A regulation system is indispensable to the nuclear industry to prevent nuclear accidents. The Japanese regulatory authority intended to enhance nuclear safety level by changing the current inspection system three years ago. The new design of the system will be enforced at the beginning of next year. This paper describes characteristic features of the new system with application of condition based technology. Application of the condition monitoring system is the first attempt in Japan and it is expected to enhance reliability of machines and components. A regulatory procedure which electrical enterprises should follow will be different from the current one with the maximum operation period of 24 months.

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This paper describes the development of civil aircraft maintenance inspection. Aircraft maintenance inspection has been changing along with the development of aircraft design and maintenance method. Latest aircraft design is called the damage tolerant design, which require more severe usage of maintenance inspection. The maintenance inspection has become more and more important to support aircraft integrity and safety. This paper explains the history of maintenance inspection and describes the latest maintenance inspection method and its effective application.

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In this research, a basic research on elucidation of fracture mechanisms of the laminated materials by impact load for a new damage tolerant design method was done. Laminated materials of three ply was used, and the impact three-point bending test was conducted. A high-speed video camera was used, and dynamic fracture toughness, K_<CD>, was calculated by the digital image correlation method and the caustics method. As a result, the K_<CD> for the digital image correlation method and the caustics method showed similar tendency. When the mixed-mode ratio was large, dynamic fracture toughness K_<CD> increased. Furthermore, it was shown that the interface strength, fracture toughness of each material and mixed-mode ratio was related to the fracture morphology.

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Compound material has more performance than single material. It is important to evaluate the stress state when the crack exists in such a different phase axis obviously on the safety design of the machine structure. Then, we used epoxy resin for the sample material in this research. Different phase axis that inserted a surface crack axially is produced. We experimented putting the static loading on the axis. We used photoelasticity method and method of caustics hybrid for the analysis, and calculated the stress intensity factor. The results from these experiments will be presented at the conference.

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It is one of the easily imaginable materials that it has the major plus in many sides compared with another material, and use in the field expands to the polymeric material perhaps. The polymeric material with the especially excellent mechanical properties includes the polycarbonate etc. However, the phenomenon that is called a craze when destroying it is generated in the polymer material and this mechanism is still opaque. Then, this report compared the influence on the craze that occurred in the test piece that changed the environment with the standard one.

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The accident which made the driven vehicle part cause for vehicle which is being used daily occurs frequently. Maintenance and non-destructive test are being performed, but to stop those accidents from happening it's the current state that it isn't possible to stop an accident perfectly. A production model was produced by epoxy as modeling of a hub by this research. To reproduce the real load which is being driven by an experiment again, a stress analysis is performed in the state which made a hub model take one concentrated load. To do a stress in three-dimension analysis of a hub, stress distribution chart is drawn from the isochromatic curve stripes which were observed using photoelastic approach based on the data an experiment gave. I'd like to find the part I'm doing stress concentration of and contribute to improvement of safety more than the above.

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Rotating machinery is widely used in the industrial plant, for example, power plant, chemical plant, mass-production plant and so on. In order to ensure safety operation of the rotating machinery, vibration condition monitoring of the machinery can play a crucial role. In this study, the cantilever type of vibration energy regeneration system is designed for a self-powered monitoring system of vibration condition monitoring applications of rotating machinery. The mechanical resonant frequency of piezoelectric bimorph cantilever will be tuned to the operating speed of the machinery. Recently, new d31 type Macro-Fiber Composite (MFC, piezocomposite) can be commercially available. Due to the d31 configuration, electrical impedance of new MFC is much smaller than that of previous d33 type MFC. This study experimentally compares the ability two types of MFC, d31 and d33 configurations, to generate electrical energy when subjected to mechanical vibration.

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In order to detect a transverse crack due to fatigue of rotor, this paper investigates theoretically and experimentally the change of resonance curve of amplitude and phase lag for various angular positions of unbalance vs crack angular position. In the analysis, stiffness of the crack rotor is represented by higher order sinusoidal function and the equation of motion is solved by using perturbation method. Each element of the solution is discussed from the view point of detection of crack and the amplitude and phase angle are compared with the experimental results. The effect of crack on the amplitude and phase angle of the resonance is discussed. Finally the characteristics of the crack is clarified and the guide for detecting the crack is proposed.

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This damage analysis system for large-sized bearings and driveshafts is a maintenance system that enables diagnosis and preventive maintenance without disassembling components in service to inspect for flaking failure, wear, etc. Sensing and abnormality diagnostic technology during low-speed rotation with large external disturbance and energy-efficient, high-performance wireless technology were indispensable to the development of this system. Although verification by a system model is still being carried out, development is nearly complete, a therefore a portion of the concerned technology is introduced in this paper.

