957 resultados para gravitational search algorithm


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The objective of this thesis is to develop and generalize further the differential evolution based data classification method. For many years, evolutionary algorithms have been successfully applied to many classification tasks. Evolution algorithms are population based, stochastic search algorithms that mimic natural selection and genetics. Differential evolution is an evolutionary algorithm that has gained popularity because of its simplicity and good observed performance. In this thesis a differential evolution classifier with pool of distances is proposed, demonstrated and initially evaluated. The differential evolution classifier is a nearest prototype vector based classifier that applies a global optimization algorithm, differential evolution, to determine the optimal values for all free parameters of the classifier model during the training phase of the classifier. The differential evolution classifier applies the individually optimized distance measure for each new data set to be classified is generalized to cover a pool of distances. Instead of optimizing a single distance measure for the given data set, the selection of the optimal distance measure from a predefined pool of alternative measures is attempted systematically and automatically. Furthermore, instead of only selecting the optimal distance measure from a set of alternatives, an attempt is made to optimize the values of the possible control parameters related with the selected distance measure. Specifically, a pool of alternative distance measures is first created and then the differential evolution algorithm is applied to select the optimal distance measure that yields the highest classification accuracy with the current data. After determining the optimal distance measures for the given data set together with their optimal parameters, all determined distance measures are aggregated to form a single total distance measure. The total distance measure is applied to the final classification decisions. The actual classification process is still based on the nearest prototype vector principle; a sample belongs to the class represented by the nearest prototype vector when measured with the optimized total distance measure. During the training process the differential evolution algorithm determines the optimal class vectors, selects optimal distance metrics, and determines the optimal values for the free parameters of each selected distance measure. The results obtained with the above method confirm that the choice of distance measure is one of the most crucial factors for obtaining higher classification accuracy. The results also demonstrate that it is possible to build a classifier that is able to select the optimal distance measure for the given data set automatically and systematically. After finding optimal distance measures together with optimal parameters from the particular distance measure results are then aggregated to form a total distance, which will be used to form the deviation between the class vectors and samples and thus classify the samples. This thesis also discusses two types of aggregation operators, namely, ordered weighted averaging (OWA) based multi-distances and generalized ordered weighted averaging (GOWA). These aggregation operators were applied in this work to the aggregation of the normalized distance values. The results demonstrate that a proper combination of aggregation operator and weight generation scheme play an important role in obtaining good classification accuracy. The main outcomes of the work are the six new generalized versions of previous method called differential evolution classifier. All these DE classifier demonstrated good results in the classification tasks.

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Calves born persistently infected with non-cytopathic bovine viral diarrhea virus (ncpBVDV) frequently develop a fatal gastroenteric illness called mucosal disease. Both the original virus (ncpBVDV) and an antigenically identical but cytopathic virus (cpBVDV) can be isolated from animals affected by mucosal disease. Cytopathic BVDVs originate from their ncp counterparts by diverse genetic mechanisms, all leading to the expression of the non-structural polypeptide NS3 as a discrete protein. In contrast, ncpBVDVs express only the large precursor polypeptide, NS2-3, which contains the NS3 sequence within its carboxy-terminal half. We report here the investigation of the mechanism leading to NS3 expression in 41 cpBVDV isolates. An RT-PCR strategy was employed to detect RNA insertions within the NS2-3 gene and/or duplication of the NS3 gene, two common mechanisms of NS3 expression. RT-PCR amplification revealed insertions in the NS2-3 gene of three cp isolates, with the inserts being similar in size to that present in the cpBVDV NADL strain. Sequencing of one such insert revealed a 296-nucleotide sequence with a central core of 270 nucleotides coding for an amino acid sequence highly homologous (98%) to the NADL insert, a sequence corresponding to part of the cellular J-Domain gene. One cpBVDV isolate contained a duplication of the NS3 gene downstream from the original locus. In contrast, no detectable NS2-3 insertions or NS3 gene duplications were observed in the genome of 37 cp isolates. These results demonstrate that processing of NS2-3 without bulk mRNA insertions or NS3 gene duplications seems to be a frequent mechanism leading to NS3 expression and BVDV cytopathology.

