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Although the logistics industry provides critical services to all sectors of the economy, few studies exist in economic geography that examine and explain the organizational dynamics of this industry. This article highlights the significance of the logistics industry in contemporary industrialization and argues that an enriched understanding of the interaction between technology and space can be achieved by examining the evolution of an industry that plays a central role in the contemporary economy. We focus on dimensions that are identified as particularly important: organizational, geographic, and risk and security. 相似文献
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Keiichiro Fukazawa Tomoharu Aoyama Tatsuki Ogino Kiyohumi Yumoto 《Journal of Atmospheric and Solar》2010,72(13):1019-1023
It is well known that the cross polar cap potential is saturated under a strong interplanetary electric field and is often said to be related to the ionospheric currents. To investigate the other factors influencing this phenomenon, a global magnetohydrodynamics simulation not including the feedback from the ionosphere to the magnetosphere was conducted. The simulation results showed that an increase in the southward IMF causes a smaller increase in the cross polar cap potential than that caused by an increase in the solar wind velocity. This difference was caused by the transportation of reconnected magnetic field lines towards the tail. 相似文献
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Rock glaciers in the northern Japanese Alps: palaeoenvironmental implications since the Late Glacial
Masafumi Aoyama 《第四纪科学杂志》2005,20(5):471-484
In order to determine the palaeoclimatic and palaeo‐permafrost conditions in the northern Japanese Alps in central Japan, the ages of rock glaciers were investigated by relative age dating techniques such as weathering‐rind thickness and Schmidt hammer measurements. The results of the relative age dating suggest that the formation of the investigated rock glaciers may have started during the early phase of the Late Glacial or around the onset of the Holocene. The lower limit of current discontinuous permafrost in the northern Japanese Alps, which is indicated by the terminus of the lowest active/inactive rock glacier, lies at 2530 m a.s.l., while that of discontinuous permafrost during the Late Glacial or early phase of the Holocene, which is indicated by the terminus of the lowest relict rock glacier, lies at 2220 m a.s.l. Therefore, the lower limit of discontinuous permafrost during these periods would have been at least about 300 m lower than that of the current discontinuous permafrost. Climatic and geomorphological conditions during the Late Glacial led to a change in the environment from a glacial environment to a periglacial (permafrost) environment in the current alpine zone of the northern Japanese Alps. A large number of cirques were deglaciated and several of them were occupied by active rock glaciers around the onset of the Holocene. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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Recent studies reveal that R/C structural members subjected to biaxial flexure due to two-dimensional earthquake excitation can deform much more than would be predicted by conventional one-dimensional response analysis. The biaxial flexure may therefore have a significant effect on the dynamic collapse process of structures subjected to intense ground motions. The present paper is intended to develop a new formulation of the two-dimensional restoring force model of R/C columns acted upon by biaxial bending moments, and to discuss the dynamic response properties of R/C structures. The model considered is a two-dimensional extension of various non-linear models for one-dimensional response analysis, including the degrading trilinear stiffness model which is one of the simpler idealizations of the restoring force characteristics of flexural-failure-type R/C structures. The modelling validity is then examined by comparison with experimental data on the biaxial bending behaviour of R/C columns. Calculations are made to study the role of different system properties on the influence of inelastic biaxial bending on the dynamic structural response. It is shown that the inelastic biaxial effect is generally significant and, in some cases, critical in the case of R/C structures with stiffness-degrading properties, while the effect is not so important for the non-degrading inelastic cases. 相似文献
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Koichiro Doi Hideaki Hayakawa Takahito Kazama Toshihiro Higashi Shingo Osono Yoichi Fukuda Jun Nishijima Yuichi Aoyama Junichi Ueda 《极地研究(英文版)》2013,(4):339-343
