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The overall goal of this work is to detect and analyze a person's movement, breathing and heart rate during sleep in a common bed overnight without any additional physical contact. The measurement is performed with the help of
sensors placed between the mattress and the frame. A two-stage pattern classification algorithm based has been implemented that applies statistics analysis to recognize the position of patients. The system is implemented in a sensors-network, hosting several nodes and communication end-points to support quick and efficient classification. The overall tests show convincing results for the position recognition and a reasonable overlap in matching.
We consider the problem of increasing the informative value of electrocardiographic (ECG) surveys using data from multichannel electrocardiographic leads, that include both recorded electrocardiosignals and the coordinates of the electrodes placed on the surface of the human torso. In this area, we were interested in reconstruction of the surface distribution of the equivalent sources during the cardiac cycle at relatively low hardware cost. In our work, we propose to reconstruct the equivalent electrical sources by numerical methods, based on integral connection between the density of electrical sources and potential in a conductive medium. We consider maps of distributions of equivalent electric sources on the heart surface (HSSM), presenting source distributions in the form of a simple or double electrical layer. We indicate the dynamics of the heart electrical activity by the space-time mapping of equivalent electrical sources in HSSM.
Sleep study can be used for detection of sleep quality and in general bed behaviors. These results can helpful for regulating sleep and recognizing different sleeping disorders of human. In comparison to the leading standard measuring system, which is Polysomnography (PSG), the system proposed in this work is a non-invasive sleep monitoring device. For continuous analysis or home use, the PSG or wearable Actigraphy devices tends to be uncomfortable. Besides, these methods not only decrease practicality due to the process of having to put them on, but they are also very expensive. The system proposed in this paper classifies respiration and body movement with only one type of sensor and also in a noninvasive way. The sensor used is a pressure sensor. This sensor is low cost and can be used for commercial proposes. The system was tested by carrying out an experiment that recorded the sleep process of a subject. These recordings showed excellent results in the classification of breathing rate and body movements.
Investigation of magnetic effects on austenitic stainless steels after low temperature carburization
(2018)
In Anlehnung an das Tempcore-Verfahren wurde an wärmebehandeltem Stabstahl das Zugverfestigungsverhalten des Kernes, der Außenhaut sowie dem gesamten Stab experimentell und numerisch ermittelt. Es zeigte sich, dass die Dehnungen am Kern und am äußeren Rand gleich sind und der Einfluss des Kerngefüges entscheidend für den Beginn der Einschnürung in der Außenhaut ist. Eine Verbesserung der Eigenschaften des Kerngefüges kann somit die Bruchempfindlichkeit des gesamten Stabes reduzieren.
Although the Hospice Foundation in Constance knew they had a personnel
problem, they were unsure how to begin to fix it. In addition to difficulties in
finding and keeping employees, the Hospice Foundation’s employees were
often on sick leave, adding pressure on remaining staff. Twelve communication
design students in the masters program at the University of Applied
Sciences in Constance (HTWG Konstanz) conducted a study aimed at
identifying the causes for these problems and, more generally, understanding
how the employees work and feel. Even though the methods in this
study are well known, it presents an important prototype for designers and
design researchers because of its success in finding useful insights. It also
serves as a pre-design project briefing for both management and designers.
It demonstrates the usefulness of qualitative methods in providing a deeper
understanding of a complex situation and its usefulness as a strategic tool
and for defining a project’s focus and scope. Ideally, it also provides insights
into health care for the elderly.
Ingenieure auf die Bühne
(2018)
The article opens with brief examples of the varied contexts in which professionals with expert knowledge of intercultural communication are commissioned
by organisations to help improve organisational and individual performance.
The development needs that are evident in these contexts entail a broader repertoire of competencies than those generally reflected in the term intercultural communication skills, and so the next section elaborates on the concept of intercultural interaction competence (ICIC), reporting on the numerous sub-competencies which go to make up the ability to perform joint and purposeful activity effectively and appropriately across cultures.
The third section reports on approaches to developing the ICIC of members of organisations, discussing desirable framework conditions for the development
intervention, its possible goals, the nature of the cognitive, affective and behavioural development outcomes which can be achieved, and the content, methods and tools available to the intercultural developer.
The article finishes with a brief consideration of the qualification profile of interculturalists engaged in this kind of work, pointing out that a multi-disciplinary background will enable interculturalists to meet a broad range of organisational and human resource development needs in the area of intercultural communication which go beyond the ‘mere’ development of communicative foreign-language skills.
Einfluss der Oberfläche
(2018)
Long-term sleep monitoring can be done primarily in the home environment. Good patient acceptance requires low user and installation barriers. The selection of parameters in this approach is significantly limited compared to a PSG session. The aim is a qualified selection of parameters, which on the one hand allow a sufficiently good classification of sleep phases and on the other hand can be detected by non-invasive methods.
The process of restoring our body and brain from fatigue is directly depend-ing on the quality of sleep. It can be determined from the report of the sleep study results. Classification of sleep stages is the first step of this study and this includes the measurement of biovital data and its further processing.
In this work, the sleep analysis system is based on a hardware sensor net, namely a grid of 24 pressure sensors, supporting sleep phase recognition. In comparison to the leading standard, which is polysomnography, the proposed approach is a non-invasive system. It recognises respiration and body move-ment with only one type of low-cost pressure sensors forming a mesh archi-tecture. The nodes implement as a series of pressure sensors connected to a low-power and performant microcontroller. All nodes are connected via a system wide bus with address arbitration. The embedded processor is the mesh network endpoint that enables network configuration, storing and pre-processing of the data, external data access and visualization.
