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Morphologically controlled synthesis of MgFe-LDH using MgO and succinic acid for enhanced arsenic adsorption:Kinetics,equilibrium,and mechanism studies 被引量:1
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作者 Yusuf Olalekan Zubair Shigeshi Fuchida +1 位作者 Keishi Oyama Chiharu Tokoro 《Journal of Environmental Sciences》 2025年第2期637-649,共13页
In this study,we investigated improving the performance of a layered double hydroxide(LDH)for the adsorption of As(III)and As(V)by controlling the morphology of LDH crystals.The LDH was synthesized via a simple coprec... In this study,we investigated improving the performance of a layered double hydroxide(LDH)for the adsorption of As(III)and As(V)by controlling the morphology of LDH crystals.The LDH was synthesized via a simple coprecipitation method using barely soluble MgO as a precursor and succinic acid(SA)as a morphological control agent.Doping the LDH crystals with carboxylate ions(RCOO−)derived from SA caused the crystals to develop in a radial direction.This changed the pore characteristics and increased the density of active surface sites.Subsequently,SA/MgFe-LDH showed excellent affinity for As(III)and As(V)with maximum sorption densities of 2.42 and 1.60 mmol/g,respectively.By comparison,the pristine MgFe-LDH had sorption capacities of 1.56 and 1.31 mmol/g for As(III)and As(V),respectively.The LDH was effective over a wide pH range for As(III)adsorption(pH 3-8.5)and As(V)adsorption(pH 3-6.5).Using a combination of spectroscopy and sorption modeling calculations,the main sorption mechanism of As(III)and As(V)on SA/MgFe-LDH was identified as inner-sphere complexation via ligand exchangewith hydroxyl group(-OH)and RCOO−.Specifically,bidentate As-Fe complexeswere proposed for both As(III)and As(V)uptake,with the magnitude of formation varying with the initial As concentration.Importantly,the As-laden adsorbent had satisfactory stability in simulated real landfill leachate.These findings demonstrate that SA/MgFe-LDH exhibits considerable potential for remediation of As-contaminated water. 展开更多
关键词 ARSENIC Heavy magnesium oxide Succinic acid Layered double hydroxide Adsorption Bidentate complex STABILIZATION
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Spatial Patterns and Controlling Factors of Soil Organic Carbon and Total Nitrogen in the Three River Headwaters Region,China 被引量:1
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作者 CUI Qiao LI Zongxing +2 位作者 FENG Qi ZHANG Baijuan ZHAO Yue 《Chinese Geographical Science》 2025年第1期131-148,共18页
The alpine ecosystem has great potential for carbon sequestration.Soil organic carbon(SOC)and total nitrogen(TN)are highly sensitive to climate change,and their dynamics are crucial to revealing the effect of climate ... The alpine ecosystem has great potential for carbon sequestration.Soil organic carbon(SOC)and total nitrogen(TN)are highly sensitive to climate change,and their dynamics are crucial to revealing the effect of climate change on the structure,function,and services of the ecosystem.However,the spatial distribution and controlling factors of SOC and TN across various soil layers and vegetation types within this unique ecosystem remain inadequately understood.In this study,256 soil samples in 89 sites were collected from the Three River Headwaters Region(TRHR)in China to investigate SOC and TN and to explore the primary factors affecting their distribution,including