scholarly journals ANALISA PEMBEBANAN PADA GENERATOR LISTRIK KAPAL PENANGKAP IKAN STUDI KASUS PADA KM. MARADONA

2020 ◽  
Vol 2 (1) ◽  
pp. 63
Author(s):  
Bobby Demeianto ◽  
Riki Peri Ramadani ◽  
Iskandar Musa ◽  
Yuniar Endri Priharanto
Keyword(s):  
Electric Current ◽  
Electrical Power ◽  
Fishing Vessel ◽  
Electric Generator ◽  
Average Percentage ◽  
Average Value ◽  
Maximum Value ◽  
Three Phase ◽  
Average Current ◽  
Current Value

Efficiency value is a measure that can inform us that a machine that operates can be said to be efficient or not. This study aims to find the efficiency value of the electric generator on the fishing vessel KM. Maradona. In addition, this study also aims to find the average percentage value of electric current on each phase of the generator and also to find the average value of the percentage imbalance of load sharing in three-phase electrical installations in KM. Maradona. From the calculation, it is found that the percentage of imbalance of three-phase electrical installations KM. Maradona when the generator operates can reach 31.11%. From the calculation, it is also found that the average percentage load on the electric generator of KM. Maradona maximum value is 22.35% with an average current value of 25.50 Ampere. Directly proportional to the maximum average current value, the maximum electrical power value of KM. Maradona is only at 16.80 kVA with an efficiency value of 22.40%.

scholarly journals Evapotranspiration and estimation of aerodynamic and stomatal conductance in a fragment of Atlantic Forest in mantiqueira range region, MG

CERNE ◽  
2010 ◽  
Vol 16 (1) ◽  
pp. 32-40 ◽  
Author(s):  
Donizete dos Reis Pereira ◽  
Carlos Rogério de Mello ◽  
Antônio Marciano da Silva ◽  
Sílvia de Nazaré Monteiro Yanagi
Keyword(s):  
Stomatal Conductance ◽  
Water Balance ◽  
Atlantic Forest ◽  
Environmental Modeling ◽  
Average Value ◽  
Maximum Value ◽  
Minas Gerais State ◽  
Forest Remnants ◽  
Forested Areas ◽  
And Storage

Understanding hydrologic behavior in forested areas, not least the Brazilian Atlantic Forest, is of fundamental importance for environmental modeling. This work aimed to estimate evapotranspiration values in Atlantic Forest remnants of Mantiqueira Range region using water balance calculations, and to estimate parameters (stomatal and aerodynamic conductances) for this vegetation cover using the Penman-Monteith model. In terms of water balance, evapotranspiration accounted for 89% of total precipitation, deep percolation accounted for 13.6% and storage variation was slightly negative over the analysis period. Canopy aerodynamic conductance (g a) presented a minimum value of 0.0921 m s-1, a maximum value of 0.1000 m s-1 and an average value of 0.0993 m s-1. Stomatal conductance (g s) varied from 0.001 to 0.0046 m s-1, with an average value of 0.0022 m s-1, being influenced by environmental conditions, especially by soil water availability. It was observed that the application of the Penman-Monteith model with average parameter fit (g a and g s) provided good accuracy, especially over the dry season, therefore it can be applied to studies of forest hydrology in fragments of Atlantic Forest in the Mantiqueira Range region, Minas Gerais state.

Power Quality Issues and Solutions – Review

2015 ◽  
Vol 16 (4) ◽  
pp. 357-384 ◽  
Author(s):  
Suresh Mikkili ◽  
Anup Kumar Panda
Keyword(s):  
Power Quality ◽  
Power Distribution ◽  
Distribution Systems ◽  
Reactive Power ◽  
Electrical Power ◽  
Economic Loss ◽  
Nonlinear Loads ◽  
Broad Perspective ◽  
Three Phase ◽  
Quality Issues

