Use of Kriging Technique to Study Roundabout Performance

Road intersections are dangerous places because of the many conflicting points between motorized and nonmotorized vehicles. In the case of defined traffic volume, several research groups have proved that roundabouts reduced the number of injuries and fatal accident cases. In recent years, many countries have adopted roundabouts as a standard design solution for both urban and rural roads. Several recent studies have investigated the performance of roundabouts, including some with models that calculated the entering flow (Q sub e) as a function of the circulating flow (Q sub c). Most existing models have been constructed with the use of linear or exponential statistical regression. The interpolative techniques in classical statistics are based on the use of canonical forms (linear or polynomial) that completely ignore the correlation law between collected data. As such, the determined interpolation stems from the assumption that the data represent a random sample. In the research reported in this paper, a geostatistical approach was considered: the relationship Q sub e versus Q sub c is supposed to be a regionalized phenomenon. According to that supposition, collected data do not represent a random sample of values but are supposed to be related to each other with a defined law. This recognition allows the realization of interpolation on the basis of the real law of the phenomenon. This paper discusses the fundamental theories, the applied operating procedures, and the first results obtained in modeling the Q sub e versus Q sub c relationship with the application of geostatistics

La qualità negli interventi di ammodernamento e sistemazione della viabilità ordinaria extraurbana

This paper turns its attention to the problems concerning the works which, usually, are not considered impacting on the crossing territory. For this reason they escape to a correct control of their environmental compatibility, control that results to depend on designer sensibility and capacity. This is the major part of the ordinary one way viability, that, very often, move itself in places with their own sensibility. Currently the need to improve existing viability give occasion to think about an environmental compatibility of the whole road constructions, not only the wudge ones, allouding that the improvment became also “environmental”. In this contest, in the environmental qualifications of the interested area, plays a central rule the project of the green arrangement

Distribution of Caulerpa taxifolia var. distichophylla (Sonder) Verlaque, Huisman & Procaccini in the Mediterranean Sea

The Non-Indigenous Species (NIS) Caulerpa taxifolia var. distichophylla (Sonder) Verlaque, Huisman & Procaccini has been reported for the first time in the Mediterranean Sea along the coast of South Turkey. This NIS is actively expanding into the Eastern and Western Mediterranean Sea. In this paper, we present an overview of the current distribution of this alga in the Mediterranean Sea, based on relevant scientific publications, grey literature and personal observations. New records from the Sicilian coast (Italy) are also reported. Caulerpa taxifolia var. distichophylla was found over a wide range of environmental conditions (depth, light and substratum), suggesting a broad ecological plasticity of this alga which makes it a poten- tial threat for the Mediterranean benthic communities. In this respect, artificial structures, often linked to harbours and maritime traffic, seem to provide suitable habitats for this NIS. Since maritime traffic is intense in the Mediterranean Sea, further expansion of C. taxifolia var. distichophylla in this region is to be expected. For this reason, it is very important to build up an overview on the current distribution of the species and its possible pattern of colonisation in relation to environmental conditions, as well as in view of future climate change scenarios

Urban Policies and Mobility Trends in Italian Smart Cities

This study uses indicators to evaluate the progress made by Italian cities in the smart mobility sector, in order to understand how these cities have approached the new guidelines imposed by the European Union, and how they have implemented the European changes. Specifically, this study analyses the evolution of public transportation systems, using a sample of twenty-two Italian cities for three successive time periods (2005, 2010, and 2015). The outcomes identified are then linked to funding provided for the implementation of projects related to smart mobility in the cities studied, in order to verify possible correlations between the growth of these services and European and national financial investments. The data analysis shows remarkable progress in the field of sustainable mobility, especially between 2010 and 2015 as well as how this progress is linked to significant financial support that favours the realization of projects related to smart mobilit

Road signs: walking among shapes and colors

Road signs provide information through the combination of three elements: shape, color and pictogram. The current road signs are projected to ensure safety but are designed for adults and not for children. Kids are not small adults and they have a different perception of reality. While planning of home-school pedestrian routes, it is necessary to create road signs that are comprehensible for children aged 6-14. Therefore the elements of road signs were studied individually. The study revealed that both the knowledge of geometric shapes and colors perception are closely related to age and culture and to the teachings which children are submitted to. In fact, some geometric shapes, like the circle, are perfectly recognized from childhood and others less so, such as the rectangle. Moreover children are attracted to basic colors but they are aware of the existence of pastel colors only with teaching. Finally, pictogram must represent a simple symbol that is easily recognized especially from far away. The message generated by the three elements is understandable by children. In fact, children overcome the phase of syncretism after the age of 6, which corresponds to the phase in which children are unable to analyses and syntheses. The result of the research has allowed to design road signs, both vertical and horizontal, that are able to ensure the safety of home-school routes. A road signs study was conducted for Cagliari’s project on road safety. This project involves the use of questionnaires to verify if the road signs are properly designed

Geostatistical Approach for Operating Speed Modelling on Italian Roads

Injuries are one of the main causes of death according to W.H.O. For this reason the attention of road safety researchers especially regards the study of the relationship between driver and road environment. Several research works show that operating speed is an excellent driver behavior parameter. This article describes a different approach to the classical definition of prediction models for operating speed on horizontal curves. In this paper, the fundamental theories, the applied operating procedures and the first results obtained with the application of Geostatistics are discussed. The mathematical models expressing operating speed in function of horizontal curves characteristics found in International scientific literature, have mainly been built on the basis of Classical Statistics. For this reason, it needs to be pointed out that the interpolative techniques found in Classical Statistics are based upon the use of canonical forms (linear or polynomial regressions) that completely ignore the correlation law between collected data. As such, the determined interpolation stems from the assumption that the data represent a random sample. The models described in this article have instead been created with the geostatistical interpolation technique (i.e. Kriging). This technique allows to obtain the "best" estimates possible because it considers the true correlation law between the measured data. The applied methods are then described along with the results obtained in the field of road safety by applying Geostatistics which, for several years, have been used, with positive results, in all scientific and engineering fields dealing with empirical data analysis and processing

