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Pedestrian Safety Around Elementary SchoolsCicek, Bunyamin Erkan 01 September 2009 (has links) (PDF)
This study establishes pedestrian safety focused environment around elementary schools. In order to reach this objective 3 consecutive goals are fulfilled / firstly / proposing, a newly designed black spot analysis, &ldquo / Behavioral Black Spot Analysis&rdquo / , secondly / documenting pedestrian behavior around black spots, and finally stimulating effective interventions around elementary schools. This study proposes a newly designed methodology / &ldquo / Behavioral Black Spot Analysis&rdquo / which is namely based upon pedestrians&rsquo / route choice and risk perception statements. Additionally it is observed that students choose the shortest route on their way. &ldquo / Behavioral Black Spot Analysis&rdquo / reveals that traffic flows, pedestrian visibility, vehicle visibility, waiting time, road width are most important parameters of pedestrians&rsquo / perception of traffic safety. Results of unobtrusive observations indicate that interventions have significant effect on vehicle speed, number of conflicts, yielding behavior of drivers, total number of cars forming a queue, number of pedestrians stopping on the curb, head movements, crossing angles, crossing tempos, and crossing distances of pedestrians. Behind this interventions affects pedestrians&rsquo / waiting time in negative manner. Recommendations for pedestrian safety interventions are suggested.
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Quality on single-track railway lines with passenger traffic : Anlytical model for evaluation of crossing stations and partial double-tracksLindfeldt, Olov January 2007 (has links)
<p>Railway transportation is showing a substantial increase. Investments in new infrastructure, new fast and comfortable vehicles, and high frequency of service are important factors behind the increase.</p><p>Infrastructure configuration and timetable construction play important roles in the competitiveness of railway transportation. This is especially true on single-track lines where the travel times and other timetable related parameters are severely restricted by crossings (train meetings). The crossings also make the lines’ operation more sensitive to disturbances.</p><p>Since the major part of the Swedish railway network is single-track it is of great interest to examine the relationships between operation properties, such as travel times and reliability, and infrastructure configuration on single-track lines. The crossings are the core feature of single-track operation and this thesis focuses on the crossing time, i.e. the time loss that occurs in crossing situations.</p><p>A simplified analytical model, SAMFOST, has been developed to calculate the crossing time as a function of infrastructure configuration, vehicle properties, timetable and delays for two crossing trains. The effect of possible surrounding trains is not taken into account and all kinds of congestion effects are thus excluded from evaluation. SAMFOST has been successfully validated against the simulation tool RailSys, which shows that this type of simplified model is accurate in non-congested situations.</p><p>A great advantage of disregarding congested situations is that analysis is independent of timetable assumptions. The model also explicitly shows the effect of punctuality, which is of particular importance on single-track lines where the interdependencies between trains are strengthened by the crossings.</p><p>For the same reason, the timetable is severely constrained. Nonetheless, there is often a need for changes of the timetable (crossing pattern). The thesis proposes three simple measures of timetable flexibility, all based on assigned crossing time requirements. Together, these measures can be used to evaluate how infrastructure configuration, vehicle properties, punctuality etc affect possibilities to alter the timetable.</p><p>As an example of its application, SAMFOST has been used to evaluate the effect of shorter inter-station distance, partial double-track and combined crossing and passenger stop. These measures affect the operational properties quite differently.</p><p>More crossing stations result in a minor decrease in travel time (lower mean crossing time) but significantly higher reliability (lower crossing time variance). These effects are independent of punctuality, which is a valuable property.</p><p>A partial double-track results in shorter travel times and in some cases also higher reliability. Both effects are strongly dependent on punctuality and high punctuality is needed to achieve high effects.</p><p>A combined crossing and passenger stop results in a situation similar to that of a partial double-track. In this case it is important to point out that the assignment of time supplements in the timetable should be directly correlated to punctuality in order to achieve good operation.</p>
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Application of Design for Safer Urban Roads and Junctions: Selected CountermeasuresSanca, Michal January 2002 (has links)
<p>Road design with focus to safety has been extensively developed in last decades in Nordic and some other EU countries with the main aim to achieve a decrease in a number of accidents and fatalities on the roads. These countries gained many valuable experiences, but they had to sacrifice great effort, expenses, and time to reach the present art-of-state. The purpose of the Master’s Thesis is to review some design approaches with focus to safety and discuss the general way that they may be applied. </p><p>The Master’s Thesis studies safety in three levels: (i) general - design standards, national safety policies and road hierarchy; (ii) local authority and road administrator; and (iii) three specific safety countermeasures - junctions, pedestrian crossings and traffic calming. </p><p>The first part of Master’s Thesis describes the general road design standards background and their art of state. Furthermore, it discusses the new approaches in road design standard such as Dutch classification of road standards. Safety policies and programs are discussed and the concept of human imperfection is explained. Road safety policy and road hierarchy in Sweden and Denmark is described. </p><p>The second part is devoted to the planning process on local authority and road administrator level. The phases of planning process are described. Special attention is paid to ranking process when choosing most effective countermeasures, next to black spot programs and also to public attitudes to safety countermeasures. </p><p>The focus of the last part is in specific designs for safer road environment. There are discussed three groups of road facilities and countermeasures; unctions, pedestrian crossings and traffic calming. The cost, effectiveness, suitability, possible side effects and other properties of individual types of countermeasures are discussed.</p>
