Modelling methodologies for quality assessment of 3D inkjet printed electronic products

Purpose of the Fraunhofer Direct Digital Manufacturing Conference is an intellectual exchange between researchers, enterprises and users of Additive Manufacturing technologies in order to gather the latest information about trends, progress, importance and the future potential of these technologies for industrial applications. The range of topics covers Product Development (incl. simulation, co-design, mass customization), Technologies (incl. bio-printing, hybrid processes, novel developments/visionary concepts, process chains for industrial production), Materials (incl. ceramics, bio-materials, multi-material approaches), Quality (incl. process/ part quality management) as well as further innovative and visionary approaches not fitting the range of topics above. Renowned international keynote speakers give insight into the latest trends and challenges in additive manufacturing in a variety of industry sectors, including biomedical, aerospace and automotive

Numerical analysis of droplet deposition in inkjet printed electronics assembly

In this paper, a computational approach for the analysis of microscale droplet impact dynamics is presented. The approach is intended to support a condition based monitoring system to enhance quality and reliability of inkjet printed electronics components. The Smoothed Particle Hydrodynamics (SPH) approach of Lucy and Gingold and Monaghan has been used as the basis for the model, with the δ-SPH terms of Marrone et al used to improve handling of the dynamic impact events and the gradient correction terms of Belytschko used to improve the accuracy of interface dynamics. Model validation has been performed through comparison against a macroscale dam break problem and through a microscale analysis designed to determine accurate surface tension-pressure behaviour based on the Young-Laplace relation. The model is used to assess impact of a single drop on a uniform surface and the three dimensional formation of multi-drop layers

The Early and Middle Pleistocene archaeological record of Greece : current status and future prospects

By applying a fieldwork-based, geoarchaeological approach, Tourloukis examines in this study the evidence from Greece within the framework of the earliest occupation of Europe. Although the Greek Peninsula lies within a core area of early hominin movements between Africa and Europe but also within Eurasia itself, the Lower Palaeolithic record of Greece remains as yet extremely poor. Chossing the scanty Greek record as a case-study, Tourloukis elaborates on a hitherto largely overlooked subject in the Eurasian Early-Middle Pleistocene archaeology: the role of geomorphic processes in biasing archaeological distribution patterns of early human presence. This study identifies the current status of the record, explains this status from a geoarchaeological and geomorphological perspective, and prospects its future enrichment. The analysis is carried-out on a landscape-scale and it assesses preservation potential in conjuction with archaeological visibility. Finally a conceptual model emerges that can assist in interpreting and/or predicting early Palaeolithic site locations in tectonically active settings, such as those of the Mediterranean Basin.LEI Universiteit LeidenState Scholarships Foundation (Greece)Human Origin

Proboscidea-Homo interactions in open-air localities during the Early and Middle Pleistocene of western Eurasia: a palaeontological and archaeolocigal perspective

In recent years, a significant number of Pleistocene localities with evidence of proboscidean exploita- tion by humans has been discovered, substantial- ly enriching our knowledge on Homo subsistence strategies and megafauna acquisition. In this study, we provide a synthesis of the evidence for Pro- boscidea-Homo interactions in Early and Middle Pleistocene open-air sites of western Eurasia with direct (e.g., presence of cut marks, proboscidean bone artifacts, fractures for marrow extraction) and indirect (e.g., association and refitting of lithic ar- tifacts, use-wear analysis) evidence of exploitation. Sex and ontogenetic age of butchered proboscide- ans are recorded, in order to assess possible human preferences. Furthermore, we investigate the role of large carnivores focusing on important renew- als in the carnivore guilds, and their significance in terms of carrion availability for scavenging and human-carnivore competition for access to food resources. By applying an ecomorphological/be- havioral approach, we examine the large carnivore community structure and dynamics, with empha- sis in the hunting strategies of large predators. Ad- ditionally, we aim to infer their possible role in the changes of early human subsistence strategies fo- cusing on proboscidean acquisition, and to explore the role of humans within the predatory guild. The ecological adaptations of the two common Middle Pleistocene proboscideans in Europe, the Europe- an straight-tusked elephant Palaeoloxodon antiquus and the steppe mammoth Mammuthus trogonthe- rii, are also evaluated. Finally, we discuss various aspects of the Homo bio-cultural evolution during the period under study, including developments in material culture and relevant inferences about hu- man social behavior.The symposium and the volume "Human-elephant interactions: from past to present" were funded by the Volkswagen Foundation

