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The purpose of this paper is to develop a computer simulation model to evaluate the bowl phenomenon and the allocation at the end of the line of stations with either greater mean operation times or higher variability of operation times.

The model was developed on the basis of a realistic case problem and applied to a six‐station assembly line. The evaluation criteria were the: minimization of the total elapsed time; maximization of the average percentage of working time; and minimization of the average time in the system.

The performance of an assembly line with independently normally distributed operation times could be improved by applying the bowl phenomenon. The allocation of large operation mean times to stations located near the end of the line did not produce improved results. Instead a more balanced allocation proved to be more significantly effective. On the other hand, the assignment of larger variability of operation times to the stations near the end of the line improved the performance of the assembly line.

The investigation contributed to the computer simulation approach to solving assembly line problems that dealt with the impact of normally distributed operation times on the bowl phenomenon and assembly lines with increasing mean operation times and higher variability of operation times at the end of the line of stations.

This paper is aimed at comparing cellular manufacturing with focused cellular manufacturing. We define focused cellular manufacturing as a layout scheme that groups components by end‐items and forms cells of machines to fabricate and assemble end‐items. It is not classified as a cellular manufacturing layout since it does not attempt to take advantage of process similarities. It also is not classified as a flow shop since there are no machines dedicated to individual operations and the machines are not arranged in a series. In addition, this research includes batching and assemble times in its criteria which few researchers in this area have done. The results indicate that the focused cellular manufacturing scheme has a batching advantage. This advantage out‐weighed the set‐up time reduction advantage of the cellular manufacturing scheme for average end‐item completion times and average work‐in‐process inventory levels. The cellular manufacturing scheme overcame the batching advantage only when there were small batch sizes or large set‐up time magnitudes.

To achieve a full understanding of the role of marketing from plan to profit requires a knowledge of the basic building blocks. This textbook introduces the key concepts in the art or science of marketing to practising managers. Understanding your customers and consumers, the 4 Ps (Product, Place, Price and Promotion) provides the basic tools for effective marketing. Deploying your resources and informing your managerial decision making is dealt with in Unit VII introducing marketing intelligence, competition, budgeting and organisational issues. The logical conclusion of this effort is achieving sales and the particular techniques involved are explored in the final section.

This study aims to improve the passenger accessibility of passenger demands in the end-of-operation period.

A mixed integer nonlinear programming model for last train timetable optimization of the metro was proposed considering the constraints such as the maximum headway, the minimum headway and the latest end-of-operation time. The objective of the model is to maximize the number of reachable passengers in the end-of-operation period. A solution method based on a preset train service is proposed, which significantly reduces the variables of deciding train services in the original model and reformulates it into a mixed integer linear programming model.

The results of the case study of Wuhan Metro show that the solution method can obtain high-quality solutions in a shorter time; and the shorter the time interval of passenger flow data, the more obvious the advantage of solution speed; after optimization, the number of passengers reaching the destination among the passengers who need to take the last train during the end-of-operation period can be increased by 10%.

Existing research results only consider the passengers who take the last train. Compared with previous research, considering the overall passenger demand during the end-of-operation period can make more passengers arrive at their destination. Appropriately delaying the end-of-operation time can increase the proportion of passengers who can reach the destination in the metro network, but due to the decrease in passenger demand, postponing the end-of-operation time has a bottleneck in increasing the proportion of passengers who can reach the destination.

This paper proposes introducing how to consider the break which cyclically happens and has nothing to do with resource availabilities in modeling of a construction process through an activity‐based simulation.

In consideration of the variable break‐frequency and break‐duration for different activities, concepts of time‐cycle and time‐window are discussed. Then an algorithm to determine the execution of the activities facing the cyclical break is proposed, in which pre‐emption or non‐pre‐emption cases and overtime are taken into account together. This algorithm is incorporated into an activity‐based simulation so that the improved construction simulation is able to consider the cyclical break and model the construction process more reasonably. Computational analyses are presented to address the effectiveness of the improved activity‐based simulation.

The computational analyses demonstrate that the improved activity‐based simulation can consider the cyclical break in modeling a construction process, which cannot be achieved by the traditional simulation tools, especially when non‐pre‐emptive activities are concerned. It is also shown that the overtime use for the non‐pre‐emptive activities can lead to reduction of the project duration when the cyclical break is considered.