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Crossing borders despite conflict : The role of communication routesMohlin, Henrik, Muratovic, Fazila January 2007 (has links)
<p>Can cross-border interaction: interpersonal, economic, and otherwise, help ease relations between neighbouring political entities facing conflicts of interest and other differences?</p><p>1. How and why are border crossing communication routes created and maintained?</p><p>2. Under what circumstances are they used and how?</p><p>3. In what ways do they alter the conditions of a conflict between the parties that they link?</p><p>4. How do governments relate to the communication route and in what ways do they fit it into their policies?</p><p>Seeking to reconcile the theories of the international system advanced by Hedley Bull and John W. Burton, we conduct a comparative case study, based on contemporary media and scholarship, of the situations regarding Senegal and the Gambia, as well as the two de facto (if not de jure) republics of Cyprus to answer these questions. Having sought to estimate the causes and effects of border crossing, we find that host factors, in particular divergent economies and the utilization of international partners, may in fact come to stem from the issues of border-crossing activity and contribute to complicating existing conflicts rather than resolve them.</p>
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The Influence of Roads on the Florida PantherSchwab, Autumn C. 03 April 2006 (has links)
The Florida panther (Puma concolor coryi) is a relatively well studied species, but some aspects of its habitat requirements remain poorly understood. While it has been well established that the most important threat to panthers include limited habitat area and continued habitat loss and fragmentation, the importance of roads in this context has not been determined. The goal of this research is to determine the influence of roads on the movement patterns of the Florida panther. Panther telemetry data from 1981 until 2003 was used, as well as detailed road networks and vegetation maps. The influence of roads on individual panthers was determined through an analysis of: 1) vehicular mortality; 2) road crossing behavior; 3) road barrier effects; and 4) effectiveness of preventative measures. Results indicate that vehicle collisions continue to be a major threat to the Florida panther population, specifically adult males. Major roads form more of a barrier to movement than minor roads, but females are affected more than males. The combination of wildlife underpasses and high right-of-way fencing on I-75 has been extremely effective at vehicular mortality prevention, but the roadway remains a major barrier, particularly for female panthers. This has essentially segregated the movement of the sexes and has fragmented not only the limited habitat of the Florida panther, but also segments of the adult population critical to the propagation of the species.
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4d Spectra from BPS Quiver DualitiesEspahbodi, Sam 26 September 2013 (has links)
We attack the question of BPS occupancy in a wide class of 4d N = 2 quantum field theories. We first review the Seiberg-Witten approach to finding the low energy Wilsonian effective action actions of such theories. In particular, we analyze the case of Gaiotto theories, which provide a large number of non-trivial examples in a unified framework. We then turn to understanding the massive BPS spectrum of such theories, and in particular their relation to BPS quivers. We present a purely 4d characterization of BPS quivers, and explain how a quiver's representation theory encodes the solution to the BPS occupancy problem. Next, we derive a so called mutation method, based on exploiting quiver dualities, to solve the quiver's representation theory. This method makes previously intractable calculations nearly trivial in many examples. As a particular highlight, we apply our methods to understand strongly coupled chambers in ADE SYM gauge theories with matter. Following this, we turn to the general story of quivers for theories of the Gaiotto class. We present a geometric approach to attaining quivers for the rank 2 theories, leading to a very elegant solution which includes a specification of quiver superpotentials. Finally, we solve these theories by an unrelated method based on gauging flavor symmetries in their various dual weakly coupled Lagrangian descriptions. After seeing that this method agrees in the rank 2 case, we will apply our new approach to the case of rank n. / Physics
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Lietuvos juodmargių ir jų mišrūnų su Šarole mėsinės savybės ir mėsos kokybė / Beef meat production and quality of the Lithuanian Black-and-White cattle and their hybrids with the cattle of CharolaisUrbanavičiūtė, Asta 16 March 2006 (has links)
The aim of work – to determine efficienty of the Lithuanian Black-and-White cattle crossing with Charolais bull. The task of research: 1.To analyse the literature about the crossing Lithuanian Black-and-White caws with Charolais bull. 2.To determine the influence of Charolais bull on beef meat production and quality of Lithuanian Black-and-White cattle. Conclusions: 1.Charolais bulls were found to improve the weight of Lithuanian Black-and-White cattle at 18 month of age by 38.5 kg or 7.6 % (P>0,05) and reduced feed conversion per weight gain unit by 8.2 %. 2.The daily gain of the Charolais hybrids bulls was by 8.0 % bigger than that of the pure-blooded Lithuanian Black-and-White bulls. 3.Control slaughters indicated the bigger carcass mass for Charolais hybrids which was 20.7 kg, or 7.8 % bigger than the carcass mass of the pure-blooded Lithuanian Black-and-White young bulls. 4.Hybrids had a 1.5 % better carcass output, 4.0 % better ham output, and 2.4 % better output of ham edible parts in carcass, by 0.65 bigger the coefficient of succulence of this part of carcass and by 42.94 cm² bigger area of loin lean. 5.Crossbreeding had no significant influence on meat quality. A tendency was observed to lower meat pH, higher shear force and a better amino acids triptophan and oxyproline ratio 5.47 of hybrids (P<0,005). 6.It has been concluded that it is useful to use Charolais bulls for crossing with Lithuanian Black-and-White cattle of milk type.