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The thesis examines the phenomenon most commonly known as “ayahuasca tourism” – i.e. the practice of westerners traveling to South America and partaking in ceremonies in which a powerful entheogenic brew, ayahuasca, is consumed. While this popular phenomenon has been steadily increasing during the last decades, it has, however, been insufficiently studied by scholars. An important question which has not been properly addressed in earlier studies is how ayahuasca tourism relates to the wider occurrence of travel and how it should be perceived with reference to the theoretical frameworks on the subject of travel. Drawing on theories regarding pilgrimage and tourism, the main purpose of this thesis is to examine the relationship between ayahuasca tourism and the broader spectrum of travel. In particular, the study tests the designations “pilgrimage”, “religious tourism” and “spiritual tourism” with reference to ayahuasca tourism. Utilizing earlier literature as well as ayahuasca tourists‟ reports obtained from an Internet forum as a basis for analysis, I search for a suitable terminology to be used for the phenomenon. The study lays special emphasis on the protagonists‟ motivations, experiences and outcomes in order to take note of various aspects of the wide-ranging occurrence of ayahuasca tourism. Key findings indicate that ayahuasca tourism is best understood as a combination of pilgrimage and tourism. On the basis of the analysis I argue that ayahuasca tourism should be labeled as “pilgrimage” and/or “spiritual tourism”, and the tourists respectively as “pilgrims” and/or “spiritual tourists”. The category of “religious tourism/tourist”, on the other hand, turns out to be an inappropriate designation when describing the phenomenon. In general, through my study I show that the results are consistent with the present trend in the study of travel to perceive pilgrimage and tourism as theoretically similar phenomena. The study of ayahuasca tourism serves thus as living proof of contemporary travel, in which the categories of pilgrimage and tourism are often indistinguishable. I suggest that ayahuasca tourism is by no means exceptional on this point, but can rather be used as an illustration of modern travel forms on a general level. Thus, the present study does not only add to the research of ayahuasca tourism, but also provides additional insights into the study of travel.

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Proliferatiivinen verrukoottinen leukoplakia (PVL) esiintyy yhtenä laajana tai useampana verrukoottisena, valkoisena muutoksena suun limakalvoilla. PVL on aggressiivinen limakalvomuutos, joka ei usein vastaa hoitoihin, uusii herkästi ja sillä on muita leukoplakioita suurempi pahanlaatuistumistaipumus. Tutkimuksen tarkoitus on lisätä tietoa PVL:sta ja sen ilmentymisestä ja kehittymisestä sekä arvioida kriittisesti PVL:n diagnostiikkaa. Systemaattinen kirjallisuuskatsaus suoritettiin etsimällä Pubmed-tietokannan kirjallisuushaulla kaikki englannin kielellä raportoidut ja vertaisarvioidut PVL- potilastapaukset 2000 – 2013. PVL voi histologisesti esiintyä myös verrukoottisena hyperplasiana (VH), joten myös nämä tapaukset sisällytettiin aineistoon. Kaikkiaan 54 artikkelia täytti sisäänottokriteerit. Näissä oli yhteensä 388 PVL- ja 848 VH-tapausta. Lisäksi kerättiin kaikki Turun yliopiston hammaslääketieteen laitoksen suupatologian osastolla histologisesti diagnosoidut vastaavat suun VH-muutokset 2000 – 2013. Kirjallisuudesta havaittiin, että PVL esiintyi useammin naisilla (2,2 : 1), kun taas VH esiintyi useammin miehillä (1 : 3,8). Tupakointi ei näyttänyt liittyvän PVL:aan (30 %), kun taas VH:aan se näytti selkeämmin liittyvän (83 %). PVL:n yleisin sijainti oli ikenellä (59 %) ja suurin osa VH-muutoksista esiintyi posken limakalvolla (51 %). PVL-potilaista 47 %:lla ja VH-potilaista 5 %:lla todettiin seurannassa pahanlaatuinen kasvain. Turun yliopiston suupatologian osastolla diagnosoituja VH-tapauksia oli 13 vuoden aikana 29. Naisten osuus sairastuneista oli suurempi kuin miesten (1,4 : 1). Muutokset esiintyivät yleisimmin kielen limakalvolla (48 %) ja poskessa (34 %). Yhdessä tapauksessa kehittyi pahanlaatuinen kasvain (3 %). Tutkimuksessa todettiin, että PVL- ja VH-muutokset poikkeavat toisistaan sukupuolijakauman, tupakoinnin ja pahanlaatuistumisen osalta. Ongelmana katsauksessa olivat tietojen puutteellisuus ja raportoinnin heterogeenisyys kirjallisuudessa. PVL- ja VH-tutkimuksessa tulisikin panostaa yhteneviin diagnostisiin kriteereihin, jotta materiaalit olisivat vertailukelpoisia. Potilaan kannalta PVL:n ja VH:n varhainen diagnosointi ja huolellinen seuranta ovat olennaisen tärkeitä asioita.

