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These items are an archive of past Topical Smorgasbord items that have appeared on the RF Cafe homepage. In keeping with the "cafe" genre, these tidbits of information are truly a smorgasbord of topics. They all pertain to topics that are related to the general engineering and science theme of RF Cafe.
now you have probably seen the headline from Wednesday evening about 26-year-old Massachusetts terrorist
Rezwan Ferdaus' plans to use radio controlled aircraft and a small clan of fellow terrorists to attack the
Pentagon and U.S. Capitol. According to reports, the PoS, who precisely fits the description of a White,
right-wing Christian extremist as published by Homeland Security as being the most likely to fit their
domestic terrorist profile, had
purchased what he thought was 25 pounds of C-4 explosives, three grenades and six fully-automatic AK-47
assault rifles (see
report). Fredaus also had a ready-to-fly F-86 jet model airplane delivered to a warehouse, ostensibly for use
as a delivery means for the C-4. As a life-long aircraft modeler, I am very familiar with that type of model.
It is made entirely of styrofoam and uses an electric ducted fan for propulsion. With only a 34" wingspan, 256
in2 of wing area, and a normal flying weight of 54 oz (about 3-3/8 lbs), the wing loading is great
enough to require a fairly high airspeed to maintain level flight. The ducted fan unit's 2.8 lbs of static
thrust is obviously high enough for an unladened model, but if even one pound of C-4 (and required triggering
mechanism) was added, the airplane would probably never get off the ground, much less be capable of flying
What's the big deal? So Taylor Wilson pulled off his first nuclear fusion reaction at age 14 (officially the youngest person ever to do it), and designed a patent-pending fissile material detector at age 15? Haven't we all done that, or something like it, by the time we were old enough to drive? News reports act like it's some major accomplishment that Taylor has a fully equipped nuclear laboratory in his home, and has access to the University of Nevada's physics lab space. Just because the lad has compiled a collection of nuclear material that would make Iran's Mahmoud Ahmadinejad jealous, you would think he was something special. All Master Wilson did, beginning at the ripe old age of 11, was purchase (using Christmas and birthday money) commercially available products that contain various sorts of radioactive material and then extracted it for the quantities needed to conduct his experiments. Photos on his website show transuranics, radioluminescence devices like glow-in-the-dark watch dials, fission products, radioactive vacuum tubes, low grade uranium and thorium samples, and smoke detectors, to mention a few sources. Heck, we've all had a watch with a glowing dial. So what if he collects historical <more>
A Logic Named Joe -
As a long-time Paul Harvey fan, I used to listen to his radio news broadcasts and especially looked forward to his "The Rest of the Story" pieces. It was a challenge to listen and try to figure out who or what the alluded-to person, place, or thing at the end of the the story would be. In honor of the recently departed Mr. Harvey, this week's Smorgasbord is fashioned after his trademarked style. An article in the September 2011 Smithsonian magazine inspired the research.
Born in 1791, the son of a New England Calvinist pastor, Sam was one of three surviving children out of
eleven born to the same mother. Early in life he developed an interest in writing, drawing, and painting. His
talent became obvious to all who would witness his efforts. The family's strong religious principles were
reflected prominently in his writings and artwork, but rather than follow in his father's footsteps as a
minister, Sam's passion for art led him on a journey to find a place of acceptance amongst professional
practitioners of the craft. His father's influence on him was not limited, however, to just Heavenly
endeavors. You see, Sam's father practiced a side vocation as a geographer, involving precision instruments of
measurement and copious amounts of detailed note taking <more>
Here we are on the eve of the 10th anniversary of the terrorist attack by radical Muslims on the World Trade center buildings, the Pentagon, and United Airlines Flight 93. It will not be until September 12th of this year that the official 9/11 Memorial at Ground Zero will be opened in NYC. The hole-in-the-ground waterfall required some clever optimization algorithms in order to squeeze in the 2,983 names that will appear in scrolling fashion along the perimeter. "The project was to design an algorithm for placement of names on the 9/11 memorial in New York City. In architect Michael Arad‘s vision for the memorial, the names were to be laid according to where people were and who they were with when they died – not alphabetical, nor placed in a grid. Inscribed in bronze parapets, almost three thousand names would stream seamlessly around the memorial pools. Underneath this river of names, though, an arrangement would provide a meaningful framework; one which allows the names of family and friends to exist together." Read all about the impressive solution. Why take so long to do anything? Maybe the planners were hoping by delaying it they would be able to have a joint ceremony with the proposed - and probably inevitable - mosque that is vying to be built alongside it. Thank your elected non-leaders.
Even though Google's company motto is, "Don't Be Evil," a lot of people think some of their privacy violation practices are somewhat less than heavenly. To paraphrase Thomas Jefferson, "Those who would give up Essential Privacy to purchase a little Temporary Search Results, deserve neither Privacy nor Search Results." Ok, that's a stretch. Love them or Hate them, Google undeniably has the best search engine available, and many of the other search engines buy database access from Google for their websites. Google is constantly experimenting with new ideas, and one, which has been around for a long time, is the Google Scholar search. With it, you can automatically retrieve results that are restricted to scholarly sources like universities, the IEEE, legal documents, standards organizations, research centers, etc. Furthermore, you can narrow your search to specific areas of specialties like Chemistry and Material Science; Engineering, Computer Science, and Mathematics; Business, Administration, Finance, and Economics; and others. Sure you can probably write your own query to get the same results, but why would you? Give it a try - "Stand on the shoulders of giants."
Buried Riches - Rare Earths & More.
