{"title":"High Frequency Oscillations Detection in Patients Combining Wavelet Decomposition and Back Propagation Neural Network*","authors":"Dakun Lai, Zenghui Kan, Wenjing Chen, Heng Zhang","doi":"10.1109/BIOCAS.2018.8584770","DOIUrl":"https://doi.org/10.1109/BIOCAS.2018.8584770","url":null,"abstract":"Localization of epileptic focus is a worldwide problem. Many studies find that high frequency oscillations (HFOs) seem to be a very specific indicator of the seizure onset zone (SOZ) in recent years. However, it is hard to detect HFOs accurately and many algorithms have a high sensitivity but unsatisfactory specificity. In this study, a novel method combining wavelet decomposition and back propagation (BP) neural network was proposed to increase the specificity of HFOs detection. Three epileptic patients with medically intractable epilepsy were recruited and underwent an individually presurgical monitoring with around 54–90 channels of intracranial electroencephalograph (iEEG). Over 3970 analyzed HFOs events from 420 hours of iEEG data, the sensitivity and the false discovery rate (FDR) of the present approach were 90% and 8.50%, respectively. The obtained results showed that the proposed BP neural network combined with wavelet decomposition could obviously decrease the influence of spikes and high-frequency noise caused by patient motion, which both are similar to HFOs, meanwhile effectively improve the specificity of HFOs detection.","PeriodicalId":259162,"journal":{"name":"2018 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121958171","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}
{"title":"A Half-Shared Transimpedance Amplifier Architecture for High-throughput CMOS Bioelectronics","authors":"Geoffrey Mulberry, Kevin A. White, Brian N. Kim","doi":"10.1109/BIOCAS.2018.8584792","DOIUrl":"https://doi.org/10.1109/BIOCAS.2018.8584792","url":null,"abstract":"A common problem in single-cell measurement is the low-throughput nature of measurements. Monolithic CMOS microsystems have enabled many parallel measurements to take place simultaneously to increase throughput due to the integration of electrodes and amplifiers into a single chip. This paper explores a CMOS chip containing an array of 1024 parallel transimpedance amplifiers that takes advantage of a “half-shared” operational amplifier architecture. This architecture splits a traditional 5-transistor operational amplifier into two, the inverting half and the non-inverting half. Splitting an amplifier into two allows for the non-inverting half to be “shared” with several inverting halves, reducing the die area required for each individual amplifier. This allows for an increased number of amplifiers to be embedded into the same chip; in this case, 32 amplifiers are able to fit in the same space as 17 traditional 5-transistor operational amplifiers. The amplifiers exhibit low mismatch of 1.65 mV across the entire 1024 amplifier array, as well as high linearity in transimpedance gain. The technique will enable larger arrays to be created in future designs to allow electrophysiologists, among others, access to even higher-throughput measurement tools.","PeriodicalId":259162,"journal":{"name":"2018 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127944905","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}
{"title":"Design and Custom Fabrication of a Smart Temperature Sensor for an Organ-on-a-chip Platform","authors":"R. Ponte, V. Giagka, W. Serdijn","doi":"10.1109/BIOCAS.2018.8584834","DOIUrl":"https://doi.org/10.1109/BIOCAS.2018.8584834","url":null,"abstract":"This paper reports on the design and fabrication of a time-mode signal-processing in situ temperature sensor customized for an organ-on-a-chip (OOC) application. The circuit was fabricated using an in-house integrated circuit (IC) technology that requires only seven lithographic steps and is compatible with MEMS fabrication process. The proposed circuit is developed to provide the first out-of-incubator temperature monitoring of cell cultures on an OOC platform in a monolithic fabrication. Measurement results on wafer reveal a temperature measurement resolution of less than ±0.2 °C (3σ) and a maximum nonlinearity error of less than 0.3% across a temperature range from 25 °C to 100 °C.","PeriodicalId":259162,"journal":{"name":"2018 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115892345","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}
Andrei Nakagawa Silva, Sai Praneeth Reddy Sunkesula, Anna Prach, J. Cabibihan, N. Thakor, A. Soares