The lithic assemblages from the Palaeolithic survey research in the Megalopolis Basin, Greece

An intensive, target-oriented surface survey conducted in the Megalopolis basin during 2012-2013 led to the discovery of several Palaeolithic sites and findspots with lithics and faunal remains, including Marathousa-1, a Lower Palaeolithic open-air elephant-butchering site, dated to ca. 400-500 ka BP. This study presents the results from the techno-typological analysis of 413 lithic artefacts collected as surface or stratified finds during the survey research. The aim of the work is to evaluate the diachronic occupation of the area in relation to the lithic technologies used, the typology of the artefacts, and the raw materials exploited. It was possible to provide a chrono-cultural attribution of 167 artefacts, ranging from the Lower Palaeolithic to the Holocene, with a significant component of the collection attributed to the Middle Palaeolithic. Several diagnostic retouched tools allow us to infer that the open-air sites were occupied comparatively more intensively during the Middle Palaeolithic period. We also provide a detailed account of the lithic assemblage from Kavia cave, a previously unstudied site identified during the survey. The high frequency of artefacts pertaining to the Upper Palaeolithic in Kavia is in line with previously identified settlement and mobility patterns of the Peloponnese, where the occupation of caves becomes more intensive from the Upper Palaeolithic onward, as attested at the sites of Klissoura, Kephalari, and Franchthi. The Upper Palaeolithic component from Kavia Cave adds new data to a meagre sample of known sites from this period. The results from the typological and technological analysis of the lithic assemblages collected during the survey in Megalopolis support the conclusions of the basin's long-term and ongoing research, indicating a relatively continuous hominin presence during the Pleistocene

Optical dating of K-feldspar grains from Middle Pleistocene lacustrine sediment at Marathousa 1 (Greece)

Post-infrared infrared stimulated luminescence (pIRIR) measurements are reported for multiple aliquots of potassium-rich feldspar grains from sedimentary deposits at Marathousa 1 and Choremi Mine in the Megalopolis Basin in southern Greece. Ages were obtained for 9 samples from the deposits that over- and underlie as well as include the archaeological and palaeontological deposits at Marathousa 1. These sediments are sandwiched between lignite seams II and III and thought to represent sediment deposition during a single glacial period. A single age was obtained for a sample from Choremi mine. The equivalent dose estimates are based on a newly developed method presented elsewhere, and environmental dose rate determinations followed standard procedures. A specific focus of this paper is the determination of a representative estimate of time-averaged palaeo-water content of the organic and sand-rich deposits and the impact of porosity and compaction on these estimates. Ages are presented using two water content scenarios. These final ages have relatively large uncertainties, making it difficult to accurately assign deposition to a single oxygen isotope stage (OIS). Taking uncertainty into account, sediment deposition at Marathousa 1 occur sometime during OIS 12 and 11 and at Choremi mine during MIS 8. When combined with other proxy information, these results support the interpretation that the peat deposits (represented by lignite seams II and III) were deposited during warm interglacial periods, and that the intervening clastic materials were deposited during glacial periods. In this case, the ages are best interpreted as supporting deposition of sediments during MIS12. This is consistent with one of the proposed age models, but younger than the other

