Preferred Language
Articles
/
joe-668
The Experimental Assessment of R134a and Its Lower GWP Alternative R1234yf in an Automobile Air Conditioning System
...Show More Authors

Reducing global warming potential (GWP) of refrigerants is needed to the decrease of ozone-depleting of refrigeration systems leakages. Refrigerant R1234yf is now used to substitute R134a inside mobile air conditioning systems. Thermodynamic properties of R1234yf are similar to R134a. Also, it has a very low GWP of 4, compared to 1430 for R134a, making it a proper choice for future automobile refrigerants. The purpose of this research is to represent the main operating and performance differences between R1234yf and R134a. Experimental analysis was carried out on the automotive air conditioning system (AACS) with 3 kW nominal capacity, to test and compare the performance of R134a with R1234yf. Experiments were accomplished for both refrigerants in almost the same working conditions and procedure with a range of ambient temperature varied from 26oC to 50oC. Parameters studied were ambient temperature, type of refrigerant in the system at compressor speed 1450 rpm, and internal thermal loads of passenger room. The performance characteristics of the system, including COP and cooling capacity, were studied by changing different parameters. The results show that COP of R134a is higher than R1234yf by 12.6%, while the refrigeration effect of R134a is higher than R1234yf by 25%. This shows that R1234yf is a suitable and good candidate for drop-in replacement of R134a in AACS.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sat Jan 01 2022
Journal Name
Journal Of The Mechanical Behavior Of Materials
A spherical fuzzy AHP model for contractor assessment during project life cycle
...Show More Authors
Abstract<p>Measurement of construction performance is essential to a clear image of the present situation. This monitoring by the management team is necessary to identify locations where performance is exceptionally excellent or poor and to identify the primary reasons so that the lessons gained may be exported to the firm and its progress strengthened. This research attempts to construct an integrated mathematical model utilizing one of the recent methodologies for dealing with the fuzzy representation of experts’ knowledge and judgment considering hesitancy called spherical fuzzy analytic hierarchy process (SFAHP) method to assess the contractor’s performance per the project performance pa</p> ... Show More
View Publication
Scopus (8)
Crossref (8)
Scopus Clarivate Crossref
Publication Date
Wed Jan 01 2025
Journal Name
Lecture Notes In Networks And Systems
Using Artificial Intelligence to Enhance Digital Media Literacy Competencies and its Role in Shaping Media Students’ Awareness of Cybersecurity: A Survey Study
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Tue Feb 25 2020
Journal Name
Open Access Macedonian Journal Of Medical Sciences
Evaluation of Hepatocyte Growth Factor in Iraqi Patients with Acute Myeloid Leukemia: Its Correlation with Clinical Parameters and Response to Induction Therapy
...Show More Authors

BACKGROUND: Hepatocyte growth factor (HGF) is a proangiogenic factor that exerts different effects over stem cell survival growth, apoptosis, and adhesion. Its impact on leukemogenesis has been established by many studies. AIM: This study aimed to determine the effect of plasma HGF activity on acute myeloid leukemia (AML) patients at presentation and after remission. PATIENTS AND METHODS: This was a cross-sectional prospective study of 30 newly-diagnosed, adult, and AML patients. All patients received the 7+3 treatment protocol. Patients’ clinical data were taken at presentation, and patients were followed up for 6 months to evaluate the clinical status. Plasma HGF levels were estimated by ELISA based methods in the pa

... Show More
View Publication
Scopus (3)
Crossref (2)
Scopus Crossref
Publication Date
Wed Sep 15 2021
Journal Name
Conference: Rcsh-21at: Egitim Fakultesi, Akdeniz University- Turky
Mathematical Ability and its Relationship to Academic Resilience among Secondary School Students
...Show More Authors

The research aims to identify the relationship between mathematical ability and academic resilience among secondary school students. The research sample consisted of (280) students of the fourth scientific grade in secondary and preparatory schools of the General Directorate of Education in Baghdad / Karkh 2. The researchers built - based on previous studies and literature - a test of mathematical ability and a measure of academic resilience. The researchers used the T-test and Pearson's correlation coefficient to compare the results. The results revealed that fourth-grade students possessed mathematical ability and academic resilience. The research proved the existence of a positive correlation between mathematical ability and academic

... Show More
Publication Date
Sat Dec 30 2023
Journal Name
Journal Of The College Of Education For Women
Adaptive Response and its relation to Cognitive Appraisal among Secondary School Students
...Show More Authors

The current research's problem includes the impact of cognitive reappraisal and reformulate on self-experience of emotional response and its negative feelings and the activity of cognitive reappraisal in changing response. The aim of this research is to detect the relation between adaptive response and cognitive reappraisal upon students of secondary school, and to find differences in gender and stage. The sample contained male and female student for the year(2022-2023) and consists of (480) students (240) male and (240) female in the karkh education/ 1 To achieve this aims researcher used descriptive method and to measure the two variables researcher built a scale for adaptive response according to theory of compound emotion (Barrett,20

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Sep 26 2018
Journal Name
International Research Journal Of Pharmacy
DENTAL PHARMACOLOGICAL KNOWLEDGE AMONG IRAQI MOTHERS AND ITS IMPACT ON THEIR CHILDREN
...Show More Authors

View Publication
Crossref
Publication Date
Tue Oct 09 2018
Journal Name
Journal Of The College Of Education For Women
Nutrition Awareness among Middle School Students and its relation to some Variables
...Show More Authors

    The aim of the study was to identify the nutritional awareness of middle school students and its relation to some variables of the sample of the research according to the gender variable (male and female), the variable type of family and the variable achievement of the parents.       

      The descriptive approach was adopted and the sample of the study consisted of (795) male and female students who were selected by the random stratified method. The research tool was prepared based on the literature and previous studies. The food awareness measure in its final form was (25) after the data collection was processed using the appropriate statistical met

... Show More
View Publication Preview PDF
Publication Date
Wed Jan 01 2014
Journal Name
Pharmacology &amp;amp; Pharmacy
Gift Acceptance and Its Effect on Prescribing Behavior among Iraqi Specialist Physicians
...Show More Authors

View Publication Preview PDF
Crossref (18)
Crossref
Publication Date
Mon Jan 01 2018
Journal Name
Opcion
Fast-slow thinking and its relationship to cognitive failure At university students
...Show More Authors

Scopus
Publication Date
Tue Jul 11 2023
Journal Name
Journal Of Educational And Psychological Researches
Functional Engagement and Its Relationship to Hope-Based Thinking for Kindergarten Teachers
...Show More Authors

The research aims to identify the level of functional engagement and hope-based thinking of kindergarten teachers, identify if there is a significant difference in functional engagement and hope-based thinking in terms of specialization and years of service for kindergarten teachers, identify if there is a significant correlation between functional engagement and hope-based thinking of kindergarten teachers. The current research is determined by kindergarten teachers in the Second Rusafa Baghdad Education Directorate for the academic year (2022-2023). In order to achieve the objectives of the research, the researcher prepared a functional engagement scale, which consists of (45) items in three areas: Perceptual and functional engagement

... Show More
View Publication Preview PDF