813 resultados para TENDER OFFER


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Advances in safety research—trying to improve the collective understanding of motor vehicle crash causation—rests upon the pursuit of numerous lines of inquiry. The research community has focused on analytical methods development (negative binomial specifications, simultaneous equations, etc.), on better experimental designs (before-after studies, comparison sites, etc.), on improving exposure measures, and on model specification improvements (additive terms, non-linear relations, etc.). One might think of different lines of inquiry in terms of ‘low lying fruit’—areas of inquiry that might provide significant improvements in understanding crash causation. It is the contention of this research that omitted variable bias caused by the exclusion of important variables is an important line of inquiry in safety research. In particular, spatially related variables are often difficult to collect and omitted from crash models—but offer significant ability to better understand contributing factors to crashes. This study—believed to represent a unique contribution to the safety literature—develops and examines the role of a sizeable set of spatial variables in intersection crash occurrence. In addition to commonly considered traffic and geometric variables, examined spatial factors include local influences of weather, sun glare, proximity to drinking establishments, and proximity to schools. The results indicate that inclusion of these factors results in significant improvement in model explanatory power, and the results also generally agree with expectation. The research illuminates the importance of spatial variables in safety research and also the negative consequences of their omissions.

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Identification of hot spots, also known as the sites with promise, black spots, accident-prone locations, or priority investigation locations, is an important and routine activity for improving the overall safety of roadway networks. Extensive literature focuses on methods for hot spot identification (HSID). A subset of this considerable literature is dedicated to conducting performance assessments of various HSID methods. A central issue in comparing HSID methods is the development and selection of quantitative and qualitative performance measures or criteria. The authors contend that currently employed HSID assessment criteria—namely false positives and false negatives—are necessary but not sufficient, and additional criteria are needed to exploit the ordinal nature of site ranking data. With the intent to equip road safety professionals and researchers with more useful tools to compare the performances of various HSID methods and to improve the level of HSID assessments, this paper proposes four quantitative HSID evaluation tests that are, to the authors’ knowledge, new and unique. These tests evaluate different aspects of HSID method performance, including reliability of results, ranking consistency, and false identification consistency and reliability. It is intended that road safety professionals apply these different evaluation tests in addition to existing tests to compare the performances of various HSID methods, and then select the most appropriate HSID method to screen road networks to identify sites that require further analysis. This work demonstrates four new criteria using 3 years of Arizona road section accident data and four commonly applied HSID methods [accident frequency ranking, accident rate ranking, accident reduction potential, and empirical Bayes (EB)]. The EB HSID method reveals itself as the superior method in most of the evaluation tests. In contrast, identifying hot spots using accident rate rankings performs the least well among the tests. The accident frequency and accident reduction potential methods perform similarly, with slight differences explained. The authors believe that the four new evaluation tests offer insight into HSID performance heretofore unavailable to analysts and researchers.

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It is important to examine the nature of the relationships between roadway, environmental, and traffic factors and motor vehicle crashes, with the aim to improve the collective understanding of causal mechanisms involved in crashes and to better predict their occurrence. Statistical models of motor vehicle crashes are one path of inquiry often used to gain these initial insights. Recent efforts have focused on the estimation of negative binomial and Poisson regression models (and related deviants) due to their relatively good fit to crash data. Of course analysts constantly seek methods that offer greater consistency with the data generating mechanism (motor vehicle crashes in this case), provide better statistical fit, and provide insight into data structure that was previously unavailable. One such opportunity exists with some types of crash data, in particular crash-level data that are collected across roadway segments, intersections, etc. It is argued in this paper that some crash data possess hierarchical structure that has not routinely been exploited. This paper describes the application of binomial multilevel models of crash types using 548 motor vehicle crashes collected from 91 two-lane rural intersections in the state of Georgia. Crash prediction models are estimated for angle, rear-end, and sideswipe (both same direction and opposite direction) crashes. The contributions of the paper are the realization of hierarchical data structure and the application of a theoretically appealing and suitable analysis approach for multilevel data, yielding insights into intersection-related crashes by crash type.

