In every Scrabble set, exactly one of the 100 tiles is a Z. The other high-value letters (one tile each) are Q (also 10 pts.), and J and X (eight points each).
More recently, nroff and troff have generally used Z and W to represent 10,000 and 5,000, respectively, so the largest number representable is 39,999 = ZZZMZCMXCIX instead of 3,999 as in Roman numerals as conventionally used in English today.
The government's main page is <http://www.gov.za/>.
Inoffensive data on South Africa is found in the factbook entry from the latest edition of the CIA Factbook
African Studies Center (at the University of Pennsylvania) offers a resource page. The Norwegian Council for Africa (NCA) has a Republic of South Africa page.
South Africa Internet Exchange (SAIX) says it built and ``owns the largest IP backbone infrastructure that connects South Africa to the world.''
ZBLAN, ZBLANP, and some other heavy-metal fluoride glasses (HMFG's) are of interest primarily as waveguides in the mid-infrared range. ZBLAN has a transmission maximum around 2.6 microns (vacuum wavelength) with a minimum loss of about 0.003 dB/m. The next-best choice (in terms of this parameter) among common fiber materials is single-crystal sapphire, with a minimum (at a slightly longer vacuum wavelength) above 0.1 dB/m.
And STAY out!
- A rare medical disorder. Vide hoofbeats.
- An official (umpire, referee, etc.) at a sporting contest. Vide four zebras and ten yards of chain.
- An animal that looks like a striped horse. The answer to the canonical question is: white with dark stripes, not the other way around. At least, the dark stripes pale and taper and leave a light-colored belly. The bongo, on the other hand, is reddish with white stripes. [The bongo is not in the Equus genus but in Boocercus -- an antelope.] An animal similar to the zebra, Equus quagga, had brown stripes covering the head and fore part of the body. It got its name from the Zulu word for stripe (kwag). See also okapi and blaubok.
You know, back in the days before dyes were invented, probably the only way to get an interesting-looking fur was to hop a jet to Africa and kill something unusual. That's probably why the quagga is now extinct.
One of the puzzles of biology is why certain animals or their bodies do apparently stupid things. For example, various male birds and insects make loud mating calls that increase their likelihood of becoming food; various species of birds and fish devote valuable nutrition resources to cultivating attractive plumage (think peacock) or coloration that is dangerous in the same way that camouflage is safe. More individual examples include the fact that when a lion approaches a herd of (say) gazelles, if one of the healthier males spots it he will jump up and down a couple of times to alert the group, instead of just getting a head start. This may seem like altruistic behavior, but altruistic behavior is ``selected out'' unless the animals helped share enough of the altruist's altruism gene. As it happens, the lion usually doesn't chase after the gazelle that wastes time jumping in place (echoes of the Matthew Principle). Another example is the time that my late friend Dean tried to knock down a lamp post and only managed to get a post-wide bruise across his body.
``Well,'' you're probably thinking, ``the answer is obvious. `The guy's always doin' it for some gal.' [It's in the Guys and Dolls script.]''
If you're not thinking this you should be. Take a moment now to think this if you have not already done so.
Good. Now this still leaves a question: why are female gazelles attracted to males that tempt fate (in the person of Mister Lion) instead of meek, responsible gazelles who majored in accounting? Recent research seems to indicate that the reason is, that's how they can tell they're strong and healthy -- in other respects that cancel the risk-taking behavior (either conscious or by their resource-wasting, pigment-splashed bodies).
Now you should be thinking (it's okay if you thought it before) ``This makes sense for peacocks -- pea hens are drab-looking. But what has this got to do with zebras? Male and female zebras both have stripes.'' Well, the answer (and it's been a while since I read about it) seems to be that often the females will use a dangerous trait for sexual selection, and the males won't, but the offspring both have it, and there you are. If it's not enough of a hazard to extinguish the species, the females can go on picking mates by comparing more and less hazardous versions of the trait, and the males can go on ignoring it.
I'm not sure if this really has anything to do with zebras, but what the hey. The quagga is now extinct.
One of the songs in the rock opera ``Hair'' has a lyric: ``There is a peculiar notion that elegant plumage / and fine feathers are not proper for the male / But actually / that is the way things are in most species.''
The sociobiological take on this is that females make a bigger biological investment in reproduction, so they're pickier about whose genes they share their reproductive resources with.
Sometimes the customs people at the border crossing in Niagara Falls would try to get you to read the letter out loud to see if you were really American or Canadian. That doesn't work as well as it used to.
