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Zhisheng Ye - One of the best experts on this subject based on the ideXlab platform.

  • aggregate discounted Warranty Cost forecasting considering the failed but not reported events
    Reliability Engineering & System Safety, 2017
    Co-Authors: Xin Wang, Zhisheng Ye, Loon Ching Tang
    Abstract:

    Warranty claims usually incur substantial Costs to the manufacturers. In practice, it is not accurate or economical to reserve money for future claims based on the prediction of the overall (life cycle) Warranty Cost. As a more appropriate alternative, the aggregate Warranty Cost forecast technique can reduce the liquidity risks and improve the Warranty service efficiency. In addition, when a product fails during the Warranty period, a Warranty claim will be counted only when the customer reports the failure to the manufacturer. This paper focuses on forecasting the discounted Warranty Cost, which depends on the product sales and failure processes, Warranty terms, and customer behaviors, over arbitrary time interval. To characterize the failed-but-not-reported phenomenon, a flexible time-dependent function is proposed. We derive the mathematical formulations of related factors to discuss the modeling process of total discounted Warranty Cost over an arbitrary time interval (TDWCATI). The impacts of Warranty length and customer reporting behavior are explored. The expectation and variance of the TDWCATI are obtained under the pro-rata Warranty policy and the nonrenewable minimal-repair policy, which shows that the TDWCATI is useful in planning future Warranty services and budgets over a specific time period.

  • aggregate discounted Warranty Cost forecast for a new product considering stochastic sales
    IEEE Transactions on Reliability, 2016
    Co-Authors: Wei Xie, Zhisheng Ye
    Abstract:

    Most commercial products are sold with a Warranty. Product repairs during the Warranty period are often free of charge, and contribute significantly to the Costs of a manufacturer. Estimation of the Warranty Costs is important for the manufacturer to prepare sufficient Warranty reserves for future claims. Because products are often sold to customers intermittently, the total number of sold units under Warranty varies over time, which presents difficulties in forecasting the Warranty Costs over time. In this study, we consider the stochastic sales process, and derive the expectation and variance of the aggregate discounted Warranty Costs within a given period of time. By taking the variation of the Warranty Costs into consideration, the result can be used in the preparation of a conservative Warranty reserve for a new product. The discounted life-cycle Warranty Cost is a special case of our model, and it can also be determined from our result. Numerical results show the applicability of our model in estimating periodic discounted Warranty Costs, and preparing both short-term and long-term Warranty reserves.

Stefanka Chukova - One of the best experts on this subject based on the ideXlab platform.

  • Warranty Cost analysis with an alternating geometric process
    Proceedings of the Institution of Mechanical Engineers Part O: Journal of Risk and Reliability, 2019
    Co-Authors: Richard Arnold, Stefanka Chukova, Yu Hayakawa, Sarah Marshall
    Abstract:

    In this study, we model the Warranty claims process and evaluate the Warranty servicing Costs under non-renewing, renewing and restricted renewing free repair warranties. We assume that the repair ...

  • Warranty Cost analysis increasing Warranty repair times
    Applied Stochastic Models in Business and Industry, 2018
    Co-Authors: Sarah Marshall, Stefanka Chukova, Richard Arnold, Yu Hayakawa
    Abstract:

    In this study, we model the Warranty servicing Costs under nonrenewing and renewing free repair warranties. We assume nonzero increasing repair times with the Warranty Cost depending on the length of the repair time. An increasing geometric process is used to model the consecutive repair times. We introduce the generalised alternating renewal process, which is an alternating process with cycles consisting of an item's operational time followed by the corresponding repair time. We derive analytical results for a generalised alternating renewal process with a finite time horizon and use them to evaluate the Warranty Costs over the Warranty period and over the life cycle of the product under the nonrenewing free repair Warranty and renewing free repair Warranty. Properties of the model are demonstrated through a simulation study and through the application to Warranty claims data from an automotive manufacturer.

