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1.
In a recent paper, Alidaee [Computers ind. Engng 24, 53–55 (1993)] notes the similarity between the scheduling problems of minimizing weighted mean flow time (WMFT) on two parallel machines and minimmizing weighted earliness/tardiness (WET) about a common due date on a single machine. Based on this similarity, Alidaee descirbes how a dynamic programming algorithm proposed by Hall and Posner [Opns Res. 39, 836–846 (1991)] for the WET problem can be modified and applied to the WMFT problem. The work is an important extension of earlier results on an equivalence relationship between the WMFT and WET problems. This Note helps consolidate the literature by recognizing Rothkopf [Mgmt Sci. 12, 437–447 (1966)] as the originator of algorithm described in [Computers ind. Engng 24 53–55 (1993)].  相似文献   

2.
Timing Closure in presence of long global wire interconnects is one of the main current issues in System-on-Chip design. One proposed solution to the Timing Closure problem is Latency-Insensitive Design (LID) [Luca Carloni, Kenneth McMillan, and Alberto Sangiovanni-Vincentelli. Theory of latency-insensitive design. IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems, vol. 20(no. 9):pp. 1059–1076, 2001; Mario R. Casu and Luca Macchiarulo. A new approach to latency insensitive design. In DAC'04: Proceedings of the 41st annual conference on Design automation, pages 576–581, New York, NY, USA, 2004. ACM Press].It was noticed in [Mario R. Casu and Luca Macchiarulo. A new approach to latency insensitive design. In DAC '04: Proceedings of the 41st annual conference on Design automation, pages 576–581, New York, NY, USA, 2004. ACM Press] that, in many cases, the dynamically scheduled synchronisations introduced by latency-insensitive protocols could be computed off-line as a static periodic schedule. We showed in [Julien Boucaron, Jean-Vivien Millo, and Robert De Simone. Latency-insensitive design and central repetitive scheduling. In Formal Methods and Models for Co-Design, 2006. MEMOCODE'06. Proceedings. Fourth ACM and IEEE International Conference on, pages 175–183, Piscataway, NJ, USA, 2006. IEEE Press; Julien Boucaron, Jean-Vivien Millo, and Robert De Simone. Formal methods of scheduling for latency-insensitive designs. EURASIP journal on embedded system, 2007 (not yet published)] how this schedule could then be used to further optimize the protocol resources when they are found redundant. The purpose of the present paper is to study how the larger blocks, obtained as synchronous components interconnected by LID protocols optimized by static schedule informations, can be again made to operate with an environment that provides also I/O connections at its own (synchronous or GALS) rate.We also consider the case of multirate SoC, using results from SDF (Synchronous DataFlow) theory [Edward A. Lee and David G. Messerschmitt. Synchronous data flow. Proceeding of the IEEE, vol. 75(no. 9):pp. 1235–1245, 1987].  相似文献   

3.
We present the new Water Ecosystems Tool (WET), a workflow implemented (as a plugin) in QGIS, for application and evaluation of aquatic ecosystem models. WET provides a Graphical User Interface (GUI) for the coupled one-dimensional hydrodynamic-ecosystem model GOTM-FABM-PCLake. WET is unique as it enables a standardized and easy-to-use workflow for an otherwise complex model application and is readily applicable to any individual lake and reservoir in the world. WET integrates a platform for model experimentation through scenario simulations – currently encompassing changes in climate and nutrient loads. WET also includes a link to the SWAT (Soil & Water Assessment Tool) watershed model, which can be used to simulate how land use changes affect aquatic ecosystems. The tool is open source and may therefore be readily expanded and adapted for additional model experimentations.  相似文献   

4.
The adaptive multistep linear and nonlinear filters for multiscale shock/turbulence gas dynamics and magnetohydrodynamics (MHD) flows of the authors are extended to include compact high order central differencing as the spatial base scheme. The adaptive mechanism makes used of multiresolution wavelet decomposition of the computed flow data as sensors for numerical dissipative control. The objective is to expand the work initiated in [Yee HC, Sjögreen B. Nonlinear filtering in compact high order schemes. In: Proceedings of the 19th ICNSP and 7th APPTC conference; 2005; J Plasma Phys 2006;72:833–36] and compare the performance of adaptive multistep filtering in compact high order schemes with adaptive filtering in standard central (non-compact) schemes for multiscale problems containing shock waves.  相似文献   

