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It is very important to design electrical machineries with high efficiency from the point of view of saving energy. Therefore, topology optimization (TO) is occasionally used as a design method for improving the performance of electrical machinery under the reasonable constraints. Because TO can achieve a design with much higher degree of freedom in terms of structure, there is a possibility for deriving the novel structure which would be quite different from the conventional structure. In this paper, topology optimization using sequential linear programming using move limit based on adaptive relaxation is applied to two models. The magnetic shielding, in which there are many local minima, is firstly employed as firstly benchmarking for the performance evaluation among several mathematical programming methods. Secondly, induction heating model is defined in 2-D axisymmetric field. In this model, the magnetic energy stored in the magnetic body is maximized under the constraint on the volume of magnetic body. Furthermore, the influence of the location of the design domain on the solutions is investigated.

Abstract Background Buried penis, most commonly seen in children, is particularly debilitating in adults, resulting in inability to void while standing and it also affects vaginal penetration. We report a case of buried penis due to a traffic accident, which caused dislocation of the fractured pubic bone that shifted inside and pulled the penis by its suspensory ligament. Case presentation A 55-year-old man was admitted to our hospital with a chief complaint of hidden penis while in the sitting position. He had suffered a pelvic fracture in a traffic accident four years previously, and his penis was covered with suprapubic fat when he was in a sitting position. He was unable to have sexual intercourse. We performed a penile lengthening procedure, including inverse V-Y-plasty of the dorsal skin of the penile root, suspensory desmotomy and fat removal, under general anesthesia. There was a good cosmetic result with satisfactory penile erection, which allowed successful sexual intercourse after surgery. Conculsion We performed penile elongation surgery with inverse V-Y-plasty of the dorsal skin of the penile root, suspensory desmotomy, and fat removal. Surgical treatment of buried penis achieves marked aesthetic and functional improvement, and benefits the majority of patients, resulting in satisfactory erection and successful sexual intercourse.

Abstract Background Wilms' tumor is rarely found in adults and there are no established treatment guidelines for such tumors in adults. Whereas calcification is a common finding in neuroblastoma, it is considered uncommon in Wilms' tumor. Case presentation We report a case of adult Wilms' tumor with calcification in a 22-year-old man. He had been initially referred to our hospital with a chief complaint of right flank pain 5 years previously, when abdominal computed tomography had revealed focal calcification at the upper pole of the right kidney. Although we planned further assessment, he did not revisit our hospital again until 5 years later, again because of right flank pain. Ultrasound and computed tomography scan revealed a large mass lesion with calcification in the right kidney, invasive to the hepatic lobe. The patient underwent curative right nephrectomy and partial right hepatic lobectomy. Pathological analysis demonstrated a nephroblastoma (Wilms' tumor) with predominant epithelial histology infiltrating the hepatic lobe. The patient has been well without tumor recurrence for 15 months after surgery. Conclusions Calcification may be a sign of slow tumor gowth and possibly a favorable prognosis in cases of adult Wilms' tumor.

High-strength ceramic materials are known for their exceptional mechanical properties; however, they are often plagued by brittleness, limiting their applications. Because of the inherent difficulty of dislocation glide and multiplication in ceramics, efforts to overcome the brittleness of ceramics by activating plastic deformation have faced challenges. This work demonstrates that Al2O3–GdAlO3 (Gadolinium Aluminum Perovskite: GAP) eutectic micropillars with submicron-scale fibrous microstructures exhibit remarkable plastic deformability. They displayed engineering plastic strains of up to 5% even at 25 °C, while the micropillars of Al2O3 or GAP single crystals exhibited brittle fracture similar to conventional high-strength ceramics. The plasticity in Al2O3–GAP eutectic was attributed to the activation of primary prismatic slip and secondary basal slip in the Al2O3 phase, which is typically considered inactive at room temperature. These findings suggest that plastic deformability can be achieved in high-strength ceramic materials by fabricating refined eutectic microstructures.Overcoming the intrinsic brittleness of high-strength ceramic materials is required for improving their reliability. Here, the authors report emergence of plastic deformability in ceramics is achievable through refining eutectic microstructures. [ABSTRACT FROM AUTHOR]

In recent years, there has been a high demand in forestry and forest research for the accurate measurement of tree traits from point clouds captured by terrestrial laser scanners. However, the reliability of the calculated values is not sufficient due to the difficulty of accurate registration of each tree over a large area of forest. To solve this problem, we introduce localized multi-view registration for correcting the registration matrix of each tree stem. In addition, we discuss methods for registering the whole point clouds of a forest by using the registration matrices locally calculated for tree stems. Especially, we discuss a method to align tree stem points that do not have sufficient overlapping points required in registration. The proposed method was applied to actual forest point clouds and diameter at breast height (DBH) was compared to the manually measured DBH. Experimental results showed that the proposed method was effective in reducing registration errors and in calculating tree stem traits with high accuracy. [ABSTRACT FROM AUTHOR]

An Al2O3–GdAlO3 (GAP) composite with a fine eutectic microstructure was obtained through local melting and rapid solidification during a flash event. An AC field of 1 kV/cm at a frequency of 1 kHz was applied to a calcined Al2O3–GAP body at a furnace temperature of 1400°C to induce the flash event. The Al2O3–GAP body exhibited local melting through the current path. Solidification proceeded with the maximum cooling rate of about 140°C/s just after the power supply was turned off. Using this flash treatment, a refined eutectic structure with rodlike GAP phases in the Al2O3 matrix was obtained within 1 min. The interphase spacing of the obtained structure was approximately 170 nm, comparable with the finest Al2O3–GAP eutectic material obtained in previous studies. A flash event and subsequent rapid cooling can contribute to forming fine eutectic ceramics with a relatively low furnace temperature and short processing time. [ABSTRACT FROM AUTHOR]

Local mechanical responses near single grain boundaries (GBs) of 9.8 mol% Y2O3‐stabilized ZrO2 bicrystals, SrTiO3 bicrystal, and Al2O3 polycrystal were investigated by nanoindentation at room temperature to reveal single GB contributions to the mechanical properties. Contrary to the concept of the Hall–Petch strengthening, the hardness showed negligible variations among grain interiors, GB vicinities, and just on GBs in the samples. Importantly, the hardness may be underestimated owing to GB grooving in thermally etched samples. Despite the negligible change in intrinsic hardness, the transmission electron microscopy observation of the ZrO2 specimen under impressions revealed dislocation pileups at GBs. These results suggest that single GBs of oxide ceramics prevented dislocation movement but with limited strengthening contributions. This should correspond to the macroscopic Hall–Petch behaviors in oxide ceramics, where the Hall–Petch coefficients normalized by friction stress are significantly smaller than those in metals. [ABSTRACT FROM AUTHOR]

In this study, flash joining experiments were conducted using an AC field on 3 mol% Y2O3‐stabilized tetragonal ZrO2 polycrystal (Y‐TZP) bodies. Furthermore, the necessary conditions to obtain an almost complete self‐joining of Y‐TZP bodies were clarified. The specimens were successfully joined by applying an AC field at 60 mA mm−2 for 80 s at a furnace temperature of 1000°C, thus resulting in a successfully joined specimen with 92% of the flexural strength of the as‐sintered Y‐TZP body. Almost complete self‐joining of Y‐TZP was achieved at current densities above 30 mA mm−2, and input energy densities of >24 J mm−3. Both the input energy density and electric current were critical factors for producing the reliable joining of ceramics. [ABSTRACT FROM AUTHOR]