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Accurate monitoring of a patient's heart rate is a key element in the medical observation and health monitoring. In particular, its importance extends to the identification of sleep-related disorders. Various methods have been established that involve sensor-based recording of physiological signals followed by automated examination and analysis. This study attempts to evaluate the efficacy of a non-invasive HR monitoring framework based on an accelerometer sensor specifically during sleep. To achieve this goal, the motion induced by thoracic movements during cardiac contractions is captured by a device installed under the mattress. Signal filtering techniques and heart rate estimation using the symlets6 wavelet are part of the implemented computational framework described in this article. Subsequent analysis indicates the potential applicability of this system in the prognostic domain, with an average error margin of approximately 3 beats per minute. The results obtained represent a promising advancement in non-invasive heart rate monitoring during sleep, with potential implications for improved diagnosis and management of cardiovascular and sleep-related disorders.
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.
The scoring of sleep stages is an essential part of sleep studies. The main objective of this research is to provide an algorithm for the automatic classification of sleep stages using signals that may be obtained in a non-obtrusive way. After reviewing the relevant research, the authors selected a multinomial logistic regression as the basis for their approach. Several parameters were derived from movement and breathing signals, and their combinations were investigated to develop an accurate and stable algorithm. The algorithm was implemented to produce successful results: the accuracy of the recognition of Wake/NREM/REM stages is equal to 73%, with Cohen's kappa of 0.44 for the analyzed 19324 sleep epochs of 30 seconds each. This approach has the advantage of using the only movement and breathing signals, which can be recorded with less effort than heart or brainwave signals, and requiring only four derived parameters for the calculations. Therefore, the new system is a significant improvement for non-obtrusive sleep stage identification compared to existing approaches.
Sustainable technologies are being increasingly used in various areas of human life. While they have a multitude of benefits, they are especially useful in health monitoring, especially for certain groups of people, such as the elderly. However, there are still several issues that need to be addressed before its use becomes widespread. This work aims to clarify the aspects that are of great importance for increasing the acceptance of the use of this type of technology in the elderly. In addition, we aim to clarify whether the technologies that are already available are able to ensure acceptable accuracy and whether they could replace some of the manual approaches that are currently being used. A two-week study with people 65 years of age and over was conducted to address the questions posed here, and the results were evaluated. It was demonstrated that simplicity of use and automatic functioning play a crucial role. It was also concluded that technology cannot yet completely replace traditional methods such as questionnaires in some areas. Although the technologies that were tested were classified as being “easy to use”, the elderly population in the current study indicated that they were not sure that they would use these technologies regularly in the long term because the added value is not always clear, among other issues. Therefore, awareness-raising must take place in parallel with the development of technologies and services.
In order to ensure sufficient recovery of the human body and brain, healthy sleep is indispensable. For this purpose, appropriate therapy should be initiated at an early stage in the case of sleep disorders. For some sleep disorders (e.g., insomnia), a sleep diary is essential for diagnosis and therapy monitoring. However, subjective measurement with a sleep diary has several disadvantages, requiring regular action from the user and leading to decreased comfort and potential data loss. To automate sleep monitoring and increase user comfort, one could consider replacing a sleep diary with an automatic measurement, such as a smartwatch, which would not disturb sleep. To obtain accurate results on the evaluation of the possibility of such a replacement, a field study was conducted with a total of 166 overnight recordings, followed by an analysis of the results. In this evaluation, objective sleep measurement with a Samsung Galaxy Watch 4 was compared to a subjective approach with a sleep diary, which is a standard method in sleep medicine. The focus was on comparing four relevant sleep characteristics: falling asleep time, waking up time, total sleep time (TST), and sleep efficiency (SE). After evaluating the results, it was concluded that a smartwatch could replace subjective measurement to determine falling asleep and waking up time, considering some level of inaccuracy. In the case of SE, substitution was also proved to be possible. However, some individual recordings showed a higher discrepancy in results between the two approaches. For its part, the evaluation of the TST measurement currently does not allow us to recommend substituting the measurement method for this sleep parameter. The appropriateness of replacing sleep diary measurement with a smartwatch depends on the acceptable levels of discrepancy. We propose four levels of similarity of results, defining ranges of absolute differences between objective and subjective measurements. By considering the values in the provided table and knowing the required accuracy, it is possible to determine the suitability of substitution in each individual case. The introduction of a “similarity level” parameter increases the adaptability and reusability of study findings in individual practical cases.
Die Erholung unseres Körpers und Gehirns von Müdigkeit ist direkt abhängig von der Qualität des Schlafes, die aus den Ergebnissen einer Schlafstudie ermittelt werden kann. Die Klassifizierung der Schlafstadien ist der erste Schritt dieser Studie und beinhaltet die Messung von Biovitaldaten und deren weitere Verarbeitung. Das non-invasive Schlafanalyse-System basiert auf einem Hardware-Sensornetz aus 24 Drucksensoren, das die Schlafphasenerkennung ermöglicht. Die Drucksensoren sind mit einem energieeffizienten Mikrocontroller über einen systemweiten Bus mit Adressarbitrierung verbunden. Ein wesentlicher Unterschied dieses Systems im Vergleich zu anderen Ansätzen ist die innovative Art, die Sensoren unter der Matratze zu platzieren. Diese Eigenschaft erleichtert die kontinuierliche Nutzung des Systems ohne fühlbaren Einfluss auf das gewohnte Bett. Das System wurde getestet, indem Experimente durchgeführt wurden, die den Schlaf verschiedener gesunder junger Personen aufzeichneten. Die ersten Ergebnisse weisen auf das Potenzial hin, nicht nur Atemfrequenz und Körperbewegung, sondern auch Herzfrequenz zu erfassen.
The scoring of sleep stages is one of the essential tasks in sleep analysis. Since a manual procedure requires considerable human and financial resources, and incorporates some subjectivity, an automated approach could result in several advantages. There have been many developments in this area, and in order to provide a comprehensive overview, it is essential to review relevant recent works and summarise the characteristics of the approaches, which is the main aim of this article. To achieve it, we examined articles published between 2018 and 2022 that dealt with the automated scoring of sleep stages. In the final selection for in-depth analysis, 125 articles were included after reviewing a total of 515 publications. The results revealed that automatic scoring demonstrates good quality (with Cohen's kappa up to over 0.80 and accuracy up to over 90%) in analysing EEG/EEG + EOG + EMG signals. At the same time, it should be noted that there has been no breakthrough in the quality of results using these signals in recent years. Systems involving other signals that could potentially be acquired more conveniently for the user (e.g. respiratory, cardiac or movement signals) remain more challenging in the implementation with a high level of reliability but have considerable innovation capability. In general, automatic sleep stage scoring has excellent potential to assist medical professionals while providing an objective assessment.
This paper considers intervals of real matrices with respect to partial orders and the problem to infer from some exposed matrices lying on the boundary of such an interval that all real matrices taken from the interval possess a certain property. In many cases such a property requires that the chosen matrices have an identically signed inverse. We also briefly survey related problems, e.g., the invariance of matrix properties under entry-wise perturbations.
