Semantics of programming languages : a tool-oriented approach

By paying more attention to semantics-based tool generation, programming language semantics can significantly increase its impact. Ultimately, this may lead to ``Language Design Assistants'' incorporating substantial amounts of semantic knowledge

Semantics of programming languages : a tool-oriented approach

By paying more attention to semantics-based tool generation, programming language semantics can significantly increase its impact. Ultimately, this may lead to ``Language Design Assistants\'\' incorporating substantial amounts of semantic knowledge

Semantics of programming languages : a tool-oriented approach

By paying more attention to semantics-based tool generation, programming language semantics can significantly increase its impact. Ultimately, this may lead to ``Language Design Assistants'' incorporating substantial amounts of semantic knowledge

An overview of recent research results and future research avenues using simulation studies in project management

This paper gives an overview of three simulation studies in dynamic project scheduling integrating baseline scheduling with risk analysis and project control. This integration is known in the literature as dynamic scheduling. An integrated project control method is presented using a project control simulation approach that combines the three topics into a single decision support system. The method makes use of Monte Carlo simulations and connects schedule risk analysis (SRA) with earned value management (EVM). A corrective action mechanism is added to the simulation model to measure the efficiency of two alternative project control methods. At the end of the paper, a summary of recent and state-of-the-art results is given, and directions for future research based on a new research study are presented

Open Source Test Bed and Test Case Development for Power System Research

Replication and reproducability are the cornerstones of the scientific method. Readers of published works must be able to rerun simulations and replicate results, given the information provided in the publication. The results of a published study must also be reproducible using an independent implementation of a method. Open source tools and open source test systems are critical in creating environments where this is possible. This thesis contributes to open source test system and test bed development in the support of research and engineering for power system optimization, simulation and modeling. It does this in two major ways, described below. This thesis develops an open-source 8-Zone Test System for teaching, training, and research purposes that is based on ISO New England structural attributes and data. The test system models an ISO-managed wholesale power market populated by a mix of generating companies and load-serving entities that operates through time over an 8-zone transmission grid. The modular extensible architecture of the test system permits a wide range of sensitivity studies to be conducted. This thesis also further develops AMES with new features in the form of a release as AMES (V4.0). A core component of AMES has been modularized into a separate package called Power System Simulation Toolbox (PSST). PSST includes a power flow, Optimal Power Flow (OPF), wholesale market operation including a Security Constrained Unit Commitment (SCUC) and a Security Constrained Economic Dispatch (SCED). The ease of rapid prototyping and tools provided by this toolkit make this an ideal candidate for power system analysis. Test cases employing these few features are demonstrated to show the value of these capabilities. Additionally, the new features of AMES (V4.0) are thoroughly tested and their performance was characterized

Ergebnisse und zugrundeliegende Mechanismen der Hypoglossusnerv-Stimulation bei Patienten mit obstruktiver Schlafapnoe

