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In this article, we develop an integrated approach to energy optimization for an all-electric aircraft. Our approach involves the formulation of the aircraft energy optimization as a set of optimal control problems (OCPs)—integrating battery and flight dynamics—for the cruise and climb phases, as well as the complete flight profile. The corresponding OCPs are then examined in the context of Pontryagin's minimum principle, providing necessary optimality conditions for the proposed integrated approach. Our analysis is then followed by utilizing the numerical solver Tomlab to devise computational solutions for the energy optimization OCPs. We then proceed to characterize the performance of the energy-optimal solutions for distinct models of the battery. In particular, we show that the choice of the battery model does not alter the form of optimal control for the flight system; however, the current profiles for the battery pack and the total operating costs are affected by the adopted models used for optimization. Finally, we develop a Simulink model built around physics-based battery dynamics to further characterize the interplay between aircraft energy operating costs and the underlying battery dynamics.

Space research relies heavily on satellites, and technological developments are critical to the success of these missions. In order to estimate satellite pose, a simulation of an IMU sensor using Matplotlib is presented in this study. A roll, pitch, and yaw value analysis is performed on data obtained from the BNO-055 IMU sensor. A prototype ground station's helical antenna is used to investigate these parameters. For effective communication between the satellite body and ground station setup, a low-cost transceiver module RF-433Mhz module is connected to the ground station. IMUsensors are essential for inertial measurements in spacecraft, which support ground station monitoring. This study makes use of a four-turn helical antenna that is built for deployment and designed using the 4nec2 simulation program for RF-based satellite-ground station communication. The antenna's VSWR is 1.432, and its directivity is 18.581. Matplotlib is utilized to model variations in roll, pitch, and yaw values. Roll, pitch, and yaw ranges that are observed are −0.375 to 0.25, −0.375 to 0.5625, and −0.3125 to 0.1875, in that order. These ranges are useful in effectively visualizing the body pose of the CubeSat when connecting via PySerial to a Matplotlib-developed program.

Introduction:Monoclonal gammopathy of undetermined significance (MGUS) is the presence of a monoclonal immunoglobulin without concurrent lymphoproliferative disease. It is found in about 5% of people aged 50 and older in the general population. Prevalence rates of MGUS increase with age, especially in men and individuals of Black ethnicity compared to women and White individuals, respectively. The diagnostic criteria for MGUS includes a serum M-protein level <3 g/dL, <10% clonal plasma cells in the bone marrow, and the absence of a myeloma-defining event. Though historically considered benign, emerging evidence suggests that MGUS patients, even without lymphoproliferative disorders, face increased risks of various diseases like bone diseases, recurrent infections, autoimmune disorders, peripheral neuropathy, renal complications, and cardiovascular disease (CVD). This study aims to investigate the prevalence and characteristics of individuals with both MGUS and heart failure (HF) and examine potential racial disparities between Black patients and non-Black patients with MGUS and HF.

Background

Most patients who could be cured of sickle cell disease (SCD) with stem cell transplantation do not have a matched sibling donor. Successful use of alternative donors, including mismatched family members, could provide a donor for almost all patients with SCD. The use of a reduced-intensity conditioning regimen may decrease late adverse effects. Ten patients with symptomatic SCD underwent CD34+ cell-selected, T-cell–depleted peripheral blood stem cell transplantation from a mismatched family member or unrelated donor. A reduced-intensity conditioning regimen including melphalan, thiotepa, fludarabine, and rabbit anti-thymocyte globulin was used. Patients were screened for a companion study for immune reconstitution that included a donor lymphocyte infusion given 30-42 days after transplant with intravenous methotrexate as graft-versus-host disease (GVHD) prophylaxis. Seven eligible patients were treated on the companion study. Nine of 10 patients are alive with a median follow-up of 49 months (range, 14-60 months). Surviving patients have stable donor hematopoietic engraftment (mean donor chimerism, 99.1% ± 0.7%). There were no sickle cell complications after transplant. Two patients had grade II-IV acute GVHD. One patient had chronic GVHD. Epstein-Barr virus–related posttransplant lymphoproliferative disorder (PTLD) occurred in 3 patients, and 1 patient died as a consequence of treatment of PTLD. Two-year overall survival was 90%, and event-free survival was 80%. A reduced-intensity conditioning regimen followed by CD34+ cell-selected, T-cell–depleted alternative donor peripheral blood stem cell transplantation achieved primary engraftment in all patients with a low incidence of GVHD, although PTLD was problematic. This trial was registered at clinicaltrials.gov as #NCT00968864.

