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espanolEl objetivo del estudio de caso es desarrollar una taxonomia de los factores humanos que influyen en los errores humanos y fallas que provocan defectos en la calidad del producto en la industria de manufactura de dispositivos medicos de la ciudad de Tijuana, Baja California, Mexico. La metodologia es cualitativa-cuantitativa y se fundamenta en la Teoria del Consenso Cultural de la Antropologia Cognitiva. La investigacion tiene cuatro etapas secuenciales con un enfoque de metodos mixtos para la recopilacion y analisis de datos. La etapa I consiste en un estudio contextual de la industria de manufactura a 67 empresas. En la etapa II participaron cinco empresas y se uso el enfoque cualitativo con el instrumento de investigacion llamado listados libres. En la etapa III, la tecnica de sorteo por montones sucesivos se aplico en la recopilacion de datos para la clasificacion de los elementos del Dominio Cultural. En ambas etapas participaron entrevistados de altos y medianos mandos de las empresas. En la etapa IV se realizo una evaluacion de los conocimientos de los operadores multifuncionales; el instrumento de investigacion fue una encuesta con escalas de calificacion disenada a partir de los elementos del dominio cultural descritos en la etapa III. La validez interna de la encuesta y la confiabilidad de los participantes fueron estimadas con el coeficiente Alfa de Cronbach. El resultado principal fue una taxonomia integrada por cinco categorias: factores tecnicos, factores organizacionales internos, factores organizacionales indirectos, factores personales, factores humanos directos. Aun cuando la taxonomia no ha sido validada, se visualizan aportaciones de naturaleza practica. EnglishThe objective of the case study is to develop a taxonomy of the human factors that influence human errors and failures that cause defects in product quality in the medical device manufacturing industry in the city of Tijuana, Baja California, Mexico. The methodology is qualitative-quantitative and is based on the Cultural Consensus Theory of Cognitive Anthropology. The research has four sequential stages with a mixed method approach to data collection and analysis. Stage I consists of a manufacturing industry contextual survey of 67 companies. In stage II, five companies participated and the qualitative approach was used with the research instrument called free listings. In stage III, the technique of drawing lots by successive piles was applied in the data collection for the classification of the elements of the Cultural Domain. Interviewees from top and middle management of the companies participated in both stages. In stage IV, an assessment of the knowledge of the multifunctional operators was carried out; the research instrument was a survey with rating scales designed based on the elements of the cultural domain described in stage III. The internal validity of the survey and the reliability of the participants were estimated with Cronbach's Alpha coefficient. The main result was a taxonomy composed of five categories: technical factors, internal organizational factors, indirect organizational factors, personal factors and direct human factors. Even though the taxonomy has not yet been validated, it has made contributions of a practical nature.

