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沙区铁路道岔防风沙设计研究综述

铁道建筑 2025年第1期65卷 38-44页

作者：丁东王勇岳帅井国庆长安大学公路学院西安710064 北京交通大学土木建筑工程学院北京100044

在荒漠地区,铁路道岔受到风沙侵蚀和掩埋的威胁,影响列车运行安全。本文系统梳理了国内外关于道岔结构优化、防沙措施、清沙技术以及智能监测技术研究的最新进展。结果表明:道岔结构优化,包括改进钢轨材料、使用新型滑床板、动态轨距调... 详细信息

在荒漠地区,铁路道岔受到风沙侵蚀和掩埋的威胁,影响列车运行安全。本文系统梳理了国内外关于道岔结构优化、防沙措施、清沙技术以及智能监测技术研究的最新进展。结果表明:道岔结构优化,包括改进钢轨材料、使用新型滑床板、动态轨距调整技术以及轨枕道床结构优化,可以显著提高轨道耐磨损能力,避免道岔堵塞和道床沙化;采用通用防沙工程、道岔挡沙刷、防沙盖板等防沙措施,可以有效在沙源和传输路径进行防沙,优化道岔流场,减少沙砾堆积;引入高效的除沙机具和智能监测技术,如传感器、无人机巡检以及图像识别技术,能够实现道岔状态的实时监测、线路积沙情况监测和及时沙害处理。

关键词：沙区铁路道岔结构优化防沙措施清沙技术智能监测

芦荟提取物治疗鸡柔嫩艾美耳球虫感染的效果研究

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中国家禽 2025年第2期47卷 60-65页

作者：丁咚吴楠宋臣锋刘勇沧州师范学院河北沧州061000 沧州医学高等专科学校河北沧州061000 沧州职业技术学院河北沧州061000 河北省国富农业投资集团有限公司河北石家庄050000

为评价芦荟提取物对鸡柔嫩艾美耳球虫的治疗效果,试验将14日龄180只雏鸡随机分为6组,即阴性对照组(不感染球虫不给药)、阳性对照组(感染球虫不给药)、地克珠利治疗组(0.2 mL/L地克珠利)、芦荟提取物低(0.5 g/L)、中(1 g/L)、高(2 g/L)... 详细信息

为评价芦荟提取物对鸡柔嫩艾美耳球虫的治疗效果,试验将14日龄180只雏鸡随机分为6组,即阴性对照组(不感染球虫不给药)、阳性对照组(感染球虫不给药)、地克珠利治疗组(0.2 mL/L地克珠利)、芦荟提取物低(0.5 g/L)、中(1 g/L)、高(2 g/L)剂量治疗组,每组3个重复,每个重复10只鸡。除阴性对照组外,其余试验组鸡只经口人工感染7.5×10^(4)个柔嫩艾美耳球虫孢子化卵囊,并在感染球虫当天所有治疗组开始饮水给药,直至试验结束。所有试验鸡在21日龄统计相对增重率、存活率、盲肠病变值、卵囊值,计算抗球虫指数(ACI),综合评价芦荟提取物的抗球虫效果。结果显示:与阳性对照组相比,芦荟提取物组试验鸡相对增重率和存活率均有所提高,盲肠病变记分和每克粪便卵囊数(OPG)显著降低(P<0.05);芦荟提取物高、中、低剂量组均达到低效抗球虫效果,ACI分别为154.23、145.94、122.93;地克珠利治疗组达到高效抗球虫效果,ACI为181.55。研究表明,在饮水中添加2 g/L芦荟提取物对鸡球虫病的治疗有一定效果。

关键词：芦荟提取物鸡柔嫩艾美耳球虫治疗效果

Inhomogeneous Cauchy-Riemann equation in Octonion space

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Applied Mathematics(A Journal of Chinese Universities) 2015年第4期30卷 447-452页

作者： GONG ding-dong Department of Mathematical Science Zhejiang Sci-Tech University

The integral representation of differentiable functions in Octonion space is obtained and the explicit solution of the inhomogeneous Cauchy-Riemann equation is given by integral representation. As an application, the ... 详细信息

关键词： Octonion integral representation of differentiable functions inhoraogeneous Cauchy-RiemannEquation Cousin problem.

A Novel Fine-Grained Method for Vehicle Type Recognition Based on the Locally Enhanced PCANet Neural Network

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Journal of Computer Science & Technology 2018年第2期33卷 335-350页

作者： Qian Wang You-dong ding School of Computer Enqineering and Science Shan qhai University Shanqhai 200072 China Information Center Criminal Investigation Department of Shanghai Public Security Bureau Shanghai 200083 China Shanghai Engineering Research Center of Motion Picture Special Effects Shanghai 200072 China Shanghai Film Academy Shanghai University Shanghai 200072 China

In this paper, we propose a locally enhanced PCANet neural network for fine-grained classification of vehicles. The proposed method adopts the PCANet unsupervised network with a smaller number of layers and simple parameters compared with the majority of state-of-the-art machine learning methods. It simplifies calculation steps and manual labeling, and enables vehicle types to be recognized without time-consuming training. Experimental results show that compared with the traditional pattern recognition methods and the multi-layer CNN methods, the proposed method achieves optimal balance in terms of varying scales of sample libraries, angle deviations, and training speed. It also indicates that introducing appropriate local features that have different scales from the general feature is very instrumental in improving recognition rate. The 7-angle in 180° （12-angle in 360°） classification modeling scheme is proven to be an effective approach, which can solve the problem of suffering decrease in recognition rate due to angle deviations, and add the recognition accuracy in practice.

