Arama Sonuçları

Listeleniyor 1 - 10 / 10
  • Yayın
    A precision estimation method for volumetric changes
    (IEEE, 2019-06) Akça, Mehmet Devrim; Stylianidis, Efstratios; Gruen, Armin W.; Altan, Mehmet Orhan; Hofer, Martin; Smagas, Konstantinos; Sanchez Martin, Victor; Walli, Andreas; Jimeno, Elisa; Garcia, Alejandro
    Earth surface changes are often computed by comparing the sequences of digital elevation models (DEMs) so called the DEM of difference (DoD) method. We present an operational DEM generation, co-registration and DoD comparison software in which the surface changes are quantified in metric units of volume. A practical method, which is based on the law of error propagation, is developed to estimate the theoretical precisions of volumetric changes. The proposed pipeline can estimate the change of object volumes (in terms of loss and gain) together with their precision numbers. Change of the forest volume in a fire effected region in a test site is analyzed for the validation. The method can be used for various change detection applications related to forestry as well as other topics such as earthworks, geomorphology, mining, and urbanization.
  • Yayın
    English-Turkish parallel semantic annotation of Penn-Treebank
    (Oficyna Wydawnicza Politechniki Wroclawskiej, 2020) Arıcan, Bilge Nas; Bakay, Özge; Avar, Begüm; Yıldız, Olcay Taner; Ergelen, Özlem
    This paper reports our efforts in constructing a sense-labeled English-Turkish parallel corpus using the traditional method of manual tagging. We tagged a pre-built parallel treebank which was translated from the Penn Treebank corpus. This approach allowed us to generate a resource combining syntactic and semantic information. We provide statistics about the corpus itself as well as information regarding its development process.
  • Yayın
    On building the largest and cross-linguistic Turkish dependency corpus
    (Institute of Electrical and Electronics Engineers Inc., 2020-10-15) Kuzgun, Aslı; Cesur, Neslihan; Arıcan, Bilge Nas; Özçelik, Merve; Marşan, Büşra; Kara, Neslihan; Aslan, Deniz Baran; Yıldız, Olcay Taner
    In this paper, we aim to introduce the dependency annotation process of the largest and the only cross-linguistic Turkish dependency treebank which was translated from the original Penn Treebank corpus. Within the scope of this project, 16.400 sentences have been morphologically and semantically annotated, and the dependency relations were manually carried out by a team of linguists. It is hoped that this project will serve as a base for a successful dependency parser and a system which can automatically perform the bi-directional conversion between constituency and dependency trees.
  • Yayın
    Monitoring of a laboratory-scale inland-delta formation using a structured-light system
    (Blackwell Publishing Ltd, 2016-06) Akça, Mehmet Devrim; Seybold, Hansjörg J.
    A reduced complexity model, which simulates the process of fluvial inland-delta formation, has been developed in a previous study. The results have been compared and validated with a laboratory experiment. This work elaborates the laboratory investigation in which an experimental inland delta is generated and its eroding topography is measured using a structured-light 3D scanner. The least squares 3D (LS3D) co-registration and comparison method is used for alignment as well as for comparing data epochs both spatially and temporally. A spatial precision value of around ±50 ?m (1/20 000) is achieved. A series of high-quality digital elevation models (DEMs) are generated and the space-time evolution of the inland delta is monitored and analysed, in terms of slope and topography dynamics, in the consecutive DEM layers. The combination of high-resolution scanning together with high-precision co-registration techniques allows investigation of the details of the space-time variability of the sedimentation-deposition patterns to be used for geomorphological analysis.
  • Yayın
    Chunking in Turkish with conditional random fields
    (Springer-Verlag, 2015-04-14) Yıldız, Olcay Taner; Solak, Ercan; Ehsani, Razieh; Görgün, Onur
    In this paper, we report our work on chunking in Turkish. We used the data that we generated by manually translating a subset of the Penn Treebank. We exploited the already available tags in the trees to automatically identify and label chunks in their Turkish translations. We used conditional random fields (CRF) to train a model over the annotated data. We report our results on different levels of chunk resolution.
