bluuebunny/crossref_metadata_2025 huggingface dataset:
The assessment of compliance with feeding schedule of introducing particular products into infant diet, including mothers' age, education and place of residence
Authors: Malczyk Ewa , Wąsat Weronika
Published: December 2015

Wstęp

Okres niemowlęcy to czas do ukończenia pierwszego roku życia. Jest to najbardziej dynamiczna faza rozwoju psychicznego i fizycznego dziecka. Jednym z najważniejszych czynników wpływających na jakość tego rozwoju jest prawidłowe odżywianie. Światowa Organizacja Zdrowia określa karmienie piersią jako najlepszy i najwłaściwszy sposób karmienia niemowlęcia w pierwszym półroczu życia. Po tym czasie dietę dziecka należy rozszerzyć o pokarmy uzupełniające. W Polsce w 2007 r. opublikowano schemat żywienia niemowląt, który uwzględnia sposób karmienia oraz czas i rodzaj wprowadzania do diety dodatkowych produktów. Celem pracy była ocena zgodności wprowadzania poszczególnych produktów do diety niemowląt w odniesieniu do schematu żywienia, z uwzględnieniem wieku, wykształcenia i miejsca zamieszkania ich matek.

Materiał i metody

Badanie przeprowadzono wśród 283 kobiet, matek 13–24-miesięcznych dzieci. Zastosowano autorski kwestionariusz ankiety dotyczącej realizacji zasad żywienia niemowląt i subiektywnej oceny realizacji tych zaleceń.

Wyniki

Zgodność wprowadzania poszczególnych produktów do diety niemowląt w odniesieniu do schematu żywienia, bez względu na wiek, wykształcenie i miejsce zamieszkania ich matek, była na niskim poziomie. Produkty mleczne oraz przekąski słodkie ankietowane matki wprowadzały do diety dziecka w nieodpowiednim miesiącu ich życia. Ponadto respondentki nie uzupełniały diety niemowlęcia witaminą K w zalecanym okresie, tj. od 2 tygodnia do ukończenia 3 miesiąca życia. W odniesieniu do schematu żywienia, kobiety lepiej oceniały zgodność wprowadzania przez siebie poszczególnych produktów do diety niemowląt niż wynikało to z przeprowadzonej ankiety.

Wnioski

Z uwagi na niską ocenę zgodności wprowadzania poszczególnych produktów do diety niemowląt w odniesieniu do schematu żywienia, celowa jest systematyczna edukacja matek w tym zakresie.
Las Desigualdades de Heisenberg. Interpretación y didáctica
Authors: Alemañ Berenguer Rafael Andrés
Published: December 2015

La importancia primordial del inadecuadamente denominado “Principio de Heisenberg” en la física cuántica,no ha evitado una gran cantidad de malentendidos sobre el mismo. Para caracterizar tales malentendidos, 25profesores de física y química de enseñanza media fueron sometidos a un breve cuestionario escrito. Ningunode ellos ofreció una respuesta correcta, y sus contestaciones revelaron que los errores surgen de su confusiónsobre los fundamentos de la física cuántica así como la utilización de estrategias de aprendizaje equivocadas.
La Geometría de la Naturaleza: Benoit Mandelbrot
Authors: Arguedas T. Vernor
Published: December 2015

Este matemático polaco francés norteamericano gozó siempre de una gran reputación, que se acrecentó con elredescubrimiento de conceptos que condujeron a la dimensión fractal y a los fractales. ¿Existe una matemáticaque modela de manera acertada a ciertos procesos de la naturaleza? ¿Es sencilla esta matemática?
Un taller de simulaciones: Fathom, GeoGebra y Excel para resolver problemas controversiales de probabilidad
Authors: Ramírez Arce Greivin
Published: December 2015

El taller pretende utilizar la simulación, en Fathom, GeoGebra y Excel con el fin de desarrollar el pensamiento instin-tivo y confrontarlo con el pensamiento analítico en el estudio de las distribuciones y probabilidades condicionales,y que lo anterior ayude a resolver problemas considerados controversiales de probabilidad. Los participantes traba-jarán con actividades guiadas, podrán apreciar la riqueza didáctica de la simulación hecha con paquetes dinámicosy comparar las potencialidades que cada uno ofrece en la solución de diversos problemas.
George Pólya: el razonamiento plausible
Authors: Arguedas T. Vernor
Published: December 2015

Presentamos algunos aspectos de la vida del gran matemático , Geoge Pólya así como sus ideas acerca de las téc-nicas para enseñar matemáticas por medio de la resolución de problemas y una aproximación a su concepto depensamiento plausible.
Edición de gráficos con Inkscape y Gimp
Authors: Vindas Monestel Karen
Published: December 2015

En este trabajo se muestran las herramientas básicas para la edición de gráficos utilizando los programas Inkscape y Gimp.
Factorización incompleta de Cholesky como técnica de precondicionamiento
Authors: Alpízar B. Geisel Y.
Published: December 2015

Se expone la factorización incompleta de Cholesky como técnica de precondicionamiento. Se presentan experimentos numéricos que muestran la eficencia de este precondicionador, estudiando los tiempos de ejecución al resolver sistemas lineales con el método de gradiente conjugado precondicionado.
Personalizar un entorno para listas de ejercicios con el paquete answers
Authors: Mora Flores Walter
Published: December 2015

Resumen: En este artículo se hace la implementación de varios entornos personalizados para hacer listas de ejercicios (y sus soluciones) con el paquete "answers" de LaTeX. El propósito que se persigue es hacer que el uso de este paquete sea un poco más amigable en la edición de libros y de material didáctico en general

Palabras clave:  LaTeX, paquete answers, listas de ejercicios en Latex.

