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预警雷达反隐身技术顶层设计

西北工业大学学报 2014年第6期32卷 956-961页

作者：王伟伦王仲雷西北工业大学陕西西安710072

从雷达总体设计的角度出发,提出了一系列预警雷达反隐身举措,并做了初步分析。这些举措是短波宽脉冲发射、空间功率合成、多/双基地接收、扇扫合成孔径及脉冲压缩。所有这些举措旨在提高E/N0,并兼容于同一雷达中。

关键词：反隐身空间功率合成扇扫合成孔径顶层设计

Studies on the Dynamics of Endogenous GAs, ABA and IAA in the Shoot Apex of Chinese Pine in Relation to Male Cone Bud Initiation

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北京林业大学学报 1992年第S2期14卷 55-63页

作者： Yin weilun Jin Youju wang ShashengForest Resources College, Beijing Forestry UniversityZhang YunzhongBeijing Botanical Garden. Beijing 100093

The endogenous GAs, ABA and IAA in the shoot apices of 8-year-old Chinese pines, flowered, non-flowered and non-flowered but treated with GA4/7 were analyzed by *** results demonstrated that GA3 and GA9 levels were obviously higher in flowered plants than in non-flowered. A peak value of GA3 in flowered plants occurred after appearance of the earliest auxiliary bud primorda which had the possibility of transforming into male cone bud primordia and before the morphological initiation of male cone bud primordia. Exogenously applied GA4/7 could enhance the endogenous GA3 and GA9, this may benefit the promotion of male cone buds in Chinese pine. The relations among ex-ogenously applied GA4/7 endogenous GAs, ABA and IAA in the shoot apices, and the initiation of male cone bud are discussed.

关键词： Chinese pine flowering promotion male cone bud initiation exogenously applied GA4/7. endogenous GAs ABA IAA GC-MS-SIM analysis

Robust transmission expansion planning model considering multiple uncertainties and active load

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Global Energy Interconnection 2021年第5期4卷 476-484页

作者： Wensheng Li Long Zhao Yin Bo weilun wang Mingqiang wang Shuai Liu Rui Liu Xian wang Economic&Technology Research Institute State Grid Shandong Electric Power CompanyJinan 250021Shandong ProvinceP.R China Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Shandong UniversityJinan 250061Shandong ProvinceP.R China Global Energy Interconnection Group Co. Ltd.Xicheng District100031BeijingP.R.China

Uncertainty must be well addressed in transmission expansion planning(TEP)problem,and it significantly affects the reliability and cost-effectiveness of power *** to the complex operating environment of power systems,it is crucial to consider different types of uncertainties during the planning *** this paper,a robust TEP model is proposed by considering multiple uncertainties and active ***,in this model,the uncertainties of wind power output and contingency probability are considered *** uncertainties are described by scenario and interval,and the Benders decomposition technique is applied to solve the *** feasibility and effectiveness of the proposed model are illustrated using the IEEE RTS and IEEE 118-node systems.

关键词： Benders decomposition Transmission expansion planning Robust optimization Uncertainty

Resistance of Cement Paste and Its Relationship to Strength under the Corrosive Action of Ambient Media

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Engineering（科研） 2012年第6期4卷 291-296页

作者： weilun wang Shiqun Li Jiashan Hu Feng Xing Guangdong Provincial Key Laboratory of Durability for Civil Engineering Shenzhen University Shenzhen China School of Materials Science and Engineering University of Jinan Jinan China

