Šio magistrinio darbo tikslas yra atskleisti pajamų iš individualios veiklos apmokestinimo Lietuvoje teorines ir praktines problemas. Pagrindinis dėmesys skiriamas pajamų iš individualios veiklos koncepcijai, nagrinėjant pačios individualios veiklos sąvoką, taip pat apmokestinimo teisiniam reglamentavimui, individualios veiklos buhalterinei apskaitai ir deklaracijų teikimui. Apmokestinant asmens pajamas iš individualios veiklos pirmiausia reikia nustatyti, ar asmuo vykdo tokią veiklą. Individualiai veiklai nepriklauso darbo veikla, t.y. kai asmuo tam tikrą laiką kito asmens naudai ir jo pavaldume atlieka paslaugas už tai gaudamas atlygį. Taip pat atsitiktinio pobūdžio asmens komerciniai sandoriai, vienkartiniai veiksmai. Individualios veiklos pajamos priskiriamos B klasei. Pajamų mokestį nuo šių pajamų nuolatinis Lietuvos gyventojas deklaruoja, apskaičiuoja ir sumoka pasibaigus mokestiniam laikotarpiui, neatsižvelgiant į tai, kad mokestiniame laikotarpyje kurį laiką veiklos nevykdė ir pajamų negavo. Kita vertus, kai gyventojas pageidauja, mokestiniu laikotarpiu jis gali apskaičiuoti pagal GPMĮ nuostatas nuo tokių pajamų priklausančią mokėti pajamų mokesčio sumą ir šį mokestį sumokėti, mokestiniu laikotarpiu neteikdamas jokios deklaracijos. Lietuvos gyventojo užsienyje gautos pajamos ir yra apmokestinamos užsienio valstybėje, o Lietuvoje jos yra atleidžiamos nuo mokesčio. / The main idea of this scrutiny is to outline the scope of taxable income from individual activity in Lithuania. The survey deals first with questions of notion of individual activity in Lithuanian personal income tax law, then with the calculation rules and principles, characteristics of taxable income, also declaration of income from individual activity is discussed. If income from individual activity must be taxed, first individual activity shall be determined. Individual activity varies from employment relations, i.e. when a person does his actual work under the subordination of someone else and gets renumeration. Also accasionally actions do not constitute individual activity. Income from individual activity form income of class B. Taxes from such an activity shall be declared, calculated and paid by the taxpayer until the first of May of next year. Income of Lithuanian resident received in foreigh country are not taxed by Lithuanian laws rather by that country where it was earned.

Availability of precipitation data is very important in every aspect related to hydrology. Readings from the ground stations are reliable and are used in hydrological models to do various analysis. However, the predictions are always associated with uncertainties due to the limited number of ground stations, which requires interpolation of the data. Meanwhile, groundbreaking approach in capturing precipitation events from vantage point through satellites in space has created a platform to not only merge ground data with satellite estimates to produce more accurate result, but also to find the data where ground stations are not available or scarcely available. Nevertheless, the data obtained through these satellite missions needs to be verified on its temporal and spatial resolution as well as the uncertainties associated before we make any decisions on its basis. This study focuses on finding and evaluating data obtained from two multi-satellite precipitation measurements missions: i) Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) ii) Global Precipitation Measurement (GPM) mission. GPM is the latest mission launched on Feb 28, 2014 after the successful completion of TRMM mission which collected valuable data for 17 years since its launch in November 1997. Both near real time and final version precipitation products for TMPA and GPM are considered for this study. Two study areas representing eastern and western parts of the United States of America (USA) are considered: i) Charlotte (CLT) in North Carolina ii) San Francisco (SF) in California. Evaluation is carried out for daily accumulated rainfall estimates