Este trabajo contiene el sistema hombre-máquina del área de maquinado, basado en la configuración serie-paralelo y en las relaciones componente-subsistema. Se utilizó el análisis de causas y un sistema de clasificación mediante el Análisis de Conglomerados, para analizar las piezas no conformes ocurridas en 3 talleres de maquinado del sector metalmecánico y diseñar el modelo del sistema hombre-máquina. El propósito del modelo del sistema hombre-máquina es proveer las condiciones adecuadas para aplicar algunos modelos estadísticos para evaluar la confiabilidad, con en el enfoque de los sistemas serie-paralelo y bajo los supuestos de una tasa de falla constante y aditiva de las distribuciones Exponencial y Weibull respectivamente. Como una entrada del primer modelo estadístico se utilizaron los tiempos para las fallas de las piezas no conformes y pruebas de bondad de ajuste, para evaluar la confiabilidad de las relaciones componente-subsistema. Para el segundo modelo estadístico, se utilizaron las confiabilidades de las relaciones componente-subsistema, para evaluar la confiabilidad de los subsistemas, con la configuración de sistemas en serie. Las entradas del tercer modelo estadístico, se utilizaron las confiabilidades de los subsistemas, para evaluar la confiabilidad del sistema hombre-máquina, con la configuración de un sistema en paralelo. El sistema hombre-máquina y los modelos estadísticos fueron implementados y validados en una compañía del sector metalmecánico con una tasa de producción de bajo volumen y alta mezcla, cuyas operaciones son realizadas por máquinas convencionales y de Control Numérico (CNC). Con el Sistema hombre-máquina fue posible conocer la estructura formal de las áreas de maquinado desde las piezas no conformes del área de scrap e identificar las subcausas de falla que afectan al sistema (componentes). Los componentes identificados fueron: mantenimiento/set up, condiciones institucionales/actitud, perfil de ingreso, información/comunicación, calibración y proveedor. También fueron identificados los lugares más comunes donde ocurrieron las fallas (subsistemas). Los subsistemas identificados fueron: máquina, herramienta, proceso/operación, medición/instrumentación, programación/diseño y material. A través de los modelos estadísticos fue posible obtener los índices de confiabilidad para cada relación componente-subsistema, para cada subsistema, así como para el sistema hombre-máquina, identificando así áreas para la mejora. La compañía donde se implementó y validó la metodología, presentaba un alto índice de scrap en el área de maquinado y fue posible identificar que el subsistema proceso/operación y los componentes mantenimiento/set up y condiciones institucionales/actitud tuvieron la confiabilidad más baja y fueron consideradas como áreas de oportunidad para la mejora. Durante 7 horas la confiabilidad hombre-máquina es de 0,1409 (la probabilidad de encontrar un producto sin fallos para el que debe ser desechado es del 14.09%). En el taller de maquinado, los problemas que causaron estos bajos niveles de confiabilidad se atribuyen al insuficiente programa de mantenimiento preventivo y predictivo. Las acciones para la mejora están consideradas en otra investigación. Este tipo de investigación estudia un problema poco estudiado, como es la confiabilidad del sistema hombre-máquina en áreas de maquinado e investiga desde una perspectiva innovadora, además de preparar el campo para nuevos estudios en el sector metalmecánico.

El objetivo de este trabajo fue validar la confiabilidad y validez estadística de la NOM-035-STPS-2018, en específico del dominio Relaciones en el trabajo. Metodológicamente, se aplicó la Guía de Referencia III para recopilar datos mediante un muestreo no probabilístico en tres compañías automotrices de Ciudad Juárez, México. En total, 250 supervisores respondieron el instrumento. En primer lugar, se verificó la confiabilidad mediante el alfa de Cronbach y alfa ordinal. Posteriormente se realizó la prueba de Kaiser-Meyer-Olkin (KMO) y Bartlett. Entre los resultados, el dominio Relaciones en el trabajo obtuvo un alfa de Cronbach de 0.913, mientras que las dimensiones “Relaciones sociales en el trabajo” y “Deficiente relación con los colaboradores que supervisa” obtuvieron valores de este indicador de 0.879 y 0.975, respectivamente. Por otro lado, el alfa ordinal obtuvo valores superiores a 0.90 en las dos dimensiones. El KMO obtenido fue de 0.838 y la prueba de Bartlett resultó ser significativa (p = 0.000). En consecuencia, el análisis factorial exploratorio extrajo los dos factores propuestos por la norma. Dichos factores contribuyen a 79.11 % de la varianza acumulada. El análisis factorial confirmatorio mostró un buen ajuste del modelo. En conclusión, el instrumento y las dimensiones propuestas pueden ser utilizados como herramienta de evaluación para medir el factor psicosocial Relaciones en el trabajo (dominio de la NOM-035), ya que muestran valores aceptables en términos de confiabilidad estadística.

La medición es un aspecto clave para evaluar el resultado de cualquier proceso. Las líneas de ensamble deben medirse considerando la confiabilidad tanto del producto como del proceso de producción. El propósito de este estudio fue desarrollar una metodología que permitiera conocer el estado de una línea de ensamble y que integrara un modelo de medición para obtener un índice de confiabilidad para una línea de este tipo de la industria automotriz. Los dos productos resultantes de este estudio fueron la metodología con su estructura en etapas y el modelo matemático. La metodología está compuesta de cinco etapas y el modelo de cuatro elementos. La confiabilidad pudo ser calculada para una línea de ensamble de la industria automotriz haciendo uso de la media de la distribución de mejor ajuste. Lo anterior permitió detectar el índice que más afectó a la confiabilidad general. El índice que más afectó al valor de confiabilidad general fue el de disponibilidad con 75.55 %, seguido del índice de eficiencia con 87.25 %, continuando con el índice de calidad con 90.15 % y, por último, con el menor efecto, está el índice de capacidad de entrega con 97.75 %.

