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A two-level hierarchical discrete-device control method for power networks with integrated wind farms 预览
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作者 Fengda XU Qinglai GUO +2 位作者 Hongbin SUN Boming ZHANG Lin JIA 《现代电力系统与清洁能源学报(英文)》 CSCD 2019年第1期88-98,共11页
Power systems depend on discrete devices, such as shunt capacitors/reactors and on-load tap changers, for their long-term reliability.In transmission systems that contain large wind farms, we must take into account th... Power systems depend on discrete devices, such as shunt capacitors/reactors and on-load tap changers, for their long-term reliability.In transmission systems that contain large wind farms, we must take into account the uncertainties in wind power generation when deciding when to operate these devices.In this paper, we describe a method to schedule the operation of these devices over the course of the following day.These schedules are designed to minimize wind-power generation curtailment, bus voltage violations, and dynamic reactive-power deviations,even under the worst possible conditions.Daily voltagecontrol decisions are initiated every 15 min using a dynamic optimization algorithm that predicts the state of the system over the next 4-hour period.For this, forecasts updated in real-time are employed, because they are more precise than forecasts for the day ahead.Day-ahead schedules are calculated using a two-stage robust mixedinteger optimization algorithm.The proposed control strategies were tested on a Chinese power network with wind power sources;the control performance was also validated numerically. 展开更多
关键词 Automatic voltage CONTROL Model PREDICTIVE CONTROL On-load tap CHANGER SHUNT capacitor/reactor TWO-STAGE robust optimization Wind-power integration
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带约束的自适应抗差整体最小二乘滤波
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作者 白征东 李帅 +1 位作者 陈波波 黎奇 《测绘科学》 CSCD 北大核心 2019年第1期5-9,15共6页
针对目前新型的高铁轨道变形监测实施过程中出现的各种复杂问题,该文提出并推导了带约束的自适应抗差整体最小二乘滤波算法,以旋转矩阵的各个元素作为状态参数,将旋转矩阵的单位正交性作为参数的约束条件,位置解算精度比卡尔曼滤波提高... 针对目前新型的高铁轨道变形监测实施过程中出现的各种复杂问题,该文提出并推导了带约束的自适应抗差整体最小二乘滤波算法,以旋转矩阵的各个元素作为状态参数,将旋转矩阵的单位正交性作为参数的约束条件,位置解算精度比卡尔曼滤波提高了约29%。实验表明,此算法比传统方法更适用于高铁轨道变形监测这一应用场景。同时,此算法可以应用到任何需要考虑观测方程中的粗差和系数矩阵中的随机误差、动态模型的偏差且状态参数有任意约束的情形,包括其他测量、定位与导航场景。 展开更多
关键词 高铁轨道 变形监测 自适应滤波 抗差 整体最小二乘
安全数据采集代理顽健部署策略研究 预览
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作者 陈黎丽 王震 +3 位作者 郭云川 华佳烽 姚宇超 李凤华 《通信学报》 EI CSCD 北大核心 2019年第6期51-65,共15页
随着“网络黑产”事件频繁发生,攻击者以“趋利”的思想来策略地发动针对性的攻击。现有网络监测系统缺少针对“策略式攻击”精准有效的监测策略。因此,在敌对环境中,如何优化部署采集代理获取更好的监测效果成为一个极为重要的课题。... 随着“网络黑产”事件频繁发生,攻击者以“趋利”的思想来策略地发动针对性的攻击。现有网络监测系统缺少针对“策略式攻击”精准有效的监测策略。因此,在敌对环境中,如何优化部署采集代理获取更好的监测效果成为一个极为重要的课题。针对该问题,提出了一种顽健采集代理部署策略。首先,引入攻防博弈思想,对采集代理和威胁事件及其之间的关系进行度量,构建度量攻防博弈模型MADG模型;然后,考虑传统精确求解算法无法求解该问题,利用目标函数的次模和非增的性质设计了顽健采集代理部署算法RCD算法进行近似求解;最后,对RCD算法进行了验证。实验结果表明,所提模型和方法是可行有效的,且具有可扩展性。 展开更多
关键词 采集代理 安全数据 攻防博弈 顽健性 优化部署
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复合材料支撑机翼撑杆位置与结构综合优化设计 预览
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作者 肖志鹏 仇翯辰 周磊 《工程力学》 EI CSCD 北大核心 2019年第9期213-220,共8页
针对复合材料支撑机翼,发展了一种撑杆位置和结构综合优化设计的方法。在两种严重设计载荷状态下,考虑气动弹性效应和复合材料铺层结构的不确定性,以结构质量最小化为目标,以翼尖垂直变形、翼尖扭角、撑杆屈曲稳定性、颤振速度和强度要... 针对复合材料支撑机翼,发展了一种撑杆位置和结构综合优化设计的方法。在两种严重设计载荷状态下,考虑气动弹性效应和复合材料铺层结构的不确定性,以结构质量最小化为目标,以翼尖垂直变形、翼尖扭角、撑杆屈曲稳定性、颤振速度和强度要求为约束,在一个优化过程中实现了撑杆位置和结构参数的同步优化设计和鲁棒优化设计。结果表明,翼尖垂直变形和颤振速度要求对于撑杆位置影响明显,最优的撑杆展向位置都靠近翼根一侧,同时撑杆的总体稳定性成为同步优化设计的关键约束。鲁棒优化设计得到的撑杆位置和结构参数的最优组合对铺层结构的不确定性摄动具有良好的抗干扰性,鲁棒优化得到的最优撑杆位置会随着设计变量摄动范围而变化,翼尖垂直变形成为鲁棒优化设计的关键约束。 展开更多
