scholarly journals A Novel Macro-Micro Approach for Swimming Analysis in Main Swimming Techniques Using IMU Sensors

Author(s):  
Mahdi Hamidi Rad ◽  
Vincent Gremeaux ◽  
Farzin Dadashi ◽  
Kamiar Aminian

Inertial measurement units (IMU) are proven as efficient tools for swimming analysis by overcoming the limits of video-based systems application in aquatic environments. However, coaches still believe in the lack of a reliable and easy-to-use analysis system for swimming. To provide a broad view of swimmers' performance, this paper describes a new macro-micro analysis approach, comprehensive enough to cover a full training session, regardless of the swimming technique. Seventeen national level swimmers (5 females, 12 males, 19.6 ± 2.1 yrs) were equipped with six IMUs and asked to swim 4 × 50 m trials in each swimming technique (i.e., frontcrawl, breaststroke, butterfly, and backstroke) in a 25 m pool, in front of five 2-D cameras (four under water and one over water) for validation. The proposed approach detects swimming bouts, laps, and swimming technique in macro level and swimming phases in micro level on all sensor locations for comparison. Swimming phases are the phases swimmers pass from wall to wall (wall push-off, glide, strokes preparation, swimming, and turn) and micro analysis detects the beginning of each phase. For macro analysis, an overall accuracy range of 0.83–0.98, 0.80–1.00, and 0.83–0.99 were achieved, respectively, for swimming bouts detection, laps detection and swimming technique identification on selected sensor locations, the highest being achieved with sacrum. For micro analysis, we obtained the lowest error mean and standard deviation on sacrum for the beginning of wall-push off, glide and turn (−20 ± 89 ms, 4 ± 100 ms, 23 ± 97 ms, respectively), on shank for the beginning of strokes preparation (0 ± 88 ms) and on wrist for the beginning of swimming (−42 ± 72 ms). Comparing the swimming techniques, sacrum sensor achieves the smallest range of error mean and standard deviation during micro analysis. By using the same macro-micro approach across different swimming techniques, this study shows its efficiency to detect the main events and phases of a training session. Moreover, comparing the results of both macro and micro analyses, sacrum has achieved relatively higher amounts of accuracy and lower mean and standard deviation of error in all swimming techniques.

Author(s):  
Stephanie L. Carey ◽  
Kevin Hufford ◽  
Amanda Martori ◽  
Mario Simoes ◽  
Francy Sinatra ◽  
...  

Mild traumatic brain injuries (mTBI) stem from a number of causes such as illnesses, strokes, accidents or battlefield traumas. These injuries can cause issues with everyday tasks, such as gait, and are linked with vestibular dysfunction [1]. Current technology that measures gait parameters often requires time consuming set up and post processing and is limited to the laboratory setting. The purpose of this study was to develop a wearable motion analysis system (WMAS) using five commercially available inertial measurement units (IMU) working in unison to record and output four gait parameters in a clinically relevant way. The WMAS has the potential to be used to 1) help diagnose mTBI or other neurocognitive disorders; 2) provide feedback to a clinician during a training session; 3) collect gait parameter data outside of the laboratory setting to determine rehabilitation progress; 4) provide quantitative outcome measures for rehabilitation efficacy.


2018 ◽  
Vol 9 (5) ◽  
pp. 388-407
Author(s):  
Patricio Gigli ◽  
◽  
Donatela Orsi ◽  
Marisel Martín Aramburú ◽  
◽  
...  

This paper aims at describing the experience of the Cities for Entrepreneurs Program (Ciudades para Emprender or CPE) of the National Directorate of Community and Human Capital (which belongs to the SEPYME), National Ministry of Production. This paper starts from the premise that entrepreneurship takes place at the most micro level of the offer and, therefore, is a concept associated with the characteristics of the environment closest to that offer: the local territory. However, there is little history in the country of public policies relating the issue of entrepreneurship with the local management. That is why we take as a starting point the conceptualization of the chosen framework: local governments and the development issue, seen from the perspective of entrepreneurships. Moreover, an overview is given on the structural characteristics of municipalities in Argentina. In addition, some international experiences and attempts to promote entrepreneurship at a national level are analyzed. Finally, the Cities for Entrepreneurs Program (CPE) is outlined, based on a summary of the diagnoses of the Entrepreneurial Ecosystems of the selected cities and the tools used and their execution status at the time of publication of this paper.


2021 ◽  
Vol 14 (3) ◽  
pp. 283
Author(s):  
Félix Lobo ◽  
Isabel Río-Álvarez

Incentives contribute to the proper functioning of the broader contracts that regulate the relationships between health systems and professionals. Likewise, incentives are an important element of clinical governance understood as health services’ management at the micro-level, aimed at achieving better health outcomes for patients. In Spain, monetary and non-monetary incentives are sometimes used in the health services, but not as frequently as in other countries. There are already several examples in European countries of initiatives searching the promotion of biosimilars through different sorts of incentives, but not in Spain. Hence, this paper is aimed at identifying the barriers that incentives to prescribe biosimilars might encounter in Spain, with particular interest in incentives in the framework of clinical governance. Both questions are intertwined. Barriers are presented from two perspectives. Firstly, based on the nature of the barrier: (i) the payment system for health professionals, (ii) budget rigidity and excessive bureaucracy, (iii) little autonomy in the management of human resources (iv) lack of clinical integration, (v) absence of a legal framework for clinical governance, and (vi) other governance-related barriers. The second perspective is based on the stakeholders involved: (i) gaps in knowledge among physicians, (ii) misinformation and distrust among patients, (iii) trade unions opposition to productivity-related payments, (iv) lack of a clear position by professional associations, and (v) misalignment of the goals pursued by some healthcare professionals and the goals of the public system. Finally, the authors advance several recommendations to overcome these barriers at the national level.


