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火电厂输煤系统模糊统计方法的研究

清华大学学报（自然科学版） 1998年第5期38卷 59-63页

作者：王炜裘炯程爱平李兰馨清华大学热能工程系

为解决目前国内已有的燃煤计量系统普遍存在着计量模型粗糙、系统通用性不强、计量精确度不高的缺陷的问题，以萧山发电厂输煤程控工程为背景，构建出了一套完整的计量系统。本系统充分利用现有的设备，特别是现有的电子皮带秤计量装置... 详细信息

为解决目前国内已有的燃煤计量系统普遍存在着计量模型粗糙、系统通用性不强、计量精确度不高的缺陷的问题，以萧山发电厂输煤程控工程为背景，构建出了一套完整的计量系统。本系统充分利用现有的设备，特别是现有的电子皮带秤计量装置，采用先进的计算机控制技术，自动采集电子皮带秤的计量脉冲，再结合加仓过程中相关设备的状态，进行合理的判断、处理，以此来实现燃煤分炉过程的准确计量。为提高系统计量的精确度，将模糊理论运用于燃煤计量算法。利用模糊数学的隶属度概念，可以更好地描述输煤的实际过程，尤其是在状态发生切换时刻的燃煤分配过程。仿真计算证明这一方法是有效而且可行的。

关键词：输煤系统模糊统计火电厂

Review of current ZT>1 thermoelectric sulfides

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Journal of Materiomics 2024年第1期10卷 218-233页

作者： Fu-Hua Sun Hezhang Li Jun Tan Lingmei Zhao Xinyu wang Haihua Hu Chao wang Takao Mori School of Materials Science and Engineering Hubei Normal UniversityHuangshi435002China International Center for Materials Nanoarchitechtonics(WPI-MANA) National Institute for Materials Science(NIMS)Namiki 1-1Tsukuba305-0047Japan department of precision Instrument Tsinghua UniversityBeijing100084China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China Graduate School of Pure and Applied Sciences University of TsukubaTsukuba305-8671Japan Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory Foshan528225China

Thermoelectrics has played a fascinating role in the developments of direct energy conversion *** the past decade,sulfur-based thermoelectric materials have been significantly advanced in optimizing electrical and thermal transport due to their similarities in chemical and structural properties with tellurides and *** review provides research progress on metal sulfides,particularly focuses on materials exhibiting high thermoelectric figure of merit(ZT>1.0).It highlights the potential compounds,***-S,Sn-S,Pb-S based,and *** strategies of superionic conducting,band configuration tuning,high-entropy alloying,and anomalous harmonic scattering are try to demonstrate the performance-improved mechanisms for thermoelectric *** addition,some common synthesis recipes are briefly introduced,and thereby making potential candidates as excellent alternatives for producing thermoelectric power generators in the mid *** outcomes along with how to further improve the thermoelectric performance and promote its scale-up applications are also outlined at the end.

关键词： Synthetic technology Figure merit of ZT Sulfides Thermoelectric

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石英晶体谐振器的力—频效应及其应用

清华大学学报（自然科学版） 1998年第8期38卷 35-38页

作者：冯冠平王晓红王劲松清华大学精密仪器及机械学系

自从石英晶体谐振器被发现以来，其力—频效应在实验和理论方面已经进行了半个世纪的研究，一系列有价值的理论和实验结果，使得基于力—频效应的传感器的发展具有可靠的理论基础。直到现在，力—频效应的意义，尤其是它在实际应用方面... 详细信息

自从石英晶体谐振器被发现以来，其力—频效应在实验和理论方面已经进行了半个世纪的研究，一系列有价值的理论和实验结果，使得基于力—频效应的传感器的发展具有可靠的理论基础。直到现在，力—频效应的意义，尤其是它在实际应用方面的意义还未消逝。本文以石英谐振器的力—频效应为主线，综述了其５０年来的研究概况及基于力—频效应的传感器的研究与发展。对在前人研究的基础上进行力—频效应的实际应用的进一步研究非常有意义。

关键词：石英谐振器力-频效应传感器石英晶体振荡器

Quantitative geochemical reconstruction of Eocene paleoenvironment in Fushun Basin,northeast china

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Acta Geochimica 2024年第3期43卷 571-587页

作者： Yuanji Li Pingchang Sun Qiang Zhang Junxian wang department of Safety Engineering Heilongjiang University of Science and TechnologyHarbin 150022China National Professional Center Lab of Safety Basic Research for Hydrocarbon Gas Pipeline Transportation Network Harbin 150022China College of Earth Sciences Jilin UniversityChangchun 130061JilinChina beijing Research Institute of Uranium Geology Beijing 100029China

