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Firefly algorithm based reactive power control of an isolated wind-diesel hybrid power system

For a robust voltage control of the system, controllers of proportional and integral type have been incorporated for AVR of the excitation system of the synchronous generator and SVC. The controller parameters are optimized using firefly algorithm (FA). The dynamic response of the system has been tested for different degrees of load disturbances plus variable nature of the wind system.

10/19/2021 6:34:12 AM +00:00

Evaluation of crack propagation phenomenon in bituminous mix

Crack propagation was experimentally simulated using semicircular specimen with a crack initiated on one side. The work shows that the rate of crack propagation can be described by a power relationship between the stiffness of the mixture and the number of cycles to failure, which is mixture and binder dependent.

10/19/2021 6:34:03 AM +00:00

Design fabrication and analysis of tri-wheeled electric vehicle

In daily life we can observe the difficulties of carrying the patients, old people, physically handicapped in public places like airports, railway stations, bus stands, hospitals, college campuses etc. To aid such people we prepared an electric tri-car to ease the task of carrying them. Moreover, it is a multipurpose vehicle to carry pilgrims in pilgrim places, to carry inspection teams in industries, estates or campuses etc.

10/19/2021 6:33:27 AM +00:00

Comparison of PI/Fuzzy techniques for compensation of unbalanced voltages in grid connected PMSG based wind turbine

This paper proposes an effective controller for grid connected wind turbine based permanent magnet synchronous machine for improving unbalanced voltages. In this paper, we proposed a comparative analysis under different controllers like PI and Fuzzy Controller to PMSG system. A control structure is designed based on the positive sequence reference signals.

10/19/2021 6:33:15 AM +00:00

Analysis over engine mount vibrational

This paper analysis the engine vibration on the engine mount for heavy duty engines, in vehicle chassis mount of engine is major role So, vibration design of engine mount is one of the main items on the phase of vehicle development, the design should be optimized considering various design variables and uncertainties.

10/19/2021 6:33:05 AM +00:00

An article on nonlinear waves in plasmas

A Plasma is a partially or fully ionized gas, where ionization and recombination are balanced to keep the ionized gas to be charge-neutral as a whole. If the charged neutrality is broken, a large electric field maybe locally created to drive plasma unstable. In this sense, charge neutrality (quasi-charge neutrality) is an essential ingredient of plasmas. Plasma, being a collection of charged particles, respond strongly and collectively to electromagnetic fields through long-range Coulomb interaction.

10/19/2021 6:32:39 AM +00:00

A survey on different methods of edge detection

Edge detection is a basic analogy of image processing. It is successful in detecting and extracting the objects features . It is the set of mathematical methods whose goal is to identifying points and shapes in a digital image of 2d geometric shapes to what place changes sharply the image brightness. A survey of diverse methodologies of edge detection are provided here.

10/19/2021 6:32:28 AM +00:00

A Neuro-fuzzy based SVPWM technique for PMSM

This paper proposes a concept of Neuro-fuzzy based control strategy which is used for controlling the PMSM. The total work mainly concentrates on optimum control of PMSM with maximum voltage utilization with less switching losses.

10/19/2021 6:32:09 AM +00:00

A fuzzy based SFCL for fault current limiter in distribution system

For this a fuzzy based Super Conducting Fault Current Limiter is the best electric equipment which is used for reducing the severe fault current levels. In this paper, we simulated the unsymmetrical faults with fuzzy based superconducting fault current limiter. In our analysis we had the following conclusions.

10/19/2021 6:31:54 AM +00:00

A fuzzy based PV-APF controller for compensating current harmonics

The main aim of this paper is to compensate a current harmonics in PV-APF system using Fuzzy Logic Controller. A 3- Ф 3-wire system is proposed in this paper which consists of PV system, a dc/dc converter which is controlled by MPPT, three phase VSC to act as APF and Non-Linear Load. The main theme of this INC MPPT is to efficiency from the PV system.

