scholarly journals An evolutionary approach to continuously estimate CPR quality parameters from a wrist-worn inertial sensor

2021 ◽  
Author(s):  
Christian Lins ◽  
Björn Friedrich ◽  
Andreas Hein ◽  
Sebastian Fudickar
Keyword(s):  
Inertial Sensor ◽  
Sudden Cardiac Arrest ◽  
Model Fitting ◽  
Quality Parameters ◽  
Measurement Unit ◽  
Suitable Alternative ◽  
Fitting Method ◽  
Emergency Interventions ◽  
Cpr Quality ◽  
Cpr Training

AbstractCardiopulmonary resuscitation (CPR) is one of the most critical emergency interventions for sudden cardiac arrest. In this paper, a robust sinusoidal model-fitting method based on a Evolution Strategy inspired algorithm for CPR quality parameters – naming chest compression frequency and depth – as measured by an inertial measurement unit (IMU) attached to the wrist is presented. The proposed approach will allow bystanders to improve CPR as part of a continuous closed-loop support system once integrated into a smartphone or smartwatch application. By evaluating the model’s precision with data recorded by a training mannequin as reference standard, a variance for the compression frequency of $$\pm 2.22$$ ± 2.22 compressions per minute (cpm) has been found for the IMU attached to the wrist. It was found that this previously unconsidered position and thus, the use of smartwatches is a suitable alternative to the typical placement of phones in hand for CPR training.

scholarly journals Fique as a Sustainable Material and Thermal Insulation for Buildings: Study of Its Decomposition and Thermal Conductivity

2021 ◽  
Vol 13 (13) ◽  
pp. 7484
Author(s):  
Gabriel Fernando García Sánchez ◽  
Rolando Enrique Guzmán López ◽  
Roberto Alonso Gonzalez-Lezcano
Keyword(s):  
Thermal Conductivity ◽  
Thermal Decomposition ◽  
Thermal Insulation ◽  
Model Fitting ◽  
Good Alternative ◽  
Negative Effects ◽  
Thermal Insulator ◽  
Fitting Method ◽  
Thermogravimetric Data ◽  
Reduce Energy Consumption

Buildings consume a large amount of energy during all stages of their life cycle. One of the most efficient ways to reduce their consumption is to use thermal insulation materials; however, these generally have negative effects on the environment and human health. Bio-insulations are presented as a good alternative solution to this problem, thus motivating the study of the properties of natural or recycled materials that could reduce energy consumption in buildings. Fique is a very important crop in Colombia. In order to contribute to our knowledge of the properties of its fibers as a thermal insulator, the measurement of its thermal conductivity is reported herein, employing equipment designed according to the ASTM C 177 standard and a kinetic study of its thermal decomposition from thermogravimetric data through the Coats–Redfern model-fitting method.

An Improved and Efficient Algorithm for SINS/GPS/Doppler Integrated Navigation Systems

2012 ◽  
Vol 245 ◽  
pp. 323-329 ◽  
Author(s):  
Muhammad Ushaq ◽  
Jian Cheng Fang
Keyword(s):  
Kalman Filter ◽  
Navigation System ◽  
Inertial Navigation System ◽  
Inertial Sensor ◽  
Inertial Navigation ◽  
Measurement Unit ◽  
Navigation Systems ◽  
Integrated Navigation ◽  
Efficient Manner ◽  
Position Errors

Inertial navigation systems exhibit position errors that tend to grow with time in an unbounded mode. This degradation is due, in part, to errors in the initialization of the inertial measurement unit and inertial sensor imperfections such as accelerometer biases and gyroscope drifts. Mitigation to this growth and bounding the errors is to update the inertial navigation system periodically with external position (and/or velocity, attitude) fixes. The synergistic effect is obtained through external measurements updating the inertial navigation system using Kalman filter algorithm. It is a natural requirement that the inertial data and data from the external aids be combined in an optimal and efficient manner. In this paper an efficient method for integration of Strapdown Inertia Navigation System (SINS), Global Positioning System (GPS) and Doppler radar is presented using a centralized linear Kalman filter by treating vector measurements with uncorrelated errors as scalars. Two main advantages have been obtained with this improved scheme. First is the reduced computation time as the number of arithmetic computation required for processing a vector as successive scalar measurements is significantly less than the corresponding number of operations for vector measurement processing. Second advantage is the improved numerical accuracy as avoiding matrix inversion in the implementation of covariance equations improves the robustness of the covariance computations against round off errors.

scholarly journals The Use of the Dynamics of Changes in Table Eggs during Storage to Predict the Age of Eggs Based on Selected Quality Traits

