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In this work, an analysis of the energy vanished by friction of thin-walled tube drawing processes in conical converging dies with a fixed conical inner plug has been conducted. The method used for analysis is the upper bound method (UBM), and the plastic deformation zone has been modelled by three triangular rigid zones (TRZ). The tube inner diameter is considered constant during the process, and therefore, a state of plane strain can be assumed. In addition, the existent friction between the external surface of the tube and the die (material-die), as well as that between the inner surface of the tube and the plug (material-plug) has been modeled by Coulomb friction (μ1 and μ2, respectively). Some significant findings emerged from this study are: the establishment of explicit expressions for evaluating the non-dimensional energy vanished by friction in the die and in the plug, the ability to select the plug that enables the process to be performed with a lower requirement of energy under defined conditio...

Agile manufacturing systems work in a constantly changing global market, particularly assembly systems at the last stage of product differentiation. Meanwhile, sustainability is becoming a key issue for manufacturing strategy. This paper formulates a systemic criterion of sustainability in agile manufacturing and computes it through flexibility and complexity. It is defined as a ratio of utility and entropy as a sustainability measurement. Under a unified framework, utility allows one to quantify the contributions to agility, in particular system flexibility. Complexity is measured by entropy. Thus, an original complementary role of flexibility and the complexity of the system are proposed. Developed from the distribution of system states, the systemic approach to sustainability in terms of output evolution is enriched. Based on a simple assembly line integer model simulation, a first quantitative analysis illustrates the concepts introduced.

Manufacturing flexibility is becoming a fundamental production objective, along with cost, quality, and delivery time. Current production systems face quick changes in market conditions and they need to adapt in this environment. The supply chain and industrial globalization give an important role for assembly systems. Placed at the end of the value chain, assembly systems must face those quick changes successfully to reach the expected performance. The key performance indicators are normally based on cost, quality, and delivery time objectives. Reducing costs and improving quality are almost universal goals. Delivery time is typically determined by customer demand in the supply chain, planning from make-to-stock to make-to-order, and aspiring to reach a just-in-time manufacturing system. In this context, flexibility could be the differential advantage to tackle uncertainty. Closely related to the rest of production objectives and the overall performance of the system, flexibility must be integrated in the system for successful decision-making in operations. This work presents this approach of flexibility. A brief review of flexibility concepts and measurements in the literature precedes an introduction to flexibility, defined based on the function of utility. This function represents the expectations of system performance. This approach allows the formulation of the taxonomy of operational flexibility in agreement with the classical types identified in former works. Next, an integer model is programmed to simulate the basic behavior of task planning in a make-to-order assembly system. This first application illustrates flexibility quantification based on utility evolution. The use of common industrial parameters to quantify operational flexibility will finally facilitate an integrated interpretation of system performance trends.

Besides traditional occupational risks, advanced manufacturing processes (AMP) can generate other risks described by the Eu ropean Agency for Safety and Health at Work (EU-OSHA) as “new and emerging risks” (NER) to occupational safety and h ealth. Several studies have been carried out by the EU-OSHA in order to identify all these risks. However, the direct use of this set of NER in identification procedures of occupational risks, generally applied in labour p rocesses and particularly in AMP, may result in the identification of traditional occupational risks rather than NER, mainly because they have been defined without following a risk reference model. To solve this problem a risk model has been developed that improves and complements the NER definition of EU-OSHA, from w hich a second model has been developed to analyze the structure of the considered set of NER. It is observed that with the results obtained, the current descriptions of these NER do not explain their quality of "new and "emerging". © 2015 The Authors. Published by Elsevier Ltd. Peer-review under responsibility of DAAAM International Vienna.

This work is developed in the teaching context of the subject “Technological Aspects of Safety” (ATS) as part of the University Master's Degree in Occupational Safety and Health (OSH) of the National University of Distance Education (UNED). A classification of Industrial Safety Technologies, grouped in ATS, has been developed that links basic rules applicable to the technical guides (TG) and Technical Notes Prevention (NTP) of the National Institute of Safety and Health at Work (INSHT). The TG are essential tools for the technical interpretation of associated regulations, as their updates are generally adequate, not so for the NTP, especially considering that 54% of those analyzed predate 1997 (beginning of basic regulatory development). However, the characteristics of the classification aids the design of teaching activities, focused on the analysis and knowledge of the industrial safety technologies.

En septiembre de 2000, durante la Cumbre del Milenio de las Naciones Unidas, 147 jefes de estado adoptaron las Metas de Desarrollo del Milenio (MDM) con la intención de reflejar sus compromisos con el desarrollo global y la reducción de la pobreza. En 2002, el Programa para el Desarrollo de las Naciones Unidas estableció el Proyecto del Milenio de las Naciones Unidas, mediante el cual se establecieron 13 grupos de trabajo para identificar estrategias y medios de implementación que permitieran alcanzar cada uno de los objetivos de las MDM. Se creó el Grupo de Estudio sobre el Comercio para la MDM 8, con vistas a desarrollar una asociación global para el desarrollo. El objetivo de este artículo es examinar las principales recomendaciones en política comercial como estrategia para alcanzar las MDM relacionadas con la salud en América Latina. En este artículo se cuestiona la propuesta del informe de ese Grupo de Estudio de promover el "libre" comercio en los países desarrollados y en desarrollo y la liberalización de los servios de salud. También se analizan las implicaciones del Acuerdo General sobre el Comercio de Servicios (AGCS) para los sistemas de salud en América Latina. Se concluye con un llamado de alerta en relación al AGCS y se hace hincapié en la necesidad de un comercio genuinamente más justo para alcanzar las MDM en América Latina.

In this work, an energetic analysis of thin-walled tube drawing processes in conical converging dies with inner plugs has been made. The method used in the analysis is the upper bound method (UBM). The plastic deformation zone has been modelled by triangular rigid zones (TRZ), with the assumption that the process occurs under plane strain and Coulomb friction conditions.

