Plan B: Uncertainty/Time Trade-Offs for Linear and Integer Programming

A test of knowledge-based forest operations scheduling procedures

Canadian Journal of Forest Research ◽

10.1139/x26-133 ◽

1996 ◽

Vol 26 (7) ◽

pp. 1193-1202 ◽

Cited By ~ 4

Author(s):

Cristopher L. Brack ◽

Peter L. Marshall

Keyword(s):

Linear Programming ◽

Integer Programming ◽

Mathematical Programming ◽

Expert Systems ◽

Mixed Integer Programming ◽

Mixed Integer ◽

Forest Operations ◽

Knowledge Based ◽

Operations Scheduling ◽

Trade Offs

Five knowledge-based approaches (three search routines and two expert systems) to forest operations scheduling were compared with mathematical programming (linear programming and mixed integer programming) and simulation approaches for two plantation forests in New South Wales, Australia. Strategies produced using these approaches were compared on the basis of scores for timber volume flow, scenic beauty, stand health, and water quality. Timber flow scores were highest for the linear programming strategies, but some of the strategies produced by the knowledge-based approaches scored almost as high. The timber flow scores for the mixed integer programming strategies were exceeded by some of the knowledge-based strategies, because of the approximations required to achieve mixed integer programming solutions for larger problems. The knowledge-based approaches could produce higher scoring strategies for the other criteria than the mathematical programming or simulation approaches. The multiple strategies produced by two of the search procedures, and the goal hierarchy incorporated into the expert systems, allow the user to make explicit trade-offs among strategies in terms of performance for the various criteria.

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Novel players fine-tune plant trade-offs

Essays in Biochemistry ◽

10.1042/bse0580083 ◽

2015 ◽

Vol 58 ◽

pp. 83-100 ◽

Cited By ~ 25

Author(s):

Selena Gimenez-Ibanez ◽

Marta Boter ◽

Roberto Solano

Keyword(s):

Ubiquitin Ligase ◽

Feedback Loop ◽

Molecular Level ◽

26S Proteasome ◽

Signalling Molecules ◽

Transcriptional Reprogramming ◽

Trade Offs ◽

Jaz Proteins ◽

Regulatory Feedback Loop ◽

Fine Tune

Jasmonates (JAs) are essential signalling molecules that co-ordinate the plant response to biotic and abiotic challenges, as well as co-ordinating several developmental processes. Huge progress has been made over the last decade in understanding the components and mechanisms that govern JA perception and signalling. The bioactive form of the hormone, (+)-7-iso-jasmonyl-l-isoleucine (JA-Ile), is perceived by the COI1–JAZ co-receptor complex. JASMONATE ZIM DOMAIN (JAZ) proteins also act as direct repressors of transcriptional activators such as MYC2. In the emerging picture of JA-Ile perception and signalling, COI1 operates as an E3 ubiquitin ligase that upon binding of JA-Ile targets JAZ repressors for degradation by the 26S proteasome, thereby derepressing transcription factors such as MYC2, which in turn activate JA-Ile-dependent transcriptional reprogramming. It is noteworthy that MYCs and different spliced variants of the JAZ proteins are involved in a negative regulatory feedback loop, which suggests a model that rapidly turns the transcriptional JA-Ile responses on and off and thereby avoids a detrimental overactivation of the pathway. This chapter highlights the most recent advances in our understanding of JA-Ile signalling, focusing on the latest repertoire of new targets of JAZ proteins to control different sets of JA-Ile-mediated responses, novel mechanisms of negative regulation of JA-Ile signalling, and hormonal cross-talk at the molecular level that ultimately determines plant adaptability and survival.

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Immediate Access to Plan B Didn't Increase Use

Internal Medicine News ◽

10.1016/s1097-8690(08)70849-7 ◽

2008 ◽

Vol 41 (15) ◽

pp. 28

Author(s):

SHERRY BOSCHERT

Keyword(s):

Plan B

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Dual Goals for Speed and Accuracy on the Same Performance Task

Journal of Personnel Psychology ◽

10.1027/1866-5888/a000063 ◽

2012 ◽

Vol 11 (3) ◽

pp. 118-126 ◽

Cited By ~ 3

Author(s):

Olive Emil Wetter ◽

Jürgen Wegge ◽

Klaus Jonas ◽

Klaus-Helmut Schmidt

Keyword(s):

Memory Scanning ◽

Performance Task ◽

Performance Tasks ◽

Trade Off ◽

Test Experiment ◽

Trade Offs ◽

New Finding ◽

Sternberg Paradigm ◽

Speed Accuracy ◽

Speed And Accuracy

In most work contexts, several performance goals coexist, and conflicts between them and trade-offs can occur. Our paper is the first to contrast a dual goal for speed and accuracy with a single goal for speed on the same task. The Sternberg paradigm (Experiment 1, n = 57) and the d2 test (Experiment 2, n = 19) were used as performance tasks. Speed measures and errors revealed in both experiments that dual as well as single goals increase performance by enhancing memory scanning. However, the single speed goal triggered a speed-accuracy trade-off, favoring speed over accuracy, whereas this was not the case with the dual goal. In difficult trials, dual goals slowed down scanning processes again so that errors could be prevented. This new finding is particularly relevant for security domains, where both aspects have to be managed simultaneously.

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