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We consider the Higgs branch of 5d fixed points engineered using brane webs with an O7$^+$-plane. We use the brane construction to propose a set of rules to extract the corresponding magnetic quivers. Such magnetic quivers are generically framed non-simply-laced quivers containing unitary as well as special unitary gauge nodes. We compute the Coulomb branch Hilbert series of the proposed magnetic quivers. In some specific cases, an alternative magnetic quiver can be obtained either using an ordinary brane web or a brane web with an O5-plane. In these cases, we find a match at the level of the Hilbert series., 21 pages

Quantum field theory (QFT), is a powerful framework to study diverse phenomena in physics. The range of topics includes the interactions of elementary particles, the continuum limit of condensed matter systems defined on a lattice, models of the expanding universe, as well as quantum gravity. Despite its enormous breadth of applications, it is still quite poorly understood. From a pragmatic point of view, a generic QFT is well understood in the per-turbative regime, where one has a small expansion parameter or coupling constant. That we have a satisfactory understanding of QFTs in the weakly coupled regime, is highlighted by the fact that we have a single formalism, namely feynman diagrams, that can be applied to any weakly coupled theory. Conversely, there is no universal framework to understand non-perturbative and strong coupling phenomena. Instead, we have a distinct set of tools, which apply to distinct sets of very special theories, such as those with supersymmetry or topolog-ical theories. From this perspective, to understand the strong coupling dynamics of a QFT, is to develop a unique formalism that can be applied to solve a generic strongly coupled QFT. The reader should be warned that this thesis will not achieve such an ambitious goal. How-ever, it is good to keep this general philosophy in mind, as a broader motivation for some of the work presented. We will provide, instead, a collection of data points for particular sec-tors of strongly coupled QFTs that are under analytic control. One can hope that some day, these data points can provide the foundations for a more systematic and universal approach. From a more formal viewpoint, quantum field theory, as of yet, has no rigorous mathemati-cal basis. This is particularly bothersome, given the deep interconnections between ideas in modern mathematics and those of QFT [1]. The goal of this thesis is to introduce its reader to a few notable examples, where the former issue can be overcome. The unifying theme of all these examples is their relation to brane dynamics in string theory [2]. We will make extensive use of the string theory embedding of the QFTs under consideration, in order to illuminate their strong coupling dynamics.

We study the moduli space of 3d $\mathcal{N}=4$ quiver gauge theories with unitary, orthogonal and symplectic gauge nodes, that fall into exceptional sequences. We find that both the Higgs and Coulomb branches of the moduli space factorise into decoupled sectors. Each decoupled sector is described by a single quiver gauge theory with only unitary gauge nodes. The orthosymplectic quivers serve as magnetic quivers for 5d $\mathcal{N}=1$ superconformal field theories which can be engineered in type IIB string theories both with and without an O5 plane. We use this point of view to postulate the dual pairs of unitary and orthosymplectic quivers by deriving them as magnetic quivers of the 5d theory. We use this correspondence to conjecture exact highest weight generating functions for the Coulomb branch Hilbert series of the orthosymplectic quivers, and provide tests of these results by directly computing the Hilbert series for the orthosymplectic quivers in a series expansion., Comment: 46 pages, 10 tables, many pictures, v2: references added, typos corrected, v3: Appendix E added, matches published version

We present the holographic dual for the strongly coupled, low energy dynamics of balanced ${\cal N}=4$ field theories in $(2+1)$ dimensions. The infinite family of Type IIB backgrounds with AdS$_4\times S^2\times S^2$ factors is described in terms of a Laplace problem with suitable boundary conditions. The system describes an array of D3, NS5 and D5 branes. We study various aspects of these Hanany--Witten set-ups (number of branes, linking numbers, dimension of the Higgs and Coulomb branches) and encode them in holographic calculations. A generic expression for the Free Energy/Holographic Central Charge is derived. These quantities are then calculated explicitly in various general examples. We also discuss how Mirror Symmetry is encoded in our Type IIB backgrounds. The connection with previous results in the bibliography is made., 25 pages plus appendices