Animals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 3192
Author(s):  
Kamil Drabik ◽  
Tomasz Próchniak ◽  
Kornel Kasperek ◽  
Justyna Batkowska
Keyword(s):  
Polynomial Regression ◽  
Egg Quality ◽  
Model Fitting ◽  
Multiple Linear Regression Model ◽  
Specific Weight ◽  
Quality Parameters ◽  
Regression Equations ◽  
Mathematical Methods ◽  
Cage System ◽  
Daily Changes

The aim of the study was to determine daily changes in some egg quality parameters, indirectly reflecting egg freshness, and to assess the possibility of predicting time from laying using mathematical methods. The study material consisted of 365 table eggs of medium (M, ≥53 g and <63 g) and large (L, ≥63 g and <73 g) weight classes (commercial stock, cage system, brown-shelled eggs) collected on the same day. Eggs were numbered individually and placed on transport trays and stored (14 °C, 70% RH). Every day, for 35 days, egg quality characteristics were analyzed (10 eggs per group). The change of traits in time was analyzed on the basis of linear and polynomial regression equations, depending on the trait. Based on model fitting, eight traits were selected as those most affected by storage time: egg weight and specific weight, Haugh units, albumen weight, air cell depth, yolk index, albumen and yolk pH. These traits, excluding those related to the weight, were then used in a multiple linear regression model to predict egg age. All regression models presented in this study were characterized by high predictive efficiency, which was confirmed by comparison of the observed and estimated values.

A new method to reduce the noise of the miniaturised inertial sensors disposed in redundant linear configurations

2013 ◽  
Vol 117 (1188) ◽  
pp. 111-132 ◽  
Author(s):  
T. L. Grigorie ◽  
R. M. Botez
Keyword(s):  
Inertial Sensors ◽  
Inertial Sensor ◽  
Low Frequency ◽  
Minimum Variance ◽  
Measurement Unit ◽  
Time Step ◽  
Accelerometer Sensor ◽  
Sensor Model ◽  
Input Acceleration

Abstract This paper presents a new adaptive algorithm for the statistical filtering of miniaturised inertial sensor noise. The algorithm uses the minimum variance method to perform a best estimate calculation of the accelerations or angular speeds on each of the three axes of an Inertial Measurement Unit (IMU) by using the information from some accelerometers and gyros arrays placed along the IMU axes. Also, the proposed algorithm allows the reduction of both components of the sensors’ noise (long term and short term) by using redundant linear configurations for the sensors dispositions. A numerical simulation is performed to illustrate how the algorithm works, using an accelerometer sensor model and a four-sensor array (unbiased and with different noise densities). Three cases of ideal input acceleration are considered: 1) a null signal; 2) a step signal with a no-null time step; and 3) a low frequency sinusoidal signal. To experimentally validate the proposed algorithm, some bench tests are performed. In this way, two sensors configurations are used: 1) one accelerometers array with four miniaturised sensors (n = 4); and 2) one accelerometers array with nine miniaturised sensors (n = 9). Each of the two configurations are tested for three cases of input accelerations: 0ms−1, 9·80655m/s2 and 9·80655m/s2.

Interpolated local model fitting method for accurate and fast single-shot surface profiling

2009 ◽  
Vol 48 (18) ◽  
pp. 3497 ◽  
Author(s):  
Tatsuya Yokota ◽  
Masashi Sugiyama ◽  
Hidemitsu Ogawa ◽  
Katsuichi Kitagawa ◽  
Kazuyoshi Suzuki
Keyword(s):  
Model Fitting ◽  
Local Model ◽  
Single Shot ◽  
Surface Profiling ◽  
Fitting Method

Is a Head-Worn Inertial Sensor a Valid Tool to Monitor Swimming?

2021 ◽  
pp. 1-4
Author(s):  
Stephanie J. Shell ◽  
Brad Clark ◽  
James R. Broatch ◽  
Katie Slattery ◽  
Shona L. Halson ◽  
...  
Keyword(s):  
Correlation Coefficient ◽  
Video Analysis ◽  
Inertial Sensor ◽  
Absolute Error ◽  
Wearable Device ◽  
Measurement Unit ◽  
Fisher Exact Test ◽  
Mean Velocity ◽  
Video Footage ◽  
Stroke Type

