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61.
The post-Independence period in India has witnessed a gradual decline of some occupations and services and the emergence of others. In the present paper an attempt has been made to analyze the change in the industrial structure of India's male working force by calculating an index of change. The index so calculated for 2 decades separately (1961-1971 and 1971-1981) is portrayed cartographically. The overall low degree of change recorded by the country's male working force establishes the weakness of India's industrial infrastructure. Consequently, the secondary sector seems to have failed in generating employment opportunities on a large scale. Regionally, the peripheral areas have recorded a higher incidence of change than the interior heartland of the country. The areas that were overwhelmingly agricultural and had experienced developments in the field of agriculture alone exhibited a low degree of change in comparison to those that had experienced developments both in the field of agriculture and industry. During the last inter-censal period (1971-1981) the country recorded an accelerated rate of change in the industrial structure of its male working force. Spatially too, the increasing rate of change has spread to new regions.  相似文献   
62.
To understand the effect of climate change on constitutive antioxidant and biochemical metabolites in Western Himalayas, five medicinal herbs were selected and grown at two altitudes in Jammu (305 m) and Srinagar (1730 m) with subtropical and temperate climates, respectively. Significant variations were observed in phenols and flavonoids in Hypericum perforatum L., Matricaria chamomilla L., Thymus vulgaris L., Cynara cardunculus L. and Echinacea purpurea L. growing at two locations. High altitude temperate site show variable (up to 13 fold) increase in their content. Proteins (1.3 – 1.8 times), sugars (2.8 – 4.1 times) and free amino acid (1.04 – 1.22 times) were also higher at Srinagar (1730 m). Within these plants, H. perforatum and M. chamomilla have shown higher accumulation of phenols, xanthophylls and proline even at subtropical environment in Jammu (305 m) suggesting potential for increasing their geographical area. The results demonstrate that changing environmental conditions significantly affect the bioactive constituents, which accumulate as a defence strategy by these temperate plants. Their medicinal significance during climate change scenario has also been discussed.  相似文献   
63.
Flood hazards are the most destructive among all natural disasters and are a constant threat to human’s life and property. Effective disaster risk reduction strategies can be improved by geospatial approach in the way of producing information and knowledge that are useful to plan truly effective actions for the protection from floods. This research aims to develop a quantified predictive model of flood susceptibility in the Ghatal and Tamluk subdivision of Medinipur district of West Bengal, India, by means of empirically selected and weighted spatial predictors of flood. The weighted prediction model is used to quantify the spatial associations between individual geospatial factors within the flood inundated study area. Yule’s coefficient and distance distribution analysis are used to assign weights to individual geo-factors, and finally weighted spatial predictors are integrated to a multi-class index overlay analysis to derive the spatially explicit predictive model of flood susceptibility. The resultant susceptibility model reveals that approximately 32.35 and 52.99% of the total study areas (3261.45 km2) are under the category of high-to-moderate flood susceptible zone. Quantitative results of this study could be integrated into the policy process in the formulation of local and national government plans for the future flood mitigation management and also to develop appropriate infrastructure in order to protect the lives and properties of the common people of the Medinipur district.  相似文献   
64.
Due to scarcity of local data on stormwater pollution levels and rainfall-runoff generation process, very few attempts have been made towards the management of stormwater in sub-tropical rural catchments. An attempt has been made in the present study to characterize and predict the stormwater runoff characteristics using regression modeling from five rural catchments in north-west India. Stormwater samples and flow data were collected from 75 storm events. Samples were analyzed for pH, total suspended solids (TSS), 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total kjeldhal nitrogen (TKN), total phosphorous (TP), nitrate-nitrogen (NO 3 - –N), total coliform count (TC), fecal coliform count (FC), Zn, Cu and Fe. It was found that size of the catchment and the land use practices influenced the stormwater quality even in predominantly rural areas, otherwise thought to be homogeneous. The results obtained were related with the antecedent dry days (ADD) and average rainfall. ADD was found to be positively correlated with pollutant loads whereas average rainfall showed negative correlation. The study highlights the importance of ADD in causing greater mean pollutant concentrations except for TKN, TP and NO 3 - –N. Regression models were developed for the studied catchments to estimate mean pollutant concentrations as a function of rainfall variables. Results revealed that measured pollutant concentrations demonstrated high variability with ADD and average rainfall in small rural catchments, whereas in large catchments, factors like land use, extent of imperviousness etc. resulted in low predictability of measured parameters.  相似文献   
65.
Numerical simulations are performed to understand the early thermal evolution and planetary scale differentiation of icy bodies with the radii in the range of 100–2500 km. These icy bodies include trans‐Neptunian objects, minor icy planets (e.g., Ceres, Pluto); the icy satellites of Jupiter, Saturn, Uranus, and Neptune; and probably the icy‐rocky cores of these planets. The decay energy of the radionuclides, 26Al, 60Fe, 40K, 235U, 238U, and 232Th, along with the impact‐induced heating during the accretion of icy bodies were taken into account to thermally evolve these planetary bodies. The simulations were performed for a wide range of initial ice and rock (dust) mass fractions of the icy bodies. Three distinct accretion scenarios were used. The sinking of the rock mass fraction in primitive water oceans produced by the substantial melting of ice could lead to planetary scale differentiation with the formation of a rocky core that is surrounded by a water ocean and an icy crust within the initial tens of millions of years of the solar system in case the planetary bodies accreted prior to the substantial decay of 26Al. However, over the course of billions of years, the heat produced due to 40K, 235U, 238U, and 232Th could have raised the temperature of the interiors of the icy bodies to the melting point of iron and silicates, thereby leading to the formation of an iron core. Our simulations indicate the presence of an iron core even at the center of icy bodies with radii ≥500 km for different ice mass fractions.  相似文献   
66.
