scholarly journals Thermal imaging as a viable tool for monitoring plant stress

OENO One ◽  
2007 ◽  
Vol 41 (2) ◽  
pp. 77 ◽  
Author(s):  
Manfred Stoll ◽  
Hamlyn G. Jones
Keyword(s):  
Infrared Thermography ◽  
Thermal Imaging ◽  
Plant Stress ◽  
Leaf Temperature ◽  
Thermal Imager ◽  
First Line ◽  
Frequency Distributions ◽  
Long Wave ◽  
Thermal Data ◽  
Thermal Imagers

<p style="text-align: justify;"><strong>Aims</strong>: The objective of this paper was to describe an approach to the use of thermal data for shaded leaves rather than areas fully exposed to the sun. Secondly to make use of infrared thermography as a powerful tool to measure effects of solar radiation on berry temperature.</p><p style="text-align: justify;"><strong>Methods and results</strong>: Thermal images were obtained with a long-wave thermal imager. There is often less variability within an image for a shaded portion of the canopy than for a sunlit canopy. The temperature frequency distributions of sunlit leaves displayed a far wider range of temperature variation compared to shaded leaves.</p><p style="text-align: justify;"><strong>Conclusion</strong>: With thermal imagers it is feasible to select precisely the leaves for investigation. The remote sensing approach using infrared thermography combined with techniques available for image analysis open up a number of opportunities for comparative studies such as screening activities.</p><p style="text-align: justify;"><strong>Significance and impact of study</strong>: Infrared thermography can be implemented as a first line of detection to determine the onset of plant stress due to changes in stomatal aperture. This approach can give reliable and sensitive indications of leaf temperature and hence to calculate stomatal conductance.</p>

Estimation of Effect of Emissivity on Target Detection through Thermal Imaging Systems

2017 ◽  
Vol 67 (2) ◽  
pp. 177 ◽  
Author(s):  
Amit Kumar Sharma ◽  
Sanjay Kumar Sharma ◽  
Prashant Vasistha ◽  
Jagdish Prasad Mangalhara
Keyword(s):  
Thermal Imaging ◽  
Background Radiation ◽  
Thermodynamic Temperature ◽  
Night Vision ◽  
Thermal Imager ◽  
Thermal Contrast ◽  
Detection Range ◽  
Thermal Imagers ◽  
Long Wave Infrared ◽  
Ir Bands

<p>The effects of target emissivity on apparent thermal contrast as well as on detection range capabilities of thermal imagers in long wave infrared and middle wave infrared bands were evaluated. The apparent thermal contrast (to be seen by the thermal imager at standoff distance), considering only the emission from target and background, was first computed in both the IR bands in terms of target emissivity and secondly the apparent thermal contrast, considering the background radiation reflected off the target, was also computed. A graphical user interface simulation in MATLAB was prepared for the estimation of total apparent thermal contrast taking into account both the emission and reflection. This total apparent thermal contrast was finally used in night vision thermal and image processing model for predicting the detection range performance of thermal imagers. Results of the analysis show that the effect of target emissivity on thermal contrast estimates is more pronounced in LWIR. The lower thermodynamic temperature difference between target and background at lower values of target emissivity leads to negative thermal contrast which in-turn leads to higher detection ranges.</p>

scholarly journals TECHNICAL MEANS OF AIRINTELLIGENCE TO ENSURE THE PHYSICAL SECURITY OF INFORMATION ACTIVITIES

2021 ◽  
Vol 12 (4) ◽  
pp. 143-150
Author(s):  
Artem Platonenko ◽  
Volodymyr Sokolov ◽  
Pavlo Skladannyi ◽  
Heorhii Oleksiienko
Keyword(s):  
Thermal Imaging ◽  
Critical Infrastructure ◽  
Weather Conditions ◽  
Unmanned Vehicles ◽  
License Plate ◽  
Thermal Imager ◽  
Camera Model ◽  
Thermal Imagers ◽  
Private And Public

This article is devoted to highlighting the real practical capabilities of UAV thermal imaging cameras, which allow you to effectively and safely identify potentially dangerous objects that may threaten the object of information activities, or the safety of citizens or critical infrastructure of Ukraine. Based on many years of flight experience and training of specialists for private and public institutions, it was decided to compare the quality characteristics and capabilities of detection, recognition and identification of objects using modern unmanned vehicles. To ensure public safety and control of the territory, there are models with multiple optical zoom, which from a distance of 500 m allow to recognize the license plate of the car, or versions with thermal imager, which in night can help see the car, the temperature difference against other cars, and the fact that a person comes out of it. Test flights were performed at altitudes from 15 to 100 m, in the open, without the presence of bushes, trees or obstacles. Depending on the camera model and weather conditions, the figures obtained may differ significantly. The main advantages and differences in the quality of thermal imaging cameras for UAVs are described. The quality of the obtained image is demonstrated on real examples and under the same conditions. A number of requirements have been developed for shooting a quadcopter with thermal imagers of objects such as a car and a person from different heights, according to Johnson's criteria, and a work plan has been developed for further research to prepare and provide effective recommendations for pilots using this technique territories of objects of information activity and during performance of service in air reconnaissance units of law enforcement agencies of Ukraine.

