Competitive Assessments for HAP Delivery of Mobile Services in Emerging Countries

In recent years, network deployment based on High Altitude Platforms (HAPs) has gained momentum through several initiatives where air vehicles and telecommunications payloads have been adapted and refined, resulting in more efficient and less expensive platforms. In this paper, we study HAP as an alternative or complementary fast-evolving technology to provide mobile services in rural areas of emerging countries, where business models need to be carefully tailored to the reality of their related markets. In these large areas with low user density, mobile services uptake is likely to be slowed by a service profitability which is in turn limited by a relatively low average revenue per user. Through three architectures enabling different business roles and using different terrestrial, HAP and satellite backhaul solutions, we devise how to use in an efficient and profitable fashion these multi-purpose aerial platforms, in complement to existing access and backhauling satellite or terrestrial technologies

The suitability of coconut shell concrete as a replacements in term of mechanical and thermal properties – a review

The most critical issue in environment protection and natural resource conservation is waste management [1]. Changes in environment and an increase in population are the main causes of the many processes of deterioration which have altered the ecosystem of our planet, including the generation of municipal solid waste (MFS) [2]. Therefore, there is a need to reuse waste to create a greener and healthier place on earth. The usage of agricultural waste will be emphasized in this research. Being renewable, low-cost, lightweight, having high specific strength and stiffness have made agricultural waste ideal for use as construction materials [3]. Coconut shell, oil palm shell, oil palm clinker, corncob ash, and rice husk ash are all agricultural by-products. Although some of these materials can be used as animal feed or fuel in biomass power plants or boilers of various industrial sectors to produce steam, a lot of these materials are still disposed off into landfills or burnt. This leads to serious environmental problems..

Two lighter than air systems in opposing flight regimes: An unmanned short haul, heavy load transport balloon and a manned, light payload airship

Lighter Than Air vehicles are generally defined or categorized by the shape of the balloon, payload capacity and operational flight regime. Two balloon systems that are classed as being in opposite categories are described. One is a cable guided, helium filled, short haul, heavy load transport Lighter Than Air system with a natural shaped envelope. The other is a manned, aerodynamic shaped airship which utilizes hot air as the buoyancy medium and is in the light payload class. While the airship is in the design/fabrication phase with flight tests scheduled for the latter part of 1974, the transport balloon system has been operational for some eight years

Lemon essential oil; the organic insect repellent

Commercial insecticides are widely used in most sectors of the agricultural production to avoid or reduce losses by insects and hence it can improve the production as well as the quality of the product produced. In some ways, it can also improve the value of food and also its safety. Insecticides can be considered as an economic, labour-saving and efficient tool of insect management in agricultural production [1]

In depth review of the 1979 AIAA Lighter-Than-Air Systems Technology Conference

The lighter than air (LTA) systems technology conference is reviewed. Highlights of the conference were: (1) the interest shown in patrol and surveillance airships, particularly for coastal patrol missions; (2) the session devoted to overviews of foreign activity; and (3) heavy lift and long range transport aircraft design considerations

Mobile Ground Station for the Unmanned Elettra-Twin-Flyer Airship

In recent years the development of unmanned platforms has exasperated the concept of design and planning in aeronautics: for unmanned flight, in fact, the aerial segment is no longer the central issue and concepts like mission planning, mission and on board sensor management are becoming more and more critical. The majority of these functionalities have been separated from the aerial segment and transferred to the Ground Station (GS) which is one of the key elements of the Unmanned Aerial System (UAS) together with the Communication Link and the Launch and Recovery Element. Safety requirements are thus transferred to some of the GS components, especially to those which perform critical functions. This has contributed to increase the CS complexity. Regardless of the UAV architecture and overall dimension, in fact, the pilot must be able to operate under the same condition of situation awareness of a correspondent manned aircraft. In this context, advanced vision systems and innovative human-machine interfaces must be designed, to enable the pilot to process the flight data while accomplishing the mission task. This paper presents a technological solutions adopted for the Elettra-Twin-Flyer, a lighter-than-air unmanned platform, developed for civil applications

New Approach and Results on the Stability and Control of Airship

Il rinnovato interesse per l’utilizzo dei dirigibili ha evidenziato la necessità di sviluppare nuovi metodi e tecniche per valutarne le caratteristiche di stabilità ed il comportamento dinamico. Inizialmente è stato ricercato un metodo per analizzare la stabilità del dirigibile a partire dalle equazioni linearizzate del moto. E’ stato sviluppato il modello dinamico teorico per un piccolo dirigibile, l’AIUX15, e successivamente implementato in ambiente Matlab/Simulink per due diverse configurazioni di impennaggi d’interesse. Analisi ingegneristiche ed test preliminari condotti sul prototipo del dirigibile AIUX15 hanno evidenziato la significativa influenza degli impennaggi in termini di peso e assetto. Uno degli obiettivi perseguiti è stato lo sviluppo di diversi approcci di controllo in aria calma ed in turbolenza, con la finalità di controllare i moti oscillatori di rollio; tali oscillazioni rappresentano una fonte di disturbo per i sistemi di acquisizione dati che costituiscono il principale carico pagante di questa tipologia di dirigibili. Infine è stato condotto uno studio preliminare per il calcolo delle derivative di stabilità del dirigibile mediante prove sperimentali nella vasca navale, basato sul metodo delle oscillazioni forzate

MODELING OF INNOVATIVE LIGHTER-THAN-AIR UAV FOR LOGISTICS, SURVEILLANCE AND RESCUE OPERATIONS

An unmanned aerial vehicle (UAV) is an aircraft that can operate without the presence of pilots, either through remote control or automated systems. The first part of the dissertation provides an overview of the various types of UAVs and their design features. The second section delves into specific experiences using UAVs as part of an automated monitoring system to identify potential problems such as pipeline leaks or equipment damage by conducting airborne surveys.Lighter-than-air UAVs, such as airships, can be used for various applications, from aerial photography, including surveying terrain, monitoring an area for security purposes and gathering information about weather patterns to surveillance. The third part reveals the applications of UAVs for assisting in search and rescue operations in disaster situations and transporting natural gas. Using PowerSim software, a model of airship behaviour was created to analyze the sprint-and-drift concept and study methods of increasing the operational time of airships while having a lower environmental impact when compared to a constantly switched-on engine. The analysis provided a reliable percentage of finding the victim during patrolling operations, although it did not account for victim behaviour. The study has also shown that airships may serve as a viable alternative to pipeline transportation for natural gas. The technology has the potential to revolutionize natural gas transportation, optimizing efficiency and reducing environmental impact. Additionally, airships have a unique advantage in accessing remote and otherwise inaccessible areas, providing significant benefits in the energy sector. The employment of this technology was studied to be effective in specific scenarios, and it will be worth continuing to study it for a positive impact on society and the environment

Aeronautical Engineering: A special bibliography with indexes, supplement 69

This bibliography lists 305 reports, articles, and other documents introduced into the NASA scientific and technical information system in March 1976