In this study, we measured the resistances (test frequency 837.8 Hz) of the paste of Portland cement (PC) and phosphoaluminate cement (PALC) subjected to different types of corrosion and different numbers of freeze-thaw cycles. This study aimed to improve understanding of the changing characteristics of paste resistance from both micro and macro perspectives by associating changes in the paste microstructure with changes in the paste mechanical strength using X-ray diffraction (XRD), nuclear magnetic resonance (NMR), and other methods. Our results showed that changes in the paste resistance under the corrosive action of ambient media could signal the deterioration of paste structure and loss of paste strength. Continuous hydration reactions within the paste were found to render it more dense and increase its resistance. Invasion of corrosive ions was found to continue to increase paste resistance if the structure of the cement paste was not destroyed. Otherwise, paste resistance would decrease. Corrosive media were found to cause the dispersion of hydrated gels with certain degree of polymerization. Because spatial resistance was found to cause difficulty in the transportation of ion clusters, the decreases in resistance caused by long-term corrosion might be reduced due to a compensation effect. This effect was found to be related to the severity of structural damage to the paste. The magnitudes of corrosive effects of chemical media on the radicals in the cement paste structure were found to occur in the following order: SiO4 > AlO4 > PO4. The resistance and strength of the PC was always lower than those of PALC. In addition, losses of resistance and strength by PALC were mainly due to deterioration of the radical structure of AlO6.

关键词： Cement Paste Ambient Media Resistance Characterization Microstructure Strength

The Pore Structure of Phosphoaluminate Cement

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Open Journal of Composite Materials 2012年第3期2卷 104-112页

作者： weilun wang Peng Liu Ming Zhang Jiashan Hu Feng Xing Guangdong Provincial Key Laboratory of Durability for Marine Civil Engineering Shenzhen University Shenzhen China School of Civil Engineering and Architecture Central South University Changsha China

The effects of curing time and water-to-cement ratio (W/C) on the pore structure of phosphoaluminate cement (PAC) paste are here presented. Based on the adsorption and condensation theory, the adsorption isotherm of hardened paste was tested using the Brunauer-Emmett-Teller (BET) nitrogen adsorption method. The phase composition and morphology of hydration products cured at different times were analyzed using X-ray diffraction (XRD), and a hydration heat test instrument (HHT) was employed to determine the heat of hydration. The effects of curing time and W/C on the pore structure of PAC are significant. The adsorption isotherm is fitted to the second category based on the Brun-auer- Deming-Deming-Teller (BDDT) classification system. Adsorption volume was found to increase with W/C and then decrease with age. The hysteresis loop of PAC is fitted to the H3 type based on International Union of Pure and Applied Chemistry (IUPAC) guidelines, and the adsorption volume and area enclosed by the hysteresis loop were found to increase with W/C and then decrease with age. BET surface and saturated adsorbed volume of PAC both increase with W/C and decrease with curing time, which is attributable to the greater hydration that produces and changes the characteristics of the pore structure.

关键词： Phosphoaluminate Cement Pore Structure Adsorption Curing Time

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自然环境中混凝土内部温度响应规律

中南大学学报（自然科学版） 2014年第2期45卷 570-575页

作者：王卫仑刘鹏邢锋深圳大学广东省滨海土木工程耐久性重点实验室广东深圳518060 中南大学土木工程学院湖南长沙410075

通过理论分析,推导出自然环境温度作用模型和混凝土内温度响应模型,同时,借助不同混凝土及不同深度的混凝土内温度试验,检证模型的合理性。研究结果表明:所建立的理论模型能够较准确地描述自然环境与混凝土内温度变化规律,计算曲线与实... 详细信息

通过理论分析,推导出自然环境温度作用模型和混凝土内温度响应模型,同时,借助不同混凝土及不同深度的混凝土内温度试验,检证模型的合理性。研究结果表明:所建立的理论模型能够较准确地描述自然环境与混凝土内温度变化规律,计算曲线与实测结果有较好的一致性;由于混凝土自身热阻效应,混凝土内温度响应与自然环境温度表现出温度响应波幅、极值和滞后时间等方面的均有差异;低水灰比的混凝土内温度响应较敏感且响应幅值衰减较小,混凝土内温度响应幅值随距表层深度增加而减小。

