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Some advice for beginners on pay-as-you go e-scooters

Posted by admin |

I was supposed to help some colleagues with their first experiences on pay-as-you go e-scooters this week, weather permitting. Well the weather was not cooperating, but I decided to write down some things I was going to tell them:

Use a helmet and possibly other protection at least in the beginning

The big problem with e-scooters even if you are used to bicycles, is the small wheel size. They can dig themselves into holes and stop at curbs, if the height difference is bigger than half the diameter of the front wheel. They also do not turn that smoothly beyond a certain angle. So a helmet can be good in the beginning!

Spread your feet out on the board

Put the balls of your feet as close to the front and back (diagonally) as possible, and angle them out to the sides (but still comfortable). For example front left and rear right. In that way you have the best balance and also the most weight shifting options.

Learn to jump off on the right side!

An e-scooter is actually in at least one way safer than a bicycle, and that is that you can dismount with ease and so place yourself further away from danger. It can also be used as a breaking method.

In countries with right hand traffic, the correct side to practice dismount on, is the right hand side of the scooter. The reason for this is that if you would dismount on the left hand side in a critical situation, you're basically jumping into the way of any oncoming bicycle or car. I've been close to doing that mistake, when a lady cyclist veered into my lane going head-on, while she was texting on her phone.

Keep your left index finger coiled around the handle at all times

Many scooters have a hand brake on the left hand side and you should favor those scooters, I believe, that do have one. If you ride with all fingers on the brake handle, your grip of the handlebar itself will be tenuous. Chances are that the times you really do need to brake will be in moments of instability and forces will try to pry your grip off the handlebar. By keeping the index finger on the handlebar you still have enough finger power on the brake lever while having good purchase on the steering bar itself.

When you start using the scooter, test the brakes. On some scooters the brake handle travels so far in towards the handlebar while braking that you'd pinch your index finger with the brake handle if you kept the finger around the handle, so obviously you can't have your index finger there in that case.

Scooters with the batteries in the steering bar will hit your shins

Scooters with the batteries in the steering bar are front heavy and lack mass in the rear so as you're leading the scooter beside you, there will be times when you turn or go up or down when the rear weel will lose contact with the ground and the board will come swinging at you and hit your shins. Ouch. You have my sympathies.

Aug 25, 2019 07:50

Nginx — Remember to cache content until the cache is actually updated

Posted by admin |

Caching when stale

If you cache something for say 6 seconds in Nginx, then only one request comes through per 6 seconds right? Not necessarily. It depends on how you have configured the behavior for when a cached entry goes stale.

If the backend takes a number of milliseconds to update the cache, other requests that are let through during that time (let through since the cache is stale) could overwhelm the backend application server.

In the default example in the nginx blog they do not cater for this "slip-through":

proxy_cache_use_stale error timeout http_500 http_502 http_503 http_504;

However it can be mitigated. For all versions of nginx there is an updating value you can add to the proxy_cache_use_stale directive. It will continue serving cached requests even when the cache is stale

proxy_cache_use_stale updating […]

Here is a comparison between not having the updating parameter switched on and having it on, for a slow backend application server with a low tolerance for load. In both cases 10 simultaneous user agents each doing 1 request per second for 30 seconds. Framework used is Artillery.js. Check the 95th and 99th percentiles

Request latency:
min: 33.7
max: 16763.4
median: 37.9
p95: 7666.3
p99: 15260.1
Scenario counts:
0: 300 (100%)
Codes:
200: 300

Now with the updating parameter added:

Request latency:
min: 34.3
max: 726.9
median: 38
p95: 43.4
p99: 70
Scenario counts:
0: 300 (100%)
Codes:
200: 300

Aug 22, 2019 03:55

Bruce Schneier on the nature of dishonest Internet influence operations

Posted by admin |

Bruce Schneier on the nature of dishonest Internet influence operations ("they're surprisingly inexpensive to run", "they will increasingly be seen as how the game of politics is played in the information age") and how to kill them, point by point.

 

https://www.schneier.com/blog/archives/2019/08/influence_opera.html

Aug 20, 2019 10:43

Humidex — one way of getting a truer measurement of the summer heat's effect on the body

Posted by admin |

Parts of Europe suffer a heatwave but you got to weigh in humidity to get closer to the real impact. Meteociel displays the Humidex readings all over Europe, taking humidity into account. Check chart below for guidance

Forecast for France and some surroundings https://www.meteociel.fr/modeles/gfs/humidex/3h.htm

Humidex measurements http://www.meteociel.fr/observations-meteo/humidex.php?region=eur2

Chart025
Click to view full-size image…

 

There may well be better scales for assessing this, but Humidex has the distinct advantage of actually being reported for European weather.

