Natural Sciences

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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.
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.
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.
BIOBASED POLURETHANE FOAM PREPARATION WITH CATIONIC AND ANAIOIC RECEPTORS: DESIGN SYNTHESIS AND APPLICATION IN WASTEWATER PURIFICATION
(An-Najah National University, 2025-09-30) Abu Leil, Bahia
Heavy metal contamination in drinking water can harm organs and is a major cause of cancer and other serious conditions. Metal- and dye-binding polymers are effective in adsorbing and removing dyes and toxic metals from water. This study aims to synthesize a range of bio-foam polymers featuring diverse functional groups and polymer architectures, with the objective of evaluating their efficacy in removing dyes and heavy metals from contaminated water. Furthermore, a protocol was established for the extraction of these metals and dyes from solution. Bio-foam polymers were prepared, and cellulose was used as a bio-based polymer. Four polymers with several coordination sites for metal ions and dye adsorption from sewage were synthesized. Efficiency of adsorption was studied for Cd(II) and methylene blue dye was investigated as a function of adsorbent dose, concentration temperature, pH, and time. The optimum parameters with highest adsorption efficiency were determined. The polymer on foam form were prepared from cellulose using a method composed of several steps. The first step involves cellulose oxidation to cellulose aldehyde using 2,2,6,6-Tetramethylpiperidine 1-oxyl (TEMPO)/sodium hypochlorite in alkaline medium to produced cellulose aldehyde which was reacted with cysteine to produce cellulose functionalized with amin acid functional group (Cell-Cs-H) which then crosslinked with 1,6-hexamethylenedisiocayante and 1,4-pehenylenediisocyanate to produce cellulose based foam with amino acid functionality Cell-Cs-H and Cell-CS-P, respectively. The produce form then converted to zwitterionic polymers by reacting them with 1,3-proane sultone to produce Cell-Cs-H-S and Cell-Cs-P-S, respectively. All polymers were analyzed by FTIR, SEM, and TGA. All polymers showed excellent efficiency toward methylene blue and methyl orange dyes in addition to metal ions. The diversity and frequency of the coordination was the reason for the high extraction efficiency of the foams, it was almost quantitative for both dyes and metal ions, especially for foams with zwitterionic functionality. The thermodynamic analysis results (The Gibbs energy (ΔG0), enthalpy (ΔH0), and entropy (ΔS0) were calculated) supported the spontaneous adsorption efficiency of the polymer at room temperature. The kinetic study revealed that the metal ion and dye adsorption by polymers was pseudo-second order and followed the Langmuir isotherm model.
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.
Co₂MnSi, FULL HEUSLER COMPOUND FOR SOLAR CELL APPLICATIONS
(An-Najah National University, 2025-09-03) Najjar, Samer
The simulations for this thesis were performed in COMSOL Multiphysics, which is one of the most commonly used platforms for scientific modeling and analysis. This project proposed a three-layer solar cell design, with particular emphasis on one of the crucial layers, the absorber layer. In this study, was evaluated the performance of a Full Heusler compound (Co₂MnSi) against traditional materials such as silicon and perovskite. During the simulation process, the temperature was held constant at 298 K, and the absorber layer thickness was varied from 100 nm to 700 nm for all three materials to allow for a fear comparison. For all materials, an initial applied voltage of 0-0.55 V led to nearly identical length quantities at first. When the voltage reached above to range 0-1.2 V, performance degradation was detected, but no significant difference was found otherwise. The presented method provides short circuit current density Jsc, open circuit voltage Voc, and fill factor FF for sub-cells measuring current in both forward bias and reverse bias, without compromising overall cell performance. An efficiency as high as 41.41% is achievable with the heusler compound Co2MnSim surpassing the performance of silicon and perovskite-based structures in this regard. In addition, several graphical analyses were obtained (I–V, J-V and P–V characteristics), were conducted to demonstrate the behavior of these three materials under different operating conditions. These results reveal that Co₂MnSi is a good candidate for an advanced absorber material in the next-generation photovoltaic device.
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.
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.
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.
