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The use of augmented reality (AR) in outbound logistics is associated with potentially strong stimuli for cost savings and throughput time. Nevertheless, the benefits of AR compared to conventional methods require a holistic analysis for investment decision making. Until now, research has only assessed case-study-related potentials and selected aspects of the technology. This paper answers the following research questions: How can the economic efficiency of AR in the packing process be quantified by utilizing a holistic model of value drivers? How can AR be technically implemented for packing processes in outbound logistics? What economic profit results from the use of AR technology in a case company’s packing process?
The presented model enables the investment decision to be supported based on economic value added (EVA), thereby providing an assessment of value drivers in packing systems. Cost drivers are identified on the basis of the Supply Chain Operations Reference (SCOR) process model. The technical and economic validation of the model was carried out by means of an empirical study: Expert interviews were conducted for validating the model elements. Data collection by a prototype at a mechanical-engineering company was used to calculate the value contribution. The mapping of cause-effect relationships within the framework of EVA driver trees has proven itself in both the expert interviews and the prototype validation. The field experiment at the case company demonstrated a positive value contribution of AR, in particular regarding employee productivity, length and variance of throughput time, quality aspects, volume utilization, and quantity of packing material used.
Adaptive laser resonators with deformable MOEMS mirrors under closed-loop control are discussed and experimental results are presented. The requirements for deformable mirrors and for closed-loop control systems of these mirrors are analyzed. Several deformable mirrors have been characterized and the results are presented. Currently available membrane mirrors deform under laser load and need further development before they can be used for aberration correction of solid state lasers above some tens of Watts. Nevertheless, the results are encouraging and the requirements are within reach of currently available technology. Finally, we demonstrate an Nd.YVO4-laser with a closed-loop adaptive resonator and more than 6 W of output power. The closed-loop system was able to compensate artificially introduced aberrations from a phase plate.
Gazelle: Ganzheitliche Regelung von Biogasanlagen zur Flexibilisierung und energetischen Optimierung
(2021)
Background: Modern healthcare devices can be connected to computer networks and many western healthcareinstitutions run those devices in networks. At the same time, cyber attacks are on the rise and there is evidence thatcybercriminals do not spare critical infrastructure such as major hospitals, even if they endanger patients. Intuitively,the more and closer connected healthcare devices are to public networks, the higher the risk of getting attacked.
Methods: To asses the current connectivity status of healthcare devices, we surveyed the field of German hospitalsand especially University Medical Center UMCs.
Results: The results show a strong correlation between the networking degree and the number of medical devices.The average number of medical devices is 25.150, with a median of networked medical devices of 3.600. Actual keyusers of networked medical devices are the departments Radiology, Intensive Care, Radio-Oncology RO, NuclearMedicine NUC, and Anaesthesiology in the group of UMCs. In the next five years, the usage of networked medicaldevices will increase significantly in the departments of Surgery, Intensive Care, and Radiology. We detected a strongcorrelation between the degree of connectivity and the likelihood of being attacked.The survey answers regarding the cyber security status reveal a lack of security basics in some of the inquiredhospitals. We did discover successful attacks in hospitals with separated or subsidiary departments. A fusion ofcompetencies on an organizational level facilitates the right behavior here. Most hospitals rated themselvespredominantly positively in the self-assessment but also stated the usefulness of IT security insurance.Conclusions:Concluding our results, hospitals are already facing the consequences of omitted measures within theirgrowing pool of medical devices. Continuously relying on historically grown structures without adaption and trustingmanufactures to solve vectors is a critical behavior that could seriously endanger patients.
In-depth analysis of customer journeys to broaden the understanding of customer behaviors and expectations in order to improve the customer experience is considered highly relevant in modern business practices. Recent studies predominantly focus on retrospective analysis of customer data, whereas more forward-directed concepts, namely predictions, are rarely addressed. Additionally, the integration of robotic process automation (RPA) to potentially increase the efficiency of customer journey analysis is not discussed in the current field of research. To fill this research gap, this paper introduces “customer journey mining”. Process mining techniques are applied to leverage digital customer data for accurate prediction of customer movements through individual journeys, creating valuable insights for improving the customer experience. Striving for improved efficiency, the potential interplay of RPA and customer journey mining is examined accordingly. The research methodology followed is based on a design science research process. An initially defined customer journey mining artifact is operationalized through an illustrative case study. This operationalization is achieved by analyzing a log file of an online travel agency functioning as an orientation for researchers and practitioners while also evaluating the initially defined framework. The data is used to train seven distinct prediction models to forecast the touchpoint a customer is most likely to visit next. Gradient-boosted trees yield the highest prediction accuracy with 43.1%. The findings further indicate technical suitability for RPA implementation, while financial viability is unlikely.
