Analysis of body responses to an accelerating platform by the largest-Lyapunov-exponent method
Abstract Various disciplines have benefited from the advent of high-performance computing in achieving practical solutions to their problems, and the area of health care is no exception to this. Non-linear signal-processing tools have been developed to understand the hidden complexity of the time se...
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| Veröffentlicht in: | Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine Journal of engineering in medicine, 2009-01, Vol.223 (1), p.111-120 |
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| container_title | Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine |
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| creator | Acharya, U R Goh, S C Iijima, K Sekine, M Tamura, T |
| description | Abstract
Various disciplines have benefited from the advent of high-performance computing in achieving practical solutions to their problems, and the area of health care is no exception to this. Non-linear signal-processing tools have been developed to understand the hidden complexity of the time series, and these will help clinicians in diagnosis and treatment. Postural study helps the elderly and people with a balancing problem due to various pathological conditions. In elderly subjects, falls are common and may result in injury. Correct postural balance is basic to well-being and it influences our daily life significantly. These postural signals are non-stationary; they may appear to be random in the time scale and it is difficult to observe the subtle changes for the human observer. Hence, more hidden information can be obtained from the signal using non-linear parameters. In this paper, ten young normal subjects are subjected to the balancing platform whose acceleration is gradually increased from 1 m/s2 to 5 m/s2 to study the postural response. The ankle front—back acceleration and ankle pitch angular velocity sensor data were studied using the largest Lyapunov exponent (LLE). The results show that for higher acceleration of the platform the ankle movement follows a particular rhythm, resulting in a lower Lyapunov exponent. During lower acceleration of the balancing platform, this value is higher because of the random movement of the ankle. In this work, the pattern of the body response was studied using LLE values for different accelerations using ankle data as the base signal for the normal subjects. |
| doi_str_mv | 10.1243/09544119JEIM454 |
| format | Article |
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Various disciplines have benefited from the advent of high-performance computing in achieving practical solutions to their problems, and the area of health care is no exception to this. Non-linear signal-processing tools have been developed to understand the hidden complexity of the time series, and these will help clinicians in diagnosis and treatment. Postural study helps the elderly and people with a balancing problem due to various pathological conditions. In elderly subjects, falls are common and may result in injury. Correct postural balance is basic to well-being and it influences our daily life significantly. These postural signals are non-stationary; they may appear to be random in the time scale and it is difficult to observe the subtle changes for the human observer. Hence, more hidden information can be obtained from the signal using non-linear parameters. In this paper, ten young normal subjects are subjected to the balancing platform whose acceleration is gradually increased from 1 m/s2 to 5 m/s2 to study the postural response. The ankle front—back acceleration and ankle pitch angular velocity sensor data were studied using the largest Lyapunov exponent (LLE). The results show that for higher acceleration of the platform the ankle movement follows a particular rhythm, resulting in a lower Lyapunov exponent. During lower acceleration of the balancing platform, this value is higher because of the random movement of the ankle. In this work, the pattern of the body response was studied using LLE values for different accelerations using ankle data as the base signal for the normal subjects.