903 resultados para problems on the real line


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Clinic simulation as a training and knowledge method allows people experiment a real event representation with the aim of acquiring knowledge, abilities and aptitudes. The filming of the staging represents a useful tool to review the decisions taken and the actions they did, with the purpose to highlight the strengths, weaknesses and the areas for improvement. The article describes a study carried out by a group of students in second course of nursing, and it tries to evaluate if there is any influence if somebody is filming you during the clinic simulation, does it make you do more errors or not?

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Tavoitteena on tutkia kuluttajille suunnatun markkinointiviestinnän lokalisointia Internetissä uuden tuotteen lanseerauksen yhteydessä. Vaikka Internet on globaali media, sen haasteena on tarjota paikallisesti kuluttajille merkityksellistä sisältöä, sekä ylläpitää yhtenäistä brandia. Tutkimus on toteutettu deskriptiivisenä tapaustutkimuksena globaalissa tietoliikenneyrityksessä, ja se perustuu haastatteluihin sekä valmiiseen aineistoon. Lyhentyneet kulutuselektroniikan elinkaaret, nopeat tuotelanseeraukset, kasvava yhteistyö ulkopuolisten kumppanien kanssa sekä markkinointiviestinnän integraation tarve aiheuttavat ajoitusongelmia lokalisointiin. Yhtenäinen web infrastruktuuri, työkalut ja globaalit prosessit mahdollistavat kustannustehokkaan lokalisoinnin business-tilanteen muuttuessa ja kultturieroista johtuen. Tässä tutkimuksessa on selvitetty neljän tekijän (ympäristö, tuote, kuluttaja, organisaatiostrategia) vaikutusta lokalisointiin. Jotta maiden parhaita menettelytapoja voidaan hyödyntää nykyistä paremmin ja välttää kultturierojen sivuuttaminen, tarvitaan sekä ’virallista’ että vapaamuotoista seurantaa. Globaalin Internet-sivuston ja lukuisten kansallisten sivustojen ylläpitäminen vaatii Internet-sivustojen fokuksen tarkkaa noudattamista, globaalia segmentointia, ja sen mukaista sisällön tarjontaa kuluttajille.

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Selektiivisten estrogeenireseptorin muuntelijoiden (serm) vaikutus rintasyöpäsolujen ja luun solujen kuolemaan Selektiiviset estrogeenireseptorin muuntelijat (SERMit) ovat ryhmä kemialliselta rakenteeltaan erilaisia yhdisteitä jotka sitoutuvat solunsisäisiin estrogeenireseptoreihin toimien joko estrogeenin kaltaisina yhdisteinä tai estrogeenin vastavaikuttajina. Tamoksifeeni on SERM –yhdiste, jota on jo pitkään käytetty estrogeenireseptoreita (ER) ilmentävän rintasyövän lääkehoidossa. Tamoksifeeni sekä estää rintasyöpäsolujen jakaantumista että toisaalta aikaansaa niiden apoptoosin eli ohjelmoidun solukuoleman muuntelemalla ER-välitteisesti kohdesolun geenien ilmentymistä. Viimeaikaiset tutkimustulokset ovat kuitenkin osoittaneet tamoksifeenilla olevan myös nopeampia, nongenomisia vaikutusmekanismeja. Tässä väitöskirjatyössä tutkimme niitä nopeita vaikutusmekanismeja joiden avulla tamoksifeeni vaikuttaa rintasyöpäsolujen elinkykyyn. Osoitamme että tamoksifeeni farmakologisina pitoisuuksina aikaansaa nopean mitokondriaalisen solukuolemaan johtavan signallointireitin aktivoitumisen rintasyöpäsoluissa. Tämän lisäksi tutkimme myös tamoksifeenin aiheuttamaan mitokondriovaurioon johtavia tekijöitä. Tutkimustuloksemme osoittavat että ER-positiivisissa rintasyöpäsoluissa tamoksifeeni indusoi pitkäkestoisen ERK-kinaasiaktivaation, joka voidaan estää 17-beta-estradiolilla. Tamoksifeenin aikaansaama nopea solukuolema on pääosin ER:sta riippumaton tapahtuma, mutta siihen voidaan vaikuttaa myös ER-välitteisin mekanismein. Sen sijaan epidermaalisen kasvutekijäreseptorin (EGFR) voitiin osoittaa osallistuvan tamoksifeenin nopeiden vaikutusten välittämiseen. Tämän lisäksi vertailimme myös estradiolin ja eri SERM-yhdisteiden kykyä suojata apoptoosilta käyttämällä osteoblastiperäisiä soluja. Pytyäksemme vertailemaan ER-isotyyppien roolia eri yhdisteiden suojavaikutuksissa, transfektoimme U2OS osteosarkoomasolulinjan ilmentämään pysyvästi joko ERalfaa tai ERbetaa. Tulostemme mukaan sekä estradioli että uusi SERM-yhdiste ospemifeeni suojaavat osteoblastin kaltaisia soluja etoposidi-indusoidulta apoptoosilta. Sekä ERalfa että ERbeta pystyivät välittämään suojavaikutusta, joskin vaikutukset erosivat toisistaan. Lisäksi havaitsimme edellä mainitun suojavaikutuksen olevan yhteydessä muutoksiin solujen sytokiiniekspressiossa. Tietoa SERM-yhdisteiden anti-ja proapoptoottisten vaikutusmekanismeista eri kohdekudoksissa voidaan mahdollisesti hyödyntää kehiteltäessä uusia kudosspesifisiä SERM-yhdisteitä.

