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The objective of this study is to show a case study application of the blue print methodology for probabilistic prediction of discharge and sediment yield under extreme events, which was published in previous volumes of this Journal. The study focus on "V Aniversario" basin, which is located in the Cuyaguateje River Basin, Pinar del Río Province, west of Cuba. Using site-based rainfall, discharge and sediment series, and landuse and soil information the KINEROS (K2) model was calibrated and validated. The extreme maxima in the area fitted a theoretical probability distribution EV type II - Fréchet. Results of the hydrological response predictions for a 50-year return event are also shown in this paper. [ABSTRACT FROM AUTHOR]

In last years, many organizations have been given the task of collecting geographic information, which can be used in different contexts for different purposes. Consequently, locating this information becomes a priority for users who need to access it. In this paper a recovery system that manipulates spatial relations between geographic objects is presented. This proposal introduces of novel way the spatial relations to determinate semantic similarity between concepts to solve geospatial queries combining textual and spatial aspects. Another important feature of this system is to present the results in a friendly way, allowing navigate the mapping provided by the system. The indexed information can be easily accessed by users and displayed in a clear and organized to support decision-making way. This tool can be used for both characterization and geospatial location of the soil, as for the management of agricultural soils in Cuba. [ABSTRACT FROM AUTHOR]

From the scientific problem stated on this paper, related to the insufficiency of Agricultural Engineering graduates, the main objective is the pedagogical educative process and the professional education model of this career in the University of Ciego de Avila. There is a study plan which includes the basic and pre-professional levels by means of term papers and disciplines, as well as thesis in the professional level. This is carried out by means of the technological processes in the different engineering systems. This professional education model gives a practical significance to the work. [ABSTRACT FROM AUTHOR]

It is required of methods to evaluate water productivity for the best economic and social use of it, in order to make better decisions as for political and strategies of use in a sustainable way. Water irrigation user need to identify tendencies in the use patterns and levels of efficiency with a view to state goals and to improve the productivity for unit of used volume and/or consumed. The objective of this paper was to present the indicators of water productivity of 17 crops starting from the information obtained in more than 100 field experiments available in the database on water requirements of the Research Institute on Agricultural Engineering (IAgric). The maximum and minimum yields and their respective values of consumption, irrigation water applied and the irrigation water productivity for these crops were determined. Cultivations like the beans, corn, sweet potato and bananas obtain superior yield increments to 100% when the required water is applied to satisfy its water requirement, while cassava obtained values smaller than 50%. The high values obtained of productivity based on the irrigation water applied are not a good indicator of the efficient use of the water for the plants for the conditions of the study area, where they are informed for the analyzed years, percentages of profitable rain of until 41%, replacing this an important part of the needs of the agricultural crops. [ABSTRACT FROM AUTHOR]

The use of indexes to value the water quality facilitates its communication and understanding by specialists and public in general. One of the mostusedis the index proposed by the Canadian Council of Ministers of the Environment(known as CCME_WQI) for its flexibility in the selection of the variables to be considered. In this paper the CCME_WQI was used to evaluate the water quality for irrigation of superficial and groundwater sources of Naranjoriver watershed, Las Tunas province, Cuba. FAO directives and recommendations of the Institute of Agricultural Engineering of Cuba were used to define the desirable values. The results show that the waters are classified as Poor for irrigation. [ABSTRACT FROM AUTHOR]

King Grass production as food for livestock is a priority of the Cuban agriculture at present. Among clones to be developed, the Pennisetum Cuba CT -169 requires a technological package that includes the use of fertilizers and water for an appropriate development of the crop with productions that satisfy requirements of more than 20 animals. The objective of this paper are to determine the productive potential of the forage, to evaluate the number of animals which are able to keep King Grass production with the application of water through stationary and semi-stationary sprinkling irrigation systems in small areas of cooperatives. This low intensity irrigation technique has been selected for delivering irrigation standard to the crop during its vegetative cycle with an irrigation interval of 7 to 10 days allowing cuts to the King Grass starting from 45 days. The irrigation systems designed for 1 ha, response to the outlined needs and the production of them has as premise that the pieces and parts of stationary semi systems contain 76% of components of national production, while the stationary ones only have 40%. The efficiency of water application is evaluated in both cases; as well as yields of green. [ABSTRACT FROM AUTHOR]

