Systems Definition and 1000 Threads

A system is a group of interacting or interrelated elements that act according to a set of rules to form a unified whole. A system, surrounded and influenced by its environment, is described by its boundaries, structure and purpose and expressed in its functioning. Systems are the subjects of study of systems theory.

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  1. K

    Control and Vibration of mechanical systems

    Homework Statement So I have this question given to me, basically there is a aero simulator which makes the ground shake so the data logger gets false readings, now to solve this problem a vibration absorption system has been added. Please see the attached System A.png file for the complete...
  2. T

    MHB A Quick Question About Orthornomal Systems of Functions and Fourier Series

    Two questions, actually. These just come from me doing a couple of problems on Fourier analysis from Rudin's text (I haven't actually taken a full course in the subject; we just spent about a week studying the topic in my real analysis class). (1) The Weierstrass Approximation Theorem...
  3. Z

    Matrix Linear Systems Equation

    Homework Statement Question in the image.Homework Equations I got a but can seem to get the answer for b which is $$\vec{x} = c\begin{pmatrix} 1 \\ 0\end{pmatrix}$$ where for any scalar c The Attempt at a Solution I managed to get it to $$\vec{x}(A-1)=0$$ $$= \begin{pmatrix} 0 3 \\ -1...
  4. C

    Top 3 CAD Systems - Find Out Which is Best & Why?

    Hello to everyone I am a CAD student. I am doing research into different CAD systems available. Could you please tell me what is the top 3 CAD systems available in the market today? I would like to ask out of these three CAD systems which is best & why? Please could you give me a brief...
  5. W

    Spring Mass System Problem Solutions: Check Here

    It's a mass spring system problem and I am just not sure if I am doing it right or not. If you could have a look at the problem attached and my solutions below and just let me know if I am doing it right or not 1)a) keq = k1 + k2 = 2355N/m b) keq = 1 / ((1/k1) + (1/k2)) = 451.0301N/m...
  6. Totalderiv

    How to Write a Linear System in Matrix Form

    Homework Statement Write the given system in the form x'=P(t)x + f(t) x'=-3y , y'=3x Homework Equations x'=P(t)x + f(t) x(t)=c_1x_1(t)+c_2x_2(t)+...+c_nx_n(t) The Attempt at a Solution I have no idea how to start this since my teacher never covered this in our notes and the book...
  7. R

    A quick and clever method for solving nonlinear systems of equations

    if we are given a polynomial s^6+as^5+bs^4+cs^3+ds^2+es+k (if a,b,c,d are known) what is a clever method to solving for the value k if we are given the following: the above polynomial is equal to the following(zeta is given as some constant, say 1 for simplicity)...
  8. T

    How could you improve waste heat recovery systems in cars coolants.

    What are the possibilities of using a waste heat recovery systems in the coolants of cars? Why is it not being done yet and how can it be improved?
  9. StevieTNZ

    Stillness of Systems: Physics Laws & Double-Slit Experiment

    Hi there, I'm not sure if I read somewhere - but if we see a system (macroscopic usually) and it looks still, is it actually not still? Is there a universal equation that governs how 'still' an object is? In the double-slit experiment, if we have the slits not being still, because we're...
  10. C

    What are the systems that I am comparing in this entropy problem

    I'm having trouble with understanding entropy, I'd just like a push in the right direction conceptually. relevant equations: delta S = S2 - S1 = Q/T = integral (dQ/T) If I have two bodies that when brought into contact obtain thermal equilibrium, is the change in entropy that I am...
  11. J

    Engine and control systems vs powertrain

    "engine and control systems" vs "powertrain" I am interested in working for a person in charge of "powertrains" on cars, and I have an interview for a co-op opportunity to work with someone in charge of aviation "engine and control systems" how much would these things overlap? i guess both...
  12. M

    Interested in Chaos Theory, Complex Systems, Nonlinear Systems

    As the thread title says I'm interested in Chaos Theory, Complex Systems, and Nonlinear Systems. If I can help it, I'd like to study these at graduate level. My question is what kind and how much mathematics I'm supposed to know if I'm to study these?
  13. G

    Question about relating basis of curvilinear coordinate systems.

