High mass-resolving power has been shown to be useful for studying the conformational dynamics of proteins by hydrogen/deuterium (H/D) exchange. A computer algorithm was developed that automatically identifies peptide...
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High mass-resolving power has been shown to be useful for studying the conformational dynamics of proteins by hydrogen/deuterium (H/D) exchange. A computer algorithm was developed that automatically identifies peptides and their extent of deuterium incorporation from H/D exchange mass spectra of enzymatic digests or fragment ions produced by collisionally induced dissociation (CID) or electron capture dissociation (ECD). The computer algorithm compares measured and calculated isotopic distributions and uses a fast calculation of isotopic distributions using the fast Fourier transform (FFT). The algorithm facilitates rapid and automated analysis of H/D exchange mass spectra suitable for high-throughput approaches to the study of peptide and protein structures. The algorithm also makes the identification independent on comparisons with undeuterated control samples. The applicability of the algorithm was demonstrated on simulated isotopic distributions as well as on experimental data, such as Fourier transform ion cyclotron resonance (FTICR) mass spectra of myoglobin peptic digests, and CID and ECD spectra of substance P. (C) 2001 American Society for Mass Spectrometry.
We present JAPE, a flexible prototyping system to support the design of a new advanced collaborative virtual environment. We describe the utilization of different hard- and software components to quickly build a flexi...
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We present JAPE, a flexible prototyping system to support the design of a new advanced collaborative virtual environment. We describe the utilization of different hard- and software components to quickly build a flexible, yet powerful test bed for application and algorithm development. These components include a 3-D rendering toolkit, live video acquisition, speech transmission, and the control of tracking and interaction devices. To facilitate the simultaneous design of applications and algorithms that take advantage of unique features of new collaborative virtual environments, we provide the developer with a flexible prototyping toolkit which emulates the functionality of the final system. The applicability of JAPE is demonstrated with several prototype applications and algorithms.
A command sequence replanning and control method, which enables the slave system to autonomously recover from error conditions, is proposed in a telerobot system. A task model described as a form of the controlled Pet...
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A command sequence replanning and control method, which enables the slave system to autonomously recover from error conditions, is proposed in a telerobot system. A task model described as a form of the controlled Petri net (CPN) is used as a prior knowledge for the slave system to carry out the given task successfully without the operator's aid even in unexpected error conditions. The CPN model incorporates the contact states and transitional motions between them that possibly exist in the task execution process. The motion command is automatically generated from the master system and transmitted to the slave whenever the contact state changes in the master model. Referring to the CPN model and the given motion commands, the slave system detects if the actual contact state is unexpected and then plans the recovery path from the unexpected state. The feasibility of the command sequence replanning and control algorithm is verified through an example to perform a simple part-mating task. (C) 2001 John Wiley & Sons, Inc.
This paper presents an exact algorithm for the single machine total tardiness problem (1//SigmaT(i)). We present a new synthesis of various results from the literature which leads to a compact and concise representati...
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This paper presents an exact algorithm for the single machine total tardiness problem (1//SigmaT(i)). We present a new synthesis of various results from the literature which leads to a compact and concise representation of job precedences, a simple optimality check, new decomposition theory, a new lower bound, and a check for presolved subproblems. These are integrated through the use of an equivalence concept that permits a continuous reformation of the data to permit early detection of optimality at the nodes of an enumeration tree. The overall effect is a significant reduction in the size of the search tree, CPU times, and storage requirements. The algorithm is capable of handling much larger problems (e.g., 500 jobs) than its predecessors in the literature (less than or equal to 150). In addition, a simple modification of the algorithm gives a new heuristic which significantly outperforms the best known heuristics in the literature.
Genetic programming (GP) usually has a wide search space and a high flexibility. Therefore, GP may search for global optimum solution. But, in general, GPs learning speed is not so fast. An apriori algorithm is one of...
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Genetic programming (GP) usually has a wide search space and a high flexibility. Therefore, GP may search for global optimum solution. But, in general, GPs learning speed is not so fast. An apriori algorithm is one of association rule algorithms. It can be applied to a large database. But it is difficult to define its parameters without experience. We propose a rule generation technique from a database using GP combined with an association rule algorithm. It takes rules generated by the association rule algorithm as initial individual of GP. The learning speed of GP is improved by the combined algorithm. To verify the effectiveness of the proposed method, we apply it to the decision tree construction problem from the University of California at Irvine (UCI) machine-learning repository, and rule disco very problem from the occurrence of the hypertension database. We compare the results of the proposed method with prior ones.