  • Warranty Cost analysis with an alternating geometric process
    International Conference on Quality Reliability Risk Maintenance and Safety Engineering, 2018
    Co-Authors: Richard Arnold, Stefanka Chukova, Yu Hayakawa, Sarah Marshall
    Abstract:

    In this study we model the Warranty claims process and evaluate the Warranty servicing Costs under non-renewing and renewing free repair warranties. We assume that the repair time for rectifying the claims is non-zero and the repair Cost is a function of the length of the repair time. To accommodate the ageing of the product and repair equipment, we use a decreasing geometric process to model the consecutive operational times and an increasing geometric process to model the consecutive repair times. We identify and study the alternating geometric process (AGP), which is an alternating process with cycles consisting of the item's operational time followed by the corresponding repair time. We derive new results for the AGP in finite horizon and use them to evaluate the Warranty Costs over the Warranty period and over the life cycle of the product under a non-renewing free repair Warranty (NRFRW), a renewing free repair Warranty (RFRW) and a restricted renewing free repair Warranty (RRFRW(n)). Properties of the model are demonstrated using a simulation study.

  • one dimensional Warranty Cost analysis for second hand items an overview
    International Journal of Quality & Reliability Management, 2013
    Co-Authors: Stefanka Chukova, Mahmood Shafiee
    Abstract:

    Purpose – The purpose of this paper is to review and develop stochastic models for the evaluation of the expected Warranty Cost, from dealer's viewpoint, for second hand items sold under different Warranty policies.Design/methodology/approach – This study makes a useful contribution to the Warranty literature by developing a framework to study one dimensional Warranty policies for second‐hand products from dealer's viewpoint. Also, numerical examples are provided to illustrate the application of these models.Findings – Despite the fact that warranties for second‐hand products are commonly used, the accurate pricing of warranties in many situations remains an unsolved problem, for both the dealer and customer. The proposed framework allows the dealer to analyze the Cost of alternative Warranty policies before deciding on the policy to be offered with the sale of a second‐hand item.Originality/value – The policies and models developed in this paper can be useful in managerial decisions making related to sec...

  • One‐dimensional Warranty Cost analysis for second‐hand items: an overview
    International Journal of Quality & Reliability Management, 2013
    Co-Authors: Stefanka Chukova, Mahmood Shafiee
    Abstract:

    Purpose – The purpose of this paper is to review and develop stochastic models for the evaluation of the expected Warranty Cost, from dealer's viewpoint, for second hand items sold under different Warranty policies.Design/methodology/approach – This study makes a useful contribution to the Warranty literature by developing a framework to study one dimensional Warranty policies for second‐hand products from dealer's viewpoint. Also, numerical examples are provided to illustrate the application of these models.Findings – Despite the fact that warranties for second‐hand products are commonly used, the accurate pricing of warranties in many situations remains an unsolved problem, for both the dealer and customer. The proposed framework allows the dealer to analyze the Cost of alternative Warranty policies before deciding on the policy to be offered with the sale of a second‐hand item.Originality/value – The policies and models developed in this paper can be useful in managerial decisions making related to sec...

Loon Ching Tang - One of the best experts on this subject based on the ideXlab platform.

  • aggregate discounted Warranty Cost forecasting considering the failed but not reported events
    Reliability Engineering & System Safety, 2017
    Co-Authors: Xin Wang, Zhisheng Ye, Loon Ching Tang
    Abstract:

    Warranty claims usually incur substantial Costs to the manufacturers. In practice, it is not accurate or economical to reserve money for future claims based on the prediction of the overall (life cycle) Warranty Cost. As a more appropriate alternative, the aggregate Warranty Cost forecast technique can reduce the liquidity risks and improve the Warranty service efficiency. In addition, when a product fails during the Warranty period, a Warranty claim will be counted only when the customer reports the failure to the manufacturer. This paper focuses on forecasting the discounted Warranty Cost, which depends on the product sales and failure processes, Warranty terms, and customer behaviors, over arbitrary time interval. To characterize the failed-but-not-reported phenomenon, a flexible time-dependent function is proposed. We derive the mathematical formulations of related factors to discuss the modeling process of total discounted Warranty Cost over an arbitrary time interval (TDWCATI). The impacts of Warranty length and customer reporting behavior are explored. The expectation and variance of the TDWCATI are obtained under the pro-rata Warranty policy and the nonrenewable minimal-repair policy, which shows that the TDWCATI is useful in planning future Warranty services and budgets over a specific time period.

