Civil Engineering and Eco Technology Consultants Co.

Engineering, Japan

Civil Engineering and Eco Technology Consultants Co.

Engineering, Japan

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Tomita K.,Civil Engineering And Eco Technology Consultants Co. | Homma T.,Civil Engineering And Eco Technology Consultants Co. | Sumi T.,Kyoto University
River Sedimentation - Proceedings of the 13th International Symposium on River Sedimentation, ISRS 2016 | Year: 2017

Japan is characterized by steep mountain topography and weak geology as well as high precipitation and seasonal drastically changing temperature. As a result, sediment produced in mountain areas is frequently transported downstream and supplied to coastal areas through the river mouth which has formed many alluvial fans. In these upstream mountain rivers, many storage dams have been constructed for the purpose of flood control and water utilization. Nowadays, sediment accumulation in their active storage volume is a crucial issue both for reservoir and river basin sustainability. © 2017 Taylor & Francis Group, London.


Fujitani T.,Civil Engineering and Eco technology Consultants Co. | Kobayashi N.,Institute of River Biology | Hirowatari T.,Kyushu University | Tanida K.,Osaka Museum of Natural History
Limnology | Year: 2017

We associated imagoes and nymphs of four Nigrobaetis species from Japan and described their morphological characters. We found that N. sp. P comprised two Nigrobaetis species in Kanto Plain and in Ishigaki Island, which we described as N. apterus Fujitani n. sp. and N. ishigakiensis Fujitani n. sp., respectively. We also described N. sp. I as N. latus Fujitani n. sp. We recorded N. acinaciger (Kluge), the nymph of which had been confused with N. chocoratus (Gose), from Japan for the first time. We provide identification keys for eight Nigrobaetis species of Japan. © 2017 The Japanese Society of Limnology


Murakami T.,Nagoya Women's University | Hayashi Y.,Teruha Forest Association | Minami M.,Chubu University | Wang J.,CAS Institute of Tibetan Plateau Research | And 5 more authors.
Limnology | Year: 2012

We describe the limnological features of six glacier-fed rivers located at an altitude of over 4,000 m in Southern Tibetan Plateau, China, based on diurnal observations of the water environment and biota in the summer of 2010. The rivers showed significant diurnal changes in water level, temperature, and turbidity; clear and cool streams in the morning changed to cloudy rapid flow in the afternoon, and water temperature was elevated under strong light conditions where riparian forest did not cover the surface of the water. On the other hand, the pH and dissolved oxygen saturation did not show any diurnal fluctuations, which indicates low periphytic algal productivity. The aquatic insect communities were poor both in diversity and density, and the dominant life forms (from a functional feeding group perspective) were collectors, which depend on allochthonous organic matter; scrapers, which depend on autochthonous algal production, were scarce. We therefore suggest that diurnal or seasonal high waters transport products from marginal pools along dried riverbeds or from ponds on flood plains, and may serve as the source of organic matter in glacier-fed rivers. © 2012 The Japanese Society of Limnology.


Miyawaki S.,Civil Engineering and Eco Technology Consultants Co. | Washitani I.,University of Tokyo
Japanese Journal of Conservation Ecology | Year: 2010

Objective methods are needed for identifying areas where control measures against invasive alien species should be focused. We investigated classification tree models of the distribution of invasive plant stands (Ambrosia trifida, Eragrostis curvula, Sicyos angulatus, and Robinia pseudoacacia) in riparian areas of the Chikuma River. For each taxon, we used Classification And Regression Tree (CART) analyses to relate the distribution of invasive stands to explanatory variables (relative height from calculated water level, vegetation type, distance to nearest agricultural fields, areas dominated by the target species around each grid cell, and areas dominated by the target species in upstream river regions of each grid cell) and to derive the potential distribution of the target species. The current distribution of invasive stands along the Chikuma River was largely explained by relative height. We compared model predictions by testing the agreement between observed and simulated distributions (using the area under the receiver operating characteristic curve [AUC], specificity, sensitivity, and correct classification rate) by assessing consistency. Our results demonstrated that this modeling approach, combined with the visual presentation of predictions as a map, provides useful information for making decisions with regard to how different conservation actions and flood protection measures should be spatially allocated.


Fujitani T.,Civil Engineering and Eco technology Consultants Co. | Kobayashi N.,Institute of River Biology | Hirowatari T.,Osaka Prefecture University | Tanida K.,Osaka Prefecture University
Limnology | Year: 2011

We associated nymphs of three Tenuibaetis species with their imagoes by rearing. Herein we redescribe T. flexifemora and T. pseudofrequentus, and also provide description of a new species T. parvipterus. Tenuibaetis pseudofrequentus is morphologically similar to T. flexifemora in the imaginal stage, but we can distinguish these two species by the color patterns of their nymphs and their geographical distribution. Tenuibaetis parvipterus is distinguishable from the other two species by the fore femur, which is not bending distinctly, and abdominal sterna without distinct spots of male imago, reduced hind wing and abdominal sterna without distinct spots of female imago, and difference in color patterns of the abdomen of nymphs. Diagnostic characters of these species were tabulated. © 2011 The Japanese Society of Limnology.


