175 research outputs found
The model checking problem for intuitionistic propositional logic with one variable is AC1-complete
We show that the model checking problem for intuitionistic propositional
logic with one variable is complete for logspace-uniform AC1. As basic tool we
use the connection between intuitionistic logic and Heyting algebra, and
investigate its complexity theoretical aspects. For superintuitionistic logics
with one variable, we obtain NC1-completeness for the model checking problem.Comment: A preliminary version of this work was presented at STACS 2011. 19
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The model checking problem for propositional intuitionistic logic with one variable is AC^1-complete
We investigate the complexity of the model checking problem for propositional intuitionistic logic. We show that the model checking problem for intuitionistic logic with one variable is complete for logspace-uniform AC^1, and for intuitionistic logic with two variables it is P-complete. For superintuitionistic logics with one variable, we obtain NC^1-completeness for the model checking problem and for the tautology problem
The model checking fingerprints of CTL operators
The aim of this study is to understand the inherent expressive power of CTL
operators. We investigate the complexity of model checking for all CTL
fragments with one CTL operator and arbitrary Boolean operators. This gives us
a fingerprint of each CTL operator. The comparison between the fingerprints
yields a hierarchy of the operators that mirrors their strength with respect to
model checking
Model Checking CTL is Almost Always Inherently Sequential
The model checking problem for CTL is known to be P-complete (Clarke, Emerson, and Sistla (1986), see Schnoebelen (2002)). We consider fragments of CTL obtained by restricting the use of temporal modalities or the use of negations—restrictions already studied for LTL by Sistla and Clarke (1985) and Markey (2004). For all these fragments, except for the trivial case without any temporal operator, we systematically prove model checking to be either inherently sequential (P-complete) or very efficiently parallelizable (LOGCFL-complete). For most fragments, however, model checking for CTL is already P-complete. Hence our results indicate that in most applications, approaching CTL model checking by parallelism will not result in the desired speed up. We also completely determine the complexity of the model checking problem for all fragments of the extensions ECTL, CTL +, and ECTL +
mCLCA3 Modulates IL-17 and CXCL-1 Induction and Leukocyte Recruitment in Murine Staphylococcus aureus Pneumonia
The human hCLCA1 and its murine ortholog mCLCA3 (calcium-activated chloride
channel regulators) are exclusively expressed in mucus cells and linked to
inflammatory airway diseases with increased mucus production, such as asthma,
cystic fibrosis and chronic obstructive pulmonary disease. Both proteins have
a known impact on the mucus cell metaplasia trait in these diseases. However,
growing evidence points towards an additional role in innate immune responses.
In the current study, we analyzed Staphylococcus aureus pneumonia, an
established model to study pulmonary innate immunity, in mCLCA3-deficient and
wild-type mice, focusing on the cellular and cytokine-driven innate
inflammatory response. We compared clinical signs, bacterial clearance,
leukocyte immigration and cytokine responses in the bronchoalveolar
compartment, as well as pulmonary vascular permeability, histopathology, mucus
cell number and mRNA expression levels of selected genes (mClca1 to 7, Muc5ac,
Muc5b, Muc2, Cxcl-1, Cxcl-2, Il-17). Deficiency of mCLCA3 resulted in
decreased neutrophilic infiltration into the bronchoalveolar space during
bacterial infection. Only the cytokines IL-17 and the murine CXCL-8 homolog
CXCL-1 were decreased on mRNA and protein levels during bacterial infection in
mCLCA3-deficient mice compared to wild-type controls. However, no differences
in clinical outcome, histopathology or mucus cell metaplasia were observed. We
did not find evidence for regulation of any other CLCA homolog that would
putatively compensate for the lack of mCLCA3. In conclusion, mCLCA3 appears to
modulate leukocyte response via IL-17 and murine CXCL-8 homologs in acute
Staphylococcus aureus pneumonia which is well in line with the proposed
function of hCLCA1 as a signaling molecule acting on alveolar macrophages
VEGa : a high performance vehicular Ethernet gateway on hybrid FPGA
Modern vehicles employ a large amount of distributed computation and require the underlying communication scheme to provide high bandwidth and low latency. Existing communication protocols like Controller Area Network (CAN) and FlexRay do not provide the required bandwidth, paving the way for adoption of Ethernet as the next generation network backbone for in-vehicle systems. Ethernet would co-exist with safety-critical communication on legacy networks, providing a scalable platform for evolving vehicular systems. This requires a high-performance network gateway that can simultaneously handle high bandwidth, low latency, and isolation; features that are not achievable with traditional processor based gateway implementations. We present VEGa, a configurable vehicular Ethernet gateway architecture utilising a hybrid FPGA to closely couple software control on a processor with dedicated switching circuit on the reconfigurable fabric. The fabric implements isolated interface ports and an accelerated routing mechanism, which can be controlled and monitored from software. Further, reconfigurability enables the switching behaviour to be altered at run-time under software control, while the configurable architecture allows easy adaptation to different vehicular architectures using high-level parameter settings. We demonstrate the architecture on the Xilinx Zynq platform and evaluate the bandwidth, latency, and isolation using extensive tests in hardware
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