15,515 research outputs found
Heart of Darkness: Modeling Public-Private Funding Interactions Inside the R&D Black Box
This paper is a first step toward closing the analytical gap in the extensive literature on the results of interactions between public and private R&D expenditures, and their joint effects on the economy. Earlier studies frequently report contradictory estimates of the response of company financed R&D to changes in the level and nature of public R&D expenditure. A major cause of "inconsistencies" in the empirical literature is the failure to recognize key differences among the various policy "experiments" being considered depending upon the economy in which they are embedded, and the type of public sector R&D spending that is contemplated. Using a simple, stylized structural model, we identify the main channels of impact of public R&D and characterize the various effects, distinguishing between short-run and long-run impacts that would show up in simple regression analyses of nominal public and private R&D expenditure variables. We offer interpretations that shed light on recent cross-section and panel data findings at both high (i.e. national) and low (specific technology area) levels of aggregation.
Heart of Darkness: Modeling Public-Private Funding Interactions Inside the R&D Black Box
This paper is a first step toward closing the analytical gap in the extensive literature on the results of interactions between public and private R&D expenditures, and their joint effects on the economy. Econometric studies in this area report a plethora of sometimes confusing and frequently contradictory estimates of the response of company financed R&D to changes in the level and nature of public R&D expenditure, but the necessary theoretical framework within which the empirical results can be interpreted is seldom provided. A major cause of inconsistencies' in the empirical literature is the failure to recognize key differences among the various policy experiments' being considered depending upon the economy in which they are embedded, and the type of public sector R&D spending that is contemplated. Using a simple, stylized structural model, we identify the main channels of impact of public R&D. We thus can characterize the various effects, distinguishing between short-run and long-run impacts that would show up in simple regression analyses of nominal public and private R&D expenditure variables. Within the context of our simple model it is possible to offer interpretations that shed light on recent cross-section and panel data findings at both high (i.e. national) and low (specific technology area) levels of aggregation.
The effect of swirl recovery vanes on the cruise noise of an advanced propeller
The SR-7A propeller was acoustically tested with and without downstream swirl recovery vanes to determine if any extra noise was caused by the interaction of the propeller wakes and vortices with these vanes. No additional noise was observed at the cruise condition over the angular range tested. The presence of the swirl recovery vanes did unload the propeller and some small peak noise reductions were observed from lower propeller loading noise. The propeller was also tested alone to investigate the behavior of the peak propeller noise with helical tip Mach number. As observed before on other propellers, the peak noise first rose with helical tip Mach number and then leveled off or decreased at higher helical tip Mach numbers. Detailed pressure-time histories indicate that a portion of the primary pressure pulse is progressively cancelled by a secondary pulse as the helical tip Mach number is increased. This cancellation appears to be responsible for the peak noise behavior at high helical tip Mach numbers
Detailed noise measurements on the SR-7A propeller: Tone behavior with helical tip Mach number
Detailed noise measurements were taken on the SR-7A propeller to investigate the behavior of the noise with helical tip Mach number and then to level off as Mach number was increased further. This behavior was further investigated by obtaining detailed pressure-time histories of data. The pressure-time histories indicate that a portion of the primary pressure pulse is progressively cancelled by a secondary pulse which results in the noise leveling off as the helical tip Mach number is increased. This second pulse appears to originate on the same blade as the primary pulse and is in some way connected to the blade itself. This leaves open the possibility of redesigning the blade to improve the cancellation; thereby, the propeller noise is reduced
Experiences in Multi-domain Management Service Development
The developers of management systems and the management services that operate over them will be faced with increasing complexity as services are developed for the open service market. This paper presents experiences in the development of management services that span several administrative domains and which are therefore representative of the complexities of the open service market. The work described involved the development of TMN based management systems that provided management services in support of multimedia teleservices operating over broadband networks
A new species of Colletes (Hymenoptera: Apoidea: Colletidae) from northern Florida and Georgia, with notes on the Colletes of those states
Colletes ultravalidus Hall & Ascher, new species, is described from several sites in northwestern Florida and southeastern Georgia. It is a member of the inaequalis species group, very similar to C. validus Cresson, a specialist of Ericaceae, but can be distinguished by an even more elongate malar area and the absence of conspicuous tergal fascia. Colletes ultravalidus has been found flying from early winter to early spring when it forms nest aggregations in xeric sites adjacent to shrub bog or basin swamp, the habitat of Pieris phyllyreifolia (Hook.) DC. (Ericaceae), the most likely, but as yet unconfirmed, host plant of the new species. State records of Colletes for Florida and Georgia are reviewed and discrepancies in taxonomy and distributional limits between Stephen’s 1954 revision of the genus and Mitchell’s 1960 monograph of eastern North American bees are noted. We concur with Stephen that the distributions of several taxa in Colletes are more limited than that reported by Mitchell
Exploiting multimedia in creating and analysing multimedia Web archives
The data contained on the web and the social web are inherently multimedia and consist of a mixture of textual, visual and audio modalities. Community memories embodied on the web and social web contain a rich mixture of data from these modalities. In many ways, the web is the greatest resource ever created by human-kind. However, due to the dynamic and distributed nature of the web, its content changes, appears and disappears on a daily basis. Web archiving provides a way of capturing snapshots of (parts of) the web for preservation and future analysis. This paper provides an overview of techniques we have developed within the context of the EU funded ARCOMEM (ARchiving COmmunity MEMories) project to allow multimedia web content to be leveraged during the archival process and for post-archival analysis. Through a set of use cases, we explore several practical applications of multimedia analytics within the realm of web archiving, web archive analysis and multimedia data on the web in general
Post-Issue Patent "Quality Control": A Comparative Study of US Patent Re-examinations and European Patent Oppositions
We report the results of the first comparative study of the determinants and effects of patent oppositions in Europe and of re-examinations on corresponding patents issued in the United States. The analysis is based on a dataset consisting of matched EPO and US patents. Our analysis focuses on two broad technology categories - biotechnology and pharmaceuticals, and semiconductors and computer software. Within these fields, we collect data on all EPO patents for which oppositions were filed at the EPO. We also construct a random sample of EPO patents with no opposition in these technologies. We match these EPO patents with the 'equivalent' US patents covering the same invention in the United States. Using the matched sample of USPTO and EPO patents, we compare the determinants of opposition and of re-examination. Our results indicate that valuable patents are more likely to be challenged in both jurisdictions. But the rate of opposition at the EPO is more than thirty times higher than the rate of re-examination at the USPTO. Moreover, opposition leads to a revocation of the patent in about 41 percent of the cases, and to a restriction of the patent right in another 30 percent of the cases. Re-examination results in a cancellation of the patent right in only 12.2 percent of all cases. We also find that re-examination is frequently initiated by the patentholders themselves.
Post-Issue Patent "Quality Control": A Comparative Study of US Patent Re-examinations and European Patent Oppositions
We report the results of the first comparative study of the determinants and effects of patent oppositions in Europe and of re- examinations on corresponding patents issued in the United States. The analysis is based on a dataset consisting of matched EPO and US patents. Our analysis focuses on two broad technology categories - biotechnology and pharmaceuticals, and semiconductors and computer software. Within these fields, we collect data on all EPO patents for which oppositions were filed at the EPO. We also construct a random sample of EPO patents with no opposition in these technologies. We match these EPO patents with the “equivalent” US patents covering the same invention in the United States. Using the matched sample of USPTO and EPO patents, we compare the determinants of opposition and of reexamination. Our results indicate that valuable patents are more likely to be challenged in both jurisdictions. But the rate of opposition at the EPO is more than thirty times higher than the rate of reexamination at the USPTO.
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