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Comment This is so bizarre I'm not sure what to make of it (Score 3, Insightful) 228

The article footer implies that he's some kind of cooking science wizard, but I have trouble believing that Nathan Myhrvold has ever done more with an oven than toss a slab of meat in it. I'm no expert, but I've baked an awful lot of cakes, cookies, breads, and pastries, and I find this article very confusing:

Most of us bake, roast, and broil our food using a technology that was invented 5,000 years ago for drying mud bricks: the oven. The original oven was clay, heated by a wood fire. Today, the typical oven is a box covered in shiny steel or sparkling enamel, powered by gas or electricity. But inside the oven, little has changed.

Weird condescension towards "brick dryers" is a running theme of this article. To see how ridiculous this is, I invite you to consider a nineteenth century cake recipe with its many methods for determining correct oven temperature and shielding parts of the cake from the oven walls so that it bakes evenly. Turning a knob to set an arbitrary temperature, while imperfect, is a *vast* technological improvement over wood-fired ovens. (Remember: just because it's analog (or non-electronic!) doesn't mean it's not technology.) Likewise, the metal that the oven is made from represents thousands of years of technological advances in itself.

Preheating always seems to take an unreasonably long time because ovens waste most of the hot air they generate. The actual amount of energy required to reach baking temperature is quite small: Just 42 kilojoules will heat 0.14 cubic meters of air to 250 C. The heating element in a typical domestic electric oven supplies this much energy in a mere 21 seconds. Unfortunately, the heat, which originates in the heating coils of an electric oven or the burner of a gas oven, must pass through the air to get to the walls, and air is an awful conductor of heat, only slightly better than Styrofoam. Even worse, air expands when heated, so much of it flows out of the vent, heating the kitchen rather than the oven.

But the oven walls will heat the air anyway, so how much energy would we really save by heating the walls directly? Pre-heating is only a fraction of the oven's total operating time. And wouldn't an electric burner also produce radiant heat? And then a few paragraphs later:

As soon as you open the oven door to adjust or check on the food, nearly all the hot air spills out. The puny electric element or gas burner is no match for such large surges of cool air, so the temperature in the oven plummets, and it recovers slowly.

which is totally inconsistent with what he said earlier.

At 200 C or below, convection moves most of the heat. But at 400 C, radiant energy starts doing a fair amount of the heat transfer. At 800 C, radiation overwhelms convection. Why couldn’t we have an oven designed to cook primarily by convection at low temperatures that switches to radiant heating for high-temperature baking?

As others have mentioned, this is a Fahrenheit/Celsius error at best and a non-sequitor at worst. The highest normal baking temperature is around 500 F (260 C) unless you're going crazy with pizza. If the article's numbers are correct, we should totally ignore radiant heating! (I don't think they are.) And I'm not clear on how the oven is supposed to "switch" to radiant heating. If the walls are hot enough to radiate, you get hot air for free. If the air is hot, it heats the sides of the oven.

Myrhvold next dives into a laundry list of suggested improvements, which fall into a few categories:

1. Stuff that already exists, but is expensive.
2. Stuff that's not done because it's too expensive and/or inconvenient.
3. Complicated gimmicks that require recipe-specific behavior.
4. Star Trek.

And you’re not going to be able to stop a cook from opening the oven door on occasion ... But designers could prevent that blast of cold air by building a blower into the door frame that generates a “curtain” of air whenever the door is opened, retaining more of the preheated air in the oven. ... Designing one for an oven is trickier because the chamber is small and turbulent currents could do more harm than good. Still, it could be done.

Personally, I haven't found the occasional door-opening to be a big deal. It is discouraged for delicate foods like cakes. But clearly we need a complicated, expensive air curtain that either runs constantly or turns on in an instant. Nobody knows how to do it and it might be more trouble than it's worth, but Myhrvold is *sure* that someone (not him) will make it work.

