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Lithium-ion (Li-ion) batteries are an important component of energy storage systems used in various applications such as electric vehicles and portable electronics. There are many chemistries of Li-ion battery, but LFP, NMC, LMO, and NCA are four commonly used types. In order for the battery applications to operate safely and effectively, battery modeling is very important. The equivalent circuit model (ECM) is a battery model often used in the battery management system (BMS) to monitor and control Li-ion batteries. In this study, experiments were performed to investigate the performance of three different ECMs (1RC, 2RC, and 1RC with hysteresis) on four Li-ion battery chemistries (LFP, NMC, LMO, and NCA). The results indicated that all three models are usable for the four types of Li-ion chemistries, with low errors. It was also found that the ECMs tend to perform better in dynamic current profiles compared to non-dynamic ones. Overall, the best-performed model for LFP and NCA was the 1RC with hysteresis ECM, while the most suited model for NMC and LMO was the 1RC ECM. The results from this study showed that different ECMs would be suited for different Li-ion battery chemistries, which should be an important factor to be considered in real-world battery and BMS applications.

The Bethe-Salpeter (BS) amplitude for $\pi N$ scattering is evaluated at the off mass shell points corresponding to the Low Energy Theorems (LET) based on PCAC and current algebra. The results suggest a way of maintaining consistency between BS equation and LET. Comment: 3 pages, 1 Figure, Contribution to QNP2002 Conference, Juelich June 2002

On-board battery consumption, cellular disconnectivity, and frequent handoff are key challenges for unmanned aerial vehicle (UAV) based delivery missions, a.k.a., cargo-UAV. Indeed, with the introduction of UAV technology into cargo shipping and logistics, designing energy-efficient paths becomes a serious issue for the next retail industry transformation. Typically, the latter has to guarantee uninterrupted or slightly interrupted cellular connectivity for the UAV's command and control through a small number of handoffs. In this paper, we formulate the trajectory planning as a multi-objective problem aiming to minimize both the UAV's energy consumption and the handoff rate, constrained by the UAV battery size and disconnectivity rate. Due to the problem's complexity, we propose a dynamic programming based solution. Through simulations, we demonstrate the efficiency of our approach in providing optimized UAV trajectories. Also, the impact of several parameters, such as the cargo-UAV altitude, disconnectivity rate, and type of environment, are investigated. The obtained results allow to draw recommendations and guidelines for cargo-UAV operations. Comment: This paper was presented in IEEE ICC 2021. It was awarded the "Best Paper Award"

Extensive research works have been carried out over the past few decades in the development of simulation tools to predict the thermal performance of buildings. These validated tools have been used in the design of the building and its components. However, limited simulation tools have been developed for modeling of district energy systems, which can potentially be a very laborious and time-consuming process. Besides many associated limitations, providing a realistic demand profile of the district energy systems is not a straightforward task due to high number of parameters involved in predicting a detail demand profile. This paper reports the development of a simplified model for predicting the thermal demand profile of a district heating system. The paper describes the method used to develop two types of simplified models to predict the thermal load of a variety of buildings (residential, office, attached, detached, etc.). The predictions were also compared with those made by the detailed simulation models. The simplified model was then utilized to predict the energy demand of a variety of districts types (residential, commercial or mix), and its prediction accuracy was compared with those made by detailed model: good agreement was observed between the results.

