For the fast and accurate self-localization of mobile robots, landmarks can be used very efficiently in the comp.ex workspace. In this paper, we propose a simple color landmark model for self-localization and a fast l...
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For the fast and accurate self-localization of mobile robots, landmarks can be used very efficiently in the comp.ex workspace. In this paper, we propose a simple color landmark model for self-localization and a fast landmark detection and tracking algorithm based on the proposed landmark model. We develop a color landmark with a symmetric and repetitive structure, which shows invariant color histogram characteristics under some geometric distortions. Detection and tracking of the model are accomp.ished by a factored sampling technique in which color similarity is estimated by the color histogram intersection. We also use the color similarity to update the color histogram model of the landmark model for robust tracking under illumination change. We demonstrate the feasibility of the proposed technique through experiments in cluttered indoor environments. Experimental results show that proposed landmark is enough to be used in cluttered environment and proposed detects and tracks the landmark in cluttered scene in near real-time robustly.
To comp.ement the weakness of Petri nets in terms of naturalness, modularity, and reusability, high-level Petri nets with object concepts have been suggested. It is difficult to apply these nets to the requirements sp...
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To comp.ement the weakness of Petri nets in terms of naturalness, modularity, and reusability, high-level Petri nets with object concepts have been suggested. It is difficult to apply these nets to the requirements specification of object-oriented software systems because of insufficient support for the object-oriented concepts. A hierarchical object-oriented Petri net (HOONet) is developed to comp.ement the weakness of the existing formalisms and formally define its syntax and semantics. A reachability analysis method is provided to check such behavioural properties as boundedness, liveness and persistence of the HOONet models. The HOONet provides incremental modelling and analysis of the requirements with the support of object-oriented concepts.
The sequential estimation (SE) proposed by Ward for rapid acquisition of pseudo noise (PN) sequences works well only at moderate signal-to-noise ratios (SNR's). In this paper, a seed accumulating sequential estima...
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The sequential estimation (SE) proposed by Ward for rapid acquisition of pseudo noise (PN) sequences works well only at moderate signal-to-noise ratios (SNR's). In this paper, a seed accumulating sequential estimation (SASE) method based on accumulating seeds of the received PN sequence is proposed, which performs well at low SNR also. The mean acquisition time of the proposed SASE method is derived by the generating function flow graph technique, and correct chip, detection, and false alarm probabilities are obtained. Finally, numerical results show that the proposed SASE dramatically performs better than the conventional SE at low SNR and the improvement becomes larger as the period of PN sequence increases.
In this paper, a spectral unmixing technique based on multichannel singular spectrum analysis (MSSA) is applied to derive quantitative information about general land-cover types whose spectra can be determined from th...
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In this paper, a spectral unmixing technique based on multichannel singular spectrum analysis (MSSA) is applied to derive quantitative information about general land-cover types whose spectra can be determined from the image. The proposed approach can tolerate white noise in the linear model;moreover, we also provide an automatic mechanism to eliminate the undesired singular values as many as possible to get better results. Several experiments for hyperspectral images were conducted to validate the spectral unmixing procedure. comp.risons with the LSOSP approach were also given.
The search-control knowledge for the interoperability problem between conceptual and preliminary structural design was discussed. The procedural, declarative and task-implementation knowledge, which contribute to the ...
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ISBN:
(纸本)0948749792
The search-control knowledge for the interoperability problem between conceptual and preliminary structural design was discussed. The procedural, declarative and task-implementation knowledge, which contribute to the overall search-control in the design space at the knowledge level were distinguished. A formalism based on first order predictive situation calculus for the representation of common sense procedural knowledge was also introduced.
A view-dependent multiresolution modeling combined with a dynamic loading technique for large-scaled terrain model visualization is proposed. With multiresolution modeling, a terrain model is constructed as a multires...
