Feeds:
Posts
Comments

Archive for February, 2012

I (heart) Malaga

Photobucket

I don’t know why, but I just love Spain. I love the hot climate, the awesome countryside, ranging from wild mountains and deserts to lush forest and the beautiful Medditerranean and Atlantic coasts. One of the cities I love most is Malaga. Malaga is in Andalusia, right on the Medditerranean Sea. But lo and behold, it is not a tourist trap, this ancient city! Once ruled by Phonecians, Romans, Arabs and finally the Spaniards, the city looks and feels like a mix of different styles of architecture and cultures. The weight of its history is prevailing in almost every corner. It was also birthplace and home to the one and only Picasso. The city is well aware of its heritage, as there are several historic museums, one Picasso museum and the house of his birth.

So loaded up, we first went to our resting place ( camping site), that was about 20 minutes from the center of Malaga and not that expensive at all. What I did not expect of Spain before actually going there was how well its infrastructure is developed. There is very cheap train service everywhere and busses are even cheaper!

Photobucket

Going on a tour at our new “home”, we discovered an awesome beach (unfortunately no photo), with palm trees next to it. I love palm trees!

Photobucket

When we finally made it to Malaga (not because it is so far, but because we were very busy discovering our locality), it was already night. I don’t know what is more impressive, Malaga at night or Malaga at day, but I have to say both are pretty freaking impressive!

Photobucket

Photobucket

Another great thing about Spain is the food. The cuisine is of high quality and very tasty, and it is not even that expensive. Tapas are great for every opportunity and paellas are just tasty!

Photobucket

Of course, we are missing something here, or are we? No, because the Turkish Donerman is everywhere!

Photobucket

And once you are done with sightseeing, you can go get your culture fix (or take a picture in front of a museum to tell your parents you educate yourself), visiting one of the many museums or historic churches.

Photobucket

Photobucket

I like the architecture of the buildings in the city center, the city council seems to be doing a good job maintaining everything.

Photobucket

Photobucket

And for some relaxation there are plenty of little parks scattered throughout the city.

Photobucket

Photobucket

Advertisements

Read Full Post »

Photobucket

Image: healingdream / FreeDigitalPhotos.net

We all have this problem. We want to finish a job, we have to do something, but we just cannot get around. We might get distracted very easily, or just look for an excuse not to do our work. But why do we procrastinate? Let’s take a look!

The Reward

A lot of times procrastination is rewarding. You know the situation, a tough decision has to be made, and you are the one who has to make it. But you don’t know what to do. You wait and you wait, claiming you need more time or some other lame excuse, until it is too late to make a decision, the decision has been made for you, or the situation has totally changed, allowing an easier decision to be made.

Resentment

Sometimes procrastination is the only possible way of showing resentment or disagreement. One might be forced to comply with a boss, or have to do some “stupid” homework for a professor. Open “rebellion” or disagreement might not be possible (or you just don’t have the balls…). So we resort to procrastination! Everybody has experienced this type of procrastination, like when preparing for an exams that seemed not to be of value.

Fear of Failure

We are our own worst critic. Usually, we expect way more of ourselves than we do of others and than others do of us. Sometimes we don’t want to disappoint others around us. Whatever it is, we are scared of failing. This fear leads to procrastination, sometimes in the hope that the situation will disappear by itself, and sometimes it is so crippling that it leads to the cancellation of the whole job/project.

Fear of Success

Ironically enough, people fear success as much as they fear failure. Success means that people will be expecting this kind of performance more often and will judge you by this success. It means higher and higher expectations. Many people are scared of that, so they sabotage their success by procrastinating. Other times success puts you into a new environment (like a promotion), and now you are the underdog, the newcomer, you have to prove yourself once more.

The Mountain

The first moments of tackling what seems to be a big project or a huge task are very scary. The job looks like a mountain, impossible to pass. Sometimes just thinking about the amount of work that has to be done makes people dizzy! So again we procrastinate, because we don’t know what to do and we feel overwhelmed. We don’t realize that as long as we keep starting, as long as we keep taking small baby steps, things will eventually come to a finish, and once monumental tasks will seem like baby games.

