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近代胶济铁路筹款赎路运动述论

齐鲁学刊 2010年第3期 53-58页

作者：杜平首都师范大学历史系北京100048

一战爆发后,日本侵占青岛,将胶济铁路纳入直接统治之下长达八年之久。为收回该路,中国在华盛顿会议上同日本进行了艰难的交涉,最终确定了"债券赎路"的方案。为筹集赎路所需的巨额赎金,中国政府先是计划将胶济铁路付诸民办,即由国民筹款... 详细信息

一战爆发后,日本侵占青岛,将胶济铁路纳入直接统治之下长达八年之久。为收回该路,中国在华盛顿会议上同日本进行了艰难的交涉,最终确定了"债券赎路"的方案。为筹集赎路所需的巨额赎金,中国政府先是计划将胶济铁路付诸民办,即由国民筹款赎回该路,收回后归民办,永属民业。政府为此设立筹款机关,并制定了较为缜密的招股、储金简章,社会各界也积极响应,但由于种种原因,胶济铁路民办的尝试最终失败。之后,胶济铁路本身的收入就成了筹集赎路款项的唯一来源。胶济铁路筹款赎路运动并不是偶然的历史现象,它是近代中国具"文明排外"特点的赎路情结的表现。

关键词：胶济铁路赎路民办铁路

Robust Active Suspension Design Subject to Vehicle Inertial Parameter Variations

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International Journal of Automation and computing 2010年第4期7卷 419-427页

作者： Hai-ping du Nong Zhang School of Electrical Computer and Telecommunications Engineering University of Wollongong Wollongong NSW 2522 Australia Mechatronics and Intelligent Systems Faculty of Engineering University of Technology Broadway NSW 2007 Australia

This paper presents an approach in designing a robust controller for vehicle suspensions considering changes in vehicle inertial properties. A four-degree-of-freedom half-car model with active suspension is studied in this paper, and three main performance requirements are considered. Among these requirements, the ride comfort performance is optimized by minimizing the Ho~ norm of the transfer function from the road disturbance to the sprung mass acceleration, while the road holding performance and the suspension deflection limitation are guaranteed by constraining the generalized H2 （GH2） norms of the transfer functions from the road disturbance to the dynamic tyre load and the suspension deflection to be less than their hard limits, respectively. At the same time, the controller saturation problem is considered by constraining its peak response output to be less than a given limit using the GH2 norm as well. By solving the finite number of linear matrix inequalities （LMIs） with the minimization optimization procedure, the controller gains, which are dependent on the time-varying inertial parameters, can be obtained. Numerical simulations on both frequency and bump responses show that the designed parameter-dependent controller can achieve better active suspension performance compared with the passive suspension in spite of the variations of inertial parameters.

关键词： Active suspension half-car suspension model parameter-dependent control linear matrix inequalities (LMIs)

A Galaxy Image Augmentation Method Based on Few-shot Learning and Generative Adversarial Networks

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Research in Astronomy and Astrophysics 2024年第3期24卷 180-193页

作者： Yiqi Yao Jinqu Zhang ping du Shuyu Dong School of Artificial Intelligence South China Normal UniversityFoshan 528225China School of Computer Science South China Normal UniversityGuangzhou 510631China Guangdong Construction Vocational Technology Institute Guangzhou 511500China

Galaxy morphology classifications based on machine learning are a typical technique to handle enormous amounts of astronomical observation data,but the key challenge is how to provide enough training data for the machine learning *** this article proposes an image data augmentation method that combines few-shot learning and generative adversarial *** Galaxy10 DECaLs data set is selected for the experiments with consistency,variance,and augmentation effects being *** popular networks,including AlexNet,VGG,and ResNet,are used as examples to study the effectiveness of different augmentation methods on galaxy morphology *** results show that the proposed method can generate galaxy images and can be used for expanding the classification model’s training *** to comparative studies,the best enhancement effect on model performance is obtained by generating a data set that is 0.5–1 time larger than the original data ***,different augmentation strategies have considerably varied effects on different types of ***-GAN achieved the best classification performance on the ResNet network for In-between Round Smooth Galaxies and Unbarred Loose Spiral Galaxies,with F1 Scores of 89.54%and 63.18%,*** comparison reveals that various data augmentation techniques have varied effects on different categories of galaxy morphology and machine learning ***,the best augmentation strategies for each galaxy category are suggested.

