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The purpose of this paper is to explore the importance of physical proximity between schedulers and operators within manufacturing firms. In literature, a small distance between interdependent employees is assumed to be a prerequisite for a high level of coordination. This study investigates this assumption empirically for the relationship between scheduling and manufacturing and shows effects of proximity that are only partly in line with literature.

Consequences of relocating the scheduling department within a production firm are studied using a longitudinal case study approach. Data have been collected within three phases: before, three months after, and one year after the relocation.

Findings show that schedulers and operators communicate more face‐to‐face and less by phone after the relocation, especially during rescheduling. Furthermore, schedulers and operators perceived positive changes in ease of coordination and performance due to the relocation.

Scheduling and rescheduling are usually treated in literature as a mathematical puzzle to be solved. The authors do not contest this in itself, but the findings indicate that communication and collaboration are important aspects as well. In the case company, the possible negative aspects of close proximity, such as more interruptions, are offset by the advantages for rescheduling such as fast response and improved quality of communication. As the study was done in only one manufacturing firm, further research is needed to determine what firm characteristics specifically determine the appropriate location of the scheduling department.

The paper demonstrates the need to carefully design, manage, and facilitate the interface and critical task interdependencies between scheduling and manufacturing departments.

The paper contributes to operations management literature by providing a detailed empirical analysis concerning the effects of physical proximity between schedulers and manufacturing operators, including behavioural and organizational factors.

Successful implementations of scheduling techniques in practice are scarce. Not only do daily disturbances lead to a gap between theory and practice, but also the extent to which a scheduling technique can adequately model the processes on the shopfloor, and the extent to which the optimization goal of a technique matches the organizational goal are not great enough. Further, the schedulers’ actions may play an important role in the fulfilment of the generated schedules. The organizational structure with its different responsibilities and conflicting goals may also result in the poor performance of scheduling techniques. Besides these, there is the problem of measuring the quality of a schedule. Discusses the causes for these gaps and illustrates the solutions to improve scheduling by way of a case study.

Discusses the relationships between finite schedulers which operate on output from a higher level in a conventional MRPII system, and so‐called stand‐alone schedulers which essentially operate directly on orders. Presents two graphical models – a demand flow model and a flowpipe model – which help to explain the differences between such schedulers and are used to illustrate the key features of each. Coupled schedulers tend to work on demand which has already been smoothed or planned in some way and can be described as planning‐led, whereas stand‐alone schedulers work from unfiltered data, with the operator reacting to schedule quality (due‐date performance, resource activation levels, etc.) and thence adjusting resource and rerunning. Ascribes the growth of the stand‐alone scheduler, at least in part, to the greatly increased computing power available quite inexpensively on modern equipment.

The purpose of this paper is to make performance improvements and timely critical execution enhancements for operational flight program (OFP). The OFP is core software of autonomous control system of small unmanned helicopter.

In order to meet the time constraints and enhance control application performance, two major improvements were done at real‐time operating system (RTOS) kernel. They are thread scheduling algorithm and lock‐free thread message communication mechanism. Both of them have a direct relationship with system efficiency and indirect relationship with helicopter control application execution stability through improved deadline keeping characteristics.

In this paper, the suitability of earliest deadline first (EDF) scheduling algorithm and non‐blocking buffer (NBB) mechanism are illustrated with experimental and practical applications. Results of this work show that EDF contributes around 15 per cent finer‐timely execution and NBB enhances kernel's responsiveness around 35 per cent with respect to the number of thread context switch and CPU utilization. These apply for OFP implemented over embedded configurable operating system (eCos) RTOS on x86 architecture‐based board.

This paper illustrates an applicability of deadline‐based real‐time scheduling algorithm and lock‐free kernel communication mechanism for performance enhancement and timely critical execution of autonomous unmanned aerial vehicle control system.

This paper illustrates a novel approach to extend RTOS kernel modules based on unmanned aerial vehicle control application execution scenario. Lock‐free thread communication mechanism is implemented, and tested for applicability at RTOS. Relationship between UAV physical and computation modules are clearly illustrated via an appropriate unified modelling language (UML) collaboration and state diagrams. As experimental tests are conducted not only for a particular application, but also for various producer/consumer scenarios, these adequately demonstrate the applicability of extended kernel modules for general use.

