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Open Access
Article
Publication date: 28 June 2022

Wenhao Yu, Jun Li, Li-Ming Peng, Xiong Xiong, Kai Yang and Hong Wang

The purpose of this paper is to design a unified operational design domain (ODD) monitoring framework for mitigating Safety of the Intended Functionality (SOTIF) risks triggered…

1487

Abstract

Purpose

The purpose of this paper is to design a unified operational design domain (ODD) monitoring framework for mitigating Safety of the Intended Functionality (SOTIF) risks triggered by vehicles exceeding ODD boundaries in complex traffic scenarios.

Design/methodology/approach

A unified model of ODD monitoring is constructed, which consists of three modules: weather condition monitoring for unusual weather conditions, such as rain, snow and fog; vehicle behavior monitoring for abnormal vehicle behavior, such as traffic rule violations; and road condition monitoring for abnormal road conditions, such as road defects, unexpected obstacles and slippery roads. Additionally, the applications of the proposed unified ODD monitoring framework are demonstrated. The practicability and effectiveness of the proposed unified ODD monitoring framework for mitigating SOTIF risk are verified in the applications.

Findings

First, the application of weather condition monitoring demonstrates that the autonomous vehicle can make a safe decision based on the performance degradation of Lidar on rainy days using the proposed monitoring framework. Second, the application of vehicle behavior monitoring demonstrates that the autonomous vehicle can properly adhere to traffic rules using the proposed monitoring framework. Third, the application of road condition monitoring demonstrates that the proposed unified ODD monitoring framework enables the ego vehicle to successfully monitor and avoid road defects.

Originality/value

The value of this paper is that the proposed unified ODD monitoring framework establishes a new foundation for monitoring and mitigating SOTIF risks in complex traffic environments.

Details

Journal of Intelligent and Connected Vehicles, vol. 5 no. 3
Type: Research Article
ISSN: 2399-9802

Keywords

Article
Publication date: 8 October 2018

Jim Townsend and M. Affan Badar

Reciprocating compressors offer an efficient method of compressing almost any gas composition in a wide range of pressures and have numerous applications. Condition monitoring of…

Abstract

Purpose

Reciprocating compressors offer an efficient method of compressing almost any gas composition in a wide range of pressures and have numerous applications. Condition monitoring of critical rotating machinery is widely accepted by operators of centrifugal compressors. However, condition monitoring of reciprocating machinery has not received the same degree of acceptance. An earlier study (Townsend et al., 2016) was conducted on temperature monitoring. The purpose of this paper is to examine the impact of continuous pressure monitoring on electric-driven compressors.

Design/methodology/approach

This research analyzes the impact of continuous pressure monitoring on a fleet of 14 compressors transporting CO2 for enhanced oil recovery. The reliability and efficiency data on 14 reciprocating compressors over a three-year period were analyzed for failures detectable by the condition monitoring technology. The engineering economic analysis is presented to determine the impact this technology will have on the productivity of the compressors.

Findings

The study considers utilizing condition monitoring technology to analyze the pressure of the swept volume of the compressor cylinders. The results of the study indicate that continuous pressure monitoring technology has a strong impact on the productivity of the compressor fleet. The internal rate of return not only exceeds the operators hurdle rate, but the payback period is also dramatic. Pressure monitoring was found to be economically better than temperature monitoring.

Originality/value

The study reveals the economic benefits of implementing condition monitoring in the form of continuous pressure monitoring on reciprocating compressors.

Details

Journal of Quality in Maintenance Engineering, vol. 24 no. 4
Type: Research Article
ISSN: 1355-2511

Keywords

Article
Publication date: 19 December 2016

Amy E. Green, Guy Cafri and Gregory Aarons

The concerns that implementing a new structured innovation with increased oversight may lead to reduced job autonomy and poorer work attitudes. These concerns have been cited as a…

Abstract

Purpose

The concerns that implementing a new structured innovation with increased oversight may lead to reduced job autonomy and poorer work attitudes. These concerns have been cited as a barrier to evidence-based treatment (EBT) implementation. However, previous research found lower turnover among child welfare providers implementing an EBT with fidelity monitoring compared to those administering services as usual (SAU). The authors hypothesized that changes in job autonomy, job satisfaction, and organizational commitment would be no worse among providers in EBT conditions and fidelity monitoring conditions compared to SAU and no monitoring conditions.

