Farah Saoud; Sajad Hussein Abdali; Essam Esmail
Abstract
Planetary gear-cam mechanisms (PGCMs) are mechanisms that combine planetary gears and cams. Despite the fact that these systems have the ability to achieve a wide variety of periodic motions of the output link, they have received little attention. To generate and classify PGCMs, structural properties ...
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Planetary gear-cam mechanisms (PGCMs) are mechanisms that combine planetary gears and cams. Despite the fact that these systems have the ability to achieve a wide variety of periodic motions of the output link, they have received little attention. To generate and classify PGCMs, structural properties must first be identified. The classification of gear-cam mechanisms is studied, as are their functional, structural, and graph representations. PGCMs are classified based on their number of degrees of freedom, number of links, and joint types. They are synthesized utilizing the spanning tree-based approach to build the entire set of gear-cam graphs. The relation between graphs and PGCMs is investigated and many graph fundamentals are converted into PGCMs. The atlas of five-vertex graphs is obtained, allowing the development of a large number of mechanisms. The precise results of the 5-link PGCM graphs have been confirmed to be 12. The application and significance of this approach in producing a variety of non-uniform motions, developing better alternatives, and creating new designs for variable-speed output mechanisms are demonstrated.
Mukhalad Muayada; Hussein Jannaa
Abstract
One of the main problems in the city of Diwaniyah is finding suitable places for burying waste. Geographic Information System (GIS) is an appropriate tool used for this purpose. The city of Diwaniyah, like other Iraqi governorates, is not equipped with an organized system for burying urban waste. The ...
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One of the main problems in the city of Diwaniyah is finding suitable places for burying waste. Geographic Information System (GIS) is an appropriate tool used for this purpose. The city of Diwaniyah, like other Iraqi governorates, is not equipped with an organized system for burying urban waste. The main objective of this study is to find the optimal site for the landfill in Al-Diwaniyah City. For this purpose, and by using the multi-criteria decision analysis (MCDA) known as the Analytical Hierarchy (AHP) in the GIS environment, eleven criteria were presented in the first phase according to international determinants and standards and in line with Iraqi standards. The environment, which is (river, slope, agricultural land use, groundwater, railways, power line, roads, soil types, city center, gas pipeline, and villages) through which a map was developed and produced for each standard using several tools and models in GIS environment, in the second phase, we resorted to the capacity improvement program matrix to assess the weights of the eleven criteria. The study concluded two landfill sites Using the spatial analysis tool "Weight Overlay", the first site is located at coordinate UTM (502241.5, 3537336.2) east of the city, with an area of about 18.89 km2, while the second site is located at coordinate UTM (503371, 3528215.7) to the south of the city, with an area of about 20.64 km2.
Manar A. Abdulrahman; Suha I. S. Al-Ali; Mohammed Nsaif Abbas
Abstract
This article delves into the intricate dynamics of groundwater flow within duct systems, examining both critical and sub-critical flow conditions. Employing mathematical models, sophisticated potential methodologies, numerical simulations, and flow net analysis, the research investigates ...
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This article delves into the intricate dynamics of groundwater flow within duct systems, examining both critical and sub-critical flow conditions. Employing mathematical models, sophisticated potential methodologies, numerical simulations, and flow net analysis, the research investigates the behaviour of the phreatic surface under varying flow coefficients and slope angles . Noteworthy discoveries include the significant influence of the flow coefficient on the curvature and deflection of the phreatic surface, with higher m values resulting in steeper slopes. Additionally, the study emphasizes that changes in slope angle θ impact the interface's shape, leading to variations in flow depth. Innovative visualizations incorporating streamlines and velocity potential contours offer insights into flow patterns, recirculation zones, and potential turbulence areas. These critical finding supply essential insights for enhancing environmental strategies, optimizing water resource management, and improving the efficiency of fluid systems. The study emphasises how important it is to use flow net analysis and thoroughly investigate critical and sub-critical flow scenarios in order to handle issues related to groundwater management and sustainability. Stakeholder can enhance their capacity for fluid system optimization by applying these analytical tools, leading to improved environmental outcomes and informed decision-making.
Naseer Hamza; Haider A. Abdul kazem
Abstract
In this paper highlights the most significant recent developments in scientific study on Heat sinks are thermal management components made of materials with sufficient thermal conductivity qualities. Due to the increase in operating power and speed as well as the general reduction in system size, the ...
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In this paper highlights the most significant recent developments in scientific study on Heat sinks are thermal management components made of materials with sufficient thermal conductivity qualities. Due to the increase in operating power and speed as well as the general reduction in system size, the issues of heat removal and temperature management have taken on increasing importance in these studies. Changing the geometry of extended surfaces, the material from which they were made, the working fluid that ran over them and or the dimension of the channel, are some of the subcategories in which studies have been conducted. The current review addresses the main recent findings in the forced convection heat transfer happened at laminar flow inside small scale diameters channels. The recent studies indicated a remarkable enhancement with the change of Re, D and internal geometry of channel. The configuration of flow passages also adopted as a different passive technique to enhance thermal fluid flow.
