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A New Method for Identifying the Model Error of Adjust ment System

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Geo-Spatial Information Science 2005年第3期8卷 189-192页

作者： TAO Benzao zhang chaoyu School of Geodesy ＆ Geomatics Wuhan University 129 Luoyu Road Wuhan 430079 China. 不详

Some theory problems affecting parameter estimation are discussed in this paper. Influence and transformation between errors of stochastic and functional models is pointed out as well. For choosing the best adjustment model, a formula, which is different from the literatures existing methods, for estimating and identifying the model error, is proposed. On the basis of the proposed formula, an effective approach of selecting the best model of adjustment system is given.

关键词： adjustment model model error model error estimation model error identification

Tensile properties analysis of CFRP-titanium plate multi-bolt hybrid joints

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Chinese Journal of Aeronautics 2022年第3期35卷 464-474页

作者： Yanping ZHENG chaoyu zhang Ying TIE Xu WANG Mingkun LI School of Mechanical and Power Engineering Zhengzhou UniversityZhengzhou 450001China

Hybrid joints have better tensile properties than pure bonded and bolted bolts,and are increasingly used in the aerospace *** tests are carried out for the Hybrid Bonded/Bolted(HBB)joints of Carbon Fiber Reinforced Polymer(CFRP)laminate and titanium alloy plate under different bolt numbers,and the corresponding load–displacement curves are *** the same time,based on Continuum Damage Mechanics(CDM)theory,which is derived from 3D Hashin failure criteria,and a Cohesive Zone Model(CZM),the tensile strength prediction model of the composite laminate-titanium alloy plate multi-bolted HBB joint was established,and the numerical simulation results were in good agreement with the experimental height,which validate the feasibility of the *** difference in the bearing capacity of HBB joints under different numbers of bolts is compared and *** this basis,the influence of inter-bolt distance on the tensile properties of the HBB joints is *** results show that the double-nail HBB joints can effectively improve the end warpage and low bearing capacity of the single-nail HBB *** tensile failure load of the double-nail HBB joints under the standard lap width(30 mm)is 82.6%higher than that of the single nail,the tensile failure load of the three-bolt HBB joints is 34.1%higher than that of the double *** the three-bolt HBB joint,the joint strength is controlled by the adhesive and the external bolt,while the internal bolt is redundant,the hybrid joint can be simplified by reducing the middle *** inter-bolt distance has a great influence on the failure load of the hybrid *** the inter-bolt distance can effectively improve the bearing capacity of the structure.

关键词： CFRP laminate Finite element model Hybrid(bonded/bolted)joint Multi-bolt Tensile properties

Distribution of Intra-Crustal Low Velocity Zones beneath Yunnan from Seismic Ambient Noise Tomography

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Journal of Earth Science 2018年第6期29卷 1409-1418页

作者： Weibing Qin Shuangxi zhang Mengkui Li Tengfei Wu chaoyu zhang Department of Geophysics School of Geodesy and GeomaticsWuhan Universi.tvWuhan 430079China China Three Gorges Corporation Yiehang 443000China Key Laboratory of Geospace Environment and Geodesy of Ministry of Education Wuhan UniversityWuhan 430079China Collaborative Innovation Center of Geospace Information Science Wuhan UniversityWuhan 430079China

Previous studies have reached consensus that low velocity zones are widespread in the crust beneath Yunnan region. However, the relationships between the low velocity zones and large faults, earthquake distribution are less investigated by available studies. By analyzing the seismic ambient noise recorded by Yunnan Seismic Networks and Tengchong volcano array, we construct a 3D crustal shear wave velocity model for the Yunnan region, which provides more details of the distribution of intra-crustal low velocity zones all over Yunnan. The distribution of low velocity zones shows different features at different depths. At shallow depths, the results are well correlated with near surface geological features. With increasing depth, the low velocity zones are gradually concentrated on the northern part of our study area, most likely reflecting variations in crustal thickness beneath the Yunnan region. The low velocity zones are truncated at depth by several large faults in Yunnan. It is interesting that most strong earthquakes（Ms≥5.0） occurred in Yunnan are distributed in low velocity zones or the transition zones between low and high velocity anomalies within the upper-to-middle crust. The crustal structure is composed of a brittle, seismically active upper-to-middle crust and a warm, aseismic lower crust.

关键词： ambient noise tomography crustal structure low velocity zone fault strong earthquake

Recovering Period of Postseismic Fluid Pressure in Fault Valve

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Journal of Earth Science 2015年第4期26卷 530-536页

作者： Shuangxi zhang Chen zhang Yu zhang chaoyu zhang Lingxi Liu Mengkui Li School of Geodesy and Geomatics Wuhan University Key Laboratory of Environment and Geodesy Ministry of EducationWuhan

The present study aims to reveal the recovering period of the postseismic fluid pressure in fault zone, offering an insight into earthquake recurrence. Numerical modeling is performed based on a 2D simple layered fault-valve model to simulate the fluid activities within the earthquake fault. In order to demonstrate the features of postseismic fluid pressure in natural state, the interference of tectonic movements is not considered. The recovering period of postseismic fluid pressure includes a sudden- changing period and a much longer fluctuating period. Modeling results show that fault permeability and porosity are sensitive parameters and reversely proportional to the recovering period of the fluid pressure in earthquake fault zone. When the permeability reduces from 10^-15 to 10^-18 m^2, the recovering period increases from 400 to 2 000 yrs, correspondently. The upper and lower fluid pressures are sepa- rated by the valve seal, causing their fluctuations in opposite tendencies.