Equal channel angular extrusion or pressing (ECAE or ECAP) is a process used in order to impart severe plastic deformations to processed materials with the aim of improving their mechanical properties by reducing the grain size. The grain size reduction leads to mechanical properties improvement. In the present study, a new die configuration is proposed for the ECAE process. The advantage of this die geometry is that it allows us to obtain higher plastic strain in each ECAE passage than traditional ECAE dies. It is important to optimize the die geometry, as the main aim of the ECAE process is to impart severe plastic deformations to the processed materials. Consequently, the higher the deformation, the better the improvement on the mechanical properties of the processed materials. In order to determine how variations on geometry affect the plastic strain of the processed materials finite element modeling (FEM) is used. Both analytical and FEM methods will allow us to affirm that by using this new die configuration it is possible to achieve higher deformation values per ECAE passage.

En este artículo se estudia el proceso de taladrado sin fluido de corte, de la aleación Ti6A14V, comparando dos condiciones de mecanizado, con y sin enfriamiento de herramienta y material entre taladros. El objetivo de este trabajo es analizar la influencia en el desgaste de la herramienta y en la calidad del agujero, del diferente incremento de temperatura originado por trabajar en una u otra condición. Para ello, se realizará análisis SEM/EDS y microscopía óptica de la broca e inspección visual del material. This paper is focused on dry drilling of Ti6Al4V. In absence of cutting fluid, high temperatures are reached. Two different cutting conditions are studied in order to analyse the influence of temperature. In first condition, tests with no pause between drilled holes were carried out. In second condition, tests were performed cooling the tool with air between consecutively holes. Tool wear was studied with optical microscope and SEM-EDS techniques. The quality of machined holes was estimated in terms of optical inspection. Significantly differences in tool wear evolution were observed between both cutting conditions analysed. Este trabajo ha sido financiado por la Comisión Interministerial de Ciencia y Tecnología (CICYT) proyecto DPI2001-3747, por AIRBUS España, S.L. y por la Junta de Andalucía. Los autores agrádecen al Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica de la Universidad Carlos III de Madrid su ayuda y la disponibilidad de sus equipos para la realización de los estudios de microscopía óptica y SEM/EDS. Publicado

Virtual reality (VR) is a very helpful and valuable work tool for the simulation of manufacturing systems. It can be used in both industrial and academic/researcher fields allowing the system's behaviour to be learnt and tested. VR provides a low-cost, secure and fast analysis tool. It also provides benefits, which can be reached with many different system configurations. The work presented in this paper reviews some of the most recent developments that have been made in this way and proposes a general methodology for the creation of virtual environments applicable to manufacturing systems. The application samples of this procedure are focused on flexible manufacturing systems (FMS), in which the economic and safety problems are heightened.

We are moving away from the year 2000, and the goal of "health for all" remains distant. Economic globalization, which many consider to be one of the most serious threats to health, moves ahead, along with globalization of international health policies. A small number of powerful actors are in charge of setting the agenda, and they relegate to an inferior position the World Health Organization, which has moved away from the goal of "health for all." All of this has helped to promote a neoliberal mentality in the field of health. The People's Health Movement was created with the objective of reestablishing the right to comprehensive health and to development with equity as principal priorities of health policies at the local, national, and international levels. The People's Health Movement uses as a strategy the People's Charter for Health, which was approved at the first People's Health Assembly, which was held in Bangladesh in 2000. The Charter expresses collective concerns and the belief in a better and healthier world as a meeting point in order to promote a world health movement and a call for radical action. In July 2005 the People's Health Movement will hold the People's Health Assembly 2, in the city of Cuenca, Ecuador. The slogan of that meeting will be "The voices of the earth are calling!-let's build a healthy world." Among the topics that will be examined at the meeting are: health as a fundamental human right; militarization and occupation; environmental degradation; emerging and reemerging pandemics; equity, poverty, and health; the importance of cultural diversity; social and political violence; health in the hands of the people; health at work; traditional medicine and bioenergetic medicine; gender; and health sector reform. The objective of the People's Health Movement is to help to reach the Millennium Development Goals and to smooth the path toward attaining health for all, in Latin America and the Caribbean as well as in the rest of the world.

In this work, scanning electron microscopy has been used in order to identify the effects of adhesion on the dry turning processes of different aerospace aluminium alloys. Analysis with energy dispersive spectroscopy allows distinguishing different composition characteristics between built-up layer (BUL) and built-up edge (BUE) formation in the processes we studied. A preliminary hypothesis on the formation of BUL and BUE, taking into consideration the temperature in the region of initial deformation has been formulated. According to this hypothesis, BUL formation is preceded by a process of incipient fusion, which releases intermetallic particles. Once BUL has formed initial cutting conditions change enabling BUE formation by mechanical adhesion. Additionally, the evolution of BUL and BUE with the time of machining has been also studied.

Drawing process is one of the most used metalforming process within the industrial field, particularly, in automotive and electric sectors. Then, different analytical, numerical, empirical and experimental methods have been developed in order to analyse it and to optimise it. However, exact solutions have not achieved yet due to the great number of factors involved in this type of processes and to the mathematical complexity that they present. In this work, the main variants of the drawing process have been studied by different methods. Concretely, wire drawing and plate drawing have been modelled and simulated by means of the slab method (SM) and finite element method (FEM). In addition, the results obtained in both cases have been compared with other solutions found in the literature about these themes, particularly, with Wistreich’s solutions in wire case and with Green and Hill and the upper bound technique ones in plate drawing case. © 2005 Elsevier B.V. All rights reserved.