The system was tested by executing experiments recording the sleep of different healthy young subjects. The results obtained have indicated the po-tential to detect breathing rate and body movement. A major difference of this system in comparison to other approaches is the innovative way to place the sensors under the mattress. This characteristic facilitates the continuous using of the system without any influence on the common sleep process.
Viele Unternehmen befassen sich mit Compliance und Corporate Social Responsibility (CSR) getrennt voneinander. Dies mag zum einen der Historie der beiden Themen geschuldet sein, zum anderen aber auch der organisatorischen Verortung vonseiten insbesondere großer Unternehmen, die Compliance häufig der Rechtsabteilung und CSR der Kommunikationsabteilung zuordnen. Durch die isolierte Betrachtung der Themen bleiben aber nicht nur potenzielle Synergien ungenutzt, es werden auch unnötige Konflikte und Redundanzen erzeugt, die sich durch eine integrierte Herangehensweise vermeiden ließen. Bezogen auf die Umsetzung wird ein integriertes Vorgehen durch eine Reihe von Instrumenten begünstigt, die per se sowohl CSR- als auch compliancerelevante Themen ansprechen. Dass eine, aus theoretischer Sicht notwendige und sinnvolle Verknüpfung der beiden Themen auch in der Praxis künftig an Bedeutung gewinnen wird, lässt sich bereits heute an den letzten Überarbeitungen der fünf „großen“ internationalen CSR-Standards bzw. Rahmenwerken erkennen, die allesamt Themen ansprechen, die klassischerweise sowohl dem CSR- als auch dem Compliancemanagement zugeordnet werden können.
CSR und Compliance
(2018)
Viele Unternehmen befassen sich mit den Themen CSR und Compliance – in erster Linie aufgrund ihrer historischen Entwicklung – im Rahmen paralleler organisationaler Strukturen. Da CSR und Compliance nach heutigem Verständnis jedoch sowohl in der Theorie als auch in der Praxis inhaltlich zunehmend große Schnittmengen aufweisen bzw. einander wechselseitig bedingen, kann dies zu unnötigen Redundanzen und Zielkonflikten in der Umsetzung führen.
Das vorliegende Herausgeberwerk knüpft an dieser Stelle an und zeigt auf, was CSR und Compliance gemein ist, inwiefern sie einander bedingen und folglich synergetisch gemanagt werden können oder sogar sollten. Neben Wissenschaftlern sollen dazu auch explizit Praktiker zu Wort kommen, die mit der Integration von CSR- und/oder Compliancethemen betraut sind und Hinweise zu deren praktischer Umsetzung geben können.
Mit dem vorliegenden Sammelband werden daher nicht nur Wissenschaftler, sondern ausdrücklich auch Anwender angesprochen, die Denkanstöße oder konkrete Hinweise zur ganzheitlichen Integration und Umsetzung der beiden Themen aus der Lektüre mitnehmen möchten.
Schreiben und Rhetorik an einer Hochschule für angewandte Wissenschaften - ein Erfahrungsbericht
(2018)
Traggerüste
(2018)
Stolperstein Mathematik
(2018)
The paper investigates an innovative actuator combination based on the magnetic shape memory technology. The actuator is composed of an electromagnet, which is activated to produce motion, and a magnetic shape memory element, which is used passively to yield multistability, i.e. the possibility of holding a position without input power. Based on the experimental open-loop frequency characterization of the actuator, a position controller is developed and tested in several experiments.
Was in Kommunen im benachbarten Ausland, bspw. der Schweiz, Oesterreich oder den Niederlanden, offenbar seit vielen Jahren Stand der Technik ist, ist auf Deutschlands Kommunalstrassen eine 'Sonderbauweise': Verkehrsflaechen aus Beton. Die Gruende fuer die Vernachlaessigung der Betonbauweise im kommunalen Umfeld liegen offenbar in einer aufwendigeren Planung, hoeheren Ausfuehrungskosten, einem komplexeren Einbau (gerade in Zusammenhang mit Einbauten), Instandhaltungsmassnahmen und Massnahmen Dritter an den Ver- und Entsorgungseinrichtungen. Offen ist auch die Frage, inwieweit sich die hoeheren Aufwendungen bei der Betonbauweise hinsichtlich Planung und Ausfuehrung im Rahmen einer Lebenszyklusbetrachtung im Vergleich zur Asphaltbauweise durch einen geringeren Erhaltungsbedarf amortisieren oder ggf. sogar guenstiger darstellen. Infolge vermehrt auftretender typischer Schaeden wie Spurrinnen und Verdrueckungen werden hochbelastete kommunale Verkehrsflaechen wie Bushaltestellen, Busspuren und Kreisverkehre immer haeufiger anstatt in Asphalt oder Pflaster in Beton ausgefuehrt. Die Thematik 'Einsatz von Betonflaechen in Kommunen' ist sehr umfangreich und weitlaeufig. Generell wird hier auch auf die spezifischen Merkblaetter der FGSV verwiesen. Mit den Ausfuehrungen im Fachbeitrag soll demnach grundsaetzlich auf die Belange der Planung, des Baus und die Wirtschaftlichkeit kommunaler Verkehrsflaechen in Betonbauweise eingegangen werden. Es koennen leider nicht alle Besonderheiten und Einzelheiten wie bspw. Baustoffe (Glasfaser) Beruecksichtigung finden. Ziel ist, generelle Moeglichkeiten hinsichtlich des Einsatzes von Betonflaechen im kommunalen Bereich aufzuzeigen. Besonderer Dank gilt dem Strassenbauamt Boeblingen sowie Herrn Baudirektor Andreas Klein, dessen persoenliche Erfahrungen hier einfliessen durften.
