考虑搬运车辆空载的多行设备布局设计

对于多行设备布局问题,通过对搬运车辆运行情况的分析,建立的模型中以搬运设备的重载运行和空载运行的费用之和最小作为目标函数,设计了相应的遗传算法来求解。通过一个实例进行了模拟计算,进一步与原有模型的仿真结果进行了比较。比较结果说明了利用该模型得到的设备布置方案要优于采用原有模型得到的布置方案。     

A modified simple heuristic for the p-median problem, with facilities design applications

Facilities design is closely related to efficient use of available resources. This paper presents a heuristic approach to solve two core problems of a good facilities design: facility location and facility layout. The latter group of problems will be solved for warehouse and production systems in particular. All these problems can be formulated as p-median clustering problems. Teitz and Bart (Oper. Res. 16 (1968) 955–961) developed the vertex substitution method to solve those problems. This paper introduces effective improvements on this heuristic. The approach is tested on a large number of randomly generated cases and on problems taken from the literature. The results demonstrate the effectiveness and superiority of our method.     

Combined computer-aided approach for the facilities design problem and estimation of the distribution parameter in the case of multigoal optimization

The multigoal facilities design problem, a case of quadratic assignment problem, deals with the problem of optimum assignment of n facilities to n locations, optimizing multigoal cost objectives. These objectives are classified into two categories, conflicting and congruent. Conflicting objectives aim at minimization of total flow cost and maximization of total closeness rating, whereas congruent objectives aim at maximization of distance weighted cost of several attributes, vis. flow, closeness rating, etc. The technique available for dealing with the congruent objective optimization does not consider the weightage to these attributes. The optimality of a suboptimal solution should also be checked at all levels of weightages in order to arrive at a correct solution, with the help of estimation of the distribution parameter, in the case of the multigoal facilities design problem.

This paper presents a combined computer-aided approach which determines the solution of the multigoal facilities design problem at different weightages to attributes, finds the parameter of distribution viz. mean, median, mode, standard deviation, checks the optimality of solution, plots the histogram and gives the nature of distribution.     

Graphics facilities for computer-aided architectural design

An account is given of the graphics facilities developed by ABACUS for use on an inexpensive storage tube display terminal connected to a timesharing computer. The facilities allow programs to display simple pictures and menus of commands on the terminal as well as to manipulate graphically the geometrcal information common to many schematic design problems found in architecture.     

On the design of compensator for quantization-caused input-output deviation

This paper considers the design of compensators for systems with quantized inputs in order to reduce the influence of quantization.For systems with (vector) relative degrees,we propose a kind of compensators which can compensate for the accumulated output deviation completely caused by quantization.The proposed compensators are capable of keeping the differences of the input-output responses between the systems with quantized inputs and the original systems without considering quantization within certain sm...     

A microcomputer database system for facilities design

A data base management system which is dedicated to plant layout type data, and should be useful to the practicing industrial engineer, is presented. The data items utilized in the data base for this microcomputer software represent only a minimal subset of the data which one would want for the creation of a proper, industrial facility design; however, they were felt to represent a good starting point for the creation of a microcomputer data base system which would aid a layout engineer. The Knowledgeman software (Micro Data Base Systems, Inc.) was used for this project; it consists of a relational database and an electronic spreadsheet. Two plant layout examples are presented to demonstrate the use of the software.     

An EWMA chart for monitoring the process standard deviation when parameters are estimated

The EWMA chart for the standard deviation is a useful tool for monitoring the variability of a process quality characteristic. The performance of this chart is usually evaluated under the assumption of known parameters. However, in practice, process parameters are estimated from an in-control Phase I data set. A modified EWMA control chart is proposed for monitoring the standard deviation when the parameters are estimated. The Run Length properties of this chart are studied and its performance is evaluated by comparing it with the same chart but with process parameters assumed known.     

