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Health diagnosis of ultrahigh arch dam performance using heterogeneous spatial panel vector model

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Water Science and Engineering 2024年第2期17卷 177-186页

作者： Er-feng Zhao xin Li Chong-shi gu The National Key Laboratory of Water Disaster Prevention Hohai UniversityNanjing 210098China NationalEngineering Research Centerof Water Resources Eficient Utilization and Engineering Safety Hohai UniversityNanjing 20098China

Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in *** control is essential to long-term operation of these *** study employed the flexibility coefficient and plastic complementary energy norm to assess the structural safety of arch dams.A comprehensive analysis was conducted,focusing on differences among conventional methods in characterizing the structural behavior of the Xiaowan arch dam in ***,the spatiotemporal characteristics of the measured performance of the Xiaowan dam were explored,including periodicity,convergence,and time-effect *** findings revealed the governing mechanism of main ***,a heterogeneous spatial panel vector model was developed,considering both common factors and specific factors affecting the safety and performance of arch *** model aims to comprehensively illustrate spatial heterogeneity between the entire structure and local regions,introducing a specific effect quantity to characterize local deformation ***,the proposed model was applied to the Xiaowan arch dam,accurately quantifying the spatiotemporal heterogeneity of dam ***,the spatiotemporal distri-bution characteristics of environmental load effects on different parts of the dam were reasonably *** of the model prediction enhances its credibility,leading to the formulation of health diagnosis criteria for future long-term operation of the Xiaowan *** findings not only enhance the predictive ability and timely control of ultrahigh arch dams'performance but also provide a crucial basis for assessing the effectiveness of engineering treatment measures.

关键词： Ultrahigh arch dam Structural performance Deformation behavior Diagnosis criterion Panel data model

Efficient stochastic analysis of unsaturated slopes subjected to various rainfall intensities and patterns

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Geoscience Frontiers 2023年第1期14卷 346-359页

作者： xin gu Lin Wang Qiang Ou Wengang Zhang School of Civil Engineering Chongqing UniversityChongqing 400045China

Rainfall infiltration poses a disastrous threat to the slope stability in many regions around the *** paper proposes an extreme gradient boosting(XGBoost)-based stochastic analysis framework to estimate the rainfall-induced slope failure *** unsaturated slope under rainfall infiltration in spatially varying soils is selected in this study to investigate the influences of the spatial variability of soil properties(including effective cohesion c',effective friction angleφ'and saturated hydraulic conductivity k_(s)),as well as rainfall intensity and rainfall pattern on the slope failure *** show that the proposed framework in this study is capable of computing the failure probability with accuracy and high *** spatial variability of k_(s)cannot be overlooked in the reliability ***,the rainfall-induced slope failure probability will be *** is found that the rain-fall intensity and rainfall pattern have significant effect on the probability of ***,the failure probabilities under various rainfall intensities and patterns can be easily obtained with the aid of the proposed framework,which can provide timely guidance for the landslide emergency management departments.

关键词： Slope stability Rainfall infiltration Stochastic analysis Sspatial variability

Theoretical investigation of tunable polarized broadband terahertz radiation from magnetized gas plasma

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Chinese Physics B 2018年第5期27卷 539-544页

作者： xin-Yang gu Jin-Song Liu Zhen-Gang Yang sheng-Lie Wang Ke-Jia Wang Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China

The mechanism of terahertz(THz)pulse generation with a static magnetic field imposed on a gas plasma is theoretically *** investigation demonstrates that the static magnetic field alters the electron motion during the optical field ionization of gas,leading to a two-dimensional asymmetric acceleration process of the ionized *** results reveal that elliptically or circularly polarized broadband THz radiation can be generated with an external static magnetic field imposed along the propagation direction of the two-color *** polarization of the THz radiation can be tuned by the strength of the external static magnetic field.