Evaluation of Package Defects by Thermal Imaging Techniques

2002 ◽  
Author(s):  
Yongmei Liu ◽  
Rajen Dias
Keyword(s):  
Infrared Thermography ◽  
Thermal Imaging ◽  
High Speed ◽  
Imaging Techniques ◽  
Thermal Response ◽  
Analysis Tool ◽  
Nondestructive Analysis ◽  
Ir Camera ◽  
External Heating

Abstract Study presented here has shown that Infrared thermography has the potential to be a nondestructive analysis tool for evaluating package sublayer defects. Thermal imaging is achieved by applying pulsed external heating to the package surface and monitoring the surface thermal response as a function of time with a high-speed IR camera. Since the thermal response of the surface is affected by the defects such as voids and delamination below the package surface, the technique can be used to assist package defects detection and analysis.

scholarly journals PSV-16 Infrared thermography technology as a promising tool for assessing temperament of water buffaloes

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 220-221
Author(s):  
Caroline L Francisco ◽  
André M Castilhos ◽  
Daiane C Marques da Silva ◽  
Fabiola Martinez da Silva ◽  
Aline S Aranha ◽  
...  
Keyword(s):  
Infrared Thermography ◽  
Fixed Effects ◽  
Thermal Imager ◽  
Initial Body Weight ◽  
Water Buffaloes ◽  
Promising Tool ◽  
Genetic Groups ◽  
Body Regions ◽  
The Mean ◽  
Positive Correlations

Abstract This study evaluated the use of the infrared thermography (IT) as a tool to identify the temperament of 75 non-castrated water buffaloes (390±32 days of age; 310±61.27 kg of initial body weight) of 3 genetic groups (GG:Jafarabadi, Mediterranean, and Murrah; n = 25 for each GG). The animals were classified for temperament through the temperament score (TSc) obtained by the mean of the sum of the scores of the time of entry into the squeeze chute (1 to 5: 1=greater time spent for entry; 5=less time spent for entry) and the exit velocity score (1 to 5: 1=lower speed; 5=higher speed) calculated after the period of adaptation to the feedlot (d0). The animals were categorized into adequate (ADQ; TSc≤3) or excitable (EXC; TSc &gt;3) temperaments. The rectal temperature was measured and IT images were obtained (Testo 882 Thermal Imager, Testo, Inc, Germany) from regions of the chest, eye, snout, cheek, foreleg (left side), ribs, hind legs, rear area (left side), and scrotum on d0. Data were analyzed using MIXED procedure in SAS, considering the GG, temperament, and the resulting interaction as fixed effects. Correlation was analyzed using the CORR procedure of SAS. There were no effects of interactions (P ≥ 0.14). ADQ animals showed lower rectal (P = 0.02) and ribs (P = 0.05) temperatures than EXC animals (Table1). Tendencies for temperament effect were detected for chest (P = 0.06) and rear area (P = 0.07). There was no effect of temperament for other variables (P = 0.19). Positive correlations were verified between the TSc and rectal (r=0.36; P &lt; 0.01), chest (r=0.35; P &lt; 0.01), and rear area (r=0.33; P &lt; 0.01) temperatures. Tendency for a positive correlation was detected between TSc and scrotum (r=0.23; P = 0.07). In conclusion, the temperament causes changes in the temperature of some body regions suggesting the IT technology may be a promising tool for assessing the temperament of water buffaloes. Supported by FAPESP (#2018/25939-1; #2014/05473-7).

scholarly journals Infrared Thermography Measurement for Vibration-Based Structural Health Monitoring in Low-Visibility Harsh Environments

Sensors ◽  
2020 ◽  
Vol 20 (24) ◽  
pp. 7067
Author(s):  
Jia-Hao He ◽  
Ding-Peng Liu ◽  
Cheng-Hsien Chung ◽  
Hsin-Haou Huang
Keyword(s):  
Structural Health Monitoring ◽  
Infrared Thermography ◽  
Mode Shape ◽  
Health Monitoring ◽  
Large Scale ◽  
Frame Structure ◽  
Harsh Environments ◽  
Thermal Imager ◽  
Heat Sources ◽  
Structural Health

In this study, infrared thermography is used for vibration-based structural health monitoring (SHM). Heat sources are employed as sensors. An acrylic frame structure was experimentally investigated using the heat sources as structural marker points to record the vibration response. The effectiveness of the infrared thermography measurement system was verified by comparing the results obtained using an infrared thermal imager with those obtained using accelerometers. The average error in natural frequency was between only 0.64% and 3.84%. To guarantee the applicability of the system, this study employed the mode shape curvature method to locate damage on a structure under harsh environments, for instance, in dark, hindered, and hazy conditions. Moreover, we propose the mode shape recombination method (MSRM) to realize large-scale structural measurement. The partial mode shapes of the 3D frame structure are combined using the MSRM to obtain the entire mode shape with a satisfactory model assurance criterion. Experimental results confirmed the feasibility of using heat sources as sensors and indicated that the proposed methods are suitable for overcoming the numerous inherent limitations associated with SHM in harsh or remote environments as well as the limitations associated with the SHM of large-scale structures.