</description><identifier>ISSN: 0954-4119</identifier><identifier>EISSN: 2041-3033</identifier><identifier>DOI: 10.1243/09544119JEIM454</identifier><identifier>PMID: 19239072</identifier><language>eng</language><publisher>London, England: SAGE Publications</publisher><subject>Acceleration ; Adult ; Angular velocity ; Ankle ; Balance ; Balances (scales) ; Complexity ; Computer Simulation ; Diagnosis ; Dynamical systems ; Falls ; Feedback - physiology ; Female ; Geriatrics ; Health care ; Humans ; Injuries ; Knee ; Liapunov exponents ; Male ; Mathematical models ; Models, Biological ; Movement - physiology ; Nonlinearity ; Older people ; Physical Stimulation - methods ; Postural Balance - physiology ; Posture ; Posture - physiology ; Reflex - physiology ; Rhythm ; Sensors ; Signal processing ; Temporal variations ; Time series ; Velocity ; Well being</subject><ispartof>Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine, 2009-01, Vol.223 (1), p.111-120</ispartof><rights>2009 Institution of Mechanical Engineers</rights><rights>Copyright Professional Engineering Publishing Ltd Jan 2009</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c450t-4baf7c2d17f168aafe7e32bfd05b96ea277c38eb69fef49c9a070bb42bb35fa33</citedby><cites>FETCH-LOGICAL-c450t-4baf7c2d17f168aafe7e32bfd05b96ea277c38eb69fef49c9a070bb42bb35fa33</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktopdf>$$Uhttps://journals.sagepub.com/doi/pdf/10.1243/09544119JEIM454$$EPDF$$P50$$Gsage$$H</linktopdf><linktohtml>$$Uhttps://journals.sagepub.com/doi/10.1243/09544119JEIM454$$EHTML$$P50$$Gsage$$H</linktohtml><link.rule.ids>314,778,782,21802,27907,27908,43604,43605</link.rule.ids><backlink>$$Uhttps://www.ncbi.nlm.nih.gov/pubmed/19239072$$D View this record in MEDLINE/PubMed$$Hfree_for_read</backlink></links><search><creatorcontrib>Acharya, U R</creatorcontrib><creatorcontrib>Goh, S C</creatorcontrib><creatorcontrib>Iijima, K</creatorcontrib><creatorcontrib>Sekine, M</creatorcontrib><creatorcontrib>Tamura, T</creatorcontrib><title>Analysis of body responses to an accelerating platform by the largest-Lyapunov-exponent method</title><title>Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine</title><addtitle>Proc Inst Mech Eng H</addtitle><description>Abstract
Various disciplines have benefited from the advent of high-performance computing in achieving practical solutions to their problems, and the area of health care is no exception to this. Non-linear signal-processing tools have been developed to understand the hidden complexity of the time series, and these will help clinicians in diagnosis and treatment. Postural study helps the elderly and people with a balancing problem due to various pathological conditions. In elderly subjects, falls are common and may result in injury. Correct postural balance is basic to well-being and it influences our daily life significantly. These postural signals are non-stationary; they may appear to be random in the time scale and it is difficult to observe the subtle changes for the human observer. Hence, more hidden information can be obtained from the signal using non-linear parameters. In this paper, ten young normal subjects are subjected to the balancing platform whose acceleration is gradually increased from 1 m/s2 to 5 m/s2 to study the postural response. The ankle front—back acceleration and ankle pitch angular velocity sensor data were studied using the largest Lyapunov exponent (LLE). The results show that for higher acceleration of the platform the ankle movement follows a particular rhythm, resulting in a lower Lyapunov exponent. During lower acceleration of the balancing platform, this value is higher because of the random movement of the ankle. In this work, the pattern of the body response was studied using LLE values for different accelerations using ankle data as the base signal for the normal subjects.