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Spatial information plays a critical role in remote sensing and mapping applications such as environment surveying and disaster monitoring. An Unmanned Aerial Vehicle (UAV)-borne mobile mapping system (MMS) can accomplish rapid spatial information acquisition under limited sky conditions with better mobility and flexibility than other means. This study proposes a long endurance Direct Geo-referencing (DG)-based fixed-wing UAV photogrammetric platform and two DG modules that each use different commercial Micro-Electro Mechanical Systems’ (MEMS) tactical grade Inertial Measurement Units (IMUs). Furthermore, this study develops a novel kinematic calibration method which includes lever arms, boresight angles and camera shutter delay to improve positioning accuracy. The new calibration method is then compared with the traditional calibration approach. The results show that the accuracy of the DG can be significantly improved by flying at a lower altitude using the new higher specification hardware. The new proposed method improves the accuracy of DG by about 20%. The preliminary results show that two-dimensional (2D) horizontal DG positioning accuracy is around 5.8 m at a flight height of 300 m using the newly designed tactical grade integrated Positioning and Orientation System (POS). The positioning accuracy in three-dimensions (3D) is less than 8 m.

In this paper is to performance and analysis of grid connected power flow control and power quality improvement in distribution generation (DG) system a new topology of harmonic injection current, connected for a grid mode and DC motor drive. Inherently the system power factor is low and it has high harmonic content in the current. The Swiss rectifier is based on harmonic current injection methods on power flow control and implementation of Power factor correction (PFC), Rectifier, the harmonic mitigating pulse width modulation (PWM) technique have been used to reduce the harmonics for power quality improvement. The renewable sources have been used as DC source and control technique has been used with step up DC-DC converter to regulate DC-link voltage. The second close loop control has been done for voltage source inverter to stabilize its terminal voltage. The DC-AC converter provides the bidirectional power flow between point of common coupling (PCC) and local load. The step up converter regulates the DC link voltage to exchange the power with the three phase feeders, also it is conformed the harmonic current can be satisfied with the proposed method. The simulation Study is performed in MATLAB/ SIMULINK. [ABSTRACT FROM AUTHOR]

In this paper, an optimum recloser and fuse coordination scheme is proposed in the presence of multiple distributed generators (DGs) in a radial distribution network. The proposed approach formulates the recloser and fuse coordination problem as an optimisation problem and applies interior point method (IPM) to solve this optimisation problem for obtaining the optimum recloser and fuse settings. The proposed scheme gives a single set of the recloser and fuse settings which is robust enough to be able to coordinate the operations of the recloser and fuses properly without and in the presence of single/multiple DGs in the system. The effect of fault current limiter (FCL) on recloser–fuse coordination has also been studied. The proposed approach has been tested on IEEE 33‐bus system for three different scenarios: (i) no DG in the system, (ii) a single DG in the system, and (iii) multiple DGs in the system. Further, the optimum results obtained by IPM have been validated by comparing them with those obtained by modular in‐core non‐linear optimisation system solver, sequential quadratic programming, particle swarm optimisation, harmony search, genetic algorithm, and differential evolution techniques. The test results prove the robustness and effectiveness of the presented scheme. [ABSTRACT FROM AUTHOR]

A coordinated look‐ahead reactive power optimisation method is proposed to minimise the required number of operating control devices for a time horizon of 24 h. The aim is to determine, via solving a mixed integer non‐linear programming (MINLP) problem, optimum value settings of transformer taps, capacitor banks and reactive power output of distributed generators (DGs) based on the day‐ahead load demand and active power output of DGs satisfying the engineering and operational constraints. The proposed method employs a three‐stage method: assessment stage, time‐period‐partitioning stage, and coordinated reactive power optimisation stage. The first stage assesses the hourly voltage profile and available delivery capability margin of the system, while the time‐period‐partitioning stage uses clustering algorithm based on power‐flow solution to partition time periods into coherent time durations. The MINLP problem is solved in the proposed coordinated optimisation stage. A modified IEEE13 case and IEEE123 case are used to verify the effectiveness of the proposed three‐stage method. [ABSTRACT FROM AUTHOR]

