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71.

In rural areas, depopulation is mainly due to a lack of economic and employment opportunities. In this context, the reservoirs already built can be a source of socioeconomic development based on tourism and outdoor leisure activities. The condition for this development to materialize is that reservoir management considers these activities. In Central Spain, a process of rural depopulation has been generated in the municipalities around the reservoirs at the Upper Tagus River, as water management allows water transfers from the Tagus to the Segura River without taking into account regulations that prioritize and protect donor basin users. Through the comparison of reservoir water management and demographic data of two rural areas close to the reservoirs, this article reveals the direct relationship between reservoir management that enables recreational uses with its consequent socioeconomic development and the maintenance of the population in the territory. Consequently, reservoir water management based on the socioeconomic development of reservoir banks is necessary and a priority over transfers to another basin.

  相似文献   
72.
The impact of waste disposal on marsh soils was assessed in topsoil samples collected at eight randomly selected points in the salt marsh in Ramallosa (Pontevedra, Spain) at 4-month intervals for 2 years. Polluted soil samples were characterized in physico-chemical terms and their heavy metal contents determined by comparison with control, unpolluted samples. The results revealed a marked effect of waste discharges on the soils in the area, which have low contents in heavy metals under normal environmental conditions. In fact, the studied soils were found to contain substantial amounts of total and DTPA-extractable Cd, Cu, Pb and Zn. Based on the relationship of the redox potential with the DTPA-extractable Cd, Cu, Pb, and Zn contents of the soils, strongly reductive conditions raised the total contents in these elements by effect of their remaining in the soils as precipitated sulphides. Such contents, however, decreased as oxidative conditions gradually prevailed. The contents in DTPA-extractable metals increased with increasing Eh through the release of the metals in ionic form to the soil solution under oxidative conditions. The contents in heavy metals concentrating in the polluted soils were several times higher than those in the control soils (viz. 2 vs. 6 for Cd, 4 vs. 6 for Cu, 4 vs. 20 for Pb, and 2 vs. 15 for Zn, all in mg kg−1). This can be expected to influence the amounts of available heavy metals present in the soils, and hence the environmental quality of the area, in the near future. Based on its geoaccumulation index (Class ≥3 for Cd and Cu, and 1–4 for Pb and Zn), the Ramallosa marsh is highly polluted with Cd and moderately to highly polluted with Cu, Pb and Zn. The enrichment factors obtained confirm that the salt marsh is highly polluted (especially with Cd) as the primary result of anthropic activity.  相似文献   
73.
Software is a major source of reliability degradation in dependable systems. One of the classical remedies is to provide software fault tolerance by using N-Version Programming (NVP). However, due to requirements on non-standard hardware and the need for changes and additions at all levels of the system, NVP solutions are costly, and have only been used in special cases.In a previous work, a low-cost architecture for NVP execution was developed. The key features of this architecture are the use of off-the-shelf components including communication standards and that the fault tolerance functionality, including voting, error detection, fault-masking, consistency management, and recovery, is moved into a separate redundancy management circuitry (one for each redundant computing node).In this article we present an improved design of that architecture, specifically resolving some potential inconsistencies that were not treated in detail in the original design. In particular, we present novel techniques for enforcing replica determinism.Our improved architecture is based on using the Controller Area Network (CAN). This choice goes beyond the obvious interest of using standards in order to reduce the cost, since all the rest of the architecture is designed to take full advantage of the CAN standard features, such as data consistency, in order to significantly reduce the complexity, the efficiency and the cost of the resultant system.Although initially developed for NVP, our redundancy management circuitry also supports other software replication techniques, such as active replication.  相似文献   
74.
