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81.
L. C. Abdullah Ph.D. L. L. Wong M.Sc. M. Saari Ph.D. A. Salmiaton Ph.D. M. S. Abdul Rashid Ph.D. 《International Journal of Environmental Science and Technology》2007,4(2):271-278
The emissions from palm oil industry through incineration and open burning are the major sources of air pollutions contribution in Malaysia. The consequence of increasing the particulate concentration, the particulate matter dissolves with vapour and grows into droplets when the humidity exceeds approximately 70% and causing opaque situation known as haze. This work focuses on the dispersion particulate matter from palm oil mill. Gaussian Plume Model from a point source, subject to various atmospheric conditions is used to calculate particulate matter concentration then display the distribution of plume dispersion using geographic information system. Atmospheric Stability, mixing height, wind direction, wind speed, natural and artificial features play an important role in dispersion process. Study on the dispersion of particulate matters and the haze potential are presented as a case study in this paper. The data obtained will be served as the purpose of modeling the transport of particulate matter for obtaining permits and prevention of significant deterioration to the environment. 相似文献
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Seena G. Muraleedharan K. R. Revichandran C. Azeez S. Abdul John Sebin Nair Ravikumar C. 《Ocean Dynamics》2022,72(3):207-222
Ocean Dynamics - The time-dependent plume front positioning with respect to different tidal phases and its dynamics coupled with seasonal river efflux on the shelf off Kochi, southwest coast of... 相似文献
84.
The energy balance equation for a general solar atmosphere without assuming the plane-parallel approximation is solved analytically. This leads to models for both the transition region and inner corona as well as for the outer corona. The form of the latter is very similar to that of the hydrostatic conduction model of Chapman (1957). However, in this paper we confine ourselves only to the former.Model I is electron-pressure dependent but model II depends particularly on the maximum coronal temperature T
m and its corresponding altitude h
m. Both the models are compared with recently constructed temperature models of Chiuderi and Riani (1974), McWhirter et al. (1975), and Gabriel (1976a). It is concluded that our model II reproduces these models within a factor of not more than 2. 相似文献
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Natural soils are one of the most inherently variables in the ground. Although the significance of inherent soil variability in relation to reliable predictions of consolidation rates of soil deposits has long been realized, there have been few studies that addressed the issue of soil variability for the problem of ground improvement by prefabricated vertical drains. Despite showing valuable insights into the impact of soil spatial variability on soil consolidation by prefabricated vertical drains, available stochastic works on this subject are based on a single‐drain (or unit cell) analyses. However, how the idealized unit cell solution can be a supplement to the complex multi‐drain systems for spatially variable soils has never been addressed in the literature. In this study, a rigorous stochastic finite elements modeling approach that allows the true nature of soil spatial variability to be considered in a reliable and quantifiable manner, both for the single‐drain and multi‐drain systems, is presented. The feasibility of performing an analysis based on the unit cell concept as compared with the multi‐drain analysis is assessed in a probabilistic context. It is shown that with proper input statistics representative of a particular domain of interest, both the single‐drain and multi‐drain analyses yield almost identical results. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Abhik Kundu Abdul Matin Malay Mukul Patrick G. Eriksson 《Journal of the Geological Society of India》2011,78(4):321-336
The Himalayan fold-and-thrust belt has propagated from its Tibetan hinterland to the southern foreland since ∼55 Ma. The Siwalik
sediments (∼20 - 2 Ma) were deposited in the frontal Himalayan foreland basin and subsequently became part of the thrust belt
since ∼ 12 Ma. Restoration of the deformed section of the Middle Siwalik sequence reveals that the sequence is ∼325 m thick.
Sedimentary facies analysis of the Middle Siwalik rocks points to the deposition of the Middle Siwalik sediments in an alluvial
fan setup that was affected by uplift and foreland-ward propagation of Greater and Lesser Himalayan thrusts. Soft-sediment
deformation structures preserved in the Middle Siwalik sequence in the Darjiling Himalaya are interpreted to have formed by
sediment liquefaction resulting from increased pore-water pressure probably due to strong seismic shaking. Soft-sediment structures
such as convolute lamination, flame structures, and various kinds of deformed cross-stratification are thus recognized as
palaeoseismic in origin. This is the first report of seismites from the Siwalik succession of Darjiling Himalaya which indicates
just like other sectors of Siwalik foreland basin and the present-day Gangetic foreland basin that the Siwalik sediments of
this sector responded to seismicity. 相似文献
90.
3D building models of the world exhibit multi-scale properties. Different level-of-details (LoDs) are important for different applications. Therefore, generation of multi-scale representation of 3D building models to fulfill the demands of these applications is a generalization problem. In order to generalize 3D buildings, different pieces of information need to be preserved or removed to restrict the amount of data represented on a certain LoD. In this work, a three-step strategy based on simplification, aggregation and reconstruction of generalized buildings represented in City Geography Markup Language (CityGML) is proposed. The minimum length of edges (threshold value) for removal of amount of data is restricted to generalization specifications of CityGML characterized by differing accuracies and minimal dimensions of objects for each LoD. The main part of this paper is simplification of ground plans. For this purpose, a new approach is proposed to restrict number of edges, curves, and corners of ground plan of 3D building model on a certain LoD. Algorithms for simplification with the aim to derive LoD1 from exterior shells of buildings at LoD3 are implemented and tested on a number of buildings of Putrajaya city. The experiments showed that length of edge as threshold value is directly proportional to the size of generalized models. 相似文献