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Understanding the expected safety performance of rural signalized intersections is critical for (a) identifying high-risk sites where the observed safety performance is substantially worse than the expected safety performance, (b) understanding influential factors associated with crashes, and (c) predicting the future performance of sites and helping plan safety-enhancing activities. These three critical activities are routinely conducted for safety management and planning purposes in jurisdictions throughout the United States and around the world. This paper aims to develop baseline expected safety performance functions of rural signalized intersections in South Korea, which to date have not yet been established or reported in the literature. Data are examined from numerous locations within South Korea for both three-legged and four-legged configurations. The safety effects of a host of operational and geometric variables on the safety performance of these sites are also examined. In addition, supplementary tables and graphs are developed for comparing the baseline safety performance of sites with various geometric and operational features. These graphs identify how various factors are associated with safety. The expected safety prediction tables offer advantages over regression prediction equations by allowing the safety manager to isolate specific features of the intersections and examine their impact on expected safety. The examination of the expected safety performance tables through illustrated examples highlights the need to correct for regression-to-the-mean effects, emphasizes the negative impacts of multicollinearity, shows why multivariate models do not translate well to accident modification factors, and illuminates the need to examine road safety carefully and methodically. Caveats are provided on the use of the safety performance prediction graphs developed in this paper.

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Purpose: To provide recommendations for construction clients who design and implement financial incentive mechanisms (FIMs) on projects. ---------- Methodology: Four large Australian building projects commissioned by government clients under managing contractor contracts and completed between 2001 and 2005 were examined to explore the ‘drivers’ that promoted motivation toward financial incentive goals. The results were triangulated across data sources, projects and stakeholder types. ---------- Findings: FIM design should incorporate: 1. flexibility to modify goals and measurement procedures over time, 2. multiple goals covering different project areas, 3. distribution of rewards across all the key organizations contributing to team performance (e.g. potentially not just the contractor, but the subcontractors and consultants) and a reward amount sufficient to be valued by potential recipients. FIM benefits are maximized through the following complementary procurement initiatives: 4. equitable contract risk allocation, 5. early contractor involvement in design, 6. value-driven tender selection, 7. relationship workshops, and 8. future work opportunities.---------- Research Limitations: This paper provides practical recommendations to industry and hence does not emphasize theoretical aspects.---------- Practical Implications: The uptake of these recommendations is likely to increase the impact of FIMs on motivation and improve project and industry outcomes. Although the study focuses on government clients of building projects, all the recommendations would seem to apply equally to private-sector clients and to non-building projects.---------- Originality: In order to improve motivation and reward high performance, clients are increasingly using FIM in their construction contracts. Despite the rising use of financial incentives, there is a lack of comprehensive construction-specific knowledge available to help clients maximize outcomes. The study addresses this gap in the literature.

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The use of appropriate financial incentives within construction projects can contribute to strong alignment of project stakeholder motivation with project goals. However, effective incentive system design can be a challenging task and takes skillful planning by client managers in the early stages of a project. In response to a lack of information currently available to construction clients in this area, this paper explores the features of a successful incentive system and identifies key learnings for client managers to consider when designing incentives. Our findings, based on data from a large Australian case study, suggest that key stakeholders place greater emphasis on the project management processes that support incentives than on the incentive itself. Further, contractors need adequate time and information to accurately estimate construction costs prior to their tender price submission to ensure cost-focused incentive goals remain achievable. Thus, client managers should be designing incentives as part of a supportive procurement strategy to maximize project stakeholder motivation and prevent goal misalignment.

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The concept of sustainable urban development has been pushed to the forefront of policy-making and politics as the world wakes up to the impacts of climate change and the effects of modern urban lifestyles. Today, sustainable development has become a very prominent element in the day-to-day debate on urban policy and the expression of that policy in urban planning and development decisions. As a result of this, during the last few years, sustainable development automation applications such as sustainable urban development decision support systems have become popular tools as they offer new opportunities for local governments to realise their sustainable development agendas. This chapter explores a range of issues associated with the application of information and communication technologies and decision support systems in the process of underpinning sustainable urban development. The chapter considers how information and communication technologies can be applied to enhance urban planning, raise environmental awareness, share decisions and improve public participation. It introduces and explores three web-based geographical information systems projects as best practice. These systems are developed as support tools to include public opinion in the urban planning and development processes, and to provide planners with comprehensive tools for the analysis of sustainable urban development variants in order to prepare the best plans for constructing sustainable urban communities and futures.

