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131.
M. Djaeni P. Bartels J. Sanders G. van Straten A. J. B. van Boxtel 《Drying Technology》2007,25(6):1053-1067
This work discusses the potential of three multistage zeolite drying systems (counter-, co-, and cross-current) with a varying number of stages. The evaluation showed that for 2-4 stages with heat recovery the efficiency of the systems ranges between 80 and 90%. Additionally, by introducing a compressor, the latent heat in the exhaust air from the regenerator is recovered and used to heat the inlet air for an additional drying stage. As a result, for the counter-current drying system and compressor pressure 1.5-2 bar, a maximum energy efficiency of 120% is achieved, which results in halving the energy consumption compared to conventional drying systems. 相似文献
132.
We describe a formal language/notation for DNA molecules that may contain nicks and gaps. The elements of the language, DNA
expressions, denote formal DNA molecules. Different DNA expressions may denote the same formal DNA molecule. We analyse the
shortest DNA expressions denoting a given formal DNA molecule. We determine lower bounds on their lengths and explain how
we construct these minimal DNA expressions. 相似文献
133.
J H J Hulskotte H A C Denier van der Gon A J H Visschedijk M Schaap 《Water science and technology》2007,56(1):223-231
In this article we show that brake wear from road traffic vehicles is an important source of atmospheric (particulate) copper concentrations in Europe. Consequently, brake wear also contributes significantly to deposition fluxes of copper to surface waters. We estimated the copper emission due to brake wear to be 2.4 kiloton per year. For comparison, the official database for Europe (without brake wear) totals 2.6 kiloton per year. In Western Europe the brake wear emissions dominate the total emission of copper. Using the spatially resolved emission data, copper distributions over Europe were calculated with the LOTOS-EUROS model. Without brake wear the model underestimates observed copper concentrations by a factor of 3, which is in accordance with other studies. Including the brake wear emissions largely removes the bias. We find that 75% of the atmospheric copper input in the North Sea may be due to brake wear. We estimate that about 25% of the total copper input in the Dutch part of the North Sea stems from brake wear. Although the estimated brake wear copper emission is associated with a large uncertainty, it significantly improves our understanding of the copper cycle in the environment. 相似文献
134.
Use of modelling for optimization and upgrade of a tropical wastewater treatment plant in a developing country. 总被引:1,自引:0,他引:1
D Brdjanovic M Mithaiwala M S Moussa G Amy M C M van Loosdrecht 《Water science and technology》2007,56(7):21-31
This paper presents results of a novel application of coupling the Activated Sludge Model No. 3 (ASM3) and the Anaerobic Digestion Model No.1 (ADM1) to assess a tropical wastewater treatment plant in a developing country (Surat, India). In general, the coupled model was very capable of predicting current plant operation. The model proved to be a useful tool in investigating various scenarios for optimising treatment performance under present conditions and examination of upgrade options to meet stricter and upcoming effluent discharge criteria regarding N removal. It appears that use of plant-wide modelling of wastewater treatment plants is a promising approach towards addressing often complex interactions within the plant itself. It can also create an enabling environment for the implementations of the novel side processes for treatment of nutrient-rich, side-streams (reject water) from sludge treatment. 相似文献
135.
Filip Sroubek Gabriel Cristóbal Jan Flusser 《IEEE transactions on image processing》2007,16(9):2322-2332
This paper presents a new approach to the blind deconvolution and superresolution problem of multiple degraded low-resolution frames of the original scene. We do not assume any prior information about the shape of degradation blurs. The proposed approach consists of building a regularized energy function and minimizing it with respect to the original image and blurs, where regularization is carried out in both the image and blur domains. The image regularization based on variational principles maintains stable performance under severe noise corruption. The blur regularization guarantees consistency of the solution by exploiting differences among the acquired low-resolution images. Several experiments on synthetic and real data illustrate the robustness and utilization of the proposed technique in real applications. 相似文献
136.
Carballo V.M.B. Chefdeville M. Fransen M. van der Graaf H. Melai J. Salm C. Schmitz J. Timmermans J. 《Electron Device Letters, IEEE》2008,29(6):585-587
An unpackaged microchip is used as the sensing element in a miniaturized gaseous proportional chamber. This letter reports on the fabrication and performance of a complete radiation imaging detector based on this principle. Our fabrication schemes are based on wafer-scale and chip-scale postprocessing. Compared to hybrid-assembled gaseous detectors, our microsystem shows superior alignment precision and energy resolution, and offers the capability to unambiguously reconstruct 3D radiation tracks on the spot. 相似文献
137.
138.
Danil Van Nieuwenhove Ward van der Tempel Riemer Grootjans Johan Stiens Maarten Kuijk 《IEEE sensors journal》2007,7(3):317-318
A current assisted photonic demodulator for use as a pixel in a 3-D time-of-flight imager shows nearly 100% static demodulator contrast and is operable beyond 30 MHz. An integrated tunable sensitivity control is also presented for increasing the distance measurement range and avoiding unwanted saturation during integration periods. This is achieved by application of a voltage on a dedicated drain tap showing a quenching of sensor sensitivity to below 1% 相似文献
139.
A product line architecture is a single specification capturing the overall architecture of a series of closely related products. Its structure consists of a set of mandatory elements and a set of variation points. Whereas mandatory elements are part of the architecture of every product in the product line architecture, variation points precisely define the dimensions along which the architectures of individual products differ from each other.The increased use of product line architectures in today's software development projects poses several challenges for existing testing techniques. In this paper we discuss those challenges and discuss what we believe are opportunities for addressing them. 相似文献
140.
The authors used visual search tasks in which components of the classic flanker task (B. A. Eriksen & C. W. Eriksen, 1974) were introduced. In several experiments the authors obtained evidence of parallel search for a target among distractor elements. Therefore, 2-stage models of visual search predict no effect of the identity of those distractors. However, clear compatibility effects of the distractors were obtained: Responses were faster when the distractors were compatible with the response than when they were incompatible. These results show that even in parallel search tasks identity information is extracted from the distractors. In addition, alternative interpretations of the results in terms of the occasional identification of a distractor before or after the target was identified could be ruled out. The results showed that flat search slopes obtained in visual search experiments provide no benchmark for preattentive processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献