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Dose-response associations,physical activity intensity and mortality risk:A narrative review

Journal of Sport and Health Science 2024年第1期13卷 24-29页

作者： Ulf Ekelund Miguel Adriano Sanchez-Lastra Knut Eirik Dalene Jakob Tarp Department of Sport Medicine Norwegian School of Sport SciencesOslo 0806Norway Department of Chronic Diseases Norwegian Institute of Public HealthOslo 0213Norway Department of Special Didactics Faculty of Education and Sports SciencesUniversity of VigoPontevedra 36005Spain Well-Move Research Group Galicia-Sur Health Research Institute(SERGAS-UVIGO)Vigo 36213Spain

Physical activity is consistently associated with reduced mortality,decreased risk for non-communicable diseases,and improved mental health in observational studies.Randomized controlled trials and observational Mendelian randomization studies support causal links between physical activity and health outcomes.However,the scarcity of evidence from randomized controlled trials,along with their inherent challenges like exposure contrasts,healthy volunteer biases,loss to follow-up,and limited real-world dose-response data,warrants a comprehensive approach.This review advocates synthesizing insights from diverse study designs to better understand the causal relationship between physical activity,mortality risk,and other health outcomes.Additionally,it summarizes recent research since the publication of current physical activity recommendations.Novel observational studies utilizing device-measured physical activity underscore the importance of every minute of activity and suggest that all intensity levels confer health benefits,with vigorous-intensity potentially requiring lower volumes for substantial benefits.Future guidelines,informed by device-measured physical activity studies,may offer refined age-specific recommendations,emphasize vigorous-intensity physical activity,and include daily step counts as a simple,easily assessable metric using commercial wearables.

关键词： accelerometers Non-communicable diseases Public health Sedentary behavior

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Eigenfrequency analysis of bridges using a smartphone and a novel low-cost accelerometer prototype

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Frontiers of Structural and Civil Engineering 2024年第2期18卷 202-215页

作者： Seyedmilad KOMARIZADEHASL Ye XIA Mahyad KOMARY Fidel LOZANO Department of Civil and Environment Engineering Universitat Politècnica de CatalunyaBarcelona 08034Spain Department of Bridge Engineering Tongji UniversityShanghai 200092China Department of Civil Engineering Universidad de Castilla-La ManchaCiudad Real 13071Spain

Researchers are paying increasing attention to the development of low-cost and microcontroller-based accelerometers,in order to make structural health monitoring feasible for conventional bridges with limited monitoring budget.Parallel with the low-cost sensor development,the use of the embedded accelerometers of smartphones for eigenfrequency analysis of bridges is becoming popular in the civil engineering literature.This paper,for the first time in the literature,studies these two promising technologies by comparing the noise density and eigenfrequency analysis of a self-developed,validated and calibrated low-cost Internet of things based accelerometer LARA(low cost adaptable reliable accelerometer)with those of a state of the art smartphone(iPhone XR).The eigenfrequency analysis of a footbridge in San Sebastian,Spain,showed that the embedded accelerometer of the iPhone XR can measure the natural frequencies of the under study bridge.

关键词： smartphone modal analysis eigenfrequency analysis low-cost accelerometers Arduino Raspberry Internet of things

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New self-calibration schemes for accelerometers in platform INS

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Journal of Systems Engineering and Electronics 2015年第5期26卷 1032-1042页

作者： Hong Cai Anliang Li Yuan Cao College of Aerospace Science and Engineering National University of Defence Technology Science and Technology on Complex Land Systems Simulation Laboratory

To ensure success of precise navigation, it is necessary to carry out in-field calibration for the accelerometers in platform inertial navigation system(PINS) before a mission is launched.Traditional continuous self-calibration methods are not fit for fast calibration of accelerometers because the platform misalignments have to be estimated precisely and the nonlinear coupling terms will affect accuracy. The multi-position methods with a "shape of motion" algorithm also have some existing disadvantages: High precision calibration results cannot be obtained when the accelerometer’s output data are used directly and it is difficult to optimize the calibration scheme. Focusing on this field, this paper proposes new fast self-calibration methods for the accelerometers of PINS. A data compression filter is employed to improve the accuracy of parameter estimation because it is impossible to obtain non-biased estimation for accelerometer parameters when using the "shape of motion" algorithm. Besides, continuous calibration schemes are designed and optimized by the genetic algorithm(GA) to improve the observability of parameters. Simulations prove that the proposed methods can estimate the accelerometer parameter more precisely than traditional continuous methods and multi-position methods, and they are more practical to deal with urgent situations than multi-position methods.