One of the contributing factors to the aging of lithium-ion batteries is the growth of the solid-electrolyte interphase (SEI) layer. The growth of the SEI layer leads to the irreversible loss of lithium available for cycling and increases the resistance of the battery. Physics-based models in literature model the kinetically limited or solvent diffusion-limited growth. In such models, the interface resistance is a constant, and the contribution to the overpotential of the intercalation reaction from the SEI layer is considered to be ohmic. In this study, we propose a model that describes the growth of the SEI layer on the electrode surface as a moving interface. The transport of lithium ions and the solvent in the electrolyte are affected by this moving interface. The equations that govern the species transport and the potential drop across the SEI layer are derived from dilute solution theory and solved by transforming the coordinates of the moving boundary. The ion transport induces changes in the conductivity across the SEI layer, which affects the potential drop that arises due to its growth. The effects of this potential on capacity fade are studied over cycling the battery.

Understanding the nature of onset and propagation of thermal runaway in a Li-ion battery pack is critical for ensuring safety and reliability. This paper presents thermal runaway simulations to understand the impact of radiative heat transfer on thermal runaway onset and propagation in a pack of cylindrical Li-ion cells during transportation/storage. It is shown that radiative properties of the internal partition walls between cells commonly found in battery packs for transportation/storage play a key role in determining whether thermal runaway propagation occurs or not. Surface emissivity of the internal partitions is shown to drive a key balance between radiative heat absorbed from the trigger cell and emitted to neighboring cells. It is shown that a high thermal conductivity partition may greatly help dissipate the radiatively absorbed heat, and therefore prevent onset and propagation. Therefore, choosing an appropriate emissivity of the internal partitions may offer an effective thermal management mechanism to minimize thermal runaway. Emissivity of the cells is also shown to play a key role in radiative heat transfer within the battery pack. This work contributes towards the fundamental understanding of heat transfer during thermal runaway in a battery pack, and offers practical design guidelines for improved safety and reliability.

The venting of hot gases due to rupture of a Li-ion cell during thermal runaway may rapidly transfer thermal energy to neighboring cells in a battery pack and cause propagation of thermal runaway. While thermal runaway has been studied extensively through both measurements and simulations, there is a relative lack of research on the impact of the venting process on thermal runaway propagation. This work presents a non-linear thermal-fluidic simulation of supersonic turbulent flow of hot gases ejecting from a trigger cell and spreading to neighboring cells. Assuming isentropic flow, temperature and speed of the gas flow as functions of time are estimated based on past measurements. These data are used in simulations to determine the thermal impact of the venting process on neighboring cells. The impact of various geometrical parameters of the battery pack on the spreading of venting gases is investigated. Results indicate that cell-to-cell gap, overhead gap and the location of the vent hole on the cell body strongly influence the nature of propagation of thermal runaway to neighboring cells. This work develops a fundamental understanding of an important process during thermal runaway, and may help in the design and optimization of safe Li-ion battery packs for energy conversion and storage.

