The quality of service of mobilesatellite reception can be improved by using multi-satellite diversity (angle diversity). The recently ﬁnalised MiLADY project targeted therefore on the evaluation and modelling of the multi-satellite propagation channel for landmobile users with focus on broadcasting applications. The narrowband model combines the parameters from two measurement campaigns: In the U.S. the power levels of the Satellite Digital Audio Radio Services were recorded with a high sample rate to analyse fast and slow fading eﬀects in great detail. In a complementary campaign signals of Global Navigation Satellite Systems (GNSS) were analysed to obtain information about the slow fading correlation for almost any satellite constellation. The new channel model can be used to generate time series for various satellite constellations in diﬀerent environments. This article focuses on realistic state sequence modelling for angle diversity, conﬁning on two satellites. For this purpose, diﬀerent state modelling methods providing a joint generation of the states ‘good good’, ‘good bad’, ‘bad good’ and ‘bad bad’ are compared. Measurements and re-simulated data are analysed for various elevation combinations and azimuth separations in terms of the state probabilities, state duration statistics, and correlation coeﬃcients. The ﬁnally proposed state model is based on semi-Markov chains assuming a log-normal state duration distribution.
Globalstar uses Low Earth Orbit (LEO) Satellites in an orbit around 900 miles. There are advantages of LEO satellites over Geosynchronous (GEO) systems for delivery of MobileSatellite Services (MSSs). LEO satellite technology allows the use of low power handheld devices allowing users to be continuously on the move without a disruption of service. In land-based GEO satellite applications (i.e. VSAT or BGAN) the terminal must be stationary to acquire a satellite signal. GEO satellite systems are normally 28,000 miles above the earth and are commonly used for television transmission, high- speed data, and other wideband services. Emergency personnel and first responders require telephone quality transmissions. The time delay and echo inherent with GEO systems can be detrimental to providing life-saving services.
Mobilesatellite communication systems are designed to provide truly global coverage using constellation of low, medium, or geostationary earth orbit satellites. These systems may suffer from poorer quality of service due to high free-space path loss, tree or hills shadowing and multipath due to structures in the vicinity of the mobile. The first two effects mainly influence the line-of-sight LOS (or the direct) path and result in large scale fading, which causes severe signal attenuation especially at small satellite elevation angles. The last one is responsible for small scale fading and time spreading in the received signal, which occurs due to the vector addition of re- flections, diffractions and scattering from local objects such as buildings . Statistical approaches have been used for modeling the LMS channel . These model are simpler, however, due to lack of physical background, such models may provide unreliable results. On the other hand, deterministic models provide high accuracy, but they require actual analytical path profiles and time- consuming computations . A combination of both ap- proaches has been also developed . In general these models can be classified in to narrowband and wideband models. The first one is concerned with voice/data appli- cations of smaller signal bandwidth with respect to the
These are the lands characterised by exposures of massive rocks, sheet rocks, stony pavements or land with excessive surface accumulation of stones that render them unsuitable for production of any green biomass. Such lands are easily discriminated from other categories of waste lands because of their characteristic spectral response. This appears in greenish blue to yellow to brownish tone (subject to varying rock type), vary in size with irregular and discontinuous shapes, very coarse to coarse medium texture, linear to contiguous and dispersed in pattern. It occurs as steep hill slopes, crest, isolated hillocks, plateau and eroded plains in association with barren and exposed rocks. Barren rock outcrops cover an area of about 16.47 km 2 in the study area.
Photographic elements and field knowledge was utilized to delineate various land use/land cover categories such as agriculture land use, built up area, water surface, bare land and vegetation cover. Satellite data was interpreted using photographic and geo- technical elements besides field knowledge about the study area. For GIS and remote sensing data analysis, a time-series of Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper Plus (ETM+) images were used to derive land use/cover maps of the study area were used (Table 1). Satellite images were geometrically corrected with the Global Positioning System (GPS) points. The images included the visible (bands 1, 2 and 3), the near infrared (NIR), the shortwave infrared (SWIR), and the middle infra- red (MIR) bands with 30 m spatial resolution for TM and ETM+ images. The dataset was mainly downloaded from the archive of Landsat (http://earthexplorer.usgs.gov). After preprocessing the imageries, we performed supervised classification of both im- ageries with maximum likelihood classification algorithm in ERDAS IMAGINE 9.1 us- ing the field data to produce five cover classes.
