Miracle-dz/UniFAR-FTUs huggingface dataset:
Micro RF Ion Engine for Small Satellite Applications

A xenon-fueled, micro rf ion engine suitable for small satellite propulsion was developed by Busek. Operating with a pair of grids that are 3 cm in diameter, the thruster demonstrates 1.4-2.1 mN thrust and 1500-2850 seconds Isp. Total power consumption ranges from 60 to 100 W. At the optimum Isp of 2500 seconds, the estimated thrust efficiency and propellant utilization is 49% and 47%, respectively. Total efficiency, including 90% dc-to-rf conversion, is estimated at 21%. The total efficiency can potentially be increased up to 27% by reducing rf coupling loss. Busek is dedicated to further miniaturize rf ion engines with the development of a 1-cm thruster equipped with a propellant-less carbon nanotube field emission neutralizer. Projected performance of the 1-cm micro rf ion engine is 0.15 mN thrust, 1570 seconds Isp and 14 W total power consumption.
Challenges to STS Education: Implications for Science Teacher Education

As future citizens, students must make decisions requiring an understanding of the interaction of science and technology and its interface with society. STS education has been strongly identified with meeting this goal, but putting theory into practice has so far been difficult. This article asks, “What are the challenges influencing science teachers to implement STS education in the science classroom? ” The author investigated using a mixed method research technique incorporating multiple sources of qualitative and quantitative data (questionnaire, interviews, field notes, and classroom observations). Constraints a fecting teachers' practices in teaching science through STS education were identified and can be categorized into impersonal, interpersonal, and personal constraints. Findings indicated interactions within and between external and internal constraints. Suggestions are made for implementing change in various aspects of science teacher education.
Electronic Banking Channels as a Strategy for Gaining Competitive Advantage in Banking Services: A Case of Kenya Commercial Bank

v ACKNOWLEDGEMENT . viii DEDICATION. ix TABLE OF CONTENTS . x LIST OF TABLES . xiii LIST OF FIGURES . xiv LIST OF ACRONYMS . xv CHAPTER ONE . 1 1.0 INTRODUCTION. 1 1.1 Background of the Study . 1 1.2 Statement of the Problem . 7 1.3 General Objective . 9 1.4 Specific Objectives . 9 1.5 Importance of the Study . 9 1.6 Scope of Study . 10 1.7 Definition of Terms. 10 1.8 Chapter Summary . 11 CHAPTER TWO . 13 2.0 LITERATURE REVIEW . 13 2.
Deteriorating Weather Conditions Predict the use of Suboptimal Stopover Sites by Aquatic Warblers Acrocephalus paludicola

Abstract. The Aquatic Warbler Acrocephalus paludicola is a globally threatened songbird and its decline is related to habitat loss. Accordingly, most studies dealing with the stopover ecology of this species have been chiefly focused on the habitat use and the availability of suitable habitats along its route of migration. In contrast, much less attention has been paid to other environmental causes potentially explaining the use of stopover sites. Our aim here was to investigate whether the Aquatic Warbler at an apparently suboptimal stopover site with small area of suitable habitats stops over only during adverse weather conditions. We used data obtained at a suboptimal (Jaizubia marshland, northern Iberia) and another optimal (Villefranque, southwestern France) stopover sites during the autumn migration over four seasons (2007–2010). The Aquatic Warbler tended to stop over at Jaizubia in days with rain, a fact that was not so evident at Villefranque, supporting the hypothesis that they used the suboptimal site only, or mostly, when adverse weather conditions forced them to land. In contrast, the optimal habitat was used independently of weather conditions. To properly identify key stopover localities for the Aquatic Warbler, we should consider the potential influence of adverse weather in occurrence of individuals, especially in small areas without preferred habitat.
Student Learning Strategies in Mechanical Engineering Design

The study reports findings from administration of the Biggs SPQ instrument to two cohorts of students (1993 and 2004) enrolled in a mechanical engineering design course. A substantial decrease in 'surface' approaches to study was found in 2004, but there was virtually no change in the 'deep' approach scores. Findings are discussed in relation to changes made to teaching and learning context over this time, and to the suitability of the SPQ instrument.
Multispecies fisheries management in the Mediterranean Sea: application of the Fcube methodology

The ecosystem approach (EA) advocates that advice should be given based on a holistic management of the entire marine ecosystem and all fisheries and fleets involved. Recent developments have advanced to multiâspecies, multiâfisheries advice, rather than on a singleâspecies/fleet/area stock basis, bridging the gap between existing singleâspecies approaches and the needs of the EA. The Fleet and Fisheries Forecast method (Fcube) method estimates potential levels of effort by fleet in mixed fisheries situations to achieve specific targets of fishing mortality. Data on effort, landings and socioeconomic parameters were used for coastal and trawl fisheries in the Aegean Sea. Results pointed out the strengths and weaknesses of alternative management strategies from both a biological and socioeconomic perspective. Fcube revealed the importance of effort control in the coastal fisheries that are still managed with no effort restrictions. The present findings, although preliminary, revealed that stringent cuts to effort and catch levels are required if EA management goals are to be met. The Fcube methodology, initially developed for mixed fisheries advice in northern European waters that are managed with TACs, also proved promising in providing advice to nonâTAC fisheries.
Demographic assessment of a stocking experiment in European Eels

