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1. Improving Power Distribution System Situational Awareness Using Visual Analytics

   https://doi.org/10.1109/SECON.2018.8479204  

   Lawanson, Tumininu; Karandeh, Roozbeh; Cecchi, Valentina; Wartell, Zachary; Cho, Isaac (April 2018, IEEE SoutheastCon 2018)

   Traditionally, distribution system operators had limited visibility beyond distribution system substations. It was not unusual for electric utilities to have insufficient information about the network and phase connectivity model for the distribution system. This resulted in limited situational awareness at the distribution system level. In this paper, a visual analytics approach to gleaning intelligence from the vast amounts of data accumulated in the distribution system is proposed. The web-based visual analytics interface integrates data from heterogeneous datasets such as AMI, GIS and SCADA. The interface is designed to enable distribution system operators visualize and analyze the state of the distribution system over time. This paper presents the use of the visual analytics system to identify mismatched meter-to-transformer associations and to visualize voltage violations in a real-world distribution network. 

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2. Power Dispatch Estimation from Electric Vehicles in a Distribution System

   https://doi.org/10.1109/EPECS62845.2024.10805530  

   Venayagamoorthy, Ganesh K; Subasinghe, Imanthi Kalanika; Naidoo, Raj (November 2024, IEEE)

   The integration of electric vehicles (EVs) into the electric power distribution system poses numerous challenges and opportunities for optimizing energy management and system operations. Electric vehicle grid interfaces (EVGIs), essentially bidirectional power converters, allow for charging/grid-to-vehicle (G2V) and discharging/vehicle-to-grid (V2G) power transfers. A power dispatch estimation (PDE) model for V2G, based on availability of EVs in a distribution system and capabilities of the distribution system, is needed to assist in grid operations. This paper presents the development of a PDE model based on nodal power flows to capture the complex spatiotemporal dependencies inherent in G2V and V2G patterns. The hierarchical structure of a distribution system, feeder to EVGI node, is taken into consideration for PDE. Typical PDE estimation results are presented for the IEEE 34 test node feeder distribution system allocated with EVGIs. 

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3. Control of a Noncooperative Positive Nonlinear System by Augmented Positive Linear System Regulation

   https://doi.org/10.1109/LCSYS.2024.3522944  

   Liu, Guanyun; Menezes, Amor A (December 2024, IEEE Control Systems Letters)

   Positive systems, which are systems whose states are always non-negative, can have both positive linear and positive nonlinear approximations that are valid dynamical models in a prescribed domain. When a linearization of a nonlinear system in a domain near an operating point is equivalent to another linear system representation, a reference-tracking controller for that linear system should also achieve reference-tracking control of the nonlinear system in that domain. Here, we show that only if a linearized positive nonlinear system (PNS) is a positive system (i.e., the PNS is cooperative) will a reference-tracking controller for an equivalent positive linear system realization achieve similar results on the nonlinear system. For an example noncooperative PNS of human blood coagulation, where a published reference-tracking controller assumed a positive linear plant, we develop feedforward and feedback controllers that augment the prior controller to overcome noncooperativity and similarly control the positive nonlinear model. 

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4. Phrase-Verified Voting: Verifiable low-tech remote boardroom voting

   Blanchard, Enka; Robucci, Ryan; Selker, Ted; Sherman, Alan T. (January 2021, Cryptologia)

   null (Ed.)

   We present Phrase-Verified Voting, a voter-verifiable remote voting system easily assembled from commercial off-the-shelf software for small private elections. The system is transparent and enables each voter to verify that the tally includes their ballot selection without requiring any understanding of cryptography. This system is an example of making voter verification usable. The paper describes the system and an experience with it in fall 2020, to vote remotely in promotion committees in a university. Each voter fills out a form in the cloud with their selection $$V$$ for each race and a two-word passphrase $$P$$. The system generates a verification prompt of the $(V,P)$ pairs and a tally of the votes, organized to help visualize how the votes add up. After the polls close, each voter verifies that this table lists their $(V,P)$ pair and that the tally is computed correctly. The system is especially appropriate for any small group making sensitive decisions. Because the system would not prevent a coercer from demanding that their victim use a specified passphrase, it is not designed for applications where such malfeasance would be likely or go undetected. Results from 43 voters show that the system performed effectively for its intended purpose, and introduced users to the concept of voter-verified elections. Compared to the commonly-used alternatives of paper ballots or voting by email, voters found the system easier to use, and that it provided greater privacy and outcome integrity. 

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5. Assessment of lateral resolution of single random phase encoded lensless imaging systems

   https://doi.org/10.1364/OE.480591  

   Goswami, Saurabh; Wani, Pranav; Gupta, Gaurav; Javidi, Bahram (March 2023, Optics Express)

   In this paper, we have used the angular spectrum propagation method and numerical simulations of a single random phase encoding (SRPE) based lensless imaging system, with the goal of quantifying the spatial resolution of the system and assessing its dependence on the physical parameters of the system. Our compact SRPE imaging system consists of a laser diode that illuminates a sample placed on a microscope glass slide, a diffuser that spatially modulates the optical field transmitting through the input object, and an image sensor that captures the intensity of the modulated field. We have considered two-point source apertures as the input object and analyzed the propagated optical field captured by the image sensor. The captured output intensity patterns acquired at each lateral separation between the input point sources were analyzed using a correlation between the captured output pattern for the overlapping point-sources, and the captured output intensity for the separated point sources. The lateral resolution of the system was calculated by finding the lateral separation values of the point sources for which the correlation falls below a threshold value of 35% which is a value chosen in accordance with the Abbe diffraction limit of an equivalent lens-based system. A direct comparison between the SRPE lensless imaging system and an equivalent lens-based imaging system with similar system parameters shows that despite being lensless, the performance of the SRPE system does not suffer as compared to lens-based imaging systems in terms of lateral resolution. We have also investigated how this resolution is affected as the parameters of the lensless imaging system are varied. The results show that SRPE lensless imaging system shows robustness to object to diffuser-to-sensor distance, pixel size of the image sensor, and the number of pixels of the image sensor. To the best of our knowledge, this is the first work to investigate a lensless imaging system’s lateral resolution, robustness to multiple physical parameters of the system, and comparison to lens-based imaging systems. 

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