Search results for "LOAD"

Fifty Years of PMV Model: Reliability, Implementation and Design of Software for Its Calculation

2019

In most countries, PMV is the reference index for the assessment of thermal comfort conditions in mechanically conditioned environments. It is also the basis to settle input values of the operative temperature for heating and cooling load calculations, sizing of equipment, and energy calculations according to EN 16798-1 and 16798-2 Standards. Over the years, great effort has been spent to study the reliability of PMV, whereas few investigations were addressed to its calculation. To study this issue, the most significant apps devoted to its calculation have been compared with a reference software compliant with EN ISO 7730 and the well-known ASHRAE Thermal Comfort Tool. It has been revealed …

Understanding the influence of lewis acids in the regioselectivity of the diels-alder reactions of 2-methoxy-5-methyl-1,4-benzoquinone: a dft study

2009

The mechanisms of the Diels–Alder (DA) reactions of 2-methoxy-5-methyl-1,4-benzoquinone 1 with 2-methyl-1,3-butadiene 2, in the absence and in the presence of LA catalysts, have been studied using the DFT method at the B3LYP/6-31G(d) level of theory. The uncatalyzed DA reactions between 1 and 2 take place via synchronous concerted TSs. The large activation barrier as well as the low stereo and regioselectivity associated with the uncatalyzed process are in clear agreement with the non-polar character of the cycloaddition. Coordination of the LA catalysts, BF3 or SnCl4, to the oxygen atoms of the benzoquinone 1 produces a large acceleration of the reaction, which can be associated with the l…

BIAXIAL CURVATURE AND DUCTILITY CAPACITY OF RC COLUMN BASE CROSS SECTIONS

2014

The deformation performance of the base cross sections of reinforced concrete buildings is fundamental when large seismic events occur allowing the structure to have large excursions in nonlinear field and guaranteeing an overall ductile behaviour. It is well known that the axial force acting on columns significantly reduces the curvature capacity of the sections and for this reason the technical codes give design criteria stating a limitation in order to preserve the displacement capacity. It is also recognized that when biaxial bending occur the cross section undergo a loss in strength capacity. Starting the study of from Bresler (1960), which provided suitable expression to predict 3D li…

Cloud Infrastructure for Skin Cancer Scalable Detection System

2018

Skin cancer diagnostics is one of the medical areas where early diagnostic allows achieving patients’ high survival rate. Typically, skin cancer diagnostic is performed by dermatologist, since the amount of such specialists is limited, mortality rate is high [1]. By creating the low cost and easy to use diagnostic device, it is possible to bring skin cancer diagnostic to primary care physicians and allow to check much more persons and diagnose skin cancer on the early stages. There are several existing devices, that provide skin cancer diagnostics [2]. Most of them process the skin images locally and have limited diagnostic capabilities; some of them send images to dermatologists for manual…

Extensible Wind Tower

2014

The diffusion of wind energy generators is restricted by their strong landscape impact. The PERIMA project is about the development of an extensible wind tower able to support a wind machine for several hundred kW at its optimal working height, up to more than 50 m. The wind tower has a telescopic structure, made by several tubes located inside each other with their axis in vertical direction. The lifting force is given by a jack-up system confined inside a shaft, drilled below the ground level. In the retracted tower configuration, at rest, tower tubes are hidden in the foundation of the telescopic structure, located below the ground surface, and the wind machine is the only emerging part …

Combined IT and power supply infrastructure sizing for standalone green data centers

2021

International audience; In this work, we propose a two-step methodology for designing and sizing a data center solely powered by local renewable energy. The first step consists in determining the necessary IT equipment for processing a given IT workload composed of batch and service tasks. We propose an adapted binary search algorithm and prove its optimality to find the minimum number of servers to handle the IT workload. When the IT sizing is computed, the second step consists in defining the supplying electrical infrastructure using wind turbines and photovoltaic panels as primary sources. Batteries and a hydrogen system are added as secondary sources for short- and long-term energy stor…

Grid interaction and environmental impact of a net zero energy building

2020

Abstract The concept of Net Zero Energy Building (NZEB), as a grid-connected building that generates as much energy as it uses over a given period, has been developing through policies and research agendas during the last decade as a contribution towards the decarbonization of the building sector. However, since the most applicable and widely used renewable energy supply options are non-programmable, the large-scale NZEBs diffusion into the existing power grids can seriously affect their stability having a relapse on operation costs and environmental impacts. In this context, the study aims at performing the design of the energy systems to be used in the case-study through a wide numbers of…

Towards an integrated design of renewable electricity generation and storage systems for NZEB use: A parametric analysis

2021

Abstract Although nearly zero energy buildings have attracted growing research attention, literature analysis shows that only a limited number of researches try to couple load match/grid interaction issues and environmental impacts in early design stages. The study proposes a novel multidisciplinary design approach that allows to integrate these two conflicting aspects aiming to find trade-offs. The proposed approach has been applied to a building case study, equipped with a photovoltaics system without energy storage. The results show that even though on yearly basis the energy use (5,290 kWhe) is largely overcome by the on-site energy generation (8069 kWhe), an oversized PV system alone m…

A review of the use of information and communication technologies for dietary assessment.

2009

Presently used dietary-assessment methods often present difficulties for researchers and respondents, and misreporting errors are common. Methods using information and communication technologies (ICT) may improve quality and accuracy. The present paper presents a systematic literature review describing studies applying ICT to dietary assessment. Eligible papers published between January 1995 and February 2008 were classified into four assessment categories: computerised assessment; personal digital assistants (PDA); digital photography; smart cards. Computerised assessments comprise frequency questionnaires, 24 h recalls (24HR) and diet history assessments. Self-administered computerised as…

2021

An observational cross-sectional survey was planned to analyze the weekly workload reduction of German dentists during lockdown due to the global COVID-19 pandemic. Participants were predominantly members of the Free Association of German Dentists and filled in an online questionnaire. The questionnaire was sent to a total of 9416 dentists, with a response rate of 27.98% (n = 2635). Respondents were divided into seven macro areas by gross domestic product. Nearly two-thirds of dentists (65.16%) reported a reduction in their practice workload of more than 50% compared to the pre-pandemic period with statistically significant differences between German macro areas (p < 0.01). Weekly worklo…