Mitigating Resonant Vibration via Compressor Base Frame redesign at Souq Al-Khamis Cement Factory, Libya (Part II)
Journal ArticleResonance occurs when the operating frequency of a system aligns with its natural frequency, resulting in amplified vibration amplitudes. To prevent potential damage and ensure optimal performance of a compressor's base frame at Souq Al-Khamis Cement Factory, researchers found the resonance in has been occurred when both the natural frequencies and rotating frequency were overlapped. Resonant Vibration in the base frames arises when the rotating vibration frequency aligns with the frame’s natural modes that leads to structural instability, fault unplanned shutdowns and production losses. This study analyzes resonant vibration in a cement factory compressor base frame and proposes a redesign using finite element methods to mitigate this issue. Four distinct modifications were made to the base frame on its shape, weight and boundary conditions: the first introduces fixed points to enhance rigidity, the second adds supports for increased stability, the third incorporates elements to improve durability, and the fourth enhances the thickness of the compressor. The results indicate that the redesigned configuration most effectively mitigates resonance and improves the system's natural frequency response.
Osama Amhammeed Altaher Hassin, Mostafa H Essuri Abobaker, (05-2025), Academy journal for Basic and Applied Sciences (AJBAS): الأكاديمية الليبية, 7 (1), 1-5
Comprehensive Analytical Study of Structural Reclamation in Aging Flexible Pavement
Journal ArticleThe progressive deterioration of flexible pavements, driven by increasing traffic loads, environmental influences, and material aging, necessitates the implementation of effective structural reclamation strategies to restore functional performance and extend service life. This study focuses on a critical segment of the Libyan coastal road network, specifically the 27.5 km part from Tripoli Street Bridge to Al-Krarim Gate. An analytical and quantitative investigation is undertaken to evaluate the structural condition and rehabilitation potential of the existing flexible pavement system, with particular attention to distress mechanisms, material degradation, and the effectiveness of various rehabilitation techniques. The assessment integrates field investigations, laboratory testing, based on AASHTO 1993, and to evaluate pavement distress, base soil strength, and asphalt concrete layers performance; Pavement Condition Index (PCI) values and core sample analyses are employed to determine the extent of structural failure. Visual distress surveys supplement the data to provide a comprehensive understanding of surface and sub-surface conditions. Analytical modeling, based on layered elastic theory is used to simulate pavement response under rehabilitated conditions and forecast long-term performance under loading. The study examines several rehabilitation methods, including full-depth reclamation (FDR), cold in-place recycling (CIR), and mechanical stabilization using cementitious additives. Each method is evaluated based on structural capacity enhancement, cost-efficiency, and service life extension. Results demonstrate that the selection of reclamation techniques tailored to subgrade conditions and traffic loads significantly improves structural performance and minimizes maintenance needs. The study concludes that full-depth repaving offers the most sustainable and economically viable solution for restoring the targeted roadway section.
Mohamed Ali Milad karm Salem, Abdalla Ali Agwila, Abdelbaset M. Traplsi, (05-2025), Journal of Alasmarya University: Applied Sciences: Journal of Alasmarya University: Applied Sciences, 2 (10), 118-134
Analytic Modeling to Study the Insolation Heat Gain of Semi Insulated Building in Hot Climate
Journal ArticleCountries located in temperate, hot and arid climates, such as Libya, face the critical need to cool houses whose internal temperatures rise due to these climatic conditions. This can be achieved by employing proper insulation techniques to prevent heat gain from solar radiation (insolation). This paper addresses the impact of not implementing thermal insulation for the roof of a building, in contrast to other external parts of the structure. The temperature distribution in a single-story building was studied using finite element analysis (FEA), along with how the building absorbs heat from its surroundings during a sunny day. The thermal analysis was conducted on a 3D concrete building with walls made of concrete masonry blocks, a floor height of 3.20 meters, and a total area of 40 square meters, using ANSYS 2020 R2 software. The building model includes thermal insulation for the external envelope, but the roof and openings remain uninsulated (as is often the case with home insulation practices in Libya). The finite element method is widely used due to its high effectiveness in simulation and achieving accurate results. The analysis results demonstrated the heat distribution gained from insolation, as well as variations in the rates of heat transfer from the building's exterior to its interior. The findings showed that neglecting the thermal insulation of the roof and window openings leads to an approximate 70% increase in the building's internal temperature. Furthermore, the results clearly indicated that insulating the building's walls alone is insufficient to prevent overheating. This provides a sufficient understanding of the prioritization required in applying insulation layers for buildings located in hot climates.
