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Metacognition and Its Effect on Learning High School CalculusBergstresser, Bonnie Sue 08 July 2013 (has links)
The following paper discusses the effect of metacognitive training sessions on students calculus retention. Students in two high school classes participated. The students in both classes were then given lessons on a chapter without metacognitive training and lessons on a subsequent chapter with training in a set of metacognitive skills. After the latter chapter students scored higher on a post-test and expressed desire to incorporate the skills they learned into their other classes.
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Fraction Proficiency and the Number LineBass, Jeanne Elizabeth 08 July 2013 (has links)
The Common Core State Standards place special emphasis on developing fraction proficiency and the use of the number line, especially in grades three through five, whereas the previously mandated Louisiana Comprehensive Curriculum put lower priority on fractions and gave little attention to the number line as a model for fractions. The present study was performed in several 6th-grade math classrooms in rural Louisiana. We piloted fraction proficiency tests that were intended to check basic vocabulary and student access to various fraction models, as expected in the Common Core. Some strong error patterns were observed. They might be related to difference between the curricula. Recent work independent of this thesis discovered remarkably similar error patterns in California 6th-graders. The net outcome of this work is a step toward the design of better tests of fraction proficiency
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The Effects of the Peer Instruction Technique Think-Pair-Share on Students' Performance in ChemistryTrent, Kathleen Sipos 08 July 2013 (has links)
Think-Pair-Share is an active learning strategy which involves pairs of students discussing answers to questions or problems. The purpose of this study was to determine if the peer instruction technique Think-Pair-Share improved students performance in high-school chemistry. The teacher used one class of students as a control group. This group did not use Think-Pair-Share for the chapter investigated, Chemical Reactions. The teacher used two other classes of students, who did use Think-Pair-Share for this chapter, as the experimental group. There was no difference in the learning gains between the control and experimental groups. Think-Pair-Share and normal classroom instruction methods were equally effective. Factors such as small class size, absenteeism, quality of pre- and post-test questions, and the reluctance of the control group to stop using Think-Pair-Share may have contributed to these results. These issues are addressed, and a new, improved study design is suggested.
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Incorporating Calculus Concepts into a Middle School Mathematics ClassroomBailey, Randie Barbera 11 July 2013 (has links)
The Common Core State Standards for Mathematics were released in June of 2010 and full implementation into our schools is being required in the fall of 2013. The standards require teachers and students to be more focused and rigorous in what they teach and learn. This shift in learning towards focus, coherence, fluency, deep understanding, and applications was to improve math education in the United States so that our students become more competitive in the global economy of the 21st century and to help more students to be college and career ready by grade twelve. It is now necessary for teachers and students to be more prepared for both the Standards for Mathematical Content and the Standards for Mathematical Practice. With teachers giving students more opportunities to experience the usefulness of the mathematical language as outlined in the Standards for Mathematical Practice, students will be entering post-secondary education with a stronger mathematical background. Introducing students to more rigorous, more challenging, and more interesting mathematics in earlier grades will allow students to be more prepared to take on the challenges of a college-preparatory fourth math class in high school, whether it be honors, dual enrollment or advanced placement. This thesis shows how integrating basic calculus concepts into a middle school classroom through linear functions will allow students to be more aware of what a higher math class involves without having to be afraid of the unknown. Implementation of the Common Core Standards is requiring a big chunk of Advanced Mathematics, Geometry, and Algebra II to be moved down into lower grades, and eighth grade math is no exception. The thesis shows that eighth grade students are able to understand and apply elementary calculus concepts as long as they are taught with grade-appropriate language using what they already know. In fact, students in middle school, especially in eighth grade, do have the mental capability and mathematical maturity to do higher level mathematics and comprehend more advanced mathematical concepts and ideas if presented in the language of linear functions and basic triangle geometry.
