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We study a single-item, multi-period, stochastic perishable inventory problem under both backlogging and lost-sales circumstances, with and without an order capacity constraint in each period.
We first model the problem as a dynamic program and then develop two heuristics namely, Dual-Balancing (DB) and Look-Ahead (LA) policies, to approximate the optimal inventory level at the beginning of each period. To characterize the holding and backlog cost functions under the proposed polices, we introduce a truncated marginal holding cost for the marginal cost accounting scheme. Our numerical examples demonstrate that both DB and LA policies have a possible worst-case performance guarantee of two in perishable inventory systems under different assumptions, and the LA policy significantly outperforms the DB policy in most situations.
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We see faces every day within a rich situational context. Previous ERP research has demonstrated that priming faces with contextual sentences varying in self-relevance and valence alters electrocortical and emotional responding to them, though the time-course of these effects is still unclear. It is also unclear if these effects interact with another cue that inherently contains emotional and self-referential information: whether or not the face is looking at the participant. We primed direct and averted gaze neutral faces (gaze manipulation) with emotional sentences to give them context. These sentences contained positive or negative opinions (valence manipulation) that the face held of the participants or of someone else (self-relevance manipulation). After reading each sentence, participants viewed the corresponding face and rated h...
The advent of rectenna systems almost half a century ago has enabled numerous applications in a number of areas, with the main goal of recycling the ambient microwave energy. In previously presented rectennas, microstrip antennas were the main energy source used to capture and convert microwaves to AC power. However, the conversion efficiency of antennas have never been examined in terms of their capability of absorbing microwave energy, and hence any enhancements to the overall efficiency of rectenna systems were mainly attributed to the rectification circuitry instead of the antenna. In the first part of this dissertation, a novel electromagnetic energy collector is presented, consisting of an array of Split Ring Resonators (SRRs), used for the first time as the main electromagnetic source of energy in a rectenna system. The SRR arra...
As traffic on urban road network increases, congestion and delays are becoming more severe. At grade intersections form capacity bottlenecks in urban road networks because at these locations, capacity must be shared by competing traffic movements. Traffic signals are the most common method by which the right of way is dynamically allocated to conflicting movements.
A range of traffic signal control strategies exist including fixed time control, actuated control, and adaptive traffic signal control (ATSC). ATSC relies on traffic sensors to estimate inputs such as traffic demands, queue lengths, etc. and then dynamically adjusts signal timings with the objective to minimize delays and stops at the intersection.
Despite, the advantages of these ATSC systems, one of the barriers limiting greater use of these systems is the large num...
Glaucoma is a chronic disease associated with progressive dysfunction of the retinal ganglion cells (RGC), reduction of the retinal blood flow, thinning of the retinal nerve fiber layer (RNFL) and deformation of the optical nerve head (ONH). It is the second leading cause of blindness worldwide, with an estimate of 64.3 million people between the ages of 40 to 80 years affected in 2013, 76.7 million by 2020, and 111.8 million by 2040. Currently, there is no cure for glaucoma and any clinically available pharmaceutical or surgical approaches to treating the disease can only slow its progression. Therefore, early detection and treatment are essential for managing the glaucoma progression. Elevated intraocular pressure (IOP) is one of the most well studied and documented pathogenic risk factors for open-angle glaucoma (OAG), and as such, ...
With the introduction of the Millennium and Sustainable Development Goals, the level of sophistication required to measure the impact of international development has grown. However, evidence suggests that international non-governmental organizations (NGOs) have been slow to invest in development evaluation; instead of using evidence-based tools to enhance performance, such as logic models or benchmarks, NGOs engage in activities to demonstrate their good work (e.g., report writing, monitoring progress). In light of the current biophysical, socioeconomic, political, and human challenges that make the water-health nexus a “wicked problem,” this thesis addresses the knowledge gap in our understanding of factors that influence the measurable success of an NGO in water-based development. Using a case study design, evaluation frameworks wer...
The human genome project has allowed for the rapid identification of a large number of protein families based on similarities in their genetic sequences. The acyl-glycerol phosphate acyltransferase (AGPAT) family of enzymes have been largely identified through sequence homology, with eleven isoforms identified in both mice and humans. Interestingly, very little work has been done on the characterization of AGPAT isoform 4. In the present study, I report the functional characterization of AGPAT4 as an acyl-CoA: lysocardiolipin acyltransferase (ALCAT), which we have renamed ALCAT2. Although ALCAT2 is present in most tissues, it is abundant in multiple brain regions including olfactory bulbs, hippocampus, cerebellum, cortex, and brain stem, and is detectable in both primary neurons and glial cells. In assays performed in vitro, ALCAT2 sig...
