Injection Definition and 93 Threads

If there exists an injection $f: X\rightarrow Y$ then there `obviously' exists a surjection $g:Y\rightarrow X$, got by noting that the restriction of $f$ to $f(X)$ is a bijection between $X$ and $f(X)$ and so invertible, and then mapping everything else in $Y$ to some fixed element in $X$...

Hello, I'm currently doing research into the various effects of exhaust gas recirculation for my dissertation at university, the engine being tested on is a naturally aspirated 4 stroke diesel Ford straight 4 (probably out of a transit or something of the sort). Last week I recorded cylinder...

Homework Statement How can I prove this? If g°f is a bijective function, then g is surjective and f is injective. Homework Equations The Attempt at a Solution

Hi all, My problem is a question from my coursework. The question is; We are to inject propane gas into the diesel engine of the Vauxhall Omega on a dyno run. Calculate how much gas is required to give the engine 60nm more torque? obviously i can appreciate some people may not want to...

Only assuming that the worst will happen and that will include the complete breaches through the bottom of the sealed containment of all four reactors, wouldn't it be possible, first, and then prudent, second, to be ready to cool these molten masses with liquid nitrogen being injected...

i recently saw the CRDi system ,its working and its performance test.Now there is a particular mechanical pressure control valve being used in the rail to prevent excess pressure,this valve works each time pressure goes beyond the limit and brings it down,but it is said that this happens only...

It's reported that sodium thiopental, the first of the three-drug cocktail in lethal injections, has been in short supply across the US and the state of Oklahoma responded a few days ago by using a veterinarian drug instead. Some other states have suspended executions. Strangely, none of the...

HELP on a spacecraft mission to saturn for the injection velocity i beg you please Homework Statement on intial approach to Saturn, the spacecraft mass is 3500 kg. To enter orbit around Saturn , the vehicle has a 400N thrust primary propulsion engine, with a specific impulse of 310 sec...

how do you prove injection and surjection of the function of 2 variables. for example f:RxR->R

Bear with me if you notice any botched ideas in my writing, I'm working on it. Initially I was wondering about direct injection of ATP. But I ran into a roadblock... First - Is it possible to isolate ATP from a source and make a high concentration ATP solution or even pure ATP? (extraction...

how to prove it please?

Hi all, Here are some questions for injection molding: 1. How to calculate total mold volume? 2. How to calculate how many parts can be produced? 2. How to calculate clamping force? Further details of the question is in the attachment. Thx for any answers might given. ^^

Homework Statement That's what I'm supposed to prove. Homework Equations A function f is an injection if f(x1)=f(x2) ---> x1=x2 The Attempt at a Solution I'm just having trouble constructing a formal proof. I mean, it's obvious that f(g(x1))=f(g(x2)) then either g(x1)=g(x2)...

Hallo all, I need a very conceptual and clear cut definition on sql attacks...there are so many forms of definition and material available on internet that I am just so confused...what the most reliable and authentic source to grasp this info. Thanks

Injecting error in the transport stream using the pc based modulator whether will affect the BER of the stream. Because while my testing the BER is not even varying but Transport stream error packet count will increase. Any one could you please the above beghaviour.

Instead of drag racers injecting nitrous oxide and extra fuel with it . Why don’t they just inject liquid oxygen with more fuel . for more power , Any input will be much appreciated.

Homework Statement Are the given functions injective? Surjective? a) seq: N -> Lists[N] b) f: Lists[A] -> P(A), f(x)=(<x1,x2,...,xn>)={x1,x2,...,xn} Homework Equations The Attempt at a Solution a) Ok so the domain contains a sequence of natural numbers. and the range contains a list? What...

Let A,B, and C be nonempty sets and lef f map A to B and g map B to C. If g of f maps A to C is an injection, then f is an injection. Not sure how to do this proof

We are a group of students at the Florida Institute of Technology looking for information on fuel injection systems/manufacturing advice/design advice/any kind of advice that would be imperative to the design of a fuel injection system for a liquid fuel rocket engine. We have funding for a large...

Hi, I would like to say this is a great forum I found. This is my very first post yay =) I need help on these certain questions. 5. (10%) Given A = {1, 2, 3} and B = {a, b, c} (a) list in two-line notation all one-to-one functions from A to B; (b) list in two-line notation all onto functions...

Hello, I am trying to simulate reactive power injection with a single phase inverter. The constant dc bus voltage on the input side is maintained much higher than 169.71V (considering 120V rms ac output). I have generated the current reference for the control (a PI based system) but it doesn't...

Homework Statement Heres the question asked: Consider the above FIA apparatus. Calculate the Dmax (as seen by the detector) for the apparatus assuming that a 300uL injection volume results in no dilution (dispersion) of the injected sample by the sample stream line in this system...