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Individual circadian clocks entrain differently to environmental cycles (zeitgebers, e.g., light and darkness), earlier or later within the day, leading to different chronotypes. In human populations, the distribution of chronotypes forms a bell-shaped curve, with the extreme early and late types _ larks and owls, respectively _ at its ends. Human chronotype, which can be assessed by the timing of an individual's sleep-wake cycle, is partly influenced by genetic factors - known from animal experimentation. Here, we review population genetic studies which have used a questionnaire probing individual daily timing preference for associations with polymorphisms in clock genes. We discuss their inherent limitations and suggest an alternative approach combining a short questionnaire (Munich ChronoType Questionnaire, MCTQ), which assesses chronotype in a quantitative manner, with a genome-wide analysis (GWA). The advantages of these methods in comparison to assessing time-of-day preferences and single nucleotide polymorphism genotyping are discussed. In the future, global studies of chronotype using the MCTQ and GWA may also contribute to understanding the influence of seasons, latitude (e.g., different photoperiods), and climate on allele frequencies and chronotype distribution in different populations.

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Chronic hepatitis B (HBV) and C (HCV) virus infections are the most important factors associated with hepatocellular carcinoma (HCC), but tumor prognosis remains poor due to the lack of diagnostic biomarkers. In order to identify novel diagnostic markers and therapeutic targets, the gene expression profile associated with viral and non-viral HCC was assessed in 9 tumor samples by oligo-microarrays. The differentially expressed genes were examined using a z-score and KEGG pathway for the search of ontological biological processes. We selected a non-redundant set of 15 genes with the lowest P value for clustering samples into three groups using the non-supervised algorithm k-means. Fisher’s linear discriminant analysis was then applied in an exhaustive search of trios of genes that could be used to build classifiers for class distinction. Different transcriptional levels of genes were identified in HCC of different etiologies and from different HCC samples. When comparing HBV-HCC vs HCV-HCC, HBV-HCC/HCV-HCC vs non-viral (NV)-HCC, HBC-HCC vs NV-HCC, and HCV-HCC vs NV-HCC of the 58 non-redundant differentially expressed genes, only 6 genes (IKBKβ, CREBBP, WNT10B, PRDX6, ITGAV, and IFNAR1) were found to be associated with hepatic carcinogenesis. By combining trios, classifiers could be generated, which correctly classified 100% of the samples. This expression profiling may provide a useful tool for research into the pathophysiology of HCC. A detailed understanding of how these distinct genes are involved in molecular pathways is of fundamental importance to the development of effective HCC chemoprevention and treatment.