and single rainfall events. Statistical analysis and error categorization of daily accumulated rainfall estimates were analyzed in two parts: i) Ten yeas data available for TMPA products were considered for historical analysis ii) Both TMPA and GPM data available for a ten-month common period was considered for GPM Era analysis. To study how well the satellite estimates with their finest temporal and spatial resolution capture single rainfall event and to explore their engineering application potential, an existing model of SF watershed prepared in Infoworks Integrated Catchment Model (ICM) was considered for hydrological simulation. Infoworks ICM is developed and maintained by Wallingford Software in the UK and SF watershed model is owned by San Francisco Public Works (SFPW). The historical analysis of TMPA products suggested overestimation of rainfall in CLT region while underestimation in SF region. This underestimation was largely associated with missed-rainfall events and negative hit events in SF. This inconsistency in estimation was evident in GPM products as well. However, in the study of single rainfall events with higher magnitude of rainfall depth in SF, the total rainfall volume and runoff volume generated in the watershed were over-estimated. Hence, satellite estimates in general tends to miss rainfall events of lower magnitude and over-estimate rainfall events of higher magnitude. From statistical analysis of GPM Era data, it was evident that GPM has been able to correct this inconsistency to some extent where it minimized overestimation in CLT region and minimized negative error due to underestimation in SF. GPM products fairly captured the hydrograph shape of outflow in SF watershed in comparison to TMPA. From this study, it can be concluded that even though GPM precipitation estimates could not quiet completely replace ground rain gage measurements as of now, with the perpetual updating of algorithms to correct its associated error, it holds realistic engineering application potential in the near future.

Bakalauro baigiamąjame darbe atskleidžiama tiesioginių mokesčių vieta Lietuvos mokesčių sistemoje, išskiriant mokesčių rūšis priskiriamas prie tiesioginių mokesčių grupės, nagrinėjami GPM, pelno mokesčio ir turto mokesčių (nekilnojamojo turto mokesčio, žemės mokesčio, paveldimo turto mokesčio) apmokestinimo instrumentarijai. Nagrinėjama nacionalinio biudžeto mokestinių pajamų struktūrą, dinamika 2006-2010 m., atskleidžiama pajamų iš tiesioginių mokesčių lyginamieji svoriai nacionalinio biudžeto mokestinių pajamų struktūroje. Atliktas pajamų iš GPM, pelno mokesčio, turto mokesčių tyrimas, kurio metu atskleidžiama pajamų iš GPM, pelno mokesčio, turto mokesčių dinamika 2006-2010 m. pajamų iš GPM, pelno mokesčio, turto mokesčių surinkimo plano vykdymas, įdentifikuoti veiksniai įtakojantys pajamų iš GPM, pelno mokesčio, turto mokesčių kitimo tendencijos, atskleistos pajamų iš GPM pagal apmokestinimo objektus, pajamų iš pelno mokesčio pagal įmonių rūšis ir pajamų iš turto mokesčių pagal mokesčių rūšis kitimo tendencijos. Taip pat įdentifikuotos pajamų iš tiesioginių mokesčių didinimo galimybės. / Bachelor of baigiamąjame disclosure of direct taxes in the work of the tax system, excluding tax type assigned to direct tax group, deal with gpm, corporation tax and wealth tax (real estate tax, tax, inheritance tax) instrumentarijai taxation. The national budget tax income structure, dynamics 2006-2010, disclosed the revenue from direct taxes weighting national budget of tax revenue. A revenue from gpm, income tax, wealth tax trial, disclosed the revenue from gpm, income tax, wealth tax dynamics 2006-2010. revenue from gpm of income tax, wealth tax collection plan execution, įdentifikuoti factors contributing to income from gpm, income tax, wealth tax trends, disclosed the taxation of income from gpm objects, revenue from income tax by the undertakings and the types of property income tax by tax type trends. Also įdentifikuotos revenue from direct tax increases.

