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Comment: Re:Good luck with that (Score 1) 219

by jfb2252 (#47523047) Attached to: China Plans Particle Colliders That Would Dwarf CERN's LHC

Go to http://directory.web.cern.ch/d... Click on ATLAS and CMS, and find the directory of institutions. China is well represented on both. You may also scan the lists of 3000+ collaborators each, of course. China is also represented in detector collaborations at many other labs worldwide, including mine.

When I last checked the price for a ROXIE license from CERN was 2500 Euros, SC magnet design software incorporating all they learned about magnetics and mechanics.

I was involved in the SSC magnet project 25 years ago. Most of the difference between the SSC and LHC magnets is 4.5K planned operation of the former and 2K operation of the latter. Had LHC chosen to develop NbTiTa conductor they might have gotten another 15% in energy capability. This is old technology.

I spent two years working on Nb3Sn wire and tape magnets before my SSC work. At one point I hoped ITER would move along fast enough to push Nb3Sn magnet development for accelerators. Conductor yes, magnet technology not in time. Since China has great ceramic expertise, they may do better than Western metal-bashers.

Comment: Re:Good luck with that (Score 1) 219

by jfb2252 (#47518887) Attached to: China Plans Particle Colliders That Would Dwarf CERN's LHC

The 240 GeV is related to the Higgs mass, not the maximum energy possible in the ring. They could increase the center of mass energy to over 350 GeV in the ring and create top-antitop pairs.

However, the diameter is really set by the proton energy desired for the successor machine and the superconducting magnets they expect to be feasible when that machine is built. China builds MRI magnets with NbTi now so they already have most of the cryogenic technology needed. No one can yet build Nb3Sn magnets required for the desired proton machine. Or for the LHC energy upgrade.

The LEP magnets were mostly concrete. Fields were so low the amount of steel and copper needed was tiny, so these active materials were spaced out with concrete. Shrinkage over the course of construction caused some hiccups in the earliest days of LEP.

As another commented, the Daya Bay neutrino detectors are quite sophisticated. China is also working on GEMs. They make excellent scintillators.

Comment: Re:Infectious diseases ... (Score 1) 493

by jfb2252 (#47123857) Attached to: Mutant Registration vs. Vaccine Registration

I am 62. I had mumps, measles, chickenpox and rubella (twice) as a child. I was given both Salk and Sabin polio vaccines, and smallpox at least twice. I have kept DP up to date and wish I could still get DTP (vs DTaP). Do I have records of any but the last? None beyond whatever antibodies remain in my blood and the smallpox vaccine scar on my arm. I'd guess at least half the US population is in the same situation. Countries with sensible health care systems are a different matter.

Comment: Re:Been saying that...Wrong, Simply Wrong. (Score 1) 376

by jfb2252 (#42811141) Attached to: Economists Argue Patent System Should Be Abolished

There is a difference between medical devices and pharmaceuticals. MRI and CT would likely have developed in the way they did without patents because the capital requirements for practical system design and manufacture are so large. FONAR, the first MRI system, died in spite of its patents. GE, Siemens, Phillips had the capital to make it practical and cost effective. For MRI, the key advance is the pulse sequence discovered at Univ. of Aberdeen by Bill Edelstein and others. http://en.wikipedia.org/wiki/William_A._Edelstein/ When I was in the business in the mid-80s, pulse sequences weren't patented and the capabilities of MRI systems were increased enormously year to year. CT scanners also require large capital. I believe there are sufficient barriers to entry for medical imaging to eliminate patents.

Surgical procedures weren't patented until recently. Medical devices which one or a few people could invent fall in a grey area in my mind, because the barrier to entry is small as the poster wrote. OTOH, Kearns and the intermittent wiper showed that patents aren't a barrier to abuse of the small inventor.

For pharmaceuticals, requiring generic firms to conduct their own safety checks within a decade of introduction of a new drug would likely suffice as a barrier to entry for the discovers.

Comment: VA voted first thing (Score 1) 821

by jfb2252 (#41897413) Attached to: U.S. Election Day In Progress: What's Been Your Experience?

Given the change to standard time it was easy to be at the polling place half an hour before it opened. I was seventh in line. When the poll opened there were about fifty in line. I had checked that everything was OK with my March 2012 registration change in early September so I didn't have any trouble, unlike the earlier commenters. Why the legislature thinks reciting a name and address out loud is a fraud deterrent I'll never know.

Comment: high temp superconductor receivers (Score 2) 615

by jfb2252 (#41723725) Attached to: Ask Slashdot: Why Does Wireless Gear Degrade Over Time?

I haven't been to an Applied Superconductivity Conference for a decade, but at that time people were beginning to sell racks of very narrow band receivers for cell systems with high temperature superconductors allowing a narrower bandwidth than anything one can do at room temperature. Sterling refrigerators at 80K. One was able to increase channel density about a factor of three. I don't think this technology has made it to consumer electronics yet. Or will.

Comment: analog transistors age (Score 5, Insightful) 615

by jfb2252 (#41723103) Attached to: Ask Slashdot: Why Does Wireless Gear Degrade Over Time?

This is a hypothesis based on peripheral involvement with analog and digital RF at 0.5 and 1.5 GHz for twenty years.

AFAIK, the output stage of anything broadcasting above about 2 GHz has to be analog, with the lower frequency signal mixed into a carrier at the higher frequency. Digital synthesizers and chips which can deal with 1.5 GHz directly are still very expensive and are unlikely to be used in the consumer routers. So the final output stage is likely an analog RF transistor.

Analog transistors change characteristics with age at elevated temperature, where elevated is anything over 20C. Implanted ions diffuse with time and temperature, changing junction characteristics. The small structures required by high frequencies are more sensitive to such things.

Comment: JPL's list of future Earth impact risks (Score 1) 412

http://neo.jpl.nasa.gov/risk/

Sentry Risk Table

The following table lists potential future Earth impact events that the JPL Sentry System has detected based on currently available observations. Click on the object designation to go to a page with full details on that object.

Sentry is a highly automated collision monitoring system that continually scans the most current asteroid catalog for possibilities of future impact with Earth over the next 100 years. Whenever a potential impact is detected it will be analyzed and the results immediately published here, except in unusual cases where an IAU Technical Review is underway.

Comment: stop human space flight funding (Score 0) 71

by jfb2252 (#39017787) Attached to: NASA Considers Privatizing GALEX Astrophysics Satellite

The budget for human space flight is more than thrice that for science. NASA is going to spend over $20B on the "new" SLS system for two launches through 2020. NASA must withdraw from two joint Mars missions with ESA because its science budget is being cut $300M and the Webb telescope went over budget. The fact that Webb went over budget because Congress didn't provide timely funding is rarely mentioned; Congress simply blames the agency.

Comment: Re:Try the JMP demo (Score 1) 146

by jfb2252 (#38079466) Attached to: Ask Slashdot: Statistical Analysis Packages For Libraries?

I agree whole-heartedly. I've been using JMP since version 2.0. Great for exploratory data analysis. SAS differentiates it from SAS proper by limiting the data sets it can deal with to RAM, but with 4GB of RAM common these days that's not likely to be an impediment.

Almost twenty years ago I compared the sort routine in JMP to Excel's. 30K rows, 28 columns, sort on 3 columns. JMP took about 1% of the clock time Excel did.

Academic pricing is pretty good.

Make sure your code does nothing gracefully.

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