Demand monitoring equipment is installed in each factory or office, and is linked to the Mitsubishi Electric Head Office via the intranet, where a centralized monitoring server provides comprehensive control (Fig. 1). The multi-demand viewer uses its wide-area control function to collect electric power data from each site in real time, and sends out an alert e-mail when there is a high probabil...

A technique is described to dynamically limit power dissipation in heavily pipelined digital circuits. Stages in the pipeline are clock gated based upon validity of data at that stage. As the pipe approaches a stalled or inactive state, branches of the clock tree are progressively disabled stage by stage. The technique has the additional advantage of removing gaps or “bubbles” in the data strea...

This paper reviews existing power management techniques on wireless LAN and verifies the effects of different power management techniques applied to the case for VoIP over WiFi through experiments. Voice communication imposes timely constraints such as short time interval between packets and the need to be always listening for potential incoming connections. It also poses opportunities related ...

This paper presents a mechanism that improves the energy efficiency of PSM (Power Saving Mechanism) specified for DCF (Distributed Coordination Function) in IEEE 802.11. In PSM, time is divided into beacon intervals. At the start of each beacon interval, every node stays awake for a duration, called the ATIM Window. During the ATIM window, nodes exchange control packets to determine whether the...

Power consumption is rapidly increased in data centers because the number of data center is increased and more the scale of data center become larger. Therefore, it is one of key research items to reduce power consumption in data center. The peak power of a typical server is around 250 watts. When a server is idle, it continues to use around 60% of the power consumed when in use, though vendors...

To extend lifetime of battery-powered mobile device before its recharging in broadband wireless access networks, power saving mechanism in MAC (medium access control) has become a significant design issue. Basically, a power saving mechanism is manipulated by adjusting operating parameters such as the minimum sleep interval (Tmin) and the maximum sleep interval (Tmax). In this paper, we propose...

Studies of ad hoc wireless networks are rapidly gaining popularity due to its varied and innovative applications. Medium Access Control (MAC) protocols in such networks are responsible to coordinate access among active nodes. Wireless nodes are largely powered by batteries which restricts the quantity of energy available to the nodes. Routing for wireless nodes is incorporated with power saving...

Data Processing is an important issue in wireless sensor networks (WSNs). However, constrained energy will lead to the network life deeply affected by the power consumption of data processing. Hence, reducing the power consumption becomes an important objective to improve the performance of WSNs. In this paper, an energy-efficient data processing scheme (EED) is proposed to reach the goal of sa...

As processor power density increases, thermal and power control becomes critical for packet processing. Network applications feature ON/OFF execution pattern, which causes frequent temperature and power consumption changes in the processor. In this paper, we propose a novel power aware thermal management algorithm, which achieves power saving in multicore processors by employing a vacation sche...

We analyze the power saving operation called Discontinuous Reception (DRX) with a novel bursty packet arrival model in 3GPP Long Term Evolution (LTE)-Advanced networks. Typical analytical studies on the power saving operations in wireless networks have been carried out under the assumption that an expectation of exponentially distributed packet arrival intervals stays unchanged. However, practi...