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This paper covers the development of a new reduced order model for supersonic flow fields. The name of the method is the small disturbance streamline method. Its purpose is to model the unsteady fl...

This paper provides a high-level review of the potential failure modes and hazards to which electrified aircraft propulsion (EAP) systems are susceptible, along with potential gas turbine control-based strategies to assist in the mitigation of those failures. To introduce the types of failures that an EAP system may experience, a generic EAP system is considered, consisting of gas turbine engines, mechanical drives, electric machines, power electronics and distribution systems, energy storage devices, and motor driven propulsors. The functionality provided by each of these EAP subsystems is discussed, along with their potential failure modes, and possible strategies for mitigating those failures. To further illustrate the role of gas turbine controls in mitigating EAP failure modes, an example based on a simulated EAP concept aircraft proposed by NASA is given. The effects of failures are discussed, along with turbomachinery control strategies, including reversionary control modes, and control limit logic.

The paper considers a generic model for a turbofan engine coupled to electromechanical (EM) elements used for energy conversion and storage in electric form. The electromechanical systems apply torque to the engine shafts, allowing for controllable power injection or extraction to and from the engine. The standard proportional-integral (PI) control law used to command fuel flow for turbofan speed regulation is maintained for compatibility with industry practices, leaving the electromechanical torque to be specified. The paper adopts an optimal control approach for this purpose, where a weighted combination of electric energy consumption and fuel consumption is minimized subject to the dynamics of the electrified propulsion system. The solution for the optimal torques is given by linear state feedback plus bias, with gains calculated numerically from engine linearization data. Energy balance equations are derived and used to guide the optimization, evaluate the resulting power distributions, and check for errors. Simulation studies are presented for a chop-burst transient and for a realistic flight mission profile with environmental input variations. The paper shows the economic advantage of operating the engine with the electrified components. Specifically, fuel burn can be reduced in exchange for electric energy, which must be replenished, but at lower cost.

This paper examines a distinctive aspect of the important theme of vision in Vladimir Nabokov’s work—the pleasure that one person may derive from observing another person, often of the opposite sex. While many episodes of voyeurism or scopophilia involve a male character spying on a female character, Nabokov likes to complicate or even subvert this pattern, creating scenes in which males watch other males, or females take control of the gaze and observe male characters. The paper explores the delights and the discomforts that one might derive in Nabokov’s fictional world from spying on another, depending on whether one is the observer or the observed. While fully aware of the pleasure that some of his male characters gain from looking at a female figure from a safe distance, Nabokov enjoys destabilizing this impulse through parody, satire, and exaggeration, creating a rich portrait of human desire, longing, and frustration.

Electrified aircraft propulsion (EAP) systems hold potential for the reduction of aircraft fuel burn, emissions, and noise. Currently, NASA and other organizations are actively working to identify and mature technologies necessary to bring EAP designs to reality. This paper specifically focuses on the envisioned control technology challenges associated with EAP designs that include gas turbine technology. Topics discussed include analytical tools for the dynamic modeling and analysis of EAP systems, and control design strategies at the propulsion and component levels. This includes integrated supervisory control facilitating the coordinated operation of turbine and electrical components, control strategies that seek to minimize fuel consumption and lessen the challenges associated with thermal management, and dynamic control to ensure engine operability during system transients. These dynamic control strategies include innovative control approaches that either extract or supply power to engine shafts dependent upon operating phase, which may improve performance and reduced gas turbine engine weight. Finally, a discussion of control architecture design considerations to help alleviate the propulsion/aircraft integration and certification challenges associated with EAP systems is provided.

