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991.
The study sought to understand the components of knowledge management strategy from the perspective of staff in UK manufacturing organizations. To analyse this topic, we took an empirical approach and collaborated with two manufacturing organizations. Our main finding centres on the key components of a knowledge management strategy, and the relationships between it and manufacturing strategy and corporate strategy. Other findings include: the nature of knowledge in manufacturing organizations; the relevance of (in)formal processes; top-down and bottom-up communication; taking ownership for information processes. We also make comments on the development of action plans for better knowledge management. The implications are that, for an integrated approach to knowledge management strategy in manufacturing organizations, involvement across the organization and at all levels is necessary. 相似文献
992.
In this paper, an attempt has been made to analyze the effects of various parameters, such as Soret and Dufour effects, chemical reaction, magnetic field, porosity on the fluid flow, and heat and mass transfer of an unsteady Casson fluid flow past a flat plate. Convective boundary conditions in heat and mass transfer and slip constant on velocity have been taken into account for analysis. The governing equations of the model have been solved numerically using the MATLAB program bvp4c. The impact of various parameters of the model on the velocity, temperature, and concentration profiles has been analyzed through different graphs. To get an insight into the physical quantities of engineering interest, viz, skin friction, Sherwood number, and Nusselt number, their numerical values have been computed for various parameters. The range of the parameters used in numerical computations are , , , , , , and . It has been noticed from the tabulated values that the skin friction gets enhanced with the increase in the thermal and solutal Grashof number, whereas its reverse effects have been observed with an increase in the Biot number. In limiting case, the present study is also compared with the available results in the literature. 相似文献
993.
994.
The effect of surface features on as-ground gears and the influence of BALINIT® C and Nb–S coatings on the initiation of micro-pitting damage have been examined in case-carburised and tempered S156 steel helical gears subjected to contact fatigue using back-to-back gear testing. The initiation of micro-pitting damage has been studied using scanning electron and optical microscopy examination. It has been observed that micro-cracks tend to initiate against the sliding direction preferentially from micro-valleys on the surface of as-ground gears, particularly when the depth of micro-valley is favourably oriented at an angle against the sliding direction. It has been found that the micro-pitting damage is drastically reduced in both coated gears. In BALINIT® C coated gears, the micro-scale surface irregularities are removed by a wear process resulting in a polished surface of the gear flank below the pitch diameter which is attributed to the effect of hard BALINIT® C coating. However, there is region of interface between the polished and unpolished regions of gear flank where there is small scale initiation of micro-pitting due to the absence of BALINIT® C coating at micro-valleys. In Nb–S coated gears, the coating tends to penetrate and fill-up the micro-valleys on as-ground surface modifying the gear flank surface. Hence, the micro-pits tend to initiate only at some micro-valley sites where the Nb–S coating is locally removed during running. This study shows that, both BALINIT® C and Nb–S coated gears show enhanced resistance to micro-pitting damage by removing localised stress concentration at micro-valleys present on as-ground gears. 相似文献
995.
Qiang Wang Jason U. Wallace Thomas Y.-H. Lee Lichang Zeng Jane J. Ou Shaw H. Chen 《Organic Electronics》2013,14(11):2925-2931
Instead of physical mixtures as bipolar charge transport media for organic electronics, chemical hybrids comprising non-conjugated spacers are explored to strive for miscibility and morphological stability. Bipolar TRZ-3Cz(MP)2 and TRZ-1Cz(MP)2 as well as unipolar C3-2TRZ(2tBu), C2-2TRZ(2tBu) and C3-2Cz(MP)2 were synthesized with propylene or ethylene spacers serving to decouple the Cz(MP)2 and TRZ moieties. Glassy films were prepared by vacuum sublimation for the characterization of transport properties using the photocurrent time-of-flight technique. The results indicate that both the TRZ:Cz(MP)2 ratio and the spacer length enable charge-carrier mobility to be modulated across orders of magnitude. The C2-2TRZ(2tBu) film exhibits the highest electron mobility of all the unipolar TRZ-based glassy films reported to date. 相似文献
996.
E.M. Jackson E.H. Aifer C.L. Canedy J.A. Nolde C.D. Cress B.D. Weaver I. Vurgaftman J.H. Warner J.R. Meyer J.G. Tischler S.A. Shaw C.R. Dedianous 《Journal of Electronic Materials》2010,39(7):852-856
The effects of 2 MeV proton irradiation on a set of four long-wave infrared type II superlattice photodiodes with various structures were studied. Changes were monitored in operating bias, quantum efficiency (QE), and dark current. Shifts in operating bias indicate that irradiation causes the superlattices to become more p-type, and decreases in QE are found to be consistent with a reduction in carrier lifetime. Leakage currents remain lower in graded-gap diodes at all fluences. 相似文献
997.
