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Who controls the HVAC at work?

CityZen Annoying engineering with limited local control (216 comments)

So there are thermostats on the wall, but they have only limited control:
- the building central HVAC produces only 1 temperature of air: either hot, cold, or unmodified.
- the temperature of air produced centrally depends upon the outside temp and the time of day.
    (ie, the thermostats have no control over that!)
- on cool days, hot air is produced; on warm days, cold air is produced, except:
    outside of work hours, it seems the air is mostly unmodified (not heated or cooled much).
- the thermostats control the venting such that you either get the central air or recirculated local air.
- (I haven't figured out what controls whether the blower runs or not.)

The net result does seem to be that you are overheated in winter, overcooled in summer,
except after work hours, when it becomes a reasonable temperature.

about 2 months ago

Major ISPs Threaten To Throttle Innovation and Slow Network Upgrades

CityZen Re:Please support the FCC to do the right thing (286 comments)

While I won't argue that you are wrong, I'm sure the cable companies would be pleased if people just thought "eh, what's the point in trying to change anything?" and didn't do anything.

That's how we got to this situation in the first place.

An alternative way out of this BS is to develop technology to bypass ISPs. Start setting up mesh wifi, or something. Figure it out.

about 2 months ago

Major ISPs Threaten To Throttle Innovation and Slow Network Upgrades

CityZen Please support the FCC to do the right thing (286 comments)

We all know this is BS. But we also know the FCC doesn't have much backbone. U.S. folks, please show them your support:

You may also write your senator or member of congress:

Comments or complaints sent to any of the above may do a lot more good than any posted here.

about 2 months ago

Microsoft Finally Selling Xbox One Without Kinect

CityZen Thank $DEITY for competition! (227 comments)

Competition can suck, but it's usually worse (for consumers) without it.

In this case, the worst effect of competition is that you might have to buy two game consoles to play every game that you would like to.
It beats paying 2x for the only game console with no competition.

about 2 months ago

Distracted Driving: All Lip Service With No Legit Solution

CityZen Re:There is this button. (184 comments)

And your teenage driver will certainly follow this advice, just like he/she followed every other piece of useful advice you have offered.

about 3 months ago

Distracted Driving: All Lip Service With No Legit Solution

CityZen Re:Just replace the driver (184 comments)

Hear hear! I'm anxious to see the day when people-driven cars are in the minority.

about 3 months ago

For $20, Build a VR Headset For Your Smartphone

CityZen Field of View (50 comments)

Half-baked solutions like this will have limited field of view (among other shortcomings). In order to get a wide FOV (which is important for immersion), Oculus is using very powerful aspheric lenses, which necessarily result in a distorted image. The distortion is "undone" by doing a pre-anti-distortion of the desired images prior to displaying them on the screen.

Latency will be another big issue, especially from tracking using a webcam that's probably running at 30hz.

I think that this stuff is great for experimenters who want to get a taste of VR on the cheap. However, it is a far cry from well-engineered setups.

about 3 months ago

Switching From Sitting To Standing At Your Desk

CityZen It's not binary (312 comments)

Obviously it's a problem to sit all day. But it's not a binary decision between sitting all day and standing all day.

Like everything in life, the key is "balance": not too much, not too little.

Keep using a chair if that's what you like. Just be sure to stand up, stretch, stroll around a bit periodically.
Set a timer if you need to remind yourself.

If you like to stand, that's fine too. You also need to move around periodically, or even sit down.

about 3 months ago

Algorithm Challenge: Burning Man Vehicle Exodus

CityZen Re:The playa exit is not the problem. (273 comments)

Then the answer seems obvious: Schedule the last day's events in order from most to least interesting, making sure to have a decent progression towards inanity as you get towards the end. People will naturally trickle away, as they decide the next events are not worth attending. (Perhaps the whole week should be scheduled with the most interesting events in the middle, and the more inane towards start and finish.)

Another possible answer comes up as well: treat the exit line like a Disney theme park entrance line: make it interesting enough to be in, but never interesting enough to hold anyone up.

about 4 months ago

Ask Slashdot: Experiences With Free To Air Satellite TV?

CityZen Re:I use Linux (219 comments)

> Never the less Linux has excellent support for various DVB/ATSC hardware.

One reason for this is that many receivers (set top boxes) use Linux as their internal OS.

about 4 months ago

Ask Slashdot: Experiences With Free To Air Satellite TV?

CityZen Re:Are you in the USA? (219 comments)

Lyngsat is the best place I have seen to get information about what programming is available. However, its organization takes some getting used to.

The page linked above shows the programming that originates from the US but is broadcast around the world. Similar pages can be used to find programming originating from other countries. However, you need to understand what satellites are viewable from your location.

Other pages are those that show what's available from satellites you can see, such as:
This page shows the satellites that broadcast to the US, ranging from 61.5 W way over toward the east to 139 W way over toward the west. If you are located on the east coast, you may have trouble receiving 139 W unless you have a clear line of site toward the west and a perhaps larger-than-typical dish. Similarly, if you are located on the west coast, you may have trouble receiving 61.5 W. Satellites that are more directly overhead your particular longitude will typically be easier to receive. You can find your own longitude very easily by googling your zip code plus "longitude".

