Preferred Language
Articles
/
joe-2598
Influence of Aging Time on Asphalt Pavement Performance
...Show More Authors

Aging of asphalt pavements typically occurs through oxidation of the asphalt and evaporation of the lighter maltenes from the binder. The main objective of this study is to evaluate influence of aging on performance of asphalt paving materials.nAsphalt concrete mixtures, were prepared, and subjected to short term aging (STA) procedure which involved heating the loose mixtures in an oven for two aging period of (4 and 8) hours at a temperature of 135 o C. Then it was subject to Long term aging (LTA) procedure using (2 and 5) days aging periods at 85 o C for Marshall compacted specimens. The effect of aging periods on properties of asphalt concrete at optimum asphalt content such as Marshall Properties, indirect tensile strength at 25 o C, Resilient Modulus and resistance to permanent deformation were evaluated. The impact of Short-term and long-term aging on asphalt concrete properties was evaluated. The stiffness of the mixture increases by increasing aging period that lead to increase of Marshall Stability, indirect tensile strength, and the resilient modulus, which leads to increases the resistance of mixtures against permanent deformation. The 8 hr. short term aging causes the Marshall stability, indirect tensile strength at 25 o C and resilient modulus to be increased by 52%, 34 % , 20% respectively as compared with control mixture while, the permanent deformation decreased by (33 %) as compared with control mixture.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Oct 03 2022
Journal Name
Physica Scripta
Radiation shielding properties of Cd-Bi-Pb-Zn-borate glasses: influence of Bi<sub>2</sub>O<sub>3</sub> activation
...Show More Authors
Abstract<p>We report the detail characterizations and <italic>γ</italic>-radiation protecting characteristics of some new types of cadmium (Cd)-bismuth (Bi)-lead (Pb)-zinc (Zn)-borate glasses of the form (70-x)B<sub>2</sub>O<sub>3</sub>-10ZnO-10PbO-10CdO-xBi<sub>2</sub>O<sub>3</sub> (with x = 0 to 20 mol%) synthesized via melt-quenching process. The influence of various Bi<sub>2</sub>O<sub>3</sub> contents on the <italic>γ</italic>-radiation shielding traits of the obtained glass samples was evaluated by exposing them at different <italic>γ</italic>-ray energies (0.356, 0.662, 1.173, and 1.33 MeV) whic</p> ... Show More
View Publication
Scopus (7)
Crossref (7)
Scopus Clarivate Crossref
Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Performance Estimation of Heat Exchanger Operates By Evaporative Cooling Manner
...Show More Authors

        In this study the design and installation of evaporative air cooler was carried out using completely outdoor air (fresh air) according to two stage evaporative cooling principle. The laboratory equipment was installed by designing and manufacturing a cross flow plate heat exchanger, where aluminum plates used for this purpose with dimensions (50 × 30 × 40 cm). The surfaces of heat exchanger were covered by sawdust from wetted channels side, to increase the percentage of wetting these surfaces and hence improve the performance and efficiency of air cooler.

        An experimental study was carried out to estimate the performance of cooling system, where som

... Show More
View Publication Preview PDF
Publication Date
Thu Dec 01 2022
Journal Name
Civil And Environmental Engineering
Performance of Prestressed Concrete Hunched Beams with Multi-Quadrilaterals Openings
...Show More Authors
Abstract<p>A long-span Prestressed Concrete Hunched Beam with Multi-Quadrilateral Opening has been developed as an alternative to steel structural elements. An experimental program was created and evaluated utilizing a single mid-span monotonic static load on simply supported beams, which included six beams with openings and the solid control beam without openings, to investigate the performance of such beams. The number and height of the quadrilateral openings are the variables to consider. According to test results, the presence of openings in the prestressed concrete hunched beam with multi-quadrilateral opening did not considerably affect their ultimate load capacity with respect to a contro</p> ... Show More
View Publication Preview PDF
Scopus (2)
Crossref (2)
Scopus Clarivate Crossref
Publication Date
Sat Mar 30 2013
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Studying the Performance of Refrigeration Units Powered by Solar Panel
...Show More Authors

An experimental study was conducted to determine the performance of a solar electric refrigeration system. The system contained flat photovoltaic solar panel which absorbs the solar energy and convert it to electrical energy, used to run the refrigeration cycle. Two refrigeration cycles with electrical solar panel were used over a period of 12 months, the first one with classical parts known in refrigeration cycle, while the second one introduced heat exchanger which improves the coefficient of performance by saving the consumed energy. The coefficient of performance of these refrigeration cycles with compressor efficiency 85% are 2.102 and 2.57 respectively. The overall efficiency of the two systems are 18.9% and 23.13%.