Keeping voltage quality in isolated microgrids while feeding non‐linear and/or unbalanced loads is one of the major challenges in the control of these networks. This study proposes a new hierarchical control for enhancing voltage quality in sensitive load bus (SLB) of isolated microgrids considering non‐SLBs (NSLBs (DG buses and local buses)) with voltage quality limitations. At the primary level of this hierarchical control, a droop controller is responsible for controlling voltage and frequency of microgrids. The duty of the secondary control level is that in the case of the reduction of voltage quality indices at SLB, it enhances them to their determined levels by sending proper control signals to the primary level to determine each DGs compensation effort. It is worth noting that improving the voltage quality indices at SLB can lead to a drop in NSLBs voltage quality indices. Although NSLBs do not have the strict voltage quality limitation of SLB, but keeping the voltage quality of these buses in their allowed limitation is necessary. The third level of the proposed hierarchical control is designed to guarantee the voltage quality indices limitation at NSLBs. Simulation results are given to demonstrate the effectiveness of the proposed control scheme. [ABSTRACT FROM AUTHOR]

Multi‐functional grid‐connected inverter (MFGCI) is an effective solution for smart grid application to interface renewable energy sources and provide ancillary services. In this study, the controller of an MFGCI‐based distributed generator (DG) is investigated. On the basis of impedance reconfiguration, multiple coupled ancillary services of a DG are modelled to upgrade DG, including power quality conditioning, virtual synchronous generator emulation, and harmonic resonance damping. Analyses highlight potential benefits of DGs to actively participate in some possible services. From the perspective of impedance model, an upgrading solution is also proposed to coordinate these services in a DG. Using the proposed equivalent circuit model, these ancillary services can be uniformly considered as impedance control of the distribution network. Detailed models are presented to explain the principles of ancillary services. Experimental results of a test rig confirm the ancillary services of DG to enhance the power quality, provide virtual inertia, and eliminate the harmonic resonance. [ABSTRACT FROM AUTHOR]

In the case of emergency operation, intentional islanding of distributed generations is an interesting solution to maintain the reliable power supply in the smart distribution grid. This paper deals with an optimal systematic strategy to restore the post-contingency distribution grid after the occurrence of severe disturbances causing an outage. Hence, a two-stage solution procedure is developed in this paper. In the first step, the optimal partitioning scheme is addressed through a number of graph-theory related algorithms. By applying these algorithms, the loads are optimally assigned to the distributed generations and optimal load shedding programs are determined and performed if there is a shortage of generation. The second step deals with the adjustments issues. In fact, the preliminarily partitions achieved from the first stage should be checked for feasibility. Also, these partitions should be adjusted if it is necessary in order to satisfy the system related constraints. To this purpose OPF calculation is incorporated and optimal load management measures are taken to mitigate violations considering the voltage constraints, line capacities and controllable loads. Since the proposed method considers the key factors of load priorities, load controllability, power balance, voltage and line capacity constraints, it covers the requirements of practical applications. Numerical results from the PG&E-69 test system are used to verify the effectiveness of the proposed method. The comparison with previous methods demonstrates that the proposed method outperforms other techniques. [ABSTRACT FROM AUTHOR]

As there are different types of energy storage systems (ESS), it is important to have a tool that determines the best alternative to be installed in the distribution systems. This study presents a methodology for optimal determination of size, type and site of ESS in distribution systems with distributed generation (DG). The methodology uses a genetic algorithm and a power flow calculated by the Electric Power Research Institute software OPENDSS. For the optimal ESS charge and discharge management uses a non‐linear optimisation model that has as objective an energy cost and loss reduction. In addition, the methodology makes an energy management of the system by limiting the reverse flow with a load shifting process and a cost penalty. Solar and wind power are considered as DG modelled in Homer. Then, a genetic algorithm is used to select the size, type and site of the ESS, considering different lifecycles and costs. This methodology is tested in the IEEE 123 nodes system simulated and adapted in the OPENDSS and the formulation is implemented in MATLAB via COM interface. Finally, results of the methodology are presented and discussed. [ABSTRACT FROM AUTHOR]

Neuronal nitric oxide synthase (nNOS) 1 , mainly responsible for NO release in central nervous system (CNS) 2 , plays a significant role in multiple physiological functions. However, the function of nNOS + interneurons in fear learning has not been much explored. Here we focused on the medial ganglionic eminences (MGE) 3 -derived nNOS + interneurons in fear learning. To determine the origin of nNOS + interneurons, we cultured neurons in vitro from MGE, cortex, lateral ganglionic eminence (LGE) 4 , caudal ganglionic eminences (CGE) 5 and preoptic area (POA) 6 . The results showed that MGE contained the most abundant precursors of nNOS + interneurons. Moreover, donor cells from E12.5 embryos demonstrated the highest positive rate of nNOS + interneurons compared with other embryonic periods (E11.5, E12, E13, E13.5 and E14). Additionally, these cells from E12.5 embryos showed long axonal and abundant dendritic arbors after 10 days culture, indicating the capability to disperse and integrate in host neural circuits after transplantation. To investigate the role of MGE-derived nNOS + interneurons in fear learning, donor MGE cells were transplanted into dentate gyrus (DG) 7 of nNOS knock-out (nNOS −/− ) or wild-type mice. Results showed that the transplantation of MGE cells promoted the acquisition of nNOS −/− but not the wild-type mice, suggesting the importance of nNOS + neurons in fear acquisition. Moreover, we transplanted MGE cells from nNOS −/− mice or wild-type mice into DG of the nNOS −/- mice and found that only MGE cells from wild-type mice but not the nNOS −/− mice rescued the deficit in acquisition of the nNOS −/− mice, further confirming the positive role of nNOS + neurons in fear learning. [ABSTRACT FROM AUTHOR]

