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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Pedestrian Safety Around Elementary Schools

Cicek, 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.
2

The Influence of Roads on the Florida Panther

Schwab, 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.
3

Challenges of Conserving a Wide-ranging Carnivore in Areas with Dense Road Networks

Bencin, Heidi L. January 2018 (has links)
No description available.
4

Interactive Visual Analytics for Agent-Based simulation : Street-Crossing Behavior at Signalized Pedestrian Crossing

Zheng, Jiaqi January 2019 (has links)
To design a pedestrian crossing area reasonably can be a demanding task for traffic planners. There are several challenges, including determining the appropriate dimensions, and ensuring that pedestrians are exposed to the least risks. Pedestrian safety is especially obscure to analyze, given that many people in Stockholm cross the street illegally by running against the red light. To cope with these challenges, computational approaches of trajectory data visual analytics can be used to support the analytical reasoning process. However, it remains an unexplored field regarding how to visualize and communicate the street-crossing spatio-temporal data effectively. Moreover, the rendering also needs to deal with a growing data size for a more massive number of people. This thesis proposes a web-based interactive visual analytics tool for pedestrians' street-crossing behavior under various flow rates. The visualization methodology is also presented, which is then evaluated to have achieved satisfying communication and rendering effectiveness for maximal 180 agents over 100 seconds. In terms of the visualization scenario, pedestrians either wait for the red light or cross the street illegally; all people can choose to stop by a buffer island before they finish crossing. The visualization enables the analysis under multiple flow rates for 1) pedestrian movement, 2) space utilization, 3) crossing frequency in time-series, and 4) illegal frequency. Additionally, to acquire the initial trajectory data, Optimal Reciprocal Collision Avoidance (ORCA) algorithm is engaged in the crowd simulation. Then different visualization techniques are utilized to comply with user demands, including map animation, data aggregation, and time-series graph. / Att konstruera ett gångvägsområde kan rimligen vara en krävande uppgift för trafikplanerare. Det finns flera utmaningar, bland annat att bestämma lämpliga dimensioner och se till att fotgängare utsätts för minst risker. Fotgängarnas säkerhet är särskilt obskyrlig att analysera, eftersom många människor i Stockholm korsar gatan olagligt genom att springa mot det röda ljuset. För att klara av dessa utmaningar kan beräkningsmetoder för bana data visuell analys användas för att stödja den analytiska resonemangsprocessen. Det är emellertid ett oexplorerat fält om hur man visualiserar och kommunicerar gataövergången spatio-temporal data effektivt. Dessutom måste rendering också hantera en växande datastorlek för ett mer massivt antal människor. Denna avhandling föreslår ett webbaserat interaktivt visuellt analysverktyg för fotgängares gatöverföring under olika flödeshastigheter. Visualiseringsmetoden presenteras också, som sedan utvärderas för att ha uppnått tillfredsställande kommunikation och effektivitet för maximal 180 agenter över 100 sekunder. Vad beträffar visualiseringsscenariot, väntar fotgängare antingen på det röda ljuset eller tvärs över gatan; alla människor kan välja att stanna vid en buffertö innan de slutar korsa. Visualiseringen möjliggör analysen under flera flödeshastigheter för 1) fotgängarrörelse, 2) rymdutnyttjande, 3) korsfrekvens i tidsserier och 4) olaglig frekvens. För att förvärva den ursprungliga bana-data är Optimal Reciprocal Collision Avoidance (ORCA) algoritmen förknippad med folkmassimuleringen. Därefter utnyttjas olika visualiseringstekniker för att uppfylla användarnas krav, inklusive kartanimering, dataaggregering och tidsserier.
5

Collaborative Boundary Crossing Behaviours Of Product Development Teams : Role Of Direct And Indirect Factors

