WorldWideScience

Sample records for solar radiation sensor

  1. Biological Sensors for Solar Ultraviolet Radiation

    Directory of Open Access Journals (Sweden)

    André P. Schuch

    2011-04-01

    Full Text Available Solar ultraviolet (UV radiation is widely known as a genotoxic environmental agent that affects Earth ecosystems and the human population. As a primary consequence of the stratospheric ozone layer depletion observed over the last decades, the increasing UV incidence levels have heightened the concern regarding deleterious consequences affecting both the biosphere and humans, thereby leading to an increase in scientific efforts to understand the role of sunlight in the induction of DNA damage, mutagenesis, and cell death. In fact, the various UV-wavelengths evoke characteristic biological impacts that greatly depend on light absorption of biomolecules, especially DNA, in living organisms, thereby justifying the increasing importance of developing biological sensors for monitoring the harmful impact of solar UV radiation under various environmental conditions. In this review, several types of biosensors proposed for laboratory and field application, that measure the biological effects of the UV component of sunlight, are described. Basically, the applicability of sensors based on DNA, bacteria or even mammalian cells are presented and compared. Data are also presented showing that on using DNA-based sensors, the various types of damage produced differ when this molecule is exposed in either an aqueous buffer or a dry solution. Apart from the data thus generated, the development of novel biosensors could help in evaluating the biological effects of sunlight on the environment. They also emerge as alternative tools for using live animals in the search for protective sunscreen products.

  2. Shield or not to Shield: Effects of Solar Radiation on Water Temperature Sensor Accuracy

    Directory of Open Access Journals (Sweden)

    Robert L. Wilby

    2013-10-01

    Full Text Available Temperature sensors are potentially susceptible to errors due to heating by solar radiation. Although this is well known for air temperature (Ta, significance to continuous water temperature (Tw monitoring is relatively untested. This paper assesses radiative errors by comparing measurements of exposed and shielded Tinytag sensors under indirect and direct solar radiation, and in laboratory experiments under controlled, artificial light. In shallow, still-water and under direct solar radiation, measurement discrepancies between exposed and shielded sensors averaged 0.4 °C but can reach 1.6 °C. Around 0.3 °C of this inconsistency is explained by variance in measurement accuracy between sensors; the remainder is attributed to solar radiation. Discrepancies were found to increase with light intensity, but to attain Tw differences in excess of 0.5 °C requires direct, bright solar radiation (>400 W m−2 in the total spectrum. Under laboratory conditions, radiative errors are an order of magnitude lower when thermistors are placed in flowing water (even at velocities as low as 0.1 m s−1. Radiative errors were also modest relative to the discrepancy between different thermistor manufacturers. Based on these controlled experiments, a set of guidelines are recommended for deploying thermistor arrays in water bodies.

  3. Performance Evaluation of Radiation Sensors for the Solar Energy Sector

    Directory of Open Access Journals (Sweden)

    Laurent Vuilleumier

    2017-11-01

    Full Text Available Rotating Shadowband Irradiometers (RSI and SPN1 Sunshine Pyranometers allow determining the diffuse and direct components of solar radiation without sun trackers; they can be deployed in networks for continuous field operation with modest maintenance. Their performances are evaluated here by analyzing their errors with respect to well characterized references. The analysis is based on 1‑minute data recorded over a 15‑month period at the Payerne BSRN station in Switzerland. The analysis was applied both to the whole dataset and data subsets reflecting particular conditions to allow a better understanding of how instrument performance depends on such conditions.The overall performance for measuring global horizontal irradiance (GHI is satisfactory with deviations compatible with an expanded uncertainty of ±25 Wm−2 (±10 %. For diffuse horizontal irradiance (DfHI, RSIs exhibited errors on the order of ±20 Wm−2 (±13 % with some of them being affected by small systematic negative biases on the order of −5 Wm−2 (median. SPN1s underestimate DfHI by about −10 Wm−2 (median with a relatively large range of the expanded error distribution between −45 Wm−2 and 20 Wm−2 (−35 % to 13 %. For direct normal irradiance (DNI, the extended error range for RSIs is on the order of ±40 Wm−2 (±5–6 % with some instruments presenting no bias while others are affected by median biases up to −15 Wm−2. SPN1s exhibit a relatively large median bias of 40 Wm−2, and an extended range of the error distribution between −45 Wm−2 and 125 Wm−2 (−6 % to 19 %. Typical errors on the integrated yearly energy per unit surface area are on the order of a few percent or less (< 5 % for RSI with negligible errors on DNI for some RSI instruments. SPN1 integrated errors are negligible for GHI, but on the order of −8 % for DfHI, and between 9 % and 11 % for DNI.For RSIs, GHI and DfHI errors showed

  4. A Neural Network Based Intelligent Predictive Sensor for Cloudiness, Solar Radiation and Air Temperature

    Science.gov (United States)

    Ferreira, Pedro M.; Gomes, João M.; Martins, Igor A. C.; Ruano, António E.

    2012-01-01

    Accurate measurements of global solar radiation and atmospheric temperature, as well as the availability of the predictions of their evolution over time, are important for different areas of applications, such as agriculture, renewable energy and energy management, or thermal comfort in buildings. For this reason, an intelligent, light-weight and portable sensor was developed, using artificial neural network models as the time-series predictor mechanisms. These have been identified with the aid of a procedure based on the multi-objective genetic algorithm. As cloudiness is the most significant factor affecting the solar radiation reaching a particular location on the Earth surface, it has great impact on the performance of predictive solar radiation models for that location. This work also represents one step towards the improvement of such models by using ground-to-sky hemispherical colour digital images as a means to estimate cloudiness by the fraction of visible sky corresponding to clouds and to clear sky. The implementation of predictive models in the prototype has been validated and the system is able to function reliably, providing measurements and four-hour forecasts of cloudiness, solar radiation and air temperature. PMID:23202230

  5. SREQP: A Solar Radiation Extraction and Query Platform for the Production and Consumption of Linked Data from Weather Stations Sensors

    Directory of Open Access Journals (Sweden)

    José Luis Sánchez-Cervantes

    2016-01-01

    Full Text Available Nowadays, solar radiation information is provided from sensors installed in different geographic locations and platforms of meteorological agencies. However, common formats such as PDF files and HTML documents to provide solar radiation information do not offer semantics in their content, and they may pose problems to integrate and fuse data from multiple resources. One of the challenges of sensors Web is the unification of data from multiple sources, although this type of information facilitates interoperability with other sensor Web systems. This research proposes architecture SREQP (Solar Radiation Extraction and Query Platform to extract solar radiation data from multiple external sources and merge them on a single and unique platform. SREQP makes use of Linked Data to generate a set of triples containing information about extracted data, which allows final users to query data through a SPARQL endpoint. The conceptual model was developed by using known vocabularies, such as SSN or WGS84. Moreover, an Analytic Hierarchy Process was carried out for the evaluation of SREQP in order to identify and evaluate the main features of Linked-Sensor-Data and the sensor Web systems. Results from the evaluation indicated that SREQP contained most of the features considered essential in Linked-Sensor-Data and sensor Web systems.

  6. Radiation sensor

    International Nuclear Information System (INIS)

    Brown, W.L.; Geronime, R.L.

    1977-01-01

    Radiation sensor and thermocouple, respectively, which can be used for reactor in-core instrumentation. The radiation sensor consists of an inconel conductor wire and rhodium emitter wire, the thermocouple of two intertwined alumel or chromel wires. Both are arranged in the center of a metal tube relative to which they are separated by an insulator made of SiO 2 fibers. This insulator is first introduced as a loose fabric between the radiation sensor and the thermocouple, respectively, and the metal tube and then compacted to a density of 35-73% of pure SiO 2 by drawing the tube. There is no need for soldering or welding. The insulation resistivity at room temperature ist between 10 14 and 10 15 ohms. (ORU) [de

  7. Air Temperature Error Correction Based on Solar Radiation in an Economical Meteorological Wireless Sensor Network.

    Science.gov (United States)

    Sun, Xingming; Yan, Shuangshuang; Wang, Baowei; Xia, Li; Liu, Qi; Zhang, Hui

    2015-07-24

    Air temperature (AT) is an extremely vital factor in meteorology, agriculture, military, etc., being used for the prediction of weather disasters, such as drought, flood, frost, etc. Many efforts have been made to monitor the temperature of the atmosphere, like automatic weather stations (AWS). Nevertheless, due to the high cost of specialized AT sensors, they cannot be deployed within a large spatial density. A novel method named the meteorology wireless sensor network relying on a sensing node has been proposed for the purpose of reducing the cost of AT monitoring. However, the temperature sensor on the sensing node can be easily influenced by environmental factors. Previous research has confirmed that there is a close relation between AT and solar radiation (SR). Therefore, this paper presents a method to decrease the error of sensed AT, taking SR into consideration. In this work, we analyzed all of the collected data of AT and SR in May 2014 and found the numerical correspondence between AT error (ATE) and SR. This corresponding relation was used to calculate real-time ATE according to real-time SR and to correct the error of AT in other months.

  8. Air Temperature Error Correction Based on Solar Radiation in an Economical Meteorological Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Xingming Sun

    2015-07-01

    Full Text Available Air temperature (AT is an extremely vital factor in meteorology, agriculture, military, etc., being used for the prediction of weather disasters, such as drought, flood, frost, etc. Many efforts have been made to monitor the temperature of the atmosphere, like automatic weather stations (AWS. Nevertheless, due to the high cost of specialized AT sensors, they cannot be deployed within a large spatial density. A novel method named the meteorology wireless sensor network relying on a sensing node has been proposed for the purpose of reducing the cost of AT monitoring. However, the temperature sensor on the sensing node can be easily influenced by environmental factors. Previous research has confirmed that there is a close relation between AT and solar radiation (SR. Therefore, this paper presents a method to decrease the error of sensed AT, taking SR into consideration. In this work, we analyzed all of the collected data of AT and SR in May 2014 and found the numerical correspondence between AT error (ATE and SR. This corresponding relation was used to calculate real-time ATE according to real-time SR and to correct the error of AT in other months.

  9. Wireless radiation sensor

    Science.gov (United States)

    Lamberti, Vincent E.; Howell, Jr, Layton N.; Mee, David K.; Kress, Reid L.

    2016-08-09

    Disclosed is a sensor for detecting radiation. The sensor includes a ferromagnetic metal and a radiation sensitive material coupled to the ferromagnetic metal. The radiation sensitive material is operable to change a tensile stress of the ferromagnetic metal upon exposure to radiation. The radiation is detected based on changes in the magnetic switching characteristics of the ferromagnetic metal caused by the changes in the tensile stress.

  10. Solar radiation over India

    Energy Technology Data Exchange (ETDEWEB)

    Mani, A; Rangarajan, S

    1982-01-01

    Solar radiation data, on horizontal and sloped surfaces, are provided derived from other meteorological parameters at 145 stations covering all major climatic zones of the country. Two methods were used to compute solar radiation, one using regression techniques to derive radiation from sunshine and cloudiness, the other from extra-terrestrial radiation, allowing for its depletion by absorption and scattering in the atmosphere. The methods of calculating the daily global radiation tilt factor using an anisotropic model for diffuse solar radiation are described. The results of statistical analysis of global solar radiation data recorded at 16 stations are presented. Appendices contain an extensive bibliograpny, sun path diagrams for latitudes 6/sup 0/N to 36/sup 0/N, and tables for the calculation of Local Apparent Time from Indian Standard Time.

  11. Coordinated weather balloon solar radiation measurements during a solar eclipse.

    Science.gov (United States)

    Harrison, R G; Marlton, G J; Williams, P D; Nicoll, K A

    2016-09-28

    Solar eclipses provide a rapidly changing solar radiation environment. These changes can be studied using simple photodiode sensors, if the radiation reaching the sensors is unaffected by cloud. Transporting the sensors aloft using standard meteorological instrument packages modified to carry extra sensors, provides one promising but hitherto unexploited possibility for making solar eclipse radiation measurements. For the 20 March 2015 solar eclipse, a coordinated campaign of balloon-carried solar radiation measurements was undertaken from Reading (51.44°N, 0.94°W), Lerwick (60.15°N, 1.13°W) and Reykjavik (64.13°N, 21.90°W), straddling the path of the eclipse. The balloons reached sufficient altitude at the eclipse time for eclipse-induced variations in solar radiation and solar limb darkening to be measured above cloud. Because the sensor platforms were free to swing, techniques have been evaluated to correct the measurements for their changing orientation. In the swing-averaged technique, the mean value across a set of swings was used to approximate the radiation falling on a horizontal surface; in the swing-maximum technique, the direct beam was estimated by assuming that the maximum solar radiation during a swing occurs when the photodiode sensing surface becomes normal to the direction of the solar beam. Both approaches, essentially independent, give values that agree with theoretical expectations for the eclipse-induced radiation changes.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'. © 2016 The Authors.

  12. Wireless passive radiation sensor

    Science.gov (United States)

    Pfeifer, Kent B; Rumpf, Arthur N; Yelton, William G; Limmer, Steven J

    2013-12-03

    A novel measurement technique is employed using surface acoustic wave (SAW) devices, passive RF, and radiation-sensitive films to provide a wireless passive radiation sensor that requires no batteries, outside wiring, or regular maintenance. The sensor is small (<1 cm.sup.2), physically robust, and will operate unattended for decades. In addition, the sensor can be insensitive to measurement position and read distance due to a novel self-referencing technique eliminating the need to measure absolute responses that are dependent on RF transmitter location and power.

  13. Irradiance sensors for solar systems

    Energy Technology Data Exchange (ETDEWEB)

    Storch, A.; Schindl, J. [Oesterreichisches Forschungs- und Pruefzentrum Arsenal GesmbH, Vienna (Austria). Business Unit Renewable Energy

    2004-07-01

    The presented project surveyed the quality of irradiance sensors used for applications in solar systems. By analysing an outdoor measurement, the accuracies of ten commercially available irradiance sensors were evaluated, comparing their results to those of a calibrated Kipp and Zonen pyranometer CM21. Furthermore, as a simple method for improving the quality of the results, for each sensor an irradiance-calibration was carried out and examined for its effectiveness. (orig.)

  14. Radiation-activated sensor

    International Nuclear Information System (INIS)

    Nirschl, J.C.

    1976-01-01

    A sensing system is described for use in a remote location which detects electromagnetic radiation energy, the system being self-activating, turning itself automatically on and off, as a function of radiation intensity across the detector. In essence, when no radiation is present across the detector, the system will consume no power, the switches and MOSFET discriminator being essentially in an ''off'' position. Radiation across the detector provides a current to an input capacitance which when charged turns on the switch and the MOSFET discriminator. A switch driver produces an output pulse showing the presence of radiation; the system then shuts off awaiting the next radiation input. Since the sensor system uses virtually no power unless radiation is present, it is ideally suited for use in remote environments where battery power and size is a predominant consideration. 2 claims, 3 drawing figures

  15. Measurement tolerance analysis of solar radiation

    Energy Technology Data Exchange (ETDEWEB)

    Cimo, J.; Maderkova, L.; Horak, J.; Igaz, D.; Pasztorova, S. [Department of Biomereorlogy and Hydrology, Slovak Agriculture University, Nitra (Slovakia)

    2012-07-01

    Solar radiant energy is bane and almost the only one source of heat for Earth 's surface and for atmosphere, and almost the only one source of energy for physical processes. Solar energy is one of the most available and the most ecological energy source. Currently the firm Kipp and Zonen belongs to prominent producer of sensors for measuring of global radiation. These sensors are the most used in our country and also in network of meteorological measurements of WMO. Therefore the two types of measuring sensors for global radiation (pyranometer PMP6, CMP 11) in comparison with calculation method Savin-Angstrom are analysed. (author)

  16. Solar constant values for estimating solar radiation

    International Nuclear Information System (INIS)

    Li, Huashan; Lian, Yongwang; Wang, Xianlong; Ma, Weibin; Zhao, Liang

    2011-01-01

    There are many solar constant values given and adopted by researchers, leading to confusion in estimating solar radiation. In this study, some solar constant values collected from literature for estimating solar radiation with the Angstroem-Prescott correlation are tested in China using the measured data between 1971 and 2000. According to the ranking method based on the t-statistic, a strategy to select the best solar constant value for estimating the monthly average daily global solar radiation with the Angstroem-Prescott correlation is proposed. -- Research highlights: → The effect of the solar constant on estimating solar radiation is investigated. → The investigation covers a diverse range of climate and geography in China. → A strategy to select the best solar constant for estimating radiation is proposed.

  17. Solar cell radiation handbook

    Science.gov (United States)

    Tada, H. Y.; Carter, J. R., Jr.; Anspaugh, B. E.; Downing, R. G.

    1982-01-01

    The handbook to predict the degradation of solar cell electrical performance in any given space radiation environment is presented. Solar cell theory, cell manufacturing and how they are modeled mathematically are described. The interaction of energetic charged particles radiation with solar cells is discussed and the concept of 1 MeV equivalent electron fluence is introduced. The space radiation environment is described and methods of calculating equivalent fluences for the space environment are developed. A computer program was written to perform the equivalent fluence calculations and a FORTRAN listing of the program is included. Data detailing the degradation of solar cell electrical parameters as a function of 1 MeV electron fluence are presented.

  18. The Next Spaceflight Solar Irradiance Sensor: TSIS

    Science.gov (United States)

    Kopp, Greg; Pilewskie, Peter; Richard, Erik

    2016-05-01

    The Total and Spectral Solar Irradiance Sensor (TSIS) will continue measurements of the solar irradiance with improved accuracies and stabilities over extant spaceflight instruments. The two TSIS solar-observing instruments include the Total Irradiance Monitor (TIM) and the Spectral Irradiance Monitor (SIM) for measuring total- and spectral- solar-irradiance, respectively. The former provides the net energy powering the Earth’s climate system while the latter helps attribute where that energy is absorbed by the Earth’s atmosphere and surface. Both spaceflight instruments are assembled and being prepared for integration on the International Space Station. With operations commencing in late 2017, the TSIS is intended to overlap with NASA’s ongoing SOlar Radiation and Climate Experiment (SORCE) mission, which launched in 2003 and contains the first versions of both the TIM and SIM instruments, as well as with the TSI Calibration Transfer Experiment (TCTE), which began total solar irradiance measurements in 2013. We summarize the TSIS’s instrument improvements and intended solar-irradiance measurements.

  19. Solar ultraviolet radiation cataract.

    Science.gov (United States)

    Löfgren, Stefan

    2017-03-01

    Despite being a treatable disease, cataract is still the leading cause for blindness in the world. Solar ultraviolet radiation is epidemiologically linked to cataract development, while animal and in vitro studies prove a causal relationship. However, the pathogenetic pathways for the disease are not fully understood and there is still no perfect model for human age related cataract. This non-comprehensive overview focus on recent developments regarding effects of solar UV radiation wavebands on the lens. A smaller number of fundamental papers are also included to provide a backdrop for the overview. Future studies are expected to further clarify the cellular and subcellular mechanisms for UV radiation-induced cataract and especially the isolated or combined temporal and spatial effects of UVA and UVB in the pathogenesis of human cataract. Regardless of the cause for cataract, there is a need for advances in pharmaceutical or other treatment modalities that do not require surgical replacement of the lens. Copyright © 2016. Published by Elsevier Ltd.

  20. Parameterization models for solar radiation and solar technology applications

    International Nuclear Information System (INIS)

    Khalil, Samy A.

    2008-01-01

    Solar radiation is very important for the evaluation and wide use of solar renewable energy systems. The development of calibration procedures for broadband solar radiation photometric instrumentation and the improvement of broadband solar radiation measurement accuracy have been done. An improved diffuse sky reference and photometric calibration and characterization software for outdoor pyranometer calibrations are outlined. Parameterizations for direct beam, total hemispherical and diffuse sky radiation and solar radiation technology are briefly reviewed. The uncertainties for various broadband solar radiations of solar energy and atmospheric effects are discussed. The varying responsivities of solar radiation with meteorological, statistical and climatological parameters and possibility atmospheric conditions was examined

  1. Parameterization models for solar radiation and solar technology applications

    Energy Technology Data Exchange (ETDEWEB)

    Khalil, Samy A. [National Research Institute of Astronomy and Geophysics, Solar and Space Department, Marsed Street, Helwan, 11421 Cairo (Egypt)

    2008-08-15

    Solar radiation is very important for the evaluation and wide use of solar renewable energy systems. The development of calibration procedures for broadband solar radiation photometric instrumentation and the improvement of broadband solar radiation measurement accuracy have been done. An improved diffuse sky reference and photometric calibration and characterization software for outdoor pyranometer calibrations are outlined. Parameterizations for direct beam, total hemispherical and diffuse sky radiation and solar radiation technology are briefly reviewed. The uncertainties for various broadband solar radiations of solar energy and atmospheric effects are discussed. The varying responsivities of solar radiation with meteorological, statistical and climatological parameters and possibility atmospheric conditions was examined. (author)

  2. Robust Solar Position Sensor for Tracking Systems

    DEFF Research Database (Denmark)

    Ritchie, Ewen; Argeseanu, Alin; Leban, Krisztina Monika

    2009-01-01

    The paper proposes a new solar position sensor used in tracking system control. The main advantages of the new solution are the robustness and the economical aspect. Positioning accuracy of the tracking system that uses the new sensor is better than 1°. The new sensor uses the ancient principle...... of the solar clock. The sensitive elements are eight ordinary photo-resistors. It is important to note that all the sensors are not selected simultaneously. It is not necessary for sensor operating characteristics to be quasi-identical because the sensor principle is based on extreme operating duty measurement...... (bright or dark). In addition, the proposed solar sensor significantly simplifies the operation of the tracking control device....

  3. Solar and infrared radiation measurements

    CERN Document Server

    Vignola, Frank; Michalsky, Joseph

    2012-01-01

    The rather specialized field of solar and infrared radiation measurement has become more and more important in the face of growing demands by the renewable energy and climate change research communities for data that are more accurate and have increased temporal and spatial resolution. Updating decades of acquired knowledge in the field, Solar and Infrared Radiation Measurements details the strengths and weaknesses of instruments used to conduct such solar and infrared radiation measurements. Topics covered include: Radiometer design and performance Equipment calibration, installation, operati

  4. About Solar Radiation Intensity Measurements and Data Processing

    Directory of Open Access Journals (Sweden)

    MICH-VANCEA Claudiu

    2012-10-01

    Full Text Available Measuring the intensity of solar radiation is one of the directions of investigation necessary for the implementation of photovoltaic systems in a particular geographical area. This can be done by using specific measuring equipment (pyranometer sensors based onthermal or photovoltaic principle. In this paper it is presented a method for measuring solar radiation (which has two main components - direct radiation and diffuse radiation with sensors based on photovoltaic principle. Such data are processed for positioning solarpanels, in order their efficiency to be maximized.

  5. Solar radiation absorbing material

    Science.gov (United States)

    Googin, John M.; Schmitt, Charles R.; Schreyer, James M.; Whitehead, Harlan D.

    1977-01-01

    Solar energy absorbing means in solar collectors are provided by a solar selective carbon surface. A solar selective carbon surface is a microporous carbon surface having pores within the range of 0.2 to 2 micrometers. Such a surface is provided in a microporous carbon article by controlling the pore size. A thermally conductive substrate is provided with a solar selective surface by adhering an array of carbon particles in a suitable binder to the substrate, a majority of said particles having diameters within the range of about 0.2-10 microns.

  6. A sensor element for direct radiation measurement

    Energy Technology Data Exchange (ETDEWEB)

    Bajons, P.; Wernhart, U.; Zeiler, H. [University of Vienna (Austria). Institut of Material Physics

    1998-08-01

    A combination of a photodiode with a nonimaging light concentrator is developed to perform measurements of the direct solar radiation component. A prototype composed of low price elements is taken as a starting point to discuss the problems which must be faced when calibrating such sensors. By this the influence of the angle of incidence and spectral distribution (caused by different air mass or varying degree of clearness) of the incident radiation on the behavior of the system is studied. The readings are compared to the calculated (global minus diffuse) readings obtained from two standard star pyranometers. Finally the possibilities for increasing the accuracy of the sensor element and for applying the device are discussed. (author)

  7. Models of diffuse solar radiation

    Energy Technology Data Exchange (ETDEWEB)

    Boland, John; Ridley, Barbara [Centre for Industrial and Applied Mathematics, University of South Australia, Mawson Lakes Boulevard, Mawson Lakes, SA 5095 (Australia); Brown, Bruce [Department of Statistics and Applied Probability, National University of Singapore, Singapore 117546 (Singapore)

    2008-04-15

    For some locations both global and diffuse solar radiation are measured. However, for many locations, only global is measured, or inferred from satellite data. For modelling solar energy applications, the amount of radiation on a tilted surface is needed. Since only the direct component on a tilted surface can be calculated from trigonometry, we need to have diffuse on the horizontal available. There are regression relationships for estimating the diffuse on a tilted surface from diffuse on the horizontal. Models for estimating the diffuse radiation on the horizontal from horizontal global that have been developed in Europe or North America have proved to be inadequate for Australia [Spencer JW. A comparison of methods for estimating hourly diffuse solar radiation from global solar radiation. Sol Energy 1982; 29(1): 19-32]. Boland et al. [Modelling the diffuse fraction of global solar radiation on a horizontal surface. Environmetrics 2001; 12: 103-16] developed a validated model for Australian conditions. We detail our recent advances in developing the theoretical framework for the approach reported therein, particularly the use of the logistic function instead of piecewise linear or simple nonlinear functions. Additionally, we have also constructed a method, using quadratic programming, for identifying values that are likely to be erroneous. This allows us to eliminate outliers in diffuse radiation values, the data most prone to errors in measurement. (author)

  8. Radiation hard solar cell and array

    International Nuclear Information System (INIS)

    Russell, R.L.

    1975-01-01

    A power generating solar cell for a spacecraft solar array is hardened against transient response to nuclear radiation while permitting normal operation of the cell in a solar radiation environment by shunting the cell with a second solar cell whose contacts are reversed relative to the power cell to form a cell module, exposing the power cell only to the solar radiation in a solar radiation environment to produce an electrical output at the module terminals, and exposing both cells to the nuclear radiation in a nuclear radiation environment so that the radiation induced currents generated by the cells suppress one another

  9. Detecting solar chameleons through radiation pressure

    CERN Document Server

    Baum, S.; Hoffmann, D.H.H.; Karuza, M.; Semertzidis, Y.K.; Upadhye, A.; Zioutas, K.

    2014-10-24

    Light scalar fields can drive the accelerated expansion of the universe. Hence, they are obvious dark energy candidates. To make such models compatible with tests of General Relativity in the solar system and "fifth force" searches on Earth, one needs to screen them. One possibility is the so-called "chameleon" mechanism, which renders an effective mass depending on the local matter density. If chameleon particles exist, they can be produced in the sun and detected on earth exploiting the equivalent of a radiation pressure. Since their effective mass scales with the local matter density, chameleons can be reflected by a dense medium if their effective mass becomes greater than their total energy. Thus, under appropriate conditions, a flux of solar chameleons may be sensed by detecting the total instantaneous momentum transferred to a suitable opto-mechanical force/pressure sensor. We calculate the solar chameleon spectrum and the reach in the chameleon parameter space of an experiment using the preliminary re...

  10. Detecting solar chameleons through radiation pressure

    CERN Document Server

    Baum, Sebastian

    2014-01-01

    Light scalar fields can drive accelerated expansion of the universe. Hence, scalars are obvious dark energy candidates. To make these models compatible with test of General Relativity in the solar system and fifth force searches on earth, one needs to screen them. One possibility is the chameleon mechanism, which renders an effective mass depending on the local energy density. If chameleons exist, they can be produced in the sun and detected on earth through their radiation pressure. We calculate the solar chameleon spectrum and the sensitivity of an experiment to be carried out at CAST, CERN, utilizing a radiation pressure sensor currently under development at INFN, Trieste. We show that such an experiment will be sensitive to a wide range of model parameters and signifies a pioneering effort searching for chameleons in unprobed paramterspace.

  11. Solar radiation on domed roofs

    Energy Technology Data Exchange (ETDEWEB)

    Faghih, Ahmadreza K.; Bahadori, Mehdi N. [School of Mechanical Engineering, Sharif University of Technology, Tehran (Iran)

    2009-11-15

    Solar radiation received and absorbed by four domed roofs was estimated and compared with that of a flat roof. The domed roofs all had the same base areas, and equal to that of the flat roof. One of the roofs considered was the dome of the St. Peter's Church in Rome. Compared with the other roofs considered, this dome had a higher aspect ratio. It was found that all domed roofs received more solar radiation than the flat roof. Considering glazed tiles to cover a selected dome in Iran and the dome of the St. Peter's Church, it was found that the solar radiation absorbed by these roofs is reduced appreciably. In the case of the dome of St. Peter's Church, the amount of radiation absorbed was roughly equal to that absorbed by the comparable flat roof in the warm months. In the case of the glazed reference dome located in Yazd, Iran (a city with very high solar radiation), the radiation absorbed was less than that of flat roof at all times. In addition to aesthetics, this may be a reason for employing glazed tiles to cover the domes of all mosques, shrines, and other large buildings in Iran. (author)

  12. Estimating solar radiation in Ghana

    International Nuclear Information System (INIS)

    Anane-Fenin, K.

    1986-04-01

    The estimates of global radiation on a horizontal surface for 9 towns in Ghana, West Africa, are deduced from their sunshine data using two methods developed by Angstrom and Sabbagh. An appropriate regional parameter is determined with the first method and used to predict solar irradiation in all the 9 stations with an accuracy better than 15%. Estimation of diffuse solar irradiation by Page, Lin and Jordan and three other authors' correlation are performed and the results examined. (author)

  13. NEW MODEL FOR SOLAR RADIATION ESTIMATION FROM ...

    African Journals Online (AJOL)

    NEW MODEL FOR SOLAR RADIATION ESTIMATION FROM MEASURED AIR TEMPERATURE AND ... Nigerian Journal of Technology ... Solar radiation measurement is not sufficient in Nigeria for various reasons such as maintenance and ...

  14. SORCE: Solar Radiation and Climate Experiment

    Science.gov (United States)

    Cahalan, Robert; Rottman, Gary; Lau, William K. M. (Technical Monitor)

    2002-01-01

    Contents include the following: Understanding the Sun's influence on the Earth; How the Sun affect Earth's climate; By how much does the Sun's radiation very; Understanding Solar irradiance; History of Solar irradiance observations; The SORCE mission; How do the SORCE instruments measure solar radiation; Total irradiance monitor (TIM); Spectral irradiance monitor (SIM); Solar stellar irradiance comparison experiment (SOLSTICE); XUV photometer system (XPS).

  15. Snow, ice and solar radiation

    NARCIS (Netherlands)

    Kuipers Munneke, P.

    2009-01-01

    The snow-covered ice sheets of Antarctica and Greenland reflect most of the incoming solar radiation. The reflectivity, commonly called the albedo, of snow on these ice sheets has been observed to vary in space and time. In this thesis, temporal and spatial changes in snow albedo is found to depend

  16. Solar and Net Radiation for Estimating Potential Evaporation from Three Vegetation Canopies

    Science.gov (United States)

    D.M. Amatya; R.W. Skaggs; G.W. Cheschier; G.P. Fernandez

    2000-01-01

    Solar and net radiation data are frequent/y used in estimating potential evaporation (PE) from various vegetative surfaces needed for water balance and hydrologic modeling studies. Weather parameters such as air temperature, relative humidity, wind speed, solar radiation, and net radiation have been continuously monitored using automated sensors to estimate PE for...

  17. Detecting solar chameleons through radiation pressure

    International Nuclear Information System (INIS)

    Baum, S.; Cantatore, G.; Hoffmann, D.H.H.; Karuza, M.; Semertzidis, Y.K.; Upadhye, A.; Zioutas, K.

    2014-01-01

    Light scalar fields can drive the accelerated expansion of the universe. Hence, they are obvious dark energy candidates. To make such models compatible with tests of General Relativity in the solar system and “fifth force” searches on Earth, one needs to screen them. One possibility is the so-called “chameleon” mechanism, which renders an effective mass depending on the local matter density. If chameleon particles exist, they can be produced in the sun and detected on Earth exploiting the equivalent of a radiation pressure. Since their effective mass scales with the local matter density, chameleons can be reflected by a dense medium if their effective mass becomes greater than their total energy. Thus, under appropriate conditions, a flux of solar chameleons may be sensed by detecting the total instantaneous momentum transferred to a suitable opto-mechanical force/pressure sensor. We calculate the solar chameleon spectrum and the reach in the chameleon parameter space of an experiment using the preliminary results from a force/pressure sensor, currently under development at INFN Trieste, to be mounted in the focal plane of one of the X-Ray telescopes of the CAST experiment at CERN. We show, that such an experiment signifies a pioneering effort probing uncharted chameleon parameter space

  18. Detecting solar chameleons through radiation pressure

    Energy Technology Data Exchange (ETDEWEB)

    Baum, S., E-mail: sebastian.baum@cern.ch [Uppsala Universitet, Box 516, SE 75120, Uppsala (Sweden); European Organization for Nuclear Research (CERN), Gèneve (Switzerland); Cantatore, G. [Università di Trieste, Via Valerio 2, 34127 Trieste (Italy); INFN Trieste, Padriciano 99, 34149 Trieste (Italy); Hoffmann, D.H.H. [Institut für Kernphysik, TU-Darmstadt, Schlossgartenstr. 9, D-64289 Darmstadt (Germany); Karuza, M. [INFN Trieste, Padriciano 99, 34149 Trieste (Italy); Phys. Dept. and CMNST, University of Rijeka, R. Matejcic 2, Rijeka (Croatia); Semertzidis, Y.K. [Center for Axion and Precision Physics Research (IBS), Daejeon 305-701 (Korea, Republic of); Department of Physics, KAIST, Daejeon 305-701 (Korea, Republic of); Upadhye, A. [Physics Department, University of Wisconsin–Madison, 1150 University Avenue, Madison, WI 53706 (United States); Zioutas, K., E-mail: konstantin.zioutas@cern.ch [European Organization for Nuclear Research (CERN), Gèneve (Switzerland); University of Patras, GR 26504 Patras (Greece)

    2014-12-12

    Light scalar fields can drive the accelerated expansion of the universe. Hence, they are obvious dark energy candidates. To make such models compatible with tests of General Relativity in the solar system and “fifth force” searches on Earth, one needs to screen them. One possibility is the so-called “chameleon” mechanism, which renders an effective mass depending on the local matter density. If chameleon particles exist, they can be produced in the sun and detected on Earth exploiting the equivalent of a radiation pressure. Since their effective mass scales with the local matter density, chameleons can be reflected by a dense medium if their effective mass becomes greater than their total energy. Thus, under appropriate conditions, a flux of solar chameleons may be sensed by detecting the total instantaneous momentum transferred to a suitable opto-mechanical force/pressure sensor. We calculate the solar chameleon spectrum and the reach in the chameleon parameter space of an experiment using the preliminary results from a force/pressure sensor, currently under development at INFN Trieste, to be mounted in the focal plane of one of the X-Ray telescopes of the CAST experiment at CERN. We show, that such an experiment signifies a pioneering effort probing uncharted chameleon parameter space.

  19. Radiating properties of solar plasmas

    Science.gov (United States)

    Bruner, M. E.; Mcwhirter, R. W. P.

    1988-01-01

    Using a series of 14 previously obtained empirical emission measure distributions and a number of spectral lines observed by the SMM and P78-1 instruments, the total power radiated by a hot plasma is compared to that radiated by individual spectrum lines. Results are presented for different choices of ionization balance and power loss functions. The results indicate that for some lines such as the C IV resonance doublet at 1548 A and 1550 A, the ratio of the line intensity to the total radiated power varied only over a factor of 2, suggesting that well-calibrated measurements of a single line intensity may provide a fairly good estimation of the total radiated power output from the solar plasma.

  20. Radiating properties of solar plasmas

    International Nuclear Information System (INIS)

    Bruner, M.E.; Mcwhirter, R.W.P.

    1988-01-01

    Using a series of 14 previously obtained empirical emission measure distributions and a number of spectral lines observed by the SMM and P78-1 instruments, the total power radiated by a hot plasma is compared to that radiated by individual spectrum lines. Results are presented for different choices of ionization balance and power loss functions. The results indicate that for some lines such as the C IV resonance doublet at 1548 A and 1550 A, the ratio of the line intensity to the total radiated power varied only over a factor of 2, suggesting that well-calibrated measurements of a single line intensity may provide a fairly good estimation of the total radiated power output from the solar plasma. 21 references

  1. Listing of solar radiation measuring equipment and glossary

    Science.gov (United States)

    Carter, E. A.; Greenbaum, S. A.; Patel, A. M.

    1976-01-01

    An attempt is made to list and provide all available information about solar radiation measuring equipment which are being manufactured and are available on the market. The list is in tabular form and includes sensor type, response time, cost data and comments for each model. A cost code is included which shows ranges only.

  2. Self-calibrating solar position sensor

    Science.gov (United States)

    Maxey, Lonnie Curt

    2018-01-30

    A sun positioning sensor and method of accurately tracking the sun are disclosed. The sensor includes a position sensing diode and a disk having a body defining an aperture for accepting solar light. An extension tube having a body that defines a duct spaces the position sensing diode from the disk such that the solar light enters the aperture in the disk, travels through the duct in the extension tube and strikes the position sensing diode. The extension tube has a known length that is fixed. Voltage signals indicative of the location and intensity of the sun are generated by the position sensing diode. If it is determined that the intensity values are unreliable, then historical position values are used from a table. If the intensity values are deemed reliable, then actual position values are used from the position sensing diode.

  3. Solar radiation for Mars power systems

    Science.gov (United States)

    Appelbaum, Joseph; Landis, Geoffrey A.

    1991-01-01

    Detailed information about the solar radiation characteristics on Mars are necessary for effective design of future planned solar energy systems operating on the surface of Mars. A procedure and solar radiation related data from which the diurnally and daily variation of the global, direct (or beam), and diffuse insolation on Mars are calculated, are presented. The radiation data are based on measured optical depth of the Martian atmosphere derived from images taken of the Sun with a special diode on the Viking Lander cameras; and computation based on multiple wavelength and multiple scattering of the solar radiation.

  4. Parameterization Of Solar Radiation Using Neural Network

    International Nuclear Information System (INIS)

    Jiya, J. D.; Alfa, B.

    2002-01-01

    This paper presents a neural network technique for parameterization of global solar radiation. The available data from twenty-one stations is used for training the neural network and the data from other ten stations is used to validate the neural model. The neural network utilizes latitude, longitude, altitude, sunshine duration and period number to parameterize solar radiation values. The testing data was not used in the training to demonstrate the performance of the neural network in unknown stations to parameterize solar radiation. The results indicate a good agreement between the parameterized solar radiation values and actual measured values

  5. Calculating the diffuse solar radiation in regions without solar radiation measurements

    International Nuclear Information System (INIS)

    Li, Huashan; Bu, Xianbiao; Long, Zhen; Zhao, Liang; Ma, Weibin

    2012-01-01

    Correlations for calculating diffuse solar radiation can be classified into models with global solar radiation (H-based method) and without it (Non-H method). The objective of the present study is to compare the performance of H-based and Non-H methods for calculating the diffuse solar radiation in regions without solar radiation measurements. The comparison is carried out at eight meteorological stations in China focusing on the monthly average daily diffuse solar radiation. Based on statistical error tests, the results show that the Non-H method that includes other readily available meteorological elements gives better estimates. Therefore, it can be concluded that the Non-H method is more appropriate than the H-based one for calculating the diffuse solar radiation in regions without solar radiation measurements. -- Highlights: ► Methods for calculating diffuse solar radiation in regions without solar radiation measurements are investigated. ► Diffuse solar radiation models can be classified into two groups according to global solar radiation. ► Two approaches are compared at the eight meteorological stations in China. ► The method without global solar radiation is recommended.

  6. Solar radiation and human health

    International Nuclear Information System (INIS)

    Juzeniene, Asta; Moan, Kristin; Moan, Johan; Brekke, Paal; Dahlback, Arne; Andersson-Engels, Stefan; Reichrath, Joerg; Holick, Michael F; Grant, William B

    2011-01-01

    The Sun has played a major role in the development of life on Earth. In Western culture, people are warned against Sun exposure because of its adverse effects: erythema, photoimmunosuppression, photoageing, photocarcinogenesis, cataracts and photokeratitis. However, Sun exposure is also beneficial, since moderate doses give beneficial physiological effects: vitamin D synthesis, reduction of blood pressure and mental health. Shortage of Sun exposure may be even more dangerous to human health than excessive exposure. Avoiding Sun exposure leads to vitamin D deficiency which is associated not only with rickets and osteomalacia, but also with increased risk of cardiovascular disease, multiple sclerosis, rheumatoid arthritis, diabetes, influenza, many types of cancer and adverse pregnancy outcomes. Solar radiation induces nitric oxide release in tissue and immediate pigment darkening which certainly play important roles, although these are still unknown. Action spectra relevant for health are described. We will also review what is known about spectral and intensity variations of terrestrial solar radiation as well as its penetration through the atmosphere and into human skin and tissue.

  7. Solar radiation and human health

    Energy Technology Data Exchange (ETDEWEB)

    Juzeniene, Asta; Moan, Kristin; Moan, Johan [Department of Radiation Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, N-0310 Oslo (Norway); Brekke, Paal [Norwegian Space Centre, PO Box 113, Skoeyen, N-0212 Oslo (Norway); Dahlback, Arne [Department of Physics, University of Oslo, Blindern, 0316 Oslo (Norway); Andersson-Engels, Stefan [Department of Physics, Lund University, PO Box 118, SE-221 00 Lund (Sweden); Reichrath, Joerg [Klinik fuer Dermatologie, Venerologie und Allergologie, Universitaetsklinikum des Saarlandes, D-66421 Homburg/Saar (Germany); Holick, Michael F [Department of Medicine, Section of Endocrinology, Nutrition and Diabetes, Vitamin D, Skin and Bone Research Laboratory, Boston University Medical Center, 85 E. Newton St., M-1013, Boston, MA 02118 (United States); Grant, William B, E-mail: asta.juzeniene@rr-research.no, E-mail: kmoan@hotmail.com, E-mail: paal.brekke@spacecentre.no, E-mail: arne.dahlback@fys.uio.no, E-mail: j.e.moan@fys.uio.no, E-mail: stefan.andersson-engels@fysik.lth.se, E-mail: joerg.reichrath@uks.eu, E-mail: mfholick@bu.edu, E-mail: wbgrant@infionline.net [Sunlight, Nutrition and Health Research Center (SUNARC), PO Box 641603, San Francisco, CA 94164-1603 (United States)

    2011-06-15

    The Sun has played a major role in the development of life on Earth. In Western culture, people are warned against Sun exposure because of its adverse effects: erythema, photoimmunosuppression, photoageing, photocarcinogenesis, cataracts and photokeratitis. However, Sun exposure is also beneficial, since moderate doses give beneficial physiological effects: vitamin D synthesis, reduction of blood pressure and mental health. Shortage of Sun exposure may be even more dangerous to human health than excessive exposure. Avoiding Sun exposure leads to vitamin D deficiency which is associated not only with rickets and osteomalacia, but also with increased risk of cardiovascular disease, multiple sclerosis, rheumatoid arthritis, diabetes, influenza, many types of cancer and adverse pregnancy outcomes. Solar radiation induces nitric oxide release in tissue and immediate pigment darkening which certainly play important roles, although these are still unknown. Action spectra relevant for health are described. We will also review what is known about spectral and intensity variations of terrestrial solar radiation as well as its penetration through the atmosphere and into human skin and tissue.

  8. Solar radiation and human health

    Science.gov (United States)

    Juzeniene, Asta; Brekke, Pål; Dahlback, Arne; Andersson-Engels, Stefan; Reichrath, Jörg; Moan, Kristin; Holick, Michael F.; Grant, William B.; Moan, Johan

    2011-06-01

    The Sun has played a major role in the development of life on Earth. In Western culture, people are warned against Sun exposure because of its adverse effects: erythema, photoimmunosuppression, photoageing, photocarcinogenesis, cataracts and photokeratitis. However, Sun exposure is also beneficial, since moderate doses give beneficial physiological effects: vitamin D synthesis, reduction of blood pressure and mental health. Shortage of Sun exposure may be even more dangerous to human health than excessive exposure. Avoiding Sun exposure leads to vitamin D deficiency which is associated not only with rickets and osteomalacia, but also with increased risk of cardiovascular disease, multiple sclerosis, rheumatoid arthritis, diabetes, influenza, many types of cancer and adverse pregnancy outcomes. Solar radiation induces nitric oxide release in tissue and immediate pigment darkening which certainly play important roles, although these are still unknown. Action spectra relevant for health are described. We will also review what is known about spectral and intensity variations of terrestrial solar radiation as well as its penetration through the atmosphere and into human skin and tissue.

  9. Solar radiation on Mars: Stationary photovoltaic array

    Science.gov (United States)

    Appelbaum, J.; Sherman, I.; Landis, G. A.

    1993-01-01

    Solar energy is likely to be an important power source for surface-based operation on Mars. Photovoltaic cells offer many advantages. In this article we have presented analytical expressions and solar radiation data for stationary flat surfaces (horizontal and inclined) as a function of latitude, season and atmospheric dust load (optical depth). The diffuse component of the solar radiation on Mars can be significant, thus greatly affecting the optimal inclination angle of the photovoltaic surface.

  10. Tm2+ luminescent materials for solar radiation conversion devices

    NARCIS (Netherlands)

    Van der Kolk, E.

    2015-01-01

    A solar radiation conversion device is described that comprises a luminescent Tm 2+ inorganic material for converting solar radiation of at least part of the UV and/or visible and/or infra red solar spectrum into infrared solar radiation, preferably said infrared solar radiation having a wavelength

  11. Workshop Report on Managing Solar Radiation

    Science.gov (United States)

    Lane, Lee (Compiler); Caldeira, Ken (Compiler); Chatfield, Robert (Compiler); Langhoff, Stephanie (Compiler)

    2007-01-01

    The basic concept of managing Earth's radiation budget is to reduce the amount of incoming solar radiation absorbed by the Earth so as to counterbalance the heating of the Earth that would otherwise result from the accumulation of greenhouse gases. The workshop did not seek to decide whether or under what circumstances solar radiation management should be deployed or which strategies or technologies might be best, if it were deployed. Rather, the workshop focused on defining what kinds of information might be most valuable in allowing policy makers more knowledgeably to address the various options for solar radiation management.

  12. Recent results on CVD diamond radiation sensors

    Science.gov (United States)

    Weilhammer, P.; Adam, W.; Bauer, C.; Berdermann, E.; Bogani, F.; Borchi, E.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; v. d. Eijk, R.; van Eijk, B.; Fallou, A.; Fish, D.; Fried, M.; Gan, K. K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Kass, R.; Knopfle, K. T.; Krammer, M.; Manfredi, P. F.; Meier, D.; LeNormand; Pan, L. S.; Pernegger, H.; Pernicka, M.; Plano, R.; Re, V.; Riester, J. L.; Roe, S.; Roff; Rudge, A.; Schieber, M.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Tapper, R. J.; Tesarek, R.; Thomson, G. B.; Trawick, M.; Trischuk, W.; Turchetta, R.; RD 42 Collaboration

    1998-02-01

    CVD diamond radiation sensors are being developed for possible use in trackers in the LHC experiments. The diamond promises to be radiation hard well beyond particle fluences that can be tolerated by Si sensors. Recent results from the RD 42 collaboration on charge collection distance and on radiation hardness of CVD diamond samples will be reported. Measurements with diamond tracking devices, both strip detectors and pixel detectors, will be discussed. Results from beam tests using a diamond strip detector which was read out with fast, 25 ns shaping time, radiation-hard pipeline electronics will be presented.

  13. Availability of solar radiation and standards for solar access

    Energy Technology Data Exchange (ETDEWEB)

    Casabianca, G.A.; Evans, J.M. [Research Centre Habitat and Energy, Facultad de Arquitectura, Diseno y Urbanismo, Universidad de Buenos Aires, Capital Federal (Argentina)

    1997-12-31

    In southern Argentina, a region between latitudes 38 deg C and 55 deg C S, the heating demand in the residential sector is high while the availability of solar radiation is limited. A new proposal for solar access standards has been developed, taking into account the climatic conditions of each location, the effective availability of solar radiation and the direct sunlight requirements. This study analyses the climatic conditions for the Patagonia, relating heating demand and solar radiation availability in different sites, and presents the development of new sunlight standards that respond to these regional conditions. As a result of this study, the new Argentine standard TRAM 11.603 includes new conditions to protect solar access and provide design recommendations. (orig.) 4 refs.

  14. Radiation resistant passivation of silicon solar cells

    International Nuclear Information System (INIS)

    Swanson, R.M.; Gan, J.Y.; Gruenbaum, P.E.

    1991-01-01

    This patent describes a silicon solar cell having improved stability when exposed to concentrated solar radiation. It comprises a body of silicon material having a major surface for receiving radiation, a plurality of p and n conductivity regions in the body for collecting electrons and holes created by impinging radiation, and a passivation layer on the major surface including a first layer of silicon oxide in contact with the body and a polycrystalline silicon layer on the first layer of silicon oxide

  15. Measurement of global solar radiation over Brunei Darussalam

    International Nuclear Information System (INIS)

    Malik, A.Q.; Ak Abd Malik Abd Raub Pg Ghani

    2006-01-01

    Measurements of global solar radiation on a horizontal surface were carried out for a period of 11 months starting from June 2001 to April 2002. The pyrano meter (Kipp and Zonen) was placed at the top of the library building of University of Brunei Darussalam, which affords optimum exposure to the instrument sensor without appreciable obstacle for incoming global radiation. The maximum and minimum monthly-averaged global irradiations of 553 W/m 2 and 433 W/m 2 were recorded for the months of March and October respectively. The variation of global solar radiation can be divided into two distinct groups - the low radiation values being associated with cloud and turbidity while the high values are associated with less turbid and cloudy periods

  16. Predicted solar cell edge radiation effects

    International Nuclear Information System (INIS)

    Gates, M.T.

    1993-01-01

    The Advanced Solar Cell Orbital Test (ASCOT) will test six types of solar cells in a high energy proton environment. During the design of the experiment a question was raised about the effects of proton radiation incident on the edge of the solar cells and whether edge radiation shielding was required. Historical geosynchronous data indicated that edge radiation damage is not detectable over the normal end of life solar cell degradation; however because the ASCOT radiation environment has a much higher and more energetic fluence of protons, considerably more edge damage is expected. A computer analysis of the problem was made by modeling the expected radiation damage at the cell edge and using a network model of small interconnected solar cells to predict degradation in the cell's electrical output. The model indicated that the deepest penetration of edge radiation was at the top of the cell near the junction where the protons have access to the cell through the low density cell/cover adhesive layer. The network model indicated that the cells could tolerate high fluences at their edge as long as there was high electrical resistance between the edge radiated region and the contact system on top of the cell. The predicted edge radiation related loss was less than 2% of maximum power for GaAs/Ge solar cells. As a result, no edge radiation protection was used for ASCOT

  17. Distributed solar radiation fast dynamic measurement for PV cells

    Science.gov (United States)

    Wan, Xuefen; Yang, Yi; Cui, Jian; Du, Xingjing; Zheng, Tao; Sardar, Muhammad Sohail

    2017-10-01

    need of complex local installations, configuring of our SRMA system is very easy. Lora also provides SRMA a means to overcome the short communication distance and weather signal propagation decline such as in ZigBee and WiFi. The host computer in SRMA system uses the low power single-board PC EMB-3870 which was produced by NORCO. Wind direction sensor SM5386B and wind-force sensor SM5387B are installed to host computer through RS-485 bus for wind reference data collection. And Davis 6450 solar radiation sensor, which is a precision instrument that detects radiation at wavelengths of 300 to 1100 nanometers, allow host computer to follow real-time solar radiation. A LoRa polling scheme is adopt for the communication between host computer and terminal nodes in SRMA. An experimental SRMA has been established. This system was tested in Ganyu, Jiangshu province from May to August, 2016. In the test, the distances between the nodes and the host computer were between 100m and 1900m. At work, SRMA system showed higher reliability. Terminal nodes could follow the instructions from host computer and collect solar radiation data of distributed PV cells effectively. And the host computer managed the SRAM and achieves reference parameters well. Communications between the host computer and terminal nodes were almost unaffected by the weather. In conclusion, the testing results show that SRMA could be a capable method for fast dynamic measuring about solar radiation and related PV cell operating characteristics.

  18. Solar radiation on Mars: Update 1991

    Science.gov (United States)

    Appelbaum, Joseph; Landis, Geoffrey A.

    1991-01-01

    Detailed information on solar radiation characteristics on Mars are necessary for effective design of future planned solar energy systems operating on the surface of Mars. A procedure and solar radiation related data are presented from which the daily variation of the global, direct beam and diffuse insolation on Mars are calculated. Given the optical depth of the Mars atmosphere, the global radiation is calculated from the normalized net flux function based on multiple wavelength and multiple scattering of the solar radiation. The direct beam was derived from the optical depth using Beer's law, and the diffuse component was obtained from the difference of the global and the direct beam radiation. The optical depths of the Mars atmosphere were derived from images taken of the Sun with a special diode on the cameras used on the two Viking Landers.

  19. Acoustic emission sensor radiation damage threshold experiment

    International Nuclear Information System (INIS)

    Beeson, K.M.; Pepper, C.E.

    1994-01-01

    Determination of the threshold for damage to acoustic emission sensors exposed to radiation is important in their application to leak detection in radioactive waste transport and storage. Proper response to system leaks is necessary to ensure the safe operation of these systems. A radiation impaired sensor could provide ''false negative or false positive'' indication of acoustic signals from leaks within the system. Research was carried out in the Radiochemical Technology Division at Oak Ridge National Laboratory to determine the beta/gamma radiation damage threshold for acoustic emission sensor systems. The individual system consisted of an acoustic sensor mounted with a two part epoxy onto a stainless steel waveguide. The systems were placed in an irradiation fixture and exposed to a Cobalt-60 source. After each irradiation, the sensors were recalibrated by Physical Acoustics Corporation. The results were compared to the initial calibrations performed prior to irradiation and a control group, not exposed to radiation, was used to validate the results. This experiment determines the radiation damage threshold of each acoustic sensor system and verifies its life expectancy, usefulness and reliability for many applications in radioactive environments

  20. Flexible wearable sensor nodes with solar energy harvesting.

    Science.gov (United States)

    Taiyang Wu; Arefin, Md Shamsul; Redoute, Jean-Michel; Yuce, Mehmet Rasit

    2017-07-01

    Wearable sensor nodes have gained a lot of attention during the past few years as they can monitor and record people's physical parameters in real time. Wearable sensor nodes can promote healthy lifestyles and prevent the occurrence of potential illness or injuries. This paper presents a flexible wearable sensor system powered by an efficient solar energy harvesting technique. It can measure the subject's heartbeats using a photoplethysmography (PPG) sensor and perform activity monitoring using an accelerometer. The solar energy harvester adopts an output current based maximum power point tracking (MPPT) algorithm, which controls the solar panel to operate within its high output power range. The power consumption of the flexible sensor nodes has been investigated under different operation conditions. Experimental results demonstrate that wearable sensor nodes can work for more than 12 hours when they are powered by the solar energy harvester for 3 hours in the bright sunlight.

  1. Image dissector photocathode solar damage test program. [solar radiation shielding using a fast optical lens

    Science.gov (United States)

    Smith, R. A.

    1977-01-01

    Image dissector sensors of the same type which will be used in the NASA shuttle star tracker were used in a series of tests directed towards obtaining solar radiation/time damage criteria. Data were evaluated to determine the predicted level of operability of the star tracker if tube damage became a reality. During the test series a technique for reducing the solar damage effect was conceived and verified. The damage concepts are outlined and the test methods and data obtained which were used for verification of the technique's feasibility are presented. The ability to operate an image dissector sensor with the solar image focussed on the photocathode by a fast optical lens under certain conditions is feasible and the elimination of a mechanical protection device is possible.

  2. High Radiation Resistance IMM Solar Cell

    Science.gov (United States)

    Pan, Noren

    2015-01-01

    Due to high launch costs, weight reduction is a key driver for the development of new solar cell technologies suitable for space applications. This project is developing a unique triple-junction inverted metamorphic multijunction (IMM) technology that enables the manufacture of very lightweight, low-cost InGaAsP-based multijunction solar cells. This IMM technology consists of indium (In) and phosphorous (P) solar cell active materials, which are designed to improve the radiation-resistant properties of the triple-junction solar cell while maintaining high efficiency. The intrinsic radiation hardness of InP materials makes them of great interest for building solar cells suitable for deployment in harsh radiation environments, such as medium Earth orbit and missions to the outer planets. NASA Glenn's recently developed epitaxial lift-off (ELO) process also will be applied to this new structure, which will enable the fabrication of the IMM structure without the substrate.

  3. Study of solar radiation prediction and modeling of relationships between solar radiation and meteorological variables

    International Nuclear Information System (INIS)

    Sun, Huaiwei; Zhao, Na; Zeng, Xiaofan; Yan, Dong

    2015-01-01

    Highlights: • We investigate relationships between solar radiation and meteorological variables. • A strong relationship exists between solar radiation and sunshine duration. • Daily global radiation can be estimated accurately with ARMAX–GARCH models. • MGARCH model was applied to investigate time-varying relationships. - Abstract: The traditional approaches that employ the correlations between solar radiation and other measured meteorological variables are commonly utilized in studies. It is important to investigate the time-varying relationships between meteorological variables and solar radiation to determine which variables have the strongest correlations with solar radiation. In this study, the nonlinear autoregressive moving average with exogenous variable–generalized autoregressive conditional heteroscedasticity (ARMAX–GARCH) and multivariate GARCH (MGARCH) time-series approaches were applied to investigate the associations between solar radiation and several meteorological variables. For these investigations, the long-term daily global solar radiation series measured at three stations from January 1, 2004 until December 31, 2007 were used in this study. Stronger relationships were observed to exist between global solar radiation and sunshine duration than between solar radiation and temperature difference. The results show that 82–88% of the temporal variations of the global solar radiation were captured by the sunshine-duration-based ARMAX–GARCH models and 55–68% of daily variations were captured by the temperature-difference-based ARMAX–GARCH models. The advantages of the ARMAX–GARCH models were also confirmed by comparison of Auto-Regressive and Moving Average (ARMA) and neutral network (ANN) models in the estimation of daily global solar radiation. The strong heteroscedastic persistency of the global solar radiation series was revealed by the AutoRegressive Conditional Heteroscedasticity (ARCH) and Generalized Auto

  4. Solar radiation alert system : final report.

    Science.gov (United States)

    2009-03-01

    The Solar Radiation Alert (SRA) system continuously evaluates measurements of high-energy protons made by instruments on GOES satellites. If the measurements indicate a substantial elevation of effective dose rates at aircraft flight altitudes, the C...

  5. Effects of solar radiation on glass

    Science.gov (United States)

    Tucker, Dennis S.; Kinser, Donald L.

    1991-01-01

    The effects of solar radiation of selected glasses are reported. Optical property degradation is studied using UV-Vis spectrophotometry. Strength changes are measured using a concentric ring bend test. Direct fracture toughness measurements using an indentation test are planned.

  6. The National Solar Radiation Database (NSRDB)

    Energy Technology Data Exchange (ETDEWEB)

    Sengupta, Manajit; Habte, Aron; Lopez, Anthony; Xie, Yu; Molling, Christine; Gueymard, Christian

    2017-03-13

    This presentation provides a high-level overview of the National Solar Radiation Database (NSRDB), including sensing, measurement and forecasting, and discusses observations that are needed for research and product development.

  7. The influence of the solar radiation model on the calcutated solar radiation from a horizontal surface to a tilted surface

    DEFF Research Database (Denmark)

    Andersen, Elsa; Lund, Hans; Furbo, Simon

    2004-01-01

    Measured solar radiation data are most commonly available as total solar radiation on a horizontal surface. When using solar radiation measured on horizontal to calculate the solar radiation on tilted surfaces and thereby the thermal performance of different applications such as buildings and solar...... heating systems, different solar radiation models can be used. The calculation of beam radiation from a horizontal surface to a tilted surface can be done exactly whereas different solar radiation models can calculate the sky diffuse radiation. The sky diffuse radiation can either be assumed evenly...... in the calculation. The weather data are measured at the solar radiation measurement station, SMS at the Department of Civil Engineering at the Technical University of Denmark. In this study the weather data are combined with solar collector calculations based on solar collector test carried out at Solar Energy...

  8. Detecting drift bias and exposure errors in solar and photosynthetically active radiation data

    Science.gov (United States)

    All-black thermopile pyranometers are commonly used to measure solar radiation. Ensuring that the sensors are stable and free of drift is critical to accurately measure small variations in global solar irradiance (K'), which is a potential driver of changes in surface temperature. We demonstrate tha...

  9. Solar Radiation and Climate Experiment (SORCE) Satellite

    Science.gov (United States)

    2003-01-01

    This is a close-up of the NASA-sponsored Solar Radiation and Climate Experiment (SORCE) Satellite. The SORCE mission, launched aboard a Pegasus rocket January 25, 2003, will provide state of the art measurements of incoming x-ray, ultraviolet, visible, near-infrared, and total solar radiation. Critical to studies of the Sun and its effect on our Earth system and mankind, SORCE will provide measurements that specifically address long-term climate change, natural variability and enhanced climate prediction, and atmospheric ozone and UV-B radiation. Orbiting around the Earth accumulating solar data, SORCE measures the Sun's output with the use of state-of-the-art radiometers, spectrometers, photodiodes, detectors, and bolo meters engineered into instruments mounted on a satellite observatory. SORCE is carrying 4 instruments: The Total Irradiance Monitor (TIM); the Solar Stellar Irradiance Comparison Experiment (SOLSTICE); the Spectral Irradiance Monitor (SIM); and the XUV Photometer System (XPS).

  10. Solar radiation at Parsons, West Virginia

    Science.gov (United States)

    James H. Patric; Stanley Caruso

    1978-01-01

    Twelve years of solar radiation data, measured with a Kipp-Zonen pyranometer, were recorded near Parsons, West Virginia. The data agree well with calculated values of potential and average radiation for the vicinity and are applicable to the central Appalachian region.

  11. A Model for Hourly Solar Radiation Data Generation from Daily Solar Radiation Data Using a Generalized Regression Artificial Neural Network

    OpenAIRE

    Khatib, Tamer; Elmenreich, Wilfried

    2015-01-01

    This paper presents a model for predicting hourly solar radiation data using daily solar radiation averages. The proposed model is a generalized regression artificial neural network. This model has three inputs, namely, mean daily solar radiation, hour angle, and sunset hour angle. The output layer has one node which is mean hourly solar radiation. The training and development of the proposed model are done using MATLAB and 43800 records of hourly global solar radiation. The results show that...

  12. Solar radiation estimation based on the insolation

    International Nuclear Information System (INIS)

    Assis, F.N. de; Steinmetz, S.; Martins, S.R.; Mendez, M.E.G.

    1998-01-01

    A series of daily global solar radiation data measured by an Eppley pyranometer was used to test PEREIRA and VILLA NOVA’s (1997) model to estimate the potential of radiation based on the instantaneous values measured at solar noon. The model also allows to estimate the parameters of PRESCOTT’s equation (1940) assuming a = 0,29 cosj. The results demonstrated the model’s validity for the studied conditions. Simultaneously, the hypothesis of generalizing the use of the radiation estimative formulas based on insolation, and using K = Ko (0,29 cosj + 0,50 n/N), was analysed and confirmed [pt

  13. Orbiter radiator panel solar focusing test

    Science.gov (United States)

    Howell, H. R.; Rankin, J. G.

    1983-01-01

    Test data are presented which define the area around the Orbiter radiator panels for which the solar reflections are concentrated to one-sun or more. The concave shape of the panels and their specular silver/Teflon coating causes focusing of the reflected solar energy which could have adverse heating effects on equipment or astronaut extravehicular activity (EVA) in the vicinity of the radiator panels. A room ambient test method was utilized with a one-tenth scale model of the radiator panels.

  14. Estimating hourly direct and diffuse solar radiation for the compilation of solar radiation distribution maps

    International Nuclear Information System (INIS)

    Ueyama, H.

