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排序方式: 共有1042条查询结果,搜索用时 15 毫秒
31.
Anita Lee-Post 《国际生产研究杂志》2013,51(4):793-810
Past research in part family identification has focused mainly on the development of efficient procedures for manufacturing-oriented part family formation in which similarities among parts are established primarily on machine or operation requirements. While these part families are essential in cellular manufacturing, they are not well suited for other areas of production, in particular, part design and process planning. A new part family identification technique using a simple genetic algorithm is proposed in this paper to first determine a set of part family differentiating attributes, and second to use these attributes to guide the formation of part families. The technique is implemented in C using a SUN SPARC workstation 1+. Empirical analyses of the technique on both artificially generated data and a real application are performed and discussed. 相似文献
32.
Understanding the individual's collectivistic orientations toward group goals and task activities is critical for developing cooperative and productive teams. The complex environment of modern construction, where the emphasis shifts from individually oriented to team‐based work, has led to many challenges. There are important issues of cooperative behaviours in a world of cultural pluralism in which interpersonal cooperation is juxtaposed with organizational citizenship behaviour. Behaviours of construction project participants are important manifestations of culture that are dependent upon norms, values and beliefs. Certain organizational cultures support individualistic behaviours while others emphasize the benefits to the collective whole. Collectivistic orientation is examined as the cultural dimension of individualism‐collectivism (IC) and found to be related to organizational citizenship behaviour (OCB) where the correlations of IC and most OCB variables are significant for quantity surveyors in Hong Kong. Generally, the (more) individualistic persons are less likely to exhibit organizational citizenship behaviours. 相似文献
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35.
Biosorption of nickel ions from aqueous solutions by natural and modified peanut husks: equilibrium and kinetics 下载免费PDF全文
Katerina Atkovska Burevska Hamdije Memedi Kiril Lisichkov Stefan Kuvendziev Mirko Marinkovski Gordana Ruseska Anita Grozdanov 《Water and Environment Journal》2018,32(2):276-284
The toxicity and non‐biodegradation of heavy metals, as well as their tendency to accumulate in the soils, water resources and the living organisms, makes them the significant environmental pollutants. Therefore, the reduction and elimination of heavy metal ions from aqueous systems is very important from the ecological, nutritional and environmental reasons. The aim of this study is to investigate whether the natural peanut husks, an agricultural waste, and their chemically modified form are capable to remove Ni(II) ions from aqueous solutions using batch method and to compare their efficiency. The effects of the mass of the natural peanut husks and the initial pH of the solution were studied to find the optimal conditions for maximal removal of Ni(II) ions. MATLAB/Curve Fitting Toolbox was implemented to determine the adequate adsorption isotherm as well as to optimise the equilibrium state of the investigated systems. 相似文献
36.
Internalization and Accumulation in Dendritic Cells of a Small pH‐Activatable Glycomimetic Fluorescent Probe as Revealed by Spectral Detection 下载免费PDF全文
Prof. Zoran Arsov Prof. Urban Švajger Prof. Janez Mravljak Prof. Stane Pajk Anita Kotar Dr. Iztok Urbančič Prof. Janez Štrancar Prof. Marko Anderluh 《Chembiochem : a European journal of chemical biology》2015,16(18):2660-2667
DC‐SIGN, an antigen‐uptake receptor in dendritic cells (DCs), has a clear role in the immune response but, conversely, can also facilitate infection by providing entry of pathogens into DCs. The key action in both processes is internalization into acidic endosomes and lysosomes. Molecular probes that bind to DC‐SIGN could thus provide a useful tool to study internalization and constitute potential antagonists against pathogens. So far, only large molecules have been used to directly observe DC‐SIGN‐mediated internalization into DCs by fluorescence visualization. We designed and synthesized an appropriate small glycomimetic probe. Two particular properties of the probe were exploited: activation in a low‐pH environment and an aggregation‐induced spectral shift. Our results indicate that small glycomimetic molecules could compete with antigen/pathogen for binding not only outside but also inside the DC, thus preventing the harmful action of pathogens that are able to intrude into DCs, for example, HIV‐1. 相似文献
37.