Background: The COVID-19 pandemic has impacted many aspects of the practice of oncology around the world. COVID was first detected in Ireland on 29/2/20. Many oncology units saw dramatic changes in activity in the face of rising infection rates. We aim to assess compare pharmacy activity, day unit systemic therapy adminstration and nursing staffing levels during the pre- and COVID periods. Methods: Hospital information systems were used to retrieve numbers of patients attending, numbers and types of items dispensed by pharmacy, and available nurses to deliver the systemic therapies from March 2019 to Feb. 2021. The data was analysed to identify trends in prescribing and dispensing practices for this period. Supportive medications such as anti-emetics, bisphosphosphonates were not included. Subgroup analysis on numbers of chemotherapy, immunotherapy, monoclonal antibody drugs dispensed per month was performed. A paired t-test was used to compare means. Results: 9410 non-clinical trials and 411 clinical trials items were dispensed from March 2019 until February 2020 (pre-COVID) for 11,606 patient attendances. From March 2020 until February 2021 (COVID period), 8931 non-clinical trials and 826 clinical trials items were dispensed for 10818 patient attendances. The mean number of non-clinical trials items dispensed per month were 784 and 744 respectively, with no statistical difference being found (p=0.11). There was a doubling in the number of clinical trials agents dispensed. The mean number of nurses available to administer therapies per day was 5.7 (SD=0.78) compared to the projected 7.8 WTE (whole time equivalents) ideally required. [Formula presented] Conclusions: Despite COVID restrictions it was possible to administer comparable numbers of cancer treatments throughout the COVID period, when compared to the previous year despite modest nursing staff numbers due to the dedication and selflessness of nursing, oncologists and oncology pharmacy staff. Legal entity responsible for the study: The authors. Funding: Has not received any funding. Disclosure: All authors have declared no conflicts of interest.

Background Much of the work of a busy oncology day unit is undocumented, especially the work involved in phone triage during the working hours of 8am to 6pm. Phone calls from patients, their family doctors, palliative care teams, or from within the Hospital itself seeking advice form the majority of this aspect of the Specialist Oncology Nurse and Staff Nurses’ time. This project was performed to assess the nature of these calls and the broad advice given to the callers so that a dedicated Acute Review Specialist Oncology Nurse Clinic could be developed. Methods In conjunction with key oncology nurses and their medical oncologist colleagues a log to capture each answered call was developed. This centred on the date and time of the call, the source, the issue raised, the advice given, if advised to go to the Emergency Room the reason why, and other actions that were necessary. A form was completed per answered call, and collected at the end of the day. Data was recorded on a spreadsheet. All forms were annonymised with regard to patient identifiers. The forms were focused on whether the issue was successfully addressed within the day unit, the Hospital’s emergency room, the community services, or whether solely by the advice given over the telephone. Results A sample size of 252 incoming answered calls by the Oncology Nursing Staff to the Nurses’ station was analysed. Just over half these calls (52%) were made by patients/family members. Other calls related to internal questions such as from Interventional Radiology or other diagnostic areas of the Hospital (26%), pharmacies (7%), and family doctors (4%). The other 11% of calls were mainly from wards relating to advice on inpatients or seeking consults. Of the unwell patients calling for advice, near half (48%) were seeking advice on what action to take: stay at home or come to Hospital. 35% of patients were seeking either a new appointment or change in appointment date. The remaining 17% of patients were seeking non-emergency review by the medical oncology team. Conclusions This analysis of answered calls highlights the need for involvement of experienced oncology nurses in the triage of phone calls to a busy oncology day unit, and the need to develop an Acute Review Clinic, managed by an experienced oncology nurse specialist. Legal entity responsible for the study Beaumont Hospital Cancer Centre. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.

BackgroundThe frequency of full syndromal and subsyndromal delirium is understudied.AimsWe conducted a point prevalence study in a general hospital.MethodPossible delirium identified by testing for inattention was evaluated regarding delirium status (full/subsyndromal delirium) using categorical (Confusion Assessment Method (CAM), DSM-IV) and dimensional (Delirium Rating Scale-Revised-98 (DRS-R98) scores) methods.ResultsIn total 162 of 311 patients (52%) screened positive for inattention. Delirium was diagnosed in 55 patients (17.7%) using DSM-IV, 52 (16.7%) using CAM and 58 (18.6%) using DRS-R98⩾12 with concordance for 38 (12.2%) individuals. Subsyndromal delirium was identified in 24 patients (7.7%) using a DRS-R98 score of 7–11 and 41 (13.2%) using 2/4 CAM criteria. Subsyndromal delirium with inattention (v. without) had greater disturbance of multiple delirium symptoms.ConclusionsThe point prevalence of delirium and subsyndromal delirium was 25%. There was modest concordance between DRS-R98, DSM-IV and CAM delirium diagnoses. Inattention should be central to subsyndromal delirium definitions.