5.
Web data being transmitted over a network channel on the Internet with excessive amount of data causes data processing problems, which include selectively choosing useful information to be retained for various data applications. In this paper, we present an approach for filtering less-informative attribute data from a source Website. A scheme for filtering attributes, instead of tuples (records), from a Website becomes imperative, since filtering a complete tuple would lead to filtering some informative, as well as less-informative, attribute data in the tuple. Since filtered data at the source Website may be of interest to the user at the destination Website, we design a data recovery approach that maintains the minimal amount of information for data recovery purpose while imposing minimal overhead for data recovery at the source Website. Our data filtering and recovery approach (1) handles a wide range of Web data in different application domains (such as weather, stock exchanges, Internet traffic, etc.), (2) is dynamic in nature, since each filtering scheme adjusts the amount of data to be filtered as needed, and (3) is adaptive, which is appealing in an ever-changing Internet environment.  相似文献   

6.
为了使SCARA机器人在外界干扰和模型不精确的情况下具有优良的轨迹跟踪性能,提出一种基于内模控制原理设计SCARA机器人控制器的方法。采用拉格朗日方法获得SCARA机器人动力学模型,将其作为内模控制的估计模型;选择内模滤波器[f(S)]设计内模控制器[Q(S),]使其满足稳态误差为零的条件,通过推导得出不同输入信号下的SCARA机器人控制律。通过仿真,将其与自适应模糊滑模控制方法进行对比分析,结果表明所提出的方法轨迹跟踪精度高,抗干扰能力强,控制器参数调节简单。  相似文献   

7.
针对目标检测模型在训练过程中正负样本分配时没有考虑真实框的长宽比、对物体不同分布的适应能力差等不足,提出了比例先验和损失感知的分配算法RLA。RLA不改变原有检测模型的结构,首先根据真实框的长宽比选择等比例的中心区域,然后计算锚点综合损失,考虑真实框内物体的实际分布,最后通过动态损失阈值的方式区分正负样本。该算法解决了基于IoU分配时适应性差、难以选出最佳正样本等问题,对偏心物体和长宽比悬殊物体的样本分配更加合理。与已有的样本分配算法对比,该算法在MS COCO数据集上的表现更优,比基线FCOS的AP提升1.66%;在模型结构相同时,比ATSS和PAA算法的AP分别提升了0.76%和0.24%,证明了RLA算法的有效性。  相似文献   

8.
在线鲁棒最小二乘支持向量机回归建模   总被引:5,自引:0,他引:5  
鉴于工业过程的时变特性以及现场采集的数据通常具有非线性特性且包含离群点,利用最小二乘支持向量机回归(least squares support vector regression,LSSVR)建模易受离群点的影响.针对这一问题,结合鲁棒学习算法(robust learning algorithm,RLA),本文提出了一种在线鲁棒最小二乘支持向量机回归建模方法.该方法首先利用LSSVR模型对过程输出进行预测,与真实输出相比较得到预测误差;然后利用RLA方法训练LSSVR模型的权值,建立鲁棒LSSVR模型;最后应用增量学习方法在线更新鲁棒LSSVR模型,从而得到在线鲁棒LSSVR模型.仿真研究验证了所提方法的有效性.  相似文献   

9.
The interplay between recent results and methodologies in numerical linear algebra and mathematical software and their application to problems arising in systems, control, and estimation theory is discussed. The impact of finite precision, finite range arithmetic [including the implications of the proposed IEEE floating point standard(s)] on control design computations is illustrated with numerous examples as are pertinent remarks concerning numerical stability and conditioning. Basic tools from numerical linear algebra such as linear equations, linear least squares, eigenproblems, generalized eigenproblems, and singular value decomposition are then outlined. A selected list of applications of the basic tools then follows including algorithms for solution of problems such as matrix exponentials, frequency response, system balancing, and matrix Riccati equations. The implementation of such algorithms as robust mathematical software is then discussed. A number of issues are addressed including characteristics of reliable mathematical software, availability and evaluation, language implications (Fortran, Ada, etc.), and the overall role of mathematical software as a component of computer-aided control system design.  相似文献   

