117 research outputs found
Modelling of a 3-phase induction motor under open-phase fault using matlab/simulink
The d-q model of Induction Motors (IMs) has been effectively used as an efficient method to analyze the performance of the induction machines. This study presents a step by step Matlab/Simulink implementation of a star-connected 3-phase IM under open-phase fault (faulty 3-phase IM) using d-q model. The presented technique in this paper can be simply implemented in one block and can be made available for control purposes. The simulated results provide to show the behavior of the star-connected 3-phase IM under open-phase fault condition
Optimal time repair of ventricular septal rupture post myocardial infarction
Ventricular septal rupture (VSR) is an uncommon complication of myocardial infarction (MI). The mortality rate of VSR is high. The management of VSR is including the stabilization of the hemodynamic status and surgical closure of the rupture. In spite of the agreement of experts on the necessity of surgical repair, the timing of VSR repair management remains unclear. In this review article, we evaluate the optimal time repair of VSR. To collect the data, Pubmed, EMBASE, and Cochrane Central Registry databases were searched for potentially suitable studies. Search terms were including “Ventricular Septal Rupture”, “Myocardial Infarction”, “Timing”, and “MI”. According to the result of the studies, it seems that the time between VSR detection and its repair is a determining factor in the survival or mortality of patients in post-myocardial infraction VSR. Studies showed that earlier surgical repair in VSR increases the risk of mortality, because in the early phase after MI, infarcted myocardium is very fragile, and it is very difficult surgical repair and increases the risk of recurrent septal defects. The longer time is needed for the heart and different body systems to adapt to the hemodynamic results of the abrupt left to right shunt. It seems that the best time for the operation is after the maturation of VSR with scarring at the edges of the defect. Moreover, in a large number of patients, it is not possible to delay the operation since they are at risk of severe heart failure and organ dysfunction. In these cases operation immediately after diagnosis of VSR is recommended to prevent further hemodynamic deterioration. In hemodynami-cally compromised patients, it may be considered to use a ventricular assist device, requiring an intra-aortic balloon pump (IABP), or extracorporeal membrane oxygenation (ECMO) preoperative to postpone the operation which leads to higher survival in post-MI-VSD
ANALISIS DAMPAK PANDEMI COVID-19 TERHADAP PENDAPATAN USAHA MIKRO KECIL DAN MENENGAH (STUDI KASUS INDUSTRI RUMAHAN KEMPLANG DI WILAYAH JAKABARING PALEMBANG)
This study aims to determine and analyze the impact of the Covid-19 pandemic on the income of the cracker/kemplang home industry in the Jakabaring District, Palembang City. The analytical method used in this research is a qualitative method with data collection techniques in the form of interviews, discussions with business actors and from several sources of other articles. From the research that has been carried out, it is found that the cracker/kemplang home industry continues to run its business, and the income earned by the cracker/kemplang home industry tends to be stable even in the Covid-19 pandemic situation. The factor that supports the traders to keep doing business is the awareness to continue to struggle to meet the needs of their daily lives. There are several attempts by business actors to increase an income, such as by adapting to market changes, providing good service to consumers and paying attention to the quality of goods to be sold to consumers
A Review of Wind Speed Estimation for Wind Turbine Systems Based on Kalman Filter Technique
This paper presents a review of wind speed estimation based on Kalman filter technique applied to wind turbine systems. Generally, wind speed measurement is performed by anemometer. The wind speed provided by the anemometer is measured at a single point of the rotor plane which is not the accurate wind speed. Also, using anemometer increases the system cost, maintenance, complexity and reduces the reliability. For these reasons, estimation of wind speed is needed for wind turbine systems. In this paper, the several wind speed estimation methods based on Kalman filter method used for wind turbine systems are reviewed
Students' Attitudes Towards The Implementation Of Gender Segregation In Universities
Background & Aim: The first principle in university is knowledge attaining. Recently, the idea of gender segregation in academic setting is suggested, so it was important to explore the students’ perspective about gender segregation. The aim of this study was to determine the attitude of students toward the implementation of gender segregation in universities in Golestan province in 2014.
