Online computation with advice

We consider a model for online computation in which the online algorithm receives, together with each request, some information regarding the future, referred to as advice. The advice is a function, defined by the online algorithm, of the whole request sequence. The advice provided to the online algorithm may allow an improvement in its performance, compared to the classical model of complete lack of information regarding the future. We are interested in the impact of such advice on the competitive ratio, and in particular, in the relation between the size b of the advice, measured in terms of bits of information per request, and the (improved) competitive ratio. Since b=0 corresponds to the classical online model, and b=⌈log∣A∣⌉, where A is the algorithm’s action space, corresponds to the optimal (offline) one, our model spans a spectrum of settings ranging from classical online algorithms to offline ones.In this paper we propose the above model and illustrate its applicability by considering two of the most extensively studied online problems, namely, metrical task systems (MTS) and the k-server problem. For MTS we establish tight (up to constant factors) upper and lower bounds on the competitive ratio of deterministic and randomized online algorithms with advice for any choice of 1≤b≤Θ(logn), where n is the number of states in the system: we prove that any randomized online algorithm for MTS has competitive ratio Ω(log(n)/b) and we present a deterministic online algorithm for MTS with competitive ratio O(log(n)/b). For the k-server problem we construct a deterministic online algorithm for general metric spaces with competitive ratio k^O(1/b) for any choice of Θ(1)≤b≤logk.     

加强能源法治研究助推低碳发展

本文运用马克思主义关于内因与外因辩证关系的理论,分析了我国能源与经济发展的成就和面临的严峻挑战,认为转变发展方式,实行低碳发展,是我国当今以煤为主又必须适应全球低碳发展趋势的两难选择中最现实的选择。实行低碳发展必然引起法律关系的变化,要求能源法律制度为之发挥强有力的保障和支撑作用。据此作者提出了进一步完善能源法律制度体系建设及需要侧重考虑的一些重要问题的建议。     

我国离心铸造球墨铸铁管发展探讨

简述了离心铸造球墨铸铁管生产及其工艺特点,简析了我国离心铸造球墨铸铁管的生产现状,提出了加速发展的建议和措施。     

ASP及其在基于Web的图书馆咨询系统中的应用

基于 Web的动态、交互式综合页面形式是图书馆咨询系统的发展方向 .通过对 ASP的结构、特点 ,以及 ASP交互访问 Web数据库方法的分析 ,提出了 ASP在基于 Web形式的图书馆咨询系统中的应用设计方案     

光网络网管系统瑕疵分析及建议

从网管系统的结构、通信协议和信息模型,以及开放性、安全性、可控性、可靠性和经济性等方面分析了当前光网络网管系统的瑕疵,提出了未来光网络建设建议。     

城市湿地公园植物景观营造技术探讨

该文以笔者对杭州西溪国家湿地公园的多年实地调研和分析为基础,从生态学、人性化、美学以及特色植物景观营造等角度对城市湿地公园的植物景观营造技术进行了探讨,并就城市湿地公园植物景观营造的更好开展提出了一些建议,最后列举了今后研究和实践中需要进一步深入的若干问题。     

改进我国国债发行的几点建议

本文从我国国债市场的发展历程出发,总结了我国国债市场的现状及存在的不足:国债供不应求等六点。又从进一步发展的角度提出了改进和完善国债管理及建立市场经济下的管理机制的几点建议:保持国债发行的适度规模等五点。     

乙酸乙酯的市场需求与生产方法

介绍了乙酸乙酯的制备方法及应用,讨论和分析了现有工艺技术的特点及发展现状,并提出了相关建议。     

桑椹食品的开发探讨

该文重点介绍了桑椹的营养成分和生理功能,并就桑椹食品的研究意义和生产现状进行了阐述,最后就桑椹食品的开发策略提出了几点建议。