Rivet is one of the connector or steel profiles, in addition to bolts in the weld. Rivets consist of a short steel malleable and shaped hemisphere bowl. At the moment in a state of plastic rivets, rivet hit with a hammer so it will form a head again on the other side. And usually, the rivet will expand to fill the entire hole. The use of rivets as a means of connecting more rigid when compared with the use of bolts. You can learn more about planning a connection profile using the tool steel rivets connecting.
In general, rivets are used to rivet the steel structure is installed in the garage and rivets are installed in the field. As explained above, rivets consist simply of a short steel, malleable and shaped hemisphere bowl. But it can also head of the rivet-shaped bonggolan. At the time of the rivet is in a plastic, rivets hit with a hammer so it will form a head again on the other side, and rivet it expands and fills the entire hole.
Tuesday, April 24, 2012
Efficiency Optimization Method Based On Radial Basis Function Neural Network In The Induction Motor Drive As A Ship Electrically Powered Propellers
This study developed a method of control of the driving engine / electric-powered propulsion of ships. The driving engine in this study has a propeller Fixed Pitch Propeller (FPP) which is set using the rotation axis induction motor. The method aims to control the speed rotary shaft at the same time optimizing the efficiency of electric motors driving the propulsion load varying.
Efficiency of optimization methods pursued through three major stages. In the first phase done modeling input-output relationship of control systems and stability analysis of electric-powered ship propulsion systems. The analysis showed that the ship propulsion systems based on shaft speed control is a stable system with 30 dB Gain Margin, Phase Margin 80 ° and tolerance Gain additional 34 systems.
In the second stage is designed rotor resistance estimator of induction motors. Estimator is required because of its location on the rotor, can not be measured and its value varies with temperature as an induction motor. This estimator works using information measurements of voltage, stator current and shaft speed. In this study the resulting contribution of adaptive computing to track the actual value of rotor resistance. Adaptive method is used for calculating the position of the rotor flux angle. This strategy can reduce the tracking time span of 1:42 minutes on conventional methods to 3:39 seconds.
In the Three Phase Induction Motors efficiency to be optimized. Efficiency optimization done by regulating the rotor flux. Rotor flux can be set via the d-axis stator current.
Algorithms Neural Nets (ANN) type of Radial Basis Function Neural Network (RBFN) was developed to determine the d-axis stator current optimum. To see the benefits of the method developed, RBFN method is compared with existing models. RBFN method could improve efficiency, particularly at the shaft speed of 3.2 revolutions per second, where the induction motor efficiency can be increased from 26.86% in the conventional method to 62.05% in the RBFN method. Based on the scenario selected trips, on ships 400 DWT, increased efficiency is equivalent to 17 532 kWh of energy savings. Increased efficiency is equivalent to fuel savings and emission reductions Liter 3059.86 6085.36 kg-CO2 gas.
Tuesday, April 17, 2012
After the devastation Hurricane Katrina left on New Orleans years ago, my husband and I had spent many months in the region helping re build. It had all been a labor of love and we found ourselves falling deeply for the city and its people. After some time, we decided to find a home to rent so we could spend more time there helping out and vacationing. I was more than pleased with our tiny little 2 bedroom bungalow and found ways to make it feel like home away from home. I contacted New Orleans Satellite TV and got a great package to help us kick back and unwind after a full day of either helping out or soaking up the culture. It is so nice having a place like this to call our own and I could see us easily making this a permanent home for us in the years to come. We’ve made so many friends and we feel it was our calling to come and help when so many people needed it. It feels like a true blessing came from such a terrible act of nature. We found our calling and we found a city that we love more and more everyday.