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俯仰跟踪任务中的驾驶员神经网络模型辨识

航空学报 2010年第9期31卷 1708-1714页

作者：谭文倩 A.V.efremov 屈香菊北京航空航天大学航空科学与工程学院北京100191 莫斯科航空学院飞行力学与控制系俄罗斯莫斯科125993

在飞机设计中,应用驾驶员数学模型预测飞机飞行品质是避免人机系统出现不良耦合的重要途径之一。为了提高飞行品质的预测精度,采用人工神经网络(NN)方法进行驾驶员模型辨识,着重研究该模型对不同飞机被控对象的适应能力。首先,详细分析... 详细信息

在飞机设计中,应用驾驶员数学模型预测飞机飞行品质是避免人机系统出现不良耦合的重要途径之一。为了提高飞行品质的预测精度,采用人工神经网络(NN)方法进行驾驶员模型辨识,着重研究该模型对不同飞机被控对象的适应能力。首先,详细分析了驾驶员完成俯仰跟踪任务的操纵行为特点,提出适用于该驾驶员行为描述的神经网络模型结构形式。然后,根据对不同被控对象进行俯仰跟踪实时仿真实验的结果,对神经网络模型参数进行识别。最后,对模型辨识结果进行了精度评价。研究结果表明,该辨识方法适用于研究具有不同增益、不同短周期振荡频率飞机被控对象的驾驶员操纵行为特性。

关键词：人机系统驾驶员模型数学模型神经网络飞行品质

A Criterion Based on Closed-loop Pilot-aircraft Systems for Predicting Flying Qualities

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Chinese Journal of Aeronautics 2010年第5期23卷 511-517页

作者：谭文倩 A.V.efremov 屈香菊北京航空航天大学航空科学与工程学院北京100083 莫斯科航空学院飞行力学与控制系俄罗斯莫斯科125993

During the process of aircraft design, the mathematical model of pilot control behavior characteristics is always used to predict aircraft flying qualities （FQ）. This is one of the important methods to avoid pilot-aircraft adverse coupling. In order to study the FQ criterion based on closed-loop pilot-aircraft systems, first, an experimental database is built, which includes 40 aircraft dynamics configurations and the corresponding flight simulation results. Second, the mathematical pilot models with a set of different aircraft configurations are obtained by this experimental database. Then, two FQ criteria, Neal-Smith criterion and Moscow Aviation Institute （MAI） criterion, are analyzed. And the relationship between the FQ level evaluated by actual pilot and the parameters of closed-loop pilot-aircraft systems is studied. Finally, an improved criterion of aircraft FQ is built based on the above two criteria. This new criterion is further used to predict FQ for four new aircraft dynamics configurations, and the prediction results verify its accuracy and practicability.

关键词： pilot-aircraft system flying qualities flight simulation pilot model Neal-Smith criterion

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一种预测驾驶员操纵行为的建模方法

北京航空航天大学学报 2010年第10期36卷 1140-1144页

作者：谭文倩 A.V.efremov 屈香菊北京航空航天大学航空科学与工程学院北京100191 莫斯科航空学院飞行力学与控制系莫斯科125993

在飞机设计中,应用驾驶员数学模型预测飞机飞行品质是避免人机系统出现不良耦合的重要途径之一.驾驶员神经网络模型是利用飞行模拟实验数据建立的驾驶员模型.基于该模型,针对纵向单通道俯仰跟踪任务,详细讨论了具有不同增益、不同短周... 详细信息

在飞机设计中,应用驾驶员数学模型预测飞机飞行品质是避免人机系统出现不良耦合的重要途径之一.驾驶员神经网络模型是利用飞行模拟实验数据建立的驾驶员模型.基于该模型,针对纵向单通道俯仰跟踪任务,详细讨论了具有不同增益、不同短周期振荡频率飞机构型的驾驶员操纵行为变化规律.研究结果表明:对于特性相似的飞机构型,其驾驶员操纵特性也相似.因此,提出了一种利用相似构型的驾驶员操纵行为特性建立驾驶员预测模型的方法.通过对预测模型进行精度评价,可以证明采用本方法能够获得比较满意的驾驶员操纵行为特性预测结果.