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Industry's growing need for higher productivity is placing new demands on mechanisms connected with electrical motors, because these can easily lead to vibration problems due to fast dynamics. Furthermore, the nonlinear effects caused by a motor frequently reduce servo stability, which diminishes the controller's ability to predict and maintain speed. Hence, the flexibility of a mechanism and its control has become an important area of research. The basic approach in control system engineering is to assume that the mechanism connected to a motor is rigid, so that vibrations in the tool mechanism, reel, gripper or any apparatus connected to the motor are not taken into account. This might reduce the ability of the machine system to carry out its assignment and shorten the lifetime of the equipment. Nonetheless, it is usually more important to know how the mechanism, or in other words the load on the motor, behaves. A nonlinear load control method for a permanent magnet linear synchronous motor is developed and implemented in the thesis. The purpose of the controller is to track a flexible load to the desired velocity reference as fast as possible and without awkward oscillations. The control method is based on an adaptive backstepping algorithm with its stability ensured by the Lyapunov stability theorem. As a reference controller for the backstepping method, a hybrid neural controller is introduced in which the linear motor itself is controlled by a conventional PI velocity controller and the vibration of the associated flexible mechanism is suppressed from an outer control loop using a compensation signal from a multilayer perceptron network. To avoid the local minimum problem entailed in neural networks, the initial weights are searched for offline by means of a differential evolution algorithm. The states of a mechanical system for controllers are estimated using the Kalman filter. The theoretical results obtained from the control design are validated with the lumped mass model for a mechanism. Generalization of the mechanism allows the methods derived here to be widely implemented in machine automation. The control algorithms are first designed in a specially introduced nonlinear simulation model and then implemented in the physical linear motor using a DSP (Digital Signal Processor) application. The measurements prove that both controllers are capable of suppressing vibration, but that the backstepping method is superior to others due to its accuracy of response and stability properties.

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Some problems involved in the interpretation of Hall‐effect measurements in polycrystalline semiconductors have not been resolved, especially when the contribution of the boundaries is appreciable. Using the Herring theory of transport properties in inhomogeneous semiconductors, we present an alternative interpretation to that previously proposed. This model permits the calculation of the Hall coefficient under general conditions.

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UNLABELLED: Phenomenon: Assuring quality medical care for all persons requires that healthcare providers understand how sociocultural factors affect a patient's health beliefs/behaviors. Switzerland's changing demographics highlight the importance of provider cross-cultural preparedness for all patients-especially those at risk for social/health precarity. We evaluated healthcare provider cross-cultural preparedness for commonly encountered vulnerable patient profiles. APPROACH: A survey on cross-cultural care was mailed to Lausanne University hospital's "front-line healthcare providers": clinical nurses and resident physicians at our institution. Preparedness items asked "How prepared do you feel to care for ... ?" (referring to example patient profiles) on an ascending 5-point Likert scale. We examined proportions of "4 - well/5 - very well prepared" and the mean composite score for preparedness. We used linear regression to examine the adjusted effect of demographics, work context, cultural-competence training, and cross-cultural care problem awareness, on preparedness. FINDINGS: Of 885 questionnaires, 368 (41.2%) were returned: 124 (33.6%) physicians and 244 (66.4%) nurses. Mean preparedness composite was 3.30 (SD = 0.70), with the lowest proportion of healthcare providers feeling prepared for patients "whose religious beliefs affect treatment" (22%). After adjustment, working in a sensitized department (β = 0.21, p = .01), training on the history/culture of a specific group (β = 0.25, p = .03), and awareness regarding (a) a lack of practical experience caring for diverse populations (β = 0.25, p = .004) and (b) inadequate cross-cultural training (β = 0.18, p = .04) were associated with higher preparedness. Speaking French as a dominant language and physician role (vs. nurse) were negatively associated with preparedness (β = -0.26, p = .01; β = -0.22, p = .01). Insights: The state of cross-cultural care preparedness among Lausanne's front-line healthcare providers leaves room for improvement. Our study points toward institutional strategies to improve preparedness: notably, making sure departments are sensitized to cross-cultural care resources and increasing provider diversity to reflect the changing Swiss demographic.

