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MurMan

394 karma · joined July 23, 2015

Hi. Feel free to contact me via hotmail using "murray" dot "judy"

Murray

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MurMan··on Nukes, nubs and coners: The unique social hierarchy aboard a nuclear submarine
Former EO here. Every group on the boats gets an unofficial name. My favorite was the A-ganger's, the guys that took care of all the mechanical stuff that no one else wanted like the sanitary tanks: Turd Ranchers. Still makes me laugh ...
MurMan··on Did Jimmy Carter Stop a Nuclear Reactor from Destroying Ottawa?
I think it depends on what you call the reactor. I think of a reactor as the vessel that holds the fuel, moderator, controls, etc. From the NRX diagram, the reactor includes everything within the concrete "biological shield". Here's a link to the NRX reactor description:

https://inis.iaea.org/collection/NCLCollectionStore/_Public/...

The NRX was disassembled and rebuilt within a year. My guess is that Carter and others were lowered from the "revolving door" above the reactor in order to remove bolts as part of the disassembly process. The clothing worn was needed to protect the personnel from being contaminated.

MurMan··on Did Jimmy Carter Stop a Nuclear Reactor from Destroying Ottawa?
The story confuses the difference between radiation and contamination.
MurMan··on Elizabeth Holmes’s Last Pitch
> ... the dubious abilities of our nominally elite classes ... to competently mediate the difference between artifice and reality.

I wish there were more media introspection over how they fueled the hype. To me, the Theranos story of a 19-year old dropout revolutionizing blood testing technology was always suspect.

MurMan··on Intel CEO: Clients Want Custom x86-Based SoCs
> in the coming years Intel will cease to buy back shares, but will invest in new manufacturing capacities instead.

This is critical for Intel's turnaround. Good to have a CEO that wants to put money into process engineering and capacity than financial engineering to pump up the stock price to meet his personal compensation goals.

MurMan··on Abba Back After 40 Years with New Album, Virtual Concerts
Abba has always been the guilty pleasure that I'd never admit to my musician friends. Have to confess that I like their new song “I Still Have Faith In You”.
MurMan··on Lawrence Livermore claims a milestone in laser fusion
> There's also a firing rate issue ...

The NIF goal was ignition, not continuous power production. The original spec was one shot every four hours. Achieving one shot per day is close.

MurMan··on Elizabeth Holmes gives birth as Theranos fraud trial nears
Her current net worth is essentially zero now that Theranos has collapsed. Plus, she has a lot of legal bills to pay.

It wouldn't surprise me if her legal team points our how poor she is. Poor Elizabeth ...

MurMan··on Ignoring WHO call, major nations stick to vaccine booster plans
Both Pfizer and Moderna have stated that boosters will be needed this Fall. Pfizer says that immunity drops from 96% to 84% at the six month point. The good news is that the vaccine continues to protect against severe disease due to its effects on T-cells and memory B-cells.
MurMan··on The engineer preserving the last analog motion graphics machine (2017) [video]
Noticed that, too. He lives in Fletcher, NC about 20 minutes from Ashville, the home of Moog.
MurMan··on Nuclear Power at McMurdo Station, Antarctica
> I would very much like to know your take on why the Navy has this knack.

I think the obvious answer is that they have to. The Navy has a lot of technology that needs maintenance at sea. Problem diagnosis requires understanding. We didn't rely on black box replacement.

I had nearly two years of engineering math when I was drafted and joined the Navy. The Navy skipped all of the derivations and went straight to the concepts of limits, derivatives, and integrals. Even some differential equations that describe reactor dynamics. Calculations were limited to algebra. Testing focused on calculus concepts rather than numerical answers.

This produced technicians with the ability to understand how the power plant worked but without the formal math and physics need for power plant design.

The only thing I can offer about how the Navy selects people is that it presents the various training programs early, starting with the recruiters. Certain programs are presented as being most difficult and are described in glowing terms. The challenge was definitely an attraction for me.

MurMan··on Nuclear Power at McMurdo Station, Antarctica
> 90% of the people I started training with were gone in the first two years!

My experience too. Do you remember the "skyhook"? We'd return to the barracks after class and find that the guy next to you had vanished without a trace.

MurMan··on Nuclear Power at McMurdo Station, Antarctica
You're right about HN. Experts in all domains.

My experience is from the Vietnam era and doesn't apply today. I was drafted mid-way through an EE program when I got behind in units. Virtually all of us had similar backgrounds. The Navy had a knack for teaching nuclear physics & math to bright people with a high school education.

The S5W plant that I operated had virtually no automation. Just safety interlocks and a few automatic shutdowns. Everything was analog. The electrical controls used mag-amps: dumb and inefficient, but reliable as hell. Safety was achieved by detailed operating procedures and highly trained crews. We studied and drilled constantly. Most over-qualified group of people I've known.

There's no way that I could describe what it was like at sea in a few lines here. It might make for an interesting HN thread as there are other nuc's here. :-)

MurMan··on Nuclear Power at McMurdo Station, Antarctica
Just once, briefly when he did an inspection of our boat in Guam. My last memory of him was standing next to the ladder as he left. His pants raised as his ankle reached my eye level exposing a leg that was smaller than my wrist. To me, this was a perfect example of Rickover: a giant in many respects, but small and petty in others.
MurMan··on Nuclear Power at McMurdo Station, Antarctica
Oxygen generators use electricity (electrolysis), not steam.

Thankfully, we never had to use oxygen candles. Candles are effective only in a small closed space. That would have been a serious emergency.