Purpose: This study aimed to independently validate a wearable inertial sensor designed to monitor training and performance metrics in swimmers. Methods: A total of 4 male (21 [4] y, 1 national and 3 international) and 6 female (22 [3] y, 1 national and 5 international) swimmers completed 15 training sessions in an outdoor 50-m pool. Swimmers were fitted with a wearable device (TritonWear, 9-axis inertial measurement unit with triaxial accelerometer, gyroscope, and magnetometer), placed under the swim cap on top of the occipital protuberance. Video footage was captured for each session to establish criterion values. Absolute error, standardized effect, and Pearson correlation coefficient were used to determine the validity of the wearable device against video footage for total swim distance, total stroke count, mean stroke count, and mean velocity. A Fisher exact test was used to analyze the accuracy of stroke-type identification. Results: Total swim distance was underestimated by the device relative to video analysis. Absolute error was consistently higher for total and mean stroke count, and mean velocity, relative to video analysis. Across all sessions, the device incorrectly detected total time spent in backstroke, breaststroke, butterfly, and freestyle by 51% (15%). The device did not detect time spent in drill. Intraclass correlation coefficient results demonstrated excellent intrarater reliability between repeated measures across all swimming metrics. Conclusions: The wearable device investigated in this study does not accurately measure distance, stroke count, and velocity swimming metrics or detect stroke type. Its use as a training monitoring tool in swimming is limited.

Abstract 181: An Analysis of Worldwide Public Access Defibrillator Usage Since October 2012. Does CPR Prior to Defibrillation Improve Survival Outcomes?

Circulation ◽  
2018 ◽  
Vol 138 (Suppl_2) ◽  
Author(s):  
Hannah Torney ◽  
Adam Harvey ◽  
Olibhear McAlister ◽  
Amy Kernaghan ◽  
Laura Davis ◽  
...  
Keyword(s):  
Hospital Admission ◽  
Sudden Cardiac Arrest ◽  
Public Spaces ◽  
Public Access ◽  
Survival Outcomes ◽  
Summary Statistics ◽  
Demographic Information ◽  
Chain Of Survival ◽  
Bystander Cpr ◽  
Cpr Quality

Introduction: As outlined by the Chain of Survival, effective cardiopulmonary resuscitation (CPR) and rapid defibrillation are vital to improve survival from sudden cardiac arrest (SCA). Placement of public access defibrillators (PADs) is becoming more common in public spaces, and they are more frequently used by untrained lay-users. The objective of this analysis was to assess the effect of CPR prior to defibrillation, and the success of PAD usage in terms of first shock success and survival to hospital admission. Methods: This dataset was composed of voluntarily submitted demographic information and electronic PAD files collected from October 2012 - June 2018. Summary statistics were calculated, and proportions were determined with 95% confidence intervals (CI) where appropriate. The association between CPR prior to defibrillation and survival was investigated by fitting a logistical model with survival as the dependent variable and CPR as covariate. Results: A total of 2812 PAD events were analyzed. Mean (SD) patient age was 61 (19) years and males comprised 72.5% (1922 of 2650 events where gender was known) of the events reported. The most common locations of SCA were the home (1039, 36.9%), public (719, 25.6%) and medical facility (328, 11.7%). Median (IQR) time to PAD delivery was 5 (3, 11) minutes. Ventricular fibrillation or tachycardia was present in 1010 (35.9%) patients, and 979 received a shock, with 87.2% (95%CI [85.0%, 89.3%]) achieving first shock success. Of the 849 shockable patients for whom survival was known, 565 (66.5%, (95%CI [63.3%, 69.7%]) survived to hospital admission. Survival outcome was known for 2150 patients, and 681 (31.7%, 95%CI [29.7%, 33.69%]) survived to hospital admission. A total of 1649 (58.6%) SCAs were witnessed and 1293 (78.4%) patients received bystander CPR prior to defibrillation. Bystander CPR prior to defibrillation was significantly associated with survival to hospital admission (OR = 2.17, 95%CI [1.69, 2.81], p<0.001). Conclusion: These results suggest that CPR application prior to application of a PAD significantly increases a patient’s chances of surviving to hospital admission. This study did not assess CPR quality, but it is intuitive that good quality CPR would align with higher survival outcomes.