Protected crops consist of the use of the so called "tropical greenhouses" that allow the production of vegetables during the whole year, mainly in the hottest months. This productive system is important, because is aimed to guarantee the supply of fresh vegetables of great quality for export, tourism and population. Today, protected crops are recognized in the world as an advanced agricultural technology. It's a relative new system, and being its characteristics are different from the production in open areas, there are no suitable implements, machines and technologies in Cuba to perform cropping activities due to the widely use of tractors of medium and high power. The objective of this paper is to determine the fulfillment of technical and agro technical requirements, including economical-managing and technological indicators of low power tractors to develop different labors such as deep tillage, ploughing, clods crushing, crossing, and soil bed forming. The experimental area chosen for this research was a covered cropping installation model BK-2 widely used in Cuba, and as an energetic source were used the Carraro and MTZ-321 tractors. The house was designed to get yields of approximately 60 ton/ha of vegetables and consists of tunnel's modules of 540 m² placed in 1 ha with the objective of making a better management of the irrigation system, machinery and electric power. A methodology was prepared for the experiment, based in the Technical normative for this kind of research. The tractors used were the non-articulated ones and for they was calculated a strip for turn off of 3,84 to 4,96 m, needed in the covered cropping houses. As results was determined that the productivity obtained by both tractors are similar with the implements used. There are no important differences between the annual labor expenses, but as regard as the transferred expenses the MTZ-321 exceed the Carraro in 33% to 50%, due to higher fuel consumption. All of them fulfilled the agrotechnical exigencies. [ABSTRACT FROM AUTHOR]

Nowadays it is necessary to have sound knowledge in the use of advanced statistical methods due to their leading role in research. In spite of all this, as a whole there are difficulties in learning this subject internationally, and there is lack of a good preparation in Statistics of professionals from other fields. The aim of this paper is to show the new strategies carried out by groups of experts in biometrics, in order to raise the quality of the teaching learning process of Statistics in undergraduate and postgraduate courses at Latin American universities; as well as to show some ways to strengthen the upgrading of human resources in developing teaching and research. The information has been processed from several projects: “Tengo unos datos Que puedo hacer?” still at the University of Granada since 2005; “Metodos y Modelacion Estadestico-Matematico de procesos Biologicos” carried out in Cuba and “Estadistica Aplicada y su contribución a la docencia, investigación y transferencia de conocimiento” developed by Cuba and Argentina (2006-2009) approved by Fondo Argentino de Cooperacion Horizontal (FOAR). The results have been applied in undergraduate courses and postgraduate upgrading at higher education institutions and they are potentially transferred to other universities in Cuba and Latin America. The group of experts in biometrics has been working for more than 20 years, solving problems in university teaching and scientific research in the agricultural sector, responding to the policies and strategic lines of development of the three participant countries. [ABSTRACT FROM AUTHOR]

Technology constitutes one of the strong points to guarantee the successful development of a country. Cuba, being a blockaded country, with financial limitations has not the access to the necessary technology to make its products competitive in the national and international market. The production of scales for the weighing of the cattle constitutes a need for the economy since it has undergone a remarkable damage. Cuba imports the components at very high prices and assembles them. By order of the Area of Livestock of the Ministry of Agriculture since 1998, the task of making electronic scales for the weighing of the cattle was assigned. It is conservatively estimated a national demand of no less than a thousand necessary units to satisfy the need of the genetic enterprises of the country. CEMA worked in the production of several types of scales, which hugely satisfies the national demand. This paper aims at carrying out a research on marketing for the trading of the CEMA TED-1000 V type of scale for the weighing of the cattle. This allows proving that its production is secure for the country, and therefore it is recommended its trading after the approval of the necessary financing for its extension, according to the national demand. [ABSTRACT FROM AUTHOR]

The paper assesses the level of uncertainty in the estimation of reference evapotranspiration in Cuba, by quantifying the errors propagated in numerical models and spatial interpolation using stochastic and probabilistic methods. [ABSTRACT FROM AUTHOR]

