Effects of data compression, to save the processing time in the P-wave recognition program with the adaptive correlating filter (ACF), on the performance of the ACF has been studied.All QRS or QRST regions were eliminated from the record to compress ECG data.
Two indices were adopted as criteria for evaluating the effects. One was derived on the basis of the performance characteristics of the ACF, while the other was the mean error probability in detecting P-waves by using the ACF.
In result, it was shown that the method for data compression could make up for the loss of the P-wave information caused by the data reduction. So the data reduction proposed here makes data compression feasible with little deterioration of the ACF performance.

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The adaptive correlating filter (ACF) is effective to detect P-waves in ECG's buried in noise or overlapped with the QRS or T-waves. In this paper, an index has been applied to the evaluation of three templates (i. e., a Gaussian waveform, a typical P-waveform obtained from normal ECG and segment data involving a P-wave taken out from each ECG being processed) used in the P-wave segmentation procedure as a pre-procedure of the P-wave recognition program with the ACF. The index was highly reasonable in the sense that the derivation of the index was based on the performance characteristics of the ACF.
As a result of the evaluation using 14 cases of ECG's with A-V block, the Gaussian template was shown to be superior to the other templates.

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Detection of the P- wave within associated noise and other background signals is difficult. An Adaptive Correlating Filter has been developed to solve this problem.
The adaptive property of this filter arises from its iterative correlation and averaging of data, making possible recognition of specific waveforms not known in advance. Its statistical property makes it useful for practical ECG processing in the identification and resolution of the P-wave. The procedure of P-wave segmentation, which is required before using this filter, is also discussed.
The filter has helped identify a P-wave with a low signal-to-noise ratio. It has also proved useful in the case of arrhythmia, such as complete A-V block where the P-wave overlaps the QRS complex and the T-wave.
This method should be useful for P-wave recognition in ECG auto-analysis of arrhythmia.

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媒質の非線形パラメータB/Aの絶対値の空間分布を、二つの音波交差時の非線互作用を利用して測定する場合における解像度向上に関する処理手法について検討した。すなわち、従来は考慮されていなかった測定対象空間内における音速分布、並びに境界面におけるポンプ波の反射が測定に与える影響について、B/Aの単純な空間分布モデルを想定して理論的な見当を加えた。また、ベンジルアルコール並びに2-プロパノールを測定試料とし、水中に層状に配置して得られた実測結果にこの処理手法を適用すると、解像度が向上することを示した。

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ロスビー波の三波共鳴非線

互作用は回転球面上2次元乱流において重要な役割を果たすと考えられることが多いが，ロスビー波の三波共鳴非線互作用のみでは流れ場の構造形成は起きないことを数値計算によって提示する。また，三波共鳴波全体を完全にクラスタ分解することは不可能であり，クラスタ間相互作用を無視することはできないことにも言及する。

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In this paper, I shall consider the meaning of the idea that matter is potentiality and form is actuality by dealing with the problem of the unity of matter and form in Aristotle's Metaphysics H 6 According to the orthodox interpretation of H 6, Aristotle attempts to solve the problem of the unity of the definition signified by genus and differentia It is true that Aristotle refers to the definition of 'man' as 'two-footed animal', but the reference to H3 at the beginning of H 6 shows us that he is concerned with the problem of the unity of the definition combining matter and form In fact, Aristotle tentatively defines 'cloak' as 'round bronze' in order to show the problem of the unity of a definition So it is the problem of the unity of the definition composed of matter and form that should be solved by the concepts of potentiality and actuality in H 6 But Aristotle turns to the problem of the unity of matter and form, not of the definition composed of them For in his view, to give an account of the unity of matter and form is to give an account of the unity of the definition composed of them In connection with this, how should we understand the unity of the composite of matter and form ? Is it the same as the existence of a particular substance? To answer these questions, I turn to the argument of Z 17 before I examine Aristotle's solution of the problem of the unity of matter and form Aristotle's concern in Z 17 is to seek the cause by which matter is something For example, these bricks and stones are a house by the essence or the form of the house Moreover, Aristotle argues that the essence or the form is the primary cause of the existence of a particular substance by pointing out that the status of the cause is different from that of the material elements In other words, the essence or the form is the cause by which the composite of matter and form exists So what is sought in Z 17 is the cause of the existence of a composite But Aristotle treats the problem of the unity of matter and form in H 6 and he says that the unity of matter and form has no cause except the efficient cause Then the unity of matter and form should be distinguished from the existence of a composite Aristotle solves the problem by applying the concepts of potentiality and actuality to matter and form I examine how he does that by interpreting the controversial passage in which he gives us a concrete example And I find that we fall into difficulty when taking a sphere to be the composite of e g bronze and sphericality Then I explain the significance of 'what is potentially sphere being actually sphere'

