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An Investigation into the Relationship Between Economic Growth, Energy Consumption, and the Environment: Evidence from NigeriaAhmad, Ahmad January 2023 (has links)
This thesis employs the Autoregressive Distributed Lag model (ARDL), Toda-Yamamoto causality analysis, and ordinary least square (OLS for robust estimation) techniques to empirically investigate the impact of economic growth and energy consumption on the environment in Nigeria from 1980 to 2020. The results of cointegration demonstrate a long-term link between the model's input variables. The outcome of the first objective of the study shows that trade and economic development in Nigeria worsen the state of the environment. Environmental quality is accelerated by financial development; nevertheless, FDI is proven to be insignificant in predicting environmental quality. The result demonstrates that FDI and energy use both have the potential to significantly speed up the rate of environmental degradation. Nevertheless, trade has a negligible impact on the environment in the country, and financial development slows down environmental deterioration. The study also finds that the combination between energy and economic development improves Nigeria's environmental quality. The outcome of the fourth objective shows that economic expansion and energy consumption have a favorable impact on the environment. Additionally, environmental degradation, energy use, and economic growth are all causally related. Moreover, the outcome of the robust estimation reveals a positive and significant relationship between economic growth and energy consumption in the environment.
Therefore, the study suggests economic policies with environmental control measures. This could be through an emphasis on the use of other alternatives of low-emission energy, that will mitigate the level of C02 and enhance energy utilization for a better environment in the nation.
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Validation and Optimization of Hyperspectral Reflectance Analysis-Based Predictive Models for the Determination of Plant Functional Traits in Cornus, Rhododendron, and SalixValdiviezo, Milton I 01 January 2020 (has links)
Near infrared spectroscopy (NIR) has become increasingly widespread throughout various fields as an alternative method for efficiently phenotyping crops and plants at rates unparalleled by conventional means. With growing reliability, the convergence of NIR spectroscopy and modern machine learning represent a promising methodology offering unprecedented access to rapid, high throughput phenotyping at negligible costs, representing prospects that excite agronomists and plant physiologists alike. However, as is true of all emergent methodologies, progressive refinement towards optimization exposes potential flaws and raises questions, one of which is the cornerstone of this study. Spectroscopic determination of plant functional traits utilizes plants' morphological and biochemical properties to make predictions, and has been validated at the community (inter-family) and individual crop (intraspecific) levels alike, yielding equally reliable predictions at both scales, yet what lies amid these poles on the spectrum of taxonomic scale remains unexplored territory. In this study, we replicated the protocol used in studies of the aforementioned taxonomic scale extremes and applied it to an intermediate scale. Interestingly, we found that predictive models built upon hyperspectral reflectance data collected across three genera of woody plants: Cornus, Rhododendron, and Salix, yielded inconsistent predictions of varying accuracy within and across taxa. Identifying the potential cause(s) underlying variability in predictive power at this intermediate taxonomic scale may reveal novel properties of the methodology, potentially permitting further optimization through careful consideration.
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Determining Intersection Turning Movements with Detection ErrorsFeng, Dehua January 2017 (has links)
No description available.
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Improvement of Bacteria Detection Accuracy and Speed Using Raman Scattering and Machine LearningMandour, Aseel 15 September 2022 (has links)
Bacteria identification plays an essential role in preventing health complications and saving patients' lives. The most widely used method to identify bacteria, the bacterial cultural method, suffers from long processing times. Hence, an effective, rapid, and non-invasive method is needed as an alternative. Raman spectroscopy is a potential candidate for bacteria identifi cation due to its effective and rapid results and the fact that, similar to the uniqueness of a human fingerprint, the Raman spectrum is unique for every material.
In my lab at the University of Ottawa, we focus on the use of Raman scattering for
biosensing in order to achieve high identifi cation accuracy for different types of bacteria.
