Techniques and Emerging Trends for State of the Art Equipment Maintenance Systems - A Bibliometric Analysis

The increasing interconnection of machines in industrial production on one hand, and the improved capabilities to store, retrieve, and analyze large amounts of data on the other, offer promising perspectives for maintaining production machines. Recently, predictive maintenance has gained increasing attention in the context of equipment maintenance systems. As opposed to other approaches, predictive maintenance relies on machine behavior models, which offer several advantages. In this highly interdisciplinary field, there is a lack of a literature review of relevant research fields and realization techniques. To obtain a comprehensive overview on the state of the art, large data sets of relevant literature need to be considered and, best case, be automatically partitioned into relevant research fields. A proper methodology to obtain such an overview is the bibliometric analysis method. In the presented work, we apply a bibliometric analysis to the field of equipment maintenance systems. To be more precise, we analyzed clusters of identified literature with the goal to obtain deeper insight into the related research fields. Moreover, cluster metrics reveal the importance of a single paper and an investigation of the temporal cluster development indicates the evolution of research topics. In this context, we introduce a new measure to compare results from different time periods in an appropriate way. In turn, among others, this simplifies the analysis of topics, with a vast amount of subtopics. Altogether, the obtained results particularly provide a comprehensive overview of established techniques and emerging trends for equipment maintenance systems

Patent analysis as an input to strategy: case of electric vehicle industry

This research work examines technological developments of an emerging field from the perspective of patented innovations and major industry players. The selected domain of the study is the electric vehicle (EV) industry, which represents an emerging technological field driven by innovations. Patent-to-patent citation information and entities associated with each patent (i.e. patent holder, technology field, country) were utilized for the visualization of the relationship between patents in the form of a network. Bibliographic coupling (BC) is the methodology used to establish these relationships. From the viewpoint of companies, this relationship indicates similarities in the technological development direction and areas of R&D activities, suggesting for possible competition or cooperation. From the perspective of patented technology, the association indicates that the technologies or their applications are closely related. The focus of the study is placed on the possibilities and limitations provided by patent analysis based on BC, so to facilitate further exploration and application of this methodology as a valuable tool for the support of managers' assessment of technological environment in real time and planning of the R&D projects within an emerging field. Managers can use patent maps as an additional source of information and communication support in the strategic decision-making process. Using the bibliographic information of patents, the technological landscape and recent developments in EV sector during the recent six years were analyzed based on the statistical examination and the graph theory provided by social network analysis. Citation networks were divided into clusters, the patent assignee in each cluster were tracked, and citation networks with characteristic technology field for each cluster were analyzed. Overall structural changes of the EV industry were explored by categorizing patent assignees into four main groups, i.e. automotive OEMs, suppliers, infrastructure providers and other players, and exploring the changes in patenting activities between these groups. Analysis of patent network dynamics reveals the changes in the structure of innovation landscape within an emerging field of EVs. Expert opinion of a Finnish automaker was included in the analysis of this study. Limitations of the methodology and suggestions for further research directions are discussed

Output, collaboration and impact of e-learning research: Bibliometric analysis and visualizations at the country and institutional level (Scopus 2003-2016)

Bibliometric indicators of production and impact of e-learning research are analyzed to know the contribution of countries and institutions in the scientific development of this subject and to strengthen its characterization as knowledge domain. We extracted bibliometric indicators from 39,244 documents indexed in Scopus and SCImago  Institutional  Rankings, and generated maps of production and collaboration networks and graphics about the impact of e-learning research in countries and institutions. The results of this combined analysis showed that at country level the United States produce most of the works and generated the greatest international collaboration. At institutional level, the University of Hong Kong is the most productive and National Taiwan University of Science and Technology is the one with the greatest collaboration. In addition, the analysis showed that Taiwan ranks first in productivity and impact, which is why we linked these results to a brief analysis of its national policies. This study presents a new method to analyze both emerging and established knowledge domains

A Bibliometric Study on Innovation and Firm Performance: Building a Research Framework

In response to a rising interest in the connection between innovation and firm performance, this paper examines the body of research on this link and takes a closer look into the influences on innovation, firm performance or both. The basis for this study is a bibliometric analysis of 3,462 scientific publications. We identified 27 innovation domains with an influence on firm performance, showed the rising interest in the topic and found that most types of innovation have a positive impact on firm performance. We provide an overview of which indicators researchers used to measure innovativeness and firm performance and what methods they used to establish the link between the two. Additionally, we stress the importance of sustainable innovation and show that these also positively influence firm performance. In the end, we structure all research fronts into three different groups and based on that, develop a framework that visualizes research on innovation and firm performances

Unreflective use of old data sources produced echo chambers in the water-electricity nexus