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A new monitoring method of batch processes using relationships between dynamic time warping (DTW) and external variables is proposed. DTW has been used as a preprocessing tool for batch process monitoring based on multiway principal component analysis (MPCA) in order to align batch data from various batch lengths by expanding and/or shrinking time axis of data trajectories flexibly. Although MPCA has experienced many successes, the fault detection ability is limited if a fault affects only the progress speed of the process and doesn't change the correlation structure between variables. In this study, another usage of DTW is proposed to overcome this difficulty. If the time warped information of DTW is correlated with external variables of the process such as temperature, initial concentration of materials and so on, changes of input-output relations between external variables and time warped information become good indicator of fault occurrences. The proposed method is applied to a fed-batch penicillin fermentation process simulator to show its effectiveness.

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A cogeneration system, i.e., CGS, is the system that supplies both the electricity and hot water or steam to the plant in the case of emergency or on demand of low energy cost. Although this system is very important in the plant, only simple diagnosis techniques are often used. One of the reasons is that a system is very complicate and one trouble changes many parameters in the system. To operate the CGS with higher reliability and efficiently, an advanced diagnosis system is required. One of the techniques for an advanced diagnosis is model-based diagnosis, in which system load and outside air temperature etc. are taken into account. In this paper, first we built the CGS model including thermodynamic and kinetic characteristics, and then modified some parameters to simulate troubles. By identifying parameters in the model, we can recognize the occurrence of trouble and the location of a fault. Using proposed technique, we can detect faults in the system.

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When we are creating a diagnostic support system for troubles, the expertise is unnecessarily if we create it upon a statistical-based system, but often the lack of real data can become the problems. In addition, using a model-based system, the close analysis is possible, but there are some problems, difficulty modeling the application objects and necessity of expertise diagnosing the analysis results. In this study, we are propose a better diagnosis system fusing model and semantic networks in order to solve those problems and consider the new system.

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Crane inspections of the ceiling area of the drive system, and continuous rotation for a short time, the inspection is difficult to check while driving in the quantitative portion of rotation. The timing of replacing the wire rope, Hanging record number of crane operators are determined on the basis of the challenges in life, leaving an estimated accuracy. So, in the hot metal crane equipped with an online vibration diagnosis system and the load frequency of wire rope for the first time. Rainflow method applied to the structure of the crane fatigue damage and estimate the diagnostic system is proposed.

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In this paper, a method to identify the geometrical shape and the location of the defect embedded in a concrete structure by processing the thermal image of the structural surface acquired by infrared thermography is presented. In the proposed method, the structure is modeled as a homogeneous infinite plate whose boundary condition on the observed surface is known. A layer-by-layer inverse analysis using a regularized interlayer transfer matrix based on 2D Fourier transform is carried out to obtain the sharper image of the defect as well as the depth of the damaged layer. The estimated depth information mapped on the image plane has resulted in a depth image which can display the shape of the defects as well as their depth simultaneously. An improved method introducing equivalent virtual heat sources that prevent the "boundary artifact" caused by the heat flux across the image boundary is presented.

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Various measurement methods using an ultrasonic sensor are generally used for inspecting the strength and reliability of actual structures. Therefore, there is a growing demand for developing accurate and precise ultrasonic sensing techniques. In this study, we aim to examine the precision of the ultrasonic sensing technique using a chirp burst pulse wave and a pulse compression methodology based on the leading edge technology of radar signal processing. In this paper, we present details of the pulse compression methodology, the analysis of the measured data, and the experimental results of the performance test of this method. The performance test demonstrated the plate thickness measurement under a series of experimental conditions. The results of the performance test, based on a comparison of the pulse compression method and conventional rectangle pulse emitted method, are as follows. (1) The effectiveness of pulse compression method is confirmed. (2) The pulse compression method enables high-precision measurement compared with the conventional rectangle pulse method.

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The objective of this study is the loosening detection of bolted joints without human involvement by applying the concept of structural health monitoring. The smart washer consists of the cantilever available to detect bolt loosening by using flexibility of cantilever and self-sensing/actuation function. The loosening is detected by the dynamics change of a smart washer system. This paper propose to apply the supervisor based on the modelbased FDI (Fault Detection and Isolation) technique for the detection of loosening by using multiple observer. The experimentations were performed to verify the possibility of the observer-based loosening detection. Improvement of loosening detection accuracy was confirmed by comparing the proposed to previous method.

