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1.
Lean practices are known to increase operational performance. Previous research has identified critical success factors for implementing lean practices. This research aims to examine the extent to which success factors are critical for various degrees of lean practice implementation. Using multiple-respondent self-assessments from 33 Dutch manufacturing small and medium-sized enterprises (SMEs), we conducted a Necessary Condition Analysis. Our findings indicated that the criticality of success factors is progression dependent. In the initial stages of the lean journey, SMEs could improve their lean practices in a bottom-up manner through local factors such as a learning focus, improvement training and support congruence. When lean practices are more advanced, some company-wide factors must be present: top management support, a shared improvement vision and a supplier link. Our findings question the universality of success factors such as strategic involvement and indicate the need for a more dynamic model of lean implementation. 相似文献
2.
Ronen Gottesman Angang Song Igal Levine Maximilian Krause A. T. M. Nazmul Islam Daniel Abou‐Ras Thomas Dittrich Roel van de Krol Abdelkrim Chemseddine 《Advanced functional materials》2020,30(21)
A new method for enhancing the charge separation and photo‐electrochemical stability of CuBi2O4 photoelectrodes by sequentially depositing Bi2O3 and CuO layers on fluorine‐doped tin oxide substrates with pulsed laser deposition (PLD), followed by rapid thermal processing (RTP), resulting in phase‐pure, highly crystalline films after 10 min at 650 °C, is reported. Conventional furnace annealing of similar films for 72 h at 500 °C do not result in phase‐pure CuBi2O4. The combined PLD and RTP approach allow excellent control of the Bi:Cu stoichiometry and results in photoelectrodes with superior electronic properties compared to photoelectrodes fabricated through spray pyrolysis. The low photocurrents of the CuBi2O4 photocathodes fabricated through PLD/RTP in this study are primarily attributed to their low specific surface area, lack of CuO impurities, and limited, slow charge transport in the undoped films. Bare (without protection layers) CuBi2O4 photoelectrodes made with PLD/RTP shows a photocurrent decrease of only 26% after 5 h, which represents the highest stability reported to date for this material. The PLD/RTP fabrication approach offers new possibilities of fabricating complex metal oxides photoelectrodes with a high degree of crystallinity and good electronic properties at higher temperatures than the thermal stability of glass‐based transparent conductive substrates would allow. 相似文献
3.
Margreet Heida Ghyslaine C.B. Schopen Marinus F.W. te Pas Birgit Gredler-Grandl Roel F. Veerkamp 《Journal of dairy science》2021,104(8):8966-8982
Current breeding tools aiming to improve feed efficiency use definitions based on total dry matter intake (DMI); for example, residual feed intake or feed saved. This research aimed to define alternative traits using existing data that differentiate between feed intake capacity and roughage or concentrate intake, and to investigate the phenotypic and genetic relationships among these traits. The data set contained 39,017 weekly milk yield, live weight, and DMI records of 3,164 cows. The 4 defined traits were as follows: (1) Feed intake capacity (FIC), defined as the difference between how much a cow ate and how much she was expected to eat based on diet satiety value and status of the cow (parity and lactation stage); (2) feed saved (FS), defined as the difference between the measured and the predicted DMI, based on the regression of DMI on milk components within experiment; (3) residual roughage intake (RRI), defined as the difference between the measured and the predicted roughage intake, based on the regression of roughage intake on milk components and concentrate intake within experiment; and (4) residual concentrate intake (RCI), defined as the difference between the measured and the predicted concentrate intake, based on the regression of concentrate intake on milk components and roughage intake within experiment. The phenotypic correlations were ?0.72 between FIC and FS, ?0.84 between FS and RRI, and ?0.53 between FS and RCI. Heritability of FIC, FS, RRI, and RCI were estimated to be 0.21, 0.12, 0.15, and 0.03, respectively. The genetic correlations were ?0.81 between FS and FIC, ?0.96 between FS and RRI, and ?0.25 between FS and RCI. Concentrate intake and RCI had low heritability. Genetic correlation between DMI and FIC was 0.98. Although the defined traits had moderate phenotypic correlations, the genetic correlations between DMI, FS, FIC, and RRI were above 0.79 (in absolute terms), suggesting that these traits are genetically similar. Therefore, selecting for FIC is expected to simply increase DMI and RRI, and there seems to be little advantage in separating concentrate and roughage intake in the genetic evaluation, because measured concentrate intake was determined by the feeding system in our data and not by the genetics of the cow. 相似文献
4.
