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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.

Murakami T.,Nagoya Womens 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.

Kamiakito N.,Civil Engineering and Eco Technology Consultants Co. | Shimura M.,Civil Engineering and Eco Technology Consultants Co. | Aoki A.,Civil Engineering and Eco Technology Consultants Co. | Tateishi K.,Civil Engineering and Eco Technology Consultants Co. | And 9 more authors.
41st International Congress and Exposition on Noise Control Engineering 2012, INTER-NOISE 2012 | Year: 2012

It is well known that the outdoor measurement of low frequency sound is affected very much by the surrounding natural wind. Low frequency sound should be measured when there is no wind. But actually there are cases that we must measure even if the wind is blowing. We'd like to be able to distinguish the wind noise effect appropriately and to measure low frequency sound. We have investigated the method to evaluate wind noise effects by the regression function. As the previous work, the definition of wind noise was shown, and wind tunnel test and outdoor experiment were conducted as written in the previous papers1,2,3. And we made it clear that the wind noise was affected by frequency of sound, turbulence intensity and mean wind velocity. In the present paper, we present two regression functions by natural wind based on the sound measurement at outdoor sites which were different roughness classes. In addition, we targeted low frequency sound caused by a viaduct of expressway for the evaluation, and we tried the estimation of wind noise effect using the regression function.

Kunimatsu S.,Japan National Institute of Advanced Industrial Science and Technology | Kitamura Y.,Construction Engineering Research Institute Foundation | Uchida H.,TOBISHIMA Corporation | Shimura M.,Civil Engineering and Eco Technology Consultants Co. | And 5 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.

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.

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