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Discussion is presented of historical developments of blast furnace modelling from the 1960s to the present day. The models are broadly classified into comprehensive, zone-specific, and data-driven models. The comprehensive models are further classified into lumped models, 1-D, 2-D and 3-D steady state and transient models, and CFD-DEM models. The zone-specific models are exemplified by burden distribution models only. The data-driven models correspond to black-box models based solely on operation data to estimate or predict the key performance index. It is concluded that first-principle models and data-driven methods all serve clear and different purposes. With an increase in computational capabilities offered by cloud computing and the advancement of graphics processing technology, as well as developments in artificial intelligence algorithms, it is possible to develop both better data-driven models and hybrid systems which combine both model types., Discussion is presented of historical developments of blast furnace modelling from the 1960s to the present day. The models are broadly classified into comprehensive, zone-specific, and data-driven models. The comprehensive models are further classified into lumped models, 1-D, 2-D and 3-D steady state and transient models, and CFD-DEM models. The zone-specific models are exemplified by burden distribution models only. The data-driven models correspond to black-box models based solely on operation data to estimate or predict the key performance index. It is concluded that first-principle models and data-driven methods all serve clear and different purposes. With an increase in computational capabilities offered by cloud computing and the advancement of graphics processing technology, as well as developments in artificial intelligence algorithms, it is possible to develop both better data-driven models and hybrid systems which combine both model types.

Item does not contain fulltext, The American Academy of Pediatrics recently released its new Technical Report and Policy Statement on male circumcision, concluding that current evidence indicates that the health benefits of newborn male circumcision outweigh the risks. The technical report is based on the scrutiny of a large number of complex scientific articles. Therefore, while striving for objectivity, the conclusions drawn by the 8 task force members reflect what these individual physicians perceived as trustworthy evidence. Seen from the outside, cultural bias reflecting the normality of nontherapeutic male circumcision in the United States seems obvious, and the report's conclusions are different from those reached by physicians in other parts of the Western world, including Europe, Canada, and Australia. In this commentary, a different view is presented by non-US-based physicians and representatives of general medical associations and societies for pediatrics, pediatric surgery, and pediatric urology in Northern Europe. To these authors, only 1 of the arguments put forward by the American Academy of Pediatrics has some theoretical relevance in relation to infant male circumcision; namely, the possible protection against urinary tract infections in infant boys, which can easily be treated with antibiotics without tissue loss. The other claimed health benefits, including protection against HIV/AIDS, genital herpes, genital warts, and penile cancer, are questionable, weak, and likely to have little public health relevance in a Western context, and they do not represent compelling reasons for surgery before boys are old enough to decide for themselves.

The role is discussed of burden distribution in the control of the blast furnace due to its effect on the gas distribution and the chemical and thermal efficiency of the dry part of the shaft, and on the shape and level of the cohesive zone. A method is described in which a genetic algorithm is used to automatically generate new charging strategies. A simplified mathematical model of the burden distribution in a bell-top furnace is used to evaluate the strategies. The differences between the desired and calculated radial distributions of ore (sinter and pellets) and coke are minimised subject to charging constraints such as movable armor settings and skip size., The role is discussed of burden distribution in the control of the blast furnace due to its effect on the gas distribution and the chemical and thermal efficiency of the dry part of the shaft, and on the shape and level of the cohesive zone. A method is described in which a genetic algorithm is used to automatically generate new charging strategies. A simplified mathematical model of the burden distribution in a bell-top furnace is used to evaluate the strategies. The differences between the desired and calculated radial distributions of ore (sinter and pellets) and coke are minimised subject to charging constraints such as movable armor settings and skip size.