1,256 research outputs found

    Perceptions and Acceptance of Desalinated Seawater for Irrigation: A Case Study in the Níjar District (Southeast Spain)

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    In the context of increasing demand for irrigation water—but, at the same time, with the constraints in the supply from traditional resources—desalinated seawater has been recognized as one of the alternative sources of water to increase the supply for agricultural irrigation. However, its use among farmers has not yet started to expand. Policy makers need to understand what is causing the low acceptance levels of farmers, and how their attitudes could be improved. This is the first study that has conducted an analysis of farmers’ perceptions and acceptance of the use of desalinated seawater for irrigation. The study is based on collected data from a survey completed by farmers in southeastern Spain who do not use desalinated seawater. The main results indicate that desalinated seawater as a water supply source has the lowest acceptance level for farmers. Barriers for its use are price, the need for additional fertilization, and the perception that it would negatively affect the yield and crop quality. The farmers’ general level of knowledge about the impact of using desalinated seawater in agriculture is extremely low. Furthermore, farmers consider it a priority that their startup investment should be subsidized and that water prices should be reduced. Based on the study findings, this paper makes recommendations for the decision-making process in order to improve farmers’ acceptance levels

    Assessment of metals behaviour in industrial soil using sequential extraction, multivariable analysis and a geostatistical approach

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    The main objectives of this studywere to evaluate the degree of Pb, Cu, Zn, Cd, Cr and Ni pollution using pollution indexes and geostatistical approach, and to assess metals dynamic using sequential extraction procedure and multivariable statistical analysis in surface soils and soil profiles froman industrial complex as a base for a correct management in order to avoid health and environmental problems. Results showed that the industrial activity increases both Pb (103 mgkg−1), Zn (526 mgkg−1) and Cu (39 mgkg−1) concentrations and salinity in soil. Pollution indexes showed that industrial soils were moderately contaminated by Zn, Pb, Cu, Cr and Ni as well as a moderate ecological risk was reported. Two main areas were identified: southeast area with the highest metal concentrations, and northwest areawith the lowest levels. Chemical speciation of metals showed that the residual phase was the dominant phase for all metals. However, Pb and Zn were highly associated to the reducible phase (25–30% and 35–40% respectively) and a significant concentration was associated to carbonates (5% for both metals). In contrast, Cu, Cr and Ni were mainly bound to the residual phase (N80% for all metals) with low concentrations retained to reducible phase, and very low concentrations bound to the most labile phases. Cd was the most mobile metal with high concentration associated to exchangeable (5%) and carbonates (15–20%) phases. Therefore, Pb, Zn and Cd represent the greatest risk for human health and the environment

    A New Soil Moisture Agricultural Drought Index (SMADI) Integrating MODIS and SMOS Products: A Case of Study over the Iberian Peninsula

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    25 pages, 9 figures, 4 tablesA new index for agricultural drought monitoring is presented based on the integration of different soil/vegetation remote sensing observations. The synergistic fusion of the surface soil moisture (SSM) from the Soil Moisture and Ocean Salinity (SMOS) mission, with the Moderate Resolution Imaging Spectroradiometer (MODIS) derived land surface temperature (LST), and water/vegetation indices for agricultural drought monitoring was tested. The rationale of the approach is based on the inverse relationship between LST, vegetation condition and soil moisture content. Thus, the proposed Soil Moisture Agricultural Drought Index (SMADI) combines the soil and temperature conditions while including the lagged response of vegetation. SMADI was retrieved every eight days at 500 m spatial resolution for the whole Iberian Peninsula (IP) from 2010 to 2014, and a time lag of eight days was used to account for the plant response to the varying soil/climatic conditions. The results of SMADI compared well with other agricultural indices in a semiarid area in the Duero basin, in Spain, and also with a climatic index in areas of the Iberian Peninsula under contrasted climatic conditions. Based on a standard classification of drought severity, the proposed index allowed for a coherent description of the drought conditions of the IP during the study periodThis study was supported by the Spanish Ministry of Economy and Competitiveness, MINECO (Projects AYA2012-39356-C05 and ESP2015-67549-C3-3) and the European Regional Development Fund, FEDER. Partial funding was also received from the BBVA FoundationPeer Reviewe

    Differences Between and Within Genders in Gender Role Orientation According to Age and Level of Education

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    This study analyses the masculinity and femininity in a Spanish simple made upof 164 adult workers (88menand 76 women). To be specific, the objective was to demonstrate whether age and level of education were related to differences in masculinity and femininity, both when comparing between the two genders and when the comparisons are made within the same gender. The results indicated that the two variables predicted differences in women, but not in men. There were only differences between genders in masculinity and femininity between the ages of 20 and 39, and when the level of education is low. The results appear to support Hofstede’s hypothesis that there are fewer differences between genders in gender role orientation in feminine countries

    DIFFERENCES BETWEEN MEN AND WOMEN WITH A DISMISSING ATTACHMENT STYLE REGARDING THEIR ATTITUDES AND BEHAVIOUR IN ROMANTIC RELATIONSHIPS.