draining the flood of enormous dams and transmitting the procedure to the downstream is one of the important issues regarding hydraulic structures. Plunge pools are the main structures to dissipate the high rate of energy. The amount of energy at an outlet jet depends on various parameters such as the dropping height, the thickness of the jet, and other environmental conditions. Local erosion in plunge pools with alluvial beds is a complex phenomenon and determining the geometric features of the scour hole is really difficult. The outlet flow mixes with the turbulence factor and hits the bed of the plunge pools with a semi-perpendicular condition. Therefore, the present study was conducted to determine the scour which was caused by inlet air along the middle water jet on the bottom of the plunge pools. Xu et al. (2004) tested the aeration effects on the scouring caused by the falling jet and obtained a small relationship between the percentage of air jet density and the relative scour depth. The results informed that aeration affects the shape of the scour hole and essentially reduces the scour depth. Manso et al. (2004) investigated the interaction of the geometric shape of the submerged pond with rocky bedding on the rate of diffusion of the falling jet. They tested various diameters of jets,5.5, 11 and 16.5 times the diameter of falling jet, on the smooth and rough beds to investigate the dynamic pressures with frequencies between 1 to 2 KHZ. Their findings showed that the geometric shape of the pond has a direct impact on the jet diffusion rate. Duarte et al. (2015) studied the effects of air inlet to jet on the dynamical pressure on the floor of the submerged pond. They increased the jet's velocity to 22 m/s. The final results showed that the air inlet to the jet led to a decline in the total pressure on the floor of the pond.

Developing of techniques for regional flood frequency estimation in ungauged sites is one of the foremost goals of contemporary hydrology. The flood frequency evaluation for ungauged catchments is usually approached by deriving suitable statistical relationships (models) between flood statistics and basins characteristics. Already, several equations have been presented to estimate the flood frequency in different areas such as Karkheh basin. However, due to the complexity of this phenomenon, the relationships have not been capable to simulate the flood frequency with desired accuracy. Accordingly, in this study, in addition to the regression method has been used in the previous studies, the ANN and ANFIS models are applied. In fact, these are a type of black box models without any knowledge of processes within the system, in which inputs are converted into outputs (or output). This situation indicates that this type of new models is actually similar to the regression relations, however, there is further flexibility in adjusting the weights and thus can be used as a replacement to multivariate regressions.

The scour process induced by plunging jets is an important topic for hydraulic engineers. It is important to forecast the various scour hole characteristics for avoiding the failure of a hydraulic structure. Base on this evidence, this study aimed to investigate the equilibrium morphology caused by vertical circular impinging jet. Aderibigbe andRajaratnam (1996) classified the flow patterns over asymptotic scour hole based on the values of the erosion parameter (Ec) and the pressure parameter (K) as either the strongly deflected Jet regime (SDJR) or the weakly deflected jet regime (WDJR). It appears that the two regimes are linked by a narrow transition regime. Chakravarti et al. (2013) conducted experiments to investigate the effect of static and dynamic scouring in plunge pool under submerged circular vertical jets. In this study, the process of changing the plunge pool bed form has been studied under vertical jet impinging upon non-cohesive sediment.

Since the withdrawal of the observation wells at the plains done for the point, it is necessary to calculate the average groundwater level and also generalization the estimated water level from collected point to the surface of plain. The aim of this study is an investigation on the application of combined geostatistics method with optimized artificial neural networks by genetic algorithm in interpolation of groundwater level over Dezful and Zeidoon plains located in the Khozestan province. The obtained results from Cokriging, Kriging and IDW methods indicated that Cokriging with the Gaussian variogram and cross-variogram in Dezful Plain, and Kriging with the Gaussian variogram in Zeidoon plain are the best geostatistical methods for estimation the groundwater level and combined with artificial neural networks. Also the results of combination these two models showed that optimized model by genetic algorithm have better evaluation criteria than geostatistical methods and proposed as an effective combined model for estimation of the groundwater level. So that an application of this optimized combined method in Zeidoon plain with fewer observation wells was better than Dezful plain

