• Journal of Applied Reliability
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• v.15 no.1
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• pp.1-5
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• 2015

This note suggests three approaches to improve reliability in developing weapon systems. The high complexity of the weapon systems make it hard to analyze and predict of those reliability. Current situations of the reliability have been reviewed in terms of logistics support analysis (LSA), warranty policy, maintenance and development. Three suggestions are notified to improve the reliability considering the complexity of the weapon systems.

• International Journal of Reliability and Applications
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• v.12 no.1
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• pp.41-48
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• 2011

This paper considers the maintenance model suggested by Jung and Park (2010) to adopt the Bayesian approach and obtain an optimal replacement policy following the expiration of NFRRW. As the criteria to determine the optimal maintenance period, we use the expected cost during the life cycle of the system. When the failure times are assumed to follow a Weibull distribution with unknown parameters, we propose an optimal maintenance policy based on the Bayesian approach. Also, we describe the revision of uncertainty about parameters in the light of data observed. Some numerical examples are presented for illustrative purpose.

• The Korean Journal of Applied Statistics
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• v.23 no.6
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• pp.1147-1156
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• 2010

This paper proposes a replacement policy following the expiration of a non-renewing free replacement-repair Warranty(NFFRW). The non-renewing free replacement-repair warranty is defined and then the maintenance model following the expiration of the NFRRW is studied from the user's point of view. As the criteria to determine the optimality of the maintenance policy, we consider the expected cost rate per unit time from the user's perspective. All maintenance costs of the system incurred after the expiration of the warranty are paid by the user. Given the cost structures during the life cycle of the system, we determine the optimal maintenance period following the expiration of a NFRRW. Finally, the numerical examples are presented for illustrative purposes.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.446-449
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• 2007

For the restoration of construction industry, the government have offered the policy since the end of 1990. It has offered to develop the world-class technology and establish the effective production structure. In the government policy, the delivery and contracting method has improved so that construction industry could be recognized. Foreign countries have conducted the R&D and application of Innovative Contracting for improvement of facilities, reduction of LCC and innovation of contractor. Among the Innovative Contracting, 'Performance Warranty Contracting' is defined that A guarantee of the integrity of a product and of the makers responsibility for the replacement or repair of deficiencies. Performance Warranty Contracting is used for technology developments of contractor, improvement of quality, reduction of LCC, prevention of early deficiencies and reduction of owner's inspection works. This paper analyzes concept and effects of Performance Warranty Contracting and presents considerations according to the introduction.

• Communications for Statistical Applications and Methods
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• v.15 no.1
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• pp.77-86
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• 2008

This paper develops the optimal periodic preventive maintenance policy following the expiration of non-renewing warranty. We assume that Wu and Clements-Croome's (2005) periodic PM model with random maintenance quality is utilized to maintain the system after the non-renewing warranty is expired. Given the cost structure to the user during the cycle of the product, we drive the expressions for the expected cost rate per unit time. Also, we obtain the optimal number and the optimal period by minimizing the expected cost rate per unit time. The numerical examples are presented for illustrative purpose.

• Journal of the Korean Data and Information Science Society
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• v.22 no.4
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• pp.775-784
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• 2011

In this paper, we consider the periodic preventive maintenance model for repairable system following the expiration of non-renewing free replacement-repair warranty (NFRRW). Under this preventive maintenance model, we derive the expressions for the expected cycle length, the expected total cost and the expected cost rate per unit time. Also, we determine the optimal preventive maintenance period and the optimal preventive maintenance number by minimizing the expected cost rate per unit time. Finally, the optimal periodic preventive maintenance policy is given for Weibull distribution case.

• Journal of the Korean Operations Research and Management Science Society
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• v.25 no.3
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• pp.41-48
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• 2000

We consider the question of warranties for repairable items. During the warranty period, each time an item fails the manufacturer has the obligation to restore the item to operational condition either by repairing the item or by replacing it by a new item. In this paper, we consider a warranty policy for making this decision based on the condition of the failed item. For products with phase-type lifetime distributions where the phases represent the condition of the item, we develop algorithms to determine the expected cost of servicing a warranty and use it in making the repair/replacement decision. illustrative numerical examples are presented.

• International Journal of Reliability and Applications
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• v.3 no.3
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• pp.113-124
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• 2002

This paper suggests the optimal periodic preventive maintenance policies after the combination warranty is expired. After the combination warranty is expired, a repairable system undergoes PM periodically and is minimally repaired at each failure. And also the system is replaced by a new system at the N th PM. In this case, we derive the mathematical formula for the expected cost rate per unit time. The optimal number and period for the periodic PM that minimize the expected cost rate per unit time are obtained. Some numerical examples are presented for illustrate purpose.

• Proceedings of the Korean Statistical Society Conference
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• 2005.11a
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• pp.73-78
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• 2005

This paper considers a preventive maintenance policy following the expiration of renewing warranty, Most preventive maintenance models assume that each PM costs a fixed predetermined amount regardless of the effectiveness of each PM. However, it seems more reasonable to assume that the PM cost depends on the degree of effectiveness of the PM activity. In this paper we consider a periodic preventive maintenance policy following the expiration of renewing warranty when the PM cost is an increasing function of the PM effect. The optimal number and period for the periodic PM policy with effect dependent cost that minimize the expected cost rate per unit time over an infinite time span are obtained.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.73
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• pp.65-90
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• 2017

The rule of warranty in English insurance law was established in the second part of the $18^{th}$ century by Lord Mansfield, who laid the foundations of the modern English law of insurance contract and developed very different rule of insurance law, especially in the field of warranty. At the time of Lord Mansfield, warranty, that is, the promise given by the assured, played an important role for the insurer to assess the scope of the risk. Legal environments, however, have changed since the age of Lord Mansfield. English and Scottish Commissions proposed very dramatic reform of law in the field of warranty law to reflect the changes of legal environment through the Insurance Act 2016. This article intends to consider the legal implications through the comparative analysis between the new regime of warranty in the Insurance Act 2015 and MIA 1906. The major changes in the Insurance Act 2015 are summarized as following. First, Basis of the contract clauses in non-consumer insurance contracts should be of no effect and representations should not be capable of being converted into warranties by means of a policy term or statement on the proposal form. This requirement should not be capable of being avoided by the use of a contract term and the arrangement of contracting out by parties should be of no effect. Secondly, The existing remedy for breach of warranty, that is, automatic discharge of the insurer's liability, should be removed. Instead, the insurer's libility should be suspended from the point of breach of warranty and reattach if and when a breach of warranty has been remedies. Thirdly, A breach of warranty should genally be regarded as remedied where the insured ceases to be in breach of it. In the other hand, for time-specific warranties which apply at or by an ascertainable time, a breach should be regarded as remedies, if the risk to which the warranty relates later, becomes essentially the same as that originally contemplated by the parties. Fourthly, where a term of an insurance contract relates to a particular kind of loss, or loss at a particular location/time, the breach of that term should only give the remedy in relation to loss of that particular kind of loss, or at a particular location/time. Finally, whether a term of an insurance contrat relates to loss of a particular kind of at a particular location/time should be determined objectively, based on whether compliance with that ther would tend to reduce the risk of the occurrence of that category of loss.