This paper considers intervals of real matrices with respect to partial orders and the problem to infer from some exposed matrices lying on the boundary of such an interval that all real matrices taken from the interval possess a certain property. In many cases such a property requires that the chosen matrices have an identically signed inverse. We also briefly survey related problems, e.g., the invariance of matrix properties under entry-wise perturbations.
In this article, the collection of classes of matrices presented in [J. Garloff, M. Adm, ad J. Titi, A survey of classes of matrices possessing the interval property and related properties, Reliab. Comput. 22:1-14, 2016] is continued. That is, given an interval of matrices with respect to a certain partial order, it is desired to know whether a special property of the entire matrix interval can be inferred from some of its element matrices lying on the vertices of the matrix interval. The interval property of some matrix classes found in the literature is presented, and the interval property of further matrix classes including the ultrametric, the conditionally positive semidefinite, and the infinitely divisible matrices is given for the first time. For the inverse M-matrices the cardinality of the required set of vertex matrices known so far is significantly reduced.
We provide an overview of the ongoing discussions on the objectives of the energy transition in the form of a conceptual framework, intending to facilitate the search for the most viable options for a successful transformation of the energy system. For this purpose, we examine the development of energy policy goals in Germany in the past and present, whereby we give an overview of objectives and assessment approaches from politics, economics, and science. Moreover, we then merge the different views into a common framework and analyze the central conflict between the wholeness of a hypothetical target circle and the simplification in favor of a hypothetical target point in more detail.
In this paper, the problem of controlling the dissolved oxygen level (DO) during an aerobic fermentation is considered. The proposed approach deals with three major difficulties in respect to the nonlinear dynamics of the DO, the poor accuracy of the empirical models for the oxygen consumption rate and the fact that only sampled measurements are available on-line. A nonlinear integral high-gain control law including a continuous-discrete time observer is designed to keep the DO in the neighborhood of a set point value without any knowledge on the dissolved oxygen consumption rate. The local stability of the control algorithm is proved using Lyapunov tools. The performance of the control scheme is first analyzed in simulation and then experimentally evaluated during a successfull fermentation of the bacteria over a period of three days. Pseudomonas putida mt-2
3-Stufen-Pulswechselrichter
(2016)
Domain-Specific modelling is increasingly adopted in the software development industry. While textual domain specific languages (DSLs) already have a wide impact, graphical DSLs still need to live up to their full potential. In this paper we describe an approach that reduces the time to create a graphical DSL to hours instead of months. The paper describes a generative approach to the creation of graphical editors for the Eclipse platform. A set of carefully designed textual DSLs together with an EMF meta-model are the input for the generator. The output is an Eclipse plugin for a graphical editor for the intended graphical language. The entire project is made available as open source under the name Spray and is being developed by an active community. This paper focuses on the description of the workflow and provides an introduction into the possibilities through this approach of a graphical modelling environment.
Domain-specific modeling is more and more understood as a comparable solution compared to classical software development. Textual domain-specific languages (DSLs) already have a massive impact in contrast tographical DSLs, they still have to show their full potential. The established textual DSLs are normally generated from a domain specific grammar or maybe other specific textual descriptions. And advantage of textual DSLs is that they can be development cost-efficient.
In this paper, we describe asimilar approach for the creation of graphical DSLs from textual descriptions. We present a set of specially developed textual DSLs to fully describe graphical DSLs based on node and edge diagrams. These are, together with an EMF meta-model, the input for a generator that produces an eclipse-based graphical Editor. The entire project is available as open source under the name MoDiGen.
Domain-specific modeling is increasingly adopted in the software development industry. While textual domain-specific languages (DSLs) already have a wide impact, graphical DSLs still need to live up to their full potential. In this paper, we describe an approach to automatically generate a graphical DSL from a set of textual languages. With our approach, node and edge type graphical DSLs can be described using textual models. A set of carefully designed textual DSLs is the input for our generators. The result of the generation is a graphical editor for the intended domain. The development time for a graphical editor is reduced significantly. The whole project is available as open source under the name "Zeta". This publication focuses on the explanation of the textual DSLs for defining a graphical node and edge editor.
Domain-specific modeling is increasingly adopted by the software development industry. While textual domain-specific languages (DSLs) already have a wide impact, graphical DSLs still need to live up to their full potential. Textual DSLs are usually generated from a grammar or other short textual notations; their development is often cost-efficient. In this paper, we describe an approach to similarly create graphical DSLs from textual notations. The paper describes an approach to generate a graphical node and edge online editor, using a set of carefully designed textual DSLs to fully describe graphical DSLs. Combined with an adequate metamodel, these textual definitions represent the input for a generator that produces a graphical Editor for the web with features such as collaboration, online storage and being always available. The entire project is made available as open source under the name Zeta. This paper focuses on the overall approach and the description of the textual DSLs that can be used to develop graphical modeling languages and editors.
What drives entrepreneurial action to create a lasting impact? The creation of new ventures that aim at having an impact beyond their financial performance face additional challenges: achieving economic sustainability and at the same time addressing social or environmental issues. Little is known on how these new hybrid organizations, aiming for multiple impact dimensions, manage to be congruent with their blended values. A dataset of 4,125 early-stage ventures is used to gain insights into how blended values are converted into financial, social and environmental impacts, giving shape to different types of hybrid organizations. Our findings suggest new hybrid organizations might opt to sacrifice financial impact to achieve social impact, yet this is not the case when they aim to generate environmental or sustainable impact. Therefore, the tensions and sacrifices related to holding blended values are not homogeneous across all types of new hybrid organizations.
Anthropologists’ arrival stories have long served to justify, naturalize, and domesticate—often through humor—the fraught moment of entering unasked into other people's lives. This textual convention has been thoroughly critiqued, but no comparable attention has been paid to the analogous moment of departure from the field. The digital age enables both sides to maintain contact, a shift that negates the finality of earlier departures. This article engages the changes wrought by digital media that allow us to remain connected to the field. While this seems a humane affordance, it also means that it is no longer feasible to cleanly sever ties established ‘there’. When anthropologists leave the field, the field will likely follow them—on Facebook or Instagram.
Die Kleinwasserkraft stand zuletzt zunehmend in der öffentlichen Kritik wegen des ökologischen Einflusses und der verhältnismäßigen geringen Stromerzeugung. Der vorliegende Beitrag beschreibt die Einschätzung von KWK-Betreibern zum Potenzial einer Effizienzsteigerung ihrer bestehenden Anlagen durch eine intelligente Informationsvernetzung innerhalb des Flusslaufes der Radolfzeller Aach im Süden Baden-Württembergs, um somit die Stromerzeugung der einzelnen Anlagen zu erhöhen.
This work studies a wind noise reduction approach for communication applications in a car environment. An endfire array consisting of two microphones is considered as a substitute for an ordinary cardioid microphone capsule of the same size. Using the decomposition of the multichannel Wiener filter (MWF), a suitable beamformer and a single-channel post filter are derived. Due to the known array geometry and the location of the speech source, assumptions about the signal properties can be made to simplify the MWF beamformer and to estimate the speech and noise power spectral densities required for the post filter. Even for closely spaced microphones, the different signal properties at the microphones can be exploited to achieve a significant reduction of wind noise. The proposed beamformer approach results in an improved speech signal regarding the signal-to-noise-ratio and keeps the linear speech distortion low. The derived post filter shows equal performance compared to known approaches but reduces the effort for noise estimation.
