scholarly journals Surface Temperature Simulation of Lunar Dayside and Its Geological Applications: A Case in Sinus Iridum

Sensors ◽  
2019 ◽  
Vol 19 (24) ◽  
pp. 5545 ◽  
Author(s):  
Jidong Zhang ◽  
Jinsong Ping ◽  
Zhaofa Zeng ◽  
Yongzhang Yang ◽  
Xiangyue Li ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Large Scale ◽  
Diffuse Reflection ◽  
Lunar Regolith ◽  
Microwave Radiometer ◽  
Spectral Emissivity ◽  
Superficial Layer ◽  
Observation Time ◽  
Local Times ◽  
Physical Parameters

Lunar surface temperature is one of the fundamental thermophysical parameters of the lunar regolith, which is of great significance to the interpretation of remote-sensing thermal data. In this study, a daytime surface temperature model is established focusing on the lunar superficial layer with high spatial-temporal resolution. The physical parameters at the time of interest are adopted, including effective solar irradiance, lunar libration, large-scale topographic shading, and surrounding diffuse reflection. Thereafter, the 1/64° temperature distributions at five local times are quantitatively generated and analyzed in Sinus Iridum. Also, combined with Chang’E-2 microwave radiometer (CELMS) data and Diviner thermal infrared (TIR) data, the spectral emissivity distributions are estimated as a potential geological application of the simulated surface temperature. The results are as follows: (1) daytime surface temperature in Sinus Iridum is significantly affected by the local topography and observation time, and the influence of diffuse reflection energy is obvious; (2) the emissivity distributions provide a new way to understand the thermophysical properties difference of lunar regolith at different depths; (3) the influence of lunar orbiting revolution and precession on surface temperature should be analyzed carefully, which shows the importance of using the parameters at the time of interest.

scholarly journals Influence of surface topography on brightness temperature of the regions along the road

2020 ◽  
Vol 145 ◽  
pp. 02025
Author(s):  
Gang Xu ◽  
Ying Yang ◽  
Zhiguo Meng
Keyword(s):  
Surface Temperature ◽  
Brightness Temperature ◽  
Surface Topography ◽  
Microwave Radiometer ◽  
Physical Parameters ◽  
Surface Slope ◽  
Internal Temperature ◽  
Low Latitude ◽  
The Road ◽  
Macro Scale

Internal temperature of the road is one of the important indicators to evaluate the safety of the road, and the microwave radiometer data is only efficient way to acquire the internal temperatures. This study is to evaluate the influence of the surface topography on the brightness temperature (TB) measured the microwave radiometer data. The results are as follows. (1) The surface slope (θ) and its direction play the important roles on the TB. (2) The influence of θ on TB is weaker compared to that of the surface temperature. (3) At least in low latitude regions, the influence of topography on the TB can be neglected in macro scale. The conclusions are essential to better understand the internal physical parameters of the road with the microwave radiometer data.

scholarly journals Comparison of Some Physical Parameters of Whole and Scored Lisinopril and Lisinopril/Hydrochlorthiazide Tablets

2008 ◽  
Vol 8 (4) ◽  
pp. 391-395 ◽  
Author(s):  
Edina Vranić ◽  
Alija Uzunović
Keyword(s):  
Large Scale ◽  
Testing Procedure ◽  
Physical Parameters ◽  
Hardness Testing ◽  
Disintegration Time ◽  
Adequate Dose ◽  
Response Information ◽  
Tablet Splitting ◽  
Good Patient Compliance ◽  
Accepted Practice

Tablets are one of the most popular and preferred solid dosage forms because they can be accurately dosed, easily manufactured and packaged on a large scale, have good physical and chemical stability, and can contribute to good patient compliance given their ease of administration. The ability to match doses to patients depends on the availability of multiple dose sizes and adequate dose-response information. These are not always provided, so splitting of the tablets is sometimes necessary, Tablet splitting is an accepted practice in dispensing medication, It has been used when a dosage form of the required strength is not available commercially. The aim of our study was to compare some physical parameters of whole and scored lisinopril and lisinopril/hydrochlorthiazide tablets and to accept or exclude their influence on the obtaining of required dosage.According to the results obtained, we may conclude that tablets from batch “I” “IL “III” and “IV” satisfied pharmacopeial requirements concerning crushing strength, friability, disintegration time and mass uniformity. The hardness testing showed acceptable reproducibility and indicate that the data variation was primarily from the irreversible changes in the structure of tablet samples. The act of compacting powders stores energy within the tablets, by shifting or compressing the intermolecular bonds within the particles. The tablets have a natural tendency to relax once pressure is removed, and this tendency works against the interparticle bonding formed during compression. Hardness testing procedure causes irreversible changes in this structure.

