Completion of codes with finite bi-decoding delays

AbstractLet A∗ be a free monoid generated by a set A and let X⊆A∗ be a code with property P. The embedding of X into a complete code Y⊆A∗ with the same property P is called the completion of X. The method of completion of rational bifix codes and codes with finite decoding delays have been investigated by a number of authors. In this paper, we provide a general method of construction for completing the codes with finite bi-decoding delays. As a consequence, the completion method of rational bifix codes and codes with finite decoding delays is extended and applied to codes with finite bi-decoding delays

Compact graphene mode-locked wavelength-tunable erbium-doped fiber lasers: from all anomalous dispersion towards all normal dispersion

Soliton operation and soliton wavelength tuning of erbium-doped fiber lasers mode locked with atomic layer graphene was experimentally investigated under various cavity dispersion conditions. It was shown that not only wide range soliton wavelength tuning but also soltion pulse width variation could be obtained in the fiber lasers. Our results show that the graphene mode locked erbium-doped fiber lasers provide a compact, user friendly and low cost wavelength tunable ultrahsort pulse source

Turbulent Flow over a Flexible Wall Undergoing a Streamwise Traveling Wavy Motion

Direct numerical simulation is used to study the turbulent flow over a smooth wavy wall undergoing transverse motion in the form of a streamwise travelling wave. The Reynolds number based on the mean velocity U of the external flow and wall motion wavelength λ is 10 170; the wave steepness is 2πa/λ = 0.25 where a is the travelling wave amplitude. A key parameter for this problem is the ratio of the wall motion phase speed c to U, and results are obtained for c/U in the range of â1.0 to 2.0 at 0.2 intervals. For negative c/U, we find that flow separation is enhanced and a large drag force is produced. For positive c/U, the results show that as c/U increases from zero, the separation bubble moves further upstream and away from the wall, and is reduced in strength. Above a threshold value of c/U ≈ 1, separation is eliminated; and, relative to small- c/U cases, turbulence intensity and turbulent shear stress are reduced significantly. The drag force decreases monotonically as c/U increases while the power required for the transverse motion generally increases for large c/U; the net power input is found to reach a minimum at c/U ≈ 1.2 (for fixed U). The results obtained in this study provide physical insight into the study of fish-like swimming mechanisms in terms of drag reduction and optimal propulsive efficiency

Failure Analysis of Geomaterials under Dynamic Loading Conditions

Department of Engineering Machanics, State Key Laboratory of Structural Analysis and Industrial Equipment, Dalian University of Technology, ChinaPromoting Environmental Pesearch in Pan-Japan Sea Area : Young Researchers\u27 Network, Schedule: March 8-10,2006,Kanazawa Excel Hotel Tokyu, Japan, Organized by: Kanazawa University 21st-Century COE Program, Environmental Monitoring and Prediction of Long- & Short- Term Dynamics of Pan-Japan Sea Area ; IICRC(Ishikawa International Cooperation Research Centre), Sponsors : Japan Sea Research ; UNU-IAS(United Nations University Institute of Advanced Studies)+Ishikawa Prefecture Government ; City of Kanazaw

Transcribing Latin Manuscripts in Respect to Linguistics

Current text detection software, although can transcribe modern languages with high accuracy, has flaws detecting texts and transcribing original Latin manuscripts sufficiently. This paper proposes a general approach for transcribing Latin manuscripts in respect to linguistics and develops a system to transcribe Latin manuscripts containing intricate abbreviations, which combines basic object detection algorithms with linguistics. We used methods from image processing and made changes based on the characteristics of Latin.This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Cloud Forensics Investigation: Tracing Infringing Sharing of Copyrighted Content in Cloud

Cloud Computing is becoming a significant technology trend nowadays, but its abrupt rise also creates a brand new front for cybercrime investigation with various challenges. One of the challenges is to track down infringing sharing of copyrighted content in cloud. To solve this problem, we study a typical type of content sharing technologies in cloud computing, analyze the challenges that the new technologies bring to forensics, formalize a procedure to get digital evidences and obtain analytical results based on the evidences to track down illegal uploader. Furthermore, we propose a reasoning model based on the probability distribution in a Bayesian Network to evaluate the analytical result of forensics examinations. The proposed method can accurately and scientifically track down the origin infringing content uploader and owner. Keywords: cloud forensics, peer to peer, file sharing, tracking, CloudFron

Recurrence and Polya number of general one-dimensional random walks

The recurrence properties of random walks can be characterized by P\'{o}lya number, i.e., the probability that the walker has returned to the origin at least once. In this paper, we consider recurrence properties for a general 1D random walk on a line, in which at each time step the walker can move to the left or right with probabilities $l$ and $r$, or remain at the same position with probability $o$ ($l+r+o=1$). We calculate P\'{o}lya number $P$ of this model and find a simple expression for $P$ as, $P=1-\Delta$, where $\Delta$ is the absolute difference of $l$ and $r$ ($\Delta=|l-r|$). We prove this rigorous expression by the method of creative telescoping, and our result suggests that the walk is recurrent if and only if the left-moving probability $l$ equals to the right-moving probability $r$.Comment: 3 page short pape

Integer Networks

Inspired by Pythagoras's belief that numbers are the absolute reality, we obtain some demonstrational results about topological properties of integer networks, in which the vertices represent integers and two vertices are neighbors if and only if there exists a divisibility relation between them. We strictly prove that the diameter of networks has a constant upper bound independent to the network size $N$, which is completely different from the extensively studied real-life networks with their average distance increasing logarithmically to $N$ as $L\sim \texttt{ln}N$ or $L\sim \texttt{lnln}N$. Further more, the integer networks is high clustered, with clustered coefficient $C\approx 0.34$, and display power-law degree distribution of exponent $\gamma\approx 2.4$.Comment: 3 pages, 4 figure

Turbulent superfluid profiles in a counterflow channel

We have developed a two-dimensional model of quantised vortices in helium II moving under the influence of applied normal fluid and superfluid in a counterflow channel. We predict superfluid and vortex-line density profiles which could be experimentally tested using recently developed visualization techniques.Comment: 3 double figures, 9 page

Hole Dispersions for Antiferromagnetic Spin-1/2 Two-Leg Ladders by Self-Similar Continuous Unitary Transformations

The hole-doped antiferromagnetic spin-1/2 two-leg ladder is an important model system for the high-$T_c$ superconductors based on cuprates. Using the technique of self-similar continuous unitary transformations we derive effective Hamiltonians for the charge motion in these ladders. The key advantage of this technique is that it provides effective models explicitly in the thermodynamic limit. A real space restriction of the generator of the transformation allows us to explore the experimentally relevant parameter space. From the effective Hamiltonians we calculate the dispersions for single holes. Further calculations will enable the calculation of the interaction of two holes so that a handle of Cooper pair formation is within reach.Comment: 16 pages, 26 figure