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Sunyong Eom Tsutomu Suzuki Myeong-Hun Lee 《International journal of geographical information science》2020,34(5):899-923
ABSTRACT Land-Use Mix (LUM) refers to the strategy of integrating complementary functions within a building or area. While LUM has become a dominant approach in urban planning, its actual benefits and vision for spatial planning remain unclear. To clarify this issue, this study discerns the spatial features of land-use patterns depending on the compatibilities among land-use categories. Accordingly, this study introduces three LUM measures – adjacency, intensity, and proximity – to identify differences in the spatial distribution of land-use categories. Based on these measures, a land-use allocation model is developed to specify spatial patterns satisfying the given compatibilities. This model is tested by applying the concept of the neighborhood unit on a case study of normative land-use patterns subject to specified compatibilities. The results describe spatial features of four compatibility sets, including a set exhibiting a compatibility conflict between the same land-use pair and LUM measures when, for example, a given land-use pair is compatible in terms of intensity but incompatible in terms of proximity. Understanding the spatial features of a normative land-use pattern that satisfies various possible compatibilities will facilitate the incorporation of the LUM approach into local planning guidance and zoning ordinances. 相似文献
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This paper presents a method that incorporates a non‐associated flow rule into the limit analysis to investigate the influence of the dilatancy angle on the factor of safety for the slope stability analysis. The proposed method retain's the advantage of the upper bound method, which is simple and has no stress involvement in the calculation of the energy dissipation and the factor of safety. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Viviane Pierrard Milan Maksimovic Joseph Lemaire 《Astrophysics and Space Science》2001,277(1-2):195-200
Electron velocity distribution functions (VDF) observed in the low speed solar wind flow are generally characterized by ‘core’
and ‘halo’ electrons. In the high speed solar wind, a third population of ‘strahl’ electrons is generally observed. New collisional
models based on the solution of the Fokker-Planck equation can be used to determine the importance of the different electron
populations as a function of the radial distance. Typical electron velocity distribution functions observed at 1 AU from the
Sun are used as boundary conditions for the high speed solar wind and for the low speed solar wind. Taking into account the
effects of external forces and Coulomb collisions with a background plasma, suprathermal tails are found to be present in
the electron VDF at low altitudes in the corona when they exist at large radial distances.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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We show how the Yarkovsky effect can be understood as a heat engine. The output of the engine, manifested in the rate of change in semimajor axis of the body, has a maximum at an intermediate heat capacity, depending on the rotation rate of the body. This maximum arises because the work output depends on the product of the solar heat absorbed by the body and transported from its morning to evening side (this am-pm heat flux increases with heat capacity) and the Carnot efficiency (which declines with heat capacity). 相似文献