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991.
Chin Lay Gan Vimala Balakrishnan 《International journal of human-computer interaction》2018,34(7):666-679
Online learning when combined with mobile technology transforms the traditional classrooms from teacher-centered to student-centered classrooms. Despite the widespread use of mobile technology among students and educators today, limited researches have been conducted to study the effects of using mobile technology to enhance student–lecturer interactions. In addition, existing theories of technology acceptances, chiefly Information System Success Model (ISSM), Motivational Model (MM), Social Cognitive Theory (SCT), Technology Acceptance Model (TAM), and Cultural Dimension Theory (CDT) are widely recognized for their predictive power in determining adoption intentions. In this study, determinants from all five theories were unified and examined, namely system quality and information quality from ISSM, enjoyment from MM, perceived usefulness and perceived ease of use from TAM, self-efficacy from SCT, and uncertainty avoidance from CDT as predictors of adoption intention in the context of predicting student–lecturer interactions. This empirical study was conducted using an online survey. Data collected from the samples (n = 328) were analyzed using PLS-SEM. Results obtained exhibited adequate explanatory power, where information quality, system quality, enjoyment, and uncertainty avoidance significantly predict adoption intention, while perceived usefulness, perceived ease of use, and self-efficacy were insignificant. Secondly, each theory was independently analyzed, and the predictive power and relevance of ISSM, MM, TAM, and UDT confirmed the importance and relevance of these theories. Results obtained provided a comprehensive understanding of the factors that significantly affect students’ intentions to use mobile technology to interact with their lecturers on academic matters. The discussions and implications of this study are crucial for researchers and practitioners of educational technologies in higher education. 相似文献
992.
Yung‐Chun Chang Pi‐Hua Chuang Chien Chin Chen Wen‐Lian Hsu 《Computational Intelligence》2017,33(4):656-679
Discovering the interactions between the persons mentioned in a set of topic documents can help readers construct the background of the topic and facilitate document comprehension. To discover person interactions, we need a detection method that can identify text segments containing information about the interactions. Information extraction algorithms then analyze the segments to extract interaction tuples and construct a network of person interaction. In this article, we define interaction detection as a classification problem. The proposed interaction detection method, called feature‐based interactive segment recognizer (FISER), exploits 19 features covering syntactic, context‐dependent, and semantic information in text to detect intra‐clausal and inter‐clausal interactive segments in topic documents. Empirical evaluations demonstrate that FISER outperformed many well‐known relation extraction and protein–protein interaction detection methods on identifying interactive segments in topic documents. In addition, the precision, recall, and F1‐score of the best feature combination are 72.9%, 55.8%, and 63.2%, respectively. 相似文献
993.
Modeling crack discontinuities without element‐partitioning in the extended finite element method
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E. B. Chin J. B. Lasserre N. Sukumar 《International journal for numerical methods in engineering》2017,110(11):1021-1048
In this paper, we model crack discontinuities in two‐dimensional linear elastic continua using the extended finite element method without the need to partition an enriched element into a collection of triangles or quadrilaterals. For crack modeling in the extended finite element, the standard finite element approximation is enriched with a discontinuous function and the near‐tip crack functions. Each element that is fully cut by the crack is decomposed into two simple (convex or nonconvex) polygons, whereas the element that contains the crack tip is treated as a nonconvex polygon. On using Euler's homogeneous function theorem and Stokes's theorem to numerically integrate homogeneous functions on convex and nonconvex polygons, the exact contributions to the stiffness matrix from discontinuous enriched basis functions are computed. For contributions to the stiffness matrix from weakly singular integrals (because of enrichment with asymptotic crack‐tip functions), we only require a one‐dimensional quadrature rule along the edges of a polygon. Hence, neither element‐partitioning on either side of the crack discontinuity nor use of any cubature rule within an enriched element are needed. Structured finite element meshes consisting of rectangular elements, as well as unstructured triangular meshes, are used. We demonstrate the flexibility of the approach and its excellent accuracy in stress intensity factor computations for two‐dimensional crack problems. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
994.