Abstract—Fading in wireless media is a major difficulty in reliable communications, hence secured data transmission over an unreliable channel needs an additional step of error- correction coding. In this paper we have proposed the Crypto-Coding technique that combines encryption and error-correction as a single primitive. Here turbo code is embedded in public key cryptographic algorithm such as Rivest-Shamir-Adelman (RSA) to achieve security and reliability into a single step. The combined system’s performance is evaluated on LandMobileSatellite (LMS) Channel. The results are compared with the system using ideal encryption and decryption.
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STAR 40-04 Nat Env Satellite, Data & Info Service Center For Satellite Apps And Research Christa Washington email@example.com GOES-R 40-11 Nat Env Satellite, Data & Info Service Geo Opertl Env Satellite Program Ofc Angela Michael firstname.lastname@example.org GOES-R 40-11 Nat Env Satellite, Data & Info Service Geo Opertl Env Satellite Program Ofc Jennifer Clark email@example.com GOES-R 40-11 Nat Env Satellite, Data & Info Service Geo Opertl Env Satellite Program Ofc Nicole Solomon firstname.lastname@example.org
Coastal zones are constantly exposed to changes caused by natural processes, anthropogenic activities or both, which can precariously alter the coastal landscapes of many countries. Thus, monitoring of coastal zones is needed to provide important information about current conditions of a country’s coastal areas by examining changes that are taking place. In this respect, such monitoring can be carried out by traditional ground survey, airborne aerial photo, or remote sensing. However, the former is more effective and efficient as it can extract vital boundary information from satellite images using appropriate image analysis. Nonetheless, shoreline extraction has a number of challenges, and many methods have been proposed to improve such extraction, such as the use of machine learning methods. Thus, this study was carried out to determine the most effective ensemble voting classifier based on two different types of classifiers, comprising 11 single classifiers and 4 ensemble classifiers. Performance criteria of the classifiers were based on the overall accuracy, training time, and testing time. The analysis of the experimental data revealed several interesting results. First, for the combination of single and ensemble classifiers, ensemble classifiers with majority voting of Random Forest and Support Vector Machine RBF kernel were the most effective classifiers, attaining high overall accuracy. Second, for the combination of two single classifiers, Multilayer Perceptron and k-Nearest Neighbor attained high overall accuracy, rendering them as the most effective classifiers in this category of classifiers. Third, there were trade-offs between performance measures, as increased overall accuracy was accompanied by longer training and testing time.
“Please note my substantial comment on the BIRRR Facebook site explaining my grievances. It gives a series of failures in this system which is neither rocket science (excuse the pun) or difficult... But I have experienced nothing but problems trying to get to the point I can even speak to a technician...(which I have never done) ... Problems with incorrect address, poor customer service or even no customer service, […] waiting for a response after 4 separate emails stating our service would be connected since June ... I noted a comment from the CEO of Activ8 stating the phone waiting times have been recently longer than acceptable ... There has been very unacceptable wait times since June when I had my first notification we were to be added to the NBN ... I waited 3 hours one day and was never answered. When I did get through the next day they said they were having some problems with the phone service ... Really... I have made numerous calls over the last few months and none have been answered in under half an hour and most have gone well over, some over an hour ... And then the responses have been mostly the same infuriatingly patronising response ... 'Oh we're sorry you've had that
potentiality of Banka Basin – Kanchannagar area of Bardhaman district. Sikder made an in depth study of agricultural land use with the help of land sat imagery and aerial photography. Change detection is the process of identifying differences in the state of an object or phenomenon by observing it at different points in time (Singh 1989). Satellite remote sensing in conjunction with geographic information system, has been widely applied recognized as an effective and powerful tool in detecting land use land cover change (Ehlers et al., 1990, Weng, 2001). Prakasam (2010) studied the land use and land cover change in Kodaikanal region of Western Ghats in Tamilnadu State of India to observe changes during a span of 40 years from 1969 to 2008, using Landsat satellite data and performing supervised classification techniques, he found that 70% of the region was covered in forests in 1969 but has decreased to 33% in 2008, The built-up lands have increased from 3% to 21% showing that the region is affected by rapid urbanisation which is leading to adverse environmental effects for the identified bio- diversity rich region of Kodaikanal. Change detection studies based on RS and GIS technique have focused on getting information of how much, where and what type of land use land cover change occur between time interval. The present study conducted and assessment on land use land cover change of Purbasthali block I and II through satellite images taken on different times with an aim identifying changes due to human activities and impact on the land resource. In the present study we have studied the general spatial pattern of land use land cover and made an up to date land use land cover study in Purbasthali I and II block of Burdwan district through integrating Remote Sensing and GIS technology. The study has also summarized past 85 years change of land use land cover and searched the cause behind it.
