Miracle-dz/UniFAR-FTUs huggingface dataset:
Errors, violations, and reporting behaviour in aviation maintenance

[Abstract]: Descriptive models of how accidents occur are now commonplace in the aviation industry. These models are useful for guiding accident investigation teams and for helping to decide what changes need to be introduced to reduce the possibility of further accidents. However, from a psychological point of view, what is still lacking in the field is an empirical model that links organizational constructs such as safety climate with individual variables such as stress and fatigue and then shows how both of these combine to influence important outcome variables such as workplace violations, errors, and willingness to report incidents and near-misses. The present paper reports on a series of studies conducted within aviation maintenance settings. The first study focussed on the link between safety climate, stress, and maintenance errors. The results suggested that safety climate does not have a direct effect on errors but has a strong indirect effect via psychological stress experienced by individual workers. A second study replicated this finding. A third study extended the model to include workplace violations and demonstrated the importance of measuring management attitudes and group norms when assessing intention to violate and actual violation behaviours. A fourth study has just been completed that introduced a variable labelled as willingness to report. Sections of the path model that were established in earlier studies received further support and a strong link was established between safety climate and willingness to report. The paper concludes with recommendations as to how these empirical findings can be used to support ongoing initiatives in safety training.
Children with overweight are not less physically active than children of normal-weight

Background The aim of this study was to investigate the differences in objectively measured physical activity and in self-reported physical activity between overweight and normal-weight children. Methods Data from a prospective cohort study including children, presenting at the participating general practices in the south-west of the Netherlands, were used. Children (aged 4-15 years) were categorized as normal-weight or overweight using age- and sex specific cut-off points. They wore an ActiGraph accelerometer for one week to register physical activity, and filled out a diary for one week about physical activity. Results A total of 57 children were included in this study. Overweight children spent significantly less percentage time per day in sedentary behavior (β -1.68 (95%CI -3.129, -0.07)). There were no significant differences in percentage time per day spent in light to moderate physical activity (β 1.52 (-0.01, 3.04)), and in moderate to vigorous physical activity (β 0.33 (-0.11, 0.78)). No significant differences were found between children of normal-weight and overweight in self-reported measures of physical activity. Conclusions Overweight children are not less physically active than normal-weight children, which may be associated with the risen awareness towards overweight/obesity and with implemented interventions for children with overweight/obesity.
Freshwater input and vertical mixing in the Canada Basin's seasonal halocline: 1975 vs 2006-2012

The Arctic seasonal halocline impacts the exchange of heat, energy, and nutrients between the surface and the deeper ocean, and it is changing in response to Arctic sea ice melt over the past several decades. Here, we assess seasonal halocline formation in 1975 and 2006-2012 by comparing daily, May to September, salinity profiles collected in the Canada Basin under sea ice. We evaluate differences between the two time periods using a one-dimensional (1D) bulk model to quantify differences in freshwater input and vertical mixing. The 1D metrics indicate that two separate factors contribute similarly to stronger stratification in 2006-2012 relative to 1975: (1) larger surface freshwater input and (2) less vertical mixing of that freshwater. The larger freshwater input is mainly important in August-September, consistent with a longer melt season in recent years. The reduced vertical mixing is mainly important from June until mid-August, when similar levels of freshwater input in 1975 and 2006-2012 are mixed over a different depth range, resulting in different stratification. These results imply that decadal changes to ice-ocean dynamics, in addition to freshwater input, significantly contribute to the stronger seasonal stratification in 2006-2012 relative to 1975. These findings highlight the need for near-surface process studies to elucidate the impact of lateral processes and ice-ocean momentum exchange on vertical mixing. Moreover, the results may provide insight for improving the representation of decadal changes to Arctic upper-ocean stratification in climate models that do not capture decadal changes to vertical mixing.
On-Road Air Quality and the Effect of Partial Recirculation on In-Cabin Air Quality for Vehicles

Author(s): Grady, Michael | Advisor(s): Jung, Heejung | Abstract: The California Air Resource Board (CARB) recently reported that due to exposure to particle emissions, 9,000 people die annually in California alone [11]. A method for quantifying the exposure during a daily commute as well as reducing the exposure for the passengers has been developed. A fractional recirculation of cabin air was proposed and studied to improve cabin air quality by reducing cabin particle concentrations. Vehicle tests were run with differing number of passengers (1, 2, 3, and 4), four fan speed settings and at 15, 40, and 70 mph. A manual control was installed for the recirculation flap door so different ratios of fresh air to recirculated air could be used. Full recirculation is the most efficient setting in terms of thermal management and particle concentration reduction, but this causes elevated CO2 levels in the cabin [5]. The study demonstrated cabin CO2 concentrations could be controlled below a target level of 2000ppm at various driving conditions and fan speeds with more than 85% of recirculation. Additionally, some energy saving is also expected with the air conditioning system. More recirculation means less energy is required to cool the cabin air, as opposed to cooling 100% outside air under hot weather conditions. The proposed fractional air recirculation method is a simple yet innovative way of improving cabin air quality.
CFD prediction of ship response to extreme winds and/or waves

