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In this study, we present a new nonlinear theory for a moving boundary wavemaker of piston-type based on a nonlinear dispersive shallow water model, where the classical Boussinesq equations are employed as a starting point. The new theory is inherently different from the traditional wavemaker theories, such as the usual theories employed for solving the Laplace equation equipped with the free surface boundary conditions by using the perturbation approach. To verify the wavemaker theory proposed in this study, the ratio of the wave height relative to the stroke characterizing the performance of the wavemaker was observed and compared with numerical, experimental, and Havelock's theoretical results, thereby confirming that the results obtained with the proposed theory were in significant agreement. Furthermore, a comparison of the solitary wave generated by the proposed theory and the known exact solution showed that they were in good agreement.

Micostructural change and corresponding effect on coercivity of a NdFeB sintered magnet mixed with small amount of DyMn powder was investigated. In the sintered magnet mixed with the DyMn alloy-powder Dy-rich shell was formed at outer layer of the main grains, while Mn was mostly concentrated at Nd-rich triple junction phase (TJP), lowering melting temperature of the Nd-rich phase that eventually improved the microstructural characteristics of the gain boundary phase. The coercivity of a magnet increased more than 3.5 kOe by the mixing of the DyMn alloy-powder.

In order to increase the coercivity of (Nd, Dy)-Fe-B sintered magnets without much reduction of remanence, small amount of Dy compounds such as and was mixed with (Nd, Dy)-Fe-B powder. After mixing, the coercivity of (Nd, Dy)-Fe-B sintered magnets apparently increased with the increase of Dy compound in the mixture. Addition of was more effective than for the improvement of coercivity. Reduction of the remanence by the addition of Dy compound, however, was larger than expected mostly due to unresolved coarse Dy compound in the magnet. EPMA analysis revealed that Dy was diffused throughout the grains in the magnet mixed with whereas Dy was rather concentrated around grain boundaries in the magnet mixed with .

In an attempt to optimize the magnetic properties of (Nd, Dy)-Fe-B sintered magnets, hydrogenation and post-sintering heat treatment processes were investigated at various hydrogenation temperatures and heat treatment temperatures. The coercivity of (Nd, Dy)-Fe-B sintered magnets hydrogenated at increased to about 1.2 kOe without any detrimental effect on the remanence. Moreover, the coercivity of the magnets was enhanced further by a consecutive and step heat treatment. These results eventually leaded to the reduction of the Dy content in a high coercive (> 30 kOe) (Nd, Dy)-Fe-B sintered magnets, as much as 10%.

Application of precision farming technology to rice cultivation could be an effective measure for rice quality improvement and environment-friendly agriculture. This study was conducted to develope a variable rate pneumatic granule applicator. Previous study reported that application uniformity of the prototype machine (C.V.

In order to obtain ultrafine Nd-Fe-B powder, a spray-dried precursor was treated by reduction-diffusion (R/D) process. And, unlike the conventional R/D process, calcium reduction that is a crucial step for the formation of Nd2Fe14B was performed without conglomerating the precursor with Ca powder. By adopting this modified process, it is possible to synthesize the hard magnetic Nd2Fe14B at the reaction temperature as low as 850 °C. The average size of Nd2Fe14B particles that are uniformly distributed in the optimally treated powder was

TiN-coated SKD 11 was implanted with nitrogen ion and its wear property was examined systematically to investigate whether the wear properties of the hard-coated layer can be improved by the ion implantation. The amount of nitrogen ions implanted on the coated layer was 2×1015, 1016, 1017, and 1018 ions cm−2, respectively. X-ray diffraction revealed that the intensity of the peaks belonging to TiN tended to increase as the ion dose increased, which implied that the ion implantation promoted the formation of TiN in the coated layer. However, the hardness of the specimens increased and then decreased again as the ion dose increased, resulting in an obvious drop of hardness for the ion dose of 2×1018 ions cm−2. Adhesion of the coated layer was apparently improved by the implantation. The overall wear properties were better when the amount of ion dose was 2×1015 ions cm−2.

This paper presents a method for solving structural optimization problems using nonlinear goal programming techniques. The developed method removes the difficulty of having to define an objective function and constraints. It also has the capacity of handling rank ordered design objectives or goals. The formulation of the structural optimization problem into a goal programming form is discussed. The resulting optimization problem is solved using Powell's unconstrained conjugate direction search algorithm. To demonstrate the effectiveness of the method, as a design tool, the solutions of some numerical test cases are included.

