Abstract-Data center management (DCM) is increasingly becoming a significant challenge for enterprises hosting large scale online and cloud services. Machines need to be monitored, and the scale of operations mandates an automated management with high reliability and real-time performance. Existing wired networking solutions for DCM come with high cost. In this paper, we propose a wireless sensor network as a cost-effective networking solution for DCM while satisfying the reliability and latency performance requirements of DCM. We have developed CapNet, a real-time wireless sensor network for power capping, a time-critical DCM function for power management in a cluster of servers. CapNet employs an efficient event-driven protocol that triggers data collection only upon the detection of a potential power capping event. We deploy and evaluate CapNet in a data center. Using server power traces, our experimental results on a cluster of 480 servers inside the data center show that CapNet can meet the real-time requirements of power capping. CapNet demonstrates the feasibility and efficacy of wireless sensor networks for time-critical DCM applications.

China's urbanization in the post‐reform period since 1978 is especially notable for three features: large scale, fast speed, and long process. And it is now facing challenges in land, energy, water resources, and environment. All these challenges are linked to the emissions of carbon dioxide. As China is expected to have a cap on emissions, there must be a limit to emissions over the process of urbanization in China. In this article, a comprehensive analysis is implemented aimed at budgeting carbon for China's urbanization from 2020 to 2040. By incorporating the concept and principle of ecological civilization into China's urbanization, the constraint on carbon budget not only increases the market demand for raw materials, labor, and commodities that act as the main driving forces for economic growth, but also guarantees the state energy safety and contributes to the global ecological security. WIREs Energy Environ 2015, 4:406–409. doi: 10.1002/wene.153 This article is categorized under: Energy and Climate > Climate and Environment Energy Policy and Planning > Climate and Environment

Recent increases in urbanization and tourism threaten the viability of UNESCO world heritage sites across the globe. The Angkor world heritage site located in southern Cambodia is now facing such a challenge. Over the past two decades, Angkor has seen over 300,000% growth in international tourist arrivals, which has led to uncontrolled development of the nearby city of Siem Reap. This study uses remote sensing and GIS to comprehend the process of urban expansion during the past 14 years, and has applied the CA-Markov model to predict future urban expansion. This paper analyzes the urban pressure on the Angkor site at different scales. The results reveal that the urban area of Siem Reap city increased from 28.23 km2 in 2004 to 73.56 km2 in 2017, an increase of 160%. Urban growth mainly represented a transit-oriented pattern of expansion, and it was also observed that land surfaces, such as arable land, forests, and grasslands, were transformed into urban residential land. The total constructed land area in the core and buffer zones increased by 12.99 km2 from 2004 to 2017, and 72% of the total increase was in the buffer zone. It is predicted that the built-up area in Siem Reap is expected to cover 135.09 km2 by 2025 and 159.14 km2 by 2030. The number of monuments that are most likely be affected by urban expansion is expected to increase from 9 in 2017 to 14 in 2025 and 17 in 2030. The urban area in Siem Reap has increased dramatically over the past decade and monuments continue to be decimated by urban expansion. This paper urges closer attention and urgent actions to minimize the urban pressure on the Angkor site in the future.

Gel-forming fibers (GF fibers) can serve as nucleation sites to prepare calcium carbonate (CaCO(3)) because they can adsorb large amounts of Ca(2+) due to their porous structure. In this paper, mineralization behavior of CaCO(3) on GF fibers in ethanol-water mixed solvents without any additives has been investigated. The results showed that some crystals covered the fibers, while others were embedded in fibers. Twin-sphere based vaterite, zonary and rodlike calcite with large aspect ratio could be prepared successfully. The effect of ethanol content inside GF fibers, concentration of Ca(2+) and CO(3)(2-), mineralization time, miscibility between alcohol and water, and temperature were studied. Lastly, a possible mineralization mode was suggested. This work could provide a new method to prepare inorganic/polymer hybrid materials. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, WeinheimNational Natural Science Foundation of China[50873082, 50903067]; Scientific and Technical Project of Fujian Province of China[2009J1009, 2010H6021, 2010J01306]; Special Program for Key Research of Chinese National Basic Research Program[2011CB612303]; Science and Technology Project of Zhejiang Province of China[2009C31084