Showing papers by "Weingarten Realty Investors published in 2013"

The SLS-Generated Soft Robotic Hand - An Integrated Approach Using Additive Manufacturing and Reinforcement Learning

Abstract: To develop a robotic system for a complex task is a time-consuming process. Merging methods available today, a new approach for a faster realization of a multi-finger soft robotic hand is presented here. This paper introduces a robotic hand with four fingers and 12 Degrees of Freedom (DoFs) using bellow actuators. The hand is generated via Selective Laser Sintering (SLS), an Additive Manufacturing method. The complex task execution of a specific action, i.e. the lifting, rotating and precise positioning of a handling-object with this robotic hand, is used to structure the whole development process. To validate reliable functionality of the hand from the beginning, each development stage is SLS-generated and the targeted task execution is trained via Reinforcement Learning, a machine learning approach. Optimization points are subsequently derived and fed back into the hardware development. With this Concurrent Engineering strategy a fast development of this robotic hand is possible. The paper outlines the relevant key strategies and gives insight into the design process. At the end, the final hand with its capabilities is presented and discussed.

Learning via human feedback in continuous state and action spaces

Abstract: This paper considers the problem of extending Training an Agent Manually via Evaluative Reinforcement (TAMER) in continuous state and action spaces. Investigative research using the TAMER framework enables a non-technical human to train an agent through a natural form of human feedback (negative or positive). The advantages of TAMER have been shown on tasks of training agents by only human feedback or combining human feedback with environment rewards. However, these methods are originally designed for discrete state-action, or continuous state-discrete action problems. This paper proposes an extension of TAMER to allow both continuous states and actions, called ACTAMER. The new framework utilizes any general function approximation of a human trainer's feedback signal. Moreover, a combined capability of ACTAMER and reinforcement learning is also investigated and evaluated. The combination of human feedback and reinforcement learning is studied in both settings: sequential and simultaneous. Our experimental results demonstrate the proposed method successfully allowing a human to train an agent in two continuous state-action domains: Mountain Car and Cart-pole (balancing).

A framework for the intelligent delivery and user-adequate visualization of process information

Abstract: A continuously increasing amount of data makes it difficult for knowledge-workers to identify the information they need to perform their tasks in the best possible way. Particularly challenging in this context is the alignment of process-related information (e.g., working instructions, best practices) with business processes. In fact, process-related information (process information for short) and business processes are usually handled separately. On one hand, shared drives, databases, and information systems are used to manage process information, on the other, process management technology provides the basis for managing business processes. In practice, enterprises often establish (Intranet) portals to connect both perspectives. However, such portals are not sufficient. Reasons are that process information is usually delivered without considering the current work context and business processes are presented to process participants in a rather static manner. Therefore, enterprises crave for new ways of making process information available. This paper picks up this challenge and presents the niPRO framework. niPRO is based on semantic technology and enables the intelligent delivery and user-adequate visualization of comprehensive process information.

Monte-Carlo tree search for Bayesian reinforcement learning

Abstract: Bayesian model-based reinforcement learning can be formulated as a partially observable Markov decision process (POMDP) to provide a principled framework for optimally balancing exploitation and exploration. Then, a POMDP solver can be used to solve the problem. If the prior distribution over the environment's dynamics is a product of Dirichlet distributions, the POMDP's optimal value function can be represented using a set of multivariate polynomials. Unfortunately, the size of the polynomials grows exponentially with the problem horizon. In this paper, we examine the use of an online Monte-Carlo tree search (MCTS) algorithm for large POMDPs, to solve the Bayesian reinforcement learning problem online. We will show that such an algorithm successfully searches for a near-optimal policy. In addition, we examine the use of a parameter tying method to keep the model search space small, and propose the use of nested mixture of tied models to increase robustness of the method when our prior information does not allow us to specify the structure of tied models exactly. Experiments show that the proposed methods substantially improve scalability of current Bayesian reinforcement learning methods.

Mixed electrolytes in hydrophobic interaction chromatography.

Abstract: An essential part of the modulation of protein-binding capacity in hydrophobic interaction chromatography is the buffer-salt system. Besides using "single" electrolytes, multicomponent electrolyte mixtures may be used as an additional tool. Both the protein solubility and the binding capacity depend on the position of a salt in the so-called Hofmeister series. Specific interactions are observed for an individual protein-salt combination. For salt mixtures, selectivity, recovery, and binding capacity do not behave like for the single salts that are positioned in between the two mixed components in the Hofmeister series, as the continuous correlation would suggest. Thus, finding strategies for mixed salts could potentially lead to improved capacities in hydrophobic interaction chromatography. Mixtures of ammonium sulfate, sodium citrate, sodium sulfate, sodium chloride, sodium acetate, and glycine were used to investigate the binding capacities for lysozyme and a monoclonal antibody on various hydrophobic resins. Resin capacity for two investigated proteins increases when mixtures consisting of a chaotropic and a kosmotropic salt are applied. It seems to be related to the rather basic isoelectric points of the proteins.

