Multilevel inverters produce a staircase output voltage from DC voltage sources. Requiring great number of semiconductor switches is main disadvantage of multilevel inverters. The multilevel inverters can be divided in two groups: symmetric and asymmetric converters. The asymmetric multilevel inverters provide a large number of output steps without increasing the number of DC voltage sources an...

User-generated travelogues can generate much geographic data, containing abundant semantic and geographic information that reflects people’s movement patterns. The tourist movement patterns in travelogues can help others when planning trips, or understanding how people travel within certain regions. The trajectory data in travelogues might include tourist attractions, restaurants and other loca...

We explore the characteristics of households and villages in which orphans are resident in two areas of Malawi. We first review pertinent themes in qualitative data collected in our research sites. Then, using spatial analysis, we show how positive and negative clusters of orphans - which we term orphanhood "hotspots" and "coldspots" - can be found at the village and sub-village levels. In the ...

Please be advised that this information was generated on 2017-02-09 and may be subject to change.

Byrne and colleagues present a paper on a timely topic with potentially important results. However, we think that issues in the design and analysis complicate the interpretation and limit the generalizability of the findings. Specifically, the details of the small volume correction used in the primary analysis are not adequately described and, moreover, the results do not appear to be corrobora...

The multilevel inverters have highly desirable characteristics in high power high voltage applications. The multilevel inverter was started first with diode clamped multilevel inverter. Later, various configurations have been came into existence for many applications. However the multilevel inverters have some demerits such as requiring higher number of components, PWM control method is complex...