2,444 research outputs found
Energy harvesting using semi-active nonlinear control
No full textThis paper presents the application of semi-active control for power harvesting using an electromechanical energy harvester. Two semi-active control strategies are proposed in the form of a time-periodic damper and a nonlinear cubic damper. For the periodic time-varying damper the average harvested power and the throw are obtained based on the Fourier series. The semi-active periodic time-varying damper is optimised to maximise the harvested power. The performance of the optimum semi-active periodic damper is compared with the optimum passive and semi-active on-off model at a particular frequency. It is demonstrated that the periodic time-varying damper can significantly increase the harvested power at all frequencies of interest. For the nonlinear damper, the harvested power and the throw are derived using the concept of the describing function. The results are compared with the linear damper. It is demonstrated that the nonlinear damper can significantly increase the absorbed power despite having much lower displacement compared to the linear damper. This makes the semi-active nonlinear damper very attractive for mechanical energy harvesters
Investigating speech tempo, speaking rate, and the related factors in the iranian elderly women talking with tehrani and semnani accents
No full textBackground: Some variables, such as age, gender, regional and dialectical differences influence speech tempo. Men and younger individuals speak faster than women and the elderly. Therefore, these variations should be considered when assessing speaking rate. Objectives: Since different accents influence speaking rates and there is no previous study investigated speech tempo with respect to regional and accent differences in Iran, and given that the elderly are more prone to problems influencing speaking rate, the present study was done to compare speech tempo and speaking rate in two different accents, namely Tehrani and Semnani, and to investigate some related factors. Methods: This cross-sectional study was performed on 200 elderly women selected via convenience sampling method. Speech tempo, speaking rate, verbal fluency, and cognition scores were compared using an independent-samples t-test. Pearson�s correlation coefficient test was used to assess correlations between speaking rate and level of education, Montreal cognitive assessment (MoCA), and verbal fluency scores. Results: No significant difference was found in speech tempo between the studied accents (P = 0.13). Speaking rate was significantly slower in the Tehrani accent than the Semnani one (P = 0.04). The Tehrani elderly obtained significantly less scores in verbal fluency and MoCA ((P � 0.001) and (P = 0.04), respectively. In both groups, speaking rate had a significant correlation with verbal fluency and MoCA scores but not with level of education. Conclusions: Although, our results showed no difference in speech tempo between the studied accents, the Tehrani elderly unexpectedly spoke more slowly meaning that they paused more while speaking. There was a relationship between faster speaking, better verbal fluency, and cognitive performance. © 2021, Author(s)
Energy harvesting from train vibrations
No full textIn this paper, linear mechanical oscillators are designed to harvest energy from train-induced vibrations. The harvested energy could be used, for example, to charge sensors mounted on the rail track for structural health monitoring. The dominant frequencies due to a passing train are determined for a specific train and speed from a recorded acceleration time-history. Using a simple model of an oscillator, the total energy harvested for the passage of one train is calculated. The stiffness, and hence the tuning frequency of the device, is varied in simulations to determine the optimum frequency at which to tune the device for a constant value of mass and damping in the device. Further simulations are conducted to investigate the power that could be harvested from multiple oscillators tuned at several dominant frequencies, and their performances are analysed and compared. The constraint for maximum relative displacement is considered in the design of each harvester, and this is adopted to assure that the amplitude of the oscillation is finite and does not exceed the physical size of the device. The robustness of the harvester is also analysed for different train speeds
Studies in the mixed-mode analysis of partially prismatic thin-walled structures
No full textSIGLEAvailable from British Library Document Supply Centre- DSC:DX87374 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
INDIVIDUALISME FAISAL TEHRANI DALAM KEPENGARANGAN BERDASARKAN NOVEL-NOVEL TERPILIH
No full textFaisal Tehrani antara pengarang generasi baharu yang prolifik dan aktif berkarya sehingga kini. Karya-karya yang dihasilkannya menunjukkan kelainan tersendiri dari aspek tekstual dan kontekstual seiring dengan perubahan aliran, tema, persoalan dan pemikiran yang menjadi pegangan dalam menghasilkan karyanya. Sehubungan dengan itu, kajian ini bertujuan untuk menganalisis pembinaan jati diri beliau dalam novel-novel terpilihnya. Sepanjang berkarya, beliau menghasilkan novel remaja dan novel dewasa bagi menyampaikan pemikiran, persoalan, permasalahan, mesej dan sebagainya dengan berkesan. Sebanyak lima buah novel akan ditelusuri, iaitu Perempuan Politikus Melayu, 1515, 1511H[Kombat], SsPJ, Tunggu Teduh Dulu dan Bahlut. Kajian ini menggunakan metodologi kualitatif yang melibatkan pembacaan rapi dan pentafsiran sumber bertulis. Bagi menganalisis pembinaan jati diri, Teori Teksdealisme digunakan sebagai landasan kajian. Dalam Teori Teksdealisme telah mengemukakan prinsip individualisme atau keperibadian untuk mengesan keupayaan seseorang pengarang untuk membina jati diri atau keperibadiannya. Bagi mengesan pembinaan individualisme tersebut, prinsip ini telah mengemukakan empat unsur yang diterokai, iaitu subjektiviti, stail individu, reka cipta individu dan tindakan individu. Semua unsur tersebut dianalisis secara tekstual dan konstektual berdasarkan tujuan dan persoalan kajian yang ditetapkan. Kajian mendapati bahawa Faisal Tehrani berusaha untuk membina dan menampilkan jati diri kepengarangannya melalui subjektiviti, stail individu, reka cipta individu dan tindakan individu. Keupayaan membina individualisme ini akan mengukuhkan kedudukan serta ketokohan beliau sebagai pengarang yang memiliki ciri-ciri keunggulan kerana mempunyai ideologi, kreativiti, sensitiviti dan matlamat tersendiri dalam menghasilkan novel-novelnya.
