935 research outputs found
Adaptive OFDM and CDMA Algorithms for SISO and MIMO Channels
No full textThe objective of this thesis is to study adaptive modulation algorithms for Single Input Single Output (SISO) and Multiple Input Multiple Output (MIMO) channels. The adaptive modulation technique has the advantages of flexibility, providing high transmission quality and throughput; and it can lead to a smaller volume of radio and more applications. The major contribution of the author is discussed in the following paragraphs. To the best of the authorâs knowledge, the strategy and working procedures of the adaptive modulation technique have not yet been described in the literature. We propose strategies and work procedures for adaptive modulation in this dissertation. In addition, for the first time, it is proposed that the development of adaptive modulation consists of three stages, in which the adaptivity is taken to a higher level. We assert in this thesis that adaptive modulation algorithms involve two themes, i.e., channel and modulation. We analyze two types of channels: SISO and MIMO channels. We investigate the SISO channel in time, frequency, and space domains, which is efficient for designing adaptive modulation algorithms. Further, initially we propose three approaches as solutions to problems in each of the domains, i.e., adaptive techniques (time domain), OFDM (frequency domain), and MIMO technique (space domain). These three approaches are investigated in this thesis. We study the concept, structure, and characteristics of MIMO channels. The gains of three MIMO schemes and parameters influencing these gains are generalized. What is more, we introduce a new factor, the Rician K gain, to describe the MIMO gain with respect to that of SISO channels. In addition, we work out the SNR gains of these three MIMO schemes compared with SISO channels for a large SNR range, which have not been found in literature. This is indispensable for the design of adaptive modulation algorithms for MIMO channels. With regard to modulation, we list the parameters of OFDM and CDMA modulations for adaptive OFDM and adaptive CDMA algorithms to be designed. In order to obtain direct relationships between modulation parameters and throughput, we derive two throughput formulas, an OFDM formula and a CDMA formula. We show that the traditional commonly held belief that the subcarrier bandwidth influences transmission quality is true only if the channel RDS is constant. To explain this, we define a new parameter, PFR, as the product of subcarrier bandwidth and RDS. How this parameter works and by what factors it is limited are studied in this thesis. Subsequently, we propose three successful adaptive modulation algorithms, i.e., an adaptive OFDM algorithm for SISO channels, an adaptive OFDM algorithm for MIMO channels, and an adaptive CDMA algorithm for MIMO channels. Perfect channel estimation is assumed in our work. For the adaptive OFDM algorithms, we propose three subband settings. Remarkable throughput gains are obtained from all these adaptive modulation algorithms in simulations. We put forward the new idea of employing more than one MIMO scheme in a system and adapting these schemes using our adaptive modulation algorithms. Simulation results show that extra gains can be obtained by this method. The performance gains of our algorithms are dependent on the channel situation. The influence of channel parameters on these relative gains is investigated in this work as well. We introduce an SNR boundary matrix to set processing gains and modulation levels in our adaptive CDMA algorithm for MIMO channels.Electrical Engineering, Mathematics and Computer Scienc
Impressions of anglo-indian society in R. Kipling's early creative art
No full textThis study concentrates on the analysis of early works by Rudyard Kipling who was born into the family of English colonists to India, thus becoming a representative of the newly formed Anglo-Indian society. The writer's sketch Anglo-Indian Society (1887) and his collection of short stories Plain Tales from the Hills (1888) depict the characteristic features of Anglo-Indians’ worldview and lifestyle, which are revealed and analyzed by the author of the article. Special attention is paid to biographical factors influencing the author’s choice of Anglo-Indian topic at the beginning of his writing career. The researcher concludes that Kipling presents in his works an outline of Anglo-Indian society which emerged from the writer's observations of Anglo-Indians' lives during his work as a reporter. Striving for credibility in consideration of advantages and shortcomings of Anglo-Indian worldview and lifestyle, the author tries to occupy the position of the unconcerned observer, being capable of assessing the situation with fresh mind. Kipling disguises himself under the image of the hero-narrator, being either a tourist traveler from abroad, or a reporter, accustomed to collecting factual material for the local paper, in such a way receiving an opportunity to speak ironically and sometimes even sarcastically about certain models of behavior, accepted by Anglo-Indians
Copyright, contratto e accesso alla conoscenza: un’analisi comparata = Copyright, contract and access to knowledge: a comparative analysis.
