Abstract：
:The present paper compares the performance of two Hilbert spectral analyses when applied to a synthetic RR series from a nonstationary integral pulse frequency modulation model and to real RR series from a dataset of normal sinus arrhythmia. The Hilbert-Huang transformation based on empirical mode decomposition is compared to the presently introduced Hilbert-Olhede-Walden transformation based on stationary wavelet packet decomposition. The comparison gives consistent results pointing to a superior performance of the Hilbert-Olhede-Walden transformation showing 33-163 times smaller deviations when estimating the instantaneous frequency traces of the synthetic RR series. Artificial fluctuations caused by mode mixing in the Hilbert-Huang spectrum are seen in both the synthetic and real RR series. It can be concluded that the instantaneous frequencies and amplitudes estimated by the Hilbert-Huang transformation should be interpreted with caution when investigating heart rate variability.
journal_name
Med Biol Eng Computjournal_title
Medical & biological engineering & computingauthors
Ihlen EAdoi
10.1007/s11517-009-0500-xsubject
Has Abstractpub_date
2009-10-01 00:00:00pages
1035-44issue
10eissn
0140-0118issn
1741-0444journal_volume
47pub_type
杂志文章abstract：:Multi-scale modeling of the musculoskeletal system plays an essential role in the deep understanding of complex mechanisms underlying the biological phenomena and processes such as bone metabolic processes. Current multi-scale models suffer from the isolation of sub-models at each anatomical scale. The objective of th...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章,评审
doi：10.1007/s11517-016-1572-z
更新日期：2017-06-01 00:00:00
abstract：:Blood oxygenation level is an important measure that can be used alongside functional magnetic resonance imaging data in order to obtain closer correlates of neuronal activation. A robust estimate of this measure has thus far not been demonstrated. This is mainly due to the lack of knowledge of the underlying paramete...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-012-0886-8
更新日期：2012-05-01 00:00:00
abstract：:A method for the estimation of medium rate transitions of non-stationary electroencephalograms (EEG) is proposed. The method is applicable to such EEG dynamics that are between (a) fast transitions for which segmentation procedures are used and (b) slow transitions for which adaptive filters work properly. The estimat...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02513305
更新日期：1999-05-01 00:00:00
abstract：:In the present study, well known scale-space filtering (SSF) algorithm is used in combination with a linear mapping approach (LMA) to obtain clear auditory evoked potential (EP) waveform. The proposed combination involves two sequential steps: At first, the EEG noise level is reduced from -5 to 0 dB owing to the LMA b...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-009-0450-3
更新日期：2009-04-01 00:00:00
abstract：:The problem of excess cerebrospinal fluid in the brain (hydrocephalus) is generally managed using a passive pressure or flow regulated mechanical shunt. Despite the success of such devices, they have been plagued with a number of problems. It is desirable to have a shunt valve that responds dynamically to the changing...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-010-0716-9
更新日期：2011-01-01 00:00:00
abstract：:The mechanism of brain contusion has been investigated using a series of three-dimensional (3D) finite element analyses. A head injury model was used to simulate forward and backward rotation around the upper cervical vertebra. Intracranial pressure and shear stress responses were calculated and compared. The results ...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02347044
更新日期：2000-05-01 00:00:00
abstract：:Selective laser sintering (SLS) is a solid freeform fabrication technique, developed by Carl Deckard for his master's thesis at the University of Texas, patented in 1989. SLS manufacturing is a technique that produces physical models through a selective solidification of a variety of fine powders. SLS technology is ge...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章,评审
doi：10.1007/s11517-012-1001-x
更新日期：2013-03-01 00:00:00
abstract：:A biphasic continuum model for the flow of intraocular fluid, the aqueous humour, in the trabecular meshwork is proposed in the paper. The model considers the meshwork as a circular ring with uniform thickness of homogeneous, isotropic, viscoelastic material swollen with continuously percolating aqueous humour. The mo...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02446710
更新日期：1991-05-01 00:00:00
abstract：:Neurofilaments are organised into parallel bundles in axons through crossbridges formed by lateral projections of neurofilament subunits. Pure neurofilaments form gels in vitro, consisting of interconnected parallel arrays of filaments regulated by the phosphorylation level of neurofilament subunits. Neurofilament-ass...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02522486
更新日期：1998-05-01 00:00:00
abstract：:Most tissues are subject to some form of physiological mechanical loading which results in deformation of the cells triggering intracellular mechanotransduction pathways. This response to loading is generally essential for the health of the tissue, although more pronounced deformation may result in cell and tissue dam...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章,评审
doi：10.1007/s11517-008-0381-4
更新日期：2008-10-01 00:00:00
abstract：:Four ventricular fibrillation (VF) detection techniques were assessed using recordings of VF to evaluate sensitivity and VF-like recordings to evaluate specificity. The recordings were obtained from Coronary Care Unit patients. The techniques were: threshold crossing intervals (TCI); peaks in the autocorrelation funct...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02446668
更新日期：1993-03-01 00:00:00
abstract：:Dengue fever detection and classification have a vital role due to the recent outbreaks of different kinds of dengue fever. Recently, the advancement in the microarray technology can be employed for such classification process. Several studies have established that the gene selection phase takes a significant role in ...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-017-1722-y
更新日期：2018-04-01 00:00:00
abstract：:The purpose of this study was to evaluate the effect of increased blood flow on angiogenesis at the large vessels. The arteriovenous (AV) shunt was made on the thigh of male Wistar rats (n = 27) to increase blood flow, wrapped with artificial skin dermis, which consisted of a silicon outer layer, and isolated from sur...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02345133
更新日期：2005-01-01 00:00:00