Based on the unique Raman fingerprint for each bacteria type, different types of bacteria can be identifi ed successfully. However, using the Raman spectrum to identify bacteria poses a few challenges. First, the Raman signal is a weak signal, and so enhancement of the signal intensity is essential, e.g., by using surface-enhanced Raman scattering (SERS).
Moreover, the Raman signal can be contaminated by different noise sources. Also, the signal consists of a large number of features, and is non-linear due to the correlation between the Raman features. Using machine learning (ML) along with SERS, we can overcome such challenges in the identifi cation process and achieve high accuracy for the system identifying bacteria.
In this thesis, I present a method to improve the identifi cation of different bacteria
types using a support vector machine (SVM) ML algorithm based on SERS. I also present dimension reduction techniques to reduce the complexity and processing time while maintaining high identifi cation accuracy in the classifi cation process. I consider four bacteria types: Escherichia coli (EC), Cutibacterium acnes (CA, it was formerly known as Propi-onibacterium acnes), methicillin-resistant Staphylococcus aureus (MRSA), and methicillin-sensitive Staphylococcus aureus (MSSA). Both the MRSA and MSSA are combined in a single class named MS in the classifi cation. We are focusing on using these types of bacteria as they are the most common types in the joint infection disease.
Using binary classi fication, I present the simulation results for three binary models: EC
vs CA, EC vs MS, and MS vs CA. Using the full data set, binary classi fication achieved a classi fication accuracy of more than 95% for the three models. When the samples data set was reduced, to decrease the complexity based on the samples' signal-to-noise ratio (SNR), a classi fication accuracy of more than 95% for the three models was achieved using less than 60% of the original data set. The recursive feature elimination (RFE) algorithm was then used to reduce the complexity in the feature dimension. Given that a small number of features were more heavily weighted than the rest of the features, the number of features used in the classifi cation could be signi ficantly reduced while maintaining high classi fication accuracy.
I also present the classifi cation accuracy of using the multiclass one-versus-all (OVA)
method, i.e., EC vs all, MS vs all, and CA vs all. Using the complete data set, the OVA
method achieved classi cation accuracy of more than 90%. Similar to the binary classifi cation, the dimension reduction was applied to the input samples. Using the SNR reduction, the input samples were reduced by more than 60% while maintaining classifi cation accuracy higher than 80%. Furthermore, when the RFE algorithm was used to reduce the complexity on the features, and only the 5% top-weighted features of the full data set were used, a classi fication accuracy of more than 90% was achieved. Finally, by combining both reduction dimensions, the classi fication accuracy for the reduced data set was above 92% for a signifi cantly reduced data set.
Both the dimension reduction and the improvement in the classi fication accuracy between different types of bacteria using the ML algorithm and SERS could have a signi ficant impact in ful lfiling the demand for accurate, fast, and non-destructive identi fication of bacteria samples in the medical fi eld, in turn potentially reducing health complications and saving patient lives.
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Determination of fertility rating (FR) in the 3-PG model for loblolly pine (Pinus taeda L.) plantations in the southeastern United StatesSubedi, Santosh 22 May 2015 (has links)
Soil fertility is an important component of forest ecosystem, yet evaluating soil fertility remains one of the least understood aspects of forest science. Phytocentric and geocenctric approaches were used to assess soil fertility in loblolly pine plantations throughout their geographic range in the United States. The model to assess soil fertility using a phytocentric approach was constructed using the relationship between site index and aboveground productivity. Geocentric models used physical and chemical properties of the A-horizon. Soil geocentric models were constructed using two modeling approaches. In the first approach, ordinary least squares methods of multiple regression were used to derive soil fertility estimated from site index using soil physical and chemical properties from the A-horizon. Ordinary least squares methods were found unsuitable due to multicollinearity among the soil variables. In the second approach, a multivariate modeling approach, partial least squares regression, was used to mitigate multicollinearity effects. The best model to quantify soil fertility using soil physical and chemical properties included N, Ca, Mg, C, and sand percentage as the significant predictors. The 3-PG process-based model was evaluated for simulating the response of loblolly pine to changes in soil fertility. Fertility rating (FR) is a parameter in 3-PG that scales soil fertility in the range of 0 to 1. FR values estimated from phytocentric and geocentric approaches were tested against observed production. The 3-PG model prediction of aboveground productivity described 89% percent of the variation in observed aboveground productivity using FR derived from site index and 84% percent of the vari- ation in observed aboveground productivity using FR derived from physical and chemical properties of the A-horizon. A response function to model dynamics of FR (∆FR) due to one time midrotatoin fertilization of N and P was developed using the Weibull function. The magnitude of ∆FR varied with intensity of N and time since application of fertilizer. The hypothesis that repeated fertilization with N and P eliminate major nutrient deficiency in the southeastern US was tested and a relationship between baseline fertility rating and fertilizer response was developed. An inverse relationship was observed between fertilizer response and baseline FR. / Ph. D.