We propose a novel end-to-end neural network architecture that, once trained, directly outputs a probabilistic clustering of a batch of input examples in one pass. It estimates a distribution over the number of clusters k, and for each 1≤k≤kmax, a distribution over the individual cluster assignment for each data point. The network is trained in advance in a supervised fashion on separate data to learn grouping by any perceptual similarity criterion based on pairwise labels (same/different group). It can then be applied to different data containing different groups. We demonstrate promising performance on high-dimensional data like images (COIL-100) and speech (TIMIT). We call this “learning to cluster” and show its conceptual difference to deep metric learning, semi-supervise clustering and other related approaches while having the advantage of performing learnable clustering fully end-to-end.
Formgedächtnislegierungen
(2018)
Formgedächtnislegierungen sind »Legierungen, die nach geeigneter Behandlung aufgrund einer martensitischen Umwandlung ihre Gestalt in Abhängigkeit von der Temperatur ändern«. Derartige Materialien werden in den nächsten Jahrzehnten eine wachsende Rolle in der Technik spielen. Um die Eigenschaften dieser Werkstoffe optimal nutzen zu können, ist es wichtig, den Einfluss des Herstellungs- und Verarbeitungsprozesses auf ihre Anwendung zu kennen.
Das Buch behandelt die metallkundlichen Hintergründe und die Verwendungsmöglichkeiten der Formgedächtnislegierungen in verständlicher, auf den Anwender zugeschnittener Weise.
Business units are increasingly able to fuel the transformation that digitalization demands of organizations. Thereby, they implement Shadow IT (SIT) to create flexible and innovative solutions. However, the individual implementation of SIT leads to high complexities and redundancies. Integration suggests itself to meet these challenges but can also eliminate the described benefits. In this emergent research, we develop propositions for a conceptual decision framework, that balances the benefits and drawbacks of an integration of SIT using a literature review as well as a multiple-case study. We thereby integrate the perspective of the overall organization as well as the specific business unit. We then pose six propositions regarding SIT integration that will serve to evaluate our conceptual framework in future research.
According to the World Food Organization, nearly half of all root and tuber crops worldwide are not consumed, but are lost due to inappropriate storage and post-harvest losses. In developing countries such as Ethiopia, potatoes have not been dried, but are traditionally stored in potato clamps. So far, dried potatoes have not been converted into usable foods.
The aim of the present work is to convert potatoes - perishable rootlets and tubers - into stable products by hot air drying. Hot air dryers are economical to operate in industrialized countries. In Africa, this is reserved for larger industrial companies only. In regions with a tropical climate, however, the use of solar tunnel dryers is worthwhile. These are a good choice for farming and small industries and wherever electrical energy is difficult or impossible to obtain.
In a first part of the work, the drying process of potatoes was investigated, in particular with regard to the change of thermal, mechanical and chemical quality parameters. In an evaluation of the literature it was found that potatoes are not subject to quality changes if the water activityis below a value of 0.2. In order to determine the water content associated with this value at storage temperature, the known equations for the sorption equilibrium were evaluated and verified with own experimental investigations. This determined the end point of the drying process.
The following experimental investigations showed a process-dependent change of the quality criteria such as color, shrinkage, and mechanical properties as well as the content of valuedetermining substances such as vitamin C and starch. The differences in the course and magnitude of the quality changes were attributed to the glass transition that takes place during the drying process. For the determination of the glass transition temperature a new, simple method based on the measurement of mechanical properties could be developed. The knowledge of the glass transition temperature allowed optimizing the drying process. The drying process could be carried out in the rubbery or glassy region, depending on the expected quality changes. Thus, all information was available to produce high quality dried potatoes in an industrial process.
Since the production of potato products in less industrialized regions without sufficient supply of electrical energy should be included, potatoes were dried with a solar tunnel dryer. Examination of the quality properties mentioned above confirmed the process-dependent quality changes.
Finally, the dried product was ground and with the flour thus produced, wheat flour was replaced for baking bread. An evaluation of the finished bread by a panel showed that the acceptance of the bread according to the new recipe was high, also with regard to baking volume, taste, texture and color.
This work shows that by drying potatoes can be transformed a well accepted, storable and easily transportable product. The risk of losses or degradation is minimized. It can be produced on an industrial as well as on farm level. If the influence of the glass transition is taken into account, it is possible to optimize the quality of the product.
Der Trend zu leichteren Konstruktionen und größeren Spannweiten macht es notwendig, den dynamischen Charakter der Einwirkungen auf die Tragsicherheit und Gebrauchstauglichkeit der Bauwerke stärker als bisher zu berücksichtigen; neben aerodynamischen und seismischen Einflüssen sind es solche aus Maschinenanlagen, aus dem Straßen- und Eisenbahnverkehr sowie von Menschen induzierte Einwirkungen, und nicht zuletzt Katastrophenlastfälle, wie Anprall, Flugzeugabsturz und anderes.
