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The construction of very good hyperspectral sensors operating in the thermal infrared bands from 8 to 12 microns arouses much interest for the development of data exploitation tools. Temperature emissivity separation (TES) algorithms are very important components of a future toolbox, because they make it possible to extract these two fundamental targets’ parameters. The emissivity relies on the nature of the target's surface materials, while the temperature gives information related to their use and relationship with the environment. The TES technique presented in this paper is based on iteration on temperature principle, where a total square error criterion is used to estimate the temperature. The complete procedure is described in the paper. Its sensitivity to noise is studied and a mathematical behavior model is provided. The model is validated through a Monte-Carlo simulation of the technique's operation.

This work presents a new approach for crowd counting and classification based upon human thermal and motion features. The technique is efficient for automatic crowd density estimation and type of motion determination. Crowd density is measured without any need for camera calibration or assumption of prior knowledge about the input videos. It does not need any human intervention so it can be used successfully in a fully automated crowd control systems. Two new features are introduced for crowd counting purpose: the first represents thermal characteristics of humans and is expressed by the ratio between their temperature and their ambient environment temperature. The second describes humans motion characteristics and is measured by the ratio between humans motion velocity and the ambient environment rigidity. Each ratio should exceed a certain predetermined threshold for human beings. These features have been investigated and proved to give accurate crowd counting performance in real time. Moreover, the two features are combined and used together for crowd classification into one of the three main types, which are: fully mobile, fully static, or mix of both types. Last but not least, the proposed system offers several advantages such as being a privacy preserving crowd counting system, reliable for homogeneous and inhomogeneous crowds, does not depend on a certain direction in motion detection, has no restriction on crowd size. The experimental results demonstrate the effectiveness of the approach.

Although violation of Kirchhoff’s Law of Thermal Radiation has been claimed in a magneto-optic structure, it is shown that Kirchhoff’s Law of Thermal Radiation has not been violated, noting that violation of Kirchhoff’s Law of Thermal Radiation would imply that the Second Law of Thermodynamics has also been violated.

The Mo-, W-incorporated Sm${}_{0.5}$Sr${}_{0.5}$CoO${}_{3-\delta }$ ceramics were prepared by the tape casting and high temperature sintering method. The effects of Mo and W concentration on the structure and optical properties of Sm${}_{0.5}$Sr${}_{0.5}$CoO${}_{3-\delta }$ were investigated in detail. It was found that the Mo-, W-incorporated Sm${}_{0.5}$Sr${}_{0.5}$CoO${}_{3-\delta }$ exhibited extraordinary emittance property in the 3–5$\mu$m and 8–13$\mu$m (especially in the 11–13$\mu$m) wavelength ranges. The results suggest that the novel infrared emittance property of Mo- and W-incorporated Sm${}_{0.5}$Sr${}_{0.5}$CoO${}_{3-\delta }$ could find potential applications in solar thermal or radiative cooling systems.

Vascular complications are responsible for most of the morbidity and mortality in diabetic patients. Effective strategies to improve circulation appear to be another important issue in addition to the interventions of blood glucose control. Previous studies have shown that the biological effects on humans after using the materials containing ceramic particles emits far infrared radiation (FIR). The present study is to investigate the warming effect of the fabrics containing specified metals in diabetic patients. A total of 28 diabetic patients were blinded and randomly assigned to treatment group ($N=18$) and control group ($N=10$), respectively. The subjects of treatment group were ministered with the blankets with fibers containing the specified metals, while the subjects of control group were provided with blankets of ordinary material. The skin temperature and microcirculatory perfusion were monitored before and after 20-min use of the blankets at shoulder and bilateral calves. After warming with blankets, the treatment group revealed a higher increased ratio of skin perfusion than control ($p<0.05$), while there was no prominent variation on the wavelet spectrum of the perfusion signal. Although it is already a known fact that passive FIR warming has the advantages of safety and convenience, our results suggest that warming by wearing the textiles containing the specified metals with high FIR emissivity is a solution for daily skin care of diabetic patients.

Amorphous and crystalline tungsten trioxide (WO₃) electrochromic films of 240 to 400 nm thick were grown on single crystal silicon wafer and ITO-coated glass substrates by reactive sputtering from a tungsten target. The electrochemical properties of the films were characterized by cyclic voltammetry between −1.0 ~ +1.0 V in 1M LiClO₄/PC solutions. The Cary 500 measurements of the films indicated remarkable changes in the transmission and reflection in visible and infrared regions due to Li⁺ ions injection/extraction. The emissivity of the WO₃ films on the Au substrates was modulated in the range from 0.042 to 0.450. The results showed that the crystalline WO₃, films obtained here have excellent thermal emissivity modulation, enabling fabrication of electrochromic devices that can freely change their optical properties under a slight voltage pulse.

The construction of very good hyperspectral sensors operating in the thermal infrared bands from 8 to 12 microns arouses much interest for the development of data exploitation tools. Temperature emissivity separation (TES) algorithms are very important components of a future toolbox, because they make it possible to extract these two fundamental targets' parameters. The emissivity relies on the nature of the target's surface materials, while the temperature gives information related to their use and relationship with the environment. The TES technique presented in this paper is based on iteration on temperature principle, where a total square error criterion is used to estimate the temperature. The complete procedure is described in the paper. Its sensitivity to noise is studied and a mathematical behavior model is provided. The model is validated through a Monte-Carlo simulation of the technique's operation.