This research article thoroughly explores the electromagnetic behavior in silver metal at optical regime. Along the way, it uncovers some intriguing wave behaviors in terms of novel phenomenon – ...counterposition, negative phase velocity (NPV), orthogonal phase velocity (OPV) and/or negative refraction (NR), versus wavelength are investigated which is not previously deeply discussed in a silver configuration. Additionally, Minkowski momentum densities, revealing complex wave dynamics versus optical wavelength are studied first time for silver metal. Moreover, the influence on wave in silver metal due to L-nihility is notified fruitfully. These findings provide deeper insights platform for potential applications in diverse scientific and technological domains in condense matter physics, engineering and optics.
The need of undertaking effective actions against the climate change is pushing industrial companies to find new business models and technological solutions to reduce the resource utilization and the ...waste production. In this context, several companies are moving towards servitization, that has been proved as a promising strategy to enable sustainable business models in a wide spectrum, namely encompassing environmental, economic and social aspects. Nevertheless, companies lacks of tools for evaluating different servitization models with a clear view of economic and environmental benefits. This paper presents a model to estimate the profitability of servitization opportunities by combining economic Net Present Value index and environmental impacts estimation. The model is targeted on the steel sector, for which a preliminary application has been developed and is discussed in the paper. The results show that adopting different servitization business models, several benefits could be exploited both from providers and customers.
Quantifying non-photosynthetic vegetation (NPV) is important for ecosystem management and studies on climate change, ecology, and hydrology because it controls uptake of carbon, water, and nutrients ...together with frequency and intensity of natural fire, and serves as wildlife habitat. The ecological importance of NPV has driven considerable research on quantitatively estimating NPV in diverse ecosystems including croplands, forests, grasslands, savannah, and shrublands using remote sensing data. However, a comprehensive review is not available. This review highlights the theoretical bases and the critical elements of remote sensing for NPV estimation, and summarizes research on estimating fractional cover of NPV (NPV cover) and biomass using passive optical hyperspectral and multispectral remote sensing data, active synthetic aperture radar (SAR) and light detection and ranging (LiDAR), and integrated multi-sensorial data. We also discuss advantages and disadvantages of optical, LiDAR, and SAR data and pinpoint future direction on NPV estimation using remote sensing data. Currently, most NPV research has been mainly focused on NPV cover, not NPV biomass, using passive optical data, while a few studies have used LiDAR data to quantify NPV biomass in forests and SAR data on NPV estimation in croplands and grasslands. In the future, more efforts should be made to estimate NPV biomass and to investigate the best use of hyperspectral, LiDAR, SAR data, and their integration. The upcoming new optical sensor on Sentinel-2 satellites, Radarsat-2 constellation and NovaSAR, technological innovation in hyperspectral, LiDAR, and SAR, and improvements on methodology for information extraction and combining multi-sensorial data will provide more opportunities for NPV estimation.
In this paper we attempt to derive properties of the distribution of the net present value NPV, when the underlying cash flow is affected by stochastic disturbances in the form of a random walk ...process, the disturbances thus jumping continuously between each of two values. A leverage is introduced, affecting the size of each jump in relation to time.
A given time period is split into a number of sub-periods of equal length. During each sub-period, a fraction of altogether one monetary unit is transferred. This cash flow is subject to the random walk, and is discounted by a given constant discount rate. We study consequences on the distribution of the net present value as the number of sub-periods increases beyond all bounds.
Two different processes are studied, which turn out to have rather different properties. In the first, Case A, the two levels between each jump, are chosen as each other's negative, and in the second, Case B, except for a timing factor, as each other's inverse. Among other consequences, it is shown that the probability distribution of the NPV in Case A is close to, but different from, a lognormal distribution, and that in Case B, the NPV indeed has a lognormal distribution, but lies stable at a constant value. Also is shown that in Case A, the leverage must be at least 1/2 for a limiting distribution to exist, and in Case B at least unity. For leverage values above these values, respectively, the random walk will not affect NPV, and the net present value becomes deterministic.
