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

Sojourn Time Stabilization in Single-Server Processor Sharing Queues with Slowly Time-Varying Arrival Rates

We study the GI(t)/GI(t)/1/PS queue with the service rate subject to control. We consider a time-varying arrival rate that is slowly changing over time relative to the service requirement, where the pointwise stationary approximation (PSA) is known to be appropriate. Recent studies showed that the PSA-based square-root control stabilizes the mean waiting time (excluding service time) in the GI(t)/GI(t)/1 queue when the arrival rate is slowly varying. As the waiting time in the processor-sharing queue is trivially zero, we turned our attention to sojourn time (waiting time + service time) that is practically more important in the ICT service systems, such as data centers, where the PS discipline is favorable. Based on the PSA assumption and heavy-traffic approximation, we derive a simple service rate control for stabilizing the sojourn time in the GI(t)/GI(t)/1/PS queue. Simulation studies show reasonable stabilization in the heavy-traffic condition, whereas some unexpected but interesting results appear in the light-traffic situation.1