A new test cell for the evaluation of thermo-physical performance of facades building components

How do the new building façade components work under real climatic conditions? The question is especially related to the dynamic behaviour of new and complex components such as the ventilated walls, the Phase Change Material, or others that use nano-technologies and aerogels. One of the objectives of the undergoing research activity, named Abitare Mediterraneo, is the evaluation of their thermal behaviour through the use of an outdoor test cell, in order to reproduce under the real external conditions the performance of these components, and consequently define the main thermal parameters such as the attenuation factor and the thermal inertia, characterising the component; moreover, the results will be used to write new algorithms for dynamic simulation tools allowing an appropriate evaluation of the complex behaviour of the whole building at a real scale condition. The new test cell is realised in Florence, Italy. The design starts from the study of the experience of the existing PASSYS test cells, overtaking the main weakness of the building structure and of the heat-flux sensors.     

Optical and electrical characterization of carbon nanoparticles produced in laminar premixed flames

Optical and electrical properties of carbonaceous particles produced in laboratory scale, premixed ethylene/air flames are obtained. Light absorption and Raman spectroscopy show that the change in particle nanostructure follows a graphitization trajectory as the flame richness increases. The optical band gap decreases and the size of the aromatic network in the particle increases, while the interlayer spacing between parallel layers decreases. The electrical conductivity of the materials increases by increasing flame richness in agreement to the graphitization trajectory. A non-ohmic behavior has been found and explained in terms of electron tunneling in a percolative network. Our results show that the electrical properties of flame formed carbon nanoparticles are strongly dependent on their nanostructure, and hence they have to be used carefully for the determination of particle concentration with conductometric sensors. Moreover, the dependence of the electrical properties of combustion formed particles might be useful for the development of cheap sensors for the selective detection of different classes of combustion aerosols.     

Cycle time-oriented mid-term production planning for semiconductor wafer fabrication

Wafers are produced in an environment with uncertain demand and failure-prone machines. Production planners have to react to changes of both machine availability and target output, and revise plans appropriately. The scientific community mostly proposes WIP-oriented mid-term production planning to solve this problem. In such approaches, production is planned by defining targets for throughput rates and buffer levels of selected operations. In industrial practice, however, cycle time-oriented planning is often preferred over WIP-oriented planning. We therefore propose a new linear programming formulation, which facilitates cycle time-oriented mid-term production planning in wafer fabrication. This approach plans production by defining release quantities and target cycle times up to selected operations. It allows a seamless integration with the subordinate scheduling level. Here, least slack first scheduling translates target cycle times into lot priorities. We evaluate our new methodology in a comprehensive simulation study. The results suggest that cycle time-oriented mid-term production planning can both increase service level and reduce cycle time compared to WIP-oriented planning. Further, it requires less modelling effort and generates plans, which are easier to comprehend by human planners.     

OPTIMIZED PROCEDURE TO EVALUATE THE THERMAL ENERGY TRANSFER IN HEMODIALYSIS TREATMENT

Hemodialysis treatment is biased by complications during its operative phases. One of these potential accidents consists in intradialytic hypotension, that causes discomfort to the patient and may even increase the risk of death. Therefore, it is very important to predict these events in routine clinical procedures. A cause of hypotension may be thermal energy/heat exchanges between extracorporeal system and the surrounding environment. A model to evaluate these heat losses is proposed and improved in order to maintain constant patient blood temperature. A convenient procedure is defined to improve and optimize clinical treatment. Although most hemodialysis machines automatically control the dialysate solution temperature starting from peripheral body temperature measurements, the proposed method is based on the control of the pre-dialysis core temperature of the patient, and the temperature of the blood entering the artery from the extracorporeal circuit after the treatment in the dialyzer. Measurements of arterial and venous blood temperatures are obtained in a non invasive way by a suitable estimate of the thermal energy exchanges between the blood and the environment during the extracorporeal recirculation. The suggested model guarantees a constant core temperature of the patient, improving prevention from intradialytic hypotension.     

High-speed single cable synchronization system for data-converters

A clock-cycle accurate synchronization technique for fully integrated data-converters is presented. Only a single cable is needed to distribute both the required synchronization signal and the converter clock. Different possible implementations, both to generate and decompose the distributed signal, are presented. A discrete component generator circuit is discussed. To avoid setup and hold time violations, on-chip signal reconstruction is unavoidable. A 40 nm CMOS recovery circuit was developed. Simulation results, including layout parasitics, show the wide frequency operating range of the proposed technique.     

Social Exclusion in Later Life: A Systematic Review of the Literature

In the last decade, there has been a growing awareness regarding social exclusion. Considering the ageing population and the likelihood of older people being socially excluded, the aims of this article are to: (1) review existing studies concerning social exclusion in later life; and (2) identify how environmental and life-course perspectives are presented in studies focusing on social exclusion in later life. A systematic review in seven scientific databases was conducted to explore the peer-reviewed evidence. In total, 26 articles were included and analysed. Findings describe the variety of methods, conceptualisation, dimensions and measures used in this recent area of research. Determinants of social exclusion in later life are discussed and life-course and environmental perspectives are examined. The discussion highlights the complex character of the concept and measurement of social exclusion, and the presence of general and age-specific dimensions of social exclusion in later life. The time and context relativity and the need for life-course and environmental perspectives on social exclusion in later life are discussed. Finally, future directions of research are discussed.     

Cycling reliability of RF-MEMS switches with Gold–Platinum multilayers as contact material

Microsystem Technologies - Contact resistance is the main parameter used for assessing the high cycling reliability of RF microelectromechanical (RF-MEMS) switches. In this paper the use of a...     

A New Stable Splitting for the Isentropic Euler Equations

In this work, we propose a new way of splitting the flux function of the isentropic compressible Euler equations at low Mach number into stiff and non-stiff parts. Following the IMEX methodology, the latter ones are treated explicitly, while the first ones are treated implicitly. The splitting is based on the incompressible limit solution, which we call reference solution. An analysis concerning the asymptotic consistency and numerical results demonstrate the advantages of this splitting.     

Controlled-NOT gate sequences for mixed spin qubit architectures in a noisy environment

Explicit controlled-NOT gate sequences between two qubits of different types are presented in view of applications for large-scale quantum computation. Here, the building blocks for such composite systems are qubits based on the electrostatically confined electronic spin in semiconductor quantum dots. For each system the effective Hamiltonian models expressed by only exchange interactions between pair of electrons are exploited in two different geometrical configurations. A numerical genetic algorithm that takes into account the realistic physical parameters involved is adopted. Gate operations are addressed by modulating the tunneling barriers and the energy offsets between different couple of quantum dots. Gate infidelities are calculated considering limitations due to unideal control of gate sequence pulses, hyperfine interaction and charge noise.