Abstract Electrical power quality has been an important and growing problem because of the proliferation of nonlinear loads such as power electronic converters in typical power distribution systems in recent years. Particularly, voltage harmonics and power distribution equipment problems result from current harmonics produced by nonlinear loads. The Electronic equipment like, computers, battery chargers, electronic ballasts, variable frequency drives, and switch mode power supplies, generate perilous harmonics and cause enormous economic loss every year. Problems caused by power quality have great adverse economic impact on the utilities and customers. Due to that both power suppliers and power consumers are concerned about the power quality problems and compensation techniques. Power quality has become more and more serious with each passing day. As a result active power filter gains much more attention due to excellent harmonic and reactive power compensation in two-wire (single phase), three-wire (three-phase without neutral), and four-wire (three-phase with neutral) ac power networks with nonlinear loads. However, this is still a technology under development, and many new contributions and new control topologies have been reported in the last few years. It is aimed at providing a broad perspective on the status of APF technology to the researchers and application engineers dealing with power quality issues.

scholarly journals A new approach to three-phase asynchronous motor model for electric power system analysis

2021 ◽  
Vol 12 (4) ◽  
pp. 2083
Author(s):  
Laura Collazo Solar ◽  
Angel A. Costa Montiel ◽  
Miriam Vilaragut Llanes ◽  
Vladimir Sousa Santos
Keyword(s):  
Power Systems ◽  
Reactive Power ◽  
Mechanical Load ◽  
Asynchronous Motor ◽  
Electrical Power ◽  
Variable Load ◽  
Electrical Power Systems ◽  
Active And Reactive Power ◽  
Voltage Variation ◽  
Three Phase

In this paper, a new steady-state model of a three-phase asynchronous motor is proposed to be used in the studies of electrical power systems. The model allows for obtaining the response of the demand for active and reactive power as a function of voltage and frequency. The contribution of the model is the integration of the characteristics of the mechanical load that can drive motors, either constant or variable load. The model was evaluated on a 2500 kW and 6000 V motor, for the two types of mechanical load, in a wide range of voltage and frequency, as well as four load factors. As a result of the evaluation, it was possible to verify that, for the nominal frequency and voltage variation, the type of load does not influence the behavior of the powers and that the reactive power is very sensitive to the voltage variation. In the nominal voltage and frequency deviation scenario, it was found that the type of load influences the behavior of the active and reactive power, especially in the variable load. The results demonstrate the importance of considering the model proposed in the simulation software of electrical power systems.

scholarly journals PENERAPAN MODEL PEMBELAJARAN KOOEPERATIF TIPE MAKE A MATCH UNTUK MENINGKATKAN HASIL BELAJAR IPS SISWA KELAS V SEKOLAH DASAR

2018 ◽  
Vol 7 (1) ◽  
pp. 170
Author(s):  
Samsur Samsur
Keyword(s):  
Student Learning ◽  
Learning Outcomes ◽  
Implementation Strategies ◽  
Learning Models ◽  
Class V ◽  
Average Percentage ◽  
Average Value ◽  
Percentage Improvement ◽  
Match Type ◽  
Academic Year

This research is motivated by the lack of IPS student learning outcomes can be seen from the results of thestudents' social studies class V SD Negeri 54 Sebangar with an average value of 60.65. Therefore, theresearchers provide an alternative implementation strategies in the classroom to the application of learningmodels kooeperatif make a match type in the class V SD Negeri 54 Sebangar in the academic year 2014/2015.This research aims to improve learning outcomes IPS V grade students of SD Negeri 54 Sebangar with theapplication of learning models kooeperatif make a match type in the class V Implementation Strategy. Form ofresearch is the Classroom Action Research (PTK) with 2 cycles. Based on research data anlisis after applying oflearning models kooeperatif make a match type, the average percentage of the activity of teachers in the firstcycle 74.99% increased to 91.06% in the second cycle. The average percentage of student activity alsoincreased, namely 67.85% in the first cycle increased to 82.14% in the second cycle. Student learning outcomesin basic score by the average value of 60.65 and the first cycle increased with an average value of 75.00 classwith a 23.66% increase in the percentage of learning outcomes and the percentage of students who completed84.61%, and the second cycle increased again by an average of 82.30 with the percentage improvement classlearning outcomes 35.69% and the percentage of students who completed 88.46%. These results indicate that theapplication the application of learning models kooeperatif make a match type in the class V IPS grade studentsof SD Negeri 54 Sebangar.