    2005-01-01

    This paper presents a new method for estimating hourly direct and diffuse solar radiation. The essence of the method is the estimation of two important factors related to solar radiation, atmospheric transmittance and a dimensionless parameter, using empirical and physical equations and data from general meteorological observation stations. An equation for atmospheric transmittance of direct solar radiation and a dimensionless parameter representing diffuse solar radiation are developed. The equation is based on multiple regression analysis and uses three parameters as explanatory variates: calculated hourly extraterrestrial solar radiation on a horizontal plane, observed hourly sunshine duration and hourly precipitation as observed at a local meteorological observatory. The dimensionless parameter for estimating a diffuse solar radiation is then determined by linear least squares using observed hourly solar radiation at a local meteorological observatory. The estimated root mean square error (RMSE) of hourly direct and diffuse solar radiation is about 0.0-0.2 MJ¥m(-2)¥h(-1) in each mean period. The RMSE of the ten-day and monthly means of these quantities is about 0.0-0.2 MJ¥m(-2)¥h(-1), based on comparisons with AMeDAS station data, located at a distance of 6 km

  15. A Solar Position Sensor Based on Image Vision.

    Science.gov (United States)

    Ruelas, Adolfo; Velázquez, Nicolás; Villa-Angulo, Carlos; Acuña, Alexis; Rosales, Pedro; Suastegui, José

    2017-07-29

    Solar collector technologies operate with better performance when the Sun beam direction is normal to the capturing surface, and for that to happen despite the relative movement of the Sun, solar tracking systems are used, therefore, there are rules and standards that need minimum accuracy for these tracking systems to be used in solar collectors' evaluation. Obtaining accuracy is not an easy job, hence in this document the design, construction and characterization of a sensor based on a visual system that finds the relative azimuth error and height of the solar surface of interest, is presented. With these characteristics, the sensor can be used as a reference in control systems and their evaluation. The proposed sensor is based on a microcontroller with a real-time clock, inertial measurement sensors, geolocation and a vision sensor, that obtains the angle of incidence from the sunrays' direction as well as the tilt and sensor position. The sensor's characterization proved how a measurement of a focus error or a Sun position can be made, with an accuracy of 0.0426° and an uncertainty of 0.986%, which can be modified to reach an accuracy under 0.01°. The validation of this sensor was determined showing the focus error on one of the best commercial solar tracking systems, a Kipp & Zonen SOLYS 2. To conclude, the solar tracking sensor based on a vision system meets the Sun detection requirements and components that meet the accuracy conditions to be used in solar tracking systems and their evaluation or, as a tracking and orientation tool, on photovoltaic installations and solar collectors.

  16. Solar Radiation effect on the bituminous binder

    International Nuclear Information System (INIS)

    Tadeo Rico, A.; Torres Perez, A.

    2010-01-01

    Asphalt, used as binder in road construction, becomes more brittle and harder during working life on the surface of the road pavement, conducting toward their deterioration. This is caused by the oxidation of the molecular functional groups of the asphalt molecular structure. Moreover, it is observed that ultraviolet radiation increases the oxidation process. However, the effect of solar light on the asphalt degradation has been poorly researched. The aim of this work is to study asphalt ageing caused by effect of solar radiation, by using standard test. Four commercial asphalts from different companies were selected: two with penetration number 50/70, and the other two polymer modified asphalts. From each of the asphalts forty samples were taken off and placed in four different aging conditions of temperature and radiation for a period ranging from 40 to 500 days. Ring and Ball test, and Fraass breaking Point test, were used to analyse the changes of asphalt properties after exposition to solar radiation. The results of the four analyzed asphalts showed a distinct behaviour; not only in the test temperature increase but also in the rate. Another experiment was carried out. Samples from a hot mix asphalt batch were placed under solar radiation, and were compacted by the Marshall procedure after increasing periods of time. Density and resistance to plastic flow using Marshall Apparatus were measured. Results showed an increase in the stability of samples under radiation. Both experiments show that the solar radiation is enough to cause changes in the asphalt molecular structure due to oxidation. So that, the study of the effect of the solar radiation on the asphalt properties could be a good tool to asses the performances of asphalt pavement. (Author) 26 refs.

  17. Models for prediction of global solar radiation on horizontal surface ...

    African Journals Online (AJOL)

    The estimation of global solar radiation continues to play a fundamental role in solar engineering systems and applications. This paper compares various models for estimating the average monthly global solar radiation on horizontal surface for Akure, Nigeria, using solar radiation and sunshine duration data covering years ...

  18. Applicability of Daily Solar Radiation Estimated by Mountain Microclimate Simulation Model (MT-CLIM) in Korea

    International Nuclear Information System (INIS)

    Shim, K.M.; Kim, Y.S.; Lee, D.B.; Kang, K.K.; So, K.H.

    2012-01-01

    Accuracy of daily solar radiation estimated from a Mountain Microclimate Simulation Model (MT-CLIM) was assessed for seven observation sites with complex topography in Uiseong County. The coefficient of determination () between the observed and the estimated daily solar radiation was 0.52 for 7 sites for the study period from 1 August to 30 September 2009. Overall, the MT-CLIM overestimated the solar radiation with root mean square error (RMSE) of which is about 25% of the mean daily solar radiation () for the study period. Considering that the pyranometer's tolerance is of standard sensor, the RMSE of MT-CLIM was too large to accept for a direct application for agricultural sector. The reliability of solar radiation estimated by MT-CLIM must be improved by considering additional ways such as using a topography correction coefficient

  19. Radiation From Solar Activity | Radiation Protection | US EPA

    Science.gov (United States)

    2017-08-07

    Solar flares, coronal mass ejections (CMEs) and geomagnetic storms from the sun can send extreme bursts of ionizing radiation and magnetic energy toward Earth. Some of this energy is in the form ionizing radiation and some of the energy is magnetic energy.

  20. Obliquity Modulation of the Incoming Solar Radiation

    Science.gov (United States)

    Liu, Han-Shou; Smith, David E. (Technical Monitor)

    2001-01-01

    Based on a basic principle of orbital resonance, we have identified a huge deficit of solar radiation induced by the combined amplitude and frequency modulation of the Earth's obliquity as possibly the causal mechanism for ice age glaciation. Including this modulation effect on solar radiation, we have performed model simulations of climate change for the past 2 million years. Simulation results show that: (1) For the past 1 million years, temperature fluctuation cycles were dominated by a 100-Kyr period due to amplitude-frequency resonance effect of the obliquity; (2) From 2 to 1 million years ago, the amplitude-frequency interactions. of the obliquity were so weak that they were not able to stimulate a resonance effect on solar radiation; (3) Amplitude and frequency modulation analysis on solar radiation provides a series of resonance in the incoming solar radiation which may shift the glaciation cycles from 41-Kyr to 100-Kyr about 0.9 million years ago. These results are in good agreement with the marine and continental paleoclimate records. Thus, the proposed climate response to the combined amplitude and frequency modulation of the Earth's obliquity may be the key to understanding the glaciation puzzles in paleoclimatology.

  1. Radiation effects on active pixel sensors (APS)

    International Nuclear Information System (INIS)

    Cohen, M.; David, J.P.

    1999-01-01

    Active pixel sensor (APS) is a new generation of image sensors which presents several advantages relatively to charge coupled devices (CCDs) particularly for space applications (APS requires only 1 voltage to operate which reduces considerably current consumption). Irradiation was performed using 60 Co gamma radiation at room temperature and at a dose rate of 150 Gy(Si)/h. 2 types of APS have been tested: photodiode-APS and photoMOS-APS. The results show that photoMOS-APS is more sensitive to radiation effects than photodiode-APS. Important parameters of image sensors like dark currents increase sharply with dose levels. Nevertheless photodiode-APS sensitivity is one hundred time lower than photoMOS-APS sensitivity

  2. Solar Radiation Research Laboratory | Energy Systems Integration Facility |

    Science.gov (United States)

    Solar Radiation Research Laboratory (SRRL) has been collecting continuous measurements of basic solar continuous operation. More than 75 instruments contribute to the Baseline Measurement System by recording

  3. Energy parameter estimation in solar powered wireless sensor networks

    KAUST Repository

    Mousa, Mustafa

    2014-02-24

    The operation of solar powered wireless sensor networks is associated with numerous challenges. One of the main challenges is the high variability of solar power input and battery capacity, due to factors such as weather, humidity, dust and temperature. In this article, we propose a set of tools that can be implemented onboard high power wireless sensor networks to estimate the battery condition and capacity as well as solar power availability. These parameters are very important to optimize sensing and communications operations and maximize the reliability of the complete system. Experimental results show that the performance of typical Lithium Ion batteries severely degrades outdoors in a matter of weeks or months, and that the availability of solar energy in an urban solar powered wireless sensor network is highly variable, which underlines the need for such power and energy estimation algorithms.

  4. Energy parameter estimation in solar powered wireless sensor networks

    KAUST Repository

    Mousa, Mustafa; Claudel, Christian G.

    2014-01-01

    The operation of solar powered wireless sensor networks is associated with numerous challenges. One of the main challenges is the high variability of solar power input and battery capacity, due to factors such as weather, humidity, dust and temperature. In this article, we propose a set of tools that can be implemented onboard high power wireless sensor networks to estimate the battery condition and capacity as well as solar power availability. These parameters are very important to optimize sensing and communications operations and maximize the reliability of the complete system. Experimental results show that the performance of typical Lithium Ion batteries severely degrades outdoors in a matter of weeks or months, and that the availability of solar energy in an urban solar powered wireless sensor network is highly variable, which underlines the need for such power and energy estimation algorithms.

  5. Solar Radiation on Mars: Tracking Photovoltaic Array

    Science.gov (United States)

    Appelbaum, Joseph; Flood, Dennis J.; Crutchik, Marcos

    1994-01-01

    A photovoltaic power source for surface-based operation on Mars can offer many advantages. Detailed information on solar radiation characteristics on Mars and the insolation on various types of collector surfaces are necessary for effective design of future planned photovoltaic systems. In this article we have presented analytical expressions for solar radiation calculation and solar radiation data for single axis (of various types) and two axis tracking surfaces and compared the insulation to horizontal and inclined surfaces. For clear skies (low atmospheric dust load) tracking surfaces resulted in higher insolation than stationary surfaces, whereas for highly dusty atmospheres, the difference is small. The insolation on the different types of stationary and tracking surfaces depend on latitude, season and optical depth of the atmosphere, and the duration of system operation. These insolations have to be compared for each mission.

  6. Adaptive Control of the Packet Transmission Period with Solar Energy Harvesting Prediction in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Kideok Kwon

    2015-04-01

    Full Text Available A number of research works has studied packet scheduling policies in energy scavenging wireless sensor networks, based on the predicted amount of harvested energy. Most of them aim to achieve energy neutrality, which means that an embedded system can operate perpetually while meeting application requirements. Unlike other renewable energy sources, solar energy has the feature of distinct periodicity in the amount of harvested energy over a day. Using this feature, this paper proposes a packet transmission control policy that can enhance the network performance while keeping sensor nodes alive. Furthermore, this paper suggests a novel solar energy prediction method that exploits the relation between cloudiness and solar radiation. The experimental results and analyses show that the proposed packet transmission policy outperforms others in terms of the deadline miss rate and data throughput. Furthermore, the proposed solar energy prediction method can predict more accurately than others by 6.92%.

  7. Adaptive control of the packet transmission period with solar energy harvesting prediction in wireless sensor networks.

    Science.gov (United States)

    Kwon, Kideok; Yang, Jihoon; Yoo, Younghwan

    2015-04-24

    A number of research works has studied packet scheduling policies in energy scavenging wireless sensor networks, based on the predicted amount of harvested energy. Most of them aim to achieve energy neutrality, which means that an embedded system can operate perpetually while meeting application requirements. Unlike other renewable energy sources, solar energy has the feature of distinct periodicity in the amount of harvested energy over a day. Using this feature, this paper proposes a packet transmission control policy that can enhance the network performance while keeping sensor nodes alive. Furthermore, this paper suggests a novel solar energy prediction method that exploits the relation between cloudiness and solar radiation. The experimental results and analyses show that the proposed packet transmission policy outperforms others in terms of the deadline miss rate and data throughput. Furthermore, the proposed solar energy prediction method can predict more accurately than others by 6.92%.

  8. A solar radiation database for Chile.

    Science.gov (United States)

    Molina, Alejandra; Falvey, Mark; Rondanelli, Roberto

    2017-11-01

    Chile hosts some of the sunniest places on earth, which has led to a growing solar energy industry in recent years. However, the lack of high resolution measurements of solar irradiance becomes a critical obstacle for both financing and design of solar installations. Besides the Atacama Desert, Chile displays a large array of "solar climates" due to large latitude and altitude variations, and so provides a useful testbed for the development of solar irradiance maps. Here a new public database for surface solar irradiance over Chile is presented. This database includes hourly irradiance from 2004 to 2016 at 90 m horizontal resolution over continental Chile. Our results are based on global reanalysis data to force a radiative transfer model for clear sky solar irradiance and an empirical model based on geostationary satellite data for cloudy conditions. The results have been validated using 140 surface solar irradiance stations throughout the country. Model mean percentage error in hourly time series of global horizontal irradiance is only 0.73%, considering both clear and cloudy days. The simplicity and accuracy of the model over a wide range of solar conditions provides confidence that the model can be easily generalized to other regions of the world.

  9. Measurement of solar radiation at the Earth's surface

    Science.gov (United States)

    Bartman, F. L.

    1982-01-01

    The characteristics of solar energy arriving at the surface of the Earth are defined and the history of solar measurements in the United States presented. Radiation and meteorological measurements being made at solar energy meteorological research and training sites and calibration procedures used there are outlined. Data illustrating the annual variation in daily solar radiation at Ann Arbor, Michigan and the diurnal variation in radiation at Albuquerque, New Mexico are presented. Direct normal solar radiation received at Albuquerque is contrasted with that received at Maynard, Massachusetts. Average measured global radiation for a period of one year for four locations under clear skies, 50% cloud cover, and 100% cloud cover is given and compared with the solar radiation at the top of the atmosphere. The May distribution of mean daily direct solar radiation and mean daily global solar radiation over the United States is presented. The effects of turbidity on the direct and circumsolar radiation are shown.

  10. New Low Cost Structure for Dual Axis Mount Solar Tracking System Using Adaptive Solar Sensor

    DEFF Research Database (Denmark)

    Argeseanu, Alin; Ritchie, Ewen; Leban, Krisztina Monika

    2010-01-01

    A solar tracking system is designed to optimize the operation of solar energy receivers. The objective of this paper is proposing a new tracking system structure with two axis. The success strategy of this new project focuses on the economical analysis of solar energy. Therefore it is important...... to determine the most cost effective design, to consider the costs of production and maintenance, and operating. The proposed tracking system uses a new solar sensor position with an adaptive feature....

  11. SOLAR RADIATION MAPS FOR EIIDOPIA Tesfaye Bayou and ...

    African Journals Online (AJOL)

    day-1, thus signifying the solar power potential ... data are available only for few places due to the high cost of ... the mean daily global solar radiation for Ethiopia ... wind speed and precipitation. ..... Insolation on Tilted Surfaces, Solar Energy,.

  12. Radiation distribution sensor with optical fibers for high radiation fields

    International Nuclear Information System (INIS)

    Takada, Eiji; Kimura, Atsushi; Hosono, Yoneichi; Takahashi, Hiroyuki; Nakazawa, Masaharu

    1999-01-01

    Radiation distribution sensors with their feasibilities have been described in earlier works. However, due to large radiation induced transmission losses in optical fibers, especially in the visible wavelength region, it has been difficult to apply these techniques to high radiation fields. In this study, we proposed a new concept of optical fiber based radiation distribution measurements with near infrared (IR) emission. Near IR scintillators were attached to the ends of optical fibers, where the fibers were bundled and connected to an N-MOS line sensor or a cooled CCD camera. From the measurements of each area density, the radiation levels at the positions of the scintillators can be known. The linearity between the gamma dose rate at each scintillator and the registered counts has been examined. For correcting the radiation induced loss effects, we applied the Optical Time Domain Reflectometry technique to measure the loss distribution and from the results, a possibility for correction of the loss effect has been demonstrated. The applicable dose rate range was evaluated to be from 0.1 to 10 3 Gy/h. This system can be a promising tool as a flexible dose rate distribution monitor in radiation facilities like nuclear plants and accelerator facilities. (author)

  13. A solar charge and discharge controller for wireless sensor nodes

    Science.gov (United States)

    Dang, Yibo; Shen, Shu

    2018-02-01

    Aiming at the energy supply problem that restricts the life of wireless sensor nodes, a solar energy charge and discharge controller suitable for wireless sensor nodes is designed in this paper. A Microcontroller is used as the core of the solar charge and discharge controller. The software of the solar charge and discharge controller adopts the C language to realize the program of the main control module. Firstly, the function of monitoring solar panel voltage and lithium battery voltage are simulated by Protel software, and the charge time is tested in cloudy and overcast outdoor environment. The results of the experiment show that our controller meets the power supply demand of wireless sensor nodes.

  14. Solar and terrestrial radiation: methods and measurements

    National Research Council Canada - National Science Library

    Coulson, Kinsell L

    1975-01-01

    ... AND RETRIEVAL SYSTEM, WITHOUT PERMISSION IN WRITING FROM THE PUBLISHER. ACADEMIC PRESS, INC. Ill Fifth Avenue, New York, New York 10003 United Kingdom Edition published by A C A D E M I C PRESS, INC. (LONDON) LTD. 24/28 Oval Road, London NW1 Library of Congress Cataloging in Publication Data Coulson, Kinsell L Solar and terrestrial radiation. Inclu...

  15. Solar radiation observation stations updated to 1979

    Energy Technology Data Exchange (ETDEWEB)

    Carter, E.A.; Cristina, J.R.; Williams, B.B.

    1979-04-01

    The type of sensing and recording equipment for 420 stations in the US are listed alphabetically by states. The stations are divided according to whether or not they are in the basic National Weather Service, NOAA, network. Reports of summarized solar radiation data are listed in an appendix. (MHR)

  16. MODELING ACUTE EXPOSURE TO SOLAR RADIATION

    Science.gov (United States)

    One of the major technical challenges in calculating solar flux on the human form has been the complexity of the surface geometry (i.e., the surface normal vis a vis the incident radiation). The American Cancer Society reports that over 80% of skin cancers occur on the face, he...

  17. A wireless soil moisture sensor powered by solar energy.

    Directory of Open Access Journals (Sweden)

    Mingliang Jiang

    Full Text Available In a variety of agricultural activities, such as irrigation scheduling and nutrient management, soil water content is regarded as an essential parameter. Either power supply or long-distance cable is hardly available within field scale. For the necessity of monitoring soil water dynamics at field scale, this study presents a wireless soil moisture sensor based on the impedance transform of the frequency domain. The sensor system is powered by solar energy, and the data can be instantly transmitted by wireless communication. The sensor electrodes are embedded into the bottom of a supporting rod so that the sensor can measure soil water contents at different depths. An optimal design with time executing sequence is considered to reduce the energy consumption. The experimental results showed that the sensor is a promising tool for monitoring moisture in large-scale farmland using solar power and wireless communication.

  18. Solar cell radiation handbook. Addendum 1: 1982-1988

    International Nuclear Information System (INIS)

    Anspaugh, B.E.

    1989-02-01

    The Solar Cell Radiation Handbook (JPL Publication 82-69) is updated. In order to maintain currency of solar cell radiation data, recent solar cell designs have been acquired, irradiated with 1 MeV electrons, and measured. The results of these radiation experiments are reported

  19. Radiative origins of the solar corona

    International Nuclear Information System (INIS)

    Koch, P.

    1978-01-01

    Within observational accuracy, the radiation pressure aT 4 /3 at the effective solar temperature is equal to the coronal gas pressure nkT. This suggests a radiative gas discontinuity between optically thick and optically thin regions. Ideal transitions of this nature are studied and the applicability of this model to the Sun is explored. Further empirical corroboration is obtained if the gas pressure anomalies of Gulyaev are resolved by postulating a corrective gradient of radiation pressure possibly caused by Lyman-α opacity. (Auth.)

  20. Radiation balances and the solar constant

    Science.gov (United States)

    Crommelynck, D.

    1981-01-01

    The radiometric concepts are defined in order to consider various types of radiation balances and relate them to the diabetic form of the energy balance. Variability in space and time of the components of the radiation field are presented. A specific concept for sweeping which is tailored to the requirements is proposed. Finally, after establishing the truncated character of the present knowledge of the radiation balance. The results of the last observations of the solar constant are given. Ground and satellite measurement techniques are discussed.

  1. solaR: Solar Radiation and Photovoltaic Systems with R

    Directory of Open Access Journals (Sweden)

    Oscar Perpiñan Lamigueiro

    2012-08-01

    Full Text Available The solaR package allows for reproducible research both for photovoltaics (PV systems performance and solar radiation. It includes a set of classes, methods and functions to calculate the sun geometry and the solar radiation incident on a photovoltaic generator and to simulate the performance of several applications of the photovoltaic energy. This package performs the whole calculation procedure from both daily and intradaily global horizontal irradiation to the final productivity of grid-connected PV systems and water pumping PV systems.It is designed using a set of S4 classes whose core is a group of slots with multivariate time series. The classes share a variety of methods to access the information and several visualization methods. In addition, the package provides a tool for the visual statistical analysis of the performance of a large PV plant composed of several systems.Although solaR is primarily designed for time series associated to a location defined by its latitude/longitude values and the temperature and irradiation conditions, it can be easily combined with spatial packages for space-time analysis.

  2. Turning collectors for solar radiation

    Science.gov (United States)

    Barak, Amitzur Z.

    1976-01-01

    A device is provided for turning a solar collector about the polar axis so that the collector is directed toward the sun as the sun tracks the sky each day. It includes two heat-expansive elements and a shadow plate. In the morning a first expansive element is heated, expands to turn the collector to face the sun, while the second expansive element is shaded by the plate. In the afternoon the second element is heated, expands to turn the collector to face the sun, while the first is shaded by the plate.

  3. Conversion of solar radiation using parabolic mirrors

    Directory of Open Access Journals (Sweden)

    Jolanta Fieducik

    2017-08-01

    Full Text Available The use of solar energy is a promising source of renewable energy to cover the energy needs of our society. The aim of the study will be to analyze the possibility of converting solar energy using parabolic reflectors to the heat energy needed to meet the needs of hot water for a family of 4 people. This study presents simulations of the use of solar radiation using radiant concentration systems. The parabolic mirror directs the concentrated beam of sunlight onto a tube located in the focal plane, which is filled with water that under the influence of solar radiation heats up. This article assumes constant mirror geometry and tube cross section, while simulation is performed for different coefficients. For calculations it was assumed that the reflection coefficient of sunlight from the mirror r is variable and an analysis of its effect on the amount of heated liquid is made. The radiation absorption coefficient across the tube surface was determined by a, the thermal surface emissivity coefficient was determined as e and the simulations were performed at variable values for the amount of heated liquid. The calculations and their analysis show that, with appropriately chosen coefficients, it is possible to meet the needs of a 4-person family in warm water using the proposed installation in Poland.

  4. Solar ultraviolet radiation from cancer induction to cancer prevention: solar ultraviolet radiation and cell biology.

    Science.gov (United States)

    Tuorkey, Muobarak J

    2015-09-01

    Although decades have elapsed, researchers still debate the benefits and hazards of solar ultraviolet radiation (UVR) exposure. On the one hand, humans derive most of their serum 25-hydroxycholecalciferol [25(OH)D3], which has potent anticancer activity, from solar UVB radiation. On the other hand, people are more aware of the risk of cancer incidence associated with harmful levels of solar UVR from daily sunlight exposure. Epidemiological data strongly implicate UV radiation exposure as a major cause of melanoma and other cancers, as UVR promotes mutations in oncogenes and tumor-suppressor genes. This review highlights the impact of the different mutagenic effects of solar UVR, along with the cellular and carcinogenic challenges with respect to sun exposure.

  5. Tracking heat flux sensors for concentrating solar applications

    Science.gov (United States)

    Andraka, Charles E; Diver, Jr., Richard B

    2013-06-11

    Innovative tracking heat flux sensors located at or near the solar collector's focus for centering the concentrated image on a receiver assembly. With flux sensors mounted near a receiver's aperture, the flux gradient near the focus of a dish or trough collector can be used to precisely position the focused solar flux on the receiver. The heat flux sensors comprise two closely-coupled thermocouple junctions with opposing electrical polarity that are separated by a thermal resistor. This arrangement creates an electrical signal proportional to heat flux intensity, and largely independent of temperature. The sensors are thermally grounded to allow a temperature difference to develop across the thermal resistor, and are cooled by a heat sink to maintain an acceptable operating temperature.

  6. Temperature and Solar Radiation Effects on Photovoltaic Panel Power

    OpenAIRE

    Karafil, Akif; Ozbay, Harun; Kesler, Metin

    2016-01-01

    Solar energy is converted to electrical energy directly by semi-conductors materials used in Photovoltaic (PV) panels. Although, there has been great advancements in semi-conductor material technology in recent years panel efficiency is very lower. There are many factors affecting the panel efficiency such as tilt angle, shading, dust, solar radiation level, temperature and wiring losses. Among these factors, solar radiation level and temperature are more prominent. The solar radiation level ...

  7. Water purification using solar radiation in Nigeria

    International Nuclear Information System (INIS)

    Udounwa, A.E.; Osuji, R.U.

    2005-12-01

    In developing countries, lack of safe and reliable drinking water constitutes a major problem. Contaminated water is the major cause of most water borne diseases like diarrhoea. Disinfection of water is accomplished by a number of different physical - chemical treatments including boiling, application of chlorine and filtration techniques. Solar energy, which is universally available, can also be used effectively in this process, that is, to deactivate the micro-organisms present in this contaminated water thereby improving its microbiological quality. This treatment process is called solar water disinfection. This paper therefore appraises the extent to which research work has been done as regards purification of water using solar radiation in Nigeria vis-a-vis outside the country. It is hoped that it will serve as a wake-up-call for Nigerians especially those in remote areas with no treated pipe borne water supply. The problems and prospects of this technology as well as the policy implications are presented. (author)

  8. Effective polycrystalline sensor of ultraviolet radiation

    Directory of Open Access Journals (Sweden)

    S.Yu. Pavelets

    2017-10-01

    Full Text Available Deposition of special thin layers with high and low resistance in space charge region of surface barrier photoconverters based on the p-Cu1.8S/n-CdS structure leads to a sufficient increase in photosensitivity and decrease in dark tunneling-recombination current. Highly efficient and stable polycrystalline photoconverters of ultraviolet radiation based on polycrystalline CdS have been obtained. Electrical and photoelectric properties have been investigated, and the main operational parameters of ultraviolet sensors have been adduced. The reasons for high stability of the parameters inherent to the p-Cu1.8S/n-CdS sensors are as follows: the absence of impurity components additionally doped to the barrier structure and stability of the photocurrent photoemission component.

  9. Absorption of solar radiation in broken clouds

    Energy Technology Data Exchange (ETDEWEB)

    Zuev, V.E.; Titov, G.A.; Zhuravleva, T.B. [Institute of Atmospheric Optics, Tomsk (Russian Federation)

    1996-04-01

    It is recognized now that the plane-parallel model unsatisfactorily describes the transfer of radiation through broken clouds and that, consequently, the radiation codes of general circulation models (GCMs) must be refined. However, before any refinement in a GCM code is made, it is necessary to investigate the dependence of radiative characteristics on the effects caused by the random geometry of cloud fields. Such studies for mean fluxes of downwelling and upwelling solar radiation in the visible and near-infrared (IR) spectral range were performed by Zuev et al. In this work, we investigate the mean spectral and integrated absorption of solar radiation by broken clouds (in what follows, the term {open_quotes}mean{close_quotes} will be implied but not used, for convenience). To evaluate the potential effect of stochastic geometry, we will compare the absorption by cumulus (0.5 {le} {gamma} {le} 2) to that by equivalent stratus ({gamma} <<1) clouds; here {gamma} = H/D, H is the cloud layer thickness and D the characteristic horizontal cloud size. The equivalent stratus clouds differ from cumulus only in the aspect ratio {gamma}, all the other parameters coinciding.

  10. Electron Radiation Belts of the Solar System

    Science.gov (United States)

    Mauk, Barry; Fox, Nicola

    To address the question of what factors dictate similarities and differences between radiation belts, we present comparisons between the electron radiation belt spectra of all five strongly magnetized planets within the solar system: Earth, Jupiter, Saturn, Uranus, and Neptune. We choose the highest intensity observed electron spectrum within each system (highest specifically near 1 MeV) and compare them against expectations based on the so-called Kennel-Petschek limit (KP; 1966) for each system. For evaluating the KP limit, we begin with the new relativis-tically correct formulation of Summers et al. (2009) but then add several refinements of our own. Specifically, we: 1) utilized a much more flexible analytic spectral shape that allows us to accurately fit observed radiation belt spectra; 2) adopt the point of view that the anisotropy parameter is not a free parameter but must take on a minimal value, as originally proposed by Kennel and Petschek (1966); and 3) examine the differential characteristics of the KP limit along the lines of what Schulz and Davidson (1988) performed for the non-relativistic formula-tion. We find that three factors limit the highest electron radiation belt intensities within solar system planetary magnetospheres: a) whistler mode interactions that limit spectral intensities to a differential Kennel-Petschek limit (3 planets); b) the absence of robust acceleration pro-cesses associated with injection dynamics (1 planet); and c) material interactions between the radiation particles and clouds of gas and dust (1 planet).

  11. A Distributed Routing Scheme for Energy Management in Solar Powered Sensor Networks

    KAUST Repository

    Dehwah, Ahmad H.; Shamma, Jeff S.; Claudel, Christian G.

    2017-01-01

    Energy management is critical for solar-powered sensor networks. In this article, we consider data routing policies to optimize the energy in solar powered networks. Motivated by multipurpose sensor networks, the objective is to find the best

  12. Review of high bandwidth fiber optics radiation sensors

    International Nuclear Information System (INIS)

    Lyons, P.B.

    1985-01-01

    This paper summarizes the use of fiber optics or guided optical systems for radiation sensors. It is limited a passive systems wherein electrical is not required at the sensor location. However, electrically powered light sources, receivers and/or recorders may still be required for detection and data storage in sensor system operation. This paper emphasizes sensor technologies that permit high bandwidth measurements of transient radiation levels, and will also discuss several low bandwidth applications. 60 refs

  13. High mortality of Red Sea zooplankton under ambient solar radiation.

    Science.gov (United States)

    Al-Aidaroos, Ali M; El-Sherbiny, Mohsen M O; Satheesh, Sathianeson; Mantha, Gopikrishna; Agustī, Susana; Carreja, Beatriz; Duarte, Carlos M

    2014-01-01

    High solar radiation along with extreme transparency leads to high penetration of solar radiation in the Red Sea, potentially harmful to biota inhabiting the upper water column, including zooplankton. Here we show, based on experimental assessments of solar radiation dose-mortality curves on eight common taxa, the mortality of zooplankton in the oligotrophic waters of the Red Sea to increase steeply with ambient levels of solar radiation in the Red Sea. Responses curves linking solar radiation doses with zooplankton mortality were evaluated by exposing organisms, enclosed in quartz bottles, allowing all the wavelengths of solar radiation to penetrate, to five different levels of ambient solar radiation (100%, 21.6%, 7.2%, 3.2% and 0% of solar radiation). The maximum mortality rates under ambient solar radiation levels averaged (±standard error of the mean, SEM) 18.4±5.8% h(-1), five-fold greater than the average mortality in the dark for the eight taxa tested. The UV-B radiation required for mortality rates to reach ½ of maximum values averaged (±SEM) 12±5.6 h(-1)% of incident UVB radiation, equivalent to the UV-B dose at 19.2±2.7 m depth in open coastal Red Sea waters. These results confirm that Red Sea zooplankton are highly vulnerable to ambient solar radiation, as a consequence of the combination of high incident radiation and high water transparency allowing deep penetration of damaging UV-B radiation. These results provide evidence of the significance of ambient solar radiation levels as a stressor of marine zooplankton communities in tropical, oligotrophic waters. Because the oligotrophic ocean extends across 70% of the ocean surface, solar radiation can be a globally-significant stressor for the ocean ecosystem, by constraining zooplankton use of the upper levels of the water column and, therefore, the efficiency of food transfer up the food web in the oligotrophic ocean.

  14. High mortality of Red Sea zooplankton under ambient solar radiation.

    Directory of Open Access Journals (Sweden)

    Ali M Al-Aidaroos

    Full Text Available High solar radiation along with extreme transparency leads to high penetration of solar radiation in the Red Sea, potentially harmful to biota inhabiting the upper water column, including zooplankton. Here we show, based on experimental assessments of solar radiation dose-mortality curves on eight common taxa, the mortality of zooplankton in the oligotrophic waters of the Red Sea to increase steeply with ambient levels of solar radiation in the Red Sea. Responses curves linking solar radiation doses with zooplankton mortality were evaluated by exposing organisms, enclosed in quartz bottles, allowing all the wavelengths of solar radiation to penetrate, to five different levels of ambient solar radiation (100%, 21.6%, 7.2%, 3.2% and 0% of solar radiation. The maximum mortality rates under ambient solar radiation levels averaged (±standard error of the mean, SEM 18.4±5.8% h(-1, five-fold greater than the average mortality in the dark for the eight taxa tested. The UV-B radiation required for mortality rates to reach ½ of maximum values averaged (±SEM 12±5.6 h(-1% of incident UVB radiation, equivalent to the UV-B dose at 19.2±2.7 m depth in open coastal Red Sea waters. These results confirm that Red Sea zooplankton are highly vulnerable to ambient solar radiation, as a consequence of the combination of high incident radiation and high water transparency allowing deep penetration of damaging UV-B radiation. These results provide evidence of the significance of ambient solar radiation levels as a stressor of marine zooplankton communities in tropical, oligotrophic waters. Because the oligotrophic ocean extends across 70% of the ocean surface, solar radiation can be a globally-significant stressor for the ocean ecosystem, by constraining zooplankton use of the upper levels of the water column and, therefore, the efficiency of food transfer up the food web in the oligotrophic ocean.

  15. Real time sensor for therapeutic radiation delivery

    International Nuclear Information System (INIS)

    Bliss, M.; Craig, R.A.; Reeder, P.L.

    1998-01-01

    The invention is a real time sensor for therapeutic radiation. A probe is placed in or near the patient that senses in real time the dose at the location of the probe. The strength of the dose is determined by either an insertion or an exit probe. The location is determined by a series of vertical and horizontal sensing elements that gives the operator a real time read out dose location relative to placement of the patient. The increased accuracy prevents serious tissue damage to the patient by preventing overdose or delivery of a dose to a wrong location within the body. 14 figs

  16. Solar Radiation Pressure Binning for the Geosynchronous Orbit

    Science.gov (United States)

    Hejduk, M. D.; Ghrist, R. W.

    2011-01-01

    Orbital maintenance parameters for individual satellites or groups of satellites have traditionally been set by examining orbital parameters alone, such as through apogee and perigee height binning; this approach ignored the other factors that governed an individual satellite's susceptibility to non-conservative forces. In the atmospheric drag regime, this problem has been addressed by the introduction of the "energy dissipation rate," a quantity that represents the amount of energy being removed from the orbit; such an approach is able to consider both atmospheric density and satellite frontal area characteristics and thus serve as a mechanism for binning satellites of similar behavior. The geo-synchronous orbit (of broader definition than the geostationary orbit -- here taken to be from 1300 to 1800 minutes in orbital period) is not affected by drag; rather, its principal non-conservative force is that of solar radiation pressure -- the momentum imparted to the satellite by solar radiometric energy. While this perturbation is solved for as part of the orbit determination update, no binning or division scheme, analogous to the drag regime, has been developed for the geo-synchronous orbit. The present analysis has begun such an effort by examining the behavior of geosynchronous rocket bodies and non-stabilized payloads as a function of solar radiation pressure susceptibility. A preliminary examination of binning techniques used in the drag regime gives initial guidance regarding the criteria for useful bin divisions. Applying these criteria to the object type, solar radiation pressure, and resultant state vector accuracy for the analyzed dataset, a single division of "large" satellites into two bins for the purposes of setting related sensor tasking and orbit determination (OD) controls is suggested. When an accompanying analysis of high area-to-mass objects is complete, a full set of binning recommendations for the geosynchronous orbit will be available.

  17. Adaptive Multichannel Radiation Sensors for Plant Parameter Monitoring

    Science.gov (United States)

    Mollenhauer, Hannes; Remmler, Paul; Schuhmann, Gudrun; Lausch, Angela; Merbach, Ines; Assing, Martin; Mollenhauer, Olaf; Dietrich, Peter; Bumberger, Jan

    2016-04-01

    Nutrients such as nitrogen are playing a key role in the plant life cycle. They are much needed for chlorophyll production and other plant cell components. Therefore, the crop yield is strongly affected by plant nutrient status. Due to the spatial and temporal variability of soil characteristics or swaying agricultural inputs the plant development varies within a field. Thus, the determination of these fluctuations in the plant development is valuable for a detection of stress conditions and optimization of fertilisation due to its high environmental and economic impact. Plant parameters play crucial roles in plant growth estimation and prediction since they are used as indicators of plant performance. Especially indices derived out of remote sensing techniques provide quantitative information about agricultural crops instantaneously, and above all, non-destructively. Due to the specific absorption of certain plant pigments, a characteristic spectral signature can be seen in the visible and IR part of the electromagnetic spectrum, known as narrow-band peaks. In an analogous manner, the presence and concentration of different nutrients cause a characteristic spectral signature. To this end, an adequate remote sensing monitoring concept is needed, considering heterogeneity and dynamic of the plant population and economical aspects. This work will present the development and field investigations of an inexpensive multichannel radiation sensor to observe the incoming and reflected specific parts or rather distinct wavelengths of the solar light spectrum on the crop and facilitate the determination of different plant indices. Based on the selected sensor wavelengths, the sensing device allows the detection of specific parameters, e.g. plant vitality, chlorophyll content or nitrogen content. Besides the improvement of the sensor characteristic, the simple wavelength adaption, and the price-performance ratio, the achievement of appropriate energy efficiency as well as a

  18. Investigation of solar cell radiation damage

    International Nuclear Information System (INIS)

    Bernard, J.; Reulet, R.; Arndt, R.A.

    1974-01-01

    Development of communications satellites has led to the requirement for a greater and longer lived solar cell power source. Accordingly, studies have been undertaken with the aim of determining which solar cell array provides the greatest power at end of life and the amount of degradation. Investigation of the damage done to thin silicon and thin film CdS solar cells is being carried out in two steps. First, irradiations were performed singly with 0.15, 1.0 and 2.0MeV electrons and 0.7, 2.5 and 22MeV proton. Solar cells and their cover materials were irradiated separately in order to locate the sites of the damage. Diffusion length and I.V. characteristics of the cells and transmission properties of the cover materials were measured. All neasurements were made in vacuum immediately after irradiation. In the second part it is intended to study the effect of various combinations of proton, electron and photon irradiation both with and without an electrical load. The results of this part show whether synergism is involved in solar cell damage and the relative importance of each of three radiation sources if synergism is found [fr

  19. Fluctuation characteristics of solar radiation in crop cultivation

    International Nuclear Information System (INIS)

    Hayashi, S.; Suzuki, H.

    1996-01-01

    The objective of this study was to clarify the fluctuation of solar radiation for long and short periods, which is very crucial for plant growth. Data obtained from a meteorological observatory were used to investigate solar radiation and sunshine duration for a long period. For a short period, observation of global solar radiation and sky solar radiation were conducted in a glass house and at an open field. (1) Yearly average percentage of solar radiation at Kagawa from 1973 to 1994 was 44.3%, and its coefficient of variation was 3.9%. The percentage of possible sunshine and the coefficient were larger than those of solar radiation, 47.3% and 56% respectively. (2) Percentage of possible solar radiation and percentage of possible sunshine showed seasonal variation. Those coefficients of variation both increased exponentially with cloud amount. (3) Variations of global solar radiation and direct solar radiation were more remarkable in the glass house than those in the open field, while variations of sky solar radiation were small in the house and at the open field. (4) The fluctuation of solar radiation observed every 5 minutes was presented as the difference of radiation, present value minus the preceding value. The difference was positive in the morning, negative in the afternoon at the open field. In the house both positive and negative values were obtained the whole day. (5) Diurnal variation of ratio of direct solar radiation to sky solar radiation showed a parabolic effect, whereas it had irregular and large fluctuations at the open field

  20. Solar radiation data sources, applications, and network design

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-04-01

    A prerequisite to considering solar energy projects is to determine the requirements for information about solar radiation to apply to possible projects. This report offers techniques to help the reader specify requirements in terms of solar radiation data and information currently available, describes the past and present programs to record and present information to be used for most requirements, presents courses of action to help the user meet his needs for information, lists sources of solar radiation data and presents the problems, costs, benefits and responsibilities of programs to acquire additional solar radiation data. Extensive background information is provided about solar radiation data and its use. Specialized information about recording, collecting, processing, storing and disseminating solar radiation data is given. Several Appendices are included which provide reference material for special situations.

  1. Calibration of solar radiation measuring instruments. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bahm, R J; Nakos, J C

    1979-11-01

    A review of solar radiation measurement of instruments and some types of errors is given; and procedures for calibrating solar radiation measuring instruments are detailed. An appendix contains a description of various agencies who perform calibration of solar instruments and a description of the methods they used at the time this report was prepared. (WHK)

  2. Assessing the Performance of Global Solar Radiation Empirical ...

    African Journals Online (AJOL)

    In the region where solar radiation data are scarce, the next alternative method is to use solar radiation models to estimate the data needed for some applications such as simulation of crop performance and the design of solar energy conversion devices. In this paper, the validations of fifteen models for estimating monthly ...

  3. Spectral and electronic measurements of solar radiation

    International Nuclear Information System (INIS)

    Suzuki, Mamoru; Hanyu, Mitsuhiro

    1977-01-01

    The spectral data of solar radiation are necessary if detailed discussion is intended in relation to the utilization of solar energy. Since those data have not been fully prepared so far, a measuring equipment developed in Electro-technical Laboratory to obtain those data is described. The laboratory is now continuing the measurement at the wavelength of 0.3 μm to 1.1 μm. The equipment employs the system to always calibrate with the standard light source, it can measure both the direct light of the sun only and the sun light including sky light, and it enables to obtain the value based on the secondary standard of spectral illumination intensity established by the laboratory. The solar spectral irradiance is determined with the current readings of photomultiplier in the standard light source and the sun-light measurements at a wavelength and with the spectral illumination intensity from the standard light source. In order to practice such measurement many times at various wavelengths, control of the equipment, data collection, computation, drawing and listing are performed by a microcomputer. As an example, the data on Sept. 10, 1976, are shown comparing the graphs at three different hours. It can be well observed that the transmissivity attenuates with shorter wavelength, and the transmissivity in near infra-red region changes greatly due to the absorption of radiation by water vapour. (Wakatsuki, Y.)

  4. Solar Radiation Forecasting, Accounting for Daily Variability

    Directory of Open Access Journals (Sweden)

    Roberto Langella

    2016-03-01

    Full Text Available Radiation forecast accounting for daily and instantaneous variability was pursued by means of a new bi-parametric statistical model that builds on a model previously proposed by the same authors. The statistical model is developed with direct reference to the Liu-Jordan clear sky theoretical expression but is not bound by a specific clear sky model; it accounts separately for the mean daily variability and for the variation of solar irradiance during the day by means of two corrective parameters. This new proposal allows for a better understanding of the physical phenomena and improves the effectiveness of statistical characterization and subsequent simulation of the introduced parameters to generate a synthetic solar irradiance time series. Furthermore, the analysis of the experimental distributions of the two parameters’ data was developed, obtaining opportune fittings by means of parametric analytical distributions or mixtures of more than one distribution. Finally, the model was further improved toward the inclusion of weather prediction information in the solar irradiance forecasting stage, from the perspective of overcoming the limitations of purely statistical approaches and implementing a new tool in the frame of solar irradiance prediction accounting for weather predictions over different time horizons.

  5. Solar radiation in the Brazilian northeast

    Energy Technology Data Exchange (ETDEWEB)

    Tiba, Chigueru [Federal University of Pernambuco, Pernambuco (Brazil)

    2000-07-01

    The significant increase in recent years of the number of rural electrification systems (some thousands of them do exist) using photovoltaic technology installed in the Northeast of Brazil (1,500,000 km{sup 2}, approximately 42 million people) used for illumination or water pumping, calls for an improvement on the design procedures in order to reduce the burden of capital costs per unit of generated power. Such objective can be accomplished as long as a better knowledge about the solar resource is achieved, considering how much these applications depend on it. The sources of information on solar radiation in Brazil are quite varied at both institutional and publication level. At institutional Meteorology (INMET), State Departments of Agriculture, research institute, universities and electric power generation and distribution utilities. Progress reports or scientific and technical journals are the main publishing vehicles where this information can be found. This way, data quality varies considerably, showing, spatial and temporal discontinuities, in addition to the fact that measurement instruments and physical units of registered data are not standardized. The Solarimetric Atlas of Brazil was recently published and it contains that information, which is grouped, evaluated, qualified, and presented in a standardized way. It is one of the best currently existing sources of information, and in certainly consists of almost the entirety of the existing information on the solar resource (data on solar radiation and sunshine hours) in Brazil. By using this database, simultaneous records of solar radiation (measured with pyranoghaps or pyranometers) and sunshine hours with heliographs were obtained in 35 different places in the Northeast region. Coefficients a and b were calculated for those different places using Angstrom's correlation. Using the geostatistical interpolation method known as kriging, the values of a and b were placed on contour maps, the coverage of

  6. Modelling solar radiation interception in row plantation. 3. Application to a traditional vineyard

    International Nuclear Information System (INIS)

    Sinoquet, H.; Valancogne, C.; Lescure, A.; Bonhomme, R.

    1992-01-01

    Modeling solar radiation interception in row plantation. III. Application to a traditional vineyard. A previously described model of solar radiation interception was applied to a spatially discontinuous canopy: that of a traditional vineyard in which the classical terms of the radiative balance and the spatial distribution of the radiation transmitted to the soil were measured. Comparison of measured and simulated data gave satisfactory agreement for reflected radiation (fig 4), but major discrepancies appeared for mean transmitted radiation (fig 5). The use of small stationary sensors for measuring the transmitted radiation explains the latter observation, since most of the time they measured radiation received on the ground in the sunflecks or in the shaded area rather than mean radiation. This was verified by comparing the measured and simulated spatial distribution of transmitted radiation (figs 7, 8). Finally, the influence of the woody parts which were not taken into consideration in the model was clearly identified : it significantly reduced the transmission of incident radiation (fig 9), and to a greater degrees the closer the sensor was to the vegetation row [fr

  7. Temperature dependence of attitude sensor coalignments on the Solar Maximum Mission (SMM)

    Science.gov (United States)

    Pitone, D. S.; Eudell, A. H.; Patt, F. S.

    1990-01-01

    The temperature correlation of the relative coalignment between the fine-pointing sun sensor and fixed-head star trackers measured on the Solar Maximum Mission (SMM) is analyzed. An overview of the SMM, including mission history and configuration, is given. Possible causes of the misalignment variation are discussed, with focus placed on spacecraft bending due to solar-radiation pressure, electronic or mechanical changes in the sensors, uncertainty in the attitude solutions, and mounting-plate expansion and contraction due to thermal effects. Yaw misalignment variation from the temperature profile is assessed, and suggestions for spacecraft operations are presented, involving methods to incorporate flight measurements of the temperature-versus-alignment function and its variance in operational procedures and the spacecraft structure temperatures in the attitude telemetry record.

  8. Ultraviolet Radiation in the Solar System

    CERN Document Server

    Vázquez, M

    2006-01-01

    UV radiation is an important part in the electromagnetic spectrum since the energy of the photons is great enough to produce important chemical reactions in the atmospheres of planets and satellites of our Solar System, thereby affecting the transmission of this radiation to the ground and its physical properties. Scientists have used different techniques (balloons and rockets) to access to the information contained in this radiation, but the pioneering of this new frontier has not been free of dangers. The Sun is our main source of UV radiation and its description occupies the first two chapters of the book. The Earth is the only known location where life exists in a planetary system and therefore where the interaction of living organism with UV radiation can be tested through different epochs and on distinct species. The development of the human technology has affected the natural shield of ozone that protects complex lifeforms against damaging UV irradiation. The formation of the ozone hole and its consequ...

  9. Estimation of Solar Radiation using Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Slamet Suprayogi

    2004-01-01

    Full Text Available The solar radiation is the most important fator affeccting evapotranspiration, the mechanism of transporting the vapor from the water surface has also a great effect. The main objectives of this study were to investigate the potential of using Artificial Neural Network (ANN to predict solar radiation related to temperature. The three-layer backpropagation were developed, trained, and tested to forecast solar radiation for Ciriung sub Cachment. Result revealed that the ANN were able to well learn the events they were trained to recognize. Moreover, they were capable of effecctively generalize their training by predicting solar radiation for sets unseen cases.

  10. Multi-sensor radiation detector system

    International Nuclear Information System (INIS)

    Foster, R.G.; Cyboron, R.D.

    1975-01-01

    The invention is a multi-sensor radiation detection system including a self-powered detector and an ion or fission chamber, preferably joined as a unitary structure, for removable insertion into a nuclear reactor. The detector and chamber are connected electrically in parallel, requiring but two conductors extending out of the reactor to external electrical circuitry which includes a load impedance, a voltage source, and switch means. The switch means are employed to alternately connect the detector and chamber either with th load impedance or with the load impedance and the voltage source. In the former orientation, current through the load impedance indicates flux intensity at the self-powered detector and in the latter orientation, the current indicates flux intensity at the detector and fission chamber, though almost all of the current is contributed by the fission chamber. (auth)

  11. Comparison of Hourly Solar Radiation from a Ground–Based Station, Remote Sensing and Weather Forecast Models at a Coastal Site of South Italy (Lamezia Terme)

    DEFF Research Database (Denmark)

    Feudo, Teresa Lo; Avolio, Elenio; Gullì, Daniel

    2015-01-01

    The solar radiation is a critical input parameter when working with solar energy and radiation dependent surface processes. In this study, we present preliminary results from an inter-comparison between hourly values from a pyranometer, MSG-SEVIRI sensor and two meso-scale models, WRF and RAMS, i...

  12. Solar energy R + D programme, 1979-1983. Project F: solar radiation data

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    Individual presentations report work in the following areas: production of test reference years for model simulation of solar systems and components; global radiation atlas for horizontal surfaces; radiation data on inclined surfaces; intensity thresholds and cumulative frequency curves; useful energy output from solar collectors; network comparison of pyranometers; measurements of turbidity, spectral radiation, etc.; satellite data. (LEW)

  13. Simulation of solar radiative transfer in cumulus clouds

    Energy Technology Data Exchange (ETDEWEB)

    Zuev, V.E.; Titov, G.A. [Institute of Atmospheric Optics, Tomsk (Russian Federation)

    1996-04-01

    This work presents a 3-D model of radiative transfer which is used to study the relationship between the spatial distribution of cumulus clouds and fluxes (albedo and transmittance) of visible solar radiation.

  14. Climate variation based on temperature and solar radiation data ...

    African Journals Online (AJOL)

    ckaonga

    2015-03-12

    Mar 12, 2015 ... addition, the concentration of carbon dioxide over Malawi within the same period as temperature and solar radiation data ... plant diseases and pests which may have adverse effects ... object that absorbs and emits radiation).

  15. Measurement of solar energy radiation in Abu Dhabi, UAE

    International Nuclear Information System (INIS)

    Islam, M.D.; Kubo, I.; Ohadi, M.; Alili, A.A.

    2009-01-01

    This paper presents data on measurement of actual solar radiation in Abu Dhabi (24.43 deg. N, 54.45 deg. E). Global solar radiation and surface temperatures were measured and analyzed for one complete year. High resolution, real-time solar radiation and other meteorological data were collected and processed. Daily and monthly average solar radiation values were calculated from the one-minute average recorded values. The highest daily and monthly mean solar radiation values were 369 and 290 W/m 2 , respectively. The highest one-minute average daily solar radiation was 1041 W/m 2 . Yearly average daily energy input was 18.48 MJ/m 2 /day. Besides the global solar radiation, the daily and monthly average clearness indexes along with temperature variations are discussed. When possible, global solar energy radiation and some meteorological data are compared with corresponding data in other Arab state capitals. The data collected indicate that Abu Dhabi has a strong potential for solar energy capture

  16. Measurement of solar energy radiation in Abu Dhabi, UAE

    Energy Technology Data Exchange (ETDEWEB)

    Islam, M.D.; Kubo, I.; Ohadi, M.; Alili, A.A. [Department of Mechanical Engineering, The Petroleum Institute, Abu Dhabi, P.O. Box 2533 (United Arab Emirates)

    2009-04-15

    This paper presents data on measurement of actual solar radiation in Abu Dhabi (24.43 N, 54.45 E). Global solar radiation and surface temperatures were measured and analyzed for one complete year. High resolution, real-time solar radiation and other meteorological data were collected and processed. Daily and monthly average solar radiation values were calculated from the one-minute average recorded values. The highest daily and monthly mean solar radiation values were 369 and 290 W/m{sup 2}, respectively. The highest one-minute average daily solar radiation was 1041 W/m{sup 2}. Yearly average daily energy input was 18.48 MJ/m{sup 2}/day. Besides the global solar radiation, the daily and monthly average clearness indexes along with temperature variations are discussed. When possible, global solar energy radiation and some meteorological data are compared with corresponding data in other Arab state capitals. The data collected indicate that Abu Dhabi has a strong potential for solar energy capture. (author)

  17. Optimization of Stirling and Ericsson cycles by solar radiation

    Science.gov (United States)

    Badescu, V.

    This paper considers a model consisting of a source of radiation (the sun) and two energy converters. The first converter (the absorber) transforms the solar radiation into heat while the second one (which is a Stirling or Ericsson engine) uses heat to produce mechanical work. Polarization coefficients were introduced to characterize the radiation emitted by two components of the system (the sun and the first converter). The maximum conversion efficiency of solar radiation into work was studied.

  18. Simulation of Solar Radiation Incident on Horizontal and Inclined Surfaces

    Directory of Open Access Journals (Sweden)

    MA Basunia

    2012-12-01

    Full Text Available A computer model was developed to simulate the hourly, daily and monthly average of daily solar radiation on horizontal and inclined surfaces. The measured hourly and daily solar radiation was compared with simulated radiation, and favourable agreement was observed for the measured and predicted values on clear days. The measured and simulated monthly averages of total (diffuse and beam daily solar radiation were compared and a reasonable agreement was observed for a number of stations in Japan. The simulation showed that during the rice harvesting season, September to October, there is a daily average of 14.7 MJ/m2 of solar irradiation on a horizontal surface in Matsuyama, Japan. There is a similar amount of solar radiation on a horizontal surface during the major rice harvesting season, November to December, in Bangladesh. This radiation can be effectively utilized for drying rough rice and other farm crops.

  19. A rapid radiative transfer model for reflection of solar radiation

    Science.gov (United States)

    Xiang, X.; Smith, E. A.; Justus, C. G.

    1994-01-01

    A rapid analytical radiative transfer model for reflection of solar radiation in plane-parallel atmospheres is developed based on the Sobolev approach and the delta function transformation technique. A distinct advantage of this model over alternative two-stream solutions is that in addition to yielding the irradiance components, which turn out to be mathematically equivalent to the delta-Eddington approximation, the radiance field can also be expanded in a mathematically consistent fashion. Tests with the model against a more precise multistream discrete ordinate model over a wide range of input parameters demonstrate that the new approximate method typically produces average radiance differences of less than 5%, with worst average differences of approximately 10%-15%. By the same token, the computational speed of the new model is some tens to thousands times faster than that of the more precise model when its stream resolution is set to generate precise calculations.

  20. Solar radiation in the Baltic Sea

    Directory of Open Access Journals (Sweden)

    Jerzy Dera

    2010-12-01

    Full Text Available The influx of solar radiation to the Baltic Sea and its penetration into its waters is described on the basis of selected results of optical and bio-optical studies in the Baltic published by various authors during the past ca 50 years. The variability in the natural irradiance of this sea is illustrated on time scales from short-term fluctuations occurring during a single day to differences in mean monthly values over a period of many years. Data on variability of the proportions between UV, VIS and IR energy in the light reaching the sea surface are also discussed.Long-term monthly mean values of the incident solar radiation flux at the surface of the Baltic Proper are given; they were obtained from meteorological and solar radiation measurements and model approximations. The transmittances of these mean monthly radiation fluxes across the surface of the Baltic are given, as are the typical energyand spectral characteristics of the underwater irradiance, its attenuation with depth in the sea and the associated euphotic zone depths, as well as typical ranges of variability of these characteristics in different Baltic basins. Some of these characteristics are illustrated by typical empirical data. These mean values are not fully representative, however, because with the sole use of classical in situ measurement methods from on board research vessels in the Baltic, it has not been possible to gather a sufficientlyrepresentative set of empirical data that would adequately reflect the variability of the optical characteristics of all the basins of this sea. The article goes on to introduce the statistical model of vertical distributions of chlorophyll a concentration in the Baltic and the bio-optical model of Baltic Case 2 waters, the use of which contribute very significantly to this description of the optical characteristics and will enable this data set to be hugely expanded to include all the Baltic basins. This opportunity is presented by the

  1. Climatic zones of solar radiation of Galicia; Zonas climaticas de radiacion solar de Galicia

    Energy Technology Data Exchange (ETDEWEB)

    Vazquez, M.; Izquierdo, P.; Pose, M.; Prado, M. T.; Santos, J.

    2008-07-01

    The paper shows the results of a research on the solar radiation received in Galicia that allows assigning each one of the 315 Galician municipalities to one of the Climatic Zones of solar radiation, defined in the Spanish Building Technical Code (BTC). It is proposed to complete the assignment of climatic Zones in the BTC with a new zone, named Climatic Zone 0, with the objective to differentiate the geographical areas in Galicia with less than 3.4 kWh/m{sup 2}.day of yearly daily average solar radiation. The study is completed with the realization of a map of the Climate Zones of solar radiation of Galicia. (Author)

  2. Precise estimation of total solar radiation on tilted surface

    African Journals Online (AJOL)

    rajeev

    rarely available required for precise sizing of energy systems. The total solar radiation at different orientation and slope is needed to calculate the efficiency of the installed solar energy systems. To calculate clearness index (Kt) used by Gueymard (2000) for estimating solar irradiation H, irradiation at the earth's surface has ...

  3. An auto-calibration procedure for empirical solar radiation models

    NARCIS (Netherlands)

    Bojanowski, J.S.; Donatelli, Marcello; Skidmore, A.K.; Vrieling, A.

    2013-01-01

    Solar radiation data are an important input for estimating evapotranspiration and modelling crop growth. Direct measurement of solar radiation is now carried out in most European countries, but the network of measuring stations is too sparse for reliable interpolation of measured values. Instead of

  4. Resonance in the restricted problem caused by solar radiation pressure

    International Nuclear Information System (INIS)

    Bhatnagar, K.B.; Gupta, B.

    1977-01-01

    Resonance is discussed in the motion of an artificial Earth satellite caused by solar radiation pressure. The Hamiltonian and the generating functions occurring in the problem are expanded in the power series of small parameter β, which depends on solar radiation pressure. Also the perturbations in the osculating elements are obtained up to O(βsup(1/2)). (author)

  5. IMPACT OF SOLAR RADIATION CHANGE ON THE COLLECTOR EFFICIENTLY

    Directory of Open Access Journals (Sweden)

    Danuta Proszak-Miąsik

    2017-01-01

    Full Text Available In October 2014 in a building of Rzeszow University of Technology, a series of measurements was taken to calculate the parameters of a solar system with a flat collector, as installed on the roof of the building. The following parameters were obtained: the value of solar radiation intensity, the temperature of external air, the temperature on the collector, the temperature of water in the tank and the temperature of glycol on the supply and return lines. On the basis of the data received, charts were made to visually present how changes of solar radiation intensity affected parameters of the system. The study was conducted in autumn when the intensity of solar radiation decreases, compared with summer months. The publication aims to show that the solar system brings energy gains in periods of transition, and the instantaneous intensity of solar radiation are comparable to those in the summer.

  6. Attitude sensor alignment calibration for the solar maximum mission

    Science.gov (United States)

    Pitone, Daniel S.; Shuster, Malcolm D.

    1990-01-01

    An earlier heuristic study of the fine attitude sensors for the Solar Maximum Mission (SMM) revealed a temperature dependence of the alignment about the yaw axis of the pair of fixed-head star trackers relative to the fine pointing Sun sensor. Here, new sensor alignment algorithms which better quantify the dependence of the alignments on the temperature are developed and applied to the SMM data. Comparison with the results from the previous study reveals the limitations of the heuristic approach. In addition, some of the basic assumptions made in the prelaunch analysis of the alignments of the SMM are examined. The results of this work have important consequences for future missions with stringent attitude requirements and where misalignment variations due to variations in the temperature will be significant.

  7. ANALYSIS OF MEASURED AND MODELED SOLAR RADIATION AT THE TARS SOLAR HEATING PLANT IN DENMARK

    DEFF Research Database (Denmark)

    Tian, Zhiyong; Perers, Bengt; Furbo, Simon

    2017-01-01

    , such as solar radiation, inlet and outlet temperature for the solar collector field, flow rate and pressure, ambient temperature, Wind speed and wind direction were measured. Global horizontal radiation, direct normal irradiation (DNI) and total radiation on the tilted collector plane of the flat plate...... collector field have been measured in Tars solar heating plant. To determine the accuracy of modeled and measured solar radiation in Tars solar heating plant, monthly comparisons of measured and calculated radiation using 6 empirical models have been carried out. Comparisons of measured and modeled total......A novel combined solar heating plant with tracking parabolic trough collectors (PTC) and flat plate collectors (FPC) has been constructed and put into operation in Tars, 30 km north of Aalborg, Denmark in August 2015. To assess the operation performance of the plant, detailed parameters...

  8. Annual cycle of solar radiation in a deciduous forest

    International Nuclear Information System (INIS)

    Hutchison, B.A.; Matt, D.R.

    1977-01-01

    Periodic solar radiation measurements within and above an east Tennessee Liriodendron forest and continuous records of insolation from a nearby NOAA weather station were used to derive an approximation of the animal radiation regime within and above the deciduous forest. The interaction of changing solar elevations, insolation, and forest phenology are shown to control the radiation climate within the forest. Maximum radiation penetrates the forest in early spring as solar paths rise higher in the sky each day just prior to leaf expansion. After leaf expansion begins, average radiation received within the forest decreases rapidly despite continued increases in solar elevations and daily insolation. This forest attains full leaf in early June and from then until the advent of leaf abscission near the autumnal equinox, forest structure remains relatively static. Solar elevations and daily insolation decline following the summer solstice, however, and as a result, average radiation penetrating the forest slowly declines throughout the summer reaching an annual minimum in early autumn. With leaf fall, slightly increased amounts of radiation penetrate the forest but as within-forest solar paths continue to lengthen, radiation within the forest again declines. Minimum amounts of solar radiation penetrate the leafless forest around the winter solstice

  9. The National Solar Radiation Database (NSRDB): A Brief Overview

    Energy Technology Data Exchange (ETDEWEB)

    Habte, Aron M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sengupta, Manajit [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Lopez, Anthony [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-25

    This poster presents a high-level overview of the National Solar Radiation Database (NSRDB). The NSRDB uses the physics-based model (PSM), which was developed using: adapted PATMOS-X model for cloud identification and properties, REST-2 model for clear-sky conditions, and NREL's Fast All-sky Radiation Model for Solar Applications (FARMS) for cloudy-sky Global Horizontal Irradiance (GHI) solar irradiance calculations.

  10. Impact of climate change on occupational exposure to solar radiation.

    Science.gov (United States)

    Grandi, Carlo; Borra, Massimo; Militello, Andrea; Polichetti, Alessandro

    2016-01-01

    Occupational exposure to solar radiation may induce both acute and long-term effects on skin and eyes. Personal exposure is very difficult to assess accurately, as it depends on environmental, organisational and individual factors. The ongoing climate change interacting with stratospheric ozone dynamics may affect occupational exposure to solar radiation. In addition, tropospheric levels of environmental pollutants interacting with solar radiation may be altered by climate dynamics, so introducing another variable affecting the overall exposure to solar radiation. Given the uncertainties regarding the direction of changes in exposure to solar radiation due to climate change, compliance of outdoor workers with protective measures and a proper health surveillance are crucial. At the same time, education and training, along with the promotion of healthier lifestyles, are of paramount importance.