Abstract:  In this article several personalized environments are implemented to make lists of exercises (and corresponding solutions) using the LaTeX "answers" package. The purpose is to ease the use of this package for book and general didactic material edition.

KeyWords:  LaTeX, answers package, LaTex exercise lists.
Metodología para los procedimientos de solución de problemas sobre Ecuaciones Diferenciales
Authors: Locia Edgardo , Mederos Otilio , Morales Armando , Rodríguez José M. , Sigarreta José M.
Published: December 2015

En este trabajo, se propone una metodología para favorecer la enseñanza y aprendizaje delos procedimientos de solución de problemas sobre ecuaciones diferenciales, a nivel universitario. Loselementos teóricos y metodológicos se basan en el proceso de resolución de problemas desarrollado apartir del enfoque histórico cultural de Vigotsky y Teoría de la Actividad de Leontiev. En la propuestase resaltan dos aspectos fundamentales que garantizan su efectividad en la práctica docente, poruna parte, se propone una clasificación y caracterización de los problemas matemáticos (problemasestructurales y problemas reductivos). Por otra parte, a partir de la caracterización desarrollada, seestructura una estrategia de solución basada en las tres fases fundamentales asociadas con la Teoríade la Actividad: orientación, ejecución y control, las cuales permiten evaluar el aprendizaje a lo largode todo el proceso.
Una propuesta para la enseñanza del teorema de la función inversa
Authors: Ugalde William J.
Published: December 2015

El objetivo es presentar el teorema de la función inversa y algunos de sus principalescorolarios. Este teorema es central en el estudio del cálculo en varias variables, y tradicionalmentesu presentación se hace de manera negligente en cursos que tienden a dar poco énfasis al análisis,lo cual puede no ser conveniente para estudiantes de las carreras de enseñanza de las matemáticas,matemática pura y aplicada, y carreras afines.
Una fórmula que relaciona a los números primos con la función parte entera y los números triangulares
Authors: Braddock S. George
Published: December 2015

El máximo común divisor entre un número primo p y cada uno de los enteros positivos menores que p es igual a 1 y, como el máximo común divisor se relaciona con la función parte entera según una fórmula explícita dada por el matemático brasileño M. Polezzi (1997), entonces se halló una interesante proposición que relaciona los números primos, la función parte entera, los números cuadrados y los números triangulares. Esa proposición sirve como un nuevo test para probar la primalidad de un número.
Estudio de las funciones en situaciones variacionales. Resultados de la implementación de una secuencia de actividades
Authors: Vrancken Silvia , Engler Adriana , Giampieri Maria L. , Müller Daniela
Published: December 2015

El presente artículo incorpora algunos resultados obtenidos al investigar cómo favorecer el desarrollo del pensamiento y lenguaje variacional en estudiantes de primer año de Ingeniería Agronómica. Se presenta una secuencia de actividades para analizar aspectos variacionales del concepto de función y los resultados de su implementación. Se centra la atención en la forma en que el estudio de procesos de variación permite construir acercamientos significativos para la comprensión y el uso de las funciones como modelos de situaciones de cambio. A pesar de las dificultades, se observa que su desarrollo favoreció el surgimiento de argumentos variacionales, partiendo de los conocimientos que los alumnos manejan desde sus experiencias previas.
Algunas reflexiones en torno a los números irracionales
Authors: De León Urbina Mario
Published: December 2015

El conjunto de los números irracionales es un tema de especial interés, debido a que se encuentra en el Programa de Estudios de Matemática de educación secundaria costarricense. Conocer algunos resultados permitirá a los docentes de Enseñanza de la Matemática reflexionar sobre este conjunto y las representaciones que se hacen, tanto del conjunto como de sus elementos, y así aportar herramientas para la reflexión y la búsqueda de estrategias metodológicas, con el fin de lograr una enseñanza óptima de este tema.
Textos reproducibles y dinámicos con PythonTeX
Authors: Cuevas A. Jesús H. , Rodriguez A. Juan J.
Published: December 2015

En este artículo se describe el proceso de instalación y utilización del paquete PythonTeX en la elaboración de un texto reproducible y dinámico. Se indican los requisitos tecnológicos y el protocolo de su operación a partir de ejemplos en que se realizan operaciones con matrices y se hacen cálculos elementales de estadística descriptiva.
Influencia de altas densidades de plantación en el poder calorífico y propiedades físicas de la madera para la especie Gmelina arborea Roxb. ex Sm.
Authors: Salazar-Zeledón Estephanía
Published: December 2015