The multichannel Wiener filter (MWF) is a well-established noise reduction technique for speech processing. Most commonly, the speech component in a selected reference microphone is estimated. The choice of this reference microphone influences the broadband output signal-to-noise ratio (SNR) as well as the speech distortion. Recently, a generalized formulation for the MWF (G-MWF) was proposed that uses a weighted sum of the individual transfer functions from the speaker to the microphones to form a better speech reference resulting in an improved broadband output SNR. For the MWF, the influence of the phase reference is often neglected, because it has no impact on the narrow-band output SNR. The G-MWF allows an arbitrary choice of the phase reference especially in the context of spatially distributed microphones.
In this work, we demonstrate that the phase reference determines the overall transfer function and hence has an impact on both the speech distortion and the broadband output SNR. We propose two speech references that achieve a better signal-to-reverberation ratio (SRR) and an improvement in the broadband output SNR. Both proposed references are based on the phase of a delay-and-sum beamformer. Hence, the time-difference-of-arrival (TDOA) of the speech source is required to align the signals. The different techniques are compared in terms of SRR and SNR performance.
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.
FishNet
(2016)
Compliance Essentials
(2017)
Compliance Management ist längst zu einem Thema in mittelständischen Unternehmen geworden. Aber was ist der richtige Ansatz, um Regeleinhaltung, Rechtschaffenheit und verantwortliches Wirtschaften als Unternehmer oder Unternehmenslenker wirksam und effizient zu organisieren? Welche Rolle spielen die Führungskräfte? Ausgehend von der Frage, was ein mittelständisch geprägtes Unternehmen im Bereich der Compliance tun kann und soll und dem dazu gehörenden Compliance Management System, wird in diesem Beitrag knapp umrissen, worauf es bei der Implementierung und Umsetzung von Maßnahmen im Unternehmensalltag besonders ankommt. Dabei wird der Schulung der Führungskräfte mittels qualitativ hochwertiger Dilemma-Trainings ein ebenso hoher Stellenwert eingeräumt, wie der auch dadurch sukzessive zu entwickelnden ethischen Unternehmenskultur.
Integritätsmanagement
(2016)
Compliance hat in der Vergangenheit oftmals versagt, der aktuelle „VW-Abgasskandal“ ist nur ein Beispiel. Es muss nicht alles neu erfunden werden, und nicht alles, was Unternehmen in der Vergangenheit im Bereich Compliance taten, ist schlecht. Aber es ist an der Zeit, Compliance neu zu denken. Worauf kommt es wirklich an im Compliance Management 2.0? Meine Antwort lautet, dass Ernsthaftigkeit und Glaubwürdigkeit gefördert werden müssen und gefördert werden können. Wie, das versuche ich im Rahmen von sechs Thesen zu skizzieren.
In einem Expertengespräch tauschen sich Herr Michael Kayser, Geschäftsführer der digital spirit GmbH und Herr Prof. Dr. Stephan Grüninger, Direktor des Center for Business Compliance & Integrity (CBCI) an der Hochschule Konstanz, zur neuen ISO 19600 “Compliance Management Systems” aus. Das Gespräch wurde von Frau Sabrina Quintus, Akademische Mitarbeiterin am CBCI, geleitet.
Rethinking Compliance
(2017)
In the past Compliance Management has often failed, the Volkswagen emissions scandal just being one prominent example. Not everything has to be reinvented, and not everything that companies have done in the past regarding Compliance is wrong. But it is about time to think Compliance in new ways. What does “Compliance Management 2.0” really depend on? The following article aims at laying out the cornerstones for enduring effective Compliance which amongst others comprises sincerity and credibility and a moral foundation. Furthermore, the commitment and role model behavior of top managers and the training of line managers are crucial for the effectiveness of any Compliance Management System (CMS). Ultimately, for Compliance to function efficiently the efforts must be adequate for the respective company and realistic regarding the achievable goals.
Der Begriff "Integrität" nimmt das Verhältnis zwischen individuellem Handeln und der Einhaltung von Regeln und Werten in den Blick. Grüninger/Wanzek betonen, dass integres Handeln nicht blinde Regelbefolgung, sondern die Erfüllung der zugrundeliegenden Werte erfordert. Von Integrität wird gesprochen, wenn die ethischen Werte im individuellen Denken und Tun sowie auf persönlicher und organisationaler Ebene übereinstimmen.
Compliance wirkt, wenn sie in den Köpfen der Menschen ankommt – und wenn sie adaptiv die Themen der Zeit aufgreift.
Eine Führungskräftebefragung der Kommunikationsagentur A&B One, unterstützt vom Zentrum für Wirtschaftsethik (ZfW), zeichnet hierzu ein aktuelles Bild der wichtigen Zielgruppe “Management”. Der Beitrag skizziert die Sicht von Führungsverantwortlichen aller Ebenen auf die viel diskutierte unternehmerische Verantwortung, auf die Wirksamkeit von Compliance-Maßnahmen und auf Compliance-Risiken im Homeoffice. Er gibt Impulse für die Praxis: von Synergien zwischen Purpose und Integrität bis hin zur Förderung von Regelbewusstsein beim (coronabedingten) Remote Working.
Multistakeholder-Analyse zur Evaluation der KiCG Anforderungen an Compliance-Management-Systeme
(2015)
As organizations struggle to cope with digital transformation in
an innovation environment, partnerships between startups and established
companies have become increasingly important. Building upon years of
practical experience and empirical research, we present advantages,
obstacles, and the keys to successful corporate-startup collaboration.
40 Jahre Neuland des Denkens
(2020)
Vor 40 Jahren erschien Frederic Vesters Hauptwerk „Neuland des Denkens“. Der Beitrag beleuchtet die wesentlichen Themen dieses programmatischen Buches im Hinblick auf Vesters Biokybernetik und deren Anwendung auf zahlreiche aktuelle Fragen in der Nachhaltigkeits-Debatte, z.B. Klimawandel-Problematik und Energiewende.
Moderne politische Steuerungskonzeptionen zeichnen sich dadurch aus, dass sie zum einen die Mängel traditioneller planungszentrierter Konzepte vermeiden und zum anderen der gewachsenen Vielfalt an Kooperationsmöglichkeiten unterschiedlicher Akteurssysteme gerecht werden. Speziell für das Handlungsfeld der kommunalen Energiewende führt dies zu einer Governance-Konzeption, bei der Kommunen als systemische Steuerungsakteure fungieren. Hierbei moderieren und gestalten sie zusammen mit den relevanten Akteuren die verschiedenen Herausforderungen im Rahmen kommunaler Energiewendekonzepte.