Ausgehend von den Grundlagen der Dynamik werden Berechnungs- und Bewertungsverfahren unterschiedlicher Strenge dargestellt und anhand zahlreicher Beispiele praxisbezogen erläutert. Die mathematischen Verfahren werden in einem ausführlichen Anhang dargelegt, die einzelnen Kapitel sind jeweils durch umfangreiche Hinweise auf die Fachliteratur ergänzt.
„Nackte Tatsachen genügen nicht, um den Leser bis zum Schluss bei der Stange zu halten. [Auch der] Verfasser von [Fach- und] Sachtexten hat das Recht – wenn nicht gar die Pflicht –, die Wunder der Erzählkunst für sich zu erschließen, um seine Texte zu einer interessanten und vergnüglichen Lektüre zu machen.“ – Der Vortrag geht der Frage nach, ob diese Forderung des vielgelesenen Ratgeberautors Sol Stein berechtigt ist und inwiefern sie eingelöst werden kann. Zu diesem Zweck werden Stil- und Kompositionsmittel aus den Bereichen Lexik, Grammatik, Syntax, Stilistik, Erzählstrategie und Textorganisation anhand von Formulierungsbeispielen vorgestellt und auf ihre Funktion in Erzählliteratur oder Journalismus hin untersucht. In einem zweiten Schritt wird jeweils nach der Übertragbarkeit dieser sprachlichen Mittel auf Fachtexte gefragt. Anhand parallel ausgerichteter Beispiele wird eine mögliche verlagerte Funktion im Wissenschaftskontext skizziert. Der erhoffte Erkenntnisgewinn des Vortrags betrifft sowohl das Verfassen eigener Publikationen als auch die Vermittlung von Schreibfähigkeiten für künftige Fachautor*innen, weshalb die Formulierungsbeispiele verschiedensten, auch technischen und naturwissenschaftlichen Domänen entnommen sind.
(Literaturangabe: Stein, Sol: Über das Schreiben [1995], dt. Waltraud Götting, 10. Aufl., Zweitausendeins, Frankfurt a. M., 2006, zit. S. 49)
Der Einsatz von Plagiatssoftware sollte auf die Zielgruppe abgestimmt sein. Da die Beurteilung des digitalen Prüfberichts Expertenwissen voraussetzt, erscheint ein unbegleiteter Zugriff nicht sinnvoll. Da meist nicht mit Betrugsabsicht, sondern aus Regelunkenntnis plagiiert wird, ist eine Beschränkung auf eine flächendeckende Detektion keine Lösung. Umfassendes Regelwissen, ein Verständnis für die grundlegende Bedeutung intertextueller Bezüge sowie selbstverantwortliches Handeln sind Vermittlungsziele der HTWG-Schreibberatung. Zu diesem Zweck macht das HTWG-Modell den Schreibkursbesuch zur Zulassungsvoraussetzung für die freiwillige Plagiatskontrolle und behält sich die Deutungshoheit über den Prüfbericht vor.
Smart-Future-Living-Bodensee
(2018)
Der Süden
(2018)
Dieser Beitrag untersucht, inwiefern die Sapir-Whorf-Hypothese, die die Abhängigkeit des Denkens von der Sprache postuliert, einen Erklärungsansatz zur raumsemantischen Konstruktion des touristischen Südens liefern kann. Sie dient als Analyseraster in Verbindung mit empirischen Befunden zu den touristischen Imageprofilen von Sevilla und Buenos Aires, die als Fallbeispiele touristischer Städte des Südens gewählt wurden.
Marketingrecht
(2018)
Dieses Buch legt eine umfassende Gesamtdarstellung des Marketingrechts vor und sensibilisiert für mögliche Rechtsprobleme im Marketing. Verantwortliche im Marketingmanagement, die Entscheidungen oft auch schnell treffen müssen, werden hier mit den Grundlagen rechtlicher Rahmenbedingungen vertraut gemacht. Der marketingspezifische Aufbau und die Entscheidungsorientierung gewährleisten dem Marketingmanagement als Hauptzielgruppe einen hohen Praxisnutzen. Der Leser erhält wertvolle Hinweise, wie er im Marketing effektiver und zielgerichteter mit der Rechtsabteilung oder externen Rechtsberatern kommunizieren kann.
Im Sinne einer dialogischen, transdisziplinären Auseinandersetzung zwischen künstlerischer Praxis, Kultur- und Ingenieurwissenschaften geht es bei diesem Projekt um die Entwicklung einer künstlerisch-wissenschaftlichen Fallstudie mit den Zielen der konkreten Erarbeitung eines Kunstwerks unter den Bedingungen digitaler Medien - und um eine Befragung dieser Medien aus der Perspektive der
künstlerischen Praxis, der Interfacegestaltung und der Entwurfswissenschaften (Teil der UDK Berlin).
Bericht aus dem Freistellungssemester Sommer 2018
When integrating task-based learning into LSP courses, assessment procedures have to reflect the communicative goals of such tasks. However, performances on authentic and complex tasks are often difficult to score, because they involve not only specific language ability but also field specific knowledge. Moreover, the emphasis of tasks on meaning suggests that the communicative outcome should be regarded as the main criterion of success. This paper focuses on task design and scoring. It is argued that tasks have to be adapted to assessment purposes. However, to avoid a misalignment between teaching/learning and assessment, they should comprise the main features of LSP tasks in the sense of task-based language learning.