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The SEARCH-RIO study prospectively investigated electrocardiogram (ECG)-derived variables in chronic Chagas disease (CCD) as predictors of cardiac death and new onset ventricular tachycardia (VT). Cardiac arrhythmia is a major cause of death in CCD, and electrical markers may play a significant role in risk stratification. One hundred clinically stable outpatients with CCD were enrolled in this study. They initially underwent a 12-lead resting ECG, signal-averaged ECG, and 24-h ambulatory ECG. Abnormal Q-waves, filtered QRS duration, intraventricular electrical transients (IVET), 24-h standard deviation of normal RR intervals (SDNN), and VT were assessed. Echocardiograms assessed left ventricular ejection fraction. Predictors of cardiac death and new onset VT were identified in a Cox proportional hazard model. During a mean follow-up of 95.3 months, 36 patients had adverse events: 22 new onset VT (mean±SD, 18.4±4‰/year) and 20 deaths (26.4±1.8‰/year). In multivariate analysis, only Q-wave (hazard ratio, HR=6.7; P<0.001), VT (HR=5.3; P<0.001), SDNN<100 ms (HR=4.0; P=0.006), and IVET+ (HR=3.0; P=0.04) were independent predictors of the composite endpoint of cardiac death and new onset VT. A prognostic score was developed by weighting points proportional to beta coefficients and summing-up: Q-wave=2; VT=2; SDNN<100 ms=1; IVET+=1. Receiver operating characteristic curve analysis optimized the cutoff value at >1. In 10,000 bootstraps, the C-statistic of this novel score was non-inferior to a previously validated (Rassi) score (0.89±0.03 and 0.80±0.05, respectively; test for non-inferiority: P<0.001). In CCD, surface ECG-derived variables are predictors of cardiac death and new onset VT.

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The aim of this thesis is to propose a novel control method for teleoperated electrohydraulic servo systems that implements a reliable haptic sense between the human and manipulator interaction, and an ideal position control between the manipulator and the task environment interaction. The proposed method has the characteristics of a universal technique independent of the actual control algorithm and it can be applied with other suitable control methods as a real-time control strategy. The motivation to develop this control method is the necessity for a reliable real-time controller for teleoperated electrohydraulic servo systems that provides highly accurate position control based on joystick inputs with haptic capabilities. The contribution of the research is that the proposed control method combines a directed random search method and a real-time simulation to develop an intelligent controller in which each generation of parameters is tested on-line by the real-time simulator before being applied to the real process. The controller was evaluated on a hydraulic position servo system. The simulator of the hydraulic system was built based on Markov chain Monte Carlo (MCMC) method. A Particle Swarm Optimization algorithm combined with the foraging behavior of E. coli bacteria was utilized as the directed random search engine. The control strategy allows the operator to be plugged into the work environment dynamically and kinetically. This helps to ensure the system has haptic sense with high stability, without abstracting away the dynamics of the hydraulic system. The new control algorithm provides asymptotically exact tracking of both, the position and the contact force. In addition, this research proposes a novel method for re-calibration of multi-axis force/torque sensors. The method makes several improvements to traditional methods. It can be used without dismantling the sensor from its application and it requires smaller number of standard loads for calibration. It is also more cost efficient and faster in comparison to traditional calibration methods. The proposed method was developed in response to re-calibration issues with the force sensors utilized in teleoperated systems. The new approach aimed to avoid dismantling of the sensors from their applications for applying calibration. A major complication with many manipulators is the difficulty accessing them when they operate inside a non-accessible environment; especially if those environments are harsh; such as in radioactive areas. The proposed technique is based on design of experiment methodology. It has been successfully applied to different force/torque sensors and this research presents experimental validation of use of the calibration method with one of the force sensors which method has been applied to.

