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141.
142.
Many Fourier transform applications have to operate at fixed sample rates in the low to medium range, especially in signal processing systems. Hence, in order to arrive at efficient implementations, hardware-sharing is required as in microcoded architectures. In this paper, very efficient application-specific realizations spanning a wide throughput range are proposed for both DFT and FFT algorithms. Novel single-cycle address computations are presented for the FFT to obtain these results. Trade-offs between the architectural alternatives are provided too. These designs have been used as test-vehicles for the architectural strategy in an automated synthesis tool-box tuned towards signal processing applications.This research has been sponsored in part within the context of the ESPRIT97 project by the EC and the industrial partners Philips, Siemens, BTMC/Alcatel and Silvar/Lisco. 相似文献
143.
Technological innovation and regional economic growth in Mexico: a spatial perspective 总被引:1,自引:0,他引:1
Víctor Hugo Torres-Preciado Mayrén Polanco-Gaytán Miguel Á. Tinoco-Zermeño 《The Annals of Regional Science》2014,52(1):183-200
The aim of this investigation is to analyze the effect of technological innovation on Mexico’s regional economic growth during 1995–2007. It is argued that the inclusion of the spatial dimension in empirical analysis is still a rare practice in Mexico and even in international studies. Such inclusion allows studying the pattern of spatial interaction, the possible effects of spatial diffusion and the estimation of robust parameters. We apply the spatial data analysis methodology that has three components: (a) exploratory analysis, (b) visualization and (c) spatial econometric modeling. The main result suggests that technological innovation has a positive effect on Mexico’s regional economic growth. The empirical evidence also suggests that there is a positive effect coming from cross-border diffusion effects of technological knowledge. It also implies that states with stronger innovation activity benefited from spatial technological externalities and hence faster economic growth. 相似文献
144.
Mathias Kersemans Arvid Martens Koen Van Den Abeele Joris Degrieck Filip Zastavnik Lincy Pyl Hugo Sol Wim Van Paepegem 《Journal of Nondestructive Evaluation》2014,33(4):522-534
In this paper, the hybrid compliance-stiffness matrix method for simulating wave propagation in (delaminated) multilayered media with viscoelastic anisotropy has been confronted with high-quality amplitude and phase experiments on delaminated composites, obtained using the ultrasonic polar scan setup (UPS) in transmission by considering harmonic as well as pulsed ultrasound. Results are presented for multiple thin carbon/epoxy laminates with an artificial edge delamination induced by a foil insert, showing a good agreement between experimental recording and numerical modeling. The obtained results further reveal the feasibility of the harmonic UPS to detect and even locate the depth-position of multiple delaminations in fiber reinforced composites. Considering that the harmonic UPS method does not rely on the detection of different echoes like the classical C-scan, but rather expounds the conditions for efficient stimulation of guided waves in the solid, the method is found to be highly suited for inspecting thin composite materials for the presence of delaminations. 相似文献
145.
Aarts HJ Vos P Larsson JT van Hoek AH Huehn S Weijers T Grønlund HA Malorny B 《International journal of food microbiology》2011,145(Z1):S68-S78
A proof of principle of a multi-target assay for genotyping Salmonella has been developed targeting 62 genomic marker sequences of Salmonella related to pathogenicity. The assay is based on multiplex ligation detection reaction (LDR) followed by customized ArrayTube? microarray detection. The feasibility of the developed assay was verified in a method comparison study with conventional PCR using 16 Salmonella 'test' strains comprising eight serovars. Subsequently, the feasibility of the LDR microarray assay was also tested by analyzing 41 strains belonging to 23 serovars. With the exception of four serovars each serovar was characterized by a unique virulence associated gene repertoire. The LDR microarray platform proved to be a convenient, rapid and easy to use tool with potential in tracing a Salmonella contamination in the food chain, for outbreak studies, and to provide data for risk assessors that support bio-traceability models. 相似文献
146.
Klaus Nolte Alexandros Kaloxylos Kostas Tsagkaris Thomas Rosowski Makis Stamatelatos Aristi Galani Eckard Bogenfeld Panagis Magdalinos Jens Tiemann Jens Gebert Paul Arnold Dirk von Hugo Nancy Alonistioti Panagiotis Demestichas Wolfgang Koenig 《International Journal of Network Management》2011,21(5):360-383
Future mobile networks are expected to be complex heterogeneous systems. On the one hand this will enable users to take advantage of a number of different access technologies. On the other hand it will seriously affect network management procedures since more extensive operations and decisions will have to be dealt with. To tackle these challenges a number of new dynamic mechanisms need to be designed. It is imperative that certain network management tasks have to be performed without human intervention to reduce the OPEX costs and achieve faster responses in different events. To achieve this goal, the introduction of self‐x functionalities, combined with cognitive mechanisms and the ability to reconfigure network entities and terminals, is required. Moreover, the introduction of a new pilot channel needs to be considered to assist the terminals in selecting the most suitable radio access technology according to their requirements. We present the functional architecture of an evolved network that was designed in the context of the EU‐funded IP project ‘E3: End‐to‐End Efficiency’. This architecture aims to enhance existing procedures usually performed in traditional operation and maintenance systems (e.g. spectrum management, network planning, configuration actions). We explain the rationale of our design and provide specific examples to illustrate the role of the different functional entities and their interfaces. A considerable part of this architecture has recently been approved as a feasibility study by the ETSI Committee Reconfigurable Radio System. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
147.
