Search results for "C1"
showing 10 items of 3475 documents
Electronic Energy Meter Based on a Tunnel Magnetoresistive Effect (TMR) Current Sensor
2017
In the present work, the design and microfabrication of a tunneling magnetoresistance (TMR) electrical current sensor is presented. After its physical and electrical characterization, a wattmeter is developed to determine the active power delivered to a load from the AC 50/60 Hz mains line. Experimental results are shown up to 1000 W of power load. A relative uncertainty of less than 1.5% with resistive load and less than 1% with capacitive load was obtained. The described application is an example of how TMR sensing technology can play a relevant role in the management and control of electrical energy.
Patterning of supported gold monolayers via chemical lift-off lithography
2017
The supported monolayer of Au that accompanies alkanethiolate molecules removed by polymer stamps during chemical lift-off lithography is a scarcely studied hybrid material. We show that these Au–alkanethiolate layers on poly(dimethylsiloxane) (PDMS) are transparent, functional, hybrid interfaces that can be patterned over nanometer, micrometer, and millimeter length scales. Unlike other ultrathin Au films and nanoparticles, lifted-off Au–alkanethiolate thin films lack a measurable optical signature. We therefore devised fabrication, characterization, and simulation strategies by which to interrogate the nanoscale structure, chemical functionality, stoichiometry, and spectral signature of t…
Prompt Determination of the Mechanical Properties of Industrial Polypropylene Sandwich Pipes
2021
A simple and prompt method to determine the mechanical properties of industrial multilayer extrusion polypropylene pipes for a gravity sewer network is suggested. The engineering formulas included for calculating the permissible thickness and relative position of a foam core in the pipes are based on a linear-elastic approximation and the rule of mixtures. The applicability of the approximation was justified experimentally during investigation of the effective tensile characteristics of single- and multilayer pipes and each layer specimen by using traditional tests and finite-element calculations. The results obtained were used to formulate engineering recommendations for calculations of th…
Ultra-High Energy Neutrinos at the Pierre Auger Observatory
2013
The observation of ultrahigh energy neutrinos (UHE nu s) has become a priority in experimental astroparticle physics. UHE nu s can be detected with a variety of techniques. In particular, neutrinos can interact in the atmosphere (downward-going nu) or in the Earth crust (Earth-skimming nu), producing air showers that can be observed with arrays of detectors at the ground. With the surface detector array of the Pierre Auger Observatory we can detect these types of cascades. The distinguishing signature for neutrino events is the presence of very inclined showers produced close to the ground (i.e., after having traversed a large amount of atmosphere). In this work we review the procedure and …
Elementos ideológicos en las unidades fraseológicas con la palabra mujer en el Diccionario académico en los siglos XVIII y XIX
2017
This paper explores ideological elements regarding gender in phraseological units with the word mujer(‘woman’) in the different editions of the dictionarypublished by Real Academia Española during the 18th and the 19th centuries. First, the ideological content in the phraseological units themselves is analyzed. Second, phenomena related to subjectivity in the definitions are analyzed: this evidences subjectivity not only in the different phraseological units presented in the dictionary, but also in the discourse of the academics. In order to approach the first issue, a typology of the different phraseological units according to their syntactic-semantic properties is provided: this categoriz…
Contrasts in fitness, motor competence and physical activity among children involved in single or multiple sports
2021
Abstract Study aim: While there is wide debate around specialization in one sport, there is a lack of information about fitness levels and motor competence of children participating in single or multiple sports. Material and methods: The study involved 358 fifth-grade children who participated in a set of health-related fitness and motor competence tests over two consecutive years. A subsample of children (n = 109) wore an accelerometer for seven consecutive days. The independent samples t-test and ANCOVA were used to compare differences between single and multi-sport participants in study variables and changes between baseline and follow-up. Results: Multi-sport participants performed bett…
Tendon length estimates are influenced by tracking location
2022
Abstract Purpose Measurement of medial gastrocnemius (MG) tendon length using ultrasonography (US) requires the muscle–tendon junction (MTJ) to be located. Previously, the MG MTJ has been tracked from different proximo-distal locations near the MTJ, which could influence estimates of tendon length change due to the different characteristics of the aponeurosis and tendon. We used US to evaluate the effect of tracking point location on MG MTJ displacement during maximal and submaximal (10, 20 and 30% of the non-injured maximal) isometric plantar flexion contractions. Methods Displacement behaviour of MTJ was tracked from (1) the exact MTJ; and (2) from an insertion point of a muscle fascicle …
A New Reliable Performance Analysis Template for Quantifying Action Variables in Elite Men’s Wheelchair Basketball
2019
This study aimed to develop a valid and reliable performance analysis template for quantifying team action variables in elite men’s wheelchair basketball. First action variables and operational definitions were identified by the authors and verified by an expert panel of wheelchair basketball coaching staff in order to establish expert validity. A total of 109 action variable were then placed into 17 agreed Categorical Predictor Variable categories. The action variables were then used to develop a computerized performance analysis template for post-event analysis. Each possession (n = 200) from an international men’s wheelchair basketball game was analyzed by the first author on two occasio…
Aposematism in the burying beetle? Dual function of anal fluid in parental care and chemical defence
2017
Burying beetles (Nicrophorus vespilloides) bear distinctive and variable orange-black patterning on their elytra and produce an anal exudate from their abdomen when threatened. During breeding, the anal exudates contribute to the antimicrobial defence of the breeding resource. We investigated whether the anal exudates also provide a responsive chemical defence, which is advertised to potential avian predators by the beetle’s orange and black elytral markings. We found that that the orange-black elytral markings of the burying beetle are highly conspicuous for avian predators against range of backgrounds, by using computer simulations. Using bioassays with wood ants, we also showed that the …
Numerical Simulations of the Flow Field of a Submerged Hydraulic Jump over Triangular Macroroughnesses
2021
The submerged hydraulic jump is a sudden change from the supercritical to subcritical flow, specified by strong turbulence, air entrainment and energy loss. Despite recent studies, hydraulic jump characteristics in smooth and rough beds, the turbulence, the mean velocity and the flow patterns in the cavity region of a submerged hydraulic jump in the rough beds, especially in the case of triangular macroroughnesses, are not completely understood. The objective of this paper was to numerically investigate via the FLOW-3D model the effects of triangular macroroughnesses on the characteristics of submerged jump, including the longitudinal profile of streamlines, flow patterns in the cavity regi…