4 research outputs found
Cross-Domain Reuse of Extracted Knowledge in Genetic Programming for Image Classification
© 2017 IEEE. Genetic programming (GP) is a well-known evolutionary computation technique, which has been successfully used to solve various problems, such as optimization, image analysis, and classification. Transfer learning is a type of machine learning approach that can be used to solve complex tasks. Transfer learning has been introduced to GP to solve complex Boolean and symbolic regression problems with some promise. However, the use of transfer learning with GP has not been investigated to address complex image classification tasks with noise and rotations, where GP cannot achieve satisfactory performance, but GP with transfer learning may improve the performance. In this paper, we propose a novel approach based on transfer learning and GP to solve complex image classification problems by extracting and reusing blocks of knowledge/information, which are automatically discovered from similar as well as different image classification tasks during the evolutionary process. The proposed approach is evaluated on three texture data sets and three office data sets of image classification benchmarks, and achieves better classification performance than the state-of-the-art image classification algorithm. Further analysis on the evolved solutions/trees shows that the proposed approach with transfer learning can successfully discover and reuse knowledge/information extracted from similar or different problems to improve its performance on complex image classification problems
Multicriteria decision making for resource management in renewable energy assisted microgrids
Microgrids assisted by renewable energy resources are complex man made systems of various interconnected components. A number of real life scenarios relating to resource management in microgrids are modeled as multi-objective optimization formulations where multiple objectives may or may not conflict with each other. While considering the type of application, input and output of the problem, the nature of optimization problem changes. To address various types of optimization problems relating to microgid design, planning and operation, there exist a number of optimization solution types. We investigate the existing literature to classify different optimization objectives with respect to designing, planning and operation of microgrids. Some mathematical formulations for commonly used objectives relating to resource management in microgrids have been tabulated. We also classified the optimization types being used to address various optimization problems relating to resource management in microgrids. Various types of solution approaches along with the relevant simulation tools are also presented. We also reviewed the multicriteria optimization for different application areas of smart grid. The article can serve as a foundation for further research in the area of multicriteria decision making relating to resource management in micrgorids
Cellular mechanisms in higher plants governing tolerance to cadmium toxicity
Cadmium (Cd) is an inorganic mineral in the earth’s crust. Cadmium entry into the environment occurs through geogenic and anthropogenic sources. Industrial activities including mining, electroplating, iron and steel plants, and battery production employ Cd during their processes and often release Cd into the environment. When disseminated into soil, Cd can be detrimental to agroecosystems because it is relatively mobile and phytotoxic even at low concentrations. Cadmium’s phytotoxicity is due to reductions in the rate of transpiration and photosynthesis and chlorophyll concentration resulting in retardation of plant growth, and an alteration in the nutrient concentration in roots and leaves. In responseto Cd toxicity, plants have developed protective cellular mechanisms such as synthesis of phytochelatins and metallothioneins, metal compartmentalization in vacuoles, and the increased activity of antioxidant enzymes to neutralize Cd-induced toxicity. While these direct protective mechanisms can help alleviate Cd toxicity, other indirect mechanisms such as microelements (zinc, iron, manganese, and selenium) interfering with Cd uptake may decrease Cdconcentration in plants. This comprehensive review encompasses the significance of Cd, portals of contamination and toxicity to plants, and implications for crop production. Various mitigation strategies with the beneficial effects of zinc, iron, manganese, andselenium in activating defence mechanisms against Cd stress are discussed. Furthermore, this review systematically identifies and summarises suitable strategies for mitigating Cd-induced toxicityin plants
Longitudinal immune profiling reveals key myeloid signatures associated with COVID-19
COVID-19 pathogenesis is associated with an exaggerated immune response. However, the specific cellular mediators and inflammatory components driving diverse clinical disease outcomes remain poorly understood. We undertook longitudinal immune profiling on both whole blood and peripheral blood mononuclear cells of hospitalized patients during the peak of the COVID-19 pandemic in the United Kingdom. Here, we report key immune signatures present shortly after hospital admission that were associated with the severity of COVID-19. Immune signatures were related to shifts in neutrophil to T cell ratio, elevated serum IL-6, MCP-1, and IP-10 and modulation of CD14+ monocyte phenotype and function. Modified features of CD14+ monocytes included poor induction of the prostaglandin-producing enzyme, COX-2, and enhanced expression of the cell cycle marker Ki-67. Longitudinal analysis revealed reversion of some immune features back to the healthy median level in patients with a good eventual outcome. These findings identify previously unappreciated alterations in the innate immune compartment of patients with COVID-19 and lend support to the idea that therapeutic strategies targeting release of myeloid cells from bone marrow should be considered in this disease. Moreover, they demonstrate that features of an exaggerated immune response are present early after hospital admission, suggesting that immunomodulating therapies would be most beneficial at early time points