Restoration of an active MV distribution grid with a battery ESS: A real case study

In order to improve power system operation, Battery Energy Storage Systems (BESSs) have been installed in high voltage/medium voltage stations by Distribution System Operators (DSOs) around the world. Support for restoration of MV distribution networks after a blackout or HV interruption is among the possible new functionalities of BESSs. With the aim to improve quality of service, the present paper investigates whether a BESS, installed in the HV/MV substation, can improve the restoration process indicators of a distribution grid. As a case study, an actual active distribution network of e-distribuzione, the main Italian DSO, has been explored. The existing network is located in central Italy. It supplies two municipalities of approximately 10,000 inhabitants and includes renewable generation plants. Several configurations are considered, based on: the state of the grid at blackout time; the BESS state of charge; and the involvement of Dispersed Generation (DG) in the restoration process. Three restoration plans (RPs) have been defined, involving the BESS alone, or in coordination with DG. A MATLAB®/Simulink® program has been designed to simulate the restoration process in each configuration and restoration plan. The results show that the BESS improves restoration process quality indicators in different simulated configurations, allowing the operation in controlled island mode of parts of distribution grids, during interruptions or blackout conditions. The defined restoration plans set the priority and the sequence of controlled island operations of parts of the grid to ensure a safe and better restoration. In conclusion, the results demonstrate that a BESS can be a valuable element towards an improved restoration procedure

Morphological and morphometric analysis of Nekemias arborea and Ampelopsis aconitifolia (Vitaceae)

Leaf morphology in angiosperms is not constrained by the leaf’s important function of providing energy through photosynthetic reactions. In just one family, Vitaceae, it is easy to observe among it’s over 900 species, various leaf shapes and sizes even among closely related species as well as within individual species. Observation of these leaf forms within species can be used to determine, for example where a vine transitions from the juvenile state to the adult state as well as their relationship to the spatial and temporal patterning of inflorescence initiation. Analysis of two species within the Ampelopsis clade, one that retained ancestral leaf characters, Nekemias arborea, was compared with a species containing derived leaf characters, Ampelopsis aconitifolia, so that leaf shape relationships between members of the grape family could be assessed. Knowledge about the members of the Ampelopsis clade can help to reveal a better understanding of the development of the very important commercial species, Vitis vinifera (grape). Leaf development along the vines of each species was tracked to draw comparisons and divergences in leaf shape. Structures along the vine, such as tendrils and axillary buds, were also noted to establish a vine pattern and to help determine whether a correlation exists between these traits and leaf shape changes. Scanning electron microscopy was used to observe leaf initiation and shape elaboration from the shoot apical meristem. Landmarks on mature leaves were established using vein and dissection patterns and were statistically analyzed. Morphometric analysis using Elliptic Fourier Descriptors (EFD) was performed to establish relationships in leaf form between two species of within Vitaceae

Regulation Of Axon Guidance Receptor Expression And Activity During Neuronal Morphogenesis

Receptors expressed on the surface of neurons during development direct cell migration, axon guidance, dendrite morphogenesis, and synapse formation by responding to cues in the neuron’s environment. The expression levels and the activity of cell surface receptors must be tightly controlled for a neuron to acquire its unique identity. Transcriptional mechanisms are essential in this process, and many studies have identified requirements for specific transcription factors during the different steps of neural circuit assembly. However, the downstream effectors by which most of these factors control morphology and connectivity remain unknown. In Chapter 1, I highlight recent work that elucidated functional relationships between transcription factors and the cellular effectors through which they regulate neural morphogenesis and synaptogenesis in multiple model systems. In Chapters 2 and 3, I present data demonstrating that the homeodomain transcription factors Hb9 and Islet control motor axon guidance in Drosophila embryos through distinct effectors: Hb9 regulates the (Roundabout) 2 receptor in a subset of motor neurons, while Islet acts in the same cells to regulate the Frazzled/DCC receptor. Genetic rescue experiments indicate that these relationships are functionally important for the guidance of motor axons to their muscle targets. In addition, Islet regulates motor neuron dendrite targeting in the central nervous system (CNS) through Frazzled, demonstrating how an individual transcription factor can control multiple aspects of neuronal connectivity through the same effector. In Chapter 4, I characterize a non-canonical function for the Robo2 receptor during midline crossing, and present data suggesting that this activity requires Robo2 to be expressed in midline cells, providing an example of how mechanisms that regulate guidance receptor gene expression are key to regulating receptor function and nervous system formation. In Chapter 5, I explore the implications of these findings, and propose future directions of research to build upon them

Development of a Computer Algorithm for Generation of Primers for Nucleic Acid Sequence Based Amplification (NASBA)

Nucleic acid sequence based amplification (NASBA) is a primer based isothermal method of RNA/DNA amplification. Currently, primer design for NASBA has been restricted to hand creating sequences of oligonucleotides that must follow a set of rules to be compatible for the amplification process. This process of hand-creating primers is prone to error and time intensive. The detection of mutants, post amplification, also offers a benefit in point of care scenarios and the design of hybridization probes for sequences in the region of amplification is also an erroneous and time intensive process. By creating a program to design primers and hybridization probes based on the set of rules provided for a sequence of user input DNA or RNA, one can avoid costly errors in primers design and save time. Utilizing Python (a high-level object-oriented programming language), along with a series of bioinformatic libraries such as Biopython and UNAfold one can definitively choose the best primer sequences for a given sample of DNA

Assessment of integrated solutions for the combined energy efficiency improvement and seismic strengthening of existing URM buildings

