sexta-feira, 30 de novembro de 2012

Tarifa bi-horária vale a pena? (para Engenheiros e afins)

(1) x*0.0833+y*0.1551 < (0.1393*0.95)

(2) y > 0.15

(x+y = 1)  x,y são percentagens complementares




x ~ % do consumo vazio
y ~ % do consumo não vazio
(por definição x+y = 1 ~ 100%)
0.0833 = tarifa do consumo vazio
0.1551 = tarifa do consumo não vazio
0.1393 = tarifa do consumo (tarifa simples do mercado regulado)

(1) x*0.0833+y*0.1551 < 0.1393
Neste caso testamos se o pago pelo consumo vazio somado com o pago no consumo não vazio é inferior ao mesmo consumo com a tarifa simples.[0.1393 = 0.1393*1 = 0.1393*(x+y)]

Usando o valor (0.1393*0.95), ie, 95% do valor da tarifa simples (regulada pelo mercado) estou a ter em conta o desconte de 5% oferecido pela Galp para tarifas simples no plano (5%+5%) simples electricidade + gás. No caso de aderirmos a electricidade na tarifa bi-horária o desconto apenas é aplicado no gás (0%+5%), daí este estudo.

(2) y > 0.15
Para efeitos de adaptação à realidade pressuponho que o consumo no não vazio equivale a pelo menos 15% do consumo total (y>0.15) já que há sempre um frigorífico ou congelador ou seja o que for ligado.

Este resultado (ver gráfico no link) traduz também a noção que temos de que devemos "transferir" os nossos consumos para as horas de vazio (aumentar x, reduzindo por consequência o y) e consumir o mínimo nas horas não vazio(reduz o consumo mais caro).

Usei percentagens por simplicidade mas poderia usar os consumos efectuados directamente.

Conclusões:
Resolvendo mat(h)ematicamente  x > 4553/14360 , ie, o consumo vazio tem que ser superior a 31,7% para valer a pena aderindo ao Galp On Simples. 
Por consequência da inequação (2), x < 17/20 ,  ie, na prática o consumo vazio nunca será superior a 85% - mas se for tanto melhor xD )

Notas: Caso válido para uma potência contratada de 6,9kVA BTN (menor que 20,1 kVA) e para o 1º e 2º escalões do gás.

quinta-feira, 23 de fevereiro de 2012

Google Docs SECURITY FLAW!

I has been for a while now since I use Google docs and now I have stumbled upon a MAJOR security flaw!
While using Google Docs and Gmail  at The same time I notice something interesting. I had uploaded a picture to Google Docs (using gDocs as a file depot) but later I deleted it. Next day I opened Gmail and I have a miniApp for GoogleDocs (next to chat left bottom corner) where it shows my latest docs. Well I saw my deleted pic there and went... AWWW. Wait! This could easily be a cache error and the link isn't valid anymore.. let's click it! ... CLICK! .. AWWWW and voilá.
The picture opened! Then I searched (the miniApp has a search feat) for other pics I deleted (searched for "jpg" term) and ALL my deleted pictures where there! WTF!

Be careful what you upload to Docs... it might be permanent!

segunda-feira, 24 de outubro de 2011

iPhone 3GS (new boot) Jailbreak + Unlock process



Hi,

Here I'll be describing my 'adventure' to successfully unlock iPhone 3GS (new bootloader) without SHSH blobs.


If you check my previous Blog entry you'll see how hard it was for me to downgrade. Well, unlocking wasn't easier!

The key points to unlock this phone are:


  • Upgrade to iPad baseband (if you have an incompatible baseband)
  • Restore to stock iOS 4.1, then to custom iOS 4.1
  • If need install iPad baseband again!


Upgrading to iPad baseband was pretty easy at first but there are a few thing you should have into consideration BEFORE doing this:

  1. Upgrading doesn't allow you to restore your previous baseband (so far there is no such tool but there might be in the future)
  2. Using iPad baseband might make your GPS useless. (not sure if this was ever fixed or if it will be)
  3. Installing a stock IPSW after this might render you iPad baseband useless, if so reinstall iPad baseband.
Ugrading to iPad baseband can be done using either redsn0w or sn0wbreeze. 

What I did was what is think is the safest:

  1. Restore to stock iOS 4.1 (not 4.3.3) - see my previous post
  2. Saved my SHSH blobs using TinyUmbrella
  3. Enter normal DFU mode and restore to costume iOS 4.1 (not 4.3.3)
  4. After all is done upgrade to iPad baseband (using latest Redsn0w)
  5. Use ultrasn0w (current version 1.2.4) to unlock you device, from cydia.
Comment if you have any questions! ;)

domingo, 23 de outubro de 2011

iPod / iPhone Downgrade WITHOUT NO SHSH blobs! (any OS version up tp 4.3.5)



The technique might seem simple to most but I assure you this is easy to mess up!

