WorldWideScience

Sample records for base station radiofrequency

  1. Survey of radiofrequency radiation levels around GSM base stations and evaluation of measurement uncertainty

    International Nuclear Information System (INIS)

    This paper is a summary of broadband measurement values of radiofrequency radiation around GSM base stations in the vicinity of residential areas in Belgrade and 12 other cities in Serbia. It will be useful for determining non-ionizing radiation exposure levels of the general public in the future. The purpose of this paper is also an appropriate representation of basic information on the evaluation of measurement uncertainty. (author)

  2. Assessment of radiofrequency/microwave radiation emitted by the antennas of rooftop-mounted mobile phone base stations

    International Nuclear Information System (INIS)

    Radiofrequency (RF) and microwave (MW) radiation exposures from the antennas of rooftop-mounted mobile telephone base stations have become a serious issue in recent years due to the rapidly evolving technologies in wireless telecommunication systems. In Malaysia, thousands of mobile telephone base stations have been erected all over the country, most of which are mounted on the rooftops. In view of public concerns, measurements of the RF/MW levels emitted by the base stations were carried out in this study. The values were compared with the exposure limits set by several organisations and countries. Measurements were performed at 200 sites around 47 mobile phone base stations. It was found that the RF/MW radiation from these base stations were well below the maximum exposure limits set by various agencies. (authors)

  3. Study of variations of radiofrequency power density from mobile phone base stations with distance

    International Nuclear Information System (INIS)

    The variations of radiofrequency (RF) radiation power density with distance around some mobile phone base stations (BTSs), in ten randomly selected locations in Ibadan, western Nigeria, were studied. Measurements were made with a calibrated hand-held spectrum analyser. The maximum Global System of Mobile (GSM) communication 1800 signal power density was 323.91 μW m-2 at 250 m radius of a BTS and that of GSM 900 was 1119.00 μW m-2 at 200 m radius of another BTS. The estimated total maximum power density was 2972.00 μW m-2 at 50 m radius of a different BTS. This study shows that the maximum carrier signal power density and the total maximum power density from a BTS may be observed averagely at 200 and 50 m of its radius, respectively. The result of this study demonstrates that exposure of people to RF radiation from phone BTSs in Ibadan city is far less than the recommended limits by International scientific bodies. (authors)

  4. Measurement and analysis of radiofrequency radiations from some mobile phone base stations in Ghana

    International Nuclear Information System (INIS)

    A survey of the radiofrequency electromagnetic radiation at public access points in the vicinity of 50 cellular phone base stations has been carried out. The primary objective was to measure and analyse the electromagnetic field strength levels emitted by antennae installed and operated by the Ghana Telecommunications Company. On all the sites measurements were made using a hand-held spectrum analyser to determine the electric field level with the 900 and 1800 MHz frequency bands. The results indicated that power densities at public access points varied from as low as 0.01 μW m-2 to as high as 10 μW m-2 for the frequency of 900 MHz. At a transmission frequency of 1800 MHz, the variation of power densities is from 0.01 to 100 μW m-2. The results were found to be in compliant with the International Commission on Non-ionizing Radiological Protection guidance level but were 20 times higher than the results generally obtained for such a practice elsewhere. There is therefore a need to re-assess the situation to ensure reduction in the present level as an increase in mobile phone usage is envisaged within the next few years. (authors)

  5. Animal carcinogenicity studies on radiofrequency fields related to mobile phones and base stations

    International Nuclear Information System (INIS)

    Since a report in 1997 on an increased lymphoma incidence in mice chronically exposed to a mobile phone radiofrequency signal, none of the subsequent long-term studies in rodents have confirmed these results. On the other hand, several of the follow-up co- and carcinogenicity studies are still underway or are presently being initiated. Most of the published long-term studies used 1 exposure level only and suffer from a poor dosimetry which does not consider the animal's growth. Additional points of criticism are a limited, in some cases, questionable histopathology and inadequate group sizes. Overall, if dealing with new chemicals or drugs, these studies would not be acceptable for registration with the responsible authorities. The major critical points are taken into consideration within the European co- and carcinogenicity projects (CEMFEC and PERFORM-A), which are in their final stages and in the US long-term studies in mice and rats which are about to be initiated. Nevertheless, the WHO evaluation for health risk assessment of long-term telephone use and base station exposure will start in late 2005

  6. Assessment of Radio-Frequency Radiation Exposure Level from Selected Mobile Base Stations (MBS) in Lokoja, Kogi State, Nigeria

    CERN Document Server

    Victor, U J Nwankwo; Dada, S S; Onugba, A A; Ushie, P

    2012-01-01

    The acquisition and use of mobile phone is tremendously increasing especially in developing countries, but not without a concern. The greater concern among the public is principally over the proximity of mobile base stations (MBS) to residential areas rather than the use of handsets. In this paper, we present an assessment of Radio-Frequency (RF) radiation exposure level measurements and analysis of radiation power density (in \\mu W/sq m) from mobile base stations relative to radial distance (in metre). The minimum average power density from individual base station in the town was about 47\\mu W/sq m while the average maximum was about 1.5mW/sq m. Our result showed that average power density of a base station decreases with increase in distance (from base station) and that radiation intensity varies from one base station to another even at the same distance away. Our result (obtained signature of power density variation) was also compared with the 'expected' signature. It was found that radiation from external...

  7. Assessment of radiofrequency radiation within the vicinity of some GSM base stations in Ghana

    International Nuclear Information System (INIS)

    A radiofrequency (RF) electromagnetic radiation safety survey had been carried out at public access points in 46 towns with 76 Global Systems for Mobile communication cell sites in two major cities in Ghana. The objective was to determine the levels of RF field in residential areas, schools and market places, and compare the measured results with the guidelines set by the International Commission of Non-Ionising Radiation (ICNIRP). Measurements were made with log-periodic antenna coupled with spectrum analyzer. The results varied from 0.85 to 1.07 mW m-2 and 0.78 to 1.19 mW m-2 for the transmission frequencies of 900 and 1800 MHz, respectively. The result generally shows a compliance with the ICNIRP limit of 0.024 % but was 108 times higher than a similar survey carried out in Ghana 2 y ago. (authors)

  8. Measurement and Analysis of Radio-frequency Radiation Exposure Level from Different Mobile Base Transceiver Stations in Ajaokuta and Environs, Nigeria

    OpenAIRE

    Ushie, P. O.; Nwankwo, Victor U. J.; Bolaji, Ayinmode; Osahun, O. D.

    2013-01-01

    We present the result of a preliminary assessment of radio-frequency radiation exposure from selected mobile base stations in Ajaokuta environs. The Power density of RF radiation within a radial distance of 125m was measured. Although values fluctuated due to the influence of other factors, including wave interference from other electromagnetic sources around reference base stations, we show from analysis that radiation exposure level is below the standard limit (4.5W/sqm for 900MHz and 9W/sq...

  9. Measurement and Analysis of Radio-frequency Radiation Exposure Level from Different Mobile Base Transceiver Stations in Ajaokuta and Environs, Nigeria

    CERN Document Server

    Ushie, P O; Bolaji, Ayinmode; Osahun, O D

    2013-01-01

    We present the result of a preliminary assessment of radio-frequency radiation exposure from selected mobile base stations in Ajaokuta environs. The Power density of RF radiation within a radial distance of 125m was measured. Although values fluctuated due to the influence of other factors, including wave interference from other electromagnetic sources around reference base stations, we show from analysis that radiation exposure level is below the standard limit (4.5W/sqm for 900MHz and 9W/sqm for 18000MHz) set by the International Commission on Non-ionizing Radiation Protection (ICNIRP) and other regulatory agencies.

  10. Comparative studies of the ITU-T prediction model for radiofrequency radiation emission and real time measurements at some selected mobile base transceiver stations in Accra, Ghana

    International Nuclear Information System (INIS)

    Recent developments in the electronics industry have led to the widespread use of radiofrequency (RF) devices in various areas including telecommunications. The increasing numbers of mobile base station (BTS) as well as their proximity to residential areas have been accompanied by public health concerns due to the radiation exposure. The main objective of this research was to compare and modify the ITU- T predictive model for radiofrequency radiation emission for BTS with measured data at some selected cell sites in Accra, Ghana. Theoretical and experimental assessment of radiofrequency exposures due to mobile base station antennas have been analysed. The maximum and minimum average power density measured from individual base station in the town was 1. 86µW/m2 and 0.00961µW/m2 respectively. The ITU-T Predictive model power density ranged between 6.40mW/m2 and 0.344W/m2. Results obtained showed a variation between measured power density levels and the ITU-T predictive model. The ITU-T model power density levels decrease with increase in radial distance while real time measurements do not due to fluctuations during measurement. The ITU-T model overestimated the power density levels by a factor l05 as compared to real time measurements. The ITU-T model was modified to reduce the level of overestimation. The result showed that radiation intensity varies from one base station to another even at the same distance. Occupational exposure quotient ranged between 5.43E-10 and 1.89E-08 whilst general public exposure quotient ranged between 2.72E-09 and 9.44E-08. From the results, it shows that the RF exposure levels in Accra from these mobile phone base station antennas are below the permitted RF exposure limit to the general public recommended by the International Commission on Non-Ionizing Radiation Protection. (au)

  11. Radiofrequency electromagnetic fields emitted from base stations of DECT cordless phones and the risk of glioma and meningioma (Interphone Study Group, Germany)

    DEFF Research Database (Denmark)

    Schüz, Joachim; Böhler, Eva; Schlehofer, Brigitte;

    2006-01-01

    cellular phone use were 747 incident brain tumor cases between the ages of 30 and 69 years and 1494 matched controls. The exposure measure of this analysis was the location of a base station of a DECT (Digital Enhanced Cordless Telecommunications) cordless phone close to the bed, which was used as a proxy...... for continuous low-level exposure to RF EMFs during the night. Estimated odds ratios were 0.82 (95% confidence interval: 0.29-2.33) for glioma and 0.83 (0.29-2.36) for meningioma. There was also no increasing risk observed with duration of exposure to DECT cordless phone base stations. Although the...

  12. Response to Comments on Meo et al. Association of Exposure to Radio-Frequency Electromagnetic Field Radiation (RF-EMFR Generated by Mobile Phone Base Stations with Glycated Hemoglobin (HbA1c and Risk of Type 2 Diabetes Mellitus. Int. J. Environ. Res. Public Health, 2015, 12, 14519–14528

    Directory of Open Access Journals (Sweden)

    Sultan Ayoub Meo

    2016-02-01

    Full Text Available We highly appreciate the readers’ interest [1] in our article [2] titled “Association of Exposure to Radio-Frequency Electromagnetic Field Radiation (RF-EMFR Generated by Mobile Phone Base Stations with Glycated Hemoglobin (HbA1c and Risk of Type 2 Diabetes Mellitus” published in the International Journal of Environmental Research and Public Health [2].[...

  13. Response to Comments on Meo et al. Association of Exposure to Radio-Frequency Electromagnetic Field Radiation (RF-EMFR) Generated by Mobile Phone Base Stations with Glycated Hemoglobin (HbA1c) and Risk of Type 2 Diabetes Mellitus. Int. J. Environ. Res. Public Health, 2015, 12, 14519–14528

    OpenAIRE

    Sultan Ayoub Meo; Yazeed Alsubaie; Zaid Almubarak; Hisham Almutawa; Yazeed AlQasem; Rana Muhammed Hasanato

    2016-01-01

    We highly appreciate the readers’ interest [1] in our article [2] titled “Association of Exposure to Radio-Frequency Electromagnetic Field Radiation (RF-EMFR) Generated by Mobile Phone Base Stations with Glycated Hemoglobin (HbA1c) and Risk of Type 2 Diabetes Mellitus” published in the International Journal of Environmental Research and Public Health [2].[...

  14. Secure base stations

    NARCIS (Netherlands)

    Bosch, Peter; Brusilovsky, Alec; McLellan, Rae; Mullender, Sape; Polakos, Paul

    2009-01-01

    With the introduction of the third generation (3G) Universal Mobile Telecommunications System (UMTS) base station router (BSR) and fourth generation (4G) base stations, such as the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) Evolved Node B (eNB), it has become important to se

  15. A comparative study of radiofrequency emission from roof top mobile phone base station antennas and tower mobile phone base antennas located at some selected cell sites in Accra, Ghana

    International Nuclear Information System (INIS)

    RF radiation exposure from antennas mounted on rooftop mobile phone base stations have become a serious issue in recent years due to the rapidly developing technologies in wireless telecommunication. The heightening numbers of base station and their closeness to the general public has led to possible health concerns as a result of exposure to RF radiations. The primary objective of this study was to assess the level of RF radiation emitted from roof top mobile phone base station antennas and compare the measured results with the guidelines set by International Commission on Non-ionization Radiation. The maximum and minimum average power density measured from the rooftop sites inside buildings were 2.46xI0-2 and 1.68x10-3 W/m2 respectively whereas that for outside buildings at the same rooftop site was also 7.44x 10-5 and 3.35x 10-3 W/m2 respectively. Public exposure quotient also ranged between 3.74x10-10 to 1.31x10-07 inside buildings whilst that for outside varied between 7.44x 10-10 to 1.65x 10-06. Occupational exposure quotient inside buildings varied between 1.66x 10-11 to 2.11 x 10-09 whereas that for outside ranged from 3.31x10-09 to 3.30x10-07 all at the rooftop site. The results obtained for a typical tower base station also indicated that the maximum and minimum average power density was 4.57x10-1 W/m2 and 7.13x10-3 W/m2 respectively. The public exposure quotient varied between 1.58x10-09 to 1.01x10-07 whilst that for occupational exposure quotient ranged between 3.17x10-10 to 2.03x10-08. The values of power densities levels inside buildings at rooftop sites are low compared to that of tower sites. This could be due to high attenuation caused by thick concrete walls and ceilings. The results obtained were found to be in compliance with ICNIRP and FCC guidance levels of 4.5 W/m2 and 6 W/m2 respectively. (au)

  16. Assessment of outdoor radiofrequency electromagnetic field exposure through hotspot localization using kriging-based sequential sampling.

    Science.gov (United States)

    Aerts, Sam; Deschrijver, Dirk; Verloock, Leen; Dhaene, Tom; Martens, Luc; Joseph, Wout

    2013-10-01

    In this study, a novel methodology is proposed to create heat maps that accurately pinpoint the outdoor locations with elevated exposure to radiofrequency electromagnetic fields (RF-EMF) in an extensive urban region (or, hotspots), and that would allow local authorities and epidemiologists to efficiently assess the locations and spectral composition of these hotspots, while at the same time developing a global picture of the exposure in the area. Moreover, no prior knowledge about the presence of radiofrequency radiation sources (e.g., base station parameters) is required. After building a surrogate model from the available data using kriging, the proposed method makes use of an iterative sampling strategy that selects new measurement locations at spots which are deemed to contain the most valuable information-inside hotspots or in search of them-based on the prediction uncertainty of the model. The method was tested and validated in an urban subarea of Ghent, Belgium with a size of approximately 1 km2. In total, 600 input and 50 validation measurements were performed using a broadband probe. Five hotspots were discovered and assessed, with maximum total electric-field strengths ranging from 1.3 to 3.1 V/m, satisfying the reference levels issued by the International Commission on Non-Ionizing Radiation Protection for exposure of the general public to RF-EMF. Spectrum analyzer measurements in these hotspots revealed five radiofrequency signals with a relevant contribution to the exposure. The radiofrequency radiation emitted by 900 MHz Global System for Mobile Communications (GSM) base stations was always dominant, with contributions ranging from 45% to 100%. Finally, validation of the subsequent surrogate models shows high prediction accuracy, with the final model featuring an average relative error of less than 2dB (factor 1.26 in electric-field strength), a correlation coefficient of 0.7, and a specificity of 0.96. PMID:23759207

  17. Applicability of an exposure model for the determination of emissions from mobile phone base stations

    DEFF Research Database (Denmark)

    Breckenkamp, J; Neitzke, H P; Bornkessel, C;

    2008-01-01

    Applicability of a model to estimate radiofrequency electromagnetic field (RF-EMF) strength in households from mobile phone base stations was evaluated with technical data of mobile phone base stations available from the German Net Agency, and dosimetric measurements, performed in an...

  18. Association of Exposure to Radio-Frequency Electromagnetic Field Radiation (RF-EMFR) Generated by Mobile Phone Base Stations with Glycated Hemoglobin (HbA1c) and Risk of Type 2 Diabetes Mellitus

    Science.gov (United States)

    Meo, Sultan Ayoub; Alsubaie, Yazeed; Almubarak, Zaid; Almutawa, Hisham; AlQasem, Yazeed; Muhammed Hasanato, Rana

    2015-01-01

    Installation of mobile phone base stations in residential areas has initiated public debate about possible adverse effects on human health. This study aimed to determine the association of exposure to radio frequency electromagnetic field radiation (RF-EMFR) generated by mobile phone base stations with glycated hemoglobin (HbA1c) and occurrence of type 2 diabetes mellitus. For this study, two different elementary schools (school-1 and school-2) were selected. We recruited 159 students in total; 96 male students from school-1, with age range 12–16 years, and 63 male students with age range 12–17 years from school-2. Mobile phone base stations with towers existed about 200 m away from the school buildings. RF-EMFR was measured inside both schools. In school-1, RF-EMFR was 9.601 nW/cm2 at frequency of 925 MHz, and students had been exposed to RF-EMFR for a duration of 6 h daily, five days in a week. In school-2, RF-EMFR was 1.909 nW/cm2 at frequency of 925 MHz and students had been exposed for 6 h daily, five days in a week. 5–6 mL blood was collected from all the students and HbA1c was measured by using a Dimension Xpand Plus Integrated Chemistry System, Siemens. The mean HbA1c for the students who were exposed to high RF-EMFR was significantly higher (5.44 ± 0.22) than the mean HbA1c for the students who were exposed to low RF-EMFR (5.32 ± 0.34) (p = 0.007). Moreover, students who were exposed to high RF-EMFR generated by MPBS had a significantly higher risk of type 2 diabetes mellitus (p = 0.016) relative to their counterparts who were exposed to low RF-EMFR. It is concluded that exposure to high RF-EMFR generated by MPBS is associated with elevated levels of HbA1c and risk of type 2 diabetes mellitus. PMID:26580639

  19. Association of Exposure to Radio-Frequency Electromagnetic Field Radiation (RF-EMFR Generated by Mobile Phone Base Stations with Glycated Hemoglobin (HbA1c and Risk of Type 2 Diabetes Mellitus

    Directory of Open Access Journals (Sweden)

    Sultan Ayoub Meo

    2015-11-01

    Full Text Available Installation of mobile phone base stations in residential areas has initiated public debate about possible adverse effects on human health. This study aimed to determine the association of exposure to radio frequency electromagnetic field radiation (RF-EMFR generated by mobile phone base stations with glycated hemoglobin (HbA1c and occurrence of type 2 diabetes mellitus. For this study, two different elementary schools (school-1 and school-2 were selected. We recruited 159 students in total; 96 male students from school-1, with age range 12–16 years, and 63 male students with age range 12–17 years from school-2. Mobile phone base stations with towers existed about 200 m away from the school buildings. RF-EMFR was measured inside both schools. In school-1, RF-EMFR was 9.601 nW/cm2 at frequency of 925 MHz, and students had been exposed to RF-EMFR for a duration of 6 h daily, five days in a week. In school-2, RF-EMFR was 1.909 nW/cm2 at frequency of 925 MHz and students had been exposed for 6 h daily, five days in a week. 5–6 mL blood was collected from all the students and HbA1c was measured by using a Dimension Xpand Plus Integrated Chemistry System, Siemens. The mean HbA1c for the students who were exposed to high RF-EMFR was significantly higher (5.44 ± 0.22 than the mean HbA1c for the students who were exposed to low RF-EMFR (5.32 ± 0.34 (p = 0.007. Moreover, students who were exposed to high RF-EMFR generated by MPBS had a significantly higher risk of type 2 diabetes mellitus (p = 0.016 relative to their counterparts who were exposed to low RF-EMFR. It is concluded that exposure to high RF-EMFR generated by MPBS is associated with elevated levels of HbA1c and risk of type 2 diabetes mellitus.

  20. Radiofrequency fields: Bases for exposure limits

    International Nuclear Information System (INIS)

    Several biological effects have been reported at exposure levels below the threshold for thermal effects, but most of them require independent confirmation before being accepted as established. However, no seems to have relevant implications for human health. Precautionary measures should be based on a cost/benefit analysis, and be proportionate on one side to the risk they aim at preventing and on the other side to actions taken in other areas to prevent comparable risks. (N.C.)

  1. Radiofrequency fields: Bases for exposure limits

    Energy Technology Data Exchange (ETDEWEB)

    Paolo Vecchia [Department of Technologies and Health National Institute of Health, Rome (Italy)

    2006-07-01

    Several biological effects have been reported at exposure levels below the threshold for thermal effects, but most of them require independent confirmation before being accepted as established. However, no seems to have relevant implications for human health. Precautionary measures should be based on a cost/benefit analysis, and be proportionate on one side to the risk they aim at preventing and on the other side to actions taken in other areas to prevent comparable risks. (N.C.)

  2. Assessment of outdoor radiofrequency electromagnetic field exposure through hotspot localization using kriging-based sequential sampling

    Energy Technology Data Exchange (ETDEWEB)

    Aerts, Sam, E-mail: sam.aerts@intec.ugent.be; Deschrijver, Dirk; Verloock, Leen; Dhaene, Tom; Martens, Luc; Joseph, Wout

    2013-10-15

    In this study, a novel methodology is proposed to create heat maps that accurately pinpoint the outdoor locations with elevated exposure to radiofrequency electromagnetic fields (RF-EMF) in an extensive urban region (or, hotspots), and that would allow local authorities and epidemiologists to efficiently assess the locations and spectral composition of these hotspots, while at the same time developing a global picture of the exposure in the area. Moreover, no prior knowledge about the presence of radiofrequency radiation sources (e.g., base station parameters) is required. After building a surrogate model from the available data using kriging, the proposed method makes use of an iterative sampling strategy that selects new measurement locations at spots which are deemed to contain the most valuable information—inside hotspots or in search of them—based on the prediction uncertainty of the model. The method was tested and validated in an urban subarea of Ghent, Belgium with a size of approximately 1 km{sup 2}. In total, 600 input and 50 validation measurements were performed using a broadband probe. Five hotspots were discovered and assessed, with maximum total electric-field strengths ranging from 1.3 to 3.1 V/m, satisfying the reference levels issued by the International Commission on Non-Ionizing Radiation Protection for exposure of the general public to RF-EMF. Spectrum analyzer measurements in these hotspots revealed five radiofrequency signals with a relevant contribution to the exposure. The radiofrequency radiation emitted by 900 MHz Global System for Mobile Communications (GSM) base stations was always dominant, with contributions ranging from 45% to 100%. Finally, validation of the subsequent surrogate models shows high prediction accuracy, with the final model featuring an average relative error of less than 2 dB (factor 1.26 in electric-field strength), a correlation coefficient of 0.7, and a specificity of 0.96. -- Highlights: • We present an

  3. Assessment of outdoor radiofrequency electromagnetic field exposure through hotspot localization using kriging-based sequential sampling

    International Nuclear Information System (INIS)

    In this study, a novel methodology is proposed to create heat maps that accurately pinpoint the outdoor locations with elevated exposure to radiofrequency electromagnetic fields (RF-EMF) in an extensive urban region (or, hotspots), and that would allow local authorities and epidemiologists to efficiently assess the locations and spectral composition of these hotspots, while at the same time developing a global picture of the exposure in the area. Moreover, no prior knowledge about the presence of radiofrequency radiation sources (e.g., base station parameters) is required. After building a surrogate model from the available data using kriging, the proposed method makes use of an iterative sampling strategy that selects new measurement locations at spots which are deemed to contain the most valuable information—inside hotspots or in search of them—based on the prediction uncertainty of the model. The method was tested and validated in an urban subarea of Ghent, Belgium with a size of approximately 1 km2. In total, 600 input and 50 validation measurements were performed using a broadband probe. Five hotspots were discovered and assessed, with maximum total electric-field strengths ranging from 1.3 to 3.1 V/m, satisfying the reference levels issued by the International Commission on Non-Ionizing Radiation Protection for exposure of the general public to RF-EMF. Spectrum analyzer measurements in these hotspots revealed five radiofrequency signals with a relevant contribution to the exposure. The radiofrequency radiation emitted by 900 MHz Global System for Mobile Communications (GSM) base stations was always dominant, with contributions ranging from 45% to 100%. Finally, validation of the subsequent surrogate models shows high prediction accuracy, with the final model featuring an average relative error of less than 2 dB (factor 1.26 in electric-field strength), a correlation coefficient of 0.7, and a specificity of 0.96. -- Highlights: • We present an iterative

  4. Assessment of levels of occupational exposure to workers in radiofrequency fields of two television stations in Accra, Ghana.

    Science.gov (United States)

    Osei, S; Amoako, J K; Fletcher, J J

    2016-03-01

    A survey of the radiofrequency (RF) radiation was undertaken within the premises of two television (TV) stations, TVA and TVB, in Accra, Ghana. The primary objective of this study was to determine the level of RF exposure to workers in the TV stations. A spectrum analyser, a bi-conical antenna (30-300 MHz) and a log-periodic antenna (200 MHz-2.0 GHz) were used. Results obtained indicated that the wideband electric field strength levels recorded in this work vary between 0.006 and 58.5 V m(-1) at TVA and between 0.007 and 28.5 V m(-1) at TVB. Compared with the results from TVB, TVA recorded relatively higher values in the 30-400 MHz range, whereas TVB produced relatively higher values in the 400 MHz-1.7 GHz range. Generally, results obtained were found to be below the occupational reference levels of the International Commission on Non-Ionizing Radiation Protection, but at some locations, the field intensity was 4.3 times higher than the reference levels for the general public. PMID:25979743

  5. Assessment of levels of occupational exposure to workers in radiofrequency fields of two television stations in Accra, Ghana

    International Nuclear Information System (INIS)

    A survey of the radiofrequency (RF) radiation was undertaken within the premises of two television (TV) stations, TVA and TVB, in Accra, Ghana. The primary objective of this study was to determine the level of RF exposure to workers in the TV stations. A spectrum analyser, a bi-conical antenna (30-300 MHz) and a log-periodic antenna (200 MHz-2.0 GHz) were used. Results obtained indicated that the wideband electric field strength levels recorded in this work vary between 0.006 and 58.5 V m-1 at TVA and between 0.007 and 28.5 V m-1 at TVB. Compared with the results from TVB, TVA recorded relatively higher values in the 30-400 MHz range, whereas TVB produced relatively higher values in the 400 MHz-1.7 GHz range. Generally, results obtained were found to be below the occupational reference levels of the International Commission on Non-Ionizing Radiation Protection, but at some locations, the field intensity was 4.3 times higher than the reference levels for the general public. (authors)

  6. Slotted Aloha for Networked Base Stations

    OpenAIRE

    Bajovic, Dragana; Jakovetic, Dusan; Vukobratovic, Dejan; Crnojevic, Vladimir

    2014-01-01

    We study multiple base station, multi-access systems in which the user-base station adjacency is induced by geographical proximity. At each slot, each user transmits (is active) with a certain probability, independently of other users, and is heard by all base stations within the distance $r$. Both the users and base stations are placed uniformly at random over the (unit) area. We first consider a non-cooperative decoding where base stations work in isolation, but a user is decoded as soon as...

  7. Radiation safety assessment of mobile telephone base stations

    International Nuclear Information System (INIS)

    Mobile telephone is fast getting popular among users and in fact it has become one of the fastest selling electronic products in the world. More base stations are expected to be built to meet such high demands and this has caused great concerned among members of the public, especially those living close to the stations, about the potential harmful health effects of radiofrequency (RF) radiation produced by such facilities. A project was initiated by MINT in early 2000 with aims to assess the radiation levels present in the areas around the base stations and to establish baseline data on the pattern and trend of the radiation emission from each different set up of the facilities. This paper highlights some basics facts about mobile telephones and preliminary findings of the project. The assessment has been carried out at 16 base station sites and the results indicate that the radiation levels present around these sites are very low. Their broadband readings vary between below the detection limit of 0.3μWatts/cm2 to 11 μWatts/cm2 and they are comparable to normal background radiation present in places away from any base stations. The highest level observed was 1.5% of the exposure limit recommended for members of the public. However, locations at close distance in front of the the antenna can be very serious in term of radiation exposure since the radiation level here can easily exceed the permissible exposure limit for public. Safety precaution needs to be taken when entering these areas and they should be out of bound for members of the public. (Author)

  8. UMTS Base Station-like Exposure, Well-Being, and Cognitive Performance

    OpenAIRE

    Regel, Sabine J.; Negovetic, Sonja; Röösli, Martin; Berdiñas, Veronica; Schuderer, Jürgen; Huss, Anke; Lott, Urs; KUSTER, Niels; Achermann, Peter

    2006-01-01

    Background Radio-frequency electromagnetic fields (RF EMF) of mobile communication systems are widespread in the living environment, yet their effects on humans are uncertain despite a growing body of literature. Objectives We investigated the influence of a Universal Mobile Telecommunications System (UMTS) base station-like signal on well-being and cognitive performance in subjects with and without self-reported sensitivity to RF EMF. Methods We performed a controlled exposure experiment (45...

  9. Statistical analysis of electromagnetic radiation measurements in the vicinity of indoor microcell GSM/UMTS base stations in Serbia.

    Science.gov (United States)

    Koprivica, Mladen; Petrić, Majda; Nešković, Nataša; Nešković, Aleksandar

    2016-01-01

    To determine the level of radiofrequency radiation generated by base stations of Global System for Mobile Communications and Universal Mobile Telecommunication System, extensive electromagnetic field strength measurements were carried out in the vicinity of 664 base station locations. These were classified into three categories: indoor, masts, and locations with installations on buildings. Although microcell base stations with antennas installed indoors typically emit less power than outdoor macrocell base stations, the fact that people can be found close to antennas requires exposure originating from these base stations to be carefully considered. Measurement results showed that maximum recorded value of electric field strength exceeded International Commission on Non-Ionizing Radiation Protection reference levels at 7% of indoor base station locations. At the same time, this percentage was much lower in the case of masts and installations on buildings (0% and 2.5%, respectively). PMID:26661841

  10. Design, Construction and Operation of a Low-Power, Autonomous Radio-Frequency Data-Acquisition Station for the TARA Experiment

    CERN Document Server

    Kunwar, S; Allen, C; Belz, J; Besson, D; Byrne, M; Farhang-Boroujeny, B; Gillman, W H; Hanlon, W; Hanson, J; Myers, I; Novikov, A; Prohira, S; Ratzlaff, K; Rezazadeh, A; Sanivarapu, V; Schurig, D; Shustov, A; Smirnova, M; Takai, H; Thomson, G B; Young, R

    2015-01-01

    Employing a 40-kW radio-frequency transmitter just west of Delta, UT, and operating at 54.1 MHz, the TARA (Telescope Array RAdar) experiment seeks radar detection of extensive air showers (EAS) initiated by ultra-high energy cosmic rays (UHECR). For UHECR with energies in excess of $10^{19}$ eV, the Doppler-shifted "chirps" resulting from EAS shower core radar reflections should be observable above background (dominantly galactic) at distances of tens of km from the TARA transmitter. In order to stereoscopically reconstruct cosmic ray chirps, two remote, autonomous self-powered receiver stations have been deployed. Each remote station (RS) combines both low power consumption as well as low cost. Triggering logic, the powering and communication systems, and some specific details of hardware components are discussed.

  11. Design, construction and operation of a low-power, autonomous radio-frequency data-acquisition station for the TARA experiment

    Science.gov (United States)

    Kunwar, S.; Abbasi, R.; Allen, C.; Belz, J.; Besson, D.; Byrne, M.; Farhang-Boroujeny, B.; Gillman, W. H.; Hanlon, W.; Hanson, J.; Myers, I.; Novikov, A.; Prohira, S.; Ratzlaff, K.; Rezazadeh, A.; Sanivarapu, V.; Schurig, D.; Shustov, A.; Smirnova, M.; Takai, H.; Thomson, G. B.; Young, R.

    2015-10-01

    Employing a 40-kW, 54.1 MHz radio-frequency transmitter just west of Delta, UT, the TARA (Telescope Array RAdar) experiment seeks radar detection of extensive air showers (EAS) initiated by ultra-high energy cosmic rays (UHECR). For UHECR with energies in excess of 1019 eV, the Doppler-shifted "chirps" resulting from EAS shower core radar reflections should be observable above background (dominantly galactic) at distances of tens of km from the TARA transmitter. In order to stereoscopically reconstruct cosmic ray chirps, two remote, autonomous self-powered receiver stations have been deployed. Each remote station (RS) combines both low power consumption and low cost. Triggering logic, the powering and communication systems, and some specific details of hardware components are discussed.

  12. DMA Reference Base Station Network Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data (15,904 records documenting 9,090 worldwide gravity base stations) were gathered by various governmental organizations (and academia) using a variety of...

  13. Statistical analysis of electromagnetic radiation measurements in the vicinity of GSM/UMTS base station antenna masts

    International Nuclear Information System (INIS)

    As a result of dense installations of public mobile base station, additional electromagnetic radiation occurs in the living environment. In order to determine the level of radio-frequency radiation generated by base stations, extensive electromagnetic field strength measurements were carried out for 664 base station locations. Base station locations were classified into three categories: indoor, masts and locations with installations on buildings. Having in mind the large percentage (47 %) of sites with antenna masts, a detailed analysis of this location category was performed, and the measurement results were presented. It was concluded that the total electric field strength in the vicinity of base station antenna masts in no case exceeded 10 V m-1, which is quite below the International Commission on Non-Ionizing Radiation Protection reference levels. At horizontal distances >50 m from the mast bottom, the median and maximum values were -1, respectively. (authors)

  14. Sensitivity of a micromechanical displacement detector based on the radio-frequency single-electron transistor

    OpenAIRE

    Blencowe, Miles P.; Wybourne, Martin N.

    2000-01-01

    We investigate the tunneling shot noise limits on the sensitivity of a micromechanical displacement detector based on a metal junction, radio-frequency single-electron transistor (rf-SET). In contrast with the charge sensitivity of the rf-SET electrometer, the displacement sensitivity improves with increasing gate voltage bias and, with a suitably optimized rf-SET, displacement sensitivities of $10^{-6} {\\rm\\AA}/\\sqrt{\\rm Hz}$ may be possible.

  15. Are Balloon Based Strategies Better Than Conventional Radiofrequency Catheter Ablation: Exploring New Frontiers In The Treatment Of Atrial Fibrillation

    Directory of Open Access Journals (Sweden)

    Alexander Fuernkranz MD

    2009-02-01

    Full Text Available Paroxysmal atrial fibrillation can be eliminated with continuous circular linear lesions around the pulmonary veins using radiofrequency ablation. Due to the technical complexity of this procedure balloon-based devices have been developed to simplify pulmonary vein isolation. Cryoballoon ablation provides excellent safety and is technically less demanding when compared to radiofrequency catheter ablation in selected patients. In this review, advantages as well as drawbacks of this emerging technology in relation to standard catheter ablation are discussed.

  16. Measurement of gamma radiation around base station

    International Nuclear Information System (INIS)

    The ? -radiation have been measured around base station in Isparta region of Turkey to see the contribution of base station on the background radiation. Isparta which is surrounded by high mountain of Davras is located at southern part of Turkey. There are several volcanic activity in this region. The background radiation arises from two main sources. These are natural and technological sources. The natural radiation are mainly contributed by cosmic rays and terrestrial radiation. Cosmic rays comes from outside of the atmosphere after supernova explosion in the universe. The radiation comes direct from outside of atmosphere called primer cosmic rays and some of them can create seconder particle such as neutron.proton etc after some reaction with the oxygen, nitrogen etc in the atmosphere. The origin of terrestrial radiation are some radionucleus in rocks and soils. These are mainly 40K, 238U, 232Th and their products. The terrestrial radiation depends on geological structure of the region. The other types of γ-radiation is technological origin. With the development of technology in many different fields radiation can be produced. Nowadays mobile phones are widely used technological device and this requires base station to be established around habitable area. The electromagnetic radiations from base station and its effect are always a big question in people's mind and this would be investigated. The measurement have been performed using ASP/2e counter connected to a sing NaI(Tl) γ-ray detector. It was done around five different base station and also different altitude in Davraz mountain. The radiation dose from ambient air over five months ranges from 50 to 140 nGy h-1. The contribution of base station to the natural background radiation was clearly seen in the measurement

  17. Radiation safety of mobile phones and base stations

    International Nuclear Information System (INIS)

    The recent expansion of personal telecommunications has led to a rapid increase in the exposure of people to the radio-frequency (RF) radiation. Although the mobile phones are low power devices, the antenna is so close to the head that the local exposure may slightly exceed 2 W/kg, the current exposure limit for the local specific absorption rate SAR for the general public. The increase in the temperature is, however, too small to have any physiological significance. On the basis of experiments with cell cultures it is possible that other biological effects caused by some unknown non-thermal mechanism exist, but thus far there is conclusive biological or epidemiological evidence to suggest any diseases adverse physiological changes below the thermal threshold. The use of a mobile phone by a person wearing a pace-maker, the immunity which against the electromagnetic interference from the mobile phone has not be assured, is not recommended. The exposure caused by the base stations is in almost all practical ceases all below the power density limits for general public. (orig.) (115 refs.)

  18. Radiation safety of handheld mobile phones and base stations

    Energy Technology Data Exchange (ETDEWEB)

    Jokela, K.; Leszczynski, D.; Paile, W.; Salomaa, S.; Puranen, L.; Hyysalo, P

    1999-01-01

    The recent expansion of personal telecommunications has led to a rapid increase in the exposure of people to the radio-frequency (RF) radiation. Although the mobile phones are low power devices, the antenna is so close to the head that the local exposure may slightly exceed 2 W/kg, the current exposure limit for the local specific absorption rate SAR for the general public. The increase in the temperature is, however, too small to have any physiological significance. On the basis of experiments with cell cultures it is possible that other biological effects caused by some unknown non-thermal mechanism exist, but thus far there is no conclusive biological or epidemiological evidence to suggest any diseases or adverse physiological changes below the thermal threshold. The use of a mobile phone by a person wearing a pace-maker, is not recommended, if the immunity of the pace-maker has not been assured. The exposure caused by the base stations is in all practical cases well below the power density limits for general public. (author) 118 refs.

  19. Radiation safety of handheld mobile phones and base stations

    International Nuclear Information System (INIS)

    The recent expansion of personal telecommunications has led to a rapid increase in the exposure of people to the radio-frequency (RF) radiation. Although the mobile phones are low power devices, the antenna is so close to the head that the local exposure may slightly exceed 2 W/kg, the current exposure limit for the local specific absorption rate SAR for the general public. The increase in the temperature is, however, too small to have any physiological significance. On the basis of experiments with cell cultures it is possible that other biological effects caused by some unknown non-thermal mechanism exist, but thus far there is no conclusive biological or epidemiological evidence to suggest any diseases or adverse physiological changes below the thermal threshold. The use of a mobile phone by a person wearing a pace-maker, is not recommended, if the immunity of the pace-maker has not been assured. The exposure caused by the base stations is in all practical cases well below the power density limits for general public. (author)

  20. A large-scale measurement of electromagnetic fields near GSM base stations in Guangxi, China for risk communication

    International Nuclear Information System (INIS)

    Radiofrequency (RF) electromagnetic field (EMF) exposure from wireless telecommunication base station antennae can lead to debates, conflicts or litigations among the adjacent residents if inappropriately managed. This paper presents a measurement campaign for the GSM band EMF exposure in the vicinity of 827 base station sites (totally 6207 measurement points) in Guangxi, China. Measurement specifications are designed for risk communication with the residents who previously complained of over-exposure. The EMF power densities with the global positioning system coordinate at each measured point were recorded. Compliance with the International Commission on Non-Ionizing Radiation Protection guidelines and Chinese environmental EMF safety standards was studied. The results show that the GSM band EMF level near the base stations is very low. The measurement results and the EMF risk communication procedures positively influence public perception of the RF EMF exposure from the base stations and promote the exchange of EMF exposure-related knowledge. (authors)

  1. Review of low-noise radio-frequency amplifiers based on superconducting quantum interference device

    International Nuclear Information System (INIS)

    Superconducting quantum interference device (SQUID) is a sensitive detector of magnetic flux signals. Up to now, the main application of SQUIDs has been measurements of magnetic flux signals in the frequency range from near DC to several MHz. Recently, cryogenic low-noise radio-frequency (RF) amplifiers based on DC SQUID are under development aiming to detect RF signals with sensitivity approaching quantum limit. In this paper, we review the recent progress of cryogenic low-noise RF amplifiers based on SQUID technology.

  2. Cooperative Proxy Caching for Wireless Base Stations

    Directory of Open Access Journals (Sweden)

    James Z. Wang

    2007-01-01

    Full Text Available This paper proposes a mobile cache model to facilitate the cooperative proxy caching in wireless base stations. This mobile cache model uses a network cache line to record the caching state information about a web document for effective data search and cache space management. Based on the proposed mobile cache model, a P2P cooperative proxy caching scheme is proposed to use a self-configured and self-managed virtual proxy graph (VPG, independent of the underlying wireless network structure and adaptive to the network and geographic environment changes, to achieve efficient data search, data cache and date replication. Based on demand, the aggregate effect of data caching, searching and replicating actions by individual proxy servers automatically migrates the cached web documents closer to the interested clients. In addition, a cache line migration (CLM strategy is proposed to flow and replicate the heads of network cache lines of web documents associated with a moving mobile host to the new base station during the mobile host handoff. These replicated cache line heads provide direct links to the cached web documents accessed by the moving mobile hosts in the previous base station, thus improving the mobile web caching performance. Performance studies have shown that the proposed P2P cooperative proxy caching schemes significantly outperform existing caching schemes.

  3. Antenna unit and radio base station therewith

    Science.gov (United States)

    Kuwahara, Mikio; Doi, Nobukazu; Suzuki, Toshiro; Ishida, Yuji; Inoue, Takashi; Niida, Sumaru

    2007-04-10

    Phase and amplitude deviations, which are generated, for example, by cables connecting an array antenna of a CDMA base station and the base station, are calibrated in the baseband. The base station comprises: an antenna apparatus 1; couplers 2; an RF unit 3 that converts a receive signal to a baseband signal, converts a transmit signal to a radio frequency, and performs power control; an A/D converter 4 for converting a receive signal to a digital signal; a receive beam form unit 6 that multiplies the receive signal by semi-fixed weight; a despreader 7 for this signal input; a time-space demodulator 8 for demodulating user data; a despreader 9 for probe signal; a space modulator 14 for user data; a spreader 13 for user signal; a channel combiner 12; a Tx calibrater 11 for controlling calibration of a signal; a D/A converter 10; a unit 16 for calculation of correlation matrix for generating a probe signal used for controlling an Rx calibration system and a TX calibration system; a spreader 17 for probe signal; a power control unit 18; a D/A converter 19; an RF unit 20 for probe signal; an A/D converter 21 for signal from the couplers 2; and a despreader 22.

  4. Catheter based radiofrequency ablation of renal nerves for the treatment of resistant hypertension

    Directory of Open Access Journals (Sweden)

    Markus P. Schlaich

    2013-03-01

    Full Text Available Introduction Resistant hypertension is a common and growing clinical problem characterized by the failure to attain target blood pressure levels despite adequate use of at least three antihypertensive agents. Objectives The aim of this article is to emphasize the role of novel approaches to treat resistant hypertension. Materials and methods After an excursus on the physiological role of renal nerves on kidney function, volume homeostasis and blood pressure control, this article describes the radiofrequency ablation technology to obtain kidneys denervation. Results Activation of the sympathetic nervous system plays a prominent role as a major regulator of circulatory and metabolic control. The kidneys have a particularly dense afferent sensory and efferent sympathetic innervation and are thereby strategically positioned to be origin as well as target of sympathetic activation. In this context, recent evidence suggests that a novel catheter-based approach to functionally denervate the human kidneys using radiofrequency ablation technology may provide a safe and effective treatment alternative for resistant hypertension and its adverse consequences. Conclusions Despite the availability of numerous safe and effective pharmacological therapies to treat elevated blood pressure, novel therapeutic approaches are warranted to improve the management and prognosis of patients with refractory hypertension. Several clinical trials are currently conducted and planned to further substantiate the blood pressure lowering efficacy of this novel renal denervation procedure.

  5. Automation for a base station stability testing

    OpenAIRE

    Punnek, Elvis

    2016-01-01

    This Batchelor’s thesis was commissioned by Oy LM Ericsson Ab Oulu. The aim of it was to help to investigate and create a test automation solution for the stability testing of the LTE base station. The main objective was to create a test automation for a predefined test set. This test automation solution had to be created for specific environments and equipment. This work included creating the automation for the test cases and putting them to daily test automation jobs. The key factor...

  6. Radio-frequency discharges in oxygen: I. Particle-based modelling

    International Nuclear Information System (INIS)

    In this series of three papers we present results from a combined experimental and theoretical, particle-based study to quantitatively describe capacitively coupled radio-frequency discharges in oxygen. The particle-in-cell Monte Carlo model on which the theoretical description is based is described in this paper. It treats space charge fields and transport processes on an equal footing with the most important plasma-chemical reactions. For given external voltage and pressure, the model determines the electric potential within the discharge and the distribution functions for electrons, negatively charged atomic oxygen and positively charged molecular oxygen. Previously used scattering and reaction cross section data are critically assessed and in some cases modified. To validate our model, we compare the densities in the bulk of the discharge with experimental data and find good agreement, indicating that essential aspects of an oxygen discharge are captured

  7. GPP-Based Soft Base Station Designing and Optimization

    Institute of Scientific and Technical Information of China (English)

    Xiao-Feng Tao; Yan-Zhao Hou; Kai-Dong Wang; Hai-Yang He; Y.Jay Guo

    2013-01-01

    It is generally acknowledged that mobile communication base stations are composed of hardware components such as Field Programming Gate Array (FPGA),Digital Signal Processor (DSP),which promise reliable and fluent services for the mobile users.However,with the increasing demand for energy-efficiency,approaches of low power-consumption and high-flexibility are needed urgently.In this circumstance,General Purpose Processor (GPP) attracts people's attention for its low-cost and flexibility.Benefited from the development of modern GPP in multi-core,Single Instruction Multiple Data (SIMD) instructions,larger cache,etc.,GPPs are capable of performing high-density digital processing.In this paper,we compare several software-defined radio (SDR) prototypes and propose the general architecture of GPP-based soft base stations.Then,the schematic design of resource allocation and algorithm optimization in soft base station implementation are studied.As an application example,a prototype of GPP-based soft base station referring to the 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is realized and evaluated.To the best of our knowledge,it is the first Soft-LTE prototype ever reported.In the end,we evaluate the timing performance of the LTE soft base station and a packet loss ratio of less than 0.003 is obtained.

  8. Automatic DGD and GVD compensation at 640 Gb/s based on scalar radio-frequency spectrum measurement

    DEFF Research Database (Denmark)

    Paquot, Yvan; Schröder, Jochen; Palushani, Evarist; Neo, Richard; Oxenløwe, Leif Katsuo; Madden, Steve; Choi, Duk-Yong; Luther-Davies, Barry; Pelusi, Mark D.; Eggleton, Benjamin J.

    2013-01-01

    separate GVD and DGD compensators using an impairment monitor based on an integrated all-optical radio-frequency (RF) spectrum analyzer. We show that low-bandwidth measurement of only a single tone in the RF spectrum is sufficient for automatic compensation for multiple degrees of freedom using a...

  9. Remote Impedance-based Loose Bolt Inspection Using a Radio-Frequency Active Sensing Node

    International Nuclear Information System (INIS)

    This paper introduces an active sensing node using radio-frequency (RF) telemetry. This device has brought the traditional impedance-based structural health monitoring (SHM) technique to a new paradigm. The RF active sensing node consists of a miniaturized impedance measuring device (AD5933), a microcontroller (ATmega128L), and a radio frequency (RF) transmitter (XBee). A macro-fiber composite (MFC) patch interrogates a host structure by using a self-sensing technique of the miniaturized impedance measuring device. All the process including structural interrogation, data acquisition, signal processing, and damage diagnostic is being performed at the sensor location by the microcontroller. The RF transmitter is used to communicate the current status of the host structure. The feasibility of the proposed SHM strategy is verified through an experimental study inspecting loose bolts in a bolt-jointed aluminum structure

  10. NASA space station automation: AI-based technology review

    Science.gov (United States)

    Firschein, O.; Georgeff, M. P.; Park, W.; Neumann, P.; Kautz, W. H.; Levitt, K. N.; Rom, R. J.; Poggio, A. A.

    1985-01-01

    Research and Development projects in automation for the Space Station are discussed. Artificial Intelligence (AI) based automation technologies are planned to enhance crew safety through reduced need for EVA, increase crew productivity through the reduction of routine operations, increase space station autonomy, and augment space station capability through the use of teleoperation and robotics. AI technology will also be developed for the servicing of satellites at the Space Station, system monitoring and diagnosis, space manufacturing, and the assembly of large space structures.

  11. Long-Term Efficacy of Radiofrequency Treatment of Turbinate Hypertrophy: A Patient Based Point of View

    OpenAIRE

    Incandela, Cinzia; Calamusa, Giuseppe; Massenti, Maria Fatima; Incandela, Salvatore; Speciale, Riccardo; Amodio, Emanuele

    2011-01-01

    Nasal turbinate hypertrophy is a major cause of nasal airway obstruction that affects up to 20% of the European general population. This study aims to determine the efficacy of radiofrequency treatment as perceived by patients during a 2-years period. From 2007 to 2009, an observational study was conducted on 36 patients who consecutively underwent temperature-controlled radiofrequency tissue volume reduction. A questionnaire was administered to each patient in order to collect demographic da...

  12. Assessment of RF radiation levels in the vicinity of 60 GSM mobile phone base stations in Iran

    International Nuclear Information System (INIS)

    Increasing development of mobile communication infrastructure while enhancing availability of the technology raises concerns among the public, who see more cell towers erected each day, about possible health effects of electromagnetic radiations. Thereon, a survey of radio-frequency radiation from 60 GSM base stations was carried out in Tehran, Iran at several places mostly located in major medical and educational centres. Measurements were performed at 15 locations near each base station site, i.e. 900 locations in total. Since there are other RF radiation sources such as broadcasting services whose carrier frequencies are <3 GHz, the whole band of 27 MHz to 3 GHz has been assessed for hazardous exposures as well. The results were compared with the relevant guideline of International Commission on Non-Ionising Radiation Protection and that of Iran, confirming radiation exposure levels being satisfactorily below defined limits and non-detrimental. (authors)

  13. Radio-frequency ablation-based studies on VX2rabbit models for HCC treatment.

    Science.gov (United States)

    Bimonte, Sabrina; Leongito, Maddalena; Piccirillo, Mauro; de Angelis, Cristina; Pivonello, Claudia; Granata, Vincenza; Izzo, Francesco

    2016-01-01

    Hepatocellular carcinoma (HCC) is the fifth most frequent cancer worldwide with high morbidity, mortality and increasing incidence. It is of note that the main curative therapies for HCC are hepatic resection and transplantation although the majority of patients at the time of presentation are not eligible for resection or orthotopic liver transplantation (OLT) due to the underlying cirrhosis. Currently, a variety of loco-regional therapies, including radiofrequency ablation (RFA), percutaneous ethanol injection (PEI), microwave coagulation therapy (MCT), transarterial chemoembolization (TACE) and others, have been developed as alternative treatment options for HCC. Among these techniques, RFA is currently the most widely used treatment, due to its several advantages, such as safety and efficacy. To date, the effectiveness of RFA for HCC is reduced by the presence of residual tumor as a consequence of insufficient treatment. In order to ameliorate the effects of RFA on HCC, several in vivo studies, have been performed on its application as single or in combination treatment with drugs or others loco-regional therapies, by using rabbit VX2 liver model. This represents an ideal model of liver cancers and is widely used for imaging and other experimental studies due to the rapid growth of these tumors and their similarity to human hepatocellular carcinoma. In order to elucidate the therapeutic potential of RFA with adjuvant treatments for HCC, we reviewed the latest findings on the RFA-based studies in rabbit VX2 hepatocarcinoma models. PMID:27525037

  14. Reversibly Stretchable, Optically Transparent Radio-Frequency Antennas Based on Wavy Ag Nanowire Networks.

    Science.gov (United States)

    Kim, Byoung Soo; Shin, Keun-Young; Pyo, Jun Beom; Lee, Jonghwi; Son, Jeong Gon; Lee, Sang-Soo; Park, Jong Hyuk

    2016-02-01

    We report a facile approach for producing reversibly stretchable, optically transparent radio-frequency antennas based on wavy Ag nanowire (NW) networks. The wavy configuration of Ag NWs is obtained by floating the NW networks on the surface of water, followed by compression. Stretchable antennas are prepared by transferring the compressed NW networks onto elastomeric substrates. The resulting antennas show excellent performance under mechanical deformation due to the wavy configuration, which allows the release of stress applied to the NWs and an increase in the contact area between NWs. The antennas formed from the wavy NW networks exhibit a smaller return loss and a higher radiation efficiency when strained than the antennas formed from the straight NW networks, as well as an improved stability in cyclic deformation tests. Moreover, the wavy NW antennas require a relatively small quantity of NWs, which leads to low production costs and provides an optical transparency. These results demonstrate the potential of these wavy Ag NW antennas in applications of wireless communications for wearable systems. PMID:26760896

  15. Radiation of Base Stations of Mobile Phone

    International Nuclear Information System (INIS)

    In recent years there has been a rapid expansion of new, technological sources of non-ionizing electromagnetic radiation from mobile phones, microwave ovens, various antennas, transmitters, new ultrasound devices. The category of non-ionizing radiation includes electromagnetic radiation at frequencies below 3 000 000 GHz or at ultrasound frequencies below 500 MHz which in interaction with substances do not generate ions. In view of this trend concerns have been raised about the impact of these new (radiation) sources on human health. An increasing amount of scientific research points to the fact that NIR causes various adverse effects to human health: eyes injuries, irritability, insomnia, temporary changes in the metabolism, hazardous heat stress and even carcinoma. The manufacturers and users of radio wave equipment pay great attention to the influence of the electromagnetic fields on human health. This issue has been taken into serious consideration, which is confirmed by a number of studies carried out either by mobile phone manufacturers or by many independent organizations. The limits of electromagnetic radiation exposure are defined in numerous standards and international rule books, and if these limits are complied with, then, according to present knowledge, there is no risk. Considering the concerns of the employees of Ericsson Nikola Tesla the levels of radiation from various types of base stations on company premises were examined. It was found out that there is no hazard to the health of employees. Still, further research is required and it is initiated both by the users and manufacturers of the mobile telephony equipment. (author)

  16. Safety assessment of RF and microwave radiation emitted by the mobile telephone base station (MTBS) in Malaysia: experience and challenge

    International Nuclear Information System (INIS)

    Non-ionising radiation (NIR) is known to be hazardous if the amount received is excessive. It is a fact that NIR, including extremely low frequency (ELF) electromagnetic fields, radiofrequency (RF) and microwave radiation can be found almost everywhere generated by both natural and man-made source. This is due to increase in demand for telecommunication and wireless technology which is become very important and as part of our lives. However, the widespread of the relevant technology contributed more NIR man-made sources exposure to the human. Due to public concern their potential of causing such health hazard, members of public and companies approached and request NIR Group of Nuclear Malaysia to carry out surveys and safety assessments of radiofrequency and microwave radiation emitted by the mobile telephone base station (MTBS) erected near the residential area or installed on the rooftop of the commercial building. Objective of the survey was to assess the presence of radiofrequency and microwave radiation and to identify radiation level which may lead to significant personnel exposure. Findings of the survey was compared to the standard guidelines issued by Malaysian Communication and Multimedia Commission (MCMC) and International Committee on Non-Ionising Radiation Protection (ICNIRP). This paper highlights the works that had been carried out by NIR Group of Nuclear Malaysia from 1997 to 2007. We will share the experience and challenge in carried out the NIR safety assessment at mobile telephone base station. Results of the assessment work will be used to develop non-ionising radiation database for future reference in Malaysia. (Author)

  17. Percutaneous radiofrequency ablation of lung tumors: evaluation of the literature using evidence-based techniques.

    LENUS (Irish Health Repository)

    Chan, Victoria O

    2012-02-01

    PURPOSE: The aim of this study was to evaluate the literature for articles assessing radiofrequency ablation (RFA) for pulmonary malignancy. MATERIALS AND METHODS: The "bottom-up" approach to evidence-based practice was applied by 2 reviewers to the retrieval and appraisal of original research articles published on pulmonary RFA between 2002 and 2009. Primary lung cancer and pulmonary metastases data were analyzed separately. The relationship between the percentage of local recurrence rate and lesion size, patient age, follow-up duration, and time to local recurrence was assessed using Spearman\\'s rank correlation. Discrete time series were used to evaluate time trends. RESULTS: Secondary evidence yielded 1 review of 26 observational studies. Primary evidence yielded 46 studies that seemed suitable for detailed appraisal. A total of 2905 ablations were performed in 1584 patients. Eight studies evaluated primary lung cancers alone, 11 evaluated pulmonary metastases alone, 25 evaluated both, and 2 did not specify the histology. Results revealed trends toward increasing use of conscious sedation over general anesthesia, increasing use of multitined probes, decreasing size of nodule selection, and use of positron emission tomography\\/computed tomography as the optimal follow-up tool. Mean morbidity was 24.6%. The most prevalent side effects included pneumothorax (28.3%), pleural effusions (14.8%), and pain (14.1%). Procedure-related mortality ranged from 0 to 5.6, with an overall procedure-related mortality rate of 0.21%. There were 282 (12.2%) local recurrences occurring at a mean of 13 months. The mean overall survival rate was 59.4%, and the cancer-specific survival rate was 82.6%. CONCLUSIONS: This evidence-based practice review of pulmonary RFA shows it to be a promising treatment for pulmonary malignancy in carefully selected patient populations. Studies with higher levels of evidence, including case-control, prospective nonrandomized and randomized trials

  18. The Concept of Photonics-Based Virtual Ground Tracking Station

    Science.gov (United States)

    Liu, Y.; Cong, B.; Nie, Y. M.; He, J.; Wang, X. Q.

    2016-02-01

    In this paper, we propose the concept of virtual ground tracking station for space missions. Based on microwave photonics, the virtual tracking station can realize spatial diversity, antenna arraying, dynamic resource allocation and distributed signal processing. Compared with conventional design, the flexibility, efficiency and performance can be significantly improved.

  19. Long-term efficacy of radiofrequency treatment of turbinate hypertrophy: a patient based point of view.

    Science.gov (United States)

    Incandela, Cinzia; Calamusa, Giuseppe; Massenti, Maria Fatima; Incandela, Salvatore; Speciale, Riccardo; Amodio, Emanuele

    2013-08-01

    Nasal turbinate hypertrophy is a major cause of nasal airway obstruction that affects up to 20% of the European general population. This study aims to determine the efficacy of radiofrequency treatment as perceived by patients during a 2-years period. From 2007 to 2009, an observational study was conducted on 36 patients who consecutively underwent temperature-controlled radiofrequency tissue volume reduction. A questionnaire was administered to each patient in order to collect demographic data, lifestyle habits, health status and visual analogue scale (VAS) score of perceived symptoms. Mean VAS scores of nasal obstruction, headache, rhinorrhoea and anosmia after treatment were significantly lower than that at baseline. Urban residence and allergic rhinitis were significantly associated with lower mean improvement (2.9 vs. 5.6; P = 0.04 and 2.3 vs. 5.3; P = 0.01, respectively). A non significant association with scarce nasal obstruction improvement was present in older aged patients, in patients other than students and in active and passive smokers. Our data enrich the general knowledge on radiofrequency treatment of turbinate hypertrophy identifying the rate of long-term efficacy of radiofrequency treatment as perceived by patients and focusing on several risk factors involved in patient prognosis after treatment. PMID:24427651

  20. Radiofrequency electromagnetic fields in the Cookridge area of Leeds

    CERN Document Server

    Fuller, K; Judd, P M; Lowe, A J; Shaw, J

    2002-01-01

    On the 8 and 9 May 2002 representatives of the National Radiological Protection Board (NRPB) performed a radiofrequency electromagnetic field survey in the Cookridge area of Leeds in order to assess exposure to radio signals from transmitters mounted on a water tower/a lattice tower and a radio station tower. Guidelines on limiting exposure to radio signals have been published by NRPB and the International Commission on Non-Ionizing Radiation Protection (ICNIRP). These guidelines are designed to prevent established adverse effects on human health. During this survey, the total exposures due to all radio signals from 30 MHz to 18000 MHz (18 GHz) were measured. This frequency range was chosen as it includes mobile phone base station transmissions, which are at around 900 and 1800 MHz and super high frequency (SHF) transmissions from most of the large microwave dish antennas mounted on the towers. In addition, other major sources of radiofrequency electromagnetic fields in the environment such as broadcast radio...

  1. Applicability of an exposure model for the determination of emissions from mobile phone base stations

    International Nuclear Information System (INIS)

    Applicability of a model to estimate radiofrequency electromagnetic field (RF-EMF) strength in households from mobile phone base stations was evaluated with technical data of mobile phone base stations available from the German Net Agency, and dosimetric measurements, performed in an epidemiological study. Estimated exposure and exposure measured with dosemeters in 1322 participating households were compared. For that purpose, the upper 10. percentiles of both outcomes were defined as the 'higher exposed' groups. To assess the agreement of the defined 'higher' exposed groups, kappa coefficient, sensitivity and specificity were calculated. The present results show only a weak agreement of calculations and measurements (kappa values between -0.03 and 0.28, sensitivity between 7.1 and 34.6). Only in some of the sub-analyses, a higher agreement was found, e.g. when measured instead of interpolated geo-coordinates were used to calculate the distance between households and base stations, which is one important parameter in modelling exposure. During the development of the exposure model, more precise input data were available for its internal validation, which yielded kappa values between 0.41 and 0.68 and sensitivity between 55 and 76 for different types of housing areas. Contrary to this, the calculation of exposure - on the basis of the available imprecise data from the epidemiological study - is associated with a relatively high degree of uncertainty. Thus, the model can only be applied in epidemiological studies, when the uncertainty of the input data is considerably reduced. Otherwise, the use of dosemeters to determine the exposure from RF-EMF in epidemiological studies is recommended. (authors)

  2. Quantum key distribution using card, base station and trusted authority

    Energy Technology Data Exchange (ETDEWEB)

    Nordholt, Jane Elizabeth; Hughes, Richard John; Newell, Raymond Thorson; Peterson, Charles Glen; Rosenberg, Danna; McCabe, Kevin Peter; Tyagi, Kush T; Dallman, Nicholas

    2015-04-07

    Techniques and tools for quantum key distribution ("QKD") between a quantum communication ("QC") card, base station and trusted authority are described herein. In example implementations, a QC card contains a miniaturized QC transmitter and couples with a base station. The base station provides a network connection with the trusted authority and can also provide electric power to the QC card. When coupled to the base station, after authentication by the trusted authority, the QC card acquires keys through QKD with a trusted authority. The keys can be used to set up secure communication, for authentication, for access control, or for other purposes. The QC card can be implemented as part of a smart phone or other mobile computing device, or the QC card can be used as a fillgun for distribution of the keys.