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The relationship between inflation and economic growth in EthiopiaAbis Getachew Makuria 14 July 2014 (has links)
The main purpose of this study is to empirically assess the relationship between inflation
and economic growth in Ethiopia using quarterly dataset from 1992Q1 to 2010Q4. In
doing so, an interesting policy issue arises. What is the threshold level of inflation for the
Ethiopian economy? Based on the Engle-Granger and Johansen co-integration tests it is
found out that there is a positive long-run relationship between inflation and economic
growth. The error correction models show that in cases of short-run disequilibrium, the
inflation model adjusts itself to its long-run path correcting roughly 40% of the
imbalance in each quarter. In addition, based on the conditional least square technique,
the estimated threshold model suggests 10% as the optimal level of inflation that
facilitates growth. An inflation level higher or lower than the threshold level of inflation
affects the economic growth negatively and hence fiscal and monetary policy
coordination is vital to keep inflation at the threshold. / Economics / M. Com. (Economics)
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台灣股票市場風險溢酬之星期效應實證研究 / The Day-of-the-Week Effect of the Equity Risk Premium: Evidence from the Taiwan Stock Exchange江佶明, Chiang,Chi-ming Unknown Date (has links)
近年來的研究顯示英美兩國的無風險利率存在著星期效應,但其股市報酬率的星期效應卻逐漸消失、甚至有反轉,因此本研究想探討台灣加權股價指數報酬率與無風險利率,是否存在著星期效應,抑或跟隨英美兩國的腳步,星期效應不再。此外,本研究亦探討風險溢酬的星期效應,試圖從中解開風險溢酬之謎(Equity Risk Premium)。
行政院於1998年至2000年實施「公務人員每月二次週休二日實施計劃」,台灣股票市場因此實施隔週休二日的制度,這特別的休市制度正好提供本研究進行交割效應假說所需的特殊樣本。認售權證正式於2003年7月上市掛牌買賣,因此去年下半年開始發行的認售權證交易量,亦正好提供本研究檢定投機放空假說所需的樣本。
實證結果顯示,大盤指數報酬率與風險溢酬有顯著的星期效應與週末效應,一週之中每日的報酬率並不相等,其中以週五與週六為最高,有顯著為正的報酬。而週一與週二平均報酬率為負但不顯著。而無風險利率有顯著的星期效應,但週末效應卻不顯著,一週之中每日的利率雖不相等但均顯著異於零。
更進一步探究報酬率、風險溢酬之星期效應與週末效應的成因,發現此星期效應、週末效應支持資訊處理假說、正向回饋假說與投機放空假說;但是卻不支持交割效應假說淤測量錯誤假說。因此得知台灣股票市場報酬率與風險溢酬之星期效應與週末效應的成因,乃為投資人在工作日與非工作日資訊處理成本的差異而導致;此外,過多的融券交易量亦為造成星期效應與週末效應的成因之一。
關鍵詞:星期效應、週末效應、風險溢酬、TLS模型、Power Ratio
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An adaptive autopilot design for an uninhabited surface vehicleAnnamalai, Andy S. K. January 2014 (has links)
An adaptive autopilot design for an uninhabited surface vehicle Andy SK Annamalai The work described herein concerns the development of an innovative approach to the design of autopilot for uninhabited surface vehicles. In order to fulfil the requirements of autonomous missions, uninhabited surface vehicles must be able to operate with a minimum of external intervention. Existing strategies are limited by their dependence on a fixed model of the vessel. Thus, any change in plant dynamics has a non-trivial, deleterious effect on performance. This thesis presents an approach based on an adaptive model predictive control that is capable of retaining full functionality even in the face of sudden changes in dynamics. In the first part of this work recent developments in the field of uninhabited surface vehicles and trends in marine control are discussed. Historical developments and different strategies for model predictive control as applicable to surface vehicles are also explored. This thesis also presents innovative work done to improve the hardware on existing Springer uninhabited surface vehicle to serve as an effective test and research platform. Advanced controllers such as a model predictive controller are reliant on the accuracy of the model to accomplish the missions successfully. Hence, different techniques to obtain the model of Springer are investigated. Data obtained from