They are launched 36000 km above earth. This type of satellites seems to be stationary with respect to earth. With this type of system the satellite can, at all times, receive and transmit messages to any transmitter or transceiver that is within the fixed geographical area visible to the satellite. A communication system based on geostationary satellites may have more than one satellite to cover a greater percentage of the Earth’s surface (2-3 satellites)
The problem contains two different sets of decision variables. Decision variables denoted as n m c are integers denoting the number of RBs allocated to cellular user c of SP m; and decision variables b m (c,mtc) are binary integers denoting whether M2M user mtc shares the RB(s) assigned to user c of SP m or not. The formulation contains seven constraints. The first two constraints ensure that the threshold SINR for both cellular and M2M users is adhered to. The third constraint mandates that a M2M user shares at most one cellular user’s RB(s). Additionally, the fourth constraint guarantees that at most one M2M pair shares any cellular user’s RB(s). This is to ensure that M2M pairs do not cause interference to each other. The fifth constraint guarantees that each SP is allocated a minimum number of RBs as per the service level agreement (SLA) with the InPr. Lastly, the final two constraints ensure that a minimum guaranteed rate is achieved for both the cellular and M2M pairs respectively. It is worth noting that the feasibility of solving such a problem is ensured by assuming an admission control process (outside the scope of this work) from the literature is applied beforehand . This is because if no admission control process is applied, the problem might not have a solution due to potentially bad channel conditions not allowing some users to meet their minimum rate requirement. It is also worth mentioning that the described model considers only one type of data traffic for each type of users. Other constraints need to be added to the model to represent different data traffic types.
Introduction to Mobile Communication: history and evolution of mobile radio systems, types of mobile wireless services/systems - cellular, WLL, paging, satellite systems, standards, and future trends in personal wireless systems. Cellular concepts and system design fundamentals/frequency management and channel Assignment: Cellular concept and frequency reuse, Multiple Access Schemes, fixed Channel assignment, non-fixed channel assignment and handoff. Interference and system capacity, Trunking and Erlang capacity calculations. Mobile radio propagation Radio wave propagation issues in personal wireless systems, Propagation models, Multipath fading and base band impulse response models, Parameters of mobile multipath channels, Antenna systems in mobile radio.
Analysis of land use/land cover change at a local scale is vital to comprehend about the complex relationships between environmental, economic and social drivers that induce changes and the likely impacts at local level. Moreover, a systematic analysis of land use/cover change is so decisive to exactly understand the extent of change and take essential measures to curb down the rate of changes and protect the land cover resources sustainably . In the study area, there are observable land cover change problems which include widespread de- forestation for several different purposes such as, encroachment of agriculture and settlements into forest areas, charcoal and construction materials produc- tion and severe soil erosion along hilly slopes. However, there are scarce local scale land use/cover change studies in southeastern Ethiopia in general and Agarfa district in particular. As the study area borders BMNP which is one of the world’s hotspot areas that harbors variety of endemic animal and plant species, evaluation of the impacts of land use/cover change on these local ecosystem and livelihoods in this area is relevant and timely. Moreover, information on land use/cover change and its possibilities for ideal use is essential for the selection, planning and implementation of land use schemes to meet the increasing de- mands of basic human needs and wellbeing. Thus, the study evaluated the spa- tio-temporal pattern changes of land use/land cover with associated causes of al- teration in the study area. This information also assists in monitoring the changes in land use resulting from changing demands of increasing human pop- ulation .
