The Swedish Transport Administration is introducing a new regime, called maintenance windows, for allocating train free slots reserved for maintenance tasks on the railway infrastructure. In this paper, a model for the assessment and the dimensioning of such maintenance windows is presented, which considers marginal effects on both the maintenance cost and the expected train traffic demand. The...

There is mounting evidence that prefrontal cortex (PFC) is activated during mnemonic operations such as working memory maintenance and also during response-related operations. In the current study, we examine the neural organization of mnemonic and response operations with respect to each other within PFC. Stimulus-evoked and sustained functional MRI activity was recorded during performance of ...

Abstract: Equipment maintenance is one of the core tasks in power system operations. The premise and foundation for maintenance is to establish a power equipment maintenance model, which should reflect all equipment states accurately including operation, inspection and maintenance. On the basis of the analysis of the traditional state diagram probability model, an improvement is put forward to ...

PROSUR and SIAT Programs It is important that document and procedure configuration controls be managed closely to adequately promote reactor safety. The PROSUR and SIAT Programs provide important elements of this control. PROSUR The Prosur program is a single reference program that encompasses all plant system activities, for example: maintenance, operations, chemistry, surveillance tests. The ...

With large expansion plans for the offshore wind turbine industry there has never been a greater need for effective operations and maintenance. The two main problems with the current operations and maintenance of an offshore wind turbine are the cost and availability. In this work a simulation model has been produced of the maintenance process for a wind turbine with the aim of developing a pro...

This paper identifies requirements and proposes a surface collision detection algorithm for assisting in assembly/disassembly and maintenance verification operations in virtual prototype environments. Virtual prototype models are defined as a collection of surfaces. Available collision detection toolkits for virtual environments are based on polygons. The integration of surface knowledge into t...

Maintaining accurate neighbor information in wireless networks is an important operation upon which many higher layer protocols rely. However, this operation is not supported in the IEEE 802.11 MAC layer, forcing applications that need it to each include their own neighborhood mechanism, creating redundancies and inefficiencies and failing to capitalize on potential synergies with other MAC lay...

It is widely recognized that production rules in database systems can be used to automatically maintain derived data such as views. However, writing a correct set of rules for e ciently maintaining a given view can be a di cult and ad-hoc process. We provide a facility whereby a user de nes a view as an SQL select expression, from which the system automatically derives set-oriented production r...

In this paper, we consider joint scheduling of jobs and preventive maintenance operations on a single machine with an objective to minimize the total earliness and tardiness of jobs about a common due date. The properties of an optimal schedule are identified and utilized to develop a constructive heuristic and a lower bound estimate. The properties are also utilized to hybridize Tabu search a...

Industrial maintenanceoperations involve various occupational risks. Despite the accidents that have occurred, there has not been any task-based risk assessment tool for companies. A study was carried out with the aim of defining the requirements for a task-based risk assessment tool for industrial maintenance. The study charted risks on sites, the occurrence and type of severe and fatal accide...