Sajad Hussein Abdali; Farah Mohammed Saoud; Essam Esmail
Abstract
Several approaches for detecting isomorphism in kinematic chains have been developed in recent literature. If two kinematic chains have a 1-1 correspondence and their incidences are maintained, they are isomorphic. In this work, a matrix-based method for identifying isomorphism is presented. The new ...
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Several approaches for detecting isomorphism in kinematic chains have been developed in recent literature. If two kinematic chains have a 1-1 correspondence and their incidences are maintained, they are isomorphic. In this work, a matrix-based method for identifying isomorphism is presented. The new method is based on fundamental circuits, vertex degrees, and spanning trees. A unique identifier for isomorphic graphs is proposed. Two graphs are isomorphic if their isomorphic identification numbers have the same value. This reduces the structural isomorphism test to a comparison of the isomorphic identification numbers of the two graphs under consideration. Regardless of vertex labeling of the graphs, which is problematic in other ways, similar isomorphic identification numbers are generated for isomorphic graphs. The new method is a comprehensive, systematic way for detecting isomorphism during the synthesis of kinematic chains. Isomorphic graphs are identified regardless of graph representation. The new approach is verified by the atlas of 6-link 2- degree of freedom planetary gear mechanisms (PGMs), the atlas of 5-link 2-degree of freedom planetary geared cam mechanisms (PGCMs) as well as some PGMs and PGCMs.
Muhammed Abdulhasan Muhammed; Nabeel Almuramady
Abstract
In reality, there are a number of tiny contact asperities on the contact surface, which may be seen at the micro/ nano scales. The total mechanical behavior is the product of all asperities that are involved during the contact. There are still a lot of unresolved issues in the study of contact and dry ...
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In reality, there are a number of tiny contact asperities on the contact surface, which may be seen at the micro/ nano scales. The total mechanical behavior is the product of all asperities that are involved during the contact. There are still a lot of unresolved issues in the study of contact and dry friction behavior of rough surfaces because of the variety of surface topography, complexity of the contact scale, and nonlinearity of the constitutive materials. The complexity of the friction mechanism and its misunderstood nature pose significant challenges in this study. This paper provides a comprehensive review of typical dry friction behaviors observed at the micro- and nanoscales. The significance of surface roughness, the role of contact mechanics, and the impact of experimental and theoretical approaches in modeling and simulation have been examined at this study. Additionally, the manuscript highlights the crucial role of proximal probing techniques, particularly the Atomic Force Microscopy (AFM) technique.
Ahmed Ali Shakir Al-Saadi
Abstract
The dissipation of excessive heat flux is presently a significant issue that needs to be addressed due to the use of microdevices in fields such as nuclear energy, electronic devices, aerospace engineering, building engineering, and more. Because their increased heat transfer and compact size, microchannel ...
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The dissipation of excessive heat flux is presently a significant issue that needs to be addressed due to the use of microdevices in fields such as nuclear energy, electronic devices, aerospace engineering, building engineering, and more. Because their increased heat transfer and compact size, microchannel cooling systems have become an effective way to manage the temperature of microdevices and equipment upgrades. However, due to the increasing demands placed on microdevices for thermal load, controlling the temperature, and conserving energy, efficient heat exchangers, in particular microchannels, are attracting a growing amount of interest. A key passive technique for successfully increasing the heat transfer of the microchannel cooling system and improving the performance of microchannels is channel shape optimization. Therefore, the characteristics of microchannel geometry from prior research has been reviewed, categorized, and summed up in this article. The analysis focuses primarily on structural features and microchannel geometry attributes that enhance the impact of pressure drop and heat transfer. It also presents the relationship between boiling heat transfer and the geometrical features of microchannel flow and discusses the potential study directions for microchannel geometry design. The current review of microchannels will provide researchers working on these microchannel components with specialized expertise. In an effort to improve the impact of heat transfer, this study reviews, categorizes, and summarizes the characteristics of prior studies' microchannel geometry.
Suroor Jasim; Emad Hani Ismaeel
Abstract
For the protection of historic city identity and providing a sustainable benefit to its buildings,the strategy of conserving heritage buildings in old cities through their reuse is complex and crucial.The most appropriate mechanism for reuse is the most widely used mechanism for preserving and enhancing ...
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For the protection of historic city identity and providing a sustainable benefit to its buildings,the strategy of conserving heritage buildings in old cities through their reuse is complex and crucial.The most appropriate mechanism for reuse is the most widely used mechanism for preserving and enhancing the values of heritage buildings.To extend the physical and functional life of heritage buildings and avoid the damage that may be caused as a result of wrong decisions,this study assists decision-makers in making the best decision more accurately, quickly,and effectively to reuse heritage buildings.Due to the lack of knowledge of the criteria and indicators that affect the most appropriate reuse process on a large scale and the extent to which they affect the process of selecting the most appropriate use,this paper aims to extract such criteria and indicators and prove their effectiveness in the process of selecting the most appropriate reuse of heritage buildings in old cities.The procedure of the study includes three phases:the 1st phase analyzes previous related studies and international charters,then extracts the most important criteria and indicators;the 2nd phase deals with expert interviews to provide a criteria assessment according to significance;and the 3rd phase applies these criteria and indicators to historic buildings in Mosul's old city to evaluate the possibility of their use.Adecision-making methodology(AHP)is applied using Microsoft Excel.The methodology was applied to Ziyadah House and Suleiman Al-Sayegh House.In the results,the application to arrange the optimal alternatives showed that the Ziadah house got the highest value,while the Al-Sayegh house got the lowest value.
