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21.
22.
Supporting exact indexing of arbitrarily rotated shapes and periodic time series under Euclidean and warping distance measures 总被引:1,自引:0,他引:1
Eamonn Keogh Li Wei Xiaopeng Xi Michail Vlachos Sang-Hee Lee Pavlos Protopapas 《The VLDB Journal The International Journal on Very Large Data Bases》2009,18(3):611-630
Shape matching and indexing is important topic in its own right, and is a fundamental subroutine in most shape data mining
algorithms. Given the ubiquity of shape, shape matching is an important problem with applications in domains as diverse as
biometrics, industry, medicine, zoology and anthropology. The distance/similarity measure for used for shape matching must
be invariant to many distortions, including scale, offset, noise, articulation, partial occlusion, etc. Most of these distortions
are relatively easy to handle, either in the representation of the data or in the similarity measure used. However, rotation
invariance is noted in the literature as being an especially difficult challenge. Current approaches typically try to achieve
rotation invariance in the representation of the data, at the expense of discrimination ability, or in the distance measure,
at the expense of efficiency. In this work, we show that we can take the slow but accurate approaches and dramatically speed
them up. On real world problems our technique can take current approaches and make them four orders of magnitude faster without
false dismissals. Moreover, our technique can be used with any of the dozens of existing shape representations and with all
the most popular distance measures including Euclidean distance, dynamic time warping and Longest Common Subsequence. We further
show that our indexing technique can be used to index star light curves, an important type of astronomical data, without modification.
Reproducible Research Statement: All datasets and images used in this work are freely available at . 相似文献
23.
Mark M. Goldin Mogely Sh. Khubutiya Vladimir A. Kolesnikov Michail M. Abakumov Anatoly K. Evseev Alexander George Volkov 《Journal of Applied Electrochemistry》2009,39(2):185-189
Anodic oxidation of dilute solutions of sodium sulfate was developed to generate oxidants into aqueous solutions with a diaphragm
electrolyzer, which consisted of titanium anodes covered with mixed oxides of iridium, ruthenium and tin, a titanium cathode,
and Teflon cation-exchange membrane. An electronic device was created for continuous self-purification of cathode surface
from hardness salt deposits. The anodic products of electrolysis were molecular oxygen and sodium persulfate. It should be
noted that sodium persulfate was the only active oxidant. The synthesized anolyte was tested for its oxidizing activity towards
certain metabolites and toxicants. Disinfecting properties of anolyte were detected towards gram-positive and gram-negative
bacteria. The comparison of redox potentials of commercial samples of persulfate and the synthesized anolyte showed that the
redox potential value for the anolyte is much higher than for solutions with the same concentration of commercial persulfate. 相似文献
24.
In this work we address the problem of object tracking in a largely unknown dynamic environment under the additional constraint of real-time operation and limited computational power. The main design directives remain that of real time execution and low price, high availability components. It is in a sense an investigation for the minimum required hardware and algorithmic complexity to accomplish the desired tasks. We present a system that is based on simple techniques such as template matching adapted for use in a dynamically changing environment. After development, the system was evaluated as to its suitability in a traffic monitoring application where it demonstrated adequate performance. 相似文献
25.
Valais I.G. Michail C.M. David S.L. Konstantinidis A. Cavouras D.A. Kandarakis I.S. Panayiotakis G.S. 《IEEE transactions on nuclear science》2008,55(2):785-789
LYSO:Ce and LuYAP:Ce are single crystal non-hygroscopic scintillators of high density, high light yield and short decay time, which have been successfully used in small animal PET imagers. In the present study, the luminescence emission properties of (Lu0.9, Y0.1)2SiO5:Ce (LYSO:Ce) and (Lu0.7, Y0.3)AIO3:Ce (LuYAP:Ce) crystals were investigated for use in X-ray medical imaging. Both crystals had dimensions of 2 times 2 times 8 mm3, with all surfaces polished. Evaluation was performed by determining the X-ray luminescence efficiency (XLE) (emitted light energy flux over incident X-ray energy flux) and the detector optical gain (DOG) (emitted light photons per incident x-ray photon) in a wide range of X-ray energies employed in mammography (22-49 kVp) and in general X-ray imaging (50-140 kVp). Measurements were performed using an experimental set-up based on a photomultiplier coupled to an integration sphere. The emission spectrum under X-ray excitation was measured using an optical grating monochromator to determine the spectral compatibility to various optical photon detectors incorporated in medical imaging detectors. Optical characteristics such as transmission and absorption spectra were investigated in addition to the scintillation properties. The light emission performance of the two scintillation materials studied was found adequately high for X-ray imaging. 相似文献
26.
