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31.
The computational complexity of numerical models can be broken down into contributions ranging from spatial, temporal and stochastic resolution, e.g., spatial grid resolution, time step size and number of repeated simulations dedicated to quantify uncertainty. Controlling these resolutions allows keeping the computational cost at a tractable level whilst still aiming at accurate and robust predictions. The objective of this work is to introduce a framework that optimally allocates the available computational resources in order to achieve highest accuracy associated with a given prediction goal. Our analysis is based on the idea to jointly consider the discretization errors and computational costs of all individual model dimensions (physical space, time, parameter space). This yields a cost-to-error surface which serves to aid modelers in finding an optimal allocation of the computational resources (ORA). As a pragmatic way to proceed, we propose running small cost-efficient pre-investigations in order to estimate the joint cost-to-error surface, then fit underlying complexity and error models, decide upon a computational design for the full simulation, and finally to perform the designed simulation at near-optimal costs-to-accuracy ratio. We illustrate our approach with three examples from subsurface hydrogeology and show that the computational costs can be substantially reduced when allocating computational resources wisely and in a situation-specific and task-specific manner. We conclude that the ORA depends on a multitude of parameters, assumptions and problem-specific features and, hence, ORA needs to be determined carefully prior to each investigation. 相似文献
32.
This paper uses four case studies to emphasize the fact that field engineering decisions cannot be made without a full understanding of all the technical problems involved. Two of the studies are taken from conventional design-bid-build projects and two are taken from design-build projects in which the ability to strongly influence design in the interest of construction efficiency places a new and increased emphasis on construction and field engineering skills. The cases also show that field engineering decisions frequently address new and unexpected realities, changed conditions, and transient loads, and thus they require high levels of understanding, technical analysis, and creative thought. We emphasize the need for universities and construction engineering programs to develop graduates who are capable of integrating design and construction considerations throughout the project delivery process. We also urge programs to continue to focus strongly on field engineering as the foundation for success in an increasingly complex and technically driven construction industry. 相似文献
33.
After nearly 48 years of failure to create the EU patent, language issues and the design of a centralised patent-litigation court still dominate headlines. But behind these issues there are high financial stakes and control power to play for. The recent EU Council deal on an ‘enhanced’ European patent system does not solve the above problems, and has not eliminated lingering governance issues. The risk for Europe is that a final patent agreement might be reached that does not cure the system of its major ills, and thus does not bring about any significant improvement for those that need it most: entrepreneurs and innovative companies starting out on the innovation process. The creation of an effective single EU patent requires (i) English-only post-grant translation, (ii) the end of nationally granted patents, (iii) phasing-out of the current ‘European patent’, (iv) lower fees for young innovative companies, and (v) a radical shake-up of the governance of the European Patent Office. 相似文献
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本文作者结合自身工作实际经验,对施工阶段监理的投资控制一些相关问题进行简单的论述,可供同行借鉴。 相似文献
37.
漳州的气候条件对于建筑节能来说,主要是夏季隔热的问题,本文对漳州目前采用的住宅外墙保温施工的问题进行了粗浅的探讨。 相似文献
38.
纪念馆兼有文化性和时代性,它既要强调文化传统和当地文脉,又要体现展览建筑的时代特色。建筑设计应注重简洁、朴实和高品格,而不在于材料、装修的豪华及过分做作的造型。该方案设计采用覆土建筑形式,同时与生态、节能联系在一起,充分利用建筑空间,营造宜人的展览氛围。 相似文献
39.
文章结合杭州西溪新天地的设计分析,从空间序列的建构、文化氛围的建构以及其中人员活动的建构等方面,讨论了现代开发方式与传统街坊理念之间的平衡之道。 相似文献
40.
通过对冶金建设工程中预结算审核工作进行了系统的阐述,指出影响预结算审核工作准确性的因素,提出了解决问题的方法,对更加合理地确定工程造价及保证项目目标管理的实现起到了积极的意义。 相似文献