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3Report on testing of water overflow on Dutch levees. On the Dutch part of the levee in Hedwige-Prosperpolder, 11 overflow tests have been conducted. Overflow tests on levees are designed to test the strength of levees and levee covers under the load of a continuously overflowing discharge of water. For this purpose, Flanders Hydraulics Research have designed and built an Overflow Generator (Vercruysse et al., 2022) within the framework of the Polder2C’s project. This device allows to generate a controlled and homogenous discharge of water over the levee crest. Within the Polder2C’s project, 27 overflow tests on 11 Belgian and 11 Dutch levee stretches have been executed in 3 episodes from 30/10/20 to 28/11/20, 17/02/21 to 31/03/21 and 16/11/21 to 20/12/21. Different test goals have been addressed, to understand the normal performance of a levee cover, and the influence of different anomalies and/or deviations from the ‘standard’ levee.
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This report bundles the annexes for the data report of the overflow tests executed on the Dutch part of the Hedwige-Propserpolder levees. Overflow tests on levees are designed to test the strength of levees and levee covers under the load of a continuously overflowing discharge of water. For this purpose, Flanders Hydraulics Research have designed and built an Overflow Generator (Vercruysse et al., 2022) within the framework of the Polder2C’s project. This device allows to generate a controlled and homogenous discharge of water over the levee crest. Within the Polder2C’s project, 25 overflow tests on Belgian and Dutch levee stretches have been executed in 3 episodes from 30/10/20 to 28/11/20, 17/02/21 to 31/03/21 and 16/11/21 to 20/12/21. Different test goals have been addressed, to understand the normal performance of a levee cover, and the influence of different anomalies and/or deviations from the ‘standard’ levee.
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Report on testing of water overflow on Belgian levees. On the Belgian part of the levee at the Prosperpolder, 14 overflow tests have been conducted on 12 sections. Continuous overflow tests on levees are designed and executed to test the strength of levees and levee covers under the load of a continuously overflowing discharge of water. For this purpose, Flanders Hydraulics has designed and built an Overflow Generator (Vercruysse et al., 2022) within the framework of the Interreg Polder2C’s project. This device allows to generate a controlled and homogenous discharge of water flowing over the levee crest and slopes. Within the Polder2C’s project, 27 overflow tests on Belgian and Dutch levee stretches have been executed in 3 episodes from 30/10/20 to 28/11/20, 17/02/21 to 31/03/21 and 16/11/21 to 20/12/21. Different test goals have been addressed, to understand the normal performance of a levee cover, and the influence of different anomalies and/or deviations from the ‘standard’ levee.
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This report bundles the annexes for the data report of the overflow tests executed on the Belgian part of the Hedwige-Propserpolder levees. Overflow tests on levees are designed to test the strength of levees and levee covers under the load of a continuously overflowing discharge of water. For this purpose, Flanders Hydraulics Research have designed and built an Overflow Generator (Vercruysse et al., 2022) within the framework of the Polder2C’s project. This device allows to generate a controlled and homogenous discharge of water over the levee crest. Within the Polder2C’s project, 27 overflow tests on Belgian and Dutch levee stretches have been executed in 3 episodes from 30/10/20 to 28/11/20, 17/02/21 to 31/03/21 and 16/11/21 to 20/12/21. Different test goals have been addressed, to understand the normal performance of a levee cover, and the influence of different anomalies and/or deviations from the ‘standard’ levee.
DOCUMENT
Modifiable (biomechanical and neuromuscular) anterior cruciate ligament (ACL) injury risk factors have been identified in laboratory settings. These risk factors were subsequently used in ACL injury prevention measures. Due to the lack of ecological validity, the use of on-field data in the ACL injury risk screening is increasingly advocated. Though, the kinematic differences between laboratory and on-field settings have never been investigated. The aim of the present study was to investigate the lower-limb kinematics of female footballers during agility movements performed both in laboratory and football field environments. Twenty-eight healthy young female talented football (soccer) players (14.9 ± 0.9 years) participated. Lower-limb joint kinematics was collected through wearable inertial sensors (Xsens Link) in three conditions: (1) laboratory setting during unanticipated sidestep cutting at 40-50°; on the football pitch (2) football-specific exercises (F-EX) and (3) football games (F-GAME). A hierarchical two-level random effect model in Statistical Parametric Mapping was used to compare joint kinematics among the conditions. Waveform consistency was investigated through Pearson's correlation coefficient and standardized z-score vector. In-lab kinematics differed from the on-field ones, while the latter were similar in overall shape and peaks. Lower sagittal plane range of motion, greater ankle eversion, and pelvic rotation were found for on-field kinematics (p < 0.044). The largest differences were found during landing and weight acceptance. The biomechanical differences between lab and field settings suggest the application of context-related adaptations in female footballers and have implications in ACL injury prevention strategies. Highlights: Talented youth female football players showed kinematical differences between the lab condition and the on-field ones, thus adopting a context-related motor strategy. Lower sagittal plane range of motion, greater ankle eversion, and pelvic rotation were found on the field. Such differences pertain to the ACL injury mechanism and prevention strategies. Preventative training should support the adoption of non-linear motor learning to stimulate greater self-organization and adaptability. It is recommended to test football players in an ecological environment to improve subsequent primary ACL injury prevention programmes.
