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911.
Julio M. del Hoyo-Melndez Marion F. Mecklenburg María Teresa Domnech-Carb 《Journal of Cultural Heritage》2011,12(1):54
This paper presents the results of a light levels survey conducted at the Donald W. Reynolds Center for American Art and Portraiture in Washington DC. The museum space is shared by the National Portrait Gallery and the Smithsonian American Art Museum. After six years of extensive renovations, the building reopened to the public in July 1, 2006. The structure was not originally designed to house a museum collection since it contains numerous openings such as windows, doors and skylights, which provide a path for natural radiation to enter the building and come in contact with the artworks. From a preventive conservation standpoint, this is an important problem since sensitive works of art in the collection may be subjected to damage caused by light exposure. Environmental data loggers installed throughout the museum were programmed to take successive measurements every 10 min for 24 h a day, 7 days a week and 52 weeks a year. This light levels assessment started in November 1, 2007 and finished in October 31, 2008. This study presents a new method for determining natural radiation exposures registered in exhibition spaces that rely on both electric lighting and natural lighting, considering the growing trend of using daylight illumination in museums. 相似文献
912.
The renaissance frescoes of the metropolitan cathedral of Valencia, located at the vault of the apse, were restored in 2006. We describe a microclimate monitoring system that was implemented for the preventive conservation of the paintings. It is comprised by a set of temperature and relative humidity sensors positioned at different points of the vault. This system is rather unique because some of these sensors were inserted inside the paintings during the restoration process. A principal components analysis was applied to the data of relative humidity recorded in February 2007. The analysis was repeated in three additional months of 2007. The resulting loading plots highlight the most relevant similarities and dissimilarities among sensors. These plots can be considered as some sort of control maps that could be used to detect abnormal conditions in the future. Actually, moisture problems at certain zones of the frescoes are causing the formation of efflorescence, and the sensors located close to these zones are the ones recording the highest values of relative humidity. 相似文献
913.
Pedro Martín Lerones José Llamas Fernández Álvaro Melero Gil Jaime Gómez-García-Bermejo Eduardo Zalama Casanova 《Journal of Cultural Heritage》2010,11(1):1-9
On many occasions, the graphic information handled by people working in the cultural heritage sector is still bidimensional. Layouts showing elevations and cross sections are the most widespread tools. However, there is an increased need for carefully detailing the complexity of valuable sites with an improved accuracy. This implies the measuring and handling of three-dimensional data, using both commercial and turn-key hardware and software solutions. Taking the usual traditional process as a reference, in the present paper a new effective methodology for carrying out computer assisted delineation of layouts from cultural heritage sites, using 3D digital models, is described. The proposed procedure has been tested in five intervention projects on representative churches within the “Merindad de Aguilar de Campoo” medieval area, in the north of Spain.1 This area has the largest collection of Romanesque art in the world, and is currently under European Heritage Site and World Heritage Site declaration process by the UNESCO. 相似文献
914.
Determinants of possession of the ball in soccer 总被引:1,自引:0,他引:1
In research on the importance of the possession of the ball in soccer, little attention has been paid to its determinants. Using data from 170 matches of the 2003 - 2004 Spanish Soccer League, we explain why differences in the possession of the ball among teams are so great. In particular, four variables are examined: evolving match status (i.e. whether the team is winning, losing or drawing), venue (i.e. playing at home or away), and the identities of the team and the opponent in each match. Results of linear regression analysis show that these four variables are statistically significant and together explain most of the variance in possession. In short, home teams have more possession than away teams, teams have more possession when they are losing matches than when winning or drawing, and the identity of the opponent matters - the worse the opponent, the greater the possession of the ball. Combinations of these variables could be used to develop a model that predicts possession in soccer. 相似文献
915.
Aleksandra S. Panajotovi? Mihajlo ?. Stefanovi? Dragan Lj. Dra?a 《Journal of The Franklin Institute》2010,347(7):1242-1252
We study the performance of dual branch switch and stay combining (SSC) diversity receivers operating over correlated Rician fading channels, in the presence of correlated Rayleigh distributed cochannel interference (CCI). Fast convergent infinite series representations for both the joint probability density function (PDF) of the SSC input signal-to-interference ratios (SIRs) and the PDF of the SSC output SIR are derived. The last one is applied to semi-analytically study the average bit error probability (ABEP) of differential binary phase shift keying (DBPSK). Furthermore, the optimum switching threshold in the sense of minimum ABEP is obtained numerically and the effects of fading severity and branch correlation on both ABEP and optimum switching threshold are investigated. Numerical and simulation results are presented to support the mathematical analysis. 相似文献
916.
José Domingo?García-MerinoEmail author Gerardo?Arregui-Ayastuy Arturo?Rodríguez-Castellanos Lidia?García-Zambrano 《知识管理研究与实践》2010,8(4):340-350
This paper aims to analyze the companies’ view about the financial valuation of intangibles relevance and its influence on corporate performance. Based on the theory of resources, the role of intangibles in business competitiveness is justified. The traditional factors of production have become secondary, while the success is primarily based on the development and utilization of intangible resources. One of the main problems in managing the intangibles appears to be that, there is a general lack of information about them. Therefore, financial valuation of intangibles will result in significant benefits to the organization that will help determine business strategy, process design as well providing competitive advantage. It follows the hypothesis of this work, the greater known about their intangibles and the greater sensitivity to the financial valuation of them, the better performance. To achieve this objective, a field study is done, doing telephone calls to Basque Country companies’ financial managers. 相似文献
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AbstractIn this article, we study how mountain guiding was organized and regulated in Scandinavia and the Alps between 1820 and 2015 and focus on the most important differences and similarities in Scandinavia, and between Scandinavia and the Alps. We conclude that Switzerland and Chamonix (France) represent two different systems in the Alps during the nineteenth century. However, through the emergence of national and international guide unions the regulation of mountain guiding in the Alps today appears unified, with a close connection between national regulation and mountain guide unions. In Scandinavia, Norway and Sweden historically had similar practices organizing and regulating mountain guiding, where a relatively strong layman tradition emerged during the 1960s and 1970s. In 2008, legal decisions led Sweden to change its system to match the Alp model, while Norway held on to the layman tradition. This leaves mountain guiding in Norway as a distinctly less regulated field than in France, and Switzerland, as in and Sweden. 相似文献