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Copyright of Historia Agraria is the property of Historia Agraria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Larhyss Journal is the property of Biskra University, Research Laboratory in Subterranean & Surface Hydraulics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As the classical water-supply looped-network optimization problem is mathematically nonconvex and multimodal, the resulting solution of most approaches is uncertain in the sense of how close it is to the "best" solution. In many cases, this "best"' or "global" solution is invoked and pursued without a clear understanding of its meaning. This paper discusses what is involved in "global" solutions and the role that pipe flow distribution can play to deal with nonconvexity and multimodality in a new context. The author has introduced this new context recently after formulating a new objective function capable of finding that a looped network can be economically more attractive than its related branched one. Therefore, the convenience of an approach dealing with flows and heads, as relevant decision variables, is encouraged in this paper and its advantages enumerated under the new concepts. The entropy approach is studied critically and an example is provided for comparison with the proposed approach. [ABSTRACT FROM AUTHOR]

This paper presents the sizing of the blades of a 1 kW hydrokinetic turbine with 3 blades with hydrodynamic multielement profiles using the Blade Element Momentum theory (BEM). The hydrodynamic profile used was the Eppler 420. The turbine was designed from a water flow velocity of 1.5 m/s with a tip speed ratio of the blade (λ) of 6.325, a pitch angle of the blade section (θ) of 0°, a power coefficient of 0.4382 and a mechanical efficiency of 70%. The Eppler 420 multi-element profile was selected for the design of the blade because it has a high ratio between the lift coefficient and the drag. A 2D computation study in the JavaFoil code of the Eppler 420 profile was carried out in order to determine the optimal lengths of the main element and the optimal flap for a deflection angle of 30° under conditions of a low Reynolds number. [ABSTRACT FROM AUTHOR]

Copyright of Revista Fuentes, El Reventón Energético is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería Hidráulica en México is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista EIA is the property of Escuela de Ingenieria de Antioquia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería y Universidad is the property of Pontificia Universidad Javeriana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The evolution of hydraulic engineering education in Cuba from 1900 to 1959 was presented in a previous paper. In order to analyze in a better way the evolution of this education from 1959 to the present time, we have considered five stages in the time scale. In this paper the first two stages of the revolutionary period, covering from 1959 to 1977, are studied. The 1957 Civil Engineering curriculum was modified in 1961, appearing three specializations in the fifth year, one of which was Hydraulics. With the time, the subjects pertaining to Hydraulic Engineering increased their presence in the Civil Engineer curriculum until 1968 when an independent curriculum for Hydraulic Engineering was approved. The 1962 and the 1968 curricula are presented. [ABSTRACT FROM AUTHOR]

Copyright of Revista EIA is the property of Escuela de Ingenieria de Antioquia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper a historical analysis of two fundamental aspects of hydraulic engineering is made. They are the construction of works and engineering teaching in Cuban context. Evolution of construction and its influence in the formation of professionals can be appreciated. Also, the presence of this professionals has influenced the amount and complexity of works. Here, some social and environmental factors are mentioned, establishing an ancient memory, which has been divided into five parts withholding five centuries. On each part development of works and teaching of this engineering are presented, thus making a historical - logical link between them. [ABSTRACT FROM AUTHOR]

This paper presents the results obtained using a mathematical model, to simulate different situations plugging on issuers irrigation systems micoirrigación in the cultivation of guava in two subunits irrigation the UBPC the Tezón in Ciego de Avila province. The model is that the uniformity of the emitter flow is affected by the hydraulic factor, manufacturing and plugging. For the preparation of the experimental data obtained with the implementation of these procedures has been developed a computational tool using an Excel 2007 worksheet that allows quickly and with a wide margin of safety obtain fundamental results of these calculations. The aim of this work is to simulate seals issuers using mathematical modeling in micro irrigation systems. [ABSTRACT FROM AUTHOR]

