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铁道机车与动车 2024年第5期 42-43页

作者：邹云庆中车洛阳机车有限公司襄阳分公司湖北襄阳441105

对柴油机在车体上定位原理进行分析,提出柴油机更换机体后,不用架车使用柴油机预装胎测量即可对柴油发电机组进行定位的一种简便办法,对此工艺方法进行探讨分析。

关键词： DF4型机车柴油机更换机体位置度

Biphenyl-Induced Superhelix in L-Phenylalanine-Based Supramolecular Self-Assembly with Dynamic Morphology Transitions

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CCS Chemistry 2022年第8期4卷 2816-2828页

作者： Laiben Gao Yueyue Feng Chao Xing Yu Zhao Meng Sun yunqing zou Changli Zhao Xiaoqiu Dou Chuanliang Feng State Key Lab of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240 College of Chemistry and Materials Science Shanghai Normal UniversityShanghai 200234 School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001

Dynamic transitions of supramolecular assemblies between lower-order structures and higher-order superhelical structures(e.g.,double-helical DNA,helical biopolymers)are of vital importance in many physiological processes,but still remain a great challenge to be realized in artificially assembled ***,a novel biphenyl central core symmetrically coupled with phenylalanine groups drives the construction of the dynamic superhelix.

关键词： superhelix biphenyl chirality morphological transition cell release

Simulation Study on the Heat Transfer Characteristics of a Spray-Cooled Single-Pipe Cooling Tower

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Fluid Dynamics & Materials Processing 2024年第9期20卷 2109-2126页

作者： Kaiyong Hu Zhaoyi Chen yunqing Hu Huan Sun Zhili Sun Tonghua zou Jinghong Ning Tianjin Key Lab of Refrigeration Technology Department of Refrigeration and Low Temperature EngineeringTianjin University of CommerceTianjin300134China Jiangsu Yongzhiyu Technology Development Co. Ltd.Xuzhou221700China Shandong Onar Refrigeration Technology Co. Ltd.Binzhou256600China

The current study focuses on spray cooling applied to the heat exchange components of a cooling *** optimization of such processes is attempted by assessing different spray flow rates and droplet *** simplicity,the heat exchanger of the cooling tower is modeled as a horizontal round tube and a cooling tower spray cooling model is developed accordingly using a computational fluid dynamics(CFD)*** study examines the influence of varying spray flow rates and droplet sizes on the heat flow intensity between the liquid layer on the surface of the cylindrical tube and the surrounding air,taking into account the number of *** is observed that on increasing the spray flow strength,the heat flow intensity and extent of the liquid film in the system are enhanced ***,the magnitude of droplet size significantly impacts heat transfer.A larger droplet size decreases evaporation in the air and enhances the deposition of droplets on the round *** facilitates the creation of the liquid film and enhances the passage of heat between the liquid film and *** the number of nozzles,while maintaining a constant spray flow rate,results in a decrease in the flow rate of each individual *** decrease is not favorable in terms of heat transfer.

关键词： Spray cooling droplet sizes number of nozzles CFD

Analyzing the Dissemination of News by Model Averaging and Subsampling

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Journal of Systems Science & Complexity 2024年第5期37卷 2104-2131页

作者： zou Jiahui School of Statistics Capital University of Economics and BusinessBeijing 100070China

The dissemination of news is a vital topic in management science,social science and data *** the development of technology,the sample sizes and dimensions of digital news data increase *** alleviate the computational burden in big data,this paper proposes a method to deal with massive and moderate-dimensional data for linear regression models via combing model averaging and subsampling *** author first samples a subsample from the full data according to some special probabilities and split covariates into several groups to construct candidate ***,the author solves each candidate model and calculates the model-averaging weights to combine these estimators based on this ***,the asymptotic optimality in subsampling form is proved and the way to calculate optimal subsampling probabilities is *** author also illustrates the proposed method via simulations,which shows it takes less running time than that of the full data and generates more accurate estimations than uniform ***,the author applies the proposed method to analyze and predict the sharing number of news,and finds the topic,vocabulary and dissemination time are the determinants.

关键词： Asymptotic optimality dissemination of news linear regression models model averaging optimal subsampling.

