Friday, November 25, 2016

Long-lasting designs

This is a reply to a post on YouTube discussing the longevity of Miranda-class ships in the fictional Star Trek universe.

Long-lasting old designs in various complex technology branches is really nothing new.

wrt this and the car industry, then off the top of my head, I can cite as examples the Volkswagen Beetle (1938–2003, 65y), the VW microbus (1949–2013, 64y), and Citroën 2CV (1948–1990, 42y).

Fiat 124 (1966) was transmogrified into Soviet Zhiguli/Lada cars, production of which design ended in 2012 in Russia, but continued well into 2014 in Egypt. With 2014 in mind, that's 48 years of mostly continuous production, though in that same year of 2014, the plant in Egypt had a fire

With trams, it's the PCC Streetcar (1936), numerous modifications of which are still in service. I don't know, whether any new PCC-spec trams are still built.

The Boeing B-52 Stratofortress had its first flight in 1952, and these planes are still in service.

Saturday, November 12, 2016

Most supernovae are misclassified as nebulae...

...Because the calculations reflecting the speed of light en route to Earth are off, since they don't take into account the effects caused by the confluence of time dilation and dark matter across the long trip that the photons take.

The title refers to numerous photos of nebulae, which I think are really supernovas in progress. I attribute this misclassification the the sheer distance involved and what I think are inaccurate speed-of-light calculations, because the distance between an event and Earth is so great. So, even a quick event in a galaxy far, far away just appears to happen very, very slowly when viewed from here. — So slowly for that matter, that the event looks to be in a standstill.

Dark matter, black holes, and other crazy theories

What I think dark matter is

Dark matter, in turn, is gravity from black holes (aka singularities) not (yet) manifest in this realm. These black holes are singularities, but not black holes, because they haven't opened up yet, but are close enough to the 'wall' separating them and this universe to cause gravimetric emissions. Alternately, I can describe dark matter as just a gravimetric echo of a black hole not yet manifest.

Imagine putting small magnet pieces on paper and then moving them around using a big magnet on the other side of that sheet of paper. The sheet of paper is that wall.

The black holes themselves don't open up just like that. A typical process in the lifetime of a manifest black hole is first to collect enough matter. And well, if there's no matter, then the singularity won't bother either.

But — if there's enough matter, the gravity of the non-manifest black hole (the 'dark matter') will collect the matter together. The right elements that are easier to attract will congregate into one or more masses, of which one such mass is large enough to be solar-forming.

The catch is, that black holes rotate, and the solar material basically chafes at the fabric of the 'wall' separating ths realm from what is probably another one. One possibility is, that a certain small amount of solar material moves from this realm through an inner back hole (inside a sun) to the other side. Well, enter pulsars. Some pulsars are long-lasting and stable, but emit solar material from the other side transmogrified into very powerful pulsar emissions.

Now, the stars and the suns are just pimples of the universe, which are mostly stable. In some cases, a star runs out of fuel (collected matter) and becomes a dwarf.

In other cases, there is some kind of an imbalance that causes a supernova to happen.

An open black hole sucks everything in; imagine a drain, and water going through it is just space. But in space, it's totally 3-dimensional. |There might be more dimensions.|

For a supernova, one option is, that as the amount of solar material increases, a black hole within the stellar object gets more powerful (and maybe sucks more in). Or that it is sustained, along with the star around it. Once the stellar object runs out of fuel, the opening of the singularity inner to the stellar object cannot be sustained, and as that singularity leaves its 'nest' and closes within the stellar object, the remaining solar material that has so far made up that stellar object — unable to be to be sucked in anywhere — disperses. Often violently.

Imagine a rubber balloon and then applying pressure from its hind end. Apply too much pressure, and the ballooon pops. The rubber pieces of the balloon fly around quickly and sometimes violently, as they hit stuff in their way.

13.11.2016 update.

I later thought about actual open black holes that don't have any light around them. As I'd described stars as pimples of the universe, then I could think of not just one type of supernova, but more than one.

So, one type of supernova is likely to be caused by dispersing solar (and other) matter once a singularity has closed up, but the collected matter around the closing doesn't have anywhere to move. That's described above. To add to that, such a nova happens, if the closing is not safe, or if there's surplus material and gravity, and maybe an imbalance involved, but the hole itself closes.

