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Some Significant Results in the Classification Analysis of the Spectroscopic Evaluation of Cervical CancerShen, C 12 June 2006 (has links)
Cervical Cancer is the second most common type of cancer in women worldwide (500,000 cases/year) and one of the leading causes of cancer-related mortality in women in developing countries (230,000 cases/year). The Spectrx LightTouch™ device uses light to detect chemical and structural changes in cervical tissue. Light responds differently when exposed to normal cells and cancerous cells. The purpose of this research is to find the best model that can be used to diagnose the early cervical cancerous conditions. To achieve this goal, we first tried to reduce the number of variables. We use statistical and non-statistical methods to search for useful explanatory variables. Partial Least Square, Logistic Regression, CART, MARS, SVM have been used to build models. Bootstrap was adopted to estimate the threshold of PLS model. Comparison of the results indicates that PLS produces relatively better model in terms of the performances and to control over model threshold.
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Vad vill barnet? : En socialpsykologisk studie om hur montessoripedagoger bemöter barns viljaCouture, Anaëlle, Stefan, Fredriksson January 2015 (has links)
Syftet med vår undersökning är att skapa en utökad förståelse för hur montessoripedagogiken bidrar till barns psykosociala utveckling. För att undersöka vår huvudfråga, hur montessoripedagoger bemöter barns vilja, har vi genomfört en kvalitativ undersökning på montessoriförskolor i Halland. Vårt insamlade empiriska material, av intervjuer och observationer, visar att det som utmärker montessori som pedagogisk inriktning är att barnet är i centrum och att pedagogerna står tillbaka med sin egen auktoritet för att inte hindra barnets spontana aktivitet. Pedagogerna använder sig också av olika pedagogiska handlingar för att stimulera att barnen får frihet under ansvar. Utkomsten av de pedagogiska handlingarna har betydelse för barnens psykosociala utveckling då de bidrar till att utveckla självmedvetenhet, en förmåga att reagera och agera med hänsyn till både sig själv och andra. Vi har analyserat vårt material med våra socialpsykologiska teorier, George Mead, Moira Von Wright och Johan Asplund. Resultatet från analysen visar även att en viktig del är att pedagogerna växelverkar mellan sitt eget och barnets perspektiv, att det sker en dialog mellan pedagoger och barn och att barnen i en omgivning där de bemöts av äkta gensvar stimuleras till självmedvetenhet. Sålunda är vår slutsats att montessoripedagogernas bemötande stimulerar ett mer relationsorienterat perspektiv.
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Short-Sighted Probabilistic PlanningTrevizan, Felipe W. 01 August 2013 (has links)
Planning is an essential part of intelligent behavior and a ubiquitous task for both humans and rational agents. One framework for planning in the presence of uncertainty is probabilistic planning, in which actions are described by a probability distribution over their possible outcomes. Probabilistic planning has been applied to different real-world scenarios such as public health, sustainability and robotics; however, the usage of probabilistic planning in practice is limited due to the poor performance of existing planners.
In this thesis, we introduce a novel approach to effectively solve probabilistic planning problems by relaxing them into short-sighted problems. A short-sighted problem is a relaxed problem in which the state space of the original problem is pruned and artificial goals are added to heuristically estimate the cost of reaching an original goal from the pruned states. Differently from previously proposed relaxations, short-sighted problems maintain the original structure of actions and no restrictions are imposed in the maximum number of actions that can be executed. Therefore, the solutions for short-sighted problems take into consideration all the probabilistic outcomes of actions and their probabilities. In this thesis, we also study different criteria to generate short-sighted problems, i.e., how to prune the state space, and the relation between the obtained short-sighted models and previously proposed relaxation approaches.
We present different planning algorithms that use short-sighted problems in order to solve probabilistic planning problems. These algorithms iteratively generate and execute optimal policies for short-sighted problems until the goal of the original problem is reached. We also formally analyze the introduced algorithms, focusing on their optimality guarantees with respect to the original probabilistic problem. Finally, this thesis contributes a rich empirical comparison between our algorithms and state-of-the-art probabilistic planners.
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Behaviour of PVC Encased Reinforced Concrete Walls under Eccentric Axial LoadingAbdel Havez, Amr January 2014 (has links)
Stay-in-place (SIP) formwork has been used as an alternative to the conventional formwork system. The systems are mainly assembled on site, hence simplifying the construction process and reducing the construction time as the removal procedure has been eliminated. SIP formwork systems can be divided into two main categories; structural and non-structural formwork, based on their contribution to resist applied loads. The structural formwork provides the same advantages as the non-structural formwork, in addition to its contribution to resist the applied loads. As a result, the cross section and the reinforcement of the structural member can be reduced. Recently, polyvinyl chloride (PVC) has been used as a stay-in-place formwork because of its lower cost compared to other materials, durability, and ease to assemble.