OBJECTIVE: To provide some of the first data on cancer incidence among indigenous people in the Amazon basin of Ecuador, and to compare that incidence with the level found among nonindigenous persons living in that same area. METHODS: From the study area 1 207 cancer cases were reported to the National Cancer Registry over the 1985-2000 period. Frequency and relative risks were calculated for the indigenous residents and for the nonindigenous residents of the area. RESULTS: Cancer of the testes and leukemia were the most common cancer types among indigenous men, and cancer of the cervix uteri was the most common among indigenous women. Indigenous men were at significantly lower risk for cancer of the stomach, skin, prostate, and lymph nodes and for leukemia than were nonindigenous men. Indigenous women were at significantly lower risk for cancer of the stomach, skin, breast, cervix uteri, and lymph nodes than were nonindigenous women. CONCLUSION: Our data from the Ecuadorian Amazon indicate the need to develop appropriate mechanisms to register the indigenous population in the national census as well as in the National Cancer Registry. Also needed are cancer early detection programs, more health education efforts, and stronger health services that are adapted to the local conditions. Future research should focus on factors that may help to explain the different cancer patterns found among indigenous persons and nonindigenous persons.OBJETIVO: Proporcionar los primeros datos sobre la incidencia de cáncer en la población indígena de la cuenca amazónica del Ecuador y comparar dicha incidencia con la hallada en la población no indígena que habita en la misma zona. MÉTODOS: En la zona estudiada se notificaron 1 207 casos de cáncer al Registro Nacional de Cáncer en el período de 1985-2000. Se calcularon las respectivas frecuencias y riegos relativos de los residentes indígenas del territorio y de los residentes no indígenas. RESULTADOS: El cáncer testicular y la leucemia fueron los cánceres más comunes en los hombres de raza indígena, y el cáncer de cuello uterino fue el más frecuente en las mujeres de esa raza. Los hombres indígenas tuvieron un riesgo menor de cáncer de estómago, piel y próstata, así como de linfomas y leucemias, que los hombres de raza no indígena. Las mujeres indígenas también mostraron un riesgo menor de cáncer de estómago, piel, mama y cuello uterino, así como de linfomas y leucemias, que las mujeres no indígenas. En ambos casos las diferencias entre una raza y otra fueron estadísticamente significativas. CONCLUSIÓN: Nuestros datos obtenidos en la cuenca amazónica del Ecuador apuntan a la necesidad de crear mecanismos adecuados para inscribir a la población indígena en el censo nacional y en el Registro Nacional de Cáncer. También hacen falta programas para la detección temprana del cáncer, nuevas iniciativas de educación sanitaria y mejores servicios de salud adaptados a las condiciones locales. Las investigaciones realizadas en un futuro deberán centrarse en aquellos factores que podrían explicar las diferencias en la frecuencia de distintos cánceres en personas indígenas y no indígenas.

Gracias a los tratados comerciales internacionales, el comercio mundial y la inversión extranjera se han incrementado vertiginosamente en los últimos 25 años. Es preciso, entonces, examinar las pruebas acumuladas de que el comercio tiene un efecto sobre la salud e incorporarlas en el proceso de formulación de políticas. Uno de los acuerdos en actual proceso de negociación es el Área de Libre Comercio de las Américas (Free Trade Agreement of the Americas,o ALCA). Con el fin de ayudar a evaluar las posibles consecuencias sanitarias de este acuerdo en el Hemisferio Occidental, este artículo examina los 10 años de experiencia que han tenido Canadá, México y los Estados Unidos de América con el Tratado de Libre Comercio de América del Norte (North American Free Trade Agreement,o TLCAN). Aunque los tres países han visto una expansión macroeconómica, las ganancias prometidas en lo referente a mayores fuentes de empleo, mayores ingresos y menos desigualdad y pobreza no se han producido. El TLCAN también ha tenido un gran impacto en la agricultura, los servicios públicos y el grado de soberanía ejercido por los tres gobiernos en lo que respecta a la adopción de políticas en pro de los intereses del público. Se espera que el ALCA sea el régimen de comercio e inversión más completo del mundo. Representa un mayor peligro que el TLCAN debido a la vulnerabilidad de la mayoría de los países de las Américas y a la propuesta de que se incorporen al ALCA nuevos reglamentos muy estrictos encaminados a extender la injerencia del tratado hacia nuevos sectores que el TLCAN no abarca. Las organizaciones de salud pública deben participar en la polémica en torno al ALCA y los gobiernos de los países de las Américas deben darle mayor prioridad a la salud que al comercio si se han de evitar riesgos innecesarios para la salud de los pueblos americanos.

The design and manufacturing of hot forged parts, using proposed of feasibility and optimization approaches that, based on technico-economics considerations, allow to evaluate numerically the rate of adaptation of the different morphologies at the forging process, is analyzed in this work. The integration of these approaches in an unique global adaptation coefficient, carried out considering the technical and economic importance of each factor, facilitates the selection of the best alternative. Also, the use of this coefficient allows, in studies of general nature, to make quantitative classifications of the analyzed parts, in studies facilitating a hierarchical order of the different alternatives, when groups and sub-groups according to characteristic parameters of each family, are established.

