Hydrophone area-averaging correction factors in nonlinearly generated ultrasonic beams

International Nuclear Information System (INIS)

Cooling, M P; Humphrey, V F; Wilkens, V

2011-01-01

The nonlinear propagation of an ultrasonic wave can be used to produce a wavefield rich in higher frequency components that is ideally suited to the calibration, or inter-calibration, of hydrophones. These techniques usually use a tone-burst signal, limiting the measurements to harmonics of the fundamental calibration frequency. Alternatively, using a short pulse enables calibration at a continuous spectrum of frequencies. Such a technique is used at PTB in conjunction with an optical measurement technique to calibrate devices. Experimental findings indicate that the area-averaging correction factor for a hydrophone in such a field demonstrates a complex behaviour, most notably varying periodically between frequencies that are harmonics of the centre frequency of the original pulse and frequencies that lie midway between these harmonics. The beam characteristics of such nonlinearly generated fields have been investigated using a finite difference solution to the nonlinear Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation for a focused field. The simulation results are used to calculate the hydrophone area-averaging correction factors for 0.2 mm and 0.5 mm devices. The results clearly demonstrate a number of significant features observed in the experimental investigations, including the variation with frequency, drive level and hydrophone element size. An explanation for these effects is also proposed.

Hydrophone area-averaging correction factors in nonlinearly generated ultrasonic beams

Science.gov (United States)

Cooling, M. P.; Humphrey, V. F.; Wilkens, V.

2011-02-01

The nonlinear propagation of an ultrasonic wave can be used to produce a wavefield rich in higher frequency components that is ideally suited to the calibration, or inter-calibration, of hydrophones. These techniques usually use a tone-burst signal, limiting the measurements to harmonics of the fundamental calibration frequency. Alternatively, using a short pulse enables calibration at a continuous spectrum of frequencies. Such a technique is used at PTB in conjunction with an optical measurement technique to calibrate devices. Experimental findings indicate that the area-averaging correction factor for a hydrophone in such a field demonstrates a complex behaviour, most notably varying periodically between frequencies that are harmonics of the centre frequency of the original pulse and frequencies that lie midway between these harmonics. The beam characteristics of such nonlinearly generated fields have been investigated using a finite difference solution to the nonlinear Khokhlov-Zabolotskaya-Kuznetsov (KZK) equation for a focused field. The simulation results are used to calculate the hydrophone area-averaging correction factors for 0.2 mm and 0.5 mm devices. The results clearly demonstrate a number of significant features observed in the experimental investigations, including the variation with frequency, drive level and hydrophone element size. An explanation for these effects is also proposed.

Investigation on the average serum E2 level and menopausal age in healthy women in Wuhan area

International Nuclear Information System (INIS)

Chen Huilin; Lan Jian; Zhang Yangyang; Li Fei; Zhang Yuanji

2008-01-01

Objective: To investigate the average serum E 2 level and menopausal age of healthy women in Wuhan area and assess the appropriateness of hormone replacement therapy in these women. Methods: Serum E 2 levels were measured with RIA in 2020 healthy women (26-75 yr old) in Wuhan area. Results: (1) Serum E 2 levels reached peak in 31-35yr group, significantly dropped in 46-50yr group and reached menopausal level in 51-55 yr group. (2) The average menopausal age in Wuhan area was rather early-48.08yr. Conclusion: The average menopausal age in Wuhan area was 2.3yr earlier than the nationwide 1989 screening result, which should be a concern for the maternity health workers. (authors)

Adaptive neuro-fuzzy based inferential sensor model for estimating the average air temperature in space heating systems

Energy Technology Data Exchange (ETDEWEB)

Jassar, S.; Zhao, L. [Department of Electrical and Computer Engineering, Ryerson University, 350 Victoria Street, Toronto, ON (Canada); Liao, Z. [Department of Architectural Science, Ryerson University (Canada)

2009-08-15

The heating systems are conventionally controlled by open-loop control systems because of the absence of practical methods for estimating average air temperature in the built environment. An inferential sensor model, based on adaptive neuro-fuzzy inference system modeling, for estimating the average air temperature in multi-zone space heating systems is developed. This modeling technique has the advantage of expert knowledge of fuzzy inference systems (FISs) and learning capability of artificial neural networks (ANNs). A hybrid learning algorithm, which combines the least-square method and the back-propagation algorithm, is used to identify the parameters of the network. This paper describes an adaptive network based inferential sensor that can be used to design closed-loop control for space heating systems. The research aims to improve the overall performance of heating systems, in terms of energy efficiency and thermal comfort. The average air temperature results estimated by using the developed model are strongly in agreement with the experimental results. (author)

Using Bayesian Model Averaging (BMA) to calibrate probabilistic surface temperature forecasts over Iran

Energy Technology Data Exchange (ETDEWEB)

Soltanzadeh, I. [Tehran Univ. (Iran, Islamic Republic of). Inst. of Geophysics; Azadi, M.; Vakili, G.A. [Atmospheric Science and Meteorological Research Center (ASMERC), Teheran (Iran, Islamic Republic of)

2011-07-01

Using Bayesian Model Averaging (BMA), an attempt was made to obtain calibrated probabilistic numerical forecasts of 2-m temperature over Iran. The ensemble employs three limited area models (WRF, MM5 and HRM), with WRF used with five different configurations. Initial and boundary conditions for MM5 and WRF are obtained from the National Centers for Environmental Prediction (NCEP) Global Forecast System (GFS) and for HRM the initial and boundary conditions come from analysis of Global Model Europe (GME) of the German Weather Service. The resulting ensemble of seven members was run for a period of 6 months (from December 2008 to May 2009) over Iran. The 48-h raw ensemble outputs were calibrated using BMA technique for 120 days using a 40 days training sample of forecasts and relative verification data. The calibrated probabilistic forecasts were assessed using rank histogram and attribute diagrams. Results showed that application of BMA improved the reliability of the raw ensemble. Using the weighted ensemble mean forecast as a deterministic forecast it was found that the deterministic-style BMA forecasts performed usually better than the best member's deterministic forecast. (orig.)

Using Bayesian Model Averaging (BMA to calibrate probabilistic surface temperature forecasts over Iran

Directory of Open Access Journals (Sweden)

I. Soltanzadeh

2011-07-01

Full Text Available Using Bayesian Model Averaging (BMA, an attempt was made to obtain calibrated probabilistic numerical forecasts of 2-m temperature over Iran. The ensemble employs three limited area models (WRF, MM5 and HRM, with WRF used with five different configurations. Initial and boundary conditions for MM5 and WRF are obtained from the National Centers for Environmental Prediction (NCEP Global Forecast System (GFS and for HRM the initial and boundary conditions come from analysis of Global Model Europe (GME of the German Weather Service. The resulting ensemble of seven members was run for a period of 6 months (from December 2008 to May 2009 over Iran. The 48-h raw ensemble outputs were calibrated using BMA technique for 120 days using a 40 days training sample of forecasts and relative verification data. The calibrated probabilistic forecasts were assessed using rank histogram and attribute diagrams. Results showed that application of BMA improved the reliability of the raw ensemble. Using the weighted ensemble mean forecast as a deterministic forecast it was found that the deterministic-style BMA forecasts performed usually better than the best member's deterministic forecast.

Associations between air temperature and cardio-respiratory mortality in the urban area of Beijing, China: a time-series analysis.

Science.gov (United States)

Liu, Liqun; Breitner, Susanne; Pan, Xiaochuan; Franck, Ulrich; Leitte, Arne Marian; Wiedensohler, Alfred; von Klot, Stephanie; Wichmann, H-Erich; Peters, Annette; Schneider, Alexandra

2011-05-25

Associations between air temperature and mortality have been consistently observed in Europe and the United States; however, there is a lack of studies for Asian countries. Our study investigated the association between air temperature and cardio-respiratory mortality in the urban area of Beijing, China. Death counts for cardiovascular and respiratory diseases for adult residents (≥15 years), meteorological parameters and concentrations of particulate air pollution were obtained from January 2003 to August 2005. The effects of two-day and 15-day average temperatures were estimated by Poisson regression models, controlling for time trend, relative humidity and other confounders if necessary. Effects were explored for warm (April to September) and cold periods (October to March) separately. The lagged effects of daily temperature were investigated by polynomial distributed lag (PDL) models. We observed a J-shaped exposure-response function only for 15-day average temperature and respiratory mortality in the warm period, with 21.3°C as the threshold temperature. All other exposure-response functions could be considered as linear. In the warm period, a 5°C increase of two-day average temperature was associated with a RR of 1.098 (95% confidence interval (95%CI): 1.057-1.140) for cardiovascular and 1.134 (95%CI: 1.050-1.224) for respiratory mortality; a 5°C decrease of 15-day average temperature was associated with a RR of 1.040 (95%CI: 0.990-1.093) for cardiovascular mortality. In the cold period, a 5°C increase of two-day average temperature was associated with a RR of 1.149 (95%CI: 1.078-1.224) for respiratory mortality; a 5°C decrease of 15-day average temperature was associated with a RR of 1.057 (95%CI: 1.022-1.094) for cardiovascular mortality. The effects remained robust after considering particles as additional confounders. Both increases and decreases in air temperature are associated with an increased risk of cardiovascular mortality. The effects of

Associations between air temperature and cardio-respiratory mortality in the urban area of Beijing, China: a time-series analysis

Directory of Open Access Journals (Sweden)

Wiedensohler Alfred

2011-05-01

Full Text Available Abstract Background Associations between air temperature and mortality have been consistently observed in Europe and the United States; however, there is a lack of studies for Asian countries. Our study investigated the association between air temperature and cardio-respiratory mortality in the urban area of Beijing, China. Methods Death counts for cardiovascular and respiratory diseases for adult residents (≥15 years, meteorological parameters and concentrations of particulate air pollution were obtained from January 2003 to August 2005. The effects of two-day and 15-day average temperatures were estimated by Poisson regression models, controlling for time trend, relative humidity and other confounders if necessary. Effects were explored for warm (April to September and cold periods (October to March separately. The lagged effects of daily temperature were investigated by polynomial distributed lag (PDL models. Results We observed a J-shaped exposure-response function only for 15-day average temperature and respiratory mortality in the warm period, with 21.3°C as the threshold temperature. All other exposure-response functions could be considered as linear. In the warm period, a 5°C increase of two-day average temperature was associated with a RR of 1.098 (95% confidence interval (95%CI: 1.057-1.140 for cardiovascular and 1.134 (95%CI: 1.050-1.224 for respiratory mortality; a 5°C decrease of 15-day average temperature was associated with a RR of 1.040 (95%CI: 0.990-1.093 for cardiovascular mortality. In the cold period, a 5°C increase of two-day average temperature was associated with a RR of 1.149 (95%CI: 1.078-1.224 for respiratory mortality; a 5°C decrease of 15-day average temperature was associated with a RR of 1.057 (95%CI: 1.022-1.094 for cardiovascular mortality. The effects remained robust after considering particles as additional confounders. Conclusions Both increases and decreases in air temperature are associated with an

Effect of average diurnal barn airspace temperatures on prediction of their development during the day

Directory of Open Access Journals (Sweden)

Gustav Chládek

2011-01-01

Full Text Available A year-round (i.e. 365 days experiment was performed at the Mendel University Training Farm in Žabčice, Czech Republic (GPS 49°0’51.967”N and 16°36’14.614”E, the altitude 179 m with the aim to quantify the effect of the variation of average diurnal barn airspace temperatures on prediction of their changes during the day. Barn airspace temperatures were monitored daily in one-hour intervals and the recorded values were used for calculations of average diurnal temperatures. These were classified into 7 categories (i.e. below 0 °C; 0.1 to 5 °C; 5.1 to 10 °C; 10.1 to 15 °C; 15.1 to 20 °C; 20.1 to 25 °C and above 25 °C. Regarding this classification system, all differences between temperatures measured at identical hours but within various limits were statistically highly significant. The statistical analysis involved also the calculation of the third degree polynomial regression equations, which enabled to characterise the relationship between the temperature and the hour of measurement within the aforementioned categories of diurnal temperatures. Individual equations were markedly different and ranged from y = − 0.0019x3 + 0.0596x2 − 0.3797x − 1.2169 (for temperatures below 0 °C to y = − 0.0108x3 + 0.3297x2 − 1.9367x + 24.3931 (for temperatures above 25 °C. Correlation coefficients (r and coefficients of determination (R2 of these regression equations were generally very high and ranged from 0.872 to 0.976 and from 0.760 to 0.953, respectively. Regarding high values of both coefficients it can be concluded that the calculated equations enable a good and reliable prediction of the diurnal development of barn airspace temperatures.

Predicting top-of-atmosphere radiance for arbitrary viewing geometries from the visible to thermal infrared: generalization to arbitrary average scene temperatures

Science.gov (United States)

Florio, Christopher J.; Cota, Steve A.; Gaffney, Stephanie K.

2010-08-01

In a companion paper presented at this conference we described how The Aerospace Corporation's Parameterized Image Chain Analysis & Simulation SOftware (PICASSO) may be used in conjunction with a limited number of runs of AFRL's MODTRAN4 radiative transfer code, to quickly predict the top-of-atmosphere (TOA) radiance received in the visible through midwave IR (MWIR) by an earth viewing sensor, for any arbitrary combination of solar and sensor elevation angles. The method is particularly useful for large-scale scene simulations where each pixel could have a unique value of reflectance/emissivity and temperature, making the run-time required for direct prediction via MODTRAN4 prohibitive. In order to be self-consistent, the method described requires an atmospheric model (defined, at a minimum, as a set of vertical temperature, pressure and water vapor profiles) that is consistent with the average scene temperature. MODTRAN4 provides only six model atmospheres, ranging from sub-arctic winter to tropical conditions - too few to cover with sufficient temperature resolution the full range of average scene temperatures that might be of interest. Model atmospheres consistent with intermediate temperature values can be difficult to come by, and in any event, their use would be too cumbersome for use in trade studies involving a large number of average scene temperatures. In this paper we describe and assess a method for predicting TOA radiance for any arbitrary average scene temperature, starting from only a limited number of model atmospheres.

The effect of temperature on the average volume of Barkhausen jump on Q235 carbon steel

Science.gov (United States)

Guo, Lei; Shu, Di; Yin, Liang; Chen, Juan; Qi, Xin

2016-06-01

On the basis of the average volume of Barkhausen jump (AVBJ) vbar generated by irreversible displacement of magnetic domain wall under the effect of the incentive magnetic field on ferromagnetic materials, the functional relationship between saturation magnetization Ms and temperature T is employed in this paper to deduce the explicit mathematical expression among AVBJ vbar, stress σ, incentive magnetic field H and temperature T. Then the change law between AVBJ vbar and temperature T is researched according to the mathematical expression. Moreover, the tensile and compressive stress experiments are carried out on Q235 carbon steel specimens at different temperature to verify our theories. This paper offers a series of theoretical bases to solve the temperature compensation problem of Barkhausen testing method.

Relation between 1m depth temperature and average geothermal gradient at 75cm depth in geothermal fields

OpenAIRE

江原, 幸雄

2009-01-01

Shallow ground temperatures such as 1m depth temperature have been measured to delineate thermal anomalies of geothermal fields and also to estimate heat discharge rates from geothermal fields. As a result, a close linear relation between 1m depth temperature and average geothermal gradient at 75cm depth has been recognized in many geothermal fields and was used to estimate conductive heat discharge rates. However, such a linear relation may show that the shallow thermal regime in geothermal ...

Crowdsourcing urban air temperatures from smartphone battery temperatures

Science.gov (United States)

Overeem, Aart; Robinson, James C. R.; Leijnse, Hidde; Steeneveld, Gert-Jan; Horn, Berthold K. P.; Uijlenhoet, Remko

2014-05-01

Accurate air temperature observations in urban areas are important for meteorology and energy demand planning. They are indispensable to study the urban heat island effect and the adverse effects of high temperatures on human health. However, the availability of temperature observations in cities is often limited. Here we show that relatively accurate air temperature information for the urban canopy layer can be obtained from an alternative, nowadays omnipresent source: smartphones. In this study, battery temperatures were collected by an Android application for smartphones. It has been shown that a straightforward heat transfer model can be employed to estimate daily mean air temperatures from smartphone battery temperatures for eight major cities around the world. The results demonstrate the enormous potential of this crowdsourcing application for real-time temperature monitoring in densely populated areas. Battery temperature data were collected by users of an Android application for cell phones (opensignal.com). The application automatically sends battery temperature data to a server for storage. In this study, battery temperatures are averaged in space and time to obtain daily averaged battery temperatures for each city separately. A regression model, which can be related to a physical model, is employed to retrieve daily air temperatures from battery temperatures. The model is calibrated with observed air temperatures from a meteorological station of an airport located in or near the city. Time series of air temperatures are obtained for each city for a period of several months, where 50% of the data is for independent verification. The methodology has been applied to Buenos Aires, London, Los Angeles, Paris, Mexico City, Moscow, Rome, and Sao Paulo. The evolution of the retrieved air temperatures often correspond well with the observed ones. The mean absolute error of daily air temperatures is less than 2 degrees Celsius, and the bias is within 1 degree

Climate Prediction Center (CPC)Area-averaged 850-hPa Western Pacific Trade Wind Anomalies

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This is one of the CPC?s Monthly Atmospheric and SST Indices. It is the 850-hPa trade wind anomalies averaged over the area 5oN ? 5oS, 135oE-180o (western equatorial...

Climate Prediction Center (CPC)Area-averaged 850-hPa Eastern Pacific Trade Wind Anomalies

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This is one of the CPC?s Monthly Atmospheric and SST Indices. It is the 850-hPa trade wind anomalies averaged over the area 5oN ? 5oS, 135oW-120oW (eastern...

Climate Prediction Center (CPC)Area-averaged 850-hPa Central Pacific Trade Wind Anomalies

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This is one of the CPC?s Monthly Atmospheric and SST Indices. It is the 850-hPa trade wind anomalies averaged over the area 5oN ? 5oS, 175oW-140oW (central...

Perry Nuclear Power Plant Area/Equipment Temperature Monitoring Program

International Nuclear Information System (INIS)

McGuire, L.L.

1991-01-01

The Perry Nuclear Power Plant Area/Equipment Temperature Monitoring Program serves two purposes. The first is to track temperature trends during normal plant operation in areas where suspected deviations from established environmental profiles exist. This includes the use of Resistance Temperature Detectors, Recorders, and Temperature Dots for evaluation of equipment qualified life for comparison with tested parameters and the established Environmental Design Profile. It also may be used to determine the location and duration of steam leaks for effect on equipment qualified life. The second purpose of this program is to aid HVAC design engineers in determining the source of heat outside anticipated design parameters. Resistance Temperature Detectors, Recorders, and Temperature Dots are also used for this application but the results may include design changes to eliminate the excess heat or provide qualified equipment (cable) to withstand the elevated temperature, splitting of environmental zones to capture accurate temperature parameters, or continued environmental monitoring for evaluation of equipment located in hot spots

Soil respiration and carbon loss relationship with temperature and land use conversion in freeze-thaw agricultural area.

Science.gov (United States)

Ouyang, Wei; Lai, Xuehui; Li, Xia; Liu, Heying; Lin, Chunye; Hao, Fanghua

2015-11-15

Soil respiration (Rs) was hypothesized to have a special response pattern to soil temperature and land use conversion in the freeze-thaw area. The Rs differences of eight types of land use conversions during agricultural development were observed and the impacts of Rs on soil organic carbon (SOC) loss were assessed. The land use conversions during last three decades were categorized into eight types, and the 141 SOC sampling sites were grouped by conversion type. The typical soil sampling sites were subsequently selected for monitoring of soil temperature and Rs of each land use conversion types. The Rs correlations with temperature at difference depths and different conversion types were identified with statistical analysis. The empirical mean error model and the biophysical theoretical model with Arrhenius equation about the Rs sensitivity to temperature were both analyzed and shared the similar patterns. The temperature dependence of soil respiration (Q10) analysis further demonstrated that the averaged value of eight types of land use in this freeze-thaw agricultural area ranged from 1.15 to 1.73, which was lower than the other cold areas. The temperature dependence analysis demonstrated that the Rs in the top layer of natural land covers was more sensitive to temperature and experienced a large vertical difference. The natural land covers exhibited smaller Rs and the farmlands had the bigger value due to tillage practices. The positive relationships between SOC loss and Rs were identified, which demonstrated that Rs was the key chain for SOC loss during land use conversion. The spatial-vertical distributions of SOC concentration with the 1.5-km grid sampling showed that the more SOC loss in the farmland, which was coincided with the higher Rs in farmlands. The analysis of Rs dynamics provided an innovative explanation for SOC loss in the freeze-thaw agricultural area. The analysis of Rs dynamics provided an innovative explanation for SOC loss in the freeze

GOZCARDS Source Data for Temperature Monthly Zonal Averages on a Geodetic Latitude and Pressure Grid V1.00

Data.gov (United States)

National Aeronautics and Space Administration — The GOZCARDS Source Data for Temperature Monthly Zonal Averages on a Geodetic Latitude and Pressure Grid product (GozSmlpT) contains zonal means and related...

High-Temperature-Short-Time Annealing Process for High-Performance Large-Area Perovskite Solar Cells.

Science.gov (United States)

Kim, Minjin; Kim, Gi-Hwan; Oh, Kyoung Suk; Jo, Yimhyun; Yoon, Hyun; Kim, Ka-Hyun; Lee, Heon; Kim, Jin Young; Kim, Dong Suk

2017-06-27

Organic-inorganic hybrid metal halide perovskite solar cells (PSCs) are attracting tremendous research interest due to their high solar-to-electric power conversion efficiency with a high possibility of cost-effective fabrication and certified power conversion efficiency now exceeding 22%. Although many effective methods for their application have been developed over the past decade, their practical transition to large-size devices has been restricted by difficulties in achieving high performance. Here we report on the development of a simple and cost-effective production method with high-temperature and short-time annealing processing to obtain uniform, smooth, and large-size grain domains of perovskite films over large areas. With high-temperature short-time annealing at 400 °C for 4 s, the perovskite film with an average domain size of 1 μm was obtained, which resulted in fast solvent evaporation. Solar cells fabricated using this processing technique had a maximum power conversion efficiency exceeding 20% over a 0.1 cm 2 active area and 18% over a 1 cm 2 active area. We believe our approach will enable the realization of highly efficient large-area PCSs for practical development with a very simple and short-time procedure. This simple method should lead the field toward the fabrication of uniform large-scale perovskite films, which are necessary for the production of high-efficiency solar cells that may also be applicable to several other material systems for more widespread practical deployment.

Determination of the in-core power and the average core temperature of low power research reactors using gamma dose rate measurements

International Nuclear Information System (INIS)

Osei Poku, L.

2012-01-01

Most reactors incorporate out-of-core neutron detectors to monitor the reactor power. An accurate relationship between the powers indicated by these detectors and actual core thermal power is required. This relationship is established by calibrating the thermal power. The most common method used in calibrating the thermal power of low power reactors is neutron activation technique. To enhance the principle of multiplicity and diversity of measuring the thermal neutron flux and/or power and temperature difference and/or average core temperature of low power research reactors, an alternative and complimentary method has been developed, in addition to the current method. Thermal neutron flux/Power and temperature difference/average core temperature were correlated with measured gamma dose rate. The thermal neutron flux and power predicted using gamma dose rate measurement were in good agreement with the calibrated/indicated thermal neutron fluxes and powers. The predicted data was also good agreement with thermal neutron fluxes and powers obtained using the activation technique. At an indicated power of 30 kW, the gamma dose rate measured predicted thermal neutron flux of (1* 10 12 ± 0.00255 * 10 12 ) n/cm 2 s and (0.987* 10 12 ± 0.00243 * 10 12 ) which corresponded to powers of (30.06 ± 0.075) kW and (29.6 ± 0.073) for both normal level of the pool water and 40 cm below normal levels respectively. At an indicated power of 15 kW, the gamma dose rate measured predicted thermal neutron flux of (5.07* 10 11 ± 0.025* 10 11 ) n/cm 2 s and (5.12 * 10 11 ±0.024* 10 11 ) n/cm 2 s which corresponded to power of (15.21 ± 0.075) kW and (15.36 ± 0.073) kW for both normal levels of the pool water and 40 cm below normal levels respectively. The power predicted by this work also compared well with power obtained from a three-dimensional neutronic analysis for GHARR-1 core. The predicted power also compares well with calculated power using a correlation equation obtained from

Area-averaged surface fluxes and their time-space variability over the FIFE experimental domain

Science.gov (United States)

Smith, E. A.; Hsu, A. Y.; Crosson, W. L.; Field, R. T.; Fritschen, L. J.; Gurney, R. J.; Kanemasu, E. T.; Kustas, W. P.; Nie, D.; Shuttleworth, W. J.

1992-01-01

The underlying mean and variance properties of surface net radiation, sensible-latent heat fluxes and soil heat flux are studied over the densely instrumented grassland region encompassing FIFE. Flux variability is discussed together with the problem of scaling up to area-averaged fluxes. Results are compared and contrasted for cloudy and clear situations and examined for the influence of surface-induced biophysical controls (burn and grazing treatments) and topographic controls (aspect ratios and slope factors).

Dataset demonstrating the temperature effect on average output polarization for QCA based reversible logic gates

Directory of Open Access Journals (Sweden)

Md. Kamrul Hassan

2017-08-01

Full Text Available Quantum-dot cellular automata (QCA is a developing nanotechnology, which seems to be a good candidate to replace the conventional complementary metal-oxide-semiconductor (CMOS technology. In this article, we present the dataset of average output polarization (AOP for basic reversible logic gates presented in Ali Newaz et al. (2016 [1]. QCADesigner 2.0.3 has been employed to analysis the AOP of reversible gates at different temperature levels in Kelvin (K unit.

Improved averaging for non-null interferometry

Science.gov (United States)

Fleig, Jon F.; Murphy, Paul E.

2013-09-01

Arithmetic averaging of interferometric phase measurements is a well-established method for reducing the effects of time varying disturbances, such as air turbulence and vibration. Calculating a map of the standard deviation for each pixel in the average map can provide a useful estimate of its variability. However, phase maps of complex and/or high density fringe fields frequently contain defects that severely impair the effectiveness of simple phase averaging and bias the variability estimate. These defects include large or small-area phase unwrapping artifacts, large alignment components, and voids that change in number, location, or size. Inclusion of a single phase map with a large area defect into the average is usually sufficient to spoil the entire result. Small-area phase unwrapping and void defects may not render the average map metrologically useless, but they pessimistically bias the variance estimate for the overwhelming majority of the data. We present an algorithm that obtains phase average and variance estimates that are robust against both large and small-area phase defects. It identifies and rejects phase maps containing large area voids or unwrapping artifacts. It also identifies and prunes the unreliable areas of otherwise useful phase maps, and removes the effect of alignment drift from the variance estimate. The algorithm has several run-time adjustable parameters to adjust the rejection criteria for bad data. However, a single nominal setting has been effective over a wide range of conditions. This enhanced averaging algorithm can be efficiently integrated with the phase map acquisition process to minimize the number of phase samples required to approach the practical noise floor of the metrology environment.

Temperature environment for 9975 packages stored in KAC

Energy Technology Data Exchange (ETDEWEB)

Daugherty, W. L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-09-10

Plutonium materials are stored in the K Area Complex (KAC) in shipping packages, typically the 9975 shipping package. In order to estimate realistic degradation rates for components within the shipping package (i.e. the fiberboard overpack and O-ring seals), it is necessary to understand actual facility temperatures, which can vary daily and seasonally. Relevant facility temperature data available from several periods throughout its operating history have been reviewed. The annual average temperature within the Crane Maintenance Area has ranged from approximately 70 to 74 °F, although there is significant seasonal variation and lesser variation among different locations within the facility. The long-term average degradation rate for 9975 package components is very close to that expected if the component were to remain continually at the annual average temperature. This result remains valid for a wide range of activation energies (which describes the variation in degradation rate as the temperature changes), if the activation energy remains constant over the seasonal range of component temperatures. It is recommended that component degradation analyses and service life estimates incorporate these results. Specifically, it is proposed that future analyses assume an average facility ambient air temperature of 94 °F. This value is bounding for all packages, and includes margin for several factors such as increased temperatures within the storage arrays, the addition of more packages in the future, and future operational changes.

Lake Chad Total Surface Water Area as Derived from Land Surface Temperature and Radar Remote Sensing Data

Directory of Open Access Journals (Sweden)

Frederick Policelli

2018-02-01

Full Text Available Lake Chad, located in the middle of the African Sahel belt, underwent dramatic decreases in the 1970s and 1980s leaving less than ten percent of its 1960s surface water extent as open water. In this paper, we present an extended record (dry seasons 1988–2016 of the total surface water area of the lake (including both open water and flooded vegetation derived using Land Surface Temperature (LST data (dry seasons 2000–2016 from the NASA Terra MODIS sensor and EUMETSAT Meteosat-based LST measurements (dry seasons 1988–2001 from an earlier study. We also examine the total surface water area for Lake Chad using radar data (dry seasons 2015–2016 from the ESA Sentinel-1a mission. For the limited number of radar data sets available to us (18 data sets, we find on average a close match between the estimates from these data and the corresponding estimates from LST, though we find spatial differences in the estimates using the two types of data. We use these spatial differences to adjust the record (dry seasons 2000–2016 from MODIS LST. Then we use the adjusted record to remove the bias of the existing LST record (dry seasons 1988–2001 derived from Meteosat measurements and combine the two records. From this composite, extended record, we plot the total surface water area of the lake for the dry seasons of 1988–1989 through 2016–2017. We find for the dry seasons of 1988–1989 to 2016–2017 that the maximum total surface water area of the lake was approximately 16,800 sq. km (February and May, 2000, the minimum total surface water area of the lake was approximately 6400 sq. km (November, 1990, and the average was approximately 12,700 sq. km. Further, we find the total surface water area of the lake to be highly variable during this period, with an average rate of increase of approximately 143 km2 per year.

Dynamical and statistical downscaling of precipitation and temperature in a Mediterranean area

KAUST Repository

Pizzigalli, Claudia

2012-03-28

In this paper we present and discuss a comparison between statistical and regional climate modeling techniques for downscaling GCM prediction . The comparison is carried out over the “Capitanata” region, an area of agricultural interest in south-eastern Italy, for current (1961-1990) and future (2071–2100) climate. The statistical model is based on Canonical Correlation Analysis (CCA), associated with a data pre-filtering obtained by a Principal Component Analysis (PCA), whereas the Regional Climate Model REGCM3 was used for dynamical downscaling. Downscaling techniques were applied to estimate rainfall, maximum and minimum temperatures and average number of consecutive wet and dry days. Both methods have comparable skills in estimating stations data. They show good results for spring, the most important season for agriculture. Both statistical and dynamical models reproduce the statistical properties of precipitation well, the crucial variable for the growth of crops.

Isolated and synergistic effects of PM10 and average temperature on cardiovascular and respiratory mortality.

Science.gov (United States)

Pinheiro, Samya de Lara Lins de Araujo; Saldiva, Paulo Hilário Nascimento; Schwartz, Joel; Zanobetti, Antonella

2014-12-01

OBJECTIVE To analyze the effect of air pollution and temperature on mortality due to cardiovascular and respiratory diseases. METHODS We evaluated the isolated and synergistic effects of temperature and particulate matter with aerodynamic diameter mortality of individuals > 40 years old due to cardiovascular disease and that of individuals > 60 years old due to respiratory diseases in Sao Paulo, SP, Southeastern Brazil, between 1998 and 2008. Three methodologies were used to evaluate the isolated association: time-series analysis using Poisson regression model, bidirectional case-crossover analysis matched by period, and case-crossover analysis matched by the confounding factor, i.e., average temperature or pollutant concentration. The graphical representation of the response surface, generated by the interaction term between these factors added to the Poisson regression model, was interpreted to evaluate the synergistic effect of the risk factors. RESULTS No differences were observed between the results of the case-crossover and time-series analyses. The percentage change in the relative risk of cardiovascular and respiratory mortality was 0.85% (0.45;1.25) and 1.60% (0.74;2.46), respectively, due to an increase of 10 μg/m3 in the PM10 concentration. The pattern of correlation of the temperature with cardiovascular mortality was U-shaped and that with respiratory mortality was J-shaped, indicating an increased relative risk at high temperatures. The values for the interaction term indicated a higher relative risk for cardiovascular and respiratory mortalities at low temperatures and high temperatures, respectively, when the pollution levels reached approximately 60 μg/m3. CONCLUSIONS The positive association standardized in the Poisson regression model for pollutant concentration is not confounded by temperature, and the effect of temperature is not confounded by the pollutant levels in the time-series analysis. The simultaneous exposure to different levels of

Isolated and synergistic effects of PM10 and average temperature on cardiovascular and respiratory mortality

Directory of Open Access Journals (Sweden)

Samya de Lara Lins de Araujo Pinheiro

2014-12-01

Full Text Available OBJECTIVE To analyze the effect of air pollution and temperature on mortality due to cardiovascular and respiratory diseases. METHODS We evaluated the isolated and synergistic effects of temperature and particulate matter with aerodynamic diameter 40 years old due to cardiovascular disease and that of individuals > 60 years old due to respiratory diseases in Sao Paulo, SP, Southeastern Brazil, between 1998 and 2008. Three methodologies were used to evaluate the isolated association: time-series analysis using Poisson regression model, bidirectional case-crossover analysis matched by period, and case-crossover analysis matched by the confounding factor, i.e., average temperature or pollutant concentration. The graphical representation of the response surface, generated by the interaction term between these factors added to the Poisson regression model, was interpreted to evaluate the synergistic effect of the risk factors. RESULTS No differences were observed between the results of the case-crossover and time-series analyses. The percentage change in the relative risk of cardiovascular and respiratory mortality was 0.85% (0.45;1.25 and 1.60% (0.74;2.46, respectively, due to an increase of 10 μg/m3 in the PM10 concentration. The pattern of correlation of the temperature with cardiovascular mortality was U-shaped and that with respiratory mortality was J-shaped, indicating an increased relative risk at high temperatures. The values for the interaction term indicated a higher relative risk for cardiovascular and respiratory mortalities at low temperatures and high temperatures, respectively, when the pollution levels reached approximately 60 μg/m3. CONCLUSIONS The positive association standardized in the Poisson regression model for pollutant concentration is not confounded by temperature, and the effect of temperature is not confounded by the pollutant levels in the time-series analysis. The simultaneous exposure to different levels of

On the use of area-averaged void fraction and local bubble chord length entropies as two-phase flow regime indicators

International Nuclear Information System (INIS)

Hernandez, Leonor; Julia, J.E.; Paranjape, Sidharth; Hibiki, Takashi; Ishii, Mamoru

2010-01-01

In this work, the use of the area-averaged void fraction and bubble chord length entropies is introduced as flow regime indicators in two-phase flow systems. The entropy provides quantitative information about the disorder in the area-averaged void fraction or bubble chord length distributions. The CPDF (cumulative probability distribution function) of void fractions and bubble chord lengths obtained by means of impedance meters and conductivity probes are used to calculate both entropies. Entropy values for 242 flow conditions in upward two-phase flows in 25.4 and 50.8-mm pipes have been calculated. The measured conditions cover ranges from 0.13 to 5 m/s in the superficial liquid velocity j f and ranges from 0.01 to 25 m/s in the superficial gas velocity j g . The physical meaning of both entropies has been interpreted using the visual flow regime map information. The area-averaged void fraction and bubble chord length entropies capability as flow regime indicators have been checked with other statistical parameters and also with different input signals durations. The area-averaged void fraction and the bubble chord length entropies provide better or at least similar results than those obtained with other indicators that include more than one parameter. The entropy is capable to reduce the relevant information of the flow regimes in only one significant and useful parameter. In addition, the entropy computation time is shorter than the majority of the other indicators. The use of one parameter as input also represents faster predictions. (orig.)

Parametrization of the average ionization and radiative cooling rates of carbon plasmas in a wide range of density and temperature

OpenAIRE

Gil de la Fe, Juan Miguel; Rodriguez Perez, Rafael; Florido, Ricardo; Garcia Rubiano, Jesus; Mendoza, M.A.; Nuez, A. de la; Espinosa, G.; Martel Escobar, Carlos; Mínguez Torres, Emilio

2013-01-01

In this work we present an analysis of the influence of the thermodynamic regime on the monochromatic emissivity, the radiative power loss and the radiative cooling rate for optically thin carbon plasmas over a wide range of electron temperature and density assuming steady state situations. Furthermore, we propose analytical expressions depending on the electron density and temperature for the average ionization and cooling rate based on polynomial fittings which are valid for the whole range...

Winter temperatures in the second half of the sixteenth century in the central area of the Iberian Peninsula

Directory of Open Access Journals (Sweden)

T. Bullón

2008-12-01

Full Text Available This paper studies the winter temperatures of the second part of the sixteenth century in the central area of the Iberian Peninsula. A large number of historical documents that are stored in many different Spanish archives were consulted in order to carry out this research. The data was first arranged and weighted according to the intensity and significance of the meteorological phenomena described and, subsequently, these values were assigned an ordinal index ranging from +4 to −4. The statistical treatment applied is based on the reconstruction of temperatures equivalent to this ordinal index, expressed as anomalies of the 1961–1990 period, belonging to a reference station located at the approximate geographical center of the area under study. The results show winter thermal conditions different from current ones that, for the most part, stay below the reference average and that occurred with a wide range of variability. The influence that thermal conditions had on the evolution of some environmental aspects are considered based on the forest exploitation problem information and on the wine harvest production.

Parametrization of the average ionization and radiative cooling rates of carbon plasmas in a wide range of density and temperature

International Nuclear Information System (INIS)

Gil, J.M.; Rodriguez, R.; Florido, R.; Rubiano, J.G.; Mendoza, M.A.; Nuez, A. de la; Espinosa, G.; Martel, P.; Minguez, E.

2013-01-01

In this work we present an analysis of the influence of the thermodynamic regime on the monochromatic emissivity, the radiative power loss and the radiative cooling rate for optically thin carbon plasmas over a wide range of electron temperature and density assuming steady state situations. Furthermore, we propose analytical expressions depending on the electron density and temperature for the average ionization and cooling rate based on polynomial fittings which are valid for the whole range of plasma conditions considered in this work. -- Highlights: ► We compute the average ionization, cooling rates and emissivities of carbon plasmas. ► We compare LTE and NLTE calculations of these magnitudes. ► We perform a parametrization of these magnitudes in a wide range of plasma conditions. ► We provide information about where LTE regime assumption is accurate

Satellite monitoring temperature conditions spawning area of the Northeast Arctic cod in the Norwegian Sea and assessment its abundance

Science.gov (United States)

Vanyushin, George; Bulatova, Tatiana; Klochkov, Dmitriy; Troshkov, Anatoliy; Kruzhalov, Michail

2013-04-01

In this study, the attempt to consider the relationship between sea surface anomalies of temperature (SST anomalies °C) in spawning area of the Norwegian Arctic cod off the Lofoten islands in coastal zone of the Norwegian Sea and modern cod total stock biomass including forecasting assessment of future cod generation success. Continuous long-term database of the sea surface temperature (SST) was created on the NOAA satellites data. Mean monthly SST and SST anomalies are computed for the selected area on the basis of the weekly SST maps for the period of 1998-2012. These maps were plotted with the satellite SST data, as well as information of vessels, byoies and coastal stations. All data were classified by spawning seasons (March-April) and years. The results indicate that poor and low middle generations of cod (2001, 2006, 2007) occurred in years with negative or extremely high positive anomalies in the spawning area. The SST anomalies in years which were close to normal or some more normal significances provide conditions for appearance strong or very strong generations of cod (1998, 2000, 2002, 2004, 2005, 2006, 2008, 2009). Temperature conditions in concrete years influence on different indexes of cod directly. So, the mean temperature in spawning seasons in years 1999-2005 was ≈5,0°C and SST anomaly - +0,35°C, by the way average year significances indexes of cod were: total stock biomass - 1425,0 th.t., total spawning biomass - 460,0 th.t., recruitment (age 3+) - 535,0 mln. units and landings - 530,0 th.t. In spawning seasons 2006-2012 years the average data were following: mean SST ≈6,0°C, SST anomaly - +1,29°C, total stock biomass - 2185,0 th.t., total spawning biomass - 1211,0 th.t., recruitment (age 3+) - 821,0 mln. units and landings - 600,0 th.t. The SST and SST anomalies (the NOAA satellite data) characterize increase of decrease in input of warm Atlantic waters which form numerous eddies along the flows of the main warm currents thus creating

Area-averaged evapotranspiration over a heterogeneous land surface: aggregation of multi-point EC flux measurements with a high-resolution land-cover map and footprint analysis

Directory of Open Access Journals (Sweden)

F. Xu

2017-08-01

Full Text Available The determination of area-averaged evapotranspiration (ET at the satellite pixel scale/model grid scale over a heterogeneous land surface plays a significant role in developing and improving the parameterization schemes of the remote sensing based ET estimation models and general hydro-meteorological models. The Heihe Watershed Allied Telemetry Experimental Research (HiWATER flux matrix provided a unique opportunity to build an aggregation scheme for area-averaged fluxes. On the basis of the HiWATER flux matrix dataset and high-resolution land-cover map, this study focused on estimating the area-averaged ET over a heterogeneous landscape with footprint analysis and multivariate regression. The procedure is as follows. Firstly, quality control and uncertainty estimation for the data of the flux matrix, including 17 eddy-covariance (EC sites and four groups of large-aperture scintillometers (LASs, were carefully done. Secondly, the representativeness of each EC site was quantitatively evaluated; footprint analysis was also performed for each LAS path. Thirdly, based on the high-resolution land-cover map derived from aircraft remote sensing, a flux aggregation method was established combining footprint analysis and multiple-linear regression. Then, the area-averaged sensible heat fluxes obtained from the EC flux matrix were validated by the LAS measurements. Finally, the area-averaged ET of the kernel experimental area of HiWATER was estimated. Compared with the formerly used and rather simple approaches, such as the arithmetic average and area-weighted methods, the present scheme is not only with a much better database, but also has a solid grounding in physics and mathematics in the integration of area-averaged fluxes over a heterogeneous surface. Results from this study, both instantaneous and daily ET at the satellite pixel scale, can be used for the validation of relevant remote sensing models and land surface process models. Furthermore, this

Area-averaged evapotranspiration over a heterogeneous land surface: aggregation of multi-point EC flux measurements with a high-resolution land-cover map and footprint analysis

Science.gov (United States)

Xu, Feinan; Wang, Weizhen; Wang, Jiemin; Xu, Ziwei; Qi, Yuan; Wu, Yueru

2017-08-01

The determination of area-averaged evapotranspiration (ET) at the satellite pixel scale/model grid scale over a heterogeneous land surface plays a significant role in developing and improving the parameterization schemes of the remote sensing based ET estimation models and general hydro-meteorological models. The Heihe Watershed Allied Telemetry Experimental Research (HiWATER) flux matrix provided a unique opportunity to build an aggregation scheme for area-averaged fluxes. On the basis of the HiWATER flux matrix dataset and high-resolution land-cover map, this study focused on estimating the area-averaged ET over a heterogeneous landscape with footprint analysis and multivariate regression. The procedure is as follows. Firstly, quality control and uncertainty estimation for the data of the flux matrix, including 17 eddy-covariance (EC) sites and four groups of large-aperture scintillometers (LASs), were carefully done. Secondly, the representativeness of each EC site was quantitatively evaluated; footprint analysis was also performed for each LAS path. Thirdly, based on the high-resolution land-cover map derived from aircraft remote sensing, a flux aggregation method was established combining footprint analysis and multiple-linear regression. Then, the area-averaged sensible heat fluxes obtained from the EC flux matrix were validated by the LAS measurements. Finally, the area-averaged ET of the kernel experimental area of HiWATER was estimated. Compared with the formerly used and rather simple approaches, such as the arithmetic average and area-weighted methods, the present scheme is not only with a much better database, but also has a solid grounding in physics and mathematics in the integration of area-averaged fluxes over a heterogeneous surface. Results from this study, both instantaneous and daily ET at the satellite pixel scale, can be used for the validation of relevant remote sensing models and land surface process models. Furthermore, this work will be

Elevated CO2 Reduced Floret Death in Wheat Under Warmer Average Temperatures and Terminal Drought

Science.gov (United States)

Dias de Oliveira, Eduardo; Palta, Jairo A.; Bramley, Helen; Stefanova, Katia; Siddique, Kadambot H. M.

2015-01-01

Elevated CO2 often increases grain yield in wheat by enhancing grain number per ear, which can result from an increase in the potential number of florets or a reduction in the death of developed florets. The hypotheses that elevated CO2 reduces floret death rather than increases floret development, and that grain size in a genotype with more grains per unit area is limited by the rate of grain filling, were tested in a pair of sister lines contrasting in tillering capacity (restricted- vs. free-tillering). The hypotheses were tested under elevated CO2, combined with +3°C above ambient temperature and terminal drought, using specialized field tunnel houses. Elevated CO2 increased net leaf photosynthetic rates and likely the availability of carbon assimilates, which significantly reduced the rates of floret death and increased the potential number of grains at anthesis in both sister lines by an average of 42%. The restricted-tillering line had faster grain-filling rates than the free-tillering line because the free-tillering line had more grains to fill. Furthermore, grain-filling rates were faster under elevated CO2 and +3°C above ambient. Terminal drought reduced grain yield in both lines by 19%. Elevated CO2 alone increased the potential number of grains, but a trade-off in yield components limited grain yield in the free-tillering line. This emphasizes the need for breeding cultivars with a greater potential number of florets, since this was not affected by the predicted future climate variables. PMID:26635837

Elevated CO2 reduced floret death in wheat under warmer average temperatures and terminal drought.

Directory of Open Access Journals (Sweden)

Eduardo eDias de Oliveira

2015-11-01

Full Text Available Elevated CO2 often increases grain yield in wheat by enhancing grain number per ear, which can result from an increase in the potential number of florets or a reduction in the death of developed florets. The hypotheses that elevated CO2 reduces floret death rather than increases floret development, and that grain size in a genotype with more grains per unit area is limited by the rate of grain filling, were tested in a pair of sister lines contrasting in tillering capacity (restricted- vs free-tillering. The hypotheses were tested under elevated CO2, combined with +3 C above ambient temperature and terminal drought, using specialized field tunnel houses. Elevated CO2 increased net leaf photosynthetic rates and likely the availability of carbon assimilates, which significantly reduced the rates of floret death and increased the potential number of grains at anthesis in both sister lines by an average of 42%. The restricted-tillering line had faster grain-filling rates than the free-tillering line because the free-tillering line had more grains to fill. Furthermore, grain-filling rates were faster under elevated CO2 and +3 C above ambient. Terminal drought reduced grain yield in both lines by 19%. Elevated CO2 alone increased the potential number of grains, but a trade-off in yield components limited grain yield in the free-tillering line. This emphasizes the need for breeding cultivars with a greater potential number of florets, since this was not affected by the predicted future climate variables.

Average output polarization dataset for signifying the temperature influence for QCA designed reversible logic circuits.

Science.gov (United States)

Abdullah-Al-Shafi, Md; Bahar, Ali Newaz; Bhuiyan, Mohammad Maksudur Rahman; Shamim, S M; Ahmed, Kawser

2018-08-01

Quantum-dot cellular automata (QCA) as nanotechnology is a pledging contestant that has incredible prospective to substitute complementary metal-oxide-semiconductor (CMOS) because of its superior structures such as intensely high device thickness, minimal power depletion with rapid operation momentum. In this study, the dataset of average output polarization (AOP) for fundamental reversible logic circuits is organized as presented in (Abdullah-Al-Shafi and Bahar, 2017; Bahar et al., 2016; Abdullah-Al-Shafi et al., 2015; Abdullah-Al-Shafi, 2016) [1-4]. QCADesigner version 2.0.3 has been utilized to survey the AOP of reversible circuits at separate temperature point in Kelvin (K) unit.

Effect of gas temperature on flow rate characteristics of an averaging pitot tube type flow meter

Energy Technology Data Exchange (ETDEWEB)

Yeo, Seung Hwa; Lee, Su Ryong; Lee, Choong Hoon [Seoul National University of Science and Technology, Seoul (Korea, Republic of)

2015-01-15

The flow rate characteristics passing through an averaging Pitot tube (APT) while constantly controlling the flow temperature were studied through experiments and CFD simulations. At controlled temperatures of 25, 50, 75, and 100 .deg .C, the flow characteristics, in this case the upstream, downstream and static pressure at the APT flow meter probe, were measured as the flow rate was increased. The flow rate through the APT flow meter was represented using the H-parameter (hydraulic height) obtained by a combination of the differential pressure and the air density measured at the APT flow meter probe. Four types of H-parameters were defined depending on the specific combination. The flow rate and the upstream, downstream and static pressures measured at the APT flow meter while changing the H-parameters were simulated by means of CFD. The flow rate curves showed different features depending on which type of H-parameter was used. When using the constant air density value in a standard state to calculate the H-parameters, the flow rate increased linearly with the H-parameter and the slope of the flow rate curve according to the H-parameter increased as the controlled target air temperature was increased. When using different air density levels corresponding to each target air temperature to calculate the H-parameter, the slope of the flow rate curve according to the H-parameter was constant and the flow rate curve could be represented by a single line. The CFD simulation results were in good agreement with the experimental results. The CFD simulations were performed while increasing the air temperature to 1200 K. The CFD simulation results for high air temperatures were similar to those at the low temperature ranging from 25 to 100 .deg. C.

Effect of gas temperature on flow rate characteristics of an averaging pitot tube type flow meter

International Nuclear Information System (INIS)

Yeo, Seung Hwa; Lee, Su Ryong; Lee, Choong Hoon

2015-01-01

The flow rate characteristics passing through an averaging Pitot tube (APT) while constantly controlling the flow temperature were studied through experiments and CFD simulations. At controlled temperatures of 25, 50, 75, and 100 .deg .C, the flow characteristics, in this case the upstream, downstream and static pressure at the APT flow meter probe, were measured as the flow rate was increased. The flow rate through the APT flow meter was represented using the H-parameter (hydraulic height) obtained by a combination of the differential pressure and the air density measured at the APT flow meter probe. Four types of H-parameters were defined depending on the specific combination. The flow rate and the upstream, downstream and static pressures measured at the APT flow meter while changing the H-parameters were simulated by means of CFD. The flow rate curves showed different features depending on which type of H-parameter was used. When using the constant air density value in a standard state to calculate the H-parameters, the flow rate increased linearly with the H-parameter and the slope of the flow rate curve according to the H-parameter increased as the controlled target air temperature was increased. When using different air density levels corresponding to each target air temperature to calculate the H-parameter, the slope of the flow rate curve according to the H-parameter was constant and the flow rate curve could be represented by a single line. The CFD simulation results were in good agreement with the experimental results. The CFD simulations were performed while increasing the air temperature to 1200 K. The CFD simulation results for high air temperatures were similar to those at the low temperature ranging from 25 to 100 .deg. C.

