Contributions of KARDS to Professional Identity of High School Teachers in an EFL Context

This research aimed at investigating the impacts of knowing, analyzing, recognizing, doing, and seeing (KARDS) on Iranian English as a foreign language (EFL) teachers’ professional identity reconstruction in the context of high schools. Purposive sampling and KARDS questionnaire were used to choose participants and to classify them into a more KARDS-oriented group (n=10) and a less-KARDS oriented group (n=10). The researchers employed pre-course and post-course interview, teacher educator’s and teachers’ reflective journals, and class debate as data gathering tools. Following the pre-course interview, there was an implementation phase of KARDS by means of which teachers were acquainted with it. Then, Grounded Theory was used for data analysis. Findings revealed that there were three big shifts from “uncertainty of practice to certainty of practice”, “the use of fewer macro-strategies to the use of more macro-strategies”, and “linguistic and technical view of language teaching to critical, educational, and transformative view of language teaching” in teachers’ professional identities in both groups. The changes were similar in quality but not in quantity, and they should be incorporated in teacher education programs. The findings may encourage stakeholders to welcome uncertainty and confusion, to underline more macro-strategies, and to take a critical and transformative view of language teaching in language classrooms

Channel Coding at Low Capacity

Low-capacity scenarios have become increasingly important in the technology of the Internet of Things (IoT) and the next generation of mobile networks. Such scenarios require efficient and reliable transmission of information over channels with an extremely small capacity. Within these constraints, the performance of state-of-the-art coding techniques is far from optimal in terms of either rate or complexity. Moreover, the current non-asymptotic laws of optimal channel coding provide inaccurate predictions for coding in the low-capacity regime. In this paper, we provide the first comprehensive study of channel coding in the low-capacity regime. We will investigate the fundamental non-asymptotic limits for channel coding as well as challenges that must be overcome for efficient code design in low-capacity scenarios.Comment: 39 pages, 5 figure

A Design Method to Exploit Synergies Between Fiber-Reinforce Composites and Additive Manufactured Processes

This paper proposes a design method for devices composed of long fiber-reinforced composites (FRC) and additive manufactured (AM) parts. Both FRC and AM processes have similar application characteristics: suitable for small production volumes, additive in nature, and capable of being highly automated. On the other hand, the classes have distinct characteristics. FRCcomponents tend to be large and of simple shapes, while AM components tend to be small with highly complex geometry. Their combination has the potential for significant synergies, while mitigating their individual limitations. A decision guide is proposed, in the form of a series of questions, to guide the designer to determine if their application is a good candidate for FRC+AM. The decision guide is reformulated into a proposed design process that guides the designer to advantageously benefit from AM and FRC characteristics. The tools are illustrated with an example of a composite pressure vessel with integrated pressure reducer

Supervisory Control of Line Breakage for Thruster-Assisted Position Mooring System

Thruster-assisted position mooring (TAPM) is an energy-efficient and reliable stationkeeping method for deep water structures. Mooring line breakage can significantly influence the control system, and ultimately reduce the reliability and safety during operation and production. Therefore, line break detection is a crucial issue for TAPM systems. Tension measurement units are useful tools to detect line failures. However, these units increase the building cost of the system, and in a large portion of existing units in operation line tension sensors are not installed. This paper presents a fault-tolerant control scheme based on estimator-based supervisory control methodology to detect and isolate a line failure with only position measurements. After detecting a line break, a supervisor switches automatically a new controller into the feedback loop to keep the vessel within the safety region. Numerical simulations are conducted to verify the performance of the proposed technique, for a turret-based mooring system.© 2015, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved. This is the authors’ accepted and refereed manuscript to the articl

A multiple model adaptive architecture for the state estimation in discrete-time uncertain LPV systems

@2017 Personal use of these materials is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating news collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksThis paper addresses the problem of multiple model adaptive estimation (MMAE) for discrete-time linear parameter varying (LPV) systems that are affected by parametric uncertainty. The MMAE system relies on a finite number of local observers, each designed using a selected model (SM) from the set of possible plant models. Each local observer is an LPV Kalman filter, obtained as a linear combination of linear time invariant (LTI) Kalman filters. It is shown that if some suitable distinguishability conditions are fulfilled, the MMAE will identify the SM corresponding to the local observer with smallest output prediction error energy. The convergence of the unknown parameter estimation, and its relation with the varying parameters, are discussed. Simulation results illustrate the application of the proposed method.Peer ReviewedPostprint (author's final draft

Optimal Network Topology for Effective Collective Response

Natural, social, and artificial multi-agent systems usually operate in dynamic environments, where the ability to respond to changing circumstances is a crucial feature. An effective collective response requires suitable information transfer among agents, and thus is critically dependent on the agents' interaction network. In order to investigate the influence of the network topology on collective response, we consider an archetypal model of distributed decision-making---the leader-follower linear consensus---and study the collective capacity of the system to follow a dynamic driving signal (the "leader") for a range of topologies and system sizes. The analysis reveals a nontrivial relationship between optimal topology and frequency of the driving signal. Interestingly, the response is optimal when each individual interacts with a certain number of agents which decreases monotonically with the frequency and, for large enough systems, is independent of the size of the system. This phenomenology is investigated in experiments of collective motion using a swarm of land robots. The emergent collective response to both a slow- and a fast-changing leader is measured and analyzed for a range of interaction topologies. These results have far-reaching practical implications for the design and understanding of distributed systems, since they highlight that a dynamic rewiring of the interaction network is paramount to the effective collective operations of multi-agent systems at different time-scales

