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901.
We consider a technique for high-resolution image upconversion of thermal light. Experimentally, we demonstrate cw upconversion with a resolution of more than 200 × 1000 pixels of thermally illuminated objects. This is the first demonstration (to our knowledge) of high-resolution cw image upconversion. The upconversion method promises an alternative route to high-quantum-efficiency all-optical imaging in the mid-IR wavelength region and beyond using standard CCD cameras. A particular advantage of CCD cameras compared to state-of-the-art thermal cameras is the possibility to tailor and tune the spectral response leading to functional spectral imaging. 相似文献
902.
Tom Arne Pedersen 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(2):153-173
The main motivation for writing this article is to develop a model library for an All-Electric Ship that gives an opportunity to simulate both existing and new machinery systems without having to remodel the entire system each time. The model library should support the process of modelling and reuse, while also emphasizing openness to brace the modeller during the development and refinement phase. The bond graph approach is good when it comes to the physical modelling of systems and is a good tool for combining different energy domains to better help in understanding the system. In addition, a bond graph is a powerful method to find dependencies between various components. Using a causal analysis, any problems in the model, for example, algebraic constrains or dependent system variables, will be detected, and the necessary remodelling may be performed to handle such problems. The bond graph approach is therefore used when developing the component library. The component library consists of selected power producers such as diesel and gas engines, fuel cell and synchronous generator and power consumers such as asynchronous motor with a voltage source converter in addition to a generic load used for hotel and auxiliary loads. The library also consists of a ship model and propeller models. 相似文献
903.
Henrik L. Pedersen 《Journal of Computational and Applied Mathematics》2009,233(3):808-814
We show that there exist indeterminate Stieltjes moment problems with prescribed common logarithmic order and type. 相似文献
904.
A. E. Hansen S. Pedersen A. Kristensen C. B. Srensen P. E. Lindelof 《Physica E: Low-dimensional Systems and Nanostructures》2000,7(3-4)
We have investigated the Aharonov–Bohm effect in mesoscopic semiconductor GaAs/GaA1As rings in low magnetic fields. The oscillatory magnetoconductance of these systems is systematically studied as a function of electron density. We observe phase shifts of π in the magnetoconductance oscillations, and halving of the fundamental h/e period, as the density is varied. Theoretically, we find agreement with the experiment, by introducing an asymmetry between the two arms of the ring. 相似文献
905.
Horacio Arló-Costa Arthur Paul Pedersen 《International Journal of Approximate Reasoning》2012,53(3):293-315
This paper considers varieties of probabilism capable of distilling paradox-free qualitative doxastic notions (e.g., full belief, expectation, and plain belief) from a notion of probability taken as a primitive. We show that core systems, collections of nested propositions expressible in the underlying algebra, can play a crucial role in these derivations. We demonstrate how the notion of a probability core can be naturally generalized to high probability, giving rise to what we call a high probability core, a notion that when formulated in terms of classical monadic probability coincides with the notion of stability proposed by Hannes Leitgeb [32]. Our work continues by one of us in collaboration with Rohit Parikh [7]. In turn, the latter work was inspired by the seminal work of Bas van Fraassen [46]. We argue that the adoption of dyadic probability as a primitive (as articulated by van Fraassen [46]) admits a smoother connection with the standard theory of probability cores as well as a better model in which to situate doxastic notions like full belief. We also illustrate how the basic structure underlying a system of cores naturally leads to alternative probabilistic acceptance rules, like the so-called ratio rule initially proposed by Isaac Levi [34].Core systems in their various guises are ubiquitous in many areas of formal epistemology (e.g., belief revision, the semantics of conditionals, modal logic, etc.). We argue that core systems can also play a natural and important role in Bayesian epistemology and decision theory. In fact, the final part of the article shows that probabilistic core systems are naturally derivable from basic decision-theoretic axioms which incorporate only qualitative aspects of core systems; that the qualitative aspects of core systems alone can be naturally integrated in the articulation of coherence of primitive conditional probability; and that the guiding idea behind the primary qualitative features of a core system gives rise to the formulation of lexicographic decision rules. 相似文献
906.
Erik B. Pedersen Kim L. Dueholm Ali El-emam Thomas Kofoed Abdelmoneim A.-M. El-Torgoman Mohammed S. Motawia 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):465-466
Abstract 3′-Alkylthio-2′-,3′-dideoxy nucleosides and D4T are synthesized. An attempt of synthesizing a hybrid between AZT and HEPT is presented. 相似文献
907.
908.
909.
N. C. R. Holme L. Nikolova T. B. Norris S. Hvilsted M. Pedersen R. H. Berg P. H. Rasmussen P. S. Ramanujam 《Macromolecular Symposia》1999,137(1):83-103
Azobenzenes can serve as model compounds for the study of transcis isomerization in more complex molecules. We have performed time-resolved spectroscopy in solutions containing free azobenzene chromophores and diols with a view to obtaining the energy levels and lifetimes of the excited states. A transition route based on experimental results for the theoretically calculated energy level scheme is proposed. Physical observations of surface relief in thin films of azobenzene polymers when irradiated with polarized light are reported. These include two beam polarization holographic observations and single beam transmission measurements through a mask, followed by atomic force microscope and profiler investigations. It is concluded that none of the prevalent theories can explain all the observed facts. 相似文献