DETERMINING SUITABLE SITES FOR RAINWATER HARVESTING PONDS USING GEOGRAPHIC INFORMATION SYSTEMS (GIS) IN TULKARM GOVERNORATE
(2023-12-19) Adham Jihad Dibas
This study uses geographic information systems to study rainwater harvesting and methods to exploit it in the Tulkarm Governorate. It aims to calculate the amount of surface runoff to analyze the water budget in the study area and determine periods of water surplus and deficit, which will benefit the agricultural sector in exploiting periods of a water surplus when the soil is saturated and does not suffer from a lack of moisture. It also identifies water deficit periods when a lack of soil moisture may affect crops. The modified Thornthwaite (1955) method was applied to calculate the water balance, monthly and annual rainfall averages, and temperatures between 2011 and 2020. The results show that the average amounts of surface rainwater runoff in the governorate reach 186 mm annually. There are two periods of spatial distribution of soil moisture: a period of water surplus extending from December to March and a period of water deficit from May to October. January has the highest water surplus, reaching 129 mm; July and August have the highest water deficit, reaching 170 mm. These are consistent with the climate features that this region experienced during that period. The results also show that the locations closest to the outlets of the main water streams are the most suitable locations for establishing a water collection pond. Therefore, the main effort in this research focused on collecting rainwater in specific locations during the period of water surplus by creating harvest ponds, especially during the first precipitation periods. Keywords: Rainwater harvesting, Water budget, Tulkarm Governorate, Palestine, GIS.
DEVELOPMENT AND VALIDATION OF SMART-PHONE APPLICATION FFQ SCREENER FOR ASSESSING CHOLESTEROL INTAKE AMONG PALESTINIAN POPULATIONS
(2023-10-21) Amneh Abdel-Aal
Abstract Background: Cholesterol is an essential material existing in each animal cell and has many functions that are related to the body's health. However, additional intake of dietary cholesterol is related to elevate cardiovascular diseases (CVDs) incidence. The US Department of Agriculture (USDA) recommends cholesterol intake to be lower than 300 mg/day. On the other hand, using technology in diet assessment is considered an effective and alternative way to conventional procedures such as food frequency questionnaires (FFQ). The study aimed to develop and validate an FFQ screener of dietary cholesterol intake assessment using a smart phone app. among the Palestinian population. Methodology: One hundred participants from Palestinian populations, were shared by convenient sampling, aged from 18-60 years. The study was done in five stages; stage 1: development of FFQ screener. Stage 2: development of the app (Pal Chol app ®). Stage 3: content validity. Stage 4: test and re-test reliability. Finally; stage 5: criterion validity. Correlation; was done by Pearson correlation to assess the reliability and validity, and the difference between means was done also for the validity test. P-value<0.05 is considered statistically significant. Results: In the pilot study, there was a significant (strong) correlation (r=0.7, p-value=0.000) between the test and re-test results. For the validation study; the mean age was 26.24 ±7.15 years. The mean difference between cholesterol intake from the app. and 3 days of food recall was significant (p-value=0.000), and for a correlation; there was a correlation but week (r=0.31, p-value=0.006). Furthermore, the usability test of the app. was compared with 3 days of food recalls; the majority of participants confirmed the usability of this app. Conclusions: In our study, we were successful; in developing an FFQ screener; that specialized in the assessment of dietary cholesterol intake among the Palestinian population aged between 18 to 60 years. Nevertheless, we need further improvement and revision on the app. Keywords: CVDs, dietary cholesterol, FFQ screener, validation studies
EFFECT OF HORIZONTAL ECCENTRICITY ON THE RESPONSE REDUCTION FACTOR (R)
(An-Najah National University, 2025-08-05) Bustami, Haya
