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1.
Conclusion A successful informal sector of sustainable ICT clusters requires that the ICT provided are the ones in demand by the entrepreneurs
and that they should be located strategically, in order to generate optimal utilisation and avoid the loss of man-hours by
the informal sector having to search for the services. There should also be a strategy aiming at investment in human capital,
which will trigger active absorption of skills and technology. This calls for a collaboration or partnership between government
and other development partners, especially those who can facilitate training in business development and management skills,
as well as the use of ICT. A special focus of this ICT strategy should be to demystify and promote diffusion of ICT as a general-purpose
technology to the informal sector.
It is believed that the use of new technologies can be crucial to meeting the Millennium Development Goals (MDGs) in a timely
and effective fashion. In response to this noble call the study concludes that there is a need to prevent further marginalization
of the informal sector by availing ICT services which are mixed appropriately and also properly located. This will help them
access markets and other business information which can enable, or make their economic activities, more vibrant and facilitate
availability of information about new opportunities. The study concludes that for one to understand the application of ICT
and their locational dynamics in informal sector clusters there is a need to comprehend and acknowledge the drivers and pressures
leading to the adoption of new technology such as ICT in the informal sector. 相似文献
2.
Scalart P. Leclerc M. Fortier P. Huu Tue Huynh 《Broadcasting, IEEE Transactions on》1997,43(2):191-198
In this paper, we present a performance analysis of a coded orthogonal frequency division multiplexing DAB system that is power multiplexed over a commercial FM station. We model the mobile channel with a time-frequency scattering function. Results show that the performance of the FM demodulator is crucial, since the level of the residual FM signal has a strong influence on the BER performance of the COFDM system. As with other mobile communication systems, the use of interleaving greatly enhances the performances 相似文献
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4.
Natasja Leth Bergholt Ari Demirel Michael Pedersen Ming Ding Tue Wenzel Kragstrup Thomas Andersen Bent Winding Deleuran Casper Bindzus Foldager 《International journal of molecular sciences》2022,23(1)
Systemic Intermittent Hypoxic Therapy (IHT) relies on the adaptive response to hypoxic stress. We investigated allogenic bone-graft resorption in the lumbar spine in 48 mice. The mice were exposed to IHT for 1 week before surgery or 1 week after surgery and compared with controls after 1 and 4 weeks. Complete graft resorption was observed in 33–36% of the animals in the control group, but none in the preoperative IHT group. Increased bone-graft volume was demonstrated by micro-computed tomography in the preoperative IHT group after 1 week (p = 0.03) while a non-significant difference was observed after 4 weeks (p = 0.12). There were no significant differences in the postoperative IHT group. Increased concentration of immune cells was localized in the graft area, and more positive tartrate-resistant acid phosphatase (TRAP) staining was found in controls compared with IHT allogenic bone grafts. Systemic IHT resulted in a significant increase of the major osteoclast inhibitor osteoprotegerin as well as osteogenic and angiogenic regulators Tgfbr3, Fst3l, Wisp1, and Vegfd. Inflammatory cytokines and receptor activator of nuclear factor kappa-B ligand (RANKL) stimulators IL-6, IL-17a, IL-17f, and IL-23r increased after 1 and 4 weeks, and serum RANKL expression remained constant while Ccl3 and Ccl5 decreased. We conclude that the adaptive response to IHT activates numerous pathways leading to inhibition of osteoclastic activity and inhibition of allogenic bone-graft resorption. 相似文献
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6.
Experimental studies have been carried out about the particle separation performance of single and two inlets hydrocyclones. Two types of hydrocyclones having the same total inlet holes area were examined. Hydrocyclone A (with single inlet hole) and hydrocyclone B (with two inlet holes) were used. An aqueous slurry of silica particles (0.5 wt% with a median diameter of about 2.1 μm) was tested using a 20 mm-diameter hydrocyclone with a 15% underflow ratio. It was found that the optimum flow rate which gives the highest separation performance of the hydrocyclone B is the same flow rate for each inlet. Usage of the hydrocyclone B indicated smaller cut size and higher particle collection efficiency compared to that of the hydrocyclone A, under the same flow rate or same pressure drop conditions. The time of flight model was used to predict the 50% cut size diameter for single inlet hydrocyclone, and the model was modified to the two inlets hydrocyclone. It was found that the calculated results agree well with the experimental results for the hydrocyclone A, and for the hydrocyclone B under the low total flow rates conditions. 相似文献
7.
Crack width control according to Eurocode 2 – Explanatory notes on factor k c Reinforced concrete members are designed now according to EC2 [1]. A significant aspect is the determining of the minimum reinforcement area specified in section 7.3.2. Due to the shortened illustrations of the equations (7.1) and (7.2), the mechanical background is difficult to be highlighted. This often results in inaccurate use of the model parameters, which might lead to an unsafe design, particularly for members predominantly reinforced only by the minimum reinforcement. Therefore the mechanical background of the equations (7.1) and (7.2) is focused on in this contribution. Proper discussions and explanations might help the structural engineer in the practical design. 相似文献
8.
论我国大城市中高校校园建设的走向 总被引:1,自引:0,他引:1
一座城市,尤其是具有悠久文脉的大城市,都会有一些著名的高等学府。本世纪末,随着我国城市化进程加快,城市品质不断提高,城市中原有的大学校园已远远不适应新世纪的教学、科研等多方面需求,形成了近几年高校校园改、扩建的浪潮。本文在我国跨世纪高校校园建设发展的走向,以及高等学府在城市中地位等问题上阐述了自己的观点。 相似文献
9.
Peter Schaaf Prof. Dr. Lothar Spieß Prof. Thomas Kups Dr. Henry Romanus Dr. Rolf Grieseler Marcus Hopfeld Marcus Wilke Thomas Stauden Dr. David Lorenz Andreas Fischer 《真空研究与实践》2011,23(3):24-32
Films over films: innovative coatings for complex applications Thin films and coatings have developed as a prerequisite for many technical applications. In this paper, some applications for electrical, electronic, biomedical and optical applications are presented. In this contribution, examples for coatings for conductive and transparent films in photovoltaics, films for biomedical electrodes, for semiconductor contacts and for high‐temperature contacts are presented and discussed. The films are prepared by magnetron‐sputtering and pulsed laser deposition. The influence of the processing parameters on the functional properties of the films is presented. 相似文献
10.
Chunyu Wang Volker Cimalla Genady Cherkashinin Henry Romanus Majdeddin Ali Oliver Ambacher 《Thin solid films》2007,515(5):2921-2925
We have grown indium oxide thin films on silicon substrates at low temperature by metal organic chemical vapor deposition. Polycrystalline film growth could only be obtained at temperatures below 400 °C. Above 400 °C, metallic indium deposition dominated. We have investigated the effect of substrate temperature and reactor pressure on the film growth and structural properties in the range of 250-350 °C and 5 ? 103-4 ? 104 Pa. The film grown at 300 °C exhibited a resistivity of about 3.6 × 10− 3 Ω cm and a maximal optical transmittance of more than 95% in the visible range. The film showed an optical band gap of about 3.6 eV. 相似文献