Material & Methods: This cross-sectional study conducted on 209 students of universities in Golestan province using a self-made, valid and reliable questionnaire. Data were analyzed by SPSS.18 and descriptive statistics (mean, standard deviation) and inferential (Chi-square)
Results: 36.1 percent of the students had a positive attitude, and 68.4 percent had a negative attitude toward gender segregation in universities. There was no significant relationship between gender, marital status and ethnicity of students with their attitudes to the gender segregation in university (P<0.05). Both male and female students stated that “effect on education, having religion basis, and freedom of action” are the reasons for their positive attitudes toward gender segregation in universities.
Conclusion:The attitudes of students were favor toward gender segregation, however they believed that students should be involved in decision making and applying such important projects
PERAN PEMBERDAYAAN DAN KETERLIBATAN KERJA TERHADAP KEPUASAN KERJA DAN KINERJA: -
The aims of this study was to reveals the roles of empowerment and work involvement on job satisfaction and its impact on the performance of employees in the Ternate Agriculture Agency. The research designs were surveys and questionnaires. The population and sample in this study were the agricultural officials of Ternate City, totaling 135 employees, using the census method. Method of data analysis was Smart PLS 3.0.
The results indicated that 1) empowerment have a positively and significantly effect on job satisfaction, 2) job involvement have positively and significantly effect on job satisfaction, 3) job satisfaction have a positively and significantly effect on employee performance, 4) empowerment have a positively and significantly effect on employee performance, 5) job involvement have a positively and significantly effect on performance, 6) job satisfaction mediated on the effect of empowerment on employee performance and 7) Job satisfaction mediated the effect of work involvement on employee performance. These results indicate that the problem of poor performance in the Ternate Agriculture Agency is closely related to the variables of empowerment, job involvement, and job satisfaction. One of the novelty this research is placement of job satisfaction as a mediation variables
High performance speed control of single-phase induction motors using switching forward and backward EKF strategy
The aim of this research is to provide a high performance vector control of single-phase Induction Motor (IM) drives. It is shown that in the rotating reference frame, the single-phase IM equations can be separated into forward and backward equations with the balanced structure. Based on this, a method for vector control of the single-phase IM, using two modified Rotor Field- Oriented Control (RFOC) algorithms is presented. In order to accommodate forward and backward rotor fluxes in the presented controller, an Extended Kalman Filter (EKF) with two different forward and backward currents that are switched interchangeably (switching forward and backward EKF), is proposed. Simulation results illustrate the effectiveness of the proposed algorithm
A Novel Method for Rotor Field-Oriented Control of Single-Phase Induction Motor
This paper presents a novel rotor field-oriented control (RFOC) method for asymmetrical single-phase induction motor (SPIM). It is shown in this paper that by using a suitable transformation matrix (TM) for stator current variables, the asymmetrical equations of SPIM are transformed into symmetrical equations. Based on this similarity, a novel vector conrol technique for SPIM is presented. Performance of the proposed method is assessed using MATLAB/SIMULINK software. Simulation results showed the excellence speed and torque responses obtained using the proposed technique
Neither backward masking of T2 nor task switching is necessary for the attentional blink
Identification of the second of two targets
(T1, T2, inserted in a stream of distractors) is impaired
when presented within 500 ms after the first (attentional
blink, AB). Barring a T1-T2 task-switch, it is thought
that T2 must be backward-masked to obtain an AB
(Giesbrecht & Di Lollo, Journal of Experimental Psychology:
Human Perception and Performance, 24, 1454-
1466, 1998). We tested the hypothesis that Giesbrecht &
Di Lollo's findings were vitiated by ceiling constraints
arising from either response scale (experiment 1) or data
limitations (experiment 2). In experiment 1, digitdistractors
were replaced with pseudoletters to increase
task difficulty, bringing performance below ceiling. An
AB occurred without backward masking of T2. In
experiment 2, a ceiling-free procedure estimated the
number of noise dots needed for 80% T2 identification.
An AB was revealed: fewer noise dots were required
during the AB period than outside it. Both outcomes
confirm that an AB can be obtained without either
masking of T2 or task switching
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