Mohamed Ali Milad karm Salem, (05-2025), Academy journal for Basic and Applied Sciences (AJBAS): Academy journal for Basic and Applied Sciences (AJBAS), 1 (7), 1-5
A study to Improve the Rigidity of Beam-to-Column Connections in Reinforced Concrete Frames for Residential Buildings
Journal ArticleAbstract:
The construction of residential buildings in the state of Libya has become increasingly expensive, necessitating cost-effective design solutions. Structural engineers play a critical role in reducing construction costs while ensuring safety and efficiency. One approach to achieving an optimal design is minimizing the dimensions of structural elements ,a critical factor influencing structural performance and economy is the rigidity of beam-to-column connections, which significantly affects deformations and then internal forces. According to beam bending theory, bending moments and shear forces are directly proportional to deformation. Therefore, reducing primary curvature leads to a decrease in design moments, allowing for more economical structural sections. This study investigates the impact of considering partial rigidity in beam-to-column connections within reinforced concrete (RC) frame, particularly for single-story buildings. In conventional structural design, connections are often assumed to be either fully rigid or fully pinned, neglecting partial rigidity effects. This oversimplified modeling approach results in overdesign and increased material consumption, deviating from sustainability principles. The research use SAP2000 structural analysis software to assess various degrees of connection rigidity and their influence on member deformation. The findings indicate that incorporating realistic connection rigidity can reduce beam deformation by up to 20% (at 0.7 rigidity) , leading to smaller and more cost-effective frame sections. Furthermore, common construction methods in the state of Libya inherently provide a certain degree of rigidity at beam-to-column interfaces, yet current design practices often overlook this advantage. This study underscores the importance of optimizing beam-to-column connection rigidety to enhance structural performance, reduce material usage, and align with sustainable design principles. The findings contribute to improving cost efficiency in RC frame construction, providing valuable insights for engineers seeking to optimize structural design in residential buildings
Keywords:Beam-to-Column,Connection, Sustainability, Optimum Design , Rigidety
Mohamed Ali Milad karm Salem, (03-2025), International Science and Technology Journal: International Science and Technology Journal, 36 (1), 1-13
Saving utility costs optimization in generator operation planning based on scalable alternatives of probabilistic demand-side management
Journal ArticleThe electric power system network has become more self-sufficient and less dependent on fossil fuel-based units due to the increasing integration of renewable energy resources. It is crucial to have an efficient method or technology for managing the system’s economics, security, reliability, environmental damage, and the un- certainties that come with fluctuating loads. In this context, this paper utilizes a framework based on probabi- listic simulation of a demand-side management approach and computational intelligence to calculate the optimal value of saving utility cost (SUC). Unlike traditional methods that dispatch peak-clipped resource blocks sequentially, a modified artificial bee colony (MABC) algorithm is employed. The SUC is then reported through a sequential valley-filling procedure. Consequently, the SUC is derived from the overall profitability of the gen- eration system and includes savings in energy costs, capacity costs, and expected cycle costs. Further investi- gation to obtain the optimal value of SUC was conducted by comparing the SUC determined directly and indirectly, explicitly referring to the peak clipping energy of thermal units (PCETU). The comparisons utilized the MABC algorithm and a standard artificial bee colony, and the results were verified using the modified IEEE RTS- 79 with varying peak load demands. The findings illustrate that the proposed method demonstrated robustness in determining the global optimal values of SUC increments, achieving increases of 7.26 % for 2850 MW and 5 % for 3000 MW, compared to indirect estimation based on PCETU. Moreover, SUC increments of 18.13 % and 25.47 % were also achieved over the conventional method.
Daw Saleh Sasi Mohammed, Muhammad Murtadha Othman, Olatunji Obalowu Mohammed, Masoud Ahmadipour, Mohammad Lutfi Othman, (03-2025), Sustainable Energy Technologies and Assessments: Elsevier, 75 (32767), 1-11
Systematic Approach for Fault Analysis and Power System Protection based on Wavelet Applications
Journal ArticleAbstract—In the current landscape of power system utilities, ensuring stability and reliability is more crucial than ever, highlighting the importance of your expertise and contributions. Protecting transmission lines is essential for maintaining these key attributes in power delivery. This study introduces an innovative approach using wavelet transform (WT) to an effective wavelet transform (WT) approach. Detect and classify transmission line faults. The unique capabilities of wavelets make them ideal for addressing transient disturbances in power systems. Our algorithm utilizes the discrete wavelet transform (DWT) to extract the three-phase current signal in the case of a single line-to-ground fault. Carefully selecting the Daubechies4 mother wavelet significantly enhances our ability to gather helpful information about fault conditions. The classification process is based on careful calculation. The absolute sum of the signal details at level 2 over a single cycle window provides precise insights. We employed Power System Computer-Aided Design / Electromagnetic Transients with DC (PSCAD/EMTDC) to generate the three-phase current signal in a tested 230 kv transmission system. The simulation results robustly demonstrate that our proposed algorithm excels in detecting and classifying both faulted and healthy phases, ensuring a future of heightened reliability in power systems.