10.
As more organizations grasp the tremendous benefits of Mobile Ad-hoc Networks (MANETs) in tactical situations such as disaster recovery or battlefields, research has begun to focus on ways to secure such environments. Unfortunately, the very factors that make MANETs effective (fluidity, resilience, and decentralization) pose tremendous challenges for those tasked with securing such environments. Our prior work in the field led to the design of BITSI – the Biologically-Inspired Tactical Security Infrastructure. BITSI implements a simple artificial immune system based upon Danger Theory. This approach moves beyond self/non-self recognition and instead focuses on systemic damage in the form of deviation from mission parameters. In this paper, we briefly review our prior work on BITSI and our simulation environment, and then present the application of collaborative filtering techniques. Our results are encouraging, and show that collaborative filtering significantly improves classification error rate and response within the MANET environment. Finally, we explore the implications of the results for further work in the field, and describe our plans for new research.  相似文献   

11.
This paper presents the mathematical formulation and design methodology of progressive filtering (PF) for multimedia information retrieval, and discusses its application to the so-called query by singing/humming (QBSH), or more formally, melody recognition. The concept of PF and the corresponding dynamic programming-based design method are applicable to large multimedia retrieval systems for striking a balance between efficiency (in terms of response time) and effectiveness (in terms of recognition rate). The application of the proposed PF to a five-stage QBSH system is reported, and the experimental results demonstrate the feasibility of the proposed approach.  相似文献   

12.
《Applied Soft Computing》2008,8(1):809-819
This paper presents a neuro-genetic approach proposed to suggest the process parameters for maintaining the desired depth of cut in abrasive waterjet (AWJ) cutting by considering the change in diameter of focusing nozzle, i.e. for adaptive control of AWJ cutting process. An artificial neural network (ANN) based model is developed for prediction of depth of cut by considering the diameter of focusing nozzle along with the controllable process parameters such as water pressure, abrasive flow rate, jet traverse rate. ANN model combined with genetic algorithm (GA), i.e. neuro-genetic approach, is proposed to suggest the process parameters. Further, the merits of the proposed approach is shown by comparing the results obtained with the proposed approach to the results obtained with fuzzy-genetic approach [P.S. Chakravarthy, N. Ramesh Babu, A hybrid approach for selection of optimal process parameters in abrasive water jet cutting, Proceedings of the Institution of Mechanical Engineers, Part B: J. Eng. Manuf. 214 (2000) 781–791]. Finally, the effectiveness of the proposed approach is assessed by conducting the experiments with the suggested process parameters and comparing them with the desired results.  相似文献   

13.
针对网络化控制系统的滤波器参数存在摄动的问题,考虑到传感器-滤波器存在随机时延和丢包,设计对系统待估信号进行估计的加性非脆弱耗散滤波器,其中滤波器参数具有范数有界不确定性。首先使用Lyapunov稳定性理论和线性矩阵不等式分析方法,推导出耗散滤波器存在的充分条件,在此基础上考虑到滤波器参数不确定性,从而将非脆弱耗散滤波问题转化为求解线性矩阵不等式的问题,然后通过求解线性矩阵不等式得到非脆弱耗散滤波器的参数表达式,最后数值仿真验证了设计方法的有效性。  相似文献   

14.
Real-time media streams with (m,k)-firm are increasing and attractive as it proposes an alternative quality of service (QoS). In order to meet these ever increasing demands, the problem of scalability should be considered under limited resource. The problem is ignored in the existing solutions all along, because these solutions maintain a separate queue for each stream and per-stream state information. In this paper, we extend the work made in[Ji Ming Chen, Zhi Wang, Ye Qiong Song, and You Xian Sun. A scalable approach for streams with (m,k)-firm deadline. In Proceedings of IEEE Workshop on Quality of Service for Application Servers (2004 October)] and propose loss-rate balance (static) and stream number balance (dynamic) Class Selection Algorithm (CSA) for real-time media streams with (m,k)-firm, which is scalable while offering dynamic performance close to that of existing solutions. The effectiveness of static CSA (S-CSA) that captures the trade-off between scalability and QoS granularity is evaluated through extensive simulation studies. It is also shown that the S-CSA is as effective to guarantee QoS in terms of dynamic failure rate as the dynamic one.  相似文献   