关键词 支撑机翼 复合材料 综合优化 鲁棒 气动弹性 撑杆位置 颤振
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稳健选权迭代算法在姿态测量中的应用
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作者 何红丽 左益宏 李宏 《控制工程》 CSCD 北大核心 2019年第6期1183-1186,共4页
随着雷达天线阵面的减小,雷达阵面与飞机基准安装面准确安装难度变大。针对机载雷达小天线阵面安装姿态测量问题,给出了完整的测量方案,构建了测量系统;针对含有粗差的测量数据,在抗差估计的理论基础上,提出了具有稳健初值的选权迭代法... 随着雷达天线阵面的减小,雷达阵面与飞机基准安装面准确安装难度变大。针对机载雷达小天线阵面安装姿态测量问题,给出了完整的测量方案,构建了测量系统;针对含有粗差的测量数据,在抗差估计的理论基础上,提出了具有稳健初值的选权迭代法,进行了算法精度验证,处理结果令人满意,已成功应用到机载雷达天线阵面位姿测量中,也可推广应用在其他武器系统安装标定任务中。 展开更多
关键词 天线阵面 姿态 选权迭代法 稳健
Robust topology optimization of hinge-free compliant mechanisms with material uncertainties based on a non-probabilistic field model
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作者 Junjie ZHAN Yangjun LUO 《机械工程前沿:英文版》 CSCD 2019年第2期201-212,共12页
This paper presents a new robust topology optimization framework for hinge-free compliant mechanisms with spatially varying material uncertainties,which are described using a non-probabilistic bounded field model.Boun... This paper presents a new robust topology optimization framework for hinge-free compliant mechanisms with spatially varying material uncertainties,which are described using a non-probabilistic bounded field model.Bounded field uncertainties are efficiently represented by a reduced set of uncertain-but-bouncled coeflficients on the basis of the series expansion method.Robust topology optimization of compliant mechanisms is then defined to minimize the variation in output displacement under constraints of the mean displacement and predefined material volume.The nest optimization problem is solved using a gradient-based optimization algorithm.Numerical examples are presented to illustrate the effectiveness of the proposed method for circumventing hinges in topology optimization of compliant mechanisms. 展开更多
关键词 compliant mechanisms ROBUST topology optimization HINGES uncertainty BOUNDED field
Adaptive Robust Control for a Lower Limbs Rehabilitation Robot Running Under Passive Training Mode 预览
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作者 Xiaolong Chen Han Zhao +1 位作者 Shengchao Zhen Hao Sun 《自动化学报:英文版》 CSCD 2019年第2期493-502,共10页
This paper focuses on the problem of the adaptive robust control of a lower limbs rehabilitation robot(LLRR) that is a nonlinear system running under passive training mode. In reality, uncertainties including modeling... This paper focuses on the problem of the adaptive robust control of a lower limbs rehabilitation robot(LLRR) that is a nonlinear system running under passive training mode. In reality, uncertainties including modeling error, initial condition deviation, friction force and other unknown external disturbances always exist in a LLRR system. So, it is necessary to consider the uncertainties in the unilateral man-machine dynamical model of the LLRR we described. In the dynamical model, uncertainties are(possibly fast) time-varying and bounded. However, the bounds are unknown. Based on the dynamical model, we design an adaptive robust control with an adaptive law that is leakagetype based and on the framework of Udwadia-Kalaba theory to compensate for the uncertainties and to realize tracking control of the LLRR. Furthermore, the effectiveness of designed control is shown with numerical simulations. 展开更多
