Exploring the Model Design Space for Battery Health Management

Battery Health Management (BHM) is a core enabling technology for the success and widespread adoption of the emerging electric vehicles of today. Although battery chemistries have been studied in detail in literature, an accurate run-time battery life prediction algorithm has eluded us. Current reliability-based techniques are insufficient to manage the use of such batteries when they are an active power source with frequently varying loads in uncertain environments. The amount of usable charge of a battery for a given discharge profile is not only dependent on the starting state-of-charge (SOC), but also other factors like battery health and the discharge or load profile imposed. This paper presents a Particle Filter (PF) based BHM framework with plug-and-play modules for battery models and uncertainty management. The batteries are modeled at three different levels of granularity with associated uncertainty distributions, encoding the basic electrochemical processes of a Lithium-polymer battery. The effects of different choices in the model design space are explored in the context of prediction performance in an electric unmanned aerial vehicle (UAV) application with emulated flight profiles

An Application of UAV Attitude Estimation Using a Low-Cost Inertial Navigation System

Unmanned Aerial Vehicles (UAV) are playing an increasing role in aviation. Various methods exist for the computation of UAV attitude based on low cost microelectromechanical systems (MEMS) and Global Positioning System (GPS) receivers. There has been a recent increase in UAV autonomy as sensors are becoming more compact and onboard processing power has increased significantly. Correct UAV attitude estimation will play a critical role in navigation and separation assurance as UAVs share airspace with civil air traffic. This paper describes attitude estimation derived by post-processing data from a small low cost Inertial Navigation System (INS) recorded during the flight of a subscale commercial off the shelf (COTS) UAV. Two discrete time attitude estimation schemes are presented here in detail. The first is an adaptation of the Kalman Filter to accommodate nonlinear systems, the Extended Kalman Filter (EKF). The EKF returns quaternion estimates of the UAV attitude based on MEMS gyro, magnetometer, accelerometer, and pitot tube inputs. The second scheme is the complementary filter which is a simpler algorithm that splits the sensor frequency spectrum based on noise characteristics. The necessity to correct both filters for gravity measurement errors during turning maneuvers is demonstrated. It is shown that the proposed algorithms may be used to estimate UAV attitude. The effects of vibration on sensor measurements are discussed. Heuristic tuning comments pertaining to sensor filtering and gain selection to achieve acceptable performance during flight are given. Comparisons of attitude estimation performance are made between the EKF and the complementary filter

SILHIL Replication of Electric Aircraft Powertrain Dynamics and Inner-Loop Control for V&V of System Health Management Routines

Software-in-the-loop and Hardware-in-the-loop testing of failure prognostics and decision making tools for aircraft systems will facilitate more comprehensive and cost-effective testing than what is practical to conduct with flight tests. A framework is described for the offline recreation of dynamic loads on simulated or physical aircraft powertrain components based on a real-time simulation of airframe dynamics running on a flight simulator, an inner-loop flight control policy executed by either an autopilot routine or a human pilot, and a supervisory fault management control policy. The creation of an offline framework for verifying and validating supervisory failure prognostics and decision making routines is described for the example of battery charge depletion failure scenarios onboard a prototype electric unmanned aerial vehicle

Regeneration and preservation of poultry breeds through transplantation procedures on gonadal tissues

Live poultry flocks are costly to maintain, especially for rare breeds in small populations or non-commercial circumstances. One strategy to reduce these costs could be cryopreservation of the chick gonadal tissues and subsequent transplantation into recipients, which would help to maintain the genetic resources of some heritage chicken breeds that are rare and threatened with extinction. Thus, the overall goal of the study was to produce offspring derived from donors of different chicken breeds, including heritage chicken breeds. In our studies, a vitrification-warming procedure was employed to preserve chick gonadal tissues; and a modified transplantation technique was used to regenerate chicken breeds by the production of donor-derived offspring. An assessment of the vitrification-warming procedure was also conducted by using a morphological scoring system and detecting apoptotic cells via caspase-3 immunofluorescence. Additionally, cryoprotective agent (CPA) diffusivity measurements were made to facilitate mathematical prediction of minimally damaging CPA treatments. One significant aspect of this study focused on post-cryopreservation chick ovarian tissue transplantation to address the failures of this procedure in previous studies. The goal of this experiment was to demonstrate that vitrified/warmed one-day-old chick ovarian tissues could be transplanted and developed generally in the different recipient chicken breeds and can produce the donor-derived offspring; in addition, to evaluate the potential of different chicken breeds to receive a donor graft. In particular, two main experiments were conducted on different chicken lines. The first experiment was transplantation between chickens of similar genetic background of Lohmann White (Oldenhof et al.) and Barred Rock (BR). The second experiment was transplantation between chickens of different genetic background Brown Leghorn (BL), BR and BL/BR. The results differed depending on chicken lines. In the first trial, 50% of ovarian tissues were taken from adult recipients derived from donors of fresh and vitrified-warmed BR ovaries. Moreover, one hen appeared to have a donor-derived graft, as well as two of the embryos from this bird showed alleles of the donor bird. In the second trial, BL and BL/BR background could sustain the development of a graft regardless of the genetic background of the donor. However, all these grafts were enclosed by a membrane and had a variety of growth, suggesting some level of rejection by the recipients. The assessment of the vitrification-warming procedure was conducted on one to three-day-old chick testicular and ovarian tissues. Two methods were used to evaluate the damages of the tissues: Periodic Acid Schiff-Hematoxylin (PAS-H) and an immunohistochemistry technique via caspase-3 immunofluorescence. From the first method, the morphological damages were evaluated, based on the morphological grading system. The second method showed the detection of apoptotic cell execution on the gonadal tissues. Overall, the results show that the vitrification-warming procedures affect the cellular integrity of one to three-day-old chicken gonadal tissues through morphological alterations. While the process does not cause more apoptotic cells on testicular tissues, there are some challenges in ovarian tissues for detecting apoptosis. Taken together, these results suggest the need to optimize this preservation technique for long-term storage and the surgery transplantation, especially in chicken ovarian tissues. Finally, to explore possible relationships between CPA (cryoprotectant agent) equilibration and tissue type, experiments were performed to determine the rate of diffusion of three CPAs into chick testes and ovaries. In the future, this diffusion rate can be used with a mathematical model to create an optimal protocol minimizing the toxicity of CPAs and intracellular ice formation, including diminishing gonadal tissue damages. In summary, the studies of this thesis confirmed the potential of the cryopreservation of chicken genetic material through vitrification and the successful subsequent transplantation of the vitrified-warmed gonadal tissues into the appropriate recipients. Additionally, limitations have been described, such as the effects of the vitrification-warming procedure, the rejections from immune responses of recipients, etc. Some solutions were provided, which could increase the efficiency of the strategy to be practical for poultry studies in diverse fields

