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The tool FLOW* performs Taylor model-based flowpipe construction for non-linear (polynomial) hybrid systems. FLOW* combines well-known Tay-lor model arithmetic techniques for guaranteed approximations of the continuous dynamics in each mode with a combination of approaches for handling mode invariants and discrete transitions. FLOW* supports a wide variety(More)
—We propose an approach for verifying non-linear hybrid systems using higher-order Taylor models that are a combination of bounded degree polynomials over the initial conditions and time, bloated by an interval. Taylor models are an effective means for computing rigorous bounds on the complex time trajectories of non-linear differential equations. As a(More)
In densely populated cities like Hong Kong, GPS alone is not sufficient in providing rich location based information services. In this work, we provide a mobile location search service by allowing users shooting a short video clip about the surrounding buildings and the Cloud will return a tagged image with a summary of the location and services available.(More)
We investigate linear programming relaxations to synthesize Lyapunov functions that establish the stability of a given system over a bounded region. In particular, we attempt to discover functions that are more readily useful inside symbolic verification tools for proving the correctness of control systems. Our approach searches for a Lyapunov function,(More)
Laser scanning enables to measure a huge number of 3D points in a few time. However, the creation of a 3D model from these data remains an involving work. We introduce a method to get this modeling task easier. Our approach is twofold. On the one hand, a camera is coupled to the laser scanner in order to drive the scan by image analysis. On the other hand,(More)
We examine linear programming (LP) based relaxations for synthesizing polynomial Lyapunov functions to prove the stability of polynomial ODEs. Our approach starts from a desired parametric polynomial form of the polynomial Lyapunov function. Subsequently, we encode the positive-definiteness of the function, and the negation of its derivative, over the(More)
Web logs record actions and behaviors of users. By mining and analyzing these logs we can find users browsing and access patterns, and this is very important and useful to the web site optimization and recommender. This paper first analyses the association-rules-based personalized recommender model which is very popular in web site recommender system,(More)
This paper studies the effect of parameter variation on the behavior of analog circuits at the transistor (netlist) level. It is well known that variation in key circuit parameters can often adversely impact the correctness and performance of analog circuits during fabrication. An important problem lies in characterizing a <i>safe subset</i> of the(More)
—We propose an approach for computing under-as well as over-approximations for the reachable sets of continuous systems which are defined by non-linear Ordinary Differential Equations (ODEs). Given a compact and connected initial set of states, described by a system of polynomial inequalities, we compute under-approximations of the set of states reachable(More)