建立了违章行为影响因素指标体系,并采用解释结构模型(ISM)和交叉影响矩阵相乘法(MICMAC),深入剖析了影响因素之间的逻辑关系,构建了影响因素的多级递接结构模型及驱动力-依赖度象限分类图。结果表明:煤矿工人违章行为影响因素可划分为4级3阶的多级递接结构;安全知识技能、安全意识水平、安全行为习惯、自保互保意识属于依赖簇,具有强依赖性,是影响违章行为的重要因素;安全生产投入、安全管理制度、矿领导安全理念、管理者安全意识、企业安全氛围属于独立簇,具有强驱动力,是影响违章行为的关键因素。 展开更多
关键词 煤矿工人 违章行为 影响因素 解释结构模型 交叉影响矩阵相乘法 驱动力 依赖度
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