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   https://doi.org/10.1007/s10107-018-1339-4  

   Bodur, Merve; Luedtke, James R. (October 2018, Mathematical Programming)

   Multi-stage stochastic linear programs (MSLPs) are notoriously hard to solve in general. Linear decision rules (LDRs) yield an approximation of an MSLP by restricting the decisions at each stage to be an affine function of the observed uncertain parameters. Finding an optimal LDR is a static optimization problem that provides an upper bound on the optimal value of the MSLP, and, under certain assumptions, can be formulated as an explicit linear program. Similarly, as proposed by Kuhn et al. (Math Program 130(1):177–209, 2011) a lower bound for an MSLP can be obtained by restricting decisions in the dual of the MSLP to follow an LDR. We propose a new approximation approach for MSLPs, two-stage LDRs. The idea is to require only the state variables in an MSLP to follow an LDR, which is sufficient to obtain an approximation of an MSLP that is a two-stage stochastic linear program (2SLP). We similarly propose to apply LDR only to a subset of the variables in the dual of the MSLP, which yields a 2SLP approximation of the dual that provides a lower bound on the optimal value of the MSLP. Although solving the corresponding 2SLP approximations exactly is intractable in general, we investigate how approximate solution approaches that have been developed for solving 2SLP can be applied to solve these approximation problems, and derive statistical upper and lower bounds on the optimal value of the MSLP. In addition to potentially yielding better policies and bounds, this approach requires many fewer assumptions than are required to obtain an explicit reformulation when using the standard static LDR approach. A computational study on two example problems demonstrates that using a two-stage LDR can yield significantly better primal policies and modestly better dual policies than using policies based on a static LDR. 

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2. Stage-discharge relationship in tidal channels: Tidal stage-discharge relationship

   https://doi.org/10.1002/lom3.10168  

   Kearney, William S.; Mariotti, Giulio; Deegan, Linda A.; Fagherazzi, Sergio (April 2017, Limnology and Oceanography: Methods)
3. How intra-stage and inter-stage competition affect overcompensation in density and hydra effects in single-species, stage-structured models

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   Sorenson, Darian K.; Cortez, Michael H. (March 2021, Theoretical Ecology)

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4. Paleofloods stage a comeback

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   St. George, Scott; Hefner, Amanda M.; Avila, Judith (December 2020, Nature Geoscience)

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5. From Stage to Classroom – the Transfer of Knowledge through the Festival “Science on Stage”

   https://doi.org/10.1557/adv.2017.95  

   Tajmel, Tanja; Salzmann, Ingo (January 2017, MRS Advances)

   ABSTRACT We present an evaluation carried out on a large-scale teacher training activity, the festival “Science on Stage” (SonS) 2013. SonS is a European initiative offering teachers the opportunity to share ideas and teaching practices both on the national and international level. We evaluated the project’s effectiveness in pursuing clear objectives, in clearly defining the target group, and in internationally disseminating teaching projects. Our study documents the transfer of knowledge from the festival to the classroom, aims to identify the prerequisites thereof and, finally, allows formulating key factors for successful future large-scale science communication activities. 

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