117 research outputs found

    Digital images forever: implementing an imaging system in a cultural institution

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    This paper deals with the decision-making and challenges that arose out of the implementation of a large-scale digital imaging project by the Powerhouse Museum. With the implementation of the Powerhouse's Imaging Project came the creation of its Image Centre. This paper discusses its role, the services provided, preparation of its equipment and the procedures developed for capturing, storing and retrieving images. Most importantly, the issues of technological change upon an image archive are discussed. The Powerhouse Museum's Imaging System, as it stands today, does what was intended. It delivers images and related data to staff and public for the purposes of research, promotion, education and more. The Museum's Image Centre was set up to scan, manipulate, print and archive images. This Centre has evolved into a high-resolution digital imaging service and continues to create and upload images to the Imaging System. However, without a plan for constant review and update, even archives of beautifully scanned images and comprehensive data are worthless if those archives cannot be reused because the mechanisms for accessing the media - or the applications that they run on, have become obsolete. The Museum's next step, therefore, is a policy for regular re-evaluation.Hosted by the Scholarly Text and Imaging Service (SETIS), the University of Sydney Library, and the Research Institute for Humanities and Social Sciences (RIHSS), the University of Sydney

    Digital images forever: implementing an imaging system in a cultural institution

    Get PDF
    This paper deals with the decision-making and challenges that arose out of the implementation of a large-scale digital imaging project by the Powerhouse Museum. With the implementation of the Powerhouse's Imaging Project came the creation of its Image Centre. This paper discusses its role, the services provided, preparation of its equipment and the procedures developed for capturing, storing and retrieving images. Most importantly, the issues of technological change upon an image archive are discussed. The Powerhouse Museum's Imaging System, as it stands today, does what was intended. It delivers images and related data to staff and public for the purposes of research, promotion, education and more. The Museum's Image Centre was set up to scan, manipulate, print and archive images. This Centre has evolved into a high-resolution digital imaging service and continues to create and upload images to the Imaging System. However, without a plan for constant review and update, even archives of beautifully scanned images and comprehensive data are worthless if those archives cannot be reused because the mechanisms for accessing the media - or the applications that they run on, have become obsolete. The Museum's next step, therefore, is a policy for regular re-evaluation.Hosted by the Scholarly Text and Imaging Service (SETIS), the University of Sydney Library, and the Research Institute for Humanities and Social Sciences (RIHSS), the University of Sydney

    First cohomology groups for finite groups of Lie type in defining characteristic

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    Let G be a finite group of Lie type, defined over a field k of characteristic p > 0 . We find explicit bounds for the dimensions of the first cohomology groups for with coefficients in simple kG-modules. We proceed by bounding the number of composition factors of Weyl modules for simple algebraic groups independently of P and using this to deduce bounds for the 1-cohomology of simple algebraic groups. If γl denotes the (finite) maximum of the dimensions of the 1-cohomology groups over all Lie groups of rank l we find bounds for the growth rate of the sequence. {γl}We show that log γl is O(l3log l

    Diffusion versus linear ballistic accumulation: different models but the same conclusions about psychological processes?

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    Quantitative models for response time and accuracy are increasingly used as tools to draw conclusions about psychological processes. Here we investigate the extent to which these substantive conclusions depend on whether researchers use the Ratcliff diffusion model or the Linear Ballistic Accumulator model. Simulations show that the models agree on the effects of changes in the rate of information accumulation and changes in non-decision time, but that they disagree on the effects of changes in response caution. In fits to empirical data, however, the models tend to agree closely on the effects of an experimental manipulation of response caution. We discuss the implications of these conflicting results, concluding that real manipulations of caution map closely, but not perfectly to response caution in either model. Importantly, we conclude that inferences about psychological processes made from real data are unlikely to depend on the model that is used

    Effects of kefir on coccidial oocysts excretion and performance of dairy goat kids following weaning

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    The aim of this study was to investigate effects of kefir, a traditional source of probiotic, on coccidial oocysts excretion and on the performance of dairy goat kids following weaning. Twin kids were randomly allocated to one of two groups at weaning. Kids of the first group received 20 ml of kefir daily for 6 weeks (KEF), while kids in the control group were given a placebo (CON). Individual faecal samples were regularly (n = 18 per kid) taken to quantify the number of coccidial oocysts per gram of faeces (OpG). There were no differences between the groups in terms of body weight development (P > 0.05) and feed consumption. Kids of both groups were not able to consume enough feed to meet their nutrient requirements during the first 3 weeks following weaning. KEF had a lower frequency of OpG positive samples than CON (P = 0.043). Kefir did not affect the maximum oocyst excretion and age of the kids at the highest oocyst excretion (P > 0.05). KEF shed numerically 35% lower coccidial oocysts than the controls, which corresponded to a statistical tendency (P = 0.074) in lowering Log-OpG in comparison to CON. While KEF had a lower frequency of OpG positive samples and tended to shed lower OPG by around one-third, the frequency of diarrhea, level of highest oocyst excretion, and performance of the kids remained unaffected. Therefore, it is concluded that overall effects of kefir do not have a significant impact on sub-clinical infection and performance in weaned kids under relatively high-hygienic farming conditions

