Category Archives: geek

Bicycle tyre Schwalbe Marathon Plus

The Schwalbe Marathon are remarkable tires. I think that I inadvertently rode for at least 100 kilometers (in consecutive riding sessions) with a grain of quartz embedded in the tyre.

Schwalbe Marathon Plus tire
Schwalbe Marathon Plus tire with a grain of quartz

According to a friend who regularly enrols in cycling expeditions in exotic countries, the tire is the primary choice for a world-trip because it’s so reliable.

Juvenile swift stranded in Luarca, Spain

A nestling swift (Apus apus) was lying in the ruins of a house at one meter over street level. It didn´t look injured. We did not touch it.

The pictures were taken in the first week of August in Luarca, a seaside village in the north of Spain.

Swift chick Luarca
Swift chick Luarca
Swift frontal closed eyes
Detail frontal closed eyes
Detail of head of swift chick
Detail of head of swift chick

We spent as little time as possible taking the photos. We did not see the parents coming in to feed the chick in the 5 minutes that we stood waiting at a safe distance.

The first fledgings show up around July 27th in Asturias, Spain, upon the phenology records. There is a great guide to take care of fallen chicks: Swift First Aid.

First arrival dates of swifts are a popular phenology record. Swifts in London arrive in April and May. I think that the duration of stay for Common Swift presence on the nest is a more interesting metric than the first arrival. Surprisingly, this metrics is still poorly studied in Europe (Tigges, U., 2007, The Phenology of the Common Swift Apus apus in Eurasia and the Problem of Defining the Duration of their Stay).

2 iphone units in 16 months and 10 reasons why Apple sucks

The facts:

I ordered an iphone 4S directly on Apple.com. 10 months later the unit stopped working; the phone would not start.
Booking an appointment at a Apple Store requires a bit of patience: the waiting time is of several days to one week. At my first visit my 10-month old unit was replaced by a new one.
6 months later the replacement unit stopped working
The replacement unit was diagnosed with a motherboard issue. The unit could not be recovered and it could not be repaired.

10 reasons why Apple sucks

The case raises a number of concerns about Apple’s customer service:

  • Apple’s guarantee for products ordered directly via Apple.com is limited to 1 year only instead of the 2 statutory ones granted in most of the countries in the EU
  • Apple Store refuses to provide the packaging box of the replacement unit. This refusal prevented me from knowing the IMEI of my replacement unit. This in turn makes all attempts to contact to their support a complicated and irritating process, either online or by phone
  • The guarantee of the replacement unit was limited to 3 months one, again materially shorter than the statutory scope in the EU
  • The is no way to recover any personal data on my iphone unit or via the backup at iTunes other than with yet a new Apple device.
  • Apple’s customer service is a non-geographical number. That means that the client pays for the call and Apple gets a kick back of the call from the local telephone operator.
  • Apple did not provide with a a escalation procedure to deal with their issues or an access to the customer Ombudsman at Apple. Apple’s support staff claimed that such procedures do not exist and that they could only provide me with the URL of a “feedback” form at http://www.apple.com/feedback/iphone.html
  • I also requested a way to dispose of my non-working unit. Their junk hardware is a hazardous waste with no recycling facility offered
  • Apple diverts their profits to Ireland to save taxes in most countries in the EU
  • The iphone is a sub-standard piece of hardware: it failed to sync over WiFi, the battery rarely lasts more than 12 hours under normal usage conditions, ie. no gaming
  • The iTunes software is a clunky and counter-intuitive piece of software: it failed to connect

Silence at Apple.com

I requested that you provide me with a replacement unit with a proper extension of its guarantee of 2 years from the order day of the original one.

All I got from my message was a thank you message at http://www.apple.com/feedback/iphone_thankyou.html

Thank you for your feedback on the iPhone.We cannot respond to you personally, but please know that your message has been received and will be reviewed by the iPhone Team. If we need to follow up with you on your ideas for improving the iPhone, we will contact you directly.
We appreciate your assistance in making the iPhone better.
iPhone Team
Apple

The iphone sucks and increasingly so

What’s a Watt

A Watt (W) is the unit of power of equal to one joule of energy per second.

In terms of electromagnetism, one watt is the rate at which work is done when one ampere (A) of current flows through an electrical potential difference of one volt (V), ie. W = V * A. If your computer monitor is plugged to the mains at 240 V and it requires 1.5 A, the power it spends is 240 V * 1.5 A = 360 W

A laborer over the course of an 8-hour day can sustain an average output of about 75 watts. In terms of sports biomechanics, mass times acceleration due to gravity times height divided by the time it takes to lift the object to the given height gives the rate of doing work or power. A human climbing stairs needs 200 watts of power.

The best non-doping cyclists in history could deliver almost three times as much power:

Miguel Indurain Bernard Hinault Eddy Merckx Jaques Anquetil
Tour de France Winning Years 1991-95 1978-79,81-82,85 1969-72,74 1957,61-64
RacingWeight (kg) 79 68 75 68
Height (cm) 187 173 183 174
Resting Heart Rate 28 bpm 38 bpm 44 bpm 45 bpm
Maximum Heart Rate 195 bpm 170 bpm 162 bpm 180 bpm
Lung Capacity 7.8 litres 7.2 litres 6.9 litres 6.9 litres
Power Output 550 Watts 450 Watts 500 Watts 400 Watts

A car engine produces 25,000 watts (approximately 33.5 horsepower) while cruising.

The net capacities of average nuclear power plants range between about 500 and 1300 MW (106 W).

Real-time monitoring of the demand of electricity in Spain
Source: REE Spain https://demanda.ree.es/demandaEng.html

The largest offshore wind farm in Germany, Innogy Nordsee 1, will have a combined capacity of 960 MW (106 W) to be delivered by 150-180 wind turbines. Spain had an installed capacity of wind power of 16 GW (109 W) in 2008 (source: REE). In 2012 wind power was, for the first time ever, the source that contributed most to the annual electricity demand coverage with a share of 21.1%. This compares with nuclear which contributed 21%.