Finite element analysis using NASTRAN applied to helicopter transmission vibration/noise reduction

A finite element NASTRAN model of the complete forward rotor transmission housing for the Boeing Vertol CH-47 helicopter was developed and applied to reduce transmission vibration/noise at its source. In addition to a description of the model, a technique for vibration/noise prediction and reduction is outlined. Also included are the dynamic response as predicted by NASTRAN, test data, the use of strain energy methods to optimize the housing for minimum vibration/noise, and determination of design modifications which will be manufactured and tested. The techniques presented are not restricted to helicopters but are applicable to any power transmission system. The transmission housing model developed can be used further to evaluate static and dynamic stresses, thermal distortions, deflections and load paths, fail-safety/vulnerability, and composite materials

The influence of siblings on young children's understanding of fluid intake

BACKGROUND: Children need to drink enough water (1.1-1.3 litres) throughout the day to stay hydrated and for health benefits1. Wellbeing and cognitive function benefits have been identified for children who are hydrated2. Yet there is a dearth of research focusing specifically on children’s perceptions of their own fluid intake levels and who helps support them in ensuring they are drinking enough water, this is a novel area to investigate. Previous research3 identified that 44.2% of young children’s fluid intake were influenced the strongest by a family member. This paper will explore in further detail the influence of siblings on children’s fluid intake, in particular older versus younger siblings. METHODS: 130 children (67 girls and 63 boys, of which 45 had a younger sibling (s) and 85 having an elder sibling (s), from 4 primary schools in the South East of England, were questioned between January and April 2019 using an adapted version of Coppinger and Howells’ (2019)4 questionnaire, on their understanding of fluid intake, how much they perceived they drank and who supported them in prompting them to drink. Physical visual representations were used to aid question comprehension and to ensure the questions were appropriate for young children. The data was analysed using SPSS 24.0 using MANOVAs (P < 0.05) to consider statistical variance in gender and older sibling status. RESULTS: The most significant results were linked to elder siblings influence younger siblings in drinking too little fluids within a school day (F=0.530, p<0.05), whilst those without an elder sibling, thought they drank beyond the daily recommended guidelines and reported they drank over 2 litres. This illustrates that children misunderstand fluid intake recommendations regardless of whether they have an elder sibling or not. Children named adults, both parents and teachers as well as elder siblings as the key influencers of them drinking (F=3.67, p<0.05) and the data indicated that girls were more influenced by siblings than boys, whilst twins were not influenced by each other. CONCLUSION: It is concluded that siblings do have an influence on the consumption of water, as siblings act as role models and other siblings follow their habits, therefore the whole family unit is important to ensure that the right fluid intake is consumed. It is recommended that further education, curriculum and community development is needed to continue to support young children’s knowledge and understanding of fluid intake

Young children's understanding of fluid intake

BACKGROUND Coppinger and Howells’ (2019) previously completed an International comparison between primary schools in Ireland and England focusing on children’s understanding of fluid intake. They identified that children under 11 years did not understand the amount of fluid they need each day for good health. Within their sample there was only a limited number of children who were aged 4 – 5 years. This research focuses on this particular age phase and further questions if young children understand fluid intake. METHODS 130 children (63 boys and 67 girls, of which 83 were aged 4 and 47 were aged 5) from 4 elementary schools in the South East of England were questioned between January and April 2019 using an adapted version of Coppinger and Howells’ (2019) questionnaire on their understanding of fluid intake and how much they perceived they drank and who supported them in prompting them when to drink. The adaptions were to ensure the questionnaire was age appropriate for younger age range, and included physical visual representations to aid question comprehension. RESULTS 46.9% of children felt they consumed 500ml or under a day. Only 39.6% responded that they were supported by the teacher, also when children were thirsty, if given the option of playing or stopping rehydration and then playing 33.8% would continue to play without drinking. CONCLUSION Young children in England do not understand fluid recommendations, they were not supported within the school setting by their teacher and more effective resources and strategies are needed to support children’s knowledge

