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1.
In this study, households’ decisions on reconstruction of damaged houses were modeled, using questionnaire data in Japan. Characteristics of households’ decisions were investigated using parameter estimation results. The effects of subsidizing policy were evaluated as follows. First, subsidy for rebuilding may be effective for the households whose houses were heavily damaged. Second, there is a possibility that subsidy accelerated rebuilding of houses by the households having children. Third, subsidy for rebuilding may not be effective for elderly people’s households and households in depopulated areas.  相似文献   
2.
The photo-inhibition of phytoplankton photosynthesis at higher intensities was examined with a cultured marine diatom,Phaeodactylum tricornutum, and natural samples. The question was to determine whether photo-inhibition results from excretion of photosynthetic products from cell or from an actual decrease in photosynthetic rate. P. tricornutum cultured at 15 klux showed very little photo-inhibition up to 70 klux, and, in the sample cultured at 1 klux, most marked photo-inhibition was observed in 3 hours experiment. Extracellular release was less than 30% of particulate fixation, and did not show any extreme increase to supplement photosynthesis depression at higher light intensities. When the photosynthesis was measured during 10 minutes, both samples showed no photo-inhibition. The photosynthesis by low light sample lost the linearity of time-course with prolonged exposure at high light intensity. Observed photo-inhibition, therefore, we explained with the actual decrease in photosynthetic rate. Similar photo-inhibition could be seen in marine phytoplankton samples concentrated by filtration.  相似文献   
3.
Water plumes, 20 km long or less, identified by low temperature, high salinity and high nutrient concentrations, were observed on the eastern side of Izu Islands where the Kuroshio Current or its branch flowed eastward. The T-S diagrams and the vertical profiles of oceanographic variables indicated that the water plumes resulted from the upwelling of subsurface water. A newly formed plume, characterized by a sharp temperature front and high nutrient concentrations, contained less chlorophyll than did old plumes. It is suggested that the upwelling plumes are maintained for a period long enough to allow luxuriant growth of phytoplankton.  相似文献   
4.
The Building Standard Law of Japan and related Enforcement Order and Notifications have been substantially revised since the year 2000 to introduce a performance-based regulatory and deregulation system for building control systems. Up to then, time-history analyses were mandatory for isolated buildings and had to be specially approved by the Minster of the Ministry of Construction (MOC). Simplified design procedures based on the equivalent linear method for seismically isolated buildings have been issued as “Notification 2009 — Structural calculation procedure for buildings with seismic isolation” from MOC, and are now integrated into the Ministry of Land, Infrastructure, and Transportation (MLIT). Along with Notification 2009, “Notification 1446 of year 2000 — Standard for specifications and test methods for seismic isolation devices” was also issued. Buildings with heights equal to or less than 60m and that are designed according to these Notifications, including base isolated buildings, only need approval from local building officials, and no longer require the special approval of the Minister of MLIT. This paper summarizes: 1) some statistics related to buildings with seismic isolation completed up to the end of 2001; 2) simplified design procedures required by Notification 2009 of year 2000; and 3) performance of seismic isolation devices required by Notification 1446 of year 2000.  相似文献   
5.
Horie  Kei  Maki  Norio  Kohiyama  Masayuki  Lu  Hengjian  Tanaka  Satoshi  Hashitera  Shin  Shigekawa  Kishie  Hayashi  Haruo 《Natural Hazards》2003,29(3):341-370
Rebuilding of victims' livelihoods was a crucial issue in the restoration process in the1995 Hanshin-Awaji Earthquake Disaster. Housing damage assessment influencedmost of the rebuilding of the livelihood in the long term, because the Victim Certificatesissued by the local governments based on the results of the Housing damage assessmentwas required to receive most of the individual assistance measures. In the process ofHousing damage assessment, many complex problems arose, leading to extensivework on the part of the disaster responders. Consequently, a considerable number ofvictims were dissatisfied with the assessment and applied for a resurvey. Due to a floodof requests for resurvey, disaster responders had to work on damage assessment, leavingrelief activities aside.In order to facilitate Housing damage assessment, this paper discusses thefollowing five points: (1) the processes and the problems of assessments performedin the Hanshin-Awaji Earthquake Disaster, (2) the changes in the nature of informationneeded by the victims, (3) the improvements over the present damage assessment, (4)the housing situation in Japan, and (5) the international situation on damage assessment.It is obvious from the results that a poor damage assessment system and the size ofthe disaster produced a very large work load. Differences in appreciation among theinvestigators also contributed to unfair assessments and led to the victims beingincreasingly dissatisfied by the survey results. Finally, a design concept for acomprehensive damage assessment system, which has been derived from theabove five points, is proposed for post-disaster management.  相似文献   
6.