The effects of winds and/or waves on ship motions, forces, moments, maneuverability and controllability are investigated with URANS computations. The air/water flow computations employ a semi-coupled approach in which water is not affected by air, but air is computed assuming the free surface as a moving immersed boundary. The exact potential solution of waves/wind problem is modified introducing a logarithmic blending in air, and imposed as boundary and initial conditions. The turbulent air flows over 2D water waves are studied to investigate the effects of waves on incoming wind flow. Ship airwake computations are performed with different wind speeds and directions for static drift and dynamic PMM in calm water, pitch and heave in regular waves, and 6DOF motions in irregular waves simulating hurricane CAMILLE. Ship airwake analyses show that the vortical structures evolve due to ship motions and affect the ship dynamics significantly. Strong hurricane head and following winds affect up to 28% the resistance and 7% the motions. Beam winds have most significant effects causing considerable roll motion and drift forces, affecting the controllability of the ship. A harmonic wave group single run seakeeping procedure is developed, validated and compared with regular wave and transient wave group procedures. The regular wave procedure requires multiple runs, whereas single run procedures obtain the RAOs for a range of frequencies at a fixed speed, assuming linear ship response. The transient wave group procedure provides continuous RAOs, while the harmonic wave group procedure obtains discrete transfer functions, but without focusing. Verification and validation studies are performed for transient wave group procedure. Validation is achieved at the average interval of 9.54 (%D). Comparisons of the procedures show that harmonic wave group is the most efficient, saving 75.8% on the computational cost compared to regular
Quality Assessment of Fruits and Vegetables using Bio-impedance based Expert System

World Health Organization (WHO) recommends a daily intake of at least 400 grams of fruits and vegetables, to prevent diet related chronic diseases and micronutrient deficiencies. It is essential to ensure the quality of foods consumed by the population on a daily basis. Quality of fruits and vegetables is governed by nutritional level, appearance, flavor and climate. Quality assessment methods should be environment friendly and should also benefit both consumers and farmers by enhancing taste and increasing yield, respectively. Conventionally employed quality assessment methods like bio-chemical analysis, imaging etc. are destructive, inefficient and time consuming. Bio-tissues are made up of cells with selectively permeable cell membranes and this makes them equivalent to resistive-capacitive network. Such a network impedes an alternating current (AC) excitation signal applied to it. This bio-impedance (BI) is measured through LCR meters, impedance analysers and off-the shelf chip based boards. In this work we have developed an accurate, smart and non destructive bio-impedance based quality evaluation technique. BI is measured as magnitude and phase for 7 days for each variety of fruit and vegetable followed by exhaustive frequency (5 kHz-200 kHz), ripening and rot analysis. BI magnitude increases as number of days advance i.e. with ripening and the phase undergoes considerable decrease with rotting. The system is made smart by incorporating an expert system. 178 samples of bio-impedance data are used to train the expert system and supervised classification is done through Random Forest classifier. Any fruit or vegetable can be classified as ’Good’ or ’Bad’ immediately and accurately with a maximum accuracy of 98.57%
Design Recommendations for Concrete Tunnel Linings : Volume I. Results of Model Tests and Analytical Parameter Studies.

This report describes model tests and analytical studies that were performed to augment background information based on experience, interviews with design engineers, and review of the literature to propose design recommendations for concrete tunnel linings. Tests of model arches that represent underground stations and circular linings that represent continuous tunnels in rock-like media are described. Ten arches, 6 ft (1.8m) diameter, were tested to investigate modes of failure and determine the effects of lining thickness, medium stiffness, lining stiffness, lining reinforcement, shear between the lining, and medium and active load shape. Tests are also described of five circular linings, 1.0 in. (25 mm) thick and 44 in. (1120 mm) diameter, in which the effects of lining reinforcement, medium stiffness, and joints in the lining are investigated. A computer based analysis is described that will simulate a concrete lining and include the nonlinear behavior due to material properties of the concrete and reinforcement and cracking of the concrete. In the analysis, the nonlinearity due to deformations can also be included. The medium around the lining can be represented by radial and tangential springs or by continuum elements, and in the latter case, a special interface element between the lining and medium may be used. This analysis was used to simulate the model tests to verify the program and the various input parameters, and then to investigate the various parameters that have a major influence on lining behavior and lining-medium interaction.
URANS And DES for Delft catamaran for static drift conditions in deep water

