1,549 research outputs found
Overview of Development and Recent Trends in Bibliometrics and Research Evaluation
This paper is an overview of bibliometrics, a subfield of library and information science. It briefly explains what bibliometrics is and why it is important in research evaluation and impact analysis. It summarizes the latest development and trends over the past decade. Three major trends are identified and discussed. They are alternative metrics, responsible use of bibliometrics and responsible research evaluation movement, and application of artificial intelligence (AI) and machine learning in bibliometrics practice
Pairwise Quantum Correlations for Superpositions of Dicke States
Pairwise correlation is really an important property for multi-qubit states.
For the two-qubit X states extracted from Dicke states and their superposition
states, we obtain a compact expression of the quantum discord by numerical
check. We then apply the expression to discuss the quantum correlation of the
reduced two-qubit states of Dicke states and their superpositions, and the
results are compared with those obtained by entanglement of formation, which is
a quantum entanglement measure.Comment: 17pages, 8 figures,slightly improved and slightly extended
version,and added some reference
The Provision and Sustainability of GIS Services: How an Academic Library without a GIS Specialist Provides GIS Services
This paper presents a case study of how one academic library provides services and support for the Geographic Information System (GIS) needs of students and faculty. The case study involves an American university library that has provided GIS services to meet the needs of students and faculty while lacking the formal position of a dedicated GIS Librarian. The library’s variety of GIS-related support is described in the paper, and an overview of resources for librarians to develop their GIS skills is also shared. The paper offers insights and lessons learned about the level of services that can be offered by academic libraries in GIS-related research and training for students, faculty, and staff
Editorial: Special Issue on Pandemic and Libraries
Editorial: Special Issue on Pandemic and Librarie
Codebook Based Hybrid Precoding for Millimeter Wave Multiuser Systems
In millimeter wave (mmWave) systems, antenna architecture limitations make it
difficult to apply conventional fully digital precoding techniques but call for
low cost analog radio-frequency (RF) and digital baseband hybrid precoding
methods. This paper investigates joint RF-baseband hybrid precoding for the
downlink of multiuser multi-antenna mmWave systems with a limited number of RF
chains. Two performance measures, maximizing the spectral efficiency and the
energy efficiency of the system, are considered. We propose a codebook based RF
precoding design and obtain the channel state information via a beam sweep
procedure. Via the codebook based design, the original system is transformed
into a virtual multiuser downlink system with the RF chain constraint.
Consequently, we are able to simplify the complicated hybrid precoding
optimization problems to joint codeword selection and precoder design (JWSPD)
problems. Then, we propose efficient methods to address the JWSPD problems and
jointly optimize the RF and baseband precoders under the two performance
measures. Finally, extensive numerical results are provided to validate the
effectiveness of the proposed hybrid precoders.Comment: 35 pages, 9 figures, to appear in Trans. on Signal Process, 201
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