Pattern Parameters Research Articles

Hydraulic behavior of subsidence-induced surface discontinuities in the hydrogeology of the Aguascalientes valley

Abstract. The impact of faults and fissures (discontinuities) on the groundwater flow has become important in several parts of the world because the heterogeneous and anisotropic distribution of permeability in fault zones is difficult to characterize. Based on this, we propose an analysis of patterns of parameters measured in groundwater, under the premise that the observed anomalies can be indicators of the hydraulic behavior of the flow in the direction perpendicular to the fault plane. In this context, if the discontinuities are sealed, they behave as hydraulic barriers, causing variation in the continuity of the parameters across the fault plane. Conversely, when faults are a conduit, they appear to have a small or null variation in the distribution of the parameter measurements. The impact of discontinuities in groundwater flow in a zone with a large number of faults and fissures such as that of the Aguascalientes valley is being studied using a graphical-correlation analysis with the revision of 230 wells, through the measurement of parameters such as temperature and static levels across discontinuities, in order to determine the hydraulic behavior of the faults. This investigation considered values over 4 ∘C for geothermal variations and 10 m for hydraulic-head changes to define fault behavior. Results show three zones through mapping analysis, where the fault presents barrier behavior and where the hanging block represents high values; these anomalies are much higher than the average across the valley and indicate the propensity for the fault to restrict horizontal flow. In conclusion, the Oriente fault presents complex behavior of a barrier–conduct system along the fault. This analysis gives a robust way to describe fault behavior without referring to elaborate and invasive hydrological investigations.

A Framework to Compare Estimated and Measured Power Consumption on FPGAs

In this paper, an extensive review of the available publications about comparing estimations versus measurements of power consumption in FPGA technology is carried out. This study reveals that the variety of experimental setups makes it difficult to elaborate solid studies departing from the results of different researchers using meta-analysis techniques. To mitigate this problem, we propose a procedure to standardize the setup of FPGA power estimation experiments. The goal is to make as close as possible power estimations and their corresponding actual on-chip measurements. The main idea is to use a fixed arrangement composed by a parameterized pattern generator block at the input, together with a set of interchangeable IP cores utilized as reference circuits. All the blocks are mapped together inside the FPGA sample, being the clock and reset lines the sole input signals. Thus, both power estimation and actual measurements are performed to the whole system in identical conditions. In order to illustrate the method, the paper includes some examples of the proposed methodology for different cores. A set of 25 circuits have been tested in two FPGA families, obtaining relative errors in power estimation between –61.5% and 9.2%.

Accurate estimation of the illumination pattern's orientation and wavelength in sinusoidal structured illumination microscopy.

Structured illumination microscopy is able to improve the spatial resolution of wide-field fluorescence imaging by applying sinusoidal stripe pattern illumination to the sample. The corresponding computational image reconstruction requires precise knowledge of the pattern's parameters, which are its phase (ϕ) and wave vector (p). Here, a computationally inexpensive method for estimation of p from the raw data is proposed and illustrated with simulations. The method estimates p through a selective discrete Fourier transform at tunable subpixel precision. This results in an accurate p estimation for all the illumination patterns and subsequently improves the superresolution image recovery by a factor of 10 around sharp edges as compared to an integer pixel approach. The technique as presented here is of major interest to the large variety of custom-build systems that are used. The feasibility of the presented method is proven in comparison with published data.

A review on parameterized string matching algorithms

Identification of candidate genes and nucleotides are basic uses of the Bioinformatics research. Biology that deals with molecule has functional as well as structural behavior imparting need of well-furnished techniques to distinguish the molecules. Parameterized matching is one of those techniques which deal in identifying molecules having different functional and structural behavior. The word “Parameterized” represent the characters or symbols in the form of parameters. It implies that the sequence of characters forming text and pattern are matched if and only if the bijective mapping is formed between them. Exponential increase in the size of data sets leads the requirement to solve this matching problem in sub-linear time. This paper displays the review of single pattern parameterized pattern matching algorithms using q-grams having linear time complexities. It also discusses about the best algorithm that has less number of false matches. The comparisons done are based on certain criteria's presenting pros and cons of the algorithms.

