Abstract
Time series of daily mean temperature obtained from the European Climate Assessment data set is analyzed with respect to their extremal properties. A time-series clustering approach which combines Bayesian methodology, extreme value theory and classification techniques is adopted for the analysis of the regional variability of temperature extremes. The daily mean temperature records are clustered on the basis of their corresponding predictive distributions for 25-, 50- and 100-year return values. The results of the cluster analysis show a clear distinction between the highest altitude stations, for which the return values are lowest, and the remaining stations. Furthermore, a clear distinction is also found between the northernmost stations in Scandinavia and the stations in central and southern Europe. This spatial structure of the return period distributions for 25-, 50- and 100-years seems to be consistent with projected changes in the variability of temperature extremes over Europe pointing to a different behavior in central Europe than in northern Europe and the Mediterranean area, possibly related to the effect of soil moisture and land-atmosphere coupling.

Abstract
Key-value stores hold the unprecedented bulk of the data produced by applications such as social networks. Their scalability and availability requirements often outweigh sacrificing richer data and processing models, and even elementary data consistency. Moreover, existing key-value stores have only random or order based placement strategies. In this paper we exploit arbitrary data relations easily expressed by the application to foster data locality and improve the performance of complex queries common in social network read-intensive workloads. We present a novel data placement strategy, supporting dynamic tags, based on multidimensional locality-preserving mappings. We compare our data placement strategy with the ones used in existing key-value stores under the workload of a typical social network application and show that the proposed correlation-aware data placement strategy offers a major improvement on the system's overall response time and network requirements.

Abstract
The underground movement of water through soil and rock is an important phenomenon in Civil Engineering. Its study is made more appealing to students if small scale prototypes are used, where several layouts of soil and water in steady state/transient conditions can be studied in detail. A water tank prototype was built with a reflective optical fibre pressure sensor based on a GRIN lens and a mirror. The mirror is connected to an elastic membrane that is deformed when water pressure is applied and the lens is correctly aligned with the mirror and fixed. The distance between the mirror and the lens changes, so the reflective optical power changes as well and it is directly proportional to the water pressure inside the tank. The results obtained for water pressure up to 4 kPa for filling and emptying operations show that the sensor has a linear response for pressure changes between 1.7 kPa and 3.4 kPa with a slope of 181 mu W/kPa for filling and 191 mu W/kPa for emptying. It is also observed some hysteresis that may possibly be reduced by choosing another material for the membrane. Using this type of sensor head it is possible to monitor different pressure points in the small scale prototype using the standard OTDR (Optical Time Domain Reflectometer) equipment.

Abstract
Recent trends in distributed embedded systems have shown an increase in the amount and heterogeneity of the information that needs to be exchanged, together with a growing importance of supporting dynamic reconfiguration and adaptive behaviors. In this paper we focus on Ethernet technology and we address the case of middle-size networking infrastructure with a few switches. We use the FTT-SE protocol to support dynamic heterogeneous real-time transactions with temporal isolation and we propose the needed scheduling adaptations to support multi-hop network configurations. The paper also includes a companion worst-case response-time analysis that allows verifying the timeliness of the system. Copyright 2011 ACM.

Abstract
Radon has continuously been monitored at the Roman spring of Tiberias, Israel since 2000 in the frame of an earthquake research project. However, there was no apparent earthquake related radon anomaly in 5 years of monitoring. Physical mechanisms behind periodic as well as transient radon variations were investigated. The radon signal contained periodic daily and non-periodic multi-day variations as well as seasonal patterns with maxima during winter. Spectral analysis showed diurnal and semidiurnal periodic constituents while tidal effects were absent. In 2003 the long-term average radon concentration dropped by 35%. Coevally, the diurnal and semi-diurnal radon variability considerably decreased. In contrast, the intensity of large-scale signals, corresponding to multi-day radon variability, increased. At this stage the level of the Kinneret Lake is suspected to be the driving force for the radon drop. Until 2003 the lake level hovered around 214 m below sea-level. In spring 2003 the lake level had risen by 4 m. The distance between the monitoring station and the lake shore is about 50 m. The radon concentration inversely followed the lake level with a time delay of about 3 months. Radon measured at a natural hot spring should depend on the flow rate of the hot water rising on the border faults of the pull-apart basin. Increased flow means less time for radon to decay and thus a positive correlation between the flow rate and the radon concentration is expected. Flow velocity is controlled by (i) the pressure at depth, and (ii) the fracture width. Both are affected by the loading forces of the graben filling to which the water column of the lake contributes. Due to the lack of data about the mass flow rates from the spring, a direct link between the flow rate and the radon concentrations cannot be proven. In fact, the hot water discharge seemed to be very stable in time. So, either minor changes of the flow rate affect the radon concentration or another mechanism is needed to explain the observations, e.g., the pressure-dependent gas solubility or the pressure-dependent mixing of different groundwater components. Nevertheless, this does not explain the appearance of long-periodic, intra-seasonal radon signals (with periods in the order of I month) which were practically absent before 2003. Such long-periodic radon signals were not reported till today.

Abstract
Purpose: This descriptive paper seeks to explore the role of Portuguese academics within corporate social responsibility and disclosure (CSR&D) research. It aims to give some insight into the nature and the extent of research on CSR&D being undertaken by Portuguese authors. Design/methodology/approach - This review specifically targeted international journals to see how much Portuguese research had penetrated the international business, management and accounting (BMA) academic discourse. The research that is reported in this paper is based on an electronic search of the online databases which include journals in these areas. The paper reviews journal articles published in BMA journals over the period 1998 to 2008. Findings: The paper reaches several conclusions: the volume of published research in international journals is still very low; most papers focus on CSR; research is overwhelmingly empirical in orientation; and most papers focus on Portugal. Hence, there is great scope for expanding the amount of research on CSR&D in Portugal, as well as improving the diversity of its content and its geographical coverage. Research limitations/implications : The paper is not expected to be a complete study, but rather a stimulus for future research. It is intended to provide a basis for comparison with further studies on CSR&D research in Portugal with studies from other geographical areas. Originality/value: The paper provides the first survey on CSR&D research in Portugal. It also provides the first opportunity to reflect on the current state of these still emerging academic fields. © Emerald Group Publishing Limited.