Simon Grimm examines new multi-microphone signal processing strategies that aim to achieve noise reduction and dereverberation. Therefore, narrow-band signal enhancement approaches are combined with broad-band processing in terms of directivity based beamforming. Previously introduced formulations of the multichannel Wiener filter rely on the second order statistics of the speech and noise signals. The author analyses how additional knowledge about the location of a speaker as well as the microphone arrangement can be used to achieve further noise reduction and dereverberation.
Error correction coding based on soft-input decoding can significantly improve the reliability of non-volatile flash memories. This work proposes a soft-input decoder for generalized concatenated (GC) codes. GC codes are well suited for error correction in flash memories for high reliability data storage. We propose GC codes constructed from inner extended binary Bose-Chaudhuri-Hocquenghem (BCH) codes and outer Reed-Solomon codes. The extended BCH codes enable an efficient hard-input decoding. Furthermore, a low-complexity soft-input decoding method is proposed. This bit-flipping decoder uses a fixed number of test patterns and an algebraic decoder for soft-decoding. An acceptance criterion for the final candidate codeword is proposed. Combined with error and erasure decoding of the outer Reed-Solomon codes, this acceptance criterion can improve the decoding performance and reduce the decoding complexity. The presented simulation results show that the proposed bit-flipping decoder in combination with outer error and erasure decoding can outperform maximum likelihood decoding of the inner codes.
The introduction of multiple-level cell (MLC) and triple-level cell (TLC) technologies reduced the reliability of flash memories significantly compared with single-level cell flash. With MLC and TLC flash cells, the error probability varies for the different states. Hence, asymmetric models are required to characterize the flash channel, e.g., the binary asymmetric channel (BAC). This contribution presents a combined channel and source coding approach improving the reliability of MLC and TLC flash memories. With flash memories data compression has to be performed on block level considering short-data blocks. We present a coding scheme suitable for blocks of 1 kB of data. The objective of the data compression algorithm is to reduce the amount of user data such that the redundancy of the error correction coding can be increased in order to improve the reliability of the data storage system. Moreover, data compression can be utilized to exploit the asymmetry of the channel to reduce the error probability. With redundant data, the proposed combined coding scheme results in a significant improvement of the program/erase cycling endurance and the data retention time of flash memories.
Generalized concatenated (GC) codes with soft-input decoding were recently proposed for error correction in flash memories. This work proposes a soft-input decoder for GC codes that is based on a low-complexity bit-flipping procedure. This bit-flipping decoder uses a fixed number of test patterns and an algebraic decoder for soft-input decoding. An acceptance criterion for the final candidate codeword is proposed. Combined with error and erasure decoding of the outer Reed-Solomon codes, this bit-flipping decoder can improve the decoding performance and reduce the decoding complexity compared to the previously proposed sequential decoding. The bit-flipping decoder achieves a decoding performance similar to a maximum likelihood decoder for the inner codes.
This work proposes a construction for low-density parity-check (LDPC) codes over finite Gaussian integer fields. Furthermore, a new channel model for codes over Gaussian integers is introduced and its channel capacity is derived. This channel can be considered as a first order approximation of the additive white Gaussian noise channel with hard decision detection where only errors to nearest neighbors in the signal constellation are considered. For this channel, the proposed LDPC codes can be decoded with a simple non-probabilistic iterative decoding algorithm similar to Gallager's decoding algorithm A.
Objective: This paper presents an algorithm for non-invasive sleep stage identification using respiratory, heart rate and movement signals. The algorithm is part of a system suitable for long-term monitoring in a home environment, which should support experts analysing sleep. Approach: As there is a strong correlation between bio-vital signals and sleep stages, multinomial logistic regression was chosen for categorical distribution of sleep stages. Several derived parameters of three signals (respiratory, heart rate and movement) are input for the proposed method. Sleep recordings of five subjects were used for the training of a machine learning model and 30 overnight recordings collected from 30 individuals with about 27 000 epochs of 30 s intervals each were evaluated. Main results: The achieved rate of accuracy is 72% for Wake, NREM, REM (with Cohen's kappa value 0.67) and 58% for Wake, Light (N1 and N2), Deep (N3) and REM stages (Cohen's kappa is 0.50). Our approach has confirmed the potential of this method and disclosed several ways for its improvement. Significance: The results indicate that respiratory, heart rate and movement signals can be used for sleep studies with a reasonable level of accuracy. These inputs can be obtained in a non-invasive way applying it in a home environment. The proposed system introduces a convenient approach for a long-term monitoring system which could support sleep laboratories. The algorithm which was developed allows for an easy adjustment of input parameters that depend on available signals and for this reason could also be used with various hardware systems.
We identify 74 generic, reusable technical requirements based on the GDPR that can be applied to software products which process personal data. The requirements can be traced to corresponding articles and recitals of the GDPR and fulfill the key principles of lawfulness and transparency. Therefore, we present an approach to requirements engineering with regard to developing legally compliant software that satisfies the principles of privacy by design, privacy by default as well as security by design.