Peculiarities of producing decorative articles by the method of lost foam casting

This paper investigates the method of lost foam casting performed with consumable patterns. The dependence of the fluidity of the silumin on the polystyrene's characteristics, casting temperature and the pattern's parameters is revealed. Recommendations regarding the application of various polystyrene types for artistic casting are provided.

Parameterized pattern queries

We introduce parameterized pattern queries as a new paradigm to extend traditional pattern expressions over sequence databases. A parameterized pattern is essentially a string made of constant symbols or variables where variables can be matched against any symbol of the input string. Parameterized patterns allow a concise and expressive definition of regular expressions that would be very complex to describe without variables. They can also be used to express additional constraints, to “relax” pattern expressions by allowing more freedom, and finally to cluster patterns in order to minimize the number of symbols’ comparisons.

Model-Driven Constraint Engineering

Precise specification of meta-models is an important prerequisite for the successful application of a model-driven engineering (MDE) process. One means of precise specification are textual constraints. However, the task of constraint de- velopment is time-consuming and error-prone if done manually. In this paper, we present both a methodology and a tool for developing constraints in a systematic way that can be integrated into a CASE tool. Thus, we provide a semi-automated means for integrating constraints into the MDE process. Our approach is based on an extensible library of generic constraint patterns. Con- straint patterns can be combined to create complex constraints and easily parame- terized in a CASE tool. Moreover, we show how these parameterized patterns are transformed into platform-independent or platform-specific constraints by a model transformation.

Periodicity and Repetitions in Parameterized Strings

One of the most beautiful and useful notions in the Mathematical Theory of Strings is that of a Period, i.e., an initial piece of a given string that can generate that string by repeating itself at regular intervals. Periods have an elegant mathematical structure and a wealth of applications [F. Mignosi and A. Restivo, Periodicity, Algebraic Combinatorics on Words, in: M. Lothaire (Ed.), Cambridge University Press, Cambridge, pp. 237-274, 2002]. At the hearth of their theory, there are two Periodicity Lemmas: one due to Lyndon and Schutzenberger [The equation a^M=b^Nc^P in a free group, Michigan Math. J. 9 (1962) 289-298], referred to as the Weak Version, and the other due to Fine and Wilf [Uniqueness theorems for periodic functions, Proc. Amer. Math. Soc. 16 (1965) 109-114]. In this paper, we investigate the notion of periodicity and the closely related one of repetition in connection with parameterized strings as introduced by Baker [Parameterized pattern matching: algorithms and applications, J. Comput. System Sci. 52(1) (1996) 28-42; Parameterized duplication in strings: algorithms and an application to software maintenance, SIAM J. Comput. 26(5) (1997) 1343-1362]. In such strings, the notion of pairwise match or ''equivalence'' of symbols is more relaxed than the usual one, in that it rests on some mapping, rather than identity, of symbols. It seems natural to try and extend notions of periods and periodicities to encompass parameterized strings. However, we know of no previous attempt in this direction. Our preliminary investigation yields results as follows. For periodicity, we get (a) a generalization of the Weak Version of the Periodicity Lemma for parameterized strings, showing that it is essential that the two mappings inducing the periodicity must commute; (b) a proof that an analogous of the Lemma by Fine and Wilf [Uniqueness theorems for periodic functions, Proc. Amer. Math. Soc. 16 (1965) 109-114] cannot hold for parameterized strings, even if the mappings inducing the periodicity ''commute'', in a sense to be specified below; (c) a proof that parameterized strings over an alphabet of at least three letters may have a set of periods which differ from those of any binary string of the same length-whereby the parameterized analog of a classic result by Guibas and Odlyzko [String overlaps, pattern matching, and nontransitive games, J. Combin. Theory Ser. A 30 (1981) 183-208] cannot hold. We also derive necessary and sufficient conditions characterizing parameterized repetitions, which are patterns of length at least twice that of the period, and show how the notion of root differs from the standard case, and highlight some of the implications on extending algorithmic criteria previously adopted for string searching, detection of repetitions and the likes. Finally, as a corollary of our main results, we also show that binary parameterized strings behave much in the same way as non-parameterized ones with respect to periodicity and repetitions, while there is a substantial difference for strings over alphabets of at least three symbols.