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While steady-state analysis is useful, it does not consider the inherent transient characteristics of repairable systems' behavior, especially in systems that have relatively short life spans, or when their transient behavior is of special concern such as the motivating example used in this paper, military systems. Therefore, a maintenance policy that considers both transient and steady-state availability and aims to achieve the best trade-off between high steady-state availability and rapid stabilization is essential.

This paper studies the transient behavior of system availability under the Kijima Type II virtual age model. While such systems achieve steady-state availability, and it has been proved that deploying preventive maintenance (PM) can significantly improve its steady-state availability, this improvement often comes at the price of longer and increased fluctuating transient behavior, which affects overall system performance. The authors present a methodology that identifies the optimal PM policy that achieves the best trade-off between high steady-state availability and rapid stabilization based on cost-availability analysis.

When the proposed simulation-based optimization and cost analysis methodology is applied to the motivating example, it produces an optimal PM policy that achieves an availability–variability balance between transient and steady-state system behaviors. The optimal PM policy produces a notably lower availability coefficient of variation (by 11.5%), while at the same time suffering a negligible limiting availability loss of only 0.3%. The new optimal PM policy also provides cost savings of about 5% in total maintenance cost. The performed sensitivity analysis shows that the system's optimal maintenance cost is sensitive to the repair time, the shape parameter of the Weibull distribution and the downtime cost, but is robust with respect to changes in the remaining parameters.

Most of the current maintenance models emphasize the steady-state behavior of availability and neglect its transient behavior. For some systems, using steady-state availability as the sole metric for performance is not adequate, especially in systems that have relatively short life spans or when their transient behavior affects the overall performance. However, little work has been done on the transient analysis of such systems. In this paper, the authors aim to fill this gap by emphasizing such systems and applications where transient behavior is of critical importance to efficiently optimize system performance. The authors use military systems as a motivating example.

This study aims to provide control of liquids, especially against water-based ink on the paper and paperboard surface with natural substances, in also practical and greenway.

The paper surface was treated with natural rosin and its derivatives to obtain a hydrophobic effect and to improve printing properties. The oleoresin samples collected from Pinus nigra Arnold and Pinus pinaster Aiton trees in the controlled area and turpentine content removed was by hydrodistillation. The gum rosin (GR), fortified 10% with maleic anhydride (MGR) and esterified with 10% pentaerythritol (PMGR) samples solved in a simply alcohol and sprayed the base paper surface directly with a spray gun. Base paper samples were paperboard, bleached paper and test liner paper. Then, flexo printing was applied and printability properties were measured.

The treatment weights of these paper samples were 1.8 ± 0.5, 1.3 ± 0.5 and 0.7 ± 0.2 g/m², respectively, compared to the base paper. Greater Cobb60 results were obtained from modified rosin samples than unmodified gum rosin-sized paperboards and the PMGR surface treatment reduces Cobb60 values by 20% and MGR treatment reduces 15% comparing to the base sheet. Then, the printing procedure was applied to the surface of the treated materials using a flexo printing system. As a result of the treatment better print density, chroma and print lightness value consumed a less hydrophobic agent and controlling water-based flexo ink on the base paper surface.

The unique aspect of this work was improving the hydrophobicity of the paper surfaces was achieved by spraying with natural rosin and derivatives.

This study aims to evaluate the reuse of monumental structures through sustainability components, with the aim of emphasizing the sustainability of re-functional monumental structures.

In this study, which is based on situation analysis, urban inns in Samsun which is located in the Central Black Sea Region of Turkey, are discussed over the data obtained from archive and field studies in line with the environmental, social and economic sustainability criteria determined as a result of literature research.

The sustainability of the sample in the environmental, social and economic context has been revealed and what should be done for the sustainability of monumental structures over environmental, social and economic components has been discussed.

It has increased awareness of the environmental, social and economic dimensions of adaptive reuse as well as increasing the awareness of the buildings.

This study contributes to the literature in terms of evaluating monumental structures through the determined sustainability components. It is the first study on the sustainability of urban inns in the province of Samsun, the construction material of which is stone.

The main objective of this research is to unravel and analyze emergent technologies that are altering and improving the event industry. The study seeks to recognize the most vital technological advancement, uses and effects on event preparation, management and participant experience.

In this study, a narrative literature review method was used to examine emerging technologies in event management.

The research reveals that the emerging technologies examined in the articles affect and transform the event industry differently. Many of these technologies are currently being used in the event industry and are likely to be utilized in the coming years.

Numerous studies in the literature are related to the research field. However, as technology evolves rapidly, it is necessary to repeat studies at regular intervals. This article contributes to the literature by tracking new technological developments in the event industry.