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This workshop focuses upon research about the qualities of community in music and of music in community facilitated by technologically supported relationships. Generative media systems present an opportunity for users to leverage computational systems to form new relationships through interactive and collaborative experiences. Generative music and art are a relatively new phenomenon that use procedural invention as a creative technique to produce music and visual media. Early systems have demonstrated the potential to provide access to collaborative ensemble experiences for users with little formal musical or artistic expertise. This workshop examines the relational affordances of these systems evidenced by selected field data drawn from the Network Jamming Project. These generative performance systems enable access to unique ensembles with very little musical knowledge or skill and offer the possibility of interactive relationships with artists and musical knowledge through collaborative performance. In this workshop we will focus on data that highlights how these simulated experiences might lead to understandings that may be of social benefit. Conference participants will be invited to jam in real time using virtual interfaces and to evaluate purposively selected video artifacts that demonstrate different kinds of interactive relationship with artists, peers, and community and that enrich the sense of expressive self. Theoretical insights about meaningful engagement drawn from the longitudinal and cross cultural experiences will underpin the discussion and practical presentation.

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The processes of digitization and deregulation have transformed the production, distribution and consumption of information and entertainment media over the past three decades. Today, researchers are confronted with profoundly different landscapes of domestic and personal media than the pioneers of qualitative audience research that came to form much of the conceptual basis of Cultural Studies first in Britain and North America and subsequently across all global regions. The process of media convergence, as a consequence of the dual forces of digitisation and deregulation, thus constitutes a central concept in the analysis of popular mass media. From the study of the internationalisation and globalisation of media content, changing regimes of media production, via the social shaping and communication technologies and conversely the impact of communication technology on social, cultural and political realities, to the emergence of transmedia storytelling, the interplay of intertextuality and genre and the formation of mediated social networks, convergence informs and shapes contemporary conceptual debates in the field of popular communication and beyond. However, media convergence challenges not only the conceptual canon of (popular) communication research, but poses profound methodological challenges. As boundaries between producers and consumers are increasingly fluent, formerly stable fields and categories of research such as industries, texts and audiences intersect and overlap, requiring combined and new research strategies. This preconference aims to offer a forum to present and discuss methodological innovations in the study of contemporary media and the analysis of the social, cultural,and political impact and challenges arising through media convergence. The preconference thus aims to focus on the following methodological questions and challenges: *New strategies of audience research responding to the increasing individualisation of popular media consumption. *Methods of data triangulation in and through the integrated study of media production, distribution and consumption. *Bridging the methodological and often associated conceptual gap between qualitative and quantitative research in the study of popular media. *The future of ethnographic audience and production research in light of blurring boundaries between media producers and consumers. *A critical re-examination of which textual configurations can be meaningfully described and studied as text. *Methodological innovations aimed at assessing the macro social, cultural and political impact of mediatization (including, but not limited to, "creative methods"). *Methodological responses to the globalisation of popular media and practicalities of international and transnational comparative research. *An exploration of new methods required in the study of media flow and intertextuality.

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Parallel computing is currently used in many engineering problems. However, because of limitations in curriculum design, it is not always possible to offer students specific formal teaching in this topic. Furthermore, parallel machines are still too expensive for many institutions. The latest microprocessors, such as Intel’s Pentium III and IV, embody single instruction multiple-data (SIMD) type parallel features, which makes them a viable solution for introducing parallel computing concepts to students. Final year projects have been initiated utilizing SSE (streaming SIMD extensions) features and it has been observed that students can easily learn parallel programming concepts after going through some programming exercises. They can now experiment with parallel algorithms on their own PCs at home. Keywords