    Wikipedia gives the relationship between a cartesian and curvlinear coordinate system as gi=(partial)x1/(partial)zi +(partial)x2/(partial)zi http://en.wikipedia.org/wiki/Curvilinear_coordinates Where gi is the i'th basis in the curvlinear coordinate system, x1 and x2 are the cartesian...
  14. P

    Application of Condensation Sequence to extrasolar systems?

    I have spent many hours today trying to determine at what distances certain substances will condense in protoplanetary disks around stars or temperatures different to that of our sun. I have come to the conclusion that the Inverse-Square Law is key to determining this. However, I am unsure as...
  15. H

    MHB Solution to complicated systems of three variables using matrices

    Hello,i have been trying to self-study matrices topics, during that I came across two complicated problems, and I wish I could provided with help to solve them : The question asks to solve each of the following system of equations, using row reduction method (Again...I assure that my teacher has...
  16. M

    Learning Systems Programming in C

    Hey everyone, I am currently in a C and UNIX Systems Programming course, and my professor is not the best to say the least. Does anybody have recommendations on how to learn Systems Programming on your own? Such as, any interesting projects I could do in my spare time with online...
  17. I

    Solving a systems of differential equations in terms of x(t) and y(t)

    Homework Statement x' ={{-1,1},{-4, 3}}*x, with x(0) = {{1},{1}} Solve the differential equation where x = {{x(t)}, {y(t)}} Homework Equations The Attempt at a Solution I have e^t*{{1},{-2}} + e^t*{{t},{2t+1}} but I'm not sure how to get it in terms of what it's asking.Edit: Please quick...
  18. C

    Why Single-wire earth return systems are only used in rural areas?

    Why Single-wire Earth return systems are only used in rural areas? Why not also in urban areas where there is only demand for single phase power?
  19. S

    Systems of Equations: Word Problem

    Homework Statement A small plane flying into the wind takes 3 h 20 min to complete a flight of 960km. Flying with the wind, the same plane takes 2 h 30 mins to make the trip. What is the speed of the plane? What is the speed of the wind? Homework Equations N/A The Attempt at a...
  20. M

    Conservative and non-conservative systems

    Homework Statement The potential energy (V) of a conservative system is a function of position (q) only. Thus, V = V(q) for any conservative system. When a conservative system interacts with radiation (spectroscopy), then the PE of the system depends explicitly on time (t) also: V =...
  21. T

    Futuristic space travel between star systems

    I am a writer of science fiction and I need to know some basics about space travel. I've read that it would take a ship 40 years to travel 1 parsec (3.26 light years) if the ship moved at 10% the speed of light. Does that sound right? Given that a futuristic ship could travel at this speed...
  22. S

    A question in communication systems and signals

    Hello. I have problem approaching the attached question and understanding how to solve it. I desperately need some help here. :confused: Thanks! :smile:
  23. S

    Resultant forces of coplanar systems

    Homework Statement Determine the magnitude of F if the resultant of the three forces passes through point O. Homework Equations ƩFx = 0 ƩFy = 0 ƩM = 0 The Attempt at a Solution The most I can come up with is that the two forces on the left would equal F on the right, and...
  24. B

    Does Every Linear System's Structure Predict Its Number of Solutions?

