Mohsen Tajdinian, Shahram Montaser Kouhsari, Kazem Mohseni and Mehdi Zareian Jahromi
Decaying DC component has important effect on extracting the fundamental component phasor. It directly affects the precision of protective relaying algorithms which act based on…
Abstract
Purpose
Decaying DC component has important effect on extracting the fundamental component phasor. It directly affects the precision of protective relaying algorithms which act based on fundamental frequency component. It can be noted that decaying DC component, harmonic components and off-nominal frequency conditions are the major issues which strongly effect phasor estimation. The paper aims to discuss these issues.
Design/methodology/approach
This paper proposes a novel hybrid approach for fundamental phasor estimation in order to remove the decaying DC component using Hilbert Transform and Discrete Fourier Transform.
Findings
The proposed method (PM) converges to the original value in one cycle in presence of harmonic components and off-nominal frequency condition. In addition, proposed algorithm is able to detect the frequency fluctuation. Thus, it is applicable for static and dynamic conditions. An extensive set of simulation results across static and dynamic validations demonstrated that the proposed approach has faster convergence and better precision than the present methods. In addition, during harmonic distortion and also frequency fluctuation, the PM provides a correct and reliable response.
Originality/value
The PM can calculate the DC component exactly from fault current signals and can be used in digital protection algorithms for phasor estimation.
Details
Keywords
Shirin Amini, Houra Mohseni, Behnaz Abiri and Sima Jafarirad
Depression is one of the most overlooked psychiatric disorders among middle-aged and elderly men. Saffron (Crocus sativus L.) stigmas are a favorite and common spice that is used…
Abstract
Purpose
Depression is one of the most overlooked psychiatric disorders among middle-aged and elderly men. Saffron (Crocus sativus L.) stigmas are a favorite and common spice that is used as an antidepressant, an anti-inflammatory and a sexual stimulant. This systematic review aimed to provide a comprehensive survey of the effects of saffron on depression in middle-aged and elderly men.
Design/methodology/approach
The authors searched Web of Science, PubMed, ProQuest, Cochrane, Science Direct, Scopus and Google Scholar databases to gather any relevant studies published from 1980 to September 2022. This review included studies that examined the relationship between depression and testosterone concentration (four studies) or saffron’s effects on testosterone and depression (six studies).
Findings
Observational research showed an association between testosterone and depression in middle-aged and elderly men. Furthermore, animal studies have found that saffron increased testosterone levels and decreased depression in males. There is evidence that testosterone may contribute to the mood. Besides its antioxidant and anti-inflammatory properties, this study proposed scientific mechanisms that saffron may also play a protective role against depression through its influence on testosterone, in middle-aged and elderly men. The general use of saffron at high doses or for prolonged periods may cause side effects; therefore, it is important to consult a health-care professional before the recommended dosage and duration of saffron supplementation, especially if a person has any underlying health conditions or is taking medications.
Originality/value
This study provides researchers with an additional perspective for conducting clinical trials on the use of saffron to enhance the mood of elderly men with testosterone deficiency.