scholarly journals Monitoring of Sitting Postures With Sensor Networks in Controlled and Free-living Environments: Systematic Review

10.2196/21105 ◽  
2021 ◽  
Vol 6 (1) ◽  
pp. e21105
Author(s):  
Arpita Mallikarjuna Kappattanavar ◽  
Nico Steckhan ◽  
Jan Philipp Sachs ◽  
Harry Freitas da Cruz ◽  
Erwin Böttinger ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Pressure Sensors ◽  
Ground Truth ◽  
Living Environment ◽  
Measurement Unit ◽  
Future Research ◽  
Free Living ◽  
Medium Quality ◽  
Underlying Causes ◽  
Future Work

Background A majority of employees in the industrial world spend most of their working time in a seated position. Monitoring sitting postures can provide insights into the underlying causes of occupational discomforts such as low back pain. Objective This study focuses on the technologies and algorithms used to classify sitting postures on a chair with respect to spine and limb movements. Methods A total of three electronic literature databases were surveyed to identify studies classifying sitting postures in adults. Quality appraisal was performed to extract critical details and assess biases in the shortlisted papers. Results A total of 14 papers were shortlisted from 952 papers obtained after a systematic search. The majority of the studies used pressure sensors to measure sitting postures, whereas neural networks were the most frequently used approaches for classification tasks in this context. Only 2 studies were performed in a free-living environment. Most studies presented ethical and methodological shortcomings. Moreover, the findings indicate that the strategic placement of sensors can lead to better performance and lower costs. Conclusions The included studies differed in various aspects of design and analysis. The majority of studies were rated as medium quality according to our assessment. Our study suggests that future work for posture classification can benefit from using inertial measurement unit sensors, since they make it possible to differentiate among spine movements and similar postures, considering transitional movements between postures, and using three-dimensional cameras to annotate the data for ground truth. Finally, comparing such studies is challenging, as there are no standard definitions of sitting postures that could be used for classification. In addition, this study identifies five basic sitting postures along with different combinations of limb and spine movements to help guide future research efforts.

scholarly journals Monitoring of sitting postures with sensor networks in controlled and free-living environments: A systematic review (Preprint)

2020 ◽  
Author(s):  
Arpita Kappattanavar ◽  
Nico Steckhan ◽  
Jan Philipp Sachs ◽  
Bert Arnrich ◽  
Erwin Böttinger
Keyword(s):  
Pressure Sensors ◽  
Classification Problem ◽  
Living Environment ◽  
Free Living ◽  
Data Set ◽  
Posture Analysis ◽  
Sitting Posture ◽  
Prolonged Sitting ◽  
Medium Quality

BACKGROUND Background: Prolonged sitting postures have been reported to increase the probability of developing low back pain. Moreover, the majority of employees in the industrial world work ninety percent of their time in a seated position. OBJECTIVE This review focuses on the technologies and algorithms that have been used to classify seating postures on a chair with respect to spine and limb movements. METHODS Three electronic literature databases have been surveyed to identify the studies classifying sitting posture in adults. Fourteen articles have been finally shortlisted. These articles were categorized into low, medium, and high quality. Most of the articles were categorized as medium quality (12/14). RESULTS The majority of the studies used pressure sensors (13/14) to classify sitting postures. Neural Networks were the most frequently (6/14) used approaches for classifying sitting postures. CONCLUSIONS Based on the current study the classification of sitting posture is still in the nascent stage and hence, we would suggest personalized sitting posture analysis. Furthermore, the review emphasizes identifying at least five basic postures along with different limb and spine movements in a free-living environment. It is essential to annotate the data set with ground truths for subsequent training of the classifier to solve the sitting posture classification problem.

scholarly journals Investigation into Hand Scraping: A Microanalysis

2018 ◽  
Vol 2 (4) ◽  
pp. 76 ◽  
Author(s):  
Kai Oßwald ◽  
Ingo Lochmahr ◽  
Yasin Bagci ◽  
Peter Saile
Keyword(s):  
Inertial Measurement Unit ◽  
Three Dimensional ◽  
Movement Pattern ◽  
Measurement Unit ◽  
Surface Finishing ◽  
Future Research ◽  
Tool Orientation ◽  
Inertial Measurement ◽  
Finishing Process ◽  
Basic Characteristics

Hand scraping is a manual surface finishing process that, despite its low productivity and high cost, is still applied in many industries because of its advantages concerning accuracy and tribology. In the presented microanalysis forces, movement patterns and tool orientation of individual hand scraping strokes were measured using a test stand, specifically designed for this purpose. It utilizes a camera, a three dimensional dynamometer, and an inertial measurement unit (IMU). The results show the basic characteristics of hand scraping. Typical courses of relevant quantities like cutting force, passive force, clearance, and directional angle are shown. In addition, the movement pattern of the tool during individual scraping strokes is analyzed. This research aims to contribute to a later implementation of automated scraping. The conducted research creates a base for future research regarding different scraping methods and achieved results.