    1)Determine whether the given statement is true or false. A homogeneous linear system with the same number of equations as unknowns always has a unique solution. 2)Determine whether the given statement is true or false. If a linear system has no solution, the rank of the coecient matrix...
  25. M

    MHB Understanding Systems of DEs with Non-Zero $b(t)$

    Hi! Let's say we have a system of DEs $$ \begin{cases} \frac{dx}{dt} = y + e^t\\ \frac{dy}{dt} = x - t^2\\ \end{cases} $$ One would write it in matrix form and compute the eigenvectors and stuff like in this tutorial (can't post links due to low post count - it's from "Paul's online math...
  26. X

    Need help understanding this: Deriving expressions for spin 1/2 systems

    So this is my first quantum mechanics class and so far we have spent about a month (well 3 weeks) on just the mathematics. So in my book, the author explores the ideas presented by the stern gerlach experiment. It related the beam of silver atoms traveling through the separators to light...
  27. S

    Numerical evaluation of systems of ODEs

    I'm looking to do numerical evaluation of a system of differential equations and would like to use the RK4 method however I'm having a problem as my differential equations are respect to different variables and I don't know how to adapt RK4 to allow for that. The general form of the equations of...
  28. A

    Should I Major in Management Information Systems?

    I am attending a community college, and after this semester I will be done with my associates. However as of right now, my interest towards which subject I should major into has changed after reading more and more about other varieties of business oriented work. Accounting or Finance was my...
  29. J

    Resultants of Nonconcurrent Force Systems

    The question is to determine the magnitude, direction and sense of the resultant force of the nonconcurrent force system. Locate the resultant with respect to point O. I've looked at example in the book and tried to follow this problem as close to it as possible. (1)I first tried to find...
  30. S

    What angle will make the resultant of three forces vertical? [with picture]

    I have tried everything on this one that I can think of. I understand that the forces in the horizontal are 0, but I don't know where to start. says: determine the angle for which the resultant of the three forces is vertical. See Picture.
  31. X

    How to construct nonlinear ODE systems with given condition?

    I have a general question about how to construct nonlinear ODE systems with given condition such as # of critical points with certain characteristics of the phase portrait of each critical point. I have no problem solving any type of nonlinear ODE system. But to do the reverse order, I have...
  32. W

    Understanding Momentum Conservation in Isolated Systems

    I need the concept of momentum conservation in isolated systems described (in layman's terms,) as it pertains to the recoil of firearms, as described on this page. Bsharp.org : The Physics of Everyday Stuff : Gun Recoil I assume I am understanding it wrong, thinking he is saying that "while...
  33. X

    Exclusion Principle application to very large systems

    Hi, I've had something that's been bothering me for a while and I've been researching it, but I just want to clear something up. I understand that the exclusion principle dictates that fermionic particles with half-integer spin have an anti-symmetrical wavefunction under exchange, and...
  34. T

    Ideas for a thesis on dynamical systems?

    Hi there, I'm looking for a topic for my physics master thesis. The topic is free, and I'm really interested in (parallel) computing, as well as dynamical systems and "chaos". However, I'm kinda short on specific ideas, so this is where I'm looking for help. Current ideas for the project: 1)...
  35. J

    Free will and Emmy Noether's theorem of time invariant systems

    Hey all, Since first learning about Emmy Noether's proof that time invariant laws of physics imply conservation of energy, I can't shake the idea that this is the argument against the notion of free will. Here is my argument: By Noether's first theorem, whenever the laws are invariant in...
  36. N

    Farm water filtration and purification systems

    I'd like to see this topic that came up on Random Thoughts expanded. I have two rural water systems, both of which need some help. Any photos, brand names of pumps and filters, specs, would be greatly appreciated. http://img341.imageshack.us/img341/8291/img00030t.jpg
  37. J

    What is necessary to memorize for coordinate systems?

    I've been told that for upper level physics classes it's imperative to know how to switch between coordinate systems, however I'm unsure of what is exactly necessary to know. For example, today I was reading up on divergence and I noticed that there are formulas for divergence in spherical and...
  38. P

    How can the velocity at points of change in pipe systems be determined?

    For minor losses, I read that the pressure drop is equal to the dynamic pressure * loss coefficient. However, in calculating dynamic pressure, it uses a single velocity. How do you determine this velocity when it will vary at the point of change in pipe diameter or direction? I have read...
  39. M

    Planetary Systems within Elliptical Binary Stars?