Preferred temperature and thermal breadth of birds wintering in peninsular Spain: the limited effect of temperature on species distribution

Directory of Open Access Journals (Sweden)

Luis M. Carrascal

2016-07-01

Full Text Available Background. The availability of environmental energy, as measured by temperature, is expected to limit the abundance and distribution of endotherms wintering at temperate latitudes. A prediction of this hypothesis is that birds should attain their highest abundances in warmer areas. However, there may be a spatial mismatch between species preferred habitats and species preferred temperatures, so some species might end-up wintering in sub-optimal thermal environments. Methods. We model the influence of minimum winter temperature on the relative abundance of 106 terrestrial bird species wintering in peninsular Spain, at 10 ×10 km2 resolution, using 95%-quantile regressions. We analyze general trends across species on the shape of the response curves, the environmental preferred temperature (at which the species abundance is maximized, the mean temperature in the area of distribution and the thermal breadth (area under the abundance-temperature curve. Results. Temperature explains a low proportion of variation in abundance. The most significant effect is on limiting the maximum potential abundance of species. Considering this upper-limit response, there is a large interspecific variability on the thermal preferences and specialization of species. Overall, there is a preponderance of positive relationships between species abundance and temperature; on average, species attain their maximum abundances in areas 1.9 °C warmer than the average temperature available in peninsular Spain. The mean temperature in the area of distribution is lower than the thermal preferences of the species. Discussion. Many species prefer the warmest areas to overwinter, which suggests that temperature imposes important restrictions to birds wintering in the Iberian Peninsula. However, one third of species overwinter in locations colder than their thermal preferences, probably reflecting the interaction between habitat and thermal requirements. There is a high inter

Design A Prototype of Temperature Logging Tools for Geothermal Prospecting Areas

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Supriyanto

2013-08-01

Full Text Available The costs of geothermal exploration are very high because technology is still imported from other countries. The local business players in the geothermal sector do not have the ability to compete with global companies. To reduce costs, we need to develop our own equipment with competitive prices. Here in Indonesia, we have started to design a prototype of temperature logging tools for geothermal prospecting areas. This equipment can be used to detect temperature versus depth variations. To measure the thermal gradient, the platinum resistor temperature sensor is moved slowly down along the borehole. The displacement along the borehole is measured by a rotary encoder. This system is controlled by a 16-bit H8/3069F microcontroller. The acquired temperature data is displayed on a PC monitor using a Python Graphical User Interface. The system has been already tested in the Gunung Pancar geothermal prospect area in Bogor.

1994 Average Monthly Sea Surface Temperature for California

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA/ NASA AVHRR Oceans Pathfinder sea surface temperature data are derived from the 5-channel Advanced Very High Resolution Radiometers (AVHRR) on board the...

[Etiological analysis of subambient temperature burn in 351 cases of Hefei area].

Science.gov (United States)

Shi, Jie; Qi, Weiwei; Xu, Qinglian; Zhou, Shunying; Wang, Guobao

2010-06-01

To study the preventive measure of the subambient temperature burn by analysing the pathogenesis feature. The clinical data were analysed from 351 cases of subambient temperature burn between February 2004 and February 2009, including age, sex, burn season, burn factors, burn position, burn area, burn degree, treatment way, and wound healing. Subambient temperature burn occurred in every age stage. The susceptible age stages included infant, children, and the elderly. Female patients were more than male patients. The common burn reasons were hot-water bottle burn, honey warm keeper burn, and heating device burn. The peak season was winter. Lower limb was the most common site of the subambient temperature burn. The deep II degree to III degree were the most common level, and the burn area was always small, often time safety awareness should be strengthened so as to decrease the incidence rate of subambient temperature burn and the injury degree.

1993 Average Monthly Sea Surface Temperature for California

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA/NASA AVHRR Oceans Pathfinder sea surface temperature data are derived from the 5-channel Advanced Very High Resolution Radiometers (AVHRR) on board the NOAA...

Airborne-Measured Spatially-Averaged Temperature and Moisture Turbulent Structure Parameters Over a Heterogeneous Surface

Science.gov (United States)

Platis, Andreas; Martinez, Daniel; Bange, Jens

2014-05-01

Turbulent structure parameters of temperature and humidity can be derived from scintillometer measurements along horizontal paths of several 100 m to several 10 km. These parameters can be very useful to estimate the vertical turbulent heat fluxes at the surface (applying MOST). However, there are many assumptions required by this method which can be checked using in situ data, e.g. 1) Were CT2 and CQ2 correctly derived from the initial CN2 scintillometer data (structure parameter of density fluctuations or refraction index, respectively)? 2) What is the influence of the surround hetereogeneous surface regarding its footprint and the weighted averaging effect of the scintillometer method 3) Does MOST provide the correct turbulent fluxes from scintillometer data. To check these issues, in situ data from low-level flight measurements are well suited, since research aircraft cover horizontal distances in very short time (Taylor's hypothesis of a frozen turbulence structure can be applyed very likely). From airborne-measured time series the spatial series are calculated and then their structure functions that finally provide the structure parameters. The influence of the heterogeneous surface can be controlled by the definition of certain moving-average window sizes. A very useful instrument for this task are UAVs since they can fly very low and maintain altitude very precisely. However, the data base of such unmanned operations is still quite thin. So in this contribution we want to present turbulence data obtained with the Helipod, a turbulence probe hanging below a manned helicopter. The structure parameters of temperature and moisture, CT2 and CQ2, in the lower convective boundary layer were derived from data measured using the Helipod in 2003. The measurements were carried out during the LITFASS03 campaign over a heterogeneous land surface around the boundary-layer field site of the Lindenberg Meteorological Observatory-Richard-Aßmann-Observatory (MOL) of the

Global Warming: The Instability of Desert Climate is Enhancing in the Northwest Area in China: A Case Study in the Desert Area in Northwestern China

OpenAIRE

Zhao-Feng Chang; Shu-Juan Zhu; Fu-Gui Han; Sheng-Nnian Zhong; Qiang-Qiang Wang; Jian-Hui Zhang

2013-01-01

To disclose the relation between the sandstorms change and the temperature changes, a case study in the desert area in northwestern china is investigated. The results showed that: the instability of climate in Minqin desert area is enhancing in the arid desert region in northwest China. Mainly as follows: Variation the annual extreme maximum temperature increasing. Variation of extreme minimum temperature also an increasing trend. Average visibility of sandstorms significantly reduced and the...

Average Revisited in Context

Science.gov (United States)

Watson, Jane; Chick, Helen

2012-01-01

This paper analyses the responses of 247 middle school students to items requiring the concept of average in three different contexts: a city's weather reported in maximum daily temperature, the number of children in a family, and the price of houses. The mixed but overall disappointing performance on the six items in the three contexts indicates…

Reactor Coolant Temperature Measurement using Ultrasonic Technology

Energy Technology Data Exchange (ETDEWEB)

Jung, JaeCheon [KEPCO International Nuclear graduate School, Ulsan (Korea, Republic of); Seo, YongSun; Bechue, Nicholas [Krohne Messtechnik GmbH, Duisburg (Germany)

2016-10-15

In NPP, the primary piping temperature is detected by four redundant RTDs (Resistance Temperature Detectors) installed 90 degrees apart on the RCS (Reactor Coolant System) piping circumferentially. Such outputs however, if applied to I and C systems would not give balanced results. The discrepancy can be explained by either thermal stratification or improper arrangement of thermo-wells and RTDs. This phenomenon has become more pronounced in the hot-leg piping than in the cold-leg. Normally, the temperature difference among channels is in the range of 1°F in Korean nuclear power Plants. Consequently, a more accurate pipe average temperate measurement technique is required. Ultrasonic methods can be used to measure average temperatures with relatively higher accuracy than RTDs because the sound wave propagation in the RCS pipe is proportional to the average temperature around pipe area. The inaccuracy of RCS temperature measurement worsens the safety margin for both DNBR and LPD. The possibility of this discrepancy has been reported with thermal stratification effect. Proposed RCS temperature measurement system based on ultrasonic technology offers a countermeasure to cope with thermal stratification effect on hot-leg piping that has been an unresolved issue in NPPs. By introducing ultrasonic technology, the average internal piping temperature can be measured with high accuracy. The inaccuracy can be decreased less than ±1℉ by this method.

Analysis of Applicability of Flow Averaging Pitot Tubes in the Areas of Flow Disturbance

Directory of Open Access Journals (Sweden)

Pochwała Sławomir

2016-03-01

Full Text Available The issues connected with the complex design of various facilities, including up-to-date boiler equipment as well as the ways of organizing the space around them, are the reasons why there is often a lack of room for mounting a flowmeter in accordance with the recommendations of manufacturers. In most cases the problem is associated with ensuring sufficient lengths of straight pipe leading into and out of a flowmeter. When this condition cannot be fulfilled, the uncertainty of measurement increases above the value guaranteed by the manufacturer of the flowmeter. This sort of operation problem has encouraged the authors of this paper to undertake research aimed at the analysis of applicability of averaging Pitot tubes in the areas of flow disturbance.

Field test analysis of concentrator photovoltaic system focusing on average photon energy and temperature

Science.gov (United States)

Husna, Husyira Al; Ota, Yasuyuki; Minemoto, Takashi; Nishioka, Kensuke

2015-08-01

The concentrator photovoltaic (CPV) system is unique and different from the common flat-plate PV system. It uses a multi-junction solar cell and a Fresnel lens to concentrate direct solar radiation onto the cell while tracking the sun throughout the day. The cell efficiency could reach over 40% under high concentration ratio. In this study, we analyzed a one year set of environmental condition data of the University of Miyazaki, Japan, where the CPV system was installed. Performance ratio (PR) was discussed to describe the system’s performance. Meanwhile, the average photon energy (APE) was used to describe the spectrum distribution at the site where the CPV system was installed. A circuit simulator network was used to simulate the CPV system electrical characteristics under various environmental conditions. As for the result, we found that the PR of the CPV systems depends on the APE level rather than the cell temperature.

Average monthly and annual climate maps for Bolivia

KAUST Repository

Vicente-Serrano, Sergio M.

2015-02-24

This study presents monthly and annual climate maps for relevant hydroclimatic variables in Bolivia. We used the most complete network of precipitation and temperature stations available in Bolivia, which passed a careful quality control and temporal homogenization procedure. Monthly average maps at the spatial resolution of 1 km were modeled by means of a regression-based approach using topographic and geographic variables as predictors. The monthly average maximum and minimum temperatures, precipitation and potential exoatmospheric solar radiation under clear sky conditions are used to estimate the monthly average atmospheric evaporative demand by means of the Hargreaves model. Finally, the average water balance is estimated on a monthly and annual scale for each 1 km cell by means of the difference between precipitation and atmospheric evaporative demand. The digital layers used to create the maps are available in the digital repository of the Spanish National Research Council.

Satellite-derived ice data sets no. 2: Arctic monthly average microwave brightness temperatures and sea ice concentrations, 1973-1976

Science.gov (United States)

Parkinson, C. L.; Comiso, J. C.; Zwally, H. J.

1987-01-01

A summary data set for four years (mid 70's) of Arctic sea ice conditions is available on magnetic tape. The data include monthly and yearly averaged Nimbus 5 electrically scanning microwave radiometer (ESMR) brightness temperatures, an ice concentration parameter derived from the brightness temperatures, monthly climatological surface air temperatures, and monthly climatological sea level pressures. All data matrices are applied to 293 by 293 grids that cover a polar stereographic map enclosing the 50 deg N latitude circle. The grid size varies from about 32 X 32 km at the poles to about 28 X 28 km at 50 deg N. The ice concentration parameter is calculated assuming that the field of view contains only open water and first-year ice with an ice emissivity of 0.92. To account for the presence of multiyear ice, a nomogram is provided relating the ice concentration parameter, the total ice concentration, and the fraction of the ice cover which is multiyear ice.

Galileo SSI and Cassini ISS Observations of Io's Pele Hotspot: Temperatures, Areas, and Variation with Time

Science.gov (United States)

Radebaugh, J.; McEwen, A. S.; Milazzo, M.; Davies, A. G.; Keszthelyi, L. P.; Geissler, P.

2002-01-01

Temperatures of Io's Pele hotspot were found using dual-filter observations from Galileo and Cassini. Temperatures average 1375 K, but vary widely over tens of minutes. Dropoff in emission with rotation consistent with lava fountaining at a lava lake. Additional information is contained in the original extended abstract.

Average-atom model for two-temperature states and ionic transport properties of aluminum in the warm dense matter regime

Science.gov (United States)

Hou, Yong; Fu, Yongsheng; Bredow, Richard; Kang, Dongdong; Redmer, Ronald; Yuan, Jianmin

2017-03-01

The average-atom model combined with the hyper-netted chain approximation is an efficient tool for electronic and ionic structure calculations for warm dense matter. Here we generalize this method in order to describe non-equilibrium states with different electron and ion temperature as produced in laser-matter interactions on ultra-short time scales. In particular, the electron-ion and ion-ion correlation effects are considered when calculating the electron structure. We derive an effective ion-ion pair-potential using the electron densities in the framework of temperature-depended density functional theory. Using this ion-ion potential we perform molecular dynamics simulations in order to determine the ionic transport properties such as the ionic diffusion coefficient and the shear viscosity through the ionic velocity autocorrelation functions.

Operator product expansion and its thermal average

Energy Technology Data Exchange (ETDEWEB)

Mallik, S [Saha Inst. of Nuclear Physics, Calcutta (India)

1998-05-01

QCD sum rules at finite temperature, like the ones at zero temperature, require the coefficients of local operators, which arise in the short distance expansion of the thermal average of two-point functions of currents. We extend the configuration space method, applied earlier at zero temperature, to the case at finite temperature. We find that, upto dimension four, two new operators arise, in addition to the two appearing already in the vacuum correlation functions. It is argued that the new operators would contribute substantially to the sum rules, when the temperature is not too low. (orig.) 7 refs.

Radiative surface temperatures of the burned and unburned areas in a tallgrass prairie

International Nuclear Information System (INIS)

Asrar, G.; Harris, T.R.; Lapitan, R.L.; Cooper, D.I.

1988-01-01

This study was conducted in a natural tallgrass prairie area in the Flint Hills of Kansas. Our objective was to evaluate the surface radiative temperatures of burned and unburned treatments of the grassland as a means of delineating the areas covered by each treatment. Burning is used to remove the senescent vegetation resulting from the previous year's growth. Surface temperatures were obtained in situ and by an airborne scanner. Burned and unburned grass canopies had distinctly different diurnal surface radiative temperatures. Measurements of surface energy balance components revealed a difference in partitioning of the available energy between the two canopies, which resulted in the difference in their measured surface temperatures. The magnitude of this difference is dependent on the time of measurements and topographic conditions. (author)

Modeling the Distributions of Brightness Temperatures of a Cropland Study Area Using a Model that Combines Fast Radiosity and Energy Budget Methods

Directory of Open Access Journals (Sweden)

Zunjian Bian

2018-05-01

Full Text Available Land surface temperatures (LSTs obtained from remote sensing data are crucial in monitoring the conditions of crops and urban heat islands. However, since retrieved LSTs represent only the average temperature states of pixels, the distributions of temperatures within individual pixels remain unknown. Such data cannot satisfy the requirements of applications such as precision agriculture. Therefore, in this paper, we propose a model that combines a fast radiosity model, the Radiosity Applicable to Porous IndiviDual Objects (RAPID model, and energy budget methods to dynamically simulate brightness temperatures (BTs over complex surfaces. This model represents a model-based tool that can be used to estimate temperature distributions using fine-scale visible as well as near-infrared (VNIR data and temporal variations in meteorological conditions. The proposed model is tested over a study area in an artificial oasis in Northwestern China. The simulated BTs agree well with those measured with the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER. The results reflect root mean squared errors (RMSEs less than 1.6 °C and coefficients of determination (R2 greater than 0.7. In addition, compared to the leaf area index (LAI, this model displays high sensitivity to wind speed during validation. Although simplifications may be adopted for use in specific simulations, this proposed model can be used to support in situ measurements and to provide reference data over heterogeneous vegetation surfaces.

Low temperature diamond growth by linear antenna plasma CVD over large area

International Nuclear Information System (INIS)

Izak, Tibor; Babchenko, Oleg; Potocky, Stepan; Kromka, Alexander; Varga, Marian

2012-01-01

Recently, there is a great effort to increase the deposition area and decrease the process temperature for diamond growth which will enlarge its applications including use of temperature sensitive substrates. In this work, we report on the large area (20 x 30 cm 2 ) and low temperature (250 C) polycrystalline diamond growth by pulsed linear antenna microwave plasma system. The influence of substrate temperature varied from 250 to 680 C, as controlled by the table heater and/or by microwave power, is studied. It was found that the growth rate, film morphology and diamond to non-diamond phases (sp 3 /sp 2 carbon bonds) are influenced by the growth temperature, as confirmed by SEM and Raman measurements. The surface chemistry and growth processes were studied in terms of activation energies (E a ) calculated from Arrhenius plots. The activation energies of growth processes were very low (1.7 and 7.8 kcal mol -1 ) indicating an energetically favourable growth process from the CO 2 -CH 4 -H 2 gas mixture. In addition, from activation energies two different growth regimes were observed at low and high temperatures, indicating different growth mechanism. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Monitoring actual temperatures in Susquehanna SES reactor buildings

International Nuclear Information System (INIS)

Derkacs, A.P.

1991-01-01

PP and L has been monitoring temperatures in the Susquehanna SES reactor building with digital temperature recorders since 1986. In early 1990, data from four representative areas was analyzed to determine the temperature in each area which would produce the same rate of degradation as the distribution of actual temperatures recorded over about 40 months. From these effective average temperatures, qualified life multipliers were determined for activation energies in the range of 0.5 to 1.5 and those multipliers were used to estimate new qualified lives and the number of replacements which might be saved during the life of the plant. The results indicate that pursuing a program of determining EQ qualified lives from actual temperatures, rather than maximum design basis temperatures, will provide a substantial payback in reduced EQ driven maintenance

CO2 and temperature effects on leaf area production in two annual plant species

International Nuclear Information System (INIS)

Ackerly, D.D.; Coleman, J.S.; Morse, S.R.; Bazzaz, F.A.

1992-01-01

The authors studied leaf area production in two annual plant species, Abutilon theophrasti and Amaranthus retroflexus, under three day/night temperature regimes and two concentrations of carbon dioxide. The production of whole-plant leaf area during the first 30 d of growth was analyzed in terms of the leaf initiation rate, leaf expansion, individual leaf area, and, in Amaranthus, production of branch leaves. Temperature and CO 2 influenced leaf area production through effects on the rate of development, determined by the production of nodes on the main stem, and through shifts in the relationship between whole-plant leaf area and the number of main stem nodes. In Abutilon, leaf initiation rate was highest at 38 degree, but area of individual leaves was greatest at 28 degree. Total leaf area was greatly reduced at 18 degree due to slow leaf initiation rates. Elevated CO 2 concentration increased leaf initiation rate at 28 degree, resulting in an increase in whole-part leaf area. In Amaranthus, leaf initiation rate increased with temperature, and was increased by elevated CO 2 at 28 degree. Individual leaf area was greatest at 28 degree, and was increased by elevated CO 2 at 28 degree but decreased at 38 degree. Branch leaf area displayed a similar response to CO 2 , butt was greater at 38 degree. Overall, wholeplant leaf area was slightly increased at 38 degree relative to 28 degree, and elevated CO 2 levels resulted in increased leaf area at 28 degree but decreased leaf area at 38 degree

Influence of engine speed and the course of the fuel injection characteristics on forming the average combustion temperature in the cylinder of turbo diesel engine

Directory of Open Access Journals (Sweden)

Piotr GUSTOF

2007-01-01

Full Text Available Average combustion temperatures inside a turbo diesel engine for the same load and the same total doze of fuel for two rotational speeds: 2004 [rpm] and 4250 [rpm] are presented in this paper. The aim of this work is also the evaluation of the influence of the temporary course of the fuel injection characteristics on forming temperature in theengine cylinder space for these temperatures. The calculations were carried out by means of two zone combustion model.

Crystallographic extraction and averaging of data from small image areas

NARCIS (Netherlands)

Perkins, GA; Downing, KH; Glaeser, RM

The accuracy of structure factor phases determined from electron microscope images is determined mainly by the level of statistical significance, which is limited by the low level of allowed electron exposure and by the number of identical unit cells that can be averaged. It is shown here that

Remote sensing of temperature and wind using acoustic travel-time measurements

Energy Technology Data Exchange (ETDEWEB)

Barth, Manuela; Fischer, Gabi; Raabe, Armin; Weisse, Frank [Leipzig Univ. (Germany). Inst. fuer Meteorologie; Ziemann, Astrid [Technische Univ. Dresden (Germany). Professur fuer Meteorologie

2013-04-15

A remote sensing technique to detect area-averaged temperature and flow properties within an area under investigation, utilizing acoustic travel-time measurements, is introduced. This technique uses the dependency of the speed of acoustic signals on the meteorological parameters temperature and wind along the propagation path. The method itself is scalable: It is applicable for investigation areas with an extent of some hundred square metres as well as for small-scale areas in the range of one square metre. Moreover, an arrangement of the acoustic transducers at several height levels makes it possible to determine profiles and gradients of the meteorological quantities. With the help of two examples the potential of this remote sensing technique for simultaneously measuring averaged temperature and flow fields is demonstrated. A comparison of time histories of temperature and wind values derived from acoustic travel-time measurements with point measurements shows a qualitative agreement whereas calculated root-mean-square errors differ for the two example applications. They amount to 1.4 K and 0.3 m/s for transducer distances of 60 m and 0.4 K and 0.2 m/s for transducer distances in the range of one metre. (orig.)

European temperature responses to blocking and ridge regional patterns

Science.gov (United States)

Sousa, Pedro M.; Trigo, Ricardo M.; Barriopedro, David; Soares, Pedro M. M.; Santos, João A.

2018-01-01

Blocking occurrence and its impacts on European temperature have been studied in the last decade. However, most previous studies on blocking impacts have focused on winter only, disregarding its fingerprint in summer and differences with other synoptic patterns that also trigger temperature extremes. In this work, we provide a clear distinction between high-latitude blocking and sub-tropical ridges occurring in three sectors of the Euro-Atlantic region, describing their climatology and consequent impacts on European temperature during both winter and summer. Winter blocks (ridges) are generally associated to colder (warmer) than average conditions over large regions of Europe, in some areas with anomalies larger than 5 °C, particularly for the patterns occurring in the Atlantic and Central European sectors. During summer, there is a more regional response characterized by above average temperature for both blocking and ridge patterns, especially those occurring in continental areas, although negative temperature anomalies persist in southernmost areas during blocking. An objective analysis of the different forcing mechanisms associated to each considered weather regime has been performed, quantifying the importance of the following processes in causing the temperature anomalies: horizontal advection, vertical advection and diabatic heating. While during winter advection processes tend to be more relevant to explain temperature responses, in summer radiative heating under enhanced insolation plays a crucial role for both blocking and ridges. Finally, the changes in the distributions of seasonal temperature and in the frequencies of extreme temperature indices were also examined for specific areas of Europe. Winter blocking and ridge patterns are key drivers in the occurrence of regional cold and warm extreme temperatures, respectively. In summer, they are associated with substantial changes in the frequency of extremely warm days, but with different signatures in

Development of large-area high-temperature fixed-point blackbodies for photometry and radiometry

Science.gov (United States)

Khlevnoy, Boris; Grigoryeva, Irina; Anhalt, Klaus; Waehmer, Martin; Ivashin, Evgeniy; Otryaskin, Denis; Solodilov, Maxim; Sapritsky, Victor

2018-04-01

Large-area high-temperature fixed-point (HTFP) blackbodies with working temperatures of approximately 2748 K and 3021 K, based on an Re-C eutectic and a WC-C peritectic respectively, have been developed and investigated. The blackbodies have an emissivity of 0.9997, show high-quality phase-transition plateaus and have high repeatability of the melting temperatures, but demonstrate temperature differences (from 0.2 K to 0.6 K) compared with small-cell blackbodies of the same HTFP. We associate these temperature differences with the temperature drop effect, which may differ from cell to cell. The large radiating cavity diameter of 14 mm allows developed HTFP blackbodies to be used for photometric and radiometric applications in irradiance mode with uncertainties as small as 0.12% (k  =  1) in the visible. A photometer and an irradiance-mode filter radiometer (visible range), previously calibrated at VNIIOFI, were used to measure illuminance and irradiance of the HTFP blackbodies equipped with a precise outer aperture. The values measured by the detectors agreed with those based on the blackbody calculation to within 0.2%. The large-area HTFP blackbodies will be used in a joint PTB-VNIIOFI experiment on measuring thermodynamic temperature.

Temperature minima in the average thermal structure of the middle mesosphere (70 - 80 km) from analysis of 40- to 92-km SME global temperature profiles

Science.gov (United States)

Clancy, R. Todd; Rusch, David W.; Callan, Michael T.

1994-01-01

Global temperatures have been derived for the upper stratosphere and mesosphere from analysis of Solar Mesosphere Explorer (SME) limb radiance profiles. The SME temperature represent fixed local time observations at 1400 - 1500 LT, with partial zonal coverage of 3 - 5 longitudes per day over the 1982-1986 period. These new SME temperatures are compared to the COSPAR International Ionosphere Reference Atmosphere 86 (CIRA 86) climatology (Fleming et al., 1990) as well as stratospheric and mesospheric sounder (SAMS); Barnett and Corney, 1984), National Meteorological Center (NMC); (Gelman et al., 1986), and individual lidar and rocket observations. Significant areas of disagreement between the SME and CIRA 86 mesospheric temperatures are 10 K warmer SME temperatures at altitudes above 80 km. The 1981-1982 SAMS temperatures are in much closer agreement with the SME temperatures between 40 and 75 km. Although much of the SME-CIRA 86 disagreement probably stems from the poor vertical resolution of the observations comprising the CIRA 86 modelm, some portion of the differences may reflect 5- to 10-year temporal variations in mesospheric temperatures. The CIRA 86 climatology is based on 1973-1978 measurements. Relatively large (1 K/yr) 5- to 10-year trends in temperatures as functions of longitude, latitude, and altitude have been observed for both the upper stratosphere (Clancy and Rusch, 1989a) and mesosphere (Clancy and Rusch, 1989b; Hauchecorne et al., 1991). The SME temperatures also exhibit enhanced amplitudes for the semiannual oscillation (SAO) of upper mesospheric temperatures at low latitudes, which are not evident in the CIRA 86 climatology. The so-called mesospheric `temperature inversions' at wintertime midlatitudes, which have been observed by ground-based lidar (Hauschecorne et al., 1987) and rocket in situ measurements (Schmidlin, 1976), are shown to be a climatological aspect of the mesosphere, based on the SME observations.

Relationship among land surface temperature and LUCC, NDVI in typical karst area.

Science.gov (United States)

Deng, Yuanhong; Wang, Shijie; Bai, Xiaoyong; Tian, Yichao; Wu, Luhua; Xiao, Jianyong; Chen, Fei; Qian, Qinghuan

2018-01-12

Land surface temperature (LST) can reflect the land surface water-heat exchange process comprehensively, which is considerably significant to the study of environmental change. However, research about LST in karst mountain areas with complex topography is scarce. Therefore, we retrieved the LST in a karst mountain area from Landsat 8 data and explored its relationships with LUCC and NDVI. The results showed that LST of the study area was noticeably affected by altitude and underlying surface type. In summer, abnormal high-temperature zones were observed in the study area, perhaps due to karst rocky desertification. LSTs among different land use types significantly differed with the highest in construction land and the lowest in woodland. The spatial distributions of NDVI and LST exhibited opposite patterns. Under the spatial combination of different land use types, the LST-NDVI feature space showed an obtuse-angled triangle shape and showed a negative linear correlation after removing water body data. In summary, the LST can be retrieved well by the atmospheric correction model from Landsat 8 data. Moreover, the LST of the karst mountain area is controlled by altitude, underlying surface type and aspect. This study provides a reference for land use planning, ecological environment restoration in karst areas.

Stream water temperature limits occupancy of salamanders in mid-Atlantic protected areas

Science.gov (United States)

Grant, Evan H. Campbell; Wiewel, Amber N. M.; Rice, Karen C.

2014-01-01

Stream ecosystems are particularly sensitive to urbanization, and tolerance of water-quality parameters is likely important to population persistence of stream salamanders. Forecasted climate and landscape changes may lead to significant changes in stream flow, chemical composition, and temperatures in coming decades. Protected areas where landscape alterations are minimized will therefore become increasingly important for salamander populations. We surveyed 29 streams at three national parks in the highly urbanized greater metropolitan area of Washington, DC. We investigated relationships among water-quality variables and occupancy of three species of stream salamanders (Desmognathus fuscus, Eurycea bislineata, and Pseudotriton ruber). With the use of a set of site-occupancy models, and accounting for imperfect detection, we found that stream-water temperature limits salamander occupancy. There was substantial uncertainty about the effects of the other water-quality variables, although both specific conductance (SC) and pH were included in competitive models. Our estimates of occupancy suggest that temperature, SC, and pH have some importance in structuring stream salamander distribution.

Average opportunity-based accessibility of public transit systems to grocery stores in small urban areas

Directory of Open Access Journals (Sweden)

Nimish Dharmadhikari

2015-12-01

Full Text Available This research studies the accessibility of grocery stores to university students using the public transportation system, drawing from a case study of Fargo, North Dakota. Taking into consideration the combined travel time components of walking, riding, and waiting, this study measures two types of accessibilities: accessibility to reach a particular place and accessibility to reach the bus stop to ride the public transit system. These two accessibilities are interdependent and cannot perform without each other. A new method to calculate the average accessibility measure for the transit routes is proposed. A step-wise case study analysis indicates that one route provides accessibility to a grocery store in eight minutes. This also suggests that the North Dakota State University area has moderate accessibility to grocery stores.

Determining average yarding distance.

Science.gov (United States)

Roger H. Twito; Charles N. Mann

1979-01-01

Emphasis on environmental and esthetic quality in timber harvesting has brought about increased use of complex boundaries of cutting units and a consequent need for a rapid and accurate method of determining the average yarding distance and area of these units. These values, needed for evaluation of road and landing locations in planning timber harvests, are easily and...

Estimation of subsurface formation temperature in the Yangtze area, South China: implications for shale gas generation and preservation

Science.gov (United States)

Liu, S.; Hao, C.; Li, X.; Xu, M.

2015-12-01

Temperature is one key parameter for hydrocarbon generation and preservation, also playing important role in geothermal energy assessment;however, accurate regional temperature pattern is still challenging, owing to a lack of data coverage and data quality as well. The Yangtze area, located in the South China, is considered as the most favorable target for shale gas resource exploration in China, and attracts more and more attention recently. Here we used the newly acquired steady-state temperature loggings, reliable Drilling Stem Test temperature data available and thermal properties, estimated the subsurface temperature-at-depth for the Yangtze area. Results show that the geothermal gradient ranges between 17 K/m and 74K/m, mainly falling into 20~30K/m, with a mean of 24 K/m; heat flow varies from 25 mW/m2 to 92 mW/m2, with a mean of 65 mW/m2. For the estimated temperature-at-depth, it is about 20~50 ℃ at the depth of 1000m, 50~80℃ for that at 2000m; while the highest temperature can be up to 110℃ at 3000m depth. Generally, the present-day geothermal regime of the Yangtze area is characterized by high in the northeast, low in the middle and localized high again in the southwest, and this pattern is well consistent with the tectono-thermal processes occurred in the area. Due to Cenozoic crustal extension in the northeastern Yangtze area, magmatism is prevailed, accounting for the high heat flow observed. Precambrian basement exists in the middle Yangtze area, such as the Xuefeng and Wuling Mountains, heat flow and subsurface temperature accordingly show relatively low as well. While for the southwestern Yangtze area, especially Yunnan and western Sichuan provinces, localized Cenozoic magmatism and tectonic activities are available, which is attributed to the high geothermal regime there. Considering the Paleozoic intensive tectonic deformation in the Yangtze area, tectonically stable area is prerequisite for shale gas preservation. Geothermal regime analysis

Monitoring of high temperature area by resistivity tomography during in-situ heating test in sedimentary soft rocks

International Nuclear Information System (INIS)

Kubota, Kenji; Suzuki, Koichi; Ikenoya, Takafumi; Takakura, Nozomu; Tani, Kazuo

2009-01-01

One of the major issues in disposal of nuclear waste is that the long term behaviors of sedimentary soft rocks can be affected by various environmental factors such as temperature, mechanical conditions or hydraulic conditions. Therefore, it is necessary to develop a method for evaluating the long term stability of caverns in sedimentary soft rocks as subjected to changes of environment. We have conducted in-situ heating test to evaluate the influence of high temperature to the surrounding rock mass at a depth of 50 m. The well with a diameter of 30 cm and 60 cm of height, was drilled and filled with groundwater. The heater was installed in the well for heating the surrounding rock mass. During the heating, temperature and deformation around the well were measured. To evaluate the influence of heating on sedimentary soft rocks, it is important to monitor the extent of heated area. Resistivity monitoring is thought to be effective to map the extent of the high temperature area. So we have conducted resistivity tomography during the heating test. The results demonstrated that the resistivity of the rock mass around the heating well decreased and this area was gradually expanded from the heated area during the heating. The decreasing rate of resistivity on temperature is correlated to that of laboratory experimental result and existing empirical formula between aqueous solution resistivity and temperature. Resistivity is changed by many other factors, but it is expected that resistivity change by other factors is very few in this test. This suggests that high temperature area is detected and spatial distribution of temperature can be mapped by resistivity tomography. So resistivity tomography is expected to be one of the promising methods to monitor the area heated by nuclear waste. (author)

Temperature variations of average o-Ps lifetime in porous media

CERN Document Server

Goworek, T; Jasinska, B; Wawryszczuk, J

2000-01-01

Modification of the Tao-Eldrup model is proposed in order to extend its usefulness to the case of porous media. The modification consists in the transition from spherical to capillary geometry and in inclusion of pick-off annihilation from the excited states of a particle in the well. Approximated equations for pick-off constant in these states are given. The model was tested by observing the temperature dependences of o-Ps lifetime in various media. In the case of silica gels and Vycor glass with narrow pores, the model seems to work well, while for larger pores in Vycor unexpectedly long lifetimes appear in the range of lowest temperatures.

Spatial Characteristics of Geothermal Spring Temperatures and Discharge Rates in the Tatun Volcanic Area, Taiwan

Science.gov (United States)

Jang, C. S.; Liu, C. W.

2014-12-01

The Tatun volcanic area is the only potential volcanic geothermal region in the Taiwan island, and abundant in hot spring resources owing to stream water mixing with fumarolic gases. According to the Meinzer's classification, spring temperatures and discharge rates are the most important properties for characterizing spring classifications. This study attempted to spatially characterize spring temperatures and discharge rates in the Tatun volcanic area, Taiwanusing indicator kriging (IK). First, data on spring temperatures and discharge rates, which were collected from surveyed data of the Taipei City Government, were divided into high, moderate and low categories according to spring classification criteria, and the various categories were regarded as estimation thresholds. Then, IK was adopted to model occurrence probabilities of specified temperatures and discharge rates in springs, and to determine their classifications based on estimated probabilities. Finally, nine combinations were obtained from the classifications of temperatures and discharge rates in springs. Moreover, the combinations and features of spring water were spatially quantified according to seven sub-zones of spring utilization. A suitable and sustainable development strategy of the spring area was proposed in each sub-zone based on probability-based combinations and features of spring water.The research results reveal that the probability-based classifications using IK provide an excellent insight in exploring the uncertainty of spatial features in springs, and can provide Taiwanese government administrators with detailed information on sustainable spring utilization and conservation in the overexploited spring tourism areas. The sub-zones BT (Beitou), RXY (Rd. Xingyi), ZSL (Zhongshanlou) and LSK (Lengshuikeng) with high or moderate discharge rates are suitable to supply spring water for tourism hotels.Local natural hot springs should be planned in the sub-zones DBT (Dingbeitou), ZSL, XYK

Calculation of climate factors as an additional criteria to determine agriculturally less favoured areas

Directory of Open Access Journals (Sweden)

Tjaša POGAČAR

2016-04-01

Full Text Available Climate factors that are proposed to determine agriculturally less favoured areas (LFA in Slovenia were analyzed for the period 1981–2010. Following the instructions of European Commission prepared by Joint Research Centre (JRC 30-years averages of low air temperatures criteria (the vegetation period duration and sums of effective air temperatures and aridity criteria (aridity index AI have to be calculated. Calculations were additionally done using Slovenian Environment Agency (ARSO method, which is slightly different when determining temperature thresholds. Only hilly areas are below the LFA low air temperatures threshold with the lowest located meteorological station in Rateče. According to aridity criteria no area in Slovenia is below the threshold, so meteorological water balance was also examined. Average water balance in the period 1981–2010 was in most of locations lower than in the period 1971–2000. Climate change impacts are already expressed as trend presence in time series of studied variables, so it is recommended to calculate trends and take them into account or to perform regular iterations of calculations.

Fundamental research in the area of high temperature fuel cells in Russia

Energy Technology Data Exchange (ETDEWEB)

Dyomin, A.K.

1996-04-01

Research in the area of molten carbonate and solid oxide fuel cells has been conducted in Russia since the late 60`s. Institute of High Temperature Electrochemistry is the lead organisation in this area. Research in the area of materials used in fuel cells has allowed us to identify compositions of electrolytes, electrodes, current paths and transmitting, sealing and structural materials appropriate for long-term fuel cell applications. Studies of electrode processes resulted in better understanding of basic patterns of electrode reactions and in the development of a foundation for electrode structure optimization. We have developed methods to increase electrode activity levels that allowed us to reach current density levels of up to 1 amper/cm{sup 2}. Development of mathematical models of processes in high temperature fuel cells has allowed us to optimize their structure. The results of fundamental studies have been tested on laboratory mockups. MCFC mockups with up to 100 W capacity and SOFC mockups with up to 1 kW capacity have been manufactured and tested at IHTE. There are three SOFC structural options: tube, plate and modular.

Nanoparticle manipulation in the near-substrate areas of low-temperature, high-density rf plasmas

International Nuclear Information System (INIS)

Rutkevych, P.P.; Ostrikov, K.; Xu, S.

2005-01-01

Manipulation of a single nanoparticle in the near-substrate areas of high-density plasmas of low-temperature glow discharges is studied. It is shown that the nanoparticles can be efficiently manipulated by the thermophoretic force controlled by external heating of the substrate stage. Particle deposition onto or repulsion from nanostructured carbon surfaces critically depends on the values of the neutral gas temperature gradient in the near-substrate areas, which is directly measured in situ in different heating regimes by originally developed temperature gradient probe. The measured values of the near-surface temperature gradient are used in the numerical model of nanoparticle dynamics in a variable-length presheath. Specific conditions enabling the nanoparticle to overcome the repulsive potential and deposit on the substrate during the discharge operation are investigated. The results are relevant to fabrication of various nanostructured films employing structural incorporation of the plasma-grown nanoparticles, in particular, to nanoparticle deposition in the plasma-enhanced chemical-vapor deposition of carbon nanostructures in hydrocarbon-based plasmas

Comparison Between AQUARIUS and SMOS brightness temperatures for Heterogeneous Land Areas

Science.gov (United States)

Benlloch, Amparo; Lopez-Baeza, Ernesto; Tenjo, Carolina; Navarro, Enrique

2016-07-01

Intercomparison between Aquarius and SMOS brightness temperatures (TBs) over land surfaces is more challenging than over oceans because land footprints are more heterogeneous. In this work we are comparing Aquarius and SMOS TBs under coherente conditions obtained both by considering similar areas, according to land uses and by stratifying by means of TVDI (Temperature Vegetation Dryness Index) that accounts for the dynamics of the vegetation instead of assuming static characteristics as in the previous approches. The area of study was chosen in central Spain where we could get a significant number of matches between both instruments. The study period corresponded to 2012-2014. SMOS level-3 data were obtained from the Centre Aval de Traitement des Données SMOS (CATDS) and Aquarius' from the Physical Oceanography Distributed Active Archive Center (PODAAC). Land uses were obtained from the Spanish SIOSE facility (Sistema de Informacion de Ocupacion del Suelo en España) that uses a scale of 1:25.000 and polygon geometrical structure layer. SIOSE is based on panchromatic and multispectral 2.5 m resolution SPOT-5 images together with Landsat-5 images and orthophotos from the Spanish Nacional Plan of Aerial Orthophotography (PNOA). TVDI values were obtained from MODIS operational products of land surface temperature and NDVI. SMOS ascending TBs were compared to inner-beam Aquarius descending half-orbit TBs coinciding over the study area at 06:00 h. The Aquarius inner beam has an incidence angle of 28,7º and SMOS data were considered for the 27,5º incidence angle. The SMOS products corresponded to version 2.6x (data before 31st Oct 2013) and version 2.7x (data after 1st Jan 2014). Intersections between both footprints were analysed under conditions of similar areas, land uses and TVDI values. For the latter (land uses/TVDI), a linear combination of SMOS land uses/TVDI was obtained to match the larger Aquarius footprint. A more physical approach is also under way

Increase in average foveal thickness after internal limiting membrane peeling

Directory of Open Access Journals (Sweden)

Kumagai K

2017-04-01

Full Text Available Kazuyuki Kumagai,1 Mariko Furukawa,1 Tetsuyuki Suetsugu,1 Nobuchika Ogino2 1Department of Ophthalmology, Kami-iida Daiichi General Hospital, 2Department of Ophthalmology, Nishigaki Eye Clinic, Aichi, Japan Purpose: To report the findings in three cases in which the average foveal thickness was increased after a thin epiretinal membrane (ERM was removed by vitrectomy with internal limiting membrane (ILM peeling.Methods: The foveal contour was normal preoperatively in all eyes. All cases underwent successful phacovitrectomy with ILM peeling for a thin ERM. The optical coherence tomography (OCT images were examined before and after the surgery. The changes in the average foveal (1 mm thickness and the foveal areas within 500 µm from the foveal center were measured. The postoperative changes in the inner and outer retinal areas determined from the cross-sectional OCT images were analyzed.Results: The average foveal thickness and the inner and outer foveal areas increased significantly after the surgery in each of the three cases. The percentage increase in the average foveal thickness relative to the baseline thickness was 26% in Case 1, 29% in Case 2, and 31% in Case 3. The percentage increase in the foveal inner retinal area was 71% in Case 1, 113% in Case 2, and 110% in Case 3, and the percentage increase in foveal outer retinal area was 8% in Case 1, 13% in Case 2, and 18% in Case 3.Conclusion: The increase in the average foveal thickness and the inner and outer foveal areas suggests that a centripetal movement of the inner and outer retinal layers toward the foveal center probably occurred due to the ILM peeling. Keywords: internal limiting membrane, optical coherence tomography, average foveal thickness, epiretinal membrane, vitrectomy

Climatic change in Mediterranean area

International Nuclear Information System (INIS)

Manos, A.

1991-01-01

United Nations Environmental Program (UNEP) studies on forecasted greenhouse climatic effects on the Mediterranean coastal and marine ecosystems and regional socio-economic framework have indicated the need for a concerted plan of protective and remedial action. The studies considered rises of 1.5 degrees in ambient temperature and 20 centimeters in sea level occurring before the year 2025. A regional, as opposed to a global area, study approach was adopted since the severity of climatic effects is expected to vary greatly from one part of the world to another. The specific areas investigated were the Po River Delta and Venezia Lagoon in Italy, the Nile Delta, Camargue, the Ebro Delta, the Tunisian National Park area, and the Thermaicos Gulf in Greece. The rise in average temperature is expected to negatively effect Mediterranean agricultural production and the coastal and marine ecosystems due to prolonged periods of drought and exceptional rainfall. It is suggested that a system of dikes be constructed to protect the coastal areas which are heavily dependent on tourism and agriculture

Analysis of the Slab Temperature, Thermal Stresses and Fractures Computed with the Implementation of Local and Average Boundary Conditions in the Secondary Cooling Zones

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Hadała B.

2016-12-01

Full Text Available The numerical simulations of the temperature fields have been accomplished for slab casting made of a low carbon steel. The casting process of slab of 1500 mm in width and 225 mm in height has been modeled. Two types of boundary condition models of heat transfer have been employed in numerical simulations. The heat transfer coefficient in the first boundary condition model was calculated from the formula which takes into account the slab surface temperature and water flow rate in each secondary cooling zone. The second boundary condition model defines the heat transfer coefficient around each water spray nozzle. The temperature fields resulting from the average in zones water flow rate and from the nozzles arrangement have been compared. The thermal stresses and deformations resulted from such temperature field have given higher values of fracture criterion at slab corners.

Long-term patterns of air temperatures, daily temperature range, precipitation, grass-reference evapotranspiration and aridity index in the USA Great Plains: Part I. Spatial trends

Science.gov (United States)

Kukal, M.; Irmak, S.

2016-11-01

Due to their substantial spatio-temporal behavior, long-term quantification and analyses of important hydrological variables are essential for practical applications in water resources planning, evaluating the water use of agricultural crop production and quantifying crop evapotranspiration patterns and irrigation management vs. hydrologic balance relationships. Observed data at over 800 sites across the Great Plains of USA, comprising of 9 states and 2,307,410 km2 of surface area, which is about 30% of the terrestrial area of the USA, were used to quantify and map large-scale and long-term (1968-2013) spatial trends of air temperatures, daily temperature range (DTR), precipitation, grass-reference evapotranspiration (ETo) and aridity index (AI) at monthly, growing season and annual time steps. Air temperatures had a strong north to south increasing trend, with annual average varying from -1 to 24 °C, and growing season average temperature varying from 8 to 30 °C. DTR gradually decreased from western to eastern parts of the region, with a regional annual and growing season averages of 14.25 °C and 14.79 °C, respectively. Precipitation had a gradual shift towards higher magnitudes from west to east, with the average annual and growing season (May-September) precipitation ranging from 163 to 1486 mm and from 98 to 746 mm, respectively. ETo had a southwest-northeast decreasing trend, with regional annual and growing season averages of 1297 mm and 823 mm, respectively. AI increased from west to east, indicating higher humidity (less arid) towards the east, with regional annual and growing season averages of 0.49 and 0.44, respectively. The spatial datasets and maps for these important climate variables can serve as valuable background for climate change and hydrologic studies in the Great Plains region. Through identification of priority areas from the developed maps, efforts of the concerned personnel and agencies and resources can be diverted towards development

Thermal effects in high average power optical parametric amplifiers.

Science.gov (United States)

Rothhardt, Jan; Demmler, Stefan; Hädrich, Steffen; Peschel, Thomas; Limpert, Jens; Tünnermann, Andreas

2013-03-01

Optical parametric amplifiers (OPAs) have the reputation of being average power scalable due to the instantaneous nature of the parametric process (zero quantum defect). This Letter reveals serious challenges originating from thermal load in the nonlinear crystal caused by absorption. We investigate these thermal effects in high average power OPAs based on beta barium borate. Absorption of both pump and idler waves is identified to contribute significantly to heating of the nonlinear crystal. A temperature increase of up to 148 K with respect to the environment is observed and mechanical tensile stress up to 40 MPa is found, indicating a high risk of crystal fracture under such conditions. By restricting the idler to a wavelength range far from absorption bands and removing the crystal coating we reduce the peak temperature and the resulting temperature gradient significantly. Guidelines for further power scaling of OPAs and other nonlinear devices are given.

Preparation of lanthanum ferrite powder at low temperature

Energy Technology Data Exchange (ETDEWEB)

Andoulsi, R.; Horchani-Naifer, K.; Ferid, M., E-mail: karima_horchani@yahoo.com [Physical Chemistry Laboratory of Mineral Materials and their Applications, Hammam-Lif (Tunisia)

2012-01-15

Single lanthanum ferrite phase was successfully prepared at low processing temperature using the polymerizable complex method. To implement this work, several techniques such as differential scanning calorimetry, X-ray diffraction, Fourier Transform Infrared Spectroscopy, scanning electron microscopy and BET surface area measurements were used. Throw the obtained results, it was shown that steps of preparing the powder precursor and temperature of its calcination are critical parameters for avoiding phase segregation and obtaining pure lanthanum ferrite compound. Thus, a single perovskite phase was obtained at 600 deg C. At this temperature, the powder was found to be fine and homogeneous with an average crystallite size of 13 nm and a specific surface area of 12.5 m{sup 2}.g{sup -1}. (author)

Temperature dependence of the effective sensing area of high-Tc dc SQUIDs

International Nuclear Information System (INIS)

Brake, H.J.M. ter; Aarnink, W.A.M.; Bosch, P.J. van den; Hilgenkamp, J.W.M.; Flokstra, J.; Rogalla, H.

1997-01-01

The effective sensing area of a high-T c dc SQUID depends on temperature. As a consequence, fluctuations in the operating temperature result in apparent magnetic field noise if the SQUID is placed in a background magnetic field. An analysis of this effect for two SQUID types, the square-washer 'Ketchen' type and the inductively shunted type, is performed. For magnetocardiography, the temperature fluctuations (peak to peak) of the latter SQUID type should be below w 0.3 mK at 77 K, and below 2 mK at 55 K, with an earth's field suppression of 40 dB. For the square-washer SQUID the requirements are about 8 times less stringent. (author)

Forecast of sea surface temperature off the Peruvian coast using an autoregressive integrated moving average model

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Carlos Quispe

2013-04-01

Full Text Available El Niño connects globally climate, ecosystems and socio-economic activities. Since 1980 this event has been tried to be predicted, but until now the statistical and dynamical models are insuffi cient. Thus, the objective of the present work was to explore using an autoregressive moving average model the effect of El Niño over the sea surface temperature (TSM off the Peruvian coast. The work involved 5 stages: identifi cation, estimation, diagnostic checking, forecasting and validation. Simple and partial autocorrelation functions (FAC and FACP were used to identify and reformulate the orders of the model parameters, as well as Akaike information criterium (AIC and Schwarz criterium (SC for the selection of the best models during the diagnostic checking. Among the main results the models ARIMA(12,0,11 were proposed, which simulated monthly conditions in agreement with the observed conditions off the Peruvian coast: cold conditions at the end of 2004, and neutral conditions at the beginning of 2005.

Lower air temperature is associated with ambulance transports and death in Takamatsu area, Japan.

Science.gov (United States)

Mochimasu, Kazumi Dokai; Miyatake, Nobuyuki; Tanaka, Naoko; Kinoshita, Hiroshi

2014-07-01

The aim of this study was to investigate the linkage among ambulance transports, the number of death and air temperature in Takamatsu area, Japan. Monthly data of ambulance transports (total and acute disease) and the number of death from 2004 to 2012 were obtained from Fire Department Service in Takamatsu and Takamatsu city official website, Japan. Climate parameters for required period were also obtained from Japan Meteorological Agency. Population data in Takamatsu area were also used to adjust ambulance transports and the number of death. The linkage among ambulance transports, the number of death and climate parameters was evaluated by ecological analysis. Total ambulance transports (/a hundred thousand people/day) and ambulance transports due to acute disease (/a hundred thousand people/day) were 12.3 ± 0.9 and 6.8 ± 0.7, respectively. The number of death (/a hundred thousand people/day) was 2.5 ± 0.4. By quadratic curve, ambulance transports due to acute disease and the number of death were significantly correlated with the parameters of air temperature. However, the number of death was the highest in January and the lowest in August. Although higher air temperature was only associated with higher ambulance transports, lower air temperature was associated with both higher ambulance transports and the number death in Takamatsu area, Japan.

Different Multifractal Scaling of the 0 cm Average Ground Surface Temperature of Four Representative Weather Stations over China

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Lei Jiang

2013-01-01

Full Text Available The temporal scaling properties of the daily 0 cm average ground surface temperature (AGST records obtained from four selected sites over China are investigated using multifractal detrended fluctuation analysis (MF-DFA method. Results show that the AGST records at all four locations exhibit strong persistence features and different scaling behaviors. The differences of the generalized Hurst exponents are very different for the AGST series of each site reflecting the different scaling behaviors of the fluctuation. Furthermore, the strengths of multifractal spectrum are different for different weather stations and indicate that the multifractal behaviors vary from station to station over China.

