6,829 research outputs found
A Critique of the Computer-Based English Speaking Test in Fujian (CEST-FJ)
This essay applies Bachman and Palmer’s (1996) Test Usefulness Framework to scrutinize the reliability, construct validity, and impact of the Computer-based English Speaking Test in Fujian (CEST-FJ). The CEST-FJ’s inclusion in the National College Entrance Examination (NCEE) represents a positive step towards promoting communicative ability in English language learning in China. The computerized administration and scoring processes enhance the test’s reliability and control over construct-irrelevant variance. However, limitations such as potential variations in difficulty, construct under-representation of communicative competence, challenges for pronunciation assessment in the context of English as an International Language (EIL), and the non-compulsory and low-value nature of the test have been identified. Additionally, the lack of transparency surrounding the CEST-FJ hampers assessment and accountability. This essay emphasizes the need for more theoretical and empirical research to justify or enhance the test in the future, particularly in light of its high-stakes nature and influence on test-takers’ university admissions. Test designers are urged to prioritize transparency and provide more information to facilitate further research and ensure the effectiveness of the CEST-FJ
Single-drive high-speed lumped depletion-type modulators toward 10 fJ/bit energy consumption
Reduction of modulator energy consumption to 10 fJ/bit is essential for the sustainable development of communication systems. Lumped modulators might be a viable solution if instructed by a complete theory system. Here, we present a complete analytical electro-optic response theory, energy consumption analysis, and eye diagrams on absolute scales for lumped modulators. Consequently the speed limitation is understood and alleviated by single-drive configuration, and comprehensive knowledge into the energy dependence on structural parameters significantly reduces energy consumption. The results show that silicon modulation energy as low as 80.8 and 21.5 fJ/bit can be achieved at 28 Gbd under 50 and 10 Omega impedance drivers, respectively. A 50 Gbd modulation is also shown to be possible. The analytical models can be extended to lumped modulators on other material platforms and offer a promising solution to the current challenges of modulation energy reduction. (C) 2017 Chinese Laser PressNational Natural Science Foundation of China (NSFC) [61120106012]SCI(E)ARTICLE2134-142
Hydrogen sulfide-induces DNA damage and changes in apoptotic gene expression in human lung fibroblast cells
10.1096/fj.06-6255comFASEB Journal211247-25
Fabbisogni energetici per edifici caratterizzanti il terziario in Italia: aspetti termici ed illuminotecnici
Il presente lavoro verte sull'individuazione di benchmark di fabbisogno energetico per edifici di riferimento con destinazione d'uso non-residenziale. In particolare, si intende fornire profili tipo di domanda energetica per l'illuminazione artificiale, al fine di valutarne l'effetto sui profili di fabbisogno di energia per la climatizzazione estiva ed invernale, nonché di individuare le variabili che maggiormente incidono sulla loro determinazione. Per giungere a questi risultati, ci si avvale dell'uso di programmi informatici di simulazione dinamica riconosciuti ed impiegati a livello scientifico, in ambito europeo ed extraeuropeo (Energy Plus). La ricerca viene condotta sotto vari aspetti: architettonico, energetico e ambientale. Il primo obiettivo, partendo dalle indicazioni bibliografiche, legislative e normative, è quello di caratterizzare in modo univoco gli edifici di riferimento per le varie destinazioni d'uso oggetto di analisi: edifici per l'istruzione, ed edifici terziari. Gli edifici di riferimento intendono costituire archetipi rappresentativi del patrimonio edilizio italiano. Il secondo obiettivo è di tipo energetico: si intende definire profili tipo di domanda energetica per l'illuminazione artificiale degli ambienti. Si intendono inoltre valutare contestualmente i fabbisogni energetici netti per il riscaldamento e il raffrescamento degli ambienti. L'obiettivo finale è riuscire a determinare le migliori soluzioni progettuali per la minimizzazione del fabbisogno di energia connesso all'illuminazione, in relazione alle destinazioni d'uso dei