Dhahran City Research Articles

Optimal design of concentrated solar power-based hydrogen refueling station: Mixed integer linear programming approach

This paper developed a mixed integer linear programming model to optimally design hydrogen refueling station coupled with an on-grid concentrated solar power. The model aims to minimize the total life cycle cost of the integrated system addressing various constraints. The utility of the proposed model is validated using hydrogen refueling station under the weather conditions of Dhahran city, Saudi Arabia. The station fulfills the daily hydrogen requirements of taxi-fleet in Dhahran city, estimating a daily demand of 4202 kg of hydrogen. The proposed hydrogen refueling station requires a solar field of 71,721 square meters to generate 50,233 MWh of energy annually. The on-grid concentrated solar power system is determined to produce an excess energy of 10,515 MWh which is exported to the grid, highlighting positive economic impact. The levelized cost of hydrogen of the proposed system is 7.17 $/kg. The achieved results validated the feasibility and efficiency of the proposed system, positioning it as a sustainable solution for meeting the rising demand for clean and green transportation in the region.

Novel approach for optimizing wind-PV hybrid system for RO desalination using differential evolution algorithm

Access to clean water is a basic human right, and reverse osmosis (RO) is a common method for producing potable water from seawater. However, the high energy demands of RO systems make them expensive to operate. Hybrid systems that combine renewable energy sources (RES), such as wind and photovoltaic (PV) systems, can reduce the energy costs associated with powering RO systems. In this paper, a novel approach that uses a differential evolution (DE) algorithm to optimize wind-PV hybrid systems for RO desalination is proposed. (DE) is a heuristic, population-based algorithm that searches for the global optimal solution. The approach aims to minimize the levelized cost of energy (LCOE) and ensure that Desalinated water costs are within an appropriate range. The algorithm was used in a case study of the city of Dhahran, Saudi Arabia, which faces significant water scarcity challenges. The results show that for an RO load demand of 1 kW, the optimized hybrid system's configuration includes a 26 PV panels with generation capacity of 7.67 kW, 2 wind turbines with 1 kW production capacity each and 9-battery storage system with 38.79 kWh storage capacity. The LCOE is 0.39 $/kWh for Dhahran city, and the cost of desalinated water falls between 1.98 and 2.16 $/m3, which is lower than the costs reported in the literature.

Waste heat recovery of two solar-driven supercritical CO2 Brayton cycles: Exergoeconomic analysis, comparative study, and monthly performance

The waste heat from a supercritical Brayton cycle has a great potential to be recovered. However, there is a lack of research regarding the utilization of these cycles in multi-generation systems. In addition, different multi-generation systems based on supercritical Brayton cycles have not been compared in the literature. In the present study, two multi-generation configurations based on two supercritical Brayton cycles, namely regenerative (configuration 1) and recompression (configuration 2), are proposed and compared from thermodynamic and exergoeconomic standpoints. In both configurations, an organic Rankine cycle, a domestic hot water heat exchanger, and an LiCl-H2O absorption refrigeration system are employed to convert the waste heat of the two supercritical Brayton cycles into useful energy. Meanwhile, a thermoelectric generator is used instead of a condenser for efficient waste energy recovery of the organic Rankine cycle. The generated electricity by the organic Rankine cycle and thermoelectric generator is used to generate hydrogen in a proton exchange membrane electrolyzer. In addition, a direct integration method is employed to integrate the two supercritical Brayton cycles with a solar power tower as the heat source. The final results regarding the net output power, exergy efficiency, and economic performances of the two configurations reveal the superiority of configuration 2 over configuration 1. Net output power and exergy efficiency of configuration 2 are 6.55 MW and 4.06% points higher than configuration 1. Moreover, total cost rate and unit cost of products for configuration 2 are 0.4 $s-1 and 10.03 $GJ-1 lower than configuration 1. On the other hand, cooling, heating, and hydrogen rates of configuration 1 are respectively 2.93 MW, 4.23 MW, and 2.84 kgh-1 higher than configuration 2. Moreover, the monthly analysis of the two systems for Dhahran city (26.3°N/50.2°E) as a case study indicates that the best thermodynamic performance of the systems is achievable in February, June, and July.