Shayan Shero Ahmed; Mand Ibrahim Dizayee
Abstract
Due to urbanization, it has been found that public open spaces shared in the city is not maintained in many cases, as new investments are trying to get use of the land to construct more buildings, same tendency has been noticed with residential estates. The treatment for the shortages of public open ...
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Due to urbanization, it has been found that public open spaces shared in the city is not maintained in many cases, as new investments are trying to get use of the land to construct more buildings, same tendency has been noticed with residential estates. The treatment for the shortages of public open spaces can be achieved by providing sufficient private open spaces in housing estates. Furthermore, it is important for the designers to consider the dwelling layout to provide the best environment for the residents; this will be through maintaining high level of household satisfaction. One main element of household satisfaction is open spaces. In this research paper, private open space assessments in 4 investment projects with 98 samples were approached in Erbil. To investigate and examine how the exterior environment of the dwellings affects the residents’ satisfaction, based on plot size and number of bedrooms that been performed by survey on selected projects through documentation survey and questionnaire. The evaluation had been performed through two stages, first the technical assessment according to Iraqi standards, and second resident’s response regarding satisfaction level. The research objectives obtained using SPSS software, through using descriptive statistics, correlation and regression analysis, the results of the research discovered that all the projects except Minara B were in the range of Iraqi standards, slightly above minimum level. Moreover, the level of overall satisfaction with these projects started from neutral to slightly satisfied, but residents have responded that they need some more parts of private open spaces.
ghaidaa kareem rahi; Dhafer Abdul Amir Hamzah
Abstract
This study reveals the increase in heat transfer using passive and active techniques for BFS. Backward-
facing step (BFS) flow is one example of a representative model for separation flows which has been
noted in its applications in engine flows, vehicles, condensers, heat transfer systems, and flow ...
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This study reveals the increase in heat transfer using passive and active techniques for BFS. Backward-
facing step (BFS) flow is one example of a representative model for separation flows which has been
noted in its applications in engine flows, vehicles, condensers, heat transfer systems, and flow around
structures, aerodynamic flows. To learn about the importance of backward-facing step flow from a
theoretical and engineering perspective, this work provides a comprehensive review of heat transfer and
flow results of forced convection flow with passive and active techniques in a channel containing flow
separation and subsequent reconnection. The objective of the research was to give a synopsis of the effects
of several parameters, such as the Prandtl number, Reynolds number, nanoparticle volume fraction,
Hartmann number, tilt angle, buoyancy force, and Coriolis force. The objective of the research was to give a synopsis of the effects of several parameters, such as the Prandtl number, Reynolds number, nanoparticle volume fraction,
Hartmann number, tilt angle, buoyancy force, and Coriolis force.
Sarraa B. Younis; Dhuha A. Al-kazzaz
Abstract
The emergence and spread of digital technology in architectural design and professional practice has resulted in a restructuring of architectural education. Different approaches have emerged to integrate digital design into architectural curricula. This paper aims to identify accredited digital design ...
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The emergence and spread of digital technology in architectural design and professional practice has resulted in a restructuring of architectural education. Different approaches have emerged to integrate digital design into architectural curricula. This paper aims to identify accredited digital design courses and the nature of the content provided to enhance students’ knowledge and skills. The research problem revealed the diverse and different ways to integrate digital design into architectural education curricula in general, and there is no clear vision of the knowledge content of digital design courses. The research questions were determined to investigate the main aspects of digital design courses, the types of knowledge provided, and the levels of knowledge provision for these courses. To answer the questions, the study adopted a conceptual analysis of the published literature on university experiences in teaching digital design courses. The content of these courses was analyzed and revealed that the types of provided content ranges from preparing design projects at different scales, conducting exercises on implementing digital models, or presenting purely theoretical knowledge. The levels of implementing computer technology in teaching digital design range from representative, formative, generative, performative, and manufacturing levels. The relationships between traditional design education and digital design education are found in three ways: the digital design education replaces the traditional design education, the parallel application of both traditional and digital design paths or adopting digital design education later after traditional design education.
ALi sadoon mohmmad
Abstract
Fuels based on petroleum have been used for many years. However, as the world strives to protect the environment, clean and renewable energy is becoming more sought after. Diesel fuel can be replaced with biodiesel and alcohol. One of the advantages of these fuels is that they are renewable and locally ...
