Natural Sciences

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A COMPARISON OF NUMERICAL SOLUTIONS FOR ONE FREDHOLM INTEGRAL EQUATIONS SYSTEM OF THE SECOND KIND
(An-Najah National University, 2025-02-06) Badrien, Mohammed
The main goal of this work is to propose various numerical techniques for approximating the solution of a system of Fredholm integral equations of the second kind. The methods proposed involve the Chebyshev collocation method, the Haar wavelet method and the reconstruction of the variational iteration method. After reviewing the basic concepts of Fredholm integral equations and addressing the mathematical framework of these numerical methods, we provide some illustrative numerical examples with known exact solution to illustrate the effectiveness and the efficiency of these methods. Numerical results show clearly that Chebyshev collocation method is one of the most efficient method for solving system of Fredholm integral equations in comparison with its counterparts.
A PROPOSED METHOD FOR MITIGATION THE UNBALANCED CURRENTS IN POWER DISTRIBUTION NETWORK WITH PV SYSTEMS
(An-Najah National University, 2025-04-23) Raed Aref Kmail, Ahmad
This study aims to solve the problem of uneven electricity use in homes that share a three-phase power supply. This unevenness happens when too many houses rely heavily on just one or two of the three power lines, leading to wasted power, overloaded lines, voltage drops and even blackouts. The growing use of solar panels on homes makes this problem even worse since the amount of electricity they produce can fluctuate . To fix this, the project created a smart system that uses a microcontroller and WiFi technology to constantly monitor and adjust how electricity is distributed among the three power lines. It keeps track of how much power each house uses and how much solar energy is being produced, then automatically shifts houses between the lines to keep things balanced. Tests of this system show losses reduced from 138 kW to 9 kW—resulting in cost savings of $193.2, or $3.75 per house. The system achieved a simple payback period of less than one month. Furthermore, the lowest network voltage improved from 206 V under unbalanced conditions to 221 V after implementing the balancing solution. This study is important because it shows how to better manage modern power grids that include a lot of solar energy. By using this system, power companies can ensure a more stable and dependable electricity supply to homes while also supporting the use of renewable energy sources like solar power.
ACCEPTANCE AND SATISFACTION WITH ELECTRONIC HEALTH INFORMATION SYSTEM BY HEALTHCARE PROVIDERS IN PALESTINIAN HOSPITALS
(An-Najah National University, 2024-08-22) Sabri Dweikat, Ahmad
Background: This study investigated the factors influencing employees’ acceptance and satisfaction of Electronic Health Information Systems (EHIS) in An-Najah National University Hospital and Rafidia Surgical Hospital. Methods: The study included healthcare workers, including physicians, nurses, medical secretaries, pharmacists, laboratory technicians, and radiologists. The study investigated fifteen hypotheses related to relative advantage, system quality, top management support, information technology (IT) department support, and competitive pressure. Results: A total of (n = 220) The research study, found no significant gender differences in EHIS acceptance (55% males, 45% females). Educational backgrounds varied, with 71% holding bachelor's degrees, 22% master degrees, and 7% diplomas. Participants with younger ages and less experience exhibited different perspectives on EHIS. Postgraduate participants showed greater awareness of relative advantage. The study also revealed that external factors such as relative advantage, system quality, top management support, and competitive pressure significantly affected perceived usefulness (PU) and ease of use (PEOU). Conclusion: The study looked at factors affected the acceptance of EHIS by Palestinian hospital staff and found that perceived usefulness (PU) was highly impacted by system quality, relative advantage, competitive pressure, top management support, and IT department support, while organizational support, compatibility, and system complexity had little effect on perceived ease of use (PEOU).
ADAPTIVE LEARNING USING ARTIFICIAL INTELLIGENCE: AN INNOVATIVE APPROACH FOR E-LEARNING PLATFORMS
(An-Najah National University, 2025-06-03) Khalil , Bashar
E-learning has become an important area of scientific research, especially since the COVID-19 pandemic, which has led to increased focus on this topic. However, many e-learning systems still use a one-size-fits-all approach, similar to trying to fit a single shirt size on all men's sizes. To address this issue and accommodate individual differences among students, an adaptive learning system is needed. This system can provide tailored learning paths that match each student's academic level and personal needs. This research introduces an adaptive learning system called Najah-AI. In this system, the curriculum is divided into specific learning objectives, and various recommendation systems are used, including collaborative and content-based approaches. The nearest neighbor machine learning algorithm was chosen for its suitability to the data type in this study. The findings revealed that 71% of students benefited from the adaptive e-learning system, and their performance improved significantly after watching videos that supported the learning objective where they were struggling.
