940 resultados para Renewall capability
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In this paper we present the results from the coverage and the orbit determination accuracy simulations performed within the recently completed ESA study “Assessment Study for Space Based Space Surveillance (SBSS) Demonstration System” (Airbus Defence and Space consortium). This study consisted in investigating the capability of a space based optical sensor (SBSS) orbiting in low Earth orbit (LEO) to detect and track objects in GEO (geosynchronous orbit), MEO (medium Earth orbit) and LEO and to determinate and improve initial orbits from such observations. Space based systems may achieve better observation conditions than ground based sensors in terms of astrometric accuracy, detection coverage, and timeliness. The primary observation mode of the proposed SBSS demonstrator is GEO surveillance, i.e. the systematic search and detection of unknown and known objects. GEO orbits are specific and unique orbits from dynamical point of view. A space-based sensor may scan the whole GEO ring within one sidereal day if the orbit and pointing directions are chosen properly. For an efficient survey, our goal was to develop a leak-proof GEO fence strategy. Collaterally, we show that also MEO, LEO and other (GTO,Molniya, etc.) objects would be possible to observe by the system and for a considerable number of LEO objects to down to size of 1 cm we can obtain meaningful statistical data for improvement and validation of space debris environment models
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AIM OF PAPER AND RESEARCH QUESTIONS The primary aim of this investigation was to examine, if tourism in Switzerland can be stimulated by focusing on e-bike offers. Switzerland is an attractive and manifold country for bike tourism. However, there are plenty of hilly and steep areas, where the topography is quite demanding and cycling is predestined to ambitious sportsperson. Less performance-oriented bike tourists are possibly discouraged by the challenges of the landscape. E-bikes seem to be a reasonable alterna-tive to enable less trained person to attend bike tours in steeper regions as well as to keep heterogeneous groups together. E-bikes are already popular in Switzerland for daily routes as the journey to work, but they are not very common in the tour-istic context. The presented investigation evaluates the current standing of supply and demand for e-bike tourism and asks for opportunities and threats in the future development. LITERTURE REVIEW The existing frameworks to analyse capability in the field of sport tourism are limited, because of the broad variation of sports and tourism types. Still several conceptions are valuable to evaluate the opportunities of e-bike tourism in Switzer-land. According to Higham and Hinch (2009) the potential of touristic products and destinations always depends on the interaction among the factors place, people and activity. Standeven and de Knop (1999) support this position by identify-ing the experience of place as a key component of the sport tourism experience. Bull (2005) assumes that place not only affects experience. In his opinion, the specific spatially located resources are even crucial for the existence of nature sports. He identifies four factors determining the attraction of touristic products or destination, as physical characteristics, accessibility and infrastructural arrangements, political and economic resources as well as cultural and perceptual aspects. Concerning the demand side (people) the contemporary research is guided by an individual psychological focus delivering mainly results about motives and the decision making process (e.g. Görtz & Hürten, 2011). RESEARCH DESIGN AND DATA ANALYSIS The presented study is based on a between method triangulation, consisting of qualitative interviews with important stake-holders on the supply side and a cross sectional survey on the demand side. Qualitative interviews were conducted with the first provider of touristic e-bike routes and with the manager of the leading e-bike rental company in Switzerland. The interviews were evaluated by qualitative content analysis according to Mayring (2008). The survey covered a randomized sample of 748 adult persons and focused on interests and needs of potential consumers. The concluding potentials analy-sis combined the results of the interviews and the survey with the findings of literature research. As central outcome the strengths, weaknesses, opportunities and threats were evaluated and presented