Lignin is a potentially high natural source of biological aromatic substances. However, decomposition of the polymer has proven to be quite challenging, as the complex bonds are fairly difficult to break down chemically. This article is intended to provide an overview of various recent methods for the catalytic chemical depolymerization of the biopolymer lignin into chemical products. For this purpose, nickel-, zeolite- and palladium-supported catalysts were examined in detail. In order to achieve this, various experiments of the last years were collected, and the efficiency of the individual catalysts was examined. This included evaluating the reaction conditions under which the catalysts work most efficiently. The influence of co-catalysts and Lewis acidity was also investigated. The results show that it is possible to control the obtained product selectivity very well by the choice of the respective catalysts combined with the proper reaction conditions.
Durch eine Aufweitung des Kristallgitters mittels Niedertemperatur-Eindiffusion von Kohlenstoff und/oder Stickstoffatomen können in der Randzone von nichtrostenden Stählen eine hohe Härte und eine hohe Verschleißbeständigkeit erzeugt werden, ohne dass zusätzliche Legierungselemente verwendet werden müssen. Die metallkundlichen Hintergründe für die Härtung, die Wirkung auf Verschleißvorgänge und mögliche Anwendungsbereiche werden geschildert. Anhand von Reibwerten wird gezeigt, in welcher Weise das Reibungsverhalten bei Schraubverbindungen durch die Behandlung verändert wird. Über Migrationsversuche wird nachgewiesen, dass die Ionenabgabe durch die Oberflächenhärtung nicht erhöht, sondern sogar abgesenkt wird. Neben dem besseren Verschleißschutz und einer höheren Dauerfestigkeit sichert diese Oberflächenbehandlung am nichtrostenden Stahl den Schutz gegen die Kontamination von Pharmaprodukten durch Metallabrieb/-ionen. Tests an oberflächengehärteten Edelstahlproben ergaben weiterhin, dass durch die Oberflächenhärtung die Biokompatibilität des nichtrostenden Edelstahls nicht beeinträchtigt wird.
The corrosion resistance of stainless steels is massively influenced by the condition of their surface. The surface quality includes the topography of the surface, the structure and composition of the passive layer, and the surface near structure of the base material. These factors are influenced by final physical/chemical surface treatments. The presented work shows significantly lower corrosion resistance for mechanical machined specimens than for etched specimens. It also turns out that the rougher the surface, the lower the corrosion resistance gets. However, there is no general finding which shows if blasted or grinded surfaces are more appropriate, but a dependency on process parameters and the characteristics on corrosive exposure in terms of corrosion behavior. The results show that not only the surface roughness Ra has an influence on corrosion behavior but also the shape of peaks and valleys which are evolved by surface treatments. Imperfections in the base material, like sulfidic inclusions lead to a weaker passive layer, respectively, to a decrease of the corrosion resistance. By using special passivating techniques the corrosion resistance of stainless steels can be increased to a higher level in comparison to common passivation.
The project aims for the development of a new material system from high tensile stainless steel wires as net material with environmentally compatible antifouling properties for off-shore fish farm cages. Therefore, current net materials from textiles (polyamide) shall be partially replaced by high strength stainless steel in order to have a more environmentally compatible system which meets the more severe mechanical loads (waves, storms, predators (sharks)). With a new antifouling strategy current issues like reduced ecological damage (e.g. due to copper disposal), lower maintenance costs (e.g. cleaning) and reduced durability shall be resolved.
Compliance und Compliance-Management sind als Schlagworte mittlerweile fest in das alltägliche unternehmerische Handeln und Denken integriert. Ausgehend von der unternehmerischen Legalitätspflicht und dem Bedürfnis nach Haftungsvermeidung durch bestmögliche Organisation liegt es nahe, dass Unternehmen, Unternehmer und Führungskräfte ein Bedürfnis nach rechtssicherem Agieren in einem rechtssicheren Umfeld haben. Ob und inwiefern hieraus eine Rechtspflicht zur Errichtung einer Compliance-Organisation bzw. eines Compliance-Management-Systems (CMS) abzuleiten ist, ist allerdings jedenfalls auf den ersten Blick nach wie vor unklar. Ob es sich bei der Einführung eines CMS bzw. einer Compliance-Organisation um eine nur angezeigte Notwendigkeit oder aber eine rechtliche Pflicht handelt, lässt sich anhand der bisherigen Entwicklung in Literatur und Rechtsprechung mittlerweile recht eindeutig beantworten.
Compliance im Mittelstand
(2016)
Die Etablierung eines Compliance-Management-Systems (CMS) stößt v. a. im Mittelstand immer wieder auf teils erheblichen (kosten- wie kulturbedingten) Widerstand. Der nachfolgende Beitrag erläutert Motive und Gründe zur Einrichtung eines CMS, welches eine systematische Sicherstellung der Einhaltung von geltenden Gesetzen sowie internen Vorgaben gewährleisten soll, um Unternehmen und deren Organe sowie Mitarbeiter vor rechtlichen Risiken zu schützen.
Business Partner Compliance
(2022)
Die jüngeren Entscheidungen des EuGH sowie des BAG zur Arbeitszeiterfassung haben trotz ihrer eigentlich klaren Aussagen in der betrieblichen Praxis zu teils erheblichen Verunsicherungen geführt: Müssen nun wirklich die Arbeitszeiten der Beschäftigten erfasst werden und wie wirkt sich das auf die in vielen Unternehmen gelebte „Vertrauensarbeitszeit“ aus?
Compliance im Personalwesen
(2019)
Der Erfolg eines Unternehmens hängt nicht nur von qualifizierten, sondern maßgeblich auch von motivierten, zuverlässigen und integren Mitarbeitern ab. Denn mögliche Compliance-Risiken beruhen in vielen Fällen auf einem Fehlverhalten der eigenen Mitarbeiter. Derartige Risiken können sehr einfach minimiert werden, indem von vornherein keine Personen eingestellt oder befördert werden, die in der Vergangenheit straffällig geworden sind oder deren Zuverlässigkeit und Integrität angezweifelt werden kann. Doch nicht immer ist die Sachlage so offensichtlich. Für Unternehmen ist es daher wichtig, Compliance auch im Personalmanagement und in den Personalprozessen zu berücksichtigen und zu integrieren.
Die Relevanzanalyse
(2023)
Ordnungsgemäße Unternehmensführung ohne adäquates Risiko- und Compliance-Management ist kaum noch vor- und darstellbar. Rechtsprechung, Literatur, Politik und Gesellschaft stellen (mehr oder weniger) klare Anforderungen an ordnungsgemäßes unternehmerisches Verhalten und sanktionieren tatsächliche (und vermeintliche) Regelverstöße. Um die unternehmensspezifischen Risiken zu erfassen ist die Durchführung einer Risikoanalyse (Compliance Risk Assessment – CRA) unumgänglich1. Der eigentlichen Risikoanalyse ist eine Relevanzanalyse voranzustellen, um sich der bei unternehmerischen Aktivitäten naturgemäß nahezu unüberschaubaren potenziellen Risikomenge anzunähern und diese „abarbeitbar“ zu erfassen. Wird diese Relevanzanalyse professionell und strukturiert durchgeführt und dokumentiert, so kann sie einen wertvollen Beitrag zum Schutz und zur Hilfe gegen Compliance-Verstöße und deren Sanktionierung leisten. Der nachfolgende Beitrag stellt die Grundlagen, Ziele, Anforderungen und Ansätze der Relevanzanalyse dar. In einem weiteren Beitrag (erscheint in CB 11/2023) werden sich die Autoren der Durchführung der Relevanzanalyse widmen und Hinweise zu deren Ablauf und Inhalt geben.