The other type of supernova is caused by a tear in the continuum. The magnets and paper description might come into play here, as rotating black holes are covered by stars (note, that manifest singularities are circular, but instead of forming a mass, they are 3D drains when open), which avoid, prevent or delay the tear from happening.

So it could be, that a certain star runs out of fuel, but a greater imbalance causes the black hole to manifest.
What may be causes to the imbalance, are unknown. Perhaps lack of sufficent matter to close the hole, if the singularity is too powerful. In that case, it's not so much solar matter exploding outwards, but a violent opening, whereby normal gravity is pushed away, in the process also pushing outwards, but not destroying/extinguishing all extant matter that is in the way. That is disperesed before the hole opens.

At this point, I'm too tired, and the previous paragraph is too illogical even to me. I'd rather read up on Wikipedia about actual discoveries and proofs, but later.

All this from the crazy theories dept. I felt so giddy this hour, that I wanted to put out something off the wall with lots of non-sensical technobabble.

Added minor wording and idea updates a few days later.

Saturday, November 5, 2016

Postimees ja vana Android

See on (algselt kiirena kirjutatud) täiendus varasemale postitusele, mis kritiseeris Postimees Online (edaspidi PMO) uue mobiiliversiooni kasutatavust, kus peamiseid kriitikanooli sai sisu liigtihe automaatne uuestilaadimine.
Üldse, kui sinu hallata on suure levikuga veebileht, siis üks suuremaid vigu on [kogu] lehekülje sisu automaatne uuestilaadimine, sest kasutaja pole seda ise soovinud, ning mobiiliseadmetes kulutab see akut.
Antud blogipostitus on mõeldud kõigile neile inimestele, kelle mobiiliseade (telefon või tahvelarvuti) on varustatud Android 2.3 "Gingerbread" opsüsteemiga, mida pole võimalik uuendada, ning mille vaikimisi lehitseja on liiga vana ja aegunud, et oleks võimalik Postimehe veebilehelt mugavalt uudiseid lugeda. Või üldse.

Ehkki seesinase fookus on Postimehe koduleht, võimaldavad allpool pakutud lahendused laiemalt külastada teisigi kaasaegseid Interneti-lehekülgi, mis Androidi (2.3 ja vanemate) vaikimisi lehitsejas ei näita või pole enam toetatud.

Juhised nõuavad mõnetist tehnika-alast oskust, kuid leian, et instruktsioonides ei tohiks midagi väga keerulist olla.


Probleemid:
* Android 2.3 on vana ja Postimehe enda äpp võib-olla näitab, võib-olla mitte, aga tegemist on äpiümbrisega (wrapperiga), mis põhimõtteliselt näitab Postimehe kodulehte sisseehitatud vaikimisi veebimootoriga. Postimehe äppi pole tegelikult vaja.
* Android 2.3-s vaikimisi lehitseja on liiga vana, et kogu seda sisu adekvaatselt näidata, sest selle lehitseja umbes viis aastat vana veebimootor on lootusetult aegunud.

Mida teha:
* Tõmmata peale Firefox Androidile.
ARMv7l protsessoriarhitektuuril käiatava Android 2.3 jaoks on kõige uuem Firefoxi versioon 47.0; selle eestikeelse variandi saab tõmmata Mozilla FTP lehelt või Google Play Poest.

Mozilla enam ei arenda Android 2.3 jaoks Firefox-i, nii et Google Play Poes võib Firefox olla vabalt märgitud kui ühildumatu. Siis tuleb tõmmata Firefoxi APK-installer eraldi Mozilla FTP-lehelt ja enne selle installimist lubada ajutiseks Androidi seadetes kolmandatest allikatest installimise võimalus ehk mitte-Marketist/Play Poest.

