Showing 49–60 of 161 results

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    A novel neural interfacing electrode array for electrical stimulation and simultaneous recording of EEG/EMG/ENG

    Open Access

    Abstract: Neural interface is man-made information pathway through which biological nerve system could communicate directly with electromechanical devices including computer, robot and even cyborg. This paper introduces a novel neural interfacing electrode array capable of bidirectional information transmission and multi-signals recording. The novel flexible electrode array with 32 channels enables close-looped control and feedback neural interfacing researches with the capability of both electrical stimulation and simultaneous recording of electroencephalogram (EEG), electromyogram (EMG), electroneurogram (ENG) signals. The electrochemical impedance spectroscopy (EIS) measurement of the electrode array was carried out to evaluate the electrode array electrochemical performance in the electrophysiology frequency range. Electrical stimulation to peripheral nerve was performed with various stimulation configuration of ENG electrode site pairs to produce distinct activation patterns. Muscle action potentials of the gastrocnemius of the hind limb indicated different configuration of electrode site pairs could generate distinct stimulating effect. In addition, three groups of in vivo experiments were conducted to demonstrate the recording ability of the electrode array for nerve signals. The data from 32 channels verified the effectiveness of this flexible electrode array in simultaneous recording of EEG/EMG/ENG in vivo.

  • Construction of a focused ultrasound neuromodulation system for the treatment of epileptic seizure

    Open Access

    Abstract: Thus far, Ultrasound has been proved to be useful for noninvasively stimulating brain activity and has hope to play a positive role in the treatment of neurological diseases. Epilepsy is a neurological disorder in which brain activity becomes abnormal, causing seizures or periods of unusual behavior, and sometimes loss of awareness. In this paper, we established a focused ultrasound (FUS) neuromodulation system for the treatment of epilepsy. We used the chemically-induced rat epilepsy model to explore the effect of pulsed focused ultrasound on epilepsy, and obtained preliminary experimental results. We have proved the feasibility of this system through experiments, which can be used in the treatment of epilepsy by ultrasound neuromodulation.

  • Model for Non-contact Blood Pressure Measurement Using the Facial Feature Amount based on Amplitude and Phase Analysis

    Open Access

    Abstract:  To monitor the daily blood pressure, developing a non-contact method for measuring blood pressure is necessary. In a previous study, we proposed a novel method that described the vascular structure of an entire human face as an electric circuit based on amplitude and phase analyses using visible and thermal images of the face. However, the model developed by that method did not consider the order of blood flow because the model applied at random the extracted features. In the present study, it considers a model that incorporates the order of blood flow utilizing amplitude and phase analyses. As a result, the estimated accuracy is improved by considering the order of blood flow. Higher accuracy requires more detailed vascular structure information of the face. It concluded that the facial feature, which is related to the blood pressure, can be obtained by the CEOF analysis.

  • Construction of an individual model for estimating blood pressure using independent components of facial skin temperature considering time variation

    Open Access

    Abstract:  The objective of this study was to construct an individual model for estimating blood pressure (BP) using independent components of facial skin temperature considering time variation. In our previous study, an individual model was constructed for estimating BP by applying independent component analysis to facial skin temperature of each subject. However, in this previous study, time variations in facial skin temperature were not considered. Facial skin temperature is assumed to be related to blood flow over time as blood helps in transporting heat in the body. Therefore, the accuracy of the BP estimation model can be expected to improve if the variation of facial skin temperature caused by blood flow over time considered in addition to only the facial skin temperature. Consequently, the accuracy of the proposed model with the aforementioned considerations was found to be better than that of without these considerations. Therefore, the BP was accurately estimated using the proposed approach.  

  • Research on Gesture Based on GA – SVM

    Open Access

    Abstract:  Surface electromyography (sEMG) is a kind of weak electrical signal generated by muscle activity, which contains information of gesture and is widely used in prosthetic control, rehabilitation and medical treatment. The difference between different motion patterns can be reflected by the different sEMG characteristics, so the recognition of human motion can be studied. Four time-domain features including absolute mean value, waveform length, zero-crossing number and root mean square value were extracted from the double Myo arm-ring data set in Ninapro benchmark database. Classification and identification were performed by using the Support Vector Machine (SVM) optimized by Genetic Algorithms (GA). Experimental results showed that the optimized SVM classification had a better effect.

  • Effects of Daily Life Behavior with a Secondary Task on Performance and Psychophysiological States

    Open Access

    Abstract: The objective of this study was to evaluate the effect of daily life behavior with a secondary task on performance and psychophysiological states. The experiments were based on two conditions: dishwashing (Control) only, and dishwashing while listening to favorite music (Favorite). In the present study, statistical evaluation was conducted to assess the performance and psychophysiological states between the Control and Favorite conditions. As a result, the electromyogram of the ulnar flexor muscle of the wrist in the dominant hand, which is a performance index, showed significant differences between the two conditions. The R-R Interval, which is the physiological index, showed no significant differences between the two conditions. Additionally, the impression of the feelings, which is the psychological index in the Favorite condition were higher than those in the Control condition. Therefore, it is suggested that there is a psychological change as a primary effect of listening to favorite music during daily life behavior, and the performance may be improved as a secondary effect of the psychological change. In conclusion, listening to favorite music decreased the mental fatigue, which is associated with the subjective feelings.