  3. Compact field programmable gate array-based pulse-sequencer and radio-frequency generator for experiments with trapped atoms

    International Nuclear Information System (INIS)

    We present a compact field-programmable gate array (FPGA) based pulse sequencer and radio-frequency (RF) generator suitable for experiments with cold trapped ions and atoms. The unit is capable of outputting a pulse sequence with at least 32 transistor-transistor logic (TTL) channels with a timing resolution of 40 ns and contains a built-in 100 MHz frequency counter for counting electrical pulses from a photo-multiplier tube. There are 16 independent direct-digital-synthesizers RF sources with fast (rise-time of ∼60 ns) amplitude switching and sub-mHz frequency tuning from 0 to 800 MHz

  4. Compact field programmable gate array-based pulse-sequencer and radio-frequency generator for experiments with trapped atoms

    Energy Technology Data Exchange (ETDEWEB)

    Pruttivarasin, Thaned, E-mail: thaned.pruttivarasin@riken.jp [Quantum Metrology Laboratory, RIKEN, Wako-shi, Saitama 351-0198 (Japan); Katori, Hidetoshi [Quantum Metrology Laboratory, RIKEN, Wako-shi, Saitama 351-0198 (Japan); Innovative Space-Time Project, ERATO, JST, Bunkyo-ku, Tokyo 113-8656 (Japan); Department of Applied Physics, Graduate School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2015-11-15

    We present a compact field-programmable gate array (FPGA) based pulse sequencer and radio-frequency (RF) generator suitable for experiments with cold trapped ions and atoms. The unit is capable of outputting a pulse sequence with at least 32 transistor-transistor logic (TTL) channels with a timing resolution of 40 ns and contains a built-in 100 MHz frequency counter for counting electrical pulses from a photo-multiplier tube. There are 16 independent direct-digital-synthesizers RF sources with fast (rise-time of ∼60 ns) amplitude switching and sub-mHz frequency tuning from 0 to 800 MHz.

  5. Design, Construction and Operation of a Low-Power, Autonomous Radio-Frequency Data-Acquisition Station for the TARA Experiment

    OpenAIRE

    Kunwar, S.; Abbasi, R.; C. Allen; Belz, J.; Besson, D.; Byrne, M; Farhang-Boroujeny, B; Gillman, W. H.; Hanlon, W.; Hanson, J.; Myers, I.; Novikov, A.; Prohira, S.; Ratzlaff, K.; REZAZADEH, A.

    2015-01-01

    Employing a 40-kW radio-frequency transmitter just west of Delta, UT, and operating at 54.1 MHz, the TARA (Telescope Array RAdar) experiment seeks radar detection of extensive air showers (EAS) initiated by ultra-high energy cosmic rays (UHECR). For UHECR with energies in excess of $10^{19}$ eV, the Doppler-shifted "chirps" resulting from EAS shower core radar reflections should be observable above background (dominantly galactic) at distances of tens of km from the TARA transmitter. In order...

  6. Spatial SINR Games of Base Station Placement and Mobile Association

    CERN Document Server

    Altman, Eitan; Singh, Chandramani; Sundaresan, Rajesh

    2011-01-01

    We study the question of determining locations of base stations that may belong to the same or to competing service providers. We take into account the impact of these decisions on the behavior of intelligent mobile terminals who can connect to the base station that offers the best utility. The signal to interference and noise ratio is used as the quantity that determines the association. We first study the SINR association-game: we determine the cells corresponding to each base stations, i.e., the locations at which mobile terminals prefer to connect to a given base station than to others. We make some surprising observations: (i) displacing a base station a little in one direction may result in a displacement of the boundary of the corresponding cell to the opposite direction; (ii) A cell corresponding to a BS may be the union of disconnected sub-cells. We then study the hierarchical equilibrium in the combined BS location and mobile association problem: we determine where to locate the BSs so as to maximiz...

  7. Assessment and comparison of total RF-EMF exposure in femto-cell and macrocell base station scenarios

    International Nuclear Information System (INIS)

    The indoor coverage of a mobile service can be drastically improved by deployment of an indoor femto-cell base station (FBS). However, the impact of its proximity on the total exposure of the human body to radio-frequency (RF) electromagnetic fields (EMFs) is unknown. Using a framework designed for the combination of near-field and far-field exposure, the authors assessed and compared the RF-EMF exposure of a mobile-phone (MP) user that is either connected to an FBS or a conventional macrocell base station while in an office environment. It is found that, in average macrocell coverage and MP use-time conditions and for Universal Mobile Telecommunications System technology, the total exposure can be reduced by a factor of 20-40 by using an FBS, mostly due to the significant decrease in the output power of the MP. In general, the framework presented in this study can be used for any exposure scenario, featuring any number of technologies, base stations and/or access points, users and duration. (authors)

  8. Exposure assessment of mobile phone base station radiation in an outdoor environment using sequential surrogate modeling.

    Science.gov (United States)

    Aerts, Sam; Deschrijver, Dirk; Joseph, Wout; Verloock, Leen; Goeminne, Francis; Martens, Luc; Dhaene, Tom

    2013-05-01

    Human exposure to background radiofrequency electromagnetic fields (RF-EMF) has been increasing with the introduction of new technologies. There is a definite need for the quantification of RF-EMF exposure but a robust exposure assessment is not yet possible, mainly due to the lack of a fast and efficient measurement procedure. In this article, a new procedure is proposed for accurately mapping the exposure to base station radiation in an outdoor environment based on surrogate modeling and sequential design, an entirely new approach in the domain of dosimetry for human RF exposure. We tested our procedure in an urban area of about 0.04 km(2) for Global System for Mobile Communications (GSM) technology at 900 MHz (GSM900) using a personal exposimeter. Fifty measurement locations were sufficient to obtain a coarse street exposure map, locating regions of high and low exposure; 70 measurement locations were sufficient to characterize the electric field distribution in the area and build an accurate predictive interpolation model. Hence, accurate GSM900 downlink outdoor exposure maps (for use in, e.g., governmental risk communication and epidemiological studies) are developed by combining the proven efficiency of sequential design with the speed of exposimeter measurements and their ease of handling. PMID:23315952

  9. CPU Load Control of LTE Radio Base Station

    OpenAIRE

    Larsson, Joachim

    2015-01-01

    A radio base station (RBS) may become overloaded if too many mobile devices communicate with it at the same time. This could happen at for instance sport events or in the case of accidents. To prevent CPU overload, the RBS is provided with a controller that adjusts the acceptance rate, the maximum number of connection requests that can be accepted per time interval. The current controller is tuned in real radio base stations and the procedure is both time consuming and expensive. This, combin...

  10. Radiation safety of mobile phones and base stations; Matkapuhelimien ja tukiasemien saeteilyturvallisuus

    Energy Technology Data Exchange (ETDEWEB)

    Jokela, K.; Leszczynski, D.; Paile, W.; Salomaa, S.; Puranen, L.; Hyysalo, P.

    1997-06-01

    The recent expansion of personal telecommunications has led to a rapid increase in the exposure of people to the radio-frequency (RF) radiation. Although the mobile phones are low power devices, the antenna is so close to the head that the local exposure may slightly exceed 2 W/kg, the current exposure limit for the local specific absorption rate SAR for the general public. The increase in the temperature is, however, too small to have any physiological significance. On the basis of experiments with cell cultures it is possible that other biological effects caused by some unknown non-thermal mechanism exist, but thus far there is conclusive biological or epidemiological evidence to suggest any diseases adverse physiological changes below the thermal threshold. The use of a mobile phone by a person wearing a pace-maker, the immunity which against the electromagnetic interference from the mobile phone has not be assured, is not recommended. The exposure caused by the base stations is in almost all practical ceases all below the power density limits for general public. (orig.) (115 refs.).

  11. GSM Base Stations Location Monitoring using Geographic Information System

    Directory of Open Access Journals (Sweden)

    Kuboye B. M.

    2013-06-01

    Full Text Available Global System for Mobile Communication (GSM is a digital system developed to meet the desires of the entire public. As the population of a particular area, city or country increases, the number of mobile subscribers increases too. GSM network operators have to reduce congestion on their networks in order to satisfy their subscribers, therefore, a means of monitoring the base stations' locations and the geographical area of where they are located are important factor to achieve this purpose. This work provides a simple step-by-step approach on how to monitor the location of the base stations. A review of GSM and Global Positioning System (GPS technology and their applications to the Geographic Information System (GIS are presented. The means of taken the coordinates of base stations using a GPS device is also presented. ESRI's ArcView application software was used to design the map that shows the location of the base station and thereafter was integrated into the web. It concluded with the recommendation to GSM operators in Nigeria. If the recommendations are given necessary attention, the planning and optimization of cell sites will be enhanced and thereby reduce congestion on network. As a result, the performance of Network will improve, and it will give rise to subscribers' satisfaction and increasing profit returns to the operators.

  12. Exposure to radio waves near mobile phone base stations

    International Nuclear Information System (INIS)

    Measurements of power density have been made at 17 sites where people were concerned about their exposure to radio waves from mobile phone base stations and where technical data, including the frequencies and radiated powers, have been obtained from the operators. Based on the technical data, the radiated power from antennas used with macrocellular base stations in the UK appears to range from a few watts to a few tens of watts, with typical maximum powers around 80 W. Calculations based on this power indicate that compliance distances would be expected to be no more than 3.1 m for the NRPB guidelines and no more than 8.4 m for the ICNIRP public guidelines. Microcellular base stations appear to use powers no more than a few watts and would not be expected to require compliance distances in excess of a few tens of centimetres. Power density from the base stations of interest was measured at 118 locations at the 17 sites and these data were compared with calculations assuming an inverse square law dependence of power density upon distance from the antennas. It was found that the calculations overestimated the measured power density by up to four orders of magnitude at locations that were either not exposed to the main beam from antennas, or shielded by building fabric. For all locations and for distances up to 250 m from the base stations, power density at the measurement positions did not show any trend to decrease with increasing distance. The signals from other sources were frequently found to be of similar strength to the signals from the base stations of interest. Spectral measurements were obtained over the 30 MHz to 2.9 GHz range at 73 of the locations so that total exposure to radio signals could be assessed. The geometric mean total exposure arising from all radio signals at the locations considered was 2 millionths of the NRPB investigation level, or 18 millionths of the lower ICNIRP public reference level; however, the data varied over several decades. The

  13. Population exposure to electromagnetic fields generated by radio base stations: evaluation of the urban background by using provisional model and instrumental measurements

    International Nuclear Information System (INIS)

    Electromagnetic radiation, which is used by broadcasting and mobile telephone systems to transmit information, permeates the city environment. In order to properly evaluate population exposure to electromagnetic fields, knowledge of their intensity and spectral components is necessary. In this study the results of radiofrequency field monitoring carried out in Torino, a large town located in the north-west of Italy are shown: the variation of the electromagnetic field strength is evaluated as a function of the height from the ground, the location in the urban area and the frequency, separating the contributions of the different sources (broadcasting antennas and radio base stations for mobile phones). Furthermore, the contribution of the radio base stations is theoretically evaluated, adding the emissions off all installations situated in Torino and examining the field strength maps calculated, considering the orography, for different heights. The theoretical values are also compared with those measured in the frequency range of mobile telephony emissions. (author)

  14. WORKSHOPS: Radiofrequency superconductivity

    International Nuclear Information System (INIS)

    In the continual push towards higher energy particle beams, superconducting radiofrequency techniques now play a vital role, highlighted in the fifth workshop on radiofrequency superconductivity, held at DESY from 19 - 24 August 1991

  15. Cellular Phone Base Stations: Technology and Exposures (invited paper)

    International Nuclear Information System (INIS)

    The principles and practice of cellular radio systems for mobile communications are presented using GSM 1800 as a reference system. In particular, the concepts of small cells and frequency re-use and the components of radio base station technology are described. Public and cellular broadcasting have been widely available for many years and a brief history is given to indicate length of exposure from these sources. National and international guidelines for safe exposure to non-ionising radiation are used by cellular operators to define exclusion zones around transmitting antennas. A methodology for calculating an exclusion zone is described, together with an example for a typical antenna configuration. Estimated levels of exposure near practical base stations are given and comparisons made with other sources of RF radiation. Finally, the digital nature of today's cellular radio systems, such as GSM, are explained and the implications described. (author)

  16. Impact of Base Station Cooperation on Cell Planning

    Directory of Open Access Journals (Sweden)

    Ian Dexter Garcia

    2010-01-01

    Full Text Available Base station cooperation (BSC has been identified as a key radio access technology for next-generation cellular networks such as LTE-Advanced. BSC impacts cell planning, which is the methodical selection of base station (BS sites, and BS equipment configuration for cost-effective cellular networks. In this paper, the impact of BSC on cell plan parameters (coverage, traffic, handover, and cost, as well as additional cell planning steps required for BSC are discussed. Results show that BSC maximizes its gains over noncooperation (NC in a network wherein interference from cooperating BSs is the main limitation. Locations exist where NC may produce higher throughputs, therefore dynamic or semistatic switching between BSC and NC, called fractional BSC, is recommended. Because of interference from noncooperating BSs, the gains of BSC over NC are upper bounded, and diminishes at greater intersite distances because of noise. This encourages smaller cell sizes, higher transmit powers, and dynamic clustering of cooperative BSs.

  17. Integrating Base Stations with a Software Defined Core Network

    OpenAIRE

    Hernandez Zamora, Bruno

    2016-01-01

    An unprecedented increase is expected in the demand for mobile data traffic, which requires significant changes in the access network. On the one hand, the penetration of new technologies and networks such as Internet of Things (IoT) introduces a large amount of additional traffic of different kinds. On the other hand, the cell size will be reduced, which results in a higher number of base stations that need to be deployed, requiring additional investments by operators. This thesis propos...

  18. On the Statistical Multiplexing Gain of Virtual Base Station Pools

    OpenAIRE

    Liu, Jingchu; Zhou, Sheng; Gong, Jie; Niu, Zhisheng; Xu, Shugong

    2014-01-01

    Facing the explosion of mobile data traffic, cloud radio access network (C-RAN) is proposed recently to overcome the efficiency and flexibility problems with the traditional RAN architecture by centralizing baseband processing. However, there lacks a mathematical model to analyze the statistical multiplexing gain from the pooling of virtual base stations (VBSs) so that the expenditure on fronthaul networks can be justified. In this paper, we address this problem by capturing the session-level...

  19. Measurements of Electromagnetic Fields Emitted from Cellular Base Stations in

    Directory of Open Access Journals (Sweden)

    K. J. Ali

    2013-05-01

    Full Text Available With increasing the usage of mobile communication devices and internet network information, the entry of private telecommunications companies in Iraq has been started since 2003. These companies began to build up cellular towers to accomplish the telecommunication works but they ignore the safety conditions imposed for the health and environment that are considered in random way. These negative health effects which may cause a health risk for life beings and environment pollution. The aim of this work is to determine the safe and unsafe ranges and discuss damage caused by radiation emitted from Asia cell base stations in Shirqat city and discuses the best ways in which can be minimize its exposure level to avoid its negative health effects. Practical measurements of power density around base stations has been accomplished by using a radiation survey meter type (Radio frequency EMF Strength Meter 480846 in two ways. The first way of measurements has been accomplished at a height of 2 meters above ground for different distances from (0-300 meters .The second way is at a distance of 150 meters for different levels from (2-15 meters above ground level. The maximum measured power density is about (3 mW/m2. Results indicate that the levels of power density are far below the RF radiation exposure of USSR safety standards levels. And that means these cellular base station don't cause negative the health effect for life being if the exposure is within the acceptable international standard levels.

  20. Evidence for electron-based ion generation in radio-frequency ionization.

    Science.gov (United States)

    Olaitan, Abayomi D; Zekavat, Behrooz; Solouki, Touradj

    2016-01-01

    Radio-frequency ionization (RFI) is a novel ionization method coupled to mass spectrometry (MS) for analysis of semi-volatile and volatile organic compounds (VOCs). Despite the demonstrated capabilities of RFI MS for VOC analysis in both positive- and negative-ion modes, mechanism of RFI is not completely understood. Improved understanding of the ion generation process in RFI should expand its utility in MS. Here, we studied the possibility of electron emission in RFI using both direct charged particle current measurements and indirect electron detection in a 9.4-T Fourier transform-ion cyclotron resonance (FT-ICR) mass spectrometer. We show that RF-generated electrons can be trapped in the ICR cell and, subsequently, reacted with neutral hexafluorobenzene (C6 F6 ) molecules to generate C6 F6 (●-) . Intensity of observed C6 F6 (●-) species correlated with the number of trapped electrons and decreased as a function of electron quenching period. We also measured the electron attachment rate constant of hexafluorobenzene using a post-RF electron trapping experiment. Measured electron attachment rate constant of hexafluorobenzene (1.19 (±0.53) × 10(-9)  cm(3)  molecule(-1)  s(-1) ) for post-RF FT-ICR MS agreed with the previously reported value (1.60 (±0.30) × 10(-9)  cm(3)  molecule(-1)  s(-1) ) from low-pressure ICR MS measurements. Experimental results from direct and indirect electron measurements suggest that RFI process involves RF-generated electrons under ultrahigh vacuum conditions. PMID:26757067

  1. Risk-based ranking of IST components at Seabrook Station

    International Nuclear Information System (INIS)

    Utilities that operate nuclear power plants are facing increasing cost-competitive pressures. In an effort to maintain, and in most cases improve, safety margins while reducing budgets, many companies are using probabilistic methods to help allocate resources efficiently. Probabilistic ranking methods and strategies are also receiving increasing acceptance from the U.S. Nuclear Regulatory Commission, The American Society of Mechanical Engineers, and other regulatory, standards, and oversight bodies. Application of probabilistic methods at Seabrook Station indicates that inservice testing (IST) has the potential for significant reductions in resource expenditures without compromising safety margins. This paper describes the preliminary results of a risk-based ranking of IST components at Seabrook Station and offers an overview of the strategy for applying these results to the IST program. The application will include additional ranking and sensitivity evaluations (beyond those described in this paper) to ensure the fidelity of the final conclusion

  2. Optimising base station location for UMTS cellular networks

    International Nuclear Information System (INIS)

    Rapid development of universal mobile telecommunication systems put demands on tools for assisting planning of cellular network infrastructure. The tools need to focus on critical issues in modern cellular networks and techniques used for previous generation system no longer serve useful. In this paper, an algorithm based on Branch and Bound approach is proposed for solving base station location problem, covering interference levels, traffic demands and power control mechanism. The efficiency of the algorithm is evaluated with respect to existing approaches for solving this problem – using the designed and implemented experimentation system

  3. Reproducibility of volumetric intravascular ultrasound radiofrequency-based analysis of coronary plaque composition in vivo.

    Science.gov (United States)

    Hartmann, Marc; Mattern, Eline S K; Huisman, Jennifer; van Houwelingen, Gert K; de Man, Frits H A F; Stoel, Martin G; Danse, Peter W; Louwerenburg, Hans W; von Birgelen, Clemens

    2009-01-01

    Intravascular ultrasound radiofrequency (RF-IVUS) data permit the analysis of coronary plaque composition in vivo and is used as an endpoint of ongoing pharmacological intervention trials. We assessed the reproducibility of volumetric RF-IVUS analyses in mild-to-moderately diseased atherosclerotic human coronary arteries in vivo. A total of 9,212 IVUS analyses on cross-sectional IVUS frames was performed to evaluate the reproducibility of volumetric RF-IVUS measurements in 33 coronary segments with a length of 27 +/- 7 mm. For vessel, lumen, and plaque + media volume the relative measurement differences (P = NS for all) were (A = intraobserver comparison, same pullback) -0.40 +/- 1.0%; -0.48 +/- 1.4%; -0.35 +/- 1.6%, (B = intraobserver comparison, repeated pullback) -0.42 +/- 1.2%; -0.52 +/- 1.8%; -0.43 +/- 4.5% (C = interobserver comparison, same pullback) 0.71 +/- 1.8%; 0.71 +/- 2.2%, and 0.89 +/- 5.0%, respectively. For fibrous, fibro-lipidic, calcium, and necrotic-core volumes the relative measurement differences (P = NS for all) were (A) 0.45 +/- 2.1%; -1.12 +/- 4.9%; -0.84 +/- 2.1%; -0.22 +/- 1.8%, (B) 1.40 +/- 4.1%; 1.26 +/- 6.7%; 2.66 +/- 7.4%; 0.85 +/- 4.4%, and (C) -1.60 +/- 4.9%; 3.85 +/- 8.2%; 1.66 +/- 7.5%, and -1.58 +/- 4.7%, respectively. Of note, necrotic-core volume showed on average the lowest measurement variability. Thus, in mild-to-moderate atherosclerotic coronary artery disease the reproducibility of volumetric compositional RF-IVUS measurements from the same pullback is relatively high, but lower than the reproducibility of geometrical IVUS measurements. Measurements from repeated pullbacks and by different observers show acceptable reproducibilities; the volumetric measurement of the necrotic-core shows on average the highest reproducibility of the compositional RF-IVUS measurements. PMID:18704753

  4. Optimization of Base Station and Maximizing the Lifetime of Wireless Sensor Network

    OpenAIRE

    P. Parthiban; G.Sundararaj; K.A.Jagadheesh; P.Maniiarasan

    2014-01-01

    Maximizing the Wireless Sensor Networks (WSNs) lifetime is one of the most remarkable studies in the academic and the industrial research. In the existing Base station locations, the sensor network lifetime is short due to higher energy consumption. Higher energy consumption is due to the non-optimized location of base station. Non optimized location increases the distance between the sensor nodes to the base station, so it will not transfer the data directly to the base station. Each node tr...

  5. Application of microprocessor based technology in CANDU Stations

    International Nuclear Information System (INIS)

    In early 80s, absence of more efficient, cost effective, reliable control hardware was experienced by the nuclear industry. Usage of microprocessor based technology was not prevalent in the nuclear industry due to lack of experience and infancy of the new technology at that time. In 1985, microprocessor based technology, 'Chameleon micro DCI Controllers' manufactured by Fischer and Porter was the 1st application of such technology in any safety related applications in a CANDU Station. The application was for In-Core LOCA logic in Emergency Coolant Injection System (ECIS) modification in Pickering A Nuclear Station. This was followed by use of the same hardware for modification of 'Dump-Arrest' logic for shut-down system in Pickering A in 1986. Other applications were 'Heat Transport Pump Trip Logic' in Bruce A in 1989. The hardware performed very well and far exceeded its predicted availability during the last 22 years of operation. In early 90's Power House Emergency Venting system used 22 micro DCI controllers for Pickering A and B Stations. The use of microprocessor based technology helped meeting the timing requirements of initiating Powerhouse Emergency Venting within 3 seconds of a steam break accident in reactor auxiliary bay. Development of digital trip meter was undertaken in 1991 to solve human-factors related issue of interpretation of HT system saturation trip margin as the analog indicator lacked accuracy and resolution. This was a significant milestone in use of digital technology in safety related applications in any CANDU Station. The process offered an opportunity of trial use of software standards developed by OPG and AECL for category 1 safety critical software systems. This application generated significant learning experience for OPG (then Ontario Hydro) and the industry. OPG was ahead of other nuclear utilities in implementation of microprocessor based technology in early 80s and 90s. OPG initiatives generated lot of design, maintenance and

  6. Analysis of Synchronization Impairments for Cooperative Base Stations Using OFDM

    Directory of Open Access Journals (Sweden)

    Konstantinos Manolakis

    2015-01-01

    Full Text Available Base station cooperation is envisioned as a key technology for future cellular networks, as it has the potential to eliminate intercell interference and to enhance spectral efficiency. To date, there is still lack of understanding of how imperfect carrier and sampling frequency synchronization between transmitters and receivers limit the potential gains and what the actual system requirements are. In this paper, OFDM signal model is established for multiuser multicellular networks, describing the joint effect of multiple carrier and sampling frequency offsets. It is shown that the impact of sampling offsets is much smaller than the impact of carrier frequency offsets. The model is extended to the downlink of base-coordinated networks and closed-form expressions are derived for the mean power of users’ self-signal, interuser, and intercarrier interference, whereas it is shown that interuser interference is the main source of degradation. The SIR is inverse to the base stations’ carrier frequency variance and to the square of time since the last precoder update, whereas it grows with the number of base stations and drops with the number of users. Through user selection, the derived SIR upper bound can be approached. Finally, system design recommendations for meeting synchronization requirements are provided.

  7. Compact Microstrip Feeding Network for Mobile Base Station Antenna

    Directory of Open Access Journals (Sweden)

    Mohamed S. El-gendy, Haythem H. Abdullah, Esmat A. Abdallah

    2016-07-01

    Full Text Available Most mobile base station antennas constituted from an array of radiating elements fed by a feeding network circuit that satisfy shaping the radiation pattern to meet the desired specifications. In this paper, a feeding network circuit is designed to feed mobile base station antenna array. The number of antenna array elements that satisfies the desired beamwidth and side lobe level is ten. The base station antenna covers the operating band from 0.2 GHz to 2.57 GHz, so it supports GSM380, GSM410, GSM450, GSM480, GSM 710, GSM750, GSM810, GSM850, GSM900, GSM1800 / DCS1800, GSM1900 / PCS1900, UMTS2100, and some used LTE bands. Two feeding circuits are designed one for lower band that extends from 200 MHz to 960 MHz and the other is used for upper band that extends from 1.71 GHz to 2.17 GHz. A compact dual-band microstrip equal Wilkinson power divider looks like zigzag shape yields a size reduction of 45.68 % than the conventional shape is utilized in the feeding network circuit. Two cascaded stages of unequal Wilkinson power divider (UWPD with certain power division ratios at the out ports are proposed. A three unit hippocampus - shaped defected ground structure (DGS pattern etched on the ground plane and placed underneath one of the microstrip branch line of both cascaded unequal Wilkinson power divider is used to realize 102 Ω lines with a wider width of 1.6 mm. The feeding network is designed and fabricated on FR4 dielectric substrate with dielectric constant of εr = 4.5, loss tangent 0.025 and substrate height of 1.5 mm.

  8. Analysis of low-dimensional radio-frequency impedance-based cardio-synchronous waveforms for biometric authentication.

    Science.gov (United States)

    Venugopalan, Shreyas; Savvides, Marios; Griofa, Marc O; Cohen, Ken

    2014-08-01

    Over the past two decades, there have been a lot of advances in the field of pattern analyses for biomedical signals, which have helped in both medical diagnoses and in furthering our understanding of the human body. A relatively recent area of interest is the utility of biomedical signals in the field of biometrics, i.e., for user identification. Seminal work in this domain has already been done using electrocardiograph (ECG) signals. In this paper, we discuss our ongoing work in using a relatively recent modality of biomedical signals-a cardio-synchronous waveform measured using a Radio-Frequency Impedance-Interrogation (RFII) device for the purpose of user identification. Compared to an ECG setup, this device is noninvasive and measurements can be obtained easily and quickly. Here, we discuss the feasibility of reducing the dimensions of these signals by projecting onto various subspaces while still preserving interuser discriminating information. We compare the classification performance using classical dimensionality reduction methods such as principal component analysis (PCA), independent component analysis (ICA), random projections, with more recent techniques such as K-SVD-based dictionary learning. We also report the reconstruction accuracies in these subspaces. Our results show that the dimensionality of the measured signals can be reduced by 60 fold while maintaining high user identification rates. PMID:23846435

  9. Massive MIMO Systems with Hardware-Constrained Base Stations

    OpenAIRE

    Bjornson, Emil; Matthaiou, Michail; Debbah, Merouane

    2014-01-01

    Massive multiple-input multiple-output (MIMO) systems are cellu-lar networks where the base stations (BSs) are equipped with un-conventionally many antennas. Such large antenna arrays offer huge spatial degrees-of-freedom for transmission optimization; in partic-ular, great signal gains, resilience to imperfect channel knowledge, and small inter-user interference are all achievable without exten-sive inter-cell coordination. The key to cost-efficient deployment of large arrays is the use of h...

  10. Transmit Diversity at the Cell Border Using Smart Base Stations

    Directory of Open Access Journals (Sweden)

    Plass Simon

    2007-01-01

    Full Text Available We address the problems at the most critical area in a cellular multicarrier code division multiple access (MC-CDMA network, namely, the cell border. At a mobile terminal the diversity can be increased by using transmit diversity techniques such as cyclic delay diversity (CDD and space-time coding like Alamouti. We transfer these transmit diversity techniques to a cellular environment. Therefore, the performance is enhanced at the cell border, intercellular interference is avoided, and soft handover procedures are simplified all together. By this, macrodiversity concepts are exchanged by transmit diversity concepts. These concepts also shift parts of the complexity from the mobile terminal to smart base stations.

  11. Securing Localization With Hidden and Mobile Base Stations

    DEFF Research Database (Denmark)

    Capkun, Srdjan; Srivastava, Mani; Cagalj, Mario

    2006-01-01

    Until recently, the problem of localization in wireless networks has been mainly studied in a nonadversarial setting. Only recently, a number of solutions have been proposed that aim to detect and prevent attacks on localization systems. In this work, we propose a new approach to secure...... localization based on hidden and mobile base stations. Our approach enables secure localization with a broad spectrum of localization techniques: ultrasonic or radio, based on received signal strength or signal time of flight. Through several examples we show how this approach can be used to secure nodecentric...... and infrastructure-centric localization schemes. We further show how this approach can be applied to secure localization in sensor networks....

  12. Charging stations location model based on spatiotemporal electromobility use patterns

    Science.gov (United States)

    Pagany, Raphaela; Marquardt, Anna; Zink, Roland

    2016-04-01

    One of the major challenges for mainstream adoption of electric vehicles is the provision of infrastructure for charging the batteries of the vehicles. The charging stations must not only be located dense enough to allow users to complete their journeys, but the electric energy must also be provided from renewable sources in order to truly offer a transportation with less CO2 emissions. The examination of potential locations for the charging of electric vehicles can facilitate the adaption of electromobility and the integration of electronic vehicles in everyday life. A geographic information system (GIS) based model for optimal location of charging stations in a small and regional scale is presented. This considers parameters such as the forecast of electric vehicle use penetration, the relevant weight of diverse point of interests and the distance between parking area and destination for different vehicle users. In addition to the spatial scale the temporal modelling of the energy demand at the different charging locations has to be considerate. Depending on different user profiles (commuters, short haul drivers etc.) the frequency of charging vary during the day, the week and the year. In consequence, the spatiotemporal variability is a challenge for a reliable energy supply inside a decentralized renewable energy system. The presented model delivers on the one side the most adequate identified locations for charging stations and on the other side the interaction between energy supply and demand for electromobility under the consideration of temporal aspects. Using ESRI ArcGIS Desktop, first results for the case study region of Lower Bavaria are generated. The aim of the concept is to keep the model transferable to other regions and also open to integrate further and more detailed user profiles, derived from social studies about i.e. the daily behavior and the perception of electromobility in a next step.

  13. Monitoring and optimization of energy consumption of base transceiver stations

    CERN Document Server

    Spagnuolo, Antonio; Vetromile, Carmela; Formosi, Roberto; Lubritto, Carmine

    2015-01-01

    The growth and development of the mobile phone network has led to an increased demand for energy by the telecommunications sector, with a noticeable impact on the environment. Monitoring of energy consumption is a great tool for understanding how to better manage this consumption and find the best strategy to adopt in order to maximize reduction of unnecessary usage of electricity. This paper reports on a monitoring campaign performed on six Base Transceiver Stations (BSs) located central Italy, with different technology, typology and technical characteristics. The study focuses on monitoring energy consumption and environmental parameters (temperature, noise, and global radiation), linking energy consumption with the load of telephone traffic and with the air conditioning functions used to cool the transmission equipment. Moreover, using experimental data collected, it is shown, with a Monte Carlo simulation based on power saving features, how the BS monitored could save energy.

  14. Cooling water practices at coal and gas based power stations

    International Nuclear Information System (INIS)

    Water is used for a number of diverse purposes in a power plant. In most cases, the water cannot be used as such and requires treatment to ensure higher efficiency and protection of equipment. Corrosion, scale deposition and fouling have since long posed as challenges to the technical expertise of cooling water chemists at industrial and utility power plants. The study of the raw water, water samples from the CW tower basin and clarified water of various coal and gas based power stations has indicated that problem of corrosion and scale formation are linked with the quality of raw water and operating parameters. The present paper deals with the different cooling water treatment practices being followed at various power stations and which have been quite helpful in improving the quality of water and reduce scale promotion, thereby improving heat transfer of condenser and heat exchangers, and in addition to prevent corrosion in the pipelines, water boxes, tube plates and condenser tubes. The above said studies constitutes a part of the Research work being carried out by corrosion group of Research and Development Centre, NTPC under the project entitled evaluation of standards for cooling water treatment which has been sanctioned under CBIP (Central Board of Irrigation and Power) action plan by Department of Power to Research and Development Centre of NTPC in the 8th plan period. (author)

  15. Exposure to electromagnetic radiation from GSM and UMTS base station antennas

    International Nuclear Information System (INIS)

    This paper discusses processes for measurement of GSM and UMTS signal strength on different scenarios, regarding base stations compliance evaluation with radiation exposure limits. Recommendations to minimize exposure from base station antennas' radiation are also established. Propagation models application and their importance to base stations security evaluation are analysed. An application example of the use of these models in a software tool development is given. A measurement campaign to collect real data from base stations in Lisbon is described, and propagation models applicability is discussed. Radiation reference levels were never exceeded on the analysed base stations. The worst-case detected was about five time (in terms of electric field strength) below security limits adopted by the European Union Council. Nevertheless, in general, the measured stations were at least thirteen times below limits. Scenarios where differences between measurements and limits are lower and exposure on buildings' rooftops with base stations and indoors. (author)

  16. Fibrillation number based on wavelength and critical mass in patients who underwent radiofrequency catheter ablation for atrial fibrillation.

    Science.gov (United States)

    Hwang, Minki; Park, Junbeum; Lee, Young-Seon; Park, Jae Hyung; Choi, Sung Hwan; Shim, Eun Bo; Pak, Hui-Nam

    2015-02-01

    The heart characteristic length, the inverse of conduction velocity (CV), and the inverse of the refractory period are known to determine vulnerability to cardiac fibrillation (fibrillation number, FibN) in in silico or ex vivo models. The purpose of this study was to validate the accuracy of FibN through in silico atrial modeling and to evaluate its clinical application in patients with atrial fibrillation (AF) who had undergone radiofrequency catheter ablation. We compared the maintenance duration of AF at various FibNAF values using in silico bidomain atrial modeling. Among 60 patients (72% male, 54±13 years old, 82% with paroxysmal AF) who underwent circumferential pulmonary vein isolation (CPVI) for AF rhythm control, we examined the relationship between FibN AF and postprocedural AF inducibility or induction pacing cycle length (iPCL). Clinical FibNAF was calculated using left atrium (LA) dimension (echocardiogram), the inverse of CV, and the inverse of the atrial effective refractory periods measured at proximal and distal coronary sinus. In silico simulation found a positive correlation between AF maintenance duration and FibNAF ( R = 0.90, ). After clinical CPVI, FibNAF ( 0.296±0.038 versus 0.192±0.028, ) was significantly higher in patients with postprocedural AF inducibility ( n = 41) than in those without ( n = 19 ). Among 41 patients with postprocedural AF inducibility, FibNAF ( P = 0.935, ) had excellent correlations with induction pacing cycle length. FibNAF, based on LA mass and wavelength, correlates well with AF maintenance in computational modeling and clinical AF inducibility after CPVI. PMID:25343755

  17. Station-based Surface Data Value-Added Product

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Q. [DOE ARM Climate Research Facility, Washington, DC (United States); Xie, S. [DOE ARM Climate Research Facility, Washington, DC (United States)

    2015-07-01

    This report describes the Atmospheric Radiation Measurement (ARM) Best Estimate (ARMBE) station-based surface data (ARMBESTNS) value-added product. It is a twin data product of the ARMBE 2-Dimensional gridded (ARMBE2DGRID) data set. Unlike the ARMBE2DGRID data set, ARMBESTNS data are reported at the original site locations and show the original information (except for the interpolation over time). Therefore, the users have the flexibility to process the data with the approach more suitable for their applications. This document provides information about the input data, quality control (QC) method, and output format of this data set. As much of the information is identical to that of the ARMBE2DGRID data, this document will emphasize more on the different aspects of these two data sets.

  18. Greening radio access networks using distributed base station architectures

    DEFF Research Database (Denmark)

    Kardaras, Georgios; Soler, José; Dittmann, Lars

    2010-01-01

    Several actions for developing environmentally friendly technologies have been taken in most industrial fields. Significant resources have also been devoted in mobile communications industry. Moving towards eco-friendly alternatives is primarily a social responsibility for network operators....... However besides this, increasing energy efficiency represents a key factor for reducing operating expenses and deploying cost effective mobile networks. This paper presents how distributed base station architectures can contribute in greening radio access networks. More specifically, the advantages of...... introducing remote radio head modules are discussed. Substantial flexibility is provided in terms of power consumption, as a result of combining efficient hardware with intelligent software. Additionally, it is underlined that designing eco-sustainable systems needs to follow a holistic approach towards...

  19. Coverage and Economy of Cellular Networks with Many Base Stations

    CERN Document Server

    Lee, Seunghyun

    2012-01-01

    The performance of a cellular network can be significantly improved by employing many base stations (BSs), which shortens transmission distances. However, there exist no known results on quantifying the performance gains from deploying many BSs. To address this issue, we adopt a stochastic-geometry model of the downlink cellular network and analyze the mobile outage probability. Specifically, given Poisson distributed BSs, the outage probability is shown to diminish inversely with the increasing ratio between the BS and mobile densities. Furthermore, we analyze the optimal tradeoff between the performance gain from increasing the BS density and the resultant network cost accounting for energy consumption, BS hardware and backhaul cables. The optimal BS density is proved to be proportional to the square root of the mobile density and the inverse of the square root of the cost factors considered.

  20. Radio Coverage inside Tunnel Utilizing Leaky Coaxial Cable Base Station

    Directory of Open Access Journals (Sweden)

    F. Sayadi

    2009-01-01

    Full Text Available In this study, tunnels radio coverage utilizing leaky coaxial cable has been described. This cable can be deployed as a base station antenna for indoor wireless system such as tunnels. The older type of leaky cables is called coupled mode, while latest type is called radiation mode. These two modes can be distinguished by their radiation pattern, method of radiation (i.e., wave or energy and class of slot on outer conductor. To obtain the field radiation patterns, we use two models; diffuse and deterministic models. Then a modified ray tracing algorithm has been used and simulated to predict radio coverage in tunnels by leaky cable deployment. Simulations show that leaky cables achieve better RF coverage than distributed antennas in term of received signal level versus frequency for various lengths and cross section of tunnels.

  1. Railway Station Facilities in Rural and Urban Services Based on Observation and User Feedback

    Directory of Open Access Journals (Sweden)

    Mohd Masirin Mohd Idrus

    2016-01-01

    Full Text Available Public transport is one of the facilities available in Malaysia. Overwhelming demand from the community has demanded public transport as an alternative for some people to do their daily activities. The increasing of Malaysian population brought many problems to the environment especially traffic congestion problem. The Government spends a lot of money to overcome this problem [10]. Public transport has been upgraded to ensure user comfort. Most people in the city are more interested in using railway transport as traffic congestion and travel time accuracy is better than other public transport [1, 5]. To influence public demand, the facilities available at the train station should be complete [3, 5]. The choice of location for the study are Batu Gajah station (station 1 and Kluang station (station 2 for rural services while Bandar Tasik Selatan station (station 3 and KL Central station (station 4 for urban services. The results of this study showed that, based on data and information obtained from field survey work and the feedback questionnaires from users, basic facilities at railway stations surveyed for urban and rural services can be identified and listed. An analysis of the status of the facilities at railway stations can be established through the safety of passengers and observations in the field. The facilities available at the urban service station are more complete than in rural service station. Facilities at railway station should be improved to attract people using the facilities.

  2. NASA space station automation: AI-based technology review. Executive summary

    Science.gov (United States)

    Firschein, O.; Georgeff, M. P.; Park, W.; Cheeseman, P. C.; Goldberg, J.; Neumann, P.; Kautz, W. H.; Levitt, K. N.; Rom, R. J.; Poggio, A. A.

    1985-01-01

    Research and Development projects in automation technology for the Space Station are described. Artificial Intelligence (AI) based technologies are planned to enhance crew safety through reduced need for EVA, increase crew productivity through the reduction of routine operations, increase space station autonomy, and augment space station capability through the use of teleoperation and robotics.

  3. Monitoring and optimization of energy consumption of base transceiver stations

    International Nuclear Information System (INIS)

    The growth and development of the mobile phone network has led to an increased demand for energy by the telecommunications sector, with a noticeable impact on the environment. Monitoring of energy consumption is a great tool for understanding how to better manage this consumption and find the best strategy to adopt in order to maximize reduction of unnecessary usage of electricity. This paper reports on a monitoring campaign performed on six BSs (Base Transceiver Stations) located central Italy, with different technology, typology and technical characteristics. The study focuses on monitoring energy consumption and environmental parameters (temperature, noise, and global radiation), linking energy consumption with the load of telephone traffic and with the air conditioning functions used to cool the transmission equipment. Moreover, using experimental data collected, it is shown, with a Monte Carlo simulation based on power saving features, how the BS monitored could save energy. - Highlights: • Energy consumption and environmental parameters of a base transceiver system have been monitored. • Energy consumption is related to the air conditioning functions and to the load of telephone traffic. • Energy saving can be obtained by careful choice of cooling parameters and by turn off BS transceivers. • Energy saving parameters can be estimated by a simulation Monte Carlo method

  4. Mobile phone base station-emitted radiation does not induce phosphorylation of Hsp27.

    Science.gov (United States)

    Hirose, H; Sakuma, N; Kaji, N; Nakayama, K; Inoue, K; Sekijima, M; Nojima, T; Miyakoshi, J

    2007-02-01

    An in vitro study focusing on the effects of low-level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT-2000) cellular system was conducted to test the hypothesis that modulated RF fields act to induce phosphorylation and overexpression of heat shock protein hsp27. First, we evaluated the responses of human cells to microwave exposure at a specific absorption rate (SAR) of 80 mW/kg, which corresponds to the limit of the average whole-body SAR for general public exposure defined as a basic restriction in the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Second, we investigated whether continuous wave (CW) and Wideband Code Division Multiple Access (W-CDMA) modulated signal RF fields at 2.1425 GHz induced activation or gene expression of hsp27 and other heat shock proteins (hsps). Human glioblastoma A172 cells were exposed to W-CDMA radiation at SARs of 80 and 800 mW/kg for 2-48 h, and CW radiation at 80 mW/kg for 24 h. Human IMR-90 fibroblasts from fetal lungs were exposed to W-CDMA at 80 and 800 mW/kg for 2 or 28 h, and CW at 80 mW/kg for 28 h. Under the RF field exposure conditions described above, no significant differences in the expression levels of phosphorylated hsp27 at serine 82 (hsp27[pS82]) were observed between the test groups exposed to W-CDMA or CW signal and the sham-exposed negative controls, as evaluated immediately after the exposure periods by bead-based multiplex assays. Moreover, no noticeable differences in the gene expression of hsps were observed between the test groups and the negative controls by DNA Chip analysis. Our results confirm that exposure to low-level RF field up to 800 mW/kg does not induce phosphorylation of hsp27 or expression of hsp gene family. PMID:17004241

  5. Discrimination between weaned and unweaned Atlantic cod (Gadus morhua in capture-based aquaculture (CBA by X-ray imaging and radio-frequency metal detector.

    Directory of Open Access Journals (Sweden)

    Ekrem Misimi

    Full Text Available The aim of this study was to investigate the feasibility of two detection methods for use in discrimination and sorting of adult Atlantic cod (about 2 kg in the small scale capture-based aquaculture (CBA. Presently, there is no established method for discrimination of weaned and unweaned cod in CBA. Generally, 60-70% of the wild-caught cod in the CBA are weaned into commercial dry feed. To increase profitability for the fish farmers, unweaned cod must be separated from the stock, meaning the fish must be sorted into two groups - unweaned and weaned from moist feed. The challenges with handling of large numbers of fish in cages, defined the limits of the applied technology. As a result, a working model was established, focusing on implementing different marking materials added to the fish feed, and different technology for detecting the feed presence in the fish gut. X-ray imaging in two modes (planar and dual energy band and sensitive radio-frequency metal detection were the detection methods that were chosen for the investigations. Both methods were tested in laboratory conditions using dead fish with marked feed inserted into the gut cavity. In particular, the sensitive radio-frequency metal detection method with carbonyl powder showed very promising results in detection of marked feed. Results show also that Dual energy band X-ray imaging may have potential for prediction of fat content in the feed. Based on the investigations it can be concluded that both X-ray imaging and sensitive radio-frequency metal detector technology have the potential for detecting cod having consumed marked feed. These are all technologies that may be adapted to large scale handling of fish from fish cages. Thus, it may be possible to discriminate between unweaned and weaned cod in a large scale grading situation. Based on the results of this study, a suggestion for evaluation of concept for in-situ sorting system is presented.

  6. Prospects of Hybrid Plasma- and Radiofrequency-Based Electron Acceleration at DESY

    Science.gov (United States)

    Osterhoff, Jens; Gruener, Florian; Elsen, Eckhard; Floettmann, Klaus; Foster, Brian; Brinkmann, Reinhard; Schmidt, Bernhard; Schlarb, Holger; Stephan, Frank

    2012-10-01

    The field of particle acceleration in plasma wakes has seen remarkable progress in recent years. Accelerating gradients of more than 10 GV/m can now be readily achieved using either ultra-short intense laser pulses or particle beams as wake drivers. The demonstration of the first GeV electron beams and a general trend towards improved reproducibility, beam quality and control over the involved plasma processes has led to plasma-acceleration techniques beginning to draw considerable interest in the traditional accelerator community. As a consequence, DESY, Germany's leading accelerator center, has established a research program for plasma-based novel acceleration techniques with the goal of exploiting the synergetic combination of conventional and new accelerator technology. Such a concept offers an attractive pathway to study many mechanisms occurring in plasma-based accelerators, for example electron-beam-emittance evolution, extreme bunch compression, the controlled emission of betatron radiation, and staging of accelerating units. In addition, it is assumed that bypassing the difficult-to-master process of particle self-injection, which is utilized in all current laser-plasma acceleration schemes, will greatly enhance the reliability of such machines compared to the state-of-the-art.

  7. Wireless Hydrogen Smart Sensor Based on Pt/Graphene-Immobilized Radio-Frequency Identification Tag.

    Science.gov (United States)

    Lee, Jun Seop; Oh, Jungkyun; Jun, Jaemoon; Jang, Jyongsik

    2015-08-25

    Hydrogen, a clean-burning fuel, is of key importance to various industrial applications, including fuel cells and the aerospace and automotive industries. However, hydrogen gas is odorless, colorless, and highly flammable; thus, appropriate safety protocol implementation and monitoring are essential. Highly sensitive hydrogen-gas leak detection and surveillance systems are needed; additionally, the ability to monitor large areas (e.g., cities) via wireless networks is becoming increasingly important. In this report, we introduce a radio frequency identification (RFID)-based wireless smart-sensor system, composed of a Pt-decorated reduced graphene oxide (Pt_rGO)-immobilized RFID sensor tag and an RFID-reader antenna-connected network analyzer to detect hydrogen gas. The Pt_rGOs, produced using a simple chemical reduction process, were immobilized on an antenna pattern in the sensor tag through spin coating. The resulting Pt_rGO-based RFID sensor tag exhibited a high sensitivity to hydrogen gas at unprecedentedly low concentrations (1 ppm), with wireless communication between the sensor tag and RFID-reader antenna. The wireless sensor tag demonstrated flexibility and a long lifetime due to the strong immobilization of Pt_rGOs on the substrate and battery-independent operation during hydrogen sensing, respectively. PMID:26060881

  8. Measurements and Modelling of Base Station Power Consumption under Real Traffic Loads

    Directory of Open Access Journals (Sweden)

    Goran Petrovic

    2012-03-01

    Full Text Available Base stations represent the main contributor to the energy consumption of a mobile cellular network. Since traffic load in mobile networks significantly varies during a working or weekend day, it is important to quantify the influence of these variations on the base station power consumption. Therefore, this paper investigates changes in the instantaneous power consumption of GSM (Global System for Mobile Communications and UMTS (Universal Mobile Telecommunications System base stations according to their respective traffic load. The real data in terms of the power consumption and traffic load have been obtained from continuous measurements performed on a fully operated base station site. Measurements show the existence of a direct relationship between base station traffic load and power consumption. According to this relationship, we develop a linear power consumption model for base stations of both technologies. This paper also gives an overview of the most important concepts which are being proposed to make cellular networks more energy-efficient.

  9. Multi-band radio-frequency filters fabricated using polyimide-based membrane transfer bonding technology

    International Nuclear Information System (INIS)

    In this paper, we present a polyimide-based Si membrane transfer bonding technology and its application to CMOS-compatible integration of different modes of AlN/Si composite piezoelectric MEMS resonators. The thermosetting polyimide, which has excellent chemical resistance and thermal stability, is used as a bonding adhesion, and is successfully removed as a sacrificial layer by O2 plasma to release free-standing MEMS devices. The whole process temperature is below 350 °C and compatible with CMOS LSI. Using this technology, different modes of AlN/Si resonators, which are film bulk acoustic wave resonators and wine-glass mode disk-type resonators, have been co-fabricated on the same wafer. We also fabricated a ladder-type FBAR filter with a center frequency of 7.71 GHz and a mechanically coupled disk-array filter with a center frequency of 292.8 GHz.

  10. Deep Space Habitat Configurations Based on International Space Station Systems

    Science.gov (United States)

    Smitherman, David; Russell, Tiffany; Baysinger, Mike; Capizzo, Pete; Fabisinski, Leo; Griffin, Brand; Hornsby, Linda; Maples, Dauphne; Miernik, Janie

    2012-01-01

    A Deep Space Habitat (DSH) is the crew habitation module designed for long duration missions. Although humans have lived in space for many years, there has never been a habitat beyond low-Earth-orbit. As part of the Advanced Exploration Systems (AES) Habitation Project, a study was conducted to develop weightless habitat configurations using systems based on International Space Station (ISS) designs. Two mission sizes are described for a 4-crew 60-day mission, and a 4-crew 500-day mission using standard Node, Lab, and Multi-Purpose Logistics Module (MPLM) sized elements, and ISS derived habitation systems. These durations were selected to explore the lower and upper bound for the exploration missions under consideration including a range of excursions within the Earth-Moon vicinity, near earth asteroids, and Mars orbit. Current methods for sizing the mass and volume for habitats are based on mathematical models that assume the construction of a new single volume habitat. In contrast to that approach, this study explored the use of ISS designs based on existing hardware where available and construction of new hardware based on ISS designs where appropriate. Findings included a very robust design that could be reused if the DSH were assembled and based at the ISS and a transportation system were provided for its return after each mission. Mass estimates were found to be higher than mathematical models due primarily to the use of multiple ISS modules instead of one new large module, but the maturity of the designs using flight qualified systems have potential for improved cost, schedule, and risk benefits.

  11. Measurements and Modelling of Base Station Power Consumption under Real Traffic Loads †

    OpenAIRE

    Goran Petrovic; Tonko Garma; Josip Lorincz

    2012-01-01

    Base stations represent the main contributor to the energy consumption of a mobile cellular network. Since traffic load in mobile networks significantly varies during a working or weekend day, it is important to quantify the influence of these variations on the base station power consumption. Therefore, this paper investigates changes in the instantaneous power consumption of GSM (Global System for Mobile Communications) and UMTS (Universal Mobile Telecommunications System) base stations acco...

  12. Reference Station Network Based RTK Systems-Concepts and Progress

    Institute of Scientific and Technical Information of China (English)

    C. Rizos; S. Han

    2003-01-01

    The limitation of single base "real-time kinematic"(RTK) techniques is the distance between base receiver and the rover receiver due to distance-dependent biases, namely orbit bias,ionosphere bias and troposphere bias. Techniques have been developed to overcome this distance dependence using a network of GPS reference stations spread over a wide geographic area. Because the measurement biases will be modelled and corrected for, the positioning accuracy will be almost independent of the inter-receiver distance.Since the mid-1990s investigators have been investigating the optimal means of processing reference receiver data, and then providing generally referred to as Network-RTK. In 1993 the International Association of Geodesy (IAG) established a Special Study Group on"Wide Area Modelling for Precise Satellite Positioning" . This paperfocusses on the progress made during the last few years in designing Network-RTK architectures and the associated data processing algorithms and issues. Although many university investigators have been researching the fundamental challenges in functional and stochastic modelling, currently there is only one commercially available Network-RTK product, the Trimble VRS. However, with the use of the Internet as the primary data communication link, it is predicted that various sites around the world, over the next few years.

  13. Data communications method for mobile network in fourth generation communications system, involves delivering decoded data to mobile station from relay station, where mobile station receives data from both relay and base stations

    DEFF Research Database (Denmark)

    2008-01-01

    The method involves utilizing a base station (BS) (100) to transmit data to a relay station (RS) (110) and a mobile station (MS) (120), where the data includes two messages. The BS is utilized to transmit the two messages by utilizing a linear combination method, and the data is received in the RS...... and decoded. The decoded data is delivered to the MS from the RS, where the RS transmits the decoded data by utilizing another linear combination method. The MS receives data from both the BS and the RS....

  14. ZTE Becomes Global Leader in CDMA Base Station Market with 33% Share

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    ZTE Corporation announced on November 3, 2011 that it has become the global leader in the CDMA base station market, with a 32.6 percent share in first half 2011. According to a recent IDC analytical report on the global CDMA market, ZTE has increased its shipments of CDMA base stations steadily in recent years. As of the end of first half of 2011, the company's shipment of base-stations had exceeded 320 thousand units, pushing it to the top spot in the global CDMA base station market.

  15. Radiofrequency ablation in dermatology

    Directory of Open Access Journals (Sweden)

    Sachdeva Silonie

    2007-01-01

    Full Text Available Radiofreqeuency ablation is a versatile dermatosurgical procedure used for surgical management of skin lesions by using various forms of alternating current at an ultra high frequency. The major modalities in radiofrequency are electrosection, electrocoagulation, electrodessication and fulguration. The use of radiofrequency ablation in dermatosurgical practice has gained importance in recent years as it can be used to treat most of the skin lesions with ease in less time with clean surgical field due to adequate hemostasis and with minimal side effects and complications. This article focuses on the major tissue effects and factors influencing radiofrequency ablation and its application for various dermatological conditions.

  16. MOBILE POWER STATIONS BASED ON AIRCRAFT GAS-TURBINE ENGINES

    OpenAIRE

    Kavelin, V.; National Aviation University, Kyiv

    2012-01-01

     Gas-turbine power station is a modern, high-technology plant, which generates electricity and heat energy. It consists of one or more gas-turbine engines – power-plants ganged with electric generator and combined into one power complex by controlling system. Mobile power stations are used in districts, which are distant from source of electric power, e.g. during building of waterworks, mines, bore-holes drilling etc. Primary purpose of mobile power stations is their usage as emergency source...

  17. Are people living next to mobile phone base stations more strained? Relationship of health concerns, self-estimated distance to base station, and psychological parameters

    OpenAIRE

    Augner Christoph; Hacker Gerhard

    2009-01-01

    Background and Aims: Coeval with the expansion of mobile phone technology and the associated obvious presence of mobile phone base stations, some people living close to these masts reported symptoms they attributed to electromagnetic fields (EMF). Public and scientific discussions arose with regard to whether these symptoms were due to EMF or were nocebo effects. The aim of this study was to find out if people who believe that they live close to base stations show psychological or psychobiol...

  18. Small Dosimeter based on Timepix device for International Space Station

    Science.gov (United States)

    Turecek, D.; Pinsky, L.; Jakubek, J.; Vykydal, Z.; Stoffle, N.; Pospisil, S.

    2011-12-01

    The radiation environment in space is different, more complex and more intense than on Earth. Conventional devices and detection methods used nowadays do not allow to discriminate single particle types and the energy of the single particles. The Timepix detector is a position sensitive pixelated detector developed at CERN in a frame of the Medipix collaboration that provides capability to visualize tracks and measure energy of single particles. This information can be used for sorting the particles into different categories. It is possible to distinguish light charged particles such as electrons or heavy charged particles such as ions. Moreover, the Linear Energy Transfer (LET) for charged particles can be determined. Each category is assigned a quality factor corresponding to the energy a particle would deposit in the human tissue. By summing the dose of all particles an estimate of the dose rate can be calculated. For space dosimetry purposes a miniature device with the Timepix detector and a custom made integrated USB based readout interface has been constructed. The entire device has dimensions of a USB flash memory stick. The whole compact device is connected to a control PC and is operated continuously. The PC runs a software that controls data acquisition, adjusts the acquisition time adaptively according to the particle rate, analyzes the particle tracks, evaluates the deposited energy and the LET and visualizes in a simple display the estimated dose rate. The performance of the device will be tested during a mission on International Space Station planned towards the beginning of year 2012.

  19. Sustainable Power Supply Solutions for Off-Grid Base Stations

    Directory of Open Access Journals (Sweden)

    Asma Mohamad Aris

    2015-09-01

    Full Text Available The telecommunication sector plays a significant role in shaping the global economy and the way people share information and knowledge. At present, the telecommunication sector is liable for its energy consumption and the amount of emissions it emits in the environment. In the context of off-grid telecommunication applications, off-grid base stations (BSs are commonly used due to their ability to provide radio coverage over a wide geographic area. However, in the past, the off-grid BSs usually relied on emission-intensive power supply solutions such as diesel generators. In this review paper, various types of solutions (including, in particular, the sustainable solutions for powering BSs are discussed. The key aspects in designing an ideal power supply solution are reviewed, and these mainly include the pre-feasibility study and the thermal management of BSs, which comprise heating and cooling of the BS shelter/cabinets and BS electronic equipment and power supply components. The sizing and optimization approaches used to design the BSs’ power supply systems as well as the operational and control strategies adopted to manage the power supply systems are also reviewed in this paper.

  20. Optimization of Base Station and Maximizing the Lifetime of Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    P.Parthiban

    2014-05-01

    Full Text Available Maximizing the Wireless Sensor Networks (WSNs lifetime is one of the most remarkable studies in the academic and the industrial research. In the existing Base station locations, the sensor network lifetime is short due to higher energy consumption. Higher energy consumption is due to the non-optimized location of base station. Non optimized location increases the distance between the sensor nodes to the base station, so it will not transfer the data directly to the base station. Each node transfer the data to the neighbor node and finally it reaches the base station. Due to transferring of the data to the neighbor node increases the data rate step by step and also the number of sensor nodes increases the optimal location of base station to become complex. So the main objective is to find optimal base station location to reduce energy consumption and to maximize the network’s lifetime in wireless sensor networks and to find the optimal path for all sensor nodes to the base station to analyze its lifetime. In this paper, an algorithm based on Gravity Location Model and data routing based on particle swarm optimization (PSO are thus proposed for efficient energy consumption and data routing.

  1. Results of a cross-sectional study on the association of electromagnetic fields emitted from mobile phone base stations and health complaints

    International Nuclear Information System (INIS)

    Background: Despite the fact that adverse health effects are not confirmed for exposure to radiofrequency electromagnetic field (RFEMF) levels below the limit values, as defined in the guidelines of the International Commission on Non-Ionizing Radiation Protection, many persons are worried about possible adverse health effects caused by the RF-EMF emitted from mobile phone base stations, or they attribute their unspecific health complaints like headache or sleep disturbances to these fields. Method: In the framework of a cross-sectional study a questionnaire was sent to 4150 persons living in predominantly urban areas. Participants were asked whether base stations affected their health. Health complaints were measured with standardized health questionnaires for sleep disturbances, headache, health complaints and mental and physical health. 3,526 persons responded (85%) to the questionnaire and 1,808 (51%) agreed to dosimetric measurements in their flats. Exposure was measured in 1,500 flats. Results: The measurements accomplished in the bedrooms in most cases showed very low exposure values, most often below sensitivity limit of the dosimeter. An association of exposure with the occurrence of health complaints was not found, but an association between the attribution of adverse health effects to base stations and the occurrence of health complaints. Conclusions: However, concerns about health and the attribution of adverse health effects to these mobile phone base stations should be taken serious and require a risk communication with concerned persons. Future research should focus on the processes of perception and appraisal of RF-EMF risks, and ascertain the determinants of concerns and attributions in the context of RF-EMF. (orig.)

  2. Radiation level survey of a mobile phone base station

    International Nuclear Information System (INIS)

    Electromagnetic field (E.M.F.) evaluations were carried out in the surroundings of a roof-top mobile-phone radio-base station (R.B.S.). Four of its sector-panel antennas are installed on two parallel vertical masts, each supporting two panels in a vertical collinear-array. The geometry is such that the vertical plane containing both masts is about 10 meters distant and parallel to the backside of an educational institution. This proximity provoked great anxiety among the local community members regarding potential health hazards.1. Introduction: To keep up with the expansion of the mobile-phone services, the number of Radio-Base Stations (R.B.S.) installations is increasing tremendously in Brazil. Efficient control and radiation monitoring to assess R.B.S. compliance to existing regulations are still lacking and particularly in big cities, clearly non - compliant R.B.S. can be seen which represent potentially hazardous E.M.F. sources to the nearby population. This first survey of an irregular R.B.S. revealed significant E-field strengths outside, as well as inside a classroom of an educational building where an usually prolonged stay is necessary. These results confirm that this problem deserves further attention, moreover, if one considers that public and occupational exposure limits set by I.C.N.I.R.P. (also adopted in Brazil) are exclusively based on the immediate thermal effects of acute exposure, disregarding any potential health risk from prolonged exposure to lower level radiation. Research activities focusing on quantitative aspects of electromagnetic radiation from R.B.S., as well as on biological and adverse health effects are still at a very incipient level, urging for immediate actions to improve this scenario in our country. 2. Material, methods and results Measurements were carried out with a broadband field strength monitor, E.M.R.-300 (W and G) coupled to an isotropic E-field probe (100 khz to 3 GHz). Preliminary measurements helped locating

  3. Measurements of MIMO Indoor Channels at 1800 MHz with Multiple Indoor and Outdoor Base Stations

    Directory of Open Access Journals (Sweden)

    Jaldén Niklas

    2007-01-01

    Full Text Available This paper proposes several configurations for multiple base stations in indoor MIMO systems and compares their performance. The results are based on channel measurements realized with a MIMO testbed. The receiver was moved along several routes and floors on an office building. Both outdoor and indoor locations are considered for the transmitters or base stations, which allow the analysis of not only indoor but also outdoor-to-indoor environment. The use of 2 base stations with different system level combinations of the two is analyzed. We show that the configuration with base station selection provides almost as good performance as a full water-filling scheme when the 2 base stations are placed at different locations. Also the spatial correlation properties for the different configurations are analyzed and the importance of considering path loss when evaluating capacity is highlighted.