scholarly journals Cities Exacerbate Climate Warming

Urban Science ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 27
Author(s):  
Lahouari Bounoua ◽  
Kurtis Thome ◽  
Joseph Nigro
Keyword(s):  
Surface Temperature ◽  
Land Surface ◽  
Large Scale ◽  
Climate Models ◽  
Warming Trend ◽  
Climate Mitigation ◽  
Temperature Changes ◽  
Surface Warming ◽  
The Us

Urbanization is a complex land transformation not explicitly resolved within large-scale climate models. Long-term timeseries of high-resolution satellite data are essential to characterize urbanization within land surface models and to assess its contribution to surface temperature changes. The potential for additional surface warming from urbanization-induced land use change is investigated and decoupled from that due to change in climate over the continental US using a decadal timescale. We show that, aggregated over the US, the summer mean urban-induced surface temperature increased by 0.15 °C, with a warming of 0.24 °C in cities built in vegetated areas and a cooling of 0.25 °C in cities built in non-vegetated arid areas. This temperature change is comparable in magnitude to the 0.13 °C/decade global warming trend observed over the last 50 years caused by increased CO2. We also show that the effect of urban-induced change on surface temperature is felt above and beyond that of the CO2 effect. Our results suggest that climate mitigation policies must consider urbanization feedback to put a limit on the worldwide mean temperature increase.

Interannual Variability of North American Winter Temperature Extremes and Its Associated Circulation Anomalies in Observations and CMIP5 Simulations

2020 ◽  
Vol 33 (3) ◽  
pp. 847-865 ◽  
Author(s):  
B. Yu ◽  
H. Lin ◽  
V. V. Kharin ◽  
X. L. Wang
Keyword(s):  
North America ◽  
Surface Temperature ◽  
Atmospheric Circulation ◽  
North American ◽  
North Pacific ◽  
Large Scale ◽  
Temperature Extremes ◽  
Temperature Extreme ◽  
Central Canada ◽  
Leading Mode

AbstractThe interannual variability of wintertime North American surface temperature extremes and its generation and maintenance are analyzed in this study. The leading mode of the temperature extreme anomalies, revealed by empirical orthogonal function (EOF) analyses of December–February mean temperature extreme indices over North America, is characterized by an anomalous center of action over western-central Canada. In association with the leading mode of temperature extreme variability, the large-scale atmospheric circulation features an anomalous Pacific–North American (PNA)-like pattern from the preceding fall to winter, which has important implications for seasonal prediction of North American temperature extremes. A positive PNA pattern leads to more warm and fewer cold extremes over western-central Canada. The anomalous circulation over the PNA sector drives thermal advection that contributes to temperature anomalies over North America, as well as a Pacific decadal oscillation (PDO)-like sea surface temperature (SST) anomaly pattern in the midlatitude North Pacific. The PNA-like circulation anomaly tends to be supported by SST warming in the tropical central-eastern Pacific and a positive synoptic-scale eddy vorticity forcing feedback on the large-scale circulation over the PNA sector. The leading extreme mode–associated atmospheric circulation patterns obtained from the observational and reanalysis data, together with the anomalous SST and synoptic eddy activities, are reasonably well simulated in most CMIP5 models and in the multimodel mean. For most models considered, the simulated patterns of atmospheric circulation, SST, and synoptic eddy activities have lower spatial variances than the corresponding observational and reanalysis patterns over the PNA sector, especially over the North Pacific.

A Novel Real-Time Thermal Analysis and Layer Time Control Framework for Large Scale Additive Manufacturing

2020 ◽  
Author(s):  
Sepehr Fathizadan ◽  
Feng Ju ◽  
Kyle Rowe ◽  
Alex Fiechter ◽  
Nils Hofmann
Keyword(s):  
Additive Manufacturing ◽  
Surface Temperature ◽  
Real Time ◽  
Large Scale ◽  
Production Efficiency ◽  
Control Method ◽  
Data Extraction ◽  
Critical Role ◽  
Imaging Data ◽  
Time Data

Abstract Production efficiency and product quality need to be addressed simultaneously to ensure the reliability of large scale additive manufacturing. Specifically, print surface temperature plays a critical role in determining the quality characteristics of the product. Moreover, heat transfer via conduction as a result of spatial correlation between locations on the surface of large and complex geometries necessitates the employment of more robust methodologies to extract and monitor the data. In this paper, we propose a framework for real-time data extraction from thermal images as well as a novel method for controlling layer time during the printing process. A FLIR™ thermal camera captures and stores the stream of images from the print surface temperature while the Thermwood Large Scale Additive Manufacturing (LSAM™) machine is printing components. A set of digital image processing tasks were performed to extract the thermal data. Separate regression models based on real-time thermal imaging data are built on each location on the surface to predict the associated temperatures. Subsequently, a control method is proposed to find the best time for printing the next layer given the predictions. Finally, several scenarios based on the cooling dynamics of surface structure were defined and analyzed, and the results were compared to the current fixed layer time policy. It was concluded that the proposed method can significantly increase the efficiency by reducing the overall printing time while preserving the quality.

