2,448 research outputs found
Museum libraries in Spain: A case study at state level
Special libraries are essential information and documentation centres for university teachers and researchers due to the quality and richness of their collections. In Spain, it is estimated that there are 2456 special libraries, although many are unknown either generally or among information professionals. These include museum libraries, which are important centres with valuable collections of bibliographic heritage for the area of Humanities and Social Sciences. The aim of this research is to gain an understanding of the real state of these information units and promote the social value of museum libraries in Spain. To do this, a survey was sent to the libraries of state-owned and -managed museums under the General Directorate of Fine Arts and Cultural Property (Ministry of Culture and Sports) of the Government of Spain. This general objective will be accompanied by a review of the scientific literature on various aspects of museum libraries at national and international level. After addressing the research methodology, the results obtained will be discussed and will include the following topics: collection management, library services and staff, economic and technological resources and finally, library management. Conclusions include recommendations for museum librarians and reveal that institutional cooperation is a strategic issue to improve both museum libraries visibility and their social recognition as cultural and research centre
Geographic mobility and social inequality among Peruvian university students
The purpose of this study was to explore geographic mobility among university students in Peru and to understand how mobility patterns differ by region and by demographic indicators of inequality. The ways that students may be able to move geographically in order to access quality higher education within the educational system can be a driver of equality or inequality, depending on who is able to take advantage. Using data from a university census, we examine how demographic indicators of inequality are related to geographic mobility for university attendance, how prior geographic mobility predicts later mobility for university attendance, and how these relationships differ based on the number and quality of universities in a region. Results show that sociodemographic variables related to social inequality explain a substantial amount of students\u27 postsecondary mobility. However, some of these relationships do not operate in the same way in all of the regions. Depending on the availability of universities and their quality, patterns of association between inequality and geographic mobility change. Implications for higher education policy as well as further research examining geographic mobility and inequality in education are discussed
Multirate control with incomplete information over Profibus-DP network
This is an Accepted Manuscript of an article published by Taylor & Francis in International Journal of Systems Science on 2014, available online:http://www.tandfonline.com/10.1080/00207721.2013.844286When a process ¿eld bus-decentralized peripherals (Pro¿bus-DP) network is used in an industrial environment, a deterministic
behaviour is usually claimed. However, due to some concerns such as bandwidth limitations, lack of synchronisation among
different clocks and existence of time-varying delays, a more complex problem must be faced. This problem implies the
transmission of irregular and, even, random sequences of incomplete information. The main consequence of this issue is
the appearance of different sampling periods at different network devices. In this paper, this aspect is checked by means of
a detailed Pro¿bus-DP timescale study. In addition, in order to deal with the different periods, a delay-dependent dual-rate
proportional-integral-derivative control is introduced. Stability for the proposed control system is analysed in terms of linear
matrix inequalitiesThe authors are grateful to the financial support of the Spanish Ministry of Economy and Competitivity [Research Grant TEC2012-31506].Salt Llobregat, JJ.; Casanova Calvo, V.; Cuenca Lacruz, ÁM.; Pizá Fernández, R. (2014). Multirate control with incomplete information over Profibus-DP network. International Journal of Systems Science. 45(7):1589-1605. https://doi.org/10.1080/00207721.2013.844286S15891605457Alves, M., & Tovar, E. (2007). Real-time communications over wired/wireless PROFIBUS networks supporting inter-cell mobility. Computer Networks, 51(11), 2994-3012. doi:10.1016/j.comnet.2007.01.001Boyd, S., El Ghaoui, L., Feron, E., & Balakrishnan, V. (1994). Linear Matrix Inequalities in System and Control Theory. doi:10.1137/1.9781611970777Bucher, R., & Balemi, S. (2006). Rapid controller prototyping with Matlab/Simulink and Linux. Control Engineering Practice, 14(2), 185-192. doi:10.1016/j.conengprac.2004.09.009Casanova, V., & Salt, J. (2003). 