In all process industries, the process variables like flow, pressure, level, concentration
and temperature are the main parameters that need to be controlled in both set point
and load changes.
A control system of propylene glycol production in a non isothermal (CSTR) was
developed in this work where the dynamic and control system based on basic mass
and energy balance were carried out.
Inlet concentration and temperature are the two disturbances, while the inlet
volumetric flow rate and the coolant temperature are the two manipulations. The
objective is to maintain constant temperature and concentration within the CSTR.
A dynamic model for non isothermal CSTR is described by a first order plus dead
time (FOPDT).
The conventional PI and PID control were studied and the tuning of control
parameters was found by Ziegler-Nichols reaction curve tuning method to find the
best values of proportional gain (Kc), integral time ( I) and derivative time ( D).
The conventional controller tuning is compared with IMC techniques in this work and
it was found that the Ziegler –Nichols controller provides the best control for the
disturbance and the worst for the set-point change, while the IMC controller results
show satisfactory set-point responses but sluggish disturbance responses because the
approximate FOPTD model has relatively small time delay.
Feedforward and feedforward combined with feedback control systems were used as
another strategy to compare with above strategies. Feedforward control provides a
better response to disturbance rejection than feedback control with a steady state
deviation (offset). Thus, a combined feedforward-feedback control system is preferred
in practice where feedforward control is used to reduce the effects of measurable
disturbances, while feedback trim compensates for inaccuracies in the process model,
measurement error, and unmeasured disturbances. Also the deviation (offset) in
feedforward control was eliminated.
This paper proposes a new method to tune a fractional order PID controller. This method utilizes both the analytic and numeric approach to determine the controller parameters. The control design specifications that must be achieved by the control system are gain crossover frequency, phase margin, and peak magnitude at the resonant frequency, where the latter is a new design specification suggested by this paper. These specifications results in three equations in five unknown variables. Assuming that certain relations exist between two variables and discretizing one of them, a performance index can be evaluated and the optimal controller parameters that minimize this performance index are selected. As a case study, a third order linear time
... Show MoreZiegler and Nichols proposed the well-known Ziegler-Nichols method to tune the coefficients of PID controller. This tuning method is simple and gives fixed values for the coefficients which make PID controller have weak adaptabilities for the model parameters variation and changing in operating conditions. In order to achieve adaptive controller, the Neural Network (NN) self-tuning PID control is proposed in this paper which combines conventional PID controller and Neural Network learning capabilities. The proportional, integral and derivative (KP, KI, KD) gains are self tuned on-line by the NN output which is obtained due to the error value on the desired output of the system under control. The conventio
... Show MoreThis paper proposes a new method to tune a fractional order PID controller. This method utilizes both the analytic and numeric approach to determine the controller parameters. The control design specifications that must be achieved by the control system are gain crossover frequency, phase margin, and peak magnitude at the resonant frequency, where the latter is a new design specification suggested by this paper. These specifications results in three equations in five unknown variables. Assuming that certain relations exist between two variables and discretizing one of them, a performance index can be evaluated and the optimal controller parameters that minimize this performance index are selected. As a case study, a thir
... Show MoreThe aim of the current research is to identify the self-control of kindergarten teachers as well as to identify the significance of the differences according to a variable (years of service, academic achievement, specialization). Its final paragraphs consist of (35) paragraphs, and its psychometric properties were verified and the tool was applied to a sample of (400) teachers chosen randomly from kindergarten teachers affiliated to the General Directorates of Education in Baghdad, Rusafa, and Karkh for the academic year 2019-2020
In light of the objectives of the current research, the following results were reached
- The current research sample is from kindergarten teachers with self-contro
- There are diffe
The term “non-violence” is a means of political, social, and advocacy that excludes force in reaching its objectives, and lacks infringement of the rights of non-violence. The policy of non-violence is a beautiful logic of the whole of Islamic creation, in that it is an integral part of the whole structure of Islam and it is a policy of brilliant and brilliant saying in the Almighty: `` Neither level nor good or bad, pay what is better, If that between you and him enmity as if he were intimate guardian (Suratvsalat, verse: 34. Has According to the prophet of Islam, it means that God gives to kindness (kindness) what does not give to violence (Sunan Abu Dawood, 4/255). These terms accurately communicate what is meant by violence and n
... Show MoreThe aim of this research is to study the factors affecting drag coefficient (C d ) in
non-Newtonian fluids which are the rheological properties ,concentrations of non-
Newtonian fluids, particle shape, size and the density difference between particle and
fluid .Also this study shows drag coefficient (C d ) and particle Reynolds' number (Re
P ) relationship and the effect of rheological properties on this relationship.
An experimental apparatus was designed and built, which consists of Perspex pipe
of length of 160 cm. and inside diameter of 7.8 cm. to calculate the settling velocity,
also electronic circuit was designed to calculate the falling time of particles through
fluid.
Two types of solid particles were
This research is an attempt to achieve the following objectives: 1. identifying the nature of the non-verbal communication skills practiced by educational counselors in individual guidance. 2. Identifying the significant differences between non-verbal communication skills exercised by educational counselors from their point of view in regard to their gender (male-female). The researcher used a questionnaire as a tool prepared based on exploratory questions of educational counselors and literature. It has consisted of (26) items over four domains applied to a sample of (50) educational counselors (male and female) who have been chosen randomly from schools located in Baghdad Education Directorate Rusafa / 2. It was treated statistically u
... Show MoreThis paper proposes a new structure for a Fractional Order Sliding Mode Controller (FOSMC) to control a Twin Rotor Aerodynamic System (TRAS). The new structure is composed by defining two 3-dimensional sliding mode surfaces for the TRAS model and introducing fractional order derivative integral in the state variables as well as in the control action. The parameters of the controller are determined so as to minimize the Integral of Time multiplied by Absolute Error (ITAE) performance index. Through comparison, this controller outperforms its integer counterpart in many specifications, such as reducing the delay time, rise time, percentage overshoot, settling time, time to reach the sliding surface, and amplitude of chattering in control inpu
... Show MoreA Wearable Robotic Knee (WRK) is a mobile device designed to assist disabled individuals in moving freely in undefined environments without external support. An advanced controller is required to track the output trajectory of a WRK device in order to resolve uncertainties that are caused by modeling errors and external disturbances. During the performance of a task, disturbances are caused by changes in the external load and dynamic work conditions, such as by holding weights while performing the task. The aim of this study is to address these issues and enhance the performance of the output trajectory tracking goal using an adaptive robust controller based on the Radial Basis Function (RBF) Neural Network (NN) system and Hamilton
... Show MoreThis study aims to investigate the types of impoliteness strategies used in Putin's speech at the annexation ceremony. All of Putin's speeches were intentionally delivered to cause damage to the hearers' negative and positive faces. Culpeper's (2011) classifications of impoliteness, which consist of five strategies that are the opposite of politeness, were adopted. The data were collected from the President of Russia, providing a rich source for analysis. Qualitative and quantitative analyses were employed to achieve the study objectives. Qualitative analysis allowed for a detailed examination of the impoliteness strategies employed, while quantitative analysis provided a broader understanding of their frequency and distribution. Putin most
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