Natural Sciences

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https://hdl.handle.net/20.500.11888/18293

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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.
Investigating Cleaner Production Best Practices in Olive Oil Industry in Palestine
(2019-05-25) Nashaat Ziyad AL-Othman
Cleaner production techniques were adopted to develop the best practices of the olive oil extraction process industry in Palestine. The needed data were collected through a data collection tool “questionnaire.” This questionnaire was designed to be consistent with the used technologies in the Palestinian olive oil extraction processes, the data was then collected through interviews and brainstorming sessions with the stakeholders, after that the data was analyzed and evaluated according to the different analytical tools to generate the best practices (options) of cleaner production opportunities related to this industry. Based on the interviews and walkthrough with stockholders, the olive mills in Westbank general characteristics of OMW, and material balance analysis for input and output material, it was concluded that an environmental management system is needed to manage the OMW in Palestine. Different cleaner production options have been presented and elaborated. An evaluation tool was developed to grade and rank cleaner production options to seat the priority for implementation. The management and treatment option should be environmentally friendly to reduce or eliminate the OMW; the olive-mills management system has been analyzed from harvesting to end-of-pipe. A comparison between olive oil extraction was made, three-phase decanter the most popular in Palestine; due to mass production and acceptable quality, the environmental impact not considered and important for many. Two phase decanters in Palestine Not desirable; due to high investment cost and expensive disposal of by-product and wastes. Keywords: Cleaner production techniques, Olive Oil Extraction Processes, Tow-phase Decanter, Three-phase Decanter, cleaner production options, Waste reduction, good housekeeping.
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%.
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.
INVESTIGATING FIRM’S LOGISTICS PERFORMANCE IN THE PALESTINIAN OCCUPIED TERRITORIES DURING THE COVID-19 PANDEMIC
(2022-05-16) Saja Aziz Asad Khalili
Abstract Theoretical Background: Logistics is considered as a complex business and one of the dynamic activities that is increasingly seen as an essence competency of the firm, and plays a major role in the competitiveness and economic growth of firms. In light of the COVID-19 pandemic outbreak that caused two global crises; the health and the economic crises; and therefore has an effect on logistics performance that is a crucial for any firm to sustain its competitive advantage. An occupied territory in general lacks stability and security, in addition to lack authority and control over their own resources and revenues. In regard to logistics, occupying power imposes movement restrictions on the movement of goods, along with an overarching stranglehold over infrastructure; that leading to create disruptions for trade and the weakening of the economy. More importantly, these consequences were also increased simultaneously with the outbreak COVID-19 pandemic. Aims: The aim of this thesis is to study the critical factors affecting firm’s logistic performance in Palestinian occupied territories and the impact of COVID-19 pandemic on it. A conceptual model was designed to investigate the relationship between five constructs: logistics efficiency, political environment, logistics effectiveness, logistics performance, and firm’s performance. Methodology: The research model was analyzed by using partial least squares structural equation modeling by using SmartPLS software. The quantitative data were collected via e-mailing a questionnaire, in total 51 responses were received from four different sectors firms: trade, industry, service, and logistic sector in West Bank. Results and conclusions: The findings revealed that there is a positive and significant relationship between factors, where the relationship between “logistics performance” and “logistics effectiveness” has strongest influence, followed by the relationship between “firm’s performance” and “logistics performance”, while the relationship between “logistics effectiveness” and “logistics efficiency” and between “logistics effectiveness” and “political environment” have almost the same relationship and the least influence. Also, the findings revealed that the spread of COVID-19 pandemic was caused a negative impact of firm’s logistics performance in Palestine, especially the economic growth. Keywords: COVID-19, logistics, firm performance, political environment, PLS-SEM.
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.
