A while ago I posted a link to MIT's Open Courseware (OCW) site. Recently I have begun to make use of it and wanted to share some of what I have found. First of all, it rocks! It really is a great resource, especially for those who want to learn about a subject and would like to do self study. I didn’t realize this earlier but a number of the courses also publish videos of the lectures. For example 3.091, "Introduction to Solid State Chemistry" has all 35 lectures posted, thats almost 30 hours of lecture time! These videos (If available) can be found possibly in 3 locations, so keep that in mind. The first is on the OCW site. Browse to the course you are interested in, for example Introduction to Solid State Chemistry. Under the "Lecture Notes" (This label may be a little different between courses) section you will find the video streams and the lecture notes. The second location is on the regular class page. 3.091 has a tab called "Videos" and another called "Archives", both have links to lecture videos and notes. Now the third place you can check, if you want to easily download the videos, is Google Video. Searching for "3.091" brings up all but 2 of the course videos which can be downloaded in in a format that can be played by your video IPod. Actually Google Video has over 450 MIT Lectures available for download! There are also nearly 300 UC Berkeley lectures as well. If you want to download any of the lecture videos (to your hard disk) that are offered as a stream on the MIT website you can use a program like FlashGet to save the stream as a file and then convert the file to what you want. The MIT site publishes RealVideo streams (That use the RTSP protocol).

Other courses that offer video lectures are (To name a few):

Physics - Electricity and Magnetism
Physics - Vibrations and Waves
Physics - Classical Mechanics
Physics - General Relativity
Mathematics - Differential Equations
Mathematics - Linear Algebra
Chemistry - Principles of Chemical Science
Chemistry - Solid Sate Chemistry
Biology - Introductory Biology
Computer System Engineering
Circuits and Electronics
Atomistic Computer Modeling of Materials
Media, Education, and the Marketplace
Electromagnetics and Applications

You may want to look on the course listing to see if there is a newer version of the course as newer ones are periodically added.

The OCW site also offers the course syllabus, study materials, readings, exams and a number of other resources. They offer the option to download the entire course as a zip file so that you don’t have to download the resources individually.

Now a few words about the "Introduction to Solid State Chemistry" (3.091) course... If you are interested in learning about chemistry I would highly recommend the 3.091 course. Donald Sadoway is the lecturer for this course and he does an amazing job! You can tell he loves the subject and he knows it very well. He has a great sense of humor and he really makes the material come alive (At least for me anyways). This course lays an excellent foundation for other areas of study.

Many times when we think of OSS we think "cost savings" or “free”... Not so. There are many hidden costs that accompany the integration of OSS into your infrastructure. I’m currently in the process of integrating some OSS into our infrastructure and am really seeing this. Now don’t get me wrong I’m a big fan (and user) of OSS but it’s important to see the big picture when making decisions and planning projects that involve OSS.

One of the hidden costs is learning and configuring. OSS, from what I have seen, seems to be seriously lacking when it comes to ease of use and configurability. Many times OSS is command line based, configuration is in INI style config files. It takes time to read through documentation (Which may be sparse in some cases). I have also found that actually playing around with the app and configuration is in some cases the best way to figure out how to configure and use the software. Again, all of this takes time. On the other hand the pretty app that you pay for will (If it’s any good) have an intelligent installer, very intuitive GUI, and lots of support and documentation. I recently had an experience where I setup one of those “pretty, paid for” apps and I literally had it up and running and configured in a couple of hours. I was totally blown away! If it were OSS it would more than likely taken me a couple of days (Or more) to get in there and figure it out.

Another hidden cost I have seen is maintenance… Many OSS software packages have cryptic or crud management and/or maintenance interfaces. These can be cumbersome and time consuming to work with and can be difficult to get others up to speed on using them. This may also lead to neglect because it’s a pain to work with or others don’t feel they have the time to learn it. The app that you pay for (If it’s any good) will probably have a slick interface to maintain and administer.

Again, I’m not knocking OSS, I think OS development is a wonderful thing. There are a lot of awesome OS projects out there. I also think that OSS fills an important roll in any infrastructure. But when you decide to go the OSS route you can’t be in the mindset that because it’s OS it’s free. You really have to think about the pros and cons and make a decision based on that. In some cases it may actually be cheaper (And more advantageous) to buy instead of going the OSS route.

