781 resultados para design-based survey sampling
Resumo:
Moving objects database systems are the most challenging sub-category among Spatio-Temporal database systems. A database system that updates in real-time the location information of GPS-equipped moving vehicles has to meet even stricter requirements. Currently existing data storage models and indexing mechanisms work well only when the number of moving objects in the system is relatively small. This dissertation research aimed at the real-time tracking and history retrieval of massive numbers of vehicles moving on road networks. A total solution has been provided for the real-time update of the vehicles’ location and motion information, range queries on current and history data, and prediction of vehicles’ movement in the near future. To achieve these goals, a new approach called Segmented Time Associated to Partitioned Space (STAPS) was first proposed in this dissertation for building and manipulating the indexing structures for moving objects databases. Applying the STAPS approach, an indexing structure of associating a time interval tree to each road segment was developed for real-time database systems of vehicles moving on road networks. The indexing structure uses affordable storage to support real-time data updates and efficient query processing. The data update and query processing performance it provides is consistent without restrictions such as a time window or assuming linear moving trajectories. An application system design based on distributed system architecture with centralized organization was developed to maximally support the proposed data and indexing structures. The suggested system architecture is highly scalable and flexible. Finally, based on a real-world application model of vehicles moving in region-wide, main issues on the implementation of such a system were addressed.
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This study examined the perceptions of state governmental officials and administrators from the state university system, community college system, and independent institutions concerning the ability of various groups to influence state-level higher education policy formation. The study was conducted in Florida for the period 1989-94. Florida has a history of legislative involvement in higher education, an unique system of state universities and community colleges, and a limited number of private institutions of higher education. This study was grounded in the works of Mortimer and McConnell (1978), Millett (1987), Marshall, Mitchell, and Wirt (1989) and Finitfer, Baldwin, and Thelin (1991). The study represented the application of an embedded, single-case design. A survey was the primary collection instrument. Respondents were asked questions concerning: (a) personal involvement in higher education, (b) perceptions of the ability of various groups to influence higher education policy, (c) the names of particular individuals considered key players in higher education policy formation, (d) important state-level documents, (e) personal knowledge of key areas of policy formation, and (f) emerging higher education issues in Florida. Quantitative and qualitative methods were used to analyze the different sections of the survey. The findings indicated that a power and influence hierarchy exists among the various groups that attempt to influence higher education policy and that this hierarchy is recognized by state government officials and higher education administrators. While an analysis of variance of the various groups revealed a few differences between state government officials and higher education personnel, the high overall agreement was an important finding. Leading members of the legislature, especially the Chair of the Senate Higher Education Committee, and key staff members, especially from the Senate Ways & Means Committee, were considered the most influential. Representatives from higher education institutions and research organizations were considered among the least influential. Emerging issues identified by the respondents included: (a) the political nature of state-level policy formation, (b) the role of legislative staff, (c) the competition for state moneys, (d) legislative concern for state-wide budgetary efficiency, and (e) legislative attempts to define quality and supervise academic program development for higher education.
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INTRODUCTION: Severe maternal morbidity , also known as maternal near miss , has been used as an alternative to the study of maternal mortality , since being more frequent shares the same determinants and enables the implementati on of epidem iological surveillance of cases . Since then, hospital audits ha ve been carried out to determine the rates of maternal near miss, its mai n causes and associated factors . More recently, population surveys based on self - reported morbidity have als o been presented as vi able in identifying these cases . OBJECTIVE: The aim of this study was to determine the prevalence and associated factors of maternal near miss and complications during pregnancy and puerperal period in Natal/RN. METHODS: A cross - secti onal population - based study was conducted in Natal /RN , Brazil, which has as its target population women aged 15 to 49 years who were pregnant