关键词：混凝土自然环境温度响应

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边框钢纤维混凝土剪力墙抗震性能研究

应用基础与工程科学学报 2016年第6期24卷 1279-1288页

作者：楚留声赵军王卫仑郑州大学土木工程学院河南郑州450001 深圳大学广东省滨海土木工程耐久性重点实验室广东深圳518060

针对剪力墙约束边缘构件受力复杂、施工困难的特点,提出了在剪力墙约束边缘构件中采用钢纤维局部增强的方法来改进其抗震性能,并将其命名为边框钢纤维混凝土剪力墙.结合试验结果和有限元数值模拟,研究了钢纤维体积率和剪跨比对边框钢纤... 详细信息

针对剪力墙约束边缘构件受力复杂、施工困难的特点,提出了在剪力墙约束边缘构件中采用钢纤维局部增强的方法来改进其抗震性能,并将其命名为边框钢纤维混凝土剪力墙.结合试验结果和有限元数值模拟,研究了钢纤维体积率和剪跨比对边框钢纤维混凝土剪力墙承载力、位移和延性的影响,并与整体钢纤维混凝土剪力墙相应的抗震性能进行了对比分析.结果表明,在剪力墙约束边缘构件内掺加钢纤维对于剪力墙结构的承载力和延性均具有一定的提升效果,其中位移延性最大可提升约102.8%.相对于整体钢纤维混凝土剪力墙,采用边框钢纤维混凝土剪力墙具有较大的经济优势,而且并未牺牲整体钢纤维剪力墙太大承载力和位移延性.

关键词：钢纤维混凝土约束边缘构件剪力墙抗震性能

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蒸养条件下钢渣粗骨料对混凝土的破坏作用

清华大学学报（自然科学版） 2015年第9期55卷 940-944页

作者：米贵东王强王卫仑清华大学土木系北京100084 深圳大学广东省滨海土木工程耐久性重点实验室深圳518060

为了揭示钢渣粗骨料因安定性不良问题而对混凝土造成破坏的规律,将钢渣粗骨料和含钢渣粗骨料的混凝土进行了压蒸试验,研究了钢渣粗骨料含量对不同强度的混凝土的破坏规律。所用钢渣的游离CaO和MgO质量百分数分别为4.83%和4.76%。研究结... 详细信息

为了揭示钢渣粗骨料因安定性不良问题而对混凝土造成破坏的规律,将钢渣粗骨料和含钢渣粗骨料的混凝土进行了压蒸试验,研究了钢渣粗骨料含量对不同强度的混凝土的破坏规律。所用钢渣的游离CaO和MgO质量百分数分别为4.83%和4.76%。研究结果显示:压蒸条件下,游离CaO和MgO矿物会加速反应使钢渣粗骨料发生膨胀破坏,含钢渣粗骨料的混凝土可能会因钢渣产生的内部膨胀应力而产生损伤;钢渣粗骨料占粗骨料的比例越大,对混凝土造成的损伤越严重;混凝土的强度越高,抵抗钢渣粗骨料造成内部膨胀应力的能力越强,但钢渣粗骨料的含量仍需严格控制,就该文采用的钢渣而言,钢渣粗骨料质量百分数不能超过40%。

关键词：钢渣粗骨料压蒸膨胀应力

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低可见雷达目标探测技术研究

西北工业大学学报 1999年第2期17卷 280-284页

作者：王伟伦宗凯宋小牧西北工业大学

提出了利用双基地雷达探测隐身目标的新设想，并进行了有关的实验。本研究并不依赖大双基地角造成目标ＲＣＳ增强的机理，而是基于远端传感器及扩频增益以提高防空系统对隐身目标的探测距离，并对有关接收部分进行了计算机仿真及电路实... 详细信息

提出了利用双基地雷达探测隐身目标的新设想，并进行了有关的实验。本研究并不依赖大双基地角造成目标ＲＣＳ增强的机理，而是基于远端传感器及扩频增益以提高防空系统对隐身目标的探测距离，并对有关接收部分进行了计算机仿真及电路实验。结果表明，将扩频技术引入双基地雷达，会获得明显的效益；收发之间的长基线将使有效探测距离大大向前延拓。

关键词：双基地雷达低可见雷达目标隐身目标目标探测