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991.
Immune-based algorithms for dynamic optimization 总被引:4,自引:0,他引:4
The main problem with biologically inspired algorithms (like evolutionary algorithms or particle swarm optimization) when applied to dynamic optimization is to force their readiness for continuous search for new optima occurring in changing locations. Immune-based algorithm, being an instance of an algorithm that adapt by innovation seem to be a perfect candidate for continuous exploration of a search space. In this paper we describe various implementations of the immune principles and we compare these instantiations on complex environments. 相似文献
992.
993.
The factors leading to the continuing problems with information system (IS) project failure are of importance to both the research and practitioner communities. The psychological factors that lead project managers to escalate troubled projects are investigated. Theoretical grounding is presented for a research model consisting of Need for Achievement as an antecedent trait for implementation mindset, internal locus of control, preference for consistency, and time urgency, which in turn predict the Intention to Continue a troubled IS project. Using responses from 232 IS project stakeholders, the model is tested using structural equation modeling. The results support Need for Achievement as an antecedent to the other independent variables. Implementation mindset and internal locus of control were found to be significant predictors of the project managers’ intention to continue the IS projects. Based on the findings, suggestions for project re-evaluation milestones (PRMs) are presented. 相似文献
994.
Michael?DeBoleEmail author Ramakrishnan?Krishnan Varsha?Balakrishnan Wenping?Wang Hong?Luo Yu?Wang Yuan?Xie Yu?Cao N.?Vijaykrishnan 《International journal of parallel programming》2009,37(4):417-431
Degradation of device parameters over the lifetime of a system is emerging as a significant threat to system reliability.
Among the aging mechanisms, wearout resulting from Negative Bias Temperature Instability (NBTI) is of particular concern in
deep submicron technology generations. While there has been significant effort at the device and circuit level to model and
characterize the impact of NBTI, the analysis of NBTI’s impact at the architectural level is still at its infancy. To facilitate
architectural level aging analysis, a tool capable of evaluating NBTI vulnerabilities early in the design cycle has been developed
that evaluates timing degradation due to NBTI. The tool includes workload-based temperature and performance degradation analysis
across a variety of technologies and operating conditions, revealing a complex interplay between factors influencing NBTI
timing degradation. 相似文献
995.
Prof. Dr. Erwin Grochla Direktor Betriebswirtschaftliches Institut für Organisation und Automation an der Universit?t zu
K?ln K?ln Deutschland 《WIRTSCHAFTSINFORMATIK》2009,51(1):104-109
Zusammenfassung Nachdruck eines Aufsatzes aus elektronische datenverarbeitung 11(11)1969:544–548.
This article is also available in English via and : Grochla E (2008) Corporate Information Systems Engineering and Business and Information Systems Engineering as a Necessary
Application-Oriented Extension of General Computer Science – Proposals for Enhancing Academic Education in the Field of Automated
Data Processing in the Federal Republic of Germany. Bus Inf Syst Eng. doi .
相似文献
相似文献
996.
The Bazanski approach to deriving paths is applied to Finsler geometry. The approach is generalized and applied to a new developed geometry called “Absolute parallelism with Finslerian Flavor” (FAP). A set of path equations is derived for the FAP. It is a horizontal (h) set. A striking feature in this set is that the coefficient of the torsion term jumps by a step of one-half from one equation to the other. It is tempting to believe that the h-set admits some quantum features. Comparisons with the corresponding sets in other geometries are given. Conditions for reducing the set of path equations obtained to well-known path equations in some geometries are summarized in a schematic diagram. 相似文献
997.
This paper presents a new method for Internet-based control of linear automation systems by combining the predictive control and the variable sampling period strategies. In this way, event driven sensors are implemented and the sensors are triggered to sample the outputs of the plant, when new control input signals are received by the actuators. Therefore, at each sampling instant, total control loop delay will be equal to the sampling period which is unknown. In order to deal with Internet effects, associated with a range of pre-specified time delays, appropriate zero-order hold discrete-time models of the Internet-based plant are calculated off-line, and based on them, some stabilizing control signals are constructed on-line. This control signals are then packed in the control-side packet, transmitted back to the plant-side and received by a time delay compensator module. According to the actually occurred time delay in the loop, this module selects a single entry of the received control vector for each actuator, and applies them to the plant, through zero-order hold elements. Simultaneously, the sensors are triggered to measure the new plant data, the plant-side packet is assembled and transmitted to the control-side. The above procedure is then repeated from start. A less conservative switched quadratic Lyapunov is used here for stabilizing controller design. Simulation studies on well-known benchmark problems demonstrate the effectiveness of the proposed method. 相似文献
998.
Jesus?BrialesEmail authorView authors OrcID profile Javier?Gonzalez-Jimenez 《Journal of Mathematical Imaging and Vision》2016,55(3):266-283
We provide a simple closed-form solution to the Perspective three orthogonal angles (P3oA) problem: given the projection of three orthogonal lines in a calibrated camera, find their 3D directions. Upon this solution, an algorithm for the estimation of the camera relative rotation between two frames is proposed. The key idea is to detect triplets of orthogonal lines in a hypothesize-and-test framework and use all of them to compute the camera rotation in a robust way. This approach is suitable for human-made environments where numerous groups of orthogonal lines exist. We evaluate the numerical stability of the P3oA solution and the estimation of the relative rotation with synthetic and real data, comparing our results to other state-of-the-art approaches. 相似文献
999.
K.?Chen E.?Loli?PiccolominiEmail author F.?Zama 《Journal of Mathematical Imaging and Vision》2016,54(2):240-255
In this paper, we consider the problem of restoring blurred noisy vectorial images where the blurring model involves contributions from the different image channels (cross-channel blur). The proposed method restores the images by solving a sequence of quadratic constrained minimization problems where the constraint is automatically adapted to improve the quality of the restored images. In the present case, the constraint is the Total Variation extended to vectorial images, and the objective function is the \(\ell _2\) norm of the residual. After proving the convergence of the iterative method, we report the results obtained on a wide set of test images, showing that this approach is efficient for recovering nearly optimal results. 相似文献
1000.
In this paper we perform Infinitesimal Perturbation Analysis (IPA) for a single-stage stochastic fluid queue that is shared between two competing sources, one that employs additive loss-feedback congestion control and the other that employs no congestion-control (i.e., it is unresponsive). This scenario is applicable within the realm of computer communication networks particularly at bottleneck router queues where multiple and diverse flows compete for bandwidth. We optimize the tradeoff between total loss volume and queue workload (a measure for queueing delay). Although a sound knowledge of the system’s dynamics is required to derive the IPA gradient estimators, no knowledge of the underlying probability distributions governing the system is required. What results are fairly simple counting processes, whose values can be computed directly from an ongoing live stream of traffic. 相似文献