5.
Skodol Andrew E.; Bender Donna S.; Oldham John M.; Clark Lee Anna; Morey Leslie C.; Verheul Roel; Krueger Robert F.; Siever Larry J. 《Canadian Metallurgical Quarterly》2011,2(1):23
The four-part assessment of personality psychopathology proposed for DSM-5 focuses attention on identifying personality psychopathology with increasing degrees of specificity, based on a clinician's available time, information, and expertise. In Part I of this two-part article, we described the components of the new model and presented brief rationales for them. In Part II, we illustrate the clinical application of the model with vignettes of patients with varying degrees of personality psychopathology, selected from the DSM–IV–TR Casebook, to show how assessments might be conducted and diagnoses reached. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
6.
7.
New competitive results for the stochastic resource-constrained project scheduling problem: exploring the benefits of pre-processing 总被引:1,自引:0,他引:1
We study the resource-constrained project scheduling problem with stochastic activity durations. We introduce a new class
of scheduling policies for solving this problem, which make a number of a-priori sequencing decisions in a pre-processing
phase while the remaining decisions are made dynamically during project execution. The pre-processing decisions entail the
addition of extra precedence constraints to the scheduling instance, hereby resolving some potential resource conflicts. We
obtain new competitive results for expected-makespan minimization on representative datasets, which are significantly better
than those obtained by the existing algorithms when the variability in the activity durations is medium to high. 相似文献
8.
Aykut Avci Jan De CockPeter Lambert Roel BeernaertJelle De Smet Lawrence BogaertYouri Meuret Hugo ThienpontHerbert De Smet 《Journal of Visual Communication and Image Representation》2012,23(2):287-292
An efficient disparity estimation algorithm for multi-view video sequences, recorded by a two-dimensional camera array in which the cameras are spaced equidistantly, is presented. Because of the strong geometrical relationship among views, the disparity vectors of a certain view can for most blocks be derived from the disparity vectors of other views. A frame constructed using that idea is called a D frame in this work. Three new prediction schemes which contain D frames are proposed for encoding 5 × 3 multi-view video sequences. The schemes are applied to several multi-view image sequences taken from a camera-array and they are compared in terms of quality, bit-rate and complexity. The experimental results show that the proposed prediction schemes significantly decrease the complexity of the encoder at a very low cost of quality and/or bit-rate. 相似文献
9.
Roel Vossen 《家电科技》2010,(7):64-66
<正>一、内衬制造技术及其树脂材料对于冰箱内衬层的制造,业界内普遍认为挤出/热成型工艺是生产效率最高和加工适应性最好的制造技术。与注塑模塑和吹塑模塑工艺相比,热成型工艺是一种低温、低压工艺过程,所需的模具材料也比较便宜、重量也较轻,因此可以以较低的成本实现快速工装。 相似文献
10.
New process for the production of methanol and ammonia. The gas/solids/solids thrickle flow reactor – a new kind of reactor for chemical equilibrium processes . A new process for the production of ammonia or methanol has been developed in the high pressure laboratory of Twente Technical University. The reactants can be made to react completely in a single reactor pass, thus avoiding expensive recirculation. Complete reaction without recirculation is accomplished by a combination of two reversible processes: a chemical reaction and a selective adsorption of the reaction product on a solid in constant flow. On introduction of an inert-gas free stoichiometric mixture of reactants into the reactor, the exhaust gas outlet can be closed. If there is an excess of one of the reactants or of inert gas, it can leave from the top of the reactor. Such a process has been accomplished in a new gas/solids/solids trickle flow reactor in which a granulated adsorbent ?rains”? through a fixed bed of catalyst. The present article describes the use of this kind of reactor for methanol synthesis. Considerable savings in production costs are expected relative to the modern Lurgi low pressure process. A pilot plant is to be built to characterize and evaluate the new process. Royal Dutch Shell has registered a patent application. 相似文献