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GNSS gyroscopes:determination of angular velocity and acceleration with very high-rate GNSS

Satellite Navigation 2024年第1期5卷 74-90页

作者： Yun Shi Peiliang Xu Yuanming Shu xiaolin Meng School of Geomatics Xi’an University of Science and TechnologyXi’an710054People’s Republic of China Disaster Prevention Research Institute Kyoto UniversityUjiKyoto611-0011Japan College of Marine Geosciences Ocean University of ChinaQingdaoPeople’s Republic of China School of Instrument Science and Engineering Southeast UniversityNanjing210096People’s Republic of China

Although global navigation satellite systems(GNSS)have been routinely applied to determine attitudes,there exists no literature on determining angular velocity and/or angular acceleration from *** by the invention of computerized accelerometers of the correspondence author and following the success of accurately recovering translational velocity and acceleration waveforms from very high-rate GNSS precise positioning by Xu and his collaborators in 2021,we propose the concept of GNSS gyroscopes and reconstruct angular velocity and acceleration from very high-rate GNSS attitudes by applying regularization under the criterion of minimum mean squared *** major results from the experiments can be summarized in the following:(i)angular velocity and acceleration waveforms computed by applying the difference methods to high-rate GNSS attitudes are too noisy and can be physically not meaningful and numerically *** same can be said about inertial measurement unit(IMU)attitudes,if IMU gyros are not of very high accuracy;(ii)regularization is successfully applied to reconstruct the high-rate angular velocity and acceleration waveforms from 50 Hz GNSS attitudes and significantly outperforms the difference methods,validating the proposed concept of GNSS *** comparing the angular velocity and acceleration results by using the difference methods and regularization,we find that the peak values of angular velocity and acceleration by regularization are much smaller by a maximum factor of 1.57 in the angular velocity to a maximum factor of 8662.53 times in the angular acceleration in the case of high-rate GNSS,and by a maximum factor of 1.26 in the angular velocity to a maximum factor of 2819.85 times in the angular acceleration in the case of IMU,respectively;and(iii)the IMU attitudes apparently lead to better regularized angular velocity and acceleration waveforms than the high-rate GNSS attitudes,which can well be explained by the fact that the

关键词： Angular velocity Angular acceleration High-rate GNSS GNSS attitudes GNSS gyroscopes Regularization

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How Does the Government Facilitate the Co-Production of Digital Public Safety Services?——Based on Empirical Evidence from Shenzhen

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Social Sciences in China 2024年第2期45卷 113-134页

作者： Wu xiaolin zhou Enlai School of Government Nankai University

The application of big data technology provides support for the co-production of public safety *** research often focuses on how technology influences co-production,but lacks attention to the key actors that drive co-production and the mechanisms that facilitate *** study examines the role of government in the digital co-production of public safety services,using the practice of Shenzhen as a case *** has built 125 information systems based on over 100 billion pieces of big data,forming a model of digital safety service *** study reveals three types of digital co-production,characterized by"government-business joint planning,passive participation of businesses and the public,and active cooperation among government,businesses,and the public"in the"design-production-application"*** study shows that the government is not only a co-producer but also a proactive actor in activating the willingness of non-governmental entities to *** governments mobilize non-governmental participation through three mechanisms:empowerment,profit enhancement,and value ***"power-interest-value"paradigm is applicable for analyzing the co-production of public services and helps to explain the transformation mechanisms of co-production behavior.

关键词： public safety co-production smart emergency response digital public safety

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基于CEEMD-SBO-LSSVR的超短期风电功率组合预测

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电网技术 2021年第3期45卷 855-862页

作者：周小麟童晓阳西南交通大学电气工程学院四川省成都市610031

为提高风电功率预测的精度,提出了一种基于互补集合经验模态分解(complementary ensemble empirical mode decomposition,CEEMD)、缎蓝园丁鸟优化算法(satinbower birdoptimizationalgorithm,SBO)及最小二乘支持向量回归(least squares support vector regression,LSSVR)模型的超短期风电功率组合预测方法。针对风电序列的随机波动性,采用CEEMD对风电功率序列进行分解,将分解得到的不同特征尺度的各分量作为LSSVR模型的训练输入量。引入SBO算法对LSSVR的正则化参数与核函数宽度进行优化,建立各分量的预测模型,将各分量的预测输出值叠加得到最终的风电功率预测值。所提CEEMD-SBO-LSSVR组合预测方法不仅有效降低了预测的复杂度,而且保证原始风电序列经模态分解处理后具有小的重构误差。仿真结果表明,与其他预测模型相比,所提方法具有较高的超短期风电功率预测精度。