This meta-analysis of over 2,400 papers tracks the influence of older publications that have 'echoed' through the decades, cited in countless publications and creating a potentially false confirmation bias. Echo chambers in science describe the amplification and repetition of information within closed networks. Frequently used data sources can cause echo chambers as scientists keep reading similar outputs from different sources, creating false perceptions of certainty and variety of data sources. We show this effect by studying the scientific and grey literature on water use by electricity systems. The power sector is the largest contributor to anthropogenic carbon emissions and the second largest water consumer. We have assessed the scope and references of 2,426 papers and created a citation network to trace original data sources. Most data sources used for the last 30 years originate from a few old US publications, recently also Chinese, that echo through publications. This echo effect, also reflected in recent scientific publications, creates a confirmation bias, also facilitating double counting of the water intensities of electricity generation. This example from sustainability science warns of the risk of echo chambers in other scientific disciplines

Caracterización del e-learning como dominio de conocimiento

El objetivo general de esta investigación es construir el dominio científico del e-learning a través de la aplicación de indicadores bibliométricos para analizar las estructuras bibliométricas de la producción científica que se relaciona de manera directa con la investigación en esta área emergente.Metodología. El análisis bibliométrico se enfoca en la identificación de las características que contribuyen a la determinación de un dominio de conocimiento en el sistema mundial de la ciencia. Estas son, A) el reconocimiento de los canales de comunicación científica utilizados por los investigadores del área temática. Se busca identificar el conjunto de revistas científicas y actas de conferencias que publican trabajos relacionados con el área temática, analizando su cohesión mediante la combinación de los indicadores de citas, co-citas y coupling; B) la comparación de los indicadores bibliométricos de producción a nivel global y regional. Se analiza la evolución de la producción mundial en e-learning, segmentándola por los principales bloques de países e identificando la contribución de cada uno de ellos con respecto a la literatura primaria (article, conference paper y review).

Detection of emerging lines of research in networks of scientific publications

Orientador: Rosangela BalliniTese (doutorado) - Universidade Estadual de Campinas, Instituto de EconomiaResumo: Esta tese busca detectar linhas de pesquisas emergentes utilizando a abordagem computacional baseada em análise de redes sugerida por Shibata et al. (2008). Este método surge como alternativa para uma análise sem a necessidade de intervenção de especialistas do campo estudado. Verificou-se o desempenho do método para uma rede com elevado número de publicações, forte ligação interdisciplinar e conexão com a indústria (bioenergia), e uma rede de publicações do campo das ciências sociais com baixa conexão com o setor produtivo (empreendedorismo). Na análise de publicações científicas em bioenergia foram obtidas 69.004 publicações. Foram detectados 46 sub-grupos emergentes concentrados nas temáticas: análise de custos ambientais e a relação de biocombustíveis com a agricultura, etanol de segunda geração e suas tecnologias, biodiesel, gasogênio, bio-gás, bio-hidrogênio e suas tecnologias, bioferinaria, células de combustíveis, microalgas e tecnologias de terceira geração. Dentre os sub-grupos emergentes em bioenergia os estudos sobre microalgas e tecnologias de terceira geração são os que surgem dentre os emergentes. Os resultados demonstram ainda que estudos sobre bioetanol de segunda geração representam o maior volume de publicação, ganhando a frente a partir do ano 2008. Na análise sobre empreendedorismo verificou-se que este não é um campo de pesquisa emergente, mas sim um campo em crescimento onde os novos estudos são contribuições incrementais baseadas nos trabalhos pioneiros, geralmente publicados nas décadas de 1980 e 1990. Conclui-se que o método utilizado, quando em sua versão original, não foi eficiente para detectar linhas de pesquisas em redes com grande quantidades de vértices, sendo necessário re-aplicar o método para encontrar grupos com menor nível de agregação. Tal intervenção implica que o método passa a necessitar da intervenção de um pesquisador para determinar se o nível de agregação dos grupos é elevado, e quando mais de dois procedimentos de agrupamento sejam aplicados ainda precisa-se definir quais sub-grupos serão re-agrupados. Contudo, o pesquisador não precisa ser especialista no campo de pesquisa estudado, pois a análise é feita a partir da evolução e da homogeneidade dos grupos e sub-grupos encontradosAbstract: This dissertation seeks to identify emerging lines of research by employing the computational approach based on network analysis as proposed by Shibata et al. (2008). The method came out as an alternative to carry out analyses without requiring intervention of experts in the researched area. We assessed the method performance by using it to detect trends in two networks, one with large number of publications, strong multidisciplinary connections and related to bioenergy industry; another in the field of social science and poorly connected with industry (entrepreneurship). The analysis of scientific publications in bioenergy comprised 69.004 publications. We identified 46 emerging sub-groups focused on assessment of environmental costs and the relationship of biofuels and farming, second-generation ethanol and related technologies, biodiesel, syngas, biogas, bio-hydrogen and related technologies, bio-refining, fuel cells, microalgae and third-generation technologies. Microalgae and third-generation technology are the most prominent emerging sub-groups in the bioenergy field. Yet, results show that research on second-generation bioethanol has been accounting for the largest number of publications since 2008. We also found that entrepreneurship is not an emergent research field but an expanding one, with publications broadly based on pioneer studies from 1980s and 1990s without much groundbreaking innovation. We conclude that the original version of the method isn¿t efficient to reveal emerging lines of research from networks with large amounts of vertices. It was necessary to re-run the method to find clusters with lower level of aggregation. This implies that the method requires intervention of a researcher to determine if aggregation level is too high. Besides, even if more than two clustering procedures are employed it is still needed to define which sub-groups will be re-clustered. Therefore, the researcher doesn¿t need to be an expert in the field of study, since the analysis is based on the evolution and homogeneity of the detected clusters and sub-clustersDoutoradoDesenvolvimento Economico, Espaço e Meio AmbienteDoutor em Desenvolvimento Economico006541/2014-03CAPE

