79,745 research outputs found

    Rationalising territorially dispersed consumption: the projects of Fernand Courtoy for the electricity production and distribution of Belgium

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    The electrification of the notoriously dispersed urbanization patterns of Belgium was a complex and confused operation. The superposition of a nationwide industrial framework, consisting of large elements such as coal basins and sea ports, and a territory characterized by a very fragmented and functionally diverse spatial structure, led to the appearance of electricity in all sorts of locations following diverse arrangements. Within fifty years, large-scale industrial self-producers, regional electricity companies, provincial projects, urban municipal companies and small-scale local initiatives brought electricity to every part of Belgium, barely guided by a national policy. Within this disordered context, Fernand Courtoy occupied a very particular and somewhat exceptional position. As electrical engineer and shareholder of a local electricity company he was able to rationalize the electricity supply, first within his company (1911), and soon after in the entire industrial city of Liege (1919). Later, he became the driving force behind the establishment of the association of industrial self-producers (1922) and founded a consultancy firm that developed electricity plans for private companies as well as strategies for the electrification of whole provinces. Moreover, Courtoy was able to put his mark on the 1927 governmental commission that investigated the organization of an efficient electricity supply on the national scale. As the report of this commission proved to be too controversial for the strongly divided electricity sector, few of its propositions were realized. Nonetheless, through the debate provoked by the commission and through the numerous projects undertaken by his firm, Courtoy was able to introduce a perspective which was rather unusual for the Belgian context, combining large-scale rationalization with the national economic policies of dispersion. The paper discusses the various ways in which his plans searched for an efficient electricity supply, while recognizing the generalized availability of electricity as a necessary condition for Belgium’s distributed model of industrialization

    Issues Related to Incorporating Northern Peatlands into Global Climate Models

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    Northern peatlands cover ~3–4 million km2 (~10% of the land north of 45°N) and contain ~200–400 Pg carbon (~10–20% of total global soil carbon), almost entirely as peat (organic soil). Recent developments in global climate models have included incorporation of the terrestrial carbon cycle and representation of several terrestrial ecosystem types and processes in their land surface modules. Peatlands share many general properties with upland, mineral-soil ecosystems, and general ecosystem carbon, water, and energy cycle functions (productivity, decomposition, water infiltration, evapotranspiration, runoff, latent, sensible, and ground heat fluxes). However, northern peatlands also have several unique characteristics that will require some rethinking or revising of land surface algorithms in global climate models. Here we review some of these characteristics, deep organic soils, a significant fraction of bryophyte vegetation, shallow water tables, spatial heterogeneity, anaerobic biogeochemistry, and disturbance regimes, in the context of incorporating them into global climate models. With the incorporation of peatlands, global climate models will be able to simulate the fate of northern peatland carbon under climate change, and estimate the magnitude and strength of any climate system feedbacks associated with the dynamics of this large carbon pool

    Modelling interdependencies between the electricity and information infrastructures

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    The aim of this paper is to provide qualitative models characterizing interdependencies related failures of two critical infrastructures: the electricity infrastructure and the associated information infrastructure. The interdependencies of these two infrastructures are increasing due to a growing connection of the power grid networks to the global information infrastructure, as a consequence of market deregulation and opening. These interdependencies increase the risk of failures. We focus on cascading, escalating and common-cause failures, which correspond to the main causes of failures due to interdependencies. We address failures in the electricity infrastructure, in combination with accidental failures in the information infrastructure, then we show briefly how malicious attacks in the information infrastructure can be addressed

    Deep ocean disposal of sewage sludge off Orange County, California: a research plan

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    Even though the discharge of sludge into the ocean via an outfall is not now permitted, this research plan has been prepared to show what could be learned with a full scale experimental sludge discharge of 150 dry tons/day by the County Sanitation Districts of Orange County into deep water (over 1000 feet). To provide a wide range of inputs and evaluation, a broad-based Research Planning Committee was established to advise the Environmental Quality Laboratory on the overall content and details of the research plan. Two meetings were held at EQL on: March 4-5, 1982: The entire Committee July 19-20, 1982: A working subgroup of the Committee The entire Committee is listed in Appendix B, with footnotes to indicate meeting attendance. Those unable to come to a meeting were asked to comment on the drafts by mail or telephone. We gratefully acknowledge the members of the Research Planning Committee for their generous help in formulating the research tasks and reviewing report drafts

    Fast human motion prediction for human-robot collaboration with wearable interfaces

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    In this paper, we aim at improving human motion prediction during human-robot collaboration in industrial facilities by exploiting contributions from both physical and physiological signals. Improved human-machine collaboration could prove useful in several areas, while it is crucial for interacting robots to understand human movement as soon as possible to avoid accidents and injuries. In this perspective, we propose a novel human-robot interface capable to anticipate the user intention while performing reaching movements on a working bench in order to plan the action of a collaborative robot. The proposed interface can find many applications in the Industry 4.0 framework, where autonomous and collaborative robots will be an essential part of innovative facilities. A motion intention prediction and a motion direction prediction levels have been developed to improve detection speed and accuracy. A Gaussian Mixture Model (GMM) has been trained with IMU and EMG data following an evidence accumulation approach to predict reaching direction. Novel dynamic stopping criteria have been proposed to flexibly adjust the trade-off between early anticipation and accuracy according to the application. The output of the two predictors has been used as external inputs to a Finite State Machine (FSM) to control the behaviour of a physical robot according to user's action or inaction. Results show that our system outperforms previous methods, achieving a real-time classification accuracy of 94.3±2.9%94.3\pm2.9\% after 160.0msec±80.0msec160.0msec\pm80.0msec from movement onset

    The influence of climate and hydrological variables on opposite anomaly in active-layer thickness between Eurasian and North American watersheds

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    This study not only examined the spatiotemporal variations of active-layer thickness (ALT) in permafrost regions during 1948-2006 over the terrestrial Arctic regions experiencing climate changes, but also identified the associated drivers based on observational data and a simulation conducted by a land surface model (CHANGE). The focus on the ALT extends previous studies that have emphasized ground temperatures in permafrost regions. The Ob, Yenisey, Lena, Yukon, and Mackenzie watersheds are foci of the study. Time series of ALT in Eurasian watersheds showed generally increasing trends, while the increase in ALT in North American watersheds was not significant. However, ALT in the North American watersheds has been negatively anomalous since 1990 when the Arctic air temperature entered into a warming phase. The warming temperatures were not simply expressed to increases in ALT. Since 1990 when the warming increased, the forcing of the ALT by the higher annual thawing index (ATI) in the Mackenzie and Yukon basins has been offset by the combined effects of less insulation caused by thinner snow depth and drier soil during summer. In contrast, the increasing ATI together with thicker snow depth and higher summer soil moisture in the Lena contributed to the increase in ALT. The results imply that the soil thermal and moisture regimes formed in the pre-thaw season(s) provide memory that manifests itself during the summer. The different ALT anomalies between Eurasian and North American watersheds highlight increased importance of the variability of hydrological variables
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