Wednesday, July 20, 2011

Top Apps That You Need to Have in Your iPhone 5

When you own your iPhone 5 soon, you will find that having these 5 apps in your iPhone will surely make your iPhone 5 more compatible with your life. These are apps that fit your both entertainment and working needs. The jail break versions apps are more preferable because they are cheaper and more varied than the original version. It is very easy to find the shops online where you can get any kind of apps that you need for your new iPhone 5. The first app that you should have is social networking apps for iPhone. You can have Facebook for iPhone app which enables you to connect with your Facebook friends easily with your iPhone. Social network like is very useful to build network as well as to reach people around you.

The next app that you need to have in your iPhone 5 is navigation tool. NAVIGON MobileNavigator is an app that you can install in your iPhone to provide you GPS assistance. Compared to other navigation apps that you can have in the market, this NAVIGON app is excellent due to its friendly use features. Then you need to have working app called Documents to Go Premium. This app enables you to access works with your iPhone 5 easily with features that are offered by the app. If you put music as one of the most important thing in your life, then you must have a music player app like Slacker Personal Radio. With this app you will be able to double task your iPhone by playing music on your iPhone while you surf the internet. The last app that you must have in your iPhone 5 is communication and IMs app. You can have Skype for iPhone which will allow you to call to anyone cheaply.

Thursday, August 26, 2010

Thesis on Advanced Single-Stage Power Factor Correction Techniques

Five new single-stage power factor correction (PFC) techniques are developed for single-phase applications. These converters are: Integrated single-stage PFC converters, voltage source charge pump power factor correction (VS-CPPFC) converters, current source CPPFC converters, combined voltage source current source (VSCS) CPPFC converters, and continuous input current (CIC) CPPFC converters.

Integrated single-stage PFC converters are first developed, which combine the PFC converter with a DC/DC converter into a single-stage converter. DC bus voltage stress at light load for the single-stage PFC converters are analyzed. DC bus voltage feedback concept is proposed to reduce the DC bus voltage stress at light load. The principle of operations of proposed converters are presented, implemented and evaluated. The experimental results verify the theoretical analysis.

VS-CPPFC technique use a capacitor in series with a high frequency voltage source to achieve the PFC function. In this way, the input inductor is eliminated. VS-CPPFC AC/DC converters are developed, and their performance is evaluated. VS-CPPFC electronic ballasts with and without dimming function are also presented. The average lamp current control with duty ratio modulation is developed so that the lamp operates in constant power with a low crest factor over the line variation. The experimental results verify the CPPFC concept.

CS-CPPFC technique employs a capacitor in parallel with a high frequency current source to obtain the PFC function. The unity power factor condition and principle of operation are analyzed. By doing so, the switch has less switching current stress, and deals only with the resonant inductor current. Design considerations and experimental results of the CS-CPPFC electronic ballast are presented.

VSCS-CPPFC technique integrates the VS-CPPFC with the CS-CPPFC converters. The circuit derivation, unity power factor condition and design considerations are presented. The developed VSCS-CPPFC converters has constant lamp operation, low crest factor with a high power factor even without any feedback control.

CIC-CPPFC technique is developed by inserting a small inductor in series with the line rectifier for the conceptual VS-CPPFC, CS-CPPFC and VSCS-CPPFC circuits. The circuit derivation and its unity power factor condition are discussed. The input current can be designed to be continuous, and a small line input filter can be used. The circulating current in the resonant tank and the switching current stress are minimized. The average lamp current control with switching frequency modulation is developed, so the developed electronic ballast operates in constant power, low crest factor. The developed CIC-CPPFC electronic ballast has features of low line input current harmonics, constant lamp power, low crest factor, continuous input current, low DC bus voltage stress, small circulating current and switching current stress over a wide range of line input voltage.
Download this thesis.