No full textIl processo di digitalizzazione e lo sviluppo dei media, stravolgendo il paradigma tradizionale del copyright/diritto d’autore conducono a reazioni opposte. Da un lato, estendendo in vario modo l’ampiezza dell’esclusiva autorale favoriscono l’adozione di regole restrittive di accesso e uso dei contenuti; dall’altro, alimentano le logiche di condivisione, specie in alcune aree di produzione del sapere.
Il contratto, pur mutata la propria natura nella dimensione digitale, rappresenta la prima leva per l’affermazione di tali divergenti dinamiche, che, in entrambe le direzioni, riguardano anche la circolazione della conoscenza scientifica. Nel senso dell’apertura, lo strumento negoziale consente di perseguire i principi affermati dal movimento dell’Open Access (OA), abbattendo le barriere economiche e giuridiche all’accesso e utilizzo dei contenuti.
Dal deposito e pubblicazione su archivi istituzionali e disciplinari di opere transitate già attraverso i canali editoriali convenzionali, comunemente definita green road, alla pubblicazione su riviste ad accesso aperto, gold road, il fenomeno si sviluppa dal basso verso l’alto grazie alle dichiarazioni di principio e alle norme informali che hanno sin ora guidato le comunità accademiche nell’affermazione dell’OA. Di recente, tuttavia, i principi dell’OA sono oggetto di attenzione da parte del decisore pubblico che, pur timidamente, ne “impone” l’attuazione a tutte le comunità accademiche. Eppure, il diritto formale non sembra da solo sufficiente: è soltanto il primo tassello di una disciplina organica tesa a definire regole e incentivi per la produzione e la disseminazione della conoscenza scientifica, allo scopo di bilanciare la libertà “accademica” con il diritto di accesso alla conoscenza. = ENGLISH VERSION = Along with a comparative perspective that takes account of the U.S. and Italian law, this work aims to explore the interface between copyright and contract lae in publishing process.
In the current publishing environment, contracts and technology play a dominant role in the exploitation of copyrighted works. Publishers are granted by assignment of all copyright rights to reproduce and publish the work, but also to exercise control over its contents through technological protection measures. At the same time, mass digitization allows libraries and other organizations to make contents available online, which it entails a redefinition of the traditional publishing process and introduces new players to the scene (e.g., Google Books).
Hence, technology proves to be a powerful instrument for the spread of knowledge and it is on this pattern that Open Access (OA) is rapidly gaining ground.
Mostly based on a bottom-up approach that is on soft law, institutional policies and contracts, OA designs a new legal environment targeting the objectives of free accessibility, further distribution, and proper archiving of publications. These aims can be achieved through the creation of new open access business models to publish on OA journals (gold road) or to self-archive in institutional or disciplinary repositories works that have been originally published in conventional journals (green road).
However, in order for OA to be fully developed it is necessary to devise a principled and feasible approach to the dissemination of scholarly works against the current social, economic and legal background.
Indeed, the importance of OA is steadily recognized by legislators who integrate OA provisions into their legal system. This is an innovation of great significance, which was first fostered in the USA, and then extended in some European countries such as Italy and Germany in the European framework. Nevertheless, considering the different law systems, the formal law need to be combined with national strategies and institutional policies providing adequate incentives to the authors, while also promoting academic freedom and the right to knowledge access
[[alternative]]A Taxonomic Study of Rosa L. (Rosaceae) in Taiwan
No full text[[abstract]]The genus Rosa Linneaus (Rosaceae) in Taiwan is taxonomically revised based on morphological, palynological and phytogeographical studies. Morphology of leaves and stipules are most important characters for the classification of Taiwan taxa. Flower color, styles and hips are useful characters in distinguishing some taxa. Pollen exine sculpture also shows little interspecific difference. Altitudinal, different distribution over different altitudes can also provide useful information.
As a result, nine taxa in Taiwan were recoginzed, including one new species R. pubinervis. Rosa morrisonensis is elevated to species level. Rosa bracteata var. scabriacaulis and R. bracteata var. taiwanensis are treated as synonym of R. bracteata. Rosa henryi is treated as synonym of R. sambucina, and Rosa multiflora var. formosana as synonym of R. transmorrisonensis. Both R. taiwanensis and R. sambucina var. mushaniana are treated as synonyms of R. pricei var. pricei. The existence of R. luciae var. rosea in Taiwan is reconfirmed and transferred as R. pricei var. rosea. Rosa luciae is excluded in the study.
