5,600 research outputs found
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
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
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
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
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
Preparation, performances and reaction mechanism for the synthesis of H2O2 from H2 and O2 based on palladium membranes
Taking a critically informed approach, this innovative text examines emerging approaches to social procurement within the context of New Public Government (NPG), and examines the practices of social procurement across Europe, North America and Australia. Considering both the possibilities and limitations of social procurement, and the types of value it can generate, this book also provides empirically driven insights into the practicalities of 'triple bottom line' procurement, the related challenges of measuring social value and the management of both the strategic and operational dimensions of procurement processes. As such it will be invaluable reading for all those interest in social services, public governance and social enterprise
Sintesi stereoselettiva di piridilammine
Ammino piridine chirali hanno dimostrato la loro validità come leganti per la formazione di
complessi metallici utilizzati nella catalisi asimmetrica.
Tra i possibili approcci alla sintesi di questi composti noi abbiamo investigato la riduzione
diastereoselettiva di N-sostituite (p-totil e tert-butil) piridil chetimmine con una serie di
agenti riducenti (NaBH4, L-Selectride, DIBAL, 9-BBN) in diverse condizioni di reazione
Additive Manufacturing applications within food industry: An actual overview and future opportunities
The food sector is one of the major economic sectors in Europe and beyond and produces nutrition for the world population. Food industry has a unique role in all countries economy as it is essential to people lives. In Europe it is the largest manufacturing sector in terms of value added, turnover and employment. On the other hand, several worldwide economic-social-technological trends are pushing organizations to embrace innovation as an integrated part of their corporate strategy, and to offer customized products tailored to market targets need. Embracing innovation became strategic in order to create a sustainable competitive advantage and to stay ahead of the competition in every industry, even in food one. Today, among all the most cutting-edge technologies, Additive Manufacturing (AM) has the potential to develop business paradigms to face an ever changing demand. AM comprises a group of technologies whose initial inception occurred over thirty years, characterized by a layer upon layer production directly from Computer-Aided Design (CAD) data. Over the past few years AM development has increased exponentially and has expanded to include new areas of research. Within all the innovative applications, one of the most promising under respect of social impacts and progress, has proved to be the technological application in the food industry. This scientific work aims at finding out potential touching points between additive manufacturing technologies and food market, either consumer and industrial, focusing on the actual and future applications
- …
