Search results for " algorithm"
showing 10 items of 2538 documents
Optimizing diagnostic algorithms to advance Hepatitis C elimination in Italy: A cost effectiveness evaluation
2021
Objectives: Optimized diagnostic algorithms to detect active infections are crucial to achieving HCV elimination. We evaluated the cost effectiveness and sustainability of different algorithms for HCV active infection diagnosis, in a context of a high endemic country for HCV infection. Methods: A Markov disease progression model, simulating six diagnostic algorithms in the birth cohort 1969‐1989 over a 10‐year horizon from a healthcare perspective was used. Conventionally diagnosis of active HCV infection is through detection of antibodies (HCV‐Ab) detection followed by HCV‐RNA or HCV core antigen (HCV‐Ag) confirmatory testing either on a second sample or by same sample reflex testing. The …
A Decision-Tree Approach to Assist in Forecasting the Outcomes of the Neonatal Brain Injury
2021
Neonatal brain injury or neonatal encephalopathy (NE) is a significant morbidity and mortality factor in preterm and full-term newborns. NE has an incidence in the range of 2.5 to 3.5 per 1000 live births carrying a considerable burden for neurological outcomes such as epilepsy, cerebral palsy, cognitive impairments, and hydrocephaly. Many scoring systems based on different risk factor combinations in regression models have been proposed to predict abnormal outcomes. Birthweight, gestational age, Apgar scores, pH, ultrasound and MRI biomarkers, seizures onset, EEG pattern, and seizure duration were the most referred predictors in the literature. Our study proposes a decision-tree approach b…
Italian consensus recommendations for a biomarker‐based aetiological diagnosis in mild cognitive impairment patients
2019
Background and purpose: Biomarkers support the aetiological diagnosis of neurocognitive disorders in vivo. Incomplete evidence is available to drive clinical decisions; available diagnostic algorithms are generic and not very helpful in clinical practice. The aim was to develop a biomarker-based diagnostic algorithm for mild cognitive impairment patients, leveraging on knowledge from recognized national experts. Methods: With a Delphi procedure, experienced clinicians making variable use of biomarkers in clinical practice and representing five Italian scientific societies (neurology – Società Italiana di Neurologia per le Demenze; neuroradiology – Associazione Italiana di Neuroradiologia; b…
Two Simple Constructive algorithms for the Distributed Assembly Permutation Flowshop Scheduling Problem
2014
Nowadays, it is necessary to improve the management of complex supply chains which are often composed of multi-plant facilities. This paper proposes a Distributed Assembly Permutation Flowshop Scheduling Problem (DAPFSP). This problem is a generalization of the Distributed Permutation Flowshop Scheduling Problem (DPFSP) presented by Naderi and Ruiz (Comput Oper Res, 37(4):754–768, 2010). The first stage of the DAPFSP is composed of f identical production factories. Each center is a flowshop that produces jobs that have to be assembled into final products in a second assembly stage. The objective is to minimize the makespan. Two simple constructive algorithms are proposed to solve the proble…
Transmission of Genetic Properties in Permutation Problems: Study of Lehmer Code and Inversion Table Encoding
2021
Solution encoding describes the way decision variables are represented. In the case of permutation problems, the classical encoding should ensure that there are no duplicates. During crossover operations, repairs may be carried out to correct or avoid repetitions. The use of indirect encoding aims to define bijections between the classical permutation and a different representation of the decision variables. These encodings are not sensitive to duplicates. However, they lead to a loss of genetic properties during crossbreeding. This paper proposes a study of the impact of this loss both in the space of decision variables and in that of fitness values. We consider two indirect encoding: the …
Scatter Search vs. Genetic Algorithms
2005
The purpose of this work is to compare the performance of a scatter search (SS) implementation and an implementation of a genetic algorithm (GA) in the context of searching for optimal solutions to permutation problems. Scatter search and genetic algorithms are members of the evolutionary computation family. That is, they are both based on maintaining a population of solutions for the purpose of generating new trial solutions. Our computational experiments with four well-known permutation problems reveal that in general a GA with local search outperforms one without it. Using the same problem instances, we observed that our specific scatter search implementation found solutions of a higher …
Multi-system machine translation using online APIs for English-Latvian
2015
This paper describes a hybrid machine translation (HMT) system that employs several online MT system application program interfaces (APIs) forming a MultiSystem Machine Translation (MSMT) approach. The goal is to improve the automated translation of English – Latvian texts over each of the individual MT APIs. The selection of the best hypothesis translation is done by calculating the perplexity for each hypothesis. Experiment results show a slight improvement of BLEU score and WER (word error rate).
The stability of genetic variance?covariance matrix in the presence of selection
2007
Quantitative genetics provides one of the most important frameworks in which evolutionary biology and evolution can be studied. The primary goals of this field of study include the attempts to understand the history of selection that has resulted in the multiple phenotypic traits we observe today, and to predict the future trajectory of the multiple traits. Within quantitative genetics it is the genetic variance–covariance matrix G which summarizes the additive genetic variation of multiple traits and the genetic covariances between the traits, together with selection that control the direction and rate of evolution. The product of these two elements determine the response to selection from…
Scattering function of semiflexible polymer chains under good solvent conditions
2012
Using the pruned-enriched Rosenbluth Monte Carlo algorithm, the scattering functions of semiflexible macromolecules in dilute solution under good solvent conditions are estimated both in $d=2$ and $d=3$ dimensions, considering also the effect of stretching forces. Using self-avoiding walks of up to $N = 25600$ steps on the square and simple cubic lattices, variable chain stiffness is modeled by introducing an energy penalty $\epsilon_b$ for chain bending; varying $q_b=\exp (- \epsilon_b/k_BT)$ from $q_b=1$ (completely flexible chains) to $q_b = 0.005$, the persistence length can be varied over two orders of magnitude. For unstretched semiflexible chains we test the applicability of the Krat…
Selektionstheorie und Rassenbildung beim Menschen
1952
So far, the applications of the theory of selection to human race formation have primarily considered the selective quality of individual race characters which are preferred by classification. However only few physiologically important race characters have been found to have an evident selective advantage. It is the climate laws, however, that prompt the assumption that selection will take place according to differences of vitality and fertility under certain climatic conditions and that the visible race characters are but incidental effects of pleiotropic gene. It also appears that, in contrast to selection, mutability must be given more consideration to-day than before. For instance the e…