in the last five years. It was carried out a probabilistic sam pling design based on a multi - stage complex sample , in which 60 census tracts were selected from three strata (north , south - east and west). Afterwards, domiciles were visited in order to obtain a sample of the 908 eligible women in whom a questionnaire was applied. The descriptive analyzes and bivariate ass ociations were performed using the Chi - square test and the estimate of the prevalence ratio (PR ) with 95% confidence interval (CI) and considering the weights and design effects . The Poisson regression analysis , also with 5% significance and 95% CI, was us ed for analyzes of associated factors. RESULTS: 848 women were identified and interviewed after visits in 8.227 households corresponding to a response rate of 93 . 4 %. The prevalence of maternal near miss was 41 . 1 /1 000NV, being the Intensive Care Unity stay i ng (19 . 1 /1 000 LB ) and eclampsia (13 . 5/1000LB) the most important marker s . The prevalence of complications in the puerperal peri od was 21 . 2 %, and hemorrhage (10 . 7%) and urinary tract infection (10 . 7%) the most frequently reported clinical conditions and rema in ing in the hospital for over a week after delivery the mo st frequent intervention (5.4%) . Regarding associated factors , the bivariate analysis showed an association between the increased number of complications in women of black/brown race ( PR= 1 . 23; CI95 % : 1 . 04 - 1 . 46) and lower socioeconomic status ( PR= 1 . 33; CI95%: 1 . 12 - 1 . 58) in women who had pre natal care in public service ( PR= 1 . 42; CI95%: 1 . 16 to 1 . 72 ) and that were not advised during prenatal about where they should do the d elivery (PR= 1 . 24; CI95%: 1 . 05 - 1 . 46), made the del ivery in the public service (PR= 1 . 63; CI95%: 1 . 30 - 2 . 03), had to search for more than one hospital for delivery (PR=1 . 22; CI95%: 1 . 03 - 1 . 45) and had no companion during childbirth ( PR =1 . 19; CI95%: 1 . 01 - 1 . 41) or at all times of childbirth c are - before, during and after childbirth - ( PR= 1 . 25, CI95%: 1 . 05 - 1 . 48) . Moreover, the number of days postpartum hospitalization was higher in women who had more complications (P R= 1 . 59 ; CI95%: 1 . 36 - 1 . 86). In the final regression model for both birth place (P R= 1 . 21 ; CI 95% : 1 . 02 to 1 . 44 ) and socioeconomic status (PR = 1.54 ; CI95%: 1 . 25 - 1 . 90 ) the association remained. CONCLUSION : Conducting population surveys using the pragmatic definition of near miss is feasible and may add importa nt information about this ev ent . It was possible to find the expression of health inequalities related to maternal health in the analysis of both socioeconomic conditions and on the utilization of health services.
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Nucleic acids (DNA and RNA) play essential roles in the central dogma of biology for the storage and transfer of genetic information. The unique chemical and conformational structures of nucleic acids – the double helix composed of complementary Watson-Crick base pairs, provide the structural basis to carry out their biological functions. DNA double helix can dynamically accommodate Watson-Crick and Hoogsteen base-pairing, in which the purine base is flipped by ~180° degrees to adopt syn rather than anti conformation as in Watson-Crick base pairs. There is growing evidence that Hoogsteen base pairs play important roles in DNA replication, recognition, damage or mispair accommodation and repair. Here, we constructed a database for existing Hoogsteen base pairs in DNA duplexes by a structure-based survey from the Protein Data Bank, and structural analyses based on the resulted Hoogsteen structures revealed that Hoogsteen base pairs occur in a wide variety of biological contexts and can induce DNA kinking towards the major groove. As there were documented difficulties in modeling Hoogsteen or Watson-Crick by crystallography, we collaborated with the Richardsons’ lab and identified potential Hoogsteen base pairs that were mis-modeled as Watson-Crick base pairs which suggested that Hoogsteen can be more prevalent than it was thought to be. We developed solution NMR method combined with the site-specific isotope labeling to characterize the formation of, or conformational exchange with Hoogsteen base pairs in large DNA-protein complexes under solution conditions, in the absence of the crystal packing force. We showed that there are enhanced chemical exchange, potentially between Watson-Crick and Hoogsteen, at a sharp kink site in the complex formed by DNA and the Integration Host Factor protein. In stark contrast to B-form DNA, we found that Hoogsteen base pairs are strongly disfavored in A-form RNA duplex. Chemical modifications N1-methyl adenosine and N1-methyl guanosine that block Watson-Crick base-pairing, can be absorbed as Hoogsteen base pairs in DNA, but rather potently destabilized A-form RNA and caused helix melting. The intrinsic instability of Hoogsteen base pairs in A-form RNA endows the N1-methylation as a functioning post-transcriptional modification that was known to facilitate RNA folding, translation and potentially play roles in the epitranscriptome. On the other hand, the dynamic property of DNA that can accommodate Hoogsteen base pairs could be critical to maintaining the genome stability.