soil,vegetation,climate,and geography factors.The results show that SOC and TN contents in 0-20,20-40,40-60,and 60-80 cm soil layers are 24.40,18.03,14.04,12.40 g/kg and 2.46,1.90,1.51,1.17 g/kg,respectively;with higher concentrations observed in the southeastern region compared to the northwest of the TRHR.One-way analysis of variance reveals that SOC and TN levels are elevated in the alpine meadow and the alpine shrub relative to the alpine steppe in the 0-60 cm soil layers.The structural equation model explores that soil water content is the main controlling factor affecting the variation of SOC and TN.Moreover,the geography,climate,and vegetation factors notably indirectly affect SOC and TN through soil factors.Therefore,it can effectively improve soil water and nutrient conditions through vegetation restoration,soil improvement,and grazing management,and the change of SOC and TN can be fully understood by establishing monitoring networks to better protect soil carbon and nitrogen. 展开更多
关键词 controlling factors different soil layers soil organic carbon(SOC) soil total nitrogen(TN) alpine ecosystem the Three River Headwaters Region(TRHR) China
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Challenges and suggestions for high-speed boundary layer transition control using surface microstructure
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作者 Jisen YUAN Shenghao YU Zhansen QIAN 《Chinese Journal of Aeronautics》 2025年第4期7-9,共3页
Due to the coexistence of compressibility,viscosity,and threedimensional effects,laminar flow is difficult to maintain for high-speed boundary layer on complex geometries.The unstable disturbance waves in the boundary... Due to the coexistence of compressibility,viscosity,and threedimensional effects,laminar flow is difficult to maintain for high-speed boundary layer on complex geometries.The unstable disturbance waves in the boundary layer are excited and rapidly increase during the receptivity process,so sufficiently large Reynolds stress causes the basic flow velocity profile to change,and the formation of turbulence is inevitable. 展开更多
关键词 high speed boundary layer large reynolds stress transition control surface microstructure unstable disturbance waves CHALLENGES suggestions boundary layer
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Controlled proximal contractions with an application to a class of integral equations
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作者 Mudasir Younis Haroon Ahmad 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第3期645-665,共21页
In this study,we explore some of the best proximity point results for generalized proximal contractions in the setting of double-controlled metric-type spaces.A non-trivial example is given to elucidate our analysis,a... In this study,we explore some of the best proximity point results for generalized proximal contractions in the setting of double-controlled metric-type spaces.A non-trivial example is given to elucidate our analysis,and some novel results are derived.The discovered results generalize previously known results in the context of a double controlled metric type space environment.This article’s proximity point results are the first of their kind in the realm of controlled metric spaces.To build on the results achieved in this article,we present an application demonstrating the usability of the given results. 展开更多
关键词 integral equation double controlled metric type space proximal contractive mappings coincidence best proximity point