I'm having trouble understanding just what is the difference between the three types of maps: injective, surjective, and bijective maps. I understand it has something to do with the values, for example if we have T(x): X -> Y, that the values in X are all in Y or that some of them are in Y...

Matlab 2-D Simulation for TLI (Trans Lunar Injection) "Basic Orbital Mechanics" Hi Everyone, I have been assigned a project in which I am to program in MATLAB the solution to the 3-body problem, but in 2-D with a couple assumptions. 1) Earth and Moon are stationary. 2) Mass of spaceship...

Hello, I need some help with the general very basic cost analysis of an injection molding machine and a mold for a particular part (Plastic Gear). For example, a Gear made out of Nylon plastic resin. The gear dimensions are roughly 2 cm diameter (20 teeth). Something like the black one...

Please help, book gives no examples relatively close to this. A rocket is fired in deep space, where gravity is negligible. If the rocket has an initial mass of 6000 kg and ejects gas at a relative velocity of magnitude 2000 m/s , how much gas must it eject in the first second to have...

f(x) is a bijection if and only if f(x) is both a surjection and a bijection. Now a surjection is when every element of B has at least one mapping, and an injection is when all of the elements have a unique mapping from A, and therefore a bijection is a one-to-one mapping. Let's say that...

http://www.wsmv.com/news/16844880/detail.html It surprised me to read about this. I wonder if Nashville is the only city where this is done.

What is direct injection technique which is being used in automobiles nowadays.

Real or what? http://www.belfasttelegraph.co.uk/health/article3603996.ece?a=3603996 They claim 90 per cent respond to the treatment, usually within minutes, and have released videos of patients to prove it. In one, a nurse sits down with an 82-year-old patient, Marvin Millar, who...

recently i got a tetanus-prevention injection.. and i noticed that the nurse after piercing the needle, plugged the plunger back and took some blood inside the syringe [very little].. like 1/10th the solution in it and then pushed the plunger back. My question is.. why did she do that? My first...

Homework Statement Given a field F, I'm trying to find an injection from the set of formal Laurence series F((x)) \sum_{n\geq N}^{+\infty}a_nx^n, \ \ \ \ \ N\in\mathbb{Z} to the ring of fractions of formal power series \mathbb{Q}(F[[x]])...

Homework Statement Show that there does not exist an order-preserving injection from the ordinal \omega_1 to the reals (given the usual order). The Attempt at a Solution Suppose such an injection exists. Then something bad happens. Maybe the fact that w1 is well-ordered?

Let A,B,C be infinite sets. Suppose there is no injection from A to B and no injection from B to C. Prove there is no injection from A to C (without using cardinality and Schroeder-Bernstein). My current solution: Let f:A-> C. Assume f= s.r (. means composition), where r:A-> B and s:B->...

MAGIC engine http://www.mitsubishi.com/mpac/e/monitor/back/0608/green.html The exciting thing about the MAGIC engine is that it introduces competition to the market, the first time since the demise of the steam and electric motor cars. Just watch oil prices drop like a brick striving...

Ok so I know with the injection of potassium chloride, the potassium in the extracellular fluid works to inhibit any repolarization, by increasing the amount of K in the extracellular fluid (hence not allowing EPSPs to reach threshold and trigger Na channels for an action potential), however...

I was just looking at the definitions of these words, and it reminded me of some things from linear algebra. I was just wondering: Is a bijection the same as an isomorphism?

If someday complete direct injection spark ignition with gasoline engine with Otto cycle is achieved so that very high pressure ratios are possible, what would be the impact on the automotive industry?

I am currently in first year engineering. I am doing a project on electronic fuel injection. The project requires as much physics incorporation as possible. I am just wondering if there is anybody who has some advise or ideas for me as far as "the physics of electronic fuel injection."...

Can anyone help me attempt such a project? I basically need to be able to sense the injection pulse in the injector pipe (1/4 inch / 6mm dia.) and convert it to an electrical pulse so that a normal ignition timing light (strobe light) can read the input as it would on a petrol/spark ignition...

Ring, field, injection, surjection, bijection, jet, bundle. Does anybody know who first introduced those terms and when and why those people called these matimatical structures so. I mean not the definitions but the properties of real things which can be accosiated with those mathematical...

I have a buddy asking if I can do this for his 300 ZX. I have checked and there is a programmable module available with software, but apparently some companies [one at least] are reprogramming the factory chip directly. Does anyone know where to get the code, or at least what values affect...

And we call ourselves "civilized". I say get rid of all of them. A Government has no business executing its' Citizens, for any reason.