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Using our new program code, we have calculated the temperature dependence of the Seebeck coefficient ( S - T ) in the linearized Boltzmann transport equation with a constant relaxation time (LBT-CRT) for Fe2VAl (cF16) and its quaternary compounds for the range from − 263 °C (10 K) to 727 °C (1000 K). We revealed that Fe2VAl compound free from any defects exhibited the Seebeck coefficient with a negative sign at odds with experimental data with a positive sign. However, this dilemma could be removed after the introduction of Al/V near neighbor inversion defects into the perfect Fe2VAl. A key point in developing a reliable temperature-dependent Seebeck coefficient software lies in how precisely we calculate the density of states times square of the group velocity v x 2 along the direction x of thermal gradient. The present method is contrasted to the Fourier Transform Interpolation method in BoltzTraP developed by Madsen and Singh (2006). Nevertheless, both could reproduce the experimental data of Fe2VAl once the inversion effect was taken into account. Our new software allows us to seek the origin of characteristic behaviors in the S - T curve by decomposing the electronic parameter above into sub-bands and analyzing the sub-band dependence of the energy spectrum A ε in the LBT-CRT equation. [ABSTRACT FROM AUTHOR]

We have investigated the electronic structure of a potential thermoelectric material, higher manganese silicide, and its solid solutions with supersaturated Re by means of hard x-ray photoemission spectroscopy. The unusual Re substitution dependence of thermoelectric properties in the higher manganese silicide, reducing the electrical resistivity without altering the Seebeck coefficient, can be explained in terms of the variation of the density of states at the Fermi level and its energy derivative. Such an electronic structure variation contributes to an improvement in the thermoelectric performance in combination with the suppressed thermal conductivity. [ABSTRACT FROM AUTHOR]

Detailed demographics play an important role in the development of smart cities. However, especially in developing countries, the maintenance and management of this data is incomplete, which hinders the promotion of smart cities. The objective of this study is to develop a method to create detailed building distribution maps from satellite images, which will serve as a basis for developing detailed demographic data to support the promotion of smart cities around the world. The target area is several areas of Tokyo where validation data is available. We first developed a method for extracting buildings from satellite images and then estimating the building use to determine the buildings where residents are distributed. Both methods use deep learning. As a result, it was possible to extract buildings with an extraction rate (the number of buildings in the automatically extracted building data divided by the number of buildings in the data for verification) of up to 60.3% for the entire target area. In addition, in the estimation of building use, our method was able to classify detached and non-detached buildings with an average accuracy of 78.7% for the entire target area. [ABSTRACT FROM AUTHOR]

Heusler-type Fe2VAl thermoelectric materials have been processed by high-pressure torsion (HPT) to improve their thermoelectric performance through a drastic reduction of the thermal conductivity. While the thermal conductivity for Fe2VTa0.05Al0.95 is about 10 W/m K at 300 K, it is reduced to about 5.0 W/m K due to HPT processing. Furthermore, even after annealing at 873 K for recurrence of the Heusler-type structure, Ta-doped Fe2VTa0.05Al0.95 possesses an ultra-fine grained structure with an average grain size of about 80 nm, in contrast to the presence of large grains of about 270 nm for non-doped Fe2V1.05Al0.95. Since scanning transmission electron microscopy combined with energy-dispersive X-ray analysis reveals the solute segregation of Ta along grain boundaries and recrystallization interfaces, the retardation of recrystallization could be caused by the solute drag effect, leading to a suppression of grain coarsening. Thus, it is possible to retain the low thermal conductivity of about 5.0 W/m K at 300 K for Fe2VTa0.05Al0.95, in parallel with the restoration of a large power factor, so that the dimensionless figure of merit reaches ZT = 0.30 at around 500 K. [ABSTRACT FROM AUTHOR]

A 1T cryocooler-cooled oxide superconducting pulsed coil, which is a 16 layer solenoidal coil wound with an interlayer-transposed 4-strand parallel conductor composed of Bi2223 multifilamentary flat wires is fabricated. The thermal properties of the cryocooler-cooled oxide superinducting pulsed coil is described, taking into account the heat generation of ac loss and flux-flow loss and the cooling capacity of a cryocooler Ac loss and the cooling capacity of the cryocooler have been studied.