More Info

I have experienced all the aforementioned reasons for procrastination. But on my quest to lead a more productive and stress-free life I wasn’t alone. The market is basically overflooding with self-help literature of self-proclaimed experts (who most of the time are not experts at all), so it is very hard to find books that actually have some essence. Fortunately, not all this self-help stuff is voodoo-boggus! Neil Fiore, Ph.D. has identified many hidden reasons why people procrastinate and gives valuable tips on how to avoid procrastination and overpower the urge, in his book The Now Habit. Contrary to most ot the literature out there, he does not give stupid and superficial tips (“Make a list and prioritize”…duh, I know that, if it worked I’d be doing it, right?), he goes to the root of the problem. Check it out, it’s well worth a read!

Read Full Post »

Photobucket

Welcome everybody to our new series, “Dissecting the X”. In this series, we will take a closer look at different types of airplanes, be it military or civil. We will discuss the characteristics of this type of airplane, what makes it special and different in regards to aerodynamics, mission and equipment. I will try to be thorough but not lost in the detail, so you can get an overview of how each component plays its role as part of the airplane. At the end of each post I’d appreciate it if you could leave a little comment, telling me what you liked or didn’t like, and which airplane you’d like to see next time.

We’ll start this series with the F-15. The McDonell Douglas F-15 Eagle entered service in 1976 and has been in service since. It is expected to stay in service well beyond 2025. This has several reasons. First of all, the F-15 airframe is a true powerhouse. It has been very well designed and several service updates have kept it…well, up to date. It can stil compete with newer generation aircraft, like the Eurofighter (the Eurofighter has the advantage though, as it is a newer design). Another reason is the fact that due to current budget restraints the US government (the main operator of the F-15) cannot afford to field a large number of more modern aircraft (like the F-22) and therefore has to rely on the F-15.
The following video is a pretty impressive proof of the F-15’s capabilities.

Let me recap this: the F-115 in this video flew with only one wing! The other one was missing, it was torn off during a maneuver accident! Now, how could the F-15 do that? Let’s find out!

Fuslage – The F-15 has a very thin fuselage (compared to other aircraft) that also generates lift. See, a special form is not the only way of generating lift for a body. If you stick your hand out of the window of a car in motion and there is an angle between your hand and the wind, you will feel a lifting force on your hand. The same goes with all kinds of bodies. Even a flat board will generate lift if it has been angled relative to the wind. Now, why go through all the trouble of manufacturing and designing wings, if flat boards would do the job, too, you might ask. A relevant question. The reason for the use of special wing “forms” (called wing sections), is the fact that the bigger the angle gets, the harder it is for the air to follow the board. Eventually the flow seperates from the surface of the board, which leads to a dead area downstream of the seperation point and leads to lower lift, and higher drag (the force acting in the opposite direction of motion…which means drag is bad!).
The F-15 has a high wing configuration. One advantage is that a shorter landing gear can be used. But the flow over the wing can also negatively influence the vertical stabilizers, as there is not the fuselage inbetween to prevent this.

Photobucket

Control Augmentation System (CAS) – When the F-15 was designed, fly-by-wire technology (that is, electronic controls) were not in use. In fact, the F-16 was the first aircraft that relied solely on fly-by-wire. So at first the F-15 had mechanical control systems. Later it was upgraded with a so called Control Augmentation System (CAS). The CAS is an electronic control system that translates and coordinates the inputs of the pilot to achieve superb performance. The mechanical systems were still kept in the F-15, so it could still be flown in case the system went inoperable. How could this have contributed to flying the F-15 with only one wing? Well, the CAS saw that something was wrong with the missing wing (it was missing) and translated all the control inputs of the pilot in such a way that the airplane could still be flown.

Wing Configuration – The F-15 has a swept back wing, that somehow resembles a delta wing. To enable to F-15 to fly several times the speed of sounds without producing exessive drag, the sweep angle of the leading edge is very important. Also notice the big wing area of the F-15. The lift a wing can create is directly related to its’ wing area, the bigger the area, the more lift can be generated at a given speed. A high wing area means the F-15 can fly at lower speeds and have a smaller turn radius when maneuvering, which is very important for fighter planes.