    Measures of the Consumer Food Store Environment: A Systematic Review of the Evidence 2000–2011

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    Description of the consumer food environment has proliferated in publication. However, there has been a lack of systematic reviews focusing on how the consumer food environment is associated with the following: (1) neighborhood characteristics; (2) food prices; (3) dietary patterns; and (4) weight status. We conducted a systematic review of primary, quantitative, observational studies, published in English that conducted an audit of the consumer food environment. The literature search included electronic, hand searches, and peer-reviewed from 2000 to 2011. Fifty six papers met the inclusion criteria. Six studies reported stores in low income neighborhoods or high minority neighborhoods had less availability of healthy food. While, four studies found there was no difference in availability between neighborhoods. The results were also inconsistent for differences in food prices, dietary patterns, and weight status. This systematic review uncovered several key findings. (1) Systematic measurement of determining availability of food within stores and store types is needed; (2) Context is relevant for understanding the complexities of the consumer food environment; (3) Interventions and longitudinal studies addressing purchasing habits, diet, and obesity outcomes are needed; and (4) Influences of price and marketing that may be linked with why people purchase certain items

    Association between neighborhood need and spatial access to food stores and fast food restaurants in neighborhoods of Colonias

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    Objective To determine the extent to which neighborhood needs (socioeconomic deprivation and vehicle availability) are associated with two criteria of food environment access: 1) distance to the nearest food store and fast food restaurant and 2) coverage (number) of food stores and fast food restaurants within a specified network distance of neighborhood areas of colonias, using ground-truthed methods. Methods Data included locational points for 315 food stores and 204 fast food restaurants, and neighborhood characteristics from the 2000 U.S. Census for the 197 census block group (CBG) study area. Neighborhood deprivation and vehicle availability were calculated for each CBG. Minimum distance was determined by calculating network distance from the population-weighted center of each CBG to the nearest supercenter, supermarket, grocery, convenience store, dollar store, mass merchandiser, and fast food restaurant. Coverage was determined by calculating the number of each type of food store and fast food restaurant within a network distance of 1, 3, and 5 miles of each population-weighted CBG center. Neighborhood need and access were examined using Spearman ranked correlations, spatial autocorrelation, and multivariate regression models that adjusted for population density. Results Overall, neighborhoods had best access to convenience stores, fast food restaurants, and dollar stores. After adjusting for population density, residents in neighborhoods with increased deprivation had to travel a significantly greater distance to the nearest supercenter or supermarket, grocery store, mass merchandiser, dollar store, and pharmacy for food items. The results were quite different for association of need with the number of stores within 1 mile. Deprivation was only associated with fast food restaurants; greater deprivation was associated with fewer fast food restaurants within 1 mile. CBG with greater lack of vehicle availability had slightly better access to more supercenters or supermarkets, grocery stores, or fast food restaurants. Increasing deprivation was associated with decreasing numbers of grocery stores, mass merchandisers, dollar stores, and fast food restaurants within 3 miles. Conclusion It is important to understand not only the distance that people must travel to the nearest store to make a purchase, but also how many shopping opportunities they have in order to compare price, quality, and selection. Future research should examine how spatial access to the food environment influences the utilization of food stores and fast food restaurants, and the strategies used by low-income families to obtain food for the household

    The Quality of Response Time Data Inference: A Blinded, Collaborative Assessment of the Validity of Cognitive Models

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    Most data analyses rely on models. To complement statistical models, psychologists have developed cognitive models, which translate observed variables into psychologically interesting constructs. Response time models, in particular, assume that response time and accuracy are the observed expression of latent variables including 1) ease of processing, 2) response caution, 3) response bias, and 4) non-decision time. Inferences about these psychological factors, hinge upon the validity of the models’ parameters. Here, we use a blinded, collaborative approach to assess the validity of such model-based inferences. Seventeen teams of researchers analyzed the same 14 data sets. In each of these two-condition data sets, we manipulated properties of participants’ behavior in a two-alternative forced choice task. The contributing teams were blind to the manipulations, and had to infer what aspect of behavior was changed using their method of choice. The contributors chose to employ a variety of models, estimation methods, and inference procedures. Our results show that, although conclusions were similar across different methods, these "modeler’s degrees of freedom" did affect their inferences. Interestingly, many of the simpler approaches yielded as robust and accurate inferences as the more complex methods. We recommend that, in general, cognitive models become a typical analysis tool for response time data. In particular, we argue that the simpler models and procedures are sufficient for standard experimental designs. We finish by outlining situations in which more complicated models and methods may be necessary, and discuss potential pitfalls when interpreting the output from response time models
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