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Journal of Water Resource and Protection 2016年第7期8卷 724-742页

作者： Toshisuke Maruyama manabu segawa Faculity of Environmental Science Ishikawa Prefectural University Ishikawa Japan

Evapotranspiration in forests has been researched for a long time because it serves an important role in water resource issues and biomass production. By applying the reciprocal analysis based on the Bowen ratio concept to the canopy surface, the sum result of sensible and latent heat fluxes, i.e., actual evapotranspiration (ET), is estimated from engineering aspect using the net radiation (Rn) and heat flux into the ground (G). The new method uses air temperature and humidity at a single height by determining the relative humidity (rehs) using the canopy temperature (Ts). The validity of the method is confirmed by the latent heat flux (lE) and sensible heat flux (H) observed by mean of eddy covariance method. The heat imbalance is corrected by multiple regression analysis. The temporal change of lE and H at the canopy surface is clarified using hourly and yearly data. Furthermore, the observed and estimated monthly evapotranspiration of the sites are compared. The research is conducted using hourly data and the validation of the method is conducted using observed covariance at five sites in the world using FLUXNET.

关键词： Bowen Ratio Eddy Covariance Reciprocal Determination Estimation of Evapotranspiration Canopy Surface Temperature and Humidity

Application of the Reciprocal Analysis for Sensible and Latent Heat Fluxes with Evapotranspiration at a Humid Region

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Open Journal of Modern Hydrology 2016年第4期6卷 230-252页

作者： Toshisuke Maruyama manabu segawa Faculty of Environmental Science Ishikawa Prefectural University Ishikawa Japan

Evapotranspiration acts an important role in hydrologic cycle and water resources planning. But the estimation issue still remains until nowadays. This research attempts to make clear this problem by the following way. In a humid region, by applying the Bowen ratio concept and optimum procedure on the soil surface, sensible and latent heat fluxes are estimated using net radiation (Rn) and heat flux into the ground (G). The method uses air temperature and humidity at a single height by reciprocally determining the soil surface temperature (Ts) and the relative humidity (rehs). This feature can be remarkably extended to the utilization. The validity of the method is confirmed by comparing of observed and estimated latent (lE) and sensible heat flux (H) using the eddy covariance method. The hourly change of the lE, H, Ts and rehs on the soil surface, yearly change of lE and H and relationship of estimated lE and H versus observed are clarified. Furthermore, monthly evapotranspiration is estimated from the lE. The research was conducted using hourly data of FLUXNET at a site of Japan, three sites of the United States and two sites of Europe in humid regions having over 1000 mm of annual precipitation.

关键词： Bowen Ratio Eddy Covariance Reciprocal Determination Estimation of Sensible and Latent Heat Fluxes Soil Surface Temperature and Humidity

Estimation of the Sensible and Latent Heat Fluxes by Reciprocal Analysis at an Arid and Semi-Arid Region

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Open Journal of Modern Hydrology 2017年第1期7卷 38-64页

作者： Toshisuke Maruyama manabu segawa Faculty of Environmental Science Ishikawa Prefectural University Ishikawa Japan

Sensible and latent heat flux at semi-arid and arid region, i.e., evapotranspiration, has been researched for long time because it serves an important role for water resource issues. However, the issues have not solved completely yet. Accordingly, by applying the Bowen ratio concept on the soil surface, the sensible and latent heat fluxes are reciprocally estimated using single height temperature (Tz) and humidity (rehz) with the net radiation (Rn) and heat flux into the ground (G). The procedure proposed by authors initially estimates the soil surface temperature (Ts) and the relative humidity (rehs) using optimization techniques. The method is remarkably effective to expand for estimating evapotranspiration at various regions. The validity of the method is confirmed by the latent heat flux (lE) and sensible heat flux (H) observed by the eddy covariance method. The hourly change of the lE, H, Ts and rehs on the soil surface, yearly change of lE and H and relationship of estimated lE and H versus observed are clarified. Yearly change of evapotranspiration is also estimated. The analysis is performed by general method (1), conventional method and general method (2). Above results are very useful for water resources issue and irrigation planning. The research is conducted using hourly data at eight globally dispersed sites using FLUXNET.