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Fuels based on petroleum have been used for many years. However, as the world strives to protect the environment, clean and renewable energy is becoming more sought after. Diesel fuel can be replaced with biodiesel and alcohol. One of the advantages of these fuels is that they are renewable and locally produced. This study prepared different fuel mixes using pure Iraqi diesel as a reference and an air-cooled, single-cylinder, compression-ignition diesel engine. In this study, an experimental investigation is conducted to introduce biofuel-heavy alcohol blends as alternatives to Iraqi high-sulfur diesel. In order to produce D80B20, diesel, and biodiesel made from used cooking oil were combined. Higher alcohols (hexanol and butanol) were also added to this mixture in a 10% ratio. The engine was operated at a speed of 2500 rpm and with various loads ranging from 4 kW to 10 kW to assess its exhaust emissions. In comparison to diesel, CO levels in exhaust emissions were reduced by 29.23%, 23.59%, and 13.85%, respectively, in the tested blends, while CO2 levels were raised by 23.26%, 16.86%, and8.56%, respectively. Reductions of 25.88%, 42.35%, and 11.76%, were observed in HC concentrations. D80B10HEX10 and D80B10BU10 showed reductions of 5.7% and 3.8% in NOx emissions, while an increase of 3.5% was observed using D80B20.
Fouz D Alqazweeny; Ali A. Jazie
Abstract
Hydrodeoxygenation (HDO) is a critical step in upgrading biomass-derived feed-stocks to renewable fuels and valuable chemicals. Thus, we preserve the environment through the use of agricultural waste. Water plays the role of solvent, reactant, or byproduct in biomass HDO reactions catalyzed by Co/HB ...
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Hydrodeoxygenation (HDO) is a critical step in upgrading biomass-derived feed-stocks to renewable fuels and valuable chemicals. Thus, we preserve the environment through the use of agricultural waste. Water plays the role of solvent, reactant, or byproduct in biomass HDO reactions catalyzed by Co/HB zeolite catalysts. The hydrodeoxygenation of linoleic acid was examined in this contribution in a patch-packed-bed reactor with a beta zeolite range of (5-15) mg catalyst at a temperature range of 230-300 K and throughout 2-3 h. Linoleic acid, an unsaturated fatty acid, was used in this work to create hydrocarbons in the diesel range, as well as to clarify the impacts of zeolite quantity, temperature, and time on the product yield to produce biofuels from Linoleic acid by hydrodeoxygenation in the high-pressure reactor in the presence of the catalyst, the products characterized by gas chromatography–mass spectrometry (GC-MS). Based on the results of optimization, it was determined that the hydrodeoxygenation reaction primarily eliminated the oxygen atoms from fatty acids. The yield of the intended products was 96.2% at the Co/HB zeolite amount (10% wt), high reaction temperature (270 ºC), and time (150 min) conditions.
qasim Abbas shammari
Abstract
Stoichiometric (NiTa) superalloys have lately acquired acceptability as an alternative to traditional current-generation alloys for applications requiring biomaterials. This is because to the high melting points and corrosion resistance of Ni and Ta. Nickel-based superalloys are highly prized in particular ...
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Stoichiometric (NiTa) superalloys have lately acquired acceptability as an alternative to traditional current-generation alloys for applications requiring biomaterials. This is because to the high melting points and corrosion resistance of Ni and Ta. Nickel-based superalloys are highly prized in particular technological applications due to their outstanding mechanical properties that need heat and corrosion resistance. They are utilized to resist applications at temperatures above 80% of their initial melting points more than any other family of technical alloys. Due to tantalum's high melting point and ability to store and release electric charges, high-tech industries are interested in it. During the COVID-19 pandemic lockdown, electronics have become a requirement of daily existence. Many materials still corrode and are not heat resistant, including those used in heat exchangers, steam boiler tubes, missile and airplane parts, turbine engine parts, and other elements. According to research, NiTa alloys perform better in terms of mechanical and tribological qualities than a number of typical alloys. Finally, this research is provided in order to assess how NiTa alloy has evolved. in order to increase the rigid dynamic structure's sensitivity to vibration.
maha kareem; Abbas Khalaf Mohammad
Abstract
PMMA (poly methyl methacrylate), a well-known polymer of the methacrylate family, is widely utilized in biomedicine, particularly in odonatological applications like artificial teeth, dentures and denture bases, obturators, provisional or permanent crowns, and so on. The outstanding qualities of PMMA, ...
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PMMA (poly methyl methacrylate), a well-known polymer of the methacrylate family, is widely utilized in biomedicine, particularly in odonatological applications like artificial teeth, dentures and denture bases, obturators, provisional or permanent crowns, and so on. The outstanding qualities of PMMA, such as its beauty, low density, and changeable mechanical properties, make it an ideal option for use in dentistry. The use of hybrid nanofillers comprising of zinc and zirconium oxides (ZrO2:ZnO) with PMMA and the investigation of the resulting changes in mechanical properties, compared to the addition of natural nano powder represented by nano bran (nB), was studied. The effect of introducing bran powder after turning it into a nanomaterial into PMMA and studying the change in mechanical characteristics was investigated. The use of these components lowers the cost of polymer formulations, allowing for the development of new biodegradable formulations and greatly lowering the environmental load on nature after using consumer items made from them. The bran powder material was added in different weight ratios (2%, 4%, 6%, 8%,10% and 12%), as well as ZrO2: ZnO as a hybrid nanofiller, which were added in the same proportions compared to the pure resin. An increase in the compressive strength was observed to reach its highest value at 206 Mpa of nB compared to the ZrO2:ZnO where it was 140 Mpa. As well as concerning flexibility, an increase in the elastic strength was observed where it was for ZrO2:ZnO and Bran respectively 68 Mpa and 88.98 Mpa compared to pure PMMA.