 The Middle Miocene Tobe hornfels in the Sanbagawa metamorphic belt, western Shikoku, southwest Japan, is characterized by an abnormally steep metamorphic gradient compared with other hornfelses associated with intrusive bodies. The basic hornfels, originally Sanbagawa greenschist rocks, is divided into the following three metamorphic zones: plagioclase, hornblende, and orthopyroxene. The plagioclase zone is defined by the appearance of calcic plagioclase, the hornblende zone by the assemblage of hornblende+calcic plagioclase+quartz, and the orthopyroxene zone is characterized by the assemblage of orthopyroxene + clinopyroxene + plagioclase + quartz. Calcic amphibole compositions change from actinolite to hornblende as a result of the continuous reactions during prograde metamorphism. Petrographical and thermometric studies indicate a metamorphic temperature range of 300–475°C for the plagioclase zone, 475–680°C for the hornblende zone, and 680–730°C for the orthopyroxene zone. The temperature gradient based on petrological studies is approximately 5°C/m, which is unusually high. Geological and petrological studies demonstrate that the hornfelses were formed by the focusing of high-temperature fluids through zones of relatively high fracture permeability. The steep thermal gradient in the Tobe hornfels body is consistent with a large fluid flux, greater than 8.3 × 10–7 m3 m–2S–1, over the relatively short duration of metamorphism, approximately 100 years. Received: 10 October 1995 / Accepted: 28 May 1996  相似文献   
7.
8.
Chemical compositions of materials used for new sample holders (vertically aligned carbon nanotubes [VACNTs] and polyimide film), which were developed for the analysis of Hayabusa2‐return samples, were determined by instrumental neutron activation analysis and/or instrumental photon activation analysis, to estimate contamination effects from the sample holders. The synthetic quartz plate used for the sample holders was also analyzed. Ten elements (Na, Al, Cr, Mn, Fe, Ni, Eu, W, Au, and Th) and 14 elements (Na, Al, K, Sc, Ti, Cr, Zn, Ga, Br, Sb, La, Eu, Ir, and Au) could be detected in the VACNTs and polyimide film, respectively. The VACNT data show that contamination by this material with respect to the Murchison meteorite is negligible in terms of the elemental ratios (e.g., Fe/Mn, Na/Al, and Mn/Cr) used for the classification of meteorites due to the extremely low density of VACNTs. However, for the Au/Cr ratio, even small degrees (1.7 wt%) of contamination by VACNTs will change the Au/Cr ratio. Elemental ratios used for the classification of meteorites are only influenced by large amounts of contamination (>60 wt%) of polyimide film, which is unlikely to occur. In contrast, detectable effects on Ti isotopic compositions are caused by >0.1 and >0.3 wt% contamination by VACNTs and polyimide film, respectively, and Hf isotopic changes are caused by >0.1 wt% contamination by VACNTs. The new sample holders (VACNTs and polyimide film) are suitable for chemical classification of Hayabusa2‐return samples, because of their ease of use, applicability to multiple analytical instruments, and low contamination levels for most elements.  相似文献   
9.
We observed tidal currents, turbulent energy dissipation and water column stratification at the entrance of a narrow strait (Neko Seto) in the Seto Inland Sea, Japan, using a free-falling turbulent microstructure profiler (TurboMAP) and acoustic Doppler current profiler (ADCP). The variation in turbulent energy dissipation at the entrance of the strait was not at quarter-diurnal frequency but at semi-diurnal frequency; turbulent energy dissipation was enhanced during the ebb tide, although it was moderate during the flood tide. This result is consistent with the results of Takasugi (1993), which showed the asymmetry of tidal energy loss during a semidiurnal tidal cycle using control volume analysis. It is suggested that significant turbulent energy dissipation is generated in the strait, which influences the properties of water outside the strait when tidal currents flow out from the strait.  相似文献   
10.
Mean total length of the eldest cohort (MTLe) of the thalassinidean decapod, Upogebia yokoyai sampled at 16 sites showed a latitudinal variation from south-west islands of the Ryukyu Archipelago (24° N) to the Seto-Inland Sea of Japan (34° N). Local variations were however also found from sites in the same latitudes. The level of the organic content in each habitat showed a positive correlation with MTLe. We hypothesized that MTLe is strongly affected by the trophic condition, resulting in the local variations. To test this hypothesis, two estuaries with different organic content were compared; Kodono River (Kochi Prefecture, 33° N) which was relatively oligotrophic and Sakata River (Hiroshima Prefecture, 34° N) which was highly eutrophicated. The Kodono River population showed slow growth after settlement, and growth stopped in May to June. This population survived for only one or two years, resulting in small MTLe. On the other hand, the Sakata River population showed fast growth from August to December. This population survived for three years, resulting in large MTLe. Maturation was estimated to occur two years after settlement in both populations. Low salinities may partially affect MTLe. Habitats in the Seto-Inland Sea (33.5–34.8° N) were eutrophicated, but many habitats in the subtropical islands (24–31° N) were relatively oligotrophic. Latitudinal variation of MTLe was reflected by the geographical difference in trophic condition. A negative relationship between population density and growth was found, which was explained in terms of reduced survival of recruits in the eutrophicated habitats.  相似文献   
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