方向对比度和区域标准差相结合的图像融合

小波变换的图像融合方法已成为现今研究的一个热点。但几乎所有的算法都是在小波域不同尺度上分别对高频系数和低频系数进行融合,没有考虑到它们之间固有的相关性。为此,提出了一种基于方向对比度和区域标准差最大的融合新算法,主要特点是在低频部分采用加权因子自适应调节参数融合,以减少边缘模糊,对于高频部分采用方向对比度和局部区域窗口标准差最大值作为高频分量,突出对比度和局域细节,实验表明：融合后影像信息量丰富,地物轮廓清晰可辨,对比度大大加强,空间分辨率得到了提高,最大限度保留了原始影像的光谱信息,是一种可行有效的融合方法。     

Mean analysis of an online algorithm for the vertex cover problem

In 2005, Demange and Paschos proposed in [M. Demange, V.Th. Paschos, On-line vertex-covering, Theoret. Comput. Sci. 332 (2005) 83-108] an online algorithm (noted LR here) for the classical vertex cover problem. They shown that, for any graph of maximum degree Δ, LR constructs a vertex cover whose size is at most Δ times the optimal one (this bound is tight in the worst case).Very recently, two of the present authors have shown in [F. Delbot, C. Laforest, A better list heuristic for vertex cover, Inform. Process. Lett. 107 (2008) 125-127] that LR has interesting properties (it is a good “list algorithm” and it can easily be distributed). In addition, LR has good experimental behavior in spite of its Δ approximation (or competitive) ratio and the fact that it can be executed without the knowledge of the full instance at the beginning.In this paper we analyze it deeper and we show that LR has good “average” performances: we prove that its mean approximation ratio is strictly less than 2 for any graph and is equal to 1+e−2≈1.13 in paths. LR is then a very interesting algorithm for constructing small vertex covers, despite its bad worst case behavior.     

基于局部均值和标准差的图像去雾算法

针对雾天图像对比度低和颜色退化严重现象,提出一种单幅图像快速去雾算法。对雾天图像局部区域均值和标准差的特点进行分析,根据图像局部均值和标准差的差值得到关于大气散射光的估计,结合大气散射模型对雾天图像进行修复。实验结果表明,算法能够有效地去除图像中的雾气,且处理速度较快,便于实时应用。     

Analysis and design for a standard transport protocol

In the development of computer networks, the trend towards open systems interconnection is creating the need for standard protocols. The transport level protocols published by ECMA and ISO are supported by the Department of Industry as ‘intercept’ standards to be adopted by the computing community as a whole. This paper presents the published standards interpreted as a set of state transition diagrams. This reinterpretation is a necessary prerequisite to the method of implementation which is based on a finite state automaton. We summarize the advantages of a software ‘funnel machine’ to effect the state transitions during the execution of the transport protocol server. The same analysis and design technique has been used successfully to implement network and link protocol handlers. We recommend its adoption on a variety of machines in any programming language to ensure a relatively short development period and to achieve compatability among the different classes: 0, 1, 2, 3 and 4, of the transport protocol.     

Automatic computation of speckle standard deviation in SAR images

Being a coherent reception system, Synthetic Aperture Radar (SAR) sensors are highly liable to speckle noise effect, which masks details and patterns in the image, and therefore, degrades interpretation. Speckling may be reduced by applying filtering techniques to SAR multilook images. The major problem that arises from this type of method is the estimation of input parameters: sliding window size and speckle standard deviation. The present paper describes a manual and two automatic methods devised to estimate speckle standard deviation based on the texture concept, in order to extract homogenous regions. The automatic method were specially developed to improve results obtained with the manual one, and the so-called least-squares approach and mean approach were considered. The mean approach was introduced as an alternative to the least-squares approach. It performs better in terms of computing time and disk space use, and even shows a slightly higher accuracy when tested against artificially speckled images. Manual and automatic methods were applied as an example using ERS-1/SAR one-look and three-look images with different features, obtained over several Austral and Antartic regions of Argentina. Results show that the automatic method is a valuable tool for estimating speckle standard deviation, being accurate, less tedious, and preventing typical human errors associated with manual tasks.     

基于局部标准差和方向微分的模糊方向识别

针对最小方向微分算法在运动模糊方向识别中误差大和实时性差的缺点,提出利用局部标准差和方向微分相结合的方法鉴定模糊方向。该方法首先对模糊图像进行局部标准差滤波以增强模糊方向上的纹理细节,然后利用双线性插值求最小方向微分和,其对应的方向即为模糊方向;在对方向微分和曲线归纳分析后找到了其内在规律,基于此规律提出范围对半递减搜索最小值的方法,减少了搜索次数。实验结果表明该算法识别精度高,抗干扰性强,实时性好。     

Solution of the facilities layout problem by simulated annealing

The simulated annealing method (SAM) is a radically new and powerful approach to solving certain integer optimization problems. The paper describes its application to the facility layout problem (QAP) and shows how it can generally match or produce superior solutions to the best known values for classical benchmark problems. The technique is also suited to microcomputer solution using interactive graphics for practical layout problems.     