THE IMPACT OF TELEWORK ON EMPLOYEE PERFORMANCE DURING COVID-19 CRISIS: THE CASE OF IT COMPANIES IN WEST BANK
(2022-06-23) Heba Asmar
Abstract Background: During the COVID-19 pandemic in 2020, enterprises were forced to go into telework mode. This shift was a big challenge for companies and employees to maintain the required level of performance due to a lack of telework experience. So, the purpose of this research is to study the impact of mandatory telework on employees' performance by checking organizational support and teamwork especially by examining technology as a mediator factor. To the best of our knowledge, there is no empirical evidence of the effect of mandatory telework on employees’ performance in the literature, and no such study has ever been conducted in Palestine as a developing country. Besides, no previous study has examined the effect of technology on telework performance as a mediator variable. Objectives: Therefore, this research seeks to answer the following research questions: first, "How is the effect of teamwork, organization support, and technology on telework performance?” and second “Does technology mediate/improve the relationship between teamwork, organization support, and telework performance?”. Methodology: Thereby, this research undertakes a thorough literature review and proposes a conceptual model tested on software employees in IT companies in West Bank. A questionnaire was used as part of the methodology containing 21 questions based on a literature study and previous research on the topic. Partial Least Squares analyzed the result–Structural Equation Modeling (PLS-SEM) statistical software. The effective response rate is 58.28%. Results and Conclusions: The obtained results based on a sample of 176 software employees show that organizational support, teamwork, and technology affect telework performance positively. Furthermore, results confirm that technology is a significant mediator in the relationship between organizational support, teamwork, and teleworking performance. This thesis contributes to the extant theory of telework performance in developing countries and how organizational support, teamwork, and technology as mediating factor affect employees' performance. In practice, this study helps software companies to implement telework and obtain high-performance indicators from employees by exploiting the best technological and administrative resources, thus, facilitating the successful implementation. Keywords: Telework, COVID-19, Pandemic, Performance, Teamwork, Technology, Organizational Support, PLS-SEM.
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.
SYNTHESIS, SPECTRAL CHARACTERIZATION, AND BIOLOGICAL SCREENING OF CURCUMIN BASED AZO DYES AND AZO-DYES METAL COMPLEXES
(2022-08-13) Ala'a Abed Al-Raheem Janem
Abstract Background: Curcumin is a natural active, vital, and important component derived from Curcuma longa. A significant attention was given to curcumin and its derivatives due to their natural origin, non-toxicity also to their bio functional properties including antioxidant, anti-inflammatory, antitumor, and anti-cancer. Objectives: The main objective of this work is to develop a new set of curcumin derivatives with broad spectrum of bioactivities. Curcumin-based azo compounds and curcumin with alkyl sulfonate moiety were selected to achieve the target objective. Methodology: The method synthesizing curcumin derivatives involves converting some aromatic amines with chlorine, sulfonyl, carboxyl, and ammonium groups to diazonium slat then coupling the diazonium salt with curcumin to produce curcumin-based azo compounds and direct condensation of curcumin alkali with sultone. Results: The newly prepared compounds were characterized by 1H NMR, 13C NMR, FT-IR and melting point. The azo compounds performance as dyes were evaluated. The color change of the azo as a factor pH were studied. The bioactivities of the azo compounds and complexes such as antimicrobial and anticancer wereevaluated (Escherichiacoli, Staphylococcus aureus, klebsiella pneumoniaand Methicillin-resistant Staphylococcus aureus,MCF-7, HEPG2, B16-F110, Colon and HeLa cell lines viability MTT assay in Palestine). Conclusion: A new novel set of curcumin azo dyes and curcumin with alkyl sulfonate moieties were successfully prepared. The antimicrobial and anticancer activities were very promising, which make the compound possible future drugs for treatment of various kinds of cancer. Keywords: Curcumin; Azo; Anticancer; Curcumin Sulfonate; Sultone, Genotoxic.
