Improvement of saidi and saifi reliability indices using a shunt circuit-breaker in ungrounded MV networks

2013 ◽  
Author(s):  
M. Gonzalez
Keyword(s):  
Circuit Breaker ◽  
Reliability Indices ◽  
Shunt Circuit

scholarly journals Reliability Evaluation for Cyber-Physical Smart Substation

Complexity ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Yangrong Chen ◽  
Jun’e Li ◽  
Ang Xu ◽  
Kai Yuan ◽  
Kaipei Liu
Keyword(s):  
Smart Grid ◽  
Hybrid Method ◽  
Sampling Method ◽  
Circuit Breaker ◽  
Latin Hypercube Sampling ◽  
Reliability Evaluation ◽  
Stable Operation ◽  
Reliability Indices ◽  
Physical Interactions ◽  
Smart Substation

Smart substation is the key part of smart grid. The reliability of smart substation is extremely important to the safe and stable operation of the smart grid. Smart substation is a cyber-physical system (CPS). Hence, this paper conducts reliability evaluation study for smart substation from the perspective of CPS. Firstly, the basic reliability indices of cyber and physical elements of smart substation are presented. The reliability index of one cyber element takes into account the reliability factors of data leakage, tampering, loss and delay, etc., on the cyber side. Then, the cyber-physical interactions of smart substation are analyzed. It is concluded that the effect of the cyber side and cyber-physical interactions on the reliability of smart substation is reflected in the effect of measurement and control messages on circuit breaker operation. And, the new reliability indices considering cyber-physical interactions are proposed. Furthermore, the MALI-hybrid method, which combines the Monte Carlo method, analytical method, Latin hypercube sampling method, and important sampling method, is presented for evaluating the reliability of smart substation. Finally, the rationality of the proposed reliability indices, the efficiency, and correctness of MALI-hybrid method are verified by case studies.

The influence of switching actions with redundant components on the main reliability substations

2019 ◽  
Vol XXII (2) ◽  
pp. 284-295
Author(s):  
Pană L.
Keyword(s):  
Reliability Analysis ◽  
Failure Modes ◽  
Circuit Breaker ◽  
Reliability Evaluation ◽  
State Model ◽  
Reliability Indices ◽  
Minimal Cut Set ◽  
Minimal Cut ◽  
Cut Set ◽  
Three State Model

In this paper is presented a substations reliability analysis based upon substation’s component outage or failure modes. The switching actions can be modelled in the reliability evaluation indices we used the three-state model of the substation components (for example circuit breaker). The reliability indices are evaluated using the minimal cut-set method for each components of substation.

Assessing Stressors Related to Migration in Patients With Psychiatric Disorders

2012 ◽  
Vol 28 (4) ◽  
pp. 262-269 ◽  
Author(s):  
Matthias Johannes Müller ◽  
Suzan Kamcili-Kubach ◽  
Songül Strassheim ◽  
Eckhardt Koch
Keyword(s):  
Interrater Reliability ◽  
Item Analysis ◽  
Global Assessment Of Functioning ◽  
Family Conflicts ◽  
Response Options ◽  
Reliability Indices ◽  
Dsm Iv ◽  
Functional Relevance ◽  
Sum Scores ◽  
Gaf Scores

A 10-item instrument for the assessment of probable migration-related stressors was developed based on previous work (MIGSTR10) and interrater reliability was tested in a chart review study. The MIGSTR10 and nine nonspecific stressors of the DSM-IV Axis IV (DSMSTR9) were put into a questionnaire format with categorical and dimensional response options. Charts of 100 inpatients (50 Turkish migrants [MIG], 50 native German patients [CON]) with affective or anxiety disorder were reviewed by three independent raters and MIGSTR10, DSMSTR9, and Global Assessment of Functioning scale (GAF) scores were obtained. Interrater reliability indices (ICC) of items and sum scores were calculated. The prevalence of single migration-related stressors in MIG ranged from 15% to 100% (CON 0–92%). All items of the MIGSTR10 (ICC 0.58–0.92) and the DSMSTR9 (ICC 0.56–0.96) reached high to very high interrater agreement (p < .0005). The item analysis of the MIGSTR10 revealed sufficient internal consistency (Cronbach’s α = 0.68/0.69) and only one item (“family conflicts”) without substantial correlation with the remaining scale. Correlation analyses showed a significant overlap of dimensional MIGSTR10 scores (r² = 0.25; p < .01) and DSMSTR9 scores (r² = 9%; p < .05) with GAF scores in MIG indicating functional relevance. MIGSTR10 is considered a feasible, economic, and reliable instrument for the assessment of stressors potentially related to migration.

