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The ultra-low-frequency (Hz region) elastic behaviour of SrTiO3 has been examined over a wide temperature range including the cubic-tetragonal transition at Tc = 105 K and the quantum paraelectric region (T < 40 K) using a three-point-bending method. A giant elastic softening has been found in the tetragonal phase. It is explained by a model, which takes into account the motion of ferroelastic domain walls in response to the applied dynamic stress. In the quantum paraelectric regime we have detected nonlinear elastic anomalies in the real and imaginary parts of the complex Young's modulus. Our data can be consistently described if we assume that ferroelectric order is induced by the applied strain gradient, which due to flexoelectric coupling is equivalent to a homogeneous electric field. Below 25 K the induced ordered polarization clusters are frozen on the experimental timescale (11 Hz).

This paper outlines the grand challenges in global sustainability research and the objectives of the FP7 Future Internet PPP program within the Digital Agenda for Europe. Large user communities are generating significant amounts of valuable environmental observations at local and regional scales using the devices and services of the Future Internet. These communities’ environmental observations represent a wealth of information which is currently hardly used or used only in isolation and therefore in need of integration with other information sources. Indeed, this very integration will lead to a paradigm shift from a mere Sensor Web to an Observation Web with semantically enriched content emanating from sensors, environmental simulations and citizens. The paper also describes the research challenges to realize the Observation Web and the associated environmental enablers for the Future Internet. Such an environmental enabler could for instance be an electronic sensing device, a web-service application, or even a social networking group affording or facilitating the capability of the Future Internet applications to consume, produce, and use environmental observations in cross-domain applications. The term “envirofied” Future Internet is coined to describe this overall target that forms a cornerstone of work in the Environmental Usage Area within the Future Internet PPP program. Relevant trends described in the paper are the usage of ubiquitous sensors (anywhere), the provision and generation of information by citizens, and the convergence of real and virtual realities to convey understanding of environmental observations. The paper addresses the technical challenges in the Environmental Usage Area and the need for designing multi-style service oriented architecture. Key topics are the mapping of requirements to capabilities, providing scalability and robustness with implementing context aware information retrieval. Another essential research topic is handling data fusion and model based computation, and the related propagation of information uncertainty. Approaches to security, standardization and harmonization, all essential for sustainable solutions, are summarized from the perspective of the Environmental Usage Area. The paper concludes with an overview of emerging, high impact applications in the environmental areas concerning land ecosystems (biodiversity), air quality (atmospheric conditions) and water ecosystems (marine asset management).

This paper investigates the usability of Future Internet technologies (aka “Generic Enablers of the Future Internet”) in the context of environmental applications. The paper incorporates the best aspects of the state-of-the-art in environmental informatics with geospatial solutions and scalable processing capabilities of Internet-based tools. It specifically targets the promotion of the “Environmental Observation Web” as an observation-centric paradigm for building the next generation of environmental applications. In the Environmental Observation Web, the great majority of data are considered as observations. These can be generated from sensors (hardware), numerical simulations (models), as well as by humans (human sensors). Independently from the observation provenance and application scope, data can be represented and processed in a standardised way in order to understand environmental processes and their interdependencies. The development of cross-domain applications is then leveraged by technologies such as Cloud Computing, Internet of Things, Big Data Processing and Analytics. For example, “the cloud” can satisfy the peak-performance needs of applications which may occasionally use large amounts of processing power at a fraction of the price of a dedicated server farm. The paper also addresses the need for Specific Enablers that connect mainstream Future Internet capabilities with sensor and geospatial technologies. Main categories of such Specific Enablers are described with an overall architectural approach for developing environmental applications and exemplar use cases

Recently, low-frequency measurements ͑0.1-Hz region͒ of the elastic susceptibility in KSCN near the orderdisorder phase transition at T c ϭ410 K revealed a relaxation that could be explained by entropy fluctuations. We present a phenomenological theory describing the heat-diffusion central peak in the macroscopic ͑qϭ0͒ dielectric susceptibility. It results from the Landau free energy and the heat-diffusion equation. The model predicts a relaxation in the ferroelectric phase at low frequencies that depends on sample size. It does not follow a simple Debye behavior, but reveals a long high-frequency tail. ͓S0163-1829͑96͒00822-3͔

We present the first low frequency (0.1 -20 Hz) measurements of the complex elastic constant on KSCN single crystals. Our measurements show very slow sample-size dependent elastic relaxations, at temperatures ranging from T, -40 K up to the order-disorder phase transition temperature T, . The data can be well explained with the assumption of temperature or equivalent entropy fluctuations. This phenomenon, although intimately related to the thermal-diffusion central peak phenomenon is, to our knowledge, for the first time seen in a macroscopic elastic susceptibility. PACS numbers: 64.60.Cn, 05.70.Ln, 44.30.+v, 62.20.Dc Potassium thiocyanate (KSCN) is a model crystal for studying order-disorder phase transitions [1]. A first

With the rise of social media platforms, crowdsourcing became a powerful tool for mobilizing the public. Events such as the earthquake in Haiti or the downfall of governments in Libya and Egypt indicate its potential in crisis situations. In the scope of this paper, we discuss the relevance of crowdsourcing in the area of crisis and disaster management (CDM). Starting with a general overview of the topic, we distinguish between different types of crowds and crowdsourcing and define what is meant by crowdtasking in the area of CDM. After considering technological, societal and ethical challenges for using crowdsourcing in crisis management, applications of crowdsourcing tools in ongoing projects are described and future developments outlined.