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Despite the low biodegradability of seawater NOM, problems associated with biofouling are common in facilities that handle seawater. In this work, a fixed-film aerobic biofilter is proposed as an effective unit for preventing biofouling in such facilities. A packed-bed biofilter with an EBCT = 6 - 11 min was employed. The results demonstrated that the DOC is reduced by 6% and the BOD7 is reduced up to 15%. The LC-OCD analysis revealed that biofiltration abates the LMW neutrals and biopolymer fractions by 33 and 17%, respectively. However, the fractionation with UF membrane showed that the biofiltration process is able to degrade the more biodegradable compounds that have molecular weights that are greater than 1 kDa and compounds with molecular weights of less than 1 kDa. After biofiltration, the biological activity measured in terms of ATP removal was reduced by 60%. Finally, a test to evaluate the biofilm formation capacity of a water sample revealed reductions of ~94% when comparing biofiltered and non-biofiltered seawater. Therefore, a fixed-film aerobic biofiltration process could be a useful treatment for the removal of biodegradable organic matter from seawater and for improving the water quality in terms of less biofilm formation capacity.

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Laboratory and field experiments have demonstrated in many cases that malaria vectors do not feed randomly, but show important preferences either for infected or non-infected hosts. These preferences are likely in part shaped by the costs imposed by the parasites on both their vertebrate and dipteran hosts. However, the effect of changes in vector behaviour on actual parasite transmission remains a debated issue. We used the natural associations between a malaria-like parasite Polychromophilus murinus, the bat fly Nycteribia kolenatii and a vertebrate host the Daubenton's bat Myotis daubentonii to test the vector's feeding preference based on the host's infection status using two different approaches: 1) controlled behavioural assays in the laboratory where bat flies could choose between a pair of hosts; 2) natural bat fly abundance data from wild-caught bats, serving as an approximation of realised feeding preference of the bat flies. Hosts with the fewest infectious stages of the parasite were most attractive to the bat flies that did switch in the behavioural assay. In line with the hypothesis of costs imposed by parasites on their vectors, bat flies carrying parasites had higher mortality. However, in wild populations, bat flies were found feeding more based on the bat's body condition, rather than its infection level. Though the absolute frequency of host switches performed by the bat flies during the assays was low, in the context of potential parasite transmission they were extremely high. The decreased survival of infected bat flies suggests that the preference for less infected hosts is an adaptive trait. Nonetheless, other ecological processes ultimately determine the vector's biting rate and thus transmission. Inherent vector preferences therefore play only a marginal role in parasite transmission in the field. The ecological processes rather than preferences per se need to be identified for successful epidemiological predictions.