  4. Computer based training simulator for Hunterston Nuclear Power Station

    International Nuclear Information System (INIS)

    For reasons which are stated, the Hunterston-B nuclear power station automatic control system includes a manual over-ride facility. It is therefore essential for the station engineers to be trained to recognise and control all feasible modes of plant and logic malfunction. A training simulator has been built which consists of a replica of the shutdown monitoring panel in the Central Control Room and is controlled by a mini-computer. This paper highlights the computer aspects of the simulator and relevant derived experience, under the following headings: engineering background; shutdown sequence equipment; simulator equipment; features; software; testing; maintenance. (U.K.)

  5. Improving the efficiency of measurement procedures for assessing human exposure in the vicinity of mobile phone (GSM/DCS/UMTS) base stations

    International Nuclear Information System (INIS)

    Standards stipulate 6-min time interval of averaging for measurements of radio-frequency electromagnetic fields to assess human exposure to non-ionising radiation. Having in mind the base stations of public land mobile systems, the time interval defined in such a way noticeably limits the number of measuring points in practical applications. In this paper, based on the results of measurements in the vicinity of a multisystem base station (Global System for Mobile Communications [GSM], Digital Communication System [DCS] and Universal Mobile Telecommunications System [UMTS]), it was shown that the measurement process can be significantly accelerated by using shorter time intervals of averaging-15 s, 30 s and 1 min. It was found that measurement results differed from the 6-min root-mean-square mean by 10.5 %, 15.9 and 19 %, respectively, while the uncertainty of the measurements was increased by 3.0 %, 3.8 and 4.4 %, respectively. Shorter time-averaging intervals would reduce the total duration of the exposure assessment survey, while not compromising too much on measurement quality. (authors)

  6. Analysis of the disturbance voltage and gpr in substation and mobile base station co-construction

    Directory of Open Access Journals (Sweden)

    Long Jie

    2016-01-01

    Full Text Available It is essential to consider the electrical safety protection distance when the mobile base station and the substation are building together. This paper makes an analysis from three aspects: the influence on the disturbance voltage of the secondary cable in substation when the station is struck by lightning; the influence on the base station grounding grid caused by the station switching operation and short circuit faults. According to the relevant national and international standards, the electrical parameters are calculated when the substation and mobile base station grounding grid connected in different ways and different distance. The conclusion of the paper provides a theoretical basis for engineering construction with much higher practical value. Meanwhile, it is of great significance to develop the win-win co-operation between the power and telecommunications operators and to explore the diversified businesses of electric power.

  7. A SILICON LDMOS BASED RF POWER AMPLIFIER FOR WIRELESS BASE STATION APPLICATIONS

    Directory of Open Access Journals (Sweden)

    Thiyagarajan Krishnan

    2013-10-01

    Full Text Available Radio Frequency Power amplifier is one of the essential module in the transmission chain of wireless Base stations. There is always a trade-off exists between power efficiency and linearity of the power amplifier. The design of power amplifier using LDMOS based active devices will give cost-effective solution. This work presents the design of a Class A power amplifier for unlicensed ISM band wireless Base station requirements. The design is carried out using Si-LDMOS (Silicon - Laterally Diffused Metal Oxide Semiconductor technology and is built on Epoxy-FR4 (Flame Retardant, woven glass reinforced epoxy resin board with a dielectric constant of 4.6 and substrate thickness of 1.6 mm. The amplifier design uses Free scale Si-LDMOS MW6S004NT1 transistor model in Agilent’s Advanced Design System (ADS 2011. The simulation was carried out to analyze the behaviour of power amplifier in the 2.4GHz ISM band. The simulated results has shown an acceptable behaviour with a gain of 16.558 dB, power added efficiency of 61.897% at 2.4 GHz, which allow the use of the device in the wireless base station application requirements.

  8. Public exposure to radio waves near GSM microcell and picocell base stations

    International Nuclear Information System (INIS)

    Exposures of the general public to radio waves at locations near 20 randomly selected GSM microcell and picocell base stations in the UK have been assessed in the context of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Compliance distances were calculated for the antennas of the base stations from their reported radiated powers. Under pessimistic assumptions that would maximise exposures, the minimum height at which the general public reference level could potentially be exceeded near any of the base station antennas was calculated to be 2.4 m above ground level. The power densities of the broadcast carriers transmitted by the base stations have been measured and scaled to include all other possible carriers. Exposures were generally in the range 0.002-2% of the ICNIRP general public reference level, and the greatest exposure quotient near any of the base stations was 8.6%. Exposures close to microcell base stations were found to be generally greater than those close to macrocell base stations

  9. Radio-frequency integrated-circuit engineering

    CERN Document Server

    Nguyen, Cam

    2015-01-01

    Radio-Frequency Integrated-Circuit Engineering addresses the theory, analysis and design of passive and active RFIC's using Si-based CMOS and Bi-CMOS technologies, and other non-silicon based technologies. The materials covered are self-contained and presented in such detail that allows readers with only undergraduate electrical engineering knowledge in EM, RF, and circuits to understand and design RFICs. Organized into sixteen chapters, blending analog and microwave engineering, Radio-Frequency Integrated-Circuit Engineering emphasizes the microwave engineering approach for RFICs. Provide

  10. A graphical user interface-based instructor station

    International Nuclear Information System (INIS)

    Instructor Stations are an important part of CAE's full-scope Nuclear Power Plant Simulators. CAE's current generation of Instructor Station, through use of a proven Graphical User Interface (GUI) combined with an advanced hardware platform, provides the instructor with a very powerful training tool. Several features are available to provide the instructor with tools for effective operator training. For example, to track simulator status, the Graphic Recorder can record, on disk, several hours of data for up to 48 user-defined points. This data can be plotted while being recorded, and replayed after recording has completed. Another feature, provided by the Lesson Plan Editor/Executive, allows the instructor to conveniently build a set of repeatable lessons, made up of specific Instructor actions, to be used as a Lesson Plan step. This paper examines how the most advanced hardware and software tools were implemented to produce a state-of-the-art Instructor Station satisfying the required design goals set by the customers and CAE for its Instructor Facilities

  11. Perceived externalities of cell phone base stations: the case of property prices in Hamburg, Germany

    OpenAIRE

    Brandt, Sebastian; Maennig, Wolfgang

    2012-01-01

    We examine the impact of cell phone base stations on prices of condominiums in Hamburg, Germany. This is the first hedonic study on this subject for housing prices in Europe and the first ever to examine the price impact of base stations within a whole metropolis. We distinguish between individual masts and groups of masts. On the basis of a dataset of over 1000 base stations set up in Hamburg, we find that only immediate proximity to groups of antenna masts is perceived as harmful by residen...

  12. Determination of the regional deformation rates of Shanghai and Kashima VLBI stations based on ITRF97

    Science.gov (United States)

    Yang, Zhi-gen; Zhu, Wen-yao; Shum, C. K.; Shu, Feng-chun

    The vertical deformation rates (VDRs) and horizontal deformation rates (HDRs) of Shanghai VLBI station in China and Kashima and Kashima34 VLBI stations in Japan were re-analysed using the baseline length change rates from Shanghai to 13 global VLBI stations, and from Kashima to 27 stations and from Kashima34 to 12 stations, based on the NASA VLBI global solution glb1123 (Ma, 1999). The velocity vectors of the global VLBI stations were referred to the ITRF97 reference frame, and the Eulerian vectors of different models of plate motion were used for comparative solutions. The VDR of Shanghai station is estimated to be -1.91±0.56 mm/ yr, and those of Kashima and Kashima34 stations, -3.72±0.74 mm/ yr and -8.81±0.84 mm/ yr, respectively. The difference between the last two was verified by further analysis. Similar estimates were also made for the Kokee, Kauai and MK_VLBA VLBI stations in mid-Pacific.

  13. Investigation of high sensitivity radio-frequency readout circuit based on AlGaN/GaN high electron mobility transistor

    Science.gov (United States)

    Zhang, Xiao-Yu; Tan, Ren-Bing; Sun, Jian-Dong; Li, Xin-Xing; Zhou, Yu; Lü, Li; Qin, Hua

    2015-10-01

    An AlGaN/GaN high electron mobility transistor (HEMT) device is prepared by using a semiconductor nanofabrication process. A reflective radio-frequency (RF) readout circuit is designed and the HEMT device is assembled in an RF circuit through a coplanar waveguide transmission line. A gate capacitor of the HEMT and a surface-mounted inductor on the transmission line are formed to generate LC resonance. By tuning the gate voltage Vg, the variations of gate capacitance and conductance of the HEMT are reflected sensitively from the resonance frequency and the magnitude of the RF reflection signal. The aim of the designed RF readout setup is to develop a highly sensitive HEMT-based detector. Project supported by the National Natural Science Foundation of China (Grant No. 61107093), the Suzhou Science and Technology Project, China (Grant No. ZXG2012024), and the Youth Innovation Promotion Association, Chinese Academy of Sciences (Grant No. 2012243).

  14. Vol. 33 - Compact State-Space Models for Complex Superconducting Radio-Frequency Structures Based on Model Order Reduction and Concatenation Methods

    CERN Document Server

    Flisgen, Thomas

    2015-01-01

    The modeling of large chains of superconducting cavities with couplers is a challeng- ing task in computational electrical engineering. The direct numerical treatment of these structures can easily lead to problems with more than ten million degrees of freedom. Problems of this complexity are typically solved with the help of parallel programs running on supercomputing infrastructures. However, these infrastructures are expensive to purchase, to operate, and to maintain. The aim of this thesis is to introduce and to validate an approach which allows for modeling large structures on a standard workstation. The novel technique is called State-Space Concatena- tions and is based on the decomposition of the complete structure into individual segments. The radio-frequency properties of the generated segments are described by a set of state-space equations which either emerge from analytical considera- tions or from numerical discretization schemes. The model order of these equations is reduced...

  15. Synthesis of Bio-Compatible SPION–based Aqueous Ferrofluids and Evaluation of RadioFrequency Power Loss for Magnetic Hyperthermia

    Directory of Open Access Journals (Sweden)

    Sakthikumar D

    2010-01-01

    Full Text Available Abstract Bio-compatible magnetic fluids having high saturation magnetization find immense applications in various biomedical fields. Aqueous ferrofluids of superparamagnetic iron oxide nanoparticles with narrow size distribution, high shelf life and good stability is realized by controlled chemical co-precipitation process. The crystal structure is verified by X-ray diffraction technique. Particle sizes are evaluated by employing Transmission electron microscopy. Room temperature and low-temperature magnetic measurements were carried out with Superconducting Quantum Interference Device. The fluid exhibits good magnetic response even at very high dilution (6.28 mg/cc. This is an advantage for biomedical applications, since only a small amount of iron is to be metabolised by body organs. Magnetic field induced transmission measurements carried out at photon energy of diode laser (670 nm exhibited excellent linear dichroism. Based on the structural and magnetic measurements, the power loss for the magnetic nanoparticles under study is evaluated over a range of radiofrequencies.

  16. Collaborative online knowledge base for human planetary mission simulation stations

    Science.gov (United States)

    Hargitai, H. I.

    2008-09-01

    Mars Society operates two Mars simulation research stations since 2001/2002: one in Devon Island (FMARS) and one in Utah (MDRS). The goal of these stations is to simulate human mission - work and life - on the Surface of Mars. FMARS receives one crew each year while at MDRS crews change every second week except for the summer season. In the last 7 years 71 crews worked at MDRS. Their results are published in various forums: in peer-reviewed papers, conference abstracts, books, private websites or other publications [3]. The actual work of all crews is documented as specialized daily reports together with images and are avaiable at the MDRS website [4] (Fig. 1, Fig. 2.). An important part of these reports are the "lessons learned" sections where crews describe what they have learned during field trips (EVAs) or other activities. Updated operation manuals and cartographic resources [1] are also available on the website. Some of crew members are visiting MDRS for the first time, others are "veterans".

  17. Improved social force model based on exit selection for microscopic pedestrian simulation in subway station

    Institute of Scientific and Technical Information of China (English)

    郑勋; 李海鹰; 孟令云; 许心越; 陈旭

    2015-01-01

    An improved social force model based on exit selection is proposed to simulate pedestrians’ microscopic behaviors in subway station. The modification lies in considering three factors of spatial distance, occupant density and exit width. In addition, the problem of pedestrians selecting exit frequently is solved as follows: not changing to other exits in the affected area of one exit, using the probability of remaining preceding exit and invoking function of exit selection after several simulation steps. Pedestrians in subway station have some special characteristics, such as explicit destinations, different familiarities with subway station. Finally, Beijing Zoo Subway Station is taken as an example and the feasibility of the model results is verified through the comparison of the actual data and simulation data. The simulation results show that the improved model can depict the microscopic behaviors of pedestrians in subway station.

  18. Energy-aware base stations: The effect of planning, management, and femto layers

    OpenAIRE

    G. Koutitas; Chiaraviglio, L; Delia Ciullo; Meo, M; Tassiulas, L.

    2014-01-01

    We compare the performance of three base station management schemes on three different network topologies. In addition, we explore the effect of offloading traffic to heterogeneous femtocell layer upon energy savings taking into account the increase of base station switch-off time intervals. Fairness between mobile operator and femtocell owners is maintained since current femtocell technologies present flat power consumption curves with respect to served traffic. We model two different user-t...

  19. Effect of electromagnetic radiations from mobile phone base stations on general health and salivary function

    OpenAIRE

    Singh, Kushpal; Nagaraj, Anup; Yousuf, Asif; Ganta, Shravani; Pareek, Sonia; Vishnani, Preeti

    2016-01-01

    Objective: Cell phones use electromagnetic, nonionizing radiations in the microwave range, which some believe may be harmful to human health. The present study aimed to determine the effect of electromagnetic radiations (EMRs) on unstimulated/stimulated salivary flow rate and other health-related problems between the general populations residing in proximity to and far away from mobile phone base stations. Materials and Methods: A total of four mobile base stations were randomly selected from...

  20. PREDICTION OF EXPOSURE CONDITIONS IN VICINITY OF UMTS BASE STATION ANTENNAS

    OpenAIRE

    Wojcik, D

    2007-01-01

    The rapid diffusion of wireless telecommunications has focused attention on potential risks for human health due to the exposure to electromagnetic (EM) fields. In context of cellular telephony the problem should be considered in two different aspects: possible health hazard due to hand-held phone devices or due to base station antennas, which this paper will be devoted to. To evaluate exposure condition in vicinity of Universal Mobile Telecommunication System (UMTS) base station antenna, the...

  1. Radiofrequency electromagnetic fields in the Cookridge area of Leeds

    International Nuclear Information System (INIS)

    On the 8 and 9 May 2002 representatives of the National Radiological Protection Board (NRPB) performed a radiofrequency electromagnetic field survey in the Cookridge area of Leeds in order to assess exposure to radio signals from transmitters mounted on a water tower/a lattice tower and a radio station tower. Guidelines on limiting exposure to radio signals have been published by NRPB and the International Commission on Non-Ionizing Radiation Protection (ICNIRP). These guidelines are designed to prevent established adverse effects on human health. During this survey, the total exposures due to all radio signals from 30 MHz to 18000 MHz (18 GHz) were measured. This frequency range was chosen as it includes mobile phone base station transmissions, which are at around 900 and 1800 MHz and super high frequency (SHF) transmissions from most of the large microwave dish antennas mounted on the towers. In addition, other major sources of radiofrequency electromagnetic fields in the environment such as broadcast radio and television transmissions are included in this range. Measurements of power density were made at eight locations in the vicinity of the transmitter sites. Comparison of the measurements with the guidelines showed that the total exposure from radio signals measured between 30 MHz and 18 GHz ranged from 0.26 millionths (0.000026%) to 190 millionths (0.019%) of the NRPB investigation level and from 1.6 millionths (0.00016%) to 1400 millionths (0.14%) of the ICNIRP reference level for exposure of the general public. All the measured exposures are therefore many times below guideline levels and are not considered hazardous. (author)

  2. Are people living next to mobile phone base stations more strained? Relationship of health concerns, self-estimated distance to base station, and psychological parameters

    Directory of Open Access Journals (Sweden)

    Augner Christoph

    2009-01-01

    Full Text Available Background and Aims: Coeval with the expansion of mobile phone technology and the associated obvious presence of mobile phone base stations, some people living close to these masts reported symptoms they attributed to electromagnetic fields (EMF. Public and scientific discussions arose with regard to whether these symptoms were due to EMF or were nocebo effects. The aim of this study was to find out if people who believe that they live close to base stations show psychological or psychobiological differences that would indicate more strain or stress. Furthermore, we wanted to detect the relevant connections linking self-estimated distance between home and the next mobile phone base station (DBS, daily use of mobile phone (MPU, EMF-health concerns, electromagnetic hypersensitivity, and psychological strain parameters. Design, Materials and Methods: Fifty-seven participants completed standardized and non-standardized questionnaires that focused on the relevant parameters. In addition, saliva samples were used as an indication to determine the psychobiological strain by concentration of alpha-amylase, cortisol, immunoglobulin A (IgA, and substance P. Results: Self-declared base station neighbors (DBS ≤ 100 meters had significantly higher concentrations of alpha-amylase in their saliva, higher rates in symptom checklist subscales (SCL somatization, obsessive-compulsive, anxiety, phobic anxiety, and global strain index PST (Positive Symptom Total. There were no differences in EMF-related health concern scales. Conclusions: We conclude that self-declared base station neighbors are more strained than others. EMF-related health concerns cannot explain these findings. Further research should identify if actual EMF exposure or other factors are responsible for these results.

  3. Design of Three Phase Solar-Based 4.5kw Ac Power Inverter Station

    OpenAIRE

    Dr. J. C. Onuegbu

    2013-01-01

    The design model of a 4.50Kilowatt, 3-phase, 50 hertz solar-based power generating station was examined by the paper. The power station is a dual source input generating station using 8 series connected 100A, 12V batteries per phase as backup, the solar panels being the main frame. An inverter of 12Volt direct current input voltage was incorporated to supply an output of 3-phase, 220Volts and 50 hertz alternating current. A charging circuit was installed to monitor charging level and to pres...

  4. Implementation of a Smart Antenna Base Station for Mobile WiMAX Based on OFDMA

    OpenAIRE

    Seungheon Hyeon; Changhoon Lee; Chang-eui Shin; Seungwon Choi

    2009-01-01

    We present an implementation of a mobile-WiMAX (m-WiMAX) base station (BS) that supports smart antenna (SA) functionality. To implement the m-WiMAX SA BS, we must address a number of key issues in baseband signal processing related to symbol-timing acquisition, the beamforming scheme, and accurate calibration. We propose appropriate solutions and implement an m-WiMAX SA BS accordingly. Experimental tests were performed to verify the validity of the solutions. Results showed a 3.5-time (5.5&#...

  5. Performance evaluation of telemetry stations based on site selection (Short Communication)

    OpenAIRE

    M. Goswami; B. Sucharita; P. Arya

    2003-01-01

    In a test range, selection of sites for deployment of mobile telemetry stations plays a crucial role for acquiring and tracking any airborne vehicle under test. Efforts have been made to correlate the tracking performance of the auto track stations based on site selection for various test flights conducted from different launching pads. Some of the tracking methodologies discussed in this paper are single channel amplitude comparison monopulse (SCACMP) technique and E-SCAN technique. A...

  6. Novel Radio on Fiber Access Eliminating External Electric Power Supply at Base Station

    Institute of Scientific and Technical Information of China (English)

    Tetsuya; Miki; Katsuyasu; Kawano; Nobuo; Nakajima; Naoto; Kishi; Masaru; Miyamoto; Tetsu; Aoki

    2003-01-01

    A novel Radio On Fiber(ROF) access is proposed and demonstrated which enables the pico-cell Base Station (BS) for high-speed wireless communications to eliminate external electric power supply facilities. We demonstrated 2.4-GHz band radio signal transmission through the BS without external electric power supply. The electrical power used for BS circuit is feeded by optical power over optical fiber from central station.

  7. A Photovoltaic Power Station Equivalent Method Based on Real-Time Digital Simulator

    Directory of Open Access Journals (Sweden)

    Yang Ping

    2016-01-01

    Full Text Available As a clean energy power generation technology, photovoltaic generation has the characteristics of low carbon, green and environmental protection. More and more countries pay close attention to it, more than one megawatt demonstration projects of grid photovoltaic power station has been commenced or built. In order to study interconnection characteristics of large-scale photovoltaic power station better, reduce the effects of photovoltaic power station to the grid, we need to set up photovoltaic power station simulation model. However, the model of photovoltaic power station is complex, the speed of system simulation become slow after establish. In this paper, a real-time digital simulator based on the photovoltaic power station equivalent method will be given, through the proposed hierarchical equivalence method can simplify the process of equivalent of photovoltaic power station, shortening the period of equivalent model, and can be carried out in the process of each layer of the equivalent model accuracy validation, improve the accuracy of the equivalent model.

  8. Design of a Base Station for MEMS CCR Localization in an Optical Sensor Network

    Directory of Open Access Journals (Sweden)

    Chan Gook Park

    2014-05-01

    Full Text Available This paper introduces a design and implementation of a base station, capable of positioning sensor nodes using an optical scheme. The base station consists of a pulse laser module, optical detectors and beam splitter, which are mounted on a rotation-stage, and a Time to Digital Converter (TDC. The optical pulse signal transmitted to the sensor node with a Corner Cube Retro-reflector (CCR is reflected to the base station, and the Time of Flight (ToF data can be obtained from the two detectors. With the angle and flight time data, the position of the sensor node can be calculated. The performance of the system is evaluated by using a commercial CCR. The sensor nodes are placed at different angles from the base station and scanned using the laser. We analyze the node position error caused by the rotation and propose error compensation methods, namely the outlier sample exception and decreasing the confidence factor steadily using the recursive least square (RLS methods. Based on the commercial CCR results, the MEMS CCR is also tested to demonstrate the compatibility between the base station and the proposed methods. The result shows that the localization performance of the system can be enhanced with the proposed compensation method using the MEMS CCR.

  9. Design of a base station for MEMS CCR localization in an optical sensor network.

    Science.gov (United States)

    Park, Chan Gook; Jeon, Hyun Cheol; Kim, Hyoun Jin; Kim, Jae Yoon

    2014-01-01

    This paper introduces a design and implementation of a base station, capable of positioning sensor nodes using an optical scheme. The base station consists of a pulse laser module, optical detectors and beam splitter, which are mounted on a rotation-stage, and a Time to Digital Converter (TDC). The optical pulse signal transmitted to the sensor node with a Corner Cube Retro-reflector (CCR) is reflected to the base station, and the Time of Flight (ToF) data can be obtained from the two detectors. With the angle and flight time data, the position of the sensor node can be calculated. The performance of the system is evaluated by using a commercial CCR. The sensor nodes are placed at different angles from the base station and scanned using the laser. We analyze the node position error caused by the rotation and propose error compensation methods, namely the outlier sample exception and decreasing the confidence factor steadily using the recursive least square (RLS) methods. Based on the commercial CCR results, the MEMS CCR is also tested to demonstrate the compatibility between the base station and the proposed methods. The result shows that the localization performance of the system can be enhanced with the proposed compensation method using the MEMS CCR. PMID:24815681

  10. Exposure to radio-frequency electromagnetic fields from broadcast transmitters and risk of childhood cancer: a census-based cohort study.

    Science.gov (United States)

    Hauri, Dimitri D; Spycher, Ben; Huss, Anke; Zimmermann, Frank; Grotzer, Michael; von der Weid, Nicolas; Spoerri, Adrian; Kuehni, Claudia E; Röösli, Martin

    2014-04-01

    We investigated the association between exposure to radio-frequency electromagnetic fields (RF-EMFs) from broadcast transmitters and childhood cancer. First, we conducted a time-to-event analysis including children under age 16 years living in Switzerland on December 5, 2000. Follow-up lasted until December 31, 2008. Second, all children living in Switzerland for some time between 1985 and 2008 were included in an incidence density cohort. RF-EMF exposure from broadcast transmitters was modeled. Based on 997 cancer cases, adjusted hazard ratios in the time-to-event analysis for the highest exposure category (>0.2 V/m) as compared with the reference category (<0.05 V/m) were 1.03 (95% confidence interval (CI): 0.74, 1.43) for all cancers, 0.55 (95% CI: 0.26, 1.19) for childhood leukemia, and 1.68 (95% CI: 0.98, 2.91) for childhood central nervous system (CNS) tumors. Results of the incidence density analysis, based on 4,246 cancer cases, were similar for all types of cancer and leukemia but did not indicate a CNS tumor risk (incidence rate ratio = 1.03, 95% CI: 0.73, 1.46). This large census-based cohort study did not suggest an association between predicted RF-EMF exposure from broadcasting and childhood leukemia. Results for CNS tumors were less consistent, but the most comprehensive analysis did not suggest an association. PMID:24651167

  11. Investigation of the exposure level of electromagnetic fields produced by mobile telephone base stations

    International Nuclear Information System (INIS)

    The aim of this work is to investigate the real values of microwave level distribution and propagation in the locality around samples of mobile phone base station, and to compare the results with the exposure restriction limits recommenced by the International Commission on Non Ionizing Radiation Protection (ICNIRP). Measurements were performed using special meters for microwaves; the first (Narda SRM-3000) is used for electromagnetic waves frequency spectrum scanning and the second (NARDA) emr 300) determine the level of electric and magnetic fields and the power density of these waves nearby any sort of transmitters. Samples of different kinds of mobile phone base station were chosen to cover important zones of Damascus, and the region around each base station was also scanned in the emission direction and according to accessibility into the studies positions. Results showed that the signal level in all measured points is lower than the ICNIRP restriction level, but for few points the detected microwave level has relatively important values. The signal level inside building situated partially in the emission direction of the base station transmitters decreases stepwise and walls reduce considerably the signal intensity. To realize these kind of field studies in the best way and obtain the maximum profits for all people, the properties and operating system of transmitters used in mobile phone base station must be known, and therefore, it is very important to achieve a transparent collaboration between research laboratory and mobile phone company. (author)

  12. Determination of exposure due to mobile phone base stations in an epidemiological study

    International Nuclear Information System (INIS)

    To investigate a supposed relationship between exposure by mobile phone base stations and well-being, an epidemiological cross sectional study is carried out within the German Mobile Telecommunication Research Program. In a parallel project, a method for the classification of electromagnetic exposure due to mobile phone base stations has been developed. This is based on the results of measurements of high frequency immissions in the interior of more than 1100 rooms and at outdoor locations, the calculation of the emissions of mobile phone antennas under free space propagation conditions and empirically determined transmission factors for the propagation of electromagnetic waves in different types of residential areas for passage of walls and windows. Standard tests (correlation-test, kappa-test, Bland-Altman-Plot, analysis of sensitivity and specificity) show that the method for computational exposure assessment developed in this project is applicable for a first classification of exposures due to mobile phone base stations in epidemiological studies. (authors)

  13. [The electromagnetic fields of the base stations of mobile radio communication and ecology. The estimation of danger of the base station EMF for population and for bioecosystems].

    Science.gov (United States)

    Grigor'ev, Iu G; Grigor'ev, K A

    2005-01-01

    The estimation of the danger for the population and for the bioecosistems of the electromagnetic conditions around of the base stations was given. The insufficiency of the scientific knowledge does not allow to guarantee the safety of the population and of the bioecosystems in the conditions of a round-the-clock long-term influence of EMF RF. WHO recommends to use "Precautionary principle". PMID:16454342

  14. A framework for recovery-oriented, COTS-based ground station networks

    Science.gov (United States)

    Cutler, James William

    The complexity of space communication has limited our access to space systems and kept mission operations costs high. Ultimately, this results in reduced mission capabilities and yields. In particular, ground stations, the access point between space and terrestrial networks, suffer from monolithic designs, narrow interfaces, and unreliability that raise significant financial barriers for low-cost, experimental satellite missions. This research reduces these barriers by developing technology for recovery-oriented, flexible access networks built from commercial-off-the-shelf (COTS) components. Based on our extensive small satellite experiences, we decomposed ground station services and captured them in an extensible framework that simplified reuse of ground station services and improved portability across heterogeneous installations. This capability, combined with selective customization through virtual machine technology, allowed us to deliver "just in time" ground stations for QuakeSat-1 at a fraction of the price of current commodity solutions. This decomposition is also informed by principles of robust system design. Thus, our ground station reference implementation called Mercury was a candidate for recursive recovery (RR), a high availability technique whose effectiveness in reducing recovery time has been demonstrated on research prototypes of Internet server systems. Augmenting Mercury to implement RR reduced recovery time of typical ground station software failures by a factor of four, dropping recovery time to within the "window of recovery" and effectively eliminating the adverse effects of these failures. Since the time of failures cannot be predicted, RR allowed us to mitigate the effects of the failures and greatly reduce their potential impact on ground station operations. Our ground station architecture harnessed the benefits of COTS components, including rapid prototyping and deployment, while overcoming the challenges of COTS reliability and mission

  15. Threshold-based prediction of the coagulation zone in sequential temperature mapping in MR-guided radiofrequency ablation of liver tumours

    International Nuclear Information System (INIS)

    To evaluate different cut-off temperature levels for a threshold-based prediction of the coagulation zone in magnetic resonance (MR)-guided radiofrequency (RF) ablation of liver tumours. Temperature-sensitive measurements were acquired during RF ablation of 24 patients with primary (6) and secondary liver lesions (18) using a wide-bore 1.5 T MR sytem and compared with the post-interventional coagulation zone. Temperature measurements using the proton resonance frequency shift method were performed directly subsequent to energy application. The temperature maps were registered on the contrast-enhanced follow-up MR images acquired 4 weeks after treatment. Areas with temperatures above 50 , 55 and 60 C were segmented and compared with the coagulation zones. Sensitivity and positive predictive value were calculated. No major complications occurred and all tumours were completely treated. No tumour recurrence was observed at the follow-up examination after 4 weeks. Two patients with secondary liver lesions showed local tumour recurrence after 4 and 7 months. The 60 C threshold level achieved the highest positive predictive value (87.7 ± 9.9) and the best prediction of the coagulation zone. For a threshold-based prediction of the coagulation zone, the 60 C cut-off level achieved the best prediction of the coagulation zone among the tested levels. (orig.)

  16. Nuclear modular power stations with lead-based coolant reactors

    International Nuclear Information System (INIS)

    In the present report, the projects of reactors with the lead-based coolant are considered. This class of reactors has the advantages and limitations. The main of advantages is enhanced safety and the main of restrictions is the limitation on power, both originate from natural properties of lead-based coolants. This limitation uniquely determines lead-technology reactors as medium - and small-power systems. (author)

  17. Anthropogenic radiofrequency electromagnetic fields as an emerging threat to wildlife orientation

    Energy Technology Data Exchange (ETDEWEB)

    Balmori, Alfonso, E-mail: balmaral@jcyl.es

    2015-06-15

    The rate of scientific activity regarding the effects of anthropogenic electromagnetic radiation in the radiofrequency (RF) range on animals and plants has been small despite the fact that this topic is relevant to the fields of experimental biology, ecology and conservation due to its remarkable expansion over the past 20 years. Current evidence indicates that exposure at levels that are found in the environment (in urban areas and near base stations) may particularly alter the receptor organs to orient in the magnetic field of the earth. These results could have important implications for migratory birds and insects, especially in urban areas, but could also apply to birds and insects in natural and protected areas where there are powerful base station emitters of radiofrequencies. Therefore, more research on the effects of electromagnetic radiation in nature is needed to investigate this emerging threat. - Highlights: • The growth of wireless telecommunication technologies causes increased electrosmog. • Radio frequency fields in the MHz range disrupt insect and bird orientation. • Radio frequency noise interferes with the primary process of magnetoreception. • Existing guidelines do not adequately protect wildlife. • Further research in this area is urgent.

  18. Anthropogenic radiofrequency electromagnetic fields as an emerging threat to wildlife orientation

    International Nuclear Information System (INIS)

    The rate of scientific activity regarding the effects of anthropogenic electromagnetic radiation in the radiofrequency (RF) range on animals and plants has been small despite the fact that this topic is relevant to the fields of experimental biology, ecology and conservation due to its remarkable expansion over the past 20 years. Current evidence indicates that exposure at levels that are found in the environment (in urban areas and near base stations) may particularly alter the receptor organs to orient in the magnetic field of the earth. These results could have important implications for migratory birds and insects, especially in urban areas, but could also apply to birds and insects in natural and protected areas where there are powerful base station emitters of radiofrequencies. Therefore, more research on the effects of electromagnetic radiation in nature is needed to investigate this emerging threat. - Highlights: • The growth of wireless telecommunication technologies causes increased electrosmog. • Radio frequency fields in the MHz range disrupt insect and bird orientation. • Radio frequency noise interferes with the primary process of magnetoreception. • Existing guidelines do not adequately protect wildlife. • Further research in this area is urgent

  19. Optimized Envelope Tracking Power Supply for Tetra2 Base Station RF Power Amplifier

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

    An ultra-fast tracking power supply (UFTPS) for envelope tracking in a 50kHz 64-QAM Tetra2 base station power amplification system is demonstrated. A simple method for optimizing the step response of the PID+PD sliding-mode control system is presented and demonstrated, along with a PLL-based scheme...

  20. Quality control of station-based soil moisture observations over Turkey

    Science.gov (United States)

    Tugrul Yilmaz, M.; Bulut, Burak; Cosh, Michael H.; Mladenova, Iliana

    2015-04-01

    Soil moisture is an essential variable in many hydrological applications like climate, drought, water and energy balance, weather prediction through its critical role in water and energy balance estimation. Soil moisture can be obtained using several different methods, like remote sensing-, station observation-, direct sampling-based. Station-based observations are widely used to validate satellite-based soil moisture products, making these observations to have very critical role in soil moisture estimation studies. Soil moisture observations are collected every 10 minutes since 2007 at 149 stations located over Turkey between 25.9°E - 41.8°E and 25.9°N - 41.8°N. These observation time-series are analyzed for the first time in this study for their consistency and reliability by classifying as "not reliable" and "reliable" after performing initially temperature correction and then quality control of the data.

  1. Base station selection for energy efficient network operation with the majorization-minimization algorithm

    CERN Document Server

    Pollakis, Emmanuel; Stańczak, Slawomir

    2012-01-01

    In this paper, we study the problem of reducing the energy consumption in a mobile communication network; we select the smallest set of active base stations that can preserve the quality of service (the minimum data rate) required by the users. In more detail, we start by posing this problem as an integer programming problem, the solution of which shows the optimal assignment (in the sense of minimizing the total energy consumption) between base stations and users. In particular, this solution shows which base stations can then be switched off or put in idle mode to save energy. However, solving this problem optimally is intractable in general, so in this study we develop a suboptimal approach that builds upon recent techniques that have been successfully applied to, among other problems, sparse signal reconstruction, portfolio optimization, statistical estimation, and error correction. More precisely, we relax the original integer programming problem as a minimization problem where the objective function is ...

  2. RF measurement made over 24 hours around mobile telephone base station (MTBS) in Malaysia

    International Nuclear Information System (INIS)

    The fact that so many people use of mobile phone has been accompanied by public debate about possible adverse effects on human health. The concern relate to the emissions of radiofrequency (RF) radiation from the mobile phone and from the MTBS that receive and transmit the signal. A study had been carried out by Nuclear Malaysia with aims to assess the levels of radiofrequency radiation and to analyze the radiation pattern against time for period of 24 hours. The finding of this study confirms that the MTBS transmit radiofrequency radiation with low level and vary against time. (Author)

  3. Online Ski Rental for ON/OFF Scheduling of Energy Harvesting, Millimeter Wave Base Stations

    OpenAIRE

    Lee, Gilsoo; Saad, Walid; Bennis, Mehdi; Mehbodniya, Abolfazl; Adachi, Fumiyuki

    2016-01-01

    The co-existence of millimeter wave (mmW) small cell base stations (SBSs) with conventional microwave macrocell base stations is a promising approach to boost the capacity and coverage of cellular networks. However, densifying the network with a viral deployment of mmW SBSs can significantly increase energy consumption. To reduce the reliance on unsustainable energy sources, one can adopt self-powered, mmW SBSs that rely solely on energy harvesting. Due to the uncertainty of energy arrival an...

  4. Novel Base Station MIMO Antennas with Enhanced Spectral Efficiencies Using Angular Reuse

    Directory of Open Access Journals (Sweden)

    Miguel Mora-Andreu

    2015-01-01

    Full Text Available The true polarization diversity (TPD technique is combined with the spatial diversity technique in novel MIMO antenna array geometries with a large number of elements. The use of a large number of elements requires some angular reuse within the array for polarization diversity. With designs compatible with existing base station antenna array configurations, the novel geometries with combining diversity schemes are shown to be able to achieve near the maximum spectral efficiencies. True polarization diversity (TPD schemes are found to be an excellent complement to more conventional spatial diversity schemes for obtaining optimum MIMO array performance in base station antennas.

  5. Radiation Measurement from Mobile Base Stations at a University Campus in Malaysia

    Directory of Open Access Journals (Sweden)

    Md. R. Islam

    2006-01-01

    Full Text Available The tremendous growth of telecommunication industry results the number of hand phone users increases everyday. In order to support the growing number of users, the mobile base stations can be seen in almost everywhere. This scenario has created uncomfortable feelings to the people that they may be affected by the radiations from antennas. A measurement was done at student hostels and office premises near to base stations in International Islamic University Malaysia, Gombak campus. Measured values are compared with Malaysian Communication and Multimedia Commission (MCMC, IEEE and ANSI recommendations for safety guidelines. The results are presented in this study.

  6. PV-solar / wind hybrid energy system for GSM/CDMA type mobile telephony base station

    OpenAIRE

    Pragya Nema, R.K. Nema, Saroj Rangnekar

    2010-01-01

    This paper gives the design idea of optimized PV-Solar and Wind Hybrid Energy System for GSM/CDMA type mobile base station over conventional diesel generator for a particular site in central India (Bhopal) . For this hybrid system ,the meteorological data of Solar Insolation, hourly wind speed, are taken for Bhopal-Central India (Longitude 77o.23'and Latitude 23o.21' ) and the pattern of load consumption of mobile base station are studied and suitably modeled for optimization of the hybrid en...

  7. Implementation of a Smart Antenna Base Station for Mobile WiMAX Based on OFDMA

    Directory of Open Access Journals (Sweden)

    Seungheon Hyeon

    2009-01-01

    Full Text Available We present an implementation of a mobile-WiMAX (m-WiMAX base station (BS that supports smart antenna (SA functionality. To implement the m-WiMAX SA BS, we must address a number of key issues in baseband signal processing related to symbol-timing acquisition, the beamforming scheme, and accurate calibration. We propose appropriate solutions and implement an m-WiMAX SA BS accordingly. Experimental tests were performed to verify the validity of the solutions. Results showed a 3.5-time (5.5 dB link-budget enhancement on the uplink compared to a single antenna system. In addition, the experimental results were consistent with the results of the computer simulation.

  8. The influence of the reflective environment on the absorption of a human male exposed to representative base station antennas from 300 MHz to 5 GHz

    International Nuclear Information System (INIS)

    The environment is an important parameter when evaluating the exposure to radio-frequency electromagnetic fields. This study investigates numerically the variation on the whole-body and peak spatially averaged-specific absorption rate (SAR) in the heterogeneous virtual family male placed in front of a base station antenna in a reflective environment. The SAR values in a reflective environment are also compared to the values obtained when no environment is present (free space). The virtual family male has been placed at four distances (30 cm, 1 m, 3 m and 10 m) in front of six base station antennas (operating at 300 MHz, 450 MHz, 900 MHz, 2.1 GHz, 3.5 GHz and 5.0 GHz, respectively) and in three reflective environments (a perfectly conducting wall, a perfectly conducting ground and a perfectly conducting ground + wall). A total of 72 configurations are examined. The absorption in the heterogeneous body model is determined using the 3D electromagnetic (EM) finite-difference time-domain (FDTD) solver Semcad-X. For the larger simulations, requirements in terms of computer resources are reduced by using a generalized Huygens' box approach. It has been observed that the ratio of the SAR in the virtual family male in a reflective environment and the SAR in the virtual family male in the free-space environment ranged from -8.7 dB up to 8.0 dB. A worst-case reflective environment could not be determined. ICNIRP reference levels not always showed to be compliant with the basic restrictions.

  9. The influence of the reflective environment on the absorption of a human male exposed to representative base station antennas from 300 MHz to 5 GHz

    Energy Technology Data Exchange (ETDEWEB)

    Vermeeren, G; Joseph, W; Martens, L [Ghent University-INTEC/IBBT, Gaston Crommenlaan 8 box 201, B-9050 Ghent (Belgium); Gosselin, M C; Kuehn, S; Kuster, N [IT' IS Foundation, Zurich (Switzerland); Kellerman, V; Meyer, F [EMSS, Stellenbosch (South Africa); Hadjem, A; Gati, A; Wiart, J, E-mail: Gunter.Vermeeren@intec.UGent.b [Orange Labs, Paris (France)

    2010-09-21

    The environment is an important parameter when evaluating the exposure to radio-frequency electromagnetic fields. This study investigates numerically the variation on the whole-body and peak spatially averaged-specific absorption rate (SAR) in the heterogeneous virtual family male placed in front of a base station antenna in a reflective environment. The SAR values in a reflective environment are also compared to the values obtained when no environment is present (free space). The virtual family male has been placed at four distances (30 cm, 1 m, 3 m and 10 m) in front of six base station antennas (operating at 300 MHz, 450 MHz, 900 MHz, 2.1 GHz, 3.5 GHz and 5.0 GHz, respectively) and in three reflective environments (a perfectly conducting wall, a perfectly conducting ground and a perfectly conducting ground + wall). A total of 72 configurations are examined. The absorption in the heterogeneous body model is determined using the 3D electromagnetic (EM) finite-difference time-domain (FDTD) solver Semcad-X. For the larger simulations, requirements in terms of computer resources are reduced by using a generalized Huygens' box approach. It has been observed that the ratio of the SAR in the virtual family male in a reflective environment and the SAR in the virtual family male in the free-space environment ranged from -8.7 dB up to 8.0 dB. A worst-case reflective environment could not be determined. ICNIRP reference levels not always showed to be compliant with the basic restrictions.

  10. The data platform of national special environment and disaster field observation stations based on grid environment

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The Data Platform of Resource and Environment-whose data mainly come from field observation stations,spatial observations,and internet service institutions-is the base of data analysis and model simulation in geoscience research in China.Among this integrated data platform,the tasks of the data platform of field observation stations are principally data collection,management,assimilation,and share service.Taking into consideration the distributing characteristics of the data sources and the service objects,the authors formulated the framework of the field observation stations’ data platform based on the grid technology and designed its operating processes.The authors have further defined and analyzed the key functions and implementing techniques for each module.In a Linux operating system,validation tests for the data platform’s function on data replication,data synchronization,and unified data service have been conducted under an environment that of the simulating field stations.

  11. Computer-based systems for nuclear power stations

    International Nuclear Information System (INIS)

    The published intentions of vendors are for extensive touch-screen control and computer-based protection. The software features needed for acceptance in the UK are indicated. The defence in depth needed is analyzed. Current practice in aircraft flight control systems and the software methods available are discussed. Software partitioning and mathematically formal methods are appropriate for the structures and simple logic needed for nuclear power applications. The potential for claims of diversity and independence between two computer-based subsystems of a protection system is discussed. Features needed to meet a single failure criterion applied to software are discussed. Conclusions are given on the main factors which a design should allow for. The work reported was done for the Health and Safety Executive of the UK (HSE), and acknowledgement is given to them, to NNC Ltd and to GEC-Marconi Avionics Ltd for permission to publish. The opinions and recommendations expressed are those of the authors and do not necessarily reflect those of HSE. (Author)

  12. Pedestrian movement analysis in transfer station corridor: Velocity-based and acceleration-based

    Science.gov (United States)

    Ji, Xiangfeng; Zhang, Jian; Hu, Yongkai; Ran, Bin

    2016-05-01

    In this paper, pedestrians are classified into aggressive and conservative ones by their temper. Aggressive pedestrians' walking through crowd in transfer station corridor is analyzed. Treating pedestrians as particles, this paper uses the modified social force model (MSFM) as the building block, where forces involve self-driving force, repulsive force and friction force. The proposed model in this paper is a discrete model combining the MSFM and cellular automata (CA) model, where the updating rules of the CA are redefined with MSFM. Due to the continuity of values generated by the MSFM, we use the fuzzy logic to discretize the continuous values into cells pedestrians can move in one step. With the observation that stimulus around pedestrians influences their acceleration directly, an acceleration-based movement model is presented, compared to the generally reviewed velocity-based movement model. In the acceleration-based model, a discretized version of kinematic equation is presented based on the acceleration discretized with fuzzy logic. In real life, some pedestrians would rather keep their desired speed and this is also mimicked in this paper, which is called inertia. Compared to the simple triangular membership function, a trapezoidal membership function and a piecewise linear membership function are used to capture pedestrians' inertia. With the trapezoidal and the piecewise linear membership function, many overlapping scenarios should be carefully handled and Dubois and Prade's four-index method is used to completely describe the relative relationship of fuzzy quantities. Finally, a simulation is constructed to demonstrate the effect of our model.

  13. Channel Norm-Based User Scheduling Exploiting Channel Asymmetry in Base Station Cooperative Transmission Systems

    CERN Document Server

    Han, Shengqian; Bengtsson, Mats

    2010-01-01

    Base station cooperative transmission, which is also known as coordinated multi-point (CoMP) transmission, is a promising technique to improve spectrum efficiency in future cellular systems. However, they need large signalling overhead to gather the channel information. In this paper, we consider low feedback user scheduling in downlink coherent CoMP systems exploiting their inherent channel asymmetry. Through the analysis of the statistics of the angle between channel vectors and the tightness of a lower bound of the orthogonally projected norm, we show that channel norm provides sufficient information to judge the orthogonality among users in asymmetric channels. Based on this observation, we propose a channel norm-based user scheduler (NUS), a local channel aided NUS (LocalNUS) and a large-scale fading-based user scheduler (LUS). Simulation results show that the LocalNUS performs very close to the existing greedy user scheduler (GUS) and semi-orthogonal user scheduler (SUS) with full channel state informat...

  14. Reconfigurable and Tunable Filtenna for Cognitive LTE Femtocell Base Stations

    Directory of Open Access Journals (Sweden)

    Hamza Nachouane

    2016-01-01

    Full Text Available A single-port uniplanar antenna with a built-in tunable filter is presented for operation in multiple LTE bands for cognitive femtocell applications. The antenna is based on a monopole microstrip patch fed by coplanar waveguide. The frequency reconfigurability is achieved by using two PIN diodes to couple or decouple a ring slot resonator filter from the antenna feed line. By switching the PIN diodes, the proposed design can operate in either wideband or narrowband modes. When the antenna operates in the narrowband state, two varactor diodes are used to continuously tune the narrowband frequency from 2.55 to 3.2 GHz, while the wideband state is obtained over the 1.35–6.2 GHz band. The diodes and their biasing networks have nearly no severe effect on the antenna characteristics. Prototypes of the proposed structure using ideal and real switches, with and without varactors, are fabricated and tested. Measured and simulated results are in good agreement, thus verifying the good performance of the proposed design. The obtained results show that the proposed antenna is very suitable for cognitive radio applications, in which the wideband mode is used for spectrum sensing and the narrowband mode for transmission at different frequency bands.

  15. A database based B/S design and implementation for beamline station control system

    International Nuclear Information System (INIS)

    It describes a database based B/S design and implementation for beamline station control system. The database is to establish a reasonable and effective data-sharing platform that storage the static properties of control device and the history of beamline running and also provide management and data retrieval platform of the beamline control system for engineers. (authors)

  16. 78 FR 6344 - Certain Wireless Communications Base Stations and Components Thereof Notice of Receipt of...

    Science.gov (United States)

    2013-01-30

    ...Notice is hereby given that the U.S. International Trade Commission has received a complaint entitled Certain Wireless Communications Base Stations and Components Thereof, DN 2934; the Commission is soliciting comments on any public interest issues raised by the complaint or complainant's filing under section 210.8(b) of the Commission's Rules of Practice and Procedure (19 CFR...

  17. Design of Three Phase Solar-Based 4.5kw Ac Power Inverter Station

    Directory of Open Access Journals (Sweden)

    Dr.J.C. Onuegbu

    2013-07-01

    Full Text Available The design model of a 4.50Kilowatt, 3-phase, 50 hertz solar-based power generating station was examined by the paper. The power station is a dual source input generating station using 8 series connected 100A, 12V batteries per phase as backup, the solar panels being the main frame. An inverter of 12Volt direct current input voltage was incorporated to supply an output of 3-phase, 220Volts and 50 hertz alternating current. A charging circuit was installed to monitor charging level and to preserve the accumulator’s life span. The paper also looked into the solar-based power station component design model. The batteries therein are back-up and the system will ensure 24-hours reliable power supply. The setup has a normally closed switching relay ready to pickup the auxiliary battery supply within a few milliseconds after the solar source voltage drops below a stipulated level. The three phase a.c. voltage was achieved using standby on-line circuit with cascaded 741-based flip-flop at the base of the transistor drivers of the 3-phase power transformer. This model circuit reduced the load on each phase winding and facilitated reliable and uninterruptible power supply. The delta-wyeconnected transformer will guarantee proper phase shift of 120 degrees that will emulate alternating current voltage similar to the conventional generator voltage.

  18. What input data are needed to accurately model electromagnetic fields from mobile phone base stations?

    NARCIS (Netherlands)

    Beekhuizen, Johan; Kromhout, Hans; Bürgi, Alfred; Huss, Anke; Vermeulen, Roel

    2015-01-01

    The increase in mobile communication technology has led to concern about potential health effects of radio frequency electromagnetic fields (RF-EMFs) from mobile phone base stations. Different RF-EMF prediction models have been applied to assess population exposure to RF-EMF. Our study examines what

  19. A Model for Monitoring GSM Base Station Radiation Safety in Nigeria

    Directory of Open Access Journals (Sweden)

    Dr. Godfrey Ekata

    2014-10-01

    Full Text Available A guideline for measuring the radio frequency (RF emissions from the base transceiver stations deployed by Global System Mobile Communications operators in Nigeria is proposed. The guide includes the procedures for measuring the emitted RF power and for determining whether or not the emission exceeds the maximum permissible limits in Nigeria airspace.

  20. Quality Stability of Multi-Station Assembly Process Based on Variation Stream

    Institute of Scientific and Technical Information of China (English)

    WANG Lei; GUO Wei; ZHANG Conghui; ZHAO Jiali

    2007-01-01

    To analyze the physical structure of assembly process and assure product quality, the quality stability of multi-station assembly process was investigated. First, the assembly process was modeled as a one-dimensional discrete variant system by state space equation based on variation stream. Then, the criterion to judge whether the process is stable or not and the index, stability degree, to show the level of stability were proposed by analyzing the bounded-input bounded-output(BIBO) stability of system. Finally, a simulated example of a sheet metal assembly process with three stations, was provided to verify the effectiveness of the proposed method.

  1. Research Station "Ice Base "Cape Baranov"- overview of activities in 2013 - 2015 years

    Science.gov (United States)

    Makshtas, Alexander; Sokolov, Vladimir; Bogorodskii, Peter; Kustov, Vasily; Movchan, Vadim; Laurila, Tuomas; Asmi, Eija; Popovicheva, Olga; Eleftheriadis, Kostas

    2016-04-01

    Research Station "Ice base "Cape Baranov" of Arctic and Antarctic Research Institute (AARI) had been opened in the fall 2013 on the Bolshevik Island, Archipelago Severnaya Zemlia. Now it is going as the integrated observatory, conducting comprehensive studies in practically all areas of Earth Sciences: from free atmosphere to sea ice and sea water structure in the Shokalsky Strait, from glaciers to permafrost, from paleogeography to ornithology. Overview of activities together with some preliminary results of field works at the station performing in 2014 - 2015 years by international multidisciplinary team in frame of free atmosphere, atmospheric surface layer, greenhouse gases and aerosol studies is presented together with model estimations of active soil layer.

  2. A Fuzzy Logic-Based Approach for Estimation of Dwelling Times of Panama Metro Stations

    Directory of Open Access Journals (Sweden)

    Aranzazu Berbey Alvarez

    2015-04-01

    Full Text Available Passenger flow modeling and station dwelling time estimation are significant elements for railway mass transit planning, but system operators usually have limited information to model the passenger flow. In this paper, an artificial-intelligence technique known as fuzzy logic is applied for the estimation of the elements of the origin-destination matrix and the dwelling time of stations in a railway transport system. The fuzzy inference engine used in the algorithm is based in the principle of maximum entropy. The approach considers passengers’ preferences to assign a level of congestion in each car of the train in function of the properties of the station platforms. This approach is implemented to estimate the passenger flow and dwelling times of the recently opened Line 1 of the Panama Metro. The dwelling times obtained from the simulation are compared to real measurements to validate the approach.

  3. Determination of the general public exposure around GSM and UMTS base stations

    International Nuclear Information System (INIS)

    This paper summarises two studies, in which measurement and calculation methods to determine the exposure of the general public around GSM and UMTS base stations have been developed and applied to different scenarios. The electromagnetic field variations around the stations in space and time are accounted for by appropriate maximisation techniques. Measurements show a bandwidth of exposures from 0.01% to more than 10% of field strength exposure limits. The distance to the station is not a main influencing factor, whereas the orientation to the main lobe and the sight conditions greatly influence exposure. Several commercially available numerical simulation tools were tested for their applicability on exposure forecast. In line-of-sight scenarios, all programs are able to predict the exposure accurately, whereas in non-line-of-sight situations, free space models overestimate the real exposure by some orders of magnitude. (authors)

  4. A case-based reasoning approach for estimating the costs of pump station projects

    Directory of Open Access Journals (Sweden)

    Mohamed M. Marzouk

    2011-10-01

    Full Text Available The effective estimation of costs is crucial to the success of construction projects. Cost estimates are used to evaluate, approve and/or fund projects. Organizations use some form of classification system to identify the various types of estimates that may be prepared during the lifecycle of a project. This research presents a parametric-cost model for pump station projects. Fourteen factors have been identified as important to the influence of the cost of pump station projects. A data set that consists of forty-four pump station projects (fifteen water and twenty-nine waste water are collected to build a Case-Based Reasoning (CBR library and to test its performance. The results obtained from the CBR tool are processed and adopted to improve the accuracy of the results. A numerical example is presented to demonstrate the development of the effectiveness of the tool.

  5. Association between exposure to radiofrequency electromagnetic fields assessed by dosimetry and acute symptoms in children and adolescents: a population based cross-sectional study

    Directory of Open Access Journals (Sweden)

    Radon Katja

    2010-11-01

    Full Text Available Abstract Background The increase in numbers of mobile phone users was accompanied by some concern that exposure to radiofrequency electromagnetic fields (RF EMF might adversely affect acute health especially in children and adolescents. The authors investigated this potential association using personal dosimeters. Methods A 24-hour exposure profile of 1484 children and 1508 adolescents was generated in a population-based cross-sectional study in Germany between 2006 and 2008 (participation 52%. Personal interview data on socio-demographic characteristics, self-reported exposure and potential confounders were collected. Acute symptoms were assessed twice during the study day using a symptom diary. Results Only few of the large number of investigated associations were found to be statistically significant. At noon, adolescents with a measured exposure in the highest quartile during morning hours reported a statistically significant higher intensity of headache (Odd Ratio: 1.50; 95% confidence interval: 1.03, 2.19. At bedtime, adolescents with a measured exposure in the highest quartile during afternoon hours reported a statistically significant higher intensity of irritation in the evening (4th quartile 1.79; 1.23, 2.61, while children reported a statistically significant higher intensity of concentration problems (4th quartile 1.55; 1.02, 2.33. Conclusions We observed few statistically significant results which are not consistent over the two time points. Furthermore, when the 10% of the participants with the highest exposure are taken into consideration the significant results of the main analysis could not be confirmed. Based on the pattern of these results, we assume that the few observed significant associations are not causal but rather occurred by chance.

  6. TEXSYS. [a knowledge based system for the Space Station Freedom thermal control system test-bed

    Science.gov (United States)

    Bull, John

    1990-01-01

    The Systems Autonomy Demonstration Project has recently completed a major test and evaluation of TEXSYS, a knowledge-based system (KBS) which demonstrates real-time control and FDIR for the Space Station Freedom thermal control system test-bed. TEXSYS is the largest KBS ever developed by NASA and offers a unique opportunity for the study of technical issues associated with the use of advanced KBS concepts including: model-based reasoning and diagnosis, quantitative and qualitative reasoning, integrated use of model-based and rule-based representations, temporal reasoning, and scale-up performance issues. TEXSYS represents a major achievement in advanced automation that has the potential to significantly influence Space Station Freedom's design for the thermal control system. An overview of the Systems Autonomy Demonstration Project, the thermal control system test-bed, the TEXSYS architecture, preliminary test results, and thermal domain expert feedback are presented.

  7. Improving Quality Of Service For Radio Station Hosting: An Online Recommender System Based On Information Fusion

    OpenAIRE

    Ignatov, Dmitry I.; Nikolenko, Sergey I.; Taimuraz Abaev; Jonas Poelmans

    2014-01-01

    We present a new recommender system developed for the Russian interactive radio network FMhost. The system aims to improve the quality of this service; it is designed specifically to deal with small datasets, overcoming the shortage of data on observed user behavior. The underlying model combines a collaborative user-based approach with information from tags of listened tracks in order to match user and radio station profiles. It follows an adaptive online learning strategy based on both user...

  8. Results of a cross-sectional study on the association of electromagnetic fields emitted from mobile phone base stations and health complaints; Ergebnisse einer Querschnittsstudie zum Zusammenhang von elektromagnetischen Feldern von Mobilfunksendeanlagen und unspezifischen gesundheitlichen Beschwerden

    Energy Technology Data Exchange (ETDEWEB)

    Breckenkamp, Juergen; Berg-Beckhoff, Gabriele [Bielefeld Univ. (Germany). Arbeitsgebiet Epidemiologie und International Public Health; Blettner, Maria [Mainz Univ. (Germany). Inst. fuer Medizinische Biometrie, Epidemiologie und Informatik; Kowall, Bernd [Duesseldorf Univ. (Germany). Deutsches Diabetes Zentrum; Schuez, Joachim [Institute of Cancer Epidemiology, Strandboulevarden (Denmark). Dept. of Biostatistics and Epidemiology; Schlehofer, Brigitte [Deutsches Krebsforschungszentrum Heidelberg (Germany). Arbeitsgebiet Umweltepidemiologie; Schmiedel, Sven [Mainz Univ. (Germany). Inst. fuer Medizinische Biometrie, Epidemiologie und Informatik; Institute of Cancer Epidemiology, Strandboulevarden (Denmark). Dept. of Biostatistics and Epidemiology; Bornkessel, Christian [Institut fuer Mobil- und Satellitenfunktechnik (IMST GmbH), Pruefzentrum EMV, Kamp-Lintfort (Germany); Reis, Ursula; Potthoff, Peter [TNS Healthcare GmbH, Muenchen (Germany)

    2010-07-01

    Background: Despite the fact that adverse health effects are not confirmed for exposure to radiofrequency electromagnetic field (RFEMF) levels below the limit values, as defined in the guidelines of the International Commission on Non-Ionizing Radiation Protection, many persons are worried about possible adverse health effects caused by the RF-EMF emitted from mobile phone base stations, or they attribute their unspecific health complaints like headache or sleep disturbances to these fields. Method: In the framework of a cross-sectional study a questionnaire was sent to 4150 persons living in predominantly urban areas. Participants were asked whether base stations affected their health. Health complaints were measured with standardized health questionnaires for sleep disturbances, headache, health complaints and mental and physical health. 3,526 persons responded (85%) to the questionnaire and 1,808 (51%) agreed to dosimetric measurements in their flats. Exposure was measured in 1,500 flats. Results: The measurements accomplished in the bedrooms in most cases showed very low exposure values, most often below sensitivity limit of the dosimeter. An association of exposure with the occurrence of health complaints was not found, but an association between the attribution of adverse health effects to base stations and the occurrence of health complaints. Conclusions: However, concerns about health and the attribution of adverse health effects to these mobile phone base stations should be taken serious and require a risk communication with concerned persons. Future research should focus on the processes of perception and appraisal of RF-EMF risks, and ascertain the determinants of concerns and attributions in the context of RF-EMF. (orig.)

  9. Activity-based cost analysis of hepatic tumor ablation using CT-guided high-dose rate brachytherapy or CT-guided radiofrequency ablation in hepatocellular carcinoma

    International Nuclear Information System (INIS)

    To analyse and compare the costs of hepatic tumor ablation with computed tomography (CT)-guided high-dose rate brachytherapy (CT-HDRBT) and CT-guided radiofrequency ablation (CT-RFA) as two alternative minimally invasive treatment options of hepatocellular carcinoma (HCC). An activity based process model was created determining working steps and required staff of CT-RFA and CT-HDRBT. Prorated costs of equipment use (purchase, depreciation, and maintenance), costs of staff, and expenditure for disposables were identified in a sample of 20 patients (10 treated by CT-RFA and 10 by CT-HDRBT) and compared. A sensitivity and break even analysis was performed to analyse the dependence of costs on the number of patients treated annually with both methods. Costs of CT-RFA were nearly stable with mean overall costs of approximately 1909 €, 1847 €, 1816 € and 1801 € per patient when treating 25, 50, 100 or 200 patients annually, as the main factor influencing the costs of this procedure was the single-use RFA probe. Mean costs of CT-HDRBT decreased significantly per patient ablation with a rising number of patients treated annually, with prorated costs of 3442 €, 1962 €, 1222 € and 852 € when treating 25, 50, 100 or 200 patients, due to low costs of single-use disposables compared to high annual fix-costs which proportionally decreased per patient with a higher number of patients treated annually. A break-even between both methods was reached when treating at least 55 patients annually. Although CT-HDRBT is a more complex procedure with more staff involved, it can be performed at lower costs per patient from the perspective of the medical provider when treating more than 55 patients compared to CT-RFA, mainly due to lower costs for disposables and a decreasing percentage of fixed costs with an increasing number of treatments

  10. Radiofrequency attenuator and method

    Science.gov (United States)

    Warner, Benjamin P.; McCleskey, T. Mark; Burrell, Anthony K.; Agrawal, Anoop; Hall, Simon B.

    2009-11-10

    Radiofrequency attenuator and method. The attenuator includes a pair of transparent windows. A chamber between the windows is filled with molten salt. Preferred molten salts include quarternary ammonium cations and fluorine-containing anions such as tetrafluoroborate (BF.sub.4.sup.-), hexafluorophosphate (PF.sub.6.sup.-), hexafluoroarsenate (AsF.sub.6.sup.-), trifluoromethylsulfonate (CF.sub.3SO.sub.3.sup.-), bis(trifluoromethylsulfonyl)imide ((CF.sub.3SO.sub.2).sub.2N.sup.-), bis(perfluoroethylsulfonyl)imide ((CF.sub.3CF.sub.2SO.sub.2).sub.2N.sup.-) and tris(trifluoromethylsulfonyl)methide ((CF.sub.3SO.sub.2).sub.3 C.sup.-). Radicals or radical cations may be added to or electrochemically generated in the molten salt to enhance the RF attenuation.