Fouad Jalal Mahmood
Abstract
Contemporary hospitals may be recognized by a large variety of activities, not only delivery of care but also some concerns, such as the satisfaction level of users. This research investigates the relationship between outpatient department (OPD) design elements and medical staff satisfaction and performance, ...
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Contemporary hospitals may be recognized by a large variety of activities, not only delivery of care but also some concerns, such as the satisfaction level of users. This research investigates the relationship between outpatient department (OPD) design elements and medical staff satisfaction and performance, especially in light of the pandemic since 2020. A mixed-method approach was used to gather doctors' and nurses' perspectives at two hospitals in Sulaimani City. This involved an EBD questionnaire and a modified AEDET checklist where respondents filled out a 39-item questionnaire at the hospitals' OPD. The results highlight the importance of the interior environment's quality in promoting the satisfaction of medical staff. The results from the medical staff surveys showed that most medical staff expressed satisfaction with the indoor design elements, and three factors, infection control, interior appearance, and comfort and control, were essential to creating a satisfactory indoor environment. A negative correlation of some demographic information, such as practical experience and educational attainment, with medical staff satisfaction was revealed. The findings suggest that investigating the views of the medical staff can indicate the level of significance of various elements that increase their satisfaction and performance, contribute to the general body of knowledge, and inform design decisions.
Kawa Abdulghany Abdullah; Ramzi Raphael Ibraheem Barwari
Abstract
Variable Refrigerant Flow (VRF) systems are extensively employed for space heating and cooling, particularly in multi-story buildings where outdoor units are discreetly placed behind aluminum louvers for architectural considerations. However, these metal louvers can hinder ventilation and heat rejection ...
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Variable Refrigerant Flow (VRF) systems are extensively employed for space heating and cooling, particularly in multi-story buildings where outdoor units are discreetly placed behind aluminum louvers for architectural considerations. However, these metal louvers can hinder ventilation and heat rejection of the VRF air-conditioning outdoor unit, adversely affecting system performance. This impact manifests in elevated suction temperatures, increased energy consumption, and a diminished coefficient of system performance due to hot air recirculation behind the louvers. Additionally, the expelled hot discharge air from outdoor units rises, increasing the suction air temperature for the upper floors' VRF system. This numerical analysis study investigates the impact of louver tilt angle and opening ratio factors on the thermal performance of VRF air conditioners when installed on building balconies. The objective is to optimize louver designs for concealing condensing units, thereby enhancing overall performance and minimizing power consumption. Two proposed louver designs, incorporating varying tilt angles and opening ratios, are presented as solutions and compared with the existing design. The optimal solution to alleviate the unintended "stuck and stack effects" in the current design involves a proposed modification. The first option suggests decreasing the louver's tilt angle to 20° while maintaining a 60% opening ratio to lower suction temperatures and improve thermal performance. Additionally, increasing the louver opening ratio to 80% effectively reduces air recirculation, providing an alternative solution to optimize the overall performance of the VRF system. Comparisons with previous studies underscore local climate variations and operational disparities, emphasizing the need for tailored louver designs specific to environmental conditions.
Tariq M. Salman; Maher K. Mahmood Al-Azawi; Viktar Tsviatkou
Abstract
Load balancing in internet services acts as a reverse proxy to distribute network bandwidth or application traffic across a number of servers. The decrease of internet route cost calculated from the distance, number of hops, bandwidth capacity, equipment maintenance, power consumption ...etc. is needed ...
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Load balancing in internet services acts as a reverse proxy to distribute network bandwidth or application traffic across a number of servers. The decrease of internet route cost calculated from the distance, number of hops, bandwidth capacity, equipment maintenance, power consumption ...etc. is needed to make the network intermediate devices more intelligent. The aim is to make the devices to be self-decision, acting upon data found in network and transport layer protocols (Internet Protocol IP. Transmission Control Protocol TCP, File Transfer Protocol FTP, User Datagram Protocol UDP), delivering the services to the secondary internet (wireless or optical fibers) ISPs. To achieve this target, the use of operation research algorithm, such as linear programming, has been proposed to solve the problem of minimizing transport and distribution cost by developing a technique to overcome the transmission load cost of the path selection. The proposed Efficient Weighted Round Robin Load Balancer EWRRLB will assign different costs to each internet connection based not just on its capacity or priority, but also will take into account the cost of transmission path. This allows load balancer to allocate the best economic path, beside larger share of the bandwidth to certain connections.
Turkan Ahmed Khaleel; Omar Anwer Nafea
Abstract
An emerging networking technique called fog computing extends cloud computing capabilities to the edge network's borders. It is employed to get around the limitations of cloud computing, like latency and bandwidth problems. Fog computing is suitable for IoT systems and applications that require ...