Randhir, R P 07 1900 (has links)
Emerging markets are fraught with uncertainty, diverse global players, rapid technological change, wide-spread price wars, and seemingly endless reorganization (Ilinitch, 1996). These changes have presented challenges to organizations in the form of shorter product cycles, increased segment fragmentation, blurring industry boundaries, breaking corporate hierarchies, and increased interdependence of world markets (Ozsomer et. al., 1991). Organizations are responding to competition by capitalizing on global policies and adopting self-directed teams and horizontal structures that enhance external activities. To do this organizations are getting conscious of the boundaries they are operating in. With hyper competition and globalization organizations blur boundaries to gain maximum business opportunity from other geographic boundaries. For this to happen organizations must engage in boundary crossing behaviour. Competition is also managed by focussing on bringing out new products to the market. Product development (PD) is critical because new products are becoming the nexus of competition for firms (Clark and Fujimoto, 1991). They are the means by which members of organizations diversify, adapt, and even reinvent their firms to match evolving market and technological conditions (Schoonhoven et. al., 1990). This calls for a closer look at boundary crossing behaviour as part of the external activity during PD. The studies carried out in the process of PD identify external activity orientation as important criteria for success (Brown and Eisenhardt, 1995). PD processes involve project management activity. Unlike other processes of an organization, PD is a knowledge intensive activity, which brings together individuals having different skill sets and mindsets. These individuals need to interact regularly to understand and coordinate their activities. The non-routine nature of the process makes boundary-crossing activity more critical for successful PD. This thesis focuses on the boundary crossing behaviours performed by PD teams. Literature review showed that external activities play a crucial role in PD (Calantoue and Di Benedetto 1990a, b; Griffin and Hauser 1992; Olson et. al., 1995; Song et al., 2000; Souder 1987). The importance of external activities for successful project development was shown by Allen (1971, 1977) based on his seminal work on communication and organizations. He showed that R&D team’s frequency of communication within the team has no relationship to performance, while increased communication between teams and other parts of the laboratory was strongly related to project performance. Teams carrying out complex tasks in uncertain environments were found to perform higher levels of external activities (Ancona and Caldwell 1992). External activity was found to result in high percentages of successful projects and sales derived from new products (Cooper 1984; Dougherty 1987; Ancona and Caldwell, 1992; Ancona, 1990; Sheremata 2002). PD is an activity with high uncertainty. The external activities that are performed by PD teams and their nature of relationships shared are variously classified as interactive and collaborative behaviour (Kahn 1996). Underlying this classification is a dichotomous behaviour where in the former embodies presence of informal behaviour between partners, while the latter embodies formal behaviour. Further research on these behaviours have shown that informal type of external activity also known as collaborative behaviour plays an important role in the successful development of products. Collaboration represents the unstructured, affective nature of interdepartmental relationships. They were found to result in improved product development. A study on software product development teams by Kraut and Streeter(1995) also showed the importance of informal behaviour. He found that product development requires personal communication across functional boundaries to cope with uncertainty. The external activities performed by PD teams were also found to be influenced by variables like product development life cycle (Brodbeck, 2001; Sawyer & Guinan, 1998; Boehm, 1987), informal groups (Hirschhorn and Gilmore, 1992), awareness, (Pinto and Slevin, 1987), and open climate (Ashkenas et. al., 1990). After identifying the missing gaps in gaps were the objectives of the study was defined. The objectives of the study are as follows: To understand the interactive and collaborative boundary crossing behaviour of product development teams To study the difference in boundary crossing behaviour of horizontal, geographic and value chain boundaries of product development teams To understand the relationship of variables influencing boundary crossing behaviour of product development teams To give suggestions to better understand management of boundary crossing behaviour in product development teams A combination of qualitative and quantitative techniques was adopted to study these objectives. Based on the past literature a conceptual framework was developed. It consisted of defining the role of collaborative and interactive boundary crossing behaviours across product development teams and certain variables influencing this behaviour. The model was validated through preliminary interviews. These interviews were conducted across team members, team leaders and knowledge management experts. A few more variables were identified that were considered to influence the collaborative behaviour performed by PD teams. These variables are sharing behaviour and confidence with the time available for developing the product. The variables were operationally defined and measurement instrument, namely a questionnaire, was developed. The questionnaire was administered to team leaders and team members. The measurement instrument was tested for its psychometric properties namely, reliability and validity. Cronbach alphas are reported. For the main study, data was collected from 73 product