I use this blog as a soap box to preach (ahem... to talk :-) about subjects that interest me.

Tuesday, September 28, 2010

A message from the FBI?

This post is about somebody impersonating the Director of the FBI on Facebook.

Yesterday, I received the following request from Facebook:

Saturday, September 25, 2010

Australian peculiarities

To start off, I feel I have to explain why I haven’t been posting much lately. I have begun working at an historical novel. The subject is: “The struggle of an Italian sailor to make a family, on the background of his ten years of war, from 1935 to 1945”. It will be based on my father’s life, which was more adventurous than most. And now, to the actual post.

My wife and I like Australia, and have decided to spend the rest of our lives in Canberra, its capital. Of all the places we lived in (Hamburg, Rome, Melbourne, Canberra, Perth, Stuttgart, Zurich, and Paris), and of all the places we visited (London, New York, Washington DC, Sydney, Milan, Venice, and Cairo, to name some), we found that Canberra was for us the best city to settle in. And yet, for central and southern Europeans, Australia has got some peculiarities that require getting used to.

Friday, September 17, 2010

SW processes

At the end of 1998 I became Software Engineering Process Group Leader of the Swiss branch of a large multinational group.  It was my responsibility to ensure that software was developed in accordance with the corporate standard processes.  Some of the developers had very little knowledge of Software Process Improvement (SPI).  To “break them in”, I developed “ab initio” presentations with some basic SPI concepts explained in very simple terms.  I just discovered some of the slides in an almost forgotten folder and, given the fact that:
1.    My presentations were never officially registered in the corporate archives;
2.    the business division I was attached to no longer exists;
3.    more than ten years have passed;
I believe I can share them with you without infringing any copyright.

Monday, September 13, 2010

I am what I am

This is a very short story that I wrote for the Canberra Speculative Fiction Guild.  To be honest, I don't know whether they used it.  I include it here to show that it is possible to write micro-fiction in 124 words.

      When I was first switched on, people often asked me “How does it feel being a robot?”
      My answer was always “When my operational parameters are close to their optimal values, I could say I feel good.”
      They didn’t seem to be entirely satisfied by my answer, and kept asking questions like “Are you happy to be a robot?”
      Bios are very much interested in what they call feelings. Robots are not. When I do what I have been built to do, the potentials in my positronic brain are in balance. Whether this condition could be called happiness is irrelevant.
      Now that they have become used to me, the bios have stopped wasting time with useless questions. It is better so.

Wednesday, September 8, 2010

Photovoltaic Panels

Advertisements for solar panels have begun appearing on Australian television. At least, they have become frequent enough that I noticed them. Obviously, the purpose of the ads is to encourage the viewer to buy solar panels, but they tend to be misleading. By selling the electricity you generate, you eventually repay the acquisition price of the photovoltaic system. That’s true. It is also true that your electricity bill is reduced and can even go negative (which means that you get money from the utility). But you shouldn’t consider the two facts simultaneously true. After all, the utility pays you only once!

In this post, I will describe what I think is the financially correct way to look at the photovoltaic panels. But to start, I will first tell you what system my wife and I have bought.

We have on the roof eighteen panels manufactured by Sharp (model NT-N5E3E), as shown in Figure 1.
Figure 1: Our panels.

Each panel can nominally generate up to 175 W of power. Therefore, our maximum generating capacity is 3,150 W.

Monday, September 6, 2010

OO - UML Behavior Diagrams

This is the last post on Object-Oriented Technology. I know, there is so much that remains unsaid... Perhaps one day I’ll write more about it. But don’t hold your breath!

Behavior Diagrams
There are six different types of behaviour diagrams. They are: activity diagrams, state machine diagrams, use case diagrams, communication diagrams, interaction overview diagrams, sequence diagrams, and UML timing diagrams. The last four are also collectively called interaction diagrams because they concentrate on control and data flow among the system components.

Sunday, September 5, 2010

OO - UML Structure Diagrams

In the previous post, I described a basic method suitable for designing simple OO applications. Obviously, as the applications grow in complexity and the teams grow in size, making lists of properties and methods quickly becomes insufficient to support the development process.

A widely used (and very powerful) software development process is the Unified Process, of which IBM's RUP (Rational Unified Process) is currently the best example. But describing RUP would be too much.

What I can do is to introduce you to a formalised and standardised way of describing OO systems, suitable for applications of any complexity and with all possible development processes. This is the Unified Modeling(1) Language (UML).

Saturday, September 4, 2010

OO Development

A lot has been written about how to develop software. In this post I want to summarise the basic concepts. That is, those concepts that many drown in rivers of jargon and buzz-words.

Friday, September 3, 2010

OO basics and Java

In relative terms, some classes are very general, others very specialised. We use the term subclass to indicate a class which is a more specialised version of another class. For example, the class Convertible is a subclass of the class Car, because a convertible is a special type of car. The reverse is obviously not true, because not all cars have a retracting or folding roof. It would be incorrect to say for example that the class Bike is a subclass of Car, although both are subclasses of Vehicle.

Thursday, September 2, 2010

OO does it with Class[es]

This post begins a small series of postings on Object Oriented Technology.

In our everyday's life, we deal with objects all the time. Some are so small that they fit in the palm of our hand, and some are so large that we can walk into them and then even get lost in their interior.
In its basic meaning, an object is a material thing that falls under our senses. Notwithstanding the obviousness of this definition, objects have revolutionised the way in which we write computer programs.