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101.
In this paper, we focus on a critical aspect of work in organizations: using information in work tasks which is provided by information systems (IS) such as enterprise content management (ECM) systems. Our study based on the IS success model, 34 interviews, and an empirical study of 247 ECM system users at a financial service provider indicates that it is appropriate to differentiate between contextual and representational information quality as two information quality dimensions. Furthermore, we reveal that in addition to system quality, the two information quality dimensions are important in determining end-user satisfaction, which in turn influences the manifestation of workarounds. Our study also finds that employees using workarounds to avoid an ECM system implemented several years is negatively related to individual net benefits of the ECM system. Hence, we conclude that when investigating large-scale IS such as ECM systems, it is important to differentiate among information quality dimensions to more deeply understand end-user satisfaction and the resulting manifestation of workarounds. Moreover, this research guides organizations in implementing the most appropriate countermeasures based on the importance of either contextual or representational information quality. 相似文献
102.
Tim MatthewsAuthor Vitae 《Computer Fraud & Security》2012,2012(5):18-20
103.
By combining heat and power generation, mini‐combined and micro‐combined heat and power systems (MCHP) provide an efficient, decentralised means of power generation that can complement the composition of the electricity generation mix. Dynamic tools capable of handling transient system behaviour are required to assess MCHP efficiency beyond a mere static analysis based on steady‐state design parameters. Using a simulation of a cogeneration system, we combine exergetic definitions for different operational system states to quantify the overall system efficiency continuously over the whole period of operation. The concept of exergy allows direct comparison of different forms of energy. A sensitivity analysis was performed where we quantified the effect on MCHP overall performance under varying engine rotational speed, thermal energy storage size and fluid storage temperature in a range of MCHP simulations. We found that the exergetic quantity of natural gas used by the MCHP decreased slightly at higher engine speeds (?2% to ?4%). While the total amount of electricity generated is almost constant across the range of different engine output, more thermal exergy (up to +21%) can be recovered when the engine is operating at elevated speeds. Furthermore, selection of specific optimal thermal storage fluid temperatures can aid in improving system efficiency. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
104.
Nano design for macroscopic coatings – new application potentials by PVD coatings up to 100 μm thickness Non-homogeneous coatings still limit the application of thicker layers due to defect growth and irregular layer thickness distribution along the surface of complex shaped components. Therefore, the layer thickness is usually limited to about 10 μm. In order to limit the surface roughness by the growing layer, multilayer coating systems are deposited by highly ionized plasmas. This allows significantly smoother layers to be produced, which until now could only be produced by mechanical finishing. Furthermore, by combining selected material systems and targeted parameter selection, structures can be deposited during coating, especially on edges, which result in a reduction of the cutting edge radius. In future, edge geometries should therefore be able to be specifically adjusted through the coating process. 相似文献
105.
106.
Molecular Heterojunctions of Oligo(phenylene ethynylene)s with Linear to Cruciform Framework
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![点击此处可从《Advanced functional materials》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Zhongming Wei Tim Hansen Marco Santella Xintai Wang Christian R. Parker Xingbin Jiang Tao Li Magni Glyvradal Karsten Jennum Emil Glibstrup Nicolas Bovet Xiaowei Wang Wenping Hu Gemma C. Solomon Mogens Brøndsted Nielsen Xiaohui Qiu Thomas Bjørnholm Kasper Nørgaard Bo W. Laursen 《Advanced functional materials》2015,25(11):1700-1708
Electrical transport properties of molecular junctions are fundamentally affected by the energy alignment between molecular frontier orbitals (highest occupied molecular orbital (HOMO) or lowest unoccupied molecular orbital (LUMO)) and Fermi level (or work function) of electrode metals. Dithiafulvene (DTF) is used as substituent group to the oligo(phenylene ethynylene) (OPE) molecular wires and different molecular structures based on OPE3 backbone (with linear to cruciform framework) are achieved, with viable molecular orbitals and HOMO–LUMO energy gaps. OPE3, OPE3–DTF, and OPE3–tetrathiafulvalene (TTF) can form good self‐assembled monolayers (SAMs) on Au substrates. Molecular heterojunctions based on these SAMs are investigated using conducting probe–atomic force microscopy with different tips (Ag, Au, and Pt) and Fermi levels. The calibrated conductance values follow the sequence OPE3–TTF > OPE3–DTF > OPE3 irrespective of the tip metal. Rectification properties (or diode behavior) are observed in case of the Ag tip for which the work function is furthest from the HOMO levels of the OPE3s. Quantum chemical calculations of the transmission qualitatively agree with the experimental data and reproduce the substituent effect of DTF. Zero‐bias conductance, and symmetric or asymmetric couplings to the electrodes are investigated. The results indicate that improved fidelity of molecular transport measurements may be achieved by systematic studies of homologues series of molecular wires applying several different metal electrodes. 相似文献
107.