The 21st century company faces a new complex economic, cultural and informational scenario. The Cuban management system, following governmental regulations, enforces public enterprise approach to innovation and technology management (ITM). In contrast to the above, the Enterprise for Hydraulic Projects and Investigations in Villa Clara (EIPH-VC) does not have any systematic management action in this sense to improve its general performance. This paper presents the theoretical and methodological approach to systematize the ITM and the first results of its implementation, derived from an incipient but systematic application of the ITM in this company, characterized by the intensive use of knowledge and technology. [ABSTRACT FROM AUTHOR]

This paper presents a procedure in order to measuring and assessing the external client's satisfaction in Cuban technology-based enterprises, using a single project approach with an application case in the hydraulic sector. The procedure is carried out in stages that provide essential outcomes to the organization. As a part of the procedure, "quality attributes and dimensions" of the product are identified. Then, the instrument to assess the client´s satisfaction is designed, validated and applied. Finally, an integral index of the external client's satisfaction is defined. Among the main results of this research are the definition and assessment of the quality attributes that define the projects and an integral index that permits to assess the perceived quality of management from the client's perspective, and allows taking corrective measures and planning actions in order to avoid any possible deterioration of this indicator. [ABSTRACT FROM AUTHOR]

The designers of road (highway) cross-drainage structures frequently use culverts instead of bridges. However, culvert design is usually characterized by some conceptual errors which persist without modification because of lack of critical analysis and knowledge of useful experiences. In this paper, the proposed solution attempts to offer a novel type of hydraulic low cost structures for conveying the surface water through and over the embankment as well as fulfilling the following: first, for the design discharge the culvert suffers no damage to the embankment nor to the pavement and, second, in case the discharge increases the water is allowed to flow over the pavement (embankment) without damage; naturally the traffic would suffer a short interruption. [ABSTRACT FROM AUTHOR]

The paper analyzes the characteristics and operation of Albear Aqueduct, an exceptional work of Cuban engineering of all time, designed by the military engineer Francisco Albear and Lara, who also directed its implementation over the second half of the nineteenth century. This important work was able to meet and exceed the needs of the people of that time with excellent water quality and continues running efficiently to the present. For its excellent design won major national and international awards. [ABSTRACT FROM AUTHOR]

The paper shows the experience in handling the design of Caibarien- Santa Maria key causeway to fit it with the environmental characteristics of the watershed in which it is located. By means of a cause-effect modeling graphic, corroborated by an up-dated informatics software, it is demonstrated the fundamental character that keeping the ocean-island shelf interchange has, as well as the hydrodynamics, in the preservation of the marine environmental characteristics. It is also explained the general strategy that was followed, on the assumption that the causeway is, according to the environmental point of view, a hydraulic construction as a set of its main components: the road layout, the calculation of bridges by hydraulically quasi-homogenous sections, the manner the bridges are located, the off-road induced works and the so-called ecological bridges. [ABSTRACT FROM AUTHOR]

This paper deals with the calculation of a set of inflow and volume values for several return periods for the hydrometric station Huites, Sinaloa, Mexico, by means of the numerical closed and open methods to find the roots for an equation; in this case the bisection algorithm and the Secant method, respectively. The bivariate distribution function for the analyzed variables was a two population Gumbel whose parameters were obtained in a previous research by using a genetic algorithm. The bisection algorithm showed to be the most efficient in estimating volume, resulting in a useful tool which allowed for the estimation of the design events with relative simplicity and could be applied in functions of random variables. [ABSTRACT FROM AUTHOR]