Design/methodology/approach

Survey data were collected from 208 service providers over four waves at six month intervals as part of a 2 (EBT vs SAU) by 2 (fidelity monitoring vs no monitoring) hybrid effectiveness-implementation trial. Superiority testing was conducted to determine whether there were significant differences over time on the outcomes as a function of experimental condition. Non-inferiority testing examined whether the EBT condition is not inferior to SAU and monitoring not inferior to no monitoring on the outcomes.

Findings

No evidence of superiority was found for any conditions over time on the outcomes. Non-inferiority testing indicates EBT is not inferior to SAU and monitoring is not inferior to no monitoring on the outcomes.

Originality/value

This study provide empirical quantitative data regarding job attitudes and job autonomy perceptions over time following EBT implementation. In light of the current findings, concerns regarding the impact of EBT implementation on provider job perceptions should be minimized.

Details

Journal of Children's Services, vol. 11 no. 4
Type: Research Article
ISSN: 1746-6660

Keywords

Article
Publication date: 28 October 2013

Zheng Hong and YiHai Zhou

Faced with the financing problem of small-medium enterprises (SMEs), China has attempted to establish as many as third party's collateral institutions. The paper aims to study the…

Abstract

Purpose

Faced with the financing problem of small-medium enterprises (SMEs), China has attempted to establish as many as third party's collateral institutions. The paper aims to study the design of collateral arrangements including collateral fee rates, risk sharing, collateral capital requirements, types of collateral institutions and recollateral institution, etc.

Design/methodology/approach

The paper extends the model of Holmstrom and Tirole to develop the analytic framework of the theory of financing collateral. From the perspective of contract design, the paper establishes a moral hazard model focusing on the minimum capital requirement of the borrower under the condition of risk neutral and limited liability, while considering the structure of lender-collateral institution-borrower.

Findings

According to the research, only under certain conditions can third party's collateral arrangements tackle the financing problems of SMEs. Diversification, anti-collateral and linked-transactions are three means to improve financing conditions, but the most important way is efficient monitoring by collateral institutions, especially when it has relative advantage over the lender. In order to improve financing conditions of SMEs, China should rely more on efficient monitoring by banks not on excess development of collateral institutions, meanwhile relax rigid collateral supervision policies. Collateral institutions should be industry-specific, association or transaction-related type.

Originality/value

First, from the perspective of contract design, the paper analyzes the comprehensive institutional arrangements of third party's collateral considering mutual relationships of component elements and develops the analytic framework of the theory of third party's collateral, especially points out necessary conditions of its efficient arrangements. Second, the paper studies various efficient financing mechanisms under the institutional arrangements of third party's collateral and focusing on the role of monitoring and monitors, and the paper also has important policy implications, i.e. the paper should develop specific collateral institutions and promote monitoring role of credit institutions.

Details

China Finance Review International, vol. 3 no. 4
Type: Research Article
ISSN: 2044-1398

Keywords

Article
Publication date: 23 September 2019

Agam Gugaliya and V.N.A. Naikan

When induction motors are considered, there is no specific cost model for net savings per year due to condition-based maintenance (CBM) covering various parameters such as…

Abstract

Purpose

When induction motors are considered, there is no specific cost model for net savings per year due to condition-based maintenance (CBM) covering various parameters such as downtime, energy, quality, etc. The purpose of this paper is to develop a cost model for the financial viability of the implementation of CBM for induction motors.

Design/methodology/approach

A literature review has been carried out to identify the existing failure modes of motor, available condition monitoring techniques, the usefulness of CBM and different maintenance models available. Then, a cost model considering all parameters has been proposed.

Findings

A cost model has been proposed for the maintenance of induction motors. Method for the economic evaluation of the model has also been suggested in the paper. The application of the model has been illustrated through a case study of a steel plant, which suggests that investment in the condition monitoring of induction motors increases the net profit of the organization.

Research limitations/implications

The proposed model is specifically designed for induction motors. All the motors under consideration are assumed to be of the same specifications, and fault in any motor is supposed to have the same effect on quality, cost, criticality, etc., of the operation and end product.

