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991.
This paper discusses the adoption of a pluralist theoretical framework – one that is also multiparadigmatic – for conducting and publishing information system (IS) research. The discussion is illustrated by a single case study involving the Australian cotton industry. The theoretical framework is informed by three sociological theories, each with its particular paradigmatic assumptions: structuration theory as a meta‐theory, and diffusion of innovations and gender relations as lower‐level theories from notionally opposing paradigms. Theoretical pluralism helped to produce rich findings, illuminating both the social nature of women farmers' roles, the materiality of the cotton farming context, the characteristics of the decision support systems in use and the recursive way in which human agency and institutional pressures shape each other. Because users of so‐called divergent paradigms often face criticism based on the incommensurability issue, one of the main contributions of this paper is to discuss the value of a pluralist and multiparadigmatic theoretical framework in dealing with complex IS social phenomena. 相似文献
992.
This paper describes the design and application of the Atmospheric Evaluation and Research Integrated model for Spain (AERIS). Currently, AERIS can provide concentration profiles of NO2, O3, SO2, NH3, PM, as a response to emission variations of relevant sectors in Spain. Results are calculated using transfer matrices based on an air quality modelling system (AQMS) composed by the WRF (meteorology), SMOKE (emissions) and CMAQ (atmospheric-chemical processes) models. The AERIS outputs were statistically tested against the conventional AQMS and observations, revealing a good agreement in both cases. At the moment, integrated assessment in AERIS focuses only on the link between emissions and concentrations. The quantification of deposition, impacts (health, ecosystems) and costs will be introduced in the future. In conclusion, the main asset of AERIS is its accuracy in predicting air quality outcomes for different scenarios through a simple yet robust modelling framework, avoiding complex programming and long computing times. 相似文献
993.
我国DSD酸行业推行清洁生产工艺的思考 总被引:3,自引:1,他引:3
戈建华 《精细与专用化学品》2003,11(5):3-5
2002年我国DSD酸的产量近2万t,占世界DSD酸总产量的40%,其中出口1.2万t,占世界DSD酸总贸易量的35%。我国DSD酸的现行合成路线仍采用传统的先污染后治理的模式,但也开发了一些清洁生产工艺,包括SO_3磺化、有机溶剂氧化、催化加氢还原等。目前企业采用现有清洁生产工艺工业化生产DSD酸还存在困难,作者建议应加强政策引导,强化管理,依靠科技组织进行示范,同时加强国际合作交流,引进技术。 相似文献
994.
The clay is treated with a reducing agent and an acid so as to obtain a clay containing various metal components with a variable‐valence state. Then, the clay is coprecipitated with natural rubber (NR) latex to prepare a vulcanized NR/clay composite. The degradation process of the NR/clay composite under hot air condition was studied dynamically by using a Fourier transform infrared spectrometer attaching an in situ sample cell and was also investigated using the TGA method. The test result obtained from the infrared spectrometry indicated that under low decomposition temperature, the decomposition products of the test samples mainly are ethylene, low molecular olefinic hydrocarbon, and carbonyl compounds. As the decomposition temperature rises, the low molecular olefinic hydrocarbon content decreases, the olefine with longer chain is formed, and a lot of alkane decomposition products are formed at the same time. When the content of the metal components with a variable‐valence state in clay such as Cu, Mn, Co, and Fe increases, the oxidation products containing the carbonyl group, the olefinic hydrocarbon, and CO2 in the decomposition product of the test sample also increase. The TGA result clearly shows a shoulder peak that appears by the side of the main peak on the DTG curve of NR/clay composite. With the increase in the content of metal components with variable‐valence state in clay, the initial degradation temperature of the test sample (T0), the degradation peak temperature (Tp1), and the final degradation temperature (Tf1) in first‐stage reaction, as well as the degradation peak temperature (Tp2) and the last final degradation temperature (Tf) in second‐stage reaction of all the test samples more or less shift to the direction of low temperature; besides, the activation energy (E) of the reaction of the test samples more or less decreases. This means that the metal components with variable‐valence state promote the oxidative degradation of the clay–rubber masterbatch. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3809–3815, 2006 相似文献
995.
Wang Jing Aidi Wu 《通讯和计算机》2014,(1):39-44
In this paper, we provide a super-resolution image reconstruction algorithm based on wavelet transform. Wavelet transform can separate high frequency and low frequency information of image. The more high frequency information can be obtained by using wavelet transform and the technique of image fusion. Meanwhile, reconstructed super-resolution image is produced by the iterative method. In iteration process, noise of image can be suppressed by applying method of wavelet threshold de-noising. The experiment results show that the algorithm can overcome the disadvantage of the classical interpolation method and effectively improve the resolution and PSNR of the image. 相似文献
996.
997.
我国烟草业是在专卖体制下实行统一领导、垂直管理、垄断经营的特殊行业,并且处于行政限制的垄断状态。这种专营专卖特点决定了其信息化建设与别的行业有所不同。近年来,随着烟草行业的不断整合、重组,其企业结构和管理、业务模式在不断发生变化,变得更加复杂,烟草业务的整合必然会带动烟草的信息化建设。在这样的趋势中,我国烟草企业的信息化建设必定是其在市场经济下提高企业竞争力的有效工具。 相似文献
998.
999.
随着软件行业的成熟,对软件定量评价的必要性增大。作者借鉴功能点分析法[1]结合自身多年系统测试的经验,提出一套软件外部质量[2]的评价模型,简便可行的解决了软件质量工程评价过程中因缺少实操性而难以量化的难题,为软件工程质量定量评价提供客观可行的方案。 相似文献
1000.
利用芬顿(Fenton)试剂的催化氧化性对焦化废水进行初步的处理,使其CODcr值除去率达80%以上,再用活性炭进行深度处理,使其CODcr值<40mg·L-1,总除去率达98%以上. 相似文献