Conference Institutional archives for research: experiences and projects in Open Access Istituto Superiore di Sanità Rome, 30 November - 1 December 2006
No full textThe Congress was organised into four sessions: 1) Open Access (OA) and authors: support from the international community; 2) OA in Italy: knowledge and tools to write and search; 3) institutional policies for OA; 4) opportunities and services to develop OA. It was aimed at achieving the following objectives: a) make authors of biomedical publications aware of the benefits of depositing research material in digital open archives and publishing in OA peer-reviewed journals; b) outline the impact of the OA publishing model on the assessment of research output; c) enhance the adoption of policies encouraging the OA paradigm; d) promote cooperation between research institutions in Italy and abroad to share resources and experiences on institutional repositories. A useful introductory bibliography on the OA publishing model in the biomedical field is included in the Appendix
Analysis of spatial effects in vine and olive crops across Portuguese regions
No full textThe consideration of spatial effects at a regional level is becoming increasingly frequent and the work of Anselin (1988), among others, has contributed to this. This study analyses, through cross-section estimation methods, the influence of spatial effects in the NUTs III vine and olive crops of mainland Portugal, in 1999 (the last data available), considering the Verdoorn relationship as a base of study. To analyse the data, by using Moran I statistics, and estimation results, considering the spatial lag and spatial error component, it is stated that there are positive spatial autocorrelation (variables of each of the regions develop in a similar manner to each of the neighbouring regions), above all in vine.spatial econometrics; vine and olive crops; Portuguese regions
Analysis of spatial effects in vine crop across Portuguese regions
No full textThe consideration of spatial effects at a regional level is becoming increasingly frequent and the work of Anselin (1988), among others, has contributed to this. This study analyses, through cross-section estimation methods, the influence of spatial effects in the NUTs III vine crop of mainland Portugal, in 1999 (the last data available), considering the Verdoorn relationship as a base of study. To analyse the data, by using Moran I statistics, and estimation results, considering the spatial lag and spatial error component, it is stated that there are positive spatial autocorrelation (variables of each of the regions develop in a similar manner to each of the neighbouring regions), in the vine crop.spatial econometrics; vine crop; Portuguese regions
How should be the levels of public and private R&D investments to trigger modern productivity growth? Empirical evidence and lessons learned for Italian economy
No full textGovernments in modern economies devote much policy attention to enhancing productivity and continue to emphasize its drivers such as investment in R&D. This paper analyzes the relationship between productivity growth and levels of public and private R&D expenditures. The economic analysis shows that the magnitude of R&D expenditure by business enterprise equal to 1.58% (% of GDP) and R&D expenditure of government and higher education of 1.06 (% of GDP) maximize the long-run impact on productivity growth. These optimal rates are the key to sustain productivity and technology improvements that are more and more necessary to modern economic growth.R&D investment, Productivity growth, Optimization
Why Should Regional Agricultural Productivity Growth Converge? Evidence from Italian Regions
No full textThe paper analyses agricultural TFP growth across Italian regions during the 1952-2002 period, and aims at identifying those factors that favour or hinder regional agricultural TFP growth convergence. Of major relevance is whether regions, despite their inescapable heterogeneity, tend to share common technological improvements, that is, to move along the same productivity growth rate. TFP growth decomposition ultimately allows attributing observed productivity performance to convergence and divergence forces. Appropriate testing and estimation procedures are adopted to take into account panel unit-root issues and cross-sectional dependence.TFP growth, Convergence, Panel Data, Productivity Analysis,
"...son Lisidora/ che s'ange e s'addolora": la madre di Don Giovanni e altre ombre,
No full textAnalisi del "Nuovo risarcito Convitato di pietra" di G.B. Andreini con particolare attenzione all'invenzione di una madre di Don Giovanni che compare come ombra, fantasma, di qui diverse considerazioni sulle funzioni delle apparizioni nel teatro del Cinque e SeicentoAnalyzing the role of Don Giovanni's mother in the "Nuovo risarcito Convitato di pietra" by the commedia dell'arte author G.B. Andreini, the purpose is to define the use of specters in XVIth and XVIIth century theate
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