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The genetic and environmental risk factors of vascular cognitive impairment are still largely unknown. This thesis aimed to assess the genetic background of two clinically similar familial small vessel diseases (SVD), CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy) and Swedish hMID (hereditary multi-infarct dementia of Swedish type). In the first study, selected genetic modifiers of CADASIL were studied in a homogenous Finnish CADASIL population of 134 patients, all carrying the p.Arg133Cys mutation in NOTCH3. Apolipoprotein E (APOE) genotypes, angiotensinogen (AGT) p.Met268Thr polymorphism and eight NOTCH3 polymorphisms were studied, but no associations between any particular genetic variant and first-ever stroke or migraine were seen. In the second study, smoking, statin medication and physical activity were suggested to be the most profound environmental differences among the monozygotic twins with CADASIL. Swedish hMID was for long misdiagnosed as CADASIL. In the third study, the CADASIL diagnosis in the Swedish hMID family was ruled out on the basis of genetic, radiological and pathological findings, and Swedish hMID was suggested to represent a novel SVD. In the fourth study, the gene defect of Swedish hMID was then sought using whole exome sequencing paired with a linkage analysis. The strongest candidate for the pathogenic mutation was a 3’UTR variant in the COL4A1 gene, but further studies are needed to confirm its functionality. This study provided new information about the genetic background of two inherited SVDs. Profound knowledge about the pathogenic mutations causing familial SVD is also important for correct diagnosis and treatment options.

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This work presents synopsis of efficient strategies used in power managements for achieving the most economical power and energy consumption in multicore systems, FPGA and NoC Platforms. In this work, a practical approach was taken, in an effort to validate the significance of the proposed Adaptive Power Management Algorithm (APMA), proposed for system developed, for this thesis project. This system comprise arithmetic and logic unit, up and down counters, adder, state machine and multiplexer. The essence of carrying this project firstly, is to develop a system that will be used for this power management project. Secondly, to perform area and power synopsis of the system on these various scalable technology platforms, UMC 90nm nanotechnology 1.2v, UMC 90nm nanotechnology 1.32v and UMC 0.18 μmNanotechnology 1.80v, in order to examine the difference in area and power consumption of the system on the platforms. Thirdly, to explore various strategies that can be used to reducing system’s power consumption and to propose an adaptive power management algorithm that can be used to reduce the power consumption of the system. The strategies introduced in this work comprise Dynamic Voltage Frequency Scaling (DVFS) and task parallelism. After the system development, it was run on FPGA board, basically NoC Platforms and on these various technology platforms UMC 90nm nanotechnology1.2v, UMC 90nm nanotechnology 1.32v and UMC180 nm nanotechnology 1.80v, the system synthesis was successfully accomplished, the simulated result analysis shows that the system meets all functional requirements, the power consumption and the area utilization were recorded and analyzed in chapter 7 of this work. This work extensively reviewed various strategies for managing power consumption which were quantitative research works by many researchers and companies, it's a mixture of study analysis and experimented lab works, it condensed and presents the whole basic concepts of power management strategy from quality technical papers.

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The debate on the link between trade rules and rules on exchange rates is raising the attention of experts on international trade law and economics. The main purpose of this paper is to analyze the impacts of exchange rate misalignments on tariffs as applied by the WTO - World Trade Organization. It is divided into five sections: the first one explains the methodology used to determine exchange rate misalignments and also presents its results for Brazil, U.S. and China; the second summarizes the methodology applied to calculate the impacts of exchange rate misalignments on the level of tariff protection through an exercise of "misalignment tariffication"; the third examines the effects of exchange rate variations on tariffs and their consequences for the multilateral trading system; the fourth one creates a methodology to estimate exchange rates against a currency of the World and a proposal to deal with persistent and significant misalignments related to trade rules. The conclusions are present in the last section.

