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11.
Fulvio Tonon 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2010,25(3):245-265
Rabcewicz, 1964, Rabcewicz, 1965 maintained that “tunnels should be driven full face whenever possible”. ADECO, which stands for “Analysis of Controlled Deformations in tunnels”, now allows us to fulfill Rabcewicz’s dream in any stress–strain condition. In order to achieve that dream and its consequent control over cost and schedule, however, NATM must be abandoned for the ADECO. The paper traces the history of the sequential excavation, NATM (as first conceived) and Analysis of Controlled Deformations (ADECO) with the aim of shedding light on the unavoidable use of sequential excavation in “soft ground”, and of highlighting advances in tunnel design and construction that have occurred in Europe after and as alternates to the NATM. The paper presents the basic concepts in the ADECO approach to design, construction and monitoring of tunnels together with some case histories, including: full face excavation for Cassia tunnel (face area > 230 m2) in sands and silts under 5 m cover below an archeological area in Rome, Italy; Tartaguille tunnel (face area > 140 m2) advanced full face in highly swelling and squeezing ground under 100 m cover where NATM led to catastrophic failure, France; and 80 km of tunnels (face area > 140 m2) advanced full face in highly squeezing/swelling ground under 500 m cover for the high-speed railway line between Bologne and Florence, Italy (turnkey contract). 相似文献
12.
Shear behaviour of masonry has been deeply investigated for a lot of masonry types. Nevertheless, there is still a lack of knowledge on the shear response of tuff masonry, which is widely spread in the existing building inventory in seismic areas like as Italy, Turkey, and Japan. To characterize the non-linear behaviour of the unit–mortar interface within tuff masonry, a series of direct shear tests were carried out.In this paper, both experimental results and empirical formulae are presented. Classical shear strength and deformation parameters along with shearing fracture energy and dilatancy were characterized. A shear response surface including both stress–strain diagrams and the frictional strength model is proposed. 相似文献
13.
In the 21st century, all the major countries around the world are coming together to reduce the impact of energy generation and consumption on the global environment. Energy conservation and its efficient usage has become a top agenda on the desks of many governments. In the last decade, the drive to make homes automated and to deliver a better assisted living picked pace and the research into home automation systems accelerated, usually based on a centralized residential gateway. However most devised solutions fail to provide users with information about power consumption of different house appliances. The ability to collect power consumption information can lead us to have a more energy efficient society. The goal addressed in this paper is to enable residential gateways to provide the energy consumption information, in a machine understandable format, to support third party applications and services. To reach this goal, we propose a Semantic Energy Information Publishing Framework. The proposed framework publishes, for different appliances in the house, their power consumption information and other properties, in a machine understandable format. Appliance properties are exposed according to the existing semantic modeling supported by residential gateways, while instantaneous power consumption is modeled through a new modular Energy Profile ontology. 相似文献
14.
This article proposes an analytical model for evaluating the number of simultaneous communications that can be sustained by
an ad-hoc network in which the nodes are equipped with fully adaptive smart antennas. The presented mathematical framework
adopts realistic models for the antenna radiation pattern and the channel behavior, and is able to take into account the network
topology and the characteristics of the medium access control (MAC) protocol in the spatial domain. The model is employed
to investigate the impact of the spatial channel model and of the angular spread on network performance. Additionally, this
article examines the influence of the transmission policy of the control and data packets of the MAC layer on the number of
simultaneous communications. 相似文献
15.
In this work, we propose an index that allows a public authority to order different projects for the construction of onshore wind energy plants and that explicitly takes into account their environmental quality. Wind farm projects are defined as vectors of four attributes: the technical properties of each project, its social impact, its environmental impact, and the share of earnings that proponents offer to the collectivity in compensation for the negative externalities of the wind plant. We define an absolute index that allows the ordering of different proposals and evaluation of the acceptability of each project, providing the monetary value of each point and inducing a truthful revelation of firms' private information. Moreover, we calibrate the index on the basis of data referring to wind plants in Southern Italy and derive the corresponding iso-scoring curves. 相似文献
16.