Factors Affecting the Household Income of Petty Traders during COVID-19 Pandemic in Dharan City

Petty trading is such a type of economic activity operating abundance of the low-earning population in new urbanizing developing countries like Nepal. The main aim of this study is to explore factors affecting the household income of petty traders during the COVID-19 Pandemic in Dhahran city. This investigation used descriptive analysis, and the Pearson correlation test to identify the relationship between dependent and independent variables. There were 48 petty traders conveniently selected for the convenient sampling to collect primary data by survey method. The data were analyzed through descriptive statistics by using SPSS. There is a significant relationship between daily household income and the marital status of petty traders. But there was no significant relationship between the daily household income and the size of the family, or the investment of capital of the petty traders. Similarly, the above results of this study suggest that this study is helpful to the planners and policymakers in Dharan city to formulate suitable policies and manage the micro-business sector including petty traders. And the government should create programs that preserve and establish the economic rights of petty traders and reduce the various complications and taxes which they usually impose on them. The study concluded that there is a significant difference between the household income of petty traders and the marital status of petty traders. Moreover, it established that there was no relationship between the household income and the family size, the investment of capital, and the income before COVID 19 of petty traders.

Estimation of Solar Radiation on a PV Panel Surface with an Optimal Tilt Angle Using Electric Charged Particles Optimization

Solar energy is a promising renewable energy source that can fulfill the world’s current and future energy needs. The angle at which a photovoltaic (PV) panel faces the horizon determines the incidence of solar radiation. The incident solar radiation on PV panels could be optimized by adjusting their tilt angles and increasing the power output of the PV array. In this study, solar energy model-based research was conducted in the Saudi Arabian cities of Dhahran and Makkah. This study investigated the performance of a 1 kW monocrystalline silicon PV array in these cities. Analyzing the optimal tilt angle for efficiency and performance improvement of the PV panel is challenging. The optimal tilt angle is determined by combining the data of the Sun’s diffuse, direct radiation and the global horizontal Sun radiation. This research examined the four empirical models by applying the electric charged particle optimization (ECPO) algorithm to estimate the solar radiation on sloped surfaces. The model’s results were compared to the global horizontal solar radiation based on the daily mean solar radiation value in these cities. The Hay–Davies–Klucher–Reindel model presented the maximum amount of tilted surface solar radiation in the year and at different periods. In contrast, the Badescu model exhibited the weakest results of all the isotropic and anisotropic models. Finally, using the ECPO algorithm, all models indicated that tilted surfaces (IT) received more solar radiation than horizontal surfaces (Ig).

Phthalates, non-phthalates, polychlorinated biphenyls, and phenyl phosphates in atmospheric suspended particulate matter of Dhahran City, Saudi Arabia: levels and seasonal variation

This is the first report to describe the seasonal variations, levels, and possible health effects of groups of persistent organic pollutants (POPs) as phthalates (Ps), non-phthalates (NPs), polychlorinated biphenyls (PCBs), and phenyl phosphates (PhePhs) in ambient total suspended particles (TSP) from the city of Dhahran, Saudi Arabia. The mass concentrations of TSP ranged from 88 ± 32 μg m−3 in winter to 350 ± 320 μg m−3 in summer. The total concentrations of these compounds varied from 337 ± 266 ng m−3 in summer to 469 ± 403 ng m−3 in winter. The major compounds were Ps (235 ± 199 ng m−3 in summer to 389 ± 335 ng m−3 in winter), PCBs (30.7 ± 19.3 ng m−3 in autumn to 65.6 ± 61.2 ng m−3 in summer), NPs (4.9 ± 2.3 ng m−3 in summer to 11.9 ± 12.5 ng m−3 in winter), and PhePhs (4.1 ± 4.0 ng m−3 in spring to 13.3 ± 3.2 ng m−3 in summer). The proportional fractions of these POPs relative to natural biogenic sources and petroleum-related emissions were extremely high ranging from 17% in winter to 47% in autumn. Significant correlations were found among these different POP groups and total concentrations, suggesting that they were from local sources. Principal component analysis indicated that Ps and NPs were from the same initial sources, and the PhePhs as well as PCBs were from different regional sources, where the latter were dependent on the TSP levels. In the long term, the elevated levels of these POPs in the TSP of these urban areas will affect human health by eventually developing a range of illnesses.