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Aristotle's formulation of perception as receiving form without matter in De anima II. 12 has proven one of the most challenging phrases in his corpus. Recent debates between spiritualists who believe that no corresponding material changes accompany mental changes and literalists who think that a literal change such as an eye becoming red happens when one perceives red reconfirm the phrase's ambiguity. In this paper, I will stand by neither of these two positions but will adopt a third position and argue that when one perceives, contra spiritualists, a corresponding material change occurs alongside a mental change, and, contra literalists, the material change is not literal. Both spiritualists' and literalists' interpretations of the formulation (and those of some who stand by the third position) posit a distinction between "receiving form without matter" and "receiving form with matter" and ascribe perceptual changes and non-perceptual changes respectively to each, but as different processes of change; for example, spiritualists ascribe the perception of warmth without any corresponding material changes to the former and becoming warm by the patient herself to the latter, while literalists ascribe the perception of warmth that occurs concurrently with the patient becoming warm by herself to the former and the patient becoming warm by receiving warm matter inside herself to the latter. However, I do not see Aristotle as making a distinction between receiving form without matter and with matter. Rather, he distinguishes between material changes according to proportion that are caused by sensibles, such as colour, and material changes not according to proportion that are caused by that which possesses sensibles, such as gold. The former can be further divided into two subclasses: perceptual changes which accompany the reception of form, and non-perceptual changes which do not accompany the reception of form. By reconstructing Aristotle's classification of changes in De anima II. 12, I will argue that Aristotle refers to mental changes by the phrase "receiving forms of sensibles" as spiritualists have pointed out, but that because his phrase "without matter" has a limited meaning, he does not deny the possibility of every material change, and that the process of material changes according to proportion which accompany the reception of form does not have to be identical with that of material changes according to proportion which are literal and do not accompany the reception of form because the proportions of sense-organs and non-perceptual matter are not necessarily identical.

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In De Anima II 1 Aristotle applies the form/matter distinction to the soul-body relation and introduces what J. Ackrill calls the "homonymy principle", according to which a dead body is not a body, except homonymously, that is in name. Ackrill argues that this account is infelicitous, because the homonymy principle suggests that a body cannot exist without soul, though Aristotle's hylomorphism requires that matter could be regarded as existing without form. In this paper I will attempt to show that this difficulty stems from understanding Aristotle's hylomorphism exclusively on the basis of the model of artifacts, and that it is not necessary in hylomorphism that "the matter can be picked out in such a way that it could be conceived as existing without the form," as Ackrill says. Aristotle introduces the homonymy principle to clarify the sense in which soul is essence. He explains it by an example of an instrument, i. e., an axe, and says that the essence of an axe is its function, without which it would not be an axe except homonymously. But he implies that the example of an axe is not appropriate because an axe is not a natural thing, and says soul is "logos of a certain kind of natural body having within itself a source of movement and rest." Aristotle thinks the distinction between natural things (esp. living things) and artifacts is relevant to the form/matter relation. In the case of living things the matter, which is said to have within itself a source of movement and rest, cannot be independent of the form, and must be conceived only as already having potentiality to realize a particular activity. Such matter is a kind of proximate matter, as different from that which is required in the analysis of change. Aristotle says the body as matter is "potentially such as to live," and on the other hand regards it as that which[actually]possesses soul. Why does he say so? In Metaphysics 8 he distinguishes two kinds of δυναμι&b.sigmav;(potentiality), i. e., dunamis related to movement, and dunamis related to energeia. The former has its end outside itself, and in its completion what has the dunamis acquires a new property. The latter has its end in its actuality itself, and in its completion what has the dunamis continues to be the same. This dunamis and its actuality is the same being. The body as matter is potentiality in the latter sense, and therefore it can be said to live potentially, even if it lives actually. This makes it possible that the soul itself is said to be not only a formal cause but a final cause, whereas the final cause of an artifact is outside itself(e. g., a user of an instrument). The body as matter is the heterogeneous parts of living things. Each part can be called so only in relation to the whole, which is specified by form. The matter is not in itself a definite thing, and we must refer to its form to identify it. Therefore the body is said to exist potentially, even if it manifests its own dunamis as a part of the living thing as a whole. Aristotle often explains the concept of matter by examples of artifacts, which are useful to clarify the distinction between form and matter. But it does not follow that in Aristotle's hylomorphism matter is always contingently enformed. In the case of a living thing, its matter must be a particular kind of matter, which is already directed toward a particular activity. In general matter must not be conceived as a thing which is identified in itself, and it is that aspect of a thing which can be understandable only in connection with its form, which clarifies an organized unity of the thing.