J. V. Pearce A. D. Greenen A. Smith C. J. Elliott 《International Journal of Thermophysics》2017,38(2):26
A simple model is presented which relates the electromotive force drift rate of Pt–Rh thermoelements to dS/dc, the sensitivity of the Seebeck coefficient, S, to rhodium mass fraction, c. The model has been tested by repeated measurements of a Pt–Rh thermocouple assembly consisting of five thermoelements, using a Co-C high-temperature fixed point (\(1324{\,}^{\circ }{\mathrm{C}}\)) for a total duration of 500 h. By considering various thermocouples from the assembly, it is demonstrated that in this case, remarkably, there is a linear relationship between the measured drift rate and the combined dS/dc, where the combination is determined by addition of the individual values for each wire. Particular emphasis is placed on evaluation of the uncertainties associated with the calculations. This result supports previous findings that the thermoelectric stability of Pt–Rh thermoelements improves as the rhodium mass fraction increases. Within this paradigm, it is shown that for a selected Pt–Rh thermoelement of any given composition, there exists a second thermoelement having a composition that yields a minimum drift when combined with the first to form a thermocouple. 相似文献
995.
Dorothy Caminos-Peruelo Wei-Chieh Wang Tsung-Shune Chin Regina C So Ronaldo M Fabicon Ming-Fa Hsieh 《Bulletin of Materials Science》2017,40(6):1179-1187
Preparation and characterization of a low-cost, novel steam-activated bamboo charcoal (BC) and poly(methacrylate) (PMAA) bound with chitosan (CTS) to form chitosan/bamboo charcoal/poly(methacrylate) (CTS/BC/PMAA) composite beads is reported for the first time in this paper. The characteristics are revealed by techniques such as X-ray photoelectron spectroscopy (XPS), thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC), scanning electron microscopy (SEM), Brunauer Emmett Teller (BET), solution pH and pH at point of zero charge \((\hbox {pH}_{\mathrm {pzc}})\). The composite beads possessed a dominant acidic surface group of 0.663 mmol \(\hbox {g}^{\mathrm {-1}}\), as revealed by Boehm titration method. This acidity was confirmed by its solution pH of 6.46; \(\hbox {pH}_{\mathrm {pzc}}\) of 6.70 and increase in oxygen surface via XPS analysis. \(\hbox {N}_{\mathrm {2}}\) adsorption–desorption isotherms at 77 K of the beads revealed high BET surface area (SA) of 681.15 \(\hbox {m}^{\mathrm {2}}\hbox {g}^{\mathrm {-1}}\). Langmuir model affords a SA of 773.34 \(\hbox {m}^{\mathrm {2}}\hbox {g}^{\mathrm {-1}}\). SEM showed the microporous nature of the composite beads. The properties of CTS/BC/PMAA composite beads were compared to CTS/BC and neat BC. Thermal stability and successful coating of 5.1 wt% of PMAA and 6.8 wt% of CTS to CTS/BC/PMAA beads were shown by DSC and TGA analyses. The composite beads showed low carbon particle released at pH 7.4 and 6.8. Furthermore, dynamic adsorption revealed that CTS/BC/PMAA composite beads can be used to capture a polar substance, such as creatinine. 相似文献
996.
Bamidele V. Ayodele Maksudur R. Khan Safdar Sk Nooruddin Chin Kui Cheng 《Clean Technologies and Environmental Policy》2017,19(4):1181-1193
The reforming of methane by carbon dioxide for the production of syngas is a potential technological route for the mitigation of greenhouse gases. However, the process is highly endothermic and often accompanied by catalyst deactivation from sintering and carbon deposition. Besides, the applications of dissimilar catalytic systems in methane dry reforming have made it difficult to obtain generalized optimum conditions for the desired products. Hence, optimization studies of any catalytic system often resulted in a unique optimum condition. The present study aimed to investigate optimum conditions of variables such as methane (CH4) partial pressure, carbon dioxide (CO2) partial pressure and reaction temperature that will maximize syngas yields from methane dry reforming over samarium oxide supported cobalt (Co/Sm2O3) catalyst. The Co/Sm2O3 catalyst was synthesized using wet-impregnation method and characterized by thermogravimetric analysis), field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray powder diffraction and nitrogen (N2) physisorption. Syngas production by methane dry reforming over the synthesized Co/Sm2O3 catalyst was investigated in a stainless steel fixed-bed reactor. The process variables (CH4 partial pressure, CO2 partial pressure and reaction temperature) for the syngas production were optimized using response surface methodology (RSM). The RSM and artificial neural networks (ANNs) were used to predict the syngas production from the experimental data. The comparative analysis between the two models showed that the ANN model has better prediction of the syngas yields compared to the RSM model as evident from the good agreement between the observed and the predicted values. At maximum desirability value of 0.97, optimum CH4 and CO2 partial pressures of 47.9 and 48.9 kPa were obtained at reaction temperature of 735 °C resulting in syngas yield of ~79.4 and 79.0% for hydrogen (H2) and carbon monoxide (CO), respectively. 相似文献
997.