Since the 1980s, the European eels' stocks have dramatically decreased with no sign of recovery, resulting in their classification as Critically endangered on the IUCN red list of threatened species. The European Council Regulation 1100/2007 requires that 35% of glass eels caught annually by fishing be released in European waters for restocking. However, the efficiency of this measure on population viability has never been evaluated. Here, we estimated demographic parameters of a stocked population of French eels using a multistate capture- recapture model. Using these estimates, we then estimated population size and predicted the number of future genitors obtained by stocking. We found that the stage in which eels were stocked did not influence their future survival and that the maximal number of silver eels was quickly reached, after 3 years following stocking. We concluded that stocking experiments in the Mediterranean region are efficient for fast production of genitors. We suggest that further studies should assess the quality of these genitors.
Dynamics of interplate domain in subduction zones: influence of rheological parameters and subducting plate age

Abstract. The properties of the subduction interplate domain are likely to affect not only the seismogenic potential of the subduction area but also the overall subduction process, as it influences its viability. Numerical simulations are performed to model the long-term equilibrium state of the subduction interplate when the diving lithosphere interacts with both the overriding plate and the surrounding convective mantle. The thermomechanical model combines a non-Newtonian viscous rheology and a pseudo-brittle rheology. Rock strength here depends on depth, temperature and stress, for both oceanic crust and mantle rocks. I study the evolution through time of, on one hand, the brittle-ductile transition (BDT) depth, zBDT, and, on the other hand, of the kinematic decoupling depth, zdec, simulated along the subduction interplate. The results show that both a high friction and a low ductile strength at the asthenospheric wedge tip shallow zBDT. The influence of the weak material activation energy is of second order but not negligible. zBDT becomes dependent on the ductile strength increase with depth (activation volume) if the BDT occurs at the interplate decoupling depth. Regarding the interplate decoupling depth, it is shallowed (1) significantly if mantle viscosity at asthenospheric wedge tip is low, (2) if the difference in mantle and interplate activation energy is weak, and (3) if the activation volume is increased. Very low friction coefficients and/or low asthenospheric viscosities promote zBDT = zdec. I then present how the subducting lithosphere age affects the brittle-ductile transition depth and the kinematic decoupling depth in this model. Simulations show that a rheological model in which the respective activation energies of mantle and interplate material are too close hinders the mechanical decoupling at the down-dip extent of the interplate, and eventually jams the subduction process during incipient subduction of a young (20-Myr-old) and soft lithosphere under a thick upper plate. Finally, both the BDT depth and the decoupling depth are a function of the subducting plate age, but are not influenced in the same fashion: cool and old subducting plates deepen the BDT but shallow the interplate decoupling depth. Even if BDT and kinematic decoupling are intrinsically related to different mechanisms of deformation, this work shows that they are able to interact closely. Comparison between modelling results and observations suggests a minimum friction coefficient of 0.045 for the interplate plane, even 0.069 in some cases, to model realistic BDT depths. The modelled zdec is a bit deeper than suggested by geophysical observations. Eventually, the better way to improve the adjustment to observations may rely on a moderate to strong asthenosphere viscosity reduction in the metasomatised mantle wedge.
Evaluating the impact of the enhanced Street Broadcast Reduction scheme using real maps in VANETs

In traffic safety applications forVehicular ad hoc networks (VANETs), some warning messages have to be urgently disseminated in order to increase the number of vehicles receiving the traffic warning information. In those cases, redundancy, contention, and packet collisions due to simultaneous forwarding (usually known as the broadcast storm problem) are prone to occur. In the past, several approaches have been proposed to solve the broadcast storm problem in multi-hop wireless networks such as Mobile ad hoc Networks (MANETs). Among them we can find counter-based, distance-based, location-based, cluster-based, and probabilistic schemes, which have been mainly tested in non-realistic simulation environments. In this paper, we present the enhanced Street Broadcast Reduction (eSBR), a novel scheme specially designed to increase the percentage of informed vehicles and reduce the notification time; at the same time, it mitigates the broadcast storm problem in real urban scenarios. We evaluate the impact that our scheme has on performance when applied to VANET scenarios based on real city maps, and the results show that it outperforms previous schemes in all situations.
Interaction between turbulence and neoclassical effects in global gyrokinetic simulations