The proposed simulation‐based methodology is an alternative means to deal with the cyclical break that is destined for some activities and irrelevant to resource availabilities in modeling of a construction process.

The purpose of this paper is to propose a four‐level hierarchy model for multimedia documents representation to be used during the dynamic scheduling and altering of multimedia contents.

The four‐level hierarchy model (object, operation, timing, and precedence), offers a fine‐grain representation of multimedia contents and is embedded within a research tool, which is called WEBCAP. WEBCAP utilizes the four‐level hierarchy to synchronize the retrieval of objects in the multimedia document employing Allen's temporal relations, and then applies the Bellman‐Ford's algorithm on the precedence graph to schedule all operations (fetch, transmit, process, and render), while satisfying the in‐time updating and all web workload's resources constraints.

The experimental results demonstrate the effectiveness of the model in scheduling the periodical updating multimedia documents while considering a variety of workloads on web/TCP.

WEBCAP should be enhanced to automatically measure and/or approximate the available bandwidth of the system using sophisticated measurement of end‐to‐end connectivity. In addition, WEBCAP should be expanded and enhanced to examine system infrastructure for more real‐time applications, such as tele‐medicine and e‐learning.

WEBCAP can be used as an XML markup language for describing multimedia presentations. It can be used to create online presentations similar to PowerPoint on desktop environment, or used as an interactive e‐learning tool. An HTML browser may use a WEBCAP plug‐in to display a WEBCAP document embedded in an HTML/XML page.

This paper proposed a dynamic scheduling of multimedia documents with frequent updates taking into consideration the network's workload to reduce the packet lost ratio in the TCP flow, especially in the early stages. WEBCAP can be used to guide distributed systems designers/managers to schedule or tune their resources for optimal or near optimal performance, subject to minimizing the cost of document retrieval while satisfying the in time constraints.

Construction‐oriented discrete‐event simulation often faces the problem of defining uncertain information input, such as subjectivity in selecting probability distributions that result from insufficient or lack of site productivity data. This paper proposes incorporation of fuzzy set theory with discrete‐event simulation to handle the vagueness, imprecision and subjectivity in the estimation of activity duration, especially when insufficient or no sample data are available. Based upon an improved activity scanning simulation algorithm, a fuzzy distance ranking measure is adopted in fuzzy simulation time advancement and event selection for simulation experimentation. The uses of the fuzzy activity duration and the probability distribution‐modeled duration are compared through a series of simulation experiments. It is observed that the fuzzy simulation outputs are arrived at through only one cycle of fuzzy discrete‐event simulation, still they contain all the statistical information that are produced through multiple cycles of simulation experiments when the probability distribution approach is adopted.

The purpose of this paper is to investigate the scheduling problem of real-time jobs executing on a DVS processor. The jobs must complete their executions by their deadlines and the energy consumption also must be minimized.

The two-phase energy-efficient scheduling algorithm is proposed to solve the scheduling problem for real-time jobs. In the off-line phase, the maximum instantaneous total density and instantaneous total density (ITD) are proposed to derive the speed of the processor for each time instance. The derived speeds are saved for run time. In the on-line phase, the authors set the processor speed according to the derived speeds and set a timer to expire at the corresponding end time instance of the used speed.

When the DVS processor executes a job at a proper speed, the energy consumption of the system can be minimized.

This paper does not consider jobs with precedence constraints. It can be explored in the further work.

The experimental results of the proposed schemes are presented to show the effectiveness.

The experimental results show that the proposed scheduling algorithm, ITD, can achieve energy saving and make the processor fully utilized.

Previous studies approach surgery scheduling mainly from the mathematical modeling perspective which is often hard to apply in a practical environment. The aim of this study is to develop a practical scheduling system that considers the advantages of both surgery categorization and newsvendor model to surgery scheduling.

The research was carried out in a Finnish orthopaedic specialist centre that performs only joint replacement surgery. Four surgery categorization scenarios were defined and their productivity analyzed by simulation and newsvendor model.

Detailed analyses of surgery durations and the use of more accurate case categories and their combinations in scheduling improved OR productivity 11.3 percent when compared to the base case. Planning to have one OR team to work longer led to remarkable decrease in scheduling inefficiency.

In surgical services, productivity and cost‐efficiency can be improved by utilizing historical data in case scheduling and by increasing flexibility in personnel management.

The study increases the understanding of practical scheduling methods used to improve efficiency in surgical services.