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61.
62.
MJ Havenga R Vogels E Braakman N Kroos D Valerio A Hagenbeek HH van Es 《Canadian Metallurgical Quarterly》1998,222(2):319-327
The authors addressed 5 issues bearing on the validity of the construct of depressive personality disorder (DPD): its relationship with the Diagnostic and Statistical Manual of Mental Disorders (3rd ed., rev.; American Psychiatric Association, 1987) mood and personality disorders and normal personality dimensions of negative and positive affectivity, its stability over 30-months, and its impact on the course of Axis I depressive disorders. Two samples were used: 156 outpatients with mood disorders, personality disorders, or both, and 267 of their 1st-degree relatives. The association between DPD and dysthymia was fairly modest, whereas the associations with major depression and the personality disorders were quite low. DPD was moderately correlated with both negative and positive affectivity; however, it contributed unique information beyond that available from the 2 emotional superfactors. Finally, DPD was moderately stable over a 30-month period and was associated with a poorer course of depression. 相似文献
63.
Liquid‐to‐solid ratio control as an advanced process control solution for continuous twin‐screw wet granulation 下载免费PDF全文
Niels Nicolaï Fien De Leersnyder Dana Copot Michiel Stock Clara M. Ionescu Krist V. Gernaey Thomas De Beer 《American Institute of Chemical Engineers》2018,64(7):2500-2514
Assuring compliance of intermediate and final quality attributes in a continuous pharmaceutical manufacturing campaign is of utmost importance. Application of corrective actions might be required in real‐time. This work exemplifies the steps needed to identify a linear pulse transfer function for the dynamic behavior of the granule liquid‐to‐solid ratio (%w/w) at the end of the granulation unit of a commercial ConsiGmaTM‐25 production line. Near‐infrared spectroscopy was used to monitor the granule composition in‐line. The outcome for both the tracking and regulator problem using either conventional or model predictive control was implemented and evaluated. Dynamic setpoints were correctly followed and an RMSE of 0.25%w/w with respect to the setpoint was obtained when inducing artificial disturbances. Important practical challenges were also tackled. Examples are fouling, computational limitations, and the limited flexibility of the automation software. Applying the proposed advanced process control solution offers an answer to upstream material flow rate deviations. © 2018 American Institute of Chemical Engineers AIChE J, 64: 2500–2514, 2018 相似文献
64.
Peter J.T.M. van Puijenbroek Anthonie D. Buijse Michiel H.S. Kraak Piet F.M. Verdonschot 《河流研究与利用》2019,35(1):68-77
Fragmentation is one of the major threats to riverine ecosystems and this is most explicitly expressed by the decline in numbers of migratory fish species. Yet each species has different migration requirements and their natural distribution can include several catchments with multiple dams. Hence, to prioritize candidate rivers for improving accessibility, differences between species and between catchments have to be taken into account. The aim of this study was therefore to analyse the species and river specific effects of river fragmentation on migratory fish on a European scale. The effect of river damming on migratory fish was quantified for all 16 European long‐ and mid‐distance anadromous species and for 33 large European rivers. The historical distribution was compared with the current upstream accessibility of the main river and the current distribution and population status of each species. The observed effects of reduced connectivity were further quantified using the Dendritic Connectivity Index for species and the Fragmentation Index for rivers. Our results showed that only very few rivers are still unaffected by dams in the main stem and that the few remaining viable migratory fish populations in Europe occur in these accessible rivers. Barriers were prioritized for making passable based on the potential accessibility gain and the number of benefitting species, showing that the main stems of the rivers Shannon and Nemunas are the best candidates. It was concluded that evaluating species and river specific effects of fragmentation strongly aids in prioritizing rivers for improving upstream accessibility. 相似文献
65.