scholarly journals The Zurich urban micro aerial vehicle dataset

2017 ◽  
Vol 36 (3) ◽  
pp. 269-273 ◽  
Author(s):  
András L Majdik ◽  
Charles Till ◽  
Davide Scaramuzza
Keyword(s):  
Three Dimensional ◽  
Ground Truth ◽  
Ground Level ◽  
Urban Environments ◽  
Sensor Data ◽  
Measurement Unit ◽  
Reconstruction Algorithms ◽  
Ground Truth Data ◽  
Micro Aerial Vehicle ◽  
Aerial Vehicle

This paper presents a dataset recorded on-board a camera-equipped micro aerial vehicle flying within the urban streets of Zurich, Switzerland, at low altitudes (i.e. 5–15 m above the ground). The 2 km dataset consists of time synchronized aerial high-resolution images, global position system and inertial measurement unit sensor data, ground-level street view images, and ground truth data. The dataset is ideal to evaluate and benchmark appearance-based localization, monocular visual odometry, simultaneous localization and mapping, and online three-dimensional reconstruction algorithms for micro aerial vehicles in urban environments.

scholarly journals Application and Reliability of Arm Use Intensities in the Free-Living Environment for Manual Wheelchair Users

2020 ◽  
Author(s):  
Brianna M Goodwin ◽  
Omid Jahanian ◽  
Meegan G Van Straaten ◽  
Emma Fortune ◽  
Stefan I Madansingh ◽  
...  
Keyword(s):  
Data Collection ◽  
Living Environment ◽  
Video Data ◽  
Future Research ◽  
Intensity Level ◽  
Free Living ◽  
Wheelchair Users ◽  
Cord Injury ◽  
Measurement Units ◽  
Reliable Representation

Arm use in individuals with spinal cord injury who use manual wheelchairs (MWC) is complex, characterized by a combination of overuse and a sedentary lifestyle. This study aimed to calculate arm use intensity levels for MWC users, describe the percentage of daily wear time MWC users and able-bodied individuals spend in each arm use intensity level, and test the reliabilities of the measurements for both MWC users and ablebodied individuals. MWC users wore two inertial measurement units (IMUs) on their bilateral upper arms while performing six MWC-based activities in-lab. Video data were recorded and each second was coded as active or stationary. Acceleration-based signal magnitude area (SMA) ranges were defined for stationary, low, mid, and high arm use intensity levels. IMU data were also collected in the freeliving environments for MWC users and able-bodied individuals for four days (3 weekdays and 1 weekend day). The SMA levels were applied to the free-living data from the dominant arm and the percentage of time spent in each level was calculated. The required number of days to achieve moderate, good, and excellent reliabilities was calculated. Eight adult MWC users with SCI participated in the in-lab data collection and SMA arm use intensity levels were defined as, stationary: ≤ 0.67g, low: 0.671-3.27g, mid: 3.271-5.87, and high: > 5.871. Six MWC users and 15 able-bodied individuals completed the free-living data collection. The dominant arm of both MWC users and able-bodied individuals was stationary for the majority of the day. The reliability analysis indicated that at least five and eight days of data are needed from MWC users and ablebodied individuals, respectively, to achieve reliable representation of their overall daily arm use intensities throughout a week. Future research is needed to understand the recovery time associated with stationary arm use and if it differs between MWC users and matched able-bodied individuals. At least five days of data should be collected when utilizing these methods for MWC users. The methods presented here will contribute to understanding the mechanisms which cause increased shoulder pain and pathology for MWC users.

scholarly journals Actigraphy-Based Associations Between Chronotype and Physical Activity in Older Adults

2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. 784-784
Author(s):  
Hilary Hicks ◽  
Genna Losinski ◽  
Alexandra Laffer ◽  
Amber Watts
Keyword(s):  
Physical Activity ◽  
Older Adults ◽  
Older Adult ◽  
Total Activity ◽  
Time Of Day ◽  
Living Environment ◽  
Future Research ◽  
Free Living ◽  
Middle Aged Adults ◽  
The Relationship

Abstract Chronotype is a measure of the time of day people prefer to be most active or to sleep. There is a known relationship between chronotype and engagement in physical activity in young and middle-aged adults, such that individuals with a morning chronotype engage in more physical activity compared to those with an evening chronotype. Our study aimed to replicate this finding in an older adult sample. Actigraphy can be used to measure both physical activity and sleep. Because of its ability to capture information about bedtime and arise time, actigraphy can serve as an objective measurement of chronotype. Participants were 159 older adults (ages 60-89, M = 74.73) who wore an ActiGraph GT9X on their non-dominant wrist for 7 days in a free-living environment. Chronotype was measured continuously using the midpoint of the ActiGraph-calculated sleep interval. We used multiple regression to determine the relationship between physical activity and chronotype adjusting for sex, age, and body mass index. Results suggest that while these variables explain a significant amount of variance in physical activity, R2 = 19.0%, F (4, 152) = 8.921, p < .001, there is no significant relationship between chronotype and total physical activity in our sample, ß= -.117, p = .114. These findings are inconsistent with what has been shown in younger samples and suggest that the relationship between chronotype and physical activity may change as one ages. Future research should consider whether particular physical activity intensities (vs. total activity) may have a relationship with chronotype in older adults.

