1,291 research outputs found

    Factors Influencing Learning Intention of Advanced Placement MOOCs: Insights from an Investigation into Information Technology Adoption

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    Massive open online courses (MOOCs) have attracted recent scholarly attention, mainly because MOOCs have effectively made higher education accessible. However, MOOCs tend to have low completion rates, and many scholars have attempted to remedy this by investigating the psychological, cognitive, physiological, and demographic factors affecting completion rates. Nevertheless, most studies have rarely investigated the student’s information technology (IT) background, focusing instead on self-awareness, self-recognition, intrinsic motivation, or external factors. Thus, this study adopted the technology acceptance model (TAM) to explore factors affecting MOOC learning intention, specifically in advanced placement (AP) MOOCs. This study also recruited 435 student participants from a university in Taiwan who took MOOCs for AP. Questionnaires were used to analyze the factors affecting completion rates. The results revealed that personal and IT backgrounds significantly affected perceived ease of use (PEU); perceived usefulness (PU) significantly affected attitude toward use (ATU); PEU significantly affected ATU; PEU significantly affected PU; ATU significantly affected behavioral intention to use (BITU); PU significantly affected BITU; and BITU significantly affected course completion rates. The results suggest that universities first understand students’ personal and IT backgrounds before promoting their AP MOOCs, as this can assist students in their learning and provide the necessary support. . Furthermore, universities must also establish a complete course-provision process and formulate learning strategies to attract, guide, and inspire students to adapt to the learning modes that AP MOOCs entail. In doing so, students are more likely to perceive MOOC learning modes as being innovative and thus learn more effectively

    Site Effect Evaluation Using Combination of Source Scaling Models and Ground Motion Records

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    We analyze site response of the Taipei basin using the records obtained by the Taiwan Strong Ground Motion Instrumentation Program (TSMIP) network. Records of 66 earthquakes of M=2.6-6.5 with a hypocentral depth varying from 1 km to 118 km and hypocentral distances of up to 150 km are studied for 35 stations located within this triangle shaped alluvium structure. The site response is obtained in terms of spectral ratios calculated by dividing of the site spectrum by the reference spectrum estimated for a hypothetical “very hard rock” site. The recently developed empirical source scaling and attenuation models are used for the reference spectra calculation. This approach allows us to evaluate the variability of spectral ratios due to uncertainties introduced by source and propagation path effects and variability in the site response itself. The characteristics of site response in the Taipei basin depend on the properties of soil deposits and, in general, may be described by I-D models. However, there are some peculiarities of spectral ratios that show the influence of subsurface topography

    Probabilistic Microzonation of Urban Territories: A Case of the Taipei City

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    An integrated approach for evaluating “site-dependent” seismic hazard in terms of ground-motion parameters, which are used for engineering purposes, is presented. The method is based on the probabilistic seismic hazard analysis in terms of Fourier acceleration spectra. A scheme that allows conversion of the Uniform Hazard Fourier spectra to “hazard-compatible” peak ground acceleration (PGA), and Uniform Hazard response spectra is described. The method has been applied for preliminary probabilistic microzonation of the Taipei basin (the Taipei city). The source, path and site effects are characterized separately on the basis of the analysis of large collection of ground-motion recordings obtained since 1991 in Taiwan area. The probabilistic microzonation maps of the Taipei basin were compiled for various return periods and were compared with the data from recent strong earthquakes. It has been shown that Peak Ground Acceleration and amplitudes of the Uniform Hazard Response spectra strictly depend both on the local site conditions and on the characteristics of seismicity (the depth and location of earthquakes, and azimuthal direction of incident excitation). Therefore, one single building code is not adequate for the whole basin area. The obtained “Region & Site & Return period-dependent” estimations may be used as a reliable basis for building code provisions and engineering decisions

    Spatial and Temporal Distribution of Trace Metals (Cd, Cu, Ni, Pb, and Zn) in Coastal Waters off the West Coast of Taiwan

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    Surface water samples were collected along the west coast of Taiwan during two expedition cruises which represent periods of different regional climatic patterns. Information on hydrochemical parameters such as salinity, nutrients, suspended particulate matter (SPM), and Chlorophyll a concentrations were obtained, and dissolved and particulate trace metal (Cd, Cu, Ni, Pb, and Zn) concentrations were determined. Spatial variations were observed and the differences were attributed to (1) influence of varying extents of terrestrial inputs from the mountainous rivers of Taiwan to the coast, and (2) urbanization and industrialization in different parts of the island. Geochemical processes such as desorption (Cd) and adsorption to sinking particles (Pb) also contributed to the variability of trace metal distributions in coastal waters. Results showed temporal variations in chemical characteristics in coastal waters as a consequence of prevailing monsoons. During the wet season when river discharges were higher, the transport of particulate metals was elevated due to increased sediment loads. During the dry season, lower river discharges resulted in a lesser extent of estuarine dilution effect for chemicals of anthropogenic sources, indicated by higher dissolved concentrations present in coastal waters associated with slightly higher salinity