An article originally published in the International Journal of Industrial Ergonomics in 1991 discussed the effects of damaging noise levels exposed during the leisure time of industrial workers. With a noise level change preferences, this study was designed to work in collaboration with a 2013 study (Claire Drummond, 2013) which began the groundwork of measuring and examining the consistency of the data collected in 1990. Attributed to an increase in popularity of electronic music and improved digital sound equipment, indoor leisure environment sound levels have increased since the original study. The purpose of this study is to expand the collection of data on exposure levels in current leisure activities reported in the 2012 study to enhance the statistical significance that levels are indeed higher than the noise level preferences and tolerances specified by the Occupational Health and Safety Administration (OSHA) and International Standards Organization (ISO) guidelines. With strenuous legal standards, industries have taken substantial steps to follow the OSHA and ISO recommended guidelines; however, places of leisure such as bars, movie theaters, churches, and sporting events are not required to adhere to the same standards. The noise data was collected using a Quest SPL (2800) calibrated dosimeter. This device is a great improvement from the GenRad Sound Level Meter originally used in the 1990 study for the fact that the Quest SPL (2800) gives a complete printout at the end of a data run that takes in account the duration and average dose of noise exposure run as well as average and peak noise levels. The GenRad device was limited to measuring low and high noise level readings. Average leisure noise levels by category were as follows: peak levels in a sample of thirty-nine leisure activities: churches and concerts (118.06 dB (σ = 2.62 dB)), bars (117.48 dB (σ = 9.32 dB)), and sporting events (122.99 dB (σ = 10.97 dB)). Following the OSHA and ISO standards, any exposure noise level over 115.00dB exceeds the recommended allowance. Adult industrial workers exposing themselves to these levels after an eight hour workday in an OSHA-controlled environment are exceeding the allowable exposure. Industrial business are spending large sums of money to make sure they are in compliance with OSHA standards yet their employees are potentially permanently damaging hearing due to their choice of leisure activity. These individuals are thus increasing their risk of a permanent threshold shift. As a side observation to the adult exposures, many parents had their children under the age of 4 in attendance at the high level peak level leisure activities. Hearing is fully developed at birth, but extended exposure times to high peak noise levels can cause an earlier permanent threshold shift in children or permanent hearing loss at a younger age.

This paper covers the application of a model-based engine control (MBEC) methodology featuring a self tuning on-board model for an aircraft turbofan engine simulation. The nonlinear engine model is capable of modeling realistic engine performance, allowing for a verification of the advanced control methodology over a wide range of operating points and life cycle conditions. The on-board model is a piece-wise linear model derived from the nonlinear engine model and updated using an optimal tuner Kalman Filter estimation routine, which enables the on-board model to self-tune to account for engine performance variations. MBEC is used here to show how advanced control architectures can improve efficiency during the design phase of a turbofan engine by reducing conservative operability margins. The operability margins that can be reduced, such as stall margin, can expand the engine design space and offer potential for efficiency improvements. Application of MBEC architecture to a nonlinear engine simulation is shown to reduce the thrust specific fuel consumption by approximately 1% over the baseline design, while maintaining safe operation of the engine across the flight envelope.

This paper discusses the design and implementation of an extended Kalman filter (EKF) for model-based engine control (MBEC). Previously proposed MBEC architectures feature an optimal tuner Kalman Filter (OTKF) to produce estimates of both unmeasured engine parameters and estimates for the health of the engine. The success of this approach relies on the accuracy of the linear model and the ability of the optimal tuner to update its tuner estimates based on only a few sensors. Advances in computer processing are making it possible to replace the piece-wise linear model, developed off-line, with an on-board nonlinear model running in real-time. This will reduce the estimation errors associated with the linearization process, and is typically referred to as an extended Kalman filter. The non-linear extended Kalman filter approach is applied to the Commercial Modular Aero-Propulsion System Simulation 40,000 (C-MAPSS40k) and compared to the previously proposed MBEC architecture. The results show that the EKF reduces the estimation error, especially during transient operation.

The bicycle is a common, yet unique mechanical contraption in our world. In spite of this, the bike's physical and mechanical principles are understood by a select few. You do not have to be a genius to join this small group of people who understand the physics of cycling. This is your guide to fundamental principles (such as Newton's laws) and the book provides intuitive, basic explanations for the bicycle's behaviour. Each concept is introduced and illustrated with simple, everyday examples. Although cycling is viewed by most as a fun activity, and almost everyone acquires the basic skills at a young age, few understand the laws of nature that give magic to the ride. This is a closer look at some of these fun, exhilarating, and magical aspects of cycling. In the reading, you will also understand other physical principles such as motion, force, energy, power, heat, and temperature.

