Journal of King Abdulaziz University: Engineering Sciences

An Oligopoly Market Analysis in the Food and Beverage Sector Using Game Theory

Ammar Alqahtani, Anas A. Makki — Sat, 02 Dec 2023 00:00:00 +0000

Food and beverage production firms are socially active workplaces by their very nature. They function in an oligopoly market environment with their competitors. Conflicting interests of competitors create tradeoff game situations that impact many business decisions. The purpose of this paper is to conduct an oligopoly market analysis in the food and beverage sector using game theory. Data from two leading competing brands in the industry were collected for analysis. Five social interaction-related decisions were the focus of this study: marketing campaigns, price war, investment in R&D, the introduction of a new product, and a new policy. The designed games were based on the Prisoner's Dilemma, Deadlock, and Extensive-Form game models. Games, players, strategies (actions), assumptions (payoffs), representations, analysis, and results are addressed in a series of phases for each of the five studied decisions. Implications of this study include assisting decision-makers in the food and beverage industry in developing reactive and proactive strategies for competitor actions and maintaining competitive advantage.

Computer-Aided Detection System of MRI brain tumor images

Mohammed Bamaleibd — Sat, 02 Dec 2023 00:00:00 +0000

Computer-Aided Detection (CAD) recognizes tumors or lesions in medical imaging or distinguishes between normal and abnormal images. The purpose of this paper is designing a CAD system that will automatically detect brain tumors and classify the brain images in terms of normality and abnormality. The proposed CAD system passed through seven essential processes which are data collection, preprocessing and enhancement, segmentation, feature extraction, feature selection, classification, and performance assessment, respectively. The database includes 280 normal and abnormal brain MRI images. Segmentation process in this paper was an independent process aims to aid in the extraction of the region of interest (ROI). ROIs were cropped from the original images around the center of the tumor region which was specified after segmentation. The overall results of the proposed CAD system depended on the performance of eight different types of SVM classifiers and KNN classifiers. SVM of radial basis function and linear types, as well as KNN of 3 and 5 neighbors, obtained perfect results with 100% in all performance assessment metrics. The remainder of the classifiers achieved high accuracy, where SVM of polynomial type with KNN of 1 and 2 neighbors achieved the same result with 97.62% a little less than KNN of 4 neighbors which achieved 98.81%. The proposed CAD system provided results more accurate and precise compared with other studies.

Occupational hazards and associated risks in university laboratories: A case study of mining engineering department laboratory

Ali Y. Al-Bakri, Haitham M. Ahmed, Mohammed Hefni — Sat, 02 Dec 2023 00:00:00 +0000

Laboratories occupy a prominent role in the academic field through research, experimentation, and promoting educational practices for students. On the other hand, university laboratories' work is accompanied by some risks that may negatively impact the safety of researchers, students, technical staff, and visitors. This paper, through the mining engineering lab, carried out a risk assessment from an occupational safety perspective. The conducted risk assessment aimed to identify the equipment's potential induced hazards, review existing controls, minimize the associated risks, prioritize them, and then create a safe work area with additional control measures. The study covered sixteen significant pieces of machines in mineral processing and rock mechanics labs. Obtained results indicated around seventy-two identified hazards. A high-risforscale is assessed in the equipment of Electromagnetic and Magnetic Separators. Both required strict additional control measures as recommended. In addition, outcomes showed some medium-risk scale might be related to operating the manual drilling equipment and the crusher. The acceptable levels of risk scale have been achieved in most laboratory equipment; however, some additional control measures are suggested to reach the minimum levels of risks. The literature review revealed a significant lack of research conducted to examine the university laboratories' risk except for labs used in the chemical studies. Therefore, more studies are strongly recommended to investigate the occupational hazards and associated risks in university laboratories.

Comprehensive Investigation of the Side-gate Effect on the RF Small-signal Equivalent Elements of AlGaN/GaN High-Electron-Mobility Transistor on a Silicon Substrate

Sami Alghamdi — Sat, 02 Dec 2023 00:00:00 +0000

The side-gate effect on the radio frequency (RF) small-signal equivalent elements of an AlGaN/GaN HEMT on a high-resistivity silicon substrate was comprehensively studied. The side-gate bias was found to have a significant impact on the direct-current (DC) and small-signal performance of the device through the buffer layer. Gate and drain bias dependent small-signal equivalent circuit parameters were extracted at different side-gate biases, and the physical mechanism was investigated and analyzed. These findings suggest that the side-gate effects should be taken into account when monolithic microwave integrated circuits are designed based on GaN-on-Si HEMTs.

Standardization of Chargers for Portable Electronic Devices in the Saudi Market

Hani Aldhubaib, Muhannad A. Abu-Hashem, Mohd Khaled Shambour — Sat, 02 Dec 2023 00:00:00 +0000

In recent years, portable devices such as mobile phones, tablets, digital cameras, headphones, and portable speakers have been used more commonly. These devices usually come with a particular type of charger that may or may not be suitable for use with other devices. The incompatibility issue of chargers has garnered much attention worldwide in the last few years, including in Saudi Arabia. The main points of investigation are the environmental, economic, and social impacts of having many types of chargers for portable electronic devices. Due to the massive size of the electronic market in Saudi Arabia, this paper aims to survey consumers’ opinions about the current situation of chargers and assess the potential impact of standardizing chargers in the Saudi market. The descriptive analytics approach is used in this study through an electronic questionnaire. The study received 1,527 responses from 13 provinces within Saudi Arabia. The results demonstrate serious challenges associated with electronic device chargers and the significant need to standardize them. The environmental, social, and economic benefits of this standardization are outlined. The findings of this paper recommend that policymakers in Saudi Arabia embrace the standardization of chargers for all portable electronic devices.