The name Zener is used somewhat loosely here. High conductivity for reverse biases smaller than about 5V typically occurs by Zener tunneling, but higher-voltage ``Zener diodes'' have reverse turn-on voltage determined by the avalanche breakdown process. (Avalanche also leads to a sharper turn-on.)
Zener diodes are widely used in handy little investments called voltage protectors, surge protectors, or surge voltage protectors (SVP's, q.v.).
The simplest surge protector you can make is simply a pair of opposed Zener diodes in parallel across the power supply. When the voltage exceeds a threshold, this pair shunts the excess. (The threshold is the sum of the forward and reverse turn-on voltages.)
Duluth now has a sort of Zen connection. It has a sister-city relationship with Ohara, Japan. ``Ohara''? Maybe they thought it was in Scotland.
Anyway, as you've probably realized by now, the idea is to close the circuit through some resistance. Say the voltage source has a voltage V, and the unknown resistance (or known resistance, if you're just checking) is R. Then the current is I = V/R. Expressing what you want to find out in terms of the information directly available to the meter, that's
V
R = --- .
I
Notice that resistance varies inversely with the current. The fact is very obvious on the heavy old black VOM's like the Simpsons. The scales in ammeter mode are linear: on any given setting, the indicator needle turns through equal angles for equal current increments. Voltage measurement is measurement of current through a fixed resistance (the resistor is in series with the ammeter), so voltage scales are also linear. In resistance mode, one is still measuring current, but the scale is marked in the values of resistance implied by the VOM's voltage source. (If you like, it's a linear scale for conductance G = 1/R.)
One implication of this is that zero resistance corresponds to infinite current. This might be a problem, since real voltage sources can't drive infinite current, and real ammeters couldn't measure infinite current even if they could. This is only a theoretical problem, however, because the wires and probes in real VOM's don't have zero resistance. If we understand R to be the external resistance being measured, and r to be the combined internal resistance from probe tip to probe tip (including the internal resistance of the battery and the resistance of the ammeter), then
V
R = --- - r.
I
So zero measured resistance occurs at a finite value of current, namely Imax = V/r. There is a little problem with this: V is not fixed. As the battery in the VOM loses charge, V decreases by a few percent, and the scale is wrong. The solution to this is to change the sensitivity of the ammeter, so that Imax (whatever its value as V changes) corresponds to the needle deflection marked as zero resistance on the, uh, analog display. That fine adjustment in the ammeter current scale is controlled by the knob or wheel labeled Zero Adj or Ohm Adj or something.
I should probably shut up at this point, but I just can't help myself. There's a further little conplication. In the last paragraph I talked as if r were fixed, which is not quite true. The resistance of the ammeter is different on different resistance scales. A finer (lower) resistance scale corresponds to a measurement of larger current variations. This is all done with a single elementary ammeter, which has a single value of angular deflection for a single value of current. To measure higher currents, one uses a current divider. That is, one places a shunt resistance in parallel with the elementary ammeter. If the shunt resistance is smaller than the ammeter's by a factor of precisely 1/(K-1), then the measured current in the elementary ammeter will be only one Kth of the total current through the parallel pair. In other words, the meter display is scaled up by a factor of K.
One consequence of this is that in principle, the value of r depends on the scale, and the resistance zero has to be readjusted when the resistance scale is changed. Another reason the ohmmeter has to be rezeroed is that at higher scales, with lower ammeter resistance, the poor feeble battery that you refuse to replace has to drive more current, and its voltage decreases. (In other words, the battery's internal resistance increases as its charge decreases.)
The same mechanism for changing ammeter scale is used in the zero adjust: the zero-adjust knob fine-tunes the resistance shunting the elementary ammeter. So r isn't even sharply fixed at a particular scale. So look, it's never perfect. Do you really need to know that resistance to better than a tenth of an ohm? I should say that I've been using the present tense in this entry as if these old analog VOM's weren't obsolete, and also because I am the sort of obsolete person who actually has a few of these bakelite dinosaurs within reach as I type this. Modern VOM's (multimeters, also loosely called voltmeters) use op-amp circuitry and digital read-out, cost a pittance and don't need a zero adjust. Now what was the question?
Yes, it is now more useful, if it ever wasn't, to know more about zero-coupon bonds than about ohmmeter zero-adjust.