Since 2001, hypoglossal nerve stimulation (HNS) has been used worldwide to treat adult patients with obstructive sleep apnea (OSA). However, the long-term outcomes following HNS and the underlying mechanisms have not been comprehensively investigated, and no studies have reported a persistent development course of a severe complication treatment-emergent central sleep apnea (TECSA) following HNS. Moreover, the prognostic indicators associated with successful HNS therapy to treat OSA and the occurrence of TECSA remain controversial. Therefore, this retrospective study aimed to evaluate the long-term outcomes of HNS and explore the prognostic indicators and underlying mechanisms to improve clinical effectiveness and avoid complications following HNS. Twenty-seven patients who underwent HNS implantation since 2016 were included in this study. Demographic, pre- and postoperative sleep study characteristics and device settings data were collected to evaluate the effects of HNS during evaluation. We compared the difference between the HNS success (n=13) and failure groups (n=14), and postoperative elevated central sleep apnea (n=3) and non-elevated CSA groups (n=24), respectively, and identified possible factors associated with the successful response to HNS and postoperative elevated CSA. Based on the persistent developmental course and phenotype of TECSA during evaluation, we hypothesized that an appropriate stimulation amplitude would resolve the development of TECSA and performed a titration study to help explore the underlying mechanisms. During 3 years of evaluation after device activation, HNS reduced OSA events and improved oxygenation with a success rate of 50%. An elevated preoperative Epworth sleepiness scale (ESS) score was associated with treatment failure, while other baseline demographic characteristics and polysomnography data could not predict the effects of HNS. Regarding complications following HNS, three patients had elevated CSA (CAI ≥ 5), which was associated with an increased preoperative ESS and mixed sleep apnea index (MAI). The persistent course of TECSA as well as a strong negative correlation between CSA and OSA revealed that the underlying mechanisms might be multiple combinations of the upper airway effect and high loop gain. In conclusion, HNS is an effective and promising treatment method for patients with OSA who cannot tolerate continuous positive airway pressure therapy (CPAP). Precise patient selection, individual titration configuration and scheduled follow-ups could help improve the effectiveness and reduce complications following HNS. In addition, a better understanding of the subtypes and endotypes of OSA should be translated into clinical use in the future to identify more predictive factors.Seit 2001 wird Hypoglossusnerv-Stimulation (HNS) weltweit zur Behandlung erwachsener Patienten mit obstruktiver Schlafapnoe (OSA) eingesetzt. Die Langzeitergebnisse nach HNS und die zugrundeliegenden Mechanismen sind jedoch nicht umfassend untersucht worden, und in keiner Studie wurde über einen anhaltenden Entwicklungsverlauf -Treatment-emergent central sleep apnea (TECSA)-nach HNS berichtet. Darüber hinaus sind die prognostischen Indikatoren für eine erfolgreiche HNS-Therapie zur Behandlung von OSA und das Auftreten von TECSA nach wie vor umstritten. Ziel dieser Studie war es daher, die Langzeitergebnisse der HNS zu prüfen und die prognostischen Indikatoren sowie die zugrunde liegenden Mechanismen zu untersuchen, um die klinische Wirksamkeit zu verbessern und Komplikationen nach der HNS zu vermeiden. In diese Studie wurden 27 Patienten aufgenommen, die sich seit 2016 einer HNS-Implantation unterzogen. Präoperative demografische Merkmale, Merkmale der Schlafstudie von Polysomnografie /Polygrafie für zu Hause vor und nach der Implantation und Gerätekonfiguration wurden gesammelt, um die Wirkung von HNS während der Auswertung zu bewerten. Aufgrund des anhaltenden Entwicklungsverlaufs und Phänotyps von TECSA während der Auswertung stellten wir die Hypothese auf, dass eine geeignete Stimulationsamplitude die Entwicklung von TECSA auflösen würde, und führten eine Titrationsstudie durch, um die zugrundeliegenden Mechanismen zu erforschen. Während der dreijährigen Auswertung nach der Aktivierung des Geräts konnte HNS die OSAEreignisse reduzieren und die Oxygenierung mit einer Erfolgsrate von 50% verbessern. Ein erhöhter präoperativer Epworth-Sleepiness-Scale (ESS) wert war mit einem Behandlungsversagen assoziiert, während andere Präoperative demografische Merkmale und Merkmale der Polysomnographie die Wirkung von HNS nicht vorhersagen konnten. Was die Komplikationen nach der HNS betrifft, so wiesen drei Patienten einen erhöhten CSA (CAI ≥ 5) auf, der mit einem erhöhten präoperativen ESS wert und einem gemischten Schlafapnoe-Index (MAI) verbunden war. Der anhaltende Verlauf von TECSA und eine starke negative Korrelation zwischen CSA und OSA zeigten, dass die zugrundeliegenden Mechanismen mehrere Kombinationen aus dem Effekt der oberen Atemwege und einer hohen Schleifenverstärkung sein könnten. Zusammenfassend lässt sich sagen, dass HNS eine wirksame und vielversprechende Behandlungsmethode für Patienten mit OSA ist, die eine kontinuierliche positive Atemwegsdrucktherapie (CPAP) nicht vertragen. Eine genaue Patientenauswahl, eine individuelle Titrationskonfiguration und geplante Nachuntersuchungen könnten dazu beitragen, die Wirksamkeit zu verbessern und Komplikationen nach der HNS zu verringern. Darüber hinaus sollte ein besseres Verständnis der Subtypen und Endtypen der OSA in Zukunft in die klinische Praxis umgesetzt werden, um weitere prädiktive Faktoren zu ermitteln

Social, environmental and economic impacts of alternative energy and fuel supply chains

Energy supply nowadays, being a vital element of a country’s development, has to independently meet diverse, sustainability criteria, be it economic, environmental and social. The main goal of the present research work is to present a methodological framework for the evaluation of alternative energy and fuel Supply Chains (SCs), consisting of a broad topology (representation) suggested, encompassing all the well-known energy and fuel SCs, under a unified scheme, a set of performance measures and indices as well as mathematical model development, formulated as Multi-objective Linear Programming with the extension of incorporating binary decisions as well (Multi-objective Mixed Integer-Linear programming). Basic characteristics of the current modelling approach include the adaptability of the model to be applied at different levels of energy SCs decisions, under different time frames and for multiple stakeholders. Model evaluation is carried for a set of Greek islands, located in the Aegean Archipelagos, examining both the existing energy supply options as well future, more sustainable Energy Supply Chains (ESCs) configurations. Results of the specific research work reveal the social and environmental costs which are underestimated under the traditional energy supply options' evaluation, as well as the benefits that may be produced from renewable energy based applications in terms of social security and employment

Wide-field Mueller matrix polarimetry for spectral characterization of basic biological tissues: muscle, fat, connective tissue, and skin

This study investigates the polarimetric properties of skin, skeletal muscle, connective tissue, and fat using Mueller matrix imaging. It aims to compare the polarimetric characteristics of these tissues and explore how they evolve with wavelength. Additionally, the temporal evolution of certain tissues during meat aging is studied, providing insights into the dynamic behavior of polarimetric properties over time. The research employs back-scattering configuration and the differential decomposition analysis method of Mueller matrix images. Both in-vivo and ex-vivo experiments were conducted using a consistent instrument setup to ensure reliable analysis. The results reveal wavelength-dependent variations in tissue properties, including an increase in depolarization with wavelength. Significant differences in the polarimetric characteristics of meat tissues, particularly for skeletal muscle, are observed. Over a 24-h period, intensity, diattenuation, and retardation experience alterations, being the decreased retardation in skeletal muscle and the increased retardation in fat the most notable ones