Air temperature and humidity diversity in the Hornsund fjord area (Spitsbergen) in the period 1 July 2014 - 30 June 2015

Science.gov (United States)

Przybylak, Rajmund; Araźny, Andrzej; Wyszyński, Przemysław; Budzik, Tomasz; Wawrzyniak, Tomasz

2016-04-01

The article presents preliminary results of studies into the spatial diversity of air temperature and relative humidity (overground layer, 2 m a.g.l.) in the area of the Hornsund fjord (S Spitsbergen, approx. 77°N), based on data collected between 1 July 2014 and 30 June 2015. The Hornsund fjord runs latitudinal along approx. 40 km and its average width is about 10 km. Numerous glaciers flow into the fjord and the mountain ridges around it often exceed 700 m a.s.l. Data series obtained from 11 sites equipped with automatic weather stations (Vaisala, Campbell, Davis) or HOBO temperature and humidity sensors were used. Two sites (Hornsund HOR and the Hans Glacier HG4) have been operating for years, whereas 9 new ones (Bogstranda BOG, Fugleberget FUG, Gnålodden GNA, Gåshamnoyra GAS, Hyttevika HYT, Lisbetdalen LIS, Ostrogradskijfjella OST, Treskelodden TRE and Wilczekodden WIL) were established within the Polish-Norwegian AWAKE-2 project. Three of the sites (BOG, GAS and OST) were damaged by polar bears, hence their measurement series are shorter. A substantial spatial diversity was found in the air temperature and relative humidity in the area, mostly influenced by elevation, type of surface and distance from the Greenland Sea's open water. During the year (July 2014 - June 2015), the areas of HYT (-1.1°C) and WIL (-1.9°C) were the warmest. Both sites are located on the west coast of the fjord. The HYT demonstrates the most favourable temperature conditions, being orographically sheltered from the east and its cold and dry air masses. The coldest sites were the mountain-top site of FUG (-5.9°C) and the glacier-located HG4 (-4.3°C). The low temperature at FUG resulted from its elevation (568 m a.s.l.), whereas at HG4 (184 m a.s.l) the glaciated surface also added up to the result. In the analysed period, the annual course of air temperature in the area had a clear minimum in February, when the lowest mean monthly values ranged from -9.4°C at HYT to -15.1°C at

Primary collector wall local temperature fluctuations in the area of water-steam phase boundary

Energy Technology Data Exchange (ETDEWEB)

Matal, O.; Klinga, J.; Simo, T. [Energovyzkum Ltd., Brno (Switzerland)

1995-12-31

A limited number of temperature sensors could be installed at the primary collector surface in the area of water - steam phase boundary. The surface temperatures as well WWER 440 steam generator process data were measured and stored for a long time and off-line evaluated. Selected results are presented in the paper. (orig.). 2 refs.

Primary collector wall local temperature fluctuations in the area of water-steam phase boundary

Energy Technology Data Exchange (ETDEWEB)

Matal, O; Klinga, J; Simo, T [Energovyzkum Ltd., Brno (Switzerland)

1996-12-31

A limited number of temperature sensors could be installed at the primary collector surface in the area of water - steam phase boundary. The surface temperatures as well WWER 440 steam generator process data were measured and stored for a long time and off-line evaluated. Selected results are presented in the paper. (orig.). 2 refs.

High average-power induction linacs

International Nuclear Information System (INIS)

Prono, D.S.; Barrett, D.; Bowles, E.

1989-01-01

Induction linear accelerators (LIAs) are inherently capable of accelerating several thousand amperes of /approximately/ 50-ns duration pulses to > 100 MeV. In this paper we report progress and status in the areas of duty factor and stray power management. These technologies are vital if LIAs are to attain high average power operation. 13 figs

Sensitivity of regional climate to global temperature and forcing

International Nuclear Information System (INIS)

Tebaldi, Claudia; O’Neill, Brian; Lamarque, Jean-François

2015-01-01

The sensitivity of regional climate to global average radiative forcing and temperature change is important for setting global climate policy targets and designing scenarios. Setting effective policy targets requires an understanding of the consequences exceeding them, even by small amounts, and the effective design of sets of scenarios requires the knowledge of how different emissions, concentrations, or forcing need to be in order to produce substantial differences in climate outcomes. Using an extensive database of climate model simulations, we quantify how differences in global average quantities relate to differences in both the spatial extent and magnitude of climate outcomes at regional (250–1250 km) scales. We show that differences of about 0.3 °C in global average temperature are required to generate statistically significant changes in regional annual average temperature over more than half of the Earth’s land surface. A global difference of 0.8 °C is necessary to produce regional warming over half the land surface that is not only significant but reaches at least 1 °C. As much as 2.5 to 3 °C is required for a statistically significant change in regional annual average precipitation that is equally pervasive. Global average temperature change provides a better metric than radiative forcing for indicating differences in regional climate outcomes due to the path dependency of the effects of radiative forcing. For example, a difference in radiative forcing of 0.5 W m −2 can produce statistically significant differences in regional temperature over an area that ranges between 30% and 85% of the land surface, depending on the forcing pathway. (letter)

Tear-Film Evaporation Rate from Simultaneous Ocular-Surface Temperature and Tear-Breakup Area.

Science.gov (United States)

Dursch, Thomas J; Li, Wing; Taraz, Baseem; Lin, Meng C; Radke, Clayton J

2018-01-01

A corneal heat-transfer model is presented to quantify simultaneous measurements of fluorescein tear-breakup area (TBA) and ocular-surface temperature (OST). By accounting for disruption of the tear-film lipid layer (TFLL), we report evaporation rates through lipid-covered tear. The modified heat-transfer model provides new insights into evaporative dry eye. A quantitative analysis is presented to assess human aqueous tear evaporation rate (TER) through intact TFLLs from simultaneous in vivo measurement of time-dependent infrared OST and fluorescein TBA. We interpret simultaneous OST and TBA measurements using an extended heat-transfer model. We hypothesize that TBAs are ineffectively insulated by the TFLL and therefore exhibit higher TER than does that for a well-insulting TFLL-covered tear. As time proceeds, TBAs increase in number and size, thereby increasing the cornea area-averaged TER and decreasing OST. Tear-breakup areas were assessed from image analysis of fluorescein tear-film-breakup video recordings and are included in the heat-transfer description of OST. Model-predicted OSTs agree well with clinical experiments. Percent reductions in TER of lipid-covered tear range from 50 to 95% of that for pure water, in good agreement with literature. The physical picture of noninsulating or ruptured TFLL spots followed by enhanced evaporation from underlying cooler tear-film ruptures is consistent with the evaporative-driven mechanism for local tear rupture. A quantitative analysis is presented of in vivo TER from simultaneous clinical measurement of transient OST and TBA. The new heat-transfer model accounts for increased TER through expanding TBAs. Tear evaporation rate varies strongly across the cornea because lipid is effectively missing over tear-rupture troughs. The result is local faster evaporation compared with nonruptured, thick lipid-covered tear. Evaporative-driven tear-film ruptures deepen to a thickness where fluorescein quenching commences and local

Effects of solar activity and galactic cosmic ray cycles on the modulation of the annual average temperature at two sites in southern Brazil

Science.gov (United States)

Frigo, Everton; Antonelli, Francesco; da Silva, Djeniffer S. S.; Lima, Pedro C. M.; Pacca, Igor I. G.; Bageston, José V.

2018-04-01

Quasi-periodic variations in solar activity and galactic cosmic rays (GCRs) on decadal and bidecadal timescales have been suggested as a climate forcing mechanism for many regions on Earth. One of these regions is southern Brazil, where the lowest values during the last century were observed for the total geomagnetic field intensity at the Earth's surface. These low values are due to the passage of the center of the South Atlantic Magnetic Anomaly (SAMA), which crosses the Brazilian territory from east to west following a latitude of ˜ 26°. In areas with low geomagnetic intensity, such as the SAMA, the incidence of GCRs is increased. Consequently, possible climatic effects related to the GCRs tend to be maximized in this region. In this work, we investigate the relationship between the ˜ 11-year and ˜ 22-year cycles that are related to solar activity and GCRs and the annual average temperature recorded between 1936 and 2014 at two weather stations, both located near a latitude of 26° S but at different longitudes. The first of these stations (Torres - TOR) is located in the coastal region, and the other (Iraí - IRA) is located in the interior, around 450 km from the Atlantic Ocean. Sunspot data and the solar modulation potential for cosmic rays were used as proxies for the solar activity and the GCRs, respectively. Our investigation of the influence of decadal and bidecadal cycles in temperature data was carried out using the wavelet transform coherence (WTC) spectrum. The results indicate that periodicities of 11 years may have continuously modulated the climate at TOR via a nonlinear mechanism, while at IRA, the effects of this 11-year modulation period were intermittent. Four temperature maxima, separated by around 20 years, were detected in the same years at both weather stations. These temperature maxima are almost coincident with the maxima of the odd solar cycles. Furthermore, these maxima occur after transitions from even to odd solar cycles, that is

Thermal inertia and radiating average Temperature. A brief analysis of some causes of discomfort; Inercia Termica y Temperatura media radiante. Un breve analisis de algunas causas de disconfort

Energy Technology Data Exchange (ETDEWEB)

Arroba, M.

2008-07-01

Radiant average temperature in walls is as important as dry air temperature to achieve thermal comfort of users of a local. An excessive discrepancy between these levels, or an asymmetric distribution of the surface temperature of fences, may cause localized thermal discomfort, an effect impossible to compensate by rising dry air temperature. Thermal inertia and its concentration must be properly studied in order to handle this parameters, inside or outside the building, on both sides of the cladding or none depending on the weather, the bio climatic strategies used, heating and air conditioning systems and planned use of the building. (Author)

High average-power induction linacs

International Nuclear Information System (INIS)

Prono, D.S.; Barrett, D.; Bowles, E.; Caporaso, G.J.; Chen, Yu-Jiuan; Clark, J.C.; Coffield, F.; Newton, M.A.; Nexsen, W.; Ravenscroft, D.; Turner, W.C.; Watson, J.A.

1989-01-01

Induction linear accelerators (LIAs) are inherently capable of accelerating several thousand amperes of ∼ 50-ns duration pulses to > 100 MeV. In this paper the authors report progress and status in the areas of duty factor and stray power management. These technologies are vital if LIAs are to attain high average power operation. 13 figs

Analysis of heterogeneous characteristics in a geothermal area with low permeability and high temperature

Directory of Open Access Journals (Sweden)

Alfonso Aragón-Aguilar

2017-09-01

Full Text Available An analytical methodology for reservoir characterization was applied in the central and southwestern zones of Los Humeros geothermal field (LHGF. This study involves analysis of temperature, pressure, enthalpy and permeability in wells and their distribution along the area. The wells located in the central western side of the geothermal field are productive, whereas those located at the central-eastern side are non-productive. Through temperature profiles, determined at steady state in the analyzed wells, it was observed that at bottom conditions (approximately 2300 m depth, temperatures vary between 280 and 360 °C. The temperatures are higher at the eastern side of central zone of LHGF. A review of transient pressure tests, laboratory measurements of core samples, and correlation of circulation losses during drilling suggest that permeability of the formation is low. The enthalpy behavior in productive wells shows a tendency of increase in the steam fraction. It was found that productivity behavior has inverse relation with permeability of rock formation. Further, it is observed that an imbalance exists between exploitation and recharge. It is concluded from the results that the wells located at central-eastern area have low permeability and high temperature, which indicates possibility of heat storage.

TEMPERATURE MAPPING OF PETRA CHRISTIAN UNIVERSITY MAIN CAMPUS SURABAYA

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JUNIWATI Anik

2015-07-01

Full Text Available Petra Christian University (PCU is a university in Siwalankerto, a suburban area of Surabaya city, East Java-Indonesia. It is well developed at Siwalankerto that has been crowded with surrounding buildings. This research objective is to find the temperature mapping of PCU. The method is used by calculating all the land coverings including the built areas, the pavements, the green areas, mapped by the Screening Tool for Estate Environment Evaluation software-STEVE tool. The field measurement was also conducted. The results then be analyzed, which lands cover that gives more impact to the ambient air temperature. The climate components reviewed are the minimum, the average and the maximum ambient air temperature in degree Celcius. This research found that the lowest ambient air temperature mapped both by field measurement and STEVE-tool is the Zone 5; while the highest ambient air temperature of the STEVE-tool is the Zone 4; but from the field measurement found that the hottest is the Zone 3. This different results give an input for later STEVE-tool improvement.

Evaluation of yield and identifying potential regions for Saffron (Crocus sativus L. cultivation in Khorasan Razavi province according to temperature parameters

Directory of Open Access Journals (Sweden)

Moein Tosan

2015-04-01

Full Text Available Saffron is cultivated in most part of Iran, because of low water requirement and well adaptation to diverse environmental condition. In recent years, for many reasons such as low water requirement, saffron cultivation areas has been increased especially in Khorasan Razavi province. Temperature is one of the most important factors in saffron flowering phenomena. The aim of this research was to evaluate the response of saffron to temperature in Khorasan Razavi province counties (Torbat-e-Heydarieh, Gonabad, Nishabour, Sabzevar and Ghoochan. Climatic data (monthly minimum, average, maximum temperatures and diurnal temperature range and saffron yield data were collected for past 20 years period. The stepwise regression methods were used to remove extra parameters and only keep the most important ones. By using these equations and ArcGIS software zoning, Spline method was find the best for saffron crop zoning. The results of linear regression in Gonabad showed that minimum, maximum and average temperature and also diurnal temperature range in March and April months had the greatest impact on saffron yield. For each of the four indices (the minimum, maximum and average temperature and also diurnal temperature range the best area for saffron cultivation was the southern part of the province (particularly Gonabad; so by increasing distance from this area to north areas (such as Kashmar, Torbat-e-Heydarieh, Sabzevar, Nishabour, Mashhad and finally Ghoochan saffron yield reduced by 30 to 50 percent. Therefore, the northern areas of the province had relatively low saffron yield. According to result of this research, saffron yield in Khorasan Razavi province was significantly influenced by temperature parameters. Flowering which basically is the most important stage of plant growth, is directly setting up with temperature.

Daily number of fractures is associated with road temperature in an urban area

DEFF Research Database (Denmark)

Jantzen, Christopher; Jørgensen, Henrik L; Thomsen, Morten

2014-01-01

winters. MATERIAL AND METHODS: Retrospective data collection was conducted on all patients treated at Bispebjerg Hospital, Denmark, for a humeral, ankle, distal radius or hip fracture during the periods October to April 2009/2010 and 2010/2011. Patients were grouped according to age into the following......,938 fractures) were treated during the study periods. The daily number of distal radius, humeral and ankle fractures increased significantly with decreasing road surface temperature and the presence of IA. For hip fractures no significant association was found. Decreasing temperature was associated......INTRODUCTION: Different factors related to winter are known to influence the fracture incidence, but little is known about the effect of road surface temperature. This study examines the association between road surface temperature and the daily number of fractures in an urban area during two...

SPATIAL DISTRIBUTION OF THE AVERAGE RUNOFF IN THE IZA AND VIȘEU WATERSHEDS

Directory of Open Access Journals (Sweden)

HORVÁTH CS.

2015-03-01

Full Text Available The average runoff represents the main parameter with which one can best evaluate an area’s water resources and it is also an important characteristic in al river runoff research. In this paper we choose a GIS methodology for assessing the spatial evolution of the average runoff, using validity curves we identifies three validity areas in which the runoff changes differently with altitude. The tree curves were charted using the average runoff values of 16 hydrometric stations from the area, eight in the Vișeu and eight in the Iza river catchment. Identifying the appropriate areas of the obtained correlations curves (between specific average runoff and catchments mean altitude allowed the assessment of potential runoff at catchment level and on altitudinal intervals. By integrating the curves functions in to GIS we created an average runoff map for the area; from which one can easily extract runoff data using GIS spatial analyst functions. The study shows that from the three areas the highest runoff corresponds with the third zone but because it’s small area the water volume is also minor. It is also shown that with the use of the created runoff map we can compute relatively quickly correct runoff values for areas without hydrologic control.

The potential to supply low temperature district heating to existing building area

DEFF Research Database (Denmark)

Li, Hongwei; Svendsen, Svend

2013-01-01

Low-temperature district heating (LTDH) has the advantages as reduced network heat loss, improved quality match between energy supply and energy demand, and increased utilization of low-grade waste heat and renewable energy. The LTDH represents the next generation district heating (DH) system...... to supply existing building areas which are characterized with high heating demand needs to be examined. In this paper, the DH network deliverable capacity to supply LTDH to an existing building area is studied based on building thermal performance and DH network hydraulic performance simulation....

Radiative forcing and temperature response to changes in urban albedos and associated CO2 offsets

International Nuclear Information System (INIS)

Menon, Surabi; Akbari, Hashem; Sednev, Igor; Levinson, Ronnen; Mahanama, Sarith

2010-01-01

The two main forcings that can counteract to some extent the positive forcings from greenhouse gases from pre-industrial times to present day are the aerosol and related aerosol-cloud forcings, and the radiative response to changes in surface albedo. Here, we quantify the change in radiative forcing and land surface temperature that may be obtained by increasing the albedos of roofs and pavements in urban areas in temperate and tropical regions of the globe by 0.1. Using the catchment land surface model (the land model coupled to the GEOS-5 Atmospheric General Circulation Model), we quantify the change in the total outgoing (outgoing shortwave+longwave) radiation and land surface temperature to a 0.1 increase in urban albedos for all global land areas. The global average increase in the total outgoing radiation was 0.5 W m -2 , and temperature decreased by ∼0.008 K for an average 0.003 increase in surface albedo. These averages represent all global land areas where data were available from the land surface model used and are for the boreal summer (June-July-August). For the continental US the total outgoing radiation increased by 2.3 W m -2 , and land surface temperature decreased by ∼0.03 K for an average 0.01 increase in surface albedo. Based on these forcings, the expected emitted CO 2 offset for a plausible 0.25 and 0.15 increase in albedos of roofs and pavements, respectively, for all global urban areas, was found to be ∼57 Gt CO 2 . A more meaningful evaluation of the impacts of urban albedo increases on global climate and the expected CO 2 offsets would require simulations which better characterize urban surfaces and represent the full annual cycle.

Evaluation of low-temperature geothermal potential in Cache Valley, Utah. Report of investigation No. 174

Energy Technology Data Exchange (ETDEWEB)

de Vries, J.L.

1982-11-01

Field work consisted of locating 90 wells and springs throughout the study area, collecting water samples for later laboratory analyses, and field measurement of pH, temperature, bicarbonate alkalinity, and electrical conductivity. Na/sup +/, K/sup +/, Ca/sup +2/, Mg/sup +2/, SiO/sub 2/, Fe, SO/sub 4//sup -2/, Cl/sup -/, F/sup -/, and total dissolved solids were determined in the laboratory. Temperature profiles were measured in 12 additional, unused walls. Thermal gradients calculated from the profiles were approximately the same as the average for the Basin and Range province, about 35/sup 0/C/km. One well produced a gradient of 297/sup 0/C/km, most probably as a result of a near-surface occurrence of warm water. Possible warm water reservoir temperatures were calculated using both the silica and the Na-K-Ca geothermometers, with the results averaging about 50 to 100/sup 0/C. If mixing calculations were applied, taking into account the temperatures and silica contents of both warm springs or wells and the cold groundwater, reservoir temperatures up to about 200/sup 0/C were indicated. Considering measured surface water temperatures, calculated reservoir temperatures, thermal gradients, and the local geology, most of the Cache Valley, Utah area is unsuited for geothermal development. However, the areas of North Logan, Benson, and Trenton were found to have anomalously warm groundwater in comparison to the background temperature of 13.0/sup 0/C for the study area. The warm water has potential for isolated energy development but is not warm enough for major commercial development.

Effect of tank geometry on its average performance

Science.gov (United States)

Orlov, Aleksey A.; Tsimbalyuk, Alexandr F.; Malyugin, Roman V.; Leontieva, Daria A.; Kotelnikova, Alexandra A.

2018-03-01

The mathematical model of non-stationary filling of vertical submerged tanks with gaseous uranium hexafluoride is presented in the paper. There are calculations of the average productivity, heat exchange area, and filling time of various volumes tanks with smooth inner walls depending on their "height : radius" ratio as well as the average productivity, degree, and filling time of horizontal ribbing tank with volume 6.10-2 m3 with change central hole diameter of the ribs. It has been shown that the growth of "height / radius" ratio in tanks with smooth inner walls up to the limiting values allows significantly increasing tank average productivity and reducing its filling time. Growth of H/R ratio of tank with volume 1.0 m3 to the limiting values (in comparison with the standard tank having H/R equal 3.49) augments tank productivity by 23.5 % and the heat exchange area by 20%. Besides, we have demonstrated that maximum average productivity and a minimum filling time are reached for the tank with volume 6.10-2 m3 having central hole diameter of horizontal ribs 6.4.10-2 m.

Spatial distribution of unspecified chronic kidney disease in El Salvador by crop area cultivated and ambient temperature.

Science.gov (United States)

VanDervort, Darcy R; López, Dina L; Orantes, Carlos M; Rodríguez, David S

2014-04-01

Chronic kidney disease of unknown etiology is occurring in various geographic areas worldwide. Cases lack typical risk factors associated with chronic kidney disease, such as diabetes and hypertension. It is epidemic in El Salvador, Central America, where it is diagnosed with increasing frequency in young, otherwise-healthy male farmworkers. Suspected causes include agrochemical use (especially in sugarcane fields), physical heat stress, and heavy metal exposure. To evaluate the geographic relationship between unspecified chronic kidney disease (unCKD) and nondiabetic chronic renal failure (ndESRD) hospital admissions in El Salvador with the proximity to cultivated crops and ambient temperatures. Data on unCKD and ndESRD were compared with environmental variables, crop area cultivated (indicator of agrochemical use) and high ambient temperatures. Using geographically weighted regression analysis, two model sets were created using reported municipal hospital admission rates are per thousand population for unCKD 2006-2010 and rates of ndESRD 2005-2010 [corrected]. These were assessed against local percent of land cultivated by crop (sugarcane, coffee, corn, cotton, sorghum, and beans) and mean maximum ambient temperature, with Moran's indices determining data clustering. Two-dimensional geographic models illustrated parameter spatial distribution. Bivariate geographically weighted regressions showed statistically significant correlations between percent area of sugarcane, corn, cotton, coffee, and bean cultivation, as well as mean maximum ambient temperature with both unCKD and ndESRD hospital admission rates. Percent area of sugarcane cultivation had greatest statistical weight (p ≤ 0.001; Rp2 = 0.77 for unCKD). The most statistically significant multivariate geographically weighted regression model for unCKD included percent area of sugarcane, cotton and corn cultivation (p ≤ 0.001; Rp2 = 0.80), while, for ndESRD, it included the percent area of sugarcane, corn

Changes in Extremely Hot Summers over the Global Land Area under Various Warming Targets.

Science.gov (United States)

Wang, Lei; Huang, Jianbin; Luo, Yong; Yao, Yao; Zhao, Zongci

2015-01-01

Summer temperature extremes over the global land area were investigated by comparing 26 models of the fifth phase of the Coupled Model Intercomparison Project (CMIP5) with observations from the Goddard Institute for Space Studies (GISS) and the Climate Research Unit (CRU). Monthly data of the observations and models were averaged for each season, and statistics were calculated for individual models before averaging them to obtain ensemble means. The summers with temperature anomalies (relative to 1951-1980) exceeding 3σ (σ is based on the local internal variability) are defined as "extremely hot". The models well reproduced the statistical characteristics evolution, and partly captured the spatial distributions of historical summer temperature extremes. If the global mean temperature increases 2°C relative to the pre-industrial level, "extremely hot" summers are projected to occur over nearly 40% of the land area (multi-model ensemble mean projection). Summers that exceed 5σ warming are projected to occur over approximately 10% of the global land area, which were rarely observed during the reference period. Scenarios reaching warming levels of 3°C to 5°C were also analyzed. After exceeding the 5°C warming target, "extremely hot" summers are projected to occur throughout the entire global land area, and summers that exceed 5σ warming would become common over 70% of the land area. In addition, the areas affected by "extremely hot" summers are expected to rapidly expand by more than 25%/°C as the global mean temperature increases by up to 3°C before slowing to less than 16%/°C as the temperature continues to increase by more than 3°C. The area that experiences summers with warming of 5σ or more above the warming target of 2°C is likely to maintain rapid expansion of greater than 17%/°C. To reduce the impacts and damage from severely hot summers, the global mean temperature increase should remain low.

High Recharge Areas in the Choushui River Alluvial Fan (Taiwan Assessed from Recharge Potential Analysis and Average Storage Variation Indexes

Directory of Open Access Journals (Sweden)

Jui-Pin Tsai

2015-03-01

Full Text Available High recharge areas significantly influence the groundwater quality and quantity in regional groundwater systems. Many studies have applied recharge potential analysis (RPA to estimate groundwater recharge potential (GRP and have delineated high recharge areas based on the estimated GRP. However, most of these studies define the RPA parameters with supposition, and this represents a major source of uncertainty for applying RPA. To objectively define the RPA parameter values without supposition, this study proposes a systematic method based on the theory of parameter identification. A surrogate variable, namely the average storage variation (ASV index, is developed to calibrate the RPA parameters, because of the lack of direct GRP observations. The study results show that the correlations between the ASV indexes and computed GRP values improved from 0.67 before calibration to 0.85 after calibration, thus indicating that the calibrated RPA parameters represent the recharge characteristics of the study area well; these data also highlight how defining the RPA parameters with ASV indexes can help to improve the accuracy. The calibrated RPA parameters were used to estimate the GRP distribution of the study area, and the GRP values were graded into five levels. High and excellent level areas are defined as high recharge areas, which composed 7.92% of the study area. Overall, this study demonstrates that the developed approach can objectively define the RPA parameters and high recharge areas of the Choushui River alluvial fan, and the results should serve as valuable references for the Taiwanese government in their efforts to conserve the groundwater quality and quantity of the study area.

Low Temperature Synthesis of Magnesium Aluminate Spinel

International Nuclear Information System (INIS)

Lebedovskaya, E.G.; Gabelkov, S.V.; Litvinenko, L.M.; Logvinkov, D.S.; Mironova, A.G.; Odejchuk, M.A.; Poltavtsev, N.S.; Tarasov, R.V.

2006-01-01

The low-temperature synthesis of magnesium-aluminum spinel is carried out by a method of thermal decomposition in combined precipitated hydrates. The fine material of magnesium-aluminium spinel with average size of coherent dispersion's area 4...5 nanometers is obtained. Magnesium-aluminum spinel and initial hydrates were investigated by methods of the differential thermal analysis, the x-ray phase analysis and measurements of weight loss during the dehydration and thermal decomposition. It is established that synthesis of magnesium-aluminum spinel occurs at temperature 300 degree C by method of the x-ray phase analysis

Albedo and land surface temperature shift in hydrocarbon seepage potential area, case study in Miri Sarawak Malaysia

International Nuclear Information System (INIS)

Suherman, A; Rahman, M Z A; Busu, I

2014-01-01

The presence of hydrocarbon seepage is generally associated with rock or mineral alteration product exposures, and changes of soil properties which manifest with bare development and stress vegetation. This alters the surface thermodynamic properties, changes the energy balance related to the surface reflection, absorption and emission, and leads to shift in albedo and LST. Those phenomena may provide a guide for seepage detection which can be recognized inexpensively by remote sensing method. District of Miri is used for study area. Available topographic maps of Miri and LANDSAT ETM+ were used for boundary construction and determination albedo and LST. Three land use classification methods, namely fixed, supervised and NDVI base classifications were employed for this study. By the intensive land use classification and corresponding statistical comparison was found a clearly shift on albedo and land surface temperature between internal and external seepage potential area. The shift shows a regular pattern related to vegetation density or NDVI value. In the low vegetation density or low NDVI value, albedo of internal area turned to lower value than external area. Conversely in the high vegetation density or high NDVI value, albedo of internal area turned to higher value than external area. Land surface temperature of internal seepage potential was generally shifted to higher value than external area in all of land use classes. In dense vegetation area tend to shift the temperature more than poor vegetation area

Albedo and land surface temperature shift in hydrocarbon seepage potential area, case study in Miri Sarawak Malaysia

Science.gov (United States)

Suherman, A.; Rahman, M. Z. A.; Busu, I.

2014-02-01

The presence of hydrocarbon seepage is generally associated with rock or mineral alteration product exposures, and changes of soil properties which manifest with bare development and stress vegetation. This alters the surface thermodynamic properties, changes the energy balance related to the surface reflection, absorption and emission, and leads to shift in albedo and LST. Those phenomena may provide a guide for seepage detection which can be recognized inexpensively by remote sensing method. District of Miri is used for study area. Available topographic maps of Miri and LANDSAT ETM+ were used for boundary construction and determination albedo and LST. Three land use classification methods, namely fixed, supervised and NDVI base classifications were employed for this study. By the intensive land use classification and corresponding statistical comparison was found a clearly shift on albedo and land surface temperature between internal and external seepage potential area. The shift shows a regular pattern related to vegetation density or NDVI value. In the low vegetation density or low NDVI value, albedo of internal area turned to lower value than external area. Conversely in the high vegetation density or high NDVI value, albedo of internal area turned to higher value than external area. Land surface temperature of internal seepage potential was generally shifted to higher value than external area in all of land use classes. In dense vegetation area tend to shift the temperature more than poor vegetation area.

Average thermal stress in the Al+SiC composite due to its manufacturing process

International Nuclear Information System (INIS)

Miranda, Carlos A.J.; Libardi, Rosani M.P.; Marcelino, Sergio; Boari, Zoroastro M.

2013-01-01

The numerical analyses framework to obtain the average thermal stress in the Al+SiC Composite due to its manufacturing process is presented along with the obtained results. The mixing of Aluminum and SiC powders is done at elevated temperature and the usage is at room temperature. A thermal stress state arises in the composite due to the different thermal expansion coefficients of the materials. Due to the particles size and randomness in the SiC distribution, some sets of models were analyzed and a statistical procedure used to evaluate the average stress state in the composite. In each model the particles position, form and size are randomly generated considering a volumetric ratio (VR) between 20% and 25%, close to an actual composite. The obtained stress field is represented by a certain number of iso stress curves, each one weighted by the area it represents. Systematically it was investigated the influence of: (a) the material behavior: linear x non-linear; (b) the carbide particles form: circular x quadrilateral; (c) the number of iso stress curves considered in each analysis; and (e) the model size (the number of particles). Each of above analyzed condition produced conclusions to guide the next step. Considering a confidence level of 95%, the average thermal stress value in the studied composite (20% ≤ VR ≤ 25%) is 175 MPa with a standard deviation of 10 MPa. Depending on its usage, this value should be taken into account when evaluating the material strength. (author)

Quicklime (CaO) Stabilization of fine-grained marine sediments in low temperature areas

DEFF Research Database (Denmark)

Skels, Peteris; Ingeman-Nielsen, Thomas; Jørgensen, Anders Stuhr

2011-01-01

This study presents laboratory testing on quicklime (CaO) stabilization of fine-grained marine sediments in low temperature areas. The soil was sampled on the Fossil Plain in Kangerlussuaq, Greenland, and analyzed in the laboratory at Technical University of Denmark (DTU). The optimum CaO content...... curing temperatures, comparing stabilization effectiveness between low and normal soil temperature conditions....... in a soil-CaO mixture was determined using a number of laboratory methods, such as pH test, consistency limit analysis, degree of compaction, and short term California Bearing Ratio (CBR) values. The study also numerically demonstrates a long term strength development of the soil-CaO mixture at 1°C and 10°C...

No-contact method of determining average working-surface temperature of plate-type radiation-absorbing thermal exchange panels of flat solar collectors for heating heat-transfer fluid

International Nuclear Information System (INIS)

Avezova, N.R.; Avezov, R.R.

2015-01-01

A brand new no-contact method of determining the average working-surface temperature of plate-type radiation-absorbing thermal exchange panels (RATEPs) of flat solar collectors (FSCs) for heating a heat-transfer fluid (HTF) is suggested on the basis of the results of thermal tests in full-scale quasistationary conditions. (authors)

Signals of Climate Change in Butterfly Communities in a Mediterranean Protected Area

Science.gov (United States)

Zografou, Konstantina; Kati, Vassiliki; Grill, Andrea; Wilson, Robert J.; Tzirkalli, Elli; Pamperis, Lazaros N.; Halley, John M.

2014-01-01

The European protected-area network will cease to be efficient for biodiversity conservation, particularly in the Mediterranean region, if species are driven out of protected areas by climate warming. Yet, no empirical evidence of how climate change influences ecological communities in Mediterranean nature reserves really exists. Here, we examine long-term (1998–2011/2012) and short-term (2011–2012) changes in the butterfly fauna of Dadia National Park (Greece) by revisiting 21 and 18 transects in 2011 and 2012 respectively, that were initially surveyed in 1998. We evaluate the temperature trend for the study area for a 22-year-period (1990–2012) in which all three butterfly surveys are included. We also assess changes in community composition and species richness in butterfly communities using information on (a) species’ elevational distributions in Greece and (b) Community Temperature Index (calculated from the average temperature of species' geographical ranges in Europe, weighted by species' abundance per transect and year). Despite the protected status of Dadia NP and the subsequent stability of land use regimes, we found a marked change in butterfly community composition over a 13 year period, concomitant with an increase of annual average temperature of 0.95°C. Our analysis gave no evidence of significant year-to-year (2011–2012) variability in butterfly community composition, suggesting that the community composition change we recorded is likely the consequence of long-term environmental change, such as climate warming. We observe an increased abundance of low-elevation species whereas species mainly occurring at higher elevations in the region declined. The Community Temperature Index was found to increase in all habitats except agricultural areas. If equivalent changes occur in other protected areas and taxonomic groups across Mediterranean Europe, new conservation options and approaches for increasing species’ resilience may have to be

Signals of climate change in butterfly communities in a Mediterranean protected area.

Science.gov (United States)

Zografou, Konstantina; Kati, Vassiliki; Grill, Andrea; Wilson, Robert J; Tzirkalli, Elli; Pamperis, Lazaros N; Halley, John M

2014-01-01

The European protected-area network will cease to be efficient for biodiversity conservation, particularly in the Mediterranean region, if species are driven out of protected areas by climate warming. Yet, no empirical evidence of how climate change influences ecological communities in Mediterranean nature reserves really exists. Here, we examine long-term (1998-2011/2012) and short-term (2011-2012) changes in the butterfly fauna of Dadia National Park (Greece) by revisiting 21 and 18 transects in 2011 and 2012 respectively, that were initially surveyed in 1998. We evaluate the temperature trend for the study area for a 22-year-period (1990-2012) in which all three butterfly surveys are included. We also assess changes in community composition and species richness in butterfly communities using information on (a) species' elevational distributions in Greece and (b) Community Temperature Index (calculated from the average temperature of species' geographical ranges in Europe, weighted by species' abundance per transect and year). Despite the protected status of Dadia NP and the subsequent stability of land use regimes, we found a marked change in butterfly community composition over a 13 year period, concomitant with an increase of annual average temperature of 0.95°C. Our analysis gave no evidence of significant year-to-year (2011-2012) variability in butterfly community composition, suggesting that the community composition change we recorded is likely the consequence of long-term environmental change, such as climate warming. We observe an increased abundance of low-elevation species whereas species mainly occurring at higher elevations in the region declined. The Community Temperature Index was found to increase in all habitats except agricultural areas. If equivalent changes occur in other protected areas and taxonomic groups across Mediterranean Europe, new conservation options and approaches for increasing species' resilience may have to be devised.

Signals of climate change in butterfly communities in a Mediterranean protected area.

Directory of Open Access Journals (Sweden)

Konstantina Zografou

Full Text Available The European protected-area network will cease to be efficient for biodiversity conservation, particularly in the Mediterranean region, if species are driven out of protected areas by climate warming. Yet, no empirical evidence of how climate change influences ecological communities in Mediterranean nature reserves really exists. Here, we examine long-term (1998-2011/2012 and short-term (2011-2012 changes in the butterfly fauna of Dadia National Park (Greece by revisiting 21 and 18 transects in 2011 and 2012 respectively, that were initially surveyed in 1998. We evaluate the temperature trend for the study area for a 22-year-period (1990-2012 in which all three butterfly surveys are included. We also assess changes in community composition and species richness in butterfly communities using information on (a species' elevational distributions in Greece and (b Community Temperature Index (calculated from the average temperature of species' geographical ranges in Europe, weighted by species' abundance per transect and year. Despite the protected status of Dadia NP and the subsequent stability of land use regimes, we found a marked change in butterfly community composition over a 13 year period, concomitant with an increase of annual average temperature of 0.95°C. Our analysis gave no evidence of significant year-to-year (2011-2012 variability in butterfly community composition, suggesting that the community composition change we recorded is likely the consequence of long-term environmental change, such as climate warming. We observe an increased abundance of low-elevation species whereas species mainly occurring at higher elevations in the region declined. The Community Temperature Index was found to increase in all habitats except agricultural areas. If equivalent changes occur in other protected areas and taxonomic groups across Mediterranean Europe, new conservation options and approaches for increasing species' resilience may have to be

Geothermic analysis of high temperature hydrothermal activities area in Western plateau of Sichuan province, China

Science.gov (United States)

Zhang, J.

2016-12-01

There is a high temperature hydrothermal activity area in the western plateau of Sichuan. More than 200 hot springs points have been found in the region, including 11 hot spring water temperature above local boiling point. Most of these distribute along Jinshajjiang fracture, Dege-Xiangcheng fracture, Ganzi-Litang fracture as well as Xianshuihe fracture, and form three high-temperature hydrothermal activity strips in the NW-SE direction. Using gravity, magnetic, seismic and helium isotope data, this paper analyzed the crust-mantle heat flow structure, crustal heat source distribution and water heating system. The results show that the geothermal activity mainly controlled by the "hot" crust. The ratio of crustal heat flow and surface heat flow is higher than 60%. In the high temperature hydrothermal activities area, there is lower S wave velocity zone with VsGeothermal water mainly reserve in the Triassic strata of the containing water good carbonate rocks, and in the intrusive granite which is along the fault zone. The thermal energy of Surface heat thermal activities mainly comes from the high-temperature hot source which is located in the middle and lower crust. Being in the deep crustal fracture, the groundwater infiltrated to the deep crust and absorbed heat, then, quickly got back to the surface and formed high hot springs.

The average concentrations of As, Cd, Cr, Hg, Ni and Pb in residential soil and drinking water obtained from springs and wells in Rosia Montana area.

Data.gov (United States)

U.S. Environmental Protection Agency — The average concentrations of As, Cd, Cr, Hg, Ni and Pb in n=84 residential soil samples, in Rosia Montana area, analyzed by X-ray fluorescence spectrometry are...

A temperature and vegetation adjusted NTL urban index for urban area mapping and analysis

Science.gov (United States)

Zhang, Xiya; Li, Peijun

2018-01-01

Accurate and timely information regarding the extent and spatial distribution of urban areas on regional and global scales is crucially important for both scientific and policy-making communities. Stable nighttime light (NTL) data from the Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) provides a unique proxy of human settlement and activity, which has been used in the mapping and analysis of urban areas and urbanization dynamics. However, blooming and saturation effects of DMSP/OLS NTL data are two unresolved problems in regional urban area mapping and analysis. This study proposed a new urban index termed the Temperature and Vegetation Adjusted NTL Urban Index (TVANUI). It is intended to reduce blooming and saturation effects and to enhance urban features by combining DMSP/OLS NTL data with Normalized Difference Vegetation Index (NDVI) and land surface temperature (LST) data from the Moderate Resolution Imaging Spectroradiometer onboard the Terra satellite. The proposed index was evaluated in two study areas by comparison with established urban indices. The results demonstrated the proposed TVANUI was effective in enhancing the variation of DMSP/OLS light in urban areas and in reducing blooming and saturation effects, showing better performance than three established urban indices. The TVANUI also significantly outperformed the established urban indices in urban area mapping using both the global-fixed threshold and the local-optimal threshold methods. Thus, the proposed TVANUI provides a useful variable for urban area mapping and analysis on regional scale, as well as for urbanization dynamics using time-series DMSP/OLS and related satellite data.

Influence of coma aberration on aperture averaged scintillations in oceanic turbulence

Science.gov (United States)

Luo, Yujuan; Ji, Xiaoling; Yu, Hong

2018-01-01

The influence of coma aberration on aperture averaged scintillations in oceanic turbulence is studied in detail by using the numerical simulation method. In general, in weak oceanic turbulence, the aperture averaged scintillation can be effectively suppressed by means of the coma aberration, and the aperture averaged scintillation decreases as the coma aberration coefficient increases. However, in moderate and strong oceanic turbulence the influence of coma aberration on aperture averaged scintillations can be ignored. In addition, the aperture averaged scintillation dominated by salinity-induced turbulence is larger than that dominated by temperature-induced turbulence. In particular, it is shown that for coma-aberrated Gaussian beams, the behavior of aperture averaged scintillation index is quite different from the behavior of point scintillation index, and the aperture averaged scintillation index is more suitable for characterizing scintillations in practice.

Spatial patterns in timing of the diurnal temperature cycle

Directory of Open Access Journals (Sweden)

T. R. H. Holmes

2013-10-01

Full Text Available This paper investigates the structural difference in timing of the diurnal temperature cycle (DTC over land resulting from choice of measuring device or model framework. It is shown that the timing can be reliably estimated from temporally sparse observations acquired from a constellation of low Earth-orbiting satellites given record lengths of at least three months. Based on a year of data, the spatial patterns of mean DTC timing are compared between temperature estimates from microwave Ka-band, geostationary thermal infrared (TIR, and numerical weather prediction model output from the Global Modeling and Assimilation Office (GMAO. It is found that the spatial patterns can be explained by vegetation effects, sensing depth differences and more speculatively the orientation of orographic relief features. In absolute terms, the GMAO model puts the peak of the DTC on average at 12:50 local solar time, 23 min before TIR with a peak temperature at 13:13 (both averaged over Africa and Europe. Since TIR is the shallowest observation of the land surface, this small difference represents a structural error that possibly affects the model's ability to assimilate observations that are closely tied to the DTC. The equivalent average timing for Ka-band is 13:44, which is influenced by the effect of increased sensing depth in desert areas. For non-desert areas, the Ka-band observations lag the TIR observations by only 15 min, which is in agreement with their respective theoretical sensing depth. The results of this comparison provide insights into the structural differences between temperature measurements and models, and can be used as a first step to account for these differences in a coherent way.

Reverse trends of TEX86 temperature in coastal areas of the East China Sea over the last 100 years: implication for global warming and regional circulation

Science.gov (United States)

Cao, Y.; Xing, L.; Zhang, T.

2017-12-01

To reconstruct and compare the SST changes in different regions of the ECS over the last 100 years, in this study, we analyzed iGDGTs compounds and TEX86 index in two sediment cores (DH5-1 and DH6-2) from the inner shelf of the East China Sea (ECS). GDGT-0 and GDGT-5 in the two cores account for 80% of iGDGTs, significantly more abundant than the other iGDGTs compounds. It is also found that iGDGTs are mainly derived from marine Thaumarchaeota. TEXH86 temperatures varied from 17 °C to 22 °C (average 19.4 °C), showing a gradual increase in Core DH5-1 near the Changjiang River Estuary, corresponding to global warming and temperature rise in the ECS over the last 100 years. However, in Core DH6-2 further away from the Changjiang River Estuary, TEXH86 temperatures gradually decreased over the last 80 years with a range of 15.3 °C-18.3 °C, which is attributed to the strengthened near-shore Kuroshio Branch Current transporting more subsurface cold water to the ECS coastal area. In future, more sites should be investigated to confirm the range of the coastal area where the decrease in SST is caused by upwelling subsurface water.

Research for Preseismic Phenomena on the Underground Water Level and Temperature in Selected Areas of Greece

Science.gov (United States)

Contadakis, M. E.; Asteriadis, G.

1997-08-01

A comprehensive study of the tectonic activity require the contribution of a variety of methods, geological, seismic, geodetic, satellite etc., being currently available in our days. On the other hand, the risk evaluation in areas of high seismicity, like this one of the South Balkan Peninsula, is of vital importance. To this purpose an interdisciplinary following up of the tectonic activity in the area may provide the best provision to the administration for an effective confrontation and intervention for the elimination of the possible disastrous effects in human life cost, financial and social cost of the communities, to which may result a strong earthquake. Among the various methods of indirect monitoring of the tectonic activity in an area, which in addition is of a low cost, is that of the following up of the underground water level and temperature changes in the area of interest. This method is based on the fact that tectonic activity is expected to result to tectonic stresses producing alterations to the local water table which in its turn is expected is expected to be observed as variation of the underground water level and temperature. The method of the following up of the underground water and temperature changes has been applied, among others by the Department of Geodesy and Surveying of the University of Thessaloniki in two areas of high seismicity in Greece: (a) The seismic zone of the lake Volvi in North Greece (40.5 deg N and 23.5 deg E) for ten years (1983-1992) and (b) the area of South Thessaly (39.2 deg N and 21 deg E) for three years (1994-1996). The statistical analysis of the observations, shows that the low frequency constituent (Sa,Ssa,Mf,Mm) of the earth tides and the barometric pressure have a small influence on the water level measurements. The shallow underground water network of South Thessaly is more sensitive to the non tectonic factors than the network of Volvi. Tentative correlation of the underground wat! er and temperature

Geothermal data-base study: mine-water temperatures. Final report

Energy Technology Data Exchange (ETDEWEB)

Lawson, D.C.; Sonderegger, J.L.

1978-07-01

Investigation of about 1,600 mines and prospects for perennial discharge resulted in the measurement of temperature, pH, specific conductance, and discharge at 80 sites to provide information for a geothermal data base. Measurements were made in the fall, winter, and late spring or early summer to provide information about seasonal variability. None of the temperatures measured exceeded the mean annual air temperature by 15/sup 0/F, but three areas were noted where discharges were anomalously warm, based upon high temperatures, slight temperature variation, and quantity of discharge. The most promising area, at the Gold Bug mine in the Little Rockies, discharges water averaging 7.3/sup 0/C (12.1/sup 0/F) above the mean annual air temperature. The discharge may represent water heated during circulation within the syenite intrusive body. If the syenite is enriched in uranium and thorium, an abnormal amount of heat would be produced by radioactive decay. Alternatively, the water may move through deep permeable sedimentary strata, such as the Madison Group, and be discharged to the surface through fractures in the pluton.

Is there a relationship between fledge age and nest temperature in Western Bluebirds (Sialia mexicana)?

Energy Technology Data Exchange (ETDEWEB)

Phillips, Emily Marie [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Thompson, Brent E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hathcock, Charles Dean [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-11-30

Extensive research has been done on temperature during bird incubation periods, but little has been done during nestling development, and to our knowledge, no studies have been done on Western Bluebird (Sialia mexicana) nestling development. In this study, dataloggers were used to monitor nest temperatures during the nestling development phase of Western Bluebirds to determine if there was a relationship between fledge age and temperature. The study was conducted in an existing nestbox network at Los Alamos National Laboratory and the surrounding area in north-central New Mexico. Based on the age of the nestlings at fledging, the nestboxes (n=65) were split into three groups: early (16 and 17 days old, n=13), average (fledged at or between 18 and 20 days old, n=32), and late (21 days or older, n=20). The temperatures of the early and average (n=45) groups were not significantly different (p=0.32, W=3831000). There was a significant difference in the temperatures between the early and late groups (p=0.000, W=2965600). The early and average groups were then combined, tested against the late group, and were found to be significantly different (p=0.000, W=11315000). Analysis showed a difference within the first seven days post-hatch of 1.42°C between the early/average and late groupings. The results suggest that warmer nest temperatures during the nestling stage may influence the fledge date and may lead to faster fledging. There may be numerous explanations for this, such as a correlation with nestling development, and higher temperatures may allow for faster development. Brood size was non-significant and was not factored into the analysis. Future work should be directed in this area.

Three exciting areas of experimental physical sciences : high temperature superconductors, metal clusters and super molecules of carbon

International Nuclear Information System (INIS)

Rao, C.N.

1992-01-01

The author has narrated his experience in carrying out research in three exciting areas of physical sciences. These areas are : high temperature superconductors, metal clusters and super molecules of carbon. (M.G.B.)

Comparison of average global exposure of population induced by a macro 3G network in different geographical areas in France and Serbia.

Science.gov (United States)

Huang, Yuanyuan; Varsier, Nadège; Niksic, Stevan; Kocan, Enis; Pejanovic-Djurisic, Milica; Popovic, Milica; Koprivica, Mladen; Neskovic, Aleksandar; Milinkovic, Jelena; Gati, Azeddine; Person, Christian; Wiart, Joe

2016-09-01

This article is the first thorough study of average population exposure to third generation network (3G)-induced electromagnetic fields (EMFs), from both uplink and downlink radio emissions in different countries, geographical areas, and for different wireless device usages. Indeed, previous publications in the framework of exposure to EMFs generally focused on individual exposure coming from either personal devices or base stations. Results, derived from device usage statistics collected in France and Serbia, show a strong heterogeneity of exposure, both in time, that is, the traffic distribution over 24 h was found highly variable, and space, that is, the exposure to 3G networks in France was found to be roughly two times higher than in Serbia. Such heterogeneity is further explained based on real data and network architecture. Among those results, authors show that, contrary to popular belief, exposure to 3G EMFs is dominated by uplink radio emissions, resulting from voice and data traffic, and average population EMF exposure differs from one geographical area to another, as well as from one country to another, due to the different cellular network architectures and variability of mobile usage. Bioelectromagnetics. 37:382-390, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Effect of land area on average annual suburban water demand ...

African Journals Online (AJOL)

AADD) in South Africa are based on residential plot size. This paper presents a novel, robust method for estimating suburban water demand as a function of the suburb area. Seventy suburbs, identified as being predominantly residential, were ...

The investigation of spatiotemporal variations of land surface temperature based on land use changes using NDVI in southwest of Iran

Science.gov (United States)

Fathizad, Hassan; Tazeh, Mahdi; Kalantari, Saeideh; Shojaei, Saeed

2017-10-01

Land use changes can bring about changes in land surface temperature (LST) which is influenced by climatic conditions and physical characteristics of the land surface. In this study, spatiotemporal variations of land surface temperature have been investigated in the desert area of Dasht-e-Abbas, Ilam, based on a variety of land use changes. The investigated periods for the study include 1990, 2000 and 2010 using Landsat image data. First, in mapping land use we used the Fuzzy ARTMAP Neural Network Classification method followed by determination of the NDVI Index to estimate land surface temperature. The results show an increase in LST in areas where degradation, land use and land cover changes have occurred. In 1990, 2000 and 2010, the average land surface temperature of the Fair Rangelands was 26.72 °C, 30.06 °C and 30.95 °C, respectively. This rangeland has been reduced by about 5%. For poor rangelands, the average LSTs were 26.95, 32.83 and 34.49 Cº, respectively which had a 18% reduction. In 1990, 2000 and 2010, the average land surface temperatures of agricultural lands were 24.31 °C, 27.87 °C and 28.61 °C, respectively which has been an increasing trend. The reason can be attributed to changes in cropping patterns of the study area.