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The feasibility of monitoring fluid flow subsurface processes that result in density changes, using the iGrav superconducting gravimeter, is investigated. Practical targets include steam-assisted gravity drainage (SAGD) bitumen depletion and water pumping from aquifers, for which there is currently a void in low-impact, inexpensive monitoring techniques. This study demonstrates that the iGrav has the potential to be applied to multi-scale and diverse reservoirs. Gravity and gravity gradient signals are forward modeled for a real SAGD reservoir at two time steps, and for surface-fed and groundwater-fed aquifer pumping models, to estimate signal strength and directional dependency of water flow. Time-lapse gravimetry on small-scale reservoirs exhibits two obstacles, namely, a µgal sensitivity requirement and high noise levels in the vicinity of the reservoir. In this study, both limitations are overcome by proposing (i) a portable superconducting gravimeter, and (ii) a pair of instruments under various baseline geometries. This results in improved spatial resolution for locating depletion zones, as well as the cancellation of noise common in both instruments. Results indicate that a pair of iGrav superconducting gravimeters meet the sensitivity requirements and the spatial focusing desired to monitor SAGD bitumen migration at the reservoir scales. For SAGD reservoirs, the well pair separation, reservoir depth, and survey sampling determine the resolvability of individual well pair depletion patterns during the steam chamber rising phase, and general reservoir depletion patterns during the steam chamber spreading phase. Results show that monitoring water table elevation changes due to pumping and tracking whether groundwater or surface water is being extracted are feasible.
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In this study, design based research in a teacher design team is performed. Teachers who intend to use social media to extend their school class teaching, are confronted with a lack of clear guidelines that inform them how to utilize them effectively. In this study, we aim at formulating such guidelines and testing their usefulness. First, opportunities to facilitate self-regulated learning (SRL) in higher education through the use of social media are elaborated in a literature study. Second, these opportunities are translated into teacher education to search for stimulating and limiting factors within the design, resulting in guidelines for effective social media integration.
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A new approach for overcoming the language and culture barriers to participation in MOOCs is reported. It is hypothesised that the juxtaposition of English as the language of instruction, used for interacting with course materials, and one’s preferred language as the language of participation, used for interaction with peers and facilitators, is preferable to ‘English only’ for participation in a MOOC. The HANDSON MOOC included seven teams of facilitators, each catering for a different language community. Facilitators were responsible for promoting active participation and peer tutoring. Comparing language groups revealed a series of predictors of intention to learn, some of which became apparent in the first days of the MOOC already. The comparison also uncovered four critical factors that influence participation: facilitation, language of participation, group size, and a pre-existing sense of community. Especially crucial was reaching a sufficient number of active participants during the first week. We conclude that multilingual facilitation activates participation in MOOCs in various ways; and that synergy between the four aforementioned factors is critical for the formation of the learning network that supports a social dynamics of active participation. Our approach suggests future targets for the development of the multilingual and community potential of MOOCs.
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De beoordeling van vorderingen en inzet van (extra) diagnostiek ('indicatiestelling') in het onderwijs kunnen de kans op het ontstaan van problemen bij een kind vergroten. Tijdige herkenning en preventieve ondervanging van de problemen vragen veranderingen in de inhoudelijke, evaluatieve, didactisch-organisatorische en diagnostische systematieken in en rond scholen. Daarom wordt gewerkt aan de opbouw van een inhoudelijk integrerende, pedagogisch-didactische kernstructuur (PDKS). Deze helpt de dialoog en samenwerking tussen opvoedeling(en) of leerling(en), opvoeder(s), leerkracht(en) en andere professionals eenduidig in te richten en te optimaliseren. Didactisch-organisatorische steun wordt verleend door passende software in de vorm van 'Diagnostische, Instructie en Management Systemen' (DIMS). De beoogde veranderingen worden samen met leerkrachten en schoolleidingen ontwikkeld en proefondervindelijk gerealiseerd in enkele scholen voor primair onderwijs. De schoolontwikkeling biedt de contextuele condities ter realisatie van 'verantwoorde zelfregulatie' van elk kind of elke leerling. Dit wordt toegelicht in verschillende praktijkvoorbeelden. Ook worden volgende ontwikkelingen geschetst.