experiments at Roadford Reservoir, United Kingdom are utilised to derive a generalised model of Springer by employing an innovative hybrid modelling technique that incorporates the different forward speeds and variable payload on-board the vehicle. Waypoint line of sight guidance provides the reference trajectory essential to complete missions successfully. The performances of traditional autopilots such as proportional integral and derivative controllers when applied to Springer are analysed. Autopilots based on modern controllers such as linear quadratic Gaussian and its innovative variants are integrated with the navigation and guidance systems on-board Springer. The modified linear quadratic Gaussian is obtained by combining various state estimators based on the Interval Kalman filter and the weighted Interval Kalman filter. Change in system dynamics is a challenge faced by uninhabited surface vehicles that result in erroneous autopilot behaviour. To overcome this challenge different adaptive algorithms are analysed and an innovative, adaptive autopilot based on model predictive control is designed. The acronym ‘aMPC’ is coined to refer to adaptive model predictive control that is obtained by combining the advances made to weighted least squares during this research and is used in conjunction with model predictive control. Successful experimentation is undertaken to validate the performance and autonomous mission capabilities of the adaptive autopilot despite change in system dynamics.
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Control of a Multivariable Lighting SystemHalldin, Axel January 2017 (has links)
This master’s thesis examines how a small MIMO lighting system can be identified and controlled. Two approaches are examined and compared; the first approach is a dynamic model using state space representation, where the system identification technique is Recursive Least Square, RLS, and the controller is an LQG controller; the second approach is a static model derived from the physical properties of light and a feedback feed-forward controller consisting of a PI controller coupled with a Control Allocation, CA, technique. For the studied system, the CA-PI approach significantly outperforms the LQG-RLS approach, which leads to the conclusion that the system’s static properties are predominant compared to the dynamic properties.
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The relationship between inflation and economic growth in EthiopiaAbis Getachew Makuria 14 July 2014 (has links)
The main purpose of this study is to empirically assess the relationship between inflation
and economic growth in Ethiopia using quarterly dataset from 1992Q1 to 2010Q4. In
doing so, an interesting policy issue arises. What is the threshold level of inflation for the
Ethiopian economy? Based on the Engle-Granger and Johansen co-integration tests it is
found out that there is a positive long-run relationship between inflation and economic
growth. The error correction models show that in cases of short-run disequilibrium, the
inflation model adjusts itself to its long-run path correcting roughly 40% of the
imbalance in each quarter. In addition, based on the conditional least square technique,
the estimated threshold model suggests 10% as the optimal level of inflation that
facilitates growth. An inflation level higher or lower than the threshold level of inflation
affects the economic growth negatively and hence fiscal and monetary policy
coordination is vital to keep inflation at the threshold. / Economics / M. Com. (Economics)
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