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101.
This study evaluates the effect of pre-existing relational governance mechanisms on environmental collaboration. Specifically, our study distinguishes between structural and process dimensions of relational governance mechanisms so as to facilitate a more nuanced investigation into the inherent complementarities and performance implications. Using data collected from 145 US firms and a combination of methodologies – three-stage least squares and structural equation modelling, a number of direct, complementary and mediation effects are hypothesised and tested. The three-stage least squares methodology was adopted to overcome endogeneity and simultaneity issues inherent in the hypotheses covering complementarity. Contrary to conventional wisdom, structural and process governance mechanisms were not found to act as complements for environmental collaboration. Instead, the effect of structural mechanisms was found to be completely mediated by the process mechanisms. Thus, process mechanisms of relational governance were found to be much more important in promoting advanced practices such as environmental collaboration. Our results also document the significant mediating role of environmental collaboration. Implications for future research and practice are offered. 相似文献
102.
Antony Stathopoulos & Loukas Dimitriou Theodore Tsekeris 《Computer-Aided Civil and Infrastructure Engineering》2008,23(7):521-535
Abstract: This article addresses the problem of the accuracy of short-term traffic flow forecasting in the complex case of urban signalized arterial networks. A new, artificial intelligence (AI)-based approach is suggested for improving the accuracy of traffic predictions through suitably combining the forecasts derived from a set of individual predictors. This approach employs a fuzzy rule-based system (FRBS), which is augmented with an appropriate metaheuristic (direct search) technique to automate the tuning of the system parameters within an online adaptive rolling horizon framework. The proposed hybrid FRBS is used to nonlinearly combine traffic flow forecasts resulting from an online adaptive Kalman filter (KF) and an artificial neural network (ANN) model. The empirical results obtained from the model implementation into a real-world urban signalized arterial demonstrate the ability of the proposed approach to considerably overperform the given individual traffic predictors . 相似文献
103.
Novel bis(methylimidazolium)alkane bolaamphiphiles as templates for supermicroporous and mesoporous silicas 总被引:1,自引:0,他引:1
Alexander K.L. YuenFalk Heinroth Antony J. WardAnthony F. Masters Thomas Maschmeyer 《Microporous and mesoporous materials》2012,148(1):62-72
A series of bis-cationic bolaamphiphiles were synthesized containing N-methylimidazolium head-groups, separated by alkyl chains of 12, 16 and 24 methylene units. Their critical micelle concentrations were determined with subsequent flooding experiments revealing the tendency for the formation of hexagonal mesophases at high surfactant concentrations. The surfactants were employed as templates for silica formation, at ca. four times their critical micelle concentrations, permitting super-microporous and nanoparticulate mesoporous silicas to be prepared. Silica surface areas ranged from 500 to 1000 m2 g−1, and pore diameters (DTEM) from 10 to 22 Å. Analysis of the materials by small angle X-ray diffraction indicated that, in the case of the template possessing 24 methylene units, the silica obtained exhibited a 2D hexagonal pore arrangement. 相似文献
104.
Livingstone Andrew G.; Spears Russell; Manstead Antony S. R.; Bruder Martin; Shepherd Lee 《Canadian Metallurgical Quarterly》2011,11(4):754
Building on intergroup emotion research, we test the idea that intergroup emotion influences self-categorization. We report two studies using minimal (Study 1) and natural (Study 2) groups in which we measured participants' emotional reactions to a group-relevant event before manipulating the emotional reactions of other ingroup members and outgroup members (anger vs. happiness in Study 1; anger vs. indifference in Study 2). Results supported the hypotheses that (a) the fit between participants' own emotional reactions and the reactions of ingroup members would influence self-categorization, and (b) the specific content of emotional reactions would shape participants' willingness to engage in collective action. This willingness was greater when emotional reactions were not only shared with other group members, but were of anger (consistent with group-based action) rather than happiness or indifference (inconsistent with group-based action). Implications for the relationship between emotion and social identities are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
105.
Reports an error in "Progrès récents dans le traitement des troubles anxieux" by Martin M. Antony (Canadian Psychology/Psychologie canadienne, 2011[Feb], Vol 52[1], 10-19). In the CPA President’s Address article that appeared in the February issue of Canadian Psychology, “Recent advances in the treatment of anxiety disorders” by Martin M. Antony (Canadian Psychology, Vol. 52, No. 1, pp. 10–19), the heading for the article incorrectly printed as “Honourary President’s Address—2010.” It should have read “President’s Address—2010.” The publisher apologizes for this unfortunate production error. The online version has been corrected. (The following abstract of the original article appeared in record 2011-04299-014.) Over the past several decades, evidence-based treatments have emerged for each major anxiety disorder. These include primarily behavioural, cognitive, and pharmacological approaches. In addition, researchers continue to develop new ways of treating anxiety disorders and to improve on existing treatments. This article discusses several new and emerging treatments for anxiety disorders, including attentional training, virtual reality-based treatments, mindfulness and acceptance-based strategies, enhancement of exposure using d-cycloserine, and the application of motivational interviewing strategies in anxiety disorders. For each of these treatments, the current status and directions for future research are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
106.
Dunsmore CJ Malone KJ Bailey KR Wear MA Florance H Shirran S Barran PE Page AP Walkinshaw MD Turner NJ 《Chembiochem : a European journal of chemical biology》2011,12(5):802-810
Cyclophilin A (CypA) is a member of the immunophilin family of proteins and receptor for the immunosuppressant drug cyclosporin A (CsA). Here we describe the design and synthesis of a new class of small-molecule inhibitors for CypA that are based upon a dimedone template. Electrospray mass spectrometry is utilised as an initial screen to quantify the protein affinity of the ligands. Active inhibitors and fluorescently labelled derivatives are then used as chemical probes for investigating the biological role of cyclophilins in the nematode Caenorhabditis elegans. 相似文献
107.