I'm going to skip most of the broiler stuff since I don't broil, but a couple things stood out:

Electric broilers use bars or rods made from Nichrome, an alloy of nickel and chromium (and often iron) that heats up when electricity passes through it. With reasonable energy efficiency, electric broilers can heat quickly and reliably to temperatures as high as 2,200 C. Maximum settings are typically restricted to 1,200 C in order to extend the life of the heating element and avoid charring the food.

Nichrome melts at around 1400 C (2550 F). I strongly suspect this is another unit error.

You can make a broiler cook more evenly with a simple DIY project: Install some shiny vertical reflectors near the edges of the compartment. Another good way to ensure that food browns evenly under a broiler is to wrap the dish with a reflective foil collar. But why should you have to jury-rig a fix? It wouldn’t be hard for oven manufacturers to build reflective materials into the oven. Viking Range is developing stainless steel cavities that are more reflective, but they need better materials that are easy to clean and don’t discolor when heated to high temperatures.

Not sure if I should be more bothered by the idea of removing tarnish from my oven in order to cook, or "all it needs to work is a major advance in materials science".

But technology offers a fix here, too. Oven designers could put optical sensors in the oven chamber... And a camera in the oven could feed to a color display on the front panel ... a decent optics system ...

Let's talk about what "in the oven" means for electronics -- 250 C. Consumer-grade electronics stop working about 85 C (at best). Higher-grade stuff can go up to 125 C. Beyond that you're talking about serious high-reliability components. Maybe he wants some kind of fiber-optic feed? But that doesn't sound like "a decent optics system". And again, there's more cleaning, which nobody likes.

Even when perfectly calibrated, however, the standard oven thermometer has a big problem. Water evaporating from the surface of the food carries away heat, leaving the food cooler than the surrounding air. Scientists call this temperature at the surface of the food the wet-bulb temperature (that is, the dry-bulb temperature minus any cooling by evaporation). The lower the relative humidity, the more evaporative cooling, so the greater the difference between the two temperatures.

Because most of the humidity in an oven comes from the food, adding food to the oven raises the humidity and, therefore, the wet-bulb temperature at the food’s surface. This means that bigger batches bake faster. Did you burn the holiday cookies last year? Blame your oven’s ignorance of its own humidity.

Cookie dough is usually very dry. The water comes from the butter and the eggs. I know he's looking for something everyone makes as a rhetorical device, but it's still a sloppy and misleading example.

And while you’re at it, perhaps you could solve a related problem: the inadequate precision of the humidity- and temperature-control systems. Both temperature and humidity levels stray from the set points more than they should.

That's an obvious cost saving. It's a solution to a different problem.

Finally, Myhrvold reaches the place where he should have begun:

Some other interesting technologies that make ovens more useful are already on the market. Newer models of steam ovens by Wolf Appliance

This is where the article loses me. Convection ovens with steam injection are far beyond "brick dryers". They're also only a few thousand dollars, which is expensive but within the reach of a hobbyist. *This* is the state of the art in home ovens. Why did we start with low-end household models? People use those because they're cheap or because that's what their landlord provided, not because they're good. Nobody's going to get any of Myhrvold's fantasy features without massive cost reduction. So is this a speculative article about the furthest reaches of oven technology, or is it about practical ways of improving oven design? Despite tap-dancing past major technical obstacles, the article doesn't claim to speculate. From near the beginning:

Yet oven manufacturers could solve every problem with existing technology, if only they would apply it.

But on the practical side, here's the only mention of increased cost in the article:

An oven could be manufactured today that could incorporate many of the technologies now available and go a long way toward turning today’s mere brick dryer into a true food cooker. It would have wet- and dry-bulb temperature controls, better thermostats, probes to go inside food, and sensors that detect hot and cold spots. All these features would add just a few hundred dollars to the cost of the parts.

I don't know where he got that number from, given that each one of those features is only found in a commercial oven that costs thousands of dollars more than residential models. Regardless, even his lowball estimate is doubling the price of a cheap residential oven. And some of these new features are complicated for the user and break backwards compatibility with existing recipes.

