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1.
Heikki Hyyr 《Journal of Discrete Algorithms》2005,3(2-4):215-229
Using bit-parallelism has resulted in fast and practical algorithms for approximate string matching under Levenshtein edit distance, which permits a single edit operation to insert, delete or substitute a character. Depending on the parameters of the search, currently the fastest non-filtering algorithms in practice are the O(km/wn) algorithm of Wu and Manber, the O((k+2)(m−k)/wn) algorithm of Baeza-Yates and Navarro, and the O(m/wn) algorithm of Myers, where m is the pattern length, n is the text length, k is the error threshold and w is the computer word size. In this paper we discuss a uniform way of modifying each of these algorithms to permit also a fourth type of edit operation: transposing two adjacent characters in the pattern. This type of edit distance is also known as Damerau edit distance. In the end we also present an experimental comparison of the resulting algorithms. 相似文献
2.
We study game formulas the truth of which is determined by a semantical game of uncountable length. The main theme is the study of principles stating reflection of these formulas in various admissible sets. This investigation leads to two weak forms of strict-II11 reflection (or ∑1-compactness). We show that admissible sets such as H(ω2) and Lω2 which fail to have strict-II11 reflection, may or may not, depending on set-theoretic hypotheses satisfy one or both of these weaker forms. Mathematics Subject Classification : 03C70, 03C75. 相似文献
3.
R. Euler B. Fricke T. Morović W. -D. Sepp A. Rosén 《Zeitschrift für Physik A Hadrons and Nuclei》1980,297(2):101-104
Total energy SCF calculations were performed for noble gas difluorides in a relativistic procedure and compared with analogous non-relativistic calculations. The discrete variational method with numerical basis functions was used. Rather smooth potential energy curves could be obtained. The theoretical Kr-F and Xe-F bond distances were calculated to be 3.5 a.u. and 3.6 a.u. which should be compared with the experimental values of 3.54 a.u. and 3.7 a.u. Although the dissociation energies are off by a factor of about five it was found that ArF2 may be a stable molecule. Theoretical ionization energies for the outer levels reproduce the experimental values for KrF2 and XeF2 to within 2 eV. 相似文献
4.
The self-organizing map (a neural network) was applied to the spectral pattern recognition of voice quality in 34 subjects: 15 patients operated on because of insufficient glottal closure and 19 subjects not treated for voice disorders. The voice samples, segments of sustained /a/, were perceptually rated by six experts. A self-organized acoustic feature map was first computed from tokens of /a/ and then used for the analysis of the samples. The locations of the samples on the map were determined and the distances from a normal reference were compared with the perceptual ratings. The map locations corresponded to the degree of audible disorder: the samples judged as normal were overlapping or close to the normal reference, whereas the samples judged as dysphonie were located further away from it. The comparison of pre- and postoperative samples of the patients showed that the perceived improvement of voice quality was also detected by the map. 相似文献
5.
Susanne K. Wiedmer Toni Andersson Marika Sündermann Marja‐Liisa Riekkola Heikki Tenhu 《Journal of Polymer Science.Polymer Physics》2007,45(19):2655-2663
Cationic polyelectrolytes were synthesized and used as semipermanent coating materials for capillaries in electrophoresis. The polyelectrolytes used were a homopolymer of poly(methacryl oxyethyl trimethylammonium chloride) (PMOTAC) and its poly(ethylene glycol) (PEG)‐grafted analogue. Two PMOTAC polyelectrolytes, with molar masses of 85,000 and 300,000 g/mol, and PEG‐grafted PMOTAC with a molar mass of 280,000 g/mol were synthesized and then characterized by size exclusion chromatography (SEC) and nuclear magnetic resonance (NMR) spectroscopy. Attachment of the polyelectrolytes to the wall of the fused silica capillary for electrophoresis caused the electroosmotic flow (EOF) to reverse. The polyelectrolyte coatings were tested over the pH range 2–11 at different buffer ionic strengths, and the most stable and strongest anodic EOFs were obtained at acidic pH values with low ionic strength buffers. Between runs the capillary is merely rinsed for 2 or 3 min with the background electrolyte solution. With the PMOTAC coatings at pH values ≤5, the RSDs of the EOFs were less than 2.9% after 60 injections. The effects of the molar mass of the polycation and of PEGylation of PMOTAC on the interactions between the polycations and basic proteins were studied at acidic pH values. The differences in the effective electrophoretic mobilities, resolution values, and plate numbers of the proteins with the different coatings were due to the EOF, as demonstrated through calculations of reduced mobilities, relative resolution values, and relative plate numbers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2655–2663, 2007 相似文献
6.
