3.4 Software groups
3.4.10 Tool control software
Tool control software tools track vital assets and tools, providing a detailed audit trail for check in/check out, minima and maxima for ordering, and calibration tracking with detailed history, issue and return functions, inventory and ordering, re-work, kit building etc. Some widely used examples: Automated Tool Inventory Control and Tracking System, collectiveTool Crib, ToolHound, CribMaster Inventory Management System, ToolManager TLC32 Pro.
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The role of CAPE tools is crucial for the analysis of failure data in Reliability, Availability, Maintainability and Safety (RAMS). In waste management, a wide variety of failures has big influence to the correct consideration of failure data. In addition, scheduled outages such as cleaning, supervision, avoidance of fatigue, although not caused by failures, need to be considered too. Some data are difficult to collect and rather sensitive. Collected data should be analysed in many ways. An efficient CAPE approach in this field is to apply a combination of reliability and waste management software packages for the related analyses, calculations and predictions, considering the specificities of waste management failure data.
Some reliability software tools are capable to solve specific problems only. In contrast, complex RAMS packages integrate various modules providing availability, reliability and maintenance services, including:
• Availability Simulation, availability predictions
• Failure Mode Effects and Criticality Analysis (FMECA)
• Reliability Block Diagram (RBD)
• Fault Tree Analysis (FTA)
• Event Tree Analysis (ETA)
• Markov Analysis (MKV)
• Life Cycle Cost (LCC) Analysis
• Reliability prediction
• Maintainability prediction
Some companies offer their software tools both as integrated modules of RAMS packages and separate software tools that can be purchased individually (e.g. ReliaSoft).
Although there is a wide variety of software on the market, it is recommended to use a complex reliability software package for optimisation problems dealing with large amounts of data. Further benefits of these programs are the capability of modelling via various methods and tools, the high accuracy of results, among the possibility to use other helpful features.
Lots of problems can be solved by most of the complex reliability software packages, but in different ways. The main reason to take a closer look at these products is that they contain different modules. In the following sections, an assessment will be made on some promising software suits.
3.4.11.1 Relex Reliability Studio
One of the most promising reliability software packages is Relex Reliability Studio (Relex Software Corporation, 2009b). An example of the workscreen of this software package is presented in Fig. 3.6.
To become familiar with the modules provided by the program, the user should simply execute it. Modules can be selected in the first modal window that appears before the main working screen of Relex Reliability Studio. These modules are: Event Tree, Fault Tree, FMEA, FRACAS, Human Factors, Life Cycle Cost, Maintainability, Markov, Phase Diagrams, Reliability Prediction, RBD-OpSim, Weibull.
The following integrated modules are also available as standalone products:
• Relex: Availability, Reliability & Maintainability Analysis Software
• Relex Event Tree: Relex Event Tree enables the user to easily create complete event trees and perform fast and accurate calculations. It quickly computes the probabil-ity of all the possible outcomes, as well as for the events leading up to them. Relex Event Tree can display the unavailability, unreliability, frequency, availability, and reliability of the undesired event. It creates customizable reports, showing the complete analysis or specific branch data.
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Figure 3.6 Working screen of Relex Reliability Studio.
• Relex Fault Tree: Relex Fault Tree lets the user easily create customizable fault tree diagrams and perform fast and accurate system safety analyses. It offers both graphical and tabular displays, making it easy to edit specific gate properties. Relex Fault Tree supports numerous gate and event types, common cause failure modelling, time dependent analyses, and includes a Minimal Cut Set engine.
• Relex FMEA/FMECA: Relex FMEA/FMECA can handle Failure Mode, Effects and Criticality Analyses with unsurpassed power and flexibility. It supports the FMEA standards developed by the aerospace, defense, and automotive industries, and enables customization. Relex FMEA/FMECA supports risk priority numbers (RPN), criticality ranks, risk levels, criticality matrices, failure mode probability calculations, and exporting to LSAR compatible formats.
• Relex Life Cycle Cost: Relex LCC is a flexible Life Cycle Cost analysis tool that calculates the cost of any product over its lifetime. By taking inflation factors into account, users can easily explore various alternatives. Its features include a user-definable Cost Breakdown Structure (CBS), built-in equation editor, net present value (NPV) calculations, sensitivity analyses, and defining time intervals and various alternatives.
• Relex Maintainability Prediction: Relex Maintainability Prediction provides a solid framework for performing maintainability analyses. It calculates numerous mainte-nance parameters, including various mean times. Relex Maintainability Prediction is based on the MIL-HDBK-472 Procedures 2, 5A and 5B, the accepted standards for maintainability predictions.
