259 research outputs found
Evaluation of social personalized adaptive E-Learning environments : end-user point of view
The use of adaptations, along with the social aïŹordances of collaboration and networking, carries a great potential for improving e-learning experiences. However, the review of the previous work indicates current e-learning systems have only marginally explored the integration of social features and adaptation techniques. The overall aim of this research, therefore, is to address this gap by evaluating a system developed to foster social personalized adaptive e-learning experiences. We have developed our ïŹrst prototype system, Topolor, based on the concepts of Adaptive Educational Hypermedia and Social E-Learning. We have also conducted an experimental case study for the evaluation of the prototype system from diïŹerent perspectives. The results show a considerably high satisfaction of the end users. This paper reports the evaluation results from end user point of view, and generalizes our method to a component-based evaluation framework
End-to-End Learning of Video Super-Resolution with Motion Compensation
Learning approaches have shown great success in the task of super-resolving
an image given a low resolution input. Video super-resolution aims for
exploiting additionally the information from multiple images. Typically, the
images are related via optical flow and consecutive image warping. In this
paper, we provide an end-to-end video super-resolution network that, in
contrast to previous works, includes the estimation of optical flow in the
overall network architecture. We analyze the usage of optical flow for video
super-resolution and find that common off-the-shelf image warping does not
allow video super-resolution to benefit much from optical flow. We rather
propose an operation for motion compensation that performs warping from low to
high resolution directly. We show that with this network configuration, video
super-resolution can benefit from optical flow and we obtain state-of-the-art
results on the popular test sets. We also show that the processing of whole
images rather than independent patches is responsible for a large increase in
accuracy.Comment: Accepted to GCPR201
Motion Deblurring in the Wild
The task of image deblurring is a very ill-posed problem as both the image
and the blur are unknown. Moreover, when pictures are taken in the wild, this
task becomes even more challenging due to the blur varying spatially and the
occlusions between the object. Due to the complexity of the general image model
we propose a novel convolutional network architecture which directly generates
the sharp image.This network is built in three stages, and exploits the
benefits of pyramid schemes often used in blind deconvolution. One of the main
difficulties in training such a network is to design a suitable dataset. While
useful data can be obtained by synthetically blurring a collection of images,
more realistic data must be collected in the wild. To obtain such data we use a
high frame rate video camera and keep one frame as the sharp image and frame
average as the corresponding blurred image. We show that this realistic dataset
is key in achieving state-of-the-art performance and dealing with occlusions
The Effect of the Pairing Interaction on the Energies of Isobar Analog Resonances in Sb and Isospin Admixture in Sn Isotopes
In the present study, the effect of the pairing interaction and the isovector
correlation between nucleons on the properties of the isobar analog resonances
(IAR) in Sb isotopes and the isospin admixture in Sn
isotopes is investigated within the framework of the quasiparticle random phase
approximation (QRPA). The form of the interaction strength parameter is related
to the shell model potential by restoring the isotopic invariance of the
nuclear part of the total Hamiltonian. In this respect, the isospin admixtures
in the Sn isotopes are calculated, and the dependence of the
differential cross section and the volume integral for the
Sn(He,t)Sb reactions at E(He) MeV occurring by the excitation
of IAR on mass number A is examined. Our results show that the calculated value
for the isospin mixing in the Sn isotope is in good agreement with Colo
et al.'s estimates , and the obtained values for the volume integral
change within the error range of the value reported by Fujiwara et al.
