Title : ANALYSIS FOR THE RELIABILITY OF THE INTRINSIC BASE ION IMPLANTATION OF A 3 GHZ I(2)L BIPOLAR PROCESS FROM THE MEASURE OF INTEGRATED RESISTANCES - FROM THE RESULTS, SETTING OF RULES FOR AN EXPERT SYSTEM

Authors : Loheac JL. Raoult F. Bonnaud O. Taurin M.

Source : Microelectronics & Reliability. 37(1):179-186, 1997 Jan.

ISSN : 0026-2714

To avoid a shift of the process parameters during various steps of wafer manufacturing, it is important to monitor them, daily and quicker as possible. At parametric facility, testing devices of the wafer are electrically characterized to make a critical checking of the process. For the case of a 3 GHz bipolar technology, we have defined rules for the monitoring of the dose and of the energy of a critical ion implantation and for the control of the thickness variation of a thin LOGOS. The analysis is based on the measurement of three types of integrated resistances. Also, to write and to validate the rules, we did a process analysis with a tool called Failure Modes and Effects Analysis (FMEA), which allowed us to predict the effects of these parameters on the electrical characteristics. Following this study, we realise a Design Of Experiment (DOE). From the results, and based on a simple process monitoring method, specific rules are written to be inserted in a technological expert system for the failure of the intrinsic base ion implantation during the fabrication process. Copyright (C) 1996 Elsevier Science Ltd

Number of References : 9

Language : English

Reprint available from: Loheac JL,; SGS THOMSON MICROELECT, 4 RUE SUISSE , F-35000 RENNES FRANCE

Title : INTEGRATED RELIABILITY ANALYSIS SYSTEM (IRAS)

Authors : Kocza G. Bossche A.

Source : Quality & Reliability Engineering International. 12(5):371-381, 1996, Sep-Oct.

ISSN : 0748-8017

Keywords : Hierarchical modelling. Fault tree generation. Fmeca. Real time fault location, Fault tree synthesis.

This paper will introduce a computer aided reliability analysis system, IRAS, which is a Unix-based software package. It provides the following features: a model builder, failure mode effect and criticality analysis (FMECA), fault tree synthesis and analysis (FTA) and real time fault location (RTFL).

1. The model builder allows the creation of reliability models for production systems, which are able to reflect the initiation and propagation of serious deviations outside the production and performance tolerances. The modelling procedure allows hierarchical modelling.
2. The failure mode effect and criticality analysis (FMECA) option uses the causal trees and cause-consequence diagrams that are created automatically from the IRAS model data base. The trees can be analysed by the user and the basic events can be grouped according to their criticality, probability and severity.
3. The fault tree analysis and synthesis (FTA) option enables the graphical analysis of fault trees. The generated tree can be trimmed automatically or by the user. It is also possible to extract the minimal cut-set from the complete tree.
4. RTFL enables the fast detection of the most probable fault locations in the system, during the continuous measuring of sensors of the production system and comparing the signals with the expected values of the stored operational vector. It alarms the user in case of serious deviations, thus reducing the out of work stage of the system by making quicker and more efficient reaction of the maintenance facility operators. The failure searching time reduction results in lower maintenance cost.

Number of References : 5

Language : English

Reprint available from: Kocza G, DELFT UNIV TECHNOL, FAC ELECT ENGN, 4 MEKELWEG NL-2628 CD DELFT NETHERLANDS

Title : A RELIABILITY CENTERED MAINTENANCE STRATEGY FOR A DISCRETE PART MANUFACTURING FACILITY

Authors : Pujadas W. Chen FF.

Source : Computers & Industrial Engineering. 31(1-2):241-244, 1996 Oct.

ISSN : 0360-8352

Keywords : Reliability centered maintenance (rcm). Maintenance planning. Performance measures. Failure analysis.

A specialized maintenance decision support system based on Reliability Centered Maintenance (RCM) and the US dept. Of Defense's Failure Mode. Effect and Criticality Analysis (FMECA) has been developed. It was constructed using a modular approach which uniquely integrates the virtues of RCM and FMECA to perform the failure analysis function. A Logic Tree Analysis (LTA) module supports the decision process by performing Cost and Maintainability evaluation to promote the most appropriate maintenance tasks. The Maintenance Planning Module applies ''Theory of Constraints'' to fit tasks into the production schedule. Apart from a conventional focus on addressing operational failure modes, it takes environmental impact and human safety concerns into perspective in developing tasks; directed at achieving higher levels of equipment availability and effectiveness Ultimately, it contributes to higher quality product manufactured at a significantly lower overall cost. Initial field test results for Miami, Florida based manufacturing system are reviewed.

Number of References 10

Language : English

Reprint available from: Pujadas W FLORIDA INT UNIV DEPT IND & SYST ENGN UNIV PK ECS 442 MIAMI, FL 33199 USA

Title : HANDLING UNCERTAINTY WITH POSSIBILITY THEORY AND FUZZY SETS IN A SATELLITE FAULT DIAGNOSIS APPLICATION

Authors : Cayrac D. Dubois D. Prade H.