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In Motu Animalium (MA, hereafter), Aristotle repeatedly says, "The soul moves the body", "Desire moves the animal", etc.. Commentators, who interpret Aristotle's philosophy of mind in a non-dualistic way, would find these claims perplexing, since they appear to imply that the soul is a non-material substance, separable from body, and imparts motion to body. Martha Nussbaum, one of the most influential proponents of the functionalistic interpretation of Aristotle, argues that the capacities of the soul are called "the movers of the animal" because of their role in the explanation of goal-directed motions, not of their causal agency, and so his claims there do not imply the Cartesian or Platonic conception of the soul as an incorporeal agent. However, although this sort of view is dominant in the recent literature, I don't think that it is a plausible reading. A number of passages in MA suggest that Aristotle takes the animal soul, or part of it, to be a causal agent in the quite literal sense, by which an animal can be moved to act. That wouldn't be so embarrassing if you saw that it is his theory of causation and other connected doctrines that lie behind the account of animal movements in MA. My aim in this paper is to show that this is a crucial aspect of Aristotle's philosophy of mind and action developed in MA. The first part of my discussion treats the MA's account of the initiation of animal (and human) movements. Aristotle explicitly says that the capacities of the soul, such as perception, imagination, thought and desire, have by themselves the power to alter a bodily organ (on his view, the heart). It is important to notice that he thinks such an alteration occurs because an animal's soul receives a certain form from the external world and thereby acquires the power to change its physiological state. The idea is that the form itself, both internal and external, has the causal efficacy by virtue of which the alteration in an animal at the material level can be brought about. I show that this idea is the key to understanding Aristotle's view, and that he makes use of it here on the basis of both the theory of formal and efficient causation he has established in Physics and his other writings, and the view which might be called "isomorphism" developed in De Anima. Next, I turn to another passage from MA. It is supposed to strongly support the functionalistic interpretation because Aristotle seems to introduce the connate pneuma to provide a material basis for mental causation. However, a careful reading will show that he insists there is a distinct type of alteration that the soul itself, rather than its material correlate, would undergo, which he calls "energeia" elsewhere. Here too he holds that a physiological change like that of pneuma takes place just as the result of this formal level causation. I conclude by suggesting in brief that such a picture of Aristotle's philosophy may throw some light on the problem of mental causation.

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According to Aristotle, 'a this' is a substance because it is a subject, and form is the primary substance because it is identical with essence. What notion underlies these two criteria of substantiality? I think the concept of substance has its root in the notion of ipseity or selfhood, by which I mean the character of those things which what-questions are intended to hit and to reveal. The a;to-question is intended to reveal the very self of the thing in question. There are at least three points where the notion of ipseity plays a decisive part in Aristotle's ousiology : 1. The distinction between the category of substance, which Aristotle sometimes calls 'the what is', and the other categories corresponds to the distinction between the what-question and the other types of question. If one asks"What is it?" about something, the thing mentioned in answer to the question, i.e. a this, is not the quality nor the quantity of that something but its very self, which is at the same time the subject of the other characteristics hit by the other questions. Here the subject has the character of ipseity. 2. Form, matter and the composite of both are possible answers to the what-question when it is asked about a this itself. Each of them is not that which a this is, but that which is a this(Met. H2). We may ask in what sense matter, which is not per se a this according to Aristotle, can be the very self of a this. Matter is that which per se changes, aims at something, and so is per se 'not yet...but sooner or later...'. Thus if something is understood to be in such a way as 'for the present...but...', the very self of that something is unambiguously its matter, which the what-qnestion is intended to reveal in this case. Matter is a substance to that extent. 3. Essence, a kind of 'the what is', is identical with form in that both of them hit the very self of something insofar as that something has already reached its own end and has no more 'further' beyond itself, the character of which Aristotle calls energeia. To sum up, the concept of substance embodies the notion of ipseity, which seems to have determined the character of Greek philosophy in general. Unlike any other school of philosophy, it sought for the very self of beings, whether in the direction of matter or of form. In this tradition, Aristotle was the first to notice that the very self of beings is not itself a kind of being, but rather beingness. This enabled him to interpret form and matter in terms of modality. It is with respect to this that he criticized both the Presocratic philosophers who identified matter with a specific being like water, air etc., and the Platonists who thought form to have the same modus of being as beings.

