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In this paper we give an axiomatization of differential geometry comparable to model categories for homotopy theory. Weil functors play a predominant role.

2012-11-07 08:31:04
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http://hdl.handle.net/2241/116677

1 0 0 0 OA Evaluation of slope stability by finite element method using observed displacement of landslide

著者: Ishii Yasuo Ota Keiichi Kuraoka Senro Tsunaki Ryosuke
出版者: Springer Verlag
雑誌: Landslides (ISSN:1612510X)
巻号頁・発行日: vol.9, no.3, pp.335-348, 2012-09
被引用文献数: 49

To monitor land deformation in detail, we ran a large-scale field test in which an artificial landslide was induced by the application of a load to a natural slope. The measured landslide displacement was reproduced numerically through the use of finite element model analysis with a two-dimensional elasto-viscoplastic model. The analysis suggested that the strength of the sliding surface decreased as the landslide mass moved. We propose a simple method for estimating safety factors. The method involves back-calculation of shear strength parameters through reproduction of observed landslide displacements and calculating the ratio of driving force to resisting force acting on the sliding surface as modeled by joint elements. This ratio, the “stability index”, shows the same trend as safety factors calculated by a two-dimensional limit equilibrium method and a shear strength reduction method that use back-calculated shear strength parameters estimated from the limit equilibrium state. The results indicate that the stability index may be applicable to the assessment of slope stability.

2012-11-07 08:30:58
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1 0 0 0 OA Study on the regulation of the functions of cultured animal cells by edible plant components

著者: 岩下恵子
巻号頁・発行日: 2001

Thesis (Ph. D. in Agriculture)--University of Tsukuba, (A), no. 2550, 2001.3.23

2012-11-07 08:30:52
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http://hdl.handle.net/2241/3883

1 0 0 0 OA 中高年2型糖尿病患者へのQOLを考慮した継続的教育方法に関する研究

著者: 板垣昭代
巻号頁・発行日: 2000

筑波大学博士 (医学) 学位論文・平成12年3月24日授与 (甲第2394号)

2012-11-07 08:30:41
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http://hdl.handle.net/2241/1467

1 0 0 0 OA Observation of ion diffusion in a velocity space induced by microinstability in a mirror plasma

著者: Goto Tetsuya
巻号頁・発行日: 2000

Thesis (Ph. D. in Science)--University of Tsukuba, (A), no. 2301, 2000.3.24

2012-11-07 08:30:36
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http://hdl.handle.net/2241/5481

1 0 0 0 OA Logicality of conditional term rewrite systems

著者: 山田俊行
巻号頁・発行日: 1999

Thesis (Ph. D. in Engineering)--University of Tsukuba, (A), no. 2125, 1999.3.25

2012-11-07 08:30:30
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http://hdl.handle.net/2241/2661

1 0 0 0 OA カイコ抗菌性ペプチド遺伝子の発現と構造解析

著者: 古川誠一
巻号頁・発行日: 1999

筑波大学博士 (農学) 学位論文・平成11年3月25日授与 (甲第2024号)

2012-11-07 08:30:19
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http://hdl.handle.net/2241/3971

1 0 0 0 OA Modeling the thermal and hydrological impacts of frozen ground on the climate system

