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For many image classification tasks, color histogram is usually employed as an important “signature” to describe the color
distribution of the image and infer the image content. However, most traditional color histograms cannot achieve satisfactory
results in many image classification systems. In order to improve the accuracy and reduce the computational complexity of
the classification task, an information-based color feature representation is proposed in this paper. The mutual information
between the feature and the class label is adopted to evaluate the discriminative power of the feature. A novel quantization
scheme is presented, which removes the redundant color components and combines the adjacent components together to generate
a new feature to maximize the discriminative ability. An iterative algorithm is performed to derive the color space quantization
and color feature generation. In order to illustrate the effectiveness of the proposed color representation, a specific image
classification task, i.e., differentiating the adult images from benign ones, is employed. Experimental results show that
our color feature achieves better classification performance and better efficiency compared with the traditional color histogram. 相似文献
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Aileen P. Maypa Alan T. White Elline Caňares Raffy Martinez Rose Liza Eisma-Osorio Porfirio Aliňo 《Coastal management》2013,41(5):510-524
Quantifying progress in management of marine protected areas (MPAs) is crucial to marine conservation and fisheries management in the Philippines. This study compiles data on the status, occurrence, and management gaps of MPAs through coordination with multiple organizations supporting and guiding MPAs in the Philippines. MPA management effectiveness was measured using a MPA Rating System. Since 2002 the modal MPA rating levels increased from level 1 (initiated) to level 4 (sustained) in 2008/9. This upward trend is attributed to factors that promoted both the establishment and improved management of MPAs. Analysis indicated that: (1) most MPAs struggle with budgetary constraints or lack of sustainable financing and (2) overall the MPAs are being maintained and progressing with notable improvement in management despite a range of difficulties encountered during the implementation process. For MPAs in the Visayan Region for which biophysical data were available, the MPA Rating System was used to assess the effectiveness of local government capacity building on MPA coral reef health. Our results suggest that MPAs with higher ratings are likely to have better reef health conditions. 相似文献
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Recreation: Marine Promise, Proceedings of the National Conference on Marine Recreation Susan H. Andersen, Ed., October 2–4, 1975, Newport Beach, California Parable Beach: A Primer in Coastal Zone Economics by J. W. Devanney III, G. Ashe, and B. Parkhurst, The MIT Press, 1976, 99 pp. Marine Recreational Fisheries, Proceedings of the First Annual Marine Recreational Fisheries Symposium Henry Clepper, ed., New Orleans, Louisiana, February 27, 1976. 相似文献
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Since the economic reforms in the late 1970s, the shipbuilding industry in China has enjoyed rapid growth. Over the past two decades, many new building contracts have been won and successfully completed. However, some shipyards have also suffered great losses. Basing on their experience in Southern China, the authors examine some of the major challenges that Chinese shipbuilders faced during this transitional period, when the industry ventured into the international market. These challenges are broadly categorized into two areas: (i) external factors, such as inflation and infrastructural support that the shipbuilder had no control over, and (ii) shipbuilding management, which the shipbuilder had to master in order to gain competitive advantage. Suggestions on how these problems could be tackled are discussed. 相似文献
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David A. Evans H. Spencer Banzhaf Dallas Burtraw Alan J. Krupnick Juha Siikam?ki 《Transportation》1994,21(2):229-230
Contributors to this issue 相似文献
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Transportation planning has for too long been unbalanced in that an excessive amount of time has been spent on building increasingly complex quantitative models at the expense of rather important aspects of the design and forecasting stages of the process. This paper therefore sets out to consider two related problems: that of forming a coherent and useful link between the design and evaluation stages and that of suggesting a method of dealing with probabilistic forecasts within the evaluation model.The solutions to both of these problems are linked. It is suggested that the structure of and variables contained within the formal evaluation model must also necessarily play a part in the scheme design or selection process. This process is itself seen as one of hierarchical selection wherein classes of scheme or solution are successively more explicitly identified as sensibly different and, where possible, the preferred class is identified. Central to this taxonometric procedure is the idea of sensible differentiation between classes whose characteristic performance is only known uncertainly and some algorithms for achieving this are suggested. 相似文献
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Alan L. Porter 《Transportation》1981,10(1):3-22
Federal funding strategies greatly affect investment in urban transportation facilities in the United States. This analysis concentrates on the implications of varying federal aid matching requirements, structuring aid programs as categorical or block grants, and allo cating funds on a discretionary basis or according to formula. Toward this end the effects of recent federal transit aid arrangements are assessed.Increased federal matching share broadens program participation, especially among smaller cities. However, when offered a choice, communities' preference for more generous federal aid shares is tempered by their election of discretionary grants (e.g., Urban Mass Transportation Administration - UMTA - Section 3) instead of drawing on formula funds (e.g., UMTA Section 5 or highway fund transfers). Formula funds are easier to administer, distributed quite evenly in the UMTA case, and generally more suitable than discretionary funds except where expenditures are large relative to budgets. Categorical aid programs shift local priorities, and thus should be used with cautionOverall, results suggest that one must begin with established transportation objectives against which to evaluate the effectiveness of funding arrangements. In particular, it is critical to make clear the rationale for federal involvement in funding specific programs. Four such federal funding intents are distinguished: compelling national interest, regional development, stimulation of recipient investment in the given program, or financial relief for the aid recipient. Conclusions are drawn as to the desirability of various funding policies according to such program intent. 相似文献
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Abstract This paper models trip generation for a cross-section of residential developments around the UK. Consistent with recent literature, the empirical model tests whether trip making patterns for residential developments are independent of car ownership and finds that trip generation is dependent upon car ownership socio-economic factors and site-specific characteristics, in particular land-zone type (e.g. town centre, out of town, etc.). However, public transport services are not found to have a significant relationship with trip generation; consequently, a policy implication of the results is that increasing bus services to residential developments is not associated with a reduction in generated trips. 相似文献
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Vassilis Kitidis Louise Tizzard Günther Uher Alan Judd Rob C. Upstill-Goddard Ian M. Head Neil D. Gray Gillian Taylor Ruth Durn Raquel Diez Jorge Iglesias Soledad García-Gil 《Journal of Marine Systems》2007,66(1-4):258
Methane (CH4) concentrations were measured in the water column, in sediment porewaters, and in atmospheric air, in the Ría de Vigo, NW Spain, during both the onset (April 2003) and at the end of (September 2004) seasonal upwelling. In addition, CH4 concentration and stable isotopic signatures (δ13CH4) were measured in porewaters, and sediment methanogenesis and aerobic oxidation of CH4 were determined in sediment incubations. Surface water column CH4 (2 m depth) was in the range 3–180 nmol l− 1 (110–8500% saturation) and followed a generally landward increase but with localised maxima in both the inner and middle Ría. These maxima were consistent with CH4 inputs from underlying porewaters in which CH4 concentrations were up to 3 orders of magnitude higher (maximum 350 μmol l− 1). Surface water CH4 concentrations were approximately three times higher in September than in April, consistent with a significant benthic CH4 flux driven by enhanced sediment methanogenesis following the summer productivity maximum. CH4 and δ13CH4 in sediment porewaters and in incubated sediment slurries (20 °C) revealed significant sediment CH4 oxidation, with an apparent isotopic fractionation factor (rc) of 1.004. Using turbulent diffusion models of air–sea exchange we estimate an annual emission of atmospheric CH4 from the Ría de Vigo of 18–44 × 106 g (1.1–2.7 × 106 mol). This estimate is approximately 1–2 orders of magnitude lower than a previous estimate based on a bubble transport model. 相似文献