This paper describes an experience in the use of mathematical models and load tests on hydrotechnical structures. The results obtained from the load test performed on the sheet pile of a dock, located in the eastern part of Cuba, are presented. Horizontal and vertical deformations were measured. A comparison is made between the theoretical methods for deformation calculation and the mathematical methods based on the finite-element method. Finally, the coincidence of results obtained from the numerical model and those of a real-scale load test is proved, thus showing that deformations could not become a risk if the dock is subject to a new load system. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia e Ingenieria Neogranadina is the property of Ciencia e Ingenieria Neogranadina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soil moisture is a key state variable in the dynamics of dissimilar processes and natural phenomena. This, together with the development of new methods of estimation of this variable at different scales in space- time, has led to the use of assimilation techniques to improve their estimates. The aim of this paper is to illustrate the potential of such tools in the estimation of soil moisture profiles from the assimilation of surface moisture values in a simulation model. To this end is performed a synthetic study based on the use of Richards's equation for modeling the movement of water flow in the soil. The use of assimilation technique significantly reduces the error estimated profiles with respect to the real ones, and with it avoiding the possible divergence of the solution. In particular the technique Kalman Filter assimilation obtained superior results, in less time, with respect to the technique of Direct Insertion assimilation. [ABSTRACT FROM AUTHOR]

Teaching in Hydraulics is based on theoretical equations and empirical solutions given by researchers. Also results from physical and mathematical models are used. But not always flow behavior can be clearly visualized or, as with physical models, specialized laboratories are required. Therefore, a tool is needed to reproduce, in quality and quantity, the movement of fluids across different types of conduits. This paper deals, for the first time in Cuba, with the application of visual models to visualize flow behavior under different situations. By applying the visual modeling software Flow-3D, solutions to flow problems in channels and pipes can be visually observed, thus enhancing the teacher's action. Also student comprehension is highly improved as he can watch different alternatives of flow under various working conditions. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia e Ingenieria Neogranadina is the property of Ciencia e Ingenieria Neogranadina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water resources systems usually integrate a group of components or subsystems, each with their own set of inputs and outputs. Operating these systems is a continuous process that should be rigorously controlled to insure objectives and goals. The main aspects to be developed for monitoring and studying hydraulic systems operation are: the equipment for acquisition of system variables which characterize its performance and the implementation of software tools to facilitate interpretation of gathered data. In this paper a technology for field variables logging, in deferred time, developed by Hydraulic Resources Group of the Hydraulic Research Center, is presented. Additionally, WinRM application results to Santa Lucía Aqueduct and Sewer Enterprise for water control and management activity support are included. [ABSTRACT FROM AUTHOR]

Copyright of Tecnología y Ciencias del Agua is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In supercritical flow canals it is very important to consider the air - entrainment phenomenon. This phenomenon is needed for the hydraulic design of the canal wall height. In this paper a comparison is made between several existing methods for the air - entrainment determination and a new simpler method is proposed which appears to be as trustable as the best of the existing ones. [ABSTRACT FROM AUTHOR]

The hydraulic jump in circular conduits has not been studied in depth. Some reports even consider that theroretical values of its parameters are not in agreement with the few experimental data available. Theoretical treatment of the problem is hereby presented with calculation expressions and graphics for its solution. Validity of the results is shown provided that all involved coefficients are correctly fundamented. To this end reported test results in the literature are re-elaborated. Comparison between proposed approximate formulas to calculate jump length and an empirical dependence existing within hydraulic properties of these conduits, shows the need to apply the latter in order to obtain reliable results. The paper also calculates the hydraulic jump efficiency in consumption of the excess energy in these conduits. [ABSTRACT FROM AUTHOR]

Copyright of Revista Umbral Científico is the property of Universidad Manuela Beltran and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería Hidráulica en México is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería Hidráulica en México is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The exponential law of flow is revised through dimensional analysis leading to the determination of hydraulic conductivity (HC). But HC depends on the gradient exponent which has limited the use of the exponential law in practice. The paper shows how the velocity can be calculated given the gradient and the properties. A general relationship between hydraulic conductivity and that of Darcy is derived as a function only of the exponent and the gradient. Besides, an excellent correlation is obtained between a gradient quotient (hydraulic over Darcy critical) and the exponent of the gradient in the exponential law, derived from extensive data of experimental results of many authors. Lastly, a correlation between Darcy critical hydraulic gradient and intrinsic permeability is made to estimate Darcy critical gradient when no information is available about the media equivalent roughness. [ABSTRACT FROM AUTHOR]