Development of an innovative low temperature heat supply concept for a new housing area

OpenAIRE

Schmidt, Dietrich; Kallert, Anna; Orozaliev, Janybek; Best, Isabelle; Vajen, Klaus; Reul, Oliver; Bennewitz, Jochen; Gerhold, Petra

2017-01-01

The domestic energy demand of buildings is responsible for one third of the world's final energy consumption. To increase the sustainability of new housing areas, the identification of innovative heat supply concepts based on renewable energy sources (RES) is required. For the new housing area “Zum Feldlager” (Kassel, Germany), various supply concepts are studied. Main objective is the development of an innovative and efficient supply concept based on RES and low temperature district heating ...

A discussion of non-linear temperature profiles at six closely spaced heat flow sites, southern Sohm Abyssal Plain, northwest Atlantic Ocean

Science.gov (United States)

Burgess, M. M.

1986-09-01

Six heat flow measurement sites were occupied in June 1980 in a 10 x 10 km 2 flat area of the southern Sohm Abyssal Plain, western North Atlantic Ocean. Non-linear sediment temperature profiles, measured to depths of 5 m, indicate perturbations in the temperature field in sediments overlying 90 Ma ocean floor. Temperature gradients average 59.0 mK m -1 in the lower half of the profile and decrease by 25% to an average of 44.24 mK m -1 in the upper half. Thermal conductivities of sediment cores down to 12 m ranged from 0.74 to 2.12 W m -1 K -1 and averaged 1.06 W m -1K -1. The non-linearity of sediment temperature profiles cannot be accounted for by the variations in thermal conductivity. Vertical fluid convection in the sediments, with a predominantly downward migration on the order of 5 x 10 -8 ms -1 in the upper 3 m, could explain the perturbations. However, in this study area of high abyssal kinetic energy and abyssal storms, bottom-water temperature fluctuations are the likely source of observed sediment temperature perturbations. A bottom-water temperature change of 50 mK occurring 3 months prior to the cruise could produce sediment temperature perturbations similar to those observed. Heat flow determined from the lower gradient (3-5 m sediment depth interval), assuming the non-linearity in the upper sensors to be principally due to bottom-water temperature fluctuations, averages 59.2 mW m -2, a slightly higher value than that predicted for 90 Ma crust.

Determination of an optimum reactor coolant system average temperature within the licensed operating window

International Nuclear Information System (INIS)

Thaulez, F.; Basic, I.; Vrbanic, I.

2003-01-01

The Krsko modernization power uprate analyses have been performed in such a way as to cover plant operation in a range of average reactor coolant temperatures (Tavg) of 301.7 deg C to 307.4 deg C, with steam generator tube plugging levels of up to 5%. The upper bound is temporarily restricted to 305.7 deg C, as long as Zirc-4 fuel is present in the core. (It is, however,acceptable to operate at 307.4 deg C with a few Zirc-4 assemblies, if meeting certain conditionsand subjected to a corrosion and rod internal pressure evaluation in the frame of the cyclespecificnuclear core design.) The Tavg optimization method takes into account two effects, that are opposed to each other: the impact of steam pressure on the electrical power output versus the impact of Tavg on the cost of reactor fuel. The positive economical impact of a Tavg increase through the increase in MWe output is around 6 to 8 times higher than the corresponding negative impact on the fuel cost. From this perspective, it is desirable to have Tavg as high as possible. This statement is not affected by a change in the relationship between steam pressure and Tavg level. However, there are also other considerations intervening in the definition of the optimum. This paper discusses the procedure for selection of optimal Tavg for the forthcoming cycle in relation to the impacts of change in Tavg level and/or variations of the steam pressure versus Tavg relationship. (author)

Evaluation of surface air temperature and urban effects in Japan simulated by non-hydrostatic regional climate model

Science.gov (United States)

Murata, A.; Sasaki, H.; Hanafusa, M.; Kurihara, K.

2012-12-01

We evaluated the performance of a well-developed nonhydrostatic regional climate model (NHRCM) with a spatial resolution of 5 km with respect to temperature in the present-day climate of Japan, and estimated urban heat island (UHI) intensity by comparing the model results and observations. The magnitudes of root mean square error (RMSE) and systematic error (bias) for the annual average of daily mean (Ta), maximum (Tx), and minimum (Tn) temperatures are within 1.5 K, demonstrating that the temperatures of the present-day climate are reproduced well by NHRCM. These small errors indicate that temperature variability produced by local-scale phenomena is represented well by the model with a higher spatial resolution. It is also found that the magnitudes of RMSE and bias in the annually-average Tx are relatively large compared with those in Ta and Tn. The horizontal distributions of the error, defined as the difference between simulated and observed temperatures (simulated minus observed), illustrate negative errors in the annually-averaged Tn in three major metropolitan areas: Tokyo, Osaka, and Nagoya. These negative errors in urban areas affect the cold bias in the annually-averaged Tx. The relation between the underestimation of temperature and degree of urbanization is therefore examined quantitatively using National Land Numerical Information provided by the Ministry of Land, Infrastructure, Transport, and Tourism. The annually-averaged Ta, Tx, and Tn are all underestimated in the areas where the degree of urbanization is relatively high. The underestimations in these areas are attributed to the treatment of urban areas in NHRCM, where the effects of urbanization, such as waste heat and artificial structures, are not included. In contrast, in rural areas, the simulated Tx is underestimated and Tn is overestimated although the errors in Ta are small. This indicates that the simulated diurnal temperature range is underestimated. The reason for the relatively large

Temperature, productivity and sediment characteristics as drivers of seasonal and spatial variations of dissolved methane in the near-shore coastal areas (Belgian coastal zone, North Sea)

Science.gov (United States)

Borges, Alberto V.; Speeckaert, Gaëlle; Champenois, Willy; Scranton, Mary I.; Gypens, Nathalie

2017-04-01

The open ocean is a modest source of CH4 to the atmosphere compared to other natural and anthropogenic CH4 emissions. Coastal regions are more intense sources of CH4 to the atmosphere than open oceanic waters, in particular estuarine zones. The CH4 emission to the atmosphere from coastal areas is sustained by riverine inputs and methanogenesis in the sediments due to high organic matter (OM) deposition. Additionally, natural gas seeps are sources of CH4 to bottom waters leading to high dissolved CH4 concentrations in bottom waters (from tenths of nmol L-1 up to several µmol L-1). We report a data set of dissolved CH4 concentrations obtained at nine fixed stations in the Belgian coastal zone (Southern North Sea), during one yearly cycle, with a bi-monthly frequency in spring, and a monthly frequency during the rest of the year. This is a coastal area with multiple possible sources of CH4 such as from rivers and gassy sediments, and where intense phytoplankton blooms are dominated by the high dimethylsulfoniopropionate (DMSP) producing micro-algae Phaeocystis globosa, leading to DMSP and dimethylsulfide (DMS) concentrations. Furthermore, the BCZ is a site of important OM sedimentation and accumulation unlike the rest of the North Sea. Spatial variations of dissolved CH4 concentrations were very marked with a minimum yearly average of 9 nmol L-1 in one of the most off-shore stations and maximum yearly average of 139 nmol L-1 at one of the most near-shore stations. The spatial variations of dissolved CH4 concentrations were related to the organic matter (OM) content of sediments, although the highest concentrations seemed to also be related to inputs of CH4 from gassy sediments associated to submerged peat. In the near-shore stations with fine sand or muddy sediments with a high OM content, the seasonal cycle of dissolved CH4 concentration closely followed the seasonal cycle of water temperature, suggesting the control of methanogenesis by temperature in these OM

Autonomous distributed temperature sensing for long-term heated applications in remote areas

Directory of Open Access Journals (Sweden)

A.-M. Kurth

2013-02-01

Full Text Available Distributed temperature sensing (DTS is a fiber-optical method enabling simultaneous temperature measurements over long distances. Electrical resistance heating of the metallic components of the fiber-optic cable provides information on the thermal characteristics of the cable's environment, providing valuable insight into processes occurring in the surrounding medium, such as groundwater–surface water interactions, dam stability or soil moisture. Until now, heated applications required direct handling of the DTS instrument by a researcher, rendering long-term investigations in remote areas impractical due to the often difficult and time-consuming access to the field site. Remote control and automation of the DTS instrument and heating processes, however, resolve the issue with difficult access. The data can also be remotely accessed and stored on a central database. The power supply can be grid independent, although significant infrastructure investment is required here due to high power consumption during heated applications. Solar energy must be sufficient even in worst case scenarios, e.g. during long periods of intense cloud cover, to prevent system failure due to energy shortage. In combination with storage batteries and a low heating frequency, e.g. once per day or once per week (depending on the season and the solar radiation on site, issues of high power consumption may be resolved. Safety regulations dictate adequate shielding and ground-fault protection, to safeguard animals and humans from electricity and laser sources. In this paper the autonomous DTS system is presented to allow research with heated applications of DTS in remote areas for long-term investigations of temperature distributions in the environment.

Risk to a Changing Climate in the Mexico City Metropolitan Area

Science.gov (United States)

Vargas, N. D.

2016-12-01

The issue of climate change has dominated the atmospheric sciences agenda in recent decades. The concern about an increase in climate related disasters, mainly in large population centers, has led to ask whether they are mainly due to changes in climate or in vulnerability.The Mexico City Metropolitan Area (MCMA) is an example of megalopolis under high climate risk, where floods, landslides, health problems, high air pollution events, socioeconomic droughts are becoming important environmental and social problems. As urbanization spreads and population increases exposure to natural hazards increases, and so the magnitude of risk to a changing climate and the negative impacts. Since the late nineteenth century, in the MCMA an average maximum temperature could be around 22°C, whereas today it is about 24.5ºC. That is, the increase in the average temperature in Mexico City is around 3°C in a hundred years. But there are areas where an increase in the average temperature is similar in only thirty years. The heating rate of the city can vary depending on the change in land use. Areas that conserve forested regions in the process of urbanization tend to warm less than areas where the transformation into concrete and cement is almost complete. Thus, the climate of the MCMA shows important changes mainly in relation to land use changes. Global warming and natural climate variability were also analyzed as possible forcing factors of the observed warming by comparing low frequency variations in local temperature and indices for natural forcing. The hydrological cycle of the MCMA has also changed with urbanization. The "bubble of hot air" over the urban area has more capacity to hold moisture now than before the UHI. However, the increased risk to floods, heat or drought appears to be related not only to more frequent intense climatic hazards induced by the urbanization effect. This process also induces increased vulnerability to a changing climate. The establishment of

Subsurface thermal regime to delineate the paleo-groundwater flow system in an arid area, Al Kufra, Libya

Directory of Open Access Journals (Sweden)

Zenhom El-Said Salem

2016-12-01

Full Text Available The purpose of this study was to understand the groundwater flow system in Al Kufra basin, Libya, as a case study of arid areas using subsurface temperature. The temperature-depth profiles and water levels were measured in eight boreholes in the area. Well 6 is considered a recharge type profile with low geothermal gradient (0.0068 °C/m and an estimated paleo-temperature around 19.5 °C. The other profiles are of discharge type with higher geothermal gradient (0.0133 to 0.0166 °C/m. The constructed horizontal 2D distribution maps of the hydraulic heads and the subsurface temperature measurements reveal that the main recharge area is located to the south with low temperature while the main discharge area is located to the north with higher temperature. Vertical 2D distribution maps show that location of well 4 has low hydraulic heads and higher temperature indicating that the fault defined in the area may have affected the groundwater flow system. The estimated groundwater flux ranges from 0.001 to 0.1 mm/day for the recharge area and from −0.3 to −0.7 mm/day in average in the discharge area.

Variability of emissivity and surface temperature over a sparsely vegetated surface

International Nuclear Information System (INIS)

Humes, K.S.; Kustas, W.P.; Moran, M.S.; Nichols, W.D.; Weltz, M.A.

1994-01-01

Radiometric surface temperatures obtained from remote sensing measurements are a function of both the physical surface temperature and the effective emissivity of the surface within the band pass of the radiometric measurement. For sparsely vegetated areas, however, a sensor views significant fractions of both bare soil and various vegetation types. In this case the radiometric response of a sensor is a function of the emissivities and kinetic temperatures of various surface elements, the proportion of those surface elements within the field of view of the sensor, and the interaction of radiation emitted from the various surface components. In order to effectively utilize thermal remote sensing data to quantify energy balance components for a sparsely vegetated area, it is important to examine the typical magnitude and degree of variability of emissivity and surface temperature for such surfaces. Surface emissivity measurements and ground and low-altitude-aircraft-based surface temperature measurements (8-13 micrometer band pass) made in conjunction with the Monsoon '90 field experiment were used to evaluate the typical variability of those quantities during the summer rainy season in a semiarid watershed. The average value for thermal band emissivity of the exposed bare soil portions of the surface was found to be approximately 0.96; the average value measured for most of the varieties of desert shrubs present was approximately 0.99. Surface composite emissivity was estimated to be approximately 0.98 for both the grass-dominated and shrub-dominated portions of the watershed. The spatial variability of surface temperature was found to be highly dependent on the spatial scale of integration for the instantaneous field of view (IFOV) of the instrument, the spatial scale of the total area under evaluation, and the time of day

Range of monthly mean hourly land surface air temperature diurnal cycle over high northern latitudes

Science.gov (United States)

Wang, Aihui; Zeng, Xubin

2014-05-01

Daily maximum and minimum temperatures over global land are fundamental climate variables, and their difference represents the diurnal temperature range (DTR). While the differences between the monthly averaged DTR (MDTR) and the range of monthly averaged hourly temperature diurnal cycle (RMDT) are easy to understand qualitatively, their differences have not been quantified over global land areas. Based on our newly developed in situ data (Climatic Research Unit) reanalysis (Modern-Era Retrospective analysis for Research and Applications) merged hourly temperature data from 1979 to 2009, RMDT in January is found to be much smaller than that in July over high northern latitudes, as it is much more affected by the diurnal radiative forcing than by the horizontal advection of temperature. In contrast, MDTR in January is comparable to that in July over high northern latitudes, but it is much larger than January RMDT, as it primarily reflects the movement of lower frequency synoptic weather systems. The area-averaged RMDT trends north of 40°N are near zero in November, December, and January, while the trends of MDTR are negative. These results suggest the need to use both the traditional MDTR and RMDT suggested here in future observational and modeling studies. Furthermore, MDTR and its trend are more sensitive to the starting hour of a 24 h day used in the calculations than those for RMDT, and this factor also needs to be considered in model evaluations using observational data.

Land surface temperature representativeness in a heterogeneous area through a distributed energy-water balance model and remote sensing data

Directory of Open Access Journals (Sweden)

C. Corbari

2010-10-01

Full Text Available Land surface temperature is the link between soil-vegetation-atmosphere fluxes and soil water content through the energy water balance. This paper analyses the representativeness of land surface temperature (LST for a distributed hydrological water balance model (FEST-EWB using LST from AHS (airborne hyperspectral scanner, with a spatial resolution between 2–4 m, LST from MODIS, with a spatial resolution of 1000 m, and thermal infrared radiometric ground measurements that are compared with the representative equilibrium temperature that closes the energy balance equation in the distributed hydrological model.

Diurnal and nocturnal images are analyzed due to the non stable behaviour of the thermodynamic temperature and to the non linear effects induced by spatial heterogeneity.

Spatial autocorrelation and scale of fluctuation of land surface temperature from FEST-EWB and AHS are analysed at different aggregation areas to better understand the scale of representativeness of land surface temperature in a hydrological process.

The study site is the agricultural area of Barrax (Spain that is a heterogeneous area with a patchwork of irrigated and non irrigated vegetated fields and bare soil. The used data set was collected during a field campaign from 10 to 15 July 2005 in the framework of the SEN2FLEX project.

Dependence of the coefficient of environmental thermal losses of radiation-absorbing thermal exchange panels of flat solar collectors for heating heat-transfer fluid from their average operating and ambient temperatures

International Nuclear Information System (INIS)

Avezova, N.R.; Avezov, R.R.

2015-01-01

The approximation formula is derived for calculating the normalized coefficient of thermal losses of flat solar collectors (FSCs) for heating heat-transfer fluid (HTF). These are used in hot water supply systems in the warmer part of the year, depending on the average working surface temperature of their radiation-absorbing thermal exchange panels (RATEPs) (t"-_w_s_r) and the ambient temperature (t_a_m_b) in their realistic variation range. (author)

Cross-sectional area of the murine aorta linearly increases with increasing core body temperature.

Science.gov (United States)

Crouch, A Colleen; Manders, Adam B; Cao, Amos A; Scheven, Ulrich M; Greve, Joan M

2017-11-06

The cardiovascular (CV) system plays a vital role in thermoregulation. To date, the response of core vasculature to increasing core temperature has not been adequately studied in vivo. Our objective was to non-invasively quantify the arterial response in murine models due to increases in body temperature, with a focus on core vessels of the torso and investigate whether responses were dependent on sex or age. Male and female, adult and aged mice were anaesthetised and underwent magnetic resonance imaging (MRI). Data were acquired from the circle of Willis (CoW), heart, infrarenal aorta and peripheral arteries at core temperatures of 35, 36, 37 and 38 °C (±0.2 °C). Vessels in the CoW did not change. Ejection fraction decreased and cardiac output (CO) increased with increasing temperature in adult female mice. Cross-sectional area of the aorta increased significantly and linearly with temperature for all groups, but at a diminished rate for aged animals (p temperature are biologically important because they may affect conductive and convective heat transfer. Leveraging non-invasive methodology to quantify sex and age dependent vascular responses due to increasing core temperature could be combined with bioheat modelling in order to improve understanding of thermoregulation.

Pattern Analysis of El Nino and La Nina Phenomenon Based on Sea Surface Temperature (SST) and Rainfall Intensity using Oceanic Nino Index (ONI) in West Java Area

Science.gov (United States)

Prasetyo, Yudo; Nabilah, Farras

2017-12-01

Climate change occurs in 1998-2016 brings significant alteration in the earth surface. It is affects an extremely anomaly temperature such as El Nino and La Nina or mostly known as ENSO (El Nino Southern Oscillation). West Java is one of the regions in Indonesia that encounters the impact of this phenomenon. Climate change due to ENSO also affects food production and other commodities. In this research, processing data method is conducted using programming language to process SST data and rainfall data from 1998 to 2016. The data are sea surface temperature from NOAA satellite, SST Reynolds (Sea Surface Temperature) and daily rainfall temperature from TRMM satellite. Data examination is done using analysis of rainfall spatial pattern and sea surface temperature (SST) where is affected by El Nino and La Nina phenomenon. This research results distribution map of SST and rainfall for each season to find out the impacts of El Nino and La Nina around West Java. El Nino and La Nina in Java Sea are occurring every August to February. During El Nino, sea surface temperature is between 27°C - 28°C with average temperature on 27.71°C. Rainfall intensity is 1.0 mm/day - 2.0 mm/day and the average are 1.63 mm/day. During La Nina, sea surface temperature is between 29°C - 30°C with average temperature on 29.06°C. Rainfall intensity is 9.0 mm/day - 10 mm/day, and the average is 9.74 mm/day. The correlation between rainfall and SST is 0,413 which is expresses a fairly strong correlation between parameters. The conclusion is, during La Nina SST and rainfall increase. While during El Nino SST and rainfall decrease. Hopefully this research could be a guideline to plan disaster mitigation in West Java region that is related extreme climate change.

The Morphology, Dynamics and Potential Hotspots of Land Surface Temperature at a Local Scale in Urban Areas

Directory of Open Access Journals (Sweden)

Jiong Wang

2015-12-01

Full Text Available Current characterization of the Urban Heat Island (UHI remains insufficient to support the effective mitigation and adaptation of increasing temperatures in urban areas. Planning and design strategies are restricted to the investigation of temperature anomalies at a city scale. By focusing on Land Surface Temperature of Wuhan, China, this research examines the temperature variations locally where mitigation and adaptation would be more feasible. It shows how local temperature anomalies can be identified morphologically. Technically, the MODerate-resolution Imaging Spectroradiometer satellite image products are used. They are first considered as noisy observations of the latent temperature patterns. The continuous latent patterns of the temperature are then recovered from these discrete observations by using the non-parametric Multi-Task Gaussian Process Modeling. The Multi-Scale Shape Index is then applied in the area of focus to extract the local morphological features. A triplet of shape, curvedness and temperature is formed as the criteria to extract local heat islands. The behavior of the local heat islands can thus be quantified morphologically. The places with critical deformations are identified as hotpots. The hotspots with certain yearly behavior are further associated with land surface composition to determine effective mitigation and adaptation strategies. This research can assist in the temperature and planning field on two levels: (1 the local land surface temperature patterns are characterized by decomposing the variations into fundamental deformation modes to allow a process-based understanding of the dynamics; and (2 the characterization at local scale conforms to planning and design conventions where mitigation and adaptation strategies are supposed to be more practical. The weaknesses and limitations of the study are addressed in the closing section.

Locatable-body temperature monitoring based on semi-active UHF RFID tags.

Science.gov (United States)

Liu, Guangwei; Mao, Luhong; Chen, Liying; Xie, Sheng

2014-03-26

This paper presents the use of radio-frequency identification (RFID) technology for the real-time remote monitoring of body temperature, while an associated program can determine the location of the body carrying the respective sensor. The RFID chip's internal integrated temperature sensor is used for both the human-body temperature detection and as a measurement device, while using radio-frequency communication to broadcast the temperature information. The adopted RFID location technology makes use of reference tags together with a nearest neighbor localization algorithm and a multiple-antenna time-division multiplexing location system. A graphical user interface (GUI) was developed for collecting temperature and location data for the data fusion by using RFID protocols. With a puppy as test object, temperature detection and localization experiments were carried out. The measured results show that the applied method, when using a mercury thermometer for comparison in terms of measuring the temperature of the dog, has a good consistency, with an average temperature error of 0.283 °C. When using the associated program over the area of 12.25 m2, the average location error is of 0.461 m, which verifies the feasibility of the sensor-carrier location by using the proposed program.

Locatable-Body Temperature Monitoring Based on Semi-Active UHF RFID Tags

Directory of Open Access Journals (Sweden)

Guangwei Liu

2014-03-01

Full Text Available This paper presents the use of radio-frequency identification (RFID technology for the real-time remote monitoring of body temperature, while an associated program can determine the location of the body carrying the respective sensor. The RFID chip’s internal integrated temperature sensor is used for both the human-body temperature detection and as a measurement device, while using radio-frequency communication to broadcast the temperature information. The adopted RFID location technology makes use of reference tags together with a nearest neighbor localization algorithm and a multiple-antenna time-division multiplexing location system. A graphical user interface (GUI was developed for collecting temperature and location data for the data fusion by using RFID protocols. With a puppy as test object, temperature detection and localization experiments were carried out. The measured results show that the applied method, when using a mercury thermometer for comparison in terms of measuring the temperature of the dog, has a good consistency, with an average temperature error of 0.283 °C. When using the associated program over the area of 12.25 m2, the average location error is of 0.461 m, which verifies the feasibility of the sensor-carrier location by using the proposed program.

The Effects of Forest Area Changes on Extreme Temperature Indexes between the 1900s and 2010s in Heilongjiang Province, China

Directory of Open Access Journals (Sweden)

Lijuan Zhang

2017-12-01

Full Text Available Land use and land cover changes (LUCC are thought to be amongst the most important impacts exerted by humans on climate. However, relatively little research has been carried out so far on the effects of LUCC on extreme climate change other than on regional temperatures and precipitation. In this paper, we apply a regional weather research and forecasting (WRF climate model using LUCC data from Heilongjiang Province, that was collected between the 1900s and 2010s, to explore how changes in forest cover influence extreme temperature indexes. Our selection of extreme high, low, and daily temperature indexes for analysis in this study enables the calculation of a five-year numerical integration trail with changing forest space. Results indicate that the total forested area of Heilongjiang Province decreased by 28% between the 1900s and 2010s. This decrease is most marked in the western, southwestern, and northeastern parts of the province. Our results also reveal a remarkable correlation between change in forested area and extreme high and low temperature indexes. Further analysis enabled us to determine that the key factor explaining increases in extreme high temperature indexes (i.e., calculated using the number of warm days, warm nights, as well as tropical nights, and summer days is decreasing forest area; data also showed that this factor caused a decrease in extreme low temperature indexes (i.e., calculated using the number of cold days and cold nights, as well as frost days, and ice days and an increase in the maximum value of daily minimum temperature. Spatial data demonstrated that there is a significant correlation between forest-to-farmland conversion and extreme temperature indexes throughout most of our study period. Spatial data demonstrated that there is a significant correlation between forest-to-farmland conversion and extreme temperature indexes throughout most of our study period. Positive correlations are also present between

Self-consistent transport coefficients for average collective motion at moderately high temperatures

International Nuclear Information System (INIS)

Yamaji, Shuhei; Hofmann, H.; Samhammer, R.

1987-01-01

Linear response theory is applied to compute the coefficients for inertia, friction and local stiffness for slow, large scale nuclear collective motion. It is shown how these coefficients can be defined within a locally harmonic approximation. The latter allows to study the implications arising from a finite local collective frequency. It is only for temperatures around 2 MeV that the zero frequency limit becomes a fair approximation. Friction is found to have a marked temperature dependence. The numerical computations are performed on the basis of a two-center shell model, but allowing the particles and holes to become dressed through effects of the medium. The dependence of the transport coefficients on the parameters of these self-energies is studied. It is argued that the uncertainties are smaller than a factor of 2. (orig.)

X-ray spectroscopic study of nonequilibrium laser produced plasma in porous targets of low average density

Energy Technology Data Exchange (ETDEWEB)

Burdonskiy, I.N.; Dimitrenko, V.V.; Fasakhov, I.K.; Gavrilov, V.V.; Goltsov, A.Y.; Kovalskii, N.G.; Mironov, B.N. [Science Research Center of Russian Federation Troitsk Institute for Innovation and Fusion Research, Troitsk, Moscow Reg. (Russian Federation); Faenov, A.Y.; Magunov, A.I.; Pikuz, T.A.; Skobelev, I.Y. [Multicharged Ions Spectra Data Center, VNIIFTRI, Mendeleevo (Russian Federation)

2006-06-15

New experimental results on laser irradiation (I {<=} 10{sup 14} W/cm{sup 2}, {lambda} = 1.053 {mu}m) of low-density fibrous agar are presented. X-ray spectrometers with spherically bent mica crystals were used for measuring with high spectral resolution the line spectra of multicharged ions. Detailed analysis of the measured spectra made it possible to determine the temperature of electrons and ions in hot plasma created in laser irradiated low-density samples in dependence on average material density and average intensity within a focal spot. Both the ion and electron temperatures are found to decrease by a factor 1.5 - 2 following a factor of about 3 as increase of the target average density (5 mg/cm{sup 3} and 15 mg/cm{sup 3}) for I 5*10{sup 13} W/cm{sup 2}. In all cases the ion temperature exceeds the electron temperature by a factor of 2 - 3.

RESEARCH ON THE HOMOGENEITY OF TEMPERATURES IN JOINT'S AREA BY VULCANIZING THE CONVEYOR BELTS

Directory of Open Access Journals (Sweden)

Dan DOBROTA

2016-05-01

Full Text Available The researches presented in this paper have followed the analysis of the heat transfer mode during joining through vulcanization of the conveyor belts and also the homogeneity of the temperatures in the joint area. The researches were made under laboratory conditions taking into account the process of joining of two conveyor belts of the type ST 2000 with an installation of the type DSLQ. Temperature measurement was conducted using an EX42570 pyrometer in four distinct points corresponding to each end of the two conveyor belts on the both sides of the band, namely the active and inactive side.

Changes in Skin Surface Temperature during Muscular Endurance indicated Strain – An Explorative Study

Directory of Open Access Journals (Sweden)

Michael Fröhlich

2014-07-01

Full Text Available Introduction: Non-contact thermography enables the diagnosis of the distribution of skin surface temperature during athletic movement. Resistance exercise results in stress of required musculature, which is supposed to be measurable thermographically in terms of skin surface temperature change. Objective: This study aims to evaluate the application of thermography to analyze changes in skin temperature, representing specific muscle groups, during and after resistance exercise. Method: Thirteen male participants (age: 27.1 ± 4.9 years, height: 181.5 ± 5.7 cm, mass: 74.8 ± 7.4 kg completed the study. On 5 separate visits to the laboratory, participants performed one of 5 resistance exercise to target specific muscles (M. pectoralis major, M. rectus abdominis, M. trapezius, M. erector spinae, M. quadriceps femoris. The exercise protocol consisted of 3 sets of 20 repetitions, with 1 minute rest between exercise sets. The average skin surface temperature above the muscle groups used was thermographically determined using standard methods at 7 time points; pre-exercise, immediately following each exercise set, and post exercise (2, 3, and 6 minutes after the finale exercise set. The measurement areas were standardized using anatomic reference points. Results: From an inferential statistical point of view, no significant change in the average temperature caused by the applied resistance training was found for the individual muscle groups over time at the individual measurement times (all P>0.08. However, thermography showed a characteristic chronological temperature curve for the five body areas between measurement times, as well as a distinctive spatial temperature distribution over the measurement areas. Discussion: Based on the thermographic image data and the characteristic temperature curve, it is possible to identify the primarily used functional musculature after device-controlled resistance training. Therefore, thermography seems to be

THE EFFECTS OF CLIMATIC VARIABLES AND CROP AREA ON MAIZE YIELD AND VARIABILITY IN GHANA

Directory of Open Access Journals (Sweden)

Henry De-Graft Acquah

2012-10-01

Full Text Available Climate change tends to have negative effects on crop yield through its influence on crop production. Understanding the relationship between climatic variables and crop area on the mean and variance of crop yield will facilitate development of appropriate policies to cope with climate change. This paper examines the effects of climatic variables and crop area on the mean and variance of maize yield in Ghana. The Just and Pope stochastic production function using the Cobb-Douglas functional form was employed. The results show that average maize yield is positively related to crop area and negatively related to rainfall and temperature. Furthermore, increase in crop area and temperature will enlarge maize yield variability while rainfall increase will decrease the variability in maize yield.

Data Point Averaging for Computational Fluid Dynamics Data

Science.gov (United States)

Norman, Jr., David (Inventor)

2016-01-01

A system and method for generating fluid flow parameter data for use in aerodynamic heating analysis. Computational fluid dynamics data is generated for a number of points in an area on a surface to be analyzed. Sub-areas corresponding to areas of the surface for which an aerodynamic heating analysis is to be performed are identified. A computer system automatically determines a sub-set of the number of points corresponding to each of the number of sub-areas and determines a value for each of the number of sub-areas using the data for the sub-set of points corresponding to each of the number of sub-areas. The value is determined as an average of the data for the sub-set of points corresponding to each of the number of sub-areas. The resulting parameter values then may be used to perform an aerodynamic heating analysis.

[Study on plasma temperature of a large area surface discharge by optical emission spectrum].

Science.gov (United States)

Dong, Li-Fang; Tong, Guo-Liang; Zhang, Yu; Zhou, Bin

2014-04-01

A large area surface discharge was realized in air/argon gas mixture by designing a discharge device with water electrodes. By using optical emission spectrum, the variations of the molecular vibrational temperature, the mean energy of electron, and the electronic excitation temperature as a function of the gas pressure were studied. The nitrogen molecular vibrational temperature was calculated according to the emission line of the second positive band system of the nitrogen molecule (C3 pi(u) --> B 3 pi(g)). The electronic excitation temperature was obtained by using the intensity ratio of Ar I 763.51 nm (2P(6) --> 1S(5)) to Ar I 772.42 nm (2P(2) --> 1S(3)). The changes in the mean energy of electron were studied by the relative intensity ratio of the nitrogen molecular ion 391.4 nm to nitrogen 337.1 nm. It was found that the intensity of emission spectral line increases with the increase in the gas pressure, meanwhile, the outline and the ratios of different spectral lines intensity also change. The molecular vibrational temperature, the mean energy of electron, and the electronic excitation temperature decrease as the gas pressure increases from 0.75 x 10(5) Pa to 1 x 10(5) Pa.

Spatial distribution of unidirectional trends in temperature and temperature extremes in Pakistan

Science.gov (United States)

Khan, Najeebullah; Shahid, Shamsuddin; Ismail, Tarmizi bin; Wang, Xiao-Jun

2018-06-01

Pakistan is one of the most vulnerable countries of the world to temperature extremes due to its predominant arid climate and geographic location in the fast temperature rising zone. Spatial distribution of the trends in annual and seasonal temperatures and temperature extremes over Pakistan has been assessed in this study. The gauge-based gridded daily temperature data of Berkeley Earth Surface Temperature (BEST) having a spatial resolution of 1° × 1° was used for the assessment of trends over the period 1960-2013 using modified Mann-Kendall test (MMK), which can discriminate the multi-decadal oscillatory variations from secular trends. The results show an increase in the annual average of daily maximum and minimum temperatures in 92 and 99% area of Pakistan respectively at 95% level of confidence. The annual temperature is increasing faster in southern high-temperature region compared to other parts of the country. The minimum temperature is rising faster (0.17-0.37 °C/decade) compared to maximum temperature (0.17-0.29 °C/decade) and therefore declination of diurnal temperature range (DTR) (- 0.15 to - 0.08 °C/decade) in some regions. The annual numbers of both hot and cold days are increasing in whole Pakistan except in the northern sub-Himalayan region. Heat waves are on the rise, especially in the hot Sindh plains and the Southern coastal region, while the cold waves are becoming lesser in the northern cold region. Obtained results contradict with the findings of previous studies on temperature trends, which indicate the need for reassessment of climatic trends in Pakistan using the MMK test to understand the anthropogenic impacts of climate change.

Maxwellian-averaged cross sections calculated from JENDL-3.2

Energy Technology Data Exchange (ETDEWEB)

Nakagawa, Tsuneo; Chiba, Satoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Ohsaka, Toshiro; Igashira, Masayuki [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Tokyo (Japan)

2000-02-01

Maxwellian-averaged cross sections of neutron capture, fission, (n,p) and (n,{alpha}) reactions are calculated from the Japanese Evaluated Nuclear Data Library, JENDL-3.2, for applications in the astrophysics. The calculation was made in the temperature (kT) range from 1 keV to 1 MeV. Results are listed in tables. The Maxwellian-averaged capture cross sections were compared with recommendations of other authors and recent experimental data. Large discrepancies were found among them especially in the light mass nuclides. Since JENDL-3.2 reproduces relatively well the recent experimental data, we conclude that JENDL-3.2 is superior to the others in such a mass region. (author)

Averaged 30 year climate change projections mask opportunities for species establishment

Science.gov (United States)

Serra-Diaz, Josep M.; Franklin, Janet; Sweet, Lynn C.; McCullough, Ian M.; Syphard, Alexandra D.; Regan, Helen M.; Flint, Lorraine E.; Flint, Alan L.; Dingman, John; Moritz, Max A.; Redmond, Kelly T.; Hannah, Lee; Davis, Frank W.

2016-01-01

Survival of early life stages is key for population expansion into new locations and for persistence of current populations (Grubb 1977, Harper 1977). Relative to adults, these early life stages are very sensitive to climate fl uctuations (Ropert-Coudert et al. 2015), which often drive episodic or ‘event-limited’ regeneration (e.g. pulses) in long-lived plant species (Jackson et al. 2009). Th us, it is diffi cult to mechanistically associate 30-yr climate norms to dynamic processes involved in species range shifts (e.g. seedling survival). What are the consequences of temporal aggregation for estimating areas of potential establishment? We modeled seedling survival for three widespread tree species in California, USA ( Quercus douglasii, Q. kelloggii , Pinus sabiniana ) by coupling a large-scale, multi-year common garden experiment to high-resolution downscaled grids of climatic water defi cit and air temperature (Flint and Flint 2012, Supplementary material Appendix 1). We projected seedling survival for nine climate change projections in two mountain landscapes spanning wide elevation and moisture gradients. We compared areas with windows of opportunity for seedling survival – defi ned as three consecutive years of seedling survival in our species, a period selected based on studies of tree niche ontogeny (Supplementary material Appendix 1) – to areas of 30-yr averaged estimates of seedling survival. We found that temporal aggregation greatly underestimated the potential for species establishment (e.g. seedling survival) under climate change scenarios.

State Averages

Data.gov (United States)

U.S. Department of Health & Human Services — A list of a variety of averages for each state or territory as well as the national average, including each quality measure, staffing, fine amount and number of...

Temperature changes in Three Gorges Reservoir Area and linkage with Three Gorges Project

Science.gov (United States)

Song, Zhen; Liang, Shunlin; Feng, Lian; He, Tao; Song, Xiao-Peng; Zhang, Lei

2017-05-01

The Three Gorges Project (TGP) is one of the largest hydroelectric projects throughout the world. It has brought many benefits to the society but also led to endless debates about its environmental and climatic impacts. Monitoring the spatiotemporal variations of temperature in the Three Gorges Reservoir Area (TGRA) is important for understanding the climatic impacts of the TGP. In this study, we used remote sensing-based land surface temperature (LST) and ground-measured air temperature data to investigate temperature changes in the TGRA. Results showed that during the daytime in summer, LST exhibited significant cooling (1-5°C) in the downstream region of the reservoir, whereas LST during the nighttime in winter exhibited significant warming (1-5°C) across the entire reservoir. However, these cooling and warming effects were both locally constrained within 5 km buffer along the reservoir. The changes in air temperature were consistent with those in LST, with 0.67°C cooling in summer and 0.33°C warming in winter. The temperature changes along the reservoir not only resulted from the land-water conversion induced by the dam impounding but were also related to the increase of vegetation cover caused by the ecological restoration projects. Significant warming trends were also found in the upstream of TGRA, especially during the daytime in summer, with up to 5°C for LST and 0.52°C for air temperature. The warming was caused mainly by urban expansion, which was driven in part by the population resettlement of TGP. Based on satellite observations, we investigated the comprehensive climatic impacts of TGP caused by multiple factors.

A STUDY OF SOLAR PHOTOSPHERIC TEMPERATURE GRADIENT VARIATION USING LIMB DARKENING MEASUREMENTS

Energy Technology Data Exchange (ETDEWEB)

Criscuoli, Serena [National Solar Observatory, Boulder, CO 80303 (United States); Foukal, Peter [192 Willow Road, Nahant, MA 01908 (United States)

2017-01-20

The variation in area of quiet magnetic network measured over the sunspot cycle should modulate the spatially averaged photospheric temperature gradient, since temperature declines with optical depth more gradually in magnetic flux tube atmospheres. Yet, limb darkening measurements show no dependence upon activity level, even at an rms precision of 0.04%. We study the sensitivity of limb darkening to changes in area filling factor using a 3D MHD model of the magnetized photosphere. The limb darkening change expected from the measured 11-year area variation lies below the level of measured limb darkening variations, for a reasonable range of magnetic flux in quiet network and internetwork regions. So the remarkably constant limb darkening observed over the solar activity cycle is not inconsistent with the measured 11-year change in area of quiet magnetic network. Our findings offer an independent constraint on photospheric temperature gradient changes reported from measurements of the solar spectral irradiance from the Spectral Irradiance Monitor, and recently, from wavelength-differential spectrophotometry using the Solar Optical Telescope aboard the HINODE spacecraft.

Aperture averaging and BER for Gaussian beam in underwater oceanic turbulence

Science.gov (United States)

Gökçe, Muhsin Caner; Baykal, Yahya

2018-03-01

In an underwater wireless optical communication (UWOC) link, power fluctuations over finite-sized collecting lens are investigated for a horizontally propagating Gaussian beam wave. The power scintillation index, also known as the irradiance flux variance, for the received irradiance is evaluated in weak oceanic turbulence by using the Rytov method. This lets us further quantify the associated performance indicators, namely, the aperture averaging factor and the average bit-error rate (). The effects on the UWOC link performance of the oceanic turbulence parameters, i.e., the rate of dissipation of kinetic energy per unit mass of fluid, the rate of dissipation of mean-squared temperature, Kolmogorov microscale, the ratio of temperature to salinity contributions to the refractive index spectrum as well as system parameters, i.e., the receiver aperture diameter, Gaussian source size, laser wavelength and the link distance are investigated.

Estimating 1970-99 average annual groundwater recharge in Wisconsin using streamflow data

Science.gov (United States)

Gebert, Warren A.; Walker, John F.; Kennedy, James L.

2011-01-01

Average annual recharge in Wisconsin for the period 1970-99 was estimated using streamflow data from U.S. Geological Survey continuous-record streamflow-gaging stations and partial-record sites. Partial-record sites have discharge measurements collected during low-flow conditions. The average annual base flow of a stream divided by the drainage area is a good approximation of the recharge rate; therefore, once average annual base flow is determined recharge can be calculated. Estimates of recharge for nearly 72 percent of the surface area of the State are provided. The results illustrate substantial spatial variability of recharge across the State, ranging from less than 1 inch to more than 12 inches per year. The average basin size for partial-record sites (50 square miles) was less than the average basin size for the gaging stations (305 square miles). Including results for smaller basins reveals a spatial variability that otherwise would be smoothed out using only estimates for larger basins. An error analysis indicates that the techniques used provide base flow estimates with standard errors ranging from 5.4 to 14 percent.

Evaluation of temperature distribution in a containment vessel during operation

International Nuclear Information System (INIS)

Utanohara, Yoichi; Murase, Michio; Yanagi, Chihiro; Masui, Akihiro; Inomata, Ryo; Kamiya, Yuji

2012-01-01

For safety analysis of the containment vessel (CV) in a nuclear power plant, the average temperature of the gas phase in the CV during operation is used as an initial condition. An actual CV, however, has a temperature distribution, which makes the estimation of the average temperature difficult. Numerical simulation seems to be useful for the average temperature estimation, but it has several difficulties such as predictions of temperature distribution in a large and closed space that has several compartments, and modeling the heat generating components and the convection-diffusion of heat by ventilation air-conditioning systems. The main purpose of this study was to simulate the temperature distribution and evaluate the average temperature in the CV of a three-loop pressurized water reactor (PWR) during the reactor operation. The simulation considered the heat generation of equipment, flow due to the ventilation and air conditioning systems, heat loss to the CV exterior, and the solar heat. The predicted temperature distribution was significantly affected by the flow. Particularly, openings, which became flow paths, affected the temperature distribution. The temperature increased with a rise in height within the CV and the flow field seemed to transform from forced convection to natural convection. The volume-averaged temperature was different between gas and solid (concrete, CV wall) phases as well as between heights. The total volume-averaged temperature of the CV was nearly equal to the average gas phase temperature. It was found to be easy to evaluate the effect of openings on the temperature distribution and estimate the average temperature in CV by numerical simulation. (author)

Method for biological tissue temperature measuring in the area of laser radiation exposure with a small size beam profile during laser welding

Science.gov (United States)

Ryabkin, Dmitrii I.

2018-04-01

Connection is not strong enough In case of insufficient or excessive temperature of the laser welding. As a result, the temperature measurement in laser welding is an important problem. Measurement area surface is small (3.12 mm2) and measurements shall be carried out by a Non-contact method, which makes them challenging. Method of temperature measurement by an infrared sensor in two positions has been offered. This method allows you to measure the temperature at a distance of up to 5 cm from the measured area with an accuracy of 8%.

Onset temperature for Si nanostructure growth on Si substrate during high vacuum electron beam annealing.

Science.gov (United States)

Fang, F; Markwitz, A

2009-05-01

Silicon nanostructures, called Si nanowhiskers, are successfully synthesized on Si(100) substrate by high vacuum electron beam annealing. The onset temperature and duration needed for the Si nanowhiskers to grow was investigated. It was found that the onset and growth morphology of Si nanowhiskers strongly depend on the annealing temperature and duration applied in the annealing cycle. The onset temperature for nanowhisker growth was determined as 680 degrees C using an annealing duration of 90 min and temperature ramps of +5 degrees C s(-1) for heating and -100 degrees C s(-1) for cooling. Decreasing the annealing time at peak temperature to 5 min required an increase in peak temperature to 800 degrees C to initiate the nanowhisker growth. At 900 degrees C the duration for annealing at peak temperature can be set to 0 s to grow silicon nanowhiskers. A correlation was found between the variation in annealing temperature and duration and the nanowhisker height and density. Annealing at 900 degrees C for 0 s, only 2-3 nanowhiskers (average height 2.4 nm) grow on a surface area of 5 x 5 microm, whereas more than 500 nanowhiskers with an important average height of 4.6 nm for field emission applications grow on the same surface area for a sample annealed at 970 degrees C for 0 s. Selected results are presented showing the possibility of controlling the density and height of Si nanowhisker growth for field emission applications by applying different annealing temperature and duration.

Microscopic description of average level spacing in even-even nuclei

International Nuclear Information System (INIS)

Huong, Le Thi Quynh; Hung, Nguyen Quang; Phuc, Le Tan

2017-01-01

A microscopic theoretical approach to the average level spacing at the neutron binding energy in even-even nuclei is proposed. The approach is derived based on the Bardeen-Cooper-Schrieffer (BCS) theory at finite temperature and projection M of the total angular momentum J , which is often used to describe the superfluid properties of hot rotating nuclei. The exact relation of the J -dependent total level density to the M -dependent state densities, based on which the average level spacing is calculated, was employed. The numerical calculations carried out for several even-even nuclei have shown that in order to reproduce the experimental average level spacing, the M -dependent pairing gaps as well as the exact relation of the J -dependent total level density formula should be simultaneously used. (paper)

The Statistical Differences Between the Gridded Temperature Datasets, and its Implications for Stochastic Modelling

Science.gov (United States)

Fredriksen, H. B.; Løvsletten, O.; Rypdal, M.; Rypdal, K.

2014-12-01

Several research groups around the world collect instrumental temperature data and combine them in different ways to obtain global gridded temperature fields. The three most well known datasets are HadCRUT4 produced by the Climatic Research Unit and the Met Office Hadley Centre in UK, one produced by NASA GISS, and one produced by NOAA. Recently Berkeley Earth has also developed a gridded dataset. All these four will be compared in our analysis. The statistical properties we will focus on are the standard deviation and the Hurst exponent. These two parameters are sufficient to describe the temperatures as long-range memory stochastic processes; the standard deviation describes the general fluctuation level, while the Hurst exponent relates the strength of the long-term variability to the strength of the short-term variability. A higher Hurst exponent means that the slow variations are stronger compared to the fast, and that the autocovariance function will have a stronger tail. Hence the Hurst exponent gives us information about the persistence or memory of the process. We make use of these data to show that data averaged over a larger area exhibit higher Hurst exponents and lower variance than data averaged over a smaller area, which provides information about the relationship between temporal and spatial correlations of the temperature fluctuations. Interpolation in space has some similarities with averaging over space, although interpolation is more weighted towards the measurement locations. We demonstrate that the degree of spatial interpolation used can explain some differences observed between the variances and memory exponents computed from the various datasets.

Trajectories in a marked temperature inversion in mountainous country

International Nuclear Information System (INIS)

Koppert, H.J.; Wippermann, F.

1980-01-01

This study investigates the flow conditions occurring in marked temperature inversions in mountainous country, which frequently arise in winter in high-pressure areas with low wind speeds. The problem is reduced to a two-dimensional one by vertical integration; since the highest mountains may extend into the inversion, the calculations must of course be carried out on a multi-compartment interdependent basis. The properties of the boundary layer are not taken into account in the vertical integration; only surface friction with the ground is introduced. Three comparisons are made for the three variables in the model (vertically averaged stream function, vertically averaged velocity potential and vertically averaged vorticity) and the conditions at the external and internal boundaries are defined. For the external boundaries, a distinction is drawn between the inflow and outflow boundaries of the area considered; the conditions for the former being determined by the overall (i.e. synoptic) wind conditions. As an example of application of the method, the flow pattern is calculated for the RHINE-MAIN area for an inversion height of 300 m above mean sea level. Trajectories from any chosen point can be obtained as subsidiary results and are given for 16 different overall wind directions, starting from the site of the BIBLIS nuclear power station

Effect of temporal averaging of meteorological data on predictions of groundwater recharge

Directory of Open Access Journals (Sweden)

Batalha Marcia S.

2018-06-01

Full Text Available Accurate estimates of infiltration and groundwater recharge are critical for many hydrologic, agricultural and environmental applications. Anticipated climate change in many regions of the world, especially in tropical areas, is expected to increase the frequency of high-intensity, short-duration precipitation events, which in turn will affect the groundwater recharge rate. Estimates of recharge are often obtained using monthly or even annually averaged meteorological time series data. In this study we employed the HYDRUS-1D software package to assess the sensitivity of groundwater recharge calculations to using meteorological time series of different temporal resolutions (i.e., hourly, daily, weekly, monthly and yearly averaged precipitation and potential evaporation rates. Calculations were applied to three sites in Brazil having different climatological conditions: a tropical savanna (the Cerrado, a humid subtropical area (the temperate southern part of Brazil, and a very wet tropical area (Amazonia. To simplify our current analysis, we did not consider any land use effects by ignoring root water uptake. Temporal averaging of meteorological data was found to lead to significant bias in predictions of groundwater recharge, with much greater estimated recharge rates in case of very uneven temporal rainfall distributions during the year involving distinct wet and dry seasons. For example, at the Cerrado site, using daily averaged data produced recharge rates of up to 9 times greater than using yearly averaged data. In all cases, an increase in the time of averaging of meteorological data led to lower estimates of groundwater recharge, especially at sites having coarse-textured soils. Our results show that temporal averaging limits the ability of simulations to predict deep penetration of moisture in response to precipitation, so that water remains in the upper part of the vadose zone subject to upward flow and evaporation.

Regional differences in the surface temperature of Naked Neck laying hens in a semi-arid environment.

Science.gov (United States)

de Souza, João Batista Freire; de Arruda, Alex Martins Varela; Domingos, Hérica Girlane Tertulino; de Macedo Costa, Leonardo Lelis

2013-05-01

The aim of this study was to evaluate the regional differences in the surface temperature of Naked Neck hens that were subjected to different temperatures in a semi-arid environment. The surface temperature was measured in four body regions (face, neck, legs and feathered area) of 60 Naked Neck hens. The following environmental variables were measured at the center of the shed: the black globe temperature (T G ), air temperature (T A ), wind speed (U) and relative humidity (R H ). The T A was divided into three classes: 1 (24.0-26.0 °C), 2 (26.1-28.9 °C) and 3 (29.0-31.0 °C). An analysis of variance was performed by the least squares method and a comparison of the means by the Tukey-Kramer test. The results showed a significant effect of T A class, the body region and the interaction between these two effects on the surface temperature. There was no significant difference between the T A classes for the face and neck. The legs and feathered area showed significant differences between the T A classes. Regarding the effect of body regions within each T A class, there was a significant difference among all regions in the three T A classes. In all T A classes the neck had the highest average followed by the face and legs. The feathered area showed the lowest average of the different T A classes. In conclusion, this study showed that there are regional differences in the surface temperature of Naked Neck hens, with the legs acting as thermal windows.

Study on electron density and average degree of ionization for the non-ideal argon plasmas

International Nuclear Information System (INIS)

Jing Ming; Huang Hua; Zhou Yisu; Wang Caixia

2008-01-01

Electron density and average degree of ionization of the non-ideal argon plasmas under different plasma temperature and density are calculated by using SHM model. It comes to a conclusion that the average degree of ionization is less than 0.5 for the non-ideal argon plasmas at temperature T=2.0eV and plasma density ρ=(0.01-0.5)g·cm -3 , and the average degree of ionization is reduced with the increase of plasma density ρ. This indicates that the non-ideal argon plasma has a very low degree of ionization so that most argon has not been ionized. In addition, the discussion on the ionization decrease with the increase of plasma density ρ is given. (authors)

Soil temperature of peatland landscapes as a factor in the development of exogenous processes of biogenic relief formation in engineering development of territory

Science.gov (United States)

Korkin, S.; Talyneva, O.; Kail, E.