The reduced switch count quasi-Z-source three-level inverter (RSC-QZS-TLI) not only maintains the advantages of continuous input current in the conventional quasi-Z-source three-level inverter ...(C-QZS-TLI), but also reduces the number of power switches and system cost. However, it inevitably faces the challenges of high common-mode voltage (CMV) and neutral-point voltage (NPV) imbalance, which threaten system safety and reliability. Moreover, due to the inherent features of this topology, the medium vectors cannot be generated, which means that the traditional modulation method is not applicable any more. To address the above challenges, a novel modulation method is proposed. The pre-selected basic vectors are optimized primarily, which restrict the CMV magnitude within one-sixth of dc-link voltage. Then, for the particularity of RSC-QZS-TLI, the distribution factor of small vector and its limitation range are introduced for the first time, and an indirect calculating approach is developed to obtain the duty cycles of the pre-selected four vectors, which maintains the correct ac output voltage and dc voltage boosting ability. Meanwhile, according to sector number and output of NPV controller, the distribution factor is modified to control the NPV balance. Compared with the traditional modulation method, the CMV magnitude of the proposed method is reduced by 50 %, and the balanced NPV is controlled actively. Simulated and experimental results verify the feasibility of the proposed scheme.
In June 2018, the ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) mission was launched to measure plant temperatures and better understand how they respond to stress. ...While the ECOSTRESS mission delivers imagery with ~60 m spatial resolution, it is often useful to have spectra at the leaf level in order to explain variability seen at the pixel level. As it was originally titled, the Advanced Spaceborne Thermal Emission Reflection Radiometer (ASTER) spectral library version 2.0 has been expanded to support ECOSTRESS studies by including major additions of laboratory measured vegetation and non-photosynthetic vegetation (NPV) spectra. The library now contains 541 leaf visible shortwave infrared (VIS/SWIR) spectra, 472 leaf thermal infrared (TIR) spectra, and 51 NPV VIS/SWIR and TIR spectra. Previously, the library primarily contained VSWIR and TIR laboratory spectra of minerals, rocks, and man-made materials. This new library, containing over 3000 spectra, was renamed the ECOSTRESS spectral library version 1.0 and is publicly available (http://speclib.jpl.nasa.gov). It should be noted that as with the prior versions of the library, the VSWIR and TIR measurements were made with separate instruments with different calibration sources. Care should be taken when combining the data into a seamless spectrum to cover the entire spectral range. The ECOSTRESS spectral library provides a comprehensive collection of natural and man-made laboratory collected spectra covering the wavelength range of 0.35–15.4 μm.
•The ASTER spectral library 2.0 was updated to the ECOSTRESS spectral library 1.0.•The library includes 541 VIS/SWIR and 472 TIR green vegetation spectra.•The library also includes 51 VIS/SWIR and TIR spectra for non photosynthetic vegetation.•Library covers VIS/SWIR and TIR domain (0.35–15.4 μm).•Includes soil, manmade, meteorite, mineral, NPV, rock, vegetation, water/snow/ice
Solar dish (SD) technology is recognized as one of the most efficient solar thermal technologies for electricity generation. Moreover, SD technology has proven its suitability and reliability in ...solar energy potentials areas that are scarce to have water. In this regard, Egyptian western desert occupies an area of more than 65% of the total area of Egypt. It receives some of the highest solar radiation in the world (up to 3.0 MWh/m2/year), making it a prime location for the exploitation of this technology. Then, it is worth to investigate the opportunities of SD power plant for electricity generation. This paper investigates the techno-economic performance of SD power plant under Egypt desert weather condition. Accordingly, the proposed power plant is modeled and simulated using System Advisor Model (SAM). The annual energy and the levelized costs of electricity (LCOE) are calculated based on the annual simulations of 50 MW installed capacity. The profitability of proposed power plant is assessed based on Egypt’s feed in tariff of concentrated solar power (CSP) projects. The proposed location of this power plant is Benban solar power park, near Aswan city in the south of Egypt. This is because the nature of the place is convenient and configured for building solar power plant, as well as its proximity to the Egyptian electricity grid. Furthermore, a sensitivity analysis is conducted to investigate the effect of the main economic variables of the proposed power plant on the LCOE and NPV. The results show that annual energy output of 50 MW is estimated to 105 GWh/year. The LCOE is estimated to 13.38 ¢/kWh. The avoided GHG emissions and fossil fuels usage are equal to about 45 million tons of CO2 emissions and 21.64 thousand tons of equivalent oil (toe) per year (respectively). Furthermore, the results indicate that LCOE and NPV are very highly sensitive to the collector cost.
