Expert control of DO in the aerobic reactor of an activated sludge process

Abstract An expert control structure is proposed for the control of dissolved oxygen (DO) in a Nitrification Denitrification Biological Excess Phosphorus Removal (NDBEPR) plant to account for the several processes that are influenced by the DO concentration in the aerator. In the scheme a supervisory fuzzy controller determines the set point of an inner DO control loop where an Adaptive Robust Generic Model Control (ARGMC) controller is used. The fuzzy supervisory control has a hierarchical structure. Off-line measurements of biological parameters of influent and effluent streams can be used to periodically update the set points of the fuzzy controllers. The complete control scheme has been…

Hepatitis C virus (HCV) infection in elderly patients: A multicenter Italian cross-sectional study

Add-on peginterferon alfa-2a to nucleos(t)ide analogue therapy for Caucasian patients with hepatitis B ‘e’ antigen-negative chronic hepatitis B genotype D

Nucleos(t)ide analogues (NAs) and peginterferon have complementary effects in chronic hepatitis B, but it is unclear whether combination therapy improves responses in genotype D-infected patients. We conducted an open-label study of peginterferon alfa-2a 180 μg/week added to ongoing NA therapy in hepatitis B e antigen (HBeAg)-negative, genotype D-infected patients with HBV DNA <20 IU/mL. The primary endpoint was proportion of patients with ≥50% decline in serum HBsAg by the end of the 48-week add-on phase. Seventy patients received treatment, 11 were withdrawn at week 24 for no decrease in HBsAg, and 14 withdrew for other reasons. Response rate (per-protocol population) was 67.4% (29/43) at…

Integration of interlock system analysis with automated HAZOP analysis

Abstract The paper details the integration of a method for the analysis of interlock systems with a software support system for HAZOP analysis. The proposed software aims to enhance the potential of HAZOP in terms of depth and efficiency of the analysis. This enhancement is reached through the continuation of the hazard and operability analysis, limited to a group of events which may hold high risks for the plant and/or surrounding environment. The analysis technique of the emergency interlock systems and other plant protection measures proposed by the Center for Chemical Process Safety (CCPS) of the American Institution of Chemical Engineers (AIChE) has been assumed as a starting point. Th…

Qualitative models of equipment units and their use in automatic HAZOP analysis

Abstract The use of qualitative models in a support system for HAZOP analyses, in connection with an algorithm for finding the causes and the consequences of variable deviations, is described. The models use several representation structures among which mini-trees constitute the most important from the logical-functional point of view. The models are conceived both for continuous and batch plants. For the latter procedures, regulating the use of equipment units are also modelled using similar structures while equipment units are considered in various phases of their functioning. A brief description of the prototype support system, in which the models are implemented, is also given.

Undetectable HCV-RNA at treatment-week 8 results in high-sustained virological response in HCV G1 treatment-experienced patients with advanced liver disease: The International Italian/Spanish Boceprevir/Peginterferon/Ribavirin Name Patients Program

In many countries, first-generation protease inhibitors (PIs)/peginterferon/ribavirin (P/R) still represent the only treatment option for HCV-infected patients. Subjects with advanced disease and previous failure to P/R urgently need therapy, but they are under-represented in clinical trials. All treatment-experienced F3/4 Metavir patients who received boceprevir (BOC)+P/R in the Italian-Spanish Name Patient Program have been included in this study. Multivariate logistic regression analysis (MLR) was used to identify baseline and on-treatment predictors of SVR and adverse events (AEs). Four hundred and sixteen patients, mean age 57.7 (range 25-78 years), 70% males, 69.5% (289/416) F4, 14% (…

Corrigendum to ‘An international genome-wide meta-analysis of primary biliary cholangitis: Novel risk loci and candidate drugs’ [J Hepatol 2021;75(3):572–581] (Journal of Hepatology (2021) 75(3) (572–581), (S0168827821003342), (10.1016/j.jhep.2021.04.055))

It has come to our attention that the name of one of the authors in our manuscript was incorrectly spelled ‘Jinyoung Byan’; the correct spelling is ‘Jinyoung Byun’ as in the author list above. In addition, the excel files of the supplementary tables were not included during the online publication of our article. These have now been made available online. We apologize for any inconvenience caused.

A Laboratory Project for Advanced Control Methods: Control of a Neutralization Process

Abstract A neutralization process is used in a laboratory project for experimenting advanced control techniques. Students may choose among several techniques to experience the behaviour of advanced controller action: adaptive control, GMG control, fuzzy control, self tuning fuzzy control, neural control, neuro-fuzzy control. The experience in advanced self tuning controller based on fuzzy logic is proposed for the control of a neutralization process. The test of a self tuning controller based on fuzzy logic is a very important case because the resulting structure of the controller is easy to implement and modify: the final results are compared with those deriving from the application of a c…

Carbon nanotubes embedded in a polyimide foil for proton acceleration with a sub-ns laser

A series of thin films made of aligned carbon nanotubes (CNTs) embedded in a polyimide substrate was designed, fabricated and used for the first time to accelerate protons and C ions by interaction with a sub-nanosecond, high power laser beam (600 J energy and 300 ps pulse width) with peak intensity of about 3 × 1016 W/cm2 on target. Each target was 5 μm thick, and the composite material contained CNTs aligned in different directions in the substrate. The results obtained from the analysis of a Thomson Parabola spectrometer, and of the spots imprinted by ions on a series of PM355 nuclear track detectors, indicate high energies (up to 3 MeV for protons and 9 MeV for C ions) and a marked infl…

Expert control of DO in the aerobic reactor of an activated sludge process

Abstract An expert control structure is proposed for the control of dissolved oxygen (DO) in a Nitrification Denitrification Biological Excess Phosphorus Removal (NDBEPR) plant to account for the several processes that are influenced by the DO concentration in the aerator. In the scheme a supervisory fuzzy controller determines the set point of an inner DO control loop where an Adaptive Robust Generic Model Control (ARGMC) controller is used. The fuzzy supervisory control has a hierarchical structure. Off-line measurements of biological parameters of influent and effluent streams can be used to periodically update the set points of the fuzzy controllers. The complete control scheme has been…

Adaptive Fuzzy Control of a Process with Bifurcations

Several fuzzy controllers with different structures have been considered for the control of systems with bifurcation. A mixed feedforward-feedback structure with some additional adaptation mechanisms have been checked by simulation in the control of a non-linear process constituted by a bubble column in which a slow kinetics auto-catalytic reaction takes place. Simulation results show the validity of some of the proposed controllers in avoiding the system reaching bifurcation and instability conditions.