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Data sets for "Structure of alkali magnesium, zinc, and calcium metasilicate glasses"
No full textData sets used to prepare Figures 5-14 in the Journal of Chemical Physics article entitled "Structure of alkali magnesium, zinc, and calcium metasilicate glasses." The data sets describe the structure of the metasilicate composition glasses (A2O)_x(XO)_{0.50-x}(SiO2)_{0.50}, with A = Na or K, X = Mg, Zn or Ca, and x = 0.25 or 0.33, as measured using neutron and high-energy x-ray diffraction and 25Mg solid-state nuclear magnetic resonance spectroscopy
Deep recurrent-convolutional neural network learning and physics Kalman filtering comparison in dynamic load identification
Get PDFThe dynamic structural load identification capabilities of the gated recurrent unit, long short-term memory, and convolutional neural networks are examined herein. The examination is on realistic small dataset training conditions and on a comparative view to the physics-based residual Kalman filter (RKF). The dynamic load identification suffers from the uncertainty related to obtaining poor predictions when in civil engineering applications only a low number of tests are performed or are available, or when the structural model is unidentifiable. In considering the methods, first, a simulated structure is investigated under a shaker excitation at the top floor. Second, a building in California is investigated under seismic base excitation, which results in loading for all degrees of freedom. Finally, the International Association for Structural Control-American Society of Civil Engineers (IASC-ASCE) structural health monitoring benchmark problem is examined for impact and instant loading conditions. Importantly, the methods are shown to outperform each other on different loading scenarios, while the RKF is shown to outperform the networks in physically parametrized identifiable cases
Reference Dependence and Lottery Participation
Get PDFWe assume that lottery participants are poor relative to their target income. Reference dependence with loss aversion can render the marginal utility of income non-monotonic in line with the Friedman-Savage hypothesis. As a result, lottery participation can be rational without probability weighting. Our theoretical predictions are consistent with the latest empirical evidence on lottery spending
Agency of silence:Female Syrian refugee workers and the reconstitution of the post-war self
Get PDFThis study explores the working lives of female refugees who, living in the backstreets of major cities in the Global South, are often inaccessible to research. Most were housewives before their exile but must now find paid work to support their children. This ethnographic study shows that the only employment available to these women is domestic work and cleaning – occupations that are doubly stigmatised in their tradition and threaten their desire to rebuild honourable selves destroyed by war and displacement. Drawing on the work of the poststructuralist anthropologist Saba Mahmood, I argue that these refugee women reconstitute honourable selves through the agency of silence. I illustrate how, through agentive practices of silence – such as invisibility, concealment, renaming and refusal to speak – these female refugees protect their deeply desired valorised status while performing stigmatised work. In exploring the reconstitution of the honourable post-war self through the agency of silence, this study (i) makes a feminist contribution to the emerging field of refugee studies within management thought by extending understanding of female refugee agency in the Global South and (ii) develops the theory of the agency of silence that enables the reconstitution of the self, thereby advancing scholarship on organisational silence
Accounting for ceiling effects in gender equality endorsement. A zero inflated modeling approach.
Get PDFGender equality endorsement is an intergroup measure present in various survey-based studies and is a prominent indicator among the Sustainable Developmental Goals (SDG) (Sandoval-Hernández et al., 2020). To this end, countries can rely on the gender equality endorsement scale included in the International Civic and Citizenship Study (ICCS), which provides probabilistic samples of 8th-grade students from different countries and assesses gender equality endorsement between men and women. Traditional methods for generating scores with this scale rely on the partial credit model (PCM), a response model that utilizes a normally distributed latent variable to represent students' propensity to respond to the various items included in the instrument. Moreover, researchers rely on regression models to address research questions about related factors and the effects of program evaluation. However, the scale scores of this instrument are highly skewed. This skewness is desirable. It means a noticeable portion of students endorse gender equality at the scale ceiling. Nevertheless, traditional regression models may produce distorted estimates in the presence of ceiling effects on the total scores. We propose a method that relies on the monotonicity property of the PCM scores and creates a reverse sum score. We use zero-inflated models to separate ceiling cases from the rest of the scores, allowing us to make inferences on both sides: the students at the ceiling and those in the remainder of the distribution. This method is a helpful tool for program evaluations dealing with ceiling effects in their attribute of interest
Improving National and International Surveillance of Movement Behaviours in Childhood and Adolescence:An International Modified Delphi Study
Get PDFBACKGROUND: The actions required to achieve higher-quality and harmonised global surveillance of child and adolescent movement behaviours (physical activity, sedentary behaviour including screen time, sleep) are unclear.OBJECTIVE: To identify how to improve surveillance of movement behaviours, from the perspective of experts.METHODS: This Delphi Study involved 62 experts from the SUNRISE International Study of Movement Behaviours in the Early Years and Active Healthy Kids Global Alliance (AHKGA). Two survey rounds were used, with items categorised under: (1) funding, (2) capacity building, (3) methods, and (4) other issues (e.g., policymaker awareness of relevant WHO Guidelines and Strategies). Expert participants ranked 40 items on a five-point Likert scale from 'extremely' to 'not at all' important. Consensus was defined as > 70% rating of 'extremely' or 'very' important.RESULTS: We received 62 responses to round 1 of the survey and 59 to round 2. There was consensus for most items. The two highest rated round 2 items in each category were the following; for funding (1) it was greater funding for surveillance and public funding of surveillance; for capacity building (2) it was increased human capacity for surveillance (e.g. knowledge, skills) and regional or global partnerships to support national surveillance; for methods (3) it was standard protocols for surveillance measures and improved measurement method for screen time; and for other issues (4) it was greater awareness of physical activity guidelines and strategies from WHO and greater awareness of the importance of surveillance for NCD prevention. We generally found no significant differences in priorities between low-middle-income (n = 29) and high-income countries (n = 30) or between SUNRISE (n = 20), AHKGA (n = 26) or both (n = 13) initiatives. There was a lack of agreement on using private funding for surveillance or surveillance research.CONCLUSIONS: This study provides a prioritised and international consensus list of actions required to improve surveillance of movement behaviours in children and adolescents globally.</p