关键词： techniques image processing-galaxies structure-galaxies general

Chlorobenzenes in waterweeds from the Xijiang River (Guangdong section) of the Pearl River

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Journal of Environmental Sciences 2007年第10期19卷 1171-1177页

作者： du Qing-ping JIA Xiao-shan HUANG Cai-na Faculty of Environmental Science and Engineering Guangdong University of Technology Guangzhou 510006 China School of Environmental Science and Engineering Sun Yat-sen University Guangzhou 510275 China

The Xijiang River is the major source of water for about 4.5 millions of urban population and 28.7 millions of rural population. The water quality is very important for the health of the rural population. The concentration and distribution of chlorobenzenes （CBs） in both water and waterweeds collected from 4 stations in the Xijiang River （Gangdong section） of the Pearl River in April and November were determined. The result showed that nearly every congener of CBs was detected. The total contents of CBs （ZCBs） in the river water ranged from 111.1 to 360.0 ng/L in April and from 151.9 to 481.7 ng/L in November, respectively. The pollution level of CBs in the water in April was higher than that in November. The contents of ZCBs in waterweeds ranged from 13.53×10^2μg/g to 38.27×10^2μg/g dry weight （dw）. There was no significant difference between April and November in waterweeds. The distribution of CBs in roots, caulis, and leaves of Vallisneria spiralis L. showed different patterns. The leaves mainly contained low-molecular-weight CBs （DCBs）, whereas the roots accumulated more PCBs and HCBs. The average lgBCFlip （bioconcentration factor） of CBs ranged from 0.64 to 3.57 in the waterweeds. The spatial distribution character of CBs in the Xijiang River was： Fengkai County 〈 Yunan County 〈 Yun＇an County 〈 Gaoyao County according to the ZCBs, and the pollution deteriorated from the upstream to the downstream of the Xijiang River. Further analysis demonstrated that the discharge of waste containing CBs may be the main source of CBs pollution in the Xijiang River .

关键词： chlorobenzenes pollution water water weeds distribution bioconcentration factor

A survey of baroclinic tides in the Beibu Gulf in the South China Sea

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Acta Oceanologica Sinica 2007年第4期26卷 7-19页

作者： CHEN Ju WANG Dongxiao SHI ping du Yan Key Laboratory of Tropical Marine and Environmental Dynamics South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

The principal characteristics of the tides are investigated by a shipborne acoustic Doppler current Profiler at a fixed station located in the Beibu Gulf from 4 to 14 April 2003. Data analysis indicates that the diurnal tidal currents dominate local current variations at the observing site. Except the barotropic ME constituent, four principal tides comprise both back-and-forth barotropic and baroclinic tidal currents. The baroclinic tidal ellipse parameters vary with depth, showing complicate features, rather than monotonous features being figured. For baroclinic tidal constituents, vertical modes are different to each other. Similarly, the semi-major axes of the tidal constituents vary with depth. In the lower layer, a nonlinear regression approach is used to calculate and obtain the SEMA profiles of diurnal tidal constituents. Results show that in the thin bottom boundary layer, all of the parameters vary drastically with depth, totally distinguished from the vertical profiles above.

关键词： vertical structure baroclinic tidal current Beibu Gulf

Analytical general results for handoff dwell time distribution in wireless networks

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The Journal of China Universities of Posts and Telecommunications 2006年第4期13卷 29-33页

作者： ZHANG Zu-fan du Hui-ping JIANG Ze University of Posts and Telecommunications Chongqing 400065 China University of Electronic Science and Technology of China Chengdu 610065 China

This article presents a general evaluation of handoff dwell time distribution based on geometric analysis methods. Considering the geometric characteristic of the deployed sector pattern, and the distribution of the users＇ position and the moving direction in the given sector, the general formulas of the probability density function of sector handoff dwell time are derived. Some numerical results are also presented for illustration.

