Search results for "Energy absorption"

The importance of thermal history: costs and benefits of heat exposure in a tropical, rocky shore oyster.

2015

Although thermal performance is widely recognized to be pivotal in determining species' distributions, assessment of this performance is often based on laboratory acclimated individuals, neglecting their proximate thermal history. The thermal history of a species sums the evolutionary history and, importantly, the thermal events recently experienced by individuals, including short-term acclimation to environmental variations. Thermal history is perhaps of greatest importance for species inhabiting thermally challenging environments and therefore assumed to be living close to their thermal limits, such as in the tropics. To test the importance of thermal history the responses of the tropical…

Effects of mat characteristics on plantar pressure patterns and perceived mat properties during landing in gymnastics.

2011

Shock absorption and stability during landings is provided by both, gymnast ability and mat properties. The aims of this study were to determine the influence of different mat constructions on their energy absorption and stability capabilities, and to analyse how these properties affect gymnast's plantar pressures as well as subjective mat perception during landing. Six mats were tested using a standard mechanical drop test. In addition, plantar pressures and subjective perception during landing were obtained from 15 expert gymnasts. The different mats influenced plantar pressures and gymnasts' subjective perception during landing of gymnasts. Significant correlations between plantar pressu…

ESR response to gamma-rays of alanine pellets containing B(OH)3 or Gd2O3.

2007

ESR response to gamma-irradiation (1-50 Gy) of blends containing alanine and either B(OH)(3) or Gd(2)O(3) is reported. The sensitivity of the alanine--B(OH)(3) blend is comparable to the sensitivity of pure alanine, although its lowest detectable dose, LDD, is smaller ( approximately 1.3 Gy) than that of pure alanine ( approximately 2.9 Gy). Alanine with Gd(2)O(3) is about two times more sensitive than pure alanine, and its LDD is 0.8 Gy. The better sensitivity and LDD are probably due to the high atomic number (Z=64) of gadolinium, which enhances the interaction probability with photons and, consequently, the radical yield. This study suggests that other high-Z atoms may be useful for incr…

A comparative evaluation of crashworthy composite sandwich structures

2007

Abstract This paper describes an experimental evaluation of the energy absorption properties of a series of novel designs for cost-effective crashworthy composite sandwich structures. All the designs are based on the concept of the “tied-core” sandwich, i.e. the use of additional core reinforcements that act to tie the opposing facings of a sandwich together, thus preventing catastrophic failure under edgewise loading. The design, manufacture and crush testing of hollow rectangular tubes fabricated from six different tied-core concepts is described. Factors that are shown to promote high energy absorption include large, continuous areas of contact between the facings and the ties, non-thin …

Integrazione di celle solari di terza generazione nel vetromattone per la realizzazione di pannelli traslucidi fotovoltaici. Analisi prestazione e st…

2013

L’articolo illustra i primi risultati ottenuti nell’ambito dell’analisi prestazionale del vetromattone fotovoltaico, un prodotto edilizio innovativo derivato dall’integrazione di celle fotovoltaiche di terza generazione (DSSC) nel vetromattone, ideato per la realizzazione di involucri traslucidi energeticamente effi cienti ed “attivi”, in grado di ridurre i consumi energetici degli edifi ci e di produrre, al contempo, energia verde. L’analisi è stata condotta su quattro differenti ipotesi di integrazione. Attraverso simulazioni numeriche si è effettuata una valutazione dell’energia assorbita dagli strati attivi oltre che delle prestazioni ottiche complessive del dispositivo. Lo studio anali…

Theoretical and Experimental Researches Regarding Multilayer Materials Used for Incremental Forming

2014

Although this represents a relatively recent development in the industry, the composite multilayer sheets are currently encountered in almost all industrial domains, due to the density, mechanical strength and energy absorption properties that are higher than those of the blanks realised from a single material. These materials are useful especially in domains such a the automotive industry, where the vehicles must fulfil simultaneously conditions of increased passenger safety, increased comfort, increase of the loading capacity in conditions of a reduced energy consumption. First of all the paper shows the types of multilayer sheets and their areas and areas of use, then the paper analyzes …

Comparison of impact characteristics of four different ice hockey arena dasher boards

2012

During recent years the incidence of ice hockey related concussions has increased. Therefore, the main aim of this study was to determine how dasher board materials and structures affect impact characteristics and thereby concussion risk. The measurements were divided into two parts; 1. physiological characteristics of body checks were determined in real game measurements, and 2. simulation of body checks in the laboratory. Peak forces and stopping distances were determined from the high-speed camera data, and stiffness values were subsequently calculated. Dasher board materials and structures had a clear effect on impact characteristics. Flexible protective shielding material resulted in 1…

Modeling moderated proportional neutron counters using the Geant4 toolkit and the application to detection of fast neutron burst

2014

Role of intermediate species in the formation of ion tracks in PADC: A review

2019

Abstract This review paper intends at identifying the early processes arising during the formation of a latent ion track in Poly Allyl Diglycol Carbonate (PADC). We briefly summarize the physical and chemical processes specific to the description of the interaction of ionizing radiation with matter. Then we gather published information in relation to PADC response regarding energy absorption and further transient species formation. Emphasis is given to the chemistry of radicals. Due to a lack of available data in relation with clearly identified unpaired electron carriers in PADC, we use data stemming from surrogate molecules. Based on such data we suggest mechanisms for the decomposition o…

Design of a new high energy rear underrun protective device

2008

In recent years the vehicle design field has followed a progressive evolution by focusing its main interest on passive and active safety levels. One of the most injurious cases for the safety of passengers is the crash between a car and a heavy vehicle (truck). Generally, in fact, when such an occurrence happens, the greatest damage is suffered by the passengers of the car. This is because of the considerable structural difference between the two vehicles and the lack of devices to reduce the injuries of the car passengers. In this work, as a consequence of the previous considerations, we deal with the design of a new protective system for heavy vehicles over 3.5 tons. The new rear underrun…