The PVC SIP formwork consists of interconnected elements; panels and connectors that serve as permanent formwork for the concrete walls. In this study, the behaviour of the PVC encased reinforced concrete walls under eccentric compression loading was investigated. The variables in this study were the type of the specimen (PVC encased or control), the longitudinal reinforcement (4-10M or 4-15M rebars) and the eccentricity of the applied compression load (33.87 mm, 67.73 mm and 101.6 mm). Generally, the control walls (without PVC encasement) failed by yielding of the steel followed by crushing of the concrete, or by crushing of the concrete without yielding of the steel. For the PVC encased walls, buckling of the PVC occurred after the concrete crushed. The PVC encased specimens showed a higher peak load than their peer control walls. The effect of the PVC on increasing the ultimate capacity at a given eccentricity was more significant for the walls reinforced with 4-10M than the walls reinforced with 4-15M. For the lowest reinforcement ratio (4-10M), the PVC encased specimens showed an increase in peak load by 37.2% and 17.1% at an eccentricity of 67.73 mm and 101.6 mm, respectively. When the reinforcement was increased to 4-15 M, the increase in the peak load dropped at all eccentricities to 10%. For the vertical and the mid-span deflection, the PVC encased specimens and the control specimens showed the same values. Also, the test results showed an increase in the energy absorption capacity for the PVC encased specimens compared to the controls specimens, where the effect for the walls reinforced with 4-10M was higher than the walls reinforced with 4-15M at a given eccentricity.
An analytical model was developed to predict the ultimate load capacity of the specimens taking into consideration the effect of the PVC on the load carrying capacity of the walls. The provision was derived based on the moment magnification factor method in which the effect of secondary stresses associated with the column deformations was taken into consideration. The calculated capacities of the PVC encased specimens showed a conservative error of 5.9% on average.
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Orientation and Transitions of Lyotropic Lamellar Phase under ShearSu, Haipeng January 2014 (has links)
The intention of this study is to investigate the evolution and transition of lyotropic lamellar phase and the formation of multi-lamellar vesicles (MLVs) under shear flow, since the shear technology can be used to produce well defined multi-lamellar vesicles which are useful for encapsulating drugs in medical or research fields. The system was designed to stabilize and track one single multi-lamellar vesicle, which is being sheared under Couette shear flow between two co-rotational disks, by using polarizing microscope and a LabView program.
For the whole system, most parts of the hardware instrument and all the software programs were originally designed and homemade, which makes this a unique undertaking. Eighty percent of the time was spent on designing, assembling, testing and improving the hardware instrument and software programs to make sure the system can achieve our aim as accurately as possible.
The lyotropic lamellar phase sample is made of pentanol, dodecane, SDS and water. Nine different concentrations from 16% to 32% of SDS+Water were explored under five different shear rates from 3.3 to 13.2 . Sodium dodecyl sulfate (SDS) is a kind of surfactant which has an amphiphilic molecular structure, and a certain liquid crystal structure (such as a lamellar phase) will be formed when it is dissolved in a water/oil mixture solvent.
It is a great achievement that one single multi-lamellar vesicle is able to be followed for over 20 minutes under shear, and it is found that the multi-lamellar vesicle does not exhibit any obvious changes with time once it was already formed. Three different structural regions were found for the dilute lamellar phase while evolving to the multi-lamellar vesicle orientation state under shear. However, only two regions were found for the lamellar phase with higher concentrations under low shear rate since the lamellar phase will not reach to the multi-lamellar vesicle state. Besides, on the basis of the results of these experiments, it can be concluded that either higher shear rate or higher concentration of SDS+Water will hasten the formation of multi-lamellar vesicles. For the transition time of reaching a uniform multi-lamellar vesicle orientation state, it can be reduced by increasing shear rate. In addition, the results show that the transition time is decreasing more slowly for high concentrated lamellar phases than dilute lamellar phases with increasing the shear rate.
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Determinants of Regional Disparities in Under Age five Mortality in Cote d'IvoireAssi Kouame, Poquelin 16 May 2014 (has links)
ABSTRACT
Background: The launch of the Millennium Development Goal4, in 2000 and the national and international mobilization it spurs results to a decline of child under age five mortality rate from 90 per 1000 living birth in 1990 to 40 per thousands in 2012. That decline however is not evenly distributed across the globe and the majority of countries in the Sub-Saharan African region continue to experience a higher rate of under age five mortality than expected in 2013. Within country disparities in child mortality and it determinants was suggested to account for the lagging of those countries to reduce their under age five mortality rate. Objective: the study examined the variation in child mortality across statistical regions in Cote d’Ivoire and the community level factors that can explain those variations after controlling child, the mothers and the household characteristics. Method: The study used data obtained from the 2011-2012 Cote d’Ivoire’ Demography Health Survey. The study population consisted of 7511 children born within the 5 years preceding the survey. Frequency tables were created to show the distribution of the selected child mortality determinants across regions in Cote d’ivoire and three Logistic models were run to measure the association between the under age five mortality and the selected determinants. Results: The proportion of under age five mortality in the study population was 8.52%. There was a statistically significant variation in child mortality across regions. At the community level, the proportion of mothers with a least a secondary education was associated with under-age five mortality risk (OR=0.99, CI=0.98-0.99). There was no significant association between child mortality and the other selected community factors included in the study. Conclusion: This study reveals a significant variation of under age five mortality rate across region in Cote d’Ivoire, even after controlling or child, mother and household level factors. The findings of this study suggest a need for further exploration of the factors that can explain those differences.
