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cliff

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I think I was the person who originally proposed to implement the crew control UI in a web browser, and I participated in a week-long retreat in beautiful Bend, Oregon where we implemented the first prototype.

At the time, some very good flight software engineers had been working diligently on a new UI framework that was written in the same code style and process as the rest of our flight software. However, I noticed a classic problem - we were working on the UI platform at the same time that we were trying to design and prototype the actual UI.

I made some observations:

1) We can create a prototype right now in Chrome, with its incumbent versatility.

2) The chip running the UI can actually reasonably run Chrome.

3) Web browsers are historically known for crashing, but that's partly because they have to handle every page on the whole Internet. A static system with the same browser running a single website, heavily tested, may be reliable enough for our needs.

4) We can always go back and reimplement the UI on top of the space-grade UI platform, and actually it'll be a lot easier because we will know exactly functionality we need out of that platform.

The prototype was a great success; we were able to implement a lot of interesting UI in just a week.

I left SpaceX before Crew Dragon launched, so I'm not sure what ended up launching or what the state of affairs is today. I remember hearing some feedback from testing sessions that the astronauts were pleasantly surprised when we were able to live edit a button when they commented it was too hard to reliably press it with their gloved finger.

As for reliability, to do a fair analysis you need to understand the requirements of the mission. Only then can you start thinking about faults and how to mitigate them. This isn't like Apollo where the astronauts had to physically reconfigure the spacecraft for each phase of the mission -- to an exceptionally large extent, Dragon flies itself. As a minor example of systemic fault tolerance, each display is individually controlled by its own processor. If a display fails, whether due to Chrome or cosmic radiation, an astronaut can simply use a different display.

Also, as a side note regarding "touchscreens" -- I believe some (very important) buttons did launch with Crew Dragon, but buttons and wiring are heavy, and weight is the enemy. If you're going to have a screen anyways, making it a touchscreen adds relatively trivial weight.

Other games have 'start with partial download' technology. In fact, the core tech of the team that eventually created Valve's Steam was downloading assets on-the-fly so that you could start playing a game before everything was downloaded.

I worked on Guild Wars 2, which has this feature. I made a first prototype of it that streamed all content on-the-fly. It's pretty easy to implement - you have an abstraction that asynchronously loads a file off of the disk, and you can just make that download from the network instead.

The tricky part is when you want to ensure all the assets are there for a specific area before you load in, or simply knowing what order to download things in. For example, there was a starter area of Guild Wars 2 that spawned monsters from many other areas, this meant that the manifest of what was needed was enormous for that area.

So the 'playability' threshold becomes a trade-off between game experience (assets popping in as you play) and quick entry.

The website says you're planning to build your own manufacturing plant. What will that plant do? Will you actually be manufacturing your own medication?

If so, would that include manufacturing the active pharmaceutical ingredients or will you be sourcing them from generic manufacturers and then making the final drugs at your plant?

DOTT is a totally free-standing game -- and amazing.

They address this in the linked article (also from personal experience) -- you really don't need any context from Maniac Mansion to thoroughly enjoy DOTT and they are really totally different games in style and substance.

Your're probably right, but maybe it doesn't matter? Voice traffic is a diminishing percentage of overall cellular traffic. LTE optimizes for the increasing majority of traffic - data.

There are extra advantages to LTE -- for example, T-Mobile is using it to make it so that you can seamlessly handover phone calls between cell towers and wifi access points (using IMS, not VoLTE). Previously this was only possible via complex technology embedded in the phone's baseband (UMA).

More calls routed over wifi means less cell utilization.

I remember seeing this before.

I think it's really cool, though in the article I read before one major block to implementing this is that you'd be splitting up group boarding (of even 2 people travelling together).

I feel like that might be a tough message to try to explain to everyone at the airport, since in general people are worried about everyone in their party making it on the plane safely and with all their stuff. Gate agents have enough worried customers as it is.

Seattle, WA - ArenaNet

Looking for Web, Mobile, and Server (C++) programmers for an upcoming AAA MMO's extended experience -- bringing our game to web & mobile.

Web - http://tbe.taleo.net/NA5/ats/careers/requisition.jsp?org=NCS... Server - http://tbe.taleo.net/NA5/ats/careers/requisition.jsp?org=NCS... Mobile - http://tbe.taleo.net/NA5/ats/careers/requisition.jsp?org=NCS...

Neat fact about our web servers - we host V8 (like node.js) so web server logic is written in asynchronous javascript.

Contact cliff - arena.net

Just the Bill 17 years ago

You're still sending the password I entered back to me in an email in plaintext, even if you're not keeping it.

This is considered horrible practice.

