flow and error control techniques wikipedia

... or duplicated segments. Error control in TCP is achieved by using a version of the Automatic Repeat reQuest (ARQ) error control protocols operating at DLL and it involves both error detection and retransmission ... protocols. 2.3.1 Stop -and- Wait ARQ The Stop -and- Wait ARQ error control mechanism is based on the Stop -and- Wait flow control. In its simplest form, the sender transmits a frame and it waits for ACK. ... proposed that concern congestion and error control for such environments. Following the discussion on IP multicast, Chapter 4 presents congestion and error control schemes and algorithms operating at...

Ngày tải lên: 26/10/2013, 17:15

... 112 Performance and applications 112 Direct torque control 113 3 D.C. motor drive control 114 Flux controller 114 Torque controller 115 Performance and applications 116 4 Analysis of and set up of a speed controller ... 109 Current control 109 Speed control 110 Performance and applications 110 Closed-loop induction motor drive 110 Flux calculator and reference-frame generation 111 Flux control 111 Performance and applications ... 326 Appendix A Standards for drives 329 A1 IEC (international) standards 330 Planned future IEC61800 standards 332 A2 CENELEC (EC) standards 332 A3 British standards 334 A4 IEEE (USA) standards 335 A5...

Ngày tải lên: 20/10/2013, 02:15

Ngày tải lên: 24/03/2014, 20:22

Ngày tải lên: 30/03/2014, 01:20

... Average throughput of nine UDP downlink flows and one TCP downlink flow (two greedy flows). Figure 19 Average throughput of two small UDP flows and two large UDP flows within the same station. Visoottiviseth ... contains one UDP uplink flow and one TCP downlink flow. Table 6 Experiment setup and Jain’s fairness index for greedy flows within a station Scenario no. Number of flows and its link direction ... downlink flow, (3) one UDP uplink flow with one TCP downlink flow, and (4) one TCP uplink flow with one TCP downlink flow. Figure 5 shows the average throughput of each flow in four cases. As we can...

Ngày tải lên: 20/06/2014, 22:20

... variables. Figure 1.3 Ball -and- plate integrator. 91239.indb 7 10/12/09 1:40:43 PM 8 ◾ Essentials of Control Techniques and Theory Computer simulation and discrete time control go hand in hand together. At ... 1:40:45 PM Essentials of Control Techniques and Theory 91239.indb 1 10/12/09 1:40:29 PM This page intentionally left blank 6 ◾ Essentials of Control Techniques and Theory a small sinusoidal ... of Control Techniques and Theory wend or for JavaScript or C: while (t < tmax){ H = H + (-k*H + u)*dt; t = t + dt; } Now the code has to be “topped” to set initial values for H, t, and u, and...

Ngày tải lên: 21/06/2014, 07:20

... 10/12/09 1:42:34 PM 78 ◾ Essentials of Control Techniques and Theory 7.2 Sine-Wave Fundamentals Sine-waves and allied signals are the tools of the trade of classical control. ey can be represented ... broader view. 91239.indb 77 10/12/09 1:42:21 PM 70 ◾ Essentials of Control Techniques and Theory i.e., for the same position control system, but with much reduced velocity feedback. You will ... 1:42:11 PM 82 ◾ Essentials of Control Techniques and Theory Now the derivative of a sine-wave is another sine-wave (or cosine-wave) of the same frequency, shifted in phase and probably changed in...

Ngày tải lên: 21/06/2014, 07:20

... ◾ Essentials of Control Techniques and Theory Since our motor is a simple two-integrator system with no damping, our state variables x and v will be simulated by x = x + x*dt and v = v + u*dt We ... computer control by sampling the error at intervals of 0.1 second, and applying a proportional corrective drive to the motor. Choose a suitable gain and discuss the response to an initial error. ... Essentials of Control Techniques and Theory We can save a lot of typing if we define the length of the stick to be one meter. To find the characteristic equation, we must then find the determinant and equate...

Ngày tải lên: 21/06/2014, 07:20

... ◾ Essentials of Control Techniques and Theory 10.2 Complex Planes and Mappings A complex number x + jy is most easily visualized as the point with coordinates (x, y) in an “Argand diagram.” In ... position error is now (command-x), so we can demand an angle of tilt tiltdem = c*(command-x)-d*vest; which we then constrain with if(tiltdem>.1){tiltdem=.1;} if(tiltdem< 1){tiltdem= 1;} and ... unscrambling sinusoids and we have seen how to analyze and control systems in terms of discrete time signals and transforms. is could be a good place to end a course in practical control. It is a...

