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New Agile Matrix Antenna for Nano-satellite Telemetry Using Bimodal Pattern Reconfiguration
Ali Siblini,
Eric Arnaud,
Anthony Bellion,
Hussein Abou Taam,
Bernard Jecko
Issue:
Volume 5, Issue 1, March 2020
Pages:
1-19
Received:
15 October 2019
Accepted:
13 November 2019
Published:
21 January 2020
Abstract: This review deals with the design of a new reconfigurable beam antenna used to improve the efficiency of spatial telemetry links on Nano-Satellite. Advances in this domain show the needs to serve some applications with special electromagnetic beams and polarization patterns especially from LEO and MEO Space-Earth links. The RF front end must be capable to switch from high gain directive pattern to special pattern called Isoflux where the gain must be concentrated at high elevation angles with another challenge also the circular polarization. The content is a part of the CNES project that serves for multimode beam forming applications. This agile beam antenna is not built on the well-known array concept: AESA stands for Agile Electronically Scanned Array but using a new approach called ARMA standing for Agile Radiating Matrix Antenna. Contributions will show the small size elementary antenna of ARMA called Pixel, the polarization circuits that fit the challenges of the Nano-Satellite dimensions, the enhancement in the circular polarization requirements and theoretical and experimental comparison. Special beam forming required in the telemetry applications are achieved with better gain especially for the aim of wide beams. The use of the new approach will show the beam forming advantage of radiating the energy to high elevation angles.
Abstract: This review deals with the design of a new reconfigurable beam antenna used to improve the efficiency of spatial telemetry links on Nano-Satellite. Advances in this domain show the needs to serve some applications with special electromagnetic beams and polarization patterns especially from LEO and MEO Space-Earth links. The RF front end must be cap...
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Water Supply System in Pabna Municipality of Bangladesh: A Case Study
Mohammad Atauzzaman,
Mohammad Yousuf Ali,
Musammat Meherun Nesa
Issue:
Volume 5, Issue 1, March 2020
Pages:
20-24
Received:
9 January 2020
Accepted:
29 January 2020
Published:
4 February 2020
Abstract: Safe and adequate water supply is a challenging task in many developing cities like Pabna. People have been facing water supply problems e.g. odor, turbidity, iron, etc., thus leading to public health risk e.g. typhoid, skin disease, allergy, etc. This paper presents the existing water supply system of ward no. 5 of Pabna municipality. Primary data were collected from the householders through questionnaire and field visit to the study area during October, 2018 to April, 2019. The valuable information, ward map, etc. were collected from the respective officials of Pabna municipality. The collected data and information were then analysed. 19% householders use groundwater, 9% householders use public supply water and the rest use both. They use groundwater for drinking purposes and supply water for domestic purposes. 71% householders use water 80~100 lpcd and 29% householders use water 60~80 lpcd for their daily usages e.g. drinking, cooking, bathing, washing, defecation, etc. They use more water at morning and noon. 17% householders face occasionally and 32% householders face rarely the shortage of water. In supply water, odor is high at 46% houses, medium at 30% houses and low at 12% houses and turbidity medium at 10% houses and low at 76% houses. Supply water contains iron; high at 2% houses, medium at 39% houses and low at 46% houses. Arsenic is not present in both groundwater and supply water. Drinking water quality is very good at 12% houses, good at 15% houses and satisfactory at 73% houses. Some householders use filtered or boiled water for drinking. 90% householders use economic water closets. 20% householders are affected by water borne diseases e.g. skin disease, allergy, etc. The study helps understand the nature and type of water supply problems faced by the dwellers of Pabna municipality.
Abstract: Safe and adequate water supply is a challenging task in many developing cities like Pabna. People have been facing water supply problems e.g. odor, turbidity, iron, etc., thus leading to public health risk e.g. typhoid, skin disease, allergy, etc. This paper presents the existing water supply system of ward no. 5 of Pabna municipality. Primary data...
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Assessment on the Quality of Concrete Materials Used in Building Construction Projects: A Case Study in Assosa University
Bekele Arega Demissie,
Ashebir Belete Werkineh
Issue:
Volume 5, Issue 1, March 2020
Pages:
25-32
Received:
16 December 2019
Accepted:
31 December 2019
Published:
11 February 2020
Abstract: Concrete is an intimate mixture of Coarse Aggregate, Sand (Fine Aggregate), Cement and Water. In building construction, most of the activities are executed using concrete so that Concrete materials quality is important. Construction materials used in construction determine the behavior of the structure and resulted in any types of failures or defects. The objective of this study was the assessment on the quality of concrete materials used in building construction projects, specifically to identify types of concrete materials used in Assosa University, to determine properties of concrete materials and to compare with standard. The methodologies includes, data collection methods (field observation and laboratory test), and organized data, data-analyzed and conclusion made from the result of data analysis and forwarded recommendations. Based on the findings, the determined properties of materials includes silt content of sands, 4.64%, 3.85%, 9.26%, 11.67%; Gs (ssd), 2.430%, 2.595%, 2.465%, 2.492%; compacted unit weight, 1407.94 Kg/m3, 1498.00 Kg/m3, 1348.92 Kg/m3, 1303.08 Kg/m3; and Bambasi, Sherkole Kumeruk and Fududu respectively.
Abstract: Concrete is an intimate mixture of Coarse Aggregate, Sand (Fine Aggregate), Cement and Water. In building construction, most of the activities are executed using concrete so that Concrete materials quality is important. Construction materials used in construction determine the behavior of the structure and resulted in any types of failures or defec...
