Study of advanced communications satellite systems based on SS-FDMA

A satellite communication system based on the use of a multiple, contiguous beam satellite antenna and frequency division multiple access (FDMA) is studied. Emphasis is on the evaluation of the feasibility of SS (satellite switching) FDMA technology, particularly the multiple, contiguous beam antenna, the onboard switch and channelization, and on methods to overcome the effects of severe Ka band fading caused by precipitation. This technology is evaluated and plans for technology development and evaluation are given. The application of SS-FDMA to domestic satellite communications is also evaluated. Due to the potentially low cost Earth stations, SS-FDMA is particularly attractive for thin route applications up to several hundred kilobits per second, and offers the potential for competing with terrestrial facilities at low data rates and over short routes. The onboard switch also provides added route flexibility for heavy route systems. The key beneficial SS-FDMA strategy is to simplify and thus reduce the cost of the direct access Earth station at the expense of increased satellite complexity

Communications systems technology assessment study. Volume 2: Results

The cost and technology characteristics are examined for providing special satellite services at UHF, 2.5 GHz, and 14/12 GHz. Considered are primarily health, educational, informational and emergency disaster type services. The total cost of each configuration including space segment, earth station, installation operation and maintenance was optimized to reduce the user's total annual cost and establish preferred equipment performance parameters. Technology expected to be available between now and 1985 is identified and comparisons made between selected alternatives. A key element of the study is a survey of earth station equipment updating past work in the field, providing new insight into technology, and evaluating production and test methods that can reduce costs in large production runs. Various satellite configurations were examined. The cost impact of rain attenuation at Ku-band was evaluated. The factors affecting the ultimate capacity achievable with the available orbital arc and available bandwidth were analyzed

Mobile radio alternative systems study satellite/terrestrial (hybrid) systems concepts

The use of satellites for mobile radio service in non-urban areas of the United States in the years from 1985 to 2000 was investigated. Several satellite concepts are considered: a system with single-beam coverage of the fifty United States and Puerto Rico, and multi-beam satellites with greater capacity. All of the needed functions and services identified in the market study are provided by the satellite systems, including nationwide radio access to vehicles without knowledge of vehicle location wideband data transmission from remote sites, two way exchange of short data and control messages between vehicles and dispatch or control centers, and automatic vehicle location (surveillance). The costs of providing the services are within acceptable limits, and the desired returns to the system investors are attractive. The criteria by which the Federal Communication judges the competing demands for public radio spectrum are reviewed with comments on how the criteria might apply to the consideration of land mobile satellites. Institutional arrangements for operating a mobile satellite system are based on the present institutional arrangements in which the services are offered to the end users through wireline and radio common carriers, with direct access by large private and government users

La construcción de lo médico/científico de la salud en la noticia televisiva en Guatemala: procesos de significación, dominación y legitimación

La presente tesis investiga cuáles son los factores que inciden en el proceso de configuración de la significación que se hace sobre lo médico/científico en la producción de noticias televisivas de salud en Guatemala. El estudio se realiza desde la teoría de la estructuración social, la comunicación pública de la ciencia y desde un enfoque metodológico hermenéutico que aplica el método de análisis formal y el método de análisis semiolingüístico. Se instala en el contexto socio-histórico de Guatemala y parte de la producción, los intercambios, la configuración y re-configuración de sentido que existen entre los agentes sociales vinculados a la noticia de salud, se toma en cuenta que los procesos de significación de la salud están atravesados por una serie de concepciones culturales y estructurales que se han establecido a lo largo de la historia. Asimismo, el estudio atiende lo relacionado con las disputas de poder, la dominación y legitimación que se dan en los procesos de significación de la salud y la ciencia en el proceso de la noticia televisiva de salud. This research thesis discuses television news production in Guatemala into two perspectives: health and science communication. What are the underlying factors regarding the medical/scientific in the news production process of one channel in Guatemala’s television? This work elaborates answers with the Structuration Theory of Anthony Giddens, the Public Communication of science, hermeneutics, formal analysis and semiolinguistics, The current work is framed in Guatemala’s historical and social context where it involves the production process, history, cultural and structural conceptions, power struggles, domination and legitimation processes, which are deeply bonded to the sense making process of the social agents throughout the field

Identity Research and the Psychosocial Formation of One’s Sense of Spiritual Self: Implications for Religious Educators and Christian Institutions of Higher Education

Utilizing Erikson’s (1963) psychosocial ego identity development theory, 28 qualitative interviews with religiously devout Americans are analyzed to determine different patterns of adult spiritual identity. Following an integrationist approach, we provide response to the question, “What types of identity development are accommodated, promoted, or prohibited by particular models of Christian education and the educational communities that embody them?” Recognizing individual differences in (a) the social and contextual factors that affect identity formation, (b) the way religious doubts are resolved, and (c) what individuals seek from community, we offer important implications for religious educators and Christian institutions of higher education

Ontology-Based Data Integration in Multi-Disciplinary Engineering Environments: A Review

Today's industrial production plants are complex mechatronic systems. In the course of the production plant lifecycle, engineers from a variety of disciplines (e.g., mechanics, electronics, automation) need to collaborate in multi-disciplinary settings that are characterized by heterogeneity in terminology, methods, and tools. This collaboration yields a variety of engineering artifacts that need to be linked and integrated, which on the technical level is reflected in the need to integrate heterogeneous data. Semantic Web technologies, in particular ontologybased data integration (OBDI), are promising to tackle this challenge that has attracted strong interest from the engineering research community. This interest has resulted in a growing body of literature that is dispersed across the Semantic Web and Automation System Engineering research communities and has not been systematically reviewed so far. We address this gap with a survey reflecting on OBDI applications in the context of Multi-Disciplinary Engineering Environment (MDEE). To this end, we analyze and compare 23 OBDI applications from both the Semantic Web and the Automation System Engineering research communities. Based on this analysis, we (i) categorize OBDI variants used in MDEE, (ii) identify key problem context characteristics, (iii) compare strengths and limitations of OBDI variants as a function of problem context, and (iv) provide recommendation guidelines for the selection of OBDI variants and technologies for OBDI in MDEE

Identity and Spirituality: A Psychosocial Exploration of the Sense of Spiritual Self

The authors examined the structure and content of adults’ sense of spiritual identity by analyzing semistructured interviews with 13 spiritually devout men and 15 devout women, ages 22 to 72. Individuals’ responses to the Role-Related Identity Interview (G. T. Sorell, M. J. Montgomery, & N. A. Busch-Rossnagel, 1997b) were content analyzed and rated on the role-related spiritual identity dimensions of role salience and flexibility. Individuals were categorized as spiritually foreclosed, achieved, or in moratorium, on the basis of their motivational, affective, self-evaluative, and behavioral investments in spiritually defined roles and their reflectiveness about and behavioral changes in role-related spiritual identity. Similarities and differences within and between spiritual identity status groups were observed, suggesting a variety of ways that spiritual identity provides a sense of continuity as well as a domain for adult developmental change