Faisal Tehrani is among the new generation of prolific and active authors today. His works show distinct uniqueness in the textual and contextual aspects in terms of the changes in the flow, themes, problems and thoughts that come into being in producing his works. Accordingly, this study aims to analyze the development of his identity in his selected novels. Throughout his creative production, he has produced various teen and mature novels to effectively communicate his ideas, questions, problems, messages, etc. A total of five novels was studied, namely Perempuan Politikus Melayu, 1515, 1511H [Kombat], SsPJ, Tunggu Teduh Dulu and Bahlut. This study will apply a qualitative methodology involving intensive reading and interpretation of written sources. To analyze the development of identity, the texdialism theory will be used as the basis of the study. The Texdialism Theory puts forward the principles of individualism or individuality to detect the ability of an author to build his identity or personality. To track the construction of the individualism, this approach presented four exploratory elements, namely subjectivity, individual style, individual inventor and individual action. All of these elements will be analysed textually and consistently based on the objectives and questions of the study. The study found that Faisal Tehrani sought to build and display his identity through subjectivity, individual styles, individual inventions and individual actions. The ability to build this individualism will reinforce his position as an author who has the characteristics of excellence because of his ideology, creativity, sensitivity and purpose in producing his novels
A new semi-nonverbal task glance, moderate role of cognitive flexibility in ADHD children’s theory of mind
No full textSeveral studies have documented executive functions' impairment in children with ADHD and the link between Theory of Mind, executive functions and ADHD with different results. The findings in the literature are somewhat mixed, possibly because of a variety of tasks used. The aim of this study is to investigate the relationship between ToM and Executive Functions with nonlanguage based tasks. 30 ADHD children (7-9 years old) and 30 controls (age and IQ matched). All participants ToM were assessed using the Animated Triangles Paradigm task and two EF task (IED and SOC) from the neuropsychological battery of the Cambridge Neuropsychological Test Automated Battery. Children with ADHD had a significant ToM and EF impairment relative to the control group. ToM was not significantly correlated with ET however, the performance on IED tasks affected the performance on ToM tasks. The study provides evidence for a link between intentionality subcomponent of ToM and inhibitory control of EF in ADHD children, which supports the hypothesis that inhibition may play a central role to explain the association between ToM and EF
Towards an archaeology of pedagogy: learning, teaching and the generation of material culture traditions
No full textIn this article we seek to build on efforts to apply the insights of social learning theory to interpret patterns of continuity and change in the archaeological record. This literature suggests that stable and often highly arbitrary material culture traditions are likely to be founded on our biologically evolved capacity for imitation. However, it has recently been argued that the latter may be insufficient to explain the long-term maintenance of complex and difficult-to-master skills, such as those required to produce stone tools, pots, textiles and other cognitively opaque cultural forms. To ensure that these skills are accurately transferred to the next generation, adults must actively guide and control the learning activities of their children, a mode of transmission that can be labelled 'pedagogy'. The importance of pedagogy has often been overlooked in the theoretical and empirical literature on craft learning, a fact that can probably be attributed to an unnecessarily narrow conception of teaching that equates it with explicit linguistic instruction. Using ethnographic data gathered from detailed case studies, we characterize pedagogy in the context of craft apprenticeships as involving the gradual scaffolding of skill in a novice through demonstration, intervention and collaboration. Although these processes cannot be directly observed in the archaeological record, they can sometimes be inferred through the detailed reconstruction of operational chains in past technologies. The evidence we present suggests that pedagogy has played an essential role in securing the faithful transmission of skills across generations, and should be regarded as the central mechanism through which long-term and stable material culture traditions are propagated and maintained
Using datasets from industrial control systems for cyber security research and education
No full textThe availability of high-quality benchmark datasets is an important prerequisite for research and education in the cyber security domain. Datasets from realistic systems offer a platform for researchers to develop and test novel models and algorithms. Such datasets also offer students opportunities for active and project-centric learning. In this paper, we describe six publicly available datasets from the domain of Industrial Control Systems (ICS). Five of these datasets are obtained through experiments conducted in the context of operational ICS while the sixth is obtained from a widely used simulation tool, namely EPANET, for large scale water distribution networks. This paper presents two studies on the use of the datasets. The first study uses the dataset from a live water treatment plant. This study leads to a novel and explainable anomaly detection method based upon Timed Automata and Bayesian Networks. The study conducted in the context of education made use of the water distribution network dataset in a graduate course on cyber data analytics. Through an assignment, students explored the effectiveness of various methods for anomaly detection. Research outcomes and the success of the course indicate an appreciation in the research community and positive learning experience in education.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Cyber SecurityNetwork Architectures and Service
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