Source : IEEE Transactions on Fuzzy Systems. 4(3):251-269, 1996 Aug.

ISSN : 1063-6706

The fault mode effects and criticality analyses (FMECA) describe the impact of identified faults. They form an important category of knowledge gathered during the design phase of a satellite and are used also for diagnosis activities, This paper proposes their extension, allowing a finer representation of the available knowledge, at approximately the same cost, through the introduction of an appropriate representation of uncertainty and incompleteness based on Zadeh's possibility theory and fuzzy sets, The main benefit of the approach is to provide a qualitative treatment of uncertainty where we can for instance distinguish manifestations which are more or less certainly present (or absent) and manifestations which are more or less possibly present (or absent) when a given fault is present, In a second step, the proposed approach is extended to handle fault impacts expressed as event chronologies, Efficient, real-time compatible discrimination techniques exploiting uncertain observations are introduced, and an example of satellite fault diagnosis illustrates the method. A brief rationale for the choice of possibility theory and fuzzy sets is provided. Besides, the proposed approach is related to the logical view of diagnosis.

Number of References : 35

Language : English

Reprint available from: Cayrac D HEWLETT PACKARD FRANCE F-38053 GRENOBLE 09 FRANCE

Title : KNOWLEDGE-BASED SUPPORT OF SYSTEM ANALYSIS FOR THE ANALYSIS OF FAILURE MODES AND EFFECTS

Authors : Wirth R. Berthold B. Kramer A. Peter G.

Source : Engineering Applications of Artificial Intelligence. 9(3):219-229, 1996 Jun.

ISSN : 0952-1976

Keywords : Functional model. Failure mode and effects analysis. Quality assurance. Taxonomies. System analysis. Design.

Failure mode and effects analysis (FMEA) is an important method of preventive quality assurance However, even 30 years after its introduction in the aerospace industry and despite more than 10 years of experience in using this method in development, FMEA is still a challenge for many companies. This paper analyses the problems with the conventional way of carrying out an FMEA. It is argued that a knowledge-based approach to FMEA can alleviate most of these problems. The solution chosen in the WIFA project is presented. WIFA employs various knowledge bases to support complete and precise descriptions of processes and products, and to facilitate the later reuse of the knowledge collected during an FMEA. The essential features of these knowledge bases, and their use in FMEA, are described. Copyright (C) 1996 Elsevier Science Ltd

Number of References : 12

Language : English

Reprint available from: Peter G FAW ULM HELMHOLTZSTR 16 D-89081 ULM GERMANY

Title : UNCERTAINTY ANALYSIS IN QUANTITATIVE RISK ASSESSMENT

Authors : Quin S. Widera GEO.

Source : Journal of Pressure Vessel Technology-Transactions of the ASME.118(1):121-124, 1996 Feb.

ISSN : 0094-9930

Of the quantitative approaches applied to inservice inspection, failure modes, effects, criticality analysis (FMECA) methodology is recommended. FMECA can provide a straightforward illustration of how risk can be used to prioritize components for and inspection (ASME, 1991). But, at present, it has two limitations. One is that it cannot be used in the situation where components have multiple failure modes. The other is that it cannot be used in the situation where the uncertainties in the data of components have nonuniform distributions. In engineering practice, these two situations exist in many cases. In this paper, two methods based on fuzzy set theory are presented to treat these problems. The methods proposed here can be considered as a supplement to FMECA, thus extending its range of applicability.

Number of References : 7

Language : English

Reprint available from: Quin S MARQUETTE UNIV DEPT MECH & IND ENGN 1515 W WISCONSIN AVE MILWAUKEE, WI 53233 USA

Title : USING FUZZY COGNITIVE MAPS AS A SYSTEM MODEL FOR FAILURE MODES AND EFFECTS ANALYSIS

Authors : Pelaez CE. Bowles JB.

Source : Information Sciences. 88(1-4):177-199, 1996 Jan.

ISSN : 0020-0255

This paper explores the application of Fuzzy Cognitive Maps (FCM) to Failure Modes and Effects Analysis (FMEA). FMEAs are used in reliability and safety evaluations of complex systems to determine the effects of component failures on the system operation. FCMs use a digraph to show cause and effect relationships between concepts; thus, they can represent the causal relationships needed for the FMEA and provide a new strategy for predicting failure effects in a complex system.

Number of References : 16

Language : English

Reprint available from: Pelaez CE UNIV S CAROLINA DEPT ELECT & COMP ENGN COLUMBIA, SC 29208 USA

Title : DESIGNING FOR QUALITY - AN INTEGRATED APPROACH FOR SIMULTANEOUS QUALITY ENGINEERING

Authors : Braunsperger M.

Source : Proceedings of the Institution of Mechanical Engineers Part B-Journal of Engineering Manufacture. 210(1):1-10, 1996.

ISSN : 0954-4054

Keywords : Quality control. Product quality. Quality assurance. Q steps. Quality control list. Pas principle. Integration factor.

