1874338
The MicroGrid: a Scientific Tool for Modeling Computational Grids
The complexity and dynamic nature of the Internet (and the emerging Computational Grid) demand that middleware and applications adapt to the changes in configuration and availability of resources. However, to the best of our knowledge there are no simulation tools which support systematic exploration of dynamic Grid software (or Grid resource) behavior. We describe our vision and initial efforts to build tools to meet these needs. Our MicroGrid simulation tools enable Globus applications to be run in arbitrary virtual grid resource environments, enabling broad experimentation. We describe the design of these tools, and their validation on micro- benchmarks, the NA parallel benchmarks, and an entire Grid application. These validation experiments show that the MicroGrid can match actual experiments within a few percent (2% to 4%).
59116191
A High Accuracy Printed Traditional and Simplified Chinese Character Document Recognition System
59762733
The application of artificial neural networks in editing noisy seismic data
206756450
Nonlinear Dimensionality Reduction by Locally Linear Inlaying
High-dimensional data is involved in many fields of information processing. However, sometimes, the intrinsic structures of these data can be described by a few degrees of freedom. To discover these degrees of freedom or the low-dimensional nonlinear manifold underlying a high-dimensional space, many manifold learning algorithms have been proposed. Here we describe a novel algorithm, locally linear inlaying (LLI), which combines simple geometric intuitions and rigorously established optimality to compute the global embedding of a nonlinear manifold. Using a divide-and-conquer strategy, LLI gains some advantages in itself. First, its time complexity is linear in the number of data points, and hence LLI can be implemented efficiently. Second, LLI overcomes problems caused by the nonuniform sample distribution. Third, unlike existing algorithms such as isometric feature mapping (Isomap), local tangent space alignment (LTSA), and locally linear coordination (LLC), LLI is robust to noise. In addition, to evaluate the embedding results quantitatively, two criteria based on information theory and Kolmogorov complexity theory, respectively, are proposed. Furthermore, we demonstrated the efficiency and effectiveness of our proposal by synthetic and real-world data sets.
11105544
Solving Computational Fluid Dynamics Problems on Unstructured Grids with Distributed Parallel Processing
This paper describes a distributed parallel implementation of a finite element method for simulating incompressible viscous flows. When applied to unstructured finite element meshes, a conventional implementation of this algorithm becomes particularly space demanding for the storage of system matrices. This parallel implementation not only results in a faster computation but is also potentially capable of solving much larger problems as data and system matrix blocks are distributed. Experimental results demonstrating these key features are presented.
15643716
Optimal Memory Rendezvous of Anonymous Mobile Agents in a Unidirectional Ring
We study the rendezvous problem with k≥2 mobile agents in a n-node ring. We present a new algorithm which solves the rendezvous problem for any non-periodic distribution of agents on the ring. The mobile agents require the use of O(log k)–bit-wise size of internal memory and one indistinguishable token each. In the periodic (but not symmetric) case our new procedure allows the agents to conclude that rendezvous is not feasible. It is known that in the symmetric case the agents cannot decide the feasibility of rendezvous if their internal memory is limited to ω(loglog n) bits, see [15]. In this context we show new space optimal deterministic algorithm allowing effective recognition of the symmetric case. The algorithm is based on O(log k + loglog n)-bit internal memory and a single token provided to each mobile agent. Finally, it is known that both in the periodic as well as in the symmetric cases the rendezvous cannot be accomplished by any deterministic procedure due to problems with breaking symmetry.
35595997
Parallel simulation of a multi-dimensional computational fluid dynamics problem
The simulation of computational fluid dynamics problems in two and more dimensions involves computations of multiple degrees of freedom, such as the components of velocity, which are an obvious source of parallelism. Further to our previous investigation in this area we report on our current experiences in extracting such parallelism on a distributed network platform. A finite element method for simulating incompressible viscous flows is parallelised using a domain decomposition approach. Various issues that arise in this implementation are discussed in the light of our experimental results.
39876273
A Dependable Micro-Electronic Peptide Synthesizer Using Electrode Data
The research in the area of microelectronic fluidic devices for biomedical applications is rapidly growing. As faults in these devices can have serious personal implications, a system is presented which includes fault tolerance with respect to the synthesized biomaterials (peptides). It can employ presence and purity detection of peptide droplets via current (charge) tests of control electrodes or impedance (phase) measurements using direct sensing electrodes near the peptide collector area. The commercial multielectrode array performs better in pure and impure detection of peptides in impedance and phase. Our two-electrode X-MEF case shows slightly poorer results. In both cases the phase is the best choice for contents detection. If there are presence or purity problems, the location is marked, and repeated peptide synthesis at another collector site is initiated.
15371796
ACTIVE: agile coordinator testbed integrated virtual environment
This paper describes the specification, design and development of ACTIVE, a testbed for the testing and simulation of large-scale agent-based systems. ACTIVE is being developed as part of DARPA's Coordinators program. The goal of the ACTIVE testbed is to support the simulation of large collections of distributed cooperating agents in solving constrained scheduling problems.