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Multi-layer controlled remote implementation of partially unknown single-qudit operations
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作者 Siyi Li Songya Ma Si Jin 《Communications in Theoretical Physics》 2025年第2期52-63,共12页
Our concern is to investigate controlled remote implementation of partially unknown operations with multiple layers.We first propose a scheme to realize the remote implementation of singlequbit operations belonging to... Our concern is to investigate controlled remote implementation of partially unknown operations with multiple layers.We first propose a scheme to realize the remote implementation of singlequbit operations belonging to the restricted sets.Then,the proposed scheme is extended to the case of single-qudit operations.As long as the controller and the higher-layer senders consent,the receiver can restore the desired state remotely operated by the sender.It is worth mentioning that the recovery operation is deduced by general formulas which clearly reveal the relationship with the measurement outcomes.For the sake of clarity,two specific examples with two levels are given respectively.In addition,we discuss the influence of amplitude-damping noise and utilize weak measurement and measurement reversal to effectively resist noise. 展开更多
关键词 controlled remote implementation of quantum operation multiple layers recovery operation amplitude-damping noise weak measurement and measurement reversal
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Experimental and numerical study on double wedge shock/shock interaction controlled by a single-pulse plasma synthetic jet
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作者 Wei XIE Zhenbing LUO +3 位作者 Yan ZHOU Qiang LIU Xiong DENG Yinxin ZHU 《Plasma Science and Technology》 2025年第4期30-41,共12页
The phenomenon of shock/shock interaction(SSI)is widely observed in high-speed flow,and the double wedge SSI represents one of the typical problems encountered.The control effect of single-pulse plasma synthetic jet(P... The phenomenon of shock/shock interaction(SSI)is widely observed in high-speed flow,and the double wedge SSI represents one of the typical problems encountered.The control effect of single-pulse plasma synthetic jet(PSJ)on double wedge type-Ⅵand type-ⅤSSI was investigated experimentally and numerically,and the influence of discharge energy was also explored.The findings indicate that the interaction between PSJ and the high-speed freestream results in the formation of a plasma layer and a jet shock,which collectively governs the control of SSI.The control mechanism of single-pulse PSJ on SSI lies in its capacity to attenuate both shock and SSI.For type-ⅥSSI,the original second-wedge oblique shock is eliminated under the control of PSJ,resulting in a new type-ⅥSSI formed by the jet shock and the first-wedge oblique shock.For type-ⅤSSI,the presence of PSJ effectively mitigates the intensity of Mach stem,supersonic jet,and reflected shocks,thereby facilitating its transition into type-ⅥSSI.The numerical results indicate that the peak pressure can be reduced by approximately 32.26%at maximum.Furthermore,the development of PSJ also extends in the Z direction.The pressure decreases in the area affected by both PSJ and jet shock due to the attenuation of the SSI zone.With increasing discharge energy,the control effect of PSJ on SSI is gradually enhanced. 展开更多
