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With regard to the angular momentum (AM) of light, we distinguish two different constituents: the spin AM referring to the polarization state and the orbital AM linked to the phase gradient of the electromagnetic wave [1-3]. Locally, these two dynamical quantities are described by the spin and orbital AM densities s and l. In the electric-magnetic-democracy or dual-symmetry representation [1-4], these...
There are different concepts of economic evaluation to show the role of trauma and injury in today’s health care. This chapter demonstrates that an economic evaluation is not limited to mortality or morbidity calculations.. Economic analyses evaluate medical costs in relation to health benefit. In all concepts costs are measured in monetary units and are divided in direct and indirect costs. The difficult...
Sufficient pain management is a prerequisite for enhanced patient recovery and for a reduction in postoperative morbidity and mortality.Pain assessment and documentation (‘fifth vital sign’) are fundamental prerequisites for adequate pain management.Opioids remain the fundamental group of analgesic drugs for the treatment of moderate-to-severe pain.Co-analgesics support the action of analgesics but...
We offer a translation into English of the original French version published in 1777 of Buffon’s Essai d’Arithmetique Morale. In this classic work, Buffon discusses degrees of certainty, probability, the moral value of money, the different evaluations of gains and of losses; moreover, he proposes repeated experiments to determine the moral value of a game. Our hope is that this remarkable work, which...
Bei Pentaerithrityltetranitrat handelt es sich um einen organischen Nitratester mit vasodilatativer Wirkung. Obwohl diese Substanz bereits seit den vierziger Jahren therapeutisch eingesetzt wird, wurden erste pharmakokinetische Untersuchungen erst in den sechziger Jahren durchgeführt. Ein Grund dafür liegt darin, dass sich trotz der scheinbar einfachen Struktur nur wenige der üblichen analytischen...
Introduction: The purpose of this meta-analysis was to examine whether staplers are a better technique for securing the appendiceal stump as compared to loops. Methods: Randomised controlled trials were searched for in various medical literature databases. Data on complication rates and other short-term results were pooled in random-effects meta-analyses with quantification of heterogeneity...
Recent research in the area of ubiquitous computing lead to innovative technologies for acquisition, storage and communication of real-world information, resulting in a multitude of so called ??smart items??. Prominent examples for that are RFID and wireless sensor nodes. Key to everaging the full power of these items is to embedd them into a system architecture. In this paper we present such an architecture...
In spite of continuous improvements at running production systems, down times have to be reduced further. The challenge is to find means to implement changes online which denotes avoid stopping and restarting the system. As changes on running systems are difficult to handle and may result in lost states a solution is to replicate the running system, modify it in parallel and reintegrate the changes...
Traffic models are very important for the performance evaluation of communications systems and decisive for the result quality. The usage of off-the-shelf devices in control networks permits also to use detailed, reusable device traffic models in performance prediction of the network design. However, this requires a high diversification of the device traffic models to support the high number of device...
As shown in previous work, the duty cycle can be adapted to the traffic of the applications in higher OSI layers. In this paper, an analysis approach is shown to determine the static and dynamic behavior of the previously proposed adaptation algorithm. Therefore, we use two different mathematical tool sets: Markov chains and difference equations. Comparisons with simulations results show that the...
Energy is a scarce resource in wireless sensor networks. Usually, during the deployment phase an appropriate duty cycle has to be found to adjust the trade-off between energy consumption and transmission delay. In this paper an adaptation algorithm for the duty cycle adjustment during runtime of the sensor network is proposed. Thereby, the traffic originating from sensor nodes is monitored in the...
The new IEEE 802.15.4 standard enables deployment of low-rate low-power personal area networks. It provides a mechanism for adaptation of the protocols duty cycle during runtime. In this paper we propose BOAA, a new algorithm for beacon order adaptation in IEEE 802.15.4 star-topology networks. By observing the communication frequency, the coordinator in such a network determines the required duty...
Network performance engineering can verify the design and dimensioning of large size control networks like CSMA based building automation networks. It combines performance analysis with diagnosis methods to evaluate the network utilization and detect design errors before installation and can therewith save the expenses of overdimensioning and redesign. This paper will develop a diagnosis model based...
Developing building automation systems requires careful planning of the applications and the network topology. Editing a model with up to 32,000 nodes manually is very time-consuming. In this paper, an automated approach for modeling LonWorks networks is presented. As a basis the existing LNS network operating system which is suited for integration and management purposes is used. It contains all...
Traffic models play a decisive part in the performance evaluation and design of communications systems. However, the growing diversification of devices in large networks asks for automated generated traffic models. In this paper, we present a generic device model which is suited for automated generation in the domain of building automation. The traffic is deduced successive for common devices from...
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