As Time Goes By: Ritualized Remembering Through Wedding Photography

The practice of remembering sometimes takes the form of ritual in order to enforce, embody and sustain social bonds and values. American wedding photography is a strong example of an instance in which remembering becomes a formalized symbolic performance through an intricate system of idealization as prescribed by various authorities. An examination of the production and exhibition practices constituting wedding photography (using various interview and observation methodologies) reveals a process through which participants solidify and maintain the social transformation marriage creates, communicate values to future generations, and cope with the implications of aging and death

Carbon nanotube-guided thermopower waves

Thermopower waves are a new concept for the direct conversion of chemical to electrical energy. A nanowire with large axial thermal diffusivity can accelerate a self-propagating reaction wave using a fuel coated along its length. The reaction wave drives electrical carriers in a thermopower wave, creating a high-power pulse of as much as 7 kW/kg in experiments using carbon nanotubes. We review nanomaterials designed to overcome limitations of thermoelectricity and explore the emerging scientific and practical outlook for devices using thermopower waves

Extrusion Additive Manufacturing of PEI Pellets

The simplest, most cost-efficient, and most widespread Additive Manufacturing (AM) technology is Extrusion Additive Manufacturing (EAM). Usually, EAM is performed with filament feedstock, but using pellets instead of filaments yields many benefits, including significantly lower cost and a wider choice of materials. High-performance polymers offer high strength even when produced with AM technique, allowing to produce near-net-shape functional parts. The production of these materials in filament form is still limited and expensive; therefore, in this paper, the possibility of producing AM components with engineering polymers from pellets will be thoroughly investigated. In this work, the effectiveness of a specially designed AM machine for printing high-performance materials in pellet form was tested. The material chosen for the investigation is PEI 1000 which offers outstanding mechanical and thermal properties, giving the possibility to produce with EAM functional components. Sensitivity analyses have been carried out to define a process window in terms of thermal process parameters by observing different response variables. Using the process parameters in the specified range, the additive manufactured material has been mechanically tested, and its microstructure has been investigated, both in dried and undried conditions. Finally, a rapid tool for sheet metal forming has been produced

Hierarchical metamodeling: Cross validation and predictive uncertainty

At Esaform 2013 a hierarchical metamodeling approach had been presented, able to com- bine the results of numerical simulations and physical experiments into a unique response surface, which is a "fusion'' of both data sets. The method had been presented with respect to the structural optimization of a steel tube, filled with an aluminium foam, intended as an anti-intrusion bar. The prediction yielded by a conventional way of metamodeling the results of FEM simulations can be considered trustworthy only if the accuracy of numerical models have been thoroughly tested and the simulation parameters have been sufficiently calibrated. On the contrary, the main advantage of a hierarchical metamodel is to yield a reliable prediction of a response variable to be optimized, even in the presence of non-completely calibrated or accurate FEM models. In order to demonstrate these statements, in this paper the authors wish to compare the prediction ability of a "fusion'' metamodel based on under-calibrated simulations, with a conventional approach based on calibratedFEMresults. Both metamodels will be cross validated with a "leave-one-out'' technique, i.e. by excluding one ex- perimental observation at a time and assessing the predictive ability of the model. Furthermore, the paper will demonstrate how the hierarchical metamodel is able to provide not only an average esti- mated value for each excluded experimental observation, but also an estimation of uncertainty of the prediction of the average value

Energy Efficiency of the Vulcanization Process of a Bicycle Tyre

The production of tyres is one of the most energy consuming manufacturing activities in the rubber sector. In the production cycle of a tyre, the curing operation has the maximum energy loss. This is mostly due to the extensive use of steam as a source of heat and pressure in the vulcanization process. To the author’s knowledge, no scientific work is available in the literature where the energy efficiency of a tyre vulcanization press is estimated by means of a comprehensive model of all main components, including the moulds, the press with its heated plates, the bladder and, of course, the tyre. The present work aims at filling this gap. First, the press used for developing the model is described, along with its components and its typical product, a bicycle tyre. The instruments used for measuring flow rates, temperatures and pressures are also listed. Then, a numerical model is presented, that predicts the energy transfers occurring in the vulcanization press during a full process cycle. The numerical model, developed with the software Simcenter Amesim 2021.1, has been validated by means of measurements taken at the press. The results indicate that the amount of energy which is actually consumed by the tyre for its reticulation process amounts to less than 1% of the total energy expenditure. The paper demonstrates that the tyre industry is in urgent need of an electrification conversion of the traditional steam-based processes