著者: Takata Kumiko
巻号頁・発行日: 1998

The thermal and hydrological impacts of frozen ground in the climate system are investigated using an atmospheric general circulation model(AGCM)and a one-dimensional land-surface model. The AGCM experiments are performed with and without the soil freezing,i.e.,including and excluding the latent heat of fusion and impermeability of frozen soil. The inclusion of soil freezing leads to higher surface temperature in summer in mid-and high-latitudes over the land. This leads to larger water vapor fluxes and associated precipitation induced by stronger summer monsoons. The higher temperature over the land in summer results from the smaller evaporation caused by the smaller surface soil moisture.The small surface soil moisture is caused by the additional runoff in spring due to impermeability of frozen soils and the small available soil liquid water due to underlying frozen ground. The positive temperature anomaly is large in the regions where the potential evaporation is large even if the negative soil moisture anomaly is small,and vice versa.Moreover,the precipitation is smaller in the middle of the continent,owing to the smaller evaporation there. In winter,although the deep soil temperature in frozen ground ergions is figher with the soil freezing than without due to latent heat of fusion,the surface temperature anomaly is more likely to be governed by the atmospheric dynamical responses.Consequently,the frozen ground has the impacts on the continental scale climate.Nevertheless,the land-surface model used in the AGCM is so simple that the reproductivity of the land-surface processes and the magnitude of the frozen ground impact may be different with respect to the schemes and parameters of the soil model.Then sensitivity experiments using a one-dimensional land-surface model are performed. The effects of altering soil moisture flux schemes,adding the frozen soil permeability,adding the surface “ponding”and changing the snow infiltration parameter are examined. The atmospheric conditions are specified to the measurement data at three ststions in frozen ground regions of Russia. A sigle forcing is repeated until an equilibrated annual cycle is obtained. The equilibrinm,but that of soil moisture in permafrost,does not depend on the initial soil moisture. The initial soil moisture should,therefore,be carefully chosen when soil moisture in permafrost becomes a subject of discussion,e.g.,global warming. The freezing on thawing depth agrees with the measurements. It is however different by a few factors related to the soil moisture:the larger the soil moisture content is,the shallower the freezing or thawing depth is,since the larger soil moisture requires the larger latent heat fusion. The annual cycle of soil moisture is captured by the model. The inclusion of frozen soil permeability increases the infiltration in spring and autumn. The wet zones above the thaw front in spring and the water uptake towards the freezing front from unfrozen zones beneath in winter are also produced by including the permeability. These lead to the larger seasonal change in soil moisture that is closer to the measurements. The surface“ponding”increases the soil moisture in spring by holding snowmelt water. Changing the partial snow infiltration into the total infiltration also increases the soil moisture in spring.but its magnitude is smaller than the surface“ponding”effect. The combined effect of these two effects is sometimes not equal to the sum due to runoff processes. The differences in soil moisture change the annual heat and water budget at a considerable range. The frozen soil permeability and the surface“ponding”are fund to increase the annual evaporation. Finally,the sensitivity of the soil freezing impact to the parameterization is inverstigated using the one-dimensional model. The similar anomalies in summer are obtained as in the AGCM experiments,irrespective of the schemes and paramenters,although they may be reduced by considering the frozen soil permeability and the surface“ponding”. In conclusion.the frozen ground has continental scale impacts on the energy and water cycles. The measured soil moisture variations are reproduced better by considering the frozen soil permeability and the surface“ponding”. These also have effects on the annual heat and water budget. Further studies are needed to evaluate the surface“ponding”quantitatively against measurements,and to evaluate the model in a two-dimensional way,for example,using the river runoff data.

2012-11-07 08:30:14
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http://hdl.handle.net/2241/5323

1 0 0 0 OA Seasonal variations of sugars in atmospheric particulate matter from Gosan, Jeju Island: Significant contributions of airborne pollen and Asian dust in spring

著者: Fu Pingqing Kawamura Kimitaka Kobayashi Minoru Simoneit Bernd R. T.
出版者: Elsevier
雑誌: Atmospheric Environment (ISSN:13522310)
巻号頁・発行日: vol.55, pp.234-239, 2012-08
被引用文献数: 154

Sugars are important water-soluble organic constituents of atmospheric particulate matter (PM). In order to better understand the sources and seasonal variations of sugars in aerosols, primary saccharides (fructose, glucose, sucrose, and trehalose) and sugar alcohols (arabitol and mannitol), together with levoglucosan, have been studied in ambient aerosols at Gosan, Jeju Island in the western North Pacific, the downwind region of the Asian outflow, using gas chromatography-mass spectrometry. The results showed that the sugar composition varied seasonally with a total concentration range of 6.8-1760 ng m^[-3] (mean 246 ng m^[-3]). The total identified sugars had the highest concentration in April, the spring bloom season at Jeju Island, when sucrose contributed up to 80% of the total sugars. The dominance of sucrose was also detected in pollen samples, suggesting that pollen can contribute significantly to sucrose in aerosols during the spring bloom. The seasonal variation of trehalose is consistent with those of non-sea-salt Ca2+ and δ13C of total carbon with elevated levels during the Asian dust storm events. This study indicates that sugar compounds in atmospheric PM over East Asia can be derived from biomass burning, Asian dust, and primary biological aerosols such as fungal spores and pollen. Furthermore, this study supports the idea that sucrose could be used as a tracer for airborne pollen grains, and trehalose as a tracer for Asian dust outflow.

2012-11-07 02:36:17
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1 0 0 0 OA 明治期~大正期の秩父地域における絹織物生産発展の一側面

著者: 原田洋一郎
出版者: 筑波大学歴史・人類学系歴史地理学研究室
雑誌: 歴史地理学調査報告 (ISSN:09152504)
巻号頁・発行日: no.7, pp.75-87, 1996-03

2012-11-06 19:17:00
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http://hdl.handle.net/2241/105397