OBJETIVOS: Evaluar el estado nutricional de los niños indígenas naporunas menores de 5 años de la región amazónica del Ecuador e identificar los factores de riesgo de desnutrición que afectan a esta población. MÉTODOS: Se realizó un estudio transversal en la provincia de Orellana, al nordeste del Ecuador, entre junio de 2001 y febrero de 2002. Se realizaron entrevistas domiciliarias en 30 comunidades elegidas al azar y se aplicó un cuestionario que recogió los datos sociodemográficos y de paridad de las madres de niños menores de 5 años, así como los datos demográficos y antropométricos de los niños, la historia de su lactancia y las enfermedades que ellos padecieron en las dos semanas previas a la encuesta. Se realizó también un examen clínico a cada niño. El diagnóstico de anemia fue clínico y se basó en el examen de la conjuntiva ocular. La asociación estadística entre las diferentes variables se determinó mediante la prueba de la ji al cuadrado, y se emplearon la corrección de Yates y la prueba exacta de Fisher de dos colas cuando el número de observaciones era 5 o menos. Los factores de riesgo de la desnutrición crónica y del bajo peso se identificaron mediante análisis de regresión logística. RESULTADOS: En total se entrevistó a 189 madres de 347 niños menores de 5 años. De ellos, 307 niños (88,5%) participaron en el estudio. Se observó desnutrición crónica en 22,8% de los niños, 26,4% presentaban bajo peso y 9,8% padecían de desnutrición aguda. La prevalencia de desnutrición crónica grave fue de 7,5%, la de bajo peso grave de 4,9% y la de aguda grave de 1,6%. En total, 5 (1,6%) niños presentaron indicadores de desnutrición crónica y aguda. La mayor prevalencia de desnutrición crónica se observó en el grupo de edad de 48 a 59 meses y la mayor prevalencia de bajo peso grave y de desnutrición se detectó en el grupo de 12 a 23 meses. Los factores determinantes estadísticamente significativos de desnutrición crónica fueron vivir en una comunidad sin acceso a alguna carretera, el número total de niños en la familia (> 7), y la presencia de infecciones respiratorias agudas y de distensión abdominal el día del examen. La distensión abdominal y la palidez conjuntival a la exploración física fueron los factores pronósticos en relación con el bajo peso. CONCLUSIONES: Las prevalencias de desnutrición aguda y crónica y de bajo peso encontradas en niños naporunas menores de 5 años son más elevadas que las observadas en otras poblaciones amazónicas. Se requieren estudios adicionales que determinen la prevalencia de parasitosis y anemia y que evalúen las costumbres alimentarias y el tipo de dieta de las comunidades indígenas para obtener un cuadro más completo de su situación nutricional. Se recomienda poner en marcha un plan de monitoreo dirigido a evaluar las tendencias nutricionales de esta población.OBJECTIVES: To assess the nutritional status of Naporuna children under five years of age from the Amazon region of Ecuador, and to identify risk factors for developing malnutrition in this population group. METHODS: A survey-based cross-sectional study was carried out in Orellana, a province in northeastern Ecuador, between June 2001 and February 2002. Household interviews were conducted in 30 communities chosen at random, and a questionnaire was used to record the following: the social and demographic characteristics and parity of mothers having children under five years of age, and the children's demographic and anthropometric characteristics, history of breastfeeding, and medical conditions suffered over the two-week period just prior to the survey. Each child was also subjected to a physical examination. Anemia was diagnosed clinically by conjunctival exam. The statistical association among variables was determined by means of the chi-square test, with use of Yates' correction and Fisher's exact test (two-tailed) when there were 5 observations or less. Risk factors for chronic malnutrition and underweight were determined by means of logistic regression. RESULTS: Overall, 189 mothers of 347 children under five were interviewed. Of these 347 children, 307 (88.5%) participated in the study. Chronic malnutrition was found in 22.8% of the children; 26.4% were underweight, and 9.8% had acute malnutrition. Moreover, 7.5% had severe chronic malnutrition; 4.9% were severely underweight, and 1.6% had severe acute malnutrition. A total of 5 children (1.6%) showed signs of both chronic and acute malnutrition. The largest prevalence of chronic malnutrition was found in the 12-23 month age group. Risk factors for chronic malnutrition that were statistically significant included living in an area without access to a road, the total number of children in the family (>7), and the presence of an acute respiratory infection or abdominal distension on the day the physical examination was performed. Abdominal distension and pale conjunctiva on physical examination were predictive for underweight. CONCLUSIONS: Among the Naporuna children under 5 years of age included in this study, the prevalences of acute malnutrition and underweight appeared to be higher than had been previously detected among other populations in the Amazon region. More studies on the prevalence of parasitic infections and anemia and on the feeding practices and dietary habits of indigenous communities are needed in order to better understand their nutritional intake. A program for monitoring the diet of indigenous peoples is necessary and should be established.

Desde la década de 1970, el petróleo ha sido una de las principales fuentes de ingresos del Ecuador y ha servido como "motor impulsor" de la economía nacional. La mayor parte del petróleo ecuatoriano se extrae en la cuenca amazónica del nordeste del país. Desde que comenzó la explotación petrolera, compañías extranjeras y la empresa petrolera estatal Petroecuador han extraído más de dos mil millones de barriles de petróleo crudo de la Amazonía ecuatoriana. A lo largo de este proceso se han liberado al medio ambiente miles de millones de galones de desechos sin tratar, gas y petróleo crudo. Este artículo analiza el impacto ambiental y sanitario provocado por el desarrollo petrolero en la región amazónica del Ecuador. Por ejemplo, el análisis del agua de varias corrientes fluviales de la localidad ha demostrado la presencia de altas concentraciones de productos químicos derivados del petróleo en las zonas petrolíferas en explotación. Los estudios epidemiológicos han encontrado un mayor riesgo de sufrir síntomas asociados con el petróleo y abortos espontáneos en las mujeres que viven en las proximidades de los campos petroleros. También se ha encontrado una incidencia excesiva de cáncer. Se necesitan intervenciones locales, nacionales e internacionales para evitar que se empeoren los efectos negativos que ejerce sobre el medio ambiente y la salud el desarrollo petrolero. Estas intervenciones deben abarcar un sistema de monitoreo y remediación ambiental, consultas a la comunidad y participación comunitaria, mecanismos para hacer cumplir las leyes que protegen el medio ambiente y la salud de la población, y cambios en las políticas comerciales dirigidos a lograr la sostenibilidad en materia ambiental y la justicia social.

The present study focuses on aspects of the surface qualities of prototypes obtained by injection techniques. The surface finish and dimensional precision of parts obtained through these manufacturing processes is often highly important. Moreover, it is important to have an estimation of the average surface roughness in order to select the operation parameters adequately. Although there are a lot of different techniques for evaluating the surface roughness, one of the most commonly employed methods for characterising roughness involves assessment of surface roughness average by means of stylus instruments. Prototype manufacturing using two different systems of multijet injection technology was carried out, modifying the manufacturing conditions for obtaining the prototypes. After parts were obtained, an experimental study of effective roughness was done. Also, a comparative study using two injection systems with different accuracy was performed in order to evaluate the capability of these rapid prototyping techniques for manufacturing parts.

This paper presents an assessment of the selection of manufacturing codes for pressure vessels. We focus on one of the most relevant approximation methods used in manufacturing calculations for pressure vessels, i.e., the unit conversions of the ASME boiler and pressure vessels (B&PV) code. To evaluate the influence of its conversions, several errors arising from the manufacturing process and measurement systems have been calculated, estimated and considered. In addition, a decision tool for manufacturing codes of pressure vessels with novel considerations based on stringency levels is presented to improve the current selection process. The general conclusion is that adjusting the pressure units is not recommendable when designing a pressure vessel due to large errors that can accumulate. Furthermore, the length conversion is only suitable for parts manufactured with maximum dimensions of five inches (125 mm).

Once manufacturing criteria have been established, a well-founded decision support system (DSS) may solve the problem of selecting the optimum set of parameters. An axiomatic approach has been used in order to quantify final part quality. The present case takes into account form errors in blanking process and an equation model that enables quality quantification through part complexity has been developed. The measurement of complexity in blanked parts may be simplified to a study of the effect of the fundamental parameter (clearance) on the form errors. In order to consider economic influences, technical cost modelling (TCM) has been implemented. With the purpose of uniting both aspects under one common criterion, a function that evaluates them in a single measuring system has been defined. Based on this function, the developed DSS integrates a formal multi-attribute decision model with a relational database. The decision model enables representation of the user’s preferences as regards decision factors. Due to the great number of parameters and variables that intervene in the system, a computerised graphical interface application has been developed allowing decision makers to compare, justify and evaluate different alternatives in a friendly environment.