• Relex Markov: Relex Markov provides powerful state-based system analysis. It uses the failure and transition rates between states to determine the reliability, availability, MTBF, MTTR, failure frequency, and other mission-critical statistics of
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the system. Relex Markov significantly enhances traditional reliability analysis tools when studying systems with common cause failures, degradation, multi-operational state components, and other sequence-dependent events.
• Relex RBD: Relex Reliability Block Diagram enables the user to create complex and illustrative system diagrams. It allows complete customization of images, fonts, sizing, and colors. Relex RBD performs a host of reliability calculations, and includes a powerful Monte Carlo simulation engine and a spare optimisation algorithm.
• Relex Reliability Prediction: The Relex Reliability Prediction Engine evaluates failure rate and MTBF values, performs reliability allocation calculations, pinpoints areas for reliability improvement, and provides professional graphical and tabular output.
It supports the most current reliability standards, including MIL-HDBK 217, Telcordia (Bellcore) SR-332, PRISM, CNET 93, and more.
Each of the above mentioned modules can be used separately or simultaneously. This is a common feature of many RAMS software packages.
The program supports various static gate types (AND, OR, voting, XOR, NAND, NOR, NOT, Inhibit, Transfer, Remarks, Pass-through) as well as dynamic ones (Priority AND, Functional dependency, Sequence enforcing, Spare). Basic, Spare, House, Undeveloped and Conditional event types can be used. Reliability Studio offers various calculation methods for unreliability, unavailability, frequency of failures, number of failures, cut sets, and importance measures. Fault trees can be represented either in tabular or graphical view. There are many opportunities to produce various outputs, including graphical diagram, event importance, minimal cut sets, unreliability/reliability vs. time, unavailability/availability vs. time, gate/event results, and failure frequency vs. time. Very useful features of this software package are the data linkages between the event tree, the fault tree, FMEA, Markov, and Reliability Prediction.
Relex Software Corporation provides a fully functional demo version with limited number of components for evaluation.
3.4.11.2 ITEM Toolkit
ITEM Toolkit (ITEM Software, 2009) is an integrated reliability analysis and safety software tool (Fig. 3.7).
It consists of predictive and analytical modules, including:
• Reliability prediction
• Failure Mode, Effects and Criticality Analysis (FMECA)
• Reliability Block Diagram (RBD)
• Fault Tree Analysis (FTA)
• Event Tree Analysis (ETA)
• Markov analysis
• Maintainability
• Spares Scaling and Ranging
ITEM Toolkit is especially suitable for comprehensive analysis of reliability, availability, maintainability and safety of electrical, as well as mechanical components of systems. It is an integrated package for scalable analysis.
The company offers further tools as well. ITEM QRAS is a quantitative risk assessment system. ITEM QT is a customizable, cross-platform reliability/risk project and analysis framework.
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Figure 3.7 Editing a Fault Tree in ITEM Toolkit.
ITEM ToolKit consists of several modules, including the following ones.
• BellCore Module. The ITEM ToolKit Bellcore module is based on the internationally recognized Reliability Prediction Standard Telcordia (Bellcore) TR-332 Issue 6 and SR-332 Issue 1. This module calculates Failure Rates and MTBFs of Electronic Components and is a fully integrated module of ITEM ToolKit.
• CHINA 299B Module. The ITEM ToolKit CHINA 299B module is based on the internationally recognized Reliability Prediction Standard CHINA 299B, Chinese Military Standard. This module calculates Failure Rates and MTBFs of Electronic Components and is a fully integrated module of ITEM ToolKit.
• FaultTree Module. The ITEM ToolKit FaultTree module is a powerful fault tree diagram module which uses efficient minimal cut set generation routines to analyse large and complex Fault Trees. This module is particularly adept in predicting safety, reliability and availability parameters for system hazards and is a fully integrated module of ITEM ToolKit.
• MainTain Module. The ITEM ToolKit MainTain module provides an integrated environment to predict the expected number of hours that a system or device will be in an inoperative or “down state” while it is undergoing maintenance. MainTain utilises techniques specified in MIL-HDBK-472 Method A to predict maintainabil-ity in quantitative terms. This is a fully integrated module of ITEM ToolKit.
• Markov Module. The ITEM ToolKit Markov module uses Markov Analysis techniques to analyse state transition diagrams. The Markov module provides the reliability and availability analyses of systems whose components exhibit strong dependencies. Other analysis methods assume component independence, which
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may lead to optimistic results. The Markov Module is a fully integrated module of ITEM ToolKit.