The UMA-SAR Dataset: Multimodal data collection from a ground vehicle during outdoor disaster response training exercises

2021 ◽  
pp. 027836492110049
Author(s):  
Jesús Morales ◽  
Ricardo Vázquez-Martín ◽  
Anthony Mandow ◽  
David Morilla-Cabello ◽  
Alfonso García-Cerezo
Keyword(s):  
Disaster Response ◽  
Three Dimensional ◽  
Ground Truth ◽  
Measurement Unit ◽  
Emergency Responders ◽  
Full Dataset ◽  
Total Path Length ◽  
Localization And Mapping ◽  
Wide Range ◽  
Detection And Localization

This article presents a collection of multimodal raw data captured from a manned all-terrain vehicle in the course of two realistic outdoor search and rescue (SAR) exercises for actual emergency responders conducted in Málaga (Spain) in 2018 and 2019: the UMA-SAR dataset. The sensor suite, applicable to unmanned ground vehicles (UGVs), consisted of overlapping visible light (RGB) and thermal infrared (TIR) forward-looking monocular cameras, a Velodyne HDL-32 three-dimensional (3D) lidar, as well as an inertial measurement unit (IMU) and two global positioning system (GPS) receivers as ground truth. Our mission was to collect a wide range of data from the SAR domain, including persons, vehicles, debris, and SAR activity on unstructured terrain. In particular, four data sequences were collected following closed-loop routes during the exercises, with a total path length of 5.2 km and a total time of 77 min. In addition, we provide three more sequences of the empty site for comparison purposes (an extra 4.9 km and 46 min). Furthermore, the data is offered both in human-readable format and as rosbag files, and two specific software tools are provided for extracting and adapting this dataset to the users’ preference. The review of previously published disaster robotics repositories indicates that this dataset can contribute to fill a gap regarding visual and thermal datasets and can serve as a research tool for cross-cutting areas such as multispectral image fusion, machine learning for scene understanding, person and object detection, and localization and mapping in unstructured environments. The full dataset is publicly available at: www.uma.es/robotics-and-mechatronics/sar-datasets .

scholarly journals Estimating Walking Speed in the Wild

2020 ◽  
Vol 2 ◽  
Author(s):  
Loubna Baroudi ◽  
Mark W. Newman ◽  
Elizabeth A. Jackson ◽  
Kira Barton ◽  
K. Alex Shorter ◽  
...  
Keyword(s):  
Physical Activity ◽  
Clinical Decision Making ◽  
Walking Speed ◽  
Wearable Sensors ◽  
Clinical Decision ◽  
Living Environment ◽  
Activity Level ◽  
Measurement Unit ◽  
Battery Life ◽  
Free Living

An individual's physical activity substantially impacts the potential for prevention and recovery from diverse health issues, including cardiovascular diseases. Precise quantification of a patient's level of day-to-day physical activity, which can be characterized by the type, intensity, and duration of movement, is crucial for clinicians. Walking is a primary and fundamental physical activity for most individuals. Walking speed has been shown to correlate with various heart pathologies and overall function. As such, it is often used as a metric to assess health performance. A range of clinical walking tests exist to evaluate gait and inform clinical decision-making. However, these assessments are often short, provide qualitative movement assessments, and are performed in a clinical setting that is not representative of the real-world. Technological advancements in wearable sensing and associated algorithms enable new opportunities to complement in-clinic evaluations of movement during free-living. However, the use of wearable devices to inform clinical decisions presents several challenges, including lack of subject compliance and limited sensor battery life. To bridge the gap between free-living and clinical environments, we propose an approach in which we utilize different wearable sensors at different temporal scales and resolutions. Here, we present a method to accurately estimate gait speed in the free-living environment from a low-power, lightweight accelerometer-based bio-logging tag secured on the thigh. We use high-resolution measurements of gait kinematics to build subject-specific data-driven models to accurately map stride frequencies extracted from the bio-logging system to stride speeds. The model-based estimates of stride speed were evaluated using a long outdoor walk and compared to stride parameters calculated from a foot-worn inertial measurement unit using the zero-velocity update algorithm. The proposed method presents an average concordance correlation coefficient of 0.80 for all subjects, and 97% of the error is within ±0.2m· s−1. The approach presented here provides promising results that can enable clinicians to complement their existing assessments of activity level and fitness with measurements of movement duration and intensity (walking speed) extracted at a week time scale and in the patients' free-living environment.

