43 votes

Why not put servers in a refrigerator?

A refrigerator is basically a heat pump designed to achieve a temperature close to 0 °C. There are a couple of problems here: Most refrigerators are way too weak to effectively tackle the heat output ...
  • 431
20 votes
Accepted

Why is it more reliable to use the land/pit transition in a CD-ROM?

To elaborate on ratchet freak's answer; CD-ROMs work by sensing the intensity of the light reflected from the CD as it is spinning. More light being reflected stands for a 1 and less light being ...
18 votes
Accepted

Why not put servers in a refrigerator?

We do. It's just an up-sized (i.e. more powerful) version of a refrigerator known as an air conditioning unit. Essentially all server rooms and most spaces where PCs are located (speaking for the U.S.,...
  • 296
12 votes

Why not put servers in a refrigerator?

refrigerator boxes tend to generate condensate There are specifications for acceptable relative humidity (RH) for servers. Air conditioning in server rooms will maintain RH within the allowed limits ...
11 votes

Why is it more reliable to use the land/pit transition in a CD-ROM?

Because of optical interference. When the laser is fully in a pit or fully on land then it gets reflected cleanly and will be picked up by the sensor. However, on the transition, half the laser is ...
11 votes
Accepted

How do Thumb instructions compare to ARM instructions for performance?

In General THUMB instructions aren't to my knowledge intrinsically slower than ARM instructions, but rather are more limited in capability. If your code only needs the functionality of THUMB ...
  • 296
11 votes

Why not put servers in a refrigerator?

Here's a webpage from a random guy who put a light bulb in his refrigerator to see what would happen, and took careful data to monitor it. Results: The next experiment was to put a 60-watt ...
5 votes

How can I vaporize metals?

The easiest way to vaporize a metal is to create a filament of the metal. Heat the filament in the vacuum to its sublimation (vaporization) temperature. Alternatively, when the metal cannot be shaped ...
5 votes
Accepted

Screw type associated with COM port/DB-9

4 - 40 UNC ASME/ANSI (US customary units rather than Imperial) Thread Specifications The final two digits are the number of turns per inch, so the pitch is 0.025" (US: 25 mils, UK: 25 thou).
5 votes

Why not put servers in a refrigerator?

They've been doing that with computers for 30+ years. Back when computers were the size of refrigerators. They use to get a regular air conditioner. Build a platform for the computer to stand on. ...
  • 51
4 votes

Why not put servers in a refrigerator?

The price-to-effect ratio for heat pumps is just not there for any large scale applications. Especially since air or watercooling is far less complex, and therefore a lot, lot cheaper. Dust is ...
  • 140
3 votes

Relation between residual stress and von mises stress calculated by FEA in comercial software

The Von Mises Stress and the residual stress are not the same thing. To get the residual stress, do another time step where all the applied loads are zero. If there is material nonlinearity (...
  • 12.5k
3 votes

Use two passive CPU coolers on one single CPU?

Well, I would think that two smaller ones rigged up in an "amateurish" fashion (apologies, but that's we both are, right) are going to be worse than just one (sufficiently large) properly mounted ...
  • 251
3 votes

Byte organized and Word organized memory using memory modules

If you notice, you need 20 bits to access the 1Mb byte modules. But your processor is word aligned. So 2 1Mb byte modules form a 2Mb word module. The key to understanding how it works is the ...
3 votes

Computer engineers -- do computers use varying amounts of power?

Yes, a computer uses varying amount of power. Yes a 3D printer uses a varying amount of power. In fact all electrical devices do vary based on load. Both motors and processors use more energy when ...
  • 3,435
3 votes
Accepted

Can you perceive similar kind of "humanizing" of technology in other fields of engineering than computer science?

An important factor is that computing inherently has a numbers of layers of abstraction and function between the end user and the actual functionality. To some extent this is a from of automation in ...
  • 15.1k
3 votes

Explanation of network interdiction in layman terms

The first paragraph from your second reference seems pretty clear. The first sentence states that Network interdiction is the monitoring or halting of an adversary’s activity on a network. ...
3 votes

What is the significance of a processors bit capacity?

There are several components in a microprocessor that may all have their individual size: data bus, address bus, registers, and ALU (arithmetic logic unit). Modern CPUs also have caches, memory ...
  • 679
3 votes

How to introduce the CONSTITUTIVE equation into structure mechanics

The balance of linear momentum is $$ \nabla \cdot \boldsymbol{\sigma} + \rho \mathbf{b} = \rho \mathbf{a} $$ where $\boldsymbol{\sigma}$ is the Cauchy stress, $\rho$ is the mass density, $\mathbf{b}$...
3 votes
Accepted

Are pixels not squares and more like rectangles?

Looks like a square to me - are you sure you selected the pixel checkmark, and also unchecked the "Maintain aspect ratio" box before typing in your second '500'?
3 votes
Accepted

Microscope Camera Windows NT

(Without knowing the model) Short answer is no. In general older cameras (and even some newer ones) tended to use very customised communication protocols and drivers. Also the transition from Windows ...
  • 22.9k
2 votes

What is the significance of a processors bit capacity?

A 64 bit processor has a datapath and memory address width of 64 bit. The integer size is also 64 bits. In addition the registers, address bus and data bus is 64 bits wide. Likewise in a 32 bit ...
2 votes

Computer engineering: Physical time clock timing

Most computers / computing devices will have a real time clock (RTC) built in. This is normally included in the processor or motherboard chip set rather than as a separate part. It will be designed ...
  • 766
2 votes

What can I use to calculate distance?

There are a couple of solutions available. You will have to decide a budget and the required accuracy to settle for one. 1) Laser distance sensor - These will give you pretty accurate measurements ...
2 votes
Accepted

BTech or BSc engineering

I think Bachelor of Technology (B-Tech) is mostly a designation used by Indian Institute of Technology (IIT) and National Institute of Technology (NIT). This write up describes Bachelor of ...
2 votes
Accepted

Why laptop keyboard has so many bus lines?

The keyboard contains many switches (100 in my keyboard at this moment) and the simplest solution for a keyboard assembly that contains no decoding circuitry would be for each switch to have its own ...
2 votes
Accepted

What is the mechanism of transition in applications of finite state automata?

A synchronous system with a clock is not necessary. The transition between states can be triggered asynchronously by inputs to the system (e.g. someone pushes a button to operate an automatic door). ...
  • 12.5k
2 votes

How to find the smallest change in voltage

I order to solve this problem there one needs to understand the following ADC range which is the maximum and minimum ADC input. For this problem the range is 3.2V, -3.2V. ADC resolution which is the ...
2 votes
Accepted

How exactly do noise canceling headphones work?

Briefly they take the waveform of the ambient noise then produce the inverse waveform which is then generated. The two waveforms effectively cancel out leaving a much quieter ambient sound level. The ...
  • 14.2k
2 votes
Accepted

How is the most basic display driven?

Pretty much every display is multiplexed. Typically each column is turned on (pulled to positive supply, for example) in turn and the rows for the pixels to be turned on in that column are switched to ...
  • 8,824

Only top scored, non community-wiki answers of a minimum length are eligible