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An Assessment of Performance Measures in the Transportation Development Act
"This report examines the performance measures requirements in California’s Transportation Development Act (TDA) of 1971. The TDA is an important source of funding for the state’s public transit agencies, representing approximately 18 percent of their total (2018) revenue between the TDA’s two funds (LTF and STA). Since the TDA’s passage in 1971, the transit operating environment in California has changed, in some cases dramatically. The state has nearly doubled in population (20.4 million in 1971 to 39.8 million in 2019), traffic has worsened considerably, climate change is now a central public policy focus, and many places around the state are investing heavily in making public transit a viable alternative to driving. Our research examined the TDA’s performance requirements and their effects on the state’s transit operators. We also considered alternative approaches to both transit finance and performance requirements, by studying transit funding programs in 13 other states that invest significant amounts of funding in transit. In brief, we find that the TDA’s use of performance measurements to allocate funding is unusual. The states we studied do not for the most part make funding contingent on performance, thereby avoiding the unproductive and difficult-to-implement “death penalty” (Taylor, 1995) of withholding subsidies for a much-needed public service. In several of the cases analyzed, by contrast, states guarantee specific levels or amounts of funding for transit service.To examine how the TDA’s performance measures are working, we conducted a survey of California transit professionals at agencies and at Regional Transportation Planning Agencies (RTPAs). That California’s aspirations for transit have evolved over the years is reflected in the frequent loopholes and exemptions the legislature has added to the TDA to give struggling operators more latitude to receive funding in order to meet multiple goals and objectives while staying in compliance with a single cost-effectiveness goal. The extent and frequency with which these exemptions have occurred suggests that the larger aims for public transit, and indeed the goals for the TDA program itself, have evolved, and need to be re-thought holistically, rather than incrementally.Accordingly we offer six recommendations concerning transit performance assessment in the TDA.
Hybrid Model For Word Prediction Using Naive Bayes and Latent Information
Historically, the Natural Language Processing area has been given too much
attention by many researchers. One of the main motivation beyond this interest
is related to the word prediction problem, which states that given a set words
in a sentence, one can recommend the next word. In literature, this problem is
solved by methods based on syntactic or semantic analysis. Solely, each of
these analysis cannot achieve practical results for end-user applications. For
instance, the Latent Semantic Analysis can handle semantic features of text,
but cannot suggest words considering syntactical rules. On the other hand,
there are models that treat both methods together and achieve state-of-the-art
results, e.g. Deep Learning. These models can demand high computational effort,
which can make the model infeasible for certain types of applications. With the
advance of the technology and mathematical models, it is possible to develop
faster systems with more accuracy. This work proposes a hybrid word suggestion
model, based on Naive Bayes and Latent Semantic Analysis, considering
neighbouring words around unfilled gaps. Results show that this model could
achieve 44.2% of accuracy in the MSR Sentence Completion Challenge
Designing and Operating Safe and Secure Transit Systems: Assessing Current Practices in the United States and Abroad, MTI Report 04-05
Public transit systems around the world have for decades served as a principal venue for terrorist acts. Today, transit security is widely viewed as an important public policy issue and is a high priority at most large transit systems and at smaller systems operating in large metropolitan areas. Research on transit security in the United States has mushroomed since 9/11; this study is part of that new wave of research. This study contributes to our understanding of transit security by (1) reviewing and synthesizing nearly all previously published research on transit terrorism; (2) conducting detailed case studies of transit systems in London, Madrid, New York, Paris, Tokyo, and Washington, D.C.; (3) interviewing federal officials here in the United States responsible for overseeing transit security and transit industry representatives both here and abroad to learn about efforts to coordinate and finance transit security planning; and (4) surveying 113 of the largest transit operators in the United States. Our major findings include: (1) the threat of transit terrorism is probably not universal—most major attacks in the developed world have been on the largest systems in the largest cities; (2) this asymmetry of risk does not square with fiscal politics that seek to spread security funding among many jurisdictions; (3) transit managers are struggling to balance the costs and (uncertain) benefits of increased security against the costs and (certain) benefits of attracting passengers; (4) coordination and cooperation between security and transit agencies is improving, but far from complete; (5) enlisting passengers in surveillance has benefits, but fearful passengers may stop using public transit; (6) the role of crime prevention through environmental design in security planning is waxing; and (7) given the uncertain effectiveness of antitransit terrorism efforts, the most tangible benefits of increased attention to and spending on transit security may be a reduction in transit-related person and property crimes
Contributions of temperament to buffering and sensitization processes in children’s development