In the breeding of broiler house, the proper use of lighting systems has great influence on the welfare and the productivity of the birds. The objective was to evaluate two artificial lighting systems used in broiler house in terms of the allocative efficiency of luminance. One of the broiler house was closed with black raffia bag (dark house), without thermal insulation (NTI) and its lighting was composed of incandescent, compact fluorescent light (LFCs) and light emitting diode (LED) bulbs. The other broiler house was closed with extruded polystyrene panels (XPS) and thermally insulated (TI), and its lighting was composed of compact fluorescent lamps. The influence of external light of sun inside the broiler house was analyzed by means of exhaust holes and the degree of distribution of illumination through statistical analyzes and the study of the distribution uniformity coefficient (DUC). Contour maps were prepared showing the degree of internal luminance distribution for each broiler house, specifically in the area that did not suffer interference from external natural sunlight. The results showed that natural lighting influenced the internal lighting across the last 18 meters at the end of the broiler house and there was a more homogeneous lighting in the broiler house TI. Al criar pollos de engorde, el uso adecuado de los programas de iluminación es un factor que influye directamente en el bienestar y la productividad de las aves. Así, el objetivo de este trabajo fue evaluar dos sistemas de iluminación artificial utilizados en aviarios de pollos de engorde, en cuanto a su eficiencia de iluminación distributiva. Uno de los aviarios se cerró con un sistema convencional de lona de rafia oscura (Dark house), sin aislamiento térmico (N.ISO) y su sistema de iluminación consistió en lámparas incandescentes, fluorescentes compactas y LED. La otra casa se cerró con isopaneles de poliestireno extruido (XPS), y se aisló térmicamente (ISO) y su sistema de iluminación estaba compuesto únicamente por lámparas fluorescentes compactas. Se analizó la extensión de la influencia de la luz solar externa al interior de la vivienda, a través de los extractores, y el grado de distribución de la iluminación en las viviendas mediante el análisis estadístico y el estudio del coeficiente de uniformidad de distribución (CUD). Se elaboraron mapas de isolíneas que muestran el grado de distribución de iluminancia interna de cada vivienda, concretamente en la zona que no sufrió interferencias de la luz solar natural externa. Los resultados mostraron que la luz solar natural externa influyó en la iluminación interior durante los últimos 18 metros al final de la casa y la iluminación fue más homogénea en la casa ISO. Na criação de frangos de corte o uso adequado de programas de iluminação é um fator que influencia diretamente o bem-estar e a produtividade das aves. Assim, o objetivo deste trabalho foi avaliar dois sistemas de iluminação artificial utilizados em aviários de frango de corte, quanto à sua eficiência distributiva de iluminamento. Um dos aviários foi fechado com sistema convencional de lona de ráfia escura (Dark house), sem isolamento térmico (N.ISO) e seu sistema de iluminação foi composto por lâmpadas incandescentes, fluorescente compacta e led. O outro aviário foi fechado com isopainéis de poliestireno extrudado (XPS), e isolado termicamente (ISO) e seu sistema de iluminação foi composto somente por lâmpadas fluorescente compacta. Foram analisados o alcance da influência da luz solar externa para o interior do aviário, por meio dos exaustores, e o grau de distribuição da iluminação nos aviários por meio de análises estatísticas e do estudo do coeficiente de uniformidade de distribuição (CUD). Foram elaborados mapas de isolinhas mostrando o grau de distribuição de iluminância interna para cada aviário, especificamente na área que não sofreu interferência da iluminação solar natural externa. Os resultados mostraram que a iluminação solar natural externa influenciou a iluminação interna ao longo dos últimos 18 metros no final do aviário e a iluminação foi mais homogênea no aviário ISO.

The transfection efficiency (TE) of chitosan–plasmid DNA (pDNA) polyplexes can be critically modulated by the polymer degree of deacetylation (DDA) and molecular weight (MW). This study was performed to test the hypothesis that the TE dependence on chitosan MW and DDA is related to the polyplex stability, hence their intracellular decondensation/unpacking kinetics. Major barriers to nonviral gene transfer were studied by image-based quantification. Although uptake increased with increased DDA, it did not appear to be a structure-dependent process affecting TE, nor was nuclear entry. Colocalization analysis showed that all chitosans trafficked through lysosomes with similar kinetics. Fluorescent resonant energy transfer (FRET) analysis revealed a distinct relationship between TE and polyplex dissociation rate. The most efficient chitosans showed an intermediate stability and a kinetics of dissociation, which occurred in synchrony with lysosomal escape. In contrast, a rapid dissociation before lysosomal escape was found for the inefficient low DDA chitosan whereas the highly stable and inefficient complex formed by a high MW and high DDA chitosan did not dissociate even after 24 hours. This study identified that the kinetics of decondensation in relation to lysosomal escape was a most critical structure-dependent process affecting the TE of chitosan polyplexes.

Abstract 35Cl nuclear quadrupolar resonance linewidth and spin-lattice relaxation time and 19F nuclear magnetic resonance lineshape and spin-lattice relaxation time measurements are reported for polycrystalline trichlorofluoromethane over the temperature range 80 to 160 K. The possibility of lattice vacancies as a mechanism for the 35Cl line broadening and the nuclear relaxation is discussed and rejected. It is concluded that the dominant motional mechanism above 120 K is the reorientation of the molecules around the threefold axis characterized by an activation energy of 27.2 kJ mol−1. A two-exponential analysis of the 19F nonexponential relaxation gives almost the same activation energy. The 19F lineshape shows a structure suggesting that the molecules arrange themselves in a very different way than they do in related CYX3 compounds.

This paper develops enhanced hybrid generic (nonlinear) models of Type-3 and Type-4 wind power plants (WPPs) and extracts the corresponding linear (small-signal) dynamic models for power system transient stability analysis. The models are hybrid in nature since they consider both continuous states and discrete logic-controlled variables. The introduced enhancements include (i) a freezing function to reactivate reactive power emulator of Type-3 and Type-4 WPPs, (ii) active-current command recalculation step for Type-3 WPP and (iii) elimination of an activating logic of PI-controller limits in real current control path. The main feature of the enhanced models is that they can replicate the field-verified responses of the built-in PSS/E software models in any adopted software platform. It should be noted that the generic models described in the technical literature do not necessarily provide such replication. The paper also deduces small-signal dynamic models of Type-3 and Type-4 WPPs and addresses the multiple eigen structures of the linearized enhanced generic model of Type-3 WPP, which has not been comprehensively discussed in the technical literature. The enhanced nonlinear hybrid models and the corresponding linearized models are evaluated and verified based on time-domain simulation studies in PSS/E and MATLAB platforms, using NPCC system as the test bed.