The role of historical influences in patterning forest landscapes was explored in a case study of forest structure change in the American Southwest. A group of ponderosa pine trees was destructively sampled and year o...
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The role of historical influences in patterning forest landscapes was explored in a case study of forest structure change in the American Southwest. A group of ponderosa pine trees was destructively sampled and year of germination identified in order to assess the strength and nature of the climate signal in influencing ponderosa pine germination in this century. A novel methodology for estimating year of germination in woody species by identifying the root-shoot boundary appears to be promising. Both rare seasonal and interannual climatic factors and a unique set of circumstances associated with anthropogenic disturbances played a role in shaping a germination pulse early in the 20th century. A cohort originating in 1919 captured available space and, barring major disturbance, will dominate forest structure at the site for centuries. Such rare germination events support the view that forest communities are essentially dynamic and non-equilibrial over the long-term.
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Advertising Rate InformationCLASSIFICATIONSPositions open—placement bureaus, industrial positions, pharmaceutical positions, and academic positions. Situations wanted—members, nonmembers, student and national affiliates, retired ***:Published weekly, issued every Monday. Mailed Friday preceding date of *** Date for Classified Ads:Standard Set Ads-Thursday, 10 a.m. 18 days preceding publication date. Display Ads—Monday, 2 weeks preceding publication date, No extensions. Cancellations must be received 14 days in advance of publication date (except legal holidays.)ACS MEMBER RATES"Situations Wanted" advertisements wilt be classified by the chemical field designated by the members, if not designated, placement will be determined by the first word of the text *** MEMBERS"Situations Wanted" advertisements placed by employed ACS members and affiliates are accepted at $6,60 a line per insertion, no minimum charge. State ACS membership status and mail advertisements to: Chemical & Engineering News, Classified Advertising, 676 East Swedesford Road, Suite 202, Wayne, PA 19087 1612. Phone: {610} 964-8061; ...
The first of a series of illustrated articles giving a general account of the most important of the many transferences of industries recently effected. (Serial. 1st part) (2300 w.)
The first of a series of illustrated articles giving a general account of the most important of the many transferences of industries recently effected. (Serial. 1st part) (2300 w.)
Diacritics32.2 (2002) 3-19In October 2000, just a few weeks before the US presidential election, a young, fashionable, handsome man handed me a political leaflet while I crossed Christopher Street in Greenwich Village...
Diacritics32.2 (2002) 3-19In October 2000, just a few weeks before the US presidential election, a young, fashionable, handsome man handed me a political leaflet while I crossed Christopher Street in Greenwich Village. I didn't give it much thought at the time (apart from noticing that the boy was kind of cute): I was in transit toward the 4thStreet subway station and the Port Authority where I would catch the bus back to Cornell. When I decided to write a review essay on the current state of poststructuralism, Marxism, and queer theory through the lens of the two books listed above, I discovered I had lost the pamphlet, certain that my hostile reaction to what I considered its fundamental conservatism and trendy political correctness had unconsciously caused its mysterious *** I rediscovered the leaflet in the chaos of my move away from Ithaca, I realized that my relation to it had been hysterical: I was reluctant to address its traumatic content, unwilling to excavate my multiple frustrations at the apparent impossibility of being a homosexual and a socialist in America. And yet I couldn't really forget about it either: though not an American citizen and therefore unable to vote, I found myself equally unable simply to dismiss the leaflet as a mere inconsequential symptom of the pseudo-democracy that America has always been, or unequivocally to endorse the snooty CBC/Queen Street condescension of my fellow Canadian Lefties toward the primitive, superficial, liberal (in the worst psychologistic sense), irremediably ideological, and thoroughly depressing state of American political discourse. "Those poor Americans," the far-from-irrelevant logic goes. "They either unquestioningly submit to the individualistic fantasy of the American Dream in order to participate in the 'political process,' or they become hermetically imprisoned in their pseudo-political anti-statist minoritarianism, too cool and too radical to condescend to the public sphere." After s
A nonlinear model for the surge tank of Sibanye-Stillwater’s Platinum tailings treatment plant is derived and linearised. Three controllers (two classical feedback and one model predictive controller (MPC)) are prese...
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A nonlinear model for the surge tank of Sibanye-Stillwater’s Platinum tailings treatment plant is derived and linearised. Three controllers (two classical feedback and one model predictive controller (MPC)) are presented for control of the plant, and it is shown that a decoupled proportional-integral (PI) control structure, as would be employed in practice, performs the worst, while a nonlinear MPC controller provides the best performance. To illustrate an access economy model concept for industrial process control, a cloud platform to facilitate the competition between various controllers is presented and a scenario given with the three controllers competing to control the surge tank process. The platform is shown to provide the plant access to a controller that performs better than what is available locally.
Large-scale epidemiological and population data provide opportunities to identify subgroups of people who are at risk of disease or exposed to adverse environments. Clustering algorithms are popular data-driven tools ...
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Large-scale epidemiological and population data provide opportunities to identify subgroups of people who are at risk of disease or exposed to adverse environments. Clustering algorithms are popular data-driven tools to identify these subgroups;however, relying exclusively on algorithms may not produce the best results if the dataset does not have a clustered structure. For this reason, we propose a framework (the R-library Numero) that combines the self-organizing map algorithm, permutation analysis for statistical evidence and a final expert-driven subgrouping step. We used Numero to define subgroups in two examples without an obvious clustering structure: a biomedical dataset of kidney disease and another dataset of community-level socioeconomic indicators. We benchmarked the Numero subgroupings against popular clustering algorithms (principal components, K-means and hierarchical clustering). The Numero subgroupings were more intuitive and easier to interpret without losing mathematical quality. Therefore, we expect Numero to be useful for exploratory analyses of population-based epidemiological datasets.
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