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Microalgae, as photosynthetic organisms, are cultivated in photobioreactors for various industrial applications. Light intensity, a critical factor influencing their growth rate, is inherently nonuniform within photobioreactors. In regions distant from the illuminated surface, microalgae experience photolimitation due to insufficient photon availability, hindering optimal activation of the photosy
Modeling the evolution process for the growth of microalgae in an artificial pond is a huge challenge given the complex interaction between hydrodynamics and biological processes occurring across various timescales. In this paper, we consider a raceway, i.e., an oval pond where the water is set in motion by a paddle wheel. Our aim is to investigate theoretically and numerically the impact of botto
From the Wunderkammern of Renaissance Europe to the curated vaults of today’s natural history museums, millions of insect specimens have been preserved, capturing an irreplaceable chronicle of biodiversity, including lineages that are rare, highly specialized, or already extinct. Yet their fragility has historically constrained genomic inquiry. Here, we apply museomic methodology to a >40-year-old
We propose to use Neumann–Neumann algorithms for the time parallel solution of unconstrained linear parabolic optimal control problems. We study nine variants, analyze their convergence behavior, and determine the optimal relaxation parameter for each. Our findings indicate that while the most intuitive Neumann–Neumann algorithms act as effective smoothers, there are more efficient Neumann–Neumann
We present new Dirichlet–Neumann and Neumann–Dirichlet algorithms with a time domain decomposition applied to unconstrained parabolic optimal control problems. After a spatial semidiscretization, we use the Lagrange multiplier approach to derive a coupled forward-backward optimality system, which can then be solved using a time domain decomposition. Due to the forward-backward structure of the opt
Dynamic light regimes strongly impact microalgal photosynthesis efficiency. Finding the optimal way to supply light is then a tricky problem, especially when the growth rate is inhibited by overexposition to light and, at the same time, there is a lack of light in the deepest part of the culture. In this paper, we use the Han model to study the theoretical microalgal growth rate by applying period
In this article, we focus on a periodic resource allocation problem applied on a dynamical system which comes from a biological system. More precisely, we consider a system with 𝑁 resources and 𝑁 activities, each activity use the allocated resource to evolve up to a given time 𝑇 > 0 where a control (represented by a given permutation) will be applied on the system to reallocate the resources. T
The potential of industrial applications for microalgae has motivated their recent fast development. Their growth dynamics depends on different factors that must be optimized. Since they get their energy from photosynthesis, light is a key factor that strongly influences their productivity. Light is absorbed and scattered in the liquid medium, and irradiance exponentially decreases towards the dar
This paper focuses on mixing strategies and designing shape of the bottom topographies to enhance the growth of the microalgae in raceway ponds. A physical-biological coupled model is used to describe the growth of the algae. A simple model of a mixing device such as a paddle wheel is also considered. The complete process model was then included in an optimization problem associated with the maxim
This paper focuses on mixing strategies to enhance the growth of microalgae in a raceway pond. The flow is assumed to be laminar and the Han model describing the dynamics of the photosystems is used as a basis to determine growth rate as a function of light history. A device controlling the mixing is assumed, which means that the order of the cells along the different layers can be rearranged at e
We present a coupled model describing growth of microalgae in a raceway cultivation process, accounting for hydrodynamics. Our approach combines a biological model (based on the Han model) and shallow water dynamics equations that model the fluid into the raceway. We then describe an optimization procedure dealing with the topography to maximize the biomass production over one lap of the raceway.
How does coalition participation influence party membership? We argue that parties that take part in coalition governments are likely to experience less favorable party membership developments than parties governing alone because of the compromises they have to agree on in multi-party cabinets. This should be particularly likely for parties in ideologically diverse coalition governments since part
Alzheimer’s disease (AD) continues to pose a major global health challenge, with incidence rising sharply and current therapies offering only symptomatic relief. This study builds on prior work into six structurally diverse multi-target compounds (1–6) designed to modulate key pathological processes in AD. We have now combined experimental and computational approaches to determine a set of pharmac
Control of crystallographic texture is key to improving the properties of piezoelectric ceramics, but it has so far mainly been realized in the form of fiber textures perpendicular to the dominant surface of simple 2.5D structures. This work demonstrates how grains in piezoelectric ceramics can be aligned in complex patterns and shapes via material extrusion-based additive manufacturing, specifica
