FEATURES OF sEMG BASED ON SOURCE SEPARATION AND FRACTAL PROPERTIES TO DETECT WRIST MOVEMENTS

2010 ◽  
Vol 22 (04) ◽  
pp. 293-300 ◽  
Author(s):  
Sridhar P. Arjunan ◽  
Dinesh K. Kumar ◽  
Ganesh R. Naik
Keyword(s):  
Muscle Activity ◽  
Source Separation ◽  
The Elderly ◽  
Human Computer Interface ◽  
Wrist Flexion ◽  
Accurate Identification ◽  
Fractal Properties ◽  
Finger Flexion ◽  
Interface Devices

Classification of surface electromyogram (sEMG) for identification of hand and finger flexions has a number of applications such as sEMG-based controllers for near elbow amputees and human-computer interface devices for the elderly. However, the classification of an sEMG becomes difficult when the level of muscle contraction is low and when there are multiple active muscles. The presence of noise and crosstalk from closely located and simultaneously active muscles is exaggerated when muscles are weakly active such as during sustained wrist and finger flexion and of people with neuropathological disorders or who are amputees. This paper reports analysis of fractal length and fractal dimension of two channels to obtain accurate identification of hand and finger flexion. An alternate technique, which consists of source separation of an sEMG to obtain individual muscle activity to identify the finger and hand flexion actions, is also reported. The results show that both the fractal features and muscle activity obtained using modified independent component analysis of an sEMG from the forearm can accurately identify a set of finger and wrist flexion-based actions even when the muscle activity is very weak.

FRACTAL PROPERTIES OF SURFACE ELECTROMYOGRAM FOR CLASSIFICATION OF LOW-LEVEL HAND MOVEMENTS FROM SINGLE-CHANNEL FOREARM MUSCLE ACTIVITY

2011 ◽  
Vol 11 (03) ◽  
pp. 581-590 ◽  
Author(s):  
SRIDHAR P. ARJUNAN ◽  
DINESH K. KUMAR
Keyword(s):  
Muscle Contraction ◽  
Muscle Activity ◽  
Single Channel ◽  
Computer Interface ◽  
Hand Movements ◽  
Human Computer Interface ◽  
Wrist Flexion ◽  
Surface Electromyogram ◽  
Fractal Properties

Surface electromyogram (sEMG) has been used in the identification of various hand movements which can lead to a number of rehabilitation, medical, and human computer interface applications. These applications are currently in need of higher accuracy and become challenging because of its unreliability in the classification of sEMG when the level of muscle contraction is low and when there are multiple active muscles. The presence of noise and cross-talk from closely located and simultaneously active muscles is exaggerated when muscles are weakly active such as during sustained wrist and finger flexion. This study reports the use of fractal properties of sEMG to identify the small changes in strength of muscle contraction and the location of the active muscles. It is observed that the fractal dimension (FD) of the signal is related to the complexity of the muscle contraction while maximum fractal length (MFL) is related to the strength of contraction of the associated muscle. The results show that the MFL and FD of a single-channel sEMG from the forearm can be used to accurately identify a set of finger-and-wrist flexion-based actions even when the muscle activity is very weak. It is proposed that such a system could be used to control a prosthetic hand or for a human computer interface.

scholarly journals Auditory Verbal Cues Alter the Perceived Flavor of Beverages and Ease of Swallowing: A Psychometric and Electrophysiological Analysis

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Aya Nakamura ◽  
Satoshi Imaizumi
Keyword(s):  
Muscle Activity ◽  
Apple Juice ◽  
The Elderly ◽  
Verbal Cues ◽  
Positive Effects ◽  
Flavor Perception ◽  
Participant Group ◽  
Swallow Physiology ◽  
Suprahyoid Muscle ◽  
Elderly Participant

We investigated the possible effects of auditory verbal cues on flavor perception and swallow physiology for younger and elder participants. Apple juice, aojiru (grass) juice, and water were ingested with or without auditory verbal cues. Flavor perception and ease of swallowing were measured using a visual analog scale and swallow physiology by surface electromyography and cervical auscultation. The auditory verbal cues had significant positive effects on flavor and ease of swallowing as well as on swallow physiology. The taste score and the ease of swallowing score significantly increased when the participant’s anticipation was primed by accurate auditory verbal cues. There was no significant effect of auditory verbal cues on distaste score. Regardless of age, the maximum suprahyoid muscle activity significantly decreased when a beverage was ingested without auditory verbal cues. The interval between the onset of swallowing sounds and the peak timing point of the infrahyoid muscle activity significantly shortened when the anticipation induced by the cue was contradicted in the elderly participant group. These results suggest that auditory verbal cues can improve the perceived flavor of beverages and swallow physiology.

