Modeling the microclimate of a greenhouse located in Baghdad under its weather conditions to calculate the heating and cooling loads by computer simulation. Solar collectors with a V-corrugated absorber plate and an auxiliary heat source were used as a heating system. A rotary silica gel desiccant dehumidifier, a sensible heat exchanger, and an evaporative cooler were added to the collectors to form an open-cycle solar assisted desiccant cooling system. A dynamic model was adopted to predict the inside air and the soil surface temperatures of the greenhouse. These temperatures are used to predict the greenhouse heating and cooling loads through an energy balance method which takes into account the soil heat gain. This is not included in conventional methods. The results showed satisfactory agreement with published papers. Also, the results of heating and cooling loads obtained revealed good agreement with those obtained from conventional methods when the soil heat gain is included. Two identical collectors in series of total area of 5.4m2 were employed as a heating system which provides an outlet air temperature of 30 o C at air mass flux of 0.06 kg/s.m2 at midday in January. While, a 65 oC outlet air temperature was achieved for the same mass flux at midday in August. The desiccant cooling system
was operated in five operating modes; the ventilation mode and four recirculation modes with 20%, 50%, 70%,and 90% recirculation. The simulation results showed that a regeneration temperature of 60-70 o C is satisfactory for a cool supply air temperature of about 19.5 o C. Also, it was noted that 20-30 % recirculation of return air would result in suitable indoor greenhouse conditions for most periods of system operation. In addition, the coefficient of performance COP of the system was high compared with the conventional vapor compression systems.
In this present paper, an experimental study of some plasma characteristics in dielectric barrier discharge (DBD) system using several variables, such as different frequencies and using two different electrodes metals(aluminium (Al) and copper (Cu)), is represented. The discharge plasma was produced by an AC power supply source of 6 and 7 kHz frequencies for the nitrogen gas spectrum and for two different electrodes metals(Al and Cu). Optical emission spectrometer was used to study plasma properties (such as electron temperature ( ), electron number density ( ), Debye length ( ), and plasma frequency ( )). In addition, images were analysed for the plasma emission intensity at atmospheric air pressure.
This paper is concerned with introducing and studying the o-space by using out degree system (resp. i-space by using in degree system) which are the core concept in this paper. In addition, the m-lower approximations, the m-upper approximations and ospace and i-space. Furthermore, we introduce near supraopen (near supraclosed) d. g.'s. Finally, the supra-lower approximation, supraupper approximation, supra-accuracy are defined and some of its properties are investigated.
Theatrical techniques took upon themselves the responsibility of building and organizing the theatrical form for the various forms of performances, and it was the important tool that the show makers could rely on in carrying out the various works at the audio-visual level, and lighting is one of the most important elements of the visual formation of the image in the show, as it is related to the visual process and what it can achieve in operations The contrast that constitutes the aesthetic and intellectual values of the theatrical show, especially since the process of adjusting the element of time and the timings for receiving or delivering, moving, and the movement of the actor is what can determine the rhythm of the scene, which in it
... Show MoreIn the name of God the Merciful
Praise be to God and the Hall and Peace Uncle Prophet Muhammad and blindness Alo and companions
Money is the lifeblood and a reason for living. An individual cannot live without money to make it
It is only through the necessities of life and the state that it can perform its duties and functions only
As money is so important, the state must regulate the balance of revenues
And expenses in order to avoid failure in Mizanitia, but perhaps the country may be exposed to crises
An exception that leads to misappropriation in the general Mizanitia and the Islamic Shari'ah is valid for Makkah
Time and place for all circumstances has created several ways to address the budget defici
This research aims to investigate and improve multi-user free space optic systems (FSO) based on a hybrid subcarrier multiplexing spectral amplitude coding-optical code division multiple access (SCM-SAC-OCDMA) technique using MS code with a direct decoding technique. The performance is observed under different weather conditions including clear, rain, and haze conditions. The investigation includes analyzing the proposed system mathematically using MATLAB and OptiSystem software. The simulation is carried out using a laser diode. Furthermore, the performances of the MS code in terms of angles of bit rate, beam divergence and noise are evaluated based on bit error rate (BER), received
The main challenge of military tactical communication systems is the accessibility of relevant information on the particular operating environment required for the determination of the waveform's ideal use. The existing propagation model focuses mainly on broadcasting and commercial wireless communication with a highs transceiver antenna that is not suitable for numerous military tactical communication systems. This paper presents a study of the path loss model related to radio propagation profile within the suburban in Kuala Lumpur. The experimental path loss modeling for VHF propagation was collected from various suburban settings for the 30-88 MHz frequency range. This experiment was highly affected by ecological factors and existing
... Show MoreBACKGROUND: COVID-19 is resulted from severe acute respiratory syndrome coronavirus 2, which initiated in China in December 2019. Parasites are efficient immune modulators because their ability to stimulate an immune response in infected persons. AIM: This study aims to detect if there is a probable relationship between intestinal parasitic infections and COVID-19. METHODS: Ninety patients consulted at Al-Kindy Teaching Hospital (Al-Shifa center) from October 2020 till April 2021, confirmed infection with COVID-19 by PCR. Stool examination was done for detecting intestinal parasites. RESULTS: From 90 patients, males were 63 (70%), with median age 32 years, while females were 27 (30%), with age 24–44 years. Asymptomatic pati
... Show MoreBack ground: Visceral leishmaniasis is endemic in the
middle and south of Iraq, it involves mostly infants. The
disease is observed mainly among rural areas that are far
from equipped medical centers. Therefore, there is a need
for anon- invasive, cost- effective, reliable, easily
available and fast method of diagnosis of this dngerous
disease.
Objective: The aim was to compare the validity and
predictive values of the recombinant K39 antigen (rK39)
test with that of the indirect fluorescent antibody test
(IFAT) test (the usual laboratory method) in the detection
of visceral leishmaniasis.
Methods: A Cross-sectional study was done in ALMansour Pediatric Hospital (in AL-Rusafa), and Central
Pediatric
The present study was identified the type of bacterial contamination of Iraqi banknotes currency (Iraqi dinars) in circulation. 68 Iraqi banknotes currency of different denominations samples were randomly gathered from different locations and different occupational groups in Baghdad city. The results showed 61 (89.70%) of the samples were determined to be contaminated with bacteria, whereas 7 (10.29%) were confirmed to be sterile. A total of 11 different species of bacteria resulting in 72 isolates were found from those 61 contaminated Iraqi banknotes currency. Based on culture, morphological and biochemical tests, 11 isolates were identified as Bacillus sp., Staphylococcus aureus, Staphylococcus epidermidis, Corynebacterium diphtheria, Leu
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