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原子与分子物理学报 2025年第4期42卷 27-32页

作者： XU Jian-Qiang MA zhao-peng CHENG Si LIU Zhi-Cong ZHU Guang-Lai Department of Physics School of Physics and Electronic InformationAnhui Normal UniversityWuhu 241002China

The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this *** following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution *** results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient ***,the excess molar volume initially decreases,reaches a minimum,and then *** rules of radial distribution functions(RDFs)of characteristic atoms are *** increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then *** indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently.

关键词： Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions

有氧运动对心肌梗死患者内皮祖细胞动员和功能的影响

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中国组织工程研究 2025年第23期29卷 4947-4955页

作者：赵鹏王聪聪王晨宇郑州澍青医学高等专科学校河南省郑州市450064 中国人民武装警察部队后勤学院卫生勤务系天津市300309 郑州航空工业管理学院河南省郑州市450015

背景:运动康复是心肌梗死患者非药物治疗的重要手段,能够改善心肌灌注和心血管功能,其机制可能与血管内皮细胞介导的血管新生与修复有关,而内皮祖细胞是血管内皮细胞的前体细胞。目的:探讨12周有氧运动对心肌梗死患者内皮祖细胞动员和... 详细信息

背景:运动康复是心肌梗死患者非药物治疗的重要手段,能够改善心肌灌注和心血管功能,其机制可能与血管内皮细胞介导的血管新生与修复有关,而内皮祖细胞是血管内皮细胞的前体细胞。目的:探讨12周有氧运动对心肌梗死患者内皮祖细胞动员和功能的影响。方法:(1)选择2022年1-10月在郑州大学第一附属医院接受经皮冠状动脉介入治疗后的急性心肌梗死患者66例,按照随机数字表法分为运动组(n=33)和对照组(n=33),对照组患者接受常规心脏康复治疗12周,运动组患者接受常规心脏康复+12周有氧运动干预。干预前及干预结束后72 h,检测患者心肺适能、纽约心脏协会分级、左心室射血分数、血清肌钙蛋白Ⅰ和脑钠肽水平及外周血内皮祖细胞数量。(2)干预前及干预结束后72 h,从两组患者外周血中分离提取内皮组细胞,检测内皮组细胞的增殖、黏附和迁移能力。结果与结论:(1)干预结束后72 h,运动组患者的纽约心脏协会分级、血清肌钙蛋白Ⅰ和脑钠肽水平均低于干预前、对照组(P<0.05),峰值摄氧量、最大功率、递增负荷试验完成时间、峰值运动时左心室射血分数高于干预前、对照组(P<0.05),平均心率和平均主观疲劳感觉评分低于干预前、对照组(P<0.05),外周血内皮组细胞数量多于干预前、对照组(P<0.05);(2)干预结束后72 h,运动组患者外周血内皮祖细胞的增殖、黏附与迁移能力均高于干预前、对照组(P<0.05);(3)结果表明,规律有氧运动能够促进内皮祖细胞动员并增强其增殖、黏附和迁移能力,进而改善心肌梗死患者临床病情、心功能和心肺适能。

关键词：心肌梗死有氧运动内皮祖细胞血管生成心功能心肺适能

MULTIVARIATE LIKELIHOOD RATIO ORDERING OF CONDITIONAL ORDER STATISTICS

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Journal of Systems Science & Complexity 2010年第6期23卷 1143-1152页

作者： Yashi WANG peng zhao Department of Science and Technology China University of Political Science and Law Beijing 100027 China School of Mathematics and Statistics Lanzhou University Lanzhou 730000 China.

Multivariate likelihood ratio order of order statistics conditioned on both the right tail and the left tail are built. These results strengthen and generalize those conclusions in terms of the univariate likelihood ratio order by Khaledi and Shaked （2007）, Li and zhao （2006）, Hu, et al. （2006）, and Hu, Jin, and Khaledi （2007）.

关键词： Conditional order statistics inactive time MTP2 multivariate likelihood ratio order residual lifetime.

Scalable and Adaptive Joins for Tra jectory Data in Distributed Stream System

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Journal of Computer Science & Technology 2019年第4期34卷 747-761页

作者： Jun-Hua Fang peng-peng zhao An Liu Zhi-Xu Li Lei zhao Institute of Artificial Intelligence School of Computer Science and TechnologySoochow UniversitySuzhou 215006ChinaNeusoft CorporationShenyang 110179China Institute of Artificial Intelligence School of Computer Science and TechnologySoochow UniversitySuzhou 215006China