  11. New classification scheme for ozone monitoring stations based on frequency distribution of hourly data.

    Science.gov (United States)

    Tapia, O; Escudero, M; Lozano, Á; Anzano, J; Mantilla, E

    2016-02-15

    According to European Union (EU) legislation, ozone (O3) monitoring sites can be classified regarding their location (rural background, rural, suburban, urban) or based on the presence of emission sources (background, traffic, industrial). There have been attempts to improve these classifications aiming to reduce their ambiguity and subjectivity, but although scientifically sound, they lack the simplicity needed for operational purposes. We present a simple methodology for classifying O3 stations based on the characteristics of frequency distribution curves which are indicative of the actual impact of combustion sources emitting NO that consumes O3 via titration. Four classes are identified using 1998-2012 hourly data from 72 stations widely distributed in mainland Spain and the Balearic Islands. Types 1 and 2 present unimodal bell-shaped distribution with very low amount of data near zero reflecting a limited influence of combustion sources while Type 4 has a primary mode close to zero, showing the impact of combustion sources, and a minor mode for higher concentrations. Type 3 stations present bimodal distributions with the main mode in the higher levels. We propose a quantitative metric based on the Gini index with the objective of reproducing this classification and finding empirical ranges potentially useful for future classifications. The analysis of the correspondence with the EUROAIRNET classes for the 72 stations reveals that the proposed scheme is only dependent on the impact of combustion sources and not on climatic or orographic aspects. It is demonstrated that this classification is robust since in 87% of the occasions the classification obtained for individual years coincide with the global classification obtained for the 1998-2012 period. Finally, case studies showing the applicability of the new classification scheme for assessing the impact on O3 of a station relocation and performing a critical evaluation of an air quality monitoring network are

  12. Optimal Base Station Placement: A Stochastic Method Using Interference Gradient In Downlink Case

    CERN Document Server

    Malik, Salman; Kelif, Jean-Marc

    2011-01-01

    In this paper, we study the optimal placement and optimal number of base stations added to an existing wireless data network through the interference gradient method. This proposed method considers a sub-region of the existing wireless data network, hereafter called region of interest. In this region, the provider wants to increase the network coverage and the users throughput. In this aim, the provider needs to determine the optimal number of base stations to be added and their optimal placement. The proposed approach is based on the Delaunay triangulation of the region of interest and the gradient descent method in each triangle to compute the minimum interference locations. We quantify the increase of coverage and throughput.

  13. Radiofrequency Ablation of Lung Tumors

    Science.gov (United States)

    ... a specially trained interventional radiologist in an interventional radiology suite or occasionally in the operating room. Radiofrequency ... page Additional Information and Resources Society of Interventional Radiology (SIR) - Patient Section top of page This page ...

  14. Frequency control of radiofrequency cavity

    OpenAIRE

    Menart, Jure

    2014-01-01

    This work describes the design, development and application of the system for frequency control of EMMA accelerator radiofrequency cavity. The problem with the radiofrequency cavities is, that because of various factors (change in the environmental temperature, mechanical stress, ...), they are continuously frequency detuning. The consequence of the frequency detuning is that electromagnetic field in the cavity is not optimal for the acceleration of the particles. For this reason the resonant...

  15. The radio-frequency quadrupole

    OpenAIRE

    Vretenar, Maurizio

    2013-01-01

    Radio-frequency quadrupole (RFQ) linear accelerators appeared on the accelerator scene in the late 1970s and have since revolutionized the domain of low-energy proton and ion acceleration. The RFQ makes the reliable production of unprecedented ion beam intensities possible within a compact radio-frequency (RF) resonator which concentrates the three main functions of the low-energy linac section: focusing, bunching and accelerating. Its sophisticated electrode structure and strict beam dynamic...

  16. Lambda Station: On-demand flow based routing for data intensive Grid applications over multitopology networks

    Energy Technology Data Exchange (ETDEWEB)

    Bobyshev, A.; Crawford, M.; DeMar, P.; Grigaliunas, V.; Grigoriev, M.; Moibenko, A.; Petravick, D.; Rechenmacher, R.; /Fermilab; Newman, H.; Bunn, J.; Van Lingen, F.; Nae,; Ravot, S.; Steenberg, C.; Su, X.; Thomas, M.; Xia, Y.; /Caltech

    2006-08-01

    Lambda Station is an ongoing project of Fermi National Accelerator Laboratory and the California Institute of Technology. The goal of this project is to design, develop and deploy network services for path selection, admission control and flow based forwarding of traffic among data-intensive Grid applications such as are used in High Energy Physics and other communities. Lambda Station deals with the last-mile problem in local area networks, connecting production clusters through a rich array of wide area networks. Selective forwarding of traffic is controlled dynamically at the demand of applications. This paper introduces the motivation of this project, design principles and current status. Integration of Lambda Station client API with the essential Grid middleware such as the dCache/SRM Storage Resource Manager is also described. Finally, the results of applying Lambda Station services to development and production clusters at Fermilab and Caltech over advanced networks such as DOE's UltraScience Net and NSF's UltraLight is covered.

  17. Analyzing mobile WiMAX base station deployment under different frequency planning strategies

    Science.gov (United States)

    Salman, M. K.; Ahmad, R. B.; Ali, Ziad G.; Aldhaibani, Jaafar A.; Fayadh, Rashid A.

    2015-05-01

    The frequency spectrum is a precious resource and scarce in the communication markets. Therefore, different techniques are adopted to utilize the available spectrum in deploying WiMAX base stations (BS) in cellular networks. In this paper several types of frequency planning techniques are illustrated, and a comprehensive comparative study between conventional frequency reuse of 1 (FR of 1) and fractional frequency reuse (FFR) is presented. These techniques are widely used in network deployment, because they employ universal frequency (using all the available bandwidth) in their base station installation/configuration within network system. This paper presents a network model of 19 base stations in order to be employed in the comparison of the aforesaid frequency planning techniques. Users are randomly distributed within base stations, users' resource mapping and their burst profile selection are based on the measured signal to interference plus-noise ratio (SINR). Simulation results reveal that the FFR has advantages over the conventional FR of 1 in various metrics. 98 % of downlink resources (slots) are exploited when FFR is applied, whilst it is 81 % at FR of 1. Data rate of FFR has been increased to 10.6 Mbps, while it is 7.98 Mbps at FR of 1. The spectral efficiency is better enhanced (1.072 bps/Hz) at FR of 1 than FFR (0.808 bps/Hz), since FR of 1 exploits all the Bandwidth. The subcarrier efficiency shows how many data bits that can be carried by subcarriers under different frequency planning techniques, the system can carry more data bits under FFR (2.40 bit/subcarrier) than FR of 1 (1.998 bit/subcarrier). This study confirms that FFR can perform better than conventional frequency planning (FR of 1) which made it a strong candidate for WiMAX BS deployment in cellular networks.

  18. Autonomous portable pulsed-periodical generator of high-power radiofrequency-pulses based on gas discharge with hollow cathode

    Science.gov (United States)

    Bulychev, Sergey V.; Dubinov, Alexander E.; L'vov, Igor L.; Popolev, Vyacheslav L.; Sadovoy, Sergey A.; Sadchikov, Eugeny A.; Selemir, Victor D.; Valiulina, Valeria K.; Vyalykh, Dmitry V.; Zhdanov, Victor S.

    2016-05-01

    Portable autonomous generator of high-power RF-pulses based on the gas discharge with hollow cathode has been designed, fabricated, and tested. Input and output characteristics are the following: discharge current amplitude is 800 A, duration of generated RF-pulses is 350 ns, carrier frequency is ˜90 MHz, power in RF-pulse is 0.5 MW, pulse repetition rate is 0.5 kHz, and device efficiency is ˜25%.

  19. Exposure to radiation from base stations of mobile communication systems on top of buildings

    International Nuclear Information System (INIS)

    This paper discusses the problems related with the safety of people exposed to radiation coming from base stations of mobile communication systems installed on the top of buildings in urban environments. After introducing the problem, the approach taken in the paper is presented: the issue is not to know if exposure to radiation is hazardous but to know what are the exposure limits that may constitute danger. Afterwards, the maximum values recommended by several international bodies are shown for the specific absorption range in the frequency range of mobile communications and, in particular, for GSM. Measurements done in a building in Lisbon, Portugal, with antennas on its top show that the signal is circa 50,000 times below the maximum values, hence perfectly within the safety margins. One can say that, in the large majority of cases, there is no danger for people working or living in buildings with base station antennas installed on their top (author)

  20. A Potential Transmitter Architecture for Future Generation Green Wireless Base Station

    Directory of Open Access Journals (Sweden)

    Mike Faulkner

    2009-01-01

    Full Text Available Current radio frequency power amplifiers in 3G base stations have very high power consumption leading to a hefty cost and negative environmental impact. In this paper, we propose a potential architecture design for future wireless base station. Issues associated with components of the architecture are investigated. The all-digital transmitter architecture uses a combination of envelope elimination and restoration (EER and pulse width modulation (PWM/pulse position modulation (PPM modulation. The performance of this architecture is predicted from the measured output power and efficiency curves of a GaN amplifier. 57% efficiency is obtained for an OFDM signal limited to 8 dB peak to average power ratio. The PWM/PPM drive signal is generated using the improved Cartesian sigma delta techniques. It is shown that an RF oversampling by a factor of four meets the WLAN spectral mask, and WCDMA specification is met by an RF oversampling of sixteen.

  1. Mechanism Design for Base Station Association and Resource Allocation in Downlink OFDMA Network

    CERN Document Server

    Hong, Mingyi

    2012-01-01

    We consider a resource management problem in a multi-cell downlink OFDMA network, whereby the goal is to find the optimal per base station resource allocation and user-base station assignment. The users are assumed to be strategic/selfish who have private information on downlink channel states and noise levels. To induce truthfulness among the users as well as to enhance the spectrum efficiency, the resource management strategy needs to be both incentive compatible and efficient. However, due to the mixed (discrete and continuous) nature of resource management in this context, the implementation of any incentive compatible mechanism that maximizes the system throughput is NP-hard. We consider the dominant strategy implementation of an approximately optimal resource management scheme via a computationally tractable mechanism. The proposed mechanism is decentralized and dynamic. More importantly, it ensures the truthfulness of the users and it implements a resource allocation solution that yields at least 1/2 o...

  2. Investigation of the exposure level of electromagnetic fields produced by mobile telephone base stations

    International Nuclear Information System (INIS)

    The electromagnetic field levels in the surrounding of different samples of mobile phone base station were investigated in order to cover residential zones of Damascus and her environs. Measurements were achieved according to the emission direction and to the studied positions environment. Results showed that the signal level in all measured points is lower than the International Commission on Non Ionizing Radiation Protection (ICNIRP) restriction level, but for few measurement points the detected microwave level has relatively important values. The signal level inside building situated partially in the emission direction of the base station transmitters decreases stepwise and walls reduce considerably the signal intensity. This study showed the importance of achieving a transparent collaboration between research laboratory and mobile phone companies in order to improve the protection level.(author)

  3. A cryogenic front end for CDMA and UMTS wireless base stations

    International Nuclear Information System (INIS)

    The design and the laboratory performance of a cryogenic front end for CDMA and UMTS wireless base stations is described together with the results of a first field test at a CDMA base station in the region of Tangshan in China. The central elements of the cryogenic front ends are the cryocooler, the cryostat and the cryogenic platform mounted with up to 6 HTS pre-selection filters of high selectivity combined with the corresponding cryogenic low noise amplifiers of high dynamic range as well as the associated control electronics. Design and performance of the UMTS and CDMA filters are described and the characteristic parameters of the cryogenic low noise preamplifier are given. An analysis of the results of the first field test is discussed

  4. Implicit attitudes toward nuclear power and mobile phone base stations: support for the affect heuristic.

    Science.gov (United States)

    Siegrist, Michael; Keller, Carmen; Cousin, Marie-Eve

    2006-08-01

    The implicit association test (IAT) measures automatic associations. In the present research, the IAT was adapted to measure implicit attitudes toward technological hazards. In Study 1, implicit and explicit attitudes toward nuclear power were examined. Implicit measures (i.e., the IAT) revealed negative attitudes toward nuclear power that were not detected by explicit measures (i.e., a questionnaire). In Study 2, implicit attitudes toward EMF (electro-magnetic field) hazards were examined. Results showed that cell phone base stations and power lines are judged to be similarly risky and, further, that base stations are more closely related to risk concepts than home appliances are. No differences between experts and lay people were observed. Results of the present studies are in line with the affect heuristic proposed by Slovic and colleagues. Affect seems to be an important factor in risk perception. PMID:16948694

  5. Design of Radio Frequency Link in Automatic Test System for Multimode Mobile Communication Base Station

    Science.gov (United States)

    Zhang, Weipeng

    2015-12-01

    A modularized design for the radio frequency (RF) link in automatic test system of multimode mobile communication base station is presented, considering also the characteristics of wireless communication indices and composition of signals of base stations. The test link is divided into general module, time division duplex (TDD) module, module of spurious noise filter, module of downlink intermodulation, module of uplink intermodulation and uplink block module. The composition of modules and link functions are defined, and the interfaces of the general module and the module of spurious noise filter are described. Finally, the estimated gain budget of the test link is presented. It is verified by experiments that the system is reliable and the test efficiency is improved.

  6. The vertical pattern of microwave radiation around BTS (Base Transceiver Station) antennae in Hashtgerd township

    OpenAIRE

    Nasseri, Simin; Monazzam, Mohammadreza; Beheshti, Meisam; Zare, Sajad; Mahvi, Amirhosein

    2013-01-01

    New environmental pollutants interfere with the environment and human life along with technology development. One of these pollutants is electromagnetic field. This study determines the vertical microwave radiation pattern of different types of Base Transceiver Station (BTS) antennae in the Hashtgerd city as the capital of Savojbolagh County, Alborz Province of Iran. The basic data including the geographical location of the BTS antennae in the city, brand, operator type, installation and its ...

  7. A pressure control method for emulsion pump station based on Elman neural network.

    Science.gov (United States)

    Tan, Chao; Qi, Nan; Zhou, Xin; Liu, Xinhua; Yao, Xingang; Wang, Zhongbin; Si, Lei

    2015-01-01

    In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was feasible and efficient and outperformed others. PMID:25861253

  8. A Pressure Control Method for Emulsion Pump Station Based on Elman Neural Network

    OpenAIRE

    2015-01-01

    In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was...

  9. Attitude Estimation for In-Service Base Station Antenna Using Downlink Channel Fading Statistics

    OpenAIRE

    2015-01-01

    A maximum-likelihood-estimation method is proposed for extracting the attitude of a sectoring base station (BS) antenna by using the received signal strengths observed by multiple user equipments (UEs) in this contribution. This method calculates the likelihood function of the antenna attitude derived by taking into account the multiscale fading statistics, that is, path loss, shadowing, and multipath fading. Depending on whether a calibration result of these fading statistics is available or...

  10. InfoStation-based Adaptable Provision of m Learning Services: Main Scenarios

    OpenAIRE

    Ganchev, Ivan; Stojanov, Stanimir; O’Droma, Mairtin; Meere, Damien

    2008-01-01

    This paper presents an adaptable InfoStation-based multi-agent system facilitating the mobile eLearning (mLearning) service provision within a University Campus. A horizontal view of the network architecture is presented. Main communications scenarios are considered by describing the detailed interaction of the system entities involved in the mLearning service provision. The mTest service is explored as a practical example. System implementation approaches are also considered.

  11. Joint QoS Multicast Power / Admission Control and Base Station Assignment : A Geometric Programming Approach

    OpenAIRE

    Karipidis, Eleftherios; Sidiropoulos, Nicholas; Tassiulas, Leandros

    2008-01-01

    The joint power control and base station (BS) assignment problem is considered under Quality-of-Service (QoS) constraints. If a feasible solution exists, the problem can be efficiently solved using existing distributed algorithms. Infeasibility is often encountered in practice, however, which brings up the issue of optimal admission control. The joint problem is NP-hard, yet important for QoS provisioning and bandwidth-efficient operation of existing and emerging cellular and overlay/underlay...

  12. Human exposition to non ionizing electromagnetic radiations. Legislation and base stations measurements

    Directory of Open Access Journals (Sweden)

    Alonso Alonso Alonso

    2004-12-01

    Full Text Available This work deals about measurement procedures of non-ionizing radiations and their recorded levels in practice. The analyzed radiation sources cover the most common broadcasting media such as AM and FM transmissions and the GSM mobile telephony base stations. These sources currently radiate locations with high density of population. Spanish radiation level regulations are briefly described and some possible improvements are pointed out. The measurement results are discussed.

  13. Modeling the Interference Generated from Car Base Stations towards Indoor Femto-cells

    OpenAIRE

    Cho, Byungjin; Koufos, Konstantinos; Ruttik, Kalle; Jäntti, Riku

    2015-01-01

    In future wireless networks, a significant number of users will be vehicular. One promising solution to improve the capacity for these vehicular users is to employ moving relays or car base stations. The system forms cell inside the vehicle and then uses rooftop antenna for back-hauling to overcome the vehicular penetration loss. In this paper, we develop a model for aggregate interference distribution generated from moving/parked cars to indoor users in order to study whether indoor femto-ce...

  14. PV-solar / wind hybrid energy system for GSM/CDMA type mobile telephony base station

    Energy Technology Data Exchange (ETDEWEB)

    Nema, Pragya; Rangnekar, Saroj [Energy Engineering Department, Maulana Azad National Institute of Technology , Bhopal-462007 M.P. (India); Nema, R.K. [Electrical Engineering Department, Maulana Azad National Institute of Technology, Bhopal-462007 M.P. (India)

    2010-07-01

    This paper gives the design idea of optimized PV-Solar and Wind Hybrid Energy System for GSM/CDMA type mobile base station over conventional diesel generator for a particular site in central India (Bhopal). For this hybrid system ,the meteorological data of Solar Insolation, hourly wind speed, are taken for Bhopal-Central India (Longitude 77 deg.23'and Latitude 23 deg.21' ) and the pattern of load consumption of mobile base station are studied and suitably modeled for optimization of the hybrid energy system using HOMER software. The simulation and optimization result gives the best optimized sizing of wind turbine and solar array with diesel generator for particular GSM/CDMA type mobile telephony base station. This system is more cost effective and environmental friendly over the conventional diesel generator. It should reduced approximate 70%-80% fuel cost over conventional diesel generator and also reduced the emission of CO2 and other harmful gasses in environments. It is expected that the newly developed and installed system will provide very good opportunities for telecom sector in near future.

  15. The Mediterranean Oscillation Teleconnection Index: Station-Based versus Principal Component Paradigms

    Directory of Open Access Journals (Sweden)

    Francisco Criado-Aldeanueva

    2013-01-01

    Full Text Available Two different paradigms of the Mediterranean Oscillation (MO teleconnection index have been compared in this work: station-based definitions obtained by the difference of some climate variable between two selected points in the eastern and western basins (i.e., Algiers and Cairo, Gibraltar and Israel, Marseille and Jerusalem, or south France and Levantine basin and the principal component (PC approach in which the index is obtained as the time series of the first mode of normalised sea level pressure anomalies across the extended Mediterranean region. Interannual to interdecadal precipitation (P, evaporation (E, E-P, and net heat flux have been correlated with the different MO indices to compare their relative importance in the long-term variability of heat and freshwater budgets over the Mediterranean Sea. On an annual basis, the PC paradigm is the most effective tool to assess the effect of the large-scale atmospheric forcing in the Mediterranean Sea because the station-based indices exhibit a very poor correlation with all climatic variables and only influence a reduced fraction of the basin. In winter, the station-based indices highly improve their ability to represent the atmospheric forcing and results are fairly independent of the paradigm used.

  16. PV-solar / wind hybrid energy system for GSM/CDMA type mobile telephony base station

    Directory of Open Access Journals (Sweden)

    Pragya Nema, R.K. Nema, Saroj Rangnekar

    2010-03-01

    Full Text Available This paper gives the design idea of optimized PV-Solar and Wind Hybrid Energy System for GSM/CDMA type mobile base station over conventional diesel generator for a particular site in central India (Bhopal . For this hybrid system ,the meteorological data of Solar Insolation, hourly wind speed, are taken for Bhopal-Central India (Longitude 77o.23'and Latitude 23o.21' and the pattern of load consumption of mobile base station are studied and suitably modeled for optimization of the hybrid energy system using HOMER software. The simulation and optimization result gives the best optimized sizing of wind turbine and solar array with diesel generator for particular GSM/CDMA type mobile telephony base station. This system is more cost effective and environmental friendly over the conventional diesel generator. It should reduced approximate 70%-80% fuel cost over conventional diesel generator and also reduced the emission of CO2 and other harmful gasses in environments. It is expected that the newly developed and installed system will provide very good opportunities for telecom sector in near future.

  17. Magnetic Base Station Deceptions, a magnetovariational analysis along the Ligurian Sea coast, Italy

    Directory of Open Access Journals (Sweden)

    E. Bozzo

    2007-06-01

    Full Text Available Reliability of high resolution airborne and shipborne magnetic surveys depends on accurate removal of temporal variations from the recorded total magnetic field intensity data. At mid latitudes, one or a few base stations are typically located within or near the survey area and are used to monitor and remove time dependent variations. These are usually assumed to be of external origin and uniform throughout the survey area. Here we investigate the influence on the magnetic base station correction of the time varying magnetic field variations generated by internal telluric currents flowing in anomalous regional 2D/3D conductivity structures. The study is based on the statistical analysis of a data set collected by four magnetovariational stations installed in northwestern Italy. The variometer stations were evenly placed with a spacing of about 60 km along a profile roughly parallel to the coastline. They recorded the geomagnetic field from the beginning to the end of April 2005, with a sampling rate of 0.33 Hz. Cross-correlation and coherence analysis applied to a subset of 125 five hours long magnetic events indicates that, for periods longer than 400 s, there is an high correlation between the horizontal magnetic field components at the different stations. This indicates spatial uniformity of the source field and of the induced currents in the 1D Earth. Additionally, the pattern of the induction arrows, estimated from single site transfer functions, reveals a clear electromagnetic signature of the Sestri-Voltaggio line, interpreted as a major regional tectonic boundary. Induced telluric currents flowing through this 2D/3D electrical conductivity discontinuity affect mainly the vertical magnetic component at the closer locations. By comparing this component at near (32 km and far (70 km stations, we have found that the mean value of the power spectra ratio, due to the electromagnetic induced field, is about 1.8 in the frequency

  18. Spin exchange optical pumping based polarized 3He filling station for the Hybrid Spectrometer at the Spallation Neutron Source

    International Nuclear Information System (INIS)

    The Hybrid Spectrometer (HYSPEC) is a new direct geometry spectrometer at the Spallation Neutron Source at the Oak Ridge National Laboratory. This instrument is equipped with polarization analysis capability with 60° horizontal and 15° vertical detector coverages. In order to provide wide angle polarization analysis for this instrument, we have designed and built a novel polarized 3He filling station based on the spin exchange optical pumping method. It is designed to supply polarized 3He gas to HYSPEC as a neutron polarization analyzer. In addition, the station can optimize the 3He pressure with respect to the scattered neutron energies. The depolarized 3He gas in the analyzer can be transferred back to the station to be repolarized. We have constructed the prototype filling station. Preliminary tests have been carried out demonstrating the feasibility of the filling station. Here, we report on the design, construction, and the preliminary results of the prototype filling station.

  19. 75 FR 68353 - Pilgrim Stage Station Wind Park, LLC; Supplemental Notice That Initial Market-Based Rate Filing...

    Science.gov (United States)

    2010-11-05

    ... Energy Regulatory Commission Pilgrim Stage Station Wind Park, LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes Request for Blanket Section 204 Authorization October 28, 2010. This is a supplemental notice in the above-referenced proceeding of Pilgrim Stage Station Wind Park,...

  20. Stability of the CBM CA based track finder with respect to number of stations

    International Nuclear Information System (INIS)

    The main tracking detector in the CBM experiment (FAIR, Darmstadt, Germany) is the Silicon Tracking System (STS). %It is placed in dipole magnet and designed to give momentum resolution about 1%. A number of conditions complicates the track reconstruction in STS: up to 1000 tracks per event, up to 107 events per second, non-homogeneous magnetic field, up to 85% fake combinatorial space points in double-sided strip detectors. The cellular automaton (CA) based track reconstruction performs with efficiency of 98% and time of 12 ms with standard STS setup, consisting of 8 stations. The detector is placed in a dipole magnet and the space available for STS is limited. Therefore geometries with different number of stations required to be considered additionally. Tests of the CA based reconstruction have been performed with data simulated in 7 different STS setups, changing number of STS stations from 4 to 8. %Tests with simulated central and minimum bias Au+Au collisions at 25 AGeV have been performed. The track reconstruction efficiencies for majority of the signal tracks stays on the level of 90-100% for all setups for minimum bias events. Momentum resolution stays on the same level of 1.3% for all STS setups, which has at least 70 cm length.

  1. Measurement of radiofrequency fields

    International Nuclear Information System (INIS)

    We are literally surrounded by radiofrequency (RFR) and microwave radiation, from both natural and man-made sources. The identification and control of man-made sources of RFR has become a high priority of radiation safety professionals in recent years. For the purposes of this paper, we will consider RFR to cover the frequencies from 3 kHz to 300 MHz, and microwaves from 300 MHz to 300 GHz, and will use the term RFR interchangeably to describe both. Electromagnetic radiation and field below 3 kHz is considered Extremely Low Frequency (ELF) and will not be discussed in this paper. Unlike x- and gamma radiation, RFR is non-ionizing. The energy of any RFR photon is insufficient to produce ionizations in matter. The measurement and control of RFR hazards is therefore fundamentally different from ionizing radiation. The purpose of this paper is to acquaint the reader with the fundamental issues involved in measuring and safely using RFR fields. 23 refs

  2. Flywheel-Based Distributed Bus Signalling Strategy for the Public Fast Charging Station

    DEFF Research Database (Denmark)

    Dragicevic, Tomislav; Sucic, Stepjan; Vasquez, Juan Carlos;

    2014-01-01

    Fast charging stations (FCS) are able to recharge plug-in hybrid electric vehicles (pHEVs) in less than half an hour, thus representing an appealing concept to vehicle owners since the off-road time is similar as for refuelling at conventional public gas stations. However, since these FCS plugs...... have power ratings of up to 100 kW, they may expose the utility mains to intolerable stresses in the near future scenario where there will be a large number of public FCS spread across the network. This paper proposes an internal power balancing strategy for FCS based on flywheel energy storage system...... layer affect the stability features of the system, a reduced order small-signal model has been assembled and parameters have been selected accordingly. Finally, real-time simulation results performed on a full scale model have been reported in order to verify the validity of proposed approach....

  3. Heat flows and energetic behavior of a telecommunication radio base station

    CERN Document Server

    Petraglia, Antonio; Vetromile, Carmela; D'Onofrio, Antonio; Lubritto, Carmine

    2015-01-01

    This paper shows a study on energetic consumption of BTSs (Base Transceiver Stations) for mobile communication, related to conditioning functions. An energetic "thermal model" of a telecommunication station is proposed and studied. The results have been validated with a BTS in central Italy, showing good agreement. Findings show a substantial high internal-external temperature difference in the containing shelter, particularly during daytime and warm months, due to sources of heat (equipment, external temperature and sun radiation) and to the difficulty in spread the warmth out. The necessity to keep the operating temperatures within a given range for the correct functioning of the electronic equipment requires the use of conditioning setups, and this significantly increases the energetic demand of the whole system. The analysis of thermal flows across the shelter can help to gather further data on its temperature behavior and to devise practical measures to lower the power demand, while keeping the operating...

  4. Self-Oscillating Soft Switching Envelope Tracking Power Supply for Tetra2 Base Station

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

    2007-01-01

    This paper presents a high-efficiency, high-bandwidth solution to implementing an envelope tracking power supply for the RF power amplifier (RFPA) in a Tetra2 base station. The solution is based on synchronous rectified buck topology, augmented with high-side switch zero-current switching (ZCS......) implemented with a series inductor and an external clamping power supply. Combined with advanced power stage components (die-size MOSFETs), a high-performance fixed-frequency self-oscillating (sliding mode) control strategy and a 4th-order output filter, this leads to a compact, effective and efficient...

  5. TEDS Base Station Power Amplifier using Low-Noise Envelope Tracking Power Supply

    DEFF Research Database (Denmark)

    Høyerby, Mikkel Christian Wendelboe; Andersen, Michael A. E.

    2009-01-01

    This paper demonstrates a highly linear and efficient TETRA enhanced data service (TEDS) base-station RF power amplifier (RFPA). Based on the well-known combination of an envelope tracking (ET) power supply and a linear class-A/B RFPA, adequate adjacent channel power ratio (ACPR) and wideband noise...... performance is shown to be enabled only by further incorporating high-bandwidth Cartesian feedback (CFB) and using a low-noise ET power supply. It is demonstrated that CFB loop bandwidth is limited by modulator/demodulator/RF path group delay to around 2 MHz in the considered setup, and that there exists a...

  6. PID Controller Parameters Tuning Based-on Satisfaction for Superheated Steam Temperature of Power Station Boiler

    Directory of Open Access Journals (Sweden)

    Benxian Xiao

    2014-06-01

    Full Text Available Proposed the PID controller parameters tuning method based-on New Luus-Jaakola (NLJ algorithm and satisfaction idea. According to the different requirements of each performance index, designed the satisfaction function with fuzzy constraint attributes, and then determined the comprehensive satisfaction function for PID tuning by NLJ algorithm. Provided the steps of PID controller parameters tuning based on the NLJ algorithm and satisfaction, and applied this tuning method to the cascade control system of superheated steam temperature for Power Station Boiler. Finally the simulation and experiment results have shown the proposed method has good dynamic and static control performances for this complicated superheated steam temperature control system.

  7. Endoscopic ultrasound guided radiofrequency ablation in pancreas

    DEFF Research Database (Denmark)

    Seicean, Andrada; Tefas, Cristian; Ungureanu, Bogdan;

    2014-01-01

    Radiofrequency ablation of the pancreas represents a more effective tumor-destruction method compared to other ablation techniques. The endoscopic ultrasound guided radiofrequency ablation is indicated for locally advanced, non-metastatic pancreatic adenocarcinoma, without the need of general...

  8. RADIOFREQUENCY AND MICROWAVE RADIATION HEALTH EFFECTS AND OCCUPATIONAL EXPOSURE

    Directory of Open Access Journals (Sweden)

    Ivana Damnjanović

    2011-12-01

    Full Text Available In the recent years, there have been considerable discussion and concern about the possible hazards of RF/MW radiation. More recently, the growth and development in personal mobile communications have focused attention on the frequencies associated with this technology. A number of studies have examined the health effects of RF/MW electromagnetic fields (EMFs, originating from occupational exposure, hobbies, or residence near the radio or television transmitters. Particularly controversial are the biophysical mechanisms by which these RF fields may affect biological systems. General health effects reviews explore possible carcinogenic, reproductive and neurological effects. Health effects by exposure source have been observed in radar traffic devices, wireless communications with cellular phones, radio transmission, and magnetic resonance imaging (MRI. Several epidemiological surveys have suggested associations with non-specific complaints such as headache, tiredness, sleep disturbance, loss of memory, and dizziness. These findings, which echo reports of illness associated with other types of radiofrequency (RF radiation, relate not only to the use of mobile phones, but also to residence near the mobile phone base stations and other settings involving occupational exposure. The biological effects suggest that some precautions are necessary, and preventive approaches are highly recommended. Further researches are required to give more information about the effects of microwave radiation on our health, especially in occupational setting and professionally exposed workers.

  9. Diagnosis of Multiple Fixture Faults in Multiple-Station Manufacturing Processes Based on State Space Approach

    Institute of Scientific and Technical Information of China (English)

    田兆青; 来新民; 林忠钦

    2004-01-01

    Dimensional quality is one of the most critical challenges in industries, which uses the multistage manufacturing process (MMP) such as assembly and machining for automotive and aerospace industries. According to investigations, fixture faults accounted for 72% of all the dimensional faults. Previous studies focused on only one fault or multiple faults occurred in one station or one fault in multiple stations, but these cases rarely appear in the real manufacturing. This paper presents a method for diagnosis of multiple fixture faults in the multi-station manufacturing process. The proposed method is based on the state space model of the MMP processes, which carries the information of the fixture layout geometry and sensor position. To identify the root cause, three continuous steps were used: a) development of the state space model and the construction of the statistics variables on offline mode, b) measurement of the coordinate measuring machines data on online mode and calculation of the statistics variables, and c) diagnostic algorithm for identifying the root cause. The presented paper integrates the state space model of the manufacturing processes and hypothesis test considering the impact of the measure noises. A case study verifies the proposed method.

  10. The Development of Calder Hall and Chapelcross as Base Load Nuclear Power Stations

    International Nuclear Information System (INIS)

    The initial design conception of Calder Hall and Chapelcross was as dual-purpose power reactors with the major emphasis on production of plutonium for military purposes. During the design stage optimization was carried out to enable the best possible results to be achieved from the electricity generation point of view. Both stations are integral parts of the National Electricity Grid supply system as base-load power stations and supply about 15% of the demand in the regions in which they are located. Their performance in this capacity has been developed considerably during the seven years that have elapsed since Calder Hall was officially opened in 1956. The power output of the reactors has been increased by over one-third above the initial design figure. This has been largely achieved by careful research into the methods of temperature assessment of the fuel elements and the use of control rods as movable absorbers to supplement the fixed absorbers used for flux shaping. The criterion on which temperature control is based has been developed over the years in order to allow the maximum output to be obtained while still retaining very adequate safety margins. One result of this has been that the turbo*alternator sets have been modified to increase their outputs from the original design figure of 21 MW(e) to 27/30 MW(e) in order to cope with the extra steam. Calder Hall and Chapelcross reactors are now achieving overall load factors in excess of 92% in spite of the fact that refuelling is carried out off-load. Increases in load factor have been largely achieved by marked reductions in the time taken up by refuelling and by careful planning of essential maintenance work which involves shutting down reactors. In this respect gains have been made by the application of method study and critical path techniques. Losses due to failed fuel elements have been very small. In addition to the operation of the Station for electricity generation, a large number of special

  11. Evaluation Of Geo-Spatial Proximity Of Mobile Communication GSM Base Transceiver Stations To Buildings In Ile-Ife Nigeria

    OpenAIRE

    Badru; R. van der A; Alwadood; J.A.van; Atijosan; A.O.,; Oloko-Oba; Van, M.A.; Babalogbon; B.A.; Jesuleye; I. .. A.; Alaga; , T. A.; Shaba H.A.

    2015-01-01

    Efficient placement of radio facilities for the communication base transceiver station CBS of the two small global system for mobile communication GSM has being an area of research due to fast growing of GSM market in Nigeria. In line with this development Nigerian Communication Commission NCC and Nigeria Environmental Standard and Regulation Enforcement Agency NESREA have stated the setback between communication base station and the nearest infrastructure as 5 m and 10 m respectively. To eva...

  12. SURVEI TOPOGRAFI UNTUK MENENTUKAN GARIS TAMPAK PANDANG BASE TRANSCEIVER STATION (BTS

    Directory of Open Access Journals (Sweden)

    Arief Laila Nugraha

    2012-02-01

    Full Text Available Base Transceiver Station (BTS representation one of appliance of supporter of telecommunicationsnetwork. The development of BTS have to each other in circuit by other BTS or which have been planned.The situation BTS in circuit between other BTS without obstacle are called Line of Sight (LoS. Thetopographic survey is method of survey work to make sure the Line of Sight BTS. The topographic surveyconsist of GPS survey and study map for determination of high of BTS antenna and the Line of Sight ofBTS can be made.

  13. A Pressure Control Method for Emulsion Pump Station Based on Elman Neural Network

    Directory of Open Access Journals (Sweden)

    Chao Tan

    2015-01-01

    Full Text Available In order to realize pressure control of emulsion pump station which is key equipment of coal mine in the safety production, the control requirements were analyzed and a pressure control method based on Elman neural network was proposed. The key techniques such as system framework, pressure prediction model, pressure control model, and the flowchart of proposed approach were presented. Finally, a simulation example was carried out and comparison results indicated that the proposed approach was feasible and efficient and outperformed others.

  14. A RECONFIGURABLE ELECTROMAGNETIC BANDGAP STRUCTURE FOR A BEAM STEERING BASE STATION ANTENNA

    OpenAIRE

    Boutayeb, Halim; Brillat, T.; Daniel, J.P.; Gadot, F.; Garel, P.Y.; De Lustrac, A.; Mahdjoubi, Kouroch; Ratajczak, P.; Tarot, Anne-Claude

    2004-01-01

    The purpose of this communication is to present the works of a French Industry and Research sponsorized project (RNRT Project) named "BIP" [1]. The goal of this project was to design a beam steering multi-band (GSM/DCS/UMTS) base station antenna. After a presentation of the different partners, we will show how we would solved the problem of the beam steering antenna with a controllable Electromagnetic BandGap (EBG) structure and we will present the results of simulations and experiments in or...

  15. A demonstration HTS base station sub-system for mobile communications

    International Nuclear Information System (INIS)

    A demonstration sub-system for mobile communications was developed. In this system, a high-temperature superconducting (HTS) microstrip bandpass filter on r-plane sapphire substrate was designed to have a quasi-elliptic function response, which was aimed at covering the whole receive band of DCS 1800 base station, i.e. 1710-1785 MHz. This filter was then integrated with a low noise amplifier (LNA) and a pulse tube cryocooler, forming a demonstration sub-system. Satisfactory performance of this system was achieved. (author)

  16. RIGOROUS FULL-WAVE ANALYSIS OF THE BASE-STATION ANTENNAS

    Institute of Scientific and Technical Information of China (English)

    Chen Shengbing; Zhang Fushun; Jiao Yongchang; Sun Baohua

    2002-01-01

    Rigorous analysis of the Base-Station (BS) antennas with reflector is made in this letter. The wire-grid modeling of BS antenna is established. In order to improve the solution accuracy and efficiency, some efficient techniques such as three-term sinusoidal interpolation basis function and discrete wavelet transform are used. Numerical examples considered here are the typical vertically polarized and the dual-polarized BS antennas. The calculated results for the vertically polarized BS antenna are in good agreement with the measured data, which show that the analysis modeling used is accurate and reliable.

  17. DESIGN OF A SHAPED BEAM BASE STATION ANTENNA USING GENETIC ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    Liu Ying; Bu Antao; Gong Shuxi; Shen Zongzhen; Xiao Liangyong

    2003-01-01

    Genetic algorithm is used to optimize a base station antenna in order to achieve a shaped beam in a frequency band. During the optimization process, different antenna models have been evaluated using the Method of Moment (MoM). As a result of this optimization, a shaped beam antenna with suppressed sidelobe smaller than -18dB, backlobe smaller than -30dB and filled null point larger than -15dB is achieved. The proposed method is closer to reality compared with previous methods and can be used to optimize complicated antennas. The result is very useful for engineering and theoretical analysis.

  18. Strategy for an Australian research program into possible health issues associated with exposure to communications radiofrequencies

    International Nuclear Information System (INIS)

    Telecommunications in Australia has expanded rapidly in recent years. Growth in personal and mobile telecommunications has resulted in the construction of numerous base station antennae. These antennae are highly visible and are often sited in public or high traffic areas. There has also been an increase in the number of mobile phone handsets-the small, low power transmitters held close to the head during use. In the last 2-3 years there has been considerable public concern and media coverage about the possible health effects resulting from exposure to radiofrequency fields or radiofrequency radiation (RFR) which is used for communicating between handsets and base stations. National and international scientific opinion is that at the present time there is no substantiated evidence that exposure to RFR at levels typically found in the community results in adverse health effects but there is a need for further study. Although considerable research has been undertaken on exposure to extremely low frequency (ELF) 50/60 Hz fields, limited information is available on human exposure to RFR in the frequency range 100 kHz to 300 GHz. The frequency bands used for the mobile phone networks are mainly in the 800-900 MHz spectrum region with developing technology using the 1.8-2.2 GHz band. In the digital GSM system pulse modulation occurs at 217 Hz. Radio and television broadcasts are in the 0.3-600 MHz range. Other sources include paging systems, personal communication systems and industrial sources. The discussion paper outlines possible priority areas and makes recommendation for further study under the Australian Research Program

  19. Station Based Polynomial Modeling of the local ionospheric Vertical Total Electron Content (VTEC) using Particle Filter

    Science.gov (United States)

    Erdogan, Eren; Onur Karslioglu, Mahmut; Durmaz, Murat; Aghakarimi, Armin

    2014-05-01

    In this study, particle filter (PF) which is mainly based on the Monte Carlo simulation technique has been carried out for polynomial modeling of the local ionospheric conditions above the selected ground based stations. Less sensitivity to the errors caused by linearization of models and the effect of unknown or unmodeled components in the system model is one of the advantages of the particle filter as compared to the Kalman filter which is commonly used as a recursive filtering method in VTEC modeling. Besides, probability distribution of the system models is not necessarily required to be Gaussian. In this work third order polynomial function has been incorporated into the particle filter implementation to represent the local VTEC distribution. Coefficients of the polynomial model presenting the ionospheric parameters and the receiver inter frequency biases are the unknowns forming the state vector which has been estimated epoch-wise for each ground station. To consider the time varying characteristics of the regional VTEC distribution, dynamics of the state vector parameters changing permanently have been modeled using the first order Gauss-Markov process. In the processing of the particle filtering, multi-variety probability distribution of the state vector through the time has been approximated by means of randomly selected samples and their associated weights. A known drawback of the particle filtering is that the increasing number of the state vector parameters results in an inefficient filter performance and requires more samples to represent the probability distribution of the state vector. Considering the total number of unknown parameters for all ground stations, estimation of these parameters which were inserted into a single state vector has caused the particle filter to produce inefficient results. To solve this problem, the PF implementation has been carried out separately for each ground station at current time epochs. After estimation of unknown

  20. Analysis of local ionospheric variability based on SVD and MDS at low-latitude GNSS stations

    Science.gov (United States)

    Dabbakuti, J. R. K. Kumar; Devanaboyina, Venkata Ratnam; Kanchumarthi, S. Ramesh

    2016-06-01

    Investigation of ionospheric anomalies during equatorial and low latitude is of major concern for modeling and global navigation satellite system (GNSS) applications. Total electron content (TEC) varies with the ionospheric conditions, which will lead to the errors in the global positioning system (GPS) measurements. It is therefore a method that is necessary to characterize the ionospheric anomalies for satellite-based navigation systems. In this study, characterization of ionospheric variations based on the singular value decomposition (SVD) and classical multidimensional scaling (MDS) methods was studied. The yearly and daily variations are decomposed from the GPS-TEC, international reference ionosphere (IRI) 2007 and IRI 2012 models TEC over the three low-latitude GNSS stations located at Koneru Lakshmaiah University (KLU-Guntur), Hyderabad and Bangalore, respectively. From the results, it is found that there is a strong correlation between GPS-TEC and IRI models. The correlation coefficient for the first three singular values is more than 0.86. From this, it is possible to reconstruct more than 85 % of the variability contained in global GPS-derived VTEC data (for year 2013) by using only the first three modes. The semiannual variation has maximum value during March-April and September-October and has minimum value during June-July. It is observed that the annual variations have maximum value in summer and minimum value in winter, and the amplitudes decrease with increasing latitude. Further, opposite latitudinal asymmetry among annual and semiannual variations for three GNSS stations is noticed. SVD and MDS methods clearly show time-varying characteristics and the absence of the winter anomaly at low-latitude GNSS stations.

  1. Energy-Aware Base Stations: The Effect of Planning, Management, and Femto Layers

    Directory of Open Access Journals (Sweden)

    G. Koutitas

    2014-01-01

    Full Text Available We compare the performance of three base station management schemes on three different network topologies. In addition, we explore the effect of offloading traffic to heterogeneous femtocell layer upon energy savings taking into account the increase of base station switch-off time intervals. Fairness between mobile operator and femtocell owners is maintained since current femtocell technologies present flat power consumption curves with respect to served traffic. We model two different user-to-femtocell association rules in order to capture realistic and maximum gains from the heterogeneous network. To provide accurate findings and a holistic overview of the techniques, we explore a real urban district where channel estimations and power control are modeled using deterministic algorithms. Finally, we explore energy efficiency metrics that capture savings in the mobile network operator, the required watts per user and watts per bitrate. It is found that the newly established pseudo distributed management scheme is the most preferable solution for practical implementations and together with the femotcell layer the network can handle dynamic load control that is regarded as the basic element of future demand response programs.

  2. Distributed Linear Precoder Optimization and Base Station Selection for an Uplink Heterogeneous Network

    CERN Document Server

    Hong, Mingyi

    2012-01-01

    In a heterogeneous wireless cellular network, each user may be covered by multiple access points such as macro/pico/relay/femto base stations (BS). An effective approach to maximize the sum utility (e.g., system throughput) in such a network is to jointly optimize users' linear procoders as well as their base station associations. In this paper we first show that this joint optimization problem is NP-hard and thus is difficult to solve to global optimality. To find a locally optimal solution, we formulate the problem as a noncooperative game in which the users and the BSs both act as players. We introduce a set of new utility functions for the players and show that every Nash equilibrium (NE) of the resulting game is a stationary solution of the original sum utility maximization problem. Moreover, we develop a best-response type algorithm that allows the players to distributedly reach a NE of the game. Simulation results show that the proposed distributed algorithm can effectively relieve local BS congestion ...

  3. Human-factors-based implementation of the remote characterization system high-level control station

    International Nuclear Information System (INIS)

    The detection and characterization of buried objects and materials is an important first step in the restoration of the numerous US Department of Energy (DOE) and US Department of Defense waste disposal sites. DOE, through its Environmental Restoration and Waste Management Robotics and Technology Development Program, has developed the Remote Characterization System (RCS) to address the needs of remote subsurfacecharacterization. The RCS consists of a low-metal-content (low-metallic-signature) remotely piloted vehicle, a high-level control station (HLCS) where operators can remotely control the vehicle and analyze real-time data from sensors, and an array of sensors that can be chosen to meet the survey task at hand. Communication between the vehicle and the base station is handled by a radio link. Site mapping is made possible through the use of geopositioning satellite data. The primary mode of vehicle operation is teleoperation, but provision has been made for semiautonomous or supervisory control that allows for automated sitesurvey on simple sites. Data analysis and display is supported for both real-time observation and postprocessing of data. The particular emphasis of this paper documents the human-factors-based design influences on the HLCS and describes the design in detail

  4. Timepix-based radiation environment monitor measurements aboard the International Space Station

    International Nuclear Information System (INIS)

    A number of small, single element radiation detectors, employing the CERN-based Medipix2 Collaboration's Timepix Application Specific Integrated Circuit (ASIC) coupled to a specially modified version of the USB-Lite interface for that ASIC provided by the Institute for Experimental and Applied Physics (IEAP) at the Czech Technical University in Prague, have been developed at the University of Houston and NASA Johnson Space Center. These detectors, officially designated by NASA as Radiation Environment Monitors (REMs), were deployed aboard the International Space Station in late 2012. Six REM units are currently operating on Station Support Computers (SSCs) and returning data on a daily basis. The associated data acquisition software on the SSCs provides both automated data collection and transfer, as well as algorithms to handle adjustment of acquisition rates and recovery and restart of the acquisition software. A suite of ground software analysis tools has been developed to allow rapid analysis of the data and provides a ROOT-based framework for extending data analysis capabilities

  5. Radiofrequency uvulopalatoplasty for primary snoring.

    Directory of Open Access Journals (Sweden)

    Seyed Hadi Samimi Ardestani

    2013-08-01

    Full Text Available Simple snoring is a social problem, one that can gravely affect the patient's married life. About 40% of men and 20% of women are affected, and it often goes along with sleep-disordered breathing. Up to now various surgical techniques have been defined such as UPPP(uvulopalatopharyngo plasty, and laser-assisted uvulopalatoplasty (LAUP. Among the surgical methods, RAUP (radiofrequency assisted uvulopalatoplasty is a minimal invasive, an easy performed, and time and cost effective one. We designed a before and after a clinical trial. The inclusion criteria were age >18 years, complaint of nocturnal snoring, have a bed partner to assess snoring, AHI<5 events per hour in the polysomnography, malampathy score (soft palate position I or II, an elongated uvula, grade I and II of pharyngeal webbing and patient consent was needed too. A 10-score visual analog scale (VAS of snoring severity was completed by bed partner. All of 35 included patients underwent RAUP under local anesthesia by the same expert surgeon. After 3 months, 6 months and one year, subjective snoring decreased significantly compared to the preoperative period. The decline in VAS in 6 month compared to 3 months postoperatively, was not significant (P=0.223. When comparing 1 year and 6 months after treatment, the VAS scores were increased, but they were not significant (From 1.8 to 1.9, P=0.78. Three months after treatment minor complications consisted of: nasal regurgitation in 2 patients (5.7%, nasal speech in 2 (5.7% and exacerbation of snoring in 2 (5.7% patients.There was no major complication including mucosal laceration, uvular damage and obstruction of the airway. The rate of snoring decrease did not correlate with age, sex and BMI. Based on this study and literature review, it seems RAUP is a safe surgery, which may decrease symptoms of snoring, at least, in short-term follow-up.

  6. A computer-based system for environmental impact assessment (EIA) applications to energy power stations in Turkey: CEDINFO

    International Nuclear Information System (INIS)

    Environmental impact assessment (EIA) is a tool for decision makers to take into account the possible effects of a proposed project on the environment and is also a process for collecting the data related to a project design and project area. Different techniques are used for the EIA process. In recent years, including the design and development of databases, classification systems, computer models and expert systems have been used extensively in impact assessment studies. Knowledge-based systems referred to as expert systems and different computer-based systems are an emerging technology in information processing and are becoming increasingly useful tools in different applications areas including EIA studies. Their use for EIA has been quite limited in developing countries, because of the constraints on resources, particularly in expertise and data. In this study, a knowledge-based software-CEDINFO-developed by authors was introduced. CEDINFO to be used for EIA practices on energy-generating stations was designed based on the legal EIA process in Turkey. According to the EIA Regulation enacted in Turkey in 1993, energy-generating stations (thermal power station, hydraulic station, nuclear station) in different categories require mandatory EIA reports duly approved by The Ministry of Environment and Forestry before their construction. CEDINFO primarily aims to provide educational support for EIA practices and decision-makers on energy-generating stations

  7. A Redox-Controllable Molecular Switch Based on Weak Recognition of BPX26C6 at a Diphenylurea Station

    Directory of Open Access Journals (Sweden)

    Jia-Cheng Chang

    2015-01-01

    Full Text Available The Na+ ion–assisted recognition of urea derivatives by BPX26C6 has allowed the construction of a redox-controllable [2]rotaxane-type molecular switch based on two originally very weakly interacting host/guest systems. Using NOBF4 to oxidize the triarylamine terminus into a corresponding radical cation attracted the macrocyclic component toward its adjacent carbamate station; subsequent addition of Zn powder moved the macrocyclic component back to its urea station.

  8. International Space Station-Based Electromagnetic Launcher for Space Science Payloads

    Science.gov (United States)

    Jones, Ross M.

    2013-01-01

    A method was developed of lowering the cost of planetary exploration missions by using an electromagnetic propulsion/launcher, rather than a chemical-fueled rocket for propulsion. An electromagnetic launcher (EML) based at the International Space Station (ISS) would be used to launch small science payloads to the Moon and near Earth asteroids (NEAs) for the science and exploration missions. An ISS-based electromagnetic launcher could also inject science payloads into orbits around the Earth and perhaps to Mars. The EML would replace rocket technology for certain missions. The EML is a high-energy system that uses electricity rather than propellant to accelerate payloads to high velocities. The most common type of EML is the rail gun. Other types are possible, e.g., a coil gun, also known as a Gauss gun or mass driver. The EML could also "drop" science payloads into the Earth's upper

  9. Joint Base Station Clustering and Beamformer Design for Partial Coordinated Transmission in Heterogenous Networks

    CERN Document Server

    Hong, Mingyi; Baligh, Hadi; Luo, Zhi-Quan

    2012-01-01

    We consider the interference management problem in a multicell MIMO heterogenous network. Within each cell there are a large number of distributed micro/pico base stations (BSs) that can be potentially coordinated for joint transmission. To reduce coordination overhead, we consider user-centric BS clustering so that each user is served by only a small number of (potentially overlapping) BSs. Thus, given the channel state information, our objective is to jointly design the BS clustering and the linear beamformers for all BSs in the network. In this paper, we formulate this problem from a {sparse optimization} perspective, and propose an efficient algorithm that is based on iteratively solving a sequence of group LASSO problems. A novel feature of the proposed algorithm is that it performs BS clustering and beamformer design jointly rather than separately as is done in the existing approaches for partial coordinated transmission. Moreover, the cluster size can be controlled by adjusting a single penalty paramet...

  10. Risk-based Inspection Guide for the Susquehanna Station HPCI system

    International Nuclear Information System (INIS)

    The High Pressure Coolant Injection (HPCI) system has been examined from a risk perspective. A system Risk-based Inspection Guide (S-RIG) has been developed as an aid to HPCI system inspections at the Susquehanna Steam Electric Station (SSES) which is operated by Pennsylvania Power ampersand Light (PP ampersand L). Included in this S-RIG is a discussion of the role of HPCI in mitigating accidents and a presentation of PRA-based failure modes which could prevent proper operation of the system. The S-RIG uses industry operating experience, including plant-specific illustrative examples, to augment the basic PRA failure modes. It is designed to be used as a reference for both routine inspections and the evaluation of the significance of component failures

  11. Monte Carlo dose calculation using a cell processor based PlayStation 3 system

    International Nuclear Information System (INIS)

    This study investigates the performance of the EGSnrc computer code coupled with a Cell-based hardware in Monte Carlo simulation of radiation dose in radiotherapy. Performance evaluations of two processor-intensive functions namely, HOWNEAR and RANMARGET in the EGSnrc code were carried out basing on the 20-80 rule (Pareto principle). The execution speeds of the two functions were measured by the profiler gprof specifying the number of executions and total time spent on the functions. A testing architecture designed for Cell processor was implemented in the evaluation using a PlayStation3 (PS3) system. The evaluation results show that the algorithms examined are readily parallelizable on the Cell platform, provided that an architectural change of the EGSnrc was made. However, as the EGSnrc performance was limited by the PowerPC Processing Element in the PS3, PC coupled with graphics processing units or GPCPU may provide a more viable avenue for acceleration.

  12. vNet Zero Energy for Radio Base Stations- Balearic Scenario

    DEFF Research Database (Denmark)

    Sabater, Pere; Mihovska, Albena Dimitrova; Pol, Andreu Moia;

    2016-01-01

    The Balearic Islands have one of the best telecommunications infrastructures in Spain, with more than 1500 Radio Base Stations (RBS) covering a total surface of 4.991,66 km². This archipelago has high energy consumption, with high CO2 emissions, due to an electrical energy production system mainly...... based on coal and fossil fuels which is not an environmentally sustainable scenario. The aim of this study is to identify the processes that would reduce the energy consumption and greenhouse gas emissions, designing a target scenario featuring "zero CO2 emissions" and "100% renewable energies" in RBS....... The energy costs, CO2 emissions and data traffic data used for the study are generated by a sample of RBS from the Balearic Islands. The results are shown in terms of energy performance for a normal and net zero emissions scenarios....

  13. Risk-based Inspection Guide for the Susquehanna Station HPCI system

    Energy Technology Data Exchange (ETDEWEB)

    Travis, R; Higgins, J; Gunther, W; Shier, W [Brookhaven National Lab., Upton, NY (United States)

    1992-11-01

    The High Pressure Coolant Injection (HPCI) system has been examined from a risk perspective. A system Risk-based Inspection Guide (S-RIG) has been developed as an aid to HPCI system inspections at the Susquehanna Steam Electric Station (SSES) which is operated by Pennsylvania Power & Light (PP&L). Included in this S-RIG is a discussion of the role of HPCI in mitigating accidents and a presentation of PRA-based failure modes which could prevent proper operation of the system. The S-RIG uses industry operating experience, including plant-specific illustrative examples, to augment the basic PRA failure modes. It is designed to be used as a reference for both routine inspections and the evaluation of the significance of component failures.

  14. WORKSHOP: Radiofrequency superconductivity

    International Nuclear Information System (INIS)

    Full text: With superconducting radiofrequency playing a major role in the push for new machines to break fresh physics frontiers, it has become a tradition for experts and newcomers in this field from all over the world to meet every second year to hear progress reports from laboratories and to discuss common problems and possible solutions. The sixth such workshop was held from 4-8 October under the chairmanship of Ron Sundelin at the Continuous Electron Beam Accelerator Facility (CEBAF) under construction in Newport News, Virginia. With 170 participants from 14 countries including Eastern Europe and China, it reflected the growing interest in the field - looking back to 1984, when CERN was the host laboratory, the second workshop had less than 100 participants. The CEBAF meeting began with laboratory status reports, covering both high beam energy ('high beta') applications with 'spherical' cavities (as with CERN's LEP200), all using niobium as superconductor and working between 352 MHz and 3 GHz, and lower energy (low beta') applications with geometrically more complicated shapes such as quarter or half wave, split ring or spoke resonators, some using electrodeposited lead as superconductor and working around 100 MHz. During these talks it became clear that more and more laboratories have focused on routine problems, such as reliable series production and testing, running cavities with ancillaries in the machines, or building complete prototypes for projects to be approved by critical funding authorities. This contrasts with the heady days just a few years ago when - at least in the high beta community - the main objective was to explore new ideas. State-of-the-art summaries showed how at 1.3 and 3 GHz 25-30 MV/m have been reached by several laboratories using different preparation methods. Newer developments for common problems included r.f. windows, couplers, controls, and especially field emission, public enemy number one for

  15. Heat flows and energetic behavior of a telecommunication radio base station

    International Nuclear Information System (INIS)

    This paper shows a study on energetic consumption of BTSs (Base Transceiver Stations) for mobile communication, related to conditioning functions. An energetic “thermal model” of a telecommunication station is proposed and studied. The results have been validated with a BTS in central Italy, showing good agreement. Findings show a substantial high internal-external temperature difference in the containing shelter, particularly during daytime and warm months, due to sources of heat (equipment, external temperature and sun radiation) and to the difficulty in spread the warmth out. The necessity to keep the operating temperatures within a given range for the correct functioning of the electronic equipment requires the use of conditioning setups, and this significantly increases the energetic demand of the whole system. The analysis of thermal flows across the shelter can help to gather further data on its temperature behavior and to devise practical measures to lower the power demand, while keeping the operating parameters in the suggested ranges. The investigation of some operating parameters of the equipment and of the shelter, such as threshold set-points, air vent area, external wall transmittance and reflectivity, suggests annual energy savings between 10% and 30%. - Highlights: • A heat flow model for a telecommunication shelter was created. • Successful matching of the model and real-life cases was obtained. • The model addresses how each parameter affects energy consumption. • Reasonably savings of up to 30% of consumed energy can be expected

  16. A microcontroller-based data-acquisition system for meteorological station monitoring

    International Nuclear Information System (INIS)

    This paper presents a study of feasibility of different existing methodologies linked to field's data acquisition from remote meteorological stations. The data transmission serves to collect field's meteorological information, such as temperature, humidity and radiation. In our study the experimental data is registered in a weather station located about 100 km from University of Almeria. Various existing techniques are studied, especially Radio, GSM (global system of mobile communication) and GPRS (general packet radio service). In the result of these studies has been designed a system of field's data acquisition (herein referred as Meteologger) which we are going to present in this paper. The system is based on an ATmega 16 microcontroller, which scans 8 sensors together at any programmable intervals. This paper presents the study of the mentioned project, application and some main characteristics of the prototype system and its program. We attempt to implement the system, and subsequently present the performance of tests regarding the mentioned system. To verify its functioning some comparison of this measurement system with two others commercial data-acquisition system (Campbell and Hobo H8) has been carried out

  17. Georeferencing of ground-based LIDAR data using continuously operating reference stations

    Science.gov (United States)

    Altuntas, Cihan; Karabork, Hakan; Tusat, Ekrem

    2014-11-01

    Terrestrial laser scanning has been used for various outdoor visualizations such as urban, construction, excavations, and land topography. Since laser scanning data have their own local coordinates in each station, a three-dimensional point cloud model of the object of interest is created in the local coordinate system by the combination of these measurements. For spatial queries and computations, the point cloud and other spatial data should be combined in a common coordinate system. In this study, a terrestrial laser scanner (TLS) and global navigation satellite system (GNSS) receiver were integrated for the registration of the laser scanner measurements into the geodetic coordinate system. Two georeferencing methods based on the continuously operating reference stations in the network Turkey (CORS-TR) were introduced. After the building was modelled by integrating the TLS and the GNSS receiver, the point cloud model that was created was registered to the international terrestrial reference frame. The registration was performed with 0.05 m root mean square error for the two georeferencing methods.

  18. Optimization of maintenance programme at Daya Bay Nuclear Power Station based on RCM analysis results

    International Nuclear Information System (INIS)

    This paper begins with an introduction to Guangdong Daya Bay Nuclear Power Station (GNPS) and gives a simple introduction to the operations and maintenance documentation system at GNPS. It then will review the maintenance program guidelines base and the associated problems prior to the application of reliability centered maintenance (RCM). How RCM was implemented at GNPS, how the results of RCM analysis were used to optimize the maintenance program and test program, and what is the interface between RCM and the existing maintenance program will be shown. Next, it will show the successful implementation of RCM at GNPS resulted in the following changes: A new understanding of equipment failure challenges operations and maintenance beliefs, maintenance concepts undergo a large change, maintenance program and periodic testing program are continuously modified and optimized, new on-condition maintenance technologies are introduced, non-productive scheduled overhauls are discarded, maintenance costs are effectively controlled, maintenance appropriateness has improved, management of hidden failures is more effective and timely. It will show the benefit of greater equipment reliability brought about by all of these changes, which in turn increases the reliability and safety of the entire power station. (author)

  19. Design and Development of a CPCI-Based Electronics Package for Space Station Experiments

    Science.gov (United States)

    Kolacz, John S.; Clapper, Randy S.; Wade, Raymond P.

    2006-01-01

    The NASA John H. Glenn Research Center is developing a Compact-PCI (CPCI) based electronics package for controlling space experiment hardware on the International Space Station. Goals of this effort include an easily modified, modular design that allows for changes in experiment requirements. Unique aspects of the experiment package include a flexible circuit used for internal interconnections and a separate enclosure (box in a box) for controlling 1 kW of power for experiment fuel heating requirements. This electronics package was developed as part of the FEANICS (Flow Enclosure Accommodating Novel Investigations in Combustion of Solids) mini-facility which is part of the Fluids and Combustion Facility s Combustion Integrated Rack (CIR). The CIR will be the platform for future microgravity combustion experiments and will reside on the Destiny Module of the International Space Station (ISS). The FEANICS mini-facility will be the primary means for conducting solid fuel combustion experiments in the CIR on ISS. The main focus of many of these solid combustion experiments will be to conduct applied scientific investigations in fire-safety to support NASA s future space missions. A description of the electronics package and the results of functional testing are the subjects of this report. The report concludes that the use of innovative packaging methods combined with readily available COTS hardware can provide a modular electronics package which is easily modified for changing experiment requirements.