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An emerging networking technique called fog computing extends cloud computing capabilities to the edge network's borders. It is employed to get around the limitations of cloud computing, like latency and bandwidth problems. Fog computing is suitable for IoT systems and applications that require real-time processing, reliable network access, low latency, and strong security. In this work, the objective is to design and implement a fog computing environment to simulate the behavior of a multi-user healthcare application, which represents the monitoring of elderly care homes in Mosul city. Several algorithms were employed to examine the effects of load balancing inside fog computing networks. These algorithms are Random, Round-Robin, and the modified Throttled algorithm, which is modified by adding an extra management layer to be more suitable for fog computing networks. The response time results obtained from implementing this modified method were superior to those of the random algorithm and closely resembled the response time results of the round-robin algorithm. In case QoS1 with 25 clients, the result was (0.246037794) second without the load balancing algorithm, (0.124323358) second in the Random algorithm, (0.115641477) second in the Round-Robin algorithm, and (0.114981575) second for the modified throttled algorithm. thus, making it applicable for fog computing networks and cloud computing networks.
zaid sabah hamdi aldarib; Abeer Alkraway
Abstract
A bridge is one of the most important structures of man-made construction intended to enable passage across a gap, such as a river, valley, intersection, etc. The bridges can be provided for many purposes, such as facilitating water movement, individuals, vehicles, and railroads. The selection of the ...
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A bridge is one of the most important structures of man-made construction intended to enable passage across a gap, such as a river, valley, intersection, etc. The bridges can be provided for many purposes, such as facilitating water movement, individuals, vehicles, and railroads. The selection of the bridge's site should consider equity, effectiveness, efficiency, societal benefits, and economic ones. In structural engineering, prestressing methods are frequently used to improve structural components and systems' load-carrying capacity and serviceability. Increases in service loads or the end of a structure's useful life necessitate frequent maintenance and repair work. It is possible to reinforce and repair both steel and concrete buildings. The primary goal of this work is to provide a review of the literature on the assessment of prestressed concrete box girder bridges under static loads as well as investigate the strengthening methods employed by researchers to reinforce prestressed concrete box girder bridges.
Zainab Jabbar Shadhan; Salem Alhamd; Mohammed Nsaif Abbas
Abstract
Adsorption behavior can be determined using different essential studies which are adsorption isotherm, kinetics, and thermodynamics. In this study, adsorption isotherm models in addition to a kinetic and thermodynamics studies are used to describe the using of alumina, as an effectiveness adsorbent, ...
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Adsorption behavior can be determined using different essential studies which are adsorption isotherm, kinetics, and thermodynamics. In this study, adsorption isotherm models in addition to a kinetic and thermodynamics studies are used to describe the using of alumina, as an effectiveness adsorbent, for removing vanadium (V+5) ions from aqueous solutions contaminated by this metal. The aqueous solutions used were simulate the wastewater of most traditional oil refineries. This efficiency can be determined by comparing the correlation coefficients of the linear relationships used with each model. Using alumina, perfect removal of vanadium ions was achieved. Vanadium removal increases with increasing the operating conditions which are time, temperature, agitation speed, pH, and adsorbent’s media dose; however, it is increase with eliminating the initial concentration. The study shows that the vanadium’s adsorption based on Langmuir isotherm model gives correlation coefficient of 0.9999, while when it follows Temkin and Freundlich isotherms gives less correlation coefficient; hence adsorption on the surface of alumina takes place in monolayer surface with a regular distribution of particle’s binding energy and narrow quantity of identical sites on the adsorbent surface. On the other hand, kinetic study shows that the process of adsorption matches pseudo-second order kinetic model with R2=0.9999. Also, using the thermodynamics study approves that the adsorption is spontaneous endothermic process of enthalpy change.
Zuhal Ahadi Hamza; Ahmed Makki Al-Sulaiman; Hussein Ibrahim Abdel-Shafy
Abstract
Pollutants in water bodies pose a serious threat to both the aquatic ecosystem and human health. Ion exchange is used as a chemical process to remove unwanted dissolved ions from water and wastewater. It is widely accepted in developing countries. This analysis provides a bibliometric examination to ...
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Pollutants in water bodies pose a serious threat to both the aquatic ecosystem and human health. Ion exchange is used as a chemical process to remove unwanted dissolved ions from water and wastewater. It is widely accepted in developing countries. This analysis provides a bibliometric examination to consider the status and trends of advanced ion exchange worldwide. This study was conducted using the Dimensions website to identify and collect the most important research papers. The retrieved manuscripts were organized through Microsoft Excel and then VOS viewer was used to analyze the data by reviewing previous studies related to ion exchange as a contaminant removal treatment. To create maps and find out which countries, universities, and journals have published research articles on topics related to ion exchange, as well as authors who have studied the topic of ion exchange and their research, cooperation. To benefit from these studies and learn the importance of ion exchange as a treatment for removing pollutants. The electro neutrality of the ion exchange (IOEX) process must always be maintained because it is a stoichiometric process. Search results for IOEX were exported from Dimensions to a CSV file, both coexistence, cooperation with affiliate countries and consortia were implemented on the full search results. Ion exchange treatment has proven effective in treating industrial wastewater and domestic wastewater. Professionals and practitioners in the field are provided with important information through this examination of ion exchange research. The analysts learned about leading academic and research institutions, the state of the exploration field, and the most controversial issues surrounding advanced ion exchange. In addition, this lesson will provide the opportunity to learn basic facts that will develop the extent of ion exchange knowledge. The bibliometric survey method can also be used to visualize the trend of research and study in various fields.