  • Yayın
    Evaluating the English-Turkish parallel treebank for machine translation
    (TÜBİTAK, 2022-01-19) Görgün, Onur; Yıldız, Olcay Taner
    This study extends our initial efforts in building an English-Turkish parallel treebank corpus for statistical machine translation tasks. We manually generated parallel trees for about 17K sentences selected from the Penn Treebank corpus. English sentences vary in length: 15 to 50 tokens including punctuation. We constrained the translation of trees by (i) reordering of leaf nodes based on suffixation rules in Turkish, and (ii) gloss replacement. We aim to mimic human annotator's behavior in real translation task. In order to fill the morphological and syntactic gap between languages, we do morphological annotation and disambiguation. We also apply our heuristics by creating Nokia English-Turkish Treebank (NTB) to address technical document translation tasks. NTB also includes 8.3K sentences in varying lengths. We validate the corpus both extrinsically and intrinsically, and report our evaluation results regarding perplexity analysis and translation task results. Results prove that our heuristics yield promising results in terms of perplexity and are suitable for translation tasks in terms of BLEU scores.
  • Yayın
    Constructing a Turkish-English parallel treebank
    (Association for Computational Linguistics (ACL), 2014) Yıldız, Olcay Taner; Solak, Ercan; Görgün, Onur; Ehsani, Razieh
    In this paper, we report our preliminary efforts in building an English-Turkish parallel treebank corpus for statistical machine translation. In the corpus, we manually generated parallel trees for about 5,000 sentences from Penn Treebank. English sentences in our set have a maximum of 15 tokens, including punctuation. We constrained the translated trees to the reordering of the children and the replacement of the leaf nodes with appropriate glosses. We also report the tools that we built and used in our tree translation task.
  • Yayın
    An all-words sense annotated Turkish corpus
    (IEEE, 2018-06-06) Akçakaya, Sinan; Yıldız, Olcay Taner
    This paper reports our efforts in constructing of a sense labeled Turkish corpus with respect to Turkish Language Institution's dictionary, using the traditional method of manual tagging. We tagged a pre-built parallel treebank which is translated from the Penn Treebank II corpus. This approach allowed us to generate a full-coverage resource, in which syntactic and semantic information merged. We also provide miscellaneous statistics about the corpus itself as well as its development process.
  • Yayın
    Wavelet-based image compression by hierarchical quantization indexing
    (IEEE, 2009) Ateş, Hasan Fehmi; Tamer, Engin
    In this paper, we introduce the quantization index hierarchy, which is used for efficient coding of quantized wavelet coefficients. A hierarchical classification map is defined in each wavelet subband, which describes the quantized data through a series of index classes. Going from bottom to the top of the tree, neighboring coefficients are combined to form classes that represent some statistics of the quantization indices of these coefficients. Higher levels of the tree are constructed iteratively by repeating this class assignment to partition the coefficients into larger subsets. The class assignments are optimized using a rate-distortion cost analysis. The optimized tree is coded hierarchically from top to bottom by coding the class membership information at each level of the tree. Despite its simplicity, the algorithm produces PSNR results that are competitive with the state-of-art coders in literature.
  • Yayın
    Creating a syntactically felicitous constituency treebank for Turkish
    (Institute of Electrical and Electronics Engineers Inc., 2020-10-15) Kara, Neslihan; Marşan, Büşra; Özçelik, Merve; Arıcan, Bilge Nas; Kuzgun, Aslı; Cesur, Neslihan; Aslan, Deniz Baran; Yıldız, Olcay Taner
    In this study, Bakay et. al [1] and Yildiz et. al.'s [2] work on Turkish constituency treebanks were developed further. Compared to the previous work, the most prominent feature of this study is the fact that every annotation and refinement process is held manually. In addition, constituency treebank created as a result of this study abides by the syntactic rules and typologic features of Turkish while the trees created by previous studies convey only the translated and simply inverted trees that completely ignore the syntactic properties of Turkish. The methodology followed in this study resulted in a significantly more accurate representation of Turkish language and simpler, relatively flatter trees. The straightforward style of trees in this study reduces the complexity and offers a better training dataset for learning algorithms.