  20. The effect of the Electromagnetic fields Non Ionized radiations of cellular base station on human health

    International Nuclear Information System (INIS)

    Given the enormous expansion in the installation of Cellular Base Stations (CBS) on building tops, and the concern of residents, neighbouring those stations, of contracting serious diseases, because of their exposure to electromagnetic radiations, transmitted by (CBS) antennas, a scientific and statistical study has been conducted on residents neighbouring (CBS)s in several quarters of Damascus. The aim of the study is to identify the effect of the CBS's diation on the human body. The Study involves the following steps: 1. Site measurements have been carried out to evaluate the energy density, the strength of electrical and magnetic fields of the electromagnetic radiation, emitted from the CBS antennas, close to the buildings with (SBC)s on top, taking distance into account, in order to know the range of residents' exposure [to electromagnetic radiation], close to and far away from the CBS's antennas 2. Field Statistical Health Questionnaires of residents adjacent to ,or far away from (SBC)s,have been carried out, in order establish the link between the electromagnetic radiation transmitted by (SBC)s and diseases developed by nearby residents. Finally, very important scientific findings have been obtained. (author)

  1. Wind Energy Based Electric Vehicle Charging Stations Sitting. A GIS/Wind Resource Assessment Approach

    Directory of Open Access Journals (Sweden)

    George Xydis

    2015-11-01

    Full Text Available The transportation sector is severely correlated with major problems in environment, citizens’ health, climate and economy. Issues such as traffic, fuel cost and parking space have make life more difficult, especially in the dense urban environment. Thus, there is a great need for the development of the electric vehicle (EV sector. The number of cars in cities has increased so much that the current transportation system (roads, parking places, traffic lights, etc. cannot accommodate them properly. The increasing number of vehicles does not affect only humans but also the environment, through air and noise pollution. According to EPA, the 39.2% of total gas emissions in 2007 was caused by transportation activities. Studies have shown that the pollutants are not only gathered in the major roads and/or highways but can travel depending on the meteorological conditions leading to generic pollution. The promotion of EVs and the charging stations are both equally required to be further developed in order EVs to move out of the cities and finally confront the range problem. In this work, a wind resource and a GIS analysis optimizes in a wider area the sitting of wind based charging stations and proposes an optimizing methodology.

  2. Assessment of electromagnetic fields intensity emitted by cellular phone base stations in surrounding flats - a preliminary study

    International Nuclear Information System (INIS)

    A rapid development of mobile telecommunications (MT) has resulted in an increased concern about possible detrimental health effects of electromagnetic fields (EMFs) emitted by MT systems, and by MT base stations in particular. Research into EMFs effects on the health of inhabitants living in their vicinity requires first of all a solid assessment of the exposure level. Up to now, the reports in this field have been rather scant. This article presents the results of preliminary measurements of EMFs fields in selected flats around selected base stations in the city of Lodz. Measurements of electric field strength, E, to assess EMF exposure were based on the standard procedures currently in force in Poland. As the study is regarded as a preliminary one, the measurements were conducted in buildings with the expected largest radiation. The measurements show that in the flats located up to 500 m from the base station, EMFs are within the limits specified by relevant Polish regulations on the general public and environmental protection. It was also observed that in a few (less than 10%) flats the field with E exceeded 0.8 V/m. The results show that there are no correlations between electric field strength and distance between the flat and the base station. Therefore, the distance from the base station cannot be used to represent the exposure rate; to determine the latter, EMF measurements are necessary. (author)

  3. Measurements of RF/MW radiation emitted from selected mobile-phone base-stations in Sudan

    International Nuclear Information System (INIS)

    Scattering of mobile-phone base-stations within populated areas is a source of some misscomfortableness to many people. As there is no one agreed on safety level for the MPE for RF/MW all over the world, measurements of radiation emitted from base-stations is a necessity. In this work we screened out some mobile-phone base-stations inside and outside Khartoum city in Sudan. Measurements were done indoor and outdoor to maximum horizontal distance of about 300 m from the base of the base-stations. Results obtained were then compared to the maximum and minimum MPE values admitted in different countries in the world. The maximum MPE value (i.e- 0.57 mW/cm2) consider only the thermal effects of the RF/MW, while other values tend to reduce the exposure limits to as minimum as possible for safety considerations (considering non-thermal effects). Some of the values obtained were consistent with some reported biological effects. We recommended the removal of some base-stations from sensitive areas like schools, kindergardens, hostels, hospitals, etc. (author)

  4. Electromagnetic impact by microcellular base stations: analysis and guidelines for a correct setting up

    International Nuclear Information System (INIS)

    During the last few years the development of mobile communications has required ever increasing number of base stations for both existing mobile operators and new ones. More and more users ask for a higher quality services so new technological solutions have been studied and applied to assure effective coverage for given geographical areas, as in squares or narrow streets, characterized by a very high traffic demand or where coverage by usual macro cells is very difficult. On the other side, modern societies of developed countries ask for a better and better quality of life and appropriate government policies. Several studies of national and international scientific organizations have been performed and are still in progress to establish any possible adverse effects on human health of non-ionizing radiation exposure. So, many governments, forced by public opinion pressure, have produced specific standards in agreement with scientific organization guidelines and prudent avoidance politics too. Nowadays, designing their networks, mobile operators have to respect requirements contained in these standards. So a hierarchical cellular system have been recently proposed to comply more easily with both coverage requirements and lower exposure limits. This new coverage strategy of geographical areas requires the presence of microcells beside the usual macro cells. In this paper the study of the distribution of the electromagnetic field levels produced by microcellular base stations characterized by different features and configurations is presented, in order to define a few guidelines for the correct setting up of antennas in compliance with current standard requirements. This is obtained comparing results of theoretical modeling, based on the radio electrical characteristics of each sources, and measurements data. Results achieved by measurements performed on a preliminary sample of microcells have been presented in this work

  5. A lightweight neighbor-info-based routing protocol for no-base-station taxi-call system.

    Science.gov (United States)

    Zhu, Xudong; Wang, Jinhang; Chen, Yunchao

    2014-01-01

    Since the quick topology change and short connection duration, the VANET has had unstable routing and wireless signal quality. This paper proposes a kind of lightweight routing protocol-LNIB for call system without base station, which is applicable to the urban taxis. LNIB maintains and predicts neighbor information dynamically, thus finding the reliable path between the source and the target. This paper describes the protocol in detail and evaluates the performance of this protocol by simulating under different nodes density and speed. The result of evaluation shows that the performance of LNIB is better than AODV which is a classic protocol in taxi-call scene. PMID:24737984

  6. Integrating stations from the North America Gravity Database into a local GPS-based land gravity survey

    Science.gov (United States)

    Shoberg, Thomas G.; Stoddard, Paul R.

    2013-01-01

    The ability to augment local gravity surveys with additional gravity stations from easily accessible national databases can greatly increase the areal coverage and spatial resolution of a survey. It is, however, necessary to integrate such data seamlessly with the local survey. One challenge to overcome in integrating data from national databases is that these data are typically of unknown quality. This study presents a procedure for the evaluation and seamless integration of gravity data of unknown quality from a national database with data from a local Global Positioning System (GPS)-based survey. The starting components include the latitude, longitude, elevation and observed gravity at each station location. Interpolated surfaces of the complete Bouguer anomaly are used as a means of quality control and comparison. The result is an integrated dataset of varying quality with many stations having GPS accuracy and other reliable stations of unknown origin, yielding a wider coverage and greater spatial resolution than either survey alone.

  7. A Study on the Scheduling of Large-Scaled PV Power Station Output based on Solar Radiation Forecast

    Science.gov (United States)

    Takayama, Satoshi; Iwasaka, Yuji; Hara, Ryoichi; Kita, Hiroyuki; Ito, Takamitsu; Ueda, Yoshinobu; Miwa, Shuya; Matsuno, Naoya; Takitani, Katsuyuki; Yamaguchi, Koji

    Recently, photovoltaic generation (PV) attracts great attentions as a countermeasure against the global warming and the depletion problem of fossil energy resources in the world. However, it is known that a PV output fluctuates due to the insolation variation. Unstable power from a PV power station may cause some negative impact to the power system. Therefore, to utilize a PV power station in substitution for an existing power supply, improvement in controllability and adjustability of generation output is very important factor. In this paper, a new method for scheduling and rescheduling the PV power station output based on the solar radiation forecast are proposed. The scheduling and rescheduling method using NAS battery and solar radiation forecast from the economic perspective are proposed and the validity of the proposed method is ascertained through case studies using the data measured in the Wakkanai PV power station.

  8. Mobile phone base stations and adverse health effects: phase 1 of a population-based, cross-sectional study in Germany

    DEFF Research Database (Denmark)

    Blettner, M; Schlehofer, B; Breckenkamp, J; Kowall, B; Schmiedel, S; Reis, U; Potthoff, P; Schüz, J; Berg-Beckhoff, Gabriele

    2009-01-01

    OBJECTIVE: The aim of this first phase of a cross-sectional study from Germany was to investigate whether proximity of residence to mobile phone base stations as well as risk perception is associated with health complaints. METHODS: The researchers conducted a population-based, multi-phase, cross......-sectional study within the context of a large panel survey regularly carried out by a private research institute in Germany. In the initial phase, reported on in this paper, 30,047 persons from a total of 51,444 who took part in the nationwide survey also answered questions on how mobile phone base stations...... participants were concerned about adverse health effects of mobile phone base stations, while an additional 10.3% attributed their personal adverse health effects to the exposure from them. Participants who were concerned about or attributed adverse health effects to mobile phone base stations and those living...

  9. Low-cost extrapolation method for maximal lte radio base station exposure estimation: Test and validation

    International Nuclear Information System (INIS)

    An experimental validation of a low-cost method for extrapolation and estimation of the maximal electromagnetic-field exposure from long-term evolution (LTE) radio base station installations are presented. No knowledge on down-link band occupation or service characteristics is required for the low-cost method. The method is applicable in situ. It only requires a basic spectrum analyser with appropriate field probes without the need of expensive dedicated LTE decoders. The method is validated both in laboratory and in situ, for a single-input single-output antenna LTE system and a 2x2 multiple-input multiple-output system, with low deviations in comparison with signals measured using dedicated LTE decoders. (authors)

  10. Energy-Efficient Network Transmission between Satellite Swarms and Earth Stations Based on Lyapunov Optimization Techniques

    Directory of Open Access Journals (Sweden)

    Weiwei Fang

    2014-01-01

    Full Text Available The recent advent of satellite swarm technologies has enabled space exploration with a massive number of picoclass, low-power, and low-weight spacecraft. However, developing swarm-based satellite systems, from conceptualization to validation, is a complex multidisciplinary activity. One of the primary challenges is how to achieve energy-efficient data transmission between the satellite swarm and terrestrial terminal stations. Employing Lyapunov optimization techniques, we present an online control algorithm to optimally dispatch traffic load among different satellite-ground links for minimizing overall energy consumption over time. Our algorithm is able to independently and simultaneously make control decisions on traffic dispatching over intersatellite-links and up-down-links so as to offer provable energy and delay guarantees, without requiring any statistical information of traffic arrivals and link condition. Rigorous analysis and extensive simulations have demonstrated the performance and robustness of the proposed new algorithm.

  11. Determinants and stability over time of perception of health risks related to mobile phone base stations

    DEFF Research Database (Denmark)

    Kowall, Bernd; Breckenkamp, Jürgen; Blettner, Maria;

    2012-01-01

    about other environmental and health risks, is associated with psychological strain, and is stable on the individual level over time. METHODS: Self-administered questionnaires filled in by 3,253 persons aged 15-69 years in 2004 and 2006 in Germany. RESULTS: Risk perception of MPBS was strongly...... 2004 expressed these concerns again 2 years later, the corresponding figure for attribution of health complaints to MPBS was 31.3%. CONCLUSION: Risk perception of MPBS is strongly associated with general concern, anxiety, depression, and stress, and rather instable over time.......OBJECTIVE: Perception of possible health risks related to mobile phone base stations (MPBS) is an important factor in citizens' opposition against MPBS and is associated with health complaints. The aim of the present study is to assess whether risk perception of MPBS is associated with concerns...

  12. AIS基站短消息特性%Short message characteristics of AIS base stations

    Institute of Scientific and Technical Information of China (English)

    马枫; 初秀民; 严新平

    2012-01-01

    The characteristics of short messages from automatic identification system(AIS) base stations to ships in the inland river and port were studied. The principles of waveform distortion and package error were analyzed when AIS field strength was declined. In the hardware in-the- loop simulation platform, the relationship between message length and package error rate was analyzed, and the prediction model of package error rate was proposed. Combined with Hata- Okumura model, the maximum capacity for short messages sent from AIS base stations to ships was proposed in crowded channel. At last, taking the Shanghai Channel of Huangpu River as an example, using the proposed model, the maximum capacity was calculated and compared with the measured result. Comparison result indicates that the reliability of short message decreases with the increase of short message length and the decrease of fixed field strength. The number of AIS target ships communicating with AIS base stations meanwhile is limited. For the Shanghai Channel of Huangpu River, the calculated number of AIS target ship communicating with an AIS base station is 26 when the total AIS target ships is 625, and the measured value is 24, so the calculated value basically matches with the reality value. 2 tabs, 6 figs, 15 refs.%研究了在内河与港口应用环境下,由船载自动识别系统(AIS)基站发送到船舶的短消息特征,分析了AIS报文在场强下降后的波形失真与误包原理。在半实物仿真平台下,分析了消息长度与误包率的关系,并给出相应的误包率预测模型。结合Hata—Okumura模型,提出了拥挤航道下AIs基站向船舶发送短消息的极限容量。最后以黄浦江上海航道为例,运用极限计算模型对其极限容量进行了预测,并与实测结果进行了对比。对比结果表明:短消息可靠性随长度增加与场强降低而逐步下降,基站能同时进行短消息管理的AIS船舶数量有限,

  13. Microwave radiation safety assessment around mobile telephone base station (MTBS) in Peninsular Malaysia

    International Nuclear Information System (INIS)

    Mobile telephone is one of the fastest popular consumer product introduced in the market. Since more people are using mobile telephone, the number of mobile telephone base station (MTBS) in Malaysia had also increased in order to provide a better coverage services to consumer. The antennas that are required for the mobile (or cellular) telephone network are located at MTBS. This antenna emits radio frequency (RF) and microwave (MW) radiation. Due to the concerns that has been raised by the people that are living or working nearby to MTBS about the possibility of adverse health effects that might occur due to the exposure of this radiation, a project of microwave radiation safety assessment around MTBS by MINT was carried out (September 2003 - January 2006). It was involved with 128 MTBS from three biggest service providers in Malaysia. This assessment is required to establish a baseline data in term of pattern and trend of the radiation emission from the facilities as well as to develop a public confident. In this paper, it will describe the fact that radiation is critical to the MTBS system and without the radiation, the MTBS system is functionless. It will also highlight the result of the assessment's work that has been carried out by MINT around MTBS mounted on the rooftops and towers. The average reading varies between the detection limit of the instrument 2 (2 (7.204 V/m). The highest average reading corresponds to about 2.0% of the Suruhanjaya Komunikasi dan Multimedia Malaysia (MCMC) exposure limit for public. The finding of this measurement confirms that the presence of RF and MW radiation in public accessible area around the base station was very low and comparable to the radiation levels in other places away from MTBS. There is also no evidence, from any laboratory or epidemiology studies that the exposure to RF energy levels recommended limits has any health significance for humans. (Author)

  14. Mesospheric CO above Troll station, Antarctica observed by a ground based microwave radiometer

    Directory of Open Access Journals (Sweden)

    C. Straub

    2013-06-01

    Full Text Available This paper presents mesospheric carbon monoxide (CO data acquired by the ground-based microwave radiometer of the British Antarctic Survey (BAS radiometer stationed at Troll station in Antarctica (72° S, 2.5° E, 1270 m a.s.l.. The dataset covers the period from February 2008 to January 2010, however, due to very low CO concentrations below approximately 80 km altitude in summer, profiles are only presented during the Antarctic winter. CO is measured for approximately 2 h each day and profiles are retrieved approximately every half hour. The retrieved profiles, covering the pressure range from 1 to 0.01 hPa (approximately 48 to 80 km, are compared to measurements from Microwave Limb Sounder on the Aura satellite (Aura/MLS and Whole Atmosphere Community Climate Model with Specified Dynamics (SD-WACCM. This intercomparison reveals a low bias of 0.5 to 1 ppmv at 0.1 hPa (approximately 64 km and 2.5 to 3.5 ppmv at 0.01 hPa (approximately 80 km of the BAS microwave radiometer compared to both reference datasets. One explanation for this low bias could be the known high bias of MLS which is on the same order of magnitude. The ground based radiometer shows high and significant correlation (coefficients higher than 0.9/0.7 compared to MLS/SD-WACCM at all altitudes compared with both reference datasets. The dataset can be accessed under http://dx.doi.org/10/mhq.

  15. Mesospheric CO above Troll station, Antarctica observed by a ground based microwave radiometer

    Directory of Open Access Journals (Sweden)

    C. Straub

    2013-01-01

    Full Text Available This paper presents mesospheric carbon monoxide (CO data acquired by the ground-based microwave radiometer of the British Antarctic Survey (BAS radiometer stationed at Troll station in Antarctica (72° S, 2.5° E, 1270 a.m.s.l.. The data set covers the period from February 2008 to January 2010, however, due to very low CO concentrations below approximately 80 km altitude in summer, profiles can only be retrieved during Antarctic winter. CO is measured for approximately 2 h each day and profiles are retrieved approximately every half hour. The retrieved profiles, covering the pressure range from 1 to 0.01 hPa (approximately 48 to 80 km, are compared to measurements from Aura/MLS and SD-WACCM. This intercomparison reveals a low bias of 0.5 to 1 ppmv at 0.1 hPa (approximately 64 km and 2.5 to 3.5 ppmv at 0.01 hPa (approximately 80 km of the BAS microwave radiometer compared to both reference datasets. One explanation for this low bias could be the known high bias of MLS which is in the same order of magnitude. The ground based radiometer shows high and significant correlation (coefficients higher than 0.9/0.65 compared to MLS/SD-WACCM at all altitudes compared with both reference datasets. doi:10.5285/DE3E2092-406D-47A9-9205-3971A8DFB4A9

  16. Fire Stations - 2007

    Data.gov (United States)

    Kansas Data Access and Support Center — Fire Station Locations in Kansas Any location where fire fighters are stationed at or based out of, or where equipment that such personnel use in carrying out their...

  17. Fire Stations - 2009

    Data.gov (United States)

    Kansas Data Access and Support Center — Fire Stations in Kansas Any location where fire fighters are stationed or based out of, or where equipment that such personnel use in carrying out their jobs is...

  18. Quality assurance and radiofrequency heating

    International Nuclear Information System (INIS)

    One pf the potential problems and limitations of scanning at high field strength is the deposition or radiofrequency (RF) power into the body. This paper proposes an inexpensive means of assessing radiofrequency power deposition in a magnet. This is particularly important at 3T where sequences approach Food and Drug Administration approved RF limits. It will also be of interest to operators at 1.5 T as part of their ongoing quality assurance programs. At 3T, we found that the RF power deposited in the magnet was less than that read by the MR power monitor. All measurements were performed with a 2.51 perspex spherical phantom. Copyright (2002) Blackwell Science Pty Ltd

  19. Performance Analyses of Renewable and Fuel Power Supply Systems for Different Base Station Sites

    Directory of Open Access Journals (Sweden)

    Josip Lorincz

    2014-11-01

    Full Text Available Base station sites (BSSs powered with renewable energy sources have gained the attention of cellular operators during the last few years. This is because such “green” BSSs impose significant reductions in the operational expenditures (OPEX of telecom operators due to the possibility of on-site renewable energy harvesting. In this paper, the green BSSs power supply system parameters detected through remote and centralized real time sensing are presented. An implemented sensing system based on a wireless sensor network enables reliable collection and post-processing analyses of many parameters, such as: total charging/discharging current of power supply system, battery voltage and temperature, wind speed, etc. As an example, yearly sensing results for three different BSS configurations powered by solar and/or wind energy are discussed in terms of renewable energy supply (RES system performance. In the case of powering those BSS with standalone systems based on a fuel generator, the fuel consumption models expressing interdependence among the generator load and fuel consumption are proposed. This has allowed energy-efficiency comparison of the fuel powered and RES systems, which is presented in terms of the OPEX and carbon dioxide (CO2 reductions. Additionally, approaches based on different BSS air-conditioning systems and the on/off regulation of a daily fuel generator activity are proposed and validated in terms of energy and capital expenditure (CAPEX savings.

  20. ANALYSIS OF THE METHOD FOR COMPENSATIVE POWER IN THE ELECTRICITY SUPPLY NETWORKS BASED ON PORTABLE ELECTRIC POWER STATION

    OpenAIRE

    Karamnov, A.

    2006-01-01

    In this paper we consider a base technology for compensating the reactive power in electricity supply networks based on portable electric power stations (e.g. bank of capacitors, synchronous motors, barier-layer statistical reactive power source). Analysis of advantages and disadvantages for considered engineering solutions is performed.

  1. 47 CFR 0.434 - Data bases and lists of authorized broadcast stations and pending broadcast applications.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Data bases and lists of authorized broadcast stations and pending broadcast applications. 0.434 Section 0.434 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL COMMISSION ORGANIZATION General Information Lists Containing Information Compiled by the Commission § 0.434 Data bases...

  2. Radiofrequency Ablation of Hepatic Cysts : Case Report

    International Nuclear Information System (INIS)

    Radiofrequency ablation has been frequently performed on intra-hepatic solid tumor, namely, hepatocellular carcinoma, metastatic tumor and cholangio carcinoma, for take the cure. But, the reports of radiofrequency ablation for intrahepatic simple cysts are few. In vitro experiment of animal and in vivo treatment for intrahepatic cysts of human had been reported in rare cases. We report 4 cases of radiofrequency ablation for symptomatic intrahepatic cysts

  3. Developmental effects induced by chronic and prolonged exposure of chicken embryos to 900 MHz GSM base station radiation

    International Nuclear Information System (INIS)

    Interference from base station radiation with embryonic development was investigated by chronic and prolonged exposure of developing chicken embryos. The latter were exposed under a 900 MHz GSM base station radiating microwaves at recommended safety level, i.e., 41 V/m. Total death rate was 7.7 times higher among radiation exposed embryos (78.5%) than among sham exposures (10.2%). Radiation exposure was associated with delayed hatching (3.2 days) and slightly but significantly increased (P<0.01) weight of hatchings. These finding indicated that base station radiation can induce lethal effect, as well as developmental retardation. They arouse questioning as to the adequacy of current safety guidelines. (author)

  4. Network analysis of geomagnetic substorms using the SuperMAG database of ground-based magnetometer stations

    CERN Document Server

    Dods, J; Gjerloev, J W

    2016-01-01

    The overall morphology and dynamics of magnetospheric substorms is well established in terms of the observed qualitative auroral features seen in ground-based magnetometers. This paper focuses on the quantitative characterization of substorm dynamics captured by ground-based magnetometer stations. We present the first analysis of substorms using dynamical networks obtained from the full available set of ground-based magnetometer observations in the Northern Hemisphere. The stations are connected in the network when the correlation between the vector magnetometer time series from pairs of stations within a running time window exceeds a threshold. Dimensionless parameters can then be obtained that characterize the network and by extension, the spatiotemporal dynamics of the substorm under observation. We analyze four isolated substorm test cases as well as a steady magnetic convection (SMC) event and a day in which no substorms occur. These test case substorms are found to give a consistent characteristic netwo...

  5. Spin exchange optical pumping based polarized {sup 3}He filling station for the Hybrid Spectrometer at the Spallation Neutron Source

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, C. Y.; Tong, X.; Brown, D. R.; Culbertson, H.; Kadron, B.; Robertson, J. L. [Instrument and Source Design Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Graves-Brook, M. K. [Research Accelerator Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Hagen, M. E. [Neutron Data Analysis and Visualization Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Lee, W. T. [Australian Nuclear Science and Technology Organisation, New Illawarra Road, Lucas Heights, NSW 2234 (Australia); Winn, B. [Quantum Condensed Matter Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2013-06-15

    The Hybrid Spectrometer (HYSPEC) is a new direct geometry spectrometer at the Spallation Neutron Source at the Oak Ridge National Laboratory. This instrument is equipped with polarization analysis capability with 60 Degree-Sign horizontal and 15 Degree-Sign vertical detector coverages. In order to provide wide angle polarization analysis for this instrument, we have designed and built a novel polarized {sup 3}He filling station based on the spin exchange optical pumping method. It is designed to supply polarized {sup 3}He gas to HYSPEC as a neutron polarization analyzer. In addition, the station can optimize the {sup 3}He pressure with respect to the scattered neutron energies. The depolarized {sup 3}He gas in the analyzer can be transferred back to the station to be repolarized. We have constructed the prototype filling station. Preliminary tests have been carried out demonstrating the feasibility of the filling station. Here, we report on the design, construction, and the preliminary results of the prototype filling station.

  6. Long-lead station-scale prediction of hydrological droughts in South Korea based on bivariate pattern-based downscaling

    Science.gov (United States)

    Sohn, Soo-Jin; Tam, Chi-Yung

    2015-07-01

    Capturing climatic variations in boreal winter to spring (December-May) is essential for properly predicting droughts in South Korea. This study investigates the variability and predictability of the South Korean climate during this extended season, based on observations from 60 station locations and multi-model ensemble (MME) hindcast experiments (1983/1984-2005/2006) archived at the APEC Climate Center (APCC). Multivariate empirical orthogonal function (EOF) analysis results based on observations show that the first two leading modes of winter-to-spring precipitation and temperature variability, which together account for ~80 % of the total variance, are characterized by regional-scale anomalies covering the whole South Korean territory. These modes were also closely related to some of the recurrent large-scale circulation changes in the northern hemisphere during the same season. Consistent with the above, examination of the standardized precipitation evapotranspiration index (SPEI) indicates that drought conditions in South Korea tend to be accompanied by regional-to-continental-scale circulation anomalies over East Asia to the western north Pacific. Motivated by the aforementioned findings on the spatial-temporal coherence among station-scale precipitation and temperature anomalies, a new bivariate and pattern-based downscaling method was developed. The novelty of this method is that precipitation and temperature data were first filtered using multivariate EOFs to enhance their spatial-temporal coherence, before being linked to large-scale circulation variables using canonical correlation analysis (CCA). To test its applicability and to investigate its related potential predictability, a perfect empirical model was first constructed with observed datasets as predictors. Next, a model output statistics (MOS)-type hybrid dynamical-statistical model was developed, using products from nine one-tier climate models as inputs. It was found that, with model sea

  7. Long-lead station-scale prediction of hydrological droughts in South Korea based on bivariate pattern-based downscaling

    Science.gov (United States)

    Sohn, Soo-Jin; Tam, Chi-Yung

    2016-05-01

    Capturing climatic variations in boreal winter to spring (December-May) is essential for properly predicting droughts in South Korea. This study investigates the variability and predictability of the South Korean climate during this extended season, based on observations from 60 station locations and multi-model ensemble (MME) hindcast experiments (1983/1984-2005/2006) archived at the APEC Climate Center (APCC). Multivariate empirical orthogonal function (EOF) analysis results based on observations show that the first two leading modes of winter-to-spring precipitation and temperature variability, which together account for ~80 % of the total variance, are characterized by regional-scale anomalies covering the whole South Korean territory. These modes were also closely related to some of the recurrent large-scale circulation changes in the northern hemisphere during the same season. Consistent with the above, examination of the standardized precipitation evapotranspiration index (SPEI) indicates that drought conditions in South Korea tend to be accompanied by regional-to-continental-scale circulation anomalies over East Asia to the western north Pacific. Motivated by the aforementioned findings on the spatial-temporal coherence among station-scale precipitation and temperature anomalies, a new bivariate and pattern-based downscaling method was developed. The novelty of this method is that precipitation and temperature data were first filtered using multivariate EOFs to enhance their spatial-temporal coherence, before being linked to large-scale circulation variables using canonical correlation analysis (CCA). To test its applicability and to investigate its related potential predictability, a perfect empirical model was first constructed with observed datasets as predictors. Next, a model output statistics (MOS)-type hybrid dynamical-statistical model was developed, using products from nine one-tier climate models as inputs. It was found that, with model sea

  8. Mutual Authentication Between Base and Subscriber Station Can Improve the Security of IEEE 802.16Wimax Network

    Directory of Open Access Journals (Sweden)

    Mohammad Hossain, Mohammad Zavid Parvez & Mohammad Hamidul Islam

    2011-10-01

    Full Text Available High throughput broadband connection over long distance is greatly demanded in the presentweb application. IEEE 802.16/WiMax technology is one of the latest additions on internetbroadband. When wireless devices are connected to the broadband wireless access, securitycomes on the front line to ensure the communication safe and protected from any kind of attacksor threats. Strong and effective security must be confirmed to make the wireless environmentreliable and risk less. Base station authentication is an important part of WiMax security whichmust be confirmed to make the environment more secure. This paper derived the technique tosecure the environment by confirming the authentication of base station.

  9. Knowledge-based system V and V in the Space Station Freedom program

    International Nuclear Information System (INIS)

    Knowledge Based System (KBSs) are expected to be heavily used in the Space Station Freedom Program (SSFP). Although SSFP Verification and Validation (V and V) requirements are based on the latest state-of-the-practice in software engineering technology, they may be insufficient for Knowledge Based Systems (KBSs); it is widely stated that there are differences in both approach and execution between KBS V and V and conventional software V and V. In order to better understand this issue, the authors have surveyed and/or interviewed developers from sixty expert system projects in order to understand the differences and difficulties in KBS V and V. They have used these survey results to analyze the SSFP V and V requirements for conventional software in order to determine which specific requirements are inappropriate for KBS V and V and why they are inappropriate. Further work will result in a set of recommendations that can be used either as guidelines for applying conventional software V and V requirements to KBSs or as modifications to extend the existing SSFP conventional software V and V requirements to include KBS requirements. The results of this work are significant to many projects, in addition to SSFP, which will involve KBSs

  10. A Dynamic Programming Approach for Base Station Sleeping in Cellular Networks

    Science.gov (United States)

    Gong, Jie; Zhou, Sheng; Niu, Zhisheng

    The energy consumption of the information and communication technology (ICT) industry, which has become a serious problem, is mostly due to the network infrastructure rather than the mobile terminals. In this paper, we focus on reducing the energy consumption of base stations (BSs) by adjusting their working modes (active or sleep). Specifically, the objective is to minimize the energy consumption while satisfying quality of service (QoS, e.g., blocking probability) requirement and, at the same time, avoiding frequent mode switching to reduce signaling and delay overhead. The problem is modeled as a dynamic programming (DP) problem, which is NP-hard in general. Based on cooperation among neighboring BSs, a low-complexity algorithm is proposed to reduce the size of state space as well as that of action space. Simulations demonstrate that, with the proposed algorithm, the active BS pattern well meets the time variation and the non-uniform spatial distribution of system traffic. Moreover, the tradeoff between the energy saving from BS sleeping and the cost of switching is well balanced by the proposed scheme.

  11. Simulation of bidirectional pedestrian flow in transfer station corridor based on multi forces

    Institute of Scientific and Technical Information of China (English)

    周雪梅; 纪翔峰; 黄凰; 杨晓光

    2014-01-01

    A good understanding of pedestrian movement in the transfer corridor is vital for the planning and design of the station, especially for efficiency and safety.A multi-force vector grid model was presented to simulate the movement of bidirectional pedestrian flow based on cellular automata and forces between pedestrians. The model improves rule-based characteristics of cellular automata, details forces between pedestrians and solves pedestrian collisions by a several-step updating method to simulate pedestrian movements. Two general scenarios in corridor were simulated. One is bidirectional pedestrian flow simulation with isolation facility, and the other is bidirectional pedestrian flow simulation without isolation facility, where there exists disturbance in the middle. Through simulation, some facts can be seen that pedestrians in the case with isolation facility have the largest speed and pedestrians in the case without isolation facility have the smallest speed; pedestrians in the case of unidirectional flow have the largest volume and pedestrians in the case of without isolation facility have the smallest volume.

  12. Subjective symptoms reported by people living in the vicinity of cellular phone base stations: A review of the studies

    International Nuclear Information System (INIS)

    The problem of health effects of electromagnetic fields (EMF) emitted by cellular phone base stations evokes much interest in view of the fact that people living in their vicinity are fated to continuous exposure to EMF. None of the studies carried out throughout the world have revealed excessive values of standards adopted by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). A questionnaire was used as a study tool. The results of the questionnaire survey reveal that people living in the vicinity of base stations report various complaints mostly of the circulatory system, but also of sleep disturbances, irritability, depression, blurred vision, concentration difficulties, nausea, lack of appetite, headache and vertigo. The performed studies showed the relationship between the incidence of individual symptoms, the level of exposure, and the distance between a residential area and a base station. This association was observed in both groups of persons, those who linked their complaints with the presence of the base station and those who did not notice such a relation. Further studies, clinical and those based on questionnaires, are needed to explain the background of reported complaints. (author)

  13. Investigations on the sleep quality of electrosensitive residents near base stations unter homely conditions

    International Nuclear Information System (INIS)

    In this study during a total of 214 nights sleep of 200 volunteers was analyzed. The investigated persons suffered from permanent and severe sleep disturbances and were deeply convinced that the environmental radiofrequency electromagnetic fields (RF EMF) caused their problems. The studies used mobile shields to compare the sleep quality with and without shield including a sham shield. For a predominant number the subjective conviction of volunteers that RF EMF pollution was the cause of their sleep disturbance could be falsified. The pooled analysis resulted in statistically significant placebo-effects for subjective sleep parameters. For 18% of volunteers it could be demonstrated that their belief in shielding improved sleep (placebo-effect). The sleep onset behavior of 9% of the volunteers was statistical significantly affected by RF EMF shielding. The investigations did not indicate adverse health effects of RF EMF emissions in general and from mobile telecommunication fields in particular

  14. Statistical analysis of electromagnetic radiation measurements in the vicinity of GSM/UMTS base station installed on buildings in Serbia

    International Nuclear Information System (INIS)

    As a result of dense deployment of public mobile base stations, additional electromagnetic (EM) radiation occurs in the modern human environment. At the same time, public concern about the exposure to EM radiation emitted by such sources has increased. In order to determine the level of radio frequency radiation generated by base stations, extensive EM field strength measurements were carried out for 664 base station locations, from which 276 locations refer to the case of base stations with antenna system installed on buildings. Having in mind the large percentage (42 %) of locations with installations on buildings, as well as the inevitable presence of people in their vicinity, a detailed analysis of this location category was performed. Measurement results showed that the maximum recorded value of total electric field strength has exceeded International Commission on Non-Ionizing Radiation Protection general public exposure reference levels at 2.5 % of locations and Serbian national reference levels at 15.6 % of locations. It should be emphasised that the values exceeding the reference levels were observed only outdoor, while in indoor total electric field strength in no case exceeded the defined reference levels. (authors)

  15. Non-specific physical symptoms in relation to actual and perceived proximity to mobile phone base stations and powerlines.

    NARCIS (Netherlands)

    Baliatsas, C.; Kamp, I. van; Kelfkens, G.; Schipper, M.; Bolte, J.; Yzermans, J.; Lebret, E.

    2011-01-01

    BACKGROUND: Evidence about a possible causal relationship between non-specific physical symptoms (NSPS) and exposure to electromagnetic fields (EMF) emitted by sources such as mobile phone base stations (BS) and powerlines is insufficient. So far little epidemiological research has been published on

  16. Statistical analysis of electromagnetic radiation measurements in the vicinity of GSM/UMTS base station installed on buildings in Serbia.

    Science.gov (United States)

    Koprivica, Mladen; Slavkovic, Vladimir; Neskovic, Natasa; Neskovic, Aleksandar

    2016-03-01

    As a result of dense deployment of public mobile base stations, additional electromagnetic (EM) radiation occurs in the modern human environment. At the same time, public concern about the exposure to EM radiation emitted by such sources has increased. In order to determine the level of radio frequency radiation generated by base stations, extensive EM field strength measurements were carried out for 664 base station locations, from which 276 locations refer to the case of base stations with antenna system installed on buildings. Having in mind the large percentage (42 %) of locations with installations on buildings, as well as the inevitable presence of people in their vicinity, a detailed analysis of this location category was performed. Measurement results showed that the maximum recorded value of total electric field strength has exceeded International Commission on Non-Ionizing Radiation Protection general public exposure reference levels at 2.5 % of locations and Serbian national reference levels at 15.6 % of locations. It should be emphasised that the values exceeding the reference levels were observed only outdoor, while in indoor total electric field strength in no case exceeded the defined reference levels. PMID:26231558

  17. Laparoscopic Radiofrequency Thermal Ablation for Uterine Adenomyosis

    OpenAIRE

    Scarperi, Stefano; Pontrelli, Giovanni; Campana, Colette; Steinkasserer, Martin; Ercoli, Alfredo; Minelli, Luca; Bergamini, Valentino; Ceccaroni, Marcello

    2015-01-01

    Background and Objectives: Symptomatic uterine adenomyosis, unresponsive to medical therapy, is a challenging condition for patients who desire to preserve their uterus. This study was an evaluation of the feasibility and efficacy of laparoscopic radiofrequency thermal ablation of symptomatic nodular uterine adenomyosis. Methods: Fifteen women with symptomatic nodular adenomyosis, who had no plans for pregnancy but declined hysterectomy, underwent radiofrequency thermal ablation. Ultrasonogra...

  18. Public Exposure from Indoor Radiofrequency Radiation in the City of Hebron, West Bank-Palestine.

    Science.gov (United States)

    Lahham, Adnan; Sharabati, Afefeh; ALMasri, Hussien

    2015-08-01

    This work presents the results of measured indoor exposure levels to radiofrequency (RF) radiation emitting sources in one of the major cities in the West Bank-the city of Hebron. Investigated RF emitters include FM, TV broadcasting stations, mobile telephony base stations, cordless phones [Digital Enhanced Cordless Telecommunications (DECT)], and wireless local area networks (WLAN). Measurements of power density were conducted in 343 locations representing different site categories in the city. The maximum total power density found at any location was about 2.3 × 10 W m with a corresponding exposure quotient of about 0.01. This value is well below unity, indicating compliance with the guidelines of the International Commission on Non-ionizing Radiation Protection (ICNIRP). The average total exposure from all RF sources was 0.08 × 10 W m. The relative contributions from different sources to the total exposure in terms of exposure quotient were evaluated and found to be 46% from FM radio, 26% from GSM900, 15% from DECT phones, 9% from WLAN, 3% from unknown sources, and 1% from TV broadcasting. RF sources located outdoors contribute about 73% to the population exposure indoors. PMID:26107432

  19. Radio-frequency low-coherence interferometry.

    Science.gov (United States)

    Fernández-Pousa, Carlos R; Mora, José; Maestre, Haroldo; Corral, Pablo

    2014-06-15

    A method for retrieving low-coherence interferograms, based on the use of a microwave photonics filter, is proposed and demonstrated. The method is equivalent to the double-interferometer technique, with the scanning interferometer replaced by an analog fiber-optics link and the visibility recorded as the amplitude of its radio-frequency (RF) response. As a low-coherence interferometry system, it shows a decrease of resolution induced by the fiber's third-order dispersion (β3). As a displacement sensor, it provides highly linear and slope-scalable readouts of the interferometer's optical path difference in terms of RF, even in the presence of third-order dispersion. In a proof-of-concept experiment, we demonstrate 20-μm displacement readouts using C-band EDFA sources and standard single-mode fiber. PMID:24978555

  20. Optical generation of radio-frequency power

    International Nuclear Information System (INIS)

    An optical technique for high-power radio-frequency (RF) signal generation is described. The technique uses a unique photodetector based on a traveling-wave design driven by an appropriately modulated light source. The traveling-wave photodetector (TWPD) exhibits simultaneously a theoretical quantum efficiency approaching 100 % and a very large electrical bandwidth. Additionally, it is capable of dissipating the high-power levels required for the RF generation technique. The modulated light source is formed by either the beating together of two lasers or by the direct modulation of a light source. A system example is given which predicts RF power levels of 100's of mW's at millimeter wave frequencies with a theoretical ''wall-plug'' efficiency approaching 34%

  1. Service Station Evaluation Problem in Catering Service of High-Speed Railway: A Fuzzy QFD Approach Based on Evidence Theory

    Directory of Open Access Journals (Sweden)

    Xin Wu

    2015-01-01

    Full Text Available Catering Service of High-Speed Railway (CSHR starts at suppliers, includes distribution centers and service stations in cities, and ends at cabinets in high-speed trains. In Distribution System Design (DSD Problem for CSHR, it is critical to evaluate the alternatives of service stations, which is termed as Service Station Evaluation Problem in Catering Service of High-speed Railway (SSEP-CSHR. As a preparation work for DSD, SSEP-CSHR needs to be solved without detailed information and being accompanied with uncertainty. Fuzzy Quality Function Deployment (F-QFD has been given in the literatures to deal with vagueness in Facility Location Evaluation (FLE. However, SSEP-CSHR that includes identifying and evaluating stations requires not only dealing with the vague nature of assessments but also confirming them. Based on evidence theory, this paper introduces the framework to give the truth of proposition “x is A.” Then it is incorporated into a two-phase F-QFD with an approximate reasoning to enable the truth of the decisions to be measured. A case study that refers to 85 alternative stations on Chinese high-speed railway will be carried out to verify the proposed method. Analysis shows that the proposed evaluation method enhances scientific credibility of FLE and allows decision makers to express how much is known.

  2. Field investigation source area ST58 old Quartermaster service station, Eielson Air Force Base, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Liikala, T.L.; Evans, J.C.

    1995-01-01

    Source area ST58 is the site of the old Quartermaster service station at Eielson Air Force Base, Alaska. The source area is one of several Source Evaluation Report sites being investigated by Pacific Northwest Laboratory for the US Air Force as candidates for no further remedial action, interim removal action, or a remedial investigation/feasibility study under a Federal Facilities Agreement. The purpose of this work was to characterize source area ST58 and excavate the most contaminated soils for use in composting treatability studies. A field investigation was conducted to determine the nature and extent of soil contamination. The field investigation entailed a records search; grid node location, surface geophysical, and soil gas surveys; and test pit soil sampling. Soil excavation followed based on the results of the field investigation. The site was backfilled with clean soil. Results from this work indicate close spatial correlation between screening instruments, used during the field investigation and soil excavation, and laboratory analyses. Gasoline was identified as the main subsurface contaminant based on the soil gas surveys and test pit soil sampling. A center of contamination was located near the northcentral portion of the source area, and a center was located in the northwestern comer. The contamination typically occurred near or below a former soil horizon probably as a result of surface spills and leaks from discontinuities and/or breaks in the underground piping. Piping locations were delineated during the surface geophysical surveys and corresponded very well to unscaled drawings of the site. The high subsurface concentrations of gasoline detected in the northwestern comer of the source area probably reflect ground-water contamination and/or possibly floating product.

  3. Radio-frequency power generation

    OpenAIRE

    Carter, Richard G.

    2013-01-01

    This paper reviews the main types of radio-frequency power amplifiers which are, or may be, used for high-power hadron accelerators. It covers tetrodes, inductive output tubes, klystrons and magnetrons with power outputs greater than 10 kW continuous wave or 100 kW pulsed at frequencies from 50 MHz to 30 GHz. Factors affecting the satisfactory operation of amplifiers include cooling, matching and protection circuits are discussed. The paper concludes with a summary of the state of the art for...

  4. Rapid, Sensitive, and Reusable Detection of Glucose by a Robust Radiofrequency Integrated Passive Device Biosensor Chip

    OpenAIRE

    Nam-Young Kim; Kishor Kumar Adhikari; Rajendra Dhakal; Zorigt Chuluunbaatar; Cong Wang; Eun-Soo Kim

    2015-01-01

    Tremendous demands for sensitive and reliable label-free biosensors have stimulated intensive research into developing miniaturized radiofrequency resonators for a wide range of biomedical applications. Here, we report the development of a robust, reusable radiofrequency resonator based integrated passive device biosensor chip fabricated on a gallium arsenide substrate for the detection of glucose in water-glucose solutions and sera. As a result of the highly concentrated electromagnetic ener...

  5. Wind characteristics on the Yucatan Peninsula based on short term data from meteorological stations

    Energy Technology Data Exchange (ETDEWEB)

    Soler-Bientz, Rolando [CREST, Department of Electronic and Electrical Engineering, Loughborough University, LE11 3TU (United Kingdom); Energy Laboratory, Faculty of Engineering, Autonomous University of Yucatan, Merida, Yucatan (Mexico); Watson, Simon [CREST, Department of Electronic and Electrical Engineering, Loughborough University, LE11 3TU (United Kingdom); Infield, David [Institute of Energy and Environment, University of Strathclyde, Glasgow (United Kingdom)

    2010-04-15

    Due to the availability of sparsely populated and flat open terrain, the Yucatan Peninsula located in eastern Mexico is a promising region from the perspective of wind energy development. Study of the diurnal and seasonal wind resource is an important stage in the move towards commercial exploitation of wind power in this Latin American region. An analysis of the characteristics of the wind resource of the Yucatan Peninsula is presented in this paper, based on 10 min averaged wind speed data from nine meteorological stations, between 2000 and 2007. Hourly and monthly patterns of the main environmental parameters have been examined. Highly directional behaviour was identified that reflects the influence of winds coming from the Caribbean Sea and the Gulf of Mexico. The characteristics of the wind speed variation observed at the studied sites reflected their proximity to the coast and whether they were influenced by wind coming predominantly from over the land or predominantly from over the sea. The atmospheric stability over the eastern seas of the Yucatan Peninsula was also analysed to assess thermal effects for different wind directions. The findings were consistent with the variation in average wind speeds observed at the coastal sites where winds came predominantly from over the sea. The research presented here is to be used as a basis for a wind atlas for the Yucatan Peninsula. (author)

  6. The vertical pattern of microwave radiation around BTS (Base Transceiver Station) antennae in Hashtgerd township.

    Science.gov (United States)

    Nasseri, Simin; Monazzam, Mohammadreza; Beheshti, Meisam; Zare, Sajad; Mahvi, Amirhosein

    2013-01-01

    New environmental pollutants interfere with the environment and human life along with technology development. One of these pollutants is electromagnetic field. This study determines the vertical microwave radiation pattern of different types of Base Transceiver Station (BTS) antennae in the Hashtgerd city as the capital of Savojbolagh County, Alborz Province of Iran. The basic data including the geographical location of the BTS antennae in the city, brand, operator type, installation and its height was collected from radio communication office, and then the measurements were carried out according to IEEE STD 95. 1 by the SPECTRAN 4060. The statistical analyses were carried out by SPSS16 using Kolmogorov Smirnov test and multiple regression method. Results indicated that in both operators of Irancell and Hamrah-e-Aval (First Operator), the power density rose with an increase in measurement height or decrease in the vertical distance of broadcaster antenna. With mix model test, a significant statistical relationship was observed between measurement height and the average power density in both types of the operators. With increasing measuring height, power density increased in both operators. The study showed installing antennae in a crowded area needs more care because of higher radiation emission. More rigid surfaces and mobile users are two important factors in crowded area that can increase wave density and hence raise public microwave exposure. PMID:24359870

  7. On the feasibility of superjunction thick-SOI power LDMOS transistors for RF base station applications

    Science.gov (United States)

    Cortes, I.; Roig, J.; Flores, D.; Hidalgo, S.; Rebollo, J.

    2007-02-01

    The feasibility of applying the superjunction (SJ) concept to a thick-SOI LDMOS transistor for base station applications is studied in this paper. An extensive comparison with conventional RF LDMOS structures is performed in terms of breakdown voltage (VBR) versus drift resistance (Rdr) values. Unlike conventional LDMOS structures, the Rdr value in SJ LDMOS structures not only depends on the doping concentration but especially on the characteristics of P and N pillars. The charge compensation due to inter-diffusion between adjacent pillars is responsible for the observed Rdr increase. In order to accomplish an optimum pillar formation with the minimum possible transition between P and N pillars with inherent net doping reduction, high energy multi-implantations and a small thermal budget must be used. Moreover, the distance between P and N pillar implantation windows must be properly set to alleviate the doping inter-diffusion effect. The VBR/Rdr ratio value is a good indicator to evaluate the SJ LDMOS feasibility for RF applications.

  8. What input data are needed to accurately model electromagnetic fields from mobile phone base stations?

    Science.gov (United States)

    Beekhuizen, Johan; Kromhout, Hans; Bürgi, Alfred; Huss, Anke; Vermeulen, Roel

    2015-01-01

    The increase in mobile communication technology has led to concern about potential health effects of radio frequency electromagnetic fields (RF-EMFs) from mobile phone base stations. Different RF-EMF prediction models have been applied to assess population exposure to RF-EMF. Our study examines what input data are needed to accurately model RF-EMF, as detailed data are not always available for epidemiological studies. We used NISMap, a 3D radio wave propagation model, to test models with various levels of detail in building and antenna input data. The model outcomes were compared with outdoor measurements taken in Amsterdam, the Netherlands. Results showed good agreement between modelled and measured RF-EMF when 3D building data and basic antenna information (location, height, frequency and direction) were used: Spearman correlations were >0.6. Model performance was not sensitive to changes in building damping parameters. Antenna-specific information about down-tilt, type and output power did not significantly improve model performance compared with using average down-tilt and power values, or assuming one standard antenna type. We conclude that 3D radio wave propagation modelling is a feasible approach to predict outdoor RF-EMF levels for ranking exposure levels in epidemiological studies, when 3D building data and information on the antenna height, frequency, location and direction are available. PMID:24472756

  9. Soyuz-TM-based interim Assured Crew Return Vehicle (ACRV) for the Space Station Freedom

    Science.gov (United States)

    Semenov, Yu. P.; Babkov, Oleg I.; Timchenko, Vladimir A.; Craig, Jerry W.

    1993-01-01

    The concept of using the available Soyuz-TM Assured Crew Return Vehicle (ACRV) spacecraft for the assurance of the safety of the Space Station Freedom (SSF) crew after the departure of the Space Shuttle from SSF was proposed by the NPO Energia and was accepted by NASA in 1992. The ACRV will provide the crew with the capability to evacuate a seriously injured/ill crewmember from the SSF to a ground-based care facility under medically tolerable conditions and with the capability for a safe evacuation from SSF in the events SSF becomes uninhabitable or the Space Shuttle flights are interrupted for a time that exceeds SSF ability for crew support and/or safe operations. This paper presents the main results of studies on Phase A (including studies on the service life of ACRV; spacecraft design and operations; prelaunch processing; mission support; safety, reliability, maintenance and quality and assurance; landing, and search/rescue operations; interfaces with the SSF and with Space Shuttle; crew accommodation; motion of orbital an service modules; and ACRV injection by the Expendable Launch Vehicles), along with the objectives of further work on the Phase B.

  10. Spherical Projection Based Straight Line Segment Extraction for Single Station Terrestrial Laser Point Cloud

    Directory of Open Access Journals (Sweden)

    ZHANG Fan

    2015-06-01

    Full Text Available Due to the discrete distribution computing errors and lack of adaptability are ubiquitous in the current straight line extraction for TLS data methods. A 3D straight line segment extraction method is proposed based on spherical projection for single station terrestrial laser point clouds. Firstly, horizontal and vertical angles of each laser point are calculated by means of spherical coordinates, intensity panoramic image according to the two angles is generated. Secondly, edges which include straight line features are detected from intensity panoramic image by using of edge detection algorithm. Thirdly, great circles are detected from edges of panoramic image using spherical Hough transform. According to the axiom that a straight line segment in 3D space is a spherical great circle after spherical projection, detecting great circles from spherical projected data sets is essentially detecting straight line segments from 3D data sets without spherical projection. Finally, a robust 3D straight line fitting method is employed to fitting the straight lines and calculating parameters of the straight line segments. Experiments using different data sets and comparison with other methods show the accuracy and applicability of the proposed method.

  11. A web-based tool that combines satellite and weather station observations to support irrigation scheduling

    Science.gov (United States)

    Abstract: The Satellite Irrigation Management Support (SIMS) project combines NASA's Terrestrial Observation and Prediction System (TOPS), Landsat and MODIS satellite imagery, and reference evapotranspiration from surface weather station networks to map daily crop irrigation demand in California in ...

  12. A case-based reasoning approach for estimating the costs of pump station projects

    OpenAIRE

    Marzouk, Mohamed M.; Rasha M. Ahmed

    2011-01-01

    The effective estimation of costs is crucial to the success of construction projects. Cost estimates are used to evaluate, approve and/or fund projects. Organizations use some form of classification system to identify the various types of estimates that may be prepared during the lifecycle of a project. This research presents a parametric-cost model for pump station projects. Fourteen factors have been identified as important to the influence of the cost of pump station projects. A data set t...

  13. Radiofrequency ablation of high-grade dysplastic nodules in chronic liver disease: comparison with well-differentiated hepatocellular carcinoma based on long-term results

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seong Hyun; Lim, Hyo K.; Kim, Min Ju; Choi, Dongil; Rhim, Hyunchul [Sungkyunkwan University School of Medicine, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Seoul (Korea); Park, Cheol Keun [Sungkyunkwan University School of Medicine, Department of Pathology, Samsung Medical Center, Seoul (Korea)

    2008-04-15

    This retrospective study compared the long-term results of percutaneous radiofrequency (RF) ablation for high-grade dysplastic nodules (DNs) and well-differentiated hepatocellular carcinomas (HCCs). Between April 1999 and December 2006, 20 patients with 21 high-grade DNs (range, 1.2-3.0 cm; mean, 1.9 cm) (group 1) and 49 with a well-differentiated HCC (range, 1.0-5.0 cm; mean, 2.3 cm) (group 2) underwent RF ablation. The technique effectiveness, local tumor progression, cancer-free and cumulative survivals using the Kaplan-Meier method were compared. The technique effectiveness rates at 1 year after RF ablation were 100% (19/19) and 94.1% (32/34) in groups 1 and 2, respectively (P > 0.05). The local tumor progression rates in groups 1 and 2 were 0% and 20.6% (7/34), respectively (P = 0.041). The local tumor progression in group 2 was seen on follow-up computed tomography 4-58 months (mean, 17 months) after RF ablation. The 1-, 3-, and 5-year cancer-free survival rates in groups 1 and 2 were 95.0% and 76.9%, 56.2% and 44.6%, and 38.5% and 24.8%, respectively (P > 0.05). The 1-, 3-, and 5-year cumulative survival rates in groups 1 and 2 were 100% and 97.9%, 73.0% and 68.0%, and 63.8% and 51.1%, respectively (P > 0.05). Percutaneous RF ablation is effective for treating high-grade DNs and well-differentiated HCCs. The long-term results after RF ablation of high-grade DNs may be improved compared with those of well-differentiated HCCs. (orig.)

  14. Sampling based uncertainty analysis of station blackout in PSB VVER integral test facility

    International Nuclear Information System (INIS)

    Highlights: → SBO analysis in PSB VVER ITF has been carried out using RELAP5/MOD3.2. → Uncertainty and sensitivity analysis is carried out with sampling based approach (LHS). → Experimental/code calculated values are within the uncertainty band. → Linear regression analysis is carried out to get order of importance of input parameters. → This methodology can be used for transients of NPP with any best estimate system code. - Abstract: Best estimate accident analysis with uncertainty evaluation is being encouraged in the present licensing scenarios of nuclear power plants. This paper deals with uncertainty and sensitivity analysis for station blackout in PSB VVER integral test facility under the framework of coordinated research project of IAEA. Nodalization was developed using best estimate system code RELAP5/MOD3.2 and its steady state and transient level qualifications are achieved. Sampling based approaches are used to carry out uncertainty and sensitivity/importance analysis. The objective of the analysis is to get confidence for uncertainty methodology by comparing with the experimental results and extend its applicability to NPPs. Uncertainty analysis is carried out by selecting nine important input parameters with specified ranges and its uniform distributions. A design matrix of 45 x 9 is generated for variations of input parameters with the Latin Hypercube Sampling and 45 code runs were taken. Linear regression was also carried out to quantify the effect of each individual input parameter on output parameters in terms of standard rank regression coefficients. Uncertainty band in output parameters is defined between 95th and 5th percentile value. It is observed that most of the experimental values and code calculated reference values are lying within the uncertainty band. For most of the parameters, width of uncertainty band increases with transient progression time.

  15. Band-selective radiofrequency pulses

    Science.gov (United States)

    Geen, Helen; Freeman, Ray

    A theoretical treatment is given of the general problem of designing amplitude-modulated radiofrequency pulses that will excite a specified band of frequencies within a high-resolution NMR spectrum with uniform intensity and phase but with negligible excitation elsewhere. First a trial pulse envelope is defined in terms of a finite Fourier series and its frequency-domain profile calculated through the Bloch equations. The result is compared with the desired target profile to give a multidimensional error surface. The method of simulated annealing is then used to find the global minimum on this surface and the result refined by standard gradient-descent optimization. In this manner, a family of new shaped radio-frequency pulses, known as BURP ( band-selective, uniform response, pure-phase) pulses, has been created. These are of two classes—pulses that excite or invert z magnetization and those that act as general-rotation πr/2 or π pulses irrespective of the initial condition of the nuclear magnetization. It was found convenient to design the latter class as amplitude-modulated time-symmetric pulses. Tables of Fourier coefficients and pulse-shape ordinates are given for practical implementation of BURP pulses, together with the calculated frequency-domain responses and experimental verifications. Examples of the application of band-selective pulses in conventional and multidimensional spectroscopy are given. Pure-phase pulses of this type should also find applications in magnetic resonance imaging where refocusing schemes are undesirable.

  16. Space Station Freedom (SSF) Data Management System (DMS) performance model data base

    Science.gov (United States)

    Stovall, John R.

    1993-01-01

    The purpose of this document was originally to be a working document summarizing Space Station Freedom (SSF) Data Management System (DMS) hardware and software design, configuration, performance and estimated loading data from a myriad of source documents such that the parameters provided could be used to build a dynamic performance model of the DMS. The document is published at this time as a close-out of the DMS performance modeling effort resulting from the Clinton Administration mandated Space Station Redesign. The DMS as documented in this report is no longer a part of the redesigned Space Station. The performance modeling effort was a joint undertaking between the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) Flight Data Systems Division (FDSD) and the NASA Ames Research Center (ARC) Spacecraft Data Systems Research Branch. The scope of this document is limited to the DMS core network through the Man Tended Configuration (MTC) as it existed prior to the 1993 Clinton Administration mandated Space Station Redesign. Data is provided for the Standard Data Processors (SDP's), Multiplexer/Demultiplexers (MDM's) and Mass Storage Units (MSU's). Planned future releases would have added the additional hardware and software descriptions needed to describe the complete DMS. Performance and loading data through the Permanent Manned Configuration (PMC) was to have been included as it became available. No future releases of this document are presently planned pending completion of the present Space Station Redesign activities and task reassessment.

  17. A geomorphology-based ANFIS model for multi-station modeling of rainfall-runoff process

    Science.gov (United States)

    Nourani, Vahid; Komasi, Mehdi

    2013-05-01

    This paper demonstrates the potential use of Artificial Intelligence (AI) techniques for predicting daily runoff at multiple gauging stations. Uncertainty and complexity of the rainfall-runoff process due to its variability in space and time in one hand and lack of historical data on the other hand, cause difficulties in the spatiotemporal modeling of the process. In this paper, an Integrated Geomorphological Adaptive Neuro-Fuzzy Inference System (IGANFIS) model conjugated with C-means clustering algorithm was used for rainfall-runoff modeling at multiple stations of the Eel River watershed, California. The proposed model could be used for predicting runoff in the stations with lack of data or any sub-basin within the watershed because of employing the spatial and temporal variables of the sub-basins as the model inputs. This ability of the integrated model for spatiotemporal modeling of the process was examined through the cross validation technique for a station. In this way, different ANFIS structures were trained using Sugeno algorithm in order to estimate daily discharge values at different stations. In order to improve the model efficiency, the input data were then classified into some clusters by the means of fuzzy C-means (FCMs) method. The goodness-of-fit measures support the gainful use of the IGANFIS and FCM methods in spatiotemporal modeling of hydrological processes.

  18. Metamaterials for Wireless Communications, Radiofrequency Identification, and Sensors

    OpenAIRE

    Ferran Martín

    2012-01-01

    This paper is focused on the application of concepts derived from metamaterials to the development of novel devices, circuits, and antennas of interest in wireless communications, radiofrequency identification (RFID), and sensors. Specifically, it is shown that artificial transmission lines based (or inspired) on metamaterials exhibit interesting properties, useful for the implementation of high-performance and compact devices as well as novel functional devices. Thanks to the presence of rea...

  19. Electromagnetic induction imaging with a radio-frequency atomic magnetometer

    OpenAIRE

    Deans, C.; Marmugi, L.; Hussain, S.; Renzoni, F.

    2016-01-01

    We report on a compact, tunable, and scalable to large arrays imaging device, based on a radio-frequency optically pumped atomic magnetometer operating in magnetic induction tomography modality. Imaging of conductive objects is performed at room temperature, in an unshielded environment and without background subtraction. Conductivity maps of target objects exhibit not only excellent performance in terms of shape reconstruction but also demonstrate detection of sub-millimetric cracks and pene...

  20. Successful Treatment of Erythematotelangiectatic Rosacea with Pulsed Light and Radiofrequency

    OpenAIRE

    Taub, Amy Forman; DeVita, Erin C.

    2008-01-01

    Introduction: Many laser and light devices have reported to be successful in the treatment of the flushing, background erythema, and telangiectasias that characterize erythematotelangiectatic rosacea including pulsed dye laser, potassium titanyl phosphate, intense pulsed light, and dual-wavelength lasers. A technology called ELOS (electro-optical synergy) combines pulsed light or laser with bipolar radiofrequency. This combination, developed in 2000, was based on the premise that these two fo...

  1. Current status of radiofrequency ablation of hepatocellular carcinoma

    OpenAIRE

    Rhim, Hyunchul; Lim, Hyo K.; Choi, Dongil

    2010-01-01

    Loco-regional treatments for hepatocellular carcinoma (HCC) are important alternatives to curative transplantation or resection. Among them, radiofrequency ablation (RFA) is accepted as the most popular technique showing excellent local tumor control and acceptable morbidity. The current role of RFA is well documented in the evidence-based practice guidelines of European Association of Study of Liver, American Association of Study of the Liver Disease and Japanese academic societies. Several ...