Structural irregularities significantly affect the seismic performance of buildings. Structures with architectural flaws may endure excessive twisting, differential story displacements, and probable collapse during seismic events. International standards, including ACI and ASCE, lack explicit directives for including the response modification factor (R) in the presence of horizontal eccentricity cases. The study aims to examine the impact of horizontal irregularity on the R factor for Intermediate Moment Resisting Frame (IMRF) structures. The study examines two variables: the number of stories and the amount of eccentricity. The study encompasses structures of 5, 7, 9, 12, and 15 stories, exhibiting eccentricity indicator values that vary from zero for reference specimens to 60% of the building width. SAP2000 is utilized for the analysis and design of buildings, incorporating response spectrum nonlinear analysis for seismic forces in accordance with ASCE standards. Push-over curves are produced to ascertain the correlation between horizontal eccentricity and R-value. Diverse push-over curves are utilized to examine various conditions. This encompasses standard push-over curves with flexural hinges, push-over curves incorporating mixed flexural, shear, and torsion hinges, as well as push-over curves reflecting the influence of bidirectional lateral pressures (push-over modal curves). The results demonstrate that the R-factor for the reference building corresponds with the recorded code value. Moreover, elevated eccentricity levels diminish the R-factor for buildings of identical height. As the elevation of the structure rises, the R-factor diminishes. The R-factor reduction varies from zero for the reference specimens to 25% for a fifteen-story with 60% eccentricity indicator. Utilizing bidirectional push-over curves that integrate integrated flexural, shear, and torsion hinges results in a 30% reduction in R-factors. For the majority of moderately tall structures, the reduction is approximately 15%. The decrease in the R-factor results from the development of plastic hinges on one side of the structure, causing abrupt failure of specific joints before the joints on the opposite side give.
EFFECT OF PERIMETER BRICK-CONCRETESTONE-MASONRY INFILL WALLS ON THE DEFLECTION AMPLIFICATION FACTOR FOR INTERMEDIATE MOMENT RESISTING FRAMES
(An-Najah National University, 2024-06-12) Masarwa, Khalid
Constructing of multi-story buildings using perimeter walls with stone cladding is very common in Palestine. The stone cladding provides an architectural aesthetic to the exterior facades of the buildings. The traditional method in Palestine to construct these walls is to fill the reinforced concrete frames with a three-layer wall. These layers are: brick, concrete, and stone. The walls may affect the behavior of the structure under an earthquake excitation. This results from their additional mass, lateral stiffness and strength that these walls add to the building. Neglecting the effect of these walls on the structural response can lead to a poor structural analysis prediction of the real structural behavior. Therefore, this study focuses on studying the effect of perimeter brickconcrete-stone-masonry (BCSM) infill walls on the deflection amplification factor (Cd) for intermediate moment resisting frames. The research methodology started by designing 36 cases according to ASCE7-16 and ACI 318-14 codes. In every case, the building is designed as an intermediate moment resisting frame. Nonlinear static pushover analysis is performed to generate load-deflection curves for different parameters using SAP2000 computer program. The results are used to estimate the Cd-factor under the variation of the parameters. In this study, it was found that the Cd-Factor is very sensitive to the presence of BCSM infill walls; it can lead to a significant change in the Cd-Factor compared to what is suggested by the ASCE7- 16 code. The results of this study showed that the increase of the BCSM infill walls opening ratio leads to a decrease in the Cd-Factor, and the increase of the BCSM infill walls length leads to a decrease in the Cd-Factor. Also, in this study, it was found that the Cd-Factor is not fixed with varying the number of stories of a building. In other words, it is not true that the increase in the number of stories will always increase the Cd-Factor and vice versa. Results were used to develop two simple formulas to estimate the Cd-Factor, and to help engineers in Palestine to estimate the Cd-Factor for buildings that have BCSM infill walls. Keywords: Macro modeling; Fiber hinges; BCSM infill walls; Cd-Factor; R-Factor; Equivalent compression struts; Overstrength.