关键词： terahertz plasma magnetic field polarization

A novel Zn-PANI dry rechargeable battery

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Rare Metals 2006年第Z1期25卷 67-70页

作者： WANG xinsheng JIN xin gu Dawei SHEN Linjiang College of Science Nanjing University of Technology Nanjing 210009 China College of Science Nanjing University of Technology Nanjing 210009 China College of Science Nanjing University of Technology Nanjing 210009 China College of Science Nanjing University of Technology Nanjing 210009 China

Conducting polyaniline (PANI) powder was well mixed with graphite and acetylene black to obtain the optimum conductivity and porosity. The mixed powder was compressed into a pellet for cathode. Zinc powder was mixed with some metal powder, and compressed into a pellet used as the anode. The electrolyte comprised ZnCl2, NH4Cl, Triton-X100 and PVA at pH 3. The battery has an open-circuit voltage of 1.44 V. The battery underwent charge-discharge cycle with a constant current density of 3 mA·cm-2, within the voltage range of 0.40-1.68 V. It is found that the capacity of the battery is related to the charge-discharge cycles, the maximum capacity is 67.9 mAh·g-1, and Coulombic efficiency is between 95% and 100%. The battery stability was also investigated after 78 d of standing without use. It is found that the battery experiences a self-discharge of less than 0.29% per day.

关键词： polyaniline rechargeable battery capacity charge-discharge cycle

Stellar ages and metallicities of nearby elliptical galaxies

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Research in Astronomy and Astrophysics 2009年第11期9卷 1215-1229页

作者： Bai-Tian Tang Qiu-sheng gu Song Huang Department of Astronomy Nanjing University Nanjing 210093 China

Stellar ages and metallicities are crucial for understanding the formation and evolution of elliptical galaxies. However, due to the age-metallicity degeneracy, it is hard to measure these two parameters accurately with broad-band photometry. In this paper, we observed high-resolution spectra for a sample of 20 nearby elliptical galaxies （EGs） with the NAOC 2.16 m telescope, and determined stellar ages and metallicities by using the empirical population synthesis and Lick/IDS index system methods. We found that stellar ages from these two methods are consistent with each other for purely old EGs; however, stellar metallicities show a zeropoint offset of 0.5 Z⊙. Our results confirm that stellar populations in low-density environment galaxies are more diverse compared to their high-density counterparts. We also investigated the element abundance-galaxy mass relation for nearby elliptical galaxies.

关键词： galaxies elliptical and lenticular, cD -- galaxies statistics -- galaxies stellar content

Surface photometry and radial color gradients of nearby luminous early-type galaxies in SDSS Stripe 82

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Research in Astronomy and Astrophysics 2011年第3期11卷 309-326页

作者： Fang-Zhou Jiang Song Huang Qiu-sheng gu Department for Intensive Instruction Kuang Yaming Honors School Nanjing University Nanjing 210093 China Department of Astronomy Nanjing University Nanjing 210093 China

We make use of the images from the Sloan Digital Sky Survey Stripe 82（Stripe 82） to present an analysis of r band surface brightness profiles and radial color gradients（g-r,u-r） in our sample of 111 nearby early-type galaxies（ETGs） .Thanks to the Stripe 82 images,each of which is co-added from about 50 single frames,we are able to pay special attention to the low-surface-brightness areas（LSB areas） of the *** LSB areas affect the Sérsic fittings and concentration indices by making both of the indices less than the typical values for *** the Sérsic fits to all the surface brightness profiles,we found some Sérsic indices that range from 1.5 to 2.5,much smaller than those of typical de Vaucouleur profiles and relatively close to those of exponential disks,and some others much larger than four but still with accurate *** galaxies cannot be fitted with a single Sérsic profile,but once we try double Sérsic profiles,the fittings are improved：one with a profile relatively close to the de Vaucouleur law in the inner area and a profile relatively close to an exponential law in the LSB area,the other with a nice fitting in the inner area but still having a failed fitting in the outer *** 60%of the sample has negative color gradients（red-core） within 1.5Re,much more than the approximately 10%positive ones（blue-core） within the same ***,taking into account the LSB areas,we find that the color gradients are not necessarily monotonic：about one third of the red-core（or blue-core） galaxies have positive（or negative） color gradients in the outer areas. So LSB areas not only make ETGs’Sérsic profiles deviate from de Vaucouleur ones and shift to the disk end,but also reveal that quite a number of ETGs have opposite color gradients in inner and outer *** outcomes remind us of the necessity of double-Sérsic *** LSB phenomena may be interpreted by mergers and thus have different metallicity in the outer *** parameters ar