Conceptual transition from molecular to atomic: unleashing a new era in hydrogen therapy for chronic disease

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National Science Review 2024年第04期11卷 17-18页

作者： Zhigang zou Eco-materials and Renewable Energy Research Center (ERERC) Jiangsu Key Laboratory for Nano Technology National Laboratory of Solid State Microstructures and Department of PhysicsNanjing University

The dysregulated overexpression of reactive oxygen and nitrogen species (RONS)intricately links to the occurrence and development of diverse chronic diseases[1–3]. Hydrogen therapy stands out as a promising treatment methodology recognized for effectively mitigating RONS and maintaining intracellular redox equilibrium, thereby yielding therapeutic benefits [4,5].

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Image Fusion Based on Bioinspired Rattlesnake Visual Mechanism Under Lighting Environments of Day and Night Two Levels

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Journal of Bionic Engineering 2024年第3期21卷 1496-1510页

作者： Yong Wang Hongmin zou College of Communication Engineering Jilin UniversityChangchun130012China

This study,grounded in Waxman fusion method,introduces an algorithm for the fusion of visible and infrared images,tailored to a two-level lighting environment,inspired by the mathematical model of the visual receptive field of rattlesnakes and the two-mode cells'*** research presented here is segmented into three *** the first segment,we design a preprocessing module to judge the ambient light intensity and divide the lighting environment into two levels:day and *** second segment proposes two distinct network structures designed specifically for these daytime and nighttime *** the daytime images,where visible light information is predominant,we feed the ON-VIS signal and the IR-enhanced visual signal into the central excitation and surrounding suppression regions of the ON-center receptive field in the B channel,***,for nighttime images where infrared information takes precedence,the ON-IR signal and the Visual-enhanced IR signal are separately input into the central excitation and surrounding suppression regions of the ON-center receptive field in the B *** outcome is a pseudo-color fused *** third segment employs five different no-reference image quality assessment methods to evaluate the quality of thirteen sets of pseudo-color images produced by fusing infrared and visible *** images are then compared with those obtained by six other methods cited in the relevant *** empirical results indicate that this study's outcomes surpass the comparative results in terms of average gradient and spatial *** one or two sets of fused images underperformed in terms of standard deviation and entropy when compared to the control *** sets of fused images did not perform as well as the comparison in the QAB/F *** conclusion,the fused images generated through the proposed method show superior performance in terms of scene detail,visual perception,and image sharpness

关键词： Rattlesnake Visible image Infrared image Daylight Bionic

Security-Reliability Tradeoff Analysis for Jamming Aided Decode-and-Forward Relay Networks

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China Communications 2024年第5期21卷 218-228页

作者： zou Ronggui zou Yulong Zhu Jia Li Bin School of Telecommunications and Information Engineering Nanjing University of Posts and TelecommunicationsNanjing 210003China

In this paper,we explore a cooperative decode-and-forward(DF)relay network comprised of a source,a relay,and a destination in the presence of an *** improve physical-layer security of the relay system,we propose a jamming aided decodeand-forward relay(JDFR)scheme combining the use of artificial noise and DF relaying which requires two stages to transmit a ***,in stage one,the source sends confidential message to the relay while the destination acts as a friendly jammer and transmits artificial noise to confound the *** stage two,the relay forwards its re-encoded message to the destination while the source emits artificial noise to confuse the *** addition,we analyze the security-reliability tradeoff(SRT)performance of the proposed JDFR scheme,where security and reliability are evaluated by deriving intercept probability(IP)and outage probability(OP),*** the purpose of comparison,SRT of the traditional decode-and-forward relay(TDFR)scheme is also *** results show that the SRT performance of the proposed JDFR scheme is better than that of the TDFR ***,it is shown that for the JDFR scheme,a better SRT performance can be obtained by the optimal power allocation(OPA)between the friendly jammer and user.

