New lock box solution techniques have recently been suggested by Stone and Nauss-Markland. This paper briefly discusses these new methodologies and shows how the algorithms can be combined into a third solution procedure which exploits the computational efficiency of the Stone heuristic and retains the optimizing property of the Nauss-Markland algorithm.finance, programming: integer algorithms, heuristics
Effects of climate change-driven disturbance on lake ecosystems can be subtle; indirect effects include increased nutrient loading that could impact ecosystem function. We designed a low-level fertilization experiment to mimic persistent, climate change-driven disturbances (deeper thaw, greater weathering, or thermokarst failure) delivering nutrients to arctic lakes. We measured responses of pelagic trophic levels over 12 yr in a fertilized deep lake with fish and a shallow fishless lake, compared to paired reference lakes, and monitored recovery for 6 yr. Relative to prefertilization in the deep lake, we observed a maximum pelagic response in chl a (+201%), dissolved oxygen (DO, À43%), and zooplankton biomass (+88%) during the fertilization period (2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012). Other responses to fertilization, such as water transparency and fish relative abundance, were delayed, but both ultimately declined. Phyto-and zooplankton biomass and community composition shifted with fertilization. The effects of fertilization were less pronounced in the paired shallow lakes, because of a natural thermokarst failure likely impacting the reference lake. In the deep lake there was (a) moderate resistance to change in ecosystem functions at all trophic levels, (b) eventual responses were often nonlinear, and (c) postfertilization recovery (return) times were most rapid at the base of the food web (2-4 yr) while higher trophic levels failed to recover after 6 yr. The timing and magnitude of responses to fertilization in these arctic lakes were similar to responses in other lakes, suggesting indirect effects of climate change that modify nutrient inputs may affect many lakes in the future.
Purpose
The purpose of this paper is to try to understand the process of community building that helped transform the City of Chattanooga to become one of the greenest cities in the country and why the sustainability program worked for Chattanooga.
Design/methodology/approach
In total, 30 key informants, identified through snowball sampling, were interviewed. To corroborate the interview data, numerous documents were reviewed and repeat field visits to Chattanooga and surrounding area conducted over a period of three-and-a-half years. Interview data were analyzed using MAXQDA qualitative data analysis software.
Findings
Findings show that the transformation process from “the dirtiest city in America” to “green city” was mainly a community agenda. Led by concerned private citizens and visionaries, Chattanooga went through aggressive community mobilization, citizen empowerment and participation in environmental improvement, building of social capital and economic revitalization.
Research limitations/implications
Research limitations include under coverage and researcher bias.
Practical implications
Lessons for cities that share the same industrial history as Chattanooga.
Social implications
Community-building and community participation can work in a collectivist culture.
Originality/value
The lead author collected the data, conducted analysis and did all the writing with mentoring from the co-authors.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.