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This paper addresses the problem of electricity cost management for Internet service providers with a collection of spatially distributed data centers. As the demand on Internet services and cloud computing has kept increasing in recent years, the power usage associated with IDC operations has been uprising significantly. The cyber and physical aspects of IDCs interact with each other, and bring unprecedented challenges in power management. While most existing research focuses on reducing power consumptions of IDCs at one specific location, the problem of reducing the total electricity cost has been overlooked. This is an important problem faced by service providers, especially in the present multielectricity-market environment, where the price of electricity may exhibit temporal and spatial diversities. Further, for these service providers, guaranteeing the quality of service (QoS; i.e., service level objectives) such as service delay guarantees to the end users is of critical importance. This paper studies the problem of minimizing the total electricity cost geared to QoS constraint as well as the location diversity and time diversity of electricity price under multiregional electricity markets. We jointly consider both the cyber and physical management capabilities of IDCs, and exploit both the center-level load balancing and the server-level power control in a unified scheme. We model the problem as a constrained mixed integer programming based on generalized benders decomposition (GBD) technique. Extensive evaluations based on real-life electricity price data for multiple IDC locations demonstrate the effectiveness of our scheme. [ABSTRACT FROM PUBLISHER]

In this paper, we propose a new framework for the organization of the electric power industry, based on extensive use of information technology (IT) and on interactive decision making, where consumers and distributed producers join the traditional actors, utilities in particular, in making decisions. While many ideas considered in this paper have been put forward in recent years, such as the need to manage intermittency of renewable resources by means of proactive forecasting, and coordination with responsive demand and storage, we introduce a possible systematic IT-enabled mechanism necessary for the actual implementation of these technologies. We point out that in order to achieve a long-term sustainable energy utilization, it is essential to provide on-line information to internalize the value of just-in-time, just-in-place, and just-in-context distributed adaptation across the entire supply chain, ranging from the smallest consumers and energy providers, through their aggregators and system coordinators. We illustrate using our model-based novel simulator, how a carefully designed multidirectional and multitemporal information exchange could enable sustainable decision making while accounting for unique needs and capabilities of various resources and users. At the same time, information incentivizes the resources and users to contribute to system-wide sustainability objectives at value. We illustrate the dependence of such decisions-driven industry evolution on the industry rules (choice of performance objectives), as well as on the operating and planning practices for implementing the industry rules (temporal and spatial factors). Our model-based simulator could be used as a means of designing novel regulation defining rules, rights, and responsibilities regarding the type and rate of information to be exchanged in support of sustainable industry evolution. [ABSTRACT FROM PUBLISHER]

Presents a systematic framework for pricing transmission and ancillary services in competitive power markets. Framework for pricing transmission services; Cost-based pricing strategy; Ancillary services; Analysis of the proposed pricing approach; Numerical examples using the transmission line parameters; Conclusions.

The aim of this study is to investigate the chemical composition of ethanol, acetone extracts and essential oil of the roots and aerial parts of Sanguisorba minor subsp. muricata. Flavonoids and phenolic acids were identified as the main components in the studied extracts herein. Rutin and quercetin-3-sophoroside were found to be dominant flavonoids in both extracts. Although it was observed that the determined chemical compositions of the essential oil obtained from the aerial parts and roots of the plant species were quite different from the data obtained by Headspace measurement, as expected, the essential oils obtained from the species were found to be rich in mainly monoterpene hydrocarbons and oxygenated monoterpenes. While salicylaldehyde, carvacrol and linalool were determined as the main components in the essential oil obtained from the aerial parts of the species, the main components in the essential oil obtained from the roots were observed as borneol, myrtenol and a-campholenol. [ABSTRACT FROM AUTHOR]