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71.
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
72.
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
73.
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
74.
程乐 《计算机工程与应用》2008,44(34):44-46
通过模拟蟑螂的觅食行为,提出蟑螂算法(Cockroach Swarm Optimization,CSO)。算法充分利用了蟑螂社会的平等特性和群体智慧。食物再分配、回巢等策略的使用使算法具有较强的全局搜索和局部搜索能力。以TSP问题为例对算法进行仿真测试,实验证明算法有效且优于存在的离散粒子群算法(Discrete Particle Swarm Optimization,PSO)。 相似文献
75.
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
76.
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
77.
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
78.
《低温学》2016
A sub Kelvin Active Magnetic Regenerative Refrigerator (AMRR) is being developed at the University of Wisconsin – Madison. This AMRR consists of two circulators, two regenerators, one superleak, one cold heat exchanger, and two warm heat exchangers. The circulators are novel non-moving part pumps that reciprocate a superfluid mixture of 4He–3He in the system. Heat from the mixture is removed within the two regenerators of this tandem system. An accurate model of the regenerators in this AMRR is necessary in order to predict the performance of these components, which in turn helps predicting the overall performance of the AMRR system. This work presents modeling methodology along with results from a 1-D transient numerical model of the regenerators of an AMRR capable of removing 2.5 mW at 850 mK at cyclic steady state. 相似文献
79.
Markdown policies are widely used by retailers to sell perishable food. Consumers purchase food at different prices during different sales periods. Some consumers may compare their experience with others who purchase the same items. Price unfairness or inequity is perceived when different prices are quoted without reasonable explanations. This study develops an optimal markdown model for perishable food pricing to optimise the food retailer revenue and enable a maximum aggregated consumer utility considering individuals’ price fairness perception. The model serves as the first step in evaluating trade-offs between food retailer revenue and consumer utility. In addition, it enables consumer utility to be depicted through perceived price fairness by including the effects of food perishability and scarcity. Another innovative feature is the equalisation of the consumer average aggregated utility during different sales periods as a condition of intertemporal price fairness perception. The proposed model is compared with two benchmark models to justify the effectiveness and advantages in the example. Finally, a sensitive analysis based on the food deterioration rate, consumer food desire rate and consumer average reservation price is conducted to justify the manner in which these factors influence the optimal pricing policy, and managerial insights are suggested for food retailers. 相似文献
80.