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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.
51

Performance Measurement in Small Texas Metropolitan Planning Organizations

Moore, Devin 1984- 14 March 2013 (has links)
Performance measurement has grown in importance within transportation agencies due to decreased and stipulated funding and federal focus on system performance. A shift has occurred in how transportation planning and decision making historically took place including a rise in prominence of the Metropolitan Planning Organization (MPO). The public, state and local agencies, and other stakeholders are mutually served by the regional MPO to assure that transportation funding allocation and project selection meet the regional needs and coordinate the transportation planning process to provide a seamless transportation system. The recent Federal transportation funding program MAP-21 establishes performance measures for each MPO in coordination with the State department of transportation (DOT). Small MPOs, those which serve populations of less than 200,000 people, differ vastly from larger MPOs in the amount of funds available and authority to allocate funds as well as the resources that are available to perform a performance measurement program. Small MPOs often lack the resources to identify and use performance measures, even though performance measurement at the MPO level has promoted efficient decision-making in large MPOs. This research strives to find by interviews and surveys of the small Texas MPOs if the use of certain performance measures in small MPOs can be financially upheld with limited resources and budget. This thesis is timely in relation to the MAP-21 performance measurement requirements as it shows that performance measurement is, at this time, difficult to impossible based on small Texas MPOs’ very limited resources. Due to the estimated costs of basic performance measurement programs and the difficulty in quantifying the tangible benefits, the use of performance measurements in small Texas MPOs is unlikely. Small Texas MPOs listed potential performance measurement program benefits such as: project prioritization, funding allocation, and showing the public that professional planning is useful. It was found that any potential benefits of performance measurements are limited when dealing with small communities with fairly obvious transportation problems. The estimated cost of a basic performance measurement program in a small Texas MPO was determined to be around $150,000 per year. This cost exceeded both their abilities to fund a performance measurement program and the perceived benefits of such an effort. This research suggests the following performance measures are most likely to be beneficial when proven cost effective: V/C ratios, travel times, crash rates (safety) and VMT. These measures are often easily accessible and could be beneficial in the long-range planning of a local transportation system. However, fiscal and staffing limitations, along with realities of planning for a small community make the use of performance measures difficult. The results of this study can aid the Secretary of Transportation in understanding the limited technical capacities of small Texas MPOs in regards to performance measurement.
52

Assessing Safety Performance of Transportation Systems using Microscopic Simulation

Cunto, Flávio January 2008 (has links)
Transportation safety has been recognized as a public health issue worldwide, consequently, transportation researchers and practitioners have been attempting to provide adequate safety performance for the various transportation components and facilities to all road users given the usually scarce resources available. Safety engineers have been trying to make decisions affecting safety based on the knowledge extracted from different types of statistical models and/or observational before-after analysis. It is generally recognized that this type of factual knowledge is not easily obtained either statistically or empirically. Despite the intuitive link between road safety and observed crashes, a good understanding of the sequence of events prior to the crash can provide a more rational basis for the development of engineering countermeasures. The development of more comprehensive mechanistic models for safety assessment is heavily dependent on detailed vehicle tracking data that is not readily available. The potential of microscopic simulation in traffic safety and traffic conflict analysis has gained increasing interest mostly due to recent developments in human behaviour modelling and real-time vehicle data acquisition. In this thesis, we present a systematic investigation of the use of existing behavioural microscopic simulation models in short-term road safety studies. Initially, a microscopic framework is introduced to identify potentially unsafe vehicle interactions for different vehicle movements based on three types of traffic behaviour protocols: car-following, lane change and gap acceptance. This microscopic model for safety assessment applies a safety performance measure based on pairwise comparisons of spacing and speed differential between adjacent vehicles and individual braking power in real-time. A calibration/validation procedure using factorial analysis is presented to select best model input parameters for this safety performance measure by using high resolution vehicle tracking data. The ability of the proposed safety performance measure to reflect real-life observed high-risk vehicular interactions is explored in three intuitive tests using observed crash data. Finally, the usefulness of the model is illustrated through its application to investigate the safety implications of two different geometric and operational traffic strategies. The overall results indicate that, notwithstanding the fact that actual behavioural microscopic algorithms have not been developed strictly to model crashes, they are able to replicate several factors directly related to high risk situations that could lead to crashes with reasonable accuracy. With the existing upward trend in computing power, modelling techniques and increasing availability of detailed vehicle tracking data, it is likely that safety studies will be carried out using a more mechanistic and inclusive approach based on disruptive driving behaviour rather than ultimate unpredictable and heavily restrictive crash events.
53

