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Modelling of the DNA Helix’s Duration for Genome SequencingDzubur, Sabina, Sharif, Rim January 2021 (has links)
Nanopore sequencing is the next generation ofsequencing methods which promises to deliver cheaper andmore portable genome sequencing capabilities. A single DNAor RNA strand is passed through a nanopore nested in anartificial membrane with an electric potential applied across it.The nucleotide bases of the helix then interact with the ioniccurrent in the nanopore, resulting in a unique signal that canbe translated into the correct corresponding nucleotide sequence.This project investigated whether features of the raw signal datacould be used as predictive indicators of the duration time ofeach nucleotide base in the nanopore. This is done in orderto segment the signal before translation. The training data setused came from the sequenced DNA molecules of an E. Colibacterium. Distribution candidates were fitted to a histogram ofthe duration data of the training set. Features of the currentsignal and distribution parameters were correlated in orderinvestigate if a linear predictive model could be created. Theresults indicate that the feature zero-crossings is not an optimaloption for construction of a linear model, while the large jumpsand moving variance features often generate linear patterns. The parameter of the Log-logistic distribution had the best fit withthe lowest relative root mean square deviation (rRMSD) of 2.7%. / Nanopore sequencing är nästa generationensmetod för DNA sekvensering som kommer att bidra medbilligare och mer portabla sekvenseringsmöjligheter. Metodeninnebär att en enkelsträngad DNA eller RNA molekyl passerargenom porer i nanostorlek, placerade i ett artificiellt membransamtidigt som en elektrisk potential appliceras över membranet.Nukleotiderna i genmolekylen interagerar med jonströmmen iporen, vilket resulterar i en unik signal som kan översättas tillden korresponderande sekvensen av nukleotider som passerat.Detta projekt gick ut på att undersöka om egenskaper frånsignalen kan användas som predikativa indikatorer för varaktighetensom varje nukleotid befinner sig i membranporen. Dettaför att sedan kunna segmentera signalen före översättningen tillDNA sekvensen. Träningsdata som användes är sekvenserad DNAfrån en E. Coli bakterie. Kandiderande sannolikhetsfördelningaranpassades till ett histogram som beskriver varaktigheten.Egenskaperna och parametrar från fördelningarna korreleradesför att skapa en linjär modell. Resultatet visade att antaletskärningar i x-axeln som signalegenskap inte är det optimalavalet för konstruktion av en linjär modell. Skillnaden mellan två signalvärden som är mindre än en varierbar konstant ochglidande variansen som signalegenskaper genererar ofta linjäramönster. Resultatet visade även att sannolikhetsfördelningen Loglogistichade lägst relativ medelkvadratavvikelse (rRMSD) på 2.7%. / Kandidatexjobb i elektroteknik 2021, KTH, Stockholm
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Variable Selection in High-Dimensional DataReichhuber, Sarah, Hallberg, Johan January 2021 (has links)
Estimating the variables of importance in inferentialmodelling is of significant interest in many fields of science,engineering, biology, medicine, finance and marketing. However,variable selection in high-dimensional data, where the number ofvariables is relatively large compared to the observed data points,is a major challenge and requires more research in order toenhance reliability and accuracy. In this bachelor thesis project,several known methods of variable selection, namely orthogonalmatching pursuit (OMP), ridge regression, lasso, adaptive lasso,elastic net, adaptive elastic net and multivariate adaptive regressionsplines (MARS) were implemented on a high-dimensional dataset.The aim of this bachelor thesis project was to analyze andcompare these variable selection methods. Furthermore theirperformance on the same data set but extended, with the numberof variables and observations being of similar size, were analyzedand compared as well. This was done by generating models forthe different variable selection methods using built-in packagesin R and coding in MATLAB. The models were then used topredict the observations, and these estimations were compared tothe real observations. The performances of the different variableselection methods were analyzed utilizing different evaluationmethods. It could be concluded that some of the variable selectionmethods provided more accurate models for the