Die Relevanzanalyse
(2023)
Um unternehmensspezifische Risiken zu erfassen ist die Risikoanalyse unumgänglich. Ihr ist wiederum eine Relevanzanalyse voranzustellen. Nachdem im Heft 10 des Compliance Berater 2023, S. 400-404 die Grundlagen, Ziele, Anforderungen und Ansätze der Relevanzanalyse dargestellt wurden, widmet sich der nachfolgende Beitrag der Durchführung der Relevanzanalyse und gibt Hinweise zu deren Ablauf und Inhalt.
Urlaub, Urlaub und kein Ende – Die aktuelle Rechtslage auf Basis der Rechtsprechung von EuGH und BAG
(2023)
Teilzeitmodelle sind beliebt und haben für viele Mitarbeiter einen ernsten Hintergrund. Ihre Lebensentwürfe lassen schlicht keine andere Form der Arbeit zu. Arbeitgeber sollten einerseits auf die Flexibilisierungswünsche der Betroffenen eingehen, um das Betriebsklima zu fördern und eine Unternehmensbindung herzustellen. Andererseits sind sie aber (mit wenigen Ausnahmen) verpflichtet, Teilzeit zu ermöglichen. Eine Variante ist dabei die Brückenteilzeit, also eine zuvor festgelegte (nur) zeitlich begrenzte Verringerung der Arbeitszeit.
Sanktionen gegen Russland
(2023)
Die EU hat aufgrund des völkerrechtswidrigen Angriffskrieges auf die Ukraine umfangreiche Sanktionen gegen Russland erlassen. Die Sanktionspakete umfassen insbesondere Wirtschaftssanktionen in Form von Einfuhr- und Ausfuhrbeschränkungen, die für deutsche Unternehmen mit unmittelbaren oder mittelbaren Geschäftsbeziehungen nach Russland von Bedeutung sind. Im Vordergrund der rechtlichen Thematik steht die Frage, ob und wann deutsche Unternehmen gegen EU-Sanktionen verstoßen. Aber auch deutsche Unternehmen mit Tochtergesellschaften in Drittstaaten stehen vor der großen Herausforderung, den Regelmechanismus der diversen Sanktionspakete zu durchleuchten, um sich nicht der Gefahr des Vorwurfs einer Umgehung der Sanktionen auszusetzen.
Even though immutability is a desirable property, especially in a multi-threaded environment, implementing immutable Java classes is surprisingly hard because of a lack of language support. We present a static analysis tool using abstract bytecode interpretation that checks Java classes for compliance with a set of rules that together constitute state-based immutability. Being realized as a Find Bugs plug in, the tool can easily be integrated into most IDEs and hence the software development process. Our evaluation on a large, real world codebase shows that the average run-time effort for a single class is in the range of a few milliseconds, with only a very few statistical spikes.
Aufgrund der Corona-Pandemie kam es 2020 zu einer verstärkten Nutzung von Homeoffice und Teleworking. Sowohl bzgl. der Wahl des Arbeitsortes als auch der genutzen Kommunikationstechnologien existieren Pfadabhängigkeiten. Der Beitrag thematisiert diese Pfadabhängigkeiten systematisch, insbesondere ihre Ursachen und Folgen sowie die Möglichkeiten zur Pfadbrechung.
Sleep disorders can impact daily life, affecting physical, emotional, and cognitive well-being. Due to the time-consuming, highly obtrusive, and expensive nature of using the standard approaches such as polysomnography, it is of great interest to develop a noninvasive and unobtrusive in-home sleep monitoring system that can reliably and accurately measure cardiorespiratory parameters while causing minimal discomfort to the user’s sleep. We developed a low-cost Out of Center Sleep Testing (OCST) system with low complexity to measure cardiorespiratory parameters. We tested and validated two force-sensitive resistor strip sensors under the bed mattress covering the thoracic and abdominal regions. Twenty subjects were recruited, including 12 males and 8 females. The ballistocardiogram signal was processed using the 4th smooth level of the discrete wavelet transform and the 2nd order of the Butterworth bandpass filter to measure the heart rate and respiration rate, respectively. We reached a total error (concerning the reference sensors) of 3.24 beats per minute and 2.32 rates for heart rate and respiration rate, respectively. For males and females, heart rate errors were 3.47 and 2.68, and respiration rate errors were 2.32 and 2.33, respectively. We developed and verified the reliability and applicability of the system. It showed a minor dependency on sleeping positions, one of the major cumbersome sleep measurements. We identified the sensor under the thoracic region as the optimal configuration for cardiorespiratory measurement. Although testing the system with healthy subjects and regular patterns of cardiorespiratory parameters showed promising results, further investigation is required with the bandwidth frequency and validation of the system with larger groups of subjects, including patients.
Recognizing Human Activity of Daily Living Using a Flexible Wearable for 3D Spine Pose Tracking
(2023)
The World Health Organization recognizes physical activity as an influencing domain on quality of life. Monitoring, evaluating, and supervising it by wearable devices can contribute to the early detection and progress assessment of diseases such as Alzheimer’s, rehabilitation, and exercises in telehealth, as well as abrupt events such as a fall. In this work, we use a non-invasive and non-intrusive flexible wearable device for 3D spine pose measurement to monitor and classify physical activity. We develop a comprehensive protocol that consists of 10 indoor, 4 outdoor, and 8 transition states activities in three categories of static, dynamic, and transition in order to evaluate the applicability of the flexible wearable device in human activity recognition. We implement and compare the performance of three neural networks: long short-term memory (LSTM), convolutional neural network (CNN), and a hybrid model (CNN-LSTM). For ground truth, we use an accelerometer and strips data. LSTM reached an overall classification accuracy of 98% for all activities. The CNN model with accelerometer data delivered better performance in lying down (100%), static (standing = 82%, sitting = 75%), and dynamic (walking = 100%, running = 100%) positions. Data fusion improved the outputs in standing (92%) and sitting (94%), while LSTM with the strips data yielded a better performance in bending-related activities (bending forward = 49%, bending backward = 88%, bending right = 92%, and bending left = 100%), the combination of data fusion and principle components analysis further strengthened the output (bending forward = 100%, bending backward = 89%, bending right = 100%, and bending left = 100%). Moreover, the LSTM model detected the first transition state that is similar to fall with the accuracy of 84%. The results show that the wearable device can be used in a daily routine for activity monitoring, recognition, and exercise supervision, but still needs further improvement for fall detection.