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How are the following three propositions related to each other in the Phaedo? A Something is beautiful. B Something has(echei)beauty(immanent form or character). C Something participates in (metechei) beauty (transcendental Form). Some scholars(e. g. Vlastos, Fujisawa)identify A with B and consider C is the cause(reason) (aitia)of both A and B, but in my view this interpretation is open to further discussion. Plato does not identify A with B, but rather thinks B may also be the cause of A. This paper further considers this point. If anything else is beautiful besides beauty itself, it is so only because (dioti) it participates in that beauty(100c4-6). This sentence suggests that C is merely the cause(dioti)of A, and in the following passages of the Phaedo it is never said that B is caused by C. Simmias overtops Socrates because (hoti) Socrates has smallness in relation to Simmias' largeness(102c2-5). "Simmias overtops Socrates" is similar to "Socrates is smaller than Simmias" and "smallness" is immanent form. If so, the import of this sentence is that B is also entitled to be the cause(hoti)of C. In this respect, the next sentence is important. Nothing else makes a thing beautiful except beauty itself, whether by its presence or communion or whatever the manner and nature of the relation may be(100d4-6). The meaning of the word "presence(parousia)" is close to "echein" and "communion(koinonia)" to "'metechein". Of course the immanent form (beauty)does not appear clearly in this sentence, but the ambigious expression "whatever the manner and nature of the relation may be" alludes to it. If this understanding is correct, the role of this sentence is to suggest that A can be caused by either B or C. At 103c10f. Socrates introduces some other items, namely, "fire", "snow", "three" etc. The status of these is controversial, but I take them as immanent forms, because at the advance of their opposites, say, "cold", "hot", "even", they get out of the way or perish. Since immanent forms, "largeness", "smallness", are prescribed similarly at 102d5-103a2, "fire", "snow", "three" must be immanent forms(cf. Keyt). At 104d1-7 these items are defined thus : There would be those that compel whatever they occupy to have not only their own form but the form of some opposite as well(d1-3). Anything occupied by the form of three must be not only three but also odd(d5-7). This definition suggests that when something is occupied by "three" (immanent form), it is compelled to have not only "three" but "odd", so that it must be not merely three but odd. That is to say, in these two sentences too, it is suggested that possession of an immanent form causes predication. This becomes more obvious at 105b5-c6. In this passage, "fire", "fever", "one" are immanent forms. And it is clear that their immanence in something is the cause of predication. If the above consideration is correct, we can conclude that in the Phaedo A(predication) is caused either by B (possession of immanent forms) or by C (participation in transcendental Forms), but C is never the cause of B. Why, then, is B introduced in the argument? Is it necessary to Plato's argument? To answer these questions we must consider two points. One is that this argument is subordinate to proof of the immortality of the soul. In the argument soul is parallel to immanent forms. A body lives by the immanence of soul with it(105c9-11). As "three", which brings "odd" to something, can not admit "even" (104e8-10), so soul, which brings life to body , can not admit death, and therefore is immortal(105d3-e9). To prove this, Plato has to introduce B, namely, immanent

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状態変数表現は，独立変数と従属変数以外に内部変数を含む表現形式である．内部変数の計算は線補性問題の求解に帰着する．また，状態変数表現可能な対応を線補性対応と呼ぶ．本発表では，まず，線補性対応全体のサブクラスであるクラスＰとクラスＵＬＴを導入する．これらはそれぞれ，状態変数表現の特殊形式であるＰ表現とＵＬＴ表現によって特徴付けられる．次に，クラスＰとＵＬＴ及び区分線形関数全体が一致することを明らかにする．一方で，状態変数表現に関する最小実現問題を定式化する．特に，ＵＬＴ表現に話を限定した場合の最小実現問題について議論する．そこでは，与えられたＵＬＴ表現の最小実現性について考察し，表現の最小実現性を，状態変数の冗長性によって特徴付けることを考える．その中で，冗長性に関連するＵＬＴ既約性の概念を導入する．また，ＵＬＴ既約性に対する１つの必要十分条件を与える．

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本研究では，接触部を剛体近似した多衝撃問題に関して，従来法よりも適用範囲が 広く，計算負荷が小さい線補性モデルの一手法を提案した．さらに線補性問題の精度保証定理を導出し，衝撃問題の数値的不具合がモデル化誤差と数値計算誤差のどちらに起因するのか特定する手法を示した．最後に，構築した動力学解析手法を応用して，２次元微小重力模擬実験システムを用いた数値シミュレーションを行った．

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