Simultaneous Optimisation of Multiple Quality Characteristics in Manufacturing Processes Using Taguchi's Quality Loss Function 总被引:1,自引:1,他引:0
J. Antony 《The International Journal of Advanced Manufacturing Technology》2001,17(2):134-138
Taguchi methods have proved to be successful over the last fifteen years or so for the improvement of product quality and
process performance. Most Taguchi experiments are concerned with the optimisation of a single quality characteristic. Optimisation
of multiple quality characteristics in manufacturing processes is not common and has received very little attention among
the Taguchi practitioners. Many engineers using Taguchi methods have employed pure engineering judgement when dealing with
multiple quality characteristics in manufacturing process optimisation. This approach is very subjective and therefore always
brings an element of uncertainty to the decision-making process. This paper presents an alternative approach for tackling
such optimisation problems using Taguchi’s quality loss function analysis. The paper also presents a case study to illustrate
the potential of the proposed methodology. 相似文献
108.
V. D. Tathavadkar A. Jha M. P. Antony 《Metallurgical and Materials Transactions B》2001,32(4):593-602
Soda-ash roasting of the chromite mineral is commonly used worldwide for the production of watersoluble sodium chromate. The
formation of sodium chromate during the soda-ash roasting reaction depends on the oxygen partial pressure and availability
of oxygen at the reaction front. The effects of temperature, oxygen partial pressure, charge composition, and their roles
on the overall roasting reaction were studied in order to analyze the reaction mechanism. The influence of process parameters
such as the addition of alkali and process residue as the filler material on the overall reaction rate is discussed. The rate-determining
steps for the soda-ash roasting reaction are analyzed. The importance of the binary Na2CO3-Na2CrO4 liquid phase during the reaction in determining its speed is also examined. It is shown that the experimental results for
the roasting reaction can be best described by the Ginstling and Brounshtein (GB) equation for diffusion-controlled kinetics.
From the measured kinetics data, the apparent activation energy for the roasting reaction was calculated to be between 180
and 190 kJ · mol−1 in the temperature range from 1023 to 1210 K and between 35 and 40 kJ · mol−1 above 1210 K. 相似文献
109.
Influence of thermal aging on sulfate-reducing bacteria (SRB)-influenced corrosion behaviour of 2205 duplex stainless steel 总被引:1,自引:0,他引:1
Microbiologically-influenced corrosion behaviour of thermally aged 2205 duplex stainless steel in comparison to the as-received material was studied by exposing the coupons for 40 days in chloride medium containing sulfate-reducing bacteria (SRB). Coupons exposed to the sterile medium were used as control. Electrochemical studies suggest a sharp drop in corrosion potential and increase in the anodic current for the coupons exposed to SRB. The austenite phase was found to be selectively attacked in presence of SRB for as-received material. Even though enhanced selective etching of austenite was noticed for thermally aged material, presence of actively corroding locations adjacent to the σ-phase protect the austenite phase. 相似文献
110.
This study reports the results of investigations on blends of silicone rubber and fluororubber based on tetrafluoroethylene/propylene/vinylidene fluoride terpolymer and the effects of replacement of silicone rubber and/or fluororubber in their 50/50 blend by the respective vulcanizate powders of known compositions. To simulate the aging condition of factory wastes, the silicone rubber or fluororubber vulcanizates were aged for 72 h at 200°C and then converted into powder by mechanical grinding. The fluororubber vulcanizate powder (FVP), mostly spherical in shape with average diameter varying between 2 and 10 μm, exists in a highly aggregated state displaying chainlike structures that, however, break down during blending with virgin rubbers. The silicone rubber vulcanizate powder (SVP) is irregular in shape, with larger particles in the range of 30–100 μm, and the smaller particles exist in highly aggregated chainlike structures, as in the case of FVP, which break down during milling to mostly spherical particles of 2–10 μm in diameter. Measurements of physical properties reveal that the blends of silicone rubber and fluororubber are technologically compatible. SEM photomicrographs of THF‐etched samples show the biphasic structure of the blends, in which the fluororubber forms the dispersed phase in a continuous silicone rubber matrix of lower viscosity. Replacement of silicone rubber in the 50/50 silicone rubber/fluororubber blend by its vulcanizate powder (SVP) increases the Mooney viscosity, but replacement of fluororubber in the blend by its vulcanizate powder (FVP) has little effect on the Mooney viscosity. Monsanto rheometric studies reveal that replacement of silicone rubber by SVP or fluororubber by FVP in the 50/50 silicone rubber/fluororubber blend increases the minimum rheometric torque but decreases the maximum torque, and the effect is more pronounced in the case of SVP. Furthermore, the replacement of silicone rubber in the blend by SVP causes a decline in the physical properties (25% replacement causing about 10% decline in properties, for example), whereas even 75% replacement of fluororubber by FVP has little effect on the physical properties. When both silicone rubber and fluororubber are partially replaced by SVP and FVP in the same blend, properties of the resulting blend composition are controlled more by SVP incorporation, whereas fluororubber replacement has only a marginal effect on blend properties. It is evident from dynamic mechanical spectra that the blends are immiscible in all compositions and addition of SVP or FVP does not affect the glass–rubber transitions of the constituent polymers. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2326–2341, 2001 相似文献