The numerical simulation was carried out to discuss the effect of the ground stiffness on the vibrating behavior and running speed of the reversible vibratory plates. The result of the simulation made it clear that the running speed behaves two different ways under increasing of the ground stiffness. When the ground stiffness under the approx. 2.5 MN/m, the running speed of the reversible vibratory plates has correlation to the ground stiffness. When the ground stiffness over the approx. 2.5 MN/m, the running speed is stabilized to their own speed which is calculated with their mechanical factors. We studied the reason that the behavior of the running speed and suggested a method with which the weak point (low stiffness area) can be found out through the measuring running speed. The application of this method was examined in test pit experiments.

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 Civil engineering structures are central existence of social infrastructure. Maintenance management of civil engineering structures is important because they are designed to be used for a long time period and it is not avoided that the performance deterioration of them by change of the environmental condition which surround them or the use situation, etc. Since large amount of information is created in the maintenance management, it is necessary to record the process of creating information and to accumulate the information including the changes of degradation.
 Thus, we developed a process model to record the process of creating information about degradation and to manage information of degradation which changes in a long time period. In this paper, we described definitions of activities in process model, structures of process model, extension of schemas of IFC and examples of its application.

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 Because of the progress of informatization the accumulation and exchange of electronic information for roads has increased. Much of road information links positioning with map information. If we could share and cross organizations such information we could upgrade the existing information and create new services. One of the existing problems are the differentials in the maps coordinate data. This could cause position error between the sender and the receiver. Also there is the problem of the aging of the existing road network information and ID tagging.
 Our research will demonstrate a location referencing method named "Road Section Referencing with Road Section Identification Data set (RSIDs)" by using reference points within road sections. This paper will explain the definition, the result of creating the authority table all over the major road in Japan, and the result of the data exchanging experiments.

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 Verification about adaptability of an underground wireless communication system applying low frequency electro-magnetic wave, which has been developed for improving the efficiency during installation of transducers and stability of measurement, was carried out by monitoring test of pore water pressure at the existing rock fill dams. But, after five and half years, these were out of order and not able to perform data communication. The authors examined the reason they were out of order from the capacity test of their batteries and voltage data of batteries measured in site. From these results, it was clarified that capacity of its battery was sufficient but the voltage descent happened when the high electric current was required, for example, in a data communication procedure. Then the batteries were set in parallel to moderate the effect of voltage decent. Improved transducers were able to reduce the effect of voltage decent comparing with test models and perform correctly during six years after installed. Then it was verified the long term performance of a wireless transducer working by inner batteries depended on not only capacity of batteries but also voltage decent of them.

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 The orientation of images taken with a telecentric lens (TL) camera is discussed. For reverse engineering of small parts a TL camera have many advantages. It is characterized by orthonormal projection instead of central projection and by small lens distortions, which enables 3D measurement by photometric stereo, though distortion calibration is necessary for high precision measurement.
 This paper shows a process of orientation of multiple view images and discusses the resulting precision of object points coordinates and magnitude of distortions. Since the orthonormal projection holds, so-called factorization method can be applied to obtain initial values of unknowns for ensuing bundle adjustment. The estimated precision of image coordinates by bundle adjustment with no additional parameters is 0.44 pixels (3.3 μm) which corresponds to 11.4 μm in the object space. Self-calibrating bundle adjustment with inner orientation parameters, however, is shown not available, since high convergence exposures are not possible because of shallow depth of object field.

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 This paper proposes an inverse analysis method for estimating unobserved trigger factors according to different types of simultaneous slope failures. Through the structural equation modeling, Trigger Factor maps (termed "TF maps") produced by using causal factors (i. e., geographical information, remotely sensed data). Pointing out the limitations of pair-wise comparative strategy on the TF maps, a color composite map (i. e., Trigger Factor Influence map: TFI map) using TF maps are newly produced. The combination case of assigning the TF maps to RGB-color planes are determined based on an index of NCCT (Normalized Correlated Color Temperature) which represents the relationship between chromaticity and human visual perception. Through the cases examined, we have confirmed the proposed TFI map, as a heuristic visualization strategy, is effective for simultaneously evaluating the hazardous areas affected by the different types of slope failures.

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