  2. Knowledge-based decision support for Space Station assembly sequence planning

    Science.gov (United States)

    1991-04-01

    A complete Personal Analysis Assistant (PAA) for Space Station Freedom (SSF) assembly sequence planning consists of three software components: the system infrastructure, intra-flight value added, and inter-flight value added. The system infrastructure is the substrate on which software elements providing inter-flight and intra-flight value-added functionality are built. It provides the capability for building representations of assembly sequence plans and specification of constraints and analysis options. Intra-flight value-added provides functionality that will, given the manifest for each flight, define cargo elements, place them in the National Space Transportation System (NSTS) cargo bay, compute performance measure values, and identify violated constraints. Inter-flight value-added provides functionality that will, given major milestone dates and capability requirements, determine the number and dates of required flights and develop a manifest for each flight. The current project is Phase 1 of a projected two phase program and delivers the system infrastructure. Intra- and inter-flight value-added were to be developed in Phase 2, which has not been funded. Based on experience derived from hundreds of projects conducted over the past seven years, ISX developed an Intelligent Systems Engineering (ISE) methodology that combines the methods of systems engineering and knowledge engineering to meet the special systems development requirements posed by intelligent systems, systems that blend artificial intelligence and other advanced technologies with more conventional computing technologies. The ISE methodology defines a phased program process that begins with an application assessment designed to provide a preliminary determination of the relative technical risks and payoffs associated with a potential application, and then moves through requirements analysis, system design, and development.

  3. Estimation Algorithm of Contending Stations Based on Improved DCF Model in IEEE 802.11

    Institute of Scientific and Technical Information of China (English)

    HU He-fei; LIU Yuan-an; LI Shu-lan

    2004-01-01

    The fundamental access method of IEEE 802.11 is a DCF known as carrier sense multiple access with collision avoidance (CSMA/CA) scheme with exponential back-off. RTS_threshold is used to determine whether to deploy RTS/CTS access method. This threshold should vary with the number of contending stations which contend wireless media to get better throughput. The paper proposes an algorithm which estimates the number of contending stations in BSS. The algorithm is shown to be accurate which is verified by elaborate simulations.

  4. Ground-based gamma-ray telescopes as ground stations in deep-space lasercom

    CERN Document Server

    Carrasco-Casado, Alberto; Vergaz, Ricardo

    2016-01-01

    As the amount of information to be transmitted from deep-space rapidly increases, the radiofrequency technology has become a bottleneck in space communications. RF is already limiting the scientific outcome of deep-space missions and could be a significant obstacle in the developing of manned missions. Lasercom holds the promise to solve this problem, as it will considerably increase the data rate while decreasing the energy, mass and volume of onboard communication systems. In RF deep-space communications, where the received power is the main limitation, the traditional approach to boost the data throughput has been increasing the receiver's aperture, e.g. the 70-m antennas in the NASA's Deep Space Network. Optical communications also can benefit from this strategy, thus 10-m class telescopes have typically been suggested to support future deep-space links. However, the cost of big telescopes increase exponentially with their aperture, and new ideas are needed to optimize this ratio. Here, the use of ground-...

  5. Non-specific physical symptoms in relation to actual and perceived proximity to mobile phone base stations and powerlines

    Directory of Open Access Journals (Sweden)

    Bolte John

    2011-06-01

    Full Text Available Abstract Background Evidence about a possible causal relationship between non-specific physical symptoms (NSPS and exposure to electromagnetic fields (EMF emitted by sources such as mobile phone base stations (BS and powerlines is insufficient. So far little epidemiological research has been published on the contribution of psychological components to the occurrence of EMF-related NSPS. The prior objective of the current study is to explore the relative importance of actual and perceived proximity to base stations and psychological components as determinants of NSPS, adjusting for demographic, residency and area characteristics. Methods Analysis was performed on data obtained in a cross-sectional study on environment and health in 2006 in the Netherlands. In the current study, 3611 adult respondents (response rate: 37% in twenty-two Dutch residential areas completed a questionnaire. Self-reported instruments included a symptom checklist and assessment of environmental and psychological characteristics. The computation of the distance between household addresses and location of base stations and powerlines was based on geo-coding. Multilevel regression models were used to test the hypotheses regarding the determinants related to the occurrence of NSPS. Results After adjustment for demographic and residential characteristics, analyses yielded a number of statistically significant associations: Increased report of NSPS was predominantly predicted by higher levels of self-reported environmental sensitivity; perceived proximity to base stations and powerlines, lower perceived control and increased avoidance (coping behavior were also associated with NSPS. A trend towards a moderator effect of perceived environmental sensitivity on the relation between perceived proximity to BS and NSPS was verified (p = 0.055. There was no significant association between symptom occurrence and actual distance to BS or powerlines. Conclusions Perceived proximity to BS

  6. Novel high-resolution temperature probe for radiofrequency dosimetry

    International Nuclear Information System (INIS)

    A novel integrated thermistor probe for temperature evaluations in radiofrequency-heated environments was realized. The probe's sensitive area is based on a highly resistive 50 μm x 100 μm layer of amorphous germanium processed on a glass tip. The small dimensions allow measurements with a distance as close as 150 μm from solid boundaries. Due to its high temperature resolution of 4 mK and its short response time of the order of 10 ms, the sensor is very well suited for dosimetric measurements in strong absorption gradients. The influence of radiofrequency (RF) electric fields on the signal is minimized due to the high resistance of the sensor and the leads. The probe was successfully used to determine the highly nonuniform absorption distribution resulting from the RF exposure of cell cultures placed in Petri dishes. (note)

  7. Minimization of green house gases emission by using hybrid energy system for telephony base station site application

    International Nuclear Information System (INIS)

    Cellular mobile service is a rapidly expanding and a very competitive business worldwide, including developing countries. This paper proposes that the suitable alternative solution of grid power is the stand-alone PV/wind hybrid energy system with diesel generator as a backup for cellular mobile telephony base station site in isolated areas. It is expected that the newly developed and installed system would provide very good opportunities for mobile telephony base station in near future. In addition, protecting the environment and combating climate change are two of the most pressing challenges facing humankind. As energy prices soar, network operators are increasingly scrutinizing their environmental and social responsibilities. This system will be more cost effective and environmental friendly over the conventional diesel generator. Approximately 70-80% fuel cost over conventional diesel generator and the emission of CO2 and other harmful gasses in environments were reduced. (author)

  8. Spaceborne computer executive routine functional design specification. Volume 2: Computer executive design for space station/base

    Science.gov (United States)

    Kennedy, J. R.; Fitzpatrick, W. S.

    1971-01-01

    The computer executive functional system design concepts derived from study of the Space Station/Base are presented. Information Management System hardware configuration as directly influencing the executive design is reviewed. The hardware configuration and generic executive design requirements are considered in detail in a previous report (System Configuration and Executive Requirements Specifications for Reusable Shuttle and Space Station/Base, 9/25/70). This report defines basic system primitives and delineates processes and process control. Supervisor states are considered for describing basic multiprogramming and multiprocessing systems. A high-level computer executive including control of scheduling, allocation of resources, system interactions, and real-time supervisory functions is defined. The description is oriented to provide a baseline for a functional simulation of the computer executive system.

  9. A PC based time domain reflectometer for space station cable fault isolation

    Science.gov (United States)

    Pham, Michael; McClean, Marty; Hossain, Sabbir; Vo, Peter; Kouns, Ken

    1994-01-01

    Significant problems are faced by astronauts on orbit in the Space Station when trying to locate electrical faults in multi-segment avionics and communication cables. These problems necessitate the development of an automated portable device that will detect and locate cable faults using the pulse-echo technique known as Time Domain Reflectometry. A breadboard time domain reflectometer (TDR) circuit board was designed and developed at the NASA-JSC. The TDR board works in conjunction with a GRiD lap-top computer to automate the fault detection and isolation process. A software program was written to automatically display the nature and location of any possible faults. The breadboard system can isolate open circuit and short circuit faults within two feet in a typical space station cable configuration. Follow-on efforts planned for 1994 will produce a compact, portable prototype Space Station TDR capable of automated switching in multi-conductor cables for high fidelity evaluation. This device has many possible commercial applications, including commercial and military aircraft avionics, cable TV, telephone, communication, information and computer network systems. This paper describes the principle of time domain reflectometry and the methodology for on-orbit avionics utility distribution system repair, utilizing the newly developed device called the Space Station Time Domain Reflectometer (SSTDR).

  10. Development of a HTS transceiver sub-system for 3G mobile communication TD-SCDMA base station

    International Nuclear Information System (INIS)

    A prototype of a high temperature superconducting (HTS) transceiver sub-system for applications in a TD-SCDMA, one of the third generation (3G) communication standards, base station has been developed. Both the HTS sub-system and the conventional counterpart have been implemented into a TD-SCDMA commercial communication network and comparison test studies were carried out. The measured results showed that the HTS sub-system could remarkably improve the RF performance of both transmitting and receiving chains.

  11. An InfoStation-based multi-agent system supporting contextualised and personalised mLearning service delivery

    OpenAIRE

    Meere, Damien

    2012-01-01

    peer-reviewed The main work reported in this thesis is the proposition, design and implementation of a novel InfoStation-based multi-agent system, which facilitates the delivery of contextualised and personalised mobile eLearning (mLearning) services, to supplement the traditional educational experience. In support of refining the motivation for this initiative a comprehensive investigation into the evolution, status, characteristics and attributes of technology enhanced lea...

  12. Context-Aware Scheduling of Joint Millimeter Wave and Microwave Resources for Dual-Mode Base Stations

    OpenAIRE

    Semiari, Omid; Saad, Walid; Bennis, Mehdi

    2016-01-01

    One of the most promising approaches to overcome the drastic channel variations of millimeter wave (mmW) communications is to deploy dual-mode base stations that integrate both mmW and microwave (\\muW) frequencies. Reaping the benefits of a dual-mode operation requires scheduling mechanisms that can allocate resources efficiently and jointly at both frequency bands. In this paper, a novel resource allocation framework is proposed that exploits users' context, in terms of user application (UA)...

  13. Feedback control system for soft X-ray magnetic circular dichroism experimental station based on LabVIEW

    International Nuclear Information System (INIS)

    A feedback control system was developed for soft X-ray magnetic circular dichroism experimental station based on LabVIEW. By implementing the system, the stability of current through the sample was improved to provide a good criterion for absorption spectrum analysis. The friendly user interface, flexible interface instruction and strong data storage function are also important for National Synchrotron Radiation Laboratory which is open to users from all over the country. (authors)

  14. Mutual Authentication Between Base and Subscriber Station Can Improve the Security of IEEE 802.16Wimax Network

    OpenAIRE

    Mohammad Hossain, Mohammad Zavid Parvez & Mohammad Hamidul Islam

    2011-01-01

    High throughput broadband connection over long distance is greatly demanded in the presentweb application. IEEE 802.16/WiMax technology is one of the latest additions on internetbroadband. When wireless devices are connected to the broadband wireless access, securitycomes on the front line to ensure the communication safe and protected from any kind of attacksor threats. Strong and effective security must be confirmed to make the wireless environmentreliable and risk less. Base station authen...

  15. Combinatorial Optimization Method for Operation of Pumping Station with Adjustable Blade and Variable Speed Based on Experimental Optimization of Subsystem

    OpenAIRE

    Yi Gong; Jilin Cheng

    2014-01-01

    A decomposition-dynamic programming aggregation method based on experimental optimization for subsystem was proposed to solve mathematical model of optimal operation for single pumping station with adjustable blade and variable speed. Taking minimal daily electric cost as objective function and water quantity pumped by units as coordinated variable, this model was decomposed into several submodels of daily optimal operation with adjustable blade and variable speed for single pump unit which w...

  16. Besar Frekuensi Gelombang Elektromagnetik Dari Base Transceiver Station (Bts) Dan Gejala Hipersensitifitas Di Kelurahan Padang Bulan Medan Tahun 2012

    OpenAIRE

    Nst, Fatiyah Tul Khoir

    2015-01-01

    Phone as communication equipment require electromagnetic wave to perform it’s function, making effect in the growing of Base Transceiver Station (BTS) which produces increasing of electromagnetic wave. Electromagnetic wave give effect the production of melatonin hormone which produced by the pineal gland, the result of it is hypersensitivity complaints, namely headache, disturbance of sleep, disturbance of concentration, constant fatigue, muscle pain and nausea. The purpose of this study ...

  17. RADIASI DI SEKITAR MENARA BASE TRANSCEIVER STATION DI BANDUNG DAN JAKARTA

    Directory of Open Access Journals (Sweden)

    Athena Athena

    2014-02-01

    umum radiasi di sekitar BTS  telah  melampaui  masih  di  bawah  nilai  yang  direkomendasikan  oleh  WHO  dan  ITU  maupun  Keputusan  Ditjen Parpostel tahun 2007, tetapi di beberapa titik pengukuran telah melampaui nilai yang direkomendasikan oleh peraturan tersebut.   Mengingat  efek  yang  ditimbulkan  oleh  pajanan  radiasi  ini  bersifat  kronis,  maka  perlu  adanya  pemantauan besaran radiasi maupun kondisi kesehatan masyarakat di sekitar BTS.Kata Kunci: Menara telepon seluler, radiasi, medan elektromagnetikAbstractResearch of Health Effect of Electromagnetic Fields to People around the Base Transceiver Station (BTS in Jakarta and Bandung.  The aim of the  research is to study the health effects of  BTS existence and BTS radiation exposure to the community who lives near the stations.  The research design  was  cross-sectional  with the number of samples in each location was 10 (7  BTSs with GSM system and 3 BTSs with CDMA system. The samples were chosen purposively. Data collection was performed by measuring the power density in 16 points with a radius of 100 meters around the BTS (every  22,5o angle. According to these measurement results, a further measurement was performed for every 50, 150,200, and 300 meters in the direction where the largest power density was found. The measuring tool used was  Radio Frequency  Electromagnetic  Field  Strength  Meters  SPECTRAN®  HF-2025E.  Afterwards, electromagnetic  field measurement  data  was  mapped  based  on  the  measurement  points  in  each  BTS  and  compared  with  the  existingregulations.  Result:  At  a  distance  of  100  meters  from  BTS,  the  power  density  of  900  MHz  wave  was  ranged  from undetected to 396  W/cm2 with a modus value of 2  W/cm2. For the 1800 MHz wave, the power density was ranged from undetected to 282  W/cm2 with a modus value of 0,4  W/cm2. Meanwhile, the 2200 MHz wave was found to

  18. Relative Response of Electric Field Probes to Pulsed Radiofrequency Radiation – Preliminary Results

    International Nuclear Information System (INIS)

    Pulsed Radiofrequency Radiation (RFR) is emitted by many apparatuses such as cellular GSM base stations, radars and avionics systems. According to major safety standards, such as ICNIRP 1998, assessment of human exposure to pulsed RFR requires the evaluation of both peak and average electric field amplitudes. Since there is no practical way of measuring the peak field, one can rely on average field measurements, and calculate the peak field by dividing the average field by the RFR duty cycle. RFR safety measurements are usually performed with wideband electric field meters. Two major kinds of electric field probes (EFP) are commercially available for these meters, based on two different physical principles. Thermocouple based devices are designated to measure the field true RMS, regardless of the pulse shape. However, thermocouple probes have many disadvantages (i.e. high susceptibility to ambient temperature, vulnerability to high fields, limited sensitivity and narrow dynamic range); therefore they are not commonly used. As opposed to thermocouples, diode probes are much less vulnerable to these disadvantages. Thus, these probes are used for most commercial electric field meters and safety measurements. Consequently, diode probes which are known to be not suitable for pulsed RFR measurements are practically used in most cases. Hence, we find it essential to assess the response of commercial EFP to pulsed RFR. In a series of experiments, we exposed EFPs to pulsed RFR and examined their response under different pulse parameters

  19. Protective role of sesame oil against mobile base station-induced oxidative stress

    Directory of Open Access Journals (Sweden)

    Ebtisam A. Marzook

    2014-01-01

    Full Text Available The present study was undertaken to shed the light on the environmental threats associated with the wireless revolution and the health hazards associated with exposure to mobile base station (MBS. Besides, studying the possible protective role of sesame oil (SO as an antioxidant against oxidative stress. Therefore, the present work was designed to study the effect of chronic exposure to electromagnetic radiations (EMR, produced by a cellular tower for mobile phone and the possible protective role of sesame oil on glutathione reductase (GSH-Rx, superoxide dismutase (SOD, catalase (CAT, total testosterone and lipid profile (total cholesterol (Tch, triglycerides (TG, low density lipoprotein cholesterol (LDL-c and high density lipoprotein cholesterol (HDL-c in male albino rats. Rats were arranged into four groups: the control unexposed, the exposed untreated and the exposed treated groups (1.5 and 3 ml oil. Exposed groups were subjected to electromagnetic field at frequency of 900 MHz, for 24 h/day for 8 weeks, at the same time both treated groups were supplied with oral injection of sesame oil three times per week. At the end of the experiment, blood samples were obtained for determination of the above mentioned variables in serum. The results obtained revealed that TG and testosterone were raised significantly over control in all groups and the significant increase in oil groups occurred in dose dependent manner. SOD and CAT activities were reduced significantly in exposed rats than control and increased significantly in sesame oil groups as the dose of oil increased. Total cholesterol only showed remarkable reduction in the group treated with 3 ml sesame oil. Also, in this latter group, significant elevation of GSH-Rx was recorded. Changes in serum HDL-c and LDL-c followed an opposite trend in exposed and sesame oil groups reflecting their affectation by EMR or sesame oil. In conclusion, all results of the current study proved that sesame oil

  20. Phenology model from weather station meteorology does not predict satellite-based onset

    Science.gov (United States)

    Fisher, J. I.; Richardson, A. D.; Mustard, J. F.

    2006-12-01

    Seasonal temperature changes in temperate forests are known to trigger the start of spring growth, and both interannual and spatial variations in spring growth have been tied to climatic variability. Satellite data are finding increased use in regional and global phenological studies, but to date there have been few efforts to rigorously tie remotely sensed phenology to surface climate records. Where satellite records have been compared to broad-scale climate patterns, broadleaf deciduous forests have typically been characterized as a single functional type and differences between communities ignored. We used a simple two-parameter spring warming model to explore the relationship between interannual climate variability and satellite-based phenology in New England broadleaf temperate forests. We employed daily air temperature records between 2000 and 2005 from 171 NOAA meteorological stations to parameterize a simple spring warming model predicting the date of MODIS half-maximum greenness (spring onset). We find that the best model starts accumulating heating degree days (HDD) after March 20th and when average daily temperatures exceed 5°C. Critical heat sums to reach onset range from 150 to 300 degree-days, with increasing requirements southward and in coastal regions. In our findings, the spring warming model offers little improvement on the photoperiod null model (i.e. the average date of onset). However, differences between the relative goodness-of-fit of the spring warming model compared to the null (coined the 'climate sensitivity ratio', or CSR) displayed unexpected spatial coherency. The spatial variation in CSR appears to be related to differences in forest composition, with clear differences between northern (beech-maple-birch) and central (oak-hickory) hardwood forests. The two forest types may respond to climate differently, with disparate sensitivities to the minimum temperature initiating spring growth (3 and 6°C, respectively). We conclude that

  1. Photonic Vector Processing Techniques for Radiofrequency Signals

    OpenAIRE

    PIQUERAS RUIPÉREZ, MIGUEL ÁNGEL

    2016-01-01

    [EN] The processing of radiofrequency signals using photonics means is a discipline that appeared almost at the same time as the laser and the optical fibre. Photonics offers the capability of managing broadband radiofrequency (RF) signals thanks to its low transmission attenuation, a variety of linear and non-linear phenomena and, recently, the potential to implement integrated photonic subsystems. These features open the door for the implementation of multiple functionalities including opti...

  2. Global solar radiation: comparison of satellite-based climatology with station records

    Science.gov (United States)

    Skalak, Petr; Zahradnicek, Pavel; Stepanek, Petr; Farda, Ales

    2016-04-01

    We analyze surface incoming shortwave radiation (SIS) from the SARAH dataset prepared by the EUMETSAT Climate Monitoring Satellite Applications Facility from satellite observations of the visible channels of the MVIRI and SEVIRI instruments onboard the geostationary Meteosat satellites. The satellite SIS data are evaluated within the period 1984-2014 on various time scales: from individual months and years to long-term climate means. The validation is performed using the ground measurements of global solar radiation (GLBR) carried out on 11 meteorological stations of the Czech Hydrometeorological Institute in the Czech Republic with at least 30 years long data series. Our aim is to explore whether the SIS data could potentially serve as an alternative source of information on GLBR outside of a relatively sparse network of meteorological stations recording GLBR. Acknowledgement: Supported by the Ministry of Education, Youth and Sports of the Czech Republic within the National Sustainability Program I (NPU I), grant number LO1415.

  3. Space Station Habitability Recommendations Based on a Systematic Comparative Analysis of Analogous Conditions

    Science.gov (United States)

    Stuster, Jack W.

    1986-01-01

    Conditions analogous to the proposed NASA Space Station are systematically analyzed in order to extrapolate design guidelines and recommendations concerning habitability and crew productivity. Analogous environments studied included Skylab, Sealab, Tektite, submarines, Antarctic stations and oil drilling platforms, among others. These analogues were compared and rated for size and composition of group, social organization, preparedness for mission, duration of tour, types of tasks, physical and psychological isolation, personal motivation, perceived risk, and quality of habitat and life support conditions. One-hundred design recommendations concerning, sleep, clothing, exercise, medical support, personal hygiene, food preparation, group interaction, habitat aesthetics, outside communications, recreational opportunities, privacy and personal space, waste disposal, onboard training, simulation and task preparation, and behavioral and physiological requirements associated with a microgravity environment, are provided.

  4. Intrahepatic biliary injuries associated with radiofrequency ablation of hepatic malignancies

    Institute of Scientific and Technical Information of China (English)

    FU Ying; YANG Wei; WU Jin-yu; YAN Kun; WU Wei; XING Bao-cai; CHEN Min-hua

    2011-01-01

    Background Biliary injury after radiofrequency ablation can cause serious consequences including death. However, there are limited data regarding bile duct changes with or without complications associated with radiofrequency ablation of hepatic malignancies. This study aimed to assess the incidence, prognosis and risk factors of intrahepatic biliary injury associated with radiofrequency ablation.Methods Between June 2001 and January 2009, 638 patients with hepatic malignancies (405 with hepatocellular carcinoma, and 233 with liver metastasis) who had 955 treatment sessions were enrolled in this study. Imaging and laboratory data, the course of treatment, and patient outcomes were reviewed retrospectively. The risk factors of biliary injury and the impact on overall survival of patients were analyzed. The chi-square test, Fisher's exact test, Kaplan-Meier curves and stepwise Logistic regression model were used for statistical analysis where appropriate.Results Biliary injury was observed in 17 patients after 17 ablation sessions based on imaging findings. The overall incidence of biliary injury was 1.8% (17/955) with an average onset time of 12 weeks (2-36 weeks). Mild, moderate and severe complications of biliary injury were identified in 9, 6 and 2 cases, respectively. The median survival time after detection of biliary injury was 40 months. There seemed no notable difference in overall survival between patients with and those without biliary injuries. By multivariate analysis, vessel infiltration (P=0.034) and treatment session ≥4 times (P=0.025) were independent risk factors for biliary injury of hepatocellular carcinoma; while tumor located centrally was the only independent risk factor in the metastasis group (P=0.043).Conclusions The incidence of biliary injury was not frequent (1.8%). Through appropriate treatment, intrahepatic bile duct injuries seemed not affect the patients' long-term survival. Additionally, risk factors may be helpful for selecting

  5. Evaluation of areal precipitation estimates based on downscaled reanalysis and station data by hydrological modelling

    OpenAIRE

    Duethmann, D.; Zimmer, J.; A. Gafurov; Güntner, A.; B. Merz; Vorogushyn, S.

    2012-01-01

    In data sparse regions, as in many mountainous catchments, it is a challenge to generate suitable precipitation input fields for hydrological modelling, as station data do not provide enough information to derive areal precipitation estimates. This study presents a method using the spatial variation of precipitation from downscaled reanalysis data for the interpolation of gauge observations. The second aim of this study is the evaluation of different precipitation estimates by hydrolog...

  6. Accuracy analysis and Calibration of Total Station based on the Reflectorless Distance Measurement

    OpenAIRE

    Reda Adinew, Amezene; Bedada Damtie, Bekele

    2012-01-01

    Abstract Reflectorless EDM technology uses phase measuring or pulsed lasers to measure targets of a reflective and non-reflective nature. Reflectorless distance measurement provides rapid measurement by saving time and labour for surveyors. However, the accuracy of these types of measurements is under question because of the variety of constraints that affect the measurement. This paper attempts to show the techniques of total station calibration and to investigate the possible sources of err...

  7. Design of a silica-aerogel-based cosmic dust collector for the Tanpopo mission aboard the International Space Station

    CERN Document Server

    Tabata, Makoto; Yano, Hajime; Hashimoto, Hirofumi; Kawai, Hideyuki; Kawaguchi, Yuko; Kobayashi, Kensei; Mita, Hajime; Okudaira, Kyoko; Sasaki, Satoshi; Yabuta, Hikaru; Yokobori, Shin-ichi; Yamagishi, Akihiko

    2014-01-01

    We are developing a silica-aerogel-based cosmic dust collector for use in the Tanpopo experiment to be conducted on the International Space Station. The mass production of simple two-layer hydrophobic aerogels was undertaken in a contamination-controlled environment, yielding more than 100 undamaged products. The collector, comprising an aerogel tile and holder panel, was designed to resist launch vibration and to conform to an exposure attachment. To this end, a box-framing aerogel with inner and outer densities of 0.01 and 0.03 g/cm$^3$, respectively, was fabricated. The aerogel mounted in the panel passed random vibration tests at the levels of the acceptance and qualification tests for launch. It also withstood the pressure changes expected in the airlock on the International Space Station.

  8. Experimental station for laser-based picosecond time-resolved x-ray absorption near-edge spectroscopy

    International Nuclear Information System (INIS)

    We present an experimental station designed for time-resolved X-ray Absorption Near-Edge Spectroscopy (XANES). It is based on ultrashort laser-plasma x-ray pulses generated from a table-top 100 mJ-class laser at 10 Hz repetition rate. A high transmission (10%–20%) x-ray beam line transport using polycapillary optics allows us to set the sample in an independent vacuum chamber, providing high flexibility over a wide spectral range from 0.5 up to 4 keV. Some XANES spectra are presented, demonstrating 1% noise level in only ∼1 mn and ∼100 cumulated laser shots. Time-resolved measurements are reported, indicating that the time resolution of the entire experimental station is 3.3 ± 0.6 ps rms

  9. Fuel efficient operation of compressor stations using simulation-based optimization

    Energy Technology Data Exchange (ETDEWEB)

    Krishnaswami, P.; Chapman, K.S.; Abbaspour, M. [Kansas State Univ., Manhattan, KS (United States). National Gas Machinery Laboratory

    2004-07-01

    This paper presented a powerful solution process for optimizing the operation of a gas compressor station by minimizing fuel consumption while maintaining the desired throughput of natural gas in a pipeline. The first step in the solution process involved the creation of an analysis scheme that provided the simulation support needed by the optimization. This was accomplished by developing an implicit finite difference formulation of the continuity, momentum and energy equations for flow under non-isothermal conditions. The performance of each compressor unit was simulated by fitting polynomials to the compressor map. These were then appended to the flow equations to derive a complete set of system governing equations. A Newton-Raphson operation was used to obtain system performance of the resulting nonlinear algebraic equations. The design variables in the nonlinear programming (NLP) problem included compressor unit speed and the objective to minimize fuel consumption. In order to ensure that adequate flow was maintained while minimizing fuel consumption, a constraint was placed on the minimum flow rate through the compressor station. A sequential unconstrained minimization technique (SUMT) was used to solve the NLP. The simulation algorithm can be used whenever it is necessary to evaluate the system response at any given operating point. The simulation was shown to satisfactorily predict system response and was highly effective in minimizing fuel consumption. It was concluded that the approach can be utilized in single or sequence gas compressor stations along a pipeline. 23 refs., 5 tabs., 9 figs.

  10. Space station data system analysis/architecture study. Task 1: Functional requirements definition, DR-5. Appendix: Requirements data base

    Science.gov (United States)

    1985-01-01

    Appendix A contains data that characterize the system functions in sufficient depth as to determine the requirements for the Space Station Data System (SSDS). This data is in the form of: (1) top down traceability report; (2) bottom up traceability report; (3) requirements data sheets; and (4) cross index of requirements paragraphs of the source documents and the requirements numbers. A data base users guide is included that interested parties can use to access the requirements data base and get up to date information about the functions.

  11. Nonionising radiation and risk of human cancer: comparison of ultraviolet and radiofrequency radiation

    International Nuclear Information System (INIS)

    Human exposure to ultraviolet radiation (UVR) comes largely from sunlight, although a small proportion of people receive high dose UVR from artificial sources. The causal link between solar UVR and the keratinocyte cancers, basal cell carcinomas and squamous cell carcinomas of the skin, is well-established based on a large body of observational and experimental evidence. UVR damages molecules such as DNA directly and this is the principal mechanism of carcinogenesis, though other mechanisms such as immunosuppression and interaction with viruses may also be involved. People are also exposed to another form of nonionising radiation, radiofrequency radiation (RFR), through occupation, the community environment from base stations, and through use of cellular telephones and related communications devices. However, unlike UVR, the relationship between RFR and cancer is far from clear. The main tumours that have been investigated to date are brain tumours and leukaemia but assessing the RFR exposure pathway to such cancers poses many methodological challenges for epidemiologists. Refinements to measurement of exposure are the major urgent need, and the lack of evidence regarding carcinogenic effects of RFR in experimental settings complicates the assessment. Further insights into the links between RFR and chronic disease such as cancer are likely in the next few years however when results of several large-scale epidemiological studies now in train around the world become available

  12. Cutaneous remodeling and photorejuvenation using radiofrequency devices

    Directory of Open Access Journals (Sweden)

    Elsaie Mohamed

    2009-01-01

    Full Text Available Radio frequency (RF is electromagnetic radiation in the frequency range of 3-300GHz. The primary effects of RF energy on living tissue are considered to be thermal. The goal of the new devices based on these frequency ranges is to heat specific layers of the skin. The directed use of RF can induce dermal heating and cause collagen degeneration. Wound healing mechanisms promote the remodeling of collagen and wound contraction, which ultimately clinically enhances the appearance of mild to moderate skin laxity. Preliminary studies have reported efficacy in the treatment of laxity that involves the periorbital area and jowls. Because RF energy is not dependent on specific chromophore interaction, epidermal melanin is not at risk of destruction and treatment of all skin types is possible. As such, radiofrequency-based systems have been used successfully for nonablative skin rejuvenation, atrophic scar revision and treatment of unwanted hair, vascular lesions and inflammatory acne. The use of RF is becoming more popular, although a misunderstanding exists regarding the mechanisms and limitations of its actions. This concise review serves as an introduction and guide to many aspects of RF in the non ablative rejuvenation of skin.

  13. Characterization of tracked radiofrequency ablation in phantom

    International Nuclear Information System (INIS)

    In radiofrequency ablation (RFA), successful therapy requires accurate, image-guided placement of the ablation device in a location selected by a predictive treatment plan. Current planning methods rely on geometric models of ablations that are not sensitive to underlying physical processes in RFA. Implementing plans based on computational models of RFA with image-guided techniques, however, has not been well characterized. To study the use of computational models of RFA in planning needle placement, this work compared ablations performed with an optically tracked RFA device with corresponding models of the ablations. The calibration of the tracked device allowed the positions of distal features of the device, particularly the tips of the needle electrodes, to be determined to within 1.4±0.6 mm of uncertainty. Ablations were then performed using the tracked device in a phantom system based on an agarose-albumin mixture. Images of the sliced phantom obtained from the ablation experiments were then compared with the predictions of a bioheat transfer model of RFA, which used the positional data of the tracked device obtained during ablation. The model was demonstrated to predict 90% of imaged pixels classified as being ablated. The discrepancies between model predictions and observations were analyzed and attributed to needle tracking inaccuracy as well as to uncertainties in model parameters. The results suggest the feasibility of using finite element modeling to plan ablations with predictable outcomes when implemented using tracked RFA

  14. The safety and efficacy of a combined diode laser and bipolar radiofrequency compared with combined infrared light and bipolar radiofrequency for skin rejuvenation

    Directory of Open Access Journals (Sweden)

    Yeon Jin Choi

    2012-01-01

    Full Text Available Background: As the demand for noninvasive procedures for skin rejuvenation is increasing, combined diode laser and radiofrequency and combined infrared and radiofrequency devices have recently emerged. Aim: To compare Polaris WRA TM , a combination device of diode light and RF, and ReFirme ST TM , a combination device of infrared and bipolar RF, in terms of safety and efficacy on skin rejuvenation. Methods: Fourteen Korean volunteers of skin type II-IV, with facial laxity and periorbital rhytids, received three treatments at 3-week intervals with combined diode laser and bipolar radiofrequency (laser fluence 30 J/cm 2 , RF fluence 90 J/cm 3 on the right half of their faces and combined infrared light and bipolar radiofrequency (RF fluence 120 J/cm 3 on the left half of their faces. Clinical photos of front and bilateral sides of the subjects′ faces were taken at baseline and at 6, 9, 12 weeks after the treatment initiation. The investigators′ and the subjects′ global assessments were performed. Results: There is no statistically significant difference in the overall outcome between Polaris WRA TM and Refirme ST TM based on pre- and post-treatment objective measurements. Polaris WRA TM was more effective than Refirme ST TM at reducing wrinkles when therapeutic results of the two appliances were compared based on the patient satisfaction measurements. After the treatment with both instruments, histological increase in the production and rearrangement of collagen fibers at the dermal layer was observed. The density of the collagen fibers was more increased with the Polaris WRA TM -treated facial area than that of Refirme ST TM . Treatment was generally well tolerated, and there was no serious complication. Conclusion: In this study, both the lasers appeared to be safe, and effective methods for treating skin laxity and facial wrinkles. Combined diode laser and radiofrequency was more effective than combined infrared and radiofrequency at

  15. Clinically defined non-specific symptoms in the vicinity of mobile phone base stations: A retrospective before-after study.

    Science.gov (United States)

    Baliatsas, Christos; van Kamp, Irene; Bolte, John; Kelfkens, Gert; van Dijk, Christel; Spreeuwenberg, Peter; Hooiveld, Mariette; Lebret, Erik; Yzermans, Joris

    2016-09-15

    The number of mobile phone base station(s) (MPBS) has been increasing to meet the rapid technological changes and growing needs for mobile communication. The primary objective of the present study was to test possible changes in prevalence and number of NSS in relation to MPBS exposure before and after increase of installed MPBS antennas. A retrospective cohort study was conducted, comparing two time periods with high contrast in terms of number of installed MPBS. Symptom data were based on electronic health records from 1069 adult participants, registered in 9 general practices in different regions in the Netherlands. All participants were living within 500m from the nearest bases station. Among them, 55 participants reported to be sensitive to MPBS at T1. A propagation model combined with a questionnaire was used to assess indoor exposure to RF-EMF from MPBS at T1. Estimation of exposure at T0 was based on number of antennas at T0 relative to T1. At T1, there was a >30% increase in the total number of MPBS antennas. A higher prevalence for most NSS was observed in the MPBS-sensitive group at T1 compared to baseline. Exposure estimates were not associated with GP-registered NSS in the total sample. Some significant interactions were observed between MPBS-sensitivity and exposure estimates on risk of symptoms. Using clinically defined outcomes and a time difference of >6years it was demonstrated that RF-EMF exposure to MPBS was not associated with the development of NSS. Nonetheless, there was some indication for a higher risk of NSS for the MPBS-sensitive group, mainly in relation to exposure to UMTS, but this should be interpreted with caution. Results have to be verified by future longitudinal studies with a particular focus on potentially susceptible population subgroups of large sample size and integrated exposure assessment. PMID:27219506

  16. Vapor Online Monitor Model of Vapor Power Station Based on UML

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    We presents a vapor online monitor system model of vapor power station developed by visual tool rational rose2000. Use cases such as on line instrument (onlineinstr), control, query, report, real database (realdb) and alarm are generated according to the system requirements. Use case view and class view of the system are formed at the same time. As for all the UML models of the system, this paper focuses the discussion on the class view, the component diagram of the control class and the sequence diagram of the query class. Corresponding C++ codes are produced and finally transferred into the spot running software.

  17. EMTP based stability analysis of space station electric power system in a test bed environment

    Science.gov (United States)

    Dravid, Narayan V.; Kacpura, Thomas J.; Oconnor, Andrew M.

    1992-01-01

    The Space Station Freedom Electric Power System (EPS) will convert solar energy into electric energy and distribute the same using an 'all dc', Power Management and Distribution (PMAD) System. Power conditioning devices (dc to dc converters) are needed to interconnect parts of this system operating at different nominal voltage levels. Operation of such devices could generate under damped oscillations (instability) under certain conditions. Criteria for instability are examined and verified for a single device. Suggested extension of the criteria to a system operation is examined by using the EMTP model of the PMAD DC test bed. Wherever possible, data from the test bed is compared with the modeling results.

  18. Dielectric-filled radiofrequency linacs

    International Nuclear Information System (INIS)

    High current, high brightness electron beam accelerators promise to open up dramatic new applications. Linear induction accelerators are currently viewed as the appropriate technology for these applications. A concept by Humphries and Hwang may permit radiofrequency accelerators to fulfill the same functions with greater simplicity and enhanced flexibility. This concept involves the replacement of vacuum rf cavities with dielectric filled ones. Simple analysis indicates that the resonant frequencies are reduced by a factor of (ε0/ε)1/2 while the stored energy is increased by ε/ε0. For a high dielectric constant like water, this factor can approach 80. A series of numerical calculations of simple pill-box cavities was performed. Eigenfunctions and resonant frequencies for a full system configuration, including dielectric material, vacuum beamline, and a ceramic window separating the two have been computed. These calculations are compared with the results of a small experimental cavity which have been constructed and operated. Low power tests show excellent agreement. (author). 4 figs., 8 refs

  19. Radiofrequency ablation of liver metastases

    International Nuclear Information System (INIS)

    The liver is the second only to lymph nodes as the most common site of metastatic disease irrespective of the primary tumor. Up to 50% of all patients with malignant diseases will develop liver metastases with a significant morbidity and mortality. Although the surgical resection leads to an improvement of the survival time, only approximately 20% of the patients are eligible for surgical intervention. Radiofrequency (RF) ablation represents one of the most important alternatives as well as complementary methods for the therapy of liver metastases. RF ablation can lead in a selected patient group to a palliation or to an increased life expectancy. RF ablation appears either safer (vs. cryotherapy) or easier (vs. laser) or more effective (percutaneous ethanol instillation [PEI]), transarterial chemoembolisation [TACE] in comparison with other minimal invasive procedures. RF ablation can be performed percutaneously, laparoscopically or intraoperatively and may be combined with chemotherapy as well as with surgical resection. Permanent technical improvements of RF systems, a better understanding of the underlying electrophysiological principles and an interdisciplinary approach will lead to a prognosis improvement in patients with liver metastases. (orig.)

  20. Optimization of energy saving decisions for the large compressor stations of machine-building firms based on the technical and economic indicators

    Science.gov (United States)

    Khamidullina, G. R.

    2016-06-01

    We offer the method of energy-efficiency measures improvement based on optimization of its technical and economic indicators. As an object of research is considered the high-capacity compressor station of the machine-building enterprise.

  1. STUDY ON POWER SPARE COEFFICIENT OF ELECTRICAL MOTOR IN LARGE PUMP STATION BASED ON RELIABILITY

    Institute of Scientific and Technical Information of China (English)

    Qiu Baoyun; Huang Jiyan; Yuan Shouqi

    2004-01-01

    Characters of head of low head pump station and the pump shaft power are analyzed. Influence of each single factor on pump shaft power is expressed as change of specific shaft power (non-dimensional) and the probability density function is determined. Influences of multiple factors on pump shaft power are analyzed. Method of calculating none over-loaded probability of motor by integration by successive reductions is put forward and then relation between power spare coefficient and none over-loaded reliability of electric motor is established. Influences of all factors on pump shaft power being considered completely; power spare coefficients of motor are calculated in three kinds of heads (changing and unchanging), two kinds of dirty-out conditions. Electrical motor power spare coefficients should be chosen as 1.20~1.44, 1.11~1.19, 1.09~1.14 respectively when pump heads are 4, 7, 9.5 m. The results mean much to reasonable choose of electrical motors in large pump stations, increasing reliability of pump units and saving equipment investment.

  2. Metamaterial radiofrequency lens for magnetic resonance imaging

    CERN Document Server

    Freire, Manuel J; Jelinek, Lukas; Gil, Eduardo; Moya, Francisco

    2009-01-01

    The purpose of this work is to test the ability of a new class of passive electromagnetic device to increase the penetration depth of phased arrays of surface coils for magnetic resonance (MR) imaging systems. This new device is based on the emerging technology of metamaterials and behaves like a lens for the radiofrequency magnetic fields. The presented device was tested in several 1.5-T MR systems from different companies in combination with different phased arrays. One of the authors was enrolled as volunteer for the experiments. In these experiments his knees were imaged by using a dual phased array. The device was placed between the knees to check that the penetration depth of the coils was improved by this passive device. In all the experiments the presented device was successfully tested and it was checked that the knees of the volunteer can be imaged at deeper distances and that the signal-to-noise-ratio (SNR) in the obtained MR images was improved by the presence of the lens. The presented device has...

  3. Evaluation of radiofrequency dielectric heaters workers exposure

    International Nuclear Information System (INIS)

    Radiofrequency dielectric heaters (RFDH) are widely used in the woodworking industry for gluing laminates by applying pressure and RF heating. The workers operating such equipment remain in the vicinity of the machinery all day and can therefore be exposed to considerable levels of electric and magnetic field at RFs. This work describes the method used to measure the strength of fields generated by this particular machinery. This procedure is based on current methods cited in the literature and introduces the necessary modifications to meet this specific case. In particular, as there is often a scarcity of technical data available relating to such heaters, it is suggested that a spectrum analyser be used for measurements in the frequencies domain. On the basis of the data obtained the norms of reference are established, the instrumentation to be used in successive stages determined as well as the identification of possible sources of interference from spurious signals. Furthermore, a mapping of the field strengths is presented and the means of determining the decay curve as a function of distance. This last type of measurement is done to estimate the effectiveness of grounding the machinery. The report ends with an estimate of the exposure of workers to electromagnetic fields and also some recommendations for reducing risk. (authors)

  4. Radiofrequency radiation leakage from microwave ovens

    International Nuclear Information System (INIS)

    This work presents data on the amount of radiation leakage from 117 microwave ovens in domestic and restaurant use in the West Bank, Palestine. The study of leakage is based on the measurements of radiation emissions from the oven in real-life conditions by using a frequency selective field strength measuring system. The power density from individual ovens was measured at a distance of 1 m and at the height of centre of door screen. The tested ovens were of different types, models with operating powers between 1000 and 1600 W and ages ranging from 1 month to >20 y, including 16 ovens with unknown ages. The amount of radiation leakage at a distance of 1 m was found to vary from 0.43 to 16.4 μW cm-1 with an average value equalling 3.64 μW cm-2. Leakages from all tested microwave ovens except for seven ovens (∼6 % of the total) were below 10 μW cm-2. The highest radiation leakage from any tested oven was ∼16.4 μW cm-2, and found in two cases only. In no case did the leakage exceed the limit of 1 μWcm-1 recommended by the ICNIRP for 2.45-GHz radiofrequency. This study confirms a linear correlation between the amount of leakage and both oven age and operating power, with a stronger dependence of leakage on age. (authors)

  5. Optimization of measurement methods for a multi-frequency electromagnetic field from mobile phone base station using broadband EMF meter

    Directory of Open Access Journals (Sweden)

    Paweł Bieńkowski

    2015-10-01

    Full Text Available Background: This paper presents the characteristics of the mobile phone base station (BS as an electromagnetic field (EMF source. The most common system configurations with their construction are described. The parameters of radiated EMF in the context of the access to methods and other parameters of the radio transmission are discussed. Attention was also paid to antennas that are used in this technology. Material and Methods: The influence of individual components of a multi-frequency EMF, most commonly found in the BS surroundings, on the resultant EMF strength value indicated by popular broadband EMF meters was analyzed. The examples of metrological characteristics of the most common EMF probes and 2 measurement scenarios of the multisystem base station, with and without microwave relays, are shown. Results: The presented method for measuring the multi-frequency EMF using 2 broadband probes allows for the significant minimization of measurement uncertainty. Equations and formulas that can be used to calculate the actual EMF intensity from multi-frequency sources are shown. They have been verified in the laboratory conditions on a specific standard setup as well as in real conditions in a survey of the existing base station with microwave relays. Conclusions: Presented measurement methodology of multi-frequency EMF from BS with microwave relays, validated both in laboratory and real conditions. It has been proven that the described measurement methodology is the optimal approach to the evaluation of EMF exposure in BS surrounding. Alternative approaches with much greater uncertainty (precaution method or more complex measuring procedure (sources exclusion method are also presented. Med Pr 2015;66(5:701–712

  6. New resonant circuits for the ISOLTRAP radiofrequency quadrupole trap

    CERN Document Server

    SENECAL, Pierre

    2015-01-01

    This report describes my work during my Summer Student Program. My main project was building and testing a resonance-circuit box for a radio-frequency power supply used with the radio-frequency cooler and buncher.

  7. Eddy current imaging with an atomic radio-frequency magnetometer

    CERN Document Server

    Wickenbrock, Arne; Blanchard, John W; Budker, Dmitry

    2016-01-01

    We use a radio-frequency $^{85}$Rb alkali-vapor cell magnetometer based on a paraffin-coated cell with long spin-coherence time and a small, low-inductance driving coil to create highly resolved conductivity maps of different objects. We resolve sub-mm features in conductive objects, we characterize the frequency response of our technique, and by operating at frequencies up to 250 kHz we are able to discriminate between differently conductive materials based on the induced response. The method is suited to cover a wide range of driving frequencies and can potentially be used for detecting non-metallic objects with low DC conductivity.

  8. Eddy current imaging with an atomic radio-frequency magnetometer

    Science.gov (United States)

    Wickenbrock, Arne; Leefer, Nathan; Blanchard, John W.; Budker, Dmitry

    2016-05-01

    We use a radio-frequency 85Rb alkali-vapor cell magnetometer based on a paraffin-coated cell with long spin-coherence time and a small, low-inductance driving coil to create highly resolved conductivity maps of different objects. We resolve sub-mm features in conductive objects, we characterize the frequency response of our technique, and by operating at frequencies up to 250 kHz we are able to discriminate between differently conductive materials based on the induced response. The method is suited to cover a wide range of driving frequencies and can potentially be used for detecting non-metallic objects with low DC conductivity.

  9. Assessment of the temporal trend of the exposure of people to electromagnetic fields produced by base stations for mobile telephones

    International Nuclear Information System (INIS)

    Monitoring of electric field levels produced by base stations (BSs) for mobile telephones of different typologies (TACS, GSM, DCS) has been carried out. Results show that BSs can be classified as 'business' or 'residential'. The mean value of six minutes average E-field value measured between 10 am and 1 pm corresponds to the 84% of the maximum daily six minutes averaged value. Comparison between electromagnetic field levels produced by BSs and their phone traffic data, supplied by companies, is shown. Finally, on an hourly average basis, a daily curve has been constructed of the exposure trend produced by such installations. (author)

  10. Emergency Medical Service (EMS) Stations

    Data.gov (United States)

    Kansas Data Access and Support Center — EMS Locations in Kansas The EMS stations dataset consists of any location where emergency medical services (EMS) personnel are stationed or based out of, or where...

  11. Amtrak Stations

    Data.gov (United States)

    Department of Homeland Security — Updated database of the Federal Railroad Administration's (FRA) Amtrak Station database. This database is a geographic data set containing Amtrak intercity railroad...

  12. DS-CDMA Cellular Systems Performance with Base Station Assignment, Power Control Error and Beamforming over Multipath Fading

    Directory of Open Access Journals (Sweden)

    Mohamad Dosaranian Moghadam

    2011-01-01

    Full Text Available The interference reduction capability of antenna arrays, base station assignment and the power controlalgorithms have been considered separately as means to increase the capacity in wireless communicationnetworks. In this paper, we propose base station assignment method based on minimizing the transmitterpower (BSA-MTP technique in a direct sequence-code division multiple access (DS-CDMA receiver inthe presence of frequency-selective Rayleigh fading and power control error (PCE. This receiverconsists of constrained least mean squared (CLMS algorithm, matched filter (MF, and maximal ratiocombining (MRC in three stages. Also, we present switched-beam (SB technique in the first stage of theRAKE receiver for enhancing signal to interference plus noise ratio (SINR in DS-CDMA cellularsystems. The simulation results indicate that BSA-MTP technique can significantly improve the networkbit error rate (BER in comparison with the conventional case. Finally, we discuss on three parameters ofthe PCE, number of resolvable paths, and channel propagation conditions (path-loss exponent andshadowing and their effects on capacity of the system via some computer simulations.

  13. Primary Dendrite Array Morphology: Observations from Ground-based and Space Station Processed Samples

    Science.gov (United States)

    Tewari, Surendra; Rajamure, Ravi; Grugel, Richard; Erdmann, Robert; Poirier, David

    2012-01-01

    Influence of natural convection on primary dendrite array morphology during directional solidification is being investigated under a collaborative European Space Agency-NASA joint research program, "Microstructure Formation in Castings of Technical Alloys under Diffusive and Magnetically Controlled Convective Conditions (MICAST)". Two Aluminum-7 wt pct Silicon alloy samples, MICAST6 and MICAST7, were directionally solidified in microgravity on the International Space Station. Terrestrially grown dendritic monocrystal cylindrical samples were remelted and directionally solidified at 18 K/cm (MICAST6) and 28 K/cm (MICAST7). Directional solidification involved a growth speed step increase (MICAST6-from 5 to 50 micron/s) and a speed decrease (MICAST7-from 20 to 10 micron/s). Distribution and morphology of primary dendrites is currently being characterized in these samples, and also in samples solidified on earth under nominally similar thermal gradients and growth speeds. Primary dendrite spacing and trunk diameter measurements from this investigation will be presented.

  14. An extensive survey of dayside diffuse aurora based on optical observations at Yellow River Station

    CERN Document Server

    Han, De-Sheng; Liu, Jian-Jun; Qiu, Qi; Keika, K; Hu, Ze-Jun; Liu, Jun-Ming; Hu, Hong-Qiao; Yang, Hui-Gen

    2016-01-01

    By using 7 years optical auroral observations obtained at Yellow River Station (magnetic latitude $76.24\\,^{\\circ}{\\rm C}$N) at Ny-Alesund, Svalbard, we performed the first extensive survey for the dayside diffuse auroras (DDAs) and acquired observational results as follows. (1) The DDAs can be classified into two broad categories, i.e., unstructured and structured DDAs. The unstructured DDAs are mainly distributed in the morning and afternoon, but the structured DDAs predominantly occurred around the magnetic local noon (MLN). (2) The unstructured DDAs observed in morning and afternoon present obviously different properties. The afternoon ones are much stable and seldom show pulsating property. (3) The DDAs are more easily observed under geomagnetically quiet times. (4) The structured DDAsmainly show patchy, stripy, and irregular forms and are often pulsating and drifting. The drifting directions are mostly westward (with speed $\\sim$5km/s), but there are cases showing eastward or poleward drifting. (5) The ...

  15. Evaluation of areal precipitation estimates based on downscaled reanalysis and station data by hydrological modelling

    Directory of Open Access Journals (Sweden)

    D. Duethmann

    2012-09-01

    Full Text Available In data sparse regions, as in many mountainous catchments, it is a challenge to generate suitable precipitation input fields for hydrological modelling, as station data do not provide enough information to derive areal precipitation estimates. This study presents a method using the spatial variation of precipitation from downscaled reanalysis data for the interpolation of gauge observations. The second aim of this study is the evaluation of different precipitation estimates by hydrological modelling. Study area is the Karadarya catchment in Central Asia (11 700 km2. ERA-40 reanalysis data are downscaled with the regional climate model Weather Research and Forecasting Model (WRF. Precipitation data from gauge observations are interpolated (i using monthly accumulated WRF precipitation data, (ii using monthly fields from multiple linear regression against topographical variables and (iii with the inverse distance approach. These precipitation data sets are also compared to (iv the direct use of the precipitation output from the WRF downscaled ERA-40 data and (v precipitation from the APHRODITE data set. Our study suggests that using monthly fields from downscaled reanalysis data can be a good approach for the interpolation of station data in data sparse mountainous regions. Compared to mean annual precipitation from continental and global scale gridded data sets our precipitation estimates for the study area are considerably higher. The introduction of a calibrated precipitation bias factor for the comparison of different precipitation estimates by hydrological modelling allows for a more informed differentiation with regard to the temporal dynamics, on the one hand, and the overall bias, on the other hand. Uncertainty and sensitivity analyses suggest that our results are robust against uncertainties in the calibration parameters, other model parameters and inputs, and the selected calibration period.

  16. A new source discriminant based on frequency dispersion for hydroacoustic phases recorded by T-phase stations

    Science.gov (United States)

    Talandier, Jacques; Okal, Emile A.

    2016-07-01

    In the context of the verification of the Comprehensive Nuclear-Test Ban Treaty in the marine environment, we present a new discriminant based on the empirical observation that hydroacoustic phases recorded at T-phase stations from explosive sources in the water column feature a systematic inverse dispersion, with lower frequencies traveling slower, which is absent from signals emanating from earthquake sources. This difference is present even in the case of the so-called "hotspot earthquakes" occurring inside volcanic edifices featuring steep slopes leading to efficient seismic-acoustic conversions, which can lead to misidentification of such events as explosions when using more classical duration-amplitude discriminants. We propose an algorithm for the compensation of the effect of dispersion over the hydroacoustic path based on a correction to the spectral phase of the ground velocity recorded by the T-phase station, computed individually from the dispersion observed on each record. We show that the application of a standard amplitude-duration algorithm to the resulting compensated time series satisfactorily identifies records from hotspot earthquakes as generated by dislocation sources, and present a full algorithm, lending itself to automation, for the discrimination of explosive and earthquake sources of hydroacoustic signals at T-phase stations. The only sources not readily identifiable consist of a handful of complex explosions which occurred in the 1970s, believed to involve the testing of advanced weaponry, and which should be independently identifiable through routine vetting by analysts. While we presently cannot provide a theoretical justification to the observation that only explosive sources generate dispersed T phases, we hint that this probably reflects a simpler, and more coherent distribution of acoustic energy among the various modes constituting the wavetrain, than in the case of dislocation sources embedded in the solid Earth.

  17. A new source discriminant based on frequency dispersion for hydroacoustic phases recorded by T-phase stations

    Science.gov (United States)

    Talandier, Jacques; Okal, Emile A.

    2016-09-01

    In the context of the verification of the Comprehensive Nuclear-Test Ban Treaty in the marine environment, we present a new discriminant based on the empirical observation that hydroacoustic phases recorded at T-phase stations from explosive sources in the water column feature a systematic inverse dispersion, with lower frequencies traveling slower, which is absent from signals emanating from earthquake sources. This difference is present even in the case of the so-called `hotspot earthquakes' occurring inside volcanic edifices featuring steep slopes leading to efficient seismic-acoustic conversions, which can lead to misidentification of such events as explosions when using more classical duration-amplitude discriminants. We propose an algorithm for the compensation of the effect of dispersion over the hydroacoustic path based on a correction to the spectral phase of the ground velocity recorded by the T-phase station, computed individually from the dispersion observed on each record. We show that the application of a standard amplitude-duration algorithm to the resulting compensated time-series satisfactorily identifies records from hotspot earthquakes as generated by dislocation sources, and present a full algorithm, lending itself to automation, for the discrimination of explosive and earthquake sources of hydroacoustic signals at T-phase stations. The only sources not readily identifiable consist of a handful of complex explosions which occurred in the 1970s, believed to involve the testing of advanced weaponry, and which should be independently identifiable through routine vetting by analysts. While we presently cannot provide a theoretical justification to the observation that only explosive sources generate dispersed T phases, we hint that this probably reflects a simpler, and more coherent distribution of acoustic energy among the various modes constituting the wave train, than in the case of dislocation sources embedded in the solid Earth.

  18. 47 CFR 2.801 - Radiofrequency device defined.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Radiofrequency device defined. 2.801 Section 2.801 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS AND RADIO TREATY MATTERS; GENERAL RULES AND REGULATIONS Marketing of Radio-frequency Devices § 2.801 Radiofrequency...

  19. 低辐射3G 网络基站选址优化∗%Optimized Planning of Low Electromagnetic Radiation 3G Network Base Station Location

    Institute of Scientific and Technical Information of China (English)

    张英杰; 孙先佑; 毛赐平; 王镇道; 许伟; 汤龙波; 艾朝阳

    2015-01-01

    针对民众因担忧电磁辐射而投诉日益增多导致通信基站选址困难的现状,在考虑基站覆盖范围和建站成本的同时,兼顾基站电磁辐射对环境的影响,提出了面向低辐射的3G网络基站选址优化方案。通过对基站选址原则及其典型基站的电磁辐射模型分析,建立了基于多目标的基站评价模型,设计了基于改进的免疫优化算法3G 网络基站选址优化方案,并以模拟实验区域为对象进行了仿真实验测试。实验结果表明:本文提出的选址优化方案不仅能以较小的基站建设代价满足信号覆盖要求,同时也降低了基站电磁辐射的影响,获得了更好的社会效益。%Increasingly more people are worried about the electromagnetic radiation of the communica-tion network base station.The growing number of complaints has made base station siting difficult.This paper considered base station coverage and costs,while taking into account the impact of electromagnetic radiation on the environment of the base station.An optimized low electromagnetic radiation 3G network base stations site selection scheme was proposed in this paper.With the base station siting principles and an analysis of the electromagnetic radiation of typical base stations,this paper established a base station evaluation model based on multi-objective design optimization algorithm and proposed a 3G network base station site selection method based on improved immune optimization.A simulation area was set up for simulation tests.The results show that the proposed base station optimization program can not only meet the coverage requirements with relatively smaller construction cost,but also reduce the impact of electro-magnetic radiation for better social benefits.

  20. Determining the validity of exposure models for environmental epidemiology : predicting electromagnetic fields from mobile phone base stations

    OpenAIRE

    Beekhuizen, Johan

    2014-01-01

    One of the key challenges in environmental epidemiology is the exposure assessment of large populations. Spatial exposure models have been developed that predict exposure to the pollutant of interest for large study sizes. However, the validity of these exposure models is often unknown. In this thesis, we present various aspects that are important for quantifying the accuracy and uncertainty of model predictions. We focus on modelling radiofrequency electromagnetic fields (RF-EMF) from mobile...

  1. Feasibility of a cohort study on health risks caused by occupational exposure to radiofrequency electromagnetic fields

    Directory of Open Access Journals (Sweden)

    Wahrendorf Jürgen

    2009-05-01

    Full Text Available Abstract Background The aim of this study was to examine the feasibility of performing a cohort study on health risks from occupational exposure to radiofrequency electromagnetic fields (RF-EMF in Germany. Methods A set of criteria was developed to evaluate the feasibility of such a cohort study. The criteria aimed at conditions of exposure and exposure assessment (level, duration, preferably on an individual basis, the possibility to assemble a cohort and the feasibility of ascertaining various disease endpoints. Results Twenty occupational settings with workers potentially exposed to RF-EMF and, in addition, a cohort of amateur radio operators were considered. Based on expert ratings, literature reviews and our set of predefined criteria, three of the cohorts were identified as promising for further evaluation: the personnel (technicians of medium/short wave broadcasting stations, amateur radio operators, and workers on dielectric heat sealers. After further analyses, the cohort of workers on dielectric heat sealers seems not to be feasible due to the small number of exposed workers available and to the difficulty of assessing exposure (exposure depends heavily on the respective working process and mixture of exposures, e.g. plastic vapours, although exposure was highest in this occupational setting. The advantage of the cohort of amateur radio operators was the large number of persons it includes, while the advantage of the cohort of personnel working at broadcasting stations was the quality of retrospective exposure assessment. However, in the cohort of amateur radio operators the exposure assessment was limited, and the cohort of technicians was hampered by the small number of persons working in this profession. Conclusion The majority of occupational groups exposed to RF-EMF are not practicable for setting up an occupational cohort study due to the small numbers of exposed subjects or due to exposure levels being only marginally higher

  2. Radiofrequency electromagnetic radiation exposure inside the metro tube infrastructure in Warszawa.

    Science.gov (United States)

    Gryz, Krzysztof; Karpowicz, Jolanta

    2015-09-01

    Antennas from various wireless communications systems [e.g. mobile phones base transceiver stations (BTS) and handsets used by passengers, public Internet access, staff radiophone transmitters used between engine-drivers and traffic operators] emitting radiofrequency electromagnetic radiation (RF-EMR) are used inside underground metro public transportation. Frequency-selective exposimetric investigations of RF-EMR exposure inside the metro infrastructure in Warsaw (inside metro cars passing between stations and on platforms) were performed. The statistical parameters of exposure to the E-field were analyzed for each frequency range and for a total value (representing the wide-band result of measurements of complex exposure). The recorded exposimetric profiles showed the dominant RF-EMR sources: handsets and BTS of mobile communication systems (GSM 900 and UMTS 2100) and local wireless Internet access (WiFi 2G). Investigations showed that the GSM 900 system is the dominant source of exposure - BTS (incessantly active) on platforms, and handsets - used by passengers present nearby during the tube drive. The recorded E-field varies between sources (for BTS were: medians - 0.22 V/m and 75th percentile - 0.37 V/m; and for handsets: medians - 0.28 V/m and 75th percentile - 0.47 V/m). Maximum levels (peaks) of exposure recorded from mobile handsets exceeded 10 V/m (upper limit of used exposimeters). Broadband measurements of E-field, including the dominant signal emitted by staff radiophones (151 MHz), showed that the level of this exposure of engine-drivers does not exceed 2.5 V/m. PMID:26444204

  3. Evaluation Of Geo-Spatial Proximity Of Mobile Communication GSM Base Transceiver Stations To Buildings In Ile-Ife Nigeria

    Directory of Open Access Journals (Sweden)

    Badru

    2015-08-01

    Full Text Available Efficient placement of radio facilities for the communication base transceiver station CBS of the two small global system for mobile communication GSM has being an area of research due to fast growing of GSM market in Nigeria. In line with this development Nigerian Communication Commission NCC and Nigeria Environmental Standard and Regulation Enforcement Agency NESREA have stated the setback between communication base station and the nearest infrastructure as 5 m and 10 m respectively. To evaluate the degree of the implementation of these setbacks in Ile-Ife the study area the research study identified the spatial locations of the CBS using a global communication for satellite GPS receiver and also employed the use of a high resolution satellite imagery which were processed using geo-spatial techniques. The results of this study revealed that 45.6 and 59.5 of the CBS had setback to building structures at 5 m and 10 m respectively with spatial variability between 30 m to 17074 m at elevation between 193 m to 377 m.