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Out-of-plane (OOP) collapse is one of the most observed damage types in masonry structures during strong earthquakes. OOP strength of a masonry wall depends on several parameters such as the dimensions of the wall, vertical restoring force, boundary conditions and material properties, which are parameters creating complex kinematics during an earthquake. Testing of OOP response of a masonry wall is thus a challenging task, also because additional to the complexities mentioned, the seismic forces triggering OOP are caused by inertia of the wall itself, a phenomenon that needs dynamic testing. All these facts make shake table tests of masonry walls for capturing the OOP response extremely relevant. This paper presents shake table tests on a total of four wall specimens, two of which were reference walls and the other two were strengthened solid masonry walls. The tested walls built to represent the characteristics of Groningen houses built before the Second World War and also the historical masonry structures in the region. The strengthening methods applied are the deep-mounted carbon strips embedded in flexible epoxy and helical bars applied in mortar beds. The shake table tests presented here show that OOP specimens not including the additional masses imposed by the floors may oversee important kinematic response characteristics of the walls. Furthermore, tests have also shown that even serious cracks caused by OOP response close when the shaking stops, which causes damage on the walls and significant decrease in the stiffness, but they are extremely difficult to be caught by human inspection. This has consequences in terms of ongoing damage inspection and compensation efforts taking place in the Groningen gas field. The strengthening methods applied to the two specimens have shown clear improvement in strength, and a partial improvement in progression of damage.
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Background: Functional Capacity (FC) is a multidimensional construct within the activity domain of the International Classification of Functioning, Disability and Health framework (ICF). Functional capacity evaluations (FCEs) are assessments of work-related FC. The extent to which these work-related FC tests are associated to bio-, psycho-, or social factors is unknown. The aims of this study were to test relationships between FC tests and other ICF factors in a sample of healthy workers, and to determine the amount of statistical variance in FC tests that can be explained by these factors. Methods: A cross sectional study. The sample was comprised of 403 healthy workers who completed material handling FC tests (lifting low, overhead lifting, and carrying) and static work FC tests (overhead working and standing forward bend). The explainable variables were; six muscle strength tests; aerobic capacity test; and questionnaires regarding personal factors (age, gender, body height, body weight, and education), psychological factors (mental health, vitality, and general health perceptions), and social factors (perception of work, physical workloads, sport-, leisure time-, and work-index). A priori construct validity hypotheses were formulated and analyzed by means of correlation coefficients and regression analyses. Results: Moderate correlations were detected between material handling FC tests and muscle strength, gender, body weight, and body height. As for static work FC tests; overhead working correlated fair with aerobic capacity and handgrip strength, and low with the sport-index and perception of work. For standing forward bend FC test, all hypotheses were rejected. The regression model revealed that 61% to 62% of material handling FC tests were explained by physical factors. Five to 15% of static work FC tests were explained by physical and social factors. Conclusions: The current study revealed that, in a sample of healthy workers, material handling FC tests were related to physical factors but not to the psychosocial factors measured in this study. The construct of static work FC tests remained largely unexplained.
LINK
This study evaluates the maximum theoretical exposure to radiofrequency (RF) electromag- netic fields (EMFs) from a Fifth-generation (5G) New Radio (NR) base station (BS) while using four commonly used mobile applications: YouTube for video streaming, WhatsApp for voice calls, Instagram for posting pictures and videos, and running a Video game. Three factors that might affect exposure, i.e., distance of the measurement positions from the BS, measurement time, and induced traffic, were examined. Exposure was assessed through both instantaneous and time-averaged extrapolated field strengths using the Maximum Power Extrapolation (MPE) method. The former was calculated for every measured SS-RSRP (Secondary Synchronization Reference Signal Received Power) power sample obtained with a sampling resolution of 1 second, whereas the latter was obtained using a 1-min moving average applied on the applications’ instantaneous extrapolated field strengths datasets. Regarding distance, two measurement positions (MPs) were selected: MP1 at 56 meters and MP2 at 170 meters. Next, considering the measurement time, all mobile application tests were initially set to run for 30 minutes at both MPs, whereas the video streaming test (YouTube) was run for an additional 150 minutes to investigate the temporal evolution of field strengths. Considering the traffic, throughput data vs. both instantaneous and time-averaged extrapolated field strengths were observed for all four mobile applications. In addition, at MP1, a 30-minute test without a User Equipment (UE) device was conducted to analyze exposure levels in the absence of induced traffic. The findings indicated that the estimated field strengths for mobile applications varied. It was observed that distance and time had a more significant impact than the volume of data traffic generated (throughput). Notably, the exposure levels in all tests were considerably lower than the public exposure thresholds set by the ICNIRP guidelines.INDEX TERMS 5G NR, C-band, human exposure assessment, mobile applications, traffic data, maximum extrapolation method, RF-EMF.
MULTIFILE
Supplemental Instruction (SI) is a form of structured peer guidance attached to a specific course, provided by an experienced and trained student to a group of students. Previous studies show a positive effect of SI on learning outcomes, some found effects on well-being, and sense of belonging. However, literature on SI lacks randomized controlled trials and does not fully address the risk of self-selection bias. The current study tested whether SI has an effect on grades, mental well-being, and sense of belonging with a pre-registered randomized field experiment and a sample of 493 Dutch first-year students. Students who were offered SI obtained significantly higher grades (d = 0.26) but did not score significantly different on mental well-being or belonging.
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