Star formation associated with a large-scale infrared bubble

Using the data from the Galactic Ring Survey (GRS) and Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE), we performed a study for a large-scale infrared bubble with a size of about 16 pc at a distance of 2.0 kpc. We present the 12CO J=1-0, 13CO J=1-0 and C18O J=1-0 observations of HII region G53.54-0.01 (Sh2-82) obtained at the the Purple Mountain Observation (PMO) 13.7 m radio telescope to investigate the detailed distribution of associated molecular material. The large-scale infrared bubble shows a half-shell morphology at 8 um. H II regions G53.54-0.01, G53.64+0.24, and G54.09-0.06 are situated on the bubble. Comparing the radio recombination line velocities and associated 13CO J=1-0 components of the three H II regions, we found that the 8 um emission associated with H II region G53.54-0.01 should belong to the foreground emission, and only overlap with the large-scale infrared bubble in the line of sight. Three extended green objects (EGOs, the candidate massive young stellar objects), as well as three H II regions and two small-scale bubbles are found located in the G54.09-0.06 complex, indicating an active massive star-forming region. C18O J=1-0 emission presents four cloud clumps on the northeastern border of H II region G53.54-0.01. Via comparing the spectral profiles of 12CO J=1-0, 13CO J=1-0, and C18O J=1-0 peak at each clump, we found the collected gas in the three clumps, except for the clump coincided with a massive YSO (IRAS 19282+1814). Using the evolutive model of H II region, we derived that the age of H II region G53.54-0.01 is 1.5*10^6 yr. The significant enhancement of several Class I and Class II YSOs around G53.54-0.01 indicates the presence of some recently formed stars, which may be triggered by this H II region through the collect and collapse (CC) process.Comment: 9 pages, 6 figures, accepted for publication in A&

Holographic R\'enyi entropy for CFT with WW symmetry

In this paper we investigate the holographic R\'enyi entropy of two disjoint intervals on complex plane with small cross ratio $x$ for conformal field theory with $W$ symmetry in the ground state, which could be dual to a higher spin AdS$_3$ gravity. We focus on the cases of $W_3$ and $W_4$ symmetries. In order to see the nontrivial contributions from the $W$ fields, we calculate the R\'enyi entropy in the expansion of $x$ to order $x^8$ in both the gravity and the CFT sides. In the gravity side the classical contributions to the entanglement entropy is still given by the Ryu-Takayanagi area formula under the reasonable assumption, while the 1-loop quantum corrections have to take into account of the contributions not only from massless gravitons, but also from massless higher spin fields. In the CFT side we still use the operator product expansion of twist operators in the small interval limit, but now we need to consider the quasiprimary fields constructed from $W$ fields, besides the ones from Virasoro Verma module. In the large central charge limit, we obtain the classical, 1-loop, 2-loop, and 3-loop parts of the R\'enyi entropy. The classical and 1-loop results in the gravity and the CFT sides are in exact match. This confirms the higher spin gravity/CFT correspondence, and also supports the holographic computation of R\'enyi entanglement entropy, including the quantum correction, in both the AdS$_3$ gravity and the higher spin AdS$_3$ gravity.Comment: 32 pages, published versio

Hidden Conformal Symmetry of Extremal Black Holes

We study the hidden conformal symmetry of the extremal black holes. We introduce a new set of conformal coordinates to write the $SL(2,R)$ generators. We find that the Laplacian of the scalar field in many extremal black holes could be written in terms of the $SL(2,R)$ quadratic Casimir. This suggests that there exist dual CFT descriptions of these black holes. From the conformal coordinates, the temperatures of the dual CFTs could be read directly. For the extremal black hole, the Hawking temperature is vanishing. Correspondingly, only the left (right) temperature of the dual CFT is non-vanishing and the excitations of the other sector are suppressed. In the probe limit, we compute the scattering amplitudes of the scalar off the extremal black holes and find perfect agreement with the CFT prediction.Comment: 16 pages; Published versio

