Importance of the Doppler Effect to the Determination of the Deuteron Binding Energy

The deuteron binding energy extracted from the reaction ${}^1H(n,\gamma){}^2H$ is reviewed with the exact relativistic formula, where the initial kinetic energy and the Doppler effect are taken into account. We find that the negligible initial kinetic energy of the neutron could cause a significant uncertainty which is beyond the errors available up to now. Therefore, we suggest an experiment which should include the detailed informations about the initial kinetic energy and the detection angle. It could reduce discrepancies among the recently reported values about the deuteron binding energy and pin down the uncertainty due to the Doppler broadening of $\gamma$ ray.Comment: 5 page

A Distributed Server Provisioning Algorithm for Data Centers with Nonstationary User Requests

In the era of growing information communication technology, large-scale data centers are inevitable solutions for processing and storing huge amount of incoming data. Large-scale data centers, however, consume tremendous amount of energy. Achieving energy-efficiency is one of the key problems in data center operations. In the previous research study, we proposed a distributed speed scaling and load balancing algorithm for reducing energy consumption while attaining a desired quality of service when the user requests are stationary stochastic processes. In this research study, we seek how to extend the previous algorithm when the user requests are arriving in nonstationary fashion.1

Power- and QoS-Aware Job Assignment With Dynamic Speed Scaling for Cloud Data Center Computing

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Energy Efficiency of Data Center Operating Practices: Server Clustering, Powering On/Off, and Bang-Bang Control

Data centers today account for up to 3% of all global electricity consumption and produce 200 million metric tons of CO2. Hence, improving energy efficiency is an important operational concern. This article examines common operating practices such as server clustering, powering on/off, and bang–bang control in terms of energy efficiency. Extending the mixed integer programming (MIP) formulation in a previous research study, we introduce new constraints reflecting the operating practices adopted for operational convenience. We develop an algorithmic strategy for constructing energy efficient clusters of servers using two upper bounds on the cluster size. Numerical experiments show that server clustering and bang–bang control do not diminish energy efficiency, and that powering on/off by itself is insuffcient. Our results produce a conclusion that differs from the published literature on data center design and operations.11sciescopu