著者
加藤 充美 西村 明 安藤 由典
出版者
一般社団法人電子情報通信学会
雑誌
電子情報通信学会技術研究報告. SP, 音声 (ISSN:09135685)
巻号頁・発行日
vol.100, no.635, pp.43-50, 2001-02-15
参考文献数
6
被引用文献数
5

筆者らはフルート演奏音の倍音の微細な変動のフルート音の品質への影響を研究している。フルート音には、倍音の振幅や周波数の変動とともに息音に起因するノイズ成分が含まれている。このノイズ成分は倍音の変動にも影響を及ぼし、フルート音の品質へも影響している。それらの影響を研究するためには、倍音の振幅や周波数の変動とノイズ成分をまとめて分析し、変動の深さなどのパラメータを変化させて合成し試聴する手法が必要となる。このため、筆者らは解析信号を用いた分析・合成手法を採用し研究を進めている。本報告ではこの手法がフルート音のような倍音の変動のみならずノイズ成分をもつ楽音に対する分析・合成に適している手法であることを示し、その性質を明らかにする。
著者
安藤 由典
出版者
一般社団法人 日本音響学会
雑誌
日本音響学会誌 (ISSN:03694232)
巻号頁・発行日
vol.26, no.7, pp.297-305, 1970-07-10 (Released:2017-06-02)

Using a mechanical blowing apparatus, flute playing was simulated, and acoustical properties of generated tone were investigated. Five sorts of parameters were chosen for description of harmonic structure, and their variations with nine sorts of drive conditions, which were found in a previous work of the author (reported in the last issue of J. A. S. J. ), were measured on a typical instrument (H. Hammig). (Tab. 1). The parameters of harmonic structure (Fig. 1) were 1. The number of harmonics (N): The number of harmonics, of which relative levels are not less than -35dB as compared with the level of the fundamental. 2. Average level of harmonics (M_kdB): M_k=1/(k_1)��^^k__2L_i, where L_i is the relative level in dB of the i-th harmonics. In the low, middle and high registers, k=7, 5 and 3 respectively. 3. Attenuating degree of harmonics level with its order (ZdB/oct): This parameter is expressed by N and M as the following equation. Z=(M+35)log2/(log(N+2)-1/(k_1)log(k!)). 4. Level difference between even and odd harmonics (L_e-L_0): For low register tones, L_e-L_0=1/3(L_2+L_4+L_6)-1/3(L_3+L_5+L_7). For middle and high register tones, L_e-L_0=L_2-L_3. 5. Formant: The term is used in the same meaning as used in phonetic acoustics. The results obtained are as follows: In the low register, M_7 is proportional to the air beam velocity u. Its increasing rate as well as its value at equal velocity are in proportion to the pitch of the tone (Fig. 3, Equation 5. 3). In the middle or the high register, M_5 or M_3 depends on the pitch only (Fig. 4, Equation 5. 4). A fixed correlation was found between N and M_k regardless of drive conditions (Fig. 2, Equation 5. 1 and 5. 2). Therefore the attenuating degree Z is also constant in each of three registers, (15-16dB/oct in the low register, 13dB/oct and 8dB/oct in the middle and high register respectively). L_e-L_0 varies critically with air beam bias e in all three registers (Fig. 6). Anti-formant is observed in low register tones, when u is large(u≧9m/sec) and e is near the soundable limit (about -2. 0mm or 0mm) (Fig. 7). The probable ranges of M_k and L_e-L_0 in the actual flute playing were discussed, based on the above data and those derived in the previous work, and the resultant models of harmonic structure were shown (Fig. 8 and 9).
著者
安藤 由典 田上 亮
出版者
一般社団法人 日本音響学会
雑誌
日本音響学会誌 (ISSN:03694232)
巻号頁・発行日
vol.44, no.8, pp.556-565, 1988-08-01 (Released:2017-06-02)
被引用文献数
4

尺八の一部の管内径による乙-甲間オクターブ音程伸張・短縮は、内径変化の管軸上の位置と極めて規則的な関係がある。この現象を利用し、所与の尺八を所要の音律に修正する計算機プログラムを構成した。これを本曲用尺八、練習用尺八及び19世紀に作られた初期芸能用の名器に適用し、一例として、±10セント以下の偏差で、演奏会調平均律に修正する構造仕様を得た。また、この寸法変化による音色性能の変化を検討した。
著者
安藤 由典
出版者
一般社団法人 日本臓器保存生物医学会
雑誌
Organ Biology (ISSN:13405152)
巻号頁・発行日
vol.24, no.1, pp.7-12, 2017 (Released:2017-03-31)
参考文献数
30

