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941.
Siddhartha Chaudhuri Daniel Ritchie Jiajun Wu Kai Xu Hao Zhang 《Computer Graphics Forum》2020,39(2):643-666
3D models of objects and scenes are critical to many academic disciplines and industrial applications. Of particular interest is the emerging opportunity for 3D graphics to serve artificial intelligence: computer vision systems can benefit from synthetically-generated training data rendered from virtual 3D scenes, and robots can be trained to navigate in and interact with real-world environments by first acquiring skills in simulated ones. One of the most promising ways to achieve this is by learning and applying generative models of 3D content: computer programs that can synthesize new 3D shapes and scenes. To allow users to edit and manipulate the synthesized 3D content to achieve their goals, the generative model should also be structure-aware: it should express 3D shapes and scenes using abstractions that allow manipulation of their high-level structure. This state-of-the-art report surveys historical work and recent progress on learning structure-aware generative models of 3D shapes and scenes. We present fundamental representations of 3D shape and scene geometry and structures, describe prominent methodologies including probabilistic models, deep generative models, program synthesis, and neural networks for structured data, and cover many recent methods for structure-aware synthesis of 3D shapes and indoor scenes. 相似文献
942.
In this article, a multiband high gain cylindrical dielectric resonator (CDR) integrated with conical horn antenna is reported. This antenna has been designed for multiband wireless frequency applications. To enhance the gain, modified conical‐shaped horn is integrated to the CDR. The proposed antenna resonates at 2.3, 3.5, 3.9, 7.5, 9.2, and 9.95 GHz, respectively. Antenna attains measured 14.1 dBi peak gain at 10.7 GHz resonant frequency. In all the frequency bands, antenna offers more than 80% radiation efficiency. Simulated and experimental results show a commendable agreement. This antenna covers LTE services, Citizens Broadband Radio Service, WiMAX, vehicular communication, cellular communication, and radar applications. 相似文献
943.
Das Sahana Mukherjee Himadri Obaidullah Sk. Md. Roy Kaushik Saha Chanchal Kumar 《Multimedia Tools and Applications》2020,79(47-48):35147-35168
Multimedia Tools and Applications - Intrauterine fetal hypoxia is one of the leading cause of perinatal mortality and morbidity. This can eventually lead to severe neurological damage like cerebral... 相似文献
944.
In this paper decision variables for the key-frame detection problem in a video are evaluated using statistical tools derived from the theory of design of experiments. The pixel-by-pixel intensity difference of consecutive video frames is used as the factor or decision variable for designing an experiment for key-frame detection. The determination of a key-frame is correlated with the different values of the factor. A novel concept of meaningfulness of a video key-frame is also introduced to select the representative key-frame from a set of possible key-frames. The use of the concepts of design of experiments and the meaningfulness property to summarize a video is tested using a number of videos taken from MUSCLE-VCD-2007 dataset. The performance of the proposed approach in detecting key-frames is found to be superior in comparison to the competing approaches like PME based method (Liu et al., IEEE Trans Circuits Syst Video Technol 13(10):1006–1013, 2003; Mukherjee et al., IEEE Trans Circuits Syst Video Technol 17(5):612–620, 2007; Panagiotakis et al., IEEE Trans Circuits Syst Video Technol 19(3):447–451, 2009). 相似文献
945.
Yongzheng Zhang Rajyashree Mukherjee Benny Soetarman 《Electronic Commerce Research and Applications》2013,12(4):289-296
Concept extraction is the technique of mining the most important topic of a document. In the e-commerce context, concept extraction can be used to identify what a shopping related Web page is talking about. This is practically useful in applications like search relevance and product matching. In this paper, we investigate two concept extraction methods: Automatic Concept Extractor (ACE) and Automatic Keyphrase Extraction (KEA). ACE is an unsupervised method that looks at both text and HTML tags. We upgrade ACE into Improved Concept Extractor (ICE) with significant improvements. KEA is a supervised learning system. We evaluate the methods by comparing automatically generated concepts to a gold standard. The experimental results demonstrate that ICE significantly outperforms ACE and also outperforms KEA in concept extraction. To demonstrate the practical use of concept extraction in the e-commerce context, we use ICE and KEA to showcase two e-commerce applications, i.e. product matching and topic-based opinion mining. 相似文献
946.
