Operations Research, Systems Engineering and Industrial Engineering Commons^™

Conditional Survival Analysis For Concrete Bridge Decks, Azam Nabizadeh, Habib Tabatabai, Mohammad A. Tabatabai

Civil and Environmental Engineering Faculty Articles

Bridge decks are a significant factor in the deterioration of bridges, and substantially affect long-term bridge maintenance decisions. In this study, conditional survival (reliability) analysis techniques are applied to bridge decks to evaluate the age at the end of service life using the National Bridge Inventory records. As bridge decks age, the probability of survival and the expected service life would change. The additional knowledge gained from the fact that a bridge deck has already survived a specific number of years alters (increases) the original probability of survival at subsequent years based on the conditional probability theory. The conditional expected …

Data-Driven Predictive Maintenance Scheduling Policies For Railways, Pedro Cesar Lopes Gerum, Ayca Altay, Melike Baykal-Gürsoy

Supply Chain Management

Inspection and maintenance activities are essential to preserving safety and cost-effectiveness in railways. However, the stochastic nature of railway defect occurrence is usually ignored in literature; instead, defect stochasticity is considered independently of maintenance scheduling. This study presents a new approach to predict rail and geometry defects that relies on easy-to-obtain data and integrates prediction with inspection and maintenance scheduling activities. In the proposed approach, a novel use of risk-averse and hybrid prediction methodology controls the underestimation of defects. Then, a discounted Markov decision process model utilizes these predictions to determine optimal inspection and maintenance scheduling policies. Furthermore, in the …

Bmap/G/C Queueing Model With Group Clearance Useful In Telecommunications Systems – A Simulation Approach, Srinivas Chakravarthy, Alexander Rumyantsev

Industrial & Manufacturing Engineering Publications

Queueing models in which customers or messages arrive in batches with inter-arrival times of batches possibly correlated and services rendered in batches of varying sizes play an important role in telecommunication systems. Recently queueing models of BMAP/G/1-type in which a new type of group clearance was studied using embedded Markov renewal process as well as continuous time Markov chain whose generator has a very special structure. In this paper, we generalize these models to multi-server systems through simulation approach. After validating the simulation model for the single server case, we report our simulated results for much more general situations.

Impacts Of Freight Consolidation And Truck Sharing On Freight Mobility, Tieming Liu, Chaoyue Zhao

Data

Corresponding data set for Tran-SET Project No. 17ITSOKS02. Abstract of the final report is stated below for reference:

"The trucking industry is an important sector of the U.S. economy. However, it is quite fragmented, hindering the efficiency of cargo transportation and the ability for small carriers to identify demands to fill full truck loads. The focus of this research is to study models and algorithms in order to aid online freight marketplaces to identify efficient consolidation strategies. To accomplish this aim, a new mixed integer programming model for the pickup and delivery problem has been developed. The model is geared …

Impacts Of Freight Consolidation And Truck Sharing On Freight Mobility, Tieming Liu, Chaoyue Zhao

Publications

The trucking industry is an important sector of the U.S. economy. However, it is quite fragmented, hindering the efficiency of cargo transportation and the ability for small carriers to identify demands to fill full truck loads. The focus of this research is to study models and algorithms in order to aid online freight marketplaces to identify efficient consolidation strategies. To accomplish this aim, a new mixed integer programming model for the pickup and delivery problem has been developed. The model is geared towards identifying effective freight consolidation opportunities. A branch-and-cut algorithm to solve the model was also developed. The model …

36% Reduction In Fuel Resupply Using A Hybrid Generator & Battery System For An Austere Location, David J. Chester [*], Torrey J. Wagner, Douglas S. Dudis

Faculty Publications

The DOD energy policy is to increase energy security resiliency, and mitigate costs in the use and management of energy^[1] Forward operating bases (FOBs) are remote, austere base camps that support an operationally defined mission with a limited or no ability to draw from an energy grid and have historically relied on diesel-powered generators for the primary production of energy.^[2] Generators are sized to meet a theoretical peak demand, but steady state loads are far below this peak, resulting in under-loaded generators.^[3] Under-loaded diesel generators decrease efficiency and increase the need for maintenance, affecting the lifespan of …

Biologically Inspired Design Of Context-Aware Smart Products, Ang Liu, Ivan Teo, Diandi Chen, Stephen Lu, Thorsten Wuest, Zhinan Zhang, Fei Tao

Faculty & Staff Scholarship

The rapid development of information and communication technologies (ICTs) and cyber–physical sys-tems (CPSs) has paved the way for the increasing popularity of smart products. Context-awareness isan important facet of product smartness. Unlike artifacts, various bio-systems are naturally characterizedby their extraordinary context-awareness. Biologically inspired design (BID) is one of the most commonlyemployed design strategies. However, few studies have examined the BID of context-aware smart prod-ucts to date. This paper presents a structured design framework to support the BID of context-awaresmart products. The meaning of context-awareness is defined from the perspective of product design.The framework is developed based on the theoretical foundations …

A Case For Open Mission Systems In Dod Aircraft Avionics, Michael J. Brown, R. David Fass, Jonathan D. Ritschel

Faculty Publications

The DOD is adopting open mission systems (OMS) as the future in the military aviation environment. OMS proponents promise reduced costs and truncated schedules through increased competition in the marketplace and reduced coding efforts. To the best of our knowledge, no studies have examined the success of these open architectures in the DOD. Therefore, we investigate costs and schedule for a recent DOD avionics OMS demonstration platform in comparison to 13 historically analogous programs.