</description><subject>Acceleration</subject><subject>Adult</subject><subject>Angular velocity</subject><subject>Ankle</subject><subject>Balance</subject><subject>Balances (scales)</subject><subject>Complexity</subject><subject>Computer Simulation</subject><subject>Diagnosis</subject><subject>Dynamical systems</subject><subject>Falls</subject><subject>Feedback - physiology</subject><subject>Female</subject><subject>Geriatrics</subject><subject>Health care</subject><subject>Humans</subject><subject>Injuries</subject><subject>Knee</subject><subject>Liapunov exponents</subject><subject>Male</subject><subject>Mathematical models</subject><subject>Models, Biological</subject><subject>Movement - physiology</subject><subject>Nonlinearity</subject><subject>Older people</subject><subject>Physical Stimulation - methods</subject><subject>Postural Balance - physiology</subject><subject>Posture</subject><subject>Posture - physiology</subject><subject>Reflex - physiology</subject><subject>Rhythm</subject><subject>Sensors</subject><subject>Signal processing</subject><subject>Temporal variations</subject><subject>Time series</subject><subject>Velocity</subject><subject>Well being</subject><issn>0954-4119</issn><issn>2041-3033</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2009</creationdate><recordtype>article</recordtype><sourceid>EIF</sourceid><sourceid>ABUWG</sourceid><sourceid>AFKRA</sourceid><sourceid>AZQEC</sourceid><sourceid>BENPR</sourceid><sourceid>CCPQU</sourceid><sourceid>DWQXO</sourceid><sourceid>GNUQQ</sourceid><recordid>eNqF0cFu1DAQBmCrArXbwrm3ygKpvRBqexx7fayqthQt4gJXIjsZb7dK4mAniLw9Xu1KVJUKJx_mm9-jGUJOOfvIhYRLZkopOTefb-6_yFIekIVgkhfAAF6RxbZabMtH5DilR8YY50wdkiNuBBimxYL8uOptO6dNosFTF5qZRkxD6BMmOgZqe2rrGluMdtz0azq0dvQhdtTNdHxA2tq4xjQWq9kOUx9-Ffg7N2M_0g7Hh9C8Ia-9bRO-3b8n5PvtzbfrT8Xq69399dWqqGXJxkI663UtGq49V0trPWoE4XzDSmcUWqF1DUt0ynj00tTGMs2ck8I5KL0FOCEXu9whhp9TnqjqNinP3doew5QqLQGEltJkef5PqZRRqtTsvxAASslBZvjuGXwMU8xrTZUAJZfCiDKj9y8hbpgUoJdqG3W5U3UMKUX01RA3nY1zxVm1PXj17OC542yfO7kOm79-f-EMPuxAsmt88ukLeX8Ay6qy-Q</recordid><startdate>20090101</startdate><enddate>20090101</enddate><creator>Acharya, U R</creator><creator>Goh, S C</creator><creator>Iijima, K</creator><creator>Sekine, M</creator><creator>Tamura, T</creator><general>SAGE Publications</general><general>SAGE PUBLICATIONS, INC</general><scope>CGR</scope><scope>CUY</scope><scope>CVF</scope><scope>ECM</scope><scope>EIF</scope><scope>NPM</scope><scope>AAYXX</scope><scope>CITATION</scope><scope>7QF</scope><scope>7QO</scope><scope>7QQ</scope><scope>7SC</scope><scope>7SE</scope><scope>7SP</scope><scope>7SR</scope><scope>7TA</scope><scope>7TB</scope><scope>7U5</scope><scope>8BQ</scope><scope>8FD</scope><scope>F28</scope><scope>FR3</scope><scope>H8D</scope><scope>H8G</scope><scope>JG9</scope><scope>JQ2</scope><scope>K9.</scope><scope>KR7</scope><scope>L7M</scope><scope>L~C</scope><scope>L~D</scope><scope>P64</scope><scope>3V.</scope><scope>7X7</scope><scope>7XB</scope><scope>88A</scope><scope>88E</scope><scope>88I</scope><scope>8AO</scope><scope>8FE</scope><scope>8FG</scope><scope>8FH</scope><scope>8FI</scope><scope>8FJ</scope><scope>8FK</scope><scope>ABJCF</scope><scope>ABUWG</scope><scope>AFKRA</scope><scope>AZQEC</scope><scope>BBNVY</scope><scope>BENPR</scope><scope>BGLVJ</scope><scope>BHPHI</scope><scope>CCPQU</scope><scope>DWQXO</scope><scope>FYUFA</scope><scope>GHDGH</scope><scope>GNUQQ</scope><scope>HCIFZ</scope><scope>L6V</scope><scope>LK8</scope><scope>M0S</scope><scope>M1P</scope><scope>M2P</scope><scope>M7P</scope><scope>M7S</scope><scope>PQEST</scope><scope>PQQKQ</scope><scope>PQUKI</scope><scope>PRINS</scope><scope>PTHSS</scope><scope>Q9U</scope><scope>7X8</scope></search><sort><creationdate>20090101</creationdate><title>Analysis of body responses to an accelerating platform by the largest-Lyapunov-exponent method</title><author>Acharya, U R ; Goh, S C ; Iijima, K ; Sekine, M ; Tamura, T</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c450t-4baf7c2d17f168aafe7e32bfd05b96ea277c38eb69fef49c9a070bb42bb35fa33</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2009</creationdate><topic>Acceleration</topic><topic>Adult</topic><topic>Angular velocity</topic><topic>Ankle</topic><topic>Balance</topic><topic>Balances (scales)</topic><topic>Complexity</topic><topic>Computer Simulation</topic><topic>Diagnosis</topic><topic>Dynamical systems</topic><topic>Falls</topic><topic>Feedback - physiology</topic><topic>Female</topic><topic>Geriatrics</topic><topic>Health care</topic><topic>Humans</topic><topic>Injuries</topic><topic>Knee</topic><topic>Liapunov exponents</topic><topic>Male</topic><topic>Mathematical models</topic><topic>Models, Biological</topic><topic>Movement - physiology</topic><topic>Nonlinearity</topic><topic>Older people</topic><topic>Physical Stimulation - methods</topic><topic>Postural Balance - physiology</topic><topic>Posture</topic><topic>Posture - physiology</topic><topic>Reflex - physiology</topic><topic>Rhythm</topic><topic>Sensors</topic><topic>Signal processing</topic><topic>Temporal variations</topic><topic>Time series</topic><topic>Velocity</topic><topic>Well being</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Acharya, U R</creatorcontrib><creatorcontrib>Goh, S C</creatorcontrib><creatorcontrib>Iijima, K</creatorcontrib><creatorcontrib>Sekine, M</creatorcontrib><creatorcontrib>Tamura, T</creatorcontrib><collection>Medline</collection><collection>MEDLINE</collection><collection>MEDLINE (Ovid)</collection><collection>MEDLINE</collection><collection>MEDLINE</collection><collection>PubMed</collection><collection>CrossRef</collection><collection>Aluminium Industry Abstracts</collection><collection>Biotechnology Research Abstracts</collection><collection>Ceramic Abstracts</collection><collection>Computer and Information Systems Abstracts</collection><collection>Corrosion Abstracts</collection><collection>Electronics & Communications Abstracts</collection><collection>Engineered Materials Abstracts</collection><collection>Materials Business File</collection><collection>Mechanical & Transportation Engineering Abstracts</collection><collection>Solid State and Superconductivity Abstracts</collection><collection>METADEX</collection><collection>Technology Research Database</collection><collection>ANTE: Abstracts in New Technology & Engineering</collection><collection>Engineering Research Database</collection><collection>Aerospace Database</collection><collection>Copper Technical Reference Library</collection><collection>Materials Research Database</collection><collection>ProQuest Computer Science Collection</collection><collection>ProQuest Health & Medical Complete (Alumni)</collection><collection>Civil Engineering Abstracts</collection><collection>Advanced Technologies Database with Aerospace</collection><collection>Computer and Information Systems Abstracts Academic</collection><collection>Computer and Information Systems Abstracts Professional</collection><collection>Biotechnology and BioEngineering Abstracts</collection><collection>ProQuest Central (Corporate)</collection><collection>Health & Medical Collection</collection><collection>ProQuest Central (purchase pre-March 2016)</collection><collection>Biology Database (Alumni Edition)</collection><collection>Medical Database (Alumni Edition)</collection><collection>Science Database (Alumni Edition)</collection><collection>ProQuest Pharma Collection</collection><collection>ProQuest SciTech Collection</collection><collection>ProQuest Technology Collection</collection><collection>ProQuest Natural Science Collection</collection><collection>Hospital Premium Collection</collection><collection>Hospital Premium Collection (Alumni Edition)</collection><collection>ProQuest Central (Alumni) (purchase pre-March 2016)</collection><collection>Materials Science & Engineering Collection</collection><collection>ProQuest Central (Alumni Edition)</collection><collection>ProQuest Central UK/Ireland</collection><collection>ProQuest Central Essentials</collection><collection>Biological Science Collection</collection><collection>ProQuest Central</collection><collection>Technology Collection (ProQuest)</collection><collection>Natural Science Collection (ProQuest)</collection><collection>ProQuest One Community College</collection><collection>ProQuest Central Korea</collection><collection>Health Research Premium