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We propose to measure, on a bunch-to-bunch basis, the beam energy at the International Linear e+e- Collider by recording synchrotron radiation (SR) light emitted in the magnets of an energy spectrometer based on beam position monitors. Measuring the width of the horizontal SR fan permits to determine the relative beam energy with a precision better than 10-4. There are two different measuring schemes possible. The first one is based on edge measurements of the direct SR fan, while the second option includes mirrors to deflect soft SR light to detectors located sufficiently off the beamline. Three possibilities for high-spatial resolution detectors are considered: a standard silicon strip detector, a novel-type Si detector and a gas amplification detector, both with exceptional position resolution. The main issue of the first scheme is the high radiation dose expected in the direct SR fan. If mirrors are used this dose is strongly reduced and allows application of any of the three detectors proposed.  相似文献   
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Next-generation military and civilian communication systems will require technologies capable of handling data/ audio, and video simultaneously while supporting multiple RF systems operating in several different frequency bands from the MHz to the GHz range [1]. RF microelectromechani-cal/nanoelectromechanical (MEMS/NEMS) devices, such as resonators and switches, are attractive to industry as they offer a means by which performance can be greatly improved for wireless applications while at the same time potentially reducing overall size and weight as well as manufacturing costs.  相似文献   
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E-procurement and supplier-relationship management systems have helped to substantially advance process execution in supply management. However, current supply network systems still face challenges of high data integration efforts, as well as the decoupling of structured data and processes from the growing amount of digitalized unstructured interactions of supply management professionals. Inspired by the room for improvement posed by this challenges, our research proposes a design for a supply network artifact in supplier qualification that addresses these problems by enabling holistic integration of data, processes, and people. The artifact is developed following an action design research approach. Building on a set of meta-requirements derived from literature and practice explorations, we conceptualize two design principles and derive corresponding design decisions that have been implemented in an software artifact. Finally, we formulate testable hypotheses and evaluate the artifact and its design in the context of supplier qualification. Our results show that the proposed design reduces mental effort of supply management professionals and significantly increases efficiency when performing typical supply network tasks such as supplier qualification.  相似文献   
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We used certain physiologic maneuvers to perturb the autonomic nervous system (ANS) in an attempt to detect a link between the ANS and pain. In the unperturbed state, we found no difference in the electrodermal response among normal controls, preoperative patients (increased stress without pain) and postoperative patients (increased stress and pain). The electrodermal response elicited by autonomic maneuvers was significantly attenuated in postoperative patients but not in preoperative patients or in normal control subjects.  相似文献   
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