Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference最新文献
Non-invasive cardiac computed tomography angiography (CTA) is widely used to assess coronary artery stenosis and give clinical decision-making support to clinicians. The severity of stenosis lesion is commonly graded by a range of percent Diameter Stenosis (DS), which can introduce false positive diagnoses or over-estimation, triggering unnecessary further procedures. In this paper, a system and the associate methods to quantify stenosis by the percent Area Stenosis (AS) from cardiac CTA is presented. In the process, coronary artery tree is segmented and the centerline is extracted by Hessian filtering and the minimal path method. After a serial of 2D cross-sectional artery images along the artery centerline are obtained, lumen areas are segmented by ellipse-fitting with deformable models, and consequently to compute the lesion's AS. Experimental results on 5 CTA data sets show that compared to DS, AS better correlates to the reference standard for stenosis quantification, suggesting the efficacy of the proposed system.
{"title":"Quantification of coronary artery Stenosis by Area Stenosis from cardiac CT angiography.","authors":"Jiayin Zhou, Weimin Huang, Yanling Chi, Yuping Duan, Liang Zhong, Xiaodan Zhao, Junmei Zhang, Wei Xiong, Ru San Tan, Kyaw Kyar Toe","doi":"10.1109/EMBC.2015.7318457","DOIUrl":"https://doi.org/10.1109/EMBC.2015.7318457","url":null,"abstract":"Non-invasive cardiac computed tomography angiography (CTA) is widely used to assess coronary artery stenosis and give clinical decision-making support to clinicians. The severity of stenosis lesion is commonly graded by a range of percent Diameter Stenosis (DS), which can introduce false positive diagnoses or over-estimation, triggering unnecessary further procedures. In this paper, a system and the associate methods to quantify stenosis by the percent Area Stenosis (AS) from cardiac CTA is presented. In the process, coronary artery tree is segmented and the centerline is extracted by Hessian filtering and the minimal path method. After a serial of 2D cross-sectional artery images along the artery centerline are obtained, lumen areas are segmented by ellipse-fitting with deformable models, and consequently to compute the lesion's AS. Experimental results on 5 CTA data sets show that compared to DS, AS better correlates to the reference standard for stenosis quantification, suggesting the efficacy of the proposed system.","PeriodicalId":72689,"journal":{"name":"Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference","volume":"19 1","pages":"695-8"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82530458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study proposes a novel pseudo resistor structure with a tunable DC bias voltage for biomedical front-end amplifiers (FEAs). In the proposed FEA, the high-pass filter composed of differential difference amplifier and a pseudo resistor is implemented. The FEA is manufactured by using a standard TSMC 0.35 μm CMOS process. In this study, three types FEAs included three different pseudo resistor are simulated, fabricated and measured for comparison and electrocorticography (ECoG) measurement, and all the results show the proposed pseudo resistor is superior to other two types in bandwidth. In chip implementation, the lower and upper cutoff frequencies of the high-pass filter with the proposed pseudo resistor are 0.15 Hz and 4.98 KHz, respectively. It also demonstrates lower total harmonic distortion performance of -58 dB at 1 kHz and higher stability with wide supply range (1.8 V and 3.3 V) and control voltage range (0.9 V and 1.65 V) than others. Moreover, the FEA with the proposed pseudo successfully recorded spike-and-wave discharges of ECoG signal in in vivo experiment on rat with pentylenetetrazol-induced seizures.
{"title":"A novel pseudo resistor structure for biomedical front-end amplifiers.","authors":"Yu-Chieh Huang, Tzu-Sen Yang, Shun-Hsi Hsu, Xin-Zhuang Chen, Jin-Chern Chiou","doi":"10.1109/EMBC.2015.7318952","DOIUrl":"https://doi.org/10.1109/EMBC.2015.7318952","url":null,"abstract":"This study proposes a novel pseudo resistor structure with a tunable DC bias voltage for biomedical front-end amplifiers (FEAs). In the proposed FEA, the high-pass filter composed of differential difference amplifier and a pseudo resistor is implemented. The FEA is manufactured by using a standard TSMC 0.35 μm CMOS process. In this study, three types FEAs included three different pseudo resistor are simulated, fabricated and measured for comparison and electrocorticography (ECoG) measurement, and all the results show the proposed pseudo resistor is superior to other two types in bandwidth. In chip implementation, the lower and upper cutoff frequencies of the high-pass filter with the proposed pseudo resistor are 0.15 Hz and 4.98 KHz, respectively. It also demonstrates lower total harmonic distortion performance of -58 dB at 1 kHz and higher stability with wide supply range (1.8 V and 3.3 V) and control voltage range (0.9 V and 1.65 V) than others. Moreover, the FEA with the proposed pseudo successfully recorded spike-and-wave discharges of ECoG signal in in vivo experiment on rat with pentylenetetrazol-induced seizures.","PeriodicalId":72689,"journal":{"name":"Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference","volume":"34 8","pages":"2713-6"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/EMBC.2015.7318952","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72410245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.1109/EMBC.2015.7319683
Lian Jin, Jianfei Wang, Biao Song, Xiaomei Wu, Zuxiang Fang
The objective of this study is to explore the possible ways to reduce defibrillation energy and further reveal the mechanism of electric defibrillation. A bidomain simulation study was performed on a rabbit whole-ventricle electrophysiological model and the feasibility of the defibrillation strategy with multi-electrodes stimulation was verified. Simulation results indicate that the new approach is effective in low-energy defibrillation.