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Combining Similarity Transformed Equation of Motion Coupled Cluster (STEOM-CC), Vibronic Coupling models, and Spin-Orbit Coupling: Towards a First Principle Description of Intersystem CrossingSous, John January 2013 (has links)
Electronic Structure Theory has led to a variety of developments and applications. In the Nooijen group the focus is on the development and use of Coupled Cluster based approaches. Coupled Cluster is a very strong and accurate approach to the quantum mechanical problem. The research results presented in the thesis testify to the Similarity Transformed Equation of Motion Coupled Cluster (STEOM-CC) for being a very accurate and yet computationally inexpensive approach for excited states. This study reveals new features about STEOM and provides promise regarding future improvement in the methodology. STEOM can be used as the first step in the construction of the Vibronic model, which is a strong tool to move to paradigms beyond the Born-Oppenheimer approximation. Spin-Orbit Coupling (SOC) is a very important ingredient required to study relativistic phenomena and its quantum mechanical implementation for many body systems is not straightforward. The most widely used SOC operator in Chemical Physics is the Breit-Pauli operator, which requires employing non-trivial approximations to the Dirac equation to adapt the theory to many body systems. The integration of electronic structure approaches, Vibronic Coupling, and SOC is essential to study the phenomenon of intersystem crossing (transition between spin states) in fine detail. In this thesis a computational benchmark of STEOM is discussed, while the frameworks of Vibronic Coupling and Spin-Orbit Coupling (SOC) are considered on a theoretical level.
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GEOREFERENCED TREES AND THE PHYLOGENETIC SIMILARITY OF BIOLOGICAL COMMUNITIESParks, Donovan 31 July 2012 (has links)
Culture-independent DNA sequencing is being used to recover genetic material directly from environmental samples. This has spurred large-scale community efforts to catalogue the diversity of life and its geographic distribution using molecular data. These initiatives stand to revolutionize our understanding of the processes that shape biodiversity and may ultimately provide critical information for setting public health, environmental, and economic policies. To achieve these aims new tools are required to effectively explore these large biogeographic datasets.
This thesis introduces a novel technique for visualizing hierarchically organized data in a geographic context that illustrates the influence of a geographic or environmental gradient on the phylogenetic relationships between organisms or the similarity of biological communities. This technique is incorporated into GenGIS, open-source software that supports the integration of digital map data with genetic sequences and environmental information from multiple sample sites. GenGIS addresses the need for an interactive geospatial analysis environment capable of handling large biogeographic datasets where a wealth of sequence data is available for each sample site. This is accomplished through a rich set of analysis options that produce georeferenced visualizations for data exploration and hypothesis generation. Studies conducted by myself and other research groups have used GenGIS to investigate the diversity of viruses, bacteria, plants, animals, and even language families.
I then explore measures of beta diversity that aim to assess the influence of geographic or environmental gradients on the similarity of biological communities. This thesis examines phylogenetic beta-diversity measures that determine community variation by considering the relationships between organisms in a phylogenetic tree. A large comparative study is performed in order to assess specific properties and performance characteristics of these measures. Many measures of phylogenetic beta diversity were found to be robust to sequence clustering, the addition of an outlying basal lineage, root placement, and the presence of rare organisms. Additionally, performance was found to differ substantially under different models of community variation. This thesis then describes how an important class of phylogenetic beta-diversity measures can be calculated over phylogenetic networks in order to account for uncertainty and conflict in inferred ancestral relationships.
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Using under-road tunnels to protect a declining population of long-toed salamanders (Ambystoma macrodactylum) in Waterton Lakes National ParkPagnucco, Katie Unknown Date
No description available.
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