The quantitative estimation of key parameters of paleotemperature and paleoprecipitation is crucial for paleoclimate *** data from mod-ern sediments are highly consistent with climate data,and their relationship can provide an important reference for the quantitative reconstruction of the *** this study,detailed inorganic geochemical analysis was carried out using high-precision sampling of the Paleogene(LFD-1 well)Guchengzi,Jijuntun and Xiloutian Formations in the Fushun Basin located in the mid-latitudes of the Northern *** Eocene Guchengzi Formation(54.51–47.8 Ma)and Jijuntun Formation(47.8–41.2.Ma)in the Fushun Basin were found to have been deposited under a humid *** lower(41.2.40.1 Ma)and upper(40.1–37.8 Ma)parts of the Xiloutian Formation were character-ized by semiarid and semihumid–semiarid climates,respec-tively,which is very similar to the paleoclimatic information reflected by organic carbon *** Eocene Thermal Maximum 2.ETM2.~53.7 Ma),Early Eocene Climatic Optimum(EECO,~53.1–46.5 Ma),Eocene Thermal Maxi-mum 3(ETM 3,~52.8 Ma),and Middle Eocene Climatic Optimum(MECO,~40.7–40.1 Ma)events significantly enhanced chemical weathering during these *** rapid increase in pCO_(2.concentration leads to an increase in temperature,precipitation,and surface runoff,exhibiting strong chemical *** mean annual temperature(MATa)and mean annual precipitation(MAPa,MAPb,and MAPc)were estimated using parameters,such as the corrosion index without potassium(CIA-K),CaO/Al_(2.O_(3),and(Na_(2.O+K_(2.O)/Al_(2.O_(3).Comparing MAPa,MAPb,and MAPc with the MAP estimated using pollen data,MAPa and MAPb were found to be more sensitive to the climate during high precipitation periods(precipitation>1000 mm,Guchengzi Formation),and the recovered average precipi-tation was similar to *** contrast,MAPc was more sensitive to the climate during low precipitation periods(precipitation<1000 mm,Jijuntun,and Xilouti

关键词： Eocene Fushun Basin Major element Paleoclimate Geochemical reconstruction

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模型直升机航向系统辨识中的加权判据

系统仿真学报 2003年第5期15卷 646-648,673页

作者：陈皓生陈大融汪家道清华大学精密仪器与机械学系北京100084

在进行模型直升机航向运动的系统辨识时,由于人工操纵对实验数据影响,需要使用多次实验数据进行系统辨识。为增强实验数据中所包含的动力学信息,并减少被噪声破坏的数据对系统辨识结果的影响,采用了带有加权判据的最小二乘参数估计方法... 详细信息

在进行模型直升机航向运动的系统辨识时,由于人工操纵对实验数据影响,需要使用多次实验数据进行系统辨识。为增强实验数据中所包含的动力学信息,并减少被噪声破坏的数据对系统辨识结果的影响,采用了带有加权判据的最小二乘参数估计方法。在计算加权判据中的权值因子时,采用了单个神经元对权值进行自动分配。辨识结果表明,基于带有加权判据的最小二乘方法所得的航向动力学模型能较好地吻合实际的航向输出。该方法亦是处理多次实验数据的一种有效方法。

关键词：直升机建模系统辨识神经网络多实验数据处理

Micro sensors based on Planar Microtoroid cavities

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Micro sensors based on Planar Microtoroid cavities

Kinematic calibration method with high measurement efficiency and robust identification for hybrid machine tools

2.08 International Conference on Optical Instruments and Technology

作者： Jijun XIONG~a,Yingzhan YAN~a,Zhe JI~a,Shaohui wang~a,Shubin YAN~(*a,b), Xiongying Ye~b,Zhaoying Zhou~b,Wendong ZHANG~a a National Key Laboratory For Electronic Measurement Technology,North university Of{2., Taiyuan,china 030051 b State Key Laboratory of precision Measurement Technology and Instruments,department of precision Instruments and Mechanology,tsinghua university,beijing,china 100084

Planar Microtoroid cavities with ultrahigh quality factor have very strong confined function to the electromagnetic wave coupled into them due to their novel ring-like ***,they have very good applications in high sensitivity sensors and other micro optics *** this paper,the Planar Microtoroid cavity and its coupling system constructed together with the tapered fiber are ***,micro sensors based on the above coupling system are *** sensors measure environmental parameters by means of monitoring the changes in the transmission spectrum of the high finesse Planar Microtoroid cavities,obtaining fine resolution and high accuracy due to their ultrahigh quality factor(Q)*** sensitive mechanism and the feasibility are demonstrated through optical and mechanical software *** software BeamPROP,the evident resonance and strengthened phenomenon to the electromagnetic wave coupled into the micro-cavity are shown,which have a big relation with the light frequency. The results indicate that,Planar Microtoroid cavity is very promising in designing new micro sensors.

