PC-based controller is an approach to control systems with Real-Time parameters by controlling selected manipulating variable to accomplish the objectives. Shell and tube heat exchanger have been identified as process models that are inherently nonlinear and hard to control due to unavailability of the exact models’ descriptions. PC and analogue input output card will be used as the controller that controls the heat exchanger hot stream to the desired temperature.
The control methodology by using four speed pump as manipulating variable to control the temperature of the hot stream to cool to the desired temperature.
In this work, the dynamics of cross flow shell and tube heat exchanger is modeled from step changes in cold water flow rate (manipulated variable). The model is identified to be First Order plus Dead Time (FOPDT).
The objective of this work is to design and implement a controller to regulate the outlet temperature of hot water that is taken as controlled variable. The comparison of the designed PI controller with the PC-Based controller performance (according to rise time, percentage overshoot and settling time) shows a good agreement for PC-Based to control the system.
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In this study the as-deposited and heat treated at 423K of conductive blend graphene oxide (GO)/ poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) thin films was prepared with different PEDOT:PSS concentration (0, 0.25, 0.5, 0.75 and 1)w/w on pre-cleaned glass substrate by spin coater. The XRD analysis indicate the existence of the preffered peak (001) of GO around 2θ=8.24° which is domain in all GO/ PEDOT:PSS films characterized for GO, this result approve the good quality of the PEDOT:PSS dispersion in GO, this peak shifted to the lower 2θ with increasing PEDOT:PSS concentration and after annealing process. The scanning electron microscopy (SEM) images and atomic force microscopy (AFM) clearly sh
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The solar energy is the major source of power for the future and an important source of renewable energy in Iraq and the world. Suitable climate conditions for solar energy are available in Iraq, especially the high temperature in the summer season which extends for more than six months in the year. Hence, the global solar radiation is abundant with high intensity, which is very essential in applicable models for researchers and solar applications. Therefore, nine first-order regression empirical equations of Angstrom-type correlations were used to estimate the more appropriate global solar radiation model for Baghdad city. Two equations were developed empirically in this work, using the most available and easy to get meteorological data
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Heat shock protein 70 (HSP70) is a crucial protein with vital biological tasks in cell continuation of life. The variation of HSP70 activation occurs as a consequence of stress that includes temperature states, toxicity, poisoning with heavy metals, and tumor-related conditions. One of the master jobs of the HSP family is the suppression of caspase-mediated apoptosis signals. A high level of the expression of HSP70 is accountable for tumorigenesis and resistance against chemotherapeutic drugs. For this reason, the detection of HSP70 may help to diagnose cancerous diseases. From the other side, targeting this chaperone might help in treatment by maintaining late caspase-dependent events. This study was conducted to detect the presenc
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The effect of thermal treatment on optical constants of pure PMMA and with addition (15 and 35) ml of coumarin at different temperatures (100, 110 and 120) C0 for 1 hour were investigated. Cast method used to prepares films of pure PMMA and PMMA with (15 and 35) of coumarin. UV/VIS spectrometer technique used to measure the absorption spectra for these films. The optical constant (absorption spectra and absorption coefficient) don’t changes after applied temperatures in pure PMMA film but the optical constant (absorption spectra and absorption coefficient) in PMMA with (15 and 35) ml of coumarin increased with applied temperatures. The optical energy gap of pure PMMA and PMMA with (15 and 35) ml of coumarin sl
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