Les précipitations résultent d'un phénomène atmosphérique caractérisé par une variabilité spatiale et temporelle forte. Cette variabilité dans la distribution des pluies et des évènements intenses a des impacts en hydrologie de surface (e.g. inondations) variés selon les régions du monde. Toute modification du climat tropical est associée à une modification du cycle de l'eau et de l'énergie dans ces régions. Dans un contexte de changement climatique, il est donc important de développer des outils permettant d'estimer quantitativement les précipitations, à l'échelle du globe, à la fois sur les surfaces continentales et les surfaces océaniques. Les travaux présentés dans cette thèse s'intéressent à l'observation des précipitations depuis l'espace. En effet, la mesure des pluies nécessite une densité d'observations élevée qui, sur l'ensemble des Tropiques, n'est accessible qu'à partir d'observations spatiales. Depuis plusieurs décades, les moyens satellitaires à disposition ont beaucoup évolué et offrent aujourd'hui une densité d'observations de plus en plus fortes. Grâce aux nouvelles missions déployées telles que Megha-Tropiques au sein de la future constellation GPM (Global Precipitation Measurement), on a accès à un ensemble de systèmes d'observations qui amène à une densité accrue d'observations spatiales. L'estimation quantitative des précipitations n'était possible qu'à l'échelle mensuelle, il est maintenant envisageable d'estimer la pluie par satellite à des échelles de temps de plus en plus fines. Cette thèse s'intéresse aux échelles 1°/1-jour, échelle clé pour les études météorologiques et hydrologiques. Il existe un large spectre de méthodes d'estimations de précipitations par satellite, de qualité inégale. Dans un premier temps, une analyse des produits issus des développements les plus récents montre que leur qualité a atteint un degré suffisant pour être utilisé de manière quantitative aux échelles de temps pertinentes en météorologie. Il apparaît également qu'à ces échelles de temps, il est nécessaire d'utiliser les estimations de cumul de précipitations conjointement avec leurs barres d'erreurs. Une nouvelle méthode d'estimations de précipitations sur l'ensemble de la ceinture tropicale, appelé TAPEER (Tropical Amount of Precipitation with an Estimate of ERrors), est donc développée dans le but d'estimer des cumuls de pluie et leurs erreurs associées à l'échelle 1°/1-jour. Cette approche est fondée sur une méthode de fusion de données de l'imagerie Infrarouge d'une constellation de satellites géostationnaires et d'estimations de taux de pluie issues de radiomètres Micro-ondes d'une constellation de satellites défilant. Des techniques modélisations sont mises en oeuvre afin d'associer une erreur aux cumuls de pluie produits. Une investigation détaillée du bilan d'erreur de la méthode TAPEER montre que les sources principales d'incertitudes sont liées à l'échantillonnage et aux biais systématiques sur les taux de pluie d'intensité moyenne. Une étude sur l'été 2009 révèle l'importance de l'utilisation de la barre d'erreur dans l'analyse de la distribution des pluies, en particulier pour les plus forts cumuls sur la ceinture tropicale / Precipitation results from atmospheric phenomena, which are characterized by a large space and time variability. The distribution of rainfall, in particular of strong rainy events, has various impacts in surface hydrology over the different regions in the world (e.g. floods). Any change in the Tropical climate is associated with a modification of the water and energy cycle over those regions. Therefore, in a context of climate change, it is important to develop new tools able to provide quantitative precipitation measurements, both over land and over the open oceans. The work presented hereafter deals with precipitation estimation from space. Indeed, measuring rainfall requires a high density of observations, which, over the whole tropical belt, can only be provided from space. For several decades, the availability of satellite observations has greatly increased and offers an increasing number of measurements. Thanks to newly implemented missions like the Megha-Tropiques mission and the forthcoming GPM constellation (Global Precipitation Measurement mission), measurements from space become available from a set of observing systems. Quantitative precipitation estimation were only available at the monthly scale, it is now possible to estimate rainfall from space at increasingly fine scale. In this work, we focus on the 1°/1-day scale, key scale of meteorological and hydrological studies. Various methods exist to estimate rainfall from space but they provide estimates of unequal quality. First, a meteorological benchmark is set up with ground-based observations from the African Monsoon Multidisciplinary Analysis (AMMA) program. The analysis shows that the last generation of combined infrared-microwave products is describing the variability of rainfall similarly to ground measurements at meteorologically relevant scales. It also appeared that at these scales, rain accumulation estimations should be used taking into account their uncertainties. A novel methodology for quantitative precipitation estimation is introduced ; its