    I read this article in Nature (http://www.nature.com/nature/journal/vaop/ncurrent/full/nature10768.html) as it describes two circumbinary planets. If it is assumed that most stars have a planet orbiting it and most Binary Star systems are elliptical, then wouldn't the majority of Binary Stars...
  40. B

    What is the most general solution for a 2-DOF system?

    Hi all, I have a question about Multi DOF vibrating systems. For free vibration of undamped MDOF systems, we have the equations of motion as : M \ddot{q} + K {q} = {0} (1) Where, M - n x n mass matrix K - n x n stiffness matrix {q} - n x 1 vector of generalized coordinates Most vibrations...
  41. G

    Linear Algebra - Solution Sets of Linear Systems

    See Attachment 2 for question or read below Describe and compare the solution sets of X_1 + 5 X_2 - 3 X_3 = 0 and X_1 + 5 X_2 - 3 X_3 = -2. See Attachment 1 for answer from back of book I do not understand how the answer in the back of the book answers the question or were to even begin to get...
  42. R

    Signals and Systems (System Properties)

    Homework Statement Indicate following properties for the system with the given input-output equation: -Linearity, Causality, Time Invariance, memoryless or not and explain why? Homework Equations y(t) = ∫t-∞ (t - λ) x(λ) dλ The Attempt at a Solution lets say X(t) is the...
  43. A

    How can I reduce the order of these troublesome ODE systems?

    Hi everybody, I've troubles with the following two systems of differential equations: image hosting gif I tried to reduce the order but I wasn't able to do anything...
  44. R

    MPPT systems + Solar Panels major doubts

    I'm working in the Power Systems team of CubeSAT. It is concerned with building a small student satellite with dimensions of 10x10cm. Our basic block diagram is as follows Solar panels-> In parallel Shunt Regulator -> Buck Converter->PRU (MAX8934A)->DC-DC Converters->Loads The shunt...
  45. U

    Variable-Mass Systems: Newton's 2nd Law

    Newton's second law gives that \sum\mathbf{F} = \frac{d\mathbf{p}}{dt} = \frac{d(m\mathbf{v})}{dt} In a system where mass varies with time, m(t), one would simply think that this would lead to \sum\mathbf{F} = m\frac{d\mathbf{v}}{dt} + \mathbf{v}\frac{dm}{dt} Yet everywhere online I...
  46. P

    The best books you suggest for (i)signals and systems (ii)electronic devices

    I've just started my [signals and systems] and [electronic devices and circuits] this sem...and i am learning that signals and systems topics are the core and fundamental concepts required for a electronic communication engineer... though i haven't found a great book that covers all the topics...
  47. A

    Forces and defining coordinate systems

    Homework Statement Homework Equations F=ma vi=vf + at The Attempt at a Solution If i was to define upward as positive y direction, would the answer be = -881 pounds (btw why is the answer in the image in Newtons?) and because i defined upward as +y would ƩF = T - w? where w = mg.
  48. pairofstrings

    Solving Non-Linear Systems with Higher Order Differential Equations

    Homework Statement In control engineering, I want to have a mathematical model of a physical system as a set of input, output and state variables related by higher order differential equations. 2. Relevant concepts As we all know that, in control engineering, we can solve linear-system...
  49. J

    Can misting systems improve HVAC efficiency?

    Hi Guys, I'm fairly new here, but I can't solve my problem (or I did but than I found a miracle) I'm trying to optimize a HVAC system, especially for dry and hot areas. Now I was thinking about the use of a misting system in front of the condensor as done by for instance these guys...
  50. S

    Linux Package to Simulate Mechanical Systems

    I want to start modeling mechanical systems, something say on the order of a motor, input torque only needed, driving a crankshaft that drives a piston. I'm looking to examine the forces generated in the crank, connecting rod and piston. I was wondering what open source Linux packages are...
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