implementedhigh-dimensional data set than others. Elastic net, for example,was one of the methods that performed better. Additionally, thecombination of final models could provide further insight in whatvariables that are crucial for the observations in the given dataset, where, for example, variable 112 and 23 appeared to be ofimportance. / Att skatta vilka variabler som är viktigai inferentiell modellering är av stort intresse inom mångaforskningsområden, industrier, biologi, medicin, ekonomi ochmarknadsföring. Variabel-selektion i högdimensionella data, därantalet variabler är relativt stort jämfört med antalet observeradedatapunkter, är emellertid en stor utmaning och krävermer forskning för att öka trovärdigheten och noggrannheteni resultaten. I detta projekt implementerades ett flertal kändavariabel-selektions-metoder, nämligen orthogonal matching pursuit(OMP), ridge regression, lasso, elastic net, adaptive lasso,adaptive elastic net och multivariate adaptive regression splines(MARS), på ett högdimensionellt data-set. Syftet med dettakandidat-examensarbete var att analysera och jämföra resultatenav dessa metoder. Vidare analyserades och jämfördes metodernasresultat på samma data-set, fast utökat, med antalet variableroch observationer ungefär lika stora. Detta gjordes genom attgenerera modeller för de olika variabel-selektions-metodernavia inbygga paket i R och programmering i MATLAB. Dessamodeller användes sedan för att prediktera observationer, ochestimeringarna jämfördes därefter med de verkliga observationerna.Resultaten av de olika variabel-selektions-metodernaanalyserades sedan med hjälp av ett flertal evaluerings-metoder.Det kunde fastställas att vissa av de implementerade variabelselektions-metoderna gav mer relevanta modeller för datanän andra. Exempelvis var elastic net en av metoderna sompresterade bättre. Dessutom drogs slutsatsen att kombineringav resultaten av de slutgiltiga modellerna kunde ge en djupareinsikt i vilka variabler som är viktiga för observationerna, där,till exempel, variabel 112 och 23 tycktes ha betydelse. / Kandidatexjobb i elektroteknik 2021, KTH, Stockholm
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A Convex Optimisation Approach to Portfolio Allocation / En Konvex Optimerings-metod för PortföljallokeringJyrkäs, Tim January 2023 (has links)
The mean variance framework (MV) developed by Markowitz in his groundbreaking paper offers a quantitative and rational approach to portfolio selection. It is well known to market practitioners however that the MV optimal portfolios tend to perform subpar. One of the issues of the MV portfolios is that they require the inverse of a large covariance matrix, which is often ill-conditioned. In this thesis, we develop a new approach to circumvent these issues. We propose an optimisation approach akin to least squares linear regression and compare the performance with an establish method, covariance shrinkage. When tested on a set of 30 futures contracts, we find that the models yield promising results albeit somewhat lower than that of the benchmark. / Mean variance ramverket (MV) framtaget av Markowitz i sin banbrytande artikel möjliggör en kvantitativ och rationell metod för portföljallokering. Det är däremot ett väletablerat faktum bland marknadsaktörer att Markowitz-optimala portföljer tenderar att prestera relativt dåligt. Ett av tillkortakommandena av ramverket är den ofta problemtyngda inverteringen av, den ofta stora, kovariansmatrisen som är illa konditionerad. I denna uppsats föreslår vi en ny metod för att kringgå detta problem. Vi föreslår en optimeringsmetodologi mycket lik minsta kvadratmetoden i linjär regression. Denna metod utvärderas sedan mot en vedertagen metod, kovarianskrympning. När vi utvärderar vår modell på 30 stycken terminskontrakt ser vi lovande resultat men finner en Sharpekvot något lägre än referensportföljens.
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Ocean Wave Simulation and PredictionYu, Sihan 10 September 2018 (has links)
WiFi can provide network coverage for users on land at anytime and anywhere, but on the sea, the wireless communication scenes change dramatically due to the signals are non-existence. Although some techniques (e.g. satellite, undersea fiber, microwave communication) have been used in marine communication, they are either too expensive with very small bandwidth, or too limited in its coverage range. We propose to develop a marine wireless mesh network which is formed by low cost buoyed wireless base stations to provide broadband connectivity for users on the sea.