{"title":"Low-energy defibrillation with multi-electrodes stimulation: A simulation study.","authors":"Lian Jin, Jianfei Wang, Biao Song, Xiaomei Wu, Zuxiang Fang","doi":"10.1109/EMBC.2015.7319683","DOIUrl":"https://doi.org/10.1109/EMBC.2015.7319683","url":null,"abstract":"The objective of this study is to explore the possible ways to reduce defibrillation energy and further reveal the mechanism of electric defibrillation. A bidomain simulation study was performed on a rabbit whole-ventricle electrophysiological model and the feasibility of the defibrillation strategy with multi-electrodes stimulation was verified. Simulation results indicate that the new approach is effective in low-energy defibrillation.","PeriodicalId":72689,"journal":{"name":"Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference","volume":"243 1","pages":"5688-91"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83490194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.1109/EMBC.2015.7320251
Chia-Hung Lee, Chien-Chong Hong
This paper presents a novel disposable emulsion droplet generation lab chip driven by vacuum module for monodisperse emulsions generation and blood cell encapsulation. Emulsion droplet is a powerful tool in miniaturized analysis systems for high throughput processing. It shows great potential in chemical and biological reactions like speeding up the reaction and reducing the cost of reagents. Most research groups use syringe pumps providing positive pressure to drive the fluids. However, the long tubing connection and high cost make the microfluidic systems complicate and unsuitable for lab-on-a-chip (LOC) device. In this paper, our emulsion droplet generation lab chip with disposable vacuum module, made of shape memory polymer, provides a negative pressure to drive the fluids. This lab chip could achieve creating monodisperse emulsion droplets by manipulating two-phase microfluidic within 1 set of vacuum module and mini-heater. In the meantime, the waste is gathered into the cavity of vacuum module. This makes this lab chip safe while using biological samples. The vacuum module shows the advantages of compact, simple structure, and east-to-attach with the microfluidic device and great performance in the experiments.
{"title":"A disposable emulsion droplet generation lab chips driven by vacuum module for manipulation of blood cells.","authors":"Chia-Hung Lee, Chien-Chong Hong","doi":"10.1109/EMBC.2015.7320251","DOIUrl":"https://doi.org/10.1109/EMBC.2015.7320251","url":null,"abstract":"This paper presents a novel disposable emulsion droplet generation lab chip driven by vacuum module for monodisperse emulsions generation and blood cell encapsulation. Emulsion droplet is a powerful tool in miniaturized analysis systems for high throughput processing. It shows great potential in chemical and biological reactions like speeding up the reaction and reducing the cost of reagents. Most research groups use syringe pumps providing positive pressure to drive the fluids. However, the long tubing connection and high cost make the microfluidic systems complicate and unsuitable for lab-on-a-chip (LOC) device. In this paper, our emulsion droplet generation lab chip with disposable vacuum module, made of shape memory polymer, provides a negative pressure to drive the fluids. This lab chip could achieve creating monodisperse emulsion droplets by manipulating two-phase microfluidic within 1 set of vacuum module and mini-heater. In the meantime, the waste is gathered into the cavity of vacuum module. This makes this lab chip safe while using biological samples. The vacuum module shows the advantages of compact, simple structure, and east-to-attach with the microfluidic device and great performance in the experiments.","PeriodicalId":72689,"journal":{"name":"Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference","volume":"40 1","pages":"8010-3"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85289024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.1109/EMBC.2015.7319971
Yina Wang, Shuoyu Wang
To support care giving in an aging society with a shrinking population, various life support robots are being developed. In the authors' laboratory, an excretion care support robot (ECSR) with human cooperative characteristic has been developed to relieve the burden of caregivers and improve the quality of life for bedridden persons. This robot consists of a portable toilet with storage tank and a mobile robot which can run autonomously to conduct the cooperative work with others. Our research is focused on how to improve the motion accuracy and how the robot can cooperate with users. In this paper, to enable the ECSR could precisely move in the indoor environment, a proper controller is proposed considering the center of gravity shift and load changes. Then, to perform the cooperative task, two acceleration sensors are used to recognize the users' intended posture and position when moving from bed to toilet. The robot's target angle and position are determined by the user's posture. The effectiveness of the proposed method is verified by a pseudo excretion support experiment.
