Multi-instance graphical transfer clustering for traffic data learning

© 2016 IEEE. In order to better model complex real-world data and to develop robust features that capture relevant information, we usually employ unsupervised feature learning to learn a layer of features representations from unlabeled data. However, developing domain-specific features for each task is expensive, time-consuming and requires expertise of the data. In this paper, we introduce multi-instance clustering and graphical learning to unsupervised transfer learning. For a better clustering efficient, we proposed a set of algorithms on the application of traffic data learning, instance feature representation, distance calculation of multi-instance clustering, multi-instance graphical cluster initialisation, multi-instance multi-cluster update, and graphical multi-instance transfer clustering (GMITC). In the end of this paper, we examine the proposed algorithms on the Eastwest datasets by couples of baselines. The experiment results indicate that our proposed algorithms can get higher clustering accuracy and much higher programming speed

Partitioning Method of Virtual Microgrid Based on Electrical Coupling Strength

© 2019 Automation of Electric Power Systems Press. With the fast development in the research of smart grid and Energy Internet, more and more distributed renewable energy and energy storage devices are connected into distribution networks, intelligent development of distribution network has become an inevitable trend. It is a big challenge for large-scale conventional distribution networks to be consistent with the requirements of free, equal and flexible interaction. Virtual microgrids with high internal convergence are proposed based on electrical coupling strength, which is partitioned from conventional power distribution networks. Furthermore, an implementation framework of virtual microgrids based on extended cyber, physical and socioeconomic is put forward, three-stage research problems of boundary division, resource optimization deployment and collaborative capability management are introduced. According to the first problem, by defining the electrical coupling strength, the classical Newman fast partitioning algorithm is upgraded in complicated network to realize the automatic optimization of boundary in virtual microgrids. Through case studies, the proposed algorithm is verified to be reasonable and efficient

Partitioning Method of Virtual Microgrid Based on Electrical Coupling Strength

© 2019 Automation of Electric Power Systems Press. With the fast development in the research of smart grid and Energy Internet, more and more distributed renewable energy and energy storage devices are connected into distribution networks, intelligent development of distribution network has become an inevitable trend. It is a big challenge for large-scale conventional distribution networks to be consistent with the requirements of free, equal and flexible interaction. Virtual microgrids with high internal convergence are proposed based on electrical coupling strength, which is partitioned from conventional power distribution networks. Furthermore, an implementation framework of virtual microgrids based on extended cyber, physical and socioeconomic is put forward, three-stage research problems of boundary division, resource optimization deployment and collaborative capability management are introduced. According to the first problem, by defining the electrical coupling strength, the classical Newman fast partitioning algorithm is upgraded in complicated network to realize the automatic optimization of boundary in virtual microgrids. Through case studies, the proposed algorithm is verified to be reasonable and efficient

Extending the first-order post-Newtonian scheme in multiple systems to the second-order contributions to light propagation

In this paper, we extend the first-order post-Newtonian scheme in multiple systems presented by Damour-Soffel-Xu to the second-order contribution to light propagation without changing the virtueof the scheme on the linear partial differential equations of the potential and vector potential. The spatial components of the metric are extended to second order level both in a global coordinates ($q_{ij}/ c^4$) and a local coordinates ($Q_{ab}/ c^4$). The equations of $q_{ij}$ (or $Q_{ab}$) are obtained from the field equations.The relationship between $q_{ij}$ and $Q_{ab}$ are presented in this paper also. In special case of the solar system (isotropic condition is applied ($q_{ij} = \delta_{ij} q$)), we obtain the solution of $q$. Finally, a further extension of the second-order contributions in the parametrized post-Newtonian formalism is discussed.Comment: Latex2e; 6 pages PS fil

Chandra Observations of MRK 273: Unveiling the Central AGN and the Extended Hot Gas Halo