Practical implications

This paper will help the maintenance manager in decision making when maintenance action has to be carried out for a given motor under CBM for the better utilization of the equipment and resources. This paper also shows how to compute ROI on CBM investment.

Originality/value

The paper provides a cost model for the economic evaluation of implementing CBM for induction motors which will be useful to researchers and maintenance managers in effective decision making and maintenance planning. The methodology and the cost models are the original contribution of the authors.

Details

Journal of Quality in Maintenance Engineering, vol. 26 no. 2
Type: Research Article
ISSN: 1355-2511

Keywords

Article
Publication date: 13 May 2019

David Eddy-Spicer, Melanie Ehren and Mukdarut Bangpan

The collection and dissemination of standardized performance information about students, teachers, schools and school systems offer potentially important tools for school…

Abstract

Purpose

The collection and dissemination of standardized performance information about students, teachers, schools and school systems offer potentially important tools for school accountability and resource allocation as well as school improvement in developing countries. However, performance monitoring systems in developing countries are in many cases copied from those in high-income countries without a clear understanding of their functioning in contexts of limited resources and capacity for change. The purpose of this paper is to examine the conditions under which and the mechanisms through which system-wide performance monitoring affects school-level organization and processes in low- and middle-income countries (LMICs).

Design/methodology/approach

The review employs realist synthesis because of the complexity and dynamism of conditions in LMICs, the wide variability in available literature and the aim of explaining how particular organizational outcomes arise, given particular conditions. The authors draw on findings from a systematic review of 22 studies and reports, published since 2001, related to the implementation of performance monitoring.

Findings

The findings highlight key barriers to the use of data to inform school accountability and improvement. Capacity to collect, interpret and use data is an important condition to both effective external accountability as well as improvement of schools.

Originality/value

The review uses realist approaches to building middle-level theories to help scholars, educational advisers, policy makers and educational leaders understand the causal processes that result in certain outcomes from monitoring activities and to identify the conditions that are necessary for those processes to have the desired outcomes.

Details

Journal of Professional Capital and Community, vol. 4 no. 3
Type: Research Article
ISSN: 2056-9548

Keywords

Article
Publication date: 1 March 2002

Haritha Saranga

The great need for an optimum preventive maintenance strategy coupled with the fast‐developing condition‐monitoring techniques has given rise to the invention of relevant…

1360

Abstract

The great need for an optimum preventive maintenance strategy coupled with the fast‐developing condition‐monitoring techniques has given rise to the invention of relevant condition predictor (RCP)‐based maintenance approach. The main purpose of this approach is to prevent the failures due to gradual deterioration of mechanical items in order to improve system reliability and availability. This is done by monitoring relevant condition predictors of constituent maintenance significant items of the system, taking into account the availability and cost‐effectiveness of the monitoring techniques. A comprehensive review of all constituent items is carried out and a systematic approach is used to decide an optimum maintenance policy for each corresponding group of items. An optimum time to the examination of relevant condition predictors is derived mathematically with required reliability as the optimisation criterion in order to implement the RCP‐based maintenance activities.

Details

Journal of Quality in Maintenance Engineering, vol. 8 no. 1
Type: Research Article
ISSN: 1355-2511

Keywords

Article
Publication date: 19 October 2018

Sofie Pelsmakers, Evy Vereecken, Miimu Airaksinen and Cliff C.A. Elwell

Millions of properties have suspended timber ground floors globally, with around ten million in the UK alone. However, it is unknown what the floor void conditions are, nor the…

Abstract

Purpose

Millions of properties have suspended timber ground floors globally, with around ten million in the UK alone. However, it is unknown what the floor void conditions are, nor the effect of insulating such floors. Upgrading floors changes the void conditions, which might increase or decrease moisture build-up and mould and fungal growth. The purpose of this paper is to provide a review of the current global evidence and present the results of in situ monitoring of 15 UK floor voids.

Design/methodology/approach

An extensive literature review on the moisture behaviour in both uninsulated and insulated suspended timber crawl spaces is supplemented with primary data of a monitoring campaign during different periods between 2012 and 2015. Air temperature and relative humidity sensors were placed in different floor void locations. Where possible, crawl spaces were visually inspected.

