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61.
Michele?RisiEmail author Giuseppe?Scanniello Genoveffa?Tortora 《Formal Aspects of Computing》2012,24(3):307-330
In this paper we present an approach to automate the architecture recovery process of software systems. The approach is built
on information retrieval and clustering techniques, and, in particular, uses Latent Semantic Indexing (LSI) to get similarities
among software entities (e.g., programs or classes) and the k-means clustering algorithm to form groups of software entities
that implement similar functionality. In order to improve computational time in the context of the software evolution and
then reduce energy waste, the architecture recovery process can be also applied by using fold-in and fold-out mechanisms that,
respectively, add and remove software entities to the LSI representation of the understudy software system. The approach has
been implemented in a prototype of a supporting software system as an Eclipse plug-in. Finally, to assess the approach and
the plug-in, we have conducted an empirical investigation on five open source software systems implemented using the programming
languages Java and C/C++. In the investigation special emphasis has been also given to the effect of using the fold-in and
fold-out mechanisms. 相似文献
62.
Reinhard Miller Dmitri Grigoriev Jürgen Krägel Alexander V. Makievski Valentin B. Fainerman Volodymyr I. Kovalchuk Libero Liggieri Francesca Ravera Michele Ferrari Eva Santini Giuseppe Loglio Victoria Dutschk Thodoris Karapantsios 《Microgravity science and technology》2006,18(3-4):104-107
The utilisation of particle-surfactants nanostructures as stabilising agents represents today the technologic and scientific frontier in the stabilisation of liquid films in emulsion and foams. This topic will be addressed by the proposal STEFAN (STabilisation of Emulsions and FoAms by Nanoparticles), proposed by European groups in the framework of the ESA AO-2004 for Life and Physical Sciences and Applied Research projects Similarly to what can be observed for surfactant-stabilised emulsions and foams, microgravity provides ideal conditions for the investigation of the hierarchy of involved objects: interfacial layer, liquid film, dispersed systems foam or emulsion. Microgravity experiments are planned by refurbishing the Experimental Container FASES for the ISS Fluid Science Laboratory and the facility FASTER for the European Drawer Rack, already under development in existing research programmes. Here the scientific guidelines of the project are presented together with examples and preliminary results on the effect of nano-particle-surfactant structures adsorbed at liquid interfaces. First experimental results have been achieved for particle monolayers at the water/air interface and a thermodynamic model was derived to describe the obtained surface pressure-area isotherms. 相似文献
63.
Germani A. Manes C. Palumbo P. 《IEEE transactions on circuits and systems. I, Regular papers》2006,53(6):1266-1277
This paper considers the problem of state estimation for discrete-time systems whose dynamics randomly switches between two linear stochastic behaviors (bimodal systems). The novelty of this paper is that no statistical information on the switching process is assumed available for the filter design. Two different approaches are here proposed to solve the estimation problem in these conditions. One method is based on a combined use of stochastic singular systems and of the minimax filtering theory, while the other relies on the maximum entropy principle. Based on these approaches two filtering algorithms are derived, whose features are theoretically and numerically compared. Some attention has been devoted to the study of the asymptotic properties of both the filters. 相似文献
64.
The effects of serotonergic agonists were examined in intact and spinal fetuses, using an in vivo fetal rat preparation. On Gestational Day 20, fetuses were prepared with a midthoracic or sham spinal transection. Dose-response curves were obtained for quipazine (nonselective 5-hydroxytryptamine [5-HT] agonist; 1.0-10.0 mg/kg), CGS-12066A (5-HT1B agonist; 1.0-30.0 mg/kg), and α-methylserotonin (α-Me-5-HT; 5-HT? agonist; 0.2-15.0 mg/kg). During a 10-min test, each of the agonists (delivered via intraperitoneal injection) influenced fetal behavior: They increased the occurrence of head movements, mouthing, and hindlimb stepping. Quipazine and α-Me-5-HT also promoted hindlimb activity in spinal fetuses. Thus, stimulation of the fetal 5-HT system modulates motor activity at multiple levels of the developing central nervous system. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
65.
J-integral has been calculated along the free-of-stress border of deep and shallow rounded notches under torsion, under the hypothesis of a linear elastic behaviour of the material. Two exact closed-form solutions have been obtained which make it explicit the influence of the notch opening angle and the notch root radius. When the notch root radius tends to zero the proposed solution matches the expression for the corresponding pointed V-notch case. 相似文献
66.