{"title":"Development of an excretion care support robot with human cooperative characteristics.","authors":"Yina Wang, Shuoyu Wang","doi":"10.1109/EMBC.2015.7319971","DOIUrl":"https://doi.org/10.1109/EMBC.2015.7319971","url":null,"abstract":"To support care giving in an aging society with a shrinking population, various life support robots are being developed. In the authors' laboratory, an excretion care support robot (ECSR) with human cooperative characteristic has been developed to relieve the burden of caregivers and improve the quality of life for bedridden persons. This robot consists of a portable toilet with storage tank and a mobile robot which can run autonomously to conduct the cooperative work with others. Our research is focused on how to improve the motion accuracy and how the robot can cooperate with users. In this paper, to enable the ECSR could precisely move in the indoor environment, a proper controller is proposed considering the center of gravity shift and load changes. Then, to perform the cooperative task, two acceleration sensors are used to recognize the users' intended posture and position when moving from bed to toilet. The robot's target angle and position are determined by the user's posture. The effectiveness of the proposed method is verified by a pseudo excretion support experiment.","PeriodicalId":72689,"journal":{"name":"Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference","volume":"149 1","pages":"6868-71"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79704364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.1109/EMBC.2015.7319668
M. Hannula, A. Haaparanta, Ilmari Tamminen, A. Aula, M. Kellomaki, J. Hyttinen
Methods to image and assess the microstructure of polymer based biomaterials in liquid phase, for example cell culture medium, are well warranted. X-ray microtomography could provide a mean to visualize and analyze such structures. However, the density of such polymers is close to that of water and hence the X-ray contrast is poor. Moreover, if the biomaterials contain cells and are dried, the cell morphology may be distorted. In this paper we test phosphotungstic acid (PTA) staining to improve the contrast. We imaged collagen and PLA samples with μCT in air, water and alcohol. The methods were compared visually and with contrast to noise ratio calculated from the images. Our results demonstrate that with alcohol the PLA can be imaged also in liquid phase. PTA staining seems to be a good method to increase the contrast for collagen in μCT imaging.
{"title":"X-ray microtomography of collagen and polylactide scaffolds in liquids.","authors":"M. Hannula, A. Haaparanta, Ilmari Tamminen, A. Aula, M. Kellomaki, J. Hyttinen","doi":"10.1109/EMBC.2015.7319668","DOIUrl":"https://doi.org/10.1109/EMBC.2015.7319668","url":null,"abstract":"Methods to image and assess the microstructure of polymer based biomaterials in liquid phase, for example cell culture medium, are well warranted. X-ray microtomography could provide a mean to visualize and analyze such structures. However, the density of such polymers is close to that of water and hence the X-ray contrast is poor. Moreover, if the biomaterials contain cells and are dried, the cell morphology may be distorted. In this paper we test phosphotungstic acid (PTA) staining to improve the contrast. We imaged collagen and PLA samples with μCT in air, water and alcohol. The methods were compared visually and with contrast to noise ratio calculated from the images. Our results demonstrate that with alcohol the PLA can be imaged also in liquid phase. PTA staining seems to be a good method to increase the contrast for collagen in μCT imaging.","PeriodicalId":72689,"journal":{"name":"Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference","volume":"49 1","pages":"5626-9"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73821411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.1109/EMBC.2015.7319396
Dakun Lai, Pengye Li, Qi Xu
Compared with clinical and experimental approaches, numerical modeling of defibrillation offers a great opportunity to optimize the defibrillation strategy in a more individualized way. Through numerical simulation of the shock-induce electric field distribution, the outcome of a certain defibrillation shock could be predicted according to several different metrics. In this paper, we propose a novel evaluation method, in which four defibrillation criteria are assigned with separate weighting factors to quantitatively assess the efficiency of a certain defibrillation shock. Three anatomically realistic finite element models of swine were constructed for the evaluation study of 8 electrode pairs in different placements. In addition, corresponding animal experiments were performed to determine the defibrillation threshold of 8 electrode placements. Both computational and experimental results suggest that the clinical recommended anterior-lateral position is the most efficient electrode displacement for transthoracic defibrillation in swine. In conclusion, the good agreement between stimulations and experiments indicates that the present multi-criteria evaluation method would be potentially useful for optimizations of cardiac defibrillation outcome.