This article compares the outcomes of two minimally invasive treatments, endoscopic dissection (ESD) and transoral videolaryngoscopic surgery (TOVS), for superficial pharyngeal tumors. The study reviewed 47 cases treated with either ESD or TOVS from 2013 to 2022. The results showed that ESD had a higher R0 resection rate and fewer recurrences compared to TOVS. The authors suggest that ESD's reliable range diagnosis using endoscopic magnification and image enhancement may contribute to its higher success rate. [Extracted from the article]

This article discusses the efficacy of gel immersion endoscopic submucosal dissection (GI-ESD) for superficial non-ampullary duodenal epithelial tumors (SNADETs) larger than 20 mm. The study compares the short-term outcomes of GI-ESD and conventional ESD for SNADETs. The results show that GI-ESD improves endoscopic maneuverability, provides a good field of view, and reduces damage to the muscle layer. It suggests that GI-ESD may be a safer option for the resection of SNADETs. [Extracted from the article]

This article discusses a study that aimed to determine whether image-enhanced endoscopies (IEEs) improve the visibility of superficial non-ampullary duodenal epithelial tumors (SNADETs) compared to white light imaging (WLI). The study analyzed 50 lesions and found that texture and color enhancement imaging (TXI) improved SNADET visibility compared to WLI, particularly during underwater observation. The findings suggest that TXI may be useful for the detection and assessment of the lateral extent of SNADETs. [Extracted from the article]

Four-dimensional (4-D) computed tomography (CT) is a dynamic volume imaging system of moving organs with an image quality comparable to conventional CT and it is realized by continuous and high-speed cone-beam CT. We have developed a novel two-dimensional (2-D) detector for 4-D CT, which is based on the present CT technology, and mounted it on the gantry frame of the state-of-the-art CT-scanner. In the present paper, we describe the design and the performance evaluation results of the first model of the 4-D CT-scanner. The X-ray detector for the 4-D CT-scanner is a discrete pixel detector in which pixel data are measured from independent detector elements. The numbers of elements are 912 (channels) x 256 (segments) and the element size is approximately 1 mm x 1 mm. Data sampling rate is 900 views (frames)/s and the dynamic range of the A/D converter is 16 bits. The rotation speed of the gantry is 1.0 s/rotation. The data transfer system between rotating and stationary parts in the gantry consists of laser diode and photodiode pairs and it achieves a net transfer speed of 5 Gbps. Volume data of 512 x 512 x 256 voxels are reconstructed with an Feldkamp-Davis-Kress (FDK) algorithm by parallel use of microprocessors. The image characteristics such as noise, uniformity, and spatial resolution were evaluated with stationary phantoms in a single rotation. Exposure dose to an object was measured with an extension of the standard measurement method of CT dose index (CTDI). Several volunteers were scanned to explore clinical potentials. For the 4-D CT-scanner, the image characteristics of stationary objects were almost the same as that of conventional CT, while CTDI of the 4-D CT was slightly higher than that of conventional CT. Isotropic resolving power of less than 0.5 mm was achieved for the stationary object. Index Terms--Dynamic volume imaging, four-dimensional computed tomography (4-D CT), phantom study.

Development and testing of a cryocooler-cooled superconducting pulse coil is described and discussed.

Venous diseases like iliofemoral deep vein thrombosis and valvular dysfunction induce venous hypertension. To know the effects of the hypertension on venous mechanics, blood pressure in the left femoral vein in the rabbit was chronically elevated by the constriction of the left external iliac vein. Wall dimensions and biomechanical properties of the femoral vein were studied in vitro at 1, 2, or 4 wk after surgery. Blood pressure measured immediately before the animal was killed was significantly higher in the left femoral vein than in the sham-operated, contralateral vein. Wall thickness was increased by blood pressure elevation even at I wk, which restored circumferential wall stress to a control level. The stress was kept at normal up to 4 wk. Vascular tone and vascular contractility were increased by the elevation of blood pressure; however, wall elasticity and compliance were kept at a normal level. These results are very similar to those observed in hypertensive arteries, indicating that not only arteries but veins optimally operate against blood pressure elevation. hypertrophy; remodeling; wall stress