Allgemeine Geschäftsbedingungen als Instrument der Vereinfachung betrieblicher Vertragsgestaltung
(2018)
In einigen europäischen Nachbarländern herrschen weitaus schlechtere Voraussetzungen für die Binnen-schifffahrt als in Deutschland. Die wenigsten Länder verfügen über eine so effiziente Wasserstraße wie beispielsweise den Rhein. Dennoch forcieren nicht wenige die Verlagerung von Transporten von der Straße auf das Binnenschiff.
Infolge des Klimawandels sind entlang der Gewässer Baden-Württembergs verschärfte Niedrigwassersituationen zu erwarten, die unter Umständen zu Wassernutzungskonflikten der lokalen Akteure führen. Anhand des Kochers und der Murg wurden mit Hilfe einer Stakeholder-Analyse solche Konflikte identifiziert sowie erste Handlungsoptionen für eine Niedrigwasservorsorge bzw. ein Niedrigwassermanagement erarbeitet. Den Erhebungen zufolge treten Wassernutzungskonkurrenzen in fast allen Nutzergruppen auf, jedoch mit unterschiedlicher Ausprägung. Hierbei stehen bestimmte Sektoren teilweise mit mehreren Stakeholder-Gruppen im Widerstreit, andere Gruppen haben dagegen keine Erfahrung mit Konkurrenzsituationen. Weiterhin ist auffällig, dass Niedrigwasserereignisse an beiden Flüssen lediglich einen Teil der Nutzungskonflikte auslösen. Ein Großteil der Streitfragen wird durch anthropogene Einflüsse verursacht.
In tourism, energy demands are particularly high. Tourism facilities such as hotels require large amounts of electric and heating / cooling energy while their supply is usually still based on fossil energies.
This research approach analyses the potential of promoting renewable energies in tourism. It focuses on a combined and hence highly efficient production of both electric and thermal energy by biogas plants on the one hand and its provision to local tourism facilities via short distance networks on the other. Considering regional resource availability as well as socio-economic aspects, it thus examines strengths, weaknesses, opportunities and threats that can arise from such a micro-cooperation. The research aim is to provide an actor-based, spatially transferable feasibility analysis.
Der Bodensee und das in ihm gespeicherte Wasser dient vielen Zwecken: Neben seiner ökologischen Bedeutung für die Region ist er Trinkwasserquelle und Schifffahrtsweg, wird für Freizeit und Naherholung genutzt. Die Schifffahrt stellt eine der zentralen Attraktionen am Bodensee dar – sie zieht Tagesausflügler und Naherholungssuchende ebenso an wie Urlauber. Der Tourismus ist dabei eine der zentralen Einkommensquellen am Bodensee. Während der Niedrigwasserereignisse der letzten Jahre wurden jedoch die verschiedenen Schifffahrtstypen beeinträchtigt. Dies traf den Tourismus wie auch Berufspendler, Häfen, anliegende Gemeinden und den Gütertransport. Der Beitrag verdeutlicht die Bedeutung der Bodenseeschifffahrt und nennt einige Folgen der Niedrigwasserereignisse der letzten Jahre.
Schon die Römer nutzten die Binnenschifffahrt für den Transport ihrer Güter (SCHRöTER 2005). Noch heute stellt die Binnenschifffahrt auf dem Rhein einen wichtigen Standortfaktor dar, weshalb sich viele Unternehmen, die auf den Transport von Massengütern angewiesen sind, an seinen Ufern niedergelassen haben, um die Binnenschifffahrt als günstiges Transportmittel nutzen zu können (ROTHSTEIN et al. 2009, SCHOLTEN et al. 2009).
Im folgenden Artikel wird sowohl kurz die wirtschaftliche Bedeutung der Binnenschifffahrt auf dem Rhein angesprochen als auch deren rezente und zukünftige Entwicklung. Dabei werden auch die Auswirkungen niedriger Fahrrinnentiefen auf die Transportkapazität der Binnenschifffahrt betrachtet.
Sexistischer Werbung, die gegen die Menschenwürde verstößt, kann über die Auffangnorm des § 3 Abs. 1 UWG bekämpft werden. Dennoch zeigt sich die Rechtsprechung zurückhaltend und stattdessen übernimmt der Deutsche Werberat die Deutungshoheit. Die höchstrichterliche Rechtsprechung konnte sich insoweit bislang nicht fortbilden. Gerade in Zeiten des Wertewandels ist eine aktualisierte höchstrichterliche Rechtsprechung aber nicht zuletzt auch für den Rechtsfrieden unerlässlich.
Digitale Signaturen zum Überprüfen der Integrität von Daten, beispielsweise von Software-Updates, gewinnen zunehmend an Bedeutung. Im Bereich der eingebetteten Systeme kommen derzeit wegen der geringen Komplexität noch überwiegend symmetri-sche Verschlüsselungsverfahren zur Berechnung eines Authentifizierungscodes zum Einsatz. Asym-metrische Kryptosysteme sind rechenaufwendiger, bieten aber mehr Sicherheit, weil der Schlüssel zur Authentifizierung nicht geheim gehalten werden muss. Asymmetrische Signaturverfahren werden typischerweise zweistufig berechnet. Der Schlüssel wird nicht direkt auf die Daten angewendet, sondern auf deren Hash-Wert, der mit Hilfe einer Hash-funktion zuvor berechnet wurde. Zum Einsatz dieser Verfahren in eingebetteten Systemen ist es erforder-lich, dass die Hashfunktion einen hinreichend gro-ßen Datendurchsatz ermöglicht. In diesem Beitrag wird eine effiziente Hardware-Implementierung der SHA-256 Hashfunktion vorgestellt.
