717 research outputs found

    Efficient Analysis of Complex Diagrams using Constraint-Based Parsing

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    This paper describes substantial advances in the analysis (parsing) of diagrams using constraint grammars. The addition of set types to the grammar and spatial indexing of the data make it possible to efficiently parse real diagrams of substantial complexity. The system is probably the first to demonstrate efficient diagram parsing using grammars that easily be retargeted to other domains. The work assumes that the diagrams are available as a flat collection of graphics primitives: lines, polygons, circles, Bezier curves and text. This is appropriate for future electronic documents or for vectorized diagrams converted from scanned images. The classes of diagrams that we have analyzed include x,y data graphs and genetic diagrams drawn from the biological literature, as well as finite state automata diagrams (states and arcs). As an example, parsing a four-part data graph composed of 133 primitives required 35 sec using Macintosh Common Lisp on a Macintosh Quadra 700.Comment: 9 pages, Postscript, no fonts, compressed, uuencoded. Composed in MSWord 5.1a for the Mac. To appear in ICDAR '95. Other versions at ftp://ftp.ccs.neu.edu/pub/people/futrell

    Assessment of the potential costs and benefits of water trading across northern Australia<br />

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    SummaryThis report is the final of three reports and part of a two year project entitled Establishing water markets in northern Australia: a study to assess feasibility and consequences of market-based mechanisms of water delivery undertaken through the Australian National University&rsquo;s Crawford School of Economics and Government. The Tropical Rivers and Coastal Knowledge (TRaCK) hub funded this project under Theme 6.1 &ldquo;Sustainable Enterprises&rdquo;. This research is also being done in collaboration with the North Australian Indigenous Land and Sea Management Alliance (NAILSMA).This third report provides an assessment of the potential costs and benefits of water markets across northern Australia with consideration of efficiency, equity and effectiveness criteria. The region under focus is the tropical belt of northern Australia which comprises the jurisdictions of Queensland, Northern Territory and Western Australia, (with attention on the Gulf, Timor and North East drainage divisions).Water trading is at a formative stage in northern Australia, with few (if any) recorded trades at the time of writing. Markets have been effective in southern Australia in providing flexibility to irrigators and supporting productivity through reallocation during drought. Markets under the National Water Initiative (NWI) are seen as an effective tool to optimise economic, social and ecological values associated with water.There are preconditions for a water market to be effective. Important is for there to be low to medium transactions costs. A transaction cost is the costs involved in executing a trade that are above and beyond the actual price paid for the water (they can include travel time, fees, title searches and other costs). The potential for high and increased transactions costs is significant across northern Australia. A key reason for this is uncertainty over Indigenous rights and interests to water, which if not resolved could impose constraints on water markets. This suggests that there must be greater certainty around Indigenous involvement in water markets.There are environmental costs associated with water markets. Experience in the Murray Darling Basin highlights there have been environmental impacts from water trading (though it is&nbsp; acknowledged that it is difficult to separate these impacts from the effects of drought and increased development). These impacts include increased salinity, and effects from the physical&nbsp; change in the timing and location of water use. One outcome of the development of water markets in southern Australia was the activation of sleeper and dozer entitlements- this meant more water was being used. Across northern Australia most rivers are not perennial, there is a reliance on groundwater and the expansion of storages is constrained There is the potential in northern Australia for environmental impacts from trade. These impacts include: increased salinity&nbsp; in-stream; water logging from more on-farm use; saltwater intrusion because of reduced flows; and&nbsp; during the dry increased nutrient loads could threaten the health of rivers. These issues can be addressed through management efforts. For example, in the Ord, water managers have increased dry&nbsp; season flows to disperse nutrients from agricultural activity.Efficiency is key aim of water markets. Economic efficiency arises when all the gains from trade&nbsp; have been exhausted and the costs imposed on others from water use have been fully accounted for in the decision making of water users. Any assessment of efficiency of water markets, however, requires more than simply a comparison of quantified private costs and benefits. This is because, typically, water markets have been implemented only for consumptive uses of water and the effects of water use on downstream users and the environment have typically been ignored or not fully considered. Any assessment of efficiency in the north must seek to integrate customary or ecological values, but it is acknowledged that this is complex as these values are intangible and difficult to quantify.Issues of equity are important in the transition to water access rights. In the north, equity should be given increased prominence because there is a significant Indigenous population in the region who are subject to chronic socioeconomic disadvantage. In allocating property rights to water there will need to be consideration of Indigenous Australians. Including Indigenous people in&nbsp; water markets through a structure that is appropriate will offer challenges to policy makers. Quantifying the amounts of water to be provided for consumptive purposes and non consumptive purposes (such as spiritual values) is also complex. There will need to be considerable Indigenous community consultation to ensure principles of equity are upheld. Water planning should provide important parameters to ensure Indigenous customary aspirations are not threatened by water trading. There will need to be consideration of surface and groundwater connectivity, and the effect of extraction on groundwater dependent ecosystems, which are of high importance to Indigenous people in the region. These parameters should be reflected in trading rules. Ongoing Indigenous collaboration and engagement in water allocation is essential- such efforts should be underpinned by capacity development.The concept of water markets can be politically contentious. In our first work for this project, community opposition was identified as a key barrier to the development of water markets by research participants. However, it is important to emphasise that a slender majority of all respondents in our second study agreed that water markets would be useful in their region. Indigenous respondents were more likely to agree that water markets would be useful. But respondents imposed conditions on how markets should operate. Respondents placed a high value on environmental and cultural assets, and Indigenous involvement in water markets was important. It was suggested by participants that there is required more community awareness on water reform and on water markets. There is little awareness that markets can support the optimisation of environmental, economic and social values to water (which is an overarching objective of the NWI).Non market approaches may be more appropriate in some areas than markets. Markets are efficient in optimising the allocation of water where scarcity and competition exist. Markets may by themselves be incapable of achieving ecological or equity outcomes. A blend of approaches to allocating water may be more suitable. There is a growing trend in water management for increased collaboration and stakeholder driven governance approaches. Central to these approaches are inclusivity and capacity building. Collaborative efforts provide a structure for stakeholders to develop rules over allocation and management of water, as well rules for enforcement and compliance. Efforts will be required to include Indigenous interests in collaborative approaches. A key barrier in the experience of collaborative approaches in New Zealand is uncertainty around customary rights to water. Uncertainty over customary rights exists across northern Australia, and has the potential to reduce collaboration between stakeholders and constrain water planning and management efforts. Resolving Indigenous rights to water through creation of Indigenous property rights may address this uncertainty