A parallel ordering problem in facilities layout

In this paper, we study a problem that occurs in the row layout of facilities. Among n facilities, suppose that there are t   facilities with some characteristic in common so that they should be arranged along one row, leaving the remainder (n−t$n-t$) facilities to be arranged on a parallel row. The objective is to order the facilities in the two rows such that some cost function is minimized. This problem is called the parallel row ordering problem (PROP). The PROP is a generalization of the single row facility layout problem (SRFLP). Here, a mixed integer programming (MIP) formulation of the PROP is presented which extends a MIP formulation of the SRFLP. We show that a PROP with n facilities may be solved faster than a SRFLP with n facilities. Theoretical and experimental comparisons of the SRFLP and the PROP formulations are presented.     

Planar expropriation problem with non-rigid rectangular facilities

In this paper, we introduce the planar expropriation problem with non-rigid rectangular facilities. The facilities considered in this study are two-dimensional facilities of rectangular shape. Moreover, we allow the facility dimensions to be decision variables and introduce the concept of non-rigid facilities. Based on the geometric properties of such facilities, we developed a new formulation for this continuous covering location model which does not require employing distance measures. This model is intended to determine the location and formation of facilities simultaneously. For solving this new model, we proposed a continuous branch-and-bound framework utilizing linear approximations for the tradeoff curve associated with the facility formation alternatives. Further, we developed new problem generation and bounding strategies suitable for our particular problem structure. Computational experience shows that the branch-and-bound procedure we developed performs better than conventional mixed-integer nonlinear programming solvers BARON and SBB for solving this particular location model.     

A stochastic estimation problem at aeromagnetometer deviation compensation

A formulation of the problem of magnitometer deviation compensation occurring at aeromagnetic survey is considered in the form of a standard stochastic estimation problem. A specific feature of this approach is the introduction of the model of a geomagnetic field anomaly. The parameters of the stochastic model are selected basing on spectral and variance analysis of the aeromagnetic survey data. Normalization of the problem parameters is made; this makes it possible to estimate the accuracy of compensation and conduct a necessary decomposition. The posed stochastic estimation problem is solved by the method of Kalman filtering.     

应用DCT块标准差的自适应隐写算法

目的为提高隐写方案的安全性,提出一种基于DCT(discrete cosine transform)块标准差的JPEG图像自适应隐写算法。方法 DCT块标准差可以反映图像各区域的复杂情况,为此根据取整失真、量化步长以及标准差设计了失真函数,然后结合STC(syndrome-trellis code)编码设计了隐写算法。结果引入DCT块标准差可使失真函数定义更合理,因此图像经隐写后总体失真减小,安全性能得到提高。结论实验结果表明,本文算法与其他同类算法相比具有更强的抵抗隐写检测能力,在质量因子为75时安全容量可达到0.35(嵌入总量和非零AC(交流)DCT系数个数之比)。     

Random fuzzy mean-absolute deviation models for portfolio optimization problem with hybrid uncertainty

Absolute deviation is a commonly used risk measure, which has attracted more attentions in portfolio optimization. The existing mean-absolute deviation models are devoted to either stochastic portfolio optimization or fuzzy one. However, practical investment decision problems often involve the mixture of randomness and fuzziness such as stochastic returns with fuzzy information. Thus it is necessary to model portfolio selection problem in such a hybrid uncertain environment. In this paper, we employ random fuzzy variable to describe the stochastic return on individual security with ambiguous information. We first define the absolute deviation of random fuzzy variable and then employ it as risk measure to formulate mean-absolute deviation portfolio optimization models. To find the optimal portfolio, we design random fuzzy simulation and simulation-based genetic algorithm to solve the proposed models. Finally, a numerical example for synthetic data is presented to illustrate the validity of the method.     

Scenarios and the HCI-SE design problem

Diaper's critical review of Carrol's book ‘Making Use’ raises a number of interesting issues about how to set about the design of interactive systems. In particular Diaper poses an issue that has long dogged the area of Human–Computer Interaction and Software Engineering (HCI-SE), namely how to deal with the formality required by the SE side and the sensitivity to context required by the HCI side. In this paper, we report on the experience of using scenario-based design and reflect on the effectiveness of the approach. This work fits into a broader context concerned with understanding exactly what the HCI-SE design problem is and now it might be best conceptualised.