  11. Development of Software for Measurement and Analysis of Solar Radiation

    International Nuclear Information System (INIS)

    Mohamad Idris Taib; Abul Adli Anuar; Noor Ezati Shuib

    2015-01-01

    This software was under development using LabVIEW to be using with StellarNet spectrometers system with USB communication to computer. LabVIEW have capabilities in hardware interfacing, graphical user interfacing and mathematical calculation including array manipulation and processing. This software read data from StellarNet spectrometer in real-time and then processed for analysis. Several measurement of solar radiation and analysis have been done. Solar radiation involved mainly infra-red, visible light and ultra-violet. With solar radiation spectrum data, information of weather and suitability of plant can be gathered and analyzed. Furthermore, optimization of utilization and safety precaution of solar radiation can be planned. Using this software, more research and development in utilization and safety of solar radiation can be explored. (author)

  12. Correlation of total, diffuse, and direct solar radiation

    Science.gov (United States)

    Buyco, E. H.; Namkoong, D.

    1977-01-01

    Present requirements for realistic solar energy system evaluations necessitate a comprehensive body of solar-radition data. The data should include both diffuse and direct solar radiation as well as their total on an hourly (or shorter) basis. In general, however, only the total solar radiation values were recorded. This report presents a correlation that relates the diffuse component of an hourly total solar radiation value to the total radiation ratio of the maximum value attainable. The data used were taken at the Blue Hill Observatory in Milton, Massachusetts, for the period 1952. The relation - in the form of the data plots - can be used in situations in which only the hourly total radiation data are available but the diffuse component is desired.

  13. Evaluation of global solar radiation models for Shanghai, China

    International Nuclear Information System (INIS)

    Yao, Wanxiang; Li, Zhengrong; Wang, Yuyan; Jiang, Fujian; Hu, Lingzhou

    2014-01-01

    Highlights: • 108 existing models are compared and analyzed by 42 years meteorological data. • Fitting models based on measured data are established according to 42 years data. • All models are compared by recently 10 years meteorological data. • The results show that polynomial models are the most accurate models. - Abstract: In this paper, 89 existing monthly average daily global solar radiation models and 19 existing daily global solar radiation models are compared and analyzed by 42 years meteorological data. The results show that for existing monthly average daily global solar radiation models, linear models and polynomial models have been able to estimate global solar radiation accurately, and complex equation types cannot obviously improve the precision. Considering direct parameters such as latitude, altitude, solar altitude and sunshine duration can help improve the accuracy of the models, but indirect parameters cannot. For existing daily global solar radiation models, multi-parameter models are more accurate than single-parameter models, polynomial models are more accurate than linear models. Then measured data fitting monthly average daily global solar radiation models (MADGSR models) and daily global solar radiation models (DGSR models) are established according to 42 years meteorological data. Finally, existing models and fitting models based on measured data are comparative analysis by recent 10 years meteorological data, and the results show that polynomial models (MADGSR model 2, DGSR model 2 and Maduekwe model 2) are the most accurate models

  14. Test on radiation-withstanding properties of sensors

    International Nuclear Information System (INIS)

    Yagi, Hideyuki; Kakuta, Tsunemi; Ara, Katsuyuki

    1986-01-01

    In order to use for the remote operation system or in-line measuring system in the facilities handling radioactive substances, the development of the sensors having strengthened radiation-withstanding performance has been advanced. As a part of it, efforts have been exerted to phenomenologically grasp the radiation effect on various sensors and their materials, and to acquire the basic data. Irradiation test was carried out on solid image pick-up elements, optical parts eddy current sensors, pressure sensitive rubber, photo-electric proximity sensors and others, and the knowledge on their deterioration was obtained. Besides, the sensors and video-cameras having improved radiation-withstanding performance were made for trial, and the performance was tested. The interim report on these test results is made. By a series of the irradiation tests reported here, the basic data required for giving the guideline to the development of radiation withstanding sensors were able to be obtained. But in the present irradiation test, the number of specimens was too small to assure the radiation withstanding performance. In order to improve further the radiation withstanding performance of these sensors, it is necessary to carry out the irradiation test on such elements as condensers, diodes and ICs to accumulate the basic data. (Kako, I.)

  15. Fabrication of advanced military radiation detector sensor and performance evaluation

    International Nuclear Information System (INIS)

    Kang, Sin Yang

    2010-02-01

    Recently, our country is facing a continuous nuclear weapons threat. Therefore, we must have a high-level nuclear weapons protection system. The best protection against nuclear weapons is detecting their use to reduce casualties in our country to a minimum. That means, the development of a military radiation detector is a very important issue. The Korea army is using the 'PDR - 1K portable military radiation surveymeter' in NBC (Nuclear, Biological, Chemical warfare) operations. The PDR - 1K military detector can measure beta and gamma rays only but it cannot detect alpha particles. Because of its characteristics, the Korea army has weaknesses in tactical operations. The PDR - 1K sensor is based on a GM - tube sensor system. For the mechanical structure, detectors utilizing a GM-tube sensor do not work on a high - radiation battlefield and they do not carry out nuclide analysis for fixed electron signal output. In the meantime, the United States of America and Germany are using 'AN/PDR - 77' and 'SVG - 2' that were made from scintillator sensors. They have excellent physical qualities and radiation responses for military use. Also, nuclide analysis is available. Therefore, in this study we fabricated a military - grade scintillator radiation sensor that is able to detect alpha, beta, and gamma - rays to overcome PDR - 1K's weaknesses. Also, physical characteristics and radiation response evaluation for the fabricated sensors was carried out. The alpha - particle sensor and beta - ray sensor were fabricated using a ZnS(Ag) powder state scintillator, and a Saint - Gobain organic plastic scintillator BC-408 panel, respectively. The gamma ray sensor was manufactured using a 10 x 10 x 10 mm 3 CsI(Tl) inorganic scintillator crystal. A detailed explanation follows. The alpha particle sensor was fabricated by using air - brushing method to Zns(Ag) powder scintillator spreading. The ZnS(Ag) layer thickness was 35 μm (detection efficiency: 41%). This alpha - particle sensor

  16. Electromagnetic and nuclear radiation detector using micromechanical sensors

    Science.gov (United States)

    Thundat, Thomas G.; Warmack, Robert J.; Wachter, Eric A.

    2000-01-01

    Electromagnetic and nuclear radiation is detected by micromechanical sensors that can be coated with various interactive materials. As the micromechanical sensors absorb radiation, the sensors bend and/or undergo a shift in resonance characteristics. The bending and resonance changes are detected with high sensitivity by any of several detection methods including optical, capacitive, and piezoresistive methods. Wide bands of the electromagnetic spectrum can be imaged with picoJoule sensitivity, and specific absorptive coatings can be used for selective sensitivity in specific wavelength bands. Microcantilevers coated with optical cross-linking polymers are useful as integrating optical radiation dosimeters. Nuclear radiation dosimetry is possible by fabricating cantilevers from materials that are sensitive to various nuclear particles or radiation. Upon exposure to radiation, the cantilever bends due to stress and its resonance frequency shifts due to changes in elastic properties, based on cantilever shape and properties of the coating.

  17. The phase lag of temperature behind global solar radiation

    International Nuclear Information System (INIS)

    El Hussainy, F.M.

    1995-08-01

    This paper presented the relationship between the air temperature and the global solar radiation, which can be conveniently represented by the three characteristics: mean, amplitude and phase lag of the first harmonic of global radiation and air temperatures. A good correlation between the air temperature and the global solar radiation has been found when the phase lag between them is nearly of 30 days. (author). 4 refs, 9 figs, 1 tab

  18. Miniaturized, low power FGMOSFET radiation sensor and wireless dosimeter system

    KAUST Repository

    Arsalan, Muhammad

    2013-08-27

    A miniaturized floating gate (FG) MOSFET radiation sensor system is disclosed, The sensor preferably comprises a matched pair of sensor and reference FGMOSFETs wherein the sensor FGMOSFET has a larger area floating gate with an extension over a field oxide layer, for accumulation of charge and increased sensitivity. Elimination of a conventional control gate and injector gate reduces capacitance, and increases sensitivity, and allows for fabrication using standard low cost CMOS technology. A sensor system may be provided with integrated signal processing electronics, for monitoring a change in differential channel current I.sub.D, indicative of radiation dose, and an integrated negative bias generator for automatic pre-charging from a low voltage power source. Optionally, the system may be coupled to a wireless transmitter. A compact wireless sensor System on Package solution is presented, suitable for dosimetry for radiotherapy or other biomedical applications.

  19. Miniaturized, low power FGMOSFET radiation sensor and wireless dosimeter system

    KAUST Repository

    Arsalan, Muhammad; Shamim, Atif; Tarr, Nicholas Garry; Roy, Langis

    2013-01-01

    A miniaturized floating gate (FG) MOSFET radiation sensor system is disclosed, The sensor preferably comprises a matched pair of sensor and reference FGMOSFETs wherein the sensor FGMOSFET has a larger area floating gate with an extension over a field oxide layer, for accumulation of charge and increased sensitivity. Elimination of a conventional control gate and injector gate reduces capacitance, and increases sensitivity, and allows for fabrication using standard low cost CMOS technology. A sensor system may be provided with integrated signal processing electronics, for monitoring a change in differential channel current I.sub.D, indicative of radiation dose, and an integrated negative bias generator for automatic pre-charging from a low voltage power source. Optionally, the system may be coupled to a wireless transmitter. A compact wireless sensor System on Package solution is presented, suitable for dosimetry for radiotherapy or other biomedical applications.

  20. A model to calculate solar radiation fluxes on the Martian surface

    Directory of Open Access Journals (Sweden)

    Vicente-Retortillo Álvaro

    2015-01-01

    Full Text Available We present a new comprehensive radiative transfer model to study the solar irradiance that reaches the surface of Mars in the spectral range covered by MetSIS, a sensor aboard the Mars MetNet mission that will measure solar irradiance in several bands from the ultraviolet (UV to the near infrared (NIR. The model includes up-to-date wavelength-dependent radiative properties of dust, water ice clouds, and gas molecules. It enables the characterization of the radiative environment in different spectral regions under different scenarios. Comparisons between the model results and MetSIS observations will allow for the characterization of the temporal variability of atmospheric optical depth and dust size distribution, enhancing the scientific return of the mission. The radiative environment at the Martian surface has important implications for the habitability of Mars as well as a strong impact on its atmospheric dynamics and climate.

  1. Design and testing of an innovative solar radiation measurement device

    International Nuclear Information System (INIS)

    Badran, Omar; Al-Salaymeh, Ahmed; El-Tous, Yousif; Abdala, Wasfi

    2010-01-01

    After review of studies conducted on the solar radiation measuring systems, a new innovative instrument that would help in measuring the accurate solar radiation on horizontal surfaces has been designed and tested. An advanced instrument with ease of use and high precision that would enable the user to take the readings in terms of solar intensity (W/m 2 ) has been tested. Also, the innovative instrument can record instantaneous readings of the solar intensities as well as the averages value of the solar radiation flux during certain periods of time. The instrument based in its design on being programmed by programmable interfacing controller (PIC). Furthermore, the power supply circuit is fed by the solar energy cells and does not need an external power source.

  2. Observation of The Top of The Atmosphere Outgoing Longwave Radiation Using The Geostationary Earth Radiation Budget Sensor

    Science.gov (United States)

    Spencer, G.; Llewellyn-Jones, D.

    In the summer of 2002 the Meteosat Second Generation (MSG) satellite is due to be launched. On board the MSG satellite is the Geostationary Earth Radiation Budget (GERB) sensor. This is a new radiometer that will be able to observe and measure the outgoing longwave radiation from the top of the atmosphere for the whole ob- served Earth disc, due to its unique position in geostationary orbit. Every 15 minutes the GERB sensor will make a full Earth disc observation, centred on the Greenwich meridian. Thus, the GERB sensor will provide unprecedented coupled temporal and spatial resolution of the outgoing longwave radiation (4.0 to 30.0 microns), by first measuring the broadband radiation (0.32 to 30.0 microns) and then subtracting the measured reflected shortwave solar radiation (0.32 to 4.0 microns), from the earth- atmosphere system. The GERB sensor is able to make measurements to within an accuracy of 1 W/sq. m. A forward model is being developed at Leicester to simulate the data from the GERB sensor for representative geophysical scenes and to investigate key parameters and processes that will affect the top of the atmosphere signal. At the heart of this model is a line-by-line radiative transfer model, the Oxford Reference Forward Model (RFM) that is to be used with model atmospheres generated from ECMWF analysis data. When MSG is launched, cloud data from the Spinning Enhanced Visible and Infrared Imager (SEVIRI), also on board, is to be used in conjunction with GERB data.

  3. Design factors of sensors for the optical tracking systems of solar concentrators

    International Nuclear Information System (INIS)

    Klychev, Sh. I.; Fazylov, A. K.; Orlov, S. A.; Burbo, A. V.

    2011-01-01

    Basic diagrams for the sensors of the optical tracking systems of solar concentrators are considered, the design factors that determine their accuracy are analyzed, a new sensor design is suggested, and its optimal parameters are determined. (authors)

  4. Solar radiation is inversely associated with inflammatory bowel disease admissions.

    Science.gov (United States)

    Jaime, Francisca; Riutort, Maria C; Alvarez-Lobos, Manuel; Hoyos-Bachiloglu, Rodrigo; Camargo, Carlos A; Borzutzky, Arturo

    To explore the associations between latitude and solar radiation with inflammatory bowel disease admission rates in Chile, the country with the largest variation in solar radiation in the world. This is an ecological study, which included data on all hospital-admitted population for inflammatory bowel disease between 2001 and 2012, according to different latitudes and solar radiation exposures in Chile. The data were acquired from the national hospital discharge database from the Department of Health Statistics and Information of the Chilean Ministry of Health. Between 2001 and 2012 there were 12,869 admissions due to inflammatory bowel disease (69% ulcerative colitis, 31% Crohn's disease). Median age was 36 years (IQR: 25-51); 57% were female. The national inflammatory bowel disease admission rate was 6.52 (95% CI: 6.40-6.63) per 100,000 inhabitants with increasing rates over the 12-year period. In terms of latitude, the highest admission rates for pediatric ulcerative colitis and Crohn's disease, as well as adult ulcerative colitis, were observed in the southernmost region with lowest annual solar radiation. Linear regression analysis showed that regional solar radiation was inversely associated with inflammatory bowel disease admissions in Chile (β: -.44, p = .03). Regional solar radiation was inversely associated with inflammatory bowel disease admission rates in Chile; inflammatory bowel disease admissions were highest in the southernmost region with lowest solar radiation. Our results support the potential role of vitamin D deficiency on inflammatory bowel disease flares.

  5. NREL Solar Radiation Resource Assessment Project: Status and outlook

    Science.gov (United States)

    Renne, D.; Riordan, C.; Maxwell, E.; Stoffel, T.; Marion, B.; Rymes, M.; Wilcox, S.; Myers, D.

    1992-05-01

    This report summarizes the activities and accomplishments of NREL's Solar Radiation Resource Assessment Project during fiscal year 1991. Currently, the primary focus of the SRRAP is to produce a 1961 - 1990 National Solar Radiation Data Base, providing hourly values of global horizontal, diffuse, and direct normal solar radiation at approximately 250 sites around the United States. Because these solar radiation quantities were measured intermittently at only about 50 of these sites, models were developed and applied to the majority of the stations to provide estimates of these parameters. Although approximately 93 percent of the data base consists of modeled data this represents a significant improvement over the SOLMET/ERSATZ 1952 - 1975 data base. The magnitude and importance of this activity are such that the majority of SRRAP human and financial resources were devoted to the data base development. However, in FY 1991 the SRRAP was involved in many other activities, which are reported here. These include the continued maintenance of a solar radiation monitoring network in the southeast United States at six Historically Black Colleges and Universities (HBCU's), the transfer of solar radiation resource assessment technology through a variety of activities, participation in international programs, and the maintenance and operation of NREL's Solar Radiation Research Laboratory.

  6. Materials That Enhance Efficiency and Radiation Resistance of Solar Cells

    Science.gov (United States)

    Sun, Xiadong; Wang, Haorong

    2012-01-01

    A thin layer (approximately 10 microns) of a novel "transparent" fluorescent material is applied to existing solar cells or modules to effectively block and convert UV light, or other lower solar response waveband of solar radiation, to visible or IR light that can be more efficiently used by solar cells for additional photocurrent. Meanwhile, the layer of fluorescent coating material remains fully "transparent" to the visible and IR waveband of solar radiation, resulting in a net gain of solar cell efficiency. This innovation alters the effective solar spectral power distribution to which an existing cell gets exposed, and matches the maximum photovoltaic (PV) response of existing cells. By shifting a low PV response waveband (e.g., UV) of solar radiation to a high PV response waveband (e.g. Vis-Near IR) with novel fluorescent materials that are transparent to other solar-cell sensitive wavebands, electrical output from solar cells will be enhanced. This approach enhances the efficiency of solar cells by converting UV and high-energy particles in space that would otherwise be wasted to visible/IR light. This innovation is a generic technique that can be readily implemented to significantly increase efficiencies of both space and terrestrial solar cells, without incurring much cost, thus bringing a broad base of economical, social, and environmental benefits. The key to this approach is that the "fluorescent" material must be very efficient, and cannot block or attenuate the "desirable" and unconverted" waveband of solar radiation (e.g. Vis-NIR) from reaching the cells. Some nano-phosphors and novel organometallic complex materials have been identified that enhance the energy efficiency on some state-of-the-art commercial silicon and thin-film-based solar cells by over 6%.

  7. Modeling solar radiation at the Earth's surface recent advances

    CERN Document Server

    Badescu, Viorel

    2008-01-01

    Solar radiation data is important for a wide range of applications, e.g. in engineering, agriculture, health sector, and in many fields of the natural sciences. A few examples showing the diversity of applications may include: architecture and building design e.g. air conditioning and cooling systems; solar heating system design and use; solar power generation; weather and climate prediction models; evaporation and irrigation; calculation of water requirements for crops; monitoring plant growth and disease control; skin cancer research. Solar radiation data must be provided in a variety of f

  8. CLASSICS Handbook of Solar Radiation Data for India

    Indian Academy of Sciences (India)

    Srimath

    Handbook of Solar Radiation Data for India. By Anna Mani. CHAPTER 1. Introduction. 1.1. The sun and its radiation. The electromagnetic radiation emitted by the sun covers a very large range of wave- lengths, from radiowaves through the infrared, visible and ultraviolet to X-rays and gamma rays. However, 99 per cent of ...

  9. A Green Energy Application in Energy Management Systems by an Artificial Intelligence-Based Solar Radiation Forecasting Model

    Directory of Open Access Journals (Sweden)

    Ping-Huan Kuo

    2018-04-01

    Full Text Available The photovoltaic (PV systems generate green energy from the sunlight without any pollution or noise. The PV systems are simple, convenient to install, and seldom malfunction. Unfortunately, the energy generated by PV systems depends on climatic conditions, location, and system design. The solar radiation forecasting is important to the smooth operation of PV systems. However, solar radiation detected by a pyranometer sensor is strongly nonlinear and highly unstable. The PV energy generation makes a considerable contribution to the smart grids via a large number of relatively small PV systems. In this paper, a high-precision deep convolutional neural network model (SolarNet is proposed to facilitate the solar radiation forecasting. The proposed model is verified by experiments. The experimental results demonstrate that SolarNet outperforms other benchmark models in forecasting accuracy as well as in predicting complex time series with a high degree of volatility and irregularity.

  10. Estimation of monthly solar radiation distribution for solar energy system analysis

    International Nuclear Information System (INIS)

    Coskun, C.; Oktay, Z.; Dincer, I.

    2011-01-01

    The concept of probability density frequency, which is successfully used for analyses of wind speed and outdoor temperature distributions, is now modified and proposed for estimating solar radiation distributions for design and analysis of solar energy systems. In this study, global solar radiation distribution is comprehensively analyzed for photovoltaic (PV) panel and thermal collector systems. In this regard, a case study is conducted with actual global solar irradiation data of the last 15 years recorded by the Turkish State Meteorological Service. It is found that intensity of global solar irradiance greatly affects energy and exergy efficiencies and hence the performance of collectors. -- Research highlights: → The first study to apply global solar radiation distribution in solar system analyzes. → The first study showing global solar radiation distribution as a parameter of the solar irradiance intensity. → Time probability intensity frequency and probability power distribution do not have similar distribution patterns for each month. → There is no relation between the distribution of annual time lapse and solar energy with the intensity of solar irradiance.

  11. Evaluation of solar radiation abundance and electricity production capacity for application and development of solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Rahim, Mustamin [Department of Architecture, Khairun University, Ternate (Indonesia); Environmental and Renewable Energy Systems Division, Graduate School of Engineering, Gifu University (Japan); Yoshino, Jun; Yasuda, Takashi [Environmental and Renewable Energy Systems Division, Graduate School of Engineering, Gifu University (Japan)

    2012-07-01

    This study was undertaken to analyze solar radiation abundance to ascertain the potential of solar energy as an electrical energy resource. Local weather forecasting for predicting solar radiation is performed using a meteorological model MM5. The prediction results are compared with observed results obtained from the Japan Meteorological Agency for verification of the data accuracy. Results show that local weather forecasting has high accuracy. Prediction of solar radiation is similar with observation results. Monthly average values of solar radiation are sufficiently good during March–September. Electrical energy generated by photovoltaic cells is almost proportional to the solar radiation amount. Effects of clouds on solar radiation can be removed by monthly averaging. The balance between supply and demand of electricity can be estimated using a standard curve obtained from the temporal average. When the amount of solar radiation every hour with average of more than 100 km radius area does not yield the standard curve, we can estimate the system of storage and auxiliary power necessary based on the evaluated results of imbalance between supply and demand.

  12. Modelling solar radiation interception in row plantation. 3. Application to a traditional vineyard

    International Nuclear Information System (INIS)

    Sinoquet, H.; Valancogne, C.; Lescure, A.; Bonhomme, R.

    1992-01-01

    A previously described model of solar radiation interception was applied to a spatially discontinuous canopy: that of a traditional vineyard in which the classical terms of the radiative balance and the spatial distribution of the radiation transmitted to the soil were measured. Comparison of measured and simulated data gave satisfactory agreement for reflected radiation (fig 4), but major discrepancies appeared for mean transmitted radiation (fig 5). The use of small stationary sensors for measuring the transmitted radiation explains the latter observation, since most of the time they measured radiation received on the ground in the sunflecks or in the shaded area rather than mean radiation. This was verified by comparing the measured and simulated spatial distribution of transmitted radiation (figs 7, 8). Finally, the influence of the woody parts which were not taken into consideration in the model was clearly identified : it significantly reduced the transmission of incident radiation (fig 9), and to a greater degrees the closer the sensor was to the vegetation row. (author) [fr

  13. Protection from solar ultraviolet radiation by clothing

    Energy Technology Data Exchange (ETDEWEB)

    Pailthorpe, M. [New South Wales Univ., Kensington, NSW (Australia)

    1996-12-31

    The recently published Australia/New Zealand Standard AS/NZS 4399: l996 `Sun Protective Clothing - Evaluation and Classification` specifies an in vitro spectrophotometric method for the measurement of the ultraviolet (WR) transmission of textiles. Ultraviolet Protection Factors (UPF) are then calculated by convolving the UVR transmission data with standard CIE erythemal response data and ARL solar irradiance data. At the present time the scope of the standard is limited to loose fitting dry clothing. Virtually every textile parameter has an influence on the UPF of the finished garment and hence on the protection afforded to skin from the harmful effects of solar UVR radiation. Textile parameters such as fibre type, the method of spinning the yarn, fabric structure, cover factor, colorant, UVR absorbers and finishing methods determine the UPF of the fabric and hence must be controlled from batch to batch. Since garments generally shrink when washed, multiple wearing and washing cycles usually cause an increase in fabric UPF. Adventitious soiling of fabrics and the absorption of certain components of domestic laundry formulations, e g fluorescent whitening agents, increase fabric UPF ratings. Garments with a high degree of elasticity, e g nylon/lycra sportswear, that are stretched on to fit, will obviously have lower UPFs when stretched than when relaxed. In general fabrics worn in a wet state provide lower protection than when worn dry. On Australia`s most extreme summer day it has been estimated that there are 30 MEDs (minimal erythemal doses) in a dawn to dusk exposure. Thus outdoor workers should be provided with UPF 30 clothing, or better. Results from recent experiments using SK-II hairless mice dressed in UPF 50 `sunsuits` have shown that the mice developed no sun induced skin cancers on the skin areas protected by the UPF 50 fabric whereas multiple tumours developed on the unprotected skin.

  14. Protection from solar ultraviolet radiation by clothing

    International Nuclear Information System (INIS)

    Pailthorpe, M.

    1996-01-01

    The recently published Australia/New Zealand Standard AS/NZS 4399: l996 'Sun Protective Clothing - Evaluation and Classification' specifies an in vitro spectrophotometric method for the measurement of the ultraviolet (WR) transmission of textiles. Ultraviolet Protection Factors (UPF) are then calculated by convolving the UVR transmission data with standard CIE erythemal response data and ARL solar irradiance data. At the present time the scope of the standard is limited to loose fitting dry clothing. Virtually every textile parameter has an influence on the UPF of the finished garment and hence on the protection afforded to skin from the harmful effects of solar UVR radiation. Textile parameters such as fibre type, the method of spinning the yarn, fabric structure, cover factor, colorant, UVR absorbers and finishing methods determine the UPF of the fabric and hence must be controlled from batch to batch. Since garments generally shrink when washed, multiple wearing and washing cycles usually cause an increase in fabric UPF. Adventitious soiling of fabrics and the absorption of certain components of domestic laundry formulations, e g fluorescent whitening agents, increase fabric UPF ratings. Garments with a high degree of elasticity, e g nylon/lycra sportswear, that are stretched on to fit, will obviously have lower UPFs when stretched than when relaxed. In general fabrics worn in a wet state provide lower protection than when worn dry. On Australia's most extreme summer day it has been estimated that there are 30 MEDs (minimal erythemal doses) in a dawn to dusk exposure. Thus outdoor workers should be provided with UPF 30 clothing, or better. Results from recent experiments using SK-II hairless mice dressed in UPF 50 'sunsuits' have shown that the mice developed no sun induced skin cancers on the skin areas protected by the UPF 50 fabric whereas multiple tumours developed on the unprotected skin

  15. A simple solar radiation index for wildlife habitat studies

    Science.gov (United States)

    Keating, Kim A.; Gogan, Peter J.; Vore, John N.; Irby, Lynn R.

    2007-01-01

    Solar radiation is a potentially important covariate in many wildlife habitat studies, but it is typically addressed only indirectly, using problematic surrogates like aspect or hillshade. We devised a simple solar radiation index (SRI) that combines readily available information about aspect, slope, and latitude. Our SRI is proportional to the amount of extraterrestrial solar radiation theoretically striking an arbitrarily oriented surface during the hour surrounding solar noon on the equinox. Because it derives from first geometric principles and is linearly distributed, SRI offers clear advantages over aspect-based surrogates. The SRI also is superior to hillshade, which we found to be sometimes imprecise and ill-behaved. To illustrate application of our SRI, we assessed niche separation among 3 ungulate species along a single environmental axis, solar radiation, on the northern Yellowstone winter range. We detected no difference between the niches occupied by bighorn sheep (Ovis canadensis) and elk (Cervus elaphus; P = 0.104), but found that mule deer (Odocoileus hemionus) tended to use areas receiving more solar radiation than either of the other species (P solar radiation component.

  16. A theoretical approach to photosynthetically active radiation silicon sensor

    International Nuclear Information System (INIS)

    Tamasi, M.J.L.; Martínez Bogado, M.G.

    2013-01-01

    This paper presents a theoretical approach for the development of low cost radiometers to measure photosynthetically active radiation (PAR). Two alternatives are considered: a) glass optical filters attached to a silicon sensor, and b) dielectric coating on a silicon sensor. The devices proposed are based on radiometers previously developed by the Argentine National Atomic Energy Commission. The objective of this work is to adapt these low cost radiometers to construct reliable instruments for measuring PAR. The transmittance of optical filters and sensor response have been analyzed for different dielectric materials, number of layers deposited, and incidence angles. Uncertainties in thickness of layer deposition were evaluated. - Highlights: • Design of radiometers to measure photosynthetically active radiation • The study has used a filter and a Si sensor to modify spectral response. • Dielectric multilayers on glass and silicon sensor • Spectral response related to different incidence angles, materials and spectra

  17. Comparison of Solar UVA and UVB Radiation Measured in Selangor, Malaysia

    International Nuclear Information System (INIS)

    Kamarudin, S. U.; Gopir, G.; Yatim, B.; Sanusi, H.; Mahmud, P. S. Megat; Choo, P. Y.

    2010-01-01

    The solar ultraviolet A (UVA) radiation data was measured at Physics Building, Universiti Kebangsaan Malaysia (2 degree sign 55' N, 101 degree sign 46' E, 50m asl) by the Xplorer GLX Pasco that connected to UVA Light sensor. The measured solar UVA data were compared with the total daily solar ultraviolet B (UVB) radiation data recorded by the Malaysian Metrological Department at Petaling Jaya, Malaysia (3 degree sign 06' N, 101 degree sign 39' E, 50m asl) for 18 days in year 2007. The daily total average of UVA radiation received is (298±105) kJm -2 while the total daily maximum is (600±56) kJm -2 . From the analysis, it shows that the values of UVA radiation data were higher than UVB radiation data with the average ratio of 6.41% between 3-14%. A weak positive correlation was found (the correlation coefficient, r, is 0.22). The amount of UVA radiation that reached the earth surface is less dependence on UVB radiation and the factors were discussed.

  18. Modelling radiative heat transfer inside a basin type solar still

    International Nuclear Information System (INIS)

    Madhlopa, A.

    2014-01-01

    Radiative heat transfer inside a basin type solar still has been investigated using two models with (model 1) and without (model 2) taking into account optical view factors. The coefficient of radiative heat exchange (h r,w-gc ) between the water and cover surfaces of a practical solar still was computed using the two models. Simulation results show that model 1 yields lower values of h r,w-gc and the root mean square error than model 2. It is therefore concluded that the accuracy of modelling the performance of a basin-type solar still can be improved by incorporating view factors. - Highlights: • Radiative heat transfer in a basin type solar still has been investigated. • Two models with and without view factors were used. • The model with view factors exhibits a lower magnitude of root mean square error. • View factors affect the accuracy of modelling the performance of the solar still

  19. Solar radiation and mitochondrial DNA damage

    International Nuclear Information System (INIS)

    Hill, H.Z.; Locitzer, J.; Nassrin, E.; Ogbonnaya, A.; Hubbard, K.

    2003-01-01

    The 16.6 kB human mitochondrial DNA contains two homologous 13 base pair direct repeats separated by about 5 kB. During asynchronous mitochondrial DNA replication, the distant repeat sequences are thought to anneal, resulting in the looping out of a portion of the non-template strand which is subsequently deleted as a result of interaction with reactive oxygen species (ROS). A normal daughter and a deleted daughter mitochondrion result from such insults. This deletion has been termed the common deletion as it is the most frequent of the known mitochondrial DNA deletions. The common deletion is present in high frequency in several mitochondrial disorders, accumulates with age in slow turnover tissues and is increased in sun-exposed skin. Berneburg, et al. (Photochem. Photobiol. 66: 271, 1997) induced the common deletion in normal human fibroblasts after repeated exposures to UVA. In this study, the common deletion has been shown to be induced by repeated non-lethal exposures to FS20 sunlamp irradiation. Increases in the common deletion were demonstrated using nested PCR which produced a 303 bp product that was compared to a 324 bp product that required the presence of the undeleted 5 kB region. The cells were exposed to 10 repeated doses ranging from 0.5 (UVB) - 0.24 (UVA) J/sq m to 14.4 (UVB) - 5.8 J/sq m (UVA) measured using a UVX digital radiometer and UVB and UVA detectors respectively. Comparison with the earlier study by Berneberg, et al. suggests that this type of simulated solar damage is considerably more effective in fewer exposures than UVA radiation alone. The common deletion provides a cytoplasmic end-point for ROS damage produced by low dose chronic irradiations and other low level toxic exposures and should prove useful in evaluating cytoplasmic damage produced by ionizing radiation as well

  20. Solar radiation and its penetration in a tropical estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Qasim, S.Z.; Bhattathiri, P.M.A.; Abidi, S.A.H.

    The Cochin Backwater which is an estuarine area on the west coast of India receives maximum solar radiation from December to March and minimum from June to September. During the monsoon months the estuary becomes highly turbid as a result...

  1. The growth of solar radiated yeast

    Energy Technology Data Exchange (ETDEWEB)

    Kraft, T.

    1995-09-01

    This researcher plans to determine if solar radiation affects the growth of yeast. The irradiated yeast was obtained from a sample exposed in space during a Space Shuttle flight of September 9-20, 1994. Further, the control groups were held at: (1) Goddard Space Flight Center (GSFC) in Greenbelt, Maryland; and (2) South Dakota School of Mines and Technology. The procedure used was based on the fact that yeast is most often used in consumable baked goods. Therefore, the yeast was incorporated into a basic Betty Crocker bread recipe. Data was collected by placing measured amounts of dough into sample containers with fifteen minute growth in height measurements collected and recorded. This researcher assumed the viability of yeast to be relative to its ability to produce carbon dioxide gas and cause the dough to rise. As all ingredients and surroundings were equal, this researcher assumed the yeast will produce the only significant difference in data collected. This researcher noted the approximate use date on all sample packages to be prior to arrival and experiment date. All dates equal, it was then assumed each would act in a similar manner of response. This assumption will allow for equally correct data collection.

  2. The growth of solar radiated yeast

    Science.gov (United States)

    Kraft, Tyrone

    1995-01-01

    This researcher plans to determine if solar radiation affects the growth of yeast. The irradiated yeast was obtained from a sample exposed in space during a Space Shuttle flight of September 9-20, 1994. Further, the control groups were held at: (1) Goddard Space Flight Center (GSFC) in Greenbelt, Maryland; and (2) South Dakota School of Mines and Technology. The procedure used was based on the fact that yeast is most often used in consumable baked goods. Therefore, the yeast was incorporated into a basic Betty Crocker bread recipe. Data was collected by placing measured amounts of dough into sample containers with fifteen minute growth in height measurements collected and recorded. This researcher assumed the viability of yeast to be relative to its ability to produce carbon dioxide gas and cause the dough to rise. As all ingredients and surroundings were equal, this researcher assumed the yeast will produce the only significant difference in data collected. This researcher noted the approximate use date on all sample packages to be prior to arrival and experiment date. All dates equal, it was then assumed each would act in a similar manner of response. This assumption will allow for equally correct data collection.

  3. Denoising solar radiation data using coiflet wavelets

    Energy Technology Data Exchange (ETDEWEB)

    Karim, Samsul Ariffin Abdul, E-mail: samsul-ariffin@petronas.com.my; Janier, Josefina B., E-mail: josefinajanier@petronas.com.my; Muthuvalu, Mohana Sundaram, E-mail: mohana.muthuvalu@petronas.com.my [Department of Fundamental and Applied Sciences, Faculty of Sciences and Information Technology, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak Darul Ridzuan (Malaysia); Hasan, Mohammad Khatim, E-mail: khatim@ftsm.ukm.my [Jabatan Komputeran Industri, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Sulaiman, Jumat, E-mail: jumat@ums.edu.my [Program Matematik dengan Ekonomi, Universiti Malaysia Sabah, Beg Berkunci 2073, 88999 Kota Kinabalu, Sabah (Malaysia); Ismail, Mohd Tahir [School of Mathematical Sciences, Universiti Sains Malaysia, 11800 USM Minden, Penang (Malaysia)

    2014-10-24

    Signal denoising and smoothing plays an important role in processing the given signal either from experiment or data collection through observations. Data collection usually was mixed between true data and some error or noise. This noise might be coming from the apparatus to measure or collect the data or human error in handling the data. Normally before the data is use for further processing purposes, the unwanted noise need to be filtered out. One of the efficient methods that can be used to filter the data is wavelet transform. Due to the fact that the received solar radiation data fluctuates according to time, there exist few unwanted oscillation namely noise and it must be filtered out before the data is used for developing mathematical model. In order to apply denoising using wavelet transform (WT), the thresholding values need to be calculated. In this paper the new thresholding approach is proposed. The coiflet2 wavelet with variation diminishing 4 is utilized for our purpose. From numerical results it can be seen clearly that, the new thresholding approach give better results as compare with existing approach namely global thresholding value.

  4. An economic evaluation of solar radiation management

    Energy Technology Data Exchange (ETDEWEB)

    Aaheim, Asbjørn; Romstad, Bård; Wei, Taoyuan [CICERO — Center for International Climate and Environmental Research Oslo (Norway); Kristjánsson, Jón Egill; Muri, Helene [Department of Geosciences, University of Oslo (Norway); Niemeier, Ulrike; Schmidt, Hauke [Max Planck Institute for Meteorology, Hamburg (Germany)

    2015-11-01

    Economic evaluations of solar radiation management (SRM) usually assume that the temperature will be stabilized, with no economic impacts of climate change, but with possible side-effects. We know from experiments with climate models, however, that unlike emission control the spatial and temporal distributions of temperature, precipitation and wind conditions will change. Hence, SRM may have economic consequences under a stabilization of global mean temperature even if side-effects other than those related to the climatic responses are disregarded. This paper addresses the economic impacts of implementing two SRM technologies; stratospheric sulfur injection and marine cloud brightening. By the use of a computable general equilibrium model, we estimate the economic impacts of climatic responses based on the results from two earth system models, MPI-ESM and NorESM. We find that under a moderately increasing greenhouse-gas concentration path, RCP4.5, the economic benefits of implementing climate engineering are small, and may become negative. Global GDP increases in three of the four experiments and all experiments include regions where the benefits from climate engineering are negative.

  5. Public understanding of solar radiation management

    International Nuclear Information System (INIS)

    Mercer, A M; Keith, D W; Sharp, J D

    2011-01-01

    We report the results of the first large-scale international survey of public perception of geoengineering and solar radiation management (SRM). Our sample of 3105 individuals in the United States, Canada and the United Kingdom was recruited by survey firms that administer internet surveys to nationally representative population samples. Measured familiarity was higher than expected, with 8% and 45% of the population correctly defining the terms geoengineering and climate engineering respectively. There was strong support for allowing the study of SRM. Support decreased and uncertainty rose as subjects were asked about their support for using SRM immediately, or to stop a climate emergency. Support for SRM is associated with optimism about scientific research, a valuing of SRM's benefits and a stronger belief that SRM is natural, while opposition is associated with an attitude that nature should not be manipulated in this way. The potential risks of SRM are important drivers of public perception with the most salient being damage to the ozone layer and unknown risks. SRM is a new technology and public opinions are just forming; thus all reported results are sensitive to changes in framing, future information on risks and benefits, and changes to context.

  6. An economic evaluation of solar radiation management

    International Nuclear Information System (INIS)

    Aaheim, Asbjørn; Romstad, Bård; Wei, Taoyuan; Kristjánsson, Jón Egill; Muri, Helene; Niemeier, Ulrike; Schmidt, Hauke

    2015-01-01

    Economic evaluations of solar radiation management (SRM) usually assume that the temperature will be stabilized, with no economic impacts of climate change, but with possible side-effects. We know from experiments with climate models, however, that unlike emission control the spatial and temporal distributions of temperature, precipitation and wind conditions will change. Hence, SRM may have economic consequences under a stabilization of global mean temperature even if side-effects other than those related to the climatic responses are disregarded. This paper addresses the economic impacts of implementing two SRM technologies; stratospheric sulfur injection and marine cloud brightening. By the use of a computable general equilibrium model, we estimate the economic impacts of climatic responses based on the results from two earth system models, MPI-ESM and NorESM. We find that under a moderately increasing greenhouse-gas concentration path, RCP4.5, the economic benefits of implementing climate engineering are small, and may become negative. Global GDP increases in three of the four experiments and all experiments include regions where the benefits from climate engineering are negative

  7. Development of radiation hardened pixel sensors for charged particle detection

    CERN Document Server

    Koziel, Michal

    2014-01-01

    CMOS Pixel Sensors are being developed since a few years to equip vertex detectors for future high-energy physics experiments with the crucial advantages of a low material budget and low production costs. The features simultaneously required are a short readout time, high granularity and high tolerance to radiation. This thesis mainly focuses on the radiation tolerance studies. To achieve the targeted readout time (tens of microseconds), the sensor pixel readout was organized in parallel columns restricting in addition the readout to pixels that had collected the signal charge. The pixels became then more complex, and consequently more sensitive to radiation. Different in-pixel architectures were studied and it was concluded that the tolerance to ionizing radiation was limited to 300 krad with the 0.35- m fabrication process currently used, while the targeted value was several Mrad. Improving this situation calls for implementation of the sensors in processes with a smaller feature size which naturally imp...

  8. Air temperature sensors: dependence of radiative errors on sensor diameter in precision metrology and meteorology

    Science.gov (United States)

    de Podesta, Michael; Bell, Stephanie; Underwood, Robin

    2018-04-01

    In both meteorological and metrological applications, it is well known that air temperature sensors are susceptible to radiative errors. However, it is not widely known that the radiative error measured by an air temperature sensor in flowing air depends upon the sensor diameter, with smaller sensors reporting values closer to true air temperature. This is not a transient effect related to sensor heat capacity, but a fluid-dynamical effect arising from heat and mass flow in cylindrical geometries. This result has been known historically and is in meteorology text books. However, its significance does not appear to be widely appreciated and, as a consequence, air temperature can be—and probably is being—widely mis-estimated. In this paper, we first review prior descriptions of the ‘sensor size’ effect from the metrological and meteorological literature. We develop a heat transfer model to describe the process for cylindrical sensors, and evaluate the predicted temperature error for a range of sensor sizes and air speeds. We compare these predictions with published predictions and measurements. We report measurements demonstrating this effect in two laboratories at NPL in which the air flow and temperature are exceptionally closely controlled. The results are consistent with the heat-transfer model, and show that the air temperature error is proportional to the square root of the sensor diameter and that, even under good laboratory conditions, it can exceed 0.1 °C for a 6 mm diameter sensor. We then consider the implications of this result. In metrological applications, errors of the order of 0.1 °C are significant, representing limiting uncertainties in dimensional and mass measurements. In meteorological applications, radiative errors can easily be much larger. But in both cases, an understanding of the diameter dependence allows assessment and correction of the radiative error using a multi-sensor technique.

  9. Improved Statistical Model Of 10.7-cm Solar Radiation

    Science.gov (United States)

    Vedder, John D.; Tabor, Jill L.

    1993-01-01

    Improved mathematical model simulates short-term fluctuations of flux of 10.7-cm-wavelength solar radiation during 91-day averaging period. Called "F10.7 flux", important as measure of solar activity and because it is highly correlated with ultraviolet radiation causing fluctuations in heating and density of upper atmosphere. F10.7 flux easily measureable at surface of Earth.

  10. Differential multi-MOSFET nuclear radiation sensor

    Science.gov (United States)

    Deoliveira, W. A.

    1977-01-01

    Circuit allows minimization of thermal-drift errors, low power consumption, operation over wide dynamic range, improved sensitivity and stability with metaloxide-semiconductor field-effect transistor sensors.

  11. Estimating surface solar radiation from upper-air humidity

    Energy Technology Data Exchange (ETDEWEB)

    Kun Yang [Telecommunications Advancement Organization of Japan, Tokyo (Japan); Koike, Toshio [University of Tokyo (Japan). Dept. of Civil Engineering

    2002-07-01

    A numerical model is developed to estimate global solar irradiance from upper-air humidity. In this model, solar radiation under clear skies is calculated through a simple model with radiation-damping processes under consideration. A sky clearness indicator is parameterized from relative humidity profiles within three atmospheric sublayers, and the indicator is used to connect global solar radiation under clear skies and that under cloudy skies. Model inter-comparisons at 18 sites in Japan suggest (1) global solar radiation strongly depends on the sky clearness indicator, (2) the new model generally gives better estimation to hourly-mean solar irradiance than the other three methods used in numerical weather predictions, and (3) the new model may be applied to estimate long-term solar radiation. In addition, a study at one site in the Tibetan Plateau shows vigorous convective activities in the region may cause some uncertainties to radiation estimations due to the small-scale and short life of convective systems. (author)

  12. Prostate cancer incidence in Australia correlates inversely with solar radiation.

    Science.gov (United States)

    Loke, Tim W; Seyfi, Doruk; Sevfi, Doruk; Khadra, Mohamed

    2011-11-01

    What's known on the subject? and What does the study add? Increased sun exposure and blood levels of vitamin D have been postulated to be protective against prostate cancer. This is controversial. We investigated the relationship between prostate cancer incidence and solar radiation in non-urban Australia, and found a lower incidence in regions receiving more sunlight. In landmark ecological studies, prostate cancer mortality rates have been shown to be inversely related to ultraviolet radiation exposure. Investigators have hypothesised that ultraviolet radiation acts by increasing production of vitamin D, which inhibits prostate cancer cells in vitro. However, analyses of serum levels of vitamin D in men with prostate cancer have failed to support this hypothesis. This study has found an inverse correlation between solar radiation and prostate cancer incidence in Australia. Our population (previously unstudied) represents the third group to exhibit this correlation. Significantly, the demographics and climate of Australia differ markedly from those of previous studies conducted on men in the United Kingdom and the United States. • To ascertain if prostate cancer incidence rates correlate with solar radiation among non-urban populations of men in Australia. • Local government areas from each state and territory were selected using explicit criteria. Urban areas were excluded from analysis. • For each local government area, prostate cancer incidence rates and averaged long-term solar radiation were obtained. • The strength of the association between prostate cancer incidence and solar radiation was determined. • Among 70 local government areas of Australia, age-standardized prostate cancer incidence rates for the period 1998-2007 correlated inversely with daily solar radiation averaged over the last two decades. •  There exists an association between less solar radiation and higher prostate cancer incidence in Australia. © 2011 THE AUTHORS. BJU

  13. Total and Spectral Solar Irradiance Sensor (TSIS) Project Status

    Science.gov (United States)

    Carlisle, Candace

    2018-01-01

    TSIS-1 studies the Sun's energy input to Earth and how solar variability affects climate. TSIS-1 will measure both the total amount of light that falls on Earth, known as the total solar irradiance (TSI), and how that light is distributed among ultraviolet, visible and infrared wavelengths, called solar spectral irradiance (SSI). TSIS-1 will provide the most accurate measurements of sunlight and continue the long-term climate data record. TSIS-1 includes two instruments: the Total Irradiance Monitor (TIM) and the Spectral Irradiance Monitor (SIM), integrated into a single payload on the International Space Station (ISS). The TSIS-1 TIM and SIM instruments are upgraded versions of the two instruments that are flying on the Solar Radiation and Climate Experiment (SORCE) mission launched in January 2003. NASA Goddard's TSIS project responsibilities include project management, system engineering, safety and mission assurance, and engineering oversight for TSIS-1. TSIS-1 was installed on the International Space Station in December 2017. At the end of the 90-day commissioning phase, responsibility for TSIS-1 operations transitions to the Earth Science Mission Operations (ESMO) project at Goddard for its 5-year operations. NASA contracts with the University of Colorado Laboratory for Atmospheric and Space Physics (LASP) for the design, development and testing of TSIS-1, support for ISS integration, science operations of the TSIS-1 instrument, data processing, data evaluation, calibration and delivery to the Goddard Earth Science Data and Information Services Center (GES DISC).

  14. On the Modeling of Solar-Powered Wireless Sensor Nodes

    Directory of Open Access Journals (Sweden)

    Sebastian Bader

    2014-08-01

    Full Text Available Solar energy harvesting allows for wireless sensor networks to be operated over extended periods of time. In order to select an appropriate harvesting architecture and dimension for its components, an effective method for the comparison of system implementations is required. System simulations have the capability to accomplish this in an accurate and efficient manner. In this paper, we evaluate the existing work on solar energy harvesting architectures and common methods for their modeling. An analysis of the existing approaches demonstrates a mismatch between the requirement of the task to be both accurate and efficient and the proposed modeling methods, which are either accurate or efficient. As a result, we propose a data-driven modeling method based on artificial neural networks for further evaluation by the research community. Preliminary results of an initial investigation demonstrate the capability of this method to accurately capture the behavior of a solar energy harvesting architecture, while providing a time-efficient model generation procedure based on system-level data.

  15. Diffuse solar radiation and associated meteorological parameters in India

    Directory of Open Access Journals (Sweden)

    A. B. Bhattacharya

    Full Text Available Solar diffuse radiation data including global radiation, shortwave and longwave balances, net radiation and sunshine hours have been extensively analyzed to study the variation of diffuse radiation with turbidity and cloud discharges appearing in the form of atmospherics over the tropics. Results of surface radiation measurements at Calcutta, Poona, Delhi and Madras are presented together with some meteorological parameters. The monthly values of diffuse radiation and the monthly ratios of diffuse to global solar radiation have been examined, with a special emphasis in relation to the noise level of atmospherics at Calcutta in the very low frequency band. The results exhibit some definite seasonal changes which appear to be in close agreement with one another.

  16. New Temperature-based Models for Predicting Global Solar Radiation

    International Nuclear Information System (INIS)

    Hassan, Gasser E.; Youssef, M. Elsayed; Mohamed, Zahraa E.; Ali, Mohamed A.; Hanafy, Ahmed A.

    2016-01-01

    Highlights: • New temperature-based models for estimating solar radiation are investigated. • The models are validated against 20-years measured data of global solar radiation. • The new temperature-based model shows the best performance for coastal sites. • The new temperature-based model is more accurate than the sunshine-based models. • The new model is highly applicable with weather temperature forecast techniques. - Abstract: This study presents new ambient-temperature-based models for estimating global solar radiation as alternatives to the widely used sunshine-based models owing to the unavailability of sunshine data at all locations around the world. Seventeen new temperature-based models are established, validated and compared with other three models proposed in the literature (the Annandale, Allen and Goodin models) to estimate the monthly average daily global solar radiation on a horizontal surface. These models are developed using a 20-year measured dataset of global solar radiation for the case study location (Lat. 30°51′N and long. 29°34′E), and then, the general formulae of the newly suggested models are examined for ten different locations around Egypt. Moreover, the local formulae for the models are established and validated for two coastal locations where the general formulae give inaccurate predictions. Mostly common statistical errors are utilized to evaluate the performance of these models and identify the most accurate model. The obtained results show that the local formula for the most accurate new model provides good predictions for global solar radiation at different locations, especially at coastal sites. Moreover, the local and general formulas of the most accurate temperature-based model also perform better than the two most accurate sunshine-based models from the literature. The quick and accurate estimations of the global solar radiation using this approach can be employed in the design and evaluation of performance for

  17. Solar radiation and thermal performance of solar collectors for Denmark

    DEFF Research Database (Denmark)

    Dragsted, Janne; Furbo, Simon

    This report describes the part of the EUDP project “EUDP 11-l, Solar Resource Assessment in Denmark”, which is carried out at Department of Civil Engineering, Technical University of Denmark.......This report describes the part of the EUDP project “EUDP 11-l, Solar Resource Assessment in Denmark”, which is carried out at Department of Civil Engineering, Technical University of Denmark....

  18. UV radiation hardness of silicon inversion layer solar cells

    International Nuclear Information System (INIS)

    Hezel, R.

    1990-01-01

    For full utilization of the high spectral response of inversion layer solar cells in the very-short-wavelength range of the solar spectrum sufficient ultraviolet-radiation hardness is required. In addition to the charge-induced passivation achieved by cesium incorporation into the silicon nitride AR coating, in this paper the following means for further drastic reduction of UV light-induced effects in inversion layer solar cells without encapsulation are introduced and interpretations are given: increasing the nitride deposition temperature, silicon surface oxidation at low temperatures, and texture etching and using higher substrate resistivities. High UV radiation tolerance and improvement of the cell efficiency could be obtained simultaneously

  19. Solar Radiation Model for Development and Control of Solar Energy Sources

    Directory of Open Access Journals (Sweden)

    Dominykas Vasarevičius

    2016-06-01

    Full Text Available The model of solar radiation, which takes into account direct, diffused and reflected components of solar energy, has been presented. Model is associated with geographical coordinates and local time of every day of the year. It is shown that using analytic equations for modelling the direct component, it is possible to adopt it for embedded systems with low computational power and use in solar tracking applications. Reflected and diffused components are especially useful in determining the performance of photovoltaic modules in certain location and surroundings. The statistical method for cloud layer simulation based on local meteorological data is offered. The presented method can’t be used for prediction of weather conditions but it provides patterns of solar radiation in time comparable to those measured with pyranometer. Cloud layer simulation together with total solar radiation model is a useful tool for development and analysis of maximum power point tracking controllers for PV modules.

  20. Optical Fibre Temperature Sensor Based On A Blackbody Radiation

    Science.gov (United States)

    Hypszer, Ryszard; Plucinski, Jerzy; Wierzba, Henryk J.

    1990-01-01

    The principle of operation of the fibre optical temperature sensor based on a blackbody radiation and its construction model is given in the paper. A quartz rod of 0.6 mm diameter and 20 cm length with a blackbody cavity at the one end was used to construct the sensor. The cavity was made by vacuum evaporation of a chromium layer and a silicone monooxide layer was used as a protection. Infrared radiation is transmitted by the fibre optic to the detection circuit. This sensor enables temperature measurement from 400 to 1200°C. The range of measurement is determined by the detection sensitivity and by rod softening. The resolution is of the order of 10-2°C. The sensor calibration was done by using PtRh1O-Pt thermocouple.

  1. EVALUATION OF OPPORTUNITIES OF SOLAR ENERGETICS ON THE BASIS OF ACCURATE GROUND-BASED MEASUREMENTS OF SOLAR RADIATION

    Directory of Open Access Journals (Sweden)

    Aculinin A.

    2008-04-01

    Full Text Available Expected quantity of a solar energy received by solar panel is estimated on the basis of accurate measurements of solar radiation in Kishinev. Optimal orientation of solar panels and apparent volume of the electric power generated by solar panels are determined.

  2. Efficiency of solar radiation conversion in photovoltaic panels

    Directory of Open Access Journals (Sweden)

    Kurpaska Sławomir

    2018-01-01

    Full Text Available This paper included analysis the conversion efficiency in photovoltaic panels. The tests were done between February and June at a test stand equipped with three commonly used types of photovoltaic panels: poly- and monocrystalline silicon and with semi-conductive layer made of copper (Cu, indium (In, gallium (Ga and selenium (Se (CIGS. Five days of each month were selected for a detailed analysis. They were close to the so-called recommended day for calculations in solar power engineering. Efficiency, calculated as the yield of electrical energy in relation to solar radiation energy reaching the panels was made conditional upon solar radiation intensity and ambient temperature. It was found that as solar radiation intensity and ambient temperature increase, the efficiency of solar radiation conversion into electricity is reduced. Correlation dependence was determined for the test data obtained, describing temperature change of panels depending on climatic conditions. It was found that as panel temperature increases, the conversion efficiency is reduced. Within the tested scope of experiment conditions, the efficiency was reduced in the range between 20.1 and 22.8%. The authors also determined the average efficiency values in individual test months together with average ambient conditions of the environment where the process of solar radiation conversion took place.

  3. Radiative hazard of solar flares in the nearterrestrial cosmic space

    International Nuclear Information System (INIS)

    Kolomenskij, A.V.; Petrov, V.M.; Zil', M.V.; Eremkina, T.M.

    1978-01-01

    Simulation of radiation enviroment due to solar cosmic rays was carried out in the near-terrestrial space. Systematized are the data on cosmic ray flux and spectra detected during 19-th and 20-th cycles of solar activity. 127 flares are considered with proton fluxes of more than 10 proton/cm 2 at energies higher than 30 MeV. Obtained are distribution functions of intervals between flares, flux distribution of flares and characteristic rigidity, and also distribution of magnetic disturbances over Dsub(st)-variation amplitude. The totality of these distributions presents the statistic model of radiation enviroment caused by solar flare protons for the period of maximum solar .activity. This model is intended for estimation of radiation hazard at manned cosmic flights

  4. Effects of solar electromagnetic radiation on the terrestrial environment

    International Nuclear Information System (INIS)

    Dickinson, R.E.

    1986-01-01

    The general intent of this essay is to discuss the effect of solar electromagnetic radiation on the terrestrial environment. Instead of giving a systematic approach considering all environment processes where solar emission is the primary energy source and all important materials which have been generated by solar driven processes, the author sketches an impression of the range of the effects of solar radiation on the environment by surveying a number of topics of particular current interest, in varying levels of detail. These include atmospheric chemistry, some aspects of the transfer of radiation within the atmosphere, global energy balance and climate feedbacks, especially those due to clouds, impacts of fossil fuel energy use, evolution of early life processes, photosynthesis and plant productivity as it relates to photosynthesis and the global carbon cycle. (Auth.)

  5. The virtual enhancements - solar proton event radiation (VESPER) model

    Science.gov (United States)

    Aminalragia-Giamini, Sigiava; Sandberg, Ingmar; Papadimitriou, Constantinos; Daglis, Ioannis A.; Jiggens, Piers

    2018-02-01

    A new probabilistic model introducing a novel paradigm for the modelling of the solar proton environment at 1 AU is presented. The virtual enhancements - solar proton event radiation model (VESPER) uses the European space agency's solar energetic particle environment modelling (SEPEM) Reference Dataset and produces virtual time-series of proton differential fluxes. In this regard it fundamentally diverges from the approach of existing SPE models that are based on probabilistic descriptions of SPE macroscopic characteristics such as peak flux and cumulative fluence. It is shown that VESPER reproduces well the dataset characteristics it uses, and further comparisons with existing models are made with respect to their results. The production of time-series as the main output of the model opens a straightforward way for the calculation of solar proton radiation effects in terms of time-series and the pairing with effects caused by trapped radiation and galactic cosmic rays.

  6. National Solar Radiation Database (NSRDB) SolarAnywhere 10 km Model Output for 1989 to 2009

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Solar Radiation Database (NSRDB) was produced by the National Renewable Energy Laboratory under the U.S. Department of Energy's Office of Energy...

  7. Radiation hardness of diamond and silicon sensors compared

    CERN Document Server

    de Boer, Wim; Furgeri, Alexander; Mueller, Steffen; Sander, Christian; Berdermann, Eleni; Pomorski, Michal; Huhtinen, Mika

    2007-01-01

    The radiation hardness of silicon charged particle sensors is compared with single crystal and polycrystalline diamond sensors, both experimentally and theoretically. It is shown that for Si- and C-sensors, the NIEL hypothesis, which states that the signal loss is proportional to the Non-Ionizing Energy Loss, is a good approximation to the present data. At incident proton and neutron energies well above 0.1 GeV the radiation damage is dominated by the inelastic cross section, while at non-relativistic energies the elastic cross section prevails. The smaller inelastic nucleon-Carbon cross section and the light nuclear fragments imply that at high energies diamond is an order of magnitude more radiation hard than silicon, while at energies below 0.1 GeV the difference becomes significantly smaller.

  8. Assessment of integrated solar ultraviolet radiation by PM-355 detectors

    International Nuclear Information System (INIS)

    Abu-Jarad, F.; Al-Jarallah, M.I.; Elhadidy, M.A.; Shaahid, S.M.; Fazal-ur-Rehman

    2000-01-01

    The increase in environmental solar UV radiation due to depletion of ozone layer is a recent challenge to human health (skin cancer and eye effects) in countries having clear skies. Therefore, applying integrated, passive and inexpensive techniques to assess solar UV radiation is very much essential. Measurements of environmental solar UV radiation in Dhahran, Saudi Arabia area were carried out for a period of two months in the summer period in 1996 using two techniques in parallel namely: passive nuclear track detectors and active solar UV radiometers. Some of the nuclear track detectors were mounted in different conditions such as: under shadow band, on solar tracking mechanism following the solar rays. Others were mounted on perpendicular, tilted and horizontal surfaces in sunlight. All detectors were attached to a wooden background of the same thickness (0.5 cm) to eliminate interference of the heat effect of various support materials and have uniformity of the support materials. The assessment was carried out for different periods extending from two to nine weeks continuously. The investigated period covered the hottest months in Saudi Arabia (July and August) when the sky was clear of clouds. The results indicate linear correlation between alpha track diameters and the integrated exposure to solar UV as measured by the solar UV radiometer for all nuclear track detector positions and orientations. The highest slope has been observed for the detectors placed on solar tracking mechanism following the solar rays and the lowest from detectors oriented under the shadow band on horizontal position (measuring the diffused UV radiation only). The results show that most of the measured UV radiation (60%) were from the diffused UV radiation. The characteristics of the upper layer of the detectors are changed after chemical etching very quickly, with increase in the exposure time to UV solar radiation at certain orientation. The results encourage the use of nuclear track

  9. Assessment of integrated solar ultraviolet radiation by PM-355 detectors

    Energy Technology Data Exchange (ETDEWEB)

    Abu-Jarad, F.; Al-Jarallah, M.I.; Elhadidy, M.A.; Shaahid, S.M.; Fazal-ur-Rehman

    2000-06-01

    The increase in environmental solar UV radiation due to depletion of ozone layer is a recent challenge to human health (skin cancer and eye effects) in countries having clear skies. Therefore, applying integrated, passive and inexpensive techniques to assess solar UV radiation is very much essential. Measurements of environmental solar UV radiation in Dhahran, Saudi Arabia area were carried out for a period of two months in the summer period in 1996 using two techniques in parallel namely: passive nuclear track detectors and active solar UV radiometers. Some of the nuclear track detectors were mounted in different conditions such as: under shadow band, on solar tracking mechanism following the solar rays. Others were mounted on perpendicular, tilted and horizontal surfaces in sunlight. All detectors were attached to a wooden background of the same thickness (0.5 cm) to eliminate interference of the heat effect of various support materials and have uniformity of the support materials. The assessment was carried out for different periods extending from two to nine weeks continuously. The investigated period covered the hottest months in Saudi Arabia (July and August) when the sky was clear of clouds. The results indicate linear correlation between alpha track diameters and the integrated exposure to solar UV as measured by the solar UV radiometer for all nuclear track detector positions and orientations. The highest slope has been observed for the detectors placed on solar tracking mechanism following the solar rays and the lowest from detectors oriented under the shadow band on horizontal position (measuring the diffused UV radiation only). The results show that most of the measured UV radiation (60%) were from the diffused UV radiation. The characteristics of the upper layer of the detectors are changed after chemical etching very quickly, with increase in the exposure time to UV solar radiation at certain orientation. The results encourage the use of nuclear track

  10. Estimation of diffuse from measured global solar radiation

    International Nuclear Information System (INIS)

    Moriarty, W.W.

    1991-01-01

    A data set of quality controlled radiation observations from stations scattered throughout Australia was formed and further screened to remove residual doubtful observations. It was then divided into groups by solar elevation, and used to find average relationships for each elevation group between relative global radiation (clearness index - the measured global radiation expressed as a proportion of the radiation on a horizontal surface at the top of the atmosphere) and relative diffuse radiation. Clear-cut relationships were found, which were then fitted by polynomial expressions giving the relative diffuse radiation as a function of relative global radiation and solar elevation. When these expressions were used to estimate the diffuse radiation from the global, the results had a slightly smaller spread of errors than those from an earlier technique given by Spencer. It was found that the errors were related to cloud amount, and further relationships were developed giving the errors as functions of global radiation, solar elevation, and the fraction of sky obscured by high cloud and by opaque (low and middle level) cloud. When these relationships were used to adjust the first estimates of diffuse radiation, there was a considerable reduction in the number of large errors

  11. The Potential of Heat Collection from Solar Radiation in Asphalt Solar Collectors in Malaysia

    Science.gov (United States)

    Beddu, Salmia; Talib, Siti Hidayah Abdul; Itam, Zarina

    2016-03-01

    The implementation of asphalt solar collectors as a means of an energy source is being widely studied in recent years. Asphalt pavements are exposed to daily solar radiation, and are capable of reaching up to 70°C in temperature. The potential of harvesting energy from solar pavements as an alternative energy source in replace of non-renewable energy sources prone to depletion such as fuel is promising. In Malaysia, the sun intensity is quite high and for this reason, absorbing the heat from sun radiation, and then utilizing it in many other applications such as generating electricity could definitely be impressive. Previous researches on the different methods of studying the effect of heat absorption caused by solar radiation prove to be quite old and inaffective. More recent findings, on the otherhand, prove to be more informative. This paper focuses on determining the potential of heat collection from solar radiation in asphalt solar collectors using steel piping. The asphalt solar collector model constructed for this research was prepared in the civil engineering laboratory. The hot mixed asphalt (HMA) contains 10% bitumen mixed with 90% aggregates of the total size of asphalt. Three stainless steel pipes were embedded into the interior region of the model according to the design criteria, and then put to test. Results show that harvesting energy from asphalt solar collectors proves highly potential in Malaysia due its the hot climate.

