A Performance Evaluation of Surface Normals-Based Descriptors for Recognition of Objects using CAD-Models

This paper describes a study and analysis of surface normal-base descriptors for 3D object recognition. Specifically, we evaluate the behaviour of descriptors in the recognition process using virtual models of objects created from CAD software. Later, we test them in real scenes using synthetic objects created with a 3D printer from the virtual models. In both cases, the same virtual models are used on the matching process to find similarity. The difference between both experiments is in the type of views used in the tests. Our analysis evaluates three subjects: the effectiveness of 3D descriptors depending on the viewpoint of camera, the geometry complexity of the model and the runtime used to do the recognition process and the success rate to recognize a view of object among the models saved in the database.

Construction of Structures I in Moodle: a new teaching methodology in the Degree of Building Engineer

The subject of Construction of Structures I studies, from a constructive point of view and taking into account current legislation, reinforced concrete structures used in buildings, through the acquisition of knowledge and construction criteria required in the profession of a Technical Architect. The contents acquired in this course are essential for further professional development of technicians and are closely related to many of the subjects taught in the same or other courses of the Degree in Technical Architecture at the University of Alicante. The aim of this paper is to present, analyze and discuss the development of a new methodology proposed in the mentioned subject, as it supposed an important change in the traditional way of teaching Construction and Structures I. In order to incorporate new teaching tools in 2013-2014, the course has been implemented by using a Moodle software tool to promote blended learning with online exercises. Our Moodle community allows collaborative work within an open-source platform where teachers and students share a new and personalized learning environment. Students are easily used to the interface and the platform, value the constant connection with teachers or other fellows and completely agree with the possibility of making questions or share documents 24 hours a day. The proposed methodology consists of lectures and practical classes. In the lectures, the basics of each topic are discussed; class attendance, daily study and conducting scheduled exercises are indispensable. Practical classes allow to consolidate the knowledge gained in theory classes by solving professional exercises and actual construction problems related to structures, that shall be compulsorily delivered online. So, after the correction of the teacher and the subsequent feedback of students, practical exercises ensure lifelong learning of the student, who can download any kind of material at any time (constructive details, practical exercises and even corrected exams). Regarding the general evaluation system, goals achievement is assessed on an ongoing basis (65% of the final mark) along the course through written and graphic evidences in person and online, as well as a individual development of a workbook. In all cases, the acquisition of skills, the ability to synthesize, the capacity of logical and critical thinking are assessed. The other 35 % of the mark is evaluated by a complementary graphic exam. Participation in the computing platform is essential and the student is required to do and present, at least 90% of the practices proposed. Those who do not comply with the practices in each specific date could not be assessed continuously and may only choose the final exam. In conclusion, the subject of Construction of Structures I is essential in the development of the regulated profession of Technical Architect as they are considered, among other professional profiles, as specialists in construction of building structures. The use of a new communication platform and online teaching allows the acquisition of knowledge and constructive approaches in a continuous way, with a more direct and personal monitoring by the teacher that has been highly appreciated by almost 100% of the students. Ultimately, it is important to say that the use of Moodle in this subject is a very interesting tool, which was really well welcome by students in one of the densest and important subjects of the Degree of Technical Architecture.

Time-motion analysis in women’s team handball: importance of aerobic performance

Women’s handball is a sport, which has seen an accelerated development over the last decade. Data on movement patterns in combination with physiological demands are nearly nonexistent in the literature. The aim of this study was twofold: first, to analyze the horizontal movement pattern, including the sprint acceleration profiles, of individual female elite handball players and the corresponding heart rates (HRs) during a match and secondly to determine underlying correlations with individual aerobic performance. Players from one German First League team (n = 11) and the Norwegian National Team (n = 14) were studied during one match using the Sagit system for movement analysis and Polar HR monitoring for analysis of physiological demands. Mean HR during the match was 86 % of maximum HR (HRmax). With the exception of the goalkeepers (GKs, 78 % of HRmax), no position-specific differences could be detected. Total distance covered during the match was 4614 m (2066 m in GKs and 5251 m in field players (FPs)). Total distance consisted of 9.2 % sprinting, 26.7 % fast running, 28.8 % slow running, and 35.5 % walking. Mean velocity varied between 1.9 km/h (0.52 m/s) (GKs) and 4.2 km/h (1.17 m/s) (FPs, no position effect). Field players with a higher level of maximum oxygen uptake (V̇O2max) executed run activities with a higher velocity but comparable percentage of HRmax as compared to players with lower aerobic performance, independent of FP position. Acceleration profile depended on aerobic performance and the field player’s position. In conclusion, a high V̇O2max appears to be important in top-level international women’s handball. Sprint and endurance training should be conducted according to the specific demands of the player’s position.

Electrochemical analysis of the performance of carbon supported Pd nanoparticles for direct formic acid fuel cells: from gold supported electrodes to catalyst-coated membranes

In this work carbon supported Pd nanoparticles were prepared and used as electrocatalysts for formic acid electrooxidation fuel cells. The influence of some relevant parameters such as the nominal Pt loading, the Nafion/total solids ratio as well as the Pd loading towards formic acid electrooxidation was evaluated using gold supported catalytic layer electrodes which were prepared using a similar methodology to that employed in the preparation of conventional catalyst coated membranes (CCM). The results obtained show that, for constant Pd loading, the nominal Pd loading and the Nafion percentage on the catalytic layer do not play an important role on the resulting electrocatalytic properties. The main parameter affecting the electrocatalytic activity of the electrodes seems to be the Pd loading, although the resulting activity is not directly proportional to the increased Pd loading. Thus, whereas the Pd loading is multiplied by a factor of 10, the activity is only twice which evidences an important decrease in the Pd utilization. In fact, the results obtained suggest the active layer is the outer one being clearly independent of the catalytic layer thickness. Finally, catalyst coated membranes with Pd catalyst loadings of 0.1, 0.5 and 1.2 mg cm-2 were also tested in a breathing direct formic acid fuel cell.