15.
针对工业变频、交流伺服等市场领域对功率模块的需求,三菱公司开发了第5代IPM智能功率模块.该文简述了IPM模块的基本工作特性,然后以L系列IPM25RLA120模块为例,详细介绍了IPM模块外围接口电路的设计,并提出了IPM过流保护的一种设计方法.最后通过数字伺服驱动控制系统的项目实例,表明了该接口电路设计具有结构简单、抗干扰性强、运行可靠等优点.  相似文献   

16.
Multimedia streaming over the Internet has been a very challenging issue due to the dynamic uncertain nature of the channels. This paper proposes an algorithm for the joint design of source rate control and congestion control for video streaming over the Internet. With the incorporation of a virtual network buffer management mechanism (VB), the quality of service (QoS) requirements of the application can be translated into the constraints of the source rate and the sending rate. Then at the application layer, the source rate control is implemented based on the derived constraints, and at the transport layer, a QoS-aware congestion control mechanism is proposed that strives to meet the send rate constraint derived from VB, by allowing temporary violation of transport control protocol (TCP)-friendliness when necessary. Long-term TCP-friendliness, nevertheless, is preserved by introducing a rate-compensation algorithm. Simulation results show that compared with traditional source rate/congestion control algorithms, this cross-layer design approach can better support the QoS requirements of the application, and significantly improve the playback quality by reducing the overflow and underflow of the decoder buffer, and improving quality smoothness, while maintaining good long-term TCP-friendliness  相似文献   

17.
We present two complex microwave filter designs using the finite element method (FEM). A metallic cavity, loaded by low-loss dielectric plates is first optimized to obtain a high unloaded quality factor resonator. An original synthesis approach is then proposed to design a three-pole dielectric loaded cavity filter. The FEM is also applied to characterize a filter element, a dielectric resonator (DR) coupled on a whispering gallery mode (WGM) to two microstrip lines. A generalized [S] matrix is computed. Different elements are then put together to generate complex filtering responses. © 1997 John Wiley & Sons, Inc. Int J Microwave Millimeter-Wave CAE 7: 167–179, 1997.  相似文献   

18.
Adaptive digital filtering has traditionally been developed based on the minimum mean square error (MMSE) criterion and has found ever-increasing applications in communications. This paper presents an alternative adaptive filtering design based on the minimum symbol error rate (MSER) criterion for communication applications. It is shown that the MSER filtering is smarter, as it exploits the non-Gaussian distribution of filter output effectively. Consequently, it provides significant performance gain in terms of smaller symbol error over the MMSE approach. Adopting Parzen window or kernel density estimation for a probability density function, a block-data gradient adaptive MSER algorithm is derived. A stochastic gradient adaptive MSER algorithm, referred to as the least symbol error rate, is further developed for sample-by-sample adaptive implementation of the MSER filtering. Two applications, involving single-user channel equalization and beamforming assisted receiver, are included to demonstrate the effectiveness and generality of the proposed adaptive MSER filtering approach.  相似文献   

19.
Real-time license plate recognition (LPR) is an interesting but complicated research topic. Some previous works use discrete wavelet transform (DWT) to extract license plate (LP), however, most of them are not capable of dealing with complex environments such as the low-contrast source images and the dynamic-range problems. In this paper, we propose an algorithm for license plate localization (LPL) based on DWT. The LP can be extracted from different quality of source images under complex environments by using two frequency subbands. We first use the HL subband to search the features of LP and then verify the features by checking whether in the LH subband there exists a horizontal line around the feature or not. The proposed method can extract both front and back LPs of various vehicles. The experimental results show that the proposed method can achieve good LPL results with both short run-time and high accurate detection rate.  相似文献   

20.
Per Hedelin 《Automatica》1978,14(3):245-254
An alternative to continuous-time Kalman filtering is sampled digital processing. The purpose is to develop a good model for this situation and investigate the resulting performance. The error dependence on the sample rate is studied. It is found that a sample rate considerably higher than twice the half power-frequency is necessary to avoid loss of performance where zero-lag filtering is desired. Smoothing is discussed and in this context three results of major importance are found; (1) an optimal sample rate exists for each smoother (2) only a few steps of lag is necessary to approach the ideal unrealizable error (3) a considerable lower sample rate can be accepted for smoothing as compared with filtering. This finding is of interest as the corresponding ideal continuous-time smoother has been reported unstable. Finally a comparison is made with approximate models suggested in the relevant literature.  相似文献   

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