CLASSIFICATION OF HUMAN FACIAL AND AURAL TEMPERATURE USING NEURAL NETWORKS AND IR FEVER SCANNER: A RESPONSIBLE SECOND LOOK

2005 ◽  
Vol 05 (01) ◽  
pp. 165-190 ◽  
Author(s):  
E. Y. K. NG ◽  
COLIN CHONG ◽  
G. J. L. KAW
Keyword(s):  
Neural Network ◽  
Body Temperature ◽  
False Negative ◽  
The Body ◽  
Body Core Temperature ◽  
Thermal Imager ◽  
Facial Skin ◽  
Thermal Imagers ◽  
Cardinal Symptom ◽  
Elevated Body Temperature

Severe Acute Respiratory Syndrome (SARS) is a highly infectious disease caused by a coronavirus. Screening to detect potential SARS infected subject with elevated body temperature plays an important role in preventing the spread of SARS. The use of infrared (IR) thermal imaging cameras has thus been proposed as a non-invasive, speedy, cost-effective and fairly accurate means for mass blind screening of potential SARS infected persons. Infrared thermography provides a digital image showing temperature patterns. This has been previously utilized in the detection of inflammation and nerve dysfunctions. It is believed that IR cameras may potentially be used to detect subjects with fever, the cardinal symptom of SARS and avian influenza. The accuracy of the infrared system can, however, be affected by human, environmental, and equipment variables. It is also limited by the fact that the thermal imager measures the skin temperature and not the body core temperature. Thus, the use of IR thermal systems at various checkpoints for mass screening of febrile persons is scientifically unjustified such as what is the false negative rate and most importantly not to create false sense of security. This paper aims to study the effectiveness of infrared systems for its application in mass blind screening to detect subjects with elevated body temperature. For this application, it is critical for thermal imagers to be able to identify febrile from normal subjects accurately. Minimizing the number of false positive and false negative cases improves the efficiency of the screening stations. False negative results should be avoided at all costs, as letting a SARS infected person through the screening process may result in potentially catastrophic results. Hitherto, there is lack of empirical data in correlating facial skin with body temperature. The current work evaluates the correlations (and classification) between the facial skin temperatures to the aural temperature using the artificial neural network approach to confirm the suitability of the thermal imagers for human temperature screening. We show that the Train Back Propagation and Kohonen self-organizing map (SOM) can form an opinion about the type of network that is better to complement thermogram technology in fever diagnosis to drive a better parameters for reducing the size of the neural network classifier while maintaining good classification accuracy.

Relative Temperature Maximum in Wound Infection and Inflammation as Compared with a Control Subject Using Long-Wave Infrared Thermography

2017 ◽  
Vol 30 (9) ◽  
pp. 406-414 ◽  
Author(s):  
Arjun Chanmugam ◽  
Diane Langemo ◽  
Korissa Thomason ◽  
Jaimee Haan ◽  
Elizabeth A. Altenburger ◽  
...  
Keyword(s):  
Wound Infection ◽  
Control Subject ◽  
Infrared Thermography ◽  
Relative Temperature ◽  
Long Wave ◽  
Infection And Inflammation ◽  
Long Wave Infrared

The hyperspectral thermal imager: High spectral and spatial resolution thermal imaging from a 6U platform

2021 ◽  
Author(s):  
Robert Wright ◽  
Paul Lucey ◽  
Miguel Nunes ◽  
Sarath Gunapala ◽  
Sir Rafol ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Thermal Imaging ◽  
Thermal Imager

scholarly journals Applications of UAV Thermal Imagery in Precision Agriculture: State of the Art and Future Research Outlook

2020 ◽  
Vol 12 (9) ◽  
pp. 1491 ◽  
Author(s):  
Gaetano Messina ◽  
Giuseppe Modica
Keyword(s):  
Precision Agriculture ◽  
State Of The Art ◽  
Plant Stress ◽  
Stress Conditions ◽  
Plant Diseases ◽  
Basic Knowledge ◽  
Plant Phenotyping ◽  
Future Research ◽  
Thermal Data ◽  
Low Altitude

Low-altitude remote sensing (RS) using unmanned aerial vehicles (UAVs) is a powerful tool in precision agriculture (PA). In that context, thermal RS has many potential uses. The surface temperature of plants changes rapidly under stress conditions, which makes thermal RS a useful tool for real-time detection of plant stress conditions. Current applications of UAV thermal RS include monitoring plant water stress, detecting plant diseases, assessing crop yield estimation, and plant phenotyping. However, the correct use and interpretation of thermal data are based on basic knowledge of the nature of thermal radiation. Therefore, aspects that are related to calibration and ground data collection, in which the use of reference panels is highly recommended, as well as data processing, must be carefully considered. This paper aims to review the state of the art of UAV thermal RS in agriculture, outlining an overview of the latest applications and providing a future research outlook.

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