development teams of IT organizations located in Bangalore. From the team leader the general characteristics of the PD team were understood, as well as the level of newness of the product developed. The latter was used as a measure of level of innovation. From team members, the interactive and collaborative behaviour of PD team members was studied. The statistical techniques that were used for analyzing the data are F-Test, t-test, Kruskall Wallis test, chi-square test , correlation and regression analyses. After the analysis it was found that the interactive and collaborative behaviour expressed by the teams across the three boundaries showed that as compared to collaborative behavior, product development teams more commonly used interactive behaviour. Interactive behaviours were also found to be used to the same extent across all the three boundaries. Since interactive behavior is formal and forced in organizations it is predominantly practiced although its efficiency may vary. The challenge for organizations hence is the collaborative behaviors. On the other hand, collaborative behaviour was seen used the most across horizontal boundary and the least across value chain boundary. Since the geographic distance across boundaries increases when moving from horizontal to value chain boundaries the chances of collaboration get decreased. Hence an influence of distance on boundary crossing behavior was sense influencing collaborative behaviour of product development teams. Hence further analysis focused on collaborative behaviors. The collaborative behaviour was further studied to understand its relationship with product development team behaviour, sharing behaviour of teams of outside the boundary, demographic variables and innovation level of product developed. Correlation analysis showed that the collaborative behaviour of teams were correlated with the sharing behaviour, informal groups, autonomous team leader behaviour, and open climate only. These variables were termed direct influencers of collaborative behavior.Innovation level did not play any significant role in influencing collaborative behavior.Collaboration behaviour was further studied to understand how they are causally related with these variables. Using regression analysis, the causal study considered collaboration behaviour of PD teams in general, as well as the collaboration behaviour across horizontal, geographical and value-chain boundary as the dependent variable. The independent variables studied are sharing behaviour, informal groups, open-climate behaviors, autonomous team leader behaviour. Regression results showed that open climate behaviours was causally related to overall collaboration behaviour of PD teams in all boundaries. With respect to collaboration across horizontal boundary, it was found that sharing behaviour, as well as autonomous team leader behaviour influenced them. Across geographical boundary, the open-climate was found causally related. Across value chain boundary sharing behaviour was found to influence collaborative behaviour. It was found that only some variables influence boundary crossing behavior namely, collaborative behavior, the most. These were open climate behaviors, sharing behaviour, and autonomous team leader behaviour. These were labeled direct influencers. The ones that did not show a direct influence were termed as indirect influencers. Since the role of direct influencers was clearly understood, the role of indirect influencers needed further analysis as these were variables selected from literature and expert interviews and expected to have influence on boundary crossing behaviour. Those variables that did not directly enter the regression analysis were further studied tounder stand if they had a relationship with the direct influencers independent of collaborative behaviors. It was assumed that if they did then they may indirectly influence collaborative behaviors. For this the indirect variables were correlated with the direct influencers. The results showed that open-climate was positively correlated with awareness of objectives, PD life cycle and the team’s confidence in time line of the project. Interestingly sharing behavior and autonomous behaviour of the team leader was not correlated with any potentially indirect influencer or variable. This meant that awareness of objectives, PD life cycle and the team’s confidence in time line of the project can influence collaborative behavior indirectly. In the next analysis the role of PD was understood deeper in the context of level of innovation and duration of projects vis-à-vis collaboration. This is specifically done as the poor influence of level of innovation and duration were a surprise since they were expected to have influence on boundary crossing behavior. Teams were classified into low, medium and high innovation level teams. The collaboration behaviour within these teams was then studied. The results showed that there was a pattern in the usage of collaboration behaviour across the different channels. Collaboration behaviour was used most across medium innovation level team as compared to low and high innovation level teams. This was the case of collaboration across horizontal and geographical boundary. In the case of value chain boundary, no such pattern was recognizable. Interestingly it meant that in low and high innovation collaborative behavior was lower and it increased only during medium innovation. Further to this, the influence of collaboration on duration of product developed was studied. The correlation study showed negative relation between the two only for horizontal boundaries. This meant that increase in collaborative behavior across horizontal boundaries result in lesser time taken to develop the product. The last chapter in this thesis describes the conclusions from this study and the managerial implications regarding nurturing and managing boundaries of PD teams.

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