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1.
In this work, we present the first quality flaw prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove). Based on the underlying characteristics of each flaw, different state-of-the-art approaches were evaluated. For articles not citing any references, a well-established rule-based approach was evaluated and interesting findings show that some of them suffer from Refimprove flaw instead. Likewise, for articles that need additional citations for verification, the well-known PU learning and one-class classification approaches were evaluated. Besides, new methods were compared and a new feature was also proposed to model this latter flaw. The results showed that new methods such as under-bagged decision trees with sum or majority voting rules, biased-SVM, and centroid-based balanced SVM, perform best in comparison with the ones previously published.  相似文献   
2.
ABSTRACT

Moving beyond the dominant bag-of-words approach to sentiment analysis we introduce an alternative procedure based on distributed word embeddings. The strength of word embeddings is the ability to capture similarities in word meaning. We use word embeddings as part of a supervised machine learning procedure which estimates levels of negativity in parliamentary speeches. The procedure’s accuracy is evaluated with crowdcoded training sentences; its external validity through a study of patterns of negativity in Austrian parliamentary speeches. The results show the potential of the word embeddings approach for sentiment analysis in the social sciences.  相似文献   
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Peer and near-peer teaching programs are common in medical undergraduate courses. However, there are no studies that have investigated the effectiveness of a near-peer teaching program on the academic performance of undergraduate students pursuing sport and exercise science coursework. This study was conducted to analyze the effectiveness of such a program for students who participated in a course on the functional anatomy of the locomotor apparatus. A total of 39 student participants were divided into two groups: students in one group voluntarily attended at least one session of a near-peer teaching program, and students in the other group attended no sessions. The final grade (range 0–100%) was recorded and used as an indicator of academic performance. The final grade of students who attended the near-peer teaching program (69.5 ± 16.0%) was 38.7% higher (P = 0.002, d = 1.06) than those who did not (50.1 ± 20.4%). When the academic performance of the same students was evaluated in another course (exercise physiology) that did not offer a near-peer teaching program, there were no significant differences between the groups (students who attended or did not attend the near-peer teaching program). A significant positive association was found between near-peer teaching program frequency and the number of students approved and not approved in the course (P = 0.041). A significant difference (P = 0.001) was found in the attendance at regular classes between the group who participated in the near-peer teaching program (median: 62 hours; IQR [interquartile ranges]: 4.0 hours) and those who did not (median: 58 hours; IQR: 4.0 hours). Gender was not a moderating factor on academic performance or near-peer teaching program attendance. These results highlight the effectiveness of a near-peer teaching program on the academic performance of students from a sport and exercise science degree program while enrolled in an anatomy course. Anat Sci Educ. © 2018 American Association of Anatomists.  相似文献   
5.
This article is concerned with the control of a Semi-Active suspension system of a 7DOF Full Vehicle model, equipped with four Electro Rheological (ER) dampers, taking into account their incipient dissipativity constraints. Herein, a real-time, fast, advanced control structure is presented within the Model Predictive Control framework for Linear Parameter Varying (LPV) systems. The control algorithm is developed to provide a suitable trade-off between comfort and handling performances of the vehicle in a very limited sampling period (Ts=5ms), in view of a possible realtime implementation on a real vehicle. The control structure is tested and compared to other standard fast control approaches. Full nonlinear realistic simulation results illustrate the overall good operation and behaviour of the proposed control approach.  相似文献   
6.
Digital libraries of scientific articles contain collections of digital objects that are usually described by bibliographic metadata records. These records can be acquired from different sources and be represented using several metadata standards. These metadata standards may be heterogeneous in both, content and structure. All of this implies that many records may be duplicated in the repository, thus affecting the quality of services, such as searching and browsing. In this article we present an approach that identifies duplicated bibliographic metadata records in an efficient and effective way. We propose similarity functions especially designed for the digital library domain and experimentally evaluate them. Our results show that the proposed functions improve the quality of metadata deduplication up to 188% compared to four different baselines. We also show that our approach achieves statistical equivalent results when compared to a state-of-the-art method for replica identification based on genetic programming, without the burden and cost of any training process.  相似文献   
7.
