Water Temperature Observation by Coastal Acoustic Tomography in Artificial Upwelling Area

Artificial upwelling is a geoengineering method to repair and improve marine ecosystems, and its operation requires long-term and continuous temperature field observation. However, existing methods are rarely seen to accomplish such observation. In this study, we investigate the coastal acoustic tomography (CAT) to obtain the long-term horizontal temperature field of an artificial upwelling area in an anechoic tank. We conduct four sets of experiments with different CAT station numbers and compare their data with those collected from temperature sensors. By analyzing the travel time from the CAT experiments, the horizontal temperature field of the upwelling area could be mapped. The CAT results and the comparison results show that the surface temperature of the observed area decreases by approximately 3 °C after upwelling, while the temperature of where the CAT is deployed decreases by about 1 °C; the temperature is lowest at the center of the upwelling area. Increasing the number of stations and station spacing would improve the temperature mapping accuracy. Therefore, the feasibility of using the CAT system to observe artificial upwelling is proved valid. This study indicates the potential application of CAT in temperature field observation in artificial upwelling area in the sea.

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Investigation of long-term drift of NTC temperature sensors with less than 1 mK uncertainty

2015 IEEE 24th International Symposium on Industrial Electronics (ISIE) ◽

10.1109/isie.2015.7281460 ◽

2015 ◽

Cited By ~ 1

Author(s):

Anupama Kulkarni ◽

Mihai Patrascu ◽

Yuri van de Vijver ◽

Jaap van Wensveen ◽

Robert Pijnenburg ◽

...

Keyword(s):

Temperature Sensors

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Evaluation of Leakage Probability of Non-Asbestos Fiber Sheet Gasket at Elevated Temperature Based on Percolation Theory

ASME 2010 Pressure Vessels and Piping Conference: Volume 2 ◽

10.1115/pvp2010-25869 ◽

2010 ◽

Author(s):

Masahiro Hagihara ◽

Hirokazu Tsuji ◽

Atsushi Yamaguchi

Keyword(s):

High Temperature ◽

Percolation Theory ◽

Life Prediction ◽

Prediction Method ◽

Acoustic Tomography ◽

Leakage Path ◽

Temperature Environment ◽

Fiber Sheet ◽

Bolted Flange

A long-term life prediction method for a compressed fiber sheet gasket under a high-temperature environment is studied. Non-asbestos compressed fiber sheet gaskets are now being used as a substitute for asbestos in the bolted flange joint, for instance petrochemical factories. Consequently, there is a real need for a technology to predict the lifetime of non-asbestos compressed fiber sheet gaskets quantitatively. In this report, the facing surface of the gasket and flange is visualized with scanning acoustic tomography (SAT). Voids were observed on the facing surface of the gasket and increased with the increase in exposure time at high temperature. If a leakage path for inner fluids is created by the increasing number of voids, the leak occurs on the facing surface of the gasket. The probability of a leak due to voids and the lifetime of this gasket are predicted by applying the percolation theory, which describes the connectedness of clusters.

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Supplementary material to "Long term O<sub>3</sub>-precursor relationships in Hong Kong: Field observation and model simulation"

10.5194/acp-2017-235-supplement ◽

2017 ◽

Author(s):

Yu Wang ◽

Hao Wang ◽

Hai Guo ◽

Xiaopu Lyu ◽

Hairong Cheng ◽

...

Keyword(s):

Hong Kong ◽

Field Observation ◽

Model Simulation ◽

Supplementary Material

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Validation of the IASI FORLI/Eumetsat ozone products using satellite (GOME-2), ground-based (Brewer-Dobson, SAOZ) and ozonesonde measurements

10.5194/amt-2017-461 ◽

2018 ◽

Cited By ~ 3

Author(s):

Anne Boynard ◽

Daniel Hurtmans ◽

Katerina Garane ◽

Florence Goutail ◽

Juliette Hadji-Lazaro ◽

...

