• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.466-472
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• 1996

The nonlinear analysis was perforned for a 2-bay 2-story moment-resisting reinforced concrete plane frame with seismic detail using KDARC 2D program. The analytical models consist of the material model, the member model, the hysteretic model, and the damage model etc. The conclusion based on the results of analysis is as following. : (1) Story shear-displacement relationship is similar to the experiment result but from the energy point of view, the analysis relationship is similar to the experiment result but from the energy point of view, the analysis result was different from the experiment result. (2) Plastic hinges were found to occur mainly in beams at first story while all the columns had plastic hinges throughout the structure. (3) Failure mode is a little different from experiment result in the yielding mechanism. (4) Damage index isabout 0.25. This means that the degree of damage is moderate and can be repairable.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.33 no.2
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• pp.170-175
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• 2010

Maintaining a complex repairable system can be achieved by repairing, replacing, or any other activities. This paper proposes a joint optimization policy that is composed with ordering and replacing under minimal repair for the complex system. For this purpose, we derive the expected cost due to the minimal repair, ordering, downtime, inventory costs, and salvage value of units that follow generally distribution. Some properties about the optimum ordering policy that are suggested for our purpose shows that the optimum ordering policy minimizing the expected cost is either one of the two typical policies : (1) the original unit is replaced as soon as the ordered spare is delivered, or (2) the delivered spare is used as inventory part until the original unit fails.

• International Journal of CAD/CAM
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• v.2 no.1
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• pp.29-37
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• 2002

De-manufacturing is an entire process of collecting, disassembling, reusing, refurbishing, recycling, and/or disposing products that are obsolete or un-repairable. Designing the products for inexpensive and efficient disassembly enhances the ease of de-manufacturing. Virtual disassembly addresses the difficulty and the methods to disassemble a product in design stage rather than really disassemble a product at the end of its life cycle. Based on the virtual disassembly analysis results, design will be improved for better assembling/disassembling. This paper presents a systematic virtual disassembly methodology such as disassembly relation modeling, path/sequence automatic generation and evaluation. This paper also presents a new virtual disassembly interface paradigm via virtual reality technology for disassembly simulation in virtual environment.

• International Journal of Reliability and Applications
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• v.11 no.1
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• pp.41-53
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• 2010

In the present paper we develop a mathematical model that facilitates the calculation of reliability of a complex repairable system having three units namely super priority, priority and ordinary. The system is analyzed with the application of Gumbel Hougaard copula when different types of repair possible at a particular state due to deliberate failure. Various reliability measures such as reliability, MTTF and profit function have been evaluated by using supplementary variable and Laplace transform techniques.

• Journal of Applied Reliability
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• v.12 no.4
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• pp.255-263
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• 2012

This paper considers the cost analysis from the manufacturer's point of view for renewing replacement and non-renewing repair warranty(RRNRW) of a repairable system. To do so, we consider the renewing replacement and non-renewing repair warranty, which is proposed by Jung(2011). To analysis the expected warranty cost from the manufacturer's perspective for renewing replacement and non-renewing warranty, we obtain the expected total warranty cost and the expected warranty length which are very important information for the manufacturer. Finally, the numerical examples are presented for illustrative purpose.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.43
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• pp.357-364
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• 1997

After the buyer purchases the product, the seller's role does not end. If the product fails to function properly before the end of the warranty period, the seller is responsible for its repair or replacement under the seller's warranty policy. There are two common types of warranty policies: the free replacement warranty and the rebate warranty. Under the free replacement warranty policy, replacement or repairs during the warranty period are provided by the seller free of charge to the buyer. Under the rebate warranty policy, a failed item is replaced by a new one or is repaired at a cost to the age of the failed item. The rebate warranty is most often used for items such as a battery or an automobile tire which wear out and must be replaced at failure. This paper proposes a easy way of estimating the warranty cost under the free replacement warranty policy assuming an exponential product failure function on repairable products.

• Journal of Korea Society of Industrial Information Systems
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• v.7 no.1
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• pp.66-74
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• 2002

Warranty cost analysis for one-dimensional warranties assumes that the usage intensity (or rate) is the same for all buyers. In real life the usage intensity varies across the population of buyers. Also for products sold with warranty, preventive maintenance actions by manufacturers and buyers have a significant impact on the total costs for both parties. In this paper we deals with models to study the expected warranty cost for products with free repairable warranty with varying usage intensity and three types of preventive maintenance. We also review the literature which links warranty and maintenance and develops a framework to define new topics for research in the future and examines a new model formulation. It then develops a new model and carries out its analysis.

• Journal of the military operations research society of Korea
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• v.23 no.1
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• pp.76-87
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• 1997

This paper deals with reliability and MTTF analysis of a non-repairable man-machine system operating under different weather conditions. The system consists of a hardware(machine) and a two-operator standby subsystem such as the air combat maneuvering of fighters with dual seat. The failure times for the subsystems follow the exponential distribution with constant parameter. By considering not only the effect on hardware component but also the weather conditions and human performance factors such as the operator's errors, a Markov model is presented as a method for evaluating the system reliability of time continuous operation tasks. Laplace transforms of the various state probabilities have been derived and then reliability of the system, at any time t, has been computed by inversion process. MTTF has also been computed.

• International Journal of Reliability and Applications
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• v.4 no.1
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• pp.27-40
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• 2003

Maintenance models involving minimal imperfect repair frequently appear in the literature of reliability and operations research. Most of the literatures concerning the stochastic behavior of repairable systems assume that it takes negligible time to repair a failed system and so the length of repair time does not affect the maintenance strategy. It is more realistic to consider the length of repair times in developing maintenance model, however. In this paper, we consider an imperfect repair model with random repair time and investigate some stochastic properties of the number of perfect repairs and the number of minimal repairs. Also we derive the expressions for evaluating the expected numbers of perfect and minimal repairs in general and apply these formulas for certain parametric life distributions.

• International Journal of Reliability and Applications
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• v.16 no.1
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• pp.1-13
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• 2015

In this paper, we investigate reliability and availability of repairable systems with two types of failure. The first one is to one unit and the second one is to M units in parallel structure. Let failure rate and repair rate of [type1, type2] components are assumed to be exponentially distributed. The expressions of availability and reliability characteristics such as the system reliability and the mean time to failure are derived for two systems. We used several cases to analyze graphically the effect of various system parameters on the reliability system and availability system.