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Hourly Simulated Power Production Data with Snow Loss Model at Queued Utility-Scale PV Sites Simulated as Single-Axis Tracking Systems in the U.S. Eastern Interconnection for Weather Year 2021
No full textUsing 2021 weather data, we ran PySAM power production simulations for utility-scale PV sites in the U.S. Eastern Interconnection queue. Site IDs, capacities, and locations (counties) were extracted from Lawrence Berkeley National Laboratory’s Queued Up: 2024 Edition dataset. No panel mount information was provided, so all sites were assumed to be single-axis tracking systems. Sites’ latitudes and longitudes were assumed to be the centers of the installation counties. See queued_site_metadata.csv file for individual site metadata
Hourly Simulated Power Production Data with No Snow Loss Model at Queued Utility-Scale PV Sites Simulated as Single-Axis Tracking Systems in the U.S. Eastern Interconnection for Weather Year 2013
No full textUsing 2013 weather data, we ran PySAM power production simulations for utility-scale PV sites in the U.S. Eastern Interconnection queue. Site IDs, capacities, and locations (counties) were extracted from Lawrence Berkeley National Laboratory\u27s Queued Up: 2024 Edition dataset. No panel mount information was provided, so all sites were assumed to be the centers of the installation counties. See queued_site_metadata.csv file for individual site metadat
Incremental Planar Nearest Neighbor Queries with Optimal Query Time
No full textIn this paper we show that two-dimensional nearest neighbor queries can be answered in optimal O(log n) time while supporting insertions in O(log1+ϵ n) time. No previous data structure was known that supports O(log n)-time queries and polylog-time insertions. In order to achieve logarithmic queries our data structure uses a new technique related to fractional cascading that leverages the inherent geometry of this problem. Our method can be also used in other semi-dynamic scenarios
Hourly Simulated Power Production Data with Snow Loss Model at Existing Utility-Scale PV Sites (\u3e5 MW) in the U.S. Eastern Interconnection in 2014
No full textProject Summary: We ran PySAM power production simulations for utility-scale (\u3e5 MW) PV sites located in the U.S. Eastern Interconnection in the year 2014. Site panel mounts (fixed-tilt or single-axis tracking), capacities, and locations (latitudes and longitudes) were extracted from Lawrence Berkeley National Laboratory\u27s Utility-Scale Solar 2024 Edition dataset. See 2014_PV_existing_site_metadata.csv file for individual site metadata
Hourly Simulated Power Production Data with Snow Loss Model at Existing Utility-Scale PV Sites (\u3e5 MW) in the U.S. Eastern Interconnection in 2021
No full textProject Summary: We ran PySAM power production simulations for utility-scale (\u3e5 MW) PV sites located in the U.S. Eastern Interconnection in the year 2021. Site panel mounts (fixed-tilt or single-axis tracking), capacities, and locations (latitudes and longitudes) were extracted from Lawrence Berkeley National Laboratory\u27s Utility-Scale Solar 2024 Edition dataset. See 2021_PV_existing_site_metadata.csv file for individual site metadata
Ways researchers can use teacher noticing to inform the conceptualization of a complex teaching practice
No full textPrior research has examined teachers’ noticing in order to understand what factors affect teacher noticing and how mathematics teacher educators can support that noticing. We contend, however, that analyzing teachers’ noticing has the potential to be used for additional purposes. In this paper, we illustrate how we used teachers’ noticing as one tool for gaining insight into our conceptualization of a complex teaching practice—the practice of building on student mathematical thinking. We provide examples of how our analysis of instances of noticing enhanced our understanding of the practice of building by revealing aspects of the practice that we had never considered or were still underdeveloped. We also illustrate how instances of teacher noticing allowed us to gain insights into our own efforts to develop teachers’ understanding of the building practice, including areas where we thought we had been explicit but there was still evidence of incomplete understanding, areas where we needed to do something different or go deeper with the teachers, and areas where we had not been explicit about a critical aspect of the practice. The instances of noticing also revealed ways we needed to account for how important routines from the teachers’ own typical classroom teaching might interfere with aspects of building. Our findings illustrate how the study of teacher noticing can contribute to advancing researchers’ understanding not just of teachers’ noticing but also of the phenomena they are noticing
High inhibition efficiency and hydrogen permeation for novel N-heterocycles of SAE 1020 in HCl solution
