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An Application-Aware Spectrum Sharing Approach for Commercial Use of 3.5 GHz Spectrum  [PDF]
Haya Shajaiah,Ahmed Abdelhadi,Charles Clancy
Computer Science , 2015,
Abstract: In this paper, we introduce an application-aware spectrum sharing approach for sharing the Federal under-utilized 3.5 GHz spectrum with commercial users. In our model, users are running elastic or inelastic traffic and each application running on the user equipment (UE) is assigned a utility function based on its type. Furthermore, each of the small cells users has a minimum required target utility for its application. In order for users located under the coverage area of the small cells' eNodeBs, with the 3.5 GHz band resources, to meet their minimum required quality of experience (QoE), the network operator makes a decision regarding the need for sharing the macro cell's resources to obtain additional resources. Our objective is to provide each user with a rate that satisfies its application's minimum required utility through spectrum sharing approach and improve the overall QoE in the network. We present an application-aware spectrum sharing algorithm that is based on resource allocation with carrier aggregation to allocate macro cell permanent resources and small cells' leased resources to UEs and allocate each user's application an aggregated rate that can at minimum achieves the application's minimum required utility. Finally, we present simulation results for the performance of the proposed algorithm.
A Sharing- and Competition-Aware Framework for Cellular Network Evolution Planning  [PDF]
Paolo Di Francesco,Francesco Malandrino,Tim K. Forde,Luiz A. DaSilva
Computer Science , 2015,
Abstract: Mobile network operators are facing the difficult task of significantly increasing capacity to meet projected demand while keeping CAPEX and OPEX down. We argue that infrastructure sharing is a key consideration in operators' planning of the evolution of their networks, and that such planning can be viewed as a stage in the cognitive cycle. In this paper, we present a framework to model this planning process while taking into account both the ability to share resources and the constraints imposed by competition regulation (the latter quantified using the Herfindahl index). Using real-world demand and deployment data, we find that the ability to share infrastructure essentially moves capacity from rural, sparsely populated areas (where some of the current infrastructure can be decommissioned) to urban ones (where most of the next-generation base stations would be deployed), with significant increases in resource efficiency. Tight competition regulation somewhat limits the ability to share but does not entirely jeopardize those gains, while having the secondary effect of encouraging the wider deployment of next-generation technologies.
Mobile and Context-Aware GeoBI Applications: A Multilevel Model for Structuring and Sharing of Contextual Information  [PDF]
Belko Abdoul Aziz Diallo, Thierry Badard, Frédéric Hubert, Sylvie Daniel
Journal of Geographic Information System (JGIS) , 2012, DOI: 10.4236/jgis.2012.45048
Abstract: With the requirements for high performance results in the today’s mobile, global, highly competitive, and technology-based business world, business professionals have to get supported by convenient mobile decision support systems (DSS). To give an improved support to mobile business professionals, it is necessary to go further than just allowing a simple remote access to a Business Intelligence platform. In this paper, the need for actual context-aware mobile Geospatial Business Intelligence (GeoBI) systems that can help capture, filter, organize and structure the user mobile context is exposed and justified. Furthermore, since capturing, structuring, and modeling mobile contextual information is still a research issue, a wide inventory of existing research work on context and mobile context is provided. Then, step by step, we methodologically identify relevant contextual information to capture for mobility purposes as well as for BI needs, organize them into context-dimensions, and build a hierarchical mobile GeoBI context model which (1) is geo-spatial-extended, (2) fits with human perception of mobility, (3) takes into account the local context interactions and information-sharing with remote contexts, and (4) matches with the usual hierarchical aggregated structure of BI data.
A Dynamic Model of Mixed Duopolistic Competition: Open Source vs. Proprietary Innovation  [PDF]
Suat Akbulut, Murat Y?lmaz
Theoretical Economics Letters (TEL) , 2015, DOI: 10.4236/tel.2015.56085
Abstract: We model the competition between a proprietary firm and an open source rival, by incorporating the nature of the GPL, investment opportunities by the proprietary firm, user-developers who can invest in the open source development, and a ladder type technology. We use a two-period dynamic mixed duopoly model, in which a profit-maximizing proprietary firm competes with a rival, the open source firm, which prices the product at zero, with the quality levels determining their relative positions over time. We analyze how the existence of open source firm affects the investment and the pricing behavior of the proprietary firm. We also study the welfare implications of the existence of the open source rival. We find that, under some conditions, the existence of an open source rival may decrease the total welfare.
Proprietary software versus Open Source Software for Education  [PDF]
N. Pankaja
American Journal of Engineering Research , 2013,
Abstract: The Internet has brought learning "online" and offers many advantages. It is convenient, available at any time of the day, and can be accessed nearly anywhere in the world. Recently, Cloud computing is all the rage. E-Learning offers tremendous potential to increase the availability and convenience of education. Today, online content is varied and can include: text on a website, digital audio, digital video, animated images, and virtual reality environments. This content can be created in a variety of ways by utilizing a variety of authoring tools and softwares. These days, we observe a movement in higher education leading from proprietary software to open source, for e-learning applications (1) In fact, open source software (OSS) development can provide the necessary flexibility to combine languages, scripts, learning objects and lesson plans, effectively, without the cost and rigidity of proprietary software. In recent years, numerous open access LMS software s have emerged as viable alternatives to costly proprietary and commercial products. Open source software s of Content Management Systems (CMS) and Learning Management System (LMS) are gaining popularity. We weigh the pro s and cons of utilizing the OSS and proprietary software in this paper.