关键词 plasma synthetic jet shock/shock interaction double wedge high-speed vehicle active flow control(Some figures may appear in colour only in the online journal)
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Precise Control of the Recollision Dynamics in Nonsequential Double Ionization by Spatially Inhomogeneous Few-Cycle Negatively Chirped Laser Pulses
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作者 Yingbin Li Fengrun Wu +10 位作者 Fanfei Liu Shuaijie Kang Zhengfa Li Ke Zhang Yifan Liu Kuo Li Chunyang Zhai Jingkun Xu Pu Wang Qiming Zhao Benhai Yu 《Chinese Physics Letters》 2025年第5期26-32,共7页
With a three-dimensional semiclassical ensemble method, we theoretically investigated the nonsequential double ionization of Ar driven by the spatially inhomogeneous few-cycle negatively chirped laser pulses. Our resu... With a three-dimensional semiclassical ensemble method, we theoretically investigated the nonsequential double ionization of Ar driven by the spatially inhomogeneous few-cycle negatively chirped laser pulses. Our results show that the recollision time window can be precisely controlled within an isolated time interval of several hundred attoseconds, which is useful for understanding the subcycle correlated electron dynamics. More interestingly, the correlated electron momentum distribution (CEMD) exhibits a strong dependence on laser intensity. That is, at lower laser intensity, CEMD is located in the first quadrant. As the laser intensity increases,CEMD shifts almost completely to the second and fourth quadrants, and then gradually to the third quadrant.The underlying physics governing the CEMD's dependence on laser intensity is explained. 展开更多
关键词 recollision time window recollision dynamics correlated electron momentum distribution nonsequential double ionization precise control understanding subcycle correlated electron dynamics three dimensional semiclassical ensemble method spatially inhomogeneous few cycle negatively chirped laser pulses
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考虑双界面滑移的三层组合梁非线性有限元分析
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作者 邓继华 盛希凯 +2 位作者 彭建新 王磊 邵旭东 《土木工程学报》 北大核心 2026年第1期61-75,共15页
以三层组合梁为研究对象,开展考虑双界面滑移的几何非线性有限元分析方法的研究。首先,基于三层组合梁的弹性力学基本方程,即平衡、几何以及物理方程,建立其位移控制微分方程,利用直接刚度法推导出局部坐标系(共旋坐标系)下具有“精确... 以三层组合梁为研究对象,开展考虑双界面滑移的几何非线性有限元分析方法的研究。首先,基于三层组合梁的弹性力学基本方程,即平衡、几何以及物理方程,建立其位移控制微分方程,利用直接刚度法推导出局部坐标系(共旋坐标系)下具有“精确”特点的几何线性单元刚度矩阵,其中离散的柔性抗剪连接件用连续界面黏结滑移模型模拟;其次,利用几何非线性分析的共旋坐标法导出结构坐标系与局部坐标系(共旋坐标系)之间的转换矩阵,建立结构坐标系下三层组合梁单元的几何非线性切线刚度矩阵,对应的等效节点力矩阵可同时求得;最后,针对实际工程中施加于三层组合梁的集中力作用点以及边界约束点与有限元模型节点不一致而导致的偏心效应,该文采用刚臂以及力等效的原则予以考虑。综合上述成果建立三层组合梁考虑双界面滑移的几何非线性有限元分析方法,研制出相应程序,对三个典型三层组合梁算例进行分析,与已有文献计算及试验结果的对比验证该文方法及程序的正确性与可靠性。 展开更多
关键词 三层组合梁 几何非线性 双界面滑移 共旋坐标法 精确单元刚度矩阵
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MACa_(0.5)Ge_(0.5)I_(3)/MACa_(0.125)Ge_(0.875)I_(3)同质结钙钛矿太阳电池的数值分析
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作者 甘永进 郭杨炎 +1 位作者 周玉婷 陈多瑜 《电源技术》 北大核心 2026年第1期160-169,共10页
基于一维太阳电池数值仿真软件SCAPS,提出了结构为SnO_(2)/MACa_(0.5)Ge_(0.5)I_(3)/MACa_(0.125)Ge_(0.875)I_(3)/Cu_(2)O的双活性层同质结器件结构。通过控制变量法研究了钙钛矿层厚度和缺陷态密度、金属背电极功函数和温度对电池性... 基于一维太阳电池数值仿真软件SCAPS,提出了结构为SnO_(2)/MACa_(0.5)Ge_(0.5)I_(3)/MACa_(0.125)Ge_(0.875)I_(3)/Cu_(2)O的双活性层同质结器件结构。通过控制变量法研究了钙钛矿层厚度和缺陷态密度、金属背电极功函数和温度对电池性能的影响。仿真结果表明:钙钛矿层厚度的增加促使开路电压和填充因子减小,而短路电流密度逐渐增加。相比于MACa_(0.5)Ge_(0.5)I_(3)层,MACa_(0.125)Ge_(0.875)I_(3)厚度的变化对开路电压影响更为明显;电池性能随着钙钛矿层缺陷态密度的增加不断恶化,相比于MACa_(0.5)Ge_(0.5)I_(3)层,MACa_(0.125)Ge_(0.875)I_(3)层缺陷态密度的变化对开路电压影响更明显;金属背电极功函数的增加促进器件内建电场增强,从而促进开路电压提升;温度的升高促使器件复合率升高,使器件内耗增大,从而抑制电池输出高性能。 展开更多
