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In comparison to other advanced economies, the rise of people living alone in Japan has been late and rapid, with singletons now accounting for almost half of all households in major cities. The normative and structural frameworks surrounding standard family-household formation, however, remain formidable, reducing life-course opportunities for non-family formers. This paper considers the household and housing pathways being negotiated by younger-adults living independently. In addition to various secondary data sources, we draw on qualitative interviews with 35 individuals from 28 Tokyo households in addressing manifestations of, and resistance to, atomisation and individualisation in the Japanese context. Our analysis focuses on meanings and practices of homemaking among renters and buyers in the growing sector of single-person dwellings, as well as the recent emergence of commercial shared housing . This analysis provides a contrast to discourses surrounding the “singles boom” and “the growing appeal of living alone” in Western cities.  相似文献   
2.
A distributed hydrological model (WaSiM-ETH) was applied to a mesoscale catchment to investigate natural flood management as a nonstructural approach to tackle flood risks from climate change. Peak flows were modelled using climate projections (UKCP09) combined with afforestation-based land-use change options. A significant increase in peak flows was modelled from climate change. Afforestation could reduce some of the increased flow, with greatest benefit from coniferous afforestation, especially replacing lowland farmland. Nevertheless, large-scale woodland expansion was required to maintain peak flows similar to present and beneficial effects were significantly reduced for larger “winter-type” extreme floods. Afforestation was also modelled to increase low-flow risks. Land-use scenarios showed catchment-scale trade-offs across multiple objectives meant “optimal” flood risk solutions were unlikely, especially for afforestation replacing lowland farmland. Hence, combined structural/nonstructural measures may be required in such situations, with integrated catchment management to synergize multiple objectives.  相似文献   
3.
The present paper, with reference to the Motru catchment area, contributes to the hydrochemical studies at an international level and to the completion of the characteristics regarding the chemical flow in Romania. In this regard, it emphasizes once again the dependence between the content of dissolved salts (fixed residue — mg/l) on the one hand and the lithological conditions, human activity, flow and the surface of the catchments on the other hand. The calculation and the analysis of the chemical flow for the Motru catchment area (located in the south-west of Romania) was performed on the basis of two parameters: the average flow of dissolved chemical substances (mg/s) and specific average chemical flow (t/kmp year) recorded at the monitoring stations on the Motru River and its tributaries during the period 2005–2009. The values obtained (for example: 2.63 mg/s and 47.7 t/km2 year, at the Fata Motrului station, on the Motru River, in 2009) confirm the importance of the areal factors of natural background in the analysis of chemical flow as a morpho-dynamic process and implicitly for the chemical quality of surface waters.  相似文献   
4.
This paper reports the first results on δ18O and δ2H analysis of precipitations, cave drip waters, and groundwaters from sites in Mallorca (Balearic Islands, western Mediterranean), a key region for paleoclimate studies. Understanding the isotopic variability and the sources of moisture in modern climate systems is required to develop speleothem isotope‐based climate reconstructions. The stable isotopic composition of precipitation was analysed in samples collected between March 2012 and March 2013. The values are in the range reported by GNIP Palma station. Based on these results, the local meteoric water line (LMWL) δ2H = 7.9 (±0.3) δ18O + 10.8 (±2.5) was derived, with slightly lower slope than Global Meteoric Water Line. The results help tracking two main sources of air masses affecting the study sites: rain events with the highest δ18O values (> ?5‰) originate over the Mediterranean Sea, whereas the more depleted samples (< ?8‰) are sourced in the North Atlantic region. The back trajectory analysis and deuterium excess values, ranging from 0.4 to 18.4‰, further support our findings. To assess the isotopic variation across the island, water samples from eight caves were collected. The δ18O values range between ?6.9 and ?1.6‰. With one exception (Artà), the isotopic composition of waters in caves located along the coast (Drac, Vallgornera, Cala Varques, Tancada, and Son Sant Martí) indicates Mediterranean‐sourced moisture masses. By contrast, the drip water δ18O values for inland caves (Campanet, ses Rates Pinyades) or developed under a thick (>50 m) limestone cap (Artà) exhibit more negative values. A well‐homogenized aquifer supplied by rainwaters of both origins is clearly indicated by groundwater δ18O values, which show to be within 2.4‰ of the unweighted arithmetic mean of ?7.4‰. Although limited, the isotopic data presented here constitute the baseline for future studies using speleothem δ18O records for western Mediterranean paleoclimate reconstructions. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
5.
