Effect of different loading conditions on running mechanics at different velocities     

Germán Carretero-Navarro  Doménico Cherubini  Wolfgang Taube 《European Journal of Sport Science》2019,19(5):595-602

Weighted vests are widely used to improve running economy and performance. However, it is not well-studied how running mechanics are adapted to counteract the higher peak vertical ground reaction forces (Fpeak) while running with such a device. Therefore, the present study aimed to investigate the effects of different loading conditions on running mechanics at different velocities. Thirteen subjects participated in two separate sessions one week apart. In the first session, maximal aerobic speed (MAS) was determined through a maximal incremental running test while in the second session, they were instructed to run during one minute under different loading (0%, +10% and +20% of body mass [BM]) and velocity (60%, 80% and 100% of MAS) conditions in a random order. Spatiotemporal data were recorded and then running mechanics modelled using the spring-mass model. The main results indicated that vertical and leg stiffness (Kvert and Kleg, respectively) were increased (P?P?>?.05) when load was changed. At the same time, alterations of the running kinematics were observed such as longer contact times, reduced flight times, stride frequencies and step lengths, as well as an increase of the centre of mass dynamics. Based on these results it is assumed that runners maintain a certain stiffness level for each velocity despite different loading conditions. As a consequence, Fpeak increases and this probably causes spatiotemporal adjustments in the movement kinematics.  相似文献   

Quality flaw prediction in Spanish Wikipedia: A case of study with verifiability flaws     

Edgardo Ferretti  Leticia Cagnina  Viviana Paiz  Sebastián Delle Donne  Rodrigo Zacagnini  Marcelo Errecalde 《Information processing & management》2018,54(6):1169-1181

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prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove).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   

Supercomplexity and the university: Ronald Barnett and the social philosophy of Higher Education          下载免费PDF全文

Søren S. E. Bengtsen 《Higher Education Quarterly》2018,72(1):65-74

Ronald Barnett's modern classic Realizing the University in an Age of Supercomplexity (published December 1999), has had a crucial impact internationally on the field of Higher Education research and development since the book was published now nearly 20 years ago. Bridging an academic oeuvre across almost 30 years with close to 30 published volumes, Realizing the University in an Age of Supercomplexity plays an important role in the development and transformation of Barnett's social theory of Higher Education into a social philosophy of Higher Education. In the book Barnett performs an important move from a focus on knowledge and epistemology to a focus on being and ontology in relation to Higher Education practices. Barnett shifts his fundamental perspective and view on the relation between universities and the wider society from one of caution and worry to a perspective of hope and vision that fully embraces the future of Higher Education. This way, Realizing the University in an Age of Supercomplexity has not only paved the way for Barnett's own development of a social philosophy of Higher Education, but also contributed invaluably to the rise and maturing of philosophy of Higher Education as a research field in its own right.  相似文献   

Introduction: Scientific and Technological Textbooks in the European Periphery     

José Ramón Bertomeu-sánchez  Antonio García-Belmar  Anders Lundgren  Manolis Patiniotis 《Science & Education》2006,15(7-8):657-665

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The View from Above: Map Reading Skills Project     

Derek Potgieter  Sandra Olën 《International Information and Library Review》1993,25(4)

In South Africa the education system for black children is fraught with problems. These problems are the direct result of apartheid and have been compounded by poverty and illiteracy. In this article the problem of poorly qualified or unqualified teachers is discussed especially with regard to the teaching of map skills to children in their fifth school year. The project team needed to develop affordable materials which could be used in large classes by teachers after a very short period of training. Books and other materials which are available commercially were examined, but for various reasons were found to be unsuitable for local conditions. After determining the extent of the problem, the project team followed a grassroots process of developing a flip chart which teachers learnt to use with confidence and which enabled pupils to master the concepts and skills necessary for understanding a map.  相似文献   

THE INCREDIBLE EXPANDING UNIVERSE     

n.clars 《科学中国》2003,(12):80

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Multilingual modeling of cross-lingual spelling variants     