In the last years Home Automation systems gained new momentum, permeating many human-related environments, from homes to hospitals. The rapid evolution of such systems showed several interoperability pitfalls and a generally insufficient support for advanced user–home interaction. To tackle these emerging issues, recent research works defined the concept of Intelligent Domotic Environments (IDEs) where different automation systems, appliances and devices are integrated into a single powerful environment, capable of providing Ambient Intelligence (AmI) functionalities. IDEs represent one of the first attempts to define a framework for AmI environments based on off-the-shelf domotic systems. This paper contributes to extend IDE capabilities by supporting basic intelligence requirements through a rule-based reasoning mechanism. Starting from a formal model of IDE elements (DogOnt), rules are defined to evaluate environment properties. Property checking is done both off-line, for structural properties, i.e., properties involving the physical structure and configuration of the IDE, and on-line for properties dependent on current IDE states. Two rule languages, SWRL and JenaRules, are considered for rule formalization and their reasoning performance is evaluated by comparing two different rule engines, namely Jess and Jena. Results show that rule-based reasoning can deal with quite complex property checking, effectively addressing basic intelligence for IDEs and providing the basis for more advanced behaviors such as user adaptation and proactive interaction. 相似文献
17.
Fulvio De Santis 《TEST》2007,16(3):504-522
Alternative Bayes factors are families of methods used for hypothesis testing and model selection when sensitivity to priors
is a concern and also when prior information is weak or lacking. This paper deals with two related problems that arise in
the practical use of these model choice criteria: sample size determination and evaluation of discriminatory power. We propose
a pre-experimental approach to cope with both these issues. Specifically, extending the evidential approach of Royall (J Am Stat Assoc 95(451):760–780, 2000) and following De Santis (J Stat Plan Inference 124(1):121–144,
2004), we propose a criterion for sample size choice based on the predictive probability of observing decisive and correct
evidence. The basic idea is to select the minimal sample size that guarantees a sufficiently high pre-experimental probability
that an alternative Bayes factor provides strong evidence in favor of the true hypothesis. It is also argued that a predictive
analysis is a natural approach to the measurement of discriminatory power of alternative Bayes factors. The necessity of measuring
discrimination ability depends on the fact that alternative Bayes factors are, in general, less sensitive to prior specifications
than ordinary Bayes factors and that this gain in robustness corresponds to a reduced discriminative power. Finally, implementation
of the predictive approach with improper priors is discussed and possible strategies are proposed.
相似文献
18.
19.
Urska Vrhovsek Lara Giongo Fulvio Mattivi Roberto Viola 《European Food Research and Technology》2008,226(4):817-824
This study describes the first application of a new procedure for acid hydrolysis of Rubus ellagitannins in methanol, which allows quantification of all the major reaction products (ellagic acid, methyl-sanguisorboate,
methyl gallate and an unknown ellagic acid derivative) and estimation of the mean degree of polymerization (mDP) of Rubus ellagitannins. The ellagitannins of 21 raspberry and 15 blackberry cultivars produced in Trentino, Italy during 2005 were
extracted and characterised. The total content of ellagitannins was shown to vary by a factor of 2 among raspberry cultivars
and by a factor of 4 among blackberry cultivars. 相似文献
20.
Fulvio Corradini Giancarlo Franchini Andrea Marchetti Mara Tagliazucchi Lorenzo Tassi 《加拿大化工杂志》1997,75(3):494-501
The kinematic viscosities (v) were measured for nine binary solvent mixtures of 2-methoxyethanol (ME) + 1,2-dimethoxyethane (DME) at nineteen temperatures ranging from ?10 to +80°C. The experimental data have been used to test some empirical equations of the type v = v(T), v = v(X1) and v = v(T, X1). The viscosities of all the mixtures increase from the values of pure DME to that of ME as the mole fraction of ME increases, and always yield a negative excess property (vE) at all the investigated temperatures. Furthermore, thermodynamic parameters of viscous flow have been evaluated on the basis of the Eyring theory. The excess free energy of activation of viscous flow (ΔGE) vs X2 plot suggests the presence of a stable hetero-adduct, having ME : DME = 1 : 1 stoichiometric ratio. 相似文献