412 research outputs found

    A Risk-Adverse Approach for Reservoir Management with Application to Lake Como

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    A deterministic approach which avoids extreme failures in the management of a multipurpose reservoir is presented and discussed in the paper. The main feature of the method is to suggest a whole range of possible decisions which guarantee the efficient performance of the system. This allows the manager to choose the release which better fits with the additional informations or forecasts he might have, as well as to accommodate for secondary objectives which were not considered in the formulation of the problem. The results of the application of this approach to the management of Lake Como (Northern Italy) favorably compare with those obtained by a more traditional stochastic optimal control formulation and with the historical data

    Helicobacter pylori Eradication Therapy: Current Availabilities.

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    Background. Though Helicobacter pylori (HP) infections have progressively declined throughout most of the industrialized countries, a gradual increase in failure of HP eradication treatments is observed. Aim. To critically review evidence on the efficacy of the therapeutic availabilities for HP eradication, as yet. Methods. A selection of Clinical Trials, Systematic Reviews and Meta-analyses within the time period 2010-2012, was performed through a Medline search. Previous references were included when basically supporting the first selection. Results. An increasing rise in HP resistance rates for antimicrobial agents is currently observed. Further causes of HP treatment failure include polymorphisms of the CYP 2C19, an increased body mass index (BMI), smoking, poor compliance and re-infections. Alternative recent approaches to standard triple therapy have been attempted to increase the eradication rate, including bismuth-containing quadruple therapy, non-bismuth containing quadruple therapy, sequential therapy and levofloxacin-containing regimens. Conclusions. The main current aims should be the maintenance of a high eradication rate (>85%) of HP and the prevention of any increase in antimicrobial resistance. In the next future, the perspective of a tailored therapy could optimize eradication regimens within the different countries

    The Value of Information in Reservoir Management

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    This paper analyzes in quantitative terms the effectiveness of information in real-time operation of multipurpose reservoirs. For this, a simple and heuristic method strongly based on the experience of the manager is proposed and tested on the case of Lake Como (northern Italy). Particular attention is devoted to the possibility of evaluating the surplus of benefit due to the information available in real-time in addition to reservoir storage (e.g., snow cover, aquifer depth, and rainfall in the catchment). Moreover, a management scheme based on the direct use of the raw data is compared with a more sophisticated scheme using inflow predictors. Surprisingly, the first scheme, although more simple, performs better, thus justifying to a certain extent the little interest that practitioners sometimes seem to have for real-time forecasting techniques

    The Management of Lake Como

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    This paper presents a new and heuristic approach for improving the performance of multipurpose reservoirs already in operation. The main characteristic of the method is that the analyst must first learn from the past experience of the manager and synthesize it into a very simple operating rule. Then, the analyst must point out with the help of the manager what the acceptable modifications of such a rule are. Only after these phases have been carried out can possible improvements in the management be obtained by using standard optimization techniques. The method has been applied to the case of Lake Como, (Northern Italy), and the results are quite satisfactory since the major objectives of the management can be substantially improved. The average duration of the floods on the lake shores and the mean volume of the water deficits in the downstream agricultural areas are about halved, without lowering the mean yearly electricity production of the downstream run-of-river plants. Moreover, the advantages of a revision of the active storage and of a possible protection of the shores of the town of Como are also investigated. All the results of this study had a direct impact on the management of the lake. In fact, the proposed operating rule has been programmed on a microcomputer, which is now used every day by the manager as an essential support for his final decision; the active storage was lowered in June 1982 by the Ministry of Public Works, and the sunken part of Como town will be soon repaved and elevated by the Municipality

    The cost of inaction in air pollution abatement policies

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    Two alternative air quality policies are compared: one is the application of only mandatory abatement measures from 2020 to 2030. The second is the definition of a more active and locally-based policy that will lead to a better air quality at the end of the decade. Using an integrated modelling system, we demonstrate that the active policy is quite more convenient from the economic viewpoint, at least for the specific situation of the Lombardy region, considered in the study. Improving particulate matter concentrations may however produce worse ozone values. A full view of all pollutants is thus necessary when planning for air quality at regional level.Copyright (c) 2022 The Authors. This is an open access article under the CC BY-NC-ND license(https://creativecommons.org/licenses/by-nc-nd/4.0/