Keyword(s):

A Priori ◽

Long Term Stability ◽

Comparison Results ◽

Independent Observations ◽

Mean Differences ◽

A Priori Uncertainty ◽

The Tropics ◽

Global Mean

Abstract. This paper assesses the quality of IASI/Metop-A (IASI-A) and IASI/Metop-B (IASI-B) ozone (O3) products (total and partial O3 columns) retrieved with the Fast Optimal Retrievals on Layers for IASI Ozone (FORLI-O3) v20151001 software for nine years (2008–2017) through an extensive inter-comparison and validation exercise using independent observations (satellite, ground-based and ozonesonde). IASI-A and IASI-B Total O3 Columns (TOCs) are generally consistent, with a global mean difference less than 0.3 % for both day- and nighttime measurements, IASI-A being slightly higher than IASI-B. A global difference less than 2.4 % is found for the tropospheric (TROPO) O3 column product (IASI-A being lower than IASI-B), which is partly due to a temporary issue related to IASI-A viewing angle in 2015. Our validation shows that IASI-A and IASI-B TOCs are consistent with GOME-2, Dobson, Brewer and SAOZ retrieved ones, with global mean differences in the range 0.1–2 % depending on the instruments. The IASI-A and ground-based TOC comparison for the period 2008–July 2017 shows good long-term stability (negative trends within 3 % decade−1). The comparison results between IASI-A and IASI-B against smoothed ozonesonde partial O3 columns vary in altitude and latitude, with maximum standard deviation for the 300–150 hPa column (20–40 %) due to strong ozone variability and a priori uncertainty. The worst agreement with the ozonesondes and with UV-vis retrieved TOC [satellite and ground] is found at the southern high latitudes. Compared to ozonesonde data, IASI-A and IASI-B O3 products overestimate the O3 abundance in the stratosphere (up to 20 % for the 150–25 hPa column) and underestimates the O3 abundance in the troposphere (within 10 % for the mid-latitudes and ~ 18 % for the tropics). Based on the period 2011–2016, non-significant drift is found for the northern hemispheric tropospheric columns while a small drift prevails for the period before 2011.

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A Method for Reconstruction of Boiler Combustion Temperature Field Based on Acoustic Tomography

Mathematical Problems in Engineering ◽

10.1155/2021/9922698 ◽

2021 ◽

Vol 2021 ◽

pp. 1-11

Author(s):

Yuhui Wu ◽

Xinzhi Zhou ◽

Li Zhao ◽

Chenlong Dong ◽

Hailin Wang

Keyword(s):

Temperature Field ◽

Temperature Distribution ◽

Optimal Parameter ◽

Interpolation Method ◽

Least Square Method ◽

Reconstruction Algorithm ◽

Least Square ◽

Temperature Fields ◽

Acoustic Tomography ◽

Measured Temperature

Acoustic tomography (AT), as a noninvasive temperature measurement method, can achieve temperature field measurement in harsh environments. In order to achieve the measurement of the temperature distribution in the furnace and improve the accuracy of AT reconstruction, a temperature field reconstruction algorithm based on the radial basis function (RBF) interpolation method optimized by the evaluation function (EF-RBFI for short) is proposed. Based on a small amount of temperature data obtained by the least square method (LSM), the RBF is used for interpolation. And, the functional relationship between the parameter of RBF and the root-mean-square (RMS) error of the reconstruction results is established in this paper, which serves as the objective function for the effect evaluation, so as to determine the optimal parameter of RBF. The detailed temperature description of the entire measured temperature field is finally established. Through the reconstruction of three different types of temperature fields provided by Dongfang Boiler Works, the results and error analysis show that the EF-RBFI algorithm can describe the temperature distribution information of the measured combustion area globally and is able to reconstruct the temperature field with high precision.