This paper is aimed to investigate the operating characteristics of a static synchronous compensator (STATCOM) integrated with superconducting magnetic energy storage (SMES) for high power applications in the transmission network level. The STATCOM controller topology comprises multi-level multi-pulse neutral-point clamped-type (NPC) voltage source inverters (VSIs) using the harmonics cancellation technique, and incorporates a SMES coil. An innovative two-quadrant multi-level dc-dc converter is proposed to effectively interface the STATCOM with the superconducting coil using a buck-boost topology with neutral point voltage control capabilities; thus enabling to simultaneously control both active and reactive power exchange with the high voltage power system. A detailed analysis of major system variables is presented, including analytical results and digital simulations using the MATLAB/Simulink environment. Moreover, a three-level control scheme is designed, including a full decoupled current control strategy in the d-q reference frame with a novel controller to prevent the STATCOM dc bus capacitors voltage drift/imbalance and an enhanced power system frequency controller.  相似文献   
8.
The painting Proas Iluminadas (Illuminated Bows) by Benito Quinquela Martín is studied by Raman spectroscopy in order to analyse the technique and the pigments employed by the artist: ultramarine blue, carbon black, cadmium-sulphure based compounds for the hue of yellow, orange and red; also zinc white, barium yellow, massicot yellow and viridian were observed. The importance of using different excitation laser lines in the analysis of mixtures of pigments is highlighted. The Raman mapping analysis of cross section samples shows the way the artist composed the ground layer: a lead white stratum over a calcite one. It also allows distinguishing between a mixture of components and strata superposition, both presenting the same appearance under an optical microscope. This paper provides information about the materials and techniques used in a period of Argentine art not studied before from this point of view.  相似文献   
9.
ABSTRACT

We present the determinants of the length of stay (LOS) of Porto Street Stage that integrated the program of the 52nd edition of Rally de Portugal. Sport events assume an important role in the marketing of tourism destinations. However, when we compare them with other segments in tourism, it still remains underexplored. This study represents an opportunity to contribute to the literature, and it could become a significant toll for the organizers, public entities and other stakeholders. We contemplate a set of information and data that may improve the management of the future editions in a more rigorous and effective way. As we are dealing with an international event, it is an occasion to enlist tourists and promote the tourist destination. We applied a quantitative analysis and considered the sociodemographic characteristics of the spectators, factors that influenced the trip, expenses per day in the city, level of satisfaction with the event, and the intention to return. An OLS regression model, a Weibull survival model and a zero-truncated negative binomial regression model were estimated, and the results were compared. On the LOS determinants it is not common to consider the influence of each item of expenditure during the stay and the satisfaction levels with the event and different effects were observed. The travel and accommodation expenditures present a negative effect on the LOS. In the opposite side the satisfaction level and intention to return, both present a positive effect on the LOS. The sociodemographic characteristics have diverse impacts on the LOS.  相似文献   
10.
The present experiment sought to further understanding of the effects of personalised audiovisual stimuli on psychological and psychophysiological responses during exercise in adults with obesity. Twenty-four participants (Mage = 28.3, SD = 5.5 years; MBMI = 32.2, SD = 2.4) engaged in self-paced exercises on a recumbent cycle ergometer and three conditions (sensory stimulation [ST], sensory deprivation [DE], and control [CO]) were administered. Perceptual (attentional focus and perceived exertion), affective (affective state and perceived activation), and psychophysiological (heart rate variability) parameters were monitored throughout the exercise bouts. A one-way repeated measures analysis of variance was used to compare self-reported and psychophysiological variables (main and interaction effects [5 Timepoints × 3 Conditions]). The results indicate that ST increased the use of dissociative thoughts throughout the exercise session (ηp2 = .19), ameliorated fatigue-related symptoms (ηp2 = .15) and elicited more positive affective responses (ηp2 = .12) than CO and DE. Accordingly, personally-compiled videos are highly effective in ameliorating exertional responses and enhancing affective valence during self-paced exercise in adults with obesity. Audiovisual stimuli could be used during the most critical periods of the exercise regimen (e.g., first training sessions) when individuals with obesity are more likely to focus on fatigue-related sensations.  相似文献   
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