Miracle-dz/UniFAR-FTUs huggingface dataset:
Influence of load shedding in the voltage stability of an electric power system using trajectory sensitivity analysis

Trajectory sensitivity analysis can provide valuable insights into the security of an electric power system. There is a strong correlation relating the system stability and the corresponding trajectory sensitivity. In this paper it is analyzed the influence of load shedding in the voltage stability of an electric power system using trajectory sensitivity analysis. It is recognized that voltage instability and collapse have led to major system failures. The emergency load shedding is one of the most important methods to preserve the system stability. In this study different values of load shedding were used to avoid voltage collapse. The automatic voltage regulators of the generating units and the turbine speed governors were modelled. Different load models were used and the under load tap changers were also taken into account. The simulation results were obtained using EUROSTAG program and post-processing module developed using the Matlab software package.
Structural equation models suggest that bottom‐up processes override top‐down processes in boreal pikeperch (
 Sander lucioperca
 ) lakes

Inter‐relations between water quality and piscivore populations have remained poorly studied but their quantification is crucial for the ecosystem‐based management of inland waters. Here, we aimed to estimate the relative strength of bottom‐up and top‐down trophic interactions between water quality and fish community composition using a comparative approach. Our main hypothesis was that lakes with an abundant piscivore (mainly pikeperch, Sander lucioperca, Percidae) stock would have better water quality than similar lakes with a poor piscivore stock. We used structural equation models on biomass catch per unit of effort data from standard gillnet test fishing to examine the effects of predators (pikeperch, pike [Esox lucius, Esocidae] and piscivorous perch [Perca fluviatilis, Percidae]) on cyprinids (Cyprinidae), and the effects of cyprinids, nutrients, and lake depth on water quality measured as chlorophyll‐a concentration and turbidity. We derived the dataset covering a single summer snapshot of 138 Finnish pikeperch lakes from national databases. Nutrients and lake depth index, the main principal component describing positive effects of nutrient concentrations and negative effects of lake depth, had a positive effect on chlorophyll‐a concentration and turbidity. Pikeperch had a detectable negative effect on both planktivorous and benthivorous cyprinids. While pike also had a negative effect on benthivorous cyprinids, both groups of cyprinids had a positive effect on pikeperch and pike. Supporting the strong, fish‐independent bottom‐up regulation, no significant relationships were detected between the cyprinids and water quality. This study suggests that the bottom‐up effects override the top‐down effects, and despite pikeperch is an efficient piscivore, the observed stock levels did not cascade down to improved water quality. Thus, in lake restoration, reductions of nutrient loading appear more efficient than biomanipulation aimed to strengthen the top‐down links.
An acoustic navigation system

Prepared for the Office of Naval Research under Contracts N00014-71-C0284; NR 293-008 N00014-70-C0205; NR 263-103 and the National Science Foundation/International Decade of Ocean Exploration Grant GX-36024 and the Applied Physics Laboratory of The Johns Hopkins University Contract 372111.
A wafer-level liquid cavity integrated amperometric gas sensor with ppb-level nitric oxide gas sensitivity

A miniaturized amperometric nitric oxide (NO) gas sensor based on wafer-level fabrication of electrodes and a liquid electrolyte chamber is reported in this paper. The sensor is able to detect NO gas concentrations of the order of parts per billion (ppb) levels and has a measured sensitivity of 0.04 nA ppb−1 with a response time of approximately 12 s. A sufficiently high selectivity of the sensor to interfering gases such as carbon monoxide (CO) and to ammonia (NH3) makes it potentially relevant for monitoring of asthma. In addition, the sensor was characterized for electrolyte evaporation which indicated a sensor operation lifetime allowing approximately 200 measurements.
Evaluation of the Fish Passage Effectiveness of the Bonneville I Prototype Surface Collector using Three-Dimensional Ultrasonic Fish Tracking

This report describes tests conducted at Bonneville Dam on the Columbia River in the spring of 2000 using three-dimensional acoustic telemetry and computational fluid dynamics hydraulic modeling to observe the response of outmigrating juvenile steelhead and yearling chinook to a prototype surface collector installed at the Powerhouse. The study described in this report was one of several conducted for the U.S. Army Corps of Engineers to prepare a decision document on which of two bypass methods: surface flow bypass or extended-length submersible bar screens to use to help smolts pass around Bonneville dams without going through the turbines.
Developing healthcare non-technical skills training through educational innovation and synthesis of educational research