Apnea is a sleep disorder characterized by breathing interruptions during sleep, impacting cardiorespiratory function and overall health. Traditional diagnostic methods, like polysomnography (PSG), are unobtrusive, leading to noninvasive monitoring. This study aims to develop and validate a novel sleep monitoring system using noninvasive sensor technology to estimate cardiorespiratory parameters and detect sleep apnea. We designed a seamless monitoring system integrating noncontact force-sensitive resistor sensors to collect ballistocardiogram signals associated with cardiorespiratory activity. We enhanced the sensor’s sensitivity and reduced the noise by designing a new concept of edge-measuring sensor using a hemisphere dome and mechanical hanger to distribute the force and mechanically amplify the micromovement caused by cardiac and respiration activities. In total, we deployed three edge-measuring sensors, two deployed under the thoracic and one under the abdominal regions. The system is supported with onboard signal preprocessing in multiple physical layers deployed under the mattress. We collected the data in four sleeping positions from 16 subjects and analyzed them using ensemble empirical mode decomposition (EMD) to avoid frequency mixing. We also developed an adaptive thresholding method to identify sleep apnea. The error was reduced to 3.98 and 1.43 beats/min (BPM) in heart rate (HR) and respiration estimation, respectively. The apnea was detected with an accuracy of 87%. We optimized the system such that only one edge-measuring sensor can measure the cardiorespiratory parameters. Such a reduction in the complexity and simplification of the instruction of use shows excellent potential for in-home and continuous monitoring.
Image novelty detection is a repeating task in computer vision and describes the detection of anomalous images based on a training dataset consisting solely of normal reference data. It has been found that, in particular, neural networks are well-suited for the task. Our approach first transforms the training and test images into ensembles of patches, which enables the assessment of mean-shifts between normal data and outliers. As mean-shifts are only detectable when the outlier ensemble and inlier distribution are spatially separate from each other, a rich feature space, such as a pre-trained neural network, needs to be chosen to represent the extracted patches. For mean-shift estimation, the Hotelling T2 test is used. The size of the patches turned out to be a crucial hyperparameter that needs additional domain knowledge about the spatial size of the expected anomalies (local vs. global). This also affects model selection and the chosen feature space, as commonly used Convolutional Neural Networks or Vision Image Transformers have very different receptive field sizes. To showcase the state-of-the-art capabilities of our approach, we compare results with classical and deep learning methods on the popular dataset CIFAR-10, and demonstrate its real-world applicability in a large-scale industrial inspection scenario using the MVTec dataset. Because of the inexpensive design, our method can be implemented by a single additional 2D-convolution and pooling layer and allows particularly fast prediction times while being very data-efficient.
At present, the majority of the proposed Deep Learning (DL) methods provide point predictions without quantifying the model's uncertainty. However, a quantification of the reliability of automated image analysis is essential, in particular in medicine when physicians rely on the results for making critical treatment decisions. In this work, we provide an entire framework to diagnose ischemic stroke patients incorporating Bayesian uncertainty into the analysis procedure. We present a Bayesian Convolutional Neural Network (CNN) yielding a probability for a stroke lesion on 2D Magnetic Resonance (MR) images with corresponding uncertainty information about the reliability of the prediction. For patient-level diagnoses, different aggregation methods are proposed and evaluated, which combine the individual image-level predictions. Those methods take advantage of the uncertainty in the image predictions and report model uncertainty at the patient-level. In a cohort of 511 patients, our Bayesian CNN achieved an accuracy of 95.33% at the image-level representing a significant improvement of 2% over a non-Bayesian counterpart. The best patient aggregation method yielded 95.89% of accuracy. Integrating uncertainty information about image predictions in aggregation models resulted in higher uncertainty measures to false patient classifications, which enabled to filter critical patient diagnoses that are supposed to be closer examined by a medical doctor. We therefore recommend using Bayesian approaches not only for improved image-level prediction and uncertainty estimation but also for the detection of uncertain aggregations at the patient-level.
Extended Target Tracking With a Lidar Sensor Using Random Matrices and a Virtual Measurement Model
(2022)
Random matrices are widely used to estimate the extent of an elliptically contoured object. Usually, it is assumed that the measurements follow a normal distribution, with its standard deviation being proportional to the object’s extent. However, the random matrix approach can filter the center of gravity and the covariance matrix of measurements independently of the measurement model. This work considers the whole chain from data acquisition to the linear Kalman Filter with extension estimation as a reference plant. The input is the (unknown) ground truth (position and extent). The output is the filtered center of gravity and the filtered covariance matrix of the measurement distribution. A virtual measurement model emulates the behavior of the reference plant. The input of the virtual measurement model is adapted using the proposed algorithm until the output parameters of the virtual measurement model match the result of the reference plant. After the adaptation, the input to the virtual measurement model is considered an estimation for position and extent. The main contribution of this paper is the reference model concept and an adaptation algorithm to optimize the input of the virtual measurement model.
In this paper, a novel feature-based sampling strategy for nonlinear Model Predictive Path Integral (MPPI) control is presented. Using the MPPI approach, the optimal feedback control is calculated by solving a stochastic optimal control (OCP) problem online by evaluating the weighted inference of sampled stochastic trajectories. While the MPPI algorithm can be excellently parallelized, the closed-loop performance strongly depends on the information quality of the sampled trajectories. To draw samples, a proposal density is used. The solver’s and thus, the controller’s performance is of high quality if the sampled trajectories drawn from this proposal density are located in low-cost regions of state-space. In classical MPPI control, the explored state-space is strongly constrained by assumptions that refer to the control value’s covariance matrix, which are necessary for transforming the stochastic Hamilton–Jacobi–Bellman (HJB) equation into a linear second-order partial differential equation. To achieve excellent performance even with discontinuous cost functions, in this novel approach, knowledge-based features are introduced to constitute the proposal density and thus the low-cost region of state-space for exploration. This paper addresses the question of how the performance of the MPPI algorithm can be improved using a feature-based mixture of base densities. Furthermore, the developed algorithm is applied to an autonomous vessel that follows a track and concurrently avoids collisions using an emergency braking feature. Therefore, the presented feature-based MPPI algorithm is applied and analyzed in both simulation and full-scale experiments.
The problem of vessel collisions or near-collision situations on sea, often caused by human error due to incomplete or overwhelming information, is becoming more and more important with rising maritime traffic. Approaches to supply navigators and Vessel Traffic Services with expert knowledge and suggest trajectories for all vessels to avoid collisions, are often aimed at situations where a single planner guides all vessels with perfect information. In contrast, we suggest a two-part procedure which plans trajectories using a specialised A* and negotiates trajectories until a solution is found, which is acceptable for all vessels. The solution obeys collision avoidance rules, includes a dynamic model of all vessels and negotiates trajectories to optimise globally without a global planner and extensive information disclosure. The procedure combines all components necessary to solve a multi-vessel encounter and is tested currently in simulation and on several test beds. The first results show a fast converging optimisation process which after a few negotiation rounds already produce feasible, collision free trajectories.
