800 resultados para landscape compensation


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This work presents recent results concerning a design methodology used to estimate the positioning deviation for a gantry (Cartesian) manipulator, related mainly to structural elastic deformation of components during operational conditions. The case-study manipulator is classified as gantry type and its basic dimensions are 1,53m x 0,97m x 1,38m. The dimensions used for the calculation of effective workspace due to end-effector path displacement are: 1m x 0,5m x 0,5m. The manipulator is composed by four basic modules defined as module X, module Y, module Z and terminal arm, where is connected the end-effector. Each module controlled axis performs a linear-parabolic positioning movement. The planning path algorithm has the maximum velocity and the total distance as input parameters for a given task. The acceleration and deceleration times are the same. Denavit-Hartemberg parameterization method is used in the manipulator kinematics model. The gantry manipulator can be modeled as four rigid bodies with three degrees-of-freedom in translational movements, connected as an open kinematics chain. Dynamic analysis were performed considering inertial parameters specification such as component mass, inertia and center of gravity position of each module. These parameters are essential for a correct manipulator dynamic modelling, due to multiple possibilities of motion and manipulation of objects with different masses. The dynamic analysis consists of a mathematical modelling of the static and dynamic interactions among the modules. The computation of the structural deformations uses the finite element method (FEM).

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Control of an industrial robot is mainly a problem of dynamics. It includes non-linearities, uncertainties and external perturbations that should be considered in the design of control laws. In this work, two control strategies based on variable structure controllers (VSC) and a PD control algorithm are compared in relation to the tracking errors considering friction. The controller's performances are evaluated by adding an static friction model. Simulations and experimental results show it is possible to diminish tracking errors by using a model based friction compensation scheme. A SCARA robot is used to illustrate the conclusions of this paper.

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Speed, uncertainty and complexity are increasing in the business world all the time. When knowledge and skills become quickly irrelevant, new challenges are set for information technology (IT) education. Meta-learning skills – learning how to learn rapidly - and innovation skills have become more essential than single technologies or other specific issues. The drastic changes in the information and communications technology (ICT) sector have caused a need to reconsider how IT Bachelor education in Universities of Applied Sciences should be organized and employed to cope with the change. The objective of the study was to evaluate how a new approach to IT Bachelor education, the ICT entrepreneurship study path (ICT-ESP) fits IT Bachelor education in a Finnish University of Applied Sciences. This kind of educational arrangement has not been employed elsewhere in the context of IT Bachelor education. The study presents the results of a four-year period during which IT Bachelor education was renewed in a Finnish University of Applied Sciences. The learning environment was organized into an ICT-ESP based on Nonaka’s knowledge theory and Kolb’s experiental learning. The IT students who studied in the ICT-ESP established a cooperative and learned ICT by running their cooperative at the University of Applied Sciences. The students (called team entrepreneurs) studied by reading theory in books and other sources of explicit information, doing projects for their customers, and reflecting in training sessions on what was learnt by doing and by studying the literature. Action research was used as the research strategy in this study. Empirical data was collected via theme-based interviews, direct observation, and participative observation. Grounded theory method was utilized in the data analysis and the theoretical sampling was used to guide the data collection. The context of the University of Applied Sciences provided a good basis for fostering team entrepreneurship. However, the results showed that the employment of the ICT-ESP did not fit into the IT Bachelor education well enough. The ICT-ESP was cognitively too tough for the team entrepreneurs because they had two different set of rules to follow in their studies. The conventional courses engaged lot of energy which should have been spent for professional development in the ICT-ESP. The amount of competencies needed in the ICT-ESP for professional development was greater than those needed for any other ways of studying. The team entrepreneurs needed to develop skills in ICT, leadership and self-leadership, team development and entrepreneurship skills. The entrepreneurship skills included skills on marketing and sales, brand development, productization, and business administration. Considering the three-year time the team entrepreneurs spent in the ICT-ESP, the challenges were remarkable. Changes to the organization of IT Bachelor education are also suggested in the study. At first, it should be admitted that the ICT-ESP produces IT Bachelors with a different set of competencies compared to the conventional way of educating IT Bachelors. Secondly, the number of courses on general topics in mathematics, physics, and languages for team entrepreneurs studying in the ICTESP should be reconsidered and the conventional course-based teaching of the topics should be reorganized to support the team coaching process of the team entrepreneurs with their practiceoriented projects. Third, the upcoming team entrepreneurs should be equipped with relevant information about the ICT-ESP and what it would require in practice to study as a team entrepreneur. Finally, the upcoming team entrepreneurs should be carefully selected before they start in the ICT-ESP to have a possibility to eliminate solo players and those who have a too romantic view of being a team entrepreneur. The results gained in the study provided answers to the original research questions and the objectives of the study were met. Even though the IT degree programme was terminated during the research process, the amount of qualitative data gathered made it possible to justify the interpretations done.