A Survey on Process Modelling, Innovation, Design, and Material Characterisation in Additive Manufacturing

The unique design freedom offered by additive manufacturing (AM) technologies enables engineers to develop more innovative products with relatively lower costs within a shorter period of processing time in comparison with conventional manufacturing methods. On the other hand, the unique capabilities of AM have created a platform for researchers to combine several engineering methods with the new manufacturing technique to grow industrial applications as well as resolve the existing issues with AM processes. Understanding the research values that AM offers academic environments, this paper performs a systematic survey on AM-related research topics in the fields of mechanical engineering and materials science that have attracted much attention from research teams over the last few years. These topics, namely process modelling in AM, innovative research in AM, generative design by AM, material characterisation in AM processes, and finally, design for additive manufacturing (DfAM), are notably investigated through this study

Form-Finding and Structural Shape Optimization of the Metal 3D-Printed Node

In the last few years, considerable attention has been paid to additive manufacturing (AM) technologies to redesign and modify the industrial products with regard to its merits. At the initial stage of technology development, AM was mostly used as a building platform for prototyping, whereas its usage has been recently extended to industrial applications. Amid the different methods of AM technology, the development of metal AM, in particular, Powder Bed Fusion (PBF) and metal Binder Jetting (MBJ), facilitate the production of high-quality and complex parts in several sectors of industry such as aerospace, medical, architecture and civil engineering. Understanding the novel advantage of metal 3D-printing in the development of high-performance and functional parts for applications in the construction sector enables researchers to propose different design and form-finding methods for construction components

Treatment of Necrotic Teeth Using Two Engine-Driven Systems and Patient’s Postoperative Pain: A Double-Blind Clinical Trial

Introduction: One of the most important reasons for postoperative pain is the extrusion of debris from the apical foramen during preparation and shaping of root canals. The aim of this clinical trial was to evaluate the severity of postoperative pain with the use of two different engine-driven NiTi systems. Methods and Materials: Ninety mandibular molars were randomly divided into two groups (n=45), and root canal cleaning and shaping was done using either RaCe or Reciproc instruments. The severity of postoperative pain was determined with visual analogue scale (VAS) at 4-, 12-, 24-, 48- and 72 h and 1-week intervals and postoperative pain was compared between the two groups. The chi-squared test and repeated-measures analysis were used to compare the data between the two groups. Results: Based on the results of the statistical analyses, the two groups were matched regarding the age and gender, with no significant differences. In addition, except for 4- and 24-h and 1-week intervals, postoperative pain was significantly less in the RaCe group compared to the Reciproc group (P<0.001). Conclusion: Based on the results of the present study, use of RaCe files for cleaning and shaping of root canals in necrotic mandibular molars resulted in less severe postoperative pain compared to Reciproc files.Keywords: Necrotic Teeth; Postoperative Pain; RaCe Files; Reciproc Files; Visual Analogue Scal

Allelopathy of sage and white wormwood on purslane germination and seedling growth.

A bioassay run was carried out in the incubator to evaluate possible allelopathic effects of water extracts of sage and white wormwood on germination and seedling growth of purslane. Results showed that the type of extract and its concentration (0, 5, 10, 15 and 20%) significantly influenced final germination percentage, germination rate and index, root and shoot length, root/shoot ratio, fresh and dry weight of seedling of purslane. The interaction between these two experimental factors was always significant, producing different results according to the different combination levels. The statistical comparison of means indicated that the maximum germination percentage and germination rate (respectively 68% and 11.4% d-1) were obtained from the untreated control (0% extract), while the lowest values for the same two characters occurred with 15% of sage (respectively 45% and 6.4% d-1) and 20% of white wormwood (38% and 7.5% d-1). Concerning germination indexes, the highest (55) and the lowest (32) values were observed respectively on the control and with 15% of sage extract or 20% of white wormwood extract. The longest (4.5 cm) and the shortest (1.3 cm) root of purslane were obtained with 5% of white wormwood and 20% of sage extracts, respectively. Changes in shoot length with sage and white wormwood extracts were similar to those in root length, even though shoot length was less affected by the concentration of extracts. Root and shoot length changes brought to maximum (22.0) and minimum (8.9) values for the root/shoot length ratio, respectively with 5% of white wormwood and 20% of sage extracts. The maximum fresh (2.111 g) and dry (0.338 g) seedling weight of purslane were obtained from untreated control, producing the same seedling weight with 5% of sage, 5 and 10% of white wormwood extract. While the minimum fresh (0.692 g) and dry (0.111 g) seedling weight were obtained from 15% of white wormwood extract, so that there is no significant differences between this value and the seedling weight produced under 10, 15 and 20% of sage and 20% of white wormwood extract