  12. Influence of anthropogenic aerosol on solar radiation in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Ten Brink, H M

    1993-12-01

    Backscatter of solar radiation by aerosol and the cooling thus induced, is the single largest uncertainty factor in assessing the climate effect of the greenhouse gases. The dominant reason for the uncertainty in the aerosol effect is its local nature. Therefore it is only via localized efforts that estimates can be improved. It is the aim of the present study to better assess the amount of solar radiation intercepted by aerosol, especially that of aerosol of anthropogenic origin in Europe. The assessment is realized along three interconnected approaches. First, empirical factors stemming from measurements in the US and used in the present estimates of the reflection of solar radiation by anthropogenic aerosol are checked for their validity in the European domain. Secondly, historical data on solar flux in Europe are related to the historic trend in aerosol loading. Finally, a sophisticated aerosol and cloud (radiation) module is developed for incorporation in a climate model. The radiation module uses aerosol characteristics as measured in the field and is validated via solar radiation measurements. The concerted investigation started in January 1993. The data obtained in the first phase of the study formed the basis for the definite detailed approach and will therefore be reported in this text. 1 fig., 9 refs.

  13. 3D radiation sensors with three dimensional electrodes

    CERN Document Server

    Da Via, Cinzia; Parker, Sherwood

    2018-01-01

    This book covers the technical properties, fabrication details, measurement results and applications of three-dimensional silicon radiation sensors. Such devices are currently used in the ATLAS experiment at the European Centre for Particle Physics (CERN) for particle tracking in high energy physics. They are the radiation hardest devices ever fabricated. They have applications in neutron detection, medical dosimetry and space. Written by the leading names in this field, the book explains to non-experts the essential features of silicon particle detectors, interactions of radiation with matter, radiation damage effects, and micro-fabrication. It also provides an historical view of the above.

  14. Increased radiation resistance in lithium-counterdoped silicon solar cells

    Science.gov (United States)

    Weinberg, I.; Swartz, C. K.; Mehta, S.

    1984-01-01

    Lithium-counterdoped n(+)p silicon solar cells are found to exhibit significantly increased radiation resistance to 1-MeV electron irradiation when compared to boron-doped n(+)p silicon solar cells. In addition to improved radiation resistance, considerable damage recovery by annealing is observed in the counterdoped cells at T less than or equal to 100 C. Deep level transient spectroscopy measurements are used to identify the defect whose removal results in the low-temperature aneal. It is suggested that the increased radiation resistance of the counterdoped cells is primarily due to interaction of the lithium with interstitial oxygen.

  15. Ways of providing radiation resistance of magnetic field semiconductor sensors

    CERN Document Server

    Bolshakova, I A; Holyaka, R; Matkovskii, A; Moroz, A

    2001-01-01

    Hall magnetic field sensors resistant to hard ionizing irradiation are being developed for operation under the radiation conditions of space and in charged particle accelerators. Radiation resistance of the sensors is first determined by the properties of semiconductor materials of sensitive elements; we have used microcrystals and thin layers of III-V semiconductors. Applying complex doping by rare-earth elements and isovalent impurities in certain proportions, we have obtained magnetic field sensors resistant to irradiation by fast neutrons and gamma-quanta. Tests of their radiation resistance were carried out at IBR-2 at the Joint Institute for Nuclear Research (Dubna). When exposed to neutrons with E=0.1-13 MeV and intensity of 10 sup 1 sup 0 n cm sup - sup 2 s sup - sup 1 , the main parameter of the sensors - their sensitivity to magnetic fields - changes by no more than 0.1% up to fluences of 10 sup 1 sup 4 n cm sup - sup 2. Further improvement of radiation resistance of sensor materials is expected by ...

  16. Fabrication of advanced military radiation detector sensor and performance evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Sin Yang

    2010-02-15

    Recently, our country is facing a continuous nuclear weapons threat. Therefore, we must have a high-level nuclear weapons protection system. The best protection against nuclear weapons is detecting their use to reduce casualties in our country to a minimum. That means, the development of a military radiation detector is a very important issue. The Korea army is using the 'PDR - 1K portable military radiation surveymeter' in NBC (Nuclear, Biological, Chemical warfare) operations. The PDR - 1K military detector can measure beta and gamma rays only but it cannot detect alpha particles. Because of its characteristics, the Korea army has weaknesses in tactical operations. The PDR - 1K sensor is based on a GM - tube sensor system. For the mechanical structure, detectors utilizing a GM-tube sensor do not work on a high - radiation battlefield and they do not carry out nuclide analysis for fixed electron signal output. In the meantime, the United States of America and Germany are using 'AN/PDR - 77' and 'SVG - 2' that were made from scintillator sensors. They have excellent physical qualities and radiation responses for military use. Also, nuclide analysis is available. Therefore, in this study we fabricated a military - grade scintillator radiation sensor that is able to detect alpha, beta, and gamma - rays to overcome PDR - 1K's weaknesses. Also, physical characteristics and radiation response evaluation for the fabricated sensors was carried out. The alpha - particle sensor and beta - ray sensor were fabricated using a ZnS(Ag) powder state scintillator, and a Saint - Gobain organic plastic scintillator BC-408 panel, respectively. The gamma ray sensor was manufactured using a 10 x 10 x 10 mm{sup 3} CsI(Tl) inorganic scintillator crystal. A detailed explanation follows. The alpha particle sensor was fabricated by using air - brushing method to Zns(Ag) powder scintillator spreading. The ZnS(Ag) layer thickness was 35 {mu}m (detection

  17. Radiator selection for Space Station Solar Dynamic Power Systems

    Science.gov (United States)

    Fleming, Mike; Hoehn, Frank

    A study was conducted to define the best radiator for heat rejection of the Space Station Solar Dynamic Power System. Included in the study were radiators for both the Organic Rankine Cycle and Closed Brayton Cycle heat engines. A number of potential approaches were considered for the Organic Rankine Cycle and a constructable radiator was chosen. Detailed optimizations of this concept were conducted resulting in a baseline for inclusion into the ORC Preliminary Design. A number of approaches were also considered for the CBC radiator. For this application a deployed pumped liquid radiator was selected which was also refined resulting in a baseline for the CBC preliminary design. This paper reports the results and methodology of these studies and describes the preliminary designs of the Space Station Solar Dynamic Power System radiators for both of the candidate heat engine cycles.

  18. Flight attendant radiation dose from solar particle events.

    Science.gov (United States)

    Anderson, Jeri L; Mertens, Christopher J; Grajewski, Barbara; Luo, Lian; Tseng, Chih-Yu; Cassinelli, Rick T

    2014-08-01

    Research has suggested that work as a flight attendant may be related to increased risk for reproductive health effects. Air cabin exposures that may influence reproductive health include radiation dose from galactic cosmic radiation and solar particle events. This paper describes the assessment of radiation dose accrued during solar particle events as part of a reproductive health study of flight attendants. Solar storm data were obtained from the National Oceanic and Atmospheric Administration Space Weather Prediction Center list of solar proton events affecting the Earth environment to ascertain storms relevant to the two study periods (1992-1996 and 1999-2001). Radiation dose from exposure to solar energetic particles was estimated using the NAIRAS model in conjunction with galactic cosmic radiation dose calculated using the CARI-6P computer program. Seven solar particle events were determined to have potential for significant radiation exposure, two in the first study period and five in the second study period, and over-lapped with 24,807 flight segments. Absorbed (and effective) flight segment doses averaged 6.5 μGy (18 μSv) and 3.1 μGy (8.3 μSv) for the first and second study periods, respectively. Maximum doses were as high as 440 μGy (1.2 mSv) and 20 flight segments had doses greater than 190 μGy (0.5 mSv). During solar particle events, a pregnant flight attendant could potentially exceed the equivalent dose limit to the conceptus of 0.5 mSv in a month recommended by the National Council on Radiation Protection and Measurements.

  19. Solar ultraviolet radiation effects on biological systems

    International Nuclear Information System (INIS)

    Diffey, B.L.

    1991-01-01

    This extensive review discusses the topic under the following headings: ultraviolet climatology, molecular and cellular ultraviolet photobiology (absorption, photoproducts, repair), effects of solar UVR on aquatic life (phyto and zooplankton), plants and humans. The section on human effects includes tanning, photo-aging, non-melanoma and melanoma skin cancers and the effects of solar UVR on the eye. (UK)

  20. Solar ultraviolet radiation effects on biological systems

    Energy Technology Data Exchange (ETDEWEB)

    Diffey, B.L. (Dryburn Hospital, Durham (UK). Regional Medical Physics Dept.)

    1991-03-01

    This extensive review discusses the topic under the following headings: ultraviolet climatology, molecular and cellular ultraviolet photobiology (absorption, photoproducts, repair), effects of solar UVR on aquatic life (phyto and zooplankton), plants and humans. The section on human effects includes tanning, photo-aging, non-melanoma and melanoma skin cancers and the effects of solar UVR on the eye. (UK).

  1. Solar wind radiation damage in lunar dust grains and the characteristics of the ancient solar wind

    International Nuclear Information System (INIS)

    Borg, J.; Chaumont, J.

    1980-01-01

    Current understanding of the exposure history of lunar dust grains to the ancient solar wind is reviewed, the work being based mostly on a Monte Carlo statistical code, describing the 'gardening' effects of the meteorite bombardment in the lunar regolith, and on analytical models, yielding the lifetimes of the grains against various types of destruction processes. Families of lunar dust grains are identified, and evidence is presented showing that lunar dust grains were not partially shielded from solar wind ions. Results of solar wind simulation experiments are used to interpret the thickness distribution of the amorphous coatings of solar wind radiation-damaged material observed on 1-micron lunar dust grains. It is argued that such distributions reflect the speed distribution of the ancient solar wind as averaged over periods of approximately 5000 years in duration, and that the ancient solar wind is less energetic than the present day solar wind

  2. Modeling Solar Radiation in the Forest Using Remote Sensing Data: A Review of Approaches and Opportunities

    Directory of Open Access Journals (Sweden)

    Alex S. Olpenda

    2018-05-01

    Full Text Available Solar radiation, the radiant energy from the sun, is a driving variable for numerous ecological, physiological, and other life-sustaining processes in the environment. Traditional methods to quantify solar radiation are done either directly (e.g., quantum sensors, or indirectly (e.g., hemispherical photography. This study, however, evaluates literature which utilized remote sensing (RS technologies to estimate various forms of solar radiation or components, thereof under or within forest canopies. Based on the review, light detection and ranging (LiDAR has, so far, been preferably used for modeling light under tree canopies. Laser system’s capability of generating 3D canopy structure at high spatial resolution makes it a reasonable choice as a source of spatial information about light condition in various parts of forest ecosystem. The majority of those using airborne laser system (ALS commonly adopted the volumetric-pixel (voxel method or the laser penetration index (LPI for modeling the radiation, while terrestrial laser system (TLS is preferred for canopy reconstruction and simulation. Furthermore, most of the studies focused only on global radiation, and very few on the diffuse fraction. It was also found out that most of these analyses were performed in the temperate zone, with a smaller number of studies made in tropical areas. Nonetheless, with the continuous advancement of technology and the RS datasets becoming more accessible and less expensive, these shortcomings and other difficulties of estimating the spatial variation of light in the forest are expected to diminish.

  3. Tritium-Powered Radiation Sensor Network

    Science.gov (United States)

    2015-09-01

    Photomultiplier Tube, Scintillator, Geiger counter, Zigbee, Wireless Network, Radiation detector, Dirty Bomb 16. SECURITY CLASSIFICATION OF: 17...operational lifetime of 150 years. Persistent sensing of the environment with vibration and radiation (electromagnetic [ EM ], acoustic, gamma, etc.) in...Transportation E-field electric field EH electron-hole EM electromagnetic GaAs gallium arsenide GPS global positioning system InGaP indium gallium

  4. Interplanetary Radiation and Internal Charging Environment Models for Solar Sails

    Science.gov (United States)

    Minow, Joseph I.; Altstatt, Richard L.; NeegaardParker, Linda

    2005-01-01

    A Solar Sail Radiation Environment (SSRE) model has been developed for defining charged particle environments over an energy range from 0.01 keV to 1 MeV for hydrogen ions, helium ions, and electrons. The SSRE model provides the free field charged particle environment required for characterizing energy deposition per unit mass, charge deposition, and dose rate dependent conductivity processes required to evaluate radiation dose and internal (bulk) charging processes in the solar sail membrane in interplanetary space. Solar wind and energetic particle measurements from instruments aboard the Ulysses spacecraft in a solar, near-polar orbit provide the particle data over a range of heliospheric latitudes used to derive the environment that can be used for radiation and charging environments for both high inclination 0.5 AU Solar Polar Imager mission and the 1.0 AU L1 solar missions. This paper describes the techniques used to model comprehensive electron, proton, and helium spectra over the range of particle energies of significance to energy and charge deposition in thin (less than 25 micrometers) solar sail materials.

  5. Radiation resistance of solar cells for space application, 1

    International Nuclear Information System (INIS)

    Mitsui, Hiroshi; Tanaka, Ryuichi; Sunaga, Hiromi

    1989-07-01

    A 50-μm thick ultrathin silicon solar cell and a 280-μm thick high performance AlGaAs/GaAs solar cell with high radiation resistance have been recently developed by National Space Development Agency of Japan (NASDA). In order to study the radiation resistance of these cells, a joint research was carried out between Japan Atomic Energy Research Institute (JAERI) and NASDA from 1984 through 1987. In this research, the irradiation method of electron beams, the effects of the irradiation conditions on the deterioration of solar cells by electron beams, and the annealing effects of the radiation damage in solar cells were investigated. This paper is the first one of a series of reports of the joint research. In this paper, the space radiation environment which artificial satellites will encounter, the solar cells used, and the experimental methods are described. In addition to these, the results of the study on the irradiation procedure of electron beams are reported. In the study of the irradiation method of electron beams, three methods, that is, the fixed irradiation method, the moving irradiation method, and the spot irradiation method were examined. In the fixed irradiation method and moving one, stationary solar cells and solar cells moving by conveyer were irradiated by scanning electron beams, respectively. On the other hand, in the spot irradiation method, stationary solar cells were irradiated by non-scanning steady electron beams. It was concluded that the fixed irradiation method was the most proper method. In addition to this, in this study, some pieces of information were obtained with respect to the changes in the electrical characteristics of solar cells caused by the irradiation of electron beams. (author) 52 refs

  6. Calibration of GOES-derived solar radiation data using a distributed network of surface measurements in Florida, USA

    Science.gov (United States)

    Sumner, David M.; Pathak, Chandra S.; Mecikalski, John R.; Paech, Simon J.; Wu, Qinglong; Sangoyomi, Taiye; Babcock, Roger W.; Walton, Raymond

    2008-01-01

    Solar radiation data are critically important for the estimation of evapotranspiration. Analysis of visible-channel data derived from Geostationary Operational Environmental Satellites (GOES) using radiative transfer modeling has been used to produce spatially- and temporally-distributed datasets of solar radiation. An extensive network of (pyranometer) surface measurements of solar radiation in the State of Florida has allowed refined calibration of a GOES-derived daily integrated radiation data product. This refinement of radiation data allowed for corrections of satellite sensor drift, satellite generational change, and consideration of the highly-variable cloudy conditions that are typical of Florida. To aid in calibration of a GOES-derived radiation product, solar radiation data for the period 1995–2004 from 58 field stations that are located throughout the State were compiled. The GOES radiation product was calibrated by way of a three-step process: 1) comparison with ground-based pyranometer measurements on clear reference days, 2) correcting for a bias related to cloud cover, and 3) deriving month-by-month bias correction factors. Pre-calibration results indicated good model performance, with a station-averaged model error of 2.2 MJ m–2 day–1 (13 percent). Calibration reduced errors to 1.7 MJ m–2 day–1 (10 percent) and also removed time- and cloudiness-related biases. The final dataset has been used to produce Statewide evapotranspiration estimates.

  7. Effect of solar radiation on drying house performance

    International Nuclear Information System (INIS)

    Rachmat, R.

    2000-01-01

    Solar drying is one of thermal utilization where radiation energy can be utilized efficiently. Solar drying of all sorts of agricultural products have been thoroughly studied and reported in literature, but brown rice drying system has not yet done as many as other products. The aim of the present study is to investigate the effect of solar radiation on drying house performance and brown rice drying characteristics. A construction of drying house is made from FRP sheets with 30 deg. of root slope faces southern part and inside the drying house is installed a flat bed dryer. The site of construction has 136 deg. 31.4'E in longitude and 34 deg. 43.8N in latitude with 3 m in elevation from sea level. The investigated parameters are global solar radiation, absorbed and net radiation and brown rice drying characteristics. The results showed that in unload condition, the air temperature inside drying house was higher (10 deg. C - 12 deg. C) than ambient air when there was not collector and temperature rise become higher (16 deg. C) when there was a black FRP collector inside drying house. The effect of solar radiation on temperature rise has the trend as a linear function. The heat collection efficiency of drying house with black FRP collector was two times higher (36.9 percent) than that without collector (16.3 percent). These phenomena exhibited significant result of collector utilization to the advantageous condition for a drying purpose [in

  8. Prediction of hourly solar radiation with multi-model framework

    International Nuclear Information System (INIS)

    Wu, Ji; Chan, Chee Keong

    2013-01-01

    Highlights: • A novel approach to predict solar radiation through the use of clustering paradigms. • Development of prediction models based on the intrinsic pattern observed in each cluster. • Prediction based on proper clustering and selection of model on current time provides better results than other methods. • Experiments were conducted on actual solar radiation data obtained from a weather station in Singapore. - Abstract: In this paper, a novel multi-model prediction framework for prediction of solar radiation is proposed. The framework started with the assumption that there are several patterns embedded in the solar radiation series. To extract the underlying pattern, the solar radiation series is first segmented into smaller subsequences, and the subsequences are further grouped into different clusters. For each cluster, an appropriate prediction model is trained. Hence a procedure for pattern identification is developed to identify the proper pattern that fits the current period. Based on this pattern, the corresponding prediction model is applied to obtain the prediction value. The prediction result of the proposed framework is then compared to other techniques. It is shown that the proposed framework provides superior performance as compared to others

  9. SRADLIB: A C Library for Solar Radiation Modelling

    Energy Technology Data Exchange (ETDEWEB)

    Balenzategui, J. L. [Ciemat. Madrid (Spain)

    2000-07-01

    This document shows the result of an exhaustive study about the theoretical and numerical models available in the literature about solar radiation modelling. The purpose of this study is to develop or adapt mathematical models describing the solar radiation specifically for Spain locations as well as to create computer tools able to support the labour of researchers or engineers needing solar radiation data to solve or improve the technical or energetic performance of solar systems. As results of this study and revision, a C library (SRADLIB) is presented as a key for the compilation of the mathematical models from different authors, for the comparison among the different approaches and for its application in computer programs. Different topics related to solar radiation and its modelling are first discussed, including the assumptions and conventions adopted and describing the most accepted and used current state-of-the-art models. some typical problems in the numerical calculation of radiation values are also posed with the proposed solution. The document includes next a complete reference of the developed functions, with many examples of application and calculus. (Author) 24 refs.

  10. SRADLIB: A C Library for Solar Radiation Modelling

    International Nuclear Information System (INIS)

    Balenzategui, J. L.

    1999-01-01

    This document shows the result of an exhaustive study about the theoretical and numerical models available in the literature about solar radiation modelling. The purpose of this study is to develop or adapt mathematical models describing the solar radiation specifically for Spain locations as well as to create computer tools able to support the labour of researchers or engineers needing solar radiation data to solve or improve the technical or energetic performance of solar systems. As result of this study and revision, a C library (SRADLIB) is presented as a key tool for the compilation of the mathematical models from different authors, for the comparison among the different approaches and for its application in computer programs. Different topics related to solar radiation and its modelling are first discussed, including the assumptions and conventions adopted and describing the most accepted and used current state-of-the-art models. Some typical problems in the numerical calculation of radiation values are also posed with the proposed solution. The document includes next a complete reference of the developed functions, with many examples of application and calculus. (Author) 24 refs

  11. Performance of semiconductor radiation sensors for simple and low-cost radiation detector

    International Nuclear Information System (INIS)

    Tanimura, Yoshihiko; Birumachi, Atsushi; Yoshida, Makoto; Watanabe, Tamaki

    2008-01-01

    In order to develop a simple but reliable radiation detector for the general public, photon detection performances of radiation sensors have been studied in photon calibration fields and by Monte Carlo simulations. A silicon p-i-n photodiode and a CdTe detector were selected for the low cost sensors. Their energy responses to ambient dose equivalent H * (10) were evaluated over the energy range from 60 keV to 2 MeV. The response of the CdTe decreases markedly with increasing photon energy. On the other hand, the photodiode has the advantage of almost flat response above 150 keV. The sensitivities of these sensors are 4 to 6 cpm for the natural radiation. Detection limits of the radiation level are low enough to know the extreme increase of radiation due to emergency situations of nuclear power plants, fuel treatment facilities and so on. (author)

  12. Solar Radiation Received by Slopes Using COMS Imagery, a Physically Based Radiation Model, and GLOBE

    Directory of Open Access Journals (Sweden)

    Jong-Min Yeom

    2016-01-01

    Full Text Available This study mapped the solar radiation received by slopes for all of Korea, including areas that are not measured by ground station measurements, through using satellites and topographical data. When estimating insolation with satellite, we used a physical model to measure the amount of hourly based solar surface insolation. Furthermore, we also considered the effects of topography using the Global Land One-Kilometer Base Elevation (GLOBE digital elevation model (DEM for the actual amount of incident solar radiation according to solar geometry. The surface insolation mapping, by integrating a physical model with the Communication, Ocean, and Meteorological Satellite (COMS Meteorological Imager (MI image, was performed through a comparative analysis with ground-based observation data (pyranometer. Original and topographically corrected solar radiation maps were created and their characteristics analyzed. Both the original and the topographically corrected solar energy resource maps captured the temporal variations in atmospheric conditions, such as the movement of seasonal rain fronts during summer. In contrast, although the original solar radiation map had a low insolation value over mountain areas with a high rate of cloudiness, the topographically corrected solar radiation map provided a better description of the actual surface geometric characteristics.

  13. Increase of solar radiation due to climate change and its impact on solar energy use

    International Nuclear Information System (INIS)

    Kuhnke, K.; Rahme, A.; Harling, J.; Arensmann, R.

    2008-01-01

    Full text: There is a significant change in solar radiation in Central Europe coinciding with the IPCC climate change model calculations. The increase of yearly solar radiation on the horizontal surface is about 0.38 percent/year. On the other hand, photovoltaic solar modules show an ageing effect of the same order of magnitude, i.e. a reduction of yearly energy yield between 0.3 and 0.5 percent/year. This reduction is normally taken into account in economic calculations such as payback time and internal rate of interest. As the two trends of increase in radiation and ageing of solar modules are in opposite direction to each other, they will - with their uncertainties - neutralize one another to zero. Thus, the energy production of photovoltaic systems can be calculated without any deductions due to ageing in the future. (authors)

  14. Measuring Solar Radiation Incident on Earth: Solar Constant-3 (SOLCON-3)

    Science.gov (United States)

    Crommelynck, Dominique; Joukoff, Alexandre; Dewitte, Steven

    2002-01-01

    Life on Earth is possible because the climate conditions on Earth are relatively mild. One element of the climate on Earth, the temperature, is determined by the heat exchanges between the Earth and its surroundings, outer space. The heat exchanges take place in the form of electromagnetic radiation. The Earth gains energy because it absorbs solar radiation, and it loses energy because it emits thermal infrared radiation to cold space. The heat exchanges are in balance: the heat gained by the Earth through solar radiation equals the heat lost through thermal radiation. When the balance is perturbed, a temperature change and hence a climate change of the Earth will occur. One possible perturbation of the balance is the CO2 greenhouse effect: when the amount of CO2 in the atmosphere increases, this will reduce the loss of thermal infrared radiation to cold space. Earth will gain more heat and hence the temperature will rise. Another perturbation of the balance can occur through variation of the amount of energy emitted by the sun. When the sun emits more energy, this will directly cause a rise of temperature on Earth. For a long time scientists believed that the energy emitted by the sun was constant. The 'solar constant' is defined as the amount of solar energy received per unit surface at a distance of one astronomical unit (the average distance of Earth's orbit) from the sun. Accurate measurements of the variations of the solar constant have been made since 1978. From these we know that the solar constant varies approximately with the 11-year solar cycle observed in other solar phenomena, such as the occurrence of sunspots, dark spots that are sometimes visible on the solar surface. When a sunspot occurs on the sun, since the spot is dark, the radiation (light) emitted by the sun drops instantaneously. Oddly, periods of high solar activity, when a lot of sunspot numbers increase, correspond to periods when the average solar constant is high. This indicates that

  15. Solar radiation pressure and deviations from Keplerian orbits

    Energy Technology Data Exchange (ETDEWEB)

    Kezerashvili, Roman Ya. [Physics Department, New York City College of Technology, the City University of New York, Brooklyn, NY 11201 (United States); Vazquez-Poritz, Justin F. [Physics Department, New York City College of Technology, City University of New York, Brooklyn, NY 11201 (United States)], E-mail: jporitz@gmail.com

    2009-05-04

    Newtonian gravity and general relativity give exactly the same expression for the period of an object in circular orbit around a static central mass. However, when the effects of the curvature of spacetime and solar radiation pressure are considered simultaneously for a solar sail propelled satellite, there is a deviation from Kepler's third law. It is shown that solar radiation pressure affects the period of this satellite in two ways: by effectively decreasing the solar mass, thereby increasing the period, and by enhancing the effects of other phenomena, potentially rendering some of them detectable. In particular, we consider deviations from Keplerian orbits due to spacetime curvature, frame dragging from the rotation of the sun, the oblateness of the sun, a possible net electric charge of the sun, and a very small positive cosmological constant.

  16. A review of nanostructured based radiation sensors for neutron

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Pervaiz; Mohamed, Norani Muti; Burhanudin, Zainal Arif [Center of Excellence in Nanotechnology Department of Fundamental and Applied Sciences, Department of Electrical and Electronic Engineering Universiti Teknologi PETRONAS (Malaysia)

    2012-09-26

    Currently radiation sensors with various mechanisms such as radio thermo luminescence, radiographic and radiochromic film, semiconductor and ionization have been used for the detection of nuclear radiation. Sensitivity, handling procedure, heating condition, energy response, nonlinearity, polarization, non-uniform electric field, high bias voltage and spatial resolution due to large physical size are some of the key issues faced by these sensors. Due to the excellent electrical and mechanical properties, nanostructured materials such as carbon nanotubes (CNTs) have been researched as sensing elements in the sensors to overcome the mentioned problems. However CNTs are found to pose different problems, arising from the uncontrolled helicity and small cross-sectional area. Therefore, alternative sensing elements are still been sought after and the possibility of using boron nitride nanotubes for sensing neutron is considered in this review.

  17. Solar panel thermal cycling testing by solar simulation and infrared radiation methods

    Science.gov (United States)

    Nuss, H. E.

    1980-01-01

    For the solar panels of the European Space Agency (ESA) satellites OTS/MAROTS and ECS/MARECS the thermal cycling tests were performed by using solar simulation methods. The performance data of two different solar simulators used and the thermal test results are described. The solar simulation thermal cycling tests for the ECS/MARECS solar panels were carried out with the aid of a rotatable multipanel test rig by which simultaneous testing of three solar panels was possible. As an alternative thermal test method, the capability of an infrared radiation method was studied and infrared simulation tests for the ultralight panel and the INTELSAT 5 solar panels were performed. The setup and the characteristics of the infrared radiation unit using a quartz lamp array of approx. 15 sq and LN2-cooled shutter and the thermal test results are presented. The irradiation uniformity, the solar panel temperature distribution, temperature changing rates for both test methods are compared. Results indicate the infrared simulation is an effective solar panel thermal testing method.

  18. Methodology and measurement of radiation interception by quantum sensor of the oil palm plantation

    Directory of Open Access Journals (Sweden)

    Johari Endan

    2005-09-01

    Full Text Available Interception of light by a canopy is a fundamental requirement for crop growth and is important for biomass production and plant growth modeling. Solar radiation is an important parameter for photosynthesis and evapotranspiration. These two phenomena are dependent not only on the intensity of radiation but also on the distribution of intercepted radiation within the canopy. In this study, two operational methods for estimating the amount of photosynthetically active radiation (PAR intercepted by a canopy of the oil palm are presented. LICOR radiation sensors, model LI-190SA and model LI-191SA were used for photosynthetically active radiation (PAR measurement above and below the canopy. We developed two methods, namely "Triangular" method and "Circular" method for PAR measurement. Results show that both methods were suitable for oil palm PAR measurement. The triangular method is recommended for PAR measurements with respect to the whole plantation and the circular method is recommended for specific purposes, such as growth analysis or growth modeling of the oil palm. However, practical considerations such as equipment availability, purpose of the measurement, age of the palm, and the number of measuring points to be sampled should be taken into account in the selection of a suitable method for a particular study. The results indicate that the interception of radiation was affected by spatial variation, and the radiation transmission decreased towards the frond tips.

  19. Global Solar Radiation in Spain from Satellite Images

    International Nuclear Information System (INIS)

    Ramirez, L.; Mora, L.; Sidrach de Cardona, M.; Navarro, A. A.; Varela, M.; Cruz, M. de la

    2003-01-01

    In the context of the present work a series of algorithms of calculation of the solar radiation from satellite images has been developed. These models, have been applied to three years of images of the Meteosat satellite and the results of the treatment have been extrapolated to long term. For the development of the models of solar radiation registered in ground stations have been used, corresponding all of them to localities of peninsular Spain and the Balearic ones. The maximum periods of data available have been used, supposing in most of the cases periods of between 6 and 9 years. From the results has a year type of images of global solar radiation on horizontal surface. The original resolution of the image of 7x7 km in the study latitudes, has been reevaluated to 5x5 km. This supposes to have a value of the typical radiation for every day of the year, each 5x5 km in the study territory. This information, supposes an important advance as far as the knowledge of the space distribution of the radiation solar, impossible to reach about alternative methods. Doubtlessly, the precision of the provided values is not comparable with pyrano metric measures in a concrete locality, but it provides a very valid indicator in places in which it is not had previous information. In addition to the radiation maps, tables of the global solar radiation have been prepared on different inclinations, from the global radiation on horizontal surface calculated for every day of the year and in each pixel of the image. (Author) 24 refs

  20. Atmospheric Renewable Energy Research, Volume 5 (Solar Radiation Flux Model)

    Science.gov (United States)

    2017-09-01

    sources, namely photovoltaic (PV) panels, to roughly determine the energy producing potential of an installation’s solar array. The implicit...power resources assembled as a single system (generator, storage, distribution and load), with the ability to run independently as an “island” and/or...atmospheric layers that will act on the solar radiation as it traverses strata. These terms are a function of cloud type, size , and density. To create a

  1. Curve fitting methods for solar radiation data modeling

    Energy Technology Data Exchange (ETDEWEB)

    Karim, Samsul Ariffin Abdul, E-mail: samsul-ariffin@petronas.com.my, E-mail: balbir@petronas.com.my; Singh, Balbir Singh Mahinder, E-mail: samsul-ariffin@petronas.com.my, E-mail: balbir@petronas.com.my [Department of Fundamental and Applied Sciences, Faculty of Sciences and Information Technology, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak Darul Ridzuan (Malaysia)

    2014-10-24

    This paper studies the use of several type of curve fitting method to smooth the global solar radiation data. After the data have been fitted by using curve fitting method, the mathematical model of global solar radiation will be developed. The error measurement was calculated by using goodness-fit statistics such as root mean square error (RMSE) and the value of R{sup 2}. The best fitting methods will be used as a starting point for the construction of mathematical modeling of solar radiation received in Universiti Teknologi PETRONAS (UTP) Malaysia. Numerical results indicated that Gaussian fitting and sine fitting (both with two terms) gives better results as compare with the other fitting methods.

  2. Curve fitting methods for solar radiation data modeling

    Science.gov (United States)

    Karim, Samsul Ariffin Abdul; Singh, Balbir Singh Mahinder

    2014-10-01

    This paper studies the use of several type of curve fitting method to smooth the global solar radiation data. After the data have been fitted by using curve fitting method, the mathematical model of global solar radiation will be developed. The error measurement was calculated by using goodness-fit statistics such as root mean square error (RMSE) and the value of R2. The best fitting methods will be used as a starting point for the construction of mathematical modeling of solar radiation received in Universiti Teknologi PETRONAS (UTP) Malaysia. Numerical results indicated that Gaussian fitting and sine fitting (both with two terms) gives better results as compare with the other fitting methods.

  3. Curve fitting methods for solar radiation data modeling

    International Nuclear Information System (INIS)

    Karim, Samsul Ariffin Abdul; Singh, Balbir Singh Mahinder

    2014-01-01

    This paper studies the use of several type of curve fitting method to smooth the global solar radiation data. After the data have been fitted by using curve fitting method, the mathematical model of global solar radiation will be developed. The error measurement was calculated by using goodness-fit statistics such as root mean square error (RMSE) and the value of R 2 . The best fitting methods will be used as a starting point for the construction of mathematical modeling of solar radiation received in Universiti Teknologi PETRONAS (UTP) Malaysia. Numerical results indicated that Gaussian fitting and sine fitting (both with two terms) gives better results as compare with the other fitting methods

  4. CMOS front-end electronics for radiation sensors

    CERN Document Server

    AUTHOR|(CDS)2071026

    2015-01-01

    This book offers a comprehensive treatment of front-end electronics for radiation detection. It discusses the fundamental principles of signal processing for radiation detectors and describes circuits at the level of functional building blocks, omitting transistor-level implementation. It also covers important system-level topics commonly found in the world of front-end electronics for radiation sensors. The book develops the topics in detail, with a constant focus on practical problems. It also provides real implementation examples that offer insights and stimuli for more experienced engineers already working in the field.

  5. Estimation of solar radiation from Australian meterological observations

    International Nuclear Information System (INIS)

    Moriarty, W.W.

    1991-01-01

    A carefully prepared set of Australian radiation and meteorological data was used to develop a system for estimating hourly or instantaneous broad band direct, diffuse and global radiation from meteorological observations. For clear sky conditions relationships developed elsewhere were adapted to Australian data. For cloudy conditions the clouds were divided into two groups, high clouds and opaque (middle and low) clouds, and corrections were made to compensate for the bias due to reporting practices for almost clear and almost overcast skies. Careful consideration was given to the decrease of visible sky toward the horizon caused by the vertical extent of opaque clouds. Equations relating cloud and other meteorological observations to the direct and diffuse radiation contained four unknown quantities, functions of cloud amount and of solar elevation, which were estimated from the data. These were the proportions of incident solar radiation passed on as direct and as diffuse radiation by high clouds, and as diffuse radiation by opaque clouds, and a factor to describe the elevation dependence of the fraction of sky not obscured by opaque clouds. When the resulting relationships were used to estimate global, direct and diffuse radiation on a horizontal surface, the results were good, especially for global radiation. Some discrepancies between estimates and measurements of diffuse and direct radiation were probably due to erroneously high measurements of diffuse radiation

  6. Solar Radiation effect on the bituminous binder; Efecto de la radiacion solar sobre el ligante bituminoso

    Energy Technology Data Exchange (ETDEWEB)

    Tadeo Rico, A.; Torres Perez, A.

    2010-07-01

    Asphalt, used as binder in road construction, becomes more brittle and harder during working life on the surface of the road pavement, conducting toward their deterioration. This is caused by the oxidation of the molecular functional groups of the asphalt molecular structure. Moreover, it is observed that ultraviolet radiation increases the oxidation process. However, the effect of solar light on the asphalt degradation has been poorly researched. The aim of this work is to study asphalt ageing caused by effect of solar radiation, by using standard test. Four commercial asphalts from different companies were selected: two with penetration number 50/70, and the other two polymer modified asphalts. From each of the asphalts forty samples were taken off and placed in four different aging conditions of temperature and radiation for a period ranging from 40 to 500 days. Ring and Ball test, and Fraass breaking Point test, were used to analyse the changes of asphalt properties after exposition to solar radiation. The results of the four analyzed asphalts showed a distinct behaviour; not only in the test temperature increase but also in the rate. Another experiment was carried out. Samples from a hot mix asphalt batch were placed under solar radiation, and were compacted by the Marshall procedure after increasing periods of time. Density and resistance to plastic flow using Marshall Apparatus were measured. Results showed an increase in the stability of samples under radiation. Both experiments show that the solar radiation is enough to cause changes in the asphalt molecular structure due to oxidation. So that, the study of the effect of the solar radiation on the asphalt properties could be a good tool to asses the performances of asphalt pavement. (Author) 26 refs.

  7. Fabrication and a Study on the Tapered Scintillator Radiation Sensors

    International Nuclear Information System (INIS)

    Kim, Gye Hong

    2003-02-01

    Optical fibers have been investigated for their uses as sensor materials in various nuclear applications. Comprehensive overviews of their potential usages in nuclear environments can be found in the literatures. Optical fibers with doped scintillating elements in the core have drawn special interests as nuclear radiation detectors. The two important functions of a scintillating optical fiber, as a radiation detector, are scintillator (light emitter) and light transmitter. When radiation interacts with the core material, scintillation occurs and resultant lights are transmitted through the fiber to an opto-electronic device such as a photomultiplier tube. Optical fiber sensors have several advantages as compared to other sensors of conventional material. Since they do not require electric power in the sensor part, they are less susceptible to trouble in harsh environments such as underground or underwater. At relatively low cost a multi-point distributed radiation monitoring system could be made using the fiber sensors. Furthermore, unlike the conventional scintillating counters they are not influenced by any magnetic field surrounding them. This study has been conducted to investigate the feasibility of using scintillating optical fibers for the detection of gamma rays emitted by 137 Cs. Several types of gamma-ray sensors have been constructed by packing different numbers of fibers into aluminum tubes, and tested to detect the 137 Cs gamma ray. During the study it has been found that a tapered fibers might be more efficient to collect the lights produced inside the sensor and transfer them into the transmitting fiber. In order to investigate the effectiveness of the tapered fiber, tapered plastic scintillators, composed of polystyrene with minute amount of dPOPOP and PPO or bPBD, have been fabricated and tested for the detection of gamma rays from 1.0, 1.5, 3.0 and 5.0 μCi 137 Cs sources. The pulse height spectra and the relationship between the radioactivity and

  8. Characterisation of a smartphone image sensor response to direct solar 305nm irradiation at high air masses.

    Science.gov (United States)

    Igoe, D P; Amar, A; Parisi, A V; Turner, J

    2017-06-01

    This research reports the first time the sensitivity, properties and response of a smartphone image sensor that has been used to characterise the photobiologically important direct UVB solar irradiances at 305nm in clear sky conditions at high air masses. Solar images taken from Autumn to Spring were analysed using a custom Python script, written to develop and apply an adaptive threshold to mitigate the effects of both noise and hot-pixel aberrations in the images. The images were taken in an unobstructed area, observing from a solar zenith angle as high as 84° (air mass=9.6) to local solar maximum (up to a solar zenith angle of 23°) to fully develop the calibration model in temperatures that varied from 2°C to 24°C. The mean ozone thickness throughout all observations was 281±18 DU (to 2 standard deviations). A Langley Plot was used to confirm that there were constant atmospheric conditions throughout the observations. The quadratic calibration model developed has a strong correlation between the red colour channel from the smartphone with the Microtops measurements of the direct sun 305nm UV, with a coefficient of determination of 0.998 and very low standard errors. Validation of the model verified the robustness of the method and the model, with an average discrepancy of only 5% between smartphone derived and Microtops observed direct solar irradiances at 305nm. The results demonstrate the effectiveness of using the smartphone image sensor as a means to measure photobiologically important solar UVB radiation. The use of ubiquitous portable technologies, such as smartphones and laptop computers to perform data collection and analysis of solar UVB observations is an example of how scientific investigations can be performed by citizen science based individuals and groups, communities and schools. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Missing Data Imputation of Solar Radiation Data under Different Atmospheric Conditions

    Science.gov (United States)

    Turrado, Concepción Crespo; López, María del Carmen Meizoso; Lasheras, Fernando Sánchez; Gómez, Benigno Antonio Rodríguez; Rollé, José Luis Calvo; de Cos Juez, Francisco Javier

    2014-01-01

    Global solar broadband irradiance on a planar surface is measured at weather stations by pyranometers. In the case of the present research, solar radiation values from nine meteorological stations of the MeteoGalicia real-time observational network, captured and stored every ten minutes, are considered. In this kind of record, the lack of data and/or the presence of wrong values adversely affects any time series study. Consequently, when this occurs, a data imputation process must be performed in order to replace missing data with estimated values. This paper aims to evaluate the multivariate imputation of ten-minute scale data by means of the chained equations method (MICE). This method allows the network itself to impute the missing or wrong data of a solar radiation sensor, by using either all or just a group of the measurements of the remaining sensors. Very good results have been obtained with the MICE method in comparison with other methods employed in this field such as Inverse Distance Weighting (IDW) and Multiple Linear Regression (MLR). The average RMSE value of the predictions for the MICE algorithm was 13.37% while that for the MLR it was 28.19%, and 31.68% for the IDW. PMID:25356644

  10. Missing Data Imputation of Solar Radiation Data under Different Atmospheric Conditions

    Directory of Open Access Journals (Sweden)

    Concepción Crespo Turrado

    2014-10-01

    Full Text Available Global solar broadband irradiance on a planar surface is measured at weather stations by pyranometers. In the case of the present research, solar radiation values from nine meteorological stations of the MeteoGalicia real-time observational network, captured and stored every ten minutes, are considered. In this kind of record, the lack of data and/or the presence of wrong values adversely affects any time series study. Consequently, when this occurs, a data imputation process must be performed in order to replace missing data with estimated values. This paper aims to evaluate the multivariate imputation of ten-minute scale data by means of the chained equations method (MICE. This method allows the network itself to impute the missing or wrong data of a solar radiation sensor, by using either all or just a group of the measurements of the remaining sensors. Very good results have been obtained with the MICE method in comparison with other methods employed in this field such as Inverse Distance Weighting (IDW and Multiple Linear Regression (MLR. The average RMSE value of the predictions for the MICE algorithm was 13.37% while that for the MLR it was 28.19%, and 31.68% for the IDW.

  11. Missing data imputation of solar radiation data under different atmospheric conditions.

    Science.gov (United States)

    Turrado, Concepción Crespo; López, María Del Carmen Meizoso; Lasheras, Fernando Sánchez; Gómez, Benigno Antonio Rodríguez; Rollé, José Luis Calvo; Juez, Francisco Javier de Cos

    2014-10-29

    Global solar broadband irradiance on a planar surface is measured at weather stations by pyranometers. In the case of the present research, solar radiation values from nine meteorological stations of the MeteoGalicia real-time observational network, captured and stored every ten minutes, are considered. In this kind of record, the lack of data and/or the presence of wrong values adversely affects any time series study. Consequently, when this occurs, a data imputation process must be performed in order to replace missing data with estimated values. This paper aims to evaluate the multivariate imputation of ten-minute scale data by means of the chained equations method (MICE). This method allows the network itself to impute the missing or wrong data of a solar radiation sensor, by using either all or just a group of the measurements of the remaining sensors. Very good results have been obtained with the MICE method in comparison with other methods employed in this field such as Inverse Distance Weighting (IDW) and Multiple Linear Regression (MLR). The average RMSE value of the predictions for the MICE algorithm was 13.37% while that for the MLR it was 28.19%, and 31.68% for the IDW.

  12. Using a Fuzzy Light Sensor to Improve the Efficiency of Solar Panels

    Science.gov (United States)

    Suryono; Suseno, Jatmiko Endro; Sulistiati, Ainie Khuriati Riza; Prahara, Tahan

    2018-02-01

    Solar panel efficiency can be increased by improving the quality of photovoltaic material, the effectiveness of electronic circuit, and the light source tracking model. This research is aimed at improving the quality of solar panels by tracking light source using a fuzzy logic sensor. A fuzzy light sensor property is obtained from two LDR (light dependent resistor) light sensors installed in parallel to each other and is given a light separator in between them. Both sensors are mounted on a solar panel. Sensor output is acquired using a 12 bit ADC from an ATSAM3XE microcontroller and is then sent to a computer using WIFI radio. A PID (Proportional-Integral-Derivative) control algorithm is used to manage the position of the solar panel in line with the input given by the fuzzy light sensor. This control mechanism works based on the margin of fuzzy membership from both sensors that is used to move a motor DC that in turn moves the solar panel. Experimental results show a characteristically symmetrical fuzzy membership of both sensors with a reflected correlation of R=0.9981 after gains from both sensors are arranged with a program. Upon being tested in the field, this system was capable of improving the performance of solar panels in gaining power compared to their original fixed position. The discrepancy was evident when the angle of incoming sunlight approached both 0° and 180°. Further calculations of data acquired by the fuzzy light sensor show increased solar panel power efficiency by up to 5.6%.

  13. The enerMENA meteorological network - Solar radiation measurements in the MENA region

    Science.gov (United States)

    Schüler, D.; Wilbert, S.; Geuder, N.; Affolter, R.; Wolfertstetter, F.; Prahl, C.; Röger, M.; Schroedter-Homscheidt, M.; Abdellatif, G.; Guizani, A. Allah; Balghouthi, M.; Khalil, A.; Mezrhab, A.; Al-Salaymeh, A.; Yassaa, N.; Chellali, F.; Draou, D.; Blanc, P.; Dubranna, J.; Sabry, O. M. K.

    2016-05-01

    For solar resource assessment of solar power plants and adjustment of satellite data, high accuracy measurement data of irradiance and ancillary meteorological data is needed. For the MENA region (Middle East and Northern Africa), which is of high importance for concentrating solar power applications, so far merely 2 publicly available ground measurement stations existed (BSRN network). This gap has been filled by ten stations in Morocco, Algeria, Tunisia, Egypt and Jordan. In this publication the data quality is analyzed by evaluating data completeness and the cleanliness of irradiance sensors in comparison for all of the stations. The pyrheliometers have an average cleanliness of 99.2 % for week-daily cleaning. This is a 5 times higher effort than for Rotating Shadowband Irradiometer (RSI) stations which even have a slightly higher average cleanliness of 99.3 % for weekly cleaning. Furthermore, RSI stations show a data completeness of 99.4 % compared to 93.6 % at the stations equipped with thermal sensors. The results of this analysis are used to derive conclusions concerning instrument choice and are hence also applicable to other solar radiation measurements outside the enerMENA network. It turns out that RSIs are the more reliable and robust choice in cases of high soiling, rare station visits for cleaning and maintenance, as usual in desert sites. Furthermore, annual direct normal and global horizontal irradiation as well as average meteorological parameters are calculated for all of the stations.

  14. Radiation aspects on the Earth's surface during solar flares

    International Nuclear Information System (INIS)

    Mansurov, K.Zh.; Aitmukhambetov, A.A.

    2002-01-01

    In the paper the results of investigation of radiation solution in the space near the Earth at the different altitudes of the Earth atmosphere and at the ground level in dependence on geo-coordinates and solar activity during 1957-1999 are presented. Radiation is due to the Galactic cosmic ray flux for different periods of the Solar activity: - the radiation doses of the radioactive clouds at latitudes ∼12-13 km which go ground the Earth two or three times were created; - it seems to years that these clouds make a certain contribution to the ecological situation in the Earth atmosphere and on the surface. The radiation near ground level of the Earth for the last 1500 years was calculated also using the data of radioactive carbon 14 C intensity investigation

  15. Studies of diffuse and direct solar radiation over snow

    International Nuclear Information System (INIS)

    Wesely, M.L.; Everett, R.G.

    1976-01-01

    Two interesting questions can be addressed by examination of solar radiation records obtained while the surface is covered with snow. One concerns the extent to which airborne particulate matter affects solar radiation received at the surface during winter conditions that are typical of those in the northeastern quarter of the United States. The other relates to the importance of complicated light scatterng in the earth-atmosphere system when the surface albedo is large. With the snow surface reflecting 50% or more of the incident radiation, it is likely that a significant addition to diffuse radiation would result from light that is reflected from the surface and then scattered back to the earth by the atmosphere. Preliminary data from measurements made during the winter of 1975 to 1976 are reported

  16. Solar Rotational Periodicities and the Semiannual Variation in the Solar Wind, Radiation Belt, and Aurora

    Science.gov (United States)

    Emery, Barbara A.; Richardson, Ian G.; Evans, David S.; Rich, Frederick J.; Wilson, Gordon R.

    2011-01-01

    The behavior of a number of solar wind, radiation belt, auroral and geomagnetic parameters is examined during the recent extended solar minimum and previous solar cycles, covering the period from January 1972 to July 2010. This period includes most of the solar minimum between Cycles 23 and 24, which was more extended than recent solar minima, with historically low values of most of these parameters in 2009. Solar rotational periodicities from S to 27 days were found from daily averages over 81 days for the parameters. There were very strong 9-day periodicities in many variables in 2005 -2008, triggered by recurring corotating high-speed streams (HSS). All rotational amplitudes were relatively large in the descending and early minimum phases of the solar cycle, when HSS are the predominant solar wind structures. There were minima in the amplitudes of all solar rotational periodicities near the end of each solar minimum, as well as at the start of the reversal of the solar magnetic field polarity at solar maximum (approx.1980, approx.1990, and approx. 2001) when the occurrence frequency of HSS is relatively low. Semiannual equinoctial periodicities, which were relatively strong in the 1995-1997 solar minimum, were found to be primarily the result of the changing amplitudes of the 13.5- and 27-day periodicities, where 13.5-day amplitudes were better correlated with heliospheric daily observations and 27-day amplitudes correlated better with Earth-based daily observations. The equinoctial rotational amplitudes of the Earth-based parameters were probably enhanced by a combination of the Russell-McPherron effect and a reduction in the solar wind-magnetosphere coupling efficiency during solstices. The rotational amplitudes were cross-correlated with each other, where the 27 -day amplitudes showed some of the weakest cross-correlations. The rotational amplitudes of the > 2 MeV radiation belt electron number fluxes were progressively weaker from 27- to 5-day periods

  17. First tests of a novel radiation hard CMOS sensor process for Depleted Monolithic Active Pixel Sensors

    Science.gov (United States)

    Pernegger, H.; Bates, R.; Buttar, C.; Dalla, M.; van Hoorne, J. W.; Kugathasan, T.; Maneuski, D.; Musa, L.; Riedler, P.; Riegel, C.; Sbarra, C.; Schaefer, D.; Schioppa, E. J.; Snoeys, W.

    2017-06-01

    The upgrade of the ATLAS [1] tracking detector for the High-Luminosity Large Hadron Collider (LHC) at CERN requires novel radiation hard silicon sensor technologies. Significant effort has been put into the development of monolithic CMOS sensors but it has been a challenge to combine a low capacitance of the sensing node with full depletion of the sensitive layer. Low capacitance brings low analog power. Depletion of the sensitive layer causes the signal charge to be collected by drift sufficiently fast to separate hits from consecutive bunch crossings (25 ns at the LHC) and to avoid losing the charge by trapping. This paper focuses on the characterization of charge collection properties and detection efficiency of prototype sensors originally designed in the framework of the ALICE Inner Tracking System (ITS) upgrade [2]. The prototypes are fabricated both in the standard TowerJazz 180nm CMOS imager process [3] and in an innovative modification of this process developed in collaboration with the foundry, aimed to fully deplete the sensitive epitaxial layer and enhance the tolerance to non-ionizing energy loss. Sensors fabricated in standard and modified process variants were characterized using radioactive sources, focused X-ray beam and test beams before and after irradiation. Contrary to sensors manufactured in the standard process, sensors from the modified process remain fully functional even after a dose of 1015neq/cm2, which is the the expected NIEL radiation fluence for the outer pixel layers in the future ATLAS Inner Tracker (ITk) [4].

  18. Radiation detection and situation management by distributed sensor networks

    International Nuclear Information System (INIS)

    Jan, Frigo; Mielke, Angela; Cai, D. Michael

    2009-01-01

    Detection of radioactive materials in an urban environment usually requires large, portal-monitor-style radiation detectors. However, this may not be a practical solution in many transport scenarios. Alternatively, a distributed sensor network (DSN) could complement portal-style detection of radiological materials through the implementation of arrays of low cost, small heterogeneous sensors with the ability to detect the presence of radioactive materials in a moving vehicle over a specific region. In this paper, we report on the use of a heterogeneous, wireless, distributed sensor network for traffic monitoring in a field demonstration. Through wireless communications, the energy spectra from different radiation detectors are combined to improve the detection confidence. In addition, the DSN exploits other sensor technologies and algorithms to provide additional information about the vehicle, such as its speed, location, class (e.g. car, truck), and license plate number. The sensors are in-situ and data is processed in real-time at each node. Relevant information from each node is sent to a base station computer which is used to assess the movement of radioactive materials

  19. Radiative magnetohydrodynamic simulations of solar pores

    NARCIS (Netherlands)

    Cameron, R.; Schuessler, M.; Vögler, A.; Zakharov, V.

    2007-01-01

    Context. Solar pores represent a class of magnetic structures intermediate between small-scale magnetic flux concentrations in intergranular lanes and fully developed sunspots with penumbrae. Aims. We study the structure, energetics, and internal dynamics of pore-like magnetic structures by means of

  20. Lessons learned on solar powered wireless sensor network deployments in urban, desert environments

    KAUST Repository

    Dehwah, Ahmad H.; Mousa, Mustafa; Claudel, Christian G.

    2015-01-01

    The successful deployment of a large scale solar powered wireless sensor network in an urban, desert environment is a very complex task. Specific cities of such environments cause a variety of operational problems, ranging from hardware faults

  1. Inconing solar radiation estimates at terrestrial surface using meteorological satellite

    International Nuclear Information System (INIS)

    Arai, N.; Almeida, F.C. de.

    1982-11-01

    By using the digital images of the visible channel of the GOES-5 meteorological satellite, and a simple radiative transfer model of the earth's atmosphere, the incoming solar radiation reaching ground is estimated. A model incorporating the effects of Rayleigh scattering and water vapor absorption, the latter parameterized using the surface dew point temperature value, is used. Comparisons with pyranometer observations, and parameterization versus radiosonde water vapor absorption calculation are presented. (Author) [pt

  2. A novel sensor array for field based ocular ultraviolet radiation measurements

    International Nuclear Information System (INIS)

    Fleming, D. P.; Walsh, J. E.; Moore, L. A.; Bergmanson, J. P.; McMahon, D.

    2006-01-01

    The intensification of terrestrial solar ultraviolet radiation (UVR) due to the diminution of the ozone layer has promoted a variety of research into establishing the impact of this elevated potential dose of UVR on biological tissues. Certain anterior ocular tissues have been found to be susceptible to damage by incident UVR and potentially blinding diseases such as pterygium are thought to be a direct result of absorbed UVR at the nasal limbus. There is a need for more accurate quantification and localisation of incident UVR at the anterior ocular surface. A novel solar blind photodiode sensor array system has been designed, constructed and tested for this purpose. Initial measurements to quantify the irradiance across the anterior ocular surface within the latitudes known as the 'pterygium belt' provide us with a set of core data for different head orientations and tilt angles and indicate the accuracy and stability of the system. (authors)

  3. PSA Solar furnace: A facility for testing PV cells under concentrated solar radiation

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Reche, J.; Canadas, I.; Sanchez, M.; Ballestrin, J.; Yebra, L.; Monterreal, R.; Rodriguez, J.; Garcia, G. [Concentration Solar Technologies, Plataforma Solar de Almeria-CIEMAT P.O. Box 22, Tabernas, E-04200 (Almeria) (Spain); Alonso, M.; Chenlo, F. [Photovoltaic Components and Systems, Renewable Energies Department-CIEMAT Avda. Complutense, 22, Madrid, E-28040 (Spain)

    2006-09-22

    The Plataforma Solar de Almeria (PSA), the largest centre for research, development and testing of concentration solar thermal technologies in Europe, has started to apply its knowledge, facilities and resources to development of the Concentration PV technology in an EU-funded project HiConPV. A facility for testing PV cells under solar radiation concentrated up to 2000x has recently been completed. The advantages of this facility are that, since it is illuminated by solar radiation, it is possible to obtain the appropriate cell spectral response directly, and the flash tests can be combined with prolonged PV-cell irradiation on large surfaces (up to 150cm{sup 2}), so the thermal response of the PV cell can be evaluated simultaneously. (author)

  4. Solar radiation modeling and measurements for renewable energy applications: data and model quality

    International Nuclear Information System (INIS)

    Myers, Daryl R.

    2005-01-01

    Measurement and modeling of broadband and spectral terrestrial solar radiation is important for the evaluation and deployment of solar renewable energy systems. We discuss recent developments in the calibration of broadband solar radiometric instrumentation and improving broadband solar radiation measurement accuracy. An improved diffuse sky reference and radiometer calibration and characterization software for outdoor pyranometer calibrations are outlined. Several broadband solar radiation model approaches, including some developed at the National Renewable Energy Laboratory, for estimating direct beam, total hemispherical and diffuse sky radiation are briefly reviewed. The latter include the Bird clear sky model for global, direct beam, and diffuse terrestrial solar radiation; the Direct Insolation Simulation Code (DISC) for estimating direct beam radiation from global measurements; and the METSTAT (Meteorological and Statistical) and Climatological Solar Radiation (CSR) models that estimate solar radiation from meteorological data. We conclude that currently the best model uncertainties are representative of the uncertainty in measured data

  5. Solar radiation modeling and measurements for renewable energy applications: data and model quality

    Energy Technology Data Exchange (ETDEWEB)

    Myers, D.R. [National Renewable Energy Laboratory, Golden, CO (United States)

    2005-07-01

    Measurement and modeling of broadband and spectral terrestrial solar radiation is important for the evaluation and deployment of solar renewable energy systems. We discuss recent developments in the calibration of broadband solar radiometric instrumentation and improving broadband solar radiation measurement accuracy. An improved diffuse sky reference and radiometer calibration and characterization software for outdoor pyranometer calibrations are outlined. Several broadband solar radiation model approaches, including some developed at the National Renewable Energy Laboratory, for estimating direct beam, total hemispherical and diffuse sky radiation are briefly reviewed. The latter include the Bird clear sky model for global, direct beam, and diffuse terrestrial solar radiation; the Direct Insolation Simulation Code (DISC) for estimating direct beam radiation from global measurements; and the METSTAT (Meteorological and Statistical) and Climatological Solar Radiation (CSR) models that estimate solar radiation from meteorological data. We conclude that currently the best model uncertainties are representative of the uncertainty in measured data. (author)

  6. Applications of Elpasolites as a Multimode Radiation Sensor

    Science.gov (United States)

    Guckes, Amber

    This study consists of both computational and experimental investigations. The computational results enabled detector design selections and confirmed experimental results. The experimental results determined that the CLYC scintillation detector can be applied as a functional and field-deployable multimode radiation sensor. The computational study utilized MCNP6 code to investigate the response of CLYC to various incident radiations and to determine the feasibility of its application as a handheld multimode sensor and as a single-scintillator collimated directional detection system. These simulations include: • Characterization of the response of the CLYC scintillator to gamma-rays and neutrons; • Study of the isotopic enrichment of 7Li versus 6Li in the CLYC for optimal detection of both thermal neutrons and fast neutrons; • Analysis of collimator designs to determine the optimal collimator for the single CLYC sensor directional detection system to assay gamma rays and neutrons; Simulations of a handheld CLYC multimode sensor and a single CLYC scintillator collimated directional detection system with the optimized collimator to determine the feasibility of detecting nuclear materials that could be encountered during field operations. These nuclear materials include depleted uranium, natural uranium, low-enriched uranium, highly-enriched uranium, reactor-grade plutonium, and weapons-grade plutonium. The experimental study includes the design, construction, and testing of both a handheld CLYC multimode sensor and a single CLYC scintillator collimated directional detection system. Both were designed in the Inventor CAD software and based on results of the computational study to optimize its performance. The handheld CLYC multimode sensor is modular, scalable, low?power, and optimized for high count rates. Commercial?off?the?shelf components were used where possible in order to optimize size, increase robustness, and minimize cost. The handheld CLYC multimode

  7. Evaluation of conventional and high-performance routine solar radiation measurements for improved solar resource, climatological trends, and radiative modeling

    Energy Technology Data Exchange (ETDEWEB)

    Gueymard, Christian A. [Solar Consulting Services, P.O. Box 392, Colebrook, NH 03576 (United States); Myers, Daryl R. [National Renewable Energy Laboratory, 1617 Cole Blvd., Golden, CO 80401-3305 (United States)

    2009-02-15

    The solar renewable energy community depends on radiometric measurements and instrumentation for data to design and monitor solar energy systems, and develop and validate solar radiation models. This contribution evaluates the impact of instrument uncertainties contributing to data inaccuracies and their effect on short-term and long-term measurement series, and on radiation model validation studies. For the latter part, transposition (horizontal-to-tilt) models are used as an example. Confirming previous studies, it is found that a widely used pyranometer strongly underestimates diffuse and global radiation, particularly in winter, unless appropriate corrective measures are taken. Other types of measurement problems are also discussed, such as those involved in the indirect determination of direct or diffuse irradiance, and in shadowband correction methods. The sensitivity of the predictions from transposition models to inaccuracies in input radiation data is demonstrated. Caution is therefore issued to the whole community regarding drawing detailed conclusions about solar radiation data without due attention to the data quality issues only recently identified. (author)

  8. Estimating shortwave solar radiation using net radiation and meteorological measurements

    Science.gov (United States)

    Shortwave radiation has a wide variety of uses in land-atmosphere interactions research. Actual evapotranspiration estimation that involves stomatal conductance models like Jarvis and Ball-Berry require shortwave radiation to estimate photon flux density. However, in most weather stations, shortwave...

  9. The role of solar ultraviolet radiation in 'natural' water purification

    International Nuclear Information System (INIS)

    Calkins, J.; Buckles, J.D.; Moeller, J.R.

    1976-01-01

    The concentration of Eschericia coli in the input and output of a tertiary wastewater system (4 lagoons) has been monitored over an 11 month period. The integrated flux of biologically active solar ultraviolet (UV) radiation was measured during this period. By also determining (1) the effective temperature in the system, (2) the growth rate of E.coli at the effective temperature, (3) the penetration of the solar UV into the lagoons, (4) the dose-response relation for killing of E.coli by UV and (5) the retention time of water in the system, it is possible to compare the 'die off' expected from solar UV exposure to the actual 'die off' observed for different batches of water. The observed killing of E.coli was quite close to the values calculated, considering the numerous factors involved. Solar UV light would thus seem to be a very important factor in the natural purification of water. Because each successful species must possess characteristics (physiological or behavioral) which provide adequate resistance to solar UV, the ecological role of solar UV radiation has not been widely appreciated. (author)

  10. Role of solar ultraviolet radiation in 'natural' water purification

    Energy Technology Data Exchange (ETDEWEB)

    Calkins, J; Buckles, J D; Moeller, J R [Kentucky Univ., Lexington (USA)

    1976-07-01

    The concentration of Eschericia coli in the input and output of a tertiary wastewater system (4 lagoons) has been monitored over an 11 month period. The integrated flux of biologically active solar ultraviolet (UV) radiation was measured during this period. By also determining (1) the effective temperature in the system, (2) the growth rate of E.coli at the effective temperature, (3) the penetration of the solar UV into the lagoons, (4) the dose-response relation for killing of E.coli by UV and (5) the retention time of water in the system, it is possible to compare the 'die off' expected from solar UV exposure to the actual 'die off' observed for different batches of water. The observed killing of E.coli was quite close to the values calculated, considering the numerous factors involved. Solar UV light would thus seem to be a very important factor in the natural purification of water. Because each successful species must possess characteristics (physiological or behavioral) which provide adequate resistance to solar UV, the ecological role of solar UV radiation has not been widely appreciated.