ENHANCING THE EFFICACY OF A GROUND SOURCE HORIZONTAL HEAT PUMP BY CARBON NANOTUBES SUSPENDED IN WATER
(An-Najah National University, 2025-01-09) Khoswan, Ibrahim
This study explores enhancements in ground source horizontal heat pumps ((GSHHP)) by improving the heat transfer medium through nano-fluids. Researchers have used various types of carbon nanotubes (CNTs) in water. Both functionalized single-walled, Multiwalled carbon nano tubes ((MWCNT)s) with Tween 80 as a surfactant provided optimal suspension, while multi-walled CNTs achieved a 126% increase in thermal conductivity after sonication. Effects of various parameters, like concentration, shape factor, temperature, viscosity, aspect ratio, and added surfactant were studied. The result for (MWCNT) at the thermal conductivity increased with the concentration of (MWCNT) using Tween 80 using 10-60-minute sonication for each sample, no extra suspension would happen beyond that time, and the suspension concentration became saturated. The Thermal conductivity of (SWCNT)-water suspension was less for the same concentration (10% wt.) to reach k(SWCNT)nf= 0.77 W/m.K with a 28% improvement compared to water thermal conductivity kw = 0.6 W/m.K. Those results were better compared to the literature. The results revealed that smaller concentrations of (SWCNT) will be needed, which lowers both capital and running costs. making the system eco-friendlier. The concentration of CNTs influenced the specific heat capacity of the water-based nano-fluid. Higher CNT concentrations led to enhanced thermal conductivity but had mixed effects on specific heat capacity, diverging from typical predictions in the literature((SWCNT)s), ((MWCNT)s) impacted the specific heat differently. (MWCNT)s showed a more noticeable effect on increasing thermal conductivity, though the specific heat enhancement was less pronounced for (SWCNT)s at similar concentrations. Sonication time and the use of a surfactant (Tween 80) affected CNT dispersion in water. A simulation study further verified the experimental findings in both thermal conductivity and specific heat. New models of our experimental data were developed in this dissertation to predict specific heat thermal conductivity enhancement as a function of CNT concentration and nano-fluid properties. These models offered a more accurate estimation of specific heat changes compared to earlier theoretical models which were inaccurate. Also, the simulation of ((GSHHP)) described a qualitative model to rationalize the effects of (CNTs) on nano-fluid conductivity.
Excess Energy Management of Hybrid Standalone Renewable Energy Power System
(2021-12-12) Mai Abd-alatef Mohammed Abdo
Abstract Palestinian Territories suffer from high shortage of conventional energy and it imports all its needs of petroleum and about 90% of electrical energy needs from Israeli energy companies. The exploitation of the RES in PT for electricity generation is growing up and spread widely. There are a lot of rural areas on PT still suffer from continual interruption of power supply. This makes the implementation of stand-alone systems a feasible option. Better sizing of stand-alone systems increases the feasibility and reduce the simple back period .The excess energy causes technical problems to the systems as well as reduces its feasibility. The base proposed case is a stand-alone (off-grid) hybrid system includes PV, generator(diesel), and battery. The load is for small residential community in Jericho comprises of 10 households. The average load demand is 111 kWh/day. By using HOMER Pro software the optimum design was modeled and achieved. With actual solar radiation, load profile (electrical demand) for the residential proposed load and cost of all equipment. The base system consists of PV modules, batteries, generator(diesel), load and converter. The net present cost of base proposed system is USD 101,361. The Cost of energy is USD 0.194 /kWh. The contribution of RE is 92.2%. The surplus electricity is 7469 kWh/year about 13.8%. Different strategies and configurations are proposed to reduce and using the excess electrical energy produced from the base case: with water pumping system, with fuel cell system, with boiler water heating system, and with hybrid boiler water heating and water pumping system. The results showed the best hybrid is(PV/Diesel Generator/BSS with hybrid boiler water heating and Water Pumping System). With Analysis the surplus power and studying the residential load and the water pump and storage tank, a deferrable load is assumed. The results show feasible improvement in the amount of excess power, that the main purpose of this research regardless of NPC & COE, while the NPC & COE that have been studied to economical study just. The PV/Diesel Generator/BSS with hybrid boiler water heating and Water Pumping System is feasible strategy to electrify the residential load and the most economical system. The COE is USD 0.214/kWh. The NPC of the system is USD $140,220. The capacity of the PV system is 30 kW, 40 batteries of 1150 Ah each and 3 kW diesel generator. The proposed system provides the residential and pumping load and heating load with about no interruption to the power supply. Sensitivity analysis is used to study the impact and affections of variations in other parameters (PV cost, costs of extra equipment, diesel fuel price). Energy management procedure by this configuration to reduce the surplus electricity from 13.8 % to 5.3%.

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