This work is part of an investigation carried out by the Center of Agrarian and Rural Development Study, which belongs to the Agrarian University of Havana. This paper's aim is contributing to the socioeconomic sustainability analysis on the cattle sector, San Jose de Las Lajas municipality, by using a statistical-mathematical model. Some information on the social and economic dimensions of sustainability was collected from 2006 to 2010 at the Valle del Peru Company. Different socioeconomic indexes for each of these years were obtained. According to the results of these indexes, the best model was the quadratic tendency to which the relative sustainability rate was calculated. From a practical point of view, this investigation is an important tool for the decision making on the cattle sector. [ABSTRACT FROM AUTHOR]

Soil Channel experimentation, applying the theory of models and the similarity and the dimensions for the evaluation of soil preparation bodies, requires the use of sensors of the forces that arise during the tests related to the rest of the parameters involved in the experimental design previously developed. This paper presents the preparation of the arms of an implement for soil preparation, so that they can be used as dynamometers gauges during tests run of the organs of an attachment for that purpose in agriculture conservation. [ABSTRACT FROM AUTHOR]

This paper aims to analyze the effect of the vibration mode and forward speed in the reduction of the draft force in the vibrating scarifiers. To complete this objective the experimental research was develop in the areas of production of Agroindustrial Complex Sugar "Boris Luis Santa Coloma", belonging to the town of Madruga, Mayabeque province, where they analyzed the effects of self and forced vibrations (factor A) in the tensile strength of a prototype vibrating scarifiers. (Bayamo 81M). Also analyzed the effects of the forward speed (Factor B) in the draft force demand. The results showed that of these factors, the type of vibration exerted a significant influence on the variability of draft force, the forward speed effects was not found significant, as well as the interaction between both factors. Although was not significant the effects of speed, when exhibit values of 4,5 km/h the effects on the variability of draft force were higher than for the speed range of 1,044 to 3,96 km/h. Similarly it was found that the use of forced vibrations in scarification depth allows a reduction in draft force by nine percent, compared with the use of self vibrations. [ABSTRACT FROM AUTHOR]

The Cuban concept of the responsibility of the State in the performing of tasks related to the agricultural mechanization, on the basis of a structure of support for this activity as a part of a social service, did not exist in Venezuela. This paper presents the results of the active participation of Cuban specialists in the introduction of their experience in the creation and set in function of Territorial Stations for Services of Mechanization, being inaugurated in only two years 16 Stations located in 13 states, with definitively or provisional installations. Having Venezuela different modes of property over the land in regard to Cuba, it is necessary that the Stations were organized not as in our country with machinery of the existing Productive Entities, but with the creation of an independent national enterprise. [ABSTRACT FROM AUTHOR]

In Cuba the biogas installations are an important alternative for the processing of organic wastes in agricultural farms, and so reducing the contaminants and improving its quality as fertilizer, obtaining a renewable energy, the biogas. This combustible gas can be used for food cooking, water heating, the generation of electricity and domestic lighting. In the implementation of the strategy for facing climatic change drew up by the Ministry of Agriculture of Cuba it is considered a measure for the reduction of carbon emission consisting in "Reduce the consumption of combustibles of fossil origin using renewable sources of energy". The paper shows a methodology for make easy the analysis and calculation of the parameters for the construction of ixed dome biodigesters. [ABSTRACT FROM AUTHOR]

This paper shows the development of software for the intelligent control of a six degree of freedom robot manipulator, with artificial vision techniques for the intelligent identification of objects by means of pattern recognition using an artificial neural network. A method of images segmentation, based on regions growth by pixels grouping, was implemented for the objects detection. a mathematical model, based on an alternative trigonometric method, was developed to solve the inverse kinematic problem of this robot. The system was tested on a satisfactory way; identifying different kinds of objects with a high percent of certainty and determining their location in the workspace of robot. [ABSTRACT FROM AUTHOR]

This paper presents a novel feedback technique for fluxgate magnetometers based on second harmonic detection method. This new technique mainly consists of the injection of a sample output current in the excitation coil, thus the resultant magnetic field will be in opposition to the external magnetic field object of measurement. This kind of compensation has been conceived for its implementation on integrated fluxgate microsensors. They are used for systems of gyroscopes and electronic compasses in the inertial control of autonomous agricultural vehicles in Precision Agriculture. [ABSTRACT FROM AUTHOR]

