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Inventory problems are studied for a long time and many authors have investigated models with shortage phenomenon. To reduce inventory holding cost or decaying items we can have a shortage period in witch a part of demand is backordered; Although we pay fines to pending costumers, as shortage period is extended a larger portion of them will refuse to wait until replenishment. So, calculating an optimal duration for on hand inventory and shortage period with respect to inventory costs has became an interesting research field. However, related studies are rarely appeared in supply chain researches, where an integrated inventory model for a supplier and a retailer is proposed; especially when a... 

Infrastructure systems play a critical role in the economic and social activities of a community. Effective and continuous performance of these infrastructure systems is essential to the welfare and prosperity of the communities. Infrastructure systems comprise networks of interdependent assets that are built through a long and costly process. These assets are subject to a variety of factors that reduce the performance and reliability over time. These factors also increase the vulnerability of infrastructure assets in face of future probable hazards. In order to ensure the continuous and uninterrupted performance of infrastructure assets in post-hazard situations, asset managers should plan... 

This thesis targets the multidisciplinary area of time-variant seismic risk analysis of transportation networks. For this purpose, a new methodology and a library of probabilistic models are developed. Risk, in this context, denotes the probability of exceeding the sum of direct and indirect losses due to seismic events. Direct economic losses are due to the repair cost of the physical damage in the components of the network, such as bridges. The indirect losses are due to the reduced capacity of the components for traffic flow, which results in increased travel times in the network. This leads to socioeconomic losses. In this research, a reliability-based approach is adopted to carry out... 

Distribution is a necessary part of a supply chain. Location-routing problem is a problem that decide about location of facility , allocation and routing for vehicle. This research focus on modeling for multi-level and multi-product for perishable foods that include five suppliers, three plants, two depots and ten costumers. costumers and products classify according to their importance for the company and their quality into three batch. In order to decreasing of cost return orders and damaged products, a special system are Designed that products can be sent again. In real world we do not have any certain data for model’ parameters, then we consider uncertainty and use robust for showing... 

Nowadays, increasing of difficulties in production and procurement conditions such as competitiveness among manufacturing firms, variety of products, rapidly changing of customer tastes, shortening of product lifetime and complexity of demand forecasting on one hand, and key role of consumers and deteriorating products on countries revenue on the other hand, make replenishment policies of deteriorating products challenging and also interesting for both researchers and corporate managers.In this dissertation several novel models on replenishment policies for deteriorating products are proposed under uncertainty by the help of single or multi objective mathematical models. One important... 

Asset management involves making decisions related to selecting the most cost-effective asset improvement strategies. There is an increasing interest of risk-based approaches in the field of asset management. During the asset life various risk factors might influence the asset performance and the maintenance cost, therefore, it is important to incorporate these risk factors, which affect the necessity and timing of various activities. This study develops a systemic risk-based asset management methodology (framework) to manage the maintenance of infrastructure assets. This paper presents an overview of uncertainty problems in cost estimating of bridge in the future and also discusses... 

In this paper, we consider a three-echelon supply chain consisting of a producer, a distributor and a retailer. Generally each echelon tends to minimize his own inventory costs. On the other hand, competitive environment of business market, force companies to develop strategic alliances. In order to boost their partnership, separated echelons must integrate their policies, so that the total cost of the system be minimized. The model, extends the research of Wang et al.(2011) by changing the No shortage assumption into backlog shortage model.
This study assumes different deterioration rates among different echelons, and deterioration rates are time-sensitive, which is very helpful in...