0000000000531718
AUTHOR
Jari Hämäläinen
showing 3 related works from this author
An Online Inquiry Tool to Support the Exploration of Controversial Issues on the Internet
2016
This paper describes a theoretically informed Online Inquiry Tool designed to support the exploration of controversial issues on the Internet. The tool’s design is grounded in principles associated with theories of online research and comprehension, argumentation for learning, representational guidance, and cognitive load. The purpose of the tool is to help students organize, monitor, and regulate several complex cognitive activities likely to present challenges during online inquiry. Supports are embedded into the digital tool to help students plan their information search around a controversial issue, identify supporting arguments and counterarguments related to this issue, critically eva…
Hygro-elasto-plastic model for planar orthotropic material
2015
An in-plane elasto-plastic material model and a hygroexpansivity-shrinkage model for paper and board are introduced in this paper. The input parameters for both models are fiber orientation anisotropy and dry solids content. These two models, based on experimental results, could be used in an analytical approach to estimate, for example, plastic strain and shrinkage in simple one-dimensional cases, but for studies of the combined and more complicated effects of hygro-elasto-plastic behavior, a numerical finite element model was constructed. The finite element approach also offered possibilities for studying different structural variations of an orthotropic sheet as well as buckling behavior…
Designing Paper Machine Headbox Using GA
2003
Abstract A non-smooth biobjective optimization problem for designing the shape of a slice channel in a paper machine headbox is described. The conflicting goals defining the optimization problem are the ones determining important quality properties of produced paper: 1) basis weight should be even and 2) the wood fibers of paper should mainly be oriented to the machine direction across the width of the whole paper machine. The novelty of the considered approach is that maximum deviations are used instead of least squares when objective functions are formed. For the solution of this problem, a multiobjective genetic algorithm based on nondominated sorting is considered. The numerical results…