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Controlling the Pore Size and Morphology of Mesoporous SilicaJohansson, Emma M. January 2010 (has links)
Mesoporous silica with a hexagonally ordered pore structure (SBA-15) has been synthesized. Through variations in the synthesis conditions several morphologies, such as fibers, sheets and separate rods, have been realized. Furthermore, additions of heptane and NH4F make it possible to synthesize SBA-15 with pores as large as 18 nm in the sheet morphology. Mechanisms for the formation of different morphologies have been suggested. In the case of fibers and sheets, the amount of heptane present during the synthesis determines the final morphology. For low concentrations, the heptane enters the micelles and increases the pore size while the particles (crystallites) attaches to each other end to end. When the heptane concentration increases, the heptane droplets increase in size, and above a critical droplet size the crystallites attach with one short end towards the droplet, forming the sheet morphology. The crystallites can also be separated. This is the case of the rod morphology. The separation is performed by shortening the stirring time and increasing the HCl concentration. The increased amount of HCl increases the hydration rate of the silica precursor, which can be used to control the thickness and length of the rods. Furthermore, the reaction time has been decreased from 20 h for all morphologies to less than 4 hours. The materials have been characterized with nitrogen sorption, electron microscopy and x-ray diffraction. Also, thermogravimetric analysis and fourier transformed infrared spectroscopy have been used for studying the removal of surfactants.
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Gene networks from high-throughput data : Reverse engineering and analysisGustafsson, Mika January 2010 (has links)
Experimental innovations starting in the 1990’s leading to the advent of high-throughput experiments in cellular biology have made it possible to measure thousands of genes simultaneously at a modest cost. This enables the discovery of new unexpected relationships between genes in addition to the possibility of falsify existing. To benefit as much as possible from these experiments the new inter disciplinary research field of systems biology have materialized. Systems biology goes beyond the conventional reductionist approach and aims at learning the whole system under the assumption that the system is greater than the sum of its parts. One emerging enterprise in systems biology is to use the high-throughput data to reverse engineer the web of gene regulatory interactions governing the cellular dynamics. This relatively new endeavor goes further than clustering genes with similar expression patterns and requires the separation of cause of gene expression from the effect. Despite the rapid data increase we then face the problem of having too few experiments to determine which regulations are active as the number of putative interactions has increased dramatic as the number of units in the system has increased. One possibility to overcome this problem is to impose more biologically motivated constraints. However, what is a biological fact or not is often not obvious and may be condition dependent. Moreover, investigations have suggested several statistical facts about gene regulatory networks, which motivate the development of new reverse engineering algorithms, relying on different model assumptions. As a result numerous new reverse engineering algorithms for gene regulatory networks has been proposed. As a consequent, there has grown an interest in the community to assess the performance of different attempts in fair trials on “real” biological problems. This resulted in the annually held DREAM conference which contains computational challenges that can be solved by the prosing researchers directly, and are evaluated by the chairs of the conference after the submission deadline. This thesis contains the evolution of regularization schemes to reverse engineer gene networks from high-throughput data within the framework of ordinary differential equations. Furthermore, to understand gene networks a substantial part of it also concerns statistical analysis of gene networks. First, we reverse engineer a genome-wide regulatory network based solely on microarray data utilizing an extremely simple strategy assuming sparseness (LASSO). To validate and analyze this network we also develop some statistical tools. Then we present a refinement of the initial strategy which is the algorithm for which we achieved best performer at the DREAM2 conference. This strategy is further refined into a reverse engineering scheme which also can include external high-throughput data, which we confirm to be of relevance as we achieved best performer in the DREAM3 conference as well. Finally, the tools we developed to analyze stability and flexibility in linearized ordinary differential equations representing gene regulatory networks is further discussed.
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Interface Engineering in Organic ElectronicsLindell, Linda January 2011 (has links)
Organic electronics is a field covering all applications and devices where one or several of the active components are made of organic material, such as organic light emitting diodes, organic solar cells, organic thin film transistors, organic magnets for spintronics etc. In all of the applications mentioned above, transport of charges across both inorganic/organic and organic/organic interfaces play a key role for device performance. In order to achieve high efficiencies and longer life-times, proper matching of the electronic energy levels of the different materials is needed. The aim of the research presented in this thesis has been to explore different routes to optimize interface energetics and gain deeper knowledge of the mechanisms that govern charge transport over the interface. Photoelectron spectroscopy (PES) is a method well suited to study both interactions between different materials taking place at surfaces as well as interface energetics. One way to achieve proper matching of interfaces energy levels is by adding a dipole layer. In the three first papers presented in the thesis, the method of adding a monolayer of small organic molecules to change the work function of the surface is investigated. We start with a model system consisting of a nickel surface and PPDA molecules where we have strong interaction and mixing of orbitals between the molecule and the metal surface. The second system consists of a gold surface and TDAE molecules with weaker interaction with integer electron transfer and finally in the third paper an organic surface VPP-PEDOT-Tos is modified, with TDAE, to create a transparent low work function organic electrode. In the fourth paper, we focus on gaining deeper understanding of the Integer Charge Transfer (ICT) model and the mechanisms governing the alignment of energy levels at organic/(in)organic interfaces and in the fifth paper we continue to challenge this model by using it to predict the behavior of a bilayer device, in terms of energy level alignment.