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Adherence Over Time: The Course of Adherence to Customized Diabetic Insoles as Objectively Assessed by a Temperature Sensor

Journal of Diabetes Science and Technology ◽

10.1177/1932296817747618 ◽

2017 ◽

Vol 12 (3) ◽

pp. 695-700 ◽

Cited By ~ 4

Author(s):

Dominic Ehrmann ◽

Monika Spengler ◽

Michael Jahn ◽

Dea Niebuhr ◽

Thomas Haak ◽

...

Keyword(s):

Diabetic Foot ◽

Temperature Sensor ◽

Small Sample Size ◽

Temperature Sensors ◽

Small Sample ◽

Gender Effects ◽

Kaplan Meier ◽

Foot Problems ◽

Mean Time

Background: Temperature sensors are an objective way to assess adherence to diabetic footwear. Good adherence is essential for the prevention of diabetic foot problems. Little is known about the long-term course of adherence in patients at risk for diabetic foot problems. Method: A temperature sensor was incorporated into the specialized footwear of patients with type 2 diabetes after their first plantar ulceration. Kaplan-Meier curve was used to analyze when patients started to become nonadherent (not wearing the footwear for two straight weeks). Gender effects on adherence were also analyzed. Results: 26 patients with a mean observation time of 133.5 days could be analyzed. Mean wearing time of diabetic footwear was 4.2 ± 3.6 h/day (Mdn = 3.4 h/day; interquartile range = 0.5-7.0 h/day) and on 51% of the days patients did not wear their footwear at all. Kaplan-Meier curve revealed that the mean time of adherence was 27.5 weeks. Men achieved a mean time of adherence of 30.5 weeks, while women only achieved 14 weeks. However, due to the small sample size, this difference was not statistically significant. Conclusions: Temperature sensors revealed a low long-term adherence to diabetic footwear. Women seemed to be at a higher risk for earlier nonadherent behavior. Adherence to diabetic footwear should be closely monitored and tailored intervention strategies should be developed.

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Long-term lateral-torsional buckling behavior of pin-ended CFST arches under uniform radial loads and temperature field

Mechanics of Advanced Materials and Structures ◽

10.1080/15376494.2020.1743397 ◽

2020 ◽

pp. 1-15 ◽

Cited By ~ 1

Author(s):

Yonghui Huang ◽

Zhicheng Yang ◽

Jiyang Fu ◽

Airong Liu

Keyword(s):

Temperature Field ◽

Lateral Torsional Buckling ◽

Torsional Buckling ◽

Buckling Behavior

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Reaction Of The Heat Regime Of Antarctic Ice Sheet Inland Regions On Long-Term Changes Of Climate

Annals of Glaciology ◽

10.1017/s0260305500008879 ◽

1990 ◽

Vol 14 ◽

pp. 329

Author(s):

Vitaly Barbash

Keyword(s):

Temperature Field ◽

Ice Sheet ◽

Heat Regime ◽

Antarctic Ice Sheet ◽

Field Surveys ◽

Climatic Variations ◽

Long Term Changes ◽

The Antarctic ◽

Isotope Analyses

A nonstationary mathematical model of thermics and dynamics of the Antarctic ice sheet has been developed, taking into consideration the influence of long-term changes of climate. The influence of climatic variations during the last 100 000 years on the temperature field within the ice sheet has been analysed. Information about climatic changes is based on paleographic data and isotope analyses of ice samples from bore holes at Vostok and Byrd stations. The input data used include results from field surveys of accumulation, temperatures of upper surface, relief of the base and thickness of the ice sheet along the flowlines in the western and eastern parts of the ice sheet, as well as experimental data on ice rheology. The computations show that traces of the climatic minimum that took place about 18 000 years ago are found in the temperature field of the Antarctic ice sheet. The model developed has proved that warming of climate due to the “greenhouse effect” leads to significant changes in the thermal regime in the upper parts of the ice sheet, but will not lead to conditions threatening bottom layers.

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