关键词 Adaptive robust control LOWER LIMBS REHABILITATION ROBOT mechanical system PASSIVE training UNCERTAINTIES
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Weedy Rice Evolution:De-domestication or Semi-domestication?
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作者 Xiao Yang 《分子植物:英文版》 SCIE CAS CSCD 2019年第5期613-614,共2页
Weeds,especially close relatives of crops,pose severe threats to agricultural production worldwide.As an evolutionary"evil twin"of cultivated rice,weedy rice(Oryza sativa f.spontanea)has emerged as a pernici... Weeds,especially close relatives of crops,pose severe threats to agricultural production worldwide.As an evolutionary"evil twin"of cultivated rice,weedy rice(Oryza sativa f.spontanea)has emerged as a pernicious weed that evolved with strong growth and reproductive advantages,such as easy seed shattering and long seed dormancy,strong competitiveness for depriving resources,and robust environmental adaptability,to outcompete cultivated rice in the paddy field(Figure 1). 展开更多
关键词 Weedy Rice EVOLUTION WEEDS ROBUST ENVIRONMENTAL
Zeolitic Imidazolate Framework 8-Derived Au@ZnO for Efficient and Robust Photocatalytic Degradation of Tetracycline
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作者 Bijun Gao Jin Zhou +7 位作者 Hongliang Wang Guping Zhang Jinghui He Qingfeng Xu Najun Li Dongyun Chen Hua Li Jianmei Lu 《中国化学:英文版》 SCIE CAS CSCD 2019年第2期148-154,共7页
Summary of main observation and conclusion Tetracycline (TC) and other antibiotics accumulated in groundwater and soil pollute ecological environment and threaten human health. Gold nan oparticles doped on photocataly... Summary of main observation and conclusion Tetracycline (TC) and other antibiotics accumulated in groundwater and soil pollute ecological environment and threaten human health. Gold nan oparticles doped on photocatalysts are able to enhance the photodegradation efficiency during removing these antibiotics, but preparation of Au nanoparticles of well-dispersion on photocatalysts remains challenging. In this work, zeolite imidazolate (ZIF-8) was employed as the precursor to prepare Au@ZnO photocatalyst via impregnation and in-situ reduction method to efficiently degrade the tetracycline in the aqueous solution. Au nanoparticles are of 10 nm in size and uniformly dispersed on the surfaces of ZnO microstructures. The as-prepared Au@ZnO is able to remove 85.5% of TC of 0.010 mg/mL within 2h, presenting higher photocatalytic activity than pure ZnO catalyst. Most importantly, the catalyst shows its superior stability after five cycles without structure and activity changing. The mechanism of the photocatalytic degradation was discussed in detail. 展开更多
关键词 EFFICIENT ROBUST PHOTOCATALYTIC Degradation TETRACYCLINE
利用卷积神经网络的显著性区域预测方法 预览 被引量:1
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作者 李荣 《重庆邮电大学学报:自然科学版》 CSCD 北大核心 2019年第1期37-43,共7页
针对神经网络的显著性区域预测存在数据采集代价大、处理繁琐等问题,提出2种卷积神经网络,即从头开始训练的浅层卷积神经网络,以及前三层源自另一个网络的深层卷积神经网络。其中,浅层网络结构简单,可避免过拟合问题;深层网络可以充分... 针对神经网络的显著性区域预测存在数据采集代价大、处理繁琐等问题,提出2种卷积神经网络,即从头开始训练的浅层卷积神经网络,以及前三层源自另一个网络的深层卷积神经网络。其中,浅层网络结构简单,可避免过拟合问题;深层网络可以充分利用最底层的模型参数,收敛更快,效果更好。所提卷积神经网络应用于回归问题,均没有直接训练特征图的线性模型,而是在迁移层上训练了一堆新的卷积层。从端到端的角度解决显著性预测,将学习过程演化为损失函数的最小化问题。测试和训练在SALICON,SUN和MIT300数据集上进行,实验结果验证了所提方法的有效性。其中,深层网络和浅层网络在SALICON和SUN数据上的结果相似,深层网络在MIT300上的结果更优,与其他方法相比,所提方法具有不错的表现,而且具有跨数据集的鲁棒性。 展开更多
关键词 显著性区域预测 卷积神经网络 损失函数 显著度图 鲁棒性
