Metaheuristic algorithms for the multistage hybrid flowshop scheduling problem

We consider the multistage hybrid flowshop scheduling problem, in which each stage consists of parallel identical machines. The problem is to determine a schedule that minimizes the makespan for a given set of jobs over a finite planning horizon. Since this problem class is NP-hard in the strong sense, there seems to be no escape from appealing to heuristic procedures to achieve near-optimal solutions to real life problems. First, a series of new global lower bounds to be used to estimate the minimum makespan are derived. Then, two new metaheuristic algorithms first sequence and then allocate jobs to machines based on a particular partition of the shop. The optimization procedure is based on simulated annealing and the variable-depth search. Computational experiments show the efficiency of the proposed procedures.     

The influence of colour on visual search times in cluttered environments

Fifty subjects participated in a series of visual search tasks where the aim was to explore the influence of colour on visual search times for targets situated in a series of cluttered distractor fields. The results supported previous findings regarding the effect of colour and showed that, even in cluttered environments, certain hues helped in the reduction of search times. The findings also indicated that there were interaction effects between the colour and positioning of the targets in the distractor fields.     

The analytics of search with posted prices

Summary. This paper investigates the characteristics of the optimal posted price in the standard sequential search paradigm. Much of the intuition gleaned from the extensive sequential search literature in which the seller adopts a reservation price does not carry over to the posted price setting. For example, an increase in buyer valuations can lead to a reduction in the optimal posted price. We do, however, provide sufficient conditions on the hazard rate function h which ensure that an increase in demand induces an increase in the optimal posted price. As exhibited herein, the analysis of the posted price model depends critically upon analytical properties of h. Amongst the issues treated are the elasticity of demand, finite horizon, sale of multiple units, and competitive equilibrium. Received: October 21, 1999; revised version: March 7, 2000     

Information search behavior of Hong Kong's inbound travelers‐a comparison of business and leisure travelers

Abstract

The purpose of this study is to examine the information search behavior of Hong Kong's inbound tourists, in particular business and leisure travelers. The study clearly shows that business and leisure travelers demonstrate different information search behavior. ‘Personal experience,’ ‘Travel agency/tour company,’ ‘Airlines’ and the ‘Internet’ are most frequently relied upon by business travelers in searching for travel information, while leisure travelers prefer ‘Travel agency/tour company,’ ‘Friends or relatives,’ ‘Travel guide books,’ and ‘Personal experience.’ The study also reveals that the total number of information sources used and the length of pre‐trip planning lead‐time are significantly different between these two groups of travelers. First time travelers also have a longer pre‐trip planning lead‐time than repeat travelers. Furthermore, business and leisure travelers perceive the levels of influence of several information sources, including ‘Corporate travel departments,’ ‘Friends or relatives,’ ‘Travel guide books,’ and the ‘Internet,’ differently. These information sources were classified into five different dimensions, including ‘Media,’ ‘Neutral,’ ‘Retail,’ ‘Interpersonal,’ and ‘Personal experience.’ Analysis based on travelers' purpose for traveling and demographic information was performed. Leisure travelers perceive the level of influence of ‘Neutral’ sources as significantly higher, and those with lower household incomes perceived the level of influence of ‘Personal experience’ as lower. The results of this study will allow marketers in Hong Kong to better understand travelers’ information search behavior so that they can more effectively tailor their marketing strategies to these two major markets.     

Web-based GIS in tourism information search: Perceptions,tasks, and trip attributes

People’s strategies and choices to utilize tourism information have shifted dramatically over the years following ubiquitous access to the Internet. Despite the fact that many tourism information searches on the Internet involve geo-spatial information through WebGIS, little is known about tourists’ behavioral patterns with this media. The purpose of this study was to examine tourists’ trip situations, tasks, and perceptions toward WebGIS. An electronic survey method and multiple regression technique were used to collect and analyze data. Findings indicate that ‘usefulness’ and ‘playfulness’ were the key factors that determined the level of usage and interaction. Users showed distinct behavioral tendencies under different trip situations and task performances when searching tourism information using WebGIS.     

从百度竞价排名事件谈B2B平台的顾客风险

针对B2B平台通常采用的竞价排名运营模式，本文从买家和供应商的角度分析了竞价排名、供应商分级所带来的风险、风险成因及其本质，指出竞价排名是一种不可持续的运营模式，B2B平台需要树立顾客导向的运营模式方可实现持续的赢利。     

Optimization of postal express line network under mixed driving pattern of trucks

Details about the movement of trucks on postal express lines are investigated to improve the performances of mail distribution. A mixed driving pattern of trucks is introduced to minimize the transportation cost of a postal express line network with a service level requirement. We formulate this problem as a mixed p meeting depots location with shipment scheduling problem and build a MINLP model. A two-level tabu search procedure based on shipment grouping method is developed. Through a series of computational experiments and sensitivity analysis on different instances, some managerial insights of the network under mixed driving pattern are revealed.     

An empirical analysis of the factors raising the interest in new shopping destinations

The relationship among the factors in the rising interest in new alternatives is empirically investigated in the context of shopping destination choice behavior. The hypothetical causal relationship is that the rising interest in new alternatives requires both active information search and considerable benefit, which is supported by the results of the mixture structural equation models using a data set containing revealed shopping behaviors and attitudes toward shopping destinations in the Tokyo metropolitan area: a lower level of satisfaction with the current choice set incites external information search for all subjects; however, the benefit of adding new alternatives affects the interest in new alternatives only in the group that engages in active information search.     

一种基于区域搜索的全局运动估计与补偿算法

开展全局运动估计与补偿研究是进行动态目标检测中的基础和前提。在总结现有运动估计与补偿方法的基础上,提出一种基于图像分割区域的运动性和大小的全局运动估计与补偿算法。首先,通过建立区域搜索的全局运动模型,同时进行区域定性分割和区域大小排序;然后,根据误差最小化准则在指定的分割区域中进行线性递归搜索,利用门限准则寻找出最佳的运动估计参数;最后,根据双线性内插法获得运动位移量。实验结果比较可知,所提算法较三步搜索算法(TSS)和全局搜索算法(FSA)等传统算法具有更高的准确性(图像平移帧差)和实时性(算法运行时间),能够很好地实现运动背景的全局校正。     

随机仓库布局问题模型与算法研究

通过讨论随机条件下仓库布局问题．建立了随机仓库布局问题机会约束规划模型，并设计出基于随机模拟的禁忌搜索算法求解模型，最后利用算例来验证算法的有效性。