Abstract This paper reports the results of field-based absolute gravity measurements aimed at detecting gravity change and crustal displacement caused by glacial isostatic adjustment. The project was initiated within the framework of the 53rd Japanese Antarctic Research Expedition （JARE53）. Absolute gravity measurements, together with GPS measurements, were planned at several outcrops along the Prince Olav Coast and S6ya Coast of East Antarctica, including at Syowa Station. Since the icebreaker Shirase （AGB 5003） was unable to moor alongside Syowa Station, operations were somewhat restricted during JARE53. However, despite this setback, we were able to complete measurements at two sites： Syowa Station and Langhovde. The absolute gravity value at the Syowa Station IAGBN （A） site, observed using an FG-5 absolute gravimeter （serial number 210; FG-5 #210）, was 982 524 322.7＋0.1 ktGal, and the gravity change rate at the beginning of 2012 was -0.26 gGal.a-1. An absolute gravity value of 982 535 584.2~0.7 ktGal was obtained using a portable A-10 absolute gravimeter （serial number 017; A-10 #017） at the newly located site AGS01 in Langhovde. 相似文献
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N-type earthquakes sometimes occur before the eruption of andesitic volcanoes, but their source mechanism has not been understood well. Their waveforms have stationary periods and decay slowly resembling to damped oscillation. They have common characteristics of spectra among the different stations; these spectral peaks appear at almost equal intervals of 1.0 Hz with common sharpness. We made detailed analysis on the N-type earthquakes observed at Asama volcano in July 1995. During 10 days activity, the duration of each earthquake increased gradually from 40 s to 3 min, while the peak frequency decreased from 2.7 to 0.8 Hz. Hypocenters are distributed slightly west under the summit crater with 0.4–1.7 km above sea-level. Source mechanism of the N-type earthquake is determined using a waveform inversion technique. Synthetic waveforms are calculated using 2D finite difference method. Surface topography is included in the calculation to incorporate the case that the source region is higher than the stations. Since the optimum solution has a large volumetric component, we approximated the volumetric part as a volume change of fluid filled sphere or cylinder or plane crack, and decomposed the solution into volumetric and non-volumetric part. Consequently, it is revealed that the optimum solution can be expressed as “crack expansion (contraction)+small fault slip”, because the spectral peak distribution advocates the crack expansion model among these three candidates. The frequency change during this activity may be explained by the time variation of the sound speed of inner fluid from 300 to 100 m/s. The change of the void fraction of water–steam phase might have caused the decrease of the sound speed. 相似文献
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Collapse mechanism of the Paleogene Sakurae cauldron, SW Japan 总被引：1，自引：0，他引：1
The Paleogene Sakurae cauldron of SW Japan is characterized by a nested structure with a polygonal outline (21×13 km2) including a circular collapsed part (5 km in diameter). Total thickness of the caldera infill amounts to 2,000 m. The lower member of the infill consists mainly of felsic crystal tuff and lesser intercalated andesitic lava flows, whereas the upper member is composed of high-grade ignimbrite capped with a large rhyolitic lava dome. These members represent the first and second stage eruptions, respectively. Faults bounding the cauldron rim comprise intersecting radial and concentric faults, producing the polygonal outline of this cauldron. The primary collapse of this cauldron thus occurred as a polygonal caldera basin where products of the first stage eruption accumulated. In contrast, the inner collapse part is defined by a ring fracture system. This sector subsided concurrently with accumulation of the high-grade ignimbrite of the second stage eruption. This inner circular collapse thus represents syn-eruptional subsidence concurrent with the climactic eruption. Magma drainage during the first stage probably induced outward-dipping ring fractures in the chamber roof. Opening of the ring fractures following subsidence of the central bell-jar block caused rapid evacuation of magma as voluminous pumice flows, even though magma pressure may have decreased to some degree. 相似文献
9.
Seasonal differences in catches of leptocephali in the East China Sea and Suruga Bay, Japan 总被引：2，自引：0，他引：2
Gen Minagawa Michael J. Miller Yobuo Kimura Shun Watanabe Akira Shinoda Jun Aoyama Katsumi Tsukamoto 《Estuarine, Coastal and Shelf Science》2007,71(3-4):730-740
The species composition, distribution, and size of eel larvae, or leptocephali, caught near the continental shelf in subtropical and temperate regions of East Asia were compared between two seasons (May–Jun and Oct–Dec) to learn about the seasonality of reproduction of marine eels. There was greater species richness and evidence of spawning by more species of marine eels during the late autumn surveys in both the East China Sea (ECS) and in Suruga Bay along the east coast of Japan. Small leptocephali <10 mm TL and a wide range of sizes of various taxa were collected during both seasons along the outer edge of the continental shelf in the ECS, indicating that some marine eels may spawn there all year. The lack of small leptocephali during the spring survey in Suruga Bay suggested that most eels have a clear seasonal cycle of summer or autumn spawning at the higher latitudes of coastal Japan where there is much greater fluctuation of water temperature throughout the year than in the ECS. At lower latitudes such as in the ECS, and in tropical areas where water temperatures are higher and more constant, some marine eels may spawn all year round. 相似文献