Signaling Quality:How Refund Bonuses Can Overcome Information Asymmetries in Crowdfunding
Get PDFCrowdfunding can suffer from information asymmetry, leaving some investors disappointed with low-quality projects, whereas other high-quality projects remain unfunded. We show that refund bonuses, which provide investors a payment if a fundraising campaign is unsuccessful, can signal project quality and help overcome the market failure in crowdfunding. Because strong projects have a lower risk of bonus payout, entrepreneurs with strong projects are more likely to offer bonuses. This signals high quality to investors, and due to their updated beliefs, this drives investment toward such projects. An experiment provides supporting empirical evidence for the benefits of this signaling solution to the problems of information asymmetry in crowdfunding
Mass and Heat Exchange in Rotating Compressor Cavities With Variable Cob Separation
Get PDFNext generation aeroengines will operate at ever-increasing pressure ratios with smaller cores, where the control of blade-tip clearances across the flight cycle is an emerging design challenge. Such clearances are affected by the thermal expansion of the compressor disks that hold the blades, where acute thermal stresses govern operating life. The cavities formed by corotating disks feature a heated shroud at high radius and cooler cobs at low radius. A three-dimensional, unsteady and unstable flow structure is induced by destabilizing buoyancy forces. The radial distribution of disk temperature is driven by a conjugate heat transfer at Grashof numbers of order 10 13. Such flows are further influenced by the heat and mass exchange with an axial throughflow of cooling air at low radius, where the interaction depends on the Rossby number and separation of the disk cobs. This paper is the first to study the effect of cob separation ratio on mass and heat exchange for compressor cavities. A model is developed to predict the cavity-throughflow interaction, and disk and fluid-core temperatures. The judicious use of a physics-based methodology provides reliable, reduced-order solutions to the complex conjugate problem, thereby making it appropriate for practical engine thermo-mechanical design. The model is validated by detailed experimental measurements using the Bath Compressor Cavity Rig, where variable disk cob spacings were investigated over a range of engine-representative conditions. The unsteady pressure measurements collected in the frame of reference of the rotating disks reveal new insight into the fundamentally aperiodic nature of the flow structure. This new understanding of heat transfer informs an expedient reduced-order model and enables more efficient design of future high pressure-ratio aeroengines.</p
Mass and Heat Exchange in Rotating Compressor Cavities With Variable Cob Separation
Get PDFNext generation aeroengines will operate at ever-increasing pressure ratios with smaller cores, where the control of blade-tip clearances across the flight cycle is an emerging design challenge. Such clearances are affected by the thermal expansion of the compressor disks that hold the blades, where acute thermal stresses govern operating life. The cavities formed by corotating disks feature a heated shroud at high radius and cooler cobs at low radius. A three-dimensional, unsteady and unstable flow structure is induced by destabilizing buoyancy forces. The radial distribution of disk temperature is driven by a conjugate heat transfer at Grashof numbers of order 10 13. Such flows are further influenced by the heat and mass exchange with an axial throughflow of cooling air at low radius, where the interaction depends on the Rossby number and separation of the disk cobs. This paper is the first to study the effect of cob separation ratio on mass and heat exchange for compressor cavities. A model is developed to predict the cavity-throughflow interaction, and disk and fluid-core temperatures. The judicious use of a physics-based methodology provides reliable, reduced-order solutions to the complex conjugate problem, thereby making it appropriate for practical engine thermo-mechanical design. The model is validated by detailed experimental measurements using the Bath Compressor Cavity Rig, where variable disk cob spacings were investigated over a range of engine-representative conditions. The unsteady pressure measurements collected in the frame of reference of the rotating disks reveal new insight into the fundamentally aperiodic nature of the flow structure. This new understanding of heat transfer informs an expedient reduced-order model and enables more efficient design of future high pressure-ratio aeroengines.</p
Fair Value Distribution in Cooperative Committee Election
Get PDFWe consider a scenario where a group of agents needs to elect a committee to lead them in accomplishing a project. They elect a committee to maximize social welfare, and the question is how to distribute the total value of the project to every agent. This scenario encodes a cooperative game setting where the reward of the chosen coalition must be distributed fairly. First, we establish the axiomatic foundation of solution concepts in this cooperative committee election game. We show that a natural extension of Shapley value to this game does not meet the classical axioms when the values of different coalitions are binary. We then propose a value distribution rule that satisfies all the desired properties. Furthermore, we prove that this rule is unique in meeting these properties and also satisfies an additional monotonicity property. When the values of the coalitions can take any general values, we decompose the game into a linear combination of simple games. This decomposition is unique, allowing us to extend our value distribution rule to solve this general class of games.</p
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