UTVÄRDERING AV HÖFTLEDSARTROSKOPI FÖR PATIENTER MED FEMUROACETABULÄRT INKLÄMNINGSSYNDROM : Samband mellan självskattning och fysisk prestationsförmåga

Baranowska, Marta January 2013 (has links)
No description available.
54

A Note on the Performance of the "Ahrens Algorithm"

Hörmann, Wolfgang January 2001 (has links) (PDF)
This short note discusses performance bounds for "Ahrens" algorithm, that can generate random variates from continuous distributions with monotonically decreasing density. This rejection algorithms uses constant hat-functions and constant squeezes over many small intervals. The choice of these intervals is important. Ahrens has demonstrated that the equal area rule that uses strips of constant area leads to a very simple algorithm. We present bounds on the rejection constant of this algorithm depending only on the number of intervals. (author's abstract) / Series: Preprint Series / Department of Applied Statistics and Data Processing
55

Assessing Safety Performance of Transportation Systems using Microscopic Simulation

Cunto, Flávio January 2008 (has links)
Transportation safety has been recognized as a public health issue worldwide, consequently, transportation researchers and practitioners have been attempting to provide adequate safety performance for the various transportation components and facilities to all road users given the usually scarce resources available. Safety engineers have been trying to make decisions affecting safety based on the knowledge extracted from different types of statistical models and/or observational before-after analysis. It is generally recognized that this type of factual knowledge is not easily obtained either statistically or empirically. Despite the intuitive link between road safety and observed crashes, a good understanding of the sequence of events prior to the crash can provide a more rational basis for the development of engineering countermeasures. The development of more comprehensive mechanistic models for safety assessment is heavily dependent on detailed vehicle tracking data that is not readily available. The potential of microscopic simulation in traffic safety and traffic conflict analysis has gained increasing interest mostly due to recent developments in human behaviour modelling and real-time vehicle data acquisition. In this thesis, we present a systematic investigation of the use of existing behavioural microscopic simulation models in short-term road safety studies. Initially, a microscopic framework is introduced to identify potentially unsafe vehicle interactions for different vehicle movements based on three types of traffic behaviour protocols: car-following, lane change and gap acceptance. This microscopic model for safety assessment applies a safety performance measure based on pairwise comparisons of spacing and speed differential between adjacent vehicles and individual braking power in real-time. A calibration/validation procedure using factorial analysis is presented to select best model input parameters for this safety performance measure by using high resolution vehicle tracking data. The ability of the proposed safety performance measure to reflect real-life observed high-risk vehicular interactions is explored in three intuitive tests using observed crash data. Finally, the usefulness of the model is illustrated through its application to investigate the safety implications of two different geometric and operational traffic strategies. The overall results indicate that, notwithstanding the fact that actual behavioural microscopic algorithms have not been developed strictly to model crashes, they are able to replicate several factors directly related to high risk situations that could lead to crashes with reasonable accuracy. With the existing upward trend in computing power, modelling techniques and increasing availability of detailed vehicle tracking data, it is likely that safety studies will be carried out using a more mechanistic and inclusive approach based on disruptive driving behaviour rather than ultimate unpredictable and heavily restrictive crash events.
56

Effect of carbohydrate ingestion during exercise on performance measures of wheelchair athletes

