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用于频率域航电数据调平的区域控制法
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作者 郭涛 孔祥礼 王子栋 《物探与化探》 CAS CSCD 2013年第2期255-259,共5页
消除航空电磁数据中的条带状误差最通用的方法是结合手工调平和以窗口滤波为主要手段的计算机自动调平技术。为解决窗口参数的选取问题,提出了区域控制法。该方法首先利用2D-DDNL(data dpendent nonlinear)滤波器原理将整个网格化的航... 消除航空电磁数据中的条带状误差最通用的方法是结合手工调平和以窗口滤波为主要手段的计算机自动调平技术。为解决窗口参数的选取问题,提出了区域控制法。该方法首先利用2D-DDNL(data dpendent nonlinear)滤波器原理将整个网格化的航电数据矩阵作为一个窗口,得到整个区域的背景值,作为总区域背景场控制点值,用其对这个区域进行小窗口2D-DDNL滤波得到的局部背景值进行调节,即自动改变窗口参数,使局部背景场适应总区域背景场控制点值;这样得到的背景场与原始场相减,便得到一个包含局部地质异常和条带误差的中间量;对这个中间量采用一维改进的中值滤波,分离出条带误差,进而得到最终调平结果。该方法能自动调节窗口参数大小,减少了人为干扰,自动化程度高,较好地保留了有用地质信息,为航电数据调平提供了一种新方法。 展开更多
关键词 航空电磁 区域控制法 条带状误差 数据调平
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大跨度悬索桥施工期主缆索股线形区域分段控制法 被引量:6
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作者 王达 张永健 +1 位作者 杨琴 刘扬 《长安大学学报(自然科学版)》 EI CAS CSCD 北大核心 2015年第5期57-64,共8页
为实现对复杂温度环境下索股线形的精准控制,提出了基于悬索桥构造特点及地形特征的区域分段控制法,推导了索股垂度与长度、垂度与跨径、垂度与温度之间的关系表达式;可快速测定主缆索股温度场,计算出边、中跨的索股调整系数,继而确定... 为实现对复杂温度环境下索股线形的精准控制,提出了基于悬索桥构造特点及地形特征的区域分段控制法,推导了索股垂度与长度、垂度与跨径、垂度与温度之间的关系表达式;可快速测定主缆索股温度场,计算出边、中跨的索股调整系数,继而确定索股调整量,实现索股线形的有效控制。研究结果表明:悬索桥施工过程中,主缆索股温度具有明显的时变性及随机性;根据控制精度要求及主缆索股材质特性,提出了等效温度法,从而提高了工作效率;边跨索股的调整系数具有较强的非线性特征,并随边跨索股垂度的变化而改变,而中跨的索股调整系数施工前后变化不大;结合桥位附近的地表地形,对主缆索股温度进行区域分段控制是合理可行的,提出的区域分段控制法效率高、精度好,且具有较强适用性。 展开更多
关键词 桥梁工程 区域分段控制 温度 主缆索股 调整系数
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Optimal Boundary Control Method for Domain Decomposition Algorithm
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作者 闫桂峰 冯恩民 《Journal of Beijing Institute of Technology》 EI CAS 2000年第2期113-119,共7页
To study the domain decomposition algorithms for the equations of elliptic type, the method of optimal boundary control was used to advance a new procedure for domain decomposition algorithms and regularization method... To study the domain decomposition algorithms for the equations of elliptic type, the method of optimal boundary control was used to advance a new procedure for domain decomposition algorithms and regularization method to deal with the ill posedness of the control problem. The determination of the value of the solution of the partial differential equation on the interface——the key of the domain decomposition algorithms——was transformed into a boundary control problem and the ill posedness of the control problem was overcome by regularization. The convergence of the regularizing control solution was proven and the equations which characterize the optimal control were given therefore the value of the unknown solution on the interface of the domain would be obtained by solving a series of coupling equations. Using the boundary control method the domain decomposion algorithm can be carried out. 展开更多
关键词 domain decomposition methods(DDM) boundary control REGULARIZATION coupling equations
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Control of combustion area using electrical resistivity method for underground coal gasification 被引量:12
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作者 Selivanova Tatiana Grebenyuk Igor Belov Alexey 《International Journal of Mining Science and Technology》 SCIE EI 2012年第3期351-355,共5页
Underground coal gasification (UCG) is one of the clean technologies to collect heat energy and gases (hydrogen, methane, etc.) in an underground coal seam. It is necessary to further developing environ- mentally ... Underground coal gasification (UCG) is one of the clean technologies to collect heat energy and gases (hydrogen, methane, etc.) in an underground coal seam. It is necessary to further developing environ- mentally friendly UCG system construction. One of the most important UCG's problems is underground control of combustion area for efficient gas production, estimation of subsidence and gas leakage to the surface. For this objective, laboratory experiments were conducted according to the UCG model to iden- ti[y the process of combustion cavity development by monitoring the electrical resistivity activity on the coal samples to setup fundamental data for the technology engineering to evaluate combustion area. While burning coal specimens, that had been sampled from various coal deposits, electrical resistivity was monitored. Symmetric four electrodes system (ABMN) of direct and low-frequency current electric resistance method was used for laboratory resistivity measurement of rock samples. Made research and the results suggest that front-end of electro conductivity activity during heating and combusting of coal specimen depended on heating temperature. Combusting coal electro conductivity has compli- cated multistage type of change. Electrical resistivity method is expected to be a useful geophysical tool to for evaluation of combustion volume and its migration in the coal seam. 展开更多
关键词 Underground coal gasificationMonitoringElectro conductivityLaboratory experimentCoal specimen
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Model predictive control synthesis algorithm based on polytopic terminal region for Hammerstein-Wiener nonlinear systems 被引量:2
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作者 李妍 陈雪原 毛志忠 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第9期2028-2034,共7页
An improved model predictive control algorithm is proposed for Hammerstein-Wiener nonlinear systems.The proposed synthesis algorithm contains two parts:offline design the polytopic invariant sets,and online solve the ... An improved model predictive control algorithm is proposed for Hammerstein-Wiener nonlinear systems.The proposed synthesis algorithm contains two parts:offline design the polytopic invariant sets,and online solve the min-max optimization problem.The polytopic invariant set is adopted to replace the traditional ellipsoid invariant set.And the parameter-correlation nonlinear control law is designed to replace the traditional linear control law.Consequently,the terminal region is enlarged and the control effect is improved.Simulation and experiment are used to verify the validity of the wind tunnel flow field control algorithm. 展开更多
关键词 Hammerstein-Wiener nonlinear systems model predictive control polytopic terminal constraint set parameter-correlation nonlinear control stability linear matrix inequalities (LMIs)
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