There has been significant recent interest in studying multiscale characteristics of current and next-generation batteries, including lithium-metal and lithium-sulfur batteries. Advances in computing power make researchers believe that the detailed multiscale models can be efficiently simulated to arrive at the insights for the degradation and performance loss; however, this is not true and special attention needs to be paid to local singularities, boundary layers, moving boundaries, etc. This article presents 2D examples that illustrate the importance of grid convergence studies, provides well-defined detailed models to test the efficiency of numerical schemes, and discusses the associated simulation challenges.

Thermal management of Li-ion battery packs is a critical technological challenge that directly impacts safety and performance. Removal of heat generated in individual Li-ion cells into the ambient is a considerably complicated problem involving multiple heat transfer modes. This paper develops an iterative analytical technique to model conjugate heat transfer in coolant-based thermal management of a Li-ion battery pack. Solutions for the governing energy conservation equations for thermal conduction and convection are derived and coupled with each other in an iterative fashion to determine the final temperature distribution. The analytical model is used to investigate the dependence of the temperature field on various geometrical and material parameters. This work shows that the coolant flowrate required for effective cooling can be reduced significantly by improving the thermal conductivity of individual Li-ion cells. Further, this work helps understand key thermal–electrochemical trade-offs in the design of thermal management for Li-ion battery packs, such as the trade-off between temperature rise and energy storage density in the battery pack.

Purpose. There are limited resources for long-term specialist follow-up after bariatric surgery. In selected centres, patients can access a postoperative support group, but there is no clear evidence to guide their delivery. Materials and Methods. A retrospective study of bariatric surgery patients (n = 152) who had been discharged from specialist follow-up (mean time since surgery 5.5 years), covering weight history, physical and psychosocial comorbidities, and the need for a postoperative bariatric support group. Results. Fifty-eight percent wanted a postbariatric surgery patient support group. This was not associated with operation type or the amount of weight lost or regained. However, those who wanted a support group were significantly more likely to be struggling to keep the weight off, to be unhappy with the way they look, or to be experiencing difficulties returning to work. Conclusions. These data point to an unmet patient requirement for a postoperative support group that is independent of weight loss success. More research is required to ascertain how such a group should be delivered, but our data would suggest that supporting patients with weight loss maintenance, body image, and return to work is an important part of postoperative care, and these needs extend well beyond the immediate period of specialist follow-up.

The transient source measurement technique is a nonintrusive, nondestructive method of measuring the thermal properties of a given sample. The transient source technique has been implemented using a wide variety of sensor shapes or configurations. The modern transient plane source (TPS) sensor is a spiral-shaped sensor element which evolved from transient line and transient hot strip (THS) source techniques. Commercially available sensors employ a flat interface that works well when test samples have a smooth, flat surface. The present work provides the basis for a new, cylindrical strip (CS) sensor configuration to be applied to cylindrical surfaces. Specifically, this work uses parameter estimation theory to compare the performance of CS sensor configurations with a variety of existing flat sensor geometries, including TPS and THS. A single-parameter model for identifying thermal conductivity and a two-parameter model for identifying both thermal conductivity as well as volumetric heat capacity are considered. Results indicate that thermal property measurements may be carried out with greater measurement sensitivity using the CS sensor configuration than similar configurations for flat geometries. In addition, this paper shows how the CS sensor may be modified to adjust the characteristic time scale of the experiment, if needed.

The performance, safety, and reliability of electrochemical energy storage and conversion systems based on Li-ion cells depend critically on the nature of heat transfer in Li-ion cells, which occurs over multiple length scales, ranging from thin material layers all the way to large battery packs. Thermal phenomena in Li-ion cells are also closely coupled with other transport phenomena such as ionic and charge transport, making this a challenging, multidisciplinary problem. This review paper presents a critical analysis of recent research literature related to experimental measurement of multiscale thermal transport in Li-ion cells. Recent research on several topics related to thermal transport is summarized, including temperature and thermal property measurements, heat generation measurements, thermal management, and thermal runaway measurements on Li-ion materials, cells, and battery packs. Key measurement techniques and challenges in each of these fields are discussed. Critical directions for future research in these fields are identified.