ALGAE FOR NUTRIENTS REMOVAL FROM WASTEWATER: THE APPLICATION OF ARTIFICIAL LIGHT FOR ENHANCED ALGAL GROWTH
(An-Najah National University, 2024-10-10) Alhamaydeh, Ahlam
Treating municipal wastewater using algae to remove nutrients is considered one of the most successful, environmentally friendly, and inexpensive natural methods, as algae grow naturally in wastewater if the appropriate conditions are available for its growth, such as nutrients, temperature, duration, and intensity of exposure to light, as well as the presence of bacteria that form a symbiotic relationship with algae to help it grow. This research studied the effect of artificial light on the growth of algae and its activity in removing nutrients from municipal wastewater. Three beakers of municipal wastewater in which the algae grew, with a volume of 5 liters as a pilot scale of patch reactors, were used and placed in the same conditions which were Temperatures and mixing for 15 days, with varying durations of exposure to artificial light. In the first sample, the algae was exposed to light 24 hours a day and was called the light sample. The second beaker was exposed to light for 19 hours, the fifth was exposed to natural daylight and was called half light sample, and the third sample remained in the day and night cycle, where it was called the natural sample. After 15 days of comparing the three samples, although the results were close in the two light and half-light samples, the algae in the light sample were the most efficient in removing nutrients from wastewater, as their efficiency in removing COD was 95% and phosphorus was 96%. 99.8% ammonium, TSS concentration 737.4 mg/L, and chlorophyll A pigment concentration of 129.4 μg/L. In the half-light sample, the effectiveness of algae in removing COD was 93%, phosphorus was 94%, ammonium was 99.8%, TSS concentration was 237.4 mg/L, and chlorophyll A concentration was 57.2 μg/L. Finally, in the natural sample, the efficiency in removing COD was 93%, phosphorus was 6%, ammonium was 56%, TSS concentration was 174 mg/L, and chlorophyll A concentration was 8 μg/L. These results show the effectiveness of algae as a natural method for removing nutrients from wastewater and the positive effect of light on improving algae growth and its efficiency in the treatment process.
AN AHP BASED CRITERIA FOR ASSESSING AI ASSISTED DESIGNS AS PERCEIVED BY DESIGNERS
(An-Najah National University, 2025-02-13) Kayed, Aseel
This thesis presents the development of an Analytical Hierarchy Process (AHP) framework to assess artificial intelligence (AI)-assisted architectural designs. The main objective is to construct a priority scale that reflects the experts' evaluation of the relative importance of different design elements. To this end, after an extensive systematic literature, four primary standards—authenticity, beauty, inventiveness, and harmony—were found to be crucial for judging architectural designs. Sub-criteria were derived from each of these primary criteria to offer a more detailed assessment. A panel of professionals in the domains of architecture and artificial intelligence were administered a two-part questionnaire in order to inform the suggested framework. The participants' backgrounds and prior exposure to AI were gathered in the first section of the questionnaire. In the second section, the specified criteria and sub-criteria were evaluated. Thirty responses were collected and analyzed. The AHP results show that, inventiveness with 35.5% weight is the most influential factor for assessing AI-assisted designs. Authenticity with a weight of 21.5% and harmony with a weight of 24% are, respectively, the next two most important criteria. Beauty was found to have a weight of 19%. The most important sub-criterion for authenticity with their weights were found to be design consistency (36.1%), with material integrity (20.4%), authentic expression (22.7%), and historical context (20.8%). The top ranking factors for beauty are integration with the environment (43.7%), visual impact (22.1%), timelessness (20%), and detailing (14.2%). Emerged as the highest-ranking element of inventiveness is sustainable solutions (36.1%), with technical innovation (23.1%) and adaptive reuse (23.9%) also having significant effects. A smaller but still significant impact is made by spatial novelty (16.9%). Material coherence (28.3%), spatial harmony (21.2%), and proportionate balance (16.3%), environmental synchronization (34.2%) are the main components of harmony. The study's findings led to the development of a solid and organized framework for assessing architectural projects helped by artificial intelligence. The contribution of this research is mainly for researchers, architects, and stakeholders to be able to quantitatively assess architectural designs that are produced by AI with a novel AHP based approach evaluation method. This framework contributes to the ongoing discourse about the incorporation of Artificial intelligence in the field of architectural engineering, more specific the architectural design by prioritizing important design elements and providing a systematic method for upcoming evaluations. A thorough assessment of design quality is made possible by the framework's methodical approach, which highlights the significance of coherence, contextual integration, and sustainability.
ANALYSIS AND IMPROVEMENT OF NEDCO ELECTRICITY DISTRIBUTION NETWORK OF JENIN GOVERNORATE AND CLARIFYING THE IMPACT OF SOLAR PHOTOVOLTAIC PENETRATION
(2022) Haitham Alawneh
This thesis starts by getting information from North Electrical Distribution Company (NEDCO) about all parameters and contents of the electrical network of Jenin, such as transmission lines, underground cables, transformers, loads, and PV systems in detail with all lengths, diameters, capacities, average annual consumption and PV systems power. ETAB simulator program was used to build this network, and the analysis started at a low voltage side at every load. Thesis focus on the power quality and voltage quality through the analysis. The objective of this thesis is to improve the power and voltage quality of the whole network in different ways, such as improving power factor to be more than 95% with respect to IEEE standards, improving low voltages at some loads and reducing drop voltages to be within 5% as IEEE standards, and reducing power losses using techniques such as: adding new PV systems, adding new capacitor banks, increasing the tap changers. Depending on the readings of the voltage bus and power factor (i.e., real and reactive power) of each load bus. Also, this thesis discusses another subject: the PV penetration level. It describes in detail the problem led by high penetration in the network and loads. It also discusses the solution to each problem. High PV penetration in the network causes many problems such as power losses, voltage rise, voltage fluctuations, voltage unbalance and reverse power flow that impacts the power quality; also, it causes a negative on power factor, voltage sag, harmonics, and frequency. The thesis suggests many solutions for these problems, such as: using an on load tap changer, reactive power control, energy storage system, PV generation curtailment, and smart inverter, and passive filters to reduce the harmonics effect. These solutions are described in detail in chapter 4. However, these solutions aim to balance real power and reactive power production to improve the power factor, avoid reverse power flow, store the power and use it at a suitable time and reduce harmonics effect to be within 5% for THD and less than 3% for IHD as IEEE standards. Keywords: Effect of high PV Penetration; Improve power quality; Improve voltage quality; Improvement of NEDCO; Harmonics Effect.