A multi-agent reinforcement learning approach for the efficient control of mobile robot

Abstract: This paper presents an application of the multi-agent reinforcement learning approach for the efficient control of a mobile robot. This approach is based on a multi-agent system applied to multi-wheel control. The robot's platform is decomposed into driving modules agents that are trained independently. The proposed approach incorporates multiple Q-learning agents, which permits them to effectively control every wheel relative to other wheels. The power reward policy with common error reward is adjusted to produce efficient control. The proposed approach is applied for the distributed control of a multi-wheel platform, in order to provide energy consumption optimization.

Measurement of the Internal Orbital Alignment of Oligothiophene-TiO2 Nanoparticle Hybrids

Abstract: X-ray photoemission spectroscopy (XPS), ultraviolet photoemission spectroscopy (UPS), and ultraviolet–visible spectroscopy (UV–vis) were used to investigate the electronic structure of the inner-molecule interface in oligothiophene-TiO2 organic molecule/nanoparticle hybrids. In these molecular structures the TiO2 nanoparticles were covalently bonded to the oligothiophene ligands. The discussed experiments utilized electrospray in-vacuum deposition, enabling the in situ characterization of these materials without the presence of significant ambient contamination. A comparison between the electronic structures of the individual molecular components of the hybrid with the assembled material enabled the determination of the orbital line-up at the internal interface of the hybrid molecules. Transmission electron microscopy (TEM) was used to investigate the morphology and size distribution of the nanoparticles. The results showed that the covalent bond causes an interface dipole at the junction between organic ...

Optimization of a pump health monitoring system using fuzzy logic

Abstract: Condition-monitoring plays an increasingly important role for technical processes in order to improve reliability, availability, maintenance and lifetime. As a consequence of increasing demands for product quality and efficiency as well as increased integration of control systems in costly and safety-critical mechatronic processes, the field of health monitoring is gaining interest. This paper is based on a current research project and describes the application of fuzzy-logic for the generation of health status information for pump systems. The unique quality of the presented approach is the collection of degradation information in form of a failure mode and effects analysis elaborated together with pump experts. This analysis resulted in multiple degradation indicators which are then used in a fuzzy system in order to generate health status information. This information is then concentrated by means of an algorithm which also uses an analogy to the failure modes and effects analysis. The result is a single number indicate the current health of a pump system.

Coaching performance and leadership behaviours in team sports

Abstract: The aim of this study was to investigate coaching performance in team sports taking leadership behaviours into focus. To do so, coaching performance was put in a literature-based frame and analysed with reference to a task structure based on the idea of hierarchical planning. The focus of the paper is on a mixed methods multi-strand study using qualitative as well as quantitative threads to develop and verify a set of coaching strategies focussing on teambuilding and team leadership. Qualitative analyses showed that coaches do have a clear understanding of forming and leading a team, which could be shown by a specific set of strategies being used by high performance coaches from different team sports (basketball, football, handball, and volleyball). These strategies could be confirmed in a sequential quantitative study analysing coaches’ and players’ attitudes towards the previously analysed schemes. The results of this study are discussed in terms of methodical and practical implications.

LED color mixing with diffractive structures

Abstract: Lighting solutions with colored LEDs provide many opportunities for illumination. One of these opportunities is to create a color tunable light source. In this way different kinds of white light (color temperature) as well as discrete colors may be realized. This opens the field for applications as mood lighting. But there is always a spatial separation of the distinct LEDs that might get converted into an angular separation by any collimating optics. This angular separation causes such problems like color fringes and colored shadows that cannot be accepted in most applications. Conventional methods to solve these problems include e.g. mixing rods or dichroic filters. A new approach is the use of the dispersive effect of a diffractive structure to compensate the angular separation of the different colors. In this contribution the potential and limitations of diffractive structures in LED color mixing applications are discussed. Ray tracing simulations were performed to analyze such important parameters like efficiency, color performance and the cross section of the color mixing optics. New means for the estimation of color mixing performance were developed. A software tool makes it possible to detect the color distribution within ray trace data and it provides a quality factor to estimate the color mixing performance. It can be shown that the spectral band width has a large influence on the mixing process. Ray tracing simulations are compared with results of an experimental setup such that both measured as well as simulated data is presented.