Back when I was young, which can't have been more than two or three years ago, a lot of the guys (it was almost only guys) who went into electrical engineering had played with electronic circuits as a hobby when they were in high school. They knew which end of a soldering iron was hot. They knew more advanced stuff too, like that you don't measure the internal resistance of a battery by putting an ohmmeter across it. Finally, they knew that if you measure the resistance of a resistor that's soldered on a circuit board, then you really measure its resistance in parallel with everything it is hooked to.
Nowadays, all that incoming EE freshmen know is C++, Java, and all that rot. I'm bummed.
You know, I have another tip that might be useful to anyone who found the previous paragraphs of this entry helpful: make sure you're measuring the resistance of a resistor. The ohmmeter is just a piece of circuitry. You close the circuit with a resistor, and it reads off a number that is the resistor's resistance value. If you close the circuit with something else, it may still read off a number that is the ratio of a voltage to a current, but that's no guarantee that you've got a resistor there. One way you notice that is by switching the ohmmeter probes. Passive devices (not counting leaky electrolytic capacitors) have resistance that is independent of polarity. Active devices generally do not. So if the two-terminal thingie has a very high resistance in one direction and a low resistance in the other, then it's probably a diode of some sort.
Getting back to the PCB context, if you think that the resistance you're measuring is just an isolated resistor, but you're not sure that the traces on the PCB don't go off and shunt the resistance elsewhere (you might have a doubt if the PCB is only partly populated), then switch the probes and check that you measure the same resistance. This train of thought, by and by, is continued at the zero-adjust entry.
It seems that this sense of ZFC is currently a ``laboratory phenomenon'' -- an abbreviation without an independent existence in the real world. Part of the reason may be that the expansion ``zero failure criteria'' is not understood. Therefore, as a public service, we explain it here. To have zero failure criteria means to have no criteria allowing one to say that failure has occurred. This implies that, by the book, no failures can be said to occur. On the other hand, it also implies completely lax and failed quality control, and therefore complete failure. Thus we have a failure situation that we can call ``zero [i.e., total] failure.''
Hmmm, it turns out the Germans do something like this as well. In fact, just as in English, they do it in a few different ways. Written out the long way, following the grammar rules of almost ordinary language (omission of the definite article before hands or Händen is a sort of formulaic business brevity), one can write ``zu Händen von Herrn Zuker,'' or ``zu Händen von Frau Schade.'' The preposition von (`of') takes a dative object, which requires Herr (`Mr.') to be inflected to Herrn. This is abbreviated, to take the first example, as ``z.H. von Herrn Zuker'' or ``z.H.v. Herrn Zuker,'' or ``z.H. Herrn Zuker.'' In the last form, the von is understood. One can therefore regard the von as part of the abbreviation, and for that reason I've included it in square brackets in the expansion above. That's not the only way to look at it, however. One also sees ``zu Händen Herrn Zuker,'' with the von simply elided.
You guessed it: The uranium ore (`pitchblende') can look like hardened pitch. See also the AnH entry. No, I won't tell you why. Just go.
The airport was built during the presidency of Ziaur Rahman, which began in 1975 and ended with his assassination in 1981. The airport was named after him shortly afterwards. It was probably a good move on IATA's part, to give it the geographically-cued code DAC. You never know when the reigning honoree might fall from favor. In fact, President Zia's widow, Begum Zia, is a former Prime Minister and currently leads the parliamentary opposition. In 1997, the opposition protested when the government proposed that the airport be renamed ``Dhaka International Airport.''
Just like IVF, but the fertilized egg (the zygote) is injected into a fallopian tube and takes the scenic trip to the uterus, instead of being inserted directly (as in IVF).
ZIFT is generally regarded as the most, um, intrusive ART. It is also the most expensive, and rather rarer than IVF and GIFT. GIFT is like unsupervised ZIFT: the gametes are dropped off at a fallopian tube and left to fend for themselves. In principle, therefore, ZIFT should be slightly more successful, but the difference is swamped by clinic-to-clinic variations.
Related entries: ST:NG, Z39.50.
What's this entry doing here? I thought I got rid of it yesterday!
Inoffensive data on Zambia is found in the factbook entry from the latest edition of the CIA Factbook
African Studies Center (at the University of Pennsylvania) offers a resource page. The Norwegian Council for Africa (NCA) has a Zambia page.
Learn more at its entry in WebElements and its entry at Chemicool.
The American Zinc Association has a site.