ASSESSING CLIMATE CHANGE VULNERABILITIES OF THE SOLID WASTE MANAGEMENT IN PALESTINE -RISK MANAGEMENT APPROCH
(2024-02-18) Jafar Talib Ismail
Abstract Climate change threatens solid waste management in vast ways in Palestine by augmenting environmental risks as well as matters of public health. Thus, this thesis covering the interactions of climate vulnerabilities (temperature, rainfall, extreme weather, sea level and winds( within the regional wastes management practices and aimed at developing strategies towards climate resilience. The goal is to help people cope better with climate change on waste management by providing policymakers with sound advice. The thesis aims to build a holistic approach that guarantees waste disposal practices conform to global norms and contribute to a greener environment by considering climate change vulnerability and waste management. The research included quantitative assessment for historical data (rainfall, evaporation, temperature) and analysis it using R studio software (R programming for integrated development environment to analysis historical data and visualization), then applied to perform ARCGIS 10.8 mapping of the data levels to analyze areas with high climatic changes. This thesis also used qualitative assessments such as interviews with policy makers to determine which vulnerabilities are the most severe and which strategies work best for climate change vulnerabilities. According to experts in ministry of local government said the national strategy play a significant role in the mitigation of climate change and ensuring sustainable demands coordinated efforts in the development of waste management sector in Palestine. The key results showed that some regions like Gaza and south of Palestine has certain challenges and more vulnerable with regard to climate change. According to results the extreme weather such as storms, floods and draughts are high, rainfall and temperature are moderate, winds and rising sea level are low. The main strategies to be included are (Recycling programs, waste to energy, public awareness, sustainable procurement practices, circular economy, extend producer responsibility, climate resilience infrastructure). In addition to installing methane pipes in Zahrat Al-Finjan, expanding recycling programs for paper, cartons and plastic, reinforcing trash container such as strong frame to prevent movement during high winds and covering it to make transportation more efficient. Keywords: Climate Change, Mapping, Vulnerability, Waste Management, Palestine, Strategies.
ASSESSING THE IMPACT OF ADOPTING GREEN INNOVATION PRACTICES ON SUSTAINABLE PERFORMANCE IN PALESTINIAN CONSTRUCTION INDUSTRY: GREEN ORGANIZATIONAL CULTURE AS A MODERATOR
(An-Najah National University, 2025-06-17) Faour, Maryana
The construction industry is considered one of the largest contributors to environmental degradation; therefore, most scholars are recently seeking to integrate green practices within this industry to achieve a sustainable future. Accordingly, this study includes five main objectives, including investigating the impact of adopting green innovation (GI) practices on sustainable performance in its three pillars (i.e., environmental, social, and economic) in the Palestinian construction industry, in addition to exploring the moderating effect of green organizational culture (GOC) on this relationship. Moreover, it assesses the level to which Palestinian construction firms are willing to adopt and implement GI practices, as well as the level of GOC and sustainable performance. For this purpose, a quantitative research approach using a self-administered questionnaire was adopted. The target population of the study consists of key practitioners in the Palestinian construction industry, i.e., contracting, consulting, and engineering firms, in which specific classifications were identified for these firms to be included in the sampling frame. Thus, 143 valid responses were obtained, one response from each firm, and the SmartPLS software was used to analyze the study model and test the proposed hypotheses. The findings show that the level of adopting GI practices and sustainable performance in Palestinian construction firms is high, whereas GOC is being implemented at a moderate level. Besides, the findings indicate a positive and significant relationship between the adoption of GI practices and sustainable performance. Further, GOC positively impacts both adopting GI practices and sustainable performance and also positively moderates the relationship between them. Undoubtedly, examining the effect of GI on sustainable performance with the presence of GOC in such a unique and complicated context offers a set of significant implications. In detail, the study contributes to GI theory by emphasizing the importance and effectiveness of adopting GI practices in conflict-affected and resource-constrained contexts, as well as to the GOC theory by confirming its ability to facilitate the adoption of GI practices and achieve sustainable performance. The study fosters policymakers and stakeholders in the construction industry to transform conventional construction activities into green ones by adopting GI practices, thereby enhancing sustainable performance. Ultimately, this study bridges the gap regarding the misconception of GI and its impact on sustainable performance in the construction industry, especially in a developing country such as Palestine, which suffers from a complex context of political instability, ongoing conflict, and limited resources. Based on the available literature, this is the first study that explores the moderating role of GOC between the adoption of GI practices and sustainable performance in the Palestinian construction industry.
