scholarly journals Thermal consequences of colour and near-infrared reflectance

2017 ◽  
Vol 372 (1724) ◽  
pp. 20160345 ◽  
Author(s):  
Devi Stuart-Fox ◽  
Elizabeth Newton ◽  
Susana Clusella-Trullas

The importance of colour for temperature regulation in animals remains controversial. Colour can affect an animal's temperature because all else being equal, dark surfaces absorb more solar energy than do light surfaces, and that energy is converted into heat. However, in reality, the relationship between colour and thermoregulation is complex and varied because it depends on environmental conditions and the physical properties, behaviour and physiology of the animal. Furthermore, the thermal effects of colour depend as much on absorptance of near-infrared ((NIR), 700–2500 nm) as visible (300–700 nm) wavelengths of direct sunlight; yet the NIR is very rarely considered or measured. The few available data on NIR reflectance in animals indicate that the visible reflectance is often a poor predictor of NIR reflectance. Adaptive variation in animal coloration (visible reflectance) reflects a compromise between multiple competing functions such as camouflage, signalling and thermoregulation. By contrast, adaptive variation in NIR reflectance should primarily reflect thermoregulatory requirements because animal visual systems are generally insensitive to NIR wavelengths. Here, we assess evidence and identify key research questions regarding the thermoregulatory function of animal coloration, and specifically consider evidence for adaptive variation in NIR reflectance. This article is part of the themed issue ‘Animal coloration: production, perception, function and application’.

1995 ◽  
Vol 49 (6) ◽  
pp. 765-772 ◽  
Author(s):  
M. S. Dhanoa ◽  
S. J. Lister ◽  
R. J. Barnes

Scale differences of individual near-infrared spectra are identified when set-independent standard normal variate (SNV) and de-trend (DT) transformations are applied in either SNV followed by DT or DT then SNV order. The relationship of set-dependent multiplicative scatter correction (MSC) to SNV is also referred to. A simple correction factor is proposed to convert derived spectra from one order to the other. It is suggested that the suitable order for the study of changes using difference spectra (when removing baselines) should be DT followed by SNV, which leads to all derived spectra on the scale of mean zero and variance equal to one. If baselines are identical, then SNV scale spectra can be used to calculate differences.


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3952
Author(s):  
Piotr Sobik ◽  
Olgierd Jeremiasz ◽  
Paweł Nowak ◽  
Agata Sala ◽  
Bartłomiej Pawłowski ◽  
...  

Cuprorivaite, also known as Egyptian blue (EB), CaCuSi4O10, has been utilized as an important blue pigment for thousands of years. It shows a 430–800 nm broad excitation band and an intense 910–920 nm near-infrared (NIR) emission peak at room temperature. The application that motivates the current research is for luminescent solar concentrator (LSC) usage. Current technology for this purpose relies on high near-infrared reflectance. This article addresses the investigation of the relationship between dispersing methods and photoluminescence (PL) intensity. Mechanical grinding methods investigated in the study were: horizontal bead mill, exfoliation and three-roll mill. The initial aim of the study was to verify if the proposed methods do not damage PL. To the surprise of the authors, three-roll mill treatment enhanced PL by nearly 50% without altering the morphology of the powder. An X-ray diffraction study suggested slight alterations in the crystal lattice.


2021 ◽  
Author(s):  
Gen Ito ◽  
Jessica Flahaut ◽  
Jun Huang

<p>The far side of the Moon, which has generally been less frequently targeted by robotic and human missions in the past, has become more available for compositional analyses with measurements made by the Chang’E-4 mission that landed in South Pole-Aitken Basin in 2019. The rover of the mission, Yutu-2, has traversed over 500 m now and acquired more than 100 measurements of visible and near-infrared (VNIR) reflectance spectra. In this study, we analyze the full set of VNIR reflectance spectra collected so far in order to better understand the geology of the Von Karman mare. We compute spectral parameters to quantize major features of spectra and infer mineralogy, e.g., pyroxene composition analysis using the relationship between spectral band depths at 1 µm and 2 µm. Many of Chang’E-4 spectra do not have a detectable spectral band at 2 µm in which case we use spectral parameters for the band at 1 µm to make classifications and infer the presence of other minerals. Pyroxene composition inferred from Chang’E-4 spectra are midway between orthopyroxene and clinopyroxene, showing noticeably unique grouping when compared with 1 µm and 2 µm band depth data available from past studies. For spectra without detectable band at 2 µm, initial classification efforts based solely on spectral parameters of the 1 µm band seem to indicate that at least two distinct groups exist. We are further investigating these preliminary findings, such as through comparisons to data from Moon Mineralogy Mapper, to better understand the mineralogy of the measured materials and the geology of the region explored by Yutu-2 rover. </p>


1996 ◽  
Vol 1996 ◽  
pp. 226-226
Author(s):  
S.J. Lister ◽  
M.S. Dhanoa ◽  
J.L. Stewart ◽  
M. Gill

The chemical composition of tropical forages is generally more complex than that of temperate forages, yet the need for simple methods to predict nutritive value is greater. Near Infrared Reflectance (NIR) spectra could provide a possible solution. NIR has been used to predict both in vitro and in vivo digestibility (Murray, 1993). Direct calibration with in vivo parameters is ideal, but factors such as different types of forages, animals and management conditions have to be taken into consideration. The gas production technique, which may be considered as an in vitro counterpart of the dacron bag technique, provides information relating to the fermentable fractions and kinetics of a forage and these parameters can be related to the NIR spectra. The aim of this study was to investigate the relationship between NIR spectra and cumulative gas production and derived parameters in tree leaves.