作者：
Samareh, JANASA
Langley Res Ctr Multidisciplinary Optimizat Branch Hampton VA 23665 USA
A multidisciplinary shape parameterization approach is presented. The approach consists of two basic concepts: 1) parameterizing the shape perturbations rather than the geometry itself and 2) performing the shape defo...
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A multidisciplinary shape parameterization approach is presented. The approach consists of two basic concepts: 1) parameterizing the shape perturbations rather than the geometry itself and 2) performing the shape deformation by means of the soft object animation algorithms used in computer graphics. Because the formulation presented is independent of grid topology, we can treat computational fluid dynamics and finite element grids in the same manner. The proposed approach is simple, compact, and efficient. Also, the analytical sensitivity derivatives are easily computed for use in a gradient-based optimization. This algorithm is suitable for low-fidelity, for example, linear aerodynamics and equivalent laminated plate structures, and high-fidelity, for example, nonlinear computational fluid dynamics and detailed finite element modeling, analysis tools. The implementation details of parameterizing for planform, twist, dihedral, thickness, camber, and free-form surface are given. Results are presented for a multidisciplinary application consisting of nonlinear computational fluid dynamics, detailed computational structural mechanics, and a simple performance module.
THE CHOKE ROUTER ALGORITHM PROVIDES AN APPROXIMATELY FAIR BANDWIDTH ALLOCATION AT A LOW IMPLEMENTATION COST. THE AUTHORS CONSIDER PERFORMANCE AND IMPLEMENTATION ISSUES ASSOCIATED WITH CHOKE, WITH PARTICULAR EMPHASIS O...
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THE CHOKE ROUTER ALGORITHM PROVIDES AN APPROXIMATELY FAIR BANDWIDTH ALLOCATION AT A LOW IMPLEMENTATION COST. THE AUTHORS CONSIDER PERFORMANCE AND IMPLEMENTATION ISSUES ASSOCIATED WITH CHOKE, WITH PARTICULAR EMPHASIS ON VARIABLE-LENGTH PACKETS.
External memory (EM) algorithms are designed for computational problems in which the size of the internal memory of the computer is only a small fraction of the problem size. Blockwise access to data is a central them...
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External memory (EM) algorithms are designed for computational problems in which the size of the internal memory of the computer is only a small fraction of the problem size. Blockwise access to data is a central theme in the design of efficient EM algorithms, A similar requirement arises in the transmission of data between processors in high performance parallel computation systems, for which blockwise communication is a crucial issue. We consider multisearch problems, where a large number of queries are to be simultaneously processed and satisfied by navigating through large data structures on parallel computers, Our examples originate as algorithms for parallel machines, and we adapt them to the EM situation where the queries and data structure are considered to be much larger than the size of the available internal memory. This paper presents techniques to achieve blocking for I/O as well as for communication in multisearch on the BSP and EM-BSP models. We describe improvements to the 1-optimal BSP* multisearch algorithm of [8] which permit larger search trees to be handled. In the area of EM algorithms new algorithms for multisearch in balanced trees are described. For search trees of size O (n log n) where n is the number of queries, we obtain a work-optimal, parallel, randomized EM multisearch algorithm whose I/O and communication time are smaller, asymptotically, than the computation time. We obtain a deterministic version via a similar technique. These algorithms are obtained via the simulation techniques of [12], [17], [13], [14], and [24]. For larger trees we describe a parallel, EM algorithm which is I-optimal considering computation, communication, and I/O (for suitable parameter constellations) plus I/O-optimal. We give a lower bound to the number of I/O operations required for filtering n queries through a binary or multiway search tree of size m when m greater than or equal to n(2 + epsilon) for a constant epsilon > 0.
In this paper we analyze the limiting behavior of several randomized work stealing algorithms in a dynamic setting. Our models represent the limiting behavior of systems as the number of processors grows to infinity u...
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In this paper we analyze the limiting behavior of several randomized work stealing algorithms in a dynamic setting. Our models represent the limiting behavior of systems as the number of processors grows to infinity using differential equations. The advantages of this approach include the ability to model a large variety of systems and to provide accurate numerical approximations of system behavior even when the number of processors is relatively small. We show how this approach can yield significant intuition about the behavior of work stealing algorithms in realistic settings.
This paper describes the experimental comparison among four model-based control algorithms on a direct-drive robotic arm. We present experimental results of the following controllers: Computed-Torque control, PD + con...
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This paper describes the experimental comparison among four model-based control algorithms on a direct-drive robotic arm. We present experimental results of the following controllers: Computed-Torque control, PD + control, PD control with computed feedforward and PD control. All controllers include Coulomb and viscous friction compensation as well as cancellation of gravitational torques. They are tested under common trajectory specification and performance index. (C) 2000 Elsevier Science Ltd. All rights reserved.
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