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31.
这是一个在商业公园、港口和机场之间开发的项目,要求不能违背大加那利群岛的地理特质。我们的目标是提高这些本地条件,注入明确的城市规划和景观规划方案。我们计划建立3个超级区域网络:东西向的地景河床 相似文献
32.
Correlating the effects of ash elements and their association in the fuel matrix with the ash release during pulverized fuel combustion 总被引:1,自引:0,他引:1
Kalpit V. Shah Mariusz K. Cieplik Willem L. van de Kamp 《Fuel Processing Technology》2010,91(5):531-14
During pulverized fuel combustion, inorganic elements such as alkalis, sulfur, chlorine, calcium and magnesium, as well as a range of minor elements are partly released into the gas phase. These gas-borne species can nucleate, coagulate and condense to form either aerosol particles or sticky layers on ash particles, leading to ash deposition and corrosion problems in power utilities. Furthermore, the fine aerosols can lead to harmful gaseous and particulate emissions. It is well documented that the mode of occurrence and the chemical speciation of ash forming elements in the coal/biomass structure are important for the release behavior of mineral components. In the presented work, this is investigated by performing quantitative elemental investigations of ash releases for two different coals (a Polish and a UK coal) and six diverse biomass fuels (Wood bark, Wood chips, Waste wood, Olive residue, Saw dust and Straw). The tests are performed within the Lab-scale Combustion Simulator (LCS) of the Energy Research Centre of the Netherlands (ECN). The operating conditions applied were that of a typical pulverized fuel (PF) fired boiler i.e. atmospheric pressure, high temperatures of 1400-1650 °C, and high heating rate of 105 K/s. Gas phase elemental release of alkalis, sulfur, chlorine, calcium and magnesium has been quantified at relevant high carbon conversion levels. With the performed set of experiments several of the past observations from the literature are reconfirmed. In addition to this, based on the extensive data pool at hand, a simple but reliable (R2 > 0.95) set of linear correlations have been proposed to predict the elemental release of potassium, sodium, chlorine and sulfur. It is also concluded that such linear expressions can be particularly effective for the prediction of elemental release from the fuels of similar characteristics, such as woody biomass. 相似文献
33.
Marike Polak Willem J. Heiser Mark de Rooij 《Computational statistics & data analysis》2009,53(8):3117-3128
It has been argued that principal component analysis (PCA) is not appropriate for analyzing data conforming to single-peaked response models, also referred to as unfolding models. An overview of these findings is given, which relates them to the distinction between two types of unfolding models; namely, models that are either a quadratic function of the person-to-item distances or an exponential function of these distances. This distinction is easy to recognize empirically because the inter-item correlation matrix for the two types of data typically shows different patterns. Furthermore, for both types of unfolding models, correspondence analysis (CA), which is a rival method for dimensionality reduction, outperforms PCA in terms of representation of both person and item locations, especially for the exponential unfolding model. Finally, it is shown that undoubled CA outperforms doubled CA for both types of unfolding models. It is argued that performing CA on the raw data matrix is an unconventional, but meaningful approach to scaling items and persons on an underlying unfolding scale. A real data example on personality assessment is given, which shows that for this type of data (undoubled) CA is to be preferred over PCA. 相似文献
34.
Integrated microfluidic system enabling (bio)chemical reactions with on-line MALDI-TOF mass spectrometry 总被引:2,自引:0,他引:2
Brivio M Fokkens RH Verboom W Reinhoudt DN Tas NR Goedbloed M van den Berg A 《Analytical chemistry》2002,74(16):3972-3976
A continuous flow micro total analysis system (micro-TAS) consisting of an on-chip microfluidic device connected to a matrix assisted laser desorption ionization [MALDI] time-of-flight [TOF] mass spectrometer (MS) as an analytical screening system is presented. Reaction microchannels and inlet/outlet reservoirs were fabricated by powderblasting on glass wafers that were then bonded to silicon substrates. The novel lab-on-a-chip was realized by integrating the microdevice with a MALDI-TOFMS standard sample plate used as carrier to get the microfluidic device in the MALDI instrument. A novel pressure-driven pumping mechanism using the vacuum of the instrument as a driving force induces flow in the reaction microchannel in a self-activating way. Organic syntheses as well as biochemical reactions are carried out entirely inside the MALDI-MS ionization vacuum chamber and analyzed on-line by MALDI-TOFMS in real time. The effectiveness of the micro-TAS system has been successfully demonstrated with several examples of (bio)chemical reactions. 相似文献
35.