4 and 5 year olds' understanding of fluid intake within England

Background: Within the England children start school in the September following their fourth birthday. Within the preschool school setting and within the first year of primary school the same early years’ foundation stage curriculum is followed (DfE, 2013). Within this curriculum children are to learn about the importance for good health of physical exercise, and a healthy diet. Previously, Coppinger and Howells’ (2019) completed an international comparison between primary schools in Ireland and England focusing on children’s understanding of fluid intake and found that children under 11 years did not understand the amount of fluid that is needed each day for good health, however, they only had a small sample of children from the 4 – 5 age category. This paper focuses solely on this youngest age range within England’s context of primary (elementary) school as a focused analysis. Methods: The questionnaire used by Coppinger and Howells in their research has been adapted to be aged appropriate for use for 4 and 5 year olds, including physical visual representations to aid understanding of the younger age group. 130 children from 5 different schools, in the same geographical location, were questioned as to their understanding of fluid intake, when they are allowed to drink within the school setting, the barriers that prevent them from drinking and who influences and encourages their fluid intake. Results and Conclusion: Data will be presented according to age, and gender. Data collection was undertaken between January and April 2019. It is hypothesised that the age range of 4 and 5 year olds will not understanding their daily fluid intake needs. It is proposed that this research will give insight to help teachers and practitioners identify what is the current understanding of this age range and how educational materials could help the children, teachers and parents develop the children’s knowledge to drink healthily

Examining trainee therapists\u27 responses to client discussions [of] trauma in psychotherapy: a qualitative analysis

Current psychology literature offers several definitions for trauma as well as recommended psychotherapy approaches. As trauma presentation and impact can vary greatly across individuals, choosing a specific treatment approach can be quite challenging, especially for training therapists whose clinical judgment and experience to guide decision-making is limited. As such, little is understood about how novice clinicians reconcile definitional and treatment model conflicts when providing trauma treatment. This exploratory qualitative study analyzed the trauma treatment sessions of 5 training therapists. The process and content themes that emerged from the training therapists\u27 responses were categorized as follows: (a) establishing a mutual understanding of the client\u27s experience, (b) providing guidance and support, (c) encouraging alternative processing, (d) affecting session flow, (e) coping, and (f) client struggles/difficulty. These findings were discussed within the context of current trauma treatment recommendations. Patterns that emerged in the therapists\u27 responses suggested that in their efforts to process trauma, the trainee therapists provided validation of the clients\u27 experiences, offered guidance and support to examine the trauma in an alternative way, helped them identify coping skills and sources of support, and emphasized client resilience through strength-focused responses; however, in doing so, they inadvertently engaged in a variety of behaviors, such as relying too heavily on facts and thoughts about the trauma, shifting session focus away from the trauma, or using interfering verbalizations (e.g., multiple questions at once), all which appeared to undermine client emotional engagement with traumatic material in the coded sessions. Thus, this study\u27s results suggested that training therapists appear to need to be better educated academically and clinically to identify trauma and common treatment barriers that arise, so that they can better plan and implement effective trauma treatments with a clinical population. Specific supervision and training goals that are objective, skill-based, and potentially can be used to enhance training therapists\u27 clinical treatment of trauma, are offered. Future research appears needed to identify what components of recommended trauma treatment training therapists are using, including how training therapists apply Cognitive-Behavioral treatments, and elucidate aspects of trauma treatment that may contribute to and prevent therapy dro

Understanding the Big Picture : End-of-life Decisions in the PICU

Objective: Describe critical care providers\u27 cognitive constructions or their interpretation of the process of decision-making that influences both the technique of conversations and the recommendations given to parents regarding limitation or withdrawal of life sustaining treatments from terminally ill children in the PICU. Design: Qualitative Medical Ethnography. Setting: Tertiary care children\u27s hospital affiliated with a college of medicine. Participants: Eleven critical care providers in the department of pediatrics (attending physicians, critical care fellows, pediatric nurse practitioners, physician assistants). Interventions: In depth, semi-structured interviews designed to explore the experiences of providers in the participation of end-of-life care decision-making. Measurements and Main Results: Findings from the data included concepts and themes that were then organized into a conceptual framework to help understand the decision making process for critically ill children at the end of life. The four major themes identified were: Expectations and Perspectives, Communication Enhancers and Inhibitors, Decision Enablers and Barriers, and Conversation Mechanics. Each theme consists of several concepts from the data that further inform the process. The Expectations and Perspectives theme explains differences between parents and providers that, if understood, can be managed more effectively. The themes focused on communication and decisions elucidate concepts that will improve the process and concepts that have been identified as barriers. The Conversation Mechanics theme provides insight into the process of acquiring the skills that providers have experienced. Conclusions: After conducting in-depth interviews with critical care providers who care for children at the end of life1 a conceptual framework is proposed to provide a better understanding of the decision-making process and to suggest interventions to make advancements

An annotated water-filled, and dry potholes dataset for deep learning applications.

