A severity assessment method for multiple voltage sag

2017 ◽  
Author(s):  
Xiangyang Gong ◽  
Yinshu Yu ◽  
Bo Wang ◽  
Fan Ye ◽  
Niancheng Zhou
Keyword(s):  
Assessment Method ◽  
Voltage Sag ◽  
Severity Assessment

Credibility Measure and Assessment Method of Equipment Severity to Voltage Sag

2012 ◽  
Vol 605-607 ◽  
pp. 788-792
Author(s):  
Xu Na Liu ◽  
Ying Wang ◽  
Xian Yong Xiao
Keyword(s):  
Probability Measure ◽  
Assessment Method ◽  
Assessment Model ◽  
Credibility Measure ◽  
Voltage Sag ◽  
Possibility Measure ◽  
Classical Probability ◽  
Fitting Method ◽  
Assessment Measure ◽  
The Status

In order to accurately describe the equipment’ severity caused by voltage sag, the credibility measure which meets the conditions of non-additive is proposed based on their physical properties of responses. This assessment measure can avoid the deficiencies that classical probability measure needs a large number of samples and the non-duality of fuzzy measure. The membership functions of sensitive equipment voltage tolerance capability that corresponding to the characteristic quantities in the status uncertain area was determined by fuzzy statistical method and polynomial fitting method. Then the joint credibility distribution function was deduced based on uncertainty theory. Hence, the assessment model of severity of equipment failure is constructed. Based on practical samples, the PCs were simulated using the proposed method. Comparing the simulation results with methods using classical probability measure and possibility measure prove that the proposed method is proper and credible and can reflect practical condition more objectively.

New Voltage Sag Frequency Evaluation Method Considering the Satisfaction Degree of Sensitive Customer

2012 ◽  
Vol 614-615 ◽  
pp. 1069-1074
Author(s):  
Jun He ◽  
Xu Na Liu ◽  
Li Ping Chen
Keyword(s):  
Evaluation Method ◽  
Engineering Application ◽  
Assessment Method ◽  
Voltage Sag ◽  
Testing System ◽  
Satisfaction Degree ◽  
Practical Engineering ◽  
The Relationship ◽  
Customer Satisfaction Degree ◽  
Critical Fault

To meet power customers’ satisfaction is the essential responsibilities of utilities. Considering the property of customer’s satisfaction degree, an analytical interval assessment method of voltage sag is proposed. The customer satisfaction degree is presented by interval number corresponding to the voltage tolerance for the tested equipment installed at the customer side. Based on the determination function derived from the relationship between the voltage magnitude and the length of fault line in the power system, critical fault positions are determined through analytical iterative algorithm. By the variation of satisfaction degree within a given interval, the interval sag frequency is calculated. Moreover, the quantitative sag frequency is determined by the help of the interval sag frequency. The proposed method is applied to a five-bus system and IEEE 30-bus testing system. The simulation results comparing with existing methods have shown that this method is credible and suitable for the practical engineering application.

scholarly journals Severity assessment in the Nicotiana tabacum-Xylella fastidiosa subsp. pauca pathosystem: design and inter-laboratory validation of a standard area diagram

2020 ◽  
Author(s):  
Willian Eduardo Lino Pereira ◽  
Sheila Andrade ◽  
Emerson Medeiros Del Ponte ◽  
Mariana Bossi Esteves ◽  
Maria Cristina Canale ◽  
...  
Keyword(s):  
Nicotiana Tabacum ◽  
Xylella Fastidiosa ◽  
Assessment Method ◽  
Ordinal Scale ◽  
Severity Assessment ◽  
Plant Host ◽  
Perfect Agreement ◽  
Accuracy And Precision ◽  
Percent Area ◽  
True Color

Nicotiana tabacum, a non-natural host, is an excellent plant model for biological and functional genomics studies on plant host-Xylella fastidiosa interactions. Symptoms by X. fastidiosa subsp. pauca on tobacco have been characterized but current severity assessment method is an ordinal scale developed for symptoms on citrus. We designed a standard area diagram (SAD) to aid in the visual estimation of percent area affected (% severity) and performed a multi-laboratory validation on tobacco cv. 'Havana inoculated with X. fastidiosa subsp. pauca. Inoculated plants were monitored over time and digital images of the symptoms were obtained. Three different softwares (APS Asses, ImageJ and Leaf Doctor) were used to segment the images and calculate % severity. Ten true-color images composed a 10-image SAD (0.5, 5, 10, 15, 25, 35, 45, 55, 65 and 75%). Fifty raters at four laboratories assigned % severity first without and then with the SAD on the same testing image set of 40 images following the same instructions provided by an examiner at each Laboratory. The means of % severity by all softwares were assumed to represent the actual % severity given the perfect agreement between them. The unaided estimates were less precise, biased towards overestimation (up to 50 percent points) and less concordant between raters. Accuracy and precision varied considerably among the raters and effect of the SAD on the overall concordance to the actual severity was dependent on the Laboratory; in all but one Laboratory, the group means of the agreement index statistically improved. The between-rater agreement improved in all Laboratories when using the SAD. The SAD may help to standardize and allow comparison across different laboratories, but care should be taken during instructions on how to discriminate symptoms that are not readily discernible as well as on how to correctly use of the SAD.

Delir-Diagnostik

2007 ◽  
Vol 20 (2-3) ◽  
pp. 135-139
Author(s):  
B. Dittrich ◽  
G. Gatterer ◽  
T. Frühwald ◽  
U. Sommeregger
Keyword(s):  
Confusion Assessment Method ◽  
Assessment Method ◽  
Psychische Störung ◽  
Confusion Assessment

Zusammenfassung: Das Delir (“akuter Verwirrtheitszustand”) bezeichnet eine psychische Störung, die plötzlich auftritt, durch eine rasche Fluktuation von Bewusstseinslage und Aufmerksamkeitsleistung gekennzeichnet ist und eine organische Ursache hat. Dieses Störungsbild nimmt bei Patienten im höheren Lebensalter deutlich an Häufigkeit zu und verursacht durch verlängerte Krankenhausaufenthalte und ungünstige Krankheitsverläufe erhebliche Kosten im Gesundheitssystem. Daher erscheint eine möglichst frühe Erkennung deliranter Zustandsbilder gerade im Rahmen der Geriatrie von großer Bedeutung. Zu diesem Zweck wurde eine deutsche Version der international weit verbreiteten Confusion Assessment Method entwickelt, die für die Bedürfnisse einer Abteilung für Akutgeriatrie modifiziert wurde. Dargestellt werden die Entwicklung und erste Erfahrungen mit diesem Instrument.

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