• Mechanical Module. The ITEM ToolKit Mechanical module is based on the internationally recognized Reliability Prediction Standard NSWC 98/LE1. This module calculates Failure Rates and MTBFs of Mechanical Components and is a fully integrated module of ITEM ToolKit.
• MIL-217 Module. The ITEM ToolKit MIL-217 module is based on the internationally recognized Reliability Prediction Standard MIL-HDBK217. This module calculates Failure Rates and MTBFs of Electronic Components and is a fully integrated module of ITEM ToolKit.
• RBD Module. The ITEM ToolKit RBD module is a powerful systems reliability analysis tool, which allows reliability block diagram (reliability network) analysis to be performed for Unavailability studies. This is a fully integrated module of ITEM ToolKit and is capable to analyse large and complex reliability block diagrams.
• RDF Module. The ITEM ToolKit RDF module is based on the internationally recognized Reliability Prediction Standard RDF 2000 UTE C 80-810, French Telecommunication Standard. This module calculates Failure Rates and MTBFs of Elctronic Components and is a fully integrated module of ITEM ToolKit.
3.4.11.3 Isograph Reliability Workbench
Reliability Workbench (Isograph Ltd., 2009) provides different analysing techniques, including reliability prediction, FMECA, maintainability prediction, reliability block diagram analysis, reliability allocation, fault tree analysis, event tree analysis, and Markov analysis.
Here is a quick overview of the modules of this fully integrated environment:
• Failure Rate Prediction. Failure rate prediction is one part of the Reliability Workbench package. All failure rate prediction methods have the same general form. They provide a powerful visual interface through which the user can select components and define the conditions in which they operate such as the temperature or environmental conditions. The prediction software then carries out the failure rate calculation as defined by the standard and gives the result. The MIL-217, Telcordia (Bellcore), RDF 2000 and GJB/Z 299B are mainly for electronic components and the NSWC handbook deals with mechanical components.
• Fault Tree and Event Tree Analysis. This Reliability Workbench module provides CCF analysis, importance analysis, uncertainty and sensitivity analysis facilities. The program allows users to construct a single project database containing generic data and event tables, multiple fault trees, event trees originating from different initiating events, CCF tables and consequence tables. Fault and event tree pagination is automatically controlled by the program. Fault tree top events may be used to represent specific nodes in the event tree. Multiple branches are also allowed to handle partial failures.
FaultTree+ uses efficient minimal cut set generation algorithms to analyse large and complex fault and event trees. Negation may be included in the fault and event trees at any level and event success states retained in the analysis results as an option. The program also includes integrated event tree and Markov analysis modules. Powerful reporting, charting and import/export facilities are also included.
• FMECA. This Reliability Workbench module allows one to carry out a FMECA in a familiar visual environment with minimum effort. When FMECA information is entered, the software is capable to produce high quality reports. The FMECA module may be used to perform a MIL-STD-1629 FMECA, a Process or Design FMEA and other customised formats.
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The following modules are also parts of the Reliability Workbench:
• GJB/z 299B. This module provides a powerful visual interface to input data and calculate failure rates according to GJB/Z 299B.
• Markov Analysis. This module analyses state transition diagrams (markov chain) using numerical integration techniques. It provides facilities for defining multiple phases representing continuous or discrete transitions. The module also analyses non-homogeneous processes by allowing the definition of time-dependent transition rates.
Systems with time-dependent transition rates are strictly non-Markovian. However, the addition of this facility allows the modelling of certain types of ageing processes.
• MIL-STD-217. This module of Reliability Workbench provides a powerful visual interface for input data and calculate failure rates according to MIL-STD-217.
• NSWC. This module provides a powerful visual interface to input data and calculate failure rates according to NSWC
• RBD Software. This module is a sophisticated yet easy to use program that allows the user to easily create reliability block diagrams in a visual environment. This module provides an analytical solution to reliability problems posed as Reliability Block Diagrams. It can analyse large and complex RBDs and produce a minimal cutset representation and a wide range of quantitative parameters such as unavailability, unreliability, expected downtime and expected number of failures. The RBD analysis module also gives the results of importance and house event analysis.
• RDF 2000. This module provides a powerful visual interface to input data and calculate failure rates according to RDF 2000.
• Telcordia (Bellcore). This module provides a powerful visual interface to input data and calculate failure rates according to Telcordia (Bellcore).
These modules are interconnected. The links between them are maintained and data can be automatically updated in one module due to changes made in another. Data can be easily transferred between the different parts of the software tool by automatic data transfer or copy/paste. It is Access and Excel compatible.
The developer company provides a demo version with project size and saving limitations for evaluation purposes.
