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Long-Run Equilibrium Modeling of Alternative Emissions Allowance Allocation Systems in Electric Power Markets
A question in the design of carbon dioxide trading systems is how allowances are to be initially allocated: by auction, by giving away fixed amounts, or by allocating based on output, fuel, or other decisions. The latter system can bias investment, operations, and pricing decisions, and increase costs relative to other systems. A nonlinear complementarity model is used to investigate long-run equilibria that would result under alternative systems for power markets characterized by time varying demand and multiple generation technologies. Existence of equilibria is shown under mild conditions. Solutions show that allocating allowances to new capacity based on fuel use or generator type can distort generation mixes, invert the operating order of power plants, and inflate consumer costs. The distortions can be smaller for tighter CO2 restrictions, and are somewhat mitigated if there are also electricity capacity markets or minimum-run restrictions on coal plants
Behavior modelling and individual recognition of sonar transmitter for secure communication in UASNs
It is necessary to improve the safety of the underwater acoustic sensor networks (UASNs) since it is mostly used in the military industry. Specific emitter identification is the process of identifying different transmitters based on the radio frequency fingerprint extracted from the received signal. The sonar transmitter is a typical low-frequency radiation source and is an important part of the UASNs. Class D Power Amplifier, a typical non-linear amplifier, is usually used in sonar transmitters. The inherent nonlinearity of
power amplifiers provides fingerprint features that can be distinguished without transmitters for specific emitter recognition. Firstly, the non-linearity of the sonar transmitter is studied in depth, and the nonlinearity of the power amplifier is modeled and its non-linearity characteristics are analyzed. After obtaining the nonlinear model of an amplifier, a similar amplifier in practical application is obtained by changing its model parameters as the research object. The output signals are collected by giving the same input of different models, and then the output signals are extracted and classified. In this paper, the memory polynomial model is used to model the amplifier. The power spectrum features of the output signals are extracted as fingerprint features. Then the dimensionality of the high-dimensional features is reduced. Finally, the classifier is used to recognize the amplifier. The experimental results show that the individual sonar transmitter can be well identified by using the non-linear characteristics of the signal. By this way, this method can enhance the communication safety of UASNs
Development of an intelligent hypertext manual for the space shuttle hazardous gas detection system
A computer-based Integrated Knowledge System (IKS), the Intelligent Hypertext Manual (IHM), is being developed for the Space Shuttle Hazardous Gas Detection System (HGDS) at the Huntsville Operations Support Center (HOSC). The IHM stores all HGDS related knowledge and presents them in an interactive and intuitive manner. The IHM's purpose is to provide HGDS personnel with the capabilities of: enhancing the interpretation of real time data; recognizing and identifying possible faults in the Space Shuttle sub-system related to hazardous gas detections; locating applicable documentation related to procedures, constraints, and previous fault histories; and assisting in the training of personnel
Probing non-Abelian statistics of Majorana fermions in ultracold atomic superfluid
We propose an experiment to directly probe the non-Abelian statistics of
Majorana fermions by braiding them in an s-wave superfluid of ultracold atoms.
We show different orders of braiding operations give orthogonal output states
that can be distinguished through Raman spectroscopy. Realization of Majorana
bound states in an s-wave superfluid requires strong spin-orbital coupling and
a controllable Zeeman field in the perpendicular direction. We present a simple
laser configuration to generate the artificial spin-orbital coupling and the
required Zeeman field in the dark state subspace.Comment: 4 pages; Add detailed discussion of feasibility of the scheme;add
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EventMe: Location-Based Event Content Distribution through Human Centric Device-to-Device Communications
Location-based information dissemination has become increasingly popular in the recent years. Extensive research work has been done on the matching of interested parties to event information via publish/subscribe systems. However, the rich content types of such location-specific data, especially when the data are presented in multimedia form, requires efficient methods with low cost to transfer the content to the subscribers. In this paper, the potential of utilising human centric device-to-device (D2D) communications to disseminate location-based event content is investigated. The human centric D2D data dissemination process is formulated as a task assignment problem, which can be modelled as a Integer Quadratically Constrained Quadratic Programming (IQCQP) problem. Since the IQCQP problem is in general NP-hard, a sub- optimal polynomial framework named EventMe is proposed, which is able to compute a solution with guaranteed lower bounds on data distribution capacity in terms of throughput. Through extensive evaluation using several real world datasets, it has shown that EventMe is able to improve the network throughput by 100%-500% compared to baseline methods. A prototype is developed and shows that it is practical to implement EventMe on mobile devices by generating minimal control data overhead
Microstructure and Fe-vacancy ordering in the KFexSe2 superconducting system
Structural investigations by means of transmission electron microscopy (TEM)
on KFexSe2 with 1.5 \leq x \leq 1.8 have revealed a rich variety of
microstructure phenomena, the KFe1.5Se2 crystal often shows a superstructure
modulation along the [310] zone-axis direction, this superstructure can be well
interpreted by the Fe-vacancy order within the a-b plane. Increase of
Fe-concentration in the KFexSe2 materials could not only result in the
appearance of superconductivity but also yield clear alternations of
microstructure. Structural inhomogeneity, the complex superstructures and
defect structures in the superconducting KFe1.8Se2 sample have been
investigated based on the high-resolution TEM.Comment: 13 pages, 4 figure
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