关键词 SCAPS 双活性层 缺陷态密度 功函数 温度
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基于同步中转的双高箱办理站装卸设备集成调度优化
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作者 张辉 蒋惠园 卢升荣 《铁道学报》 北大核心 2026年第1期18-30,共13页
为提升双高箱办理站内的装卸、转运作业效率,面向多装卸线作业场景,针对中转集装箱的站内转运提出同步中转作业模式。考虑作业序列、轨道吊安全距离等约束条件,定义集装箱离站作业优先级以动态分配卸载集装箱的堆场箱位,以最小化装卸作... 为提升双高箱办理站内的装卸、转运作业效率,面向多装卸线作业场景,针对中转集装箱的站内转运提出同步中转作业模式。考虑作业序列、轨道吊安全距离等约束条件,定义集装箱离站作业优先级以动态分配卸载集装箱的堆场箱位,以最小化装卸作业完工用时和新增堆场翻箱操作用时为优化目标,构建基于同步中转作业模式的轨道吊、集卡、空箱堆高机集成调度优化模型。基于头脑风暴优化算法和大规模邻域搜索算法设计混合算法求解模型,并通过实例验证模型及算法的有效性。结果表明,混合算法具备较强的全局搜索能力,随着算例规模增大表现更为显著。基于时空区间的轨道吊干涉判断方法与考虑等待、避让操作的轨道吊柔性调度策略有效,平均扩大7.19%的可行设备集成调度方案范围。同步中转作业模式相较于混合装卸、先卸后装作业模式能够减少设备作业和集卡往返次数,平均减少19.31%、58.36%的装卸作业完工用时,避免中转箱的无效堆存,同时最小化堆场新增翻箱操作数,实现办理站全局作业效率提升。 展开更多
关键词 双高箱办理站 中转集装箱 同步中转 轨道吊柔性调度策略 装卸设备集成调度
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Active Vibration Control of Beam Using Electro-magnetic Constrained Layer Damping 被引量:3
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作者 牛红攀 张亚红 +1 位作者 张希农 谢石林 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第2期115-124,共10页
This paper investigates vibration control of beam through electro-magnetic constrained layer damping (EMCLD) which consists of electromagnet layer, permanent magnet layer and viscoelastic damping layer. When the coi... This paper investigates vibration control of beam through electro-magnetic constrained layer damping (EMCLD) which consists of electromagnet layer, permanent magnet layer and viscoelastic damping layer. When the coil of the electromagnet is electrified with proper control strategy, the electromagnet can exert magnetic force opposite to the direction of structural deformation so that the structural vibration is attenuated. A mathematical model is developed based on the equivalent current method to calculate the electromagnetic control force produced by EMCLD. The governing equations of the system are obtained using Hamilton's Principle and then reduced with the assumed-mode method. A simulation on vibration control of a cantilever beam is conducted under the velocity proportional feedback to demonstrate the energy dissipation capability of EMCLD, and the beam system with the same parameter is experimented. The results of experiment and simulation are compared and the results show that the EMCLD is an effective means for suppressing modal vibration. The results also indicate that the beam system has better control performance for larger control current. The EMCLD method presented in this paper provides an applicable and efficient tool for the vibration control of structures. 展开更多
关键词 electro-magnetic constrained layer damping (EMCLD) vibration control active control
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Effect of process parameters on microstructure and properties of AM50A magnesium alloy parts formed by double control forming 被引量:4
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作者 姜巨福 王迎 曲建俊 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第2期321-333,共13页
