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Response Sensitivity Analysis of the Dynamic Milling Process Based on the Numerical Integration Method

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Chinese Journal of Mechanical Engineering 2012年第5期25卷 940-946页

作者： ding Ye ZHU Limin ZHANG Xiaojian ding Han State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University Shanghai 200240 China State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology Wuhan 430074 China

As one of the bases of gradient-based optimization algorithms, sensitivity analysis is usually required to calculate the derivatives of the system response with respect to the machining parameters. The most widely used approaches for sensitivity analysis are based on time-consuming numerical methods, such as finite difference methods. This paper presents a semi-analytical method for calculation of the sensitivity of the stability boundary in milling. After transforming the delay-differential equation with time-periodic coefficients governing the dynamic milling process into the integral form, the Floquet transition matrix is constructed by using the numerical integration method. Then, the analytical expressions of derivatives of the Floquet transition matrix with respect to the machining parameters are obtained. Thereafter, the classical analytical expression of the sensitivity of matrix eigenvalues is employed to calculate the sensitivity of the stability lobe diagram. The two-degree-of-freedom milling example illustrates the accuracy and efficiency of the proposed method. Compared with the existing methods, the unique merit of the proposed method is that it can be used for analytically computing the sensitivity of the stability boundary in milling, without employing any finite difference methods. Therefore, the high accuracy and high efficiency are both achieved. The proposed method can serve as an effective tool for machining parameter optimization and uncertainty analysis in high-speed milling.

关键词： milling stability sensitivity of the stability boundary numerical integration method

Hierarchical Optimization of Landing Performance for Lander with Adaptive Landing Gear

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Chinese Journal of Mechanical Engineering 2019年第2期32卷 24-35页

作者： Zongmao ding Hongyu Wu Chunjie Wang Jianzhong ding School of Mechanical Engineering and Automation Beijing University of Aeronautics and Astronautics Beijing System Design Institute of Electro-Mechanic Engineering China Aerospace Science and Industry Corporation Limited Department of Mechanical Engineering Tsinghua University State Key Laboratory of Virtual Reality and Systems Beijing University of Aeronautics and Astronautics

A parameterized dynamics analysis model of legged lander with adaptive landing gear was established. Based on the analysis model, the landing performances under various landing conditions were analyzed by the optimized Latin hypercube experimental design method. In order to improve the landing performances, a hierarchical optimization method was proposed considering the uncertainty of landing conditions. The optimization problem was divided into a higher level(hereafter the "leader") and several lower levels(hereafter the "follower"). The followers took condition?ing factors as design variables to find out the worst landing conditions, while the leader took bu er parameters as design variables to better the landing performance under worst conditions. First of all, sensitivity analysis of landing conditioning factors was carried out according to the results of experimental design. After the sensitive factors were screened out, the response surface models were established to reflect the complicated relationships between sensi?tive conditioning factors, bu er parameters and landing performance indexes. Finally, the response surface model was used for hierarchical optimization iteration to improve the computational e ciency. After selecting the optimum bu er parameters from the solution set, the dynamic model with the optimum parameters was simulated again under the same landing conditions as the simulation before. After optimization, nozzle performance against damage is improved by 5.24%, the acceleration overload is reduced by 5.74%, and the primary strut improves its performance by 21.10%.

关键词： Landing gear Soft landing Sensitivity analysis Response surfaces Hierarchical optimization

MC-ICP-MS 测定岩石标准物质的钒同位素组成

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岩矿测试 2025年第1期44卷 63-74页

作者：徐丽怡于慧敏丁昕黄方中国科学技术大学地球和空间科学学院岩石圈演化与环境演变全国重点实验室安徽合肥230026 中国科学院比较行星学卓越创新中心中国科学技术大学安徽合肥230026

随着分析方法的发展和分析精度的提升,钒同位素已经越来越多地被用于各种地质过程研究。为了确保钒同位素分析测试过程中,可以有效地监控数据的准确度和精度,方便国际各实验室之间的数据对比,同时考虑到早期国际上常用美国地质调查局(US... 详细信息