Have you heard about this? I hadn't. If you think the only goal in Afghanistan is to stamp out the Taliban, think again. An article in the October 2011 issue of Scientific American details the extensive mineral surveys that have been carried out there in the last year or so. Afghanistan is home to what may be the largest cache of rare earth elements in the world, with a potential to replace China as the largest extractor (~90%) of those atoms that lie in the lanthanide and actinide regions of the periodic table - the two rows that are typically pulled out of the chart. China, you may have heard, is severely restricting the export of rare earths - wanting to keep it for themselves - thereby triggering a near panic. Prices are rising so alarmingly that reopening mines in the U.S. has once again become profitable in spite of the crippling regulations that years ago closed down operations here (huge loss of jobs and tax revenue) and forced us to become reliant on offshore supplies - just like what is happening today with oil and gas, BTW. There are a lot more than rare earth elements available, though. According to a map published with the article, there are equally large reserves of copper, lithium, tin, lead, zinc, gold, silver, tungsten, <more>
It's that time of year again when balmy summer days are yielding to chilly autumn evenings, the kids are back in school, coats are on the racks in stores, and the college rankings are being published. U.S. New & World Report just released their findings of top colleges for 2010. You don't even need to read the article to guess that Harvard, Princeton, and Yale occupy the top three spots overall. The owners and editors (and their families and social circles) are affiliated with those institutions, so of course they will rank highest. You and I are more interested in the engineering school rankings - where real educations are had. MIT is in the #1 spot, followed by Stanford and UofC-Berkeley. Cornell and Purdue tie for #9. My alma matter, University of Vermont, places at an embarrassing #82 for overall ranking. It could have been worse, though; UofNC-Charlotte came in dead last. According to USN&WR, while the national unemployment rate hit 9.8% in 2010, it was only 5.4% among those with bachelor's degrees. Also, those with at least a Bachelor's degree earned on average 75% more in their lifetimes than those with only a HS diploma. Results are based on peer assessment surveys.
Mechanical clocks have been around for about a thousand years, and are thought to have had their origins in China in the form of water clocks. From there, mercury-driven escapement mechanisms were developed that greatly reduced the size and improved accuracy. Pendulum- and spring-driven escapements further reduced the volume requirement to where pocket and wristwatches were possible (via spring, not pendulum) by the end of the 19th century. Exact dates and names are hard to verify. Electronic clocks using crystals and then nuclear clocks using hyperfine transitions of atoms pushed accuracy and stability into the quantum mechanical realm. Fine clocks all, but none of them will last forever. Amazon founder Jeff Bezos aims to change that with his 10,000 Year Clock, saying, "In the year 4000, you'll go see this clock and you'll wonder, 'Why on Earth did they build this?'" Currently being assembled deep inside a Texas mountain, the Long Now Foundation and its team of designers and builders have made incredible progress. Few people are able to dedicate their lives to such a solitary task, in such a challenging environment. Read through the descriptions and watch the videos of how this project is being executed. It is utterly amazing!
has been a test of the Emergency Broadcast System. Had this been an actual emergency, you would have been
instructed where to go in your area for additional instructions." Do you remember back when you would be
All in the Family and suddenly a shrill tone constituted of a combination of 853 and 960 Hz sinewaves
would blast through the television's speakers, accompanied by these bars flashed onto the screen? It was
implemented in 1963 as a means of alerting citizens to current or potential critical events like a pack of
Ruskie ICBMs flying over the North Pole, an invasion force landing on American shores, or a mile-wide tornado
ripping a path through the Badlands of South Dakota. "The Emergency Broadcast System was established to
provide the President of the United States with an expeditious method of communicating with the American
public in the event of war, threat of war, or grave national crisis," so goes the official line. The
EBS, successor to CONELRAD, could be used for national or local emergencies. Radio and TV stations were
required to broadcast the test at least once per week. When an actual emergency did occur, a teletype message
was sent to affected areas that was specially coded to trip an audible alarm in the studios. Broadcasters then
initiated a procedure to interrupt the current show, play the, <more>
Electronics Weekly just published the results of their UK 2011 Salary Survey. A sample size was 1,160 engineering professionals found that in 2011 the average yearly salary for someone working on the UK electronics industry was £44,161 ($67,739). Evidently the average electronics worker looks like this: Male, aged 47, earns £44,000, had an increase of 2.6% in his last pay review, and is expecting a 2.2% increase next time, works in the South East for a firm with 1,331 employees and has worked there just under 9 years, has worked in the industry for 17 years, works in design / development engineering for a company in the aerospace / military / security sector, keeps an eye on the jobs market, and uses a mobile phone with Internet access.
You probably read recently of the San Francisco's Bay Area Rapid Transit (BART - good acronym, as in Simpson) shutting down cellphone service in order to thwart a rumored attempt to organize a flash mob attack. 1st Amendment groups have sued BART over the action. Also in the news has been the government's plan for being able to shut down the Internet in the event of a national emergency (defined as whatever they need it to mean). We already know that Big Brother has the capability to universally control both wired and wireless phone service. OnStar-equipped vehicles have been shut down remotely by law enforcement. It all seems very Orwellian, but it began before the publication of "1984" (in 1949). Did George just dream up the book's theme of total government control and a lemming populace, or did it come from astute observations of past behavior that was projected into the future? On December 8, 1941, the day after the Japanese attack on Pearl Harbor, the FCC issued a "Notice to All Amateur Licensees" that began thusly: "All amateur licensees are hereby notified that the Commission has ordered the immediate suspension of all amateur radio operation in the continental United States, its territories, and possessions." <more>