Search results for "processing"
showing 10 items of 8572 documents
Predicting human performance in interactive tasks by using dynamic models
2017
The selection of an appropriate sequence of activities is an essential task to keep student motivation and foster engagement. Usually, decisions in this respect are made by taking into account the difficulty of the activities, in relation to the student's level of competence. In this paper, we present a dynamic model that aims to predict the average performance of a group of students at solving a given series of maths problems. The system takes into account both student- and task-related features. This model was built and validated by using the data gathered in an experimental session that involved 64 participants solving a sequence of 26 arithmetic problems. The data collected from the fir…
2020
To successfully learn using open Internet resources, students must be able to critically search, evaluate and select online information, and verify sources. Defined as critical online reasoning (COR), this construct is operationalized on two levels in our study: (1) the student level using the newly developed Critical Online Reasoning Assessment (CORA), and (2) the online information processing level using event log data, including gaze durations and fixations. The written responses of 32 students for one CORA task were scored by three independent raters. The resulting score was operationalized as “task performance,” whereas the gaze fixations and durations were defined as indicators of “pr…
On the harvest of rainfall energy by means of piezoelectric transducer
2013
In this paper a detailed study on the harvest of the energy contained in rainfall by means of piezoelectric transducers is presented. Diverse studies agree on the level of suitable generated voltage on the electrodes of a piezoelectric transducer subjected to rainfall, but a complete characterization on the supplied power is still missing. This work, in order to limit optimistic forecasts, takes into account the behavior of the transducers subjected to real and also artificial rainfall, condition that has shown promising behavior in laboratory. In order to increase the energy harvesting and also define its limits different loads have been taken into account. Only commercial transducers have…
Internet and computer game addiction - a review of current neuroscientific research
2011
IntroductionA significant part computer game players and internet users show clinical features of abuse and addiction (loss of control, withdrawal symptoms, tolerance, continuation of game play even with increasing negative consequence in social and academic life). Similar mechanisms are suggested to underlie the pathogenesis and maintenance of internet and computer game addiction and substance-related addictions.ObjectivesNeuroscientific research on internet and computer game addiction is sparse, yet emerging. To review previous studies is the objective of the present project.AimsWe aim to identify common findings regarding the neurophysiological processes underlying internet and computer …
On the use of generalized harmonic means in image processing using multiresolution algorithms
2019
In this paper we design a family of cell-average nonlinear prediction operators that make use of the generalized harmonic means and we apply the resulting schemes to image processing. The new famil...
Pattern languages with and without erasing
1994
The paper deals with the problems related to finding a pattern common to all words in a given set. We restrict our attention to patterns expressible by the use of variables ranging over words. Two essentially different cases result, depending on whether or not the empty word belongs to the range. We investigate equivalence and inclusion problems, patterns descriptive for a set, as well as some complexity issues. The inclusion problem between two pattern languages turns out to be of fundamental theoretical importance because many problems in the classical combinatorics of words can be reduced to it.
Use of a new aneurysm clip with an inverted-spring mechanism to facilitate visual control during clip application. Technical note.
1995
✓ When operating on deep-seated cerebral aneurysms, the surgeon's visual control of clip application may be impaired by the clip holder unless adjacent structures are retracted. To improve visual control and reduce the necessity for retraction, the senior author (A.P.) developed a new concept: an aneurysm clip with an inverted-spring mechanism. The clip has two jaws that point away from the clip blades. The jaws of the clip holder articulate with the inner side of the clip jaws. By distending the jaws of the clip holder the blades of the clip are opened and vice versa. Thus the visual field increases while the clip application is proceeding. This instrumentation is useful, especially in cas…
Ensemble feature selection with the simple Bayesian classification
2003
Abstract A popular method for creating an accurate classifier from a set of training data is to build several classifiers, and then to combine their predictions. The ensembles of simple Bayesian classifiers have traditionally not been a focus of research. One way to generate an ensemble of accurate and diverse simple Bayesian classifiers is to use different feature subsets generated with the random subspace method. In this case, the ensemble consists of multiple classifiers constructed by randomly selecting feature subsets, that is, classifiers constructed in randomly chosen subspaces. In this paper, we present an algorithm for building ensembles of simple Bayesian classifiers in random sub…
Parallel distance transforms on pyramid machines: Theory and implementation
1990
Abstract A distance transform of a binary image is an array each of whose elements gives the distance from the corresponding pixel to the closest ‘1’ in the binary image. Distance transforms have uses in image matching and shape analysis, among other applications. We present a parallel algorithm for weighted distance transforms that runs particularly efficiently on hierarchical cellular-logic machines, a subclass of the architectures known as pyramid machines. The algorithm computes the 3–4 distance transform; however it can be readily adapted to the city-block (‘Manhattan’) and chessboard distance measures. The algorithm runs in O(M) time, for an M × M image. Since it avoids using arithmet…
Detecting motion independent of the camera movement through a log-polar differential approach
1997
This paper is concerned with a differential motion detection technique in log-polar coordinates which allows object motion tracking independently of the camera ego-motion when camera focus is along the movement direction. The method does not use any explicit estimation of the motion field, which can be calculated afterwards at the moving points. The method, previously formulated in Cartesian coordinates, uses the log-polar coordinates, which allows the isolation of the object movement from the image displacement due to certain camera motions. Experimental results on a sequence of real images are included, in which a moving object is detected and optical flow is calculated in log-polar coord…