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Current-day web search engines (e.g., Google) do not crawl and index a significant portion of theWeb and, hence, web users relying on search engines only are unable to discover and access a large amount of information from the non-indexable part of the Web. Specifically, dynamic pages generated based on parameters provided by a user via web search forms (or search interfaces) are not indexed by search engines and cannot be found in searchers’ results. Such search interfaces provide web users with an online access to myriads of databases on the Web. In order to obtain some information from a web database of interest, a user issues his/her query by specifying query terms in a search form and receives the query results, a set of dynamic pages that embed required information from a database. At the same time, issuing a query via an arbitrary search interface is an extremely complex task for any kind of automatic agents including web crawlers, which, at least up to the present day, do not even attempt to pass through web forms on a large scale. In this thesis, our primary and key object of study is a huge portion of the Web (hereafter referred as the deep Web) hidden behind web search interfaces. We concentrate on three classes of problems around the deep Web: characterization of deep Web, finding and classifying deep web resources, and querying web databases. Characterizing deep Web: Though the term deep Web was coined in 2000, which is sufficiently long ago for any web-related concept/technology, we still do not know many important characteristics of the deep Web. Another matter of concern is that surveys of the deep Web existing so far are predominantly based on study of deep web sites in English. One can then expect that findings from these surveys may be biased, especially owing to a steady increase in non-English web content. In this way, surveying of national segments of the deep Web is of interest not only to national communities but to the whole web community as well. In this thesis, we propose two new methods for estimating the main parameters of deep Web. We use the suggested methods to estimate the scale of one specific national segment of the Web and report our findings. We also build and make publicly available a dataset describing more than 200 web databases from the national segment of the Web. Finding deep web resources: The deep Web has been growing at a very fast pace. It has been estimated that there are hundred thousands of deep web sites. Due to the huge volume of information in the deep Web, there has been a significant interest to approaches that allow users and computer applications to leverage this information. Most approaches assumed that search interfaces to web databases of interest are already discovered and known to query systems. However, such assumptions do not hold true mostly because of the large scale of the deep Web – indeed, for any given domain of interest there are too many web databases with relevant content. Thus, the ability to locate search interfaces to web databases becomes a key requirement for any application accessing the deep Web. In this thesis, we describe the architecture of the I-Crawler, a system for finding and classifying search interfaces. Specifically, the I-Crawler is intentionally designed to be used in deepWeb characterization studies and for constructing directories of deep web resources. Unlike almost all other approaches to the deep Web existing so far, the I-Crawler is able to recognize and analyze JavaScript-rich and non-HTML searchable forms. Querying web databases: Retrieving information by filling out web search forms is a typical task for a web user. This is all the more so as interfaces of conventional search engines are also web forms. At present, a user needs to manually provide input values to search interfaces and then extract required data from the pages with results. The manual filling out forms is not feasible and cumbersome in cases of complex queries but such kind of queries are essential for many web searches especially in the area of e-commerce. In this way, the automation of querying and retrieving data behind search interfaces is desirable and essential for such tasks as building domain-independent deep web crawlers and automated web agents, searching for domain-specific information (vertical search engines), and for extraction and integration of information from various deep web resources. We present a data model for representing search interfaces and discuss techniques for extracting field labels, client-side scripts and structured data from HTML pages. We also describe a representation of result pages and discuss how to extract and store results of form queries. Besides, we present a user-friendly and expressive form query language that allows one to retrieve information behind search interfaces and extract useful data from the result pages based on specified conditions. We implement a prototype system for querying web databases and describe its architecture and components design.

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The work aims to analyze the possibilities of utilizing old crane driving AC induction motors in modern pulse-width-modulated variable frequency drives. Bearing currents and voltage stresses are the two main problems associated with modern IGBT inverters, and they may cause premature failure of an old induction motor. The origins of these two problems are studied. An analysis of the mechanism of bearing failure is proposed. Certain types of bearing currents are considered in detail. The most effective and economical means are chosen for bearing currents mitigation. Transient phenomena of cables and mechanism of over voltages occurring at motor terminals are studied in the work. The weakest places of the stator winding insulation system are shown and recommendations are given considering the mitigation of voltage stresses. Only the most appropriate and cost effective preventative methods are chosen for old motor drives. Rewinding of old motors is also considered.

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Coastal birds are an integral part of coastal ecosystems, which nowadays are subject to severe environmental pressures. Effective measures for the management and conservation of seabirds and their habitats call for insight into their population processes and the factors affecting their distribution and abundance. Central to national and international management and conservation measures is the availability of accurate data and information on bird populations, as well as on environmental trends and on measures taken to solve environmental problems. In this thesis I address different aspects of the occurrence, abundance, population trends and breeding success of waterbirds breeding on the Finnish coast of the Baltic Sea, and discuss the implications of the results for seabird monitoring, management and conservation. In addition, I assess the position and prospects of coastal bird monitoring data, in the processing and dissemination of biodiversity data and information in accordance with the Convention on Biological Diversity (CBD) and other national and international commitments. I show that important factors for seabird habitat selection are island area and elevation, water depth, shore openness, and the composition of island cover habitats. Habitat preferences are species-specific, with certain similarities within species groups. The occurrence of the colonial Arctic Tern (Sterna paradisaea) is partly affected by different habitat characteristics than its abundance. Using long-term bird monitoring data, I show that eutrophication and winter severity have reduced the populations of several Finnish seabird species. A major demographic factor through which environmental changes influence bird populations is breeding success. Breeding success can function as a more rapid indicator of sublethal environmental impacts than population trends, particularly for long-lived and slowbreeding species, and should therefore be included in coastal bird monitoring schemes. Among my target species, local breeding success can be shown to affect the populations of the Mallard (Anas platyrhynchos), the Eider (Somateria mollissima) and the Goosander (Mergus merganser) after a time lag corresponding to their species-specific recruitment age. For some of the target species, the number of individuals in late summer can be used as an easier and more cost-effective indicator of breeding success than brood counts. My results highlight that the interpretation and application of habitat and population studies require solid background knowledge of the ecology of the target species. In addition, the special characteristics of coastal birds, their habitats, and coastal bird monitoring data have to be considered in the assessment of their distribution and population trends. According to the results, the relationships between the occurrence, abundance and population trends of coastal birds and environmental factors can be quantitatively assessed using multivariate modelling and model selection. Spatial data sets widely available in Finland can be utilised in the calculation of several variables that are relevant to the habitat selection of Finnish coastal species. Concerning some habitat characteristics field work is still required, due to a lack of remotely sensed data or the low resolution of readily available data in relation to the fine scale of the habitat patches in the archipelago. While long-term data sets exist for water quality and weather, the lack of data concerning for instance the food resources of birds hampers more detailed studies of environmental effects on bird populations. Intensive studies of coastal bird species in different archipelago areas should be encouraged. The provision and free delivery of high-quality coastal data concerning bird populations and their habitats would greatly increase the capability of ecological modelling, as well as the management and conservation of coastal environments and communities. International initiatives that promote open spatial data infrastructures and sharing are therefore highly regarded. To function effectively, international information networks, such as the biodiversity Clearing House Mechanism (CHM) under the CBD, need to be rooted at regional and local levels. Attention should also be paid to the processing of data for higher levels of the information hierarchy, so that data are synthesized and developed into high-quality knowledge applicable to management and conservation.