With a view to evaluating the possibility of non invasive sensing of soil compaction by means of the application of a variable electromagnetic field, a theoretical - experimental study of the interaction < electromagnetic field-soil > is made, by using finite element simulation, as well as experimentation in a soil deposit. In a previous paper the influence on the soil response to the action of a variable electromagnetic field is determined in function of the excitement frequency of a field-generator coil and of the distance between the field-generator coil and a receiver coil, measured through the current induced in the receiver coil. Also, validation criteria of the use of finite element analysis during the study of the interaction electromagnetic field - soil, were obtained. In present work, using this analysis method, the possibilities of sensing of soil compaction by means of the application of an electromagnetic variable field is studied. As a result, a high correlation (R²=0,96) among the soil electric conductivity and the density of the induced in a receiver coil current is obtained. Experimentally, increments of electric conductivity of a compacted red ferralític soil were evidenced with increases of soil moisture and compaction, measured through their apparent density. Soil electric conductivity and therefore induced voltage in the receiver coil, correlated with soil compaction, oscillating R² between 95,9 and 98,4% for different soil moisture levels. [ABSTRACT FROM AUTHOR]

This paper gives a characterization of the transmitter Sprayhead D3000 in evening and daytime schedules placed at 1 and 2 m height on a test bench outdoors. The equation of the transmitter, the medium intensity of application, effective range diameter, the coefficient of uniformity, distribution uniformity and an analysis of the distribution pattern were determined. The results were the equation of transmitter with a correlation coefficient of 0,9964, the medium intensities showed lower values during daytime hours to 2 m height of 3,61 mm / h, while the effective range diameter reached values of 13,4 m at night at a pressure of 280 kPa and the coefficient of uniformity of 89,4% at a pressure of 190 kPa; on the distribution pattern there were not significant differences observed. [ABSTRACT FROM AUTHOR]

This paper is on the investigation of the durability of the camshaft and its bearing in the Russian engine VAZ, according to the technology developed by the Transport Enterprise, Ciego de Avila. This research shows that the obtained bearings using Babbitt B83 originate a friction pair cast iron - Babbitt B83. This guarantees smaller wear speed and smaller volume wear by comparison with the original one composed by cast iron and aluminum. The recovery cost is lower than the price of the new pieces/components. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyze the quality of the mechanical harvest of rice seeds, carried out by the New Holland L521 rice harvester machines, at the Rice Farm "Los Palacios". Their technological parameters were evaluated depending on the quality of the harvested product, taking into account some aspects such as: the entire, peeled and/or broken grain, the impurity content and total losses. This resulted in values of 5,2-6,4% for peeled and/or broken grain in the five agricultural yields. On the other hand, the impurity content was among 8,3-9,6%, so that both parameters exceed the established limits. This is mainly caused by: the bad regulation of thresh, the work speed and the poor training of operators. These results allow decreasing losses. During the harvest losses decreased from 206kg/ha to 85kg/ha which represents an economic effect of $ 316 202.04 pesos. This also permits to stop investing about 184 793.4 USD on rice for our population feeding. [ABSTRACT FROM AUTHOR]

The finite elements method has been widely used in the simulation of the soil mechanical response. The constitutive models are the mathematical support core of this method and Duncan and Chan's is one of the most used. Therefore, the aim of this paper is to determine accuracy in the prediction of three Cuban clay soils' relationship strain vs. deformation. The soils mechanical properties are determined and the constitutive equations are made in the software Mathcad 14 to accomplish this goal. The results show the model has a large capacity to predict accurately the relationship strain vs. deformation of these soils when there is a plastic failure. However, the model is not able to predict the tensions changes caused by softening or hardening deformations. [ABSTRACT FROM AUTHOR]

