Journal of Quality Engineering and Management

Abstract Today, degradation analysis is one of the most important approaches in evaluating the reliability of multi-component systems. As it is clear, improving the performance of real systems requires the use of efficient and predictable approaches to analyze degradation with considering the interaction of system degradation processes on each other. The literature review shows that degradation analysis of multi-component systems has been investigated in various researches, but the approach in which there is a profile relationship between the degradation processes of the system components has not been considered so far. When there is a functional relationship between the degradation processes of one or more components, it is called a profile in the statistical process control literature. The aim of this study is to provide an efficient approach to predict and evaluate the variability of degradation processes in the presence of multivariate profiles under the conditions of stochastic dependence. In fact, the proposed approach offers the possibility of predicting and evaluating the variability of degradation processes at the component and system level. In this paper, in order to evaluate the proposed approach, the data set of a multi-component system with a structure of 2 out of 3 has been used. The results show the effectiveness of the proposed approach.

Abstract application of Reliability can be seen in many industrial, communication, In the early stages of system design, many system features such as reliability, weight, cost, and etc are associated with uncertainty due to various reasons such as lifespan, operational conditions, etc. Since the use of the probabilistic approach in solving reliability problems has limitations and can only be used in quantitative analysis of information and in many cases does not produce useful and sufficient results for experts, therefore the use of the approach Fuzzy is much more efficient for solving reliability optimization problems. One of the ways to optimize the reliability is to allocate redundancy. When using redundant components in a subsystem, how the redundant components are used is particular importance. In reliability-redundancy allocation problems, the reliability of components is not known in advance and is considered as a decision variable. In the current research, the reliability-redundancy allocation problem has been investigated with two active and cold-standby redundancy strategies and the triangular fuzzy number approach has been used in using the parameters of probability functions and reliability calculation in two model problems and an industrial system. Genetic algorithm has been used to solve the problem. In the implementation of the genetic algorithm, the the random, tournament and roulette wheel methods has been used to select parents and different types of mutation and crossover operators have been used to produce children. The results are more efficient than the results obtained from solving the deterministic model.

Abstract The Permasin engine is a critical mission-oriented system, the failure of which will cause the failure of the main mission. Comprehensive studies on its reliability can be a step towards improving the performance of this system. The aim of the article is to analyze the reliability of the Permasin engine in the specified scenarios. In this article, first of all, the structure of Permasin engine as the studied system is described and the breakdown structure of the product is drawn for this system, and according to the mission-oriented nature of this system, there are 2 time scenarios, the basis of floating performance, definition and failure rate for sensitive parts from the standard. MilHDB-217 and NPRD-95 will be calculated in two optimistic and pessimistic modes. By using the breakdown structure, the connection of specific system components and the reliability block diagram are drawn in the Reliability Workbench software. Finally, the reliability of the subsystems and the studied system is calculated separately for both working scenarios. The results show that drive and motor subsystem has the lowest level of reliability compared to other subsystems in rated power.

Abstract Guiding the engineering process in systems has created an interdisciplinary approach called system engineering. The concept of guidance in the first step means choosing the best path among the existing paths and then guiding, directing and managing the process in the selected path. In this context, requirements management is one of the first stages of the product development process, which can engineer the requirements with a comprehensive and accurate view and produce a product that meets the needs of users.
The purpose of preparing this research, which was carried out in the period of 1402-1401, is to implement all requirements management activities in a marine system. For this purpose, at first, the basic requirements related to this product were extracted from different sources, categorized and then the metadata of the requirements was prepared, and one or more confirmation methods were provided for each of them. Finally, the relationship between the requirements has been determined and after resolving the conflicts between them, the metadata of the requirements has been updated. According to the results of this process, 106 requirements have been identified. These requirements will be considered as the basis for starting the product development and design process.

Abstract Cost, quality and design time of macro integrated products are important and necessary factors in design management. The aim of the current research is to provide an integration model for technological readiness, requirements statement document and also description of product features in the management of macro system design in domestic air base products. In particular, the research intends to reduce the time required for the final delivery of the product by identifying and prioritizing the real and prospective needs of customers/users, while applying gradual changes and evolutionary measures. The research method is survey-descriptive in terms of execution. In fact, the approach of data survey and analysis is carried out quantitatively using exploratory and confirmatory factor analysis. The results obtained from the significant factor loading coefficient and path coefficients as well as the test results of the research variables show the following. The significant coefficient of six paths - among the visible and hidden variables in addition to the components determined in the research conceptual model - is higher than 1.96 at the 95% reliability level. These numerical results confirm the research hypothesis and validity of the model fit.

Abstract Organizations have a unique role as drivers of the economic growth of countries. On the other hand, due to the rapid changes in technologies and business environment, the architecture of the organization based on the principles of the high reliability organization is very important. According to the mission of organizations, dynamic environmental conditions on one hand and the complexity of technologies that are constantly changing on the other hand, create the possibility of any kind of unexpected challenges in organizations. Therefore, organizations always need to use the principles of the organization with high reliability. The purpose of this research is to identify and quantify these principles. This research is applied and developmental in terms of purpose and its research method is combined (mixed method). In this research, qualitative data and then quantitative data have been collected. The statistical population of this research includes 50 experts and academics who are familiar with the issues of organization administration, management and reliability. The combination of qualitative and quantitative data is also exploratory, and the tool used is a questionnaire, so that the first stage uses qualitative approaches to achieve the principles of the organization with high reliability, and in the second stage, the discovered principles are completed and validated with a quantitative approach. The obtained results include six principles, resilience, acceptance of expertise, perceived risk, sensitivity of main executives, sensitivity to failures and mistakes, and organizational culture, which are the principles of the organization with high reliability