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Aim. To explore and compare older home care clients’ (65+) and their professionals’ perceptions of the clients’ psychological well-being and care and to identify possible differences in these perceptions. Background. Psychological well-being is considered an important dimension of quality of life. With advancing age, older people require home care support to be able to remain in their own home. The main goal of care is to maximise their independence and quality of life. Design. Descriptive, survey design with questionnaire. Methods. A postal questionnaire was distributed to 200 older home care clients and 570 social and health care professionals in 2007. The total response rate was 63%. The questionnaire consisted of questions about clients’ psychological well-being and the provision of care by home care professionals. The differences in responses between clients and professionals were analysed using cross-tabulations, the Pearson Chi-Square Test and Fisher’s Exact Tests. Results. The professional group believed that their clients did not have plans for the future. They believed that their clients felt themselves depressed and suffering from loneliness significantly more often than the client group did. The client group were also significantly more critical of the care (motivating independent actions, physical, psychological and social care) they got from the professional group than how the professionals evaluated the care they gave. Conclusions. To be able to support older clients to continue living at home, professionals need to provide a service that meets client’s own perceptions and complex social and health care needs as well as personal sense of well-being. Relevance to clinical practice. The findings offer useful insights for the professional in planning and delivering appropriate home care services. A better understanding of differences between clients’ and professionals’ perceptions could lead to a better individualised care outcome.

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Organ printing techniques offer the potential to produce living 3D tissue constructs to repair or replace damaged or diseased human tissues and organs. Using these techniques, spatial variations along multiple axes with high geometric complexity can be obtained.. The level of control offered by these technologies to develop printed tissues will allow tissue engineers to better study factors that modulate tissue formation and function, and provide a valuable tool to study the effect of anatomy on graft performance. In this chapter we discuss the history behind substrate patterning and cell and organ printing, and the rationale for developing organ printing techniques with respect to limitations of current clinical tissue engineering strategies to effectively repair damaged tissues. We discuss current 2-dimensional and 3-dimesional strategies for assembling cells as well as the necessary support materials such as hydrogels, bioinks and natural and synthetic polymers adopted for organ printing research. Furthermore, given the current state-of-the-art in organ printing technologies, we discuss some of their limitations and provide recommendations for future developments in this rapidly growing field.

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Sustainable development has long been promoted as the best answer to the world’s environmental problems. This term has generated mass appeal as it implies that both the development of the built environment and its associated resource consumption can be achieved without jeopardising the natural environment. In the urban context, sustainability issues have been reflected in the promotion of sustainable urban development, which emphasises the sensible exploitation of scarce natural resources for urbanisation in a manner that allows future generations to repeat the process. This chapter highlights attempts to promote sustainable urban development through an integration of three important considerations: planning, development and the ecosystem. It highlights the fact that spatial planning processes were traditionally driven by economic and social objectives, and rarely involved promoting the sustainability agenda to achieve a sustainable urban future. As a result, rapid urbanisation has created a variety of pressures on the ecosystem upon which we rely. It is believed that the integration of the urban planning and development processes within the limitations of the ecosystem, monitored by a sustainability assessment mechanism, would offer a better approach to maintaining sustainable resource use without compromising urban development.

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This paper takes the position that children are at risk of being marginalised when research methods are not tailored to their requirements. In particular, children who are negotiating early adolescence are presented as an ideal group for involvement with narrative research approaches that attempt to be flexible and creative. With the premise that the need to juggle multiple realities within complex societal structures is challenging and isolating for such children, narrative methods offer a promising mode of access to their individual realities. Children's own self-narratives in the form of email journal entries are proposed as research tools that can help to minimise issues arising from resistance to adults and problems of shared vocabulary that may occur using more traditional methods. Digital journaling, as a means of capturing self-narratives, can provide a convenient space for young people to generate and share their own personal accounts of their lives and their experiences that can also serve to inform others. Guidelines are offered for how to manage a journaling project that is not reliant on children's physical presence within school settings. Digital journals are thus described as multi-function mechanisms that can support personal growth as well as promote shared understandings and social fairness between adults and children.

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Though web services offer unique opportunities for the design of new business processes, the assessment of the potential impact of Web services on existing business information systems is often reduced to technical aspects. This paper proposes a four-phase methodology which facilitates the evaluation of the potential use of Web services on business information systems both from a technical and from a strategic viewpoint. It is based on business process models, which are used to frame the adoption and deployment of Web services and to assess their impact on existing business processes. The application of this methodology is described using a procurement scenario.