2004 ◽  
Vol 124 (4) ◽  
pp. 148-149 ◽  
Author(s):  
Osamu Kawatoko ◽  
Rei Yoneyama ◽  
Hiroaki Suzuki

2021 ◽  
Vol 5 (1) ◽  
pp. 62-72
Author(s):  
Yuhai Peng

Cognitive metaphor is an important way and mechanism of semantic derivation of verbs, the resulting large number of verbal metaphorical sememes has different expressions in their semantic features, formal syntax, communicative structure and even modality and pragmatics. This paper thoroughly and carefully discusses the problem of semantic change of verbal metaphor in terms of the integrated description method of the Moscow Semantic School. Thus, we will create a unique and innovative framework and theoretical model of generalized formal feature analysis, we will also try to introduce formal semantic description and micro-level semantic interpretation into the analysis system of semantic change of the verbal metaphor. Furthermore, we will describe in detail and characterize a number of changes caused by metaphorical semantic change of Russian verbs from the perspective of multi-dimensional integration. This study breaks down the barriers between semantics, cognition, pragmatics and grammar and the traditional analysis pattern of semantic derivation which contributes to significant broadening of the theoretical semantic vision and deepening of the research of cognitive semantics problems of verbal metaphor. It also helps explore innovative analytical methods and strategies for the study of Russian lexical and syntactic semantics.


2017 ◽  
Vol 50 (1) ◽  
pp. 217-239 ◽  
Author(s):  
Amanda Lea Robinson

AbstractEthnic diversity is generally associated with less social capital and lower levels of trust. However, most empirical evidence for this relationship is focused on generalized trust, rather than more theoretically appropriate measures of group-based trust. This article evaluates the relationship between ethnic diversity – at the national, regional and local levels – and the degree to which coethnics are trusted more than non-coethnics, a value referred to here as the ‘coethnic trust premium’. Using public opinion data from sixteen African countries, this study finds that citizens of ethnically diverse states express, on average, more ethnocentric trust. However, within countries, regional ethnic diversity is associated with less ethnocentric trust. This same negative pattern between diversity and ethnocentric trust appears across districts and enumeration areas within Malawi. The article then shows, consistent with these patterns, that diversity is only detrimental to intergroup trust at the national level when ethnic groups are spatially segregated. These results highlight the importance of the spatial distribution of ethnic groups on intergroup relations, and question the utility of micro-level studies of interethnic interactions for understanding macro-level group dynamics.


2018 ◽  
Vol 10 (11) ◽  
pp. 1803 ◽  
Author(s):  
Qu Zhou ◽  
Liqiao Tian ◽  
Jian Li ◽  
Qingjun Song ◽  
Wenkai Li

The Moderate-Resolution Wide-Wavelength Imager (MWI), onboard the Tiangong-2 (TG-2) Space Lab, is an experimental satellite sensor designed for the next-generation Chinese ocean color satellites. The MWI imagery is not sufficiently radiometrically calibrated, and therefore, the cross-calibration is urgently needed to provide high quality ocean color products for MWI observations. We proposed a simple and effective cross-calibration scheme for MWI data using well calibrated Moderate Resolution Imaging Spectroradiometer (MODIS) imagery over aquatic environments. The path radiance of the MWI was estimated using the quasi-synchronized MODIS images as well as the MODIS Rayleigh and aerosol look up tables (LUTs) from SeaWiFS Data Analysis System 7.4 (SeaDAS 7.4). The results showed that the coefficients of determination (R2) of the calibration coefficients were larger than 0.97, with sufficient matched areas to perform cross-calibration for MWI. Compared with the simulated Top of Atmosphere (TOA) radiance using synchronized MODIS images, all errors calculated with the calibration coefficients retrieved in this paper were less than 5.2%, and lower than the lab calibrated coefficients. The Rayleigh-corrected reflectance (ρrc), remote sensing reflectance (Rrs) and total suspended matter (TSM) products of MWI, MODIS and the Geostationary Ocean Color Imager (GOCI) images for Taihu Lake in China were compared. The distribution of ρrc of MWI, MODIS and GOCI agreed well, except for band 667 nm of MODIS, which might have been saturated in relatively turbid waters. Besides, the Rrs used to retrieve TSM among MWI, MODIS and GOCI was also consistent. The root mean square errors (RMSE), mean biases (MB) and mean ratios (MR) between MWI Rrs and MODIS Rrs (or GOCI Rrs) were less than 0.20 sr−1, 5.52% and within 1 ± 0.023, respectively. In addition, the derived TSM from MWI and GOCI also agreed with a R2 of 0.90, MB of 13.75%, MR of 0.97 and RMSE of 9.43 mg/L. Cross-calibration coefficients retrieved in this paper will contribute to quantitative applications of MWI. This method can be extended easily to other similar ocean color satellite missions.


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