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Philip Ngai
Works at Commercial Real Estate
Attended Massachusetts Institute of Technology
Lives in Fremont, CA 94539
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Philip Ngai

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I am in FLORIDA. Will be here for awhile. You coming soon?
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Chain reactions in modern american thermonuclear devices

It is commonly understood that a thermonuclear device is typically a two-stage device comprising a primary and a secondary. (1)

Most people think the primary stage is a fission device that ignites fusion in the secondary stage.

What is not as commonly understood is that each stage of a modern boosted weapon (also known as dial-a-yield) is itself a coupled fission-fusion-fission chain reaction for a total of fission-fusion-fission-fission-fusion-fission.
 
The primary stage is typically a hollow plutonium-239 pit (2), as its critical mass is much less than uranium-235. After conventional explosives implode the pit and cause it to go critical, a small amount of fusion fuel (usually 50/50% deuterium/tritium gas) at the center ignites and generates a large number of neutrons which increases the fission rate and thus induces a more complete fission reaction in the plutonium before the core explosively disassembles. Without boosting, a large portion of the fissile material will remain unreacted; the Fat Man bomb had an efficiency of only 17%, because it was unboosted. (3) The energy released by the fusion reaction in the primary is not significant, only about 1% of the total energy from the primary, it is the neutrons generated by fusion that are important.
 
Boosting is mainly responsible for the remarkable increase in the efficiency of fission weapons since 1945.

The secondary stage is typically a cylinder and comprises a heavy tamper surrounding the fusion fuel (lithium deuteride). At the center is a fissile plutonium sparkplug. It is this sparkplug that ignites first when triggered by the primary. The sparkplug in turns ignites the fusion fuel which is confined by the tamper. Fusion generates a copious number of neutrons and can cause the tamper to fission if it is made of an appropriate material such as uranium. 
 
Although un-enriched uranium can be used, the increased yield of enriched uranium makes it the preferred tamper material in light weight strategic weapons. One could argue that weight is very important in the highest priority application: submarine launched ICBMs. Weight and volume are precious and must be balanced against other essential performance parameters like maximum dive depth and missile range. Even land based ICBMs benefit from lower weight because it allows more re-entry vehicles to be carried. A bomber is more likely to be limited in the number of targets it can service but again, light weight could allow a smaller aircraft to perform the mission. Also, stealth aircraft are more survivable but then the weapons must be carried internally and volume is likely to be a limiting factor.
 
Fission  of the tamper (if it occurs) provides considerable energy yield, as much as half of the total yield in large devices. It also creates far more fallout than a pure fusion device (assuming airburst).
 
Footnotes:
1. It is believed that the W-53 9 Mt warhead carried by Titan II ICBMs was so large, 3 stages were required. The Mk-53 bomb was carried by B-52 bombers and in that role has been involved in several accidents.
 
2. Composite plutonium/uranium pits have been used when uranium was more plentiful than plutonium but a pure plutonium pit is smaller and is the current standard.
 
3. The Little Boy gun type device had an efficiency of 1.38% of the fissile material reacted.
 
A good resource on the subject:
http://www.sciencemadness.org/lan
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CH2M HILL has been awarded a contract for the expansion of the Los Esteros Critical Energy Facility, located in San Jose, California by its owner, Los Esteros Critical Energy Facility, LLC, an indirect, wholly-owned subsidiary of Calpine Corporation.

    The facility expansion will convert the existing natural gas-fired, simple-cycle electric generation peaking facility to combined-cycle operation. The plant currently uses 4 GE LM6000 combustion turbines. A steam turbine-generator, four heat recovery steam generators and auxiliary plant equipment will be added.

http://www.lowney.com/pdfs/projects/LosEsteros.pdf
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Sympathy for a SF liberal when caught up in an uncaring, all-powerful government bureaucracy, a person who (belatedly?) only wants the freedom to live her life as she chooses?

Somebody find me a tiny violin.
--

"The disempowerment of Eliana began on a very small level when her husband grabbed her by the arm during an argument," Melgar wrote. "It was exponentially magnified by the neighbor in whom she confided, who decided that Eliana's strongly held desire to handle her problems with her husband herself was inconsequential.

"The disempowerment of Eliana was then magnified again and again, by the police, the press, the district attorney, and finally even anti-domestic-violence advocates. How did it come to be that a system that was intended to empower women has evolved into a system that disempowers them so completely?"

Melgar writes that nobody consulted Lopez about what she wanted, which was to work on her marriage with her husband, whom she is not allowed to have any contact with. And now the family has no income because Mirkarimi has been suspended without pay.

"It's inarguable that women in dangerous situations need to be provided options to get out," the piece continues. "In Eliana's case, which was limited to her husband too forcefully grabbing her arm, the family was destroyed and it will take years before the victim and her child will be able to (maybe) put their lives back together."

Kathy Black, director of La Casa de las Madres, said California's law considers domestic violence a crime against society, not just against the victim.

"It's a crime whether the victim decides to proceed or not," she said. "I would never want to get into a situation where I was defining how much physical abuse would be considered domestic violence." Lopez is expected to return in a month, but when asked whether she will actually return, Melgar said she didn't know.