Introduction The steep radial gradients of the temperature and the pressure cause a tokamak plasma to be in a state of turbulence and this phenomenon provides the dominant channel for the transport of particles, heat and momentum. Collisions and the toroidal geometry of the magnetic guide field, however, provide an additional channel, neoclassical transport, which can become relevant if the turbulence becomes weak or suppressed[1]. While both neoclassical and turbulent transport have been studied extensively and mainly separately in the last decades, their possible interactions leave a number of open questions. In particular, regions with steep gradients such as transport barriers may enable synergies between the two as the separation of the ion gyroradius scale and the gradient length scale does not hold there.
COMPARISON OF THREE DNA ISOLATION AND PURIFICATION METHODS OF BACTERIAL DNA

The objective of this study was to compare the efficiency of three methods of nucleic acids extraction from gram-positive bacteria by evaluating the quantity and purity of DNA extracts. Nucleic acids extraction of gram-positive bacteria is normally hampered by a thick and resistant cell wall. Gram positive bacteria usually have a thick cell wall consisting mainly of many layers of peptidoglycan, which is not easily destroyed. This paper compares the different procedures based on mechanical and enzymatic cell breakage to extract DNA from Rhodoccocus pyridinivorans using GES method, Ultraclean Microbial DNA isolation Kit, and Prepman Microbial DNA isolation kit. DNA extracts were analyzed by agarose gel electrophoresis and UV spectroscopy. Yield and quality of DNA obtained by the GES method were higher than the other methods. Nucleic acids extracts with the highest yield and purity were amplified by Polymerase Chain Reaction (PCR) using various primers targeted on gene encoding nitrilase gene such as BLITF and PNITR, a NH1 and a NH2, s NH1 and s NH2, Amd1 and Amd 2. The gene encoding for nitrilase were amplified which was confirmed by sequencing analyses. However, the targeted gene length from the primes was not obtained. Therefore further amplification optimization may be needed. Keywords : extraction, DNA isolation Rhodococcus pyridinovorans, nitrilase gene
Influence of mass contrast in alloy phonon scattering

We have investigated the effect of mass contrast on alloy phonon scattering in mass-substituted Lennard-Jones crystals. By calculating the mass-difference phonon scattering rate using a modal analysis method based on molecular dynamics, we have identified the applicability and limits of the widely used mass-difference perturbation model in terms of the magnitude and sign of the mass difference. The result of a phonon-mode-dependent analysis reveals that the critical phonon frequency, above which the mass-difference perturbation theory fails, decreases with increasing magnitude of the mass difference independently of its sign. This gives rise to a critical mass contrast, above which the mass-difference perturbation model noticeably underestimates the lattice thermal conductivity.
Enhancement of Handwritings on Selected Charred Documents using Video Spectral Comparator (VSC)

Questioned documents are documents whose authenticity is disputed. Documents are destroyed by fires and other means to conceal criminal activities. Charred or burnt documents are a type of questioned document that are likely to contain vital information. These documents are mainly linked to ransoms, forgery, fraud, suicide and other white collar offences. This study aimed to evaluate the ability of a Video Spectral Comparator (VSC-6000) for the enhancement of writings on charred documents and to determine the effectiveness of flood light and white spot beam in VSC on charred documents. A passage was written by different types of writing instruments on different types of writing paper available in Malaysia. Then the handwritten documents were burned until the writings became invisible. The charred documents were viewed under flood light and the white beam by adjusting the wavelengths. Results showed that the writings on the charred document exhibited appreciable enhancement suitable for forensic investigation. The writings were comparatively more visible under the white spot beam than the flood light beam. These findings were recorded through photography. The present study provides a promising method and an effective alternative way to enhance writings on charred documents.
Simulation Study of Squirrel Cage Induction Generator Fed by a Back-to- Back Converter and by using a LCL filter

Nowadays the wind energy systems are widely used for power generation. In this book chapter are developed the rotorflux-oriented for torque and flux control of the squirrel cage induction generator (SCIG), and the grid-voltage-oriented for DC bus voltage and reactive power control of the grid using a LCL filter. Both the currents controllers for the generator and for the grid are implemented using proportional-integral (PI) current controllers in the d-q frame. In order to determine the stator currents references, the errors signal of torque and rotor flux are regulated by PI controllers with respect to the generator. On grid side converter the errors signal of DC bus voltage and reactive power are also regulated by means of PI controllers. The design of LCL filter is also presented. The control strategies employed in the grid and generator side converters and the LCL filter are evaluated by simulation for several speed operation of wind energy conversion system
A high‐resolution simulation of convective roll clouds during a cold‐air outbreak