Empennage – The empennage of an airplane is the sum of its vertical and horizontal stabilizers. As a fighter airplane, the F-15’s empennage needs to be as light as possible, but still generate enough force to make the F-15 highly dangerous in aerial combat. A big problem especially fighter planes have is the integration of the empennage and the engines with the fuselage (the body of the airplane) in such a way that the different parts influence each other as minimal as possible. The F-15 is a good example of this integration.
It has two vertical stabilizers as a result of this integration. Two vertical stabilizers mean that the area of each one can be smaller than the area of a single vertical stabilizer. That also means that each one of those two stabilizers doesn’t have to endure as much force as a single one and can therefore be built lighter. Everything has its drawbacks though. Two stabilizers means more interference between the different parts of the empennage and higher drag! An important thing to understand in aerospace engineering is the fact that it basically is a big game of trade-offs. There is nothing one can get without having to give up something else!

Photobucket

The F-15’s horizontal stabilizers are all-moving. This gives the pilot more control over the aircraft, but it also means heavier and more complicated controls. An interesting thing to remark about the F-15’s horizontal stabilizer is the distinct sawtooth on the leading edge. This sawtooth is supposed to generate extra lift via vortices. It is usually used when late in the design phase experiments and calculations show that the body is not generating enough force, but a total redesign would be too expensive. It is sort of a quick and dirty fix.

Photobucket

Photobucket

Variable geometry intake – The F-15 is supposed to fly at a speed higher than twice the speed of sound, which makes every aspect of its design more complicated. Everything has to be custom tailored for these special situations. For that reason the air intakes for the two turbines have variable geometry, to adapt to the changing conditions of supersonic flight. (In the following picture you can see the intake of the F-14, but the F-15’s intakes look pretty similar.)

Photobucket

The intakes are positioned on the shoulders of the airplane. This is kind of unfortunate, because positioning the intakes under the center of the airplane leads to a better airflow into the intake at all angles of attack, in contrast to the position chosen for the F-15. Wind tunnel experiments and CFD calculations have shown that the two intakes, if centered side by side under the center of the fuselage would influence each other in an unacceptable way.

Photobucket

Mission – The F-15 is a tactical fighter and was mainly designed to gain and mantain air superiority. Air superiority basically means controlling ones own aerial territory and having a distincting advantage over the opposing air force. So the F-15 was basically designed for air-to-air combat (also called dogfight). How do all the different components fit into this? Well, the powerful engines allow a very high thrust-to-weight ratio, that allows the F-15 to have a very high acceleration. Combined with the variable geometry air intakes, this allows the F-15 to reach supersonic speed. The big wing area and low wing loading (the ratio of the wing area to the weight of the aircraft) give it superb maneuverability and a small turn radius, which allows the F-15 to easily turn into an enemy airplanes turn.

Little Copyright Info:
Some of the pictures were taken by members of the US Armed Forces while on duty, so they are in the public domain. One schematic was taken from wwwf-15e.info, they have all the rights to that schematic. All other schematics were taken from Klaus Hünecke’s book “Modern Combat Aircraft Design”. I do not own those copyrights!

Read Full Post »

Lake Bafa

Mass tourism might work for some. But it’s not really my cup of tea. I don’t like to visit crowded, overrated and overpriced places, full with tourists, their cameras and their…peculiar behaviour. To really discover a country, one must go off the commonly known roads. Visit the land and the people.

And off the road we went! During our tour of the Turkish west coast we discovered hidden gem after hidden gem. One of these gems was Lake Bafa.

Lake Bafa is on the eastern coast of Turkey, about 2 hours from Izmir, and 1 hour from Aydin. Hidden between mountains, forrests, and little Turkish villages, it is still untouched by industrialization and tourism. The road leading up to the lake is easy to find, but the closer one gets, the more off road one has to go. We actually missed the direct road to the lake and went to a closeby village and a road hugging a mountain and overlooking the lake. The sign leading to the lake looked like out of an old western movie, so of course we missed it and went the other way around the lake.