THE EFFECT OF BEAM ECCENTRICITY ON THE LOAD CARRYING CAPACITY OF REINFORCED CONCRETE WIDE BEAM-COLUMN JOINT
(2022-08-28) Suliman Ghazi Omar
Abstract Background: The beam-column joints of reinforced concrete (RC) are one of the elements in RC structures that have significant influence on the load transfer path. Buildings use two types of RC joints based on beam width: conventional joints and wide beam-column joints. Objective: The advantages of the wide and shallow RC beam-column joints in frame system are more economical, easier to build, provide a flexible space and less obstruction. This system is most used in Middle Eastern countries and hence is selected to be the subject of this study. The system consists of a one-way monolithic ribbed slab that is supported by concealed and wide beams. In some cases, the wide beam-column joint has eccentricity due to architectural considerations, where the center of the wide beam does not coincide with the center of the column. Methodology: The structural behaviour of eccentric wide beam-column joint is not fully understood due to the limited experimental research compared to those of conventional frame structures. This research concentrates on the effect of eccentricity on the load carrying capacity of RC edge wide beam-column joint within moment resisting frame (MRF). Finite Element (FE) analysis using (ABAQUS) is conducted to investigate the moment capacity of RC wide beam-column joint. The model is validated based on available experimental results. Results: and the results are further used to compare the change in bending moment capacity of the beam with and without eccentricity where the present of eccentricity produce additional torsion on wide beam and therefore reduce the bending moment capacity. Conclusion: An analytical approach is developed to predict the torsional moment on wide beam and use it to find the bending moment capacity. The proposed approach is derived based on principles of mechanics and equilibrium. The results from the approach are found to be consistent with the FE results. Keywords: eccentricity, wide beam, edge beam, wide beam column joint, eccentric wide beam-column joint, bending capacity, torsional moment on edge beam.
Hybrid Vehicles for Nablus Intra-City Public Transportation: An Environmental and Economic Feasibility Study
(2022-09-21) Sharif Bassam Salman
Abstract Background: There is a worldwide concern about the serious increase in exhaust emissions from vehicles that use traditional fuels, such as diesel, and the rise in fuel prices. Palestine is no exception. Nablus, the second largest city after East Jerusalem, has several types of topography, and suffers from traffic congestion. Within its urban area, traffic flows at low speeds, and drivers are normally forced to stop-and-go operation. This increases fuel consumption and the emission of exhaust gases of the diesel - operated public transport (PT) vehicles. Objective: Against this background, this thesis explores the possibility of introducing alternative fuel vehicles (hybrid vehicles) particularly to Nablus urban public transportation. Methodology: Interviews were conducted and a questionnaire was administered to a randomly chosen sample of PT drivers and route managers to obtain the operational characteristics of PT route and its associated costs and expenses. The existing financial aspects and environmental impacts of diesel vehicles were also analyzed. Results: Three scenarios were developed. The first scenario is replacing old cars (2009 or older) with hybrid vehicles. This scenario would provide 17.5% to 31% saving of fuel on an average of 20.9% for all PT routes, and reduction of exhausts CO by 33%, CH+NO by 88%, and PM by 93%. The second scenario is replacing all vehicles produced between 2009-2014. This scenario would save 15% of fuel and reduce exhaust gases by 35%. This gives this scenario an importance in the long run, and there is no urgency for implementation at present. Finally, the third scenario is replacing old diesel vehicles with 7-passenger vans. This would save 31% of fuel on the economic side, and lead to a 33% reduction in exhaust gases in general. Conclusions: The comparison between the three scenarios shows preference for the first scenario at present, while implementing other scenarios gradually. The first scenario is simple and close to reality, as old vehicle should typically be replaced; therefore, the study concluded that it would achieve financial and environmental benefits if PT went hybrid. The study recommends setting up national level policies to encourage the use of alternative fuels, with particular focus on public transportation. At the same time, such policies should also include the transportation sector, in general. Keywords: Public transport (PT), Vehicles, Emission, Hybrid, Diesel.
