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1.
Systemic Practice and Action Research - Most of the traditional technology acceptance models revolve around information systems (IS)/information technology (IT) adoption at individual user level....  相似文献   
2.
The purpose of this paper is to investigate the pricing European call option valuation problems under the exercise price,maturity,risk-free interest rate,and the volatility function. An advance methodology,Chebyshev simulated annealing neural network(Ch SANN),is enforced for the Black-Scholes(B-S) model with boundary conditions. Our scheme is stable and easy to implement on B-S equation,for arbitrary volatility and arbitrary interest rate values. Also,the comparative results demonstrate that the attained approximate solutions are converging towards the exact solution. The graphical results show that the increasing flow of the European call option as the exponential increase takes place in assets. The presented algorithm can be further applied to other financial models with certain boundary conditions. The algorithm of the method shows that the approach can also be easily employed on time-fractional B-S equation.  相似文献   
3.
In this article, I will view realist and non-realist accounts of scientific models within the larger context of the cultural significance of scientific knowledge. I begin by looking at the historical context and origins of the problem of scientific realism, and claim that it is originally of cultural and not only philosophical, significance. The cultural significance of debates on the epistemological status of scientific models is then related to the question of ‘intelligibility’ and how science, through models, can give us knowledge of the world by presenting us with an ‘intelligible account/picture of the world’, thus fulfilling its cultural-epistemic role. Realists typically assert that science can perform this role, while non-realists deny this. The various strategies adopted by realists and non-realists in making good their respective claims, is then traced to their cultural motivations. Finally I discuss the cultural implications of adopting realist or non-realist views of models through a discussion of the views of Rorty, Gellner, Van Fraassen and Clifford Hooker on the cultural significance of scientific knowledge.  相似文献   
4.
新型的溶胶—凝胶毛细管气相色谱柱除了具有热稳定性高及分离效果好的特点外,此色谱柱的柱容量(sample capacity)数倍于传统的用静态法涂渍固定相并用交联反应使之固载化的色谱柱的柱容量.在两种不同的色谱柱上,逐渐增加试样的进样量,柱效率随之变化.进样量对柱效率的影响清楚地表明了溶胶—凝胶柱的柱容量远高于传统柱.  相似文献   
5.
This paper is concerned with time-series forecasting based on the linear regression model in the presence of AR(1) disturbances. The standard approach is to estimate the AR(1) parameter, ρ, and then construct forecasts assuming the estimated value is the true value. We introduce a new approach which can be viewed as a weighted average of predictions assuming different values of ρ. The weights are proportional to the marginal likelihood of ρ. A Monte Carlo experiment was conducted to compare the new method with five more conventional predictors. Its results suggest that the new approach has a distinct edge over existing procedures.  相似文献   
6.
This study provides details of the energy management architecture used in the Goldwind microgrid test bed. A complete mathematical model, including all constraints and objectives, for microgrid operational management is first described using a modified prediction interval scheme. Forecasting results are then achieved every 10 min using the modified fuzzy prediction interval model, which is trained by particle swarm optimization.A scenario set is also generated using an unserved power profile and coverage grades of forecasting to compare the feasibility of the proposed method with that of the deterministic approach. The worst case operating points are achieved by the scenario with the maximum transaction cost. In summary, selection of the maximum transaction operating point from all the scenarios provides a cushion against uncertainties in renewable generation and load demand.  相似文献   
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少数民族语言文献资源是民族艺术文献资料、民族史学研究、宗教文化等的重要载体,对它们的收集与整理是建立健全少数民族文献资源体系、提高少数民族语言文献资源共享性的重要保障。阐述了新疆农业大学图书馆少数民族语言特色文献资源现状和存在的问题,提出了关于管理与发展新疆少数民族语言特色文献资源库的建议。  相似文献   
9.
The dissolution kinetics of a Nigerian chalcopyrite ore in hydrochloric acid was studied in this article. Acid concentration, reaction temperature, and ore particle size were chosen as experimental parameters. The chemical and morphological studies of the ore before and after leaching at optimal conditions were carried out by X-ray diffraction (XRD) and scanning electron microscopy (SEM). It is revealed that increasing the acid concentration and system temperature and decreasing the ore particle size greatly enhances the dissolution rate. The dissolution kinetics was found to follow the shrinking core model for the diffusion control mechanism where the activation energy (Ea) of 32.92 kJ·mol?1 was obtained for the process and supported by morphological changes at a higher dissolution of 91.33%.  相似文献   
10.
Multiferroics exhibit unique combination of ferroic properties,simultaneously.For instance,in BiFeO3,magnetic and electric properties co-exist.In this work,BiFeO3 and Sr-doped BiFeO3 samples with general formula,Bi1-x Srx FeO3(x=0.00,0.05,0.10,0.20,and 0.30) were synthesized by sol-gel auto-combustion technique,in order to investigate these ferroic properties.The samples were confrmed to have perovskite type rhombohedral structure,characteristic of BiFeO3.A dilute phase of Bi2Fe4O9was also found in all the Sr-doped samples.The micrographs of the palletized samples revealed that minutely doped Sr might not have any effect on the morphology of the samples.Frequency dependent dielectric measurements were carried out at room temperature for all the samples from 100 Hz to 1 MHz.The dielectric constant of un-doped sample at low frequency was 52 which decreased with increasing Sr doping.An enhancement of magnetic properties was observed with increasing the Sr contents.Pure BiFeO3 material was observed to have the least value of remanent magnetization.As the Sr2+ tions were doped in BiFeO3,its magnetization and remanence were increased to 0.867 emu/g and 0.175 emu/g,respectively,at x=0.30.  相似文献   
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