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91.
92.
目前,会展业作为一种有效的信息传播手段,以其直观、形象、高效、系统的独特方式,使参观者在不知不觉中,接受当代潮涌般的信息。因此,有效的传达信息在会展展示设计中显得尤为重要。本文从会展展示信息的传达要素、传达过程以及信息传达的方式与特点展开论述,希望对这一领域的设计实践具有一定的借鉴意义,利于今后提高展示设计信息传达的质和量。 相似文献
93.
雷鸿智 《数码设计:surface》2009,(12):173-175
李有行先生是我国著名的色彩教育家,国家二级教授,四川美术学院创办人,第一任校长。他开创的独特的色彩艺术教学体系在二十世纪六七八十年代中国各艺术院校中享有盛誉,被当时赞喻为"北有雷圭元,南当李有行"。他把早年留学法国学习绘画艺术的丰富经验与中国传统绘画艺术相融合,针对培养设计师为目标,创造了著名的李氏色彩教学体系。即从学习"图案艺术"到"绘画写生"再到"归纳色彩写生"完备的训练程序。在应用、设计学科内有效地制定了一整套以培养设计师为目标的"设计色彩"法,即作为艺术家和设计师双重身份的培养目标。 相似文献
94.
In this paper, we present an analysis and synthesis approach for guaranteeing that the phase of a single-input, single-output closed-loop transfer function is contained in the interval [−α,α] for a given α>0 at all frequencies. Specifically, we first derive a sufficient condition involving a frequency domain inequality for guaranteeing a given phase constraint. Next, we use the Kalman–Yakubovich–Popov theorem to derive an equivalent time domain condition. In the case where , we show that frequency and time domain sufficient conditions specialize to the positivity theorem. Furthermore, using linear matrix inequalities, we develop a controller synthesis approach for guaranteeing a phase constraint on the closed-loop transfer function. Finally, we extend this synthesis approach to address mixed gain and phase constraints on the closed-loop transfer function. 相似文献
95.
A modern problem from aerospace control involves the certification of a large set of potential controllers with either a single plant or a fleet of potential plant systems, with both plants and controllers being MIMO and, for the moment, linear. Experiments on a limited number of controller/plant pairs should establish the stability and a certain level of margin of the complete set. We consider this certification problem for a set of controllers and provide algorithms for selecting an efficient subset for testing. This is done for a finite set of candidate controllers and, at least for SISO plants, for compact infinite set. In doing this, the ν-gap metric will be the main tool. Computational examples are given, including one of certification of an aircraft engine controller. The overarching aim is to introduce truly MIMO margin calculations and to understand their efficacy in certifying stability over a set of controllers and in replacing legacy single-loop gain and phase margin calculations. 相似文献
96.
基于工作流的高校科研项目管理Petri网建模 总被引:2,自引:0,他引:2
科研项目管理是高校科研信息系统的核心部分之一,利用Petri网,对复杂的科研项目管理工作流程建模,解决高校信息化中较为复杂的科研项目管理工作流问题。以高校科研项目申请流程为例,给出了相关定义,分析和解决建模中遇到的几个问题。 相似文献
97.
The conversion of methane to higher hydrocarbons on single crystal Ru catalysts has been investigated using combined elevated-pressure kinetic measurements/surface science studies. The reaction consists of activation of methane on Ru(0001) and Ru(11¯20) surfaces to produce carbonaceous intermediates at temperatures
between 350 and 700 K and rehydrogenation of these species to ethane and propane at
370 K. It is found that under the reaction conditions employed, the maximum yield in ethane/propane production occurs at
500 K on both surfaces. Influence of the hydrogenation temperature on the production of ethane and propane is also examined. On Ru(0001), the yields of ethane and propane maximize at
= 400 K, whereas no maximum yield was observed on Ru(11
0) in the 300–500 K temperature range. Under optimum reaction conditions, hydrocarbon products consist of 16% ethane and 2% propane. High-resolution electron energy-loss spectroscopy (HREELS) has been used to identify various forms of hydrocarbonaceous intermediates following methane decomposition. An effort is made to relate the hydrocarbon intermediates identified by HREELS to the gas phase products observed in the elevated pressure experiments. 相似文献
98.
Pickering and Chater (P&C) maintain that folk psychology and cognitive science should neither compete nor cooperate. Each is an independent enterprise, with a distinct subject matter and characteristic modes of explanation. P&C's case depends upon their characterizations of cognitive science and folk psychology. We question the basis for their characterizations, challenge both the coherence and the individual adequacy of their contrasts between the two, and show that they waver in their views about the scope of each. We conclude that P&C do not so muchdiscover ascreate the gap they find between folk psychology and cognitive science. It is an artifact of their implausible and unmotivated attempt to demarcate the two areas, and of the excessively narrow accounts they give of each. 相似文献
99.
Open Science is a paradigm in which scientific data, procedures, tools and results are shared transparently and reused by society. The European Open Science Cloud (EOSC) initiative is an effort in Europe to provide an open, trusted, virtual and federated computing environment to execute scientific applications and store, share and reuse research data across borders and scientific disciplines. Additionally, scientific services are becoming increasingly data-intensive, not only in terms of computationally intensive tasks but also in terms of storage resources. To meet those resource demands, computing paradigms such as High-Performance Computing (HPC) and Cloud Computing are applied to e-science applications. However, adapting applications and services to these paradigms is a challenging task, commonly requiring a deep knowledge of the underlying technologies, which often constitutes a general barrier to its uptake by scientists. In this context, EOSC-Synergy, a collaborative project involving more than 20 institutions from eight European countries pooling their knowledge and experience to enhance EOSC’s capabilities and capacities, aims to bring EOSC closer to the scientific communities. This article provides a summary analysis of the adaptations made in the ten thematic services of EOSC-Synergy to embrace this paradigm. These services are grouped into four categories: Earth Observation, Environment, Biomedicine, and Astrophysics. The analysis will lead to the identification of commonalities, best practices and common requirements, regardless of the thematic area of the service. Experience gained from the thematic services can be transferred to new services for the adoption of the EOSC ecosystem framework. The article made several recommendations for the integration of thematic services in the EOSC ecosystem regarding Authentication and Authorization (federated regional or thematic solutions based on EduGAIN mainly), FAIR data and metadata preservation solutions (both at cataloguing and data preservation—such as EUDAT’s B2SHARE), cloud platform-agnostic resource management services (such as Infrastructure Manager) and workload management solutions. 相似文献
100.
技术预见是制定科技发展战略和科技政策的重要基础,德尔菲调查是技术预见中最常用的方法。本研究通过文献分析、专家建议、会议讨论等方法,从大气污染防治、水污染防治、固体废弃物污染防治与资源化、土壤污染防治、生态保护与恢复、环境监测预警与风险控制、资源利用与清洁生产7个子领域提出我国环境工程领域的45项备选技术。根据德尔菲法的调查结果,初步筛选出2035年我国环境工程科技发展的关键技术、共性技术以及颠覆性技术,分析了技术实现时间、发展水平与制约因素,为未来20年我国环境工程科技发展战略和目标的制定提供参考。 相似文献