Refine
Document Type
- Article (850)
- Conference Proceeding (821)
- Part of a Book (194)
- Working Paper (30)
- Book (29)
- Report (21)
- Doctoral Thesis (18)
- Part of Periodical (17)
- Review (5)
- Anthology (2)
Has Fulltext
- yes (1989) (remove)
Is part of the Bibliography
- yes (1989)
Institute
- Informatik (667)
- ESB Business School (585)
- Technik (337)
- Life Sciences (248)
- Texoversum (125)
- Zentrale Einrichtungen (9)
Publisher
- Springer (239)
- IEEE (229)
- Hochschule Reutlingen (174)
- Elsevier (134)
- MDPI (76)
- Gesellschaft für Informatik (61)
- Springer Gabler (47)
- ACM (38)
- De Gruyter (33)
- Wiley (32)
In the last decade, numerous learning factories for education, training, and research have been built up in industry and academia. In recent years learning factory initiatives were elevated from a local to a European and then to a worldwide level. In 2014 the CIRP Collaborative Working Group (CWG) on Learning Factories enables a lively exchange on the topic "Learning Factories for future oriented research and education in manufacturing". In this paper results of discussions inside the CWG are presented. First, what is meant by the term Learning Factory is outlined. Second, based on the definition a description model (morphology) for learning factories is presented. The morphology covers the most relevant characteristics and features of learning factories in seven dimensions. Third, following the morphology the actual variance of learning factory manifestations is shown in six learning factory application scenarios from industrial training over education to research. Finally, future prospects of the learning factory concept are presented.
The physicochemical properties of synthetically produced bone substitute materials (BSM) have a major impact on biocompatibility. This affects bony tissue integration, osteoconduction, as well as the degradation pattern and the correlated inflammatory tissue responses including macrophages and multinucleated giant cells (MNGCs). Thus, influencing factors such as size, special surface morphologies, porosity, and interconnectivity have been the subject of extensive research. In the present publication, the influence of the granule size of three identically manufactured bone substitute granules based on the technology of hydroxyapatite (HA)-forming calcium phosphate cements were investigated, which includes the inflammatory response in the surrounding tissue and especially the induction of MNGCs (as a parameter of the material degradation). For the in vivo study, granules of three different size ranges (small = 0.355–0.5 mm; medium = 0.5–1 mm; big = 1–2 mm) were implanted in the subcutaneous connective tissue of 45 male BALB/c mice. At 10, 30, and 60 days post implantationem, the materials were explanted and histologically processed. The defect areas were initially examined histopathologically. Furthermore, pro- and anti-inflammatory macrophages were quantified histomorphometrically after their immunohistochemical detection. The number of MNGCs was quantified as well using a histomorphometrical approach. The results showed a granule size-dependent integration behavior. The surrounding granulation tissue has passivated in the groups of the two bigger granules at 60 days post implantationem including a fibrotic encapsulation, while a granulation tissue was still present in the group of the small granules indicating an ongoing cell-based degradation process. The histomorphometrical analysis showed that the number of proinflammatory macrophages was significantly increased in the small granules at 60 days post implantationem. Similarly, a significant increase of MNGCs was detected in this group at 30 and 60 days post implantationem. Based on these data, it can be concluded that the integration and/or degradation behavior of synthetic bone substitutes can be influenced by granule size.
With the expansion of cyber-physical systems (CPSs) across critical and regulated industries, systems must be continuously updated to remain resilient. At the same time, they should be extremely secure and safe to operate and use. The DevOps approach caters to business demands of more speed and smartness in production, but it is extremely challenging to implement DevOps due to the complexity of critical CPSs and requirements from regulatory authorities. In this study, expert opinions from 33 European companies expose the gap in the current state of practice on DevOps-oriented continuous development and maintenance. The study contributes to research and practice by identifying a set of needs. Subsequently, the authors propose a novel approach called Secure DevOps and provide several avenues for further research and development in this area. The study shows that, because security is a cross-cutting property in complex CPSs, its proficient management requires system-wide competencies and capabilities across the CPSs development and operation.
Implementation of product-service systems (PSS) requires structural changes in the way that business in manufacturing industries is traditionally conducted. Literature frequently mentions the importance of human resource management (HRM), since people are involved in the entire process of PSS development and employees are the primary link to customers. However, to this day, no study has provided empirical evidence whether and in what way HRM of firms that implement PSS differs from HRM of firms that solely run a traditional manufacturing based business model. The aim of this study is to contribute to closing this gap by investigating the particular HR components of manufacturing firms that implement PSS and compare it with the HRM of firms that do not. The context of this study is the fashion industry, which is an ideal setting since it is a mature and highly competitive industry that is well-documented for causing significant environmental impact. PSS present a promising opportunity for fashion firms to differentiate and mitigate the industry’s ecological footprint. Analysis of variance (ANOVA) was conducted to analyze data of 102 international fashion firms. Findings reveal a significant higher focus on nearly the entire spectrum of HRM components of firms that implement PSS compared with firms that do not. Empirical findings and their interpretation are utilized to propose a general framework of the role of HRM for PSS implementation. This serves as a departure point for both scholars and practitioners for further research, and fosters the understanding of the role of HRM for managing PSS implementation.