•A Solar Dish/Stirling power plant is technically and economically investigated.•The solar dish power plant is modeled and simulated in SAM.•The levelized cost of electricity of the power plant estimated to be 13.38 ¢/kWh.•LCOE and NPV are very highly sensitive to the collector cost.
This paper elaborates on an algorithm for finding the optimal size of a photovoltaic (PV) system of a prosumer based on economic factors. The proposed algorithm was developed in the MATLAB ...programming language and is applied to the Croatian case study considering the Croatian legislation regarding prosumers. The proposed algorithm uses load profile, solar radiation, external temperature and PV module technical characteristics as input data. The algorithm considers the impact of electricity generated from the prosumer’s PV system on the price that the prosumer will receive for the energy exported to the grid as well as achieved savings to calculate the economic indicators — Levelized Cost of Electricity (LCOE), Return on Investment (ROI) and Net Present Value (NPV). Based on the calculated economic indicators LCOE, ROI, and NPV, the optimal size of the PV system is selected. The proposed algorithm was applied to two profiles of prosumers (household and industrial) to demonstrate its usefulness. Furthermore, the impact of the time step of input data on the results has been also investigated. Finally, the proposed algorithm is applied to the input data with 15- and 60-minute time steps for the household prosumer and for the industrial prosumer to obtain the optimal size of the PV system considering the calculated economic indicators.
•Optimal sizing of PV systems based on economic indicators.•The resolution of the input data does not over-affect the economic indicators.•Applications of the proposed algorithm to households and industry.•Industrial consumers have a shorter return on investment.•Estimates of PV power production concerning technical and external influences.
This comprehensive study investigates the stage-wise infection dynamics of Nucleopolyhedrovirus (NPV) in fall armyworm, Spodoptera frugiperda (J. E. Smith) larvae across distinct stages of maize crop ...in Panchmahal and Mahisagar districts of Gujarat, India during the kharif season in 2021. The examination of month-wise mean data reveals a pronounced pattern of NPV prevalence, with the highest infection observed during the cob formation stage (28.74 %), followed by flowering and tasseling (20.23 %), and the vegetative stage (13.93 %). Block specific analyses highlight variations in infection rates, with notable differences between districts and stages. Correlation coefficient analysis indicates a significant and positive relationship between specific crop stages and NPV infection. Regression equations are established, demonstrating a positive increase in natural NPV infection during different crop stages. Weather parameter analysis reveals significant correlations between temperature, humidity, sunshine hours, and NPV infection. The phylogenetic analysis of NPV polyhedrin sequences indicates species-specific clustering within S. frugiperda and a broader genus-specific association. Motif pattern analysis identifies conserved motifs in NPV polyhedrins. Protein structure predictions and Molecular docking studies predicted interactions between polyhedrin and chitinase, suggesting a potential role in the insect's defense against NPV. The bioassay results indicated increased susceptibility of early larvae to NPV, emphasizing the potential for optimizing biocontrol strategies. Overall, this study contributes valuable insights into the ecological and molecular aspects of NPV infection dynamics, offering a significance understanding for developing effective pest management strategies and also underscores its significance in promoting sustainable agriculture.