Quality of service monitoring: Performance metrics across proprietary content domains  [PDF]
Shawn O'Donnell,Hugh Carter Donahue,Josephine Ferrigno-Stack
Computer Science , 2001,
Abstract: We propose a quality of service (QoS) monitoring program for broadband access to measure the impact of proprietary network spaces. Our paper surveys other QoS policy initiatives, including those in the airline, and wireless and wireline telephone industries, to situate broadband in the context of other markets undergoing regulatory devolution. We illustrate how network architecture can create impediments to open communications, and how QoS monitoring can detect such effects. We present data from a field test of QoS-monitoring software now in development. We suggest QoS metrics to gauge whether information "walled gardens" represent a real threat for dividing the Internet into proprietary spaces. To demonstrate our proposal, we are placing our software on the computers of a sample of broadband subscribers. The software periodically conducts a battery of tests that assess the quality of connections from the subscriber's computer to various content sites. Any systematic differences in connection quality between affiliated and non-affiliated content sites would warrant research into the behavioral implications of those differences. QoS monitoring is timely because the potential for the Internet to break into a loose network of proprietary content domains appears stronger than ever. Recent court rulings and policy statements suggest a growing trend towards relaxed scrutiny of mergers and the easing or elimination of content ownership rules. This policy environment could lead to a market with a small number of large, vertically integrated network operators, each pushing its proprietary content on subscribers.
Disconnectivity and Relative Positions in Simultaneous Embeddings  [PDF]
Thomas Bl?sius,Ignaz Rutter
Computer Science , 2012,
Abstract: The problem Simultaneous Embedding with Fixed Edges (SEFE) asks for two planar graph $G^1 = (V^1, E^1)$ and $G^2 = (V^2, E^2)$ sharing a common subgraph $G = G^1 \cap G^2$ whether they admit planar drawings such that the common graph is drawn the same in both. Previous results on this problem require $G$, $G^1$ and $G^2$ to be connected. This paper is a first step towards solving instances where these graphs are disconnected. First, we show that an instance of the general SEFE-problem can be reduced in linear time to an equivalent instance where $V^1 = V^2$ and $G^1$ and $G^2$ are connected. This shows that it can be assumed without loss of generality that both input graphs are connected. Second, we consider instances where $G$ is disconnected. We show that SEFE can be solved in linear time if $G$ is a family of disjoint cycles by introducing the CC-tree, which represents all simultaneous embeddings. We extend these results (including the CC-tree) to the case where $G$ consists of arbitrary connected components, each with a fixed embedding. Note that previous results require $G$ to be connected and thus do not need to care about relative positions of connected components. By contrast, we assume the embedding of each connected component to be fixed and thus focus on these relative positions. As SEFE requires to deal with both, embeddings of connected components and their relative positions, this complements previous work.
Perceived Positions Determine Crowding  [PDF]
Gerrit W. Maus,Jason Fischer,David Whitney
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0019796
Abstract: Crowding is a fundamental bottleneck in object recognition. In crowding, an object in the periphery becomes unrecognizable when surrounded by clutter or distractor objects. Crowding depends on the positions of target and distractors, both their eccentricity and their relative spacing. In all previous studies, position has been expressed in terms of retinal position. However, in a number of situations retinal and perceived positions can be dissociated. Does retinal or perceived position determine the magnitude of crowding? Here observers performed an orientation judgment on a target Gabor patch surrounded by distractors that drifted toward or away from the target, causing an illusory motion-induced position shift. Distractors in identical physical positions led to worse performance when they drifted towards the target (appearing closer) versus away from the target (appearing further). This difference in crowding corresponded to the difference in perceived positions. Further, the perceptual mislocalization was necessary for the change in crowding, and both the mislocalization and crowding scaled with drift speed. The results show that crowding occurs after perceived positions have been assigned by the visual system. Crowding does not operate in a purely retinal coordinate system; perceived positions need to be taken into account.
Relative positions of matroid algebras  [PDF]
S. C. Power
Mathematics , 1998,
Abstract: A classification is given for (regular) positions of direct sums of two matroid algebras (unital algebraic limits of matrix algebras) in a matroid superalgebra, where the individual summands have index 2 in their associated corner algebra. A similar classification is obtained for positions of direct sums of 2-symmetric algebras and, in the odd case, for the positions of sums of 2-symmetric C*-algebras in matroid C*-algebras. The approach relies on an analysis of intermediate non-self-adjoint operator algebras and the classifications are given in terms of K0 invariants, partial isometry homology and scales in the associated composite K0-homology group.
How accurate are SuperCOSMOS positions?  [PDF]
Adam Schaefer,Richard Hunstead,Helen Johnston
Physics , 2014, DOI: 10.1017/pasa.2014.4
Abstract: Optical positions from the SuperCOSMOS Sky Survey have been compared in detail with accurate radio positions that define the second realisation of the International Celestial Reference Frame (ICRF2). The comparison was limited to the IIIaJ plates from the UK/AAO and Oschin (Palomar) Schmidt telescopes. A total of 1373 ICRF2 sources was used, with the sample restricted to stellar objects brighter than $B_J=20$ and Galactic latitudes $|b|>10^{\circ}$. Position differences showed an rms scatter of $0.16''$ in right ascension and declination. While overall systematic offsets were $<0.1''$ in each hemisphere, both the systematics and scatter were greater in the north.
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