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In this paper, a novel monitoring methodology to detect and characterize damages accompanied by changes in the micro/macroscopic condition of surface contact is proposed. The presented system consists of a PZT patch attached on the structural surface excited by a high frequency harmonic wave. When the structure is subjected to the operational or ambient load at low frequencies, it vibrates, and the inherent damages may introduce a nonlinear effect to the vibro-acoustic dynamics that induces an interaction between the low frequency structural vibration and the high frequency transmitted wave. This nonlinearity is observed as the modulation of the electric impedance of the PZT patch synchronous with the structural vibration. By investigating the relationship between the modulations and the structural vibration, the nonlinear characteristics of the damages can be specified. Experiments using a beam with low-cycle fatigue cracks are conducted for illustrative purpose.

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The oscillation of pipes containing two-phase flow is very important not only for the design of heat exchangers but also for the estimation of flow behavior by detecting the vibration or noise transferred from sounding rod pressed to the components. The skilled engineers sometimes can estimate the two-phase behavior with vibration or noise from components such as heat exchangers or steam generators. To understand the oscillation behavior and possibility to estimate the flow behavior, the air-water two-phase flow experiments were conducted with small vertical tubes of 2 and 11. 5mm in inner diameter. The oscillation of differential pressure was (DP) measured at the long observation span more than fifty times diameter to avoid the static pressure oscillation due the fluctuation of void fraction. The acceleration oscillation (WV) was also measured at several location of pipes. The root mean square (RMS) value of WV and DP was well correlated with Lockhart-Martinelli parameter. It was also demonstrated that the two-phase quality could be estimated with the proposed correlation for rms values when the liquid flow rate and RMS value were known.

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A great number of machine failures are caused by damage to bearings. However, since the damage mechanism of bearings is not well understood, conventional diagnostic methods have found difficulties in detecting damaged bearings at an early stage and further predicting bearing life. This study investigated such advanced diagnostic tools as the particle counting method of wear debris, hybrid sensor using combined monitoring of acoustic emission and vibration, and so on. These methods could to some extent provide early detection of damaged bearings, and the inside of those bearings was observed in detail to understand their possible damage mechanism.

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Milling is one of the most important metal cutting processes. If we measure the cutting force, we can make cutting process optimum, prevent tool breakage, and improve efficiency of process. Especially in the case of using an end mill with small diameter, it is very difficult to identify whether cutting process is good or not. In this paper, we proposed the cutting force measurement technique by using image processing. In the technique, we captured the image of the end mill during cutting process, determined the deflection of the tool and finally estimated the cutting force. Proposed technique can be applicable for any small size end mill and did not disturb the cutting process.

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Small fishing boats meet marine peril associated with engine damage on account of insufficient maintenance and aggressive operation in Japan. The failure diagnosis on reciprocal engine is more difficult than independent mechanical elements, because almost reciprocal engine is composed of great number of structural bodies and mechanical elements. Reciprocal engine find it hard to identify of failure elements to exist a number of noise sources within the engine. This paper experimentally examines the possibility of diagnose abnormal conditions about a four stroke twin cylinder reciprocal engine from generated vibration signals measured by accelerometers. Artificially assumed abnormal conditions in the reciprocal glow engine are concerning push rod driven rocker arm. Identification of above abnormal conditions has been carried out based on AR model constructed by normal vibration signal associated rotational frequency of the reciprocal glow engine. In conclusion, it is possible to diagnose above abnormal conditions even though differing degree of accuracy.

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In this research, picked up to the Joint of the Foot. As for foot joint, especially complex shape is had in the load joint that supports weight, and there are a lot of indistinct points in the mechanism. Recently, the number of foot joint syndromes by an acquired transformation increases. Especially, a flatfoot has a lot of patients as an acquired case. The bone in the arch of a normal foot and a flat foot was reproduced by three -dimensional model, the stress distribution was analyzed by the photoelastic investigation, and it made comparative study of them. The experiment analysis result showed the following things. It is calcaneus that change was looked at by especially stress distribution, and the stress value became high in the flat state outside in the normal condition at inside sidewall. If this will be in a flat state, it will be considered to be because for calcaneus to rotate inside.

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Major items of equipment of process plants are piping and heat exchangers. Their typical troubles with aging are mainly caused by scale adhesion and erosion-corrosion. The former decreases flow rate, pressure and heat transfer performance, the latter breaks piping and heat exchanger tubes. Therefore, the purpose of this study is to derive the diagnostic method of pipe thickness which is more effective than the monitoring pressure. In this paper, the diagnostic method of pipe thickness in water line is developed experimentally. It is based on the phase of the transfer function of low-side pressure to high-side pressure in the test section. The experimental results show that this diagnostic method is superior to monitoring pressure on detecting a changing pipe thickness.

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