  11. new model for solar radiation estimation from measured air

    African Journals Online (AJOL)

    HOD

    RMSE) and correlation ... countries due to the unavailability of measured data in place [3-5]. ... models were used to predict solar radiation in Nigeria by. [12-15]. However ..... "Comparison of Gene Expression Programming with neuro-fuzzy and ...

  12. Improved Solar-Radiation-Pressure Models for GPS Satellites

    Science.gov (United States)

    Bar-Sever, Yoaz; Kuang, Da

    2006-01-01

    A report describes a series of computational models conceived as an improvement over prior models for determining effects of solar-radiation pressure on orbits of Global Positioning System (GPS) satellites. These models are based on fitting coefficients of Fourier functions of Sun-spacecraft- Earth angles to observed spacecraft orbital motions.

  13. Glacial Influences on Solar Radiation in a Subarctic Sea.

    Science.gov (United States)

    Understanding macroscale processes controlling solar radia­tion in marine systems will be important in interpreting the potential effects of global change from increasing ultraviolet radiation (UV) and glacial retreat. This study provides the first quantitative assessment of UV i...

  14. Effect of solar radiation on surface ozone in Cairo

    Energy Technology Data Exchange (ETDEWEB)

    Rizk, H F.S. [National Research Centre, Air Pollution Research Dept., Cairo (Egypt)

    1992-04-01

    Measurements of surface ozone content over an urban area in Cairo were conducted during a year, May 1989 to April 1990, while solar radiation at the same area was measured. Low and high concentrations of ozone are compared with those recommended by the WHO expert committee regarding the daily cycle of ozone concentration. 15 refs.

  15. Empirical Models for the Estimation of Global Solar Radiation in ...

    African Journals Online (AJOL)

    Empirical Models for the Estimation of Global Solar Radiation in Yola, Nigeria. ... and average daily wind speed (WS) for the interval of three years (2010 – 2012) measured using various instruments for Yola of recorded data collected from the Center for Atmospheric Research (CAR), Anyigba are presented and analyzed.

  16. A comparison of outer electron radiation belt dropouts during solar ...

    Indian Academy of Sciences (India)

    Utilizing multiple data sources from the year 1997–2007, this study identifies radiation belt electron dropouts which are ultimately triggered when solar wind stream interfaces (SI) arrived at ... Center for Space Research, School for Physical and Chemical Sciences, North–West University, Potchefstroom 2520, South Africa.

  17. Ultraviolet solar radiation and the prevention of erythema

    International Nuclear Information System (INIS)

    Tena, F.; Martinez-Lozano, J.A.; Utrillas, M.P.

    1998-01-01

    An ultraviolet index appropriate for its use in Spain is studied on the basis of those already available in other countries. The suitability of this index to characterise ultraviolet solar radiation and, particularly, the potential risks to human health are discussed. Finally, the main factors affecting this index are identified and their influence is studied. (Author) 43 refs

  18. Estimation of solar radiation energy of Ethiopia from sunshine data

    Energy Technology Data Exchange (ETDEWEB)

    Argaw, N. [Tampere Univ., Dep. of Civil Engineering, Tampere (Finland)

    1996-12-31

    Measurements of global solar radiation on a horizontal surface, for nine meteorological stations in Ethiopia, are compared with their corresponding values computed based on Angstroem relations. Regression coefficients are obtained and correlation equations are determined to predict the global solar radiation. The results shows that Angstroem relations are valid for Ethiopian locations, and the correlation equations can be used to predict the monthly mean daily global solar radiation in the locations considered in this study. This study also proves that the results made by ENEC et al, using the generalised Frere`s coefficients, is unsatisfactory for the prediction of monthly mean daily global solar radiation. On the other hand, the work of Dogniaux and Lemoine, using the regression coefficients a and b as a function of latitude and atmospheric turbidity and grouping large range latitudes to extend the application, can give better estimation. However, for more accurate estimation, several additional meteorological stations have to be evaluated and their regression coefficients have to be determined before grouping in to one relationship to express the variations of a and b under any conditions of equipment and location. (author) 1 fig., 11 tabs., 22 refs.

  19. Ambient solar UV radiation and seasonal trends in potential sunburn ...

    African Journals Online (AJOL)

    Background. The detrimental effects of excess personal solar ultraviolet (UV) radiation exposure include sunburn, immunosuppression and skin cancer. In South Africa, individuals with minimum natural protection from melanin, including fair-skinned individuals and African albinos, and people spending extended ...

  20. Comparison Of Diffuse Solar Radiation Models Using Data For ...

    African Journals Online (AJOL)

    Measurements of global solar radiation and sunshine duration data during the period from 1984 to 1999 were supplied by IITA (International Institute of Tropical Agriculture) at Onne. The data were used to establish empirical relationships that would connect the daily monthly average diffuse irradiation with both relative ...

  1. Galactic and solar radiation exposure to aircrew during a solar cycle

    International Nuclear Information System (INIS)

    Lewis, B.J.; Bennett, L.G.I.; Green, A.R.; McCall, M.J.; Ellaschuk, B.; Butler, A.; Pierre, M.

    2002-01-01

    An on-going investigation using a tissue-equivalent proportional counter (TEPC) has been carried out to measure the ambient dose equivalent rate of the cosmic radiation exposure of aircrew during a solar cycle. A semi-empirical model has been derived from these data to allow for the interpolation of the dose rate for any global position. The model has been extended to an altitude of up to 32 km with further measurements made on board aircraft and several balloon flights. The effects of changing solar modulation during the solar cycle are characterised by correlating the dose rate data to different solar potential models. Through integration of the dose-rate function over a great circle flight path or between given waypoints, a Predictive Code for Aircrew Radiation Exposure has been further developed for estimation of the route dose from galactic cosmic radiation exposure. This estimate is provided in units of ambient dose equivalent as well as effective dose, based on E/H*(10) scaling functions as determined from transport code calculations with LUIN and FLUKA. This experimentally based treatment has also been compared with the CARI-6 and EPCARD codes that are derived solely from theoretical transport calculations. Using TEPC measurements taken aboard the International Space Station, ground based neutron monitoring, GOES satellite data and transport code analysis, an empirical model has been further proposed for estimation of aircrew exposure during solar particle events. This model has been compared to results obtained during recent solar flare events. (author)

  2. Assessment and comparison of methods for solar ultraviolet radiation measurements

    Energy Technology Data Exchange (ETDEWEB)

    Leszczynski, K

    1995-06-01

    In the study, the different methods to measure the solar ultraviolet radiation are compared. The methods included are spectroradiometric, erythemally weighted broadband and multi-channel measurements. The comparison of the different methods is based on a literature review and assessments of optical characteristics of the spectroradiometer Optronic 742 of the Finnish Centre for Radiation and Nuclear Safety (STUK) and of the erythemally weighted Robertson-Berger type broadband radiometers Solar Light models 500 and 501 of the Finnish Meteorological Institute and STUK. An introduction to the sources of error in solar UV measurements, to methods for radiometric characterization of UV radiometers together with methods for error reduction are presented. Reviews on experiences from world-wide UV monitoring efforts and instrumentation as well as on the results from international UV radiometer intercomparisons are also presented. (62 refs.).

  3. Assessment and comparison of methods for solar ultraviolet radiation measurements

    International Nuclear Information System (INIS)

    Leszczynski, K.

    1995-06-01

    In the study, the different methods to measure the solar ultraviolet radiation are compared. The methods included are spectroradiometric, erythemally weighted broadband and multi-channel measurements. The comparison of the different methods is based on a literature review and assessments of optical characteristics of the spectroradiometer Optronic 742 of the Finnish Centre for Radiation and Nuclear Safety (STUK) and of the erythemally weighted Robertson-Berger type broadband radiometers Solar Light models 500 and 501 of the Finnish Meteorological Institute and STUK. An introduction to the sources of error in solar UV measurements, to methods for radiometric characterization of UV radiometers together with methods for error reduction are presented. Reviews on experiences from world-wide UV monitoring efforts and instrumentation as well as on the results from international UV radiometer intercomparisons are also presented. (62 refs.)

  4. Estimation of clear sky hourly global solar radiation in Iraq

    Energy Technology Data Exchange (ETDEWEB)

    Al-Jumaily, Kais J.; Al-Zuhairi, Munya F.; Mahdi, Zahraa S. [Department of Atmospheric Sciences, College of Science, Al-Mustansiriyah University, Baghdad (Iraq)

    2012-07-01

    The availability of hourly solar radiation data is very important for applications utilizing solar energy and for climate and environmental aspects. The aim of this work is to use a simple model for estimating hourly global solar radiation under clear sky condition in Iraq. Calculations were compared with measurements obtained from local station in Baghdad city and from Meteosat satellite data for different locations in Iraq. The statistical test methods of the mean bias error (MBE), root mean square error (RMSE) and t-test were used to evaluate the performance of the model. Results indicated that a fairly good agreement exists between calculated and measured values for all locations in Iraq. Since the model is independent of any meteorological variable, it would be of a practical use for rural areas where no meteorological data are available.

  5. Comparison of Gene Expression Programming with neuro-fuzzy and neural network computing techniques in estimating daily incoming solar radiation in the Basque Country (Northern Spain)

    International Nuclear Information System (INIS)

    Landeras, Gorka; López, José Javier; Kisi, Ozgur; Shiri, Jalal

    2012-01-01

    Highlights: ► Solar radiation estimation based on Gene Expression Programming is unexplored. ► This approach is evaluated for the first time in this study. ► Other artificial intelligence models (ANN and ANFIS) are also included in the study. ► New alternatives for solar radiation estimation based on temperatures are provided. - Abstract: Surface incoming solar radiation is a key variable for many agricultural, meteorological and solar energy conversion related applications. In absence of the required meteorological sensors for the detection of global solar radiation it is necessary to estimate this variable. Temperature based modeling procedures are reported in this study for estimating daily incoming solar radiation by using Gene Expression Programming (GEP) for the first time, and other artificial intelligence models such as Artificial Neural Networks (ANNs), and Adaptive Neuro-Fuzzy Inference System (ANFIS). A comparison was also made among these techniques and traditional temperature based global solar radiation estimation equations. Root mean square error (RMSE), mean absolute error (MAE) RMSE-based skill score (SS RMSE ), MAE-based skill score (SS MAE ) and r 2 criterion of Nash and Sutcliffe criteria were used to assess the models’ performances. An ANN (a four-input multilayer perceptron with 10 neurons in the hidden layer) presented the best performance among the studied models (2.93 MJ m −2 d −1 of RMSE). The ability of GEP approach to model global solar radiation based on daily atmospheric variables was found to be satisfactory.

  6. The solar energy in Colombia, Atlas of solar radiation of Colombia

    International Nuclear Information System (INIS)

    Rodriguez P, F.

    1995-01-01

    This study was made by means of the Agreement inter-institutional subscribed between Mines Ministry and Energy, HIMAT and INEA and was published by CARBOCOL. In the evaluation of solar energy potential, the information of the radiometric net of the HIMAT taken in 203 stations distributed throughout all Country from 1980 until 1990, it was had in account. A meteorological station is an observation point where are located different instruments and equipment that serve to measure and study meteorological parameter as solar radiation (radiometer actinograph), Solar sheen (Campbell Stoke), Temperature (Thermograph), Moisture (hydrographer), Wind (Anemograph Anemometer) and Precipitation (Pluviograph)

  7. Open-WiSe: a solar powered wireless sensor network platform.

    Science.gov (United States)

    González, Apolinar; Aquino, Raúl; Mata, Walter; Ochoa, Alberto; Saldaña, Pedro; Edwards, Arthur

    2012-01-01

    Because battery-powered nodes are required in wireless sensor networks and energy consumption represents an important design consideration, alternate energy sources are needed to provide more effective and optimal function. The main goal of this work is to present an energy harvesting wireless sensor network platform, the Open Wireless Sensor node (WiSe). The design and implementation of the solar powered wireless platform is described including the hardware architecture, firmware, and a POSIX Real-Time Kernel. A sleep and wake up strategy was implemented to prolong the lifetime of the wireless sensor network. This platform was developed as a tool for researchers investigating Wireless sensor network or system integrators.

  8. Adaptive sensor-based ultra-high accuracy solar concentrator tracker

    Science.gov (United States)

    Brinkley, Jordyn; Hassanzadeh, Ali

    2017-09-01

    Conventional solar trackers use information of the sun's position, either by direct sensing or by GPS. Our method uses the shading of the receiver. This, coupled with nonimaging optics design allows us to achieve ultra-high concentration. Incorporating a sensor based shadow tracking method with a two stage concentration solar hybrid parabolic trough allows the system to maintain high concentration with acute accuracy.

  9. Investigation of Solar Hybrid Electric/Thermal System with Radiation Concentrator and Thermoelectric Generator

    Directory of Open Access Journals (Sweden)

    Edgar Arturo Chávez Urbiola

    2013-01-01

    Full Text Available An experimental study of a solar-concentrating system based on thermoelectric generators (TEGs was performed. The system included an electrical generating unit with 6 serially connected TEGs using a traditional semiconductor material, Bi2Te3, which was illuminated by concentrated solar radiation on one side and cooled by running water on the other side. A sun-tracking concentrator with a mosaic set of mirrors was used; its orientation towards the sun was achieved with two pairs of radiation sensors, a differential amplifier, and two servomotors. The hot side of the TEGs at midday has a temperature of around 200°C, and the cold side is approximately 50°C. The thermosiphon cooling system was designed to absorb the heat passing through the TEGs and provide optimal working conditions. The system generates 20 W of electrical energy and 200 W of thermal energy stored in water with a temperature of around 50°C. The hybrid system studied can be considered as an alternative to photovoltaic/thermal systems, especially in countries with abundant solar radiation, such as Mexico, China, and India.

  10. Low power consumption and high temperature durability for radiation sensor

    International Nuclear Information System (INIS)

    Matsumoto, Yoshinori; Ueno, Hiroto

    2015-01-01

    Low power consumption and high temperature operation are important in an environmental monitoring system. The power consumption of 3 mW is achieved for the radiation sensor using low voltage operational amplifier and comparator in the signal processing circuit. The leakage reverse current of photodiode causes the charge amplifier saturation over 50degC. High temperature durability was improved by optimizing the circuit configuration and the values of feedback resistance and capacitance in the charge amplifier. The pulse response of the radiation sensor was measured up to 55degC. The custom detection circuit was designed by 0.6 μm CMOS process at 5-V supply voltage. The operation temperature was improved up to 65degC. (author)

  11. Placement and efficiency effects on radiative forcing of solar installations

    International Nuclear Information System (INIS)

    Burg, Brian R.; Ruch, Patrick; Paredes, Stephan; Michel, Bruno

    2015-01-01

    The promise for harnessing solar energy being hampered by cost, triggered efforts to reduce them. As a consequence low-efficiency, low-cost photovoltaics (PV) panels prevail. Conversely, in the traditional energy sector efficiency is extremely important due to the direct costs associated to fuels. This also affects solar energy due to the radiative forcing caused by the dark solar panels. In this paper we extend the concept of energy payback time by including the effect of albedo change, which gives a better assessment of the system sustainability. We present an analysis on the short and medium term climate forcing effects of different solar collectors in Riyadh, Saudi Arabia and demonstrate that efficiency is important to reduce the collector area and cost. This also influences the embodied energy and the global warming potential. We show that a placement of a high concentration photovoltaic thermal solar power station outside of the city using a district cooling system has a double beneficial effect since it improves the solar conversion efficiency and reduces the energy demand for cooling in the city. We also explain the mechanisms of the current economic development of solar technologies and anticipate changes

  12. Placement and efficiency effects on radiative forcing of solar installations

    Energy Technology Data Exchange (ETDEWEB)

    Burg, Brian R.; Ruch, Patrick; Paredes, Stephan; Michel, Bruno, E-mail: bmi@zurich.ibm.com [IBM Research - Zurich, Säumerstrasse 4, CH-8803 Rüschlikon (Switzerland)

    2015-09-28

    The promise for harnessing solar energy being hampered by cost, triggered efforts to reduce them. As a consequence low-efficiency, low-cost photovoltaics (PV) panels prevail. Conversely, in the traditional energy sector efficiency is extremely important due to the direct costs associated to fuels. This also affects solar energy due to the radiative forcing caused by the dark solar panels. In this paper we extend the concept of energy payback time by including the effect of albedo change, which gives a better assessment of the system sustainability. We present an analysis on the short and medium term climate forcing effects of different solar collectors in Riyadh, Saudi Arabia and demonstrate that efficiency is important to reduce the collector area and cost. This also influences the embodied energy and the global warming potential. We show that a placement of a high concentration photovoltaic thermal solar power station outside of the city using a district cooling system has a double beneficial effect since it improves the solar conversion efficiency and reduces the energy demand for cooling in the city. We also explain the mechanisms of the current economic development of solar technologies and anticipate changes.

  13. Development of software for estimating clear sky solar radiation in Indonesia

    Science.gov (United States)

    Ambarita, H.

    2017-01-01

    Research on solar energy applications in Indonesia has come under scrutiny in recent years. Solar radiation is harvested by solar collector or solar cell and convert the energy into useful energy such as heat and or electricity. In order to provide a better configuration of a solar collector or a solar cell, clear sky radiation should be estimated properly. In this study, an in-house software for estimating clear sky radiation is developed. The governing equations are solved simultaneously. The software is tested in Medan city by performing a solar radiation measurements. For clear sky radiation, the results of the software and measurements ones show a good agreement. However, for the cloudy sky condition it cannot predict the solar radiation. This software can be used to estimate the clear sky radiation in Indonesia.

  14. Effects of solar radiation on hair and photoprotection.

    Science.gov (United States)

    Dario, Michelli F; Baby, André R; Velasco, Maria Valéria R

    2015-12-01

    In this paper the negative effects of solar radiation (ultraviolet, visible and infrared wavelengths) on hair properties like color, mechanical properties, luster, protein content, surface roughness, among others, will be discussed. Despite knowing that radiation damages hair, there are no consensus about the particular effect of each segment of solar radiation on the hair shaft. The hair photoprotection products are primarily targeted to dyed hair, specially auburn pigments, and gray shades. They are usually based on silicones, antioxidants and quaternary chemical UV filters that have more affinity for negatively charged hair surface and present higher efficacy. Unfortunately, there are no regulated parameters, like for skin photoprotection, for efficacy evaluation of hair care products, which makes impossible to compare the results published in the literature. Thus, it is important that researchers make an effort to apply experimental conditions similar to a real level of sun exposure, like dose, irradiance, time, temperature and relative humidity. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Radiation Environments for Future Human Exploration Throughout the Solar System.

    Science.gov (United States)

    Schwadron, N.; Gorby, M.; Linker, J.; Riley, P.; Torok, T.; Downs, C.; Spence, H. E.; Desai, M. I.; Mikic, Z.; Joyce, C. J.; Kozarev, K. A.; Townsend, L. W.; Wimmer-Schweingruber, R. F.

    2016-12-01

    Acute space radiation hazards pose one of the most serious risks to future human and robotic exploration. The ability to predict when and where large events will occur is necessary in order to mitigate their hazards. The largest events are usually associated with complex sunspot groups (also known as active regions) that harbor strong, stressed magnetic fields. Highly energetic protons accelerated very low in the corona by the passage of coronal mass ejection (CME)-driven compressions or shocks and from flares travel near the speed of light, arriving at Earth minutes after the eruptive event. Whether these particles actually reach Earth, the Moon, Mars (or any other point) depends on their transport in the interplanetary magnetic field and their magnetic connection to the shock. Recent contemporaneous observations during the largest events in almost a decade show the unique longitudinal distributions of this ionizing radiation broadly distributed from sources near the Sun and yet highly isolated during the passage of CME shocks. Over the last decade, we have observed space weather events as the solar wind exhibits extremely low densities and magnetic field strengths, representing states that have never been observed during the space age. The highly abnormal solar activity during cycles 23 and 24 has caused the longest solar minimum in over 80 years and continues into the unusually small solar maximum of cycle 24. As a result of the remarkably weak solar activity, we have also observed the highest fluxes of galactic cosmic rays in the space age and relatively small particle radiation events. We have used observations from LRO/CRaTER to examine the implications of these highly unusual solar conditions for human space exploration throughout the inner solar system. While these conditions are not a show-stopper for long-duration missions (e.g., to the Moon, an asteroid, or Mars), galactic cosmic ray radiation remains a significant and worsening factor that limits

  16. Temperature based daily incoming solar radiation modeling based on gene expression programming, neuro-fuzzy and neural network computing techniques.

    Science.gov (United States)

    Landeras, G.; López, J. J.; Kisi, O.; Shiri, J.

    2012-04-01

    The correct observation/estimation of surface incoming solar radiation (RS) is very important for many agricultural, meteorological and hydrological related applications. While most weather stations are provided with sensors for air temperature detection, the presence of sensors necessary for the detection of solar radiation is not so habitual and the data quality provided by them is sometimes poor. In these cases it is necessary to estimate this variable. Temperature based modeling procedures are reported in this study for estimating daily incoming solar radiation by using Gene Expression Programming (GEP) for the first time, and other artificial intelligence models such as Artificial Neural Networks (ANNs), and Adaptive Neuro-Fuzzy Inference System (ANFIS). Traditional temperature based solar radiation equations were also included in this study and compared with artificial intelligence based approaches. Root mean square error (RMSE), mean absolute error (MAE) RMSE-based skill score (SSRMSE), MAE-based skill score (SSMAE) and r2 criterion of Nash and Sutcliffe criteria were used to assess the models' performances. An ANN (a four-input multilayer perceptron with ten neurons in the hidden layer) presented the best performance among the studied models (2.93 MJ m-2 d-1 of RMSE). A four-input ANFIS model revealed as an interesting alternative to ANNs (3.14 MJ m-2 d-1 of RMSE). Very limited number of studies has been done on estimation of solar radiation based on ANFIS, and the present one demonstrated the ability of ANFIS to model solar radiation based on temperatures and extraterrestrial radiation. By the way this study demonstrated, for the first time, the ability of GEP models to model solar radiation based on daily atmospheric variables. Despite the accuracy of GEP models was slightly lower than the ANFIS and ANN models the genetic programming models (i.e., GEP) are superior to other artificial intelligence models in giving a simple explicit equation for the

  17. Digging the METEOSAT Treasure—3 Decades of Solar Surface Radiation

    Directory of Open Access Journals (Sweden)

    Richard Müller

    2015-06-01

    Full Text Available Solar surface radiation data of high quality is essential for the appropriate monitoring and analysis of the Earth's radiation budget and the climate system. Further, they are crucial for the efficient planning and operation of solar energy systems. However, well maintained surface measurements are rare in many regions of the world and over the oceans. There, satellite derived information is the exclusive observational source. This emphasizes the important role of satellite based surface radiation data. Within this scope, the new satellite based CM-SAF SARAH (Solar surfAce RAdiation Heliosat data record is discussed as well as the retrieval method used. The SARAH data are retrieved with the sophisticated SPECMAGIC method, which is based on radiative transfer modeling. The resulting climate data of solar surface irradiance, direct irradiance (horizontal and direct normal and clear sky irradiance are covering 3 decades. The SARAH data set is validated with surface measurements of the Baseline Surface Radiation Network (BSRN and of the Global Energy and Balance Archive (GEBA. Comparison with BSRN data is performed in order to estimate the accuracy and precision of the monthly and daily means of solar surface irradiance. The SARAH solar surface irradiance shows a bias of 1.3 \\(W/m^2\\ and a mean absolute bias (MAB of 5.5 \\(W/m^2\\ for monthly means. For direct irradiance the bias and MAB is 1 \\(W/m^2\\ and 8.2 \\(W/m^2\\ respectively. Thus, the uncertainty of the SARAH data is in the range of the uncertainty of ground based measurements. In order to evaluate the uncertainty of SARAH based trend analysis the time series of SARAH monthly means are compared to GEBA. It has been found that SARAH enables the analysis of trends with an uncertainty of 1 \\(W/m^2/dec\\; a remarkable good result for a satellite based climate data record. SARAH has been also compared to its legacy version, the satellite based CM-SAF MVIRI climate data record. Overall

  18. Electric field deformation in diamond sensors induced by radiation defects

    Energy Technology Data Exchange (ETDEWEB)

    Kassel, Florian; Boer, Wim de; Boegelspacher, Felix; Dierlamm, Alexander; Mueller, Thomas; Steck, Pia [Institut fuer Experimentelle Kernphysik (IEKP), Karlsruher Institut fuer Technologie (KIT) (Germany); Dabrowski, Anne; Guthoff, Moritz [CERN (Switzerland)

    2016-07-01

    The BCML system is a beam monitoring device in the CMS experiment at the LHC. As detectors 32 poly-crystalline CVD diamond sensors are positioned in a ring around the beam pipe at a distance of ±1.8 m and ±14.4 m from the interaction point. The radiation hardness of the diamond sensors in terms of measured signal during operation was significantly lower than expected from laboratory measurements. At high particle rates, such as those occurring during the operation of the LHC, a significant fraction of the defects act as traps for charge carriers. This space charge modifies the electrical field in the sensor bulk leading to a reduction of the charge collection efficiency (CCE). A diamond irradiation campaign was started to investigate the rate dependent electrical field deformation with respect to the radiation damage. Besides the electrical field measurements via the Transient Current Technique, the CCE was measured. The experimental results were used to create an effective trap model that takes the radiation damage into account. Using this trap model the rate dependent electrical field deformation and the CCE were simulated with the software ''SILVACO TCAD''. This talk compares the experimental measurement results with the simulations.

  19. Review of the development of diamond radiation sensors

    Energy Technology Data Exchange (ETDEWEB)

    Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J. E-mail: josel.hrubec@cern.ch; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Knoepfle, K.T.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P.F.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Mishina, M.; Oh, A.; Pan, L.S.; Palmieri, V.G.; Pernicka, M.; Peitz, A.; Pirollo, S.; Polesello, P.; Pretzl, K.; Re, V.; Riester, J.L.; Roe, S.; Roff, D.; Rudge, A.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Tapper, R.J.; Tesarek, R.; Thomson, G.B.; Trawick, M.; Trischuk, W.; Vittone, E.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Ziock, H.; Zoeller, M

    1999-09-11

    Diamond radiation sensors produced by chemical vapour deposition are studied for the application as tracking detectors in high luminosity experiments. Sensors with a charge collection distance up to 250 {mu}m have been manufactured. Their radiation hardness has been studied with pions, proton and neutrons up to fluences of 1.9x10{sup 15} {pi} cm{sup -2}, 5x10{sup 15} p cm{sup -2} and 1.35x10{sup 15} n cm{sup -2}, respectively. Diamond micro-strip detectors with 50 {mu}m pitch have been exposed in a high-energy test beam in order to investigate their charge collection properties. The measured spatial resolution using a centre-of-gravity position finding algorithm corresponds to the digital resolution for this strip pitch. First results from a strip tracker with a 2x4 cm{sup 2} surface area are reported as well as the performance of a diamond tracker read out by radiation-hard electronics with 25 ns shaping time. Diamond pixel sensors have been prepared to match the geometries of the recently available read-out chip prototypes for ATLAS and CMS. Beam test results are shown from a diamond detector bump-bonded to an ATLAS prototype read-out. They demonstrate a 98% bump-bonding efficiency and a digital resolution in both dimensions. (author)

  20. Review of the development of diamond radiation sensors

    International Nuclear Information System (INIS)

    Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; Eijk, B. van; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K.K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Knoepfle, K.T.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P.F.; Manfredotti, C.; Marshall, R.D.; Meier, D.; Mishina, M.; Oh, A.; Pan, L.S.; Palmieri, V.G.; Pernicka, M.; Peitz, A.; Pirollo, S.; Polesello, P.; Pretzl, K.; Re, V.; Riester, J.L.; Roe, S.; Roff, D.; Rudge, A.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Tapper, R.J.; Tesarek, R.; Thomson, G.B.; Trawick, M.; Trischuk, W.; Vittone, E.; Walsh, A.M.; Wedenig, R.; Weilhammer, P.; Ziock, H.; Zoeller, M.

    1999-01-01

    Diamond radiation sensors produced by chemical vapour deposition are studied for the application as tracking detectors in high luminosity experiments. Sensors with a charge collection distance up to 250 μm have been manufactured. Their radiation hardness has been studied with pions, proton and neutrons up to fluences of 1.9x10 15 π cm -2 , 5x10 15 p cm -2 and 1.35x10 15 n cm -2 , respectively. Diamond micro-strip detectors with 50 μm pitch have been exposed in a high-energy test beam in order to investigate their charge collection properties. The measured spatial resolution using a centre-of-gravity position finding algorithm corresponds to the digital resolution for this strip pitch. First results from a strip tracker with a 2x4 cm 2 surface area are reported as well as the performance of a diamond tracker read out by radiation-hard electronics with 25 ns shaping time. Diamond pixel sensors have been prepared to match the geometries of the recently available read-out chip prototypes for ATLAS and CMS. Beam test results are shown from a diamond detector bump-bonded to an ATLAS prototype read-out. They demonstrate a 98% bump-bonding efficiency and a digital resolution in both dimensions. (author)

  1. Review of the development of diamond radiation sensors

    Science.gov (United States)

    Adam, W.; Bauer, C.; Berdermann, E.; Bergonzo, P.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; Dabrowski, W.; Delpierre, P.; Deneuville, A.; Dulinski, W.; van Eijk, B.; Fallou, A.; Fizzotti, F.; Foulon, F.; Friedl, M.; Gan, K. K.; Gheeraert, E.; Grigoriev, E.; Hallewell, G.; Hall-Wilton, R.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kania, D.; Kaplon, J.; Karl, C.; Kass, R.; Knöpfle, K. T.; Krammer, M.; Logiudice, A.; Lu, R.; Manfredi, P. F.; Manfredotti, C.; Marshall, R. D.; Meier, D.; Mishina, M.; Oh, A.; Pan, L. S.; Palmieri, V. G.; Pernicka, M.; Peitz, A.; Pirollo, S.; Polesello, P.; Pretzl, K.; Re, V.; Riester, J. L.; Roe, S.; Roff, D.; Rudge, A.; Schnetzer, S.; Sciortino, S.; Speziali, V.; Stelzer, H.; Stone, R.; Tapper, R. J.; Tesarek, R.; Thomson, G. B.; Trawick, M.; Trischuk, W.; Vittone, E.; Walsh, A. M.; Wedenig, R.; Weilhammer, P.; Ziock, H.; Zoeller, M.; RD42 Collaboration

    1999-09-01

    Diamond radiation sensors produced by chemical vapour deposition are studied for the application as tracking detectors in high luminosity experiments. Sensors with a charge collection distance up to 250 μm have been manufactured. Their radiation hardness has been studied with pions, proton and neutrons up to fluences of 1.9×10 15 π cm -2, 5×10 15 p cm -2 and 1.35×10 15 n cm -2, respectively. Diamond micro-strip detectors with 50 μm pitch have been exposed in a high-energy test beam in order to investigate their charge collection properties. The measured spatial resolution using a centre-of-gravity position finding algorithm corresponds to the digital resolution for this strip pitch. First results from a strip tracker with a 2×4 cm 2 surface area are reported as well as the performance of a diamond tracker read out by radiation-hard electronics with 25 ns shaping time. Diamond pixel sensors have been prepared to match the geometries of the recently available read-out chip prototypes for ATLAS and CMS. Beam test results are shown from a diamond detector bump-bonded to an ATLAS prototype read-out. They demonstrate a 98% bump-bonding efficiency and a digital resolution in both dimensions.

  2. Review of the development of diamond radiation sensors

    CERN Document Server

    Adam, W; Berdermann, E; Bergonzo, P; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, Mara; Colledani, C; Conway, J; Dabrowski, W; Delpierre, P A; Deneuville, A; Dulinski, W; van Eijk, B; Fallou, A; Fizzotti, F; Foulon, F; Friedl, M; Gan, K K; Gheeraert, E; Grigoriev, E; Hallewell, G D; Hall-Wilton, R; Han, S; Hartjes, F G; Hrubec, Josef; Husson, D; Kagan, H; Kania, D R; Kaplon, J; Karl, C; Kass, R; Knöpfle, K T; Krammer, Manfred; Lo Giudice, A; Lü, R; Manfredi, P F; Manfredotti, C; Marshall, R D; Meier, D; Mishina, M; Oh, A; Pan, L S; Palmieri, V G; Pernicka, Manfred; Peitz, A; Pirollo, S; Polesello, P; Pretzl, Klaus P; Re, V; Riester, J L; Roe, S; Roff, D G; Rudge, A; Schnetzer, S R; Sciortino, S; Speziali, V; Stelzer, H; Stone, R; Tapper, R J; Tesarek, R J; Thomson, G B; Trawick, M L; Trischuk, W; Vittone, E; Walsh, A M; Wedenig, R; Weilhammer, Peter; Ziock, H J; Zöller, M

    1999-01-01

    Diamond radiation sensors produced by chemical vapour deposition are studied for the application as tracking detectors in high luminosity experiments. Sensors with a charge collection distance up to 250 mu m have been manufactured. Their radiation hardness has been studied with pions, proton and neutrons up to fluences of 1.9*10/sup 15/ pi cm/sup -2/, 5*10/sup 19/ p cm/sup -2/ and 1.35*10/sup 15/ n cm/sup -2 /, respectively. Diamond micro-strip detectors with 50 mu m pitch have been exposed in a high-energy test beam in order to investigate their charge collection properties. The measured spatial resolution using a centre-of-gravity position finding algorithm corresponds to the digital resolution for this strip pitch. First results from a strip tracker with a 2*4 cm/sup 2/ surface area are reported as well as the performance of a diamond tracker read out by radiation-hard electronics with 25 ns shaping time. Diamond pixel sensors have been prepared to match the geometries of the recently available read-out ch...

  3. Solar ultraviolet radiation in a changing climate

    Science.gov (United States)

    The projected large increases in damaging ultraviolet radiation as a result of global emissions of ozone-depleting substances have been forestalled by the success of the Montreal Protocol. New challenges are now arising in relation to climate change. We highlight the complex inte...

  4. Higher plant acclimation to solar ultraviolet-B radiation

    International Nuclear Information System (INIS)

    Robberecht, R.

    1981-01-01

    The objectives of this study were to determine: (1) the relationship between plant sensitivity and epidermal uv attenuation, (2) the effect of phenotypic changes in the leaf epidermis, resulting from uv-B exposure, on plant sensitivity to uv radiation, and (3) the platicity of these changes in the epidermis leading to plant acclimation to uv-B radiation. A mechanism of uv-B attenuation, possibly involving the biosynthesis of uv-absorbing flavonoid compounds in the epidermis and mesophyll under the stress of uv-B radiation, and a subsequent increase in the uv-B attenuation capacity of the epidermis, is suggested. The degree of plant sensitivity and acclimation to natural and intensified solar uv-B radiation may involve a dynamic balance between the capacity for uv-B attenuation and uv-radiation-repair mechanisms in the leaf

  5. Diffuse solar radiation estimation models for Turkey's big cities

    International Nuclear Information System (INIS)

    Ulgen, Koray; Hepbasli, Arif

    2009-01-01

    A reasonably accurate knowledge of the availability of the solar resource at any place is required by solar engineers, architects, agriculturists, and hydrologists in many applications of solar energy such as solar furnaces, concentrating collectors, and interior illumination of buildings. For this purpose, in the past, various empirical models (or correlations) have been developed in order to estimate the solar radiation around the world. This study deals with diffuse solar radiation estimation models along with statistical test methods used to statistically evaluate their performance. Models used to predict monthly average daily values of diffuse solar radiation are classified in four groups as follows: (i) From the diffuse fraction or cloudness index, function of the clearness index, (ii) From the diffuse fraction or cloudness index, function of the relative sunshine duration or sunshine fraction, (iii) From the diffuse coefficient, function of the clearness index, and (iv) From the diffuse coefficient, function of the relative sunshine duration or sunshine fraction. Empirical correlations are also developed to establish a relationship between the monthly average daily diffuse fraction or cloudness index (K d ) and monthly average daily diffuse coefficient (K dd ) with the monthly average daily clearness index (K T ) and monthly average daily sunshine fraction (S/S o ) for the three big cities by population in Turkey (Istanbul, Ankara and Izmir). Although the global solar radiation on a horizontal surface and sunshine duration has been measured by the Turkish State Meteorological Service (STMS) over all country since 1964, the diffuse solar radiation has not been measured. The eight new models for estimating the monthly average daily diffuse solar radiation on a horizontal surface in three big cites are validated, and thus, the most accurate model is selected for guiding future projects. The new models are then compared with the 32 models available in the

  6. Device Simulation of Monolithic Active Pixel Sensors: Radiation Damage Effects

    International Nuclear Information System (INIS)

    Fourches, N.T.

    2009-01-01

    Vertexing for the future International Linear Collider represents a challenging goal because of the high spatial resolution required with low material budget and high ionizing radiation tolerance. CMOS Monolithic Active Pixel Sensors (MAPS) represent a good potential solution for this purpose. Up to now many MAPS sensors have been developed. They are based on various architectures and manufactured in different processes. However, up so far, the sensor diode has not been the subject of extensive modelization and simulation. Published simulation studies of sensor-signal formation have been less numerous than measurements on real sensors. This is a cause for concern because such sensor is physically based on the partially depleted diode, in the vicinity of which the electric field collects the minority carriers generated by an incident MIP (minimum ionizing particle). Although the microscopic mechanisms are well known and modelled, the global physical mechanisms for signal formation are not very rigorously established. This is partly due to the presence of a predominant diffusion component in the charge transport. We present here simulations mainly based on the S-PISCES code, in which physical mechanisms affecting transport are taken into account. Diffusion, influence of residual carrier concentration due to the doping level in the sensitive volume, and more importantly charge trapping due to deep levels in the active (detecting) layer are studied together with geometric aspects. The effect of neutron irradiation is studied to assess the effects of deep traps. A comparison with available experimental data, obtained on processed MAPS before or after neutron irradiation will be introduced. Simulated reconstruction of the Minimum Ionizing Particle (MIP) point of impact in two dimensions is also investigated. For further steps, guidelines for process choices of next Monolithic Active Pixel Sensors are introduced. (authors)

  7. UV Irradiance Enhancements by Scattering of Solar Radiation from Clouds

    Directory of Open Access Journals (Sweden)

    Uwe Feister

    2015-08-01

    Full Text Available Scattering of solar radiation by clouds can reduce or enhance solar global irradiance compared to cloudless-sky irradiance at the Earth’s surface. Cloud effects to global irradiance can be described by Cloud Modification Factors (CMF. Depending on strength and duration, irradiance enhancements affect the energy balance of the surface and gain of solar power for electric energy generation. In the ultraviolet region, they increase the risk for damage to living organisms. Wavelength-dependent CMFs have been shown to reach 1.5 even in the UV-B region at low altitudes. Ground-based solar radiation measurements in the high Andes region at altitudes up to 5917 m a.s.l showed cloud-induced irradiance enhancements. While UV-A enhancements were explained by cloud scattering, both radiation scattering from clouds and Negative Ozone Anomalies (NOA have been discussed to have caused short-time enhancement of UV-B irradiance. Based on scenarios using published CMF and additional spectroradiometric measurements at a low-altitude site, the contribution of cloud scattering to the UV-B irradiance enhancement in the Andes region has been estimated. The range of UV index estimates converted from measured UV-B and UV-A irradiance and modeled cloudless-sky ratios UV-B/erythemal UV is compatible with an earlier estimate of an extreme UV index value of 43 derived for the high Andes.

  8. Modelling of aircrew radiation exposure during solar particle events

    Science.gov (United States)

    Al Anid, Hani Khaled

    In 1990, the International Commission on Radiological Protection recognized the occupational exposure of aircrew to cosmic radiation. In Canada, a Commercial and Business Aviation Advisory Circular was issued by Transport Canada suggesting that action should be taken to manage such exposure. In anticipation of possible regulations on exposure of Canadian-based aircrew in the near future, an extensive study was carried out at the Royal Military College of Canada to measure the radiation exposure during commercial flights. The radiation exposure to aircrew is a result of a complex mixed-radiation field resulting from Galactic Cosmic Rays (GCRs) and Solar Energetic Particles (SEPs). Supernova explosions and active galactic nuclei are responsible for GCRs which consist of 90% protons, 9% alpha particles, and 1% heavy nuclei. While they have a fairly constant fluence rate, their interaction with the magnetic field of the Earth varies throughout the solar cycles, which has a period of approximately 11 years. SEPs are highly sporadic events that are associated with solar flares and coronal mass ejections. This type of exposure may be of concern to certain aircrew members, such as pregnant flight crew, for which the annual effective dose is limited to 1 mSv over the remainder of the pregnancy. The composition of SEPs is very similar to GCRs, in that they consist of mostly protons, some alpha particles and a few heavy nuclei, but with a softer energy spectrum. An additional factor when analysing SEPs is the effect of flare anisotropy. This refers to the way charged particles are transported through the Earth's magnetosphere in an anisotropic fashion. Solar flares that are fairly isotropic produce a uniform radiation exposure for areas that have similar geomagnetic shielding, while highly anisotropic events produce variable exposures at different locations on the Earth. Studies of neutron monitor count rates from detectors sharing similar geomagnetic shielding properties

  9. Radiative equilibrium in solar prominences reconsidered

    Czech Academy of Sciences Publication Activity Database

    Heinzel, Petr; Anzer, U.

    2012-01-01

    Roč. 539, March (2012), A49/1-A49/6 ISSN 0004-6361 R&D Projects: GA ČR GA205/09/1705; GA ČR GAP209/10/1680 Institutional research plan: CEZ:AV0Z10030501 Keywords : Sun * radiative transfer Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 5.084, year: 2012

  10. Solar radiation on a catenary collector

    Science.gov (United States)

    Crutchik, M.; Appelbaum, J.

    1992-01-01

    A tent-shaped structure with a flexible photovoltaic blanket acting as a catenary collector is presented. The shadow cast by one side of the collector produces a shadow on the other side of the collector. This self-shading effect is analyzed. The direct beam, the diffuse, and the albedo radiation on the collector are determined. An example is given for the insolation on the collector operating on Viking Lander 1 (VL1).

  11. Ultra-Low Power Consuming Direct Radiation Sensors Based on Floating Gate Structures

    Directory of Open Access Journals (Sweden)

    Evgeny Pikhay

    2017-07-01

    Full Text Available In this paper, we report on ultra-low power consuming single poly floating gate direct radiation sensors. The developed devices are intended for total ionizing dose (TID measurements and fabricated in a standard CMOS process flow. Sensor design and operation is discussed in detail. Original array sensors were suggested and fabricated that allowed high statistical significance of the radiation measurements and radiation imaging functions. Single sensors and array sensors were analyzed in combination with the specially developed test structures. This allowed insight into the physics of sensor operations and exclusion of the phenomena related to material degradation under irradiation in the interpretation of the measurement results. Response of the developed sensors to various sources of ionizing radiation (Gamma, X-ray, UV, energetic ions was investigated. The optimal design of sensor for implementation in dosimetry systems was suggested. The roadmap for future improvement of sensor performance is suggested.

  12. Passive radiation detection using optically active CMOS sensors

    Science.gov (United States)

    Dosiek, Luke; Schalk, Patrick D.

    2013-05-01

    Recently, there have been a number of small-scale and hobbyist successes in employing commodity CMOS-based camera sensors for radiation detection. For example, several smartphone applications initially developed for use in areas near the Fukushima nuclear disaster are capable of detecting radiation using a cell phone camera, provided opaque tape is placed over the lens. In all current useful implementations, it is required that the sensor not be exposed to visible light. We seek to build a system that does not have this restriction. While building such a system would require sophisticated signal processing, it would nevertheless provide great benefits. In addition to fulfilling their primary function of image capture, cameras would also be able to detect unknown radiation sources even when the danger is considered to be low or non-existent. By experimentally profiling the image artifacts generated by gamma ray and β particle impacts, algorithms are developed to identify the unique features of radiation exposure, while discarding optical interaction and thermal noise effects. Preliminary results focus on achieving this goal in a laboratory setting, without regard to integration time or computational complexity. However, future work will seek to address these additional issues.

  13. Development and applications of monocrystalline silicon radiation sensors fabricated at Comision Nacional de Energia Atomica (CNEA)

    International Nuclear Information System (INIS)

    Bolzi, C; Bruno, C; Duran, J; Godfrin, E; Martinez Bogado, M; Pla, J; Tamasi, M

    2005-01-01

    The development of silicon photovoltaic sensors at CNEA has begun in 1998.These sensors, fabricated in the Photovoltaic Laboratory of the Solar Energy Group at Constituyentes Atomic Center, have been used to build low cost radiometers as well as solar angular position sensors on board of artificial satellites.The design, fabrication and calibration of these sensors have been made in different prototypes in order to analyze its performance and to evaluate its limitations.Nowadays, several commercial prototypes have been distributed in different laboratories of our country in order to evaluate them in real work conditions.Particularly, the first experiment of argentine solar cells on space performed on board of SAC-A satellite, included the fabrication of position sensors of this satellite as part of the alignment system of the solar array respect to the sun.In this article, the state of the art of monocrystalline silicon photovoltaic sensors fabricated at CNEA for terrestrial and space applications is presented

  14. Radiation Testing of PICA at the Solar Power Tower

    Science.gov (United States)

    White, Susan

    2010-01-01

    Sandia National Laboratory's Solar Power Tower was used to irradiate specimens of Phenolic Impregnated Carbon Ablator (PICA), in order to evaluate whether this thermal protection system material responded differently to potential shock layer radiative heating than to convective heating. Tests were run at 50, 100 and 150 Watts per square centimeter levels of concentrated solar radiation. Experimental results are presented both from spectral measurements on 1- 10 mm thick specimens of PICA, as well as from in-depth temperature measurements on instrumented thicker test specimens. Both spectral measurements and measured in-depth temperature profiles showed that, although it is a porous, low-density material, PICA does not exhibit problematic transparency to the tested high levels of NIR radiation, for all pragmatic cm-to-inch scale thicknesses. PICA acted as a surface absorber to efficiently absorb the incident visible and near infrared incident radiation in the top 2 millimeter layer in the Solar Power Tower tests up to 150 Watts per square centimeter.

  15. Leaf color is fine-tuned on the solar spectra to avoid strand direct solar radiation.

    Science.gov (United States)

    Kume, Atsushi; Akitsu, Tomoko; Nasahara, Kenlo Nishida

    2016-07-01

    The spectral distributions of light absorption rates by intact leaves are notably different from the incident solar radiation spectra, for reasons that remain elusive. Incident global radiation comprises two main components; direct radiation from the direction of the sun, and diffuse radiation, which is sunlight scattered by molecules, aerosols and clouds. Both irradiance and photon flux density spectra differ between direct and diffuse radiation in their magnitude and profile. However, most research has assumed that the spectra of photosynthetically active radiation (PAR) can be averaged, without considering the radiation classes. We used paired spectroradiometers to sample direct and diffuse solar radiation, and obtained relationships between the PAR spectra and the absorption spectra of photosynthetic pigments and organs. As monomers in solvent, the spectral absorbance of Chl a decreased with the increased spectral irradiance (W m(-2) nm(-1)) of global PAR at noon (R(2) = 0.76), and was suitable to avoid strong spectral irradiance (λmax = 480 nm) rather than absorb photon flux density (μmol m(-2) s(-1) nm(-1)) efficiently. The spectral absorption of photosystems and the intact thallus and leaves decreased linearly with the increased spectral irradiance of direct PAR at noon (I dir-max), where the wavelength was within the 450-650 nm range (R(2) = 0.81). The higher-order structure of photosystems systematically avoided the strong spectral irradiance of I dir-max. However, when whole leaves were considered, leaf anatomical structure and light scattering in leaf tissues made the leaves grey bodies for PAR and enabled high PAR use efficiency. Terrestrial green plants are fine-tuned to spectral dynamics of incident solar radiation and PAR absorption is increased in various structural hierarchies.

  16. Solar Weather Ice Monitoring Station (SWIMS). A low cost, extreme/harsh environment, solar powered, autonomous sensor data gathering and transmission system

    Science.gov (United States)

    Chetty, S.; Field, L. A.

    2013-12-01

    The Arctic ocean's continuing decrease of summer-time ice is related to rapidly diminishing multi-year ice due to the effects of climate change. Ice911 Research aims to develop environmentally respectful materials that when deployed will increase the albedo, enhancing the formation and/preservation of multi-year ice. Small scale deployments using various materials have been done in Canada, California's Sierra Nevada Mountains and a pond in Minnesota to test the albedo performance and environmental characteristics of these materials. SWIMS is a sophisticated autonomous sensor system being developed to measure the albedo, weather, water temperature and other environmental parameters. The system (SWIMS) employs low cost, high accuracy/precision sensors, high resolution cameras, and an extreme environment command and data handling computer system using satellite and terrestrial wireless communication. The entire system is solar powered with redundant battery backup on a floating buoy platform engineered for low temperature (-40C) and high wind conditions. The system also incorporates tilt sensors, sonar based ice thickness sensors and a weather station. To keep the costs low, each SWIMS unit measures incoming and reflected radiation from the four quadrants around the buoy. This allows data from four sets of sensors, cameras, weather station, water temperature probe to be collected and transmitted by a single on-board solar powered computer. This presentation covers the technical, logistical and cost challenges in designing, developing and deploying these stations in remote, extreme environments. Image captured by camera #3 of setting sun on the SWIMS station One of the images captured by SWIMS Camera #4

  17. Development of semiconductor radiation sensors for portable alarm-dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y. K.; Moon, B. S.; Chung, C. E.; Hong, S. B.; Kim, J. Y.; Kim, J. B.; Han, S. H.; Lee, W. G. [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2001-01-01

    We studied Semiconductor Radiation Sensors for Portable Alarm-Dosimeter. We calculated response functions for gamma energy 0.021, 0.122, 0.662, 0.835, 1.2 MeV using EGS4 codes. When we measured at various distance from source to detector, the detection efficiency of Si semiconductor detector was better than that of GM tube. The linear absorption coefficients of steel and aluminum plate were measured. These experimental results of the response of detector for intensity of radiation field coincide to the theoretical expectation. The count value of Si detector was changed with changing thickness of steel as changing threshold voltage of discriminator, and the linear absorption coefficient increased with increasing threshold voltage. Radiation detection efficiency shows difference at each threshold voltage condition. This results coincided to the theoretical simulation. 33 refs., 27 figs., 8 tabs. (Author)

  18. Radiation-stimulated processes in transistor temperature sensors

    International Nuclear Information System (INIS)

    Pavlyk, B. V.; Grypa, A. S.

    2016-01-01

    The features of the radiation-stimulated changes in the I–V and C–V characteristics of the emitter–base junction in KT3117 transistors are considered. It is shown that an increase in the current through the emitter junction is observed at the initial stage of irradiation (at doses of D < 4000 Gy for the “passive” irradiation mode and D < 5200 Gy for the “active” mode), which is caused by the effect of radiation-stimulated ordering of the defect-containing structure of the p–n junction. It is also shown that the X-ray irradiation (D < 14000 Gy), the subsequent relaxation (96 h), and thermal annealing (2 h at 400 K) of the transistor temperature sensors under investigation result in an increase in their radiation resistance.

  19. First tests of a novel radiation hard CMOS sensor process for Depleted Monolithic Active Pixel Sensors

    International Nuclear Information System (INIS)

    Pernegger, H.; Hoorne, J.W. van; Kugathasan, T.; Musa, L.; Riedler, P.; Riegel, C.; Schaefer, D.; Schioppa, E.J.; Snoeys, W.; Bates, R.; Buttar, C.; Maneuski, D.; Dalla, M.; Sbarra, C.

    2017-01-01

    The upgrade of the ATLAS [1] tracking detector for the High-Luminosity Large Hadron Collider (LHC) at CERN requires novel radiation hard silicon sensor technologies. Significant effort has been put into the development of monolithic CMOS sensors but it has been a challenge to combine a low capacitance of the sensing node with full depletion of the sensitive layer. Low capacitance brings low analog power. Depletion of the sensitive layer causes the signal charge to be collected by drift sufficiently fast to separate hits from consecutive bunch crossings (25 ns at the LHC) and to avoid losing the charge by trapping. This paper focuses on the characterization of charge collection properties and detection efficiency of prototype sensors originally designed in the framework of the ALICE Inner Tracking System (ITS) upgrade [2]. The prototypes are fabricated both in the standard TowerJazz 180nm CMOS imager process [3] and in an innovative modification of this process developed in collaboration with the foundry, aimed to fully deplete the sensitive epitaxial layer and enhance the tolerance to non-ionizing energy loss. Sensors fabricated in standard and modified process variants were characterized using radioactive sources, focused X-ray beam and test beams before and after irradiation. Contrary to sensors manufactured in the standard process, sensors from the modified process remain fully functional even after a dose of 10"1"5 n _e_q/cm"2, which is the the expected NIEL radiation fluence for the outer pixel layers in the future ATLAS Inner Tracker (ITk) [4].

  20. Neural network based method for conversion of solar radiation data

    International Nuclear Information System (INIS)

    Celik, Ali N.; Muneer, Tariq

    2013-01-01

    Highlights: ► Generalized regression neural network is used to predict the solar radiation on tilted surfaces. ► The above network, amongst many such as multilayer perceptron, is the most successful one. ► The present neural network returns a relative mean absolute error value of 9.1%. ► The present model leads to a mean absolute error value of estimate of 14.9 Wh/m 2 . - Abstract: The receiving ends of the solar energy conversion systems that generate heat or electricity from radiation is usually tilted at an optimum angle to increase the solar incident on the surface. Solar irradiation data measured on horizontal surfaces is readily available for many locations where such solar energy conversion systems are installed. Various equations have been developed to convert solar irradiation data measured on horizontal surface to that on tilted one. These equations constitute the conventional approach. In this article, an alternative approach, generalized regression type of neural network, is used to predict the solar irradiation on tilted surfaces, using the minimum number of variables involved in the physical process, namely the global solar irradiation on horizontal surface, declination and hour angles. Artificial neural networks have been successfully used in recent years for optimization, prediction and modeling in energy systems as alternative to conventional modeling approaches. To show the merit of the presently developed neural network, the solar irradiation data predicted from the novel model was compared to that from the conventional approach (isotropic and anisotropic models), with strict reference to the irradiation data measured in the same location. The present neural network model was found to provide closer solar irradiation values to the measured than the conventional approach, with a mean absolute error value of 14.9 Wh/m 2 . The other statistical values of coefficient of determination and relative mean absolute error also indicate the

  1. Production of solar radiation bankable datasets from high-resolution solar irradiance derived with dynamical downscaling Numerical Weather prediction model

    Directory of Open Access Journals (Sweden)

    Yassine Charabi

    2016-11-01

    Full Text Available A bankable solar radiation database is required for the financial viability of solar energy project. Accurate estimation of solar energy resources in a country is very important for proper siting, sizing and life cycle cost analysis of solar energy systems. During the last decade an important progress has been made to develop multiple solar irradiance database (Global Horizontal Irradiance (GHI and Direct Normal Irradiance (DNI, using satellite of different resolution and sophisticated models. This paper assesses the performance of High-resolution solar irradiance derived with dynamical downscaling Numerical Weather Prediction model with, GIS topographical solar radiation model, satellite data and ground measurements, for the production of bankable solar radiation datasets. For this investigation, NWP model namely Consortium for Small-scale Modeling (COSMO is used for the dynamical downscaling of solar radiation. The obtained results increase confidence in solar radiation data base obtained from dynamical downscaled NWP model. The mean bias of dynamical downscaled NWP model is small, on the order of a few percents for GHI, and it could be ranked as a bankable datasets. Fortunately, these data are usually archived in the meteorological department and gives a good idea of the hourly, monthly, and annual incident energy. Such short time-interval data are valuable in designing and operating the solar energy facility. The advantage of the NWP model is that it can be used for solar radiation forecast since it can estimate the weather condition within the next 72–120 hours. This gives a reasonable estimation of the solar radiation that in turns can be used to forecast the electric power generation by the solar power plant.

  2. Feasibility Study on Fiber-optic Radiation Sensor for Remote Gamma-ray Spectroscopy

    International Nuclear Information System (INIS)

    Jeon, Hyesu; Jang, Kyoung Won; Shin, Sang Hun and others

    2014-01-01

    In this study, we fabricated a fiber-optic radiation sensor using an optical fiber and various scintillators. To select an adequate inorganic scintillator for the sensing probe of fiber-optic radiation sensor, 5 types of scintillators were evaluated. The spectra of gamma-rays emitted from a Na-22 radiation source were measured by using the manufactured sensors. As a result, the BGO was suitable for the sensing probe of fiber-optic radiation sensor due to its high scintillation output and exact photoelectric peak for the gamma-ray energy. The basic principle of radiation detection is to detect the signals caused by interactions between radiations and materials. There are various types of radiation detectors depending on types of radiation to be detected and physical quantities to be measured. As one of the radiation detectors, a fiber-optic radiation sensor using a scintillator and an optical fiber has two advantages such as no space restraint and remote sensing. Moreover, in nuclear environments, this kind of sensor has immunities for electromagnetic field, temperature, and pressure. Thus, the fiber-optic radiation sensor can be used in various fields including nondestructive inspection, radioactive waste management, nuclear safety, radiodiagnosis and radiation therapy. As a fundamental study of the fiber-optic radiation sensor for remote gamma-ray spectroscopy, in this study, we fabricated a fiber-optic radiation sensor using an optical fiber and various scintillators. To select an adequate inorganic scintillator for the sensing probe of fiber-optic radiation sensor, 5 types of scintillators were evaluated. The spectra of gamma-rays emitted from a Na-22 radiation source were measured by using the manufactured sensors

  3. Radiation hard silicon sensors for the CMS tracker upgrade

    CERN Document Server

    Pohlsen, Thomas

    2013-01-01

    At an instantaneous luminosity of $5 \\times 10^{34}$ cm$^{-2}$ s$^{-1}$, the high-luminosity phase of the Large Hadron Collider (HL-LHC) is expected to deliver a total of $3\\,000$ fb$^{-1}$ of collisions, hereby increasing the discovery potential of the LHC experiments significantly. However, the radiation dose of the tracking systems will be severe, requiring new radiation hard sensors for the CMS tracker. The CMS tracker collaboration has initiated a large material investigation and irradiation campaign to identify the silicon material and design that fulfils all requirements for detectors for the HL-LHC. Focussing on the upgrade of the outer tracker region, pad sensors as well as fully functional strip sensors have been implemented on silicon wafers with different material properties and thicknesses. The samples were irradiated with a mixture of neutrons and protons corresponding to fluences as expected for the positions of detector layers in the future tracker. Different proton energies were used for irr...

  4. Energy Dependence of Proton Radiation Damage in Si-Sensors

    CERN Document Server

    AUTHOR|(CDS)2084399; Neubüser, C.

    2014-01-01

    Irradiation experiments on silicon sensors are used to mimic the radiation environment at collider experiments with the aim to forecast the change of the electrical properties of a detector with irradiation. Measurements on irradiated sensors are invaluable in choosing a material well suited for a silicon tracking detector. This is especially true for the upgraded detectors to be used in the high-luminosity phase of the LHC (HL-LHC), where silicon sensors as currently used would suffer severe loss in signal from irradiation with charged and neutral hadrons.\\\\ The CMS Tracker Collaboration has initiated irradiation studies with protons with energies ranging from 23 MeV to 23 GeV. They are often used instead of charged hadrons, their radiation induced damage to the silicon being rather similar. However, in oxygen rich silicon, NIEL violation concerning the full depletion voltage has been observed.\\\\ In this paper results from investigations on bulk defects compared to the change of the electrical properties of ...

  5. Long-term visual health risks from solar ultraviolet radiation

    International Nuclear Information System (INIS)

    Waxler, M.

    1987-01-01

    Ocular exposure to the ultraviolet radiation (UV) contained in sunlight may result in long-term visual health problems. UV plays a role in the etiology of cataracts and possibly in the etiology of visual impairments associated with solar retinopathy, retinopathy of prematurity, ocular aging, cystoid macular edema, retinitis pigmentosa, and senile macular degeneration. The exact does relationships between known UV bioeffects and these ocular problems is, however, uncertain. Thus, there are questions about the extent to which protective measures should be taken to reduce UV exposure of the eye. This paper identifies the long-term visual health problems potentially associated with ocular exposure to solar UV; proposes worst-case assumptions for the role of solar UV in these visual problems; and recommends protective measures based on damage thresholds and worst-case assumptions

  6. Effects of stratospheric perturbations on the solar radiation budget

    International Nuclear Information System (INIS)

    Luther, F.M.

    1978-04-01

    The changes in solar absorption and in local heating rates due to perturbations to O 3 and NO 2 concentrations caused by stratospheric injection of NO/sub x/ and CFM pollutants are assessed. The changes in species concentration profiles are derived from theoretical calculations using a transport-kinetics model. Because of significant changes in our understanding of stratospheric chemistry during the past year, the assessment of the effect of stratospheric perturbations on the solar radiation budget differs from previous assessments. Previously, a reduction in O 3 due to an NO/sub x/ injection caused a net decrease in the gaseous solar absorption;now the same perturbation leads to a net increase. The implication of these changes on the surface temperature is also discussed

  7. Solar radiation and out-of-hospital cardiac arrest in Japan.

    Science.gov (United States)

    Onozuka, Daisuke; Hagihara, Akihito

    2017-11-01

    Although several studies have estimated the effects of temperature on mortality and morbidity, little is known regarding the burden of out-of-hospital cardiac arrest (OHCA) attributable to solar radiation. We obtained data for all cases of OHCA and meteorological data reported between 2011 and 2014 in 3 Japanese prefectures: Hokkaido, Ibaraki, and Fukuoka. We first examined the relationship between daily solar radiation and OHCA risk for each prefecture using time-varying distributed lag non-linear models and then pooled the results in a multivariate random-effects meta-analysis. The attributable fractions of OHCA were calculated for low and high solar radiation, defined as solar radiation below and above the minimum morbidity solar radiation, respectively. The minimum morbidity solar radiation was defined as the specific solar radiation associated with the lowest morbidity risk. A total of 49,892 cases of OHCA occurred during the study period. The minimum morbidity solar radiation for each prefecture was the 100th percentile (72.5 MJ/m 2 ) in Hokkaido, the 83rd percentile (59.7 MJ/m 2 ) in Ibaraki, and the 70th percentile (53.8 MJ/m 2 ) in Fukuoka. Overall, 20.00% (95% empirical confidence interval [eCI]: 10.97-27.04) of the OHCA cases were attributable to daily solar radiation. The attributable fraction for low solar radiation was 19.50% (95% eCI: 10.00-26.92), whereas that for high solar radiation was 0.50% (95% eCI: -0.07-1.01). Low solar radiation was associated with a substantial attributable risk for OHCA. Our findings suggest that public health efforts to reduce OHCA burden should consider the solar radiation level. Large prospective studies with longitudinal collection of individual data is required to more conclusively assess the impact of solar radiation on OHCA. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Solar ultraviolet radiation response of EBT2 Gafchromic, radiochromic film

    International Nuclear Information System (INIS)

    Butson, Ethan T; Yu, Peter K N; Butson, Martin J

    2013-01-01

    Measurement of solar ultraviolet (UV) radiation is an important aspect of dosimetry for the improved knowledge of UV exposure and its associated health related issues. EBT2 Gafchromic film has been designed by its manufacturers as an improved tool for ionizing radiation dosimetry. The film is stated as exhibiting a significant reduction in UV response. However, results have shown that when exposed to UV from the ‘bottom side’ i.e. from the thick laminate side, the film exhibits a sensitivity to solar UV radiation which is both measurable and accurate for UV dosimetry. Films were irradiated in this position to known solar UV exposures and results are quantified showing a reproducibility of measurement to within ±7% (1 SD) when compared to calibrated UV meters. With an exposure of 20 J cm −2 broad spectrum solar UV, the films net OD change was found to be 0.248 OD ± 0.021 OD when analysing the results using the red channel region of an Epson V700 desktop scanner. This was compared to 0.0294 OD ± 0.0053 OD change with exposure to the same UV exposure from the top side. This means that solar UV dosimetry can be performed using EBT2 Gafchromic film utilizing the underside of the film for dosimetry. The main advantages of this film type for measurement of UV exposure is the visible colour change and thus easy analysis using a desktop scanner as well as its uniformity in response and its robust physical strength for use in outside exposure situations. (note)

  9. Spectral variation of the solar radiation during an eclipse

    Directory of Open Access Journals (Sweden)

    Peter Koepke

    2001-05-01

    Full Text Available The time dependent variation of the spectral extraterrestrial solar flux is modelled for the conditions during a total eclipse. These data are used to calculate irradiance and actinic flux at the Earth’s surface for atmospheric conditions of August 11, 1999 at Weihenstephan. These results are compared with measurements. It is shown, that the spectral composition of solar radiation varies during the eclipse, since solar limb darkening has a spectral dependence. The solar radiation differs from that of a hypothetical sun without limb darkening by up to 30% in the near IR at 1500 nm and 60% in the UV-B at 310 nm. As shown by a comparison of modelling and measurements, this spectral variation has to be taken into account for modelling of UV radiative quantities in the atmosphere and resulting photochemical processes. The effect of broken cloudiness on irradiance and actinic flux and its dependency on wavelength and receiver geometry is explained. Der Verlauf der spektralen extraterrestrischen solaren Strahlung wÄhrend einer Sonnenfinsternis wurde berechnet. Basierend auf diesen Daten, unter BerÜcksichtigung der atmosphÄrischen Bedingungen am 11. August 1999 in Weihenstephan, wurden Globalstrahlung und Aktinischer Fluss am Boden modelliert und mit Messwerten verglichen. Die spektrale Zusammensetzung der Strahlung Ändert sich wÄhrend einer Sonnenfinsternis, bedingt durch die wellenlÄngenabhÄngige Randverdunklung der Sonne. Im Vergleich zu einer hypothetischen Sonne ohne Randverdunklung ist die solare Strahlung im nahen IR um bis zu 30% gemindert und im UVB bei 310 nm um bis zu 60%. Diese spektralen Änderungen sollten bei der Modellierung von Strahlung, z.B. fÜr photochemische Prozesse berÜcksichtigt werden. Dies wurde durch Messung und Modellierung gezeigt. Der Einfluss von Wolken auf gemessene Werte von Globalstrahlung und Aktinischem Fluss wurde untersucht und erklÄrt.

