Vibration Monitoring of the Gradual Worn in Journal Bearings
Conference paper

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Osama Amhammeed Altaher Hassin, (08-2020), Huddersfield, UK: COMADEM, 1-5

A Comprehensive Methodology for Evaluating Conversation-Based Interfaces to Relational Databases (C-BIRDs).
Conference paper

Evaluation can be defined as a process of determining the significance of a research output. This is usually done by devising a well-structured study on this output using one or more evaluation measures in which a careful inspection is performed. This paper presents a review of evaluation techniques for Conversational Agents (CAs) and Natural Language Interfaces to Databases (NLIDBs). It then introduces the developed customized evaluation methodology for Conversation-Based Interface to Relational Databases (C-BIRDs). The evaluation methodology created has been divided into two groups of measures. The first is based on quantitative measures, including two measures: task success and dialogue length. The second group is based on a number of qualitative measures, including: prototype ease of use, naturalness of system responses, positive/negative emotion, appearance, text on screen, organization of information, and error message clarity. Then an elaboration is carried out on the devised methodology by adding a discussion and recommendations on the sample size, the experimental setup and the scaling in order to provide a comprehensive evaluation methodology for C-BIRDs. In conclusion the evaluation methodology created is better way for identifying the strengths and weaknesses of C-BIRDs in comparison to the usage of single measure evaluations.

Fathi Sidig Mohamed Gasir, (08-2020), Intelligent systems and applications: Intelligent systems and applications, 196-208

Bimetallic Mo–Fe Co-Catalyst-Based Nano-Carbon Impregnated on PAC for Optimum Super-Hydrophobicity
Journal Article

The application of super-hydrophobic nanomaterials for synthesizing membranes with unique physiochemical properties has gained a lot of interest among researchers. The presence of super-hydrophobic materials inside the membrane matrix can play a vital role not only in the separation of toxins, but also to achieve higher water flux with lower fouling tendencies required for an efficient membrane distillation process. In this research, super-hydrophobic carbon nanomaterials (CNMs) were synthesized using powder activated carbon (PAC) as a precursor, whereby the growth was initiated using a bimetallic catalyst of iron (Fe) and molybdenum (Mo). Until recently, no research has been conducted for synthesis and to observe the catalytic influence of bimetallic catalysts on the physiochemical characteristics of the derived CNMs. The synthesis process was carried out using the chemical vapor deposition (CVD) process. The CVD process was optimized using Box–Behnken factorial design (BBD), whereby 15 experiments were carried out under different conditions. Three input variables, which were percentage composition of catalysts (percentage of Fe and Mo) and reaction time (tr), were optimized with respect to their impact on the desired percentage output of yield (CY) and contact angle (CA). Analysis of variance (ANOVA) testing was carried out. It was observed that the developed model was statistically significant. The highest CY (320%) and CA (172°) were obtained at the optimal loading of 5% Fe and 2% Mo, with a reaction time of 40 min. Surface morphological features were observed using field emission scanning electron microscopic …

Fawzi Mohamed Amin Mohamed Elfagaih, (07-2020), Symmetry: MDPI, 8 (12), 1208-1242

Numerical Study of Four Bolts End-Plate Joint Behaviour for Robustness Assessment
Journal Article

The paper presents new studies on numerical modeling (FEM) for beam-to-column behavior under sagging and hogging bending moment when the framework is exposed to service and unexpected loads that may cause a column loss scenario. This investigation is focused on four bolts end-plate joints with 10 mm thickness which are proven experimentally to have more ductile behavior than other end-plates joints (6, 8 bolts), spite of their weakness to transfer the unexpected loads from the initial state to a residual state of the stable equilibrium, that leads to a failure of limited floor area to adjacent joints when tested experimentally (Saleh, 2014). FEM technique used in this research is an extension of the previous technique and is characterized by the use of a more sophisticated technique than the previous, discovered from the result of continuous research and the use of all the options available in the new version of commercial ABAQUS/CAD software. The elements are designed using multiple layers of specific elements of a brick arranged in such a way that the mesh nodes of the tiles should coincide with certain layers with the top of the shear inlay and in line with reinforcement, not as the former study that used thick shell elements to model the reinforced concrete slab with total negligence of reinforcing steel and bolts between the slap and the beam. This investigation is very complex because of highly nonlinear effects associated with the prediction of joint performance, such as structural imperfections, huge displacements and large rotations, inelastic properties of steel and concrete, bonding effects between steel and concrete, friction between …

Bashir Ali Kalifa Saleh, (02-2020), https://qspace.qu.edu.qa/bitstream/handle/10576/14718/CIC2020_%20Artcile125.pdf?sequence=1&isAllowed=y: Qatar University, 1 (1), 1-4

Acicular Ferrite Transformation by Isothermal Decomposition in Medium Carbon Vanadium Micro Alloyed Steel
Journal Article

The aim of the present paper is focused on nucleation onset and development morphologies of acicular ferrite and to evaluate microstructure and mechanical properties during isothermal austenite transformation in titanium free micro-alloyed steel. Isothermal treatment was carried out in the temperature range 350 to 450 C. These treatments were interrupted at different times between 2 and 1800 s in order to analyze the evolution of the microstructure. Yield stress was determined by compression testing on samples with final Microstructure. The metallographic evaluation was done by using optical and scanning electron microscopy (SEM) enabled determination of the nucleation onset at all treatments and subsequent on the development of acicular ferrite of isothermally treated titanium free micro-alloyed steel. The results show that during continuous cooling, dominantly acicular ferrite microstructure is formed. Main characteristics of acicular ferrite are intragranular nucleation and strongly disorganized microstructure with a larger ability to deflect cracks. Acicular ferrite is, therefore, widely recognized to be a desirable microstructure due to good mechanical properties.