关键词： self-calibration accelerometers data compression genetic algorithm

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Wearable monitors criterion validity for energy expenditure in sedentary and light activities

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Journal of Sport and Health Science 2017年第1期6卷 103-110页

作者： Florez-Pregonero Alberto Meckes Nathanael Buman Mathew Barbara E.Ainsworth Departamento de Formación Facultad de EducaciónPontificia Universidad JaverianaBogotaDistrito Capital 11001000Colombia Department of Exercise and Sport Science School of Behavioral and Applied SciencesAzuza Pacific UniversityAzuzaCA 91702USA School of Nutrition and Health Promotion Arizona State UniversityPhoenixAZ 85004USA

Background: Wearable monitors(WMs) are used to estimate the time spent in sedentary behaviors(SBs) and light-intensity physical activities(LPAs) and their associated energy cost; however, the accuracy of WMs in measuring behaviors on the lower end of the intensity spectrum is unclear. The aim of this study was to assess the validity of 3 WMs(Acti Graph GT3X+; activ PAL, and Sense Wear 2) in estimating the intensity of SB and LPA in adults as compared with the criterion measure of oxygen uptake(VO_2) measured by indirect calorimetry.Methods: Sixteen participants(age: 25.38 ± 8.58 years) wore the ActiG raph GT3X+, activP AL, and SenseW ear 2 devices during 7 sedentary-to-light activities. VO_2(mL/kg/min) was estimated by means of a portable gas analyzer, Oxycon Mobile(Carefusion, Yorba Linda, CA, USA). All data were transformed into metabolic equivalents and analyzed using mean percentage error, equivalence plots, Bland-Altman plots, kappa statistics, and sensitivity/specificity.Results: Mean percentage error was lowest for the activ PAL for SB(14.9%) and LPA(9.3%) compared with other WMs, which were >21.2%.None of the WMs fell within the equivalency range of ±10% of the criterion mean value. Bland-Altman plots revealed narrower levels of agreement with all WMs for SB than for LPA. Kappa statistics were low for all WMs, and sensitivity and specificity varied by WM type.Conclusion: None of the WMs tested in this study were equivalent with the criterion measure(VO_2) in estimating sedentary-to-light activities;however, the activ PAL had greater overall accuracy in measuring SB and LPA than did the Acti Graph and Sense Wear 2 monitors.

关键词： accelerometers Accuracy Low intensity Metabolic estimations Objective measurement Sedentary behaviors

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A methodology for the performance evaluation of low-cost accelerometer and magnetometer sensors in geomatics applications

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Geo-Spatial Information Science 2018年第2期21卷 139-148页

作者： Photis Patonis Petros Patias Ilias N.Tziavos Dimitrios Rossikopoulos Engineering School of Rural and Surveying Engineering Aristotle University of ThessalonikiThessalonikiGreece

This paper presents a methodology and its software implementation for the performance evaluation of low-cost accelerometer and magnetometer sensors for use in geomatics applications.A known mathematical calibration model has been adopted.The method was completed with statistical methodologies for adjusting observations and has been extended to calculate accuracies for the attitude,heading,and tilt angles estimation that are of interest to geomatics applications.The evaluation method consists of two stages.First,the evaluation method reviews the total magnitude of acceleration or the strength of the magnetic field.Second,the evaluation is more detailed and concerns the determination of mathematical parameters that describe both accelerometer and magnetometer working model.A software tool that implements the evaluation model has been developed and is applied both in accelerometer and magnetometer measurement data-sets acquired from a low-cost sensor system.

关键词： Low-cost sensors evaluation methodology accelerometers magnetometers attitude heading

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Inertial sensors technologies for navigation applications:state of the art and future trends

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Satellite Navigation 2020年第1期1卷 9-29页

作者： Naser El-Sheimy Ahmed Youssef Mobile Multi-sensor Systems Research Team Department of Geomatics EngineeringUniversity of Calgary2500 University Drive N.WCalgaryAB T2N 1N4Canada

Inertial navigation represents a unique method of navigation,in which there is no dependency on external sources of information.As opposed to other position fixing navigation techniques,inertial navigation performs the navigation in a relative sense with respect to the initial navigation state of the moving platform.Hence,inertial navigation systems are not prone to jamming,or spoofing.Inertial navigation systems have developed vastly,from their occurrence in the 1940s up to date.The accuracy of the inertial sensors has improved over time,making inertial sensors sufficient in terms of size,weight,cost,and accuracy for navigation and guidance applications.Within the past few years,inertial sensors have developed from being purely mechanical into incorporating various technologies and taking advantage of numerous physical phenomena,from which the dynamic forces exerted on a moving body could be computed accurately.Besides,the evolution of inertial navigation scheme involved the evolution from stable-platform inertial navigation system,which were mechanically complicated,to computationally demanding strap-down inertial navigation systems.Optical sensory technologies have provided highly accurate inertial sensors,at smaller sizes.Besides,the vibratory inertial navigation technologies enabled the production of Micro-electro-machined inertial sensors that are extremely low-cost,and offer extremely low size,weight and power consumption,making them suitable for a wide range of day-to-day navigation applications.Recently,advanced inertial sensor technologies have been introduced to the industry such as nuclear magnetic resonance technology,coldatom technology,and the reintroduction of fluid-based inertial sensors.On another note,inertial sensor errors constitute a huge research aspect in which it is intended for inertial sensors to reach level in which they could operate for substantially long operation times in the absence of updates from aiding sensors,which would be a huge leap.Inertial sensors error modeling technique