Asja parem külg on see, et vanale mobiili-opsüsteemile siiski on saadaval modernne lehitseja, millega saab vaadata kaasaegseid veebilehti.
* Et PMO mobiiliversiooni sisu laeb liiga tihti, tuleb kasutada PMO töölaua-versiooni. Viimases töötab siis ka artiklite kommentaaride hindamise funktsioon. Ehkki Firefoxi äpi-menüüst on võimalik valida "Töölaua-versioon", tekib ikkagi kaks probleemi:
** PMO lehtede jaoks tuleb Firefoxi töölaua-vaadet valida menüüst iga kord peale Firefoxi käivitamist või peale lehitsejas uue vahekaardi avamist.
** Teiseks on PMO töölaua-versiooni küljendus mõeldud töölauale, aga kunagi töötas see väga ilusti mobiiliversioonina. Vaadet on võimalik näppudega suurendada. Need liigutused on tüütud ja ajakulukad.

Lahendused:
1. Oletades, et sinu Firefoxi versioon on 47.0 (nagu üleval kirjas, Android 2.3-le kõige hiljutisem), jäta allolev vahele ja mine edasi järgmisele punktile.
Kui sa oma Firefoxi versiooni ei tea, otsi see üles: Lähed Firefoxis about: lehele, kus see kribukirjas näha on. Jäta see versioon meelde; tähtis on see kujul 47.0 (täisarv-punkt-null).

Ise kasutan Firefoxil põhinevat IseCat lehitsejat; Android 2.3-le on IceCat-i uusim versioon 38.8.0.
2. Edasi tuleb minna aadressiriba kaudu lehele about:config — seal on kõik Firefoxi tähtsamad seaded, mis on käsitsi seatavad;
1.1 puutuda seal suurt pluss-märki ja kirjutada nimelahtrisse

general.useragent.override.postimees.ee

1.2 Puutuda nuppu "tõeväärtus", vali "string"
1.3 "Sisesta string" lahtris lisa järgmine user-agent string (lehitseja versioon, mille lehitseja saadab seatud leheküljele, antud juhul postimees.ee) —

Mozilla/5.0 (X11; Linux armv7l; rv:47.0) Gecko/47.0 Firefox 47.0

Kui telefonis on Android 2.2, või kui telefonis ka on Android 2.3, aga protsessoriarhitektuur ARMv6, siis nende jaoks on uusim Firefox hoopis versioon 31.3.0esr. Siis peaks kasutajastring olema selline:

Mozilla/5.0 (X11; Linux armv6; rv:31.0) Gecko/31.0 Firefox 31.0

1.4 Olles sobiva kasutajastringi sisestanud, vajuta nupule "Loo".
Antud string kehtib ainult Firefox 47.0 kohta. Kui sinu Firefoxi versioon on erinev, peaksid lisama selle, mis sul on.

Kogu see tegevus seab postimees.ee domeenile töölaua-põhise lehitsejastringi (i.k. user-agent string) nii, et Postimehe koduleht saadab Firefoxi-mobiililehitsejale töölaua-versiooni.

Ülal väljatoodud kasutajastringis tähendab näiteks X11 Unix-põhiste opsüsteemide graafilist keskkonda, Linux tähistab opsüsteemi nime (sh samanimelist kernelit, mis on Androidis sees), armv7l mobiiliseadme keskprotsessori tüüpi, rv: ja Gecko tähistavad Gecko veebimootori (mida kasutavad Firefox, IceCat jt lehitsejad) versiooni, selle järel lehitseja enda nimi (siin vastavalt Firefox) ja versioon.
3. Aga see pole veel kõik, sest Postimehe töölaua-versioon mobiilis ju päris korralikult ei näita, sest pisikesel ekraanil on töölauaversioon liiga lai, tekst liiga väike, ning tuleks liiga palju suurendada.

Et vähemalt enda jaoks probleemi kiiresti lahendada, tegin järgmist:

Installisin Firefoxile laienduse nimega Stylish. Sellega on võimalik muuta lehitsejas näidatavate lehekülgede välimust läbi mobiiliseadmesse tõmmatud kasutajastiilide (i.k. userstyles).
Stylish laiendus töötab nii, et lehitseja tõmbab mõne lehekülje kasutaja seadmesse ja seejärel rakendab Stylish leheküljele seatud kasutajastiilis oleva küljenduse. Lehekülje originaalvälimus jääb lähtekohas ikka samaks, st. kogu see välimuse muutmise protsess toimub ainult kasutaja seadmes, kui kasutaja on mõnele lehekülje mugavama kasutamise tarvis tõmmanud kasutajastiili.
Edasi veetsin selle aasta kevadel mitu ööd ja päeva uurides töölaua-Firefoxi arendajatööriistade abil Postimehe lähtekoodi ja kirjutasin oma stiililehe, et nö tagasi saada mobiilide jaoks mõeldud klassikaline välimus.