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The dissertation examines the rule of law within the European Union in the theoretical framework of constitutional pluralism. The leading lines of constitutional pluralism are examined with relation to the traditional and prevailing, monistic and hierarchical conceptions on how to perceive legal orders in Europe. The theoretical part offers also historical perspective by highlighting some of the turning points for the Union constitutional legal order in the framework of European integration. The concept of rule of law is examined in legal terms and its meaning to the Union constitutional constellation as a constitutional principle and a common value is observed. The realization of the rule of law at supranational and national level is explored with a view to discover that recent developments in some of the Member States give rise to concern about the viability of the rule of law within the European Union. It is recognized that the inobservance of the rule of law at national level causes a threat to the supranational constitutional legal order. The relationship between the supranational and national legal orders is significant in this respect and therefore particularly the interaction between the Court of Justice of the European Union (hereinafter the ECJ) and the Member States’ (constitutional/supreme) courts takes focus. It is observed that functioning dialogue between the supranational and national courts based on mutual respect and judicial deference is an important prerequisite for the realization of the rule of law within Europe. In order to afford a concrete example, a recent case C-62/14 Gauweiler v Deutscher Bundestag is introduced and analysed in relation to the notorious relationship between the Federal Constitutional Court of Germany and the ECJ. The implications of the ECJ’s decision in Gauweiler v Deutscher Bundestag is assessed with reference to some of the pressing issues of constitutionalism within Europe and some institutional aspects are also brought forward. Lastly, the feasibility of constitutional pluralism as a theoretical setting is measured against the legal reality of today’s Europe and its many constitutions. The hierarchical idea of one ultimate source of power, stemming from the traditional approaches to legal systems, is then assessed with relation to the requirement of the realization of the rule of law within the European Union from the supranational and national point of view.

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This study focuses on teacher practices in publicly funded music schools in Finland. As views on the aims of music education change and broaden, music schools across Europe share the challenge of developing their activities in response. In public and scholarly debate, there have been calls for increased diversity of contents and concepts of teaching. In Finland, the official national curriculum for state-funded music schools builds on the ideal that teaching and learning should create conditions which promote ‘a good relationship to music’. The meaning of this concept has been deliberately left open in order to leave room for dialogue, flexibility, and teacher autonomy. Since what is meant by ‘good’ is not defined in advance, the notion of ‘improving’ practices is also open to discussion. The purpose of the study is to examine these issues from teachers’ point of view by asking what music school teachers aim to accomplish as they develop their practices. Methodologically, the study introduces a suggestion for building empirical research on Alperson’s ‘robust’ praxial approach to music education, a philosophical theory which is strongly committed to practitioner perspectives and musical diversity. A systematic method for analysing music education practices, interpretive practice analysis, is elaborated with support from interpretive research methods originally used in policy analysis. In addition, the research design shows how reflecting conversations (a collaborative approach well-known in Nordic social work) can be fruitfully applied in interpretive research and combined with teacher inquiry. Data have been generated in a collaborative project involving five experienced music school teachers and the researcher. The empirical material includes transcripts from group conversations, data from teacher inquiry conducted within the project, and transcripts from follow-up interviews. The teachers’ aspirations can be understood as strivings to reinforce the connection between musical practices and various forms of human flourishing such that music and flourishing can sustain each other. Examples from their practices show how the word ‘good’ receives its meaning in context. Central among the teachers’ concerns is their hope that students develop a free and sustainable interest in music, often described as inspiration. I propose that ‘good relationships to music’ and ‘inspiration’ can be understood as philosophical mediators which support the transition from an indeterminate ‘interest in music’ towards specific ways in which music can become a (co-)constitutive part of living well in each person’s particular circumstances. Different musical practices emphasise different aspects of what is considered important in music and in human life. Music school teachers consciously balance between a variety of such values. They also make efforts to resist pressure which might threaten the goods they think are most important. Such goods include joy, participation, perseverance, solid musical skills related to specific practices, and a strong sense of vitality. The insights from this study suggest that when teachers are able to create inspiration, they seem to do so by performing complex work which combines musical and educational aims and makes general positive contributions to their students’ lives. Ensuring that teaching and learning in music schools remain as constructive and meaningful as possible for both students and teachers is a demanding task. The study indicates that collaborative, reflective and interdisciplinary work may be helpful as support for development processes on both individual and collective levels of music school teacher practices.