Se determinó la relación entre el poder calorífico de la especie Gmelina arborea y la densidad de plantación en cultivos de corta rotación, en Cañas, Guanacaste, Costa Rica. Se evaluaron dos propiedades físicas de la madera; el contenido de humedad (%), densidad aparente (g/cm3) y la relación con el poder calorífico (kJ/kg) para tres tipos de densidad de plantación a 5000 árb/ha, 10000 árb/ha y 20000 árb/ha, a un año de edad en distintas posiciones del árbol. La variación del poder calorífico encontrada en los tres tratamientos estuvo entre 15840,98 kJ/kg y 16134,95 kJ/kg. El mayor poder calorífico fue el de densidad de siembra con 20000 árb/ha. Se concluyó que la densidad de la plantación (árb/ha) no afectó el poder calorífico de la especie pero sí las propiedades físicas de la madera que al mismo tiempo influyen en el aumento y disminución de esta propiedad química.
Reducing bias and quantifying uncertainty in watershed flux estimates: the R package loadflex
Authors: Appling Alison P. , Leon Miguel C. , McDowell William H.
Published: December 2015

Many ecological insights into the function of rivers and watersheds emerge from quantifying the flux of solutes or suspended materials in rivers. Numerous methods for flux estimation have been described, and each has its strengths and weaknesses. Currently, the largest practical challenges in flux estimation are to select among these methods and to implement or apply whichever method is chosen. To ease this process of method selection and application, we have written an R software package called loadflex that implements several of the most popular methods for flux estimation, including regressions, interpolations, and the special case of interpolation known as the period‐weighted approach. Our package also implements a lesser‐known and empirically promising approach called the “composite method,” to which we have added an algorithm for estimating prediction uncertainty. Here we describe the structure and key features of loadflex, with a special emphasis on the rationale and details of our composite method implementation. We then demonstrate the use of loadflex by fitting four different models to nitrate data from the Lamprey River in southeastern New Hampshire, where two large floods in 2006–2007 are hypothesized to have driven a long‐term shift in nitrate concentrations and fluxes from the watershed. The models each give believable estimates, and yet they yield different answers for whether and how the floods altered nitrate loads. In general, the best modeling approach for each new dataset will depend on the specific site and solute of interest, and researchers need to make an informed choice among the many possible models. Our package addresses this need by making it simple to apply and compare multiple load estimation models, ultimately allowing researchers to estimate riverine concentrations and fluxes with greater ease and accuracy.
Self-Neglect: Ethical Considerations
Authors: Day Mary Rose , Leahy-Warren Patricia , McCarthy Geraldine
Published: December 2015

Self-neglect is a significant international public health issue. Estimates suggest that there may be over one million cases per year in the United States. Aging populations will put more people at risk of self-neglect. This chapter presents background literature, self-neglect definitions and policy context, risk factors, and a brief overview of research on perspectives of self-neglect from both clients and community health and social care professionals. A case study is presented from the perspective of an individual and is used to explore ethical issues therein. A person-centered assessment within a multidisciplinary team approach is required for building a therapeutic relationship with clients. Capacity is a central issue in the management of responses to self-neglect. Ethical considerations of importance for community health and social care professionals include beneficence and nonmaleficence, autonomy and capacity, and respect for people's rights and dignity. A model of ethical justification is presented to explain dilemmas, challenges, and actions. Competence of professionals, multidisciplinary team working, informed consent, privacy, confidentiality, and best interest are also critical considerations. Effective decision making by an interdisciplinary team of professionals needs to be person-centered and give due consideration to the best interest of self-neglecting clients. The purpose of this chapter is to provide an in-depth discussion and examination of ethical issues and challenges relating to self-neglecting clients.
Temporary Agency Work as a Means of Achieving Flexicurity?
Authors: Håkansson Kristina , Isidorsson Tommy , Kantelius Hannes
Published: December 2015

After decades of debate about flexibility, flexicurity has become a new buzzword in working life. Flexicurity refers to both the employer’s demand for flexibility and the employee’s demand for security. Thus, the idea is to solve the flexibility–security trade-off. There is also a discussion that mentions temporary agency work as one way of creating a flexicurity system. The flexibility potential is not called into question—numerical flexibility is a quite common motive for using temporary agency workers. However, the security dimension has to be scrutinized. The aim of this article is to analyze the temporary work agency industry’s potential for providing the security dimensions of the flexicurity model in a Swedish context. The study is based on a survey of whitecollar temporary agency workers in Sweden (n = 533). Overall, the vast majority do not perceive security. Our most important result is that both the work agency and the user firm have a dual impact on the agency workers’ perception of security.
Joint Responsibility at its Peak – Searching for a New Nordic Unemployment Model
Authors: Dahl Tora
Published: December 2015