随着分析方法的发展和分析精度的提升,钒同位素已经越来越多地被用于各种地质过程研究。为了确保钒同位素分析测试过程中,可以有效地监控数据的准确度和精度,方便国际各实验室之间的数据对比,同时考虑到早期国际上常用美国地质调查局(USGS)的标准物质面临着库存不足等问题,本文采用多接收电感耦合等离子体质谱仪(MC-ICP-MS)测定了一系列国际地质标准物质和国家地质标准物质的钒同位素组成,δ51V值的测试精度优于0.08‰。本文选取的标准物质主要来自日本地质调查局(GSJ)和中国地质科学院地球物理地球化学勘查研究所(IGGE),包括一个安山岩(JA-1),三个玄武岩(JB-3、JB-1b和GBW07105),一个辉长岩(JGb-1),一个辉绿岩(GBW07123)以及一个土壤(GBW07454),钒含量范围为77~635μg/g,涵盖了目前大部分火成岩和部分土壤等天然样品含量的范围。这些标准物质除了土壤GBW07454,其他标准物质的钒同位素组成未曾被报道。经测量表明,辉长岩标准物质JGb-1具有最高δ51V值,为−1.05‰±0.08‰,安山岩标准物质JA-1具有最低δ51V值,为−0.34‰±0.06‰,其余标准物质的δ51V值变化范围为−0.72‰~−0.81‰,均落在MORB范围内。本文对这些标准物质钒同位素组成的报道,丰富了钒同位素研究的标准物质数据库,有助于未来在更多领域开展钒同位素研究。

关键词：钒同位素火成岩 MC-ICP-MS 标准物质高精度分析方法

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Effects of effluent organic matters on endocrine disrupting chemical removal by ultrafiltration and ozonation in synthetic secondary effluent

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Journal of Environmental Sciences 2019年第2期31卷 57-64页

作者： Xiurong Si Zunfang Hu ding ding Xu Fu Civil Engineering Department North China Institute of Aerospace Engineering Shandong Institute of Geophysical and Geochemical Exploration

Endocrine disrupting chemicals(EDCs) in the secondary effluent discharged from wastewater treatment plants are of great concern when water reuse is intended. Ozonation and ultrafiltration(UF) are powerful technologies reported to eliminate EDCs. Due to the importance of effluent organic matters(EfOMs) in secondary effluent, the effects of three kinds of EfOM on the treatment of five EDCs using ozonation and UF were investigated. The three kinds of EfOM studied were humic acid sodium salt(NaAH), bovine serum albumin(BSA)and sodium alginate(NaAg); and the five EDCs were estrone, 17β-estradiol, estriol, 17α-ethynyl estradiol and bisphenol A. The results showed that EfOM accelerated the decay rate of ozone and inhibited the degradation efficiency of EDCs by ozonation in the order NaAH > BSA > *** ultraviolet absorbance at 280 nm(UVA_(280)) has potential for use as a surrogate indicator to assess EDC removal via ozonation without conducting difficult EDC analyses. When the decline in UVA_(280) exceeded 18%, the five EDCs had been completely removed. The UF behavior of NaAH,BSA and NaAg was found to follow the cake filtration law. The fouling potential of EfOM followed the order NaAg > NaAH > BSA; while EfOM on the membrane surface enhanced EDC removal in the order NaAH > BSA > NaAg. The mean retention rate of the membrane was increased by 24%, 10% and 8%, respectively. The properties of EDCs and EfOM cakes both influenced the EDC removal rates due to adsorption, size exclusion and charge attraction.

关键词： Endocrine disrupting chemicals Ultrafiltration Ozonation Effluent organic matters Secondary effluent

A system of general nonlinear variational inclusions in Banach spaces

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Applied Mathematics and Mechanics(English Edition) 2015年第12期36卷 1663-1672页

作者： Xieping ding SALAHUDDIN College of Mathematics and Software Science Sichuan Normal University Department of Mathematics Jazan University

A new system of general nonlinear variational inclusions is introduced and studied in Banach spaces. An iterative algorithm is developed and analyzed by use of the resolvent operator techniques to find the approximate solutions of the system of general nonlinear variational inclusions involving different nonlinear operators in uniformly smooth Banach spaces.

关键词： system of general nonlinear variational inclusions strongly accretive mapping relaxed accretive mapping resolvent operator uniformly smooth Banach space

数字人文视域下高校图书馆古籍数字化开发路径——以SW高校图书馆为例

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办公自动化 2025年第1期30卷 71-74页

作者：丁亚玲湖南生物机电职业技术学院长沙410127

文章旨在数字人文视域下,制定高效可行的古籍数字化策略,推动古籍资源的数字化保护与广泛利用。文章通过分析现有的古籍数字化项目,结合专家意见,针对不同古籍类型推荐适合的数字化技术和方法,考虑可持续发展和资源整合。文章强调整体... 详细信息

文章旨在数字人文视域下,制定高效可行的古籍数字化策略,推动古籍资源的数字化保护与广泛利用。文章通过分析现有的古籍数字化项目,结合专家意见,针对不同古籍类型推荐适合的数字化技术和方法,考虑可持续发展和资源整合。文章强调整体规划、技术创新及人才培养的重要性,并建议与各相关机构密切合作。研究成果为高校图书馆古籍开发提供具体的数字化实施指导,旨在通过跨学科合作,深化古籍的研究与教学应用,有效保护和利用珍贵古籍资源,为保护与传承文化遗产贡献力量。

关键词：数字人文高校图书馆古籍数字化开发路径可持续性发展

Cerium oxide nanoparticles-mediated cascade catalytic chemo-photo tumor combination therapy