The aim of this article is an analysis on the technical and exploitation indicators of the cane harvester machine Case-7000, used in different Agriculture Cooperatives, such as: "Gilberto Aguilar"," Veracruz", "Concordia", "San Carlo # 1" and " Desembarco del Granma". All of them belong to the Sugar Enterprise/Company "Batalla de las Guásimas", Vertientes, Camaguey. This evaluation was made during 29 labor days, 2009, in periods of 12 hours each. So that there was a total of 1152 hours and 15 089, 78 t obtained on the basis of chronometry method. The technical and organizational causes as well as an economical evaluation to analyze their influence on the company production results are described on this paper. [ABSTRACT FROM AUTHOR]

The objective of this paper was determining irrigation management in guava tress on urban agricultural conditions. The research was carried out in a plot at "Celia Sánchez" agricultural cooperative, located in Habana del Este municipality. To substitute the soil water was used drip irrigation with fixed intervals and dosage. The results showed that an adjustment in the irrigation dosage during the first period, depending on the demand. During the development season of the crop, irrigation dosage & frequency used resulted acceptable with 90% the irrigation improvement. On the other hand, it was demonstrated that maintaining high levels of soil moisture produce a positive effect on crop yield and size of the fruit, getting with this irrigation management higher amounts of fruits and crop yield up to of 36,7 t/ha. [ABSTRACT FROM AUTHOR]

The popular production of rice in Cuba is one of the alternatives that the government of our country has taken to resolve the difficult economic situation that it faces, especially in the supply of such precious cereal to the population. During the mechanization of popular rice exists a high national demand of mechanized technologies for the threshing of popular rice, due to the use of rice threshers made empirically and with own resources by the popularizers what becomes the actual reality, but the results are not the really desired due to the insufficient technological requirements of these machines during the rice threshing process showing designing deficiencies; they lack of designs scientifically based, which brings machines with high losses and low productivity during rice threshing, besides that there is not enough information about today's existence of these machines in the country. In the present paper, a diagnostic of several popular rice producers is applied, owners of this type of machinery, residents in many cities; belonging to Granma, Holguin, Habana, Pinar del Rio and Villa Clara provinces, with the aim of evaluating the state and actual use of the stationary rice threshers for popular production; in the field, the study diagnostic was also automated in the microsoft excel system with the aim of analyzing quantitatively and qualitatively the obtained results. The main result obtained established to visualize the existing technical problems in production and exploitation of the stationary rice threshers. [ABSTRACT FROM AUTHOR]

This research paper show the results of the dosage test carried out in the V-20 seeder machine using amaranth seed. A platform the results of the dosage test carried out in the V-20 seeder machine using amaranth seed. A platform test was built at the National Standardization Center for Agricultural Machinery (CENEMA) facilities, using the Mexican Norm: "Method for the evaluation of seeders and/or fertilizing machines with mechanical traction with dosimeter disk" and the Cuban 34-50 Norm "Grain seeder, a methodology for carrying out tests". The physical-mechanical properties, the dimensional characteristics of the seed related to the sowing process, and the work quality indexes for the seeder were determined. The mean values of seeds length, width and thickness were 1 448, 1 263 and 822 µm respectively, while the volumetric mass was 802 kg·m-3, with 7.4% of humidity and the 1000 seeds weight was 0.93 g. The results indicate significant differences among seeds dosed quantity averages in each exit due to the forward speed and number of bodies of the seeder. [ABSTRACT FROM AUTHOR]

The constitutive models of critical state are among the most employed for soil compaction simulation by means of finite element method. This paper has the objective to determine the influence of soil bulk density on elastoplastic parameters of Rhodic Ferralsol soil. Triaxial and compression uniaxial tests were carried out to remoulded samples, with a bulk density of 1.1; 1.175; 1.25 Mg m-3, and gravimetric moisture content of 25 kg g-1. The obtained values of variables analyzed can be used as input data to modeling soil compaction by finite element method and allow to know critical state variables behaviour of one of the Cuban soils with major economic importance. [ABSTRACT FROM AUTHOR]