Hydrogen production via using excess electric energy of an off-grid hybrid solar/wind system based on a novel performance indicator

The present study aims to assess the potential of renewable energy resources in the Kingdom of Saudi Arabia (KSA) for electricity and hydrogen production. A hybrid renewable energy system which comprises of solar photovoltaic panels, wind turbine, batteries, electrolyzer, and a hydrogen-tank, is considered to meet the electrical requirements of a typical residential house in Dhahran city, eastern province, KSA, while providing the hydrogen fuel to a hydrogen driven vehicle. To determine the effective configuration of the hybrid renewable energy system, a computer code is developed and used for hourly based simulations incorporating real weather data and electric demand. The influence of the hydrogen vehicle refueling profile is investigated and optimization study is performed to minimize levelized cost of electricity (LCOE) and levelized cost of hydrogen while achieving specified relatability limits. To assess the performance of the hydrogen production sub-system, novel performance indicators are introduced, which include: deficiency in hydrogen supply, and loss of hydrogen supply probability (LHSP). The results showed that the electricity demand is fully covered when the optimum configuration of the hybrid system comprised 18 kW PV, 2 wind turbines and 14 batteries with LCOE of 0.593 $/kWh. Hydrogen production and hydrogen storage tank are sized based on the hybrid system excess energy generated after satisfying the electrical load for various hydrogen vehicle refueling scenarios. In this case, daily refueling scenario leads to the minimum possible hydrogen cost of 36.32 $/kg, and zero level of LHSP with 14 kg hydrogen storage. The environmental analysis shows that the developed system contributed in reduction of CO2 emission by 9.66 Tons per year.

Saccharomyces cerevisiae OS303 expression of an alkaline protease from a newly isolated Bacillus subtilis D9

The aim of this study was to produce high yield of a local bacterial alkaline protease in the yeast system because the scientific involvement of microorganisms in enzyme production is still not given enough attention in Saudi Arabia. Soil samples were collected from the rhizosphere of some desert plants in Saudi Arabia. Ninety-three alkaline protease producing bacterial isolates were recovered on skimmed-milk agar at pH 9.4 and 45°C for 48 hr. Isolate D9 obtained from the rhizosphere of Heliotropium digynum at Dhahran City was the most potent isolate in respect to enzyme productivity (184.6 U/ml). The full gene of alkaline protease was amplified and showed the expected size (1300 bp). Restriction enzymes analysis also verified the integrity of the PCR product. The sequence of the protease gene revealed an open reading frame of 1329 nt correspond to the full length of the protease gene of isolate D9 encoding a 443 aa protein. After ligation of the amplified gene by the TA cloning method, digestion with appropriate restriction enzymes confirmed the integrity of the cloned gene. The insert was prepared by two PCRs that were conducted with a pair of primers specifically designed for this purpose. The digested and purified cloning vector pRS426/GAL1p-207-Glu-MS was ligated with the insert then transformed into various strains of Saccharomyces cerevisiae via the electroporation method. Maximum protease expression was done by recombinant OS303 in galactose containing media (145.5 U/ml) with an approximately 2-fold increase when compared with the wild OS303 strain., this may be due to ability to activate gal operon.

Evaluation of Patient’s Satisfaction Level with the Provided Healthcare in Primary Healthcare Centers in Saudi Arabia

