Isolated lower mesospheric echoes seen by medium frequency radar at 70 N, 19 E C. M. Hall, A. H. Manson, C. E. Meek, and S. Nozawa Tromsø Geophysical Observatory, University of Tromsø, Tromsø, Norway Institute of Space and Atmospheric Studies,University of Saskatchewan, Saskatoon, Canada The Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, Japan Received: 16 June 2006 – Acce...

A public process has been in place in the United States for six years to establish an HDTV terrestrial broadcasting standard. The process, having moved through a planning phase, a competition phase, and an examination phase, has now entered a cooperation phase. Remarkable progress has been made — a testament to the process. During the next few months, the American digital HDTV terrestrial broad...

background: natural radioactivity in materials under certain conditions can reach the hazardous radiological levels. so, it becomes necessary to study the natural radioactivity in different materials to assess the dose for the population in order to know the health risks and to have a baseline for future changes in the environmental radioactivity due to human activities. materials and methods: ...

Radiation may be defined as the energy in form of electromagnetic waves or particles that pass through space and even heavy dense materials. The radioactivity is a continuously decreasing quantity which function half-life responsible radionuclides. natural sources radiation came from terrestrial radionuclides are widely distributed earth's crust. Field radiological surveys were conducted by GR-...

natural radionuclides present in soil as well as certain anthropogenic radionuclides released to the environment are the major contributors to terrestrial outdoor exposures. in the assessment of human exposures from environmental radioactivity, besides the conventional method of soil and vegetation sampling combined with laboratory based analyses of environmental media, the other choice would b...

background: the aims of the study are to determine the radioactivity concentrations of 226ra, 238u, 232th and 40k in vegetables of a recently found high background radiation area of south-eastern part of bangladesh and to detect the radiological risks to human from intake of these vegetables. materials and method: 10 plant samples were collected randomly from different locations of the study ar...

In this paper a comparative study of two measurement campaigns carried out in Barcelona, Spain, and Pozna , Poland, to identify spectrum occupancy in different bands, is presented. In both cases the measurement setup was harmonized to obtain comparable results. The problem of efficient noise floor estimation was also considered and a pragmatic approach that takes into account both internal and ...

The present study introduces some data regarding Radiation Doses Due to Natural Radioactivity measured the investigations we have already carried out in Selected Areas in Southern Part of Jordan. The investigated area, which is 270 Km long, includes three governorates in Jordan: Tafila, Ma'an, and Aqaba. These data emphasis on new findings of different radiation dose rates, to mainly identify t...

Background: The concentrations and distributions of natural and anthropogenic radioactive materials in soils of the site of Rooppur Nuclear Power Plant (RNPP) were investigated with the aim of evaluating the environmental radioactivity and radiation hazard. Materials and Methods: Soil samples were collected from 40 locations in and around the proposed site of Rooppur Power Plant and determined ...