Technical article vs. research paper Being a professional software engineer, i have seen a lot of really interesting technical work, many of it is published as technical articles in technical journals and websites like http://www.drdobbs.com and http://www.codeproject.com and many others, here is a few examples in some areas of interest:

Algorithm engineering and implementation:


http://www.codeproject.com/Articles/18113/KD-Tree-Searching-in-N-dimensions-Part-I
http://www.codeproject.com/Articles/9021/Simple-and-fast-Huffman-coding
http://www.drdobbs.com/cpp/sorting-an-immutable-list/240163397
http://www.codeproject.com/Articles/33781/Calculate-Percentiles-in-O-1-space-and-O-n-time


Data structures:


http://www.codeproject.com/Articles/43103/SlimList
http://www.codeproject.com/Articles/2839/C-AVL-Tree-Template
http://www.codeproject.com/Articles/9138/Fast-Binary-Tree-Operations
http://www.codeproject.com/Articles/23198/C-String-Toolkit-StrTk-Tokenizer
http://www.codeproject.com/Articles/11274/Implementing-a-memory-efficient-search-tree-for-a


Text search:


http://www.codeproject.com/Articles/198236/Boolean-text-search-queries-and-their-processing
http://www.codeproject.com/Articles/20423/N-gram-and-Fast-Pattern-Extraction-Algorithm


Object oriented and generic programming:


http://www.codeproject.com/Articles/16006/Dynamic-Inheritance
http://www.codeproject.com/Articles/19444/Interface-Detection
http://www.codeproject.com/Articles/20085/Superior-container-classes-Smaller-faster-flexible
http://www.drdobbs.com/cpp/theory-versus-practice-the-great-divide/240160938


Database optimization:


http://www.codeproject.com/Articles/25728/Database-Virtual-Cursor


Real time processing:


http://www.codeproject.com/Articles/224733/Shared-Queue


This level of work is considered highly innovative from the technical/engineering point of view.

I wonder if any technical work can be considered an academic achievement and can be deployed in research papers as well as technical articles.

In other words:
When can a technical article be published as a research paper, in which areas? any examples?

Thanks
Thanks for the question; I had similar questions few years ago, before starting in research (I'm not necessarily assuming that's your case).

I've looked at a couple of the links, and they don't really look like research papers in form; I mostly can't really tell if their technical content could be made into a paper because I'm not an expert in the field, but I'm guessing "no". If you compare your links to a paper, you'll notice several differences. But highlighting them and their rationale might help.

The key concepts are:


Scientists learn new knowledge for humankind, and then share what they learn through research papers.
Moreover, we live in information overload, so readers only have time for the most important knowledge.


As a consequence, research papers have some key features.


A research paper contributes new knowledge in a field (novelty). To convince readers of this new information, it provides appropriate evidence to argue for it. What's appropriate evidence varies depending on the field and on what the paper claims.
In fact, since a paper must be novel, it must also argue that its content is novel (though that's done somewhat implicitly). That's done by comparing to related works in the field; if another work looks similar to a submission, the author must explain what's the novelty in his work. Moreover, no paper is entirely novel, so a paper must also say what was already known by citing its invention (except for things that are standard). As a rule, technical articles don't do that; they typically don't claim to be novel. Sometimes the author invented the technique by himself, but it was already known.
Good call for papers mention the criteria for judging papers — this one mentions novelty, importance, evidence and clarity.
A good research paper should also contribute knowledge that is "interesting", and explain it clearly to the reader. What's interesting varies according to the publication venue.
In fact, my favorite intro to research in book form is The craft of research, though what I've read is parts of this condensed version. I'd recommend to start reading it from the Amazon preview.


Example

The above is not really specific to computer science, so let's have an example.
Since most of your examples are in algorithms, I'll try to show what the above means for an algorithm paper (even though I'm not an expert in that area, so I hope I won't get it too wrong). Such a paper might claim that some algorithm is fast, and prove that through complexity analysis or experiments. That paper better claim that the algorithm computes something useful (otherwise, who cares that it's fast?), often because it's correct; appropriate evidence is then a correctness proof. Moreover, this algorithm probably reuses ideas already known to experts (which should be cited), but has some key differences from any similar works (which should also be cited) — maybe it has the same complexity but is more general, or is simpler to implement, or has any other virtues that experts have agreed are interesting.

By contrast, a paper on, say, programming languages would have different claims and different evidence, but would still follow the same basic structure.