The aim of this study was to evaluate patient’s satisfaction at primary health centers PHCCs in (Khobar, Jeddah, Riyadh, Jubail, Dhahran, Hail, Majmah, Abha, Baha, and Makkah) located in Saudi Arabia. The review finding shows that the highest overall satisfaction in Baha city (84.16%) followed by Majmah city with (81.7%), and the lowest overall satisfaction was the score (2.44) out of a maximum of 5 for Jubail city and Jeddah (2.45). Dhahran, Hail, Abha, Makkah, Riyadh, and Khobar were scored different scores; (3.66), (3.60), (57.7%), (70.1%), (64.2%) and (3.76). Nursing staff play a vital role in the satisfaction of patients in primary healthcare centers, including education, care and counselling, which is why all nursing staff should be skilled in clinical skills, level of education and interpersonal skills The highest domain of satisfaction was for nursing performance, and their treatment were found to be high (90.1%), but the lowest score was for the explanation of the medical conditions by the nurses, which could be due to language barrier. Medical care, laboratory services, and pharmacological services are other factors that may impact patient satisfaction with primary health centers. There are significant differences between Abha city (57.7%) and Baha city (84.16%) in south province in their overall satisfaction with Patient’s Satisfaction in primary healthcare centers PHCCs. And between Riyadh city (64.2%) and Majmah city (82.0%) in the middle province. In the eastern province, overall satisfaction for three cities Khobar city (3.76), Jubail city (2.44), and Dhahran city (3.66). The western province, overall satisfaction for two cities, Makkah city (70.1%), and Jeddah city (2.45). One city for north province Hail city (3.60). For comparison, the highest overall satisfaction in this study was Baha city (84.16%) located in south province, and the lowest one was Jubail city with score (2.44) out of 5.

Factors Affecting the Household Income of Petty Traders During COVID-19 Pandemic in Dharan City

Petty trading is such a type of economic activity operating abundance of the low-earning population in new urbanizing developing countries like Nepal. The main aim of this study is to explore factors affecting the household income of petty traders during the COVID-19 Pandemic in Dhahran city. This investigation had used descriptive analysis, and Pearson correlation test to identify the relationship between dependent and independent variables. There were 48 petty traders conveniently selected for the convenient sampling to collect primary data by survey method. The data were analyzed through descriptive statistics by using SPSS. It is found a significant relationship between daily household income and marital status of petty traders. But there was no significant relationship between the daily household income and the size of the family, investment of capital of the petty traders. Similarly, the above results of this study suggest that this study is helpful to the planners and policymakers in Dharan city to formulate suitable policy and manage the micro-business sector including petty traders. And the government should create programs that preserve and establish the economic rights of petty traders and reduce the various complications and taxes which they usually impose on them. The study concluded that there is a significant difference between the household income of petty traders and the marital status of petty traders. Moreover, it established that there was no relationship between the household income and the family size, the investment of capital, and the income before COVID 19 of petty traders.

The Effect of Corruption and Anti-Corruption on Firm Performance

The research aimed to investigate the effects of corruption and anti-corruption on firm performance. The data of the research was collected from participants who work in a private international school group in Dhahran city in Saudi Arabia, this research was applied to a sample of 200 employees. The result of the study has indicated that there is a significant low relationship between corruptions and firm performance, the results also indicated that there was a significant strong relationship between anti-corruption and firm performance. and the results showed that there is no significant effect of corruption on Firm performance while there is a strong significant effect of ant-corruption on firm performance. The research has recommended that managers and officials should invest more time in anti-corruption awareness, and try to control corrupted behaviors, finally implement an effective system to help both managers and employees avoid any related corruption behaviors. يهدف البحث إلى دراسة تأثير الفساد ومکافحة الفساد على أداء الشرکات. تم جمع بيانات البحث من مشارکين يعملون في مجموعة مدارس دولية خاصة في مدينة الظهران بالمملکة العربية السعودية، تم تطبيق هذا البحث على عينة قدرها 200 موظفا. أشارت نتائج الدراسة إلى وجود علاقة معنوية ضعيفة بين الفساد وأداء الشرکات، کما أشارت النتائج إلى وجود علاقة معنوية قوية بين مکافحة الفساد وأداء الشرکات، کما بينت النتائج وجود عدم وجود تأثير معنوى للفساد على أداء الشرکات، بينما يوجد تأثير معنوى قوى لمکافحة الفساد على أداء الشرکات محل الدراسة. وأخيرا أوصى البحث بضرورة استثمار المديرين والمسؤولين مزيدا من الوقت في التوعية بمکافحة الفساد ، ومحاولة السيطرة على السلوکيات الفاسدة ، وتبنى نظام فعال لمساعدة کل من المديرين والموظفين على تجنب أي سلوکيات لها صلة بالفساد.

