Is it necessary to show what improvements you have made to similar work in literature reviews section? I have seen quite a few research publications where the literature review section doesn't compare past work to the author's work. It's like:


  [1] did this using X technique. [5] used Y technology. (etc.)


This type of literature reviews are easier to write as I don't have to read similar works in extreme detail to create a list of things that we are doing and they are not. I can understand their technique by reading their abstract but it won't matter too much as long as I am using a completely different technology.

I have also seen some good publications which compare each and every work in literature review section to their own work and say "They did not do this", "Their work couldn't do that". While, of course, this looks a lot better but it's a lot harder to write.

Let's say I using queuing theory for a similar work which has been done using some other technique. I can easily state that they used this technique in their work instead of trying to find drawbacks in their work.

So which approach is better when writing the literature review section?
Contrasting your work with earlier work on the same topic (same or related questions) is a crucial part of a scientific publication. You have to explain to the reader what makes your approach better (or worse) depending on the exact problem to solve.

Now, whether you should do this in the section devoted to review of the existing literature is debatable. There are no strict rules, so as long as you do it somewhere and the paper is clearly readable, just do what seems best to you. If you have trouble writing, I would suggest you separate the content into a simpler form:


State of the art: review of the existing literature. What problems are solved, what are remaining questions, where can we make progress. This is the motivation of your work.
Your methodology
Your results
Discussion of how these results compare to earlier work: you're doing better than A and B on large matrices, but the approach means that you will be slower than C on sparse matrices, that sort of stuff.