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Översyn av produktionslayout / Analys of layout for productionSpelmans, Daniel January 2009 (has links)
Det här examensarbetet har utförts på Metso Paper Karlstad AB, Karlstad. Arbetet ingår som avslutande del i maskiningenjörsprogrammet vid Karlstads universitet. Metso Paper Karlstad AB tillverkar mjukpappersmaskiner vilket man har gjort i drygt hundra år. Idag är man en världsledande leverantör med kunder över hela världen, hälften av världens mjukpapper (tissue) tillverkas idag på en maskin levererad från Metso. Produktionen vid Metso Paper Karlstad AB har under åren genomgått ett antal omorganisationer, vilka har påverkat tillverkningen. Någon större anpassning av verkstadslayouten har inte gjorts under de gångna åren vilket i sin tur har påverkat produktiviteten. Den sammanlagda verkstadsytan med tillhörande maskinpark är idag större än den för tissue aktuella produktionen är. Det finns därför ett behov av att finna nya externa kunder via utökad legotillverkning. Uppgiften för examensarbetet var att ta fram ett förslag för en flödesorienterad produktion, med hänsyn till nuvarande volym av produktion, för en anpassning mot eventuell tillverkning av delar till vindkraft. Resultatet visar att en ny layout för att få ett bättre flöde i dagens produktion inte kan motiveras mot vilka kostnader detta skulle medföra. Då operationstiderna är långa för produkterna i varje maskin, så är den tid och sträcka produkterna färdas mellan operationerna liten i sammanhanget. Förslaget för tillverkning av den nya produkten som studerats i rapporten är en layout som är snabb och billig att sätta upp, och tillåter en till att börja med mindre serietillverkning. Med ytterligare lite investeringar så kan en bra produktivitet uppnås utan att nuvarande produktion blir lidande. Ett koncept för tillverkning av den nya produkten på längre sikt togs fram, detta ska ses som ett förslag till underlag för vidareutveckling av produktionen. / This thesis has been carried out at Metso Paper Karlstad AB, Karlstad. The work is concluding part of a mechanical engineer program at Karlstad University. Metso Paper Karlstad AB manufactures tissue paper machines which they have done over a hundred years. Today they are a world leading supplier with customers all over the world, half of the world's tissue paper is currently produced on a machine supplied by Metso. The production at Metso Paper Karlstad AB has over the years undergone a number of reorganizations, which has affected the production. No major adjustment of the engineering layout has been made over the past few years which in turn has affected productivity. The total surface engineering and related machinery is now larger than that of tissue current production. There is therefore needed to find new external customers through expanded subcontracting. The task of the thesis was to develop a proposal for a flow-oriented production, with regard to the current volume of production, for an adaptation against possible manufacture of parts for wind power. The result shows that a new layout to get a better flow in the current production can not be justified against the costs that would entail. When the operation times are long for the products in each machine, so is the time and distance the products travel between operations small in the context. The proposal for the manufacture of the new product examined in this report is a layout that is quick and inexpensive to set up, and allows to start with smaller series. With a little additional investment a good productivity can be achieved without the current production is suffering. A concept for the production of the new product in the longer term was developed, this should be seen as a proposal for further development of production.