name is TAPEER (Tropical Amount of Precipitation with an Estimate of ERrors) and it aims to provide 1°/1-day rain accumulations and associated errors over the whole Tropical belt. This approach is based on a combination of infrared imagery from a fleet of geostationary satellite and passive microwave derived rain rates from a constellation of low earth orbiting satellites. Modelling techniques are developed in order to associate an error with the individual rain accumulations. An investigation of the error budget of the TAPEER method shows that the two main contributions to the total error are related to sampling and systematic errors on rain rates of medium intensity. A study on the summer 2009 period reveals the importance of using error bars when analyzing the distribution of rainfall, especially for the most important rain accumulations of the tropics

This project served to analyze the effects that energy storage can have on energy production.  The study was aimed at Johannes CHP bio fuel. Johannes produces electricity for the SE3 region and heat for the district heating in Gävle. The electricity market is the main driving factor for energy production. It is ideal for Johannes to produce as much electricity as possible during high Elspot prices. Two accumulator tanks are already installed at Johannes so the surplus of heat can be stored from high electrical production. This study served to utilize the planning horizons for the future Elspot prices. The two forecasting methods presented are the 12 hour prices presented by Nord pool and the four day forecast predicted by ARIMA modeling. Several different energy storage technologies were theoretically discussed after which Gravity Potential Module, latent heat storage using phase change materials and open accumulator tanks were analyzed. The ideal system proved to be utilizing the four day ARIMA modeled forecast with a storage system consisting of Gravity Potential Module and latent heat storage. The system resulted in a gross profit of 1.4 million SEK and an increased average electrical production efficiency of .02% during 2011.

The scope of this project is to investigate if the software Ecolego is suitable for creating models in accordance with level 3 PSA, with the goal of creating a model calculating the possible outcomes for the radiological impact at 20 km distance resulting from a fictional severe nuclear accident at the Forsmark Nuclear Power Plant. This report aims to answer the questions “What is the concentration on the ground (kBq/m2), at a distance of 20 km, 30 days and 10 years after the fictional severe nuclear accident, with and without filtered venting” and “Is Ecolego a suitable software for level 3 PSA models?” The source term for the fictional severe nuclear accident is made to resemble the actual source term from the Fukushima Daiichi accident including the radionuclides Cs-134, Cs-136, Cs-137, I-131, I-132, I-133 and Te-132. In the model, three source terms are created and tested. Two source terms in which the total emissions are released in 24 hours, for which one contains the total emissions from the Fukushima Daiichi accident and one containing 1 percent of the emissions from the Fukushima Daiichi accident due to reduction of emissions when passing the filtered venting. The thirdsource term is made to resemble the time-dependent emissions for the Fukushima Daiichi accident, with emissions varying in intensity over 50 days. The transport of the radionuclide concentration is only due to atmospheric dispersion in the model, for which the Gaussian Plume Model (GPM) is applied under undisturbed condition where only the concentrations in the centerline of the plume are calculated. Probabilistic variation is performed with Monte Carlo simulations where probability density functions (PDFs) are assigned to wind speed andprecipitation, with 5000 iterations. Simulation of the model with one of the two source terms which has the release period of 24 hours gives reasonable results. However, to run the simulation with the time varying source term the model needs to be developed to generate reasonable results, for which necessary development actions are presented. The calculations of the resulting concentration on the ground 30 days and 10 years after the fictional accident shows that there are multiple possible outcomes, which makes it impossible to give a single answer to the expected concentration on the ground. Due to their short half-lives, there will be no concentrations of I-132 and I-133 on the ground at the distance 20 km after 30 days or 10 years. For the remaining radionuclides, the ranges of the possible outcomes for the concentration on ground are presented. It is concluded that Ecolego is suitable for PSA level 3 with the risk metric of environmental impact based on the results of the investigation. However, due to the time limit of the investigation, the applicability of creating an Ecolego model with the risk metrics health effects and economic impact are not investigated. But the report discusses suitable development of the model to contain the risk metric health effects in accordance with level 3 PSA. With such development the conclusion is that Ecolego is suitable for level 3 PSA.