{"title":"A multi-criteria evaluation method for assessing the defibrillation outcome of different electrode placements in swine.","authors":"Dakun Lai, Pengye Li, Qi Xu","doi":"10.1109/EMBC.2015.7319396","DOIUrl":"https://doi.org/10.1109/EMBC.2015.7319396","url":null,"abstract":"Compared with clinical and experimental approaches, numerical modeling of defibrillation offers a great opportunity to optimize the defibrillation strategy in a more individualized way. Through numerical simulation of the shock-induce electric field distribution, the outcome of a certain defibrillation shock could be predicted according to several different metrics. In this paper, we propose a novel evaluation method, in which four defibrillation criteria are assigned with separate weighting factors to quantitatively assess the efficiency of a certain defibrillation shock. Three anatomically realistic finite element models of swine were constructed for the evaluation study of 8 electrode pairs in different placements. In addition, corresponding animal experiments were performed to determine the defibrillation threshold of 8 electrode placements. Both computational and experimental results suggest that the clinical recommended anterior-lateral position is the most efficient electrode displacement for transthoracic defibrillation in swine. In conclusion, the good agreement between stimulations and experiments indicates that the present multi-criteria evaluation method would be potentially useful for optimizations of cardiac defibrillation outcome.","PeriodicalId":72689,"journal":{"name":"Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference","volume":"7 1","pages":"4507-10"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77027553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.1109/EMBC.2015.7320231
Shasha Yang, Yin Wu
Chemical exchange saturation transfer (CEST) MRI emerges as a powerful imaging method to probe chemical exchange between bulk water and labile protons. Conventional CEST imaging needs detailed Z-spectrum acquisition, even at frequencies with limited information for CEST parameter quantification, which harms imaging efficiency and is not favorable in practical applications. In this study, a variable-density Z-spectrum acquisition scheme was proposed. Data with saturation frequencies close to water, labile protons and their negative frequency offset was densely sampled, while the remaining part was sparsely acquired. The accuracy of the proposed method in CEST ratio measurement was investigated with numerical simulation. Compared to the conventionally evenly distributed Z-spectrum acquisition method, the proposed scheme showed significant improvement of CEST ratio characterization with existence of noise and static magnetic field inhomogeneity. With the additional advantage of easy implementation, the developed Z-spectrum acquisition scheme provides a useful framework for accurate CEST parameter quantification without compromising the imaging time.
{"title":"Investigation of the performance of variable-density Z-spectrum acquisition scheme in MR chemical exchange saturation transfer effect quantification.","authors":"Shasha Yang, Yin Wu","doi":"10.1109/EMBC.2015.7320231","DOIUrl":"https://doi.org/10.1109/EMBC.2015.7320231","url":null,"abstract":"Chemical exchange saturation transfer (CEST) MRI emerges as a powerful imaging method to probe chemical exchange between bulk water and labile protons. Conventional CEST imaging needs detailed Z-spectrum acquisition, even at frequencies with limited information for CEST parameter quantification, which harms imaging efficiency and is not favorable in practical applications. In this study, a variable-density Z-spectrum acquisition scheme was proposed. Data with saturation frequencies close to water, labile protons and their negative frequency offset was densely sampled, while the remaining part was sparsely acquired. The accuracy of the proposed method in CEST ratio measurement was investigated with numerical simulation. Compared to the conventionally evenly distributed Z-spectrum acquisition method, the proposed scheme showed significant improvement of CEST ratio characterization with existence of noise and static magnetic field inhomogeneity. With the additional advantage of easy implementation, the developed Z-spectrum acquisition scheme provides a useful framework for accurate CEST parameter quantification without compromising the imaging time.","PeriodicalId":72689,"journal":{"name":"Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference","volume":"14 1","pages":"7929-32"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78297532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.1109/EMBC.2015.7318966
Xiaolong Ma, Guanghua Xu, Min Li, Jun Xie, Longting Chen, Wei Pei
The incidence of cervical vertebra spondylosis is increasing with the pace of life while there is no high-efficient measurement method. This study proposed a non-contact, high-efficient, and high-precisionmethod measuring the cervical vertebra activities which obtains the cervical vertebra activities by combining the function of skeletal tracking and face tracking. A comparison study between the proposed and traditional methods has been conducted here. Statistics shows that the efficiency of the proposed measurement method at least is 6 times faster than modified square shaped goniometers that is the represent of traditional measurement, and it's angular error in average is 0.35°. Moreover, the proposed measuring method has been tested in hospital clinical environment and the results show that the proposed method can be used easily and have little interference.
