Railway track availability modelling with opportunistic maintenance practice

The geometry of railway track must be maintained within certain standards in order to provide a highly available network, as well as good ride comfort and safety for all rail users. Modelling is well utilised as part of asset management tools in exploring the effectiveness of different rail geometry maintenance strategies. By considering the rail route as an entire system – in contrast to a track section in isolation – a more effective maintenance strategy can be developed, including the deployment of opportunistic maintenance practice. This study presents a Coloured Petri Net model of railway track degradation, inspection, and maintenance planning and delivery, for an entire route of track sections. Opportunistic maintenance is introduced through a novel search transition function, which groups interventions based on local adjacency. Testing explores the availability and maintenance demands expected when following a series of different management strategies. This is extended to testing under heatwave conditions, a known disrupter to track geometry maintenance delivery. Simulation results show that in following an opportunistic strategy, greater availability can be achieved on the modelled rail line. Further, resilience to the heatwave disruptions can be achieved by selecting the correct maintenance strategy parameters. This asset management tool can provide guidance on management strategies for a full route of track sections as a combined system.

Software maintenance improvement in small software companies: Reflections on experiences

Software maintenance has been recognized as the most demanding and costly phase in the software life cycle. Software maintenance tasks, although require a more complex set of skills and knowledge, are far less interesting to software engineers than software development tasks. In addition, insight into the scholarly literature revealed that the knowledge basis on software maintenance is significantly less than the knowledge base on software development. Due to the obvious constraints of small software companies, they do not have time, people, and other resources for assessing and improving their software maintenance practice. This paper presents the author’s reflections on experience in assessing and improving software maintenance practice in an indigenous micro software company.

Non-Chemical Control of Annual Bluegrass (Poa annua) in Bermudagrass (Cynodon spp.) via Fraise Mowing: Efficacy and Barriers to Adoption

Fraise mowing is a maintenance practice that may serve as a non-chemical means of controlling the problematic weed annual bluegrass (Poa annua L.) in bermudagrass (Cynodon spp.) given reports of efficacy on other turfgrass species. However, an understanding of practitioner decision-making in implementing fraise mowing as a weed-control measure remains unknown. A field study was conducted in Knoxville, TN and repeated in space in Jay, FL during summer 2019 to assess bermudagrass regrowth and subsequent annual bluegrass control, following fraise mowing at depths of 1.5 and 3.0 cm compared to a non-treated check (0 cm). Bermudagrass recovered more quickly at the 1.5 cm depth than the 3.0 cm depth and was the swiftest in Florida. Fraise mowing at either depth resulted in a 41–97% reduction in annual bluegrass populations. A qualitative study was conducted in spring 2021, which engaged eight turfgrass managers from Tennessee and Florida via individual interviews in order to understand barriers and challenges to fraise mowing application. Turfgrass managers had positive views of fraise mowing but described challenges in implementation for weed control including cost, labor, area closure, and debris removal.

Cremated animal remains and shattered pottery. Rare ritual deposits from the Middle to Late Bronze Age at Aalst – Siesegemkouter (Belgium)

Archaeological research at Aalst – Siesegemkouter revealed several pits within a Middle to Late Bronze Age settlement. Most of them hardly contained any artefacts, but one exception showed a structured stratigraphy with an abundance of finds, including a large amount of shattered pottery, charcoal and calcined animal bone. The study of this assemblage, and comparison with two other pits showing similarities, provides strong indications of a closing deposit or another type of ‘site maintenance practice’. In the Low Countries, comparable contexts generally date from the Iron Age, suggesting that the finds from Aalst – Siesegemkouter represent early forerunners of this ritual practice. On top of this early date, the large volume of cremated animal bone represents an almost unique characteristic for which, until now, parallels from the Metal Ages have hardly been found, even on a Northwestern European scale. In general, the role played by organic remains in ritual contexts from these periods and regions is poorly understood, often due to bad preservation conditions or the lack of a multidisciplinary approach.

MAINTENANCE MANAGEMENT DETERMINANTS APPRAISAL OF HOSPITAL BUILDINGS

This research examines the maintenance practice of hospital buildings in Malaysia. Recently, the increment of hospital buildings’ accidents has affected its performances as a result of determinants. However, the maintenance practice employed in the hospitals has a direct impact on the performance of hospital buildings. The fast-growing population of Malaysia necessitates proactiveness on the part of the government regarding the provision of efficient healthcare and ensuring the wellbeing of the citizenry. In this regard, the state of hospital buildings is inextricably linked to quality healthcare. This study evaluates the determinants that impair the quality of hospital buildings in Malaysia in order to improve their efficiency and preempt the avoidable building pitfalls through effective maintenance management. The survey questionnaire was used in order to achieve the objective of this study to users of hospital buildings, the outcomes sought after concerned building component issues such as finishes, cleanliness, aesthetics, ventilation and other determinants that affected the performance of the hospital buildings. The results showed that specific determinants including lighting, ventilation, fire alarms, fire extinguisher signage, floor conditions, lifts and quality of air depreciate the performance of hospital buildings. In addition, the procurement methods of maintenance work are completely outsourcing in hospitals and combinations of outsourcing and in-source methods in a private hospital. Moreover, the study found that the current methods of maintenance management adopted for hospital buildings remain typically corrective. This has always resulted in deprived user satisfaction, unproductive service delivery, and the prolongation of diverse maintenance problems.

OBSTACLES OF IMPLEMENTING GREEN MAINTENANCE MANAGEMENT IN HOSPITAL BUILDINGS

Demand for green hospital buildings is increasing. While some hospital buildings were designed and constructed as green buildings, many hospital buildings have been upgraded to comply with the green requirements. Green hospital buildings require green maintenance practice. In comparison, procuring green buildings is easy as compared to green maintenance. Through unstructured interviews involving 3 hospitals, this research investigated the complications in the implementation of green maintenance in hospital buildings. The research found that lack of awareness, financial constraints/government support, new technologies, and top management support were the major obstacles toward the implementation of green maintenance. The results also confirmed that the maintenance of hospital buildings is corrective, reactive, and cost-driven. The salient finding from this research is that the maintenance organizations have a poor understanding of the concept of green maintenance practices. Saving energy costs are the main purpose of implementing green maintenance in hospitals. From an ontological point of view, the main findings of this research on the constraints of the implementation of green maintenance are generalizable to other types of buildings in and outside of Malaysia.

Tribology and Maintenance of Machinery – A Review

The present paper considers the tribological principles on the maintenance of machinery whose three important areas are – Preventive, Condition Based and Proactive. Although breakdown is kept out of view, the morphology and analysis of failure provide important inputs for maintenance strategies. Condition based maintenance depends on three D’s – Detection, Diagnosis and Decision. In many machinery systems, the problem of predicting the remaining useful life – the Proactive part of the program, and evaluating the cost benefits are of enormous importance. Here the authors endeavor to highlight how the tribologist can significantly improve the maintenance practice.

Tribology and Maintenance of Machinery - A Review

The present paper considers the tribological principles on the maintenance of machinery whose three important areas are – Preventive, Condition Based and Proactive. Although breakdown is kept out of view, the morphology and analysis of failure provide important inputs for maintenance strategies. Condition based maintenance depends on three D’s – Detection, Diagnosis and Decision. In many machinery systems, the problem of predicting the remaining useful life – the Proactive part of the program, and evaluating the cost benefits are of enormous importance. Here the authors endeavor to highlight how the tribologist can significantly improve the maintenance practice