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Investigation All Types of Aircraft Noises: Review Paper
Mojtaba Sadeghian,
Mofid Gorji-Bandpy
Issue:
Volume 5, Issue 1, March 2020
Pages:
33-41
Received:
8 January 2020
Accepted:
2 March 2020
Published:
10 March 2020
Abstract: This article presents a review of current aircraft noises. Noise is a fascinating area of research combining statistics, applied mathematics, and engineering. Aircraft noises are an impact of enormous financial, environmental, and technological issue. Aircraft noise remains the key inhibitor of the growth of air transportation and remains an acute environmental problem that requires advanced solutions. To advance our understanding of the sound source mechanisms, it should be noted that predominant noise sources of aircraft engines are from the exhaust (referred to as the jet) and fan (including the stator). The noise generated in these two areas during takeoff and landing has a strong influence on the communities around the airports. One of the most important sources of aircraft noises in modern jet aircraft is the turbulence that occurs in the shear layers around the engine’s exhaust. But this is not just an academic issue also jet noise is highly relevant to the aviation industry and on a wider scale, has been related to economic, social, and subsequently political. To deal with this problem, aircraft manufacturers and public establishments are engaged in research on technical and theoretical approaches for noise reduction concepts that should be applied to new aircraft. This review paper discusses a selection of enabling technologies and their implications on acoustics and noise and gives a perspective on future trends and new directions in aeroacoustics required to address the challenges.
Abstract: This article presents a review of current aircraft noises. Noise is a fascinating area of research combining statistics, applied mathematics, and engineering. Aircraft noises are an impact of enormous financial, environmental, and technological issue. Aircraft noise remains the key inhibitor of the growth of air transportation and remains an acute ...
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Analysis of Innovations in Concentration of Solar Radiation
Elhadj Ali Aoudou,
Benoit Ndzana
Issue:
Volume 5, Issue 1, March 2020
Pages:
42-47
Received:
9 January 2020
Accepted:
6 March 2020
Published:
31 March 2020
Abstract: As part of my research work carried out successfully at the level of Master 2 in 2016, in the laboratory of Electrical Engineering, Mechatronics and Signal Processing, I designed a TVS central, which allowed me to replace the use of diesel fuel by solar energy in the production of electrical energy. This solar power plant was named: TVS system. Its solar energy collector is parabolic and well suited to urban areas. I have noticed that its installation, operation and maintenance are complex and require good training for officers working at the plant. The rural area is not electrified in Cameroon it has been very interesting to extend the use of the TVS system in rural areas since water and the sun being available in these places, it will work with steam which will allow to have a kW at lower cost. It will be a question for me in the context of performance research in the production of electricity, to redesign the TVS system with innovative solar energy collection equipment which also allows to add a thermal storage system to overcome lack of sunshine at night. The process of producing electricity from solar radiation is complex for concentrated solar energy, but direct for voltaic panels. Since the solar energy is not very dense, it is necessary to concentrate it to obtain exploitable temperatures for the production of high-power electricity. These sought temperatures are between 400°C and 600°C. Figure 1 below shows the capture of solar radiation and the movements of the thermal energy received until its transformation into mechanical movement driving the alternator. The solar energy production sector has become dynamic all over the world and we are witnessing various promising innovations which will announce the primordial place that renewable energies will occupy in the near future. Today, solar energy is estimated at 19% of the world's electric energy. During my thesis work, I propose to: analyze of innovations in concentration of solar radiation. [10]
Abstract: As part of my research work carried out successfully at the level of Master 2 in 2016, in the laboratory of Electrical Engineering, Mechatronics and Signal Processing, I designed a TVS central, which allowed me to replace the use of diesel fuel by solar energy in the production of electrical energy. This solar power plant was named: TVS system. Its...
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Controlling Solar Radiation Is a Performance Indicator for a Solar Power Plant
Elhadj Ali Aoudou,
Benoit Ndzana
Issue:
Volume 5, Issue 1, March 2020
Pages:
48-55
Received:
9 January 2020
Accepted:
6 March 2020
Published:
8 March 2020
Abstract: Certain regions of Africa are classified as a zone rich in hydrocarbons. We are talking about the Maghreb area and the Gulf of Guinea. The countries most concerned are: Libya, Algeria, South Sudan, Nigeria, Congo Brazzaville, Angola, Gabon, Equatorial Guinea and many others are recognized as producers of oil, therefore supposedly rich in foreign currency. These countries find it difficult to cope with the problems of managing their poorly managed oil manna: they can lead their country to neglect the agriculture that has always fed Africa. It can be said that these countries did not develop their industries through this oil revenue. Others strongly assert that oil is a source of misfortune in Africa because the population does not benefit from these oil revenues. Today this population is facing global warming due to the greenhouse effect. World conferences recommend reducing CO2 emission. Some countries are said to be "polluters" and the concept "polluter pays" is accepted. Above all, finding a sickle fuel resource is a world-famous event; all the nations of the earth would like to be the owner of this discovery, but we know that today these resources are limited and even threatened with disappearance: some advance the time remaining between 30 and 100 years. The earth's fuel resources are running out day by day alongside ever-increasing global demand. The sharp rise in the price of oil in 1973 led the world to focus more and more on renewable energy sources, first and foremost solar energy. This one wants to be free and available on a large part of the terrestrial globe. When one tries to calculate the energy balances of a solar installation, it is often of the continual variation of solar radiation that the main problems are born. The mastery of the estimation of the sun leads us towards a study of the environmental climatology: the case of Cameroon, so that Controlling Solar Radiation is a Performance Indicator for a Solar Power Plant.
Abstract: Certain regions of Africa are classified as a zone rich in hydrocarbons. We are talking about the Maghreb area and the Gulf of Guinea. The countries most concerned are: Libya, Algeria, South Sudan, Nigeria, Congo Brazzaville, Angola, Gabon, Equatorial Guinea and many others are recognized as producers of oil, therefore supposedly rich in foreign cu...
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