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Integrated Communication and Control Systems: Part I—Analysis. Journal of Dynamic Systems, Measurement, and Control, 110(4), 367-373. doi:10.1115/1.3152698Khargonekar, P., Poolla, K., & Tannenbaum, A. (1985). Robust control of linear time-invariant plants using periodic compensation. IEEE Transactions on Automatic Control, 30(11), 1088-1096. doi:10.1109/tac.1985.1103841Lall, S., & Dullerud, G. (2001). An LMI solution to the robust synthesis problem for multi-rate sampled-data systems. Automatica, 37(12), 1909-1922. doi:10.1016/s0005-1098(01)00167-4Lee, I. W. C., & Dash, P. K. (2003). S-transform-based intelligent system for classification of power quality disturbance signals. IEEE Transactions on Industrial Electronics, 50(4), 800-805. doi:10.1109/tie.2003.814991Lee, C. K., Ron Hui, S. Y., & Henry Shu-Hung Chung. (2002). A 31-level cascade inverter for power applications. 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IEEE Transactions on Circuits and Systems I: Regular Papers, 53(10), 2306-2317. doi:10.1109/tcsi.2006.882824Moayedi, M., Foo, Y. K., & Soh, Y. C. (2011). Filtering for networked control systems with single/multiple measurement packets subject to multiple-step measurement delays and multiple packet dropouts. International Journal of Systems Science, 42(3), 335-348. doi:10.1080/00207720903513335Peñarrocha, I., Sanchis, R., & Romero, J. A. (2012). State estimator for multisensor systems with irregular sampling and time-varying delays. International Journal of Systems Science, 43(8), 1441-1453. doi:10.1080/00207721.2011.625482Piza, R., Salt, J., Sala, A., & Cuenca, A. (2014). Hierarchical Triple-Maglev Dual-Rate Control Over a Profibus-DP Network. IEEE Transactions on Control Systems Technology, 22(1), 1-12. doi:10.1109/tcst.2012.2222883Ray, A. (1989). Introduction to networking for integrated control systems. 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Corn yield response to crowding stress and cropping season
Corn (Zea mays L.) is planted in two seasons per year in northern Iran (mid-April as a main crop and mid-June as a second crop). The main objective of this study was to determine whether corn yield response would differ between these two seasons and different plant populations. Two field experiments were conducted at the Agricultural Research Center of Golestan - Iran in 2007 and 2008 at different planting densities. The results showed that the values of grain yield and most traits were significantly lower in the second season. Maximum grain yield was observed at planting densities of 6.5 plants m -2 in the first season, whereas in the second season grain yield was the same for planting densities between 2.5 and 12.5 plants m -2. Based on the second-year experimental results, the following functions were fitted to show the relationship between yield ha -1 (Y) and planting densities (X) for the first and second seasons, respectively: (Y = -167.6X 2 + 2672.2X + 511.77; R 2 = 0.992) and (Y = 1200.1 ln(X) + 2924.4; R 2 = 0.935). This study found that the optimum plant population was 6.5 plants m -2 under low heat stress, and should be reduced to 2.5-4.5 plants m -2 under heat stress conditions
Clinical haematology of the great bustard (Otis tarda)
The haematological parameters of healthy great bustards (Otis tarda L.) have been determined. The values obtained were red cell count (3.0 x 10(12) +/- 0.2 x 10(12/)1), white cell count (33.0 x 10(9) +/- 2.6 x 10(9)/1), haematocrit value (0.51 +/- 0.01 1/1), haemoglobin (13.0 +/- 0.3 g/dl), mean corpuscular volume (178.7 +/- 12.5 fl), mean cell haemoglobin concentration (25.0 +/- 0.6 g/dl), mean corpuscular haemoglobin (42.5 +/- 3.2 pg), differential white cell count: heterophils (22.5 x 10(9) +/- 0.7 x 10(9)/1), lymphocytes (6.0 x 10(9)+/-0.7 x 10(9)/1), eosinophils (2.7 x 10(9) +/- 0.3 x 10(9)/1) and monocytes (1.8 x 10(9)+/-0.2 x 10(9)/1)
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Potential applications of wrought magnesium alloys for passenger vehicles
