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911.
A preliminary planning methodology is presented. This approach relies upon a strategy identification mechanism, a system dynamics model to simulate the behaviour of the identified strategies and multiobjective programming formulations to evaluate them. An application to regional water resources planning in the Guadiana basin is included to illustrate the methodology. 相似文献
912.
M. Isabel Sarr Ana M. García Víctor M. Rivalta Diego A. Moreno Irene Arroyo 《Building and Environment》2006,41(12):1811-1820
Stone works of art exposed to the environment are liable to be deteriorated by the action of biological agents such as bacteria, fungi, mosses, etc. In ornamental fountains, the microorganisms present in water can contribute to these biodeterioration processes. This paper assesses the biodeterioration experienced by the Lions Fountain at the Alhambra Palace in Granada (Spain). Analyses have been made of the biodeterioration of Lions 4, 5 and 9, the biofouling of the fountain basin, and the water supply system. Conventional and molecular biology techniques have identified microorganisms belonging to various microbial groups (-, β- and γ-Protebacteria, Chlamydiae/Verrucomicrobia and Eukaryota). Additionally, on the mortar in the sculptures the presence of algae and bryophytes has been observed. X-ray diffraction allowed both the detection of neoformation mineral products that can be related with the presence of microorganisms and the corrosion products in the Lions Fountain. A number of recommendations are made regarding the prevention and control of biodeterioration in this important work of art. 相似文献
913.
城市地域扩散已成为当代的一个普遍现象,城市规划师的职责是对自然和城市环境进行保护和限制.在"景观"这一概念中,既有物质的内容--环境设计,也包含了对想象的认知--精神意义的解释和表达.景观文化表达了人类和自然作为一种两元关系,是如何在地域变化过程中互补和相互平衡的. 相似文献
914.
ABSTRACTThrough a literature review, this paper proposes an assessment framework to evaluate environmental open data in urban platforms under the data life cycle approach. For this purpose, a set of quantitative and qualitative indicators has been defined for each of the stages of the data life cycle: acquisition, access, analysis, and application. As confirmation of the capabilities of this approach, we illustrate the results of its application in six data portals along with analyses, comparisons, and conclusions regarding the results. The cases reveal that an interest exists in providing environmental information, but the capability to transform the data information into knowledge relevant for cities is rather low. 相似文献
915.
Rivers, streams and municipal and industrial effluents flowing into the Ferrol Ria (NW Spain) were analyzed for dissolved and particulate trace elements (Cd, Cu, Pb, Zn), particulate major elements (Al, Fe, Si), particulate organic carbon and nitrogen (POC and PON), and total suspended solids. Trace metal clean techniques were applied. Mean annual fluxes of these components were calculated. Dissolved trace metal concentrations in the major freshwater inputs were found to be within typical values for uncontaminated rivers: Cd: 0.020-0.035 nM; Cu: 11.7-19.2 nM; Pb: 0.40-0.71 nM and Zn: 18-54 nM. Two sources of suspended particulate matter (SPM) were observed: (i) a detrital SPM, which becomes more important at high river discharges, with metal concentrations tending to lithogenic values; (ii) an organic- and metal-rich SPM, which becomes dominant at low discharges. Municipal and industrial effluents in the northern shore, despite of constitute a minor freshwater contribution to the bay, were responsible for more than 50% of total inputs of Cu, Cd, Pb, Zn, POC and PON. The fluxes of trace metals obtained for the Ferrol Ria are in the range of other inhabited world semi-enclosed embayments. 相似文献
916.
de Carlan L Price R Chartier JL Kodeli I Siebert B Henninger J Posselt J Gualdrini G Agosteo S Bedogni R Bordy JM Cassette P Ferrari P Gomez Ros JM Grosswendt B Lacoste V Pola A Rollet S Schultz F Simakov SP Tanner R Terrissol M Zankl M 《Radiation protection dosimetry》2008,131(1):15-23
In the frame of the EU Coordination Action CONRAD (coordinated network for radiation dosimetry), WP4 was dedicated to work on computational dosimetry with an action entitled 'Uncertainty assessment in computational dosimetry: an intercomparison of approaches'. Participants attempted one or more of eight problems. This paper presents the results from problems 4-8-dealing with the overall uncertainty budget estimate; a short overview of each problem is presented together with a discussion of the most significant results and conclusions. The scope of the problems discussed here are: the study of a (137)Cs calibration irradiator; the manganese bath technique; the iron sphere experiment using neutron time-of-flight technique; the energy response of a RADFET detector and finally the sensitivity and uncertainty analysis for the recoil-proton telescope discussed in the companion paper. 相似文献
917.
