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A Win-Win Effect for Both the Ferromagnetism and the Dopability of p-Type Doping in ZnO:(Cu+N)

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Chinese Physics Letters 2013年第8期30卷 144-147页

作者： wei Ling zhang wei-feng Key laboratory of Photovoltaic Techniques School of Physics&ElectronicsHenan UniversityKaifeng 475001

We investigate the electronic structures and magnetic properties of ZnO doped with N,Cu,and(Cu+N)by using a first principles method and considering the strong correlation *** is interesting to compare these three ***:N has weak p-type doping and unstable ferromagnetism,while ZnO:Cu becomes insulating due to the Jahn–Teller *** and N codoping can not only greatly improve the dopability of p-type doping accompanying the Jahn–Teller fading,but also enhance the ferromagnetism at the same *** calculation results indicate that there is a win-win effect between N and Cu dopants in the ZnO:(Cu+N)system,which could possibly find applications in spintronics besides optoelectronics.

关键词： effect dopant doping

Littlest Higgs Model and Higgs Boson Associated Production with Top Quark Pair at High Energy Linear e^＋e^- Collider

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Communications in Theoretical Physics 2006年第3期45卷 511-516页

作者： YUE Chong-Xing WANG wei zhang feng Department of Physics Liaoning Normal University Dalian 116029 China

In the parameter space allowed by the electroweak precision measurement data, we consider the contributions of the new particles predicted by the littlest Higga model to the Higgs hoson associated production with top quark pair in the future high energy linear e^＋e^- collider （ILU）. We find that the contributions mainly come from the new gauge bosons ZH and BH. For reasonable values of the free parameters, the absolute value of the relative correction parameter δσ/σ^SM can be signiticanly large, which might be observed in the future ILU experiment with √S = 800 GeV.

关键词： littlest Higgs model Higgs boson new gauge bosons

Sedimentation of short cylindrical pollutants with mechanical contacts

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Journal of Environmental Sciences 2005年第6期17卷 906-911页

作者： LIN Jian-zhong WANG Ye-long zhang wei-feng Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China Institute of Marine and Coastal Sciences Rutgers University New Brunswick New Jersey USA

Lattice Boltzmann method and elastic particle collision model were used to investigate the sedimentation of short cylindrical pollutant particles with mechanical contacts for varying bulk number density ε and terminal Reynolds number ReT. The corresponding experiments were performed as a comparison. The clusters of pollutant particles with an inverted “T” structure were observed, the pollutant particles for high ε and large ReT scattered wider than that for low ε and small ReT. The sedimentation velocities increased suddenly at the initial stage, then decreased drastically, after that swayed around and approached to a steady value. The time to steady state did not depend on ε and ReT. The effect of particle interactions was to hinder the average sedimentation velocity, and hindrance was directly proportional to ε. The orientation distributions of pollutant particles depended on ReT and ε, especially on the former. Both the standard deviations of vertical and horizontal velocity, the former was larger than the latter, were nearly independent on ε and ReT.

关键词： cylindrical pollutant particles sedimentation lattice-Boltzmann simulation experiment mechanical contact

为何·以何·如何:新时代推进党的自我革命的三维探赜

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青岛农业大学学报（社会科学版） 2024年第3期36卷 51-56页

作者：张峰玮王明春闽南师范大学马克思主义学院福建漳州363000

习近平总书记关于党的自我革命的重要思想是党的建设重大理论创新成果,表明了我们党对共产党执政规律认识达到一个新高度。推进党的自我革命是先进的马克思主义政党的内在要求,是百年大党发展的历史经验,是实现新的历史使命的现实需要,... 详细信息

习近平总书记关于党的自我革命的重要思想是党的建设重大理论创新成果,表明了我们党对共产党执政规律认识达到一个新高度。推进党的自我革命是先进的马克思主义政党的内在要求,是百年大党发展的历史经验,是实现新的历史使命的现实需要,是引领新时代伟大社会革命的实践要求;党的性质宗旨、初心使命、中华优秀传统文化的深厚积淀、完善的党内法规制度体系为推进党的自我革命提供源源不断的动力;新时代要围绕坚持党的领导、抓实理论学习、正风肃纪反腐、健全制度规范体系、建强干部人才队伍为路径继续推进党的自我革命。