Earlier research has shown that the Nordic Ghent systems seem to be weakened. The unemployment insurances administered by the unions have experienced a decline in numbers of members, very similar to the drop in trade union membership. This article takes its point of departure in previous research into the decline in the membership densities of unemployment insurances in several Nordic countries. The article examines these tendencies and focuses on a new and rather atypical example of organizing unemployment systems in a Nordic context, namely that of the Faroe Islands. Based on interviews and documentation analysis, the article describes the system extensively and argues conclusively that the Faroese unemployment insurance system is an example of the deeply rooted Nordic negotiation tradition, albeit in a new context in which the labor market parties stand united to ensure the system’s autonomy from political influence.
Experiences from Implementation of Lean Production: Standardization versus Self-management: A Swedish Case Study
Authors: Oudhuis Margareta , Tengblad Stefan
Published: December 2015

In this article, we discuss important aspects of the perceived problematic relationship between self-management and standardization. The article presents data from three case studies conducted within manufacturing companies in Sweden, where the popularity of lean production has led to a renaissance for short-cycle and standardized assembly work in settings that traditionally have made use of sociotechnical production design. The data suggest that the implementation has not contributed to an increased commitment, smooth operations, and capacity for change and innovation. Despite these not so positive results, it is argued that it is possible to combine self-management principles with lean production and standardization if 1) the implementation of lean is done with a contextual sensitivity, 2) a balance is reached between the use of standards on the one hand and work enrichment on the other, and 3) a feeling of ownership as regards both implementation and production process is upheld among the product on personnel.
Trade Union Responses to Transnational Labour Mobility in the Finnish-Estonian Context
Authors: Alho Rolle
Published: December 2015

This article examines trade union strategies in relation to labor migration in Estonia and Finland, drawing on face-to-face interviews with trade unionists and official union statements. The study considers the national trade union strategies located in two separate but interconnected localities that represent different approaches to market economy. Previous research suggests that the national industrial relations system is a key factor in explaining unions’ labor migration strategies. Unions operating in liberal market economies are claimed to be more open toward immigration and more inclusive toward immigrants than unions in coordinated markets. This study analyzes the extent to which this theory holds in the context of Estonia and Finland—Finland representing a coordinated market economy and Estonia a liberal market economy. Furthermore, the analysis examines how the emergence of a translocal labor market, resulting from the geographical vicinity and linguistic affinity between Finland and Estonia as well as from free mobility within the EU, is reflected in trade union approaches to labor migration. The study finds that Finnish trade union strategies influence labor mobility, whereas Estonian trade unions remain bystanders in the issue.
(De)stabilizing Self-Identities in Professional Work
Authors: Buch Anders , Andersen Vibeke
Published: December 2015

It is characteristic of much professional work that it is performed in ambiguous contexts. Thus, uncertainty, unpredictability, indeterminacy, and recurrent organizational transformations are an integral part of modern work for, e.g., engineers, lawyers, business consultants, and other professionals. Although key performance indicators and other knowledge management systems are used to set standards of excellence for professionals, the character of professional work is still flexible, open to interpretation and heterarchical. The very successfulness (or unsuccessfulness) of the work is established in a complex work context where various goals, interests, and perspectives are mediated, altered, contested, mangled, and negotiated in a process of sense-making. The work context is heterogeneously populated by various actors (e.g., the customer, the manager, the colleagues) and actants (e.g., quality systems and technical equipment) that give “voice” to (conflicting) interpretations of what constitutes successful work. Thus, the professionals must navigate in a very complex environment where the locus of governance is far from stable. These characteristics of professional work seem to have implications for the way professionals make sense of their work and their own identities. The identity work of professionals is interwoven with their professional training and career background. With an academic training and a professional career, the individual typically identifies with the profession’s values and adopts a certain way of seeing and approaching the world. This professional outlook typically will constitute the basis of the individual’s appraisal of the work and lay out a horizon of expectations in relation to fulfillment, self-realization, and job satisfaction. In this way, the construction of self-identity becomes the yardstick for the individual’s sense-making and, a fortiori, for the individual’s sense of meaningful work. In this paper, we will claim that the ambiguity involved in professional work becomes a potential strain on the identity construction of the employees engaged in professional work and a potential source of enthusiasm and self-fulfillment. On a conceptual basis, the paper develops three interpretative frameworks that are useful in understanding how professionals deal with ambiguity in professional work. To illustrate this point, the paper refers to qualitative material from a research project conducted in six Danish knowledge-intensive firms. Referring to this empirical material, we discuss how professionals perceive and relate to their work and the role played by professionalism in this relation. Drawing on neo-institutional theory our paper discusses how professionals draw on different frameworks of meaning in order to stabilize their identities.
Men Who Stop Caring: The Exit of Men from Caring Occupations
Authors: Warming Kenn
Published: December 2015