关键词：人机系统驾驶员模型神经网络建立模型飞行品质

Surgical treatment of femoral deformities in polyostotic fibrous dysplasia and McCune-Albright syndrome:A literature review

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World Journal of Orthopedics 2022年第3期13卷 329-338页

作者： Giulio Gorgolini Alessandro Caterini Lorenzo Nicotra Fernando De Maio Kristian efremov Pasquale Farsetti Department of Clinical Science and Translational Medicine University of Rome Tor VergataSection of Orthopaedics and TraumatologyTor Vergata HospitalRome 00133Italy

BACKGROUND Surgical correction of femoral deformities in polyostotic fibrous dysplasia(PFD)or McCune-Albright syndrome(MAS),such as coxa vara or shepherd’s crook deformity,is a *** To evaluate the treatment of patients with femoral deformities caused by PDF or MAS treated by osteotomies and stabilized with different methods,by analyzing the most relevant studies on the *** A literature search was performed in Medline database(PubMed).Articles were screened for patients affected by PFD or MAS surgically managed by osteotomies and stabilized with different *** The initial search produced 184 studies,with 15 fulfilling the eligibility criteria of our *** articles(1987-2019)included 111 patients overall(136 femurs).CONCLUSION Based on our results,the preferred method to stabilize corrective osteotomies is intramedullary nailing with neck cross *** the deformity is limited to the proximal part of the femur,a screw or blade plate may be used,although there is a high risk of fracture below the *** the femur is entirely involved,a two-stage procedure may be considered.

关键词： Polyostotic fibrous dysplasia McCune-Albright syndrome Coxa vara Shepherd’s crook deformity Femoral osteotomy Intramedullary nailing

Hydrochemical Peculiarities of Bog Ecosystems in the North-Siberian Lowland

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Journal of Water Resource and Protection 2010年第7期2卷 665-674页

作者： Tamara.efremova Stanislav efremov 不详

Surface waters of eutrophic bogs (fens) in the North-Siberian (Taimyr) lowland are characterized by hydrocarbonate, sulfate as well as hydro carbonate-sulfate calcium-magnesium composition. They relate to the type of oxygen waters, mainly, to the class of neutral weakly alkaline and to the family of ultrafresh and fresh waters and to the kind of waters poor with dissolved organic matter. Natural hydrochemical background of bog ecosystems makes in heavy metals in the first approximation: Co–0.16, Pb–0.57, Ni–4.67 and Cu–5.94 mkg/L. In most cases the surface waters are not polluted by heavy metals. Bog waters located in immediate closeness from Norilsk mining and smelting industrial complex are polluted by nickel at mid-level.

关键词： Bogs Hydrochemical Characteristics Heavy Metals Pollution

Primary Thermokarst on Agricultural Lands,Central Yakutia

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Primary Thermokarst on Agricultural Lands,Central Yakutia

Mechano-chemical selections of two competitive unfolding pathways of a single DNA i-motif

Asian Conference on Permafrost

作者： P.V.efremov Melnikov Permafrost Institute Siberian BranchRussian Academy of Sciences

The early stage of thermokarst development has been monitored in Central Yakutia since *** main monitoring site is a 157 ha unirrigated field at *** is an inter-alas area on the right bank of the Lena River which was cleared of tree vegetation and ploughed *** plots were established at the site to monitor thermokarst development,and soil temperature and *** field was abandoned in 1996 and is now used for livestock *** after clearing shallow thaw pits began to form on the field surface and along its *** the field,they used to disappear during spring and autumn *** the field margins and around the slash piles,cryogenic processes progressed.A lake 28 m long,19 m wide and 1.85 m deep formed in the northern *** troughs developed in places along the field *** 1992,little surface disturbance was observed in the *** thaw pits occurred on the ground *** borings and pits frequently encountered subsurface cavities at a depth of 0.4 to 0.6 *** changes in the cryogenic conditions occurred in *** new frost cracks,thaw pits and troughs,and collapse pits were detected and investigated throughout the *** 1994,most thaw pits were leveled by spring tillage.A small surface subsidence,4 by 5m in size and up to 0.4 m in depth,formed on plot *** continued to expand during the following years and now is a mature depression measuring 91 m in length,50 m in width and 1.71 m in maximum depth relative the field *** persists here into late June and even throughout July in a rainy summer *** gravimetric soil moisture contents in the active layer did not drop below 20-25% during the last three *** active layer depth increased to 4.5 m in the thermokarst hummock and 2.05 m in the *** temperature at 3.2 m depth warmed due to high moisture *** varied from-0.2 to 2.0℃ in the hummock and from-0.4 to-0,2℃ in the hollow over the year *** presen