scholarly journals Enhancement of the Thermal Performance Characteristics of an Electrical Power Transformer

2020 ◽  
pp. 94-112
Author(s):  
Nawras Mohammed Azbar ◽  
Hayder Mohammad Jaffal ◽  
Basim Freegah
Keyword(s):  
Thermal Performance ◽  
Thermal Load ◽  
Model Comparison ◽  
Experimental Finding ◽  
Power Transformer ◽  
Electrical Power ◽  
Operational Parameters ◽  
3D Numerical Simulation ◽  
Cooling Performance ◽  
Three Phase

A 3D numerical simulation was conducted to test the effects of the geometrical and operational parameters on the cooling performance of a three-phase electrical distribution transformer (250 kVA oil natural air natural (ONAN)). The geometric parameters include the shape of the transformer (rectangular, circular, and hexagonal), fins shape (rectangular, semicircular, and trapezoidal) as well it arrangement (asymmetric fin heights and perforated fins). Both of oil temperature and thermal load have been used as boundary conditions. In order to verify the reliability of the numerical model, comparison between numerical results and experimental finding has been done. The results have indicated that the circular and hexagonal shapes reduced the average oil temperature by 3.4% and 4.7%, respectively, compared to the traditional transformer shape (rectangular). Furthermore, the lowest average oil temperature was observed for the trapezoidal fin, followed by the rectangular and semicircular fins. Additionally, it has been noticed that the asymmetric fin heights of the trapezoidal and perforated trapezoidal fins been contributed to the improvement of the cooling performance of the transformer. Furthermore, the best thermal performance was obtained with the trapezoidal perforated fin to compared other arrangement of fins. Finally, the highest reduction in oil has been obtained by the use of hexagonal transformer with a perforated trapezoidal fin approximately by 12% compared to traditional rectangular transformer. Hence, it can be concluded that the shape of the transformer and fins play an important role in thermal performance of such systems.

scholarly journals Field and Laboratory-based Approach for the Determination of Friction Angle of Geological Discontinuities of Malaysian Granites

2011 ◽  
Vol 28 (2) ◽  
pp. 151 ◽  
Author(s):  
R. A Ghani ◽  
T. L Goh ◽  
A. M Hariri ◽  
Y. N Baizura
Keyword(s):  
Friction Angle ◽  
Roughness Coefficient ◽  
Average Value ◽  
Peak Friction Angle ◽  
Maximum Value ◽  
Wide Range ◽  
Discontinuity Surfaces ◽  
Geological Discontinuities ◽  
Range Of Values

The basic friction angle, Φb for artificially sawn discontinuity planes for fresh granite, as determined by tilt testing, has an average value of 30º. For the natural rough discontinuity surfaces, a wide range of values have been determined for the peak friction angle, Φpeak ranging from 47º to a maximum value of 80º, depending on the joint roughness coefficient (JRC). The average values of the friction angles for the different degrees of roughness were as follows: JRC 2–4 = 58°; JRC 6–8 = 60°; JRC 8–10 = 47°; JRC 12–14 = 60°; JRC 14–16 = 71° ; JRC 18–20 = 80°.

scholarly journals Physiological Values of P-Wave Dispersion in Silesian Breed Horses and Polish Primitive Horses

2013 ◽  
Vol 57 (1) ◽  
pp. 85-89
Author(s):  
Katarzyna Michlik ◽  
Agnieszka Noszczyk-Nowak ◽  
Urszula Pasławska ◽  
Izabela Janus ◽  
Józef Nicpoń
Keyword(s):  
Body Mass ◽  
Wave Dispersion ◽  
P Wave ◽  
P Wave Dispersion ◽  
Average Value ◽  
Maximum Value ◽  
Physiological Values ◽  
Physiological Value

