Chlorophyll-A Estimation from Remotely Sensed Data

The science of remote sensing is commonly defined as method that employs electromagnetic energy to detect, record, and measure characteristics of a target. Concentrations of chlorophyll-a in water have been estimated from the spectral distribution of back-scattered light, related to reflectance. Remote sensing in general has been used much more extensively for oceans than for inland waters. Advanced image processing techniques introduced and applied using Landsat Thematic Mapper data acquired on February 22, 1 994 over the indicated region of South China Sea. The objective of the study was to calculate the chlorophyll-a concentration along Kuala Terengganu. The method was carried out to calculate the chlorophyll-a concentration in the study area that is, digital image processing which include preprocessing, display, enhancement, information extraction, and algorithm to calculate the estimated chlorophyll-a. Results of the regression analysis of DNs against referenced chlorophyll-a was used to calculate the actual chlorophyll-a concentration (calculated chlorophyll-a) of Landsat TM bands 1, 2, and 3. The results show that the chlorophyll-a concentrations in the study area are significantly correlated with band 1, 2, and 3. The lower chlorophyll-a concentration with levels (0.031-0.019) mg/m3, the higher chlorophyll-a concentration with levels (0.404-0.391) mg/m3. Finally, band 2 was the best in terms of all the parameters evaluated. In conclusion, remote sensing is an important technology for measuring chlorophyll-a concentration in the coastal water of South China Sea. From the result, TM sensor has been found a useful tool for studying chlorophyll-a concentration

Developing a Virtual Educational Environment Based on Distance Learning Needs to Enhance Creative Teaching Abilities for Science Teachers In the city of Ha'il

The objective of this study was to develop a customized virtual learning platform specifically designed for distance education with the goal of improving the pedagogical abilities of science instructors at Hail University. The research used a descriptive analytical method, including expert assessments of the requirements for remote education and the necessary teaching abilities. A survey was conducted among 120 science teachers in Hail, and it was found that there is a significant need and value for training in several aspects of innovative teaching. The results emphasized substantial requirements in five crucial domains: innovative instruction as well as competencies associated with fluency, adaptability, and ingenuity. The virtual learning environment created for Hail Science instructors had a comprehensive evaluation by training program professionals using a unique assessment method. This evaluation ensured that the design of the environment included both technological and pedagogical criteria

New Techniques for Disconnector Switching VFT Mitigation in GIS

Switching operations in a Gas Insulated Substations (GIS) generate very fast transient over voltages (VFTO) which are dangerous for the transformer and the system insulation because of their short rise time. Under special circumstances the overvoltages can arise close to the transformer Basic Insulation Level (BIL). The reduction of VFTO amplitudes is considered main challenges. Therefore, VFTO in the 220 kV Wadi-Hoff GIS is analyzed and the worst case for disconnector switching is predicted using EMTP/ATP in this paper. VFTO mitigation techniques are studied in this work. Furthermore, proposed techniques are presented for mitigating the VFTO. The proposed techniques can be used by the maintenance engineers, transformer designers, and GIS insulation manufactures. The results show that the proposed techniques highly reduce the VFTO in a simple manner.DOI:http://dx.doi.org/10.11591/ijece.v4i2.518

Universal Data Logger System for Environmental Monitoring Applications

Collecting huge amount of data in long time acquisition systems like in environmental monitoring, there is a need to collect and save data over time for further use or analysis. A data logger is an electronic device that records data over time or in a relation to location either with a built-in instrument, sensor or via an external instruments and sensor. In this paper, a data logger system is designed to use as a stand-alone or computer based device. When used as a standalone system, all data acquired are saved in SD memory card, which must be copied and erased periodically depending on the memory size. When used as computer based device, all the data sent to the computer via the serial port and stored automatically in achieved files. The limit of those files size only restricted by the capacity of the disk. The data logger is designed using an Arduino UNO board and LabView software, and it has the flexibility to set it up for different user options. With this system, the user could be able to record and read back sensory data to or from existing files, or in automatically generated files and plot these readings in a graph. Also, the user have the ability to choose the periodic time at which a sample record in a file in term of seconds, minutes or hours. The system designed to monitor and record a single channel data, but it could be adapted to monitor more than one channel

