Nagoya Institute of Technology

About: Nagoya Institute of Technology is a education organization based out in Nagoya, Japan. It is known for research contribution in the topics: Thin film & Catalysis. The organization has 10766 authors who have published 19140 publications receiving 255696 citations. The organization is also known as: Nagoya Kōgyō Daigaku & Nitech.

Magnetism and magnetoelectricity of a U-type hexaferrite Sr4Co2Fe36O60

Abstract: We report on structural, magnetic, and magnetoelectric (ME) properties of a U-type hexaferrite Sr4Co2Fe36O60 prepared by solid state reaction. Samples sintered at 1150–1180 °C in oxygen contain the fewest impurity phases and show highly insulating behavior. Powder neutron diffraction results reveal that a commensurate magnetic order with a (0,0,3/2) propagation vector develops below TN2∼350 K. Corresponding to the appearance of the magnetic order, the sample shows a small ME effect. These results suggest that Sr4Co2Fe36O60 is a room-temperature ME material in which the origin of the ME effect is similar to those of other ME hexaferrites.

Thousands of Voices for HMM-Based Speech Synthesis–Analysis and Application of TTS Systems Built on Various ASR Corpora

Abstract: In conventional speech synthesis, large amounts of phonetically balanced speech data recorded in highly controlled recording studio environments are typically required to build a voice. Although using such data is a straightforward solution for high quality synthesis, the number of voices available will always be limited, because recording costs are high. On the other hand, our recent experiments with HMM-based speech synthesis systems have demonstrated that speaker-adaptive HMM-based speech synthesis (which uses an “average voice model” plus model adaptation) is robust to non-ideal speech data that are recorded under various conditions and with varying microphones, that are not perfectly clean, and/or that lack phonetic balance. This enables us to consider building high-quality voices on “non-TTS” corpora such as ASR corpora. Since ASR corpora generally include a large number of speakers, this leads to the possibility of producing an enormous number of voices automatically. In this paper, we demonstrate the thousands of voices for HMM-based speech synthesis that we have made from several popular ASR corpora such as the Wall Street Journal (WSJ0, WSJ1, and WSJCAM0), Resource Management, Globalphone, and SPEECON databases. We also present the results of associated analysis based on perceptual evaluation, and discuss remaining issues.

Unification of robust design and goal programming for multiresponse optimization—a case study

Abstract: Fixing the levels of input process parameters to meet a required specification of output is a common process quality control problem. Especially when the output has many quality characteristics, and each of these quality characteristics has to satisfy a given specification, difficulties may arise. One such problem was encountered in an injection moulding process. This process was optimized using Taguchi's Robust Design methodology. Details of the process, problems encountered and outcome of optimization are presented in this paper. The optimization study using Taguchi's methodology revealed that the optimum conditions obtained for one response are not completely compatible with those of other responses. So trade-offs were made in selection of levels for factors using engineering judgement. This increases the uncertainty in the decision making process. In this paper, an approach is presented to optimize multiresponses simultaneously using goal programming in conjunction with Taguchi's methodology. Details of modelling, analysis and inferences obtained with relevance to the case are presented. This study revealed that the optimum conditions obtained using goal programming in conjuction with Taguchi's methodology have better goal attainment properties compared to Robust design. To understand goal attainment behaviour of output characteristics for various process conditions, a detailed sensitivity analysis was also conducted. The outcome of this analysis is also discussed in this paper. © 1997 John Wiley & Sons, Ltd.

Novel Preparation Method of Hydroxyapatite Fibers

Abstract: A novel method for preparing calcium hydroxyapatite (Ca10(PO4)6(OH)2: HAp) fibers has been developed. HAp fibers can be prepared successfully by heating a compact consisting of calcium metaphosphate (s-Ca(PO3)2) fibers with Ca(OH)2 particles in air at 1000°C and subsequently treating the resultant compact with dilute aqueous HCl solution. The s-Ca(PO3)2 fibers and the Ca(OH)2 in the compact were converted into fibrous HAp and CaO phases by the heating, and the CaO phase was removed by acid-leaching. HAp fibers obtained in the present work were 40-150 µm in length and 2-10 µm in diameter. The fibers had almost the same dimensions as those of the s-Ca(PO3)2 fibers.