3.4.11.4 ReliaSoft BlockSim
BlockSim is a comprehensive platform developed by ReliaSoft (ReliaSoft Corporation, 2009a). It provides system reliability, availability, maintainability and related analyses, e.g.
reliability optimisation, throughput, resource allocation, and life cycle cost.
A wide set of RBD configurations and FTA gates (Fig. 3.8) as well as events are supported, including advanced capabilities to model complex configurations, load sharing, standby redundancy, phases, and duty cycles.
Both computations and/or discrete event simulation can be used. BlockSim supports both repairable and non-repairable system analyses.
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Figure 3.8 A Fault Tree in ReliaSoft BlockSim.
3.4.11.5 BQR CARE
Computer Aided Reliability Engineering (CARE) is a set of software tools capable to simulate all kinds of system failures and the effects of such failures on system behaviour (BQR Reliability Engineering, 2009). CARE can efficiently contribute to the development of more reliable systems, with cost effective hardware, considering design time. It simulates all potential functional and process failures, including electrical, electronic, mechanical and software failures. If high availability is desired, CARE can recommend the optimal redundancy that is needed to achieve the highest availability at a minimum hardware cost.
It can be used in the preliminary design as top-down allocation or analysis and in the full-scale development as a bottom-up prediction/analysis.
The software package integrates well-known design CAD/CAE system approaches and uses the data in real time when generated by the designer in order to shorten the design cycle.
The list of modules contains, but not limited to, MTBF prediction and allocation, FMEA/FMECA, FTA, MTTR, and RBD.
3.4.11.6 MEADEP
MEADEP (Measurement-based Dependability Analysis Tool) is a combination of reliability and availability prediction modelling tools, as well as statistical analysers. It is capable to calculate availability, MTBF, MTTR, failure rate, recovery rate, and reliability of both repairable and non-repairable systems. MEADEP is compatible with various databases, including Oracle, dBASE, FoxPro, and Paradox. It calculates confidence intervals and fit parameters to probability distributions (e.g. exponential, Weibull, gamma, normal and lognormal). Cluster analysis allows identify potentially correlated events. MEADEP provides comprehensive features:
• Drag and drop model builder. It is capable to model both simple and parallel block diagrams and sophisticated Markov models or their combination.
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• Hierarchical models. Complex systems can be broken to smaller and more manageable subsystem models.
• Model libraries. They enable the creation, sharing or re-use of existing models of similar design or method developments. MEADEP has several built-in templates for various kinds of series, parallel, redundant, and non-redundant systems.
• Trade-off studies and parametric analyses. The model evaluator can be used not only for single models, but for parametric analyses dealing with single parameters or parameter sets.
MEADEP produces exportable numerical, as well as graphical results for reliability analysis reports.
• Special features for large reusable models. Complete documentation, parametric and sensitivity analyses, comment entry, total flexibility in alternate value set selection.
• Output on spreadsheets. A very useful feature of MEADEP is the capability to present results directly on spreadsheets. Furthermore, they can be exported to Microsoft Excel for post-processing.
The developer, SoHaR Inc., provides a demo version with model size limitations (SoHaR Incorporated, 2009).
3.4.12 Life cycle assessment software
The LCA approach is recommended in several recent pieces of european legislation on waste (and in the future waste framework directive). Several software tools have been developed as for example the WISARD software (Clift et al., 2000). Further examples are the SIMA PRO tool and the more recent EASEWASTE tool (Kirkeby et al., 2006) that represent the effort to design flexible tools for comparing different waste management strategies.
3.4.13 Life cycle cost modelling software
A quick overview of life cycle cost modelling software can be made by investigating a typical example. CAME-LCC is capable to calculate full cost for each life cycle phase, including investment, development, production, delivery, operation and disposal.
Furthermore, total life cost can be calculated using user data or the recommendations of the CAME optimisation modules (BQR Reliability Engineering Ltd., 2009). Cost results and options can be considered for various scenarios, i.e. CAME-LCC helps to choose the appropriate scenario or define new ones.
Reliability vs. availability can be presented. Both one level and multi-level systems can be handled. It provides united trade-off table and graph for result comparisons. The software is capable to generates a wide range of reports, including summary, detailed, Pareto (sorted by cost drivers) and input data. Each report can be generated by years as total values. Pareto and detailed reports are effective for analytical purposes.
3.4.14 Environmental decision support software
In the last few decades, mathematical and statistical models, numerical algorithms and computer simulations have been used as the appropriate means of the investigation of environmental management problems and the way to provide useful information to engineers.
To this end, a wide set of scientific techniques have been applied to environmental
To this end, a wide set of scientific techniques have been applied to environmental