10/19/2021 6:31:39 AM +00:00

Ứng dụng phương pháp vi sóng tổng hợp nhanh lớp hạt và màng lọc ZIF-8 để phân tách hỗn hợp khí propylene/propane

Đề tài này sử dụng phương pháp vi sóng để tổng hợp một cách nhanh chóng lớp hạt và tiếp sau đó là màng lọc ZIF-8. Kết quả cho thấy, màng lọc thu được có chất lượng và thể hiện độ phân tách cao đối với hỗn hợp propylene/propane. Lượng truyền qua của propylene đạt 105×10-10 mol.m-2s-1Pa-1, và hệ số phân tách propylene/propane đạt được là 70. Màng lọc còn cho thấy độ bền, độ lặp lại cũng như độ ổn định cao khi thực hiện phân tách propylene/propane gián đoạn cũng như liên tục. Mời các bạn cùng tham khảo!

10/18/2021 11:28:20 PM +00:00

Đánh giá độc tính và khả năng tăng tín hiệu tương phản ảnh MRI của vật liệu nano từ Fe3 O4 @PLA-PEG trên mô hình in vitro

Bài nghiên cứu này tập trung đánh giá độc tính in vitro của SPIONs được nghiên cứu chế tạo trong nước cũng như nghiên cứu thử nghiệm của loại vật liệu này với vai trò làm tác nhân tăng tín hiệu hiện ảnh cộng hưởng từ hạt nhân. Để hiểu rõ hơn mời các bạn cùng tham khảo nội dung chi tiết của bài viết này.

10/18/2021 11:27:45 PM +00:00

Tackle some student’s problems through exercise paradox, sophistry in particle kinetics and particle dynamics in physics textbook for grade 10

Teaching Physics in high schools is associated with teaching and solving exercises, thereby forming and developing for students major qualities and general competencies; at the same time, preventing and avoiding for students some common mistakes.

10/18/2021 5:45:23 PM +00:00

Mô phỏng tạo ảnh bán thực địa ứng dụng trong ngụy trang ảnh nhiệt

Bài viết trình bày một phương pháp tạo ảnh bán thực nghiệm. Trên cơ sở nguyên lý phóng đại ảnh của hệ quang học và ảnh hưởng của các điều kiện môi trường lên chất lượng ảnh (suy hao năng lượng bức xạ) và bằng phương pháp mô phỏng trong phòng thí nghiệm, đã xác định được hệ số suy hao với điều kiện môi trường xác định.

10/18/2021 12:49:57 PM +00:00

Áp dụng phương pháp tối ưu quang học hạn chế hiệu ứng narcissus trong các thiết bị ảnh nhiệt

Mục tiêu nghiên cứu là giải pháp kĩ thuật áp dụng trong quá trình thiết kế và tối ưu thiết kế quang học nhằm hạn chế ảnh hưởng của hiệu ứng Narcissus. Các hệ thống ảnh nhiệt sử dụng đầu thu có làm lạnh thường bị ảnh hưởng lớn bởi hiệu ứng Narcissus, kể cả đối với vùng phổ làm việc 3-5 µm [MWIR] cũng như vùng 7-14 µm [LWIR], các kĩ thuật xử lí ảnh được dùng để khử bất đồng nhất (NUC) không thể triệt tiêu hết.

10/18/2021 12:49:28 PM +00:00

Lecture Microwave and Satellite Systems - Week 7: Multiple Access Techniques

Lecture Microwave and Satellite Systems - Week 7: Multiple Access Techniques present the content: multiple access system, TDMA, TDMA frame structure, time division multiple access and ALOHA, FDMA, code division multiple access,...

10/18/2021 12:44:17 PM +00:00

Lecture Microwave and Satellite Systems - Week 5: Communication Satellite Link Design

Lecture Microwave and Satellite Systems - Week 5: Communication Satellite Link Design present the content: introduction, general link design equations, system noise temperature, C/N and G/T Ratios,...

10/18/2021 12:44:09 PM +00:00

Lecture Microwave and Satellite Systems - Week 2: Magnetron, Travelling-Wave Tube

Lecture Microwave and Satellite Systems - Week 2: Magnetron, Travelling-Wave Tube present the content: traveling-wave tube, traveling-wave-tube amplifier, cavity magnetron, construction and operation,...