scholarly journals Classification of Chronic Kidney Disease in the Elderly: Pitfalls and Errors

2011 ◽  
Vol 119 (s1) ◽  
pp. c2-c4 ◽  
Author(s):  
Christopher G. Winearls ◽  
Richard J. Glassock
Keyword(s):  
Chronic Kidney Disease ◽  
Kidney Disease ◽  
The Elderly

Classification of abnormal behavior in the elderly based on Wi-Fi

2021 ◽  
Author(s):  
Wang Weiqiong ◽  
Cao Yongchun ◽  
Lin Qiang ◽  
Yifan Li
Keyword(s):  
The Elderly ◽  
Abnormal Behavior

scholarly journals Deep learning and taphonomy: high accuracy in the classification of cut marks made on fleshed and defleshed bones using convolutional neural networks

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Gabriel Cifuentes-Alcobendas ◽  
Manuel Domínguez-Rodrigo
Keyword(s):  
Machine Learning ◽  
Accurate Method ◽  
High Accuracy ◽  
Machine Learning Algorithms ◽  
Accurate Identification ◽  
Cut Marks ◽  
Eating Meat ◽  
Microscopic Features ◽  
Immense Potential

AbstractAccurate identification of bone surface modifications (BSM) is crucial for the taphonomic understanding of archaeological and paleontological sites. Critical interpretations of when humans started eating meat and animal fat or when they started using stone tools, or when they occupied new continents or interacted with predatory guilds impinge on accurate identifications of BSM. Until now, interpretations of Plio-Pleistocene BSM have been contentious because of the high uncertainty in discriminating among taphonomic agents. Recently, the use of machine learning algorithms has yielded high accuracy in the identification of BSM. A branch of machine learning methods based on imaging, computer vision (CV), has opened the door to a more objective and accurate method of BSM identification. The present work has selected two extremely similar types of BSM (cut marks made on fleshed an defleshed bones) to test the immense potential of artificial intelligence methods. This CV approach not only produced the highest accuracy in the classification of these types of BSM until present (95% on complete images of BSM and 88.89% of images of only internal mark features), but it also has enabled a method for determining which inconspicuous microscopic features determine successful BSM discrimination. The potential of this method in other areas of taphonomy and paleobiology is enormous.

scholarly journals Comparative Study of Internal Fixation of the Ulna and Distal Ulna Resection in Patients Older Than 70 Years With Distal Radius and Distal Metaphyseal Ulna Fractures

Hand ◽  
2018 ◽  
Vol 14 (4) ◽  
pp. 540-546
Author(s):  
Jorge G. Boretto ◽  
Ezequiel E. Zaidenberg ◽  
Gerardo L. Gallucci ◽  
Alejandro Sarme ◽  
Pablo De Carli
Keyword(s):  
Internal Fixation ◽  
Distal Radius ◽  
The Elderly ◽  
Acute Management ◽  
Distal Ulna ◽  
Radiographic Appearance ◽  
Patient Demographics ◽  
Ulna Fractures

Background: Acute management of fractures of the distal ulna that are associated with fractures of the distal radius remains difficult, particularly in the elderly. Methods: In this study, we investigated whether internal fixation of the distal ulna is associated with a higher rate of complications than resection of the distal ulna in patients older than 70 years. Twenty-four consecutive patients were included in this study, 12 of whom had undergone open reduction and internal fixation (ORIF) of the distal ulna, and 12 who had undergone distal ulna resection. Patients were retrospectively assessed for range of motion, grip strength, pain, and radiographic appearance. The functional outcome was evaluated by the Mayo Wrist Score. Complications were classified according to the Classification of Surgical Complications. Results: There were no differences in patient demographics between the 2 groups, except patient age. Clinical evaluation showed no difference at follow-up; however, there were significantly more complications associated with ORIF compared with resection. Conclusions: The results from our study show that women older than 70 years with fracture of the distal radius and distal ulna have a higher rate of complications if ORIF of the distal ulna is performed. Patients should be warned, by surgeons, of this in cases where ORIF of the distal ulna is suggested.

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