关键词：超短期风电预测最小二乘支持向量回归互补集合经验模态分解缎蓝园丁鸟优化算法组合模型

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Monophase-homointerface electrodes intrinsically stabilize high-voltage all-solid-state batteries

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Science China Chemistry 2024年第5期67卷 1729-1739页

作者： xiaolin Xiong Xianguo Ma Tianshi Lv Liquan Chen Liumin Suo Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of ScienceBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

The electrochemical stability and contact reliability of heterointerfaces between the solid electrolyte(SE) and electrode are critical for all-solid-state batteries(ASSBs), particularly much more challenging for high-voltage ASSBs, owing to the limited thermodynamically electrochemical window and mechanical inflexibility of SE, aggravating interfacial side reactions and contact failure. Considering all those issues originating from intrinsic heterogeneity in physicochemical features between the cathode material and SE, we are thinking about simplifying the heterointerfaces into a homointerface as a permanent cure to solve all electrochemical-mechanical interfacial failure. Herein, we propose monophase cathodes to construct thermodynamically stable all-in-one homointerfaces in ASS electrodes, removing unstable heterointerfaces by excluding SEs and intrinsically eliminating the Li chemical potential gap to avoid the formation of lithium-depleted space-charge layer and highly resistive mixed ion–electron conductor interphase. Our conception is successfully validated in the layered transition-metal oxide cathodes, which display outstanding stability no matter the MH-LiCoO_(2) cathode charging to 4.7 V or MH-Li_(1.2)Mn_(0.54)Ni_(0.13)-Co_(0.13)O_(2) cathode charging to 5.3 V. It is undeniable that our current version of above-illustrated MH-cathodes would bring out some new challenges for the practical application due to abandoning the SE. However, we believe our work also offers a brandnew direction to ultimately address the electrochemical–mechanical interfacial issues that would be promising for high-energy ASSBs with more discoveries of advanced monophase cathodes in the future.

关键词： monophase-homointerface electrode high-voltage all-solid-state batteries electrochemical-mechanical interfacial issue

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Heat Recuperation for the Self-Condensing CO_(2)Transcritical Power Cycle

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Journal of Thermal Science 2024年第5期33卷 1630-1641页

作者： PAN Lisheng SHI Weixiu SUN Yin SUN Yiwei WEI xiaolin State Key Laboratory of High-temperature Gas Dynamics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Environment and Energy Engineering Beijing University of Civil Engineering and ArchitectureBeijing 100044China

The supercritical CO_(2)Brayton cycle has potential to be used in electricity generation occasions with its advantages of high efficiency and compact *** on a so-called self-condensing CO_(2)transcritical power cycle,a model was established and four different layouts of heat recuperation process were analyzed,a without-recuperation cycle,a post-recuperation cycle,a pre-recuperation cycle and a re-recuperation *** results showed that the internal normal cycle's share of the whole cycle increases with increasing the cooling pressure and decreasing the final cooled *** load in the supercritical heater decreases with increasing the cooling *** perspective of performance,the re-recuperation cycle and the pre-recuperation cycle have similar thermal efficiency which is much higher than other two *** thermal efficiency and net power output have a maximum value with the cooling pressure,except in the condition with the final cooled temperature of 31℃.Considering both the complexity and the economy,the pre-recuperation cycle is more applicable than the other *** 35℃of the final cooled temperature,the thermal efficiency of the pre-recuperation cycle reaches the peak 0.34 with the cooling pressure of 8.4 MPa and the maximum net power output is 2355.24 kW at 8.2 MPa of the cooling pressure.

关键词： CO_(2)transcritical power cycle heat recuperation process self-condensing

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学位论文利用现状引发的思考

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学位与研究生教育 2005年第7期 48-51页

作者：周晓林中国矿业大学档案馆徐州 221008

针对学位论文利用现状,对学位论文的著作权人问题、著作权保护问题及合理使用问题等进行了思考。

关键词：学位论文著作权合理使用高校

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压裂投产不压井作业一体化管柱

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钻采工艺 2020年第4期43卷 54-56,60,I0004页

作者：周小林中国石化东北油气分公司有效储层改造技术攻关项目团队

为解决高压油气井在传统压裂投产过程中,因压井对地层造成伤害以及地面带压作业成本高等问题,针对空井筒压裂自身特点,开展了以井下控制为主的不压井完井投产及配套工艺研究,通过预埋在井下的关键封堵装置成功解决了不压井换装井口、起... 详细信息