Optimizing the Solar PV Tilt Angle to Maximize the Power Output: A Case Study for Saudi Arabia

Estimation of solar radiation distribution is crucial for the performance, design, and economic evaluations of solar panels and/or collector systems operating under various climatic conditions, tilt angles, and geographic locations. A comprehensive study involving the combined effect of tilt angle as well as ambient temperature for maximizing the PV array power output was performed. At first, we present a comparison between different isotropic and anisotropic models showing that the anisotropic model gains 5% more energy than the isotropic one. We report monthly and yearly optimum tilts derived from the anisotropic model. Utilizing the optimum tilt derived from the selected anisotropic model, a case study of a mono-crystalline silicon PV array with 2.76 kWp of the rated power is carried out to evaluate the PV performance in five cities of the Kingdom of Saudi Arabia. The results show that the estimated yearly optimum tilt angle is close to the latitude of the studied cities. For the city of Dhahran, a gain of 4.2% power generation is achieved at ambient temperature through monthly adjustment of the PV module instead of yearly adjustment. The estimated yearly tilt angles are as follow: 27.3° for Dhahran, 26.0° for Riyadh, 22.7° for Jeddah, 32.7° for Arar, and 20.1° for Abha. Although Riyadh and Arar receive the same annual average GHI of 6.0 kW/m2, the yearly average PV power output is ~7.1% higher for Arar (1.50kW) compared with Riyadh (1.40 kW). This is mainly attributed to the fact that Riyadh has a higher annual average ambient temperature of 29°C compared with 23°C for Arar. Thus, in addition to panel orientation, the ambient temperature was found to have a significant impact on the performance of the PV system and should be taken into consideration when designing the system.

On the Potential Impacts of Smart Traffic Control for Delay, Fuel Energy Consumption, and Emissions: An NSGA-II-Based Optimization Case Study from Dhahran, Saudi Arabia

Intelligent traffic control at urban intersections is vital to ensure efficient and sustainable traffic operations. Urban road intersections are hotspots of congestion and traffic accidents. Poor traffic management at these locations could cause numerous issues, such as longer travel time, low travel speed, long vehicle queues, delays, increased fuel consumption, and environmental emissions, and so forth. Previous studies have shown that the mentioned traffic performance measures or measures of effectiveness (MOEs) could be significantly improved by adopting intelligent traffic control protocols. The majority of studies in this regard have focused on mono or bi-objective optimization with homogenous and lane-based traffic conditions. However, decision-makers often have to deal with multiple conflicting objectives to find an optimal solution under heterogeneous stochastic traffic conditions. Therefore, it is essential to determine the optimum decision plan that offers the least conflict among several objectives. Hence, the current study aimed to develop a multi-objective intelligent traffic control protocol based on the non-dominated sorting genetic algorithm II (NSGA-II) at isolated signalized intersections in the city of Dhahran, Kingdom of Saudi Arabia. The MOEs (optimization objectives) that were considered included average vehicle delay, the total number of vehicle stops, average fuel consumption, and vehicular emissions. NSGA-II simulations were run with different initial populations. The study results showed that the proposed method was effective in optimizing considered performance measures along the optimal Pareto front. MOEs were improved in the range of 16% to 23% compared to existing conditions. To assess the efficacy of the proposed approach, an optimization analysis was performed using a Synchro traffic light simulation and optimization tool. Although the Synchro optimization resulted in a relatively lower signal timing plan than NSGA-II, the proposed algorithm outperformed the Synchro optimization results in terms of percentage reduction in MOE values.

