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Daniela Fogli Antonio Piccinno Stefan Carmien Gerhard Fischer 《Behaviour & Information Technology》2020,39(1):27-46
ABSTRACTThe digital age of the future is ‘not out there to be discovered’, but it needs to be ‘designed’. The design challenge has to address questions about how we want to live, work, and learn (as individuals and as communities) and what we value and appreciate, e.g.: reflecting on quality of life and creating inclusive societies. An overriding design trade-off for the digital age is whether new developments will increase the digital divide or will create more inclusive societies. Sustaining inclusive societies means allowing people of all ages and all abilities to exploit information technologies for personally meaningful activities. Meta-design fosters the design of socio-technical environments that end-user developers can modify and evolve at use time to improve their quality of life and favour their inclusion in the society. This paper describes three case studies in the domain of assistive technologies in which end users themselves cannot act as end-user developers, but someone else (e.g.: a caregiver or a clinician) must accept this role requiring multi-tiered architectures. The design trade-offs and requirements for meta-design identified in the context of the case studies and other researchers’ projects are described to inform the development of future socio-technical environments focused on social inclusion. 相似文献
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The paper concerns an analysis of an equilibrium problem for 2D elastic body with two semirigid inclusions. It is assumed that inclusions have a joint point, and we investigate a junction problem for these inclusions. The existence of solutions is proved, and different equivalent formulations of the problem are proposed. We investigate a convergence to infinity of a rigidity parameter of the semirigid inclusion. It is proved that in the limit, we obtain an equilibrium problem for the elastic body with a rigid inclusion and a semirigid one. A parameter identification problem is investigated. In particular, the existence of a solution to a suitable optimal control problem is proved. 相似文献
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The NW‐SE trending Cantarell structure in the Gulf of Campeche hosts the largest oilfield in Mexico. The oil occurs predominantly in latest Cretaceous – earliest Tertiary breccias with subsidiary reserves in Upper Jurassic (Oxfordian and Kimmeridgian) and Lower Cretaceous oolitic and partially dolomitized limestones, dolomites and shaly limestones. Cantarell has been interpreted both as a fold‐and‐thrust zone and as a dextral transpressional structure. Analysis of structure contours at 100m intervals, on the tops of the Tertiary breccia and the Kimmeridgian (Upper Jurassic) dolomite, indicates that the structure is an upright cylindrical fold with gently plunging conical terminations; there is also a conical portion in the central part of the structure. The axes of the central, NW and SE cones are subvertical. This geometry indicates that the two fold terminations and the central cone are aprons rather than points, with the NW and central cone axes intersecting the cylindrical fold axis at the point where the geometry switches from conical to cylindrical. The apical angle (i.e. the angle between the fold and cone axes) varies as follows: (i) in the NW cone, it is ~70° in the breccia and ~76° in the Kimmeridgian dolomite; (ii) in the central cone, it is ~77° in the breccia and ~73° in the Kimmeridgian dolomite; and (iii) in the SE cone, it is ~64° in the breccia and ~57° in the Kimmeridgian dolomite. This indicates that whereas the fold opens with depth in the NW cone, it tightens with depth in the central and SE cones. Assuming a parallel fold geometry, these apical angles indicate an increase in volume in the NW cone (i.e. larger hydrocarbon reservoirs), compared to the central and SE cones. Theoretical considerations indicate that the curvature increases dramatically towards the point of the cone. In the case of the Cantarell structure, the apices of the cones are located at the conical‐cylindrical fold junctions, where the highest curvature may have resulted in a higher degree of fracturing. The coincidence of maximum curvature and the intersection of the conical and cylindrical fold axes in the fold culminations with porous and permeable reservoir rocks may have made these locations favourable for the accumulation of hydrocarbons. 相似文献
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结合芳烃联合装置的发展形势,通过对国内某4套典型芳烃联合装置运行能耗的构成进行分析,确定该类装置的主要能耗在于燃料、电和蒸汽的消耗。总结了目前国内外常用的芳烃联合装置节能降耗方法,利用实际经验和调研结果,从采用新型吸附剂、采用单台吸附塔新工艺、采用轻质解吸剂替代对二乙苯(PDEB)、优化吸附塔运行参数、加热炉节能优化和选用高效节能设备等角度探讨芳烃联合装置的节能降耗方法。芳烃联合装置节能降耗应该由设计单位和生产单位紧密结合,在设计阶段就应充分考虑生产过程面临的问题,充分优化工艺路线、方案和设备设计,尽可能降低装置的能耗。同样,装置运行过程中,生产部门应标准化、精细化管理,优化日常操作,从而进一步降低装置的操作能耗。 相似文献
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催化裂解多产丙烯新技术 总被引:6,自引:0,他引:6
介绍了国内外利用蜡油或常压渣油等重质原料的增产丙烯技术CPP,ARGG FDFCC和TSRMP;还介绍了利用富含烯烃的混合碳四和催化裂化汽油等轻质原料的增产丙烯技术OCP,Propylur,Superflex,OCT,Meta-4和BASF公司的丁烯歧化工艺技术. 相似文献