In this article, we study the problem of recovering the unknown solution of a linear ill-posed problem, via iterative regularization methods, from a statistical point of view. The basic purpose of the paper is to develop adaptive model selection techniques for determining the regularization parameters, i.e., the iteration index. We assume observations are taken over a fixed grid and we consider solutions over a sequence of finite-dimensional subspaces. Based on concentration inequalities techniques, we derive non-asymptotic optimal upper bounds for the mean square error of the proposed estimator. 相似文献
918.
O'Dwyer C Lavayen V Fuenzalida D Lozano H Santa Ana MA Benavente E González G Sotomayor Torres CM 《Small (Weinheim an der Bergstrasse, Germany)》2008,4(7):990-1000
Both low-dimensional bar-coded metal oxide layers, which exhibit molecular hinging, and free-standing organic nanostructures can be obtained from unique nanofibers of vanadium oxide (VO(x)). The nanofibers are successfully synthesized by a simple chemical route using an ethanolic solution of vanadium pentoxide xerogel and dodecanethiol resulting in a double bilayered laminar turbostratic structure. The formation of vanadium oxide nanofibers is observed after hydrothermal treatment of the thiol-intercalated xerogel, resulting in typical lengths in the range 2-6 microm and widths of about 50-500 nm. We observe concomitant hinging of the flexible nanofiber lamina at periodic hinge points in the final product on both the nanoscale and molecular level. Bar-coded nanofibers comprise alternating segments of organic-inorganic (thiols-VO(x)) material and are amenable to segmented, localized metal nanoparticle docking. Under certain conditions free-standing bilayered organic nanostructures are realized. 相似文献
919.
Alison C. Dunn Jessica A. Cobb Ana N. Kantzios Sung Jin Lee Malisa Sarntinoranont Roger Tran-Son-Tay W. Gregory Sawyer 《Tribology Letters》2008,30(1):13-19
Soft biomaterials are often used in applications that involve contact and relative motion against biological tissues, as well
as complicated and variable environments. The friction coefficient of these contacts involving living human cells is of key
importance in the analysis and success of these devices. This work measures the contacting friction coefficient between soft
hydrogel biomaterial surfaces against live human corneal epithelial cells using a custom micro-tribometer. The friction coefficients
were of the order of μ = 0.03 for contacts that did not cause gross destruction of the cell layer. Damage to the confluent
cell layer was assessed using a Trypan blue stain with optical microscopy. This damage was quantified statistically using
image-processing software. The damage was also correlated to in situ friction measurements, with the lowest friction values
seen on undamaged cells and higher friction on damaged regions. 相似文献
920.
Gerardo Espinosa-Velázquez Ana Mayela Ramos-de-la-Peña Julio Montanez Juan Carlos Contreras-Esquivel 《Food science and biotechnology》2018,27(2):411-415
Functional food has been highly demanded lately because of its benefits in counteracting diseases. Fucoidan and agave fructan are ingredients that enhance the growth of beneficial bacteria in the gut (prebiotics). This mixture has great potential to develop innovative products but it has never been explored before. Because of fucoidan is more expensive than agave fructan, the innovative proposed mixture is vulnerable to adulteration. This research was aimed to assess the accuracy of Fourier transform infrared spectroscopy with attenuated total reflectance (ATR–FTIR) coupled with chemometrics to identify and predict concentration of both polysaccharides in powder mixtures (0–100%). Absorption bands at 1240–1255 and 836–840 cm?1 were attributed to fucoidan and a strong peak at ~ 936 cm?1 confirmed the fructan presence. Peak areas were best fitted into linear models (\({\text{R}}_{\text{adj}}^{2}\) ≥ 0.92, RMSE ≤ 3.54%). This achievement may be useful to certificate ingredients contained in fucoidan–fructan mixtures, preventing adulteration. 相似文献