Read more: http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2012/03/28/BAS31NRKL3.DTL#ixzz1qWzkRmtg
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Russian Empress Alexandra Fedorovna on children

Our children naturally bring along with them a multitude of cares and concerns, and for this reason there are people who look upon the appearance of children as a misfortune. But it is only cold egotists who can look upon children in such a manner.
 
It is a momentous thing to take upon oneself the responsibility for these tender young lives, which can enrich the world with beauty, joy, and power, but which can also easily perish; it is a momentous thing to nurture them, form their character, – this is what one should think about when establishing a home. It should be a home in which children will grow up to a sincere and noble life, grow up for God.
 
No treasures in the world can replace for man the loss of truly incomparable treasures – his own children.
 
There are things which God gives often, and others that are given only once. The seasons of the year pass and return again, new flowers bloom, but youth never comes twice. Childhood and all its possibilities are given only once in a lifetime. Whatever you can do to adorn it, do it quickly.
 
Parents should be what they wish their children to be – not in words, but in deed. They should teach their children by the example of their own life. The greatest treasure that parents can leave their children is a happy childhood, with tender memories of father and mother. It will lighten the forthcoming days, it will preserve them from temptation, and it will help them face the harsh realities of life after they leave the parental roof.
 
May God help each mother understand the majesty and glory of her forth-coming endeavor, when she holds at her breast her infant, whom she must nurture and bring up. As far as children are concerned, the parents’ duty is to prepare them for life, for any trials that God may send them. While the parents are alive, the child will always remain a child for them and should treat his parents with love and respect.

The children’s love for their parents is expressed in complete trust in them. A real mother finds importance in everything in which her child is interested. She listens just as willingly to his adventures, joys, disappointments, achievements, plans, and dreams as other people listen to a romantic narrative.
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Philip Ngai originally shared:
 
Still looking for a replacement for my broken Samsung 305T WQXGA LCD. Repair seems impractical.

The Seiki Digital SE39UY04 39-Inch 4K looks tempting at a little over $400. Yes, it will be 30 Hz. But I don't play games.

http://www.amazon.com/Seiki-Digital-SE39UY04-39-Inch-Ultra/dp/B00DOPGO2G/ref=pd_sim_pc_2
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    MCCAIN: It was you and people on Fox that said in Libya, “We didn’t know who they were and let’s not help these people.” They had an election and they elected moderates. They rejected Islamists. And yes, there are al-Qaeda factors and there are extremists in Libya today, but the Libyan people are friends of ours, and they support us, and they support democracy. So you were wrong about — so you were wrong about Libya.

McCain either doesn’t know or doesn’t care who is in Libya’s actual government. His contention that the Libyans rejected Islamists is completely wrong. The “moderate” government coalition upholds Sharia and terrorism as part of its guiding statement and the election was of dubious legitimacy.

The “moderate” Libyan government and its security forces have been heavily infiltrated by Islamists, an admission that comes from within the government. Before the consulate attack, the Libyan Interior Minister refused to take action to stop the Salafi destruction of Sufi shrines and eyewitnesses testified that security forces were involved in the destruction.

The consulate safe house was betrayed from the inside, which again means that the Libyan authorities are completely unreliable. More so than the Iraqi authorities were.

The disturbing thing is that McCain doesn’t seem to know what is going on in Libya or how wrong he was about Libya. Even the attacks haven’t woken him up. He’s still pushing the same Springer line as if nothing had happened.
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One powerful example of the phenomenon "normalisation of deviance" he came across was the rash of crashes suffered by Korean Air Lines in the 1990s.

"Korean Air Lines in the 1990s was crashing at seventeen times the international average," Pellerin says. "It got so bad the president of Korea would not fly on Korean Air Lines. What's interesting about it is it went on for four years. Why did that happen?"

they were good technical people at KAL. "They kept testing the pilots… they're as good as pilots any place." Finally Boeing subsidiary Alteon put observers in the cockpits of KAL jets to find out what was happening. What they discovered, Pellerin says, was that the social context in which pilots were operating was having an impact on safety.

"There's only two people sitting there [in the cockpit]. The captain starts to make small mistakes and [because of the airline's internal hierarchy] the first officer is embarrassed to correct him, so he doesn't say anything cause it's considered impolite. Most of the time it doesn't matter. But as this goes on and on, the first officers just want to tune out.

So they're reading magazines while the plane's flying and the captain is all by himself screwing things up. And you know, modern jets are designed to be flown by two people working as a team… so they figured out the problem fixed it and the safety record immediately went back to international standards."
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The result of hard water. About 10 grains per gallon.
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OMG! Replace all the pipes to copper when you move into an old house that hasn't done so yet, save a lot of trouble later assuming you plan to live in the house a quite a while. (even though I was advised not to do so if it's still working.)
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Have him in circles
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  • Massachusetts Institute of Technology
    Electrical Engineering
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  • Commercial Real Estate
    General Manager, 2011 - present
  • Cisco Systems, Inc.
    Technical Leader, 1998 - 2011
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Fremont, CA 94539
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