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Allowing users to actively participate in the development and implementation of a new IS is supposed to increase their satisfaction with it. This type of participation, representing aspects relating to distributive and procedural justice, is increasingly impractical in current organizational settings, because many IS are used by thousands of employees and having them involved is impossible. Nonetheless, there are still benefits to be gained in other ways. Extrapolating from interactional justice, we proposed a passive participation method of engaging users. Its effect was tested in a large company in the USA and proved effective. Interactional justice, the perception of fairness in the way that people were treated at an interpersonal level, was found to increase user assessment of the value of their IS. Implications and expansions to interactional justice theory and how this antecedent affects IS implementation are discussed.  相似文献   
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Novel phospholipid (PL)-cyclosporine conjugates were prepared and studied as potential prodrugs for inflammatory bowel disease (IBD). Our approach relies on phospholipase A2 (PLA2), which is overexpressed in the inflamed intestinal tissues, as the prodrug activator to potentially release cyclosporine at the site of inflammation. PL-cyclosporine prodrug conjugates with methylene linkers of various lengths between the sn-2 position of the PL and cyclosporine were synthesized and evaluated for in vitro activation. Surprisingly, despite previous work indicating that conjugates with six methylene linkers between the lipid and drug would suffer rapid enzymatic hydrolysis, with cyclosporine this was not observed. However, compounds with longer linkers (n=10, 12 methylene units) display complete release of the drug by PLA2-catalyzed hydrolysis, thus demonstrating the importance and profound impact of structural fine-tuning. This study represents a proof-of-concept for our hypothesis and a first step towards a truly targeted IBD treatment with cyclosporine that could be administered throughout the GI tract.  相似文献   
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This research study examines associations between the business characteristics of manufacturing firms and their perceived benefits from ERP system investments. the perceived ERP benefits are measured at two levels: (1) an enterprise level and (2) a specific IT module level. the perceived value for ERP investments was consistently better explained at the specific IT module level.  相似文献   
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Test and evaluation of a solar powered gas turbine system   总被引:3,自引:1,他引:2  
This paper describes the test and the results of a first prototype solar powered gas turbine system, installed during 2002 in the CESA-1 tower facility at Plataforma Solar de Almería (PSA) in Spain. The main goals of the project were to develop a solar receiver cluster able to provide pressurized air of 1000 °C and solve the problems arising from the coupling of the receivers with a conventional gas turbine to demonstrate the operability of the system. The test set-up consists of the heliostat field of the CESA-1 facility providing the concentrated solar power, a pressurized solar receiver cluster of three modules of 400 kWth each which convert the solar power into heat, and a modified helicopter engine (OST3) with a generator coupled to the grid. The first test phase at PSA started in December 2002 with the goal to reach a temperature level of 800 °C at the combustor air inlet by the integration of solar energy. This objective was achieved by the end of this test phase in March 2003, and the system could be operated at 230 kWe power to grid without major problems. In the second test phase from June 2003 to August 2003 the temperature level was increased to almost 1000 °C. The paper describes the system configuration, the component efficiencies and the operation experiences of the first 100 h of solar operation of this very successful first test of a solar operated Brayton gas turbine system.  相似文献   
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Kar A  Patra A 《Nanoscale》2012,4(12):3608-3619
This feature article highlights the new development and current status of rare-earth (RE) based core-shell nanocrystals, which is one of the new classes of hybrid nanostructures. Attractive properties of rare-earth based nanomaterials include extremely narrow emission bands, long lifetimes, large Stoke's shifts, photostability and absence of blinking that can be exploited for biophotonic and photonic applications. Core-shell nanostructures have been attracting a great deal of interest to improve the luminescence efficiency by the elimination of deleterious cross-relaxation. The main focus of this feature article is to address the impacts of core-shell structures on the properties of lanthanide based nanocrystals including crystal phase, lattice strain, downconversion emission, upconversion emission and energy transfer. We describe general synthetic methodologies to design core-shell nanostructure materials. An interesting finding reported is that the local environment of an ion in the core-shell structure significantly affects the modifications of radiative and nonradiative relaxation mechanisms. Finally, a tentative outlook on future developments of this research field is given. Here, we attempt to identify the critical parameters governing the design of luminescent lanthanide based core-shell nanostructures.  相似文献   
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This paper details the adaptation and implementation of a proposed hierarchical model to the reliability assessment of LED-based luminaires. An Edison base ? 6 in., compatible can, downlight ? LED replacement bulb, cooled by active synthetic jets, is used as the test vehicle. Based on the identified degradation mechanisms and the experimentally obtained degradation rate of the cooling device, the reduction in the heat sink enhancement factor, and thus the increase in the LED junction temperature, is determined as a function of time. The degradation mechanisms of the dual-function power electronics – providing constant power to the LEDs and to the drivers of a series of synthetic jets – are also analyzed and serve as the basis for a hybrid model which combines these two effects on the luminaire lifetime. The lifetime of a prototypical luminaire is predicted from LED lifetime data using the degradation analyses of the synthetic jet and power electronics.  相似文献   
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