    Analysis of institutional arrangements and constraints affecting the establishment of water markets across northern Australia<br />

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    This report is the first of three reports and part of a two year project entitled Establishing water markets in northern Australia: a study to assess feasibility and consequences of market-based&nbsp; mechanisms of water delivery undertaken through the Australian National University&rsquo;s Crawford&nbsp; School of Economics and Government. The Tropical Rivers and Coastal Knowledge (TRaCK) hub funded this project under Theme 6.1 &ldquo;Sustainable Enterprises&rdquo;. This research is being undertaken in collaboration with the North Australian Indigenous Land and Sea Management Alliance (NAILSMA). This first report provides analysis of current institutional arrangements and constraints affecting the establishment of water markets across tropical Queensland, Northern Territory and Western Australia, (with focus on the Gulf, Timor and North East drainage divisions).Research needs were identified by TRaCK and NAILSMA (and the Indigenous Water Policy Group), and from this structured interview questions were developed. Data collection involved a review of literature from a number of different sources (government, media and scholarly articles) and utilised qualitative interviews with 42 State, Territory, Commonwealth government officials, land council representatives and experts. Data was collected through structured personal interviews using an open ended format; telephone interviews were undertaken when face-to-face interviews were not possible. Most interviews were audio recorded, with transcripts sent back to all interviewees for confirmation. Findings were developed comparing multiple data sources, and sent out to interviewees for their feedback. Changes were made where appropriate and from this the final report was then produced.The research findings highlight that the jurisdictions analysed have the framework in place to support water markets, but some States have more robust frameworks in place (such as Queensland)&mdash; however, it is emphasised that the development and importance of water markets is influenced by the demand for water in each of the jurisdictions. This study found that all jurisdictions have focused on planning in the north and have taken a precautionary approach to implementing water reform. This approach has been implemented using best available knowledge, but it is informed by a recognition that generally there is a limited understanding of the characteristics of water resources across the north, as well as related ecological and cultural values. Several features are shared across jurisdictions including a desire to support Indigenous access to water that may be accommodated through an Indigenous reserve (which may include water for drinking, customary and consumptive purposes) or through an entitlement, or ablend of both. Including Indigenous people in water planning has been hampered by community capacity in the north and relevant governments are constrained in overcoming this challenge by limited resources. A key finding of the study is that inter-basin transfers are not, in general, supported by interviewees and, at present, cross border trading is highly circumscribed. Some concern was also raised about inclusion of mining activities in water markets.Various constraints were identified to the establishment of water markets across northern Australia. The key constraints identified generally across the north include physical limits to trade, knowledge gaps and legislative and institutional frameworks. In the Northern Territory, interviewees identified community attitude and values as being a major limitation on the establishment of water markets. In Queensland, the Wild Rivers Act 2005 which prescribes the intensity of water-based development in the north was viewed as a significant barrier to water trading. In Western Australia, land tenure issues, particularly native title processes were seen as being the most significant limitation (albeit indirect) to the establishment of water markets in the north. Despite these constraints, many respondents recognised that establishing a robust and cost effective water management framework has the potential to support sustainable development outcomes across the north