The design of industrial parts is a clear example of integrative effort that, with a focus of several disciplines, requires a detailed analysis of the different scientific and technological knowledge implied in its conception and development. Inside this performance context, the present work approaches the problem of the project of hot forging parts, proposing the use of criteria of viability and optimization that, based in technical and economical considerations, allow to value the adjusting degree of various alternative to the forge process, facilitating with it the selection of the most appropriate. Fixed these bases and with object of shortening times of answer and analysis in an application corresponding to parts with revolution symmetry, a computerized system has been introduced that, taking as started data the design of the part, geometrically simulates the forge process, allowing to calculate the adaptation coefficients in those morphologing that are possible according to the criteria of viability criteria. This system also provides a graphic representation of machined part, the forged part and the finished stamp.El diseño de piezas industriales supone un claro ejemplo de esfuerzo integrador que, con un enfoque interdisciplinar, requiere un análisis detallado de los diferentes conocimientos científicos y tecnológicos implicados en su concepción y desarrollo. Dentro de este marco de actuación, el presente trabajo aborda la problemática del proyecto de piezas estampadas en caliente, proponiendo la utilización de criterios de viabilidad y optimización que, fundamentados en consideraciones técnico-económicas, permiten valorar el grado de adecuación de las diferentes alternativas al proceso de forja, facilitando con ello la selección de la más adecuada. Fijadas estas bases y con objeto de acortar tiempos de respuesta y análisis en una aplicación correspondiente a piezas axisimétricas, se ha introducido un sistema informatizado que, tomando como dato de partida el plano de mecanizado de la pieza, simula geométricamente el proceso de estampación, permitiendo calcular los coeficientes de adecuación en aquellas tipologías que son posibles según los criterios de viabilidad. Este sistema también proporciona una representación gráfica de pieza mecanizada, pieza estampada y matriz de acabado.

A school-based control program of intestinal helminths was undertaken among schoolchildren in the Low-Napo region, north-eastern Ecuador. Forty-eight percent of children were infected with one or more helminths at the first examination. The prevalence at the baseline was Ascaris 33.2% followed by hookworm 24.1% and Trichuris 6.5%. Sex was found to be a significant factor influencing the prevalence of hookworm and Trichuris. Prevalence was compared 9 months and 18 months after treatment. After 9 months, Ascaris and Trichuris prevalence had decreased but not hookworm. All of them increased after 18 months. The findings suggest that only a course of mebendazol had a minor effect on the control of helminth infections.Um programa de controle da helmintíase foi realizado entre escolares de região do Baixo-Napo, nordeste do Equador. À primeira verificação, foi constatado que quarenta e oito por cento das crianças estavam infestadas por um ou mais helmintos. As prevalências das helmintíases apresentaram a seguinte distribuição: Ascaris, 32,2%; ancilostomies, 24,1% e Trichuris, 6,5%. A variável sexo foi considerada um importante fator ligado as prevalências do ancilostomies e do Trichuris. As prevalências foram comparadas, após 9 e 18 meses. Após 9 meses, apresentaram-se diminuídas, tanto a prevalência da ascaridíase, quanto a da tricocefalíase. Entretanto, após 18 meses, a prevalência das três helmintíases apresentaram-se elevadas. Os achados sugerem que apenas um tratamento con mebendazol produz um pequeno impacto no controle da infecção por helmintos.

Malaria is reemerging in most endemic countries of South America. In Ecuador, malaria is endemic on the Pacific coast, in the inter-Andean valleys, and in the Amazon River basin. In the Lower-Napo region of northeastern Ecuador, malaria was considered eliminated in the 1970s, but the disease has reemerged in recent years. Three organizations are involved in malaria related work in the area, but they are not coordinating their efforts. This study was designed to describe the epidemiology of malaria incidence in the Lower-Napo region for the period of January 1992 through December 1995, and to determine the extent of seasonality in transmission in the area. To determine malaria incidence, data were collected for that 4-year period from the records of the three malaria-related organizations: the office of the National Center for Malaria Eradication (NCME) in the town of Coca, the district hospital in Nuevo Rocafuerte (DHNR), and an association of community health workers called Sandi Yura. Data on climatic conditions for the same period were collected from the Ecuadorian Air Force and civil aviation authorities. During the 1992-1995 period, NCME diagnosed a total of 773 malaria cases, DHNR diagnosed 485, and Sandi Yura clinically diagnosed 859. For the 4-year period, an annual parasite index of 40.4 was found with the DHNR data, 35.8 with the Sandi Yura data, and 6.2 with the NCME data. The predominant parasite in the area was Plasmodium vivax (92% of all the cases). Twenty-eight percent of the infected persons were under 10 years old. No discernible differences between the genders were found. There was also no seasonal variation among the cases. Further research is needed in order to confirm these findings and better understand malaria transmission in the region. The study highlights the need for a closer coordination among the area's malaria-control organizations so as to have an improved understanding of malaria epidemiology and to design and implement effective control strategies.La malaria está reapareciendo en la mayoría de los países endémicos de América del Sur. En el Ecuador, la enfermedad es endémica en la costa del Pacífico, en los valles de los Andes y en la cuenca del río Amazonas. En el Bajo Napo en el nordeste del Ecuador, la malaria se consideraba eliminada en los años setenta, pero la enfermedad ha vuelto a aparecer en años recientes. Aunque en la actualidad tres organismos participan en actividades antimaláricas en esa zona, sus actividades no están coordinadas. Este estudio se efectuó con el propósito de describir la epidemiología de la incidencia de malaria en el Bajo Napo durante el período de enero de 1992 a diciembre de 1995, así como de determinar hasta qué punto existen patrones estacionales en la transmisión en ese territorio. Para determinar la incidencia de malaria, se recogieron datos para el cuadrienio 1992-1995 a partir de los registros de los tres organismos con actividades antimaláricas: la sede del Servicio Nacional de Erradicación de la Malaria (SNEM) en Coca, el hospital de distrito de Nuevo Rocafuerte (HDNR) y una asociación de trabajadores de salud comunitarios llamada Sandi Yura. La información climatológica para el mismo período se obtuvo de la Fuerza Aérea Ecuatoriana y de las autoridades de aviación civil. Durante el período de 1992 a 1995, el SNEM diagnosticó un total de 773 casos de malaria, el HDNR 485, y Sandi Yura 859. Para el mismo cuadrienio se detectó un índice parasitario anual de 40,4 con los datos del HDNR; 35,8 con los de Sandi Yura, y 6,2 con los del SNEM. Plasmodium vivax fue el parásito hallado con mayor frecuencia en el territorio (92% de todos los casos). De las personas infectadas, 28% tenían menos de 10 años de edad. No se hallaron diferencias patentes entre los sexos, ni tampoco variaciones estacionales del número de casos. Es preciso hacer más investigaciones para confirmar estos resultados y para entender más a fondo la transmisión de la malaria en la zona. El estudio subraya la necesidad de fortalecer la coordinación entre las organizaciones que participan en la lucha antimalárica en el territorio, a fin de mejorar los conocimientos sobre la epidemiología de la malaria y de diseñar y poner en marcha estrategias de control adecuadas.