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考虑缓冲时间成本的鲁棒性停机位分配 预览
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作者 冯霞 王青召 《北京理工大学学报》 EI CAS CSCD 北大核心 2019年第4期384-390,共7页
针对实际航班提前或延误给停机位分配带来的扰动问题,分析了航班实际到离港时间偏离计划时间的分布规律,提出了基于缓冲时间成本的停机位分配鲁棒性评价函数.在此基础上,建立了以缓冲时间成本、机位-航班大小差异度和远机位数等最小为... 针对实际航班提前或延误给停机位分配带来的扰动问题,分析了航班实际到离港时间偏离计划时间的分布规律,提出了基于缓冲时间成本的停机位分配鲁棒性评价函数.在此基础上,建立了以缓冲时间成本、机位-航班大小差异度和远机位数等最小为优化目标的鲁棒性停机位分配模型,设计了求解模型的禁忌搜索算法.基于首都国际机场两个典型的A、B工作日实际运行数据的模型验证结果表明,所提方法与不考虑鲁棒性及传统最小化空闲时间离差平方和的停机位分配相比,在A日航班冲突分别减少了98.1%和97.6%,在B日航班冲突分别减少了74.3%和70.8%,有效地提高了停机位分配计划的鲁棒性。 展开更多
关键词 停机位分配 禁忌搜索算法 缓冲时间成本 推出-滑入冲突 鲁棒性
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A Robust Blade Design Method based on Non-Intrusive Polynomial Chaos Considering Profile Error
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作者 GAO Limin MA Chi CAI Yutong 《热科学学报:英文版》 SCIE EI CAS CSCD 2019年第5期875-885,共11页
To weaken the influence of profile error on compressor aerodynamic performance, especially on pressure ratio and efficiency, a robust design method considering profile error is built to improve the robustness of aerod... To weaken the influence of profile error on compressor aerodynamic performance, especially on pressure ratio and efficiency, a robust design method considering profile error is built to improve the robustness of aerodynamic performance of the blade. The characteristics of profile error are random and small-scaled, which means that to evaluate the influence of profile error on blade aerodynamic performance is a time-intensive and high-precision work. For this reason, non-intrusive polynomial chaos(NIPC) and Kriging surrogate model are introduced in this robust design method to improve the efficiency of uncertainty quantification(UQ) and ensure the evaluate accuracy. The profile error satisfies the Gaussian distribution, and NIPC is carried out to do uncertainty quantification since it has advantages in prediction accuracy and efficiency to get statistical behavior of random profile error. In the integrand points of NIPC, several surrogate models are established based on Latin hypercube sampling(LHS)+ Kriging, which further reduces the costs of optimization design by replacing calling computational fluid dynamic(CFD) repeatedly. The results show that this robust design method can significantly improve the performance robustness in shorter time(40 times faster) without losing accuracy, which is meaningful in engineering application to reduce manufacturing cost in the premise of ensuring the aerodynamic performance. Mechanism analysis of the robustness improvement samples carried out in current work can help find out the key parameter dominating the robustness under the disturbance of profile error, which is meaningful to further improvement of compressor robustness. 展开更多
关键词 ROBUST design non-intrusive POLYNOMIAL CHAOS aerodynamic performance RANDOM profile ERROR UNCERTAINTY quantification
Data-Driven Global Robust Optimal Output Regulation of Uncertain Partially Linear Systems 预览
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作者 Adedapo Odekunle Weinan Gao Yebin Wang 《自动化学报:英文版》 CSCD 2019年第5期1108-1115,共8页
