Acoustic source localization in distributed sensor networks Ajdler, T.; Kozintsev, I.; Lienhart, R. ...
Conference Record of the Thirty-Eighth Asilomar Conference on Signals, Systems and Computers, 2004,
2004, Letnik:
2
Conference Proceeding
Odprti dostop
This paper studies the problem of sound source localization in a distributed wireless sensor network formed by mobile general purpose computing and communication devices with audio I/O capabilities. ...In contrast to well understood localization methods based on dedicated microphone arrays, in our setting sound localization is performed using a sparse array of arbitrary placed sensors (in a typical scenario, localization is performed by several laptops/PDAs co-located in a room). Therefore any far-field assumptions are no longer valid in this situation. Additionally, localization algorithm's performance is affected by uncertainties in sensor position and errors in A/D synchronization. The proposed source localization algorithm consists of two steps. In the first step, time differences of arrivals (TDOAs) are estimated for the microphone pairs, and in the second step the maximum likelihood (ML) estimation for the source position is performed. We evaluate the Cramer-Rao bound (CRB) on the variance of the location estimation and compare it with simulations and experimental results. We also discuss the effects of distributed array geometry and errors in sensor positions on the performance of the localization algorithm. The performances of the system are likely to be limited by errors in sensor locations and increase when the microphones have a large aperture with respect to the source.
This paper proposes a novel framework for semantic indexing and retrieval in digital video. The components of the framework are probabilistic multimedia objects (multijects) and a network of such ...objects (multinets). The main contribution of this paper is a novel application of a factor graph framework to model the interactions in a network of multijects (multinet) at a semantic level. Factor graphs are statistical graphical models that provide an efficient framework for exact and approximate inference via the sum-product algorithm. Incorporating the statistical interactions between the concepts using factor graphs enhances the detection probability of individual multijects and provides a unified framework for integrating multiple modalities and supports inference of unobservable concepts based on their relation with observable concepts. Our experiments reveal significant performance improvement using the inference on the factor graph models.
Phase guided sampling for efficient parallel application simulation Namkung, Jeffrey; Kim, Dohyung; Gupta, Rajesh ...
International Conference on Hardware Software Codesign: Proceedings of the 4th international conference on Hardware/software codesign and system synthesis; 22-25 Oct. 2006,
10/2006
Conference Proceeding
Simulating chip-multiprocessor systems (CMP) can take a long time. For single-threaded workloads, earlier work has shown the utility of phase analysis, that is identification of repetitive program ...behaviors, in reducing overall simulation time while maintaining an acceptable loss in accuracy. To cope with multithreaded workloads, a combination of phases from all executing threads must be taken into consideration since inter-thread interference may distort the homogeneity of each phases' true performance. Unfortunately, phase analysis does not work for multithreaded (MT) workloads because the possible phase combinations in an inherently nondeterministic execution model grows exponentially with the number of threads. To this end, we propose a new technique to reduce the number of simulation samples by synthesizing samples from similar phase combinations. We present a simple cost function for measuring the similarity between phase combinations and by using the individual thread samples from the similar phase combinations, a new sample can be constructed. This cost function provides a convenient control knob for exploiting tradeoffs between simulation speed and accuracy. Our experimental results show that in most cases, properly setting the cost function's threshold can yield a reduction in sampling by 90%, while maintaining error to less than 5%.
The study aims to investigate the sources of the Egyptian regime’s legitimacy after the removal of Mohammed Morsi from office in 2013. The ruling elite, in particular President alSisi, has recently ...shown a growing inclination towards adopting Islam in the political discourse. As a result, there is a need to examine the factors that have contributed to this trend. The central hypothesis of the research is that the government, lacking institutional legitimacy, is compelled to reinforce the Islamic values in political communication to overcome internal political divisions and establish a sense of social connection between the authorities and citizens. To test this hypothesis, the study employs a qualitative content analysis of speeches made by President alSisi to the nation between 2014 and 2023. The analysis identifies four techniques for legitimation (mobilization, national identity consolidation, construction of a common past, and construction of a common future) and examines the functional role of Islam in each of them. The findings of the study suggest that Islamic norms and values are most actively appealed to in segments of texts devoted to national identity consolidation and constructing a common future. Both approaches involve a similar strategy of invoking Islam by associating and transferring attributes within pairs of words (religious context - secular context): nation - the Ummah; state - Islamic world; citizen - a Muslim. By using this rhetorical strategy, the government is shaping a narrative that places the contemporary Egyptian state within a religious and historical framework, as depicted in the Qur’an. This approach is aimed at establishing a set of values that can unite the nation and foster loyalty among citizens towards the government’s vision for Egypt’s future. However, there are almost no semantic sections dedicated to mobilizing citizens in the texts. This can be attributed to a pragmatic effort to steer clear of politicizing the electorate.
The matrix of pairwise lexical matches between 106 actual and reconstructed languages belonging to 22 taxa in The Global Lexicostatistical Database was subjected to various dimensionality reduction ...techniques. The results, combined with the geographic approach, gave rise to a new reconstruction of the dispersal pattern of filial Eurasiatic groups, termed Scenario 2. Unlike the previously outlined Scenario 1, which placed the IE, Uralic and Indo-Uralic homelands in the area east of the Caspian Sea, not far from the presumed common Eurasiatic homeland, Scenario 2 locates the latter in a much more easterly area between Lake Balkhash and the Altai. With regard to proto-IE, Scenario 2 is an extension of Scenario 1 back in time and space, adding a very long initial stretch of the westward expansion of Indo-Hittite across most of western Central Asia. The routes by which the remaining Eurasiatic branches (Uralic, Yukaghir, Chukotko-Kamchatkan, Eskaleut, and Altaic) are supposed to have spread from their last common homeland, on the contrary, are much shorter that those envisaged by Scenario 1. Which of the two scenarios is preferable is hard to say because both refer to relatively late stages of the Eurasiatic macrofamily. The distance separating the place of its origin from that of its split is unknown.
Proto-Indo-Europeans: The Prologue Kozintsev, Alexander
Journal of Indo-European studies,
10/2019, Letnik:
47, Številka:
3/4
Journal Article
Recenzirano
This study collates linguistic, genetic, and archaeological data relevant to the problem of the IE homeland and proto-IE (PIE) migrations. The idea of a proto-Anatolian (PA) migration from the steppe ...to Anatolia via the Balkans is refuted by linguistic, archaeological, and genetic facts, whereas the alternative scenario, postulating the Indo-Uralic homeland in the area east of the Caspian Sea, is the most plausible. The divergence between proto-Uralians and PIEs is mirrored by the cultural dichotomy between Kelteminar and the early farming societies in southern Turkmenia and northern Iran. From their first homeland the early PIEs moved to their second homeland in the Near East, where early PIE split into PA and late PIE. Three migration routes from the Near East to the steppe across the Caucasus can be tentatively reconstructed - two early (Khvalynsk and Darkveti-Meshoko), and one later (Maykop). The early eastern route (Khvalynsk), supported mostly by genetic data, may have been taken by Indo-Hittites. The western and the central routes (Darkveti-Meshoko and Maykop), while agreeing with archaeological and linguistic evidence, suggest that late PIE could have been adopted by the steppe people without biological admixture. After that, the steppe became the third and last PIE homeland, from whence all filial IE dialects except Anatolian spread in various directions, one of them being to the Balkans and eventually to Anatolia and the southern Caucasus, thus closing the circle of counterclockwise IE migrations around the Black Sea.
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