ABSTRACT: Temperament refers to relatively stable, early appearing, biologically rooted individual differences in behavioral traits. Individual differences in temperament are multidetermined encompassing both biological and experiential influences. Evidence indicates that certain temperament traits, such as impulsivity, inhibition, and negative emotionality, can serve as developmental risk factors. Evidence also indicates that other temperament traits, such as flexible self-regulation, sociability, and task orientation, can serve to increase children's resilience
Evaluating megaprojects: from the “iron triangle” to network mapping
Evaluation literature has paid relatively little attention to the specific needs of evaluating large, complex industrial and infrastructure projects, often called ‘megaprojects’. The abundant megaproject governance literature, in turn, has largely focused on the so-called ‘megaproject pathologies’, i.e. the chronic budget overruns, and failure of such projects to keep to timetables and deliver the expected social and economic benefits. This article draws on these two strands of literature, identifies shortcomings, and suggests potential pathways towards an improved evaluation of megaprojects. To counterbalance the current overemphasis on relatively narrowly defined accountability as the main function of megaproject evaluation, and the narrow definition of project success in megaproject evaluation, the article argues that conceptualizing megaprojects as dynamic and evolving networks would provide a useful basis for the design of an evaluation approach better able to promote learning and to address the socio economic aspects of megaprojects. A modified version of ‘network mapping’ is suggested as a possible framework for megaproject evaluation, with the exploration of the multiple accountability relationships as a central evaluation task, designed to reconcile learning and accountability as the central evaluation functions. The article highlights the role of evaluation as an ‘emergent’ property of spontaneous megaproject ‘governing’, and explores the challenges that this poses to the role of the evaluator
Real-Time Hand Shape Classification
The problem of hand shape classification is challenging since a hand is
characterized by a large number of degrees of freedom. Numerous shape
descriptors have been proposed and applied over the years to estimate and
classify hand poses in reasonable time. In this paper we discuss our parallel
framework for real-time hand shape classification applicable in real-time
applications. We show how the number of gallery images influences the
classification accuracy and execution time of the parallel algorithm. We
present the speedup and efficiency analyses that prove the efficacy of the
parallel implementation. Noteworthy, different methods can be used at each step
of our parallel framework. Here, we combine the shape contexts with the
appearance-based techniques to enhance the robustness of the algorithm and to
increase the classification score. An extensive experimental study proves the
superiority of the proposed approach over existing state-of-the-art methods.Comment: 11 page
Looking back to see the future: building nuclear power plants in Europe
The so-called ‘nuclear renaissance’ in Europe is promulgated by the execution of two large engineering projects involving the construction of two European Pressurized Reactors (EPRs) in Flamanville, France and Olkiluoto in Finland. As both projects have faced budget overruns and delays, this paper analyses their governance and history to derive lessons useful for the construction of future projects. Analysis indicates that the reasons for these poor outcomes are: overoptimistic estimations, first-of-a-kind (FOAK) issues and undervaluation of regulation requirements. These pitfalls have the potential to impact on many other engineering construction projects and highlight fruitful areas of further research into project performance
A cross-national study of direct and indirect effects of cyberbullying on cybergrooming victimization via self-esteem
The present study reports frequency rates of cybergrooming, profiled characteristics of cybergrooming perpetrators, and examine direct and indirect associations between cyberbullying victimization, self-esteem, and cybergrooming victimization. The study sample included 2,162 adolescents between 11 and 19 years from three Western (Germany, the Netherlands, the United States) countries and one Southeast Asian country (Thailand). Across countries, 18.5% of participants reported having had contact with a cybergroomer. Western girls, as compared to boys, were at greater risk to have been contacted by a cybergroomer. No significant sex difference was found for Southeast Asian adolescents. Also, Southeast Asian adolescents reported higher rates of cybergroomer contact as compared to Western adolescents. Cybergroomers were most often males and older than victims. Both cyberbullying victimization and low self-esteem increased the probability of coming into contact with a cybergroomer, and self-esteem mediated the effects of cyberbullying victimization on cybergrooming victimization. The results are discussed in relation to practical implications and future research
First Results of Scanning Thermal Diffusivity Microscope (STDM) Measurements on Irradiated Monolithic and Dispersion Fuel
The thermal conductivity of the fuel material in a reactor before and during irradiation is a sensitive and fundamental parameter for thermal hydraulic calculations that are useds to correctly determine fuel heat fluxes and meat temperatures and to simulate performance of the fuel elements during operation. Several techniques have been developed to measure the thermal properties of fresh fuel to support these calculations, but it is crucial to also investigate the change of thermal properties during irradiation
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