ASSESSMENT OF WIND ENERGY POTENTIAL IN PALESTINIAN TERRITORIES
(An-Najah National University, 2024-06-24) Qasem Solaiman, Motasem
The Occupied Palestinian Territories (OPT) face significant challenges due to a high dependency on imported conventional energy sources, including petroleum and approximately 90% of its electrical energy needs from Israeli companies. This dependency results in elevated energy costs and susceptibility to price fluctuations. Amidst these challenges, The energy dilemma has a vital solution in renewable energy. with wind energy representing an underutilized yet promising resource within the OPT. Despite its global significance, wind energy's potential remains largely untapped in the OPT due to a limited number of studies, professional capacity constraints, and geopolitical barriers, alongside the high costs associated with wind energy technologies. These factors have led to a palpable sense of frustration and the perception of wind energy projects as impractical within the region. This study uses exacting scientific procedures to thoroughly examine and evaluate the possibility of wind energy in the OPT. Employing the Weibull distribution method, The goal of the study is to present a thorough summary of the state of wind resource evaluations as of right now., explore existing wind energy conversion technologies suitable for the OPT, and present detailed wind characteristics for specific regions under study. Additionally, it aims to identify the most viable locations for wind turbine installations and determine the most appropriate turbine types for these areas. Through this approach, the research endeavors to offer substantive insights and recommendations to overcome the challenges facing wind energy implementation in the OPT.
ASSOCIATION BETWEEN BLOOD MAGNESIUM LEVEL AND COGNITIVE IMPAIRMENT AMONG COMMUNITY DWELLING OLDER ADULTS IN TULKARM: A CROSS-SECTIONAL STUDY
(An-Najah National University, 2024-05-09) Layan Alkum
Background: The investigation into the potential association between blood Magnesium level and cognitive impairment among community dwelling older adult in Tulkarm stems from a growing interest in understanding modifiable factors influencing cognitive health in aging populations, magnesium deficiency is associated with poor cognition or dementia. Objectives: The purpose of this study is to determine the prevalence of Magnesium deficiency, to determine the association between magnesium levels in the blood and to determine the factor that associated with magnesium deficiency among community dwelling older adult in Tukaram. Methodology: A cross-sectional design study was conducted among 200 participants aged 60 years or older. The participants were selected by convenient sampling from Tulkarm Governance. The collected data included: sociodemographic characteristics, medical history, life style, nutritional status, cognitive status and functional status. Mini Nutrition Assessment (MNA) tool was used to screen for malnutrition while Mediterranean Diet Adherence Screener (MEDAS) was used to determine the adherence to Mediterranean diet. Magnesium deficiency was defined according to Magnesium levels less than (1.9 mg/dl). Cognitive function was assessed using the Montreal Cognitive Assessment (MOCA) test. Functional status was determined using activity of daily living (ADL) and instrumental activity of daily living (IADL). SPSS21 software was used to analyze the data, and Chi Square test was used to determine the association between magnesium level and other variables. Results: The finding revealed that 63.5% were female, with a mean age of 64.6±3.3 years old. Most of the participants (72.5%) were married, 67.5% did not receive formal education, and 40.5% were not working. The most prevalent chronic diseases were: hypertension (32.5%), diabetes (29.0%), and heart disease (15.0%). In terms of lifestyle, 19.0% smoked and 77.5% good sleep quality. A low magnesium level was discovered in 30.5% of the population. The mean cognitive and functional status were; (24.5±3.66), ADL (5.4±1.19), IADL (6.2±3.2) respectively. The results revealed that, there was a significant association between magnesium levels and smoking status (P=0.006), IADL (P=0.048), and cognitive function (P=0.011). There were no significant relationships detected with sociodemographic, sleep quality, Physical Activity, body mass index, malnutrition or adherence to Mediterranean diet. Conclusions: The prevalence of magnesium deficiency was 30.5%, it was significantly associated with smoking status, IADL and cognitive performance. These findings shed light on the association between magnesium deficiency and numerous elements of participants' lives, as well as possible links to lifestyle and health concerns, Recommendation: The study findings suggest prioritizing the dietary consumption of older persons and raising awareness about the need of selecting nutrient-rich foods that are high in minerals and vitamins, particularly magnesium. Additional investigation is advised to ascertain the efficacy of Magnesium supplementation on the cognitive and functional condition of elderly individuals. It is advisable to conduct a longitudinal research to examine the causal factors that affected magnesium intake which may impact the cognitive and functional status of older adults in the Palestinian community. Keywords: aging population, magnesium deficiency, cognitive function, functional status
BIOBASED IMIDAZOLE DERIVATIVES WITH VERSATILE BIOACTIVITIES
(2024-03-07) Saber Mahmoud Abu-Jabal
