An optical fiber grating demultiplexer-multiposition switch having seven demultiplexing channels and six position-switching channels is demonstrated. This device consists of a unique fiber array in which 42 output fib...
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An optical fiber grating demultiplexer-multiposition switch having seven demultiplexing channels and six position-switching channels is demonstrated. This device consists of a unique fiber array in which 42 output fibers are aligned radially around an input fiber, a single gradient-index (GRIN)-rod lens and a rotatable blazed reflection grating. In this device, seven demultiplexing channels can be switched to six different directions by rotating blazed reflection grating. Therefore, this device can realize total transmission channels of 42. The device had a working band of 0.64-0.88 /spl mu/m, a channel separation of 35-42 nm and a 3 dB band width of 18-22 nm. The deviations of center wavelengths among the switching channels were suppressed less than 3 nm.
Proposes a "multi-valued neural network" (MNN) which can distinguish patterns (or failure types) on the basis of the probability distributions of ambiguous feature parameters (or symptom parameters). In most...
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Proposes a "multi-valued neural network" (MNN) which can distinguish patterns (or failure types) on the basis of the probability distributions of ambiguous feature parameters (or symptom parameters). In most cases of pattern recognition, the knowledge for the recognition are ambiguous. In these cases, the learning data (the diagnosis knowledge) for the MNN must be acquired in some way. Therefore, the knowledge acquisition method for the MNN by using rough sets is also proposed. Several examples of failure diagnosis verify that the methods are effective.
In the field of failure diagnosis of plant rotating machinery, one of the most important and most difficult things is the identification of symptom parameters (SP). By using the optimum SP, failures can be sensitively...
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In the field of failure diagnosis of plant rotating machinery, one of the most important and most difficult things is the identification of symptom parameters (SP). By using the optimum SP, failures can be sensitively detected and the failure types can be distinguished. However, there is no acceptable method for extracting the optimum SP. In order to overcome this difficulty and insure highly accurate failure diagnosis, in this paper, a new method called "self-reorganization of symptom parameters" has been proposed by using genetic algorithms (GA). And the new method can also be applied to other pattern recognition problems. By applying the method to many practices, the optimum SP can be quickly discovered. Several examples show that this method is very effective.
When building up a fuzzy diagnosis system for machinery diagnosis, fuzzy relation between failure symptoms and failure categories must be defined for fuzzy inference. However, it is not easy to search out the failure ...
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When building up a fuzzy diagnosis system for machinery diagnosis, fuzzy relation between failure symptoms and failure categories must be defined for fuzzy inference. However, it is not easy to search out the failure symptoms by which all failure categories can be distinguished perfectly and automatically. In order to resolve the problem, we proposed (1) a new type of symptom parameter function called off-group type of symptom parameter (OGSP); (2) the identification method of the OGSP; (3) the identification method of the membership function of OGSP; (4) the algorithm of sequential fuzzy inference by using the OGSP and its membership function for diagnosis. The efficiency of the above methods has been verified by applying them to the ball bearing diagnosis system.
The entrainment between talkers in face-to-face interaction plays an important role in the smooth exchange of information. In this paper, the physiological signal entrainment in face-to-face interaction was analyzed o...
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The entrainment between talkers in face-to-face interaction plays an important role in the smooth exchange of information. In this paper, the physiological signal entrainment in face-to-face interaction was analyzed on the basis of heart rate and its variability as indices, based on the previous known fact that alteration of cardiac rhythm has been used as an indicator of the emotional state. The subjects consisted of two pairs of mothers and healthy infants aged 5 and 9 months as a primitive form of communication, and one pair of male students. The existence of physiological signal entrainment was demonstrated from some examples of synchronized time changes of heart rate variability in both mother-infant interaction and adult conversation. This finding suggests the entrainment is biologically essential to human communication and it could be applicable for improved human-robot interaction.
A Reed-Solomon coded type-1 hybrid ARQ scheme based on a selective-repeat (SR) ARQ with multicopy retransmission is proposed for mobile/personal satellite communication systems of a transmitter and a receiver both wit...
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A Reed-Solomon coded type-1 hybrid ARQ scheme based on a selective-repeat (SR) ARQ with multicopy retransmission is proposed for mobile/personal satellite communication systems of a transmitter and a receiver both with finite buffer. The performance of the proposed scheme on fading channels is analyzed. The basic idea of the strategy is the use of two modes; the SR mode and the multicopy mode. In the latter mode, erroneous blocks stored in the /spl nu/N block transmitter buffer are alternatively retransmitted multiple times when /spl nu/ consecutive retransmissions in the SR mode are received in error, where N denotes round-trip-delay in blocks. Numerical and simulation results for /spl nu/=1 show that the proposed scheme presents better performance than the conventional SR+ST scheme 2 of the 2N block buffer by Miller and Lin (1981).
Assembly Instruction Manuals usually consist of both explanation and illustration. An expart who has rich knowledge on mechanical assemblies is able to under stand illustration without reading explanation. It is, how ...
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Assembly Instruction Manuals usually consist of both explanation and illustration. An expart who has rich knowledge on mechanical assemblies is able to under stand illustration without reading explanation. It is, how ever, difficult for a novice to read an instruction manual without referring to both of them. People may probably read explanation and see illustration alternately. It is difficult to model the human method because switching between two processes depends on knowledge level. In this paper, a method is proposed as the first version for integrating interpretation by both explanation and illustration.
We carry out a theoretical analysis of Kerr bistability in a double-coupler optical fiber loop resonator in a case of two coexisting input optical fields, and we propose a set-reset (S-R) flip-flop operation that uses...
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We carry out a theoretical analysis of Kerr bistability in a double-coupler optical fiber loop resonator in a case of two coexisting input optical fields, and we propose a set-reset (S-R) flip-flop operation that uses two input ports. We found that in the optimum case set and reset operation can be achieved at relatively low optical input powers.
The singular stress field around a sharp notch tip is expressed as a sum of two independent fields: a symmetric field with a stress singularity 1/tau(1-lambda 1) and a skew-symmetric field with a stress singularity 1/...
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The singular stress field around a sharp notch tip is expressed as a sum of two independent fields: a symmetric field with a stress singularity 1/tau(1-lambda 1) and a skew-symmetric field with a stress singularity 1/tau(1-lambda 2). The intensities of the symmetric and skew-symmetric singular stress fields are defined in terms of constants K-I and K-II, respectively. In this study, a plane problem of a strip with single or double edge notches under tension or in-plane bending is considered. The bisector of the notch may be inclined to the edge, so that the two singular stress fields with different singularities may be created simultaneously at the notch tip. The body force method is used to calculate the stress intensity factors K-I and K-II. In numerical analysis, basic density functions of the body forces are introduced to characterize the stress singularity at the notch tip. The advantages of this technique are the high accuracy of results, due to the smoothness of the unknown weight functions, and the presence of the direct relation between the values of K-I and K-II and the values of unknown weight functions. The stress intensity factors are systematically calculated for the various geometrical conditions.
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