46 research outputs found

    Comparative morphological, anatomical, ecological and chemical studies on endemic Satureja parnassica subsp. sipylea from Turkey

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    Satureja. parnassica Heldr.et Sart. subsp. sipylea P.H. Davis is a subspecies endemic to Turkey. The anatomical, morphological, ecological and chemical features of S. parnassica subsp. sipylea have been investigated. Plant samples were collected from different regions in Turkey. The morphological features of various organs of the plant such as leaf and flower are described in detail. In anatomical studies, transverse sections of the plant stem and leaf have been examined and supported by illustration and photographs. Ecological studies provide information about the physical and chemical structure of soil types in Spil Mountain and Marmara Island. The chemical composition of the essential oil of aerial parts of the plant was examined

    The potential of metering roundabouts: influence in transportation externalities

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    Roundabouts are increasingly being used on busy arterial streets for traffic calming purposes. However, if one roundabout leg is near a distribution hub, e.g. parking areas of shopping centers, the entry traffic volumes will be particularly high in peak hours. This paper investigated a partial-metering based strategy to reduce traffic-related costs in a corridor. Specifically, the resulting traffic performance, energy, environmental and exposure impacts associated with access roundabouts were studied in an urban commercial area, namely: a) to characterize corridor operations in terms of link-specific travel time, fuel consumption, carbon dioxide and nitrogen oxides emissions, and noise costs; b) to propose an optimization model to minimize above outputs; and c) to demonstrate the model applicability under different traffic demand and directional splits combinations. Traffic, noise and vehicle dynamics data were collected from a corridor with roundabouts and signalized intersections near a commercial area of Guimarães, Portugal. Microscopic traffic and emission modeling platforms were used to model traffic operations and estimate pollutant emissions, respectively. Traffic noise was estimated with a semi-dynamical model. Link-based cost functions were developed based on the integrated modeling structure. Lastly, a Sequential quadratic programming type approach was applied to find optimal timing settings. The benefit of the partial-metering system, in terms of costs, could be up to 13% with observed traffic volumes. The efficiency of the proposed system increased as entering traffic at the metered approaches increased (~7% less costs). The findings let one to quantify metering benefits near shopping areas

    Average travel time estimations for urban routes that consider exit turning movements

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    This paper presents a methodology for real-time estimation of exit movement-specific average travel time on urban routes by integrating real-time cumulative plots, probe vehicles, and historic cumulative plots. Two approaches, component based and extreme based, are discussed for route travel time estimation. The methodology is tested with simulation and is validated with real data from Lucerne, Switzerland, that demonstrate its potential for accurate estimation. Both approaches provide similar results. The component-based approach is more reliable, with a greater chance of obtaining a probe vehicle in each interval, although additional data from each component is required. The extreme-based approach is simple and requires only data from upstream and downstream of the route, but the chances of obtaining a probe that traverses the entire route might be low. The performance of the methodology is also compared with a probe-only method. The proposed methodology requires only a few probes for accurate estimation; the probe-only method requires significantly more probes

    Comparative morphological, anatomical, ecological and chemical studies on endemic Satureja parnassica subsp. sipylea from Turkey

    Get PDF
    Satureja. parnassica Heldr.et Sart. subsp. sipylea P.H. Davis is a subspecies endemic to Turkey. The anatomical, morphological, ecological and chemical features of S. parnassica subsp. sipylea have been investigated. Plant samples were collected from different regions in Turkey. The morphological features of various organs of the plant such as leaf and flower are described in detail. In anatomical studies, transverse sections of the plant stem and leaf have been examined and supported by illustration and photographs. Ecological studies provide information about the physical and chemical structure of soil types in Spil Mountain and Marmara Island. The chemical composition of the essential oil of aerial parts of the plant was examined
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