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111.
Oman is a major recipient of South Asian labor immigrants, and correspondingly, the demographic statistics reveal that the non-Omani populations primarily are constituted of the Asians. This research examines whether the largest immigrant groups (Indian, Bangladesh, Pakistani and Sri Lankan) in Oman form residential clusters according to their work skills (higher and lower skills). The residential geographies of South Asian workers at the subnational administrative boundaries have been investigated in the current study. Empirically, the study employs the use of Location Quotients (LQ) and Entropy Index within the GIS environment to spatially analyze the immigrant residential distributions based on their work skills. Interestingly, the findings of this research confirm the primary influence of geography on the residential patterns of the low-skilled immigrants. Initially, Al-Batnah governorates constituted the main destinations of low-skilled Bangladeshis. Further, the research also highlights significant clusters of Indian and Pakistani high-skilled immigrants in urban residential communities within the Muscat governorate. In addition, the South Asian are found to be a relatively constant stream of immigrants to inhabit the Omani urban areas, with employments in various public and private economic sectors (e.g. educational, health, manufacturing, finance, business etc.). This concentration pattern of low skilled immigrants is attributable to the need to labor shortages of native populations in certain jobs. The research results also indicate that the rural and suburban communities of Al-Batnah coastal plain not only have a greater number of low skilled immigrants but also display equitable distributions of the four South Asian groups in the residential settlements. For policy makers, it is imperative to understand the spatial patterns of low and high-skilled immigrants in Oman, which exert several geographic, economic, social and demographic implications. The significant role of immigration in development necessitates the identification of the predominant destinations for immigrants. It has been observed that the immigrants are crucial to several sectors of Omani urban economy, and urban areas with a large number of immigrants are more likely to grow and expand faster. In addition, the immigrants’ laborers offer potential economic benefits to the host country, which include fostering entrepreneurial activities, small businesses and reducing wages, especially in unskilled jobs. Despite the negative impacts of immigration (e.g. losing national cultural and creating socio-spatial segregation), the diverse and distinctive locational patterns of immigrant groups in Oman contribute crucially to the socioeconomic development and immigration policy. Yet understanding of the spatial dynamics of immigration in structuring the Omani regions and its influences remains very limited. Thus, further research accounting for the different spatial and attribute ancillary data is necessitated. 相似文献
112.
喀斯特流域水系分形, 熵及其地貌意义 总被引:11,自引:3,他引:11
把分形理论和熵有机地结合起来,系统地研究了喀斯特流域和非喀斯特流域的干谷水系、常流水系和地下水系的分形结构及其熵的地貌意义,初步揭示了流域水系的形成与地貌发育演化之间的关系,认为仅利用水系的分维值来分析地貌演化是不够的,还应考虑流域水系的熵值变化. 相似文献
113.
EntropyofseawaveheightfieldanditsannualvariationinNorthwestPacificOceanSunFuandGuoPeifang(ReceivedOctober6,1995;acceptedOctob... 相似文献
114.
海浪波面的信息熵与海浪的谱宽度参量 总被引:6,自引:0,他引:6
将信息熵(InformationEntropy)引入到浪波面的研究,通过谱的参量化,建立了谱宽度参量P,R,ε^2,v^2与它们对应的信息熵之间的关系,这些谱宽度参量,皆可引人到波面与波高的分布函数之中,并指出谱宽度参量具有熵的含义,给出了海浪波面熵的一种合理表示。 相似文献
115.
Katja Etzel Artur Benisek Edgar Dachs Lado Cemič 《Physics and Chemistry of Minerals》2007,34(10):733-746
The unite cell parameters and heat capacities of a series of synthetic clinopyroxenes on the join Ca-Tschermak (CaTs)−diopside
(Di) were measured using X-ray powder diffraction and calorimetric methods, respectively. The volume of mixing at 298 K shows
a negative asymmetric deviation from ideality. A two-parameter Margules fit to the data yields W
CaTs−Di
V
= −0.29 ± 0.11 cm3 mol−1 and W
Di−CaTs
V
= −1.14 ± 0.14 cm3 mol−1. Heat capacities were determined between 5 and 923 K by heat-pulse at 5−302 K and differential-scanning calorimetry at 143−923 K.
The precision of the low and high temperature C
p
data is better than ±1%. Polynomials of the form C
p
= a + bT
−1/2 + cT
−2 + dT
−3 were fitted to the C
p
data in the temperature range between 250 and 925 K. Thermal entropy values [S
298 − S
0] and [S
900 −S
0] as well as enthalpies [H
298 − H
0] and [H
900 − H
0] were calculated for all members of the solid solution series. No significant deviation from ideal mixing behavior was observed. 相似文献
116.
Vijay P. SINGH 《国际泥沙研究》2003,18(3)
Hydraulic geometry is of fundamental importance in planning, design, and management of river engineering and training works. Although some concepts of hydraulic geometry were proposed toward the end of the nineteenth century, the real impetus toward formulating a theory of hydraulic geometry was provided by the work of Leopold and Maddock (1953). A number of theories have since been proposed. Some of the theories are interrelated but others are based on quite different principles. All theories, however, assume that the river flow is steady and uniform and the river tends to attain a state of equilibrium or quasi-equilibrium. The differences are due to the differences in hydraulic mechanisms that the theories employ to explain the attainment of equilibrium by the river. 相似文献
117.
118.
119.
120.
M. Akaogi H. Kojitani T. Morita H. Kawaji T. Atake 《Physics and Chemistry of Minerals》2008,35(5):287-297
Low-temperature isobaric heat capacities (C
p
) of MgSiO3 ilmenite and perovskite were measured in the temperature range of 1.9–302.4 K with a thermal relaxation method using the
Physical Properties Measurement System. The measured C
p
of perovskite was higher than that of ilmenite in the whole temperature range studied. From the measured C
p
, standard entropies at 298.15 K of MgSiO3 ilmenite and perovskite were determined to be 53.7 ± 0.4 and 57.9 ± 0.3 J/mol K, respectively. The positive entropy change
(4.2 ± 0.5 J/mol K) of the ilmenite–perovskite transition in MgSiO3 is compatible with structural change across the transition in which coordination of Mg atoms is changed from sixfold to eightfold.
Calculation of the ilmenite–perovskite transition boundary using the measured entropies and published enthalpy data gives
an equilibrium transition boundary at about 20–23 GPa at 1,000–2,000 K with a Clapeyron slope of −2.4 ± 0.4 MPa/K at 1,600 K.
The calculated boundary is almost consistent within the errors with those determined by high-pressure high-temperature in
situ X-ray diffraction experiments. 相似文献