Kunimatsu S.,Japan National Institute of Advanced Industrial Science and Technology | Kitamura Y.,Construction Engineering Research Institute Foundation | Yokota A.,Rion Co. | Uchida H.,Tobishima Corporation | And 6 more authors.
INTERNOISE 2014 - 43rd International Congress on Noise Control Engineering: Improving the World Through Noise Control | Year: 2014

In INCE/J, the prediction method of the first version of INCE/J RTV-Model named INCE/J RTV-Model 2003 for environmental impact assessment on ground-borne vibration induced by the road traffic was published for flat roads in 2003. Lvio (10 percentile-exceeded frequency weighted acceleration level) is used in the vibration evaluation for an environmental assessment in Japan. For this reason, the prediction in the model was based on a method to calculate the summation in decibel considering traffic volume within the defined time from the unit pattern which is the time history of vibration acceleration level at the prediction point when one vehicle runs on the road. The unit pattern could be calculated by using a simply empirical equation for the distance attenuation by Bornitz. In order to extend the previous model to a new applicable model for both cutting- And banking-structure roads, numerical simulations were performed. These results were summarized in this paper.


Kageyama Y.,Akita University | Takahashi J.,Akita University | Nishida M.,Akita University | Kobori B.,Civil Engineering and Eco Technology Consultants Co. | Nagamoto D.,Civil Engineering and Eco Technology Consultants Co.
IEEJ Transactions on Electrical and Electronic Engineering | Year: 2016

This letter reports on the water quality conditions of the Miharu Dam Reservoir. The water quality conditions appear in near-infrared (NIR) data collected by an unmanned aerial vehicle (UAV). Because blue-green algae occur in summer, the water quality of the small lake will be significantly worse at that time. On the basis of the experimental results for data from the months of July and August obtained using a fuzzy regression model, it is found that the UAV data is useful in assessing the water quality conditions in Lake Sakurako, and that the NIR data is effective in estimating the water surface conditions of the lake, especially caused by the occurrence of blue-green algae. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.


Shimura M.,Civil Engineering and Eco Technology Consultants Co. | Tateishi K.,Civil Engineering and Eco Technology Consultants Co. | Niwa H.,Civil Engineering and Eco Technology Consultants Co. | Nomura T.,Nihon University | And 3 more authors.
40th International Congress and Exposition on Noise Control Engineering 2011, INTER-NOISE 2011 | Year: 2011

Wind effect for low frequency sound measuring is one of the most important subjects on accurate sound evaluation at environmental outdoor site in natural wind. We have already proposed the wind noise estimation function as a previous work which was based on wind tunnel experiments, and suggested two dominant parameters; the mean wind velocity and the turbulence intensity in wind engineering definition. As a next step, we propose the new estimation function for low frequency wind noise in time dependent natural wind. Two dominant parameters are the same as wind tunnel experiments though wind evaluation time to calculate two parameters is under trial and discussion. In the present paper, we show the some cases about wind evaluation time comparing with out door measurements.


Iwabuki H.,Nippon Expressway Research Institute Co. | Osafune T.,Nippon Expressway Research Institute Co. | Shimura M.,Civil Engineering and Eco Technology Consultants Co. | Kamiakito N.,Civil Engineering and Eco Technology Consultants Co. | And 3 more authors.
42nd International Congress and Exposition on Noise Control Engineering 2013, INTER-NOISE 2013: Noise Control for Quality of Life | Year: 2013

The road complaints regarding noise, vibration and low frequency sounds have been delivered to the road and highway manager by residents living along the road. The countermeasure of road's noise and vibration depend on the generating source which define the construction work. Since, it may be difficult to determine the cause of low frequency sound, then, the generation mechanism should be considered. Therefore we tried the numerical simulation of low frequency sound field to estimate the response of a viaduct when vehicles run along track using three dimensional finite element method with unsteady analysis and non-stationary boundary condition. This method can be used to consider which part of the viaduct that largely generates low frequency sound. This paper introduces several cases that simulated by large-scale numerical model. Copyright © (2013) by Austrian Noise Abatement Association (OAL).


Goto A.,Hokkaido University | Goto A.,Hokkaido University of Education | Arioka H.,Hokkaido University | Yokoyama R.,Hokkaido University | Yokoyama R.,Civil Engineering and Eco Technology Consultants Co.
Environmental Biology of Fishes | Year: 2014

To elucidate the causes of clinal life-history variation in male freshwater amphidromous Cottus hangiongensis found along the river courses, we examined the genetic composition of upstream, midstream, and downstream groups using microsatellite DNA markers and different growth patterns among juvenile individuals before and after they ascended a small, steep mountainous river in southern Hokkaido, Japan. Microsatellite allele frequencies indicated that the samples collected from three different habitats appeared to represent a panmictic population and no genetic differences were found among the three groups. Ecological field surveys showed that juveniles greatly depended on the timing of their ascent into the river from the sea, and that larger juveniles were able to disperse to more upstream areas and grew larger during the period after they migrated up to the mouth of the river. These results suggested that clinal life-history variations may be induced through phenotypic plasticity and that earlier ascent of juveniles from the mouth of river may be an important source of variation. © 2013 The Author(s).

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