Adhesive connections in timber: a comparison between rough and smooth wood bonding surfaces

The use of adhesive anchors for wooden constructions is an efficient technology to connect and design timber members in new timber structures and to rehabilitate the damaged structural members of historical buildings. Due to the lack of standard regulation in this specific area of structural design, designers’ choices are still supported by test analysis that enables knowledge, and the prediction, of the structural behaviour of glued in rod joints. The paper outlines an experimental research activity aimed at identifying the tensile resistance capacity of several new adhesive joint prototypes made of epoxy resin, steel bar and timber, Oak and Douglas Fir species. The development of new adhesive connectors has been carried out by using epoxy to glue stainless steel bars into pre-drilled holes, characterised by smooth and rough internal surfaces, in timber samples. The realization of a threaded contact surface using a specific drill bit has led to an improved bond between wood and epoxy. The applied changes have also reduced the cost of the joints' production. The paper presents the results of this parametric analysis and a Finite Element analysis that enables identification and study of the internal stress distribution in the proposed adhesive anchors

Communities of consumption and Made in Italy

The interest towards the role of user communities in innovation has grown among scholars and practitioners. Research has explored the role of communities in high‐tech and medium‐tech industries with a focus on innovation in the functional dimension of products. Less attention has been devoted to user communities' contribution in industries such as fashion, where innovation is much more related to communication and aesthetics. This paper provides a preliminary set of concepts and working hypotheses regarding the contribution of communities to the non‐functional dimension of product innovation in low‐tech industries and to the relationship between user involvement in brand communities and their incentives to contribute to innovation both tangible and intangible. The paper discusses two case studies of Made in Italy enterprises that refer to communities for their innovation strategies

CleAir monitoring system for particulate matter. A case in the Napoleonic Museum in Rome

Monitoring the air particulate concentration both outdoors and indoors is becoming a more relevant issue in the past few decades. An innovative, fully automatic, monitoring system called CleAir is presented. Such a system wants to go beyond the traditional technique (gravimetric analysis), allowing for a double monitoring approach: the traditional gravimetric analysis as well as the optical spectroscopic analysis of the scattering on the same filters in steady-state conditions. The experimental data are interpreted in terms of light percolation through highly scattering matter by means of the stretched exponential evolution. CleAir has been applied to investigate the daily distribution of particulate matter within the Napoleonic Museum in Rome as a test case

GALNT2 as a novel modulator of adipogenesis and adipocyte insulin signaling

Background/objectives: A better understanding of adipose tissue biology is crucial to tackle insulin resistance and eventually coronary heart disease and diabetes, leading causes of morbidity and mortality worldwide. GALNT2, a GalNAc-transferase, positively modulates insulin signaling in human liver cells by down-regulating ENPP1, an insulin signaling inhibitor. GALNT2 expression is increased in adipose tissue of obese as compared to that of non-obese individuals. Whether this association is secondary to a GALNT2-insulin sensitizing effect exerted also in adipocytes is unknown. We then investigated in mouse 3T3-L1 adipocytes the GALNT2 effect on adipogenesis, insulin signaling and expression levels of both Enpp1 and 72 adipogenesis-related genes. Methods: Stable over-expressing GALNT2 and GFP preadipocytes (T 0 ) were generated. Adipogenesis was induced with (R+) or without (R−) rosiglitazone and investigated after 15 days (T 15 ). Lipid accumulation (by Oil Red-O staining) and intracellular triglycerides (by fluorimetric assay) were measured. Lipid droplets (LD) measures were analyzed at confocal microscope. Gene expression was assessed by RT-PCR and insulin-induced insulin receptor (IR), IRS1, JNK and AKT phosphorylation by Western blot. Results: Lipid accumulation, triglycerides and LD measures progressively increased from T 0 to T 15 R- and furthermore to T 15 R+. Such increases were significantly higher in GALNT2 than in GFP cells so that, as compared to T 15 R+GFP, T 15 R- GALNT2 cells showed similar (intracellular lipid and triglycerides accumulation) or even higher (LD measures, p < 0.01) values. In GALNT2 preadipocytes, insulin-induced IR, IRS1 and AKT activation was higher than that in GFP cells. GALNT2 effect was totally abolished during adipocyte maturation and completely reversed at late stage maturation. Such GALNT2 effect trajectory was paralleled by coordinated changes in the expression of Enpp1 and adipocyte-maturation key genes. Conclusions: GALNT2 is a novel modulator of adipogenesis and related cellular phenotypes, thus becoming a potential target for tackling the obesity epidemics and its devastating sequelae

