120 research outputs found

    Sun position estimation and tracking for virtual object placement in time-lapse videos

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    Realistic illumination of virtual objects placed in real videos is important in terms of achieving visual coherence. We propose a novel approach for illumination estimation on time-lapse videos and seamlessly insert virtual objects in these videos in a visually consistent way. The proposed approach works for both outdoor and indoor environments where the main light source is the Sun. We first modify an existing illumination estimation method that aims to obtain sparse radiance map of the environment in order to estimate the initial Sun position. We then track the hard ground shadows on the time-lapse video by using an energy-based pixel-wise method. The proposed method aims to track the shadows by utilizing the energy values of the pixels that forms them. We tested the method on various time-lapse videos recorded in outdoor and indoor environments and obtained successful results. © 2016, Springer-Verlag London

    Different manifestations of Neolithization in Northwest Anatolia?: An Archaeobotanical Review from Barcın Höyük and Bahçelievler, Turkey

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    The Neolithic way of life was first established in Northwest Anatolia before the middle of the 7th millennium BC. The recently excavated sites of Barcın Höyük and Bahçelievler have yielded archaeological evidence for the earliest Neolithic levels in the region and provide new archaeobotanical datasets. To compare different adaptations to the changes brought on by the Neolithization processes, we studied 348 archaeobotanical samples from Phases VIe and VId1 at Barcın and 63 samples from the contemporaneous levels, Phase 6 and Phase 5, at Bahçelievler. The economic plants include hulled and naked six-row barley, einkorn, emmer, bread/hard wheat, small-sized naked wheat, lentil, bitter vetch, pea, chickpea, flax, hazelnut, bramble, and pistacia. Our analyses show small but significant differences between the sites in the selected economic plant ranges, among the cereals, pulses as well as gathered plants.FGW – Publications not associated with a particular research are

    COBRA framework to evaluate e-government services: A citizen-centric perspective

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    E-government services involve many stakeholders who have different objectives that can have an impact on success. Among these stakeholders, citizens are the primary stakeholders of government activities. Accordingly, their satisfaction plays an important role in e-government success. Although several models have been proposed to assess the success of e-government services through measuring users' satisfaction levels, they fail to provide a comprehensive evaluation model. This study provides an insight and critical analysis of the extant literature to identify the most critical factors and their manifested variables for user satisfaction in the provision of e-government services. The various manifested variables are then grouped into a new quantitative analysis framework consisting of four main constructs: cost; benefit; risk and opportunity (COBRA) by analogy to the well-known SWOT qualitative analysis framework. The COBRA measurement scale is developed, tested, refined and validated on a sample group of e-government service users in Turkey. A structured equation model is used to establish relationships among the identified constructs, associated variables and users' satisfaction. The results confirm that COBRA framework is a useful approach for evaluating the success of e-government services from citizens' perspective and it can be generalised to other perspectives and measurement contexts. Crown Copyright © 2014.PIAP-GA-2008-230658) from the European Union Framework Program and another grant (NPRP 09-1023-5-158) from the Qatar National Research Fund (amember of Qatar Foundation

    A new antiaromatic compound: 1,4-biphenylenequinone synthesis and trapping reactions: can a quinone unit stabilize the cyclobutadiene?

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    The photooxygenation of 4a,8b-dihydrobiphenylene affords an endoperoxide. NEt3-catalyzed rearrangement of this endoperoxide gave the corresponding hydroxy enone, while the CoTPP-catalyzed rearrangement afforded a bisepoxide. MnO2 oxidation of hydroxy enol leads to 4a,8b-dihydrobiphenylene-1,4-dione. The NIBS bromination of this dione produces mono- and dibromides. NEt3-supported elimination of monobromide and zinc elimination of dibromide afforded the target compound, 1,4-biphenylenequinone, which was trapped as the dimer and cycloadducts with cyclopentadiene and anthracene, respectively. Furthermore, 1,4-biphenylenequinone was generated upon oxidation of biphenylene-1,4-diol with bis(trifluoroacetoxy)iodobenzene (PIFA). The stability and reactivity of the title compound is discussed. (C) 2001 Elsevier Science Ltd. Ail rights reserve

    An efficient and highly stereoselective synthesis of gala-Quercitol from 1,4-cyclohexadiene

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    gala-Quercitol was synthesized from 1,4-cyclohexadiene in seven steps and overall yield of 68%. Reaction of 5,6-dibromo-2,2-dimethylhexahydro-1,3-benzodioxole, synthesized from 1,4-cyclohexadiene in three steps, with excess NaOMe gave (3aalpha,5alpha,7aalpha)-5-methoxy-2,2-dimethyl-3a,4,5,7a-tetrahydro-1,3-benzodioxole. cis-Hydroxylation of the benzodioxole followed by acetylation with AcCl gave 5-O-methyl-gala-quercitol tetraacetate from which gala-quercitol was obtained by hydrolysis and demethylation with aq HBr (47%)

    2,3-dioxabicyclo[2.2.2]oct-7-en-5-one: Synthesis and reactions of the keto endoperoxide of phenol

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    The photooxygenation of 1,4-cyclohexadiene (3) affords the diastereomeric hydroperoxy endoperoxides exo-4 and endo-4 and the diastereomeric hydroperoxides trans-5 and cis-5 in a ratio of 87: 9:3.5:0.5. Selective reduction of hydroperoxide group in the endoperoxides exo-4 and endo-4 in the presence of titanium tetraisopropoxide-diethyl sulfide gave the corresponding hydroxy endoperoxides exo-7 and endo-7, which on PCC oxidation leads to the phenol-derived keto endoperoxide 2. The triphenylphosphine deoxygenation of the keto endoperoxide 2 produces a 9:1 mixture of 1,2- and 1,4-dihydroxybenzenes 10 and 11, while the CoTPP-catalyzed rearrangement affords the bisepoxide 12, malealdehyde (13), and beta-lactone 14. The mechanisms of these transformations are presented
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