• TECHNOLOGICAL BASIS OF “INDUSTRY 4.0”

    A COMPARISON OF SEQUENTIAL QUALITY CONTROL METHODS

    Industry 4.0, Vol. 3 (2018), Issue 2, pg(s) 62-65

    This research considers the problem of sequential quality control and presents different methods for the quick detection, with low false alarm rate, of a change in a stochastic system. The paper focuses on recently proposed control schemes called Nested Plans. These schemes include two unknown parameters that essentially impact their efficiency. The research presents a way to find the optimal values of the parameters, and shows that Nested Plans with the correct choice of the parameters are very efficient, robust and simple for practical applications.

  • BUSINESS

    THE PROBLEM OF OVERLAPPING PROJECT ACTIVITIES WITH INTERDEPENDENCY

    Science. Business. Society., Vol. 1 (2016), Issue 6, pg(s) 19-22

    This paper analyzes a simple project with two activities. The activities can be executed in a serial mode (separately), in a parallel mode (overlapping), or in a mixed mode (partly in a serial mode and partly in a parallel mode). There is interdependence between the activities and the duration-budget tradeoffs functions of the activities are defined differently for each execution strategy. The paper presents a deterministic duration-budget tradeoff model that takes into account the interdependence between the activities in order to determine the optimal execution-mode and the budget distributions among the project activities. A stochastic extension of the proposed model is also considered. The presented analysis can help project managers and practitioners in choosing the optimal overlapping strategy for different objective functions and constraints.

  • A MULTINOMIAL APPROACH TO THE MACHINE INTERFERENCE PROBLEM

    Machines. Technologies. Materials., Vol. 10 (2016), Issue 1, pg(s) 3-6

    This paper presents a multinomial model for a special case of the machine interference problem (MIP), where each of N identical machines randomly requests several different service types. The model allows the calculation of the expected interference time in the queue for each service type. The extended version of the model allows calculation of the exact distribution function of the steady state waiting time and total service time for each type of requested service. In addition, the model can be adjusted for the case where the service is provided by a group of K identical operators, each operator is capable to handle all types of service, but each service type has a different priority.