As a side note, I have heard some balk at “pretty, paid for” apps for various reasons, some valid some not objective at all. But the reality is this: Those days as a single guy staying up all night eating Doritos, drinking Mt Dew and hacking on all kinds of interesting stuff are over. In the real world you have a family, deadlines and clients (both internal and external). Time is really of the essence and you dont have much of it. Your boss or your wife and kids aren’t going to be impressed because you worked OT for 2 weeks learning how to wiz around some cryptic OSS like Kevin Mitnick phreaking a telco switch. The time spent getting to that point may not be worth it or you may not even have it. In many cases “pretty, paid for” equate to steep learning curve, ease of use and maintenance and good support. They also may mean less stress and more time for life’s more important things. It really comes down to making a good business decision that will help your business to succeed, not a decision based on ego that makes you think your The Brain.

I recently had the opportunity to work with a 2d area scanner (aka Bar Code Reader) in a .NET application. Previously our client used proprietary software that just plain stunk so we decided to write our own software. One very cool thing I discovered while working on this project was that many USB devices (Like bar code scanners, joysticks, game pads, mice, keyboards, etc) sport a Human Interface Device (HID) interface. This interface communicates using the standard HID protocol defined by the USB Implementers Forum. The cool thing about this is that one standard device driver can be written and used for all USB HID devices on a particular platform. Normally you would have to write your own device driver or use an existing one to communicate with a USB device, ouch! USB HID eliminates that requirement. Windows ships with a standard USB HID device driver and automatically makes the HID interface available when a USB HID device is plugged into the system. Nothing to install, no device driver to write, yay! Windows also has a fairly easy to use API (Although a little quirky) for communicating with HID devices. This site, run by Jan Axelson, has a lot of good information on communicating with USB HID devices. His book, USB Complete, is also an invaluable resource, I would definitely recommend it if you will be doing HID development on any platform.

I have an HID .NET library available here if you want to skip most of the gory details and get right down to business. I have used this library in production and have not had any issues, please let me know if you have any feedback. Using this library, while encapsulating most of the underlying details, will require you to understand the format of data contained in the payload of the reports sent to and from the device. HID’s communicate using "reports" which are analogous to packets in network terminology. The reports themselves are a standard USB HID data structure although the payload of these reports will be specific to the device or device type. Usually the payload data format can be found in the device SDK and/or by simply analyzing the payload data the device sends.

The following library, developed for the HHP IT4600/IT4800 area scanner, uses the aforementioned HID library.

Have you ever wanted to embed an HTTP server into your application? For example let’s say you have a Windows service that you want to administer or monitor (Google desktop is a good example of this). Or let’s say you have an application that requires an alternate interface such a kiosk application. Wouldn’t it be great to have an embedded HTTP server that would allow you to provide a web interface for your application without requiring IIS and without requiring you to write a web server? If so then Lomez is your friend!

Lomez is an in-process HTTP server that allows you to create virtual directories, serve static content from a file or embedded resource and expose any object by implementing the HTTPHandler interface. It loosely resembles ASP.NET to allow you to use it with ease.

Ok, enough of the spiel… Basically I have a number of applications I work with that I would love to have HTTP access to, especially Windows services. I have looked high and low but have not found a library to allow me to do this. So at that point I figured I would have to develop something myself and Lomez was born. I have successfully used this library in a production kiosk framework (At 2 tradeshows so far) and it has worked like a champ. The current version of the library can be found here. I would love to hear any feedback you might have on it.

I consider the current version more of a proof of concept and would really like to rewrite it from the ground up. So hopefully I can begin doing that soon. I would really like to include basic authentication, challenge/response and SSL in the next version. I would also like to optimize the HTTP pipeline so it is lean -n- mean. It’s definitely not right now.

Anyways, if you end up on this page because you are looking for an in-process HTTP server for .NET please let me know your thoughts. And if you decide to use the library, let me know what you think of it.

Thanks!

The Management

The library found here allows you to obtain the physical coordinates of a zip code. This can be useful when dealing with weather or map related services that require a latitude and longitude as input but where the user would be providing a zip code. This small library (With a footprint of about 650k) contains the zip code to coordinate mapping as a binary resource embedded in the DLL, so no additional files or interaction with a web service is required. The data contained in the library was obtained through the US Census Bureau and is current as of the year 2000. If a zip code is not contained in the data the nearest match is returned.