Yu Hayakawa - One of the best experts on this subject based on the ideXlab platform.

  • Warranty Cost analysis with an alternating geometric process
    Proceedings of the Institution of Mechanical Engineers Part O: Journal of Risk and Reliability, 2019
    Co-Authors: Richard Arnold, Stefanka Chukova, Yu Hayakawa, Sarah Marshall
    Abstract:

    In this study, we model the Warranty claims process and evaluate the Warranty servicing Costs under non-renewing, renewing and restricted renewing free repair warranties. We assume that the repair ...

  • Warranty Cost analysis increasing Warranty repair times
    Applied Stochastic Models in Business and Industry, 2018
    Co-Authors: Sarah Marshall, Stefanka Chukova, Richard Arnold, Yu Hayakawa
    Abstract:

    In this study, we model the Warranty servicing Costs under nonrenewing and renewing free repair warranties. We assume nonzero increasing repair times with the Warranty Cost depending on the length of the repair time. An increasing geometric process is used to model the consecutive repair times. We introduce the generalised alternating renewal process, which is an alternating process with cycles consisting of an item's operational time followed by the corresponding repair time. We derive analytical results for a generalised alternating renewal process with a finite time horizon and use them to evaluate the Warranty Costs over the Warranty period and over the life cycle of the product under the nonrenewing free repair Warranty and renewing free repair Warranty. Properties of the model are demonstrated through a simulation study and through the application to Warranty claims data from an automotive manufacturer.

  • Warranty Cost analysis with an alternating geometric process
    International Conference on Quality Reliability Risk Maintenance and Safety Engineering, 2018
    Co-Authors: Richard Arnold, Stefanka Chukova, Yu Hayakawa, Sarah Marshall
    Abstract:

    In this study we model the Warranty claims process and evaluate the Warranty servicing Costs under non-renewing and renewing free repair warranties. We assume that the repair time for rectifying the claims is non-zero and the repair Cost is a function of the length of the repair time. To accommodate the ageing of the product and repair equipment, we use a decreasing geometric process to model the consecutive operational times and an increasing geometric process to model the consecutive repair times. We identify and study the alternating geometric process (AGP), which is an alternating process with cycles consisting of the item's operational time followed by the corresponding repair time. We derive new results for the AGP in finite horizon and use them to evaluate the Warranty Costs over the Warranty period and over the life cycle of the product under a non-renewing free repair Warranty (NRFRW), a renewing free repair Warranty (RFRW) and a restricted renewing free repair Warranty (RRFRW(n)). Properties of the model are demonstrated using a simulation study.

  • Warranty Cost analysis quasi renewal inter repair times
    International Journal of Quality & Reliability Management, 2005
    Co-Authors: Stefanka Chukova, Yu Hayakawa
    Abstract:

    Purpose – To provide a brief introduction to Warranty analysis and a classification of general repairs. To introduce the notion of accelerated probability distribution and use it to model imperfect Warranty repairs.Design/methodology/approach – The notion of accelerated probability distribution is discussed and its similarity with quasi‐renewal and geometric processes is observed. An approach to modeling imperfect Warranty repairs based on the accelerated probability distributions is presented, and the corresponding expected Warranty Cost over the Warranty period under non‐renewing free replacement Warranty policy is evaluated.Findings – It is observed that quasi‐renewal and the geometric processes are equivalent. Using data from an existing Warranty database it is shown that the inter‐repair times form a quasi‐renewal process. The corresponding expected Warranty Cost over the Warranty period under a non‐renewing free replacement Warranty policy is evaluated.Research limitations/implications – This approa...