abstract：:Bone mass and microarchitecture are the main determinants of bone strength. Three-dimensional micro-computed tomography has the potential to examine complete bones of small laboratory animals with very high resolution in a non-invasive way. In the presented work, the proximal part of the tibiae of hindlimb unloaded an...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02347054
更新日期：2000-05-01 00:00:00
abstract：:Atrial fibrillation (AF) is the most common cardiac arrhythmia with episodes that may terminate spontaneously in the first stages of the disease. On the other hand, when the arrhythmia is not self-terminating, normal sinus rhythm (NSR) restoration use to be required to reduce the risk of stroke and improve cardiac out...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-008-0348-5
更新日期：2008-07-01 00:00:00
abstract：:A mathematical model has been developed to facilitate indirect measurements of difficult to measure variables of the human energy metabolism on a daily basis. The model performs recursive system identification of the parameters of the metabolic model of the human energy metabolism using the law of conservation of ener...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-016-1552-3
更新日期：2017-05-01 00:00:00
abstract：:In the routine recording of magnetocardiograms (MCGs), it is necessary to underline the problem of noise cancellation. Source separation has often been suggested to solve this problem. In this paper, blind source separation (BSS), by means of singular value decomposition (SVD) and independent component analysis (ICA),...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-006-0055-z
更新日期：2006-06-01 00:00:00
abstract：:A method for making a current-ratio map to determine the ischaemic area of angina pectoris (AP) patients has been developed. This method uses a current-arrow map calculated using a ORS wave from 64-channel magnetocardiogram (MCG) signals. The current-ratio map can be calculated from the ratio of an exercise-induced cu...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02345263
更新日期：2001-01-01 00:00:00
abstract：:This study analyzes the performance of knee extension and flexion of Taekwondo and Kickboxing athletes. The power values were extracted through electromyography obtained by an isokinetic dynamometer at 60 degrees per second. These values are resulted from the square of the electromyography signal. The analysis of kick...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-010-0608-z
更新日期：2010-06-01 00:00:00
abstract：:Sealing resistance is highly significant with respect to the electrical neuron-electrode contact because it decreases the stimulation threshold of neurons cultured on a planar micro-electrode array. A method is proposed for measurement of the sealing resistance using impedance spectroscopy. The effect of the sealing r...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02524436
更新日期：1998-09-01 00:00:00
abstract：:The aim of this study was to design a new approach for the acquisition of regional radial strain from the middle portion of the interventricular septum. We designed and wrote a program in Matlab (computer-assisted method) for use on a personal computer so that the septum thickness throughout the cardiac cycle could be...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-007-0222-x
更新日期：2007-09-01 00:00:00
abstract：:The mastering of pulmonary auscultation requires complex acoustic skills. Computer-assisted learning tools (CALTs) have potential to enhance the learning of these skills; however, few have been developed for this purpose and do not integrate all the required features. Thus, this study aimed to assess the usability of ...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-017-1697-8
更新日期：2018-04-01 00:00:00
abstract：:The aim of the study is to establish the validity of the use of the electrical impedance technique for estimating local oedema in extremities through comparison with computed-tomography (CT) analysis. Eight healthy women (group 1) and nine women with unilateral leg oedema following chronic lymphatic obstruction (group...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02522859
更新日期：1998-01-01 00:00:00
abstract：:A hypothetical neuromusculoskeletal model is developed to simulate human normal walking and its modulated behaviors. A small set of neural periodic patterns drive spinal muscle synergies which in turn lead to specific pattern of muscle activation and supraspinal feedback systems maintain postural balance during walkin...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-007-0277-8
更新日期：2008-02-01 00:00:00
abstract：:In daily life, a person's gait-an important marker for his/her health status-is usually assessed using inertial sensors fixed to lower limbs or trunk. Such sensor locations are not well suited for continuous and long duration measurements. A better location would be the wrist but with the drawback of the presence of p...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-017-1621-2
更新日期：2017-10-01 00:00:00
abstract：:Tooth mobility examination is important in planning dental treatment, as it may give an indication of alveolar bone loss and the condition of the periodontal ligament. In clinical dental diagnosis a manual tooth mobility examination is useful. However, its determination of tooth mobility is subjective and depends on t...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02442173
更新日期：1989-01-01 00:00:00
abstract：:The vagus nerves convey both afferent and efferent information about autonomic activity related to cardiovascular functions. Those functions have been shown to change due to epileptic seizures, which suggests that ictal events might be detected via the vagus electroneurogram (VENG). In this study, we characterize the ...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-011-0782-7
更新日期：2011-09-01 00:00:00
abstract：:The main constituent of an ultrasound contrast agent (UCA) is gas-filled microbubbles. An average UCA contains billions per ml. These microbubbles are excellent ultrasound scatterers due to their high compressibility. In an ultrasound field they act as resonant systems, resulting in harmonic energy in the backscattere...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-009-0497-1
更新日期：2009-08-01 00:00:00
abstract：:The paper describes a method of quantifying Duchenne muscular dystrophy which is examiner independent and uses surface electromyographic signals (EMG). A standardised protocol is proposed. Spectral parameters are first computed from digitised EMG, then a polynomial model is deduced from the evolution of each parameter...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02446966
更新日期：1992-05-01 00:00:00
abstract：:A computer-controlled pump for use both in the study of vascular haemodynamics and in the calibration of clinical devices which measure blood flow is designed. The novel design of this pump incorporates two rack-mounted pistons, driven into opposing cylinders by a micro-stepping motor. This approach allows the product...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02446086
更新日期：1991-11-01 00:00:00