Mohamed Qassim Kadhim; Hassan Falah Hassan
Abstract
The behavior of reinforced concrete (RC) members with glass fiber reinforced polymer (GFRP) bars has been the focus of several studies in previous years. However, a study to investigate the behavior of reactive powder concrete (RPC) columns reinforced with GFRP bars (GFRP-RPC) has not been conducted. ...
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The behavior of reinforced concrete (RC) members with glass fiber reinforced polymer (GFRP) bars has been the focus of several studies in previous years. However, a study to investigate the behavior of reactive powder concrete (RPC) columns reinforced with GFRP bars (GFRP-RPC) has not been conducted. This study aimed to study the structural behavior of circular columns fully reinforced with GFRP bars and hoops or spirals. In the present study, the behavior of GFRP-RPC circular columns under axial load is studied with the effect of four variables: longitudinal reinforcement ratio, transverse reinforcement ratio, transverse reinforcement configuration (hoops vs. spirals), and type of longitudinal reinforcement (GFRP, steel, and hybrid). Twenty circular columns with a diameter of 150 mm and a height of 1000 mm were cast and tested, divided into seven groups. Results discuss failure modes, axial load capacity, deformations (displacement and strains), and ductility. Test results indicate that the load capacity of the columns increased by ranging from approximately 46 to 56.25% when the longitudinal reinforcement ratio increased from 1.77 to 3.55%, also increased the transverse reinforcement ratio from 1.24 to 2.48% enhanced the load capacity ranging from approximately 5.13 to 19.1%. Moreover, the nominal capacity of GFRP-RPC columns was compared with the design equations so, the results were verified.
Mohammed Abd Al-salam Majeed; Salah M. Salih
Abstract
A steady-state effect analysis of enhancing the cooling performance of a photovoltaic/thermal (PV/T) collector using a damper that changes the flow direction with the multi-flow channel is investigated numerically and experimentally. The study aims to improve the electrical efficiency of PV/T systems ...
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A steady-state effect analysis of enhancing the cooling performance of a photovoltaic/thermal (PV/T) collector using a damper that changes the flow direction with the multi-flow channel is investigated numerically and experimentally. The study aims to improve the electrical efficiency of PV/T systems with turbulent generation to increase exchange between absorbent panels and airflow with less pressure drop. The effect of different mass flux rates (MFR) of (0.04, 0.05, 0.06, 0.07, and 0.08) kg/s, and various solar flux of (600, 800, and 1000)W/m^2 on solar cell (PV) temperature and PV/T system performance is studied under indoor test conditions. The results indicated that the air temperature is inversely proportional to the air MFR, and the overall efficiency highly depends on the air MFR and solar flux intensity. In addition, the experiment result shows that the higher value at air MFR (0.04-0.08)kg/s, solar flux (1000 W/m^2) for electrical, thermal, and overall efficiency are (17.03%, 74.14%, and 90.4%), respectively. Moreover, The percentage output power its (28.44%) by (15.93) W leads to pioneering results compared to previous studies
Saif M. Abbas; Ayad M. Takhakh; Jumaa S. Chiad; Borhen Louhichi
Abstract
Introduction: Osseointegration are a particular kind of prosthesis that is inserted a short titanium rod or screw into the bone surgically and joined to the prosthetic limb.Experimental part: This study looked at a patient's gait analysis with above-knee amputation wearing osseointegration prosthesis ...
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Introduction: Osseointegration are a particular kind of prosthesis that is inserted a short titanium rod or screw into the bone surgically and joined to the prosthetic limb.Experimental part: This study looked at a patient's gait analysis with above-knee amputation wearing osseointegration prosthesis implant when walking above force plate. Evaluated the mechanical and fatigue properties of a Ti13Nb13Zr alloy implant.Theoretical part: Drawing and analysis a femoral bone model with an osseointegration implant using Ansys Workbench 17.2.Results and discussion: The results of the tensile testing showed an ultimate tensile strength of 553 MPa, average yield strength of 480 MPa, an elongation of 19.66%, and a Young's modulus of 2.73 GPa. Furthermore, a compressive strength of 1010 MPa and compression yield strength of 700 MPa were found by compression testing. The results of fatigue testing, which were displayed as S-N curves, highlighted the alloy's time-dependent fatigue behavior by showing decreasing fatigue strength with an increase in cycles. Force plate showed amaximum force of 600 N was reported. A strong safety margin was shown by Finite Element Analysis in the bone containing the implant, with safety factors often more than 5 and low deformation (2.4 mm) appropriate for prosthetic uses. A good static design was confirmed by the Von-Mises stress distribution, which was primarily below 46 MPa.Conclusion: Comprehensive results confirm the mechanical feasibility of the Ti13Nb13Zr alloy for prosthetic applications and offer important new information for improving prosthetic design, guaranteeing durability, and improving safety in practical applications.