Automoble industry practice has shown that it is not sufficient merely to apply familiar quality control methods such as FMEA (failure mode and effects analysis) or QFD (quality function deployment), to introduce development process (DP) systems or to adopt project management procedures when an improvement in product quality is required. More than this has to be done: the product development procedure must be better nl ranged and made capable of achieving preventive quality assurance. This paper presents an all-areas quality assurance concept as drawn up in the body development area of the BMW AG company and implemented successfully in the course of several pilot projects prior to general introduction. It is intended to provide stimuli and encouragement for similar measures to be taken in other areas, for example in the machinery construction industry.

Number of References : 8

Language : English

Reprint available from: Braunsperger M BMW AG DINGOLFING PLANT MUNICH GERMANY

Title : FACILITY RISK REVIEW AS A MEANS TO ADDRESSING EXISTING RISKS DURING THE LIFE CYCLE OF A PROCESS UNIT, OPERATION OR FACILITY

Author : Schlechter WPG.

Source : International Journal of Pressure Vessels & Piping. 66(1-3):387-402, 1996.

ISSN : 0308-0161

In today's process industry environment, it is becoming more and more important for companies to manage the risks associated with their plants. Amongst others, some reasons for this are that 1) Process Safety is featuring high on the agenda of Trade Unions; 2) that Management is coming under increased pressure to provide a safe workplace; 3) that Companies are trying to survive in the current competitive environment by adopting the ''zero accidents'' ideal; 4) because the effects of accidents that do occur are becoming more devastating due to increased inventories and the exotic nature of products and 5) the fact that overseas companies are looking at safety and conservation track records before choosing business partners or considering trade agreements. Regulatory directives such as OHSA'S (Occupational Health and Safety Act, Act 85 of 1993) Major Hazard Installation Regulation in conjunction with SABS 0228 (hazard group 1)(1) is another newcomer entering the playing fields of South African Companies and is in the future going to have a serious impact on Company philosophies and policies. In this Regulations ''Risk Assessment'' is defined as ''a planned programme to reduce, to remove, and to control a major incident''. This can be interpreted as having the meaning/objective to involve some type of Risk Management programme which will co-ordinate inter alia the risk assessment function. Also defined is ''Major Incident'', which reads: ''It is an occurrence (including in particular, a major emission, fire or explosion) resulting from uncontrolled developments in the course of an industrial activity, leading to a serious danger to persons, whether immediate or delayed, inside or outside the installation, or to the environment, and involving one or more dangerous substance'' To address this problem of managing the risks in a facility/plant/operation is no mean feat. Cost factors, time constraints, manpower availability, legislatory pressures and uncertainty on the most applicable risk assessment method to use, are just some of the problems facing management. Adding to this dilemma is the fact that the reviewing specialist has to choose from a variety of risk assessment methods that have varying degrees of complexity, cost and applicability.(2) Past experience has however shown that Hazard and Operability Analysis (Hazop), Failure Mode and Effects Analysis (FMEA), Fault Tree Analysis and Event Tree Analysis are the most widely used and well accepted. Choosing the right assessment method which will provide the information management needs to address the facility's risks is often the most difficult part in the whole assessment process. With this paper we are providing an overview of such a risk assessment method, namely Facility Risk Review (FRR) which uses a combination of techniques of a qualitative and quantitative nature. These methods are similar to those currently being used with great success in the risk assessment process at the facilities of the Sasol Group of Companies. These methods are in use from the initial conceptual design stage of any project or change up to the stage where the facility has been in operation for many years.

Number of References : 4

Language : English

Reprint available from: Schlechter WPG SASOL SYNTHET FUELS PROC SAFETY POB 1 IB 2750 SECUNDA 2302 SOUTH AFRICA

Title : DESIGN FOR SAFETY OF ENGINEERING SYSTEMS WITH MULTIPLE FAILURE STATE VARIABLES

Authors : Wang J. Ruxton T. Labrie CR.

Source : Reliability Engineering & System Safety. 50(3):271-284, 1995.

ISSN : 0951-8320

Since possible failure events of large engineering systems with a higher level of innovation may not be identified by experience or from previous accidents and incident reports of similar systems, and since 'design for safety' of such systems requires no omission of failure causes associated with possible system failure events, a top-down approach is not always satisfactorily applied in the risk identification and risk estimation phases and a more objective and flexible bottom-up approach may be more effective. This paper proposes an inductive bottom-up risk identification and estimation methodology combining Failure Mode, Effects and Criticality Analysis (FMECA) and the Boolean Representation Method (BRM). This methodology can be used to identify all possible system failure events and associated causes, and to assess the probabilities of occurrence of them particularly in those cases where multiple state variables and feedback loops are involved. The Boolean representation method is presented together with its use in modelling cause and effect relationships. The overall model and the algorithms are described and tested in association with the associated computer software. The applications of this methodology in association with other formal safety modelling methods are discussed. An illustrative example is presented to demonstrate the methodology.

Number of References : 22

Language : English

Reprint available from: Wang J LIVERPOOL JOHN MOORES UNIV SCH ENGN & TECHNOL MANAGEMENT LIVERPOOL L3 3AF MERSEYSIDE ENGLAND

Last update March 21, 2000