  • Usability Evaluation of Main Function on Three Mobile Banking Application

    Open Access

    Abstract:  E-banking or electronic banking is used to facilitate the bank customers when conducting financial transaction in easy and convinient way. As one of the e-banking form, Mobile banking (m-banking) is a banking service that allows its customers to conduct financial transactions in real time using mobile devices such as smartphones or tablets. Although there is an increasing number of mobile banking service users every year in Indonesia, the utilization of the actual mobile banking apps is still very low compared to other country in Asia. One of the problems that is often encountered by mobile banking’s customers is the aspect of trust that can be influenced by interface and usability of mobile banking applications. Therefore, in order to achieve effective interaction between human-computers with minimal effort, various aspects of usability need to be the main focus in developing an application to support the effectiveness of human-computer interaction so that the initial goal of creating mobile banking to facilitate customer banking transactions can be achieved. Using four criteria of usability mesurement set by ISO, this research aim to evaluate three m-banking application from the largest bank in Indonesia which are Mandiri Mobile, BNI Mobile, and BCA Mobile. Evaluation and analysis from this research shows that BNI Mobile has the best usability among the other two application. Overall, the three mobile banking have quite good usability although there are still several aspects that need to be improved.

    Keywords: ergonomics, usability, mobile banking, SUS, PSSUQ

  • An l1-l1-norm minimization solution using ADMM with FISTA

    Open Access

    Abstract:  This paper discusses compressed sensing which reconstructs original sparse signal from observed data. Our approach formulates the weighted sum of l1-norm error and l1-norm regularization terms, and applies Alternating Direction Method of Multipliers (ADMM) to solve it. Many works employ ADMM for the l1l1-norm minimization problems, where ADMM obtains solutions in an iterative fashion for the problems formed as an augmented Lagrangian. The ADMM process is divided into three steps: an error minimization, a coefficient-norm minimization, and a dual variable update of an augmented  Lagrangian. However, the coefficient-minimization step is not clear and replaced with an approximation. Our contribution is to adopt the Fast Iterative Shrinkage-Thresholding Algorithm (FISTA) for the minimization step and achieves faster implementation than a conventional method. 

    Keywords: Compressed sensing; First Iterative Shrinkage-Thresholding Algorithm (FISTA); Alternating Direction Method of Multipliers (ADMM)

  • Coefficient Constraint LIC with ADMM

    Open Access

    Abstract: Local Intensity Compensation (LIC) is an intra-frame motion compensation for video coding, and was a candidate for HEVC. LIC compensates a target block using motion vectors of reference blocks and linear coefficients of the blocks; thus, from a view point of data compression, not only compensation error but also the range of the motion vectors and coefficients should be as small as possible. Our previous work employs Alternating Direction Method of Multipliers (ADMM) to obtain reference blocks and their coefficients of LIC. This paper proposes to limit the range of coefficients, and experimental results tell us that the proposed method shows almost equivalent compensation accuracy to the conventional method.


    Keywords: Convex Optimization; Alternating Direction Method of Multiply;  norm regularization

  • User Experience Evaluation on the Cryptocurrency Website by Trust Aspect

    Open Access

    Abstract:  A portal into the public ledger cryptocurrency makes a competition of the best web sites and easily trusted by the public. These are believed to constitute a measurable dimensions of User Experience (UX). This study aims to evaluate the user experience of the use of the three web sites most frequently accessed cryptocurrency from Indonesia. The evaluation conducted aimed at knowing the factors that influence user trust through the design of the interface and can be installed on a new design. Methods include Performance Metrics, Post-Task Rating, Post-Session Rating, and Experiential Overview and eye-tracking device. Based on the results of research, in the overall evaluation of the web site, the web site is the most superior of Indodax. The results of the evaluation are then applied on a new design using the software Invision and examined again to see a comparison of the respondent at the time of first use. The result of the research is the assessment, recommendations, and design the look of the web site cryptocurrency are trustworthy based on user experience


    Keywords: Cognitive Ergonomics, Human-Computer Interaction, User Experience, Cryptocurrency, Website, Emotional Design, Online Design

  • Linear Active Disturbance Rejection Control Using Plant Inverse Property

    Open Access

    Abstract:  In this paper, we propose a control law in a linear active disturbance rejection control (LADRC) for removal of ramp disturbance. We use plant inverse characteristics as a control law. We calculate the steady-state error of the conventional method and that of the proposed method using the final-value theorem. In a conventional and a proposed LADRC, each plant output has no steady-state error when a step signal is assumed as a plant input-side disturbance. However, in a conventional LADRC, the plant output has a steady-state error when a ramp signal is assumed as a plant input-side disturbance. On the other hand, in a proposed method, the plant output has no steady-state error. In comparison with a conventional method, the proposed method has almost the same control performance for a plant with a modeling error.

    Keywords: Active disturbance rejection control. Extended state observer. Steady-state error. Plant inverse characteristics.

  • Image Segmentation-Based Face Tracking on Thermal Images for Automatic Estimation of Psychophysiological States Using Facial Skin Temperature Distribution

    Open Access

    Abstract:  In human-machine system, human and machine need to recognize each other’s state with continuously, quantitatively and real-time property. Facial skin temperature could be measured with these properties by infrared thermography. The non-contact property is a great advantage in bioinstrumentation. Previous studies have been reported the availability of facial skin temperature for evaluation of psychophysiological states of a human such as stress, drowsiness and emotion. On the other hand, the development of the face detection and tracking techniques on thermal images are necessary for the automatic evaluation of psychophysiological states of a human based on facial skin temperature, measured by infrared thermography. The objective of this study is to establish the technique for face detection and tracking on thermal images. In this study, the algorithm consisting of three phases: (A) human detection based on inter-frame difference, (B) face detection based on image segmentation, and (C) face tracking based on temporal analysis, is proposed. As a result, the face region on thermal images could be detected and tracked with high precision. However, a part with low temperature such as the back of nasal and cheek was classified as a region other than a face.


    Keywords: Thermal image; face tracking; image segmentation