Mann und Rang – die Rolle von Konkurrenz für die Männergesundheit

Abstract: Zwischen sozialer und gesundheitlicher Lage besteht ein robuster, kontinuierlicher und teilweise deutlich geschlechtsabhangiger Zusammenhang: Manner reagieren auf ihren soziookonomischen Status etwa bezuglich der Mortalitat sensibler als Frauen. Ein Geschlechtsunterschied zeigt sich v. a. fur Erkrankungen, fur die auch – zu einem erheblichen Teil durch die subjektive soziale Lage vermittelter – psychosozialer Stress einen Risikofaktor darstellt. Soziallagebedingte psychosoziale Belastungen scheinen somit fur Manner gesundheitlich noch bedeutsamer zu sein als fur Frauen. Neurophysiologisch hat v. a. die chronische Uberaktivierung der HPA-Achse zentrale Bedeutung fur die soziallagebedingte Stressbelastung. Die starkste HPA-Aktivitat wird durch soziale Situationen ausgelost, die durch Konkurrenz gepragt sind. Manner zeigen im Vergleich zu Frauen einerseits eine starkere Konkurrenzbereitschaft, andererseits eine starkere Stressantwort auf sozial-evaluative Situa­tionen. HPA-Stress wird mit verschiedensten Volkskrankheiten sowie ganz konkret mit depressiven Storungen in Verbindung gebracht. Ein hoher Grad an Konkurrenz und hierarchisch gepragtem Selbstverstandnis wird entsprechend als wesentlicher gesellschaftlicher Risikofaktor betrachtet. Bisher ist menschliches Rangverhalten jedoch vergleichsweise wenig erforscht und konkurrenzspezifische gesundheitsbezogene Ansatze sind rar. Ein aktuell breit diskutierter Handlungsansatz, den Grad an Konkurrenz zu beeinflussen, ist der Fokus auf gesellschaftlichen Egalitarismus. Differenziertere Ansatze konnten sich auf kulturell etablierte konkurrenzmindernde Strategien stutzen, etwa Demut induzierende Ansatze. Methodisch vielversprechend ware insbesondere der Setting-Ansatz, in dessen Rahmen Konkurrenz als Zielgrose der Pravention und Gesundheitsforderung spezifisches Gewicht in pragenden Lebenswelten verliehen werden konnte. Zu beachten ware dabei der Zielkonflikt zwischen wettbewerblicher Konkurrenz als gesundheitlicher Determinante und der Bewertung von Wettbewerbsfahigkeit als gesellschaftlichem Fortschritts- und Wachstumsmotor.

Stressbewältigung und Gesundheit: kulturvergleichende und interkulturelle Aspekte

Abstract: Stress und Gesundheitsverhalten sind zentrale Themen kulturvergleichender Arbeiten der Psychologie (zusammmenfassend Kitayama & Cohen, 2007). Die gesundheitspsychologische Migrationsforschung widmet sich insbesondere praventivem Gesundheitsverhalten (z. B. Teilnahme an Vorsorgeuntersuchungen, Nutzung von Gesundheitsinformationen, Drogenvermeidung, Schutzverhalten, Ernahrungs- und Bewegungsgewohnheiten), Stress- und Krankheitsbewaltigung, Barrieren im Aufsuchen medizinischer Hilfe sowie generellen Gesundheitsrisiken (vgl. Kim, Wong & Maffini, 2010; Kizilhan & Bermejo, 2009; Schulz, 2002; Schulz & Gutierrez-Dona, 2002).

Measuring Professional Competence

Abstract: The PISA consortium with its research design and methodology has set new standards for educational research and fundamentally changed the cooperation between VET research and VET policy. This is mainly due to the fact that policy makers and the scientific community alike accepted the PISA methodology almost without any reservation. This is a new situation, which since then poses a challenge for VET researchers to extend competence diagnostics to ever wider fields of application. It was thus no surprise when already in 2003 the idea of a VET PISA was proposed for the first time, to be followed in Germany shortly afterwards by a feasibility study commissioned by the Federal Ministry of Economics on an international VET PISA (cf. Baethge et al. 2006).