Clearness in procedures for acquiring services to the public is critical in improving good governance and particularly transparency .As it can be shown in the table 13 an estimate of 66 (43.1%) respondents replied that the office never makes the procedures clear for acquiring services and on the other hand around 63(41.2%) replied that the offices procedures for acquiring services are clear to all stakeholders on rare occasions and about 8(5.2%) responded that they ca not decide whether procedures for acquiring services are clear to all stakeholders and around 10(6.5%) replied procedures for acquiring services are clear to all stakeholders some times while around6(3.9%) responded that the procedures for acquiring services are always clear .From this survey the researcher understands that the office is lagging behind in making the procedures and process for acquiring services clear to the community. In this regard this situation plays it role in diminishing the strive for improving good governance and in particular reference to transparency in the given public institution. The clarity of procedures in land administration will help clients to easily identify the steps to pass the hierarchies to posses land and this in its part play a great role in minimizing the intense bureaucracies.
The FCN model shows promising results in terms of being able to detect smoke pixels in satellite imagery. The immediate extension of this is to prepare the algorithm for operation in conjunction with near-real-time satellite data. Ideally, the algorithm would be able to flag smoke in near real time, prompting an alert to the control center. In Australia, one scenario may be that as a Himawari-8 scan becomes available, the FCN model would do a rapid assessment of the presence of smoke plumes for the entire region of interest (i.e., Australia; CONUS if using GOES). This assessment will build from the assessment from the previous scan (10 min prior) and around hotspot locations. This information (plume locations) would then be available for an operations person in a Regional Control Centre.
Abstract: Since March 2002, the GRACE mission provides monthly global maps of geoid time-variations. These new data carry information on the continental water storage, including snow mass variations, with a ground resolution of ~600-700 km. We have computed monthly snow mass solutions from the inversion of the 22 GRACE geoids (04/2002 - 05/2004). The inverse approach developed here allows to separate the soil waters from snow signal. These snow mass solutions are further compared to predictions from three global land surface models and snow depths derived from satellite microwave data. We find that the GRACE solutions correlate well with the high-latitude zones of strong accumulation of snow. Regional means computed for four large boreal basins (Yenisey, Ob, Mac Kenzie and Yukon) show a good agreement at seasonal scale between the snow mass solutions and model predictions (global rms ~30-40 mm of equivalent-water height and ~10-20 mm regionally).
Abstract: With the recent advent and widespread use of smart mobile devices, the flexibility and versatility offered by Service Oriented Architecture’s (SOA) makes it an ideal approach to use in the rapidly changing mobile environment. However, the mobile setting presents a set of new challenges that service discovery methods developed for non- mobile environments cannot address. The requirements a mobile client device will have from a Web service may change due to changes in the context or the resources of the client device. In a similar manner, a mobile device that acts as a Web service provider will have different capabilities depending on its status, which may also change dramatically during runtime. This paper introduces VOLARE, a middleware-based solution that will monitor the resources and context of the device, and adapt service requests accordingly. The same method will be used to adapt the Quality of Service (QoS) levels advertised by service providers, to realistically reflect each provider’s capabilities at any given moment. This approach will allow for more resource-efficient and accurate service discovery in mobile systems and will enable more reliable provider functionality in mobile devices. Keywords: mobile systems, semantic Web, context awareness, Web services, service discovery, quality of service metrics
In recent years, the researches on the applications of thermal remote sensing of urban areas were mainly in following respects: study on the land surface temperature or the spatial structure of urban thermal pattern and their relationship with surface parameters; urban surface energy balances and fluxes[8,10]; the relationship between atmospheric temperature and land surface temperature. Some studies examined the effect of land use/land cover change on LST[6-7,15], which was found to be positively correlated with impervious surface .Some studies