Wednesday, November 2, 2011

english grammar1

"Hi everyone, I feel good"

"I feel good today"

"I feel [now] that you should not have said that to her." or "I felt [at that time] that you should not have said that to her."

"I feel hurt when you say that" -- now or "I felt hurt when you said that"-- in the past

"Yes, Amanda is right [now]" or "Yes, Amanda was right [then]"

"He died for his country. He was a good soldier." -- He is dead, therefore he 'was'.

"I saw him run away" -- 'run' is an infinitive: I saw him run, I will see him run, I see him run, I have seen him run, etc.

"take three capsules daily after a meal". Take just 3 capsules after your choice of one meal in a day


One good grammar book is Michael Swan's Practical English Usage.

Tuesday, November 1, 2011

emulate vs simulate

ever since= since then

Emulation Vs. Simulation

1.

Computer emulation and simulation are different forms of copying something. Emulation copies another computer or machine, so that the software from one machine can run on an otherwise incompatible machine. Simulation copies a system or a situation. Some aspects of a simulation can be controlled by the user, while other parts are designed to act as they would if the situation were real instead of simulated.

1.
Emulation
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Emulation is making one computer act like a different computer. One of the most popular applications of emulation technology is using an emulator program to run gaming software from outdated computers, like the Commodore 64, on new PCs. Gaming emulators can also make PCs run games from older consoles like Nintendo or Sega Genesis. Another practical application of emulation software is to emulate the OS, or operating system, of a different computer. An emulator can be used this way to make Mac software run on a PC or vice-versa.
Legality
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Emulators that allow computers to run software from other types of computers, or even gaming consoles are perfectly legal. Many emulators are freeware and open source, meaning anyone can download them and anyone has access to the actual programming code. But many of the games that can be played through emulators are illegal. The read only memory games, or ROMs, are usually copies of copyrighted software. Those are illegal to distribute or download.
Other Devices
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Emulators are also common for smart phones. smart phone keypad image by Jon Le-Bon from Fotolia.com

Emulators aren't only made for computers. Emulators are available for iPods, iPhones, Blackberries, Google's Android and other "smart" devices. Most of these emulators are designed primarily for game play. Some of them are fully and legally licensed and some are more homemade versions available for free.
Simulation
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Simulation is also a from of mimicry, but it is different than emulation. A simulation is a computer recreation of a particular scenario. Simulations are designed to act like an authentic system or situation. Simulations are popular in the gaming world, one of the first being Microsoft's Flight Simulator. Many other games allow users to recreate theme parks, restaurants or historical battles. The Sims series is just a simulation of everyday life.
Other Uses
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Pilots may log many hours in simulator cockpits before they actually fly a plane. flight deck image by Andrew Breeden from Fotolia.com

Simulations are valuable scientific tools. They are common in physics, biology, chemistry and engineering. They can allow scientists to study virtual scenarios that may be impossible to actually create. Simulations are also used in economics, mathematics, sociology and other fields. Simulators are also an integral part of flight training programs for pilots. Microsoft's Flight Simulator is just a game, but real flight simulators create a realistic, but perfectly safe experience for pilots in training.

2)
Wow! I hadn't thought about how similar these four words are. The common theme is they all mean "copy" in some way. But the context and usage can be different.

emulate

This is usually used with someone as an object.

For instance, You should emulate your grandmother. She is a wonderful person.

to use someone as a model because you think that person is excellent in some way; to try to achieve desired qualities by acting like someone who has those qualities

simulate

this has the idea of copying something so that the copy pretends to be the original thing

It isn't the original thing and isn't trying to be the original thing; the aim is to appear to be the original thing.

For instance, The suitcase is made of simulated leather. (simulated leather = some other material that is made to look a lot like leather)

mimic

Webster's 21st Century Dictionary says:

1. a person who imitate mannerisms of others (noun)

2. imitate as a mimic (verb)

When Mr. Jones shaves in the morning, his young son likes to mimic him. (The young boy makes shaving motions the way his father does.)

imitate

To me, this seems to be the most general of the four words. I think it can be used in the "emulate" sense, in the "simulate" sense, and in the "mimic" sense.

Webster's 21st Century Dictionary says:

have the same characteristics as

(But there's also the idea of copying something else.)

3)
The first question regarding the difference between simulator and emulator I encountered in my undergraduate class of computer organization and architecture. The lecturer gave the difference in the aspect of completeness. But, ever since I had been wondering about the difference. Therefore, today I decide to round up the difference based on my own life experience of using simulator and emulator.

Simulation is the imitation of another environment. For example, a flight simulator imitates the environment of flying an airplane in a little room. The true environment of flying is experienced in another environment that lacks some aspects like the possibility to die from a plane crash. So, simulation usually involves an environment and a person. Well, if not a person, another object. For example, a savanna simulator may include a lion to see how the lion will react to a certain condition. About simulation, you usually says: "I want to know how this person/animal/plant/object reacts in a particular environment".

Emulation is the imitation of an object as another object. For example, a PlayStation emulator makes PlayStation game CDs recognize a PC as the machine where they are intended to run. Another example, a man puts on fake breasts, wear woman clothing and soften his voice to emulate a woman. So, basically an emulation has a purpose to make its environment recognize an object as another object. This is why emulator needs to be complete. If, for example, the man emulating a woman fails to emulate a woman completely like urinating while standing, he will be found out not to be a woman. About emulator, you usually says: "I want to make this stuff be recognized as that stuff so that another thing that I have in mind will continue to interact with the emulated stuff in the way it interacts with the real stuff".