Im vorliegenden Aufsatz wird das grundlegende Vorgehen zur Berechnung der Durchbiegung im gerissenen Zustand inklusive Berücksichtigung von Kriechen und Schwinden vorgestellt. Dabei werden aufbauend auf den Vorgaben des EC2 verschiedene Verfahren mit unterschiedlichen Genauigkeitsniveaus für Balken und einachsig gespannte Platten erläutert. Für einfache Systeme können diese Verfahren auch von Hand durchgeführt werden und bieten dabei ein hohes Maß an Kontrolle über den Rechenablauf. Anschließend wird die Ermittlung der Schwindverformungen genauer betrachtet, welche nur mit hohem Rechenaufwand durchgeführt werden kann. Für eine Auswahl von Systemen können Diagramme mit Multiplikationsfaktoren hergeleitet werden, welche die Berechnung stark vereinfachen. Des Weiteren wird auf die Verformungsberechnung im Zustand II für Plattentragwerke eingegangen. Dabei werden sowohl die Berechnung mit FE‐Plattenprogrammen, welche oftmals entsprechende Funktionen anbieten, als auch vereinfachte manuelle Verfahren vorgestellt. Die Grundlagen der Rissbildung lassen sich von Stabtragwerken auf Platten übertragen, allerdings entstehen dabei neue Fragestellungen, wie beispielsweise zum Vorgehen bei der Steifigkeitsabminderung oder zum Einfluss der Schnittgrößenumlagerung infolge Rissbildung. In diesem Bereich besteht daher noch Forschungsbedarf.
Optical surface inspection: A novelty detection approach based on CNN-encoded texture features
(2018)
In inspection systems for textured surfaces, a reference texture is typically known before novel examples are inspected. Mostly, the reference is only available in a digital format. As a consequence, there is no dataset of defective examples available that could be used to train a classifier. We propose a texture model approach to novelty detection. The texture model uses features encoded by a convolutional neural network (CNN) trained on natural image data. The CNN activations represent the specific characteristics of the digital reference texture which are learned by a one-class classifier. We evaluate our novelty detector in a digital print inspection scenario. The inspection unit is based on a camera array and a flashing light illumination which allows for inline capturing of multichannel images at a high rate. In order to compare our results to manual inspection, we integrated our inspection unit into an industrial single-pass printing system.
Offline handwriting recognition systems often use LSTM networks, trained with line- or word-images. Multi-line text makes it necessary to use segmentation to explicitly obtain these images. Skewed, curved, overlapping, incorrectly written text, or noise can lead to errors during segmentation of multi-line text and reduces the overall recognition capacity of the system. Last year has seen the introduction of deep learning methods capable of segmentation-free recognition of whole paragraphs. Our method uses Conditional Random Fields to represent text and align it with the network output to calculate a loss function for training. Experiments are promising and show that the technique is capable of training a LSTM multi-line text recognition system.
Algorithms for calculating the string edit distance are used in e.g. information retrieval and document analysis systems or for evaluation of text recognizers. Text recognition based on CTC-trained LSTM networks includes a decoding step to produce a string, possibly using a language model, and evaluation using the string edit distance. The decoded string can further be used as a query for database search, e.g. in document retrieval. We propose to closely integrate dictionary search with text recognition to train both combined in a continuous fashion. This work shows that LSTM networks are capable of calculating the string edit distance while allowing for an exchangeable dictionary to separate learned algorithm from data. This could be a step towards integrating text recognition and dictionary search in one deep network.
To get a better understanding of Cross Site Scripting vulnerabilities, we investigated 50 randomly selected CVE reports which are related to open source projects. The vulnerable and patched source code was manually reviewed to find out what kind of source code patterns were used. Source code pattern categories were found for sources, concatenations, sinks, html context and fixes. Our resulting categories are compared to categories from CWE. A source code sample which might have led developers to believe that the data was already sanitized is described in detail. For the different html context categories, the necessary Cross Site Scripting prevention mechanisms are described.
We investigated 50 randomly selected buffer overflow vulnerabilities in Firefox. The source code of these vulnerabilities and the corresponding patches were manually reviewed and patterns were identified. Our main contribution are taxonomies of errors, sinks and fixes seen from a developer's point of view. The results are compared to the CWE taxonomy with an emphasis on vulnerability details. Additionally, some ideas are presented on how the taxonomy could be used to improve the software security education.
Research on Shadow IT is facing a conceptual dilemma in cases where previously “covert” systems developed by business entities are integrated in the organizational IT management. These systems become visible, are thus not “in the shadows” anymore, and subsequently do not fit to existing definitions of Shadow IT. Practice shows that some information systems share characteristics of Shadow IT but are created openly in alignment with the IT organization. This paper proposes the term “Business-managed IT” to describe “overt” information systems developed or managed by business entities and distinguishes it from Shadow IT by illustrating case vignettes. Accordingly, our contribution is to suggest a concept and its delineation against other concepts. In this way, IS researchers interested in IT originated from or maintained by business entities can construct theories with a wider scope of application that are at the same time more specific to practical problems. In addition, the terminology allows to value potentially innovative developments by business entities more adequately.
