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.
A new technique in cultivation by installing membrane sheet below the crop’s root zone was helped to save irrigation water in the root zone, less farm losses, increasing the field water use efficiency and water productivity. In this paper, the membrane sheet was installed below the root zone of zucchini during the summer growing season 2017 in open field. This research was carried out in a private field in Babil governorate at Sadat Al Hindiya Township reached 72 km from Baghdad. Surface trickle irrigation system was used for irrigation process. Two treatment plots were used, treatment plot T1 using membrane sheet and treatment plot T2 without using the membrane sheet. The applied irrigation water, time of
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Background: Pregnancy is a physiological condition that affects the general and oral health.It is also associated with an increase in oxidative stress, which may presispose to oral diseases including dental caries. Aim of the study: This study aimed to measure salivary protein carbonyl, glutathione peroxidase and selenium levels of women who are pregnant and their association with dental caries in comparison to non-pregnant women, and to find out the mostly affected biomarker of oxidative stress during pregnancy. Subjects, materials and methods: A cross-sectional research was performed for a samples of 30 pregnant and 30 non-pregnant women who were chosen from city of Baghdad's Primary Healthcare Centers. Both groups aged 25-30 years. In
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Cryptosporidiosis is mainly cause a persistent diarrhea in immune compromised patients, BALB/c mice have been suppressed by dexamethasone, tissue Th1, Th2 and Th17 cytokines concentrations in the ileum were significantly diminished in both infected and immunosuppressed mice. Level of IFN-g, TNF-a, IL-12, IL-6, IL-17A was increased in level, IL-4 didn’t increases, in both ileal and spleen tissue. Levels of above cytokines were examined in spleen in order to follow the proliferation of CD4+ T-cell during C. parvum infection.
Solid waste generation and composition in Baghdad is typically affected by population growth, urbanization, improved economic conditions, changes in lifestyles and social and cultural habits.
A burning chamber was installed to burn cellulosic waste only. It was found that combustion reduced the original volume and weight of cellulosic waste by 97.4% and 85% respectively.
A batch composting study was performed to evaluate the feasibility of co-composting organic food waste with the cellulosic bottom ash in three different weight ratios (w/w) [95/5, 75/25, 50/50].
The composters were kept in controlled aerobic conditions for 7 days. Temperature, moisture, and pH were measured hourly as process succe
... Show MoreThe residual limb within the prosthesis, is often subjected to tensile or fatigue stress with varying temperatures. The fatigue stress and temperatures difference which faced by amputee during his daily activities will produces an environmental media for growth of fungi and bacteria in addition to the damage that occurs in the prosthesis which minimizingthe life of the prosthetic limb and causing disconfirm feeling for the amputee.
In this paper, a mechanical and thermal properties of composite materials prosthetic socket made of different lamination for perlon/fiber glass/perlon, are calculated by using tesile test device under varying temperatures ( from 20oC to 60oC), also in this paper a device for measuring rotational bendin
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Non-orthogonal Multiple Access (NOMA) is a multiple-access technique allowing multiusers to share the same communication resources, increasing spectral efficiency and throughput. NOMA has been shown to provide significant performance gains over orthogonal multiple access (OMA) regarding spectral efficiency and throughput. In this paper, two scenarios of NOMA are analyzed and simulated, involving two users and multiple users (four users) to evaluate NOMA's performance. The simulated results indicate that the achievable sum rate for the two users’ scenarios is 16.7 (bps/Hz), while for the multi-users scenario is 20.69 (bps/Hz) at transmitted power of 25 dBm. The BER for two users’ scenarios is 0.004202 and 0.001564 for
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The purpose of this paper is to introduce a new type of compact spaces, namely semi-p-compact spaces which are stronger than compact spaces; we give properties and characterizations of semi-p-compact spaces.
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New mixed ligand complexes of New Schiff base 4,4'- ((naphthalen-1-ylimino) methylene) dibenzene-1,3-diol and 8-hydroxy quinoline: Synthesis, Spectral Characterization, Thermal studies and Biological Activities
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