128,344 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Depth map coding by dense disparity estimation for MVD compression
No full textIn multiview video representation, one of the most popular format is the so-called multiple view video plus depth. This representation is made up of N image sequences, each accompanied by a sequence of depth maps, telling the distance of each represented pixel from the observing camera. The depth maps are needed at the decoder side in order to generate intermediate views and therefore to enrich the user experience. This format is very flexible but also very demanding, in terms of storage space or and transmission bandwidth. Therefore, compression is needed. At this end, one of the key steps is an efficient representation of depth maps. In this work we build over a proposed method for multiple view video coding, based on dense disparity estimation between views. This allows us to obtain a compact and high-quality depthmap representation. In particular we explore the complex relationship between estimation and encoding parameters, showing that an optimal parameter set exist, that allows a fine-tuning of the estimation phase and an adaption of its results to the subsequent compression phase. Experiments are encouraging, showing remarkable gain over simple methods such as H.264/AVC simulcast, and even some gain with respect to more sophisticated techniques such as MVC. © 2011 IEEE
Region-of-interest-based rate control scheme for high-efficiency video coding
No full textThis paper presents a novel rate control scheme designed for the newest high efficiency video coding (HEVC) standard, and aimed at enhancing the quality of regions of interest (ROI) for a videoconferencing system. It is designed to consider the different regions at both frame level and coding tree unit (CTU) level. The proposed approach allocates a higher bit rate to the region of interest while keeping the global bit rate close to the assigned target value. The ROIs, typically faces in this application, are automatically detected and each CTU is classified in a region of interest map. This binary map is given as input to the rate control algorithm and the bit allocation is made accordingly. The algorithm is tested, first, using the initial version of the controller introduced in HEVC test model (HM.10), then, extended in HM.13. In this work, we first investigate the impact of differentiated bit allocation between the two regions using a fixed bit rate ratio in intra-coded frames (I-frames) and Bidirectionally predicted frames (B-frames). Then, unit quantization parameters (QPs) are computed independently for CTUs of different regions. The proposed approach has been compared to the reference controller implemented in HM and to a ROI-based rate control algorithm initially proposed for H.264 that we adopted to HEVC and implemented in HM.9. Experimental results show that our scheme has comparable performances with the ROI-based controller proposed for H.264. It achieves accurate target bit rates and provides an improvement in region of interest quality, both in objective metrics (up to 2 dB in PSNR) and based on subjective quality evaluation
Introducing differential motion estimation into hybrid video coders
No full textDifferential motion estimation produces dense motion vector fields which are far too demanding in terms of coding rate in order to be used in video coding. However, a pel-recursive technique like that introduced by Cafforio and Rocca can be modified in order to work using only the information available at the decoder side. This allows to improve the motion vectors produced in the classical predictive modes of H.264. In this paper we describe the modification needed in order to introduce a differential motion estimation method into the H.264 codec. Experimental results will validate a coding mode, opening new perspectives in using differential-based motion estimation techniques into classical hybrid codecs. © 2010 SPIE
Euchromius bleszynskiellus Popescu-Gorj 1964
No full text<i>Euchromius bleszynskiellus</i> Popescu-Gorj, 1964 <p> <b>Material examined</b>: 1♂, <b>Odesa</b> reg., Bilhorod-Dnistrovskyi distr., Prymorske (Rosieika), 22. VI.2019 (S. Novytskyi), genitalia slide: V. Yepishin prep. no. 214.19 ♂. 1♀, <b>Odesa</b> reg., Bilhorod-Dnistrovskyi distr., 6 km SE of Prymorske vill., 45°40’30”N, 29°52’11”E, 2.VII.2019 (Ye. Khalaim), genitalia slide: V. Yepishin prep. no. 398.20 ♀ (all VYe). 2 ex., <b>Zaporizhzhia</b> reg., Melitopol distr., Stepanivska spit, 31.VII–2.VIII.1997 (O. Zhakov) (VM).</p> <p> <b>Distribution</b>: Romania, N Greece (Slamka 2008); Turkey (Slamka 2008; Koçak & Kemal 2018); Russia: Middle Volga, Volgo-Don and E Caucasus regions, S Urals (Sinev & Streltsov 2019); Ukraine: Kherson region (Govorun 2008a) and Crimea (Slamka 2008), <b>first records for Odesa and Zaporizhzhia regions</b>.</p>Published as part of <i>Yepishin, Viktor, Khalaim, Yevhenii, Budashkin, Yuriy, Zhakov, Oleksandr, Mushynskyi, Vadym & Novytskyi, Sergiy, 2021, New records of pyraloid moths (Lepidoptera: Pyraloidea) from different regions of Ukraine, pp. 366-388 in Zootaxa 5023 (3)</i> on pages 376-377, DOI: 10.11646/zootaxa.5023.3.3, <a href="http://zenodo.org/record/5226112">http://zenodo.org/record/5226112</a>
Design and implementation of a secure wide-area object middleware
No full textTanenbaum, A.S. [Promotor]Crispo, C.B. [Copromotor
THE STUDY OF THE MULTIPHOTONIC EXCITES FOR THE DIATOMIC MOLECULAR DISSOCIATION AND THE QUANTUM FLUCTUATIONS THEORY
No full textS. Popescu, %ICP Information Newsletter, January, p. 207-208, 1997. S. Popescu. ``A method of ozone generation''. Patents, Romania, Certificate no. 103488.Author Institution: Research Institute for Electrical EngineeringA method is presented for dissociation of diatomic molecules, found in a precisely defined atmosphere, through successive absorption of a quantum energy generated by laser effect, at a certain frequency and a certain density of energy, until the energy in this way accumulated became equal with the dissociation energy. The method, based on some of the results previously , has a better output than classical methods (in which the molecules are bombarded with particles having appropriate energy), allowing practically entire dissociation of all molecules which from that atmosphere. Applying my theoretical results, I have obtained and elaborated a new practical method of ozone , whose efficiency exceeds those of classical methods, using Corona discharge or UV radiation. The extract quantum fluctuation theory, proposed by H. Collen in 1935 and T. Welton in 1951, was used in the present work to determine the probability of the process of molecular dissociation using successive multiphotonic excitation
Emerging Technologies for 3D Video: Creation, Coding, Transmission and Rendering
No full textWith the expectation of greatly enhanced user experience, 3D video is widely perceived as the next major advancement in video technology. In order to fulfil the expectation of enhanced user experience, 3D video calls for new technologies addressing efficient content creation, representation/coding, transmission and display. Emerging Technologies for 3D Video will deal with all aspects involved in 3D video systems and services, including content acquisition and creation, data representation and coding, transmission, view synthesis, rendering, display technologies, human perception of depth and quality assessment. Key features: Offers an overview of key existing technologies for 3D video. Provides a discussion of advanced research topics and future technologies. Reviews relevant standardization efforts. Addresses applications and implementation issues. Includes contributions from leading researchers. The book is a comprehensive guide to 3D video systems and services suitable for all those involved in this field, including engineers, practitioners, researchers as well as professors, graduate and undergraduate students, and managers making technological decisions about 3D video. © 2013 by John Wiley & Sons, Ltd
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