In recent years the share economy has gained widespread success across different industries. Since small firms and new ventures obtain fewer resources, an increased focus on service allows them to differentiate and compete with cost pressure in traditionally manufacturing based industries. There still is a lack of understanding how these firms manage to successfully shift towards service-oriented business models. This paper adopts a dynamic capabilities approach to examine the particular microfoundations that underlie sensing, seizing and reconfiguring dynamic capabilities of early-stage service firms within a traditional retail market. The context of this study is the fashion industry. It is an ideal setting since it is characterized by severe competition, short life cycles, strong cost pressure and high volatility. There are few but increasing examples of entrepreneurial initiatives that try to compete by providing offers to resell, rent or swap clothes. Qualitative data of five early stage fashion ventures is analyzed. Findings reveal that the ability to develop and maintain long-term relationships is essential. It has also been found crucial to acquire knowledge from external network partners, delegate tasks and share information. Furthermore, skills for interacting with customers and adopting consumer feedback are critical. This study provides empirical evidence of dynamic capabilities of early-stage firms and contributes to knowledge on the factors that facilitate servitization in traditionally manufacturing based industries. For practitioners, the presented microfoundations provide a framework of critical tasks that allow them to develop and maintain a service oriented business model.
Venture capital and the innovative power of a state : econometric study including Google data
(2015)
This article focuses on venture capital investments and the innovative power of a state defined by its public infrastructure. The economic implications are evaluated by estimating several panel regression models. The novelty is twofold: on the one hand the research approach and on the other hand the new data set. The data ranges from 1995 to 2014 and consists of 10 European countries plus the US and Canada. For the first time we include Google search data on Venture Capital. The results show a significant increase in Venture Capital is mainly determined by economic conditions such as real GDP growth. The impact of the innovative power of a state is not significant. We find that Google data is positively related and significant in respect to Venture Capital investments too. Consequently, we confirm that private business investments cannot be created by government policy alone rather via solid macroeconomic conditions.
This study is about estimating the reproducibility of finding palpation points of three different anatomical landmarks in the human body (Xiphoid Process and the 2 Hip Crests) to support a navigated ultrasound application. On 6 test subjects with different body mass index the three palpation points were located five times by two examiners. The deviation from the target position was calculated and correlated to the fat thickness above each palpation point. The reproducibility of the measurements had a mean error of ≈13.5 mm +- 4 mm, which seems to be sufficient for the desired application field.
Different types of raw cotton were investigated by a commercial ultraviolet-visible/near infrared (UV-Vis/NIR) spectrometer (210–2200 nm) as well as on a home-built setup for NIR hyperspectral imaging (NIR-HSI) in the range 1100–2200 nm. UV-Vis/NIR reflection spectroscopy reveals the dominant role proteins, hydrocarbons and hydroxyl groups play in the structure of cotton. NIR-HSI shows a similar result. Experimentally obtained data in combination with principal component analysis (PCA) provides a general differentiation of different cotton types. For UV-Vis/NIR spectroscopy, the first two principal components (PC) represent 82 % and 78 % of the total data variance for the UV-Vis and NIR regions, respectively. Whereas, for NIR-HSI, due to the large amount of data acquired, two methodologies for data processing were applied in low and high lateral resolution. In the first method, the average of the spectra from one sample was calculated and in the second method the spectra of each pixel were used. Both methods are able to explain ≥90 % of total variance by the first two PCs. The results show that it is possible to distinguish between different cotton types based on a few selected wavelength ranges. The combination of HSI and multivariate data analysis has a strong potential in industrial applications due to its short acquisition time and low-cost development. This study opens a novel possibility for a further development of this technique towards real large-scale processes.
Hyperspectral imaging and reflectance spectroscopy in the range from 200–380 nm were used to rapidly detect and characterize copper oxidation states and their layer thicknesses on direct bonded copper in a non-destructive way. Single-point UV reflectance spectroscopy, as a well-established method, was utilized to compare the quality of the hyperspectral imaging results. For the laterally resolved measurements of the copper surfaces an UV hyperspectral imaging setup based on a pushbroom imager was used. Six different types of direct bonded copper were studied. Each type had a different oxide layer thickness and was analyzed by depth profiling using X-ray photoelectron spectroscopy. In total, 28 samples were measured to develop multivariate models to characterize and predict the oxide layer thicknesses. The principal component analysis models (PCA) enabled a general differentiation between the sample types on the first two PCs with 100.0% and 96% explained variance for UV spectroscopy and hyperspectral imaging, respectively. Partial least squares regression (PLS-R) models showed reliable performance with R2c = 0.94 and 0.94 and RMSEC = 1.64 nm and 1.76 nm, respectively. The developed in-line prototype system combined with multivariate data modeling shows high potential for further development of this technique towards real large-scale processes.
Due to its wide-ranging endocrine functions, adipose tissue influences the whole body’s metabolism. Engineering long-term stable and functional human adipose tissue is still challenging due to the limited availability of suitable biomaterials and adequate cell maturation. We used gellan gum (GG) to create manual and bioprinted adipose tissue models because of its similarities to the native extracellular matrix and its easily tunable properties. Gellan gum itself was neither toxic nor monocyte activating. The resulting hydrogels exhibited suitable viscoelastic properties for soft tissues and were stable for 98 days in vitro. Encapsulated human primary adipose-derived stem cells (ASCs) were adipogenically differentiated for 14 days and matured for an additional 84 days. Live-dead staining showed that encapsulated cells stayed viable until day 98, while intracellular lipid staining showed an increase over time and a differentiation rate of 76% between days 28 and 56. After 4 weeks of culture, adipocytes had a univacuolar morphology, expressed perilipin A, and secreted up to 73% more leptin. After bioprinting establishment, we demonstrated that the cells in printed hydrogels had high cell viability and exhibited an adipogenic phenotype and function. In summary, GG-based adipose tissue models show long-term stability and allow ASCs maturation into functional, univacuolar adipocytes.