Companies are in constant search of greater productivity and better use of resources; however, they have neglected the human being. In this regard, it is important to analyze the presence of the psychosocial factors to which workers are exposed at all levels. These factors exert both a positive and a negative influence and indeed turn into a risk when they are not in balance with worker capabilities. This literature review aims to provide a comprehensive understanding of the psychosocial factors present in the manufacturing industries. The methodology consisted of conducting a search in two databases in addition to government pages. A combination of keywords was used for the search, and each publication was classified according to the factors analyzed, the type of evaluation, and the area of application. Out of all 2,468 publications found, eight were selected. Finally, work-related psychosocial factors were found to be the most analyzed.

Usability is the characteristic of a software product of being effective and efficient and producing satisfaction for users and traditionally is assessed through questionnaires but most of them are only available in English. A software usability assessment questionnaire (SUAQ) is proposed in two languages: Spanish and English. The methodology comprises four stages: 1) questionnaire development, 2) administration, 3) statistical validation, and 4) sample size determination. Twenty items were evaluated in terms of clarity, consistency, and relevancy. Then, the SUAQ was administered to 95 respondents. Overall, reliability values were acceptable in Spanish and English version, respectively. The factor analysis was feasible since the KMO index, and the Bartlett sphericity test was statistically significant. Both versions of SUAQ were tested to determine their validity. The findings show that the proposed methodology is an effective usability assessment instrument and thus an effective software improvement tool from a bilingual approach.

This article presents the design of a computerized system for the traceability and reuse of pieces, where it impacts on the reduction of manufacturing costs, contributing to the decrease in the consumption of natural resources. The components to be reused are recovered from a complete used equipment, starting from a list of all its parts. The system facilitates the traceability of the components that need to be recovered, reducing the time of location and supplying parts to the production areas. In addition, it avoids the saturation in the warehouse area of parts that are not required. This system will have data in real time and concise on the inputs and outputs of raw material, speeding up the reception of equipment, making the capture of input inventory. As a result, it will lead to better production planning, increasing the recovery rates of the required components, making the most of the storage area, decreasing equipment unloading times. In addition, it will allow a better costing of inputs and outputs of the company. On the other hand, the software development cost was minimal, and could have a considerable impact on the profits of the industry, ecology and the economy where it is implemented.

Background Usability is an essential characteristic of software development, which needs to be evaluated mainly through questionnaires. However, the questionnaires available in Spanish are limited and not available for most software's developers and users. Objectives This work aimed to design and validate a new questionnaire to evaluate software usability, considering the characteristics of efficiency, effectiveness, and satisfaction as defined by the International Standards Organization. Methods The Software Usability Assessment Questionnaire or SUAQ in Spanish language was designed and validated using Kendall's coefficient, Cronbach's Alpha, Factorial Analysis and Scree test. Results The questionnaire's validation was carried out by five experts through an evaluation of the clarity, coherence, and relevance of the proposed items. Once the questionnaire was administered to 95 participants, an overall reliability value of Cronbach's alpha of 0.839 was obtained. The factorial analysis is viable since a value of 0.757 was found in the Kaiser-Meyer-Olkin (KMO) test, and a significant value was obtained in Bartlett's sphericity test. Conclusions The proposed questionnaire proved to be valid and reliable, and therefore, suitable to evaluate software usability in the Spanish language.

The information provided by brainwaves allows the identification of many things such as: mental diseases, fatigue, stress, attention span and level of engagement, for example in the area of logistics, transportation accidents occurred due to driver’s fatigue. These accidents might be prevented by monitoring the cognitive states with the help of Electroencephalograms (EEG), with a substantial impact in the supply chain processes. Nowadays, manual assembly operations are still used in the industry, in spite of the current technological advances. The experiment carried in this work comprised the manual assembly of a Legos car containing 122 small pieces. The production line in a laboratory setting was divided into three work stations. The experiment length was three hours for each person. Also, in each hour the standard time was changed in order to increase the mental work load of the workers. The first hour was performed at 100%, the second at 80% and the third at 70% of the standard time. The Emotiv Epoc wireless device and the Emotiv Pro software were used to record brain activity (EEG). This work focused in the existence of differences regarding the behavior of brainwaves within the three people who performed the experiment and, also in the presence of differences during the three standard times. The results of the study showed that, there is a statistically significant difference when working with three different standard times and there are also differences in the brainwaves behavior of the people who performed the experiment.