关键词： Thermokarst agricultural landscape thaw depression soil moisture content active layer

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Chinese Physics B 2014年第6期23卷 621-628页

作者：徐悦陈虎璩玉杰 Artem K.efremov 黎明欧阳钟灿刘冬生严洁 State Key Laboratory of Theoretical Physics Institute of Theoretical Physics Mechanobiology Institute National University of Singapore Department of Physics National University of Singapore School of Physics University of Chinese Academy of Sciences Department of Physics Xiamen University Key Laboratory of Organic Optoelectronics & Molecular Engineering of the Ministry of Education Department of Chemistry Tsinghua University

The DNA i-motif is a quadruplex structure formed in tandem cytosine-rich sequences in slightly acidic conditions. Besides being considered as a building block of DNA nano-devices, it may also play potential roles in regulating chromo- some stability and gene transcriptions. The stability of i-motif is crucial for these functions. In this work, we investigated the mechanical stability of a single i-motif formed in the human telomeric sequence 51-（CCCTAA）3CCC, which revealed a novel pH and loading rate-dependent bimodal unfolding force distribution. Although the cause of the bimodal unfolding force species is not clear, we proposed a phenomenological model involving a direct unfolding favored at lower loading rate or higher pH value, which is subject to competition with another unfolding pathway through a mechanically stable inter- mediate state whose nature is yet to be determined. Overall, the unique mechano-chemical responses of i-motif-provide a new perspective to its stability, which may be useful to guide designing new i-motif-based DNA mechanical nano-devices.

关键词： single-molecule techniques i-motif folding/structure of biomolecules mechanical proper-ties/biomolecules

Composite Materials for Adsorption-Catalytic Purification of Toxic Organic Impurities

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Journal of Energy and Power Engineering 2015年第3期9卷 259-264页

作者： Kusman Dossumov Mikhail Nauryzbayev Dina Churina Sergey efremov Bulat Kenessov Moldir Telbayeva Center of Physical-Chemical Methods of Investigations and Analysis al-Farabi Kazakh National University Almaty 050012Kazakhstan

Design of high effective catalysts with unique properties opens good perspectives for solving environmental problems of cleaning waste gas, particularly from toxic impurities of organic solvents. A new thermostable nanostructured composite materials based on shungyte was obtained and determined their adsorption capacity on the model substance o-xylene. Xylene used as a model substance is a part of the organic solvent presents in waste industrial gases. Best xylene sorbents （449.7 mg/g）--activated shungyte containing 70% carbon and saksaul charcoal （554.3 mg/g）. Then polyoxide catalysts on the base of transition metals （Ni, Mn, Cu） modified by the rare earth elements （La, Ce and Nd）, supported on a granular carrier were studied in the reaction of deep oxidation of o-xylene. 100% activity showed 7.0% Cu-Mn-Ce-catalyst at T： 250-300℃, Cxylene： 0.6 g/ms, the optimum space velocity of gas--1,200 h^1 for catalysts supported on a granular carrier. The results obtained can be used in the purification of waste gas from paint, furniture, cable, printing and other enterprises from the impurities of toxic organic solvents.

关键词： Composite material adsorption xylene catalyst sorbent shungyte.

Block Matrix Representation of a Graph Manifold Linking Matrix Using Continued Fractions

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Applied Mathematics 2014年第13期5卷 1894-1902页

作者： Fernando I. Becerra López Vladimir N. efremov Alfonso M. Hernandez Magdaleno Mathematics Department CUCEI University of Guadalajara Guadalajara Mexico

We consider the block matrices and 3-dimensional graph manifolds associated with a special type of tree graphs. We demonstrate that the linking matrices of these graph manifolds coincide with the reduced matrices obtained from the Laplacian block matrices by means of Gauss partial diagonalization procedure described explicitly by W. Neumann. The linking matrix is an important topological invariant of a graph manifold which is possible to interpret as a matrix of coupling constants of gauge interaction in Kaluza-Klein approach, where 3-dimensional graph manifold plays the role of internal space in topological 7-dimensional BF theory. The Gauss-Neumann method gives us a simple algorithm to calculate the linking matrices of graph manifolds and thus the coupling constants matrices.

关键词： Graph Manifolds Continued Fractions Laplacian Matrices Kaluza-Klein