关键词：习近平新时代党的自我革命实践路径

考虑三类客户点的卡车-无人机协同配送模型及混合算法

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供应链管理 2024年第7期5卷 33-46页

作者：狄卫民杨文豪张威风郑州大学管理学院河南郑州450001

为了提高“最后一公里”配送效率,降低配送成本,文章提出一种考虑三类客户点的卡车-无人机协同配送模式。建立以配送成本和配送时间的加权和最小化为目标的数学模型,对三类客户点在卡车-无人机协同配送路径、卡车和无人机载重、协同时... 详细信息

为了提高“最后一公里”配送效率,降低配送成本,文章提出一种考虑三类客户点的卡车-无人机协同配送模式。建立以配送成本和配送时间的加权和最小化为目标的数学模型,对三类客户点在卡车-无人机协同配送路径、卡车和无人机载重、协同时间以及无人机电量方面进行约束;使用由遗传算法、K-means聚类算法与构造算法共同组成的混合算法对模型求解。大规模算例和小规模算例结果显示本文算法求解效率和求解精度较高;以配送成本和配送时间的加权和最小化为目标对比以配送成本或配送时间最小化为目标结果更优。文章提出的模型和算法能有效解决卡车-无人机协同配送问题;以配送成本和配送时间的加权和最小化为目标相较于只考虑配送成本或配送时间更合理。

关键词：卡车-无人机协同配送遗传算法 K-means聚类算法构造算法

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老年钙化性心脏瓣膜病患者Crouse积分、IMT与瓣膜钙化程度的关系

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广东医学 2024年第4期45卷 463-466页

作者：蔡俊张富山张伟峰郑州市第七人民医院心外七科河南郑州450016

目的探讨老年钙化性心脏瓣膜病患者颈动脉斑块积分(Crouse积分)、内膜中层厚度(intima media thickness,IMT)与瓣膜钙化程度的关系。方法回顾性分析2020年4月至2023年3月收治的106例老年钙化性心脏瓣膜病患者的临床资料(观察组)。另选... 详细信息

目的探讨老年钙化性心脏瓣膜病患者颈动脉斑块积分(Crouse积分)、内膜中层厚度(intima media thickness,IMT)与瓣膜钙化程度的关系。方法回顾性分析2020年4月至2023年3月收治的106例老年钙化性心脏瓣膜病患者的临床资料(观察组)。另选择90例颈动脉粥样硬化的非心脏瓣膜病患者作为对照组1、选取95例非老年钙化性心脏瓣膜病患者作为对照组2。单因素方差分析检验三组Crouse积分、IMT、管腔狭窄程度及老年钙化性心脏瓣膜病不同心瓣膜钙化程度患者Crouse积分、IMT。Pearson分析Crouse积分、IMT与心瓣膜钙化程度的相关性;受试者工作特征(ROC)曲线分析Crouse积分、IMT对老年钙化性心脏瓣膜病患者瓣膜钙化的预测价值。结果观察组Crouse积分、IMT、管腔狭窄程度均明显高于对照组1和对照组2(P<0.05)。老年钙化性心脏瓣膜病不同心瓣膜钙化程度患者Crouse积分、IMT比较:1级<2级<3级(P<0.05)。相关性分析结果显示,Crouse积分、IMT与老年钙化性心脏瓣膜病瓣膜钙化程度均呈明显正相关关系(r=0.585、0.623,P<0.05)。绘制Crouse积分、IMT预测老年钙化性心脏瓣膜病患者瓣膜钙化的ROC曲线示,Crouse积分、IMT联合预测的AUC为0.802(95%CI为0.738~0.867),明显高于各指标单一预测的AUC,最佳诊断敏感度和特异度分别为0.887、0.794(P<0.05)。结论老年钙化性心脏瓣膜病患者Crouse积分、IMT存在异常增高,且与瓣膜钙化程度呈正相关,测量上述指标有助于对心脏瓣膜钙化程度进行评估。