Abstract 250: Effect of Coaching on Dispatch-assisted Cardiopulmonary Resuscitation: A Randomized Simulation Study

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_4) ◽  
Author(s):  
Hidetada Fukushima ◽  
Keisuke Takano ◽  
Hideki Asai
Keyword(s):  
Cardiopulmonary Resuscitation ◽  
Simulation Study ◽  
Average Rate ◽  
Sudden Cardiac Arrest ◽  
Video Camera ◽  
Guideline Recommendation ◽  
Compression Depth ◽  
Bystander Cardiopulmonary Resuscitation ◽  
Cpr Training ◽  
Study Participants

Introduction: Immediate bystander cardiopulmonary resuscitation (CPR) is essential for the good outcome of sudden cardiac arrest victims. Current guidelines recommend dispatch-assisted CPR (DACPR). Its quality, however, varies from case to case. The aim of this study was todetermine the effectiveness of dispatch coaching on the quality of CPR by lay rescuers. Methods: We conducted a DACPR simulation study. Participants with no prior CPR training within 1 year were assigned randomly to one of two DACPR simulations (No Coaching Group: callers were told to perform CPR and the dispatcher sometimes confirmed if the caller was performing CPR or Coaching Group: the dispatcher coached, encouraged, and counted out loud with a metronome). The study participants performed CPR for 2 minutes under the study dispatcher. All performances were recorded by video camera and Resusci Anne® QCPR (Laerdal, Norway). Results: Forty-nine participants aged 20s to 50s were recruited, and 48 completed the simulation (Coaching Group, 27, 9 males and No Coaching Group, 21, 16 males). The average rate of chest compressions was 102.5/min in Coaching Group and 109.3/min in No Coaching group (p=0.270). The average compression depth was slightly deeper in Coaching group (43.0mm vs 41.5mm, p=0.695). When compared the average depth of the first 10 compressions to the total average in each group, the depth significantly improved in Coaching group while that decreased in No Coaching Groups (38.4mm to 43.0mm; p=0.020, 42.3mm to 41.5mm; p=0.431, respectively). The chest compression fraction was also high in Coaching Group (99.4% vs 93.0%, p=0.005). Conclusions: Participants in Coaching Group performed better CPR compared to No Coaching Group in terms of high flow fraction. Although the average compression depth was below the guideline recommendation in both groups, it significantly improved in Coaching group. This study indicates that dispatch coaching can optimize the performance of bystander CPR.

Study of Zero Velocity Update for Both Low- and High-Speed Human Activities

2012 ◽  
pp. 65-84
Author(s):  
R. Zhang ◽  
M. Loschonsky ◽  
L.M. Reindl
Keyword(s):  
Human Activities ◽  
High Speed ◽  
Inertial Sensor ◽  
Stair Climbing ◽  
Measurement Unit ◽  
Inertial Measurement ◽  
Fast Walking ◽  
Zero Velocity ◽  
Wide Range ◽  
Algorithm Implementation

Previous studies show that inertial sensor-based personal positioning benefited from Zero Velocity Update (ZUPT) method by resetting the foot speed at every foot step. However, only the solution for normal pedestrian movement with small velocity like walking was given. This paper presents a novel ZUPT system which can be used in a wide range of human activities, including walking, running, and stair climbing by using two inertial measurement unit (IMU) modules. One is attached on the centre of the human body for human activities’ classification and recognition. The other one is mounted on the foot for ZUPT algorithm implementation based on the result of activities’ recognition. Test cases include stair climbing by walking and running, walking, fast walking, and running. In all cases, most of the steps are able to be detected and the new ZUPT system can be successfully implemented.

Thermogravimetric studies on co-pyrolysis of raw/torrefied biomass and coal blends

2020 ◽  
Vol 38 (11) ◽  
pp. 1259-1268
Author(s):  
NL Panwar ◽  
Bhautik Gajera ◽  
Sudhir Jain ◽  
BL Salvi
Keyword(s):  
Thermogravimetric Analysis ◽  
Thermal Degradation ◽  
Physicochemical Properties ◽  
Model Fitting ◽  
Cotton Stalk ◽  
Fitting Method ◽  
Torrefied Biomass ◽  
Three Stages ◽  
Thermogravimetric Studies ◽  
Kinetics Of

The pyrolysis and co-pyrolysis behaviours of cotton stalk (CS), torrefied cotton stalk (TCS) and mined coal, as single fuels, and their blends, have been examined through thermogravimetric analysis. Biomass has been torrefied at 250°C for 45 min to enhance physicochemical properties, and then mixed with mined coal for co-pyrolysis. Thermal degradation of CS and TCS is characterized by a reaction. However, this is not the case for mined coal, which shows a single-stage reaction. The thermal degradation of all blends was done in three stages: dehydration; biomass and small mined coal; and lignin or mined coal. A similar trend emerged for mass loss of individual fuels, which depended mainly on their ratios in the blend. The kinetics of pyrolysis and co-pyrolysis of all fuels were calculated at 20°Cmin−1 heating rate using the Coats−Redfern model-fitting method.

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