RASHBA AND DRESSELHAUS SPIN ORBIT EFFECTS ON THE MAGNETIZATION AND MAGNETIC SUSCEPTIBILITY OF INAS- QUANTUM WIRE
(2022-09-25) Wafa Haj Mohammad
Abstract Background: Nanomaterials play an important role in our life due to their potential in a wide range of device applications. Nano-materials are classified, according to their dimensions, into four types: Bulk, quantum well (QW), quantum well wire (QWW) and quantum dot (QD). A lot of research has been conducted on the properties of InAs QW and QWW material in the presence of an electric field. This study has looked at the magnetic properties of InAS QWW material under Rashba, Dresselhaus and the magnetic field effects. Transverse confinement potential was also taken into account. Methodology: Magnetic properties, like magnetization and susceptibility for InAs quantum well wire (QWW) material, have been studied theoretically under applied external magnetic field, with spin orbital interactions (SOI) like Rashba and Dresselhaus effects. The Hamiltonian of a single electron, confined in a QWW, has been solved by exact diagonalization method to obtain the eigenvalues and eigenfunctions of energy states as a function of QWW physical parameters. The researcher computed the average energy and the eigenstates of energy sub-bands that split under external magnetic field, using Rashba effect and Dresselhaus effect. Magnetization and susceptibility were studied and the oscillating behavior of the curves were observed as a result of mixing energy sub-bands of QWW spectra. Transverse conferment potential was taken into account. The average energy was studied under three effects with an external magnetic field. The magnetic properties were studied as well. Results: The calculations showed clearly that the Rashba parameter was an important and effective factor in controlling the magnetic properties of QWW material type. Dresselhaus parameter was also an effective factor but was weaker than Rashba effect. The Transverse confinement potential had a marginal effect on magnetic properties of InAs-QWW material. However, the temperature showed a significant effect on the magnetic properties of the conceded QWW. When T increased, the average energy would increase, too. Therefore, magnetization M and susceptibility χ behaviors would accordingly change. Conclusion: Rashba parameter is an important and effective factor that can control the magnetic properties of InAs QWW material. Dresselhaus parameter can also control the magnetic properties, but it is weaker than Rashba parameter. The Transverse confining potential has a marginal effect on magnetization and susceptibility of InAs-QWW material. Keywords: InAs QWW, Rashba, Dresselhaus, magnetic field, magnetization, susceptibility.
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.
OLIVE INDUSTRY SOLID WASTE WITH IONIC FUNCTIONALITY: PREPARATION, THERMAL BONDING AND USE AS A METAL ADSORBENT FROM WASTEWATER
(2022-11-21) Angham Jamal Ahmad Salahat
Background: The most important resource for life's survival is water. Unfortunately, Due to the fast growth of population, increase global industrial activities, careless utilization of natural resources, water pollution crosses the limits. Contaminated water with hazard’s heavy metals from industrial and agricultural sources is one of the most critical issues that World Health Organization (WHO) and researchers focusing and searching for suitable solutions to eliminate it. Modifying existing polymers may be the simplest and most productive way to develop a low-cost adsorbent with high efficiency against metals and hazardous organic compounds. Objectives: The purpose of this study was to establish a natural source and low-cost technique to make a new adsorbent for hazardous metal ions. What distinguish our study is the use of a raw natural polymeric materials, usually a commercial polymer used at other studies. Methodology: Adding carboxylate functionality to Olive Industry Solid Waste (OISW) components (cellulose, hemicellulose, and lignin) by CMC reaction, after subjecting the waste to purification by Soxhlet extraction, followed by thermal treatment produced Carboxymethylated OISW polymer a novel polymer with new ionic functionality. Results: The polymer was characterized