Ocean wave simulation and prediction are key technologies in developing marine mesh network, because marine environments are dramatically different from terrestrial environment. The ocean waves have characteristics of rhythmic oscillations and the line of sight between two communication nodes is often blocked by them. Therefore, we have to develop a new wave-state-aware networking protocol which is suitable for marine environments. Ocean wave simulation technology can simulate this kind of dynamic environments and provide a test platform for the development of marine mesh network. Ocean wave prediction technology can improve the throughput of marine wireless network. Thus, they are indispensable technologies in developing marine mesh network.
In this thesis, we designed an ocean wave measurement method, two ocean wave prediction methods, and an ocean wave simulation method.
Firstly, we designed an accelerometer-based ocean wave measurement method. It can measure the real time wave height accurately.
Secondly, we designed an Elman-neural-network-based ocean wave prediction method for nonlinear waves. It has a higher prediction accuracy than other neural network methods in nonlinear wave prediction.
Thirdly, we designed a multiple-linear-regression-based ocean wave prediction method for linear waves. It has a higher prediction accuracy and less time consumption than other methods in linear wave prediction.
Finally, we implemented and improved a spectrum-based ocean wave simulation method which is originally proposed by Tessendorf. It can present the movement of ocean waves realistically and in real time.
To sum up, above four methods provide an effective test platform and technical support for the development of our marine mesh network. / Master of Science / With the development of wireless communication technology, WiFi has been an indispensable resource for daily work and pleasure. However, in the marine environments, WiFi is not exist. Thus, passengers and workers on the sea are eager for it. We propose to develop a marine wireless mesh network which is formed by low cost buoyed wireless base stations to provide WiFi for users on the sea.
Marine environments are dramatically different from terrestrial environments. The ocean waves have characteristics of rhythmic oscillations and the link between two buoys is often blocked. Therefore, the signals are also intermittent. We decided to develop a new wave-state-aware networking protocol to eliminate the harmful effect of this kind of rhythmic oscillations. Ocean wave simulation and prediction are key technologies in developing networking protocol, in which ocean wave simulation technology can simulate the marine environments and provide a test platform for developing networking protocol. Ocean wave prediction technology can improve the network throughput. Thus, they are indispensable technologies in developing marine mesh network.
In this thesis, we mainly research three problems that related to ocean waves, they are ocean wave measurement, ocean wave prediction and ocean wave simulation. Ocean wave measurement can tell us the current wave height of a buoy, ocean wave prediction can tell us the future height of a buoy, after we know these information, we can decide whether allow the buoy to send signal. It can not only save energy, but also improve the success rate of communication. Ocean wave simulation can provide us a dynamic environment to test whether our networking protocol works well.
To sum up, these methods provide an effective test platform and technical support for the development of our marine mesh network.
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Sensitivity of the EQ-5D-5L for fatigue, memory and concentration problems, and dyspnea, and their added value in patients after COVID-19 with persistent long-term symptoms : - An application of multiple linear regression and LASSOWadsten, Carl January 2023 (has links)