Vehicle weight reduction is one of the major means available for improving automotive fuel efficiency. Although high-strength steels, aluminum (Al), and polymers are already being used to achieve significant weight reductions, substantial additional weight reductions could be achieved by increased use of magnesium (Mg) and its alloys, which have very low density. Magnesium alloys are currently used in relatively small quantities for auto parts; use is generally limited to die castings, such as housings. The Center for Transportation Research at Argonne National Laboratory has performed a study for the Lightweight Materials Program within DOE`s Office of Transportation Materials to evaluate the suitability of wrought Mg and its alloys to replace steel or aluminum for automotive structural and sheet applications. This study identifies technical and economic barriers to this replacement and suggests R&D areas to enable economical large-volume use. Detailed results of the study will be published at a later date. Magnesium sheet could be used in body nonstructural and semi-structural applications, while extrusions could be used in such structural applications as spaceframes. Currently, Mg sheet has found limited use in the aerospace industry, where costs are not a major concern. The major barrier to greatly increased automotive use is high cost; two technical R&D areas are identified that could enable major reductions in costs. These are novel reduction technology and better hot-forming technology, possibly operating at lower temperatures and involving superplastic behavior
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Potential automotive uses of wrought magnesium alloys
Vehicle weight reduction is one of the major means available to improve automotive fuel efficiency. High-strength steels, aluminum (Al), and polymers are already being used to reduce weight significantly, but substantial additional reductions could be achieved by greater use of low-density magnesium (Mg) and its alloys. Mg alloys are currently used in relatively small quantities for auto parts, generally limited to die castings (e.g., housings). Argonne National Laboratory`s Center for Transportation Research has performed a study for the Lightweight Materials Program within DOE`s Office of Transportation Materials to evaluate the suitability of wrought Mg and its alloys to replace steel/aluminum for automotive structural and sheet applications. Mg sheet could be used in body nonstructural and semi-structural applications, while extrusions could be used in such structural applications as spaceframes. This study identifies high cost as the major barrier to greatly increased Mg use in autos. Two technical R and D areas, novel reduction technology and better hot-forming technology, could enable major cost reductions
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Analysis of the potential for new automotive uses of magnesium
This paper describes the scope of a new project, just initiated, for the Lightweight Materials Program within the Office of Transportation Materials. The Center for Transportation Research and the Energy Technology Division at Argonne National Laboratory will assess the feasibility and technical potential of using magnesium and its alloys in place of steel or aluminum for automotive structural and sheet applications in order to enable more energy-efficient, lightweight passenger vehicles. The analysis will provide an information base to help guide magnesium research and development in the most promising directions
Pleistocene cave hyenas in the Iberian Peninsula: New insights from los aprendices cave (Moncayo, Zaragoza)
A new Pleistocene paleontological site, Los Aprendices, located in the northwest-ern part of the Iberian Peninsula in the area of the Moncayo (Zaragoza) is presented. The layer with fossil remains has been dated by amino acid racemization to 143.8 ± 38.9 ka (earliest Late Pleistocene or latest Middle Pleistocene). Five mammal species have been identified in the assemblage: Crocuta spelaea (Goldfuss, 1823) Capra pyre-naica (Schinz, 1838), Lagomorpha indet, Arvicolidae indet and Galemys pyrenaicus (Geoffroy, 1811). The remains of C. spelaea represent a mostly complete skeleton in anatomical semi-connection. The hyena specimen represents the most complete skel-eton ever recovered in Iberia and one of the most complete remains in Europe. It has been compared anatomically and biometrically with both European cave hyenas and extant spotted hyenas. In addition, a taphonomic study has been carried out in order to understand the origin and preservation of these exceptional remains. The results sug-gest rapid burial with few scavenging modifications putatively produced by a medium sized carnivore. A review of the Pleistocene Iberian record of Crocuta spp. has been carried out, enabling us to establish one of the earliest records of C. spelaea in the recently discovered Los Aprendices cave, and also showing that the most extensive geographical distribution of this species occurred during the Late Pleistocene (MIS4-2)
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