by SWOT-analysis. RESULTS Results showed that the development of e-bike tourism in Switzerland was not initiated by tourism promoter, but by an innovative e-bike producer. However, also for the manufacturer the fit between landscape (place), product (activity) and visitors (people) was the crucial criterion. The first e-bike tours were offered in a demanding and rural region, in order that the experience of place was able to promote a positive overall experience. Due to the success of the first touristic e-bike products, several tourism regions started to extend their portfolio with e-bike offers. To date a nationwide network for signalised e-bike tours, rental stations and changing stations for rechargeable batteries is established. Despite the attractive offer, the demand is only moderate. The obtained results of the consumer survey pointed at a certain barrier to use e-bikes for tourism activities. The most substantial barrier is the missing affinity for bike tourism in general. Another notable group considering themselves as “fit enough for normal bike tourism”. Nevertheless 55% of the respondent are interested in tour-istic e-bike products. Looking only at people with e-bike tourism experience, even 92% are interested in further activities. DISCUSSION AN CONCLUSION The current study findings are encouraging because they suggest a superior suitability and an attractive level of e-bike tourism products in Switzerland. The results of the consumer survey indicate an increasing demand for e-bike tourism. The investigation also points at some risks, as the rivalry for bike tourism or the raised safety hazard because of the increased driving speed. Summing up, the results support the conclusion, that e-bike tourism will become more important in the com-ing years. However, to reach the goal relevant trends as the requirement for customised offers must be considered and marketing activities are supposed to be extended. REFERENCES Bull, C. (2005). Sport tourism resource analysis. In J. Higham (Ed.), Sport tourism destination: Issues, opportunities and analysis (pp. 25-38). Amsterdam: Elsevier Butterworth-Heinemann. Görtz, M., & D. Hürten (2011). Motive der Radurlauber, psychografische Merkmale und Reiseverhalten. In A. Dreyer, E. Miglbauer & R. Mühlnickel (Hrsg.), Radtourismus. Entwicklungen, Potenziale, Perspektiven (S. 36-43). München: Olden-bourg. Higham, J., & Hinch, T. (2009). Sport and Tourism. Globalization, Mobility and Identity. Amsterdam: Butterworth-Heinemann. Mayring, P. (2008). Qualitative Inhaltsanalyse. Grundlagen und Techniken (10. Aufl.). Weinheim: Beltz Verlag. Standeven, J., & De Knop, P. (1999). Sport Tourism. Campaign: Human Kinetics.
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The importance of organizing local people for development work is widely recognized. Both governmental and non-governmental agencies have implemented various projects that have needed and encouraged collective action by people. Often, however, such projects malfunction after the outside agencies retreat from the project site, suggesting that making organizations is not the same as making a system of making organizations. The latter is essential to make rural organizations self-reliant and sustainable. This paper assumes that such a system exists in local societies and focuses on the capacity of local societies for creating and managing organizations for development. It reveals that (1) such capability differs according to the locality, (2) the difference depends on the structure of the organizations that coordinate people's social relations, and (3) the local administrative bodies define, at least partly, the organizational capability of local societies. We compare two rural societies, one in Thailand and the other in the Philippines, which show clear contrasts in both the form of microfinance organizations and the way of making these organizations.
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This paper develops a Capability Matrix for analyzing capabilities of developing country firms that participate in global and national value chains. This is a generic framework to capture firm-level knowledge accumulation in the context of global and local industrial constellations, by integrating key elements of the global value chain (GVC) and technological capabilities (TC) approaches. The framework can visually portray characteristics of firms’ capabilities, and highlight a relatively overlooked factor in the GVC approach: local firms’ endogenous learning efforts in varieties of relationship with lead firms.
