68,507 research outputs found
Recursive Identification of Hammerstein Systems with application to Electrically Stimulated Muscle
No full textTwo methods for recursive identification of Hammerstein systems are considered. In the first method, the recursive least squares algorithm is applied to an overparameterized representation of the Hammerstein model and a rank-1 approximation is used to recover the linear and nonlinear parameters from the estimated overparameterized form. In the second method, the linear and nonlinear parameters are recursively estimated in an alternate manner. The superiority of the second method is confirmed using a numerical simulation example, together with experimentally measured data from electrically stimulated muscles
Identification of Electrically Stimulated Muscle after Stroke
No full textThe design of controllers to enable the application of Functional Electrical Stimulation as part of a rehabilitation programme for stroke patients requires an accurate model of electrically stimulated muscle. In this paper, nonlinear dynamics of the electrically stimulated muscle under isometric conditions is investigated, leading to the requirement to identify a Hammerstein model structure. Here we develop a two-stage identification method based on a preliminary construction of the linear part that is used as an initial estimate. Then the two-stage method is applied to identify the nonlinear part and optimize the linear part. The separable least squares optimization algorithm and traditional ramp deconvolution method are implemented here and compared with the proposed method using a simulated muscle system that is based on experimental data from stroke patients. The results show that the proposed method outperforms two other previously proposed methods when implemented on the simulated muscle system with different noise levels
Gerta S. Freeman Collection 1915-1999
No full textThe collection contains Questionnaire I + II of the Austrian Heritage Collection at the Leo Baeck Institute. Also included are photocopies of various documents pertaining to Gerta Spiegel Freeman and her family in Vienna, Austria, such as education certificates, emigration documents, photographs, and others. Typescripts include Gerta Freeman’s autobiographical manuscript after her arrival in the United States in May 1938, and the transcript of an interview with her brother Harry Spiegel.Gerta Freeman née Spiegel was born 1915 in Vienna, Austria. 1921 to 1926 she attended elementary school in the Ninth District, then moving on to "Reform Realgymnasium" in the Eighth District. She became an English Teacher in 1934/35. During her studies she was a member of the social democratic youth movement, particularly the socialist group "Rote Falken". Her brothers were politically active in the socialist organization ’Republikanischer Schutzbund’. Gerta left Vienna in April of 1938 for Switzerland and France (Paris). In May 1938 she took the ship "Britannic" from Le Havre to the USA, where she worked as a sales manager.A videotape documenting Harry Spiegel’s activities in the Spanish Civil War and the Resistance in France during Nazi-German occupation has been removed to the LBI AV Collection.Inventory in fileAustrian Heritage CollectionSee also AHC interview with Gerta Freeman (AHC 1243)digitize
AHC interview with Gerta S. Freeman
No full textGerta Freeman (nee Spiegel) was born in Vienna in 1915. She attended elementary school in the ninth Viennese district from 1921-26. Then she went to "Reform Realgymnasium" in the eighth district. She became an English Teacher in 1934/35. She was a member of the "Roten Falken", s socialist group, and of social demokratic youth movement. Her brothers were politically active active in 'Schutzbund'. She left Vienna in April of 1938 for Switzerland, France (Paris). She took the ship "Britannic" from Le Havre to the USA in May 1938. She works in the USA as a sales manager.1 videocassette has been removed to the A/V collection.Austrian Heritage CollectionSee also Gerta S. Freeman Collection (AR 11035
System Identification of Muscle Dynamics for ILC-based Stroke Rehabilitation
No full textIn this paper results are presented for the identification of electrically stimulated muscle dynamics in stroke patients. This research forms a critical component in the model-based control of electrically stimulated upper-limb movement, which, in turn, is necessary to maximise improvement in sensory-motor function during rehabilitation with electrical stimulation. An overview is firstly provided of an experimental test facility that has been developed for stroke rehabilitation. During treatment stroke participants use this system to track elliptical trajectories projected onto a target above their arm, assisted by electrical stimulation applied to their triceps. The control approach used to apply stimulation is summarised, and the structure of the muscle model within the scheme is described. A novel iterative identification scheme is then introduced for the muscle dynamics of stroke patients, and experimental results are presented to confirm its performance and suitability in the proposed rehabilitation context
L. G. Freeman et J. Gonzalez Echegaray - La grotte d'Altamira. La Maison des Roches
No full textLe Roux Charles Tanguy. L. G. Freeman et J. Gonzalez Echegaray - La grotte d'Altamira. La Maison des Roches. In: Revue archéologique de l'ouest, tome 18, 2001. pp. 246-247
Note sur le huitain XLVI du Testament de Villon.
No full textFreeman M.J. Note sur le huitain XLVI du Testament de Villon.. In: Romania, tome 107 n°425, 1986. pp. 103-113
Le métier de géographe, par T. W. Freeman
No full textPinchemel Philippe. Le métier de géographe, par T. W. Freeman. In: Annales de Géographie, t. 78, n°426, 1969. pp. 210-212
Identification of the Dynamics of Human Arms after Stroke
No full textThe design of controllers to enable the application of Functional Electrical Stimulation as part of a rehabilitation programme for stroke patients requires an accurate model of electrically stimulated muscle. In this paper, nonlinear dynamics of the electrically stimulated muscle under isometric conditions is investigated, leading to the requirement to identify a Hammerstein model structure. Here we develop a two-stage identification method based on a preliminary construction of the linear part that is used as an initial estimate. Then the two-stage method is applied to identify the nonlinear part and optimize the linear part. The traditional ramp deconvolution method are implemented here and compared with the proposed method using a simulated muscle system that is based on experimental data from stroke patients. The results show that the proposed method outperforms the other one when implemented on the simulated muscle system with different noise levels
Presentation by Ms. Connie Freeman, Regional Director for Eastern and Southern Africa, Canada's International Development Research Centre (IDRC) : 2002 National Policy Research Conference, Ottawa (ON), Oct. 24, 2002
No full textFrench version available in IDRC Digital Library: Communication de Mme Connie Freeman, Directrice régionale pour l'Afrique orientale et australe, Centre de recherches pour le développement international (CRDI) : Conférence nationale de la recherche sur les politiques 2002, Ottawa (Ontario), 24 oct. 200
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