  10. Photoluminescence in large fluence radiation irradiated space silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Hisamatsu, Tadashi; Kawasaki, Osamu; Matsuda, Sumio [National Space Development Agency of Japan, Tsukuba, Ibaraki (Japan). Tsukuba Space Center; Tsukamoto, Kazuyoshi

    1997-03-01

    Photoluminescence spectroscopy measurements were carried out for silicon 50{mu}m BSFR space solar cells irradiated with 1MeV electrons with a fluence exceeding 1 x 10{sup 16} e/cm{sup 2} and 10MeV protons with a fluence exceeding 1 x 10{sup 13} p/cm{sup 2}. The results were compared with the previous result performed in a relative low fluence region, and the radiation-induced defects which cause anomalous degradation of the cell performance in such large fluence regions were discussed. As far as we know, this is the first report which presents the PL measurement results at 4.2K of the large fluence radiation irradiated silicon solar cells. (author)

  11. CO2 and solar radiation: cause of global warming?

    International Nuclear Information System (INIS)

    Bayona Gabriel; Garcia, Yuri C.; Sarmiento Heiner R

    2010-01-01

    A cause-effect relationship between global temperature as a climatic change indicator and some of the main forcing mechanisms (Atmospheric CO 2 concentration, solar radiation and volcanic activity) are analyzed in this paper through time series analysis for the 1610-1990 AD period comparing trends and variability for the frequency spectrums. Temperature seems to fit the CO 2 trend for the last century, but we found no cause-effect relationship for this interval. The frequency analysis shows a correlation between radiation and temperature for a period of 22 years. Volcanism presents an inverse relationship with temperature better seen at a decadal scale.

  12. Variation of sodium on Mercury with solar radiation pressure

    International Nuclear Information System (INIS)

    Potter, A.E.; Morgan, T.H.

    1987-01-01

    It has been suggested that nonthermal Na atoms with velocities in excess of 2.1 km/sec in the Mercury atmosphere can be accelerated off the planet by solar radiation pressure; Na abundance may accordingly be expected to decrease with increasing radiation pressure. While this is confirmed by the present measurements, high resolution line profile measurements on Na emission indicate that very little, if any, of the Na is nonthermal, while the bulk is at a temperature approaching that of the planetary surface. Attention is given to explanations for the observed variation. 11 references

  13. Numerical model of solar dynamic radiator for parametric analysis

    Science.gov (United States)

    Rhatigan, Jennifer L.

    1989-01-01

    Growth power requirements for Space Station Freedom will be met through addition of 25 kW solar dynamic (SD) power modules. Extensive thermal and power cycle modeling capabilities have been developed which are powerful tools in Station design and analysis, but which prove cumbersome and costly for simple component preliminary design studies. In order to aid in refining the SD radiator to the mature design stage, a simple and flexible numerical model was developed. The model simulates heat transfer and fluid flow performance of the radiator and calculates area mass and impact survivability for many combinations of flow tube and panel configurations, fluid and material properties, and environmental and cycle variations.

  14. Convenient models of the atmosphere: optics and solar radiation

    Science.gov (United States)

    Alexander, Ginsburg; Victor, Frolkis; Irina, Melnikova; Sergey, Novikov; Dmitriy, Samulenkov; Maxim, Sapunov

    2017-11-01

    Simple optical models of clear and cloudy atmosphere are proposed. Four versions of atmospheric aerosols content are considered: a complete lack of aerosols in the atmosphere, low background concentration (500 cm-3), high concentrations (2000 cm-3) and very high content of particles (5000 cm-3). In a cloud scenario, the model of external mixture is assumed. The values of optical thickness and single scattering albedo for 13 wavelengths are calculated in the short wavelength range of 0.28-0.90 µm, with regard to the molecular absorption bands, that is simulated with triangle function. A comparison of the proposed optical parameters with results of various measurements and retrieval (lidar measurement, sampling, processing radiation measurements) is presented. For a cloudy atmosphere models of single-layer and two-layer atmosphere are proposed. It is found that cloud optical parameters with assuming the "external mixture" agrees with retrieved values from airborne observations. The results of calculating hemispherical fluxes of the reflected and transmitted solar radiation and the radiative divergence are obtained with the Delta-Eddington approach. The calculation is done for surface albedo values of 0, 0.5, 0.9 and for spectral values of the sandy surface. Four values of solar zenith angle: 0°, 30°, 40° and 60° are taken. The obtained values are compared with data of radiative airborne observations. Estimating the local instantaneous radiative forcing of atmospheric aerosols and clouds for considered models is presented together with the heating rate.

  15. Studies on the temperature distribution of steel plates with different paints under solar radiation

    International Nuclear Information System (INIS)

    Liu, Hongbo; Chen, Zhihua; Chen, Binbin; Xiao, Xiao; Wang, Xiaodun

    2014-01-01

    Thermal effects on steel structures exposed to solar radiation are significant and complicated. Furthermore, the solar radiation absorption coefficient of steel surface with different paintings is the main factor affecting the non-uniform temperature of spatial structures under solar radiation. In this paper, nearly two hundreds steel specimens with different paintings were designed and measured to obtain their solar radiation absorption coefficients using spectrophotometer. Based on the test results, the effect of surface color, painting type, painting thickness on the solar radiation absorption coefficient was analyzed. The actual temperatures under solar radiation for all specimens were also measured in summer not only to verify the absorption coefficient but also provide insight for the temperature distribution of steel structures with different paintings. A numerical simulation and simplified formula were also conducted and verified by test, in order to study the temperature distribution of steel plates with different paints under solar radiation. The results have given an important reference in the future research of thermal effect of steel structures exposed to solar radiation. - Highlights: • Solar radiation absorptions for steel with different paintings were measured. • The temperatures of all specimens under solar radiation were measured. • The effect of color, thickness and painting type on solar absorption was analyzed. • A numerical analysis was conducted and verified by test data. • A simplified formula was deduced and verified by test data

  16. Radiation hardened high efficiency silicon space solar cell

    International Nuclear Information System (INIS)

    Garboushian, V.; Yoon, S.; Turner, J.

    1993-01-01

    A silicon solar cell with AMO 19% Beginning of Life (BOL) efficiency is reported. The cell has demonstrated equal or better radiation resistance when compared to conventional silicon space solar cells. Conventional silicon space solar cell performance is generally ∼ 14% at BOL. The Radiation Hardened High Efficiency Silicon (RHHES) cell is thinned for high specific power (watts/kilogram). The RHHES space cell provides compatibility with automatic surface mounting technology. The cells can be easily combined to provide desired power levels and voltages. The RHHES space cell is more resistant to mechanical damage due to micrometeorites. Micro-meteorites which impinge upon conventional cells can crack the cell which, in turn, may cause string failure. The RHHES, operating in the same environment, can continue to function with a similar crack. The RHHES cell allows for very efficient thermal management which is essential for space cells generating higher specific power levels. The cell eliminates the need for electrical insulation layers which would otherwise increase the thermal resistance for conventional space panels. The RHHES cell can be applied to a space concentrator panel system without abandoning any of the attributes discussed. The power handling capability of the RHHES cell is approximately five times more than conventional space concentrator solar cells

  17. Rapid and extensive warming following cessation of solar radiation management

    OpenAIRE

    McCusker, Kelly E.; Armour, Kyle; Bitz, Cecilia M.; Battisti, David S.

    2014-01-01

    Solar radiation management (SRM) has been proposed as a means to alleviate the climate impacts of ongoing anthropogenic greenhouse gas (GHG) emissions. However, its efficacy depends on its indefinite maintenance, without interruption from a variety of possible sources, such as technological failure or global cooperation breakdown. Here, we consider the scenario in which SRM—via stratospheric aerosol injection—is terminated abruptly following an implementation period during which anthropogenic...

  18. Solar Radiation Data Base for Nigeria | Chineke | Discovery and ...

    African Journals Online (AJOL)

    Solar Radiation Data Base for Nigeria. T C Chineke, J I Aina, S S Jagtap. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · http://dx.doi.org/10.4314/dai.v11i3.15556 · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's ...

  19. Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Rossini, Lorenzo; The ATLAS collaboration

    2018-01-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC), the innermost layers will receive a fluence in excess of 10^15 neq/cm^2 and the HL-HLC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current and future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects to the ATLAS pixel sensors for the first time and considers both planar and 3D sensor designs. In addition to thoroughly describing the setup, we compare predictions for b...

  20. Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Rossini, Lorenzo; The ATLAS collaboration

    2018-01-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High- Luminosity LHC (HL-LHC), the innermost layers will receive a fluence in excess of 10^15 neq/cm2 and the HL-HLC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects to the ATLAS pixel sensors for the first time and considers both planar and 3D sensor designs. In addition to thoroughly describing the setup, we compare predictions for basic...

  1. Transmission coefficient of solar radiation in Manaus (AM-Brazil), in June

    International Nuclear Information System (INIS)

    Villa Nova, N.A.; Santos, J.M.; Goes Ribeiro, M.N.

    1976-01-01

    Global and diffuse solar radiation measurements, obtained by means of an Eppley pyrheliometer, were made two days in June 1975, one was clear day, (june, 11), and the other and overcast day (June, 19). The mean transmission coefficient for global and direct radiation were determined to be 0,81 and 0,70 respectively. The date on daily global solar radiation indicated that the values measured with the actinograph under estimate the real solar radiation values reaching the ground [pt

  2. Properties of solar generators with reflectors and radiators

    Science.gov (United States)

    Ebeling, W. D.; Rex, D.; Bierfischer, U.

    1980-06-01

    Radiation cooled concentrator systems using silicon and GaAs cells were studied. The principle of radiation cooling by the reflector surfaces is discussed for cylindrical parabolic reflectors (SARA), truncated hexagonal pyramids, and a small trough configuration. Beam paths, collection properties for imperfect orientation, and thermal optimization parameters were analyzed. The three concentrating systems with radiation cooling offer advantages over the plane panel and over the large trough. With silicon solar cells they exhibit considerably lower solar cell consumption per Kw and also lower mass per kW. With GaAs cells the SARA system reduces the number of solar cells needed per kW to less than 10%. Also in all other cases SARA offers the best values for alpha and F sub sol, as long as narrow angular tolerances of the panel orientation can be met. Analysis of the energy collecting properties for imperfect orientation shows the superiority of the hexagonal concentrator. This device can produce power for even large angles between the sun and the panel normal.

  3. Effects of solar ultraviolet radiation on tropical algal communities

    International Nuclear Information System (INIS)

    Santas, R.

    1989-01-01

    This study assessed some of the effects of solar ultraviolet (UV) radiation ion coral reef algal assemblages. The first part of the investigation was carried out under controlled laboratory conditions in the coral reef microcosm at the National Museum of Natural History in Washington, D.C., while a field counterpart was completed at the Smithsonian Institution's marine station on Grand Turk, Turks and Caicos Islands, in the eastern Caribbean. The study attempted to separate the effects of UV-A from those of UV-B. In the laboratory, algal turf assemblages exposed to simulated solar UV radiation produced 55.1% less biomass than assemblages that were not exposed to UV. Assemblages not exposed to UV were dominated by Ectocarpus rhodochondroides, whereas in the assemblage developing under high UV radiation, Enteromorpha prolifera and eventually Schizothrix calcicola dominated. Lower UV-B irradiances caused a proportional reduction in biomass production and had less pronounced effects on species composition. UV-A did not have any significant effects on either algal turf productivity or community structure. In the field, assemblages exposed to naturally occurring solar UV supported a biomass 40% lower than that of assemblages protected from UV-B exposure. Once again, UV-A did not inhibit algal turf productivity

  4. Study on Pyroelectric Harvesters Integrating Solar Radiation with Wind Power

    Directory of Open Access Journals (Sweden)

    Chun-Ching Hsiao

    2015-07-01

    Full Text Available Pyroelectric harvesters use temperature fluctuations to generate electrical outputs. Solar radiation and waste heat are rich energy sources that can be harvested. Pyroelectric energy converters offer a novel and direct energy-conversion technology by transforming time-dependent temperatures directly into electricity. Moreover, the great challenge for pyroelectric energy harvesting lies in finding promising temperature variations or an alternating thermal loading in real situations. Hence, in this article, a novel pyroelectric harvester integrating solar radiation with wind power by the pyroelectric effect is proposed. Solar radiation is a thermal source, and wind is a dynamic potential. A disk generator is used for harvesting wind power. A mechanism is considered to convert the rotary energy of the disk generator to drive a shutter for generating temperature variations in pyroelectric cells using a planetary gear system. The optimal period of the pyroelectric cells is 35 s to harvest the stored energy, about 70 μJ, while the rotary velocity of the disk generator is about 31 RPM and the wind speed is about 1 m/s. In this state, the stored energy acquired from the pyroelectric harvester is about 75% more than that from the disk generator. Although the generated energy of the proposed pyroelectric harvester is less than that of the disk generator, the pyroelectric harvester plays a complementary role when the disk generator is inactive in situations of low wind speed.

  5. Global solar radiation estimation in Lavras region, Minas Gerais

    International Nuclear Information System (INIS)

    Dantas, A.A.A.; Carvalho, L.G. de; Ferreira, E.

    2003-01-01

    The objective of this work was the determination of the ''a'' and '' b'' constants of the Angstrom linear model in order to estimate the global solar radiation in Lavras, MG. The work was carried out in the Climatological Station of Lavras (ECP/INMET/UFLA), at the Federal University of Lavras, from December 2001 to November 2002, through insolation daily data and global solar radiation daily records. The ''a'' and '' b'' constants, that express the atmospheric transmitance, were obtained by regression analysis of those data. The obtained equation, Qg/Qt = 0,23 + 0,49 presented a determination coefficient of 0,89. The results are smaller than those suggested by the recommendations that uses the local latitude. According to the results, its possible to indicate the values of 0,23 and 0,49 to be used as the ''a'' and '' b'' constants on the Angstrom equation to estimate the global solar radiation in Lavras, MG. (author) [pt

  6. Solar radiation modelling using ANNs for different climates in China

    International Nuclear Information System (INIS)

    Lam, Joseph C.; Wan, Kevin K.W.; Yang, Liu

    2008-01-01

    Artificial neural networks (ANNs) were used to develop prediction models for daily global solar radiation using measured sunshine duration for 40 cities covering nine major thermal climatic zones and sub-zones in China. Coefficients of determination (R 2 ) for all the 40 cities and nine climatic zones/sub-zones are 0.82 or higher, indicating reasonably strong correlation between daily solar radiation and the corresponding sunshine hours. Mean bias error (MBE) varies from -3.3 MJ/m 2 in Ruoqiang (cold climates) to 2.19 MJ/m 2 in Anyang (cold climates). Root mean square error (RMSE) ranges from 1.4 MJ/m 2 in Altay (severe cold climates) to 4.01 MJ/m 2 in Ruoqiang. The three principal statistics (i.e., R 2 , MBE and RMSE) of the climatic zone/sub-zone ANN models are very close to the corresponding zone/sub-zone averages of the individual city ANN models, suggesting that climatic zone ANN models could be used to estimate global solar radiation for locations within the respective zones/sub-zones where only measured sunshine duration data are available. (author)

  7. Prediction of Global Solar Radiation in India Using Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Rajiv Gupta

    2016-06-01

    Full Text Available Increasing global warming and decreasing fossil fuel reserves has necessitated the use of renewable energy resources like solar energy in India. To maximize return on a solar farm, it had to be set up at a place with high solar radiation. The solar radiation values are available only for a small number of places and must be interpolated for the rest. This paper utilizes Artificial Neural Network in interpolation, by obtaining a function with input as combinations of 7 geographical and meteorological parameters affecting radiation, and output as global solar radiation. Data considered was of past 9 years for 13 Indian cities. Low error values and high coefficient of determination values thus obtained, verified that the results were accurate in terms of the original solar radiation data known. Thus, artificial neural network can be used to interpolate the solar radiation for the places of interest depending on the availability of the data.

  8. Lessons learned on solar powered wireless sensor network deployments in urban, desert environments

    KAUST Repository

    Dehwah, Ahmad H.

    2015-05-01

    The successful deployment of a large scale solar powered wireless sensor network in an urban, desert environment is a very complex task. Specific cities of such environments cause a variety of operational problems, ranging from hardware faults to operational challenges, for instance due to the high variability of solar energy availability. Even a seemingly functional sensor network created in the lab does not guarantee reliable long term operation, which is absolutely necessary given the cost and difficulty of accessing sensor nodes in urban environments. As part of a larger traffic flow wireless sensor network project, we conducted several deployments in the last two years to evaluate the long-term performance of solar-powered urban wireless sensor networks in a desert area. In this article, we share our experiences in all domains of sensor network operations, from the conception of hardware to post-deployment analysis, including operational constraints that directly impact the software that can be run. We illustrate these experiences using numerous experimental results, and present multiple unexpected operational problems as well as some possible solutions to address them. We also show that current technology is far from meeting all operational constraints for these demanding applications, in which sensor networks are to operate for years to become economically appealing.

  9. Solar Radiation and Cloud Radiative Forcing in the Pacific Warm Pool Estimated Using TOGA COARE Measurements

    Science.gov (United States)

    Chou, Ming-Dah; Chou, Shu-Hsien; Zhao, Wenzhong

    1999-01-01

    The energy budget of the tropical western Pacific (TWP) is particularly important because this is one of the most energetic convection regions on the Earth. Nearly half of the solar radiation incident at the top of atmosphere is absorbed at the surface and only about 22% absorbed in the atmosphere. A large portion of the excess heat absorbed at the surface is transferred to the atmosphere through evaporation, which provides energy and water for convection and precipitation. The western equatorial Pacific is characterized by the highest sea surface temperature (SST) and heaviest rainfall in the world ocean. A small variation of SST associated with the eastward shift of the warm pool during El-Nino/Souther Oscillation changes the atmospheric circulation pattern and affects the global climate. In a study of the TWP surface heat and momentum fluxes during the Tropical Ocean and Global Atmosphere Coupled Ocean-Atmosphere Response Experiment (TOGA COARE) Intensive observing period (IOP) from November 1992 to February have found that the solar radiation is the most important component of the surface energy budget, which undergoes significant temporal and spatial variation. The variations are influenced by the two 40-50 days Madden Julian Oscillations (MJOs) which propagated eastward from the Indian Ocean to the Central Pacific during the IOP. The TWP surface solar radiation during the COARE IOP was investigated by a number of studies. In addition, the effects of clouds on the solar heating of the atmosphere in the TWP was studied using energy budget analysis. In this study, we present some results of the TWP surface solar shortwave or SW radiation budget and the effect of clouds on the atmospheric solar heating using the surface radiation measurements and Japan's Geostationary Meteorological Satellite 4 radiance measurements during COARE IOP.

  10. Solar radiation as a forest management tool: a primer of principles and application

    Science.gov (United States)

    Howard G. Halverson; James L. Smith

    1979-01-01

    Forests are products of solar radiation use. The sun also drives the hydrologic cycle on forested watersheds. Some basic concepts of climatology and solar radiation are summarized in including earth-sun relations, polar tilt, solar energy, terrestrial energy, energy balance, and local energy. An example shows how these principles can be applied in resource management....

  11. Slowly varying component of extreme ultraviolet solar radiation and its relation to solar radio radiation

    Science.gov (United States)

    Chapman, R. D.; Neupert, W. M.

    1974-01-01

    A study of the correlations between solar EUV line fluxes and solar radio fluxes has been carried out. A calibration for the Goddard Space Flight Center EUV spectrum is suggested. The results are used to obtain an equation for the absolute EUV flux for several lines in the 150- to 400-A region and the total flux of 81 intense lines in the region, the 2800-MHz radio flux being used as independent variable.

  12. Vulnerability of OFDR-based distributed sensors to radiations

    Energy Technology Data Exchange (ETDEWEB)

    Rizzolo, S. [Laboratoire Hubert Curien, Universite Jean Monnet, CNRS UMR 5516, 18 Rue Benoit Lauras, 42000, Saint-Etienne (France); Dipartimento di Fisica e Chimica, Universita di Palermo, Viale delle Scienze Parco d' Orleans II, Ed. 17, 90128 Palermo (Italy); Areva Centre Technique, Boulevard de l' Industrie, 71200, Le Creusot (France); Boukenter, A.; Marin, E.; Ouerdane, Y.; Girard, S. [Laboratoire Hubert Curien, Universite Jean Monnet, CNRS UMR 5516, 18 Rue Benoit Lauras, 42000, Saint-Etienne (France); Cannas, M. [Dipartimento di Fisica e Chimica, Universita di Palermo, Viale delle Scienze Parco d' Orleans II, Ed. 17, 90128 Palermo (Italy); Perisse, J. [Areva NP, 10 Rue Juliette Recamier, 69006, Lyon (France); Bauer, S. [Areva Centre Technique, Boulevard de l' Industrie, 71200, Le Creusot (France); Mace, J.R. [Areva NP, 1, Place Jean-Millier 92084, Paris-La Defense (France)

    2015-07-01

    overcome the issues identified for next generation of NPPs. Such integration will only be possible if the OFDR based systems are able to resist to the constraints associated with industrial environments, one of the most constraining being the presence of high level of radiations. In this work, we carry out a systematic study to highlight the OFDR interest and sensitivity to probe the optical samples at high irradiation dose levels. The responses of five optical fibers types, from radiation hardened to radiation sensitive ones, are investigated to explore the influence of both the material compositions and the γ-irradiation on the ODFR sensors. Using these samples, we should highlight the influence of the core dopant concentration on the observed radiation-induced changes as well as the difference observed when the cladding is either radiation resistant or radiation sensitive. Our samples were irradiated using a {sup 60}Co source facility reaching total doses varying from 1 MGy up to a maximum of 10 MGy. All the measurements are performed after diverse months from irradiation to study permanents effects induced from these high γ-rays doses. We'll present at the conference all the experimental results acquired and use them to estimate the potential of OFDR-based systems for operation in radiation environments. (authors)

  13. Effective aerosol optical depth from pyranometer measurements of surface solar radiation (global radiation) at Thessaloniki, Greece

    OpenAIRE

    Lindfors, A. V.; Kouremeti, N.; Arola, A.; Kazadzis, S.; Bais, A. F.; Laaksonen, A.

    2013-01-01

    Pyranometer measurements of the solar surface radiation (SSR) are available at many locations worldwide, often as long time series covering several decades into the past. These data constitute a potential source of information on the atmospheric aerosol load. Here, we present a method for estimating the aerosol optical depth (AOD) using pyranometer measurements of the SSR together with total water vapor column information. The method, which is based on radiative transfer simulations, w...

  14. Radiation Resistance Test of Wireless Sensor Node and the Radiation Shielding Calculation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Liqan; Sur, Bhaskar [Atomic Energy of Canada Limited, Ontario (Canada); Wang, Quan [University of Western Ontario, Ontario (Canada); Deng, Changjian [The University of Electronic Science and Technology, Chengdu (China); Chen, Dongyi; Jiang, Jin [Applied Physics Branch, Ontario (Korea, Republic of)

    2014-08-15

    A wireless sensor network (WSN) is being developed for nuclear power plants. Amongst others, ionizing radiation resistance is one essential requirement for WSN to be successful. This paper documents the work done in Chalk River Laboratories of Atomic Energy of Canada Limited (AECL) to test the resistance to neutron and gamma radiation of some WSN nodes. The recorded dose limit that the nodes can withstand before being damaged by the radiation is compared with the radiation environment inside a typical CANDU (CANada Deuterium Uranium) power plant reactor building. Shielding effects of polyethylene, cadmium and lead to neutron and gamma radiations are also analyzed using MCNP simulation. The shielding calculation can be a reference for the node case design when high dose rate or accidental condition (like Fukushima) is to be considered.

  15. Numerical simulation of thermal behaviors of a clothed human body with evaluation of indoor solar radiation

    International Nuclear Information System (INIS)

    Mao, Aihua; Luo, Jie; Li, Yi

    2017-01-01

    Highlights: • Solar radiation evaluation is integrated with the thermal transfer in clothed humans. • Thermal models are developed for clothed humans exposed in indoor solar radiation. • The effect of indoor solar radiation on humans can be predicted in different situations in living. • The green solar energy can be efficiently utilized in the building development. - Abstract: Solar radiation is a valuable green energy, which is important in achieving a successful building design for thermal comfort in indoor environment. This paper considers solar radiation indoors into the transient thermal transfer models of a clothed human body and offers a new numerical method to analyze the dynamic thermal status of a clothed human body under different solar radiation incidences. The evaluation model of solar radiation indoors and a group of coupled thermal models of the clothed human body are developed and integrated. The simulation capacities of these integrated models are validated through a comparison between the predicted results and the experimental data in reference. After that, simulation cases are also conducted to show the influence of solar radiation on the thermal status of individual clothed body segments when the human body is staying indoors in different seasons. This numerical simulation method provides a useful tool to analyze the thermal status of clothed human body under different solar radiation incidences indoors and thus enables the architect to efficiently utilize the green solar energy in building development.

  16. Effect of solar radiation on severity of soybean rust.

    Science.gov (United States)

    Young, Heather M; George, Sheeja; Narváez, Dario F; Srivastava, Pratibha; Schuerger, Andrew C; Wright, David L; Marois, James J

    2012-08-01

    Soybean rust (SBR), caused by Phakopsora pachyrhizi, is a damaging fungal disease of soybean (Glycine max). Although solar radiation can reduce SBR urediniospore survival, limited information is available on how solar radiation affects SBR progress within soybean canopies. Such information can aid in developing accurate SBR prediction models. To manipulate light penetration into soybean canopies, structures of shade cloth attenuating 30, 40, and 60% sunlight were constructed over soybean plots. In each plot, weekly evaluations of severity in lower, middle, and upper canopies, and daily temperature and relative humidity were recorded. Final plant height and leaf area index were also recorded for each plot. The correlation between amount of epicuticular wax and susceptibility of leaves in the lower, middle, and upper canopies was assessed with a detached leaf assay. Final disease severity was 46 to 150% greater in the lower canopy of all plots and in the middle canopy of 40 and 60% shaded plots. While daytime temperature within the canopy of nonshaded soybean was greater than shaded soybean by 2 to 3°C, temperatures recorded throughout typical evenings and mornings of the growing season in all treatments were within the range (10 to 28.5°C) for SBR development as was relative humidity. This indicates temperature and relative humidity were not limiting factors in this experiment. Epicuticular wax and disease severity in detached leaf assays from the upper canopy had significant negative correlation (P = 0.009, R = -0.84) regardless of shade treatment. In laboratory experiments, increasing simulated total solar radiation (UVA, UVB, and PAR) from 0.15 to 11.66 MJ m(-2) increased mortality of urediniospores from 2 to 91%. Variability in disease development across canopy heights in early planted soybean may be attributed to the effects of solar radiation not only on urediniospore viability, but also on plant height, leaf area index, and epicuticular wax, which influence

  17. Mercury Conditions for the MESSENGER Mission Simulated in High- Solar-Radiation Vacuum Tests

    Science.gov (United States)

    Wong, Wayne A.

    2003-01-01

    The MESSENGER (Mercury Surface, Space Environment, Geochemistry, and Ranging) spacecraft, planned for launch in March 2004, will perform two flybys of Mercury before entering a year-long orbit of the planet in September 2009. The mission will provide opportunities for detailed characterization of the surface, interior, atmosphere, and magnetosphere of the closest planet to the Sun. The NASA Glenn Research Center and the MESSENGER spacecraft integrator, the Johns Hopkins University Applied Physics Laboratory, have partnered under a Space Act Agreement to characterize a variety of critical components and materials under simulated conditions expected near Mercury. Glenn's Vacuum Facility 6, which is equipped with a solar simulator, can simulate the vacuum and high solar radiation anticipated in Mercury orbit. The MESSENGER test hardware includes a variety of materials and components that are being characterized during the Tank 6 vacuum tests, where the hardware will be exposed to up to 11 suns insolation, simulating conditions expected in Mercury orbit. In 2002, ten solar vacuum tests were conducted, including beginning of life, end of life, backside exposure, and solar panel thermal shock cycling tests. Components tested include candidate solar array panels, sensors, thermal shielding materials, and communication devices. As an example, for the solar panel thermal shock cycling test, two candidate solar array panels were suspended on a lift mechanism that lowered the panels into a liquid-nitrogen-cooled box. After reaching -140 C, the panels were then lifted out of the box and exposed to the equivalent of 6 suns (8.1 kilowatts per square meters). After five cold soak/heating cycles were completed successfully, there was no apparent degradation in panel performance. An anticipated 100-hr thermal shield life test is planned for autumn, followed by solar panel flight qualification tests in winter. Glenn's ongoing support to the MESSENGER program has been instrumental in

  18. Photocatalysis and radiation absorption in a solar plant

    Energy Technology Data Exchange (ETDEWEB)

    Curco, D; Gimenez, J [Departamento de Ingenieria Quimica, Facultad de Quimica, Universidad de Barcelona, Barcelona (Spain); Malato, S; Blanco, J [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Plataforma Solar de Almeria, Almeria (Spain)

    1996-11-15

    Recently, many papers have appeared in literature about photocatalytic detoxification. However, progress from laboratory data to the industrial solar reactor is not easy. Kinetic models for heterogeneous catalysis can be used to describe the photocatalytic processes, but luminic steps, related to the radiation, have to be added to the physical and chemical steps considered in heterogeneous catalysis. Thus, the evaluation of the radiation, and its distribution, inside a photocatalytic reactor is essential to extrapolate results from laboratory to outdoor experiments and to compare the efficiency of different installations. This study attempts to validate the experimental set up and theoretical data treatment for this purpose in a Solar Pilot Plant. The procedure consists of the calibration of different sunlight radiometers, the estimation of the radiation inside the reactor, and the validation of the results by actinometric experiments. Finally, a comparison between kinetic constants, for the same reaction in the laboratory (artificial light) and field conditions (sun light), is performed to demonstrate the advantages of knowing the radiation inside a large photochemical reactor

  19. Measuring solar UV radiation with EBT radiochromic film

    International Nuclear Information System (INIS)

    Butson, Ethan T; Cheung Tsang; Yu, Peter K N; Butson, Martin J

    2010-01-01

    Ultraviolet radiation dosimetry has been performed with the use of a radiochromic film dosimeter called Gafchromic EBT for solar radiation exposure. The film changes from a clear colour to blue colour when exposed to ultraviolet radiation and results have shown that the colour change is reproducible within ±10% at 5 kJ m -2 UV exposure under various conditions of solar radiation. Parameters tested included changes in season (summer versus winter exposure), time of day, as well as sky conditions such as cloudy skies versus clear skies. As the radiochromic films' permanent colour change occurs in the visible wavelengths the film can be analysed with a desktop scanner with the most sensitive channel for analysis being the red component of the signal. Results showed that an exposure of 5 kJ m -2 (approximately 1 h exposure in full sun during summer) produced an approximate 0.28 change in the net OD when analysed in reflection mode on the desktop scanner which is significant darkening. The main advantages of this film type, and thus the new EBT2 film which has replaced EBT for measurement of UV exposure, is the visible colour change and thus easy analysis using a desktop scanner, its uniformity in response and its robust physical strength for use in outside exposure situations. (note)

  20. Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Nachman, Benjamin Philip; The ATLAS collaboration

    2017-01-01

    Silicon Pixel detectors are at the core of the current and planned upgrade of the ATLAS detector. As the detector in closest proximity to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the HL-LHC, the innermost layers will receive a fluence in excess of $10^{15}$ 1 MeV $n_\\mathrm{eq}/\\mathrm{cm}^2$ and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. This talk presents a digitization model that includes radiation damage effects to the ATLAS Pixel sensors for the first time. After a thorough description of the setup, predictions for basic Pixel cluster properties are presented alongside first validation studies with Run 2 collision data.

  1. Chalcogenide Glass Radiation Sensor; Materials Development, Design and Device Testing

    Energy Technology Data Exchange (ETDEWEB)

    Mitkova, Maria; Butt, Darryl; Kozicki, Michael; Barnaby, Hugo

    2013-04-30

    studied the effect of x-rays and γ-rays, on thin film chalcogenide glasses and applied them in conjunction with film incorporating a silver source in a new type of radiation sensor for which we have an US patent application [3]. In this report, we give data about our studies regarding our designed radiation sensor along with the testing and performance at various radiation doses. These studies have been preceded by materials characterization research related to the compositional and structural characteristics of the active materials used in the radiation sensor design. During the work on the project, we collected a large volume of material since every experiment was repeated many times to verify the results. We conducted a comprehensive material research, analysis and discussion with the aim to understand the nature of the occurring effects, design different structures to harness these effects, generated models to aid in the understanding the effects, built different device structures and collected data to quantify device performance. These various aspects of our investigation have been detailed in previous quarterly reports. In this report, we present our main results and emphasize on the results pertaining to the core project goals materials development, sensor design and testing and with an emphasis on classifying the appropriate material and design for the optimal application. The report has three main parts: (i) Presentation of the main data; (ii) Bulleted summary of the most important results; (iii) List of the patent, journal publications, conference proceedings and conferences participation, occurring as a result of working on the project.

  2. 1999-2003 Shortwave Characterizations of Earth Radiation Budget Satellite (ERBS)/Earth Radiation Budget Experiment (ERBE) Broadband Active Cavity Radiometer Sensors

    Science.gov (United States)

    Lee, Robert B., III; Smith, George L.; Wong, Takmeng

    2008-01-01

    From October 1984 through May 2005, the NASA Earth Radiation Budget Satellite (ERBS/ )/Earth Radiation Budget Experiment (ERBE)ERBE nonscanning active cavity radiometers (ACR) were used to monitor long-term changes in the earth radiation budget components of the incoming total solar irradiance (TSI), earth-reflected TSI, and earth-emitted outgoing longwave radiation (OLR). From September1984 through September 1999, using on-board calibration systems, the ERBS/ERBE ACR sensor response changes, in gains and offsets, were determined from on-orbit calibration sources and from direct observations of the incoming TSI through calibration solar ports at measurement precision levels approaching 0.5 W/sq m , at satellite altitudes. On October 6, 1999, the onboard radiometer calibration system elevation drive failed. Thereafter, special spacecraft maneuvers were performed to observe cold space and the sun in order to define the post-September 1999 geometry of the radiometer measurements, and to determine the October 1999-September 2003 ERBS sensor response changes. Analyses of these special solar and cold space observations indicate that the radiometers were pointing approximately 16 degrees away from the spacecraft nadir and on the anti-solar side of the spacecraft. The special observations indicated that the radiometers responses were stable at precision levels approaching 0.5 W/sq m . In this paper, the measurement geometry determinations and the determinations of the radiometers gain and offset are presented, which will permit the accurate processing of the October 1999 through September 2003 ERBE data products at satellite and top-of-the-atmosphere altitudes.

  3. Effects of solar UV-B radiation on aquatic ecosystems

    Science.gov (United States)

    Häder, D.-P.

    Solar UV degrades dissolved organic carbon photolytically so that they can readily be taken up by bacterioplankton. On the other hand solar UV radiation inhibits bacterioplankton activity. Bacterioplankton productivity is far greater than previously thought and is comparable to phytoplankton primary productivity. According to the "microbial loop hypothesis," bacterioplankton is seen in the center of a food web, having a similar function to phytoplankton and protists. The penetration of UV and PAR into the water column can be measured. Marine waters show large temporal and regional differences in their concentrations of dissolved and particulate absorbing substances. A network of dosimeters (ELDONET) has been installed in Europe ranging from Abisko in Northern Sweden to Gran Canaria. Cyanobacteria are capable of fixing atmospheric nitrogen which is then made available to higher plants. The agricultural potential of cyanobacteria has been recognized as a biological fertilizer for wet soils such as in rice paddies. UV-B is known to impair processes such as growth, survival, pigmentation, motility, as well as the enzymes of nitrogen metabolism and CO 2 fixation. The marine phytoplankton represents the single most important ecosystem on our planet and produces about the same biomass as all terrestrial ecosystems taken together. It is the base of the aquatic food chain and any changes in the size and composition of phytoplankton communities will directly affect food production for humans from marine sources. Another important role of marine phytoplankton is to serve as a sink for atmospheric carbon dioxide. Recent investigations have shown a large sensitivity of most phytoplankton organisms toward solar short-wavelength ultraviolet radiation (UV-B); even at ambient levels of UV-B radiation many organisms seem to be under UV stress. Because of their requirement for solar energy, the phytoplankton dwell in the top layers of the water column. In this near-surface position

  4. Comparative study of series of solar radiation; Estudio comparativo de series de radiacion solar

    Energy Technology Data Exchange (ETDEWEB)

    Adaro, Agustin; Cesari, Daniela; Lema, Alba; Galimberti, Pablo; Barral, Jorge [Universidad Nacional de Rio Cuarto, (Argentina)

    2000-07-01

    In any team or solar device that it seeks to be designed and dedicated to the use of the solar energy it will be had the most appropriate information on the radiation levels. Being this source of dependent energy of the atmospheric and meteorological fluctuations, it is that requires have the information best regarding the quantity and variability of the available solar energy. A road is already the statistical treatment of the data available, so much of solar radiation as of hours of sun. This focus generates a lot of expectation for the biggest quantity in information regarding the hours of existent sun. This bigger information of hours of sun is due to that the mensurations are carried out with instruments called heliografos with a level of complexity and much smaller cost that the instruments of radiation mensuration. Among the heliografos the most used one is that of Campbell-Stokes, and it is the one that you had installed in most of the meteorological stations of Argentina and the World, for what the information of hours of sun is the one that more is plentiful. The present work has for objective to find an interrelation between the measured series of hours of sun and irradiation. The study is carried out using models of temporary series and the pattern of Angstrom-Page. The are carried out a study of the generation of radiation sequences using models of temporary series and the pattern of Angstrom-Page. They are carried out a study of the generation of radiation sequences using the concept of the Chains of Markov. Rio Cuarto's series are analyzed for being determined the transfer function among both series, and the values of global solar radiation are obtained for towns of the same region. They are the coefficients of Anstrom-Page's Equation for Rio Cuarto. They are the values monthly means for these two methods and results are compared. [Spanish] En cualquier equipo o dispositivo solar que pretenda ser disenado y destinado al aprovechamiento de

  5. Optically pumped carbon dioxide laser mixtures. [using solar radiation

    Science.gov (United States)

    Yesil, O.; Christiansen, W. H.

    1979-01-01

    This work explores the concept of blackbody radiation pumping of CO2 gas as a step toward utilization of solar radiation as a pumping source for laser action. To demonstrate this concept, an experiment was performed in which laser gas mixtures were exposed to 1500 K thermal radiation for brief periods of time. A gain of 2.8 x 10 to the -3rd reciprocal centimeters has been measured at 10.6 microns in a CO2-He gas mixture of 1 Torr pressure. A simple analytical model is used to describe the rate of change of energy of the vibrational modes of CO2 and to predict the gain. Agreement between the prediction and experiment is good.

  6. A Distributed Routing Scheme for Energy Management in Solar Powered Sensor Networks

    KAUST Repository

    Dehwah, Ahmad H.

    2017-10-11

    Energy management is critical for solar-powered sensor networks. In this article, we consider data routing policies to optimize the energy in solar powered networks. Motivated by multipurpose sensor networks, the objective is to find the best network policy that maximizes the minimal energy among nodes in a sensor network, over a finite time horizon, given uncertain energy input forecasts. First, we derive the optimal policy in certain special cases using forward dynamic programming. We then introduce a greedy policy that is distributed and exhibits significantly lower complexity. When computationally feasible, we compare the performance of the optimal policy with the greedy policy. We also demonstrate the performance and computational complexity of the greedy policy over randomly simulated networks, and show that it yields results that are almost identical to the optimal policy, for greatly reduced worst-case computational costs and memory requirements. Finally, we demonstrate the implementation of the greedy policy on an experimental sensor network.

  7. Control con dos sensores para energías eólica y solar; Control with two sensors for energies wind and solar

    Directory of Open Access Journals (Sweden)

    Alfredo G M Gámez López

    2011-02-01

    Full Text Available En el artículo se realiza un análisis de dos sensores que se aplican en energías renovables (eólica y solar,obteniéndose una ley de control óptima. Para las fuentes energéticas elegidas se proponen técnicas de altafrecuencia de conmutación y eficiencia. Para la validación de los resultados se emplean técnicas desimulación digital In this article we make an analysis of two sensors applied in renewable energies (wind and solar,obtaining an ideal law of control. For the chosen energetic sources there appear technologies of highfrequency of commutation and of high efficiency. Technologies of digital simulation validate the results.

  8. Three-dimensional transfer of solar radiation in clouds

    International Nuclear Information System (INIS)

    Davies, R.

    1976-01-01

    The results of a theoretical study of the effects of cloud geometry on the transfer of incident solar radiation is presented. These results indicate that a three-dimensional description of cloud geometry is a necessary prerequisite to the accurate determination of the emerging radiation field. Models which make the plane parallel assumption are therefore frequently inadequate. Both a Monte Carlo method and an analytic method were used to model the three-dimensional transfer of radiation. At the expense of considerable computation time the Monte Carlo model provides accurate values of the fluxes and intensities (averages over π/30 steradians) emerging from clouds which can be described as a set of connected cuboidal cells, each cell being homogeneous with respect to extinction coefficient, single scatter albedo and phase function. The analytic model, based on an extension of Eddington's approximation to three dimensions and to anisotropic scattering, is efficient to use, but is restricted to clouds made up of a single cuboidal cell and is more accurate for large clouds than small ones. By an iterated approach, involving integration of the source function along line of sight, the analytic model provides both fluxes and intensities of the emerging radiation at any specified point on the cloud's surface. These models were both applied to a systematic study of the transfer of solar radiation in isolated cuboidal clouds of arbitraty dimensions, the results of which illustrate the importance of considering the total cloud geometry in any attempt at realistic modelling. A study of the transfer of radiation in stratiform clouds with turretted top surfaces also indicated that even for these clouds the plane parallel assumption was often not tenable

  9. Radiation Belt Transport Driven by Solar Wind Dynamic Pressure Fluctuations

    Science.gov (United States)

    Kress, B. T.; Hudson, M. K.; Ukhorskiy, A. Y.; Mueller, H.

    2012-12-01

    The creation of the Earth's outer zone radiation belts is attributed to earthward transport and adiabatic acceleration of electrons by drift-resonant interactions with electromagnetic fluctuations in the magnetosphere. Three types of radial transport driven by solar wind dynamic pressure fluctuations that have been identified are: (1) radial diffusion [Falthammer, 1965], (2) significant changes in the phase space density radial profile due to a single or few ULF drift-resonant interactions [Ukhorskiy et al., 2006; Degeling et al., 2008], and (3) shock associated injections of radiation belt electrons occurring in less than a drift period [Li et al., 1993]. A progress report will be given on work to fully characterize different forms of radial transport and their effect on the Earth's radiation belts. The work is being carried out by computing test-particle trajectories in electric and magnetic fields from a simple analytic ULF field model and from global MHD simulations of the magnetosphere. Degeling, A. W., L. G. Ozeke, R. Rankin, I. R. Mann, and K. Kabin (2008), Drift resonant generation of peaked relativistic electron distributions by Pc 5 ULF waves, textit{J. Geophys. Res., 113}, A02208, doi:10.1029/2007JA012411. Fälthammar, C.-G. (1965), Effects of Time-Dependent Electric Fields on Geomagnetically Trapped Radiation, J. Geophys. Res., 70(11), 2503-2516, doi:10.1029/JZ070i011p02503. Li, X., I. Roth, M. Temerin, J. R. Wygant, M. K. Hudson, and J. B. Blake (1993), Simulation of the prompt energization and transport of radiation belt particles during the March 24, 1991 SSC, textit{Geophys. Res. Lett., 20}(22), 2423-2426, doi:10.1029/93GL02701. Ukhorskiy, A. Y., B. J. Anderson, K. Takahashi, and N. A. Tsyganenko (2006), Impact of ULF oscillations in solar wind dynamic pressure on the outer radiation belt electrons, textit{Geophys. Res. Lett., 33}(6), L06111, doi:10.1029/2005GL024380.

  10. Fully Integrated Solar Energy Harvester and Sensor Interface Circuits for Energy-Efficient Wireless Sensing Applications

    Directory of Open Access Journals (Sweden)

    Maher Kayal

    2013-02-01

    Full Text Available This paper presents an energy-efficient solar energy harvesting and sensing microsystem that harvests solar energy from a micro-power photovoltaic module for autonomous operation of a gas sensor. A fully integrated solar energy harvester stores the harvested energy in a rechargeable NiMH microbattery. Hydrogen concentration and temperature are measured and converted to a digital value with 12-bit resolution using a fully integrated sensor interface circuit, and a wireless transceiver is used to transmit the measurement results to a base station. As the harvested solar energy varies considerably in different lighting conditions, in order to guarantee autonomous operation of the sensor, the proposed area- and energy-efficient circuit scales the power consumption and performance of the sensor. The power management circuit dynamically decreases the operating frequency of digital circuits and bias currents of analog circuits in the sensor interface circuit and increases the idle time of the transceiver under reduced light intensity. The proposed microsystem has been implemented in a 0.18 µm complementary metal-oxide-semiconductor (CMOS process and occupies a core area of only 0.25 mm2. This circuit features a low power consumption of 2.1 µW when operating at its highest performance. It operates with low power supply voltage in the 0.8V to 1.6 V range.

  11. Radiation sensors based on GaN microwires

    Science.gov (United States)

    Verheij, D.; Peres, M.; Cardoso, S.; Alves, L. C.; Alves, E.; Durand, C.; Eymery, J.; Lorenz, K.

    2018-05-01

    GaN microwires were shown to possess promising characteristics as building blocks for radiation resistant particle detectors. They were grown by metal organic vapour phase epitaxy with diameters between 1 and 2 μm and lengths around 20 μm. Devices were fabricated by depositing gold contacts at the extremities of the wires using photolithography. The response of these single wire radiation sensors was then studied under irradiation with 2 MeV protons. Severe degradation of the majority of devices only sets in for fluences above protons cm‑2 revealing good radiation resistance. During proton irradiation, a clear albeit small current gain was observed with a corresponding decay time below 1 s. Photoconductivity measurements upon irradiation with UV light were carried out before and after the proton irradiation. Despite a relatively low gain, attributed to significant dark currents caused by a high dopant concentration, fast response times of a few seconds were achieved comparable to state-of-the-art GaN nanowire photodetectors. Irradiation and subsequent annealing resulted in an overall improvement of the devices regarding their response to UV radiation. The photocurrent gain increased compared to the values that were obtained prior to the irradiation, without compromising the decay times. The results indicate the possibility of using GaN microwires not only as UV detectors, but also as particle detectors.

  12. [Comparison of three daily global solar radiation models].

    Science.gov (United States)

    Yang, Jin-Ming; Fan, Wen-Yi; Zhao, Ying-Hui

    2014-08-01

    Three daily global solar radiation estimation models ( Å-P model, Thornton-Running model and model provided by Liu Ke-qun et al.) were analyzed and compared using data of 13 weather stations from 1982 to 2012 from three northeastern provinces and eastern Inner Mongolia. After cross-validation analysis, the result showed that mean absolute error (MAE) for each model was 1.71, 2.83 and 1.68 MJ x m(-2) x d(-1) respectively, showing that Å-P model and model provided by Liu Ke-qun et al. which used percentage of sunshine had an advantage over Thornton-Running model which didn't use percentage of sunshine. Model provided by Liu Ke-qun et al. played a good effect on the situation of non-sunshine, and its MAE and bias percentage were 18.5% and 33.8% smaller than those of Å-P model, respectively. High precision results could be obtained by using the simple linear model of Å-P. Å-P model, Thornton-Running model and model provided by Liu Ke-qun et al. overvalued daily global solar radiation by 12.2%, 19.2% and 9.9% respectively. MAE for each station varied little with the spatial change of location, and annual MAE decreased with the advance of years. The reason for this might be that the change of observation accuracy caused by the replacement of radiation instrument in 1993. MAEs for rainy days, non-sunshine days and warm seasons of the three models were greater than those for days without rain, sunshine days and cold seasons respectively, showing that different methods should be used for different weather conditions on estimating solar radiation with meteorological elements.

  13. Development of gridded solar radiation data over Belgium based on Meteosat and in-situ observations

    Science.gov (United States)

    Journée, Michel; Vanderveken, Gilles; Bertrand, Cédric

    2013-04-01

    Knowledge on solar resources is highly important for all forms of solar energy applications. With the recent development in solar-based technologies national meteorological services are faced with increasing demands for high-quality and reliable site-time specific solar resource information. Traditionally, solar radiation is observed by means of networks of meteorological stations. Costs for installation and maintenance of such networks are very high and national networks comprise only few stations. Consequently the availability of ground-based solar radiation measurements has proven to be spatially and temporally inadequate for many applications. To overcome such a limitation, a major effort has been undertaken at the Royal Meteorological Institute of Belgium (RMI) to provide the solar energy industry, the electricity sector, governments, and renewable energy organizations and institutions with the most suitable and accurate information on the solar radiation resources at the Earth's surface over the Belgian territory. Only space-based observations can deliver a global coverage of the solar irradiation impinging on horizontal surface at the ground level. Because only geostationary data allow to capture the diurnal cycle of the solar irradiance at the Earth's surface, a method that combines information from Meteosat Second Generation satellites and ground-measurement has been implemented at RMI to generate high resolution solar products over Belgium on an operational basis. Besides these new products, the annual and seasonal variability of solar energy resource was evaluated, solar radiation climate zones were defined and the recent trend in solar radiation was characterized.

  14. Human projected area factors for detailed direct and diffuse solar radiation analysis

    DEFF Research Database (Denmark)

    Kubaha, K.; Fiala, D.; Toftum, Jørn

    2004-01-01

    Projected area factors for individual segments of the standing and sedentary human body were modelled for both direct and diffuse solar radiation using detailed 3D geometry and radiation models. The local projected area factors with respect to direct short-wave radiation are a function of the solar...

  15. Application of solar radiation for heating and preparation of warm water in an individual house

    International Nuclear Information System (INIS)

    Kozak, Tadeeusz; Majchrzycka, Anna

    2009-01-01

    The paper is aimed at analysis of application of the solar collectors array for preparing of warm water and space heating in an individual house. Keywords: application of solar radiation, preparation of warm water, heating

  16. Medium level of direct solar radiation and energetic potential of solar concentrator in Minas Gerais State, Brazil; Niveis medios de radiacao solar direta e potencial energetico dos concentradores solares em Minas Gerais

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-07-01

    Basic concepts of solar energy, technical description of solar concentrators, its orientation and methodology of direct solar radiation measurement are discussed. An comparison of different solar radiation measurements methods, its methodology and its calculation steps are reported. Calculus and tables of the electric and thermal energy generation potential, through solar concentrators, on the state of Minas Gerais are also presented. 18 figs., 90 tabs., 12 refs.

  17. Five years of solar UV-radiation monitoring in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Josefsson, Weine

    1996-10-01

    A network of five stations measuring the solar UV-radiation has been operated for about five years. Data are presented as plotted time-series of monthly and yearly values for the sites. A general climatology can be deduced from these data. Daily and hourly maximum values are shown for each month as indicators of the potential extreme exposure levels. The large annual variation at high latitudes is easily seen in the data set. This illustrates the importance of the solar elevation on the level of the UV-irradiance. Influence of cloud variation and of larger changes in ozone is also detectable. A few examples of the daily variation also show the strong solar elevation dependence of the UV-irradiance. The quantity and unit of the UV-radiation in this presentation is CIE-weighted irradiance expressed as MED (minimum erythermal dose), where one MED equals 210 Jm{sup -2}. The values have been recomputed to refer to the international intercomparison of broad-band meters in Helsinki in 1995. In the following named WMO-STUK 1995 scale. As will be seen there are many sources of error and detailed studies are prevented by the large uncertainty connected with these data. Due to the short period of the record and the low accuracy no attempt to study trends is done. 6 refs, 27 figs, 4 tabs

  18. Models in the estimate of the diffuse solar radiation; Modelos de estimativa da radiacao solar difusa

    Energy Technology Data Exchange (ETDEWEB)

    Recieri, Reinaldo Prandini; Ferruzzi, Yuri; Silva, Suedemio de Lima [Universidade Estadual do Oeste do Parana (UNIOESTE/FAG), Cascavel, PR (Brazil). Curso de Mestrado em Engenharia Agricola; Quallio, Silvana [Universidade Estadual do Oeste do Parana (UNIOESTE/FAG), Cascavel, PR (Brazil). Curso de Biologia; Batista, Vitor Roberto Lourenco [Universidade Estadual do Oeste do Parana (UNIOESTE/FAG), Cascavel, PR (Brazil). Curso de Graduacao em Engenharia Eletrica

    2004-07-01

    In this work we evaluate, by means of polynomial regression analysis, several models that relate the diffuse fraction of the global radiation (K{sub d}) with the clearness index (K{sub t}). The experiment was conducted in the Solar Radiometry Station of Cascavel/PR from the first of January to the 31st of December, in the year of 2001. The solar radiation components were monitored by the following manufactured instruments: pyranometer (KIPP and ZONEN CM3) and pirheliometer (EPPLEY NIP) connected in a sun tracker (ST-1 model). A datalogger CR10X from the CAMPBELL SCIENTIFIC was used in the data acquisition. This datalogger was programmed in the frequency of 1 Hz storing an average of 5 minutes of collected data. Among the equations the best values of RMSE an MBE were find in the fourth and third degrees, respectively. We also find that the fourth degree polynomial equation (K{sub d}=1,172-1,001K{sub t}+3,992K{sub t}{sup 2}-11,742K{sub t}{sup 3}+7,698K{sub t}{sup 4}) generalizes the utilization of equations for diffuse solar radiation estimation. This means that this equation probably can be applied for any place and climatic conditions. (author)

  19. Studies of the Solar Radiations' Influence About Geomembranes Used in Ecological Landfill

    Science.gov (United States)

    Vasiluta, Petre; Cofaru, Ileana Ioana; Cofaru, Nicolae Florin; Popa, Dragos Laurentiu

    2017-12-01

    The study shown in this paper presents the behavior of geomembranes used at the ecological landfills. The influences of the solar radiations has a great importance regarding the correct mounting of the geomembranes. The mathematical model developed for the determination anytime and anywhere in the world for the next values and parameters: apparent solar time, solar declination, solar altitude, solar azimuth and incidence angle, zone angle, angle of sun elevation, solar declination, solar constant, solar flux density, diffuse solar radiation, global radiation, soil albedo, total radiant flux density and relational links of these values. The results of this model was used for creations an AutoCAD subroutines useful for choosing the correct time for correct mounting anywhere of the geomembranes

  20. General characterisation of the solar radiation behaviour in Mozambique

    Energy Technology Data Exchange (ETDEWEB)

    Cuamba, B.C. [Renewable Energies Research and Training Programme, Department of Physics, Faculty of Sciences, Eduardo Mondlane University (UEM), Maputo (Mozambique)]|[Action Group for Renewable Energies and Sustainable Development, Maputo (Mozambique); Chenene, M.L.; Mahumane, G. [Renewable Energies Research and Training Programme, Department of Physics, Faculty of Sciences, Eduardo Mondlane University (UEM), Maputo (Mozambique); Quissico, D.Z. [Renewable Energies Research and Training Programme, Department of Physics, Faculty of Sciences, Eduardo Mondlane University (UEM), Maputo (Mozambique)]|[National Institute of Meteorology, Maputo (Mozambique); Vasco, E. [National Institute of Meteorology, Maputo (Mozambique); Lovseth, J. [Solar Energy and Environmental Group, Department of Physics (LADE), Trondheim University of Science and Technology (NTNU) (Norway); O' Keefe, P. [University of Northumbria at Newcastle, Newcastle Upon Tyne (United Kingdom)

    2004-07-01

    Just as with the other Southern African Development Community (SADC) countries, Mozambique faces severe and interrelated problems of energy and environment linked with the massive consumption of fuel wood biomass. The conventional power grid caters for less than 7% of the energy needs for the country's 17 million inhabitants, and about 83% of the energy consumed in the country comes from biomass. Areas around the major urban centres and along the main development corridors are the most affected by energy shortages. This hinders the country's economic and social development as it is generally acknowledged that no development can be sustainable without linking it to energy planning and environmental management. Renewable energy resources can play an important role in the process of development of the country. From the vast renewable energy resources available in the country, solar energy represents one of those with the highest potential. Thus the evaluation of its potential is of extreme importance. This paper represents a first attempt to systemise the solar radiation data being measured by the National Institute of Meteorology (INAM). The period considered for analysis is from 1970 to 2000. Results of the present work reveal that the country has substantial solar energy resources for a variety of solar energy technologies. (orig.)

  1. Effects of increased solar ultraviolet radiation on biogeochemical cycles

    International Nuclear Information System (INIS)

    Zepp, R.G.; Callaghan, T.V.; Erickson, D.J.

    1995-01-01

    Increases in solar UV radiation could affect terrestrial and aquatic biogeochemical cycles thus altering both sources and sinks of greenhouse and chemically important trace gases (e.g., carbon dioxide (CO2), carbon monoxide (CO), carbonyl sulfide (COS). In terrestrial ecosystems, increased UV-B could modify both the production and decomposition of plant matter with concomitant changes in the uptake and release of atmospherically important trace gases. Decomposition processes can be accelerated when UV-B photodegrades surface litter, or retarded when the dominant effect involves changes in the chemical composition of living tissues that reduce the biodegradability of buried litter. These changes in decomposition can affect microbial production of CO2 and other trace gases and also may affect the availability of nutrients essential for plant growth. Primary production can be reduced by enhanced UV-B, but the effect is variable between species and even cultivars of some crops. Likewise, the effects of enhanced UV-B on photoproduction of CO from plant matter is species-dependent and occurs more efficiently from dead than from living matter. Aquatic ecosystems studies in several different locations have shown that reductions in current levels of solar UV-B result in enhanced primary production, and Antarctic experiments under the ozone hole demonstrated that primary production is inhibited by enhanced UV-B. In addition to its effects on primary production, solar UV radiation can reduce bacterioplankton growth in the upper ocean with potentially important effects on marine biogeochemical cycles. Decomposition processes can be retarded when bacterial activity is suppressed by enhanced UV-B radiation or stimulated when solar UV radiation photodegrades aquatic dissolved organic matter. Photodegradation of DOM results in loss of UV absorption and formation of dissolved inorganic carbon, CO, and organic substrates that are readily mineralized or taken up by aquatic

  2. A Proposal for a Thesaurus for Web Services in Solar Radiation

    Science.gov (United States)

    Gschwind, Benoit; Menard, Lionel; Ranchin, Thierry; Wald, Lucien; Stackhouse, Paul W., Jr.

    2007-01-01

    Metadata are necessary to discover, describe and exchange any type of information, resource and service at a large scale. A significant amount of effort has been made in the field of geography and environment to establish standards. Efforts still remain to address more specific domains such as renewable energies. This communication focuses on solar energy and more specifically on aspects in solar radiation that relate to geography and meteorology. A thesaurus in solar radiation is proposed for the keys elements in solar radiation namely time, space and radiation types. The importance of time-series in solar radiation is outlined and attributes of the key elements are discussed. An XML schema for encoding metadata is proposed. The exploitation of such a schema in web services is discussed. This proposal is a first attempt at establishing a thesaurus for describing data and applications in solar radiation.

  3. Interanual variability os solar radiation in Peninsula Iberica; Variabilidad interanual de la radiacion solar en la Peninsula Iberica

    Energy Technology Data Exchange (ETDEWEB)

    Pozo-Vazquez, D.; Tovar-Pescador, J.; Gamiz-Fortis, S.; Esteban-Parra, M.; Castro-Diez, Y.

    2004-07-01

    The NAO climatic phenomenon is the main responsible for the interanual cloud cover variability in Europe. We explore the relationship between the NAO and the solar radiation spatio-temporal variability in Europe during winter. Measured monthly sums of sunshine duration and short-wave downward solar flux reanalysis data have been used. Correlation analysis between the NAO index and the measured sunshine duration shows a maximum positive value (+0.75) over the Iberian Peninsula. Accordingly, solar radiation in this area undergoes an interanual variability that can reach up to 30%, with the derived consequences for a reliable solar energy resources evaluation. (Author)

  4. Solar Extreme UV radiation and quark nugget dark matter model

    Science.gov (United States)

    Zhitnitsky, Ariel

    2017-10-01

    We advocate the idea that the surprising emission of extreme ultra violet (EUV) radiation and soft x-rays from the Sun are powered externally by incident dark matter (DM) particles. The energy and the spectral shape of this otherwise unexpected solar irradiation is estimated within the quark nugget dark matter model. This model was originally invented as a natural explanation of the observed ratio Ωdark ~ Ωvisible when the DM and visible matter densities assume the same order of magnitude values. This generic consequence of the model is a result of the common origin of both types of matter which are formed during the same QCD transition and both proportional to the same fundamental dimensional parameter ΛQCD. We also present arguments suggesting that the transient brightening-like "nanoflares" in the Sun may be related to the annihilation events which inevitably occur in the solar atmosphere within this dark matter scenario.

  5. Rancang Bangun Solar Tracker Berbasis Mikrokontroler Atmega8535 Dengan Sensor Ldr Dan Penampil Lcd

    OpenAIRE

    Syafrialdi, Roni; -, Wildian

    2015-01-01

    This research aims to design a solar tracker using a four-quadrant LDR that used for sensing the position of the sun. Solar tracker is the tools used to follow the direction of motion of the sun. The electronic circuits consisting of a power supply circuit, microcontroller ATmega8535 and LCD circuit, stepper motor driver circuit and LDR sensor circuit. The mechanical design using dual axis with stepper motor as an actuator to position the solar cell tilted appropriately to face the sun direct...

  6. Effect of solar radiation and predacious microorganisms on survival of fecal and other bacteria.

    OpenAIRE

    McCambridge, J; McMeekin, T A

    1981-01-01

    The effect of solar radiation and predacious microorganisms on the survival of bacteria of fecal and plant origin was studied. The decline in the numbers of Escherichia coli cells in estuarine water samples was found to be significantly greater in the presence of both naturally occurring microbial predators and solar radiation than when each of these factors was acting independently. The effect of solar radiation on microbial predators was negligible, whereas the susceptibility of bacteria to...