The following paragraph appears in ``How Tina Brown Moves Magazines,'' an article by Elizabeth Kolbert for the December 5, 1993, New York Times Magazine.
Brown is intensely aware of the criticisms of her work and even guides the conversation around to them at several points, prodding me to tell her anything negative I have heard. When I comply, she does not so much answer her critics as flatten them. When, for example, I point out that many readers, both professional journalists and ordinary subscribers, have told me they find her New Yorker more readable but less thoughtful and ultimately less memorable, she responds with a breezy putdown: ``I think that's a kind of fakery. There is a kind of snobbery about `Oh, you should have seen the south of France when it was a fishing village.' The 50,000-word piece on zinc -- did anyone really read it?''
She has some admirable talents, but they don't do much to account for the great run she had. She had a string of successes as the editor of various high-brow magazines that she made more, uh, accessible. She charmed a small number of powerful men in the business, and terrorized a large number of subordinates. She generated a lot of commercially valuable buzz. Then she launched Talk magazine in 1999. It was a good magazine and a spectacular failure, and since it folded in 2001 the world of print journalism doesn't seem to have had any attractive opportunities for her to pursue. Oh yeah, she writes a weekly column for the Washington Post and hosts the talk show ``Topic A'' on CNBC. Did anyone really watch CNBC?
Okay, here's my contribution, since the Z's are really very thin:
One time that my great uncle Fritz was testifying in an American court as an expert witness on German law, his credentials were challenged on the grounds that Germany is governed by ``Roman law.'' [The objection is a silly one, since most of the continent is governed by some local variant of Roman code.] He replied simply that his degree was ``Doctor of German and Roman Law.''
``Uncle Fritz'' was a grand uncle and a great uncle, and he was a granduncle and a great-uncle (also ``great uncle'') of mine, so it follows that he was a great granduncle. From this one might draw incorrectly the correct conclusion that I have first cousins once removed.
The most interesting thing uncle Fritz ever told me about his university years was the attitude among his classmates in advance of the World War (WWI). They all scoffed at the notion that there could be another major European war -- they supposed that Europe was too civilized, by that point in history, to descend to such barbarity...
Once I noticed some United Nations (UN) documents on Uncle Fritz's bookshelves. When I pointed them out, he remarked that they were written on very good paper.
Unlike any other bank in the world, the Zebu Overseas Bank invites you to invest in a Zebu, the hump-back cattle of Madagascar. Your Zebu will be placed with a Madagascar family to either provide milk, work the land, produce calves or pull a wagon.You will be the owner of a Zebu. It will be regarded as a direct, working investment in our economy rather than a financial gift.
Your investment gives you the right to open a Zebu Saving-Bank Plan (Z.S.B.P.) giving interest on savings.
If anthrax becomes a big problem, Zob derivatives might be interesting: sell the hump-back cattle short.
The ZOB is often found on Bahnhofsstraße. Gee.
bears with furniture.
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An old joke:
Circe was a mighty sorceress who had the power to change men into swine.
This was a very dirty trick, because ever since then, millions of women
have spent countless hours in a vain attempt to change them back.
There's a small academic industry dedicated to proving theorems without using the axiom of choice that were originally proven using it. There's no Axiom of No Choice in most zoological gardens of mathematical beasties. There's just math with the axiom and without it.
The STAFF entry mentions an instance of zero-point fluctuations.
For the thirty-one years preceding, the country had been ruled by Mobutu Sese Seko et cetera, the world's most famous and avaricious kleptocrat, particularly when you normalize the theft to the national product, if any. [Technically, it's a (mineral-)rich country. We have a somewhat newsy entry on one of the minerals -- coltan.] The renaming to Z&uïre was part of an ``authenticity'' campaign that began in 1971. (For more on the name changes, follow the Mobutu Sese Seko link.)
Here's a page on Zaire from City.Net. Here's a color map. Here's a bigger, less colorful, more detailed map, scanned in complete with paper crease from the CIA map, which is considerably less irritating than that picture eczema that's called watermarks. Water damage, more like.
Kinshasa is the capital. (Its name was not returned to the earlier Leopoldville.)
Hmmm, now that Mr. Kabila is no longer very useful to his former supporters, his Rwandan troops have gone home, things have haven't looked so good for him. Oh, wait! Good news for Mr. Kabila: a rebellion against him begun in early August 1998, very successful in early days, led by Tutsi. Maybe ethnic pride and resentment will save him. Or maybe he'll just fall.