Mahdi  Tew-Fik  Jain  Gaurav  Patel  Shay  Sidhu  Aman Kaur 《Natural Hazards》2019,98(1):119-135
Natural Hazards - Cyclone tracks over the Great Lakes of North America shift, both East–West as well as North–South. The reasons for the shifts are various small-scale as well as...  相似文献   
67.
Encounter of Voyager with Saturn’s environment revealed the presence of electromagnetic ion-cyclotron waves (EMIC) in Saturnian magnetosphere. Cassini provided the evidence of dynamic particle injections in inner magnetosphere of Saturn. Also inner magnetosphere of Saturn has highest rotational flow shear as compared to any other planet in our solar system. Hence during these injections, electrons and ions are transported to regions of stronger magnetic field, thus gaining energy. The dynamics of the inner magnetosphere of Saturn are governed by wave-particle interaction. In present paper we have investigated those EMIC waves pertaining in background plasma which propagates obliquely with respect to the magnetic field of Saturn. Applying kinetic approach, the expression for dispersion relation and growth rate has been derived. Magnetic field model has been used to incorporate magnetic field strength at different latitudes for radial distance of \(6.18~R_{{s}}\) (\(1~R_{{s}}= 60{,}268~\mbox{km}\)). Various parameters affecting the growth of EMIC waves in cold bi-Maxwellian background and after the hot injections has been studied. Parametric analysis inferred that after hot injections, growth rate of EMIC waves increases till \(10^{\circ}\) and decreases eventually with increase in latitude due to ion density distribution in near-equatorial region. Also, growth rate of EMIC waves increases with increasing value of temperature anisotropy and AC frequency, but the growth rate decreases as the angle of propagation with respect to \(B_{0}\) (Magnetic field at equator) increases. The injection events which assume the Loss-cone distribution of particles, affect the lower wave numbers of the spectra.  相似文献   
68.
In the problem of 2+2 bodies in the Robe’s setup, one of the primaries of mass m*1m^{*}_{1} is a rigid spherical shell filled with a homogeneous incompressible fluid of density ρ 1. The second primary is a mass point m 2 outside the shell. The third and the fourth bodies (of mass m 3 and m 4 respectively) are small solid spheres of density ρ 3 and ρ 4 respectively inside the shell, with the assumption that the mass and the radius of third and fourth body are infinitesimal. We assume m 2 is describing a circle around m*1m^{*}_{1}. The masses m 3 and m 4 mutually attract each other, do not influence the motion of m*1m^{*}_{1} and m 2 but are influenced by them. We also assume masses m 3 and m 4 are moving in the plane of motion of mass m 2. In the paper, the equations of motion, equilibrium solutions, linear stability of m 3 and m 4 are analyzed. There are four collinear equilibrium solutions for the given system. The collinear equilibrium solutions are unstable for all values of the mass parameters μ,μ 3,μ 4. There exist an infinite number of non collinear equilibrium solutions each for m 3 and m 4, lying on circles of radii λ,λ′ respectively (if the densities of m 3 and m 4 are different) and the centre at the second primary. These solutions are also unstable for all values of the parameters μ,μ 3,μ 4, φ, φ′. Such a model may be useful to study the motion of submarines due to the attraction of earth and moon.  相似文献   
69.
Transition metal-doped TiO2 nanoparticles are synthesized by sol–gel method. The as-prepared samples are characterized by various techniques to correlate structural and optical properties with chemical nature of dopants and their effect on photocatalytic degradation of diethyl phthalate esters. X-ray diffraction (XRD) reveals that all the samples are crystalline and exhibit anatase as a major phase. Chemical nature of dopants could not affect the formation of anatase and its volume fraction. The crystallite size of undoped and doped TiO2 nanoparticles varies between 10 and 12 nm as confirmed by XRD and transmission electron microscope. The lowest optical band gap observed is 2.47 eV in Mn-doped TiO2. Among all the samples, Ni-doped TiO2 sample shows better photocatalytic activity and degradation of diethyl phthalate due to its lower crystallite size and higher surface area than those of Mn- and Co-doped TiO2 samples.  相似文献   
70.
A SOTER-based automatic procedure for qualitative land evaluation is developed. This procedure was created in the automated land evaluation system (ALES). The objective was to design a procedure that allows for a quick separation of potentially suitable from non-suitable SOTER units for the intended land use, indicating constraints to different kinds of land use. Different kinds of land are unequal1y suited to various uses, land eva1uation is the assessment of the suitability of a tract of land for a specified kind of land use. In practice this implicates the comparison (matching) between the requirements of a specified land use and the properties of the land. Land evaluation concepts and definitions are treated in the paper. The ALES is a computer program that allows land evaluators to build their own knowledge-based system with which they can compute the physical and economical suitability of map units in accordance with FAO framework for land evaluation. The ALES program works with so-called decision trees, being hierarchical multiway keys in which the leaves are results (e.g., severity levels of land qualities), and the interior nodes of the tree are decision criteria (e.g., land characteristic values). These trees are traversed by the program to compute an evaluation using actual land data for each map unit. SOTAL is a SOTER-based qualitative model developed in ALES for physical land evaluation in which presently three land utilization types (LUTs) are distinguished, i.e., cultivated banana, coffee and rubber under different input and technological conditions. These LUTs are characterized by 11 landuse requirements and evaluated by matching the land use requirements with the corresponding land qualities. The paper elaborates on the criteria used in SOTAL for land quality assessment and how a final suitability rating is achieved on the basis of the rated land qualities. Results are visualized through G1S-generated maps as products in response to the specific information and data needs of decision and policy makers.  相似文献   
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