Distributed generation (DG) is increasingly being integrated into distribution networks, and the coordinated allocation of controllable devices including capacitor banks and SOPs is an important issue. This paper proposes a coordinated optimal allocation method of DGs, capacitor banks and SOPs in active distribution network. Firstly, the multistate models of renewable energies and loads considering time-sequence are developed, in order to obtain the operation scenarios of the power grid and probability in different periods. Then, a bi-level programming model is established, in which a chance-constrained programming is embedded. The sitting and sizing of DGs, capacitor banks and SOPs are optimized in upper level considering minimum annual cost as objective. Chance constraint programming is embedded in upper and lower level to obtain the optimal results under a confident level because of the uncertain outputs of DGs. Simulations studies are performed to verify the proposed method. [ABSTRACT FROM AUTHOR]

We develop and analyze a new hybridizable discontinuous Galerkin method for solving third-order Korteweg-de Vries type equations. The approximate solutions are defined by a discrete version of a characterization of the exact solution in terms of the solutions to local problems on each element which are patched together through transmission conditions on element interfaces. We prove that the semi-discrete scheme is stable with proper choices of stabilization function in the numerical traces. For the linearized equation, we carry out error analysis and show that the approximations to the exact solution and its derivatives have optimal convergence rates. In numerical experiments, we use an implicit scheme for time discretization and the Newton-Raphson method for solving systems of nonlinear equations, and observe optimal convergence rates for both the linear and the nonlinear third-order equations. [ABSTRACT FROM AUTHOR]

Granule cells in the dentate gyrus regenerate constantly in adult hippocampus and then integrate into neural circuits in the hippocampus thereby providing the neural basis for learning and memory. Promoting the neurogenesis in the hippocampus facilitates learning and memory such as spatial learning, object identification, and extinction learning. The interaction between neuronal nitric oxide synthase (nNOS) and postsynaptic density protein-95 (PSD-95) is reported to negatively regulate neurogenesis in brain, so we hypothesized that disrupting this interaction might facilitate the neurogenesis in the dentate gyrus (DG) and thus enhance the extinction memory retrieval of fear learning. We found that uncoupling the nNOS-PSD-95 complex in remote contextual fear condition promoted both neuronal proliferation and survival in the DG, contributing to an enhanced retrieval of the extinction memory. Moreover, the nNOS-PSD-95 uncoupling-induced neurogenesis may be mediated by the extracellular signal-regulated kinase (ERK) as the phosphorylation level of ERK1/2 was increased after uncoupling. These findings suggest that the nNOS-PSD-95 complex may serve as a novel target for the treatment of post-traumatic stress disorder (PTSD). [ABSTRACT FROM AUTHOR]

Provable stable arbitrary order symmetric interior penalty (SIP) discontinuous Galerkin discretizations of heterogeneous, incompressible Stokes flow utilizing Qk²-Qk--1 elements and hierarchical Legendre basis polynomials are developed and investigated. For solving the resulting linear system, a block preconditioned iterative method is proposed. The nested viscous problem is solved by a hp-multilevel preconditioned Krylov subspace method. For the p-coarsening, a two-level method utilizing element-block Jacobi preconditioned iterations as a smoother is employed. Piecewise bilinear (Q12) and piecewise constant (Q0²) p-coarse spaces are considered. Finally, Galerkin h-coarsening is proposed and investigated for the two p-coarse spaces considered. Through a number of numerical experiments, we demonstrate that utilizing the Q1² coarse space results in the most robust hp-multigrid method for heterogeneous Stokes flow. Using this Q1² coarse space we observe that the convergence of the overall Stokes solver appears to be robust with respect to the jump in the viscosity and only mildly depending on the polynomial order k. It is demonstrated and supported by theoretical results that the convergence of the SIP discretizations and the iterative methods rely on a sharp choice of the penalty parameter based on local values of the viscosity. [ABSTRACT FROM AUTHOR]