Central burst is a common defect in drawing processes. Although other variables are usually involved, it is widely known that central burst appearance is restricted to large die semiangles and small reductions. Several studies have been developed in order to define the ranges of these variables where this defect is expected to occur. In this study, three different cases have been analysed taken into account the results of previous studies. The combination of reductions and die semiangles provides three different situations to be studied. Because the propagation of cracks is a secondary problem in metal forming processes, the main objective in this work is to avoid their occurrence by means of the observation of variables such as the hydrostatic stress and the strain rate.

Background Musculoskeletal disorders (MSDs) that result from poor ergonomic design are one of the occupational disorders of greatest concern in the industrial sector. A key advantage in the primary design phase is to focus on a method of assessment that detects and evaluates the potential risks experienced by the operative when faced with these types of physical injuries. The method of assessment will improve the process design identifying potential ergonomic improvements from various design alternatives or activities undertaken as part of the cycle of continuous improvement throughout the differing phases of the product life cycle. Methodology/Principal Findings This paper presents a novel postural assessment method (NERPA) fit for product-process design, which was developed with the help of a digital human model together with a 3D CAD tool, which is widely used in the aeronautic and automotive industries. The power of 3D visualization and the possibility of studying the actual assembly sequence in a virtual environment can allow the functional performance of the parts to be addressed. Such tools can also provide us with an ergonomic workstation design, together with a competitive advantage in the assembly process. Conclusions The method developed was used in the design of six production lines, studying 240 manual assembly operations and improving 21 of them. This study demonstrated the proposed method’s usefulness and found statistically significant differences in the evaluations of the proposed method and the widely used Rapid Upper Limb Assessment (RULA) method.

Higher-Order Thought (HOT) theories of consciousness maintain that the kind of awareness necessary for phenomenal consciousness depends on the cognitive accessibility that underlies reporting.

One of the main problems for the scientific study of consciousness is methodological. At least prima facie, the kind of knowledge we have of our own experiences is direct and not mediated by an inference process. This kind of knowledge contrasts with the kind of knowledge we have of others’ experiences, which relies on the observation of their behavior and their reports.

This work presents an analysis of the plate drawing processes carried out in converging dies. The analysis has been made by the upper bound method (UBM), modeling the plastic deformation zone by triangular rigid zones (TRZ), and considering that the processes occur under plane strain and partial friction conditions. The goal is to evaluate how the work-hardening suffered by materials when they are cold-worked affects the energy required to carry out a certain process. In order to achieve this objective, the paper proposes a simplified model for calculating the shear yield stress, k, along the contact surface between die and material when theoretical work-hardening materials are used. The results obtained with this simplified procedure do not differ significantly from those obtained with the complete model, even in the more drastic conditions tried. This result confirms that the simplified model can successfully substitute for the complete model with less calculation.

The present work includes the design, development and establishment of an analysis and evaluation methodology, which allows knowing how a particular document carries out its contents, according to the requirements. The first stage of this work involves the identification of documentary typologies that consider the main part of metrological activities and the different analysis levels are established, either individually, or in conjunction with other documents involved in the process of analysis. Also, evaluation parameters are identified, including numerical values. The methodology developed provides the user with an analysis tool that permits having detailed and complete information about the contents that will be used as reference texts. This way, it will be possible to identify the strengths and weaknesses of each document and it will be possible to optimize their use depending on the activity in which it is working.

Nowadays, some of the key aspects to consider during a manufacturing process are the ones related to its energy study. Choosing the most appropriate process allows to optimize not only technological and economic, but also it influence in sustainability and suitability of the process. In the current work a comparative technological-economic analysis between forming processes and machining processes is developed. We can find that drawing (forming process) has more advantages in most cases.

The scope of this work is to study a forging process at room temperature and at macroscopic level. The mechanism of deformation is influenced by the friction and the reduction ratio, but the influence of the geometry of the billet (aspect ratio) needs also to be taken into account. The objective will be to compare the results obtained during a simulation with the code based on Finite Element Method (DEFORM 2D/3D), with those obtained by analytical methods in order to validate the numerical model. Taking into account that deformation is not uniform and the free surface suffers a phenomenon known as barrel-shaped, that is not covered by analytical methods, the data obtained will compared with those obtained with the FEM code ABAQUS. The aim of this comparison between analytical and numerical methods using two commercial codes instead one, is a proposed way to validate a Finite Element simulation when experimental data are not available or do not exist yet.

The numerical simulation of Localised-Incremental Forging (LIF) is a challenging task. The analysis of LIF operations is often difficult, especially when several strokes are necessary to obtain the final shape of the part. The use of FE models is mandatory because incremental operations throughout a workpiece are difficult to analyse with conventional analytical methods. It is known that, in general, implicit FE models give more robust results than explicit FE models; however, with the former methodology there are several problems that must be faced. With the main goal to extend the analysis capability of LIF operations, some explicit FE models are developed in this paper and results are compared to those obtained by implicit methodology. It can be concluded that taking into account these guidelines, the developed models could be further used in the analysis of multi-strokes LIF operations, where more complicated trajectories will be required.