In this paper, a data-driven control approach is developed by reinforcement learning (RL) to solve the global robust optimal output regulation problem (GROORP) of partially linear systems with both static uncertaintie... In this paper, a data-driven control approach is developed by reinforcement learning (RL) to solve the global robust optimal output regulation problem (GROORP) of partially linear systems with both static uncertainties and nonlinear dynamic uncertainties. By developing a proper feedforward controller, the GROORP is converted into a global robust optimal stabilization problem. A robust optimal feedback controller is designed which is able to stabilize the system in the presence of dynamic uncertainties. The closed-loop system is ensured to be input-to-output stable regarding the static uncertainty as the external input. This robust optimal controller is numerically approximated via RL. Nonlinear small-gain theory is applied to show the input-to-output stability for the closed-loop system and thus solves the original GROORP. Simulation results validates the efficacy of the proposed methodology. 展开更多
关键词 ROBUST control output regulation REINFORCEMENT learning small-gain theory
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Robust Fractional-Order Proportional-Integral Observer for Synchronization of Chaotic Fractional-Order Systems 预览
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作者 Ibrahima N’Doye Khaled Nabil Salama Taous-Meriem Laleg-Kirati 《自动化学报:英文版》 CSCD 2019年第1期268-277,共10页
In this paper, we propose a robust fractional-order proportional-integral(FOPI) observer for the synchronization of nonlinear fractional-order chaotic systems. The convergence of the observer is proved, and sufficient... In this paper, we propose a robust fractional-order proportional-integral(FOPI) observer for the synchronization of nonlinear fractional-order chaotic systems. The convergence of the observer is proved, and sufficient conditions are derived in terms of linear matrix inequalities(LMIs) approach by using an indirect Lyapunov method. The proposed FOPI observer is robust against Lipschitz additive nonlinear uncertainty. It is also compared to the fractional-order proportional(FOP) observer and its performance is illustrated through simulations done on the fractional-order chaotic Lorenz system. 展开更多
关键词 Chaos SYNCHRONIZATION FRACTIONAL-ORDER CHAOTIC systems indirect Lyapunov approach linear matrix inequality(LMI) ROBUST proportional-integral OBSERVER design
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基于多源数据融合的电网抗差状态估计 预览
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作者 沈玉兰 张璞 +2 位作者 李翔宇 陈艳波 郎燕生 《广东电力》 2019年第9期146-153,共8页
现有状态估计方法的局限性主要体现在仅基于一种量测量,因而估计精度不够高,抗差性能不够好,为此,提出基于多源数据融合的电网抗差状态估计方法。对于无时标量测,根据量测数据之间的相关系数对齐时间断面,从而确定基准量测时刻。然后针... 现有状态估计方法的局限性主要体现在仅基于一种量测量,因而估计精度不够高,抗差性能不够好,为此,提出基于多源数据融合的电网抗差状态估计方法。对于无时标量测,根据量测数据之间的相关系数对齐时间断面,从而确定基准量测时刻。然后针对其中一种数据源更新速度慢以及根据不同时间段系统变化不同的情况,分别采用外推或内插法生成伪量测,在提高伪量测精度的同时提高计算效率;在采用内插法生成伪量测前,通过深度信念网络预测下一时间断面的量测结果,提高预测精度。最后提出基于最小二乘和绝对值的抗差状态估计。仿真算例证明所提抗差估计方法具有很好的收敛性和抗差性,具有良好的工程应用价值。 展开更多
关键词 数据融合 深度信念网络 伪量测 抗差 状态估计
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多元稳健估计抗差性分析 预览
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作者 韩子斌 张永彬 +1 位作者 贾敏 徐航航 《华北理工大学学报:自然科学版》 CAS 2019年第2期7-12,共6页
介绍了鲁棒估计的原理,并在实例中使用MATLAB进行编程和比较,比较最小二乘法和鲁棒估计法得到的结果。结果显示:在多元数据变化趋于平稳(各个变量间之差不超过20%)并存在粗差的情况下,稳健估计能准确地剔除粗差,使回归方程更加准确,并... 介绍了鲁棒估计的原理,并在实例中使用MATLAB进行编程和比较,比较最小二乘法和鲁棒估计法得到的结果。结果显示:在多元数据变化趋于平稳(各个变量间之差不超过20%)并存在粗差的情况下,稳健估计能准确地剔除粗差,使回归方程更加准确,并获得更加准确的预测方程。而多元数据变化幅度比较大(各个变量间之差大于20%)时,稳健估计方法得到的结果与最小二乘方法基本一致。 展开更多
关键词 最小二乘 稳健估计 粗差探测 方法比较 MATLAB
