Managing Uncertain Complex Events in Web of Things Applications

A critical issue in the Web of Things (WoT) is the need to process and analyze the interactions of Web-interconnected real-world objects. Complex Event Processing (CEP) is a powerful technology for analyzing streams of information about real-time distributed events, coming from different sources, and for extracting conclusions from them. However, in many situations these events are not free from uncertainty, due to either unreliable data sources and networks, measurement uncertainty, or to the inability to determine whether an event has actually happened or not. This short research paper discusses how CEP systems can incorporate different kinds of uncertainty, both in the events and in the rules. A case study is used to validate the proposal, and we discuss the benefits and limitations of this CEP extension.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Linear Scaling Solution of the Coulomb problem using wavelets

The Coulomb problem for continuous charge distributions is a central problem in physics. Powerful methods, that scale linearly with system size and that allow us to use different resolutions in different regions of space are therefore highly desirable. Using wavelet based Multi Resolution Analysis we derive for the first time a method which has these properties. The power and accuracy of the method is illustrated by applying it to the calculation of of the electrostatic potential of a full three-dimensional all-electron Uranium dimer

How can a 22-pole ion trap exhibit 10 local minima in the effective potential?

The column density distribution of trapped OH$^-$ ions in a 22-pole ion trap is measured for different trap parameters. The density is obtained from position-dependent photodetachment rate measurements. Overall, agreement is found with the effective potential of an ideal 22-pole. However, in addition we observe 10 distinct minima in the trapping potential, which indicate a breaking of the 22-fold symmetry. Numerical simulations show that a displacement of a subset of the radiofrequency electrodes can serve as an explanation for this symmetry breaking

Fast multipole networks

Two prerequisites for robotic multiagent systems are mobility and communication. Fast multipole networks (FMNs) enable both ends within a unified framework. FMNs can be organized very efficiently in a distributed way from local information and are ideally suited for motion planning using artificial potentials. We compare FMNs to conventional communication topologies, and find that FMNs offer competitive communication performance (including higher network efficiency per edge at marginal energy cost) in addition to advantages for mobility

High Performance Algorithms for Counting Collisions and Pairwise Interactions

The problem of counting collisions or interactions is common in areas as computer graphics and scientific simulations. Since it is a major bottleneck in applications of these areas, a lot of research has been carried out on such subject, mainly focused on techniques that allow calculations to be performed within pruned sets of objects. This paper focuses on how interaction calculation (such as collisions) within these sets can be done more efficiently than existing approaches. Two algorithms are proposed: a sequential algorithm that has linear complexity at the cost of high memory usage; and a parallel algorithm, mathematically proved to be correct, that manages to use GPU resources more efficiently than existing approaches. The proposed and existing algorithms were implemented, and experiments show a speedup of 21.7 for the sequential algorithm (on small problem size), and 1.12 for the parallel proposal (large problem size). By improving interaction calculation, this work contributes to research areas that promote interconnection in the modern world, such as computer graphics and robotics.Comment: Accepted in ICCS 2019 and published in Springer's LNCS series. Supplementary content at https://mjsaldanha.com/articles/1-hpc-ssp

Two Modes of Magnetization Switching in a Simulated Iron Nanopillar in an Obliquely Oriented Field

Finite-temperature micromagnetics simulations are employed to study the magnetization-switching dynamics driven by a field applied at an angle to the long axis of an iron nanopillar. A bi-modal distribution in the switching times is observed, and evidence for two competing modes of magnetization-switching dynamics is presented. For the conditions studied here, temperature $T = 20$ K and the reversal field 3160 Oe at an angle of 75$^\circ$ to the long axis, approximately 70% of the switches involve unstable decay (no free-energy barrier) and 30% involve metastable decay (a free-energy barrier is crossed). The latter are indistinguishable from switches which are constrained to start at a metastable free-energy minimum. Competition between unstable and metastable decay could greatly complicate applications involving magnetization switches near the coercive field.Comment: 19 pages, 7 figure