    Load-balanced parallel banded-system solvers

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    AbstractSolving banded systems is important in the applications of science and engineering. This paper presents a load-balancing strategy for solving banded systems in parallel when the number of processors used is small. An optimization-based load-balancing analysis is given to determine how many loads should be assigned to each processor in order to minimize the time requirement. Some experimentations are carried out on the nCUBE 2E multiprocessor to demonstrate the speedup advantage of the proposed load-balancing strategy. The speedup improvement ratio ranges from 47% to 66% (from 12% to 24%) when using 4 (8) processors

    Effects of natto extract on endothelial injury in a rat model

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    Vascular endothelial damage has been found to be associated with thrombus formation, which is considered to be a risk factor for cardiovascular disease. A diet of natto leads to a low prevalence of cardiovascular disease. The aim of the present study was to investigate the effects of natto extract on vascular endothelia damage with exposure to laser irradiation. Endothelial damage both in vitro and in vivo was induced by irradiation of rose bengal using a DPSS green laser. Cell viability was determined by MTS assay, and the intimal thickening was verified by a histological approach. The antioxidant content of natto extract was determined for the free radical scavenging activity. Endothelial cells were injured in the presence of rose bengal irradiated in a dose-dependent manner. Natto extract exhibits high levels of antioxidant activity compared with purified natto kinase. Apoptosis of laser-injured endothelial cells was significantly reduced in the presence of natto extract. Both the natto extract and natto kinase suppressed intimal thickening in rats with endothelial injury. The present findings suggest that natto extract suppresses vessel thickening as a synergic effect attributed to its antioxidant and anti-apoptosis properties

    Inhibitory Effects of Ethyl Acetate Extract of Andrographis paniculata on NF-κB Trans-Activation Activity and LPS-Induced Acute Inflammation in Mice

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    This study was to investigate anti-inflammatory effect of Andrographis paniculata (Burm. f.) Nees (Acanthaceae) (AP). The effects of ethyl acetate (EtOAc) extract from AP on the level of inflammatory mediators were examined first using nuclear factor kappa B (NF-κB) driven luciferase assay. The results showed that AP significantly inhibited NF-κB luciferase activity and tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), macrophage inflammatory protein-2 (MIP-2) and nitric oxide (NO) secretions from lipopolysaccharide (LPS)/interferon-γ stimulated Raw264.7 cells. To further evaluate the anti-inflammatory effects of AP in vivo, BALB/c mice were tube-fed with 0.78 (AP1), 1.56 (AP2), 3.12 (AP3) and 6.25 (AP4) mg kg−1 body weight (BW)/day in soybean oil, while the control and PDTC (pyrrolidine dithiocarbamate, an anti-inflammatory agent) groups were tube-fed with soybean oil only. After 1 week of tube-feeding, the PDTC group was injected with 50 mg kg−1 BW PDTC and 1 h later, all of the mice were injected with 15 mg kg−1 BW LPS. The results showed that the AP1, AP2, AP3 and PDTC groups, but not AP4, had significantly higher survival rate than the control group. Thus, the control, AP1, AP2, AP3 and PDTC groups were repeated for in vivo parameters. The results showed that the AP and PDTC groups had significantly lower TNF-α, IL-12p40, MIP-2 or NO in serum or peritoneal macrophages and infiltration of inflammatory cells into the lung of mice. The AP1 group also had significantly lower MIP-2 mRNA expression in brain. This study suggests that AP can inhibit the production of inflammatory mediators and alleviate acute hazards at its optimal dosages

    Site classification and Vs30 estimation of free-field TSMIP stations using the logging data of EGDT

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    The Engineering Geological Database for TSMIP (EGDT), the Taiwan Strong Motion Instrumentation Program, has been under construction by the National Center for Research on Earthquake Engineering and the Central Weather Bureau in Taiwan since 2000. Site characterization, comprising surface investigations and logging measurements, was carried out throughout the project. We provide a set of specifications and a description to help users understand the subject matter of the database. EGDT contains 469 surveyed stations, 439 of which were drilled and the logging measurements completed. Of these, 385 had logging data reaching at least 30 m, and we used these to examine and determine the most accurate extrapolation of Vs30 (the average S-wave velocity of the top 30 m of strata) for the other 54 stations with velocity profiles less than 30 m. The chosen method assumed that the bottom velocity is identical from the actual depth of the hole to a distance of 30 m, that is, the Bottom Constant Velocity (BCV) method. In order to utilize other existing boreholes which have only N values but no velocities in the future, the empirical S-wave velocity equations for seven different regions and the whole of Taiwan were evaluated by a multivariable analysis. Henceforth, for those existing boreholes which have an N profile less than 30 m, the S-wave velocity profile can first be calculated by empirical S-wave velocity equations, and then Vs30 can be estimated by reliable extrapolation. Some other studies of site classifications of TSMIP stations were compared with our results to demonstrate the necessity of reclassification. Ultimately, the Vs30 values of the 439 drilled free-field TSMIP stations were derived and the new site classification was achieved according to the Vs30-based provisions of the National Earthquake Hazards Reduction Program
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