Abstract Imidazole is known to be a highly momentous biomolecule since it is demonstrated to possess exceptional biological properties, like antimicrobial, antifungal, inhibition of nitric oxide synthase, and cytotoxic activities. Vanillin was used as the starting material in this study, it is a natural phenolic substance, and it makes up the majority of the vanilla orchid's bean and pod. It is used as a flavoring agent and as a preservative in the pharmaceutical industry and cosmetics. This work aims to synthesize a novel natural vanillin-based imidazolone derivatives and zwitterionic vanillin-based imidazolone derivatives with alkyl sulfonate moiety starting from the natural product vanillin. Thirty new derivatives were synthesized. Various spectroscopic methods analyzed all prepared derivatives. The anticancer properties of all derivatives were evaluated against two liver cancer cell lines (Hep-3B, LX2) and cervical cancer (HeLa). Moreover, the molecular docking between some of the prepared compounds and DNA was performed. The study discovered that a few of these substances have high impact on preventing the growth of two types of cancer cells liver cancer (Hep-3B) and cervical cancer (HeLa), and compounds with the numbers (3, 4, 5, 7, 8, 9, 11, 13, 14, 17, 24, 26) shown extraordinary efficiency against these cancer cells with low viability against the normal cells. A molecular docking study showed excellent interaction of some of these derivatives with the DNA through forming strong H-bonding. Prepared compounds with the alkyl sulfonate moieties showed improvement in the anticancer efficiency. In conclusion, a new novel set of imidazoles and synthesis of imidazolone with alkyl sulfonate moiety were successfully prepared. The anticancer activities were very promising, which makes the synthesized compounds possible future drugs for the treatment of various cancers. Keywords: Hippuric acid; oxazolone; imidazolones; anticancer; Benzimidazole; Schiff.
BIOLOGICAL ACTIVITY OF PLANT EXTRACTS FROM MIDDLE EAST AREA ON FOOD BORNE PATHOGENS
(2018-07-24) Nouraldin Shtaya
ABSTRACT there's many research investigate of high activity of plants extract and microbes and during the past few decades there has been a notable increase in the demand natural preservatives. The aim of our study to evaluate six methanolic extracts of medicinal plants from Palestine against 18 bacterial indicator strains (gram positive & gram negative). Six methanolic extracts were prepared from different parts of plants used in traditional medicine in Palestine. We prepared the crude extract by using methanol and distilled water, and used rotary evaporator, Testing by using two method paper disc diffusion and agar well diffusion. In our study has shown the antibacterial activity for all methanolic extract of plants we tested Origanum syriacum L. Var. syriacum, Rhus coriaria L., Rumex acetosa L, Salvia hierosolymitana Boiss, Teucrium capitatum L, Cyclamen persicum mill at different amount range (5µL-50 µL ). In addition the results we got it, can be first step for various future research.
COMPUTATIONAL METHODS FOR SOLVING VOLTERRA INTEGRO-DIFFERENTIAL EQUATIONS
(2022-10-20) Masa Husam Saeed Desuqi
Background: Integro-Differential Equations (IDEs), one of the most important mathematical tools in both pure and applied mathematics, arise in many physical problems such as wind ripple in the desert, nano-hydrodynamics, population growth model, glass-forming process.. They have motivated a huge amount of research in recent years. Many researchers have developed numerical schemes for solving these IDEs. Aim: In this work, the researcher proposed three numerical schemes, namely, the Taylor collocation method, Legendre polynomials method and the Haar wavelets method, to approximate the solution of Volterra Integro-Differential Equations (VIDEs). Material and method: These three numerical methods have been applied in the form of algorithms, and Maple software has been developed/used to solve some numerical examples. Results: The numerical results showed that the convergence and accuracy of the aforementioned methods were in good agreement with the analytical solution. Comparison of numerical results, mentioned in tables and figures, showed clearly that the Haar wavelets method provides more accurate results and is, therefore, more effective than other methods. Keywords: Volterra integro-differential equations; Taylor collocation; Legendre polynomials; Haar wavelets. Introduction Importance of Integral Equations: the subject of IDEs have attracted the attention of many scientists and researchers over the past few years due to their wide range of applications like wind ripple, hydro-dynamics, glass-formation, model of population growth and various models in physics, engineering and medicine, namely the mathematical modelling of epidemics, particular when the models contains age-structure or describe spatial epidemics [5, 6]. Literature Review Many numerical schemes for solving VIDEs have been constructed and implemented by many researches. For example, Karamete et al. [19] used collocation method based on Taylor expansion to solve VIDEs. Khater et al. [20] implemented the Legendre polynomials method to approximate the solution of VIDEs subject to initial conditions. Ali [2] has applied the Haar wavelets approach to obtain an approximate solution to VIDEs. Draidi et al. [12] used the product Nystrom in parallel with the sinc-collocation scheme to solve integral equations with Carleman kernel. Hamaydi et al. [16] solved fuzzy integral equations using variational iteration and Taylor expansion techniques. Moreover, Fazeli et al. [14] suggested several numerical schemes to approximate the solution of VIDEs. Other numerical techniques for solving VIDEs are: variational iteration [30], Walsh expansion series [26], Chebyshev collocation [1], Nystr"o" ̈m method [22], differential transform [11], homotopy [25], power series [3] and finite difference [10]. Burton [7, 8] has investigated in the 1980s some stability results for the VIDEs. Zhang [31] has also presented some stability results for VIDEs. Tunc [28] and Staffans [27] proposed a new stability results based on Lyapunov functional for VIDEs. In this work, we suggest three numerical techniques to solve VIDEs, namely, Taylor collocation method, Legendre polynomials and Haar wavelets method. The VIDE under consideration has the form: Y^((n) ) (x)=r(x)+∫_a^x▒F(x,t)Y(t)dt where Y^((n) ) (x)=(d^n Y)/(dx^n ) ,n∈N subject to the initial conditions: Y^((s))=a_s , s=0,1,2,…,(n-1). The kernel F(x,t) and the function r(x) are given. The unknown function Y(x) is to be determined. A major objective is to compare between these numerical techniques in approximating the solution of the VIDE by solving some numerical examples. We organize this work as follows: chapter one deals with some general aspects of VIDEs together with their solvability. In chapter two, we address all the aforementioned methods, namely, Taylor collocation, Legendre polynomials and Haar wavelets methods. We conclude chapter three by solving some VIDEs with known exact solution by the aforementioned algorithms.