关键词： Gyroscopes accelerometers Optical inertial sensors Micro-electro-machined Fluid-based inertial sensors Stochastic modeling

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Compact FBG diaphragm accelerometer based on L-shaped rigid cantilever beam

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Chinese Optics Letters 2011年第10期9卷 18-21页

作者：翁银燕乔学光冯忠耀忽满利张敬花杨扬 Department of Physics Northwest University of China Key Laboratory of Photoelectricity Gas-Oil Logging and Detecting Ministry of EducationXi'an Shiyou University of China

A compact fiber Bragg grating （FBG） diaphragm accelerometer based on L-shaped rigid cantilever beam is proposed and experimentally demonstrated. The sensing system is based on the integration of a flat diaphragm and an L-shaped rigid cantilever beam. The FBG is pre-tensioned and the two side points are fixed, efficiently avoiding the unwanted chirp effect of grating. Dynamic vibration measurement shows that the proposed FBG diaphragm accelerometer provides a wide frequency response range （0-110 Hz） and an extremely high sensitivity （106.5 pm/g）, indentifying it as a good candidate for embedding structural health monitoring and seismic wave measurement.

关键词： accelerometers Cantilever beams Diaphragms Frequency response Nanocantilevers Sensors Structural health monitoring

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Performance of an Accelerometer Suspended by a Pendulum

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Chinese Physics Letters 2003年第8期20卷 1214-1216页

作者：高尚伟栾恩杰周泽兵罗俊 DepartmentofPhysics HuazhongUniversityofScienceandTechnologyWuhan430074

Performances of an accelerometer suspended by a pendulum and set on ground directly are both discussed. Theoretical analysis shows that the isolation from seismic disturbances of such a suspending accelerometer is equal to that of a narrow band-pass electronic filter. This means that the effect of seismic noises to the accelerometer can be substantially suppressed by means of a pendulum suspension during its performance tests.

关键词： accelerometers

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Flextensional fiber Bragg grating-based accelerometer for low frequency vibration measurement

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Chinese Optics Letters 2011年第9期9卷 25-28页

作者：张敬花乔学光忽满利冯忠耀高宏杨扬周锐 Department of Physics Northwest University of China

The intelligent structural health monitoring method, which uses a fiber Bragg grating （FBG） sensor, is a new approach in the field of civil engineering. However, it lacks a reliable FBG-based accelerometer for taking structural low frequency vibration measurements. In this letter, a fiextensional FBG-based accelerometer is proposed and demonstrated. The experimental results indicate that the natural frequency of the developed accelerometer is 16.7 Hz, with a high sensitivity of 410.7 pm/g. In addition, it has a broad and flat response over low frequencies ranging from 1 to 10 Hz. The natural frequency and sensitivity of the accelerometer can be tuned by adding mass to tailor the sensor performance to specific applications. Experimental results are presented to demonstrate the good performance of the proposed FBG-based accelerometer. These results show that the proposed accelerometer is satisfactory for low frequency vibration measurements.

关键词： accelerometers Civil engineering Frequency response Natural frequencies Sensors Structural health monitoring Vibration measurement

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A novel accelerometer based on microring resonator

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Chinese Optics Letters 2009年第9期7卷 798-801页

作者：莫文琴吴华明郜定山周治平 Wuhan National Laboratory for Optoelectronics College of Optoelectronie Science and Engineering Huazhong University of Science and Technology Faculty of Mechanical and Electronic Information China University of Geosciences Wuhan National Laboratory for Optoelectronics College of Optoelectronic Science and EngineeringHuazhong University of Science and Technology State Key Laboratory on Advanced Optical Communication Systems and Networks Peking University School of Electrical and Computer Engineering Georgia Institute of Technology

A novel microring resonator accelerometer is proposed. It is realized by a suspended straight waveguide coupled with a microring resonator. Under the external acceleration, the coupling coefficient is a function of gap spacing between the two waveguides. The mathematical model of the sensing element is established. Both the finite element method and coupled mode theory are adopted to analyze and optimize the proposed structure. Simulation results show that the mechanical sensitivity is 0.015 μm/g with the working frequency below 500 Hz and cross-axis sensitivity less than 0.001%, which is promising in seismic related applications.

关键词： accelerometers Mathematical models Waveguides

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