using FT-IR, TGA, and AFM, to examine the polymers structures and its thermal stability, and to obtain a Nano scale image of the polymer surface respectively. Degree of substitution and solubility of the produced polymer were also determined. Carboxymethylated OISW polymer was tested as a Pb(II) and Cu (II) ions adsorbent that were used as model ions in this study. Metal ion concentration, temperature, pH, adsorbent dosage contact time and shaking speed were all evaluated as parameters influencing the adsorption process. The percentage removal of Pb(II) by carboxymethylated OISW polymer was about 85 percent rate, and that of Cu(II) was 93 percent. Adsorption isotherm, kinetics, and thermodynamics were also investigated in order to obtain a better knowledge of adsorption spontaneity and mechanism. As determined by the adsorption parameters, Langmuir isotherm of adsorption, and Freundlich isotherm model was tested. Equilibrium reaction with Cu(II) obey Langmuir isotherm model, and pseudo-second order reaction, also for Pb(II) results shows that Langmuir isotherm model obey, and pursues a pseudo-second order model. Also, the reaction thermodynamics indicates that the adsorption process is spontaneous. Conclusion: Adsorption efficiency of the Carboxymethylated OISW polymer was evaluated on a real-wastewater (sewage) sample as well. The polymer showed quantitative removal for most of the toxic metal ions present in wastewater not just lead and mercury. Keywords: Carboxymethylated OISW polymer; Copper; Heavy metal; Lead; Olive industry solid waste; Water pollution, Water treatment,
NUMERICAL SOLUTIONS OF SYSTEM OF FREDHOLM INTEGRO-DIFFERENTIAL EQUATIONS
(2023-01-29) Ansam Mohammad Zaidan
Abstract Background: System of Fredholm integro-differential equations is a hot topic in applied mathematics; in particular, the field of signal processing, neural networks and the development of telecommunications. Aims: This thesis presents some numerical methods based on matrix polynomials to solve system of Fredholm integro-differential equations. These methods are: Laguerre polynomials, Bessel functions and Legendre polynomial. Methods: In this study, we use Matlab software to implement these methods in form of algorithms to solve some numerical examples. Results: Numerical results show that the convergence and accuracy proprieties of these methods are in good agreement with the exact solution. Conclusion: A comparison of numerical results illustrated in tables and figures shows that the Laguerre polynomials method provides more accurate results than the other methods and therefore more effective. Keywords: solution of system, fredholm, integro-differential, matlab, numerical methods, integrodifferential.
OPTIMAL CONTROL FOR LINEAR DYNAMICAL SYSTEM WITH ZERO INITIAL CONDITIONS
(2023-03-05) Yafa Nihad Abdel Afou Abdel Aziz
ABSTRACT The main focus of this study is on the Linear Dynamic Systems With Zero Initial Conditions. Also the following topics are presented: Optimal control, state space representation, Lyapunov equations, controllability, observability and their Gramians. Some model order reduction methods are also proposed, specifically balanced truncation and singular perturbation approximation. For the optimal control problems, the study used Feedback control strategies, numerical solution methods and their implementation with various illustrative applications. A linear quadratic regulator (LQR) is introduced to develop an optimal control that minimizes the quadratic cost function by employing the formal asymptotic solution for the underlying algebraic Riccati equation. This final optimal control was delivered by implementing three types of singular perturbation approximation to test the best performance in closed-loop conditions. A few numerical examples were given to illustrate one type of singular perturbation approximation and show how the reduced-order may be used to approach the optimal control of the original system. Numerical results for the clamped beam model and the RLC circuit have shown that singular perturbation approximation method is one of the most efficient methods for model order reduction. Keywords: Dynamic systems, Model Order Reduction, Singular Perturbation Approximation, Optimal Control.