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Robust delay-dependent stability of uncertain inertied neural networks with impulsive effects and distributed-delay
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作者 Tianhu Yu Shengqiang Liu +1 位作者 Huamin Wang Yingjia Cui 《生物数学学报:英文版》 2019年第1期233-253,共21页
The robust stability problem of uncertain inertial neural networks with impulsive effects and distributed-delay is considered in the present paper.The average impulsive interval and differential inequality for delay d... The robust stability problem of uncertain inertial neural networks with impulsive effects and distributed-delay is considered in the present paper.The average impulsive interval and differential inequality for delay differential equations are used to obtain the global exponential stability of the inertial neural networks.The robust distributed-delaydependent stability criteria here are proposed in terms of both linear matrix inequalities and algebraic inequalities.Our results can not only be used to obtain the stability of the uncertain inertial neural network with impulsive disturbance,but also be utilized to design the impulsive control for the uncertain inertial neural networks.The novel criteria complement and extend the previous works on uncertain inertial neural network with/without impulsive effects.Typical numerical examples are used to test the validity of the developed stability criteria finally. 展开更多
关键词 ROBUST EXPONENTIAL stability INERTIAL neural networks distributed-delay IMPULSIVE effects
Applied statistical functions and multivariate analysis of geochemical compositional data to evaluate mineralization in Glojeh polymetallic deposit,NW Iran
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作者 F DARABI-GOLESTAN A HEZARKHANI 《地球科学前沿:英文版》 SCIE CAS CSCD 2019年第1期229-246,共18页
Various genesis of epithermal veins as well as host rock cause complication in the modeling process. Thus LINEST and controlling function were applied to improve the accuracy and the quality of the model.The LINEST is... Various genesis of epithermal veins as well as host rock cause complication in the modeling process. Thus LINEST and controlling function were applied to improve the accuracy and the quality of the model.The LINEST is a model which is based on multiple linear regression and refers to a branch of applied statistics.This method concerns directly to the application oft-test (TINV and TDIST to analyses of variables in the model)and F- test (FDIST,F-statistic to compare different models) analysis.Backward elimination technique is applied to reduce the number of variables in the model through all the borehole data.After 18 steps,an optimized reduced model (ORM)was constructed and ranked in order of importance as Pb >Ag >P >Hg>Mn>Nb >U>Sr>Sn>As > Cu,with the lowest confidence level (CL)of 92% for Cu.According to the epigenetic vein genesis of Glojeh polymetallic deposit,determination of spatial pattems and elemental associations accompanied by anomaly separation were conducted by K-means cluster and robust factor analysis method based on centered log-ratio (clr)transformed data.Therefore,12 samples (cluster 2)with the maximum distance from centroid,indicates the intensity of vein polymetallic mineralization in the deposit.In addition, an ORM for vein population was extracted for Sb >A1 > As >Mg >Pb >Cu >Ag elements with the R2 up to 