Maria Teresa Vietri Giovanna DElia Gemma Caliendo Marianna Resse Amelia Casamassimi Luana Passariello Luisa Albanese Michele Cioffi Anna Maria Molinari 《International journal of molecular sciences》2021,22(7)
Prostate cancer (PCa) is globally the second most diagnosed cancer type and the most common cause of cancer-related deaths in men. Family history of PCa, hereditary breast and ovarian cancer (HBOC) and Lynch syndromes (LS), are among the most important risk factors compared to age, race, ethnicity and environmental factors for PCa development. Hereditary prostate cancer (HPCa) has the highest heritability of any major cancer in men. The proportion of PCa attributable to hereditary factors has been estimated in the range of 5–15%. To date, the genes more consistently associated to HPCa susceptibility include mismatch repair (MMR) genes (MLH1, MSH2, MSH6, and PMS2) and homologous recombination genes (BRCA1/2, ATM, PALB2, CHEK2). Additional genes are also recommended to be integrated into specific research, including HOXB13, BRP1 and NSB1. Importantly, BRCA1/BRCA2 and ATM mutated patients potentially benefit from Poly (ADP-ribose) polymerase PARP inhibitors, through a mechanism of synthetic lethality, causing selective tumor cell cytotoxicity in cell lines. Moreover, the detection of germline alterations in MMR genes has therapeutic implications, as it may help to predict immunotherapy benefits. Here, we discuss the current knowledge of the genetic basis for inherited predisposition to PCa, the potential target therapy, and the role of active surveillance as a management strategy for patients with low-risk PCa. Finally, the current PCa guideline recommendations are reviewed. 相似文献
67.
The Impact of Nonalcoholic Fatty Liver Disease on Renal Function in Children with Overweight/Obesity
Lucia Pacifico Enea Bonci Gian Marco Andreoli Michele Di Martino Alessia Gallozzi Ester De Luca Claudio Chiesa 《International journal of molecular sciences》2016,17(8)
The association between nonalcoholic fatty liver disease (NAFLD) and chronic kidney disease has attracted interest and attention over recent years. However, no data are available in children. We determined whether children with NAFLD show signs of renal functional alterations, as determined by estimated glomerular filtration rate (eGFR) and urinary albumin excretion. We studied 596 children with overweight/obesity, 268 with NAFLD (hepatic fat fraction ≥5% on magnetic resonance imaging) and 328 without NAFLD, and 130 healthy normal-weight controls. Decreased GFR was defined as eGFR < 90 mL/min/1.73 m2. Abnormal albuminuria was defined as urinary excretion of ≥30 mg/24 h of albumin. A greater prevalence of eGFR < 90 mL/min/1.73 m2 was observed in patients with NAFLD compared to those without liver involvement and healthy subjects (17.5% vs. 6.7% vs. 0.77%; p < 0.0001). The proportion of children with abnormal albuminuria was also higher in the NAFLD group compared to those without NAFLD, and controls (9.3% vs. 4.0% vs. 0; p < 0.0001). Multivariate logistic regression analysis revealed that NAFLD was associated with decreased eGFR and/or microalbuminuria (odds ratio, 2.54 (confidence interval, 1.16–5.57); p < 0.05) independently of anthropometric and clinical variables. Children with NAFLD are at risk for early renal dysfunction. Recognition of this abnormality in the young may help to prevent the ongoing development of the disease. 相似文献
68.
Michele Zappalorto Marco Salviato Marino Quaresimin 《International Journal of Fracture》2012,176(1):105-112
A closed form solution for the stress fields around a rigid nanoparticle under uniaxial tensile load is provided. The work explicitly accounts for the presence, around the nanoparticle, of an interphase of thickness comparable to the particle size and different elastic properties from those of the matrix. The solution allows one to determine, in closed form, the stress concentration around nanoparticles relevant for fracture and strength assessments of polymer nanocomposites. 相似文献
69.
Da-Wei Luo P. V. Pyshkin Michele Modugno Mike Guidry J. Q. You Lian-Ao Wu 《Quantum Information Processing》2018,17(9):238
We propose an exact mathematical mapping that can be useful for making an analog quantum simulator that uses ion-based systems to realize the many-body electron–electron Coulomb interaction of an electron gas. This exact mathematical mapping allows us to deal with a system that is difficult to solve and control using a potentially more experimentally feasible setup. We show that ions can efficiently simulate electronic Coulomb interactions by using a unitary dilatation transform. The transformation does not need to be physically implemented if only the energy spectrum is desired, eliminating the complexity overhead. This proposal works in any number of dimensions and could be used to simulate different topological phases of electrons in graphene-like structures, by using ions confined in honeycomb lattices. 相似文献
70.
Rollout methodology is a constructive metaheuristic algorithm and its main characteristics are its modularity, the adaptability to different objectives and constraints and the easiness of implementation. Multi-heuristic Rollout extends the Rollout by incorporating several constructive heuristics in the Rollout framework and it is able to easily incorporate human experience inside its research patterns to fulfil complex requirements dictated by the application at hand. However, a drawback for both Rollout and multi-heuristic Rollout is often represented by the required computation time. This paper proposes some alternatives of the full multi-heuristic Rollout algorithm aimed at improving the efficiency by reducing the computational effort while preserving the effectiveness. Namely, we propose dynamic heuristics pruning and candidates reduction strategies. As illustrative case studies, we analyse complex deterministic identical parallel machine scheduling problems showing how Rollout procedures can be used to tackle several additional constraints arising in real contexts. More specifically, we considered both standard (batch production, family set-ups, release, due dates, etc.) and non-standard (machine unavailabilities, maximum campaign size) scheduling constraints. An extensive campaign of computational experiments shows the behaviour of the multi-heuristic Rollout approach and the effectiveness of the different proposed speed-up methods. 相似文献