Fadhil Toufick Aula
Abstract
Electric storage systems like solar systems and electric vehicles use batteries for storing electricity due to their simplicity, efficiency, considerably small size, and dispatchability. These batteries operate on the principle of charging/discharging and require equalization for voltage balance, especially ...
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Electric storage systems like solar systems and electric vehicles use batteries for storing electricity due to their simplicity, efficiency, considerably small size, and dispatchability. These batteries operate on the principle of charging/discharging and require equalization for voltage balance, especially in series-connected batteries. In this research, a novel technique is presented for enhancing batteries’ voltage equalization, which is based on the variable duty cycle, D, of pulse width modulation (PWM) in the dynamic capacitor technique. This method controls two energy storage elements: an inductor and a dynamic capacitor via variable D of PWM. The presented technique was implemented on lead-acid batteries connected in series using MATLAB/Simulink. The simulation results showed that increasing D to 80% can reduce the equalizing process time from 500 seconds to just 125 seconds, with voltage differences decreasing from 800mV to just 2.2mV, equalized by 99.98%. For comparison, a well-known fixed switched-capacitor technique was used, and results showed that variation of D had no effect even after 500 seconds of the equalizing process, and the batteries’ terminal difference voltages still were above 220mV (less than 72% equalizing). Thus, the presented technique demonstrates superior performance, highlighting the significant contribution of variable duty cycle PWM in balancing batteries’ terminal voltages.
Rana A. Yousif; Sady A. Tayh; Abbas F. Jasim; Sarah F. Khalaf
Abstract
Incorporating crumbed rubber into asphalt binder or asphalt concrete mixes has become increasingly common in recent years. Researchers have looked into how well this additive can improve both the modified bitumen and the modified asphalt mix. With the growing usage of rubber crumb modifiers in asphalt ...
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Incorporating crumbed rubber into asphalt binder or asphalt concrete mixes has become increasingly common in recent years. Researchers have looked into how well this additive can improve both the modified bitumen and the modified asphalt mix. With the growing usage of rubber crumb modifiers in asphalt mixtures, the significance of certain asphalt qualities has been recognized. This has opened up more opportunities for a thorough examination of their rheological and physical properties. The asphalt-rubber binder's performance was often impacted by the amount of crumb rubber and the blending circumstances. In this study, a new method, the Steam Aging Technique (SAT), was utilized to study the attributes of the rubber-enhanced bitumen, which was aged throughout Bitumen’s service. The primary goal of this research was to investigate the influence of traditional aging methods compared to the steam aging method, and the possibility of using the latter as an alternative test to traditional methods. Overall, physical test results showed notable increases in softening point and rotational viscosity and a decrease in penetration value for vapor-aged bitumen contrasted to non-aged bitumen. This research used a dynamic shear rheometer (DSR) and a temperature sweep test (TS) method to study rutting under control strain mode. The effectiveness of the use of steam aging has been observed and the possibility of using it as an alternative to the conventional aging methods available was investigated. It was found that there was a great convergence in the results extracted from the steam aging device with an addition rate of 5, 10, and 15% and an aging time of 45 minutes with the results extracted from the rotary kiln device, except for the 20% addition rate, which gave a difference in values.
Murtadha Ali Nsaif
Abstract
Visible light communication (VLC) has gained traction for high-speed wireless connectivity leveraging LED lighting elements. Orthogonal Frequency Division Multiplexing (OFDM) is an attractive modulation scheme owing to its spectral efficiency and resilience to multipath distortion. However, the nonlinear ...
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Visible light communication (VLC) has gained traction for high-speed wireless connectivity leveraging LED lighting elements. Orthogonal Frequency Division Multiplexing (OFDM) is an attractive modulation scheme owing to its spectral efficiency and resilience to multipath distortion. However, the nonlinear electro-optic transfer characteristics of optical components introduces signal clipping and quantization noise which corrupts OFDM signals. This paper provides an in-depth analysis of clipping and quantization noise to quantify the impact of LED nonlinearities on OFDM-based VLC system performance. Detailed mathematical models are derived for clipping distortions owing to LED optical power saturation and quantization errors from ADC/DAC finite precision in the modulator and driver circuitry. We quantify through simulations the degradations in terms of error vector magnitude (EVM), signal-to-noise ratio (SNR) loss, and bit error rate (BER) under varying clipping ratios and quantization bit-depths. We demonstrate based on 16-QAM OFDM transmission that the LED driver should possess at least 12 dB signal linear dynamic range and 3 bits quantization to restrict SNR penalty within 3 dB. Adaptive tone mapping and digital pre-distortion techniques are discussed to compensate for intensity distortions enabling high-speed OFDM transmission over VLC links.