In 2008, the World Health Organization issued a callback to the principles of primary health care, which renewed interests in social participation in health. In Guatemala, social participation has been the main policy for the decentralization process since the late 1990s and the social development council scheme has been the main means for participation for the country's population since 2002.The aim of this study was to explore the process of social participation at a municipal-level health commission in the municipality of Palencia, Guatemala.Analysis of legal and policy documents and in-depth interviews with institutional and community-level stakeholders of the commission.The lack of clear guidelines and regulations means that the stakeholders own motivations, agendas and power resources play an important part in defining the roles of the participants. Institutional stakeholders have the human and financial power to make policies. The community-level stakeholders are token participants with little power resources. Their main role is to identify the needs of their communities and seek help from the authorities. Satisfaction and the perceived benefits that the stakeholders obtain from the process play an important part in maintaining the commission's dynamic, which is unlikely to change unless the stakeholders perceive that the benefit they obtain does not outweigh the effort their role entails.Without more uniformed mechanisms and incentives for municipalities to work towards the national goal of equitable involvement in the development process, the achievements will be fragmented and will depend on the individual stakeholder's good will.

This work analyses the effect of eight constitutive models on the saw-toothed chip formation in Ti6Al4V orthogonal cutting, by means of the finite element (FE) simulation and experimental contrast, in dry and with conventional emulsion coolant, mixed with water at 7%. The models are focused in Johnson-Cook equations with four different sets of constant parameters, El-Magd-Treppmann modified and three Zerilli-Armstrong models based on the behavior of different crystal structures (body-centered-cubic – BCC, hexagonal-close-packed – HCP and modified HPC model). The flow stress model of Ti6Al4V at high strain rates and temperatures has been analysed using a 2-D FE model through constitutive equations and three friction coefficients (0.4, 0.6 and 0.8). A critical comparison of outstanding process outputs as cutting force, temperature – on rake face and measurable parameters for segmented chip (the peak tooth height, the valley tooth height and the tooth width, chip compression ratio, and chip deformation) is carried out. The application of different constitutive models has proved a strong influence on the results. Zerilli-Armstrong models, for BCC and HCP structures, have achieved the best fitting in machining with and without coolant respectively, for a friction coefficient of 0.8, getting for cutting force, temperatures, peak tooth height and chip deformation, deviation lower than 2%. The chip compression ratio has reached 4.7% and 7% for BCC and HCP respectively. Only the valley tooth height and the tooth width show some limitations.

This paper deals with the simulation of UNS A92024 aluminium alloy cutting processes. In particular, 2D and 3D Finite Element Method (FEM) simulations were carried out in order to estimate cutting forces and chip morphology during turning operations. The material is modelled with two different set of parameters for the Johnson—Cook’s (J‐C) constitutive equation and a failure Cockroft and Latham’s model exploited considers damage. The comparison between the predicted chip morphology and principal cutting forces at varying of J‐C parameters and cutting regimes with those experimentally found are presented and discussed. The paper shows the importance of damage criterion in the cutting forces, during the simulation, especially in 3D.

This paper presents a global solution for solving industrial processes of plastic deformation through a sustainable manufacturing system (SMS). The requirements of multi-stage plastic deformation processes which are characterized by their need to be solved in several stages, tend to increase their process time and associated costs. The proposed SMS is capable of obtaining a global solution for these processes. The proposed solution framework is a System of Systems (SoS) made up of the following four distributed, complex and component systems or sub-systems: scientific, technological, economical and environmental. The three case studies considered in this paper not only demonstrate the potential of the SoS approach in representing the proposed SMS in order to find the global solution in terms of its total process time, total cost, and total energy consumed during the process but also the significant improvements that could be achieved by this method.

Manufacturing processes are an important element in industrial engineering education. In distance education, the learning of engineering subjects has a special difficulty, which can be reduced by means of the use of new technologies, and the practice of mixed models of learning. One of these processes is the deep drawing due to its relevance in the industry. This paper presents a deep drawing tool for e-learning. The tool has been realized for its use in the Master degree because it requires advanced knowledge in manufacturing processes. The instrument has been developed with the objective of the students who can: a) Select input data for get the formability of material to deep drawing; b) Select the process that provides the best solution from a technological perspective; c) Optimize the process for saving the material; d) Know the influence of the punch in the results; e) Consideration of the process cost. The structure of the system has three subsystems: a) Solve, module for data processing and the generation of results; b) Materials, module for management data of the system; and c) Interface, module for user interaction. The tool has been implemented in the software tool programming, developed in Java. This language has been selected because it provides a methodology of object-oriented programming and its execution is possible in multiple operating systems. The paper describes each step of the tool, from the input data to final analysis and they are shown through the results given by the tool.

This paper present a model for the integration for the standardization integration inside the technical teaching in university context, taking into account the established requirements by the European Higher Education Area (EHEA). This methodology is based on the development of a new typology of document named as “standard supplement”. The proposed methodology serves to identify the set of documents witch are necessaries in a specific subject, the knowledge, abilities and attitudes to identify with the academic competences, previously defined, and a guide for the development of the contents of each “standard supplement”. The proposal structure of “standard supplement” is appropriate to different level of complexity and could be used as a link between enterprises and engineering education.

Titanium alloys are materials considered as extremely difficult to cut and titanium alloy Ti6Al4V is a reference in machining of titanium. The segmented (saw toothed) chip morphology has attracted great interest in researchers because the understanding of the saw‐toothed chip morphology helps to understand the chip formation mechanisms. In this study, the effect of different constitutive models on the saw‐toothed chip morphology is examined in machining Ti6Al4V. The paper presents the influence of eight material constitutive modelling in the simulation of segmented chip formation. A critical comparison of outstanding process outputs as cutting force, temperature and measurable parameters for segmented chips is carried out to compare and discuss the performance of the eight different material models to each other and with experimental data.

Virtual reality techniques use at industrial processes provides a real approach to product life cycle. For components manual assembly, the use of virtual surroundings facilitates a simultaneous engineering in which variables such as human factors and productivity take a real act. On the other hand, in the actual phase of industrial competition it is required a rapid adjustment to client needs and to market situation. In this work it is analyzed the assembly of the front components of a vehicle using virtual reality tools and following up a product‐process design methodology which includes every life service stage. This study is based on workstations design, taking into account productive and human factors from the ergonomic point of view implementing a postural study of every assembly operation, leaving the rest of stages for a later study. Design is optimized applying this methodology together with the use of virtual reality tools. It is also achieved a 15% reduction on time assembly and of 90% reduction in muscle—skeletal diseases at every assembly operation.