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Utveckling av korrugeringspress för kopparstrippningsmaskiner / Developing of corrugatingpress for copperstrippingmachinesFlödén, Stefan January 2009 (has links)
Uppdragsgivaren Outotec Kil AB marknadsför, konstruerar och levererar strippmaskiner för koppar och nickel. En del av denna strippmaskin för koppar är en korrugeringspress som pressar tre stycken veck över plåten. Var tredje plåt pressas och sedan staplas ett antal plåtar ihop till en bunt som senare smälts ner. Anledning till att var tredje plåt korrugeras är för att ge ett mellanrum mellan plåtarna som ger en snabbare och effektivare nedsmältning. Nuvarande korrugeringspress pressar tre stycken veck över hela plåtytan med ett djup på 30mm, vilket kräver en stor presskraft. Den stora presskraften kräver en kraftig konstruktion och det har gett vissa problem: Dyr att tillverka på grund av dyra och tunga komponenter. Stora hydraulcylindrar som kräver ett högt flöde. Tidigare hydraulcylindrar har monterats underifrån vilket gjort montering och service komplicerat. Fast inspänning av hydraulcylindrarna medför att dessa slits ut på kort tid. Målet med arbetet var att ta fram ett konstruktionsförslag för en korrugeringspress med ett nytt effektivare pressverktyg. Stativ och hydraulsystem skall vara dimensionerat för det nya pressverktyget. Konstruktionsförslaget skall innehålla ritningar på pressverktyg, stativ och kopplingsschema på hydraulsystem. Arbetet resulterade i ett pressverktyg som pressar fyra fördjupningar (härefter kallade vårtor) i plåtarna. Innerdiameter på vårtor blir 35mm och pressdjupet kommer att fortsätta vara 30mm. Presskraften som krävs för fyra vårtor blir totalt 1500kN. Fyra hydraulcylindrar med en kolvdiameter på 200mm kommer att användas och dessa kommer att drivas av två stycken hydraulpumpar. Hydraulcylindrarna är något överdimensionerade för att slita mindre på hydraulsystemet, dessutom finns marginal för att kunna höja oljetrycket om en högre presskraft skulle behövas. Stativet kommer att bestå av grovplåtar och kommer att vara kraftigt för att undvika utmattning. Hydraulcylindrarna kommer att sitta fast i plattor i överkant för att enkelt kunna lyftas ut rakt upp. / The commissioner for this assignment is Outotec Kil AB which are marketing, designing and delivering strippingmachines for copper and nickel. One part of this strippingmachine for copper is a corrugatingpress which presses three folds over the plate. Every third sheet is pressed and then a number of plates get stacked together, later to be melted. The reason why every third plate gets corrugated is to provide a space between the plates that allows a faster and more efficient meltingprocess. Current corrugatingspress make three folds over the entire plate surface, which requires a high pressure force. This force requires a strong design and it has some problems: Expensive to manufacture because of the expensive and heavy components. Large hydraulic cylinders that require a high oilflow. Earlier hydraulic cylinders were mounted from beneath which made the installation and service complicated. Because of a rigid attachment of the hydraulic cylinders these are subjected to excessive wear. The aim of this work was to develop a design proposal for a corrugatingspress with a new more efficient presstool. Stand and hydraulic system must be dimensioned for the new press tool. The design shall include drawings of the press, stand and a diagram of the hydraulic system. The work resulted in a presstool which presses four deepenings in the plate. Inner diameter of the deepenings are 35mm and depth will be 30mm. The pressforce needed for the four deepenings are totally 1500kN. Four hydraulic cylinders with a piston diameter of 200mm will be used and these will be driven by two hydraulic pumps. Hydraulic cylinders are slightly oversized to wear less on the hydraulic system. There´re also a margin to increase the oilpressure if a higher pressforce would be needed. The stand will be composed of thick steelplates and will be slightly oversized to avoid fatigue. The hydraulic cylinders will be bolted in steelplates in the top, then the steelplates will be bolted into the stand for an easy removal straight up.
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Development of an Identification System for Modules used in Medical EnvironmentsLindh, Joakim January 2011 (has links)
The objective of this thesis work is to find a suitable automatic identification solution for a medical system that utilizes several types of attachments. The solution should be cost efficient and sustainable enough to endure the medical environment. The thesis work was performed for Sectra Mamea AB in Linköping, Sweden. Five suitable solutions where evaluated on a theoretical basis and the feasibility of three of them were also experimentally verified on a more practical level. The experiments where performed on a Xilinx Virtex-5 FPGA platform with solution specific prototype boards, which were custom designed during the thesis work. The software development was made in several environments, where programming languages C, C# and VHDL were used. It was found that a solution based on 1-Wire technology was the most cost efficient and best-suited among the candidates. This was proven by validation of the technology and a thorough comparison to the other feasible solutions. This thesis presents the theory and practical results of the research. It is meant to serve as a comprehensive foundation supporting the decisions of future development.
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