Findings

Comparison of void conditions to mould growth thresholds highlights that a large number of monitored floor voids might exceed the critical ranges for mould growth, leading to potential occupant health impacts if mould spores transfer into living spaces above. A direct comparison could not be made between insulated and uninsulated floors in the sample due to non-random sampling and because the insulated floors included historically damp floors. The study also highlighted that long-term monitoring over all seasons and high-resolution monitoring and inspection are required; conditions in one location are not representative of conditions in other locations.

Originality/value

This study presents the largest UK sample of monitored floors, evaluated using a review of current evidence and comparison with literature thresholds.

Details

International Journal of Building Pathology and Adaptation, vol. 37 no. 4
Type: Research Article
ISSN: 2398-4708

Keywords

Article
Publication date: 1 December 2001

Michael W. Lewis and Luiz Steinberg

Maintenance represents a significant proportion of the overall operating costs in the mining industry. Despite the large cost of maintenance, management has only given passing…

2304

Abstract

Maintenance represents a significant proportion of the overall operating costs in the mining industry. Despite the large cost of maintenance, management has only given passing attention to the optimization of the maintenance process. The focus has remained on the optimization of mine planning and operations where all the low hanging fruit was picked years ago. Recent initiatives in the field of mobile equipment maintenance have been in the area of remote condition monitoring. In order for an advanced maintenance technology to succeed it must have a strong philosophical basis and the supporting hardware and software infrastructure. A high bandwidth radio network, reliable interfaces, and a real‐time maintenance management system will enable remote condition monitoring systems. Explores reliability centered maintenance, remote condition monitoring, and the use of production and maintenance data for real‐time interactive maintenance management.

Details

Journal of Quality in Maintenance Engineering, vol. 7 no. 4
Type: Research Article
ISSN: 1355-2511

Keywords

Open Access
Article
Publication date: 2 May 2023

Miroslav Šplíchal, Miroslav Červenka and Jaroslav Juracka

This study aims to focus on verifying the possibility of monitoring the condition of a turboprop engine using data recorded by on-board avionics Garmin G1000. This approach has…

Abstract

Purpose

This study aims to focus on verifying the possibility of monitoring the condition of a turboprop engine using data recorded by on-board avionics Garmin G1000. This approach has potential benefits for operators without the need to invest in specialised equipment. The main focus was on the inter-turbine temperature (ITT). An unexpected increase in temperature above the usual value may indicate an issue with the engine. The problem lies in the detection of small deviations when the absolute value of the ITT is affected by several external variables.

Design/methodology/approach

The ITT is monitored by engine sensors and stored by avionics 1× per second onto an SD card. This process generates large amount of data that needs to be processed. Therefore, an algorithm was created to detect the steady states of the engine parameters. The ITT value also depends on the flight parameters and surrounding environment. As a solution to these effects, the division of data into clusters that represent the usual flight profiles was tested. This ensures a comparison at comparable ambient pressures. The dominant environmental influence then remain at the ambient air temperature (OAT). Three OAT compensation methods were tested in this study. Compensation for the standard atmosphere, compensation for the standard temperature of the given flight level and compensation for the speed of the generator, where the regression analysis proved the dependence between the ambient temperature and the speed of the generator.

Findings

The influence of ambient temperature on the corrected ITT values is noticeable. The best method for correcting the OAT appears to be the use of compensation through the revolutions of the compressor turbine NG. The speed of the generator depends on several parameters, and can refine the corrected ITT value. During the long-term follow-up, the ITT differences (delta values) were within the expected range. The tested data did not include the behaviour of the engine with a malfunction or other damage that would clearly verify this approach. Therefore, the engine monitoring will continue.

Practical implications

This study presents a possible approach to turbine engine condition monitoring using limited on board avionic data. These findings can support the development of an engine condition monitoring system with automatic abnormality detection and low operating costs.

Originality/value

This article represent a practical description of problems in monitoring the condition of a turboprop engine in an aircraft with variable flight profiles. The authors are not aware of a similar method that uses monitoring of engine parameters at defined flight levels. Described findings should limit the influence of ambient air pressure on engine parameters.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 9
Type: Research Article
ISSN: 1748-8842

Keywords

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