How meteorological disasters affect the labor market? The moderating effect of government emergency response policy

Natural Hazards - Natural disasters and climate change impose a severe threat to the sustainable development of economy and human society. This paper studies the economic consequences of...     

Statistical analyses and modeling approaches to hydrodynamic characteristics in alluvial aquifer

This study is aimed at quantifying the difference in aquifer's response to recharge between some different locations in a fan aquifer and a delta aquifer for a preliminary study of revealing mechanisms of water transport in alluvial aquifer. The aquifer's response to recharge is statistically quantified with the two viewpoints: (1) timing and volume of recharge and (2) time length of aquifer's holding water. For the first point, a statistical model that links precipitation and groundwater level is introduced, and its parameters are identified using correlation analysis. Our results show that the recharge rate at the toe is higher than that at the apex and at the delta. For the second point, the concept of ‘memory effect’ of aquifer is adopted and quantified using the autocorrelation and spectral analyses. Our results show that the memory effect is longer at the toe of fan than at the apex, and thus, a temporary increase of water level has about five times as long‐term influence on subsequent water levels at the toe of the fan as at the apex. This study demonstrates that the statistical analyses and modeling of hydrological data are useful for characterizing aquifer's hydrodynamics. Copyright © 2012 John Wiley & Sons, Ltd.     

Pressure‐temperature history of titanite‐bearing eclogite from the Western Iratsu body,Sanbagawa Metamorphic Belt,Japan

Evidence for eclogite‐facies metamorphism is widespread in the Western Iratsu body of the oceanic subduction type Sanbagawa Belt, Southwest Japan. Previous studies in this region focused on typical mafic eclogites and have revealed the presence of an early epidote‐amphibolite facies metamorphism overprinted by a phase of eclogite facies metamorphism. Ca‐rich and titanite‐bearing eclogite, which probably originated from a mixture of basaltic and calc‐siliceous sediments, is also relatively common in the Western Iratsu body, but there has been no detailed petrological study of this lithology. Detailed petrographic observations reveal the presence of a relic early epidote‐amphibolite facies metamorphism preserved in the cores of garnet and titanite in good agreement with studies of mafic eclogite in the area. Thermobarometric calculations for the eclogitic assemblage garnet + omphacite + epidote + quartz + titanite ± rutile ± phengite give peak‐P of 18.5–20.5 kbar at 525–565°C and subsequent peak‐T conditions of about 635°C at 14–16 kbar. This eclogite metamorphism initiated at about 445°C/11–15 kbar, implying a significantly lower thermal gradient than the earlier epidote‐amphibolite facies metamorphism (～650°C/12 kbar). These results define a P–T path with early counter‐clockwise and later clockwise trajectories. The overall P–T path may be related to two distinct phases in the tectono‐thermal evolution in the Sanbagawa subduction zone. The early counter‐clockwise path may record the inception of subduction. The later clockwise path is compatible with previously reported P–T paths from the other eclogitic bodies in the Sanbagawa Belt and supports the tectonic model that these eclogitic bodies were exhumed as a large‐scale coherent unit shortly before ridge subduction.     

Maximum seismic displacement of inelastic systems based on energy concept

The energy balance and energy input of Single-Degree-of-Freedom (SDF) systems under earthquake motion is studied for elastic and inelastic systems. The maximum displacement of an inelastic system is related to that of an elastic system having the same initial stiffness and mass by considering the earthquake energy input per cycle of oscillation. With an assumption that the cyclic energy input is equal for both elastic and inelastic system for intermediate- and long-period systems, a simplified relation is suggested. Newmark's equal energy rule is shown to be the upper bound of the simplified relation; the lower bound of maximum response displacement is also derived in this paper. The numerical analysis results were mostly shown to fall between the proposed upper and lower bounds. A separate approximate relation is proposed for short-period systems. The reason for divergence from the suggested relations is discussed for short-period systems. Copyright © 1999 John Wiley & Sons Ltd.     

Modeling strategy for jointed rock masses reinforced by rock bolts in tunneling practice

This paper deals with the modeling of jointed rock masses reinforced by rock bolts. It is well known that rock bolts are extremely effective in reinforcing jointed rocks. However, if a continuum approach is adopted for modeling jointed rock masses, it is often misleading to evaluate the effectiveness of the rock bolts by numerical analyses such as the finite element method. This may be due to the fact that since no more joints exist in the continuum, the effectiveness of the rock bolts in constraining the relative displacements along the joints cannot be evaluated properly. In order to investigate the reinforcement effect of rock bolts, physical model tests were performed in the laboratory. The test results revealed that jointed rock masses should be modeled as an equivalent continuum after the installation of rock bolts and that the mechanical parameters of the equivalent continuum should be evaluated by considering the reinforcement effect of the rock bolts. Therefore, the values of the mechanical parameters differ from place to place in accordance with the relation between joint orientation and rock bolt direction, even though joint systems are homogeneous. In conclusion, in the continuum approach for modeling jointed rock masses, it should be emphasized that rock bolts and jointed rock masses should not be modeled separately but should be modeled simultaneously by considering the reinforcement effect of the rock bolts in constraining joint movement. The modeling of shotcrete reinforced by steel ribs is also discussed in comparison to the modeling by rock bolts.     