Development and Construct Validation of the German Workplace Trust Survey (G-WTS)

2010 ◽  
Vol 26 (1) ◽  
pp. 3-10 ◽  
Author(s):  
Nale Lehmann-Willenbrock ◽  
Simone Kauffeld
Keyword(s):  
Convergent Validity ◽  
Affective Commitment ◽  
Discriminant Validity ◽  
Organizational Context ◽  
Organizational Trust ◽  
Three Dimensional ◽  
Future Research ◽  
Work Related ◽  
Reliable Assessment ◽  
Workplace Trust

In research on trust in the organizational context, there is some agreement evolving that trust should be measured with respect to various foci. The Workplace Trust Survey (WTS) by Ferres (2002) provides reliable assessment of coworker, supervisor, and organizational trust. By means of a functionally equivalent translation, we developed a German version of the questionnaire (G-WTS) comprising 21 items. A total of 427 employees were surveyed with the G-WTS and questionnaires concerning several work-related attitudes and behaviors and 92 of these completed the survey twice. The hypothesized three-dimensional conceptualization of organizational trust was confirmed by confirmatory factor analysis. The G-WTS showed good internal consistency and retest reliability values. Concerning convergent validity, all of the three G-WTS dimensions positively predicted job satisfaction. In terms of discriminant validity, Coworker Trust enhanced group cohesion; Supervisor Trust fostered innovative behavior, while Organizational Trust was associated with affective commitment. Theoretical and practical contributions as well as opportunities for future research with the G-WTS are discussed.

scholarly journals Three-Dimensional Thematic Map Imaging of the Yacht Port on the Example of the Polish National Sailing Centre Marina in Gdańsk

2021 ◽  
Vol 11 (15) ◽  
pp. 7016
Author(s):  
Pawel S. Dabrowski ◽  
Cezary Specht ◽  
Mariusz Specht ◽  
Artur Makar
Keyword(s):  
Spatial Data ◽  
Convex Surface ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Future Research ◽  
Two Dimensional ◽  
Thematic Maps ◽  
Research Directions ◽  
Future Research Directions ◽  
The Many

The theory of cartographic projections is a tool which can present the convex surface of the Earth on the plane. Of the many types of maps, thematic maps perform an important function due to the wide possibilities of adapting their content to current needs. The limitation of classic maps is their two-dimensional nature. In the era of rapidly growing methods of mass acquisition of spatial data, the use of flat images is often not enough to reveal the level of complexity of certain objects. In this case, it is necessary to use visualization in three-dimensional space. The motivation to conduct the study was the use of cartographic projections methods, spatial transformations, and the possibilities offered by thematic maps to create thematic three-dimensional map imaging (T3DMI). The authors presented a practical verification of the adopted methodology to create a T3DMI visualization of the marina of the National Sailing Centre of the Gdańsk University of Physical Education and Sport (Poland). The profiled characteristics of the object were used to emphasize the key elements of its function. The results confirmed the increase in the interpretative capabilities of the T3DMI method, relative to classic two-dimensional maps. Additionally, the study suggested future research directions of the presented solution.

scholarly journals An Exit Strategy for the Definitional Elusiveness: A Three-Dimensional Framework for Social Entrepreneurship

2021 ◽  
Vol 13 (2) ◽  
pp. 563
Author(s):  
Bing Ran ◽  
Scott Weller
Keyword(s):  
Social Change ◽  
Literature Review ◽  
Systematic Literature Review ◽  
Social Entrepreneurship ◽  
Common Ground ◽  
Three Dimensional ◽  
Theoretical Framework ◽  
Future Research ◽  
Exit Strategy ◽  
Conceptual Paper

Despite the growing utility and prevalence of social entrepreneurship, an accepted definition remains elusive and infeasible. Yet, it is imperative that the principles guiding social entrepreneurship are identified so that common ground is established to facilitate future research. On the basis of a systematic literature review, this conceptual paper proposes a theoretical framework outlining social entrepreneurship as a three-dimensional framework as a function of continua of “social” and “business” logics, “beneficial” and “detrimental” social change logics, and “innovation” and “mundane” logics. The framework accommodates the fuzziness and ambiguity associated with social entrepreneurship whilst remaining a workable, identifiable construct. By accounting for the shifting logics practiced by social entrepreneurship that both influence and are influenced by the organizational environment, this framework provides an exit strategy for the definitional elusiveness of social entrepreneurship. The resultant structures and functions of social entrepreneurship are shaped by these constraints as reflected by the fluidity and flexibility endorsed by the framework. Four avenues for future research regarding social entrepreneurship are recommended on the basis of the framework proposed in this article.

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