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Environmental constraints imposed on hydropoweroperation are usually given in the form of minimum environmental flows and maximum and minimum rates of change of flows, or ramp rates. One solution proposed to mitigate the environmental impact caused by the flows discharged by a hydropower plant while reducing the economic impact of the above-mentioned constraints consists in building a re-regulationreservoir, or afterbay, downstream of the power plant. Adding pumpingcapability between the re-regulationreservoir and the main one could contribute both to reducing the size of the re-regulationreservoir, with the consequent environmental improvement, and to improving the economic feasibility of the project, always fulfilling the environmental constraints imposed to hydropoweroperation. The objective of this paper is studying the contribution of a re-regulationreservoir to fulfilling the environmental constraints while reducing the economic impact of said constraints. For that purpose, a revenue-driven optimization model based on mixed integer linear programming is used. Additionally, the advantages of adding pumpingcapability are analysed. In order to illustrate the applicability of the methodology, a case study based on a real hydropower plant is presented
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Positive composite electrodes having LiNi0.5Mn1.5O4 spinel as active material, a blend of graphite and carbon black for increasing the electrode electrical conductivity and either polyvinyldenefluoride (PVDF) or a blend of PVDF with a small amount of Teflon® (1 wt%) for building up the electrode. They have been processed by tape casting on an aluminum foil as current collector using the doctor blade technique. Additionally, the component blends were either sonicated or not, and the processed electrodes were compacted or not under subsequent cold pressing. Composites electrodes with high weight, up to 17 mg/cm2, were prepared and studied as positive electrodes for lithium-ion batteries. The addition of Teflon® and the application of the sonication treatment lead to uniform electrodes that are well-adhered to the aluminum foil. Both parameters contribute to improve the capacity drained at high rates (5C). Additional compaction of the electrode/aluminum assemblies remarkably enhances the electrode rate capabilities. At 5C rate, remarkable capacity retentions between 80% and 90% are found for electrodes with weights in the range 3–17 mg/cm2, having Teflon® in their formulation, prepared after sonication of their component blends and compacted under 2 tonnes/cm2.
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The Internet of Things makes use of a huge disparity of technologies at very different levels that help one to the other to accomplish goals that were previously regarded as unthinkable in terms of ubiquity or scalability. If the Internet of Things is expected to interconnect every day devices or appliances and enable communications between them, a broad range of new services, applications and products can be foreseen. For example, monitoring is a process where sensors have widespread use for measuring environmental parameters (temperature, light, chemical agents, etc.) but obtaining readings at the exact physical point they want to be obtained from, or about the exact wanted parameter can be a clumsy, time-consuming task that is not easily adaptable to new requirements. In order to tackle this challenge, a proposal on a system used to monitor any conceivable environment, which additionally is able to monitor the status of its own components and heal some of the most usual issues of a Wireless Sensor Network, is presented here in detail, covering all the layers that give it shape in terms of devices, communications or services.
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Reactive oxygen intermediates (ROI) play a critical role in the defense of plants against invading pathogens. Produced during the “oxidative burst,” they are thought to activate programmed cell death (PCD) and induce antimicrobial defenses such as pathogenesis-related proteins. It was shown recently that during the interaction of plants with pathogens, the expression of ROI-detoxifying enzymes such as ascorbate peroxidase (APX) and catalase (CAT) is suppressed. It was suggested that this suppression, occurring upon pathogen recognition and coinciding with an enhanced rate of ROI production, plays a key role in elevating cellular ROI levels, thereby potentiating the induction of PCD and other defenses. To examine the relationship between the suppression of antioxidative mechanisms and the induction of PCD and other defenses during pathogen attack, we studied the interaction between transgenic antisense tobacco plants with reduced APX or CAT and a bacterial pathogen that triggers the hypersensitive response. Transgenic plants with reduced capability to detoxify ROI (i.e., antisense APX or CAT) were found to be hyperresponsive to pathogen attack. They activated PCD in response to low amounts of pathogens that did not trigger the activation of PCD in control plants. Our findings support the hypothesis that suppression of ROI-scavenging enzymes during the hypersensitive response plays an important role in enhancing pathogen-induced PCD.