关键词： Planar Microtoroid cavity coupling system micro sensor sensitivity

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Chinese Journal of Aeronautics 2024年第3期37卷 468-482页

作者： Liping wang Mengyu LI Guang YU Weitao LI Xiangyu KONG State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China beijing Key Laboratory of precision/Ultra-precision Manufacturing Equipment and Control Beijing 100084China

Geometric error is the main factor affecting the machining accuracy of hybrid machine *** calibration is an effective way to improve the geometric accuracy of hybrid machine *** necessity to measure both position and orientation at each pose,as well as the instability of identification in case of incomplete measurements,severely affects the application of traditional calibration *** this study,a kinematic calibration method with high measurement efficiency and robust identification is proposed to improve the kinematic accuracy of a five-axis hybrid machine ***,the configuration is introduced,and an error model is ***,by investigating the mechanism error characteristics,a measurement scheme that only requires tool centre point position error measurement and one alignment operation is ***,by analysing the effects of unmeasured degrees of freedom(DOFs)on other DOFs,an improved nonlinear least squares method based on virtual measurement values is proposed to achieve stable parameter identification in case of incomplete measurement,without introducing additional ***,the proposed calibration method is verified through simulations and *** proposed method can efficiently accomplish the kinematic calibration of the hybrid machine *** accuracy of the hybrid machine tool is significantly improved after calibration,satisfying actual aerospace machining requirements.

关键词： Hybrid machine tool Calibration Measurement scheme Improved nonlinear least squares method Virtual measurement values

A real-time performance improvement method for composite time scale

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Chinese Physics B 2024年第9期33卷 350-357页

作者： Fangmin wang Wenlin Li Hongfei Dai Chunyi Li Jianhua Zhou Shenhui Xue Bo wang State Key Laboratory of precision Space–time Information Sensing Technology Department of Precision InstrumentTsinghua UniversityBeijing 100084China Key Laboratory of Photonic Control Technology(tsinghua university) Ministry of EducationBeijing 100084China beijing Satellite Navigation Center Beijing 100094China

The composite time scale(CTS)provides a stable,accurate,and reliable time scale for modern *** improvement of CTS’s real-time performance will improve its stability,which strengths related applications’*** at this goal,a method achieved by determining the optimal calculation interval and accelerating adjustment stage is proposed in this *** determinants of the CTS’s calculation interval(characteristics of the clock ensemble,the measurement noise,the time and frequency synchronization system’s noise and the auxiliary output generator noise floor)are studied and the optimal calculation interval is *** also investigate the effect of ensemble algorithm’s initial parameters on the CTS’s adjustment stage.A strategy to get the reasonable initial parameters of ensemble algorithm is *** results show that the adjustment stage can be finished rapidly or even can be shorten to zero with reasonable initial *** this basis,we experimentally generate a distributed CTS with a calculation interval of 500 s and its stability outperforms those of the member clocks when the averaging time is longer than1700 *** experimental result proves that the CTS’s real-time performance is significantly improved.

关键词： composite time scale real-time performance calculation interval adjustment stage

Opportunities for production and property research of neutron-rich nuclei around N=12. at HIAF

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Nuclear Science and Techniques 2024年第6期35卷 101-113页

作者： Shao-Bo Ma Li-Na Sheng Xue-Heng Zhang Shi-Tao wang Kai-Long wang Chun-wang Ma Hool-Jin Ong Zhi-Yu Sun Shu-Wen Tang Yu-Hong Yu Xin-Tong Du Xiao-Bao Wei Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516000China university of Chinese Academy of Sciences Beijing 100049China College of Physics Henan Normal UniversityXinxiang 453007China Institute of Nuclear Science and Technology Henan Academy of ScienceZhengzhou 450046China Joint-department for Nuclear Physics Lanzhou University and Institute of Modern PhysicsLanzhou 730000China Research Center for Nuclear Physics Osaka UniversityOsaka 567-0047Japan RIKEN Nishina Center Saitama 351-0198Japan Northwest Normal university Lanzhou 730070China

The study of nuclide production and its properties in the N=12. neutron-rich region is prevalent in nuclear physics and astrophysics *** upcoming High-energy FRagment Separator(HFRS)at the High-Intensity heavy-ion Accelerator Facility(HIAF),an in-flight separator at relativistic energies,is characterized by high beam intensity,large ion-optical acceptance,high magnetic rigidity,and high momentum resolution *** provides an opportunity to study the production and properties of neutron-rich nuclei around N=*** this paper,an experimental scheme is proposed to produce neutron-rich nuclei around N=12. and simultaneously measure their mass and lifetime based on the HFRS separator;the feasibility of this scheme is evaluated through *** results show that under the high-resolution optical mode,many new neutron-rich nuclei approaching the r-process abundance peak around A=195 can be produced for the first time,and many nuclei with unknown masses and lifetimes can be produced with high *** the time-of-flight corrected by the measured dispersive position and energy loss information,the cocktails produced from 2.8 Pb fragmentation can be unambiguously ***,the masses of some neutron-rich nuclei near N=12. can be measured with high precision using the time-of-flight magnetic rigidity *** indicates that the HIAF-HFRS facility has the potential for the production and property research of neutron-rich nuclei around N=12.,which is of great significance for expanding the chart of nuclides,developing nuclear theories,and understanding the origin of heavy elements in the universe.

关键词： HFRS Fragmentation Neutron-rich nuclei around N=12. Mass measurement Lifetime