Abdulhamid A. Abohagar, Daw Saleh Sasi Mohammed, (12-2024), Libyan Journal of Engineering Science and Technology: جامعة النجم الساطع, 4 (3), 1-5
Design of Intelligent Chatbot for Stress Management
Conference paperABSTRACT: This paper focuses on using natural language processing (NLP) in chatbots to manage stress in war-affected countries. A Java-based chatbot was designed to alleviate stress using two algorithms: TextRank and Stanford_CoreNLP. The problem was solved by integrating different languages using a plugin. The chatbot was tested with fifteen people and received positive feedback. Modifications were made based on user feedback, with journaling being a winner. However, the chatbot faced limitations like a lack of Arabic language support and voice chat features.
Adel Ali Faraj Eluheshi, Amira Shlebik, (12-2024), Libya: The International Journal of Engineering & Information Technology (IJEIT), 17-27
Simulation of Vertical Waterflooding In a Hawaz Reservoir Using Eclipse for Reservoir Pressure Maintenance
Conference paperWater injection has proven to be one of the most successful, efficient and cost-effective reservoir management strategies. By reinjecting treated and filtered water into tanks, this approach can help maintain tank pressure, increase hydrocarbon production, and reduce environmental impact. The goal of this project is to create a water injection model using Eclipse tank simulation software to better understand water injection methods to maintain tank pressure. A basic reservoir model is utilized in this investigation. The simulation was performed about 52 years using ECLIPSE Reservoir simulator. In all cases, result shows that oil production with water injection is higher compared with the base case. With this, it would be preferred to apply waterflooding for oil recovery in depleted reservoirs to the use of primary methods. It is also observed that water breakthrough is earlier and water production increases gently with water injection rates. Sensitivity on the injection rate using the 3D model showed that the injection rate has impact on the process. The pressure increases with high injection water rate in all cases. Despite higher reservoir pressure and early in water breakthrough, water flooding accounts for less oil recovery due to rapid water production. Generally, based on the results and discussions, it can be concluded that the water injection option can be used to increase the reservoir pressure to a good extent.
Madi Abdullah Naser Abdullrahman, (11-2024), Sebha University Conference Proceedings: مجلة جامعة سبها للعلوم البحثة و التطبيقية, 367-374
دوروأهمية نظم المعلومات الجغر افية في مجال النقل البري (ورقة استعراضية
مقال في مؤتمر علميتعتبر الطرق من أهم المنشآت في حياتنا والتي نعتمد عليها اعتماد كلي في نقل البضائع والمواصلات, وهي وسيلة النقل الأساسية داخل وخارج المدن لهذا يجب أن تكون هذه الطرق امنة وسليمة وخالية من المشاكل والعيوب, لذلك يجب متابعة مواعيد صيانتها وتطويرها والتخطيط الدائم لان تكون هذه الطرق ضمن المشاريع والخطط الدائمة للتنمية والتطوير, حتى توفر نظام نقل جيد يساعد على الازدهار والتقدم داخل الدول. وبعد ثبوت أهمية نظم المعلومات الجغرافية ودخولها وسيطرتها في اغلب المجالات عامة وفي مجال الطرق خاصة ومساعدتها على حل المشكلات وتحليل البيانات وتسهيل وتوفير الوقت والجهد في ترتيب وحفظ البيانات ايضا وقدرتها على حفظ كمية ضخمة من البيانات بطريقة منظمة ومنسقة, تبحث هذه الدراسة في الأبحاث السابقة حول دور نظم المعلومات الجغرافية ( )GISفي هندسة الطرق، بهدف فهم أهمية هذه التكنولوجيا واستخدامها الفعال في هذا المجال. تسعى الدراسة إلى تجميع الأفكار من خلال مراجعة مجموعة من الدراسات السابقة ها لتوضيح أهمية نظم المعلومات الجغرافية ودورها النشط في تطوير شبكات الطرق وتحسينها وتصميم وتخطيطها
آلاء الرحمن علي الفتلاوي، اسماعيل قودان علي نايل، (11-2024)، المؤتمر السابع للعلوم والتكنولوجيا: مجلة جامعة سبها للعلوم البحثة و التطبيقية، 456-468
Analytic Study of Linear Analysis vs. Nonlinear Analysis: Optimum and Sustainable Structure Perspective
Journal ArticleAbstract::
This paper presents a comprehensive analysis of linear and nonlinear structural analysis methods, evaluating their Its effect in optimizing and sustaining structural designs. By leveraging advanced scientific data and analytical techniques, this study aims to discern the optimal conditions and scenarios for employing each method. The research includes detailed calculations, comparative data, and case studies, emphasizing the sustainability implications and long-term benefits of each approach.
Mohamed Ali karim, (11-2024), مجلة جامعة سبها: مجلة جامعة سبها للعلوم البحثة و التطبيقية, 3 (3), 23-24