Interaction-aware Kalman Neural Networks for Trajectory Prediction

Forecasting the motion of surrounding obstacles (vehicles, bicycles, pedestrians and etc.) benefits the on-road motion planning for intelligent and autonomous vehicles. Complex scenes always yield great challenges in modeling the patterns of surrounding traffic. For example, one main challenge comes from the intractable interaction effects in a complex traffic system. In this paper, we propose a multi-layer architecture Interaction-aware Kalman Neural Networks (IaKNN) which involves an interaction layer for resolving high-dimensional traffic environmental observations as interaction-aware accelerations, a motion layer for transforming the accelerations to interaction aware trajectories, and a filter layer for estimating future trajectories with a Kalman filter network. Attributed to the multiple traffic data sources, our end-to-end trainable approach technically fuses dynamic and interaction-aware trajectories boosting the prediction performance. Experiments on the NGSIM dataset demonstrate that IaKNN outperforms the state-of-the-art methods in terms of effectiveness for traffic trajectory prediction.Comment: 8 pages, 4 figures, Accepted for IEEE Intelligent Vehicles Symposium (IV) 202

Are All Open Source Projects Created Equal? Understanding the Sustainability of Open Source Software Development Model

A very intriguing question in Open Source software (OSS) development is: why there are only a few open source projects succeed, while the majority of projects never do. In this research, we examine the factors that may influence the performance of OSS projects. We particularly focus on the OSS’s core developers’ role in the project’s success. Extant research has yet to distinguish core developers and non-core developers from the community at large. The different roles of the core developers and non-core developers in OSS projects’ success still remain unclear. Our research contributes to the literature by separating the core developers from the development forces in general and empirically examining the core developers’ importance. Drawing the evidences from our extensive dataset of 300 open source projects, we demonstrated that core developers’ leadership and project advocation are crucial in determining the fate of the OSS projects. Our research could provide better understanding of OSS sustainability. It could also give practical advice to the OSS community on how to make the project successful

Poecilostomatoid Copepods Parasitic in Bivalve Mollusks of Taiwan

Three species of poecilostomatoid copepods parasitic in bivalve mollusks of Taiwan were described. They are: Ostrincola simi/is sp. nov. from the cultured oyster, Crassostrea gigas (Thunberg), and green mussel, Perna viridis (Linnaeus), attached to this species of oyster; Myicola formosanus sp. nov. from the circular clam, Cyclina sinensis (Gmelin); and Anthessius mytilicolus Reddiah, 1966 from the green mussels attached to the cultured C. gigas. This is the first report of parasitic copepods from the bivalve mollusks of Taiwan

How IT Awareness Impacts IT Control Weaknesses and Firm Performance

With the prevalence of information technology (IT), the value of IT awareness increasingly grows, and IT control becomes a key part of firms’ strategies and objectives. Although leadership plays an important role in IT control governance, limited research has studied whether IT awareness is associated with IT control weaknesses (ITCWs) and firm performance simultaneously. Drawing on the agency and resource dependence theory, this paper proposes an integrative model to examine the impact of IT awareness on ITCWs and firm performance. We empirically validate the model using a data set of 310 firms collected from multiple sources including Audit Analytics, Compustat, 10-K filings, and proxy statement. The findings indicate that firms with higher IT awareness are less likely to have ITCWs, and lead to improved firm performance. This paper contributes to information systems (IS) literature by investigating the IT experience and knowledge of the board of directors on both ITCWs and firm performance. This study also provides important practical implications for IT management practices

Using Document Indexers for Faceted Search in Dataspaces

Efficient information retrieval is essential to enrich user experience when searching for documents in dataspaces. With the continued growth in the volume and complexity of documents, the efficient information retrieval for searches has become increasingly challenging. To improve users’ search experience, faceted search combines direct keyword search methods with faceted browsing using a predefined set of categories (facets). This paper studies a faceted search approach that integrates dynamic facets generation with search. To further enhance the faceted search, alternative indexers based on pre-defined ontology for data repositories within dataspaces are evaluated in terms of execution time and data size. Experimental results suggest that combining the proposed faceted search with appropriate indexers improves search performance enhancing user experience