Ngày tải lên: 21/06/2014, 07:20

... k + – 1 s(s+1) Output position Position demand Error Figure 12.1 Position control with variable feedback. 91239.indb 166 10/12/09 1:44:49 PM 148 ◾ Essentials of Control Techniques and Theory favorite. Soon time-domain and pseudo-random binary sequence ... 172 ◾ Essentials of Control Techniques and Theory 12.4 Plotting with Poles and Zeroes With the easy availability of computer power, the ability to plot a root locus by hand might seem have dubious ... But these coefficients represent the sum of the roots of Z and 91239.indb 174 10/12/09 1:45:01 PM 158 ◾ Essentials of Control Techniques and Theory Suppose that we wish to consider a variety of...

Ngày tải lên: 21/06/2014, 07:20

... Figure 16.7: 1. Controllable and observable 2. Controllable but not observable Controllable and observable Controllable but not observable Observable but not controllable Neither controllable nor ... of Control Techniques and Theory 3. Observable but not controllable 4. Neither controllable not observable Clearly any system model built to represent a transfer function must be both controllable ... controllable and observable—there is no point in adding uncontrollable or unob- servable modes. e control engineer is baffled by the fourth type of subset, some- what frustrated by sets two and three, and...

Ngày tải lên: 21/06/2014, 07:20

... 244 ◾ Essentials of Control Techniques and Theory and added a controller with state z, where  zKzLyMv=++ We apply signals from the controller dynamics, the command input and the system output ... settling—the sort of system that does not really need feedback control! 91239.indb 233 10/12/09 1:46:33 PM 230 ◾ Essentials of Control Techniques and Theory Now AB = −−             = −       01 12 0 1 1 2 so ... 15 1 + + s s 91239.indb 244 10/12/09 1:46:59 PM 248 ◾ Essentials of Control Techniques and Theory Now we have let a computer get in on the act, and the rules must change. x(t) is measured not continuously,...

Ngày tải lên: 21/06/2014, 07:20

... quantization errors. If a controller outputs a position demand to an analog position control subsystem, the command might require a great number of levels to define the target 0 1 Figure 20.2 Control ... z w w = + − 2 2 τ τ and finally the z-plane poles and zeros of the controller enable the controller code to be written. Q 19.5.1 In a system sampled 10 times per second, what discrete time controller ... integration. 91239.indb 276 10/12/09 1:48:00 PM 256 ◾ Essentials of Control Techniques and Theory and we are back in the world of eigenvectors and eigenvalues. If we can find an eigenvector x with its...

Ngày tải lên: 21/06/2014, 07:20

... the glide angle to control the speed, and to add extra thrust and energy to gain height; the roles of the throttle and aileron were reversed. Both control systems worked and maybe had the same ... 21.1. N1: e command input is subject to noise of various forms, from quantiza- tion of a numeric command to tolerances in encoding a control lever. is error is outside the loop and therefore ... value of the error. V(s) Y(s) G(s) H(s) U(s) F(s) – N(s) Figure 21.2 Control loop with disturbance noise. 91239.indb 291 10/12/09 1:48:22 PM 308 ◾ Essentials of Control Techniques and Theory 22.5...

Ngày tải lên: 21/06/2014, 07:20

... familiarity with many aspects of control theory, especially in the foundations in time and frequency domain and in methods of designing and analyzing linear systems and controllers. Many other topics ... 184 Ball and plate integrator, 6–7 Bang-bang control control law, 74 controller, 182 velodyne loop, 183 parabolic trajectories, 74 Bang–bang control and sliding mode, 74–75 Bellman’s Dynamic Programing, ... 292–295 PRBS, see Pseudo-random binary sequence (PRBS) Precision simulation, 6 Predictive control, 308 PSET commands, 12 Pseudo-random binary sequence (PRBS), 148, 212 Pseudo-random sequence illustration,...

Ngày tải lên: 21/06/2014, 07:20

... reversed or turned off. A and D on with B and C off will drive the motor one way while B and C on with A and D off will drive it the other way. By switching B and D on while A and C are off, braking ... it gives a tough control problem too. If we want to use a continuous controller, we have to consider integral control. Next time you stand in the shower, apply proportional control with a high ... values so that if the position error and velocity of the position control system are doubled, then the drive will also double. Double them again and again, and the drive can be increased without...

Ngày tải lên: 21/06/2014, 13:20

Ngày tải lên: 21/06/2014, 13:20

Ngày tải lên: 21/06/2014, 13:20

Ngày tải lên: 21/06/2014, 13:20

Ngày tải lên: 21/06/2014, 13:20