In recent years, initiatives have been taken to attract more men into caring occupations. However, there has been much less focus on retaining these new male workers. This article builds on qualitative interviews with 11 Danish men who after working in the caring sector decided to leave for other occupations. A factor often presented as influential for the men’s exit concerns the social working environment. In the interviews, the men discuss the pressure to assimilate to the existing and established female-dominated culture. They feel excluded and socially isolated. Several of them have been directly criticized or disqualified as not being “real” men by their female colleagues. As a result of a growing bureaucratic demand for control and registration of work procedures, several men feel that they do not have adequate resources and time to provide the level of care that is needed. They become disillusioned and frustrated and choose to seek employment elsewhere. Some men cannot come to terms with close physical contact and “smells,” for example, changing diapers on infants or bathing old people. They cannot handle the thought of having their intentions misinterpreted, for example, when playing and being physical with children, and being potentially seen as sexually abhorrent. Finally, some men never intended to remain permanently in caring occupations. Their exit is driven by an ambition to pursue a career in another field or at what they view as a more challenging career level.
Analysis of agricultural pollution by flood flow impact on water quality in a reservoir using a three-dimensional water quality model
Authors: Zhang Chen , Gao Xueping , Wang Liyi , Chen Yuanyuan
Published: December 2015

This study presents the Yuqiao Reservoir Water Quality Model (YRWQM), a three-dimensional hydrodynamic and water quality model of the Yuqiao reservoir, China. The YRWQM was developed under the environmental fluid dynamics code (EFDC) model and was calibrated and verified to hydrodynamic and water quality data, using two sets of observed data from January 1 to December 31, 2006 and from May 1 to October 31, 2007, respectively. The primary hydrodynamic and transport driving forces are inflows/outflows and surface wind stresses. Considering effects of water transfer and wind on the advection-dispersion processes, the model results showed better agreements with observed data in the reservoir. The YRWQM predicted the variations of water quality resulting from agricultural pollution which flowed into the reservoir with floods lasting for 12 days in 2009. The results indicated that the concentrations of chemical oxygen demand and total nitrogen were increased 225 and 314%, respectively. Considering the interactions between chlorophyll-a and nitrogen in the model, the results indicated the reservoir was not a nitrogen-limited environment. We suggest the management should focus on agricultural pollution strategies for the reservoir during the flood period. The YRWQM could be a useful tool for water sources management in the reservoir.
Evaluation and application of Fuzzy Differential Evolution approach for benchmark optimization and reservoir operation problems
Authors: Vucetic Dejan , Simonovic Slobodan P.
Published: December 2015

The differential evolution (DE) algorithm is a powerful search technique for solving global optimization problems over continuous space. The search initialization for this algorithm is handled stochastically and therefore does not adequately capture vague preliminary knowledge. This paper proposes a novel Fuzzy Differential Evolution (FDE) algorithm, as an alternative approach, where the vague information on the search space can be represented and used to deliver a more focused search. The proposed FDE algorithm utilizes (a) fuzzy numbers to represent vague knowledge and (b) random alpha-cut levels for the search initialization. The alpha-cut intervals created during the initialization are used for fuzzy interval based mutation in successive search iterations. Four benchmark functions are used to demonstrate performance of the new FDE and its practical value. Additionally, the application of the FDE algorithm is illustrated through a reservoir operation case study problem. The new algorithm shows faster convergence in most of these functions.
Modeling impacts of highly regulated inflow on thermal regime and water age in a shallow reservoir
Authors: Wu Binbin , Wang Guoqiang , Liu Changming , Xu Zongxue
Published: December 2015

Thermal regime and transport of dissolved pollutants, strongly related to water quality and algae bloom in reservoirs, may be quantized by indicators of water temperature and water age, respectively, and these indicators are more spatially and temporally variant in shallow reservoirs. Here, a two-dimensional model was used for studying characteristics of the indicators in Douhe Reservoir, based on data of the year 2008. Douhe Reservoir is a typical shallow reservoir in Northern China, characterized by highly regulated inflow and thermal effluent. The impacts of the regulated inflow on reservoir thermal regime and water age were then analyzed through numerical experiments. The results show that the effects of inflow are associated with the flow circulations induced by inflow, thermal effluent, and wind. The most efficient inflows for alleviating thermal pollution and improving water exchange are 32.5 and 19.5 m3/s, respectively. A positive logarithmic correlation is found between water temperature and water age under the impact of inflow, while thermal effluent and wind have a slightly negative effect on the correlation. These findings provide useful information for better understanding the complex hydrodynamic and mass transport processes in a shallow reservoir.
RainIDF: automated derivation of rainfall intensity–duration–frequency relationship from annual maxima and partial duration series
Authors: Chang Kian Boon , Lai Sai Hin , Faridah Othman
Published: December 2015

RainIDF, a software tool for derivation of rainfall intensity–duration–frequency (IDF) relationship is developed as an Excel add-in by using Visual Basics for Applications (VBA). The tool is integrated with two of the most widely used statistical distributions for determination of IDF relationship: the generalized extreme value (GEV) distribution for annual maxima series, and the generalized Pareto (GPA) distribution for partial duration series (PDS). It provides automated distribution fitting for rainfall data in the form of annual maxima or PDS for multiple intervals, solving and plotting of rainfall IDF curves. RainIDF uses the Solver add-in function in Excel to solve the coefficients of the empirical IDF formula in one step. The methodology built into RainIDF is discussed and rainfall IDF relationships for several stations in Peninsular Malaysia are derived and compared. RainIDF is available for download on GitHub (http://github.com/kbchang/rainidf) as an Excel add-in.
Predicting peak breach discharge due to embankment dam failure
Authors: Duricic Jasna , Erdik Tarkan , van Gelder Pieter
Published: December 2015

