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.

Efficient interference-aware TDMA link scheduling for static wireless networks

Abstract: We study efficient link scheduling for a multihop wireless network to maximize its throughput. Efficient link scheduling can greatly reduce the interference effect of close-by transmissions. Unlike the previous studies that often assume a unit disk graph model, we assume that different terminals could have different transmission ranges and different interference ranges. In our model, it is also possible that a communication link may not exist due to barriers or is not used by a predetermined routing protocol, while the transmission of a node always result interference to all non-intended receivers within its interference range. Using a mathematical formulation, we develop synchronized TDMA link schedulings that optimize the networking throughput. Specifically, by assuming known link capacities and link traffic loads, we study link scheduling under the RTS/CTS interference model and the protocol interference model with fixed transmission power. For both models, we present both efficient centralized and distributed algorithms that use time slots within a constant factor of the optimum. We also present efficient distributed algorithms whose performances are still comparable with optimum, but with much less communications. Our theoretical results are corroborated by extensive simulation studies.

An Exploratory Study of Posttraumatic Growth in Children Following a Natural Disaster

Abstract: This study extends L. G. Calhoun and R. G. Tedeschi's (1998) model of posttraumatic growth (PTG), positive change resulting from the struggle with trauma, to children by exploring the construct among youngsters who experienced Hurricane Floyd and the subsequent flooding. Despite burgeoning interest in PTG, few studies have examined the phenomenon among non-adults. This first systematic study of PTG in children explores hypothesized linkages among PTG and social support, competency beliefs, and ruminative thinking. Results suggest that competency beliefs relate to PTG and that a supportive social environment and ruminative thinking are associated with positive competency beliefs. Contrary to expectations, social support did not relate to rumination. Findings testify to the merit of studying the PTG process in children. Clinical implications and future directions are considered.

Leveraging Family‐Based Brand Identity to Enhance Firm Competitiveness and Performance in Family Businesses*

Abstract: Drawing on the family-embeddedness perspective on entrepreneurship and the resource-based-view of the firm, we investigate how the promotion of family-based brand identity influences competitive orientation (customer versus product) and firm performance in family businesses. Applying structural equation modeling to survey data collected from leaders of 218 family businesses, we demonstrate that developing a family-based brand identity positively contributes to firm performance (growth and profitability) indirectly, via a customer-centric orientation. In contrast, attempts to leverage family-based brand identity via a product-centric orientation do not impact firm performance. Our results suggest that family-based brand identity enhances the family business’ ability to persuade customers to make purchasing decisions based on the perceived attributes of the seller. As a result, we contribute to the discussions centered on how to optimize the intricate synergy between family and business.

Environmental issues from coal mining and their solutions

Abstract: The environmental challenges from coal mining include coal mine accidents, land subsidence, damage to the water environment, mining waste disposal and air pollution. These are either environmental pollution or landscape change. A conceptual framework for solving mine environmental issues is proposed. Clean processes, or remediation measures, are designed to address environmental pollution. Restoration measures are proposed to handle landscape change. The total methane drainage from 56 Chinese high methane concentration coal mines is about 101.94 million cubic meters. Of this methane, 19.32 million, 35.58 million and 6.97 million cubic meters are utilized for electricity generation, civil fuel supplies and other industrial purposes, respectively. About 39% of the methane is emitted into the atmosphere. The production of coal mining wastes can be decreased 10% by reuse of mining wastes as underground fills, or by using the waste as fuel for power plants or for raw material to make bricks or other infrastructure materials. The proper use of mined land must be decided in terms of local physical and socio-economical conditions. In European countries more than 50% of previously mined lands are reclaimed as forest or grass lands. However, in China more than 70% of the mined lands are reclaimed for agricultural purposes because the large population and a shortage of farmlands make this necessary. Reconstruction of rural communities or native residential improvement is one environmental problem arising from mining. We suggest two ways to reconstruct a farmer's house in China.