Once you're looking at a particular satellite, say Galaxy 19:
then you need to understand the information that's presented. The first table lists frequencies in the ~4000 range, which corresponds to C-band. To receive these, you need a "BUD" (big ugly dish) of size 6-12 feet (2-4m). The next table lists frequencies in the ~12000 range, which corresponds to Ku-band. These can be received with a 30" (0.75m) dish.

The next columns to pay attention to are the provider name and the system encryption. Look for the "F" icon in the encryption column, indicating that the channel is FTA. Also confirm that the first entry for the transponder in question shows "DVB-S" (or "DVB-S2") and that this is compatible with the receiver you have. The first entry provides info about the multiplexed stream, whereas the subsequent entries provide info about each individual channel within the stream. A decent receiver will be able to figure out all these details itself, but older hardware requires programming in some details.

There's really a couple of ways to use FTA. One is to just set up a system locked to a given satellite and stick with a channel or small set of channels that are stable. The other way is to hop around different satellites and see what's available, since programming does change over time. For this, it's important that your receiver has "blind search" capability (which should be pretty common by now, but you should verify). Having the ability to program the channels easily with a computer program is another nice feature that many receivers offer. This can be a lot better than fiddling with the remote and endless menu layers. And, of course, a motorized dish mount makes it easier to change satellites.

A final word before you embark on this: Lots of these channels have online viewing options, which can be much less frustrating to view (or they can offer a different type of frustration). At least you won't have to fiddle outside with dish alignment on a rainy day to peak the signal. You can instead learn about proxies from the comfort of your desktop.

about 4 months ago

Ask Slashdot: Re-Learning How To Interview As a Developer?

CityZen A couple of tips, based on a recent interview. (218 comments)

When I interview someone, I ask them to explain something to me. A good candidate can provide a concise overview of the topic and then work through it in a coherent manner, seeking and taking in feedback from me to see if they're explaining things at the right level. Just wandering around the topic isn't so good. It's okay to say what you know and what you don't know.

Another thing I do is to ask them to solve a problem (either a simple but slightly tricky coding problem or a problem about a technology we've discussed). What I like to see is someone who can explain their thought process as they go. If they get stuck, they should be asking questions. But just sitting there thinking quietly isn't a good sign, especially when they don't come out with a good answer eventually.

You do need to find a good balance between talking too much and being too quiet. To do this, it is important to seek feedback and take queues from the interviewer. This kind of interaction is key to "working well with others".

about 4 months ago

How Do You Backup 20TB of Data?

CityZen Re:Hmmm... (983 comments)

The 6.25TB is "compressed" capacity, while the "native" capacity is 2.5TB.
That tape cartridge will cost you about $70, plus you need a drive for it (about $2000).
A 3TB hard drive goes for about $100.

To handle 20TB:
7 x 3TB HD's = $700.
8 x 2.5TB tapes + 1 tape drive = $2560.

You'd need quite a few copies of the data before the tape drives make more sense economically.

about 4 months ago

I'd prefer military fiction books that are ...

CityZen Doesn't matter (236 comments)

It's the writing and characterization that matter.

I loved Patrick O'Brian's Aubrey-Maturin series, set in the 1800's. There was a bit of tedium initially in his detailed descriptions of sailing procedures, but his lively characters made it worthwhile, and eventually even the sailing bits became interesting once you became more familiar with the topic.

about 5 months ago

A Strategy For Attaining Cuban Internet Connectivity

CityZen What's their cell phone strategy? (119 comments)

Wouldn't it face the same issues?

As far as internet, the people may wish to look at mesh wifi setups.

about 5 months ago

Dead Reckoning For Your Car Eliminates GPS Dead Zones

CityZen Re:I work for an automotive telematic unit supplie (151 comments)

Why 3D? Because some places have lots of elevated highways (as well as parallel roads underneath them).

But mostly because GPS works in 3D, and re-acquiring the signal is faster the more accurate the 3D estimated location is.

about 6 months ago

Yota Phone Launches With Secondary E-Ink Display

CityZen Pixel Qi? (72 comments)

Yes, why don't many more devices use the Pixel Qi display? You know, the one that's a normal color LCD when backlit, or a monochrome very-low-power LCD when front-lit (ie, by ambient lighting). Seems like it would be ideal for phones and smart watches.

about 8 months ago

The Science Behind the InfinitEye's Panoramic Virtual Reality Headset

CityZen Single FOV number no longer adequate (42 comments)

With these somewhat asymmetric FOVs, a single number doesn't provide enough information to understand what you're getting.
What's needed now is the "inside angle" and the "outside angle", where:
- inside angle = how much either eye can see toward the other eye
- outside angle = how much either eye can see away from the other eye
(in either case, measure the angle from "straight ahead" over to the cut-off point where you can no longer see anything)
In a symmetric system, both of these numbers are the same (or pretty close, anyway); you'd just add the two to get regular FOV.
You don't want the inside angle too small, or else you'll feel like you've got a huge nose (or your hand between your eyes).
Making the inside angle large is complicated by the fact that the displays will run into each other.
Making the outside angle large is easy by comparison.

about 8 months ago

CMU AI Learning Common Sense By Watching the Internet

CityZen Re:It's learning common sense? (152 comments)

You can learn lots of common sense from the internet:

- Whatever you see there, learn *not* to do!

Since mostly we post the epic failures of others, this technique will increase survival skills dramatically.

about 7 months ago


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