Tugged between mountains, surrounded by forrests, many little Turkish villages are around Lake Bafa. Unfortunately nobody on the Turkish countryside speaks English, but if you know even a few words of Turkish, those villagers will love you. If you have the opportunity to make friends with them, do it, because those will be some of the nicest and most gentle people you have ever met!

Photobucket

When we finally got to the lake, we were welcome by Turkish fisherboats. For some of the people living in the area fishing is the only way with which they can support their families. The landscape, the heat and the boats reminded me of an Indiana Jones movie so bad!

Photobucket

Lake Bafa is a huge lake and national conservation site, with thousands of rare species forming a unique eco system. Surprisingly, it has not been discovered by many tourists. On the main (asphalted) road around the lake are several little restaurants and villages. All villages have little cafes with awesome local food for very economic prices.

Photobucket

We drove up a road hugging a nearby mountain, it was kind of bumpy but nothing our little jeep couldn’t handle. To our left and right the mountain got really steep as we were climbing up the road, revealing a marvelous view onto the lake.

Photobucket

The trouble was worth it. We were seeing stone formations to our left and our right, and in front of us was great Lake Bafa. This is how pioneers and adventurers must have felt!

Photobucket

Photobucket

On our way back we were surprised by a heard of mountain cows! At first there were just a few. As you can see, they are rather skinny. No wonder looking at the “lush” veggetation all around.

Photobucket

But they got more and more! For a second or two we were scared the cows wanted to eat us and overtake the world…but we realized that only happens in bad horror movies or equally bad parodies.

Photobucket

After this unplanned hike into the woods, we also got a look at Lake Bafa from a more…fortified position.

Photobucket

After enjoying a few teas and a great meal at one of the villages around Lake Bafa, we called  it a day and headed home.

Read Full Post »

When you are new to programming and want to start learning, it is very hard to find a good introductory book. Most books are either too simple, just teaching a few routines, and not the underlying way of how to think as a programmer. Others are way too complicated and abstract, bombarding the reader with hard-to-grasp concepts. Common Lisp: A Gentle Introduction to Symbolic Programming by David S. Touretzky is a nice little exception to that rule. Mr. Touretzky is a researcher at Carnegie Mellon University and a champion of free speech, and it is reflected in his book: even though it was published in the 90s it is available for free and legally on the internet.

Lisp is an old programming language, that has some unique characteristics and will be very different at first look. It has a unique style, that will make you fall in love with it. You can read more about Lisp

Common Lisp begins with a gentle introduction into programming in general and Lisp in particular. The difference between functions and data, number types and some basic programming concepts are explained. He then moves on to explain lists, the basic building blocks of Lisp. The relationship between lists and  elements of lists is explained in a very clear and concise manner. Some basic list operations are introduced. After explaining the eval notation, a special type of notation to describe Lisp functions, Touretzky then moves on to explain conditionals, like the if- and when- functions. Before you know it, you can do some pretty crazy things with Lisp, and this is just the beginning! Chapter 5 is all about variables, their scopes and their effects.

All in all, there are 14 chapters, totaling more than 500 pages. Every chapter is divided into an introductory section, which explains new functions and gives examples, exercises which really enforce what has just been learnt, and an advanced topics section. Solutions for the exercises are not given, which some might see as a drawback, but I think it is really well thought out like that! Because when you are working on real world problems you don’t have the solutions at the end of the book. You have to find your own ways to make things work, and this book does a great job in forcing you to think hard!

Read Full Post »

6 tips for traveling Turkey

Photobucket

Even though Turkey is a beautiful country with a great landscape, a rich culture and probably the best hosts in the world, it gets overlooked a lot of times. Most of the time it is identified with off the shelf, boring tour travel.
But it can be more than that! Discover how you can get the best out of your trip

1) Be careful with your flight
Good care must be taken for the planing of the flight. Depending on from where you want to fly in, tickets can be very cheap. Berlin has a huge Turkish community (the biggest in the world, to be precise) so there are several flights to and from Turkey every day, and they are rather cheap. Other major German cities are not as blessed, but compared to other countries you can still get a good deal. The picture is, of course, different in other countries. For example, going to or coming from France is substantially more expensive.