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"The rhymer in the long tongued room" : Dylan Thomas and radioPietersma, Eric Geoffrey January 1995 (has links)
Dylan Thomas's relationship with radio is marked by an increasingly complex aesthetic response. The broadcasts which he wrote for the B.B.C. demonstrate a progressive refinement of technique and an increasingly original approach to the medium. Under Milk Wood, in many regards, represents the culmination of this broadcasting work; it is a remarkable response to the evocative potentials of radio. But the piece, apart from confirming Thomas's achievement in radio, also provides a unique vehicle for exploring critical treatment of a non-textual form like radio. The critical history of Under Milk Wood emphasises the need for a "form-sensitive" criticism appreciative of the artistic potentials and restrictions of radio. Finally, it is these potentials and restrictions, masterfully explored by Thomas, which can also be seen as exerting a powerful influence on Thomas's own artistic sensibility. The social essence of radio altered Thomas's own artistry.
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Corrosion Detection and Prediction StudiesNicola, Sally 2012 August 1900 (has links)
Corrosion is the most important mechanical integrity issues the petrochemical industry has to deal with. While significant research has been dedicated to studying corrosion, it is still the leading cause of pipeline failure in the oil and gas industry. Not only is it the main contributor to maintenance costs, but also it accounts for about 15-20% of releases from the petrochemical industry and 80% of pipeline leaks. Enormous costs are directed towards fixing corrosion in facilities across the globe every year. Corrosion has caused some of the worst incidents in the history of the industry and is still causing more incidents every year. This shows that the problem is still not clearly understood, and that the methods that are being used to control it are not sufficient.
A number of methods to detect corrosion exist; however, each one of them has shortcomings that make them inapplicable in some conditions, or generally, not accurate enough. This work focuses on studying a new method to detect corrosion under insulation. This method needs to overcome at least some of the shortcomings shown by the commercial methods currently used. The main method considered in this project is X-ray computed tomography. The results from this work show that X-ray computed tomography is a promising technique for corrosion under insulation detection. Not only does it detect corrosion with high resolution, but it also does not require the insulation to be removed. It also detects both internal and external corrosion simultaneously.
The second part of this research is focused on studying the behavior of erosion/corrosion through CFD. This would allow for determining the erosion/corrosion rate and when it would take place before it starts happening. Here, the operating conditions that led to erosion/corrosion (from the literature) are used on FLUENT to predict the flow hydrodynamic factors. The relationship between these factors and the rate of erosion/corrosion is studied. The results from this work show that along with the turbulence and wall shear stress, the dynamic pressure imposed by the flow on the walls also has a great effect on the erosion/corrosion rate.
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Dynamic Under Keel Clearance(DUKC) : Ökat godsflöde i svenska hamnar samt bibehållen sjötransportsäkerhetAxelsson, Jesper, Nordström, Kristian January 2008 (has links)
<p>Syftet med detta arbete var att undersöka om det fanns intresse för att införande av DUKC (Dynamic Under Keel Clearance) systemet i Sverige.Vi utgick ifrån en hamn i Australien, Port Hedland, som använt systemet sedan 1996, sedan tog vi reda på vad som användes i Sverige. För att få en bra grund sökte vi information om vad som krävdes för att DUKC skulle fungera tillfredställande. Vi Tog också del av en studie som man utfört i Mälaren som grundar sig på fartygs dynamiska rörelser och djupgående.Utifrån vår insamlade data ville vi fråga en sjöfartsrelaterad grupp och undersöka hur intresset för DUKC såg ut och skickade ut en enkät som även innehöll ett informationsblad.Efter sammanställning av erhållna svara framgick det att intresset för att införa just DUKC systemet inte var så stort men däremot ett system som gör det möjligt att säkerställa de krav som finns idag.</p>
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Choking under pressure - Evidence of the causal effect of audience size on performanceBöheim, René, Grübl, Dominik, Lackner, Mario 09 1900 (has links) (PDF)
We analyze performance under pressure and estimate the causal effect of audience size on the success of free throws in top-level professional basketball. We use data from the National Basketball Association (NBA) for the seasons 2007/08 through 2015/16. We exploit the exogenous variation in weather conditions on game day to establish a causal link between attendance size and performance. Our results confirm a sizeable and strong negative effect of the number of spectators on performance. Home teams in (non-critical) situations at the beginning of games perform worse when the audience is larger. This result is consistent with the theory of a home choke rather than a home field advantage. Our results have potentially large implications for general questions of workplace design and help to further understand how the social environment affects performance. We demonstrate that the amount of support, i.e. positive feedback, from a friendly audience does affect performance. / Series: Department of Economics Working Paper Series
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