Implementation of African Satellite Augmentation System (ASAS) for Maritime Applications

This paper introduces implementation of the new project known as African Satellite Augmentation System (ASAS) for Africa and Middle East, designed by the CNS Systems Company and its research group supported by partners. The ASAS project as Regional Satellite Augmentation Systems (RSAS) will provide service for maritime, land (road and rail), and aeronautical applications. Thus, with existing and other newly designed RSAS networks, it will be integrated in Global Satellite Augmentation System (GSAS) with new Satellite Communication, Navigation and Surveillance (CNS) for improved Ship Traffic Control (STC) and Ship Traffic Management (STM). This System also enhances safety and emergency systems, transport security and control of ocean shipping freight, logistics and the security of the crew and passengers onboard ships and fishing vessels as well. The current CNS infrastructures of the first generation of Global Navigation Satellite System (GNSS-1) applications are represented by old fundamental solutions for Position, Velocity, and Time (PVT) of the satellite navigation and determination systems, such as the US GPS and Russian (former USSR) GLONASS military requirements, respectively. The establishment of Space, Ground, and User segment, including Local Satellite Augmentation System (LSAS), are discussed as a new basic infrastructures for maritime and other mobile applications, which will be integrated with RSAS in the future GSAS network

Architecture of the global navigation satellite system for maritime applications

This paper introduces architecture of the global navigation satellite system (GNSS) networks in the function of the maritime space communications, navigation and surveillance (CNS) for enhanced navigation and positioning of vessels deploying passive, active and hybrid global determination satellite systems (GDSS) networks. These GNSS networks have to enhance safety and control oceangoing ships in navigation across the ocean and inland waters, to improve logistics and freight of goods, security of crew and passengers onboard ships. The maritime GNSS networks integrated with geostationary earth orbit (GEO) satellite constellations are providing important global satellite augmentation systems (GSAS) architecture, which is established by two first generations known GNSS as GNSS-1 infrastructures. The GNSS-1 network is the composition of two subnets such as the US global position system (GPS) and Russian global satellite navigation system (GLONASS). Both GNSS-1 networks play a significant contribution in very precise timing, tracking, guidance, determination and navigation of the oceangoing ships. At this point, both GNSS-1 networks, GPS and GLONASS, are used in maritime and many other mobile and fixed applications to provide enhanced accuracy and high integrity monitoring usable for positioning of the oceangoing ships. To provide improvements of GNSS-1 network it will be necessary to carry out their augmentation within several regional satellite augmentation systems (RSAS) as integration parts of GSAS infrastructures

Architecture of the regional satellite augmentation system for maritime applications

This paper describes architecture of regional satellite augmentation system (RSAS) in the function of the maritime space communications, navigation and surveillance (CNS) and global navigation satellite systems (GNSS) networks for enhanced safety and surveying of oceangoing ships, management and tracking of cargo, security of Mariners onboard commercial and passenger ships, yachts, sea platforms and other types of craft. The RSAS network are designed to improve vessel management and transport operation because of the enormous expansion of the world's merchant fleet. However, this network with a special ship tracking system can also improve the protection of merchant ships and their crews against piracy, violence, robbery and terrorist attacks. The international maritime organization (IMO) and shipping flag states have project for development of the international ship and port security (ISPS) and design to implement an approaching and port control system (APCS) by special code for all merchant vessels including determination, tracking and positioning of all ships movements in and out of the seaport area. The Maritime RSAS and CNS systems are integration components of the global satellite augmentation systems (GSAS) of two operational GNSS-1 military networks, such as the US global position system (GPS) and Russian global satellite navigation system (GLONASS). In this paper are also introduced the special effects of the ships RSAS networks and coastal movement guidance and control (CMGC) system for maritime application at sea and in seaports areas