A Metal–Insulator Transition of the Buried MnO2 Monolayer in Complex Oxide Heterostructure
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Heng‐Jui Liu Jheng‐Cyuan Lin Yue‐Wen Fang Jing‐Ching Wang Bo‐Chao Huang Xiang Gao Rong Huang Philip R. Dean Peter D. Hatton Yi‐Ying Chin Hong‐Ji Lin Chien‐Te Chen Yuichi Ikuhara Ya‐Ping Chiu Chia‐Seng Chang Chun‐Gang Duan Qing He Ying‐Hao Chu 《Advanced materials (Deerfield Beach, Fla.)》2016,28(41):9142-9151
998.
Ting‐Hao Lin Der‐Lor Way Zen‐Chung Shih Wen‐Kai Tai Chin‐Chen Chang 《Computer Graphics Forum》2016,35(7):57-66
Photos contain well‐structured and plentiful visual information. Edges are active and expressive stimuli for human visual perception. However, it is hard to separate structure from details because edge strength and object scale are entirely different concepts. This paper proposes a structure‐aware bilateral texture algorithm to remove texture patterns and preserve structures. Our proposed method is simple and fast, as well as effective in removing textures. Instead of patch shift, smaller patches represent pixels located at structure edges, and original patches represent the texture regions. Specifically, this paper also improves joint bilateral filter to preserve small structures. Moreover, a windowed inherent variation is adapted to distinguish textures and structures for detecting structure edges. Finally, the proposed method produces excellent experimental results. These results are compared to some results of previous studies. Besides, structure‐preserving filtering is a critical operation in many image processing applications. Our proposed filter is also demonstrated in many attractive applications, such as seam carving, detail enhancement, artistic rendering, etc. 相似文献
999.
The fundamental approach to improve pilots’ situation awareness (SA) would be to reorganize and restructure the presentation of information to fit pilot's cognitive model on the flight deck. This would facilitate pilots’ perception, understanding, and projection, hence making it easier to find the relevant targets. Sixty pilots (30 B‐737 pilots and 30 B‐777 pilots) participated in this study to investigate pilots’ SA while interacting with digital displays and moving pointed needle displays on cabin pressurization system. The results have shown significant differences on pilots’ perception, understanding, and overall SA between digital display and pointed display on the flight deck. Pilots significantly preferred the digital design cabin pressurization system, which is consistent with the proximity compatibility principle, and the position of the display on the center instrument panel is easily accessible to both pilots and does not require large head movements. There are some recommendations on the cabin pressurization design including the size of outflow valve position indicator, which should be significantly increased to provided saliency of information; color coding should be used on cabin altitude and differential pressure indicator to mark critical cabin altitude; and standard operating procedures shall include cabin altitude and differential pressure reading by pilot monitoring. The final and completed solution to the issues on the cabin pressurization system is to redesign the scattered pointed displays as integrated digital displays to fit the human‐centered principle. 相似文献
1000.
Chi‐Hui Chien Chun‐Cheng Chen Thaiping Chen Yu‐Min Lin Yuan‐Chin Liu 《Journal of the Society for Information Display》2016,24(2):99-109
Thermal deformations of a microstructure diffuser plate in an LED backlight unit subjected to a long period of illumination were studied. Mechanical properties of the microstructure diffuser plate in the LED backlight unit were determined and verified. Rather than using data from the relevant literature, accurate finite element solutions were obtained by using a microtensile test and thermo‐mechanical analyzer to calculate the Young's modulus, Poisson's ratio, and thermal expansion coefficient of the microstructure diffuser plate. The measured mechanical properties were used as input data in finite element simulations. Comparisons of the finite element analysis results with the experimental measurements made using strain gauge yielded differences of less than 3%. Thermal warpage phenomena of the microstructure diffuser plate at various temperatures are discussed. Thermal deformations are also compared between the conventional diffuser plate and the microstructure diffuser plate. 相似文献