Effect of Functionally Graded Material of Disc Spacer with Presence of Multi-Contaminating Particles on Electric Field inside Gas Insulated Bus Duct

Solid insulators play a crucial role of electrical insulation in gas insulated power equipment. In order to improve the insulation performance of the solid insulators, two technical points should be considered, the first is the improvement of the insulation performance and the second is the control of the electric field distribution in and around the solid insulating spacers. Practically the insulation performance around the spacer can be improved by various techniques, such as; controlling the spacer shape, adding shield electrodes for electric field relaxation, the introduction of an embedded electrode, etc. These techniques lead to a more complicated structure of the equipment and increase the manufacturing cost. Thus, it is necessary to propose a new concept on solid spacers with keeping their simple structure and configuration. In this paper, a functionally graded material (FGM) is proposed to minimize the electric field distribution around the spacer, specially, on triple junction point, which was one of the important factors dominating a long-term insulating property of solid delectric. Finite Element Method (FEM) has been used throughout this work, for its favorable accuracy, to calculate the electric field distribution inside the bus duct. The Electric field distribution around earthed particle contamination which adhered to uniform and FGM of disc-spacer is presented. The effect of distance between particle and spacer on the electric field values is investigated. The effect of hemi-spherical radius and length of particle on maximum electric field at triple junction point is also discussed. Electric field relaxation effect (EFGM/Euniform) by introduction of the U-shape FGM spacer is also presented. The electric field distribution along the surface of FGM of disc spacer with presence of multi-contaminating particles at various positions is presented.DOI:http://dx.doi.org/10.11591/ijece.v3i6.435

Effect of Coating of Earthed Enclosure and Multi-Contaminating Particles on Breakdown Voltage inside Gas Insulated Bus Duct

Metallic particle contamination is one of the areas of insulation design that are considered critical. This paper demonstrates the control of metallic particles in gas insulated bus duct (GIBD) by using dielectric coating on the inside surface of the outer enclosure of a coaxial electrode system. Several models of GIBD with single and multi-contaminating particles will be studied. In this paper, the Finite Elements Method (FEM) is used to evaluate the electric field distribution on and around single and multi-contaminating wire particles which in contact with dielectric coating of earthed enclosure inside GIBD. The effect of changing the length and the radius of middle particle for multi-contaminating particles on the electric field values are studied. Breakdown Voltage calculations for gas mixtures with single and multi-contaminating wire particles are studied. The effects of gas pressure on the breakdown voltage for various fractional concentrations of SF6-gas mixtures with and without particle contamination and also with and without coating of earthed enclosure are studied. The optimum gas mixture which gives higher dielectric strength with lower cost is also determined. The effect of coating thickness of earthed enclosure on the breakdown voltage for various fractional concentrations of SF6-gas mixtures is also studied. Finally, the effect of length and hemi-spherical radius of multi-contaminating particles on the breakdown voltage with various SF6-gas mixtures and varying gas pressure one time and another time with fixed pressure are studied.DOI:http://dx.doi.org/10.11591/ijece.v4i4.569

Print-Media Beyond Academia

Printmaking as an art discipline has been taught in different visual and fine arts academic programs around the world for hundreds of years. Thousands of printmaking students have graduated from different Art schools hoping to continue pursuing and fulfilling their artistic aspiration and passion, however, only handful of those, mostly university-affiliated, manage to do so. Obviously many factors may contribute to that phenomenon, however; the unavailability of printmaking equipment, which exist mainly in the educational institutions, the high cost of printmaking materials and the absences of the promotion and marketing of printmaking art, may be the most conspicuous factors that drive printmaking artists to quit. This research aims to explore new approaches that enable printmaking students to continue working in the real world after leaving the confinement of their educational institution and to investigate different possible solutions that may allow Printmaking Art and Artists to survive outside the Academic institution. Keywords: Print-Media, Printmaking Art, Printmaking Art Education, Experimental Printmaking, Printmaking Co-Ops