Effects of process parameters on microstructure and mechanical properties of the AM50A magnesium alloy components formed by double control forming (DCF) were investigated via a four-factor and four-level orthogonal ... Effects of process parameters on microstructure and mechanical properties of the AM50A magnesium alloy components formed by double control forming (DCF) were investigated via a four-factor and four-level orthogonal experiment. The variable curves of DCF showed that the forging procedure was started in the following 35 ms after the injection procedure was completed. It was confirmed that the high-speed filling and high-pressure densifying were combined together in the DCF process. Better surface quality and higher mechanical properties were achieved in the components formed by DCF as compared to die casting (DC) due to the refined and uniform microstructure with a few defects or without defects. Injection speed affected more effectively the yield strength (YS), ultimate tensile strength (UTS) and elongation as compared to pouring temperature, die temperature and forging force. But the pouring temperature had a more significant effect on hardness as compared to injection speed, die temperature and forging force. Pouring temperature of 675 &#176;C, injection speed of 2.7 m/s and forging force of 4000 kN except for die temperature were the optimal parameters for obtaining the highest YS, UTS, elongation and Vickers hardness. Die temperatures of 205, 195, 195 and 225 &#176;C were involved in achieving the highest YS, UTS, elongation and Vickers hardness, respectively. Obvious microporosity and microcracks were found on the fracture surface of the components formed by DC, deteriorating the mechanical properties. However, the tensile fracture morphology of the components formed by DCF was characterized by ductile fracture due to a large number of dimples and no defects, which was beneficial for improving the mechanical properties. 展开更多
关键词 AM50A magnesium alloy double control forming mechanical properties microstructure
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泡沫铜负载MgCoFe-LDO激活过一硫酸盐降解磺胺甲噁唑
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作者 冯茜 商克峰 +2 位作者 鲁娜 姜楠 李杰 《大连理工大学学报》 北大核心 2026年第1期10-17,共8页
层状双氧化物(LDO)可以激活过一硫酸盐(PMS),产生大量活性物种,高效降解水中的各类有机微污染物.然而,金属氧化物类催化剂在催化反应过程中存在金属离子浸出、难回收的问题,影响其实际应用.采用水热法合成了镁钴铁层状双氧化物并将其负... 层状双氧化物(LDO)可以激活过一硫酸盐(PMS),产生大量活性物种,高效降解水中的各类有机微污染物.然而,金属氧化物类催化剂在催化反应过程中存在金属离子浸出、难回收的问题,影响其实际应用.采用水热法合成了镁钴铁层状双氧化物并将其负载于泡沫铜上(MgCoFe-LDO@f-Cu),用于激活PMS降解磺胺甲噁唑(SMX).实验结果表明:当负载MgCoFe-LDO的泡沫铜规格为80目,煅烧温度为300℃,煅烧时间为3h时,催化剂激活PMS降解SMX的效果较好.当MgCoFe-LDO@f-Cu投加量为10g/L,PMS初始浓度为1mmol/L,初始pH值为7时,20mg/LSMX在20min内的降解率可达96.04%;5次重复使用后,MgCoFe-LDO@f-Cu/PMS体系对SMX的降解率仍可达83.87%.离子浸出量测定实验表明,与MgCoFe-LDO相比,MgCoFe-LDO@f-Cu中总镁、总钴和总铁的浸出率分别下降了41.50%、28.84%和30.81%,说明MgCoFe-LDO@f-Cu催化剂化学性质更为稳定,且便于回收. 展开更多
关键词 层状双氧化物 过一硫酸盐 磺胺甲噁唑 催化氧化
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EFFECTIVE DOUBLE LOOP CONTROL FOR A SQUARE WAVE BRUSHLESS DC MOTOR
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作者 周波 李先祥 朱震莲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期34+30-33,共5页
A new type of brushless DC motor has been developed by using a square wave rare earth permanent magnet synchronous motor with its double loop control circuit. The double loop control scheme of the drive system yie... A new type of brushless DC motor has been developed by using a square wave rare earth permanent magnet synchronous motor with its double loop control circuit. The double loop control scheme of the drive system yields a combination of desired characteristics including simplified control structure, small ripple torque, high speed accuracy, wide operating speed range, and fast dynamic response. Experimental results confirm excellent characteristics of the motor. 展开更多
关键词 synchronous motors speed control systems INVERTERS brushless DC motor double loop control square wave motors
