1.Study of emotion recognition under anxiety based on physiological signals by relief method.
Pei LEI ; Jing WANG ; Xinwei ZHOU ; Xinyu CHAI
Chinese Journal of Medical Instrumentation 2014;38(3):186-189
Anxiety is usually generated because of the threatened feeling. The data of electrocardio, respiration, blood volume pulse and skin conductance signals were collected. The arithmetic of Relief were used for the feature selection and combined with k-Nearest Neighbor (kNN) arithmetic and Support Vector Machine (SVM) arithmetic for classification. The results show that the combination of Relief-SVM is better than combination of Relief-kNN on the recognition of anxiety state. The emotion recognition based on multi-physiological signals is superior to that based on one single signal.
Algorithms
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Anxiety
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Artificial Intelligence
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Humans
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Pattern Recognition, Automated
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Support Vector Machine
2.Design and optimization of wireless power and data transmission for visual prosthesis.
Xuping LEI ; Kaijie WU ; Lei ZHAO ; Xinyu CHAI
Chinese Journal of Medical Instrumentation 2013;37(6):427-431
Boosting spatial resolution of visual prostheses is an effective method to improve implant subjects' visual perception. However, power consumption of visual implants greatly rises with the increasing number of implanted electrodes. In respond to this trend, visual prostheses need to develop high-efficiency wireless power transmission and high-speed data transmission. This paper presents a review of current research progress on wireless power and data transmission for visual prostheses, analyzes relative principles and requirement, and introduces design methods of power and data transmission.
Electric Power Supplies
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Prosthesis Design
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Visual Prosthesis
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Wireless Technology
3.The research on high-density flexible microelectrode array of retinal prosthesis based on MEMS technology.
Gang FENG ; Xiaohong SUI ; Yu WANG ; Gang LI ; Xinyu CHAI
Chinese Journal of Medical Instrumentation 2013;37(6):407-410
The paper proposed a new method to design and fabricate a flexible neural microelectrode arrays (MEA) for retinal prosthesis, the ion-beam technology was introduced to decrease the width of conductive wires and the distances between wires, a high density MEA (120 microelectrodes with a matrix of 10 x 12) was fabricated on a single layer of polymer from this. The MEA was proved to possess a fine electrochemical property. In vitro test, the average impedance of MEA on 1 kHz was 16 k omega +/- 2 k omega and the average phase difference was -85 degrees +/-30 degrees.
Micro-Electrical-Mechanical Systems
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Microelectrodes
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Prosthesis Design
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Visual Prosthesis
4.Clinical study of Wingspan stents for symptomatic atherosclerotic stenosis of the basilar artery
Yuan CHAI ; Lili CHAI ; Tao ZHANG ; Hu CHEN ; Xinyu LI ; Wei MA ; Lili JING ; Jianping DENG ; Zhenwei ZHAO ; Guodong GAO
Journal of Practical Radiology 2014;(6):1003-1006,1025
Objective To assess the efficacy and feasibility of Wingspan stents for symptomatic atherosclerotic stenosis of the bas-ilar artery.Methods Clinical data of 40 patients with symptomatic atherosclerotic stenoses in the basilar artery were analyzed retro-spectively.The operative successful rate,the degree of stenosis,perioperative complications and the results of clinical and imaging follow-up were analyzed.Results The technical success rate was 95.35%.The rate of procedure-related complications during the perioperative period (30 days)was 20.0% (eight of 40 patients).There were two patients with no permanent neurological sequelae. Ipsilateral stroke or death occurred in six patients(1 5%).Thirty-six patients(92.3%)were available for a clinical follow up.The mean follow-up period was 36.3 months (range 12-75 months).Seventeen patients (47.2%)were available for follow-up imaging with DSA or CTA.The mean imaging follow-up period was 9.4 months (range 4-41 months).Symptomatic in-stent restenosis (ISR)was documented in two (1 1.76%)of these patients.Three ischemic events occurred during the follow-up period in 12 months.The adverse event rate was 8.33% at 1 year.Conclusion Wingspan stents for symptomatic atherosclerotic stenosis of the basilar artery was an effective and feasible technique,but we should carefully grasp the operation indications.
5.Recognition of Chinese character on electrotactile vision substitution system.
