Strain engineered In_xGa_1-xAs channel pHEMTs on virtual substrates: a simulation study

The impact of In<sub>x</sub>Al<sub>1-x</sub>As strain control buffers on the performance of low In content InGaAs channel pseudomorphic high electron mobility transistor p(HEMT) is investigated. It is shown that relaxed and tensile strained channel devices outperform the conventional compressively strained channel devices. It is argued that strain engineering in GaAs based devices makes it possible to realise RF characteristics comparable to InP based pHEMTs while obtaining improved breakdown characteristics

RF performance of strained Si MODFETs and MOSFETs on "virtual" SiGe substrates: A Monte Carlo study

No abstract avaliable

Simple approach to include external resistances in the Monte Carlo simulation of MESFETs and HEMTs

The contact and external series resistances play an important role in the performance of modern 0.1-0.2 μm HEMT's. It is not possible to include these resistances directly into the Monte Carlo simulations. Here we describe a simple and efficient way to include the external series resistances into the Monte Carlo results of the intrinsic device simulations. Examples of simulation results are given for a 0.2 μm pseudomorphic HEMT

‘Am I employable?’: Understanding students' employability confidence and their perceived barriers to gaining employment

This paper addresses employability among undergraduate Marine Sport Science students' at a post-92 HEI in the UK, focusing on perceptions of employability and confidence in gaining graduate employment after having careers education embedded within their programme. Results (69% of cohort/n=57) showed that Marine Sport Science students' perception of their employability increased year on year whilst conversely, confidence in gaining graduate employment decreased year on year. This was due to seven perceived barriers: competition, experience, location, degree quality, qualifications, economy and confidence. The 'diving board theory' was established explaining the juxtaposition of improving perceived employability alongside decreasing confidence in gaining employment

The escape behaviour of wild Greek tortoises Testudo graeca with and emphasis on geometrical shape discrimination

Geometrical shape discrimination has been shown to play an important role in the spatial orientation of a wide variety of mammals and birds, while the study of this ability in particular and of cognitive processes in general has been rather neglected in reptiles. The present experiment aims to investigate the ability of wild Greek tortoises Testudo graeca from Topolog forest, Tulcea County, Romania, to discriminate between simple geometrical shapes. Forty-two adult tortoises were subjected to a task consisting of escaping from a square arena through one of the four available doors, each with a geometrical shape attached. Thirty-one individuals completed ten consecutive trials, requiring significantly less time for the last trial than for the first. This trend suggests that Greek tortoises developed and used an escape strategy, most likely relying on the geometrical shapes provided as cues. This experiment is the first to explore the cognitive processes of this species and further work should expand on the ecological significance of this ability

Optimizing egalitarian performance in the side-effects model of colocation for data center resource management

In data centers, up to dozens of tasks are colocated on a single physical machine. Machines are used more efficiently, but tasks' performance deteriorates, as colocated tasks compete for shared resources. As tasks are heterogeneous, the resulting performance dependencies are complex. In our previous work [18] we proposed a new combinatorial optimization model that uses two parameters of a task - its size and its type - to characterize how a task influences the performance of other tasks allocated to the same machine. In this paper, we study the egalitarian optimization goal: maximizing the worst-off performance. This problem generalizes the classic makespan minimization on multiple processors (P||Cmax). We prove that polynomially-solvable variants of multiprocessor scheduling are NP-hard and hard to approximate when the number of types is not constant. For a constant number of types, we propose a PTAS, a fast approximation algorithm, and a series of heuristics. We simulate the algorithms on instances derived from a trace of one of Google clusters. Algorithms aware of jobs' types lead to better performance compared with algorithms solving P||Cmax. The notion of type enables us to model degeneration of performance caused by using standard combinatorial optimization methods. Types add a layer of additional complexity. However, our results - approximation algorithms and good average-case performance - show that types can be handled efficiently.Comment: Author's version of a paper published in Euro-Par 2017 Proceedings, extends the published paper with addtional results and proof

Gate recess engineering of pseudomorphic In0.30GaAs/GaAs HEMTs

The authors report how the performance of 0.12 μm GaAs pHEMTs is improved by controlling both the gate recess width, using selective dry etching, and the gate position in the source drain gap, using electron beam lithography. pHEMTs with a transconductance of 600 mS/mm, off state breakdown voltages >2 V, fτ of 120 GHz, f max of 180 GHz and MAG of 13.5 dB at 60 GHz are reported

Lonely heart columns: A novel and entertaining way of teaching students abstract writing skills

Abstract writing is a key skill for science graduates; they are a common feature in many of the standard forms of scientific dissemination such as scientific research articles. In this paper we present a novel and entertaining approach for teaching abstract writing using adverts from lonely heart columns (LHC). Student constructed full profiles of the authors of LHC and constructed LHC profiles of celebrities to illustrate the key sills in abstract construction. There was no significant difference between the grades achieved by student taught using LHC and a more traditional approach, suggesting there were no negative impacts from this delivery method. Student in LHC tutorial overwhelmingly enjoy the tutorial, 95% responded the question ‘how would you rate the enjoyment of this tutorial’ as ‘much’ or ‘very much’. In addition to abstract writing two thirds of students in LHC tutorial believed they improved their ability to speak in front of others and their creative thinking skills. The LHC tutorial is a novel approach to teaching and learning that is both enjoyable and effective

The influences of capital development strategies choice on international management students' collaborative knowledge creation: Turkey and Ecuador

The paper presents the first phase of international (four countries) study that explores the influence of social capital and personal learning networks (PLN) development approaches used by international management students in multicultural learning environments and the types of social and academic networks they develop on their collaborative knowledge and cross-cultural competence development, in particular, on their preparation for international careers. A comparative analysis is conducted within four international programs (in Turkey, Ecuador, UK and US) that offer international education in English language for local and international students. The paper presents the preliminary results of a comparison in two locations – Turkey and Ecuador. The study applies the concepts of collaborative knowledge development, social capital and social networks. The study uses constructivist grounded theory [1] to uncover the process of social capital and collaborative knowledge creation. Based on the data, collected through semi-structured interviews, and analyzed through dımensıonal analysis [2]; [3], the study develops a process model, which takes into account the core social identity of the learner, as well as the existing and emergent social personal learning ties, built on social capital. An additional goal of the study is to uncover the overlapping social and personal learning networks international and local students participate in and develop, to trace the knowledge sharing routes and to pinpoint knowledge creation hubs in these networks. As the result of the study, recommendations are developed for higher educational institutions (HEIs) and multinational enterprises (MNEs) regarding the steps they can take to promote collaborative and cross-cultural knowledge creation among their members. The connectivism theory of social learning [4] suggests loose and pragmatic ties appropriate to knowledge sharing and creation in the interconnected networked social reality of the 21st century as they combine social and informational resources that operate in a chaotic environment and recognize rather than create patterns of meaning. While we are not proposing any final theoretical models at this point, it is likely that the learners who are engaged in multi-dimensional and loosely connected PLNs characterized by multiple networks consisted of weak ties and who utilize problem solving models of knowledge creation are more likely to become cross/interculturally competent and are more likely to be prepared for global careers. However, the preliminary findings show that international students lack the skills and desire to create functional PLNs and tend to engage in multiple binding networks characterized by strong emotional bonds but limited knowledge creation. While is it premature at this stage to suggest any specific steps that IHEIs and other multicultural learning environments might take to encourage social and technological networking among international students and other members of academic environment, some tentative recommendations are presented