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Moraga, CA, United States

Saint Mary's College of California is a private, coeducational college located in Moraga, California, United States, a small suburban community about 10 miles east of Oakland and 20 miles east of San Francisco. It has a 420-acre campus in the Moraga hills Wikipedia.

Wagner M.R.,Saint Marys College of California
Operations Research Letters

We study inventory management problems where demands are revealed incrementally and procurement decisions must be made before the demands are realized. There are no probabilistic distributions nor non-trivial bounds to characterize demands. We consider two cost minimization problems: (1) perishable products with lost sales and (2) durable products with backlogged demand. In both problems, costs are period dependent. These problems are analyzed by utilizing linear-fractional programming and duality theory. Structural results are proved and then developed into practical strategies. © 2011 Elsevier B.V. All rights reserved. Source

Wagner M.R.,Saint Marys College of California
Mathematics of Operations Research

We study profit maximization in inventory control problems where demands are unknown. Neither probabilistic distributions nor sets are available to characterize the unknown demand parameters. Therefore, we adopt an online optimization perspective for our analysis. The usual competitive ratio is not well defined for the problems we analyze; consequently, we introduce a new worst-case metric that is suitable. We consider two inventory management frameworks: (1) perishable products with lost sales and (2) durable products with backlogged demand. We consider both finite and infinite planning horizons. We design best-possible online procurement strategies for all cases. © 2010 INFORMS. Source

Burley J.D.,Saint Marys College of California | Bytnerowicz A.,U.S. Department of Agriculture
Atmospheric Environment

Surface ozone concentrations are presented for four high-elevation sites along a north-south transect along the spine of the White Mountains and a fifth site located at lower elevation approximately 15km to the west on the floor of the Owens Valley. The ozone data, which were collected from mid-June through mid-October of 2009, include results from two sites, White Mountain Summit (4342m elevation) and Barcroft Station (3783m), that are believed to be higher in elevation than any previously investigated sampling locations in North America. Average daily ozone values from the five sampling sites display similar day-to-day and week-to-week temporal fluctuations, which suggest that the sites are experiencing the same regional-scale background patterns in air quality and meteorology. Ozone concentrations increase with increasing elevation, consistent with findings from prior studies in Europe and North America. A linear elevation gradient of +0.0042ppbm-1 is obtained for July 15-August 15, but analogous gradients for August 15-September 15 and September 15-October 15 show reduced linearity and possibly the onset of a plateau in ozone concentrations for elevations above 2000m. Average diurnal cycle magnitudes decrease with increasing elevation, falling from ∼25-35ppb for the Owens Valley site to ∼3-7ppb at three of the four high-elevation sites. Diurnal cycle magnitudes decrease (or remain roughly constant) at the non-Summit sites during the progression from mid-July to mid-October, but the magnitude of the diurnal cycle at the Summit increases from ∼3ppb to ∼7ppb over this same time frame. This latter result is inconsistent with results from previous investigations at other alpine sites, and may indicate the presence of local, topography-influenced mixing dynamics that are unique to the White Mountains. High hourly ozone concentrations at White Mountain Summit are found to correlate with 72-hour HYSPLIT back-trajectories that reflect enhanced levels of ozone transport from polluted regions (such as the Central Valley of California) or meteorological conditions that are favorable for ozone production. Low ozone concentrations at the Summit are found to correlate with HYSPLIT back-trajectories that reflect reduced levels of ozone transport from polluted areas or meteorological conditions that are unfavorable for ozone production. © 2011 Elsevier Ltd. Source

Nathanson M.,Saint Marys College of California
Physical Review A - Atomic, Molecular, and Optical Physics

We show that there exist sets of three mutually orthogonal d-dimensional maximally entangled states which cannot be perfectly distinguished using one-way local operations and classical communication (LOCC) for arbitrarily large values of d. This contrasts with several well-known families of maximally entangled states, for which any three states can be perfectly distinguished. We then show that two-way LOCC is sufficient to distinguish these examples. We also show that any three mutually orthogonal d-dimensional maximally entangled states can be perfectly distinguished using measurements with a positive partial transpose (PPT) and can be distinguished with one-way LOCC with high probability. These results circle around the question of whether there exist three maximally entangled states which cannot be distinguished using the full power of LOCC; we discuss possible approaches to answer this question. © 2013 American Physical Society. Source

Bandyopadhyay S.,Bose Institute of India | Nathanson M.,Saint Marys College of California
Physical Review A - Atomic, Molecular, and Optical Physics

One of the many interesting features of quantum nonlocality is that the states of a multipartite quantum system cannot always be distinguished as well by local measurements as they can when all quantum measurements are allowed. In this work, we characterize the distinguishability of sets of multipartite quantum states when restricted to separable measurements, those which contain the class of local measurements but nevertheless are free of entanglement between the component systems. We consider two quantities: the separable fidelity, a truly quantum quantity, which measures how well we can "clone" the input state, and the classical probability of success, which simply gives the optimal probability of identifying the state correctly. We obtain lower and upper bounds on the separable fidelity and give several examples in the bipartite and multipartite settings where these bounds are optimal. Moreover the optimal values in these cases can be attained by local measurements. We further show that for distinguishing orthogonal states under separable measurements, a strategy that maximizes the probability of success is also optimal for separable fidelity. We point out that the equality of fidelity and success probability does not depend on an using the optimal strategy, only on the orthogonality of the states. To illustrate this, we present an example where two sets (one consisting of orthogonal states and the other nonorthogonal states) are shown to have the same separable fidelity even though the success probabilities are different. © 2013 American Physical Society. Source

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