0.99. On the other hand,after 23 steps of optimization process at the host rock population,an ORM Was conducted by Ag >Te >Hg >Pb >Mg >A1 >Sb >As represented in descending order oft-values.It revealed that Te and Hg can be considered as pathfinder elements for Au at the host rock.Based on the ORMs at each population Ag,Pb,and As were often associated with Au mineralization.The concentration ratio of (tSb × tA1)vein/(tSb × tA1)baekground as an enrichment index can intensify the mineralization detection.Finally,Glojeh deposit was evaluated to be classified as a vein-style Au (Ag,Pb,As)-polymetallic mineralization. 展开更多
关键词 LINEST and controlling function optimized reduced model log-ratio (clr)transformation K-means cluster robust factor analysis PATHFINDER elements veinstyle Glojeh POLYMETALLIC MINERALIZATION
基于鲁棒扰动观测器的弃风供暖系统 预览
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作者 刘前卫 《中国电力》 CSCD 北大核心 2019年第8期120-125,共6页
针对大范围弃风和全球变暖等问题,考虑风力发电的不确定性,提出了一种基于鲁棒扰动观测器的风机供电系统控制策略。首先针对风机供电系统进行建模并利用基于泰勒级数展开的扰动观测器消弭系统中存在的参数不确定和未知风力发电波动。其... 针对大范围弃风和全球变暖等问题,考虑风力发电的不确定性,提出了一种基于鲁棒扰动观测器的风机供电系统控制策略。首先针对风机供电系统进行建模并利用基于泰勒级数展开的扰动观测器消弭系统中存在的参数不确定和未知风力发电波动。其次应用了基于PLC和WinCC的分布式电锅炉供暖控制方法。最后通过仿真验证了所提方法的有效性。 展开更多
关键词 风力发电 扰动观测器 参数不确定 电锅炉供暖控制 鲁棒性
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What is the relationship between frailty and orthostatic hypotension in older adults? 预览
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作者 Suleyman Emre Kocyigit Pinar Soysal +3 位作者 Esra Ates Bulut Ali Ekrem Aydin Ozge Dokuzlar Ahmet Turan Isik 《老年心脏病学杂志:英文版》 SCIE CAS CSCD 2019年第3期272-279,共8页
Background Frailty and orthostatic hypotension (OH),which is common in older adults,is associated with morbidity and mortality.The relationship between them remains unclear.The aim of the study is to determine whether... Background Frailty and orthostatic hypotension (OH),which is common in older adults,is associated with morbidity and mortality.The relationship between them remains unclear.The aim of the study is to determine whether there is a relationship between frailty and OH.Methods A total of 496 patients who were admitted to the geriatric clinic and underwent comprehensive geriatric assessment were retrospectively reviewed.In a cross-sectional and observational study,OH was measured by the Head-up Tilt Table test at 1,3,and 5 min (respectively,OH1,OH3,and OH5) and the frailty was measured by the Fried’s frailty scale.Results The mean age of all patients was 75.4 ± 7.38.The prevalence of females was 69.8%.When the frail people were compared with the pre-frail and the robust ones,the frailty was associated with OH1.There was no relationship between the groups in terms of OH1 when the pre-frail group was compared with the robust group.OH3 were higher in the frail group than in the pre-frail group (P < 0.05) and the OH5 were higher in the frail group than in the pre-frail and robust group (P < 0.05),but OH3 and OH5 were not associated with frailty status when they were adjusted for age (P > 0.05).Slowness and weakness were associated with OH1 (P < 0.05),whereas the other components of the Fried’s test were not.Conclusions Frailty may be a risk factor for OH1.The 1^st min measurements of OH should be routinely evaluated in frail older adults to prevent OH-related poor outcomes. 展开更多
关键词 FRAIL ORTHOSTATIC HYPOTENSION Pre-frail Robust
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