    Supply-Demand Price Coordination in Water Resources Management

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    A scheme is proposed for the coordination by prices of water supplies and demands in a region. The objective is to maximize the total regional net benefit from water use and it is achieved when the marginal benefit at each demand point is equal to the marginal cost of delivering water to that point. The class of problems to which the scheme can be applied is determined from the graph of the network connecting supplies and demands. An example is presented in which the scheme is applied to analyze possible interbasin water transfers in the Northwest Water Plan in Mexico

    Neural Structures to Predict River Stages in Heavily Urbanized Catchments

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    Accurate flow forecasting may support responsible institutions in managing river systems and limiting damages due to high water levels. Machine-learning models are known to describe many nonlinear hydrological phenomena, but up to now, they have mainly provided a single future value with a fixed information structure. This study trains and tests multi-step deep neural networks with different inputs to forecast the water stage of two sub-alpine urbanized catchments. They prove effective for one hour ahead flood stage values and occurrences. Convolutional neural networks (CNNs) perform better when only past information on the water stage is used. Long short-term memory nets (LSTMs) are more suited to exploit the data coming from the rain gauges. Predicting a set of water stages over the following hour rather than just a single future value may help concerned agencies take the most urgent actions. The paper also shows that the architecture developed for one catchment can be adapted to similar ones maintaining high accuracy

    The cost of inaction in air pollution abatement policies

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    Two alternative air quality policies are compared: one is the application of only mandatory abatement measures from 2020 to 2030. The second is the definition of a more active and locally-based policy that will lead to a better air quality at the end of the decade. Using an integrated modelling system, we demonstrate that the active policy is quite more convenient from the economic viewpoint, at least for the specific situation of the Lombardy region, considered in the study. Improving particulate matter concentrations may however produce worse ozone values. A full view of all pollutants is thus necessary when planning for air quality at regional level.Copyright (c) 2022 The Authors. This is an open access article under the CC BY-NC-ND license(https://creativecommons.org/licenses/by-nc-nd/4.0/

    Planning Complex Agro-Ecosystems: The Case of Analog Forestry

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    Traditional agroecosystems, aimed at maximizing the short term productivity, are characterized by oversimplification of ecological structure and dependence on the use of external inputs. Moreover, intensive agriculture is one of the main cause of deforestation. The main consequence of traditional agriculture is the loss of natural ecosystems and of their precious services. Analog forestry has emerged as a sustainable productive model able to be integrated in forest contexts, without degrading their ecological functions. The obtained agro-ecosystem is characterized by an ecological structure similar to the one of forest, and by the presence of several productive species in the same area. In this study we formalize a planning problem aimed at the optimized design of an analog forest on the medium term. In particular, besides the maximization of income, we considered both ecological (i.e., the presence of different vertical layers and several species) and socio-economic requirements (i.e., the smoothing of both inter- and intra-annual variability of income). We focus the analysis on the Peruvian Amazon, basing on a species database created by ArBio, a Peruvian association which promotes the analog forestry as tool for pursuing the conservation of forest ecosystem services. The obtained results show that the interannual income variability, characterizing an approach of short-term maximization, can be eliminated by adopting the gradual planting of individuals belonging to the same species. Secondly, we quantified the economic and ecological performance of the designed analog forest under different settings of the planning problem. The introduction of the defined ecological and socio-economic constraints affects the economic performance on the medium term, by reducing the annual economic income up to 80%

    Assessing the Economic Value of a Regional Air Quality Plan

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    When developing an air quality plan, environmental authorities usually devise a number of individual actions, constituted by the application of both technical (end-of-pipe) and energy efficiency measures. They may range from the incentives to buy less polluting vehicles, to the enforcement of stricter rules on domestic heating. The assessment of the economic effectiveness for the society as a whole of the individual measures and of the overall plan requires a flexible support system able to quickly perform air quality impact evaluations on the specific area. One such system is RIAT+, a software package developed and tested during a series of European research projects, which has been used to evaluate costs and benefits of the Lombardy Region Air Quality Plan (PRIA), constituted by about 90 different actions to be implemented within 2020. The adoption of each measure means a certain change in the emission, which is distributed over the regional territory in different way, depending on the type of measure. A shift of the car fleet to a different EURO class, for instance, means an emission reduction only on the road network, while a reduced use of electricity may imply a lower emission of power plants at specific sites. To evaluate the effects of these emission changes, RIAT+ adopts a surrogate model approach, namely using a neural network calibrated on few results of a full chemical transport model. It is thus possible to rapidly evaluate the improvements in the population exposure and health and the consequent reduction of external costs. The final economic assessment is obtained by comparing the sum of energy savings and external cost reductions with the implementation costs of the corresponding measures
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