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"This paper is addressed to intraregional income inequalities in the Netherlands. Various concepts are used to measure the degree of regional poverty. In addition, dissimilarity between intraregional income distributions is studied. At the provincial level, relatively small and decreasing dissimilarities are observed. However, at lower spatial levels (especially within metropolitan areas) much larger dissimilarities in mean income and income distribution occur. In the Netherlands, urban poverty has become a more intense and widespread phenomenon than rural poverty."  相似文献   
3.
For some years now, the Nederlandse Taalunie (Dutch Language Union) has been active in promoting the development of human language technology (HLT) applications for speakers of Dutch with communicative disabilities. The reason is that HLT products and services may enable them to improve their communication skills and verbal autonomy. We sought to identify a minimum common set of HLT resources that is required to develop tools for a wide range of communication disabilities. In order to reach this goal, we investigated the specific needs of communicatively disabled people and related these needs to the underlying HLT software components. By analysing the availability and quality of these essential HLT resources, we were able to identify which of the crucial elements need further research and development to become usable for developing applications for communicatively disabled speakers of Dutch. The results obtained in the current survey can be used to inform policy institutions on how they can stimulate the development of HLT resources for this target group. In the current survey results were obtained for Dutch, but a similar approach can also be applied to other languages.  相似文献   
4.
Computational Fluid Dynamics combined with a particle tracking technique provides valuable information concerning residence times and contact times in chemical reactors. In drinking water treatment, for example an accurate estimation of the disinfection is important to predict the microbial safety. Ozone contactors are widely used for disinfection, but the complex geometry of the system causes suboptimal hydraulics and requires optimizations of the flow. This results in a lower ozone dosage, which may reduce the formation of unwanted disinfection-by-products and the consumption of energy. To that end disinfection needs to be calculated precisely, accounting for the complex hydraulics. Several calculation methods estimating the disinfection performance of ozone contactors were evaluated using Computational Fluid Dynamics. For an accurate disinfection prediction, the full distribution of ozone exposures (CT values) is needed, only a mean CT value or residence time distribution provides insufficient information for an accurate disinfection prediction. Adjustments to the geometry of the ozone contactor that reduce the short-circuit flows resulted in an increase in disinfection capacity, whereas the mean CT value remained the same. A sensitivity analysis with respect to the kinetics was conducted. The gain in disinfection capacity obtained by optimizing the hydraulics was significant for typical values used in practice.  相似文献   
5.
In the current debate about the future of the Dutch countryside, more and more attention is drawn to the role of landscape heritage. Spatial designers are asked to translate historic identities into spatial forms in order to bridge the gap between past and future. Special cultural heritage policies are developed to stimulate a shift in design practice and to increase awareness of the value of cultural landscapes. Because interpretation of the rural landscape is often rooted in nostalgia, most conservation efforts are directed at old historical landscapes and rural scenes. But what about modern rural landscapes? How do these landscapes relate to the emerging issue of heritage protection and development? To answer this question the historical significance of these landscapes was examined by analyzing their design in the slipstream of post-war reconstruction. Attention was also given to their possible future in a planning and management context that is increasingly influenced by a public and professional demand for landscape conservation and heritage. We argue that these landscapes are at odds with the values and core convictions of the current heritage policies and merit recognition in their own right.  相似文献   
6.
BACKGROUND: Fermentative production of 1‐butanol yields dilute aqueous solutions. Recovery of the butanol from these solutions is most commonly performed by energy‐intensive distillation. This work investigated the liquid‐liquid (L‐L) phase behavior of mixtures of butanol and water to explore the potential of using L‐L phase separation as a recovery possibility for 1‐butanol. The phase behavior is preferably influenced by compounds already present in the fermentation, such as carbohydrates and salts. RESULTS: The L‐L phase equilibria of butanol and water were determined in the presence of glucose, fructose, sucrose, NaCl, LiCl and CaCl2. The aqueous and organic phase split is more pronounced in the presence of salts than in the presence of carbohydrates. Demixing is achieved with about 0.3 kg salt kg?1 aqueous phase containing 40 g of butanol. CONCLUSION: Operation of L‐L based recovery using salts or carbohydrates requires extreme concentrations of those compounds. For feed material containing 40 g kg?1 butanol, the tested carbohydrates do not influence the phase equilibria sufficiently to allow butanol separation. Fermentative butanol concentrations up to 70 g kg?1 are required to create an effective L‐L phase split. The remaining residual aqueous carbohydrate solution might be used as feed for a following fermentation. Copyright © 2011 Society of Chemical Industry  相似文献   
7.
This paper aims to investigate the entrepreneurial migrants' preferences for a location for business activities in developing countries. In the modelling framework six socio-economic and six socio-cultural variables are used in this study to investigate the migrants' propensity to stay at a particular region. The empirical research was carried out in East Nusa Tenggara, Indonesia. It appears that the presence of a supporting informal network is the most critical factor that attracts and keeps the entrepreneurial migrants in a particular region. Socio-cultural variables like experience and education play a less significant role in the migrants' decision to stay in a given region. RID="*" ID="*" Kees Gorter passed away in October 2001.  相似文献   
8.
Determination of the sedimentation–diffusion equilibrium is one of the methods furnishing data on the thermodynamic parameters of polymer solutions. By means of this procedure measurements can be performed over a considerable range of concentrations. The equilibria in the ultracentrifuge have been determined for five polystyrene samples of narrow distribution covering the molecular weight range 2 × 104 to 2 × 106, at concentrations up to 40 wt-% and at temperatures of 30, 45 and 65 °C. The results are expressed in the data for the chemical potential of the solvent, the number-average chemical potential of the polymer and the interaction parameter ξ. The results are compared with those obtained from osmotic pressure, light scattering and critical miscibility measurements. At very low concentrations the molecular weight dependence of the interaction parameter is in agreement with literature values derived from osmotic pressure and light scattering figures. At higher concentrations this molecular-weight dependence decreases sharply but remains noticeable up to 40% concentration.  相似文献   
9.
An industrial view on compact modeling   总被引:1,自引:0,他引:1  
Compact modeling is an area that gets more and more mature. Collaborations and standardization efforts have emerged. In this paper we present some special requirements that are important when constructing physics-based compact models. We will substantiate our statements on two recent examples, an inductor model and a MOSFET model.  相似文献   
10.
This is the report on the Workshop on Flow-Based Network Management, held within the 37th IRTF NMRG meeting, during IETF 93, on 24th July 2015, in Prague, Czech Republic. Following the tradition of the IRTF NMRG, the workshop focused on technologies, developments, and challenges of using flow-level traffic measurements for network management.  相似文献   
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