The one‐pot synthesis and properties of multifunctional hybrid mesoporous organosilica fibers with helical shapes are described. These hybrid mesoporous fibers are prepared without chiral elements and functionalized with a large variety of organic R functions (R = alkylthiols, phenylsulfonates, alkylphosphonates, dansyl, aminopropyl, fluoroalkyl, etc.). The resulting nanomaterials are thoroughly characterized by a variety of techniques. The use of a synergetic combination of achiral molecules as co‐directing structuring agents, a surfactant, and an organofunctional silica precursor R‐Si(OR)3 allows, via carefully tuning of the main synthesis parameters and processing conditions, to control the shape, which is the anisotropic factor, of the hybrid nanofibers. The functionalization of the hybrid materials with fluorescent molecules (dansyl) and gold nanoparticles opens possibilities for sensor and catalytic applications, respectively. Moreover, these hybrid nanofibers can be easily transferred in organic solvents or in a “green” solvent such as water to make stable colloidal dispersions. This tunable functionality of nanofibers also allows their transferability into a variety of polymeric hosts (PVDF, PVBu, and PVP) allowing the formation of functional homogeneous nanocomposite hybrid membranes.  相似文献   
75.
Most color image sensors use color filter arrays (CFA). With this sensor design the captured information at each sensor pixel position is restricted to a specific spectral portion (typically red, green and blue bands). To obtain the missing color responses at each pixel position, so-called CFA demosaicing algorithms are commonly used. We propose two new CFA demosaicing algorithms, which are well suited for industrial print inspection with respect to the requirements in accuracy and speed. As a main contribution, we introduce novel demosaicing algorithms for specific high-speed color digital time delay and integration (DTDI) CFA line-scan cameras. We compare the suggested CFA demosaicing algorithms to state-of-the art algorithms for area and line-scan camera operation modes. We show that the two new algorithms perform superior to conventional algorithms as indicated by reconstruction error.  相似文献   
76.
Vacuum skin packaging (VSP) is a new and promising technology that includes the instantaneous heating of the upper packaging film immediately before its descent over the meat surface. In the present paper we evaluated this technology for the packaging of a wide variety of beef retail cuts and compared this with traditional vacuum packaging (TVP) performed in parallel. Shelf-life and quality evolution was estimated by analysing three spoilage bacterial groups, an ubiquitous psychrotrophic food pathogen, and three biochemical and physico-chemical attributes throughout 40 days of storage at 4 °C. Statistically-significant lower microbial counts were obtained for all microbial parameters and meat types. The VSP lot exhibited lower pH. This, however, involved a lower water holding capacity and a higher degree of firmness, the latter indicating a limited tenderisation process in the VSP batch. Extended aging times in the carcasses were studied to improving the tenderness of VSP samples. The extension of the aging process prior to VSP may be useful for improving the tenderness of certain meat types and to improve the sensory quality of meat cuts processed under this system.  相似文献   
77.
Various techniques for the extraction of ANN rules have been used, but most of them have focused on certain types of networks and their training. There are very few methods that deal with ANN rule extraction as systems that are independent of their architecture, training, and internal distribution of weights, connections, and activation functions. This article proposes a methodology for the extraction of ANN rules, regardless of their architecture, and based on genetic programming. The strategy is based on the previous algorithm and aims at achieving the generalization capacity that is characteristic of ANNs by means of symbolic rules that are understandable to human beings.  相似文献   
78.
In this paper we present an integrated circuit implementing piecewise-linear (PWL) functions with three inputs, where each input can be either analog or digital. The PWL function to be implemented can be chosen by properly storing a set of coefficients in a 4 kB external memory. Experimental results are shown that demonstrate the circuit working up to 50 MHz with a maximum power consumption of 3.7 mW. Measurements corresponding to both static and time-varying inputs are provided and discussed.  相似文献   
79.
On May 4th,2006,the international publication of a patentapplicationtitled“alloyed zinc powders for alkaline batteries withhigh Pyknometer density”WO2006/045470 A1[1],appeared·Theintention of this investigation was to see whether it is possible torepro…  相似文献   
80.
本论述了我国高职高专教育教学工作实验全面质量管理(TQC)的意义和其在高职高专教育教学工作中的应用,并对如何应用全面质量管理,提高高职高专教育教学工作水平谈了几点看法。  相似文献   
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