Maybe I'm being too hard on the guy. I should probably have more patience with this sort of breathless "more electronics solves every problem!" attitude, especially since it helps keep me employed. But more electronics won't do anything about my landlord, and that, not theoretical oven design, is the biggest problem with most people's kitchen appliances.

(I still can't get over the "brick dryers" thing. Brick making is a big deal! Has Nathan Myhrvold done anything in his life as useful as making bricks?)

Comment Re:what's the point anymore (Score 1) 113

I don't know much (ok, anything at all) about the Libre lines but the Dorado machines have some very unusual characteristics such as 9-bit bytes

Nice to know there's still some non-DSP hardware out there with oddly-sized bytes. Maybe not so nice if you have to develop for it, but it gives me examples to point to when people ask why C's data types are defined the way they are.

Comment Re:republican voters? (Score 1) 422

I, for example, would be OK with allowing just about ANYONE here as long as they are documented, aren't seriously ill, and either have a job waiting or valuable job skills.

So just about anyone, as long as they're the right socioeconomic class? That may not have been what you meant, but your totally subjective criteria all but guarantee that that's what you'll get. And that's exactly what I was talking about. What is it that's supposed to automatically make a poor person from Mexico a worse citizen than a middle class person from Australia?

Children of legal citizens or people with green cards, of course, are also OK.

Again, this may not have been what you meant, but tying citizenship to parentage is effectively reinventing the grandfather clause, which the fourteenth amendment was designed to prevent. And yes, there are people seriously trying to overturn the fourteenth amendment to help them deport the children of immigrants.

Comment Re:republican voters? (Score 2, Insightful) 422

There is NO HOSTILITY TOWARDS IMMIGRATION. There is however hostility towards lawbreakers and those who ignore our constitution and borders.

Why is this simple fact apprently impossible for you people to understand?

Because there have been large waves of immigration many times in our country's history, and each time produces the same backlash with the same rhetoric. It doesn't matter whether the immigration is legal, what matters is that different kinds of people are moving into "your" neighborhood and changing it. You can see this right now in Europe with the backlash against legal immigrants from the Middle East. People don't get that emotional over abstract legal principles without an excuse.

It's always the same -- they're too poor, they're criminals, they're not learning English, they don't share our values, they don't understand democracy (i.e. they vote for the "wrong" party), they're out-breeding us, they'll destroy America unless we turn them back. Two generations later the immigrants' grandchildren have assimilated and are indistinguishable from the general population. Then the next wave comes along and the whole cycle repeats again. So far it's happened to the Irish, Italians, Germans, Eastern Europeans of all sorts, Chinese, and probably others -- pretty well everyone except the original British colonists, and you know how *they* got all that land...

Comment Re:The poster is showing his prejudice. (Score 1) 240

I deal with them by having my household accessible on the Internet.

Sorry, I suppose I wasn't clear. Internet-controllable major appliances are a very new thing. Business travel is not. How were you dealing with these problems five or ten years ago?

Maybe you're having lots of problems from my appliances, but the rest of the 'net seems to cope just fine. I suggest you look over your own setup before you start blaming me for your havoc!

I specifically said in my reply to you that this isn't a problem with you personally, but rather with large numbers of appliances being sold to large numbers of people, many/most of whom will not maintain and protect the networked parts properly.

Comment Re:The poster is showing his prejudice. (Score 1) 240

Why should I spend the effort trying to guesstimate when I will come home from a service trip to Asia which will take me between one and three weeks, to have the thermostat scheduled at the most likely time? And what do I do if I guess wrong, and have to stay another two weeks?

Then you either have a minor increase in your electricity bill or you're a bit warm for an hour or so while your house cools down.

Why should I carry that inconvenience just because you feel my thermostat does not belong on the Internet?

Because many of these new unpatched network devices will be wreaking havoc on the rest of the internet. (Perhaps not yours personally, but you're not the only person in the world.)

How are you dealing with all of these problems now? Clearly you're able to function today. Although this:

I have no friend or neighbour who I trust to come by.

is a pretty big problem and seems like way more of a danger than bad weather or network attacks.