Predicting peak breach discharge due to embankment dam failure is of vital importance for dam failure prevention and mitigation. Because, when dams fail, property damage is certain, but loss of life can vary depending on flood area and population. Many parametric breach models based on regression techniques have been developed so far. In this study, an efficient model is proposed to forecast peak discharge from the height of the water and volume of water behind the dam at failure, respectively, by using the Kriging approach. The previous studies, which consist of 13 numerical models, are used as a benchmark for testing the proposed new model, by employing five different error criteria. Moreover, a new database is compiled by extending the previous one. In addition, it is demonstrated that R2, which only quantifies the dispersion between measurements and predictions, should not be considered alone for checking the model capabilities. At least, the other criteria should be employed together with R2. As a result, it is shown that one can forecast the peak flow discharge with more significant accuracy by the proposed model than other previous models developed so far.
Spatial variations of river–groundwater interactions from upstream mountain to midstream oasis and downstream desert in Heihe River basin, China
Authors: Cai Yi , Huang Wenrui , Teng Fei , Wang Beibei , Ni Ke , Zheng Chunmiao
Published: December 2015

The Heihe River basin consists of three different characteristic regions: upstream mountain area, midstream oasis region, and downstream desert region. Understanding the river–groundwater interactions in different river reaches is important for sustainable water resources management. In this study, river–groundwater interactions in three different river regions are investigated by the analysis of geophysical characteristics, meteor-hydrological characteristics, agricultural irrigations, and channel water balance equation in the river reaches in different seasons. Results indicate that the river–groundwater interactions vary geographically in the three different regions, and change seasonally with the strongest interactions during the summer. Groundwater discharges into the river in the upstream mountainous reach (annual 2.57 × 108m3) while the river water seeps into aquifers in the downstream desert reach (annual 10.39 × 108m3). In the midstream oasis region, pumping water for agriculture irrigation significantly affects the river–groundwater interaction. The river loses water to the ground during the major- and medium-irrigation periods, and gains water from groundwater during the minor-irrigation period in the midstream reach. The characteristics of the river–groundwater interactions are primarily dominated by physiographic features and precipitation in the upstream mountainous region, by human activities and precipitation in the midstream oasis region, and by evaporation and human activities in the downstream desert region.
Stochastic simulation of daily streamflow sequences using a hidden Markov model
Authors: Pender Douglas , Patidar Sandhya , Pender Gareth , Haynes Heather
Published: December 2015

Estimation of daily streamflow time series is of paramount importance for the design and implementation of river engineering and management projects (e.g., restoration, sediment-transport modelling, hydropower). Traditionally, indirect approaches combining stochastic simulation of rainfall with hydrological rainfall–runoff models are used. However, these are limited by uncertainties in model calibration and computational expense. Thus, this paper demonstrates an alternative, direct approach, for stochastic modelling of daily streamflow data, specifically seeking to address well-known deficiencies in model capability to capture extreme flow events in the simulated time series. Combinations of a hidden Markov model (HMM) with the generalised extreme value (HMM-GEV) and generalised Pareto (HMM-GP) distributions were tested for four hydrologically contrasting catchments in the UK (Rivers Dee, Falloch, Caldew and Lud), with results compared to recorded flow data and estimations obtained from a simpler autoregressive-moving-average (ARMA) model. Results show that the HMM-GP method is superior in performance over alternative approaches (relative mean absolute differences (RMAD) of <2% across all catchments), appropriately captures extreme events and is generically applicable across a range of hydrological regimes. In contrast, the ARMA model was unable to capture the flow regime successfully (average RMAD of 14% across all catchments).
A model for the snow water equivalent derived from stratigraphy observations in northern Sweden
Authors: Johansson Cecilia , Ingvander Susanne
Published: December 2015

A new parameterization of snow water equivalent (SWE) based on snow depth (HS) has been developed from observations made in northern Sweden. When applying previous SWE parameterization from the Alps on observations from northern Sweden, the SWE values are systematically 20% lower. The new SWE parameterization is derived from a snow layer density regression model using snow layer hardness and snow particle size. The model was evaluated with a detailed field reference dataset, and then applied to the long-term Abisko Scientific Research Station stratigraphic snowpack dataset. The model enables a regional adjustment of snow layer density values for northern Swedish conditions. The snow layer density model provides an accurate estimation of snow bulk density used to derive the SWE parameterization based solely on HS. Snow depth observations are made on a daily basis; by applying our new parameterization, daily values of SWE can be obtained for northern Scandinavian conditions, which can be used, for example, for hydropower production planning and risk assessments.
Assessing the impact of climate change on water resources, crop production and land degradation in a semi-arid river basin
Authors: Emam Ammar Rafiei , Kappas Martin , Hosseini Seyed Zeynalabedin
Published: December 2015

