witnie's New Writeups

Audience costs in the terrorist theatre (idea)

2003-07-05T23:43:14Z

Audience? Costs?

Imagine political games on the international political stage, momentum builds up between the two lead players...who will win?
A bit of theory of this, potentailly dangerous, game to understand tensions might help to understand what may, and does, happen in reality, not just when emotions seem to prevail but some 'moves' actually make sense rationally. A useful tool is the concept of audience costs (one of the plethora of game theoretical stuff used in political science). The term was first introduced by Fearon (1994) and describes a situation on the international political stage when a leader of one country backs down in an international crisis with another country. The longer the duration of the crisis, the more 'cost' the leader builds up, where payoff time of these costs depends on behaviour and decisions of the leader. Payment should not be interpreted in monetary terms (although, sure, s/he may lose money), but a measurable extension of loss…

Causes of terrorism (idea)

2003-06-12T00:24:11Z

Research literature on causational factors and diverse goals that drives people to resort to carry out terrorist acts is inconclusive. How these two are connected can be a matter of debate: are researched causes derived from terrorists' manifestos, implicitly or explicitly worded goals, or are living conditions perceived as unjust and not decent and therefore its goals may be inferred, or a mere conjecture?

Ethnicity, nationalism/separatism

Probably the most contested cause of terrorism is an aggrieved group resorting to violence for nationalist or separatist reasons; depending on one's point of view, this can be considered as resistance against an (external) oppressor. Thus far, only Mahatma Ghandi and his followers of the freedom movement have managed to liberate themselves from foreign occupation by peaceful means (Drewermann, 2001), whereas in most other (previously) colonised states "nationalism movements commonly turned to terrorism", it being "the…

synchronous digital hierarchy (thing)

2002-03-24T18:27:28Z

SDH was designed as to be an answer to solve the flaws and problems of its predecessor plesiochronous digital hierarchy (PDH), but SDH itself will be replaced newer technologies and other demands that come about with the evolving internetwork. Therefore, aspects of SDH that could be categorised as strengths may also be a weakness when viewed from emerging technologies.

Summarizing the techonolgy
- Some bytes, called the payload, of pre-defined length are grouped into a container, with each of them getting some overhead information mapping into a virtual container (VC).
- Depending on the size of the VC, the smaller ones are grouped together, aligned, into tributary units (TUs), who are then combined (=multiplexed) to tributary unit groups (TUGs).
- They then are multiplexed into a VC-4, the largest possible virtual container. The largest defined container, being 139264 kbits/s, goes straight into a VC-4 without the aligning and multiplexing.
- The…

iSCSI (idea)

2001-10-23T22:47:29Z

iSCSI is a relatively new and hot item in the IT storage networking technology (at the moment of writing there's nothing more than a internet draft 7). I'm one of the lucky few who is allowed to work with it (ok, some not quite computer-oriented people might disagree with that).
Even though iSCSI is still in diapers with respect to the gory details, the general ideas will be the same.

And why yet another technology?
Besides to keep ourselves busy, it is supposed to make life easier for the systems engineers and administrators. It appeared that systems engineers/administrators didn'r really want to start of building cool Storage Area Networks (SANs) and their managers didn't like the price tags of all that. So to meet these aspects something differentwas created: iSCSI. iSCSI benefits: connectivity, extended distance, media and network attachments (SWANs), interoperability, backup, management, and low costs. Simpler to manage because you can existing…

erythromycin (thing)

2001-01-23T11:19:06Z

Erythromycin binds to the 50S subunit (which is the larger part of a ribosome) and inhibits translocation in prokaryotes.
In other words: this macrolide (meaning: containing a macrocyclic lactone ring) antibiotic prevents bacteria from making proteins by preventing the molecule carrying the aminoacid (tRNA) to connect to the mRNA chain.

chloramphenicol (thing)

2001-01-23T11:17:39Z

This antibiotic originating from the Gram+ actinomycete Streptomyces venezulenza has about the same type of activity as cycloheximide, but than with an effect on prokaryotes instead of eukaryotes: it inhibits the peptidyl transferase activity of the 50S ribosomal subunit (the 50S is the larger half of the ribosome, both parts together translate mRNA+tRNA into the basic chain of aminoacids that make up a protein).
However, archaebacteria couldn't care less about chloramphenicol because of their unique and ancient type of ribosome, wich is different from the "standard" bacteria (eubacteria, the ones mentioned above under prokaryotes).

The genes coding for resistance for chloramphenicol are located on a resistance plasmid (R-plasmid), happily togerther with the genes coding for resistance for antibiotics like streptomycin, tetracycline and a few more. This makes it easier and more efficient for the bacteria to pass on their information about how to combat all those antibitics in the environment.