2018-03-01

In the presented work we consider mire landscapes in the context of temperature monitoring. The mire landscapes in engineering development of the territory are very sensitive to anthropogenic impact that leads to a change in surface conditions, changes in natural succession and, as a rule, to changes in soil temperature and properties, which in turn may develop a complex of hostile geodynamic processes. For this study we used recording systems for field measurement of peat and subsoil temperatures. The measurements were made in two key areas: the territory of the north-taiga landscapes of Western Siberia (the Siberian Ridges), and the territory of the middle-taiga landscapes of Western Siberia (the Ob middle-river lowland). The paper analyses the data obtained from five observation sites (3, 5, 5a, 6 and 8) referred to hydromorphic landscapes. For the territory of the Siberian Ridges the 5-year average soil temperature was 3°C. For the Ob middle-river lowland the 6-year average soil temperature was 4.2°C. The annual soil temperature in the period 2015-2016 for Site 5a (man-disturbed area) was 8.3°C at all depths, which is 3.8°C higher than in a natural bog (Site 5 was a control area).

Fluoride concentration level in rural area in Poldasht city and daily fluoride intake based on drinking water consumption with temperature.

Science.gov (United States)

Mohammadi, Ali Akbar; Yousefi, Mahmood; Mahvi, Amir Hossein

2017-08-01

Long-term exposure to high level of fluoride can caused several adverse effects on human health including dental and skeletal fluorosis. We investigated all the drinking water source located in rural areas of Poldasht city, west Azerbaijan Province, North West Iran between 2014 and 2015. Fluoride concentration of water samples was measured by SPADNS method. We found that in the villages of Poldasht the average of fluoride concentration in drinking water sources (well, and the river) was in the range mg/l 0.28-10.23. The average daily received per 2 l of drinking water is in the range mg/l 0.7-16.6 per day per person. Drinking water demands cause fluorosis in the villages around the area residents and based on the findings of this study writers are announced suggestions below in order to take care of the health of area residents.

Stomatal conductance, canopy temperature, and leaf area index estimation using remote sensing and OBIA techniques

Science.gov (United States)

S. Panda; D.M. Amatya; G. Hoogenboom

2014-01-01

Remotely sensed images including LANDSAT, SPOT, NAIP orthoimagery, and LiDAR and relevant processing tools can be used to predict plant stomatal conductance (gs), leaf area index (LAI), and canopy temperature, vegetation density, albedo, and soil moisture using vegetation indices like normalized difference vegetation index (NDVI) or soil adjusted...

Prompt fission neutron spectra and average prompt neutron multiplicities

International Nuclear Information System (INIS)

Madland, D.G.; Nix, J.R.

1983-01-01

We present a new method for calculating the prompt fission neutron spectrum N(E) and average prompt neutron multiplicity anti nu/sub p/ as functions of the fissioning nucleus and its excitation energy. The method is based on standard nuclear evaporation theory and takes into account (1) the motion of the fission fragments, (2) the distribution of fission-fragment residual nuclear temperature, (3) the energy dependence of the cross section sigma/sub c/ for the inverse process of compound-nucleus formation, and (4) the possibility of multiple-chance fission. We use a triangular distribution in residual nuclear temperature based on the Fermi-gas model. This leads to closed expressions for N(E) and anti nu/sub p/ when sigma/sub c/ is assumed constant and readily computed quadratures when the energy dependence of sigma/sub c/ is determined from an optical model. Neutron spectra and average multiplicities calculated with an energy-dependent cross section agree well with experimental data for the neutron-induced fission of 235 U and the spontaneous fission of 252 Cf. For the latter case, there are some significant inconsistencies between the experimental spectra that need to be resolved. 29 references

Three-dimensional scanning force/tunneling spectroscopy at room temperature

International Nuclear Information System (INIS)

Sugimoto, Yoshiaki; Ueda, Keiichi; Abe, Masayuki; Morita, Seizo

2012-01-01

We simultaneously measured the force and tunneling current in three-dimensional (3D) space on the Si(111)-(7 × 7) surface using scanning force/tunneling microscopy at room temperature. The observables, the frequency shift and the time-averaged tunneling current were converted to the physical quantities of interest, i.e. the interaction force and the instantaneous tunneling current. Using the same tip, the local density of states (LDOS) was mapped on the same surface area at constant height by measuring the time-averaged tunneling current as a function of the bias voltage at every lateral position. LDOS images at negative sample voltages indicate that the tip apex is covered with Si atoms, which is consistent with the Si-Si covalent bonding mechanism for AFM imaging. A measurement technique for 3D force/current mapping and LDOS imaging on the equivalent surface area using the same tip was thus demonstrated. (paper)

Dynamic behaviour of bubbles of water vapour at a temperature lower than the boiling temperature

International Nuclear Information System (INIS)

Jansen, Franz

1966-01-01

This research thesis reports the study of the theoretical movement of the wall of vapour water bubbles in a sub-saturated boiling regime, i.e. with an average water temperature lower than the boiling temperature. While assuming that bubbles have an initial translational speed at the beginning of their condensation, the author shows that their shrinkage should result in an accelerated displacement in a direction normal to the wall and inward the liquid. Layers of hot water initially close to the wall would therefore be quickly transported towards cold water areas. Experiments allowed, in some cases, the acceleration of bubbles during their condensation to be noticed: for low sub-saturations in still water and for high sub-saturations in water in forced convection, even though, in this last case, the determination of accelerations is more delicate [fr

Stream temperature estimated in situ from thermal-infrared images: best estimate and uncertainty

International Nuclear Information System (INIS)

Iezzi, F; Todisco, M T

2015-01-01

The paper aims to show a technique to estimate in situ the stream temperature from thermal-infrared images deepening its best estimate and uncertainty. Stream temperature is an important indicator of water quality and nowadays its assessment is important particularly for thermal pollution monitoring in water bodies. Stream temperature changes are especially due to the anthropogenic heat input from urban wastewater and from water used as a coolant by power plants and industrial manufacturers. The stream temperatures assessment using ordinary techniques (e.g. appropriate thermometers) is limited by sparse sampling in space due to a spatial discretization necessarily punctual. Latest and most advanced techniques assess the stream temperature using thermal-infrared remote sensing based on thermal imagers placed usually on aircrafts or using satellite images. These techniques assess only the surface water temperature and they are suitable to detect the temperature of vast water bodies but do not allow a detailed and precise surface water temperature assessment in limited areas of the water body. The technique shown in this research is based on the assessment of thermal-infrared images obtained in situ via portable thermal imager. As in all thermographic techniques, also in this technique, it is possible to estimate only the surface water temperature. A stream with the presence of a discharge of urban wastewater is proposed as case study to validate the technique and to show its application limits. Since the technique analyzes limited areas in extension of the water body, it allows a detailed and precise assessment of the water temperature. In general, the punctual and average stream temperatures are respectively uncorrected and corrected. An appropriate statistical method that minimizes the errors in the average stream temperature is proposed. The correct measurement of this temperature through the assessment of thermal- infrared images obtained in situ via portable

Temperature response of the neuronal cytoskeleton mapped via atomic force and fluorescence microscopy

International Nuclear Information System (INIS)

Spedden, Elise; Staii, Cristian; Kaplan, David L

2013-01-01

Neuronal cells change their growth properties in response to external physical stimuli such as variations in external temperature, stiffness of the growth substrate, or topographical guidance cues. Detailed knowledge of the mechanisms that control these biomechanical responses is necessary for understanding the basic principles that underlie neuronal growth and regeneration. Here, we present elasticity maps of living cortical neurons (embryonic rat) as a function of temperature, and correlate these maps to the locations of internal structural components of the cytoskeleton. Neurons display a significant increase in the average elastic modulus upon a decrease in ambient temperature from 37 to 25 °C. We demonstrate that the dominant mechanism by which the elasticity of the neurons changes in response to temperature is the stiffening of the actin components of the cytoskeleton induced by myosin II. We also report a reversible shift in the location and composition of the high-stiffness areas of the neuron cytoskeleton with temperature. At 37 °C the areas of the cell displaying high elastic modulus overlap with the tubulin-dense regions, while at 25 °C these high-stiffness areas correspond to the actin-dense regions of the cytoskeleton. These results demonstrate the importance of considering temperature effects when investigating cytoskeletal dynamics in cells. (paper)

TEMPERATURE PREDICTION IN 3013 CONTAINERS IN K AREA MATERIAL STORAGE (KAMS) FACILITY USING REGRESSION METHODS

International Nuclear Information System (INIS)

Gupta, N

2008-01-01

3013 containers are designed in accordance with the DOE-STD-3013-2004. These containers are qualified to store plutonium (Pu) bearing materials such as PuO2 for 50 years. DOT shipping packages such as the 9975 are used to store the 3013 containers in the K-Area Material Storage (KAMS) facility at Savannah River Site (SRS). DOE-STD-3013-2004 requires that a comprehensive surveillance program be set up to ensure that the 3013 container design parameters are not violated during the long term storage. To ensure structural integrity of the 3013 containers, thermal analyses using finite element models were performed to predict the contents and component temperatures for different but well defined parameters such as storage ambient temperature, PuO 2 density, fill heights, weights, and thermal loading. Interpolation is normally used to calculate temperatures if the actual parameter values are different from the analyzed values. A statistical analysis technique using regression methods is proposed to develop simple polynomial relations to predict temperatures for the actual parameter values found in the containers. The analysis shows that regression analysis is a powerful tool to develop simple relations to assess component temperatures

The Effect of Tree Spacing and Size in Urban Areas: Strategies for Mitigating High Temperature in Urban Heat Islands

Science.gov (United States)

Berry, R.; Shandas, V.; Makido, Y.

2017-12-01

Many cities are unintentionally designed to be heat sinks, which absorb the sun's short-wave radiation and reemit as long-wave radiation. Long time reorganization of this `urban heat island' (UHI) phenomena has led researchers and city planners into developing strategies for reducing ambient temperatures through urban design. Specifically, greening areas have proven to reduce the temperature in UHI's, including strategies such as green streets, green facades, and green roofs have been implemented. Among the scientific community there is promoted study of how myriad greening strategies can reduce temperature, relatively limited work has focused on the distribution, density, and quantity of tree campaigns. This paper examines how the spacing and size of trees reduce temperatures differently. A major focus of the paper is to understand how to lower the temperature through tree planting, and provide recommendations to cities that are attempting to solve their own urban heat island issues. Because different cities have different room for planting greenery, we examined which strategies are more efficient given an area constraint. Areas that have less available room might not be able to plant a high density of trees. We compared the different experimental groups varying in density and size of trees against the control to see the effect the trees had. Through calibration with local weather stations, we used a micrometeorology program (ENVI-Met) to model and simulate the different experimental models and how they affect the temperature. The results suggest that some urban designs can reduce ambient temperatures by over 7 0C, and the inclusion of large form trees have the greatest contribution, by reducing temperatures over 15 0C. The results suggest that using specific strategies that combine placement of specific tree configurations with alternative distribution of urban development patterns can help to solve the current challenges of UHI's, and thereby support management

THE EFFECTS OF BUILT-UP AND GREEN AREAS ON THE LAND SURFACE TEMPERATURE OF THE KUALA LUMPUR CITY

Directory of Open Access Journals (Sweden)

N. A. Isa

2017-10-01

Full Text Available A common consequence of rapid and uncontrollable urbanization is Urban Heat Island (UHI. It occurs due to the negligence on climate behaviour which degrades the quality of urban climate condition. Recently, addressing urban climate in urban planning through mapping has received worldwide attention. Therefore, the need to identify the significant factors is a must. This study aims to analyse the relationships between Land Surface Temperature (LST and two urban parameters namely built-up and green areas. Geographical Information System (GIS and remote sensing techniques were used to prepare the necessary data layers required for this study. The built-up and the green areas were extracted from Landsat 8 satellite images either using the Normalized Difference Built-Up Index (NDBI, Normalized Difference Vegetation Index (NDVI or Modified Normalize Difference Water Index (MNDWI algorithms, while the mono-window algorithm was used to retrieve the Land Surface Temperature (LST. Correlation analysis and Multi-Linear Regression (MLR model were applied to quantitatively analyse the effects of the urban parameters. From the study, it was found that the two urban parameters have significant effects on the LST of Kuala Lumpur City. The built-up areas have greater influence on the LST as compared to the green areas. The built-up areas tend to increase the LST while green areas especially the densely vegetated areas help to reduce the LST within an urban areas. Future studies should focus on improving existing urban climatic model by including other urban parameters.

Soil organic carbon distribution in Mediterranean areas under a climate change scenario via multiple linear regression analysis.

Science.gov (United States)

Olaya-Abril, Alfonso; Parras-Alcántara, Luis; Lozano-García, Beatriz; Obregón-Romero, Rafael

2017-08-15

Over time, the interest on soil studies has increased due to its role in carbon sequestration in terrestrial ecosystems, which could contribute to decreasing atmospheric CO 2 rates. In many studies, independent variables were related to soil organic carbon (SOC) alone, however, the contribution degree of each variable with the experimentally determined SOC content were not considered. In this study, samples from 612 soil profiles were obtained in a natural protected (Red Natura 2000) of Sierra Morena (Mediterranean area, South Spain), considering only the topsoil 0-25cm, for better comparison between results. 24 independent variables were used to define it relationship with SOC content. Subsequently, using a multiple linear regression analysis, the effects of these variables on the SOC correlation was considered. Finally, the best parameters determined with the regression analysis were used in a climatic change scenario. The model indicated that SOC in a future scenario of climate change depends on average temperature of coldest quarter (41.9%), average temperature of warmest quarter (34.5%), annual precipitation (22.2%) and annual average temperature (1.3%). When the current and future situations were compared, the SOC content in the study area was reduced a 35.4%, and a trend towards migration to higher latitude and altitude was observed. Copyright © 2017 Elsevier B.V. All rights reserved.

Measurements of Heat-Transfer and Friction Coefficients for Helium Flowing in a Tube at Surface Temperatures up to 5900 Deg R

Science.gov (United States)

Taylor, Maynard F.; Kirchgessner, Thomas A.

1959-01-01

Measurements of average heat transfer and friction coefficients and local heat transfer coefficients were made with helium flowing through electrically heated smooth tubes with length-diameter ratios of 60 and 92 for the following range of conditions: Average surface temperature from 1457 to 4533 R, Reynolds numbe r from 3230 to 60,000, heat flux up to 583,200 Btu per hr per ft2 of heat transfer area, and exit Mach numbe r up to 1.0. The results indicate that, in the turbulent range of Reynolds number, good correlation of the local heat transfer coefficients is obtained when the physical properties and density of helium are evaluated at the surface temperature. The average heat transfer coefficients are best correlated on the basis that the coefficient varies with [1 + (L/D))(sup -0,7)] and that the physical properties and density are evaluated at the surface temperature. The average friction coefficients for the tests with no heat addition are in complete agreement with the Karman-Nikuradse line. The average friction coefficients for heat addition are in poor agreement with the accepted line.

Climate change and its impact on the Crn Drim Catchment Area In Macedonia

International Nuclear Information System (INIS)

Todorovik, Oliviia; Aleksovska, Nina; Rikaloska, Gorica

2004-01-01

In this paper it will be presented the overview of the climate change and climate regimes of the world in general according different scenarios in the latest assessment (the 3d Report published in 2001) of the Intergovernmental Panel on Climate Change (IPCC) and its impact on the Crn Drim catchment area in Macedonia.This analysis and interpretation only provides a preliminary investigation into climate change and how it will affect Ohrid and Prespa lake system as a part of Crn Drim catchment area, which is already attacked by the climate changed. From the climatological aspect two elements: temperature and rainfall, will be' calculated and their expected changes over the century in the same area. Dates used in these analyses are from the Hydro meteorological Service of Republic of Macedonia archives In the graphs are shown changes in average seasonal climate for the period around the 2080s, relative to 1961-1990 climate. Results are shown for the SRES A2 scenario, which assumes a future world of fairly conventional energy development, i.e., continuing dependence on fossil carbon fuels. The projections for average seasonal climate for temperature and precipitation are estimated and shown separately for two seasons: winter and summer. The estimated values are compared with annual mean global worming for the 2080s,-and for the SRES A2 scenario, as calculated by the IPCC (a value of about 3.2 o C). The results show rate of worming greater in summer than in winter for Ohrid Lake as well as for Prespa Lake. Concerning the precipitation, it increases slightly in winter and decreases substantially in summer, by around 30 per cent. As the conclusion it is obviously that the temperature will rise in all Crn Drim catchment area with implications for increasing water temperature and water quality, which would be degraded by higher water temperature. This will increase evaporation and as the results can be expected water level decreasing. Also, higher temperatures and heat

Spatial estimation of mean temperature and precipitation in areas of scarce meteorological information

Energy Technology Data Exchange (ETDEWEB)

Gomez, J.D. [Universidad Autonoma Chapingo, Chapingo (Mexico)]. E-mail: dgomez@correo.chapingo.mx; Etchevers, J.D. [Instituto de Recursos Naturales, Colegio de Postgraduados, Montecillo, Edo. de Mexico (Mexico); Monterroso, A.I. [departamento de Suelos, Universidad Autonoma Chapingo, Chapingo (Mexico); Gay, G. [Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico); Campo, J. [Instituto de Ecologia, Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico); Martinez, M. [Instituto de Recursos Naturales, Montecillo, Edo. de Mexico (Mexico)

2008-01-15

In regions of complex relief and scarce meteorological information it becomes difficult to implement techniques and models of numerical interpolation to elaborate reliable maps of climatic variables essential for the study of natural resources using the new tools of the geographic information systems. This paper presents a method for estimating annual and monthly mean values of temperature and precipitation, taking elements from simple interpolation methods and complementing them with some characteristics of more sophisticated methods. To determine temperature, simple linear regression equations were generated associating temperature with altitude of weather stations in the study region, which had been previously subdivided in accordance with humidity conditions and then applying such equations to the area's digital elevation model to obtain temperatures. The estimation of precipitation was based on the graphic method through the analysis of the meteorological systems that affect the regions of the study area throughout the year and considering the influence of mountain ridges on the movement of prevailing winds. Weather stations with data in nearby regions were analyzed according to their position in the landscape, exposure to humid winds, and false color associated with vegetation types. Weather station sites were used to reference the amount of rainfall; interpolation was attained using analogies with satellite images of false color to which a model of digital elevation was incorporated to find similar conditions within the study area. [Spanish] En las regiones de relieve complejo y con escasa informacion meteorologica se dificulta la aplicacion de las diferentes tecnicas y modelos de interpolacion numericos para elaborar mapas de variables climaticas confiables, indispensables para realizar estudios de los recursos naturales, con la utilizacion de las nuevas herramientas de los sistemas de informacion geografica. En este trabajo se presenta un metodo para

Up-to-date probabilistic temperature climatologies

International Nuclear Information System (INIS)

Krakauer, Nir Y; Devineni, Naresh

2015-01-01

With ongoing global warming, climatologies based on average past temperatures are increasingly recognized as imperfect guides for current conditions, yet there is no consensus on alternatives. Here, we compare several approaches to deriving updated expected values of monthly mean temperatures, including moving average, exponentially weighted moving average, and piecewise linear regression. We go beyond most previous work by presenting updated climate normals as probability distributions rather than only point estimates, enabling estimation of the changing likelihood of hot and cold extremes. We show that there is a trade-off between bias and variance in these approaches, but that bias can be mitigated by an additive correction based on a global average temperature series, which has much less interannual variability than a single-station series. Using thousands of monthly temperature time series from the Global Historical Climatology Network (GHCN), we find that the exponentially weighted moving average with a timescale of 15 years and global bias correction has good overall performance in hindcasting temperatures over the last 30 years (1984–2013) compared with the other methods tested. Our results suggest that over the last 30 years, the likelihood of extremely hot months (above the 99th percentile of the temperature probability distribution as of the early 1980s) has increased more than fourfold across the GHCN stations, whereas the likelihood of very cold months (under the 1st percentile) has decreased by over two-thirds. (letter)

Averaging models: parameters estimation with the R-Average procedure

Directory of Open Access Journals (Sweden)

S. Noventa

2010-01-01

Full Text Available The Functional Measurement approach, proposed within the theoretical framework of Information Integration Theory (Anderson, 1981, 1982, can be a useful multi-attribute analysis tool. Compared to the majority of statistical models, the averaging model can account for interaction effects without adding complexity. The R-Average method (Vidotto & Vicentini, 2007 can be used to estimate the parameters of these models. By the use of multiple information criteria in the model selection procedure, R-Average allows for the identification of the best subset of parameters that account for the data. After a review of the general method, we present an implementation of the procedure in the framework of R-project, followed by some experiments using a Monte Carlo method.

Computational prediction of the effective temperature in the lying area of pig pens

DEFF Research Database (Denmark)

Bjerg, Bjarne; Rong, Li; Zhang, Guoqiang

2018-01-01

Using solid floor instead of drained or slatted floor in the lying areas of pig pens has distinct advantages in relation to animal welfare, odour abatement and ammonia emission, energy consumption and reduced building costs. However, pig producers often opt out of providing a solid floor due......, individually contribute to the combined effect of the thermal condition raising pigs are exposed to. Computational Fluid Dynamics (CFD) simulations were conducted to estimate the relevant parameters and, finally, the ET. Furthermore, the developed ET equation was implemented in the CFD model as a Custom Field...... Function to calculate the distribution of ET in the animal occupied zone. It was assumed that a traditional diffuse ceiling air inlet would deliver the required airflow rate as long as the outdoor temperature was below 10. °C. At higher outdoor temperature, a ceiling-jet inlet above each pen was opened...

Comparison between core temperatures measured telemetrically using the CorTemp® ingestible temperature sensor and rectal temperature in healthy Labrador retrievers.

Science.gov (United States)

Osinchuk, Stephanie; Taylor, Susan M; Shmon, Cindy L; Pharr, John; Campbell, John

2014-10-01

This study evaluated the CorTemp(®) ingestible telemetric core body temperature sensor in dogs, to establish the relationship between rectal temperature and telemetrically measured core body temperature at rest and during exercise, and to examine the effect of sensor location in the gastrointestinal (GI) tract on measured core temperature. CorTemp(®) sensors were administered orally to fasted Labrador retriever dogs and radiographs were taken to document sensor location. Core and rectal temperatures were monitored throughout the day in 6 resting dogs and during a 10-minute strenuous retrieving exercise in 6 dogs. Time required for the sensor to leave the stomach (120 to 610 min) was variable. Measured core temperature was consistently higher than rectal temperature across all GI locations but temperature differences based on GI location were not significant (P = 0.5218). Resting dogs had a core temperature that was on average 0.4°C above their rectal temperature with 95% limits of agreement (LoA) between 1.2°C and -0.5°C. Core temperature in exercising dogs was on average 0.3°C higher than their concurrent rectal temperature, with LoA of +1.6°C and -1.1°C.

Numerical Simulation of Air Temperature and Velocity in a Naturally Ventilated Office

Directory of Open Access Journals (Sweden)

S. Shodiya

2017-04-01

Full Text Available This paper presents a numerical simulation of air velocity and air temperature distribution in an office room of Computer Engineering Department of University of Maiduguri which is naturally ventilated. The office room under investigation with the dimension 5 m × 5 m × 4 m has a door in the East direction, and two windows, one in the East direction and the other in the South direction. For cost effectiveness, numerical solutions of steady-state airflow and heat transfer were done using a complete two-dimensional model. The results showed that the windows and the door could not undertake indoor heat load that can make the occupants to be thermally comfortable. In activity area where people sit and stand, the air velocity is moderate, this is about 0.98 m/s on the average. In addition, the temperature in this area is relatively high of about 302 K (29 °C on the average. Based on the American Society of Heating, Refrigeration and Air-Conditioning Engineers (ASHRAE standard for comfort environment in summer (air temperature: 293 – 299 K (20 – 26 °C; air velocity: 0.5 – 0.8 m/s, the natural ventilation for the office room cannot give a thermal comfort for the inhabitant of the room. However, a window, if installed opposite the door could improve the ventilation of the office.

Association between temperature and maternal stress during pregnancy.

Science.gov (United States)

Lin, Yanfen; Hu, Wenjing; Xu, Jian; Luo, Zhongcheng; Ye, Xiaofang; Yan, Chonghuai; Liu, Zhiwei; Tong, Shilu

2017-10-01

Maternal psychological stress during pregnancy has essentially been conceptualized as a teratogen. However, little is known about the effect of temperature on maternal stress during pregnancy. The aim of this study is to investigate the relationship between temperature and maternal stress during pregnancy. In 2010, a total of 1931 eligible pregnant women were enrolled across Shanghai from four prenatal-care clinics during their mid-to-late pregnancy. Maternal life-event stress and emotional stress levels during pregnancy were assessed by the "Life Event Scale for Pregnant Women" (LESPW) and "Symptom Checklist-90-Revised Scale" (SCL-90-R), respectively. Exposure to ambient temperature was evaluated based on daily regional average in different moving average and lag days. The generalized estimating equations were used to evaluate the relationship between daily average temperature/temperature difference and maternal stress. After adjusting for relevant confounders, an U-shaped relationship was observed between daily average temperature and maternal Global-Severity-Index (GSI) of the SCL-90-R. Cumulative exposures to extremely low temperatures (stress during pregnancy. Copyright © 2017 Elsevier Inc. All rights reserved.

Quasi-analytical treatment of spatially averaged radiation transfer in complex terrain

Science.gov (United States)

LöWe, H.; Helbig, N.

2012-10-01

We provide a new quasi-analytical method to compute the subgrid topographic influences on the shortwave radiation fluxes and the effective albedo in complex terrain as required for large-scale meteorological, land surface, or climate models. We investigate radiative transfer in complex terrain via the radiosity equation on isotropic Gaussian random fields. Under controlled approximations we derive expressions for domain-averaged fluxes of direct, diffuse, and terrain radiation and the sky view factor. Domain-averaged quantities can be related to a type of level-crossing probability of the random field, which is approximated by long-standing results developed for acoustic scattering at ocean boundaries. This allows us to express all nonlocal horizon effects in terms of a local terrain parameter, namely, the mean-square slope. Emerging integrals are computed numerically, and fit formulas are given for practical purposes. As an implication of our approach, we provide an expression for the effective albedo of complex terrain in terms of the Sun elevation angle, mean-square slope, the area-averaged surface albedo, and the ratio of atmospheric direct beam to diffuse radiation. For demonstration we compute the decrease of the effective albedo relative to the area-averaged albedo in Switzerland for idealized snow-covered and clear-sky conditions at noon in winter. We find an average decrease of 5.8% and spatial patterns which originate from characteristics of the underlying relief. Limitations and possible generalizations of the method are discussed.

[Prediction model of meteorological grade of wheat stripe rust in winter-reproductive area, Sichuan Basin, China].

Science.gov (United States)

Guo, Xiang; Wang, Ming Tian; Zhang, Guo Zhi

2017-12-01

The winter reproductive areas of Puccinia striiformis var. striiformis in Sichuan Basin are often the places mostly affected by wheat stripe rust. With data on the meteorological condition and stripe rust situation at typical stations in the winter reproductive area in Sichuan Basin from 1999 to 2016, this paper classified the meteorological conditions inducing wheat stripe rust into 5 grades, based on the incidence area ratio of the disease. The meteorological factors which were biologically related to wheat stripe rust were determined through multiple analytical methods, and a meteorological grade model for forecasting wheat stripe rust was created. The result showed that wheat stripe rust in Sichuan Basin was significantly correlated with many meteorological factors, such as the ave-rage (maximum and minimum) temperature, precipitation and its anomaly percentage, relative humidity and its anomaly percentage, average wind speed and sunshine duration. Among these, the average temperature and the anomaly percentage of relative humidity were the determining factors. According to a historical retrospective test, the accuracy of the forecast based on the model was 64% for samples in the county-level test, and 89% for samples in the municipal-level test. In a meteorological grade forecast of wheat stripe rust in the winter reproductive areas in Sichuan Basin in 2017, the prediction was accurate for 62.8% of the samples, with 27.9% error by one grade and only 9.3% error by two or more grades. As a result, the model could deliver satisfactory forecast results, and predicate future wheat stripe rust from a meteorological point of view.

Estimation of sampling error uncertainties in observed surface air temperature change in China

Science.gov (United States)

Hua, Wei; Shen, Samuel S. P.; Weithmann, Alexander; Wang, Huijun

2017-08-01

This study examines the sampling error uncertainties in the monthly surface air temperature (SAT) change in China over recent decades, focusing on the uncertainties of gridded data, national averages, and linear trends. Results indicate that large sampling error variances appear at the station-sparse area of northern and western China with the maximum value exceeding 2.0 K2 while small sampling error variances are found at the station-dense area of southern and eastern China with most grid values being less than 0.05 K2. In general, the negative temperature existed in each month prior to the 1980s, and a warming in temperature began thereafter, which accelerated in the early and mid-1990s. The increasing trend in the SAT series was observed for each month of the year with the largest temperature increase and highest uncertainty of 0.51 ± 0.29 K (10 year)-1 occurring in February and the weakest trend and smallest uncertainty of 0.13 ± 0.07 K (10 year)-1 in August. The sampling error uncertainties in the national average annual mean SAT series are not sufficiently large to alter the conclusion of the persistent warming in China. In addition, the sampling error uncertainties in the SAT series show a clear variation compared with other uncertainty estimation methods, which is a plausible reason for the inconsistent variations between our estimate and other studies during this period.

The effect of interpolation methods in temperature and salinity trends in the Western Mediterranean

Directory of Open Access Journals (Sweden)

M. VARGAS-YANEZ

2012-04-01

Full Text Available Temperature and salinity data in the historical record are scarce and unevenly distributed in space and time and the estimation of linear trends is sensitive to different factors. In the case of the Western Mediterranean, previous works have studied the sensitivity of these trends to the use of bathythermograph data, the averaging methods or the way in which gaps in time series are dealt with. In this work, a new factor is analysed: the effect of data interpolation. Temperature and salinity time series are generated averaging existing data over certain geographical areas and also by means of interpolation. Linear trends from both types of time series are compared. There are some differences between both estimations for some layers and geographical areas, while in other cases the results are consistent. Those results which do not depend on the use of interpolated or non-interpolated data, neither are influenced by data analysis methods can be considered as robust ones. Those results influenced by the interpolation process or the factors analysed in previous sensitivity tests are not considered as robust results.

Temperature-monitored optical treatment for radial tissue expansion.

Science.gov (United States)

Bak, Jinoh; Kang, Hyun Wook

2017-07-01

Esophageal stricture occurs in 7-23% of patients with gastroesophageal reflux disease. However, the current treatments including stent therapy, balloon dilation, and bougienage involve limitations such as stent migration, formation of the new strictures, and snowplow effect. The purpose of the current study was to investigate the feasibility of structural expansion in tubular tissue ex vivo during temperature-monitored photothermal treatment with a diffusing applicator for esophageal stricture. Porcine liver was used as an ex vivo tissue sample for the current study. A glass tube was used to maintain a constant distance between the diffuser and tissue surface and to evaluate any variations in the luminal area after 10-W 1470-nm laser irradiation for potential stricture treatment. The 3D goniometer measurements confirmed roughly isotropic distribution with less than 10% deviation from the average angular intensity over 2π (i.e., 0.86 ± 0.09 in arbitrary unit) from the diffusing applicator. The 30-s irradiation increased the tissue temperature up to 72.5 °C, but due to temperature feedback, the interstitial tissue temperature became saturated at 70 °C (i.e., steady-state error = ±0.4 °C). The irradiation times longer than 5 s presented area expansion index of 1.00 ± 0.04, signifying that irreversible tissue denaturation permanently deformed the lumen in a circular shape and secured the equivalent luminal area to that of the glass tube. Application of a temperature feedback controller for photothermal treatment with the diffusing applicator can regulate the degree of thermal denaturation to feasibly treat esophageal stricture in a tubular tissue.

Average niche breadths of species in lake macrophyte communities respond to ecological gradients variably in four regions on two continents.

Science.gov (United States)

Alahuhta, Janne; Virtala, Antti; Hjort, Jan; Ecke, Frauke; Johnson, Lucinda B; Sass, Laura; Heino, Jani

2017-05-01

Different species' niche breadths in relation to ecological gradients are infrequently examined within the same study and, moreover, species niche breadths have rarely been averaged to account for variation in entire ecological communities. We investigated how average environmental niche breadths (climate, water quality and climate-water quality niches) in aquatic macrophyte communities are related to ecological gradients (latitude, longitude, altitude, species richness and lake area) among four distinct regions (Finland, Sweden and US states of Minnesota and Wisconsin) on two continents. We found that correlations between the three different measures of average niche breadths and ecological gradients varied considerably among the study regions, with average climate and average water quality niche breadth models often showing opposite trends. However, consistent patterns were also found, such as widening of average climate niche breadths and narrowing of average water quality niche breadths of aquatic macrophytes along increasing latitudinal and altitudinal gradients. This result suggests that macrophyte species are generalists in relation to temperature variations at higher latitudes and altitudes, whereas species in southern, lowland lakes are more specialised. In contrast, aquatic macrophytes growing in more southern nutrient-rich lakes were generalists in relation to water quality, while specialist species are adapted to low-productivity conditions and are found in highland lakes. Our results emphasise that species niche breadths should not be studied using only coarse-scale data of species distributions and corresponding environmental conditions, but that investigations on different kinds of niche breadths (e.g., climate vs. local niches) also require finer resolution data at broad spatial extents.

Associations between outdoor temperature and markers of inflammation: a cohort study

Directory of Open Access Journals (Sweden)

Zanobetti Antonella

2010-07-01

Full Text Available Abstract Background Associations between ambient temperature and cardiovascular mortality are well established. This study investigated whether inflammation could be part of the mechanism leading to temperature-related cardiovascular deaths. Methods The study population consisted of a cohort of 673 men with mean age of 74.6 years, living in the greater Boston area. They were seen for examination roughly every 4 years, and blood samples for inflammation marker analyses were drawn in 2000-2008 (total of 1254 visits. We used a mixed effects model to estimate the associations between ambient temperature and a variety of inflammation markers (C-reactive protein, white blood cell count, soluble Vascular Cell Adhesion Molecule-1, soluble Intercellular Adhesion Molecule-1, tumor necrosis factor alpha, and interleukins -1β, -6 and -8. Random intercept for each subject and several possible confounders, including combustion-related air pollution and ozone, were used in the models. Results We found a 0 to 1 day lagged and up to 4 weeks cumulative responses in C-reactive protein in association with temperature. We observed a 24.9% increase [95% Confidence interval (CI: 7.36, 45.2] in C-reactive protein for a 5°C decrease in the 4 weeks' moving average of temperature. We observed similar associations also between temperature and soluble Intercellular Adhesion Molecule-1 (4.52%, 95% CI: 1.05, 8.10, over 4 weeks' moving average, and between temperature and soluble Vascular Cell Adhesion Molecule-1 (6.60%, 95% CI: 1.31, 12.2 over 4 weeks' moving average. Penalized spline models showed no deviation from linearity. There were no associations between temperature and other inflammation markers. Conclusions Cumulative exposure to decreased temperature is associated with an increase in inflammation marker levels among elderly men. This suggests that inflammation markers are part of intermediate processes, which may lead to cold-, but not heat-, related

Implementation of large-scale average geostrophic wind shear in WAsP12.1

DEFF Research Database (Denmark)

Floors, Rogier Ralph; Troen, Ib; Kelly, Mark C.

The vertical extrapolation model described in the European Wind Atlas Troen and Petersen (1989) is modified to take into account large-scale average geostrophic wind shear to describe the effect of horizontal temperature gradients on the geostrophic wind. The method is implemented by extracting...... the average geostrophic wind shear from Climate Forecast System Reanalysis (CFSR) data and the values of nearest grid point are automatically used in the WAsP 12.1 user interface to provide better AEP predictions....

Diel hysteresis between soil respiration and soil temperature in a biological soil crust covered desert ecosystem.

Science.gov (United States)

Guan, Chao; Li, Xinrong; Zhang, Peng; Chen, Yongle

2018-01-01

Soil respiration induced by biological soil crusts (BSCs) is an important process in the carbon (C) cycle in arid and semi-arid ecosystems, where vascular plants are restricted by the harsh environment, particularly the limited soil moisture. However, the interaction between temperature and soil respiration remains uncertain because of the number of factors that control soil respiration, including temperature and soil moisture, especially in BSC-dominated areas. In this study, the soil respiration in moss-dominated crusts and lichen-dominated crusts was continuously measured using an automated soil respiration system over a one-year period from November 2015 to October 2016 in the Shapotou region of the Tengger Desert, northern China. The results indicated that over daily cycles, the half-hourly soil respiration rates in both types of BSC-covered areas were commonly related to the soil temperature. The observed diel hysteresis between the half-hourly soil respiration rates and soil temperature in the BSC-covered areas was limited by nonlinearity loops with semielliptical shapes, and soil temperature often peaked later than the half-hourly soil respiration rates in the BSC-covered areas. The average lag times between the half-hourly soil respiration rates and soil temperature for both types of BSC-covered areas were two hours over the diel cycles, and they were negatively and linearly related to the volumetric soil water content. Our results highlight the diel hysteresis phenomenon that occurs between soil respiration rates and soil temperatures in BSC-covered areas and the negative response of this phenomenon to soil moisture, which may influence total C budget evaluations. Therefore, the interactive effects of soil temperature and moisture on soil respiration in BSC-covered areas should be considered in global carbon cycle models of desert ecosystems.

Neutron resonance averaging

International Nuclear Information System (INIS)

Chrien, R.E.

1986-10-01

The principles of resonance averaging as applied to neutron capture reactions are described. Several illustrations of resonance averaging to problems of nuclear structure and the distribution of radiative strength in nuclei are provided. 30 refs., 12 figs

Heterotrophic respiration in drained tropical peat temperatures influenced by shading gradient

Science.gov (United States)

Jauhiainen, Jyrki; Kerojoki, Otto; Silvennoinen, Hanna; Limin, Suwido; Vasander, Harri

2015-04-01

Lowland peatlands in Southeast Asia constitute a highly concentrated carbon (C) pool of global significance. These peatlands have formed over periods of several millennia by forest vegetation tolerant to flooding and poor substrates. Uncontrollable drainage and reoccurring wild fires in lack of management after removal of forest cover has impaired the C-storing functions in large reclaimed areas. Intergovernmental Panel on Climate Change (IPCC) reporting sees drained tropical organic soils as one of the largest greenhouse gas emissions releasing terrestrial systems. Vast areas of deforested tropical peatlands do not receive noteworthy shading by vegetation, which increases the amount of solar radiation reaching the peat surface. We studied heterotrophic carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4) fluxes in tropical peat in conditions, where; (i) peat temperatures were modified by artificial shading (no shade, 28%, 51% and 90% from the full sun exposure), (ii) root respiration was minimized, (iii) nutrient availability for peat decomposer community was changed (NPK fertilization of 0 and 313 kg ha-1). The experiment was repeated at two over 20 years ago drained fallow agricultural- and degraded sites in Central Kalimantan, Indonesia. Enhanced shading created a lasting decrease in peat temperatures, and decreased diurnal temperature fluctuations, in comparison to less shaded plots. The largest peat temperature difference was between the unshaded and 90% shaded peat surface, where the average temperatures within the topmost 50-cm peat profile differed 3 °C, and diurnal temperatures at 5 cm depth varied up to 4.2 °C in the unshaded and 0.4 °C in the 90% shaded conditions. Highest impacts on the heterotrophic CO2 fluxes caused by the treatments were on agricultural land, where 90% shading from the full exposure resulted in a 33% lower CO2 emission average on the unfertilised plots and a 66% lower emission average on the fertilised plots. Correlation

LITERATURE REVIEW OF PUO2 CALCINATION TIME AND TEMPERATURE DATA FOR SPECIFIC SURFACE AREA

Energy Technology Data Exchange (ETDEWEB)

Daniel, G.

2012-03-06

The literature has been reviewed in December 2011 for calcination data of plutonium oxide (PuO{sub 2}) from plutonium oxalate Pu(C{sub 2}O{sub 4}){sub 2} precipitation with respect to the PuO{sub 2} specific surface area (SSA). A summary of the literature is presented for what are believed to be the dominant factors influencing SSA, the calcination temperature and time. The PuO{sub 2} from Pu(C{sub 2}O{sub 4}){sub 2} calcination data from this review has been regressed to better understand the influence of calcination temperature and time on SSA. Based on this literature review data set, calcination temperature has a bigger impact on SSA versus time. However, there is still some variance in this data set that may be reflecting differences in the plutonium oxalate preparation or different calcination techniques. It is evident from this review that additional calcination temperature and time data for PuO{sub 2} from Pu(C{sub 2}O{sub 4}){sub 2} needs to be collected and evaluated to better define the relationship. The existing data set has a lot of calcination times that are about 2 hours and therefore may be underestimating the impact of heating time on SSA. SRNL recommends that more calcination temperature and time data for PuO{sub 2} from Pu(C{sub 2}O{sub 4}){sub 2} be collected and this literature review data set be augmented to better refine the relationship between PuO{sub 2} SSA and its calcination parameters.

Low-Temperature Sol-Gel Synthesis of Nitrogen-Doped Anatase/Brookite Biphasic Nanoparticles with High Surface Area and Visible-Light Performance

Directory of Open Access Journals (Sweden)

Liang Jiang

2017-12-01

Full Text Available Nitrogen doping in combination with the brookite phase or a mixture of TiO2 polymorphs nanomaterials can enhance photocatalytic activity under visible light. Generally, nitrogen-dopedanatase/brookite mixed phases TiO2 nanoparticles obtained by hydrothermal or solvothermal method need to be at high temperature and with long time heating treatment. Furthermore, the surface areas of them are low (<125 m2/g. There is hardly a report on the simple and direct preparation of N-doped anatase/brookite mixed phase TiO2 nanostructures using sol-gel method at low heating temperature. In this paper, the nitrogen-doped anatase/brookite biphasic nanoparticles with large surface area (240 m2/g were successfully prepared using sol-gel method at low temperature (165 °C, and with short heating time (4 h under autogenous pressure. The obtained sample without subsequent annealing at elevated temperatures showed enhanced photocatalytic efficiency for the degradation of methyl orange (MO with 4.2-, 9.6-, and 7.5-fold visible light activities compared to P25 and the amorphous samples heated in muffle furnace with air or in tube furnace with a flow of nitrogen at 165 °C, respectively. This result was attributed to the synergistic effects of nitrogen doping, mixed crystalline phases, and high surface area.

Optimization of low temperature solar thermal electric generation with Organic Rankine Cycle in different areas

International Nuclear Information System (INIS)

Jing, Li; Gang, Pei; Jie, Ji

2010-01-01

The presented low temperature solar thermal electric generation system mainly consists of compound parabolic concentrators (CPC) and the Organic Rankine Cycle (ORC) working with HCFC-123. A novel design is proposed to reduce heat transfer irreversibility between conduction oil and HCFC-123 in the heat exchangers while maintaining the stability of electricity output. Mathematical formulations are developed to study the heat transfer and energy conversion processes and the numerical simulation is carried out based on distributed parameters. Annual performances of the proposed system in different areas of Canberra, Singapore, Bombay, Lhasa, Sacramento and Berlin are simulated. The influences of the collector tilt angle adjustment, the connection between the heat exchangers and the CPC collectors, and the ORC evaporation temperature on the system performance are investigated. The results indicate that the three factors have a major impact on the annual electricity output and should be the key points of optimization. And the optimized system shows that: (1) The annual received direct irradiance can be significantly increased by two or three times optimal adjustments even when the CPC concentration ratio is smaller than 3.0. (2) Compared with the traditional single-stage collectors, two-stage collectors connected with the heat exchangers by two thermal oil cycles can improve the collector efficiency by 8.1-20.9% in the simultaneous processes of heat collection and power generation. (3) On the use of the market available collectors the optimal ORC evaporation temperatures in most of the simulated areas are around 120 C. (author)

Response of Respiration of Soybean Leaves Grown at Ambient and Elevated Carbon Dioxide Concentrations to Day-to-day Variation in Light and Temperature under Field Conditions

Science.gov (United States)

BUNCE, JAMES A.

2005-01-01

• Background and Aims Respiration is an important component of plant carbon balance, but it remains uncertain how respiration will respond to increases in atmospheric carbon dioxide concentration, and there are few measurements of respiration for crop plants grown at elevated [CO2] under field conditions. The hypothesis that respiration of leaves of soybeans grown at elevated [CO2] is increased is tested; and the effects of photosynthesis and acclimation to temperature examined. • Methods Net rates of carbon dioxide exchange were recorded every 10 min, 24 h per day for mature upper canopy leaves of soybeans grown in field plots at the current ambient [CO2] and at ambient plus 350 µmol mol−1 [CO2] in open top chambers. Measurements were made on pairs of leaves from both [CO2] treatments on a total of 16 d during the middle of the growing seasons of two years. • Key Results Elevated [CO2] increased daytime net carbon dioxide fixation rates per unit of leaf area by an average of 48 %, but had no effect on night-time respiration expressed per unit of area, which averaged 53 mmol m−2 d−1 (1·4 µmol m−2 s−1) for both the ambient and elevated [CO2] treatments. Leaf dry mass per unit of area was increased on average by 23 % by elevated [CO2], and respiration per unit of mass was significantly lower at elevated [CO2]. Respiration increased by a factor of 2·5 between 18 and 26 °C average night temperature, for both [CO2] treatments. • Conclusions These results do not support predictions that elevated [CO2] would increase respiration per unit of area by increasing photosynthesis or by increasing leaf mass per unit of area, nor the idea that acclimation of respiration to temperature would be rapid enough to make dark respiration insensitive to variation in temperature between nights. PMID:15781437

Supersymmetry at finite temperature

International Nuclear Information System (INIS)

Clark, T.E.; Love, S.T.

1983-01-01

Finite-temperature supersymmetry (SUSY) is characterized by unbroken Ward identities for SUSY variations of ensemble averages of Klein-operator inserted imaginary time-ordered products of fields. Path-integral representations of these products are defined and the Feynman rules in superspace are given. The finite-temperature no-renormalization theorem is derived. Spontaneously broken SUSY at zero temperature is shown not to be restored at high temperature. (orig.)

Geothermal gradients in Iraqi Kurdistan deduced from bottom hole temperatures

Directory of Open Access Journals (Sweden)

Rzger A. Abdula

2017-09-01

Full Text Available Bottom hole temperature (BHT data from 12 oil wells in Iraqi Kurdistan were used to obtain the thermal trend of Iraqi Kurdistan. Due to differences in thermal conductivity of rocks and groundwater movement, variations in geothermal gradients were observed. The highest geothermal gradient (29.2 °C/km was found for well Taq Taq-8 in the Low Folded Zone (central part of the area. The lowest geothermal gradients (14.9 °C/km were observed for well Bekhme-1 in the High Folded Zone (northern and northeastern parts of the area. The average regional geothermal gradient for Iraqi Kurdistan is 21 °C/km.

Averaging processes in granular flows driven by gravity

Science.gov (United States)

Rossi, Giulia; Armanini, Aronne

2016-04-01

One of the more promising theoretical frames to analyse the two-phase granular flows is offered by the similarity of their rheology with the kinetic theory of gases [1]. Granular flows can be considered a macroscopic equivalent of the molecular case: the collisions among molecules are compared to the collisions among grains at a macroscopic scale [2,3]. However there are important statistical differences in dealing with the two applications. In the two-phase fluid mechanics, there are two main types of average: the phasic average and the mass weighed average [4]. The kinetic theories assume that the size of atoms is so small, that the number of molecules in a control volume is infinite. With this assumption, the concentration (number of particles n) doesn't change during the averaging process and the two definitions of average coincide. This hypothesis is no more true in granular flows: contrary to gases, the dimension of a single particle becomes comparable to that of the control volume. For this reason, in a single realization the number of grain is constant and the two averages coincide; on the contrary, for more than one realization, n is no more constant and the two types of average lead to different results. Therefore, the ensamble average used in the standard kinetic theory (which usually is the phasic average) is suitable for the single realization, but not for several realization, as already pointed out in [5,6]. In the literature, three main length scales have been identified [7]: the smallest is the particles size, the intermediate consists in the local averaging (in order to describe some instability phenomena or secondary circulation) and the largest arises from phenomena such as large eddies in turbulence. Our aim is to solve the intermediate scale, by applying the mass weighted average, when dealing with more than one realizations. This statistical approach leads to additional diffusive terms in the continuity equation: starting from experimental

Trajectory averaging for stochastic approximation MCMC algorithms

KAUST Repository

Liang, Faming

2010-10-01

The subject of stochastic approximation was founded by Robbins and Monro [Ann. Math. Statist. 22 (1951) 400-407]. After five decades of continual development, it has developed into an important area in systems control and optimization, and it has also served as a prototype for the development of adaptive algorithms for on-line estimation and control of stochastic systems. Recently, it has been used in statistics with Markov chain Monte Carlo for solving maximum likelihood estimation problems and for general simulation and optimizations. In this paper, we first show that the trajectory averaging estimator is asymptotically efficient for the stochastic approximation MCMC (SAMCMC) algorithm under mild conditions, and then apply this result to the stochastic approximation Monte Carlo algorithm [Liang, Liu and Carroll J. Amer. Statist. Assoc. 102 (2007) 305-320]. The application of the trajectory averaging estimator to other stochastic approximationMCMC algorithms, for example, a stochastic approximation MLE algorithm for missing data problems, is also considered in the paper. © Institute of Mathematical Statistics, 2010.

[Ichthyoplankton from the pier area in Limón, Costa Rica].

Science.gov (United States)

Dominici-Arosemena, A; Brugnoli-Olivera, E; Solano-Ulate, S; Molina-Ureña, H; Ramírez Coghi, A R

2000-01-01

Four sampling stations were set 200-500 m off Limon Port, Costa Rica, at an average depth of 20 m. From October 1996 to May 1997 horizontal subsuperficial trawls were done for 12 minutes at a speed of about 2 Km/h, with a 1,000 microns plancton net. A total of 28 samples were processed and 104 physical-chemistry parameter measurements were taken. Average salinity was 30.1 +/- 3.7 and dissolved oxygen 6.9 +/- 0.6 mg l-1 reflecting good aeration throughout the sampling period. This suggests good mixture and a highly dynamic hydrography. Temperature showed no drastic variations (28.0 +/- 1.7 degrees C), possibly because of the constant mixing with shallow water. The highest larval counts were for November and early January and include families common to reefs and estuaries (Balistidae, Lutjanidae) and to coastal areas (Centropomidae, Gerreidae, Haemulidae, Carangidae, Engraulidae, Hemiramphidae, and representative Pleuronectiformes) existing in a common area.

Influence of Cooling Rate in High-Temperature Area on Hardening of Deposited High-Cutting Chrome-Tungsten Metal

OpenAIRE

Malushin, N. N.; Valuev, Denis Viktorovich; Valueva, Anna Vladimirovna; Serikbol, A.; Borovikov, I. F.