Key in predicting stability in sands during dynamic events is gaining a fundamental understanding of the physics of its deformation and failure at high pressures. In this paper are reported results of an experimental investigation into the high‐pressure (up to 700 MPa) mechanical response of Quikrete sand. During all triaxial compression tests, the material exhibited hardening up to failure while both compressibility and dilatancy regimes of the volumetric response were observed. Furthermore, the transition from compressibility to dilatancy was found to be highly dependent on confining pressure. By performing triaxial compression tests with several creep stages followed by unloading–reloading cycles, the time influence of the overall response was detected. Using the experimental data, a new model that captures both compressibility and dilatancy has been developed. Comparison between model predictions and data showed that the proposed model describes well the main characteristics of the high‐pressure response of sand. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
6.
Volcanic gases from Showashinzan are qualitatively the same as those liberated from igneous rocks when they are heated in vacuum. Their main components are H2O, CO2, and H2. Then follow HCl, HF, N2, SO2, H2S, S, CH4, CO, Ar, Si, B, Mg, Na, K, Ca, Al, Fe, P, Br, NH3, As, Zn, Sr, Ba, Cu, Pb, Sn, Sb, Bi, Ge, Ag, Cr, Ni, Mo, Rn, Ra, etc. They come through fumaroles of high temperature (~750°C.). Metallic compounds deposit as sublimates around the outlet of fumaroles. They are fractionated there according to their thermodynamic properties. When the temperature of gases falls, heavy metal elements deposit before reaching the surface of the earth. Ra is among them. Owing to the contribution of Ra thus depositted, Rn content of vapor is larger in low temperature fumaroles than in high temperature ones. Chemical compounds of H, C, N, O, and S vary their composition according to the condition of temperature and pressure. Sulfur exists as SO2 more than H2S. As the temperature of gases falls, SO2 and H2 decrease and H2S increases. Mutual relation among them is ruled by the chemical equilibrium: SO2+3H2=H2S+2H2O. The structure of Showashinzan is not simple. Some deviations from the general rule are explained in connection with ground water.  相似文献   
7.
Current knowledge of caves and karst regions of Ecuador is scarce and broadly limited to discrete areas such as that of the Galápagos volcanokarst. In continental Ecuador, carbonate karst mostly outcrops in the Amazonian basin and accounts for 5–10% of the surface of the country. However, owing to the difficulties of access within the Amazonian rainforest, most surface and subterranean karst is yet to be revealed. In this review, we present an updated map of the solutional karst of Ecuador based on the most recent geological surveys and our own research. We describe the principal karst regions of Ecuador from the Amazonian basin (Napo and Santiago) as well as the Galápagos pseudokarst. We show that Ecuador karst research may be of considerable importance for both basic and applied research owing to its geographical position and intrinsic vulnerabilities. We discuss the main challenges of karst-related research in Ecuador, such as paleoclimatic studies, subterranean biodiversity, and archeology. We discuss the main vulnerabilities and hazards related to karst uses in Ecuador, considering the paramount importance of tourism for the country.  相似文献   
8.
The results of an experimental study aimed at characterizing the behavior of concrete for high confining pressures (up to 500 MPa) are reported. The main characteristics of the response under deviatoric conditions are quasi‐linearity in the elastic regime, stress‐path dependency, and gradual change from compressibility to dilatancy under increasing deviatoric stress. By performing the cyclic triaxial compression tests with several load–creep–unload and reload cycles, the time influence on the overall behavior was detected. Further, whether the main features of the observed behavior can be described within the framework of elastic/viscoplasticity theory was investigated. For this purpose, Cristescu's (Rock Rheology. Kluwer Academic Publishers: The Netherlands, 1989) approach was used. It was shown that the proposed elastic/viscoplastic model captures the main features of concrete behavior at high pressures. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
9.
A new model for calculating the resistance to penetration into geological or geologically derived materials is proposed. We assume steady‐state flow of the target material over the penetrator. The target medium is described by a rate dependent constitutive equation that accounts for combined effects of strain rate and compaction on yielding. The wedge‐shaped penetrator is considered to be rigid. The influence of the characteristics of the penetrator/target interface, impact velocity, target mechanical properties and nose geometry on the resistance to penetration is investigated. It is found that for low to intermediate impact velocities, accounting for friction results in a blunter optimal wedge geometry for optimal penetration performance. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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