BACKGROUND Between September 17 and October 3, 2009, hundreds of workers employed in a manufacturing factory in Shenzhen, a city in south China developed a sudden onset of acute gastroenteritis. A retrospective cohort study is designed to identify the risk factors and control this outbreak. METHODS Information on demographic characteristics, working place, the history of contact with a person...

in this study, a one-dimensional model called dyresm was used to simulate the thermal structure and artificial destratification of 15-khordad reservoir over a period of one year. the simulation showed that the reservoir is warm monomictic and is stratified during 210 days of the simulation year. the model reproduced the temperature of the meta- and hypolimnion very close to the observed data, b...

Satellite images are an effective tool for the detection of phytoplankton blooms, since they cause striking changes in water color. Bloom intensity can be expressed in terms of chlorophyll-a concentration. Previous studies suggest the use of Landsat TM4/TM3 reflectance ratio to retrieve surface chlorophyll-a concentration from aquatic systems. In this study we assumed that a remote sensing trop...

This paper describes the investigation of a single-well enhanced geothermal system comprised of a downhole thermosiphon and a novel completion design using a downhole heat exchanger. The thermosiphon is a device that takes advantage of the gravity head difference between liquid flowing down the annulus and vapor flowing up the tubing. Without a connection to a large reservoir volume, a downhole...

More than half of all hydrocarbon reservoirs are Naturally Fractured Reservoirs (NFRs), in which production forecasting is a complicated function of fluid flow in a fracture-matrix system. Modelling of fluid flow in NFRs is challenging due to formation heterogeneity and anisotropy. Stress sensitivity and depletion effect on already-complex reservoir permeability add to the sophistication. Horiz...

We present a forecast-based adaptive management framework for water supply reservoirs and evaluate the contribution of long-term inflow forecasts to reservoir operations. Our framework is developed for snow-dominated river basins that demonstrate large gaps in forecast skill between seasonal and inter-annual time horizons. We quantify and bound the contribution of seasonal and inter-annual fore...

Recurrent Neural Networks (RNNs) have been a prominent concept within artificial intelligence. They are inspired by Biological Neural Networks (BNNs) and provide an intuitive and abstract representation of how BNNs work. Derived from the more generic Artificial Neural Networks (ANNs), the recurrent ones are meant to be used for temporal tasks, such as speech recognition, because they are capabl...

Reservoir regulation and operational decision-making construct an extremely complex process, which shows the apparent semi-structured or unstructured characteristics. It is difficult to use only mathematical models to describe, and the models must be constantly amended and combined with practical experience in a variety of regulation schemes. In addition, the implementation of the regulation de...

Theoretical description of excitation energy transfer in light-harvesting complexes, for example, in natural photosystems, is a complicated computational problem, though, in principle, it boils down merely to solution of time-dependent Schrodinger equation. To solve the equation one needs the information about the eigenstates and the initial state of the given system. While the second requireme...

This study presents the estimation of reservoir storage capacity using multiresolution Real-Time Kinematic Global Positioning System (RTK-GPS) DEM, in comparison with ASTER and contour-derived DEM. Through RMSE comparisons of the elevation point uncertainty and error analysis, the results shows that the RTK-GPS DEM gave the best results for the reservoir capacity-area power curve estimation, de...