La thèse s’inscrit dans le contexte de sûreté nucléaire relatif à l'hydruration des gainages combustibles en Zircaloy, en modélisant, à l’échelle atomique, les phénomènes d’ordre chimique hydrogène - lacune atomique, sur le sous-réseau interstitiel tétraédrique des hydrures de zirconium CFC. Une telle démarche s’est déclinée en deux étapes : en premier lieu, le développement d’un modèle énergétique atomistique à la fois précis et peu coûteux numériquement, puis l’implémentation d’approches thermostatistiques de type Monte-Carlo à l’aide de ce modèle. En prenant pour point de départ un Hamiltonien de Liaisons Fortes (TB), la construction du modèle énergétique a reposé sur la dérivation d’interactions multiatomiques entre atomes d’hydrogène, à l’aide de la méthode des perturbations généralisée (GPM) basée sur une représentation de l’état de désordre interstitiel dans l’Approximation du Potentiel Cohérent (CPA). La démarche a permis de réduire l'énergie d'ordre à un modèle d'Ising effectif dérivé des liaisons fortes (TBIM), basé sur les interactions de paires effectives entre atomes d’hydrogène. Le TBIM a ensuite été validé, en comparant les énergies de structures ordonnées d’une part reconstruites en TBIM, et d’autre part obtenues par des calculs directs d’énergie totale effectués soit en Liaisons Fortes, soit par des méthodes ab initio (DFT). L'implémentation d'une approche Monte-Carlo canonique par le TBIM a permis de caractériser les différentes transitions ordre-désordre, et d'établir un diagramme de phase de l’ordre chimique hydrogène - lacune atomique, sur le sous-réseau interstitiel tétraédrique des hydrures de zirconium CFC. / The thesis addresses the nuclear safety issue of Zircaloy fuel cladding hydruration, by modelling, at atomistic scale, chemical ordering processes between hydrogen and atomic vacancies on tetrahedral interstitial sublattice of CFC zirconium hydrides. This has been achieved into two steps : first the development of an atomistic energetic model sufficiently precise and not too much CPU time consuming, and secondly its implementation in Monte-Carlo thermostatistical simulations. Starting from a Tight-Binding (TB) Hamiltonian, the energetic model has been derived from the calculation of multiatomic interactions between hydrogen atoms, using the Generalized Perturbation Method (GPM) applied to an interstitial disorder described within the Coherent Potential Approximation (CPA). The path allows us to reduce the ordering energy to a Tight-Binding Ising Model (TBIM), based on effective pairwise interactions between hydrogen atoms. The TBIM has been validated by comparing ordering energies of ordered structures either reconstructed using TBIM, or directly obtained from total energy calculations perfor- med both within TB and ab initio (DFT) methods.By implementing a canonical Monte-Carlo with TBIM, we obtain different order-disorder phase transitions, and a phase diagram of H-vacancy chemical ordering, on the tetrahedral interstitial sublattice of CFC zirconium hydrides.