1996 ◽  
Vol 1996 ◽  
pp. 226-226
Author(s):  
S.J. Lister ◽  
M.S. Dhanoa ◽  
J.L. Stewart ◽  
M. Gill

The chemical composition of tropical forages is generally more complex than that of temperate forages, yet the need for simple methods to predict nutritive value is greater. Near Infrared Reflectance (NIR) spectra could provide a possible solution. NIR has been used to predict both in vitro and in vivo digestibility (Murray, 1993). Direct calibration with in vivo parameters is ideal, but factors such as different types of forages, animals and management conditions have to be taken into consideration. The gas production technique, which may be considered as an in vitro counterpart of the dacron bag technique, provides information relating to the fermentable fractions and kinetics of a forage and these parameters can be related to the NIR spectra. The aim of this study was to investigate the relationship between NIR spectra and cumulative gas production and derived parameters in tree leaves.


2013 ◽  
Vol 12 (4) ◽  
pp. 157-169 ◽  
Author(s):  
Philip L. Roth ◽  
Allen I. Huffcutt

The topic of what interviews measure has received a great deal of attention over the years. One line of research has investigated the relationship between interviews and the construct of cognitive ability. A previous meta-analysis reported an overall corrected correlation of .40 ( Huffcutt, Roth, & McDaniel, 1996 ). A more recent meta-analysis reported a noticeably lower corrected correlation of .27 ( Berry, Sackett, & Landers, 2007 ). After reviewing both meta-analyses, it appears that the two studies posed different research questions. Further, there were a number of coding judgments in Berry et al. that merit review, and there was no moderator analysis for educational versus employment interviews. As a result, we reanalyzed the work by Berry et al. and found a corrected correlation of .42 for employment interviews (.15 higher than Berry et al., a 56% increase). Further, educational interviews were associated with a corrected correlation of .21, supporting their influence as a moderator. We suggest a better estimate of the correlation between employment interviews and cognitive ability is .42, and this takes us “back to the future” in that the better overall estimate of the employment interviews – cognitive ability relationship is roughly .40. This difference has implications for what is being measured by interviews and their incremental validity.


2018 ◽  
Vol 13 (Number 2) ◽  
pp. 67-77
Author(s):  
Anis Syamimi Abd Rahim ◽  
Mohd Norhasni Mohd Asaad

The purpose of this study is to review the implementation of ISO 9001:2015 in order to improve the quality of services at Pusat Kesihatan Universiti (PKU), Universiti Utara Malaysia. The respondents of this study were customers at the PKU, UUM. The questionnaire was distributed to 50 respondents. The data were analyzed using SPSS software version 24. The data were tested using descriptive statistics, and correlation analysis to answer the research questions and to achieve the objectives. The findings show that customers agree that implementation of ISO 9001:2015 give service at PKU, UUM is good and satisfied. Through the correlation test, the results showed that the relationship between the implementation of ISO 9001:2015 has a positive and significant impact on customer satisfaction and the effect of implementing ISO 9001:2015 has a positive and significant impact in improving quality of service at PKU, UUM.Through mean and standard deviation tests, results show that tangible dimensions are the main dimensions of customer satisfaction while dimensions with low values are dimensions of responsiveness.Therefore, all aspects of service in PKU, UUM will be strengthened and all aspects of the weaknesses could be addressed to improve the service in order to maintain good quality services.


2016 ◽  
Vol 2 (1) ◽  
pp. 1
Author(s):  
Noorlaila Yunus ◽  
Cairul Azwa Azimi

Organizational Citizenship Behaviour (OCB) has been widely studied across the boarders especially in the western countries. This workplace voluntary behaviour is associated with many predictors that may bring whether major, minor or negative influence towards the engagement of employees’ OCB. Basically, this study is focusing on motivation as the predictor or independent variable that influence employees’ engagement on the OCB (altruism, conscientiousness, courtesy, civic virtue and sportsmanship) behaviour. Herzberg’s motivator factor (achievement, advancement, recognition and growth) has been chosen as the independent variable. A total of 150 questionnaires were distributed conveniently to respondents. With 125 questionnaires returned, researcher was able to analyze the data based on the research questions and hypotheses developed. The findings showed moderate and weak, significant relationship between the variable excluding the relationship between independent variable and civic virtue and sportsmanship. Thus, Herzberg’s motivator factor was not a predictor to civic virtue and sportsmanship behaviour. However for the strongest predictor; achievement, growth and growth are strongly predicts the altruism, conscientiousness and courtesy behaviour respectively. However, with the absence of relationship between independent variable and civic virtue as well as sportsmanship, therefore the strongest predictor cannot be determined as the value recorded was below the criterion.


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