Et kõik teisedki inimesed saaksid seda stiililehte kasutada, panin kasutajastiili üles GitHubi:

https://github.com/juneyourtech/GM_PM/raw/master/PM_mobile_classic.css

1. Kopeerida ülalolev aadress.
2. Firefoxis minna läbi Lisade lehekülje Stylish alamlehele: Menüü [> Veel >] Lisad > Stylish;
3. Vajuta "Halda stiile" nupule;
4. Vajuta nupule "Install from URLs", aseta tekstiväljale ülalolev kopeeritud aadress. Vajuta Sobib/OK, kirjuta lisaks stiili nimi.
5. Postimehe töölaua-versioon peaks sestpeale olema nähtav mobiilidele sobilikul kujul.
6. Edaspidi tuleks eelistada Postimehe www-aadressi kujul www.postimees.ee

Ei garanteeri, et see kasutajastiil töötab kõigi peamiste Postimehe alamlehtedega (eriti Ilmajaam).

Reklaame see kasutajastiil otseselt ei blokeeri, kuid üldiselt olen lähtunud sellest, et Firefoxile Androidil on peale installitud skripte blokeeriv NoScript Anywhere laiendus, milles on antud postituse teemat silmas pidades lubatud peamiselt postimees.ee ja pmo.ee domeenid.
Tavalisest reklaamiblokeerijast, nagu Adblock Plus vms., on NoScript mitu korda efektiivsem ja vähem ressursinõudlik; leheküljed laevad kiiremini, ning selles oleva valge nimekirja abil on lubatud ainult need domeenid/võrgulehed, mida vaja.

Inimestele läheb korda telefoni või tahvelarvuti akutarve. Skriptide blokeerimine lehitsejas säästab nii aega, akut, ning mobiil-Interneti kasutajatel ka raha.
Läbides kõik need sammud ongi võimalik Android 2.3 opsüsteemis saada endale võimalus normaalselt lugeda Postimehe uudiseid ja hinnata artiklite kommentaare.


Veidi ajaloost:

Valmistehtud stiililehe esialgne tulemus oli rahuldav, kuid alguses ei olnud mul veel õiget lahendust, mille abil olnuks võimalik PMO töölauaversiooni probleemivabalt kätte saada, isegi kui teatud olukordades paistis disain töötavat.

Hiliskevadel või suvel tõmbasin eksperimenteerimise käigus peale Firefoxil põhineva GNU IceCat lehitseja, millel pooljuhuslikult avastasin kasutajastringi muutmise võimaluse, ning ka selle, et erinevat kasutajastringi on võimalik seadistada erinevatele saitidele.

Sügisel avastasin lõpuks, et ka Firefox toetab sama funktsionaalsust; lihtsalt on see about:config lehel iseenesest mitteeksisteeriv ja user-agent string tuleb ise lisada.

Tuesday, November 1, 2016

CSS3: Match parameter contents with the :not pseudoclass

It's possible to match parameter contents in the :not (negation) pseudoclass used in Cascading Style Sheets Level 3 —

A:not([href*="subdomain.domain.tld"]) {color:blue;}

All links are colored blue except those targeting anything that contains subdomain.domain.tld .

