2,777 research outputs found
CHARACTERIZATION OF STROKE LESION USING FRACTAL ANALYSIS
Objective: The characterization of stroke lesions is a challenging research issue due to the wide variability in the structure of lesion patterns. The objective of this research work is to characterize the stroke lesion structures using fractal analysis.Methods: To characterize the complex nature of the lesion structures, fractal box counting analysis is presented in this work. Three parameters from fractal dimension (FD) are considered to characterize the nature of the normal and abnormal brain tissues.Results: The experimental results are presented for 15 different datasets. Three different parameters namely FD average, FD deviation, and FDlacunarity are extracted to quantify the properties of the stroke lesion. The observations indicate that there is a significant proportion of separationof feature values between the normal and abnormal brain tissues.Conclusion: This work presents an efficient scheme for characterizing the stroke lesions using fractal parameters. It could be further enhanced by incorporating features extracted from other non-linear techniques.Ă
Randomized Assignment of Jobs to Servers in Heterogeneous Clusters of Shared Servers for Low Delay
We consider the job assignment problem in a multi-server system consisting of
parallel processor sharing servers, categorized into ()
different types according to their processing capacity or speed. Jobs of random
sizes arrive at the system according to a Poisson process with rate . Upon each arrival, a small number of servers from each type is
sampled uniformly at random. The job is then assigned to one of the sampled
servers based on a selection rule. We propose two schemes, each corresponding
to a specific selection rule that aims at reducing the mean sojourn time of
jobs in the system.
We first show that both methods achieve the maximal stability region. We then
analyze the system operating under the proposed schemes as which
corresponds to the mean field. Our results show that asymptotic independence
among servers holds even when is finite and exchangeability holds only
within servers of the same type. We further establish the existence and
uniqueness of stationary solution of the mean field and show that the tail
distribution of server occupancy decays doubly exponentially for each server
type. When the estimates of arrival rates are not available, the proposed
schemes offer simpler alternatives to achieving lower mean sojourn time of
jobs, as shown by our numerical studies
A Study of Erode Tamilanpanâs âVanakkam Valluva Noolâ
In Erode Tamilanbanâs âVanakkam Valluvaâ poetry, the symbolism of poetic virtues can be found in the poem âAgamum Puramum: Andrum Indrumâ (Inside and Out, then and now), the analogy can be seen in the poem âAppothu Ketpenâ (I will ask then), and in the poem, âVina-Vidaiâ (Quiz style) can also be found in the poem âEttaavathu Seerâ (Eighth Syllable). This article explores the trend of modernizing antiquity in âNoveltyâ, the title â God whos has become a Prisonerâ even though God is released from the temple people still hold him captive, on the topic âThe need for loveâ that love is necessary to overcome caste and religion differences and promote equality, the impact of family relationships in the âMemory of the Motherâ, Life is to give in âLife is for givingâ, the social disorder that is caused by drugs titled as 'Social Disgrace' in a satirical sense, and the Questions asked by prostitutes to Valluvar to ensure equality between men and women in âUnrestrained Womenâ
Universal lossless source coding with the Burrows Wheeler transform
The Burrows Wheeler transform (1994) is a reversible sequence transformation used in a variety of practical lossless source-coding algorithms. In each, the BWT is followed by a lossless source code that attempts to exploit the natural ordering of the BWT coefficients. BWT-based compression schemes are widely touted as low-complexity algorithms giving lossless coding rates better than those of the Ziv-Lempel codes (commonly known as LZ'77 and LZ'78) and almost as good as those achieved by prediction by partial matching (PPM) algorithms. To date, the coding performance claims have been made primarily on the basis of experimental results. This work gives a theoretical evaluation of BWT-based coding. The main results of this theoretical evaluation include: (1) statistical characterizations of the BWT output on both finite strings and sequences of length n â â, (2) a variety of very simple new techniques for BWT-based lossless source coding, and (3) proofs of the universality and bounds on the rates of convergence of both new and existing BWT-based codes for finite-memory and stationary ergodic sources. The end result is a theoretical justification and validation of the experimentally derived conclusions: BWT-based lossless source codes achieve universal lossless coding performance that converges to the optimal coding performance more quickly than the rate of convergence observed in Ziv-Lempel style codes and, for some BWT-based codes, within a constant factor of the optimal rate of convergence for finite-memory source
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