Abstract Electrocardiographic examinations were performed on 45 Silesian breed horses (group K, 3-16-year-old, 16 stallions, 29 mares) and on 25 Polish Primitive breed horses (group P, 1.5-19-year-old, two stallions, six geldings, 17 mares). Einthoven and chest leads were used. P-wave dispersion was electronically evaluated. There was no correlation between P-wave dispersion and other ECG parameters, age, sex, body mass, or month of pregnancy. The average value of P-wave dispersion for all horses was 30.77 ms (SD 3.92 ms), however in particular groups it was: in group P - 31.89 ms (SD 3.07 ms), and in group K - 30.15 ms (SD 4.27 ms). The maximum value of P-wave dispersion in the studied population was 40 ms, in groups P and K - 37,6 ms and 40 ms, respectively. The physiological value of P-wave dispersion for the group of horses was below 45 ms.

scholarly journals Analysis Of Critical Thinking Skill Level Of Students Smp Negeri 2 Padang about Environmental Pollution

2018 ◽  
Vol 3 (1) ◽  
pp. 1
Author(s):  
Novia Daniati ◽  
Dezi Handayani ◽  
Relsas Yogica ◽  
Heffi Alberida
Keyword(s):  
Middle School ◽  
Critical Thinking ◽  
Environmental Pollution ◽  
Thinking Skills ◽  
Critical Thinking Skills ◽  
Average Percentage ◽  
Average Value ◽  
Descriptive Research ◽  
A Value ◽  
Public Middle School

Curriculum of 2013 requires students to be able to think critically. This critical thinking ability can be trained by using questions that have indicators of critical thinking, besides those questions must also have cognitive levels C4 (analyze), C5 (evaluate), and C6 (synthesize). Padang Public Middle School 2 has implemented 2013 Curriculum in learning, but students' critical thinking skills are unknown. This research is a descriptive research. The method used in this research is descriptive method. The subject of the study consisted of 48 students of class VII of SMP Negeri 2 Padang. The data obtained in this study was obtained through test techniques. The test used is a description test. The test instruments used will be validated and analyzed first. Analysis of this instrument includes the level of difficulty, differentiation and reliability. Test instruments were tested before being used. This study produces data that the level of critical thinking skills of seventh grade students in Padang State Middle School is still in non-critical qualifications with a percentage average value of 48.53%. Indicators with the highest average percentage to the lowest, namely; the inference indicator obtained a score of 69.96% with quite critical qualifications; the indicator gives a basic statement obtained a value of 60.62% with less critical qualifications; the indicator estimates that a value of 53.12% is obtained with non-critical qualifications; the indicator gives an advanced statement obtained a value of 44.39% with non-critical qualifications, and; basic indicators of decision making obtained a value of 14.58% with non-critical qualifications. Keywords: Critical Thinking, Environmental Pollution, Descriptif

scholarly journals Identification of Disease on Leaves Soybean using Modified Otsu and Learning Vector Quantization Neural Networks

Kursor ◽  
2018 ◽  
Vol 9 (3) ◽  
Author(s):  
Candra Dewi ◽  
Muhammad Sa’idul Umam ◽  
Imam Cholissodin
Keyword(s):  
Vector Quantization ◽  
Threshold Value ◽  
Learning Vector Quantization ◽  
Training Data ◽  
Blue Color ◽  
Phakopsora Pachyrhizi ◽  
Average Value ◽  
Maximum Value ◽  
Otsu Method ◽  
Soybean Leaf

Disease of the soybean crop is one of the obstacles to increase soybean production in Indonesia. Some of these diseases usually are found in the leaves and resulted to the crop become unhealthy. This study aims to identify disease on soybean leaf through leaves image by applying the Learning Vector Quantization (LVQ) algorithm. The identification begins with preprocessing using modified Otsu method to get part of the diseases on the leaves with a certain threshold value. The next process is to identify the type of disease using LVQ. This process uses the minimum value, the maximum value and the average value of the red, green and blue color of the image. The testing conducted in this study is to identify two diseases called Peronospora manshurica (Downy Mildew) and phakopsora pachyrhizi (Karat). The result of testing by using 60 training data and the value of all recommendations parameters obtained the highest accuracy of identification is 95% %, but the more stable accuracy is 90%. This result shows that the method perform quite well identification of two mentioned disease.

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