关键词： Bowen Ratio Eddy Covariance Evapotranspiration Optimization Single Height Temperature and Humidity

Estimation Accuracy for Reciprocal Analysis of Sensible and Latent Heat Flux Focusing on Radiometric Temperature and Lag-Time

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Open Journal of Modern Hydrology 2017年第2期7卷 105-124页

作者： Toshisuke Maruyama manabu segawa Faculty of Environmental Science Ishikawa Prefectural University Ishikawa Japan

There is no word to describe the importance of evapotranspiration research for water resource utilization. We have already proposed a new method for the reciprocal estimation of the sensible (H) and latent heat fluxes (lE) by using a single height temperature (Tz) and humidity (rehz) based on the observed net radiation (Rn) and ground heat flux (G). This research is more advanced than the previous research because it uses a Ts observed by a radiometer and identifies the observed data satisfactorily heat balance relationship in every hour at nine sites. First, we confirmed that the estimated H and lE are very close reproductions of the identified H and lE. Second, by analyzing the relative ground surface temperature (Ts - T0) [Ts: ground surface temperature, T0: observed temperature near the soil surface], the hourly and seasonal changes of (Ts - T0) were clarified, resulting in a marked difference in the (Ts - T0) from previous research in arid and semi-arid regions. Next, the estimation accuracy of H, lE and rehs (the humidity of the soil surface) was determined by observing the slope of the estimated and observed relationship, resulting in the reasonable accuracy (0.85 - 1.15 times) of rehs at seven of the nine sites. Furthermore, the annual evapotranspiration was estimated by comparing the identified and estimated H and lE, resulting in a reasonable accuracy (0.85 - 1.15) at five of the nine sites in the case of the application of constraint b. Moreover, the effect of the lag-time between the net radiation Rn and both Tz and Ts for the estimation accuracy on H and lE was tested, and no remarkable difference was found because the effect was included already in the original data. The above results will contribute greatly to the advance of water resource planning and hydrometeorology. This research was conducted using FLUXNET data.

关键词： Bowen Ratio Method Radiometric Temperature Lag-Time between Net Radiation and Temperature Single Height Temperature and Humidity Evapotranspiratio

Estimation of Unit Flood Discharge for Various Land Use Types with a Focus on Urbanization

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Open Journal of Modern Hydrology 2016年第4期6卷 195-211页

作者： manabu segawa Toshisuke Maruyama Keiji Takase Faculty of Environmental Science Ishikawa Prefectural University Ishikawa Japan

We proposed unit flood discharge model that defined as the discharge into end-order (smallest) drainage canals. The discharge acts an important role for estimating regional flooding by big rainfall events which leading roughly estimation of flood discharge associated with land use changes as urbanization. In some areas of Japan, increased urbanization with insufficient drainage canal capacity has led to increasingly frequent flooding and flood damage. The aim of this study was to investigate the effect of urbanization on unit flood discharge using a runoff model for the Tedori River alluvial fan area, Japan. The discharge was studied as collecting runoff from paddy fields, upland crop fields, and residential lots. A runoff model for various land use types in the study area was developed using actual and physical properties of the runoff sites, and parameters for paddy fields. The model was tested using 54 big events and inputted those. The maximum total runoff ratio among different land use types was observed for residential lots, and the ratio remained relatively constant across different flood events. The minimum total runoff ratio was observed for irrigated paddy fields. There was a positive relationship between the total runoff ratio and total precipitation for all land use types. Whereas, the relationship between the peak runoff ratio and peak precipitation was variable. The runoff analysis was carried out using 60-min and 10-min precipitation data. For agricultural land, data for both intervals produced similar results.