Norbin ablation results in defective adult hippocampal neurogenesis and depressive-like behavior in mice

Adult neurogenesis in the hippocampus subgranular zone is associated with the etiology and treatment efficiency of depression. Factors that affect adult hippocampal neurogenesis have been shown to contribute to the neuropathology of depression. Glutamate, the major excitatory neurotransmitter, plays a critical role in different aspects of neurogenesis. Of the eight metabotropic glutamate receptors (mGluRs), mGluR5 is the most highly expressed in neural stem cells. We previously identified Norbin as a positive regulator of mGluR5 and showed that its expression promotes neurite outgrowth. In this study, we investigated the role of Norbin in adult neurogenesis and depressive-like behaviors using Norbin-deficient mice. We found that Norbin deletion significantly reduced hippocampal neurogenesis; specifically, the loss of Norbin impaired the proliferation and maturation of newborn neurons without affecting cell-fate specification of neural stem cells/neural progenitor cells (NSCs/NPCs). Norbin is highly expressed in the granular neurons in the dentate gyrus of the hippocampus, but it is undetectable in NSCs/NPCs or immature neurons, suggesting that the effect of Norbin on neurogenesis is likely caused by a nonautonomous niche effect. In support of this hypothesis, we found that the expression of a cell-cell contact gene, Desmoplakin, is greatly reduced in Norbin-deletion mice. Moreover, Norbin-KO mice show an increased immobility in the forced-swim test and the tail-suspension test and reduced sucrose preference compared with wild-type controls. Taken together, these results show that Norbin is a regulator of adult hippocampal neurogenesis and that its deletion causes depressive-like behaviors

Immunocytochemical localization of the neuron-specific form of the c-src gene product, pp60c-src(+), in rat brain

Neurons express high levels of a variant form of the c-src gene product, denoted pp60c-src(+), which contains a 6 amino acid insert in the amino-terminal half of the c-src protein. We have determined the localization of pp60c-src(+) in neurons using an affinity-purified anti-peptide antibody, referred to as affi-SB12, that exclusively recognizes this neuron-specific form of the c-src gene product. Using affi-SB12, we examined the distribution of pp60c-src(+) by immunoperoxidase staining of sections through adult rat brains, pp60c-src(+) was widely distributed in rat brain and appeared to be differentially expressed in subpopulations of neurons. The majority of immunoreactive neurons was found in the mesencephalon, cerebellum, pons, and medulla. Telencephalic structures that contained substantial populations of pp60c-src(+)-immunoreactive neurons included layer V of the cerebral cortex and the ventral pallidum. Within individual neurons, pp60c-src(+) immunoreactivity was localized to the cell soma and dendritic processes, while labeling of axons and nerve terminals (puncta) was not as readily detected. Dense accumulations of immunoreactive axons were rare, being most prominent in portions of the inferior and superior olive, and in the spinal trigeminal nucleus. While the regional distribution of pp60c-src(+) immunoreactivity does not correlate with any specific neuronal cell type or first messenger system, this unique pattern of expression of pp60c-src(+) suggests the existence of a previously uncharacterized functional organization within the brain. Furthermore, the localization of this neuron-specific tyrosine kinase in functionally important areas of the nerve cell, namely, dendritic processes, axons, and nerve terminals, suggests that pp60c-src(+) may regulate pleiotropic functions in specific classes of neurons in the adult central nervous system

Multi-Layer Cyber-Physical Security and Resilience for Smart Grid

The smart grid is a large-scale complex system that integrates communication technologies with the physical layer operation of the energy systems. Security and resilience mechanisms by design are important to provide guarantee operations for the system. This chapter provides a layered perspective of the smart grid security and discusses game and decision theory as a tool to model the interactions among system components and the interaction between attackers and the system. We discuss game-theoretic applications and challenges in the design of cross-layer robust and resilient controller, secure network routing protocol at the data communication and networking layers, and the challenges of the information security at the management layer of the grid. The chapter will discuss the future directions of using game-theoretic tools in addressing multi-layer security issues in the smart grid.Comment: 16 page