Good week this week, started quite good on Monday with 4,5 km running and then pretty much nothing until Sunday for another 4,4 km. Not very well disposed this week but there has been lots to do and I have gotten home tired and out of what. Better next week!
Day by day
Running 4,5 km – from home via Slammertorp rd then on the illuminated track and back through the center, good round.
4,4 km in Altorp with Jenny. I felt like crap, the running was bad, the trail however was great so I hope to do it a few more times before the snow sets in, and the company was splendid as always. Love to run with Jenny, it is something I always look forward to.
Personal observations on the reliability of the Shuttle
by R.P. Feynman
It appears that there are enormous differences of opinion as to the probability of a failure with loss of vehicle and of human life. The estimates range from roughly 1 in 100 to 1 in 100,000. The higher figures come from the working engineers, and the very low figures from management. What are the causes and consequences of this lack of agreement? Since 1 part in 100,000 would imply that one could put a Shuttle up each day for 300 years expecting to lose only one, we could properly ask ”What is the cause of management’s fantastic faith in the machinery?”We have also found that certification criteria used in Flight Readiness Reviews often develop a gradually decreasing strictness. The argument that the same risk was flown before without failure is often accepted as an argument for the safety of accepting it again. Because of this, obvious weaknesses are accepted again and again, sometimes without a sufficiently serious attempt to remedy them, or to delay a flight because of their continued presence.
There are several sources of information. There are published criteria for certification, including a history of modifications in the form of waivers and deviations. In addition, the records of the Flight Readiness Reviews for each flight document the arguments used to accept the risks of the flight. Information was obtained from the direct testimony and the reports of the range safety officer, Louis J. Ullian, with respect to the history of success of solid fuel rockets. There was a further study by him (as chairman of the launch abort safety panel (LASP)) in an attempt to determine the risks involved in possible accidents leading to radioactive contamination from attempting to fly a plutonium power supply (RTG) for future planetary missions. The NASA study of the same question is also available. For the History of the Space Shuttle Main Engines, interviews with management and engineers at Marshall, and informal interviews with engineers at Rocketdyne, were made. An independent (Cal Tech) mechanical engineer who consulted for NASA about engines was also interviewed informally. A visit to Johnson was made to gather information on the reliability of the avionics (computers, sensors, and effectors). Finally there is a report ”A Review of Certification Practices, Potentially Applicable to Man-rated Reusable Rocket Engines,” prepared at the Jet Propulsion Laboratory by N. Moore, et al., in February, 1986, for NASA Headquarters, Office of Space Flight. It deals with the methods used by the FAA and the military to certify their gas turbine and rocket engines. These authors were also interviewed informally. Fortsätt läsa Feynman: Personal observations on the reliability of the Shuttle→
Since I got my HTC Magic phone, the second generation Android operating system from Google and a lovely phone I have worked out using two different softwares that I would like to share.
These softwares are CardioTrainer and BuddyRunner, two wonderful applications to help you run well when doing exercise. Both offer similar features and are mainly aimed at runners that want to keep statistics on their exercise and perhaps also their competitions.
But what do they do? To make a long story short they are both personal trainers and logging instruments that can upload your running data to a web site where you can review what you have done and compare runs over time.
They are using the GPS in the phone to log your position periodically and thus can calculate your speed. They also measure the time and therefore knows at all times your speed and pace, the distance you have ran so far and in what time you did it. If you are using earphones and listening to music on your Android mobile as you run they will muffle the music or silence it completely and announce the running data periodically.
Feature-wise they are very similar, CT offers more settings to smooth out GPS positions during a run which can be good if you get bad measurements occasionally but won’t really help much in the long run, so to speak, but after testing the two producs side-by-side I can only conclude they are very similar in the distance they measure when running. The distance on both of them is perhaps a bit on the conservative side compared to distance measured on map or with a really good outdoor GPS (Magellan eXplorist XL) which shows a slightly longer track most of the time. Not certain why this is but they seem to be on the conservative side. My 2 km track registers as 1 850 meters roughly and that is 7.5% on the conservative side.
CT has a huge disadvantage for us Europeans, the tracks it records are shown in metric units on the handheld if you set it up to do so, but on the website everything is by imperial measurements which is really sad because it is otherwise a very good application. I have written them and they are looking into developing it. In fact there’s been two new versions of CardioTrainer released recently both with some small improvements.
BuddyRunner however has a really wonderful web site where you can see the run on a Google Maps interface, statistics on your run such as pace for each part of the run, and elevation. It is interesting to see the elevation go up and the pace time per km increase at the same time. You can compare several runs (up to three) download your running track and it keeps tracks of your records, longest, fastest and so on. Over all it is a much more developed web site than CardioTrainer has. However the application on the handheld is less sophisticated, it does not have the same filters and settings as CardioTrainer does and when it speaks to you it always abruptly pauses the music, the CardioTrainer can lower the volume but keep the music running which is better if you are trying to keep your pace to the music.
In the phone however both applications are very similar however and the settings screen also offers settings to change the announcer frequency and the contents of the announcing messages. BuddyRunner performs well int he background but CardioTrainer wants to run in the foreground, otherwise it pauses. CardioTrainer can also automatically play a certain playlist of music for you while BuddyRunner just leaves the music player alone.
Sharing your things with others is easy on the BuddyRunner, the application and webside can write RSS feeds to your Facebook, Twitter or Friendfeed site and so on, you may show your dashboard to anyone you like, they can’t manipulate it unless you log in but they can leave a comment on your run if they want to.
CardioTrainer has a secret passcode to the webside, you can not display it without this code and when you enter the code you may also remove runs and modify the content, so you would not want to post that publicly. There is also right now no integration with Facebook, Twitter and similar sites, no RSS feeds and the tracks can not be downloaded from the site.
In the end the factor that is the most deciding one for me is the website. BuddyRunner has a much better web site and I love the feature that you can download your runs in GPX format to have them displayed on Google Earth or some similar mapping software if you like. Great stuff!