Establishment of GPS Reference Network in Ghana

The quest for the use of GNSS in developing countries is on the rise following the realization of its numerous advantages over the conventional methods of positioning, navigation and timing. Africa's attempt to harness this technology has made it imperative to investigate the regional problems associated with its implementation by its member states, which constitute the AFREF. This study goes beyond the establishment of a GNSS reference network in Ghana by investigating and finding solutions to some of the regional problems associated with its implementation. The problem of turbulent atmospheric conditions which includes the severe ionospheric fluctuations and the erratic tropospheric conditions coupled with the sparsely populated base stations has led to the development of a new concept of correction, the Corridor Correction, which is able to correct the atmospheric effect comparable with the established concepts like the Virtual Reference Station, VRS, Flaechen-Korrektur-Parameter, FKP and Master Auxiliary Concept, MAC. In spite of the ionospheric problems in the equatorial region, the number of single frequency receivers in use for precise positioning is on the increase as compared with the relatively few multiple frequency receivers. This has necessitated the investigation of the code-plus-carrier processing approach which uses the idea of opposite signs of the propagation delay of the ionosphere in the code and carrier signals to eliminate the ionospheric delay, which normally requires dual frequency receivers to do same. This improved processing technique has led to the achievement of an accuracy of 5 cm with single frequency over a distance of 194 km. Sub-decimeter is generally achieved after 12 hours and 18 hours of observation for a distance of 200 km and 1200 km respectively with this technique as shown in this study. In addition to the improved processing techniques, the ambiguity that characterizes the use of mean-sea-level for the definition of vertical references as a result of either the sea level change or movement of the earth crust can be resolved with the use of GNSS which is independent of these two phenomena. This is achieved by collocating a GPS base station at the reference tide gauge located at Takoradi. The orthometric height derived from the tide gauge and the corresponding ellipsoidal height at the collocated GNSS base station is used to determine the local quasi-geoid. This is compared with the global geoid derived from EGM96, the global model from NGA, to obtain a difference that can be applied as a correction factor to obtain orthometric heights. The release of EGM2008 which has undergone remarkable improvement over EGM96 in terms of resolution makes it important to investigate into how it can be used to improve the orthometric height determination using ellipsoidal heights from GNSS observation. This can be achieved by following up what has been derived with EGM96 at the Takoradi tide gauge with this newly released EGM2008. To be able to move through a smooth transition from the existing geodetic reference system based on the War Office Ellipsoid to the newly established system based on the geocentric ITRF05, a set of seven parameter transformation has been derived for the project area, the Golden Triangle of Ghana.Das Bestreben GNSS in Entwicklungsländern zu nutzen nimmt stetig zu, da man die zahlreichen Vorteile gegenüber herkömmlichen Verfahren der Positionierung, Navigation und Zeitübertragung erkannt hat. Afrikas Versuch, diese Technologie zu nutzen, gebietet es, die regionalen Probleme im Zusammenhang mit der Umsetzung durch die AFREF Mitgliedsstaaten zu untersuchen. Diese Abhandlung geht über die Errichtung eines GNSS Referenznetzwerks in Ghana hinaus, indem sie Lösungen zu einigen regionalen Problemen in der Umsetzung aufzeigt und untersucht. Das Problem der turbulenten Atmosphäre, die schweren ionospärische Fluktuationen und sprunghafte troposphärische Bedingungen verbunden mit den sehr spärlich gestreuten Referenzstationen, hat zu der Entwicklung eines neuen Konzeptes von Korrekturverfahren, der Corridor Correction, geführt, die es ermöglicht, atmosphärische Einflüsse ähnlich wie etablierte Verfahren wie Virtual Reference Station, VRS, Flaechen-Korrektur-Paramter, FKP and Master Auxiliary Concept, MAC, zu korrigieren. Trotz der Probleme mit der Ionosphäre in der Äquatorregion, übersteigt die Anzahl der Ein-Frequenz-Empfänger für die präzise Positionierung die der relativ wenigen Mehrfrequenzempfänger. Dies machte die Untersuchung des Code-plus-Carrier Prozessierungsansatzes notwendig. Dieser nutzt den Effekt von unterschiedlichen Vorzeichen bei der Änderung der Ausbreitungsgeschwindigkeit von Code- und Trägersignalen durch die Ionosphäre um den ionosphärischen Effekt zu eliminieren, was in der herkömmlichen Prozessierung Zweifrequenzempfänger benötigt. Diese verbesserte Prozessierungstechnik hat zur Erzielung von Genauigkeiten von 5 cm mit Einfrequenzempfängern über eine Basislinienlänge von 194 km geführt. Damit werden im Allgemeinen Sub-Dezimeter Genauigkeiten nach 12 Stunden Beobachtungsdauer für Basislinienlängen von 200 km bzw. 18 Stunden für Basislinien von 1200 km erreicht, wie diese Abhandlung zeigt. Zusätzlich zu den oben genannten Verbesserungen in der Prozessierung, wird eine Methode aufgezeigt, die die Unsicherheit durch Meeresspiegeländerungen oder Bewegungen der Erdkruste, die der Gebrauch des mittleren Meeresspiegels als Definition des vertikalen Datums in sich birgt, durch den Gebrauch von GNSS, das von diesen beiden Phänomenen unberührt ist. Dies wird dadurch erreicht, dass GPS Basisstationen an Orten mit einer Pegelstation eingerichtet werden. Die orthometrische Höhe des Referenzpegels und die ellipsoidische Höhe der Basisstation werden dann zur Bestimmung eines lokalen Geoids verwendet. Das in dieser Abhandlung verwendete lokale Geoid ist an das globale Geoid angeschlossen worden, das aus dem EGM96, dem Modell der NGA, abgeleitet ist. Die Veröffentlichung des EGM2008, das gegenüber dem EGM96 im Hinblick auf die Auflösung erfahren hat bedeutende Verbesserungen, erfordert es, zu untersuchen, wie es Ghana zur Bestimmung von orthometrischen Höhen durch GNSS Beobachtungen nutzen kann. Das kann durch eine Weiterentwicklung des Ansatzes erreicht werden, der in dieser Studie schon mit dem EGM96 für Ghana bei Takoradi begonnen wurde. Das hierbei aufgebaute GNSS Referenznetzwerk wurde an den Pegel von Takoradi angeschlossen, einem der ältesten Level auf dem afrikanischen Kontinent. Um einen glatten Übergang vom vorhandenen Referenzsystem, das auf dem War Office Ellipsoid basiert, zum neuen, auf dem ITRF05 basierendem System zu ermöglichen, wurde ein Satz von sieben Transformationsparametern abgeleitet, die auf den Messungen im Projektgebiet „Goldenes Dreieck“ in Ghana basieren