Understanding of three-dimensional separation around ships on straight course or under maneuvering is important for developing next generation ships with improved performance in extreme maneuvers. The separation causes vortex-dominated flows in which the vortex breakdowns at sufficiently high drift angles. The object of this study is to identify and analyze the vortical structures and instabilities around high-speed Delft catamaran and validate URANS and DES solver CFDShip-IowaV4 in collaboration with NATO AVT 183 (Reliable Prediction of Separated Flow Onset and Progression for Air and Sea Vehicles). The computations are performed at wide ranges of Froude numbers (Fr) and drift angels (B). The CFD results are compared to EFD data provided from different facilities including BSHC, INSEAN and Delft. The data included motions, integral variables, wave profile and SPIV measurements. Three sets of CFD simulations are performed: (1) hull free to heave and pitch with 0.3<Fr<0.77 and 0<B<30 with URANS, (2) hull fixed at dynamic heave and pitch conditions with Fr=0.4, 0.5 and B=6, 9 with DES, (3) hull fixed at even keel condition with Fr=0.5 and B=6 with DES, and (4) hull free to heave and pitch with Fr=0.3 and B=24 with URANS and DES. Hydrodynamic forces, moments and motions for B=0 are compared to the experimental results from different facilities. In general, good agreement between experiments conducted at the Delft and INSEAN facilities, and CFD are achieved at B=0 with forces and motions errors less than 13%D. Although there is a good agreement on the force between CFD and BSHC experiments, the motions show large error with more than 30%D for heave and pitch. The difference in the experimental results could be attributed to the difference in non-dimensional depth in the experiment. For 0<B<10, CFD results are compared to the BSHC experimental results. The error for forces (X, Y) and moment (N) are less than 10%D. However, the error for the motions is 28%D and 36%D for heave and pitch respectively. The flow field around the catamaran is analyzed, including detailed study on vortex structures and wave elevations. This information is used to design the grid for DES simulations for cases (2), (3), and (4). The local mean velocity components are compared to the SPIV results from the INSEAN facility. Verification study shows oscillatory convergence for X and Y while monotonic divergence for N. The mean errors of the local velocity components are all less than 5%D. Although the LES was activated in the vortex regions, the turbulence was not fully resolved. Also, the verification and validation studies of forces and moments on demihulls, motions and wave…
The Assessment of System Maintenance and Design Conditions on Railway Crossing Performance

A series of numerical simulation tools have been developed to predict the kinematic motion of a railway wheelset at a crossing and derive the dynamic vertical force occurring as a result of the wheel load transfer between the wing rail and the crossing nose. The tool has been used to show that for new crossing and a large representative range of worn wheels, the peak dynamic force is strongly influenced by the state of wear of the wheel and its lateral position (higher force occurs as the wheel moves towards flange contact on the crossing nose). Arguably, as the crossing wears to conform to the shape of the wheels travelling over it, this tendency may reduce over time. It is suggested that such a tool may be a powerful and fast way of optimising crossing geometry so that damage arising from dynamic impact loads are minimised at the early stage of a crossing life cycle. It may also be envisaged that a crossing may be optimised based on the type and age the traffic running on the specific line it is installed
Design for play: a guide to creating successful play spaces.

Aileen Shackell Aileen Shackell is a landscape architect with over 15 years' experience working in parks and open spaces, many of which have included play areas. She has worked in both the private sector and for the environmental charity Groundwork and now runs her own landscape practice. Nicola Butler is the Director of the Free Play Network, a network of individuals and organisations that aim to promote the need for better play opportunities for children. Phil Doyle has over 30 years' experience in the local authority and voluntary sectors developing play opportunities for children and young people in a wide range of settings. Phil has extensive experience of community engagement and involvement on public play spaces. He has practical experience of initiating and project managing the development and design of play spaces and has a real understanding of the maintenance implications of designed schemes. He was previously the local authority representative for the Local Government Association on the Play Safety Forum. David first became involved with child safety issues in 1986 when working at the Greater London Council. His interest in this subject has continued throughout, and has resulted in major publications on the topic, for example, Playgrounds – risks, benefits and choices, published by the Health and Safety Executive in 2002. David also has lengthy experience with risk issues in general including the legal process. Free Play Network The Free Play Network is a charity dedicated to improving children's opportunities for outdoor play. The Network has more information on designing for play, including innovative examples of play space design on its website at Play England Play England aims for all children and young people in England to have regular access and opportunity for free, inclusive, local play provision and play space. Play England provides advice and support to promote good practice, and works to ensure that the importance of play is recognised by policy makers, planners and the public. For further information visit CABE Space CABE is the Government's advisor on architecture, urban design and public space. CABE Space is the specialist unit that aims to bring excellence to the design, management and maintenance of parks and public space in our towns and cities. For more information, visit HSE commends the application of sensible health and safety management principles to the provision of children's play, and recognises the importance of enabling innovation and learning through recreational and learning activities …
Integrating Mobile Technology Quality Service, Trust and Cultural Factors Into Technology Acceptance of Mobile Learning: A Case of the Jordan Higher Education Institution

