Hydrology

DTFH61-83-C-00118This manual provides a synthesis of practical hydrologic methods and techniques to assist the highway engineer in the analysis and design of highway drainage structures. The manual begins with a discussion of descriptive hydrology, the surface runoff process and hydrologic data with emphasis given to the highway stream-crossing problem. The commonly used frequency distributions for estimating peak flows for basins with adequate data are discussed in detail and illustrated by examples. USGS regional regression equations and other methods for peak flow determinations in ungaged watersheds and in basins with insufficient data are presented with examples. Methods for developing unit hydrographs from streamflow data and by the Snyder and SCS synthetic procedures for ungaged sites are described in detail. Techniques for developing design storms and design hydrographs are given for basins with and without data. The Muskingum method for routing of hydrographs in channels and the Storage-Indication method for storage routing at highway embankments are discussed with illustrative examples. Estimates of peak flow and hydrograph development in urban watersheds using the SCS methods of TR-55 and the USGS Basin Development Factor procedure are illustrated in detail. The manual concludes with a brief discussion of risk analysis and its dependence on hydrologic analysis

Great Expectations: Voluntary Sports Clubs and Their Role in Delivering National Policy for English Sport

“The original publication is available at www.springerlink.com”. Copyright International Society for Third-Sector Research and The Johns Hopkins University. DOI: 10.1007/s11266-009-9095-yVoluntary sports clubs (VSCs) account for about a quarter of all volunteering in England. The volunteers work in a mutual aid, self-production, self-consumption system whose main purpose is identifying and nurturing high-level performers. But the new HMG/Sport England strategies leading to London 2012 expects volunteers to make a major contribution to sustaining and extending participation. The study utilized six focus group sessions with a total of 36 officials and members of 36 clubs across the six counties of Eastern England to assess whether and to what extent government policy objectives can be delivered through the voluntary sector. The study focused on the perceptions and attitudes of club members about being expected to serve public policy and the current pressures they and their clubs face. The results lead the authors to question the appropriateness, sensitivity, and feasibility of current sport policy, particularly the emphasis on VSCs as policy implementers.Peer reviewe

High School Exit Examinations: When Do Learning Effects Generalize?

This paper reviews international and domestic evidence on the effects of three types of high school exit exam systems: voluntary curriculum-based external exit exams, universal curriculum-based external exit exam systems and minimum competency tests that must be passed to receive a regular high school diploma. The nations and provinces that use Universal CBEEES (and typically teacher grades as well) to signal student achievement have significantly higher achievement levels and smaller differentials by family background than otherwise comparable jurisdictions that base high stakes decisions on voluntary college admissions tests and/or teacher grades. The introduction of Universal CBEEES in New York and North Carolina during the 1990s was associated with large increases in math achievement on NAEP tests. Research on MCTs and high school accountability tests is less conclusive because these systems are new and have only been implemented in one country. Cross-section studies using a comprehensive set of controls for family background have not found that students in MCT states score higher on audit tests like the NAEP that carry no stakes for the test taker. The analysis reported in table 1 tells us that the five states that introduced MCTs during the 1990s had significantly larger improvements on NAEP tests than states that made no change in their student accountability regime. The gains, however, are smaller than for the states introducing Universal CBEEES. New York and North Carolina. The most positive finding about MCTs is that students in MCT states earn significantly more during the first eight years after graduation than comparable students in other states suggesting that MCTs improve employer perceptions of the quality of the recent graduates of local high schools

A 'Performative' Social Movement: The Emergence of Collective Contentions within Collaborative Governance

The enmeshment of urban movements in networks of collaborative governance has been characterised as a process of co-option in which previously disruptive contentions are absorbed by regimes and reproduced in ways that do not threaten the stability of power relations. Applying a theoretical framework drawn from feminist philosopher Judith Butler this paper directs attention to the development of collective oppositional identities that remain embedded in conventional political processes. In a case study of the English tenants' movement, it investigates the potential of regulatory discourses that draw on market theories of performative voice to offer the collectivising narratives and belief in change that can generate the emotional identification of a social movement. The paper originates the concept of the ‘performative social movement’ to denote the contentious claims that continue to emerge from urban movements that otherwise appear quiescent

Breadwinners and Homemakers: Migration and Changing Conjugal Expectations in Rural Bangladesh

The literature on marriage norms and aspirations across societies largely sees the institution as static – a tool for the assertion of masculinities and subordination of women. The changing meanings of marriage and conjugality in the contemporary context of globalisation have received scant attention. Based on research in rural Bangladesh, this article questions the usefulness of notions of autonomy and dependence in understanding conjugal relations and expectations in a context of widespread migration for extended periods, especially to overseas destinations, where mutuality is crucial for social reproduction, though in clearly genderdemarcated domains

Comparing nuclear power trajectories in Germany and the UK: from ‘regimes' to ‘democracies’ in sociotechnical transitions and Discontinuities