Hynes, Heather 23 September 2009 (has links)
The primary purpose of this study was to determine the effect of ingesting an 8% carbohydrate (CHO) beverage during a moderate intensity exercise trial on performance outcomes, fuel utilization and blood glucose levels of wheelchair athletes (spinal cord injury (SC I) or cerebral palsy (CP)). The secondary purpose was to analyze the dietary intake of the eight participants and to determine if they were meeting current sport nutrition guidelines for macronutrients and fluids recommended in the joint position statement developed by the American Dietetic Association (ADA), the American College of Sports Medicine (ACSM) and Dietitians of Canada (DC).<p> Under random, double blind conditions eight athletes (6 males, 2 females); mean age 36 ± 8.5 y with a SCI (n = 7) or CP (n = 1) completed two exercise trials on an adapted stationary hand cycle; each trial was 60 minutes in duration at 65 % VO2peak followed immediately by a 30-minute performance trial. During the first 60-minutes the participants were given four 200 ml dosages (15, 30, 45, 60-min) of an 8% CHO beverage or a taste-matched placebo beverage. Blood lactate and glucose levels were sampled during the 60-minute exercise trial (pre, 20, 40, 60-min) and immediately after the 30-minute performance trial (post, 2, 5, 10-min). Heart rate was monitored continuously during the exercise and performance trial. Expired gas samples were also taken for 5-min periods during the exercise trial and then continuously during the performance trial. These values were used to calculate respiratory exchange ratio (RER) and carbohydrate oxidation. Dietary intake was assessed with a three day food record.<p> No significant differences were apparent between beverage trials for total distance (km), average speed (kmhr-1) or maximum speed achieved (kmhr-1). Significant differences were evident for blood glucose values, RER and CHO oxidation between the two beverage trials (p< .05). At the end of the 30-minute performance trial blood glucose values were significantly higher in the CHO trial (4.8 ± 1.3 mmol.l-1 vs. 4.0 ± 0.5 mmol.l-1 for placebo trial; p< .05). The CHO beverage resulted in higher CHO oxidation during the last 5 minutes of the performance trial, 2.1 ± 1.0 gmin-1 vs. the placebo beverage 1.9 ± 1.0 gmin-1 (p< .05). The CHO beverage trial resulted in significantly higher RER values during the final 5 minutes of the exercise trial and during the final 10 minutes of the performance trial. At the 20-25 minute mark RER values were significantly higher with the CHO beverage trial (1.04 ± 0.10) vs. the placebo trial (1.01 ± 0.11) (p< .05). During the final 5 minutes of the performance trial RER values were also significantly higher with the CHO beverage trial (1.06 ± 0.11) vs. the placebo trial (1.01 ± 0.10) (p< .05). The results indicated the participants were not meeting the current dietary guidelines for able-bodied athletes and active adults. Only 25% of the participants met the daily caloric requirements for active adults. Carbohydrate recommendations of 6 to 10 gkg-1 body weightd -1 were not met by any of the wheelchair athletes Seven participants were within the acceptable macronutrient range (AMDR) for CHO. For protein intake, 63% of the participants were meeting the protein recommendations active adults and all of them were within the AMDR. Average caloric intake from fat exceeded current recommendations of 20 to 25%; two participants were above the AMDR. The results demonstrate that the 8% CHO beverage consumed during exercise resulted in higher CHO oxidation rates and elevated blood glucose values, but it did not result in a performance gain.
57

Balanced Scorecard utifrån ett hållbarhetsperspektiv : En studie av statliga företags hållbarhetsrapporter och dess möjlighet till integrering med ett Balanced Scorecard

Lennermark, David, Ziaei, Anahita January 2011 (has links)
Today, companies work with issues concerning Corporate Social Responsibility (CSR). A higher demand from customers and other stakeholders as well as an extended legislation are great reasons. Framework and guidelines for sustainability reporting has been developed which includes indices that companies are able to report. Though, for a long term work with sustainability a functional system and internal tool is necessary. Balanced Scorecard, BSC, is a useful tool and efforts have been made to integrate BSC and CSR with purpose to establish the work with sustainability in a more concrete and clear way. Some Greek researchers have developed a framework and their result leads to the question whether it is transferable to Swedish companies in a Swedish environment? / Företag arbetar idag med frågor som handlar om ett miljömässigt, ett ekonomiskt samt ett socialt ansvarstagande (CSR). Kunder, andra intressenter samt en utökad lagstiftning kräver det. Ramverk samt riktlinjer för hållbarhetsredovisning har utvecklats vilka inkluderar indikatorer som företag kan redovisa. För ett långsiktigt hållbarhetsarbete behövs dock ett fungerande system och ett internt verktyg. Balanced Scorecard, BSC, är ett användbart verktyg och försök har gjorts att integrera BSC och CSR med avsikt att förankra hållbarhetsarbetet på ett mer konkret och tydligt sätt i verksamheten. Några grekiska forskare har utvecklat ett ramverk och deras resultat leder fram till en fundering huruvida det är överförbart till svenska företag och svensk miljö?
58