Distributed generations (DGs) in the distribution systems are connected into the buses using power electronic converters. During fault, it is challenging to provide a constant impedance model for DGs in the system frequency due to the variable converter control strategies. System frequency impedance measurement based fault locations can be influenced by the converters' fault behaviour. This study addresses this problem by proposing a wide‐area high‐frequency impedance comparison based fault location technique. The high‐frequency impedance model of DG is provided. Based on the constant DG impedance model in high‐frequency range, the faulted line sections can be distinguished by comparing the measured impedance differences without requiring the exact distribution system parameters. Simulation results show that the proposed wide‐area transient measurements based fault location method can provide accurate faulted sections in the distribution systems with DGs regardless of the load and DG output variations, measurement noise, unbalanced loads and islanding operations. [ABSTRACT FROM AUTHOR]

In Isogeometric Analysis (IGA), the Discontinuous Galerkin method (IGA DG) is often applied when the domain is composed of multiple Non-Uniform Rational B-splines (NURBS) patches. These patches are often required to be C 0 -continuous to make the IGA DG available, and this requirement brings some problems to the CAD process. This paper extends the IGA DG method to solve problems on the union of the overlapped patches. With this method (IGAODG), a problem on the overlapped domain is seen as multiple sub-problems on the non-trimmed patches, and then the continuities of traces of the numerical solutions are penalized on the boundaries of non-trimmed elements, with the coefficients deduced from the classical DG method. Comparing with the IGA methods which apply the CAD Boolean operations to deal with the overlapped domains, the presented method carries out the integrations in the non-trimmed patches, thus no additional integration scheme needs to be considered to achieve the Gaussian integration precision. Discussions on the presented discretization scheme and its convergence analysis show that this method is available on the domain created by the union of the matched, mismatched and overlapped patches. As predicted in the convergence analysis, the presented method gives the optimal convergence rates in our numerical examples. Finally, through one of its engineering applications, this paper shows how to extend IGAODG to solve problems that are defined on the trimmed patches. [ABSTRACT FROM AUTHOR]

In our study expression of phospho-(Ser-10)-histone H3 (pH3S10), a marker for the early stage of neurogenesis, and cellular early response genes were investigated using c-Fos protein as an example of a transcription factor in the neurogenic process in rats. Neurogenesis in the adult brain is regulated by endo- and exogenous factors, which influence the proliferation potential of progenitor cells and accelerate the dendritic development of newborn neurons. D-amphetamine, a psychoactive substance, is one of the exogenous factors able to influence the process of neurogenesis. The rats were injected with D-amphetamine at a dose of 1.5 mg/kg/body weight (b.w.) under one administration scheme. Analysis of the pH3S10 and c-Fos expression levels in the group of D-amphetamine administered rats provided evidence of enhanced expression of these proteins in the regions of neurogenesis occurrence in rats. However, conclusions concerning stimulant effects of amphetamine on neurogenesis should be formulated with great caution, taking into account amphetamine dosage and the administration scheme. It should also be remembered that doses of psychoactive substances used in animal models can be lethal to humans. [ABSTRACT FROM AUTHOR]

Development of Distributed generations (DGs) has changed the nature of power networks from passive to active. In order to specify a proper model for DG units, function and connection style of DGs to the network (direct or indirect) must be clarified. In this paper, operation of DGs in an unbalanced condition (due to unbalanced loads) will be studied. A three-phase power flow model is used to confirm the certainty of the proposed model. Generally DG modelling, depend on its type and controlling circuit, is like either PV or PQ bus. In this paper a three-phase unbalanced power flow model using Newton-Raphson method over a 4 buses power system is implemented. Based on the type of bus (PV or PQ), Simulation results show that the DGs can improve voltage profile (NEME and IEEE unbalance factor) and reduce network losses.

The world has witnessed a rapid transformation in the field of electrical generation, transmission and distribution. We have been constantly developing and upgrading our technology to make the system more economically efficient. Currently, the industry faces an acute shortage of energy resources due to overconsumption by industries worldwide. This has compelled experts to look for alternatives to fossil fuels and other conventional sources of energy to produce energy in a more sustainable manner. The microgrid concept has gained popularity over the years and has become a common sight all over the world because of the ability of a microgrid to provide power to a localized section without being dependent on conventional resources. This paper focuses on development of such an AC hybrid microgrid, which receives power from distributed energy resources (DERs) such as a PV array alongside a battery storage system, and also uses an emergency diesel generator system and an online uninterruptible power supply (UPS) system to provide power to predefined loads under different conditions. This paper also addresses on the power flow to the loads under two main modes of operation—on grid and off grid—and investigates the microgrid in different states and sub-states. The final objective is to design an efficient microgrid model such that it can sustain the multiple loads simultaneously under all operating conditions.