The Aesthetic Function of Arabic Calligraphy in Designing Dynamic Brand Identities

Arabic calligraphy can be located in its date on set of external references, starting from submission through religion trying to achieve aesthetic elements abstracted from the location itself. Therefore, the Arabic calligraphy had stated some artistic rules and regulations governing its direction. It remained as it is three centuries before and when the appearance of contemporary technologies and the exchange of artistic and social taste by the factors, which was influence by civilization. The calligraphy has taken new forms where assessors tried to adapt it aiming at achieving the new goals. Calligraphy have entered the work of prevalent logos as an effective element, trying for an attempt to achieve an identity in the logos taken from its Western centrality, and an attempt to invest the artistic power of calligraphy in designing dynamic identities.The aims of this research were formed to assess the use of aesthetic function of Arabic calligraphy in designing dynamic identities. However, now day’s dynamic identities are used in different types of new media platform, and by assessing these aesthetics, artists and designers has to be able to create a dynamic identity with a set of guidelines for the future reference. Keywords: Arabic Calligraphy, Dynamic Identities, Cross- media

Letterer Siwe Disease (LSD): A Case Report

Background: Letterer–Siwe Disease (LSD) is one of the variants of Langerhans cell histiocytosis (LCH), which is considered as a rare disease that affects many systems in the body; it is characterized by monoclonal migration and proliferation of specific dendritic cells. The disease affects the bones and skin primarily, but can involveother organs as well, or appear as a multi-system disease leading to different clinical manifestations and eventually death. Summary: The authors present a case report of LSD in a two-year-old child from western Sudan, Messeria tribe, who is presented with one and a half-month history of fever, cutaneous ulcers, purprae,scaly crusted scalp, and pallor. His full blood count showed very low Hb with marked reduction of platelets. TWBC was normal. US showed hepatosplenomegaly with lymphadenopathy. A suspicion of sickle cell anemia and leukemia was suggested. He received treatment in his area in the form of antibiotics, skin care, blood transfusion and platelets aggregate without improvement. Patient was referred to Khartoum for further investigations and management. On presentation, a diagnosis of histiocytosis x was suggested depending on the clinical presentation of a general ill health in a child with purpurae, skin ulcers, and a scaly crusted scalp. A skin biopsy, bone marrow aspirate, and a skull x-ray were requested. Bone marrow aspiration showed hyper cellular BM with marked hemophagocytosis. Patient was admitted in a pediatric ward for further general investigations and blood transfusion, but he passed few days later before starting chemotherapy. Usually this is the prognosis of this rare and fatal aggressive form of histiocytosis x. Conclusion: A sick child with fever, anemia, hepatosplenomegaly, scaly scalp, and skin lesions should be investigated for LSD

Medical students' satisfaction regarding blended learning during COVID-19 pandemic

Background: The realization of the profession’s role in both of global and personal concept affected the self-identification among 2020 medical students. COVID-19 pandemic can hinder, accelerate, or change medical students’ professional identity formation. Objective: To assess the level of satisfaction about blended learning among undergraduate medical students at Zagazig University and to determine challenges, which face the medical students during blended learning education in Faculty of Medicine. Patients and Methods: This cross-sectional study was performed during the period from September 2020 to July 2021 at Zagazig University, Egypt. This research included 277 undergraduate medical students. Results: The current study reported that interaction satisfaction score ranged from 18 to 53 with median 37 and 53.1% of students reported high satisfaction with interaction domain. There was statistically significant correlation between total satisfaction score and both age and technology barrier. There was statistically non-significant correlation between total satisfaction score and communication barrier. Conclusion: The results show that the majority of our sample students were highly satisfied with blended learning and reported low barriers to e-learning. Students still prefer face-to-face courses despite their satisfaction with their grades and performance in blended learning courses