University of Rhode Island

About: University of Rhode Island is a education organization based out in Kingston, Rhode Island, United States. It is known for research contribution in the topics: Population & Bay. The organization has 11464 authors who have published 22770 publications receiving 841066 citations. The organization is also known as: URI & Rhode Island College of Agriculture and the Mechanic Arts.

Switching to electronic stores: consumer characteristics and the perception of shopping benefits

Abstract: The shift from physical (brick and mortar) stores and hard copy catalog stores toward electronic stores (e‐tailing) may be seen as a continuous innovation building on past changes brought about by in‐home shopping methods such as catalog, TV and direct mail. Why are e‐tailers then having such difficulty retaining their customers? In this paper, we examine the influence of consumer characteristics on perception of shopping benefits associated with electronic and physical shopping. Based on a mail survey of upscale US households, the empirical study finds the two shopping formats to be clearly different from each other in terms of perceived shopping benefits. The data supports the influence of individual characteristics (such as age, household income and family composition) as well as past behaviors on the shopping benefits associated with the two modes of shopping.

Two Years in the Life of a Mediterranean Salt Lens

Abstract: A lens of Mediterranean water (Meddy) was tracked in the eastern North Atlantic for two years with SOFAR floats. The Meddy was first found between the Canary Islands and the Azores in October 1984. It center moved in an irregular pattern, at speeds of a few cm s−1, and translated 1100 km to the south in two years. This Meddy was surveyed four times by CTD and velocity profilers, and once with the microstructure profiler EPSONDE. When observed during the first two surveys the Meddy had a core that was stably and smoothly stratified in both salinity and temperature, nearly uniform in the horizontal, and was saltier than the surrounding ocean by 0.65 psu. The Meddy was eroded from its edges, top and bottom, and lost salt and hat with an e-folding time of about one year. The salinity at the center remained at its original value during the first year and decreased during the second year. Evidence was seen for mixing by lateral intrusions, double diffusion, and turbulence; the intrusions are thought to...

Grazing, respiration, excretion, and growth rates of tintinnids1

Abstract: Clearance, ingestion, and growth rates of two coastal tintinnid ciliates were measured in batch culture as a function of temperature and phytoplankton concentration. Oxygen consumption and ammonium excretion rates were determined at food concentrations which supported maximum growth rates at each temperature. Clearance, ingestion, respiration, excretion, and growth rates of both species increased with temperature. Clearing rates declined with increasing phytoplankton abundance. Ingestion and growth rates increased asymptotically with phytoplankton abundance and declined at high food concentrations. Gross growth efficiency was highest at phytoplankton concentrations which supported maximum growth rates. Over a range of temperatures, respiration and excretion were linearly related and exhibited significant linear relationships with ingestion and curvilinear relationships with growth. 0 : N ratios were 4-7, assuming an RQ of 1 .O. The metabolic data were combined with previous measurements of in situ production by tintinnids to estimate their potential carbon requirements and NH,+ regeneration in Narragansett Bay, Rhode Island. Tintinnids ingested a carbon equivalent of 16-26% of the total annual net primary production and 32-52% of < IO-urn nanonlankton oroduction. Nitrogen excretion was sufficient to support 1 l18% of net primary production.

Performance analysis for DOA estimation algorithms: unification, simplification, and observations

Abstract: Subspace based direction-of-arrival (DOA) estimation has motivated many performance studies, but limitations such as the assumption of an infinite amount of data and analysis of individual algorithms generally exist in these performance studies. The authors have previously proposed a unified performance analysis based on a finite amount of data and achieved a tractable expression for the mean-squared DOA estimation error for the multiple signal classification (MUSIC). Min-Norm, estimation of signal parameters using rotational invariance techniques (ESPRIT), and state-space realization algorithms. However, this expression uses the singular values and vectors of a data matrix, which are obtained by the highly nonlinear transformation of the singular value decomposition (SVD). Thus the effects of the original data parameters such as numbers of sensors and snapshots, source coherence and separations were not explicitly analyzed. The authors unify and simplify this previous result and derive a unified expression based on the original data parameters. They analytically observe the effects of these parameters on the estimation error. >