Paula C. dos Reis Oliveira Michiel H.S. Kraak Piet F.M. Verdonschot Ralf C.M. Verdonschot 《河流研究与利用》2019,35(7):1023-1033
Up to now, most lowland stream restoration projects were unsuccessful in terms of ecological recovery. Aiming to improve the success of stream restoration projects, a novel approach to restore sandy‐bottom lowland streams degraded by channel incision was launched, consisting of the addition of sand to the stream channel in combination with the introduction of coarse woody debris. Yet it remained unknown whether this novel measure of sand addition is actually effective in terms of biodiversity improvements. The aim of the present study was therefore to evaluate if sand addition can improve hydromorphological stream complexity on the short term leading to an increase in macroinvertebrate biodiversity. To this end, particle transport, water depth, current velocity, dissolved oxygen dynamics, and sediment composition were measured. The response of the macroinvertebrate community composition was determined at different stages during the disturbance and short‐term recovery process. Immediately downstream the sand addition site, transport and sedimentation of the sand were initially intense, until an equilibrium was reached and the physical conditions stabilized. The stream section matured fast as habitat formation took place within a short term. Macroinvertebrate diversity decreased initially but recovered rapidly following stabilization. Moreover, an increase in rheophilic taxa was observed in the newly formed habitats. Thus, although sand addition initially disturbed the stream, a relatively fast physical and biological recovery occurred, leading to improved instream conditions for a diverse macroinvertebrate community, including rheophilic taxa. Therefore, we concluded that sand addition is a promising restoration measure for incised lowland streams. 相似文献
66.
Michiel Gossye Dries Vande Ginste Hendrik Rogier 《Computers & Mathematics with Applications》2019,77(6):1626-1638
In this contribution, we present a Calderón preconditioner for a novel single-source equation to efficiently model electromagnetic scattering problems involving high magnetic contrasts. Through analysis of the spectral properties of the system matrix after discretization, it is shown that this formulation does not break down when high permeabilities are present, which was an unresolved problem of the Calderón preconditioned Poggio–Miller–Chan–Harrington–Wu–Tsai method. The adopted discretization scheme, which involves Rao–Wilton–Glisson and Buffa–Christiansen basis functions, allows for an easy integration in existing commercial Method of Moments software. The efficiency and accuracy of the presented method is corroborated by numerical examples. 相似文献
67.
Piotr Antonik Michiel Hermans Marc Haelterman Serge Massar 《Neural Processing Letters》2018,47(3):1041-1054
Reservoir computing is a bio-inspired computing paradigm for processing time dependent signals. The performance of its analogue implementations matches other digital algorithms on a series of benchmark tasks. Their potential can be further increased by feeding the output signal back into the reservoir, which would allow to apply the algorithm to time series generation. This requires, in principle, implementing a sufficiently fast readout layer for real-time output computation. Here we achieve this with a digital output layer driven by a FPGA chip. We demonstrate the first opto-electronic reservoir computer with output feedback and test it on two examples of time series generation tasks: frequency and random pattern generation. We obtain very good results on the first task, similar to idealised numerical simulations. The performance on the second one, however, suffers from the experimental noise. We illustrate this point with a detailed investigation of the consequences of noise on the performance of a physical reservoir computer with output feedback. Our work thus opens new possible applications for analogue reservoir computing and brings new insights on the impact of noise on the output feedback. 相似文献
68.
Tikhonov regularization is a popular method to approximate solutions of linear discrete ill-posed problems when the observed or measured data is contaminated by noise. Multiparameter Tikhonov regularization may improve the quality of the computed approximate solutions. We propose a new iterative method for large-scale multiparameter Tikhonov regularization with general regularization operators based on a multidirectional subspace expansion. The multidirectional subspace expansion may be combined with subspace truncation to avoid excessive growth of the search space. Furthermore, we introduce a simple and effective parameter selection strategy based on the discrepancy principle and related to perturbation results. 相似文献
69.
Michiel T. Kreutzer Menno G. van der Eijnden Freek Kapteijn Jacob A. Moulijn Johan J. Heiszwolf 《Catalysis Today》2005,105(3-4):667-2
The length of the liquid slugs, that separate the elongated bubbles in Taylor flow, is an important parameter for mass transfer, flow stability and pressure drop in capillary microchannels. In this work, pressure drop measurements are used to determine the length of slug in Taylor flow in downflow monoliths. The method is sensitive if the slugs are relatively short, less than 10 times the channel diameter. The pressure drop measurements are a cheap and fast alternative to tomographic or electric methods. Experiments using different distributors indicate that the slug length varies significantly with changes in the hydrodynamics in the feed section of the monoliths. Slug length correlations that are based on parameters inside the channels can therefore not safely be used for a different setup. As a result, the slug length should be measured in each experimental setup, which makes a inexpensive and robust method to do so very welcome. 相似文献
70.
Remko Soer Niek Hollak Marieke Deijs Lucas H. van der Woude Michiel F. Reneman 《Applied ergonomics》2014