This article explores the historical context, process and result of introducing and implementing ‘new’ town planning in early post‐war Taiwan. The two so‐called ‘garden cities’ are examined: Jhong‐Sing New Village and Yonghe City, both of which were formulated in the mid‐1950s by the same group of local planners. It reveals that the assumed necessity of importing Western planning paradigms arose from the abrupt escalation of urban concentration caused by the late 1940s mass migrations from China. To cope with this unprecedented population growth, planning profession was swiftly established. The novice planners, in search of a reference for developing ‘new’ towns to decentralise excessive urbanisation, modelled their ‘new’ town planning on English suburban morphology. In the absence of an input of external expertise, the planners appeared to mistake aesthetic order and pastoral imagery of low‐density residential development in England as practically viable solutions to the pressing urban problems in Taiwan. In a false hope that adopting Western ideas and practices would quickly lead the island to a better world, Taiwan initiated the importation of planning paradigms. This planning transfer not only evidently manifests a mode of ‘borrowing’ in post‐colonial countries in international diffusion but also re‐articulates the disseminating nature of modern planning and the existence of one‐direction flows characterising the global dynamics of diffusion in the twentieth century. 相似文献
108.
Tim Knudsen 《Planning Perspectives》2013,28(3):297-310
Influences on early Danish planning came from a variety of international sources. The Big City paradigm was mainly taken over from German planning, sometimes varied with elements from Haussmann and American cities. Later inspiration from Camillo Sitte and from the English Garden City movement was combined with traditional Danish small town values into a competing paradigm. The engineers mainly adhered to the Big City paradigm, whilst the architects were the chief proponents of the English inspiration, and these two paradigms have been used as tools of rivalry between the two professions. This discord might in the long run have led to a weakening of the planners’ political influence. 相似文献
109.
The numbers of English public houses or “pubs” have reduced significantly in the last two decades. Politicians have called on the planning system to resist their closure but, at the same time, demand further controls over high-street bars. This paper explores the reasons for the decline and the rationale for supporting the continuation of the “traditional” English pub. Using evidence drawn from a wider study of the relationships between places and youth drinking cultures, the paper discusses young adults' use of pubs. While recognising the adverse effects of heavy drinking, arguments are put forward in support of the traditional pub as a site for restrained and responsible social interaction for young adults. The paper discusses the issues this raises for the UK planning system in the context of responsibilities for social sustainability and public health. 相似文献
110.
Synthesis and Crystal Structure Characterization of Oxysilicate Apatites for Stabilization of Sr and Rare‐Earth Elements
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Jingxian Wang Fengxia Wei Soo Min Lim Erjia Liu Claude Guet Tim White ZhiLi Dong 《Journal of the American Ceramic Society》2016,99(5):1761-1768
Strontium (Sr) containing rare‐earth oxysilicate apatite AI4AII6(SiO4)6O2 is considered a good matrix to accommodate radionuclide as its cation sites can incorporate lanthanide elements other than Sr. Here, we report a study on the synthesis of Nd8Sr2(SiO4)6O2 and Yb8Sr2(SiO4)6O2, which adopt P63/m apatite symmetry, as well as the characterization of crystallographic structures using X‐ray diffraction and electron microscopy. It is found that AI position is shared by Nd, Yb and Sr, and AIO6 polyhedra are face‐connected, forming column structures, which are linked to SiO4 tetrahedra, creating continuous channels. The Rietveld refinement shows that Nd and Yb prefer the AII position in the channel. The twisted angle of adjacent triangle faces in an AI‐O polyhedron along [001] is a critical parameter to identify the channel volume and its value varies when different cations are incorporated. The twisted angles for Nd‐apatite and Yb are 24.2° and 22.7° The findings provide a new insight into nuclear waste stabilization by apatite‐type structure. 相似文献