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The main hypothesis for prion diseases proposes that the cellular protein (PrP C) can be altered into a misfolded, ß-sheet-rich isoform, the PrP Sc (from scrapie). The formation of this abnormal isoform then triggers the transmissible spongiform encephalopathies. Here, we discuss the use of high pressure as a tool to investigate this structural transition and to populate possible intermediates in the folding/unfolding pathway of the prion protein. The latest findings on the application of high pressure to the cellular prion protein and to the scrapie PrP forms will be summarized in this review, which focuses on the energetic and volumetric properties of prion folding and conversion.

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Reciprocal selection between interacting species is a major driver of biodiversity at both the genetic and the species level. This reciprocal selection, or coevolution, has led to the diversification of two highly diverse and abundant groups of organisms, flowering plants and their insect herbivores. In heterogeneous environments, the outcome of coevolved species interactions is influenced by the surrounding community and/or the abiotic environment. The process of adaptation allows species to adapt to their local conditions and to local populations of interacting species. However, adaptation can be disrupted or slowed down by an absence of genetic variation or by increased inbreeding, together with the following inbreeding depression, both of which are common in small and isolated populations that occur in fragmented environments. I studied the interaction between a long-lived plant Vincetoxicum hirundinaria and its specialist herbivore Abrostola asclepiadis in the southwestern archipelago of Finland. I focused on mutual local adaptation of plants and herbivores, which is a demonstration of reciprocal selection between species, a prerequisite for coevolution. I then proceeded to investigate the processes that could potentially hamper local adaptation, or species interaction in general, when the population size is small. I did this by examining how inbreeding of both plants and herbivores affects traits that are important for interaction, as well as among-population variation in the effects of inbreeding. In addition to bi-parental inbreeding, in plants inbreeding can arise from self-fertilization which has important implications for mating system evolution. I found that local adaptation of the plant to its herbivores varied among populations. Local adaptation of the herbivore varied among populations and years, being weaker in populations that were most connected. Inbreeding caused inbreeding depression in both plants and herbivores. In some populations inbreeding depression in herbivore biomass was stronger in herbivores feeding on inbred plants than in those feeding on outbred ones. For plants it was the other way around: inbreeding depression in anti-herbivore resistance decreased when the herbivores were inbred. Underlying some of the among-population variation in the effects of inbreeding is variation in plant phenolic compounds. However, variation in the modification of phenolic compounds in the digestive tract of the herbivore did not explain the inbreeding depression in herbivore biomass. Finally, adult herbivores had a preference for outbred host plants for egg deposition, and herbivore inbreeding had a positive effect on egg survival when the eggs were exposed to predators and parasitoids. These results suggest that plants and herbivores indeed exert reciprocal selection, as demonstrated by the significant local adaptation of V. hirundinaria and A. asclepiadis to one another. The most significant cause of disruption of the local adaptation of herbivore populations was population connectivity, and thus probably gene flow. In plants local adaptation tended to increase with increasing genetic variation. Whether or not inbreeding depression occurred varied according to the life-history stage of the herbivore and/or the plant trait in question. In addition, the effects of inbreeding strongly depended on the population. Taken together, inbreeding modified plant-herbivore interactions at several different levels, and can thus affect the strength of reciprocal selection between species. Thus inbreeding has the potential to affect the outcome of coevolution.

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Moisture equilibrium data of mango pulp were determined using the static gravimetric method. Adsorption and desorption isotherms were obtained in the range of 30-70 ºC, to water activities (a w) from 0.02 to 0.97. The application of the GAB model to the experimental results, using direct nonlinear regression analysis, provided agreement between experimental and calculated values. The net isosteric heat of sorption was estimated from equilibrium sorption data, using the Clausius-Clapeyron equation. Isosteric heats of sorption were found to increase with increasing temperature and could be well adjusted by an exponential relationship. The enthalpy-entropy compensation theory was applied to sorption isotherms and plots of deltaH versus deltaS provided the isokinetic temperatures, indicating an enthalpy controlled sorption process.

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This study aimed at verifying the influence of the seasonality and landscape of the place of apiaries in the production and physicochemical quality of propolis produced in Cáceres-MT. Within August/2006 and July/2007 twenty-three propolis samples were collected monthly. The physicochemical quality of propolis was determined by the characteristic: loss by drying, wax, mechanical mass, oxidation activity, dry extract, flavonoids and total phenolics. The production of propolis was analyzed through correlation with seasonality (dry and wet). The same statistic model was used to correlate the production with the landscape (highland and flood plain). For each physicochemical characteristic were used statistic model of correlation described for the production of propolis. The seasonality did not influence on propolis production and on physicochemical quality. The landscape did not influence on propolis production and physicochemical quality loss by drying and mechanical mass, however, it determined the physicochemical quality for wax (x=22.44%), oxidation activity (x=9.73''), dry extract (x=22.31%), flavonoids (x=1.94%) and total phenolics (x=0.02%) in the highland of the Pantanal of Cáceres. This way it concludes that the production and physicochemical quality of propolis were not influenced by seasonality. The landscape influenced positively on physicochemical quality of propolis in the highland of the Pantanal of Cáceres.