The semi-arid regions of Iran have experienced severe water resources stress due to natural (e.g., drought) and anthropogenic (e.g., depletion of water in various sectors) factors. Assessing the impact of climate change on water resources and crop production could significantly help toward better water management and hence prevention of land degradation in this area. A hydrological model of the Razan–Ghahavand basin was used as a representative case study of a semi-arid region of Iran. Future climate scenarios in the mid-21st century were generated from four global circulation models (GCMs) with three scenarios under the fourth assessment report of Intergovernmental Panel on Climate Change emission projections. The GCMs have been downscaled based on observed data at 10 climate stations across the basin. The results showed that for the basin as a whole, the mean annual precipitation is likely to decrease while the maximum temperature increases. The changes in these two climate variables resulted in substantial reduction in groundwater recharge as the main source of water supply in this area. Furthermore, soil water content was decreased which resulted in the reduction of crop yield in rain-fed areas. Indeed, the risk of drought in the south and flooding in the north was high.
Spatio-temporal variability in the thermal regimes of the Danjiangkou reservoir and its downstream river due to the large water diversion project system in central China
Authors: Chen Pan , Li Lan , Zhang Hongbin
Published: December 2015

Understanding water temperature variation in regulated rivers and reservoirs becomes increasingly important as the environment and ecosystem are approaching their thermal limits. In this paper, a multi-model approach is used to quantitatively access the spatio-temporal change in thermal structures of the Danjiangkou reservoir and its downstream river. The area is subject to thermal and hydrological alterations due to three large water diversion projects and related auxiliary projects, including a project to heighten the Danjiangkou dam and two small downstream reservoirs. It is found that the Danjiangkou dam heightening project alters water temperature seasonally, increasing it in winter and decreasing it in summer; while the three large water diversion projects and the two small downstream reservoirs mitigate the effect. Water temperature change in the downstream river is also studied from the aspects of release temperature and release discharge of the Danjiangkou reservoir. The former mainly changes the water temperature near the dam, while the latter affects the recovery rate and the recuperation distance. Ecological impact of the water temperature change is discussed based on the spawning of fish, indicating that the spawning periods may lag behind and the optimal spawning locations may move downstream.
Quantitative assessment of the impacts of irrigation on surface water fluxes in the Tarim River, China
Authors: Hao Zhenchun , Chen Sichun , Li Zehua , Yu Zhongbo , Shao Quanxi , Yuan Fei , Shi Fangxin
Published: December 2015

Irrigation is a significant human activity that affects surface water fluxes in the Tarim River Basin. To quantitatively assess the irrigation impact of this activity on surface water fluxes in the Tarim River, a land surface hydrologic model was coupled with a modified irrigation scheme and a reservoir module and applied to simulate these fluxes. Modeling results indicate that the combined effect of the irrigation process and reservoir operation is prominent in the study area, from which 70–75% of the surface water is extracted and used for irrigation. This scenario can primarily be attributed to the significant amount of water losses as a result of evaporation and the seepage of canals and aqueducts. The effective utilization coefficient of the extracted surface water is only approximately 0.40. The irrigation water withdrawals increased with the recent rapid expansion of cultivated land. Therefore, the water flowing into the main stem of the Tarim River still shows a downward trend, despite the significant increase in the total discharge of headwater basins since the 1960s.
The impact of climate changes on water level of Qinghai Lake in China over the past 50 years
Authors: Cui Bu-Li , Li Xiao-Yan
Published: December 2015

Understanding the variation regularity of lake level and the potential driver factors can provide insights into lake conservation and management. In this study, inter- and inner-annual variations of lake level in Qinghai Lake during the period 1961–2012 were analyzed to determine whether climatic factor or runoff factor were responsible for the variations. The results showed that lake level decreased significantly during the period 1961–2004 at a rate of −7.6 cm/yr, while increasing significantly during the period 2004–2012 at a rate of 14 cm/yr, and all were significant at a p value of <0.01. Lake level was most sensitive to climate and river runoff. Precipitation and river runoff had directly positive effects on lake level, but inverse evaporation and wind speed played a significantly negative role on lake level. The relative contributions of influencing factors in the Southeast Asian monsoon (SEAM) and the westerly circulation periods on annual lake level variations were approximately 49.8% and 27.8%, respectively. The relative contributions of temperature, precipitation, evaporation, and wind speed on lake level variation were approximately 13.8%, 36.3%, 27.1%, and 18.4%, respectively. In general, the annual lake level was primarily influenced by precipitation and evaporation of the SEAM period.
Achieving sustainable water supply through better institutions, design innovations and Water Safety Plans – an experience from Nepal
Authors: White Pamela , Badu Indra Raj , Shrestha Parikshit
Published: December 2015