Newt Gingrich (Speaker of the US House of Representatives for a while, R-Ga., widely credited for the Republican takeover of the House in the 1996 elections) did his doctoral dissertation at Tulane (History, 1971) on ``Belgian Education Policy in the Congo, 1945-1960.'' (The country gained independence in 1960.) You could order it from University Microfilms.
Inoffensive data on DR Congo is found in the factbook entry from the latest edition of the CIA Factbook
African Studies Center (at the University of Pennsylvania) offers a resource page. The Norwegian Council for Africa (NCA) has a Congo-Zaïre page.
Laurent Kabila was murdered in January 2001, and succeeded by his son Joseph (estimated to be the philandering Marxist's eldest). Within months, he has made Western diplomats cautiously optimistic. After a century of autocrats Belgian and home-grown, one dares not hope, but one dares not not hope.
Oh, great, Mount Nyiragongo erupts in January 2002, displacing half a million people and not completely destroying the country's central trading city Goma, still in the hands of anti-government rebels. Residents return to the city before the volcano quiets, not feeling safe (from Rwandans) in UN camps. Just another disaster. It would be a comedy if it weren't a tragedy. In fact, it's been a famous novella. In 1890, Joseph Conrad went into the Belgian Congo to work as a steamship captain, and came out with Heart of Darkness in 1902.
Let's have more about Laurent Kabila's alleged progeny. According to another work of fiction (some 419 spam I received today), I am to understand that an illegitimate half-brother of Joe Kabila is Emmanuel Kishali Kabila. Following up (hey, it's investment research!), I found ``just one more collection point of close to 2000 Nigerian Advance Fee Scammer names which have been compiled.'' On the page of names K-L, Kabila is the only surname with, for convenient reference, given names subdivided into sections (three: A-L, M, N-Z). The other Kabila names beginning in E are Eddy K. Kabila, Edward Kabila, Ejike Kabila, and Elvis Kabila. The only other name to be similarly subdivided was Williams (though that was fortified with William names). (It should be conceded that there were also sections in separate tables for Mobuto, Sese and Seko.) The only personal image on the entire K-L page was ``Titi Kabila although the file name was originally edith.jpg.''
An alternate spelling and pronunciation of zurf is zarf. Zurf and Zarf sound like twin lead characters in a cartoon about the daily grind of living on planet Erf. But zarf is recognized as a real word by the OSPD4, whereas zurf isn't. Oh sure, that sounds minor, but if you were a word you wouldn't laugh. To a word, that kind of endorsement can mean the difference between appearing on movie marquees and being scratched out on a cheap notepad and going to bed hungry.
Back during the civil war, there were a couple of different liberation movements. People in the West often had difficulty distinguishing the two -- ZAPO and ZANO, or something, I think they were called (for Zimbabwe African People's/National Organization, vel sim.). They seemed to differ mostly on the basis of leadership personalities. In fact, the main difference was ethnic: the smaller older (ZAP) organization had an Ndebele leader (Joshua Nkomo) and mostly Ndebele following, and the larger organization (ZAN) had a Shona leader (Robert Mugabe) and majority-Shona following.
In the first elections of the postwar period, voting for the guerrilla-organizations-turned-political-parties observed the same division, and Mugabe became president. Mugabe has made some efforts over the years to create a unity government, including naming Nkomo to an evidently ceremonial/advisory rôle (Co(!)-Vice President) in every government. Now seats in the unicameral legislature (House of Assembly) are filled by direct vote. Almost all the seats are ZANU-PF.
This one-party business does not bode well. Is this one of those nation-wide deals, where a large minority is disenfranchised by the technicalities of ``district-wide'' voting? I don't know, I haven't been following the story. Neither have US news media. After Rhodesia became Zimbabwe, the action moved to South Africa, and by the time South Africa moved to majority rule, the cold war was cold and dead in its grave, good riddance. The Marxist and Marxist-sympathetic leaders of African countries discovered that development rubles had dried up and quickly became converts to the virtues of a mixed economy. This story has been repeated.
Harare, the capital, is in Mashonaland.
Inoffensive data on Zimbabwe is found in the factbook entry from the latest edition of the CIA Factbook
African Studies Center (at the University of Pennsylvania) offers a resource page. The Norwegian Council for Africa (NCA) has a Zimbabwe page.
The Stammtisch has been visited from the University of Zimbabwe.
At geocities, Thomas Scherrer maintains a Z80-Family Official Support Page.