Base intelectual de la fisioterapia a través del análisis de cocitación de documentos (1983-2009)

INTRODUCCIÓN Y OBJETIVO: Los análisis de cocitación de documentos, acompañados del uso de herramientas de minería de datos y de generación de grafos de red, consiguen la visión conjunta de miles de documentos citantes y una cantidad exponencial de referencias citadas, y permiten identificar la base intelectual de una disciplina o especialidad. Consideramos que uno de los retos importantes de la Fisioterapia en el siglo XXI dentro del actual marco científico, académico y clínico, debe orientarse hacia la definición clara de su base y de su estructura intelectual. En consecuencia, y dada la escasa cobertura bibliográfica específica en este ámbito de conocimiento, nos planteamos conocer las características y el desarrollo de la base intelectual de la Fisioterapia en las últimas décadas. MÉTODO: Se realizó un estudio observacional, longitudinal y retrospectivo, de corte bibliométrico. Se seleccionó como dominio de conocimiento la base intelectual de la Fisioterapia a través de las revistas ¿Physical Therapy¿, ¿Physiotherapy¿ y ¿Australian Journal of Physiotherapy¿, y como unidad de análisis las cocitaciones realizadas en los artículos publicados en estas revistas entre los años 1983 y 2009. Se recuperaron 7041 artículos, que aportaron 105687 citaciones válidas para su análisis de la base de datos Science Citation Index. Se utilizó como herramienta de análisis la aplicación Citespace II v.2.2.R9. El análisis se realizó sobre tres periodos (décadas naturales) y se concretó en subperiodos de un año, con la extracción de los 30 nodos más relevantes por año. Los datos se normalizaron con el algoritmo ¿coseno de Salton¿. Se realizó un análisis de regresión de ajuste curvilíneo para identificar el modelo de red para cada década. Se calcularon varios indicadores relacionados con la estructura de la red (densidad de la red, proporción de nodos, frecuencia de citación, centralidad de intermediación, tipo de documento y tipo de revista) y con la influencia sobre la estructura de los fenómenos temporales (año de publicación, burst y sigma). Se realizó un análisis de clústeres temáticos mediante el algoritmo de clusterización espectral. Las agrupaciones se etiquetaron con términos extraídos automáticamente de los títulos de los artículos citantes mediante los algoritmos tf*idf y log-likelihood ratio y se codificaron según un sistema de clasificación con cuatro dimensiones (área de especialidad, intención principal, patología e intervención). Finalmente se generó una visualización del grafo de la red fusionada de todos los subperiodos para cada década. RESULTADOS Y CONCLUSIONES: La formación de las redes mostró la evolución de una disciplina joven en la década de 1980 hacia una red de citación correspondiente con una disciplina más madura en el último periodo. El análisis de los indicadores estructurales aportó que los clásicos de citación y los documentos con una posición estratégica en Fisioterapia corresponden con documentos metodológicos en las tres décadas, junto con un papel destacado por parte de documentos relacionados con la valoración física en las primeras décadas, con la terapia manual en las dos últimas, y con documentos relacionados con la práctica basada en la evidencia y la prevención de caídas en el anciano en el último periodo. Además, los documentos más citados en la Fisioterapia fueron los documentos de revista, especialmente de otras áreas. Respecto a los indicadores temporales se encontró una estabilidad en la obsolescencia de la literatura utilizada en Fisioterapia, mientras que los documentos con mayor potencial transformador de su base intelectual coincidieron con los trabajos de Rothstein (1985 y 1991), la Guía de Práctica Clínica de la APTA (2001) y, especialmente, la Clasificación Internacional del Funcionamiento, la Discapacidad y la Salud de la OMS (2001). Por último, el análisis de los clústeres temáticos mostró un mayor desarrollo de las áreas de musculoesquelético y neurología, con un propósito principal centrado en el análisis de los sistemas de medición y su aplicación en la evaluación y el diagnóstico en Fisioterapia, que ha evolucionado desde un enfoque en la valoración física hacia un marcado interés en la valoración de la discapacidad y la funcionalidad con el uso de escalas y cuestionarios. Las patologías más vinculadas a la base de conocimiento de la Fisioterapia fueron la hemiplejia del adulto y la lumbalgia, mientras que el ejercicio terapéutico en las tres décadas, junto con la electroterapia en las dos primeras y la terapia manual en las dos últimas, fueron las intervenciones más destacadas.Terapia y Rehabilitació