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Studies the concept of subsystems and introduces two important classes of systems. One class contains systems with the property of complete subsystems and the other contains systems with the property of completely trivial subsystems. Discusses the following questions in great detail and uses the results in the research of linearly ordered sets, partially ordered sets, ordered groups and ordered algebras: existence, heredity, infinity, cardinality, proper classes, proper subclasses, categories, isomorphic categories, etc.

In systems theory, authors such as Klir, Miller, Yang, Lin and Ma, Backlund, etc. have developed different definitions of the system concept in function of both the type of variables used and the type of connection between variables. The concept of the subsystem, however, tends not to vary substantially from author to author, and this leads to a new system definition based on the subsystem concept, analysing the possible cases of interaction between subsystems and obtaining results for the overall system from an analysis of its subsystems.

The purpose of this article is to determine if there is a linkage between the army material systems analysis activity (AMSAA) reliability growth models at the system and subsystem levels and at the subsystem and functional levels of indenture. If such a linkage exists, how this information can be used when tracking reliability of fielded systems to provide early warning signals to detect unwanted reliability problems at lower levels, where improvements are typically made.

Actual performance data from large equipments were analyzed for several groupings of such equipment, where equipment age and generation of design determined the groupings. For each dataset, the system‐level trend was measured using the AMSAA model for three different cases. For each of the three cases, all subsystem trends were measured, in addition to the system‐level trend. This was done to see if any relationship exists, as hypothesized, between system and subsystem trends. Data were analyzed using three different combinations of time periods to facilitate a later investigation of the predictive capabilities of the AMSAA model.

Results indicate that, for large complex systems or equipment, there appears to be a linkage at the subsystem and functional levels. However, no such hazard rate trending relationship exists between the system and subsystem levels. Based on these results, it can be cautiously concluded that, in terms of reliability, in subsystems that exhibit an increasing trend in unwanted issues, there is a higher likelihood of a function that is driving such a trend.

A useful approach in reliability studies to see if the hazard rate trending relationships between levels of hardware indenture exists as one progresses toward the system‐level. For large complex systems or equipments, such as the one represented here, the initial results indicate that the answer is no, at least between the system and subsystem levels of indenture. However, there is strong evidence that such relationships are valid between subsystems and their functions.

This paper advances existing knowledge in the area of reliability analysis by exploring the use of army material systems analysis activity (AMSAA) reliability growth models to determine linkages between the system and subsystem levels and at the subsystem and functional levels of indenture. If such a linkage exists, it is possible to determine how this information can be used to provide early warning signals when tracking reliability of fielded systems.

The purpose of this paper is to expound the concept of the coordinated development of the transport system, and provide a quantitative method to support decision making in urban transportation development planning.

To analyze the organic composition of urban transport system, research the meaning and mechanism of coordinated development of transport system. On the basis of researching relations of transport and external systems and its subsystems, to research quantitative theoretical model of the coordinated development and assessment of the transport system.

Establishing models needs to analyze the coordination among the various indices of subsystem, calculate the overall coordination between indices of the subsystem and all the indices of other subsystems, then inspect the coordinated development among subsystems.

How to design the indexes of the subsystem of urban transport system is the main limitation.

Offering theoretical foundation for coordinated development of urban transport system.

Putting forward quantitative theoretical model on coordinated development of urban transport system, which lays a foundation for further study.

This study proposes targeted modernization of the Department of Defense (DoD's) Joint Forces Ammunition Logistics information system by implementing the optimized innovative information technology open architecture design and integrating Radio Frequency Identification Device data technologies and real-time optimization and control mechanisms as the critical technology components of the solution. The innovative information technology, which pursues the focused logistics, will be deployed in 36 months at the estimated cost of $568 million in constant dollars. We estimate that the Systems, Applications, Products (SAP)-based enterprise integration solution that the Army currently pursues will cost another $1.5 billion through the year 2014; however, it is unlikely to deliver the intended technical capabilities.

The purpose of this paper is to propose a method to compute RAMD indices to measure and improve the performance of skim milk powder production system of a dairy plant under real working conditions.

The present work is carried out by developing performance model based on Markov birth-death process. The skim milk powder production system consists of six units. The first order governing differential equations are derived using the mnemonic rule and further solved to calculate RAMD indices i.e. reliability, availability, maintainability, dependability, MTBF, MTTR and dependability ratio for each subsystem of the system.