10/18/2021 12:15:34 PM +00:00

Lecture Microwave and Satellite Systems - Week 6: Communication Satellite Link Design

Lecture Microwave and Satellite Systems - Week 6: Communication Satellite Link Design present the content: uplink design, complete link design, combining equation,...

10/18/2021 12:15:25 PM +00:00

Lecture Microwave and Satellite Systems - Week 4: Characteristics of Satellite Communication System

Lecture Microwave and Satellite Systems - Week 4: Characteristics of Satellite Communication System present the content: fundamentals of satellite systems, general and technical characteristics of a satellite communication system, advantages of satellite communication,...

10/18/2021 12:14:59 PM +00:00

Lecture Microwave and Satellite Systems - Week 3: Fundamentals of Satellite Systems

Lecture Microwave and Satellite Systems - Week 3: Fundamentals of Satellite Systems present the content: evolution of communication satellites, synchronous satellites, international regulation frequency coordination and ITU-R, satellite frequency allocations and band spectrum,...

10/18/2021 12:14:26 PM +00:00

Lecture Microwave and Satellite Systems - Week 12: Satellite Earth Station

Lecture Microwave and Satellite Systems - Week 12: Satellite Earth Station present the content: introduction, earth station design requirement, earth station sub system, earth station technology,...

10/18/2021 12:14:15 PM +00:00

Lecture Microwave and Satellite Systems - Week 11: Communication Satellite Sub-systems

Lecture Microwave and Satellite Systems - Week 11: Communication Satellite Sub-systems present the content: communication satellite sub-systems, power supply subsystems, repeaters, antenna sub-system, electric power supply, solar cells,...

10/18/2021 12:13:53 PM +00:00

Lecture Microwave and Satellite Systems - Week 8: Satellite Orbit Mechanics

Lecture Microwave and Satellite Systems - Week 8: Satellite Orbit Mechanics present the content: satellite orbit mechanics, synchronous orbit, orbital parameters, Kepler’s law, orbital aspects, types of orbits,...

10/18/2021 12:13:37 PM +00:00

Vật liệu nano trong lĩnh vực xúc tác – hấp phụ và cuộc sống

Bài viết trình bày tính chất hóa lý quan trọng của vật liệu nano đã và đang ứng dụng rộng rãi trong công nghiệp hóa học, công nghệ bảo vệ môi trường và nhiều lĩnh vực khác. Công nghệ nano là một lĩnh vực khoa học – công nghệ hết sức đa dạng, nhiều thách thức và cũng đầy triển vọng. Mời các bạn cùng tham khảo!

10/18/2021 12:54:44 AM +00:00

Lecture General Physics 2 - Chapter 24: Wave Optics

Lecture General Physics 2 - Chapter 24: Wave Optics. After studying this section will help you understand: wave optics, interference, conditions for interference, producing coherent sources, Young’s double slit experiment, resulting interference pattern,...

10/17/2021 4:02:06 PM +00:00

Lecture General Physics 2 - Chapter 13: Vibrations and Waves

Lecture General Physics 2 - Chapter 13: Vibrations and Waves. After studying this section will help you understand: Hooke’s law, Hooke’s law force, mass system, simple harmonic motion, amplitude, period and frequency, elastic potential energy, energy transformations,...

10/17/2021 4:01:30 PM +00:00

Lecture General Physics 2 - Chapter 14: Sound

Lecture General Physics 2 - Chapter 14: Sound. After studying this section will help you understand: producing a sound wave, using a tuning fork to produce a sound wave, categories of sound waves, speed of sound in a liquid,...

10/17/2021 4:00:56 PM +00:00

Lecture General Physics 2 - Chapter 26: Relativity

Lecture General Physics 2 - Chapter 26: Relativity. After studying this section will help you understand: basic problems, foundation of special relativity, Galilean relativity, luminiferous ether, Michelson-Morley experiment, Michelson-Morley equipment,...

10/17/2021 4:00:32 PM +00:00

Lecture General Physics 2 - Chapter 22: Reflection and Refraction of Light

Lecture General Physics 2 - Chapter 22: Reflection and Refraction of Light. After studying this section will help you understand: a brief history of light, the particle nature of light, dual nature of light, geometric optics – using a ray approximation,...

10/17/2021 4:00:03 PM +00:00