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Effect of Continuous Application of Controlled Release Nitrogen Fertilizer in Various Types of Soil in Dong-Ting Lake Region under Double Rice Cropping System
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作者 鲁艳红 廖育林 +3 位作者 聂军 谢坚 杨曾平 戴平安 《Agricultural Science & Technology》 CAS 2012年第2期351-356,379,共7页
[Objective] This study aimed to explore the effects of continuous application of controlled release nitrogen fertilizer under double rice cropping system. [Method] By modeling three types of paddy soils in Dong-Ting L... [Objective] This study aimed to explore the effects of continuous application of controlled release nitrogen fertilizer under double rice cropping system. [Method] By modeling three types of paddy soils in Dong-Ting Lake area, four treatments as no fertilizer (CK), urea, controlled release nitrogen fertilizer (CRNF) and 70% controlled release nitrogen fertilizer (70% CRNF) were designed in the micro-plot trials from 2005 to 2008. [Result] The rice yield in treatment CRNF at N 150 kg/hm2 was increased by 10.3%, 8.0% and 2.4% compared with treatment of urea, in alluvial sandy loamy paddy soil (ALS), purple calcareous clayey paddy soil (PCS), and reddish yellow loamy paddy soil (RYS), respectively; and the yield in treatment of 70% CRNF was increased by 6.1%, 2.6% and -0.8%, respectively. The ranking order of nitrogen uptake amount by plant in early rice and late rice was CRNF 70% CRNF urea CK in all three types of soil. Nitrogen utilization efficiency of CRNF in above three types of soil was 60.7%, 59.6% and 56.3%, increased by 23.8%, 19.4% and 16.3% compared with that in treatment of urea, respectively. Nitrogen utilization efficiency of CRNF in early rice was increased year by year, and was higher than that of 70% CRNF during the whole experiment stage, while that in late rice was increased first and then decreased from the 3rd year. [Conclusion] Continuous application CRNF could alleviate the decreasing of soil nitrogen fertility and organic carbon especially in ALS, increase rice yield and nitrogen utilization efficiency in double-rice cropping system. 展开更多
关键词 Double cropping rice controlled release nitrogen fertilizer Continuous fertilization YIELD Fertilizer use efficiency Soil fertility
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抑制风水系统输出振荡的附加协同-滑模控制设计
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作者 曾丕江 何常胜 +1 位作者 曾云 王芳芳 《排灌机械工程学报》 北大核心 2026年第1期40-47,共8页
为抑制风电功率波动对系统内其他机组的影响,针对风水互补系统,以水电机组为核心控制对象,旨在通过融合协同控制与滑模控制理论,实现风水电机组的联合调控.首先,选取水电机组机械功率、角速度及风电机组有功功率构成宏观变量,并定义了... 为抑制风电功率波动对系统内其他机组的影响,针对风水互补系统,以水电机组为核心控制对象,旨在通过融合协同控制与滑模控制理论,实现风水电机组的联合调控.首先,选取水电机组机械功率、角速度及风电机组有功功率构成宏观变量,并定义了附加控制器的联合控制信号.在此基础上,设计了基于协同控制的滑模面,提出了一种协同-滑模附加控制器的设计方法.该方法保留原系统原有PID控制器,将风电机组与水电机组的状态变量引入控制器设计,并导出控制律.将该控制律以附加反馈的形式引入功角控制微分方程中,实现系统模型的改进与机组协同控制.仿真结果表明,当风电机组功率正弦变化时水电机组的输出振荡幅度由±0.10降至±0.02,而联合系统输出的有功功率、无功功率及角速度的振荡减小至原来的1/2左右.所提方法能有效抑制输出振荡,提高风水互补系统的输出稳定性. 展开更多
关键词 风水系统 附加控制器 滑模控制 协同控制 一管双机
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ControlLogix控制系统在电厂的应用 被引量:1
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作者 唐文军 田力 +1 位作者 邓广龙 李乃川 《自动化技术与应用》 2006年第6期76-77,共2页
针对电厂自动化改造的工艺和技术要求,设计以ControlLogix罗克韦尔自动化为主netlink三层网络的现场总线控制。实现对电厂的线路改造以增加电力输送能力,并完成新上30MW机组项目的辅助车间控制。
关键词 三层网络 controlLOGIX5000 自动控制
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小样本不平衡数据集异常双层窗口检测方法研究
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作者 方叶彤 张伦传 《现代电子技术》 北大核心 2026年第1期137-140,共4页