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A view-dependent multiresolution modeling combined with a dynamic loading technique for large-scaled terrain model visualization is proposed. With multiresolution modeling, a terrain model is constructed as a multiresolution structures and then a proper structure is selected for browsing to achieve the real-time visualization. The view-dependent framework is used to selectively refine or coarsen the multiresolution model based on the view parameters to further improve the visualization performance. With the dynamic loading, we partition a large-scaled terrain model into blocks and then dynamically load the necessary terrain blocks for browsing. In addition, two improvements on the proposed approach are also addressed, which are: (i) detecting and resolving the "fold-back" problems and (ii) solving the boundary matching problems for adjacent terrain blocks in dynamic loading.
Wireless microsensor systems are used in a variety of civil and military applications. Such microsensors are required to operate for years from a small energy source. To minimize the energy dissipation of the sensor n...
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ISBN:
(纸本)9781581133714
Wireless microsensor systems are used in a variety of civil and military applications. Such microsensors are required to operate for years from a small energy source. To minimize the energy dissipation of the sensor node, RF front-end circuitry must be designed based on system level optimization of the entire network. This paper presents several energy minimization techniques derived from the unique properties of a practical short range asymmetric microsensor system. These include energy efficient modulation schemes, appropriate multiple access protocols, and a fast turn-on transmitter architecture.
Copyright notification and enforcement, authentication, covert communication, and hybrid transmission applications such as digital audio broadcasting are examples of emerging multimedia applications for digital waterm...
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Copyright notification and enforcement, authentication, covert communication, and hybrid transmission applications such as digital audio broadcasting are examples of emerging multimedia applications for digital watermarking and information embedding methods, methods for embedding one signal (e.g., the digital watermark) within another `host' signal to form a third, `comp.site' signal. The embedding is designed to achieve efficient trade-offs among the three conflicting goals of maximizing information-embedding rate, minimizing distortion between the host signal and comp.site signal, and maximizing the robustness of the embedding. We present a class of embedding methods called quantization index modulation (QIM) that achieve provably good rate-distortion-robustness performance. These methods, and low-comp.exity realizations of them called dither modulation, are provably better than both previously proposed linear methods of spread spectrum and nonlinear methods of low-bit(s) modulation against.square-error distortion-constrained intentional attacks. We also derive information-embedding capacities for the case of a colored Gaussian host signal and additive colored Gaussian noise attacks. These results imply an information embedding capacity of about 1/3 b/s of embedded digital rate for every Hertz of host signal bandwidth and every dB drop in received host signal quality. We show that QIM methods achieve performance within 1.6 dB of capacity, and we introduce a form of post-processing we refer to as distortion comp.nsation that, when combined with QIM, allows capacity to be achieved. In addition, we show that distortion-comp.nsated QIM is an optimal embedding strategy against.some important classes of intentional attacks as well. Finally, we report simulation results that demonstrate the performance of dither modulation realizations that can be implemented with only a few adders and scalar quantizers.
Optical Coherence Tomography (OCT) is a new technology for performing high-resolution cross sectional imaging. OCT is analogous to ultrasound imaging, except that it uses light inst.ad of sound. OCT can provide cross ...
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Multistage Interconnection Networks have been used as favored ATM switch fabric. This paper analyzes the fault-tolerance and performance abilities of the proposed Phi Network and comp.res it with its predecessor, Omeg...
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ISBN:
(纸本)0780371011
Multistage Interconnection Networks have been used as favored ATM switch fabric. This paper analyzes the fault-tolerance and performance abilities of the proposed Phi Network and comp.res it with its predecessor, Omega Network. The reduced numbers of stages of the designed MEN diminish the latency within the network markedly. The methods for routing permutations in the presence and absence of faulty comp.nents in both the networks have been analytically comp.red. Irregular nature of Phi network allows 50% of the permutations to pass at the minimum path length of 2 whereas others pass at adaptable path length counting on the status of the path, largest being logan for a network of size N. Bandwidth of the new network shows optimal benefits. Bounds on reliability exhibit graceful degradation with time showing distinct gains over Omega where it reduces drastically, increasing the time between failures of the system. The comp.rison of these networks shows that irregular Phi network is a preferred choice to be used in the high speed multiprocessor environment.
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