Analysis of Potassium-40 (40K) in Soil Samples from Dhahran City, Saudi Arabia, Using Gamma Spectrometer

Analysis of Potassium-40 (40K) in Soil Samples from Dhahran City, Saudi Arabia, Using Gamma Spectrometer

Intelligent Intersection Control for Delay Optimization: Using Meta-Heuristic Search Algorithms

Traffic signal control is an integral component of an intelligent transportation system (ITS) that play a vital role in alleviating traffic congestion. Poor traffic management and inefficient operations at signalized intersections cause numerous problems as excessive vehicle delays, increased fuel consumption, and vehicular emissions. Operational performance at signalized intersections could be significantly enhanced by optimizing phasing and signal timing plans using intelligent traffic control methods. Previous studies in this regard have mostly focused on lane-based homogenous traffic conditions. However, traffic patterns are usually non-linear and highly stochastic, particularly during rush hours, which limits the adoption of such methods. Hence, this study aims to develop metaheuristic-based methods for intelligent traffic control at isolated signalized intersections, in the city of Dhahran, Saudi Arabia. Genetic algorithm (GA) and differential evolution (DE) were employed to enhance the intersection’s level of service (LOS) by optimizing the signal timings plan. Average vehicle delay through the intersection was selected as the primary performance index and algorithms objective function. The study results indicated that both GA and DE produced a systematic signal timings plan and significantly reduced travel time delay ranging from 15 to 35% compared to existing conditions. Although DE converged much faster to the objective function, GA outperforms DE in terms of solution quality i.e., minimum vehicle delay. To validate the performance of proposed methods, cycle length-delay curves from GA and DE were compared with optimization outputs from TRANSYT 7F, a state-of-the-art traffic signal simulation, and optimization tool. Validation results demonstrated the adequacy and robustness of proposed methods.

Examining the Walking Accessibility, Willingness, and Travel Conditions of Residents in Saudi Cities.

Rapid urban expansion and population growth in Saudi cities over the past four decades have increased vehicular accidents and traffic congestion and have impacted the daily walking conditions of the residents. Walking has various health and environmental benefits. In North American and European countries, three factors have been found to motivate a resident to walk within their community: their accessibility to community social and business facilities, their perception and willingness, and the safety conditions of the roads and sidewalks within their community for walking. This study examined these factors and their role in the walking habits of the residents in the neighborhoods of Doha and Dana districts in Saudi Arabia’s eastern city of Dhahran. Data were collected through field observations and by randomly sampling and interviewing 200 residents. Geographic Information Systems (GIS) and SPSS statistical software were used for data analysis. The results show that most of the community facilities are randomly placed in the districts. Mosques are the closest facility to each resident with an average accessibility distance of 242m. Almost 43% of the respondents prefer daily walking while the rest are hesitant due to hot weather during summer and narrow and poorly designed sidewalks. The sidewalks were also found to be blocked by trees, street signals, and illegally parked vehicles. Future studies should explore the accessibility to facilities, willingness, climate, and health conditions of the residents, and the road and sidewalk conditions for walking in other cities of the Kingdom.

Estimation of solar radiation on PV panel surface with optimum tilt angle using vortex search algorithm

The amount of solar energy incidence on a photovoltaic (PV) panel depends on the PV tilt angles with respect to the horizon. It is thus crucial to investigate the optimum tilt angles to maximise the efficiency of PV panels and at the same time to increase the performance of solar energy systems. The objective of this study is to estimate the optimum tilt angle for PV panels in order to collect the maximum solar radiation for the city of Dhahran in Saudi Arabia. A newly developed optimisation algorithm called the vortex search algorithm is used to estimate the solar radiation on the tilted surface. Moreover, one year can be divided into different periods in the proposed approach, and the optimum angle can be obtained for each one of these periods separately. The horizontal solar data (i.e. direct, diffuse and global solar radiation) is used to estimate the optimum tilt angle. The results demonstrate that the solar radiation estimated using the optimum tilt angle is maximised compared with the one estimated on a horizontal surface.