Abdulnaser Hamza Ahmed Fadel, (12-2019), Al academia journal for Basic and Applied Sciences: Libyan Academy, 1 (2), 1-8

A systematic approach to evaluating the influence of demand side management resources on the interarea capacity benefit margi
Journal Article

Available transfer capability is an index to measure the security and economic viability of an interconnected system. However, to accurately determine this index, other associated parameters need to be accurately evaluated. One of these parameters is the capacity benefit margin (CBM). For efficient power generation reliability and sustainability, a certain amount of supply capacity is commonly reserved by utilities, which in most cases remain unused, to reduce the effect of generation outage. To minimize this unused reserve, utilities usually reserve a predetermined amount of tie-line capacity between interconnected areas to have access to external supply. This tie-line reserved for this purpose is termed as capacity benefit margin (CBM). In this paper a technique for computing CBM is used, the sensitivity of CBM support from other areas to the increase in load in one of the areas is investigated, and conclusively, demand side management is proposed to improve the quantification of CBM. The contribution of this work is the assessment of the CBMs support from other areas during a critical condition, using the flexibility of DSM technique. The modified 24-bus IEEE reliability test system is employed for the verification of the approach.

Olatunji Obalowu Mohammed, Mohd Wazir Mustafa, Daw Saleh Sasi Mohammed, Sani Salisu, Nabila Ahmad Rufa’i, (12-2019), Bulletin of Electrical Engineering and Informatics: Institute of Advanced Engineering and Science (IAES), 8 (4), 1-10

Resonance Identification of a Journal Bearing based on Frequency Response Function and Numerical Analysis
Conference paper

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Osama Amhammeed Altaher Hassin, (08-2019), Tripoli, Libya: ICTS (MI5032) International Conference on Technology, 1-4

CFD predictions of Swirl burner aerodynamics with variable outlet configurations
Conference paper



ABSTRACT

Swirl stabilised combustion is one of the most widely used techniques for flame stabilisation in gas turbine combustors. Lean premixed combustion systems allow the reduction of NOx coupled with fair flame stability. The swirl mechanism produces an aerodynamic region known as central recirculation zone (CRZ) providing a low velocity region where the flame speed matches the flow velocity, thus anchoring the flame whilst serving to recycle heat and active chemical species to the root of the f

ormer. Another beneficial feature of the CRZ is the enhancement of the mixing in and around this region. However, the mixing and stabilisation processes inside of this zone have shown to be extremely complex. The level of swirl, burner outlet configuration and combustor expansion are very important variables that define the features of the CRZ.

Therefore, in this paper swirling flame dynamics are investigated using computational fluid dynamics (CFD) with commercial software (ANSYS). A new generic swirl burner operated under lean-premixed conditions was modelled. A variety of nozzles were analysed using several gaseous blends at a constant power output. The investigation was based on recognising the size and strength of the central recirculation zones. The dimensions and turbulence of the Central Recirculation Zone were measured and correlated to previous experiments. The results show how the strength and size of the recirculation zone are highly influenced by the blend and infer that it is governed by both the shear layer surrounding the Central Recirculation Zones (CRZ) and the gas composition

HESHAM BAEJ, (07-2019), Engineering, Physics International Journal of Energy Technology: WEENTech, 31-43

Post Weld Heat Treatment Qualification of Type 304L Stainless Steel Weld Metal
Conference paper


. The aim of the present paper is focused on post weld heat treatment qualification by

describes the results of an investigation to understand the micro structural changes that taken place in type 304L stainless steel weld deposits as function of temperature / time by showing any presence of re-crystallization and / or strain induced grain boundary migration and the dissolution of any carbide formed at grain boundaries in welding monitored by metallographic examination.

Abdulnaser Hamza Ahmed Fadel, (03-2019), Libya: International Conference on Technical Sciences, 1131-1134

Available transfer capability calculation methods: A comprehensive review
Journal Article

The ceaseless efforts by power system industries to promote sustainable and competitive electric power market structure in the deregulated environment have given rise to enormous research in the area of transfer capability of transmission networks. Due to high demand for electricity, transmission components are stressed to operate close to their operating limits, and this leads to a decrease in transmission efficiency. To address this issue, efficient evaluation of available transfer capability (ATC) is crucial for system planning, operation, and control. Several approaches have been proposed for ATC computation. Surprisingly, a comprehensive literature review on ATC computation is yet to be efficiently presented. Researchers have been able to come up with fast algorithms, but most of these algorithms are not accurate, and the presented accurate techniques are not fast enough for online applications. This paper presents a comprehensive review of the different approaches for ATC determination. It provides the concepts, methods, and the features of the ATC. For each technique, the state of the art of the several contributions made by researchers has been highlighted. This review reveals that there are issues regarding ATC calculation methods that need attention: the development of fast and accurate algorithm incorporating system dynamics and system uncertainties in ATC determination. Additionally, efforts on the incorporation of renewable energy generation in the ATC evaluation need to be intensified. This review will serve as one in all for researchers as well as a guide for the entrants in this field.

Olatunji Obalowu Mohammed, Mohd Wazir Mustafa, Daw Saleh Sasi Mohammed, Abdulrahaman Okino Otuoze, (02-2019), International Transactions on Electrical Energy Systems: Wiley, 1 (1), 1-24