The paper was developed with the objective of comparing the effect of two organic fertilizers EcoMic and humus on tomato (HA3019 variety) cultivated in greenhouse on red Fertilitic compacted soil. The study was carried out in The Training Production Center (CCP) of Cuban Association of Agricultural and Forest Workers (ACTAF) during the winter 2005. The treatment 1 consists in applying humus (2 kg/m²), before transplanting and EcoMic (1 kg/m²), after transplanting. The treatment 2 consists in applying humus (2 kg/m²), before transplanting and the same quantity 10 days after. The yield obtained in T1 was higher (8,4 kg/m²) than T2 (95,01 kg/m²). Regarding with fruit category, the higher quality was found when EcoMic was applied. Economically, the greater net profit (8 368 pesos) and the greater benefit cost relation (1,88) was obtained in treatment 1. With the application of this product, better yields can be achieved, which don't contaminate the environment. [ABSTRACT FROM AUTHOR]

Nowadays, world has developed treatment and reuse technology for sewage waters, obtain and apply them is too expensive for our country. This situation favours the search for alternatives appropriated for Cuban conditions and budget, taking into account WHO's Guidelines. In stream short distance with a highly content of urban wastewater mainly, there were carried out preliminary studies with the purpose to foresee polluted surface water quality, from checking physic and chemist indicators. This paper is aimed at estimating water quality starting from parameters' determination: pH, electrical conductivity, total solids and nitrates content. The study was carried out in Guachinago stream, one of Luyanó river flowing, locating at San Miguel del Padrón municipality in southeast of Havana city. To fulfil this objective, we start from the fallowing of those indicators cited above in selecting points to seek contaminating source surveys. Water quality was determined through the collected data statistic analysis. [ABSTRACT FROM AUTHOR]

Modelling processes involved in water movement on the soil generally requires solutions using the general equation of water flow for non saturation condition, proposed by Darcy-Buckinghan. In this approach the function hydraulic conductivity-soil moisture K(θ) constitutes a fundamental soil property to determine for each field condition. Many of the methods developed for the measurement of K are based on simplifying assumptions, such as the unit gradient and the choice of fixed models for the K(θ) relation. The need of quick, simple, and inexpensive methods to measure K(θ) in the field using a large number of replicates has also led soil physicist to develop simple methods. One of these methods is the parameterized equation proposed by Reichardt that uses parameters of the equations that explain the internal water drainage process, and that naturally leads to the exponential character of the K(θ) relation. The objective of this paper is to estimate the K using parameterized equation in a Ferralsol soil. Results show that this equation represents a more rigorous estimation of K(θ), compared with the methods that assume unitary gradient. [ABSTRACT FROM AUTHOR]

The present paper was carried out at the Basic Unit of Cooperative Production Camilo Cienfuegos, belonging to the urban farm of the municipality of San Miguel del Padrón, Havana, Cuba. The study has as objective, to know the yield response of the sorghum (bicolor Sorghum, variety V-4) cultivated under dry conditions devoted to animal feeding in Urban Agriculture. The experiment was developed on an alluvial soil from June to September of 2006 with an occurrence of 326,9 mm of total rain fall. The yield (4,86 t/ha) showed that the rain fall allowed an optimal soil moisture for all biological cycle of the crop, as well as to recommend the sowing it in the wet months, without the needed of applying supplementary irrigations. [ABSTRACT FROM AUTHOR]

This paper tries about the development the sprinkler irrigation of low intensity in the Cuban agriculture, in which the reason of the rescued of this irrigation technique is based, under the current conditions and that it motivated this new re-election. They are given, also, to know the historical antecedents of the development of this technology in Cuba where this system is characterized in its different variants. With the world development of the sprinkler irrigation plastics systems our country has advanced also. For that reason, the new focuses of the portable sprinkler of low intensity, and the future lines of work, are exposed. [ABSTRACT FROM AUTHOR]

The objective of this paper is to determine the value of the pH on the condensed vegetable obtained from the juice concentrators, its variance depending on the kind of citrus fruits and its maturity as well as to determine the amount of sodium hydroxide needed for its treatment, to be used to feed the boilers. For this study many samples of pH were taken during the campaign 2008-2009, in a 7 month period. The values of pH were compared to the fruit ratio obtaining a correlation of 0,00149, and by statistics methods it is found that the condensed vegetable pH is constant during the hole campaign and that it is possible to use it to feed the boilers adding to every cubic meter 10,17 g of sodium hydroxide to increase values of pH, from 4 to 8. [ABSTRACT FROM AUTHOR]