This thesis presents a programme of nine key published works, as well as twelve published supporting works focusing on two areas. Firstly, an investigation of how non-technical skills education in healthcare can be used to enhance outcomes for patients. Secondly, an exploration of how evidence synthesis be used as a tool to direct educational innovation and, in this context, enhance patient safety. Non-technical skills are the interpersonal, communication, team working and decision making skills that support safe patient care. Existing theory was applied to build new conceptual frameworks to understand how non-technical skill learning occurs. Educational innovations were developed, allowing outcomes for patients to be enhanced and the theory to be refined. Ultimately, this has led to the proposal of the SECTORS model, combining three key elements: The generic knowledge and skills in core areas that contribute to and support learning in non-technical skills (Systems and technology use, Error awareness, Communication, Team working), a situated cognition approach to formal and experiential learning that develops these skills (Observation and simulation) and developments in analytical skills that can integrate these and support decision making (Risk assessment and situational awareness). SECTORS can support curricula design, educational innovation and design of assessments. SECTORS will support future scholarly research, allowing the field to move from theory generation to theory testing and refinement. Additionally, synthesis of educational evidence to support the development of this new knowledge has been employed. Building on existing guidance and in response to calls for more theoretical generation in primary educational research, a complete method for health education evidence synthesis has been developed and applied. This method allows clarification of educational questions through generation of conceptual frameworks and new theory within a systematic framework that employs qualitative synthesis techniques such as thematic generation and meta-ethnography, representing a significant contribution to the field.
The Influence of Antiphase Crosstalk on the Localization Cues in Stereo Signals

Widening of the stereo base is an attractive feature for stereo sets with closely spaced loudspeakers. This effect is brought about by the introduction of crosstalk in antiphase between the two stereo channels. An analysis of this phenomenon must be based on the directional localization cues of human hearing. The most important cues are lnteraural differences of level, phase delay and group delay. We show that the localization directly in front of the loudspeakers is determined by the interaural time delay differences only; to either side of thi_ position interaural level differences play a part too. At some positions, however, level effects and time delay effects provide conflicting localization cues, leading to a rather vague image of a virtual 8ource. Listening experiments were carried out to verify these results. From this investigation it follows that the introduction of a small time delay in the crosstalk circuit shifts the regions with reinforcing localization cues in the direction of the listener, thus improving the localization of virtual sources in the widened stereo image. 1.INTRODUCTION Stereo sound reproduction from two loudspeakers in a standard stereo set-up may create virtual sources at every position between the loudspeakers, i.e. the stereo base. Lauridsen and Sehlegel [1] found a way to widen the stereo base beyond two closely spaced loudspeakers. They use an arrangement that allows for crosstalk in antiphase between the two stereo channels. Hanson and Kook [2] state that at equal distances from two loudspeakers radiating in antiphase the intensity must show a minimum. By means of a phasor model Bauer [3] shows that signals in antiphase from two loudspeakers produce a phase difference between both ears of a listener positioned in the middle. Tappan [4]
Data Routing Protocol Using TDMA for a Wireless Sensor Network with Structured Topology for a Noisy Environment

Wireless sensor networks enable the development and implementation of a wide range of applications related to home automation, environmental, safety, health, industrial environments and monitoring. However, there are still some application areas that have not been addressed efficiently, such as wireless sensor networks capable of operating in noisy environments. These operating conditions adversely affect the latency of the links, in the use of energy resources and the processing capacity of the sensor, among others. This research presents a wireless sensor network that can operate efficiently under noisy environments. This was achieved by designing an access medium protocol, based on Time Division Multiple Access (TDMA), and a packet routing protocol, wich is not dependent on the acknowledgment messages, to reduce the effects of noise in the communication proccess. The simulation results show that it is possible to guarantee a maximum time for delivery of packets transmitted from the sensor nodes to the base station.
Monitoring and Control of Risks Associated with Food Production and Food Handling: the HACCP System and its Application to the Food Businesses with Particular Regard to Cyprus

A harmonised approach to food safety across the EU, including the Accession States, is essential to meet growing public concerns. For the Cyprus economy dependant on tourism, high confidence in the safety of its food is vital. The emphasis in the present research has been on factors that influence the implementation of food safety procedures in Cyprus. The investigation has concentrated on a particular approach to ensuring food safety known as HACCP. There has been no previous research on this topic in Cyprus. The principal methodology was the application of specifically designed questionnaires combined with personal interviews and literature based evaluations. Seven percent of the total food businesses in Cyprus were surveyed. Very unusually for studies of this nature the participation rate was approaching 100%. The key factors for implementation of the HACCP system in Cyprus that have been identified in this survey are as follows: 0 The degree of understanding of food safety and of the HACCP system by each food business. The level of education was inversely correlated with the number of mistakes the respondents made in identifying the most important hazards, 0 The commitment of businesses and the resources available to implement food safety measures. The size of the business was shown to correlate directly with their implementation of the HACCP system and 0 The ability to gain access to appropriate expertise. This was a major problem, particularly, for small businesses. The results were compared with those of a study conducted in Crete. The similarity of the results indicated that legislation was not a key factor for the HACCP system implementation.
MEASURING BENEFITS OF THE SOUTH EAST BUSWAY: TOWARDS A NEW APPROACH FOR VALUING PUBLIC TRANSPORT PROJECTS