Krister Lindén 《Information Retrieval》2006,9(3):295-310

Technical term translations are important for cross-lingual information retrieval. In many languages, new technical terms have a common origin rendered with different spelling of the underlying sounds, also known as cross-lingual spelling variants (CLSV). To find the best CLSV in a text database index, we contribute a formulation of the problem in a probabilistic framework, and implement this with an instance of the general edit distance using weighted finite-state transducers. Some training data is required when estimating the costs for the general edit distance. We demonstrate that after some basic training our new multilingual model is robust and requires little or no adaptation for covering additional languages, as the model takes advantage of language independent transliteration patterns. We train the model with medical terms in seven languages and test it with terms from varied domains in six languages. Two test languages are not in the training data. Against a large text database index, we achieve 64–78 % precision at the point of 100% recall. This is a relative improvement of 22% on the simple edit distance.  相似文献   

Retrieving and classifying instances of source code plagiarism     

Debasis?GangulyEmail authorView author&#;s OrcID profile  Gareth?J.?F.?Jones  Aarón?Ramírez-de-la-Cruz  Gabriela?Ramírez-de-la-Rosa  Esaú?Villatoro-Tello 《Information Retrieval》2018,21(1):1-23

Automatic detection of source code plagiarism is an important research field for both the commercial software industry and within the research community. Existing methods of plagiarism detection primarily involve exhaustive pairwise document comparison, which does not scale well for large software collections. To achieve scalability, we approach the problem from an information retrieval (IR) perspective. We retrieve a ranked list of candidate documents in response to a pseudo-query representation constructed from each source code document in the collection. The challenge in source code document retrieval is that the standard bag-of-words (BoW) representation model for such documents is likely to result in many false positives being retrieved, because of the use of identical programming language specific constructs and keywords. To address this problem, we make use of an abstract syntax tree (AST) representation of the source code documents. While the IR approach is efficient, it is essentially unsupervised in nature. To further improve its effectiveness, we apply a supervised classifier (pre-trained with features extracted from sample plagiarized source code pairs) on the top ranked retrieved documents. We report experiments on the SOCO-2014 dataset comprising 12K Java source files with almost 1M lines of code. Our experiments confirm that the AST based approach produces significantly better retrieval effectiveness than a standard BoW representation, i.e., the AST based approach is able to identify a higher number of plagiarized source code documents at top ranks in response to a query source code document. The supervised classifier, trained on features extracted from sample plagiarized source code pairs, is shown to effectively filter and thus further improve the ranked list of retrieved candidate plagiarized documents.  相似文献   

From Archive,to Access,to Experience––Historical Documents as a Basis for Immersive Experiences     

Jiawei Huang  Mahda M. Bagher  Heather Dohn Ross  Nathan Piekielek  Jan Oliver Wallgrün  Jiayan Zhao 《Journal of Map & Geography Libraries》2018,14(1):40-63

Libraries have been the key to preserving culture and historic legacy for centuries. One such treasure cataloged in The Pennsylvania State University (Penn State) Libraries is a collection of over 33,000 Sanborn? Fire Insurance Maps. Originally kept safe in metal drawers, the library has embarked on a journey to digitize this abundance of information, combine it with other media such as photographs, and make it accessible through a web interface. Inspired by these efforts, we accessed this information and took it to the next level. Using state of the art 3D modeling and immersive technologies, we created a historic 3D model and immersive experiences of Penn State, exemplarily for the 1922 campus. The resulting experiences can be accessed through the web but also through head mounted displays (HMDs) and mobile phones in combination with VR viewers such as the Google Cardboard. Additionally, they can be used anywhere in the world or on the campus itself as a way to enable remote and in situ experiences and learning. Immersive experiences let us connect to the past, the present and the future, and as such offer value to digital cultural heritage efforts.  相似文献   

Investigating the quality of interactions and public engagement around scientific papers on Twitter     

Fereshteh Didegah  Niels Mejlgaard  Mads P. Sørensen 《Journal of Informetrics》2018,12(3):960-971

This study explores science communication on Twitter by investigating a sample of tweets referring to academic papers in five different scientific fields. The specifications of science communicators on Twitter, the characteristics of those who initiate actions (by tweeting), the extent and quality of reactions (retweeting), individual and group interactions, and the distribution of tweets across types of engagement in the process of science communication (i.e., dissemination, consultation, and evaluation) were explored. A broad array of actors is involved in the communication of science on Twitter, with individual citizens and individual researchers playing an important role. In principle, this is promising for creating direct interaction, which can be difficult through more traditional mass media. The vast majority of communication activities regarding academic papers is undigested dissemination with almost no sign of debate, contestation, or collective reflection. Another general finding of this study is that bot accounts play a major role in the science communication landscape on Twitter.  相似文献