{"title":"Slip suppression in prosthetic hands using a reflective optical sensor and MPI controller","authors":"Andrei Nakagawa Silva, Sai Praneeth Reddy Sunkesula, Anna Prach, J. Cabibihan, N. Thakor, A. Soares","doi":"10.1109/BIOCAS.2018.8584711","DOIUrl":"https://doi.org/10.1109/BIOCAS.2018.8584711","url":null,"abstract":"Prosthetic hands have greatly evolved in mechatronic, robotic and control aspects. However, occasional accidents might happen due to excessive grip force or the breaking of contact due to slip. Fast transient slip events can be properly handled by a low-level controller that can behave like a reflex to maintain grasp stability in a shared control manner between the user and the prosthetic hand itself. Here we propose the use of a reflective optic sensor to capture slip events and evaluate the performance of a monotonic PI (MPI) control law that acts as to suppress slip. We have characterized the response of the sensor to motion and noted that transparent surfaces generate smaller responses. The proof-of-concept experiment demonstrated the effectiveness of the MPI controller where slip events were properly suppressed by an increase in grip force.","PeriodicalId":259162,"journal":{"name":"2018 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"148 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115908618","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}
Christopher L. Hunt, Avinash Sharma, Luke E. Osborn, R. Kaliki, N. Thakor
{"title":"Predictive trajectory estimation during rehabilitative tasks in augmented reality using inertial sensors","authors":"Christopher L. Hunt, Avinash Sharma, Luke E. Osborn, R. Kaliki, N. Thakor","doi":"10.1109/BIOCAS.2018.8584805","DOIUrl":"https://doi.org/10.1109/BIOCAS.2018.8584805","url":null,"abstract":"This paper presents a wireless kinematic tracking framework used for biomechanical analysis during rehabilitative tasks in augmented and virtual reality. The framework uses low-cost inertial measurement units and exploits the rigid connections of the human skeletal system to provide egocentric position estimates of joints to centimeter accuracy. On-board sensor fusion combines information from three-axis accelerometers, gyroscopes, and magnetometers to provide robust estimates in real-time. Sensor precision and accuracy were validated using the root mean square error of estimated joint angles against ground truth goniometer measurements. The sensor network produced a mean estimate accuracy of 2.81° with 1.06° precision, resulting in a maximum hand tracking error of 7.06 cm. As an application, the network is used to collect kinematic information from an unconstrained object manipulation task in augmented reality, from which dynamic movement primitives are extracted to characterize natural task completion in N = 3 able-bodied human subjects. These primitives are then leveraged for trajectory estimation in both a generalized and a subject-specific scheme resulting in 0.187 cm and 0.161 cm regression accuracy, respectively. Our proposed kinematic tracking network is wireless, accurate, and especially useful for predicting voluntary actuation in virtual and augmented reality applications.","PeriodicalId":259162,"journal":{"name":"2018 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"196 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133988493","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}
{"title":"Proto-Object Based Saliency Model with Second-Order Texture Feature","authors":"T. Uejima, E. Niebur, R. Etienne-Cummings","doi":"10.1109/BIOCAS.2018.8584749","DOIUrl":"https://doi.org/10.1109/BIOCAS.2018.8584749","url":null,"abstract":"The nervous system can rapidly select important information from a visual scene and pay attention to it. Bottom-up saliency models use low-level features such as intensity, color, and orientation to generate a saliency map that predicts human fixations. Such algorithms work well for many images, however they miss the influence of texture. In this paper, we add a second-order texture channel to a proto-object based saliency model. The extended model shows significantly improved performance in predicting human fixations.","PeriodicalId":259162,"journal":{"name":"2018 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130916903","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}
{"title":"Missing Structural and Clinical Features Imputation for Semi-supervised Alzheimer's Disease Classification using Stacked Sparse Autoencoder","authors":"Emimal Jabason, M. Ahmad, M. Swamy","doi":"10.1109/BIOCAS.2018.8584844","DOIUrl":"https://doi.org/10.1109/BIOCAS.2018.8584844","url":null,"abstract":"In recent years, the accurate detection of Alzheimer's disease (AD) at its early stage, using various biomarkers through machine learning techniques, has been given paramount importance in the medical field. However, in reality, the input datasets contain lots of missing values due to several factors such as increasing mortality rate, avoiding invasive procedures, and dropping out from the study. In this work, after analyzing the pattern of structural and clinical data from tadpole study in Alzheimer's disease neuroimaging initiative (ADNI) database, it has been found that the unobserved data are not missing completely at random. In view of this fact, with the assumption that the missing data patterns are in blocks, we propose a novel stacked sparse autoencoder based method to assign a value in the missing places and to select the significant structural and clinical features in order to discriminate the patients having AD, mild cognitive impairment (MCI), and cognitively normal (CN) clinical status. Through experimental results, it is shown that the proposed imputation algorithm achieves better performance for semi-supervised AD classification in terms of accuracy, sensitivity, and specificity in 5-fold cross validation when compared to the state-of-the-art methods.","PeriodicalId":259162,"journal":{"name":"2018 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"182 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133549810","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}