关键词： decode-and-forward relay friendly jammer physical layer security power allocation security-reliability tradeoff

Design of Robust Var Reserve Contract for Enhancing Reactive Power Ancillary Service Market Efficiency

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 767-771页

作者： Yunyang zou Yan Xu School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore

In a deregulated Var market, market power issue is more serious than in an energy market since reactive power cannot be transmitted over long distances. This letter designs a multi-timescale Var market framework, where market power that may arise in the hourly-ahead Var support service market due to system configuration deficiency and market structure flaws can be eliminated by day-ahead contract-based Var reserve service market. Settlement of day-ahead Var reserve contract is formulated as a two-stage robust optimization (TSRO) model considering worst case of uncertainty realization and potential market power that may arise in hourly-ahead market. TSRO with integer recourses is then solved by a new column and constraint generation algorithm. Results show a robust Var reserve contract can fully eliminate market power, and prevent suppliers from manipulating market prices.

关键词： Market efficiency market power reactive power ancillary service two-stage robust optimization Var reserve

Dynamic Development Characteristics and Driving Factors of High Quality Development Level in China’s Five Major Urban Agglomerations

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Chinese Geographical Science 2024年第5期34卷 777-790页

作者： zou Weiyong XU Lingli School of Economics Guangdong Ocean UniversityZhanjiang 524088China School of Economics Shanghai UniversityShanghai 200444China

High-quality development is the primary task of comprehensively building a socialist,modern country,as well as the primary task of building urban agglomerations in *** on the five development concepts,this paper used the entropy method to measure the High Quality Development Index(HQDI)of the five major urban *** results showed that the HQDI of the five major urban agglomerations shows a fluctuating upward ***,using the Dagum Gini coefficient to explore the sources of HQDI development differences in urban agglomerations,we found that the main source of HQDI differences in urban agglomerations was inter-regional differences,while intra-regional differences were not ***,kernel density estimation was used to test the dynamic evolution trend of HQDI within urban *** was a polarisation phenomenon in the HQDI of urban agglomerations,such as the Pearl River Delta urban agglomeration and the Chengdu-Chongqing urban *** overall,the degree of imbalance had ***,using geographic detectors to examine the driving factors of HQDI in urban agglomerations,we found that the main driving forces for improving HQDI in urban agglomerations were economic growth,artificial intelligence technology and fiscal *** the interaction factors had greater explanatory power for the spatial differentiation of HQDI,which can be divided into two types:two-factor improvement and non-linear *** study is conducive to improving and enriching the theoretical system for evaluating the high quality development of urban agglomerations,and provides policy references for promoting the high quality development of urban agglomerations.

关键词： urban agglomeration High Quality Development Index(HQDI) spatio-temporal evolution driving factors

Forming process chain for manufacturing complex conical-section profiled rings:On a co-design method

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Chinese Journal of Aeronautics 2024年第6期37卷 485-503页

作者： Lei LIANG Chaojiang zou Lianggang GUO State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Guizhou Aviation Technology Development Co.Ltd Guiyang 550081China

The final quality of complex conical-section rings depends on co-design of multiple processes in forming process *** this study,for a complex aeroengine casing ring with a large slope and a flange on its end,a co-design method of the forming process chain is put forward towards the objective of precision forming,which not only proposes a standard process route composed of multiple processes of upsetting,punching,rectangular ring rolling,loose tooling forging and profiled ring rolling,but also presents co-design methods of dies and blanks for all the *** profiled ring rolling,a design method of preformed blank that makes the blank and the target conical-section ring have the same axial volume distribution is *** the method,the axial metal redistribution during the process can be alleviated greatly thus improving the forming stability and precision of the *** on the geometric features of designed preformed blank,design methods of blanks and dies for loose tolling forging,rectangular ring rolling,punching and upsetting are proposed *** view of the key roles of loose tooling forging(manufacturing the preformed blank)and profiled ring rolling on the final quality of the conical ring parts,inherited FE simulations for these two processes are performed to verify the proposed design methods and determine appropriate design *** is demonstrated that the proposed design method has significant advantages in improving forming ***,a suggestive value 1.5 of the rolling ratio for profiled ring rolling(a key design parameter)is given based on comprehensive consideration of multiple indicators such as ring roundness,deformation uniformity and forming *** corresponding industrial experiments performed illustrate that a high forming precision of the conical-section aeroengine casing ring is achieved.

关键词： Complex conical-section ring Co-design of forming process chain Profiled ringrolling Preformed blank Loose tooling forging