Large-Scale Features of Synchronous Variability of the Winter Surface Temperature in the Barents and Black Seas

2021 ◽  
Vol 501 (1) ◽  
pp. 989-993
Author(s):  
A. A. Sizov ◽  
T. M. Bayankina ◽  
V. L. Pososhkov ◽  
A. E. Anisimov
Keyword(s):  
Surface Temperature ◽  
Large Scale

Research on Measurement of Spectral Emissivity Based on Fourier Infrared Spectrometer

2013 ◽  
Author(s):  
Kai Yue ◽  
Yongjian Niu ◽  
Xiaoming Guo ◽  
Xinxin Zhang
Keyword(s):  
Heat Transfer ◽  
Surface Temperature ◽  
Measurement Method ◽  
Measurement Accuracy ◽  
Background Radiation ◽  
Radiation Heat Transfer ◽  
Spectral Emissivity ◽  
Radiation Heat ◽  
Radiation Noise ◽  
Emissivity Measurement

As one of the basic parameters characterizing the radiation heat transfer of material surface, the emissivity is of important significance to perform non-contact thermometry research. Comparing with the traditional measurement method, measurement method of spectral emissivity based on the Fourier spectrometer has many advantages such as high accuracy and fast measurement. However, the measurement accuracy is subject to the influence of the radiant energy and the spectrometer electromagnetic radiation noise resulted from the environment. In this study, the geometric factor of the sample was defined and the reflectance of the background radiation in the surface of the sample was applied to accurately determine the energy of the radiation received on the detector. An emissivity measurement model was established and a mathematical formula was derived in this study to eliminate the influence of the background radiation noise. To improve the measurement accuracy of the surface temperature of samples, a heat conduction model is established so that the radiation heat transfer of the sample surface can be calculated and the surface temperature of the sample was obtained by equilibrium calculation. Moreover, we conducted emissivity measurement of black paint samples with high emissivity using the Fourier spectrometer and the proposed model is proven valid. Comparing the experimental results modified by the eliminating calculation formula with the experimental data obtained by the monochromator, it was found that there was good qualitative agreement between two sets of results.

scholarly journals Scaling of separated shear layers: an investigation of mass entrainment

2017 ◽  
Vol 826 ◽  
pp. 851-887 ◽  
Author(s):  
Francesco Stella ◽  
Nicolas Mazellier ◽  
Azeddine Kourta
Keyword(s):  
Shear Layer ◽  
Large Scale ◽  
Separated Flow ◽  
Layer Growth ◽  
Upper And Lower Bounds ◽  
Stream Velocity ◽  
Physical Parameters ◽  
Separated Shear Layer ◽  
Mass Entrainment ◽  
Recirculation Length

We report an experimental investigation of the separating/reattaching flow over a descending ramp with a $25^{\circ }$ expansion angle. Emphasis is given to mass entrainment through the boundaries of the separated shear layer emanating from the upper edge of the ramp. For this purpose, the turbulent/non-turbulent interface and the separation line inferred from image-based analysis are used respectively to mark the upper and lower bounds of the separated shear layer. The main objective of this study is to identify the physical parameters that scale the development of the separated shear layer, by giving a specific emphasis to the investigation of mass entrainment. Our results emphasise the multiscale nature of mass entrainment through the separated shear layer. The recirculation length $L_{R}$, step height $h$ and free-stream velocity $U_{\infty }$ are the dominant scales that organise the separated flow (and related large-scale quantities as pressure distribution or shear layer growth rate) and set mean mass fluxes. However, local viscous mechanisms seem to be responsible for most of local mass entrainment. Furthermore, it is shown that large-scale mass entrainment is driven by incoming boundary layer properties, since $L_{R}$ scales with $Re_{\unicode[STIX]{x1D703}}$, and in particular by its turbulent state. Surprisingly, the relationships evidenced in this study suggest that these dependencies are established over a large distance upstream of separation and that they might also extend to small scales, at which viscous entrainment is dominant. If confirmed by additional studies, our findings would open new perspectives for designing effective separation control systems.

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