The European building stock is an aging infrastructure, mainly built prior to building codes. Furthermore, 65% of these buildings are located in seismic regions, which need to be both energetic and seismically retrofitted to comply with performance targets. Given this, this manuscript presents integrated constructive solutions that combine both energy efficiency improvement and seismic strengthening. The goal and novelty is to design and to evaluate one-shot, compatible, noninvasive, and complementary solutions applied to the façades of buildings with a minimum cost. To do so, different constraints have been borne in mind: the urban environment, achievable seismic and energy performance targets, and reduced construction costs. The method was applied to an old Spanish neighbourhood constructed in the 1960s. Different retrofitting packages were proposed for an unreinforced masonry case study building. A sensitivity analysis was performed to assess the effects of each configuration. A benefit/cost ratio was proposed to comparatively assess and to rank the solutions. The results of the seismoenergetic performance assessment showed that improving the behaviour of walls leads to higher benefit ratios than improving the openings. However, this latter strategy generates much lower construction costs. Integrating seismic into energetic retrofitting solutions supposes negligible additional costs but can improve the seismic behaviour of buildings by up to 240%. The optimal solution was the addition of higher ratios of steel grids and intermediate profiles in openings while adding thermal insulation in walls and renovating the window frames with PVC and standard 4/6/4 double glazing

Models and Solution Approaches for Efficient Design and Operation of Wireless Sensor Networks

Recent advancements in sensory devices are presenting various opportunities for widespread applications of wireless sensor networks (WSNs). The most distinguishing characteristic of a WSN is the fact that its sensors have nite and non-renewable energy resources. Many research e orts aim at developing energy e cient network topology and routing schemes for prolonging the network lifetime. However, we notice that, in the majority of the literature, topology control and routing problems are handled separately, thus overlooking the interrelationships among them. In this dissertation, we consider an integrated topology control and routing problem in WSNs which are unique type of data gathering networks characterized by limited energy resources at the sensor nodes distributed over the network. We suggest an underlying hierarchical topology and routing structure that aims to achieve the most prolonged network lifetime via e cient use of limited energy resources and addressing operational speci cities of WSNs such as communication-computation trade-o , data aggregation, and multi-hop data transfer for better energy e ciency. We develop and examine three di erent objectives and their associated mathematical models that de- ne alternative policies to be employed in each period of a deployment cycle for the purpose of maximizing the number of periods so that the network lifetime is prolonged. On the methodology side, we develop e ective solution approaches that are based on decomposition techniques, heuristics and parallel heuristic algorithms. Furthermore, we devise visualization tools to support our optimization e orts and demonstrate that visualization can be very helpful in solving larger and realistic problems with dynamic nature. This dissertation research provides novel analytical models and solution methodologies for important practical problems in WSNs. The solution algorithms developed herein will also contribute to the generalized mixed-discrete optimization problem, especially for the problems with similar characteristics

How efficiently can one untangle a double-twist? Waving is believing!

It has long been known to mathematicians and physicists that while a full rotation in three-dimensional Euclidean space causes tangling, two rotations can be untangled. Formally, an untangling is a based nullhomotopy of the double-twist loop in the special orthogonal group of rotations. We study a particularly simple, geometrically defined untangling procedure, leading to new conclusions regarding the minimum possible complexity of untanglings. We animate and analyze how our untangling operates on frames in 3-space, and teach readers in a video how to wave the nullhomotopy with their hands.Comment: To appear in The Mathematical Intelligencer. For supplemental videos, see http://www.math.iupui.edu/~dramras/double-tip.html , or https://www.youtube.com/playlist?list=PLAfnEXvHU52ldJaOye-8kZV_C1CjxGx2C . For a supplemental virtual reality experience, see http://meglab.wikidot.com/visualizatio

A Framework for the Design and Analysis of High-Performance Applications on FPGAs using Partial Reconfiguration

The field-programmable gate array (FPGA) is a dynamically reconfigurable digital logic chip used to implement custom hardware. The large densities of modern FPGAs and the capability of the on-thely reconfiguration has made the FPGA a viable alternative to fixed logic hardware chips such as the ASIC. In high-performance computing, FPGAs are used as co-processors to speed up computationally intensive processes or as autonomous systems that realize a complete hardware application. However, due to the limited capacity of FPGA logic resources, denser FPGAs must be purchased if more logic resources are required to realize all the functions of a complex application. Alternatively, partial reconfiguration (PR) can be used to swap, on demand, idle components of the application with active components. This research uses PR to swap components to improve the performance of the application given the limited logic resources available with smaller but economical FPGAs. The swap is called ”resource sharing PR”. In a pipelined design of multiple hardware modules (pipeline stages), resource sharing PR is a technique that uses PR to improve the performance of pipeline bottlenecks. This is done by reconfiguring other pipeline stages, typically those that are idle waiting for data from a bottleneck, into an additional parallel bottleneck module. The target pipeline of this research is a two-stage “slow-toast” pipeline where the flow of data traversing the pipeline transitions from a relatively slow, bottleneck stage to a fast stage. A two stage pipeline that combines FPGA-based hardware implementations of well-known Bioinformatics search algorithms, the X! Tandem algorithm and the Smith-Waterman algorithm, is implemented for this research; the implemented pipeline demonstrates that characteristics of these algorithm. The experimental results show that, in a database of unknown peptide spectra, when matching spectra with 388 peaks or greater, performing resource sharing PR to instantiate a parallel X! Tandem module is worth the cost for PR. In addition, from timings gathered during experiments, a general formula was derived for determining the value of performing PR upon a fast module