Camera based path planning for low quantity - high variant manufacturing with industrial robots
(2019)
The acquisition costs for industrial robots have been steadily decreasing in past years. Nevertheless, they still face significant drawbacks in the required effort for the preparation of complex robot tasks which causes these systems to be rarely present so far in small and medium-sized enterprises (SME) that focus mainly on small volume, high variant manufacturing. In this paper, we propose a camera-based path planning framework that allows the fast preparation and execution of robot tasks in dynamic environments which leads to less planning overhead, fast program generation and reduced cost and hence overcomes the major impediments for the usage of industrial robots for automation in SMEs with focus on low volume and high variant manufacturing. The framework resolves existing problems in different steps. The exact position and orientation of the workpiece are determined from a 3D environment model scanned by an optical sensor. The so retrieved information is used to plan a collision-free path that meets the boundary conditions of the specific robot task. Experiments show the potential and effectiveness of the the framework presented here by evaluating a case study.
Biogas Benchmark Münsterland
(2019)
Optimierung einer Feinseparation für die Aufbereitung von Rindergülle und Gärresten - OptiSep
(2019)
Virtual reality (VR) is starting to realize some of its promise as a tool to improve training effectiveness. However, research on VR for training and development is limited. Existing theories and models relating to organizational training and learning are infrequently used in the VR literature. A greater understanding of why VR works in the training context would help training designers create effective programs that leverage this continuously developing technology. This paper provides a typology of VR technologies specifically relevant to HR and integrates HR training frameworks and theory into findings on VR training from these other literatures. We specifically focus on immersive VR technology and seek to better understand reasons for the effectiveness of VR technologies for both training and assessment. We review findings, integrate related streams of research, and offer guideposts for those contemplating VR implementation in four important areas: training reactions in a VR context, VR-specific learning outcomes, opportunities for assessment using VR, and the effect of VR on training transfer. We conclude the paper by identifying a VR-training agenda for HR researchers.
This paper deals with the issue of automating the
process of machine learning and analyzing bio-datasets. For this
a user-friendly website has been developed for the interaction
with the researchers. On this website it is possible to upload
datasets and to share them, if desired, with other scientists. The
uploaded data can also be analyzed by various methods and
functions. The signals inside these datasets can also be visualized.
Furthermore several algorithms have been implemented to create
machine learning models with the uploaded data. Based on these
generated models new data can be classified or calculated. For all
these applications the simplest possible handling was
implemented to make the website available to all interested
researchers.
Laser shock peening is a new and important surface treatment technique that can enhance the mechanical properties of metal materials. Normally, the nanosecond laser with pulse-width between 5 ns and 20 ns is used to induce a high-pressure shock wave that can generate plastic deformation in the top layer of metals. The femtosecond laser shock peening in the air has been studied recently, which can induce higher pressure shock wave than that of traditional nanosecond laser shock peening in a very short time. The NiTi alloy is processed by femtosecond laser shock peening, then a nanoindentation device is used to measure its surface hardness and residual stress. The hardness results of NiTi alloy before and after treatment show that the femtosecond laser shock peening can increase the hardness of NiTi alloy, which also shows that the femtosecond laser can be used to perform laser shock peening on NiTi alloy without coating.
The experiment study presents the influence of femtosecond laser shock peening (FsLSP) without a protective layer in the air on the surface hardness and surface mechanical property of NiTi shape memory alloy. Femtosecond laser shock peening is a new possibility of direct laser ablation without any protective layer under atmospheric conditions, which can produce intense shock waves with low pulse energy in the air. The average surface roughness values of the NiTi alloy samples were measured, because the surface roughness may affect its friction resistance. The results showed that the surface roughness of NiTi increased after femtosecond laser shock peening treatment. In comparison with the initial state, the coefficient of friction decreased and surface microhardness increased after femtosecond laser shock peening treatment with different FsLSP parameters. This improvement of wear properties may be attributed to the enhancement of surface microhardness and surface titanium oxide layer induced by the shock wave and laser ablation during FsLSP treatment.