  7. The relationship between incoming solar radiation and daily air temperature

    International Nuclear Information System (INIS)

    Kpeglo, Daniel Kwasi

    2013-07-01

    Solar radiation is the ultimate source of energy for the planet. To predict the values of temperature and instant solar radiation when equipment are not readily available from obtained equations, a good knowledge and understanding of the disposition and distribution of solar radiation is a requirement for modelling earth’s weather and climate change variables. A pyranometer (CM3) in series with a PHYWE amplifier and a voltmeter were experimentally set-up and used to study the amount of solar radiation received at the Physics Department of the University of Ghana during the day. The temperature of the study area as well as the Relative Humidity was also recorded. Data was collected over a period of one month (from 2nd to 24th April, 2012). Days for which rain was recorded were ignored because rain could damage the pyranometer. The data obtained by the set-up were therefore used to compare with data obtained by a wireless weather station (Davis Vintage Pro). The data from these separate set-ups indicated that a perfect correlation existed between the solar radiation and temperature of the place. The data obtained by the experimental set-up was split into two separate sessions as morning and evening sessions. It was observed that the experimental set-up had a good correlation with that of the weather station on a particular day 11th April, 2012. The various Regression Coefficient (R"2) values for morning session were respectively R"2 = 0.96 and R"2 = 0.95 with their respective equations as I_W =136.22T_W - 40623 and I_p = 2.3198T_p - 678.14. The evening session also had good Regression Coefficient values of R"2 = 0.81 and R"2 = 0.97 with equations of 2.1098T_p - 625 and I_W = 161.31T_w - 4876.9. Similar analysis of the data from the separate set-ups gave a better correlation for that of the experimental set-up than that of the wireless station. The range of values of Regression Coefficient (R"2) for the experimental set-up was between 0.82 − 0.99 for the morning

  8. Fluid dynamic analysis and experimental study of a low radiation error temperature sensor

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jie, E-mail: yangjie396768@163.com [Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing 210044 (China); School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing 210044 (China); Liu, Qingquan, E-mail: andyucd@163.com [Jiangsu Key Laboratory of Meteorological Observation and Information Processing, Nanjing 210044 (China); Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology, Nanjing 210044 (China); Dai, Wei, E-mail: daiweiilove@163.com [Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing 210044 (China); School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing 210044 (China); Ding, Renhui, E-mail: drhabcd@sina.com [Jiangsu Meteorological Observation Center, Nanjing 210008 (China)

    2017-01-30

    To improve the air temperature observation accuracy, a low radiation error temperature sensor is proposed. A Computational Fluid Dynamics (CFD) method is implemented to obtain radiation errors under various environmental conditions. The low radiation error temperature sensor, a naturally ventilated radiation shield, a thermometer screen and an aspirated temperature measurement platform are characterized in the same environment to conduct the intercomparison. The aspirated platform served as an air temperature reference. The mean radiation errors of the naturally ventilated radiation shield and the thermometer screen are 0.57 °C and 0.32 °C, respectively. In contrast, the mean radiation error of the low radiation error temperature sensor is 0.05 °C. The low radiation error temperature sensor proposed in this research may be helpful to provide a relatively accurate air temperature measurement result. - Highlights: • A CFD method is applied to obtain a quantitative solution of radiation error. • A temperature sensor is proposed to minimize radiation error. • The radiation error of the temperature sensor is on the order of 0.05 °C.

  9. The Energy Under Our Feet: A Study of Solar Radiation

    Science.gov (United States)

    Weiss, I.

    2016-12-01

    In this experiment I tested if asphalt pavement can produce enough solar heat to produce energy through a system that uses water, solar energy and heat. A setup that can conserve the water and prevent it from evaporating, as well as measuring the energy production is required to run this experiment. I have done a lot of research on this experiment and found that there are several variables that impact the results of this experiment. 1. The surface temperature compared to the air temperature 2. The Geographical location of the pavement 3. The time of the year 4. Cloud coverage for the day Overall there will be many variables I will have to keep out of the experiment such as temperature ranges, season changes and geographical location. My constant will be my location at 33.7086o North and 117.9564o West. Asphalt pavements do not reflect the sunlight and hence heat up faster than a light surface that would reflect the sunlight. This means the Asphalt absorbs the solar radiation, which increases the temperature of the air around the asphalt contributing to what is known as the urban heat island effect. This heating in turn contributes to the formation of smog and ozone products. With the population still growing this would also mean an increase in this temperature and hence an increase in smog and ozone, creating a significant health concern. Cities need to start looking at ways to cool their pavement and find ways to harvest the energy created by their streets. Installing pipes with water can provide that solution and not only reduce the heat reflected from the pavement but also harvest energy from this setup, and decrease the smog production and maintain a balance in ozone levels. As well as the asphalt needed to run the testing, a Stirling engine is required. A Stirling Engine is a highly efficient engine that can run on a variety of heat sources. Because it is highly compatible with alternative energy and renewable energy sources it could become increasingly

  10. Open-WiSe: A Solar Powered Wireless Sensor Network Platform

    Science.gov (United States)

    González, Apolinar; Aquino, Raúl; Mata, Walter; Ochoa, Alberto; Saldaña, Pedro; Edwards, Arthur

    2012-01-01

    Because battery-powered nodes are required in wireless sensor networks and energy consumption represents an important design consideration, alternate energy sources are needed to provide more effective and optimal function. The main goal of this work is to present an energy harvesting wireless sensor network platform, the Open Wireless Sensor node (WiSe). The design and implementation of the solar powered wireless platform is described including the hardware architecture, firmware, and a POSIX Real-Time Kernel. A sleep and wake up strategy was implemented to prolong the lifetime of the wireless sensor network. This platform was developed as a tool for researchers investigating Wireless sensor network or system integrators. PMID:22969396

  11. Solar Probe Plus MAG Sensor Thermal Design for Low Heater Power and Extreme Thermal Environment

    Science.gov (United States)

    Choi, Michael K.

    2015-01-01

    The heater power available for the Solar Probe Plus FIELDS MAG sensor is less than half of the heritage value for other missions. Nominally the MAG sensors are in the spacecraft's umbra. In the worst hot case, approximately 200 spacecraft communication downlinks, up to 10 hours each, are required at 0.7 AU. These downlinks require the spacecraft to slew 45 deg. about the Y-axis, exposing the MAG sensors and boom to sunlight. This paper presents the thermal design to meet the MAG sensor thermal requirements in the extreme thermal environment and with low heater power. A thermal balance test on the MAG sensor engineering model has verified the thermal design and correlated the thermal model for flight temperature predictions.

  12. Powering Autonomous Sensors An Integral Approach with Focus on Solar and RF Energy Harvesting

    CERN Document Server

    Penella-López, María Teresa

    2011-01-01

    Autonomous sensors transmit data and power their electronics without using cables. They can be found in e.g. wireless sensor networks (WSNs) or remote acquisition systems. Although primary batteries provide a simple design for powering autonomous sensors, they present several limitations such as limited capacity and power density, and difficulty in predicting their condition and state of charge. An alternative is to extract energy from the ambient (energy harvesting). However, the reduced dimensions of most autonomous sensors lead to a low level of available power from the energy transducer. Thus, efficient methods and circuits to manage and gather the energy are a must. An integral approach for powering autonomous sensors by considering both primary batteries and energy harvesters is presented. Two rather different forms of energy harvesting are also dealt with: optical (or solar) and radiofrequency (RF). Optical energy provides high energy density, especially outdoors, whereas RF remote powering is possibly...

  13. Open-WiSe: A Solar Powered Wireless Sensor Network Platform

    Directory of Open Access Journals (Sweden)

    Arthur Edwards

    2012-06-01

    Full Text Available Because battery-powered nodes are required in wireless sensor networks and energy consumption represents an important design consideration, alternate energy sources are needed to provide more effective and optimal function. The main goal of this work is to present an energy harvesting wireless sensor network platform, the Open Wireless Sensor node (WiSe. The design and implementation of the solar powered wireless platform is described including the hardware architecture, firmware, and a POSIX Real-Time Kernel. A sleep and wake up strategy was implemented to prolong the lifetime of the wireless sensor network. This platform was developed as a tool for researchers investigating Wireless sensor network or system integrators.

  14. Modeling Radiation Damage to Pixel Sensors in the ATLAS Detector

    CERN Document Server

    Ducourthial, Audrey; The ATLAS collaboration

    2017-01-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC), the innermost layers will receive a fluence in excess of $10^{15} n_{eq}/cm^2$ and the HL-HLC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects to the ATLAS pixel sensors for the first time. In addition to thoroughly describing the setup, we present first predictions for basic pixel cluster properties alongside...

  15. Modeling radiation damage to pixel sensors in the ATLAS detector

    CERN Document Server

    Ducourthial, Audrey; The ATLAS collaboration

    2017-01-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC). As the closest detector component to the interaction point, these detectors will be subjected to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC), the innermost layers will receive a fluence in excess of $10^{15}n_{eq}/cm^2$ and the HL-HLC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is critical in order to make accurate predictions for current future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects to the ATLAS pixel sensors for the first time. In addition to thoroughly describing the setup, we present first predictions for basic pixel cluster properties alongside ...

  16. Modeling radiation damage to pixel sensors in the ATLAS detector

    Science.gov (United States)

    Ducourthial, A.

    2018-03-01

    Silicon pixel detectors are at the core of the current and planned upgrade of the ATLAS detector at the Large Hadron Collider (LHC) . As the closest detector component to the interaction point, these detectors will be subject to a significant amount of radiation over their lifetime: prior to the High-Luminosity LHC (HL-LHC) [1], the innermost layers will receive a fluence in excess of 1015 neq/cm2 and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. Simulating radiation damage is essential in order to make accurate predictions for current and future detector performance that will enable searches for new particles and forces as well as precision measurements of Standard Model particles such as the Higgs boson. We present a digitization model that includes radiation damage effects on the ATLAS pixel sensors for the first time. In addition to thoroughly describing the setup, we present first predictions for basic pixel cluster properties alongside early studies with LHC Run 2 proton-proton collision data.

  17. Synergistic effect of solar radiation and solar heating to disinfect drinking water sources.

    Science.gov (United States)

    Rijal, G K; Fujioka, R S

    2001-01-01

    Waterborne diseases are still common in developing countries as drinking water sources are contaminated and feasible means to reliably treat and disinfect these waters are not available. Many of these developing countries are in the tropical regions of the world where sunlight is plentiful. The objective of this study was to evaluate the effectiveness of combining solar radiation and solar heating to disinfect contaminated water using a modified Family Sol*Saver System (FSP). The non-UV transmittable cover sheet of the former FSP system was replaced with an UV transmittable plastic cover sheet to enable more wavelengths of sunlight to treat the water. Disinfection efficiency of both systems was evaluated based on reduction of the natural populations of faecal coliform, E. coli, enterococci, C. perfringens, total heterotrophic bacteria, hydrogen sulphide producing bacteria and FRNA virus. The results showed that under sunny and partly sunny conditions, water was heated to critical temperature (60 degrees C) in both the FSP systems inactivating more than 3 log (99.9%) of the concentrations of faecal coliform and E. coli to undetectable levels of heat worked synergistically to enhance the inactivation of faecal indicator bacteria. The relative log removal of indicator microorganism in the FSP treated water was total heterotrophic bacteria heat and radiation effects of sunlight were important in disinfecting water by solar units. The data indicated that direct radiation of sunlight worked synergistically with solar heating of the water to disinfect the water. Thus, effective disinfection was observed even when the water temperature did not reach 60 degrees C. Finally, the hydrogen sulphide test is a simple and reliable test that householders can use to determine whether their water had been sufficiently disinfected.

  18. Determination of incoming solar radiation in major tree species in Turkey.

    Science.gov (United States)

    Yilmaz, Osman Yalcin; Sevgi, Orhan; Koc, Ayhan

    2012-07-01

    Light requirements and spatial distribution of major forest tree species in Turkey hasn't been analyzed yet. Continuous surface solar radiation data, especially at mountainous-forested areas, are needed to put forward this relationship between forest tree species and solar radiation. To achieve this, GIS-based modeling of solar radiation is one of the methods used in rangelands to estimate continuous surface solar radiation. Therefore, mean monthly and annual total global solar radiation maps of whole Turkey were computed spatially using GRASS GIS software "r.sun" model under clear-sky (cloudless) conditions. 147498 pure forest stand point-based data were used in the study for calculating mean global solar radiation values of all the major forest tree species of Turkey. Beech had the lowest annual mean total global solar radiation value of 1654.87 kWh m(-2), whereas juniper had the highest value of 1928.89 kWh m(-2). The rank order of tree species according to the mean monthly and annual total global solar radiation values, using a confidence level of p solar radiation values of sites and light requirements of forest trees ranked similarly.

  19. Mathematical Modeling and Numerical Analysis of Thermal Distribution in Arch Dams considering Solar Radiation Effect

    Science.gov (United States)

    Mirzabozorg, H.; Hariri-Ardebili, M. A.; Shirkhan, M.; Seyed-Kolbadi, S. M.

    2014-01-01

    The effect of solar radiation on thermal distribution in thin high arch dams is investigated. The differential equation governing thermal behavior of mass concrete in three-dimensional space is solved applying appropriate boundary conditions. Solar radiation is implemented considering the dam face direction relative to the sun, the slop relative to horizon, the region cloud cover, and the surrounding topography. It has been observed that solar radiation changes the surface temperature drastically and leads to nonuniform temperature distribution. Solar radiation effects should be considered in thermal transient analysis of thin arch dams. PMID:24695817

  20. Performance of Sayigh's universal formula in the estimation of global solar radiation in Ghana

    International Nuclear Information System (INIS)

    Oduro Afriyie, K.

    1995-10-01

    The performance of Sayigh's universal formula for the estimation of global solar radiation is tested against that of Angstrom-Black model for 13 stations in Ghana, using monthly mean daily global solar radiation averaged over the years 1957-1981. Sayigh's model is found not to perform as credibility as the Angstrom-Black model in the estimation of monthly global solar radiation in Ghana. Of the 156 values of monthly global solar radiation estimated by Sayigh's model, 123 (or 78.8%) had discrepancies of more than 10% with the measured values. The corresponding value for the Angstrom-Black model was 7 (or 4.5%). (author). 5 refs

  1. Mathematical modeling and numerical analysis of thermal distribution in arch dams considering solar radiation effect.

    Science.gov (United States)

    Mirzabozorg, H; Hariri-Ardebili, M A; Shirkhan, M; Seyed-Kolbadi, S M

    2014-01-01

    The effect of solar radiation on thermal distribution in thin high arch dams is investigated. The differential equation governing thermal behavior of mass concrete in three-dimensional space is solved applying appropriate boundary conditions. Solar radiation is implemented considering the dam face direction relative to the sun, the slop relative to horizon, the region cloud cover, and the surrounding topography. It has been observed that solar radiation changes the surface temperature drastically and leads to nonuniform temperature distribution. Solar radiation effects should be considered in thermal transient analysis of thin arch dams.

  2. A possible radiation-resistant solar cell geometry using superlattices

    Science.gov (United States)

    Goradia, C.; Clark, R.; Brinker, D.

    1985-01-01

    A solar cell structure is proposed which uses a GaAs nipi doping superlattice. An important feature of this structure is that photogenerated minority carriers are very quickly collected in a time shorter than bulk lifetime in the fairly heavily doped n and p layers and these carriers are then transported parallel to the superlattice layers to selective ohmic contacts. Assuming that these already-separated carriers have very long recombination lifetimes, due to their across an indirect bandgap in real space, it is argued that the proposed structure may exhibit superior radiation tolerance along with reasonably high beginning-of-life efficiency.

  3. Global Performance of a Fast Parameterization Scheme for Estimating Surface Solar Radiation from MODIS data

    Science.gov (United States)

    Tang, W.; Yang, K.; Sun, Z.; Qin, J.; Niu, X.

    2016-12-01

    A fast parameterization scheme named SUNFLUX is used in this study to estimate instantaneous surface solar radiation (SSR) based on products from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor onboard both Terra and Aqua platforms. The scheme mainly takes into account the absorption and scattering processes due to clouds, aerosols and gas in the atmosphere. The estimated instantaneous SSR is evaluated against surface observations obtained from seven stations of the Surface Radiation Budget Network (SURFRAD), four stations in the North China Plain (NCP) and 40 stations of the Baseline Surface Radiation Network (BSRN). The statistical results for evaluation against these three datasets show that the relative root-mean-square error (RMSE) values of SUNFLUX are less than 15%, 16% and 17%, respectively. Daily SSR is derived through temporal upscaling from the MODIS-based instantaneous SSR estimates, and is validated against surface observations. The relative RMSE values for daily SSR estimates are about 16% at the seven SURFRAD stations, four NCP stations, 40 BSRN stations and 90 China Meteorological Administration (CMA) radiation stations.

  4. Evaluation of different models to estimate the global solar radiation on inclined surface

    Science.gov (United States)

    Demain, C.; Journée, M.; Bertrand, C.

    2012-04-01

    Global and diffuse solar radiation intensities are, in general, measured on horizontal surfaces, whereas stationary solar conversion systems (both flat plate solar collector and solar photovoltaic) are mounted on inclined surface to maximize the amount of solar radiation incident on the collector surface. Consequently, the solar radiation incident measured on a tilted surface has to be determined by converting solar radiation from horizontal surface to tilted surface of interest. This study evaluates the performance of 14 models transposing 10 minutes, hourly and daily diffuse solar irradiation from horizontal to inclined surface. Solar radiation data from 8 months (April to November 2011) which include diverse atmospheric conditions and solar altitudes, measured on the roof of the radiation tower of the Royal Meteorological Institute of Belgium in Uccle (Longitude 4.35°, Latitude 50.79°) were used for validation purposes. The individual model performance is assessed by an inter-comparison between the calculated and measured solar global radiation on the south-oriented surface tilted at 50.79° using statistical methods. The relative performance of the different models under different sky conditions has been studied. Comparison of the statistical errors between the different radiation models in function of the clearness index shows that some models perform better under one type of sky condition. Putting together different models acting under different sky conditions can lead to a diminution of the statistical error between global measured solar radiation and global estimated solar radiation. As models described in this paper have been developed for hourly data inputs, statistical error indexes are minimum for hourly data and increase for 10 minutes and one day frequency data.

  5. Estimating solar radiation using NOAA/AVHRR and ground measurement data

    Science.gov (United States)

    Fallahi, Somayeh; Amanollahi, Jamil; Tzanis, Chris G.; Ramli, Mohammad Firuz

    2018-01-01

    Solar radiation (SR) data are commonly used in different areas of renewable energy research. Researchers are often compelled to predict SR at ground stations for areas with no proper equipment. The objective of this study was to test the accuracy of the artificial neural network (ANN) and multiple linear regression (MLR) models for estimating monthly average SR over Kurdistan Province, Iran. Input data of the models were two data series with similar longitude, latitude, altitude, and month (number of months) data, but there were differences between the monthly mean temperatures in the first data series obtained from AVHRR sensor of NOAA satellite (DS1) and in the second data series measured at ground stations (DS2). In order to retrieve land surface temperature (LST) from AVHRR sensor, emissivity of the area was considered and for that purpose normalized vegetation difference index (NDVI) calculated from channels 1 and 2 of AVHRR sensor was utilized. The acquired results showed that the ANN model with DS1 data input with R2 = 0.96, RMSE = 1.04, MAE = 1.1 in the training phase and R2 = 0.96, RMSE = 1.06, MAE = 1.15 in the testing phase achieved more satisfactory performance compared with MLR model. It can be concluded that ANN model with remote sensing data has the potential to predict SR in locations with no ground measurement stations.

  6. UD-WCMA: An Energy Estimation and Forecast Scheme for Solar Powered Wireless Sensor Networks

    KAUST Repository

    Dehwah, Ahmad H.; Elmetennani, Shahrazed; Claudel, Christian

    2017-01-01

    -WCMA) to estimate and predict the variations of the solar power in a wireless sensor network. The presented approach combines the information from the real-time measurement data and a set of stored profiles representing the energy patterns in the WSNs location

  7. Radiation effects in silicon and gallium arsenide solar cells using isotropic and normally incident radiation

    Science.gov (United States)

    Anspaugh, B. E.; Downing, R. G.

    1984-01-01

    Several types of silicon and gallium arsenide solar cells were irradiated with protons with energies between 50 keV and 10 MeV at both normal and isotropic incidence. Damage coefficients for maximum power relative to 10 MeV were derived for these cells for both cases of omni-directional and normal incidence. The damage coefficients for the silicon cells were found to be somewhat lower than those quoted in the Solar Cell Radiation Handbook. These values were used to compute omni-directional damage coefficients suitable for solar cells protected by coverglasses of practical thickness, which in turn were used to compute solar cell degradation in two proton-dominated orbits. In spite of the difference in the low energy proton damage coefficients, the difference between the handbook prediction and the prediction using the newly derived values was negligible. Damage coefficients for GaAs solar cells for short circuit current, open circuit voltage, and maximum power were also computed relative to 10 MeV protons. They were used to predict cell degradation in the same two orbits and in a 5600 nmi orbit. Results show the performance of the GaAs solar cells in these orbits to be superior to that of the Si cells.

  8. Share of erythema dose of solar radiation in high mountains

    International Nuclear Information System (INIS)

    Blumthaler, M.; Ambach, W.

    1987-01-01

    The erythema dose was measured using a Robertson-Berger Sunburn Meter. The spectral sensitivity of the detector is adapted to an erythema action spectrum with the optical center at about 300 nm. The erythema dose is expressed in the biologically relevant Sunburn Units (SU). The Robertson-Berger Sunburn Meter has been recommended by the WMO for global monitoring of solar UV-B erythema dose. UV-A radiation was measured with a UV-radiometer. The spectral sensitivity of the detector has a flat maximum at 345 nm and a half band width of +- 25 nm. Global radiation was measured using a pyranometer. All detectors were placed horizontally and calibrated several times. Readings were taken in intervals of one minute

  9. Radiation resistance of amorphous silicon alloy solar cells

    International Nuclear Information System (INIS)

    Hanak, J.J.; Chen, E.; Myatt, A.; Woodyard, J.R.

    1987-01-01

    The radiation resistance of a-Si alloy solar cells when bombarded by high energy particles is reviewed. The results of investigations of high energy proton radiation resistance of a-Si alloy thin film photovoltaic cells are reported. Irradiations were carried out with 200 keV and 1.00 MeV protons with fluences ranging betweeen 1E11 and 1E15 cm-2. Defect generation and passivation mechanisms were studied using the AM1 conversion efficiency and isochronal anneals. It is concluded that the primary defect generation mechanism results from the knock-on of Si and Ge in the intrinsic layer of the cells. The defect passivation proceeds by the complex annealing of Si and Ge defects and not by the simple migration of hydrogen

  10. Impact of Solar Radiation on Gene Expression in Bacteria

    Directory of Open Access Journals (Sweden)

    Sabine Matallana-Surget

    2013-07-01

    Full Text Available Microorganisms often regulate their gene expression at the level of transcription and/or translation in response to solar radiation. In this review, we present the use of both transcriptomics and proteomics to advance knowledge in the field of bacterial response to damaging radiation. Those studies pertain to diverse application areas such as fundamental microbiology, water treatment, microbial ecology and astrobiology. Even though it has been demonstrated that mRNA abundance is not always consistent with the protein regulation, we present here an exhaustive review on how bacteria regulate their gene expression at both transcription and translation levels to enable biomarkers identification and comparison of gene regulation from one bacterial species to another.

  11. Multi-dimensional fiber-optic radiation sensor for ocular proton therapy dosimetry

    International Nuclear Information System (INIS)

    Jang, K.W.; Yoo, W.J.; Moon, J.; Han, K.T.; Park, B.G.; Shin, D.; Park, S-Y.; Lee, B.

    2012-01-01

    In this study, we fabricated a multi-dimensional fiber-optic radiation sensor, which consists of organic scintillators, plastic optical fibers and a water phantom with a polymethyl methacrylate structure for the ocular proton therapy dosimetry. For the purpose of sensor characterization, we measured the spread out Bragg-peak of 120 MeV proton beam using a one-dimensional sensor array, which has 30 fiber-optic radiation sensors with a 1.5 mm interval. A uniform region of spread out Bragg-peak using the one-dimensional fiber-optic radiation sensor was obtained from 20 to 25 mm depth of a phantom. In addition, the Bragg-peak of 109 MeV proton beam was measured at the depth of 11.5 mm of a phantom using a two-dimensional sensor array, which has 10×3 sensor array with a 0.5 mm interval.

  12. Evaluating solar radiation on a tilted surfaces - a study case in Timis (Romania)

    International Nuclear Information System (INIS)

    Vasar, C; Prostean, O; Prostean, G

    2016-01-01

    In the last years the usage of solar energy has grown considerably in Romania, as well as in Europe, stimulated by various factors as government programs, green pricing policies, decreasing of photovoltaic components cost etc. Also, the rising demand of using Solar Energy Conversion Systems (SECS) is driven by the desire of individuals or companies to obtain energy from a clean renewable source. In many applications, remote consumers far from other energetic grids can use solar systems more cost-effectively than extending the grid to reach the location. Usually the solar energy is measured or forecast on horizontal surface, but in SECS there is needed the total solar radiation incident on the collector surface, that is oriented in a position that maximize the harvested energy. There are many models that convert the solar radiation from horizontal surface to a tilted surface, but they use empirical coefficients and the accuracy is influenced by different facts as geographical location or sky conditions. Such models were used considering measured values for solar radiation on horizontal plane, in the western part of Romania. Hourly values measured for global solar irradiation on the horizontal plane, diffuse solar irradiation on the horizontal plane and reflected solar irradiation by ground are used to compute the total solar radiation incident on different tilted surfaces. The calculated incident radiation is then compared with the real radiation measured on tilted surface in order to evaluate the performance of the considered conversion models. (paper)

  13. Solar radiation and cooling load calculation for radiant systems: Definition and evaluation of the Direct Solar Load

    DEFF Research Database (Denmark)

    Causone, Francesco; Corgnati, Stefano P.; Filippi, Marco

    2010-01-01

    The study of the influence of solar radiation on the built environment is a basic issue in building physics and currently it is extremely important because glazed envelopes are widely used in contemporary architecture. In the present study, the removal of solar heat gains by radiant cooling systems...... is investigated. Particular attention is given to the portion of solar radiation converted to cooling load, without taking part in thermal absorption phenomena due to the thermal mass of the room. This specific component of the cooling load is defined as the Direct Solar Load. A simplified procedure to correctly...... calculate the magnitude of the Direct Solar Load in cooling load calculations is proposed and it is implemented with the Heat Balance method and the Radiant Time Series method. The F ratio of the solar heat gains directly converted to cooling load, in the case of a low thermal mass radiant ceiling...

  14. Monitoring And Recording Data For Solar Radiation Temperature And Charging Current

    Directory of Open Access Journals (Sweden)

    Aung Bhone Myint

    2015-08-01

    Full Text Available A data logger based on 8051 microcontroller has been implemented in this project to measure the solar radiation temperature and charging current. Development of a low-cost data logger can easily be made and easily be used to convert the analog signal of physical parameters of various test or other purposes of engineering. By using a suitable program code it can be used to read the value digitally with a PC. Our aim is to provide with a module and a software package when installed in a computer one can remotely acquire and monitor several numbers of the same or different types of signals sequentially at a time. Signals obtained from various sensors have been effectively conditioned. Now interfacing these signals using ADC with the Bluetooth module port of a computer satisfies the very goal of data acquisition. Proposed system provides better performance and has low cost versatile portable.

  15. Effects of solar PAR and UV radiation on tropical biofouling communities

    KAUST Repository

    Dobretsov, SV; Gosselin, L; Qian, P

    2010-01-01

    We investigated the effect of solar ultraviolet radiation (UVR) and photosynthetically active radiation (PAR) on the development of tropical micro- and macrofouling communities for 30 d. The experimental design involved 3 treatments: full spectrum

  16. Estimation of daily global solar radiation as a function of the solar energy potential at soil surface

    International Nuclear Information System (INIS)

    Pereira, A.B.; Vrisman, A.L.; Galvani, E.

    2002-01-01

    The solar radiation received at the surface of the earth, apart from its relevance to several daily human activities, plays an important role in the growth and development of plants. The aim of the current work was to develop and gauge an estimation model for the evaluation of the global solar radiation flux density as a function of the solar energy potential at soil surface. Radiometric data were collected at Ponta Grossa, PR, Brazil (latitude 25°13' S, longitude 50°03' W, altitude 880 m). Estimated values of solar energy potential obtained as a function of only one measurement taken at solar noon time were confronted with those measured by a Robitzsch bimetalic actinograph, for days that presented insolation ratios higher than 0.85. This data set was submitted to a simple linear regression analysis, having been obtained a good adjustment between observed and calculated values. For the estimation of the coefficients a and b of Angström's equation, the method based on the solar energy potential at soil surface was used for the site under study. The methodology was efficient to assess the coefficients, aiming at the determination of the global solar radiation flux density, whith quickness and simplicity, having also found out that the criterium for the estimation of the solar energy potential is equivalent to that of the classical methodology of Angström. Knowledge of the available solar energy potential and global solar radiation flux density is of great importance for the estimation of the maximum atmospheric evaporative demand, of water consumption by irrigated crops, and also for building solar engineering equipment, such as driers, heaters, solar ovens, refrigerators, etc [pt

  17. Natural Antioxidants: Multiple Mechanisms to Protect Skin From Solar Radiation

    Directory of Open Access Journals (Sweden)

    Spencer Dunaway

    2018-04-01

    Full Text Available Human skin exposed to solar ultraviolet radiation (UVR results in a dramatic increase in the production of reactive oxygen species (ROS. The sudden increase in ROS shifts the natural balance toward a pro-oxidative state, resulting in oxidative stress. The detrimental effects of oxidative stress occur through multiple mechanisms that involve alterations to proteins and lipids, induction of inflammation, immunosuppression, DNA damage, and activation of signaling pathways that affect gene transcription, cell cycle, proliferation, and apoptosis. All of these alterations promote carcinogenesis and therefore, regulation of ROS levels is critical to the maintenance of normal skin homeostasis. Several botanical products have been found to exhibit potent antioxidant capacity and the ability to counteract UV-induced insults to the skin. These natural products exert their beneficial effects through multiple pathways, including some known to be negatively affected by solar UVR. Aging of the skin is also accelerated by UVR exposure, in particular UVA rays that penetrate deep into the epidermis and the dermis where it causes the degradation of collagen and elastin fibers via oxidative stress and activation of matrix metalloproteinases (MMPs. Because natural compounds are capable of attenuating some of the UV-induced aging effects in the skin, increased attention has been generated in the area of cosmetic sciences. The focus of this review is to cover the most prominent phytoproducts with potential to mitigate the deleterious effects of solar UVR and suitability for use in topical application.

  18. Effects of solar radiation on the orbits of small particles

    Science.gov (United States)

    Lyttleton, R. A.

    1976-01-01

    A modification of the Robertson (1937) equations of particle motion in the presence of solar radiation is developed which allows for partial reflection of sunlight as a result of rapid and varying particle rotations caused by interaction with the solar wind. The coefficients and forces in earlier forms of the equations are compared with those in the present equations, and secular rates of change of particle orbital elements are determined. Orbital dimensions are calculated in terms of time, probable sizes and densities of meteoric and cometary particles are estimated, and times of infall to the sun are computed for a particle moving in an almost circular orbit and a particle moving in an elliptical orbit of high eccentricity. Changes in orbital elements are also determined for particles from a long-period sun-grazing comet. The results show that the time of infall to the sun from a highly eccentric orbit is substantially shorter than from a circular orbit with a radius equal to the mean distance in the eccentric orbit. The possibility is considered that the free orbital kinetic energy of particles drawn into the sun may be the energy source for the solar corona.

  19. Long Term Solar Radiation Forecast Using Computational Intelligence Methods

    Directory of Open Access Journals (Sweden)

    João Paulo Coelho

    2014-01-01

    Full Text Available The point prediction quality is closely related to the model that explains the dynamic of the observed process. Sometimes the model can be obtained by simple algebraic equations but, in the majority of the physical systems, the relevant reality is too hard to model with simple ordinary differential or difference equations. This is the case of systems with nonlinear or nonstationary behaviour which require more complex models. The discrete time-series problem, obtained by sampling the solar radiation, can be framed in this type of situation. By observing the collected data it is possible to distinguish multiple regimes. Additionally, due to atmospheric disturbances such as clouds, the temporal structure between samples is complex and is best described by nonlinear models. This paper reports the solar radiation prediction by using hybrid model that combines support vector regression paradigm and Markov chains. The hybrid model performance is compared with the one obtained by using other methods like autoregressive (AR filters, Markov AR models, and artificial neural networks. The results obtained suggests an increasing prediction performance of the hybrid model regarding both the prediction error and dynamic behaviour.

  20. A solar radiation model for use in climate studies

    Science.gov (United States)

    Chou, Ming-Dah

    1992-01-01

    A solar radiation routine is developed for use in climate studies that includes absorption and scattering due to ozone, water vapor, oxygen, carbon dioxide, clouds, and aerosols. Rayleigh scattering is also included. Broadband parameterization is used to compute the absorption by water vapor in a clear atmosphere, and the k-distribution method is applied to compute fluxes in a scattering atmosphere. The reflectivity and transmissivity of a scattering layer are computed analytically using the delta-four-stream discrete-ordinate approximation. The two-stream adding method is then applied to compute fluxes for a composite of clear and scattering layers. Compared to the results of high spectral resolution and detailed multiple-scattering calculations, fluxes and heating rate are accurately computed to within a few percent. The high accuracy of the flux and heating-rate calculations is achieved with a reasonable amount of computing time. With the UV and visible region grouped into four bands, this solar radiation routine is useful not only for climate studies but also for studies on photolysis in the upper atmosphere and photosynthesis in the biosphere.

  1. Mechanism on radiation degradation of Si space solar cells

    International Nuclear Information System (INIS)

    Yamaguchi, Masafumi; Taylor, S.J.; Hisamatsu, Tadashi; Matsuda, Sumio

    1998-01-01

    Radiation testing of Si n + -p-p + structure space solar cells has revealed an anomalous increase in short-circuit current Isc, followed by an abrupt decrease and cell failure, induced by high fluence electron and proton irradiations. A model to explain these phenomena by expressing the change in carrier concentration p of the base region is proposed in addition to the well-known model where Isc is decreased by minority-carrier lifetime reduction with irradiation. Change in carrier concentration causes broadening the depletion layer to contribute increase in the generated photocurrent and increase in recombination-generation current in the depletion layer, and increase in the resistivity of the base layer to result in the abrupt decrease of Isc and failure of the solar cell. Type conversion from p-type to n-type in base layer has been confirmed by EBIC (electron-beam induced current) and spectral response measurements. Moreover, origins of radiation-induced defects in heavily irradiated Si and generation of deep donor defects have also been examined by using DLTS (deep level transient spectroscopy) analysis. (author)

  2. Concrete Hydration Heat Analysis for RCB Basemat Considering Solar Radiation

    International Nuclear Information System (INIS)

    Lee, Seong-Cheol; Son, Yong-Ki; Choi, Seong-Cheol

    2015-01-01

    The NPP especially puts an emphasis on concrete durability for structural integrity. It has led to higher cementitious material contents, lower water-cementitious-material ratios, and deeper cover depth over reinforcing steel. These requirements have resulted in more concrete placements that are subject to high internal temperatures. The problem with high internal temperatures is the increase in the potential for thermal cracking that can decrease concrete's long-term durability and ultimate strength. Thermal cracking negates the benefits of less permeable concrete and deeper cover by providing a direct path for corrosion-causing agents to reach the reinforcing steel. The purpose of this study is to develop how to analyze and estimate accurately concrete hydration heat of the real-scale massive concrete with wide large plane. An analysis method considering concrete placement sequence was studied and solar radiation effects on the real-scale massive concrete with wide large plane were reviewed through the analytical method. In this study, the measured temperatures at the real scale structure and the analysis results of concrete hydration heat were compared. And thermal stress analysis was conducted. Through the analysis, it was found that concrete placement duration, sequence and solar radiation effects should be considered to get the accurate concrete peak temperature, maximum temperature differences and crack index

  3. Effectiveness estimation of camouflage measures with solar radiation and longwave radiation considered

    Energy Technology Data Exchange (ETDEWEB)

    Jung, J.S. [LG Electronics Corporation (Korea); Kauh, S.K. [Seoul National University, Seoul (Korea); Yoo, H.S. [Soongsil University, Seoul (Korea)

    1998-11-01

    Camouflage measures in military purpose utilizes the apparent temperature difference between the target and background, so it is essential to develop thermal analysis program for apparent temperature predictions and to apply some camouflage measures to real military targets for camouflage purpose. In this study, a thermal analysis program including conduction, convection and radiation is developed and the validity of radiation heat transfer terms is examined. The results show that longwave radiation along with solar radiation should be included in order to predict apparent temperature as well as physical temperature exactly. Longwave emissivity variation as an effective camouflage measures is applied to a real M2 tank. From the simulation results, it is found that an effective surface treatment, such as painting of a less emissive material or camouflage, clothing, may provide a temperature similarity or a spatial similarity, resulting in an effective camouflage. (author). 12 refs., 6 figs., 1 tab.

  4. Models for the estimation of diffuse solar radiation for typical cities in Turkey

    International Nuclear Information System (INIS)

    Bakirci, Kadir

    2015-01-01

    In solar energy applications, diffuse solar radiation component is required. Solar radiation data particularly in terms of diffuse component are not readily affordable, because of high price of measurements as well as difficulties in their maintenance and calibration. In this study, new empirical models for predicting the monthly mean diffuse solar radiation on a horizontal surface for typical cities in Turkey are established. Therefore, fifteen empirical models from studies in the literature are used. Also, eighteen diffuse solar radiation models are developed using long term sunshine duration and global solar radiation data. The accuracy of the developed models is evaluated in terms of different statistical indicators. It is found that the best performance is achieved for the third-order polynomial model based on sunshine duration and clearness index. - Highlights: • Diffuse radiation is given as a function of clearness index and sunshine fraction. • The diffuse radiation is an important parameter in solar energy applications. • The diffuse radiation measurement is for limited periods and it is very rare. • The new models can be used to estimate monthly average diffuse solar radiation. • The accuracy of the models is evaluated on the basis of statistical indicators

  5. SOLAR RADIATION ESTIMATION ON BUILDING ROOFS AND WEB-BASED SOLAR CADASTRE

    Directory of Open Access Journals (Sweden)

    G. Agugiaro

    2012-07-01

    Full Text Available The aim of this study is the estimation of solar irradiance on building roofs in complex Alpine landscapes. Very high resolution geometric models of the building roofs are generated by means of advanced automated image matching methods. Models are combined with raster and vector data sources to estimate the incoming solar radiation hitting the roofs. The methodology takes into account for atmospheric effects, site latitude and elevation, slope and aspect of the terrain as well as the effects of shadows cast by surrounding buildings, chimneys, dormers, vegetation and terrain topography. An open source software solution has been developed and applied to a study area located in a mountainous site and containing some 1250 residential, commercial and industrial buildings. The method has been validated by data collected with a pyranometer and results made available through a prototype WebGIS platform.

  6. Comparisons of solar radiation interception, albedo and net radiation as influenced by row orientations of crops

    International Nuclear Information System (INIS)

    Baten, Md.A.; Kon, H.

    1997-01-01

    Field experiments were conducted on soybean (Glycin max L.) in summer and potato (Solanum tuberosum L.) in autumn to evaluate the effect of row orientations of crops on some selected micro meteorological factors during 1994 and 1995. The intercepted solar radiation was the largest in the plants growing in bidirection in summer and it exhibited intermediate trend in autumn as compared to E-W or N-S row orientations. In summer, penetrated solar radiation between two plants and near the stem base of a N-S row was larger than that of E-W row. While in autumn, the observed solar radiation between two plants and near the stem base of a E-W row was markedly larger than that of N-S row. The area weighted mean of penetrated solar radiation was larger in E-W soybean rows but lower in potato rows as compared to N-S row orientations. Soil surface temperature between N-S potato rows was larger than that of E-W potato rows and the upper canopy surface temperature of potato was larger in E-W rows as compared to N-S rows. Net radiation observed over E-W potato rows was larger as compared to N-S potato rows but net radiation measured under canopy of E-W potato rows was smaller than that of in N-S rows. Net radiation measured over N-S soybean rows was larger than that of E-W soybean rows and it was smaller between N-S soybean rows when measured under canopy as compared to E-W rows. The albedo observed over potato was larger over E-W rows as compared to N-S rows. Albedos over soybean canopy showed opposite trend with the albedos observed over potato canopy. It was larger over N-S rows as compared to E-W rows. High harvest index was associated with larger interception of radiation. (author)

  7. Development of Sensor Technology and Its Application for Nuclear Radiation Detection

    International Nuclear Information System (INIS)

    Hiskia

    2007-01-01

    Radiation is energy in the form of waves or moving subatomic particles. Radiation can be ionizing or nonionizing radiation, depending on its effect on atomic matter. Because radiation cannot be seen, felt, tasted, heard or smelled, even at lethal levels, radiations detection devices must be used to alert those exposed to radiation. The measurement of radioactivity in the environment is a regulatory requirement around sites where significant amounts of radioactive materials are used or stored. Recently, advent in microelectronics and material technology has enabled to produce small sensor or microsensor, sensitive, accurate, and integrated in a chip or substrate. Development of radiation sensor technology using thin/thick film and micromachining technique was described in this paper. Indonesian capabilities in radiation sensor research and development and opportunities for commercialization also given. (author)

  8. The Development of Sensor Technology and Application to Detect Nuclear Radiation

    International Nuclear Information System (INIS)

    Hiskia

    2007-01-01

    Radiation is energy in the form of waves or moving subatomic particles. Radiation can be ionizing or non-ionizing radiation, depending on its effect on atomic matter. Because radiation cannot be seen, felt, tasted, heard or smelled, even at lethal levels, radiations detection devices must be used to alert those exposed to radiation. The measurement of radioactivity in the environment is a regulatory requirement around sites where significant amounts of radioactive materials are used or stored. Recently, advent in microelectronics and material technology has enabled to produce small sensor or microsensor, sensitive, accurate, and integrated in a chip or substrate. Development of radiation sensor technology using thin/thick film and micromachining technique was described in this paper. Indonesian capabilities in radiation sensor research and development and opportunities for commercialization also given. (author)

  9. Investigating the Impact of a Solar Eclipse on Atmospheric Radiation

    Science.gov (United States)

    Fender, Josh; Morse, Justin; Ringler, John; Galovich, Cynthia; Kuehn, Charles A.; Semak, Matthew

    2018-06-01

    We present a project that measured atmospheric muon flux as a function of altitude during a total solar eclipse. An auxiliary goal was to design and build a cost-effective muon detection device that is simple enough for those with minimal training to build. The detector is part of a self-contained autonomous payload that is carried to altitude aboard a weather balloon. The detection system consists of three Geiger counters connected to a coincidence circuit. This system, along with internal and external temperature sensors and an altimeter, are controlled by an onboard Arduino Mega microcontroller. An internal frame was constructed to house and protect the payload components using modular 3D-printed parts. The payload was launched during the 2017 solar eclipse from Guernsey, Wyoming, along the path of totality. Initial data analysis indicates that line-of-sight blockage of the sun due to a total eclipse produces a negligible difference in muon flux when compared to the results of previous daytime flights. The successful performance of the payload, its low overall cost, and its ease of use suggest that this project would be well-suited for individuals or groups such as high school or undergraduate science students to reproduce and enhance.

  10. Radiation dosimetry properties of smart-phone CMOS sensors

    International Nuclear Information System (INIS)

    Van Hoey, Olivier; Salavrakos, Alexia; Marques, Antonio; Nagao, Alexandre; Vanhavere, Filip; Cauwels, Vanessa; Nascimento, Luana F.; Willems, Ruben

    2016-01-01

    During the past years, several smart-phone applications have been developed for radiation detection. These applications measure radiation using the smart-phone camera complementary metal-oxide-semiconductor sensor. They are potentially useful for data collection and personal dose assessment in case of a radiological incident. However, it is important to assess these applications. Six applications were tested by means of irradiations with calibrated X-ray and gamma sources. It was shown that the measurement stabilises only after at least 10-25 min. All applications exhibited a flat dose rate response in the studied ambient dose equivalent range from 2 to 1000 μSv h -1 . Most applications significantly over- or underestimate the dose rate or are not calibrated in terms of dose rate. A considerable energy dependence was observed below 100 keV but not for the higher energy range more relevant for incident scenarios. Photon impact angle variation gave a measured signal variation of only about 10 %. (authors)

  11. Nighttime Infrared radiative cooling and opacity inferred by REMS Ground Temperature Sensor Measurements

    Science.gov (United States)

    Martín-Torres, Javier; Paz Zorzano, María; Pla-García, Jorge; Rafkin, Scot; Lepinette, Alain; Sebastián, Eduardo; Gómez-Elvira, Javier; REMS Team

    2013-04-01

    Due to the low density of the Martian atmosphere, the temperature of the surface is controlled primarily by solar heating, and infrared cooling to the atmosphere and space, rather than heat exchange with the atmosphere. In the absence of solar radiation the infrared (IR) cooling, and then the nighttime surface temperatures, are directly controlled by soil termal inertia and atmospheric optical thickness (τ) at infrared wavelengths. Under non-wind conditions, and assuming no processes involving latent heat changes in the surface, for a particular site where the rover stands the main parameter controlling the IR cooling will be τ. The minimal ground temperature values at a fixed position may thus be used to detect local variations in the total dust/aerosols/cloud tickness. The Ground Temperature Sensor (GTS) and Air Temperature Sensor (ATS) in the Rover Environmental Monitoring Station (REMS) on board the Mars Science Laboratory (MSL) Curiosity rover provides hourly ground and air temperature measurements respectively. During the first 100 sols of operation of the rover, within the area of low thermal inertia, the minimal nightime ground temperatures reached values between 180 K and 190 K. For this season the expected frost point temperature is 200 K. Variations of up to 10 K have been observed associated with dust loading at Gale at the onset of the dust season. We will use these measurements together with line-by-line radiative transfer simulations using the Full Transfer By Optimized LINe-by-line (FUTBOLIN) code [Martín-Torres and Mlynczak, 2005] to estimate the IR atmospheric opacity and then dust/cloud coverage over the rover during the course of the MSL mission. Monitoring the dust loading and IR nightime cooling evolution during the dust season will allow for a better understanding of the influence of the atmosphere on the ground temperature and provide ground truth to models and orbiter measurements. References Martín-Torres, F. J. and M. G. Mlynczak

  12. Broken-cloud enhancement of solar radiation absorption

    Energy Technology Data Exchange (ETDEWEB)

    Byrne, R.N. [Science Applications International Corporation, San Diego, CA (United States); Somerville, R.C. [Univ. of California, La Jolla, CA (United States); Subasilar, B. [Curtain Univ. of Technology, Perth (Australia)

    1996-04-01

    Two papers recently published in Science have shown that there is more absorption of solar radiation than estimated by current atmospheric general circulation models (GCMs) and that the discrepancy is associated with cloudy scenes. We have devised a simple model which explains this as an artifact of stochastic radiative transport. We first give a heuristic description, unencumbered by mathematical detail. Consider a simple case with clouds distributed at random within a single level whose upper and lower boundaries are fixed. The solar zenith angle is small to moderate; this is therefore an energetically important case. Fix the average areal liquid water content of the cloud layer, and take the statistics of the cloud distribution to be homogeneous within the layer. Furthermore, assume that all the clouds in the layer have the same liquid water content, constant throughout the cloud, and that apart from their droplet content they are identical to the surrounding clear sky. Let the clouds occupy on the average a fraction p{sub cld} of the volume of the cloudy layer, and let them have a prescribed distribution of sizes about some mean. This is not a fractal distribution, because it has a scale. Cloud shape is unimportant so long as cloud aspect ratios are not far from unity. Take the single-scattering albedo to be unity for the droplets in the clouds. All of the absorption is due to atmospheric gases, so the absorption coefficient at a point is the same for cloud and clear sky. Absorption by droplets is less than 10% effect in the numerical stochastic radiation calculations described below, so it is reasonable to neglect it at this level of idealization.

  13. The use of a sky camera for solar radiation estimation based on digital image processing

    International Nuclear Information System (INIS)

    Alonso-Montesinos, J.; Batlles, F.J.

    2015-01-01

    The necessary search for a more sustainable global future means using renewable energy sources to generate pollutant-free electricity. CSP (Concentrated solar power) and PV (photovoltaic) plants are the systems most in demand for electricity production using solar radiation as the energy source. The main factors affecting final electricity generation in these plants are, among others, atmospheric conditions; therefore, knowing whether there will be any change in the solar radiation hitting the plant's solar field is of fundamental importance to CSP and PV plant operators in adapting the plant's operation mode to these fluctuations. Consequently, the most useful technology must involve the study of atmospheric conditions. This is the case for sky cameras, an emerging technology that allows one to gather sky information with optimal spatial and temporal resolution. Hence, in this work, a solar radiation estimation using sky camera images is presented for all sky conditions, where beam, diffuse and global solar radiation components are estimated in real-time as a novel way to evaluate the solar resource from a terrestrial viewpoint. - Highlights: • Using a sky camera, the solar resource has been estimated for one minute periods. • The sky images have been processed to estimate the solar radiation at pixel level. • The three radiation components have been estimated under all sky conditions. • Results have been presented for cloudless, partially-cloudy and overcast conditions. • For beam and global radiation, the nRMSE value is of about 11% under overcast skies.

  14. The problem of multicollinearity in horizontal solar radiation estimation models and a new model for Turkey

    International Nuclear Information System (INIS)

    Demirhan, Haydar

    2014-01-01

    Highlights: • Impacts of multicollinearity on solar radiation estimation models are discussed. • Accuracy of existing empirical models for Turkey is evaluated. • A new non-linear model for the estimation of average daily horizontal global solar radiation is proposed. • Estimation and prediction performance of the proposed and existing models are compared. - Abstract: Due to the considerable decrease in energy resources and increasing energy demand, solar energy is an appealing field of investment and research. There are various modelling strategies and particular models for the estimation of the amount of solar radiation reaching at a particular point over the Earth. In this article, global solar radiation estimation models are taken into account. To emphasize severity of multicollinearity problem in solar radiation estimation models, some of the models developed for Turkey are revisited. It is observed that these models have been identified as accurate under certain multicollinearity structures, and when the multicollinearity is eliminated, the accuracy of these models is controversial. Thus, a reliable model that does not suffer from multicollinearity and gives precise estimates of global solar radiation for the whole region of Turkey is necessary. A new nonlinear model for the estimation of average daily horizontal solar radiation is proposed making use of the genetic programming technique. There is no multicollinearity problem in the new model, and its estimation accuracy is better than the revisited models in terms of numerous statistical performance measures. According to the proposed model, temperature, precipitation, altitude, longitude, and monthly average daily extraterrestrial horizontal solar radiation have significant effect on the average daily global horizontal solar radiation. Relative humidity and soil temperature are not included in the model due to their high correlation with precipitation and temperature, respectively. While altitude has

  15. Assessment of the solar radiation potential of the Thika and Nairobi ...

    African Journals Online (AJOL)

    This assessment seeks to provide information on the solar energy resource potential of the Thika – Nairobi area essential in the dissemination of Renewable Energy Technologies which are essentially solar photovoltaic and thermal systems. To achieve this, solar radiation data for three stations (Dagoretti Corner, Thika and ...

  16. INSTRUMENTATION FOR MEASURING AND TRANSMISSION THE SOLAR RADIATION THROUGH EARTH’S ATMOSPHERE

    Directory of Open Access Journals (Sweden)

    Alexandru Dan Toma

    2013-07-01

    Full Text Available The Sun's energy is distributed over a broad range of the electromagnetic spectrum and Sun behaves approximately like a "blackbody" radiating at a temperature of about 5800 K with maximum output in the green-yellow part of the visible spectrum, around 500 nm. Not all solar radiation reaching the top of the atmosphere reaches Earth's surface due to a various optical phenomena in regard to solar radiation crossing the Earth’s atmosphere. In order to investigate them, there are two general categories of instruments used to measure the transmission of solar radiation through Earth's atmosphere: instruments that measure radiation from the entire sky and instruments that measure only direct solar radiation. Within each of these categories, instruments can be further subdivided into those that measure radiation over a broad range of wavelengths and those that measure only specific wavelengths.

  17. Convective instability of sludge storage under evaporation and solar radiation

    Science.gov (United States)

    Tsiberkin, Kirill; Tatyana, Lyubimova

    2014-05-01

    The sludge storages are an important part of production cycle at salt manufacturing, water supply, etc. A quality of water in the storage depends on mixing of pure water and settled sediment. One of the leading factors is thermal convection. There are two main mechanisms of the layer instability exist. First, it is instability of water due to evaporation from the free surface [1]. It cools the water from upside, increases the particles concentration and leads to the instability in the near-surface layer. Second, the sediment absorbs a solar radiation and heats the liquid from below making it unstable in the near-bottom area. We assume the initial state is the mechanical equilibrium. The water and sediment particles are motionless, the sediment forms a uniform sludge layer of thickness z0, there are no evaporation and heating by solar energy, and the temperature has a linear profile is determined by fixed upper and bottom temperatures of the layer. Taking into account the evaporation and solar radiation absorption, we obtain a non-stationary solution for the temperature using Fourier series method. The local temperature gradients increases rapidly with time, and local Rayleigh number can be estimated by thermal conduction length Lt: Raloc(z,t) = gβ(δT(z,t)/δz)L4t-/νΞ , Lt ~ √Ξt, (1) where g is gravity acceleration, β, ν and Ξ are thermal volume expansion coefficient, kinematic viscosity and thermal conductivity of the liquid, respectively. Raloc* reaches the critical value at finite time t* and water motion begins. The maximal power of solar radiation in visible band equals 230 Wt/m2 at the latitude of "Uralkalii" salt manufacturer (Berezniki, Perm Region, Russian Federation). We neglect IR and UV radiation because of its huge absorption by water [2]. The evaporation speed is found using results for shallow water reservoir [3] and meteorological data for Berezniki [4]. We get the t*~ 6 · 102 s (10 min) for the layer of 1 m depth and t*~ 2 · 103 s (40

  18. Effects of Solar UV Radiation and Climate Change on Biogeochemical Cycling: Interactions and Feedbacks

    Science.gov (United States)

    Solar UV radiation, climate and other drivers of global change are undergoing significant changes and models forecast that these changes will continue for the remainder of this century. Here we assess the effects of solar UV radiation on biogeochemical cycles and the interactions...

  19. A critical review on the estimation of daily global solar radiation from sunshine duration

    International Nuclear Information System (INIS)

    Yorukoglu, Mehmet; Celik, Ali Naci

    2006-01-01

    Models such as the Angstroem-Prescott equation are used to estimate global solar radiation from sunshine duration. In the literature, researchers investigate either the goodness of the model itself or the goodness of the estimation of global solar radiation based on a set of statistical parameters such as R 2 , RMSE, MBE, MABE, MPE and MAPE. If the former is the objective, then the statistical analysis should naturally be based on H/H o - S/S o (the ratio of daily solar radiation to extraterrestrial daily solar radiation vs. the ratio of sunshine duration to day length). If the latter is investigated, then the statistical analysis should be based on H c - H m (calculated daily solar radiation vs. measured daily solar radiation). A literature survey undertaken in the present article showed that these two data sets are apt to be confused, drawing the statistical parameters to be used in assessment of the estimation model from the latter data set or the vice versa set. The statistical parameters are clearly derived from the basics for both of the data sets, and the inconsistencies caused by this confusion and other factors are exposed. A case study of the estimation models and global solar radiation estimation from sunshine duration is presented using five different models (linear, quadratic, cubic, logarithmic and exponential), which are the most common models used in the literature, based on 6 years long measured hourly global solar radiation data

  20. Transmission components of solar radiation in pine stands in relation to climatic and stand variables

    Science.gov (United States)

    Robert A. Muller

    1971-01-01

    In a new approach, transmission was studied by relating to stand biomass the ratio of incoming solar radiation beneath tree crowns to that within the atmosphere. Several assumptions were used to estimate analytically the various ways in which solar radiation penetrates through crowns of three pine species in northern California. Sunflecks accounted for much of the...

  1. Methods to Estimate Solar Radiation Dosimetry in Coral Reefs Using Remote Sensed, Modeled, and in Situ Data.

    Science.gov (United States)

    Solar irradiance has been increasingly recognized as an important determinant of bleaching in coral reefs, but measurements of solar radiation exposure within coral reefs have been relatively limited. Solar irradiance and diffuse down welling attenuation coefficients (Kd, m-1) we...

  2. A model for calculating hourly global solar radiation from satellite data in the tropics

    International Nuclear Information System (INIS)

    Janjai, S.; Pankaew, P.; Laksanaboonsong, J.

    2009-01-01

    A model for calculating global solar radiation from geostationary satellite data is presented. The model is designed to calculate the monthly average hourly global radiation in the tropics with high aerosol load. This model represents a physical relation between the earth-atmospheric albedo derived from GMS5 satellite data and the absorption and scattering coefficients of various atmospheric constituents. The absorption of solar radiation by water vapour which is important for the tropics, was calculated from ambient temperature and relative humidity. The relationship between the visibility and solar radiation depletion due to aerosols was developed for a high aerosol load environment. This relationship was used to calculate solar radiation depletion by aerosols in the model. The total column ozone from TOMS/EP satellite was employed for the determination of solar radiation absorbed by ozone. Solar radiation from four pyranometer stations was used to formulate the relationship between the satellite band earth-atmospheric albedo and broadband earth-atmospheric albedo required by the model. To test its performance, the model was used to compute the monthly average hourly global radiation at 25 solar radiation monitoring stations in tropical areas in Thailand. It was found that the values of monthly average of hourly global radiations calculated from the model were in good agreement with those obtained from the measurements, with the root mean square difference of 10%. After the validation the model was employed to generate hourly solar radiation maps of Thailand. These maps reveal the diurnal and season variation of solar radiation over the country.

  3. A model for calculating hourly global solar radiation from satellite data in the tropics

    Energy Technology Data Exchange (ETDEWEB)

    Janjai, S.; Pankaew, P.; Laksanaboonsong, J. [Solar Energy Research Laboratory, Department of Physics, Faculty of Science, Silpakorn University, Nakhon Pathom 73000 (Thailand)

    2009-09-15

    A model for calculating global solar radiation from geostationary satellite data is presented. The model is designed to calculate the monthly average hourly global radiation in the tropics with high aerosol load. This model represents a physical relation between the earth-atmospheric albedo derived from GMS5 satellite data and the absorption and scattering coefficients of various atmospheric constituents. The absorption of solar radiation by water vapour which is important for the tropics, was calculated from ambient temperature and relative humidity. The relationship between the visibility and solar radiation depletion due to aerosols was developed for a high aerosol load environment. This relationship was used to calculate solar radiation depletion by aerosols in the model. The total column ozone from TOMS/EP satellite was employed for the determination of solar radiation absorbed by ozone. Solar radiation from four pyranometer stations was used to formulate the relationship between the satellite band earth-atmospheric albedo and broadband earth-atmospheric albedo required by the model. To test its performance, the model was used to compute the monthly average hourly global radiation at 25 solar radiation monitoring stations in tropical areas in Thailand. It was found that the values of monthly average of hourly global radiations calculated from the model were in good agreement with those obtained from the measurements, with the root mean square difference of 10%. After the validation the model was employed to generate hourly solar radiation maps of Thailand. These maps reveal the diurnal and season variation of solar radiation over the country. (author)

  4. Solar radiation availability for tomato cropping during winter in Santa Maria, RS, Brazil

    International Nuclear Information System (INIS)

    Estefanel, V.; Buriol, G.A.; Andriolo, J.L.; Lima, C.P.; Luzzi, N.

    1998-01-01

    The probability of occurrence of days with solar radiation bellow the critical value for the development of tomato inside greenhouse in Santa Maria, Rio Grande do Sul State, were calculated during May, June, July and August. It was considered the flue density of solar radiation of 200 cal cm -2 dia -1 as the lowest value to tomato growth and 180 cal cm -2 dia -1 as the low value reference of solar radiation for crop growth. Daily values of solar radiation were estimated by sunshine duration during the time period from 1912 to 1996. Results showed that the availability of solar radiation in Santa Maria was lower than the required by tomato crop inside plastic greenhouse during Winter, mainly in June and July. (author) [pt

  5. Estimating the horizontal diffuse solar radiation over the Central Anatolia Region of Turkey

    International Nuclear Information System (INIS)

    Aras, Haydar; Balli, Ozgur; Hepbasli, Arif

    2006-01-01

    The main objective of the present study is to develop new hybrid models to predict the monthly average daily diffuse solar radiation on a horizontal surface over Turkey's Central Anatolia Region (CAR), which covers the 12 provinces (Afyon, Ankara, Cankiri, Corum, Eskisehir, Kayseri, Kirsehir, Konya, Nevsehir, Nigde, Sivas and Yozgat), as an example. The models proposed by many investigators to estimate the diffuse solar radiation were reviewed. Although the global solar radiation and sunshine duration have been measured by the Turkish State Meteorological Service (DMI) over all the country since 1964, the diffuse solar radiation has not been measured. The twelve new hybrid models for estimating the monthly average daily diffuse solar radiation on a horizontal surface in the CAR were validated, and thus, the most accurate model was selected for guiding future projects

  6. Radiative transfer model for estimation of global solar radiation; Modelo de transferencia radiativa para la estimacion de la radiacion solar global

    Energy Technology Data Exchange (ETDEWEB)

    Pettazzi, A.; Sabon, C. S.; Souto, G. J. A.

    2004-07-01

    In this work, the efficiency of a radiative transfer model in estimating the annual solar global radiation has been evaluated, over different locations at Galicia, Spain, in clear sky periods. Due to its quantitative significance, special attention has been focused on the analysis of the influence of visibility over the global radiation. By comparison of both estimated and measured global solar radiation along year 2002, a typical annual visibility series was obtained over every location. These visibility values has been analysed in order to identify patterns and typical values, in order to be used to estimate the global solar radiation along a different year. Validation was done over the year 2003, obtaining an annual estimation less than 10 % different to the measured value. (Author)

  7. A Comparison of Satellite Based, Modeled Derived Daily Solar Radiation Data with Observed Data for the Continental US

    Science.gov (United States)

    White, Jeffrey W.; Hoogenboom, Gerrit; Wilkens, Paul W.; Stackhouse, Paul W., Jr.; Hoell, James M.

    2010-01-01

    Many applications of simulation models and related decision support tools for agriculture and natural resource management require daily meteorological data as inputs. Availability and quality of such data, however, often constrain research and decision support activities that require use of these tools. Daily solar radiation (SRAD) data are especially problematic because the instruments require electronic integrators, accurate sensors are expensive, and calibration standards are seldom available. The Prediction Of Worldwide Energy Resources (NASA/POWER; power.larc.nasa.gov) project at the NASA Langley Research Center estimates daily solar radiation based on data that are derived from satellite observations of outgoing visible radiances and atmospheric parameters based upon satellite observations and assimilation models. The solar data are available for a global 1 degree x 1 degree coordinate grid. SRAD can also be estimated based on attenuation of extraterrestrial radiation (Q0) using daily temperature and rainfall data to estimate the optical thickness of the atmosphere. This study compares daily solar radiation data from NASA/POWER (SRADNP) with instrument readings from 295 stations (SRADOB), as well as with values that were estimated with the WGENR solar generator. WGENR was used both with daily temperature and precipitation records from the stations reporting solar data and records from the NOAA Cooperative Observer Program (COOP), thus providing two additional sources of solar data, SRADWG and SRADCO. Values of SRADNP for different grid cells consistently showed higher correlations (typically 0.85 to 0.95) with SRADOB data than did SRADWG or SRADCO for sites within the corresponding cells. Mean values of SRADOB, SRADWG and SRADNP for sites within a grid cell usually were within 1 MJm-2d-1 of each other, but NASA/POWER values averaged 1.1 MJm-2d-1 lower than SRADOB. The magnitude of this bias was greater at lower latitudes and during summer months and may be at

  8. Sensitivity analysis of numerical weather prediction radiative schemes to forecast direct solar radiation over Australia

    Science.gov (United States)

    Mukkavilli, S. K.; Kay, M. J.; Taylor, R.; Prasad, A. A.; Troccoli, A.