Geographic information systems (GIS) are an important tool for storing and managing geographically referenced data. They can represent real world through digital data and data from simulation of natural or antropic processes over a given scenario for a given time. GIS has multiple applications. It is widely used in hydraulics and nowadays many resource management systems are incorporating applications. In the Centro de Investigaciones Hidráulicas (CIH) of CUJAE a platform is developed for water resources management. One of its components is GIS. In this paper general characteristics of GIS are explained, development tools and the specifically designed GIS for the Modular Integrated Platform of water resources. [ABSTRACT FROM AUTHOR]

This paper presents a lineal optimization model to solve the hydrothermal coordination problem. The main contribution of this work is the inclusion of the network constraints to the hydrothermal coordination problem and its solution using an interior point method. The proposed model allows working with a system that can be completely hydraulic, thermal or mixed. Results are presented on the IEEE 14 bus test system. [ABSTRACT FROM AUTHOR]

Copyright of Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales is the property of Academia Colombiana de Ciencias Exactas, Fisicas y Naturales and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Looped networks have been used extensively in practice with the advantage of reducing the amount of affected users under a failure situation. The concept of reliability is applied as an attempt to measure quantitatively the possibility of keeping an adequate service level for a given time horizon. From the above, one should expect a looped network to be more reliable than a branched network under similar layout and sizing characteristics. In this paper two quantitative indices to measure expected network behavior are discussed: reliability and tolerance. These indices are calculated and a comparison is made between looped and branched networks. [ABSTRACT FROM AUTHOR]

Ski – jump energy dissipators are widely used in practice because of their well – known effectiveness. Nevertheless, some uncertainty exists associated with the dimensions of the scour – hole appearing downstream of the structure. In this paper a new method is presented in which this problem is solved. This method includes the spillway stability checking as part of the design process and also the stability checking of any other construction near the zone of energy dissipation. Finally, a methodology is suggested for the design of these dissipating structures which includes considering discharges below the design discharge. [ABSTRACT FROM AUTHOR]

The biofilm processes has been profusely used during the last ten years. This has been due to the more and more rigorous standards for wastewater treatment and the necessity of a better use of the space. Biofilm processes include the "submerged fixed bed reactors". Such reactors are characterized by their high buffer capacity as a consequence of the organic load fluctuations originated by the high capacity of adsorption of the biofilm. This paper shows the modeling of an aerated fixed bed submerged reactor at pilot plant scale, for the treatment of a synthetic substrate. An experiment design of 24 was used. Operational variables used were organic matter concentration as COD, hydraulic retention time, packing area and aeration level. [ABSTRACT FROM AUTHOR]

Operation of a well field under automatic control implies important benefits mainly as related to the efficiency of the operation and the quality of service. Although this technology was applied in the country already more than ten years ago, at present it is only used in two water supply systems. The main features that must be taken into account for the automatic control of a well field are described in this paper along with the selection of its relevant variables and criteria for adequate choice of instrumentation. The Cayo Redondo well field of Manzanillo water supply system is introduced as a case study and application example. Finally, the advantages of this technology for aquifer evaluation and monitoring are discussed. [ABSTRACT FROM AUTHOR]

Tension disc infiltrometers are being increasingly used for determining in situ saturated and near-saturated soil hydraulic properties. The objective of this paper was to compare two calculation methodologies for different soil hydraulic properties starting from data measured with a disc tension infiltrometer. The experiment was carried out on packed soil in samples extracted from the Ap horizon of a typic Haplustol soil with a silt loam texture. The disc infiltrometer utilized was of the type that applies water at pressures less than or equal to atmospheric pressure. Calculation methodologies used for the different hydraulic properties were: a) the White and Sully method, and b) the Ankeny method. By comparison and analysis of both methods, it was observed that the Ankeny method was less susceptible to originate error in the estimation of unsaturated hydraulic conductivity, producing values of 59.4 and 21.89 mm h-1 when water was applied at -2 and -4 cm of pressure, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Ingenius, Revista Ciencia y Tecnología is the property of Universidad Politecnica Salesiana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)