A Robust Tucker3 Model for Compositional Data

Double counting is inherent to the output concept, therefore it is preferable to use manufacturing value added (MVA) instead to measure the manufacturing production. While the issue of double counting in production statistics is successfully addressed by using MVA, commodity exchange in trade data is still measured as output. The relevance of value added has increased in the recent years due to the unbundling of the production process, where different stages of value chain take place in different countries. We want to represent the export statistics through value added to output ratio using data from international statistical databases. The data sets considered are organized by country, commodity or activity and year (activities are classified according to the International Standard Industrial Classification of all economic activities (ISIC)) and thus they are three-way compositional data.\ud Different methods exist for analysis of multi-way data and we choose Tucker3 because it provides a compromise between parsimonious and flexible models. The Tucker3 method as most of the N-way methods is based on alternating least squares (ALS) which makes it vulnerable to the presence of outliers in the data. Even a single outliying data point can\ud strongly influence the resulting model and the conclusions based on it. A robust version of Tucker3 was presented by Pravdova et al. (2001) but it suffers from two main deficiencies. First of all the robust initialization of the algorithm is based on MCD which will not work in high dimensions. And secondly, the method is not suitable for applying on compositional data. We propose to select the initial subset using robust PCA and to transform the compositional data applying ilr transformation (Egozcue et al., 2003). Furthermore, since to our knowledge there is no readily available software for computing robust Tucker3 models, we provide\ud implementation of the proposed algorithm in R. The method is compared to its competitors both in terms of its efficiency and the computational effort needed

Joint Biplots for CoDa

Compositional data (CoDa) consist of vectors of positive values summing to a unit, or in general, to some fixed constant for all vectors. They appear as proportions, percentages, concentrations, absolute and relative frequencies. Sometimes, compositions arise from non-negative data (such as counts, area, weights, volume) that have been scaled by the total of the components because the analyst is not interested in the total sum of the vector. The multidimensional analysis of this kind of data requires a careful consideration because the sample space for CoDa is the simplex. The first consistent methodological proposal to deal with CoDa was proposed by Aitchison (1986) when he introduced the log-ratio approach. Basically, the idea that this approach conveys is to move from the simplex space to the real space by using log.ratio transformations, applying standard statistical methods, and finally, by means of an inverse log-ratio transformation, to interpret the results in the simplex space. Starting from this paper, pairwise, centered, additive and isometric log-ratio transformations, in short plr, clr, alr (Aitchison, 1986) and ilr respectively, are proposed in literature (Egozucue et al., 2003). In the context of dimension-reducing techniques, Aitchison (1983) proposed applying principal component analysis (PCA) after having applied a centered log-ratio (clr) transformation to CoDa. Aitchison and Greenacre (2002) suggested an adaptation of the biplot to CoDa. The biplot is a well established graphical aid in other branches of statistical analysis and can prove to be a useful exploratory and expository tool for compositions. In literature many papers on dimensional-reduction techniques for CoDa are proposed. Based on log-ratio strategy, Gallo (2012a, 2012b, 2013) recently proposed to use three-mode analysis of compositional data.\ud Starting from Gallo (2012b), we propose using of plr and clr joint biplots. Where in some cases the plr joint biplot is the only ones that show clearly the correlations

Robots for Exploration, Digital Preservation and Visualization of Archeological Sites

Monitoring and conservation of archaeological sites are important activities necessary to prevent damage or to perform restoration on cultural heritage. Standard techniques, like mapping and digitizing, are typically used to document the status of such sites. While these task are normally accomplished manually by humans, this is not possible when dealing with hard-to-access areas. For example, due to the possibility of structural collapses, underground tunnels like catacombs are considered highly unstable environments. Moreover, they are full of radioactive gas radon that limits the presence of people only for few minutes. The progress recently made in the artificial intelligence and robotics field opened new possibilities for mobile robots to be used in locations where humans are not allowed to enter. The ROVINA project aims at developing autonomous mobile robots to make faster, cheaper and safer the monitoring of archaeological sites. ROVINA will be evaluated on the catacombs of Priscilla (in Rome) and S. Gennaro (in Naples)

Monitoreo del servicio a tiempo real que prestan las estaciones permanentes de Mendoza

Debido a los estudios realizados en el 2012 respecto de la calidad operativa que brinda el servicio de posicionamiento a tiempo real utilizando NTRIP en Argentina, en el 2013 se optó por monitorear continuamente el servicio que prestan las estaciones permanentes (EP) ubicadas en Mendoza. Objetivo: Analizar la continuidad, integridad y seguridad en la transmisión de correcciones diferenciales NTRIP, desde las EP de GPS (Global Positioning System o sistema de posicionamiento global) server ubicadas en la provincia de Mendoza.Fil: Di Marco, L. N.. Universidad "Juan Agustin Maza". Facultad de Ingenieria; ArgentinaFil: Mackern, M. V.. Universidad Nacional de Cuyo. Facultad de Ingenieria; Argentina. Universidad "Juan Agustin Maza". Facultad de Ingenieria; ArgentinaFil: Camisay, Maria Fernanda. Universidad "Juan Agustin Maza"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mateo, Maria Laura. Universidad Nacional de Cuyo. Facultad de Ingenieria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Científico Tecnológico Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentin

Resin connectors in timber

The use of Glued In Rod joints for wooden constructions is an efficient technology to connect and design members in new timber structures and to rehabilitate the damaged structural elements of historical buildings. The major issue concerning the use of adhesive anchors in timber is the lack of a standard regulation in the current Eurocode 5 for timber structures. Due to the gap in knowledge of this specific topic in engineering structural design, designers' choices are still supported by test analysis which enables knowledge, and the prediction, of the structural behaviour of Glued In Rod joints. Over the last 30 years, research studies have suggested diverse and contradictory procedures for the prediction of the withdrawal capacity of adhesive anchors in timber whose application led to the relay of inconsistent information about the use of Glued In Rods in the timber engineering field. The presented research work is aimed at clarifying the contradictory nature amongst existing design rules and at proposing a correct design procedure to assess the load bearing capacity of adhesive anchors in timber, whilst also taking into consideration the high product-dependency which Glued In Rod connections are characterised by. Moreover, the thesis investigates the development of new prototypes of resin connectors in timber through the identification of innovative technical solutions in order to achieve an improved structural performance of the studied adhesive joints. An extensive experimental program has been carried out on 'traditional' and new prototypes of adhesive anchors in timber, identified respectively by smooth-cylindrical and rough-threaded internal boreholes in which 8 mm steel rods have been glued by the use of low and high viscosity epoxy resins. The tensile performance of more than 100 samples of single adhesive anchors made from solid timber and glulam has been tested by pull-compression tests in confined test regimes, in both cold states and at elevated temperatures. Experimental findings suggest that in cold states and in restrictive manufacturing conditions, the adoption of the new prototype of Glued In Rods, characterised by the presence of a threaded and rough internal bonding surface, can simultaneously provide an increase of up to 12% in the withdrawal capacity and a decrease in the joint’s cost, due to a significant reduction (30-40%) in the use of epoxy resins when compared to 'traditional' Glued In Rods. Conversely, a change in the internal borehole's shape does not affect the thermal performance of the connections, highlighting that the structural performance of a Glued In Rod joint at elevated temperatures is highly dependent on the thermal properties (Heat Deflection Temperature) of the resin used to assemble the connection. Regarding the design of the withdrawal capacity of Glued In Rods, a critical literature review revealed that previous design equations all stemmed from research studies based on the application of different methods and investigative methodologies for both the manufacturing and the testing phases; hence, they cannot be used to produce general statements on the structural behaviour of Glued In Rods. The thesis filled the gap in knowledge about the design of adhesive anchors in timber by proposing a simple and innovative design process mainly composed of two phases: the identification of a specific bond strength parameter which has to be determined by standard experiments and provided by adhesive manufactures, and the presentation of a mathematical equation which allows the calculation of the withdrawal capacity of a single adhesive anchor in timber by knowing the aforementioned bond strength parameter and joint's geometrical features. This research thesis provides critical information about all the stages that the process of using Glued In Rod connections involves (manufacturing, testing, installation and design) identifying priority actions to be undertaken for the implementation of European technical guidelines and design methods for the use of adhesive anchors in the timber engineering field

A new perspective for the training assessment: Machine learning-based neurometric for augmented user's evaluation

Inappropriate training assessment might have either high social costs and economic impacts, especially in high risks categories, such as Pilots, Air Traffic Controllers, or Surgeons. One of the current limitations of the standard training assessment procedures is the lack of information about the amount of cognitive resources requested by the user for the correct execution of the proposed task. In fact, even if the task is accomplished achieving the maximum performance, by the standard training assessment methods, it would not be possible to gather and evaluate information about cognitive resources available for dealing with unexpected events or emergency conditions. Therefore, a metric based on the brain activity (neurometric) able to provide the Instructor such a kind of information should be very important. As a first step in this direction, the Electroencephalogram (EEG) and the performance of 10 participants were collected along a training period of 3 weeks, while learning the execution of a new task. Specific indexes have been estimated from the behavioral and EEG signal to objectively assess the users' training progress. Furthermore, we proposed a neurometric based on a machine learning algorithm to quantify the user's training level within each session by considering the level of task execution, and both the behavioral and cognitive stabilities between consecutive sessions. The results demonstrated that the proposed methodology and neurometric could quantify and track the users' progresses, and provide the Instructor information for a more objective evaluation and better tailoring of training programs. © 2017 Borghini, Aricò, Di Flumeri, Sciaraffa, Colosimo, Herrero, Bezerianos, Thakor and Babiloni