This work considers black-box Bayesian inference over high-dimensional parameter spaces. The well-known and widely respected adaptive Metropolis (AM) algorithm is extended herein to asymptotically scale uniformly with respect to the underlying parameter dimension, by respecting the variance, for Gaussian targets. The result- ing algorithm, referred to as the dimension-independent adaptive Metropolis (DIAM) algorithm, also shows improved performance with respect to adaptive Metropolis on non-Gaussian targets. This algorithm is further improved, and the possibility of probing high-dimensional targets is enabled, via GPU-accelerated numerical libraries and periodically synchronized concurrent chains (justified a posteriori). Asymptoti- cally in dimension, this massively parallel dimension-independent adaptive Metropolis (MPDIAM) GPU implementation exhibits a factor of four improvement versus the CPU-based Intel MKL version alone, which is itself already a factor of three improve- ment versus the serial version. The scaling to multiple CPUs and GPUs exhibits a form of strong scaling in terms of the time necessary to reach a certain convergence criterion, through a combination of longer time per sample batch (weak scaling) and yet fewer necessary samples to convergence. This is illustrated by e ciently sampling from several Gaussian and non-Gaussian targets for dimension d 1000.

Les précipitations résultent d'un phénomène atmosphérique caractérisé par une variabilité spatiale et temporelle forte. Cette variabilité dans la distribution des pluies et des évènements intenses a des impacts en hydrologie de surface (e.g. inondations) variés selon les régions du monde. Toute modification du climat tropical est associée à une modification du cycle de l'eau et de l'énergie dans ces régions. Dans un contexte de changement climatique, il est donc important de développer des outils permettant d'estimer quantitativement les précipitations, à l'échelle du globe, à la fois sur les surfaces continentales et les surfaces océaniques. Les travaux présentés dans cette thèse s'intéressent à l'observation des précipitations depuis l'espace. En effet, la mesure des pluies nécessite une densité d'observations élevée qui, sur l'ensemble des Tropiques, n'est accessible qu'à partir d'observations spatiales. Depuis plusieurs décades, les moyens satellitaires à disposition ont beaucoup évolué et offrent aujourd'hui une densité d'observations de plus en plus fortes. Grâce aux nouvelles missions déployées telles que Megha-Tropiques au sein de la future constellation GPM (Global Precipitation Measurement), on a accès à un ensemble de systèmes d'observations qui amène à une densité accrue d'observations spatiales. L'estimation quantitative des précipitations n'était possible qu'à l'échelle mensuelle, il est maintenant envisageable d'estimer la pluie par satellite à des échelles de temps de plus en plus fines. Cette thèse s'intéresse aux échelles 1°/1-jour, échelle clé pour les études météorologiques et hydrologiques. Il existe un large spectre de méthodes d'estimations de précipitations par satellite, de qualité inégale. Dans un premier temps, une analyse des produits issus des développements les plus récents montre que leur qualité a atteint un degré suffisant pour être utilisé de manière quantitative aux échelles de temps pertinentes en météorologie. Il apparaît également qu'à ces échelles de temps, il est nécessaire d'utiliser les estimations de cumul de précipitations conjointement avec leurs barres d'erreurs. Une nouvelle méthode d'estimations de précipitations sur l'ensemble de la ceinture tropicale, appelé TAPEER (Tropical Amount of Precipitation with an Estimate of ERrors), est donc développée dans le but d'estimer des cumuls de pluie et leurs erreurs associées à l'échelle 1°/1-jour. Cette approche est fondée sur une méthode de fusion de données de l'imagerie Infrarouge d'une constellation de satellites géostationnaires et d'estimations de taux de pluie issues de radiomètres Micro-ondes d'une constellation de satellites défilant. Des techniques modélisations sont mises en oeuvre afin d'associer une erreur aux cumuls de pluie produits. Une investigation détaillée du bilan d'erreur de la méthode TAPEER montre que les sources principales d'incertitudes sont liées à l'échantillonnage et aux biais systématiques sur les taux de pluie d'intensité moyenne. Une étude sur l'été 2009 révèle l'importance de l'utilisation de la barre d'erreur dans l'analyse de la distribution des pluies, en particulier pour les plus forts cumuls sur la ceinture tropicale

