Search results for "CONSTRUCTION"

Drivers of peat accumulation rate in a raised bog: impact of drainage, climate, and local vegetation composition

2017

We used variation partitioning to assess the relative importance of drainage, climate and local vegetation composition for the development of a raised bog. As a case study we selected Teici (Teici) Bog in Latvia (north-east Europe). Explanatory variables together explained 74 % of the variation in peat accumulation and only the residue of 26 % remained unexplained. Our study showed that the local vegetation composition and dominant Sphagnum species significantly influence peat accumulation rates. The results of linear models revealed that, under natural conditions, minor drainage and even strong drainage of the peat is associated with a positive growth balance of the system. However, draina…

Data Compression Approach for Long-Term Monitoring of Pavement Structures

2019

Pavement structures are designed to withstand continuous damage during their design life. Damage starts as soon as the pavement is open to traffic and increases with time. If maintenance activities are not considered in the initial design or considered but not applied during the service life, damage will grow to a point where rehabilitation may be the only and most expensive option left. In order to monitor the evolution of damage and its severity in pavement structures, a novel data compression approach based on cumulative measurements from a piezoelectric sensor is presented in this paper. Specifically, the piezoelectric sensor uses a thin film of polyvinylidene fluoride to sense the ener…

Pollutant Emissions in Ports: A Comprehensive Review

2021

In recent decades, maritime transport demand has increased along with world population and global trades. This is associated with higher pollution levels, including the emissions of GHG and other polluting gases. Ports are important elements within maritime transport and contribute themselves to pollutant emissions. This paper aims to offer a comprehensive yet technical review of the latest related technologies, explaining and covering aspects that link ports with emissions, i.e., analyzing, monitoring, assessing, and mitigating emissions in ports. This has been achieved through a robust scientific analysis of very recent and significant research studies, to offer an up-to-date and reliable…

NANOTECHNOLOGY IN CONSTRUCTION

2011

An Information Systems Design Product Theory for Software Project Estimation and Measurement Systems

2009

There is relatively little research on software Project Estimation and Measurement Systems (PEMS). Commercial PEMS vary in functionality and effective- ness. Their intended users thus do not know what to ex- pect from PEMS and how to evaluate them. This paper creates an information system design product theory for the class of PEMS that prescribes the meta-requirements, the meta-design, and applicable theories for all products within the class. Meta-requirements and the meta-design are derived from the project estimation and measurement literature, experiences obtained during more than ten years of empirical work in Finnish Software Measurement Association, and a commercially available PEMS.

Relationships among Bicycle Rider Behaviours, Anger, Aggression, and Crashes in Finland

2022

Riding a bicycle is increasingly encouraged as a sustainable transport solution, especially in urban areas. However, safety concerns, both perceived and actual, can significantly lower the willingness to ride among the population. To support cycling planning and policy in the double task of increasing the levels of cycling while mitigating crash risk, there is a need to better understand the behaviours and attitudes of bicycle riders. In this manuscript, we study a cohort of Finnish bicycle riders through four questionnaires, the Cycling Behaviour Questionnaire (CBQ), Cyclist Risk Perception and Regulation Scale (RPRS), Cyclist Anger Scale (CAS), and Cyclist Aggression Expression Inventory …

Concrete arch bridges built by lattice cantilevers

2013

In this paper a study about concrete arch bridges built by lattice cantilevers is presented. Lattice cantilevers are partial structures composed of deck, arch, piers and provisional steel diagonals, organized as reticular cantilever girders, in order to build arch bridges without the use of centrings, supports or temporary towers. Characteristics of this construction methodology with its variants are explained together with their implications in the erection sequence. Partial elastic scheme method is implemented in order to find initial forces of temporary cables and a forward analysis is carried out to follow the actual sequence of construction, by extending a procedure already applied to …

Tecniche costruttive antisismiche in Calabria tra la fine dell'Ottocento e l'inizio del Novecento,

2016

La presente memoria intende indagare lo sviluppo delle costruzioni antisismiche in Calabria in un periodo compreso tra gli anni Ottanta dell'Ottocento e i primi anni del Novecento. Lo studio è incentrato sulle tecniche costruttive adottate nelle ricostruzioni post-terremoto realizzate in un periodo immediatamente antecedente il sisma che colpì Messina e Reggio Calabria nel 1908, dopo il quale si registra un progressiva affermazione della tecnologia del cemento armato. In questo arco cronologico si assiste a un notevole sviluppo degli studi nel campo della costruzione antisismica, con una prevalente riproposizione di sistemi costruttivi tradizionali e con le prime sperimentazioni sul cemento…

Experimental study of Si–Al substitution in calcium-silicate-hydrate (C-S-H) prepared under equilibrium conditions.

2009

International audience; C-A-S-H of varying Al/Si and Ca/(Al+Si) ratios have been prepared introducing C-S-H (Ca/Si=0.66 and 0.95) at different weight concentrations in a solution coming from the hydration of tricalcium aluminate (Ca3Al2O6) in water. XRD and EDX (TEM) analyses show that using this typical synthesise procedure, pure C-A-S-H is obtained only for calcium hydroxide concentrations below 4.5 mmol L−1. Otherwise, calcium carboaluminate or strätlingite is also present beside C-A-S-H. The tobermorite-like structure is maintained for C-A-S-H. A kinetic study has shown that the formation of C-A-S-H is a fast reaction, typically less than a few hours. The Ca/(Al+Si) ratio of C-A-S-H mat…

FPGA implementation of a deep learning algorithm for real-time signal reconstruction in particle detectors under high pile-up conditions

2019

The analog signals generated in the read-out electronics of particle detectors are shaped prior to the digitization in order to improve the signal to noise ratio (SNR). The real amplitude of the analog signal is then obtained using digital filters, which provides information about the energy deposited in the detector. The classical digital filters have a good performance in ideal situations with Gaussian electronic noise and no pulse shape distortion. However, high-energy particle colliders, such as the Large Hadron Collider (LHC) at CERN, can produce multiple simultaneous events, which produce signal pileup. The performance of classical digital filters deteriorates in these conditions sinc…