Quick UDP Internet Connections (QUIC) is a novel transport protocol introducing known features in a new protocol design. To investigate these features and the design, we developed a QUIC implementation in the INET simulation model suite.
In this paper, we describe that implementation, its validation and a result achieved using the simulation model. The result shows the negative impact on throughput, when raising the acknowledgment ratio. We propose a solution and describe how it solves the issue.
A data sender in an IP based network is only capable to efficiently use a network path if it knows the packet size limit of the path, i.e., the Path Maximum Transmission Unit (PMTU). The IETF recently specified a PMTU discovery framework for transport protocols like QUIC. This paper complements this specification by presenting a search algorithm. In addition, it defines several metrics and shows results of analyses for the algorithm with various PMTU candidate sequences using these metrics. We integrated the PMTU discovery with our algorithm into a QUIC simulation model. This paper describes the integration and presents measurements obtained by simulations.
A communication over an Internet Protocol (IP) based network fails if an endpoint sends packets that are too big to reach their destination and if the sender is unable to detect that. The node on the path that drops these packets should respond with a Packet Too Big (PTB) message. However, multiple scenarios exist in which the sender will not receive a PTB message. Even if it does, it refrains from using the information in case it suspects that a potential attacker forged the message. In particular, we are not aware of any implementation of the secure transport protocol QUIC (e.g., used by HTTP/3) that processes PTB messages. In this paper, we present a novel parameterizable PTB detection algorithm for reliable transport protocols that does not depend on PTB messages. We further describe how to integrate our algorithm into QUIC, present results from an evaluation using the algorithm within a QUIC simulation model and, based on these results, suggest concrete parameter values.
Industrialisierung im Krankenhaus : Spezielle Controllingprobleme der interdisziplinären Notaufnahme
(2009)
Over the past 5 years we have developed a new type of unimorph deformable mirror. The main advantages of this mirror technology are · very low surface scattering due to the use of superpolished glass · excellent coatings, even suitable for high power lasers, can be applied · active diameter of the mirrors can be between 10 mm and 100 mm · large strokes can be achieved even for small mirror diameters · integrated monolithic tip/tilt functionality based on a spiral arm design We have modeled these mirrors by analytical models as well as by the finite element method. This allows us to quickly design new mirrors tailored to specific applications. One example is a mirror for laser applications that has a diameter of 10 mm and can achieve a stroke in defocus mode of 5 μm. The stroke for these mirrors scales as the square of the mirror diameter, meaning that we can achieve, for example, a stroke of 125 μm for a mirror of 50 mm diameter. We will present design criteria and tradeoffs for these mirrors. We characterize our mirrors by the maximum stroke they can deliver for various Zernike modes, under the boundary condition that the Zernike mode has to be created with a certain fidelity, usually defined by the Maréchal criterion.
Novel unimorph deformable mirror with monolithic tip-tilt functionality for solid state lasers
(2011)
We present a new type of unimorph deformable mirror with monolithic tip-tilt functionality. The tip-tilt actuation is based on a spiral arm design. The mirror will be used in high-power laser resonators for real-time intracavity phase control. The additional tip-tilt correction with a stroke up to 6 μm simplifies the resonator alignment significantly. The mirror is optimized for a laser beam footprint of about 10 mm. We have modeled and optimized this mirror by finite element calculations and we will present design criteria and tradeoffs for this mirrors. The mirror is manufactured from a super-polished glass substrate with very low surface scattering and excellent dielectric coating.
It has been shown that the beam quality and the efficiency of high-power solid-state lasers could be enhanced by the use of deformable mirrors in order to compensate for optical aberrations. An intracavity compensation requires a deformable mirror which is capable of handling very high laser intensities. The active diameter of the deformable mirror should be a few millimeters in order to match typical fundamental mode laser beam diameters. There is a wide variety of commercially available deformable mirrors, but neither meets all requirements.