The bicycle is a common, yet unique mechanical contraption in our world. In spite of this, the bike's physical and mechanical principles are understood by a select few. You do not have to be a genius to join this small group of people who understand the physics of cycling. This is your guide to fundamental principles (such as Newton's laws) and the book provides intuitive, basic explanations for the bicycle's behaviour. Each concept is introduced and illustrated with simple, everyday examples. Although cycling is viewed by most as a fun activity, and almost everyone acquires the basic skills at a young age, few understand the laws of nature that give magic to the ride. This is a closer look at some of these fun, exhilarating, and magical aspects of cycling. In the reading, you will also understand other physical principles such as motion, force, energy, power, heat, and temperature.

The bicycle is a common, yet unique mechanical contraption in our world. In spite of this, the bike's physical and mechanical principles are understood by a select few. You do not have to be a genius to join this small group of people who understand the physics of cycling. This is your guide to fundamental principles (such as Newton's laws) and the book provides intuitive, basic explanations for the bicycle's behaviour. Each concept is introduced and illustrated with simple, everyday examples. Although cycling is viewed by most as a fun activity, and almost everyone acquires the basic skills at a young age, few understand the laws of nature that give magic to the ride. This is a closer look at some of these fun, exhilarating, and magical aspects of cycling. In the reading, you will also understand other physical principles such as motion, force, energy, power, heat, and temperature.

The bicycle is a common, yet unique mechanical contraption in our world. In spite of this, the bike's physical and mechanical principles are understood by a select few. You do not have to be a genius to join this small group of people who understand the physics of cycling. This is your guide to fundamental principles (such as Newton's laws) and the book provides intuitive, basic explanations for the bicycle's behaviour. Each concept is introduced and illustrated with simple, everyday examples. Although cycling is viewed by most as a fun activity, and almost everyone acquires the basic skills at a young age, few understand the laws of nature that give magic to the ride. This is a closer look at some of these fun, exhilarating, and magical aspects of cycling. In the reading, you will also understand other physical principles such as motion, force, energy, power, heat, and temperature.

The bicycle is a common, yet unique mechanical contraption in our world. In spite of this, the bike's physical and mechanical principles are understood by a select few. You do not have to be a genius to join this small group of people who understand the physics of cycling. This is your guide to fundamental principles (such as Newton's laws) and the book provides intuitive, basic explanations for the bicycle's behaviour. Each concept is introduced and illustrated with simple, everyday examples. Although cycling is viewed by most as a fun activity, and almost everyone acquires the basic skills at a young age, few understand the laws of nature that give magic to the ride. This is a closer look at some of these fun, exhilarating, and magical aspects of cycling. In the reading, you will also understand other physical principles such as motion, force, energy, power, heat, and temperature.

The bicycle is a common, yet unique mechanical contraption in our world. In spite of this, the bike's physical and mechanical principles are understood by a select few. You do not have to be a genius to join this small group of people who understand the physics of cycling. This is your guide to fundamental principles (such as Newton's laws) and the book provides intuitive, basic explanations for the bicycle's behaviour. Each concept is introduced and illustrated with simple, everyday examples. Although cycling is viewed by most as a fun activity, and almost everyone acquires the basic skills at a young age, few understand the laws of nature that give magic to the ride. This is a closer look at some of these fun, exhilarating, and magical aspects of cycling. In the reading, you will also understand other physical principles such as motion, force, energy, power, heat, and temperature.

The bicycle is a common, yet unique mechanical contraption in our world. In spite of this, the bike's physical and mechanical principles are understood by a select few. You do not have to be a genius to join this small group of people who understand the physics of cycling. This is your guide to fundamental principles (such as Newton's laws) and the book provides intuitive, basic explanations for the bicycle's behaviour. Each concept is introduced and illustrated with simple, everyday examples. Although cycling is viewed by most as a fun activity, and almost everyone acquires the basic skills at a young age, few understand the laws of nature that give magic to the ride. This is a closer look at some of these fun, exhilarating, and magical aspects of cycling. In the reading, you will also understand other physical principles such as motion, force, energy, power, heat, and temperature.