2015-01-01

The authors study the influence of cooling rate in high-temperature area for thermal cycle of high-cutting chrome-tungsten metal weld deposit on the processes of carbide phase merging and austenite grain growth for the purpose of providing high hardness of deposited metal (HRC 64-66).

Finite Temperature Lattice QCD with GPUs

International Nuclear Information System (INIS)

Cardoso, N.; Cardoso, M.; Bicudo, P.

2011-01-01

Graphics Processing Units (GPUs) are being used in many areas of physics, since the performance versus cost is very attractive. The GPUs can be addressed by CUDA which is a NVIDIA's parallel computing architecture. It enables dramatic increases in computing performance by harnessing the power of the GPU. We present a performance comparison between the GPU and CPU with single precision and double precision in generating lattice SU(2) configurations. Analyses with single and multiple GPUs, using CUDA and OPENMP, are also presented. We also present SU(2) results for the renormalized Polyakov loop, colour averaged free energy and the string tension as a function of the temperature. (authors)

Amplification and dampening of soil respiration by changes in temperature variability

Directory of Open Access Journals (Sweden)

C. A. Sierra

2011-04-01

Full Text Available Accelerated release of carbon from soils is one of the most important feedbacks related to anthropogenically induced climate change. Studies addressing the mechanisms for soil carbon release through organic matter decomposition have focused on the effect of changes in the average temperature, with little attention to changes in temperature variability. Anthropogenic activities are likely to modify both the average state and the variability of the climatic system; therefore, the effects of future warming on decomposition should not only focus on trends in the average temperature, but also variability expressed as a change of the probability distribution of temperature. Using analytical and numerical analyses we tested common relationships between temperature and respiration and found that the variability of temperature plays an important role determining respiration rates of soil organic matter. Changes in temperature variability, without changes in the average temperature, can affect the amount of carbon released through respiration over the long-term. Furthermore, simultaneous changes in the average and variance of temperature can either amplify or dampen the release of carbon through soil respiration as climate regimes change. These effects depend on the degree of convexity of the relationship between temperature and respiration and the magnitude of the change in temperature variance. A potential consequence of this effect of variability would be higher respiration in regions where both the mean and variance of temperature are expected to increase, such as in some low latitude regions; and lower amounts of respiration where the average temperature is expected to increase and the variance to decrease, such as in northern high latitudes.

Amplification and dampening of soil respiration by changes in temperature variability

Science.gov (United States)

Sierra, C.A.; Harmon, M.E.; Thomann, E.; Perakis, S.S.; Loescher, H.W.

2011-01-01

Accelerated release of carbon from soils is one of the most important feed backs related to anthropogenically induced climate change. Studies addressing the mechanisms for soil carbon release through organic matter decomposition have focused on the effect of changes in the average temperature, with little attention to changes in temperature vari-ability. Anthropogenic activities are likely to modify both the average state and the variability of the climatic system; therefore, the effects of future warming on decomposition should not only focus on trends in the average temperature, but also variability expressed as a change of the probability distribution of temperature.Using analytical and numerical analyses we tested common relationships between temperature and respiration and found that the variability of temperature plays an important role determining respiration rates of soil organic matter. Changes in temperature variability, without changes in the average temperature, can affect the amount of carbon released through respiration over the long term. Furthermore, simultaneous changes in the average and variance of temperature can either amplify or dampen there release of carbon through soil respiration as climate regimes change. The effects depend on the degree of convexity of the relationship between temperature and respiration and the magnitude of the change in temperature variance. A potential consequence of this effect of variability would be higher respiration in regions where both the mean and variance of temperature are expected to increase, such as in some low latitude regions; and lower amounts of respiration where the average temperature is expected to increase and the variance to decrease, such as in northern high latitudes.

Improving Shade Modelling in a Regional River Temperature Model Using Fine-Scale LIDAR Data

Science.gov (United States)

Hannah, D. M.; Loicq, P.; Moatar, F.; Beaufort, A.; Melin, E.; Jullian, Y.

2015-12-01

Air temperature is often considered as a proxy of the stream temperature to model the distribution areas of aquatic species water temperature is not available at a regional scale. To simulate the water temperature at a regional scale (105 km²), a physically-based model using the equilibrium temperature concept and including upstream-downstream propagation of the thermal signal was developed and applied to the entire Loire basin (Beaufort et al., submitted). This model, called T-NET (Temperature-NETwork) is based on a hydrographical network topology. Computations are made hourly on 52,000 reaches which average 1.7 km long in the Loire drainage basin. The model gives a median Root Mean Square Error of 1.8°C at hourly time step on the basis of 128 water temperature stations (2008-2012). In that version of the model, tree shadings is modelled by a constant factor proportional to the vegetation cover on 10 meters sides the river reaches. According to sensitivity analysis, improving the shade representation would enhance T-NET accuracy, especially for the maximum daily temperatures, which are currently not very well modelized. This study evaluates the most efficient way (accuracy/computing time) to improve the shade model thanks to 1-m resolution LIDAR data available on tributary of the LoireRiver (317 km long and an area of 8280 km²). Two methods are tested and compared: the first one is a spatially explicit computation of the cast shadow for every LIDAR pixel. The second is based on averaged vegetation cover characteristics of buffers and reaches of variable size. Validation of the water temperature model is made against 4 temperature sensors well spread along the stream, as well as two airborne thermal infrared imageries acquired in summer 2014 and winter 2015 over a 80 km reach. The poster will present the optimal length- and crosswise scale to characterize the vegetation from LIDAR data.

Adaptation of model proteins from cold to hot environments involves continuous and small adjustments of average parameters related to amino acid composition.

Science.gov (United States)

De Vendittis, Emmanuele; Castellano, Immacolata; Cotugno, Roberta; Ruocco, Maria Rosaria; Raimo, Gennaro; Masullo, Mariorosario

2008-01-07

The growth temperature adaptation of six model proteins has been studied in 42 microorganisms belonging to eubacterial and archaeal kingdoms, covering optimum growth temperatures from 7 to 103 degrees C. The selected proteins include three elongation factors involved in translation, the enzymes glyceraldehyde-3-phosphate dehydrogenase and superoxide dismutase, the cell division protein FtsZ. The common strategy of protein adaptation from cold to hot environments implies the occurrence of small changes in the amino acid composition, without altering the overall structure of the macromolecule. These continuous adjustments were investigated through parameters related to the amino acid composition of each protein. The average value per residue of mass, volume and accessible surface area allowed an evaluation of the usage of bulky residues, whereas the average hydrophobicity reflected that of hydrophobic residues. The specific proportion of bulky and hydrophobic residues in each protein almost linearly increased with the temperature of the host microorganism. This finding agrees with the structural and functional properties exhibited by proteins in differently adapted sources, thus explaining the great compactness or the high flexibility exhibited by (hyper)thermophilic or psychrophilic proteins, respectively. Indeed, heat-adapted proteins incline toward the usage of heavier-size and more hydrophobic residues with respect to mesophiles, whereas the cold-adapted macromolecules show the opposite behavior with a certain preference for smaller-size and less hydrophobic residues. An investigation on the different increase of bulky residues along with the growth temperature observed in the six model proteins suggests the relevance of the possible different role and/or structure organization played by protein domains. The significance of the linear correlations between growth temperature and parameters related to the amino acid composition improved when the analysis was

Environmental pollution due to gas flaring at Oyigbo area of Rivers State

International Nuclear Information System (INIS)

Avwiri, G. O.; Ebeniro, J. O.

1996-01-01

Environmental degradation due to oil activities in the oil rich Niger Delta of Nigeria is daily approaching a non-tolerance level. Pollutants come from various aspects of operation ranging from seismic operations through drilling to the refinery stage. Gas flared daily by Oil Companies constitute a major health hazard in this country. Environmental pollution due to gas flaring at Oyigbo area of Rivers State is hereby reported. Surface temperature-distance variations were investigated for both dry (March) and rainy (June) seasons. Physical and chemical properties of the rainwater from the areas were also measured and analysed. The results show a surface temperature elevation of about 4.1 Celsius above the mean normal diurnal temperature within a 3.00 km. radius. An average pH 4.25 was recorded thus showing the acidic nature of the environmental rainwater from the area. All other measured parameters showed serious deviations from standards. This temperature elevation and increased acidity of the rainwater have enormous influence on socio-economic lives and the activities of the populace especially on their source of income which is mainly small scale farming. It is therefore necessary that Government agencies empowered to monitor environment especially FEPA should implement all the existing legislation on gas flaring and be more involved in the design and location of gas flaring stacks. These stacks should be located at least 2 km. from towns and villages

Impacts of rising air temperatures on electric transmission ampacity and peak electricity load in the United States

Science.gov (United States)

Bartos, Matthew; Chester, Mikhail; Johnson, Nathan; Gorman, Brandon; Eisenberg, Daniel; Linkov, Igor; Bates, Matthew

2016-11-01

Climate change may constrain future electricity supply adequacy by reducing electric transmission capacity and increasing electricity demand. The carrying capacity of electric power cables decreases as ambient air temperatures rise; similarly, during the summer peak period, electricity loads typically increase with hotter air temperatures due to increased air conditioning usage. As atmospheric carbon concentrations increase, higher ambient air temperatures may strain power infrastructure by simultaneously reducing transmission capacity and increasing peak electricity load. We estimate the impacts of rising ambient air temperatures on electric transmission ampacity and peak per-capita electricity load for 121 planning areas in the United States using downscaled global climate model projections. Together, these planning areas account for roughly 80% of current peak summertime load. We estimate climate-attributable capacity reductions to transmission lines by constructing thermal models of representative conductors, then forcing these models with future temperature projections to determine the percent change in rated ampacity. Next, we assess the impact of climate change on electricity load by using historical relationships between ambient temperature and utility-scale summertime peak load to estimate the extent to which climate change will incur additional peak load increases. We find that by mid-century (2040-2060), increases in ambient air temperature may reduce average summertime transmission capacity by 1.9%-5.8% relative to the 1990-2010 reference period. At the same time, peak per-capita summertime loads may rise by 4.2%-15% on average due to increases in ambient air temperature. In the absence of energy efficiency gains, demand-side management programs and transmission infrastructure upgrades, these load increases have the potential to upset current assumptions about future electricity supply adequacy.

Associations between air temperature and cardio-respiratory mortality in the urban area of Beijing, China: a time-series analysis

OpenAIRE

Liu, Liqun; Breitner, Susanne; Pan, Xiaochuan; Franck, Ulrich; Leitte, Arne Marian; Wiedensohler, Alfred; von Klot, Stephanie; Wichmann, H-Erich; Peters, Annette; Schneider, Alexandra

2011-01-01

Abstract Background Associations between air temperature and mortality have been consistently observed in Europe and the United States; however, there is a lack of studies for Asian countries. Our study investigated the association between air temperature and cardio-respiratory mortality in the urban area of Beijing, China. Methods Death counts for cardiovascular and respiratory diseases for adult residents (≥15 years), meteorological parameters and concentrations of particulate air pollution...

Future climate and wildfire: ecosystem projections of area burned in the western US

Science.gov (United States)

Littell, J. S.; Duffy, P.; Battisti, D. S.; McKenzie, D.; Peterson, D. L.

2010-12-01

The area burned by fire in ecosystems of the western United States has been closely linked to climate in the paleoecological record and in the modern record. Statistical models of area burned show that the climatic controls on area burned vary with vegetation type (Littell et al. 2009). In more arid or systems (grasslands, shrublands, woodlands), antecedent climatic controls on fire were associated first with the production of fuels and secondarily with drought in the year of fire. These relationships typically manifested as wetter and sometimes cooler conditions in the seasons prior to the fire season. Area burned in forest ecosystems and some woodlands was primarily associated with drought conditions, specifically increased temperature and decreased precipitation in the year of fire and the seasons leading up to the fire season. These climatic controls indicate the role of climate in drying existing fuels. Statistical fire models trained on the late 20th century for ecoprovinces in the West would be useful for projecting area burned, at least until vegetation type conversion driven by climate and disturbance occurs. To that end, we used ~ 2.5 degree gridded future climate fields derived for a multi-GCM ensemble of 1C and 2C temperature increase forcing to develop future ecoprovince monthly and seasonal average temperature and associated precipitation and used these as predictors in statistical fire models of future projected area burned. We also conducted modeling scenarios with the ensemble temperature increase paired with historical precipitation. Most ecoprovinces had increases in area burned, with a range of ~ 67% to over 600% . Ecoprovinces that are primarily sensitive to precipitation changes exhibit smaller increases than those most sensitive to temperature (forest systems). We also developed exceedance probabilities. Some ecoprovinces show large increases in area burned but low exceedance probabilities, suggest that the area burned is concentrated more

Influence of Cooling Rate in High-Temperature Area on Hardening of Deposited High-Cutting Chrome-Tungsten Metal

International Nuclear Information System (INIS)

Malushin, N N; Valuev, D V; Valueva, A V; Serikbol, A; Borovikov, I F

2015-01-01

The authors study the influence of cooling rate in high-temperature area for thermal cycle of high-cutting chrome-tungsten metal weld deposit on the processes of carbide phase merging and austenite grain growth for the purpose of providing high hardness of deposited metal (HRC 64-66). (paper)

An axially averaged-radial transport model of tokamak edge plasmas

International Nuclear Information System (INIS)

Prinja, A.K.; Conn, R.W.

1984-01-01

A two-zone axially averaged-radial transport model for edge plasmas is described that incorporates parallel electron and ion conduction, localized recycling, parallel electron pressure gradient effects and sheath losses. Results for high recycling show that the radial electron temperature profile is determined by parallel electron conduction over short radial distances (proportional 3 cm). At larger radius where Tsub(e) has fallen appreciably, convective transport becomes equally important. The downstream density and ion temperature profiles are very flat over the region where electron conduction dominates. This is seen to result from a sharply decaying velocity profile that follows the radial electron temperature. A one-dimensional analytical recycling model shows that at high neutral pumping rates, the plasma density at the plate, nsub(ia), scales linearly with the unperturbed background density, nsub(io). When ionization dominates nsub(ia)/nsub(io) proportional exp(nsub(io)) while in the intermediate regime nsub(ia)/nsub(io) proportional exp(proportional nsub(io)). Such behavior is qualitatively in accord with experimental observations. (orig.)

The Hengill geothermal area, Iceland: variation of temperature gradients deduced from the maximum depth of seismogenesis

Science.gov (United States)

Foulger, G.R.

1995-01-01

Given a uniform lithology and strain rate and a full seismic data set, the maximum depth of earthquakes may be viewed to a first order as an isotherm. These conditions are approached at the Hengill geothermal area, S. Iceland, a dominantly basaltic area. The temperature at which seismic failure ceases for the strain rates likely at the Hengill geothermal area is determined by analogy with oceanic crust, and is about 650 ?? 50??C. The topographies of the top and bottom of the seismogenic layer were mapped using 617 earthquakes. The thickness of the seismogenic layer is roughly constant and about 3 km. A shallow, aseismic, low-velocity volume within the spreading plate boundary that crosses the area occurs above the top of the seismogenic layer and is interpreted as an isolated body of partial melt. The base of the seismogenic layer has a maximum depth of about 6.5 km beneath the spreading axis and deepens to about 7 km beneath a transform zone in the south of the area. -from Author

Fine resolution 3D temperature fields off Kerguelen from instrumented penguins

Science.gov (United States)

Charrassin, Jean-Benoît; Park, Young-Hyang; Le Maho, Yvon; Bost, Charles-André

2004-12-01

The use of diving animals as autonomous vectors of oceanographic instruments is rapidly increasing, because this approach yields cost-efficient new information and can be used in previously poorly sampled areas. However, methods for analyzing the collected data are still under development. In particular, difficulties may arise from the heterogeneous data distribution linked to animals' behavior. Here we show how raw temperature data collected by penguin-borne loggers were transformed to a regular gridded dataset that provided new information on the local circulation off Kerguelen. A total of 16 king penguins ( Aptenodytes patagonicus) were equipped with satellite-positioning transmitters and with temperature-time-depth recorders (TTDRs) to record dive depth and sea temperature. The penguins' foraging trips recorded during five summers ranged from 140 to 600 km from the colony and 11,000 dives >100 m were recorded. Temperature measurements recorded during diving were used to produce detailed 3D temperature fields of the area (0-200 m). The data treatment included dive location, determination of the vertical profile for each dive, averaging and gridding of those profiles onto 0.1°×0.1° cells, and optimal interpolation in both the horizontal and vertical using an objective analysis. Horizontal fields of temperature at the surface and 100 m are presented, as well as a vertical section along the main foraging direction of the penguins. Compared to conventional temperature databases (Levitus World Ocean Atlas and historical stations available in the area), the 3D temperature fields collected from penguins are extremely finely resolved, by one order finer. Although TTDRs were less accurate than conventional instruments, such a high spatial resolution of penguin-derived data provided unprecedented detailed information on the upper level circulation pattern east of Kerguelen, as well as the iron-enrichment mechanism leading to a high primary production over the Kerguelen

Evaluation of soft x-ray average recombination coefficient and average charge for metallic impurities in beam-heated plasmas

International Nuclear Information System (INIS)

Sesnic, S.S.; Bitter, M.; Hill, K.W.; Hiroe, S.; Hulse, R.; Shimada, M.; Stratton, B.; von Goeler, S.

1986-05-01

The soft x-ray continuum radiation in TFTR low density neutral beam discharges can be much lower than its theoretical value obtained by assuming a corona equilibrium. This reduced continuum radiation is caused by an ionization equilibrium shift toward lower states, which strongly changes the value of the average recombination coefficient of metallic impurities anti γ, even for only slight changes in the average charge, anti Z. The primary agent for this shift is the charge exchange between the highly ionized impurity ions and the neutral hydrogen, rather than impurity transport, because the central density of the neutral hydrogen is strongly enhanced at lower plasma densities with intense beam injection. In the extreme case of low density, high neutral beam power TFTR operation (energetic ion mode) the reduction in anti γ can be as much as one-half to two-thirds. We calculate the parametric dependence of anti γ and anti Z for Ti, Cr, Fe, and Ni impurities on neutral density (equivalent to beam power), electron temperature, and electron density. These values are obtained by using either a one-dimensional impurity transport code (MIST) or a zero-dimensional code with a finite particle confinement time. As an example, we show the variation of anti γ and anti Z in different TFTR discharges

Interfacial area measurements in two-phase flow

International Nuclear Information System (INIS)

Veteau, J.-M.

1979-08-01

A thorough understanding of two-phase flow requires the accurate measurement of the time-averaged interfacial area per unit volume (also called the time-averaged integral specific area). The so-called 'specific area' can be estimated by several techniques described in the literature. These different methods are reviewed and the flow conditions which lead to a rigourous determination of the time-averaged integral specific area are clearly established. The probe technique, involving local measurements seems very attractive because of its large range of application [fr

Temporal relation between temperature change and FDG uptake in brown adipose tissue

International Nuclear Information System (INIS)

Kim, SunHee; Krynyckyi, Borys R.; Machac, Josef; Kim, Chun K.

2008-01-01

It has been reported that the prevalence of 18 F fluorodeoxyglucose (FDG) uptake in brown adipose tissue (BAT) is related to outdoor temperature, i.e., more frequent during the colder periods of the year. The purpose of this study was to assess the temporal relationship between BAT FDG uptake and temperature. We correlated the prevalence of BAT with average temperatures (divided into five temperature ranges) of seven different durations. One thousand four hundred ninety-five consecutive FDG Positron emission tomography (PET) studies in 1,159 patients (566 male and 593 female, mean age = 60.4 years) were retrospectively reviewed. FDG uptake with distinct patterns compatible with BAT was identified by a consensus of two readers. The local daily average temperature from January 2000 to November 2003 (beginning 60 days before the date of first PET scan) were obtained, and 2-, 3-, 7-, 14-, 30-, and 60-day average temperatures before the date of a PET study were calculated. The prevalence of BAT FDG uptake was correlated with these various average temperatures. The daily, 2-day, 3-day, and 7-day average temperature had an inverse relation with the prevalence of BAT, i.e., the lower the temperature, the higher prevalence of BAT. When the temperature was averaged over 14 days or longer, this inverse relationship between the temperature and the prevalence of BAT was no longer preserved. Our data suggest that increased FDG uptake in BAT occurs more often as an acute response to cold weather (1-7 days) rather than to prolonged periods of average cold weather. (orig.)

Potential breeding distributions of U.S. birds predicted with both short-term variability and long-term average climate data.

Science.gov (United States)

Bateman, Brooke L; Pidgeon, Anna M; Radeloff, Volker C; Flather, Curtis H; VanDerWal, Jeremy; Akçakaya, H Resit; Thogmartin, Wayne E; Albright, Thomas P; Vavrus, Stephen J; Heglund, Patricia J

2016-12-01

Climate conditions, such as temperature or precipitation, averaged over several decades strongly affect species distributions, as evidenced by experimental results and a plethora of models demonstrating statistical relations between species occurrences and long-term climate averages. However, long-term averages can conceal climate changes that have occurred in recent decades and may not capture actual species occurrence well because the distributions of species, especially at the edges of their range, are typically dynamic and may respond strongly to short-term climate variability. Our goal here was to test whether bird occurrence models can be predicted by either covariates based on short-term climate variability or on long-term climate averages. We parameterized species distribution models (SDMs) based on either short-term variability or long-term average climate covariates for 320 bird species in the conterminous USA and tested whether any life-history trait-based guilds were particularly sensitive to short-term conditions. Models including short-term climate variability performed well based on their cross-validated area-under-the-curve AUC score (0.85), as did models based on long-term climate averages (0.84). Similarly, both models performed well compared to independent presence/absence data from the North American Breeding Bird Survey (independent AUC of 0.89 and 0.90, respectively). However, models based on short-term variability covariates more accurately classified true absences for most species (73% of true absences classified within the lowest quarter of environmental suitability vs. 68%). In addition, they have the advantage that they can reveal the dynamic relationship between species and their environment because they capture the spatial fluctuations of species potential breeding distributions. With this information, we can identify which species and guilds are sensitive to climate variability, identify sites of high conservation value where climate

Low-Cost Wireless Temperature Measurement: Design, Manufacture, and Testing of a PCB-Based Wireless Passive Temperature Sensor.

Science.gov (United States)

Yan, Dan; Yang, Yong; Hong, Yingping; Liang, Ting; Yao, Zong; Chen, Xiaoyong; Xiong, Jijun

2018-02-10

Low-cost wireless temperature measurement has significant value in the food industry, logistics, agriculture, portable medical equipment, intelligent wireless health monitoring, and many areas in everyday life. A wireless passive temperature sensor based on PCB (Printed Circuit Board) materials is reported in this paper. The advantages of the sensor include simple mechanical structure, convenient processing, low-cost, and easiness in integration. The temperature-sensitive structure of the sensor is a dielectric-loaded resonant cavity, consisting of the PCB substrate. The sensitive structure also integrates a patch antenna for the transmission of temperature signals. The temperature sensing mechanism of the sensor is the dielectric constant of the PCB substrate changes with temperature, which causes the resonant frequency variation of the resonator. Then the temperature can be measured by detecting the changes in the sensor's working frequency. The PCB-based wireless passive temperature sensor prototype is prepared through theoretical design, parameter analysis, software simulation, and experimental testing. The high- and low-temperature sensing performance of the sensor is tested, respectively. The resonant frequency decreases from 2.434 GHz to 2.379 GHz as the temperature increases from -40 °C to 125 °C. The fitting curve proves that the experimental data have good linearity. Three repetitive tests proved that the sensor possess well repeatability. The average sensitivity is 347.45 KHz / ℃ from repetitive measurements conducted three times. This study demonstrates the feasibility of the PCB-based wireless passive sensor, which provides a low-cost temperature sensing solution for everyday life, modern agriculture, thriving intelligent health devices, and so on, and also enriches PCB product lines and applications.

Temperature-related mortality estimates after accounting for the cumulative effects of air pollution in an urban area.

Science.gov (United States)

Stanišić Stojić, Svetlana; Stanišić, Nemanja; Stojić, Andreja

2016-07-11

To propose a new method for including the cumulative mid-term effects of air pollution in the traditional Poisson regression model and compare the temperature-related mortality risk estimates, before and after including air pollution data. The analysis comprised a total of 56,920 residents aged 65 years or older who died from circulatory and respiratory diseases in Belgrade, Serbia, and daily mean PM10, NO2, SO2 and soot concentrations obtained for the period 2009-2014. After accounting for the cumulative effects of air pollutants, the risk associated with cold temperatures was significantly lower and the overall temperature-attributable risk decreased from 8.80 to 3.00 %. Furthermore, the optimum range of temperature, within which no excess temperature-related mortality is expected to occur, was very broad, between -5 and 21 °C, which differs from the previous findings that most of the attributable deaths were associated with mild temperatures. These results suggest that, in polluted areas of developing countries, most of the mortality risk, previously attributed to cold temperatures, can be explained by the mid-term effects of air pollution. The results also showed that the estimated relative importance of PM10 was the smallest of four examined pollutant species, and thus, including PM10 data only is clearly not the most effective way to control for the effects of air pollution.

Contribution to forecast of environmental impact, in the long run, for fuel cells of low and average temperature using the Delphi methodology

International Nuclear Information System (INIS)

Ribeiro, Maria Alice Morato; Oliveira, Wagner dos Santos

2007-01-01

Assessing future energy systems is of major importance for providing information on potential environmental awareness of some life cycle stages of innovative technologies, for determining competitive advantages compared to conventional technologies and for developing scenarios of future. Today, intense activity of R and D in cells is verified in fuel cells, practiced in centers of research, university, and laboratories of great companies, what it seems to indicate the use in wide scale of these generating right-handers of energy, before long. The work has a main objective, in the long run, to make a forecast of the environmental impact of low and average temperature fuel cells, analyzing all the stages of their useful life and final disposal of the materials that constitute them, using the Delphi methodology. The results of the environmental impact evaluation of the main materials used in the stacks are presented, considering their manufacture, operation and final disposal after their useful life ends. (author)

Estimation of average annual streamflows and power potentials for Alaska and Hawaii

Energy Technology Data Exchange (ETDEWEB)

Verdin, Kristine L. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Idaho National Engineering and Environmental Lab. (INEEL)

2004-05-01

This paper describes the work done to develop average annual streamflow estimates and power potential for the states of Alaska and Hawaii. The Elevation Derivatives for National Applications (EDNA) database was used, along with climatic datasets, to develop flow and power estimates for every stream reach in the EDNA database. Estimates of average annual streamflows were derived using state-specific regression equations, which were functions of average annual precipitation, precipitation intensity, drainage area, and other elevation-derived parameters. Power potential was calculated through the use of the average annual streamflow and the hydraulic head of each reach, which is calculated from the EDNA digital elevation model. In all, estimates of streamflow and power potential were calculated for over 170,000 stream segments in the Alaskan and Hawaiian datasets.

Retrieval of air temperatures from crowd-sourced battery temperatures of cell phones

Science.gov (United States)

Overeem, Aart; Robinson, James; Leijnse, Hidde; Uijlenhoet, Remko; Steeneveld, Gert-Jan; Horn, Berthold K. P.

2013-04-01

Accurate air temperature observations are important for urban meteorology, for example to study the urban heat island and adverse effects of high temperatures on human health. The number of available temperature observations is often relatively limited. A new development is presented to derive temperature information for the urban canopy from an alternative source: cell phones. Battery temperature data were collected by users of an Android application for cell phones (opensignal.com). The application automatically sends battery temperature data to a server for storage. In this study, battery temperatures are averaged in space and time to obtain daily averaged battery temperatures for each city separately. A regression model, which can be related to a physical model, is employed to retrieve daily air temperatures from battery temperatures. The model is calibrated with observed air temperatures from a meteorological station of an airport located in or near the city. Time series of air temperatures are obtained for each city for a period of several months, where 50% of the data is for independent verification. Results are presented for Buenos Aires, London, Los Angeles, Paris, Mexico City, Moscow, Rome, and Sao Paulo. The evolution of the retrieved air temperatures often correspond well with the observed ones. The mean absolute error of daily air temperatures is less than 2 degrees Celsius, and the bias is within 1 degree Celsius. This shows that monitoring air temperatures employing an Android application holds great promise. Since 75% of the world's population has a cell phone, 20% of the land surface of the earth has cellular telephone coverage, and 500 million devices use the Android operating system, there is a huge potential for measuring air temperatures employing cell phones. This could eventually lead to real-time world-wide temperature maps.

Low-Temperature Preparation of Tungsten Oxide Anode Buffer Layer via Ultrasonic Spray Pyrolysis Method for Large-Area Organic Solar Cells.

Science.gov (United States)

Ji, Ran; Zheng, Ding; Zhou, Chang; Cheng, Jiang; Yu, Junsheng; Li, Lu

2017-07-18

Tungsten oxide (WO₃) is prepared by a low-temperature ultrasonic spray pyrolysis method in air atmosphere, and it is used as an anode buffer layer (ABL) for organic solar cells (OSCs). The properties of the WO₃ transition metal oxide material as well as the mechanism of ultrasonic spray pyrolysis processes are investigated. The results show that the ultrasonic spray pyrolysized WO₃ ABL exhibits low roughness, matched energy level, and high conductivity, which results in high charge transport efficiency and suppressive recombination in OSCs. As a result, compared to the OSCs based on vacuum thermal evaporated WO₃, a higher power conversion efficiency of 3.63% is reached with low-temperature ultrasonic spray pyrolysized WO₃ ABL. Furthermore, the mostly spray-coated OSCs with large area was fabricated, which has a power conversion efficiency of ~1%. This work significantly enhances our understanding of the preparation and application of low temperature-processed WO₃, and highlights the potential of large area, all spray coated OSCs for sustainable commercial fabrication.

Crowdsourcing urban air temperatures from smartphone battery temperatures

NARCIS (Netherlands)

Overeem, A.; Robinson, J.C.R.; Leijnse, H.; Steeneveld, G.J.; Horn, B.K.P.; Uijlenhoet, R.

2013-01-01

[1] Accurate air temperature observations in urban areas are important for meteorology and energy demand planning. They are indispensable to study the urban heat island effect and the adverse effects of high temperatures on human health. However, the availability of temperature observations in

On Averaging Rotations

DEFF Research Database (Denmark)

Gramkow, Claus

1999-01-01

In this article two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very offten the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belo...... approximations to the Riemannian metric, and that the subsequent corrections are inherient in the least squares estimation. Keywords: averaging rotations, Riemannian metric, matrix, quaternion......In this article two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very offten the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...

A novel dual-functional MEMS sensor integrating both pressure and temperature units

Energy Technology Data Exchange (ETDEWEB)

Chen Tao; Zhang Zhaohua; Ren Tianling; Miao Gujin; Zhou Changjian; Lin Huiwang; Liu Litian, E-mail: RenTL@tsinghua.edu.c [National Laboratory for Information Science and Technology, Institute of Microelectronics, Tsinghua University, Beijing 100084 (China)

2010-07-15

This paper proposes a novel miniature dual-functional sensor integrating both pressure and temperature sensitive units on a single chip. The device wafer of SOI is used as a pizeoresistive diaphragm which features excellent consistency in thickness. The conventional anisotropic wet etching has been abandoned, while ICP etching has been employed to etch out the reference cave to minimize the area of individual device in the way that the 57.4{sup 0} slope has been eliminated. As a result, the average cost of the single chip is reduced. Two PN junctions with constant ratio of the areas of depletion regions have also been integrated on the same chip to serve as a temperature sensor, and each PN junction shows high linearity over -40 to 100 {sup 0}C and low power consumption. The iron implanting process for PN junction is exactly compatible with the piezoresistor, with no additional expenditure. The pressure sensitivity is 86 mV/MPa, while temperature sensitivity is 1.43 mV/{sup 0}C, both complying with the design objective.

A novel dual-functional MEMS sensor integrating both pressure and temperature units

International Nuclear Information System (INIS)

Chen Tao; Zhang Zhaohua; Ren Tianling; Miao Gujin; Zhou Changjian; Lin Huiwang; Liu Litian

2010-01-01

This paper proposes a novel miniature dual-functional sensor integrating both pressure and temperature sensitive units on a single chip. The device wafer of SOI is used as a pizeoresistive diaphragm which features excellent consistency in thickness. The conventional anisotropic wet etching has been abandoned, while ICP etching has been employed to etch out the reference cave to minimize the area of individual device in the way that the 57.4 0 slope has been eliminated. As a result, the average cost of the single chip is reduced. Two PN junctions with constant ratio of the areas of depletion regions have also been integrated on the same chip to serve as a temperature sensor, and each PN junction shows high linearity over -40 to 100 0 C and low power consumption. The iron implanting process for PN junction is exactly compatible with the piezoresistor, with no additional expenditure. The pressure sensitivity is 86 mV/MPa, while temperature sensitivity is 1.43 mV/ 0 C, both complying with the design objective.

Irreversibility and self-organization in spin glasses. 2. Irreversibility and the problem of configuration averaging

International Nuclear Information System (INIS)

Kovrov, V.P.; Kurbatov, A.M.

1989-05-01

The generalization of a configuration averaging to a system displaying irreversible effects is suggested. The properties of the ''pathological'' equilibrium state at low temperatures are determined and discussed. (author). 16 refs, 3 figs

Average-energy games

Directory of Open Access Journals (Sweden)

Patricia Bouyer

2015-09-01

Full Text Available Two-player quantitative zero-sum games provide a natural framework to synthesize controllers with performance guarantees for reactive systems within an uncontrollable environment. Classical settings include mean-payoff games, where the objective is to optimize the long-run average gain per action, and energy games, where the system has to avoid running out of energy. We study average-energy games, where the goal is to optimize the long-run average of the accumulated energy. We show that this objective arises naturally in several applications, and that it yields interesting connections with previous concepts in the literature. We prove that deciding the winner in such games is in NP inter coNP and at least as hard as solving mean-payoff games, and we establish that memoryless strategies suffice to win. We also consider the case where the system has to minimize the average-energy while maintaining the accumulated energy within predefined bounds at all times: this corresponds to operating with a finite-capacity storage for energy. We give results for one-player and two-player games, and establish complexity bounds and memory requirements.

Analysis of the relationship between the monthly temperatures and weather types in Iberian Peninsula

Science.gov (United States)

Peña Angulo, Dhais; Trigo, Ricardo; Nicola, Cortesi; José Carlos, González-Hidalgo

2016-04-01

In this study, the relationship between the atmospheric circulation and weather types and the monthly average maximum and minimum temperatures in the Iberian Peninsula is modeled (period 1950-2010). The temperature data used were obtained from a high spatial resolution (10km x 10km) dataset (MOTEDAS dataset, Gonzalez-Hidalgo et al., 2015a). In addition, a dataset of Portuguese temperatures was used (obtained from the Portuguese Institute of Sea and Atmosphere). The weather type classification used was the one developed by Jenkinson and Collison, which was adapted for the Iberian Peninsula by Trigo and DaCamara (2000), using Sea Level Pressure data from NCAR/NCEP Reanalysis dataset (period 1951-2010). The analysis of the behaviour of monthly temperatures based on the weather types was carried out using a stepwise regression procedure of type forward to estimate temperatures in each cell of the considered grid, for each month, and for both maximum and minimum monthly average temperatures. The model selects the weather types that best estimate the temperatures. From the validation model it was obtained the error distribution in the time (months) and space (Iberian Peninsula). The results show that best estimations are obtained for minimum temperatures, during the winter months and in coastal areas. González-Hidalgo J.C., Peña-Angulo D., Brunetti M., Cortesi, C. (2015a): MOTEDAS: a new monthly temperature database for mainland Spain and the trend in temperature (1951-2010). International Journal of Climatology 31, 715-731. DOI: 10.1002/joc.4298

The impact of temperature changes on summer time ozone and its precursors in the Eastern Mediterranean

Directory of Open Access Journals (Sweden)

U. Im

2011-04-01

Full Text Available Changes in temperature due to variability in meteorology and climate change are expected to significantly impact atmospheric composition. The Mediterranean is a climate sensitive region and includes megacities like Istanbul and large urban agglomerations such as Athens. The effect of temperature changes on gaseous air pollutant levels and the atmospheric processes that are controlling them in the Eastern Mediterranean are here investigated. The WRF/CMAQ mesoscale modeling system is used, coupled with the MEGAN model for the processing of biogenic volatile organic compound emissions. A set of temperature perturbations (spanning from 1 to 5 K is applied on a base case simulation corresponding to July 2004. The results indicate that the Eastern Mediterranean basin acts as a reservoir of pollutants and their precursor emissions from large urban agglomerations. During summer, chemistry is a major sink at these urban areas near the surface, and a minor contributor at downwind areas. On average, the atmospheric processes are more effective within the first 1000 m above ground. Temperature increases lead to increases in biogenic emissions by 9±3% K⁻¹. Ozone mixing ratios increase almost linearly with the increases in ambient temperatures by 1±0.1 ppb O₃ K⁻¹ for all studied urban and receptor stations except for Istanbul, where a 0.4±0.1 ppb O₃ K⁻¹ increase is calculated, which is about half of the domain-averaged increase of 0.9±0.1 ppb O₃ K⁻¹. The computed changes in atmospheric processes are also linearly related with temperature changes.

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Dome Reef, 2007 (NODC Accession 0093023)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Wellwood, 2006 - 2009 (NODC Accession 0093067)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at 7-mile Bridge (NODC Accession 0002750)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Heat stress in urban areas. Indoor and outdoor temperatures in different urban structure types and subjectively reported well-being during a heat wave in the city of Leipzig

Energy Technology Data Exchange (ETDEWEB)

Franck, Ulrich; Roeder, Stefan; Schlink, Uwe [Helmholtz Centre for Environmental Research - UFZ, Leipzig (Germany). Core Facility Studies; Krueger, Michael [Leipzig Univ. (Germany). Inst. of Geography; Schwarz, Nina [Helmholtz Centre for Environmental Research - UFZ, Leipzig (Germany). Dept. of Computational Landscape Ecology; Grossmann, Katrin [Helmholtz Centre for Environmental Research - UFZ, Leipzig (Germany). Dept. of Urban and Environmental Sociology

2013-04-15

Climate projections for Leipzig suggest elevated minimum and maximum temperatures as well as more frequent days with high temperatures. Hence, climate change is threatening human well-being and health. People spend the majority of their time indoors. Therefore, indoor temperatures (especially during the night) are of special importance with respect to well-being and health. Indoor air temperature depends on outdoor air temperatures, but is for example modified by type of urban structure, housing area, and may be also influenced by differences in the behavior of the inhabitants. Especially in cities, outdoor air temperatures depend on urban structure e.g. housing density, building arrangement, unpaved areas, types of urban structures, urban green, and other factors. Hence, the questions arise how types of urban structures are related to inner-urban temperature differences and how outdoor air temperatures influence indoor temperatures in dependence on urban housing conditions. This work is a part of a pilot study conducted during the summer 2010 which gathered data from remote sensing, mobile measurements, stationary measurements of air temperatures and relative humidity in areas with different housing structures, and of indoor as well as outdoor temperatures in occupied apartments. Household-survey data reported the subjective perception of heat stress. The study resulted in rather complex relationships between type of housing areas, indoor and outdoor temperatures, morning and evening temperatures, indoor and outdoor temperatures as well as subjective heat perception. Green spaces and types of residential areas are related to air temperatures. More green resulted in lower temperatures. Temperatures have a tendency to increase with increasing story number and are significantly higher in the top floor. An indoor heat island effect corresponding to the outdoor effect could be shown for the homes: Distance to city center is a predicting variable for both outdoor and

Heat stress in urban areas: Indoor and outdoor temperatures in different urban structure types and subjectively reported well-being during a heat wave in the city of Leipzig

Directory of Open Access Journals (Sweden)

Ulrich Franck

2013-04-01

Full Text Available Climate projections for Leipzig suggest elevated minimum and maximum temperatures as well as more frequent days with high temperatures. Hence, climate change is threatening human well-being and health. People spend the majority of their time indoors. Therefore, indoor temperatures (especially during the night are of special importance with respect to well-being and health. Indoor air temperature depends on outdoor air temperatures, but is for example modified by type of urban structure, housing area, and may be also influenced by differences in the behavior of the inhabitants. Especially in cities, outdoor air temperatures depend on urban structure e.g. housing density, building arrangement, unpaved areas, types of urban structures, urban green, and other factors. Hence, the questions arise how types of urban structures are related to inner-urban temperature differences and how outdoor air temperatures influence indoor temperatures in dependence on urban housing conditions. This work is a part of a pilot study conducted during the summer 2010 which gathered data from remote sensing, mobile measurements, stationary measurements of air temperatures and relative humidity in areas with different housing structures, and of indoor as well as outdoor temperatures in occupied apartments. Household-survey data reported the subjective perception of heat stress. The study resulted in rather complex relationships between type of housing areas, indoor and outdoor temperatures, morning and evening temperatures, indoor and outdoor temperatures as well as subjective heat perception. Green spaces and types of residential areas are related to air temperatures. More green resulted in lower temperatures. Temperatures have a tendency to increase with increasing story number and are significantly higher in the top floor. An indoor heat island effect corresponding to the outdoor effect could be shown for the homes: Distance to city center is a predicting variable for

Ground-water temperature of the Wyoming quadrangle in central Delaware : with application to ground-water-source heat pumps

Science.gov (United States)

Hodges, Arthur L.

1982-01-01

Ground-water temperature was measured during a one-year period (1980-81) in 20 wells in the Wyoming Quadrangle in central Delaware. Data from thermistors set at fixed depths in two wells were collected twice each week, and vertical temperature profiles of the remaining 18 wells were made monthly. Ground-water temperature at 8 feet below land surface in well Jc55-1 ranged from 45.0 degrees F in February to 70.1 degrees F in September. Temperature at 35 feet below land surface in the same well reached a minimum of 56.0 degrees F in August, and a maximum of 57.8 degrees F in February. Average annual temperature of ground water at 25 feet below land surface in all wells ranged from 54.6 degrees F to 57.8 degrees F. Variations of average temperature probably reflect the presence or absence of forestation in the recharge areas of the wells. Ground-water-source heat pumps supplied with water from wells 30 or more feet below land surface will operate more efficiently in both heating and cooling modes than those supplied with water from shallower depths. (USGS)

Coherent changes of wintertime surface air temperatures over North Asia and North America.

Science.gov (United States)

Yu, Bin; Lin, Hai

2018-03-29

The surface temperature variance and its potential change with global warming are most prominent in winter over Northern Hemisphere mid-high latitudes. Consistent wintertime surface temperature variability has been observed over large areas in Eurasia and North America on a broad range of time scales. However, it remains a challenge to quantify where and how the coherent change of temperature anomalies occur over the two continents. Here we demonstrate the coherent change of wintertime surface temperature anomalies over North Asia and the central-eastern parts of North America for the period from 1951 to 2015. This is supported by the results from the empirical orthogonal function analysis of surface temperature and temperature trend anomalies over the Northern Hemisphere extratropical lands and the timeseries analysis of the regional averaged temperature anomalies over North Asia and the Great Plains and Great Lakes. The Asian-Bering-North American (ABNA) teleconnection provides a pathway to connect the regional temperature anomalies over the two continents. The ABNA is also responsible for the decadal variation of the temperature relationship between North Asia and North America.

Influences of climate change on area variation of Qinghai Lake on Qinghai-Tibetan Plateau since 1980s.

Science.gov (United States)

Tang, Lingyi; Duan, Xiaofang; Kong, Fanjin; Zhang, Fan; Zheng, Yangfan; Li, Zhen; Mei, Yi; Zhao, Yanwen; Hu, Shuijin

2018-05-09

Qinghai-Tibetan Plateau is the most sensitive region to global warming on Earth. Qinghai Lake, the largest lake on the plateau, has experienced evident area variation during the past several decades. To quantify the area changes of Qinghai Lake, a satellite-based survey based on Landsat images from the 1980s to 2010s has been performed. In addition, meteorological data from all the seven available stations on Qinghai-Tibetan Plateau has been analyzed. Area of Qinghai Lake shrank ~2% during 1987-2005, and then increased ~3% from 2005-2016. Meanwhile, the average annual temperature increased 0.319 °C/10 y in the past 50 years, where the value is 0.415 °C/10 y from 2005-2016. The structural equation modeling (SEM) shows that precipitation is the primary factor influencing the area of Qinghai Lake. Moreover, temperature might be tightly correlated with precipitation, snow line, and evaporation, thereby indirectly causes alternations of the lake area. This study elucidated the significant area variation of water body on the Qinghai-Tibetan Plateau under global warming since 1980s.

Body segment differences in surface area, skin temperature and 3D displacement and the estimation of heat balance during locomotion in hominins.

Science.gov (United States)

Cross, Alan; Collard, Mark; Nelson, Andrew

2008-06-18

The conventional method of estimating heat balance during locomotion in humans and other hominins treats the body as an undifferentiated mass. This is problematic because the segments of the body differ with respect to several variables that can affect thermoregulation. Here, we report a study that investigated the impact on heat balance during locomotion of inter-segment differences in three of these variables: surface area, skin temperature and rate of movement. The approach adopted in the study was to generate heat balance estimates with the conventional method and then compare them with heat balance estimates generated with a method that takes into account inter-segment differences in surface area, skin temperature and rate of movement. We reasoned that, if the hypothesis that inter-segment differences in surface area, skin temperature and rate of movement affect heat balance during locomotion is correct, the estimates yielded by the two methods should be statistically significantly different. Anthropometric data were collected on seven adult male volunteers. The volunteers then walked on a treadmill at 1.2 m/s while 3D motion capture cameras recorded their movements. Next, the conventional and segmented methods were used to estimate the volunteers' heat balance while walking in four ambient temperatures. Lastly, the estimates produced with the two methods were compared with the paired t-test. The estimates of heat balance during locomotion yielded by the two methods are significantly different. Those yielded by the segmented method are significantly lower than those produced by the conventional method. Accordingly, the study supports the hypothesis that inter-segment differences in surface area, skin temperature and rate of movement impact heat balance during locomotion. This has important implications not only for current understanding of heat balance during locomotion in hominins but also for how future research on this topic should be approached.

Body segment differences in surface area, skin temperature and 3D displacement and the estimation of heat balance during locomotion in hominins.

Directory of Open Access Journals (Sweden)

Alan Cross

Full Text Available The conventional method of estimating heat balance during locomotion in humans and other hominins treats the body as an undifferentiated mass. This is problematic because the segments of the body differ with respect to several variables that can affect thermoregulation. Here, we report a study that investigated the impact on heat balance during locomotion of inter-segment differences in three of these variables: surface area, skin temperature and rate of movement. The approach adopted in the study was to generate heat balance estimates with the conventional method and then compare them with heat balance estimates generated with a method that takes into account inter-segment differences in surface area, skin temperature and rate of movement. We reasoned that, if the hypothesis that inter-segment differences in surface area, skin temperature and rate of movement affect heat balance during locomotion is correct, the estimates yielded by the two methods should be statistically significantly different. Anthropometric data were collected on seven adult male volunteers. The volunteers then walked on a treadmill at 1.2 m/s while 3D motion capture cameras recorded their movements. Next, the conventional and segmented methods were used to estimate the volunteers' heat balance while walking in four ambient temperatures. Lastly, the estimates produced with the two methods were compared with the paired t-test. The estimates of heat balance during locomotion yielded by the two methods are significantly different. Those yielded by the segmented method are significantly lower than those produced by the conventional method. Accordingly, the study supports the hypothesis that inter-segment differences in surface area, skin temperature and rate of movement impact heat balance during locomotion. This has important implications not only for current understanding of heat balance during locomotion in hominins but also for how future research on this topic should be

Changing surface-atmosphere energy exchange and refreezing capacity of the lower accumulation area, West Greenland

Science.gov (United States)

Charalampidis, C.; van As, D.; Box, J. E.; van den Broeke, M. R.; Colgan, W. T.; Doyle, S. H.; Hubbard, A. L.; MacFerrin, M.; Machguth, H.; Smeets, C. J. P. P.

2015-11-01

We present 5 years (2009-2013) of automatic weather station measurements from the lower accumulation area (1840 m a.s.l. - above sea level) of the Greenland ice sheet in the Kangerlussuaq region. Here, the summers of 2010 and 2012 were both exceptionally warm, but only 2012 resulted in a strongly negative surface mass budget (SMB) and surface meltwater run-off. The observed run-off was due to a large ice fraction in the upper 10 m of firn that prevented meltwater from percolating to available pore volume below. Analysis reveals an anomalously low 2012 summer-averaged albedo of 0.71 (typically ~ 0.78), as meltwater was present at the ice sheet surface. Consequently, during the 2012 melt season, the ice sheet surface absorbed 28 % (213 MJ m-2) more solar radiation than the average of all other years. A surface energy balance model is used to evaluate the seasonal and interannual variability of all surface energy fluxes. The model reproduces the observed melt rates as well as the SMB for each season. A sensitivity analysis reveals that 71 % of the additional solar radiation in 2012 was used for melt, corresponding to 36 % (0.64 m) of the 2012 surface lowering. The remaining 64 % (1.14 m) of surface lowering resulted from high atmospheric temperatures, up to a +2.6 °C daily average, indicating that 2012 would have been a negative SMB year at this site even without the melt-albedo feedback. Longer time series of SMB, regional temperature, and remotely sensed albedo (MODIS) show that 2012 was the first strongly negative SMB year, with the lowest albedo, at this elevation on record. The warm conditions of recent years have resulted in enhanced melt and reduction of the refreezing capacity in the lower accumulation area. If high temperatures continue, the current lower accumulation area will turn into a region with superimposed ice in coming years.

Subgrain and dislocation structure changes in hot-deformed high-temperature Fe-Ni austenitic alloy

Energy Technology Data Exchange (ETDEWEB)

Ducki, K.J.; Rodak, K.; Hetmanczyk, M.; Kuc, D

2003-08-28

The influence of plastic deformation on the substructure of a high-temperature austenitic Fe-Ni alloy has been presented. Hot-torsion tests were executed at constant strain rates of 0.1 and 1.0 s{sup -1}, at testing temperatures in the range 900-1150 deg. C. The examination of the microstructure was carried out, using transmission electron microscopy. Direct measurements on the micrographs allowed the calculation of structural parameters: the average subgrain area, and the mean dislocation density. A detailed investigation has shown that the microstructure is inhomogeneous, consisting of dense dislocation walls, subgrains and recrystallized regions.

Subgrain and dislocation structure changes in hot-deformed high-temperature Fe-Ni austenitic alloy

International Nuclear Information System (INIS)

Ducki, K.J.; Rodak, K.; Hetmanczyk, M.; Kuc, D.

2003-01-01

The influence of plastic deformation on the substructure of a high-temperature austenitic Fe-Ni alloy has been presented. Hot-torsion tests were executed at constant strain rates of 0.1 and 1.0 s -1 , at testing temperatures in the range 900-1150 deg. C. The examination of the microstructure was carried out, using transmission electron microscopy. Direct measurements on the micrographs allowed the calculation of structural parameters: the average subgrain area, and the mean dislocation density. A detailed investigation has shown that the microstructure is inhomogeneous, consisting of dense dislocation walls, subgrains and recrystallized regions

Averaging of nonlinearity-managed pulses

International Nuclear Information System (INIS)

Zharnitsky, Vadim; Pelinovsky, Dmitry

2005-01-01

We consider the nonlinear Schroedinger equation with the nonlinearity management which describes Bose-Einstein condensates under Feshbach resonance. By using an averaging theory, we derive the Hamiltonian averaged equation and compare it with other averaging methods developed for this problem. The averaged equation is used for analytical approximations of nonlinearity-managed solitons

Resource investigation of low- and moderate-temperature geothermal areas in Paso Robles, California

Energy Technology Data Exchange (ETDEWEB)

Campion, L.F.; Chapman, R.H.; Chase, G.W.; Youngs, L.G.