We present a novel unimorph deformable mirror with a diameter of only 10 mm that will be used in adaptive resonators of high power solid state lasers. The relationship between applied voltage and deformation of a unimorph mirror depends on the piezoelectric material properties, layer thicknesses, boundary conditions, and the electrode pattern. An analytical equation for the deflection of the piezoelectric unimorph structure is derived, based on the electro-elastic and thin plate theory. The validity of the proposed analytical model has been proven by numerical finite-element modelling and experimental results. Our mirror design has been optimized to obtain the highest possible stroke and a high resonance frequency.
We have developed a new type of unimorph deformable mirror, designed to correct for low-order Zernike modes. The mirror has a clear optical aperture of 50 mm combined with large peak-to-valley Zernike amplitudes of up to 35 μm. Newly developed fabrication processes allow the use of prefabricated super-polished and coated glass substrates. The mirror's unique features suggest the use in several stronomical applications like the precompensation of atmospheric aberrations seen by laser beacons and the use in woofer-tweeter systems. Additionally, the design enables an efficient correction of the inevitable wavefront error imposed by the floppy structure of primary mirrors in future large space-based telescopes. We have modeled the mirror by using analytical as well as finite element models. We will present design, key features and manufacturing steps of the deformable mirror.
Der Spreadsheet Energy System Model Generator (SESMG) ist ein Werkzeug zur Modellierung und Optimierung von (urbanen) Energiesystemen. Der SESMG hat eine browserbasierte grafische Benutzeroberfläche, eine tabellenbasierte Dateneingabe und eine ausführliche Dokumentation, was einen einfachen Einstieg ermöglicht. Zudem erfordern die Installation und Anwendung keine Programmierkenntnisse. Im SESMG sind verschiedene Modellierungsmethoden implementiert, wie z. B. die Anwendung des Multi-Energie-System-Ansatzes, die multikriteriale Optimierung, modellbasierte Methoden zur Reduktion des Rechenaufwands sowie die automatisierte Erstellung von räumlich hoch aufgelösten Energiesystemmodellen. Somit können urbane Energiesysteme mithilfe des SESMGs mit vergleichsweise geringem Aufwand, aber unter Berücksichtigung einer Vielzahl von Parametern und Randbedingungen, modelliert und optimiert werden.
Hintergrund: Chronischen kardiometabolischen Krankheiten ist gemein, dass sie maßgeblich durch einen ungesunden Lebensstil (e.g. körperliche Inaktivität, hyperkalorische Ernährung mit ungünstigen Verzehrsmustern, chronische Stresszustände) begünstigt werden. Vor diesem Hintergrund ist es von großem Interesse, Interventionen zu entwickeln, die die Implementierung eines gesundheitsförderlichen Lebensstils ermöglicht.
Fragestellung: Ist ein gemeinschaftsbasiertes Interventionsprogramm zur Förderung eines gesunden Lebensstils geeignet, das kardiometabolische Risikoprofil zu verbessern?
Methoden: Die kontrollierte Interventionsstudie umfasst 6 Messzeitpunkte über den Zeitraum von insgesamt 24 Monaten. Für die Interventionsgruppe (N = 107) fanden individuelle Gesundheitscoachings sowie ein zehnwöchiges intensives Lebensstilprogramm mit anschließenden monatlichen Alumni-Treffen statt. Die Kontrollgruppe (N = 45) erhält keine Behandlung. Neben anthropometrischen, Vital- und Laborparametern zur Bestimmung des metabolischen Risikoprofils wurde das subjektiv wahrgenommene Stresslevel (PSS-10) erfasst. Ergebnisse: Die Probanden der Interventionsgruppe zeigten eine Verbesserung des kardiovaskulären Risikoprofils nach 10 Wochen – während sich das Risikoprofil in der Kontrollgruppe nicht veränderte. Die Parameter näherten sich auch in der Interventionsgruppe im weiteren Studienverlauf bis zum Messzeitpunkt t4 (nach 12 Monaten) wieder den Ausgangswerten an, erreichten das Ausgangniveau jedoch zumeist nicht. Schlussfolgerung: Das gemeinschaftsbasierte Lebensstilprogramm ist geeignet, um das kardiovaskuläre Risikoprofil erwachsener Menschen positiv zu beeinflussen. Zukünftig sollte der Fokus auf die nachhaltige Etablierung gesundheitsförderlicher Verhaltensweisen gelegt werden, um einen erneuten Anstieg des Risikos nach Beendigung der Intensivphase zu vermeiden.