This thesis examined the sensitivity of the EQ-5D-5L instrument in measuring health-related quality of life (HRQoL) among patients with persistent symptoms following COVID-19, including fatigue, memory and concentration problems, and dyspnea. Additionally, it was analyzed whether adding these symptoms to the EQ-5D-5L improved the explained variance for HRQoL. Patients from Uppsala University Hospital, Sweden, answered a survey that included questions on five dimensions of health represented by the EQ-5D-5L and an additional question on general health score called EQ-VAS. Multiple linear regression, Spearman’s rank correlation coefficient, and Least Absolute Shrinkage and Selection Operator (LASSO) were used to examine the sensitivity of the EQ-5D-5L. For the explanatory analysis, the Adjusted 𝑅2 was used to evaluate explanatory power with and without the presence of the symptoms. The results showed that the EQ-5D-5L dimensions explained a moderate proportion of the variance for fatigue and memory/concentration problems and a weak proportion for dyspnea. The explanatory analysis provided findings that fatigue significantly improved the explained variance of EQ-VAS by 5.5%, adding memory/concentration problems only improved it marginally, and adding dyspnea was non-significant. Additionally, strong to moderate correlations between fatigue and memory/concentration problems were found with multiple dimensions of the EQ-5D-5L. These findings suggest that the EQ-5D-5L instrument may be a valuable tool in assessing HRQoL in patients with persistent COVID-19 symptoms and that adding fatigue to the EQ-5D-5L could be beneficial for improving explanatory power to HRQoL in patients suffering from infectious disease. / COMBAT post-covid
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博弈產業與澳門經濟發展—「自由行」實施前後之比較 / The relationship between gambling industry and economic development of Macau: A comparison before and after the implementation of “Free Trip”王智樺 Unknown Date (has links)
1999年澳門回歸中國大陸後,博弈產業成為澳門經濟發展的龍頭。近十年來,伴隨著澳門人均GDP上升、博弈產業的豐厚利潤、政府稅收逐年提升等經濟急速發展的現象,使得澳門模式成為東亞國家競相模仿的對象,而博弈產業是否造成地方經濟產業單一化,或是帶動其他產業齊頭式發展,也是各界爭論的議題。特別在澳門與中國簽訂《內地與澳門關於建立更緊密經貿關係的安排》(CEPA)後,由於開放內地遊客「自由行」政策,使得博弈產業錦上添花。為了清楚瞭解博弈產業對澳門經濟發展到底造成何種影響,本文主要研究目的有以下兩點:一為探討博弈產業是否對澳門人均GDP是否造成影響,二為比較在「自由行」政策實施前後,博弈產業對澳門經濟的影響。
根據實證結果顯示,博彩消費、人口、公共支出、CEPA的簽訂,皆與澳門人均GDP呈現正向關係,證明了博弈產業的確影響澳門經濟發展甚大。但研究結果也顯示,博弈產業在「自由行」實施後,對澳門經濟影響力反而下降,因此本研究推論,在「自由行」實施前,澳門經濟大部分靠博彩業支撐,其他產業積弱不振;「自由行」實施後,其他產業得到發展機會,增長速度超越博彩業發展的速度,才會造成本研究實證結果。
總的來說,博彩業在澳門與中國簽訂CEPA後,反而減弱其影響力,表示在「自由行」實施後,其他產業並沒有隨著博彩業的壯大而消失,反而跟著博彩業一同成長,澳門產業結構並無朝向單一化,反而更加多元。帶動其他行業發展,有利建設先進、多元化的綜合城市。 / The gambling industry has become the leading industry in Macau since Macau return to China in 1999. This decade, accompanying with the rise of Macau’s GDP per capita, the huge profits the gambling industry, such as the phenomenon of rapid economic growth, making “Macau Pattern” become a model which East Asian countries compete to imitate. It is a controversial issue that if the gambling industry made the local industry more singlize or led other industry develop. Especially after Macao and China signed the "Mainland and Macao Closer Economic Partnership Arrangement" (CEPA), the opening up of the Mainland visitors as a result of "Free Trip" policy, helping the gambling industry develop rapidly. In order to clearly understand the game industry how to impact Macao's economic development, the purposes are to investigate the relationship between gambling industry and economic development of Macau.
The empirical result shows: gambling consumption, population, public expenditure and CEPA signing have significant positive effects on economic development in Macau, Proving that the impact of the game industry is indeed a great economic development of Macau. The result also shows that after the signing of CEPA, gambling industry has fewer impact on economic development in Macau. Therefore, we infer that all industries except gambling industry were weak before “Free Trip”, and other industry got chance to develop after “Free Trip”.
To sum up, the gambling industry is the main industry that affects the economic development in Macau. After “Free Trip”, other industries didn’t disappear or decline, all of them keep developing with gambling industry.