1983-01-01

Ninety-eight geothermal wells and springs were identified and plotted, and a geologic map and cross sections were compiled. Detailed geophysical, geochemical, and geological surveys were conducted. The geological and geophysical work delineated the basement highs and trough-like depressions that can exercise control on the occurrence of the thermal waters. The Rinconada fault was also evident. Cross sections drawn from oil well logs show the sediments conforming against these basement highs and filling the depressions. It is along the locations where the sediments meet the basement highs that three natural warm springs in the area occur. Deep circulation of meteoric waters along faults seems to be a reasonable source for the warm water. The Santa Margarita, Pancho Rico, and Paso Robles Formations would be the first permeable zones that abut the faults through which water would enter. Temperatures and interpretation of well logs indicate the warmest aquifer at the base of the Paso Robles Formation. Warm water may be entering higher up in the section, but mixing with water from cooler zones seems to be evident. Geothermometry indicates reservoir temperatures could be as high as 91/sup 0/C (196/sup 0/F).

The tunneling magnetoresistance current dependence on cross sectional area, angle and temperature

Directory of Open Access Journals (Sweden)

Z. H. Zhang

2015-03-01

Full Text Available The magnetoresistance of a MgO-based magnetic tunnel junction (MTJ was studied experimentally. The magnetoresistance as a function of current was measured systematically on MTJs for various MgO cross sectional areas and at various temperatures from 7.5 to 290.1 K. The resistance current dependence of the MTJ was also measured for different angles between the two ferromagnetic layers. By considering particle and angular momentum conservation of transport electrons, the current dependence of magnetoresistance can be explained by the changing of spin polarization in the free magnetic layer of the MTJ. The changing of spin polarization is related to the magnetoresistance, its angular dependence and the threshold current where TMR ratio equals zero. A phenomenological model is used which avoid the complicated barrier details and also describes the data.

High-average-power diode-pumped Yb: YAG lasers

International Nuclear Information System (INIS)

Avizonis, P V; Beach, R; Bibeau, C M; Emanuel, M A; Harris, D G; Honea, E C; Monroe, R S; Payne, S A; Skidmore, J A; Sutton, S B

1999-01-01

A scaleable diode end-pumping technology for high-average-power slab and rod lasers has been under development for the past several years at Lawrence Livermore National Laboratory (LLNL). This technology has particular application to high average power Yb:YAG lasers that utilize a rod configured gain element. Previously, this rod configured approach has achieved average output powers in a single 5 cm long by 2 mm diameter Yb:YAG rod of 430 W cw and 280 W q-switched. High beam quality (M(sup 2)= 2.4) q-switched operation has also been demonstrated at over 180 W of average output power. More recently, using a dual rod configuration consisting of two, 5 cm long by 2 mm diameter laser rods with birefringence compensation, we have achieved 1080 W of cw output with an M(sup 2) value of 13.5 at an optical-to-optical conversion efficiency of 27.5%. With the same dual rod laser operated in a q-switched mode, we have also demonstrated 532 W of average power with an M(sup 2) and lt; 2.5 at 17% optical-to-optical conversion efficiency. These q-switched results were obtained at a 10 kHz repetition rate and resulted in 77 nsec pulse durations. These improved levels of operational performance have been achieved as a result of technology advancements made in several areas that will be covered in this manuscript. These enhancements to our architecture include: (1) Hollow lens ducts that enable the use of advanced cavity architectures permitting birefringence compensation and the ability to run in large aperture-filling near-diffraction-limited modes. (2) Compound laser rods with flanged-nonabsorbing-endcaps fabricated by diffusion bonding. (3) Techniques for suppressing amplified spontaneous emission (ASE) and parasitics in the polished barrel rods

Temperature control system for liquid-fed ceramic melters

International Nuclear Information System (INIS)

Westsik, J.H. Jr.

1986-10-01

A temperature-feedback system has been developed for controlling electrical power to liquid-fed ceramic melters (LFCM). Software, written for a microcomputer-based data acquisition and process monitoring system, compares glass temperatures with a temperature setpoint and adjusts the electrical power accordingly. Included in the control algorithm are steps to reject failed thermocouples, spatially average the glass temperatures, smooth the averaged temperatures over time using a digital filter, and detect foaming in the glass. The temperature control system has proved effective during all phases of melter operation including startup, steady operation, loss of feed, and shutdown. This system replaces current, power, and resistance feedback control systems used previously in controlling the LFCM process

METHODS OF CONTROLLING THE AVERAGE DIAMETER OF THE THREAD WITH ASYMMETRICAL PROFILE

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L. M. Aliomarov

2015-01-01

Full Text Available To handle the threaded holes in hard materials made of marine machinery, operating at high temperatures, heavy loads and in aggressive environments, the authors have developed the combined tool core drill -tap with a special cutting scheme, which has an asymmetric thread profile on the tap part. In order to control the average diameter of the thread of tap part of the combined tool was used the method three wires, which allows to make continuous measurement of the average diameter of the thread along the entire profile. Deviation from the average diameter from the sample is registered by inductive sensor and is recorded by the recorder. In the work are developed and presented control schemes of the average diameter of the threads with a symmetrical and asymmetrical profile. On the basis of these schemes are derived formulas for calculating the theoretical option to set the wires in the thread profile in the process of measuring the average diameter. Conducted complex research and the introduction of the combined instrument core drill-tap in the production of products of marine engineering, shipbuilding, ship repair power plants made of hard materials showed a high efficiency of the proposed technology for the processing of high-quality small-diameter threaded holes that meet modern requirements.

On nonstationarity and antipersistency in global temperature series

Science.gov (United States)

KäRner, O.

2002-10-01

Statistical analysis is carried out for satellite-based global daily tropospheric and stratospheric temperature anomaly and solar irradiance data sets. Behavior of the series appears to be nonstationary with stationary daily increments. Estimating long-range dependence between the increments reveals a remarkable difference between the two temperature series. Global average tropospheric temperature anomaly behaves similarly to the solar irradiance anomaly. Their daily increments show antipersistency for scales longer than 2 months. The property points at a cumulative negative feedback in the Earth climate system governing the tropospheric variability during the last 22 years. The result emphasizes a dominating role of the solar irradiance variability in variations of the tropospheric temperature and gives no support to the theory of anthropogenic climate change. The global average stratospheric temperature anomaly proceeds like a 1-dim random walk at least up to 11 years, allowing good presentation by means of the autoregressive integrated moving average (ARIMA) models for monthly series.

Spikelet sterility in rice genotypes affected by temperature at microsporogenesis

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Natalia M. de Souza

Full Text Available ABSTRACT This study evaluated the effect of temperatures during the phase of microsporogenesis on spikelet sterility of paddy rice and identified genotypes tolerant to low temperatures at this growth stage. The inbreds SC681, SC491, and SC676 and the cultivars Epagri 109 and SCS116 Satoru were assessed. The genotypes were submitted for three days in a growth chamber to five temperatures at microsporogenesis: 9, 12, 15, 18, and 21 oC. For each tested temperature, a control was kept in the greenhouse under environmental conditions. After harvest, full and empty spikelets were counted and weighed and the percentage of spikelet sterility was determined. Data were evaluated by variance analysis using the F test. Averages were compared by Tukey’s test and regression analysis. The highest spikelet sterilities were observed when the genotypes were exposed to the temperatures of 9 and 12 oC. Genotype spikelet sterility was similar to that of the control at 21 ºC. The inbred SC 676 presented higher tolerance to lower temperatures is therefore potentially suited to generate a cultivar with adequate agronomic performance in rice growing areas prone to cold conditions at microsporogenesis.

Temperature measurement device

International Nuclear Information System (INIS)

Oltman, B.G.; Eckerman, K.F.; Romberg, G.P.; Prepejchal, W.

1975-01-01

Thermoluminescent dosimeter (TLD) material is exposed to a known amount of radiation and then exposed to the environment where temperature measurements are to be taken. After a predetermined time period, the TLD material is read in a known manner to determine the amount of radiation energy remaining in the TLD material. The difference between the energy originally stored by irradiation and that remaining after exposure to the temperature ofthe environment is a measure of the average temperature of the environment during the exposure. (U.S.)

Maximum vehicle cabin temperatures under different meteorological conditions

Science.gov (United States)

Grundstein, Andrew; Meentemeyer, Vernon; Dowd, John

2009-05-01

A variety of studies have documented the dangerously high temperatures that may occur within the passenger compartment (cabin) of cars under clear sky conditions, even at relatively low ambient air temperatures. Our study, however, is the first to examine cabin temperatures under variable weather conditions. It uses a unique maximum vehicle cabin temperature dataset in conjunction with directly comparable ambient air temperature, solar radiation, and cloud cover data collected from April through August 2007 in Athens, GA. Maximum cabin temperatures, ranging from 41-76°C, varied considerably depending on the weather conditions and the time of year. Clear days had the highest cabin temperatures, with average values of 68°C in the summer and 61°C in the spring. Cloudy days in both the spring and summer were on average approximately 10°C cooler. Our findings indicate that even on cloudy days with lower ambient air temperatures, vehicle cabin temperatures may reach deadly levels. Additionally, two predictive models of maximum daily vehicle cabin temperatures were developed using commonly available meteorological data. One model uses maximum ambient air temperature and average daily solar radiation while the other uses cloud cover percentage as a surrogate for solar radiation. From these models, two maximum vehicle cabin temperature indices were developed to assess the level of danger. The models and indices may be useful for forecasting hazardous conditions, promoting public awareness, and to estimate past cabin temperatures for use in forensic analyses.

Boundary layer structure over areas of heterogeneous heat fluxes

International Nuclear Information System (INIS)

Doran, J.C.; Barnes, F.J.; Coulter, R.L.; Crawford, T.L.

1993-01-01

In general circulation models (GCMs), some properties of a grid element are necessarily considered homogeneous. That is, for each grid volume there is associated a particular combination of boundary layer depth, vertical profiles of wind and temperature, surface fluxes of sensible and latent heat, etc. In reality, all of these quantities may exhibit significant spatial variations the grid area, and the larger the area the greater the likely variations. In balancing the benefits of higher resolution against increased computational time and expense, it is useful to consider what the consequences of such subgrid-scale variability may be. Moreover, in interpreting the results of a simulation, one must be able to define an appropriate average value over a grid. There are two aspects of this latter problem: (1) in observations, how does one take a set of discrete or volume-averaged measurements and relate these to properties of the entire domain, and (2) in computations, how can subgrid-scale features be accounted for in the model parameterizations? To address these and related issues, two field campaigns were carried out near Boardman, Oregon, in June 1991 and 1992. These campaigns were designed to measure the surface fluxes of latent and sensible heat over adjacent areas with strongly contrasting surface types and to measure the response of the boundary layer to those fluxes. This paper discusses some initial findings from those campaigns

Biological studies in the sea area surrounding the Loviisa nuclear power plant in the year 1977

International Nuclear Information System (INIS)

Ilus, Erkki

1980-03-01

Observations of rise in water temperature caused by the plant's cooling water were made in a large area of Haestholmsfjaerden. The mean temperatures during the growth period and summer months were on average of the same magnitude as those in the 1970s, except very close to the outlet, where the mean temperatures were clearly increased by the cooling water. The salinity of the water increased to exceptionally high values in September in the whole study area. Salinities even exceeding 0.6% were measured in the surface water of Haestholmsfjaerden. The concentrations of total phosphorus and total nitrogen were clearly above the level found earlier in the area, but the increase in the nutrient level was similar at all stations (including the reference station at Pernajanlahti). The amount of oxygen in the bottom water of the deep part of Haestholmsfjaerden in late summer was lower than in previous years (1.2 ml/l, 14% of the saturation level). The phytoplankton biomass spring maximum was greater at all stations than in 1974-76. Differences in species composition were small compared with earlier years. The amounts of chlorophyll a during the spring maximum were higher in 1977 than in 1975-76. The level of phytoplankton primary production in the whole study area was lower in 1977 than in the 1970s on average. The annual production at station nearest the outlet, was about 10% greater than at station situated in the middle of Haestholmsfjaerden, owing to higher production in the middle of summer. No important differences in 'in vitro' primary production were observed between sampling places near the water intake and the outlet and the values were of the same magnitude as in 1976. (T.V.)

Low-Temperature Preparation of Tungsten Oxide Anode Buffer Layer via Ultrasonic Spray Pyrolysis Method for Large-Area Organic Solar Cells

Directory of Open Access Journals (Sweden)

Ran Ji

2017-07-01

Full Text Available Tungsten oxide (WO3 is prepared by a low-temperature ultrasonic spray pyrolysis method in air atmosphere, and it is used as an anode buffer layer (ABL for organic solar cells (OSCs. The properties of the WO3 transition metal oxide material as well as the mechanism of ultrasonic spray pyrolysis processes are investigated. The results show that the ultrasonic spray pyrolysized WO3 ABL exhibits low roughness, matched energy level, and high conductivity, which results in high charge transport efficiency and suppressive recombination in OSCs. As a result, compared to the OSCs based on vacuum thermal evaporated WO3, a higher power conversion efficiency of 3.63% is reached with low-temperature ultrasonic spray pyrolysized WO3 ABL. Furthermore, the mostly spray-coated OSCs with large area was fabricated, which has a power conversion efficiency of ~1%. This work significantly enhances our understanding of the preparation and application of low temperature-processed WO3, and highlights the potential of large area, all spray coated OSCs for sustainable commercial fabrication.

Climate influences the leaf area/sapwood area ratio in Scots pine.

Science.gov (United States)

Mencuccini, M; Grace, J

1995-01-01

We tested the hypothesis that the leaf area/sapwood area ratio in Scots pine (Pinus sylvestris L.) is influenced by site differences in water vapor pressure deficit of the air (D). Two stands of the same provenance were selected, one in western Scotland and one in eastern England, so that effects resulting from age, genetic variability, density and fertility were minimized. Compared with the Scots pine trees at the cooler and wetter site in Scotland, the trees at the warmer and drier site in England produced less leaf area per unit of conducting sapwood area both at a stem height of 1.3 m and at the base of the live crown, whereas stem permeability was similar at both sites. Also, trees at the drier site had less leaf area per unit branch cross-sectional area at the branch base than trees at the wetter site. For each site, the average values for leaf area, sapwood area and permeability were used, together with values of transpiration rates at different D, to calculate average stem water potential gradients. Changes in the leaf area/sapwood area ratio acted to maintain a similar water potential gradient in the stems of trees at both sites despite climatic differences between the sites.

Effect of various solvents on the viscosity-average molecular weight of poly (vinyl acetate)

International Nuclear Information System (INIS)

Rehman, W.U.; But, M.A.; Chughtai, A.; Jamil, T.; Sattar, A.

2006-01-01

Solution polymerization of Vinyl Acetate was carried out in various solvents (benzene, toluene, ethyl acetate, acetonitrile). Dilute solution viscometry was used to determine the viscosity-average molecular weight of the resulting Poly (Vinyl Acetate) (PV Ac) in each case. The viscosity-average molecular weight (M,J of PVAc was found to increase in the order benzene < toluene < ethyl acetate < acetonitrile, It was concluded that under the same reaction conditions (polymerization time, initiator quantity, solvent/monomer ratio, temperature), acetonitrile served as the best solvent for solution. polymerization of Vinyl Acetate monomer. (author)

Fluid Phase Lipid Areas and Bilayer Thicknesses of Commonly Used Phosphatidylcholines as a Function of Temperature

International Nuclear Information System (INIS)

Kucerka, Norbert; Nieh, Mu-Ping; Katsaras, John

2011-01-01

The structural parameters of fluid phase bilayers composed of phosphatidylcholines with fully saturated, mixed, and branched fatty acid chains, at several temperatures, have been determined by simultaneously analyzing small-angle neutron and X-ray scattering data. Bilayer parameters, such as area per lipid and overall bilayer thickness have been obtained in conjunction with intrabilayer structural parameters (e.g. hydrocarbon region thickness). The results have allowed us to assess the effect of temperature and hydrocarbon chain composition on bilayer structure. For example, we found that for all lipids there is, not surprisingly, an increase in fatty acid chain trans-gauche isomerization with increasing temperature. Moreover, this increase in trans-gauche isomerization scales with fatty acid chain length in mixed chain lipids. However, in the case of lipids with saturated fatty acid chains, trans-gauche isomerization is increasingly tempered by attractive chain-chain van der Waals interactions with increasing chain length. Finally, our results confirm a strong dependence of lipid chain dynamics as a function of double bond position along fatty acid chains.

Temperature effects on hospital admissions for kidney morbidity in Taiwan

International Nuclear Information System (INIS)

Lin, Yu-Kai; Wang, Yu-Chun; Ho, Tsung-Jung; Lu, Chensheng

2013-01-01

Objective: This study aimed to associate hospital admissions of kidney diseases with extreme temperature and prolonged heat/cold events in 7 regions of Taiwan. Methods: Age-specific ( 10 , O 3 , and NO 2 ) and potential confounders. Results: We observed a V or J-shape association between daily average temperatures and the RR estimates for hospital admissions of kidney diseases in Taiwan. The lowest risk for hospital admissions of kidney diseases was found at around 25 °C, and risk increased as temperatures deviated from 25 °C. The pooled cumulative 8-day RR for all ages of population of the 7 study areas were 1.10 (95% confidence interval (CI): 1.01, 1.19) at 18 °C and 1.45 (95% CI: 1.27, 1.64) at 30 °C. High temperature has more profound influence on hospital admission of kidney diseases than low temperature. Temperature risks for hospital admissions were similar between younger (< 65 years) and elderly (65 + years) population. This study observed no significant effects of prolonged heat extremes on hospital admissions of kidney diseases. Conclusions: The heat effect for kidney morbidities leading to hospital admission was more significant than that of the cold temperature. This study did not find the age-dependent relative risks for temperature associating with hospital admissions of kidney diseases. - Highlights: ► V or J-shaped association was observed between daily temperatures and hospital admissions for renal diseases in Taiwan. ► The pooled relative risks accounting for 8 days of lag for the 7 study areas were 1.1 at 18 °C and 1.46 at 30 °C. ► There is no difference of the relative risk estimates for hospital admissions between younger and elderly population. ► We found significant protective effects of hospital admissions for prolonged cold extremes, but not for heat extremes

The difference between alternative averages

Directory of Open Access Journals (Sweden)

James Vaupel

2012-09-01

Full Text Available BACKGROUND Demographers have long been interested in how compositional change, e.g., change in age structure, affects population averages. OBJECTIVE We want to deepen understanding of how compositional change affects population averages. RESULTS The difference between two averages of a variable, calculated using alternative weighting functions, equals the covariance between the variable and the ratio of the weighting functions, divided by the average of the ratio. We compare weighted and unweighted averages and also provide examples of use of the relationship in analyses of fertility and mortality. COMMENTS Other uses of covariances in formal demography are worth exploring.

A Stochastic Model of Space-Time Variability of Tropical Rainfall: I. Statistics of Spatial Averages

Science.gov (United States)

Kundu, Prasun K.; Bell, Thomas L.; Lau, William K. M. (Technical Monitor)

2002-01-01

Global maps of rainfall are of great importance in connection with modeling of the earth s climate. Comparison between the maps of rainfall predicted by computer-generated climate models with observation provides a sensitive test for these models. To make such a comparison, one typically needs the total precipitation amount over a large area, which could be hundreds of kilometers in size over extended periods of time of order days or months. This presents a difficult problem since rain varies greatly from place to place as well as in time. Remote sensing methods using ground radar or satellites detect rain over a large area by essentially taking a series of snapshots at infrequent intervals and indirectly deriving the average rain intensity within a collection of pixels , usually several kilometers in size. They measure area average of rain at a particular instant. Rain gauges, on the other hand, record rain accumulation continuously in time but only over a very small area tens of centimeters across, say, the size of a dinner plate. They measure only a time average at a single location. In making use of either method one needs to fill in the gaps in the observation - either the gaps in the area covered or the gaps in time of observation. This involves using statistical models to obtain information about the rain that is missed from what is actually detected. This paper investigates such a statistical model and validates it with rain data collected over the tropical Western Pacific from ship borne radars during TOGA COARE (Tropical Oceans Global Atmosphere Coupled Ocean-Atmosphere Response Experiment). The model incorporates a number of commonly observed features of rain. While rain varies rapidly with location and time, the variability diminishes when averaged over larger areas or longer periods of time. Moreover, rain is patchy in nature - at any instant on the average only a certain fraction of the observed pixels contain rain. The fraction of area covered by

A Group Neighborhood Average Clock Synchronization Protocol for Wireless Sensor Networks

Science.gov (United States)

Lin, Lin; Ma, Shiwei; Ma, Maode

2014-01-01

Clock synchronization is a very important issue for the applications of wireless sensor networks. The sensors need to keep a strict clock so that users can know exactly what happens in the monitoring area at the same time. This paper proposes a novel internal distributed clock synchronization solution using group neighborhood average. Each sensor node collects the offset and skew rate of the neighbors. Group averaging of offset and skew rate value are calculated instead of conventional point-to-point averaging method. The sensor node then returns compensated value back to the neighbors. The propagation delay is considered and compensated. The analytical analysis of offset and skew compensation is presented. Simulation results validate the effectiveness of the protocol and reveal that the protocol allows sensor networks to quickly establish a consensus clock and maintain a small deviation from the consensus clock. PMID:25120163

SPATIAL AND TEMPORAL VARIATION OF LAND SURFACE TEMPERATURE IN FUJIAN PROVINCE FROM 2001 TO 2015

Directory of Open Access Journals (Sweden)

Y. Li

2018-04-01

Full Text Available Land surface temperature (LST is an essential parameter in the physics of land surface processes. The spatiotemporal variations of LST on the Fujian province were studied using AQUA Moderate Resolution Imaging Spectroradiometer LST data. Considering the data gaps in remotely sensed LST products caused by cloud contamination, the Savitzky-Golay (S-G filter method was used to eliminate the influence of cloud cover and to describe the periodical signals of LST. Observed air temperature data from 27 weather stations were employed to evaluate the fitting performance of the S-G filter method. Results indicate that S-G can effectively fit the LST time series and remove the influence of cloud cover. Based on the S-G-derived result, Spatial and temporal Variations of LST in Fujian province from 2001 to 2015 are analysed through slope analysis. The results show that: 1 the spatial distribution of annual mean LST generally exhibits consistency with altitude in the study area and the average of LST was much higher in the east than in the west. 2 The annual mean temperature of LST declines slightly among 15 years in Fujian. 3 Slope analysis reflects the spatial distribution characteristics of LST changing trend in Fujian.Improvement areas of LST are mainly concentrated in the urban areas of Fujian, especially in the eastern urban areas. Apparent descent areas are mainly distributed in the area of Zhangzhou and eastern mountain area.

Spatial and Temporal Variation of Land Surface Temperature in Fujian Province from 2001 TO 2015

Science.gov (United States)

Li, Y.; Wang, X.; Ding, Z.

2018-04-01

Land surface temperature (LST) is an essential parameter in the physics of land surface processes. The spatiotemporal variations of LST on the Fujian province were studied using AQUA Moderate Resolution Imaging Spectroradiometer LST data. Considering the data gaps in remotely sensed LST products caused by cloud contamination, the Savitzky-Golay (S-G) filter method was used to eliminate the influence of cloud cover and to describe the periodical signals of LST. Observed air temperature data from 27 weather stations were employed to evaluate the fitting performance of the S-G filter method. Results indicate that S-G can effectively fit the LST time series and remove the influence of cloud cover. Based on the S-G-derived result, Spatial and temporal Variations of LST in Fujian province from 2001 to 2015 are analysed through slope analysis. The results show that: 1) the spatial distribution of annual mean LST generally exhibits consistency with altitude in the study area and the average of LST was much higher in the east than in the west. 2) The annual mean temperature of LST declines slightly among 15 years in Fujian. 3) Slope analysis reflects the spatial distribution characteristics of LST changing trend in Fujian.Improvement areas of LST are mainly concentrated in the urban areas of Fujian, especially in the eastern urban areas. Apparent descent areas are mainly distributed in the area of Zhangzhou and eastern mountain area.

Containment test in area of high latitude and low temperature

International Nuclear Information System (INIS)

Cai Jiantao; Ni Yongsheng; Jia Wutong

2014-01-01

The effects of high latitude and low temperature on containment test are detailed analyzed from the view of design, equipment, construct and start-up, and the solution is put forward. The major problems resolved is as below: the effects of low temperature and high wind on defect inspection of the containment surface, the effects of test load on the affiliated equipment of containment in the condition of low temperature, and the effects of low temperature on the containment leak rate measurement. Application in Hongyanhe Unit 1 showed that the proposed scheme can effectively overcome the influence of adverse weather on the containment test. (authors)

Cooling systems of the resting area in free stall dairy barn

Science.gov (United States)

Calegari, F.; Calamari, L.; Frazzi, E.

2016-04-01

A study during the summer season evaluated the effect of different cooling systems on behavioral and productive responses of Italian Friesian dairy cows kept in an experimental-free stall barn located in the Po Valley in Italy. The study involved 30 lactating dairy cows subdivided into two groups kept in two pens with external hard court paddock in each free stall. The same cooling system was applied in the feeding area in both pens. A different cooling system in the resting area was applied to the two pens: in the pen SW, the resting area was equipped with fans and misters; in the other, there was simple ventilation (SV). Breathing rate, rectal temperature, milk yield, and milk characteristics (fat, protein, and somatic cell count) were measured. Behavioral activities (standing and lying cows in the different areas, as well as the animals in the feed bunk) were recorded. Mild to moderate heat waves during the trial were observed. On average, the breathing rate was numerically greater in SV compared with SW cows (60.2 and 55.8 breath/min, respectively), and mean rectal temperature remained below 39 °C in both groups during the trial (on average 38.7 and 38.8 °C in SV and SW, respectively. During the hotter periods of the trial, the time spent lying indoor in the free stall was greater in SW (11.8 h/day) than SV (10.7 h/day). Conversely, the time spent standing indoor without feeding was greater in SV (4.3 h/day) than SW (3.8 h/day). Milk yield was slightly better maintained during hotter period in SW compared with SV and somatic cell count was also slightly greater in the former. In conclusion, the adoption of the cooling system by means of evaporative cooling also in the resting area reduces the alteration of time budget caused by heat stress.

Stand-Alone Photovoltaic System Assessment in Warmer Urban Areas in Mexico

Directory of Open Access Journals (Sweden)

Alberto-Jesus Perea-Moreno

2018-01-01

Full Text Available The aim of this study is to examine the possibility of using a stand-alone photovoltaic system (SAPVS for electricity generation in urban areas in Southern Mexico. In Mexico, an urban area is defined as an area where more than 2500 inhabitants live. Due to constant migration from the countryside to the cities, the number of inhabitants of urban localities has been increasing. Global horizontal irradiation (GHI data were recorded every 10 min during 2014–2016 in Coatzacoalcos in the state of Veracruz located on 18°08′09″ N and 94°27′48″ W. In this study, batteries represented 77% of the total cost, 12 PV panels of 310 W could export 5.41 MWh to the grid, and an inverter with an integrated controller and charger was selected, which decreased the initial cost. The city of Coatzacoalcos was chosen because the average annual temperature is 28°, with an average relative humidity of 75% and an average irradiance of 5.3 kWh/m2/day. An emission factor 0.505 tCO2/MWh of greenhouse gases (GHG were obtained, based on the power system, the reduction of net annual GHG would be 11 tCO2 and a financial revenue of 36.951 × 103 $/tCO2 would be obtained. Financial parameters such as a 36.3% Internal Rate Return (IRR and 3.4 years payback show the financial viability of this investment. SAPVSs in urban areas in Mexico could be a benefit as long as housing has a high consumption of electricity.

Experimental Investigation of Temperature Distribution along the Length of Uniform Area Fin for Forced and Free Convection

Science.gov (United States)

Kannojiya, Vikas; Sharma, Riya; Gaur, Rahul; Jangra, Anil; Yadav, Pushpender; Prajapati, Pooja

2018-03-01

The overheating of an industrial component sometimes may leads to system failure. The convection heat transfer from a heated surface can be effectively enhanced by employing fins on that surface. This Paper emphasizes on the experimental investigation of temperature distribution along the length of pin shaped fin. The analysis is performed on a 100 mm long fin made up of brass with 19.6 mm diameter having thermal conductivity as 111 W/m.K. Temperature at different section of the fin along its length is evaluated experimentally and theoretically. The influence of convection mode viz natural & forced convection and variable heat input on the temperature distribution is evaluated. The result outcomes are then compared with the widely accepted analytical relations. A comparison of convective heat transfer coefficient for uniform and non-uniform area fin is also presented. The results by experimental and analytical method are found to be in good agreement for free convection phenomenon.

Extreme temperature events affecting the electricity distribution system of the metropolitan area of Buenos Aires (1971–2013)

International Nuclear Information System (INIS)

Santágata, Daniela M.; Castesana, Paula; Rössler, Cristina E.; Gómez, Darío R.

2017-01-01

We studied the role of cold waves and heat waves on major power outages in the metropolitan area of Buenos Aires. Impacts of events occurring in the tails of distributions were assessed estimating deviations of minimum temperature, maximum temperature and hourly electricity consumption with respect to statistically derived thresholds and using three sets of data: temperature observations (1911–2013); major power outages reported in a disaster database (1971–2013) and hourly electricity consumption (2006–2013). These deviations (exceedances) proved to be adequate indicators of the stress posed by extreme temperature events to the electricity distribution system leading to major blackouts. Based on these indicators, we found that the electricity distribution system was under similar stress during cold waves or heat waves, but it was much more vulnerable to heat waves (three blackouts under cold waves against 20 under heat waves between 2006 and 2013). For heat waves, the results of a binomial regression logistic model provided an adequate description of the probability of disastrous supply interruptions in terms of exceedances in extreme temperatures and electricity consumption stress. This approach may be of use for other cities wishing to evaluate the effects of extreme temperature events on the electricity distribution infrastructure. - Highlights: • The linkage between extreme temperatures and disastrous power outages is analyzed. • Exceedance in extreme temperature and electricity consumption are stress indicators. • Extreme temperatures pose moderate to extreme impacts to electricity distribution. • Electricity distribution is more vulnerable to heat waves than cold waves.

Langmuir probe measurements in a time-fluctuating-highly ionized non-equilibrium cutting arc: Analysis of the electron retarding part of the time-averaged current-voltage characteristic of the probe

Energy Technology Data Exchange (ETDEWEB)

Prevosto, L.; Mancinelli, B. [Grupo de Descargas Eléctricas, Departamento Ing. Electromecánica, Facultad Regional Venado Tuerto (UTN), Laprida 651, Venado Tuerto (2600) Santa Fe (Argentina); Kelly, H. [Grupo de Descargas Eléctricas, Departamento Ing. Electromecánica, Facultad Regional Venado Tuerto (UTN), Laprida 651, Venado Tuerto (2600) Santa Fe (Argentina); Instituto de Física del Plasma (CONICET), Departamento de Física, Facultad de Ciencias Exactas y Naturales (UBA) Ciudad Universitaria Pab. I, 1428 Buenos Aires (Argentina)

2013-12-15

This work describes the application of Langmuir probe diagnostics to the measurement of the electron temperature in a time-fluctuating-highly ionized, non-equilibrium cutting arc. The electron retarding part of the time-averaged current-voltage characteristic of the probe was analysed, assuming that the standard exponential expression describing the electron current to the probe in collision-free plasmas can be applied under the investigated conditions. A procedure is described which allows the determination of the errors introduced in time-averaged probe data due to small-amplitude plasma fluctuations. It was found that the experimental points can be gathered into two well defined groups allowing defining two quite different averaged electron temperature values. In the low-current region the averaged characteristic was not significantly disturbed by the fluctuations and can reliably be used to obtain the actual value of the averaged electron temperature. In particular, an averaged electron temperature of 0.98 ± 0.07 eV (= 11400 ± 800 K) was found for the central core of the arc (30 A) at 3.5 mm downstream from the nozzle exit. This average included not only a time-average over the time fluctuations but also a spatial-average along the probe collecting length. The fitting of the high-current region of the characteristic using such electron temperature value together with the corrections given by the fluctuation analysis showed a relevant departure of local thermal equilibrium in the arc core.

Langmuir probe measurements in a time-fluctuating-highly ionized non-equilibrium cutting arc: Analysis of the electron retarding part of the time-averaged current-voltage characteristic of the probe

International Nuclear Information System (INIS)

Prevosto, L.; Mancinelli, B.; Kelly, H.

2013-01-01

This work describes the application of Langmuir probe diagnostics to the measurement of the electron temperature in a time-fluctuating-highly ionized, non-equilibrium cutting arc. The electron retarding part of the time-averaged current-voltage characteristic of the probe was analysed, assuming that the standard exponential expression describing the electron current to the probe in collision-free plasmas can be applied under the investigated conditions. A procedure is described which allows the determination of the errors introduced in time-averaged probe data due to small-amplitude plasma fluctuations. It was found that the experimental points can be gathered into two well defined groups allowing defining two quite different averaged electron temperature values. In the low-current region the averaged characteristic was not significantly disturbed by the fluctuations and can reliably be used to obtain the actual value of the averaged electron temperature. In particular, an averaged electron temperature of 0.98 ± 0.07 eV (= 11400 ± 800 K) was found for the central core of the arc (30 A) at 3.5 mm downstream from the nozzle exit. This average included not only a time-average over the time fluctuations but also a spatial-average along the probe collecting length. The fitting of the high-current region of the characteristic using such electron temperature value together with the corrections given by the fluctuation analysis showed a relevant departure of local thermal equilibrium in the arc core

Langmuir probe measurements in a time-fluctuating-highly ionized non-equilibrium cutting arc: analysis of the electron retarding part of the time-averaged current-voltage characteristic of the probe.

Science.gov (United States)

Prevosto, L; Kelly, H; Mancinelli, B

2013-12-01

This work describes the application of Langmuir probe diagnostics to the measurement of the electron temperature in a time-fluctuating-highly ionized, non-equilibrium cutting arc. The electron retarding part of the time-averaged current-voltage characteristic of the probe was analysed, assuming that the standard exponential expression describing the electron current to the probe in collision-free plasmas can be applied under the investigated conditions. A procedure is described which allows the determination of the errors introduced in time-averaged probe data due to small-amplitude plasma fluctuations. It was found that the experimental points can be gathered into two well defined groups allowing defining two quite different averaged electron temperature values. In the low-current region the averaged characteristic was not significantly disturbed by the fluctuations and can reliably be used to obtain the actual value of the averaged electron temperature. In particular, an averaged electron temperature of 0.98 ± 0.07 eV (= 11400 ± 800 K) was found for the central core of the arc (30 A) at 3.5 mm downstream from the nozzle exit. This average included not only a time-average over the time fluctuations but also a spatial-average along the probe collecting length. The fitting of the high-current region of the characteristic using such electron temperature value together with the corrections given by the fluctuation analysis showed a relevant departure of local thermal equilibrium in the arc core.

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Dome Reef, 1989 - 2003 (NODC Accession 0002809)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Dome Reef, 2006 - 2007 (NODC Accession 0029107)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Dome Reef, 2005 - 2006 (NODC Accession 0014268)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Alligator Reef, 2005 - 2007 (NODC Accession 0019351)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Grecian Rocks, 2005 - 2007 (NODC Accession 0039973)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Track at Tennessee Reef, 1990 - 2004 (NODC Accession 0002749)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Triumph Reef, 1990 - 2006 (NODC accession 0013166)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Grecian Rocks, 1990 - 2005 (NODC Accession 0011143)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Cape Florida, 2005 - 2006 (NODC Accession 0014185)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Looe Iselin, 2006 - 2007 (NODC Accession 0039240)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Bullard Bank, 1992 - 2005 (NODC Accession 0010426)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Cape Florida, 1996 - 2005 (NODC Accession 0002788)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Sprigger Bank, 1992 - 2006 (NODC accession 0013114)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Looe Iselin, 2004-2006 (NODC Accession 0014271)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Long Key, 2008 - 2010 (NODC Accession 0093063)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Smith Shoal, 1998 - 2006 (NODC Accession 0014121)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Looe Buoy, 1988 - 2004 (NODC Accession 0002616)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Bullard Bank, 2005 - 2007 (NODC Accession 0039881)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Triumph Reef, 1990 - 2006 (NODC Accession 0013166)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Carysfort Reef, 2006-2010 (NODC Accession 0093022)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Grecian Rocks, 2007 - 2010 (NODC Accession 0093026)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Alligator Reef, 2007-2010 (NODC Accession 0093017)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Tennessee Reef, 2004-2006 (NODC Accession 0014272)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Long Key, 2005-2006 (NODC Accession 0014269)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Late Pleistocene temperature history of Southeast Africa: A TEX(86) temperature record from Lake Malawi

NARCIS (Netherlands)

Woltering, M.; Johnson, T.C.; Werne, J.P.; Schouten, S.; Sinninghe Damsté, J.S.

2011-01-01

We present a TEX86-derived surface water temperaturerecord for LakeMalawi that provides the first continuous continental record of temperature variability in the continental tropics spanning the past ∼ 74 kyr with millennial-scale resolution. Average temperature during Marine Isotope Stage (MIS) 5A

Low temperature industrial waste heat utilization in the area 'Speyer-Ludwigshafen-Frankenthal-Worms'

International Nuclear Information System (INIS)

Nunold, K.; Krebs, A.

1982-01-01

The aim of the study is the elaboration of reliable facts whether and under which conditions low temperature industrial waste heat systems can be economically utilized for heating purposes. The source of the waste heat are power- and industrial plants. In order to obtain reliable results, investigations have been carried out in the area Speyer-Ludwigshafen-Frankenthal and Worms. These investigations showed a number of application possibilities for heat pumps and it became moreover evident that there is a high variaiton of the heat requirement due to social components and the different type of building structures of the consumers. The economic results showed that the application of this heating system can under certain conditions supplement resp. replace other heating systems. (orig.) [de

Non-invasive body temperature measurement of wild chimpanzees using fecal temperature decline.

Science.gov (United States)

Jensen, Siv Aina; Mundry, Roger; Nunn, Charles L; Boesch, Christophe; Leendertz, Fabian H

2009-04-01

New methods are required to increase our understanding of pathologic processes in wild mammals. We developed a noninvasive field method to estimate the body temperature of wild living chimpanzees habituated to humans, based on statistically fitting temperature decline of feces after defecation. The method was established with the use of control measures of human rectal temperature and subsequent changes in fecal temperature over time. The method was then applied to temperature data collected from wild chimpanzee feces. In humans, we found good correspondence between the temperature estimated by the method and the actual rectal temperature that was measured (maximum deviation 0.22 C). The method was successfully applied and the average estimated temperature of the chimpanzees was 37.2 C. This simple-to-use field method reliably estimates the body temperature of wild chimpanzees and probably also other large mammals.

A Group Neighborhood Average Clock Synchronization Protocol for Wireless Sensor Networks

Directory of Open Access Journals (Sweden)

Lin Lin

2014-08-01

Full Text Available Clock synchronization is a very important issue for the applications of wireless sensor networks. The sensors need to keep a strict clock so that users can know exactly what happens in the monitoring area at the same time. This paper proposes a novel internal distributed clock synchronization solution using group neighborhood average. Each sensor node collects the offset and skew rate of the neighbors. Group averaging of offset and skew rate value are calculated instead of conventional point-to-point averaging method. The sensor node then returns compensated value back to the neighbors. The propagation delay is considered and compensated. The analytical analysis of offset and skew compensation is presented. Simulation results validate the effectiveness of the protocol and reveal that the protocol allows sensor networks to quickly establish a consensus clock and maintain a small deviation from the consensus clock.

Dynamic Model Averaging in Large Model Spaces Using Dynamic Occam's Window.

Science.gov (United States)

Onorante, Luca; Raftery, Adrian E

2016-01-01

Bayesian model averaging has become a widely used approach to accounting for uncertainty about the structural form of the model generating the data. When data arrive sequentially and the generating model can change over time, Dynamic Model Averaging (DMA) extends model averaging to deal with this situation. Often in macroeconomics, however, many candidate explanatory variables are available and the number of possible models becomes too large for DMA to be applied in its original form. We propose a new method for this situation which allows us to perform DMA without considering the whole model space, but using a subset of models and dynamically optimizing the choice of models at each point in time. This yields a dynamic form of Occam's window. We evaluate the method in the context of the problem of nowcasting GDP in the Euro area. We find that its forecasting performance compares well with that of other methods.

Bayesian model averaging and weighted average least squares : Equivariance, stability, and numerical issues

NARCIS (Netherlands)

De Luca, G.; Magnus, J.R.

2011-01-01

In this article, we describe the estimation of linear regression models with uncertainty about the choice of the explanatory variables. We introduce the Stata commands bma and wals, which implement, respectively, the exact Bayesian model-averaging estimator and the weighted-average least-squares

Study of critical free-area ratio during the snow-melting process on pavement using low-temperature heating fluids

Energy Technology Data Exchange (ETDEWEB)

Wang, Huajun [School of Energy and Environment Engineering, Hebei University of Technology, Tianjin 300401 (China); Chen, Zhihao [Faculty of Engineering, Yokohama National University, Hodogaya, Yokohama 240-8501 (Japan)

2009-01-15

Critical free-area ratio (CFR) is an interesting phenomenon during the snow-melting process on pavement using low-temperature heating fluids such as geothermal tail water and industrial waste water. This paper is performed to further investigate the mechanism of CFR and its influencing factors. A simplified theoretical model is presented to describe the heat and mass transfer process on pavement. Especially the variation of thermal properties and the capillary effect of snow layer are considered. Numerical computation shows that the above theoretical model is effective for the prediction of CFR during the snow-melting process. Furthermore, the mechanism of CFR is clarified in detail. CFR is independent of the layout of hydronic pipes, the fluid temperature, the idling time, and weather conditions. It is both the non-uniform temperature distribution and complicated porous structure of snow layer that lead to the occurrence of CFR. Besides, the influences of operation parameters including the fluid temperature, the idling time, the pipe spacing and buried depths on snow melting are analyzed, which are helpful for the next optimal design of snow-melting system. (author)

Study of critical free-area ratio during the snow-melting process on pavement using low-temperature heating fluids

Energy Technology Data Exchange (ETDEWEB)

Wang Huajun [School of Energy and Environment Engineering, Hebei University of Technology, Tianjin 300401 (China)], E-mail: huajunwang@126.com; Chen Zhihao [Faculty of Engineering, Yokohama National University, Hodogaya, Yokohama 240-8501 (Japan)

2009-01-15

Critical free-area ratio (CFR) is an interesting phenomenon during the snow-melting process on pavement using low-temperature heating fluids such as geothermal tail water and industrial waste water. This paper is performed to further investigate the mechanism of CFR and its influencing factors. A simplified theoretical model is presented to describe the heat and mass transfer process on pavement. Especially the variation of thermal properties and the capillary effect of snow layer are considered. Numerical computation shows that the above theoretical model is effective for the prediction of CFR during the snow-melting process. Furthermore, the mechanism of CFR is clarified in detail. CFR is independent of the layout of hydronic pipes, the fluid temperature, the idling time, and weather conditions. It is both the non-uniform temperature distribution and complicated porous structure of snow layer that lead to the occurrence of CFR. Besides, the influences of operation parameters including the fluid temperature, the idling time, the pipe spacing and buried depths on snow melting are analyzed, which are helpful for the next optimal design of snow-melting system.

Study of critical free-area ratio during the snow-melting process on pavement using low-temperature heating fluids

International Nuclear Information System (INIS)

Wang Huajun; Chen Zhihao

2009-01-01

Critical free-area ratio (CFR) is an interesting phenomenon during the snow-melting process on pavement using low-temperature heating fluids such as geothermal tail water and industrial waste water. This paper is performed to further investigate the mechanism of CFR and its influencing factors. A simplified theoretical model is presented to describe the heat and mass transfer process on pavement. Especially the variation of thermal properties and the capillary effect of snow layer are considered. Numerical computation shows that the above theoretical model is effective for the prediction of CFR during the snow-melting process. Furthermore, the mechanism of CFR is clarified in detail. CFR is independent of the layout of hydronic pipes, the fluid temperature, the idling time, and weather conditions. It is both the non-uniform temperature distribution and complicated porous structure of snow layer that lead to the occurrence of CFR. Besides, the influences of operation parameters including the fluid temperature, the idling time, the pipe spacing and buried depths on snow melting are analyzed, which are helpful for the next optimal design of snow-melting system

Doses to early entrants to the A-bombed areas and to residents of the fallout areas and 137Cs in soil of the 'black rain' area in Hiroshima

International Nuclear Information System (INIS)

Takeshita, Kenji

1976-01-01

An external exposure dose from residual activity (induced radioactivity in the fallout areas and radioactive fallout in the ''black rain'' area) caused by an atomic bomb in Hiroshima was estimated. The integrated doses to the infinite time averaged 101 rads in the atomic bombed area of Hiroshima and 32 rads in that area of Nagasaki. According to the measurement by investigators, the integrated doses of the external exposure dose due to radioactive fallout averaged 13 rads. The amount of 137 Cs in soils was determined in the southest slanting surface

Habitat Characteristics of Bracken-Covered Areas Intended for Afforestation in Ličko Sredogorje

Directory of Open Access Journals (Sweden)

Zvonko Seletković

2013-12-01

Full Text Available Background and Purpose: Forest cultures in continental part of Croatia are mainly based on bracken-covered areas and moors on deserted agriculture soils and pastures. Successful afforestation i.e. establishment of forest cultures depends among other things on the understanding of habitats and ecology of forest trees. The choice of best species of forest trees for afforestation needs to be based on the research in soil and climate characteristics of target habitats. The aims of this research were to show mesoclimatic characteristics of Ličko sredogorje and microclimatic and pedological characteristics of Ličko polje. Also, based on habitat characteristics and ecology of forest trees, the aim was to determine species of forest trees suitable for afforestation of bracken-covered areas. Materials and Methods: Climate, microclimate, pedological and plant nutrition researches were done at the area of Lika highlands. Climate analysis was done according to air temperatures, amount of precipitation, relative air humidity and other climate elements and appearances. Composite soil samples were taken from the depth of 0-30 cm in order to determine plant nutrition potential. Samples were prepared for further analysis in the laboratory. Results: The highest average annual air temperature of 9.6 °C was found at weather station Gračac and the lowest at Korenica station (8.1 °C. Average amount of precipitation for this region was around 1500 mm. Monthly rain factors were ranging from arid to perhumid. Considering thermal character of the climate, the area has moderately warm climate. Average volumetric soil humidity is 14.2 %. Soil has strong acid reaction, is very humus, good to richly supplied with total nitrogen, content of physiologically active phosphorus and potassium is low, and C/N ration normal. Conclusions: According to habitat characteristics in the area of Ličko sredogorje and ecological demands of forest tree species, forest cultures of Common

Lit and unlit side temperatures of the Main Rings of Saturn.

Science.gov (United States)

Flandes, A.; Garcia, A.; Deau, E.; Spilker, L. J.

2017-12-01

The differences in the temperatures of both the lit and unlit sides of the main rings of Saturn can reveal important information about their structure. In general, the temperature of the main rings strongly depends upon the distribution and the general structure of the ensembles of particles that compose them, mainly due to shadowing effects that modulate how much energy reaches the individual particles -granted that the direct solar energy is the main driver of the rings' temperature-. In order to reproduce the temperatures of both sides of the rings, we use a semi-analytical energy balance model (considering solar direct and Saturn reflected energy, Saturn thermal energy and particles' thermal energies), where the shadowed fractional areas of the rings are removed through a shadowing function. We obtain this function (dependent on the solar elevation angle) for 13 different regions (for the A, CD, B and C rings) along the radial direction that are simulated using arrays of lambertian spherical particles based on the average properties of the structure of these regions derived from the Cassini UVIS observations. The obtained synthetic temperatures are compared to the Cassini CIRS measured temperatures (from -22º to equinox) with good agreement.

Enhancing the Accuracy of Advanced High Temperature Mechanical Testing through Thermography

Directory of Open Access Journals (Sweden)

Jonathan Jones

2018-03-01

Full Text Available This paper describes the advantages and enhanced accuracy thermography provides to high temperature mechanical testing. This technique is not only used to monitor, but also to control test specimen temperatures where the infra-red technique enables accurate non-invasive control of rapid thermal cycling for non-metallic materials. Isothermal and dynamic waveforms are employed over a 200–800 °C temperature range to pre-oxidised and coated specimens to assess the capability of the technique. This application shows thermography to be accurate to within ±2 °C of thermocouples, a standardised measurement technique. This work demonstrates the superior visibility of test temperatures previously unobtainable by conventional thermocouples or even more modern pyrometers that thermography can deliver. As a result, the speed and accuracy of thermal profiling, thermal gradient measurements and cold/hot spot identification using the technique has increased significantly to the point where temperature can now be controlled by averaging over a specified area. The increased visibility of specimen temperatures has revealed additional unknown effects such as thermocouple shadowing, preferential crack tip heating within an induction coil, and, fundamental response time of individual measurement techniques which are investigated further.

Dynamics of Rn transport from the cellar to the living area in an unheated house

International Nuclear Information System (INIS)

Furrer, D.; Crameri, R.; Burkart, W.

1991-01-01

Environmental parameters such as temperature and wind, occupant activities, and house-specific parameters such as subsoil geology, leakiness of the substructure to soil gas, and air exchange rate are the main factors influencing Rn entry into a building and its subsequent indoor behavior. Experiments performed in an unheated, uninhabited house showed a reproducible diurnal fluctuation of the indoor concentration of Rn decay products. Strong, long-term correlations between temperature differences indoor-outdoor (indoor temperature minus outdoor temperature) and pressure differences outdoor-indoor (outdoor pressure minus indoor pressure) were found. At positive temperature differences inside-outside, an average airflow velocity of about 0.05 m s-1 between ground floor and first floor was detected. This air movement was able to vertically transport Rn at a rate of approximately 11 kBq h-1 in a volume of air of about 5.5 m3 through a cross-sectional area of only 0.03 m2. For this specific house, stack effects were identified as the main driving force for Rn migration from the cellular to higher floors. The diurnal fluctuation of Rn progeny concentrations in the living area can be explained by temporal variations in the amount of Rn-rich air transported vertically from the cellar into the building as a consequence of stack effects

RAINWATER MANAGEMENT IN PROTECTED AREAS

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Wioletta Żarnowiec

2017-03-01

Full Text Available The aim of the study was to find out whether the climate of the southern Poland allows for removing rainwater from industrial areas by evaporation from roof surfaces. The study covered the premises of a Logistics Centre with an approximate area of 34 hectares, located in the catchment of the Wedonka stream and in the region of water intake for Kraków at the Rudawa river. In the future, the Centre will comprise nine large warehouses. Road traffic associated with the project will cause potential risks for groundwater and surface water of this protected area. Therefore, the Centre’s investor decided to evaporate rainwater from the premises. To establish advisability of this plan, the study team designed and built a unique experimental station consisting of experimental roof, tank for collecting water for the sprinkler system, system for delivering, distributing and discharging water from the roof, measuring tilt tray, automatic meteorological station, and electronic devices for recording measurement data. The research on the experimental station was carried out from April to October in 2011 and 2012 and included continuous measurements of the volume of water supplied to and discharged from the roof. Moreover, the temperature of the roof and water in the tank and a number of important meteorological parameters were measured. The difference between supplied and discharged water, divided by the wetted surface of the roof, helped to determine thickness of the evaporation layer in millimeters. The study confirmed the possibility of removing potentially contaminated rainwater by evaporating it from roof surfaces of the Logistics Centre located near Kraków at an average rate of 5.9 dm3·m–2.d–1. However, due to high seasonal variability of rainfall and air temperature, it is necessary to temporarily collect water in an expansion tank of suitable capacity.