Argentine water resources are located in three hydrologically contrasting regions: the so-called Del Plata basin, the Arid Central Andean area, and Patagonia. About 150 dams and impounding reservoirs that exceed a capacity of 150 × 103 m3, have been built. Most limnological studies of regulated rivers have been conducted recently. In the Del Plata basin, Argentine dams are scarce, although many have been built or are projected upstream, mainly in Brazil. The ecological problems of the reservoirs are related to decomposition of inundated terrestrial vegetation; algae blooms, dissolved oxygen depletion phenomena, eutrophication, impaired fish migrations, overproduction of water hyacinth Eichhornia spp., and schistosomiasis. The importance of examining the influence of the projected middle Paraná dams on downstream sediment regimes, especially as it affects the delta, is emphasized. In the Arid or Central Andean region, the main development of the Grande-Tercero rivers includes dams, reservoirs, and the operation of a nuclear power plant. One of the most important effects will be a slight increase in the water temperature of the Rio Tercero reservoir as a consequence of water use in the cooling system of the nuclear power plant. In the Patagonian region, the main dams are those built and projected for the Colorado and Negro basins. In the Negro basin studies are being carried out mainly in the Ramos Mexia Reservoir, on different aspects of zooplankton and phytoplankton, benthos, and fishes. Commercial fishing is not permitted and fishing is based mainly on the introduced salmonids which show symptoms of undernourishment because of a lack of forage fishes. Indigenous fishes have been decimated by the introduced salmonids. Although studies have been conducted in several areas, much work remains to be done in relation to the environmental effects of dams on streams in Argentina. Results from ecological studies are still insufficient to solve the multiple problems associated with them, such as climatic influences, retention of suspended solids, deforestation, schistosomiasis and other aquatic diseases, pollution, eutrophication, fish-ways and fish migrations, accumulations of the water-hyacinth, salt and nutrient regimes, and siltation. Even partial solutions to these problems will require an ensemble of urgent measures to assure the maximum benefits with minor risks and ecological costs. 相似文献
148.
Levels of social housing investment in the UK and the Netherlands are considered for the period 1970–1992. The changing housing
policies and the developing structures of social housing finance are analysed. These factors have contributed to the decline
in social housing construction in the UK and the Netherlands. In particular, the desire of governments in both countries to
cut public capital expenditure on housing and increase the role of private, capital in new construction reduced the output
during the 1980s. In the UK, a tight monetarist policy was adopted with the aim of keeping inflation down. This can be seen
as a major cause of declining levels of public expenditure on housing production. In the Netherlands, a more significant role,
compared to the UK, seems to have been played by developments on the housing market, especially the real estate crisis in
1978–1982. In both countries, the outlook for investment in social housing is gloomy
Hugo Priemus hold the chair in housing at Delft Unviersity of Technology, and he is managing director of OTB Research Institute
for Policy and Technology
Jacqueline Smith is research assistant at the School of the Built Environment, De Montfort University, Leicester, (UK).
Both cooperate in the Centre for Comparative Housing Research, a joint venture between the School of the Built Environment
and OTB. 相似文献
149.
Stocker Clare M.; Burwell Rebecca A.; Briggs Megan L. 《Canadian Metallurgical Quarterly》2002,16(1):50
Associations between sibling conflict in middle childhood and psychological adjustment in early adolescence were studied in a sample of 80 boys and 56 girls. Parents and children provided self-report data about family relationships and children's adjustment. Parents' hostility to children was assessed from videotaped interactions. Results showed that sibling conflict at Time 1 predicted increases in children's anxiety, depressed mood, and delinquent behavior 2 years later. Moreover, earlier sibling conflict at Time 1 accounted for unique variance in young adolescents' Time 2 anxiety, depressed mood, and delinquent behavior above and beyond the variance explained by earlier maternal hostility and marital conflict. Children's adjustment at Time 1 did not predict sibling conflict at Time 2. Results highlight the unique significance of the earlier sibling relationship for young adolescents' psychological adjustment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
150.
Hugo Mühlcker 《化学,工程师,技术》1989,61(6):453-459
Scope and problem solutions of power generation by wind-driven plant. The importance of wind power has changed in the course of history with the advent of competing energy converters for power production from coal, oil, and nuclear energy. The known physical laws of aerodynamics and geographical location ascribe wind power a market share of no more than a few percent of power generation. Among the many designs of wind turbines, only 2- and 3-blade propeller turbines have been produced in large quantities with power ratings up to ca. 4 MW. Market developments have so far been determined by government funding. The power generation costs of 0.25 to 0.30 DM/kWh are still too high by a factor of 2 to 3. With regard to future developments it remains to be seen whether the use of more sophisticated generator systems will permit the expected large savings on the mechanical side and thus open the path to economic large production runs also in the case of medium and large-scale units. 相似文献