Photobucket

At the end it really depends on how thorough you search and a little bit of luck. Use all the major search engines to find the best flight for yourself.
A word of caution: try flying with Turkish Airways if you can. They have the best service, airplanes in good shape and great pilots, a lot of them former air force officers. They are a little more expensive, but they are a star alliance member, so you can earn points if you have a frequent flyer card.

2) Plan your transportation
If you are from Europe or America, Turkey is a really cheap country. It has a good transportation system between cities that is also very cheap, but there is one problem. Information is a scarce resource in Turkey. In cities it is really hard to find out which bus goes where! There are no printed plans on bus stations and the guys sitting in the tourist office have no idea. The best way is to ask around. And who needs buses anyway? It is was cooler to walk around, you get to see a lot more! When I was in Istanbul the last time I was constantly walking, discovering new sights and just enjoying the city.
If you want to stay in the city where your plane lands, try to find out how to get to your place from the main bus station of the city. At the airport there are always little buses (called Havas) that go to the main bus station and sometimes they even stop at the major places of the city. No need for a taxi! If you are staying out of town there are buses to all major cities and if you don’t arrive at an odd time, like 3 in the morning, you will find a bus. Try getting on one of Metro’s buses, their service is the best and their buses are the most comfortable.
To go to small towns and little villages in the area you can hop on one of Turkey’s famous Dolmus. Dolmus means” full” in Turkish, which is a very fitting name because the driver takes as many people as he can. These Dolmus are small buses that offer very cheap fares between cities. You can get on and off wherever you want. Don’t be scared, they might look old and worn and a little bit unsafe, but accidents involving Dolmus are very rare.

Photobucket

3) Ask questions
You will find out that Turkey has some of the nicest people around. They love foreigners that come to discover their country, and they will love to help you and give you directions. Don’t be afraid to ask questions! The older generations don’t know any English though, so if you are not willing to learn a few words and phrases you will have a hard time communicating. If you ask locals what sights are around that are worth visiting, you will get to know a ton of locations that are not crowded by tourists. When we went to rent a car we asked about cool places in the area and ended up visiting two ancient Greek settlings (Priene and Millet) that were devoid of tourists (compare this to Ephesus where you can’t walk without stepping on a tourist) and an awesome Natural Park (Lake Bafa) with literally no person around! Don’t be afraid, ask questions!

Photobucket

4) Be careful with alcohol
This is an important one. Every year many tourists get alcohol poisoning and every few years people die because of this! Do NOT, I repeat, NOT drink alcohol of whichs origin you are not sure! The tax for alcohol is very high in Turkey, so there is a high demand for illegally produced (and therefore cheaper) liquor. Sometimes restaurants and tour operators are so greedy they take the risk.
Whenever you buy alcohol, check if the bottle has not been opened and there is a security holograph. Avoid drinking alcohol when you go on boat tours and in restaurants. Play safe.

5) Don’t get ripped off
Like in every touristic and poor country (compared to central Europe), people will try to rip you off. Turkey has some of the nicest, and some of the worst people. Always be cautious and use common sense. Don’t get in cars of people you don’t know, if you are a woman try not to go in bars or cars where there are only men.
If you want to buy something anywhere except a supermarket, don’t pay the price they tell you. Vendors always have a trade margin, and since they see you are foreign they will double (and sometimes even triple!) the price. So you wanna buy something? Good, find out how much it really costs, do some research and try to talk the guy down! Your first offer should always be half or third of the first offer of the vendor. Be hard, and be ready to walk away! You will find it somewhere else, and you can use your first encouter as a leverage to get a better price.

Photobucket

6) Watch your stuff

Touristic places everywhere around the world are unfortunately filled with scum…people who will try to still your stuff. Carry your important belongings on your body, always have an eye on your backpack and luggage and treat other people with a grain of common sense and suspicion.

Photobucket

Read Full Post »

Now, negative G’s are o fun. If you pull too many negative G’s, you might red out because all the blood in your body shoots into your brain and eyes, which could cause blood vessels in your head and eyes to explode.

But sometimes they can be funny, too. Check out the video below.

Negative G’s

Read Full Post »

Older Posts »