{"title":"An Efficient Hardware Architecture Design of EEMD Processor for Electrocardiography Signal","authors":"I-Wei Chen, Shang-Yi Chuang, W. Wu, W. Fang","doi":"10.1109/BIOCAS.2018.8584764","DOIUrl":"https://doi.org/10.1109/BIOCAS.2018.8584764","url":null,"abstract":"This study proposed an efficient hardware architecture design of Ensemble Empirical Mode Decomposition (EEMD) processor for the signal analysis of Electrocardiography (ECG). The proposed processor is implemented in an on-board Xilinx FPGA for on-line signal processing of the non-linear and non-stationary signal. The EEMD method is appropriate to analyze the non-linear ECG signal with assisting white noise and decompose the signal into 8 sets of Intrinsic Mode Functions (IMFs). The experimental result shows that the mode mixing problem, which exists in the Empirical Mode Decomposition (EMD) method, solved by the proposed EEMD processor. The study solves the obstacle of mode mixing and achieves high accuracy with data error < 4.7×10-5. This approach can effectively analyze the non-linear and non-stationary biomedical signal and facilitate cardiovascular diseases diagnosis and long-term monitoring.","PeriodicalId":259162,"journal":{"name":"2018 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115754227","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}
Li Jing Ong, Shih-Chiang Liu, Marshal Dian Sheng Wong, Tafadzwa Sibindi, G. Gammad, C. Tsai, Astrid Rusly, K. Ng, C. Libedinsky, S. Nag, S. Yen
{"title":"A Fully Wireless Implantable Multi-Channel Muscle Stimulator with Closed-Loop Feedback Control","authors":"Li Jing Ong, Shih-Chiang Liu, Marshal Dian Sheng Wong, Tafadzwa Sibindi, G. Gammad, C. Tsai, Astrid Rusly, K. Ng, C. Libedinsky, S. Nag, S. Yen","doi":"10.1109/BIOCAS.2018.8584753","DOIUrl":"https://doi.org/10.1109/BIOCAS.2018.8584753","url":null,"abstract":"We have developed an implantable four-channel high-current biphasic stimulator device for controlling the muscles of the hand, and successfully tested it in a non-human primate (NHP). The charge-balanced stimulator features an external unit which connects to a personal computer via WiFi, and provides wireless power and data control commands to the implant across biological tissue. The stimulator obtained realtime grip force from the hand using a force sensor to perform automated closed-loop control of the stimulation amplitude to ensure that we were able to produce sustained gripping force in the hand of the animal in the event of muscle fatigue. The device was encapsulated using a FDA-compliant biocompatible polymer for reliable long-term study. In-vivo experiments performed after the stimulator (with electrodes embedded in different muscles) had been implanted for one month demonstrated that the system was able to evoke, and automatically maintain, a targeted range of gripping force in the animal's hand. Our results demonstrate the utility of our closed-loop muscle stimulator as a neuroprosthesis for restoring functional hand movements in patients with upper-limb peripheral nerve injuries.","PeriodicalId":259162,"journal":{"name":"2018 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124205657","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}
Surabhi Kalyan, Siddharth Joshi, Sadique Sheik, B. Pedroni, Gert Cauwcnbcrghs
{"title":"Unsupervised Synaptic Pruning Strategies for Restricted Boltzmann Machines","authors":"Surabhi Kalyan, Siddharth Joshi, Sadique Sheik, B. Pedroni, Gert Cauwcnbcrghs","doi":"10.1109/BIOCAS.2018.8584839","DOIUrl":"https://doi.org/10.1109/BIOCAS.2018.8584839","url":null,"abstract":"While unsupervised generative neural networks are attractive choices for adoption in always-on continuous-time smart sensory systems, they typically impose heavy memory requirements on the underlying computational fabric. Recent literature on binarized neural networks has not yet been extended to unsupervised generative networks and alternate strategies are required to reduce their memory footprint. This work studies unsupervised synaptic pruning strategies to reduce the memory requirements for Restricted Boltzmann Machines (RBMs). In addition to one-shot pruning, we explore alternative strategies that encompass iterative stochastic pruning as well as pruning under target probability density functions for an RBM trained over the MNIST database. Interestingly, the results presented here suggest that one-shot re-training after pruning of the least significant connections in a trained network yields improved per-formance/memory trade-off over multiple iterations of stochastic pruning and re-training on the same network.","PeriodicalId":259162,"journal":{"name":"2018 IEEE Biomedical Circuits and Systems Conference (BioCAS)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124364804","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}