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1.
Remote Sensing ; 15(3), 2023.
Article in English | Scopus | ID: covidwho-2268826

ABSTRACT

Agricultural intensification has resulted in the depletion of groundwater resources in many regions of the world. A prime example is Saudi Arabia, which witnessed dramatic agricultural expansion since the 1970s. To explore the influence of policy interventions aimed to better manage water resources, accurate information on the changes in the number and acreage of center-pivot fields is required. To quantify these metrics, we apply a hybrid machine learning framework, consisting of Density-Based Spatial Clustering of Applications with Noise, Convolutional Neural Networks, and Spectral Clustering, to the annual maximum Normalized Differential Vegetation Index maps obtained from Landsat imagery collected between 1990 to 2021. When evaluated against more than 28,000 manually delineated fields, the approach demonstrated producer's accuracies ranging from 83.7% to 94.8% and user's accuracies ranging from 90.2% to 97.9%. The coefficient of determination ((Formula presented.)) between framework-delineated and manually delineated fields was higher than 0.97. Nationally, we found that most fields pre-dated 1990 (covering 8841 km (Formula presented.) in that year) and were primarily located within the central regions covering Hail, Qassim, Riyadh, and Wadi ad-Dawasir. A small decreasing trend in field acreage was observed for the period 1990–2010. However, by 2015, the acreage had increased to approximately 33,000 fields covering 9310 km (Formula presented.). While a maximum extent was achieved in 2016, recent decreases have seen levels return to pre-1990 levels. The gradual decrease between 1990 to 2010 was related to policy initiatives designed to phase-out wheat, while increases between 2010 to 2015 were linked to fodder crop expansion. There is evidence of an agricultural uptick starting in 2021, which is likely in response to global influences such as the COVID-19 pandemic or the conflict in Ukraine. Overall, this work offers the first detailed assessment of long-term agricultural development in Saudi Arabia, and provides important insights related to production metrics such as crop types, crop water consumption, and crop phenology and the overarching impacts of agricultural policy interventions. © 2023 by the authors.

2.
Energy Exploration and Exploitation ; 2023.
Article in English | Scopus | ID: covidwho-2248621

ABSTRACT

Energy consumption is one of the most important variables that have an impact on the environment. One of the nations in the world with the highest per capita electrical energy usage is the Kingdom of Saudi Arabia. Many attempts are being made in Kingdom of Saudi Arabia to lower energy consumption and electricity consumption to achieve sustainability. In this work, the data on the energy consumption of two mosques in Hail City were analyzed, and the opportunities for energy conservation and the use of solar energy were studied to make mosques sustainable. Annual energy use intensity was determined to be 100 and 121 kWh/m2 for the Al-Khashil and Al-Jamil mosques, respectively. While Al-Khashil's mosque envelope is insulated, energy efficiency measures implemented to the walls of Al-Jamil's mosque resulted in reductions in energy consumption of 27%, 13%, and 6%, respectively. The most effective energy efficiency option is a heating, ventilation, and air conditioning system with a high energy efficiency ratio, which can reduce cooling demand by more than 30%. If the condition of Saudi Building Code 601 is met, then it has the potential to cut energy usage by 35.4% and 63.3% for Al-Khashil and Al-Jamil, respectively. Due to coronavirus disease 2019, Al-Khashil's electricity usage was reduced by 58,737 kWh, or 39.9%, in 2020 compared to 2019. When using data from RETScreen and ATLAS, there were inconsistencies of up to 28%, but for DesignBuilder, the findings were the closest to the billing data. The mosques Al-Khashil and Al-Jamil have a combined yearly photovoltaic energy output from the suggested systems of around 135.93 MWh and 33.98 MWh, respectively. For the mosques, Al-Khashil and Al-Jamil, the yearly yield factor and capacity factor were both 1887.9 kWh/kWp/year and 21.9%, respectively. The annual greenhouse gas emission reductions from photovoltaic systems for Al-Khashil and Al-Jamil were 102.9 tCO2 and 25.72 tCO2, respectively. Concerning economics, the following results were obtained: The levelized cost of energy of photovoltaic systems is 0.0901 SR/kWh (0.024 $/kWh);the net present value and internal rate of return for photovoltaic systems are not suitable as a result of the current prices and the system applied in the Kingdom of Saudi Arabia. If the electricity produced from photovoltaic systems is injected into the grid at a rate of 0.32 SR/kWh, which is comparable to the SEC tariff for the mosque or government sector, then the simple payback time is 5.14 years. © The Author(s) 2023.

3.
4th International Conference on Computer Science and Technologies in Education, CSTE 2022 ; : 27-30, 2022.
Article in English | Scopus | ID: covidwho-2191701

ABSTRACT

In early 2020, COVID-19 appeared and widely spread worldwide. It affected all vital sectors, including commercial activities and education. Most governments decided to temporarily close educational institutions, including schools and universities. Developed countries with adequate learning-management systems moved to the online teaching mode. Hence, the sudden transition from the traditional to online teaching mode has impacted learning outcomes. The ultimate goal of this paper is to develop a method for evaluating the experience of teaching online during epidemics. More precisely, it assesses the teaching of programming language courses in the computer science and engineering college at the University of Hail. It statistically measures the courses' learning outcomes in the online mode compared to the traditional mode. Perhaps surprisingly, the difference was not significant, which shed light on the positive side of the crisis. According to the obtained results, the experience of teaching online during an epidemic has led us to investigate the opportunities of using online teaching, especially for programming language courses. This highlighted opportunities for using online platforms as supportive teaching tools or even merging them with traditional teaching approaches at times when attending classes on campus is impossible. Finally, to ensure best practices, the author recommended some guidelines to follow. © 2022 IEEE.

4.
53rd Annual ACM Technical Symposium on Computer Science Education, SIGCSE 2022 ; : 1043-1044, 2022.
Article in English | Scopus | ID: covidwho-1789000

ABSTRACT

This panel is the evolution of a Technology that Educators of Computing Hail (TECH) Birds of a Feather session held at SIGCSE for seven years, grew into popular panels for many years, and served as a springboard for a regular column in ACM Inroads. It will provide a chance for seasoned middle school, high school, and university educators to showcase the technologies they can't live without, what problems they solve, and how to use them. This year, we asked our panelists to highlight any technology in particular that helped them survive (and possibly even thrive!) during their remote teaching. © 2022 Owner/Author.

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