The photo print quality of your images depends on the camera’s “megapixel rating.” The higher number of pixels your camera has, the higher the resolution (or sharpness) of your images—and the larger your prints can be without quality loss.



The number of pictures you can take varies depending on your camera model and complexity of the scene being photographed. To calculate how many pictures your card can hold, divide the capacity of your card by the average file size of your images. For example, if you have a 256MB card, and use a camera that has an average file size of 1.2MB, then 256 divided by 1.2 gives you approximately 213 pictures. As you change modes on your camera, the number of images will increase if you shoot in a lower resolution mode, and decrease if you shoot in a higher resolution mode.

MB = megabytes GB= gigabytes
* Average file size using cameras highest resolution JPEG mode. The actual number of images per card will vary and depends on the camera model and compatibility of the scene being photographed.

Source: Kodak C433 4.0 Megapixel 3x Optical Zoom 5x Digital Zoom 1.8″ LCD Digital Camera 8849366 at

ECEn 391 Lifelong Learning

Lifelong Learning – ECEn 391

James Carroll

I read the paper A High-Throughput Path Metric for Multi-Hop Wireless Routing by Douglas S. J. De Couto, Daniel Aguayo, John Bicket, and Robert Morris of MIT. [PDF PowerPoint Slides PDF Slides].

What I learned

From an engineering perspective, I learned about algorithms that choose what routing path to take in a wireless mesh network. Imagine a network of dozens of wireless devices. In a non-mesh network, all devices receive their network traffic from centralized routers. In a mesh network, however, network traffic flows between all nodes in the network. The sequence of nodes used to transmit a network packet from source to destination is the “route.” This paper focuses on the method used to evaluate routes as better or worse, based on the expected number of transmissions (ETX) required to successfully send the packet. Traditionally, routes are evaluated simply on the number of intervening nodes between source and destination. However, if some links between nodes are fauty (that is, they do not successfully transmit packets 100% of the time), this method produces poor results. The ETX metric provides a significantly better means of evaluating and choosing routes for network traffic. In some cases, the improvement in throughput was a factor of greater than two.

Reading between the lines, I saw a group of students had a great idea, which they pursued without asking themselves if it was possible. They acheived great results and were very successful. Challenges arose, which they met and conquered. Indeed, the solutions to those challenges proved to be significant enough to produce more than one master’s thesis and at least one doctoral distertation.

A few friends had the great idea, “Hey, I wonder if we can get the T1 campus internet connection from home?” They began toying with wireless routers, flashing the BIOS, fiddling here and there, and before long they had a mesh network spanning from the MIT campus to each of their apartments. However, the connection wasn’t ideal. Being the ingenious students, they began to ask why the network was slow, and how to make it faster. This paper addresses such questions, and provides some answers.

From this paper, I learned to question everything. “We’ve always done it this way” isn’t a good reason. Experiment. Try new things and expect the unexpected. Prove it.

My plan to stay current with developments in my field

Last week I joined IEEE, through which I plan to follow the latest developments in the broad field of Electrical Engineering. More specifically, I have subscribed to several RSS feeds, such as “What’s New in Computing” and “What’s New in Wireless”. These monthly periodicals will keep me informed of the latest developments in these two, more specific fields. I know that I am going to graduate school, but I haven’t decided where yet.

If I enter academia, then I will be doing ongoing research in my field, whatever that turns out to be. If I go into law, I will stay current on the latest techical legal issues through quality newspapers such as the New York Times and the Wall Street Journal as well as a professional legal organization. If I go into industry as a computer engineer (the most likely case), I will still be a member of IEEE and will read the professional publications to keep up with developments.