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New economic and enterprise needs have increased the interest and utility of the methods of the grouping process based on the theory of uncertainty. A fuzzy grouping (clustering) process is a key phase of knowledge acquisition and reduction complexity regarding different groups of objects. Here, we considered some elements of the theory of affinities and uncertain pretopology that form a significant support tool for a fuzzy clustering process. A Galois lattice is introduced in order to provide a clearer vision of the results. We made an homogeneous grouping process of the economic regions of Russian Federation and Ukraine. The obtained results gave us a large panorama of a regional economic situation of two countries as well as the key guidelines for the decision-making. The mathematical method is very sensible to any changes the regional economy can have. We gave an alternative method of the grouping process under uncertainty.

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One of the problems with books which are relatively general in nature is that many of the individual contributions tend to be so narrow and specialised that only the author has any knowledge of (or interest in) the issues under discussion. At first sight this appears to be the case with Detecting Detection. Fortunately, however, first impressions are deceiving. Although the essays in the volume deal with writers as diverse and disparate as the Catalano-Spanish writer Juan Marse, the Bulgarian-French philosopher Julia Kristeva and the once-vaunted giant of English literature,Graham Greene, among numerous others, there is much to be enjoyed and learnt, even if some of the works under discussion are unfamiliar to the crime fiction reader and/or scholar to whom the book initially appears to be directed.

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The provision of Internet access to large numbers has traditionally been under the control of operators, who have built closed access networks for connecting customers. As the access network (i.e. the last mile to the customer) is generally the most expensive part of the network because of the vast amount of cable required, many operators have been reluctant to build access networks in rural areas. There are problems also in urban areas, as incumbent operators may use various tactics to make it difficult for competitors to enter the market. Open access networking, where the goal is to connect multiple operators and other types of service providers to a shared network, changes the way in which networks are used. This change in network structure dismantles vertical integration in service provision and enables true competition as no service provider can prevent others fromcompeting in the open access network. This thesis describes the development from traditional closed access networks towards open access networking and analyses different types of open access solution. The thesis introduces a new open access network approach (The Lappeenranta Model) in greater detail. The Lappeenranta Model is compared to other types of open access networks. The thesis shows that end users and service providers see local open access and services as beneficial. In addition, the thesis discusses open access networking in a multidisciplinary fashion, focusing on the real-world challenges of open access networks.

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In this work, we use the rule of mixtures to develop an equivalent material model in which the total strain energy density is split into the isotropic part related to the matrix component and the anisotropic energy contribution related to the fiber effects. For the isotropic energy part, we select the amended non-Gaussian strain energy density model, while the energy fiber effects are added by considering the equivalent anisotropic volumetric fraction contribution, as well as the isotropized representation form of the eight-chain energy model that accounts for the material anisotropic effects. Furthermore, our proposed material model uses a phenomenological non-monotonous softening function that predicts stress softening effects and has an energy term, derived from the pseudo-elasticity theory, that accounts for residual strain deformations. The model’s theoretical predictions are compared with experimental data collected from human vaginal tissues, mice skin, poly(glycolide-co-caprolactone) (PGC25 3-0) and polypropylene suture materials and tracheal and brain human tissues. In all cases examined here, our equivalent material model closely follows stress-softening and residual strain effects exhibited by experimental data