(535 MeV fm). Moreover, it is concluded that although the
differential cross section of the isobar analog resonance for the (He,t)
reactions is not sensitive to pairing correlations between nucleons, a
considerable effect on the isospin admixtures in isotopes can be
seen with the presence of these correlations.Comment: 16 pages, 5 EPS figures and 2 tables, Late
Ascites as an initial presentation of spontaneously ruptured hydatid cyst
We describe the diagnosis of a 77-year-old woman admitted toour outpatient department with a 3-month history of abdominalbloating and distension. Abdominal computed tomographyrevealed a large cystic lesion in the posterior segment of the righthepatic lobe, with a separated germinal layer and widespreadascites with dense internal echoes and septal appearance. Theresult of a serum Echinococcus indirect haemagglutination testwas positive and findings were indicative of the spontaneousrupture of a hydatid cyst into the peritoneal cavity withouttrauma. Ascites is rarely seen in the course of hydatid disease,but can result from cyst rupture into the peritoneal cavity. Thisshould be considered in the differential diagnosis of ascites,especially in areas such as Turkey, where hydatid disease inendemic
A review of inorganic photoelectrode developments and reactor scale-up challenges for solar hydrogen production
Green hydrogen, produced using solar energy, is a promising means of reducing greenhouse gas emissions. Photoelectrochemical (PEC) water splitting devices can produce hydrogen using sunlight and integrate the distinct functions of photovoltaics and electrolyzers in a single device. There is flexibility in the degree of integration between these electrical and chemical energy generating components, and so a plethora of archetypal PEC device designs has emerged. Although some materials have effectively been ruled out for use in commercial PEC devices, many principles of material design and synthesis have been learned. Here, the fundamental requirements of PEC materials, the top performances of the most widely studied inorganic photoelectrode materials, and reactor structures reported for unassisted solar water splitting are revisited. The main phenomena limiting the performance of upâscaled PEC devices are discussed, showing that engineering must be considered in parallel with material development for the future piloting of PEC water splitting systems. To establish the future commercial viability of this technology, more accurate technoâeconomic analyses should be carried out using data from larger scale demonstrations, and hence more durable and efficient PEC systems need to be developed that meet the challenges imposed from both material and engineering perspectives
Sizing solar-based mini-grids for growing electricity demand: insights from rural India
Mini-grids are a critical way to meet electricity access goals according to current and projected electricity demand of communities and so appropriately sizing them is essential to ensure their financial viability. However, estimation of demand for communities awaiting electricity access is uncertain and growth in demand along with the associated cost implications is rarely considered during estimation of mini-grid sizing. Using a case study of two rural communities in India, we assess the implications of demand growth on financial costs and performance of a mini-grid system consisting of solar photovoltaic (PV) panels and battery storage using two different system sizing approaches. We show a cost-saving potential of up to 12% when mini-grids are sized using a multi-stage approach where mini-grids gradually expand in several stages, rather than a single-stage optimisation approach. We perform a sensitivity analysis of the cost of the two sizing approaches by varying six key parameters: demand growth rate, logistics cost, system re-sizing frequency, likelihood of blackouts, solar PV and battery cost, and degradation rate. Of these, we find that system costs are most sensitive to variations in demand growth rates and cost decreases in solar PV and batteries. Our study shows that demand growth scenarios and choice of mini-grid sizing approaches have important financial and operational implications for the design of systems for rural electrification
RAMCESS 2.X framework - expressive voice analysis for realtime and accurate synthesis of singing
peer reviewedIn this paper we present the work that has been achieved in the context of the second version of the Ramcess singing synthesis framework. The main improvement of this study is the integration of new algorithms for expressive voice analysis, especially the separation of the glottal source and the vocal tract. Realtime synthesis modules have also been refined. These elements have been integrated in an existing digital instrument: the HandSketch 1.x, a bi-manual controller. Moreover this digital instrument is compared to existing systems
Simple, Accurate, and Robust Nonparametric Blind Super-Resolution
This paper proposes a simple, accurate, and robust approach to single image
nonparametric blind Super-Resolution (SR). This task is formulated as a
functional to be minimized with respect to both an intermediate super-resolved
image and a nonparametric blur-kernel. The proposed approach includes a
convolution consistency constraint which uses a non-blind learning-based SR
result to better guide the estimation process. Another key component is the
unnatural bi-l0-l2-norm regularization imposed on the super-resolved, sharp
image and the blur-kernel, which is shown to be quite beneficial for estimating
the blur-kernel accurately. The numerical optimization is implemented by
coupling the splitting augmented Lagrangian and the conjugate gradient (CG).
Using the pre-estimated blur-kernel, we finally reconstruct the SR image by a
very simple non-blind SR method that uses a natural image prior. The proposed
approach is demonstrated to achieve better performance than the recent method
by Michaeli and Irani [2] in both terms of the kernel estimation accuracy and
image SR quality
- âŠ