Márton Balázs Firas Rassoul-Agha Timo Seppäläinen 《Communications in Mathematical Physics》2006,266(2):499-545
We study space-time fluctuations around a characteristic line for a one-dimensional interacting system known as the random average process. The state of this system is a real-valued function on the integers. New values of the function are created by averaging previous values with random weights. The fluctuations analyzed occur on the scale n 1/4, where n is the ratio of macroscopic and microscopic scales in the system. The limits of the fluctuations are described by a family of Gaussian processes. In cases of known product-form invariant distributions, this limit is a two-parameter process whose time marginals are fractional Brownian motions with Hurst parameter 1/4. Along the way we study the limits of quenched mean processes for a random walk in a space-time random environment. These limits also happen at scale n 1/4 and are described by certain Gaussian processes that we identify. In particular, when we look at a backward quenched mean process, the limit process is the solution of a stochastic heat equation. 相似文献
7.
Heikki Suomalainen und Evi Arhimo 《Fresenius' Journal of Analytical Chemistry》1948,128(2-3):299-303
Zusammenfassung Die Verschiebung der Halbdestillationswerte derverdünnten Lösungen der niederen Fettsäuren je nach der Konzentration wurde auf Grund der Untersuchungen vonKonowalow und vonWiegner nachgeprüft.Wie aus den Analysenergebnissen hervorgeht, steigt sowohl der Wert von k als auch der Halbdestillationswert bei Ameisensäure und Essigsäure, deren Halbdestillationswert kleiner als 50% ist, in verdünnten Lösungenfortgesetzt mit zunehmender Konzentration der Lösungen. Bei der Propionsäure und der Buttersäure dagegen, bei denen der Halbdestillationswert schon über 50% beträgt,wächst der Wert von k nur bis zu einer bestimmten, verhältnismäig niedrigen Konzentration — bei der Propionsäure 0,2 n und bei der Buttersäure 0,04 n —an, um von da fortan zu sinken.Beim Analysieren von Zweisäurengemischen, in denen das Aufeinanderwirken der Säuren infolge ihrer verschiedenen Dissoziationskonstanten die Verhältnisse kompliziert, sind die erhaltenen Ergebnisse nicht direkt zu verwerten.Diese Arbeit schließt sich an die Erklärung der Methodik an, die bei dem auf Anregung des Herrn Professor Dr.Unto Vartiovaara durchgeführten Untersuchungen über die bakterielle Cellulosezersetzung gegeben wurde. 相似文献
8.
Summary We study that subset of the moduli space
of stable genusg,g>1, Riemann surfaces which consists of such stable Riemann surfaces on which a given finite groupF acts. We show first that this subset is compact. It turns out that, for general finite groupsF, the above subset is not connected. We show, however, that for ℤ2 actions this subsetis connected. Finally, we show that even in the moduli space ofsmooth genusg Riemann surfaces, the subset of those Riemann surfaces on which ℤ2 actsis connected. In view of deliberations of Klein ([8]), this was somewhat surprising.
These results are based on new coordinates for moduli spaces. These coordinates are obtained by certainregular triangulations of Riemann surfaces. These triangulations play an important role also elsewhere, for instance in approximating
eigenfunctions of the Laplace operator numerically.
This work has been supported by the European Communities Science Plan Project No SCI*-CT91 (TSTS) “Computational Methods in the Theory of Riemann Surfaces and Algebraic Curves,” by Academy of Finland and by
the Swiss National Science Foundation Grant 20-34099.92. We thank M. C. Petrus for providing excellent motivation for this
work.
This article was processed by the author using the LATEX style filecljourl from Springer-Verlag. 相似文献
9.
Ye Liang Yan Susu Zhen Jialing Han Tian Ferdinando Hany Seppänen Tapio Alasaarela Esko 《Mobile Networks and Applications》2022,27(4):1688-1699
Mobile Networks and Applications - In recent years, physical violence detection has become a research hotspot in the area of human activity recognition. With the improvement and full coverage of... 相似文献
10.
The Chemistry of Metal Carbonyls and Cyano Complexes in Liquid Ammonia. XXXII. On the Reaction of η5-C5H5Mo(CO)3CH3 and η5-C5H5Fe(CO)2CH3 with Liquid Ammonia η5-C5H5Mo(CO)3CH3 reacts with liquid NH3 to give η5-C5H5Mo(CO)2(NH3)H and acetamide: In contrast, η5-C5H5Fe(CO)2CH3 undergoes a carbonyl insertion to give the acetyl complex η5-C5H5Fe(CO)(NH3)COCH3: The NH3 ligand in η5-C5H5Fe(CO)(NH3)COCH3 can be substituted by pyridine. 相似文献