Air Traffic Management Abbreviation Compendium

As in all fields of work, an unmanageable number of abbreviations are used today in aviation for terms, definitions, commands, standards and technical descriptions. This applies in general to the areas of aeronautical communication, navigation and surveillance, cockpit and air traffic control working positions, passenger and cargo transport, and all other areas of flight planning, organization and guidance. In addition, many abbreviations are used more than once or have different meanings in different languages. In order to obtain an overview of the most common abbreviations used in air traffic management, organizations like EUROCONTROL, FAA, DWD and DLR have published lists of abbreviations in the past, which have also been enclosed in this document. In addition, abbreviations from some larger international projects related to aviation have been included to provide users with a directory as complete as possible. This means that the second edition of the Air Traffic Management Abbreviation Compendium includes now around 16,500 abbreviations and acronyms from the field of aviation

Department of Defense Dictionary of Military and Associated Terms

The Joint Publication 1-02, Department of Defense Dictionary of Military and Associated Terms sets forth standard US military and associated terminology to encompass the joint activity of the Armed Forces of the United States. These military and associated terms, together with their definitions, constitute approved Department of Defense (DOD) terminology for general use by all DOD components

NASA earth science and applications division: The program and plans for FY 1988-1989-1990

Described here are the Division's research goals, priorities and emphases for the next several years and an outline of longer term plans. Included are highlights of recent accomplishments, current activities in FY 1988, research emphases in FY 1989, and longer term future plans. Data and information systems, the Geodynamics Program, the Land Processes Program, the Oceanic Processes Program, the Atmospheric Dynamics and Radiation Program, the Atmospheric Chemistry Program, and space flight programs are among the topic covered

Space and Earth Sciences, Computer Systems, and Scientific Data Analysis Support, Volume 1