关键词： galaxies:early-type galaxies—galaxies:surface brightness profiles and color gradients—techniques:photometric

Conditional privacy protection authentication scheme based on bilinear pairings for VANET

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The Journal of China Universities of Posts and Telecommunications 2020年第1期27卷 62-71页

作者： Song Cheng gu xin'an Ping Yuan Zhang Yadong School of Computer Science and Technology Henan Polytechnic UniversityJiaozuo 454000China School of Information Engineering Xuchang UniversityXuchang 461000China

To solve the problem of security and efficiency of anonymous authentication in the vehicle Ad-hoc network(VANET), a conditional privacy protection authentication scheme for vehicular networks is proposed based on bilinear pairings. In this scheme, the tamper-proof device in the roadside unit(RSU) is used to complete the message signature and authentication process together with the vehicle, which makes it more secure to communicate between RSU and trusted authority(TA) and faster to update system parameters and revoke the vehicle. And this is also cheaper than installing tamper-proof devices in each vehicle unit. Moreover, the scheme provide provable security proof under random oracle model(ROM), which shows that the proposed scheme can meet the security requirements such as conditional privacy, unforgeability, traceability, etc. And the results of simulation experiment demonstrate that this scheme not only of achieves high efficiency, but also has low message loss rate.

关键词： VANET anonymous authentication bilinear pairings conditional privacy protection

Modified Bishop method for stability analysis of weakly sloped subgrade under centrifuge model test

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Frontiers of Structural and Civil Engineering 2021年第3期15卷 727-741页

作者： Ke sheng Bao-Ning HONG xin LIU Hao SHAN Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China Jiangsu Research Center for Geotechnical Engineering Technology Hohai UniversityNanjing210098China Geotechnical Research Institute Hohai UniversityNanjing210098China Research Institute of Tunnel and Underground Engineering Hohai UniversityNanjing 210098China School of Civil Engineering Xuzhou University of TechnologyXuzhou 221018China

The sliding forms of weak sloped and horizontal subgrades during the sliding process *** addition,the sliding form of weakly sloped subgrades exhibits considerable slippage and *** accuracy of traditional slice methods for computing the stability safety factor of weakly sloped subgrades is insufficient for a subgrade *** this study,a novel modified Bishop method was developed to improve the accuracy of the stability safety factor for different inclination *** instability mechanism of the weakly sloped subgrade was considered in the proposed method using the“influential force”and“additional force”***“additional force”reflected the weight effect of the embankment fill,whereas the“influential force”reflected the effect of the potential energy *** simulations and experimental tests were conducted to evaluate the advantages of the proposed modified Bishop *** with the traditional slice method,the error between the proposed method and the exact value is less than 32.3%in calculating the safety factor.

关键词： weakly sloped subgrade stability analysis additional force influential force modified Bishop method

Scatter Search Based Particle Swarm Optimization Algorithm for Earliness/Tardiness Flowshop Scheduling with Uncertainty

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International Journal of Automation and computing 2016年第3期13卷 285-295页

作者： Jia-Can Geng Zhe Cui xing-sheng gu Key Laboratory of Advanced Control and Optimization for Chemical Process Ministry of EducationEast China University of Science and Technology

Considering the imprecise nature of the data in real-world problems, the earliness/tardiness （E/T） fiowshop scheduling problem with uncertain processing time and distinct due windows is concerned in this paper. A fuzzy scheduling model is established and then transformed into a deterministic one by employing the method of maximizing the membership function of middle value. Moreover, an effective scatter search based particle swarm optimization （SSPSO） algorithm is proposed to minimize the sum of total earliness and tardiness penalties. The proposed SSPSO algorithm incorporates the scatter search （SS） algorithm into the frame of particle swarm optimization （PSO） algorithm and gives full play to their characteristics of fast convergence and high diversity. Besides, a differential evolution （DE） scheme is used to generate solutions in the SS. In addition, the dynamic update strategy and critical conditions are adopted to improve the performance of SSPSO. The simulation results indicate the superiority of SSPSO in terms of effectiveness and efficiency.

关键词： Earliness/tardiness (E/T) scheduling fuzzy modeling scatter search (SS) particle swarm optimization (PSO).