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41.
42.
Mathematical modelling of drying processes as well as dryers has become an active and challenging area of research internationally. Despite the volume of literature published and continuing to appear on this subject, much remains to be accomplished in view of the intrinsic complexities associated with coupled heat, mass and momentum transfer with or without phase change occurring in porous media which are often deformable as well. Characterization of the solid media is still a major obstacle to modelling of drying. Since industrial drying is increasingly carried out using several modes of heat transfer (e.g. convection coupled wih conduction or microwave or infrared heating modelling of drying or dryers will remain an important research area in the years to come.

We hope that this bibliography will serve as a useful tool for both the novice as well as the experienced researcher in the subject area in locating appropriate literature for a critical evaluation.  相似文献   
43.
This paper describes a tool for assisting lawyers and paralegal teams during document review in eDiscovery. The tool combines a machine learning technology (CategoriX) and advanced multi-touch interface capable of not only addressing the usual cost, time and accuracy issues in document review, but also of facilitating the work of the review teams by capitalizing on the intelligence of the reviewers and enabling collaborative work.  相似文献   
44.
Morphology development during the synthesis at room temperature of an interpenetrating polyurethane/poly(methyl methacrylate) network was investigated by small-angle X-ray scattering in relation with their relative kinetics of formation, determined by Fourier transform infra red spectroscopy. When the time lag between the onset of the two reactions is short, macroscopic phase separation occurs as the polyurethane network is incompletely formed. However, when the time lag increases, the poly(methyl methacrylate) forms into a more continuous network which limits the growth of phase separation to a close environment.  相似文献   
45.
This paper presents a validation of the thermo-radiative model SOLENE and its application for analysing the street canyon energy balance. The validation data were selected from the temperature and radiation measurements obtained during the JAPEX campaign, previously described by Idczak et al. [16]: a set of four lines of steel containers buildings composing three parallel street canyons at an approximate 1:5 scale. Reference weather data and micrometeorological conditions within the canyon were measured. Numerical simulations were carried out using the meteorological measurements as model inputs. The simulated surface temperatures and radiation fluxes are compared with the measurements for a full week period, with a focus on a day with clear sky conditions. The street canyon energy balance analysis demonstrates that the most energetic surface was the street ground due to its thick surface layer of tar-coated gravels while the walls had a low heat capacity. The thermal radiation balance was negative for all canyon surfaces. The sensible heat was transferred mainly from the canyon surfaces to the ambient air, but also from the air to the ground in the morning. The effective albedo of the canyon had a diurnal value of 0.20–0.25, but dropped to 0.10 in the afternoon when the ground strongly transformed the direct and reflected solar radiation into sensible heat. This narrow street configuration enhanced solar radiation absorption and longwave radiation trapping.  相似文献   
46.
Polymem is developing in the past few years a new membrane bioreactor concept using external module membranes. The membranes are hollow fibers. They are housed in carters and work in outside/in filtration mode. Permanent air scouring is provided at the bottom of the module to control the accumulation of sludge on the membrane surface. In other words, the membrane carters look like bubble columns with hollow fiber membranes inside.The main advantages of this concept are the easy maintenance of the external modules; the total independence of the bioreactor from the membrane filtration part, which facilitates plant retrofitting and upgrading; the high membrane compacity (up to 500 m²/m3), and better efficiency of membrane air scouring thanks to a dedicated coarse bubbles aeration system inside the module vessel.The first part of this paper deals with the quantification of the specific aeration demand of the system. Aeration demand was compared to conventional MBR systems. The study shows that with this optimised geometry of module concept, the aeration flow rate is lowered compared with conventional processes.In the second part of this paper, an optimisation of the aeration demand was carried out by sequencing the cycle of aeration by incorporating a syncope in the aeration. Ratios of the time-on and time-off from 1/2 to 1/5 were tested for various instantaneous aeration flow rates. Impacts on both short term fouling and long term fouling were evaluated and quantified in terms of permeability decrease. The advantages of the location of the membrane in an external cylindrical carter have been demonstrated in terms of operating cost savings with a reduction of specific aeration demand for membranes scouring at 100 to 250 Nl/h m², which is half the classical consumption of the submerged MBR today.  相似文献   
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48.
The telecommunication systems require introduction of high performance devices especially for microwave applications. The emergence of molecular beam epitaxy as a growth technique allows the fabrication of heterostructure-based performing devices. Thus, this communication will focus on the reliability of technologies used for the development of field effect transistor using heterostructures and called HEMT (high electron mobility transistor).  相似文献   
49.
Erratum     
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50.
We present a theoretical and experimental study of laser diodes under strong sinusoidal current modulation. Situations where the diodes are biased above threshold are considered. The first part describes different behaviors occurring under strong modulation. The GaAs lasers are compared to the InGaAsP lasers. The major result of numerical calculations shows that the existence of anomalous behaviors (period doubling, chaos,...) can be predicted from the weak-signal response of the laser. In a second part, we report on the expérimentais results obtained with an InGaAsP laser at 1.3 µ.m and their comparison with the theoretical calculations from a rate equation model. This kind of laser does not exhibit any anomalous behaviour under strong modulation, but distorsion effects occur. The calculated spectra of the laser intensity are in excellent agreement with measurements, which validates both the use of the rate equation model and the choice of the laser-parameters. In contrast, the spectral analysis at the optical frequency shows that the optical phase-equation previously used by many authors is uncomplete and that longitudinal and/or transversal variations of the α-factor have to be taken into account.  相似文献   
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