Similarity approach for reducing qualification tests of electronic components

Qualification analysis and reliability testing of electronic components represent a major activity in the process of development of electronic equipment. Electronics manufacturers have to adopt often costly test programmes to ensure qualification standards and reliability requirements are met. This paper details a novel similarity-based qualification approach for assessing expected reliability of electronic components, and in general electronic prod- ucts, as an alternative to conventional physical testing. The originality of this work is in the proposed approach which introduces a new way of qualifying electronic components based on similarity with previously assessed and qualified components. This novel approach has the potential to transform in a major way the current oper- ational practices in the industry, demanding at present substantial physical testing, by offering a complementary, “virtual qualification” route for addressing the cost and time challenges associated with qualification tests. A major achievement is the comprehensive and detailed demonstration of the proposed reliability qualification approach. Case studies on qualifying electronic components to the thermal loads induced by a particular post- manufacturing process widely adopted by high-reliability electronics sectors – the robotic hot solder dip (refinishing) process, and associated risks of thermo-mechanical damage are presented and discussed

Human-elephant interactions from past to present: an introduction

In this introductory chapter of the interdisciplinary volume “Human-elephant interactions: from past to present”, we provide the background and the main questions of the archaeological, paleoanthropological and ethnographic studies that examine this field of ​​research. In addition, we describe the objectives and the thematic sections of the book, and for each section we present the current status of investigations. Finally, we conduct a brief description of the chapters, presenting their subject and their main research results.The symposium and the volume "Human-elephant interactions: from past to present" were funded by the Volkswagen Foundation

Human-elephant interactions: from past to present

korrigierter Nachdruck, nur Änderungen im ImpressumIn recent decades, a significant number of Pleistocene (ca. 2.6 million years–10,000 years ago) open-air and cave sites yielding elephant or mammoth bones in direct association with hominin remains and/or lithic artifacts have been discovered in Eurasia, Africa and America. Many of them show strong evidence of acquisition and processing of proboscidean carcasses by early humans, leading scientists to interpret them as “elephant butchering sites”. Indeed, proboscidean exploitation by early Homo has been proposed to have been critical for Palaeolithic human lifeways, influencing not only their subsistence, but also other aspects of early human evolution and adaptations. The nature and degree of interactions between humans and elephants comprises an important field in palaeoanthropological studies since decades, but many questions remain still unanswered or partially explored. By bringing together research papers from the fields of Palaeolithic Archaeology, Palaeoanthropology, Palaeontology, Zooarchaeology, Geology, Ethnography and Nutrition Studies, the book systematically covers a diverse array of perspectives on elephant-human interactions across the world from the Pleistocene times until today. The volume includes 19 contributions and is organized into four thematic sections: 1) The Palaeolithic record, 2) A view of the evidence, 3) Elephants in past human nutrition, and 4) Ethnography – Human-elephant interactions in recent Africa. Collectively, the volume not only showcases the current state of knowledge, but also intends to provoke renewed interest for current and further research, and build an interdisciplinary and synthetic understanding of the significance of proboscideans throughout human evolution

Human-elephant interactions: from past to present

In recent decades, a significant number of Pleistocene (ca. 2.6 million years–10,000 years ago) open-air and cave sites yielding elephant or mammoth bones in direct association with hominin remains and/or lithic artifacts have been discovered in Eurasia, Africa and America. Many of them show strong evidence of acquisition and processing of proboscidean carcasses by early humans, leading scientists to interpret them as “elephant butchering sites”. Indeed, proboscidean exploitation by early Homo has been proposed to have been critical for Palaeolithic human lifeways, influencing not only their subsistence, but also other aspects of early human evolution and adaptations. The nature and degree of interactions between humans and elephants comprises an important field in palaeoanthropological studies since decades, but many questions remain still unanswered or partially explored. By bringing together research papers from the fields of Palaeolithic Archaeology, Palaeoanthropology, Palaeontology, Zooarchaeology, Geology, Ethnography and Nutrition Studies, the book systematically covers a diverse array of perspectives on elephant-human interactions across the world from the Pleistocene times until today. The volume includes 19 contributions and is organized into four thematic sections: 1) The Palaeolithic record, 2) A view of the evidence, 3) Elephants in past human nutrition, and 4) Ethnography – Human-elephant interactions in recent Africa. Collectively, the volume not only showcases the current state of knowledge, but also intends to provoke renewed interest for current and further research, and build an interdisciplinary and synthetic understanding of the significance of proboscideans throughout human evolution.The symposium and the volume "Human-elephant interactions: from past to present" were funded by the Volkswagen Foundation