Time-of-use (TOU) electricity pricing has been applied in many countries around the world
to encourage manufacturers to reduce their electricity consumption from peak periods to
off-peak periods. This paper investigates a new model of Optimizing Electricity costs during
Integrated Scheduling of Jobs and Stochastic Preventive Maintenance under time of-use
(TOU) electricity pricing scheme in unrelated parallel machine, in which the electricity price
varies throughout a day. The problem lies in assigning a group of jobs, the flexible intervals
of preventive maintenance to a set of unrelated parallel machines and then scheduling of jobs
and flexible preventive maintenance on each separate machine so as to minimize the total
electricity cost. We build an improved continuous-time mixed-integer linear programming
(MILP) model for the problem. To the best of our knowledge, no papers considering both
production scheduling and Stochastic Preventive Maintenance under time of-use (TOU) electricity
pricing scheme with minimization total Electricity costs in unrelated parallel machine.
To evaluate the performance of this model, computational experiments are presented, and
numerical results are given using the software CPLEX and MATLAB with then discussed.
Current fast development requires continuous improvement of employees’ skills and knowledge.
Therefore, companies are looking for the best way for improving the employees’ qualifications
and understanding of new concepts and tools which have to be implemented in
manufacturing areas. One method employs gamification for this purpose. The aim of this
paper is to present how gamification can increase the acquisition of knowledge concerning
lean manufacturing concept implementation. Gamification is an active learning approach for
people who will understand the subject easier by ‘feeling’ and ‘touching’ personally the analysed
problems. The research utilized a questionnaire which assessed the game participants’
engagement level. The assessment focused specifically on the participants’ motivation, cognitive
processing and social aspects. The participants were also examined before and after the
game in order to assess the increase of their understanding of different lean manufacturing
topics and tools. Five different games with different groups of participants were played. The
results confirmed the hypothesis that gamification has a positive impact on the knowledge
acquisition as well as on motivation, cognitive processing and social aspects. Finally, various
insights on how to better design, conduct and utilize gamification in the similar technical
context are presented.
Results of scientific researches show the trend of active using nitrides and borides of transition
metals and their combination in developing protective materials. While single elements
nitrides have been well studied, their multilayer modifications and combinations require
more detailed study. Physical-mechanical properties and structural-phase state of multilayer
coating according to the deposition conditions is an important task for the study.
It will be the analysis of physical-mechanical and electrical properties of coatings based on
refractory metals nitrides, their structure and phase composition and surface morphology
depending on the parameters of condensation. It was established the structure and behavior
of nano scale coatings based on refractory metals nitrides (Ti, Zr) depending on the size
of nano grains, texture, stress occurring in coatings.
In this article we present an industrial application of our mathematical model that integrates
planning and scheduling. Our main objective is to concretize our model and compare the
reel results with the theoretical ones. Our application is realized on a conditioning line of
pharmaceutical products at the ECAM EPMI production laboratory. For this reason and to
save time, we used Witness simulation tool. It gives an overall idea of how the line works,
the Makespan of each simulation and it highlights areas for improvement. We looked for
the best resulting sequence which corresponds to the minest Makespan and total production
cost. Then this sequence is applied on the conditioning line of pharmaceutical products for
simulation. On the other hand, we program our mathematical model with the parameters of
the conditioning line under python in version 3.6 and we adopt a simulation/optimization
coupling approach to verify our model.
Maintenance of process plants requires application of good maintenance practice due to
a great level of complexity. From a plant maintenance point of view, the most significant activity
is turnaround, an activity carried out through project task with long planning process
period and very short execution period, which makes it one of the most complex projects
of maintenance in general. It is exactly this kind of maintenance that is based on multidisciplinarity
which has to be implemented through the system of quality management on all
levels of maintenance management. This paper defines the most significant factors determining
the process of turnaround projects quality management and its efficiency. Such relation
is observed through moderating influence of complexity on process management efficiency
in the turnaround project. The empirical research was conducted based on the survey of
turnaround project participants in five refineries in Croatia, Italy, Slovakia and Hungary.
For exploring the influence of research variables testing of the target relation is carried out
by applying logistical regression. Research results confirm the significance of complexity as
variable that significantly contributes to the project performance through the moderating
influence on success of the project, as well as the influence of an efficient management on
a plant turnaround project key results. Beside theoretical indications, practical implications
that arise from this research study mainly refers to management process of the industrial
plant maintenance project.
Studies linking the use of lean practices to company performance have been increasing as
markets are becoming more competitive and companies are eager for reducing waste and
therefore implementing the Lean Management (LM) philosophy to improve performance.
However, results from these studies have found various and different impacts and some light
is needed. Extant literature was reviewed and, to achieve the research objective, a metaanalysis
of correlations was carried out. The obtained results suggest a positive relationship
between some lean practices and performance measures. Furthermore, the presence of moderators
influencing the relationship between lean practices and performance outcomes is
highlighted in our results. To our best knowledge, this is the first research that proposes
a comparison of results from primary studies on Lean implementation, by analysing the
linear relationship between lean practices and enterprise performance. It fills this gap and
therefore represents an important contribution.