Impact of Culture on Incentive Systems : Findings from Swedish Organizations Operating in Japan and Korea

Franzén, Andreas, Rogulla, Linus January 2011 (has links)
Many organizations use global incentive systems without recognizing the suitability to foreign subsidiaries' local cultures. Applying incentives to employees in foreign subsidiaries without considering culture's impact on incentive system effectiveness may dilute the incentives' effectiveness. The majority of the incentive system literature is based on Anglo-Saxon notions of incentive system effectiveness and employee motivation. And assuming that culture impacts incentive system effectiveness, the Anglo-Saxon notions may be inapplicable in a non-Anglo-Saxon context. This study uses a sequential exploratory mixed method to explore culture's impact on incentive systems, and to analyze the applicability of Anglo-Saxon incentive system literature to non-Anglo-Saxon cultures. The study develops a five-dimensional incentive system framework that, together with a literature review of Swedish, Japanese, and South Korean culture, interprets empirical findings. Empirical findings from Swedish organizations operating in Japan and South Korea are used to form hypotheses and a basis for qualitative interviews with representatives from the Japanese and South Korean subsidiaries. Sweden, Japan, and South Korea are strongly represented on the global market with multinational organizations covering a wide range of industries. Together they constitute a large portion of global business, and are good representatives for business in Europe and Asia. The study's results establish that culture should be considered an important determinant of incentive system effectiveness, and that the Anglo-Saxon literature may be too insular to be applied outside Anglo-Saxon countries.
59

Variance Estimation in Steady-State Simulation, Selecting the Best System, and Determining a Set of Feasible Systems via Simulation

Batur, Demet 11 April 2006 (has links)
In this thesis, we first present a variance estimation technique based on the standardized time series methodology for steady-state simulations. The proposed variance estimator has competitive bias and variance compared to the existing estimators in the literature. We also present the technique of rebatching to further reduce the bias and variance of our variance estimator. Second, we present two fully sequential indifference-zone procedures to select the best system from a number of competing simulated systems when best is defined by the maximum or minimum expected performance. These two procedures have parabola shaped continuation regions rather than the triangular continuation regions employed in several papers. The rocedures we present accommodate unequal and unknown ariances across systems and the use of common random numbers. However, we assume that basic observations are independent and identically normally distributed. Finally, we present procedures for finding a set of feasible or near-feasible systems among a finite number of simulated systems in the presence of multiple stochastic constraints, especially when the number of systems or constraints is large.
60

Revised process for work zone decision-making based on quantitative performance measures

Hartmann, Thomas Wayne 10 October 2008 (has links)
Work zones create one of the most challenging environments for drivers. Implementing work zones on urban freeways creates many issues, especially with respect to mobility. Decisions made regarding the work zone should be informed by quantitative data, collected in work zones, to ensure that the mobility impacts of the work zone treatments implemented are mitigated. A new decision-making process, which addresses the shortcomings in the current decision-making processes, was developed through the course of this research. The new process incorporates a Performance Measure/Treatment matrix, which recommends multiple performance measures, each of which is chosen to measure the mobility impacts particular to a specific work zone implementation. Most importantly, the revised decision-making process incorporates a feedback loop. Quantitative data collected in work zones is analyzed after the work zone is complete, to determine the impacts specific decisions had on mobility in the work zone. The lessons learned in previous work zones are then incorporated into the decision-making process, lessening the mobility impacts of future work zones. This thesis develops the new decision-making process, and examines the issues with the application of the process.

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