As a fundamental operation in LBS(location-based services),the trajectory similarity of moving objects has been extensively studied in recent ***,due to the increasing volume of moving object trajectories and the demand of interactive query performance,the trajectory similarity queries are now required to be processed on massive datasets in a real-time *** work has proposed distributed or parallel solutions to enable large-scale trajectory similarity ***,those techniques cannot be directly adapted to the real-time scenario as it is likely to generate poor balancing performance when workload variance occurs on the incoming trajectory *** this paper,we propose a new workload partitioning framework,ART(Adaptive Framework for Real-Time Trajectory Similarity),which introduces practical algorithms to support dynamic workload assignment for RTTS(real-time trajectory similarity).Our proposal includes a processing model tailored for the RTTS scenario,a load balancing framework to maximize throughput,and an adaptive data partition manner designed to cut off unnecessary network *** on this,our model can handle the large-scale trajectory similarity in an on-line scenario,which achieves scalability,effectiveness,and efficiency by a single *** studies on synthetic data and real-world stream applications validate the usefulness of our proposal and prove the huge advantage of our approach over state-of-the-art solutions in the literature.

关键词： real-time data processing distributed computing trajectory similarity load balancing

Amine-Actuated Catalyst Switch for One-Pot Synthesis of Ether-Ester Type Block Copolymers

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Chinese Journal of Polymer Science 2024年第12期42卷 1925-1932,I0008页

作者： Hong Qiu peng-Fei Zhang Jun-peng zhao Faculty of Materials Science and Engineering South China University of TechnologyGuangzhou 510640China

Organocatalysis has shown special potency for simplifying the construction of complex polymer *** are reporting here a one-pot synthetic pathway using amine as a selectivity-switching agent in the two-component catalytic system consisting of triethylborane(Et_(3)B)and a phosphazene *** first modelled the interactions of a variety of amines with Et_(3)B by density functional theory *** results indicate that the aliphatic diamines comprising both primary and tertiary amino groups,capable of forming stable intramolecular hydrogen bonds,undergo the strongest complexation with Et_(3)***,experimental results demonstrate that the addition of such amines promptly actuates the in situ selectivity switch from Lewis pair-catalyzed ring-opening polymerization(ROP)of epoxide(propylene oxide,n-butylglycidyl ether,or glycidyl phenyl ether)to organobase-catalyzed ROP ofδ-valerolactone,allowing one-pot continuous synthesis of ether-ester type block *** thus exploited the noncovalent interaction between amine and Et_(3)B to refine the catalyst switch strategy by exempting it from loading of extra catalyst.

关键词： Ring-opening polmerization Block copolymers Organocatalysis

Improved data gap-filling schemes for estimation of net ecosystem exchange in typical East-Asian croplands

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Science China Earth Sciences 2016年第8期59卷 1652-1664页

作者： zhao peng Johannes LüERS Department of Micrometeorology University of Bayreuth Institute of Ecology University of Innsbruck Member of Bayreuth Center of Ecology and Environmental Research (BayCEER) University of Bayreuth

The estimation of carbon exchange between ecosystems and the atmosphere suffers unavoidable data gaps in eddy-covariance technique, especially for short-living and fast-growing croplands. In this study we developed a modified gap-filling scheme introducing a leaf area index factor as the vegetation status information based on the conventional light response function for two East-Asian cropland sites (rice and potatoes). This scheme’s performance is comparable to the conventional time window scheme, but has the advantage when the gaps are large compared to the total length of the time series. To investigate how the time binning approach performs for fast-growing croplands, we tested different widths of the time window, showing that a four-day window for the potato field and an eight-day time window for the rice field perform the best. The insufficiency of the conventional temperature binning approach was explained as well as the influence of vapor pressure deficit. We found that vapor pressure deficit plays a minor role in both the potato and the rice fields under Asian monsoon weather conditions with the exception of the early pre-monsoon growing stage of the potatoes. Consequently, we recommend using the conventional time-window scheme together with our new leaf-light response function to fill data gaps of net ecosystem exchange in fast-growing croplands.

关键词： Eddy-covariance Gap-filling Net ecosystem exchange LAI

Wood species identification using spectral reflectance feature and optimal illumination radian design

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Journal of Forestry Research 2016年第1期27卷 219-224页

作者： peng zhao Jun Cao Information and Computer Engineering College Northeast Forestry University College of Mechanical and Electronic Engineering Northeast Forestry University

We developed a scheme based on wood surface novel wood recognition spectral features that aimed to solve three problems. First was elimination of noise in some bands of wood spectral reflection curves. Second was improvement of wood feature selection based on analysis of wood spectral data. The wood spectral band is 350-2500 nm, a 2150D vector with a spectral sampling interval of 1 nm. We developed a feature selection proce- dure and a filtering procedure by solving the eigenvalues of the dispersion matrix. Third, we optimized the design for the indoor radian＇s mounting height. We used a genetic algorithm to solve the optimal radian＇s height so that the spectral reflection curves had the best classification infor- mation for wood species. Experiments on fivecommon wood species in northeast China showed overall recogni- tion accuracy 〉95 % at optimal recognition velocity.