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The posttranslational modification of eukaryotic intracellular proteins by O-linked N-acetylglucosamine (O-GlcNAc) monosaccharides is essential for cell viability, yet its precise functional roles are largely unknown. O-GlcNAc transferase utilizes UDP-GlcNAc, the end product of hexosamine biosynthesis, to catalyze this modification. The availability of UDP-GlcNAc correlates with glycosylation levels of intracellular proteins as well as with transcriptional levels of some genes. Meanwhile, transcription factors and RNA polymerase II can be modified by O-GlcNAc. A linkage between transcription factor O-GlcNAcylation and transcriptional regulation therefore has been postulated. Here, we show that O-GlcNAcylation of a chimeric transcriptional activator containing the second activation domain of Sp1 decreases its transcriptional activity both in an in vitro transcription system and in living cells, which is in concert with our observation that O-GlcNAcylation of Sp1 activation domain blocks its in vitro and in vivo interactions with other Sp1 molecules and TATA-binding protein-associated factor II 110. Furthermore, overexpression of O-GlcNAc transferase specifically inhibits transcriptional activation by native Sp1 in cells. Thus, our studies provide direct evidence that O-GlcNAcylation of transcription factors is involved in transcriptional regulation.
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Infectious human respiratory syncytial virus (RSV) was produced by the intracellular coexpression of five plasmid-borne cDNAs. One cDNA encoded a complete positive-sense version of the RSV genome (corresponding to the replicative intermediate RNA or antigenome), and each of the other four encoded a separate RSV protein, namely, the major nucleocapsid N protein, the nucleocapsid P phosphoprotein, the major polymerase L protein, or the protein from the 5' proximal open reading frame of the M2 mRNA [M2(ORF1)]. RSV was not produced if any of the five plasmids was omitted. The requirement for the M2(ORF1) protein is consistent with its recent identification as a transcription elongation factor and confirms its importance for RSV gene expression. It should thus be possible to introduce defined changes into infectious RSV. This should be useful for basic studies of RSV molecular biology and pathogenesis; in addition, there are immediate applications to the development of live attenuated vaccine strains bearing predetermined defined attenuating mutations.
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Light sources with three spectral bands in specific spectral positions are known to have high-color-discrimination capability. W. A. Thornton hypothesized that they may also enhance color discrimination for color-deficient observers. This hypothesis was tested here by comparing the Rösch–MacAdam color volume for color-deficient observers rendered by three of these singular spectra, two reported previously and one derived in this paper by maximization of the Rösch–MacAdam color solid. It was found that all illuminants tested enhance discriminability for deuteranomalous observers, but their impact on other congenital deficiencies was variable. The best illuminant was the one derived here, as it was clearly advantageous for the two red–green anomalies and for tritanopes and almost neutral for red–green dichromats. We conclude that three-band spectra with high-color-discrimination capability for normal observers do not necessarily produce comparable enhancements for color-deficient observers, but suitable spectral optimization clearly enhances the vision of the color deficient.
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Resorcinol-Formaldehyde xerogels are organic polymers that can be easily tailored to have specific properties. These materials are composed of carbon, hydrogen and oxygen, and have a surface that is very rich in oxygen functionalities, and is therefore very hydrophilic. Their most interesting feature is that they may have the same chemical composition but a different porous texture. Consequently, the influence of porous characteristics, such as pore volume, surface area or pore size can be easily assessed. In this work, a commonly used desiccant, silica gel, is compared with organic xerogels to determine their rate and capacity of water adsorption, and to evaluate the role of surface chemistry versus porous texture. It was found that organic xerogels showed a higher rate of moisture adsorption than silica gel. Pore structure also seems to play an important role in water adsorption capacity. The OX-10 sample, whose porosity was mainly composed of micro-mesoporosity displayed a water adsorption capacity two times greater than that of the silica gel, and three times higher than that of the totally macroporous xerogel OX-2100. The presence of feeder pores (mesopores) that facilitate the access to the hydrophilic surface was observed to be the key factor for a good desiccant behaviour. Neither the total pore volume nor the high surface area (i.e. high microporosity) of the desiccant sample, is as important as the mesopore structure.