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Een review van onderwijsanalyses en (beleids)onderzoeken verricht in de periode 1916-2015 wijst uit dat de reguliere jaarklassensystematiek in het Nederlandse primair en voortgezet onderwijs aanleiding geeft tot prestatie- en motivatieproblemen bij risico-leerlingen. Dit zijn met name de leerlingen die qua ontwikkelingspotenties of leervorderingen (aanvankelijk) duidelijk naar beneden of naar boven afwijken van leeftijdsgenoten in een groep of klas. Ondervanging van deze problemen lijkt mogelijk via een preventieve systematiek van ‘Optimaliserend Onderwijs’ voor elk kind in de vóór- of vroegschoolse educatie en elke leerling in het primair of voortgezet onderwijs. Een eerste vraag betreft de inhoudelijke en vormgevingskenmerken van dit onderwijsontwerp: welke richtlijnen en specificaties daarvan kunnen het onderwijs, spelen en leren voor elke leerling, zo optimaal mogelijk inhoud en vorm geven en hoe ziet een model van dit Optimaliserend Onderwijs eruit? Een tweede vraag is gericht op de realisatie van dit onderwijsontwerp: hoe is deze onderwijssystematiek te ontwikkelen in de Nederlandse schoolpraktijk? Gebruik van de sneeuwbalmethode in met name Nederlandse onderzoeks- en designliteratuur leidt tot beantwoording van de eerste vraag in de vorm van een multiniveau theoretisch ontwerp van ‘Optimaliserend Onderwijs’. Kernpunten hierin zijn: landelijke (deel)curricula gekenmerkt door instructievarianten; integratie van dubbele diagnostiek (individueel-longitudinaal en vergelijkend-genormeerd); flexibele certificerings- en diplomeringsstructuur; een ondersteunende schoolorganisatie; gecontroleerde opbrengst-optimalisering per kind of leerling en op instellings- en schoolniveau; per vóór- of vroegschoolse instelling of school(bestuur) kunnen ook vrije ofwel eigen onderwijsinvullingen worden ingericht. Beantwoording van de tweede vraag gebeurt met behulp van (onderzoeks)literatuur over multiniveau onderwijsinnovatie in de schoolpraktijk. Aanbevolen wordt om, op basis van een gezamenlijk besluit van het ministerie van Onderwijs, Cultuur en Wetenschap, de Tweede Kamer, relevante onderwijsinstanties, schoolbesturen en ouderorganisaties, te komen tot inrichting van samenhangende ontwikkelingsprojecten en -onderzoeken. Via een projectenserie in instellingen voor vóór- of vroegschoolse educatie en scholen voor primair en voortgezet onderwijs kan gecontroleerd worden samengewerkt tussen leid(st)ers, leerkrachten en docenten, scholen, ontwikkelings- en andere onderwijsinstellingen, instellingen voor onderzoek en informatietechnologie, en onderwijspolitiek. Tussenresultaten van Optimaliserend Onderwijs worden steeds in andere instellingen en scholen beproefd en verder verspreid.
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Kinderen worden in basisscholen veelal in leeftijdsgroepen ingedeeld. Er zijn dan steeds leerlingen die ten opzichte van leeftijdsgenoten heel goed of juist slecht presteren. Dit leidt bij deze 'relatief afwijkende leerlingen' tot demotivatie, gerichtheid op andere activiteiten, en 'onderpresteren'. In de hier voorgestane pedagogiek en didactiek wordt elk kind, per ontwikkelings- of competentiegebied, doorlopend en adequaat gesteund. Dit is ook conform de vigerende onderwijswetgeving. De praktische consequentie is dat het onderwijsaanbod in elke groep of klas steeds dient te zijn afgestemd op de werkelijke (begin)kenmerken van de aanwezige leerlingen. Vervolgens dient elk kind in school steeds iets boven het eigen niveau te kunnen spelen en leren, deels volgens eigen voorkeuren en eigen regulatie. Dit vereist voorbereide onderwijsleersituaties en een doorlopend helder inzicht in relevante diagnostische ontwikkelings- en leerniveaus alsmede in de individuele leerprocessen en -effecten. Praktische realisatie van deze eisen vraagt ten eerste om vaststelling van de beginkenmerken van leerlingen. Ten tweede dient het feitelijke speel- en leeraanbod te zijn georganiseerd in aansluiting op deze individuele beginkenmerken, in een meer flexibele vormgeving dan gebruikelijk. Deze twee onderwijsaspecten worden hier concreet uitgewerkt en ingevuld in het kader van een handleiding voor ontwikkelings- of design-based onderzoek dat samen met leerkrachten en management wordt uitgevoerd.
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In deze presentatie wordt ingegaan op mogelijkheden het onderwijs voor en het leren van jonge kinderen en leerlingen in het PO, VO en MBO te optimaliseren.