为解决高压油气井在传统压裂投产过程中,因压井对地层造成伤害以及地面带压作业成本高等问题,针对空井筒压裂自身特点,开展了以井下控制为主的不压井完井投产及配套工艺研究,通过预埋在井下的关键封堵装置成功解决了不压井换装井口、起下生产管柱等技术难题。通过现场11口井试验应用,一次作业成功率100%,达到了保护储层、安全、清洁、经济、高效开发天然气井的目的,为国内其他油气田开展不压井投产作业提供了较好的经验,应用前景广阔。

关键词：压裂投产不压井作业井下可控一体化管柱

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Fast Two-dimensional Positioning Method of Crab Pulsar Based on Multiple Optimization Algorithms

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Research in Astronomy and Astrophysics 2024年第10期24卷 92-103页

作者： Jianfeng Chen Jin Liu Xin Ma xiaolin Ning College of Information Science and Engineering Wuhan University of Science and TechnologyWuhan 430081China School of Instrumentation Science and Opto-electronics Engineering Beihang UniversityBeijing 100191China Hefei National Laboratory Hefei 230088China

In the two-dimensional positioning method of pulsars, the grid method is used to provide non-sensitive direction and positional estimates. However, the grid method has a high computational load and low accuracy due to the interval of the grid. To improve estimation accuracy and reduce the computational load, we propose a fast twodimensional positioning method for the crab pulsar based on multiple optimization algorithms(FTPCO). The FTPCO uses the Levenberg–Marquardt(LM) algorithm, three-point orientation(TPO) method, particle swarm optimization(PSO) and Newton–Raphson-based optimizer(NRBO) to substitute the grid method. First, to avoid the influence of the non-sensitive direction on positioning, we take an orbital error and the distortion of the pulsar profile as optimization objectives and combine the grid method with the LM algorithm or PSO to search for the non-sensitive direction. Then, on the sensitive plane perpendicular to the non-sensitive direction, the TPO method is proposed to fast search the sensitive direction and sub-sensitive direction. Finally, the NRBO is employed on the sensitive and sub-sensitive directions to achieve two-dimensional positioning of the Crab pulsar. The simulation results show that the computational load of the FTPCO is reduced by 89.4% and the positioning accuracy of the FTPCO is improved by approximately 38% compared with the grid method. The FTPCO has the advantage of high real-time accuracy and does not fall into the local optimum.

关键词： (stars:)pulsars:individual(Crab pulsar) space vehicles methods:data analysis astrometry

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从知觉负载理论来理解选择性注意

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心理科学进展 2005年第4期13卷 413-420页

作者：魏萍周晓林北京大学心理学系北京100871

知觉负载理论被认为解决了选择性注意研究的早选择和晚选择观点之争。当前任务对注意资源的耗用程度决定了与任务无关的干扰刺激得到多少加工,从而导致在低知觉负载下,注意资源自动溢出去加工干扰刺激(晚选择),而在高知觉负载下,注意资... 详细信息

知觉负载理论被认为解决了选择性注意研究的早选择和晚选择观点之争。当前任务对注意资源的耗用程度决定了与任务无关的干扰刺激得到多少加工,从而导致在低知觉负载下,注意资源自动溢出去加工干扰刺激(晚选择),而在高知觉负载下,注意资源被当前任务耗尽而无法加工干扰刺激(早选择)。知觉负载理论提出后,研究者进行了一系列研究。一部分工作专注于知觉负载对选择性注意的调节作用;另外一些工作则关注其他认知过程如何影响注意资源的分配,其中知觉负载与工作记忆负载的关系是当前关注重点。

关键词：知觉负载选择性注意早选择晚选择干扰控制

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音乐之脑

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心理科学进展 2006年第5期14卷 641-647页

作者：叶铮周晓林北京大学心理学系北京100871

回顾并总结了近年来对音乐认知神经基础的研究结果,包括人类感知乐曲的音高、理解音乐的结构和意义中的脑基础,音乐家和普通人在音乐认知上的脑功能差异,以及东西方听众在聆听本土和非本土音乐时的脑活动差异,并对国内利用脑功能成像技... 详细信息

回顾并总结了近年来对音乐认知神经基础的研究结果,包括人类感知乐曲的音高、理解音乐的结构和意义中的脑基础,音乐家和普通人在音乐认知上的脑功能差异,以及东西方听众在聆听本土和非本土音乐时的脑活动差异,并对国内利用脑功能成像技术和事件相关电位技术研究音乐认知的前景作出展望。

关键词：音乐认知神经基础 fMRI ERP

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