Sensitivity analysis of a land surface scheme using multicriteria methods

Attempts to model surface-atmosphere interactions with greater physical realism have resulted in complex land surface schemes (LSS) with large numbers of parameters. A companion paper describes a multicriteria calibration procedure for extracting plot-scale estimates of the preferred ranges of these parameters from the various observational data sets that are now available. A complementary procedure is presented in this paper that provides an objective determination of the multicriteria sensitivity of the modeled variables to the parameters, thereby allowing the number of calibration parameters and hence the computational effort to be reduced. Two case studies are reported for the BATS model using data sets of typical quality but very different location and climatological regime (ARM-CART and Tucson). The sensitivity results were found to be consistent with the physical properties of the different environments, thereby supporting the reasonableness of the model formulation. Further, when the insensitive parameters are omitted from the calibration process, there is little degradation in the quality of the model description and little change in the preferred range of the remaining parameters. Copyright 1999 by the American Geophysical Union

Parameter estimation of a land surface scheme using multicriteria methods

Attempts to create models of surface-atmosphere interactions with greater physical realism have resulted in land surface schemes (LSS) with large numbers of parameters. The hope has been that these parameters can be assigned typical values by inspecting the literature. The potential for using the various observational data sets that are now available to extract plot-scale estimates for the parameters of a complex LSS via advanced parameter estimation methods developed for hydrological models is explored in this paper. Results are reported for two case studies using data sets of typical quality but very different location and climatological regime (ARM-CART and Tucson). The traditional single-criterion methods were found to be of limited value. However, a multicriteria approach was found to be effective in constraining the parameter estimates into physically plausible ranges when observations on at least one appropriate heat flux and one properly selected state variable are available. Copyright 1999 by the American Geophysical Union

Triadophilia: A Special Corner in the Landscape

It is well known that there are a great many apparently consistent vacua of string theory. We draw attention to the fact that there appear to be very few Calabi--Yau manifolds with the Hodge numbers h^{11} and h^{21} both small. Of these, the case (h^{11}, h^{21})=(3,3) corresponds to a manifold on which a three generation heterotic model has recently been constructed. We point out also that there is a very close relation between this manifold and several familiar manifolds including the `three-generation' manifolds with \chi=-6 that were found by Tian and Yau, and by Schimmrigk, during early investigations. It is an intriguing possibility that we may live in a naturally defined corner of the landscape. The location of these three generation models with respect to a corner of the landscape is so striking that we are led to consider the possibility of transitions between heterotic vacua. The possibility of these transitions, that we here refer to as transgressions, is an old idea that goes back to Witten. Here we apply this idea to connect three generation vacua on different Calabi-Yau manifolds.Comment: 41 pages 4 pdf figures, one is large. Improved discussion of the Gross-Popescu manifolds, Figure 4 added, additions to Table 1 and other minor correction

AN INVESTIGATION OF QR CODE USE IN INDIANAPOLIS FOOD AND BEVERAGE INDUSTRY

poster abstractAccording Mostyn, market research specialist, (2012), global smartphone shipments increased by 62.7 percent in 2011. In the US, smart phones are gaining in popularity. A Quick Response (QR) code is a type of barcode that can be read by smart phones. It can be used to link print to other interactive information (e.g. access URLs, send an e-coupon, download video, etc.). The QR code is considered new technology in food and beverage industry and there is limited information about its use. Nation’s Restaurant News (2011) reported that QR codes are slowly being used to promote restaurants, such as Taco Bell and Boudin Bakery. The purpose of this research is to investi-gate if and how QR codes are being used in the Indianapolis restaurant in-dustry. The study will provide baseline information and the potential for QR code use in the Indianapolis restaurants. Effective use of QR codes may even influence consumer choices and/or company profitability. Archival and web search in addition to interviews with restaurant managers is the method of data collection. Approximately 10 restaurants in the Indianapolis area will be sampled. Some interview questions include: What is the purpose of using QR code? And what are the advantages and disadvantages of using QR codes? The study is currently in the data collection phase. Preliminary results sug-gest that QR code use is in its infancy in Indianapolis, when compared to restaurants in Chicago or Vancouver. Also, more franchise restaurants and big chain restaurants have embraced this technology than the smaller family owned restaurants. QR codes are typically used for menu nutrition and res-taurant history information, marketing via coupons, and customer surveys. This study was sponsored by the IUPUI Undergraduate Research Opportunities Program

Wave attenuation at a salt marsh margin: A case study of an exposed coast on the Yangtze estuary

To quantify wave attenuation by (introduced) Spartina alterniflora vegetation at an exposed macrotidal coast in the Yangtze Estuary, China, wave parameters and water depth were measured during 13 consecutive tides at nine locations ranging from 10 m seaward to 50 m landward of the low marsh edge. During this period, the incident wave height ranged from <0.1 to 1.5 m, the maximum of which is much higher than observed in other marsh areas around the world. Our measurements and calculations showed that the wave attenuation rate per unit distance was 1 to 2 magnitudes higher over the marsh than over an adjacent mudflat. Although the elevation gradient of the marsh margin was significantly higher than that of the adjacent mudflat, more than 80% of wave attenuation was ascribed to the presence of vegetation, suggesting that shoaling effects were of minor importance. On average, waves reaching the marsh were eliminated over a distance of similar to 80 m, although a marsh distance of >= 100 m was needed before the maximum height waves were fully attenuated during high tides. These attenuation distances were longer than those previously found in American salt marshes, mainly due to the macrotidal and exposed conditions at the present site. The ratio of water depth to plant height showed an inverse correlation with wave attenuation rate, indicating that plant height is a crucial factor determining the efficiency of wave attenuation. Consequently, the tall shoots of the introduced S. alterniflora makes this species much more efficient at attenuating waves than the shorter, native pioneer species in the Yangtze Estuary, and should therefore be considered as a factor in coastal management during the present era of sea-level rise and global change. We also found that wave attenuation across the salt marsh can be predicted using published models when a suitable coefficient is incorporated to account for drag, which varies in place and time due to differences in plant characteristics and abiotic conditions (i.e., bed gradient, initial water depth, and wave action).