  • Warranty Cost analysis: quasi‐renewal inter‐repair times
    International Journal of Quality & Reliability Management, 2005
    Co-Authors: Stefanka Chukova, Yu Hayakawa
    Abstract:

    Purpose – To provide a brief introduction to Warranty analysis and a classification of general repairs. To introduce the notion of accelerated probability distribution and use it to model imperfect Warranty repairs.Design/methodology/approach – The notion of accelerated probability distribution is discussed and its similarity with quasi‐renewal and geometric processes is observed. An approach to modeling imperfect Warranty repairs based on the accelerated probability distributions is presented, and the corresponding expected Warranty Cost over the Warranty period under non‐renewing free replacement Warranty policy is evaluated.Findings – It is observed that quasi‐renewal and the geometric processes are equivalent. Using data from an existing Warranty database it is shown that the inter‐repair times form a quasi‐renewal process. The corresponding expected Warranty Cost over the Warranty period under a non‐renewing free replacement Warranty policy is evaluated.Research limitations/implications – This approa...

D K Manna - One of the best experts on this subject based on the ideXlab platform.

  • Optimal determination of Warranty region for 2D policy: A customers' perspective
    Computers & Industrial Engineering, 2006
    Co-Authors: D K Manna, Sagnik Sinha
    Abstract:

    Warranty is treated by the manufacturer as a marketing strategy that creates better customer satisfaction, which finally helps to get hold of a bigger market share. The Cost incurred towards this service is termed as Warranty Cost, which is a function of Warranty policy and region, product quality and reliability, and the customers' usage pattern. Under the 2D Warranty policy, there exists numerous iso-Cost regions for any specified value of Warranty Cost. In this article, we propose a methodology to determine the optimal region when customers' utility is measured by the length of Warranty coverage time. It is believed that the results will help the manufacturer to provide improved customer service.

  • Warranty Cost estimation of a multi module product
    International Journal of Quality & Reliability Management, 2004
    Co-Authors: D K Manna, A Kulandaiyan
    Abstract:

    This article deals with the problem of Cost estimation for increased Warranty time of a multi‐module product. The Warranty policy of interest is two‐dimensional involving Warranty limits on both age and usage of the product. Failure of the product is caused due to malfunctioning of its module(s). Warranty service is rendered through repair or replacement of the respective module(s). From the past data, it is observed that age and usage are highly correlated. Based on life (age) data, the joint life distribution of the modules is well described by multivariate exponential distribution of Marshall and Olkin. The same is utilized to estimate Cost for desired Warranty times by the method of simulation.

  • Warranty Cost estimation of a multi‐module product
    International Journal of Quality & Reliability Management, 2004
    Co-Authors: D K Manna, A Kulandaiyan
    Abstract:

    This article deals with the problem of Cost estimation for increased Warranty time of a multi‐module product. The Warranty policy of interest is two‐dimensional involving Warranty limits on both age and usage of the product. Failure of the product is caused due to malfunctioning of its module(s). Warranty service is rendered through repair or replacement of the respective module(s). From the past data, it is observed that age and usage are highly correlated. Based on life (age) data, the joint life distribution of the modules is well described by multivariate exponential distribution of Marshall and Olkin. The same is utilized to estimate Cost for desired Warranty times by the method of simulation.

  • Cost estimation under renewing Warranty policy an application
    Quality Engineering, 2003
    Co-Authors: Sandeep Mondal, D K Manna
    Abstract:

    This article deals with life analysis and Warranty Cost estimation of temperature switch-cum-sensor (TSS). It involves analysis of one-dimensional, renewing, and free-replacement Warranty policy. Life distribution of TSS is identified from Warranty failure data. Then, Warranty Cost is estimated for an extended time period using the bootstrap method.

  • Cost Estimation Under Renewing Warranty Policy—An Application
    Quality Engineering, 2003
    Co-Authors: Sandeep Mondal, D K Manna
    Abstract:

    This article deals with life analysis and Warranty Cost estimation of temperature switch-cum-sensor (TSS). It involves analysis of one-dimensional, renewing, and free-replacement Warranty policy. Life distribution of TSS is identified from Warranty failure data. Then, Warranty Cost is estimated for an extended time period using the bootstrap method.