Allogeneic islets are transplanted to many type 1 diabetic patients in the world in recent years. But that situation is limited by the short supply of donner islets, and the recipients must continuously use immunosuppressive agents which may have deleterious effects on the islets. In order to resolve these problems, we can use the bioartificial pancreas (BAP) which can separate xenogeneic or allogeneic cells from the immune system cells of the recipients. So many basic reseach and animal examinations about various types of BAP have being examined to this date. Recently, clinical trials have started on several BAP. The purpose of this review is to show the current status of clinical trials about the BAP.
著者
安藤 由典
出版者
物性研究刊行会
雑誌
物性研究 (ISSN:05252997)
巻号頁・発行日
vol.62, no.5, pp.612-619, 1994-08-20

この論文は国立情報学研究所の電子図書館事業により電子化されました。
著者
安藤 由典 田中 祥司
出版者
一般社団法人日本音響学会
雑誌
日本音響学会誌 (ISSN:03694232)
巻号頁・発行日
vol.48, no.8, pp.556-563, 1992-08-01
被引用文献数
6

バロック音楽に望ましいリコーダ音の倍音構造は、(1)奇数次倍音が偶数次倍音に比べて優勢であり、(2)高次倍音が比較的豊富なこと、である。この特徴を得ると共に、最低音域を十分な音量で鳴らすのに必要な吹鳴可能最大流速を確保する構造上の工夫を、ボイシング寸法可変の頭部を製作して、実験的に調べた。その結果は(1)はボイシングによって、(2)はエッジを鋭くすることで実現していることが分かった。望ましい寸法は、エッジ先端の曲率半径が0.2mm程度であり、ボイシングは大きさが(流線方向×これと直角方向)の値で、0.5〜1.0mm^2、形は流線方向と直角方向の比で2:1程度である。一方、管の共鳴特性は上記の特徴を得るのに寄与していないことが、これまでの尺八研究と同じ方法による計算で示された。この点、尺八が管の共鳴特性で、所要の音色性能を得ていることと対称的である。
著者
安藤 由典
出版者
一般社団法人日本音響学会
雑誌
Journal of the Acoustical Society of Japan (E) (ISSN:03882861)
巻号頁・発行日
vol.7, no.2, pp.99-111, 1986-03
被引用文献数
4

By the calculating method reported in the previous paper, the input admittance curves of six shakuhachis of 4 types were obtained. In this paper, the played pitch frequencies were measured and their relation to the correspondent peak frequencies of input admittance was found. From this relation, the magnitude of the acoustic inertance generated at the mouth end and resonance curves under the playing state were calculated. As for the levels at the multiples of the lowest two peak frequencies of resonance curve, their average varying rate per 20 cents change of the pitch frequency was estimated. The rate is about 3. 0 dB and 3. 6 dB in the lower and higher octave respectively. This rate suggests how much the harmonic levels of played tones vary with the performance of the pitch control techniques as "meri" or "kari. " Based on these values, the arrangement of resonance frequencies which is desirable for the musical expression aimed in pitch control was discussed.
著者
安藤 由典 大谷木 靖
出版者
一般社団法人日本音響学会
雑誌
Journal of the Acoustical Society of Japan (E) (ISSN:03882861)
巻号頁・発行日
vol.6, no.2, pp.89-101, 1985-04
被引用文献数
1

The input admittance measuring system for shakuhachis was constructed and its accuracy was examined in detail. Then basing on the comparison with input admittance measurement of various pipes by the use of this system, input admittance calculating method was improved for the purpose of obtaining sufficient validity to be used for design practice of the shakuhachi or any other woodwinds. The pipes used in the comparison were 4 straight tubes with and without side holes and two real shakuhachis. The maximum error of the measuring system was estimated to be 5. 3 cent in peak frequency and 2. 2 dB in absolute level. The average differences of calculated frequency and level of input admittance peaks from those measured were less than 3 cent and 3 dB respectively. As for levels of higher peaks relative to the first peak as well as the levels at the multiples of the two lowest peak frequencies, the calculated values showed well coincidence with those measured.