CuO FILMS PREPARED BY COMBINED ELECTROCHEMICAL AND CHEMICAL BATH DEPOSITIONS
(2022-06-16) Sondos Waleed "Mohammad Ali" Omareyyeh
Abstract Background: Thin film electrodes are emerging in solar energy technology to produce electricity from light. CuO is one example of common semiconductors that did not yield high photoelectrochemical (PEC) performance. This is a problem to solve. Objectives: The present study aims at producing CuO thin film electrodes with high PEC performance. CuO thin films will be deposited onto FTO/glass substrate by electro-chemical deposition (ECD), chemical bath deposition (CBD) and combined EC/CB deposition techniques. The resulting electrodes will be assessed in photoelectrochemical process, after being modified by annealing and by cooling rate control (fast and slow cooling). Methodology: Three techniques have been used to deposit CuO thin film on fluorine doped tin oxide (FTO) Glass substrate. These techniques are; chemical-bath deposition (CBD), electrochemical deposition (ECD) and combined electrochemical and chemical bath (ECD/CBD) deposition technique. The prepared films were characterized by various methods including; X-ray diffraction (XRD), scanning-electron microscope (SEM), electronic absorption spectra and photoelectrochemical measurements. Effect of annealing temperature, cooling rate and deposition time have also been studied. The CuO films exhibit p-type conductivity as shown by photoelectrochemical characteristics (PEC) study. Results: The prepared films exhibit low photoelectrochemical behaviors. Higher PEC characteristics were gotten from CBD method, but they need annealing at temperatures higher than 150 ̊C in order to remove the resulting Cu(OH)2. Annealing at high temperatures affect CuO films negatively, since CuO has a very small band gap (1.3-2.1 eV). Combined ECD/CBD technique does not improve CuO thin film characteristics which against our predictions. The prepared films show good stability measurements. Conclusions: The prepared films exhibit low photoelectrochemical behaviors. CBD method is the best method to prepare CuO films with higher PEC characteristics, but needs annealing to remove resulting Cu(OH)2. Because the CuO has very small band gap, it is sensitive to annealing at high temperature. Higher temperatures affect the films negatively. On the other hand, ECD method gives CuO films with more uniform structures with no Cu(OH)2 product, but do not have improved PEC characteristics. Films deposited by combined ECD/CBD did not show improved PEC characteristics. Annealing ECD/CBD films negatively affects their SEM micrographs, due to sensitivity of the ECD layer to annealing. Suggestions: CuO thin films can be prepared with more modifications, e.g: coating with multiwalled carbon nano tubes (MWCNT) is recommended. More annealing temperatures should be studied to optimize film characteristics. Electrochemical deposition may be repeated several times to enhance film performance. Doping the prepared CuO films with other dopants is recommended. Depositing combined EC/CB CuO thin film on other type of substrates. For example, Indium tin oxide (ITO) substrate. Keywords: Thin films, chemical bath deposition (CBD), electrochemical deposition (ECD), combined EC/CB deposition, annealing.
DECISION TREE TO CLASSIFY JETS OF PARTICLES IN HIGH-ENERGY PHYSICS
(An-Najah National University, 2025-04-10) Khaled, Marwa
This study investigates the application of Decision Tree and Random Forest models to tackle the challenge of jet classification in particle physics, focusing on categorizing jets into five key particle types: light quarks (q), gluons (g), W and Z bosons, and top quarks. Using a dataset from Zenodo comprising list of 53 High-Level Features derived from jet events, we explored Decision Tree and Random Forest models within the machine learning framework to enhance classification accuracy. Our approach involved building and comparing various Decision Tree and Random Forest models, assessing configurations such as tree depth, the minimum number of samples leaf, and the number of trees in the Random Forest ensemble to optimize performance. In our jet classification research, the Random Forest model outperforms the Decision Tree model in classifying particle physics events, achieving higher precision, recall, F1-scores, and an overall accuracy of (85.32%) compared to (81.32%). Optimal Random Forest performance was obtained using 100 trees, maximum depth = 10, and top 20 selected features, which also reduced training time by 36.8%. In contrast, the best Decision Tree configuration used maximum depth = 8 and maximum features = 40. This research highlights the potential of Random Forest to achieve high jet classification accuracy and offers insights into optimizing Random Forest models for similar tasks in particle physics research.