We propose a methodology for determination of Allowance Time (AT), based on heart rate and work sampling of a production line composed of thirteen stations operated by four workers. The current production line presents a high rate of personnel turnover and absenteeism and with an AT value established by the company of 6.3%. The AT determination is of critical importance, given that through this the workers need to maintain their work rhythm at 100% during the entire workday without fatigue. The resulting allowance after the study was 15% instead of 6.3%, increasing the standard time and causing a decrease in personnel turnover and absenteeism and consequently increasing the production capacity and the reduction of costs.

This chapter discusses the definitions of environmental design, design for remanufacturing (DfR), as well as a case study to demonstrate the convergent point between these topics. Many products that are currently remanufactured were not designed with this objective, generating a complicated process that requires that the manufacturing engineers develop in a corrective way, modifications in the original design of the products related to its components and the process. The case study analyzes a product that was not originally designed as remanufacturable. The decision was made to develop a reconstruction process that fulfilled the characteristics of remanufacturing. Finally, in applying the DfR, it was possible to expedite the remanufacturing so that material planners do not fear to run out of good parts and have to order the purchase of new product, decrease the use of assembly details that are purchased at a high price, and thus save on the cost of remanufacturing. Analyzing this case and applying DfR implied a savings of 37% compared to the initial process that did not apply this tool.

This article discusses the history of the Social Responsibility (SR) in Mexico are presented. When words social responsibility are used, usually refer to donations and philanthropy. Some engineers think the environment is, in their ecological responsibility. It is believed that the company in addition to fulfilling its legal obligations, is required to “return to society” a certain annual amount, thinking thus becomes the RS in a “social quota”. Late last century, the third sector or nonprofit sector in Mexico had a major expansion to increase the generation of new laws to strengthen civil society, supporting with funding to private welfare organizations to acquire legally, and either a civil partnership or private assistance institution. For the realization of this work was carried out a literature review to find a relationship between the theoretical and the empirical study of the subject.

With the vision to maintain leadership, enterprises are working to implement a green business strategy. The increase in the solid waste generation has promoted interest in the remanufacturing production system, which is considered the best end-of-life (EoL) alternative. In Mexico, remanufacturing takes place mostly in small workshops, including products as electronics, auto parts, heavy-duty engines, gas turbines, and others. However, on the Northern Border are located industrialized remanufacturer companies with global presence, these are characterized by monitoring the indicators of sustainability. This article presents an exploratory study on the current remanufacturing scenario and its main characteristics within the Mexican remanufacturing sector. This research is an analysis of three transnational remanufacturing enterprises located in this region; it selected the metalworking industrial sector. The objective of this study is to identify the elements are integrating its production system; make a comparative analysis of them and contrast them to identify similarities, differences, advantages, and disadvantages. The research is an attempt to review in a critical way remanufacturing practices and develop a theoretical framework.

The aim of this study was to develop a taxonomy of human factors that influence human errors and faults that cause injury accidents in hands in the automotive manufacturing industry harnesses. The methodology cultural consensus theory of Cognitive Anthropology with a mixed-method approach to collecting and analyzing data was used. Collection instrument known as free listings to identify about the point of view of members of the security group, successive card sorting was applied in data collection for the classification of the elements of the cultural domain. The statistical models; multidimensional scaling and cluster analysis were applied to obtain mutually exclusive and high-level categories, internal validity and reliability of survey participants were estimated with Cronbach’s alpha coefficient. The main result was a taxonomy composed of five categories: unsafe acts, unsafe conditions, personal factors, supervision and organizational factors. Future studies are required to validate the taxonomy.

This document presents a study of human factors that influence human errors from the perspective of cognitive ergonomics. The purpose of the research is to determine the root of human errors from the perspective of the human factors that affect the quality of the product. The study of took place in the context of the Maquiladora Industry. The scientific methodology used is located in Cognitive anthropology, through the application of the theory of the Cultural consensus. The methodological approach of the study corresponds to the mixed methods. The design of the study was cross-sectional, descriptive and analytical. The population studied was that of multifunctional operators, existing in the company’s two modalities: those in manufacturing support and those in quality inspection support. With this research, it is possible to move closer to a classification of the causes root of human errors that affect the product quality in the industry maquiladora in Tijuana, Mexico. With this knowledge it is possible to propose preventive actions in Maquiladora improvement projects.