Durch die zunehmende Vernetzung und den Anstieg von eingesetzter Hard- und Software hat sich die Komplexität der Unternehmensarchitektur von Unternehmen über die Jahre stetig erhöht. Das Aufkommen nutzerfreundlicher Informationstechnologie (IT)-Lösungen befähigt außerdem Fachbereiche, IT innovativ einzusetzen. Dies erhöht die Heterogenität und damit nochmals die Komplexität der Unternehmensarchitektur. Darüber hinaus treibt dieser IT-Einsatz die Digitalisierung in den Unternehmen maßgeblich voran. Dies wirft die Frage auf, ob Unternehmen überhaupt noch eine Relevanz in der Reduktion der Komplexität durch IT-Integration sehen oder ob dies vor dem Hintergrund der Digitalisierung schon ein alter Hut ist. Experteninterviews und eine qualitative Datenanalyse zeigen, dass IT-Integration und Digitalisierung keine disjunkten Phänomene sind, sondern sich gegenseitig beeinflussen. Die Ergebnisse betonen, wie unterschiedlich der Begriff aufgefasst werden kann und dass die einheitliche Nutzung damit essenziell ist. Darüber hinaus zeigen sie, dass Digitalisierung einerseits Treiber der IT-Integration ist, andererseits aber auch die Möglichkeiten zur Umsetzung verändert. Dabei ist die Integrationsentscheidung durch die Vielzahl an Vor- und Nachteile komplex. Fachbereichs-IT ist selten explizites Ziel von IT-Integrationsprojekten. Der Beitrag zeigt den wissenschaftlichen Forschungsbedarf in neuen technologischen Möglichkeiten zur IT-Integration und in der Balance von Flexibilität und IT-Integration in der Unternehmensarchitektur. Er beleuchtet, dass eine gemeinsame Sprache die Basis für IT-Integrationsprojekte ist und dass eine Kultur, in der Fachbereiche aktiv an IT-Integrationsentscheidungen teilhaben, das Ziel eines jeden Unternehmens sein sollte. Insgesamt zeigen die Analysen, dass IT-Integration noch lange kein alter Hut, sondern, im Gegenteil, brandaktuell ist.
Business units are increasingly able to fuel the transformation that digitalization demands of organizations. Thereby, they can implement Shadow IT (SIT) without involving a central IT department to create flexible and innovative solutions. Self-reinforcing effects lead to an intertwinement of SIT with the organization. As a result, high complexities, redundancies, and sometimes even lock-ins occur. IT Integration suggests itself to meet these challenges. However, it can also eliminate the benefits that SIT presents. To help organizations in this area of conflict, we are conducting a literature review including a systematic search and an analysis from a systemic viewpoint using path dependency and switching costs. Our resulting conceptual framework for SIT integration drawbacks classifies the drawbacks into three dimensions. The first dimension consists of switching costs that account for the financial, procedural, and emotional drawbacks and the drawbacks from a loss of SIT benefits. The second dimension includes organizational, technical, and level-spanning criteria. The third dimension classifies the drawbacks into the global level, the local level, and the interaction between them. We contribute to the scientific discussion by introducing a systemic viewpoint to the research on shadow IT. Practitioners can use the presented criteria to collect evidence to reach an IT integration decision.
ERP systems integrate a major part of all business processes and organizations include them in their IT service management. Besides these formal systems, there are additional systems that are rather stand-alone and not included in the IT management tasks. These so-called ‘shadow systems’ also support business processes but hinder a high enterprise integration. Shadow systems appear during their explicit detection or during software maintenance projects such as enhancements or release changes of enterprise systems. Organizations then have to decide if and to what extent they integrate the identified shadow systems into their ERP systems. For this decision, organizations have to compare the capabilities of each identified shadow system with their ERP systems. Based on multiple-case studies, we provide a dependency approach to enable their comparison. We derive categories for different stages of the dependency and base insights into integration possibilities on these stages. Our results show that 64% of the shadow systems in our case studies are related to ERP systems. This means that they share parts or all of their data and/or functionality with the ERP system. Our research contributes to the field of integration as well as to the discussion about shadow systems.
Die Beständigkeit von hochlegierten korrosions- und säurebeständigen Stählen wird primär durch den Chromgehalt bestimmt. Allerdings gibt es entlang der Wertschöpfungskette von der Stahlerschmelzung bis zum fertigen Produkt eine Vielzahl weiterer Einflussfaktoren. Dem Schleifen kommt hier eine besondere Bedeutung zu, da es je nach Wahl der Prozessparameter sowohl zu einer signifikanten Verschlechterung als auch zu einer Verbesserung der Korrosionsbeständigkeit führen kann. Im vorliegenden Beitrag wird aufgezeigt, dass die erzeugte Rauheit nur eine begrenzte Aussagekraft bietet. Vielmehr erhöhen lokale Mikrodefekte die Anfälligkeit gegen Lochfraß – je nach Ausprägung und Anzahl. Die Automatisierung für die Innenbearbeitung von Behältern im pharmazeutischen Apparatebau kann dabei zu einer signifikanten Verbesserung der Oberfläche und einem homogeneren Erscheinungsbild führen.
Der digitale Seilüberwacher
(2020)
AbstractSanctions encompass a wide set of policy instruments restricting cross‐border economic activities. In this paper, we study how different types of sanctions affect the export behavior of firms to the targeted countries. We combine Danish register data, including information on firm‐destination‐specific exports, with information on sanctions imposed by Denmark from the Global Sanctions Database. Our data allow us to study firms' export behavior in 62 sanctioned countries, amounting to a total of 453 country‐years with sanctions over the period 2000–2015. Methodologically, we apply a two‐stage estimation strategy to properly account for multilateral resistance terms. We find that, on average, sanctions lead to a significant reduction in firms' destination‐specific exports and a significant increase in firms' probability to exit the destination. Next, we study heterogeneity in the effects of sanctions across (i) sanction types and sanction packages, (ii) the objectives of sanctions, and (iii) countries subject to sanctions. Results confirm that the effects of sanctions on firms' export behavior vary considerably across these three dimensions.
„Am Einzelnen das Allgemeine lernen“ ist ein vor über 50 Jahren vorgeschlagenes, dem modernen Verständnis von Lernen angepasstes Vorgehen in der Physikausbildung. Allerdings hat sich dieses Konzept bis heute noch nicht durchgesetzt. Im vorliegenden Text beschreiben die beiden Autoren, wie die Umstellung der „Physikausbildung von Ingenieuren“ einer gesamten Hochschule von der Lehre von Inhalten auf eine Vermittlung von Physik-Methoden angegangen wurde und schließlich gelungen ist. Für Ihre Arbeiten erhielten sie den Ars legendi-Fakultätenpreis Physik 2014.