DEGRADATION OF PHARMACEUTICAL CONTAMINANTS IN WATER USING NANO-PLATINUM BASED ELECTROCATALYST
(An-Najah National University, 2024-10-23) Nassar, Ibrahim
Recently, the presence of contaminants, such as pharmaceutical compounds in effluents and groundwater, has increased. Pharmaceutical compounds impose significant risk to water, which makes the search for radical solutions to treat water necessary. This research studied the degradation of the contaminant phenazopyridine (PhP), as low concentrations of it may affect water quality. Electrodes have been prepared, to completely mineralize this contaminant, by two deposition methods. The Pt-E/FTO electrodes were prepared using electro-deposition of platinum nanoparticles (from H2PtCl6 solutions) on FTO. The Pt-T/FTO electrode was prepared by spraying H2PtCl6 solution on FTO, followed by heating at 350 °C. Other electrodes were prepared by deposition of Pt onto multiwalled carbon nanotubes (MWCNTs) pre-deposited onto FTO electrodes. Both electrodeposition and spray deposition were examined to prepare Pt-E/MWCNTs/FTO and Pt-T/MWCNTs/FTO electrodes, respectively. EDS, XPS, XRD SEM and AFM analyzed all resulting electrodes. The electrodes were then examined in electrooxidation of PhP in a three electrode-cell, containing PhP aqueous solution (40 ppm, 70 mL). The experiments were made on PhP solutions under different conditions in several parameters. Among the various electrodes, it was found that Pt-E/MWCNTs/FTO electrode was the best electrode, in terms of electrodegradation efficiency and stability. In PhP solution (40 ppm) about 68.38% was removed within 120 min at 25 °C with no added electrolyte at initial pH ≈ (3.0) using +1.60 V (vs. SCE). This electrode was then singled out in more study to see the effects of various reaction parameters. Reaction kinetics showed that the oxidation-reaction was pseudo-first order with respect to PhP and the measured reaction order was 0.69. That is due to the presence of an adsorption factor that affects the reaction kinetics. When the reaction was carried out for 5 h, complete mineralization of PhP was observed, leaving no organic contaminants remaining in solution, as confirmed by total-organic carbon (TOC), resulting nitrate ion analysis, high-performance liquid chromatography (HPLC), and electronic absorption spectra. A plausible mechanism for the electrooxidation reaction, to explain the results, was proposed based on earlier literature. The developed Pt-E/MWCNTs/FTO electrode showed high reusability to electro-degrade PhP. The results showed the high potential of the electrode to treat pharmaceutical contaminants in water through the electrooxidation process. The results indicated the future potential of the electrode in commercial scale water purification processes.
DESIGN, SYNTHESIS, BIOACTIVITY AND MOLECULAR DOCKING OF IMIDAZOLONE DERIVATIVES HAVING HYDROPHILIC AND LIPOPHILIC FUNCTIONALITIES
(An-Najah National University, 2025-05-07) Fares, Oswa Marwan
The currently used chemotherapies showed negative side effects that can lead to permanent damage to human organs. Therefore, finding an effective anticancer therapy with minimum side effects is considered a major challenge for scientists. In this work, two new series of imidazolones were prepared, one containing phenyl group (3a-g) and the other containing thiophene group (5a-g). Both of these imidazolones were combined with different substituents including lipophilic and hydrophilic moieties. The synthesis was performed via condensation cyclization of vanillin-based oxazolones with various amines. The anticancer activity of the synthesized imidazolones was analyzed against four different cancer cell lines: liver cancer cells (HepG2), cervical adenocarcinoma cells (HeLa), colon cancer cells (CaCo-2) and breast cancer cells (MCF-7). Among the prepared imidazolones, it was found that imidazolone 3f with dodecyl chain exhibited the highest anticancer activity with IC50 value of 65.26 ± 3.2 µM against HepG2 and 20.02 ± 3.5 µM against MCF-7. Imidazolone 3d with amino alkyl group displayed an IC50 value of 36.57 ± 4.1 µM against the Hela cell and 24.68 ± 3.8 µM against the CaCo-2 cell line. Imidazolone 5g with thiophene and pyridyl group showed the highest efficiency among all tested derivatives with an IC50 value of 18.44 ± 2.3 µM and 5.96 ± 2.3 µM against Hela and CaCo-2 cell lines, respectively. Imidazolone 5b with chlorophenyl moiety displayed an IC50 value of 2.18 ± 0.7 µM and 5.51 ± 1.1 µM against HepG2 and Hela cell lines, respectively. Computational tools were also used to evaluate the pharmacokinetics, and the antitumor potential of imidazolone molecules with the highest activities through ADME analysis and molecular docking. ADME properties, estimated by the Swiss ADME server, emphasize favorable drug-likeness under Lipinski’s guidelines, with molecular weights ranging from 357.43 (5d) to 468.65 g/mol (5f). Molecules 3g, 3f, and 5f show optimal hydrogen bonding, moderate bioavailability (0.55), and synthetic accessibility scores from 3.78 to 4.76. Docking studies with proteins 4MAN and 1HNJ highlight strong interactions for 3g, 3f, and 5f, with molecule 3g showing the best binding for 4MAN (-52.13 kcal/mol) and 5f for 1HNJ (-38.63 kcal/mol). These results recognize 3g and 5f imidazolones as promising candidates for targeted cancer therapy. In addition, antibacterial activity was studied for the prepared oxazolones. It was noticed that oxazolone 8 containing 2-thiophenyl moiety was the most potent to stop the bacterial growth of all types of bacteria, even the most resistant Staphylococcus aureus with MIC of 500 µg/mL. A combination of these oxazolones with commercial antibiotics can provide a synergetic effect to inhibit the bacterial growth at lower MIC values.