The much heralded South East Busway is a flagship public transport project for Brisbane and was the first busway delivered as part of Brisbane‟s busway strategy; which is now coming to fruition with parts of the northern and eastern busway under construction. Less than 10 years after it was constructed, parts of the South East Busway are close to full capacity, with people cramming into buses and buses cramming into busway stations. Why then, with its apparent success, is it still so difficult to prove the benefits of busway projects (and other public transport projects)? This paper looks at the first comprehensive evaluation of the South East Busway since it opened in 2001. This included the first comprehensive passenger and bus survey completed since the South East Busway opened. Using the results of this survey, and blending it with a range of other data sources, alternative methods for quantifying the benefits of busways and potentially other public transport projects are presented. Key conclusions are then drawn regarding how the findings can be used to establish support for future busway projects, as well as ways to build on this evaluation to assist in establishing more robust business cases for future projects.
Kinesthetic coupling between operator and remote manipulator

A universal force-reflecting hand controller has been developed which allows the establishment of a kinesthetic coupling between the operator and a remote manipulator. The six-degree-of-freedom controller was designed to generate forces and torques on its three positional and three rotational axes in order to permit the operator to accurately feel the forces encountered by the manipulator and be as transparent to operate as possible. The universal controller has been used in an application involving a six-degree-of-freedom mechanical arm equipped with a six-dimensional force-torque sensor at its base. In this application, the hand controller acts as a position control input device to the arm, while forces and torques sensed at the base of the mechanical hand back drive the hand controller. The positional control relation and the back driving of the controller according to inputs experienced by the force-torque sensor are established through complex mathematical transformations performed by a minicomputer. The hand controller is intended as a development tool for investigating force-reflecting master-slave manipulator control technology.
Compact UWB bandpass filter with two notched bands based on electromagnetic bandgap structures

A novel and compact ultra-wideband (UWB) bandpass filter with dual narrow notched bands based on two mushroom-type electromagnetic bandgap (EBG) structures is presented. The UWB BPF comprises two coupled lines which are coupled to the open-ended coplanar waveguide on the ground and two EBG structures near the feedline. By simply adjusting the dimensions of the two EBG structures, the centre frequencies of the notched bands can be allocated at 5.2 and 5.8 GHz, respectively. The UWB bandpass filter has been simulated, fabricated and measured, with good agreement between the simulated and measured results. The two notched bands of the BPF centred at 5.2 and 5.8 GHz have 10 dB fractional bandwidths of about 5.7 and 3.4 , respectively.
Teacher's Perception on Transformational Leadership Based on Primary Schools in Peninsular Malaysia

Educational organizations have witnesses a rapid change since the last decade with effort to increase effectiveness. Like many other countries, Malaysian education system also faced tremendous changes and transformation. The Malaysia Education Blueprint 2013-2025 was implemented in accordance to bring positive and sustainable transformation to the Malaysian education system. The fifth shift of the reformation highlights the need of ensuring high-performing schools leaders in schools (Ministry of Education, 2013). As such, in line with current reformation and transformation in the Malaysian education context, the transformational leadership received the most attention as an ideal leadership in bring about the changes into schools (Khalip Musa, 2013). Moreover, this leadership style has gained support in the literature and has been recommended as an appropriate model of school leadership especially to schools that faces 21 st century challenges (Nir & Hameiri, 2013; Talebloo et al., 2015; Leithwood & Jantzi, 2006). According to Jamilah Man et al. (2016), in order to be in line with current National Educational Blueprint (2013-2025), a leader should practice all the dimensions of transformational leadership at its best.
Design of RF Oscillators for Wireless Digital Transmitters