当数据库的正例样本与负例样本之间存在数量级差别时,不平衡数据中存在的类重叠问题会使数据的决策边界重叠。使用单一窗口更关注数据的相似性结构而不是时间尺度的分层,导致在检测不同时间尺度的数据时几何平均值(G-mean)数值较小。为... 当数据库的正例样本与负例样本之间存在数量级差别时,不平衡数据中存在的类重叠问题会使数据的决策边界重叠。使用单一窗口更关注数据的相似性结构而不是时间尺度的分层,导致在检测不同时间尺度的数据时几何平均值(G-mean)数值较小。为此,文中提出一种小样本不平衡数据集异常双层窗口检测方法。采用改进合成少数类样本过采样技术,新建不重复少数类样本,实现小样本不平衡数据集均衡化处理;考虑数据的时间尺度,采用双层窗口将均衡化后的时序数据划分为多个子时间序列,计算斜率置信区间距离半径特征,识别异常子序列,结合K-means聚类算法从异常子序列中识别出异常数据。实验结果显示:该方法可有效实现不平衡数据集均衡化处理,精准完成不同不平衡率小样本数据集的异常数据检测,G-mean数值高于0.7,为异常数据检测提供了一种有效的解决方案。 展开更多
关键词 小样本 不平衡数据集 异常检测 双层窗口 过采样 时间序列 聚类算法 均衡化
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水库连通工程取水口水力特性研究
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作者 叶焰中 林勇华 +2 位作者 后小霞 渠立光 韩松林 《长江科学院院报》 北大核心 2026年第1期210-217,共8页
水库连通工程取水口因水位变幅大、水流双向、运行方式受管道糙率影响导致取水口水力特性复杂。以公明—清林径水库连通工程为研究对象,采用水力学计算与物理模型试验方法对双向输水取水口和分层控流取水口的水力特性开展研究。研究结... 水库连通工程取水口因水位变幅大、水流双向、运行方式受管道糙率影响导致取水口水力特性复杂。以公明—清林径水库连通工程为研究对象,采用水力学计算与物理模型试验方法对双向输水取水口和分层控流取水口的水力特性开展研究。研究结果表明:(1)糙率增大,工程输水能力降低、洞线水头损失增大,影响进水口的水流衔接方式与输水调度方案。(2)双向输水取水口在进流时流速较小,无不良流态产生,出流时出流顺畅;流道沿程压力分布正常。(3)分层控流取水口在闸门控泄时闸后自由射流冲击消能井壁,水流在下游隧洞平面转弯处产生封洞水跃,提出了可行的工程与运行调度措施加以避免。(4)水库连通工程运行条件复杂,工程运行后应根据监测资料反演主线隧洞的实际糙率,调整水力控制方式。研究成果可为类似调水工程取水口的设计和调度运行提供参考。 展开更多
关键词 双向输水取水口 分层控流取水口 叠梁门 糙率 水力特性 封洞水跃
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Multiscale Theoretical Calculations Empower Robust Electric Double Layer Toward Highly Reversible Zinc Anode
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作者 Yufan Xia Zhen Luo +6 位作者 Shuang Chen Yang Xiang Gao Weng Hongge Pan Ben Bin Xu Mi Yan Yinzhu Jiang 《Nano-Micro Letters》 2026年第3期406-427,共22页
The electric double layer(EDL)at the electrochemical interface is crucial for ion transport,charge transfer,and surface reactions in aqueous rechargeable zinc batteries(ARZBs).However,Zn anodes routinely encounter per... The electric double layer(EDL)at the electrochemical interface is crucial for ion transport,charge transfer,and surface reactions in aqueous rechargeable zinc batteries(ARZBs).However,Zn anodes routinely encounter persistent dendrite growth and parasitic reactions,driven by the inhomogeneous charge distribution and water-dominated environment within the EDL.Compounding this,classical EDL theory,rooted in meanfield approximations,further fails to resolve molecular-scale interfacial dynamics under battery-operating conditions,limiting mechanistic insights.Herein,we established a multiscale theoretical calculation framework from single molecular characteristics to interfacial ion distribution,revealing the EDL’s structure and interactions between different ions and molecules,which helps us understand the parasitic processes in depth.Simulations demonstrate that water dipole and sulfate ion adsorption at the inner Helmholtz plane drives severe hydrogen evolution and by-product formation.Guided by these insights,we engineered a“water-poor and anion-expelled”EDL using 4,1’,6’-trichlorogalactosucrose(TGS)as an electrolyte additive.As a result,Zn||Zn symmetric cells with TGS exhibited stable cycling for over 4700 h under a current density of 1 mA cm^(−2),while NaV_(3)O_(8)·1.5H_(2)O-based full cells kept 90.4%of the initial specific capacity after 800 cycles at 5 A g^(−1).This work highlights the power of multiscale theoretical frameworks to unravel EDL complexities and guide high-performance ARZB design through integrated theory-experiment approaches. 展开更多
关键词 Zn anode Theoretical calculations Electric double layers Aqueous rechargeable zinc batteries
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