关键词： Unit Flood Discharge Total Runoff Ratio Peak Runoff Ratio Runoff Model Depression Storage

Flood Discharge Changes by Urbanization from Farmland Based on the Unit Flood Concept at the Kurabe River, Japan

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Open Journal of Modern Hydrology 2017年第3期7卷 223-243页

作者： manabu segawa Kouzo Ito Toshisuke Maruyama Faculty of Environmental Science Ishikawa Prefectural University Ishikawa Japan

Flood runoff models of urbanization from farmland based on the physical characteristics of a basin have been minimally used in previous research until today. Consequently, the runoff analysis has not been performed that is based on physical basis. Therefore, this research undertook flood discharge analysis from urbanization using the unit flood discharge concept that is enhanced the previous research. The study area was selected at the Kurabe River basin, which is 17.5 km2 in area having a very steep landscape. Twenty-one rainfall events at 10-minute intervals were selected, and five urbanized years were tested. From 1976 to 2009 during 35 years, the flood discharge increased approximately 2.0 times, in which residential areas increased from 23% to 48%;the maximum specific discharge was 21.7 m3·s-1·km-2 in a some block, which is a remarkably large amount. Furthermore, following issues investigated: changes in the hydrograph were associated with urbanization, the effect of a small reservoir aiming to cut down the peak discharge and the relationship between the unit discharge, and the relationship between our method and the discharge estimated by a “Rational Formula”. In particular, the effect of the small reservoir for flood control was found to be remarkably efficient. Finally, the validity of our method was confirmed at the study area in the observed discharge. This result is very useful for estimating runoff discharge changes by urbanization from farmland.

关键词： Unit Flood Discharge Kinematic Wave Method Flooding by Urbanization Specific Flood Discharge Lag Time

Effect of Flood Peak Discharge Control by a Small Reservoir in an Urbanized Area—Case Study in the Kurabe River Basin, Japan

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Open Journal of Modern Hydrology 2017年第4期7卷 314-330页

作者： Kouzo Ito manabu segawa Hiroshi Takimoto Toshisuke Maruyama Faculty of Environmental Science Ishikawa Prefectural University Ishikawa Japan

Recently severe damage of flooding by urbanization was frequently occurred. To prevent this damage, small reservoir was constructed in the urbanized residential area. This paper describes an effect of flood peak discharge control by a small reservoir (control reservoir) caused by rapidly developed urbanization. Although work for this purpose was conducted, research on the effects of the control reservoir was not conducted until now. This research, conducted by simulation, was a case study in the Kurabe River Basin in the Tedori River Alluvial Fan Area, Japan, based on the precise investigation of the reservoir in the actual field. The study was conducted to determine not only the actual control reservoir capacity for the newly developed residential area but also the ideal capacity for all present residential areas and the largest capacity allowable for a maximum rainfall event that recently occurred. The control reservoir effects between individual blocks and the entire basin area were compared by dividing the test basin into 15 blocks (sub-basins). The results showed that the effects on the capacity per unit area of the residential area in blocks have close relationship with the decreasing ratio of peak discharge in blocks. Consequently, the effects of control reservoir capacity and the limitation were clarified. In the future, control reservoirs should be constructed for all of the already developed residential areas, for example, by utilizing underground car parking lot. The results of this research can contribute to the design of the control reservoir for protection against flooding damage in urbanized areas.

关键词： Flood Control Reservoir Discharge from Urbanized Area Unit Flood Discharge Peak Discharge Decreasing Ratio Simulation of Drainage Discharge

The effect of the 18R-LPSO phase on the fatigue behavior of extruded Mg/LPSO two-phase alloy through a comparative experimental-numerical study

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Journal of Magnesium and Alloys 2021年第1期9卷 130-143页

作者： Fabien Briffod Takayuki Shiraiwa manabu Enoki Department of Materials Engineering The University of Tokyo7-3-1 HongoBunkyo-kuTokyo 113-8656Japan