Jie LIU ; Zhumao ZHANG ; Qiushi REN ; Xinyu CHAI
Chinese Journal of Medical Instrumentation 2010;34(5):313-316
In this paper, we used the eletrotactile vision substitution system designed by ourselves to display Chinese characters on the 16x16 electrode array through some simple image processing algorithms and multiplexing technology. Based on this, simple Chinese character recognition experiment was conducted. The result of the experiment shows that the electrotactile vision substitution is a feasible solution for the blind to read simple Chinese characters and the result also solidifies the foundation of further study about more complex real-time image electrotactile display.
Algorithms
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Communication Aids for Disabled
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Image Processing, Computer-Assisted
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Language
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Touch
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Vision, Ocular
6.The research progress of mobility performance in simulated prosthetic vision.
Liujun GU ; Jing WANG ; Yanyu LU ; Xinyu CHAI
Chinese Journal of Medical Instrumentation 2012;36(2):110-113
This paper introduces the current research progress on effect factors of mobility performance based on simulated prosthetic vision.
Phosphenes
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Prostheses and Implants
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Vision, Ocular
7.Image processing system of visual prostheses based on digital signal processor DM642.
Chengcheng XIE ; Yanyu LU ; Yun GU ; Jing WANG ; Xinyu CHAI
Chinese Journal of Medical Instrumentation 2011;35(5):330-334
This paper employed a DSP platform to create the real-time and portable image processing system, and introduced a series of commonly used algorithms for visual prostheses. The results of performance evaluation revealed that this platform could afford image processing algorithms to be executed in real time.
Algorithms
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Image Processing, Computer-Assisted
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instrumentation
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methods
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Signal Processing, Computer-Assisted
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instrumentation
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Visual Prosthesis
8.Optimum design and performance evaluation of down-sampling algorithm for visual prosthesis imaging processing.
Yun GU ; Kaijie WU ; Xuping LEI ; Hao WU ; Xinyu CHAI
Chinese Journal of Medical Instrumentation 2013;37(1):33-36
According to analyses of the real-time performance of the visual prosthesis image processing system, down-sampling is a key factor which influences the processing speed. Based on these analyses, the algorithm of grid sampled averaging was proposed for down-sampling. Then the effect of grid parameters on the result and algorithm complexity was evaluated by using the regional-averaging algorithm as a reference. Our research shows that the grid-averaging algorithm could reduce the computation burden by 90% or more, with no significant difference from the regional-averaging algorithm.
Algorithms
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Image Processing, Computer-Assisted
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methods
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Visual Prosthesis
9.In-vitro electrochemical stability evaluation of a flexible MEMS microelectrode.
Yu WANG ; Xiaohong SUI ; Gang FENG ; Gang LI ; Xinyu CHAI
Chinese Journal of Medical Instrumentation 2013;37(1):6-9
Three-electrode testing method was used to investigate the effect of temperature on electrode impedance, and the pH shifts in saline solution resulting from the electrical stimulation were also determined. Experiments in PBS (phosphate buffered solution) solution showed that the electrode impedance was almost invariable at the human body temperature range (35 degrees C-40 degrees C). And the experiments in unbuffered saline solution showed that pH shifts decreased from 0.03 to 0.005 when the frequency of biphasic charged-balanced pulses increased from 1 Hz to 100 Hz. Even stimulated by monophasic pulses (frequency is 15 Hz, amplitude is 50 microA), the stimulus-induced pH shift of electrode only varies 0.15 (anodic pulse current increased 0.15 and cathodic pulse current decreased 0.15).
Electrochemistry
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Eye, Artificial
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Materials Testing
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Microelectrodes
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Prostheses and Implants
10.An integrated system of blood pressure measurement with bluetooth communication.
Wei WANG ; Jing WANG ; Hongyang SUN ; Zuyang XU ; Xinyu CHAI
Chinese Journal of Medical Instrumentation 2012;36(4):239-243
The development of the integrated blood pressure system with bluetooth communication function is introduced. Experimental results show that the system can complete blood pressure measurement and data transmission wireless effectively, which can be used in m-Health in future.
Blood Pressure Determination
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instrumentation
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methods
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Humans
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Telemetry
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instrumentation