In February of 2014 NASA has launched the core observatory of The Global Precipitation Measurement Mission (GPM). Since then, the mission has been providing a wealth of observation data collected by the core observatory along with other satellites belonging to the mission space constellation. One of the most important data products that GPM provides is the Level 4 (L4) rainfall data product called Integrated Multi-satellitE Retrievals for GPM (IMERG). IMERG is constructed using the raw data collected by the Microwave (MW) sensors on board the constellation satellites along with the Infrared (IR) sensors on board geostationary satellites and the advance Dual-frequency Precipitation Radar (DPR) on board the GPM core satellite. The IMERG product is available globally for all interested researchers to use. In this dissertation, I focus on the applicability of IMERG in hydrologic applications, and specifically in flood peak modeling. In order to conduct a comprehensive evaluation of IMERG that is oriented towards hydrologic modeling. I have explored multiple hydrologic models which can be used to produce stream flow estimates using IMERG without the need of parameter calibration based on the model’s inputs. The calibration free capability is essential since model parameter calibration obscures the effect of the errors associated with the rainfall input on the estimated discharges, which in turn will limit our understanding about the distribution of the errors in IMERG over space and time. The two hydrologic models we used in this study are both physically based distributed models and were setup over the domain of the state of Iowa which is located in the United States’ Midwest. I also explored the performance of one of the hydrologic models’ component, which is the runoff-routing component, in order to estimate an additional portion of the errors in the discharge estimates that is not attributed to the model’s input but rather to the hydrologic model itself. A significant portion of my dissertation is concerned with identifying and using accurate methods to evaluate both IMERG and the hydrologic models’ outputs in a hydrologic context that is useful for flood modeling. Several studies have evaluated other satellite rainfall products using methods that vary in complexity. Some studies used the simplest methods of evaluation, such as, mean aerial differences and standard deviation of the differences (additive or multiplicative) compared to a benchmark rainfall product. This is done without taking the spatial dependency of the errors in space into consideration. Other studies modeled the spatial dependency (correlation) between the errors in the rainfall product, however, using Euclidean distance based approaches that do not account for the hydrologic basins’ shape and size. Nevertheless, it is important to realize that hydrologic models will eventually aggregate the rainfall values, along with the errors associated with them, through a stream network that is dichotomous in nature and does not comply with Euclidean distance. Thus, we employed a stream based evaluation framework, called the Spatial Stream Network (SSN) approaches, to characterize the errors in IMERG taking into account the stream distances and the stream connectivity information between evaluation sites. Although previously used in applications such as modeling water temperatures and pollutant transport, to the best of my knowledge this approach has not been used in rainfall product evaluation before this study. The SSN analysis of IMERG allowed me to answer the question, “What is the proper basin scale which is capable of filtering out the correlated errors in IMERG by accumulating the rainfall values through the stream network?” Finally, in order to add value to the current methods of evaluating model simulated stream flows. I proposed a time based evaluation that is capable of detecting peaks in both the observed and simulated flows and estimating the lag time of the simulated peaks. Typically, previous studies have used simple skill scores such as Root Mean Squared Errors (RMSE), correlation coefficient, and Nash-Sutcliff Efficiency (NSE) to evaluate hydrograph performance as a whole, or the difference in time to peak which involves primitive peak detection method (e.g., a moving or a defined time window). In this dissertation I propose a Continuous Wavelet Transform (CWT) based method to evaluate the peak times and shapes produced by the hydrologic model. The method is based on filtering the frequencies in the hydrograph by treating it as a signal and detecting sharp features in both the observed and time series and the phase difference between them. We also emphasized on the importance of the choice of wavelet shape used in the evaluation, and how different wavelet shapes can affect the inference about the time series.