    Stakeholder values and attitudes towards water markets across northern Australia<br />

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    SummaryThis report is the second of three reports and part of a two year project entitled Establishing water markets in northern Australia: a study to assess feasibility and consequences of market-based mechanisms of water delivery undertaken through the Australian National University&rsquo;s Crawford School of Economics and Government. The Tropical Rivers and Coastal Knowledge (TRaCK) hub funded this project under Theme 6.1 &ldquo;Sustainable Enterprises&rdquo;. This research is also being done in collaboration with the North Australian Indigenous Land and Sea Management Alliance (NAILSMA). This second report provides analysis of stakeholder attitudes and values and their implications for the design of water markets across tropical Queensland, Northern Territory and Western Australia, (with focus on the Gulf, Timor and North East drainage divisions). The study utilised a mixed qualitative and quantitative approach, employing a survey with closed ended (5 point Likert scales and multiple choice) and open ended measures.In Task 2 we surveyed 120 people from government, Indigenous, industry and recreational user groups and present a range of values and attitudes related to markets and we discuss the general implications for market design in the north. Analysing data from open ended measures involved coding and grouping data into categories, then identifying patterns and themes. While statistical analysis involved ordered probit models, using robust standard errors and also controlling for lack of independence within each group using cluster. Preliminary findings were sent out to respondents for their feedback and where appropriate changes made. From this the final report was produced.Our findings highlight that sustainability; environmental protection; social justice and equity; and economic development were important values to respondents in relation to water markets. Respondents emphasised the importance of robust water planning frameworks that support ecological values and irrigator and Indigenous livelihoods, and respondents overwhelmingly disagreed with the trade of environmental and cultural flows. There was also significant support for the preservation of certain catchments and aquifers for their unique values (particularly among Indigenous respondents). Social justice and equity were important to respondents, with a sentiment to include Indigenous people in water reform and in water markets. Indigenous respondents felt that current arrangements were not equitable. As well, respondents from government, Indigenous and recreational groups felt that consultation and water policy fail to adequately address the needs and interests&nbsp; of Indigenous Australians. Indigenous respondents showed support for water markets, the development of water based enterprise (such as agriculture and horticulture) and believe strongly that the benefits of water trading will be significant. These views were tempered by some concerns that&nbsp; Indigenous people may be alienated from markets and that the ecological impacts from markets could be significant.Respondents felt that water management was sustainable in their region, but at the same time they did not believe water management to be efficient. This may be related to perceptions that certain systems are not over-allocated to consumptive users. A little over half of respondents agreed that water markets help sustainable water management and that water should be a tradable commodity, and respondents that were male and had a higher education were more likely to agree to these statements. Support for separating land and water title (unbundling) was mixed, with Indigenous respondents less likely to agree to a separation. There is a level of understanding of water management in their jurisdictions were more likely to agree to water transfers. There was unanimous support for government involvement in water markets, with overwhelming support for government as regulator.Literature highlights that importance of integrating values and attitudes in resource management frameworks. We identify four general implications for the design of water markets from our findings. The first is that Indigenous involvement in water markets and reform is important as one way to address Indigenous disadvantage and to support Indigenous livelihoods. This involvement could range from water management and planning, to the recognition of customary and commercial rights. Second, respondents thought that the general community should have greater involvement in water management and planning. This would require education programs to improve awareness of reform and increased support for stakeholder input into reform, particularly where language barriers and cultural differences exist. Third, given the importance of sustainability and environmental protection, it is recommended that markets develop within a planning framework, with robust but simple trading rules to protect ecological and customary values. Fourth it was emphasised by some respondents that there should be minimal red tape and costs associated with markets given the marginal operating conditions for producers across the north.Further research could build on this exploratory work to improve understanding of how to involve Indigenous interests in water markets, and examine the attitudes and values of a broader range of stakeholders across the north (such as examining women&rsquo;s attitudes and values to water markets across the north)