Use of an auto-expansion circuit breaker in a ring main unit

1988 ◽  
Vol 135 (3) ◽  
pp. 219
Author(s):  
G. Bernard ◽  
G. Perrissin ◽  
J. Marzocca
Keyword(s):  
Circuit Breaker ◽  
Expansion Circuit

An hourglass-type electromagnetic isolator with negative resistance electromagnetic shunt circuit

2020 ◽  
Vol 64 (1-4) ◽  
pp. 549-556
Author(s):  
Yajun Luo ◽  
Linwei Ji ◽  
Yahong Zhang ◽  
Minglong Xu ◽  
Xinong Zhang
Keyword(s):  
Vibration Isolation ◽  
Electromechanical Coupling ◽  
Coupling Effect ◽  
Negative Resistance ◽  
Isolation System ◽  
Amplitude Vibration ◽  
Vibration Responses ◽  
The Stability ◽  
Isolation Performance ◽  
Shunt Circuit

The present work proposed an hourglass-type electromagnetic isolator with negative resistance (NR) shunt circuit to achieve the effective suppression of the micro-amplitude vibration response in various advanced instruments and equipment. By innovatively design of combining the displacement amplifier and the NR electromagnetic shunt circuit, the current new type of vibration isolator not only can effectively solve the problem of micro-amplitude vibration control, but also has significant electromechanical coupling effect, to obtain excellent vibration isolation performance. The design of the isolator and motion relationship is presented firstly. The electromechanical coupling dynamic model of the isolator is also given. Moreover, the optimal design of the NR electromagnetic shunt circuit and the stability analysis of the vibration isolation system are carried out. Finally, the simulation results about the transfer function and vibration responses demonstrated that the isolator has a significant isolation performance.

ASSESSMENT OF ANATOMICAL & FUNCTIONAL SUCCESS IN EXTERNAL DACRYOCYSTORHINOSTOMY BY AIR BUBBLE TEST

2019 ◽  
Vol 3 (9) ◽  
Author(s):  
Dr. Vikas Tantuway
Keyword(s):  
Case Series ◽  
Invasive Procedure ◽  
Nasolacrimal Duct ◽  
Good Tool ◽  
Predictive Values ◽  
Reliability Indices ◽  
Air Bubble ◽  
Bubble Test ◽  
External Dacryocystorhinostomy ◽  
Anatomical Success

Aim: To assess reliability indices of Air Bubble Test (ABT) for anatomical and functional success in external Dacryocystorhinostomy (DCR). Methods: Prospective case series of nasolacrimal duct obstruction underwent DCR. Functional success defined as Munk score 0 & 1 & anatomical success as free irrigation at followup.ABT performed by putting antibiotic drops into eye& asking patient to exhale while keeping nose & mouth closed. Formation of bubbles at punctum considered as positive test. Specificity, sensitivity, positive & negative predictive values calculated. Results: There were 103 DCR in 97 patients(23 male,74 female)with mean age 45.56 yr. Anatomical and functional success was 99.02% & 98.05%, respectively.ABT showed sensitivity 96.07%, specificity 100% for anatomical success after DCR. Sensitivity and specificity were 97.02% & 100% for functional success. Conclusion: As non-invasive procedure ABT is a good tool to assess success of DCR, though lacrimal syringing remains the gold standard. Keywords: Anatomical, Dacryocystorhinostomy & Air Bubble Test.

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