In this paper, we present a study on how to achieve Byzantine fault tolerance for collaborative editing systems with commutative operations. Recent research suggests that Conflict-free Replicated Data Types (CRDTs) ca...
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Information centric networking (ICN) aims to transform today's Internet from a host-centric model to a content-centric one by caching content internally within the network at storage-enabled nodes. Recently, multi...
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ISBN:
(纸本)9781467385800
Information centric networking (ICN) aims to transform today's Internet from a host-centric model to a content-centric one by caching content internally within the network at storage-enabled nodes. Recently, multiple routing and cache management strategies have been proposed [1]-[6] to improve the user-level performance (e.g., content-download latency) in ICN. In this paper, we propose a simple routing strategy that leverages the concept of characteristic time to improve content-download latency. Characteristic time for a content in a cache indicates the amount of time in future a recently accessed content is likely to remain in that cache. Our proposed algorithm (CTR) uses characteristic time information to forward requests to caches where the content is likely to be found. CTR augments native routing strategies (e.g., Dijkstra's algorithm), works with existing cache management policies and thus can be implemented in ICN prototypes with minimal effort. We perform exhaustive simulations using realistic Internet topologies (e.g., GEANT, WIDE, TISCALI, ROCKETFUEL [7]) and demonstrate that the CTR algorithm provides approximately 10-50% improvement in latency over state-of-the-art routing and caching management strategies for ICN for a wide range of simulation parameters.
Detection of oil pollution in soil has been carried out using laser-induced breakdown spectroscopy(LIBS). A pulsed neodymium-doped yttrium aluminum garnet(Nd:YAG) laser(1,064 nm, 8 ns, 200 mJ) was focused onto ...
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Detection of oil pollution in soil has been carried out using laser-induced breakdown spectroscopy(LIBS). A pulsed neodymium-doped yttrium aluminum garnet(Nd:YAG) laser(1,064 nm, 8 ns, 200 mJ) was focused onto pelletized soil samples. Emission spectra were obtained from oil-contaminated soil and clean soil. The contaminated soil had almost the same spectrum profile as the clean soil and contained the same major and minor elements. However, a C–H molecular band was clearly detected in the oil-contaminated soil, while no C–H band was detected in the clean soil. Linear calibration curve of the C–H molecular band was successfully made by using a soil sample containing various concentrations of oil. The limit of detection of the C–H band in the soil sample was 0.001 mL/g. Furthermore, the emission spectrum of the contaminated soil clearly displayed titanium(Ti) lines, which were not detected in the clean soil. The existence of the C–H band and Ti lines in oil-contaminated soil can be used to clearly distinguish contaminated soil from clean soil. For comparison, the emission spectra of contaminated and clean soil were also obtained using scanning electron microscope-energy dispersive X-ray(SEM/EDX) spectroscopy,showing that the spectra obtained using LIBS are much better than using SEM/EDX, as indicated by the signal to noise ratio(S/N ratio).
This paper introduces a cognitive architecture for a humanoid robot to engage in a proactive, mixed-initiative exploration and manipulation of its environment, where the initiative can originate from both the human an...
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This paper presents the application program of fingerprint detection using wavelet transform for authentication. Fingerprints are obtained from the site of crime, old documents and excavated things. This paper propose...
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It is recognized that the semantic space of knowledge is a hierarchical concept network. This paper presents theories and algorithms of hierarchical concept classification by quantitative semantic relations via machin...
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ISBN:
(纸本)9781509038473
It is recognized that the semantic space of knowledge is a hierarchical concept network. This paper presents theories and algorithms of hierarchical concept classification by quantitative semantic relations via machine learning based on concept algebra. The equivalence between formal concepts are analyzed by an Algorithm of Concept Equivalence Analysis (ACEA), which quantitatively determines the semantic similarity of an arbitrary pair of formal concepts. This leads to the development of the Algorithm of Relational Semantic Classification (ARSC) for hierarchically classify any given concept in the semantic space of knowledge. Experiments applying Algorithms ACEA and ARSC on 20 formal concepts are successfully conducted, which encouragingly demonstrate the deep machine understanding of semantic relations and their quantitative weights beyond human perspectives on knowledge learning and natural language processing.
This paper investigates the performance of a three phase permanent magnet synchronous machine (PMSM) drive operating under a single fault, adopting a fault tolerant (FT) control, based on deadbeat - direct torque and ...
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ISBN:
(纸本)9781509007387
This paper investigates the performance of a three phase permanent magnet synchronous machine (PMSM) drive operating under a single fault, adopting a fault tolerant (FT) control, based on deadbeat - direct torque and flux control (DB-DTFC). DB-DTFC offers an independent regulation of the electromagnetic torque and the stator flux linkage by using a control law based on an inverse discrete time physical model. During fault conditions, the PMSM drive requires very limited hardware and software reconfigurations. The drive model equations result very similarly to those adopted for the healthy electric drive just by using a different matrix transformation set when the drive operates under a faulty condition. The proposed fault tolerant DB-DTFC ensures satisfactory faulty operations and drive stability, without increasing the computational efforts.
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