49 research outputs found
Activities, Interests, And Opinions Of Online Shoppers And Non-Shoppers
Internet shopping represents the launch of a new industry with corresponding levels of praise and concern. It is both the “golden child” for innovative net users, and the “evil empire” for anxious brick-and-mortar retailers. Online purchasing is growing at a dramatic rate yet the expectation for an explosion of Internet shopping has not occurred; its market share is small, at just under two percent of total U.S. retail spending. This study has been designed to explore why online shopping is growing so fast among some households, and so slowly among others. It focuses on characterizing the fundamental motivators or satisfiers of e-retail shopping, along with its dis-satisfiers and de-motivators. And it examines lifestyles of both Web shoppers and non-shoppers to find that these are not homogeneous groups at all, but discrete market segments, each seeking distinctive benefits from the Internet. It examines the lifestyle characteristics of online households. By means of a U.S. national probability sample of online heads-of-households, this descriptive research provides a lifestyle perspective of who is using the Internet to shop, who does not shop, and why. It is hypothesized and shown that, compared with online non-shoppers, online shoppers are younger, wealthier, have higher computer literacy, spend more time on their computer, spend more time on the Internet, and find online shopping to be easier and more entertaining. It is further reported that shoppers and non-shoppers are involved in different online activities, and have different attitudes and opinions toward the Internet and online use. Each group is profiled and marketing implications are discussed
A Demonstration of Spectral and Spatial Interferometry at THz Frequencies
A laboratory prototype spectral/spatial interferometer has been constructed
to demonstrate the feasibility of the double Fourier technique at Far Infrared
(FIR) wavelengths (0.15 - 1 THz). It is planned to use this demonstrator to
investigate and validate important design features and data processing methods
for future astronomical FIR interferometer instruments. In building this
prototype we have had to address several key technologies to provide an end-end
system demonstration of this double Fourier interferometer. We report on the
first results taken when viewing single slit and double slit sources at the
focus of a large collimator used to simulate real sources at infinity. The
performance of the prototype instrument for these specific field geometries is
analyzed to compare with the observed interferometric fringes and to
demonstrate image reconstruction capabilities.Comment: Accepted for publication in Applied Optic
Reduction Algorithms for the Multiband Imaging Photometer for Spitzer
We describe the data reduction algorithms for the Multiband Imaging
Photometer for Spitzer (MIPS) instrument. These algorithms were based on
extensive preflight testing and modeling of the Si:As (24 micron) and Ge:Ga (70
and 160 micron) arrays in MIPS and have been refined based on initial flight
data. The behaviors we describe are typical of state-of-the-art infrared focal
planes operated in the low backgrounds of space. The Ge arrays are bulk
photoconductors and therefore show a variety of artifacts that must be removed
to calibrate the data. The Si array, while better behaved than the Ge arrays,
does show a handful of artifacts that also must be removed to calibrate the
data. The data reduction to remove these effects is divided into three parts.
The first part converts the non-destructively read data ramps into slopes while
removing artifacts with time constants of the order of the exposure time. The
second part calibrates the slope measurements while removing artifacts with
time constants longer than the exposure time. The third part uses the
redundancy inherit in the MIPS observing modes to improve the artifact removal
iteratively. For each of these steps, we illustrate the relevant laboratory
experiments or theoretical arguments along with the mathematical approaches
taken to calibrate the data. Finally, we describe how these preflight
algorithms have performed on actual flight data.Comment: 21 pages, 16 figures, PASP accepted (May 2005 issue), version of
paper with full resolution images is available at
http://dirty.as.arizona.edu/~kgordon/papers/PS_files/mips_dra.pd
Segmenting Internet shoppers based on their Web-usage-related lifestyle: a cross-cultural validation
A Space-based Far Infrared Interferometer (FIRI) instrument simulator and test-bed implementation
FIRI (Far Infrared Interferometer) is a concept for a spatial and spectral interferometer with an operating wavelength range 25-300 μm and sub-arcsecond angular resolution, and is based in the combination of two well-known techniques, Stellar Interferometry and Fourier Transform Spectroscopy to achieve high spectral and spatial resolution in the Far Infrared. The resulting technique is called Double Fourier Spatio-Spectral Interferometry (Mariotti and Ridgway 1988). With increased spatial and spectral resolution a number of interesting science cases such as the formation and evolution of AGN and the characterization of gas, ice and dust in disks undergoing planetary formation, among others, can be investigated. Here the current status of the design of the FIRI system via an instrument simulator is presented, as well as the results of a test-bed implementation.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only