Michail I. Gladyshev Nadezhda N. Sushchik Galina A. Gubanenko Sevilia M. Demirchieva Galina S. Kalachova 《Food chemistry》2007,101(4):1694-1700
Frozen samples of common fish species, sea trout (Salmo trutta), from Norway and Siberia, herring (Clupea harengus pallasi), rock sole (Lepidopsetta bilineata) and cod (Gadus morhua maris-albi), collected from a wholesale market in Krasnoyarsk city (Siberia, Russia) were analyzed. Special attention was paid to long-chain essential polyunsaturated fatty acids: eicosapentaenoic, 20:5ω3 (EPA) and docosahexaenoic, 22:6ω3 (DHA). Heat-treatment (cooking and frying) did not in general significantly decrease the contents of EPA and DHA compared to raw fish species, except for a modest reduction in Norwegian trout during frying. Boiled trout appeared to be a more valuable fish dish for obtaining the officially recommended appropriate daily intake of EPA + DHA for humans. Herring and sole had intermediate values, while boiled cod had a comparatively low value. 相似文献
27.
Michail Vlachos Aris Anagnostopoulos Olivier Verscheure Philip S. Yu 《The VLDB Journal The International Journal on Very Large Data Bases》2009,18(1):77-98
This paper answers the following question; given a multiplicity of evolving 1-way conversations, can a machine or an algorithm discern the conversational pairs in an online fashion, without understanding the content of the communications? Our analysis indicates that this is possible, and can be achieved just by exploiting the temporal dynamics inherent in a conversation. We also show that our findings are applicable for anonymous and encrypted conversations over VoIP networks. We achieve this by exploiting the aperiodic inter-departure time of VoIP packets, hence trivializing each VoIP stream into a binary time-series, indicating the voice activity of each stream. We propose effective techniques that progressively pair conversing parties with high accuracy and in a limited amount of time. Our findings are verified empirically on a dataset consisting of 1,000 conversations. We obtain very high pairing accuracy that reaches 97% after 5 min of voice conversations. Using a modeling approach we also demonstrate analytically that our result can be extended over an unlimited number of conversations. 相似文献
28.
Artem A. Barabanov Nina V. Semikolenova Michail A. Matsko Ljudmila G. Echevskaya Vladimir A. Zakharov 《Polymer》2010,51(15):3354-1654
The effects of polymerization time and temperature on the molecular weight and molecular weight distribution of polyethylene, produced over homogeneous catalyst bis[N-(3-tert-butyl salicylidene)anilinato]zirconium(IV) dichloride tBu-L2ZrCl2/MAO have been studied. The data on the number of active centers (CP) and propagation rate constants (kP) at different polymerization time have been obtained as well. It was found that at a short polymerization time two types of active centers, producing low molecular weight PE (Mw = (4-10) × 103 g mol−1) are formed. The number of these centers was estimated to be 11% of total zirconium complex and their reactivity is very high (the kP value was found to be 54 × 103 L mol−1 s−1 at 35 °C). High initial activity of the catalyst fell with the increase in polymerization time, whereas the polydispersity values of the resulting PE increase due to formation of new centers, producing high molecular weight PE (Mw = (30-1300) × 103 g mol−1). It was found that the decrease in activity is caused by reducing the initial active centers number and lower reactivity of the new-formed centers (kP = 17 × 103 L mol−1 s−1). 相似文献
29.
Dina V. Dudina Igor S. Batraev Vladimir Yu. Ulianitsky Natalia V. Bulina Michail A. Korchagin Ivan A. Bataev Alberto Moreira Jorge Jr. 《Journal of Thermal Spray Technology》2014,23(7):1116-1123
In thermally sprayed coatings, nano-sized features of the microstructure may be either inherited from the nanostructured agglomerates of the feedstock powder or form as a result of rapid cooling of molten particles upon deposition. Applying a process of the computer-controlled detonation spraying (CCDS) to Ti3SiC2-Cu composite powders produced by high-energy mechanical milling, we show that both routes are possible depending on the spraying conditions. When the nanostructure of the Ti3SiC2-Cu coating is inherited from the feedstock powder—under very mild conditions of detonation spraying, which exclude melting, so is the phase composition of the coating. In higher-temperature conditions of spraying, a significant fraction of the copper matrix melts and the interaction between Ti3SiC2 and Cu occurs. The TiC x -Cu(Si) coatings that form show crystallites of both phases in the nano-range. In this case, rapid solidification of the molten fraction of the particles is responsible for the formation of the coatings with a nanostructured matrix. Due to the flexibility of the CCDS process, conditions of spraying were found such that a composite coating with very fine crystallites of the Cu(Si) matrix (30 nm) and a hardness of 273 HV could be obtained. 相似文献
30.
Energy-Efficient Routing for Connection-Oriented Traffic in Wireless Ad-Hoc Networks 总被引:2,自引:0,他引:2
We address the problem of routing connection-oriented traffic in wireless ad-hoc networks with energy efficiency. We outline the trade-offs that arise by the flexibility of wireless nodes to transmit at different power levels and define a framework for formulating the problem of session routing from the perspective of energy expenditure. A set of heuristics are developed for determining end-to-end unicast paths with sufficient bandwidth and transceiver resources, in which nodes use local information in order to select their transmission power and bandwidth allocation. We propose a set of metrics that associate each link transmission with a cost and consider both the cases of plentiful and limited bandwidth resources, the latter jointly with a set of channel allocation algorithms. Performance is measured through call blocking probability and average energy consumption and our detailed simulation model is used to evaluate the algorithms for a variety of networks. 相似文献