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Automatic generation control is extensively used to regulate power plants in a modern area of the power system network. In this paper, automatic generation and frequency control in interconnected power system is presented. A multisource such as thermal, hydro, and gas-based power plant is considered in this study, which is carried out by incorporating nonlinearity like generation rate constants, HVDC link, and the conventional PID controller design. Further, an optimal setting of the PID controller is performed by employing evolutionary, and metaheuristic algorithm-based approaches such as differential evolution and firefly algorithm, respectively. With these algorithms, the proposed model has been tested with their performance evaluation and comparison characteristics are discoursed. The robustness of the proposed controllers is assessed based on comparative analyses to regulate the interconnected power network's frequency profile under different loading conditions. The stability analysis is performed using the Eigen and Nyquist plots to assess the proposed controllers' efficacy. Besides, the frequency control study is summarized with comparative assessment through various performance indices such as settling time, peak overshoot and undershoots under different operating conditions. Finally, the proposed control scheme, in the interconnected power system, is validated through a real-time digital simulation platform, i.e., OPAL-RT 5142. The comparison of simulation and real-time results demonstrates the effectiveness of the FA-optimized PID controller in comparison with that of the DE-optimized PID controller. [ABSTRACT FROM AUTHOR]

Background: Regorafenib has been approved among the treatment options for patients with advanced stage colorectal cancer (CRC), hepatocellular carcinoma (HCC), and gastrointestinal stromal tumors (GIST). In this study, we aim to report the real-life experience of the safety and tolerability regorafenib in our institution. Methods: We conducted a retrospective chart review of 43 patients who received regorafenib in Kuwait Cancer Control Center (KCCC) from 2016 to the end of 2019. Data collected include diagnosis, patient demographics, performance status, number of previous lines of treatment, number of treatment cycles, side effects, best-tolerated dose, and treatment discontinuation due to intolerability. Univariate analysis with Pearson chi-square test were conducted to study co-relation between discontinuation rates and several factors. Results: We had available data for 43 patients (23 males and 20 females). Of the patients, 83.7% had an ECOG performance status of 0 or 1. Seventy-three percent were diagnosed with metastatic CRC, 21% were diagnosed with HCC and 6% were diagnosed with GIST tumors. Half of the patients received 3 lines or more of treatment prior to regorafenib. The median number of cycles received was 3.7 with 11.6% of patients still on active treatment at the time of analysis. The most reported grade 3 and above side effects included rash (41.9%), fatigue (39.6 %), hypertension (25.6%), mucositis (21.9%), hand-foot syndrome (2.3%), and hyperbilirubinemia (4.6%). The best-tolerated dose was 80 mg and that was achieved in 44.2% of patients. The recommended dose of 160 mg could only be achieved in 20.9% of patients. The treatment was discontinued because of intolerability in 25.6% of patients. The discontinuation rates in those with ages 60 years and above versus below 60 years were 91% and 68%, respectively. Conclusion: In our cohort, the best-tolerated dose of regorafenib was 80 mg. Toxicity and intolerability of regorafenib lead to treatment discontinuation in nearly a quarter of patients. Patient age may influence tolerance and adherence to regorafenib. [ABSTRACT FROM AUTHOR]

In this paper, a multilevel inverter based shunt hybrid active filter is used, which is composed of passive filter and shunt active filter, used for enhancing the quality of power, by reducing the total harmonic distortions below 5% as per IEEE-519 standard and managing the reactive power as well as correcting the power factor. The objective of this paper is to advance the power quality by reducing the harmonic distortions in the distribution line, which are affected because of utilising non-linear loads across the load end. For reference current generation and for controlling the switching signal, conventionally PI controller was used with different reference signal detection techniques. But with the evolution of different intelligence approaches, made more advantageous than the PI controller. In this paper, two artificial intelligence methods, i.e, artificial neural network and adaptive neuro-fuzzy interference system (ANFIS) are applied. Comparison of the results of the proposed methods is analysed using MATLAB/ SIMULINK tool. For reference current generation, synchronous reference frame theory is used and hysteresis current control technique is employed for generating the gating signal. [ABSTRACT FROM AUTHOR]

A novel switching pulse generation methodology based on adaptive fuzzy hysteresis current controlled hybrid shunt active power filter (A-F-HCC-HSAPF) is presented in this paper for compensating reactive power and harmonics in distribution network. The harmonic problems are mainly evolved because of extensive use of nonlinear loads in industry and domestic sectors. There are some adverse effects of harmonics such as: malfunctioning of sensitive equipment, resonance issues, conductors heating, power losses and reduced efficiency in distribution system. To mitigate harmonics issues passive, filters are used but when the harmonic component increases the design of passive filters is complex and becomes bulky. With the advancement in power electronic, the active power filter has been designed. Generally, the rating of the active filter is very high for some applications; hence hybrid shunt active power filter (HSAPF) is proposed by low-rated shunt active power filter (SAPF) and low-cost shunt passive filter. Proportional-integral or fuzzy logic controller is used to estimate the reference current and to regulate the dc capacitor voltage. To generate the switching pulse for the voltage source inverter of the SAPF, a novel adaptive fuzzy hysteresis current controller (A-F-HCC) is adopted. The performance of the proposed A-F-HCC-HSAPF is investigated during steady-state and transient conditions using MATLAB/Simulink and real-time environments. [ABSTRACT FROM AUTHOR]