Based on microscopic, X-ray diffraction and magnetic analyses of Co-rich Co-Zr and Co-Zr-B alloys, combined with available literature information, the source of magnetic hardness is traced to two phases, pseudohexagonal CoxZr (x ≈ 5), and boron-stabilized hexagonal Co5−xZrBx which has a structure that is derived from the CaCu5 type by boron replacing Co. Both phases have comparable Curie temperatures, 480 to 500°C, and anisotropy fields above 30 kOe. CoxZr crystallizes from the melt but decomposes below 900°C whereas the boron-stabilized phase merely shifts its composition away from binary Co-Zr with decreasing temperature.

We report on the fabrication of Al-doped ZnO (AZO) transparent-conductive oxide (TCO) films on glass substrates by RF- sputtering, their physical properties, and the effect of thermal annealing on the AZO TCO films. The AZO films on glass substrates have a preferred orientation of the c-axis, irrespective of deposition conditions, which means that the AZO films have textured structures along the c-axis. The film thickness and surface roughness in the AZO films are proportional to plasma power and deposition time, while they are inverse-proportional to working gas ratio and working pressure. The AZO films have the optical transmittance over 80 % in the wavelength range of 400 - 1000 nm, irrespective of deposition conditions. The plasma power and the deposition time relatively give a large influence on the optical transmittance, compared to the working gas ratio and the working pressure. The AZO films deposited at room temperature have poor electrical properties, while the thermal annealing under Ar ambient significantly improves the electrical conductivity of the AZO films: an as-deposited sample has an electrical resistivity of 87 Wcm and an electron concentration of 1.3´10 17 cm -3 , while the annealed sample has an electrical resistivity of 3.7´10 -2 Wcm and an electron concentration of 1.2´10 20 cm -3 .

We report on the structural properties of ZnO films grown on (001) Si, (001) GaAs, (0001) Al 2 O 3 substrates and a (0001) GaN template by RF-sputtering. It is observed that all the ZnO films have textured structures with a preferred orientation of the c-axis, irrespective growth conditions, in terms of atomic-force microscope and wide-range X-ray diffractometer. However, it is found that the ZnO films in the ZnO-on-Si and ZnO-on-GaAs are consisted of various domains with different orientations, while the ZnO films in the ZnO-on-Al 2 O 3 and ZnO-on-GaN are consisted of a single domain with the same orientation in terms of the φ-scan of X-ray diffractometer. Moreover, it is found that the ZnO-on-GaN has smaller edge dislocation density and screw dislocation density than the ZnO-on-Al 2 O 3 , which seriously depends on substrate temperature, in terms of the ω-scan of X-ray diffractometer.

Adding small amounts of copper, on the order of 1 to 2 at. %, to FeNdC and FePrC alloys accelerates dramatically the otherwise extremely sluggish transformation to the magnetically hard tetragonal phases Fe 14 Nd 2 C and Fe 14 Pr 2 C. At 800°C the transformation is complete in 24 h for both systems. The nucleation of Fe 14 Nd 2 C and Fe 14 Pr 2 C is greatly retarded, leading to very large grains of 0.5 mm or more in diameter. During annealing the copper is concentrated in a thin phase layer that advances in front of the growing grains of Fe 14 R 2 C. With this method the production of practical quantities of the magnetically hard carbides with the light rare-earth elements has become feasible.

A new human thermal model is developed that accounts for asymmetric environments and includes extremities. The model incorporates 2-dimensional (radial and circumferential) heat transfer along with arterial and venous countercurrent blood flow. Digits to predict toe and fingertip are modeled as arteriovenous anastomoses (AVAs), all of which are important in extremity discomfort.

The distribution of stress during hot pressing of a cast (Fe, Cu)-Nd-B magnet is simulated by simple plastic increment deformation (SPID). The calculated stress components are compression stress ( sigma /sub z/) and shear stress ( tau /sub rz/). The stress component causing the magnetic alignment during hot pressing, sigma /sub z/, tau /sub rz/, virtually plays no role in the magnetic alignment. Generally, sigma /sub z/ is higher at the center of a specimen and decreases gradually along the radial direction to the periphery of a specimen during hot pressing, while tau /sub rz/ is negligible and uniformly distributed throughput the specimen. Random orientation and grain growth of phi are evident at the outer part of a specimen where sigma /sub z/ is very weak. >

Transformation of Fe/sub 17/Dy/sub 2/C/sub x/ to Fe/sub 14/Dy/sub 2/C produces Fe-Dy-C alloys with intrinsic coercivities exceeding 1200 kA/m (15 kOe). After the material is crushed to produce -325 mesh ( >