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Kaikkien kansalaisten ja yritysten, jotka kärsivät vahinkoa Euroopan Unionin kilpailusääntöjen (SEUT 101 ja 102 artiklan) rikkomisen vuoksi, on voitava vaatia korvauksia vahingon aiheuttaneelta osapuolelta. Euroopan unionin tuomioistuin on ratkaisuillaan Courage ja Manfredi vahvistanut vahinkoa kärsineen oikeuden saada korvausta kärsimästään vahingosta. Suomessa kilpailuoikeudellista vahingonkorvausta koskeva oikeuskäytäntö on ollut vähäistä, vaikkakin viime aikoina on annettu muutama merkittävä vahingonkorvausratkaisu, näistä kenties tunnetuimpana asvalttikartelliratkaisu. Kilpailuoikeuden rikkomisesta vahinkoa kärsineet saavat kuitenkin vain harvoin korvausta kärsimästään vahingosta, mikä on ollut seurausta erilaisista lainsäädännöllisistä ja menettelyistä johtuvista esteistä jäsenvaltioiden säännöissä. Komission pitkään kestänyt lainsäädäntöhanke EU:n kilpailuoikeuden täytäntöönpanojärjestelmän selkeyttämiseksi päättyi marraskuussa 2014, kun Euroopan parlamentin ja neuvoston direktiivi tietyistä säännöistä, joita sovelletaan jäsenvaltioiden ja Euroopan unionin kilpailuoikeuden rikkomisen johdosta kansallisen lainsäädännön nojalla nostettuihin vahingonkorvauskanteisiin (2014/104/ EU) hyväksyttiin. Direktiivi julkaistiin Euroopan unionin virallisessa lehdessä 5. joulukuuta 2014, ja jäsenvaltioilla on 27.12.2016 asti aikaa implementoida direktiivi osaksi kansallista lainsäädäntöä. Direktiivin tavoitteena on EU:n kilpailusääntöjen tehokas täytäntöönpano sekä kilpailuoikeuden julkisoikeudellisen ja yksityisoikeudellisen täytäntöönpanon selkeyttäminen. Lisäksi direktiivi pyrkii varmistamaan, että vahingonkärsijät voivat saada täyden korvauksen kärsimästään vahingosta, sekä poistamaan esteitä ja pienentämään kustannuksia vahingon todistamisessa, samalla harmonisoiden eri jäsenmaissa toimivien yritysten oikeussuojan tasoa. Tarkastelen pro gradu –tutkielmassani kilpailuoikeudellisen vahingonkorvauksen kehitystä sekä uuden EU:n vahingonkorvausdirektiivin vaikutuksia erityisesti vahingonkärsijän näkökulmasta, eli sitä kuinka direktiivi vaikuttaa vahingonkärsijän mahdollisuuteen saada korvausta kärsimästään vahingosta, joka johtuu EU:n kilpailusääntöjen rikkomisesta. Lisäksi tarkastelen lyhyesti direktiivin tuomia muutoksia Suomen lainsäädäntöön. Tutkielmani loppupäätelmä on, että vaikka vahingonkorvausdirektiivi ei täydellisesti paranna vahingonkärsijän asemaa, se selkeyttää monella tavalla kilpailuoikeudellisten vahingonkorvauskanteiden nykyistä tilaa, ja saattaa tietyssä määrin rohkaista vahingonkärsijiä hakemaan korvausta kärsimästään vahingosta.

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This study examined work engagement among brain injury rehabilitation professionals with specific attention to how they engage with their work (the extent to which they experience vigor, dedication, and absorption while working) and how they engage with people (the degree to which they are welcoming towards others and demonstrate integrity, responsibility, transparency). This study also tested a theoretical model of work engagement that predicted a relationship between engagement and personal, interpersonal, and organizational capacity. Eighty-one staff employed in a hospital-based brain injury program participated in the study. A quantitative self-report survey was used to measure participants' levels of capacity and engagement and a qualitative question was included to identify initiatives that could be introduced to enhance job performance. As predicted by the model, there were statistically significant positive correlations among all three capacity variables and engagement with work and statistically significant positive correlations between ethical engagement and personal and interpersonal capacity. The results of the qualitative data analysis revealed three broad categories of recommendations for improving job performance (more learning opportunities, more resources to support professional development, and the need to build greater team cohesion). These findings provide initial support for a theoretical model that emphasizes the link between capacity and engagement, which could be used to guide theory-driven interventions aimed at improving the work environment.