We report X-ray observations of the field containing the ultraluminous IRAS galaxy Mrk~273 Using the ACIS-S3 instrument on board Chandra. The high resolution X-ray image, for the first time, reveals a compact hard X-ray nucleus in Mrk~273. Its X-ray energy distribution is well described by a heavily obscured power-law spectrum plus a narrow \Feka emission line at 6.4 keV. The neutral hydrogen column density is about 4\times10^{23}\cm^{-2}, implying an absorption -corrected X-ray luminosity (0.1--10 keV) for the nucleus of \Lx\approx 6.5\times 10^{43} \ergs. There are also bright soft X-ray clumps and diffuse soft X-ray emissions surrounding the central hard X-ray nucleus within the 10\arcsec of the nuclear region. Its spectrum can be fitted by a MEKAL thermal model with temperature of about 0.8 keV and high metallicity ($Z\sim 1.5Z_\odot$) plus emission lines from $\alpha$ elements and ions. Further outside the central region, the Chandra observations reveal a very extended hot gas halo with a projected diameter of about 108 \kpc\times 68 \kpc and soft X-ray luminosity of \Lx\approx 1.9\times 10^{41} \ergs. The temperature of the hot gas is about 0.62 keV with a low metallicity ($Z \sim 0.1 Z_\odot$). We discuss the nature of the AGN in Mrk~273 and the implications of our results on the origin of X-ray halos in elliptical galaxies. We also discuss the properties of Mrk~273x, a background AGN in the Mrk~273 field. The AGN has an X-ray luminosity of \Lx \approx 2.43\times 10^{44}\ergs in the 0.5-10 keV band. Its X-ray properties resemble those of Seyfert 1 galaxies while its optical properties are similar to Seyfert 2 galaxies. Such mixed classifications may be a challenge for the unification scheme of AGNs.Comment: 23 pages, 11 figures. ApJ accepted, minor revised versio

Sex-specific fundamental and formant frequency patterns in a cross-sectional study

An extensive developmental acoustic study of the speech patterns of children and adults was reported by Lee and colleagues [Lee et al., J. Acoust. Soc. Am. 105, 1455-1468 (1999)]. This paper presents a reexamination of selected fundamental frequency and formant frequency data presented in their report for 10 monophthongs by investigating sex-specific and developmental patterns using two different approaches. The first of these includes the investigation of age- and sex-specific formant frequency patterns in the monophthongs. The second, the investigation of fundamental frequency and formant frequency data using the critical band rate (bark) scale and a number of acoustic-phonetic dimensions of the monophthongs from an age- and sex-specific perspective. These acoustic-phonetic dimensions include: vowel spaces and distances from speaker centroids; frequency differences between the formant frequencies of males and females; vowel openness/closeness and frontness/backness; the degree of vocal effort; and formant frequency ranges. Both approaches reveal both age- and sex-specific development patterns which also appear to be dependent on whether vowels are peripheral or non-peripheral. The developmental emergence of these sex-specific differences are discussed with reference to anatomical, physiological, sociophonetic and culturally determined factors. Some directions for further investigation into the age-linked sex differences in speech across the lifespan are also proposed

Optical Monitoring of BL Lacertae Object OJ 287: a 40-Day Period?

We present the results of our optical monitoring of the BL Lacertae object OJ 287 during the first half of 2005. The source did not show large-amplitude variations during this period and was in a relatively quiescent state. A possible period of 40 days was derived from its light curves in three BATC wavebands. A bluer-when-brighter chromatism was discovered, which is different from the extremely stable color during the outburst in 1994--96. The different color behaviors imply different variation mechanisms in the two states. We then re-visited the optical data on OJ 287 from the OJ-94 project and found as well a probable period of 40 days in its optical variability during the late-1994 outburst. The results suggest that two components contribute to the variability of OJ 287 during its outburst state. The first component is the normal {\sl blazar} variation. This component has an amplitude similar to that of the quiescent state and also may share a similar periodicity. The second component can be taken as a `low-frequency modulation' to the first component. It may be induced by the interaction of the assumed binary black holes in the center of this object. The 40-day period may be related to the helical structure of the magnetic field at the base of the jet, or to the orbital motion close to the central primary black hole.Comment: 31 pages, 8 figures, accepted by A

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