  4. Research on ISFLA-Based Optimal Control Strategy for the Coordinated Charging of EV Battery Swap Station

    Directory of Open Access Journals (Sweden)

    Xueliang Huang

    2013-01-01

    Full Text Available As an important component of the smart grid, electric vehicles (EVs could be a good measure against energy shortages and environmental pollution. A main way of energy supply to EVs is to swap battery from the swap station. Based on the characteristics of EV battery swap station, the coordinated charging optimal control strategy is investigated to smooth the load fluctuation. Shuffled frog leaping algorithm (SFLA is an optimization method inspired by the memetic evolution of a group of frogs when seeking food. An improved shuffled frog leaping algorithm (ISFLA with the reflecting method to deal with the boundary constraint is proposed to obtain the solution of the optimal control strategy for coordinated charging. Based on the daily load of a certain area, the numerical simulations including the comparison of PSO and ISFLA are carried out and the results show that the presented ISFLA can effectively lower the peak-valley difference and smooth the load profile with the faster convergence rate and higher convergence precision.

  5. Transmit Power Minimization and Base Station Planning for High-Speed Trains with Multiple Moving Relays in OFDMA Systems

    KAUST Repository

    Ghazzai, Hakim

    2016-03-15

    High-speed railway system equipped with moving relay stations placed on the middle of the ceiling of each train wagon is investigated. The users inside the train are served in two hops via the orthogonal frequency-division multiple access (OFDMA) technology. In this work, we first focus on minimizing the total downlink power consumption of the base station (BS) and the moving relays while respecting specific quality of service (QoS) constraints. We first derive the optimal resource allocation solution in terms of OFDMA subcarriers and power allocation using the dual decomposition method. Then, we propose an efficient algorithm based on the Hungarian method in order to find a suboptimal but low complexity solution. Moreover, we propose an OFDMA planning solution for high-speed train by finding the maximal inter-BS distance given the required user data rates in order to perform seamless handover. Our simulation results illustrate the performance of the proposed resource allocation schemes in the case of the 3GPP Long Term Evolution-Advanced (LTE-A) and compare them with previously developed algorithms as well as with the direct transmission scenario. Our results also highlight the significant planning gain obtained thanks to the use of multiple relays instead of the conventional single relay scenario.

  6. National Scale Rainfall Map Based on Linearly Interpolated Data from Automated Weather Stations and Rain Gauges

    Science.gov (United States)

    Alconis, Jenalyn; Eco, Rodrigo; Mahar Francisco Lagmay, Alfredo; Lester Saddi, Ivan; Mongaya, Candeze; Figueroa, Kathleen Gay

    2014-05-01

    In response to the slew of disasters that devastates the Philippines on a regular basis, the national government put in place a program to address this problem. The Nationwide Operational Assessment of Hazards, or Project NOAH, consolidates the diverse scientific research being done and pushes the knowledge gained to the forefront of disaster risk reduction and management. Current activities of the project include installing rain gauges and water level sensors, conducting LIDAR surveys of critical river basins, geo-hazard mapping, and running information education campaigns. Approximately 700 automated weather stations and rain gauges installed in strategic locations in the Philippines hold the groundwork for the rainfall visualization system in the Project NOAH web portal at http://noah.dost.gov.ph. The system uses near real-time data from these stations installed in critical river basins. The sensors record the amount of rainfall in a particular area as point data updated every 10 to 15 minutes. The sensor sends the data to a central server either via GSM network or satellite data transfer for redundancy. The web portal displays the sensors as a placemarks layer on a map. When a placemark is clicked, it displays a graph of the rainfall data for the past 24 hours. The rainfall data is harvested by batch determined by a one-hour time frame. The program uses linear interpolation as the methodology implemented to visually represent a near real-time rainfall map. The algorithm allows very fast processing which is essential in near real-time systems. As more sensors are installed, precision is improved. This visualized dataset enables users to quickly discern where heavy rainfall is concentrated. It has proven invaluable on numerous occasions, such as last August 2013 when intense to torrential rains brought about by the enhanced Southwest Monsoon caused massive flooding in Metro Manila. Coupled with observations from Doppler imagery and water level sensors along the

  7. Electromagnetic induction imaging with a radio-frequency atomic magnetometer

    Science.gov (United States)

    Deans, Cameron; Marmugi, Luca; Hussain, Sarah; Renzoni, Ferruccio

    2016-03-01

    We report on a compact, tunable, and scalable to large arrays imaging device, based on a radio-frequency optically pumped atomic magnetometer operating in magnetic induction tomography modality. Imaging of conductive objects is performed at room temperature, in an unshielded environment and without background subtraction. Conductivity maps of target objects exhibit not only excellent performance in terms of shape reconstruction but also demonstrate detection of sub-millimetric cracks and penetration of conductive barriers. The results presented here demonstrate the potential of a future generation of imaging instruments, which combine magnetic induction tomography and the unmatched performance of atomic magnetometers.

  8. Probing Properties of Cold Radiofrequency Plasma with Polymer Probe

    CERN Document Server

    Bormashenko, Edward; Multanen, Victor

    2014-01-01

    The probe intended for the characterization of cold plasma is introduced. The probe allows estimation of the Debye length of the cold plasma. The probe is based on the pronounced modification of surface properties (wettability) of polymer films by cold plasmas. The probe was tested with the cold radiofrequency inductive air plasma discharge. The Debye length and the concentration of charge carriers were estimated for various gas pressures. The reported results coincide reasonably with the corresponding values established by other methods. The probe makes possible measurement of characteristics of cold plasmas in closed chambers.

  9. Electromagnetic induction imaging with a radio-frequency atomic magnetometer

    CERN Document Server

    Deans, Cameron; Hussain, Sarah; Renzoni, Ferruccio

    2016-01-01

    We report on a compact, tunable, and scalable to large arrays imaging device, based on a radio-frequency optically pumped atomic magnetometer operating in magnetic induction tomography modality. Imaging of conductive objects is performed at room temperature, in an unshielded environment and without background subtraction. Conductivity maps of target objects exhibit not only excellent performance in terms of shape reconstruction but also demonstrate detection of sub-millimetric cracks and penetration of conductive barriers. The results presented here demonstrate the potential of a future generation of imaging instruments, which combine magnetic induction tomography and the unmatched performance of atomic magnetometers.

  10. Temperature and salinity variability in the Greek Seas based on POSEIDON stations time series: preliminary results

    Directory of Open Access Journals (Sweden)

    D. VELAORAS

    2013-07-01

    Full Text Available Temperature and salinity time series provided by three POSEIDON monitoring stations (buoys are examined in order to study the seasonal and interannual variability of the water mass characteristics. The sites at Athos (North Aegean Sea, E1M3A (Central Cretan Sea and Pylos (Eastern Ionian Sea were chosen, as these buoys provide measurements at various depths, while they represent 3 major basins respectively. The study of the T and S characteristics reveals important seasonal changes and highlights the particular characteristics of each basin. Dense water production in the Northern Aegean is found to be hindered by the presence of the surface Black Sea Water (BSW mass. On the other hand, the intermediate water mass in the Cretan Sea is shown to be ventilated during the winter season. A significant temperature and salinity increase has been monitored over both the Central Cretan and Eastern Ionian Seas starting from the middle of 2008 and 2009 respectively. This could possibly be attributed to changes in the intermediate water masses of the Eastern Mediterranean, without ruling out the possibility of water mass exchanges between the two basins.

  11. Design of FPGA Based Neural Network Controller for Earth Station Power System

    Directory of Open Access Journals (Sweden)

    Hassen T. Dorrah

    2012-06-01

    Full Text Available Automation of generating hardware description language code from neural networks models can highly decrease time of implementation those networks into a digital devices, thus significant money savings. To implement the neural network into hardware designer, it is required to translate generated model into device structure. VHDL language is used to describe those networks into hardware. VHDL code has been proposed to implement ANNs as well as to present simulation results with floating point arithmetic of the earth station and the satellite power systems using ModelSim® PE 6.6 simulator tool. Integration between MATLAB® and VHDL is used to save execution time of computation. The results shows that a good agreement between MATLAB and VHDL and a fast/flexible feed forward NN which is capable of dealing with floating point arithmetic operations; minimum number of CLB slices; and good speed of performance. FPGA synthesis results are obtained with view RTL schematic and technology schematic from Xilinix tool. Minimum number of utilized resources is obtained by using Xilinix VERTIX5.

  12. Multiple ground-based observations at Zhongshan Station during the April/May 1998 solar events

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Simultaneous observations at Zhongshan Station, Antarctica, during May 1-7, 1998 are presented to show the responses of the polar ionosphere to the April/May 1998 solar events. One of the main geo-effects of the solar events resulted in the major magnetic storm on May 4. At the storm onset on May 2 the ionosphere F2 layer abruptly increased in altitude, the geomagnetic H-component started negative deviation and the spectral amplitude of the ULF wave intensified. Both large isolated riometer absorption and large negative deviation of the geomagnetic H-component occurred at about 0639UT. There was a time lag of about one hour and ten minutes between the storm onset and the IMF southward turning, as measured by the WIND satellite. The polar ionosphere was highly disturbed, as shown by frequent large deviations of the geomagnetic H-component, large riometer absorption events and strong ULF waves in all the courses of the storm. The absorption increased greatly causing the digisonde to be blackout most of the time. However, the data still showed a substantial decrease in the F2 electron density and oscillation of the F2 layer peak height with an amplitude exceeding 200 km.

  13. Evaluation of Annual Rainfall Erosivity Index Based on Daily, Monthly, and Annual Precipitation Data of Rainfall Station Network in Southern Taiwan

    OpenAIRE

    Ming-Hsi Lee; Huan-Hsuan Lin

    2015-01-01

    The erosivity factor in the universal soil loss equation (USLE) provides an effective means of evaluating the erosivity power of rainfall. The present study proposes three regression models for estimating the erosivity factor based on daily, monthly, and annual precipitation data of rainfall station network, respectively. The validity of the proposed models is investigated using a dataset consisting of 16,560 storm events monitored by 55 rainfall stations in southern Taiwan. The results show ...

  14. Base station MAC with APRMA protocol for broadband multimedia ATM in micro/pico-cellular mobile networks

    DEFF Research Database (Denmark)

    Le, Khanh Hoang; Nielsen, Søren Nørskov; Dittmann, Lars;

    1998-01-01

    principles and the performance of this protocol are discussed. A channel efficiency of more than 70% and a mean cell transfer delay of less than 17 cells are obtained in the range of 1-50 simultaneously connected users even with bursty traffic. For this, the cell dropping rate is kept below 10-9 when the......The concept for a wireless ATM access system that enables seamless mobile connectivity to the B-ISDN is presented. It is based on small, low cost and intelligent base stations running a medium access control (MAC) protocol using adaptive packet reservation multiple access (APRMA). Both the...... mobile terminals use buffer lengths of only 200-300 cells. The different components of this access system are currently under implementation and the MAC unit has been successfully implemented for a 32 Mbit/s wireless channel supporting 25 Mbit/s ATM introducing only 22% of protocol overhead...

  15. Placement of Base Stations in Broadband Power Line Communications Access Networks by Means of Multi-criteria Optimization

    Science.gov (United States)

    Haidine, Abdelfatteh; Lehnert, Ralf

    Broadband Power Line Communications (B-PLC) technology is an alternative for broadband access networks, allowing bit rates up to currently 200Mbps. This technique uses the wiring of the low-voltage grid in order to offer to the users the telecommunications services, such as Internet, VoIP, VoD, etc. The B-PLC design process is sub-divided into two parts: the Generalized Base Station Placement (GBSP) problem and the PLC Channel Allocation Problem (P-CAP). This paper focuses on GBSP that is modeled as multi-criteria combinatorial optimization problem. Based on our published mathematical modeling, this paper supplies more numerical experiments for the evaluation of Multi-Objective Evolutionary Algorithms (MOEAs) in solving GBSP. Their performance is compared with the single-objective optimization.

  16. Low-level radio-frequency interference detection algorithm based on European Centre for Medium-Range Weather Forecasting for Soil Moisture and Ocean Salinity

    Science.gov (United States)

    Lu, Hailiang; Li, Qingxia; Li, Yan; Li, Yinan; Li, Hao

    2015-01-01

    At present, the Soil Moisture and Ocean Salinity (SMOS) mission is severely affected by radio frequency interferences (RFIs), and the detection of low-level RFI-contamination brightness temperatures (BTs) is still a challenge in SMOS. A low-level RFI detection algorithm is proposed, which is based on the soil surface temperature products provided by the European Centre for Medium-Range Weather Forecasting. The algorithm is analyzed in terms of RFI-flagged snapshot, RFI-flagged probability, and localization accuracy. The performance of the algorithm is demonstrated by SMOS data. The results show this algorithm can detect and flag more low-level RFI-contamination BTs and show a better performance.

  17. Level of Service Analysis Based on Maximum Number of Passengers in Waiting Room of Railway Passenger Station Using Arena Simulation

    Directory of Open Access Journals (Sweden)

    Bo Yang

    2015-01-01

    Full Text Available The level of service is an important aspect of the operation and management at a railway passenger station. Particularly, the level of service in waiting room (LOSWR is one of the most important influential factors in deciding passengers’ satisfaction. This paper proposes a model for finding the LOSWR based on the maximum number of passengers, and an Arena simulation model that simulates passengers’ aggregation behaviors in the waiting room is presented for analyzing the LOSWR. Through the simulation, we demonstrate how the passenger advanced arrival time and the accompany rate influence the maximum number of passengers and the LOSWR. In addition, the simulation also illustrates the effect utilities and the priority of different measures that can be used to improve the LOSWR. In detail, the simulation results demonstrate that the passenger advanced arrival time and advanced check-out time have much stronger effect utilities on the maximum number of passengers and the LOSWR than other discussed factors. The simulation suggests that the Arena is an effective simulation platform for analyzing complex passengers-related behaviors at railway passenger station.

  18. effect of electromagnetic fields from cellular phone base stations on some physiological and biophysical properties of rats

    International Nuclear Information System (INIS)

    the hazards of exposure to EMFs are observed on different tissues, the mechanistic by which EMFs can produce such effect still need to be delineated. the present study aims to monitor the possibility of modulation in the different physiological and biophysical properties of the organs after exposure to microwave produced from mobile phone base station at frequency of 900 MHz. one hundred and ten pregnant rats were exposed for periods of 5 and 12 week's at distances of 8,15 and 25 meter from the station antenna (0.01,0.05 and 0.036 MW/cm2) the groups exposed for 5 weeks classified into two halves, one half was used for direct effect studies and the other was used for delayed effects studies (45 days post irradiation). haematological investigations demonstrated non significant changes in (RBC's), (Hb),(PCV) and (MCV)of exposed and delayed rats for 5,12 weeks. the young's of exposed rats show non considerable increase in RBC's, Hb and PCV. significant increases were observed in serum total protein , albumin and globulin levels in 5 and 12 weeks exposed rats and more significant increase in delayed rats

  19. Full-duplex radio-over-fiber system with novel source-free base station using polarization multiplexing

    International Nuclear Information System (INIS)

    A cost-effective radio-over-fiber (RoF) system with novel source-free base station (BS) has been proposed and demonstrated for the first time, by employing polarization multiplexing (PolMUX). At a central station (CS), a downlink laser output is split into two orthogonal states of polarization (SOPs) and the two SOPs are used for an intermediate frequency (IF) signal and a local oscillation (LO), respectively. At a BS, we can obtain a 5 GHz IF signal for microwave access and a baseband signal for wireline access, as well as a 60 GHz LO for up/down conversions. A downlink 65 GHz wireless signal can be generated by mixing the 5 GHz IF signal with the 60 GHz LO and meanwhile an uplink baseband signal can be achieved by mixing the uplink 60 GHz signal with the 60 GHz LO which is generated at each BS. In this system, the uplink baseband signal is modulated onto the reused optical carrier while the 60 GHz LO used for up/down conversions is remotely delivered. Therefore, there are no optical or electric sources needed in each BS which could significantly reduce the system overall cost. The results successfully verify the feasibility of the proposed RoF system

  20. A Study Comparing the Efficacy of Monopolar Radiofrequency and Glycolic Acid Peels in Facial Rejuvenation of Aging Skin Using Histopathology and Ultrabiomicroscopic Sonography (UBM – An Evidence Based Study

    Directory of Open Access Journals (Sweden)

    Deepal V. Wakade

    2016-04-01

    Full Text Available Background: Radio frequency (RF and chemical peels have been used for nonablative skin rejuvenation. Both of these cause collagen remodeling in the dermis and neo-collagen formation resulting in facial rejuvenation. There is limited literature on the evaluation of collagen remodeling by objective methods. Objective: To compare the benefits of monopolar radiofrequency and glycolic acid peels in facial rejuvenation with regards to histopathology and Ultrabiomicroscopic sonography (UBM. Methodology: In this study, forty patients with mild to moderate photoaging received four treatments with 3 weeks interval of monopolar radiofrequency on one side of face and glycolic acid peels in increasing concentrations (NeostrataR on the other side. Pre and post treatment, 2 mm biopsies were taken from both preauricular areas and Ultrasonography using a 35 MHz probe was done from outer canthus of eye and nasolabial folds from both sides of face. A blinded assessment was done to measure the increase in the grenz zone and dermal thickness. Results: In 35/40 patients there was a significant increase in the grenz zone on histopathology and decrease in subepidermal low-echogenic band (SLEB on UBM of the nasolabial folds on both sides of the face (p < 0.05. Conclusion: Radiofrequency and chemical peels showed equal efficacy in the treatment of facial rejuvenation.

  1. International Space Station as a base camp for exploration beyond low Earth orbit

    Science.gov (United States)

    Raftery, Michael; Hoffman, Jeffrey

    2013-04-01

    The idea for using the International Space Station (ISS) as a platform for exploration has matured in the past few years and the concept continues to gain momentum. ISS provides a robust infrastructure which can be used to test systems and capabilities needed for missions to the Moon, Mars, asteroids and other potential destinations. International cooperation is a critical enabler and ISS has already demonstrated successful management of a large multi-national technical endeavor. Systems and resources needed for expeditions can be aggregated and thoroughly tested at ISS before departure thus providing wide operational flexibility and the best assurance of mission success. A small part of ISS called an Exploration Platform (ISS-EP) can be placed in cislunar space providing immediate benefits and flexibility for future exploration missions. We will show how ISS and the ISS-EP can be used to reduce risk and improve the operational flexibility for missions beyond low Earth orbit. Life support systems and other technologies developed for ISS can be evolved and adapted to the ISS-EP and other exploration spacecrafts. New technology, such as electric propulsion and advanced life support systems can be tested and proven at ISS as part of an incremental development program. Commercial companies who are introducing transportation and other services will benefit with opportunities to contribute to the mission since ISS will serve as a focal point for the commercialization of low earth orbit services. Finally, we will show how the use of ISS provides immediate benefits to the scientific community because its capabilities are available today and certain critical aspects of exploration missions can be simulated.

  2. Radiofrequency catheter oblation in atrial flutter

    International Nuclear Information System (INIS)

    Objective: To evaluate the radiofrequency catheter ablation for type I atrial flutter through application of Holo catheter labelling with anatomic imaging localization to ablate the isthmus of IVCTA during complete double-way block. Methods: Eleven cases with type I atrial flutter undergone Holo catheter labelling technique and consecution with conduction time change of coronary venous sinus orifice with-right atrial lower lateral wall pace excitation, were performed with radiofrequency catheter ablation for the isthmus outcoming with complete double-way conduction block. Results: All together 11 cases with 4 of atrial flutter and 7 of sinus rhythm were undergone radiofrequency catheter ablation resulting with double-way conduction block of the isthmus accompanied by prolongation of right atrial conduction time 56.0 ± 2.3 ms and 53.0 ± 4.6 ms respectively. The right atrial excitation appeared to be in clockwise and counter-clockwise of single direction. No recurrence occurred during 3-34 months follow up with only one showing atrial fibrillation. Conclusions: The application of Holo catheter labelling technique with anatomic imaging localization to achieve the double-way conduction block by radiofrequency catheter ablation of TVC-TA isthmus, is a reliable method for treating atrial flutter

  3. 78 FR 25916 - Authorization of Radiofrequency Equipment

    Science.gov (United States)

    2013-05-03

    ... of 1998, 63 FR 36591, July 7, 1998, the Commission reduced and consolidated the equipment approval...). See Electronic Filing of Documents in Rulemaking Proceedings, 63 FR 24121 (1998). Electronic Filers... COMMISSION 47 CFR Parts 0, 2, 15 and 68 Authorization of Radiofrequency Equipment AGENCY:...

  4. Managing turbinate hypertrophy: coblation vs. radiofrequency treatment.

    Science.gov (United States)

    Passali, D; Loglisci, M; Politi, L; Passali, G C; Kern, E

    2016-06-01

    The role of inferior turbinate hypertrophy in the reduction of nasal airflow is well established. Although chronic nasal obstruction is not life- threatening, it significantly impairs patients' quality of life, affecting many aspects of daily activities; therefore, patients seek medical intervention. 40 patients were selected (27 males and 13 females) between 27 and 64 years of age with a symptom of nasal obstruction. The patients were divided in two groups: Group 1: coblation, 25 patients (18 males and 7 females); Group 2: radiofrequency, 15 patients (7 males and 6 females). These 40 patients were followed for 3 years. Patients were analyzed using both subjective and objective methods. The visual analog scale (VAS) subjective data and objective data including both active anterior rhinomanometry and acoustic rhinometry were recorded and analyzed. Data were collected pre-operatively and at 1 and 3 years post-operatively. According to our data, both coblation and radiofrequency turbinate reduction benefit patients with good results. The complications, found during the follow-up, are limited to minimal bleeding and crusting. Coblation and radiofrequency were significantly less painful than others procedures during the early post-operative period. In our study, both coblation and radiofrequency provide an improvement in nasal airflow with a reduction in nasal obstructive symptoms in the short term, but their efficacy tended to decrease within 3 years. PMID:26321749

  5. Interactions between radiofrequency signals and living organisms

    International Nuclear Information System (INIS)

    This dossier is composed of 13 articles dealing with the interactions between radio-frequencies and living organisms. It is an overview of various scientific approaches to the field and is of interest for all citizens as the use of mobile phones is widely spread. In the first article it is shown how a model has been built to assess the distribution of the whole body exposure of the population. The second article reviews the state of the art in personal exposure measurements at radio-frequencies. The third article shows that the knowledge of the mechanism of action by which exposure increases the risk of health hazards is necessary. The fourth article shows that individual neuro-psychic factors take a prominent but maybe not unique, part in electromagnetic hypersensitivity. The fifth article shows that no evidence was found to link health disturbances of electromagnetic hypersensitive individuals with radiofrequency exposure. The sixth article shows that the wireless phone is not an athermal hazard to the brain. The seventh article shows that the in utero and post-natal exposure to Wi-Fi does not damage the brains of young rats. The eighth article concludes that recent studies provide no convincing proof of deleterious effects of radiofrequency exposure on the integrity of the blood-brain barrier for specific absorption rates up to 6 W/kg. The ninth article shows that no co-genotoxic effect of radiofrequency was found at levels of exposure that did not induce heating. The tenth article confirms that industry-sponsored studies were least likely to report results suggesting effects. The last article shows that general practitioners are increasingly questioned by their patients about the issue of electromagnetic waves. (A.C.)

  6. Operation and maintenance experience with computer based systems of Nuclear Power Plant - Kaiga Generating Station-1 and 2

    International Nuclear Information System (INIS)

    Many computerized systems like PDCS, CCTMS, BMS, COIS have been introduced for the first time in NPCIL at KGS. As these systems were new and more sophisticated compared to the equivalent systems at earlier plants, problems and challenges encountered during operation and maintenance were many and different of its kind. As the technology update in the IT field is fast, obsoleteness of the hardware and software poses a threat to the system availability and maintenance which remains a great concern in a Nuclear Power Plant. This paper gives details of the major problems resolved and steps taken for a trouble free operation of some computer based systems at Kaiga Generating Station 1 and 2. (author)

  7. Exposure of farm workers to electromagnetic radiation from cellular network radio base stations situated on rural agricultural land.

    Science.gov (United States)

    Pascuzzi, Simone; Santoro, Francesco

    2015-01-01

    The electromagnetic field (EMF) levels generated by mobile telephone radio base stations (RBS) situated on rural-agricultural lands were assessed in order to evaluate the exposure of farm workers in the surrounding area. The expected EMF at various distances from a mobile telephone RBS was calculated using an ad hoc numerical forecast model. Subsequently, the electric fields around some RBS on agricultural lands were measured, in order to obtain a good approximation of the effective conditions at the investigated sites. The viability of this study was tested according to the Italian Regulations concerning general and occupational public exposure to time-varying EMFs. The calculated E-field values were obtained with the RBS working constantly at full power, but during the in situ measurements the actual power emitted by RBS antennas was lower than the maximum level, and the E-field values actually registered were much lower than the calculated values. PMID:26647953

  8. Data reduction and tying in regional gravity surveys—results from a new gravity base station network and the Bouguer gravity anomaly map for northeastern Mexico

    Science.gov (United States)

    Hurtado-Cardador, Manuel; Urrutia-Fucugauchi, Jaime

    2006-12-01

    Since 1947 Petroleos Mexicanos (Pemex) has conducted oil exploration projects using potential field methods. Geophysical exploration companies under contracts with Pemex carried out gravity anomaly surveys that were referred to different floating data. Each survey comprises observations of gravity stations along highways, roads and trails at intervals of about 500 m. At present, 265 separate gravimeter surveys that cover 60% of the Mexican territory (mainly in the oil producing regions of Mexico) are available. This gravity database represents the largest, highest spatial resolution information, and consequently has been used in the geophysical data compilations for the Mexico and North America gravity anomaly maps. Regional integration of gravimeter surveys generates gradients and spurious anomalies in the Bouguer anomaly maps at the boundaries of the connected surveys due to the different gravity base stations utilized. The main objective of this study is to refer all gravimeter surveys from Pemex to a single new first-order gravity base station network, in order to eliminate problems of gradients and spurious anomalies. A second objective is to establish a network of permanent gravity base stations (BGP), referred to a single base from the World Gravity System. Four regional loops of BGP covering eight States of Mexico were established to support the tie of local gravity base stations from each of the gravimeter surveys located in the vicinity of these loops. The third objective is to add the gravity constants, measured and calculated, for each of the 265 gravimeter surveys to their corresponding files in the Pemex and Instituto Mexicano del Petroleo database. The gravity base used as the common datum is the station SILAG 9135-49 (Latin American System of Gravity) located in the National Observatory of Tacubaya in Mexico City. We present the results of the installation of a new gravity base network in northeastern Mexico, reference of the 43 gravimeter surveys

  9. Risk-based inservice testing program modifications at Palo Verde nuclear generating station

    Energy Technology Data Exchange (ETDEWEB)

    Knauf, S.; Lindenlaub, B.; Linthicum, R.

    1996-12-01

    Arizona Public Service Company (APS) is investigating changes to the Palo Verde Inservice Testing (IST) Program that are intended to result in the reduction of the required test frequency for various valves in the American Society of Mechanical Engineers (ASME) Section XI IST program. The analytical techniques employed to select candidate valves and to demonstrate that these frequency reductions are acceptable are risk based. The results of the Palo Verde probabilistic risk assessment (PRA), updated in June 1994, and the risk significant determination performed as part of the implementation efforts for 10 CFR 50.65 (the maintenance rule) were used to select candidate valves for extended test intervals. Additional component level evaluations were conducted by an `expert panel.` The decision to pursue these changes was facilitated by the ASME Risk-Based Inservice Testing Research Task Force for which Palo Verde is participating as a pilot plant. The NRC`s increasing acceptance of cost beneficial licensing actions and risk-based submittals also provided incentive to seek these changes. Arizona Public Service is pursuing the risk-based IST program modification in order to reduce the unnecessary regulatory burden of the IST program through qualitative and quantitative analysis consistent with maintaining a high level of plant safety. The objectives of this project at Palo Verde are as follows: (1) Apply risk-based technologies to IST components to determine their risk significance (i.e., high or low). (2) Apply a combination of deterministic and risk-based methods to determine appropriate testing requirements for IST components including improvement of testing methods and frequency intervals for high-risk significant components. (3) Apply risk-based technologies to high-risk significant components identified by the {open_quotes}expert panel{close_quotes} and outside of the IST program to determine whether additional testing requirements are appropriate.

  10. Simulation of Air flow, Smoke Dispersion and Evacuation of the Monument Metro Station based on Subway Climatology

    OpenAIRE

    Qian, Zi; Agnew, Brian; Thompson, Emine Mine

    2014-01-01

    This research is creating a working laboratory in Newcastle Monument metro station to understand the details of how the over ground climate influences the internal airflow and the impact this has on evacuation strategies. It is intended to link weather data with the background air flow in the station and identify the main driving forces for the dispersion of smoke or toxic agents throughout the station. The subway air flow will be evaluated and then interfaced with a VR simulation of the stat...

  11. Radiofrequency electromagnetic field exposure and non-specific symptoms of ill health: A systematic review

    International Nuclear Information System (INIS)

    This article is a systematic review of whether everyday exposure to radiofrequency electromagnetic field (RF-EMF) causes symptoms, and whether some individuals are able to detect low-level RF-EMF (below the ICNIRP [International Commission on Non-Ionizing Radiation Protection] guidelines). Peer-reviewed articles published before August 2007 were identified by means of a systematic literature search. Meta-analytic techniques were used to pool the results from studies investigating the ability to discriminate active from sham RF-EMF exposure. RF-EMF discrimination was investigated in seven studies including a total of 182 self-declared electromagnetic hypersensitive (EHS) individuals and 332 non-EHS individuals. The pooled correct field detection rate was 4.2% better than expected by chance (95% CI: -2.1 to 10.5). There was no evidence that EHS individuals could detect presence or absence of RF-EMF better than other persons. There was little evidence that short-term exposure to a mobile phone or base station causes symptoms based on the results of eight randomized trials investigating 194 EHS and 346 non-EHS individuals in a laboratory. Some of the trials provided evidence for the occurrence of nocebo effects. In population based studies an association between symptoms and exposure to RF-EMF in the everyday environment was repeatedly observed. This review showed that the large majority of individuals who claims to be able to detect low level RF-EMF are not able to do so under double-blind conditions. If such individuals exist, they represent a small minority and have not been identified yet. The available observational studies do not allow differentiating between biophysical from EMF and nocebo effects

  12. Station Adler railway terminal structures modelling taking into account seismic base isolation

    Directory of Open Access Journals (Sweden)

    Ye.A. Belugina

    2012-02-01

    Full Text Available The article discusses methods of building frame constructions modeling by finite element method, taking into account seismic isolation systems. It presents data of the calculation in the two software systems. The calculation results are compared by analyzing of the individual elements stress-strain state. Recommendations about the calculation schemes and software systems selection are given on the base of results analyzing. The achieved results allow us to evaluate the effectiveness of seismic base isolation and can be used for wide application of such systems in building area.

  13. Implementing a spinosad-based local bait station to control Bactrocera cucurbitae (Diptera: Tephritidae) in high rainfall areas of Reunion Island.

    Science.gov (United States)

    Delpoux, Camille; Deguine, Jean-Philippe

    2015-01-01

    Three species of fruit flies cause serious damage to cucurbit crops on Reunion Island: Bactrocera cucurbitae (Diptera: Tephritidae) (Coquillett 1899), Dacus ciliatus (Loew 1901), and Dacus demmerezi (Bezzi 1917). To control them, a program of agroecological management of cucurbit flies has been implemented based on the application of Synéis-appât, especially spot sprays on corn borders. However, the high rainfall on Reunion Island limits the long-term efficiency of the bait; in addition, this method cannot be used for large chayote trellises, because corn borders cannot be planted around them. The aim of this study was to design a bait station adapted to prevailing conditions on Reunion Island. An 'umbrella trap' tested in Taiwan was used as a reference to compare its efficacy with our local bait station. Experiments were conducted in field cages on B. cucurbitae to test different characteristics of bait stations and to construct one using local materials. Results were validated in the field. The attractiveness of the bait station was related mainly to the color of the external surface, yellow being the most attractive color. The efficacy of the bait station with respect to fly mortality was found to be linked to the accessibility of the bait, and direct application of Synéis-appât on the bait station was found to be the most efficient. In the field, B. cucurbitae were more attracted to the local bait station than to the umbrella trap, while the two other fly species displayed equal attraction to both trap types. Our local bait station is a useful alternative to spot sprays of Synéis-appât and is now included in a local pest management program and is well accepted by farmers. PMID:25688089

  14. Woody biomass-based bioenergy development at the Atikokan Power Generating Station: Local perceptions and public opinions

    Science.gov (United States)

    Baten, Cassia Sanzida

    To tackle climate change, reduce air pollution and promote development of renewable energy, the Ontario government is investing in the conversion of the coal-based Atikokan Power Generating Station (APGS) in Atikokan, Ontario, to woody biomass feedstock. This research offers one of the first looks at the perspectives of different individuals and groups on converting woody biomass to energy. Using a combination of study instruments which include literature review, surveys, interviews with key informants, semi-structured interviews, and focus group discussions, this dissertation uses qualitative research to provide a picture of the public's opinions and attitudes towards the APGS biomass energy development. Given Ontario's huge and sustainably managed forest resource, woody biomass is expected to be a major component of renewable energy production in Ontario. The move towards renewable energy that replaces fossil fuels with woody biomass will have considerable socio-economic implications for local and First Nation communities living in and around the bioenergy power generating station. Findings indicate that there is wide support for biomass utilization at the APGS by local people, especially since the project would create sustainable employment. The connection of woody biomass-based energy generation and rural community development provides opportunities and challenges for Atikokan's economic development. Respondents identified economic, environmental and social barriers to biomass utilization, and emphasized trust and transparency as key elements in the successful implementation of the APGS project. As demand for woody biomass-based energy increases, special attention will be needed to ensure and maintain the social, economic and environmental sustainability of biomass use at the APGS. In this research, respondents' views about biomass utilization for energy mainly focused on forest-related issues rather than energy. In Atikokan much of the project's social

  15. Comparison of total ozone and erythemal UV data from OMI with ground-based measurements at Rome station

    Directory of Open Access Journals (Sweden)

    I. Ialongo

    2008-02-01

    Full Text Available Ground-based total ozone and surface UV irradiance measurements have been collected since 1992 using Brewer spectrophotometer and Erythemal Dose Rates (EDRs have been determined by a broad-band radiometer (model YES UVB-1 operational since 2000 at Rome station. The methodology to retrieve the EDR and the Erythemal Daily Dose (EDD from the radiometer observations is described. Ground-based measurements were compared with satellite-derived total ozone and UV data from the Ozone Monitoring Instrument (OMI. OMI, onboard the NASA EOS Aura spacecraft, is a nadir viewing spectrometer that provides total ozone and surface UV retrievals. The results of the validation exercise showed satisfactory agreement between OMI and Brewer total ozone data, for both OMI-TOMS and OMI-DOAS ozone alghorithms (biases of −1.8% and −0.7%, respectively. Regarding UV data, OMI data overestimate ground-based erythemally weighted data retrieved from both Brewer and YES Radiometer (biases about 20%, probably because of the effect of absorbing aerosols in an urban site such as Rome.

  16. Station Adler railway terminal structures modelling taking into account seismic base isolation

    OpenAIRE

    Ye.A. Belugina; Ye.V. Rumyantsev

    2012-01-01

    The article discusses methods of building frame constructions modeling by finite element method, taking into account seismic isolation systems. It presents data of the calculation in the two software systems. The calculation results are compared by analyzing of the individual elements stress-strain state. Recommendations about the calculation schemes and software systems selection are given on the base of results analyzing. The achieved results allow us to evaluate the effectiveness of seismi...

  17. The Public Safety Broadband Network: A Novel Architecture with Mobile Base Stations

    OpenAIRE

    Chen, Xu; Guo, Dongning; Grosspietsch, John

    2013-01-01

    A nationwide interoperable public safety broadband network is being planned by the United States government. The network will be based on long term evolution (LTE) standards and use recently designated spectrum in the 700 MHz band. The public safety network has different objectives and traffic patterns than commercial wireless networks. In particular, the public safety network puts more emphasis on coverage, reliability and latency in the worst case scenario. Moreover, the routine public safe...

  18. 78 FR 13895 - Certain Wireless Communications Base Stations and Components Thereof; Institution of...

    Science.gov (United States)

    2013-03-01

    ...Notice is hereby given that a complaint was filed with the U.S. International Trade Commission on January 24, 2013, under section 337 of the Tariff Act of 1930, as amended, 19 U.S.C. 1337, on behalf of Adaptix, Inc. of Carrolton, Texas. The complaint alleges violations of section 337 based upon the importation into the United States, the sale for importation, and the sale within the United......

  19. Phosphorylation and gene expression of p53 are not affected in human cells exposed to 2.1425 GHz band CW or W-CDMA modulated radiation allocated to mobile radio base stations.

    Science.gov (United States)

    Hirose, H; Sakuma, N; Kaji, N; Suhara, T; Sekijima, M; Nojima, T; Miyakoshi, J

    2006-09-01

    A large-scale in vitro study focusing on low-level radiofrequency (RF) fields from mobile radio base stations employing the International Mobile Telecommunication 2000 (IMT-2000) cellular system was conducted to test the hypothesis that modulated RF fields induce apoptosis or other cellular stress response that activate p53 or the p53-signaling pathway. First, we evaluated the response of human cells to microwave exposure at a specific absorption rate (SAR) of 80 mW/kg, which corresponds to the limit of the average whole-body SAR for general public exposure defined as a basic restriction by the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines. Second, we investigated whether continuous wave (CW) and wideband code division multiple access (W-CDMA) modulated signal RF fields at 2.1425 GHz induced apoptosis or any signs of stress. Human glioblastoma A172 cells were exposed to W-CDMA radiation at SARs of 80, 250, and 800 mW/kg, and CW radiation at 80 mW/kg for 24 or 48 h. Human IMR-90 fibroblasts from fetal lungs were exposed to both W-CDMA and CW radiation at a SAR of 80 mW/kg for 28 h. Under the RF field exposure conditions described above, no significant differences in the percentage of apoptotic cells were observed between the test groups exposed to RF signals and the sham-exposed negative controls, as evaluated by the Annexin V affinity assay. No significant differences in expression levels of phosphorylated p53 at serine 15 or total p53 were observed between the test groups and the negative controls by the bead-based multiplex assay. Moreover, microarray hybridization and real-time RT-PCR analysis showed no noticeable differences in gene expression of the subsequent downstream targets of p53 signaling involved in apoptosis between the test groups and the negative controls. Our results confirm that exposure to low-level RF signals up to 800 mW/kg does not induce p53-dependent apoptosis, DNA damage, or other stress response in human

  20. Research On Coagulation Zone Prediction Induced By Cooled-tip Radiofrequency Ablation Base On The BP Neural Network%基于BP神经网络的冷极射频消融凝固灶预测研究

    Institute of Scientific and Technical Information of China (English)

    郑丹平; 朱名日; 刘文彬; 姚鑫; 潘凯

    2014-01-01

    射频消融过程非常复杂,它的疗效影响因素多且关系复杂。在冷极射频消融仪治疗肿瘤过程中,射频输出功率和循环水泵转速起着重要作用。为扩大消融范围,达到一次性灭活肿瘤细胞,在治疗前,需选择适当的治疗参数。将BP神经网络模型引入射频消融中,建立冷极射频消融凝固灶预测的模型,并对效果进行检验。结果表明:检验样本中消融凝固灶与实际值的线性相关系数为0.988。针对消融横径,其相对误差的平均值为0.01。该模型对射频消融参数设置起到一定的支持作用,具有一定的实际参考价值。%The process of radiofrequency ablation is very complicated, there are many factors to influence the ef-fect and the relation is complex. The power output by RF and circulating pump speed plays an important role in the process of treatment by cooled-tip RFA. To expand the scope of ablation, the appropriate parameters should be se-lected to achieve one-time inactivated tumor cells before treatment. The BP neural network is introduced in the radiofrequency ablation. A model of coagulation zone prediction induced by cooled-tip radiofrequency ablation is built. The results show that the test sample correlation coefficient of linear ablation lesion and actual value is 0.988. For ablation diameter, the average value of the relative error is 0.01.The model plays a supporting role on parameter setting of radiofrequency ablation, which has some practical value.

  1. Space station/base food system study. Volume 1: Systems design handbook

    Science.gov (United States)

    1970-01-01

    A description is given of the approach used in a study to identify and define engineering data for a spectrum of possible items and equipment comprising potential food systems. In addition, the material presented includes: (1) the study results containing the candidate concepts considered and technical data, performance characteristics, and sketches for each of the concepts by functional area; (2) human factors considerations for crew tasks; (3) shuttle supply interface requirements; (4) special food system study areas; and (5) recommendations and conclusions based on the study results.

  2. Fraxelated radiofrequency device for acne scars

    Science.gov (United States)

    Rao, Babar K.; Khokher, Sairah

    2012-09-01

    Acne scars can be improved with various treatments such as topical creams, chemical peels, dermal fillers, microdermabrasion, laser, and radiofrequency devices. Some of these treatments especially lasers and deep chemical peels can have significant side effects such as post inflammatory hyperpigmentation in darker skin types. Fraxelated RF Laser devices have been reported to have lower incidence of side effects in all skin phototypes. Nine patients between ages 18 and 35 of various skin phototypes were selected from a private practice and treated with a RF fraxelated device (E-matrix) for acne scars. Outcomes were measured by physician observation, subjective feedback received by patients, and comparison of before and after photographs. In this small group of patients with various skin phototypes, fraxelated radiofrequency device improved acne scars with minimal side effects and downtime.

  3. GIS-Based Analysis of the Location of Filling Stations in Metropolitan Kano against the Physical Planning Standards

    Directory of Open Access Journals (Sweden)

    M.U. Mohammed

    2014-09-01

    Full Text Available This paper analysed the location of filling stations in Kano Metropolis against the physical planning standards set by Department of Petroleum Resource, DPR (2007 and Kano Urban Planning and Development Agency, KNUPDA (2013. Names and street addresses of the filling stations were obtained from the Department Petroleum Resource (DPR Kano Office. Global positioning System Garmin 76X GPS was used to capture the location of the filling station. The quickbird imagery, street map, and boundary map were obtained from the Kano State Ministry of Land and Physical planning. The data were imported to Arcmap environment of ArcGIS 10, integrated and georefrenced to the same coordinate system. All the analyses were performed in the Arcmap environment using spatial statistics, spatial analyst and proximity tools available in the software. The findings revealed that there 214 filling station located along the 43 roads in the study area, of which 69% are owned by independent marketers, 26% owned by Major Marketers and 5% owned by the NNPC. Most of the station satisfied the minimum requirement of 15 metre distance from the road (96%. Equally 98% of the filling stations met the minimum distance of 100 meter from the health care facilities. However many station had not meet the criteria of 400 meter minimum distance to other stations where located on same road side and when not separated by any road or street. The research finally concludes that regulatory agencies need to look into the issue and take appropriate measures.

  4. Full-duplex radio over fiber link with colorless source-free base station based on single sideband optical mm-wave signal with polarization rotated optical carrier

    Science.gov (United States)

    Ma, Jianxin

    2016-07-01

    A full-duplex radio-over fiber (RoF) link scheme based on single sideband (SSB) optical millimeter (mm)-wave signal with polarization-rotated optical carrier is proposed to realize the source-free colorless base station (BS), in which a polarization beam splitter (PBS) is used to abstract part of the optical carrier for conveying the uplink data. Since the optical carrier for the uplink does not bear the downlink signal, no cross-talk from the downlink contaminates the uplink signal. The simulation results demonstrate that both down- and up-links maintain good performance. The mm-wave signal distribution network based on the proposed full duplex fiber link scheme can use the uniform source-free colorless BSs, which makes the access system very simpler.

  5. Stochastic-based fuzzy risk assessment of SO2 emission from a power station

    International Nuclear Information System (INIS)

    Electricity production from fossil-fuel power plants is one of the main sources of air pollution. Risk assessment is a significant component for power plant air emission management. The most important output from risk assessment is the capacity to provide the basis of a decision-making process. The results of such decisions should be presented to environmental managers and the public in plain language rather than complex calculations. Uncertainty is inherent in any environmental risk assessment, and has 2 main origins, notably stochastic and cognitive. Research is under way to explore techniques that can incorporate these 2 kinds of uncertainties into the assessment process. The probability theory, or Monte Carlo simulation, is commonly used for stochastic uncertainties, while the possibilistic theory, or fuzzy logic, is used for cognitive uncertainties. In this study, a stochastic-based fuzzy risk assessment method was developed for a risk assessment of ambient air quality. The objective was to accurately predict contaminant transport and fate in ambient air and effectively assess the associated environmental and health risks. The proposed stochastic-based fuzzy risk assessment model was able to systematically quantify both probabilistic and possibilistic uncertainties associated with terrain conditions, environmental guidelines, and health criteria in air quality management systems. The results obtained from the improved simulation, uncertainty analysis and risk assessment are expected to provide more realistic decision support and bring significant environmental and economic benefits. 27 refs., 2 tabs., 7 figs.

  6. Electromagnetic limits to radiofrequency (RF) neuronal telemetry

    OpenAIRE

    Diaz, R.E.; Sebastian, T.

    2013-01-01

    The viability of a radiofrequency (RF) telemetry channel for reporting individual neuron activity wirelessly from an embedded antenna to an external receiver is determined. Comparing the power at the transmitting antenna required for the desired Channel Capacity, to the maximum power that this antenna can dissipate in the body without altering or damaging surrounding tissue reveals the severe penalty incurred by miniaturization of the antenna. Using both Specific Absorption Rate (SAR) and the...

  7. Standard guidelines for electrosurgery with radiofrequency current

    OpenAIRE

    Mutalik Sharad

    2009-01-01

    Definition: Radiofrequency (RF) induces thermal destruction of the targeted tissue by an electrical current at a frequency of 0.5 MHz (RF). As the electrode tip is not heated, there is minimal thermal damage to the surrounding tissues, producing good esthetic results. Therefore, RF ablation is also known as cold ablation or "coblation." Modality: It has three modes of operation: (a) Cut, (b) cut and coagulate and (c) coagulate. Therefore, it can be used for various purposes like incision, ...

  8. Photoacoustic Characterization of Radiofrequency Ablation Lesions

    OpenAIRE

    Bouchard, Richard; Dana, Nicholas; Di Biase, Luigi; Natale, Andrea; Emelianov, Stanislav

    2012-01-01

    Radiofrequency ablation (RFA) procedures are used to destroy abnormal electrical pathways in the heart that can cause cardiac arrhythmias. Current methods relying on fluoroscopy, echocardiography and electrical conduction mapping are unable to accurately assess ablation lesion size. In an effort to better visualize RFA lesions, photoacoustic (PA) and ultrasonic (US) imaging were utilized to obtain co-registered images of ablated porcine cardiac tissue. The left ventricular free wall of fresh ...

  9. Applications of power beaming from space-based nuclear power stations

    International Nuclear Information System (INIS)

    Power beaming from space-based reactor systems is examined using an advanced compact, lightweight Rotating Bed Reactor (RBR). Closed Brayton power conversion efficiencies in the range of 30 to 40% can be achieved with turbines, with reactor exit temperatures on the order of 20000K and a liquid drop radiator to reject heat at temperatures of approx. 5000K. Higher RBR coolant temperatures (up to approx. 30000K) are possible, but gains in power conversion efficiency are minimal, due to lower expander efficiency (e.g., a MHD generator). Two power beaming applications are examined - laser beaming to airplanes and microwave beaming to fixed ground receivers. Use of the RBR greatly reduces system weight and cost, as compared to solar power sources. Payback times are a few years at present prices for power and airplane fuel

  10. Cooled Radiofrequency Ablation for Bilateral Greater Occipital Neuralgia

    OpenAIRE

    Tiffany Vu; Akhil Chhatre

    2014-01-01

    This report describes a case of bilateral greater occipital neuralgia treated with cooled radiofrequency ablation. The case is considered in relation to a review of greater occipital neuralgia, continuous thermal and pulsed radiofrequency ablation, and current medical literature on cooled radiofrequency ablation. In this case, a 35-year-old female with a 2.5-year history of chronic suboccipital bilateral headaches, described as constant, burning, and pulsating pain that started at the subocci...

  11. In situ measurements of radiofrequency exposure levels in Greece from 2008 to 2013: a multi-parametric annual analysis.

    Science.gov (United States)

    Christopoulou, Maria; Karabetsos, Efthymios

    2015-04-01

    From 2008 through 2013, more than 6,000 in situ frequency selective audits, in the proximity of base stations, were conducted throughout Greece by the Greek Atomic Energy Commission (EEAE), in order to verify exposure limit compliance. EEAE is the competent national authority for protection of the general public against artificially produced non-ionizing radiation. This paper presents the first post processing and multi-parametric year statistical analysis of in situ measurement data corresponding to 4,705 audits in the whole country, compared to general public exposure levels, according to Greek legislation. The aim is to derive nationwide conclusions for the characterization of general public exposure to radiofrequency electromagnetic fields, during the last 6 years. The results' presentation includes electric field exposure ratios referring to broadband and frequency selective measurements at the highest exposure measurement point. Statistical analysis is applied to assist the data presentation and evaluation, based on selected criteria and classification parameters, including: (i) year (2008-2013); (ii) environment (urban/suburban/rural); (iii) frequency bands of selected common telecommunication services (e.g., TV, FM, GSM, DCS, UMTS); and (iv) number of service providers installed at the same site. In general, measurement results revealed that the vast majority of exposure values were below reference levels for general public exposure, as defined by Greek legislation. Data are constantly updated with the latest measurements, including emerging wireless technologies. PMID:25726724

  12. Rock Burst Intensity Classification Based on the Radiated Energy with Damage Intensity at Jinping II Hydropower Station, China

    Science.gov (United States)

    Chen, Bing-Rui; Feng, Xia-Ting; Li, Qing-Peng; Luo, Ru-Zhou; Li, Shaojun

    2015-01-01

    Based on the radiated energy of 133 rock bursts monitored by a microseismic technique at the Jinping II hydropower station, in Sichuan province, China, we analyzed the advantages and disadvantages of qualitative classification methods for the rock burst intensity. Then, we investigated the characteristics, magnitude, and laws of the radiated energy, as well as the relationship between the rock burst radiated energy and intensity. Then, we selected the energy as an evaluation index for the rock burst intensity classification, and proposed a new rock burst intensity quantitative classification method, which utilized the hierarchical clustering analysis technique with the complete-linkage method. Next, we created a new set of criteria for the quantitative classification of the rock burst intensity based on radiated energy and surrounding rock damage severity. The new criteria classified the rock burst intensity into five levels: extremely intense, intense, moderate, weak, and none, and the common logarithms of the radiated energy of each level were >7 lg( E/J), >4 lg( E/J) and 2 lg( E/J) and 1 lg( E/J) and <2 lg( E/J), and <1 lg( E/J), respectively. Finally, we investigated the factors influencing the classification, and verified its feasibility and applicability via several practical rock burst examples.

  13. An improved procedure to accurately assess the variability of the exposure to electromagnetic radiation emitted by GSM base station antennas

    International Nuclear Information System (INIS)

    Long-term human exposure around Global System for Mobile Communications (GSM) base station antennas has not yet been precisely established; this is of interest from human health and epidemiological perspectives. Actual exposure is difficult to assess accurately, mainly because there is a lack of technical information directly from the GSM operators. The in situ measurement standards available at present provide only a worst-case prediction method; the present work goes beyond this and proposes a methodology that, without the need for data from operators, allows a reliable way to express real exposure with a greater accuracy than all other methods proposed to date. The method is based on dual measurements of the signal strengths in the frequency domain and the time domain and takes into consideration the instantaneous traffic in GSM channels. In addition, it allows a channel-individualized exposure assessement, by making possible the separate analysis of the electric field level in the two types of channel of the GSM standard—the traffic channels and the control channels. (paper)

  14. Radio Capacity Estimation for Millimeter Wave 5G Cellular Networks Using Narrow Beamwidth Antennas at the Base Stations

    Directory of Open Access Journals (Sweden)

    AlMuthanna Turki Nassar

    2015-01-01

    Full Text Available This paper presents radio frequency (RF capacity estimation for millimeter wave (mm-wave based fifth-generation (5G cellular networks using field-level simulations. It is shown that, by reducing antenna beamwidth from 65° to 30°, we can enhance the capacity of mm-wave cellular networks roughly by 3.0 times at a distance of 220 m from the base station (BS. This enhancement is far much higher than the corresponding enhancement of 1.2 times observed for 900 MHz and 2.6 GHz microwave networks at the same distance from the BS. Thus the use of narrow beamwidth transmitting antennas has more pronounced benefits in mm-wave networks. Deployment trials performed on an LTE TDD site operating on 2.6 GHz show that 6-sector site with 27° antenna beamwidth enhances the quality of service (QoS roughly by 40% and more than doubles the overall BS throughput (while enhancing the per sector throughput 1.1 times on average compared to a 3-sector site using 65° antenna beamwidth. This agrees well with our capacity simulations. Since mm-wave 5G networks will use arbitrary number of beams, with beamwidth much less than 30°, the capacity enhancement expected in 5G system when using narrow beamwidth antennas would be much more than three times observed in our simulations.

  15. Agent-based station for on-line diagnostics by self-adaptive laser Doppler vibrometry

    Science.gov (United States)

    Serafini, S.; Paone, N.; Castellini, P.

    2013-12-01

    A self-adaptive diagnostic system based on laser vibrometry is proposed for quality control of mechanical defects by vibration testing; it is developed for appliances at the end of an assembly line, but its characteristics are generally suited for testing most types of electromechanical products. It consists of a laser Doppler vibrometer, equipped with scanning mirrors and a camera, which implements self-adaptive bahaviour for optimizing the measurement. The system is conceived as a Quality Control Agent (QCA) and it is part of a Multi Agent System that supervises all the production line. The QCA behaviour is defined so to minimize measurement uncertainty during the on-line tests and to compensate target mis-positioning under guidance of a vision system. Best measurement conditions are reached by maximizing the amplitude of the optical Doppler beat signal (signal quality) and consequently minimize uncertainty. In this paper, the optimization strategy for measurement enhancement achieved by the down-hill algorithm (Nelder-Mead algorithm) and its effect on signal quality improvement is discussed. Tests on a washing machine in controlled operating conditions allow to evaluate the efficacy of the method; significant reduction of noise on vibration velocity spectra is observed. Results from on-line tests are presented, which demonstrate the potential of the system for industrial quality control.

  16. Mortality by neoplasia and cellular telephone base stations in the Belo Horizonte municipality, Minas Gerais state, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Dode, Adilza C., E-mail: adilzadode@terra.com.br [Minas Methodist University Center Izabela Hendrix, Belo Horizonte City, Minas Gerais State (Brazil); Municipal Government of Belo Horizonte, Municipal Health Department, Belo Horizonte City, Minas Gerais State (Brazil); MRE Engenharia (Electromagnetic Radiations Measurement-Engineering), Belo Horizonte City, Minas Gerais State (Brazil); Leao, Monica M.D., E-mail: monica@desa.ufmg.br [UFMG-Universidade Federal de Minas Gerais-Belo Horizonte, Environmental and Sanitary Engineering Department, Belo Horizonte City, Minas Gerais State (Brazil); Tejo, Francisco de A.F. [UFCG-Universidade Federal de Campina Grande, Center of Electrical Engineering and Informatics, Academic Unit of Electrical Engineering, Paraiba State (Brazil); Gomes, Antonio C.R. [MRE Engenharia (Electromagnetic Radiations Measurement-Engineering), Belo Horizonte City, Minas Gerais State (Brazil); Dode, Daiana C. [MRE Engenharia (Electromagnetic Radiations Measurement-Engineering), Belo Horizonte City, Minas Gerais State (Brazil); Faculty of Medical Sciences, Medicine-Belo Horizonte, Belo Horizonte City, Minas Gerais State (Brazil); Dode, Michael C. [MRE Engenharia (Electromagnetic Radiations Measurement-Engineering), Belo Horizonte City, Minas Gerais State (Brazil); Moreira, Cristina W.; Condessa, Vania A.; Albinatti, Claudia [Municipal Government of Belo Horizonte, Municipal Health Department, Belo Horizonte City, Minas Gerais State (Brazil); Caiaffa, Waleska T. [UFMG-Universidade Federal de Minas Gerais-Belo Horizonte, Urban Health Observatory, Belo Horizonte City, Minas Gerais State (Brazil)

    2011-09-01

    Pollution caused by the electromagnetic fields (EMFs) of radio frequencies (RF) generated by the telecommunication system is one of the greatest environmental problems of the twentieth century. The purpose of this research was to verify the existence of a spatial correlation between base station (BS) clusters and cases of deaths by neoplasia in the Belo Horizonte municipality, Minas Gerais state, Brazil, from 1996 to 2006 and to measure the human exposure levels to EMF where there is a major concentration of cellular telephone transmitter antennas. A descriptive spatial analysis of the BSs and the cases of death by neoplasia identified in the municipality was performed through an ecological-epidemiological approach, using georeferencing. The database employed in the survey was composed of three data banks: 1. death by neoplasia documented by the Health Municipal Department; 2. BSs documented in ANATEL ('Agencia Nacional de Telecomunicacoes': 'Telecommunications National Agency'); and 3. census and demographic city population data obtained from official archives provided by IBGE ('Instituto Brasileiro de Geografia e Estatistica': 'Brazilian Institute of Geography and Statistics'). The results show that approximately 856 BSs were installed through December 2006. Most (39.60%) of the BSs were located in the 'Centro-Sul' ('Central-Southern') region of the municipality. Between 1996 and 2006, 7191 deaths by neoplasia occurred and within an area of 500 m from the BS, the mortality rate was 34.76 per 10,000 inhabitants. Outside of this area, a decrease in the number of deaths by neoplasia occurred. The greatest accumulated incidence was 5.83 per 1000 in the Central-Southern region and the lowest incidence was 2.05 per 1000 in the Barreiro region. During the environmental monitoring, the largest accumulated electric field measured was 12.4 V/m and the smallest was 0.4 V/m. The largest density power was 40.78 {mu

  17. Mortality by neoplasia and cellular telephone base stations in the Belo Horizonte municipality, Minas Gerais state, Brazil

    International Nuclear Information System (INIS)

    Pollution caused by the electromagnetic fields (EMFs) of radio frequencies (RF) generated by the telecommunication system is one of the greatest environmental problems of the twentieth century. The purpose of this research was to verify the existence of a spatial correlation between base station (BS) clusters and cases of deaths by neoplasia in the Belo Horizonte municipality, Minas Gerais state, Brazil, from 1996 to 2006 and to measure the human exposure levels to EMF where there is a major concentration of cellular telephone transmitter antennas. A descriptive spatial analysis of the BSs and the cases of death by neoplasia identified in the municipality was performed through an ecological-epidemiological approach, using georeferencing. The database employed in the survey was composed of three data banks: 1. death by neoplasia documented by the Health Municipal Department; 2. BSs documented in ANATEL ('Agencia Nacional de Telecomunicacoes': 'Telecommunications National Agency'); and 3. census and demographic city population data obtained from official archives provided by IBGE ('Instituto Brasileiro de Geografia e Estatistica': 'Brazilian Institute of Geography and Statistics'). The results show that approximately 856 BSs were installed through December 2006. Most (39.60%) of the BSs were located in the 'Centro-Sul' ('Central-Southern') region of the municipality. Between 1996 and 2006, 7191 deaths by neoplasia occurred and within an area of 500 m from the BS, the mortality rate was 34.76 per 10,000 inhabitants. Outside of this area, a decrease in the number of deaths by neoplasia occurred. The greatest accumulated incidence was 5.83 per 1000 in the Central-Southern region and the lowest incidence was 2.05 per 1000 in the Barreiro region. During the environmental monitoring, the largest accumulated electric field measured was 12.4 V/m and the smallest was 0.4 V/m. The largest density power was 40.78 μW/cm2, and the smallest was 0.04 μW/cm2. - Highlights:

  18. Evaluation of areal precipitation estimates based on downscaled reanalysis and station data by hydrological modelling

    Directory of Open Access Journals (Sweden)

    D. Duethmann

    2013-07-01

    Full Text Available In data sparse mountainous regions it is difficult to derive areal precipitation estimates. In addition, their evaluation by cross validation can be misleading if the precipitation gauges are not in representative locations in the catchment. This study aims at the evaluation of precipitation estimates in data sparse mountainous catchments. In particular, it is first tested whether monthly precipitation fields from downscaled reanalysis data can be used for interpolating gauge observations. Secondly, precipitation estimates from this and other methods are evaluated by comparing simulated and observed discharge, which has the advantage that the data are evaluated at the catchment scale. This approach is extended here in order to differentiate between errors in the overall bias and the temporal dynamics, and by taking into account different sources of uncertainties. The study area includes six headwater catchments of the Karadarya Basin in Central Asia. Generally the precipitation estimate based on monthly precipitation fields from downscaled reanalysis data showed an acceptable performance, comparable to another interpolation method using monthly precipitation fields from multi-linear regression against topographical variables. Poor performance was observed in only one catchment, probably due to mountain ridges not resolved in the model orography of the regional climate model. Using two performance criteria for the evaluation by hydrological modelling allowed a more informed differentiation between the precipitation data and showed that the precipitation data sets mostly differed in their overall bias, while the performance with respect to the temporal dynamics was similar. Our precipitation estimates in these catchments are considerably higher than those from continental- or global-scale gridded data sets. The study demonstrates large uncertainties in areal precipitation estimates in these data sparse mountainous catchments. In such regions with

  19. A Measurement Method of Time Jitter of a Laser Pulse with Respect to the Radio-Frequency Wave Phase in a Photocathode Radio-Frequency Gun

    Institute of Scientific and Technical Information of China (English)

    刘圣广; 李永贵; 王鸣凯

    2002-01-01

    In a photo-cathode radio-frequency (rf) gun, the micro-bunched charge output from the gun is dependent linearly on the laser injection phase, due to the Scottay effect in the process of photoemission and the procedure of the electron longitudinal acceleration. Based on this principle, a new method is proposed, which should be utilized to measure the time jitter between the driving laser pulse and the rf phase with a very high resolution of a few tens of femtoseconds.

  20. A portable air-quality station based on thick film gas sensors for real time detection of traces of atmospheric pollutants

    Science.gov (United States)

    Fioravanti, A.; Bonanno, A.; Gherardi, S.; Carotta, M. C.; Skouloudis, A. N.

    2016-03-01

    Different functional materials, single or mixed nano-crystalline semiconductor oxides, were synthesized via appropriated wet-chemistry routes. The powders were used to fabricate metal oxide (MOX) thick film gas sensors. Portable monitoring stations based on the aforementioned sensors were prepared, including electronics for acquisition, processing and wireless transmission of the data. Results of long term trials in field, carried out locating few units closely to as many conventional fixed-site monitoring stations, have been reported. The comparison was performed between the temporal evolution of the conductivity changes of the sensors with the pollutants’ concentrations, as measured by the analytical instruments.

  1. Mobile phone base stations and adverse health effects: phase 2 of a cross-sectional study with measured radio frequency electromagnetic fields

    DEFF Research Database (Denmark)

    Berg-Beckhoff, Gabriele; Blettner, M; Kowall, B;

    2009-01-01

    OBJECTIVE: The aim of the cross-sectional study was to test the hypothesis that exposure to continuous low-level radio frequency electromagnetic fields (RF-EMFs) emitted from mobile phone base stations was related to various health disturbances. METHODS: For the investigation people living mainly...... stations affected their health and they gave information on sleep disturbances, headaches, health complaints and mental and physical health using standardised health questionnaires. Information on stress was also collected. Multiple linear regression models were used with health outcomes as dependent...