The success of mobile learning system in higher education depends a lot on the students‟ acceptance of the technology. From an early investigation, students at Jordanian higher educational institutions however are still unwilling to use mobile learning applications and services. The students‟ acceptance should be a key concern for the management of a university in considering the implementation of mobile learning system. The objective of this study is to identify the factors that influence the acceptance of mobile learning system based on the Technology Acceptance Model (TAM). A total of 500 questionnaires were distributed to five universities in Jordan, out of which 398 question-naires were returned, representing 79% response rate. Statistical techniques including bivariate correlation analyses, multiple linear and stepwise regression analyses, T-tests, and One-Way ANOVA were used. The results showed three core determinants: Culture, Trust, and Technology Service Quality as significantly influenced Perceived Usefulness and Perceived Ease of Use. Perceived Usefulness and Perceived Ease of Use moreover have significantly determined Attitude, while Perceived Usefulness and Attitude, have significantly determined users‟ Behavioral Intention. Among the five variables of culture, the study found Power Distance to be the most contributive variable, and Trust in University as the most contributive variable under the Trust factor. Meanwhile, the most contributive variable in Technology Service Quality factor is Accessibility. For the Demographic factors, the study proved that gender, mobile learning experience, and mobile internet experience have significantly influenced students‟ acceptance. Based on the results obtained, the study proposes a model of mobile learning acceptance based on TAM. A comprehensive understanding of this model will assist decision makers to enhance the acceptance of the mobile learning system among students in Jordanian higher educational institutions in the future.
The march in place activity – a view from the local concentration of red blood cells (CRBC) in the human foot dorsum

Sedentary habits are in the origin of microcirculation dysfunctions however simple tasks might act as active preventers. This study aims to evaluate potential changes in microcirculation by using subsurface polarisation light spectroscopy in human foot, while march in place. Eleven healthy volunteers (25.6 ± 5.4 years) of both sexes, normal ankle-brachial index (1.08 ± 0.15) participated in this study. The protocol consists of one minute in standing position (Phase 1); one minute of march in place (Phase 2), and one minute of recovery (Phase 3). The local CRBC was assessed by the Tissue Viability Imaging® System probe, detecting changes between Phase 1 and Phase 2 (p=0.016) but not for Phase 3 (p=0.113). Photoplethysmography (PPG) was also used, revealing significant changes in Phase 3 both for wave amplitude (p=0.016) and pulse rate (p=0.005). These findings can be explained as a physiological response to movement. Gender differences were found in Phases 2 and 3 (p=0.011 and p=0.006), with higher CRBC values in men. Simultaneously the gastrocnemius was evaluated using surface electromyography (sEMG) with significant increases observed in Phase 2 (p=0.003). Nevertheless, additional studies are needed to understand the behaviour of the microcirculation during physical activity.
Aeronautical Design Standard Performance Specification Handling Qualities Requirements For Military Rotorcraft

Abstract : This specification contains the requirements for the flying and ground handling qualities of rotorcraft. It is intended that the specification should cover land based rotorcraft which have primary missions ranging from scout and attack to utility and cargo. Additional requirements or modified standards may be required for rotorcraft that have to operate from small ships in sea states resulting in more than small ship motion. Intended use is described in 6.1. The requirements of this specification are intended to assure that no limitations on flight safety or on the capability to perform intended missions will result from deficiencies in flying qualities. Flying qualities for the rotorcraft shall be in accordance with the provisions of this specification unless specific deviations are authorized by the Government. Additional or alternate special requirements may be specified by the procuring activity. For example, if the form of a requirement should not fit a particular vehicle configuration or control mechanization, the Government may, at its discretion, agree to a modified requirement that will maintain an equivalent degree of acceptability.
Josephson Parametric Amplification for Circuit Quantum Electrodynamics: Theory and Implementation

Abstract : Circuit Quantum Electrodynamics (cQED) is a highly promising platform for quantum control, quantum simulation, and quantum optics in a solid-state environment. Such systems consist of arti cial atoms coupled to superconducting resonators, and can be probed with microwave signals on a chip. This thesis theoretically and experimentally studies a method of quantum-limited Josephson parametric ampli cation for the improvement of such microwave measurements. A theoretical analysis of parametric ampli cation with a nonlinear quantum oscillator is given, along with an analysis of a particular implementation with a superconducting coplanar waveguide resonator shunted by an array of SQUIDs. A parametric ampli er chip is designed and a fabrication process is engineered. Measurements and analysis of a successfully fabricated device are presented, and future outlook is discussed.