A novel single-lead handheld atrial fibrillation detection system

Objective: The single-lead handheld atrial fibrillation (AF) detection device is suitable for daily monitoring or early screening of AF in the hospital. However, the signal quality and the reliability of AF detection algorithm still need to be improved. This study proposed a novel AF detection system with a user-friendly interaction and a lightweight and accurate AF detection algorithm. Approach: The system consisted of a single-lead handheld electrocardiogram (ECG) device with a novel appearance like a gaming handle and a smartphone terminal embedded with AF detection. After feature optimization, the rule-based multi-feature AF detection algorithm had relatively good AF detection ability. Three types of experiments were designed to test the performance of the system. 1) Test the accuracy and time/memory cost of the AF detection algorithm. 2) Compare the proposed device with the standard device Shimmer. 3) Use the simulator to test the effectiveness of the system. Main results: The percentage of differences of successive RR intervals larger than 50 ms (PNN50), minimum value of RR intervals (minRR), and coefficient of sample entropy (COSEn) were features chosen for AF detection. 1) The sensitivity, specificity, and accuracy were 96.00%, 99.75%, 97.88% on the MIT-BIH AF database, and 98.50%, 94.50%, 96.50% on the clinical database we founded. The time/memory cost of the proposed algorithm was much smaller than that of Support Vector Machine (SVM). 2) The mean correlation coefficient of RR was 0.9950, indicating a high degree of consistency. 3) This system showed the effectiveness of AF detection. Significance: The proposed single-lead handheld AF detection system is demonstrated to be accurate, lightweight, consistent with the standard device, and efficient for AF detection.

Validity and Reliability of Micro-controller based BIA Instrument for Assessment of Upper and Lower limb in Male Subjects at Multi-Frequency

The purpose of this study was to validate the resultant data for assessment of upper and lower limb for male subjects, using developed microcontroller based bioelectrical impedance analysis (BIA) instrument with standard device (Microprocessor based 4 channel auto mode T.E.N.S unit) at multi-frequency. Twenty-two male subjects of age 21-45 years were taken under the examination. Data measured by developed BIA instrument is validated with data recorded by standard device. The recorded data represent that the measured data varies with frequencies. The frequencies used for the measurement were 5 KHz, 50 KHz, 100 KHz, 250 KHz, and 500 KHz. The results indicates that impedance of upper and lower limb change according to the frequency variations, and reduces with the increment of the different frequencies. A result also indicates that impedance of the left limb is greater than the impedance of the right limb. The results analysis of upper limb shows that error percentage between developed BIA instrument and standard device is less than 1.93Ω for left arm and less than 1.50Ω for the right arm at the same frequencies. The result analysis of lower limb shows that mean error percentage between both instruments, for left leg is less than 3.37Ω and less than 2.78Ω for right leg.

What does complete digital workflow mean for dentistry?

The introduction of computer-aided manufacturing technologies and further developments have changed the routine workflow in dentistry, and dentists are now rapidly shifting from conventional to digital. As a result, intra-oral scanners have become a standard device in dental clinics even though they have a considerable cost. One of the important reasons of this digital transition is to ensure standardized-quality manufacturing with a shorter chair time, which is promised by complete digital workflow. So, what does complete digital workflow mean for dentistry? This review elaborately answers to this question and summarizes the stages of complete digital workflow in dental applications.

Characteristics improvement of pressure transfer standard using a silicon resonant sensor

<p>In the field of pressure measurement, numerous interlaboratory comparisons are carried out among National Metrology Institutes (NMIs) using a pressure transfer standard to verify the degrees of equivalence. Here, the Yokogawa electric corporation has been producing a series of digital manometers using a silicon resonant sensor developed independently. This sensor demonstrates excellent long-term stability and has thus been adopted as the pressure transfer standard by many NMIs and has been subsequently well received. The pressure transfer standard is known as the resonant silicon gauge (RSG) among NMIs. From December 2016, the National Metrology Institute of Japan (NMIJ), the Advanced Industrial Science and Technology (AIST) institute, and Yokogawa initiated a collaborative research with the aim of improving the characteristics of the RSGs and developing a portable transfer standard using a new silicon resonant sensor. The new RSG was adjusted using a standard device calibrated by either NMIJ or Yokogawa. The measurement values of the standard device were corrected with the calibration results and used as the standard values for adjustment of the new RSG. The linearity of the new RSG adjusted via the proposed method was improved compared with that of a conventional RSG.</p>

Design and uncertainty analysis of field service gas flow standard device based on standard meter method

This paper introduces the composition and working principle of field service gas flow standard device based on standard meter. Through the analysis of the uncertainty of the device and the verification of the measurement results, it is confirmed that the field service standard meter method gas flow standard device can be applied to the verification of the field gas flowmeter.