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Nano Research 2022年第1期15卷 333-345页

作者： Zitao Hu Yin ding State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

ROS-based tumor therapy based on nanocatalytic medicine has recently been proposed for its ***,a safe and highly efficient strategy towards getting high enough ROS to kill the hypoxic cancer cells is still a great ***,we report a simple pH/H_()20_(2)-activatable,O_(2)-evolving,and ROS regulating doxorubicin(DOX)and indocyanine green(ICG)co-loading PEGylated polyaniline(PANI)coated CeOx@polyacrylic acid(PAA)nanoclusters for highly selective and optimized cancer combination *** can selectively and greatly enhance intracellular O_(2) and ROS levels in tumor region,which depends on two-step catalytic properties of nanoceria(Ce^(4+)/Ce^(3+)=3.46,neutral surface charge,mostly localize into the cytoplasm,pH 7.4-6.5,catalase-like catalytic agents convert to Ce^(4+)/Ce^(3+)=0.58,negative surface charge,mostly localize into the lysosomes,pH 5-4,oxidase-like catalytic agents,triggered by near infrared(NIA)laser irradiation).Furthermore,the protective effect of polyethylene glycol(PEG),PANI,and PAA ensure that the nanoceria can only play the role of catalase under the irradiation of NIR light arrived at the tumor ***,loading of nanoceria and ICG onto PANI greatly enhanced photo thermal effect of nanoparticles.(NPs),which is useful for killing cancer cells by relieving hypoxia and promoting cross-membrane drug *** further enhance photodynamic therapy and chemotherapy *** chemo-photo combination therapies fantastically inhibited tumor growth and prevented tumor recurrence in vivo,suggesting a smart nanotheranostic system to achieve more precise and effective therapies in O_(2)-deprived tumor tissue.

关键词： nanocatalytic medicine photodynamic therapy hypoxia cerium oxide@polyaniline combination therapy

Early development,life history and ecological habits of Grateloupia constricata Li et ding

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Acta Oceanologica Sinica 2020年第10期39卷 155-161页

作者： Yuanyuan ding Yao Bian Huina Wang Jing Liu Jingrui Li Hongwei Wang College of Life Sciences Liaoning Normal UniversityDalian 116000China

As the largest genus of Halymeniaceae,Grateloupia has been widely ***,we observed the life history and early development of Grateloupia constricata Li et ding and investigated the effects of temperature,irradiance,and photoperiod on the discoid crust and sporeling development of *** under laboratory *** observed that the type of carpospore development was“mediate discal type”.The life history included homotypic gametophyte(haploid),carposporophyte(diploid),and tetrasporophyte(diploid),with typical isomorphic alternation of *** results of double factorial analysis showed that both single factorial effects and interaction among temperature,photoperiod,and irradiance were obviously significant on the discoid crust and sporeling ***,we found that the optimum combination of condition for the early growth and development of *** was temperature 20°C,irradiance 80μmol photons/(m^2·s)and photoperiod 16L:*** study provides the theoretical basis and technical support for the conservation of the Grateloupia germplasm,artificial breeding,large-scale cultivation and sustainable development.

关键词： carpospore life history alternation of generations temperature irradiance photoperiod

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NES cell

Applied Mathematics and Mechanics(English Edition) 2022年第12期43卷 1793-1804页

作者： Hu ding Yufei SHAO Shanghai Key Laboratory of Mechanics in Energy Engineering School of Mechanics and Engineering ScienceShanghai UniversityShanghai200072China

A broadband adaptive vibration control strategy with high reliability and flexible versatility is *** high vibration damping performance of nonlinear energy sink(NES)has attracted ***,targeted energy transfer may cause severe vibration of ***,it is difficult to realize pure nonlinear stiffness without the linear *** a result,the reliability of NES is not *** low reliability of NES has hindered its application in *** addition,the performance of NES depends on its mass ratio of the primary system,and NES lacks versatility for different vibration ***,this paper proposes the concept of NES *** advantages of the adaptive vibration control of NES are applied to cellular *** applying a large number of NES cells in parallel,the reliability of NES and its versatility to complex vibration structures are *** elastic beam is used as the primary vibration structure,and a limited NES is used as the *** relationship between the vibration suppression effect of NES cells and the number of NES cell is *** addition,the effect of the distribution of NES cells on the multi-mode resonance suppression of the beam is also *** summary,the mode of the primary structure can be efficiently controlled by a large number of lightweight NES ***,the lightweight NES cell is flexible for vibration control of complex *** addition,it improves the reliability of NES ***,the distributed application of NES cells proposed in this paper is a valuable vibration suppression strategy.

关键词： vibration nonlinear energy sink(NES) NES cell vibration control clamped beam harmonic balance method(HBM)