Implementations of the Bayes filtering for vision based aircraft tracking suffer fundamental difficulties in the Cartesian coordinate. This is because of the uncertainty of the noise model in the flight dynamic equation when the aircraft state is described in these coordinates. Recently, the Logarithmic Polar Coordinate (LPC) framework has been successfully applied in the bearings-only tracking...

Data from computational fluid dynamics (CFD) are frequently computed on curvilinear grids. In contrast to cartesian or uniform grids, the cell size in a curvilinear grid can vary significantly, which in turn complicates filter operations tremendously. Some of these filter operations may for example re-map the value range of the data values into another range. In this paper, we present adaptive ...

User manipulation of assembly models can provide insight during the early, formulative design stages into kinematic and dynamic characteristics of a mechanism. We present the advantages of kinematic representation of constraint equations in fully Cartesian coordinates, a departure from standard practice for interactive mechanical assembly at interactive rates. Formulations of a surface rolling ...

Real-time three-dimensional (RT3D) ultrasound technique based on matrix phased array transducers is likely to become predominant for dynamic screening in cardiac and obstetric practice. With these transducers large data volumes are acquired in spherical coordinates and require resampling to be visualized in Cartesian coordinates. A fast 3D resampling method was implemented and five interpolatio...

The set of coordinates used to describe the motion of a dynamic system is not unique. For example, consider an elastic pendulum (a mass on the end of a spring). The position of the mass at any point in time may be expressed in Cartesian coordinates (x(t), y(t)) or in terms of the angle of the pendulum and the stretch of the spring (θ(t), u(t)). Of course, these two coordinate systems are relate...

This paper describes a new parallel kinematic architecture for machining applications: the orthoglide. This machine features three fixed parallel linear joints which are mounted orthogonally and a mobile platform which moves in the Cartesian x-y-z space with fixed orientation. The main interest of the orthoglide is that it takes benefit from the advantages of the popular PPP serial machines (re...

This article summarises some considerations surrounding a geoid-model-based vertical datum that have to be thought through before its implementation and adoption. Our examples are based on many Australian and some South-East Asian experiences, but these probably also apply elsewhere. Thekey considerations comprisedataquality andavailability, politics, anddifficulties thatusersmayencounterwhen a...

This paper describes the application of a new and unconventional numerical method for computational modeling of fluidic micro-handling processes. The key requirement for modeling such processes is the ability to simulate flows with large number of complex shaped moving objects. Conventional body-conformal computational fluid dynamic (CFD) methods are not well suited for simulating such flows an...

Verifying concurrent programs is challenging since the number of thread interleavings that need to be explored can be huge even for moderate programs. We present a cartesian semantics that reduces the amount of nondeterminism in concurrent programs by delaying unnecessary context switches. Using this semantics, we construct a novel dynamic partial-order reduction algorithm. The cartesian semant...