Major Histocompatibility Complex-B haplotype and ovarian graft response

ABSTRACT: Gonadal tissue transfer is considered one of the best methods to preserve genetic variability. Poultry hosts can receive a gonad from a donor of a different genetic background, sustain the growth of this graft, and produce gametes from it. Unfortunately, the host's strong immune response may significantly reduce the gonadal graft's ability to reach maturity. Our study aimed to evaluate the influence of MHC-B alleles in rejecting a gonadal graft of similar or different genetic backgrounds. In the first experiment, ovarian tissue was transplanted to chicks of similar genetic backgrounds, either Lohmann White (LW) with variable MHC-B or Barred Rock (BR) with fixed MHC-B. The sustained growth of donor ovarian tissues occurred in (4/7 hosts) BR (MHC-B matched) hosts only—one of these graft-positive-BR hens produced eggs derived from the donor ovary. No grafts were recovered when the host and the donor had an LW background (0/9; MHC-B mismatched). In the second experiment, ovarian transplantation was done between chicks of either similar or different genetic backgrounds (Brown Leghorn [BL], BR, and BL/BR F1). The 2 pure lines contained only one MHC-B allele, whereas the F1 heterozygotes had both. All host birds were given a daily dose of an immunosuppressant (mycophenolate mofetil) until maturity. The success rate was assessed by microsatellite genotype confirmation of donor-derived ovaries plus physiological and histological analyses of ovarian grafts. In this second experiment, 11 out of 43 ovarian hosts laid eggs. However, all fertilized eggs from these hens were derived from the remnant host ovarian tissue, not from the donor ovaries. A necropsy assessment was done on all 43 host birds. Ten donor grafts were recovered from hosts having matched (6 hosts) and mismatched (4 hosts) MHC-B, and none were functional. Interestingly, 6 of them were enclosed by a serous membrane capsule filled with fluid and had various tissue growth. In addition, clusters of immune cells were observed in all recovered donor grafts. Our results demonstrated that genetic background could greatly influence the success of gonadal transfer in chickens

<i>Fusarium foetens</i> AQF6 Isolated from <i>Amentotaxus ynnanensis</i> H.L.Li as a Prolific Source of Antioxidant Compounds

Amentotaxus yunnanensis H.L.Li is a threatened conifer distributed only in China, Laos, and Vietnam, whose fungal endophytes have not been exploited yet. The aims of this study were to screen and characterize antioxidant metabolites from endophytic fungi obtained from A. yunnanensis. Using the surface sterilization method, sixteen endophytic fungi were isolated from A. yunnanensis and classified into seven genera including Fusarium, Penicillium, Aspergillus, Diaporthe, Neopestalotiopsis, Purpureocillium, and Simplicillium through the analysis of Internal Transcribed Spacer (ITS) gene sequences. Among the ethyl acetate crude extracts, Fusarium foetens AQF6 contained the highest amount of polyphenol (117.76 ± 0.94 mg gallic acid equivalent/g) and flavonoid (169.01 ± 2.09 mg quercetin equivalent/g). Importantly, 400 µg/mL AQF6 extract exhibited 95.75 ± 1.1% and 85.66 ± 1.91% of 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radical-scavenging activities, respectively. Chemical investigation led to the isolation and identification of a new bisabolane-type sesquiterpene fusafoetriol (FUS) and 14 known compounds, among which six pure compounds showed free-radical scavenging activity against DPPH and hydroxyl radicals. Under H2O2 stress, the yeast model Saccharomyces cerevisiae treated with 4 mM FUS showed 43.31% increase in viability. FUS has the potential to be applied in nutraceutical, pharmaceutical and food technological applications. Thus, this is the first report demonstrating the presence of endophytic fungi inhabiting A. yunnanensis and their potential as a prolific source of antioxidant metabolites