In the study of compression processes, analytical methods use to be applied under plane strain conditions due to limitations of their own formulation. However, axisymmetrical workpieces are more commonly used in industrial processes, so the use of numerical methods is often neccesary. In this sense, the Finite Element Method (FEM) is a powerful numerical tool that can simulate more realistic conditions of these processes. In the study of compression processes between parallel flat dies (such as forging or indentation) several parameters are usually involved. The friction on the flat die‐workpiece interface is is one of the most important parameters to be considered. Additionally, other factors mainly related to the geometrical dimensions of the problem are also relevant. Mainly, attending to the geometry of the problem different cases can be defined. Thus, the indentation and the forging of a cylindrical billet can be similarly studied assuming different dimensions of the dies and the workpiece, in each c...

Two finite element simulation techniques are applied for the analysis of a basic operation in LIF processes. Implicit and explicit numerical methodologies are used by Abaqus/standard and Abaqus/explicit solvers, respectively. The most suitable mesh and geometry of the punch have been chosen among different ones according to the computation time, accuracy of results and forming capability. Once the mesh and the geometry of the punch are chosen, a single operation is simulated by means of both implicit and explicit FE models. Experimental tests were also conducted. Forces and geometrical profiles were compared among those obtained by experiments and simulations and the results show good correspondence. The explicit FE model looks robust enough to use the same modelling parameters in further studies, where explicit methodology is expected to be mandatory due to multiple–strokes operations.

We are moving away from the year 2000, and the goal of "health for all" remains distant. Economic globalization, which many consider to be one of the most serious threats to health, moves ahead, along with globalization of international health policies. A small number of powerful actors are in charge of setting the agenda, and they relegate to an inferior position the World Health Organization, which has moved away from the goal of "health for all." All of this has helped to promote a neoliberal mentality in the field of health. The People's Health Movement was created with the objective of reestablishing the right to comprehensive health and to development with equity as principal priorities of health policies at the local, national, and international levels. The People's Health Movement uses as a strategy the People's Charter for Health, which was approved at the first People's Health Assembly, which was held in Bangladesh in 2000. The Charter expresses collective concerns and the belief in a better and healthier world as a meeting point in order to promote a world health movement and a call for radical action. In July 2005 the People's Health Movement will hold the People's Health Assembly 2, in the city of Cuenca, Ecuador. The slogan of that meeting will be "The voices of the earth are calling!--let's build a healthy world." Among the topics that will be examined at the meeting are: health as a fundamental human right; militarization and occupation; environmental degradation; emerging and reemerging pandemics; equity, poverty, and health; the importance of cultural diversity; social and political violence; health in the hands of the people; health at work; traditional medicine and bioenergetic medicine; gender; and health sector reform. The objective of the People's Health Movement is to help to reach the Millennium Development Goals and to smooth the path toward attaining health for all, in Latin America and the Caribbean as well as in the rest of the world.

To assess the nutritional status of Naporuna children under five years of age from the Amazon region of Ecuador, and to identify risk factors for developing malnutrition in this population group.A survey-based cross-sectional study was carried out in Orellana, a province in northeastern Ecuador, between June 2001 and February 2002. Household interviews were conducted in 30 communities chosen at random, and a questionnaire was used to record the following: the social and demographic characteristics and parity of mothers having children under five years of age, and the children's demographic and anthropometric characteristics, history of breastfeeding, and medical conditions suffered over the two-week period just prior to the survey. Each child was also subjected to a physical examination. Anemia was diagnosed clinically by conjunctival exam. The statistical association among variables was determined by means of the chi-square test, with use of Yates' correction and Fisher's exact test (two-tailed) when there were 5 observations or less. Risk factors for chronic malnutrition and underweight were determined by means of logistic regression.Overall, 189 mothers of 347 children under five were interviewed. Of these 347 children, 307 (88.5%) participated in the study. Chronic malnutrition was found in 22.8% of the children; 26.4% were underweight, and 9.8% had acute malnutrition. Moreover, 7.5% had severe chronic malnutrition; 4.9% were severely underweight, and 1.6% had severe acute malnutrition. A total of 5 children (1.6%) showed signs of both chronic and acute malnutrition. The largest prevalence of chronic malnutrition was found in the 12-23 month age group. Risk factors for chronic malnutrition that were statistically significant included living in an area without access to a road, the total number of children in the family (or =7), and the presence of an acute respiratory infection or abdominal distension on the day the physical examination was performed. Abdominal distension and pale conjunctiva on physical examination were predictive for underweight.Among the Naporuna children under 5 years of age included in this study, the prevalences of acute malnutrition and underweight appeared to be higher than had been previously detected among other populations in the Amazon region. More studies on the prevalence of parasitic infections and anemia and on the feeding practices and dietary habits of indigenous communities are needed in order to better understand their nutritional intake. A program for monitoring the diet of indigenous peoples is necessary and should be established.

To determine the prevalence of anemia in rural school-age children in the Amazon region of Ecuador.We carried out a cross-sectional study during May to October 2000 in two cantons of the province of Orellana, in northeastern Ecuador, involving 626 children from 17 schools. Demographic and anthropometric data (weight and height) were collected, values for hemoglobin and for zinc erythrocyte protoporphyrin were determined, and feces samples were analyzed to check for infestation by parasites.The general prevalence of anemia was 16.6% among the schoolchildren; of the affected children, 75.5% of them had iron-deficiency anemia. The prevalence of moderate chronic undernutrition was 28.8% and that of serious chronic undernutrition was 9.3%. There was also a prevalence of moderate acute undernutrition of 8.4% and of severe acute undernutrition of 3.4%. Parasitic infections were very frequent (82.0%). The most common parasites were Entamoeba coli (30.3%) and Ascaris lumbricoides (25.0%). There were no relationships between the prevalence of either anemia or of iron-deficiency anemia and any of the indicators of nutrition or of parasitic infection.Anemia is not a serious public health problem in the population studied. Nevertheless, the high prevalence of chronic undernutrition among the children points to the need to improve their diets. The lack of association between the prevalence of undernutrition and anemia could be due to low iron bioavailability or absorption rather than insufficient intake. Studies are needed to evaluate the customary diet of this population.