    2014-12-01

    The Australian Solar Energy Forecasting System (ASEFS) project requires forecasting timeframes which range from nowcasting to long-term forecasts (minutes to two years). As concentrating solar power (CSP) plant operators are one of the key stakeholders in the national energy market, research and development enhancements for direct normal irradiance (DNI) forecasts is a major subtask. This project involves comparing different radiative scheme codes to improve day ahead DNI forecasts on the national supercomputing infrastructure running mesoscale simulations on NOAA's Weather Research & Forecast (WRF) model. ASEFS also requires aerosol data fusion for improving accurate representation of spatio-temporally variable atmospheric aerosols to reduce DNI bias error in clear sky conditions over southern Queensland & New South Wales where solar power is vulnerable to uncertainities from frequent aerosol radiative events such as bush fires and desert dust. Initial results from thirteen years of Bureau of Meteorology's (BOM) deseasonalised DNI and MODIS NASA-Terra aerosol optical depth (AOD) anomalies demonstrated strong negative correlations in north and southeast Australia along with strong variability in AOD (~0.03-0.05). Radiative transfer schemes, DNI and AOD anomaly correlations will be discussed for the population and transmission grid centric regions where current and planned CSP plants dispatch electricity to capture peak prices in the market. Aerosol and solar irradiance datasets include satellite and ground based assimilations from the national BOM, regional aerosol researchers and agencies. The presentation will provide an overview of this ASEFS project task on WRF and results to date. The overall goal of this ASEFS subtask is to develop a hybrid numerical weather prediction (NWP) and statistical/machine learning multi-model ensemble strategy that meets future operational requirements of CSP plant operators.

  9. Online educative activities for solar ultraviolet radiation based on measurements of cloud amount and solar exposures.

    Science.gov (United States)

    Parisi, A V; Downs, N; Turner, J; Amar, A

    2016-09-01

    A set of online activities for children and the community that are based on an integrated real-time solar UV and cloud measurement system are described. These activities use the functionality of the internet to provide an educative tool for school children and the public on the influence of cloud and the angle of the sun above the horizon on the global erythemal UV or sunburning UV, the diffuse erythemal UV, the global UVA (320-400nm) and the vitamin D effective UV. Additionally, the units of UV exposure and UV irradiance are investigated, along with the meaning and calculation of the UV index (UVI). This research will help ensure that children and the general public are better informed about sun safety by improving their personal understanding of the daily and the atmospheric factors that influence solar UV radiation and the solar UV exposures of the various wavebands in the natural environment. The activities may correct common misconceptions of children and the public about UV irradiances and exposure, utilising the widespread reach of the internet to increase the public's awareness of the factors influencing UV irradiances and exposures in order to provide clear information for minimizing UV exposure, while maintaining healthy, outdoor lifestyles. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Intelligent sensors and actuators. Autonomous solar input and wireless data transmission. Intelligente Sensoren und Aktoren. Autonome Solar-Versorgung und drahtlose Datenuebertragung

    Energy Technology Data Exchange (ETDEWEB)

    Kuntz, W; Mores, R [Transferzentrum Furtwangen (Germany)

    1991-09-03

    Sensors are referred to as intelligent if they evaluate the results immediately internally. A micro server as a rule is responsible for it. Sensors can be implemented with extremely low power dissipation. If they are supplied with energy over optical waveguide, they can even work potentialfree. Battery-fed or solar-fed intelligent sensors with data transmission viaer infrared light or UHF record measured values with standard time. They are bus-capable and allow a mobile application without interfering cables. (orig.).

  11. Develop of BiI3 sensors for imagenology of radiations to ambient temperature

    International Nuclear Information System (INIS)

    Aguiar, I.

    2008-01-01

    The mastery refers to the obtention of images with radiations. The subject in study to be used as sensor of those radiations in the triodide of bismuth, since its properties makes it appropriate for the detections of ionizing and infrared radiation

  12. Prediction of monthly average global solar radiation based on statistical distribution of clearness index

    International Nuclear Information System (INIS)

    Ayodele, T.R.; Ogunjuyigbe, A.S.O.

    2015-01-01

    In this paper, probability distribution of clearness index is proposed for the prediction of global solar radiation. First, the clearness index is obtained from the past data of global solar radiation, then, the parameters of the appropriate distribution that best fit the clearness index are determined. The global solar radiation is thereafter predicted from the clearness index using inverse transformation of the cumulative distribution function. To validate the proposed method, eight years global solar radiation data (2000–2007) of Ibadan, Nigeria are used to determine the parameters of appropriate probability distribution for clearness index. The calculated parameters are then used to predict the future monthly average global solar radiation for the following year (2008). The predicted values are compared with the measured values using four statistical tests: the Root Mean Square Error (RMSE), MAE (Mean Absolute Error), MAPE (Mean Absolute Percentage Error) and the coefficient of determination (R"2). The proposed method is also compared to the existing regression models. The results show that logistic distribution provides the best fit for clearness index of Ibadan and the proposed method is effective in predicting the monthly average global solar radiation with overall RMSE of 0.383 MJ/m"2/day, MAE of 0.295 MJ/m"2/day, MAPE of 2% and R"2 of 0.967. - Highlights: • Distribution of clearnes index is proposed for prediction of global solar radiation. • The clearness index is obtained from the past data of global solar radiation. • The parameters of distribution that best fit the clearness index are determined. • Solar radiation is predicted from the clearness index using inverse transformation. • The method is effective in predicting the monthly average global solar radiation.

  13. Cyclotron Line in Solar Microwave Radiation by Radio Telescope RATAN-600 Observations of the Solar Active Region NOAA 12182

    Science.gov (United States)

    Peterova, N. G.; Topchilo, N. A.

    2017-12-01

    This paper presents the results of observation of a rare phenomenon—a narrowband increase in the brightness of cyclotron radiation of one of the structural details of a radio source located in the solar corona above the solar active region NOAA 12182 in October 2014 at a frequency of 4.2 ± 0.1 GHz. The brightness of radiation in the maximum of the phenomenon has reached 10 MK; its duration was equal to 3 s. The exact location of the source of the narrowband cyclotron radiation is indicated: it is a corona above a fragmented (4-nuclear) sunspot, on which a small UV flare loop was closed.

  14. On protection of freedom's solar dynamic radiator from the orbital debris environment. Part 2

    International Nuclear Information System (INIS)

    Rhatigan, J.L.

    1992-01-01

    In this paper, recent progress to better understand the environmental threat of micrometeoroid and space debris to the solar dynamic radiator for the Space Station Freedom power system is reported. The objective was to define a design which would perform to survivability requirements over the expected lifetime of the radiator. A previous paper described the approach developed to assess on-orbit survivability of the solar dynamic radiator due to micrometeoroid and space debris impacts. Preliminary analyses were presented to quantify the solar dynamic radiator survivability. These included the type of particle and particle population expected to defeat the radiator bumpering. Results of preliminary hypervelocity impact (HVI) testing performed on radiator panel samples were also presented. This paper presents results of a more extensive test program undertaken to further define the response of the solar dynamic radiator to HVI. Tests were conducted on representative radiator panels (under ambient, nonoperating conditions) over a range of particle size, particle density, impact angle, and impact velocity. Target parameters were also varied. Data indicate that analytical penetration predictions are conservative (i.e., pessimistic) for the specific configuration of the solar dynamic radiator. Test results are used to define more rigorously the solar dynamic radiator reliability with respect to HVI. Test data, analyses, and survivability results are presented

  15. Solar Passive Modification Increase Radiation Safety Standards Inside Accelerator Building

    International Nuclear Information System (INIS)

    Eid, A. F.; Keshk, A. B.

    2010-01-01

    Irradiation processing by accelerated electrons is considering one of the most important and useful industrial irradiation treatments. It is depending on two principle attachment elements which are architecture of irradiation building and the accelerator characteristic that was arranged inside irradiation building. Negative environmental measurements were recorded inside the main building and were exceeded the international standards (humidity, air speed, high thermal effects and ozone concentration). The study showed that it is essential to improve the natural environmental standards inside the main irradiation building in order to improve the work environment and to reduce ozone concentration from 220 ppb to international standard. The main goals and advantages were achieved by using environmental architecture (desert architecture) indoor the irradiation building. The work depends on passive solar system which is economic, same architectural elements, comfort / health, and radiation safety, and without mechanical means. The experimental work was accomplished under these modifications. The registered results of various environmental concentrations have proved their normal standards.

  16. [Solar radiation exposure in agriculture: an underestimated risk].

    Science.gov (United States)

    Gobba, F

    2012-01-01

    Solar Radiation (SR) is a major occupational risk in agriculture, mainly related to its ultraviolet (UV) component. Available data show that UV occupational limits are frequently exceeded in these workers, resulting in an increased occupational risk of various acute and chronic effects, mainly to skin and to the eye. One of the foremost is the carcinogenic effect: SR is indeed included in Group 1 IARC (carcinogenic to humans). UV exposure is related to an increase of the incidence of basal cell carcinoma and squamous cell carcinoma of the skin, and cutaneous malignant melanoma (CMM). The incidence of these tumors, especially CMM, is constantly increasing in Caucasians in the last 50 years. As a conclusion, an adequate evaluation of the occupational risk related to SR, and adequate preventive measures are essential in agriculture. The role of the Occupational Physician in prevention is fundamental.

  17. Solar radiation pressure resonances in Low Earth Orbits

    Science.gov (United States)

    Alessi, Elisa Maria; Schettino, Giulia; Rossi, Alessandro; Valsecchi, Giovanni B.

    2018-01-01

    The aim of this work is to highlight the crucial role that orbital resonances associated with solar radiation pressure can have in Low Earth Orbit. We review the corresponding literature, and provide an analytical tool to estimate the maximum eccentricity which can be achieved for well-defined initial conditions. We then compare the results obtained with the simplified model with the results obtained with a more comprehensive dynamical model. The analysis has important implications both from a theoretical point of view, because it shows that the role of some resonances was underestimated in the past, and also from a practical point of view in the perspective of passive deorbiting solutions for satellites at the end-of-life.

  18. Radiation effects in heteroepitaxial InP solar cells

    Science.gov (United States)

    Weinberg, I.; Curtis, H. B.; Swartz, C. K.; Brinker, D. J.; Vargas-Aburto, C.

    1993-01-01

    Heteroepitaxial InP solar cells, with GaAs substrates, were irradiated by 0.5 and 3 MeV protons and their performance, temperature dependency, and carrier removal rates determined as a function of fluence. The radiation resistance of the present cells was significantly greater than that of non-heteroepitaxial InP cells at both proton energies. A clear difference in the temperature dependency of V(sub oc), was observed between heteroepitaxial and homoepitaxial InP cells. The analytically predicted dependence of dV(sub oc)/dT on Voc was confirmed by the fluence dependence of these quantities. Carrier removal was observed to increase with decreasing proton energy. The results obtained for performance and temperature dependency were attributed to the high dislocation densities present in the heteroepitaxial cells while the energy dependence of carrier removal was attributed to the energy dependence of proton range.

  19. Outdoor Exposure to Solar Ultraviolet Radiation and Legislation in Brazil.

    Science.gov (United States)

    Silva, Abel A

    2016-06-01

    The total ozone column of 265 ± 11 Dobson Units in the tropical-equatorial zones and 283 ± 16 Dobson Units in the subtropics of Brazil are among the lowest on Earth, and as a result, the prevalence of skin cancer due to solar ultraviolet radiation is among the highest. Daily erythemal doses in Brazil can be over 7,500 J m. Erythemal dose rates on cloudless days of winter and summer are typically about 0.147 W m and 0.332 W m, respectively. However, radiation enhancement events yielded by clouds have been reported with erythemal dose rates of 0.486 W m. Daily doses of the diffuse component of erythemal radiation have been determined with values of 5,053 J m and diffuse erythemal dose rates of 0.312 W m. Unfortunately, Brazilians still behave in ways that lead to overexposure to the sun. The annual personal ultraviolet radiation ambient dose among Brazilian youths can be about 5.3%. Skin cancer in Brazil is prevalent, with annual rates of 31.6% (non-melanoma) and 1.0% (melanoma). Governmental and non-governmental initiatives have been taken to increase public awareness of photoprotection behaviors. Resolution #56 by the Agência Nacional de Vigilância Sanitária has banned tanning devices in Brazil. In addition, Projects of Law (PL), like PL 3730/2004, propose that the Sistema Único de Saúde should distribute sunscreen to members of the public, while PL 4027/2012 proposes that employers should provide outdoor workers with sunscreen during professional outdoor activities. Similar laws have already been passed in some municipalities. These are presented and discussed in this study.

  20. Experimental checking results of mathematical modeling of the radiation environment sensor based on diamond detectors

    International Nuclear Information System (INIS)

    Gladchenkov, E V; Kolyubin, V A; Nedosekin, P G; Zaharchenko, K V; Ibragimov, R F; Kadilin, V V; Tyurin, E M

    2017-01-01

    Were conducted a series of experiments, the purpose of which had to verify the mathematical model of the radiation environment sensor. Theoretical values of the beta particles count rate from 90 Sr - 90 Y source registered by radiation environment sensor was compared with the experimental one. Theoretical (calculated) count rate of beta particles was found with using the developed mathematical model of the radiation environment sensor. Deviation of the calculated values of the beta particle count rate does not exceed 10% from the experimental. (paper)

  1. Investigating work-related neoplasia associated with solar radiation.

    Science.gov (United States)

    Turner, S; Forman, S D; McNamee, R; Wilkinson, S M; Agius, R

    2015-01-01

    Both solar and non-solar exposures associated with occupation and work tasks have been reported as skin carcinogens. In the UK, there are well-established surveillance schemes providing relevant information, including when exposures took place, occupation, location of work and dates of symptom onset and diagnosis. To add to the evidence on work-related skin neoplasia, including causal agents, geographical exposure and time lag between exposure and diagnosis. This study investigated incident case reports of occupational skin disease originating from clinical specialists in dermatology reporting to a UK-wide surveillance scheme (EPIDERM) by analysing case reports of skin neoplasia from 1996 to 2012 in terms of diagnosis, employment, suspected causal agent and symptom onset. The suspected causal agent was 'sun/sunlight/ultraviolet light' in 99% of the reported work-related skin neoplasia cases. Most cases reported (91%) were in males, and the majority (62%) were aged over 65 at the time of reporting. More detailed information on exposure was available for 42% of the cases, with the median time from exposure to symptom onset ranging from 44 (melanoma) to 57 (squamous cell carcinoma) years. Irrespective of diagnostic category, the median duration of exposure to 'sun/sunlight/ultraviolet light' appeared longer where exposures occurred in the UK (range 39-51 years) rather than outside the UK (range 2.5-6.5 years). It is important to provide effective information about skin protection to workers exposed to solar radiation, especially to outdoor workers based outside the UK. © The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Sensitivity of APSIM/ORYZA model due to estimation errors in solar radiation

    Directory of Open Access Journals (Sweden)

    Alexandre Bryan Heinemann

    2012-01-01

    Full Text Available Crop models are ideally suited to quantify existing climatic risks. However, they require historic climate data as input. While daily temperature and rainfall data are often available, the lack of observed solar radiation (Rs data severely limits site-specific crop modelling. The objective of this study was to estimate Rs based on air temperature solar radiation models and to quantify the propagation of errors in simulated radiation on several APSIM/ORYZA crop model seasonal outputs, yield, biomass, leaf area (LAI and total accumulated solar radiation (SRA during the crop cycle. The accuracy of the 5 models for estimated daily solar radiation was similar, and it was not substantially different among sites. For water limited environments (no irrigation, crop model outputs yield, biomass and LAI was not sensitive for the uncertainties in radiation models studied here.

  3. Solar Extreme UV radiation and quark nugget dark matter model

    Energy Technology Data Exchange (ETDEWEB)

    Zhitnitsky, Ariel, E-mail: arz@phas.ubc.ca [Department of Physics and Astronomy, University of British Columbia, Vancouver, B.C. V6T 1Z1 (Canada)

    2017-10-01

    We advocate the idea that the surprising emission of extreme ultra violet (EUV) radiation and soft x-rays from the Sun are powered externally by incident dark matter (DM) particles. The energy and the spectral shape of this otherwise unexpected solar irradiation is estimated within the quark nugget dark matter model. This model was originally invented as a natural explanation of the observed ratio Ω{sub dark} ∼ Ω{sub visible} when the DM and visible matter densities assume the same order of magnitude values. This generic consequence of the model is a result of the common origin of both types of matter which are formed during the same QCD transition and both proportional to the same fundamental dimensional parameter Λ{sub QCD}. We also present arguments suggesting that the transient brightening-like 'nanoflares' in the Sun may be related to the annihilation events which inevitably occur in the solar atmosphere within this dark matter scenario.

  4. Short-range solar radiation forecasts over Sweden

    Directory of Open Access Journals (Sweden)

    T. Landelius

    2018-04-01

    Full Text Available In this article the performance for short-range solar radiation forecasts by the global deterministic and ensemble models from the European Centre for Medium-Range Weather Forecasts (ECMWF is compared with an ensemble of the regional mesoscale model HARMONIE-AROME used by the national meteorological services in Sweden, Norway and Finland. Note however that only the control members and the ensemble means are included in the comparison. The models resolution differs considerably with 18 km for the ECMWF ensemble, 9 km for the ECMWF deterministic model, and 2.5 km for the HARMONIE-AROME ensemble.The models share the same radiation code. It turns out that they all underestimate systematically the Direct Normal Irradiance (DNI for clear-sky conditions. Except for this shortcoming, the HARMONIE-AROME ensemble model shows the best agreement with the distribution of observed Global Horizontal Irradiance (GHI and DNI values. During mid-day the HARMONIE-AROME ensemble mean performs best. The control member of the HARMONIE-AROME ensemble also scores better than the global deterministic ECMWF model. This is an interesting result since mesoscale models have so far not shown good results when compared to the ECMWF models.Three days with clear, mixed and cloudy skies are used to illustrate the possible added value of a probabilistic forecast. It is shown that in these cases the mesoscale ensemble could provide decision support to a grid operator in terms of forecasts of both the amount of solar power and its probabilities.

  5. Laplace plane modifications arising from solar radiation pressure

    Energy Technology Data Exchange (ETDEWEB)

    Rosengren, Aaron J.; Scheeres, Daniel J., E-mail: aaron.rosengren@colorado.edu [ADepartment of Aerospace Engineering Sciences, University of Colorado at Boulder, Boulder, CO 80309 (United States)

    2014-05-01

    The dynamical effects of solar radiation pressure (SRP) in the solar system have been rigorously studied since the early 1900s. This non-gravitational perturbation plays a significant role in the evolution of dust particles in circumplanetary orbits, as well as in the orbital motion about asteroids and comets. For gravitationally dominated orbits, SRP is negligible and the resulting motion is largely governed by the oblateness of the primary and the attraction of the Sun. The interplay between these gravitational perturbations gives rise to three mutually perpendicular planes of equilibrium for circular satellite orbits. The classical Laplace plane lies between the equatorial and orbital planes of the primary, and is the mean reference plane about whose axis the pole of a satellite's orbit precesses. From a previously derived solution for the secular motion of an orbiter about a small body in a SRP dominated environment, we find that SRP acting alone will cause an initially circular orbit to precess around the pole of the primary's heliocentric orbital plane. When the gravitational and non-gravitational perturbations act in concert, the resulting equilibrium planes turn out to be qualitatively different, in some cases, from those obtained without considering the radiation pressure. The warping of the surfaces swept out by the modified equilibria as the semi-major axis varies depends critically on the cross-sectional area of the body exposed. These results, together with an adiabatic invariance argument on Poynting-Robertson drag, provide a natural qualitative explanation for the initial albedo dichotomy of Saturn's moon, Iapetus.

  6. Bridging the Radiative Transfer Models for Meteorology and Solar Energy Applications

    Science.gov (United States)

    Xie, Y.; Sengupta, M.

    2017-12-01

    Radiative transfer models are used to compute solar radiation reaching the earth surface and play an important role in both meteorology and solar energy studies. Therefore, they are designed to meet the needs of specialized applications. For instance, radiative transfer models for meteorology seek to provide more accurate cloudy-sky radiation compared to models used in solar energy that are geared towards accuracy in clear-sky conditions associated with the maximum solar resource. However, models for solar energy applications are often computationally faster, as the complex solution of the radiative transfer equation is parameterized by atmospheric properties that can be acquired from surface- or satellite-based observations. This study introduces the National Renewable Energy Laboratory's (NREL's) recent efforts to combine the advantages of radiative transfer models designed for meteorology and solar energy applictions. A fast all-sky radiation model, FARMS-NIT, was developed to efficiently compute narrowband all-sky irradiances over inclined photovoltaic (PV) panels. This new model utilizes the optical preperties from a solar energy model, SMARTS, to computes surface radiation by considering all possible paths of photon transmission and the relevent scattering and absorption attenuation. For cloudy-sky conditions, cloud bidirectional transmittance functions (BTDFs) are provided by a precomputed lookup table (LUT) by LibRadtran. Our initial results indicate that FARMS-NIT has an accuracy that is similar to LibRadtran, a highly accurate multi-stream model, but is significantly more efficient. The development and validation of this model will be presented.

  7. Study of planar pixel sensors hardener to radiations for the upgrade of the ATLAS vertex detector

    International Nuclear Information System (INIS)

    Benoit, M.

    2011-05-01

    In this work, we present a study, using TCAD (Technology Computer-Assisted Design) simulation, of the possible methods of designing planar pixel sensors by reducing their inactive area and improving their radiation hardness for use in the Insertable B-Layer (IBL) project and for SLHC upgrade phase for the ATLAS experiment. Different physical models available have been studied to develop a coherent model of radiation damage in silicon that can be used to predict silicon pixel sensor behavior after exposure to radiation. The Multi-Guard Ring Structure, a protection structure used in pixel sensor design was studied to obtain guidelines for the reduction of inactive edges detrimental to detector operation while keeping a good sensor behavior through its lifetime in the ATLAS detector. A campaign of measurement of the sensor process parameters and electrical behavior to validate and calibrate the TCAD simulation models and results are also presented. A model for diode charge collection in highly irradiated environment was developed to explain the high charge collection observed in highly irradiated devices. A simple planar pixel sensor digitization model to be used in test beam and full detector system is detailed. It allows for easy comparison between experimental data and prediction by the various radiation damage models available. The digitizer has been validated using test beam data for unirradiated sensors and can be used to produce the first full scale simulation of the ATLAS detector with the IBL that include sensor effects such as slim edge and thinning of the sensor. (author)

  8. Sensitivity of APSIM/ORYZA model due to estimation errors in solar radiation

    OpenAIRE

    Alexandre Bryan Heinemann; Pepijn A.J. van Oort; Diogo Simões Fernandes; Aline de Holanda Nunes Maia

    2012-01-01

    Crop models are ideally suited to quantify existing climatic risks. However, they require historic climate data as input. While daily temperature and rainfall data are often available, the lack of observed solar radiation (Rs) data severely limits site-specific crop modelling. The objective of this study was to estimate Rs based on air temperature solar radiation models and to quantify the propagation of errors in simulated radiation on several APSIM/ORYZA crop model seasonal outputs, yield, ...

  9. Acute Radiation Effects Resulting from Exposure to Solar Particle Event-Like Radiation

    Science.gov (United States)

    Kennedy, Ann; Cengel, Keith

    2012-07-01

    A major solar particle event (SPE) may place astronauts at significant risk for the acute radiation syndrome (ARS), which may be exacerbated when combined with other space flight stressors, such that the mission or crew health may be compromised. The National Space Biomedical Research Institute (NSBRI) Center of Acute Radiation Research (CARR) is focused on the assessment of risks of adverse biological effects related to the ARS in animal models exposed to space flight stressors combined with the types of radiation expected during an SPE. As part of this program, FDA-approved drugs that may prevent and/or mitigate ARS symptoms are being evaluated. The CARR studies are focused on the adverse biological effects resulting from exposure to the types of radiation, at the appropriate energies, doses and dose-rates, present during an SPE (and standard reference radiations, gamma rays or electrons). The ARS is a phased syndrome which often includes vomiting and fatigue. Other acute adverse biologic effects of concern are the loss of hematopoietic cells, which can result in compromised bone marrow and immune cell functions. There is also concern for skin damage from high SPE radiation doses, including burns, and resulting immune system dysfunction. Using 3 separate animal model systems (ferrets, mice and pigs), the major ARS biologic endpoints being evaluated are: 1) vomiting/retching and fatigue, 2) hematologic changes (with focus on white blood cells) and immune system changes resulting from exposure to SPE radiation with and without reduced weightbearing conditions, and 3) skin injury and related immune system functions. In all of these areas of research, statistically significant adverse health effects have been observed in animals exposed to SPE-like radiation. Countermeasures for the management of ARS symptoms are being evaluated. New research findings from the past grant year will be discussed. Acknowledgements: This research is supported by the NSBRI Center of Acute

  10. Radiation resistant low bandgap InGaAsP solar cell for multi-junction solar cells

    International Nuclear Information System (INIS)

    Khan, Aurangzeb; Yamaguchi, Masafumi; Dharmaras, Nathaji; Yamada, Takashi; Tanabe, Tatsuya; Takagishi, Shigenori; Itoh, Hisayoshi; Ohshima, Takeshi

    2001-01-01

    We have explored the superior radiation tolerance of metal organic chemical vapor deposition (MOCVD) grown, low bandgap, (0.95eV) InGaAsP solar cells as compared to GaAs-on-Ge cells, after 1 MeV electron irradiation. The minority carrier injection due to forward bias and light illumination under low concentration ratio, can lead to enhanced recovery of radiation damage in InGaAsP n + -p junction solar cells. An injection anneal activation energy (0.58eV) of the defects involved in damage/recovery of the InGaAsP solar cells has been estimated from the resultant recovery of the solar cell properties following minority carrier injection. The results suggest that low bandgap radiation resistant InGaAsP (0.95eV) lattice matched to InP substrates provide an alternative to use as bottom cells in multi-junction solar cells instead of less radiation ressitant conventional GaAs based solar cells for space applications. (author)

  11. Observation and calculation of the solar radiation on the Tibetan Plateau

    International Nuclear Information System (INIS)

    Liu Jiandong; Liu Jingmiao; Linderholm, Hans W.; Chen Deliang; Yu Qiang; Wu Dingrong; Haginoya, Shigenori

    2012-01-01

    Highlights: ► Five years of continuous solar-radiation observations on the Tibetan Plateau were analyzed. ► Eight solar models were calibrated and validated in this highland region. ► A strategy for calculating solar radiation on the Tibetan Plateau was presented. - Abstract: Distribution of solar radiation is vital to locate the most suitable regions for harvesting solar energy, but solar radiation is only observed at few stations due to high costs and difficult maintenance. From 2001 to 2005, a set of pyranometer instruments were set up in Gaize, on the Tibetan Plateau, to test the hypothesis of high solar-radiation levels in this region, and find a suitable method for estimating the radiation. Over the 5-year observation period, the average daily radiation was 21 MJ m −2 day −1 with maximum daily values of 27 MJ m −2 day −1 occurring in June and minimum values of 14 MJ m −2 day −1 in December, which is much higher than those measured in other regions at similar latitudes. The observational data were used to validate a set of radiation models: five sunshine based and three temperature based. The results showed that of the five sunshine-based models, a newly developed “comprehensive” model performed the best, but that the “vapor revised Angstrom model” was recommended to use for its simplicity and easy operation. The temperature-based models performed worse than the sunshine-based ones, where the Wu model is to be preferred if a temperature-based model is the only option. Moreover, it was shown that when estimating the solar radiation based on time-dependent coefficients, consideration of the seasonal variation of the coefficients has little predictive value and is thus unnecessary. Based on the results of this study, a strategy for the calculation of solar radiation on the Tibetan Plateau was made for potential users.

  12. UD-WCMA: An Energy Estimation and Forecast Scheme for Solar Powered Wireless Sensor Networks

    KAUST Repository

    Dehwah, Ahmad H.

    2017-04-11

    Energy estimation and forecast represents an important role for energy management in solar-powered wireless sensor networks (WSNs). In general, the energy in such networks is managed over a finite time horizon in the future based on input solar power forecasts to enable continuous operation of the WSNs and achieve the sensing objectives while ensuring that no node runs out of energy. In this article, we propose a dynamic version of the weather conditioned moving average technique (UD-WCMA) to estimate and predict the variations of the solar power in a wireless sensor network. The presented approach combines the information from the real-time measurement data and a set of stored profiles representing the energy patterns in the WSNs location to update the prediction model. The UD-WCMA scheme is based on adaptive weighting parameters depending on the weather changes which makes it flexible compared to the existing estimation schemes without any precalibration. A performance analysis has been performed considering real irradiance profiles to assess the UD-WCMA prediction accuracy. Comparative numerical tests to standard forecasting schemes (EWMA, WCMA, and Pro-Energy) shows the outperformance of the new algorithm. The experimental validation has proven the interesting features of the UD-WCMA in real time low power sensor nodes.

  13. Celulas solares e sensores de filme fino de silicio depositados sobre substratos flexiveis =

    Science.gov (United States)

    Pinto, Emilio Sergio Marins Vieira

    Celulas solares flexiveis de filmes finos de silicio sao geralmente fabricadas a baixa temperatura sobre substratos de plastico ou a mais elevadas temperaturas sobre folhas de aco. Esta tese reporta o estudo da deposicao de filmes finos sobre diferentes substratos de plastico, transparentes e coloridos, para celulas solares do tipo sobrestrato e substrato, respectivamente. Como objetivo co-lateral, os filmes dopados depositados sobre plastico foram usados como sensores de deformacao, utilizando as suas propriedades piezo-resistivas. Elevadas taxas de deposicao dos filmes de silicio depositados sobre plastico foram obtidas a baixa temperatura do substrato (150ºC) por rf-PECVD. A influencia de diferentes parametros de deposicao sobre as propriedades e taxa de deposicao dos filmes resultantes foram estudados e correlacionados. Celulas solares de filmes finos de silicio amorfo e microcristalino foram desenvolvidas a baixas temperaturas sobre plasticos. Eficiencias de 5 - 6.5% foram alcancadas para as celulas amorfas e 7.5% para as celulas microcristalinas. Efeitos de aprisionamento da luz foram estudados atraves da texturizacao por ablacao laser de substratos de plastico e corrosao umida de TCO sobre plastico. Filmes finos de silicio microcristalino, depositados por HW-CVD, com fator piezoresistivo de -32.2, foram usados para fabricar sensores de deformacao em uma membrana plastica muito fina (15 μm). Estruturas de teste em textil e a miniaturizacao dos sensores piezoresistivos depositados sobre substratos flexiveis de poliimida foram abordados.

  14. A Solar Radiation Parameterization for Atmospheric Studies. Volume 15

    Science.gov (United States)

    Chou, Ming-Dah; Suarez, Max J. (Editor)

    1999-01-01

    The solar radiation parameterization (CLIRAD-SW) developed at the Goddard Climate and Radiation Branch for application to atmospheric models are described. It includes the absorption by water vapor, O3, O2, CO2, clouds, and aerosols and the scattering by clouds, aerosols, and gases. Depending upon the nature of absorption, different approaches are applied to different absorbers. In the ultraviolet and visible regions, the spectrum is divided into 8 bands, and single O3 absorption coefficient and Rayleigh scattering coefficient are used for each band. In the infrared, the spectrum is divided into 3 bands, and the k-distribution method is applied for water vapor absorption. The flux reduction due to O2 is derived from a simple function, while the flux reduction due to CO2 is derived from precomputed tables. Cloud single-scattering properties are parameterized, separately for liquid drops and ice, as functions of water amount and effective particle size. A maximum-random approximation is adopted for the overlapping of clouds at different heights. Fluxes are computed using the Delta-Eddington approximation.

  15. Effects of increased solar ultraviolet radiation on terrestrial plants

    International Nuclear Information System (INIS)

    Caldwell, M.M.; Teramura, A.H.; Tevini, M.; Bornman, J.F.; Björn, L.O.; Kulandaivelu, G.

    1995-01-01

    Physiological and developmental processes of plants are affected by UV-B radiation, even by the amount of UV-B in present-day sunlight. Plants also have several mechanisms to ameliorate or repair these effects and may acclimate to a certain extent to increased levels of UV-B. Nevertheless, plant growth can be directly affected by UV-B radiation. Response to UV-B also varies considerably among species and also cultivars of the same species. In agriculture, this may necessitate using more UV-B-tolerant cultivars and breeding new ones. In forests and grasslands, this will likely result in changes in species composition; therefore there are implications for the biodiversity in different ecosystems. Indirect changes caused by UV-B-such as changes in plant form, biomass allocation to parts of the plant, timing of developmental phases and secondary metabolism-may be equally, or sometimes more important than damaging effects of UV-B. These changes can have important implications for plant competitive balance, herbivory, plant pathogens, and biogeochemical cycles. These ecosystem-level effects can be anticipated, but not easily predicted or evaluated. Research at the ecosystem level for solar UV-B is barely beginning. Other factors, including those involved in climate change such as increasing CO2, also interact with UV-B. Such reactions are not easily predicted, but are of obvious importance in both agriculture and in nonagricultural ecosystems

  16. SERI Solar Radiation Resource Assessment Project: Fiscal Year 1990 Annual Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Riordan, C; Maxwell, E; Stoffel, T; Rymes, M; Wilcox, S

    1991-07-01

    The purpose of the Solar Radiation Resource Project is to help meet the needs of the public, government, industry, and utilities for solar radiation data, models, and assessments as required to develop, design, deploy, and operate solar energy conversion systems. The project scientists produce information on the spatial (geographic), temporal (hourly, daily, and seasonal), and spectral (wavelength distribution) variability of solar radiation at different locations in the United States. Resources committed to the project in FY 1990 supported about four staff members, including part-time administrative support. With these resources, the staff must concentrate on solar radiation resource assessment in the United States; funds do not allow for significant efforts to respond to a common need for improved worldwide data. 34 refs., 21 figs., 6 tabs.

  17. Solar Radiation Measurement Using Raspberry Pi and Its Modelling Using Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Priya Selvanathan Shanmuga

    2016-01-01

    Full Text Available The advent of solar energy as the best alternative to traditional energy sources has led to an extensive study on the measurement and prediction of solar radiation. Devices such as pyranometer, pyrrheliometer, global UV radiometer are used for the measurement of solar radiation. The solar radiation measuring instruments available at Innovation Center, MIT Manipal were integrated with a Raspberry Pi to allow remote access to the data through the university Local Area Network. The connections of the data loggers and the Raspberry Pi were enclosed in a plastic box to prevent damage from the rainfall and humidity in Manipal. The solar radiation data was used to validate an Artificial Neural Network model which was developed using various meterological data from 2011-2015.

  18. An overview of global solar radiation measurements in Ghardaia area, south Algeria

    Energy Technology Data Exchange (ETDEWEB)

    Gairaa, Kacem; Bakelli, Yahia [Applied Research Unit for Renewables Energies, Ouargla Road, Ghardaia (Algeria)

    2011-07-01

    This paper presents an overview of actual solar radiation data measurements in Ghardaia site (32.360 N, 3.810 W, 450 m above MSL). Global solar radiation and surface temperatures were measured and analyzed for one complete year from 1 January-31December 2005. The data thus recorded are compared with corresponding data of the 22-year average of NASA's surface meteorology and solar energy-model. Hourly, daily and monthly solar radiation was made from five-minute recorded by EKO Pyranometer. The highest measured daily and monthly mean solar radiation was found to be 369 and 326 (W/m2), and the highest five minute averaged solar radiation values up to 1268 (W/m2) were observed in the summer season from May to September, and the yearly average daily energy input was 21.83 (MJ/m2/day). Besides the global solar radiation, the daily and monthly average temperature variations are discussed. The collected data indicate that Ghardaia has a strong potential for solar energy applications.

  19. Solar Electromagnetic Radiation Study for Solar Cycle 22: Solar Ultraviolet Irradiance, 120 to 300 NM: Report of Working Groups 2 and 3 of SOLERS 22

    Science.gov (United States)

    Rottman, G. J.; Cebula, R. P.; Gillotay, D.; Simon, P. A.

    1996-01-01

    This report summarizes the activities of Working Group 2 and Working Group 3 of the SOLax Electromagnetic Radiation Study for Solar Cycle 22 (SOLERS22) Program. The international (SOLERS22) is Project 1.2 of the Solar-Terrestrial Energy Program (STEP) sponsored by SCOSTEP, a committee of the International Council of Scientific Unions). SOLERS22 is comprised of five Working Groups, each concentrating on a specific wave-length range: WG-1 - visible and infrared, WG-2 - mid-ultraviolet (200 solar irradiance values in the specified wavelength ranges, 2) consider the evolving solar structures as the cause of temporal variations, and 3) understand the underlying physical processes driving these changes.

  20. Total dose radiation effects of pressure sensors fabricated on uni-bond-SOI materials

    International Nuclear Information System (INIS)

    Zhu Shiyang; Huang Yiping; Wang Jin; Li Anzhen; Shen Shaoqun; Bao Minhang

    2001-01-01

    Piezoresistive pressure sensors with a twin-island structure were successfully fabricated using high quality Uni-bond-SOI (On Insulator) materials. Since the piezoresistors were structured by the single crystalline silicon overlayer of the SOI wafer and were totally isolated by the buried SiO 2 , the sensors are radiation-hard. The sensitivity and the linearity of the pressure sensors keep their original values after being irradiated by 60 Co γ-rays up to 2.3 x 10 4 Gy(H 2 O). However, the offset voltage of the sensor has a slight drift, increasing with the radiation dose. The absolute value of the offset voltage deviation depends on the pressure sensor itself. For comparison, corresponding polysilicon pressure sensors were fabricated using the similar process and irradiated at the same condition

  1. Characterization of Tin/Ethylene Glycol Solar Nanofluids Synthesized by Femtosecond Laser Radiation.

    Science.gov (United States)

    Torres-Mendieta, Rafael; Mondragón, Rosa; Puerto-Belda, Verónica; Mendoza-Yero, Omel; Lancis, Jesús; Juliá, J Enrique; Mínguez-Vega, Gladys

    2017-05-05

    Solar energy is available over wide geographical areas and its harnessing is becoming an essential tool to satisfy the ever-increasing demand for energy with minimal environmental impact. Solar nanofluids are a novel solar receiver concept for efficient harvesting of solar radiation based on volumetric absorption of directly irradiated nanoparticles in a heat transfer fluid. Herein, the fabrication of a solar nanofluid by pulsed laser ablation in liquids was explored. This study was conducted with the ablation of bulk tin immersed in ethylene glycol with a femtosecond laser. Laser irradiation promotes the formation of tin nanoparticles that are collected in the ethylene glycol as colloids, creating the solar nanofluid. The ability to trap incoming electromagnetic radiation, thermal conductivity, and the stability of the solar nanofluid in comparison with conventional synthesis methods is enhanced. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Design of a Solar Tracking System Using the Brightest Region in the Sky Image Sensor.

    Science.gov (United States)

    Wei, Ching-Chuan; Song, Yu-Chang; Chang, Chia-Chi; Lin, Chuan-Bi

    2016-11-25

    Solar energy is certainly an energy source worth exploring and utilizing because of the environmental protection it offers. However, the conversion efficiency of solar energy is still low. If the photovoltaic panel perpendicularly tracks the sun, the solar energy conversion efficiency will be improved. In this article, we propose an innovative method to track the sun using an image sensor. In our method, it is logical to assume the points of the brightest region in the sky image representing the location of the sun. Then, the center of the brightest region is assumed to be the solar-center, and is mathematically calculated using an embedded processor (Raspberry Pi). Finally, the location information on the sun center is sent to the embedded processor to control two servo motors that are capable of moving both horizontally and vertically to track the sun. In comparison with the existing sun tracking methods using image sensors, such as the Hough transform method, our method based on the brightest region in the sky image remains accurate under conditions such as a sunny day and building shelter. The practical sun tracking system using our method was implemented and tested. The results reveal that the system successfully captured the real sun center in most weather conditions, and the servo motor system was able to direct the photovoltaic panel perpendicularly to the sun center. In addition, our system can be easily and practically integrated, and can operate in real-time.

  3. Design of a Solar Tracking System Using the Brightest Region in the Sky Image Sensor

    Directory of Open Access Journals (Sweden)

    Ching-Chuan Wei

    2016-11-01

    Full Text Available Solar energy is certainly an energy source worth exploring and utilizing because of the environmental protection it offers. However, the conversion efficiency of solar energy is still low. If the photovoltaic panel perpendicularly tracks the sun, the solar energy conversion efficiency will be improved. In this article, we propose an innovative method to track the sun using an image sensor. In our method, it is logical to assume the points of the brightest region in the sky image representing the location of the sun. Then, the center of the brightest region is assumed to be the solar-center, and is mathematically calculated using an embedded processor (Raspberry Pi. Finally, the location information on the sun center is sent to the embedded processor to control two servo motors that are capable of moving both horizontally and vertically to track the sun. In comparison with the existing sun tracking methods using image sensors, such as the Hough transform method, our method based on the brightest region in the sky image remains accurate under conditions such as a sunny day and building shelter. The practical sun tracking system using our method was implemented and tested. The results reveal that the system successfully captured the real sun center in most weather conditions, and the servo motor system was able to direct the photovoltaic panel perpendicularly to the sun center. In addition, our system can be easily and practically integrated, and can operate in real-time.

  4. Estimating the solar radiation environment on the soil surface between rows using crop canopy architectural models

    International Nuclear Information System (INIS)

    Yuge, K.; Haraguchi, T.; Nakano, Y.; Kuroda, M.; Funakoshi, T.

    2002-01-01

    The objective of this study is quantification of the solar radiation in the farmland located in the hilly and mountainous areas, considering the effect of the shelter adjacent to the field, such as the forest (This effect is called as the edge-effect in this study.). To evaluate the edge-effect on the solar radiation environment in the farmland, solar radiations are measured at the center and edge of the study site adjacent to the forest. The simulation model is composed, coupling with the fish-eye projection method and procedure for the separating direct and diffuse solar radiations. Using this model, the diurnal solar radiations are simulated at the center and edge of the study site. The simulation result showed good agreement with the observation. The spatial distribution of the solar radiation in an observational field is quantified by this method, considering the edge-effect. The simulation result indicated that the solar radiation environment on the field surface is affected by the shelter adjacent to the field and the field direction. (author)

  5. A Fiber Bragg Grating—Bimetal Temperature Sensor for Solar Panel Inverters

    Directory of Open Access Journals (Sweden)

    Mohd Afiq Ismail

    2011-09-01

    Full Text Available This paper reports the design, characterization and implementation of a Fiber Bragg Grating (FBG-based temperature sensor for an Insulted-Gate Bipolar Transistor (IGBT in a solar panel inverter. The FBG is bonded to the higher Coefficient of Thermal Expansion (CTE side of a bimetallic strip to increase its sensitivity. Characterization results show a linear relationship between increasing temperature and the wavelength shift. It is found that the sensitivity of the sensor can be categorized into three characterization temperature regions between 26 °C and 90 °C. The region from 41 °C to 90 °C shows the highest sensitivity, with a value of 14 pm/°C. A new empirical model that considers both temperature and strain effects has been developed for the sensor. Finally, the FBG-bimetal temperature sensor is placed in a solar panel inverter and results confirm that it can be used for real-time monitoring of the IGBT temperature.

  6. A fiber Bragg grating--bimetal temperature sensor for solar panel inverters.

    Science.gov (United States)

    Ismail, Mohd Afiq; Tamchek, Nizam; Hassan, Muhammad Rosdi Abu; Dambul, Katrina D; Selvaraj, Jeyrai; Rahim, Nasrudin Abd; Sandoghchi, Reza; Adikan, Faisal Rafiq Mahamd

    2011-01-01

    This paper reports the design, characterization and implementation of a fiber Bragg grating (FBG)-based temperature sensor for an insulted-gate Bipolar transistor (IGBT) in a solar panel inverter. The FBG is bonded to the higher coefficient of thermal expansion (CTE) side of a bimetallic strip to increase its sensitivity. Characterization results show a linear relationship between increasing temperature and the wavelength shift. It is found that the sensitivity of the sensor can be categorized into three characterization temperature regions between 26 °C and 90 °C. The region from 41 °C to 90 °C shows the highest sensitivity, with a value of 14 pm/°C. A new empirical model that considers both temperature and strain effects has been developed for the sensor. Finally, the FBG-bimetal temperature sensor is placed in a solar panel inverter and results confirm that it can be used for real-time monitoring of the IGBT temperature.

  7. A Maximum Likelihood Approach to Determine Sensor Radiometric Response Coefficients for NPP VIIRS Reflective Solar Bands

    Science.gov (United States)

    Lei, Ning; Chiang, Kwo-Fu; Oudrari, Hassan; Xiong, Xiaoxiong

    2011-01-01

    Optical sensors aboard Earth orbiting satellites such as the next generation Visible/Infrared Imager/Radiometer Suite (VIIRS) assume that the sensors radiometric response in the Reflective Solar Bands (RSB) is described by a quadratic polynomial, in relating the aperture spectral radiance to the sensor Digital Number (DN) readout. For VIIRS Flight Unit 1, the coefficients are to be determined before launch by an attenuation method, although the linear coefficient will be further determined on-orbit through observing the Solar Diffuser. In determining the quadratic polynomial coefficients by the attenuation method, a Maximum Likelihood approach is applied in carrying out the least-squares procedure. Crucial to the Maximum Likelihood least-squares procedure is the computation of the weight. The weight not only has a contribution from the noise of the sensor s digital count, with an important contribution from digitization error, but also is affected heavily by the mathematical expression used to predict the value of the dependent variable, because both the independent and the dependent variables contain random noise. In addition, model errors have a major impact on the uncertainties of the coefficients. The Maximum Likelihood approach demonstrates the inadequacy of the attenuation method model with a quadratic polynomial for the retrieved spectral radiance. We show that using the inadequate model dramatically increases the uncertainties of the coefficients. We compute the coefficient values and their uncertainties, considering both measurement and model errors.

  8. The use of antenna radiation pattern in node localisation algorithms for wireless sensor networks

    CSIR Research Space (South Africa)

    Mwila, MK

    2014-08-01

    Full Text Available due to the limited accuracy inherent to the current ranging model. These models, however, make the assumption that the antenna radiation pattern is omnidirectional targeted to simplifying the complexity of the algorithms. An increasing number of sensor...

  9. Design of autotrack detecting instrument for solar UV radiation

    Science.gov (United States)

    Xia, Jiangtao; Mao, Xiaoli; Zhao, Jing

    2009-11-01

    In order to autotrack the object and detect the solar UV index, a reliable real-time high-precise instrument is proposed in this paper. This instrument involves two subsystems: the autotrack and detecting modules. The autotrack module consists of four-quadrant photo detector, multi-channel signal processing circuit and precise stepping system. The detecting module designed for dada measurement and acquisition is made up of the ultraviolet sensor UV460 and high precision A/D converter MAX1162. The key component of the entire instrument is ultralow-power microprocessor MSP430 which is used for entire system controlling and data processing. The lower system of autotracking and measurement is communicated with upper PC computer by RS232 module. In the experiment, the tracking precision of two-dimensional motion revolving stage is calibrated to be less than 0.05°. Experimental results indicate that the system designed could realize the precise autotracking and detecting function well, and the measure precision of system has reached the desirable target.

  10. Estimation of global solar radiation by means of sunshine duration

    Energy Technology Data Exchange (ETDEWEB)

    Luis, Mazorra Aguiar; Felipe, Diaz Reyes [Electrical Engineering Dept., Las Palmas de Gran Canaria Univ. (U.L.P.G.C.), Campus Univ. Tafira (Spain); Pilar, Navarro Rivero [Canary Islands Technological Inst. (I.T.C.), Gran Canaria (Spain)

    2008-07-01

    This paper analyses the relationship between global solar irradiation and sunshine duration with different estimation models for the island of Gran Canaria (Spain). These parameters were taken from six measurement stations around the Island, and selected for their reliability and the long period of time they covered. All data used in this paper were handed over by the Canary Islands Technological Institute (I.T.C.). As a first approach, it was decided to study the Angstrom lineal model. In order to improve the knowledge on solar resources, a Typical Meteorological Year (TMY) was created from all daily data. TMY shows differences between southern and northern locations, where Trade Winds generate clouds during the summer months. TMY resumes a data bank much longer than a year in duration, generating the characteristics for a year series of each location, for both irradiation and sunshine duration. To create the TMY, weighted means have been used to smooth high or low values. At first, Angstrom lineal model has been used to estimate solar global irradiation from sunshine duration values, using TMY. But the lineal model didn't reproduce satisfactory results when used to obtain global solar radiation from all daily sunshine duration data. For this reason, different models based in both parameters were used. The parameters estimation of this model was achieved both from TMY daily and monthly series and from all daily data for every location. Because of the weather stability all over the year in the Island, most of the daily data are concentrated in a close range, occasioning a deviation in the lineal equations. To avoid this deviation it was proposed to consider a limit condition data, taking into account values out of the main cloud of data. Additionally, different models were proposed (quadratic, cubic, logarithmic and exponential) to make a regression from all daily data. The best results were obtained with the exponential model proposed in this paper. The

  11. Test and Evaluation of Fiber Optic Sensors for High-Radiation Space Nuclear Power Applications

    International Nuclear Information System (INIS)

    Klemer, Daniel; Fielder, Robert S.; Stinson-Bagby, Kelly L.

    2004-01-01

    Fiber optic sensors can be used to measure a number of parameters, including temperature, strain, pressure and flow, for instrumentation and control of space nuclear power systems. In the past, this technology has often been rejected for use in such a high-radiation environment based on early experiments that revealed a number of degradation phenomena, including radiation-induced fiber attenuation, or 'graying', and Fiber Bragg Grating (FBG) fading and wavelength shift. However, this paper reports the results of recent experimental testing that demonstrates readability of fiber optic sensors to extremely high levels of neutron and gamma radiation. Both distributed Fiber Bragg Grating (FBG) sensors and single-point Extrinsic Fabry Perot Interferometer (EFPI) sensors were continuously monitored over a 2-month period, during which they were exposed to combined neutron and gamma radiation in both in-core and ex-core positions within a nuclear reactor. Total exposure reached approximately 2 x 10 19 cm -2 fast neutron (E > 1 MeV) fluence and 8.7 x 10 8 Gy gamma for in-core sensors. FBG sensors were interrogated using a standard Luna Innovations FBG measurement system, which is based on optical frequency-domain reflectometer (OFDR) technology. Approximately 74% of the 19 FBG sensors located at the core centerline in the in-core position exhibited sufficient signal-to-noise ratio (SNR) to remain readable even after receiving the maximum dose. EFPI sensors were spectrally interrogated using a broadband probe source operating in the 830 nm wavelength region. While these single-point sensors failed early in the test, important additional fiber spectral transmission data was collected, which indicates that interrogation of EFPI sensors in alternate wavelength regions may allow significant improvement in sensor longevity for operation in high-radiation environments. This work was funded through a Small Business Innovative Research (SBIR) contract with the Nasa Glenn Research

  12. Advancing Solar Irradiance Measurement for Climate-Related Studies: Accurate Constraint on Direct Aerosol Radiative Effect (DARE)

    Science.gov (United States)

    Tsay, Si-Chee; Ji, Q. Jack

    2011-01-01

    Earth's climate is driven primarily by solar radiation. As summarized in various IPCC reports, the global average of radiative forcing for different agents and mechanisms, such as aerosols or CO2 doubling, is in the range of a few W/sq m. However, when solar irradiance is measured by broadband radiometers, such as the fleet of Eppley Precision Solar Pyranometers (PSP) and equivalent instrumentation employed worldwide, the measurement uncertainty is larger than 2% (e.g., WMO specification of pyranometer, 2008). Thus, out of the approx. 184 W/sq m (approx.263 W/sq m if cloud-free) surface solar insolation (Trenberth et al. 2009), the measurement uncertainty is greater than +/-3.6 W/sq m, overwhelming the climate change signals. To discern these signals, less than a 1 % measurement uncertainty is required and is currently achievable only by means of a newly developed methodology employing a modified PSP-like pyranometer and an updated calibration equation to account for its thermal effects (li and Tsay, 2010). In this talk, we will show that some auxiliary measurements, such as those from a collocated pyrgeometer or air temperature sensors, can help correct historical datasets. Additionally, we will also demonstrate that a pyrheliometer is not free of the thermal effect; therefore, comparing to a high cost yet still not thermal-effect-free "direct + diffuse" approach in measuring surface solar irradiance, our new method is more economical, and more likely to be suitable for correcting a wide variety of historical datasets. Modeling simulations will be presented that a corrected solar irradiance measurement has a significant impact on aerosol forcing, and thus plays an important role in climate studies.

  13. A three-dimensional model of solar radiation transfer in a non-uniform plant canopy

    Science.gov (United States)

    Levashova, N. T.; Mukhartova, Yu V.

    2018-01-01

    A three-dimensional (3D) model of solar radiation transfer in a non-uniform plant canopy was developed. It is based on radiative transfer equations and a so-called turbid medium assumption. The model takes into account the multiple scattering contributions of plant elements in radiation fluxes. These enable more accurate descriptions of plant canopy reflectance and transmission in different spectral bands. The model was applied to assess the effects of plant canopy heterogeneity on solar radiation transmission and to quantify the difference in a radiation transfer between photosynthetically active radiation PAR (=0.39-0.72 μm) and near infrared solar radiation NIR (Δλ = 0.72-3.00 μm). Comparisons of the radiative transfer fluxes simulated by the 3D model within a plant canopy consisted of sparsely planted fruit trees (plant area index, PAI - 0.96 m2 m-2) with radiation fluxes simulated by a one-dimensional (1D) approach, assumed horizontal homogeneity of plant and leaf area distributions, showed that, for sunny weather conditions with a high solar elevation angle, an application of a simplified 1D approach can result in an underestimation of transmitted solar radiation by about 22% for PAR, and by about 26% for NIR.

  14. Numerical simulation of heat transfer process in solar enhanced natural draft dry cooling tower with radiation model

    International Nuclear Information System (INIS)

    Wang, Qiuhuan; Zhu, Jialing; Lu, Xinli

    2017-01-01

    Graphical abstract: A 3-D numerical model integrated with a discrete ordinate (DO) solar radiation model (considering solar radiation effect in the room of solar collector) was developed to investigate the influence of solar radiation intensity and ambient pressure on the efficiency and thermal characteristics of the SENDDCT. Our study shows that introducing such a radiation model can more accurately simulate the heat transfer process in the SENDDCT. Calculation results indicate that previous simulations overestimated solar energy obtained by the solar collector and underestimated the heat loss. The cooling performance is improved when the solar radiation intensity or ambient pressure is high. Air temperature and velocity increase with the increase of solar radiation intensity. But ambient pressure has inverse effects on the changes of air temperature and velocity. Under a condition that the solar load increases but the ambient pressure decreases, the increased rate of heat transferred in the heat exchanger is not obvious. Thus the performance of the SENDDCT not only depends on the solar radiation intensity but also depends on the ambient pressure. - Highlights: • A radiation model has been introduced to accurately simulate heat transfer process. • Heat transfer rate would be overestimated if the radiation model was not introduced. • The heat transfer rate is approximately proportional to solar radiation intensity. • The higher the solar radiation or ambient pressure, the better SENDDCT performance. - Abstract: Solar enhanced natural draft dry cooling tower (SENDDCT) is more efficient than natural draft dry cooling tower by utilizing solar radiation in arid region. A three-dimensional numerical model considering solar radiation effect was developed to investigate the influence of solar radiation intensity and ambient pressure on the efficiency and thermal characteristics of SENDDCT. The numerical simulation outcomes reveal that a model with consideration of

  15. Developing a new solar radiation estimation model based on Buckingham theorem

    Science.gov (United States)

    Ekici, Can; Teke, Ismail

    2018-06-01

    While the value of solar radiation can be expressed physically in the days without clouds, this expression becomes difficult in cloudy and complicated weather conditions. In addition, solar radiation measurements are often not taken in developing countries. In such cases, solar radiation estimation models are used. Solar radiation prediction models estimate solar radiation using other measured meteorological parameters those are available in the stations. In this study, a solar radiation estimation model was obtained using Buckingham theorem. This theory has been shown to be useful in predicting solar radiation. In this study, Buckingham theorem is used to express the solar radiation by derivation of dimensionless pi parameters. This derived model is compared with temperature based models in the literature. MPE, RMSE, MBE and NSE error analysis methods are used in this comparison. Allen, Hargreaves, Chen and Bristow-Campbell models in the literature are used for comparison. North Dakota's meteorological data were used to compare the models. Error analysis were applied through the comparisons between the models in the literature and the model that is derived in the study. These comparisons were made using data obtained from North Dakota's agricultural climate network. In these applications, the model obtained within the scope of the study gives better results. Especially, in terms of short-term performance, it has been found that the obtained model gives satisfactory results. It has been seen that this model gives better accuracy in comparison with other models. It is possible in RMSE analysis results. Buckingham theorem was found useful in estimating solar radiation. In terms of long term performances and percentage errors, the model has given good results.

  16. Solar radiation during rewarming from torpor in elephant shrews: supplementation or substitution of endogenous heat production?

    Science.gov (United States)

    Thompson, Michelle L; Mzilikazi, Nomakwezi; Bennett, Nigel C; McKechnie, Andrew E

    2015-01-01

    Many small mammals bask in the sun during rewarming from heterothermy, but the implications of this behaviour for their energy balance remain little understood. Specifically, it remains unclear whether solar radiation supplements endogenous metabolic thermogenesis (i.e., rewarming occurs through the additive effects of internally-produced and external heat), or whether solar radiation reduces the energy required to rewarm by substituting (i.e, replacing) metabolic heat production. To address this question, we examined patterns of torpor and rewarming rates in eastern rock elephant shrews (Elephantulus myurus) housed in outdoor cages with access to either natural levels of solar radiation or levels that were experimentally reduced by means of shade cloth. We also tested whether acclimation to solar radiation availability was manifested via phenotypic flexibility in basal metabolic rate (BMR), non-shivering thermogenesis (NST) capacity and/or summit metabolism (Msum). Rewarming rates varied significantly among treatments, with elephant shrews experiencing natural solar radiation levels rewarming faster than conspecifics experiencing solar radiation levels equivalent to approximately 20% or 40% of natural levels. BMR differed significantly between individuals experiencing natural levels of solar radiation and conspecifics experiencing approximately 20% of natural levels, but no between-treatment difference was evident for NST capacity or Msum. The positive relationship between solar radiation availability and rewarming rate, together with the absence of acclimation in maximum non-shivering and total heat production capacities, suggests that under the conditions of this study solar radiation supplemented rather than substituted metabolic thermogenesis as a source of heat during rewarming from heterothermy.

  17. The solar ultraviolet B radiation protection provided by shading devices with regard to its diffuse component.

    Science.gov (United States)

    Kudish, Avraham I; Harari, Marco; Evseev, Efim G

    2011-10-01

    The composition of the incident solar global ultraviolet B (UVB) radiation with regard to its beam and diffuse radiation fractions is highly relevant with regard to outdoor sun protection. This is especially true with respect to sun protection during leisure-time outdoor sun exposure at the shore and pools, where people tend to escape the sun under shade trees or different types of shading devices, e.g., umbrellas, overhangs, etc., believing they offer protection from the erythemal solar radiation. The degree of sun protection offered by such devices is directly related to the composition of the solar global UVB radiation, i.e., its beam and diffuse fractions. The composition of the incident solar global UVB radiation can be determined by measuring the global UVB (using Solar Light Co. Inc., Model 501A UV-Biometer) and either of its components. The beam component of the UVB radiation was determined by measuring the normal incidence beam radiation using a prototype, tracking instrument consisting of a Solar Light Co. Inc. Model 501A UV-Biometer mounted on an Eppley Solar Tracker Model St-1. The horizontal beam component of the global UVB radiation was calculated from the measured normal incidence using a simple geometric correlation and the diffuse component is determined as the difference between global and horizontal beam radiations. Horizontal and vertical surfaces positioned under a horizontal overhang/sunshade or an umbrella are not fully protected from exposure to solar global UVB radiation. They can receive a significant fraction of the UVB radiation, depending on their location beneath the shading device, the umbrella radius and the albedo (reflectance) of the surrounding ground surface in the case of a vertical surface. Shading devices such as an umbrella or horizontal overhang/shade provide relief from the solar global radiation and do block the solar global UVB radiation to some extent; nevertheless, a significant fraction of the solar global UVB

  18. Estimation of solar radiation over Cambodia from long-term satellite data

    Energy Technology Data Exchange (ETDEWEB)

    Janjai, S.; Pankaew, P.; Laksanaboonsong, J. [Solar Energy Research Laboratory, Department of Physics, Faculty of Science, Silpakorn University, Nakhon Pathom 73000 (Thailand); Kitichantaropas, P. [Department of Alternative Energy Development and Efficiency, Ministry of Energy, 17 Rama 1 Road, Patumwan, Bangkok 10330 (Thailand)

    2011-04-15

    In this work, monthly average daily global solar irradiation over Cambodia was estimated from a long-term satellite data. A 14-year period (1995-2008) of visible channel data from GMS5, GOES9 and MTSAT-1R satellites were used to provide earth-atmospheric reflectivity. A satellite-based solar radiation model developed for a tropical environment was used to estimate surface solar radiation. The model relates the satellite-derived earth-atmospheric reflectivity to absorption and scattering coefficients of various atmospheric constituents. The absorption of solar radiation due to water vapour was calculated from precipitable water derived from ambient relative humidity and temperature. Ozone data from the TOMS and OMI satellite data were employed to compute the solar radiation absorption by ozone. The depletion of radiation due to aerosols was estimated from the visibility data. Five new solar radiation measuring stations were established at Cambodian cities, namely Siem Reap (13.87 N, 103.85 E), Kompong Thom (12.68 N, 104.88 E), Phnom Penh (11.55 N, 104.83 E), Sihanouke Ville (10.67 N, 103.63 E) and Kampot (10.70 N, 104.28 E). Global solar radiation measured at these stations was used to validate the model. The validation was also carried out by using solar radiation measured at four Thai meteorological stations. These stations are situated near the Cambodian border. Monthly average daily global irradiation from these stations was compared with that calculated from the model. The measured and calculated irradiation is in good agreement, with the root mean square difference of 6.3%, with respect to the mean values. After the validation, the model was used to calculate monthly average daily global solar irradiation over Cambodia. Based on this satellite-derived irradiation, solar radiation maps for Cambodia were generated. These maps show that solar radiation climate of this country is strongly influenced by the monsoons. A solar radiation database was also generated

  19. Atmospheric turbidity parameters affecting the incident solar solar radiation for two different areas in (Eg))

    International Nuclear Information System (INIS)

    Tadros, M.T.Y.; Mosalam, M.A.; El-metwally, M.

    1999-01-01

    Atmospheric turbidity parameters such as Linke turbidity (L-0) and true Angstrom parameters (Bita o , Alpha 0 ) have been determined from the measurements of direct solar radiation for entire spectrum and for specified spectral bands during one year starting from june 1992 to may 1993. Comparison between the industrial area in Helwan (south Cairo) with that of the agricultural area in Mansoura, in (Eg), was done. Analysis of data revealed that the atmospheric turbidity parameters (L Beta) in Helwan is higher than that in Mansoura, except for hot wet months. The increase of L in Mansoura, in summer, is due to the increase of water vapor content. The wavelength exponent Alpha shows that the size the size of particles in Helwan is larger than that in Mansoura

  20. Investigation of variations and trends in solar radiation in Klang Valley Region, Malaysia

    International Nuclear Information System (INIS)

    Mohamed Elnour Yassen, Jamaluddin Mohd Jahi

    2006-01-01

    The objective of this study is to investigate variations and trends in the global solar radiation in Klang Valley region. The least square method was used for the trend analysis. Since the available time series covers 27 years, linear regression was preferred for the trend analysis. The linear trend is used mainly to test the change in solar radiation and to set limits on the rate of change. Trend line and values and significance levels of the slopes have been found. The seasonal and the annual average values were computed from the monthly average radiation data. The seasonal and annual average solar radiation values were designated as dependent variables, and thus, were fitted linearly for season and annual means for each station. The results showed that the mean of maximum incoming global radiation in Sepember with a value of 21.1 MJ m-2 at Petaling Jaya, while the mean minimum in November and December with values of 10.7 and 10.9 MJ m-2 at Petaling Jaya. The low amounts of solar radiation received in November and December are due to greater cloudiness during the period coinciding with the northeast monsoon season. On rainy days, very little global solar radiation received in November and December are due to greater cloudiness during the period coinciding with the northeast monsoon season. On rainy days, very little global solar radiation is received. The distribution of the seasonal mean values of solar radiation exhibits a high symmetry. Inter-monsoon seasons (April-May) and (October-November) show a similar behavior, just like the northeast monsoon season. The overall average rate of change in global solar radiation during 1975-2002 and 1977-2000 is represented by the slope of the linear regression was small (-0.126 and -0.314 MJ m-2 per year for Subang Airport and Petaling Jaya respectively)