Collection</collection><collection>Health Research Premium Collection (Alumni)</collection><collection>ProQuest Central Student</collection><collection>SciTech Premium Collection</collection><collection>ProQuest Engineering Collection</collection><collection>ProQuest Biological Science Collection</collection><collection>Health & Medical Collection (Alumni Edition)</collection><collection>Medical Database</collection><collection>Science Database (ProQuest)</collection><collection>Biological Science Database</collection><collection>Engineering Database</collection><collection>ProQuest One Academic Eastern Edition (DO NOT USE)</collection><collection>ProQuest One Academic</collection><collection>ProQuest One Academic UKI Edition</collection><collection>ProQuest Central China</collection><collection>Engineering Collection</collection><collection>ProQuest Central Basic</collection><collection>MEDLINE - 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Part H, Journal of engineering in medicine</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Acharya, U R</au><au>Goh, S C</au><au>Iijima, K</au><au>Sekine, M</au><au>Tamura, T</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Analysis of body responses to an accelerating platform by the largest-Lyapunov-exponent method</atitle><jtitle>Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine</jtitle><addtitle>Proc Inst Mech Eng H</addtitle><date>2009-01-01</date><risdate>2009</risdate><volume>223</volume><issue>1</issue><spage>111</spage><epage>120</epage><pages>111-120</pages><issn>0954-4119</issn><eissn>2041-3033</eissn><abstract>Abstract
Various disciplines have benefited from the advent of high-performance computing in achieving practical solutions to their problems, and the area of health care is no exception to this. Non-linear signal-processing tools have been developed to understand the hidden complexity of the time series, and these will help clinicians in diagnosis and treatment. Postural study helps the elderly and people with a balancing problem due to various pathological conditions. In elderly subjects, falls are common and may result in injury. Correct postural balance is basic to well-being and it influences our daily life significantly. These postural signals are non-stationary; they may appear to be random in the time scale and it is difficult to observe the subtle changes for the human observer. Hence, more hidden information can be obtained from the signal using non-linear parameters. In this paper, ten young normal subjects are subjected to the balancing platform whose acceleration is gradually increased from 1 m/s2 to 5 m/s2 to study the postural response. The ankle front—back acceleration and ankle pitch angular velocity sensor data were studied using the largest Lyapunov exponent (LLE). The results show that for higher acceleration of the platform the ankle movement follows a particular rhythm, resulting in a lower Lyapunov exponent. During lower acceleration of the balancing platform, this value is higher because of the random movement of the ankle. In this work, the pattern of the body response was studied using LLE values for different accelerations using ankle data as the base signal for the normal subjects.</abstract><cop>London, England</cop><pub>SAGE Publications</pub><pmid>19239072</pmid><doi>10.1243/09544119JEIM454</doi><tpages>10</tpages></addata></record> |
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| subjects | Acceleration Adult Angular velocity Ankle Balance Balances (scales) Complexity Computer Simulation Diagnosis Dynamical systems Falls Feedback - physiology Female Geriatrics Health care Humans Injuries Knee Liapunov exponents Male Mathematical models Models, Biological Movement - physiology Nonlinearity Older people Physical Stimulation - methods Postural Balance - physiology Posture Posture - physiology Reflex - physiology Rhythm Sensors Signal processing Temporal variations Time series Velocity Well being |
| title | Analysis of body responses to an accelerating platform by the largest-Lyapunov-exponent method |
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