Marc Wilke

Recent advances in digital holography [Invited]

This article presents an overview of recent advances in the field of digital holography, ranging from holographic techniques designed to increase the resolution of microscopic images, holographic imaging using incoherent illumination, phase retrieval with incoherent illumination, imaging of occluded objects, and the holographic recording of depth-extended objects using a frequency-comb laser, to the design of an infrastructure for remote laboratories for digital-holographic microscopy and metrology. The paper refers to current trends in digital holography and explains them using new results that were recently achieved at the Institute for Applied Optics of the University Stuttgart.

itom: an open source metrology, automation, and data evaluation software

Modern optical sensors and measurement systems usually are a powerful combination of optical elements, active hardware components like actuators or sensing devices as well as a sophisticated control software and data evaluation algorithms. In order to develop and operate such systems, it is necessary to have a flexible, intuitive, and fast underlying software framework that also allows for rapid prototyping of a sensor in a dynamic lab environment. This software must be able to control and communicate with all necessary hardware devices and has to provide all the highly performant evaluation, data, and image processing algorithms required. In this publication, we want to present the open source measurement and data evaluation software suite itom, which has been designed considering the denoted requirements and whose development began in 2011.

Remote laboratories for optical metrology: from the lab to the cloud

Abstract. The idea of remote laboratories is reviewed, and the potential of the approach on selected examples with special focus on the field of optical metrology is illustrated. The concept of remote metrology is extended beyond the simple exchange of data between distant laboratories and the remote access to experimental facilities embedded in modern educational concepts. We describe an architecture that provides the opportunity to communicate with and eventually control the physical setup of a remote metrology system. We show that such a concept can be implemented within cloud-computing environments, and may extend their current performance by the access to experimental facilities.

Detection of transport and age induced damages on artwork: an advanced concept

For the society it is of great interest to make cultural heritage accessible to the general public. The subsequent increase of museum loan services increases the risk of accelerated degeneration. Hence, in addition to the age related deterioration, transportation can be another source of damage. Despite modern packaging technologies, vibrations and environmental climate change can add up and damage the transported object. Besides obvious mechanical influencing quantities, a main concern is the detection of climate induced damages. Changes in the relative humidity cause inner strain, which may lead to defect formations and damages. White light fringe projection was applied to detect object changes due to variations of the relative humidity. First measurements indicated a sensitivity down to a relative humidity change of 6 %. Recently, the Stuppach Madonna, a painting by Matthias Grunewald (painted 1514 - 1516), was investigated with shearography after the return from an exhibition. The obtained shearograms revealed a variety of defects like bubbles, delaminations and tunnels caused by wood worms. Even the planking of the wooden panel and existing putty could be detected. This paper describes the first steps of a project with the aim of investigating and implementing a method to detect and classify transport related damages on works of art.

KEA - a Mathematical Knowledge Management System combining Web 2.0 with Semantic Web Technologies

We present a knowledge management system suggesting a combination of Web 2.0 and semantic Web technologies. With regard to the accumulation of knowledge as a consequence of the increasing amount of scientific publications, the demand for sophisticated knowledge management systems in the scientific education has increased lately. Above all, mathematical publications remain a major challenge, caused by the need for complicated analysis of natural language texts and mathematical formulas. The Web-based, mathematical knowledge management system KEA provides natural language processing techniques, and benefits from new Web technologies.

Remote laboratory for digital holographic metrology

Advances in information technology open up the potential of combining optical systems with net based infrastructures, allowing for remote inspection and virtual metrology. In this paper, we report our recent work on building a remote laboratory for digital holographic metrology. We describe the architecture and the techniques involved in setting up the remote controlling metrology system. Further consideration will be given to the integration into an advanced infrastructure for remote experimentation, data storage and publication. Some other important issues such as information security will not be addressed.

Managing Mathematical Texts with OWL and Their Graphical Representation

Mathematical knowledge contained in scientific digital publications poses a challenge for intelligent retrieval mechanisms. Many current approaches use statistical (e.g. Google) or natural language processing methods to find correlations in texts and annotate texts semantically. However both kinds of approaches face the problem of extracting and processing knowledge from mathematical equations. The presented system is based on natural language processing techniques, and benefits from characteristic linguistic structures defined by the language used in mathematical texts. It accumulates extracted information snippets from texts, symbols, and equations in knowledge bases. These knowledge bases provide the foundation for the information retrieval. This article describes the concepts and the prototypical technical implementation.

KEA - A Knowledge Management System for Mathematics

Information contained in mathematical digital writings creates new challenges for knowledge management systems because automated knowledge extraction from natural language texts is a technical challenge. However, mathematical texts possess a distinctive structure. KEA benefits from this structure, and extracts linguistic relations from texts, creates ontologies, and combines them to a knowledge base. This knowledge base is the core of an enhanced retrieval system. Responses of this system are user-adaptive text-based and visualized. Possible applications are mathematical encyclopaedias, context sensitive library search, intelligent book indexes and e-learning software.

Teachers need robotics-training, too

Since robotics holds a special fascination among all the technological fields – due to its cross-disciplinary approach as well as its popularity through movies and literature – this field is attracting even the interest of pupils and students who are normally more reserved and cautious towards technological areas. In particular, practical experiences have shown that out of all the different technological areas robotics has a very high motivation impact on women. Thus, robotics can also be utilized as an instrument to bridge the gender gap in technological areas and fields of natural sciences.

Enhancing technological literacy: Robotics in academic education of non-engineers

Robotics, in particular mobile robotics, holds a special fascination among all the technological fields: Starting with the first ldquoautomatonsrdquo of ancient times (Archytas of Tarent, Heron of Alexandria) and da Vincipsilas studies of androids to the modern heroes of movies and literature, robots (and in particular, humanoid robots) have always captivated the fantasy of human beings. Unsurprisingly, robotics is attracting even the interest of people who are normally more reserved and cautious towards technological fields of study. As a result, robotics is well suited to strengthen the interdisciplinary components of the academic education of all students, in particular also of students from nontechnological areas, in order to strengthen their technological interest and literacy.