Search results for "data structure"
showing 10 items of 441 documents
Morphological Enhancement and Triangular Matching for Fingerprint Recognition
2008
Among the principal problems for realizing a robust Automated Fingerprint Identification System (AFIS) there are the images quality and matching algorithms. In this paper a fingerprint enhancement algorithm based on morphological filter and a triangular matching are introduced. The enhancement phase is based on tree steps: directional decomposition, morphological filter and composition. For the matching phase a global transformation to overcame the effects of rotation, displacement and deformation between acquired and stored fingerprint is performed using the number of similar triangular, having fingerprint minutiae as vertexes. The performance of the proposed approach has been evaluated on…
Checkpointing Workflows for Fail-Stop Errors
2017
International audience; We consider the problem of orchestrating the exe- cution of workflow applications structured as Directed Acyclic Graphs (DAGs) on parallel computing platforms that are subject to fail-stop failures. The objective is to minimize expected overall execution time, or makespan. A solution to this problem consists of a schedule of the workflow tasks on the available processors and of a decision of which application data to checkpoint to stable storage, so as to mitigate the impact of processor failures. For general DAGs this problem is hopelessly intractable. In fact, given a solution, computing its expected makespan is still a difficult problem. To address this challenge,…
Multi-pass execution of functional logic programs
1994
An operational semantics for functional logic programs is presented. In such programs functional terms provide for reduction of expressions, provided that they ground. The semantics is based on multi-pass evaluation techniques originally developed for attribute grammars. Program execution is divided into two phases: (1) construction of an incomplete proof tree, and (2) its decoration into a complete proof tree. The construction phase applies a modified SLD-resolution scheme, and the decoration phase a partial (multi-pass) traversal over the tree. The phase partition is generated by static analysis where data dependencies are extracted for the functional elements of the program. The method g…
Tree Structured Self-Organizing Maps
1999
Publisher Summary This chapter provides an overview of the tree structured self-organizing maps (TS-SOM). It was originally intended as a fast implementation of the self-organizing map (SOM). The chapter explains that TS-SOM is a constructive smoother for a class of dimension reduction problems. There is a well known relation between self-organizing maps and principal curves. Unfortunately in most presentations it is derived by simple reasoning, avoiding the mathematical statement of the problem, which is essential to understand how efficient SOM implementations can be constructed. In this chapter, SOM is derived as a numerical solution of a generic model in a continuous domain, which diffe…
A Parallel Implementation of the Tree-Structured Self-Organizing Map
2002
This paper presents how Self-Organizing Maps (SOMs)can be trained efficiently using several, simultaneously executing threads on a shared memory Symmetric MultiProcessing (SMP)computer. The training method is a batch version of the Tree-Structured Self-Organizing Map. We note that SMP type of parallel training is very useful for large data sets obtained from nature, the process industry or large document collections, since we do not encounter similar model size limitations as with hardware SOM implementations.
Fully Dynamic Evaluation of Sequence Pair
2013
In the electronic design automation field, as well as in other areas, problem instances and solutions are often subject to discrete changes. The foundational significance of efficient updates of the criterion value after dynamic updates, instead of recomputing it from scratch each time, has attracted a lot of research. In this paper, motivated by the significance of the sequence pair (SP) representation for floorplanning, we develop a fully dynamic algorithm of SP evaluation, that efficiently updates a criterion value after insertions and deletions of SP elements and after modifications of element weights. Our result is based on a new data structure for the predecessor problem, which mainta…
Lightweight algorithms for constructing and inverting the BWT of string collections
2013
Recent progress in the field of \{DNA\} sequencing motivates us to consider the problem of computing the Burrows‚ÄìWheeler transform (BWT) of a collection of strings. A human genome sequencing experiment might yield a billion or more sequences, each 100 characters in length. Such a dataset can now be generated in just a few days on a single sequencing machine. Many algorithms and data structures for compression and indexing of text have the \{BWT\} at their heart, and it would be of great interest to explore their applications to sequence collections such as these. However, computing the \{BWT\} for 100 billion characters or more of data remains a computational challenge. In this work we ad…
Datamining: Pemanfaatan Algoritma Apriori dalam Menganalisa Pola-Pola Transaksi yang Terjadi
2012
This paper will be described about implementation and analysis of the well-known apriori algorithm, which is called Market Basket Analysis (MBA) in data mining. This algorithm is widely used to predict the relation among market basket in the huge amount of database. This algorithm is based on the concept of a prefix tree. There are several ways to organize the nodes of such a tree, to encode the items, and to organize the transactions, which may be used in order to minimize the time needed to find the frequent itemsets as well as to reduce the amount of memory needed to store the counters. The rules produced will be used by management of supermarket to organize the items set to increase the…
Spectral properties of correlation matrices for some hierarchically nested factor models
2007
We show that spectral methods, such as Principal Component Analysis and Random Matrix Theory, are unable to reveal the hierarchical (or nested) structure of a set of mutivariate data. We consider the method introduced in M. Tumminello et al., EPL 78, 30006 (2007) to associate a hierarchical factor model with a set of data by making use of clustering algorithms. This is done by proving the existence of a bijective correspondence between a hierarchical tree and a factor model.
The effect of two growth bio regulators on the physiological, phenological and qualitative parameters of peach tree production
2021
The risk that plants have not accumulated sufficient chilling units (CU) and the economic interest in anticipating flowering have led to growing scientific interest in the use of bio plant regulators to stop dormant peach trees in farms that use agronomic particulates in precision farming protocols. The trials were conducted in 2016 and 2017, on peach trees of the cultivar Maycrest, grown in a commercial orchard located in Metaponto, Basilicata (Southern Italy). A complete randomization experimental scheme was adopted; three theses (control, Fast and Regular® and Asy 23) and two different intervention periods have been provided for, the doses used have been 500g/hl for Fast & Regular® a…