Science & Technology Development Journal - Engineering and Technology

A Using the Fuzzy Logic to Classify Vietnamese Women’s Shapes from 6 to 18 Years Old

2020-04-09T18:36:49+00:00

The paper presents research to establish a simulation program on the Fuzzy logic for the Vietnamese women from 6-18 years old in Ho Chi Minh City. The author used across statistical method, component analysis method, factor analysis method, ANOVA by the SPSS software to overall test the difference between groups, and using the simulation by the Matlab software in this research. This research classified body shapes by a combination of 3 height groups, such as low, medium, and high. They combined with the FFIT and BMI standards to produce the final result of having all 27 women shapes. The results of the groups used to put into the Fuzzy logic simulation program by the Matlab software with the MISO model. It had five variables for inputs, and the output was the result of the shape which needed to know. This is scientific research, so it applies to teach subjects in the field of costume design. Besides, it supports businesses, and fashion designers will have a basis for advice on choosing costumes that fit the body shape, as well as the object of measurement, will have an objective awareness of body shapes to give training directions, adjust the physique appropriately.

Econometric Model for Forecasting Electricity Demand of Industry and Construction Sectors in Vietnam to 2030

2020-04-09T18:36:47+00:00

An accurate forecasting for long-term electricity demand makes a major role in the planning of the power system in any country. Vietnam is one of the most economically developing countries in the world, and its electricity demand has been increased dramatically high of about 15%/y for the last three decades. Contribution of industry and construction sectors in GDP has been increasing year by year, and are currently holding the leading position of largest consumers with more than 50% sharing in national electricity consumption proportion. How to estimate the electricity consumption of these sectors correctly makes a crucial contribution to the planning of the power system. This paper applies an econometric model with Cobb Douglas production function - a top-down method to forecast electricity demand of the industry and construction sectors in Vietnam to 2030. Four variables used are the value of the sectors in GDP, income per person, the proportion of electricity consumption of the sectors in total, and electric price. Forecasted results show that the proposed method has a quite low MAPE of 7.66% for long-term forecasting. Variable of electric price does not affect the demand. This is a very critical result of the study for authority governors in Vietnam. In the base scenario of the GDP and the income per person, the forecasted electricity demands of the sectors are 112,853 GWh, 172,691 GWh, and 242,027 GWh in 2020, 2025, 2030, respectively. In high scenario one, the demands are 115,947 GWh, 181,591 GWh, and 257,272 GWh, respectively. The above values in the high scenario are less than from 9.0% to 15.8 % of that of the based on in the Revised version of master plan N0. VII.

Determine the location and capacity of energy storage in the power system using the improved Min-Cut algorithm

2020-04-09T22:40:02+00:00

This paper aims to exhibit of optimal location and capacity of energy storage (ES) in electricity development planning, including transmission expansion planning (TEP) and generation expansion planning (GEP). Renewable energy sources are being developed in the world in order to replace the increasingly exhausting and polluting fossil energy sources. However, the energy generation of these types cannot be intentionally controlled but depends on natural conditions. To support the defects that renewable energy causes, energy storage systems have been studied and applied. Developing energy storage to charge cheap energy and provide higher prices in the electricity market is one of the issues that have being attention recently. Although choosing the proper location to place is a great challenge. A number of algorithms have been researched for a long time to find suitable locations for GEP; heuristic algorithms have been used in recent years because of their flexibility and wide range. The heuristic approaches, although being varied over time to become more and more effective search engines, but the problem is withheld into local extremes during searching, the number of too many loops when applied to large network systems... are still being researched and overcome by scientists for heuristic algorithms. On the other hand, the Max-Flow-Min-Cut (MFMC) algorithm has been applied to determine thyristor controlled series compensation (TCSC) to manage congestion that also has been of interest to many researchers but it has some limitations. The MFMC algorithm will be improved more effectively to eliminate congestion collaborate with a heuristic in the paper, and the simulation results tested to determine the position and power of ES on the 24 bus IEEE system showed the algorithm's feasibility.

The optimal generator dispatching with uncertain conditions for grid-connected microgrid

2020-04-09T23:08:30+00:00

Nowadays, the penetration of wind and solar sources is relatively high in Micro Grid. Wind speed and solar radiation forecasting hardly gives an exact value and leads to the values in intervals. Therefore forecasted output powers of these sources are also in the intervals. The constraint on power balance in Micro Grid has the right-hand-side uncertainty, in the interval. So for Micro-Grid in grid connection mode, the presence of the distributed generations based on wind and solar energy sources makes optimal dispatching problems of distributed generations become an uncertainty problem. The optimal solutions for the lower and upper ends of this interval are the best and the worst optimal solution. This paper proposes to treat the above problem as the optimal problem with two objectives: reach the best and the worst solution. The principle of fuzzy set and the Particle Swarm Optimization algorithm will be applied for solving the multi-objective problem. The final optimal value will belong to an interval. Meanwhile, the output power of the swing generator varies to respond to the uncertainty of wind and solar source power. An example of a low-voltage MG with three distributed generators is considered with two cases: connecting to the utility grid via the circuit breaker and via power controller.