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Chiba, Japan

Chiba Institute of Technology is a private university in Narashino, Chiba, Japan. abbreviated as Chiba kōdai ,Chiba kō ,kōdai ,sen kōdai .The school was founded in 1942 in Machida, Tokyo. In 1946 it was relocated to Kimitsu, Chiba, adopted the present name at the same time. Four years later, it was moved to the present location. It is the oldest private technical university in Japan. Wikipedia.

Sugawara D.,Tohoku University | Goto K.,Chiba Institute of Technology
Sedimentary Geology | Year: 2012

This paper examines the results of a numerical modeling of the 2011 Tohoku-oki earthquake tsunami to investigate its offshore propagation and inundation along a shore-normal transect located in the center of the Sendai Plain. The inundation distance, flow depth, and flow speed were compared with the available data measured during a post-tsunami field survey and estimated from the video records. The calculated inundation distance reached 4.5-5.5. km from the coastline, which is comparable to the actual inundation distance. The variation of tsunami heights from 2.4-6. m and flow speeds from 3.4-6.2. m/s along the transect is generally consistent with the measured heights and estimated speeds. The waveform on the beach showed that the wave train was composed of a high (10-11. m) first wave followed by low (~. 4. m) waves. Considering the waveform and the topographic change, the erosion of the beach and the sedimentation inland are explained mainly by the first wave. In addition, the calculated flow speed and friction velocities in the offshore may account for the formation of the possible tsunami deposits, which were reported recently by a sea-bottom survey. The modeling results are generally consistent with the available data and are considered to be useful for understanding the inundation pattern and sedimentation process of the Tohoku-oki tsunami on the Sendai Plain. © 2012 Elsevier B.V.

Fujii K.,Chiba Institute of Technology
Journal of Earthquake Engineering | Year: 2011

The present article focuses on a nonlinear static procedure (NSP) for a multi-story asymmetric frame building with regular elevation subjected to bi-directional ground motion. In this procedure, two simplified models-an equivalent single-story model and an equivalent single-degree-of-freedom (SDOF) model-are used to predict the peak response of multi-story asymmetric buildings. The peak response is predicted through pushover analysis of an equivalent single-story model considering the effect of bi-directional excitations and an estimation of the nonlinear response of equivalent SDOF models. The predicted results are compared with the nonlinear dynamic analysis results, and satisfactory predictions can be obtained by the proposed procedure. Copyright © A. S. Elnashai & N. N. Ambraseys.

Kamino K.,Chiba Institute of Technology
Biofouling | Year: 2010

Balanomorphan barnacles attach their calcareous bases to a variety of substrata, including others of the same species, through secretion of an underwater adhesive, commonly referred to as cement. In this multi-functional process of underwater attachment, curing of the adhesive is crucial for the formation of a secure attachment. To date, there has been no direct evidence presented to suggest the involvement of cross-linking or polymerization in the cement curing process, despite the emergence of this hypothesis in the recent literature. A recently proposed mechanism for cement curing involves glutamyl-lysine cross-linking via the action of trans-glutaminase. However, in the opinion of the author, inadequate attention may have been paid to sample collection during the study and the conditions used in the analysis may not be adequate to support the conclusions of the paper. Indeed, further investigation, the results of which are presented here, did not provide any evidence to support adhesive curing via glutamyl-lysine cross-linking. Therefore, the hypothesis that the process of cement curing is similar to the clotting system of barnacle hemolymph is not compatible with the data reported so far. In order to allay any potential confusion, a new definition of the barnacle cement is proposed. © 2010 Taylor & Francis.

A simplified procedure is proposed to predict the largest peak seismic response of an asymmetric building to horizontal bi-directional ground motion, acting at an arbitrary angle of incidence. The main characteristics of the proposed procedure is as follows. (1) The properties of two independent equivalent single-degree-of-freedom models are determined according to the principal direction of the first modal response in each nonlinear stage, rather than according to the fixed axis based on the mode shape in the elastic stage; the principal direction of the first modal response in each nonlinear stage is determined based on pushover analysis results. (2) The bi-directional horizontal seismic input is simulated as identical spectra of the two horizontal components, and the contribution of each modal response is directly estimated based on the unidirectional response in the principal direction of each. (3) The drift demand at each frame is determined based on four pushover analyses considering the combination of bi-directional excitations. In the numerical example, nonlinear time-history analyses of six four-story torsionally stiff (TS) asymmetric buildings are carried out considering various directions of seismic inputs, and these results are compared with the predicted results. The results show that the proposed procedure satisfactorily predicts the largest peak response displacement at the flexible-side frame of a TS asymmetric building. © 2013 Springer Science+Business Media Dordrecht.

Saito T.,Chiba Institute of Technology
Journal of Alloys and Compounds | Year: 2010

The electrical resistivity and magnetic properties of Nd-Fe-B alloys produced by the melt-spinning technique were examined. The wheel speed, which is closely associated with the cooling rate, was varied in the production of the melt-spun ribbons. The resultant melt-spun ribbons had various microstructures ranging from dendrite to equiaxed grains, and finally to an amorphous structure, depending on the wheel speed. It was found that both the resistivity and coercivity of the melt-spun ribbons were strongly dependent on the wheel speed. The maximum resistivity of 3.15 μΩ m was achieved in a melt-spun ribbon primarily consisting of the amorphous phase with a small amount of the Nd 2Fe14B phase, while the highest coercivity of 1.97 MA/m was achieved in a melt-spun ribbon primarily consisting of the Nd 2Fe14B phase with a small amount of the amorphous phase. The relationships among the cooling rate, microstructure, resistivity, and coercivity of the Nd-Fe-B alloys were determined. © 2010 Elsevier B.V. All rights reserved.

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