关键词： Wood species identification Featureselection Radian Genetic algorithm Spectral analysis

Joint Optimization of Admission Control and Rate Adaptation for Video Sharing over Multirate Wireless Community Cloud

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China Communications 2016年第8期13卷 24-40页

作者： peng zhao Xinyu Yang Department of Computer Science and Technology Xi'an Jiaotong University

Emerging wireless community cloud enables usergenerated video content to be shared and consumed in a social context. However, the nature of shared wireless medium and timevarying channels seriously limits the quality of service(QoS), partially owing to the lack of mechanisms for effectively utilizing multi-rate channel resources. In this paper, the joint optimization of admission control and rate adaptation is proposed, resulting in a bandwidth-aware rate-adaptive admission control(BRAC) scheme to provide bandwidth guarantee for sharing social multimedia contents. The analytical approach leads to the following major contributions:(1) a bandwidth-aware rate selection(BRS) algorithm to optimally meet the bandwidth requirement of the data session and channel conditions at the physical layer;(2) a routing-coupled rate adaption and admission control algorithm to admit data sessions with bandwidth guarantee. Moreover, extensive numerical simulations suggest that BRAC is efficient and effective in meeting the bandwidth requirements for sharing social multimedia contents. These insights will shed light on communication system implementation for multimedia content sharing over multirate wireless community cloud.

关键词： wireless community cloud multirate rate adaptation bandwidth guarantee admission control

ATLRec:An Attentional Adversarial Transfer Learning Network for Cross-Domain Recommendation

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Journal of Computer Science & Technology 2020年第4期35卷 794-808页

作者： Ying Li Jia-Jie Xu peng-peng zhao Jun-Hua Fang Wei Chen Lei zhao School of Computer Science and Technology Soochow UniversitySuzhou 215006China

Entity linking is a new technique in recommender systems to link users'interaction behaviors in different domains,for the purpose of improving the performance of the recommendation ***-based cross-domain recom-mendation aims to alleviate the data sparse problem by utilizing the domain-sharable knowledge from auxiliary ***,existing methods fail to prevent domain-specific features to be transferred,resulting in suboptimal *** this paper,we aim to address this issue by proposing an adversarial transfer learning based model ATLRec,which effec-tively captures domain-sharable features for cross-domain *** ATLRec,we leverage adversarial learning to generate representations of user-item interactions in both the source and the target domains,such that the discrimina-tor cannot identify which domain they belong to,for the purpose of obtaining domain-sharable *** each domain learns its domain-specific features by a private feature *** recommendation of each domain considers both domain-specific and domain-sharable *** further adopt an attention mechanism to learn item latent factors of both domains by utilizing the shared users with interaction history,so that the representations of all items can be learned sufficiently in a shared space,even when few or even no items are shared by different *** this method,we can represent all items from the source and the target domains in a shared space,for the purpose of better linking items in different domains and capturing cross-domain item-item relatedness to facilitate the learning of domain-sharable *** proposed model is evaluated on various real-world datasets and demonstrated to outperform several state-of-the-art single-domain and cross-domain recommendation methods in terms of recommendation accuracy.

关键词： adversarial transfer learning attention mechanism cross-domain recommendation entity linking

An Improved Spectral Analysis Method for Fatigue Damage Assessment of Details in Liquid Cargo Tanks

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China Ocean Engineering 2018年第1期32卷 62-73页

作者： zhao peng-yuan HUANG Xiao-ping Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai Jiao Tong University

Errors will be caused in calculating the fatigue damages of details in liquid cargo tanks by using the traditional spectral analysis method which is based on linear system, for the nonlinear relationship between the dynamic stress and the ship acceleration. An improved spectral analysis method for the assessment of the fatigue damage in detail of a liquid cargo tank is proposed in this paper. Based on assumptions that the wave process can be simulated by summing the sinusoidal waves in different frequencies and the stress process can be simulated by summing the stress processes induced by these sinusoidal waves, the stress power spectral density(PSD) is calculated by expanding the stress processes induced by the sinusoidal waves into Fourier series and adding the amplitudes of each harmonic component with the same frequency. This analysis method can take the nonlinear relationship into consideration and the fatigue damage is then calculated based on the PSD of stress. Take an independent tank in an LNG carrier for example, the accuracy of the improved spectral analysis method is proved much better than that of the traditional spectral analysis method by comparing the calculated damage results with the results calculated by the time domain method. The proposed spectral analysis method is more accurate in calculating the fatigue damages in detail of ship liquid cargo tanks.

关键词： liquid cargo tank nonlinear system fatigue damage spectral analysis method dynamic pressure