The fatigue behavior of four extruded Mg-Y-Zn alloys containing different volume fractions of long-period stacking ordered(LPSO)grains was investigated through a comparative study combining experiments and crystal plasticity finite element *** controlled low-cycle fatigue experiments were conducted at different strain amplitudes and revealed a limited cyclic hardening in Mg_(89)Zn_(4)Y_(7)alloy or softening in Mg_(99.2)Zn_(0.2)Y_(0.6)and Mg_(97)Zn_(1)Y_(2)alloys.A decrease in the fatigue life against the plastic strain with the increase in LPSO phase volume fraction was observed and was related the limited ductility of extruded LPSO ***-strain hysteresis curves were used to calibrate and validate a crystal plasticity model taking into account twinning and *** interaction of the different phases on the distribution of local micro-mechanical fields at the grain scale was then analyzed on synthetic microstructures under strain-controlled *** twinning activity was predicted in coarse unrecrystallized grains and tended to disappear with the increase in the LPSO phase volume ***-like facets observed in LPSO grains were related to high tensile stress,especially at the Mg/LPSO interface,due to the limited number of deformation mechanisms in LPSO crystal to accommodate out-of-basal plane *** increase of the fatigue limit with the increase in LPSO phase volume fraction was finally associated with the decreasing presence of coarse unrecrystallizedα-Mg grains due to a higher dynamic recrystallization activity during the extrusion process.

关键词： Magnesium alloy Fatigue Long-period stacking ordered phase Crystal plasticity Finite element method

Effect of End Plates on the Performence of a Wells Turbine for Wave Energy Conversion

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Journal of Thermal Science 2006年第4期15卷 319-323页

作者： manabu Takao Toshiaki Setoguchi YoichiKinoue KenjiKaneko Department of Mechanical Engineering Matsue National College of Technology 14-4 Nishiikuma-choMatsue-shiShimane 690-8518Japan Institute of Ocean Energy Saga University1 Honjo-machiSaga-shiSaga 840-8502Japan Department of Mechanical Engineering Saga University1 Honjo-machiSaga-shiSaga 840-8502Japan

In order to improve the performance of the Wells turbine for wave energy conversion, the effect of end plates on the turbine characteristics has been investigated experimentally by model testing under steady flow conditions. The end plate attached to the tip of the original rotor blade is slightly larger than the original blade profile. The characteristics of the Wells turbine with end plates have been compared with those of the original Wells turbine, i.e., the turbine without end plate. As a result, it has been concluded that the characteristics of the Wells turbine with end plates are superior to those of the original Wells turbine and the characteristics are dependent on the size and position of end plate. Furthermore, the effect of annular plate on the turbine performance, which encircles the turbine and is attached to the tip, was investigated as an additional experiment. However, its device was not effective in improving the turbine characteristics.

关键词： fluid machinery natural energy Wells turbine end plate wave energy conversion ocean energy.

Cubic Spiral Transition Matching G^(2) Hermite End Conditions

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Numerical Mathematics(Theory,Methods and Applications) 2011年第4期4卷 525-536页

作者： Zulfiqar Habib manabu Sakai COMSATS Institute of Information Technology Department of Computer ScienceDefense RoadOff Raiwind RoadLahorePakistan Department of Mathematics&Computer Science Koorimoto 1-21-35Kagoshima 890-0065Japan

This paper explores the possibilities of very simple analysis on derivation of spiral regions for a single segment of cubic function matching positional,tangential,and curvature end *** are curves of monotone curvature with constant sign and have the potential advantage that the minimum and maximum curvature exists at their end ***,spirals are free from singularities,inflection points,and local curvature *** properties make the study of spiral segments an interesting problem both in practical and aesthetic applications,like highway or railway designing or the path planning of non-holonomic mobile *** main contribution is to simplify the procedure of existence methods while keeping it stable and providing flexile constraints for easy applications of spiral segments.

关键词： Path planning spiral cubic Bézier G2 Hermite Computer-Aided Design(CAD) computational geometry