No full textTo safeguard carbon steel during industrial acid pickling, it is essential to create corrosion and atomic hydrogen embrittlement inhibitors that are effective, non-toxic, and easily produced. Here, we synthesized and investigated the efficacy of 2-(nitromethylene)-1,3-oxazinane (NOX) and 2-(nitromethylene)hexahydropyrimidine (NHE) as corrosion inhibitors for SAE 1020 steel in 1.0 mol L−1 HCl aqueous solutions, within a concentration range of 3.7 mmol L−1 to 4.0 mmol L−1. For both inhibitors were obtained, an efficiency up to 82.7% (91.5%) for NHE (NOX), respectively. The NOX compound exhibited a 42.80% inhibitory efficacy of atomic hydrogen permeation. An anomalous behavior was noted in NOX, depending on its concentrations, leading to efficiency reduction. Theoretical calculations were performed using Density Functional Theory (DFT), where it was demonstrated that NOX is an energetically preferable molecule and has smaller binding energy compared with NHE. Two distinct concentrations of NOX molecules were examined, and at a higher concentration, an oxygen atom is released from the molecule and binds to the Fe surface. This phenomenon does not occur at low concentrations, and is ascribed to the anomalous behavior of the NOX molecule. Our finding paves the way for novel and high-efficiency N-heterocycle inhibitors
Case Study of Low-Volume Concrete and Thin Unbonded Concrete Overlay Projects in Michigan
No full textThe Michigan Department of Transportation (MDOT) undertakes demonstration projects to generate performance curves and determine the feasibility of adopting the construction method used in such projects as standard practice for MDOT projects. This paper focuses on analyzing pavement cost and performance data collected throughout the service life of two low-volume concrete pavements and two thin unbonded concrete overlay demonstration projects. The projects were assessed to verify if low-volume concrete pavement and thin unbonded concrete overlay could provide adequate performance and be accepted as a standard reconstruction method in Michigan. After about 13-18 years of service life, both methods have been found to provide acceptable performance at a reduced cost. Therefore, Low-volume concrete pavement and thin unbonded concrete overlay are recommended to be accepted as standard rehabilitation and reconstruction methods for MDOT
A longitudinal analysis of morphological shape variation of spleen in patients with fontan surgery
No full textBackground: Splenic size serves as a surrogate biomarker for predicting portal vein hyper-tension and liver abnormalities in subjects with Fontan Associated Liver Disease (FALD). We analyze the long-term shape variation of the spleen in FALD subjects using morphological shape features of radiomic features. Methods: We used 154 (84 from computed tomography and 70 from magnetic resonance) image volumes obtained from 36 individuals who underwent stage 3 Fontan procedure and 145 computed tomography images from controls to assess splenomegaly. To understand the splenomegaly, thirteen shape features of the spleen over three 10-year intervals, and variations between controls and FALD subjects were analyzed. Results: The spleen enlargement was observed in all intervals of the post-surgery period. Also, a significant difference (level of significance α = 0.05, p \u3c α) was observed between the morphological shape features of controls and the Fontan Associated Liver Disease subjects. Conclusion: Morphological shape features clearly distinguish between controls and subjects after Fontan stage 3 correction
Dichloroethene reduction by Fe(II): role of transient Fe(II) phases
No full textChlorinated ethenes (CEs) are some of the most commonly found groundwater contaminants, and their clean-up still relies heavily on energy intensive clean-up practices such as pump and treat. As a sustainable alternative, abiotic natural attenuation by Fe(II) species would be preferable. While data is available on reduction of some CEs by stable Fe(II) phases, these reactions appear to be slower than reduction by freshly precipitated, transient Fe(II) phases (i.e., reactive mineral intermediates, RMIs). Here, we evaluated cis-1,2-dichloroethene (cDCE) reduction by stable and transient Fe(II)-containing phases, and characterized the transient phases formed. In the absence of aqueous Fe(II) (Fe(II)), magnetite, chloride green rust, hematite, mackinawite, and clay minerals did not reduce cDCE. When Fe(II) was present with these minerals, reduction usually occurred when conditions favored precipitation of ferrous hydroxide (Fe(OH)). Additionally, we observed cDCE reduction by Fe(II) precipitates made from FeCl and ferrous ammonium sulfate (FAS), but never with FeSO present. Under no conditions, with or without Fe(II), was cDCE reduced by goethite, chukanovite, sulfate green rust, or aluminum oxide. Mössbauer spectra of the transient phases indicate that ferrous (oxy)hydroxides such as Fe(OH) formed from FeCl and FeSO and a green rust-like precipitate formed from FAS. These spectra suggest that reduction is faster when the phases are less ordered, possibly because the Fe(II) precipitates are less crystalline or form smaller particles. Our work suggests that although most stable Fe(II) phases do not reduce cDCE sufficiently fast for significant abiotic natural attenuation, Fe(II) RMI phases may contribute to attenuation of cDCE plumes