Due to the scarcity of natural resources, the high competitiveness between companies and the need to create new business opportunities, some manufacturers are becoming interested in activities that involve more complexity than conventional manufacturing of its products. This is the case of companies being the original manufacturers of a product, engaged in reverse logistics to recover it at the end of its useful life and apply remanufacturing. The main objective of this research is to identify how human factors influence the activities of planning and production control, specifically in the remanufacturing process. However, it is interesting to note that it is not possible to establish a fair comparison between the conventional manufacturing process and remanufacturing in this regard. Remanufacturing is a process with greater uncertainty, so that establishing relationships with influential human factors allows: first, to make a more realistic approach to the situation in the company; second, determine the manner in which the staff makes decisions about the process and; third, develop a strategy allowing the company to improve its key performance indicators. Remanufacturing, is a relatively new process, the papers found with this approach are scarce. So conducting exploratory, descriptive and explanatory research was considered. To start this research, a study was conducted including employees of seven companies in the auto parts remanufacturing industry. In the first place, semi-structured interviews were applied; thereby the basic information to design the survey was obtained, which prior to its implementation was validated. After collecting the data, a confirmatory factor analysis was developed. Subsequently, we proceeded with the design and implementation of a SEM (Structural Equations Modelling). This allowed proposing a theoretical model to interpret the information provided by employees in the implementation phase of interviews and surveys. The model is convincing in demonstrating that the activities of planning and production control in remanufacturing are strongly affected by the human factor and has a significant impact on its key performance indicators.

In this chapter an Ergonomic Compatibility Evaluation Model for the selection of Advanced Manufacturing Technology (AMT) into a Lean Six Sigma Manufacturing Framework is proposed. The approach was applied on the selection of CNC plastic molding machines for an AMT training center. The purpose of this model is to constitute a decision aid for decision makers to perform evaluations of AMT in a more complete manner, while considering human factors and ergonomic aspects. These aspects are found to be scarce in actual AMT evaluation and selection models. Model was created using a multi-attribute axiomatic design perspective supporting the selection of AMT. In this chapter a theoretical Lean Six Sigma Framework was proposed for its application. A numerical example is presented by the application of the model with the participation of three experts. A procedure including phases with several steps was deployed using the Define, Measure, Analyze, Improve and Control (DMAIC) stages for AMT evaluation. The alternative which best meet established Design Ranges in terms of Ergonomic Compatibility was selected among three alternatives, according to the Ergonomic Incompatibility Content in a fuzzy environment.

Assessment of workplace risk is generally accepted as the basis of any effort to manage it. Researchers have emphasized on the need to incorporate human factors in risk assessment, due to the increasing relevant role of humans in the modern work environment. The aim of this chapter is to offer a theorical approach for human factors identification and classification system in accidents’ causality in manufacturing environment. This chapter emphasizes in the study of human error as a relevant aspect in the human factors approach. It presents an introduction to human error taxonomies. Also, a new taxonomy is proposed and developed in a case study. The Swiss Cheese defense model developed by Reason is treated in detail because it has built the theoretical fundaments for the proposed taxonomy applied in the manufacturing industry for automotive harnesses. Finally, an application of the proposed taxonomy is shown, using accident report found in the database of an international automotive wire harness manufacturing corporation.

The causes of occupational accidents from the perspective of human factors have been a subject which has received little attention into the field of scientific research. The aim of this research was to identify and classify the human factors that influence human errors and failures that cause accidents and injuries specifically on hands. Available studies related to the topic have been developed mainly for aerospace applications and are found insufficient to explain accidents causalities in the manufacturing industry. This research was developed in the assembly industry of automotive harnesses and was conducted following a mixed Cognitive Anthropological approach. This study was developed in two phases. During the first qualitative phase, participants freely listed their knowledge to identify elements of the cultural domain, then and in the second phase they performed the successive pile sort technique for the collection data to classify elements in the cultural domain. Statistical models like Cluster Analysis and Multidimensional Scaling were applied for results' validation purposes. As results, 70 different human factors were identified and in the second phase they were classified into 4 main categories which were: human error, unsafe conditions, individual factors, and organizational factors. Statistical methods validated these results. Language: en