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    R esearch to date has revealed that the association between gender, attachment and the quality and functioning of intimate relationships is complex. This study examined the relationship between gender and attachment styles in attitudes to communication with one’s partner and in the number of past relationships in a sample of 746 Spanish undergraduates. The Relationship Questionnaire was administered to them to determine the adult attachment style. The results revealed the existence of differences according to the adult attachment style and gender with regard to the two measured variables, and a significant effect of the interaction between gender and attachment. Dismissing men reported the highest average scores in the number of past relationships, with significant differences appearing when they were compared with secure and preoccupied men. However, dismissing women did not differ from the rest of the women with other attachment styles. When men and women with the same attachment styles were compared in this variable, the only significant differences were found between dismissing men and women (with the latter reporting fewer partners). In the case of attitudes to expressing feelings to one’s partner, dismissing men reported the most negative attitudes, compared with secure and preoccupied men. Dismissing women, unlike the men, did not differ in their attitudes either from preoccupied or fearful women. Moreover, clear differences were shown between dismissing men and women in these attitudes (more negative in the case of men)

    PERCEIVED BENEFITS AND COSTS OF ROMANTIC RELATIONSHIPS FOR YOUNG PEOPLE:DIFFERENCES BY ADULT ATTACHMENT STYLE

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    Bowlby’s attachment theory suggested that the attachment experiences of early childhood influence adult approaches to close relationships. As a result of these experiences, the child develops typical mental schemas or internal working models. The aim of this study was to analyze how young people with different attachment styles perceive the benefits and costs involved in spending as much time as possible with their partner, and to determine whether their beliefs reflect the internal working models associated with their attachment style. A sample of 1,539 university students responded to the Relationship Questionnaire (Bartholomew & Horowith, 1991), and to a questionnaire about behavioral beliefs (perceived benefits and costs). Results show that young people with different attachment styles hold different beliefs about the consequences derived from engaging in a specific behavior in romantic relationships. Secure and preoccupied individuals perceived more benefits than costs associated with the behavior, whereas dismissing and fearful individuals perceived more costs than benefits. Furthermore, secure and preoccupied individuals rated those behavioral consequences leading to enhanced intimacy or closeness more positively than avoidant individuals, whereas dismissing individuals rated more negatively those consequences that involved a loss of independence. These results confirm that a congruity exists between the beliefs associated with the behavior studied and the internal working models related to each adult attachment style

    Benchmarking in the purchasing function: impact on purchasing performance and business performance.

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    The importance of benchmarking in the achievement of better results in the purchasing function and in overall business performance has been asserted in several textbooks, and in the practitioner and academic literature. However few studies have addressed the implementation of benchmarking in purchasing and its impact on purchasing and business performance. Data was collected from 306 companies and structural equations modeling is used to develop valid and reliable instruments for benchmarking, purchasing performance and business performance. The results show a significant positive impact of benchmarking on purchasing performance and an indirect positive effect on business performance. Implications of the findings for purchasing management are discussed.Catedra Cajamurcia (University of Murcia

    Frequency control support of a wind-solar isolated system by a hydropower plant with long tail-race tunnel

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    Pumped storage hydro plants (PSHP) can provide adequate energy storage and frequency regulation capacities in isolated power systems having significant renewable energy resources. Due to its high wind and solar potential, several plans have been developed for La Palma Island in the Canary archipelago, aimed at increasing the penetration of these energy sources. In this paper, the performance of the frequency control of La Palma power system is assessed, when the demand is supplied by the available wind and solar generation with the support of a PSHP which has been predesigned for this purpose. The frequency regulation is provided exclusively by the PSHP. Due to topographic and environmental constraints, this plant has a long tail-race tunnel without a surge tank. In this configuration, the effects of pressure waves cannot be neglected and, therefore, usual recommendations for PID governor tuning provide poor performance. A PI governor tuning criterion is proposed for the hydro plant and compared with other criteria according to several performance indices. Several scenarios considering solar and wind energy penetration have been simulated to check the plant response using the proposed criterion. This tuning of the PI governor maintains La Palma system frequency within grid code requirements

    Las competencias del orientador en la movilidad profesional

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    Este artículo analiza la evolución del concepto de profesionalidad y justifica la necesidad de establecer —tomando como referencia los perfiles de acción— las competencias fundamentales en el ejercicio profesional del orientador, que pueden adquirirse y perfeccionarse mediante el diseño de itinerarios formativos y profesionales específicos. Además considera la influencia de los rasgos personales y la movilidad profesional elementos básicos de las sociedades actuales, que exigen la adaptación del perfil de competencias del orientador a su contexto social. Se propone un listado de competencias del orientador y se sugiere los procesos para validarlos.This article examines the evolution of the professional concept and argues to determine the counsellor’s core competencies that should be acquired and improved —keeping in mind occupational profiles— by appropiate training trajectories and professional experiences. The influence of personality traits and occupational mobility in current contexts is considered to adjusting counsellor’s competencies. A counsellor’s competencies list it is suggested and more research about this topic it is claimed

    Contribution to Load-Frequency Regulation of a Hydropower Plant with Long Tail-Race Tunnel

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    In this paper, a hydroelectric power plant with long tail-race tunnel has been modelled for assessing its contribution to secondary regulation reserve. Cavitation problems, caused by the discharge conduit length, are expected downstream the turbine where low pressure appears during regulation manoeuvres. Therefore, governor's gains should be selected taking into account these phenomena. On the other hand, regulation services bidden by the plant operator should fulfil TSO (Transmission System Operator) quality requirements. A methodology for tuning governor PI gains is proposed and applied to a Hydro power plant in pre-design phase in northwest area of Spain. The PI gains adjustment proposed provides a proper plant response, according to some established indexes, while avoiding cavitation phenomena
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