This Final Progress Report covers the specific technical activities of Hughes STX Corporation for the last contract triannual period of 1 June through 30 Sep. 1993, in support of assigned task activities at Goddard Space Flight Center (GSFC). It also provides a brief summary of work throughout the contract period of performance on each active task. Technical activity is presented in Volume 1, while financial and level-of-effort data is presented in Volume 2. Technical support was provided to all Division and Laboratories of Goddard's Space Sciences and Earth Sciences Directorates. Types of support include: scientific programming, systems programming, computer management, mission planning, scientific investigation, data analysis, data processing, data base creation and maintenance, instrumentation development, and management services. Mission and instruments supported include: ROSAT, Astro-D, BBXRT, XTE, AXAF, GRO, COBE, WIND, UIT, SMM, STIS, HEIDI, DE, URAP, CRRES, Voyagers, ISEE, San Marco, LAGEOS, TOPEX/Poseidon, Pioneer-Venus, Galileo, Cassini, Nimbus-7/TOMS, Meteor-3/TOMS, FIFE, BOREAS, TRMM, AVHRR, and Landsat. Accomplishments include: development of computing programs for mission science and data analysis, supercomputer applications support, computer network support, computational upgrades for data archival and analysis centers, end-to-end management for mission data flow, scientific modeling and results in the fields of space and Earth physics, planning and design of GSFC VO DAAC and VO IMS, fabrication, assembly, and testing of mission instrumentation, and design of mission operations center

Precious Forests

Forests are the dominant terrestrial ecosystem of Earth. They are distributed across the globe. Forests account for 75% of the gross primary productivity of the Earth's biosphere, and contain 80% of the Earth's plant biomass. Human society and forests influence each other in both positive and negative ways. Forests provide ecosystem services to humans. Forests can also impose costs, affect people's health, and interfere with tourist enjoyment. This publication presents reviews and research results on negative and positive human interference on forests, as well as ecology, management, governance, policy and economic issues. The book consists of four sections with 12 chapters derived from around the world

