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961.
编译器性能是计算机系统架构充分发挥优势的体现, 编译器优化受机器平台与编译器特征的影响.编译器分析是在目标编译器与多参照编译器、目标平台与多参照平台之间进行的, 即编译器与平台的组合是分析的基础.只有在多组合情况下才能为目标编译器优化提供最大可能的性能提升空间和详细的优化方案, 但增加编译器与平台的组合往往会增加无法计量的分析工作量.为此, 提出了一种基于峰值架构的面向跨平台跨编译器分析方法.基于峰值架构集为目标编译器构建理想性能空间, 结合细粒度优势优化定位技术为目标编译器提供优势优化选项和优化方向, 并实现编译器优化.最后通过实验验证了该分析技术的实用性与普适性, 并为Intel平台上的目标编译器gcc提供了优化方向. 相似文献
962.
今天,活跃在国际建筑舞台上的建筑师是 50来岁的一代人,与现代主义建筑大师们相比较,这一代建筑师具有更为特殊的位置。因为他们知道如何糅合不同的建筑创作模式,创造出体现设计者独立个性的做法,善于处理历史文化与当前现实的关系,适宜的合作规模和在建筑作品中巧妙地不事张扬。可是,意大利50来岁的建筑师却不知道处理这样一种恰如其分的平衡,例如如何体现设计者建筑语言的肯定性、在合作过程中如何认识自身的位置,以及面对当今复杂的施工要求如何保证建筑作品在实施过程中不失去个性,正是因为这些问题的处理不当,致使在国际建筑舞台上缺少他们的身影。今天,可以肯定的倒是30-40来岁的意大利建筑师,阿克雅建筑师事务所就是其中的一员。他们能够娴熟地运用国际流行的建筑语言,并且不局限在某种作者定式和个人魅力,致力于把纯粹的学术研究与建筑实践结合在一起。这一代意大利建筑师表现出来的特点是把每一次设计作为一次积极展示他们个人特点的机会,表现出强烈的希望设计作品付诸实施的愿望,以及作品中展现出扎实的结构专业能力。 相似文献
963.
The flexible and pay-as-you-go computing capabilities offered by Cloud infrastructures are nowadays very attractive, and widely adopted by many organizations and enterprises. In particular this is true for those having periodical or variable tasks to execute, and, choose to not or cannot afford the expenses of buying and managing computing facilities or software packages, that should remain underutilized for most of the time. For their ability to couple the scalability offered by public service providers, with the wider Quality of Service (QoS) provisions and ad-hoc customizations provided by private Clouds, Hybrid Clouds (HC) seem a particularly appealing solution for customers requiring something more than the mere availability of the service.The paper firstly introduces a Cloud brokering system leveraging on a promising architectural approach, based on the use of a gateway toolkit. This approach provides noticeably advantages, both to customers and to Cloud Brokers (CB), for its ability to hide all the intricacies related to the management of powerful, but often complex and heterogeneous infrastructures like the Cloud. Moreover such approach, through customized interfaces, facilitates customers in accessing Cloud resources thus easing the tailored deployment and execution of their applications and workflows.The major contribution of this work is given by the analysis of a set of brokering strategies for Hybrid Clouds, implemented by a brokering algorithm, aimed at the execution of various applications subject to different user requirements and computational conditions. With the objective of firstly maximize both user satisfaction and CB’s revenues the algorithm also pursues profit increases through the reduction of energy costs by adopting energy saving mechanisms. A simulation model is used to evaluate performance, and the results show that differences among strategies depend on type and size of system loads and that the use of turn on and off techniques greatly improves energy savings at low and medium load rates thus indirectly increasing CB revenues without diminishing customers’ satisfaction. 相似文献
964.
The main limits on adaptive Volterra filters are their computational complexity in practical implementation and significant performance degradation under the impulsive noise environment. In this paper, a low-complexity pipelined robust M-estimate second-order Volterra (PRMSOV) filter is proposed to reduce the computational burdens of the Volterra filter and enhance the robustness against impulsive noise. The PRMSOV filter consists of a number of extended second-order Volterra (SOV) modules without feedback input cascaded in a chained form. To apply to the modular architecture, the modified normalized least mean M-estimate (NLMM) algorithms are derived to suppress the effect of impulsive noise on the nonlinear and linear combiner subsections, respectively. Since the SOV-NLMM modules in the PRMSOV can operate simultaneously in a pipelined parallelism fashion, they can give a significant improvement of computational efficiency and robustness against impulsive noise. The stability and convergence on nonlinear and linear combiner subsections are also analyzed with the contaminated Gaussian (CG) noise model. Simulations on nonlinear system identification and speech prediction show the proposed PRMSOV filter has better performance than the conventional SOV filter and joint process pipelined SOV (JPPSOV) filter under impulsive noise environment. The initial convergence, steady-state error, robustness and computational complexity are also better than the SOV and JPPSOV filters. 相似文献
965.
维斯宁兄弟是苏联"构成主义"建筑运动的旗手。1922年,兄弟三人联手,支持先锋的艺术观念,并且独创出一种现代建筑流派。1933年,列奥尼德·维斯宁逝世。此后,维克多依然保持了成功的职业生涯。而亚历山大渐渐退出了公开的职业活动。 相似文献
966.
Over the last two decades, software product lines have been used successfully in industry for building families of systems of related products, maximizing reuse, and exploiting their variable and configurable options. In a changing world, modern software demands more and more adaptive features, many of them performed dynamically, and the requirements on the software architecture to support adaptation capabilities of systems are increasing in importance. Today, many embedded system families and application domains such as ecosystems, service-based applications, and self-adaptive systems demand runtime capabilities for flexible adaptation, reconfiguration, and post-deployment activities. However, as traditional software product line architectures fail to provide mechanisms for runtime adaptation and behavior of products, there is a shift toward designing more dynamic software architectures and building more adaptable software able to handle autonomous decision-making, according to varying conditions. Recent development approaches such as Dynamic Software Product Lines (DSPLs) attempt to face the challenges of the dynamic conditions of such systems but the state of these solution architectures is still immature. In order to provide a more comprehensive treatment of DSPL models and their solution architectures, in this research work we provide an overview of the state of the art and current techniques that, partially, attempt to face the many challenges of runtime variability mechanisms in the context of Dynamic Software Product Lines. We also provide an integrated view of the challenges and solutions that are necessary to support runtime variability mechanisms in DSPL models and software architectures. 相似文献
967.
基于地域乡土观念的金梅湖乡村文化活动中心建筑规划设计 总被引:1,自引:0,他引:1
基于乡土观念的现象与特点,探讨了在城市化进程中乡村文化活动空间设计的定位、原则及方法,以金梅湖乡村文化活动中心建筑设计为例,其设计遵从表达乡村文化地域特色与提升乡村生活品质并重的思路,以期带给乡村经济、社会以及环境的平衡、健康发展。 相似文献
968.
969.
970.
循证设计作为一种新型设计手段,主要是充分利用已有的研究成果及知识来提升设计品质。将循证设计理论应用到医疗建筑设计中,能有效帮助患者康复。本文在分析循证设计内涵的基础上,重点探讨了其在医疗建筑设计中的应用。 相似文献