Systems of polynomial equations over an algebraically-closed field K can be used to concisely model many combinatorial problems. In this way, a combinatorial problem is feasible (e.g., a graph is 3-colorable, hamilton...
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ISBN:
(纸本)9781595939043
Systems of polynomial equations over an algebraically-closed field K can be used to concisely model many combinatorial problems. In this way, a combinatorial problem is feasible (e.g., a graph is 3-colorable, hamiltonian, etc.) if and only if a related system of polynomial equations has a solution over K. In this paper, we investigate an algorithm aimed at proving combinatorial infeasibility based on the observed low degree of Hilbert's Nullstellensatz certificates for polynomial systems arising in combinatorics and on large-scale linear-algebra computations over K. We report on experiments based on the problem of proving the non-3-colorability of graphs. We successfully solved graph problem instances having thousands of nodes and tens of thousands of edges.
We present a new model of unsupervised competitive neural network, based on spicules. This model is capable of detecting topological information of an input space, determining its orientation and, in most case, its sk...
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ISBN:
(纸本)2930307099
We present a new model of unsupervised competitive neural network, based on spicules. This model is capable of detecting topological information of an input space, determining its orientation and, in most case, its skeleton.
Mirror-based systems are object-oriented reflective architectures built around a set of design principles that lead to reflective APIs which foster a high degree of reusability, loose coupling with base-level objects ...
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Many parallel computing applications are used for simulation of complex engineering applications and/or for visualization. To handle their complexity, there is a need for raising the level of abstraction in specifying...
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Speaker age is a speaker characteristic which is always present in speech. Previous studies have found numerous acoustic features which correlate with speaker age. However, few attempts have been made to establish the...
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Considering the large amounts of data that is nowadays produced in the biochemistry (functional genomics) it is difficult to extract the information from the measurements. There is currently also a great interest in t...
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ISBN:
(纸本)9788096956265
Considering the large amounts of data that is nowadays produced in the biochemistry (functional genomics) it is difficult to extract the information from the measurements. There is currently also a great interest in the development of novel analytical technologies for rapid screening of disease symptoms in pharmaceutical and clinical applications. Modeling and simulation can provide a useful help in understanding the relations of the measured substances and to minimize the need for measurements. The BioChem library presented here is the first free Modelica library available for mathematical modeling of biochemical processes. Three examples are shown to illustrate the library. First, a simple insulin model is presented. Then a simplified model of cholesterol together with simulations are shown. Next, a simple drug model together with parameter estimation in NONMEN are presented. The BioChem library allows for fast and end-user friendly modeling of biomedical systems. The graphical user interface provides graphics similar to that used in the description of metabolic pathways in biochemistry.
programming models based on algorithmic skeletons promise to raise the level of abstraction perceived by programmers when implementing parallel applications, while guaranteeing good performance figures. At the same ti...
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This paper describes a new solution method applied to the problem initializing DAEs using the Modelica language. Modelica is primarily an object- oriented equ-tion-based modeling language that allows specification of ...
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This paper describes a new solution method applied to the problem initializing DAEs using the Modelica language. Modelica is primarily an object- oriented equ-tion-based modeling language that allows specification of mathematical models of complex natural or man-made systems. Major features of Modelica are the multidomain modeling capability and the reusability of model components corresponding to physical objects, which allow to build and simulate highly complex systems. However, initializing such models has been quite cumbersome, since initial equations have to be pro-vided at the system level, where the user needs to know details on the underlying transformation and index-reduction algorithms, that in general are applied to simulate a Modelica model.
On-line assessment of English-Chinese translation is a challenging task as it involves natural language processing. YanFa, an on-line assessment system for English-Chinese translation, is a pilot research project into...
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On-line assessment of English-Chinese translation is a challenging task as it involves natural language processing. YanFa, an on-line assessment system for English-Chinese translation, is a pilot research project into scoring student's translation on-line. Based on the theory of translation equivalence, an algorithm called conceptual similarity matching was developed. YanFa can assess students' translation on-line timely, generate test papers automatically, offer standard versions of translation, and the scores of each sentence to students. The evaluation proves that YanFa is practical compared with the scores given by experts.
With the emerging paradigm of grid computing and the development of grid infrastructures, grid-based applications are becoming a common approach for solving many complex, large-scale problems in science and engineerin...
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With the emerging paradigm of grid computing and the development of grid infrastructures, grid-based applications are becoming a common approach for solving many complex, large-scale problems in science and engineering. In order to benefit from the large computing power of grid systems, efficient allocation of jobs to resources is necessary. In this work, we consider the allocation problem in immediate mode, in which jobs are allocated as soon as they arrive in the system. We implemented several methods and measured four parameters of the system: makespan, flow- time, resource utilization and matching proximity. The immediate methods are especially interesting when good quality allocations are necessary in very short time. The considered methods have been tested using the most difficult benchmark in the literature for the problem. The computational results allowed us to identify which of considered methods perform better for makespan, flowtime, resource utilization and matching proximity. Also, we were able to evaluate the usefulness of such methods if we knew in advance certain grid characteristics such as degree of consistency of computing, heterogeneity of jobs and resources.
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