استخدام إستراتيجية الجدول الذاتي (K.W.L) لتدريس مقرر الحاسب الآلي لتنمية التحصيل الدراسي لدى طلاب الصف الأول الثانوي بمدينة الظهران بالمملكة العربية السعودية

هدف البحث الحالي إلى التعرف على استخدام إستراتيجية الجدول الذاتي (K.W.L) لتدريس مقرر الحاسب الآلي لتنمية التحصيل الدراسي لدى طلاب الصف الأول الثانوي بمدينة الظهران بالمملکة العربية السعودية ، ولتحقيق هذا الهدف تم إختيار وحدة الوسائط المتعددة مـن کتـاب الحاسب الالي المقرر لطلاب الصف الاول الثانوي وتم إعدادها تفصيليا ، وفي ضوء ما سبق تم إعداد اختبار تحصيلي من إعداد الباحث ، ولتحقيق أهداف البحث ، استخدم المنهج شبه التجريبي حيث طبق البحث على مجموعة مؤلفة من (27) طالبا موزعين على مجموعتين الأول ضابطة (14) طالبا درست بالطريقة المعتادة ، والثانية تجريبية (13) طالبا درست باستراتيجية الجدول الذاتي K.W.L، أظهرت نتائج تحليل علامات الطلاب على اختباري التحصيل في التطبيقين القبلي والبعدي باستخدام اختبار تحليل التباين المصاحب: وجود فروق ذات دلالة إحصائية بين متوسطي تحصيل الطلاب على اختبار التحصيلي وفقا لمتغير المجموعة، لصالح طلبة المجموعة التجريبية . The current study aimed to measure the effectiveness of using self-table K.W.L stratege achievement in computer course for the first Graders of a high school in Dhahran City in the kingdom of Saudi Arabia . The programming unit was chosen to achieve this objective on the students of Grade one at a high school. This unit was prepared in details. In light of what was done, the achievement test was designed by a researcher. The Semi-Experimental Method was used to accomplish the objectives of the study. The study was applied on a sample of ( 27 ) male students which was divided into two groups; the first was Controlled Group ( 14 ) students taught in traditional method. The second Experimental Group ( 13 ) was taught through the strategy of self-table K.W.L .The results of the analysis showed signs of students on the two achievement tests on the post and pre-application via variety analysis test. There are clear statistic differences among average achievement of the students according to the variable for the Experimental Group.

Effectiveness of the learning strategy using the concept maps on students' achievement in the computer material for the first secondary school in Dhahran city, Saudi Arabia: فاعلية استراتيجية التعلم باستخدام خرائط المفاهيم على تحصيل الطلاب في مادة الحاسب الآلي للصف الأول الثانوي بمدينة الظهران بالمملكة العربية السعودية

The current study aimed to identify the measurement of the effectiveness of the learning strategy using the concept maps on students' achievement in computer science for the first secondary grade in Dhahran City, Saudi Arabia. To achieve this goal, the programming unit was selected from the computer book In order to achieve the objectives of the study, the semi-experimental method was used. The study was applied to a sample of 33 students divided into two groups: the first is an officer (16) students The results of the analysis of the students 'scores on the achievement tests in the tribal and remote applications were examined using the analysis of the accompanying variance: There were statistically significant differences between the students' average achievement on the achievement test according to the group variable, For the students of the experimental group, and there were statistically significant differences between the average marks of the students on the achievement test according to the variable of the group, in favor of students In the light of the results, the researchers recommended a set of recommendations to activate the use of conceptual maps in teaching.

The Effects of an Integrated Curriculum on Student Achievement in Saudi Arabia

This study examined the effects of an integrated mathematics and science curriculum with life-skills applications on academic achievement in a Saudi Arabian elementary school. An integrated unit was developed covering the grade 5 ‘sound and light’ science unit and the ‘perimeter, area, and size’ mathematics unit, using practical applications activities connected to the students’ everyday lives. The study involved treatment (n = 36) and comparison (n = 41) groups of grade 5 students (females) enrolled in a private school in Dhahran City. The comparison group was instructed using a conventional approach involving separate science and mathematics units, while the treatment group was instructed using the integrated unit. Two achievement tests for the target science and mathematics units were developed and used in the pretest-posttest design to verify the equivalence of the treatment and comparison groups before conducting the study, and to compare the achievement results after implementing the conventional and treatment units. The study found statistically significant differences favouring the treatment group on the achievement posttest (effect sizes were 0.44 for science and 0.49 for mathematics). These large effect sizes indicated the positive impact of using the proposed strategy of curriculum integration to evaluate the teaching program to see if the goal of improved achievement was actually realised.