Cost reduction is one of the main driving forces for integration. As such, advanced CMOS technologies offer excellent digital functionality and high-density integration capabilities. Properties that persuade designers to exploit new digitally assisted approaches rather than following conventional analogue techniques. Using these new concepts, fully integrated transmitters that operate from baseband up to the pre-power amplifier (PA) stage entirely in the digital domain have become feasible. However, this imposes many coupling issues for different parts of the transceiver, such as the local oscillator. One of the primary building blocks of the transmitter is an oscillator and each modern digital transmitter has to have at least one oscillator, which normally has tough specifications imposed by the standard and transceiver architecture. This thesis focuses on the design of digitally controlled oscillators which could have excellent phase noise, very fine frequency resolution, small footprint and wide tuning range. Moreover, a simple yet an efficient architectural solution for the problem of local oscillator pulling, which will likely be the main cause degrading spectral purity of the TX output in multi radio SoCs has been proposed.
Wafer bonding : mechanics-based models and experiments

Direct wafer bonding has emerged as an important technology in the manufacture of silicon-oninsulator substrates (SOI), microelectromechanical systems (MEMS), and three-dimensional integrated circuits (3D IC’s). While the process is currently employed in applications such as these, a lack of knowledge of the basic mechanics of the process has made developing robust processes and preventing process failures extremely challenging. The current work addresses this problem through the development and validation of mechanics-based models that connect the wafer geometry, etch pattern, clamping configuration, and work of adhesion to bonding failure. An energy-based bonding criterion, which allows the effect of flatness variations and etch patterns to be quantified, is presented and employed to develop analytical and numerical models. Analytical models, based on plate theory, are developed to examine the role of wafer-scale shape variations, etch patterns, and the clamping configuration. Finite element models are developed to verify the analytical models and to evaluate the bonding criterion for wafers with anisotropic elastic properties and arbitrary geometries. Experiments in which silicon substrates with wafer-scale shape variations and etch patterns were bonded demonstrate that the shape and size of the bonded area and the shape of the bonded pair can be predicted using the models developed. The effect of mid-spatial wavelength height variations (nanotopography) on bonding is examined through a combination of modeling and experiments. The experiments and analysis provide a route for characterizing nanotopography and assessing its impact on bonding. The accuracy of the wafer bonded double cantilever beam, which is one method to evaluate the key process parameter of interface toughness, is also examined in the current work. The results of the modeling and experiments are discussed to provide guidance in process, device, and tool design. The models that are presented may be used to establish tolerances on wafer geometry and to improve process control. Thesis Supervisor: S. Mark Spearing Title: Associate Professor of Aeronautics and Astronautics
Fine grained software rejuvenation models

Preventive maintenance of operational software systems is a technique used to counteract the phenomenon of software "aging". Haung et al. (1995) proposed a technique called "software rejuvenation" in which the software is periodically stopped and then restarted in a "robust" state after a proper maintenance. This "renewal" of the software prevents, or at least postpones, the occurrence of crash failures. Previous models of software rejuvenation were all based on a "black box" approach in which the degradation mechanism was modeled by three stares: a fully available state, a degraded state from which the decision whether to rejuvenate can be taken, and a crash state. The present paper proposes a fine grained model for the quantitative analysis of software rejuvenation. The model is based on the assumption that it is possible to identify the current degradation level of the system by monitoring an observable quantity, so that the future strategy can be tuned on the measured parameter. Two different strategies are discussed to decide whether and when to rejuvenate. Furthermore, resorting to the theory of renewal processes with reward the steady-state unavailability can be estimated for the various policies and an optimality criterion can be invoked to evaluate the proper rejuvenation intervals. A set of numerical experiments conclude the paper.
Essays on capacity utilization, vehicle choice, and networks in the trucking industry

In recent years there has been a growing interest to understand the drivers and the limits of road freight demand in many countries. Behind this interest lies a strong desire to improve operational performance in road freight transport, which has remained stable for many years. A recent report for 13 European countries reveals that on about 30 per cent of all trips made the trucks are empty, while the percentage of a truck’s carrying capacity filled with a cargo (that is, the load factor) remained stable at an average of 50 percent over the period 1990-2008 (European Environmental Agency, 2010). The overall objective of this PhD thesis is to provide economic analyses of some of the drivers and limits of road freight transport, and their implication on the trucking industry’s performance. It is composed of four self-contained chapters which can be read independently. Each chapter addresses this objective from various angles to provide economic perspectives and policy recommendations. Chapter 1 sets the stage by reviewing studies on capacity utilization in road freight transport from the economics and engineering literature. It draws important lessons and sheds light on potential gains that can be achieved by combining the two strands of studies. Chapter 2 looks at two aspects of capacity utilization, namely the extent of empty running and the load factor. It shows that they are explained as a function of truck, haul and carrier characteristics. Chapter 3 analyzes how firms choose the optimal truck size and shipment size. Chapter 4 looks at the effect of fuel price on the operating characteristics of the trucking industry.