Search results for "reliability"
showing 10 items of 1563 documents
Primitive rispetto all’ oscillazione
2002
We study the real valued functions having a primitive with respect to the oscillation or a primitive with respect to the oscillation up to anegligible set.
Integrated production of biopolymers with industrial wastewater treatment: Effects of OLR on process yields, biopolymers characteristics and mixed mi…
2022
The production of polyhydroxyalkanoates (PHA) using industrial wastewaters as feedstocks is a current and challenging topic. This study investigated the production of biopolymers by a mixed microbial culture under different OLRs equal to 1 kgCOD m-3d-1 (Period 1), 2 kgCOD m-3d-1 (Period 2) and 3 kgCOD m-3d-1 (Period 3). The maximum PHA content was achieved in Period 2 (0.38 gPHA gTSS-1), whereas lower values were obtained in Period 1 (0.13 gPHA gTSS-1) and Period 3 (0.26 gPHA gTSS-1). Overall, the maximum PHA productivity resulted equal to 0.08 gPHA L-1h-1 (P2), 0.05 gPHA L-1h-1 (P1) and 0.04 gPHA L-1h-1 (P3), respectively. The molecular weight of the PHA increased from Period 1 (250 kDa) t…
Evaluation of motorway reliability based on the identification of spot speed stochastic processes. The case of A22 motorway, Italy
2012
The evaluation of motorway reliability is a subject of great interest for researchers of traffic engineering. For easy recognizable reasons, this subject is very important in theoretical studies and for applications, e.g. evaluation of capacity and traffic control on motorway. In this paper the different conceptions of reliability in technical and scientific literature are compared with the following definition: reliability of traffic stream, for a time interval T, is “the conditioned probability that level of speed spot process does not decrease during T as far as the section in which limit density is reached, given that the level at instant zero is equal to the average speed corresponding…
Life cycle environmental assessment of retaining walls in unsaturated soils
2022
Abstract Retaining structures above groundwater level support soils that are usually in a state of partial saturation and subject to the actions of atmospheric agents. The current design approach considers the possible extremes of soil conditions – either totally dry or totally saturated – but it neglects matric suction’s contribution to soil shear strength. This work aims to describe how unsaturated-soil mechanics of can positively influence the sustainability of retaining structures through a holistic, multidisciplinary, geotechnical, and environmental analysis. The geotechnical analysis allows to estimate the lateral earth pressure of a geostructure in both unsaturated and extreme soil c…
Prediction of concrete materials compressive strength using surrogate models
2022
Using soft computing methods could be of great interest in predicting the compressive strength of Ultra-High-Performance Fibre Reinforced Concrete (UHPFRC). Therefore, this study developed four soft computing techniques. The models are the Linear- relationship (LR), pure quadratic, M5P-tree (M5P), and artificial neural network (ANN). The models were trained and developed using 306 datasets comprising 11 input parameters, including the curing temperature (T), the water-to-cement ratio (w/c), silica fume (SF), cement content (C), fiber content (Fb), water (W), sand content (S), superplasticizer (SP), fiber aspect ratio (AR) and curing time (t). Experimental results were used and compared to t…
Hardening structures isolated by double sliding devices: Seismic reliability-based design approach
2019
This study deals with seismic reliability-based design (SRBD) relationships in terms of behavior factors and displacement demands for hardening structures equipped with double friction pendu-lum system (DFPS) bearings. An equivalent 3dof system having a hardening post-yield slope is adopted to describe the superstructure behavior, whereas velocity-dependent laws are assumed to model the responses of the two surfaces of the DFPS. The yielding characteristics of the super-structures are defined for increasing behavior factors in compliance with the seismic hazard of L’Aquila site (Italy) and with NTC18 assuming a lifetime of 50 years. Considering several natural seismic records and building p…
Development of a software package with GUI for the evaluation of monolithicity factors of RC jacketed columns
2023
The design of reinforced concrete (RC) jacketing for retrofitting substandard columns is a common practice when approaching the structural rehabilitation design of existing structures. In this framework, international technical codes suggest to assume the hypothesis of monolithic section and finally affecting the deduced performances by some empirical factors, known in the literature as monolithicity factors. The assessment of these coefficients is a difficult task, and only some rough assumptions can be found in the modern codes. This paper presents the development of a software package able to perform the static non-linear analysis of RC jacketed columns and evaluating the actual value of…
Effect of the different data survey scale on assessment of seismic exposure and vulnerability of the historic center of Caltabellotta
2019
The results of the prediction of exposure and seismic vulnerability for the buildings of the historic center of Caltabellotta, obtained with databases of different levels of accuracy, are compared. In particular, the results obtained on the basis of the estimation of the characteristics and of the distribution of the typologies derived from the filling in of the CARTIS sheets on a sector scale are compared with those obtained through a survey from the outside to a building scale. In this latter area, indicators contained in the CARTIS are suitably supplemented with those available in the literature, partly modified to adapt them to the local reality. The vulnerability is evaluated on the ba…
Experimental evaluation of the reliability of the adhesive joint in a 3rd-generation-solar-cell-integrated glass block
2017
Glass block is a building product that has been widely used since the mid-1800s for the construction of natural light capturing technical elements and, in the last decades, of translucent building envelopes. In a framework of increased quality requirements in terms of energy saving and environmental sustainability, innovations have been introduced to its standard configuration, including the integration of 3rd generation solar cells within the glass block, in order to improve its performance and make it capable of producing clean energy. Indeed, one of the two constituting glass shells has been integrated with a pre-assembled photovoltaic module and then bonded to a plastic “thermal belt” a…
A Quantum-Inspired Classifier for Early Web Bot Detection
2022
This paper introduces a novel approach, inspired by the principles of Quantum Computing, to address web bot detection in terms of real-time classification of an incoming data stream of HTTP request headers, in order to ensure the shortest decision time with the highest accuracy. The proposed approach exploits the analogy between the intrinsic correlation of two or more particles and the dependence of each HTTP request on the preceding ones. Starting from the a-posteriori probability of each request to belong to a particular class, it is possible to assign a Qubit state representing a combination of the aforementioned probabilities for all available observations of the time series. By levera…