QUALITY 4.0 FRAMEWORK IN THE CONSTRUCTION INDUSTRY IN PALESTINE
(2023-03-20) Nasreen Abdel Hafeeth Altuhul
Abstract Many business sectors have been developed in the current rapidly evolving market while others are lagging behind this development such as the Construction Industry (CI). This study gives an overview for Quality 4.0 concept and investigates the relationship between Contract Management System (CMS) with Quality Management System (QMS) in presence of Quality 4.0 acceptance and implementation (Q4.0) as a mediating variable in the construction contracting companies working in West Bank in Palestine. A conceptual literature-based framework was developed to connect between variables using exploratory research. Structured questionnaire was designed to collect data from a randomly selected sample; 95 responses from contracting Palestinian companies were gathered. Partial least squares structural equation modeling (PLS-SEM) using Smart-PLS software was used to analyze and assess the conceptual framework. The results revealed that CMS and QMS are implemented at a high level in the targeted construction companies. Moreover, Q4.0 technological dimensions are highly accepted by these companies. It has been found that; Claims and Disputes Resolution (CDR), Communication and Relationship (CR), and Contract Risk Management (CRM) followed by financial issues are main contractual management dimensions to be developed in this industry. Additionally, the results confirmed that CMS and Q4.0 have significant positive effect on quality management system. On the other hand, results showed that there is no significant impact of Q4.0 on CMS and no mediation effect of Q4.0 acceptance and implementation on the relationship between CMS and QMS. This study contributes in giving empirical evidence about the relationship between CMS, QMS, Q4.0 and recommends that other studies be done to assess the effect of other variables on QMS and to retest this model with in other industrial sectors with alarger sample size so that the results can be generalized. Keywords: Contract Management System (CMS); Construction Industry (CI); Quality; Quality 4.0 (Q4.0); Quality Management System (QMS).
EXISTENCE OF PATTERNS FORMATION FOR AN AGGREGATION-DIFFUSION SYSTEM IN 2-D
(2023-07-23) Alaa Anwar Mustafa Hardan
Abstract In this thesis, the researcher introduced the aggregation-diffusion equation in two-dimensional space and investigated the existence of steady-states, which contain several states, some of which are trivial and some of which are not. The categories studied numerically using the finite-volume method, then followed by the use of the third-order SSP-RK method, and finally used MATLAB to clarify the state of stability in each case. The categories are divided into three main categories depending on the value of theta, one of which diffusion prevails, while aggregation dominates, and the last one, in which the balance between diffusion and aggregation wins.
نحو قرية فلسطينية بيئية - تقييم تجربة قرية فرخة
(2023-10-01) هديل فهمي يوسف بدح
يشهد كوكب الأرض تغيّراً كبيراً وظواهر بيئية سلبية خطيرة سببها الإنسان؛ بسبب الممارسات الخاطئة التي تؤدي إلى تلوث البيئة، والاستخدام غير المستدام للموارد الطبيعية، الأمر الذي يدعو للتفكير بطرق لحماية البيئة؛ للحصول على حياة مستدامة وأكثر أماناً. هذه المشاكل قد تكون أكبر وأصعب في فلسطين بسبب الاحتلال، لذلك يجب العمل على إيجاد حلول للمحافظة على البيئة لنا وللأجيال القادمة. وتُعدّ القرى البيئية من الحلول التي يجب أن تنتشر في فلسطين؛ لتعزيز التنمية المستدامة الشاملة. وتقوم فكرة القرية البيئية على تحويل المجتمع العمراني إلى مجتمع متكامل مستدام بيئياً. من هنا تأتي أهمية البحث، كون قرية فرخة أول قرية بيئية فلسطينية وتم استخدامها كحالة دراسة لهذا البحث؛ وذلك لتوضيح فوائد القرية البيئية للمجتمع عموماً والمجتمع الفلسطيني خاصة، والذي بدوره يعزز توجه الاستدامة والسياحة البيئية في فلسطين. هدفت الدراسة إلى تقييم وضع قرية فرخة وإلى أي مدى تعتبر قرية فرخة بيئية من خلال أبعاد القرى البيئية الأربعة، بحيث يمكننا تقييم مبادئ القرى البيئية الستة من خلال هذه الأبعاد، كما