A study of the selection of microcomputer architectures to automate planetary spacecraft power systems

Performance and reliability models of alternate microcomputer architectures as a methodology for optimizing system design were examined. A methodology for selecting an optimum microcomputer architecture for autonomous operation of planetary spacecraft power systems was developed. Various microcomputer system architectures are analyzed to determine their application to spacecraft power systems. It is suggested that no standardization formula or common set of guidelines exists which provides an optimum configuration for a given set of specifications

A general graphical user interface for automatic reliability modeling

Reported here is a general Graphical User Interface (GUI) for automatic reliability modeling of Processor Memory Switch (PMS) structures using a Markov model. This GUI is based on a hierarchy of windows. One window has graphical editing capabilities for specifying the system's communication structure, hierarchy, reconfiguration capabilities, and requirements. Other windows have field texts, popup menus, and buttons for specifying parameters and selecting actions. An example application of the GUI is given

Profitability, reliability and condition based monitoring of LNG floating platforms: a review

The efficiency and profitability of Floating, Production, Storage and Offloading platform (FPSO) terminals depends on various factors such as LNG liquefaction process type, system reliability and maintenance approach. This review is organized along the following research questions: (i) what are the economic benefit of FPSO and how does the liquefaction process type affect its profitability profile?, (ii) how to improve the reliability of the liquefaction system as key section? and finally (iii) what are the major CBM techniques applied on FPSO. The paper concluded the literature and identified the research shortcomings in order to improve profitability, efficiency and availability of FPSOs

PERFORMANCE EVALUATION MODELING OF PRE-TREATMENT UNIT IN GAS PROCESSING PLANT

This paper presents a report for Final Year Project (FYP). The title of the research project is Performance Evaluation Modeling of Pre-Treatment Unit (PTU) in Gas Processing Plant which under manufacturing from mechanical field. The project is conducted at one of Gas Processing Plant which is Pre-treatment Unit (PTU). The project started with identification of critical component for PTU, construction of reliability block diagram (RBD) and reliability analysis based on RBD model. During the completion of the project, the researcher has been assisted by reliability engineer from PETRONAS Gas Berhad in verifying the RBD model. The outcome of this project is a model of reliability that could be used by plant management to evaluate the current reliability of the PTU. Besides, this research can analyze whether that equipment has achieved target plant reliability and identify the sub-component that reduces the overall reliability of the system. This paper includes introduction, literature review, methodology, result and discussion and conclusion. The report will include introduction, literature review and theory, methodology, result and discussion, conclusion and recommendation and reference

Redundant VoD Streaming Service in a Private Cloud: Availability Modeling and Sensitivity Analysis

For several years cloud computing has been generating considerable debate and interest within IT corporations. Since cloud computing environments provide storage and processing systems that are adaptable, efficient, and straightforward, thereby enabling rapid infrastructure modifications to be made according to constantly varying workloads, organizations of every size and type are migrating to web-based cloud supported solutions. Due to the advantages of the pay-per-use model and scalability factors, current video on demand (VoD) streaming services rely heavily on cloud infrastructures to offer a large variety of multimedia content. Recent well documented failure events in commercial VoD services have demonstrated the fundamental importance of maintaining high availability in cloud computing infrastructures, and hierarchical modeling has proved to be a useful tool for evaluating the availability of complex systems and services. This paper presents an availability model for a video streaming service deployed in a private cloud environment which includes redundancy mechanisms in the infrastructure. Differential sensitivity analysis was applied to identify and rank the critical components of the system with respect to service availability. The results demonstrate that such a modeling strategy combined with differential sensitivity analysis can be an attractive methodology for identifying which components should be supported with redundancy in order to consciously increase system dependability

Mars spacecraft power system development Interim report

Modified Mariner power system design for Mars mission

Performance Evaluation of the Multi-winding Redundancy Approach in MTB DC-DC Converters

The Multi-winding transformer-based (MTB) DCDC converter topologies have been investigated to be applied as the key component in different application fields, in particular those which are safety-critical ones, such as aerospace, energy distribution, and data-centers (data-processing). Thus, this paper presents a fault-tolerance concept associated with the possibility of operating the MTB topologies even under fault conditions, by only disconnecting the faulty cell and keeping the healthy ones operating continuously. In this approach, named Multi-winding redundancy (MWRed), the MTB converter is equipped with additional isolation switches which enhance its fault-tolerant capability. In contrast to competing approaches, MWRed utilizes the magnetic coupling of the MWT to reduce the use of several redundancies, which makes the strategy more appealing in critical applications. Further, in order to evaluate the impact of the isolation switches on MTB converters, the MWRed is assessed in terms of efficiency and reliability, so that the superior advantages to conventional approaches are presented and demonstrated. Finally, the investigated MWRed is evaluated experimentally to validate its effectiveness in different scenarios

Fault-tolerant computer study

A set of building block circuits is described which can be used with commercially available microprocessors and memories to implement fault tolerant distributed computer systems. Each building block circuit is intended for VLSI implementation as a single chip. Several building blocks and associated processor and memory chips form a self checking computer module with self contained input output and interfaces to redundant communications buses. Fault tolerance is achieved by connecting self checking computer modules into a redundant network in which backup buses and computer modules are provided to circumvent failures. The requirements and design methodology which led to the definition of the building block circuits are discussed