Comment Re:The poster is showing his prejudice. (Score 1) 240

This stuff already exists and it is already connected to the internet. It is an existing problem that will only get worse as more stuff is added.

Just because the equipment is present doesn't mean it's connected. At the very least, the user has to pick a wireless network and enter the password. I see your point, though.

Comment Re:The poster is showing his prejudice. (Score 1) 240

A truly special reply suggesting mitigating a theoretical, limited, network security vulnerability by quite literally leaving the physical keys to the castle out in public. Please hand in your risk assessment credentials at the door.

I think you misunderstand. I'm not saying you should leave a key right outside the door all the time. I'm suggesting hiding a key somewhere non-obvious, *temporarily*, as a backup method in case you can't have an actual human being present. The alternative is an always-on, globally-accessible network attack surface for your front door lock. If that's compromised, getting in is as easy as "send me X bitcoins and I'll open the door at Y o'clock".

Comment Re:The poster is showing his prejudice. (Score 3, Interesting) 240

A lot of those examples are solved problems, and at worst are minor inconveniences. Many IoT proposals can easily be replaced with three existing categories of solution: "other people", "paying attention", and "non-networked computing". To address your specific examples:

Thermostat: Schedule the turn-on in advance. Alternate, come home, move your luggage inside, turn on the AC, and go out to dinner.
Laundry machines: Check a clock every so often.
Broken fridge: Show failure status on an LCD. Or have a USB port that you can plug a laptop or a smart phone into.
Freezing weather: Ask a neighbor or a friend to check on your house once every day or two. You may already be doing this if you have pets.
Door opening: See above re: neighbor or friend, or hide a key somewhere.
Out-of-reach window shades: Close them before you leave for work.
Dishwasher: Assuming that scheduling is really that much of a money-save, start it manually before you go to bed. Or use a time delay. Or load the data into the washer via USB.

The more serious problems are much more rare, and that must be weighed against the constant vulnerability from having internet-connected appliances and the upkeep required to secure them.

Perhaps a better option would be to get away from the idea that networking should imply both internet access and full remote control. Is there any reason an embedded device can't limit communications to its own subnet? Stick an upgradable, patchable PC on the network to act as a master, and have it talk to the outside world. Meanwhile, the appliance should be designed at the hardware level so that remote access only gets you status information and the ability to trigger a few well-defined fail-safe modes. Using a stove as an example, you would be able to tell if the burners are on, or force them off, but you wouldn't be able to turn them on or change the heat setting.

Comment Re:No Way! (Score 1) 261

Thank you for the correction. There's still something I don't understand, though:

Fast forward out of the CRT era, and you have TV screens that do a lot of the same things computer monitors started doing years before. The precise horizontal timing controls, buffering, pixel perfect rasterization without jitter... But the source still can't be synched with the screen because it's an external source.

My understanding was that modern HDTVs are computer monitors are essentially interchangeable (the panels are the same, at least), and that HDMI video and DVI-D are very similar. Digital video is of course encoded for a fixed resolution. So what's the difference between, say, a PC decoding Blu-ray video into a monitor vs. a set-top player decoding the same video into an HDTV?

Comment Re:No Way! (Score 1) 261

The whole reason why they went with 4k instead of 2160p for the name is because 4k is shorter, easier to say and looks like it is bigger than 2160p.

It's also a more accurate name in that horizontal resolution doesn't vary with a movie's aspect ratio. A "1080p" movie could be 1920x1080 (16:9) or ~1920x800 (21:9) or any other vertical resolution. The 1920 ("2k") is the real constant. I think the usage of lines was a holdover from the days of analog TV when vertical resolution was discrete but horizontal was continuous.

Comment Re:Ground down (Score 1) 1198

Sorry for this long cri de coeur, but you guys are my peeps and the responses broke my heart. You're my guys, my people, my tribe. Can't you back us up?

Thank you for posting. I'm sorry that so many of my brethren willfully ignore the direct personal experience of many, many, many women in favor of a comforting fantasy. Hopefully at least a few of them will be persuaded by your words.

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