This paper focuses on arguably the single most striking contrast in contemporary major energy politics in Europe (and even the developed world as a whole): the starkly differing civil nuclear policies of Germany and the UK. Germany is seeking entirely to phase out nuclear power by 2022. Yet the UK advocates a ‘nuclear renaissance’, promoting the most ambitious new nuclear construction programme in Western Europe.Here,this paper poses a simple yet quite fundamental question: what are the particular divergent conditions most strongly implicated in the contrasting developments in these two countries. With nuclear playing such an iconic role in historical discussions over technological continuity and transformation, answering this may assist in wider understandings of sociotechnical incumbency and discontinuity in the burgeoning field of‘sustainability transitions’. To this end, an ‘abductive’ approach is taken: deploying nine potentially relevant criteria for understanding the different directions pursued in Germany and the UK. Together constituted by 30 parameters spanning literatures related to socio-technical regimes in general as well as nuclear technology in particular, the criteria are divided into those that are ‘internal’ and ‘external’ to the ‘focal regime configuration’ of nuclear power and associated ‘challenger technologies’ like renewables. It is ‘internal’ criteria that are emphasised in conventional sociotechnical regime theory, with ‘external’ criteria relatively less well explored. Asking under each criterion whether attempted discontinuation of nuclear power would be more likely in Germany or the UK, a clear picture emerges. ‘Internal’ criteria suggest attempted nuclear discontinuation should be more likely in the UK than in Germany– the reverse of what is occurring. ‘External’ criteria are more aligned with observed dynamics –especially those relating to military nuclear commitments and broader ‘qualities of democracy’. Despite many differences of framing concerning exactly what constitutes ‘democracy’, a rich political science literature on this point is unanimous in characterising Germany more positively than the UK. Although based only on a single case,a potentially important question is nonetheless raised as to whether sociotechnical regime theory might usefully give greater attention to the general importance of various aspects of democracy in constituting conditions for significant technological discontinuities and transformations. If so, the policy implications are significant. A number of important areas are identified for future research, including the roles of diverse understandings and specific aspects of democracy and the particular relevance of military nuclear commitments– whose under-discussion in civil nuclear policy literatures raises its own questions of democratic accountability

Corrosion Susceptibility of Internally Reinforced Soil Retaining Structures

DTFH61-83-C-00010The current state of knowledge in the area of metal corrosion in reinforced soil retaining walls has been assessed. It was found that data is missing in several areas including the performance of the metal reinforcement in a highly alkaline environment as well as in the presence of high chloride concentrations. Moreover, no quantitative information was found on the effect of climatological conditions. In order to determine whether there are any corrosion problems in completed Reinforced Earth walls, four such walls were selected for study. All four walls are in relatively severe environments. It was determined that two of the above walls may have corrosion problems which could reduce their design life. It is recommended that further field studies be undertaken in order to assess the magnitude of the problems. It is further recommended that research be conducted to determine the safe limits of the reinforced earth concept

Review of post-process optical form metrology for industrial-grade metal additive manufactured parts

The scope of this review is to investigate the main post-process optical form measurement technologies available in industry today and to determine whether they are applicable to industrial-grade metal additive manufactured parts. An in-depth review of the operation of optical three-dimensional form measurement technologies applicable to metal additive manufacturing is presented, with a focus on their fundamental limitations. Looking into the future, some alternative candidate measurement technologies potentially applicable to metal additive manufacturing will be discussed, which either provide higher accuracy than currently available techniques but lack measurement volume, or inversely, which operate in the appropriate measurement volume but are not currently accurate enough to be used for industrial measurement

Energy Losses Through Junction Manholes, Volume II: Experimental Data

DTFH61-88-C-00004, DTFH61-92-C-00094The objective of this report is to develop and test methodologies for computing energy losses at junction manholes. Laboratory data obtained over a 6-year period at the Federal Highway Administration's (FHWA's) Hydraulics Laboratory are analyzed within the framework of three methodologies: the energy grade line, power loss, and neural networks. Descriptions of the methods are presented, along with a statistical analysis comparing the accuracy with which each method computes observed depth in the junction manhole. Volume I provides an overview of the hydraulic conditions at junction manholes and identifies the need to supplement existing data for development of predictive equations for computing energy losses. Also discussed are prior research results, three analytical methods for determining junction losses, and the experimental configurations in the laboratory. This report also provides a detailed analysis and performance comparison of each of the three methodologies analyzed. Guidance is given as to which methodology may be most appropriate in computing the energy losses through a pipe system. Volume II documents the physical and hydraulic data collected for each of the 739 laboratory experiments performed

Improving the professional knowledge base for education: Using knowledge management (KM) and Web 2.0 tools

Improving education systems is an elusive goal. Despite considerable investment, international studies such as the OECD Teaching and Learning International Survey (TALIS) project and the McKinsey Report How the world’s best performing schools come out on top indicate that improving teacher quality is more important than increased financial investment. Both reports challenge governments, academics and practitioners to adopt new ways of sharing and building knowledge. This paper makes the case for national education systems to adopt tried and tested knowledge management and web 2.0 tools used by other sectors and highlights the neglected potential of teacher educators as agents for improvement