关键词： fine-grained classification PCANet local enhancement vehicle type recognition

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数字化赋能学校课后服务高质量发展研究

教学与管理 2025年第4期 16-20页

作者：丁亚东李晓阳李静中国矿业大学公共管理学院江苏徐州221116

数字化通过技术赋能、价值赋能、组织赋能三大作用机制助力课后服务,实现治理体系的集成化、供给体系的网络化、评价体系的智能化,以及育人体系的精准化,推动课后服务全方位、多维度、立体化的高质量发展。然而调查发现,在数字化课后服... 详细信息

数字化通过技术赋能、价值赋能、组织赋能三大作用机制助力课后服务,实现治理体系的集成化、供给体系的网络化、评价体系的智能化,以及育人体系的精准化,推动课后服务全方位、多维度、立体化的高质量发展。然而调查发现,在数字化课后服务的运行实践中存在数字鸿沟的风险与挑战。基于此,提出从政策端、应用端以及价值端落实各方主体责任,同步推进课后服务的数字化转型。

关键词：数字化赋能课后服务高质量发展数字鸿沟

Stride Strategy to Enable a Quasi-ergodic Search of Reaction Pathways Demonstrated by Ring-opening Polymerization of Cyclic Esters

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Chinese Journal of Polymer Science 2023年第5期41卷 745-759,I0009页

作者： Wei-Han Rao Lin Yu Jian-dong ding State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China

Coordination-insertion ring-opening polymerization(ROP)of cyclic esters is an industrial way to synthesize polyesters,which are widely applied in biomedical and environment-benign ***,the rate-determining transition state(TS)identified by the conventional reaction pathways(pathway A and pathway B)presented in the literature did not well describe the structure-reactivity *** misidentification of the rate-determining TS might arise from the less ergodicity in the search of reaction ***,we suggested a stride strategy based on the insight that even a partial double bond is rotatable at the catalysis *** a result,we revealed a new reaction pathway,pathway C with a torsion transition state TSC2,by density functional theory(DFT).We also carried out kinetic experiments of ROP of D-lactide(D-LA),L-lactide(L-LA),ε-caprolactone(CL),andδ-valerolactone(VL),using poly(ethylene glycol)as the initiator and stannous octoate as the *** excellent linearity between the calculated free energy barriers and logarithms of the experimental kinetic constants of the two kinds of lactide and lactone monomers,was established,validating the quasi-ergodic search of reaction pathways and the scaling predicted by transition state *** linearity was highly predictive for the other lactide and lactone monomers,demonstrated by glycolide(GA)and trimethylene urethane(TU).

关键词： Coordination-insertion mechanism Ring-opening polymerization Density functional theory Biodegradable polymer Lactide Lactone Cyclic ester

Two Avowable Quantum Communication Schemes

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Communications in Theoretical Physics 2008年第11期50卷 1109-1112页

作者： YAN Feng-Li ding dong College of Physics Science and Information Engineering Hebei Normal University Shijiazhuang 050016 China North China Institute of Science and Technology Langfang 101601 China

Two avowable quantum communication schemes are *** is an avowable teleportation protocolbased on the quantum *** this protocol one teleports a set of one-particle states based on the availabilityof an honest arbitrator,the keys and the Einstein-Podolsky-Rosen pairs shared by the communication parties and *** key point is that the fact of the teleportation can neither be disavowed by the sender nor be denied bythe *** is an avowable quantum secure direct communication scheme.A one-way Hash function chosenby the communication parties helps the receiver to validate the truth of the information and to avoid disavowing for thesender.

关键词： avowable teleportation avowable quantum secure direction communication EPR pairs Hash function

Entangler and analyzer for multiphoton Greenberger-Horne-Zeilinger states using weak nonlinearities

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Science China(Physics,Mechanics & Astronomy) 2014年第11期57卷 2098-2103页

作者： ding dong YAN FengLi GAO Ting College of Physics Science and Information Engineering Hebei Normal University Department of Basic Curriculum North China Institute of Science and Technology College of Mathematics and Information Science Hebei Normal University

In the regime of weak nonlinearity we present two general,feasible schemes for manipulating photon *** is an entangler for generating any one of the n-photon Greenberger-Horne-Zeilinger(GHZ)*** of the incoming photons with crossKerr media followed by a phase shift gate and a measurement on a probe beam plus appropriate local operations using classical feed-forward of the measurement results allow one to obtain the desired states in a nearly deterministic *** second scheme discussed is an analyzer for multiphoton maximally entangled states,which is derived from the above *** this scheme,all of the 2nn-photon GHZ states can,nearly deterministically,be discriminated.

关键词： entangled photon entanglement generating coherent operations deterministic desired superposition optics

Static Recrystallization Behavior of SA508-III Steel during Hot Deformation

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Journal of Iron and Steel Research International 2016年第5期23卷 466-474页

作者： ding-qian dong Fei CHEN Zhen-shan CUI Institute of Forming Technology and Equipment Shanghai Jiao Tong University College of Manufacturing Science and Engineering Southwest University of Science and Technology

The static recrystallization behavior of SA508-III steel was investigated by isothermal double-hit hot compression tests at the deformation temperature of 950-1 250 ℃,the strain rate of 0. 01-1 s^（-1）,and the inter-pass time of 1-300 *** effects of deformation parameters,including forming temperature,strain rate,degree of deformation（ pre-strain） and initial austenite grain size,on the softening kinetics were analyzed. Experimental results show that static recrystallization kinetics is strongly dependent on deformation temperature and degree of deformation,while less affected by the strain rate and initial grain size. The kinetics and microstructural evolution equations of static recrystallization for SA508-III steel were developed to predict the softening behavior and the statically recrystallized grain size,respectively. Based on the comparison between the experimental and predicted results,it is found that the established equations can give a reasonable estimate of the static softening behavior for SA508-III steel.

关键词： softening fraction static recrystallization kinetic equation microstructure SA508-III steel