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Compulsory education laws oblige primary and secondary schools to give each pupil positive encouragement in, for example, social, emotional, cognitive, creative, and ethical respects. This is a fairly smooth process for most pupils, but it is not as easy to achieve with others. A pattern of pupil, home or family, and school variables turns out to be responsible for a long-term process that may lead to a pupil’s dropping out of education. A systemic approach will do much to introduce more clarity into the diagnosis, potential reduction and possible prevention of some persistent educational problems that express themselves in related phenomena, for example low school motivation and achievement; forced underachievement of high ability pupils; concentration of bullying and violent behaviour in and around some types of classes and schools; and drop-out percentages that are relatively constant across time. Such problems have a negative effect on pupils, teachers, parents, schools, and society alike. In this address, I would therefore like to clarify some of the systemic causes and processes that we have identified between specific educational and pupil characteristics. Both theory and practice can assist in developing, implementing, and checking better learning methods and coaching procedures, particularly for pupils at risk. This development approach will take time and require co-ordination, but it will result in much better processes and outcomes than we are used to. First, I will diagnose some systemic aspects of education that do not seem to optimise the learning processes and school careers of some types of pupils in particular. Second, I will specify cognitive, social, motivational, and self-regulative aspects of learning tasks and relate corresponding learning processes to relevant instructional and wider educational contexts. I will elaborate these theoretical notions into an educational design with systemic instructional guidelines and multilevel procedures that may improve learning processes for different types of pupils. Internet-based Information and Communication Technology, or ICT, also plays a major role here. Third, I will report on concrete developments made in prototype research and trials. The development process concerns ICT-based differentiation of learning materials and procedures, and ICT-based strategies to improve pupil development and learning. Fourth, I will focus on the experience gained in primary and secondary educational practice with respect to implementation. We can learn much from such practical experience, in particular about the conditions for developing and implementing the necessary changes in and around schools. Finally, I will propose future research. As I hope to make clear, theory-based development and implementation research can join forces with systemic innovation and differentiated assessment in educational practice, to pave the way for optimal “learning for self-regulation” for pupils, teachers, parents, schools, and society at large.
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Current trends in the automotive industry have placed increased importance on engine downsizing for passenger vehicles. Engine downsizing often results in reduced power output and turbochargers have been relied upon to restore the power output and maintain drivability. As improved power output is required across a wide range of engine operating conditions, it is necessary for the turbocharger to operate effectively at both design and off-design conditions. One off-design condition of considerable importance for turbocharger turbines is low velocity ratio operation, which refers to the combination of high exhaust gas velocity and low turbine rotational speed. Conventional radial flow turbines are constrained to achieve peak efficiency at the relatively high velocity ratio of 0.7, due the requirement to maintain a zero inlet blade angle for structural reasons. Several methods exist to potentially shift turbine peak efficiency to lower velocity ratios. One method is to utilize a mixed flow turbine as an alternative to a radial flow turbine. In addition to radial and circumferential components, the flow entering a mixed flow turbine also has an axial component. This allows the flow to experience a non-zero inlet blade angle, potentially shifting peak efficiency to a lower velocity ratio when compared to an equivalent radial flow turbine.
This study examined the effects of varying the flow conditions at the inlet to a mixed flow turbine and evaluated the subsequent impact on performance. The primary parameters examined were average inlet flow angle, the spanwise distribution of flow angle across the inlet and inlet flow cone angle. The results have indicated that the inlet flow angle significantly influenced the degree of reaction across the rotor and the turbine efficiency. The rotor studied was a custom in-house design based on a state-of-the-art radial flow turbine design. A numerical approach was used as the basis for this investigation and the numerical model has been validated against experimental data obtained from the cold flow turbine test rig at Queen’s University Belfast. The results of the study have provided a useful insight into how the flow conditions at rotor inlet influence the performance of a mixed flow turbine.
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För att ge insikt hur design för ett nytt rockalbum ska ske och ge information kring vad som bör finnas med på ett nytt omslag har denna studie utförts. Studien framförde information om att albumsgrafik var relevant. Först sades det att en nedåtgående trend gick att anta, eftersom den digitala musikbranschen tog över från den fysiska. Men det visade sig därefter vara precis lika stor försäljning på de fysiska albumen som de digitala. För att besvara målen i studien utfördes en visuell innehållsanalys och informationssökning på internet. Studiens syfte var att visuellt granska rockalbum från tre olika ursprungsländer, som var Sverige, Storbritannien och USA. Genom analysen kategoriserades designelement, teman och framtogs landstypiska albumomslag. Studien berörde även vem som styr designen av ett omslag samt ifall det kunde ses någon tongivande designer bland de album som ingick i analysen. I slutsatsen framgick det att Storbritannien och USA hade mycket lika grafiskt manér och att omslag från Sverige såg annorlunda ut. Det framgick även att banden styr utseendet på omslaget mer än designern, och från analysen framgick inte någon tongivande designer.
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Computer game technology produces compelling ‘immersive environments’ where our digitally-native youth play and explore. Players absorb visual, auditory and other signs and process these in real time, making rapid choices on how to move through the game-space to experience ‘meaningful play’. How can immersive environments be designed to elicit perception and understanding of signs? In this paper we explore game design and gameplay from a semiotic perspective, focusing on the creation of meaning for players as they play the game. We propose a theory of game design based on semiotics.