{"title":"Measuring cervical vertebra movements using kinect sensor.","authors":"Xiaolong Ma, Guanghua Xu, Min Li, Jun Xie, Longting Chen, Wei Pei","doi":"10.1109/EMBC.2015.7318966","DOIUrl":"https://doi.org/10.1109/EMBC.2015.7318966","url":null,"abstract":"The incidence of cervical vertebra spondylosis is increasing with the pace of life while there is no high-efficient measurement method. This study proposed a non-contact, high-efficient, and high-precisionmethod measuring the cervical vertebra activities which obtains the cervical vertebra activities by combining the function of skeletal tracking and face tracking. A comparison study between the proposed and traditional methods has been conducted here. Statistics shows that the efficiency of the proposed measurement method at least is 6 times faster than modified square shaped goniometers that is the represent of traditional measurement, and it's angular error in average is 0.35°. Moreover, the proposed measuring method has been tested in hospital clinical environment and the results show that the proposed method can be used easily and have little interference.","PeriodicalId":72689,"journal":{"name":"Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference","volume":"24 1","pages":"2771-4"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78846395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-01-01DOI: 10.1109/EMBC.2015.7318654
Zening Fu, Sheng Han, Ao Tan, Yiheng Tu, Zhiguo Zhang
Exploration of time-varying functional brain connectivity based on functional Magnetic Resonance Imaging (fMRI) data is important for understanding dynamic brain mechanisms. l1-penalized inverse covariance is a common measure for the inference of sparse structure of functional brain networks, and it has been recently extended to estimate time-varying sparse brain networks by using a sliding window and incorporating a smoothing constraint on temporal variation. However, l1 penalty cannot induce maximum sparsity, as compared with l0 penalty, so l0 penalty is supposed to have superior quality on inverse covariance estimation. This paper introduces a novel time-varying sparse inverse covariance estimation method based on dual l0-penalties (DLP). The new DLP method estimates the sparse inverse covariance by minimizing an l0-penalized log-likelihood function and an extra l0 penalty on temporal homogeneity. A cyclic descent optimization algorithm is further developed to localize the minimum of the objective function. Experiment results on simulated signals show that the proposed DLP method can achieve better performance than conventional l1-penalized methods in estimating time-varying sparse network structures under different scenarios.
{"title":"L0-regularized time-varying sparse inverse covariance estimation for tracking dynamic fMRI brain networks.","authors":"Zening Fu, Sheng Han, Ao Tan, Yiheng Tu, Zhiguo Zhang","doi":"10.1109/EMBC.2015.7318654","DOIUrl":"https://doi.org/10.1109/EMBC.2015.7318654","url":null,"abstract":"Exploration of time-varying functional brain connectivity based on functional Magnetic Resonance Imaging (fMRI) data is important for understanding dynamic brain mechanisms. l1-penalized inverse covariance is a common measure for the inference of sparse structure of functional brain networks, and it has been recently extended to estimate time-varying sparse brain networks by using a sliding window and incorporating a smoothing constraint on temporal variation. However, l1 penalty cannot induce maximum sparsity, as compared with l0 penalty, so l0 penalty is supposed to have superior quality on inverse covariance estimation. This paper introduces a novel time-varying sparse inverse covariance estimation method based on dual l0-penalties (DLP). The new DLP method estimates the sparse inverse covariance by minimizing an l0-penalized log-likelihood function and an extra l0 penalty on temporal homogeneity. A cyclic descent optimization algorithm is further developed to localize the minimum of the objective function. Experiment results on simulated signals show that the proposed DLP method can achieve better performance than conventional l1-penalized methods in estimating time-varying sparse network structures under different scenarios.","PeriodicalId":72689,"journal":{"name":"Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference","volume":"24 1","pages":"1496-9"},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78456150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference
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