关键词：老年钙化性心脏瓣膜病颈动脉斑块积分颈动脉内膜中层厚度瓣膜钙化

Continuous time Markov chain based website navigability measure

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The Journal of China Universities of Posts and Telecommunications 2011年第2期18卷 45-52页

作者： zhang wei-feng LIU Xia zhang Ying-zhou ZHOU Guo-qiang State Key Laboratory of Software Engineering Wuhan University Wuhan 430072 China School of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China

Website navigability is acquiring a growing importance in website design and redesign,quality evaluation,and *** navigability measures mainly depend on site link structure,so that they only consider the impact of site link structure for navigability and ignore the impact of Web page content.A continuous Markov chain model which depicts the user＇s surfing behavior can balance these two factors in the evaluation of website navigability,and it needs to estimate the page transition probabilities and user stay time according to user access *** this way,we can obtain more reliable results for website navigability measure than the existed *** show that our method is effective.

关键词： navigability measure Markov chain

Centralized light-wave WDM-PON employing DQPSK downstream and OOK remodulated upstream signals

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The Journal of China Universities of Posts and Telecommunications 2010年第4期17卷 125-128页

作者： zhang wei-feng XIN Xiang-jun zhang Qi zhang Zi-xing NAI wei SHI Yan School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

A novel architecture for wavelength-division-multiplexing passive optical network （WDM-PON） with centralized light-wave is proposed and demonstrated. At the optical line terminal （OLT） session of this architecture, optical differential quadrature phase shift keying （DQPSK） modulated signal with constant-intensity at 10 Gbit/s is utilized for downstream transmission. At the optical network unit （ONU）, part of the downstream optical power is remodulated with on-off keying （OOK） intensity modulation at 10 Gbit/s for upstream without additional laser. Simulation results show that the power penalties of the downstream for 20 km single-mode fiber （SMF） transmission and multi-channels are negligible. While for the upstream, the power penalties are obvious. The simulation results and analysis also reflect that by reducing the launch power of DQPSK transmitters, power penalties can be reduced, although the transmission distance is limited.

关键词： WDM-PON DQPSK remodulation centralizedlight sources

不同耕作方式与地膜覆盖对花生生理特性、产量及品质的影响

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花生学报 2024年第2期53卷 47-54,76页

作者：张伟锋吴会福王瑞杰柳玉芳郑玲山东省潍坊市农业技术推广中心山东潍坊261061 潍坊市潍城区乐埠山生态经济发展服务中心山东潍坊261021 昌乐县宝城街道农业农村综合服务中心山东昌乐262400 龙口市诸由观镇农业综合服务中心山东龙口265700 山东师范大学生命科学院山东济南250014

为优化花生栽培管理措施,进而提升花生产量和品质,本研究通过设置旋耕地膜覆盖(RTM),旋耕露地(RT),深耕地膜覆盖(DTM)以及深耕露地(DT)四个处理,系统研究了不同耕作方式和地膜覆盖对花生生理特性、产量及品质的影响。结果表明:深耕能够... 详细信息

为优化花生栽培管理措施,进而提升花生产量和品质,本研究通过设置旋耕地膜覆盖(RTM),旋耕露地(RT),深耕地膜覆盖(DTM)以及深耕露地(DT)四个处理,系统研究了不同耕作方式和地膜覆盖对花生生理特性、产量及品质的影响。结果表明:深耕能够改善花生的光合性能,与RTM处理相比,DTM处理在2021年结荚期、饱果期和收获期的叶片净光合速率平均提高了2.57%;此外,深耕有利于花生干物质积累量的增加,与RTM处理相比,DTM处理累积干物质积累量在2021年提高了3.09%。地膜覆盖可以提高花生根系活力、叶片SPAD值、叶面积指数和净光合速率,延缓植株衰老,改善籽仁品质;与DT处理相比,DTM处理在2021年结荚期、饱果期和收获期的根系活力和叶面积指数分别平均提高了11.70%和13.40%。DTM处理与RTM、DT和RT处理相比,2022年荚果产量分别显著提高了5.72%、8.27%和13.08%。综上,深耕地膜覆盖可作为实现花生高产优质生产目标的有效措施。

关键词：花生耕作方式地膜覆盖生理特性产量品质