Back analysis procedures for the interpretation of field measurements in geomechanics

A survey is presented of some recent developments of the numerical techniques for back analysis in the field of geomechanics, with particular reference to tunnelling problems. In the spirit of Terzaghi's observational design method, these techniques are seen as practical tools for interpreting the available field measurements, in order to reduce the uncertainties that in many instances affect the parameters governing the solution of complex geomechanics problems. Both deterministic and probabilistic viewpoints are considered and some significant applications to practical problems are illustrated.     

Better cars or older cars?: Assessing CO2 emission reduction potential of passenger vehicle replacement programs

The primary motivation for the vehicle replacement schemes that were implemented in many countries was to encourage the purchase of new cars. The basic assumption of these schemes was that these acquisitions would benefit both the economy and the environment as older and less fuel-efficient cars were scrapped and replaced with more fuel-efficient models. In this article, we present a new environmental impact assessment method for assessing the effectiveness of scrappage schemes for reducing CO₂ emissions taking into account the rebound effect, driving behavior for older versus new cars and entire lifecycle emissions for during the manufacturing processes of new cars. The assessment of the Japanese scrappage scheme shows that CO₂ emissions would only decrease if users of the scheme retained their new gasoline passenger vehicles for at least 4.7 years. When vehicle replacements were restricted to hybrid cars, the reduction in CO₂ achieved by the scheme would be 6–8.5 times higher than the emissions resulting from a scheme involving standard, gasoline passenger vehicles. Cost–benefit analysis, based on the emission reduction potential, showed that the scheme was very costly. Sensitivity analysis showed that the Japanese government failed to determine the optimum, or target, car age for scrapping old cars in the scheme. Specifically, scrapping cars aged 13 years and over did not maximize the environmental benefits of the scheme. Consequently, modifying this policy to include a reduction in new car subsidies, focused funding for fuel-efficient cars, and modifying the target car age, would increase environmental benefits.     

Gravity measurements with a portable absolute gravimeter A10 in Syowa Station and Langhovde,East Antarctica

Absolute gravity values were measured with a portable absolute gravimeter A10 in East Antarctica, for the first time by the Japanese Antarctic Research Expedition. This study aims to investigate regional spatiotemporal variations of ice mass distributions and associated crustal deformations around Syowa Station by means of repeated absolute gravity measurements, and we obtained the first absolute gravity value in Southern Langhovde on the Antarctic Continent. The average absolute gravity value at the newly installed benchmark AGS01 in Langhovde (obtained on 3 February 2012) was 982535584.2 ± 0.7 μgal (1 [μgal] = 1 × 10^?8 [m/s²]), which was in agreement with the gravity values obtained by the past relative gravity measurements within 1 mgal. In addition, the average absolute gravity value obtained at AGSaux in Syowa Station was consistent with both previous absolute gravity values and those obtained by simultaneous measurements using an FG5 gravimeter, owing to adequate data corrections associated with tidal effects and time variations in atomic clock frequencies. In order to detect the gravity changes associated with the ice mass changes and other tectonic phenomena, we plan to conduct absolute gravity measurements at AGS01 again and at other campaign sites around Syowa Station as well in the near future, with careful attention paid to the impacts of severe environmental conditions in Antarctica on gravity data collection.     

鲈鱼生长催乳素的分离纯化与N-末端序列分析

生长催乳素(SL)是生长激素/催乳素家族的一种新的脑垂体蛋白质激素,本研究首次从鲈鱼脑垂体中分离得到.鲈鱼脑垂体在碱性条件下,经葡聚糖凝胶(SephadexG-100)过滤和反相高效液相色谱(rpHPLC)分离出纯化的鲈鱼生长催乳素,(sbSL),并与大麻哈鱼生长催乳素(sSL)抗体发生特异性的Western免疫印迹交叉反应证实.SDS-聚丙烯酰胺凝胶电泳(SDS-PAGE)分析,发现鲈鱼生长催乳素分别是由分子量为23.2×103和28.4×103u两种形式组成(后者可能是一种糖基化形式).根据Edman降解原理,测得鲈鱼生长催乳素的N-末端16个氨基酸的序列,它与已知鱼类生长催乳素的N-末端序列比较,具有较高的同源性;由此进一步证实,分离纯化得到的鲈鱼生长催乳素是正确的.     

Historical Auroras in the 990s: Evidence of Great Magnetic Storms

A significant carbon-14 enhancement has recently been found in tree rings for the year 994, suggesting an extremely strong and brief cosmic ray flux event. The origin of this particular cosmic ray event has not been confirmed, but one possibility is that it might be of solar origin. Contemporary historical records of low-latitude auroras can be used as supporting evidence of intense solar activity around that time. We investigate previously reported as well as new records that have been found in contemporary observations from the 990s to determine potential auroras. Records of potential red auroras in late 992 and early 993 were found around the world, i.e. in the Korean Peninsula, Saxonian cities in modern Germany, and the Island of Ireland, suggesting the occurrence of an intense geomagnetic storm driven by solar activity.