View Publication Preview PDF
Publication Date
Thu Mar 30 2023
Journal Name
Journal Of Economics And Administrative Sciences
Role of Balanced Scorecard in Evaluating Total Productive Maintenance Performance
...Show More Authors

              In light of the general inadequacy in the performance of the economic units operating in Iraq, and the contemporary developments in all the various sciences, Iraqi economic units have become obligated to use modern technologies applied around the world. Keeping abreast of these developments is done by moving away from traditional methods of evaluating performance and applying approved and accepted methods of evaluating performance. This will lead to an increase in the efficiency and effectiveness of the activities of economic units. In addition, this drives to reduce production costs. Accordingly, this study aims to clarify the application of the balanced scor

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Oct 01 2018
Journal Name
Journal Of Engineering
Performance of Self-Compacting Concrete Slab with Grinded Local Rocks
...Show More Authors

The effect of using grinded rocks of (quartzite and porcelanite) as powder of (10 and 20) % replacement by weight of cement for self-compacting concrete slabs was investigated in this study. Five slabs with 15 concrete cubes were tested experimentally at 28 days to study the compressive strength, ultimate load, ultimate deflection, ductility, crack load and steel strain. The test results show that, the compressive strength improvement when replacement of local rock powder reached to (7.3, 4.22) % for (10 and 20) % quartzite powder and (11.3, 16.1) % for (10 and 20) % porcelanite powder, respectively compared to the reference specimen. The ultimate load percentage increase for slabs with (10 and 20) % rep

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
The Role of Computerized Knowledge Operations in Improving Business Performance
...Show More Authors

This research aimed at studying the role of calculated knowledge an its efficiency in improving the performance especially most of the organizations are living within knowledge era which concentrate on new technology investment in different fields of modern live . Under the scientific trends towards the economy of calculated knowledge which depend basically on new computer program in order to utilize the knowledge to raise the level of work performance exploiting different resources in the best way that helps the organizations to achieve their objectives because the information technology and computer programs became a means of survival and indispensible instrument within the developed world which depend on prosperity . progress

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Jan 30 2020
Journal Name
Journal Of Engineering
The Optimum Reservoir Performance of Nahr Umr/Ratawi Oil Field
...Show More Authors

Reservoir study has been developed in order to get a full interesting of the Nahr Umr formation in Ratawi oil field. Oil in place has been calculated for Nahr Umr which was 2981.37 MM BBL. Several runs have been performed to get matching between measured and calculated of oil production data and well test pressure. In order to get the optimum performance of Nahr Umr many strategies have been proposed in this study where vertical and horizontal wells were involved in addition to different production rates. The reservoir was first assumed to be developed with vertical wells only using production rate of (80000–125000) STB/day. The reservoir is also proposed to produce using horizontal wells besides vertical wells with production rat

... Show More
Crossref
Publication Date
Sat Aug 18 2018
Journal Name
Journal Of Engineering And Applied Sciences
Performance Evaluation of Transport Protocols for Mobile Ad Hoc Networks
...Show More Authors

Mobile Ad hoc Networks (MANETs) is a wireless technology that plays an important role in several modern applications which include military, civil, health and real-time applications. Providing Quality of Service (QoS) for this application with network characterized by node mobility, infrastructure-less, limitation resource is a critical issue and takes greater attention. However, transport protocols effected influential on the performance of MANET application. This study provides an analysis and evaluation of the performance for TFRC, UDP and TCP transport protocols in MANET environment. In order to achieve high accuracy results, the three transport protocols are implemented and simulated with four different network topology which are 5, 10

... Show More
View Publication
Publication Date
Wed Jan 01 2020
Journal Name
Aip Conference Proceedings
Investigation hydraulic performance of splash fills packing in cooling tower
...Show More Authors

Heat is one of the most energy forms emitted to atmosphere by industrial processes. Water is considered to be the best material to reduce heat energy since its available in nature in abundance and has the ability to absorb heat efficiently. Cooling towers are ideal alternatives to re-cool hot water instead of throwing it especially in places that lack natural water resources or when there are environmental precautions because water with high temperature would be harmful to the ecosystem when it recycled to natural resources such as rivers and lakes. Also, cooling towers considered economically feasible when using west water. This paper interests with hydraulic characteristics of a counter flow wet cooling tower which was investigated experi

... Show More
View Publication
Scopus (6)
Crossref (3)
Scopus Crossref