Hintergrund:
Im BMBF-geförderten Forschungsprojekt MigrAVE wurde neben einem Assistenzroboter zur Unterstützung autistischer Kinder im Rahmen verhaltenstherapeutischer Interventionen eine multilinguale Online-Informationsplattform zu ASS entwickelt. Die Inhalte wurden auf Basis einer Anforderungsanalyse und einer Bestandsaufnahme verfügbarer Lernmaterialien, Texte und Informationssammlungen ausgewählt und gestaltet.
Methodik:
Die als Prototyp entwickelte MigrAVE-Plattform ist in einen offen zugänglichen und einen Log-In-Bereich unterteilt.
Der offene Bereich beinhaltet umfangreiche Informationen zur Symptomatik, Diagnostik sowie zu evidenzbasierten Interventionsmöglichkeiten bei ASS.
Dazu kommt eine umfangreiche Sammlung an Links zu Kontaktstellen, Literatur, Social-Media-Kanälen, sozialrechtlichen Informationen sowie verwandten Forschungsprojekten. Die genannten Inhalte werden in deutscher und englischer Sprache präsentiert. Zudem sind Info-Videos in derzeit acht Sprachen (Deutsch, Englisch, Spanisch, Polnisch, Türkisch, Ukrainisch, Arabisch und Russisch) verfügbar. Der Log-In-Bereich richtet sich an Therapeuten und Eltern, die an verhaltenstherapeutischen Förderprogrammen teilnehmen und die Online-Ressourcen ergänzend nutzen können. In diesem Bereich sind eine vertiefende Einführung in die Grundlagen und die Anwendung der autismusspezifischen Verhaltenstherapie und eine große Auswahl an Arbeitsmaterialien zum Download verfügbar. Die Beschränkung dient einer reflektierten und supervidierten Nutzung im Rahmen qualifizierter Förderprogramme.
Der Plattform-Prototyp wurde mit Blick auf Zugänglichkeit und Relevanz der präsentierten Inhalte zu Gebrauchstüchtigkeit (Usability Evaluation) und Benutzererfahrung (User Experience) durchgeführt, um die Gütekriterien nach der ISO (Effektivität, Effizienz und Zufriedenheit) zu erheben.
Ergebnisse:
Die Ergebnisse der Evaluation zeigen eine positive Nutzerbewertung bezüglich Umfang, Informationsgehalt, Glaubwürdigkeit und Verständlichkeit. Aus der Evaluation ergaben sich in einer ersten Iteration Redesign- und Verfeinerungsarbeiten zum User-Interface sowie
Recherche- und Servicefunktionen. Eine praktische Nutzung als therapiebegleitende Ressource ist für 2024 im Frühinterventionsprogramm „Münsteraner Intensivprogramm für Kinder mit Autismus“ und kooperierenden Programmen beabsichtigt.
Schlussfolgerungen:
Der Prototyp für ein qualitätsgesichertes und mehrsprachiges internetgestütztes Informationsangebot zu ASS konnte erfolgreich entwickelt und evaluiert werden. Die Teilung in ein allgemein zugängliches Material einer- und spezifischen Therapiesupport für Familien, die sich in professioneller Betreuung befinden, andererseits erscheint als eine sinnvolle Konzeption.
In this study, we use a hybrid mode-locked external cavity diode laser with subsequent amplification and pulse compression. The system provides laser pulses of 440 fs width (assuming a sech² pulse shape) and 160 mW average output power at a repetition rate of 383.1 MHz. The laser oscillator consists of a double quantum well laser diode with a gain segment of 1080 μm length and an absorber element of 80 μm lengths. The chip’s back facet is covered with a high reflective coating, the front facet with an anti-reflective coating. The resonator itself is operated in a collimated geometry and folded by two dielectric mirrors. The used output coupler provides a transmission of 20 percent, which is coupled into a tapered amplifier. Two Faraday isolators are used to decouple the laser and the amplifier from any back reflections. Subsequently, the pulses are compressed using a single pass Martinez type pulse compressor …
Experimental and numerical study of transonic flow of an organic vapor past a circular cylinder
(2022)
BIM Interdisziplinär
(2018)