You'll need:
iREB
fixrecovery421
TinyUmbrella
iTunes

(you may use others tools at your own risk)

[useful link: Download Restore Files (Mirror)]

Steps:

1. Enter DFU
2. Use iREB (enters Back screen Pwnd DFU)
3. Use fixrecovery421
4. Run TinyUmbrella and run Tss Server.
5. Restore with any ipsw using iTunes.

HOW-TOs (each step corresponds to the ones before)

1.
a) search the web
b) use a trustworthy resource:
c) use my technique(s):  (PB: power button, HB home button)

  • [DO IT SLOWLY NO RUSH] With iDevice off and plugged in (absolutely off!), press PB until it turns on (1-3 secs) and hold, then also press and hold HB until it goes from apple logo to black screen (usually ~10 secs), then release the PB (you should now only hold HB) until it enters DFU (usually 15-30 secs, screen can remain black or turn white, windows indicates a new hardware connected/just makes a sound if it is already installed)
  • With iDevice on any DFU or Recovery Mode press and hold both HB and PB and when it turns off  release at once both and press and hold only PB and proceed as above.
2. Open iREB choose you iDevice and follow on screen instructions (includes entering DFU mode).

3.Must have zlib1.dll to run fixrecovery421. Run it and you should see some code running on your computer and after (and during) some running on your iDevice.

4. If in Win 7 and/or x64 you can't see TinyUmbrella and only see a black bar onscreen then switch to widows basic theme or to windows 7 Aero wich ever you and NOT in at the moment (it's switching the AERO that triggers it). Then wait and it will show. Then click Start Tss.
NOTE: before starting the server no processes must be using port 80 or else Tss Server simply WON'T run.

5.I've faced many errors here but i've found a weird error 2005 that wasn't documented anywhere on the web in this situation which is: iDevice in Black DFU mode (PWND or not) and couln't get it in any other mode, then to get it to what should be white DFU mode (not sure if it is but screen is white) I did:
  • Run fixrecovery421 and PAY ATTENTION to the window that is running.
  • When it says "waiting 10 secs for device to pop up" wait until your device's screen is white and CLOSE the window (alt+F4 or Ctrl+C).
  • Proceed to restoring.
NOTE: couldn't restore 4.3.3 for some reason but did it for 4.1. In a different device 4.3.3 was sucessful both custom and stock iOS 4.3.3



Good luck!


Wan't Jailbreak?
Consult http://blog.iphone-dev.org/ aka DEV-TEAM

try:
Redsn0w
Sn0wnbreeze
JailbreakMe 3.0


domingo, 5 de setembro de 2010

quarta-feira, 3 de junho de 2009

Geek Heaven!

PROCESSOR Intel® Core™ 2 Extreme QX9300 (2.53GHz,1066MHz FSB,12MB L2 Cache)
LCD 17-inch Wide UXGA 1920 x 1200 - Beyond HD (1200p) Display
MEMORY 8192MB 1333MHz Dual Channel DDR3 SDRAM [2x4096]
HARD DRIVE 1TB (7200 RPM) Free Fall Sensor Raid 0 "Stripe" Dual HDD - (2x500GB)
GRAPHICS CARD SLI™ Dual 1GB GDDR3 NVIDIA GeForce GTX 280M
OPTICAL DRIVE Blu-Ray ROM combo (Blu-ray read only, DVD, CD read & write) Optical Drive
PRIMARY BATTERY 9-cell 85Whr Lithium Ion battery

e é um PORTÁTIL!!!

AlienWare M17x








É excelente não é?

Só custa €5161....

Pois ah e esqueci-me de dizer que só se vende nos Estados Unidos!

Mais portes (+/-€100) e 20%IVA... (20% = 1/5; 5000/5 =€1000) sim são mais de 1000€ de IVA

Era bom, não seria?

quinta-feira, 28 de maio de 2009

Nimbuzz is the best!

Three IMs for the high companies of web,
   Seven for the smaller ones in their small corners,
Nine for mortal companies doomed to die,
   One for the Great Lord on his Throne
In the Software of Nimbuzz where the Talks lie.
   One IM to rule them all, One IM to find them,
   One IM to bring them all and the Greatness Bind them
In the Software of Nimbuzz where the Talks lie.


My Own Lord of the Rings fan fiction! (?)
And of course Homage to Nimbuzz!

If You like Instant Messaging and don't want to Have 300 applications to do the same get Nimbuzz (Nimbuzz.com) available in PC and Mobiles Phones (incl. iPod Touch)
For more info visit twitter.com/nimbuzz or blog.nimbuzz.com