Foundations of a Competence Model

Abstract: The impact of vocational education on competence development cannot be estimated as long as the desired outcomes of programmes and institutions of vocational education have not been spelled out. After all, vocational training processes are based on the intention to influence the process of learning action-guiding rules that are valid not by virtue of natural or technological “regularities”, but by virtue of social convention. A model of professional competence development therefore always includes a normative component (Brandstadter 1984). Accordingly we first have to discuss some aspects of the normative and curricular foundations of vocational education. The framework of vocational education can be based on the following four components:

Agentenbasierte Koordination und Überwachung des Designs mechatronischer Systeme

Abstract: Der Entwicklungsprozess mechatronischer Produkte ist gepragt durch deren interdisziplinaren Charakter und steigende Komplexitat Es gilt, diese Komplexitat durch methodische Ansatze beherrschbar zu machen und, unter Berucksichtigung gegenseitiger Abhangigkeiten, die beteiligten Entwickler effizient zu koordinieren Modellbasierte Ansatze zur Modellierung von System und Entwicklungsaktivitaten haben bereits erste Moglichkeiten hervorgebracht, den Entwicklungsprozess in diesem Sinne zu unterstutzen Dieser Beitrag stellt einen agentenbasierten Ansatz zur IT-unterstutzten Koordination und Uberwachung des Designs mecha-tronischer Produkte vor Dabei werden Resultate modellbasierter Ansatze als Wissensbasen verwendet, um Informationen uber System und Prozess zu erhalten und gegenseitige Abhangigkeiten zu uberwachen Der Beitrag stellt das Konzept sowie die Agentenarchitektur vor und zeigt dessen Anwendbarkeit anhand eines Anwendungsbeispiels

The COMET Rating Procedure in Practice: Some Conclusions

Abstract: The quality of a measurement tool for the evaluation of professional competence and competence development depends largely on the question to what extent the ratings of the individual solutions of the participants by the evaluators (raters) converge or diverge (interrater reliability).

Maschinelles Lernen und Data Mining

Abstract: Definiert man den Begriff der KI wie im Buch von Elaine Rich [Ric83] ″ Artificial Intelligence is the study of how to make computers do things at which, at the moment, people are better.″ und bedenkt, dass die Computer uns Menschen insbesondere bezuglich der Lernfahigkeit weit unterlegen sind, dann folgt daraus, dass die Erforschung der Mechanismen des Lernens und die Entwicklung maschineller Lernverfahren eines der wichtigsten Teilgebiete der KI darstellt.

Kleine Kinder spielen und lernen mit bunten Perlen

Abstract: Kurzfassung:Im nachfolgenden Artikel wird eine Thematik aufgegriffen, an der Silvia Wessolowski und ich seit 2005 gemeinsam gearbeitet haben: die fruhe mathematische Bildung. Herausgefordert von der Forderung nach domanenspezifischen Bildungsangeboten in der Kita, setzten wir uns mit der Frage auseinander, wie mathematische Lernprozesse in der Kita angeregt werden konnen. Wir verfolgten einen Ansatz der integrativen mathematischen Bildung in der Kita und diskutierten viel uber den Einsatz von Alltags-Materialen fur mathematische Lernprozesse. Im Artikel werden unsere damals entstandenen Ideen am Alltags-Material „Perlen“ weiterentwickelt und konkretisiert. Im ersten Teil des Beitrags wird erortert, welche Moglichkeiten das Material „bunte Perlen“ fur mathematische Lernprozesse impliziert. Der theoretischen Analyse schliest sich die Darstellung der Beobachtungen aus einer praktischen Erprobung an, die in drei verschiedenen Kitas mit je sechs Kindern im Alter von funf bis sechs Jahren stattgefunden hat.

The COMET Competence Model: Foundations for the Study of Professional Competence and Identity

Abstract: The relevance of competence diagnostics on the basis of theoretical models has been emphasized in the debates in educational science at least since the PISA project (Klieme and Leutner 2006). There were already models for a systematic description of competence in the natural sciences (especially Bybee 1997), which inspired the modeling in the PISA project and the learning and teaching research in the field of science education (cf. Schecker and Parchmann 2006, 45; Baumert et al. 2001).

Data Format for Ray File Standard

Abstract: A working group for the Illuminating Engineering Society (IES) recently published the TM-25 standard file format for disseminating source ray data. This presentation will inform the community of the results.

Test Development and Design of the Study

Abstract: The test assignments are the core of the surveys in the COMET project; they are the result of the technical, didactical, and psychometrical preparation of the large-scale measurement. In order to guarantee the objectivity of the test, measures were taken to make sure that none of the test assignments would become known in advance. For instance, all people involved in the COMET project committed themselves to treat the assignments confidentially.