The subsystem SS1 comprising of chiller and cream separator is the most critical from maintenance point of view, as the reliability, availability, maintainability, dependability, MTBF and dependability ratio indices are low as compared to those of other subsystems of skim milk powder production system of the dairy plant.

The RAMD indices of the present work is very useful for finding the critical subsystem and its effect on the performance of the system working under real working conditions. Further, based on findings the maintenance priorities for various subsystems can be decided.

The purpose of this paper is to study the impact of restructuring in the manufacturing system at the conceptual stage using graph theoretic model.

Some restructuring decisions are conceptualized which reflect the aim of the organization to gradually evolve the manufacturing system towards a leaner structure. This is achieved by way of defining simplified procedures so that lesser hindrance in terms of cycles of interactions is encountered. The restructuring decisions are represented by five restructured configurations of the manufacturing system, through gradual removal of appropriate interaction links. The graph theoretic models are developed for original configuration and each of the new restructured configurations and the resulting structural characterization information is used to compare the structure of restructured configurations with the original configuration. The value of the coefficient of dissimilarity of each of the new configurations with respect to the original configuration is obtained to have a quantitative estimate of the simplification that may be achieved by different contemplated restructuring decisions.

The present work shows that the restructuring decisions can be represented by different configurations in the form of schematic diagrams involving minor changes in the interaction structure among subsystems of the manufacturing system. The quantitative analysis using coefficient of dissimilarity for restructuring decisions indicated that there are varying levels of impact created by five comparable restructuring decisions considered in the study. The findings have a potential to guide the restructuring efforts by identifying a focus area that can produce greater impact of restructuring.

The findings are valid for a particular case manufacturing organization which does not involve itself in extensive design activity. The study is based on the assumption that the schematic diagram and graph theoretic model captured all the relevant influencing factors of the manufacturing system.

The study provides an easy to use methodology for the practical decision makers in manufacturing industry striving to improve the performance of their organization. It can provide the analysis of restructuring decisions at the conceptual stage itself without the necessity of disturbing the normal functioning of the organization. There is a scope for identifying focus areas where the restructuring may yield comparatively greater dividends.

The study of restructuring by representing it in the form of changes in interactions among subsystems of a manufacturing system and investigation of the impact of such restructuring efforts at the conceptual stage using graph theoretic model has been carried out for the first time.

The focus of this paper is on reliability and availability design goals. It aims to provide top‐level estimates of the safety and maintainability of future spacecraft systems.

The developed design tool uses basic reliability principles to estimate the probability of a safe mission and the need for repairs/replacement during ground processing, before launch and start of mission, based on the characteristics of the vehicle's main systems: the number of subsystems, the mean time to repair, and the per subsystem average reliability.

A simple reliability, maintainability and safety model is developed to support the top‐level design process of future space transportation vehicles. It also describes how the developed design tool uses various sensitivity analysis functions to improve design decisions.

The goal of the developed tool is to provide engineers/vehicle developers during the early stages of design with a tool that demonstrates the effect on maintainability of improving component reliability and reducing the number of components.

The purpose of this paper is to develop further understanding of the interdependence between product and organization subsystems in the context of major projects by empirically elaborating the volume-variety matrix.

Projects are perceived as systems that include a product subsystem (the project outcome) and an organization subsystem (the temporary multi-firm organizational network that produces the project outcome). This study addresses product-organization interdependence by analyzing product and organization subsystem components in terms of their uniqueness and reuse across multiple projects. The empirical analysis focuses on four global renewable fuels refinery projects implemented by Neste from 2003 to 2011. The refineries are based on the same proprietary technology but are unique at the project level.

The findings indicate interesting interdependencies between product and organization subsystems when analyzed at the component level: the findings suggest both diagonal and off-diagonal positions in the volume-variety matrix. An example of an off-diagonal position is a reused organization subsystem component associated with a unique product subsystem component, meaning that choosing the same organization in a future project can be used for acquiring an improved and, thereby, unique product subsystem component.

The study elaborates upon the volume-variety matrix in the context of major projects. The findings related to off-diagonal positions in the matrix provide new knowledge on combinations at the component level where a reused organization can be associated with a unique product, and vice versa. This has direct implications for management of projects.