Sustainable functionality of rural water infrastructures is a major challenge in Nepal, as elsewhere. This paper looks at systems for improved community-based water supply and sanitation management in the Rural Village Water Resources Management Project (RVWRMP), in mid and far west Nepal. The paper analysed 496 rural, community-managed drinking water and sanitation schemes (with 30 to 250 beneficiary households per scheme) supported by RVWRMP (2006–2014). Observed results are: 91.5% fully functional, 8.3% partially functional and 0.2% of schemes closed due to natural disasters and social conflicts. This compares very favourably to the systems implemented by the government of similar age. We consider that the experience gained in RVWRMP provides relevant lessons on how to safeguard the functionality of rural water services infrastructure systems. The key elements noted by our staff are: prioritisation of the schemes by the community; application of quality implementation and user committee management; Water Safety Plans and active maintenance; and hands-on technical support and monitoring.
Application of nano-silver coated granular activated carbon for inactivation of septic tank effluent
Authors: Koottatep Thammarat , Chapagain Saroj Kumar , Watanatanachart Jaruwat , Polprasert Chongrak
Published: December 2015

On-site sanitation systems such as cesspools and septic tanks are widely used in most developing countries. These systems primarily aim to collect and treat toilet wastewater or blackwater. Although septic tanks are commonly used in non-sewered areas, their effluents are still rich in pathogens and other pollutants. The practice of direct discharge of septic tank effluents into the surrounding environment in the absence of proper treatment has increased health risks. In order to reduce this problem, a post-treatment unit consisting of nano-silver coated granular activated carbon (NS-GAC) has been developed. The study results revealed that the inactivation efficiency of the NS-GAC unit increased with increasing hydraulic retention times (HRT) from 10, 20 and 30 minutes; however, for economy of scale, the NS-GAC unit could be operated at the 10 minutes HRT to achieve complete removal of Escherichia coli bacteria. The study showed a high feasibility of utilizing the NS-GAC media as a post-treatment unit for pathogen inactivation of septic tank effluent.
Willingness to pay for VIP latrines in rural Senegal
Authors: Hall Ralph P. , Vance Eric A. , Van Houweling Emily , Huang Wandi
Published: December 2015

In 2015, African ministers established the Ngor Declaration to achieve universal access to adequate sanitation and hygiene services and eliminate open defecation by 2030. Realizing this target will require significant public and private investment. Over the last two decades, there has been increasing recognition that sanitation programs should be demand driven, yet limited information exists about how much rural residents in developing countries are willing to pay for sanitation improvements. This paper applies the contingent valuation approach to evaluate how much households in rural Senegal are willing to pay for a ventilated improved pit (VIP) latrine. The analysis uses data from 1,635 household surveys that were conducted in 47 rural communities across four regions in Senegal. The willingness to pay model found that respondents were more willing to pay for a VIP latrine if they had plans to improve their existing latrine, lived in districts located nearer to the capital city of Dakar, were dissatisfied with their existing sanitation service, and were male. The analysis also indicates that the current household contribution of 5% of the costs of constructing a VIP latrine could be increased to 30% with only a modest decline in the number of households willing to pay this amount.
Analysis of institutional arrangement for greywater management in unplanned settlements of Kinondoni municipality Tanzania
Authors: Ndunguru Teresia W. , Mulungu Deogratias M. M.
Published: December 2015

Greywater (GW) may contain pathogens and organics thereby calling for its management. Institutional arrangement (IA) is the heart of planning, coordination and management of initiatives. Analysis of IA is key for determination of what could be rectified within organisations based on the existing structure, resources, strategies, data and information, stakeholder participation and involvement, policy and by-laws. Kinondoni municipality has the largest population of the three municipalities in Dar es Salaam city. In this study, the IA for GW management in Kinondoni municipality was analysed using weighted strengths, weaknesses, opportunities and threats (SWOT). The weights for the SWOT criteria were obtained from field interviews with households and key informants, and then integrated using expert judgement. Overall, from the analysis matrix, the SWOT was towards weaknesses (73%) and opportunities (60%). Weaknesses were largely due to internal factors, others were lack of horizontal and vertical coordination, accountability, and stakeholder participation. With respect to GW management, these results revealed that there is inadequacy in the existing institutional structure, which accelerates poor performance in GW management practices in Kinondoni municipality. Accordingly, this study proposed an IA that induces stakeholder involvement and participation, accountability mechanisms and collaboration between departments in GW management.
On-site treatment of used wash-water using biologically activated membrane bioreactors operated at different solids retention times
Authors: Ravndal Kristin T. , Künzle Rahel , Derlon Nicolas , Morgenroth Eberhard
Published: December 2015

Biologically activated membrane bioreactors (BAMBis) were operated at suspended solids retention times (SRT) of 7 and 102 days and at full solids retention. The effect of these different approaches of operation on the substrate and nutrient conversion, and on permeate flux, was investigated. Variations in organic loads and aeration intensities were also studied. Permeate flux stabilized during long-term operation independently of suspended SRT. Removal of the organic substrate was independent of solids concentrations and remained stable over the long term. Microorganisms colonizing the surface of particles were found to be the main mechanism responsible for degradation of the organic substrate in the particulate form. BAMBi appeared to be a robust technology, adapted to on-site treatment of used wash-water, as it can be operated without control of suspended SRT. Thus BAMBis can be operated for long periods without any control of biofouling and sludge formation, leading to low maintenance needs. When BAMBis were operated at low aeration, the formation of anoxic zones led to combined nitrification and denitrification and thus significant nitrogen removal.