In modern fruit processing technology, non-destructive quality measuring techniques aresought for determining and controlling changes in the optical, structural, and chemical properties of theproducts. In this context, changes inside the product can be measured during processing. Especiallyfor industrial use, fast, precise, but robust methods are particularly important to obtain high-qualityproducts. In this work, a newly developed multi-spectral imaging system was implemented andadapted for drying processes. Further it was investigated if the system could be used to link changesin the surface spectral reflectance during mango drying with changes in moisture content andcontents of chemical components. This was achieved by recovering the spectral reflectance frommulti-spectral image data and comparing the spectral changes with changes of the total soluble solids(TSS), pH-value and the relative moisture contentxwbof the products. In a first step, the camera wasmodified to be used in drying, then the changes in the spectra and quality criteria during mangodrying were measured. For this, mango slices were dried at air temperatures of 40–80◦C and relativeair humidities of 5%–30%. Samples were analyzed and pictures were taken with the multi-spectralimaging system. The quality criteria were then predicted from spectral data. It could be shown thatthe newly developed multi-spectral imaging system can be used for quality control in fruit drying.There are strong indications as well, that it can be employed for the prediction of chemical qualitycriteria of mangoes during drying. This way, quality changes can be monitored inline during theprocess using only one single measuring device.
Energiequelle Seewasser
(2015)
Der Wandel des Einzelhandels
(2023)
Die Ursachen der existentiellen Bedrohung vieler Einzelhandelsunternehmen sind nicht nur auf die Nachwirkungen der Coronapandemie und den Ukraine-Krieg mit der daraus resultierenden Inflation und Kaufzurückhaltung zurückzuführen. Auch die Digitalisierung und die wachsende Onlinekonkurrenz sowie ein verändertes Einkaufs- und Konsumverhalten der Kund:innen setzt den Einzelhandel unter Druck. Dabei scheint besonders die junge Generation Z, die mit dem Internet, sozialen Medien und digitalen Anwendungen aufgewachsen ist, nicht mehr den traditionellen Konsummustern zu entsprechen, und erwartet eine Ausrichtung des Einzelhandels an ihre Bedürfnisse. Doch wie ticken junge Konsument:innen und wie unterscheiden sich ihre Erwartungen an den Handel von älteren Generationen? Im Beitrag werden Antworten auf diese Fragen gegeben.
Lidar sensors are widely used for environmental perception on autonomous robot vehicles (ARV). The field of view (FOV) of Lidar sensors can be reshaped by positioning plane mirrors in their vicinity. Mirror setups can especially improve the FOV for ground detection of ARVs with 2D-Lidar sensors. This paper presents an overview of several geometric designs and their strengths for certain vehicle types. Additionally, a new and easy-to-implement calibration procedure for setups of 2D-Lidar sensors with mirrors is presented to determine precise mirror orientations and positions, using a single flat calibration object with a pre-aligned simple fiducial marker. Measurement data from a prototype vehicle with a 2D-Lidar with a 2 m range using this new calibration procedure are presented. We show that the calibrated mirror orientations are accurate to less than 0.6° in this short range, which is a significant improvement over the orientation angles taken directly from the CAD. The accuracy of the point cloud data improved, and no significant decrease in distance noise was introduced. We deduced general guidelines for successful calibration setups using our method. In conclusion, a 2D-Lidar sensor and two plane mirrors calibrated with this method are a cost-effective and accurate way for robot engineers to improve the environmental perception of ARVs.
A growing share of modern trade policy instruments is shaped by non-tariff barriers (NTBs). Based on a structural gravity equation and the recently updated Global Trade Alert database, we empirically investigate the effect of NTBs on imports. Our analysis reveals that the implementation of NTBs reduces imports of affected products by up to 12%. Their trade dampening effect is thus comparable to that of trade defence instruments such as anti-dumping duties. It is smaller for exporters that have a free trade agreement with the importing country. Different types of NTBs affect trade to a different extent. Finally, we investigate the effect of behind-the-border measures, showing that they significantly lower the importer’s market access.
Wie gehen mittelständische Unternehmen mit internationaler Geschäftstätigkeit mit Compliance-Risiken um? Wie gelingt das Risikomanagement spezifischer Herausforderungen der Regelkonformität in Wachstumsländern, die aus Compliance-Gesichtspunkten als Hochrisikoländer eingestuft werden? Und was beschäftigt dabei Compliance-Officer im Mittelstand? Diesen Fragen widmete sich ein anwendungsorientiertes Forschungsprojekt am Konstanz Institut für Corporate Governance.
As interest in the investigation of possible sources and environmental sinks of technology-critical elements (TCEs) continues to grow, the demand for reliable background level information of these elements in environmental matrices increases. In this study, a time series of ten years of sediment samples from two different regions of the German North Sea were analyzed for their mass fractions of Ga, Ge, Nb, In, REEs, and Ta (grain size fraction < 20 µm). Possible regional differences were investigated in order to determine preliminary reference values for these regions. Throughout the investigated time period, only minor variations in the mass fractions were observed and both regions did not show significant differences. Calculated local enrichment factors ranging from 0.6 to 2.3 for all TCEs indicate no or little pollution in the investigated areas. Consequently, reference values were calculated using two different approaches (Median + 2 median absolute deviation (M2MAD) and Tukey inner fence (TIF)). Both approaches resulted in consistent threshold values for the respective regions ranging from 158 µg kg−1 for In to 114 mg kg−1 for Ce. As none of the threshold values exceed the observed natural variation of TCEs in marine and freshwater sediments, they may be considered baseline values of the German Bight for future studies.
Compliance meets CSR
(2023)
Was früher Gegenstand freiwilliger Selbstverpflichtung war, wird seit einiger Zeit zunehmend reguliert: die Wahrnehmung der unternehmensspezifischen Verantwortung gegenüber Umwelt und Gesellschaft, neudeutsch Corporate Social Responsibility (CSR). CSR und Compliance rücken damit näher zusammen. Vieles, was früher durch CSR-Abteilungen im besten Fall systematisch gemanagt wurde, ist nun gesetzlich vorgeschrieben und fällt damit in den Aufgabenbereich von Compliance. Liegt es da nicht nahe, die beiden Bereiche miteinander zu verschmelzen respektive CSR dem Bereich unterzuordnen, der seit den spektakulären Korruptions- und Bilanzfälschungsskandalen zu Beginn dieses Jahrtausends über die größere Management-Awareness verfügt?
Der vorliegende Beitrag versucht deutlich zu machen, wie das Verhältnis sachlich-fachlich einzuordnen ist und welche Schlussfolgerungen in der Praxis daraus gezogen werden könnten.
Unternehmensethik auf dem Vormarsch: ISO 26000 macht Ethik zur Norm globalen Wirtschaftshandelns
(2011)
Die konsensuell erarbeitete ISO 26000 ist ein Leitfaden zur Umsetzung von gesellschaftlicher Verantwortung. Sie sorgt nicht nur für ein klareres Verständnis des Beitrags, den alle Arten von Organisationen zur nachhaltigen Entwicklung der Gesellschaft leisten können, sondern führt die verschiedenen CSR-Themen zusammen, denen sich alle Organisationen, unabhängig von ihrem Zweck, ihrer Größe oder ihrem Standort heute gegenübersehen. Dabei integriert die ISO 26000 als Produkt eines einzigartigen, weltweiten Normungsprozesses bereits bestehende Normen und CSR-Standards zu einem international akzeptierten Leitfaden.
Der Aufsatz beleuchtet die Entstehungsgeschichte des Leitfadens und seine Inhalte, mit dessen Hilfe Organisationen das Ziel gesellschaftlicher Wohlfahrt verfolgen können und sollen.