关键词： wireless networks handoff dwell time probability density function

The Logic of Contingency in China＇s Insistence on the Non-interference Principle

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Fudan Journal of the Humanities and Social Sciences 2015年第4期8卷 597-615页

作者： Zhongqi Pan ping du School of International Relations and Public Affairs Fudan University 220 Handan RoadShanghai 200433 China School of Chinese Language and Literature Linyi University Middle Shuangling RoadLinyi 276000 Shandong China

China＇s insistence on the non-interference principle has been increasingly inconsistent. While China＇s concern with sovereignty, regime security, and legitimacy, as well as its developing country identity, have pushed it to continue its insistence on the principle of non-interference, China＇s further adaptation to the international system, increasing engagement in intemational institutions, and new identity as a responsible power have led China to drag its feet on the same principle. To reconcile these competing forces, China has to make concessions, namely, setting preconditions to legitimize intervention, designing a sovereignty-first solution, and/or complementing the non-interference principle with alternative principles. China＇s application of the non-interference principle has thus been made contingent. It is more inflexible at one end of a spectrum and more flexible at the other end, with China＇s foreign policies shifting back and forth between them.

关键词： China · Non-interference · Principle · Intervention · Sovereignty · Insistence

Galaxy Morphology Classification Using a Semi-supervised Learning Algorithm Based on Dynamic Threshold

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Research in Astronomy and Astrophysics 2023年第11期23卷 169-182页

作者： Jie Jiang Jinqu Zhang Xiangru Li Hui Li ping du School of Computer Science South China Normal UniversityGuangzhou 510631China Guangdong Construction Vocational Technology Institute Qingyuan 511500China

Machine learning has become a crucial technique for classifying the morphology of galaxies as a result of the meteoric development of galactic ***,traditional supervised learning has significant learning costs since it needs a lot of labeled data to be ***,a semi-supervised learning algorithm that serves as a good method,is now a key tool for using large amounts of unlabeled ***,the performance degrades significantly when dealing with large,imbalanced data sets since FixMatch relies on a fixed threshold to filter ***,this study proposes a dynamic threshold alignment algorithm based on the FixMatch ***,the class with the highest amount has its reliable pseudo-label ratio determined,and the remaining classes'reliable pseudo-label ratios are approximated in ***,based on the predicted reliable pseudo-label ratio for each category,it dynamically calculates the threshold for choosing *** employing this dynamic threshold,the accuracy bias of each category is decreased and the learning of classes with less samples is *** results show that in galaxy morphology classification tasks,compared with supervised learning,the proposed algorithm significantly improves *** the amount of labeled data is 100,the accuracy and F1-score are improved by 12.8%and 12.6%,*** with popular semisupervised algorithms such as FixMatch and MixMatch,the proposed algorithm has better classification performance,greatly reducing the accuracy bias of each *** the amount of labeled data is 1000,the accuracy of cigar-shaped smooth galaxies with the smallest sample is improved by 37.94%compared to FixMatch.

关键词： galaxies:photometry techniques:image processing techniques:photometric

Phosphate-induced differences in stabilization efficiency for soils contaminated with lead, zinc, and cadmium

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Frontiers of Environmental Science & Engineering 2018年第2期12卷 97-105页

作者： Jie Ren Zhuo Zhang Mei Wang Guanlin Guo ping du Fasheng Li College of Water Sciences Belling Normal Unive~ity Beijing 100875 China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Beijing 100012 China

Phosphates can cost-effectively decrease the mobility of Pb in contaminated soils. However, Pb always coexists with other metals in soil, their competitive reactions with phosphates have not been tested. In this study, the abilities of KHzPO4, K2HPO4, and K3PO4 to stabilize Pb, Zn, and Cd in soils contaminated with a single metal or a ternary metal for different phosphorus/metal molar ratios were investigated. Results indicated that the stabilization efficiency of KH2PO4, K2HPO4, and K3PO4 for Pb, Zn, and Cd in single metal contaminated soil （P/M ratio 0.6） was 96.00%-98.74%, 33.76%-47.81%, and 9.50%-55.79%, respectively. Competitive stabilization occurred in the ternary system, Pb exhibited a strong competition, the stabilization efficiency of Zn and Cd reduced by 23.50%- 31.64%, and 7.10%--39.26%, respectively. Pyromorphite and amorphous lead phosphate formed with excess KH2PO4 or K2HPO4 addition, while K3PO4 resulted in the formation of a hydroxypyr- omorphite precipitate. Amorphous Zn and Cd phosphates and hydroxides were the primary products. The immobilization rate of Zn and Cd depends on pH, and increased significantly in response to the excess phosphate application. This approach provides insight into phosphate-induced differences in stabilization efficiency in soils contaminated with multiple metals, which is of theoretical and engineering significance.

关键词： Heavy metals Metal-contaminated soil Phosphate Competitive stabilization