292 research outputs found

    Investigation of the potentialities of photochemical laser systems. Part I - Survey and analysis Final report, 1 Feb. 1966 - 31 Jan. 1967

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    Photodissociative laser systems used to convert solar radiation to monochromatic coherent emission - excitation mechanisms, spectroscopy of gases absorbing light, and chemical processe

    Optical-to-optical interface device

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    An investigation was conducted to develop an optical-to-optical interface device capable of performing real-time incoherent-to-incoherent optical image conversion. The photoactivated liquid crystal light valve developed earlier represented a prototype liquid crystal light valve device capable of performing these functions. A device was developed which had high performance and extended lifetime

    Investigation of the potentialities of photochemical laser systems. Part 2 - Preliminary experimental studies Final report, 1 Feb. 1966 - 31 Jan. 1967

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    Potential of photodissociative laser system for converting solar radiation to monochromatic coherent emissio

    Metropolitan Centers: Evaluating Local Implementation of Regional Plans and Policies

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    The Denver and Salt Lake City Metropolitan Planning Organizations (MPOs) have embarked upon regional visioning strategies that promote development around higher density, mixed use centers with current or future access to transit. This study examines the programs and policies in the Salt Lake City and Denver regions to examine regional vision influence on local planning and the opportunities and constraints facing centers. The research team analyzed local plans over the past several decades, interviewed planners, and examined demographic, land use and transportation characteristics in select centers across the region. We found that the regional vision had a moderate influence on local planning, due to vague definitions and criteria. However, light rail investment and market forces have had a more substantial influence—resulting in cities developing supportive transit oriented development policies. While over 100 centers have been designated, many face significant challenges to support regional goals, particularly because many light rail lines were located along rail and freeway alignments. A limited number of “tipping point centers” already contain the necessary elements to be successful with city and private investment. Many “greenfield centers” offer significant future opportunity for development, but their suburban location and infrastructure needs present significant costs and challenges. Many other “redevelopment centers” are dominated by industrial, commercial or office development, and the land use and transportation patterns within these centers present substantial hurdles that may limit their potential to achieve regional goals

    Regional Transportation and Land Use Decision Making in Metropolitan Regions: Findings from Four Case Studies

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    Throughout the United States, metropolitan regions face increasingly complex issues related to transportation and land use. The diffuse nature of decision making creates a need to better coordinate land use and transportation to address issues such as: congestion, infrastructure costs, and greenhouse gas emissions. Key players in this decision making are regional metropolitan planning organizations (MPOs) with transportation planning authority, regional planning responsibilities, and in some cases regional land use planning authority. The goal of this study was to describe and assess efforts by regional agencies to coordinate land use and transportation. Policies and processes in four key topic areas were examined: 1) Governance: formal and informal decision making approaches; 2) Coordination: strategies used to coordinate land use and transportation; 3) Growth Centers: policies to encourage development in higher density centers; and 4) Transportation Improvement Program (TIP): policies to incorporate smart growth criteria in TIP funding decisions

    Ordering of droplets and light scattering in polymer dispersed liquid crystal films

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    We study the effects of droplet ordering in initial optical transmittance through polymer dispersed liquid crystal (PDLC) films prepared in the presence of an electrical field. The experimental data are interpreted by using a theoretical approach to light scattering in PDLC films that explicitly relates optical transmittance and the order parameters characterizing both the orientational structures inside bipolar droplets and orientational distribution of the droplets. The theory relies on the Rayleigh-Gans approximation and uses the Percus-Yevick approximation to take into account the effects due to droplet positional correlations.Comment: revtex4, 18 pages, 8 figure

    Modelling to bridge many boundaries: the Colorado and Murray-Darling River basins

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    Increasing pressure on shared water resources has often been a driver for the development and utilisation of water resource models (WRMs) to inform planning and management decisions. With an increasing emphasis on regional decision-making among competing actors as opposed to top-down and authoritative directives, the need for integrated knowledge and water diplomacy efforts across federal and international rivers provides a test bed for the ability of WRMs to operate within complex historical, social, environmental, institutional and political contexts. This paper draws on theories of sustainability science to examine the role of WRMs to inform transboundary water resource governance in large river basins. We survey designers and users of WRMs in the Colorado River Basin in North America and the Murray-Darling Basin in southeastern Australia. Water governance in such federal rivers challenges inter-governmental and multi-level coordination and we explore these dynamics through the application of WRMs. The development pathways of WRMs are found to influence their uptake and acceptance as decision support tools. Furthermore, we find evidence that WRMs are used as boundary objects and perform the functions of ‘boundary work’ between scientists, decision-makers and stakeholders in the midst of regional environmental changes

    Sustainable Forest Management Preferences of Interest Groups in Three Regions with Different Levels of Industrial Forestry: An Exploratory Attribute-Based Choice Experiment

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    The challenge of sustainable forest management is to integrate diverse and sometimes conflicting management objectives. In order to achieve this goal, we need a better understanding of the aspects influencing the preferences of diverse groups and how these groups make trade-offs between different attributes of SFM. We compare the SFM preferences of interest groups in regions with different forest use histories based on the reasoning that the condition of the forest reflects the forest use history of the area. The condition of the forest also shapes an individual’s forest values and attitudes. These held values and attitudes are thought to influence SFM preferences. We tested whether the SFM preferences vary amongst the different interest groups within and across regions. We collected data from 252 persons using a choice experiment approach, where participants chose multiple times among different options described by a combination of attributes that are assigned different levels. The novelty of our approach was the use of choice experiments in the assessment of regional preference differences. Given the complexity of interregional comparison and the small sample size, this was an exploratory study based on a purposive rather than random sample. Nevertheless, our results suggest that the aggregation of preferences of all individuals within a region does not reveal all information necessary for forest management planning since opposing viewpoints could cancel each other out and lead to an interpretation that does not reflect possibly polarised views. Although based on a small\ud sample size, the preferences of interest groups within a region are generally statistically significantly different from each other; however preferences of interest groups across regions are also significantly different. This illustrates the potential importance of assessing heterogeneity by region and by group

    Online Stakeholder Interactions in the Early Stage of a Megaproject

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    The purpose of this paper is to examine the network structure of online stakeholder discussions in the planning stage of a UK public mega project, High Speed Rail. By providing new rail connections between London, Birmingham and Manchester, this project is highly complex as it is embedded in a network of stakeholder relationships that may support or oppose the project. Data drawn from Twitter was analyzed using Social Network Analysis and inductive analysis of user profiles and content. Findings indicate that the majority of online stakeholders oppose the project and form stable clusters. Larger clusters within this network may attempt to deploy power directly in the form of a manipulation strategy while smaller clusters may seek to ally themselves with more powerful groups, a pathway strategy. Overall, the methodology is a useful complement to existing methods and may provide real time insights into the complex, evolving discussions around mega projects
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