Back JW Notenboom V de Koning LJ Muijsers AO Sixma TK de Koster CG de Jong L 《Analytical chemistry》2002,74(17):4417-4422
A new method is presented to screen proteolytic mass maps of cross-linked protein complexes for the presence of cross-linked peptides and for the verification of proposed structures. On the basis of the incorporation of 18O from isotopically enriched water into the C-termini of proteolytic peptides, cross-linked peptides are readily distinguished in mass spectra by a characteristic 8 amu shift. This is due to the incorporation of two 18O atoms in each C-terminus, so that normal and surface-labeled peptides shift 4 amu and cross-linked peptides containing two C-termini will shift 8 amu compared with their unlabeled counterparts. The method is fast, sensitive, and reliable and can be combined with any available cross-linking reagent and a wide range of proteolytic agents. As proof of principle, we successfully applied the method to a complex of two DNA repair proteins (Rad18-Rad6) and identified the interaction domain. 相似文献
36.
Hilderick A. van der Meiden Author Vitae Willem F. Bronsvoort Author Vitae 《Computer aided design》2006,38(4):275-283
Geometric constraints are at the heart of parametric and feature-based CAD systems. Changing values of geometric constraint parameters is one of the most common operations in such systems. However, because allowable parameter values are not known to the user beforehand, this is often a trial-and-error process. We present an approach for automatically determining the allowable range for parameters of geometric constraints. Considered are systems of distance and angle constraints on points in 3D that can be decomposed into triangular and tetrahedral subproblems, by which most practical situations in parametric and feature-based CAD systems can be represented. Our method uses the decomposition to find critical parameter values for which subproblems degenerate. By solving one problem instance for each interval between two subsequent critical values, the exact parameter range is determined for which a solution exists. 相似文献
37.
Soil moisture retrieval using thermal inertia, determined with visible and thermal spaceborne data, validated for European forests 总被引:2,自引:0,他引:2
Willem W. Verstraeten Frank Veroustraete Ief Grootaers 《Remote sensing of environment》2006,101(3):299-314
Variations in soil moisture strongly affect surface energy balances, regional runoff, land erosion and vegetation productivity (potential crop yield). Hence, the detection of soil moisture content (SMC) is very valuable in the social, economic, humanitarian (food security) and environmental segments of society. A method to estimate SMC from optical and thermal spectral information of METEOSAT imagery based on thermal inertia (TI) is presented. Minimum and maximum TI values from time series are combined in the Soil Moisture Saturation Index (SMSI). To convert surface to soil profile values, a Markov type filter is used, based on a simple two layer water balance equation (the surface layer and the reservoir below) and an autocorrelation function. Ten-daily SMC values are compared with up-scaled (using AVHRR/NDVI) observations on 10 EUROFLUX sites in Europe for the 1997 growing season (March-October). Moreover, the thermal inertia approach is compared for 1997, with ERS Scatterometer data for eight EUROFLUX sites. METEOSAT pixels are up-scaled to accommodate the ERS Scatterometer spatial resolution. The regression coefficients (slope, intercept and R2) of the thermal inertia approach versus the up-scaled soil moisture observations from EUROFLUX sites vary between 0.811-1.148, − 0.0029-0.66 and 0.544-0.877, respectively, with a RRMSE range of 3.9% to 35.7%. The regression coefficients of the comparison of ERS Scatterometer derived Soil Water Index (SWI) versus the up-scaled Soil Moisture Saturation Index for the pooled case (binning the eight EUROFLUX sites) are 0.587, 0.105 and 0.441, respectively, with a RRMSE of 38%. A simple error propagation model applied for the thermal inertia approach reveals that the absolute and relative errors of the obtained soil moisture content is at least 0.010 m3 m− 3 or 2.0% with a SMC of 0.203 m3 m− 3. Recommendations are made to test and implement the TI methodology using NOAA/AVHRR imagery. 相似文献
38.
Klaus Havelund Willem Visser 《International Journal on Software Tools for Technology Transfer (STTT)》2002,4(1):8-20
This paper introduces a special section of the STTT journal containing a selection of papers that were presented at the 7th
international SPIN workshop, Stanford, 30 August – 1 September 2000. The workshop was named SPIN Model Checking and Software
Verification, with an emphasis on model checking of programs. The paper outlines the motivation for stressing software verification,
rather than only design and model verification, by presenting the work done in the Automated Software Engineering group at
NASA Ames Research Center within the last 5 years. This includes work in software model checking, testing like technologies
and static analysis.
Published online: 2 October 2002 相似文献
39.
40.
de Jong Peter F.; Koomen Willem; Mellenbergh Gideon J. 《Canadian Metallurgical Quarterly》1988,55(5):718
Investigated whether B. Weiner's (1979) model of causal attributions applies to perceptions of the causes for success and failure. Instead of the usual similarity judgments, preference judgments were used to reveal the dimensions underlying these perceptions. Female subjects, randomly assigned to a success or failure condition, made preference judgments with regard to 12 causes for success or failure. Multidimensional scaling analysis uncovered internality, stability, and excusability dimensions, thus supporting Weiner's model at least partly. In addition, differences in the relative emphasis given to the dimensions were found between the success and failure conditions: Following success, the internality dimension was the most salient, whereas after failure the stability and excusability dimensions were the most important. Furthermore, after success subjects preferred more internal causes and more causes that seem inappropriate as an excuse. After failure, subjects chose more external and more excusable causes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献