Results of the Main Phase

Abstract: The research and development tasks of the COMET project in 2009 were extended on the basis of the results from 2008 by the inclusion of students from three technical colleges (Fachschulen) and the establishment of a cooperation with China involving 800 trainees and students from technical colleges in the Beijing region

Grenzen der Logik

Abstract: Wie schon an verschiedenen Stellen erwahnt, gibt es auf der Suche nach einem Beweis fast immer in jedem Schritt viele (je nach Kalkul eventuell sogar unendlich viele) Moglichkeiten fur die Anwendung von Inferenzregeln. Es ergibt sich dadurch das schon erwahnte explosionsartige Wachsen des Suchraums (Abb. 4.1). In Worst-Case mussen zum Finden eines Beweises alle diese Moglichkeiten versucht werden, was in fur Menschen zumutbaren Zeitraumen aber meist nicht moglich ist.

Einstellungen von Grundschulkindern zu Nahrungsmitteln

Abstract: In der Studie wurde untersucht, ob Geschmackspraferenzen fur gesunde und ungesunde Nahrungsmittel sowie implizite Einstellungen zu Nahrungsmitteln bei Kindern im Grundschulalter Zusammenhange mit dem Body Mass Index (BMI-SDS) aufweisen. 148 Kinder der dritten Klasse im Alter zwischen 7 und 10 Jahren nahmen an der Studie teil. Die Geschmackspraferenzen wurden mit Ratingskalen im Selbstbericht erfasst, die impliziten Einstellungen mit einem idiografischen Impliziten Assoziationstest (IAT). Im IAT wurden alle Stimuli der Konzepte (ich versus andere, gesunde Nahrungsmittel versus ungesunde Nahrungsmittel) mit Fotografien prasentiert. Die Ergebnisse zeigten, dass der IAT-Index zur Pradiktion des BMI einen signifikanten Beitrag leistet. Kinder, bei denen die Konzepte ich und ungesunde Nahrungsmittel starker assoziiert waren, wiesen auch einen hoheren BMI-SDS auf. Hingegen leisteten die expliziten Mase keinen signifikanten Beitrag zur Vorhersage des BMI. Die Befunde werden im Kontext des noch inkonsistenten Fors...

Logikprogrammierung mit Prolog

Abstract: Im Vergleich zu klassischen Programmiersprachen wie zum Beispiel C oder Pascal bietet die Logik die Moglichkeit, Zusammenhange elegant, kompakt und deklarativ zu beschreiben. Automatische Theorembeweiser sind sogar in der Lage, zu entscheiden, ob eine Anfrage logisch aus einer Wissensbasis folgt. Hierbei sind der Beweiskalkul und das in der Wissensbasis gespeicherte Wissen streng getrennt. Eine in Klauselnormalform aufgeschriebene Formel kann als Eingabe fur jeden Theorembeweiser verwendet werden, unabhangig vom verwendeten Beweiskalkul. Fur die Reprasentation von Wissen und das Schliesen ist dies von grosem Nutzen.

Prädikatenlogik erster Stufe

Abstract: Viele praktisch relevante Problemstellungen lassen sich mit der Sprache der Aussagenlogik nicht oder nur sehr umstandlich formulieren, wie man an folgenden Beispielen gut erkennt.

Suchen, Spielen und Probleme lösen

Abstract: Bei fast allen Inferenzsystemen stellt die Suche nach einer Losung, bedingt durch die extrem grosen Suchbaume, ein Problem dar. Aus dem Startzustand gibt es fur den ersten Inferenzschritt viele Moglichkeiten. Fur jede dieser Moglichkeiten gibt es im nachsten Schritt wieder viele Moglichkeiten und so weiter.

Results 2008: Apprentices Competence

Abstract: Not all at-risk students become at-risk trainees Vocational education appears to have some potential for compensation More than one third of the students at risk turn out to be trainable, if only at a low competence level

Method for producing very long pipe or profile element for bioreactors for producing photo-chromic organisms and cell cultures, involves leaving end of tensile force acts by extruder to pulls beginning of element from extruder

Abstract: The method involves preparing the profile elements (1) in the immediate vicinity of installation site. The end of a tensile force acts is leaved by the extruder (2) to pulls the beginning (5) of the element from the extruder during the manufacture of the profile element outside of the extruder. The production of the profile elements used in the composition for extrusion of thermoplastic such as polymethyl methacrylate, polycarbonate, polyethylene, polyethylene terephthalate or PVC is formed.