Potholes have long posed a challenging risk to automated systems due to their random and stochastic shapes and the reflectiveness of their surface when filled with water, whether it is "muddy" water or clear water. This has formed a significant limitation to autonomous assistive technologies such as Electric-Powered Wheelchairs (EPWs), mobility scooters, etc. due to the risk potholes pose on the user's well-being as it could cause severe falls and injuries as well as neck and back problems. Current research proved that Deep Leaning technologies are one of the most relevant solutions used to detect potholes due to the high accuracy of the detection. One of the main limitations to the datasets currently made available is the lack of photos describing water-filled, rabble-filled, and random coloured potholes. The purpose of our dataset is to provide the answer to this problem as it contains 713 high-quality photos representing 1152 manuall-annotated potholes in different shapes, locations, colours, and conditions, all of which were manually-collected via a mobile phone and within different areas in the United Kingdom along with two additional benchmarking videos recorded via a dashcam

Asymmetric tandem organic solar cells

Organic photovoltaics (OPVs) is an area that has attracted much attention recently as a potential low cost, sustainable source of energy with a good potential for full-scale commercialisation. Understanding the factors that determine the efficiency of such cells is therefore a high priority, as well as developing ways to boost efficiency to commercially-useful levels. In addition to an intensive search for new materials, significant effort has been spent on ways to squeeze more performance out of existing materials, such as multijunction cells. This thesis investigates double junction tandem cells in the context of small molecule organic materials. Two different organic electron donor materials, boron subphthalocyanine chloride (SubPc) and aluminium phthalocyanine chloride (ClAlPc) were used as donors in heterojunctions with C60 to create tandem cells for this thesis. These materials have been previously used for solar cells and the absorption spectra of the donor materials complement each other, making them good candidates for tandem cell architectures. The design of the recombination layer between the cells is considered first, with silver nanoparticles demonstrated to work well as recombination centres for charges from the front and back sub-cells, necessary to avoid a charge build-up at the interface. The growth conditions for the nanoparticles are optimised, with the tandem cells outperforming the single heterojunction architecture. Optical modelling is considered as a method to improve the understanding of thin film solar cells, where interference effects from the reflective aluminium electrode are important in determining the magnitude of absorption a cell can achieve. The use of such modelling is first demonstrated in hybrid solar cells based on a SubPc donor with a titanium oxide (TiOx) acceptor; this system is ideal for observing the effects of interference as only the SubPc layer has significant absorption. The modelling is then applied to tandem cells where it is used to predict the short-circuit current (Jsc) generation of the sub-cells, which is not accessible experimentally. Current-matching is then used to predict the Jsc of the complete tandem device. As a support to the optical modelling, ellipsometry measurements of thin films of ClAlPc are presented. These films of known thickness are analysed to extract the complex refractive index for use in optical modelling calculations. A dependence of the complex refractive index on film thickness and substrate is also noted. Finally, the external quantum efficiency (EQE) technique is considered as applied to solar cells, and an additional method is proposed to characterise current balancing in asymmetric tandem cells under illumination. This technique is verified experimentally by two separate sets of data

Accommodation to hyperpolarization of human axons assessed in the frequency domain

Human axonsin vivowere subjected to subthreshold currents with a threshold-"ZAP" profile (Impedance [ Z: ] A: mplitude P: rofile) to allow the use of frequency domain techniques to determine the propensity for resonant behavior, and to clarify the relative contributions of different ion channels to their low-frequency responsiveness. Twenty-four studies were performed on the motor and sensory axons in 6 subjects. The response to oscillatory currents was tested between 'DC' and 16 Hz. A resonant peak at ~2 to 2.5 Hz was found in the response of hyperpolarized axons, but there was only a small broad response in axons at resting membrane potential (RMP). A mathematical model of axonal excitability developed using DC pulses provided a good fit to the frequency response for human axons, and indicated that the hyperpolarization-activated currentIh, and the slow potassium currentIKsare principally responsible for the resonance. However the results indicate that if axons are hyperpolarized more than -60% of resting threshold, the only conductances that are appreciably active areIhand the leak conductance - i.e., that the activity of these conductances can be studiedin vivovirtually in isolation at hyperpolarized membrane potentials. Given that the leak conductance dampens resonance it is suggested that the -60% hyperpolarization used here is optimal forIh As expected differences between the frequency responses of motor and sensory axons were present and best explained by reduced GKs, up-modulation ofIhand increased persistent Na(+)current,INaP(due to depolarization of RMP) in sensory axons