DETECTION OF HOT SPOTS IN HETEROGENEOUS SOLAR PV PANELS USING DIFFERENT MACHINE LEARNING ALGORITHMS
(An-Najah National University, 2024-07-04) Odeh, Sabri
Localized overheating, also known as hot spotting, can occur in specific areas of a solar panel where excessive heat is generated within photovoltaic (PV) systems. This problem may occur as a result of uneven distribution of current, inconsistencies in shading, issues with soldering, or failures in the packaging, leading to a condition of reverse bias and localized heating. The presence of hot spots not only accelerates the degradation of PV systems but also increases the risk of permanent damage to the panels. Therefore, it is crucial to promptly identify and rectify any hot spot faults to ensure the safe and reliable operation of the PV system. This study investigates the utilization of six distinct machine learning classifiers (SVM, KNN, DT, ANN, XGBoost, CatBoost) for the identification and categorization six cases (healthy, one hotspot, two hotspot series, two hotspots parallel, three hotspot series and more, and three hotspots parallel and more) of early hotspots in PV modules. The data collection was done by real measuring instruments such as: current and voltage sensors, also environmental sensors for irradiance and temperature. Before the implementation of the machine learning tool, the data of each examined PV module was applied by preprocessing data methods such as: cleaning, deleting outliers, and transforming raw data into a format suitable for training and evaluating machine learning models. These data focusing on series and parallel of hotspots faults not just on a known fault. Among these classifiers, the Artificial Neural Network (ANN) emerges as the most suitable machine learning technique for early detection of PV hot-spots, exhibiting an impressive detection accuracy of 97% when appropriate data samples are employed. The proposed model can be implemented to increase the efficiency of monitoring and fault diagnosis of PV panels.
DETERMINATION OF R-FACTOR USING NONLINEAR ANALYSIS FOR R.C SPECIAL FRAMES CONSIDERING SPAN VARIABILITY
(2022-07-31) Yacob abu Hantash
Background: The Response Modification factor (R-factor) consider as the most important seismic design parameters, it is describing the amount of damping and inherent ductility in the structural system during an earthquake and it is used in general to reduce the actual seismic force to a design force, due to the inelasticity of the structure. Each of the global building codes gives a different procedure to describe the R-factor and give a different value, moreover, the R-factor is a nonlinear factor and it is very complicated thus, any change in the structural system leads to a different value of the R-factor. Objectives: This thesis gives a comprehensive procedure to calculate the R-factor and then highlights the relationship between the R-factor and the relative stiffness between beam and column. To date, there is no guideline as to how R-Factor would change due to variation of the relative stiffness between beam and column. This thesis comes as a step toward check the code values of the R-factor under the changing of relative stiffness between beam and column. Methodology: To achieve the above mention goal, a nonlinear static pushover procedure is used to obtain the inelastic behavior of the structure. SAP2000 program is used to generate the nonlinear capacity curves through incremental displacement control nonlinear analysis with concentrated plasticity in the plastic hinge within the structural element, XTRACT program is used to generate all the moment curvature curves for all structural members that are used to define the plastic hinges in SAP2000 program. Tow building layouts were used in the study, one is a uniform span length with a different number of floors and a different number of bays, and the other is a nonuniform span length with a different length ratio between spans. Results: The results show that the R-factor increase as the number of floors increases, also, as the number of bays increases the R-factor will increase and get close to a recommended code value, on the other hand, increasing the length of spans has a negligible effect on R-factor. The R-factor is minimum in the nonuniform cases, for example, the case with a nonuniform span length and three bays (6, 2, 6) meter length and with five floors has a value of R-factor 6.22 which is less than 8 (the IBC 2018 code R-factor for all SMRF). This means that using the IBC 2018 value of the R-factor would give lower induced seismic force for the design and may lead to a detailing level that does not warrant the realistic R-factor for the building being designed. Conclusions: The study gives a methodology to study the relationship between the R-factor and any variable that affected the structure’s response. As a future topic, it is recommended to repeat the work using a nonlinear dynamic procedure like time history analysis using actual earthquake records to compare the result with the actual earthquake loads in these building. Keywords: R-Factor, Pushover method, nonlinear procedure, Plastic hinge definition, ductility.

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