MurMan··on Nuclear Power at McMurdo Station, Antarctica
Yes. Subs use low-pressure steam to desalinate sea water. Having lots of fresh water for showers was a huge benefit of nuc boats over diesel boats.
MurMan··on Nuclear Power at McMurdo Station, Antarctica
I was a nuclear power plant operator on a submarine during this period. Wanting another challenge (young & crazy ...), I applied for duty at McMurdo Station in 1971. My request was not approved and I was told that the Navy had a shortage of qualified submarine nuc's. Sounds like the Navy had already decided to decommission it.

I've always regretted not going to Antarctica, but this article makes me think that I dodged a bullet. This plant was a maintenance nightmare. Plus, operating a reactor with a mix of personnel sounds bad. We certainly had our personnel issues on subs, but at least all of us in Engineering had the shared experiences of nuclear power school, prototype training, and sub qualification.

MurMan··on When X-Rays were used at the Shoe Store
I remember these machines well. My father was a radiologist and wouldn't let us use them. He knew they were dangerous and the shoe sales people were unqualified.

As a side note, many of his fellow radiologists lost fingers because they didn't follow procedures using shields and lead gloves.

MurMan··on Nuclear power: Are we too anxious about the risks of radiation?
I assume that you're referring to USS Thresher and Scorpion. These weren't nuclear accidents.
MurMan··on Indian robot climbs trees to harvest coconuts
Is this contraption actually a robot? A robot has some automatic function or autonomy. I would classify this thing as a coconut harvesting machine.
MurMan··on Dating is better than ever with social distancing
I think dating is better. My experience is that it's now more about in-depth conversation than attending events. I think this is a great step forward. It has also eliminated the really risk-adverse people which suits me fine.

This assumes that you can meet people on-line. And if you struggle expressing yourself verbally, your experience might not be great.

Comedy, on the other hand, is suffering, as illustrated by these jokes. Live standup is prohibited in a lot of places. I've listened to interviews with comedians that say they can't get inspired when performing virtually. Then, there are all the controversial topics that used to encourage actual dialog but now trigger rage in the snowflakes.

MurMan··on The Sac State 8008: The First Full-Fledged Microcomputer (2008)
Doubt if an 8008 uC would have been a commercial success. It ran at 125 KHz with instructions taking around 20 clocks. Instruction set was very primitive compared to the 8080 and the address bus was only 14 bits wide. It was best suited for calculators and controllers.

I built an 8008 machine in 1974 with a whopping 256 bytes of memory and toggle switches for program entry in binary machine language. You could watch it execute subroutines in the address bus LEDs!

MurMan··on Paper maps, two-way radios: how firefighting tech is stuck in the past
In addition to all the reliability & usability concerns others have pointed out, don't forget the time when Verizon enforced data caps during the Mendocino fire:

https://www.npr.org/2018/08/22/640815074/verizon-throttled-f...

MurMan··on America Wants to Put a Nuclear Power Plant on the Moon
> Nuclear startup NuScale’s modular reactor uses low-enriched uranium, for example, but couldn’t meet the requirements for the moon without some modification and further development.

The NuScale reactor has a shipping weight of 700 tons and requires an on-site concrete pool of cooling water. Sounds like a lot of modification to me.

MurMan··on Cameras on San Diego streetlights turned off until ordinance in place
> You're lucky that in this case it helped you maintain your innocence, but that use will be in the tiny tiny minority.

What's your data source for this prediction? Are you saying that wrongful arrest and prosecution is a negligible problem?

> The actual solution to your particular problem is proper due process and rooting out police sloppiness and prosecutorial overreach, ...

Easy for you to say. Proper due process would have cost me a year or more of hell plus a lot of money. As for "police sloppiness and prosecutorial overreach", that's pounding on the table and has nothing to do with this discussion on cameras.

> ... not adding features to our society that make it easy for those in power to violate people's civil rights.

Cameras show when civil rights are violated.

MurMan··on Cameras on San Diego streetlights turned off until ordinance in place
I'm a San Diego resident that was falsely accused of a serious offense a few years ago. Surveillance footage from a restaurant saved me from prosecution.

I know that this is a minority opinion, but I'm in favor of cameras in public places. There will always be the potential for abuse even with strong restrictions, but I think the benefits are worth it.

MurMan··on Too Much CO2 Has an Unnerving Effect on the World's Trees, New Study Finds
Two of the three peer reviewers didn't agree with how the study extrapolated results to predict the effect on carbon. One reviewer wrote, "The conclusion about neutralizing the carbon sink ignores forest management ..."

Using a static analysis to predict complex system behavior seldom works.

I'm wondering about how a tree becomes unnerved.

MurMan··on Gravitricity – Fast, long-life energy storage
This idea assumes that the interior of the tower is empty space that could be used by the moving weight. Towers have an elevator for maintenance personnel that would reduce the available space. I'm guessing that the towers aren't high enough to store enough energy to justify the cost of the extra equipment.

I doubt that suspending the weight is the main structural issue. It's the high center of mass when the weight is at the top.

MurMan··on Small nuclear reactors: tiny NuScale reactor gets safety approval
> ... if indeed these reactors actually do tolerate flooding

The reactor modules are partially immersed in a pond, the ultimate heat sink. Cooling is passive, i.e., no cooling pumps, and does not require electrical power.

MurMan··on Testing a $1300 120,000lm water-cooled LED
Agreed. He's a likable chap.

But I'm not a fan of "builders" that get into high-energy projects, especially when they demonstrate disregard for safety. Using your fingers to check for high temp and doubling ordinary sunglasses around high-intensity light sets a bad example for even less-capable followers.

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