In recent years, a number of initiatives have been supported in Europe in the hydrogen energy sector. Communities can play an important role in the adoption process of these emerging technologies: supporting pre-commercial deployment, building public acceptance, and promoting innovation clusters, all of which lay the foundations for more widespread and sustained technology deployment. Participation by communities is hinged on the perceived contribution of technology adoption to community socio-economic and energy related goals, such as, climate change mitigation, air quality improvement, creation of new industries and businesses, exploitation of abundant renewable resources, and meeting growing energy needs. Hydrogen uptake in communities therefore stands to benefit development of the hydrogen energy sector and the communities themselves. This paper presents a methodology for evaluating the potential for successful large-scale hydrogen and fuel cell technology adoption—beyond demonstration projects—within defined community frameworks. This methodology can be a valuable tool, for community decision-makers and industry stakeholders alike, to evaluate and identify opportunities for large-scale hydrogen technology adoption. Results of applying the methodology are presented for three community types: islands, cities and regions. The work in this paper reflects work done within the frame of the European Commission-funded ‘Roads2HyCom’ project, Work Package 3.1 相似文献
998.
Crohn’s Disease (CD) and Rheumatoid Arthritis (RA) share some single nucleotide polymorphisms (SNPs) in protein tyrosine phosphatase non-receptor types 2 and 22 (PTPN2/22). Recently, we reported that clinical samples from CD and RA patients associated with PTPN2:rs478582 or PTPN22:rs2476601 genotypes were linked to overactive immune response and exacerbation of inflammation. Here, we investigated in vitro the effects of these SNPs in Jurkat T-cells using CRISPR-Cas9. All cells were evaluated for PTPN22/22 loss of function and effects on cell response. We measured gene expression via RT-qPCR and cytokines by ELISA. We also measured cell proliferation using a BrdU labeling proliferation ELISA, and T-cell activation using CD-25 fluorescent immunostaining. In PTPN2 SNP-edited cells, PTPN2 expression decreased by 3.2-fold, and proliferation increased by 10.2-fold compared to control. Likewise, expression of PTPN22 decreased by 2.4-fold and proliferation increased by 8.4-fold in PTPN22 SNP-edited cells. IFN-γ and TNF-α secretions increased in both edited cell lines. CD25 expression (cell activation) was 80.32% in PTPN2 SNP-edited cells and 85.82% in PTPN22 SNP-edited cells compared to 70.48% in unedited Jurkat T-cells. Treatment of PTPN2 and PTPN22-edited cells with a maximum 20 μM spermidine restored PTPN2/22 expression and cell response including cell proliferation, activation, and cytokines secretion. Most importantly, the effect of spermidine on edited cells restored normal expression and secretion of IFN-γ and TNF-α. The data clearly demonstrated that edited SNPs in PTPN2 or PTPN22 were associated with reduced gene expression, which resulted in an increase in cell proliferation and activation and overactive immune response. The data validated our earlier observations in CD and RA clinical samples. Surprisingly, spermidine restored PTPN2/22 expression in edited Jurkat T-cells and the consequent beneficial effect on cell response and inflammation. The study supports the use of polyamines dietary supplements for management of CD and in RA patients. 相似文献
999.
Retractable opposed needles are often used in reduced-gravity droplet combustion experiments to deploy droplets prior to ignition.
Needle retraction induces droplet shape oscillations and internal flows that can have important effects on subsequent droplet
behaviors. In the present paper, the unsteady flows and droplet shape oscillations associated with deployment needle retraction
are investigated using the commercial CFD software package Fluent. A volume-of-fluid method with a second-order upwind scheme
and a dual time stepping solver is employed to solve the conservation equations in 2-d and 3-d simulations of droplets prior
to ignition. A moving-mesh method is employed to model needle movements. Calculations indicate that rapid needle retraction
causes ligament formation between a droplet and a needle, with ligament breakage sometimes resulting in the formation of satellite
droplets. Needle retraction also induces droplet shape oscillations that rapidly decay, though significant internal flows
are predicted to remain within droplets even after droplet shape oscillations have damped to low levels. The calculations
indicate that the initial needle spacing can have important effects on droplet shape oscillations and internal flow characteristics.
Comparison of model predictions and experimental data is favorable. 相似文献
1000.
The partial least squares (PLS) regression technique was used to examine meat quality data derived from instruments (including Warner-Bratzler shear force and Instron Compression) and sensory panels. The data related to beef longissimus dorsi muscles collected during trials to study the effect of hot boning on meat quality. The univariate analysis of tenderness showed that over 60% of the variation in sensory tenderness, and almost 60% of the variation in sensory acceptability, could be explained from instrument variables and a consideration of boning and ageing time. Graphical displays from the analysis indicated that hot boning (either at 1 or 4 h) had little effect on meat quality. Graphical displays demonstrated a possible important effect of vacuum-pack ageing on acceptability. For this data set, it appears that samples of approximately equivalent tenderness differ in acceptability, depending on whether the samples have been aged for 1 or 4 weeks. This finding may have practical importance in attempts to predict eating quality (acceptability) from instrument measurements. Separate equations are necessary for products aged for different periods. ? 相似文献