Impact of precipitation trends and the North Atlantic Oscillation on phreatic water levels in Low Belgium

A set of 10 representative multi-decade long time series of piezometric levels of phreatic aquifers were selected in different parts of Low Belgium to investigate correlations between groundwater levels, precipitation rates and the North Atlantic Oscillation (NAO) index. Correlations between piezometric levels and precipitation rates are always high and significant at the 5% level for all series. A direct relation between groundwater levels and the NAO is only possible if there is a correlation with aquifer recharge, which in north Belgium is limited to the winter period. Correlation between monthly precipitation and monthly NAO indices are highly temporal, with two distinct periods during which the correlation is significant at the 5% level. In summer (July and August) there is a negative correlation, in winter time (December and January) a positive one. As in summer aquifer recharge is negligible, only the winter NAO index can have an impact on groundwater levels. Of the ten investigated series, only two have a significant correlation at the 5% level, between piezometric levels and the December-January NAO values. Both wells lie in the same region, in the upper part of the lithologically heterogeneous Campine Complex. The local hydrogeological conditions here seem to increase sensitivity to winter NAO modus

Intelligent urban water infrastructure management

Copyright © 2013 Indian Institute of ScienceUrban population growth together with other pressures, such as climate change, create enormous challenges to provision of urban infrastructure services, including gas, electricity, transport, water, etc. Smartgrid technology is viewed as the way forward to ensure that infrastructure networks are fl exible, accessible, reliable and economical. “Intelligent water networks” take advantage of the latest information and communication technologies to gather and act on information to minimise waste and deliver more sustainable water services. The effective management of water distribution, urban drainage and sewerage infrastructure is likely to require increasingly sophisticated computational techniques to keep pace with the level of data that is collected from measurement instruments in the field. This paper describes two examples of intelligent systems developed to utilise this increasingly available real-time sensed information in the urban water environment. The first deals with the failure-management decision-support system for water distribution networks, NEPTUNE, that takes advantage of intelligent computational methods and tools applied to near real-time logger data providing pressures, flows and tank levels at selected points throughout the system. The second, called RAPIDS, deals with urban drainage systems and the utilisation of rainfall data to predict flooding of urban areas in near real-time. The two systems have the potential to provide early warning and scenario testing for decision makers within reasonable time, this being a key requirement of such systems. Computational methods that require hours or days to run will not be able to keep pace with fast-changing situations such as pipe bursts or manhole flooding and thus the systems developed are able to react in close to real time.Engineering and Physical Sciences Research CouncilUK Water Industry ResearchYorkshire Wate

Climate Change and Sea Level Rise Projections for Boston

While the broad outlines of how climate change would impact Boston have been known for some time, it is only recently that we have developed a more definitive understanding of what lies ahead. That understanding was advanced considerably with the publication of Climate Change and Sea Level Rise Projections for Boston by the Boston Research Advisory Group (BRAG).The BRAG report is the first major product of "Climate Ready Boston," a project led by the City of Boston in partnership with the Green Ribbon Commission and funded in part by the Barr Foundation. The BRAG team includes 20 leading experts from the region's major universities on subjects ranging from sea level rise to temperature extremes. University of Massachusetts Boston professors Ellen Douglas and Paul Kirshen headed the research.The BRAG report validates earlier studies, concluding Boston will get hotter, wetter, and saltier in the decades ahead (see figures below). But the group has produced a much more definitive set of projections than existed previously, especially for the problem of sea level rise. BRAG also concluded that some of the effects of climate change will come sooner than expected, accelerating the urgency of planning and action

The use of Lanczos's method to solve the large generalized symmetric definite eigenvalue problem

The generalized eigenvalue problem, Kx = Lambda Mx, is of significant practical importance, especially in structural enginering where it arises as the vibration and buckling problem. A new algorithm, LANZ, based on Lanczos's method is developed. LANZ uses a technique called dynamic shifting to improve the efficiency and reliability of the Lanczos algorithm. A new algorithm for solving the tridiagonal matrices that arise when using Lanczos's method is described. A modification of Parlett and Scott's selective orthogonalization algorithm is proposed. Results from an implementation of LANZ on a Convex C-220 show it to be superior to a subspace iteration code

Biobehavioral Correlates in Fibromyalgia

Introduction: Fibromyalgia (FMS) is a chronic pain syndrome characterized by non-restorative sleep, and fatigue. Over 75% of individuals with FMS complain of poor sleep quality and fatigue. These have been ranked by patients with FMS as having great impact on quality of life. A literature review suggested that poor sleep quality may be a predictor of increased stress and FMS symptom onset in those affected. However, no experimental studies have demonstrated a causal relationship between poor sleep and stress in people with FMS. Methods: Using a single stage cross-sectional design, the primary study aim was to compare 25 women with FMS and 25 women without FMS, on the following variables: autonomic nervous system activity; perceived stress; sleep quality; immune function (cytokines); and fatigue. The secondary aim was to explore the relationships among the above variables within each group. A third aim was to assess the validity of the Autonomic Symptoms Profile by comparing it to measures of heart rate variability and selected sleep indices. Significant Results: The FMS group had worse sleep quality, more autonomic symptoms, and greater fatigue than the non-FMS group; they also had higher TNF-α levels. The non-FMS group was more likely to have OSA. Non-FMS participants who had OSA also had higher IL-1β values than the FMS group. Study variables that correlated with each other in the FMS group differed from those seen in the non-FMS group, with the exception of the positive correlation of total arousals with AHI in both groups. In the FMS group, fatigue was positively correlated with perceived stress, autonomic symptoms, and TNF-α; stress was positively correlated with autonomic symptoms; and AHI was negatively correlated with IL-1β levels as well as the above noted correlation with total arousals. In the non-FMS group, sleep quality was positively correlated with fatigue, and sleep quality and fatigue were positively correlated with IL-1β. IL-1β also positively correlated with TNF-α. Total arousals were negatively correlated with mean RR interval. SDNN was correlated with RR interval and negatively correlated with AHI. The hypothesis tests related to construct validity of the ASP indicated no significant supportive correlations

Multiple criteria decision making in application layer networks

This work is concerned with the conduct of MCDM by intelligent agents trading commodities in ALNs. These agents consider trustworthiness in their course of negotiation and select offers with respect to product price and seller reputation. --Grid Computing