Abstract
The calibrations or checking of mass standards with nominal values greater than 10 kg and high accuracy class require special attention to the environmental conditions stability due to the ...their volume. The equipment used to calibrate this kind of mass standards usually has a weighing chamber (in this case a glass campanula or bell jar) to avoid, at least to reduce, the effects of environmental changes. In this study will be present the effects of these weighing campanulas on the standard deviations and in mass measurements results using only the internal tare (without weights in the balance plate) and using two 10 kg test weights.
The results of investigations of metrological characteristics of reference installations based on the helium pycnometry and hydrostatic weighing methods are demonstrated.
Extrapolation and bubbles Barberis, Nicholas; Greenwood, Robin; Jin, Lawrence ...
Journal of financial economics,
08/2018, Letnik:
129, Številka:
2
Journal Article
Recenzirano
Odprti dostop
We present an extrapolative model of bubbles. In the model, many investors form their demand for a risky asset by weighing two signals—an average of the asset’s past price changes and the asset’s ...degree of overvaluation—and “waver” over time in the relative weight they put on them. The model predicts that good news about fundamentals can trigger large price bubbles, that bubbles will be accompanied by high trading volume, and that volume increases with past asset returns. We present empirical evidence that bears on some of the model’s distinctive predictions.
•Open weighing increases anxiety and preoccupation with weight control behaviours.•Blind weighing reduces anxiety and overconcern with weight.•Both forms of weighing increase weight preoccupation and ...disordered behaviours.•Blind weighing, although not completely benign, may be safer than open weighing.
Regular weighing is a routine component of public health interventions but concerns have been raised about possible negative psychological consequences. Blind weighing is an alternative form of weighing that is commonly used in clinical contexts, and that is thought to decrease weighing anxiety and engagement with disordered eating behaviours. In this study, normal weight female participants who indicated a high drive for thinness (N = 53) were randomly assigned to receive bi-weekly open or blind weighing for three weeks. Participants who were open weighed felt increasingly anxious over time, whereas participants who were blind weighed felt less anxious. Both groups experienced increased weight preoccupation and disordered eating behaviours on weighing days compared to non-weighing days. Analyses of participants’ qualitative responses further indicated that open weighed participants experienced increased urges to engage in weight-controlling behaviours throughout the experiment whereas blind weighed participants reported reduced concern with weight. Findings suggest that blind weighing may be a safer approach to weight monitoring, even though weighing in both forms can have a (transient) negative effect. Future research should evaluate whether the current findings are generalisable for other subgroups of the population.
Weight of cows affects a large number of factors. Regular weighing and data processing can detect differences that may indicate disorders requiring nursing interventions, e.g. nutritional ...deficiencies, incorrect fetal development and health problems. The current weighing systems operate as stationary - the animal is fixed, identified and weighed. However, the procedure is time consuming and operation, and that is way this system is used minimally. That implies the need of complete automation of all activities associated with the weighing, which enables introduction of pass – through weight. The aim of this thesis was to develop a methodology for evaluating health and nutritional status of the herd based on data from an automated system for weighing a live weight of dairy cows. There was used in the weighing unit for milking robots Astronaut A3 (Lely company) to obtain weight data of individual cows. There were selected dairy cows with the longest period of lactation or already drying off, and especially dairy cows with various health problems for study. Limiting values of weight changes were established after assembling a general equation of mass curve. In the sphere of the diseases there was manifested only ketosis in the weight curve with a loss of 10.2 kg / day (38% weight loss). Additionally, the completion of growth during the first 2 periodes of lactations and weight gain due to advanced pregnancy were confirmed. The maximum daily weight difference recorded in healthy animals was 7 %, equivalent to 40 - 45 kg. The results of the study will be applied for compiling algorithm that will be implemented in the complete management system of cattle breeding, monitoring the dairy cows every day and highlight possible deviations exceeding of physiological changes in weight.
Abstract
This paper introduces a kind of on-line calibration facility based on weighing method and master meter method, which can carry out the on-site and laboratory calibration of 35MPa/70MPa ...hydrogen dispenser. At first, the working principle and technical specifications of the hydrogen dispenser is explained. Then the working principle and design structure of the calibration facility is depicted. Finally, the calibration facility is used to perform the real flow calibration test on hydrogen dispenser. According to the test results, the expanded uncertainty of the calibration facility of master meter method is about 0.7% (k=2), and the expanded uncertainty of the calibration result is 0.96% (k=2); and the expanded uncertainty of calibration facility of weighing method is about 0.097% (k=2), and the expanded uncertainty of calibration result is 0.48% (k=2). The real flow test shows that the two method calibration facilities both can be used for actual calibration of 2.5-level hydrogen dispenser. The calibration facility of weighing method is suitable for the occasions with high accuracy requirements because of its short traceability chain, while the calibration facility of master meter method can be used for flexible on-line calibration because of its simple structure.
We have applied our method to weigh the Galactic disk using phase-space spirals to the proper motion sample of Gaia’s early third release (EDR3). For stars in distant regions of the Galactic disk, ...the latitudinal proper motion has a close projection with vertical velocity, such that the phase-space spiral in the plane of vertical position and vertical velocity can be observed without requiring that all stars have available radial velocity information. We divided the Galactic plane into 360 separate data samples, each corresponding to an area cell in the Galactic plane in the distance range of 1.4–3.4 kpc, with an approximate cell length of 200–400 pc. Roughly half of our data samples were disqualified altogether due to severe selection effects, especially in the direction of the Galactic centre. In the remainder, we were able to infer the vertical gravitational potential by fitting an analytic model of the phase-space spiral to the data. This work is the first of its kind, in the sense that we are weighing distant regions of the Galactic disk with a high spatial resolution, without relying on the strong assumptions of axisymmetry. Post-inference, we fitted a thin disk scale length of 2.2 ± 0.1 kpc, although this value is sensitive to the considered spatial region. We see surface density variations as a function of azimuth of the order of 10–20%, which is roughly the size of our estimated sum of potential systematic biases. With this work, we have demonstrated that our method can be used to weigh distant regions of the Galactic disk despite strong selection effects. We expect to reach even greater distances and improve our accuracy with future Gaia data releases and further improvements to our method.
Balanced weighing matrices Kharaghani, Hadi; Pender, Thomas; Suda, Sho
Journal of combinatorial theory. Series A,
February 2022, 2022-02-00, Letnik:
186
Journal Article
Recenzirano
A unified approach to the construction of weighing matrices and certain symmetric designs is presented. Assuming the weight p in a weighing matrix W(n,p) is an odd prime power, it is shown that there ...is aW(pm+1−1p−1(n−1)+1,pm+1) for each positive integer m. The case of n=p+1 reduces to the balanced weighing matrices with classical parametersW(pm+2−1p−1,pm+1). The equivalence with certain classes of association schemes is discussed in detail.
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