  2. Swarm Intelligence-Based Smart Energy Allocation Strategy for Charging Stations of Plug-In Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Imran Rahman

    2015-01-01

    Full Text Available Recent researches towards the use of green technologies to reduce pollution and higher penetration of renewable energy sources in the transportation sector have been gaining popularity. In this wake, extensive participation of plug-in hybrid electric vehicles (PHEVs requires adequate charging allocation strategy using a combination of smart grid systems and smart charging infrastructures. Daytime charging stations will be needed for daily usage of PHEVs due to the limited all-electric range. Intelligent energy management is an important issue which has already drawn much attention of researchers. Most of these works require formulation of mathematical models with extensive use of computational intelligence-based optimization techniques to solve many technical problems. In this paper, gravitational search algorithm (GSA has been applied and compared with another member of swarm family, particle swarm optimization (PSO, considering constraints such as energy price, remaining battery capacity, and remaining charging time. Simulation results obtained for maximizing the highly nonlinear objective function evaluate the performance of both techniques in terms of best fitness.

  3. Reduced growth of soybean seedlings after exposure to weak microwave radiation from GSM 900 mobile phone and base station.

    Science.gov (United States)

    Halgamuge, Malka N; Yak, See Kye; Eberhardt, Jacob L

    2015-02-01

    The aim of this work was to study possible effects of environmental radiation pollution on plants. The association between cellular telephone (short duration, higher amplitude) and base station (long duration, very low amplitude) radiation exposure and the growth rate of soybean (Glycine max) seedlings was investigated. Soybean seedlings, pre-grown for 4 days, were exposed in a gigahertz transverse electromagnetic cell for 2 h to global system for mobile communication (GSM) mobile phone pulsed radiation or continuous wave (CW) radiation at 900 MHz with amplitudes of 5.7 and 41 V m(-1) , and outgrowth was studied one week after exposure. The exposure to higher amplitude (41 V m(-1)) GSM radiation resulted in diminished outgrowth of the epicotyl. The exposure to lower amplitude (5.7 V m(-1)) GSM radiation did not influence outgrowth of epicotyl, hypocotyls, or roots. The exposure to higher amplitude CW radiation resulted in reduced outgrowth of the roots whereas lower CW exposure resulted in a reduced outgrowth of the hypocotyl. Soybean seedlings were also exposed for 5 days to an extremely low level of radiation (GSM 900 MHz, 0.56 V m(-1)) and outgrowth was studied 2 days later. Growth of epicotyl and hypocotyl was found to be reduced, whereas the outgrowth of roots was stimulated. Our findings indicate that the observed effects were significantly dependent on field strength as well as amplitude modulation of the applied field. PMID:25644316

  4. Optimal Scheduling of Energy Storage System for Self-Sustainable Base Station Operation Considering Battery Wear-Out Cost

    Directory of Open Access Journals (Sweden)

    Yohwan Choi

    2016-06-01

    Full Text Available A self-sustainable base station (BS where renewable resources and energy storage system (ESS are interoperably utilized as power sources is a promising approach to save energy and operational cost in communication networks. However, high battery price and low utilization of ESS intended for uninterruptible power supply (UPS necessitates active utilization of ESS. This paper proposes a multi-functional framework of ESS using dynamic programming (DP for realizing a sustainable BS. We develop an optimal charging and discharging scheduling algorithm considering a detailed battery wear-out model to minimize operational cost as well as to prolong battery lifetime. Our approach significantly reduces total cost compared to the conventional method that does not consider battery wear-out. Extensive experiments for several scenarios exhibit that total cost is reduced by up to 70.6% while battery wear-out is also reduced by 53.6%. The virtue of the proposed framework is its wide applicability beyond sustainable BS and thus can be also used for other types of load in principle.

  5. A Regression Analysis for Base Station Power Consumption under Real Traffic Loads – A Case of Nepal

    Directory of Open Access Journals (Sweden)

    Madhu Sudan Dahal

    2015-12-01

    Full Text Available With the advent and rapid development of mobile and wireless technology, the field of Information and Communication Technology (ICT has become so lucrative and expanding at an alarming rate. Correspondingly energy consumption is also growing at a staggering rate. With this note, mobile operators are already among the top energy consumer. As the mass deployment of 3G systems in developing countries and later 4G systems rolling out worldwide, mobile communication consume significant amount of energy with large electricity bills. More than 50% of the total energy is consumed by the radio access part, whereas 50-80% is used for the power amplifier. This paper critically analyses the power consumption of Base Stations (BSs as per the traffic generated at various urban-dense location of Kathmandu, Nepal. It deals with real time traffic data on full load in per hour basis of ten BSs for consecutive ten days. The results revealed a linear relationship between the power consumption and traffic loads. As of findings, this paper vow an urgency to pursue an optimal capacity while designing wireless networks and also suggests an imperative pathways for energy efficient wireless communication.

  6. Tests of a new CCD-camera based neutron radiography detector system at the reactor stations in Munich and Vienna

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, E.; Pleinert, H. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Schillinger, B. [Technische Univ. Muenchen (Germany); Koerner, S. [Atominstitut der Oesterreichischen Universitaeten, Vienna (Austria)

    1997-09-01

    The performance of the new neutron radiography detector designed at PSI with a cooled high sensitive CCD-camera was investigated under real neutronic conditions at three beam ports of two reactor stations. Different converter screens were applied for which the sensitivity and the modulation transfer function (MTF) could be obtained. The results are very encouraging concerning the utilization of this detector system as standard tool at the radiography stations at the spallation source SINQ. (author) 3 figs., 5 refs.

  7. A Geometrical-based Vertical Gain Correction for Signal Strength Prediction of Downtilted Base Station Antennas in Urban Areas

    DEFF Research Database (Denmark)

    Rodriguez, Ignacio; Nguyen, Huan Cong; Sørensen, Troels Bundgaard;

    2012-01-01

    , with electrical antenna downtilt in the range from 0 to 10 degrees, as well as predictions based on ray-tracing and 3D building databases covering the measurement area. Although the calibrated ray-tracing predictions are highly accurate compared with the measured data, the combined LOS/NLOS COST...

  8. Flexible small size radiofrequency plasma torch for Tokamak wall cleaning

    International Nuclear Information System (INIS)

    Tritium accumulation in walls is a limiting factor in efficient long term operation of fusion machines. A number of detritiation techniques are under study, like laser, discharge, flash lamp based cleaning. One of the encountered difficulties is the limited access of the detritiation tool in narrow spaces, as in divertor region, inter-tiles or inside castellated gaps, where in fact an enhanced co-deposition and tritium trapping were observed. This contribution addresses the problem of elaboration of plasma torch as a tool appropriate for stimulating detritiation and removal of co-deposited layers in such spaces. The requirements imposed to the plasma torch source were related to the compatibility with inside torus operation: small diameter in order to permit access in narrow spaces, reasonable power, large range of working pressures from vacuum to atmosphere, closed loop cooling, flexibility in order to allow scanning and mounting on a robotic arm. The approached design is based on a radiofrequency discharge constricted to burn in a closed space between an active radiofrequency electrode and a grounded nozzle, from where plasma expands outside as a directional beam. The found solutions have led to a flexible hand held source working stable up to 300 W injected power and consisting of a cylindrical body of 20 mm diameter including the external water jacket embracing the discharge and an inside cooling circuit. The electrical characterization of the radiofrequency discharge sustaining the expanded plasma was performed and the domain of stable source operation in terms of power, current, pressure, argon mass flow rate is presented and discussed. The plasma beam size presents a strong dependence on pressure: the plasma length decreases from 200 mm to 20 mm, when pressure increases from vacuum to atmospheric, depending on power and mass flow rate. The ionized gas temperature, as indicated by a thermocouple head inserted in expansion in the nozzle proximity fall in the

  9. Model based multivariable controller for large scale compression stations. Design and experimental validation on the LHC 18KW cryorefrigerator

    Energy Technology Data Exchange (ETDEWEB)

    Bonne, François; Bonnay, Patrick [INAC, SBT, UMR-E 9004 CEA/UJF-Grenoble, 17 rue des Martyrs, 38054 Grenoble (France); Alamir, Mazen [Gipsa-Lab, Control Systems Department, CNRS-University of Grenoble, 11, rue des Mathématiques, BP 46, 38402 Saint Martin d' Hères (France); Bradu, Benjamin [CERN, CH-1211 Genève 23 (Switzerland)

    2014-01-29

    In this paper, a multivariable model-based non-linear controller for Warm Compression Stations (WCS) is proposed. The strategy is to replace all the PID loops controlling the WCS with an optimally designed model-based multivariable loop. This new strategy leads to high stability and fast disturbance rejection such as those induced by a turbine or a compressor stop, a key-aspect in the case of large scale cryogenic refrigeration. The proposed control scheme can be used to have precise control of every pressure in normal operation or to stabilize and control the cryoplant under high variation of thermal loads (such as a pulsed heat load expected to take place in future fusion reactors such as those expected in the cryogenic cooling systems of the International Thermonuclear Experimental Reactor ITER or the Japan Torus-60 Super Advanced fusion experiment JT-60SA). The paper details how to set the WCS model up to synthesize the Linear Quadratic Optimal feedback gain and how to use it. After preliminary tuning at CEA-Grenoble on the 400W@1.8K helium test facility, the controller has been implemented on a Schneider PLC and fully tested first on the CERN's real-time simulator. Then, it was experimentally validated on a real CERN cryoplant. The efficiency of the solution is experimentally assessed using a reasonable operating scenario of start and stop of compressors and cryogenic turbines. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO.

  10. Model based multivariable controller for large scale compression stations. Design and experimental validation on the LHC 18KW cryorefrigerator

    International Nuclear Information System (INIS)

    In this paper, a multivariable model-based non-linear controller for Warm Compression Stations (WCS) is proposed. The strategy is to replace all the PID loops controlling the WCS with an optimally designed model-based multivariable loop. This new strategy leads to high stability and fast disturbance rejection such as those induced by a turbine or a compressor stop, a key-aspect in the case of large scale cryogenic refrigeration. The proposed control scheme can be used to have precise control of every pressure in normal operation or to stabilize and control the cryoplant under high variation of thermal loads (such as a pulsed heat load expected to take place in future fusion reactors such as those expected in the cryogenic cooling systems of the International Thermonuclear Experimental Reactor ITER or the Japan Torus-60 Super Advanced fusion experiment JT-60SA). The paper details how to set the WCS model up to synthesize the Linear Quadratic Optimal feedback gain and how to use it. After preliminary tuning at CEA-Grenoble on the 400W@1.8K helium test facility, the controller has been implemented on a Schneider PLC and fully tested first on the CERN's real-time simulator. Then, it was experimentally validated on a real CERN cryoplant. The efficiency of the solution is experimentally assessed using a reasonable operating scenario of start and stop of compressors and cryogenic turbines. This work is partially supported through the European Fusion Development Agreement (EFDA) Goal Oriented Training Program, task agreement WP10-GOT-GIRO

  11. CT-guided radiofrequency tumor ablation in children

    Energy Technology Data Exchange (ETDEWEB)

    Botsa, Evanthia [National and Kapodistrian University of Athens, First Pediatric Clinic, Agia Sofia Children' s Hospital, Athens (Greece); Poulou, Loukia S.; Koundouraki, Antonia; Thanos, Loukas [Sotiria General Hospital for Chest Diseases, Department of Medical Imaging and Interventional Radiology, Athens (Greece); Koutsogiannis, Ioannis [General Military Hospital NIMTS, Department of Medical Imaging, Athens (Greece); Ziakas, Panayiotis D. [Warren Alpert Medical School of Brown University Rhode Island Hospital, Division of Infectious Diseases, Providence, RI (United States); Alexopoulou, Efthimia [Attikon University Hospital, Second Department of Radiology, Athens University School of Medicine, Athens (Greece)

    2014-11-15

    Image-guided radiofrequency ablation is a well-accepted technique of interventional oncology in adults. To evaluate the efficacy and safety of CT-guided radiofrequency ablation as a minimally invasive treatment for metastatic neoplasms in children. A total of 15 radiofrequency ablation sessions were performed in 12 children and young adults (median age 9.5; range 5-18 years) with metastatic malignancies. Seven children and young adults had secondary hepatic lesions, three had pulmonary and two had bone lesions. Radiofrequency ablation was performed under conscious sedation. The median lesion size was 1.7 cm (range 1.3-2.8 cm). The median time for ablation was 8 min (range 7-10 min). Radiofrequency procedures were technically successful in all tumors. Postablation imaging immediately after, and 1 month and 3 months after radiofrequency ablation showed total necrosis in all patients. At 6-month follow-up, three patients (all with lesion size >2 cm) had local recurrence and underwent a second radiofrequency ablation session. At 2-year follow-up no patient had recurrence of the treated tumor. Post-ablation syndrome occurred in four children. No major complication occurred. CT-guided radiofrequency tumor ablation was safe and efficient for palliative treatment in our cohort of patients. (orig.)

  12. Development of a new seismic-data acquisition station based on system-on-a-programmable-chip technology

    Directory of Open Access Journals (Sweden)

    Zhang Qi-sheng

    2013-08-01

    Full Text Available There has been considerable development of seismic detectors over the last 80 years. However, there is still a need to further develop new earthquake exploration and data acquisition systems with high precision. In particular, for China to keep up with the latest technology of these systems, it is important to be involved in the research and development, instead of importing systems that soon fall behind the latest technology. In this study, the features of system-on-a-programmable-chip (SoPC technology are analyzed and used to design a new digital seismic-data acquisition station. The hardware circuit of the station was developed, and the analog board and the main control data-transmission board were designed according to the needs of digital seismic-data acquisition stations. High-definition analog-to-digital converter sequential digital filter technology of the station (cascade integrator comb filter, finite impulse response digital filter were incorporated to provide advantages to the acquisition station, such as high definition, large dynamic scope, and low noise. A specific data-transmission protocol was designed for the station, which ensured a transmission speed of 16 Mbps along a 55-m wire with low power consumption. Synchronic acquisition was researched and developed, so as to achieve accuracy better than 200 ns. The key technologies were integrated into the SoPC of the main control data-transmission board, so as to ensure high-resolution acquisition of the station, while improving the accuracy of the synchronic acquisition and data-transmission speed, lowering the power consumption, and preparing for the follow-up efforts to tape out.

  13. EMS Stations, Emergency Medical Service Stations; EMS08; The EMS stations dataset consists of any location where emergency medical services (EMS) personnel are stationed or based out of, or where equipment that such personnel use in carrying out their jobs is stored, Published in 2010, 1:24000 (1in=2000ft) scale, State of Rhode Island and Providence Plantations.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This EMS Stations dataset, published at 1:24000 (1in=2000ft) scale, was produced all or in part from Other information as of 2010. It is described as 'Emergency...

  14. Long and short-term atmospheric radiation analyses based on coupled measurements at high altitude remote stations and extensive air shower modeling

    Science.gov (United States)

    Hubert, G.; Federico, C. A.; Pazianotto, M. T.; Gonzales, O. L.

    2016-02-01

    In this paper are described the ACROPOL and OPD high-altitude stations devoted to characterize the atmospheric radiation fields. The ACROPOL platform, located at the summit of the Pic du Midi in the French Pyrenees at 2885 m above sea level, exploits since May 2011 some scientific equipment, including a BSS neutron spectrometer, detectors based on semiconductor and scintillators. In the framework of a IEAv and ONERA collaboration, a second neutron spectrometer was simultaneously exploited since February 2015 at the summit of the Pico dos Dias in Brazil at 1864 m above the sea level. The both high station platforms allow for investigating the long period dynamics to analyze the spectral variation of cosmic-ray- induced neutron and effects of local and seasonal changes, but also the short term dynamics during solar flare events. This paper presents long and short-term analyses, including measurement and modeling investigations considering the both high altitude stations data. The modeling approach, based on ATMORAD computational platform, was used to link the both station measurements.

  15. A novel static frequency converter based on multilevel cascaded H-bridge used for the startup of synchronous motor in pumped-storage power station

    International Nuclear Information System (INIS)

    Research highlights: → A novel Static Frequency Converter (SFC) based on multilevel cascaded H-bridge (CHB) topology is proposed and used for the reversible pump-generating units in pumped-storage power station. → The novel SFC based on CHB has compact configuration, low current harmonic distortion and fast speed response. → Rotor position and Grid connection are realized successfully by the novel SFC. -- Abstract: A novel static frequency converter (SFC) is proposed and is used firstly to start the reversible pump-generating units in pumped-storage power station. Multilevel cascaded H-bridge (CHB) topology and Insulated Gate Bipolar Transistor (IGBT) are applied in the novel SFC. In comparison with the conventional SFC adopting load-commutated inverter (LCI) which is composed of silicon-controlled rectifier (SCR), the novel one has plenty of advantages such as compact configuration, low current harmonic distortion and fast speed response, and these advantages have been verified during 2-year operation at Xiang Hong Dian Pumped-storage power station in China. This application shows that the novel SFC greatly enhances the reliability and success rate of connecting to grid for starting up the pump-generating units. The principle, characteristic and performance of the novel SFC are described in this paper, and some key issues related to the startup of the units of the pumped-storage power station are also presented.

  16. Output improvement of Sg. Piah run-off river hydro-electric station with a new computed river flow-based control system

    International Nuclear Information System (INIS)

    The lower Sg. Piah hydro-electric station is a river run-off hydro scheme with generators capable of generating 55MW of electricity. It is located 30km away from Sg. Siput, a small town in the state of Perak, Malaysia. The station has two turbines (Pelton) to harness energy from water that flow through a 7km tunnel from a small intake dam. The trait of a run-off river hydro station is small-reservoir that cannot store water for a long duration; therefore potential energy carried by the spillage will be wasted if the dam level is not appropriately regulated. To improve the station annual energy output, a new controller based on the computed river flow has been installed. The controller regulates the dam level with an algorithm based on the river flow derived indirectly from the intake-dam water level and other plant parameters. The controller has been able to maintain the dam at optimum water level and regulate the turbines to maximize the total generation output.

  17. Output improvement of Sg. Piah run-off river hydro-electric station with a new computed river flow-based control system

    Science.gov (United States)

    Jidin, Razali; Othman, Bahari

    2013-06-01

    The lower Sg. Piah hydro-electric station is a river run-off hydro scheme with generators capable of generating 55MW of electricity. It is located 30km away from Sg. Siput, a small town in the state of Perak, Malaysia. The station has two turbines (Pelton) to harness energy from water that flow through a 7km tunnel from a small intake dam. The trait of a run-off river hydro station is small-reservoir that cannot store water for a long duration; therefore potential energy carried by the spillage will be wasted if the dam level is not appropriately regulated. To improve the station annual energy output, a new controller based on the computed river flow has been installed. The controller regulates the dam level with an algorithm based on the river flow derived indirectly from the intake-dam water level and other plant parameters. The controller has been able to maintain the dam at optimum water level and regulate the turbines to maximize the total generation output.

  18. How I do it: Radiofrequency ablation

    International Nuclear Information System (INIS)

    Over the past decade, image-guided tumor ablation using thermal energy has emerged as a promising technique for treating focal, primary or secondary, nonoperable tumors. Radiofrequency ablation (RFA) is minimally invasive and requires less resources, time, and recovery period and is, moreover, relatively inexpensive. RFA has been used to treat tumors located in the liver, lung, bone, kidneys, brain, thyroid, breast, and pancreas. This article will describe how to choose an appropriate case; precisely place the needle into the tumor; the precautions to be taken before, during, and after the procedure; probable complications; and the follow-up of patients undergoing ablation

  19. The cost-effectiveness of radiofrequency catheter ablation as first-line treatment for paroxysmal atrial fibrillation : results from a MANTRA-PAF substudy.

    OpenAIRE

    Aronsson, Mattias; Walfridsson, Håkan; Janzon, Magnus; Walfridsson, Ulla; Nielsen, Jens Cosedis; Hansen, Peter Steen; Johannessen, Arne; Raatikainen, Pekka; Hindricks, Gerhard; Kongstad, Ole; Pehrson, Steen; Englund, Anders; Hartikainen, Juha; Mortensen, Leif Spange; Levin, Lars-Åke

    2015-01-01

    AIM: The aim of this prospective substudy was to estimate the cost-effectiveness of treating paroxysmal atrial fibrillation (AF) with radiofrequency catheter ablation (RFA) compared with antiarrhythmic drugs (AADs) as first-line treatment. METHODS AND RESULTS: A decision-analytic Markov model, based on MANTRA-PAF (Medical Antiarrhythmic Treatment or Radiofrequency Ablation in Paroxysmal Atrial Fibrillation) study data, was developed to study long-term effects and costs of RFA compared with AA...

  20. Radiofrequency energy exposure from the Trilliant smart meter.

    Science.gov (United States)

    Foster, Kenneth R; Tell, Richard A

    2013-08-01

    This paper reviews radiofrequency (RF) field levels produced by electric utility meters equipped with RF transceivers (so-called Smart Meters), focusing on meters from one manufacturer (Trilliant, Redwood City, CA, USA, and Granby, QC, Canada). The RF transmission levels are summarized based on publicly available data submitted to the U.S. Federal Communications Commission supplemented by limited independent measurements. As with other Smart Meters, this meter incorporates a low powered radiofrequency transceiver used for a neighborhood mesh network, in the present case using ZigBee-compliant physical and medium access layers, operating in the 2.45 GHz unlicensed band but with a proprietary network architecture. Simple calculations based on a free space propagation model indicate that peak RF field intensities are in the range of 10 mW m or less at a distance of more than 1-2 m from the meters. However, the duty cycle of transmission from the meters is very low (meter that were consistent with data reported by the vendor to the U.S. Federal Communications Commission. Limited measurements conducted in two houses with the meters were unable to clearly distinguish emissions from the meters from the considerable electromagnetic clutter in the same frequency range from other sources, including Wi-Fi routers and, when it was activated, a microwave oven. These preliminary measurements disclosed the difficulties that would be encountered in characterizing the RF exposures from these meters in homes in the face of background signals from other household devices in the same frequency range. An appendix provides an introduction to Smart Meter technology. The RF transmitters in wireless-equipped Smart Meters operate at similar power levels and in similar frequency ranges as many other digital communications devices in common use, and their exposure levels are very far below U.S. and international exposure limits. PMID:23799502

  1. Introduction to railway GSM- R base station lightning protection%浅谈铁路GSM-R基站防雷

    Institute of Scientific and Technical Information of China (English)

    刘慧琼

    2014-01-01

    如今,城市化进程日益加快,高速铁路发展受到世界瞩目。GSM- R通信系统作为客运专线采用的主要通信手段,其应用越来越为普及。但在实际应用中,出于对节约土地资源以及检修维护等方面的考虑,GSM- R基站频频受到雷击影响。如何可靠防雷,这一问题备受铁路建设者们的关注与重视。本文针对以上相关问题做了详细的分析与并提出了解决办法。%Nowadays, with the increasing speeding up of urbanization process, the development of the high speed railway attracts the world's attention. The GSM- R communication system as the main means of communication used in passenger dedicated line, its application is more and more popularity. But considering the issues of the land resources conservation and maintenance considerations In the practical application, the GSM - R base station has often been affected by a lightning strike. The problem that how to make the anti- lighting reliably is worthy of railway builders’attention and care. This article gives the detailed analysis and solutions to solve the above problems.

  2. The radio-frequency design of an iris-type coupler for the CPHS radio-frequency quadrupole

    Institute of Scientific and Technical Information of China (English)

    XIONG Zheng-Feng; ZHENG Shu-Xin; XING Qing-Zi; GUAN Xia-Ling

    2012-01-01

    The Compact Pulsed Hadron Source (CPHS) project is a university-based proton accelerator platform (13 MeV,16 kW,50 mA peak current,0.5 ms pulse width at 50 Hz) for multi-disciplinary neutron and proton applications.The CPHS linac consists of a 3 MeV radio frequency quadrupole (RFQ) linac and a 13 MeV drift tube linac (DTL).Both the RFQ and DTL share a 325 MHz,2.1 MW klystron source.A single iris-type radio-frequency (RF) coupler is used to feed 537 kW of RF power to the RFQ cavity.Threedimensional electromagnetic models of the ridge-loaded tapered waveguide (RLWG) and the coupler-cavity system are presented,and the design process and results of the RLWG and iris plate are described in detail.

  3. Ground based observations of Pc3-Pc5 geomagnetic pulsation power at Antarctic McMurdo station

    Directory of Open Access Journals (Sweden)

    C. G. Maclennan

    1998-06-01

    Full Text Available The two horizontal geomagnetic components and, measured by a fluxgate magnetometer at Antarctic McMurdo station (corrected geomagnetic coordinates 80.0° S, 327.5° E, are analyzed for the period May-June 1994; the spectral powers are calculated and integrated over three frequency intervals corresponding to the nominal ranges. The time dependence of those integrated powers and their correlations with northern auroral indices and solar wind speed are considered. The observations are compared with previous results reported from Terra Nova Bay station (located near McMurdo at the same corrected geomagnetic latitude during Antarctic summer intervals. The differences found between the two stations are discussed in terms of the seasonal dependence of geomagnetic field line configurations in the near cusp region.

  4. Radio-frequency scanning tunnelling microscopy.

    Science.gov (United States)

    Kemiktarak, U; Ndukum, T; Schwab, K C; Ekinci, K L

    2007-11-01

    The scanning tunnelling microscope (STM) relies on localized electron tunnelling between a sharp probe tip and a conducting sample to attain atomic-scale spatial resolution. In the 25-year period since its invention, the STM has helped uncover a wealth of phenomena in diverse physical systems--ranging from semiconductors to superconductors to atomic and molecular nanosystems. A severe limitation in scanning tunnelling microscopy is the low temporal resolution, originating from the diminished high-frequency response of the tunnel current readout circuitry. Here we overcome this limitation by measuring the reflection from a resonant inductor-capacitor circuit in which the tunnel junction is embedded, and demonstrate electronic bandwidths as high as 10 MHz. This approximately 100-fold bandwidth improvement on the state of the art translates into fast surface topography as well as delicate measurements in mesoscopic electronics and mechanics. Broadband noise measurements across the tunnel junction using this radio-frequency STM have allowed us to perform thermometry at the nanometre scale. Furthermore, we have detected high-frequency mechanical motion with a sensitivity approaching approximately 15 fm Hz(-1/2). This sensitivity is on par with the highest available from nanoscale optical and electrical displacement detection techniques, and the radio-frequency STM is expected to be capable of quantum-limited position measurements. PMID:17972882

  5. Neurohumoral indicators of efficacy radiofrequency cardiac denervation

    Science.gov (United States)

    Evtushenko, A. V.; Evtushenko, V. V.; Saushkina, Yu. V.; Lishmanov, Yu. B.; Pokushalov, E. A.; Sergeevichev, D. S.; Gusakova, A. M.; Suslova, T. E.; Dymbrylova, O. N.; Bykov, A. N.; Syryamkin, V. I.; Kistenev, Yu. V.; Anfinogenova, Ya. D.; Smyshlyaev, K. A.; Lotkov, A. I.; Kurlov, I. O.

    2015-11-01

    In this study, we compared pre- and postoperative parameters of the cardiac sympathetic innervation. The aim of the study was to examine the approaches to evaluating the quality of radiofrequency (RF)-induced cardiac denervation by using non-invasive and laboratory methods. The study included 32 people with long-lasting persistent atrial fibrillation (AF). The patients were divided into 2 groups according to the objectives of the study: group 1 (main) - 21 patients with mitral valve diseases, which simultaneously with radiofrequency ablation (RFA) AF carried out on the effects of the paraganglionic nervous plexuses by C. Pappone (2004) and N. Doll (2008) schemes. The second group (control) contained 11 patients with heart diseases in sinus rhythm (the RF denervation not been performed). All patients, who underwent surgical treatment, were received examination of cardiac sympathetic tone by using 123I-MIBG. All of them made blood analysis from ascending aorta and coronary sinus to determine the level of norepinephrine and its metabolites before and after cardiac denervation. Data of radionuclide examination are correlating with laboratory data.

  6. Neurohumoral indicators of efficacy radiofrequency cardiac denervation

    Energy Technology Data Exchange (ETDEWEB)

    Evtushenko, A. V., E-mail: ave@cardio-tomsk.ru; Evtushenko, V. V. [National Research Tomsk State University, Tomsk (Russian Federation); Federal State Budgetary Scientific Institution “Research Institute for Cardiology”, Tomsk (Russian Federation); Saushkina, Yu. V.; Gusakova, A. M.; Suslova, T. E.; Dymbrylova, O. N.; Smyshlyaev, K. A.; Kurlov, I. O. [Federal State Budgetary Scientific Institution “Research Institute for Cardiology”, Tomsk (Russian Federation); Lishmanov, Yu. B.; Anfinogenova, Ya. D. [National Research Tomsk Polytechnic University, Tomsk (Russian Federation); Federal State Budgetary Scientific Institution “Research Institute for Cardiology”, Tomsk (Russian Federation); Sergeevichev, D. S. [Academician E.N. Meshalkin State Research Institute of Circulation Pathology, Novosibirsk (Russian Federation); Bykov, A. N.; Syryamkin, V. I.; Kistenev, Yu. V. [National Research Tomsk State University, Tomsk (Russian Federation); Lotkov, A. I. [Institute of Strength Physics and Materials Science of the Siberian Branch of the RAS, Tomsk (Russian Federation); Pokushalov, E. A.

    2015-11-17

    In this study, we compared pre- and postoperative parameters of the cardiac sympathetic innervation. The aim of the study was to examine the approaches to evaluating the quality of radiofrequency (RF)-induced cardiac denervation by using non-invasive and laboratory methods. The study included 32 people with long-lasting persistent atrial fibrillation (AF). The patients were divided into 2 groups according to the objectives of the study: group 1 (main) - 21 patients with mitral valve diseases, which simultaneously with radiofrequency ablation (RFA) AF carried out on the effects of the paraganglionic nervous plexuses by C. Pappone (2004) and N. Doll (2008) schemes. The second group (control) contained 11 patients with heart diseases in sinus rhythm (the RF denervation not been performed). All patients, who underwent surgical treatment, were received examination of cardiac sympathetic tone by using {sup 123}I-MIBG. All of them made blood analysis from ascending aorta and coronary sinus to determine the level of norepinephrine and its metabolites before and after cardiac denervation. Data of radionuclide examination are correlating with laboratory data.

  7. Radiofrequency spark chambers and delay line resonators

    International Nuclear Information System (INIS)

    According to a suggestion of A. Kastler, a spark chamber was excited by an undamped radiofrequency pulse and tracks about 1 mm wide obtained; the result was interpreted by computation of the coefficients of electronic amplification and partial ambipolar diffusion. This work led us to the construction of a new fast triggering undamped wave-train generator of very high tension (patent taken out by the C.E.A. under the no.: EN 7 134 650 the 27.9.1971). Since this apparatus uses a resonant storage line, its design implied a precise knowledge of high impedance delay lines. The experimental radiofrequency spectra of the input impedance of opened or short-circuited lines were plotted completely and analysed by the circuits theory, new measuring methods were established, dispersion relations accurately checked and the equivalence of the formulas, within the third order, with theses of Debye's Dipolar Absorption demonstrated. General properties of Hilbert's transform were also investigated. From the experimental point of view, the electromagnetic energy storage process was extended to the case of a liquid nitrogen-immersed resonant delay line. The good behavior of the cryogenic experiment, where the main difficulty of icing was overcame by the construction of special electrodes, offers great promise for extrapolation to superconductivity. (author)

  8. Risk based methods for optimised operation of power stations - a pilot study; Riskbaserade metoder foer optimerad drift av kraftvaermeverk - en foerstudie

    Energy Technology Data Exchange (ETDEWEB)

    Gunnars, Jens; Gustavsson, Fredrik [Det Norske Veritas AB, Stockholm (Sweden)

    2002-03-01

    Methods for risk based planning and management of maintenance and operation of mechanical components in power stations have been studied. Risk based methods may be utilised for analysis of the risk level with reference to both safety and economy of the plant. The methods can be an important tool for planning and optimisation of the annual investment in different types of maintenance actions, with the purpose of improving long term profitability. The risk based planning can include: selection of components, inspection intervals, coverage, planning of time for replacement/repair of components, and selection of operation conditions. The first part of the report is a general survey and description of risk based methods for analyse of mechanical components. Some problems specific to power stations are discussed. Application of quantitative RBI is illustrated for the water system in steam boiler number 5 at Aabyverket. The possibilities to decrease inspection costs or increase availability also for power stations is obvious, and is expected to result in competitive advantages. The use and understanding of quantitative reliability methods are a necessary and essential part of any RBI assessment.

  9. HSIP Fire Stations in New Mexico

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — Fire Stations in New Mexico Any location where fire fighters are stationed or based out of, or where equipment that such personnel use in carrying out their jobs is...

  10. Effects of short-term W-CDMA mobile phone base station exposure on women with or without mobile phone related symptoms.

    Science.gov (United States)

    Furubayashi, Toshiaki; Ushiyama, Akira; Terao, Yasuo; Mizuno, Yoko; Shirasawa, Kei; Pongpaibool, Pornanong; Simba, Ally Y; Wake, Kanako; Nishikawa, Masami; Miyawaki, Kaori; Yasuda, Asako; Uchiyama, Mitsunori; Yamashita, Hitomi Kobayashi; Masuda, Hiroshi; Hirota, Shogo; Takahashi, Miyuki; Okano, Tomoko; Inomata-Terada, Satomi; Sokejima, Shigeru; Maruyama, Eiji; Watanabe, Soichi; Taki, Masao; Ohkubo, Chiyoji; Ugawa, Yoshikazu

    2009-02-01

    To investigate possible health effects of mobile phone use, we conducted a double-blind, cross-over provocation study to confirm whether subjects with mobile phone related symptoms (MPRS) are more susceptible than control subjects to the effect of electromagnetic fields (EMF) emitted from base stations. We sent questionnaires to 5,000 women and obtained 2,472 valid responses from possible candidates; from these, we recruited 11 subjects with MPRS and 43 controls. There were four EMF exposure conditions, each of which lasted 30 min: continuous, intermittent, and sham exposure with and without noise. Subjects were exposed to EMF of 2.14 GHz, 10 V/m (W-CDMA), in a shielded room to simulate whole-body exposure to EMF from base stations, although the exposure strength we used was higher than that commonly received from base stations. We measured several psychological and cognitive parameters pre- and post-exposure, and monitored autonomic functions. Subjects were asked to report on their perception of EMF and level of discomfort during the experiment. The MPRS group did not differ from the controls in their ability to detect exposure to EMF; nevertheless they consistently experienced more discomfort, regardless of whether or not they were actually exposed to EMF, and despite the lack of significant changes in their autonomic functions. Thus, the two groups did not differ in their responses to real or sham EMF exposure according to any psychological, cognitive or autonomic assessment. In conclusion, we found no evidence of any causal link between hypersensitivity symptoms and exposure to EMF from base stations. PMID:18780296

  11. Sistem Pendukung Keputusan Penentuan Lokasi Pembangunan Tower Base Transceiver Station (BST) Pada PT. XL Axiata Tbk-Medan Dengan Metode Analytic Hierarchy Process (AHP)

    OpenAIRE

    Indika, Mika

    2010-01-01

    Fierce competition that's happening right now in telecomunication needs to make the service providers attempt to meet the needs of the communication network customers. The problem often faced is the determination of the location to build a base transceiver station towers new potential signals from the tower so that it can reach the customer. To help solve the problem required a decision support system that has the ability to analyze the appropriate selection of candidate sites by using method...

  12. A New Approach for Adipose Tissue Treatment and Body Contouring Using Radiofrequency-Assisted Liposuction

    OpenAIRE

    Paul, Malcolm; Mulholland, Robert Stephen

    2009-01-01

    A new liposuction technology for adipocyte lipolysis and uniform three-dimensional tissue heating and contraction is presented. The technology is based on bipolar radiofrequency energy applied to the subcutaneous adipose tissue and subdermal skin surface. Preliminary clinical results, thermal monitoring, and histologic biopsies of the treated tissue demonstrate rapid preaspiration liquefaction of adipose tissue, coagulation of subcutaneous blood vessels, and uniform sustained heating of tissue.

  13. Sum-rule analysis of radio-frequency spectroscopy of ultracold Fermi gas

    OpenAIRE

    Leggett, AJ; Zhang, S.

    2008-01-01

    We carried out an analysis based on sum rules and determined the radio-frequency spectroscopy shift observed in Chin 's experiment. It is shown that such a shift can be interpreted as spin correlations peculiar to a BCS-type state. An analytical form for the shift is obtained which enables us to make quantitative comparisons with the experiment throughout the crossover. We also calculated the width of the resonance. An interesting consequence is noticed, which can possibly be tested by future...

  14. Local Ablative Strategies for Ductal Pancreatic Cancer (Radiofrequency Ablation, Irreversible Electroporation): A Review

    OpenAIRE

    Salvatore Paiella; Roberto Salvia; Marco Ramera; Roberto Girelli; Isabella Frigerio; Alessandro Giardino; Valentina Allegrini; Claudio Bassi

    2016-01-01

    Pancreatic ductal adenocarcinoma (PDAC) has still a dismal prognosis. Locally advanced pancreatic cancer (LAPC) accounts for the 40% of the new diagnoses. Current treatment options are based on chemo- and radiotherapy regimens. Local ablative techniques seem to be the future therapeutic option for stage-III patients with PDAC. Radiofrequency Ablation (RFA) and Irreversible Electroporation (IRE) are actually the most emerging local ablative techniques used on LAPC. Initial clinical studies on ...

  15. Real-time clock and orbit calculation of the GPS satellite constellation based on observation data of RTIGS-station network

    International Nuclear Information System (INIS)

    Due to the development of faster communication networks and improving computer technology beside postprocessing techniques real-time applications and services are more and more created and used in the eld of precise positioning and navigation using global navigation satellite systems (GNSS) like GPS. Data formats like RTCM (NTRIP) or RTIGS serve in this manner as basic tool to transmit real-time GNSS observation data to a eld of users. To handle this trend to real-time, the International GNSS Service (IGS) or more precisely the Real-Time Working Group (RTWG) of the IGS started to establish a global GNSS station network several years ago. These reference stations (RTIGS stations) transmit their observation data in real-time via the open internet to registerd users to support the development of potential new real-time products and services. One example for such a new real-time application based on the observations of the RTIGS network is the software RTIGU-Control developed within this PHD thesis. RTIGU-Control fulls 2 main tasks. The rst task is the monitoring (integrity) of the predicted IGS orbit and clock products (IGU products) using real-time observations from the station network. The second task deals with calculating more precise satellite and station clock corrections compared to the predicted values of the IGU solutions based on the already very precise IGU orbit solutions. In a rst step RTIGU-Control calculates based on the IGU orbit predictions together with code-smoothed station observations precise values for the satellite and station clock corrections.The code-smoothed observations are additionally corrected for several corrections eecting the GNSS observations (for example the delay of the signal propagation time due to the atmosphere, relativistic eects, etc.). The second calculation step deals with monitoring the IGU predicted orbits using the calculated clock solution in the calculation step before and again the corrected real-time observations

  16. Dusty Plasma Physics Facility for the International Space Station

    Science.gov (United States)

    Goree, John; Hahn, Inseob

    2015-09-01

    The Dusty Plasma Physics Facility (DPPF) is an instrument planned for the International Space Station (ISS). If approved by NASA, JPL will build and operate the facility, and NASA will issue calls for proposals allowing investigators outside JPL to carry out research, public education, and outreach. Microgravity conditions on the ISS will be useful for eliminating two unwanted effects of gravity: sedimentation of dust particles to the bottom of a plasma chamber, and masking weak forces such as the ion drag force that act on dust particles. The DPPF facility is expected to support multiple scientific users. It will have a modular design, with a scientific locker, or insert, that can be exchanged without removing the entire facility. The first insert will use a parallel-plate radio-frequency discharge, polymer microspheres, and high-speed video cameras. This first insert will be designed for fundamental physics experiments. Possible future inserts could be designed for other purposes, such as engineering applications, and experimental simulations of astrophysical or geophysical conditions. The design of the facility will allow remote operation from ground-based laboratories, using telescience.

  17. Semitransparent ZnO/poly(3,4-ethylenedioxythiophene) based hybrid inorganic/organic heterojunction thin film diodes prepared by combined radio-frequency magnetron-sputtering and electrodeposition techniques

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Moreno, Jorge; Navarrete-Astorga, Elena; Martin, Francisco [Laboratorio de Materiales y Superficies (Unidad Asociada al CSIC), Departamentos de Fisica Aplicada and Ing. Quimica, Universidad de Malaga, E29071 Malaga (Spain); Schrebler, Ricardo [Instituto de Quimica, Facultad de Ciencias, Pontificia Universidad Catolica de Valparaiso, Casilla 4059, Valparaiso (Chile); Ramos-Barrado, Jose R. [Laboratorio de Materiales y Superficies (Unidad Asociada al CSIC), Departamentos de Fisica Aplicada and Ing. Quimica, Universidad de Malaga, E29071 Malaga (Spain); Dalchiele, Enrique A., E-mail: dalchiel@fing.edu.uy [Instituto de Fisica, Facultad de Ingenieria, Herrera y Reissig 565, C.C. 30, 11000 Montevideo (Uruguay)

    2012-12-15

    n-ZnO/p-poly(3,4-ethylenedioxythiophene) (PEDOT) semitransparent inorganic-organic hybrid vertical heterojunction thin film diodes have been fabricated with PEDOT and ZnO thin films grown by electrodeposition and radio-frequency magnetron-sputtering respectively, onto a tin doped indium oxide coated glass substrate. The diode exhibited an optical transmission of {approx} 40% to {approx} 50% in the visible region between 450 and 700 nm. The current-voltage (I-V) characteristics of the heterojunction show good rectifying diode characteristics, with a ratio of forward current to the reverse current as high as 35 in the range - 4 V to + 4 V. The I-V characteristic was examined in the framework of the thermionic emission model. The ideality factor and barrier height were obtained as 4.0 and 0.88 eV respectively. - Highlights: Black-Right-Pointing-Pointer Semitransparent inorganic-organic heterojunction thin film diodes investigated Black-Right-Pointing-Pointer n-ZnO/p-poly(3,4-ethylenedioxythipohene) used for the heterojunction Black-Right-Pointing-Pointer Diodes exhibited an optical transmission of {approx} 40%-{approx} 50% in the visible region Black-Right-Pointing-Pointer Heterojunction current-voltage features show good rectifying diode characteristics Black-Right-Pointing-Pointer A forward to reverse current ratio as high as 35 (- 4 V to + 4 V range) was attained.

  18. Semitransparent ZnO/poly(3,4-ethylenedioxythiophene) based hybrid inorganic/organic heterojunction thin film diodes prepared by combined radio-frequency magnetron-sputtering and electrodeposition techniques

    International Nuclear Information System (INIS)

    n-ZnO/p-poly(3,4-ethylenedioxythiophene) (PEDOT) semitransparent inorganic–organic hybrid vertical heterojunction thin film diodes have been fabricated with PEDOT and ZnO thin films grown by electrodeposition and radio-frequency magnetron-sputtering respectively, onto a tin doped indium oxide coated glass substrate. The diode exhibited an optical transmission of ∼ 40% to ∼ 50% in the visible region between 450 and 700 nm. The current–voltage (I–V) characteristics of the heterojunction show good rectifying diode characteristics, with a ratio of forward current to the reverse current as high as 35 in the range − 4 V to + 4 V. The I–V characteristic was examined in the framework of the thermionic emission model. The ideality factor and barrier height were obtained as 4.0 and 0.88 eV respectively. - Highlights: ► Semitransparent inorganic–organic heterojunction thin film diodes investigated ► n-ZnO/p-poly(3,4-ethylenedioxythipohene) used for the heterojunction ► Diodes exhibited an optical transmission of ∼ 40%–∼ 50% in the visible region ► Heterojunction current–voltage features show good rectifying diode characteristics ► A forward to reverse current ratio as high as 35 (− 4 V to + 4 V range) was attained

  19. Nonsurgical Transurethral Radiofrequency Collagen Denaturation: Results at Three Years after Treatment

    Directory of Open Access Journals (Sweden)

    Denise M. Elser

    2011-01-01

    Full Text Available Objective. To assess treatment efficacy and quality of life in women with stress urinary incontinence 3 years after treatment with nonsurgical transurethral radiofrequency collagen denaturation. Methods. This prospective study included 139 women with stress urinary incontinence due to bladder outlet hypermobility. Radiofrequency collagen denaturation was performed using local anesthesia in an office setting. Assessments included incontinence quality of life (I-QOL and urogenital distress inventory (UDI-6 instruments. Results. In total, 139 women were enrolled and 136 women were treated (mean age, 47 years. At 36 months, intent-to-treat analysis (n=139 revealed significant improvements in quality of life. Mean I-QOL score improved 17 points from baseline (P=.0004, while mean UDI-6 score improved (decreased 19 points (P=.0005. Conclusions. Transurethral collagen denaturation is a low-risk, office-based procedure that results in durable quality-of-life improvements in a significant proportion of women for as long as 3 years.

  20. Unexplained liver laceration after metastasis radiofrequency ablation

    Institute of Scientific and Technical Information of China (English)

    Esther U(n)a; Javier Trueba; Jose Manuel Montes

    2009-01-01

    Many studies have established the role of radiofrequency (RF) ablation as a minimally invasive treatment for liver metastases. Although relatively safe, several complications have been reported with the increased use of RF ablation. We describe here a case of unexplained liver laceration after a RF procedure. A woman who presented a solitary metachronous liver metastasis underwent RF ablation treatment for this lesion. Six hours later the patient displayed fatigue and pallor.Emergency blood tests showed a haemoglobin level of < 7 g/dL and markedly elevated transaminase levels.A computed tomography examination revealed two areas of liver laceration with haematoma, one of them following the path of the needle and the other leading away from the first. Following a blood transfusion, the patient was haemodynamically stable and completely recovered 24 h later. The patient remained in bed for 1 wk. No surgical intervention was required, and she was discharged 1 wk later.

  1. Palliative Radiofrequency Ablation for Recurrent Prostate Cancer

    International Nuclear Information System (INIS)

    Percutaneous radiofrequency ablation (RFA) is a minimally invasive local therapy for cancer. Its efficacy is now becoming well documented in many different organs, including liver, kidney, and lung. The goal of RFA is typically complete eradication of a tumor in lieu of an invasive surgical procedure. However, RFA can also play an important role in the palliative care of cancer patients. Tumors which are surgically unresectable and incompatible for complete ablation present the opportunity for RFA to be used in a new paradigm. Cancer pain runs the gamut from minor discomfort relieved with mild pain medication to unrelenting suffering for the patient, poorly controlled by conventional means. RFA is a tool which can potentially palliate intractable cancer pain. We present here a case in which RFA provided pain relief in a patient with metastatic prostate cancer with pain uncontrolled by conventional methods

  2. LAPAROSCOPIC NEPHRECTOMY USING RADIOFREQUENCY THERMAL ABLATION

    Directory of Open Access Journals (Sweden)

    B. Ya. Alekseev

    2014-08-01

    Full Text Available The wide use of current diagnostic techniques, such as ultrasound study, computed tomography, and magnetic resonance imaging, has led to significantly increased detection rates for disease in its early stages. This gave rise to a change in the standards for the treatment of locally advanced renal cell carcinoma (RCC. Laparoscopic nephrectomy (LN has recently become the standard treatment of locally advanced RCC in the clinics having much experience with laparoscopic surgery. The chief drawback of LN is difficulties in maintaining intraoperative hemostasis and a need for creating renal tissue ischemia. The paper gives the intermediate results of application of the new procedure of LN using radiofrequency thermal ablation in patients with non-ischemic early-stage RCC.

  3. Radiofrequency encoded angular-resolved light scattering

    DEFF Research Database (Denmark)

    Buckley, Brandon W.; Akbari, Najva; Diebold, Eric D.;

    2015-01-01

    The sensitive, specific, and label-free classification of microscopic cells and organisms is one of the outstanding problems in biology. Today, instruments such as the flow cytometer use a combination of light scatter measurements at two distinct angles to infer the size and internal complexity...... of cells at rates of more than 10,000 per second. However, by examining the entire angular light scattering spectrum it is possible to classify cells with higher resolution and specificity. Current approaches to performing these angular spectrum measurements all have significant throughput limitations...... Encoded Angular-resolved Light Scattering (REALS), this technique multiplexes angular light scattering in the radiofrequency domain, such that a single photodetector captures the entire scattering spectrum from a particle over approximately 100 discrete incident angles on a single shot basis. As a proof...

  4. Radiofrequency thermal ablation of renal tumors.

    Science.gov (United States)

    De Filippo, Massimo; Bozzetti, Francesca; Martora, Rosa; Zagaria, Raffaella; Ferretti, Stefania; Macarini, Luca; Brunese, Luca; Rotondo, Antonio; Rossi, Cristina

    2014-07-01

    Percutaneous radiofrequency ablation (PRFA) of renal malignancies is currently a therapeutic option for patients who are not able to undergo surgery. Some authors consider PRFA as the therapeutic standard in the treatment of renal neoplasms in non-operable patients due to comorbid conditions and in patients with mild-moderate renal failure, to preserve residual renal functionality. The use of PRFA has become more and more widespread due to a rise in the incidental detection of renal cell carcinomas with the ever-increasing use of Imaging for the study of abdominal diseases. Clinical studies indicate that RF ablation is an effective therapy with a low level of risk of complications, which provides good results in selected patients over short and medium term periods of time, however up to now few long-term studies have been carried out which can confirm the effectiveness of PRFA. PMID:25024061

  5. Swarm Intelligence-Based Smart Energy Allocation Strategy for Charging Stations of Plug-In Hybrid Electric Vehicles

    OpenAIRE

    Imran Rahman; Pandian M. Vasant; Balbir Singh Mahinder Singh; Abdullah-Al-Wadud, M.

    2015-01-01

    Recent researches towards the use of green technologies to reduce pollution and higher penetration of renewable energy sources in the transportation sector have been gaining popularity. In this wake, extensive participation of plug-in hybrid electric vehicles (PHEVs) requires adequate charging allocation strategy using a combination of smart grid systems and smart charging infrastructures. Daytime charging stations will be needed for daily usage of PHEVs due to the limited all-electric range....

  6. Risk-informed profitability-based analysis support of nuclear power station balance-of-plant change management

    International Nuclear Information System (INIS)

    In this paper, a three-phased method is proposed for the STP Nuclear Operating Company (STPNOC) Risk and Reliability Analysis Section (RRA) to perform analyses and decision-making support for the STPNOC Balance-of-Plant (BOP)Task Force in managing change to simultaneously optimize plant safety and maximize long-term return-on-asset (or profitability) for the South Texas Project Electric Generating Station (STPEGS). (authors)

  7. CAD-based stand-alone spacecraft radiation exposure analysis system: An application of the early man-tended Space Station

    Science.gov (United States)

    Appleby, M. H.; Golightly, M. J.; Hardy, A. C.

    1993-01-01

    Major improvements have been completed in the approach to analyses and simulation of spacecraft radiation shielding and exposure. A computer-aided design (CAD)-based system has been developed for determining the amount of shielding provided by a spacecraft and simulating transmission of an incident radiation environment to any point within or external to the vehicle. Shielding analysis is performed using a customized ray-tracing subroutine contained within a standard engineering modeling software package. This improved shielding analysis technique has been used in several vehicle design programs such as a Mars transfer habitat, pressurized lunar rover, and the redesigned international Space Station. Results of analysis performed for the Space Station astronaut exposure assessment are provided to demonastrate the applicability and versatility of the system.

  8. Capacity Calculation of Shunt Active Power Filters for Electric Vehicle Charging Stations Based on Harmonic Parameter Estimation and Analytical Modeling

    Directory of Open Access Journals (Sweden)

    Niancheng Zhou

    2014-08-01

    Full Text Available The influence of electric vehicle charging stations on power grid harmonics is becoming increasingly significant as their presence continues to grow. This paper studies the operational principles of the charging current in the continuous and discontinuous modes for a three-phase uncontrolled rectification charger with a passive power factor correction link, which is affected by the charging power. A parameter estimation method is proposed for the equivalent circuit of the charger by using the measured characteristic AC (Alternating Current voltage and current data combined with the charging circuit constraints in the conduction process, and this method is verified using an experimental platform. The sensitivity of the current harmonics to the changes in the parameters is analyzed. An analytical harmonic model of the charging station is created by separating the chargers into groups by type. Then, the harmonic current amplification caused by the shunt active power filter is researched, and the analytical formula for the overload factor is derived to further correct the capacity of the shunt active power filter. Finally, this method is validated through a field test of a charging station.

  9. Positioning of ground-based Global Light System stations around the World for the JEM-EUSO mission

    Science.gov (United States)

    Norman, Zachary

    2013-04-01

    The astrophysical origins of the Extreme Energy Cosmic Rays (EECRs - E >10^20 eV) remain a matter of debate. Data obtained on EECRs is sparse, due to the very low flux reaching the Earth. The Extreme Universe Space Observatory on board the Japanese Experiment Module (JEM-EUSO) on the International Space Station (ISS) will measure the properties of EECRs by recording the UV light produced by the air showers in Earth's atmosphere from space. At these extremely high energies, there is no way to calibrate the detector and test its operation with man-made accelerators. However, it is possible to induce the detector to see a similar amount of light by using an array of Global Light System (GLS) stations, which will use xenon flashers and lasers. The GLS locations need to be representative of the different climates around the World, because the development of the air showers depends upon the general properties of the atmosphere where it occurs. In this context, a program was developed to predict when a given GLS station is able to fire test shots within the field of view of the JEM-EUSO detector as the ISS flies over. This program takes into account the trajectory of the ISS, the relative positions of the Sun and the Moon, as well as the average cloud cover over the candidate sites.

  10. Genetic effects of radiofrequency radiation (RFR)

    International Nuclear Information System (INIS)

    The possible effects of radiofrequency (RF) exposure on the genetic material of cells are considered very important since damage to the DNA of somatic cells can be linked to cancer development or cell death whereas damage to germ cells can lead to genetic damage in next and subsequent generations. This is why the scientific literature reports many investigations on the subject. According to a number of review papers, the conclusion so far is that there is little evidence that RFR is directly mutagenic and that adverse effects that were reported in some of the papers are predominantly the result of hyperthermia. Yet, some subtle indirect effects on DNA replication and/or transcription of genes under relatively restricted exposure conditions cannot be ruled out. Furthermore, the possibility of combined effects of RFR with environmental carcinogens/mutagens merits further attention. The present paper takes into account more recent investigations but the conclusion remains the same. A majority of studies report no increased (cyto)genetic damage but yet, a considerable number of investigations do. However, many studies were not sufficiently characterized, are therefore difficult to replicate and cannot be compared to others. Experimental protocols were very different from one study to another and investigations from a single laboratory were very often limited in the sample size or number of cells investigated, preventing a robust statistical analysis. Subtle, but significant differences between RFR-exposed and sham-exposed cells cannot be found in such conditions. For the above reasons, it was concluded at a workshop in Loewenstein (November 2002) that further investigations by individual laboratories most probably will not add much to the discussion of radiofrequency radiation (RFR) genotoxicity. Large, well coordinated, international collaborative studies involving participation of several experienced scientists are considered an alternative of uttermost importance

  11. The Optimization Based Dynamic and Cyclic Working Strategies for Rechargeable Wireless Sensor Networks with Multiple Base Stations and Wireless Energy Transfer Devices

    Directory of Open Access Journals (Sweden)

    Xu Ding

    2015-03-01

    Full Text Available In this paper, the optimal working schemes for wireless sensor networks with multiple base stations and wireless energy transfer devices are proposed. The wireless energy transfer devices also work as data gatherers while charging sensor nodes. The wireless sensor network is firstly divided into sub networks according to the concept of Voronoi diagram. Then, the entire energy replenishing procedure is split into the pre-normal and normal energy replenishing stages. With the objective of maximizing the sojourn time ratio of the wireless energy transfer device, a continuous time optimization problem for the normal energy replenishing cycle is formed according to constraints with which sensor nodes and wireless energy transfer devices should comply. Later on, the continuous time optimization problem is reshaped into a discrete multi-phased optimization problem, which yields the identical optimality. After linearizing it, we obtain a linear programming problem that can be solved efficiently. The working strategies of both sensor nodes and wireless energy transfer devices in the pre-normal replenishing stage are also discussed in this paper. The intensive simulations exhibit the dynamic and cyclic working schemes for the entire energy replenishing procedure. Additionally, a way of eliminating “bottleneck” sensor nodes is also developed in this paper.

  12. Interactions between radiofrequency signals and living organisms; Interactions entre signaux radiofrequences et vivants

    Energy Technology Data Exchange (ETDEWEB)

    Boudin, F.; Hours, M.; Lacronique, J.F.; Conil, E.; Hadjem, A.; El Habachi, A.; Wiart, K.; Mann, S.; Kundi, M.; Marc-Vergnes, J.P.; Roosli, M.; Mohler, E.; Frei, P.; Davis, Ch.C.; Balzano, Q.; Ait-Aissa, S.; Billaudel, B.; Poulletier De Gannes, F.; Hurtier, A.; Haro, E.; Taxile, M.; Veyret, B.; Lagroye, I.; Ait-Aissa, S.; Poulletier De Gannes, F.; Athane, A.; Veyret, B.; Lagroye, I.; Yardin, C.; Perrin, A.; Freire, M.; Bachelet, Ch.; Collin, A.; Pla, S.; Debouzy, J.C.; Leveque, Ph.; Van Nierop, L.E.; Huss, A.; Roosli, M.; Egger, M.; Calvez, M.; Salomon, D.

    2010-11-15

    This dossier is composed of 13 articles dealing with the interactions between radio-frequencies and living organisms. It is an overview of various scientific approaches to the field and is of interest for all citizens as the use of mobile phones is widely spread. In the first article it is shown how a model has been built to assess the distribution of the whole body exposure of the population. The second article reviews the state of the art in personal exposure measurements at radio-frequencies. The third article shows that the knowledge of the mechanism of action by which exposure increases the risk of health hazards is necessary. The fourth article shows that individual neuro-psychic factors take a prominent but maybe not unique, part in electromagnetic hypersensitivity. The fifth article shows that no evidence was found to link health disturbances of electromagnetic hypersensitive individuals with radiofrequency exposure. The sixth article shows that the wireless phone is not an athermal hazard to the brain. The seventh article shows that the in utero and post-natal exposure to Wi-Fi does not damage the brains of young rats. The eighth article concludes that recent studies provide no convincing proof of deleterious effects of radiofrequency exposure on the integrity of the blood-brain barrier for specific absorption rates up to 6 W/kg. The ninth article shows that no co-genotoxic effect of radiofrequency was found at levels of exposure that did not induce heating. The tenth article confirms that industry-sponsored studies were least likely to report results suggesting effects. The last article shows that general practitioners are increasingly questioned by their patients about the issue of electromagnetic waves. (A.C.) Available from doi:

  13. Pickering generating station

    International Nuclear Information System (INIS)

    The design, operation, and economics of the Pickering generating station are described. Pickering A comprises four 508MW(e) units and is based on the Candu system of heavy water moderated, pressurised heavy water cooled, uranium dioxide fueled, horizontal pressure tube reactor. Brief details are given of station layout and principle design parameters. Safety features are described and a brief account is given of scheduling, construction and commissioning. Operating performance is discussed. Turbine generators and auxiliaries, and the feedwater system contributed to more than half the outage time. An illustration is given of incorrect rolling operation which caused cracks in the Zr-Nb pressure tube, resulting in several leaks in Unit 3. Heavy water losses were low, as were radioactive releases. Economic features are discussed in terms of capital cost operating costs and total unit energy cost. Reference is made to Pickering B which is a 4 x 540MW(e) station, a mirror image of Pickering A, and scheduled for operation in 1980. The interest in the Pickering station being shown in many areas of the world is attributed to its simplicity, low fuel cycle cost, versatile pressure tube design features which meet requirements for safety, reliability, and maintainability. (U.K.)

  14. Interior Alaska Gravity Station Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The gravity station data total 9416 records. This data base was received in March 1997. Principal gravity parameters include Free-air Anomalies which have been...

  15. Gravity Station Data for Portugal

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The gravity station data total 3064 records. This data base was received in April 1997. Principal gravity parameters include Free-air Anomalies which have been...

  16. Gravity Station Data for Spain

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The gravity station data total 28493 records. This data base was received in April 1997. Principal gravity parameters include Free-air Anomalies which have been...

  17. Administrative norms on radiofrequency radiation for occupationally exposed persons

    International Nuclear Information System (INIS)

    The report presents a proposal for administrative norms on radiofrequency (RF) radiation for occupationally exposed persons. The norms establish maximum allowable field exposure in a frequency range from 1 MHz too 300 GHz. (RF)

  18. Imaging evaluation of liver cancer after radiofrequency ablation therapy

    International Nuclear Information System (INIS)

    Radiofrequency ablation has been an important means of the comprehensive therapy for liver cancers, especially for the treatment of small hepatocellular carcinomas. Radiofrequency ablation has already showed encouraging clinical effects. However, due to the limitation of ablation extent the remnants of tumor lesions or the recurrence of tumor are often seen. Therefore, it is very important to accurately evaluate the curative effect of radiofrequency ablation. This paper aims to summarize the evaluation of curative effect of radiofrequency ablation with different imaging methods, and to discuss the advantages and disadvantages of these different imaging methods in order to provide a correct reference for taking reasonable imaging means to help make the proper clinical treatment. (authors)

  19. An unshielded radio-frequency atomic magnetometer with sub-femtoTesla sensitivity

    International Nuclear Information System (INIS)

    We demonstrate a radio-frequency potassium-vapor magnetometer operating with sensitivities of 0.3 fT/√(Hz) at 0.5 MHz and 0.9 fT/√(Hz) at 1.31 MHz in the absence of radio-frequency and mu-metal or magnetic shielding. The use of spatially separated magnetometers, two voxels within the same cell, permits for the subtraction of common mode noise and the retention of a gradient signal, as from a local source. At 0.5 MHz the common mode noise was white and measured to be 3.4 fT/√(Hz); upon subtraction the noise returned to the values observed when the magnetometer was shielded. At 1.31 MHz, the common mode noise was from a nearby radio station and was reduced by a factor of 33 upon subtraction, limited only by the radio signal picked up by receiver electronics. Potential applications include in-the-field low-field magnetic resonance, such as the use of nuclear quadrupole resonance for the detection of explosives

  20. Thermal Protection with 5% Dextrose Solution Blanket During Radiofrequency Ablation

    OpenAIRE

    Chen, Enn Alexandria; Neeman, Ziv; Lee, Fred. T.; Kam, Anthony; Wood, Brad

    2006-01-01

    A serious complication for any thermal radiofrequency ablation is thermal injury to adjacent structures, particularly the bowel, which can result in additional major surgery or death. Several methods using air, gas, fluid, or thermometry to protect adjacent structures from thermal injury have been reported. In the cases presented in this report, 5% dextrose water (D5W) was instilled to prevent injury to the bowel and diaphragm during radiofrequency ablation. Creating an Insulating envelope or...