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We present the M.In.E.R.Va. project, an online tool to help students (both attending Secondary Schools and Universities) recovering their deficiencies in Mathematics. We also present an analysis of the answers given by the students, performed using the Rasch model, which allows to investigate both students' results and the validity of the items.
For a directed graph and two vertices, to check whether there is a path between them is so-called reach ability query, how to establish efficient index to answer the reach ability of two nodes has always been a research direction in the field of database. In this paper, we proposed a reach ability query approach combining the concept of path dividing and interval labeling. We establish an index with...
Link prediction is a basic problem in the research of social networks. At present, most link prediction algorithms are based on the features extracted from network structure, few research concerns the effect of natural attributes of nodes for creating a link. In this paper we develop a novel way to predict links based on Random Walk algorithm using the information from both the network topology and...
The Lambert W function possesses branches labelled by an index k. The value of W therefore depends upon the value of its argument z and the value of its branch index. Given two branches, labelled n and m, the branch difference is the difference between the two branches, when both are evaluated at the same argument z. It is shown that elementary inverse functions have trivial branch differences, but...
The data placement issues in cloud computing platform have been extensively researched, mainly in the choice of the number of data replica, initial data placement strategy, the run-time and dynamically adjustment and routing algorithm and other aspects of the transaction request. In this paper, we design a whole framework to the method of placing data replica for analysis and description from a higher...
The existing research of distributed provenance storage is at the preliminary stage. Most of the researchers are endeavor to improve the query efficiency of storage solution, whereas, very few people pay attention to the matching problem of provenance and data and the waste of storage space. Two aspects on the problem of provenance storage were proposed in this paper. First one is the relationship...
Variety in Big Data means we have a wide range of data types and sources: e.g. File systems and database systems co-exist for decades as two popular data-accessing interfaces. This work is to unify these two interfaces by presenting a Data Interface All-iN-A-place (DIANA). The first challenge lies in distinguishing structured and un-structured data and diverting them to different underlying platforms...
WLANs (Wireless Local Area Networks) are widely used for Internet access. But the WLANs in locations such as airports and large conventions usually suffer poor performance in terms of downlink TCP (Transmission Control Protocol) throughput To alleviate these problems, we propose an AFCP (Adaptive Flow Control Proxy) approach, which acts like a TCP Proxy and monitors the traffic flowing through the...
With the prosperity of the Open Source Software, various software communities are formed and they attract huge amounts of developers to participate in distributed software development. For such software development paradigm, how to evaluate the skills of the developers comprehensively and automatically is critical. However, most of the existing researches assess the developers based on the Implementation...
In this paper, the radial pulse waveforms of the same subjects under various contact pressures were measured. Then, the feature points of the pulse wave contours were extracted and the physical parameters were calculated corresponding to different contact pressures. The various trends of parameters, including peripheral augmentation index, peripheral subendocardial viability ratio, and peripheral...
This work investigates phase synchrony as a neuro-marker for the identification of two brain states: coma and quasi-brain-death. Scalp electroencephalography (EEG) data of 34 patients were recorded in an intensive care unit (ICU), with 17 recordings for patients in a coma state, and 17 recordings for patients in a quasi-brain-death state. Phase synchrony was used for feature extraction from EEG recording...
In clinical practice, cognitive impairment is often observed after stroke. The efficacy of rehabilitative interventions is routinely assessed by means of a neuropsychological test battery. Nowadays, more evidences indicate that the neuroplasticity which occurs after stroke can be better understood by investigating changes in brain networks. In this study we applied advanced methodologies for effective...
Skyline queries are useful in decision making applications. Skyline queries in highly mobile distributed environments have attracted many attentions recently due to the development of mobile internet device. The properties of distributed computing make skyline queries more complicated especially in any subspace. Conventional skyline algorithms do not support subspace skyline queries in distributed...
This paper presents an automatic stress-relieving music recommendation system (ASMRS) for individual music listeners. The ASMRS uses a portable, wireless photoplethysmography module with a finger-type sensor, and a program that translates heartbeat signals from the sensor to the stress index. The sympathovagal balance index (SVI) was calculated from heart rate variability to assess the user's stress...
This study examined characteristics of the brain networks related to upper limb grasp movements. EEG signal of 4 patients with chronic stroke were analyzed during different motor tasks. We compared the brain networks involved in the Active and Motor Imagery tasks by using the centrality and small-worldness (SW). There was a statistically significant difference between the centralities of two motor...
High dimensional functional MRI data in combination with a low temporal resolution imposes computational limits on classical Granger Causality analyses with respect to a large-scale representations of functional interactions in the brain. To overcome these limitations and exploit information inherent in resulting brain connectivity networks at the large scale, we propose a multivariate Granger Causality...
A new physiological index (μPA) is proposed to represent the autonomic nervous system (ANS) function. The index μPA is defined as the natural logarithm of the ratio between two different frequency components of the pulsatile amplitude of the photoplethysmogram (PPG) signal. The discrimination ability and the reproducibility of μPA have been compared with other traditional ANS indices. In the experiment,...
A new approach to denoise chaotic signals based on ensemble empirical mode decomposition (EEMD) is proposed. The EEMD technique is first used to decompose the noisy chaotic signal into the so-called intrinsic mode functions (IMFs). A criterion is proposed to determine which modes are used to reconstruct the denoised signal. Computer simulations are used to demonstrate the effect of the method. The...
The purpose of poverty declaration and evaluation of university students is to help the poor students to overcome economic difficulties, and to provide security for their normal life and learning. In this paper, we use the fuzzy comprehensive evaluation method to build a poverty evaluation model of university students. We combine the actual situation and questionnaire of a real university firstly,...
Concept maps can help students learn more meaningfully. According to test scores only, students were divided into three groups of high-score, middle-score and low-score, in the previous works, researchers then applied data mining association rule technique to analysis different student groups' assessment data to construct corresponding concept maps. However, for considering more accurate to evaluate...
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