Jul 24, 2019 11:45

Voice over mic test by BoothJunkie:My take on which mics sounded best

Posted by admin |

I'm listening through a tinny laptop speaker, but here goes. The mic he is mainly testing, the VO 1-A is really good. It is better than the first mic he compares it too the CAD m179, and also edges out the Røde NT1 mic, although is has to be said that the Røde is good. I wonder if you ever can go wrong with a Røde mic. The Lewitt LCT 440 PURE in some ways better than the VO 1-A, I'd say maybe not as clear, but with a nice compression, that suits voiceover often I gather. The Neumann mics are better, but it makes you think by how much given the price. I am a bit interested in the Neumann KMS 105 BK  which is a cheaper version for stage use. 

Below is BoothJunkie's affiliate links for the different microphones. Haven't thought that much about the Sennheiser and the CAD e100s.

 

With headphones on

I have now listened with my Sony MDR-CD480 headphones,  and methinks VO 1-a still sounds better than the m179 and the NT1. The LC440 sounds a litlle bit better, less raw and less sibilant but otoh with more distortion. The e100s sounds better. The TLM103 sounds a lot (well maybe not a lot but in this context of listening intently) better.

Jul 22, 2019 12:20

The Neumann sound — it's true

Posted by admin |

Bandrew just tested a Neumann mic that costs $700. And I pretty much immediately recognised the sound of this mic as the sound of hosts and news announcers on Swedish high-end FM radio in the 1980s. I bet they had similar sounding Neumann mics. Now I want one. It's so much better sounding.

 

 

Here is a microphone in the "Ekot" news studio. Don't know what it is though:

11403123 1137518022928628 7128068138886291737 n
Click to view full-size image…

Jul 12, 2019 01:35

How to upload images with e.g. WhatsApp in Firefox

Posted by admin |

Images can show up blank. In that case:
In about:config, Set

privacy.resistFingerprinting.autoDeclineNoUserInputCanvasPrompts

to

false

and allow WhatsApp access to canvas data.

It seems to be enough to toggle this,  confirm access for Whatsapp, and toogle it off again We'll see.

Web WhatsApp shows blank/white image : firefox

Jul 10, 2019 01:30

A salsa video with Magna Gopal & June from Seoul 2008

Posted by admin |

For whatever reason, this dance video has stuck with me, I like it:

https://www.youtube.com/watch?v=GBWMOurhmpk

 

If the embed doesn't work, follow the link!

Jul 04, 2019 10:40

Taleb's fundamental notion: ­The world is nonlinear

Posted by admin |

A random like on Twitter reminded me of this old tweet:

 

taleb
Click to view full-size image…

 

Jul 01, 2019 12:01

Testing electrical scooters (kickbikes, mopeds) in Stockholm

Posted by admin |

Tried 3 electric scooters (kickbikes) rentals in Stockholm: Tier (Austrian, I think), Lime (American) and Voi (Swedish). The scooters are everywhere! I think the way they look & work though will evolve rapidly, because commercial use sets a different set of constraints.

  • Tier is the best scooter, but they become unavailable at late evenings
  • Lime has jerky accelerator
  • Voi is ok, with super availability and a stronger motor than Tier

Tier lacks external battery so I guess they have to collect all scooters every evening. Voi & Lime can just switch batteries. Hope Tier upgrades soon. It has smooth throttle & mechanical brake, & half the price/minute. These kind of vehicles the way they are designed today are front heavy & thus handle a bit weird.

tier
Click to view full-size image…

Update 2019-06-27: As can be seen above, some of the Tier scooters now have been fitted with external batteries (the black bulb halfway down the back of the steering column) afaict. The competition goes on… However I also see Tier scooters without this modification. Update 2019-06-30: Tier still shuts down the entire network at around 22.00 every day. That is truly weird. Also, their bikes seem to dropped back in clumps of four to six, near metro stations. Unless then, tier travellers like to travel and abandon their bikes in packs of six…

Better scooters ahead


Once they start designing their own rental vehicles they could well place the battery further back to ge a better weight distribution methinks. Update: I think that is exactly what Lime-S Generation 3 does! They do not mention it but you can see the space under the floorboard. And as you can see demonstrated in the above video I just found, Voi does it too. Also bigger wheels. I have not seen these new ones in Stockholm. Anyone who has been skating on inlines on surfaces with cones or stones, knows how much every extra couple of millimeters at the wheels help (in inlines from e.g. 72mm to 80mm). Voi will also try a three-wheeler as can be seen in the background of the above video.

An electrical moped

800px Blinkee electric scooter in Burjassot
Click to view full-size image…

Also tried the @blinkeecity (Polish company) moped. With a passenger I think it all weighed in at 218 kg! & you need to balance that with a wide stance due to the floorboard of what I'm fairly sure is a Viarelli Vincero. Good experience but this ain't no kick bike. Price/min not much higher than a kickbike though!

I think the moped itself weighs in at just below 90kg.

 

Jun 23, 2019 10:55