A ubiquitous feature of the high latitude ocean is the occurrence of convective clouds that are organized into two‐dimensional structures known as roll clouds or cloud streets. In this paper, we present a simulation of these structures that was performed in a domain large enough to simulate numerous roll clouds and their downstream evolution at a resolution sufficient to resolve the individual convective clouds. The simulations were initialized and validated using observations of roll clouds over the Labrador Sea. The model results indicate that the secondary flow associated with the roll clouds results in significant differences in the temperature, humidity and momentum fields between the updrafts and downdrafts. The model was also able to reproduce the observed downstream evolution of the clouds as the organization of the convection changed from two‐dimensional rolls to three‐dimensional closed cells.
The SPAtial EFficiency metric (SPAEF): multiple-component evaluation of spatial patterns for optimization of hydrological models

Abstract. The process of model evaluation is not only an integral part of model development and calibration but also of paramount importance when communicating modelling results to the scientific community and stakeholders. The modelling community has a large and well-tested toolbox of metrics to evaluate temporal model performance. In contrast, spatial performance evaluation does not correspond to the grand availability of spatial observations readily available and to the sophisticate model codes simulating the spatial variability of complex hydrological processes. This study makes a contribution towards advancing spatial-pattern-oriented model calibration by rigorously testing a multiple-component performance metric. The promoted SPAtial EFficiency (SPAEF) metric reflects three equally weighted components: correlation, coefficient of variation and histogram overlap. This multiple-component approach is found to be advantageous in order to achieve the complex task of comparing spatial patterns. SPAEF, its three components individually and two alternative spatial performance metrics, i.e. connectivity analysis and fractions skill score, are applied in a spatial-pattern-oriented model calibration of a catchment model in Denmark. Results suggest the importance of multiple-component metrics because stand-alone metrics tend to fail to provide holistic pattern information. The three SPAEF components are found to be independent, which allows them to complement each other in a meaningful way. In order to optimally exploit spatial observations made available by remote sensing platforms, this study suggests applying bias insensitive metrics which further allow for a comparison of variables which are related but may differ in unit. This study applies SPAEF in the hydrological context using the mesoscale Hydrologic Model (mHM; version 5.8), but we see great potential across disciplines related to spatially distributed earth system modelling.
Both native and non-native disfluencies trigger listeners' attention

Disfluencies (such as uh and uhm) are a common phenomenon in spontaneous speech. Rather than filtering these hesitations from the incoming speech signal, listeners are sensitive to disfluency and have been shown to actually use disfluencies for speech comprehension. For instance, disfluencies have been found to have beneficial effects on listeners’ memory. Accumulating evidence indicates that attentional mechanisms underlie this disfluency effect: upon encountering disfluency, listeners raise their attention to the incoming speech signal. The experiments reported here investigated whether these beneficial effects of disfluency also hold when listening to a non-native speaker. Recent studies on the perception of non-native disfluency suggest that disfluency effects on prediction are attenuated when listening to a non-native speaker. This attenuation may be a result of listeners being familiar with the frequent and more variant incidence of disfluencies in non-native speech. If listeners also modulate the beneficial effect of disfluency on memory when listening to a non-native speaker, it would indicate a certain amount of control on the part of the listener over how disfluencies affect attention, and thus comprehension. Furthermore, it would argue against the hypothesis that disfluencies affect comprehension in a rather automatic fashion (cf. the Temporal Delay Hypothesis). Using the Change Detection Paradigm, we presented participants with three-sentence passages that sometimes contained a filled pause (e.g., “. that the patient with the uh wound was.”). After each passage, participants saw a transcript of the spoken passage in which one word had been substituted (e.g., “wound” > “injury”). In our first experiment, participants were more accurate in recalling words from previously heard speech (i.e., detecting the change) if these words had been preceded by a disfluency (relative to a fluent passage). Our second experiment - using non-native speech materials - demonstrated that non-native uh’s elicited an effect of the same magnitude and in the same direction: when new participants listened to a non-native speaker producing the same passages, they were also more accurate on disfluent (as compared to fluent) trials. These data suggest that, upon encountering a disfluency, listeners raise their attention levels irrespective of the (non-)native identity of the speaker. Whereas listeners have been found to modulate prediction effects of disfluencies when listening to non-native speech, no such modulation was found for memory effects of disfluencies in the present data, thus potentially constraining the role of listener control in disfluency processing. The current study emphasizes the central role of attention in an account of disfluency processing.
An Efficient Multi-keyword Symmetric Searchable Encryption Scheme for Secure Data Outsourcing

Symmetric searchable encryption (SSE) schemes allow a data owner to encrypt its data in such a way that it could be searched in encrypted form. When searching over encrypted data the retrieved data, search query, and search query outcome everything must be protected. A series of SSE schemes have been proposed in the past decade. In this paper, we are going to propose our an efficient multi-keyword symmetric searchable encryption scheme for secure data outsourcing and evaluate the performance of our proposed scheme on a real data set.