Towards the development of a problem solver for the monitoring and control of instrumentation in a grid environment

This paper considers the issues involved in developing a generic problem solver to be used within a grid environment for the monitoring and control of instrumentation. The specific feature of such an environment is that the type of data to be processed, as well as the problem, is not always known in advance. Therefore, it is necessary to develop a problem solver architecture that addresses this issue. We propose to analyze the performance of the problem solving algorithms available within the WEKA toolkit and determine a decision tree of the best performing algorithm for a given type of data. For this purpose the algorithms have been tested using 51 datasets either drawn from publicly available repositories or generated in a grid-enabled environmen

Absolute spectroscopy near 7.8 μm with a comb-locked extended-cavity quantum-cascade-laser

We report for the first time the frequency locking of an extended-cavity quantum-cascade-laser (EC-QCL) to a near-infrared frequency comb. The locked laser source is exploited to carry out molecular spectroscopy around 7.8 μm with a line-centre frequency combined uncertainty of ~63 kHz. The strength of the approach, in view of an accurate retrieval of line centre frequencies over a spectral range as large as 100 cm-1, is demonstrated on the P(40), P(18) and R(31) lines of the fundamental rovibrational band of N2O covering the centre and edges of the P and R branches. The spectrometer has the potential to be straightforwardly extended to other spectral ranges, till 12 μm, which is the current wavelength limit for commercial cw EC-QCLs

Temporal Differences in the Emission and Atmospheric Dispersion of Particulate Matter From Waste and Drinking Water Treatment Facilities

Many countries encounter a growing shortage of water, and the reuse of treated or untreated wastewater is their main source. Wastewater Treatment Plants (WWTPs) are mainly designed to remove organic nutrients, large solids, and chemical substances. There are some possible issues regarding WWTPs that are close to residential areas around the world. One of the environmental effects from WWTP that might cause air pollution would be the emission of toxic chemical gases and microorganisms via aerosols that transport bacteria as well as viruses and fungal spores which can be harmful to human health. Therefore, particulate matters (PM) and metrological parameters samples were collected from four WWTPs to examine the spatial and temporal differences in their emissions and dispersions. Geographic Information System (GIS) was used to visualize the predicted PM concentrations from 50 meters to 500 meters around WWTPs sites. We found that there are some seasonal, treatment methods and daily statistical significance variations in the total particulate matters and particulate number by diameter between the four sites

Determinants of Employee Performance Evaluation in Service Sector Businesses of United States

This cross-sectional study investigates the relationships between work environment, supervision, compensation, job satisfaction, and performance outcomes within the service sector of organizations in the United States. Using convenience sampling, data was collected from 291 participants through online surveys. The study employs comprehensive analysis techniques, including path analysis and mediation analysis, to examine the direct and mediated effects of organizational factors on performance outcomes through job satisfaction. The findings underscore the pivotal role of job satisfaction as a central mediator, transmitting the influence of work environment, supervision, and compensation onto performance metrics. The study highlights the significance of fostering conducive work environments, supportive leadership, and fair reward systems to enhance job satisfaction. Furthermore, it demonstrates the tangible impact of job satisfaction on various performance outcomes, including task performance, adaptive performance, and contextual performance. These findings provide valuable insights for organizational management strategies aimed at improving employee well-being and organizational effectiveness in the service sector