Assessing sanitary mixtures in East African cities

The urbanisation of poverty and informality in East African cities poses a threat to environmental health, perpetuates social exclusion and inequalities, and creates service gaps (UN-Habitat, 2008). This makes conventional sanitation provision untenable citywide, giving rise to the emergence of sanitation mixtures. Sanitation mixtures have different scales, institutional arrangements, user groups, and rationalities for their establishment, location, and management. For assessing the performance of both the mixtures as a whole and the different sanitation approaches constituting these mixtures, novel approaches for analyses are required. This thesis, therefore, departs from the centralised-decentralised approaches to a modernised mixtures (MM) approach in seeking a more inclusive assessment of sanitary configurations taking into account public and environmental health, accessibility and flexibility of sanitation systems as sustainability criteria. To achieve this, the four objectives formulated for this thesis are to: 1. Make an inventory of sanitary systems in Kampala and Kisumu. 2. Assess and map sanitary systems along MM dimensions in Kampala and Kisumu. 3. Assess sustainability of sanitary systems on defined MM criteria in Kampala and Kisumu. 4. Enhance insights on the applicability of MM criteria as conceptual model, assessment and prescriptive tool for sanitary mixtures in East African cities. Case study cities were chosen from a typology of primary and secondary cities that have urban sewer systems since colonial times. The two cities were deemed to offer rich cases that would give a general outlook of other East Africa cities, thus can offer possibilities for generalization. The thesis utilised a multi-method and multi-level approach in data collection and analysis. A multicriteria analysis is used in sustainability performance assessment of sanitation systems based on defined MM criteria. Firstly, modernisation debates and resultant modernities in sanitation provision were reviewed in Chapter 2. The review shows that Western modernisation and resultant modernities and their structures of service provision have not resonated well in developing countries. Consequently, alternative theories that dispute a universal approach to modernity emerged to offer alternatives to modernisation. Alternative options are characterised by multiple rationalities, diversity and multiplicity. Modernities in terms of sanitation provision are further operationalized as competition between the proponents of centralised versus decentralised solutions. A third way of looking at sanitation modernisation that is more inclusive is advanced through the introduction of the MM approach. In Chapter 3, the presence of urban sewer systems in Kampala and Kisumu cities is assessed. The results show that urban systems are of medium scale and serve about 10% of the city population. They are publicly owned and managed by public enterprises under new public management. Besides, they are conventionally designed, constructed and operated without the involvement of end-users. Treatment plants are either overloaded, underutilised or treatment stages are mismatched. Consequently, about 30-70% of the treatment stages are not operational. Effluent discharge standards and bio-solids reuse requirements are not met, and the adopted treatment technologies are inappropriate for the investigated conditions. Sewer networks are supported by pumping stations and siphons that are only partially operational due to high operational costs and mechanical failures. Public sewerage is further plagued by urban informality and multiplicity of city spatial structures. Planned city core, and to a limited extent peri-urban areas, are served by public sewers, while sewer trunk lines pass through informal slum settlements without connections. In Chapter 4, satellite systems are analysed and configurations mapped. Satellite systems are intermediate semi-collective decentralised sewerage and treatment systems developed parallel to urban and onsite systems. They are provided by multiple actors, serve planned middle and high income residential, industrial complexes, endowed public and private universities, and government facilities. In terms of scale, they are community, neighbourhood and small-urban sanitation solutions. Besides, satellite systems are private sewerage systems that utilise gravity sewers and localised mechanised or non-mechanised treatment. The flows are based on land use or facility specific and are treated close to the point of generation. They are based on conventional designs and construction protocols without end-user involvement. Onsite systems in Kampala and Kisumu cities are examined in Chapter 5. Planning forecast indicates that onsite systems will dominate sewer (urban and satellite) systems beyond the next two decades. They are small-scale, highly decentralised and use simple technologies. Pit latrines dominate septic tanks in number, with eco-san on pilot scales and bio-latrine being a new sanitation option. Faecal sludge collection, treatment and safe disposal is dismal. The private sector dominates over local authorities in provision of faecal sludge services, but public sewerage agencies receive and co-treat faecal sludge with sewage although sewage works are not designed to receive faecal sludge. They are regulated by the Ministry of Health, enforced by the city councils and are provided by multiple actors solely or in partnership. Onsite sanitation can be a transient or permanent solution depending on mass flows and spatial requirements. However, for better sanitation provision, a permanent solution, with room for amendments to anticipate changes in space and mass flow is imperative. In Chapter 6, sustainability performance of sanitation systems are assessed following the defined three MM criteria. The performance shows that there is no sanitation system that is completely outcompeted in performance, neither are there systems with a very good performance. Sanitation system choices, consequently, are made among imperfect options, which call for balancing the various elements of sanitation provision to suit different policy and local contexts. Varying the assigned relative weight of the various criteria used in the overall MCA assessment indicates that generally, any slight increase in weight has an impact on systems that already have a high performance whereas in the case of systems with low performance the change is dismal or even negative. Therefore, programmes for improvement of sanitation systems might be directed to improvement options where systems already have a relatively high performance. However, those with a low performance may need comprehensive or even system reconfigurations for significant impacts to be realised. In conclusion, sanitation mixtures are theorised as the co-existence of different phases of modernity in tandem with local context variables. Thus, there is no one-fit-all paradigmatic way to sanitation provision if the local contexts are apparently different even within the same city. However, a shift of the centralised-decentralised dichotomy to modernised mixtures paradigm offers better impetus as it can utilise the advantages of both centralised and decentralised approaches without jeopardising existing provision pathways. The MM approach is helpful in assessing, mapping and describing sanitation systems in cities where sanitation mixtures are the norm rather than the exception. One way to modernise sanitation mixtures is by shifting the centralised-decentralised paradigm in order to modernise the mixed sanitation landscape. This is premised on the notion that such a shift will result in merging the strengths of centralised approach, e.g. economies of scale, efficiency, and convenience, with strengths of decentralised approach, e.g. accessibility, flexibility, participation, and reuse and recovery in development of intermediate systems configuration. This can be achieved through, among others, avoiding use of pumping stations, adoption of multiple service levels, involvement of private sector, servicing households at intermediate scale, and establishing sanitation suitability and management zones. The MM approach is also very helpful as a conceptual model for organising a research agenda which can be set along the four assessment dimensions of scale, management, flows and participation, as well as in searching for appropriate intervention measures along one or more of these dimensions. As an assessment and decision making tool, it is helpful in finding out which elements highlighted in the sustainability assessment need to be restructured and which need improvement in order to enhance their sustainability. However, translation of the proposed conceptual MM model into a mathematical model is a challenge yet to be explored. Considering its intrinsic dynamic character in dependence to varying spaces, flows, and scales along city development, a mathematical MM model would provide a regulatory design tool for city planners for adopting amendments to existing sanitation solutions. Obviously, up to date monitoring and inventory records are a pre-requisite for applying such a model, requiring institutional upgrading. Although the current results described in this thesis provide the basis for a more structured assessment and generalisation of sanitation mixtures, more research and contextualisation is needed in other regions, for further elaboration of MM model, and for the refinement of the assessment tool. </p