1,128 research outputs found
Simulation of a 4-bed silica-gel-water adsorption chiller
Master'sMASTER OF ENGINEERIN
Joint Channel Assignment and Opportunistic Routing for Maximizing Throughput in Cognitive Radio Networks
In this paper, we consider the joint opportunistic routing and channel
assignment problem in multi-channel multi-radio (MCMR) cognitive radio networks
(CRNs) for improving aggregate throughput of the secondary users. We first
present the nonlinear programming optimization model for this joint problem,
taking into account the feature of CRNs-channel uncertainty. Then considering
the queue state of a node, we propose a new scheme to select proper forwarding
candidates for opportunistic routing. Furthermore, a new algorithm for
calculating the forwarding probability of any packet at a node is proposed,
which is used to calculate how many packets a forwarder should send, so that
the duplicate transmission can be reduced compared with MAC-independent
opportunistic routing & encoding (MORE) [11]. Our numerical results show that
the proposed scheme performs significantly better that traditional routing and
opportunistic routing in which channel assignment strategy is employed.Comment: 5 pages, 4 figures, to appear in Proc. of IEEE GlobeCom 201
The Narcissistic Gaze in Pipilotti Rist’s Video Work Mutaflor (1996)
The project focuses on the research of the visual culture in the context of western societies from the 1970s to the 1990s and the art criticism on video art during that time. The final product of this project is an art criticism on the video artwork Mutaflor, made by Pipilotti Rist, an internationally renowned contemporary video and installation artist
On the existence and structures of almost axisymmetric solutions to 3-D Navier-Stokes equations
In this paper, we consider 3-D Navier-Stokes equations with almost
axisymmetric initial data, which means that by writing in the cylindrical coordinates, then
and are small in some sense (recall axisymmetric means these three
quantities vanish). Then with additional smallness assumption on ,
we prove the global existence of a unique strong solution , and this
solution keeps close to some axisymmetric vector field. We also establish some
refined estimates for the integral average in variable for .
Moreover, as and here depend on , it is
natural to expand them into Fourier series in variable. And we shall
consider one special form of , with some small parameter to
measure its swirl part and oscillating part. We study the asymptotic expansion
of the corresponding solution, and the influences between different profiles in
the asymptotic expansion. In particular, we give some special symmetric
structures that will persist for all time. These phenomena reflect some
features of the nonlinear terms in Navier-Stokes equations
Code Completion by Modeling Flattened Abstract Syntax Trees as Graphs
Code completion has become an essential component of integrated development
environments. Contemporary code completion methods rely on the abstract syntax
tree (AST) to generate syntactically correct code. However, they cannot fully
capture the sequential and repetitive patterns of writing code and the
structural information of the AST. To alleviate these problems, we propose a
new code completion approach named CCAG, which models the flattened sequence of
a partial AST as an AST graph. CCAG uses our proposed AST Graph Attention Block
to capture different dependencies in the AST graph for representation learning
in code completion. The sub-tasks of code completion are optimized via
multi-task learning in CCAG, and the task balance is automatically achieved
using uncertainty without the need to tune task weights. The experimental
results show that CCAG has superior performance than state-of-the-art
approaches and it is able to provide intelligent code completion.Comment: Accepted in AAAI 2021. This version contains the appendix for the
derivation of Eq. 1
Differential geometric approach of Betchov-Da Rios soliton equation
MakaleWOS:000964265900009PubMed ID: 35296227In the present paper, we investigate differential geometric properties the soliton surface M associated with Betchov-Da Rios equation. Then, we give derivative formulas of Frenet frame of unit speed curve 4) = 4)(s, t) for all t. Also, we discuss the linear map of Weingarten type in the tangent space of the surface that generates two invariants: k and h. Moreover, we obtain the necessary and sufficient conditions for the soliton surface associated with Betchov-Da Rios equation to be a minimal surface. Finally, we examine a soliton surface associated with Betchov-Da Rios equation as an application. Mathematics Subject Classification (2020). 35Q55, 53A05National Natural Science Foundation of China (NSFC
Enabling CMF Estimation in Data-Constrained Scenarios: A Semantic-Encoding Knowledge Mining Model
Precise estimation of Crash Modification Factors (CMFs) is central to
evaluating the effectiveness of various road safety treatments and prioritizing
infrastructure investment accordingly. While customized study for each
countermeasure scenario is desired, the conventional CMF estimation approaches
rely heavily on the availability of crash data at given sites. This not only
makes the estimation costly, but the results are also less transferable, since
the intrinsic similarities between different safety countermeasure scenarios
are not fully explored. Aiming to fill this gap, this study introduces a novel
knowledge-mining framework for CMF prediction. This framework delves into the
connections of existing countermeasures and reduces the reliance of CMF
estimation on crash data availability and manual data collection. Specifically,
it draws inspiration from human comprehension processes and introduces advanced
Natural Language Processing (NLP) techniques to extract intricate variations
and patterns from existing CMF knowledge. It effectively encodes unstructured
countermeasure scenarios into machine-readable representations and models the
complex relationships between scenarios and CMF values. This new data-driven
framework provides a cost-effective and adaptable solution that complements the
case-specific approaches for CMF estimation, which is particularly beneficial
when availability of crash data or time imposes constraints. Experimental
validation using real-world CMF Clearinghouse data demonstrates the
effectiveness of this new approach, which shows significant accuracy
improvements compared to baseline methods. This approach provides insights into
new possibilities of harnessing accumulated transportation knowledge in various
applications.Comment: 39 pages, 9 figure
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