وتهدف الدراسة إلى التعرّف إلى مدى استفادة أهل القرية من كون القرية قرية بيئية في فلسطين، وتحديد مواطن الضعف في القرية ومعرفة أسبابها للقدرة على معالجتها. وتم تحقيق هذه الأهداف عن طريق استخدام المنهج النوعي والتحليلي، وتم الاعتماد على المنهج التاريخي والنظري في جمع البيانات ذات الصلة بالقرى البيئية، كما تم اتباع منهج دراسة الحالة كون قرية فرخة أول قرية بيئية فلسطينية. تم اعتماد المنهج التحليلي من خلال عمل استبيانين، الأول بناءً على مبادئ القرى البيئية مقسمة إلى ستة أقسام (العيش المستدام، وإدارة النفايات، وتحسين الصحة والبيئة، والإدارة المثلى لموارد الطاقة، والإدارة المثلى للمياه والزراعة، والتنمية الثقافية والاجتماعية) لتحليل الوضع الحالي لقرية فرخة، وعمل استبيان ثان خاص لأعضاء مجلس قروي فرخة يتضمن الأبعاد البيئية الأربعة، وهي مجالات التجديد (البيئية، والاجتماعية، والثقافية، والاقتصادية) مرتبة حول مسار مركزي واحد وهو التصميم المتكامل، لتكوين خريطة التجديد الخاصة بقرية فرخة من خلال ربط المبادئ البيئية الستة بالأبعاد البيئية الأربعة. وتم التوصل إلى أن قرية فرخة لديها بعض مقومات القرية البيئية، ولكن تواجه مشاكل كبيرة تستدعي الحل لخلق بيئة صحية للعيش فيها بطرق مستدامة، بالإضافة الى التوصيات لتحسين جودة الحياة والعمل على إنجاح العلاقة بين السكان والبيئة، ولتحسين أداء القرية البيئية واحتياجاتها بطريقة مثلى بناء على مبادئ القرى البيئية، أيضا دليل لإنشاء القرى البيئية في فلسطين. الكلمات المفتاحية: القرى البيئية، مبادئ القرى البيئية، الاستدامة، التصميم الحضري، خريطة التجديد، التصميم الإيكولوجي، الموارد الطبيعية.
TAILORED FUNCTIONALIZATION OF HETEROCYCLIC DERIVATIVES OF CARBOXYLIC ACIDS AND IMINES: SYNTHESIS, CHARACTERIZATION, AND BIOLOGICAL IMPLICATIONS
(2023-10-05) Inas Ibrahim Mahmoud Bsharat
Abstract Background: A large number of different natural and synthetic chemicals depend on heterocyclic molecules as key building blocks due to their different structures and properties. In the presence of many drugs based on heterocyclic structures, the study of heterocyclic compounds is a prominent area in organic chemistry and has several uses in numerous industries. Objectives: In this study, a group of ester, amide and imine compounds were prepared, and they were studied as antibacterial and anticancer, and some of them were studied as antioxidants. Methodology: All the novel ester, amide and imine compounds in this study were prepared by condensation reactions of heterocyclic compounds, and then the new compounds were identified through FT-IR and NMR analysis, and their biological properties were tested and studied. Results: All prepared heterocyclic compounds showed effective biological activities in varying proportions. Ee1 and E4 were the best bioactive esters in all assays. Amide A1 showed remarkable biological activity, and imines 4 and 6 were the best imines in all biological tests. Conclusion: In this study, thymol ester E2 was better at preserving normal muscle cells than thymol. The E4 carvacrol ester compound was the best compound in its group, as it showed anti-cancer activity against HepG2 liver cancer cells in cytotoxic assay and against MCF7 breast cancer cells in cytostatic assay and also gave a distinctive activity against all types of bacteria studied. Ester compound Ea was more effective against MCF7 breast cancer cells in cytotoxic assay and against PC3 prostate cancer cells in cytostatic assay. The ester compound Eb performed better in cytotoxic and cytostatic tests on HepG2 liver cancer cells and MCF7 breast cancer cells, respectively. Ester compound Ec was more effective against Hela cancer cells and MCF7 breast cancer cells, respectively, in cytotoxic and cytostatic experiments. Also in both cytotoxic and cytostatic experiments, the ester compound Ed was more efficient against HepG2 liver cancer cells. Flavonoid ester Ee1 gave a distinctive activity in all biological tests. Amide compound A1 was the best of the compounds of its group on all the studied biological activities, as were imine 4 and imine 6 as well. Keywords: Heterocyclic compounds; Antibacterial; Anticancer; Antioxidant.

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