An existence result for the fractional Kelvin–Voigt’s model on time-dependent cracked domains

We prove an existence result for the fractional Kelvin–Voigt’s model involving Caputo’s derivative on time-dependent cracked domains. We first show the existence of a solution to a regularized version of this problem. Then, we use a compactness argument to derive that the fractional Kelvin–Voigt’s model admits a solution which satisfies an energy-dissipation inequality. Finally, we prove that when the crack is not moving, the solution is unique

Intelligent conditional collaborative private data sharing

With the advent of distributed systems, secure and privacy-preserving data sharing between different entities (individuals or organizations) becomes a challenging issue. There are several real-world scenarios in which different entities are willing to share their private data only under certain circumstances, such as sharing the system logs when there is indications of cyber attack in order to provide cyber threat intelligence. Therefore, over the past few years, several researchers proposed solutions for collaborative data sharing, mostly based on existing cryptographic algorithms. However, the existing approaches are not appropriate for conditional data sharing, i.e., sharing the data if and only if a pre-defined condition is satisfied due to the occurrence of an event. Moreover, in case the existing solutions are used in conditional data sharing scenarios, the shared secret will be revealed to all parties and re-keying process is necessary. In this work, in order to address the aforementioned challenges, we propose, a “conditional collaborative private data sharing” protocol based on Identity-Based Encryption and Threshold Secret Sharing schemes. In our proposed approach, the condition based on which the encrypted data will be revealed to the collaborating parties (or a central entity) could be of two types: (i) threshold, or (ii) pre-defined policy. Supported by thorough analytical and experimental analysis, we show the effectiveness and performance of our proposal

Ergodicity breaking in strong and network-forming glassy system

The temperature dependence of the non-ergodicity factor of vitreous GeO$_2$, $f_{q}(T)$, as deduced from elastic and quasi-elastic neutron scattering experiments, is analyzed. The data are collected in a wide range of temperatures from the glassy phase, up to the glass transition temperature, and well above into the undercooled liquid state. Notwithstanding the investigated system is classified as prototype of strong glass, it is found that the temperature- and the $q$-behavior of $f_{q}(T)$ follow some of the predictions of Mode Coupling Theory. The experimental data support the hypothesis of the existence of an ergodic to non-ergodic transition occurring also in network forming glassy systems

Ignition and Flashover of Reduced Scale Compartments with Timber Ceilings

Experiments on reduced-scale compartments with timber ceilings and floors were conducted to investigate the ignition of the ceiling and growth to flashover. Pool fires of various sizes were ignited and measurements were made of temperature in the plume and ceiling jet, and mass of the timber ceiling and floor. The compartment geometry was also systematically varied. The results showed that ignition of the ceiling occurred when the measured temperature at ceiling level was between 328°C and 347°C. This aligned with intermittent flame impingement on the ceiling from the initiating fire. Following ignition of the ceiling, in most cases the fire subsequently spread across the ceiling resulting, ultimately, in ignition of the floor. It was found that duration of preheating of the ceiling (by the ceiling jet) strongly influenced flame spread. In some cases, ignition occurred, but did not result in continuous flame spread across the ceiling – in these cases it was found that the ceiling jet was cooler due to wider geometry of the compartment. The data were compared against existing correlations from the literature, and it was found that existing methods may be used to predict whether ignition of the ceiling may occur and the conditions for flashover

Free light chain UV quantification compared with immunochemical measurement: How dimers and monomers may influence the results

Serum κ and λ free light chain (FLC) levels are important for the management of plasma cell disorders. Immunochemical measurements on automated platforms with different reagents occasionally return different results that make them not interchangeable. The reasons for this behaviour are not clear and it is not known which result is the most accurate. The aim of the study is to quantify naturally occurring FLCs with a reference method (UV absorbance) in a sample devoid of other sources of UV absorbance. This was possible on a particular urine sample containing only lambda FLC proteins, dialyzed to clear it from low molecular weight UV absorbing compounds. The sample was submitted to Fast Protein Liquid Chromatography separation with a size-exclusion column in order to separate the FLC monomers and dimers. FLCs were also measured with the Freelite and N Latex FLC methods and the results were compared. The results demonstrated that the amount of FLC calculated on the basis of UV absorbance was overestimated by both immunochemical methods, and that the amount measured by the two reagents was affected by the different proportions of dimers or monomers. The present findings may be useful for the comprehension of the immunochemical measurement of FLC

Spectral- and size-resolved mass absorption efficiency of mineral dust aerosols in the shortwave spectrum: a simulation chamber study

This paper presents new laboratory measurements of the mass absorption efficiency (MAE) between 375 and 850 nm for 12 individual samples of mineral dust from different source areas worldwide and in two size classes: PM10:6 (mass fraction of particles of aerodynamic diameter lower than 10.6 \u3bcm) and PM2:5 (mass fraction of particles of aerodynamic diameter lower than 2.5 \u3bcm). The experiments were performed in the CESAM simulation chamber using mineral dust generated from natural parent soils and included optical and gravimetric analyses. The results show that the MAE values are lower for the PM10:6 mass fraction (range 37\u2013135x10-3 m2 g-1 at 375 nm) than for the PM2:5 (range 95\u2013711x10-3 m2 g-1 at 375 nm) and decrease with increasing wavelength as lambda-AAE, where the \uc5ngstr\uf6m absorption exponent (AAE) averages between 3.3 and 3.5, regardless of size. The size independence of AAE suggests that, for a given size distribution, the oxide fraction, which could ease the application and the validation of climate models that now start to include the representation of the dust composition, as well as for remote sensing of dust absorption in the UV\u2013vis spectral region