La Meccanizzazione della raccolta del mirto

The plant of the myrtle in past has been always considered one marginal cultivation and of insufficient interest. Only in the last five years it has been knowledge the economic importance for the demanded crescent of liquor of myrtle, product up to now nearly exclusively in Sardinia. Therefore, new sensibility has been developed one and a greater knowledge of the importance of a deepened study more of the cultivation from the biological point of view and the point of view of one rations mechanized harvester of the berries. The aim of the work was that one to characterize an harvester of the berries from the plant, avoiding the damaging of the plant and above all of the fruits that influenced on the quality of the finished product. In this present study they are evidences the comparison between some tests of harvest in turn to obtained and carried out with two different types of harvesters some in relation to the ransom of the plants

The Effect of Cranial Cruciate Ligament Rupture on Range of Motion in Dogs

open3noRange of motion (ROM) is a measure often reported as an indicator of joint functionality. Both the angle of extension and that of flexion were measured in 234 stifle joints of dogs with cranial cruciate ligament (CCL) rupture. The aims of this study were to investigate the correlation between CCL rupture and alterations in the range of stifle joint motion and to determine whether there was a prevalence modification of one of the two angles. All the extension and flexion angles were obtained from clinical records and were analysed in various combinations. A significant relationship was found between normal angles and abnormal angles; concerning the reduction in the ROM, a significant prevalence in the alteration extension angle was found. Of the 234 stifles, 33 (13.7%) were normal in both angles. These results could offer important insights regarding the influence of CCL rupture on compromising the ROM. This awareness could be a baseline for understanding the ability of surgical treatment to restore one angle rather than another angle, to address the choice of treatment and to help physiotherapists in their rehabilitation program.openPinna, Stefania; Lanzi, Francesco; Tassani, ChiaraPinna, Stefania; Lanzi, Francesco; Tassani, Chiar

Emissioni di particolato da bacini sterili esposti all'erosione eolica

The disposal of industrial and mineral processing residues (tailings) represents a major concern for human health and the diverse environmental matrices when considering the impact on soil and groundwater due to leachate filtration through the bottom of tailings basins, as well as the impact on the atmosphere caused by the wind erosion of the exposed surfaces. In fact, under unfavorable meteorological conditions (high temperature, intense solar radiation, low humidity and high wind velocity) the erosion of the dry surfaces may cause the emission of large quantities of fine and extra-fine particles (PM10 and PM2.5). Considering the significance of the issue on a global scale and the increasingly stricter orientation of international environmental policies towards a progressive reduction of harmful emissions generated by industrial activities, the need for reliable modelling tools capable of estimating the contribution of tailing basins to PM air pollution becomes apparent. The research hereby discussed specifically deals with the disposal of the red mud originated from the Bayer process (i.e. production of alumina from bauxite). Experimental emission tests were performed at the Department of Civil and Environmental Engineering and Architecture (DICAAR) of Cagliari University on red mud samples collected at a major Bauxite Residue Disposal Area (BRDA) located in south-eastern Sardinia (Italy). PM emission tests were carried out by means of the Environmental Wind Tunnel (EWT) recently designed and built at DICAAR. Before the emission tests, the red mud samples (particles assemblages and crusts) were prepared through drying processes, in order to simulate the state of the surface at the top of the BRDA (field condition), and wind speed measurements were performed into the wind tunnel to verify the accuracy of the simulated part-depth Atmospheric Boundary Layer (ABL). The emission tests were performed by adjusting the simulated wind speed to account for different intensity of the erosion phenomenon and detecting PM concentrations downstream of the samples with an aerosol monitoring system (DustTrak DRX). The Emission Factor (EF) of the red mud surfaces was calculated from the measured values of PM concentration and wind velocity, as a function of the main affecting variables (red mud water content and wind velocity)

Homocysteine and risk of age-related macular degeneration: a systematic review and meta-analysis

There is still no agreement on total plasma homocysteine (tHcy) role in age-related macular degeneration (AMD), the leading cause of new blindness in industrialized countries. We performed a systematic review and meta-analysis of the published data on the correlation between tHcy and AMD. MEDLINE/PubMed and ISI Web of Sciences searches were performed according to MOOSE guidelines. Case-control studies were eligible for inclusion. Participants and controls were AMD patients and subjects without AMD. The main outcome measure was wet AMD. Homocysteine level was the main exposure variable. Data were pooled using a random-effects model. Twelve case-control studies were identified: 10 assessed wet AMD, four dry AMD, one early AMD, one late AMD, and one any AMD. As for wet AMD, there was a total of 453 cases and 514 controls. Mean tHcy was on average 1.1 μmol/l (95% confidence interval [CI] = 0.96-1.25) greater in wet AMD cases, but there was evidence of extreme between-study heterogeneity (p < 0.001, I2 = 91.8%). In a model homogenous for age, including six wet AMD studies (214 cases, 274 controls), mean tHcy was on average 0.58 μmol/l (95% CI = 0.35-0.73) greater in the case group, a not statistically significant result (p = 0.144) associated with moderate heterogeneity (I2 = 39.2%). Our meta-analysis indicates that there is some weak evidence that increased tHcy might be associated with wet AMD; however, this result should be interpreted cautiously, because of a marked between-study heterogeneity and the possible effect of publication bias. Future studies, preferably of cohort design, are necessary before any firm conclusions on the putative role of increased tHcy on AMD can be drawn