La déformation de la plaque supérieure dans les zones de subduction en retrait

The Earth’s surface is constantly reshaped by the tectonic plate motion, which is mainly driven by subduction of plates into the deeper mantle. Subduction trenches are also mobile plate boundaries, and are observed to retreat towards the subducting plate or advance towards the upper plate over geological time. Trench retreat has been historically thought to cause extension in the upper plate above the subducting slab. However, natural subduction systems show several examples of retreating trenches that are associated with upper-plate compression. This thesis explores upper plate (back-arc) deformation in retreating subduction systems. Three techniques are used: large-scale numerical models addressing physical processes; seismic profiles in the Central Aegean addressing basin-scale fault patterns; and field-scale observations clarifying fault kinematics in the Central Aegean. The large-scale thermo-mechanical models deal with viscous deformation of the upper plate, and investigate the relationship between slab pull, slab rollback, trench retreat and upper plate deformation at scales of 100 to 1000 km. They show that asthenosphere flows below the plates (100-200 km depth) can control both trench retreat and upper plate deformation. The type of deformation in the upper plate also depends on the plate’s far-field conditions: if the plate is free to move, deformation tends to be compressive, but a fixed upper plate shows extension. The latter is comparable to the Aegean region, an upper plate exhibiting extension above a narrow, retreating subduction zone. Related extensional structures in the central Aegean have been analysed from seismic and field data, revealing co-existing normal, oblique and strike slip faults. These features reflect a combination of rollback-related extension and extrusion-related strike slip activity. Resulting block rotation and trench retreat re-activate inherited normal faults in oblique-normal slip, while new pure-normal faults are created. We also infer a recent change in stress state possibly related to the slab tear on the western side of the Hellenic slab. Additionally, accelerated trench retreat and upper plate extension are the cause of the Aegean’s high surface heat flow, which makes it potentially suitable for geothermal energy production. As a final perspective on the application of geodynamic research, an assessment of the role of tectonic modelling in predicting geothermal energy potential is presented, using the stretched Aegean upper plate as an example.La surface de la Terre est en permanence remodelée par les mouvements des plaques tectoniques, dont le moteur principal est la subduction, i.e. le plongement de plaques océaniques dans le manteau profond. Les fosses océaniques de subduction constituent également des limites de plaques mobiles, et les observations montrent que, sur des échelles de temps géologiques de plusieurs millions d’années, ces fosses reculent (vers la plaque plongeante) ou avancent (vers la plaque chevauchante/supérieure). Historiquement, le retrait de la fosse a été associé à une extension de la plaque supérieure au-dessus du panneau plongeant. Cependant, les zones de subduction sur Terre montrent plusieurs exemples de fosses en recul associées à des contraintes compressives. Cette thèse étudie la déformation (arrière-arc) de la plaque supérieure pour une subduction en retrait. Trois approches ont été utilisées : des modèles numériques explorant les processus physiques mis en jeu à grande échelle, des profils sismiques en mer Égée centrale permettant d’étudier la répartition des failles à l’échelle du bassin, et des observations de terrain pour caractériser l’évolution temporelle de la déformation de la plaque supérieure en mer Égée centrale. Les modèles thermo-mécaniques à grande échelle reproduisent une déformation visqueuse de la plaque supérieure, et permettent d’analyser les relations entre traction du slab, recul du slab, retrait de la fosse et déformation de la plaque supérieure, à des échelles allant de 100 à 1000 km. Ils montrent que des courants dans le manteau asthénosphérique sous les plaques (vers 100-200 km de profondeur) peuvent contrôler à la fois le mouvement relatif de la fosse et la déformation de la plaque supérieure. Cette dernière dépend également des conditions mécaniques aux limites: si la plaque est libre de bouger, sa déformation sera plutôt compressive ; mais une plaque fixe sera en extension. Ce dernier cas est comparable à la région de la mer Égée, une plaque supérieure montrant de l’extension et associée à une zone de subduction étroite en retrait. Les structures extensives associées ont été analysées grâce à l’observation sur le terrain et à l’étude de profils sismiques, révélant des failles normales, obliques et décrochantes synchrones. Cela est interprété comme résultant de la combinaison de contraintes extensives associées au recul de la fosse et de contraintes décrochantes associées à l’extrusion d’un bloc voisin. La rotation et le recul de la fosse réactivent d’anciennes failles normales dans un mode oblique-extensif, et engendrent des nouvelles failles purement normales. Les données suggèrent également un changement récent de l’état de contrainte mécanique dans la plaque, qui pourrait être dû à une déchirure du panneau plongeant côté Ouest. En sus, l’accélération du recul de la fosse et l’intensification de l’extension de la plaque supérieure expliquent probablement le flux de chaleur élevé en mer Égée, ce qui rend l’énergie géothermique potentiellement exploitable dans cette zone. Une évaluation de l’apport de la modélisation tectonique pour prédire le potentiel géothermique est finalement présentée comme perspective de l’application des recherches en géodynamique, s’appuyant sur l’exemple de la plaque supérieure égéenne amincie

An Investigation of Student Interaction Patterns and Teacher Feedback at a Saudi EFL University Context

The current study is guided by the assumption that classroom interaction plays a key role in enhancing the quality of learning and teaching in a classroom setting. In an EFL context as this study concerns classroom interaction becomes more essential as it cannot merely increase the opportunities for learning the language but also allow students to practise using the target language by participating in classroom activities and interacting with both their teachers and peers. To date, there have been many research studies conducted for the purpose of fostering student communication and interaction in language learning contexts. The current study aimed at investigating different patterns of classroom interaction take place in a particular English classrooms context. The IRF: Initiation, Response, and Feedback patterns of classroom discourse investigated in this study are one of the most common structures of classroom interaction. The study conducted an exploratory study using two qualitative methods (i.e. observation and interviews) to answer two main research questions. Particularly, how EFL teachers use the third feedback turn of interaction whether for evaluation feedback and then closure of the cycle of interaction at this level, or follow-up feedback to maintain the flow of interaction. The data of the study identified five functions of the feedback the teachers employed in the classrooms observed. It is found that the teachers use the feedback turns: to initiate new questions; to make the discourse more communicative; to promote student engagement and contributions; and lastly to provide an embedded and explicit evaluation. In addition, the study investigated the teachers’ perspectives of, and insights into, the functions of the feedback they provide. It is found that the teachers provided four different ways of scaffolding to extend student participation and communication. Finally, some contributions, implications for the context and recommendations are provided as well as some suggestions for improving classroom discourse in light of future consideration

Plasmon resonances of highly doped two-dimensional MoS2

The exhibition of plasmon resonances in two-dimensional (2D) semiconductor compounds is desirable for many applications. Here, by electrochemically intercalating lithium into 2D molybdenum disulfide (MoS2) nanoflakes, plasmon resonances in the visible and near UV wavelength ranges are achieved. These plasmon resonances are controlled by the high doping level of the nanoflakes after the intercalation, producing two distinct resonance peak areas based on the crystal arrangements. The system is also benchmarked for biosensing using bovine serum albumin. This work provides a foundation for developing future 2D MoS2 based biological and optical units