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The novel orthogonal frequency division multiplexing with subcarrier number modulation (OFDM-SNM) transmission scheme offers high spectral and energy efficiency compared to the conventional OFDM; this is due to the extra information bits loaded over the active subcarriers. However, the OFDM-SNM scheme has a high and comparable peak-to-average power ratio (PAPR) performance to the classical OFDM. Besides the high PAPR in OFDM-SNM, out-of-band emission (OOBE) often happens between the adjacent blocks. To address the above-mentioned problems, we introduce an enhanced version of the classical OFDM-SNM, where the active subcarriers’ positions are cleverly placed to reduce the PAPR and OOBE values. Power spectral density (PSD) and complementary cumulative distribution function (CCDF) of PAPR are used as performance metrics to assess the PAPR and OOBE performances of the proposed scheme. The obtained simulation results exhibit improved PAPR and OOBE performances of the proposed scheme along with almost similar bit error rate (BER) performance as compared to the classical OFDM.

Driven from investments toward net zero transition global interest in fusion energy is growing. This policy perspective addresses challenges for its commercialization, given the potentially long timeframe to deployment and competing/complementary technologies. We focus on magnetically confined fusion power, specifically tokamaks, as the route to commercialization is clearer and there is some cost data available. For fusion to be competitive beyond 2040, costs will likely need to be at or below ∼$80–100/MWh at 2020 price. This will be hard to achieve for early fusion designs both small or large, for which modelling shows energy costs will be greater than $150/MWh even accounting for production learning. This is due to the low power availability from pulsed operation; frequent replacement of vessel components; and low efficiency power cycles. Technology improvements to improve both cycle efficiency and power availability, along with production standardization and long-life components, have the potential to reduce generation costs and enable magnetically confined fusion to be commercially viable. We therefore recommend focusing commercialization efforts on plants with higher thermal efficiency and potential for higher availability as these maximize the probability of fusion energy proving commercially viable. We also recommend that fusion energy be deployed within a proportionate regulatory regime that recognizes its relatively low radiological hazard. Finally, construction of fusion reactors should be planned in fleet/program terms, as commitment to constructing many units will be necessary for it to become commercially viable.

AbstractWith growing demand for internationally traded biomass, the logistic operations required to economically move biomass from the field or forest to end‐ users have become increasingly complex. To design cost effective and sustainable feedstock supply chains, it is important to understand the economics, energy and greenhouse gas (GHG) emissions, their interdependencies, and the related uncertainties of the logistic process operations of international supply chains. This paper presents an approach to assessing lignocellulosic feedstock supply systems at the operational level. For this purpose, the Biomass Logistic Model (BLM) has been linked with the Geographic Information Systems‐based Biomass Intermodal Transportation Model (BIT‐UU) and extended with inter‐continental transport routes. Case studies of herbaceous and woody biomass, produced in the US Midwest and US Southeast, respectively, and shipped to Europe for conversion to Fischer‐Tropsch (FT) diesel are included to demonstrate how intermodal transportation and, in particular, overseas shipping integrates with the bioenergy supply chains. For the cases demonstrated, biomass can be supplied at 99 € Mg−1 to 117 € Mg−1 (dry) and converted to FT diesel at 19 € GJ−1 to 24 € GJ−1 depending on the feedstock type and location, intermediate (chips or pellets) and size of the FT diesel production plant. With the flexibility to change the design of supply chains as well as input variables, many alternative supply chain cases can be assessed. © 2014 Society of Chemical Industry and John Wiley & Sons, Ltd

For layered oxide cathodes, aluminum doping has widely been shown to improve performance, particularly at high degrees of delithiation. While this has led to increased interest in Al-doped systems, including $\mathrm{LiNi_{0.8}Co_{0.15}Al_{0.05}O_{2}}$ (NCA), the aluminum surface environment has not been thoroughly investigated. Using hard x-ray photoelectron spectroscopy measurements of the Al 1s core region for NCA electrodes, we examined the evolution of the surface aluminum environment under electrochemical and thermal stress. By correlating the aluminum environment to transition metal reduction and electrolyte decomposition, we provide further insight into the cathode-electrolyte interface layer. A remarkable finding is that Al-O coatings in LiPF$_6$ electrolyte mimic the evolution observed for the aluminum surface environment in doped layered oxides. ECS transactions 80(10), 197 - 206 (2017). doi:10.1149/08010.0197ecst Published by Pennington, NJ

Environmental science & technology 57(44), 17011 - 17021 (2023). doi:10.1021/acs.est.3c05017 Published by American Chemical Society, Columbus, Ohio

Recent studies and reports suggest an increased mortality rate of undocumented border crossers (UBCs) in Arizona is the result of heat extremes and climatic change. Conversely, others have shown that deaths have occurred in cooler environments than in previous years. We hypothesized that human locomotion plays a greater role in heat-related mortality and that such events are not simply the result of exposure. To test our hypothesis, we used a postmortem geographic application of the human heat balance equation for 2,746 UBC deaths between 1990 and 2022 and performed regression and cluster analyses to assess the impacts of ambient temperature and exertion. Results demonstrate exertion having greater explaining power, suggesting that heat-related mortality among UBCs is not simply a function of extreme temperatures, but more so a result of the required physical exertion. Additionally, the power of these variables is not static but changes with place, time, and policy.

This paper has develop a control strategy in order to control the reactive active power supplied by renewable energy resources (RESs) to enhance grid voltage stability. The grid considered is a microgrid with large-scale photovoltaic (PV) and fuel cell (FC) generators. The system was tested under load disturbances and sun radiation variation. The stability of the voltage improved at the load bus. The study showed the effectiveness of adding FC (dispatchable source) to a microgrid in order to regulate the voltage. The effectiveness of the proposed controller was verified using MATLAB/SIMULINK.

Drug-facilitated sexual assault (DFSA) and drug-facilitated crime (DFC) constitute a mode of violence that is generally unknown to the population and may go unnoticed by health professionals. The aim of this systematic review was to analyze the victims of DFC, compiling their sociodemographic characteristics, the toxic substances used and their biological matrices and modes of action, in order to identify the substances that are commonly put to criminal use. The aim would be to establish political and health strategies that inform and warn people about possible criminal social behaviors consequent danger to health. This systematic review was conducted following the PRISMA guidelines. Alcohol, benzodiazepines and cocaine were among the most commonly detected substances. In most of the hospitals, immunoassays, liquid chromatography (LC-MS), or gas chromatography-mass spectrometry (GC-MS) analyses were used to identify the substances, while the most frequently used biological matrices were blood and urine. From a judicial point of view, the instrumental protocols and techniques followed for the detection of toxics in different biological matrices must guarantee the reliability and validity of the results for use in a court of law. The recommendations of international organizations should be followed and must be called upon to strengthen their respective national laws against this chemical submission (CS) phenomenon.