关键词： recovering period fluid pressure fault valve numerical modeling thermal anomaly.

Resourceful Utilization of Tannery Wastewater

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Chinese Journal of Population,Resources and Environment 2012年第1期10卷 116-121页

作者： Wang Chen Wang Xikui Ding Maochen zhang chaoyu College of Light Chemical and Environmental Engineering Shandong Polytechnic University Jinan Shandong 250353 China

Leather industry is an important light industry in *** making requires a series of chemical ***,unhairing and chrome tanning wastewaters are the main portions of tannery *** and reusing these wastewaters can eliminate 80% of COD,75% of BOD,95% of chromium and 93% of sulfuret,furthermore reduce environment impact,decrease treatment costs,save chemicals and *** application methods of wastewater reclamation and reuse for different operations were *** suitable reclamation and reuse technologies can enable leather making processes more rational,and realize the recovery and recycle of several chemicals in the *** utilization of tannery wastewater should mate with renovating production technology,updating equipment,and must be guaranteed sufficiently by environmental protection measures.

关键词： leather industry wastewater waste liquor treatment resourceful utilization

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平差系统的模型误差及其识别方法研究

武汉大学学报（信息科学版） 2005年第10期30卷 897-899,904页

作者：张朝玉陶本藻武汉大学测绘学院

论述了模型误差影响参数估值的一些理论问题,指出了随机模型误差和函数模型误差之间的相互作用和转化。为讨论平差系统最优模型的选取,给出了与现有文献将模型误差纳入平差系统的思路不同的一个估计和识别模型误差的理论基础公式,由此... 详细信息

论述了模型误差影响参数估值的一些理论问题,指出了随机模型误差和函数模型误差之间的相互作用和转化。为讨论平差系统最优模型的选取,给出了与现有文献将模型误差纳入平差系统的思路不同的一个估计和识别模型误差的理论基础公式,由此导出了相应的实用公式,给出了平差系统模型的优选方法。

关键词：平差模型模型误差模型误差估计模型误差识别

以机关报活动为核心:日本共产党的特色党建制度考察

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社会主义研究 2024年第5期 129-137页

作者：张朝钰中国人民大学马克思主义学院

日本共产党的党势何以崛起何以颓靡并不单单是一个意识形态领域的问题,在更大程度上,这应是一个党建领域的问题。以机关报为核心的党活动作为日共党建领域的特色创建,在政治建设、财政建设、组织建设上都发挥了至关重要的作用,是日共在... 详细信息

日本共产党的党势何以崛起何以颓靡并不单单是一个意识形态领域的问题,在更大程度上,这应是一个党建领域的问题。以机关报为核心的党活动作为日共党建领域的特色创建,在政治建设、财政建设、组织建设上都发挥了至关重要的作用,是日共在发达资本主义国家这个特殊的国情下进行马克思主义本土化探索的理论结晶,也是理解和把握战后日共发展脉络的主线。

关键词：日本共产党《赤旗》党的建设

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基于双电阻辨识方法的感应电机暂态温度计算

中国电机工程学报 2018年第6期38卷 1865-1872页

作者：张超羽王立国哈尔滨工业大学电气工程及自动化学院

感应电机的状态监测是其稳定可靠运行的关键,电机的运行温度是其一项重要的指标。为了评估感应电机的运行温度,提出一种基于双电阻辨识方法的感应电机暂态温度计算方法。首先,利用基于转子磁链的模型参考自适应对当前时刻电阻阻值进行... 详细信息

感应电机的状态监测是其稳定可靠运行的关键,电机的运行温度是其一项重要的指标。为了评估感应电机的运行温度,提出一种基于双电阻辨识方法的感应电机暂态温度计算方法。首先,利用基于转子磁链的模型参考自适应对当前时刻电阻阻值进行修正。进而基于上述参数可以得到电机损耗,用于计算感应电机暂态温度。在此基础上,根据金属电阻与温度的近似线性关系,得到未修正的暂态电阻阻值。重复上述计算,可以实现对电机定转子侧温度的观测,理论分析与实验结果验证了所提方法的可行性与有效性。

关键词：暂态温度感应电机参数辨识电机损耗

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城市地噪声场的多元分离方法

武汉大学学报（信息科学版） 2016年第12期41卷 1690-1695页

作者：秦维秉张双喜李孟奎张煜张晨张朝玉武汉大学测绘学院湖北武汉430079 武汉大学地球空间环境与大地测量教育部重点实验室湖北武汉430079

城市地下噪声场由自然地噪声和人文地噪声组成,人文地噪声和自然地噪声的差异主要表现在时空分布的一致性、稳定性和相关性等方面。针对两者的不同特征,提出了噪声分离的三原则,采用多元分离的方法,实现了两类地噪声的有效分离。通过对... 详细信息

城市地下噪声场由自然地噪声和人文地噪声组成,人文地噪声和自然地噪声的差异主要表现在时空分布的一致性、稳定性和相关性等方面。针对两者的不同特征,提出了噪声分离的三原则,采用多元分离的方法,实现了两类地噪声的有效分离。通过对比测试4种标准信号并进行分析,可得出该方法效果好于传统的小波方法的结论。深圳市地噪声场的探测试验表明,多元分离方法能够把地噪声有效分离成人文地噪声和自然地噪声两部分,它们可以分别提炼出地下地质信息。

关键词：城市地噪声自然地噪声人文地噪声多元分离技术小波分解