The asterisk * before the equals sign = means, that the match is any parameter value inside double quotes (quotes may be optional or pursuant to syntax) — in this case, links (A) that contain subdomain.domain.tld — to which a particular CSS rule is not applied using :not([]). Here, link contents can be a variation of
https://subdomain.domain.tld/directory/folder/file.html

More complex use of the :not pseudoclass:

A[TARGET="_blank"]:not([href*="subdomain.domain.tld"]) SPAN {color:yellow}

All SPAN elements inside links (A) with TARGET="_blank" (these typically open new windows) are colored yellow; except those, where link address contents match subdomain.domain.tld

Approximation in HTML:
<A HREF="https://domain.tld" TARGET="_blank"><SPAN>Text in this link's SPAN element is colored yellow.</SPAN></A>

<A HREF="https://subdomain.domain.tld/folder/file.html" TARGET="_blank"><SPAN>
Text in this link's SPAN element is not colored yellow, because it matches subdomain.domain.tld .</SPAN></A>
The W3C CSS3 spec itself is rather fuzzy about all this, but after some experimenting, I got a satisfactory result with a userstyle.

And if it works in a modern version of Firefox, it should work in other browsers, too.

Additional notes

If you want to match by the existence of a parameter inside an element, such as ENABLED inside <BUTTON>, or use a simple selector, such as a .classSelector or #idSelector — then you have to do without square brackets []:
A:not(TITLE) {}
   /* all links that do not contain TITLE
      (without tooltips on link hover) */

BUTTON:not(DISABLED) {}
   /* all buttons that are enabled */

DIV:not(.frontpage) {}
   /* all DIV elements not with class="frontpage" */

DIV:not(#articleContents) {}
   /* all DIV elements not with id="articleContents" */
...and so on.

Other selector matching rules apply, too.

Errata

Strangely enough, I found it impossible to insert or nest a negation pseudoclass into a series of combining selectors (with Firefox 39.0.3):

DIV A:not([href*="subdomain.domain"]) SPAN {parameter:value;}

— where a multi-selector involving SPAN elements inside links without subdomain.domain and inside DIV elements would not work.

So, in a ruleset, the negation pseudoclass must be listed first, and can include child selectors, but cannot be a child selector itself.

Rationale

As it was, this post was borne out of a need in a userstyle (made to improve the functionality of one website) to give all links that open in new windows using TARGET="_blank" a certain visible background, which was a yellow gradient, so that the reader could decide how they should open those links.

The exception to that rule was to avoid setting that background to weather content, as it was based on elements for which the website applied its own background images. Incidentally, these backgrounds were dynamically applied to child elements inside links with TARGET="_blank", and setting one's custom background replaced the background images, and weather information was thus lost.

As the links resolved to the website's weather subsite, then excluding those required matching the weather-themed subdomain, as in weather.website.tld and the links' SPAN, B, and other child elements that already contained backgrounds.

Of course, I could have specifically targeted several large and content-heavy parent DIV elements that did not contain weather content, but this would certainly have required involving way more than one such DIV element.

I could have also tried using a negation pseudoclass with a simple selector, as in:

DIV:not(.thisclass) A[TARGET="_blank"] {background:gradient(to left, yellow 0px...)}

... and maybe this would have worked, too. — But then I would have risked missing several non-weather links that did open in new windows, and as such, these would in turn have remained potentially invisible.

Therefore I found it more prudent to use link-based selectors.

Article Errata:
Corrected terminology of :not being a pseudoclass instead of a pseudoelement.

Finding the classic Netscape/Mozilla hand cursor

If there is anyone who remembers using Netscape (oh, the good times), they will also remeber the business-like hand cursor that appeared on hovering over links. This cursor is a classic.

Now, originally, the cursor was available at this address:
http://lxr.mozilla.org/mozilla/source/widget/src/build/res/select.cur?raw=1

Alas, that resource is not available anymore.

And whilst
https://dxr.mozilla.org/mozilla1.8/source/widget/src/build/res/select.cur
also exists, I'd found no way to download it.

So, as I was googling (yes, I still..sometimes do that) this classic hand cursor with the
/mozilla/source/widget/src/build/res/select.cur
search string —

I found this awesome resource on GitHub:
https://github.com/krad-radio/mozilla-krad/blob/master/widget/src/build/res/select.cur
Apparently and for reasons unknown, a software developer took the classic Mozilla source and wanted to improve it.
The download link was there all right, so I got my favourite cursor.

License information

As the original Mozilla Application Suite was licensed under the Mozilla MPL/NPL/LGPL tri-license, then this should apply to the subject image shown at the top of this post.