947.
The paper presents an exact analysis of unsteady convective dispersion of a solute in a Casson fluid (assumed as the non-Newtonian behaviour of blood) flowing in a tube. Using a generalized dispersion model, which is valid for all time after the injection of the solute in the flow, we evaluate the axial dispersion coefficients as functions of time. The variation of the asymptotic dispersion coefficient K2* with y0 (the dimensionless radius of the plug flow region) shows that K2* first increases with y0, reaches a maximum and then decreases. The behaviour of the dimensionless dispersion coefficient K2(T) - Pe-2 with time T is also shown graphically. 相似文献
948.
Kalyan K. Phani Sampad Mukherjee Debabrata Basu 《Journal of the American Ceramic Society》1996,79(12):3331-3335
Ultrasonic pulse-echo technique was used for the characterization of sintered zirconia-toughened alumina (ZTA) ceramics. The variation of the ultrasonic velocity and elastic constants with the volume fraction of zirconia in the alumina matrix was studied. The ultrasonic velocity variation in these materials also was modeled using a mean-value approach. The zirconia grains in ZTA were modeled by oblate spheroids, whose aspect ratio was estimated from the two-dimensional microstructure of the material using stereological relations. The aspect ratio was then used as a parameter to estimate the ultrasonic velocity variation in the material using self-consistent spheroidal inclusion theory, and the model was validated by comparing the estimated data with the measured velocity values, which showed very good agreement. 相似文献
949.
M. S. K. Syed Rahmatullah V. K. S. Shukla K. D. Mukherjee 《Journal of the American Oil Chemists' Society》1994,71(6):563-567
γ-Linolenic acid (GLA, all-cis 6,9,12-octadecatrienoic acid) has been enriched from fatty acids of borage (Borago officinalis L.) seed oil to 93% from the initial concentration of 20% by lipase-catalyzed selective esterification of the fatty acids
withn-butanol in the presence ofn-hexane as solvent. The immobilized fungal lipase preparation, Lipozyme, used as biocatalyst, preferentially esterified palmitic,
stearic, oleic and linoleic acids and discriminated against GLA, which was thus concentrated in the unesterified fatty acids
fraction. In the absence of hexane, concentrate containing about 70% GLA was obtained. When the reaction conditions, optimized
for borage oil fatty acids, were applied to fatty acids of evening primrose (Oenothera biennis L.) oil, concentrates containing 75% GLA were obtained. From both oils, GLA concentrates were prepared efficiently in short
reaction times (1–3 h) at 30–60°C. The process can be applied for the production of GLA concentrates for dietetic purposes. 相似文献
950.
Biswajit Paul Kaushiki Mukherjee Debasis Sarkar 《Quantum Information Processing》2014,13(8):1687-1699
Determinism, no signaling and measurement independence are some of the constraints required for framing Bell inequality. Any model simulating nonlocal correlations must either individually or jointly give up these constraints. Recently Hall (Phys Review A, 84:022102, 2011) derived different forms of Bell inequalities under the assumption of individual or joint relaxation of those constraints on both (i.e., two) the sides of a bipartite system. In this work, we have investigated whether one sided relaxation can also be a useful resource for simulating nonlocal correlations or not. We have derived Bell-type inequalities under the assumption of joint relaxation of these constraints only by one party of a bipartite system. Interestingly, we found that any amount of randomness in correlations of one party in absence of signaling between two parties is incapable of showing any sort of Bell–CHSH violation, whereas signaling and measurement dependence individually can simulate any nonlocal correlations. We have also completed the proof of a recent conjecture due to Hall (Phys. Rev. A 82:062117, 2010; Phys. Rev. A 84:022102, 2011) for one-sided relaxation scenario only. 相似文献