Malte Steiner Lutz Claes Anita Ignatius Frank Niemeyer Ulrich Simon Tim Wehner 《Journal of the Royal Society Interface》2013,10(86)
Numerical models of secondary fracture healing are based on mechanoregulatory algorithms that use distortional strain alone or in combination with either dilatational strain or fluid velocity as determining stimuli for tissue differentiation and development. Comparison of these algorithms has previously suggested that healing processes under torsional rotational loading can only be properly simulated by considering fluid velocity and deviatoric strain as the regulatory stimuli. We hypothesize that sufficient calibration on uncertain input parameters will enhance our existing model, which uses distortional and dilatational strains as determining stimuli, to properly simulate fracture healing under various loading conditions including also torsional rotation. Therefore, we minimized the difference between numerically simulated and experimentally measured courses of interfragmentary movements of two axial compressive cases and two shear load cases (torsional and translational) by varying several input parameter values within their predefined bounds. The calibrated model was then qualitatively evaluated on the ability to predict physiological changes of spatial and temporal tissue distributions, based on respective in vivo data. Finally, we corroborated the model on five additional axial compressive and one asymmetrical bending load case. We conclude that our model, using distortional and dilatational strains as determining stimuli, is able to simulate fracture-healing processes not only under axial compression and torsional rotation but also under translational shear and asymmetrical bending loading conditions. 相似文献
38.
Urszula Krupa-Kozak Natalia Drabińska Cristina M. Rosell Costantino Fadda Andrzej Anders Tomasz Jeliński Anita Ostaszyk 《International Journal of Food Science & Technology》2019,54(4):1121-1129
Broccoli by-products, in particular leaves, are rich sources of nutritional and bioactive components thus could constitute a valuable food additive. Although an upsurge in quantity of gluten-free products is observed further studies are required on improvement of their nutritional quality and palatability. This study aimed to investigate the influence of broccoli leaf powder (BLP) on dough behaviour, and technological characteristics and sensory quality of gluten-free mini sponge cake (GFS). Broccoli leaf powder replaced an equivalent amount (2.5%, 5%, 7.5%; w/w) of corn and potato starches in GFS formulation. Applied BLP increased the instrumental firmness of GFS but sensorial attributes (elasticity, crustiness, mastication and adhesiveness) were similar to the control. All broccoli GFS were vividly green, had small size pores properly distributed. Among them, sample with 2.5% BLP was distinguished for its desirable sensory quality, despite a slightly perceived cabbage aroma and taste. Moderate amount of BLP allows to preserve a good quality GFS improving its attractiveness and palatability. 相似文献
39.
Recombinant adeno-associated virus targets passenger gene expression to cones in primate retina 总被引:2,自引:0,他引:2
Mancuso K Hendrickson AE Connor TB Mauck MC Kinsella JJ Hauswirth WW Neitz J Neitz M 《Journal of the Optical Society of America. A, Optics, image science, and vision》2007,24(5):1411-1416
Recombinant adeno-associated virus (rAAV) is a promising vector for gene therapy of photoreceptor-based diseases. Previous studies have demonstrated that rAAV serotypes 2 and 5 can transduce both rod and cone photoreceptors in rodents and dogs, and it can target rods, but not cones in primates. Here we report that using a human cone-specific enhancer and promoter to regulate expression of a green fluorescent protein (GFP) reporter gene in an rAAV-5 vector successfully targeted expression of the reporter gene to primate cones, and the time course of GFP expression was able to be monitored in a living animal using the RetCam II digital imaging system. 相似文献
40.
This paper studies the first-principles calculations of the effect of hydrostatic pressure on the structural, electronic and magnetic properties of Ga0.75Cr0.25As dilute magnetic semiconductor in zb (B3) phase. High-pressure behaviour of Ga0.75Cr0.25As has been investigated between 0 and 100 GPa. The calculations have been performed using DFT as implemented in code SIESTA using LDA + U as an exchange-correlation (XC) potential. The study of band structures shows half-metallic ferromagnetic nature with 100% spin polarization. Under application of external pressure, the valence band and conduction band are shifted from their positions which lead to modification of electronic structure. 相似文献