Autonomous moving systems require very detailed information about their environment and potential colliding objects. Thus, the systems are equipped with high resolution sensors. These sensors have the property to generate more than one detection per object per time step. This results in an additional complexity for the target tracking algorithm, since standard tracking filters assume that an object generates at most one detection per object. This requires new methods for data association and system state filtering.
As new data association methods, in this thesis two different extensions of the Joint Integrated Probabilistic Data Association (JIPDA) filter to assign more than one detection to tracks are proposed.
The first method that is introduced, is a generalization of the JIPDA to assign a variable number of measurements to each track based on some predefined statistical models, which will be called Multi Detection - Joint Integrated Probabilistic Data Association (MD-JIPDA).
Since this scheme suffers from exponential increase of association hypotheses, also a new approximation scheme is presented. The second method is an extension for the special case, when the number and locations of measurements are a priori known. In preparation of this method, a new notation and computation scheme for the standard Joint Integrated Data Association is outlined, which also enables the derivation of a new fast approximation scheme called balanced permanent-JIPDA.
For state filtering, also two different concepts are applied: the Random Matrix Framework and the Measurement Generating Points. For the Random Matrix framework, first an alternative prediction method is proposed to account for kinematic state changes in the extension state prediction as well. Secondly, various update methods are investigated to account for the polar to Cartesian noise transformation problem. The filtering concepts are connected with the new MD-JIPDA and their characteristics analyzed with various Monte Carlo simulations.
In case an object can be modeled by a finite number of fixed Measurement Generating Points (MGP), also a proposition to track these object via a JIPDA filter is made. In this context, a fast Track-to-Track fusion algorithm is proposed as well and compared against the MGP-JIPDA.
The proposed algorithms are evaluated in two applications where scanning is done using radar sensors only. The first application is a typical automotive scenario, where a passenger car is equipped with six radar sensors to cover its complete environment.
In this application, the location of the measurements on an object can be considered stationary and that is has a rectangular shape. Thus, the MGP based algorithms are applied here. The filters are evaluated by tracking especially vehicles on nearside lanes.
The second application covers the tracking of vessels on inland waters. Here, two different kind of Radar systems are applied, but for both sensors a uniform distribution of the measurements over the target's extent can be assumed. Further, the assumption that the targets have elliptical shape holds, and so the Random Matrix Framework in combination with the MD-JIPDA is evaluated.
Exemplary test scenarios also illustrate the performance of this tracking algorithm.
A constructive method for the design of nonlinear observers is discussed. To formulate conditions for the construction of the observer gains, stability results for nonlinear singularly perturbed systems are utilised. The nonlinear observer is designed directly in the given coordinates, where the error dynamics between the plant and the observer becomes singularly perturbed by a high-gain part of the observer injection, and the information of the slow manifold is exploited to construct the observer gains of the reduced-order dynamics. This is in contrast to typical high-gain observer approaches, where the observer gains are chosen such that the nonlinearities are dominated by a linear system. It will be demonstrated that the considered approach is particularly suited for self-sensing electromechanical systems. Two variants of the proposed observer design are illustrated for a nonlinear electromagnetic actuator, where the mechanical quantities, i.e. the position and the velocity, are not measured
A constructive nonlinear observer design for self-sensing of digital (ON/OFF) single coil electromagnetic actuators is studied. Self-sensing in this context means that solely the available energizing signals, i.e., coil current and driving voltage are used to estimate the position and velocity trajectories of the moving plunger. A nonlinear sliding mode observer is considered, where the stability of the reduced error dynamics is analyzed by the equivalent control method. No simplifications are made regarding magnetic saturation and eddy currents in the underlying dynamical model. The observer gains are constructed by taking into account some generic properties of the systems nonlinearities. Two possible choices of the observer gains are discussed. Furthermore, an observer-based tracking control scheme to achieve sensorless soft landing is considered and its closed-loop stability is studied. Experimental results for observer-based soft landing of a fast-switching solenoid valve under dry conditions are presented to demonstrate the usefulness of the approach.
Comparison and Identifiability Analysis of Friction Models for the Dither Motion of a Solenoid
(2018)
In this paper, the mechanical subsystem of a proportional solenoid excited by a dither signal is considered. The objective is to find a suitable friction model that reflects the characteristic mechanical properties of the dynamic system. Several different friction models from the literature are compared. The friction models are evaluated with respect to their accuracy as well as their practical identifiability, the latter being quantified based on the Fisher information matrix.
This paper focuses on the multivariable control of a drawing tower process. The nature of the process together with the differences in measurement noise levels that affect the variables to be controlled motivated the development of a new MPC algorithm. An extension of a multivariable predictive control algorithm with separated prediction horizons is proposed. The obtained experimental results show the usefulness of the proposed algorithm..
This paper describes an early lumping approach for generating a mathematical model of the heating process of a moving dual-layer substrate. The heat is supplied by convection and nonlinearly distributed over the whole considered spatial extend of the substrate. Using CFD simulations as a reference, two different modelling approaches have been investigated in order to achieve the most suitable model type. It is shown that due to the possibility of using the transition matrix for time discretization, an equivalent circuit model achieves superior results when compared to the Crank-Nicolson method. In order to maintain a constant sampling time for the in-visioned-control strategies, the effect of variable speed is transformed into a system description, where the state vector has constant length but a variable number of non-zero entries. The handling of the variable transport speed during the heating process is considered as the main contribution of this work. The result is a model, suitable for being used in future control strategies.
Jahresbericht 2018
(2018)