Manufacturers have to look constantly for new strategies and tools to improve processes, decrease cost and increase productivity and efficiency. Production scheduling is one of the crucial elements in manufacturing and has an impact on delivery deadlines and also on the production process in terms of its utilization. On the other hand, the value stream optimization is very important for lean manufacturing efforts. This paper is aimed to research the impact of job shop scheduling on value stream optimization and decreasing of cost-time investment. Value stream mapping represents a very efficient tool for visualization of activities within production flow focused on activity duration with the purpose to eliminate non-value added activities. Value stream costing is based on value stream and eliminates the need for overhead allocation and calculation. Cost-time profile is a powerful tool for visualization and calculation of cost accumulation during the time across the entire manufacturing flow. Software tools used in this paper are: Lekin scheduling system for constructing the schedules based on four different dispatching rules and Cost-Time Profiler software for simulating the impact of different schedules on total production cost and cost-time investment (representing the time value of money), which is proposed as a new scheduling objective function.

In the process of hydraulics systems design various software simulation systems are used. However, the increase of efficiency of the designed hydraulic systems can be achieved in two ways: by making design modifications based on reliability theory, on one hane, or based on monitoring of system operating parameters, on the other. In this paper, a case study of the improvement of a designed and implemented hydraulic system is reviewed, using those two approaches. Based on the data collected by monitoring the system operating parameters, and the system reliability analysis, it was possible to increase the efficiency of the hydraulic system either it the initial design stage, or during system realization. The result of such an approach is the hydraulic system which successfully operates 24 hours a day, without failure, which indicates that the proposed method of system analysis and improvement allows significant enhancement of hydraulic system efficiency.

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The implementation of management systems in organizations is often based on a "blind" meeting of requirements set by the selected standard, while these requirements are not in direct relation to the risks of the organizations. Therefore, it often happens that the established management system is not operational or is not aligned with the context and real needs of the organization. This paper presents general model for the design of an integrated management system based on risk assessment of organization's processes. The model was based on the primary hypothesis that a process that has a higher risk should be described in more detail in order to be adequately realized. The presented Model was tested on three diverse companies which had already implemented management systems according to international standards. Comparing the existing with the projected documentation in three companies, it was concluded that the number, scope and structure of documented information were optimized for successful risk management, which lowers the overall costs and enables efficient management of the company. The paper provides scientific approach and methodology for designing the integrated management system in any organization, using existing risks as universal integrating factor.

For this research, an ad hoc questionnaire was sent to a representative sample of quality ma na gers in Serbian certified organisations to determine their estimate of the quality management principles ap plication (QMPA) as an overall estimate of management commitment to quality management practice. In a stable business environment, high impact of TQM elements application to the QMPA is likely to be ex pected. Objective parameters (number of employees, form of ownership of organisation, etc.) are not likely to form significant variations in managers' perceptions of TQM elements. It is determined that only a few of the selected TQM elements are predictors of a subjective estimate of the QMPA (estimates of QMS, changes after certification, human resource management and process management). Observed objective parameters (number of employees and whether an organisation is employing a network administrator or not) showed statistically significant variations in estimates of TQM elements. Research results point to the conclusion that Serbia is yet to take the long journey towards raising awareness about the management commitment to QM and TQM practice. It is possible that other economies in transition also have similar problems in this area.