I was excited about your product until I received an email with my password in it.. it just killed my enthusiasm. At some point I'll look back, but for a site that stores financial data...kinda scary.

Nexus One 17 years ago

The description might be sufficient, but it's inaccurate. You can't say AT&T 850/1900 and T-Mo 1700/2100 in one sentence. It's not the same context. You can say AT&T 850/1900 and T-Mo 1700.

The point is it's more difficult for phone manufacturers to make world phones for AT&T because they have to use up two bands just for AT&T, and those two bands are not commonly used in Europe or Asia.

Nexus One 17 years ago

It's actually a little more complicated than this and the terminology makes it very confusing. The key to this is that the frequency band is different from the actual frequencies used for the radio.

Much of the world's 3G usage is on the 2100 frequency band. This actually operates on two frequency ranges, ~1900 uplink and ~2100 downlink.

In this same vein, AT&T has 2 separate frequency bands, 850 and 1900. 850 operates on ~824/~869 and 1900 operates on ~1850/~1930.

T-Mo actually only has one 3G frequency band, 1700 MHz. This operates on ~1710/~2100, but actually this is not compatible with the world-wide 2100 frequency band.

Most, if not all, 3G T-Mo USA phones support at least the 1700 and 2100 frequency bands. Nexus One also supports 900 MHz, which makes sense since Vodafone uses that band in Europe and Nexus One will soon be on Vodafone.

See http://en.wikipedia.org/wiki/UMTS_frequency_bands for more exact details.

But you're helping break the internet.

When I write software, thanks to people like you now I can't depend on DNS to return accurate results. Another example of this is web browsers, which cache DNS beyond the TTL in order to provide a slightly faster experience. In the process, they break GSLB, which can no longer operate optimally since it can't rely on users re-querying DNS after the TTL of their answer expires.

Most folks are quite happy with your default experience, but that's because they're ignorant of the ramifications.

The US has a system. It's called ACH (Automated Clearing House).

You can find many banks in the US that offer free transfers between accounts using this system. Examples include ING Direct and USAA.

I use this all the time, and never write checks.

Actually, no.

UMA-equipped phones support what is called Unscheduled Automatic Power Save Delivery, an extension to wifi which reduces wifi battery consumption both when idling and when on a call to about the same level as a cell connection.

UAPSD (branded as WMM Power Save) is part of the WMM WiFi extensions, which are a part of most consumer wifi routers.

So, T-Mobile is pretty bad at explaining all this, and majorly screwed up branding and markering.

T-Mobile has two related but different services, which have been called T-Mobile @Home, and T-Mobile HotSpot @Home (now called wifi calling). @home is a home-phone replacement service, which comes UMA-equipped with a POTS phone plug for you to plug a phone into. HotSpot @Home is actually the service the parent is referring to, which can be considered 'femtocell using wifi'.

The way it works is -- your phone needs to connect to T-Mobile's GSM core network one way or another. Normally it connects over the mobile network, but UMA-equipped phones can connect via a VPN (IPsec) connection to T-Mobile. Once connected it speaks the same GSM language as it would speak over the air, so everything works, voicemail, phone calls, text messages, etc.

UMA is actually pretty awesome -- it can hand-off midcall back and forth between wifi and the cell network, unlike AT&T's femtocell solution.

Another HUGE hidden feature: As long as you can connect over wifi, your phone can connect to T-Mobile's network and send/receive calls, text messages, everything, using home area rates. Anywhere in the world. Billing over UMA works just like connecting to the cell network when you're at home.. so if you have unlimited at home you get unlimited UMA, or if you have 500 minutes you get the same 500 minutes.

This works on ANY wifi network, not just T-Mobile's routers. T-Mobile's Hotspot network of Wifi routers is specially configured to let UMA-equipped phones connect to T-Mobile's GSM core without having to pay.

In summary, T-Mobile's UMA service is awesome, but T-Mobile doesn't seem to be able to tell the world how awesome it is.

Sidenote: I used to work for HTC, and I kept trying to convince everyone of how important UMA is. It's a technologically superior solution to femtocells, but for some reason femtocells seem to be 'winning'. They are slightly easier to explain (a miniature cell phone tower!), but they actually really suck in comparison to UMA. It's tragic to see it happen.

They very much believed that their optimized interpreter would be faster and better than JITing. And it is optimized -- they took into account cache locality, ARM instruction size, etc. You can read the design doc. They spent a lot of time on it.

This is awesome.

The transition part especially reminded me of iMUSE (http://en.wikipedia.org/wiki/IMUSE) which creates seamless transitions between music tracks in LucasArts games as you move between areas.

This significantly enhances the immersion of the games, and 99% of the players probably never even noticed. And that's the point. They're not supposed to notice. They're supposed to be immersed.