Effects of Environmental Temperature on Capnodis tenebrionis Adult Phenology

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Carmelo Peter Bonsignore

2012-01-01

Full Text Available The phenology of Capnodis tenebrionis adults was presented with reference to two different climate conditions. In a temperate moderate-warm climate, adult density showed two separate peaks during the year: one in early summer of the overwintering generation and one with beetles emerging in the late summer. In a warmer semiarid climate, the overwintering adults and the new generation overlapped during summer with a continuous increase of adult density. The difference in the average annual temperature between areas during the study period was almost 3∘C, and, in the warmer area, the new generation of C. tenebrionis emerged at least one month earlier. To make a prediction of adult presence, a model utilizing degree-days was developed from data collected over a five-year period. Models obtained from equations (Logistic 4-parameter, y(x=yo+a/(1+(x/xob of each year were developed to describe the relationship between degree-day accumulation (with a minimal threshold activity temperature of 14.21∘C calculated in the laboratory and the cumulative percentage of adult presence. According to the overall model, the 50% of overwintering beetles occurred at 726 degree-days (Biofix: 1st March and the emerging beetles occurred at 801 degree-days (Biofix: 1st July. The results show that a change in temperature is an important aspect that highlights the adaptability of this species.

The influence of green areas and roof albedos on air temperatures during extreme heat events in Berlin, Germany

Energy Technology Data Exchange (ETDEWEB)

Schubert, Sebastian; Grossmann-Clarke, Susanne [Potsdam Institute for Climate Impact Research, Potsdam (Germany)

2013-04-15

The mesoscale atmospheric model COSMO-CLM (CCLM) with the Double Canyon Effect Parametrization Scheme (DCEP) is applied to investigate possible adaption measures to extreme heat events (EHEs) for the city of Berlin, Germany. The emphasis is on the effects of a modified urban vegetation cover and roof albedo on near-surface air temperatures. Five EHEs with a duration of 5 days or more are identified for the period 2000 to 2009. A reference simulation is carried out for each EHE with current vegetation cover, roof albedo and urban canopy parameters (UCPs), and is evaluated with temperature observations from weather stations in Berlin and its surroundings. The derivation of the UCPs from an impervious surface map and a 3-D building data set is detailed. Characteristics of the simulated urban heat island for each EHE are analysed in terms of these UCPs. In addition, six sensitivity runs are examined with a modified vegetation cover of each urban grid cell by -25%, 5% and 15%, with a roof albedo increased to 0.40 and 0.65, and with a combination of the largest vegetation cover and roof albedo, respectively. At the weather stations' grid cells, the results show a maximum of the average diurnal change in air temperature during each EHE of 0.82 K and -0.48 K for the -25% and 15% vegetation covers, -0.50 K for the roof albedos of 0.65, and -0.63 K for the combined vegetation and albedo case. The largest effects on the air temperature are detected during midday. (orig.)

Radiative cooling to deep sub-freezing temperatures through a 24-h day-night cycle

Science.gov (United States)

Chen, Zhen; Zhu, Linxiao; Raman, Aaswath; Fan, Shanhui

2016-12-01

Radiative cooling technology utilizes the atmospheric transparency window (8-13 μm) to passively dissipate heat from Earth into outer space (3 K). This technology has attracted broad interests from both fundamental sciences and real world applications, ranging from passive building cooling, renewable energy harvesting and passive refrigeration in arid regions. However, the temperature reduction experimentally demonstrated, thus far, has been relatively modest. Here we theoretically show that ultra-large temperature reduction for as much as 60 °C from ambient is achievable by using a selective thermal emitter and by eliminating parasitic thermal load, and experimentally demonstrate a temperature reduction that far exceeds previous works. In a populous area at sea level, we have achieved an average temperature reduction of 37 °C from the ambient air temperature through a 24-h day-night cycle, with a maximal reduction of 42 °C that occurs when the experimental set-up enclosing the emitter is exposed to peak solar irradiance.

Radiative cooling to deep sub-freezing temperatures through a 24-h day-night cycle.

Science.gov (United States)

Chen, Zhen; Zhu, Linxiao; Raman, Aaswath; Fan, Shanhui

2016-12-13

Radiative cooling technology utilizes the atmospheric transparency window (8-13 μm) to passively dissipate heat from Earth into outer space (3 K). This technology has attracted broad interests from both fundamental sciences and real world applications, ranging from passive building cooling, renewable energy harvesting and passive refrigeration in arid regions. However, the temperature reduction experimentally demonstrated, thus far, has been relatively modest. Here we theoretically show that ultra-large temperature reduction for as much as 60 °C from ambient is achievable by using a selective thermal emitter and by eliminating parasitic thermal load, and experimentally demonstrate a temperature reduction that far exceeds previous works. In a populous area at sea level, we have achieved an average temperature reduction of 37 °C from the ambient air temperature through a 24-h day-night cycle, with a maximal reduction of 42 °C that occurs when the experimental set-up enclosing the emitter is exposed to peak solar irradiance.

Forecast of Frost Days Based on Monthly Temperatures

Science.gov (United States)

Castellanos, M. T.; Tarquis, A. M.; Morató, M. C.; Saa-Requejo, A.

2009-04-01

Although frost can cause considerable crop damage and mitigation practices against forecasted frost exist, frost forecasting technologies have not changed for many years. The paper reports a new method to forecast the monthly number of frost days (FD) for several meteorological stations at Community of Madrid (Spain) based on successive application of two models. The first one is a stochastic model, autoregressive integrated moving average (ARIMA), that forecasts monthly minimum absolute temperature (tmin) and monthly average of minimum temperature (tminav) following Box-Jenkins methodology. The second model relates these monthly temperatures to minimum daily temperature distribution during one month. Three ARIMA models were identified for the time series analyzed with a stational period correspondent to one year. They present the same stational behavior (moving average differenced model) and different non-stational part: autoregressive model (Model 1), moving average differenced model (Model 2) and autoregressive and moving average model (Model 3). At the same time, the results point out that minimum daily temperature (tdmin), for the meteorological stations studied, followed a normal distribution each month with a very similar standard deviation through years. This standard deviation obtained for each station and each month could be used as a risk index for cold months. The application of Model 1 to predict minimum monthly temperatures showed the best FD forecast. This procedure provides a tool for crop managers and crop insurance companies to asses the risk of frost frequency and intensity, so that they can take steps to mitigate against frost damage and estimated the damage that frost would cost. This research was supported by Comunidad de Madrid Research Project 076/92. The cooperation of the Spanish National Meteorological Institute and the Spanish Ministerio de Agricultura, Pesca y Alimentation (MAPA) is gratefully acknowledged.

Air temperature, radiation budget and area changes of Quisoquipina glacier in the Cordillera Vilcanota (Peru)

Science.gov (United States)

Suarez, Wilson; Macedo, Nicolás; Montoya, Nilton; Arias, Sandro; Schauwecker, Simone; Huggel, Christian; Rohrer, Mario; Condom, Thomas

2015-04-01

The Peruvian Andes host about 71% of all tropical glaciers. Although several studies have focused on glaciers of the largest glaciered mountain range (Cordillera Blanca), other regions have received little attention to date. In 2011, a new program has been initiated with the aim of monitoring glaciers in the centre and south of Peru. The monitoring program is managed by the Servicio Nacional de Meteorología e Hidrología del Perú (SENAMHI) and it is a joint project together with the Universidad San Antonio Abad de Cusco (UNSAAC) and the Autoridad Nacional del Agua (ANA). In Southern Peru, the Quisoquipina glacier has been selected due to its representativeness for glaciers in the Cordillera Vilcanota considering area, length and orientation. The Cordillera Vilcanota is the second largest mountain range in Peru with a glaciated area of approximately 279 km2 in 2009. Melt water from glaciers in this region is partly used for hydropower in the dry season and for animal breeding during the entire year. Using Landsat 5 images, we could estimate that the area of Quisoquipina glacier has decreased by approximately 11% from 3.66 km2 in 1990 to 3.26 km2 in 2010. This strong decrease is comparable to observations of other tropical glaciers. In 2011, a meteorological station has been installed on the glacier at 5180 m asl., measuring air temperature, wind speed, relative humidity, net short and longwave radiation and atmospheric pressure. Here, we present a first analysis of air temperature and the radiation budget at the Quisoquipina glacier for the first three years of measurements. Additionally, we compare the results from Quisoquipina glacier to results obtained by the Institut de recherche pour le développement (IRD) for Zongo glacier (Bolivia) and Antizana glacier (Ecuador). For both, Quisoquipina and Zongo glacier, net shortwave radiation may be the most important energy source, thus indicating the important role of albedo in the energy balance of the glacier

Temperature optimum of algae living in the outfall of a power plant on Lake Monona

International Nuclear Information System (INIS)

Brock, T.D.; Hoffmann, J.

1974-01-01

Temperature optima for photosynthesis were measured for algal populations living in the outfall of a fossil-fuel electric power plant on Lake Monona and were compared with the temperature optima of algae living in a control area in the nearby Yahara River. The temperature of the power plant outfall averaged about 8 0 C higher than that of the Yahara River. In the winter, no differences in species composition between the two study areas could be detected, Cladophora and Ulothrix being the dominant algae. The temperature optima of the populations from the two locations were the same, around 27 0 C, although the habitat temperatures at both locations were considerably lower. The only difference in response to temperature seen between the two populations was that the population at the outfall was able to photosynthesize at higher temperature, still showing high photosynthesis at 35 0 C and detectable photosynthesis at 46 0 C, a temperature at which the population from the Yahara River showed no detectable photosynthesis. In the summer, the dominant algae at the power plant outfall were Stigeoclonium and filamentous blue-green algae (family Oscillatoriaceae), whereas at the Yahara River the algal population was almost exclusively Cladophora. The temperature optima of both summer populations were the same, 31.5 0 C, only slightly higher than the mid-winter optima. Again, the population from the power plant was able to photosynthesize at higher temperature than the control population, showing quite active photosynthesis at 42.5 0 C, a temperature at which the population from the Yahara River was completely inactive. (U.S.)

Indonesia sea surface temperature from TRMM Microwave Imaging (TMI) sensor

Science.gov (United States)

Marini, Y.; Setiawan, K. T.

2018-05-01

We analysis the Tropical Rainfall Measuring Mission's (TRMM) Microwave Imager (TMI) data to monitor the sea surface temperature (SST) of Indonesia waters for a decade of 2005-2014. The TMI SST data shows the seasonal and interannual SST in Indonesian waters. In general, the SST average was highest in March-May period with SST average was 29.4°C, and the lowest was in June – August period with the SST average was 28.5°C. The monthly SST average fluctuation of Indonesian waters for 10 years tends to increase. The lowest SST average of Indonesia occurred in August 2006 with the SST average was 27.6° C, while the maximum occurred in May 2014 with the monthly SST average temperature was 29.9 ° C.

Potential for efficient frequency conversion at high average power using solid state nonlinear optical materials

International Nuclear Information System (INIS)

Eimerl, D.

1985-01-01

High-average-power frequency conversion using solid state nonlinear materials is discussed. Recent laboratory experience and new developments in design concepts show that current technology, a few tens of watts, may be extended by several orders of magnitude. For example, using KD*P, efficient doubling (>70%) of Nd:YAG at average powers approaching 100 KW is possible; and for doubling to the blue or ultraviolet regions, the average power may approach 1 MW. Configurations using segmented apertures permit essentially unlimited scaling of average power. High average power is achieved by configuring the nonlinear material as a set of thin plates with a large ratio of surface area to volume and by cooling the exposed surfaces with a flowing gas. The design and material fabrication of such a harmonic generator are well within current technology

Averaging in spherically symmetric cosmology

International Nuclear Information System (INIS)

Coley, A. A.; Pelavas, N.

2007-01-01

The averaging problem in cosmology is of fundamental importance. When applied to study cosmological evolution, the theory of macroscopic gravity (MG) can be regarded as a long-distance modification of general relativity. In the MG approach to the averaging problem in cosmology, the Einstein field equations on cosmological scales are modified by appropriate gravitational correlation terms. We study the averaging problem within the class of spherically symmetric cosmological models. That is, we shall take the microscopic equations and effect the averaging procedure to determine the precise form of the correlation tensor in this case. In particular, by working in volume-preserving coordinates, we calculate the form of the correlation tensor under some reasonable assumptions on the form for the inhomogeneous gravitational field and matter distribution. We find that the correlation tensor in a Friedmann-Lemaitre-Robertson-Walker (FLRW) background must be of the form of a spatial curvature. Inhomogeneities and spatial averaging, through this spatial curvature correction term, can have a very significant dynamical effect on the dynamics of the Universe and cosmological observations; in particular, we discuss whether spatial averaging might lead to a more conservative explanation of the observed acceleration of the Universe (without the introduction of exotic dark matter fields). We also find that the correlation tensor for a non-FLRW background can be interpreted as the sum of a spatial curvature and an anisotropic fluid. This may lead to interesting effects of averaging on astrophysical scales. We also discuss the results of averaging an inhomogeneous Lemaitre-Tolman-Bondi solution as well as calculations of linear perturbations (that is, the backreaction) in an FLRW background, which support the main conclusions of the analysis

Rock outcrops reduce temperature-induced stress for tropical conifer by decoupling regional climate in the semiarid environment.

Science.gov (United States)

Locosselli, Giuliano Maselli; Cardim, Ricardo Henrique; Ceccantini, Gregório

2016-05-01

We aimed to understand the effect of rock outcrops on the growth of Podocarpus lambertii within a microrefuge. Our hypothesis holds that the growth and survival of this species depend on the regional climate decoupling provided by rock outcrops. To test this hypothesis, we characterized the microclimate of (1) surrounding vegetation, (2) rock outcrop corridors, and (3) adjacencies. We assessed population structure by collecting data of specimen stem diameter and height. We also assessed differences between vegetation associated or not with outcrops using satellite imaging. For dendrochronological analyses, we sampled 42 individuals. Tree rings of 31 individuals were dated, and climate-growth relationships were tested. Rock outcrops produce a favorable microclimate by reducing average temperature by 4.9 °C and increasing average air humidity by 12 %. They also reduce the variability of atmospheric temperature by 42 % and air humidity by 20 % supporting a vegetation with higher leaf area index. Within this vegetation, specimen height was strongly constrained by the outcrop height. Although temperature and precipitation modulate this species growth, temperature-induced stress is the key limiting growth factor for this population of P. lambertii. We conclude that this species growth and survival depend on the presence of rock outcrops. These topography elements decouple regional climate in a favorable way for this species growth. However, these benefits are restricted to the areas sheltered by rock outcrops. Although this microrefuge supported P. lambertii growth so far, it is unclear whether this protection would be sufficient to withstand the stress of future climate changes.

Mass balance, meteorology, area altitude distribution, glacier-surface altitude, ice motion, terminus position, and runoff at Gulkana Glacier, Alaska, 1996 balance year

Science.gov (United States)

March, Rod S.

2003-01-01

The 1996 measured winter snow, maximum winter snow, net, and annual balances in the Gulkana Glacier Basin were evaluated on the basis of meteorological, hydrological, and glaciological data. Averaged over the glacier, the measured winter snow balance was 0.87 meter on April 18, 1996, 1.1 standard deviation below the long-term average; the maximum winter snow balance, 1.06 meters, was reached on May 28, 1996; and the net balance (from August 30, 1995, to August 24, 1996) was -0.53 meter, 0.53 standard deviation below the long-term average. The annual balance (October 1, 1995, to September 30, 1996) was -0.37 meter. Area-averaged balances were reported using both the 1967 and 1993 area altitude distributions (the numbers previously given in this abstract use the 1993 area altitude distribution). Net balance was about 25 percent less negative using the 1993 area altitude distribution than the 1967 distribution. Annual average air temperature was 0.9 degree Celsius warmer than that recorded with the analog sensor used since 1966. Total precipitation catch for the year was 0.78 meter, 0.8 standard deviations below normal. The annual average wind speed was 3.5 meters per second in the first year of measuring wind speed. Annual runoff averaged 1.50 meters over the basin, 1.0 standard deviation below the long-term average. Glacier-surface altitude and ice-motion changes measured at three index sites document seasonal ice-speed and glacier-thickness changes. Both showed a continuation of a slowing and thinning trend present in the 1990s. The glacier terminus and lower ablation area were defined for 1996 with a handheld Global Positioning System survey of 126 locations spread out over about 4 kilometers on the lower glacier margin. From 1949 to 1996, the terminus retreated about 1,650 meters for an average retreat rate of 35 meters per year.

Relationship between water quality of deep-groundwater and geology in non-volcanic areas in Japan

International Nuclear Information System (INIS)

Oyama, Yoichi; Takahashi, Masaaki; Tsukamoto, Hitoshi; Kazahaya, Kohei; Yasuhara, Masaya; Takahashi, Hiroshi; Morikawa, Noritoshi; Ohwada, Michiko; Shibahara, Akihiko; Inamura, Akihiko

2011-01-01

Geochemical characteristics in groundwater such as groundwater chemistry and physicochemical parameters are affected by their source and the interaction with rocks and minerals. We observed the relationships between groundwater chemistry of the deep-groundwater and the geology in non-volcanic areas in Japan using about 9300 of deep-groundwater data. A Geographical Information System (GIS) was used to extract data in non-volcanic areas and numbers of water data are about 5200. The data were further classified into four types of geology (sedimentary rock, accretionary complex, volcanic rock and plutonic rock). The pH, temperature and major ion concentrations among deep-groundwaters in each geology have been statistically analysed. Result shows that the total cation concentration of deep-groundwaters are significantly different between geology, and the average values are decreased in the order of the sedimentary rock (66.7 meq l -1 ), volcanic rock (43.0 meq l -1 ), accretionary complex (24.6 meq l -1 ), and plutonic rock (11.0 meq l -1 ). The average pH does not show the major difference between geology whereas the highest average temperature is found in volcanic rock. In addition, the all four major cations (Na, K, Mg, and Ca) show the highest average concentrations in sedimentary rock, within the highest average concentrations of major anions for Cl, SO 4 , and HCO 3 are found in sedimentary rock, volcanic rock and accretionary complex, respectively, indicating the difference of the influence on the anions varied with geology. The distribution of deep-groundwater that are dominated by each major anions implied that SO 4 -type groundwater in volcanic rocks are formed by the influence of Neogene volcanic rock (Green tuff). In addition, HCO 3 -type groundwater in accretionary complex found from Kinki to Shikoku regions are formed by the addition of CO 2 gases supplying not only from surface soil and carbonate minerals but from deep underground. (author)

Vegetation Activity Trend and Its Relationship with Climate Change in the Three Gorges Area, China

Directory of Open Access Journals (Sweden)

Guifeng Han

2013-01-01

Full Text Available Based on SPOT/VGT NDVI time series images from 1999 to 2009 in the Three Gorges Area (TGA, we detected vegetation activity and trends using two methods, the Mann-Kendall and Slope tests. The relationships between vegetation activity trends and annual average temperature and annual total precipitation were analyzed using observational data in seven typical meteorological stations. Vegetation activity presents a distinctive uptrend during the study period, especially in Fengjie, Yunyang, Wushan, Wuxi, and Badong counties located in the midstream of the Three Gorges Reservoir. However, in the Chongqing major area (CMA and its surrounding areas and Fuling, Yichang, and part of Wanzhou, vegetation activity shows a decreasing trend as a result of urban expansion. The NDVI has two fluctuation troughs in 2004 and 2006. The annual mean temperature presents a slight overall upward trend, but the annual total precipitation does not present a significant trend. And they almost have no significant correlations with the NDVI. Therefore, temperature and precipitation are not major influences on vegetation activity change. Instead, increasing vegetation cover benefits from a number of environment protection policies and management, and ecological construction is a major factor resulting in the upward trend. In addition, resettlement schemes mitigate the impact of human activity on vegetation activity.

Snow cover and temperature relationships in North America and Eurasia

Science.gov (United States)

Foster, J.; Owe, M.; Rango, A.

1983-01-01

In this study the snow cover extent during the autumn months in both North America and Eurasia has been related to the ensuing winter temperature as measured at several locations near the center of each continent. The relationship between autumn snow cover and the ensuing winter temperatures was found to be much better for Eurasia than for North America. For Eurasia the average snow cover extent during the autumn explained as much as 52 percent of the variance in the winter (December-February) temperatures compared to only 12 percent for North America. However, when the average winter snow cover was correlated with the average winter temperature it was found that the relationship was better for North America than for Eurasia. As much as 46 percent of the variance in the winter temperature was explained by the winter snow cover in North America compared to only 12 percent in Eurasia.

Assessing the permafrost temperature and thickness conditions favorable for the occurrence of gas hydrate in the Qinghai-Tibet Plateau

International Nuclear Information System (INIS)

Wu Qingbai; Jiang Guanli; Zhang Peng

2010-01-01

Permafrost accounts for about 52% of the total area of the Qinghai-Tibet Plateau, and the permafrost area is about 140 x 10 4 km 2 . The mean annual ground temperature of permafrost ranges from -0.1 to -5 deg. C, and lower than -5 deg. C at extreme high-mountains. Permafrost thickness ranges from 10 to 139.4 m by borehole data, and more than 200 m by geothermal gradients. The permafrost geothermal gradient ranges from 1.1 deg. C/100 m to 8.0 deg. C/100 m with an average of 2.9 deg. C/100 m, and the geothermal gradient of the soil beneath permafrost is about 2.8-8.5 deg. C/100 m with an average of 6.0 deg. C/100 m in the Qinghai-Tibet Plateau. For a minimum of permafrost geothermal gradients of 1.1 deg. C/100 m, the areas of the potential occurrence of methane hydrate (sI) is approximately estimated to be about 27.5% of the total area of permafrost regions in the Qinghai-Tibet Plateau. For an average of permafrost geothermal gradients of 2.9 deg. C/100 m, the areas of the potential occurrence of methane hydrate (sI) is approximately estimated about 14% of the total area of permafrost regions in the Qinghai-Tibet Plateau. For the sII hydrate, the areas of the potential occurrence of sII hydrate are more than that of sI methane hydrate.

How to average logarithmic retrievals?

Directory of Open Access Journals (Sweden)

B. Funke

2012-04-01

Full Text Available Calculation of mean trace gas contributions from profiles obtained by retrievals of the logarithm of the abundance rather than retrievals of the abundance itself are prone to biases. By means of a system simulator, biases of linear versus logarithmic averaging were evaluated for both maximum likelihood and maximum a priori retrievals, for various signal to noise ratios and atmospheric variabilities. These biases can easily reach ten percent or more. As a rule of thumb we found for maximum likelihood retrievals that linear averaging better represents the true mean value in cases of large local natural variability and high signal to noise ratios, while for small local natural variability logarithmic averaging often is superior. In the case of maximum a posteriori retrievals, the mean is dominated by the a priori information used in the retrievals and the method of averaging is of minor concern. For larger natural variabilities, the appropriateness of the one or the other method of averaging depends on the particular case because the various biasing mechanisms partly compensate in an unpredictable manner. This complication arises mainly because of the fact that in logarithmic retrievals the weight of the prior information depends on abundance of the gas itself. No simple rule was found on which kind of averaging is superior, and instead of suggesting simple recipes we cannot do much more than to create awareness of the traps related with averaging of mixing ratios obtained from logarithmic retrievals.

A quantitative study of eicosapentaenoic acid (EPA) production by Nannochloropsis gaditana for aquaculture as a function of dilution rate, temperature and average irradiance.

Science.gov (United States)

Camacho-Rodríguez, J; González-Céspedes, A M; Cerón-García, M C; Fernández-Sevilla, J M; Acién-Fernández, F G; Molina-Grima, E

2014-03-01

Different pilot-scale outdoor photobioreactors using medium recycling were operated in a greenhouse under different environmental conditions and the growth rates (0.1 to 0.5 day(-1)) obtained evaluated in order to compare them with traditional systems used in aquaculture. The annualized volumetric growth rate for Nannochloropsis gaditana was 0.26 g l(-1) day(-1) (peak 0.4 g l(-1) day(-1)) at 0.4 day(-1) in a 5-cm wide flat-panel bioreactor (FP-PBR). The biomass productivity achieved in this reactor was 10-fold higher than in traditional reactors, reaching values of 28 % and 45 % dry weight (d.w.) of lipids and proteins, respectively, with a 4.3 % (d.w.) content of eicosapentaenoic acid (EPA). A model for predicting EPA productivity from N. gaditana cultures that takes into account the existence of photolimitation and photoinhibition of growth under outdoor conditions is presented. The effect of temperature and average irradiance on EPA content is also studied. The maximum EPA productivity attained is 30 mg l(-1) day(-1).

Impact of Environmental Changes and Global Warming on Temperature in Pakistan

Directory of Open Access Journals (Sweden)

Ishtiaq Hassan

2011-01-01

Full Text Available Environmental changes and global warming have direct impact on human life. Estimation of these changes in various parameters of hydrologic cycle is necessary for future planning and development of a country. In this paper the impact of environmental changes and global warming on temperatures of Pakistan has been studied. The temperature changes in Pakistan have been extracted from simulations made using EdGCM model developed at Columbia University. Simulation study to the end of 21st century is executed using the model for GHG (Greenhouse Gases scenario with doubled_CO2 and scenario of Modern_Predicted SST (Sea Surface Temperature. The model analysis has been carried out for seasonal and annual changes for an average of last 5 years period from 2096-2100. Maps are generated to depict global temperature variations. The study divides Pakistan into five (05 main areas for twenty six (26 stations. A part-plan of globe focusing Pakistan is generated showing the five divisions for twenty six (26 data stations of Pakistan. This part plan is made compatible with grid-box resolution of EdGCM. Eagle-Point Engineering software has been used to generate isohyets of interval (0.5oC for downscaling GCM (Global Climate Model grid data to data stations. The station values of different seasons and annual changes are then compared with the values of base period data to determine changes in temperature. It is observed that impact of global environmental changes on temperature are higher (i.e. there is an increase in annual temperature for double_CO2 experiment at places near the Arabian Sea than areas located away from this sea. It is also observed that the temperature increase will be more in winter than that in other seasons for Pakistan.

Cell formation effects on the burning speeds and flame front area of synthetic gas at high pressures and temperatures

International Nuclear Information System (INIS)

Askari, Omid; Elia, Mimmo; Ferrari, Matthew; Metghalchi, Hameed

2017-01-01

Highlights: • Effect of cell formation on burning speed and flame surface area is investigated. • A new developed non-dimensional number called cellularity factor is introduced. • Cellular burning speed and mass burning rate are calculated using differential based multi-shell model. • Flame instability is studied using thermo-diffusive and hydrodynamics effects. • Power law correlations are developed for cellular burning speeds and mass burning rates. - Abstract: Cellular burning speeds and mass burning rates of premixed syngas/oxidizer/diluent (H_2/CO/O_2/He) have been determined at high pressures and temperatures over a wide range of equivalence ratios which are at engine-relevant conditions. Working on high pressure combustion helps to reduce the pollution and increase the energy efficiency in combustion devices. The experimental facilities consisted of two spherical and cylindrical chambers. The spherical chamber, which can withstand high pressures up to 400 atm, was used to collect pressure rise data due to combustion, to calculate cellular burning speed and mass burning rate. For flame structure and instability analysis the cylindrical chamber was used to take pictures of propagating flame using a high speed CMOS camera and a schlieren photography system. A new differential based multi-shell model based on pressure rise data was used to determine the cellular burning speed and mass burning rate. In this paper, cellular burning speed and mass burning rate of H_2/CO/O_2/He mixture have been measured for a wide range of equivalence ratios from 0.6 to 2, temperatures from 400 to 750 K and pressures from 2 to 50 atm for three hydrogen concentrations of 5, 10 and 25% in the syngas. The power law correlations for cellular burning speed and mass burning rate were developed as a function of equivalence ratio, temperature and pressure. In this study a new developed parameter, called cellularity factor, which indicates the cell formation effect on flame

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Key West Channel, 1991 - 2005 (NODC Accession 0012739)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Boca Grande Channel, 2004-2006 (NODC Accession 0014184)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Sand Key Lighthouse, 1990 - 2005 (NODC Accession 0012769)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Key West Channel, 2005 - 2007 (NODC Accession 0039986)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Sand Key Lighthouse, 2007 - 2010 (NODC Accession 0093065)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Card Sound Bridge, 2004 - 2006 (NODC Accession 0014266)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Sand Key Lighthouse, 2005 - 2007 (NODC Accession 0040080)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at 9-Ft Shoal, 2007-2010 (NODC Accession 0092549)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Ball Buoy Reef, 1990 - 1998 (NODC Accession 0002781)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Bicentennial Coral Head, 1998 - 2006 (NODC Accession 0039481)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Bahia Honda Bridge, 2007-2011 (NODC Accession 0093018)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Snake Creek Bridge, 1989 - 2005 (NODC accession 0013148)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Harbor Key Bank, 1992 - 1997 (NODC Accession 0013553)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Sombrero Reef Lighthouse, 1991-2005 (NODC Accession 0013726)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at 7-mile Bridge, 2005 - 2007 (NODC Accession 0039469)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at 7-mile Bridge, 2007-2010 (NODC Accession 0092548)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at 9-FT Shoal, 2005-2007 (NODC Accession 0039533)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Bicentennial Coral Head, 2006 - 2007 (NODC Accession 0039817)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Boca Grande Channel, 2006 - 2007 (NODC Accession 0039818)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Snake Creek Bridge, 1989 - 2005 (NODC Accession 0013148)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Continuous bottom temperature measurements in strategic areas of the Florida Reef Tract at Bicentennial Coral Head, 2007-2009 (NODC Accession 0090835)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The purpose of this project is to document bottom seawater temperature in strategic areas of the Florida Reef Tract on a continuing basis and make that information...

Spot temperatures and area coverages on active dwarf stars

Science.gov (United States)

Sarr, Steven H.; Neff, James E.

1990-01-01

Two active K dwarfs are examined to determine the temperatures of the stars and to estimate the locations and sizes of cool spots on the stellar surfaces. Two wavelength regions with TiO absorption bands at different temperature sensitivities are modeled simultaneously using the method developed by Huenemoerder and Ramsey (1987). The spectrum of BD +26deg730 shows excess absorption in the TiO band, and the absence of the 8860 A band in HD 82558 indicates that its spots are warmer than those of BD +26deg730.

A method of surface area measurement of fuel materials by fission gas release at low temperature

International Nuclear Information System (INIS)

Kaimal, K.N.G.; Naik, M.C.; Paul, A.R.; Venkateswarlu, K.S.

1989-01-01

The present report deals with the development of a method for surface area measurement of nuclear fuel as well as fissile doped materials by fission gas release study at low temperature. The method is based on the evaluation of knock-out release rate of fission 133 Xe from irradiated fuel after sufficient cooling to decay the short lived activity. The report also describes the fabrication of an ampoule breaker unit for such study. Knock-out release rate of 133 Xe has been studied from UO 2 powders having varying surface area 'S' ranging from 270 cm 2 /gm to 4100 cm 2 /gm at two fissioning rates 10 12 f/cm 3 . sec. and 3.2x10 10 f/cm.sec. A relation between K and A has been established and discussed in this report. (author). 6 refs

Oregon Low-Temperature-Resource Assessment Program. Final technical report

Energy Technology Data Exchange (ETDEWEB)

Priest, G.R.; Black, G.L.; Woller, N.M.

1981-01-01

Numerous low-temperature hydrothermal systems are available for exploitation throughout the Cascades and eastern Oregon. All of these areas have heat flow significantly higher than crustal averages and many thermal aquifers. In northeastern Oregon, low temperature geothermal resources are controlled by regional stratigraphic aquifers of the Columbia River Basalt Group at shallow depths and possibly by faults at greater depths. In southeastern Oregon most hydrothermal systems are of higher temperature than those of northeastern Oregon and are controlled by high-angle fault zones and layered volcanic aquifers. The Cascades have very high heat flow but few large population centers. Direct use potential in the Cascades is therefore limited, except possibly in the cities of Oakridge and Ashland, where load may be great enough to stimulate development. Absence of large population centers also inhibits initial low temperature geothermal development in eastern Oregon. It may be that uses for the abundant low temperature geothermal resources of the state will have to be found which do not require large nearby population centers. One promising use is generation of electricity from freon-based biphase electrical generators. These generators will be installed on wells at Vale and Lakeview in the summer of 1982 to evaluate their potential use on geothermal waters with temperatures as low as 80/sup 0/C (176/sup 0/F).

Dynamical calculation of nuclear temperature

International Nuclear Information System (INIS)

Zheng Yuming

1998-01-01

A new dynamical approach for measuring the temperature of a Hamiltonian dynamical system in the microcanonical ensemble of thermodynamics is presented. It shows that under the hypothesis of ergodicity the temperature can be computed as a time average of a function on the energy surface. This method not only yields an efficient computational approach for determining the temperature, but also provides an intrinsic link between dynamical system theory and the statistical mechanics of Hamiltonian system

The Temperature Dependence of the Debye-Waller Factor of Magnesium

DEFF Research Database (Denmark)

Sledziewska-Blocka, D.; Lebech, Bente

1976-01-01

The temperature dependence of the average Debye-Waller factor for magnesium was measured by means of neutron diffraction spectrometry. The experimental results obtained in the temperature range from 5 to 256 K are compared with theoretical calculations, using the harmonic and quasi-harmonic appro......The temperature dependence of the average Debye-Waller factor for magnesium was measured by means of neutron diffraction spectrometry. The experimental results obtained in the temperature range from 5 to 256 K are compared with theoretical calculations, using the harmonic and quasi......-harmonic approximations and results of previous experiments....

Genetic aftereffects of increased temperature in Larix

Science.gov (United States)

Michael S. Greenwood; Keith W. Hutchinson

1996-01-01

We tested the hypothesis that temperature during gametogenesis and embryogenesis can affect progeny genotype and phenotype. Identical crosses were made among cloned parents of Larix spp. inside and outside a greenhouse, where the temperature inside averaged 4?C above the outside temperature. Significant growth differences as a function of crossing...

Temporal trends in United States dew point temperatures

Science.gov (United States)

Robinson, Peter J.

2000-07-01

In this study, hourly data for the 1951-1990 period for 178 stations in the coterminous United States were used to establish temporal trends in dew point temperature. Although the data had been quality controlled previously (Robinson, 1998. Monthly variations of dew point temperatures in the coterminous United States. International Journal of Climatology 18: 1539-1556), comparisons of values between nearby stations suggested that instrumental changes, combined with locational changes, may have modified the results by as much as 1°C during the 40-year period. Nevertheless, seasonally averaged results indicated an increase over much of the area, of slightly over 1°C/100 years in spring and autumn, slightly less than this in summer. Winter displayed a drying of over 1°C/100 years. When only the 1961-1990 period was considered, the patterns were similar and trends increased by approximately 1-2°C/100 years, except in autumn, which displayed a slight drying. Analyses for specific stations indicated periods of both increasing and decreasing Td, the change between them varying with observation hour. No single change point was common over a wide area, although January commonly indicated maximum values early in the period in the east and west, and much later in the north-central portion. Rates of increase were generally higher in daytime than at night, especially in summer. Investigation of the inter-decadal differences in dew point, as a function of wind conditions, indicated that changes during calm conditions were commonly similar in magnitude to that of the overall average changes, suggesting an important role for the local hydrologic cycle in driving changes. Other inter-decadal changes could be attributed to the changes in the frequency and moisture content of invading air-streams. This was particularly clear for the changes in north-south flow in the interior.

A new weighted mean temperature model in China

Science.gov (United States)

Liu, Jinghong; Yao, Yibin; Sang, Jizhang

2018-01-01

The Global Positioning System (GPS) has been applied in meteorology to monitor the change of Precipitable Water Vapor (PWV) in atmosphere, transformed from Zenith Wet Delay (ZWD). A key factor in converting the ZWD into the PWV is the weighted mean temperature (Tm), which has a direct impact on the accuracy of the transformation. A number of Bevis-type models, like Tm -Ts and Tm -Ts,Ps type models, have been developed by statistics approaches, and are not able to clearly depict the relationship between Tm and the surface temperature, Ts . A new model for Tm , called weighted mean temperature norm model (abbreviated as norm model), is derived as a function of Ts , the lapse rate of temperature, δ, the tropopause height, htrop , and the radiosonde station height, hs . It is found that Tm is better related to Ts through an intermediate temperature. The small effects of lapse rate can be ignored and the tropopause height be obtained from an empirical model. Then the norm model is reduced to a simplified form, which causes fewer loss of accuracy and needs two inputs, Ts and hs . In site-specific fittings, the norm model performs much better, with RMS values reduced averagely by 0.45 K and the Mean of Absolute Differences (MAD) values by 0.2 K. The norm model is also found more appropriate than the linear models to fit Tm in a large area, not only with the RMS value reduced from 4.3 K to 3.80 K, correlation coefficient R2 increased from 0.84 to 0.88, and MAD decreased from 3.24 K to 2.90 K, but also with the distribution of simplified model values to be more reasonable. The RMS and MAD values of the differences between reference and computed PWVs are reduced by on average 16.3% and 14.27%, respectively, when using the new norm models instead of the linear model.

Temperature-induced structural changes in fluorozirconate glasses and liquids

International Nuclear Information System (INIS)

Sen, S.; Youngman, R.E.

2002-01-01

The atomic structure and its temperature dependence in fluorozirconate glasses and supercooled liquids have been studied with high-resolution and high-temperature 19 F and 23 Na nuclear-magnetic-resonance (NMR) spectroscopy. The 19 F NMR spectra in these glasses show the presence of multiple F environments. Temperature dependence of the 19 F magic-angle-spinning NMR spectra indicates a progressive change in the average F coordination environment in the glass structure, besides motional narrowing due to substantial mobility of F - ions. The observed change in the average 19 F NMR chemical shift is consistent with progressive breaking of the Zr-F-Zr linkages in the glass structure with increasing temperature. The onset of such a change in F speciation is observed at temperatures well below T g . This result is evidence of changes in the average equilibrium structure in an inorganic glass-forming liquid at T g , albeit on a local scale. The 23 Na NMR spectra indicate that the cations in these glasses become significantly mobile only at temperatures T≥T g , which allows for the onset of global structural relaxation and viscous flow

On Averaging Rotations

DEFF Research Database (Denmark)

Gramkow, Claus

2001-01-01

In this paper two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very often the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong ...... approximations to the Riemannian metric, and that the subsequent corrections are inherent in the least squares estimation.......In this paper two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very often the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...

FDTD analysis of body-core temperature elevation in children and adults for whole-body exposure

International Nuclear Information System (INIS)

Hirata, Akimasa; Asano, Takayuki; Fujiwara, Osamu

2008-01-01

The temperature elevations in anatomically based human phantoms of an adult and a 3-year-old child were calculated for radio-frequency whole-body exposure. Thermoregulation in children, however, has not yet been clarified. In the present study, we developed a computational thermal model of a child that is reasonable for simulating body-core temperature elevation. Comparison of measured and simulated temperatures revealed thermoregulation in children to be similar to that of adults. Based on this finding, we calculated the body-core temperature elevation in a 3-year-old child and an adult for plane-wave exposure at the basic restriction in the international guidelines. The body-core temperature elevation in the 3-year-old child phantom was 0.03 deg. C at a whole-body-averaged specific absorption rate of 0.08 W kg -1 , which was 35% smaller than in the adult female. This difference is attributed to the child's higher body surface area-to-mass ratio

FDTD analysis of body-core temperature elevation in children and adults for whole-body exposure

Energy Technology Data Exchange (ETDEWEB)

Hirata, Akimasa; Asano, Takayuki; Fujiwara, Osamu [Department of Computer Science and Engineering, Nagoya Institute of Technology (Japan)], E-mail: ahirata@nitech.ac.jp

2008-09-21

The temperature elevations in anatomically based human phantoms of an adult and a 3-year-old child were calculated for radio-frequency whole-body exposure. Thermoregulation in children, however, has not yet been clarified. In the present study, we developed a computational thermal model of a child that is reasonable for simulating body-core temperature elevation. Comparison of measured and simulated temperatures revealed thermoregulation in children to be similar to that of adults. Based on this finding, we calculated the body-core temperature elevation in a 3-year-old child and an adult for plane-wave exposure at the basic restriction in the international guidelines. The body-core temperature elevation in the 3-year-old child phantom was 0.03 deg. C at a whole-body-averaged specific absorption rate of 0.08 W kg{sup -1}, which was 35% smaller than in the adult female. This difference is attributed to the child's higher body surface area-to-mass ratio.

FDTD analysis of body-core temperature elevation in children and adults for whole-body exposure.

Science.gov (United States)

Hirata, Akimasa; Asano, Takayuki; Fujiwara, Osamu

2008-09-21

The temperature elevations in anatomically based human phantoms of an adult and a 3-year-old child were calculated for radio-frequency whole-body exposure. Thermoregulation in children, however, has not yet been clarified. In the present study, we developed a computational thermal model of a child that is reasonable for simulating body-core temperature elevation. Comparison of measured and simulated temperatures revealed thermoregulation in children to be similar to that of adults. Based on this finding, we calculated the body-core temperature elevation in a 3-year-old child and an adult for plane-wave exposure at the basic restriction in the international guidelines. The body-core temperature elevation in the 3-year-old child phantom was 0.03 degrees C at a whole-body-averaged specific absorption rate of 0.08 W kg(-1), which was 35% smaller than in the adult female. This difference is attributed to the child's higher body surface area-to-mass ratio.

Kumaraswamy autoregressive moving average models for double bounded environmental data

Science.gov (United States)

Bayer, Fábio Mariano; Bayer, Débora Missio; Pumi, Guilherme

2017-12-01

In this paper we introduce the Kumaraswamy autoregressive moving average models (KARMA), which is a dynamic class of models for time series taking values in the double bounded interval (a,b) following the Kumaraswamy distribution. The Kumaraswamy family of distribution is widely applied in many areas, especially hydrology and related fields. Classical examples are time series representing rates and proportions observed over time. In the proposed KARMA model, the median is modeled by a dynamic structure containing autoregressive and moving average terms, time-varying regressors, unknown parameters and a link function. We introduce the new class of models and discuss conditional maximum likelihood estimation, hypothesis testing inference, diagnostic analysis and forecasting. In particular, we provide closed-form expressions for the conditional score vector and conditional Fisher information matrix. An application to environmental real data is presented and discussed.

Measurement of the average mass of proteins adsorbed to a nanoparticle by using a suspended microchannel resonator.

Science.gov (United States)

Nejadnik, M Reza; Jiskoot, Wim

2015-02-01

We assessed the potential of a suspended microchannel resonator (SMR) to measure the adsorption of proteins to nanoparticles. Standard polystyrene beads suspended in buffer were weighed by a SMR system. Particle suspensions were mixed with solutions of bovine serum albumin (BSA) or monoclonal human antibody (IgG), incubated at room temperature for 3 h and weighed again with SMR. The difference in buoyant mass of the bare and protein-coated polystyrene beads was calculated into real mass of adsorbed proteins. The average surface area occupied per protein molecule was calculated, assuming a monolayer of adsorbed protein. In parallel, dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), and zeta potential measurements were performed. SMR revealed a statistically significant increase in the mass of beads because of adsorption of proteins (for BSA and IgG), whereas DLS and NTA did not show a difference between the size of bare and protein-coated beads. The change in the zeta potential of the beads was also measurable. The surface area occupied per protein molecule was in line with their known size. Presented results show that SMR can be used to measure the mass of adsorbed protein to nanoparticles with a high precision in the presence of free protein. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

On the speed towards the mean for continuous time autoregressive moving average processes with applications to energy markets

International Nuclear Information System (INIS)

Benth, Fred Espen; Taib, Che Mohd Imran Che

2013-01-01

We extend the concept of half life of an Ornstein–Uhlenbeck process to Lévy-driven continuous-time autoregressive moving average processes with stochastic volatility. The half life becomes state dependent, and we analyze its properties in terms of the characteristics of the process. An empirical example based on daily temperatures observed in Petaling Jaya, Malaysia, is presented, where the proposed model is estimated and the distribution of the half life is simulated. The stationarity of the dynamics yield futures prices which asymptotically tend to constant at an exponential rate when time to maturity goes to infinity. The rate is characterized by the eigenvalues of the dynamics. An alternative description of this convergence can be given in terms of our concept of half life. - Highlights: • The concept of half life is extended to Levy-driven continuous time autoregressive moving average processes • The dynamics of Malaysian temperatures are modeled using a continuous time autoregressive model with stochastic volatility • Forward prices on temperature become constant when time to maturity tends to infinity • Convergence in time to maturity is at an exponential rate given by the eigenvalues of the model temperature model

Causes of Greenland temperature variability over the past 4000 yr: implications for northern hemispheric temperature changes

Directory of Open Access Journals (Sweden)

T. Kobashi

2013-10-01

Full Text Available Precise understanding of Greenland temperature variability is important in two ways. First, Greenland ice sheet melting associated with rising temperature is a major global sea level forcing, potentially affecting large populations in coming centuries. Second, Greenland temperatures are highly affected by North Atlantic Oscillation/Arctic Oscillation (NAO/AO and Atlantic multidecadal oscillation (AMO. In our earlier study, we found that Greenland temperature deviated negatively (positively from northern hemispheric (NH temperature trend during stronger (weaker solar activity owing to changes in atmospheric/oceanic changes (e.g. NAO/AO over the past 800 yr (Kobashi et al., 2013. Therefore, a precise Greenland temperature record can provide important constraints on the past atmospheric/oceanic circulation in the region and beyond. Here, we investigated Greenland temperature variability over the past 4000 yr reconstructed from argon and nitrogen isotopes from trapped air in a GISP2 ice core, using a one-dimensional energy balance model with orbital, solar, volcanic, greenhouse gas, and aerosol forcings. The modelled northern Northern Hemisphere (NH temperature exhibits a cooling trend over the past 4000 yr as observed for the reconstructed Greenland temperature through decreasing annual average insolation. With consideration of the negative influence of solar variability, the modelled and observed Greenland temperatures agree with correlation coefficients of r = 0.34–0.36 (p = 0.1–0.04 in 21 yr running means (RMs and r = 0.38–0.45 (p = 0.1–0.05 on a centennial timescale (101 yr RMs. Thus, the model can explain 14 to 20% of variance of the observed Greenland temperature in multidecadal to centennial timescales with a 90–96% confidence interval, suggesting that a weak but persistent negative solar influence on Greenland temperature continued over the past 4000 yr. Then, we estimated the distribution of multidecadal NH and northern high

Health heat stress in the Porto Metropolitan Area – a matter of temperature or inadequate adaptation?

Directory of Open Access Journals (Sweden)

Monteiro, Ana

2014-09-01

Full Text Available The aim of this contribution is to understand the negative outcomes for human health during hot weather in a Mediterranean urban environment. Examining seasonal variations of thermal comfort in Porto, by Physiologically Equivalent Temperature (PET, and comparing expected and observed daily mortality (all causes and morbidity (all causes, respiratory and circulatory diseases, suggests that in southern Europe, people’s adaptation techniques for reducing heat stress and associated health risks need to be developed much further. Research already done in Porto shows that social and economic vulnerability must be included alongside with individual characteristics, like age, gender or genetics, when defining the thresholds above which negative health impacts begin to become severe. Findings from Porto show that a climate risk map is needed for every metropolitan area, with sufficient detail to give locally appropriate temperature thresholds taking into account both the local climate and the socio-economic conditions of every sector of the urban environment.

The influence of air temperature inversions on snowmelt and glacier mass-balance simulations, Ammassalik island, SE Greenland

Energy Technology Data Exchange (ETDEWEB)

Mernild, Sebastian Haugard [Los Alamos National Laboratory; Liston, Glen [COLORADO STATE UNIV.

2009-01-01

In many applications, a realistic description of air temperature inversions is essential for accurate snow and glacier ice melt, and glacier mass-balance simulations. A physically based snow-evolution modeling system (SnowModel) was used to simulate eight years (1998/99 to 2005/06) of snow accumulation and snow and glacier ice ablation from numerous small coastal marginal glaciers on the SW-part of Ammassalik Island in SE Greenland. These glaciers are regularly influenced by inversions and sea breezes associated with the adjacent relatively low temperature and frequently ice-choked fjords and ocean. To account for the influence of these inversions on the spatiotemporal variation of air temperature and snow and glacier melt rates, temperature inversion routines were added to MircoMet, the meteorological distribution sub-model used in SnowModel. The inversions were observed and modeled to occur during 84% of the simulation period. Modeled inversions were defined not to occur during days with strong winds and high precipitation rates due to the potential of inversion break-up. Field observations showed inversions to extend from sea level to approximately 300 m a.s.l., and this inversion level was prescribed in the model simulations. Simulations with and without the inversion routines were compared. The inversion model produced air temperature distributions with warmer lower elevation areas and cooler higher elevation areas than without inversion routines due to the use of cold sea-breeze base temperature data from underneath the inversion. This yielded an up to 2 weeks earlier snowmelt in the lower areas and up to 1 to 3 weeks later snowmelt in the higher elevation areas of the simulation domain. Averaged mean annual modeled surface mass-balance for all glaciers (mainly located above the inversion layer) was -720 {+-} 620 mm w.eq. y{sup -1} for inversion simulations, and -880 {+-} 620 mm w.eq. y{sup -1} without the inversion routines, a difference of 160 mm w.eq. y

Urban climate effects on extreme temperatures in Madison, Wisconsin, USA

Science.gov (United States)

Schatz, Jason; Kucharik, Christopher J.

2015-09-01

As climate change increases the frequency and intensity of extreme heat, cities and their urban heat island (UHI) effects are growing, as are the urban populations encountering them. These mutually reinforcing trends present a growing risk for urban populations. However, we have limited understanding of urban climates during extreme temperature episodes, when additional heat from the UHI may be most consequential. We observed a historically hot summer and historically cold winter using an array of up to 150 temperature and relative humidity sensors in and around Madison, Wisconsin, an urban area of population 402 000 surrounded by lakes and a rural landscape of agriculture, forests, wetlands, and grasslands. In the summer of 2012 (third hottest since 1869), Madison’s urban areas experienced up to twice as many hours ⩾32.2 °C (90 °F), mean July TMAX up to 1.8 °C higher, and mean July TMIN up to 5.3 °C higher than rural areas. During a record setting heat wave, dense urban areas spent over four consecutive nights above the National Weather Service nighttime heat stress threshold of 26.7 °C (80 °F), while rural areas fell below 26.7 °C nearly every night. In the winter of 2013-14 (coldest in 35 years), Madison’s most densely built urban areas experienced up to 40% fewer hours ⩽-17.8 °C (0 °F), mean January TMAX up to 1 °C higher, and mean January TMIN up to 3 °C higher than rural areas. Spatially, the UHI tended to be most intense in areas with higher population densities. Temporally, both daytime and nighttime UHIs tended to be slightly more intense during more-extreme heat days compared to average summer days. These results help us understand the climates for which cities must prepare in a warming, urbanizing world.