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The effects of cyber threats on maintenance outsourcing and age replacement policy

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Abstract

This research examines maintenance outsourcing in the presence of cyber-attacks. The research findings contribute to the literature on maintenance outsourcing by considering how cyber-attacks affect channel coordination and, specifically, cost subsidization. The Internet of Things assumes the risk that a “smart” or connected manufacturing system could become the target of a cyber-attack. Manufacturers have to face the difficult decision of adopting increasingly costly security technologies or having the manufacturing system remain vulnerable to cyber threats. This study develops a model addressing this dilemma by providing insight into the effects of cost subsidization and tools that manufacturers may use to evaluate the impact that installation of a security system has on a manufacturing system’s profit. The research also analyzes the effect of a cyber-attack on the system when using an age replacement policy. Under such a system, repairs may cost more than replacement which suggests that new components are required immediately after failure. For “smart” manufacturing systems that use either maintenance outsourcing or an age replacement policy, the study provides optimal solutions for firms to maximize the manufacturing system’s profit with consideration of the firms’ physical equipment failure and cyber-attack rates. The findings help determine the value of a security system by providing guidelines that address the effects of the cost, failure rate, and “successful” cyber-attack rate parameters.

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An external contractor receives a payment from a manufacturer for periodically performing preventive maintenance and for performing minimal repairs whenever process failures occur. Suppose a new technology will be available in the future, but the timing is uncertain. We propose specifying one or multiple time points in a maintenance contract, at which the manufacturer can adopt (switch to) the new technology, if it becomes available, and change the preventive maintenance schedule for the remaining time in the contract period. A model is developed to determine the value of using these (switch) points in a maintenance contract to the manufacturer. The numerical results show that, with a higher arrival rate of the new technology, the value becomes greater, and thus, the optimal switch point should be set earlier. Furthermore, if the new technology reduces maintenance costs, using switch points adds more value to a cost-plus-margin method than either the fixed payment or cost-plus-fixed-fee methods. On the other hand, if adopting the new technology results in higher maintenance costs, the value using switch points is higher for the fixed payment method.
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We propose a simple game for modeling containment of the spread of viruses in a graph of n nodes. Each node must choose to either install anti-virus software at some known cost C, or risk infection and a loss L if a virus that starts at a random initial point in the graph can reach it without being stopped by some intermediate node. We prove many game theoretic properties of the model, including an easily applied characterization of Nash equilibria, culminating in our showing that a centralized solution can give a much better total cost than an equilibrium solution. Though it is NP-hard to compute such a social optimum, we show that the problem can be reduced to a previously unconsidered combinatorial problem that we call the sum-of-squares partition problem. Using a greedy algorithm based on sparse cuts, we show that this problem can be approximated to within a factor of O(log1.5n).
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This paper investigates a machine repair problem with homogeneous machines and standbys available, in which multiple technicians are responsible for supervising these machines and operate a (R, V, K) synchronous vacation policy. With such a policy, if any V idle technicians exist in the system, these V (V < R) technicians would take a synchronous vacation. Upon returning from vacation, they would take another vacation if there is no broken machine waiting in the queue. This pattern continues until at least one failed machine arrives. It is assumed that the number of teams/groups on vacation is less than or equal to K (0 <= KV < R). The matrix analytical method is employed to obtain a steady-state probability and the closed-form expression of the system performance measures. Efficient approaches are performed to deal with the optimization problem of the discrete/continuous variables while maintaining the system availability at a specified acceptable level.
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This paper considers replacement and maintenance policies for an operating unit which works at random times for jobs. The unit undergoes minimal repairs at failures and is replaced at a planned time T or at a number N of working times, whichever occurs first. The expected cost rate is obtained, and an optimal policy which minimizes it is derived analytically. The imperfect preventive maintenance (PM) model, where the unit is improved by PM after the completion of each working time, is analyzed. Furthermore, when the work of a job incurs some damage to the unit, the replacement model with number N is proposed. The expected cost rate is obtained by using theory of cumulative processes. Two modified models, where the unit is replaced at number N or at the first completion of the working time over time T, and it is replaced at T or number N, whichever occurs last, are also proposed. Finally, when the unit is replaced at time T, number N or Kth failure, whichever occurs first, the expected cost rate is also obtained.
Article
A model is presented in this paper for maintenance service contract design, negotiation and optimization. The model was developed under the assumption that there are one customer and one unique service provider who is the Original Equipment Manufacturer (OEM) and is called the agent in this paper. This is typically applied to the situation where the OEM is the only possible service supplier such as in the case of major military equipment in the defense sector. Three contract options were considered, depending on the extent of outsourced maintenance activities. From an agent point of view, they are, (1), the agent carries out all repairs and inspections; (2), the agent carries out failure based repairs, and (3), the agent does inspections and repairs to the defects identified at inspections. For options two and three, the customer does the rest of maintenance. The relationship between inspections and failures was modeled using the delay time concept and a numerical example was illustrated. The cases of perfect information to both parties and information asymmetry were also discussed in the example. The model developed can be used for contract design, negotiation and optimization.
Article
The objective of this paper is to study learning effects on maintenance outsourcing. We consider a situation in which a manufacturer offers a short-term outsourcing contract to an external contractor who is responsible for scheduling and performing preventive maintenance and carrying out minimal repairs when the process fails. The manufacturer's payment to the contractor consists of a fixed amount along with cost subsidization for each maintenance operation performed. We assume learning occurs when the contractor performs preventive maintenance that reduces both time and cost. Two types of learning are considered: natural learning and learning by costly efforts. We demonstrate that a well-designed payment scheme can induce the contractor to adopt the maintenance schedule that maximizes the manufacturer's profit.
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To aid researchers in the simulation and testing of maintenance policies for complex, computer controlled technological equipment this paper presents a description of failure and repair rate characteristics as well as distribution data for a typical flexible manufacturing system (FMS) that is in use in a mid-western (USA) manufacturing plant. Separate data are included for mechanical, hydraulic, electrical, electronic, software and human failures as well as repairs. The data are also fit with appropriate theoretical distributions.
Cyberattack shows vulnerability of gas pipeline network
  • C Krauss
Krauss, C., 2018. Cyberattack shows vulnerability of gas pipeline network. New York Times. Retrieved from 〈https://www.nytimes.com/2018/04/04/business/energy-en vironment/pipeline-cyberattack.html〉.
Your guide to good-enough compliance
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Holmes, A., 2007. Your guide to good-enough compliance. Retrieved from: 〈https ://www.cio.com/article/2439324/risk-management/yourguide-to-good-enough -compliance.html?page=2〉.
Why manufacturers should be mindful of cybersecurity
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Polyakov, A., 2017. Why manufacturers should be mindful of cybersecurity. Forbes Technology Council. Retrieved from 〈https://www.forbes.com/sites/forbestechcoun cil/2017/06/01/why-manufacturers-should-be-mindful-of-cybersecurity/#65ee1 96d10d2〉.