differenti edifici, nonché le variabili che più incidono per indirizzare al meglio le attenzioni progettuali in caso di nuova realizzazione. Il presente lavoro, dopo un primo inquadramento generale in cui si delinea quello che è lo stato dell'arte della valutazione dei fabbisogni energetici e della ricerca scientifica in materia di illuminazione artificiale di ambienti non residenziali, passa poi ad indagare il significato di archetipo e a definire degli archetipi edilizi per il patrimonio immobiliare costruito a destinazione d'uso scolastica e terziaria. Successivamente vengono descritti i modelli di calcolo impiegati e sono dettagliati i dati di input impiegati per la loro definizione. Sono infine esplicati i risultati ottenuti, con individuazione dei valori di benchmark energetico per gli archetipi edilizi scolastici e terziari, e con l'analisi di quelle che sono le grandezze maggiormente influenti sul fabbisogno energetico per illuminazion
Modeling and Simulation of Public Opinion Evolution Based on the SIS-FJ Model with a Bidirectional Coupling Mechanism
The evolution of public opinion on social media affects societal security and stability. To effectively control the societal impact of public opinion evolution, it is essential to study its underlying mechanisms. Public opinion evolution on social media primarily involves two processes: information dissemination and opinion interaction. However, existing studies overlook the bidirectional coupling relationship between these two processes, with limitations such as weak coupling and insufficient consideration of individual heterogeneity. To address this, we propose the SIS-FJ model with a bidirectional coupling mechanism, which combines the strengths of the SIS (Susceptible–Infected–Susceptible) model in information dissemination and the FJ (Friedkin–Johnsen) model in opinion interaction. Specifically, the SIS model is used to describe information dissemination, while the FJ model is used to describe opinion interaction. In the computation of infection and recovery rates of the SIS model, we introduce the opinion differences between individuals and their observable neighbors from the FJ model. In the computation of opinion values in the FJ model, we introduce the node states from the SIS model, thus achieving bidirectional coupling between the two models. Moreover, the model considers individual heterogeneity from multiple aspects, including infection rate, recovery rate, and individual susceptibility. Through simulation experiments, we investigate the effects of initial opinion distribution, individual susceptibility, and network structure on public opinion evolution. Interestingly, neither initial opinion distribution, individual susceptibility, nor network structure exerts a significant influence on the proportion of disseminating and non-disseminating individuals at termination. Furthermore, we optimize the model by adjusting the functions for infection and recovery rates
81 fJ/bit energy-to-data ratio of 850 nm vertical-cavity surface-emitting lasers for optical interconnects
This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Appl. Phys. Lett. 98, 231106 (2011) and may be found at https://doi.org/10.1063/1.3597799.Extremely energy-efficient oxide-confined high-speed 850 nm vertical-cavity surface-emitting lasers for optical interconnects are presented. Error-free performance at 17 and 25 Gb/s via a 100 m multimode fiber link is demonstrated at record high dissipation-power-efficiencies of up to 69 fJ/bit (<0.1mW/Gbps) and 99 fJ/bit, respectively. These are the most power efficient high-speed directly modulated light sources reported to date. The total energy-to-data ratio is 83 fJ/bit at 25°C and reduces to 81 fJ/bit at 55°C. These results were obtained without adjustment of driving conditions. A high -factor of 12.0GHz/(mA)0.5 and a -factor of 0.41 ns are measured.EC/FP7/224211/EU/VISIT - Vertically Integrated Systems for Information Transfer/VISITDFG, 43659573, SFB 787: Halbleiter - Nanophotonik: Materialien, Modelle, Bauelement
Dose-volume histograms (DVHs) of the large-field volumetric arc therapy (LF-VMAT) and fixed-jaw VMAT (FJ-VMAT) plans.
The solid line: the FJ-VMAT plans. The dotted line: the LF-VMAT plans.</p
Angiopoietin-like protein 1 expression is related to intermuscular connective tissue and cartilage development.
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