We propose an embedding of U(N c ) QCD3 with a Chern-Simons term in string theory. The UV gauge theory lives on the worldvolume of a Hanany-Witten brane configuration in type 0B string theory in the presence of Sagnotti’s O′3 orientifold. We use the brane configuration to propose a magnetic Seiberg dual. We identify various phases of the magnetic theory with conjectured phases of QCD3. In particular the symmetry breaking and bosonization phases are both associated with condensation of the dual squark field. We also discuss the abelian theory without Chern-Simons term and argue that flavour symmetry is not broken. Finally, we also predict novel type 0B string dynamics from QCD dynamics.

One of the most serious consequences of climate change is how it will affect droughts and water resources. This study aims at investigating the impact of climate change on droughts conditions in Dezfool-Andimesh Plain using the Standard Precipitation Index (SPI). To achieve this objective, output of four general circulation models (GCMs) under the A2 scenario were downscaled for two climate stations in the period of 2060-2084 compared to the baseline period (1985-2009). Regarding the dominant crop grown in the study area, a 6-month SPI for the baseline and future periods were estimated under the four GCM-scenarios. Results revealed that there is an increase in the duration of severe and mild droughts while there is a decrease in the duration of moderate droughts. This implies that droughts will be a concern in the future during the growing season (for the dominant crop) which should be considered in water resources management.

In the conventional methods of flood frequency analysis, the flood peak variable is just considered and assumed that this variable follows some specific parametric distribution function. This assumption would restrict us and lead us to the limited available information to evaluate the flood risk. It is well known that a flood event has three variables of flood peak, volume and duration which are random in nature and are mutually dependent. In this research, the concept of the Copula function is briefly introduced and then used to modeling the dependency structure of the flood variables of the Karun River at the Ahvaz hydrometric stationand then estimate their joint probability distribution. We use three well-known and appropriate copulas, including Ali–Mikhail–Haq, Cook–Johnson and Gumbel–Hougaard which belong to the Archimedean class of copulas, to modeling the joint probability distribution of the flood variables, where the marginal distributions of the flood’s variables are selected from the parametric and non-parametric distributions. The Gumbel–Hougaard family led to better modeling of different combination of flood’s variables based on goodness of fit criteria. The selected copula is used to estimate conditional cumulative distribution function and joint return periods which lead to better estimation of flood risk.

Human activities in the recent years have considerably increased the rate of water pollution in many regions of the world. In this case study, the main sources of wastewater discharging into the Gargar River were identified. Using river and point source flow rates and water quality parameters measured along the river, the river water quality was simulated using a commonly used, one-dimensional water quality model, the QUAL2K model. Simulated values of DO, CBOD, NH4-N and NO3-N demonstrated the accuracy of the model and despite a significant data shortage in the study area, QUAL2K model was found to be an acceptable tool for the assessment of water quality. Still, for this case study, it was found that the model was most sensitive to river and point source flows and moderate to fast CBOD oxidation, and nitrification rates.

One of the most important information which is effective in desirable utilization of water resources is the information related to predicting the future available water in the catchment. Considering the existing uncertainty it is of significant importance when streamflow forecasting information is used. The ensemble stream flow prediction (ESP) is one of the methods in considering the forecast uncertainty. The goal of this research is to develop and evaluate monthly ESP for Roud Zard basin in Iran. Two models have been used to produce ESP: A conceptual river flow model based on Tank method (CRFM), and Combining the CRFM model with the adaptive neuro fuzzy inference system (ANFIS) to develop a hybrid model. Following, the Event bias correction method is employed on generated ESP’s and the results of the three predictions have been evaluated. The results show that the precision of base stream flow simulation model had considerable effects in the quality of the ensemble prediction as far as RPS in hybrid model that had higher precision than CRFM model has decreased from 0.56 to 0.38 and the months with suitable prediction (positive skills score) increased from 82 to 115 months and in case of employing bias correction, there will be an increase to 119 months from the total 182 months of simulation period.