    Secure Geographic Routing in Ad Hoc and Wireless Sensor Networks

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    Security in sensor networks is one of the most relevant research topics in resource constrained wireless devices and networks. Several attacks can be suffered in ad hoc and wireless sensor networks (WSN), which are highly susceptible to attacks, due to the limited resources of the nodes. In this paper, we propose innovative and lightweight localization techniques that allow for intrusion identification and isolation schemes and provide accurate location information. This information is used by our routing protocol which additionally incorporates a distributed trust model to prevent several routing attacks to the network. We finally evaluate our algorithms for accurate localization and for secure routing which have been implemented and tested in real ad hoc and wireless sensor networks

    Death of the Author 3

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    Mejora de sensores vítreos sol-gel para la conservación preventiva de materiales históricos frente a la acidez

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    [ES] Los sensores a base de recubrimientos vítreos sol-gel dopados con ácido 2[4-(dimetil-amino) fenilazo] benzoico son capaces de cambiar su absorción óptica cuando se someten a distintas concentraciones de iones H3O+ y OH-. La respuesta de los sensores en ensayos de campo se estudió en Cracovia (Polonia) variando el procedimiento normal de uso, con el fin de mejorar su respuesta. Se midieron tanto los parámetros ópticos de los sensores como las condiciones ambientales (temperatura, humedad, presión y concentraciones de SO2 y de NOx). La respuesta de los sensores se analizó en términos de los cambios de su absorción visible. Dichos cambios se deben a reacciones locales de neutralización que tienen lugar en la superficie de los sensores, debido al efecto conjunto de los contaminantes de carácter ácido y a la humedad ambiental. Se establecieron correlaciones entre la concentración del contaminante principal (SO2) y la respuesta de los sensores para elaborar una calibración directa entre la absorción óptica y el pH ambiental. Los sensores pueden detectar y evaluar la acidez ambiental, así como alertar sobre la concentración de contaminantes ácidos que pueden dañar a la mayoría de los materiales históricos.[EN] Sensors based on sol-gel glassy coatings doped with 2[4-(dimethyl-amino) phenylazo] benzoic acid are able to change their optical absorption when they are submitted to different concentration of H3O+ and OH-. The sensors behaviour in field tests was studied in Cracow (Poland), varying the normal procedure of operation to improve their response. Both the sensors optical parameters and the environmental conditions (temperature, humidity, pressure, SO2 and NOx concentrations) were measured. The sensors response was analysed in terms of their visible absorbance changes, which are due to local neutralisation reactions in the sensors surface by the join effect of acid pollutants and humidity. Correlations between the main acid pollutant (SO2) concentration and the sensors response are established to provide a relation between the optical absorption and the environmental pH. The sensors are able to detect and monitorise environmental acidity, as well as to alert on the pollutant concentration that may damage most of the historical materials.The authors wish to acknowledge bilateral Polish-Spanish project Ref. PAN-CSIC 2003PL0011, European Marie Curie project Ref. MERG-CT-2004-516436 and Spanish project Ref. CICYT-MAT-2003-03231 for financing support. N.C. acknowledges CSIC-ESF for an I3P postdoctoral contract.Peer reviewe
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