As the real‐time applications used in today's wireless network grow, some schemes are required to provide better quality of services. From the evaluation of referenced scheduling scheme provided in IEEE 802.11e standard document, we know that it does not perform well on traffic which is not strictly constant‐bit‐rate (CBR). Therefore, it is necessary to design a more flexible scheme to dynamically adjust the estimation of transmission opportunity allocated to QoS‐enhanced stations with different characteristics of applications. This paper aims to present a data rate estimation algorithm for the scheduler of the IEEE 802.11e hybrid coordination function controlled channel access.

The performance of the algorithm is evaluated through Network Simulator ‐2.

With the proposed algorithm, the QoS access point can provide guaranteed parameters such as delay and throughput for both the real‐time variable‐bit‐rate and CBR traffics.

The paper presents a data rate estimation algorithm for IEEE 802‐11e HCCA scheduler.

Describes a production scheduler, which utilizes a hybrid push/pull approach to scheduling and exploits the expert system technology in order to obtain satisfactory solutions. The scheduler is applied to a multi‐stage production and inventory system, managed by make‐to‐order, with a large variety of incoming orders. The search for solution is made in respect of the due‐dates and under efficiency constraints (minimum lot, maximum storehouse levels, etc.). Considers order aggregation, both at portfolio and production level. Provides a dynamic rescheduling mechanism. Outlines theoretical arguments in favour of the scheduler and notes practical advantages as a consequence of the application of the scheduler in a firm which utilized a traditional despatching system.

Improvement of workflow scheduling in distributed engineering systems

The authors proposed a hybrid meta heuristic optimization algorithm.

The authors have made improvement in hybrid approach by exploiting of genetic algorithm and simulated annealing plus points.

To the best of the authors’ knowledge, this paper presents a novel theorem and novel hybrid approach.

The nano-router would be a mastery device for providing high-speed data delivery. Here nano-router with a space-efficient crossbar scheduler is used for making absolutely less consumption in power.

In the emerging modern technology, every one of us is expecting a delivery of data at a high speed. To achieve high-speed delivery the authors are using the router. The router used here is at nanoscale reading which provides a compact size.

This can be implemented using the modern tools called Quantum-dot Cellular Automata (QCA) which is operated without the use of a transistor. As conventional complementary metal oxide semiconductor (CMOS) designs have some limitations such as low density, high power consumption and requirement of a large area.

To overcome these limitations the QCA is used. It characterizes capability is used to substituting CMOS technology. The round-robin fashion is used in a high-speed space-efficient crossbar scheduler.

The simulation of the planned circuit with notional information established the practical identity of the scheme.

The proposed nano router can be stimulated in the QCA environment using the QCADesigner tool and the power of the router can be calculated with the QCADesigner–E tool.

The proposed nano router can be stimulated in the QCA environment using the QCADesigner tool and the power of the router can be calculated with the QCADesigner–E tool. In this work, the performance of the router can be done in both the QCA environment and CMOS technology.

The purpose of this paper is to present a study of the effect of different types of annealing schedules for a ribonucleic acid (RNA) secondary structure prediction algorithm based on simulated annealing (SA).

An RNA folding algorithm was implemented that assembles the final structure from potential substructures (helixes). Structures are encoded as a permutation of helixes. An SA searches this space of permutations. Parameters and annealing schedules were studied and fine-tuned to optimize algorithm performance.

In comparing with mfold, the SA algorithm shows comparable results (in terms of F-measure) even with a less sophisticated thermodynamic model. In terms of average specificity, the SA algorithm has provided surpassing results.

Most of the underlying thermodynamic models are too simplistic and incomplete to accurately model the free energy for larger structures. This is the largest limitation of free energy-based RNA folding algorithms in general.

The algorithm offers a different approach that can be used in practice to fold RNA sequences quickly.

The algorithm is one of only two SA-based RNA folding algorithms. The authors use a very different encoding, based on permutation of candidate helixes. The in depth study of annealing schedules and other parameters makes the algorithm a strong contender. Another benefit is that new thermodynamic models can be incorporated with relative ease (which is not the case for algorithms based on dynamic programming).

Three‐dimensional (3‐D) CAD and walk‐thru are promising technologies in design and construction. While gaining widespread acceptance in design, the use of 3‐D and walk‐thru during the construction phases of projects is evolving slowly. One significant barrier to acceptance includes lack of documented cost/benefit analysis. Experimental results reported herein provide quantitative evidence of the advantages of 3‐D CAD and walk‐thru for planning construction projects. The results provide strong evidence of the practical benefits and appropriate areas of application for 3‐D CAD and walk‐thru technology.