University of North Carolina at Charlotte

About: University of North Carolina at Charlotte is a education organization based out in Charlotte, North Carolina, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 8772 authors who have published 22239 publications receiving 562529 citations. The organization is also known as: UNC Charlotte & UNCC.

TrajGraph: A Graph-Based Visual Analytics Approach to Studying Urban Network Centralities Using Taxi Trajectory Data

Abstract: We propose TrajGraph, a new visual analytics method, for studying urban mobility patterns by integrating graph modeling and visual analysis with taxi trajectory data. A special graph is created to store and manifest real traffic information recorded by taxi trajectories over city streets. It conveys urban transportation dynamics which can be discovered by applying graph analysis algorithms. To support interactive, multiscale visual analytics, a graph partitioning algorithm is applied to create region-level graphs which have smaller size than the original street-level graph. Graph centralities, including Pagerank and betweenness, are computed to characterize the time-varying importance of different urban regions. The centralities are visualized by three coordinated views including a node-link graph view, a map view and a temporal information view. Users can interactively examine the importance of streets to discover and assess city traffic patterns. We have implemented a fully working prototype of this approach and evaluated it using massive taxi trajectories of Shenzhen, China. TrajGraph's capability in revealing the importance of city streets was evaluated by comparing the calculated centralities with the subjective evaluations from a group of drivers in Shenzhen. Feedback from a domain expert was collected. The effectiveness of the visual interface was evaluated through a formal user study. We also present several examples and a case study to demonstrate the usefulness of TrajGraph in urban transportation analysis.

Dimensions of work satisfaction as predictors of commitment type

Abstract: This study of hospital nurses (n = 154) examined the influence of dimensions of work satisfaction on types of organizational commitment. Significant results were found for the two affective commitment types tested but not for the instrumental type evaluated. The results indicate that satisfaction with professional status was a significant predictor of moral commitment. Dissatisfaction with organizational policies, autonomy, and professional status were significant predictors of alienative commitment. None of the dimensions of work satisfaction were predictors of calculative commitment. The results of this study suggest that understanding how various factors impact the nature and the form of an individual’s organizational commitment is worth the effort. If managers do not know what causes an attitude to take on a particular form, they cannot accurately predict what behavior might follow.

Membrane fatty acid and virulence changes in the viable but nonculturable state of Vibrio vulnificus.

Abstract: The nonculturable state of Vibrio vulnificus and, for comparison, that of Escherichia coli were studied in artificial-seawater microcosms at 5 degrees C. Total cell counts were monitored by acridine orange epifluorescence, metabolic activity by direct viable counts, and culturability by plate counts on selective and nonselective media. Whereas total counts remained constant, plate counts of V. vulnificus suggested nonculturability by day 24. In contrast, direct viable counts indicated significant cell viability throughout 32 days of incubation. As an indication of the metabolic changes that occurred as cells entered the state of nonrecoverability, membrane fatty acid analyses were performed. At the point of nonculturability of V. vulnificus, the major fatty acid species (C16 and C16:1) had decreased 57% from the T0 level, concomitant with the appearance of several short-chain acids. Although the bacteria were still recoverable, a similar trend was observed with E. coli. Electron microscopy of nonculturable V. vulnificus showed that the cells were rounded and reduced in size and contained fewer ribosomes. Mouse infectivity studies conducted with these cells suggested loss of virulence.

Integrating Concept Ontology and Multitask Learning to Achieve More Effective Classifier Training for Multilevel Image Annotation

Abstract: In this paper, we have developed a new scheme for achieving multilevel annotations of large-scale images automatically. To achieve more sufficient representation of various visual properties of the images, both the global visual features and the local visual features are extracted for image content representation. To tackle the problem of huge intraconcept visual diversity, multiple types of kernels are integrated to characterize the diverse visual similarity relationships between the images more precisely, and a multiple kernel learning algorithm is developed for SVM image classifier training. To address the problem of huge interconcept visual similarity, a novel multitask learning algorithm is developed to learn the correlated classifiers for the sibling image concepts under the same parent concept and enhance their discrimination and adaptation power significantly. To tackle the problem of huge intraconcept visual diversity for the image concepts at the higher levels of the concept ontology, a novel hierarchical boosting algorithm is developed to learn their ensemble classifiers hierarchically. In order to assist users on selecting more effective hypotheses for image classifier training, we have developed a novel hyperbolic framework for large-scale image visualization and interactive hypotheses assessment. Our experiments on large-scale image collections have also obtained very positive results.

Electronic window dressing: impression management with websites

Abstract: Businesses have embraced the Internet to reap economic advantages through the use of Websites Most Website design guidelines fail to address issues of branding and identity formation, focusing instead on concerns adapted from previous technologies However, many firms are not getting their desired results from the Website investments they have made following design guidelines reflecting graphic layout and system usability issues We suggest that Websites should be considered 'electronic storefronts' or public work areas providing frames of symbolic representations that create impressions of their sponsoring firms Our exploratory study shows that Websites influence potential customers' impressions of firms' legitimacy, innovation and caring, and that these impressions vary significantly across firms and industries Website visitors encounter symbols that are compared to mental models stored in memory and used to form impressions of the site and to draw inferences about the firm These inferences have previously been found to influence purchasing behavior Designers should be cognizant of these aspects of e-Business and executives should recognize the power of Web-based impression management Identity management must take center stage in creating a Web presence