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Trångboddhet i OECD : En jämförande tvärsnittsstudie om trångboddhetNykvist, Lucas January 2017 (has links)
Denna uppsats försöker besvara frågan: Vad förklarar skillnader i trångboddhet mellan OECD:s medlemsländer? Detta görs genom tvärsnittsstudie där jag analyserar vilken effekt faktorerna Hyresreglering, Reglering av byggbranschen, Demografiska förändringar, Styrande regeringsparti och Välstånd har på Trångboddheten. Tjugonio av OECD:s medlemsländer har tagits med i analysen. Med hjälp av en multipel linjär regression baserat på observationsdata från variablerna presenteras resultaten. Slutsatserna är att Reglering av byggbranschen och Välstånd har störst effekt på Trångboddheten. / This paper attempts to answer the research question: What explains the differences in housing density between the members of the OECD? This is done by a cross-sectional study in which I analyze the impact of rent regulation, regulation of the construction industry, demographic changes, executive government party and wealth has on the dependent variable housing density. Twenty-nine of the OECD members have been included in the analysis. The paper is using a multiple linear regression to analyze the results. The conclusions are that the regulation of the construction industry and wealth has the greatest effect on housing density.
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An exploratory analysis of convoy protection using agent-based simulationHakola, Matthew B. 06 1900 (has links)
Approved for public release, distribution is unlimited / Recent insurgent tactics during Operation Iraqi Freedom (OIF) have demonstrated that coalition logistical convoys are vulnerable targets. This thesis examines the tactics, techniques and procedures (TTPs) used in convoy operations in an attempt to identify the critical factors that lead to mission success. A ground convoy operation scenario is created in the agentbased model (ABM) Map Aware Non-uniform Automata (MANA). The scenario models a generic logistical convoy consisting of security vehicles, logistical vehicles, an unmanned aerial vehicle (UAV) and an enemy ambushing force. The convoy travels along a main supply route (MSR) where it is ambushed by a small insurgent force. We use military experience, judgment and exploratory simulation runs to identify 11 critical factors within the created scenario. The data farming process and Latin Hypercube (LHC) experimental design technique are used to thoroughly examine the 11 factors. Using the 11 factors 516 design points are created and data farmed over to produce 25,800 observations. Additive multiple linear regression is used to fit a model to the 25,800 observations. From the created scenario it is concluded that: convoy mission success may be determined by only a few factors; the actions of logistical vehicles are more critical than those of security vehicles; UAVs provide a statistically significant advantage; and ABMs coupled with LHCs and data farming are valuable tools for understanding complex problems. / Captain, United States Marine Corps
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Einführung in die ÖkonometrieHuschens, Stefan 30 March 2017 (has links) (PDF)
Die Kapitel 1 bis 6 im ersten Teil dieses Skriptes beruhen auf einer Vorlesung Ökonometrie I, die zuletzt im WS 2001/02 gehalten wurde, die Kapitel 7 bis 16 beruhen auf einer Vorlesung Ökonometrie II, die zuletzt im SS 2006 gehalten wurde. Das achte Kapitel enthält eine komprimierte Zusammenfassung der Ergebnisse aus dem Teil Ökonometrie I.
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Impact of Combat Stress on Mental Health Outcomes: BRFSS Survey Data 2006Pedneau, Emily 01 January 2007 (has links)
Objectives: This study sought to determine the relationship between combat experience and mental health outcomes. The study sought to determine whether age was a significant factor in poor mental health outcomes. Methods: Multiple logistic regression (n = 195,048) and multiple linear regression (n = 264,154) were performed on the 2006 Behavioral Risk Factor Surveillance System (BRFSS) survey. Veteran status and a host of demographic and health status questions were analyzed in relation to diagnosis of anxiety or depressive disorder (multiple logistic regression) and to number of days poor mental health (multiple linear regression). Results: Diagnosis of anxiety or depression was not found to be associated with veteran status. Among both veterans and non-veterans, diagnosis was associated with age Conclusions: Contrary to expectations, veteran status was found to be a protective factor for poor mental health outcomes in this analysis. Younger age was found to be associated with poor mental health outcomes, but was an equal association in both veterans and non-veterans, suggesting that mental health outcomes have not been worsened by recent changes in combat characteristics. Denial of mental health status, stoicism within the military community, and limitations of the survey are proposed to explain the unexpected outcome of this analysis.
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