The Structure of Spatial Networks and Communities in Bicycle Sharing Systems

Bicycle sharing systems exist in hundreds of cities around the world, with the aim of providing a form of public transport with the associated health and environmental benefits of cycling without the burden of private ownership and maintenance. Five cities have provided research data on the journeys (start and end time and location) taking place in their bicycle sharing system. In this paper, we employ visualization, descriptive statistics and spatial and network analysis tools to explore system usage in these cities, using techniques to investigate features specific to the unique geographies of each, and uncovering similarities between different systems. Journey displacement analysis demonstrates similar journey distances across the cities sampled, and the (out)strength rank curve for the top 50 stands in each city displays a similar scaling law for each. Community detection in the derived network can identify local pockets of use, and spatial network corrections provide the opportunity for insight above and beyond proximity/popularity correlations predicted by simple spatial interaction models

iObjectify: self- and other-objectification on Grindr, a geosocial networking application designed for men who have sex with men

Grindr is a smartphone application for men who have sex with men (MSM). Despite its reputation as a ‘hook-up app’, little is known about its users’ self-presentation strategies and how this relates to objectification - this paper explores objectification on Grindr. The results of Study 1 showed that Grindr users objectified other men more than non-Grindr users. A content analysis of 1400 Grindr profiles in Study 2 showed that profile pictures with objectifying content were related to searching for sexual encounters. Finally, a survey of Grindr users in Study 3 revealed that objectification processes and sexualized profile pictures were related to some objectification-relevant online behaviors (e.g., increased use of Grindr, discussion of HIV status). Interestingly, the presence of body focused profile content was more related to sexual orientation disclosure (not being ‘out’) than to objectification. This paper presents evidence that Grindr usage and online presentation are related to objectification processes

In Vivo Delivery of Nitric Oxide-Sensing, Single-Walled Carbon Nanotubes

Detection of nitric oxide (NO) in vivo by single-walled carbon nanotubes (SWNT) is based on the fluorescent properties of SWNT and the ability of NO to quench the fluorescence signal. Alterations of the signal can be utilized to detect a small molecule in vivo that has not previously been possible by other assay techniques. The protocols described here explain the techniques used to prepare NO-detecting SWNTs and to administer them to mice by both intravenous and subcutaneous routes. These techniques can also be utilized with other SWNT sensors as well as non-SWNT sensorNational Institutes of Health (T32 Training Grant in Environmental Toxicology ES007020

Extraordinary sensitivity of the electronic structure and properties of single-walled carbon nanotubes to molecular charge-transfer

Interaction of single-walled carbon nanotubes with electron donor and acceptor molecules causes significant changes in the electronic and Raman spectra, the relative proportion of the metallic species increasing on electron donation through molecular charge transfer, as also verified by electrical resistivity measurements.Comment: 15 pages, 5 figurre

Design and Development of an Innovative E-Bike☆

Abstract A new model of power-assisted bicycle has been designed, set up and tested. The main innovative solutions for the pedelec prototype are described in the present paper: the electric motor position; the new mechanical transmission; the low cost measurement system of the driving torque; the special test rig. Differently from a common approach, in which the electric motor is located on one of the three hubs of the bicycle, the idea of the pedelec prototype consists of an electrical motor in the central position that, by means of a bevel gear, transmits the torque on the central hub. The other innovative solution is represented by the motion transmission from the motor to the pedal shaft, achieved by two different gearboxes: the first one is a planetary gearbox and the second one is a simple bevel gear. The pedelec prototype contains also a new low cost measurement system of the driving torque based on a strain gauge load cell located on one side of the rear wheel, between the hub and the frame. Moreover, a commercial cycling simulator has been suitably modified in order to properly install the different sensors for the measurement of the performance of the pedelec. The test rig is able to reproduce an aforethought route or paths acquired during road tests, to measure the performance of the e-bike in terms of instantaneous power and speed. The experimental test rig can simulate the resistant torque of a predetermined track and it aims to test and to optimize the control strategy available on the electronic control unit. The authors have also conducted an environmental analysis of the developed pedelec, in particular comparing the e-bike with a thermal moped, in terms of environmental impact