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121.
Abdul Ghaffar Muhammad Akhtar Muhammad Akbar Khan Abdul Majid Khan Khizar Samiullah Mehboob Iqbal 《Journal of the Geological Society of India》2012,80(1):119-122
Partially complete right antler from the Pinjor Formation (Pleistocene) of the Upper Siwalik Subgroup is identified, described and its phylogenetic relationship is discussed. The fossil antler is compared with other known fossil records of family Cervidae as well as with the extant species, on the basis of which it can be attributed to Axis punjabiensis. This species has not been reported previously from this fossil site. 相似文献
122.
The 4th IPCC report highlights the increased vulnerability of the coastal areas from floods due to sea-level rise (SLR).
The existing coastal flood control structures in Bangladesh are not adequate to adapt these changes and new measures are urgently
necessary. It is important to determine the impacts of SLR on flooding to analyse the performance of the existing structures
and corresponding impact to plan for suitable adaptation and mitigation measures to reduce the impacts of floods on coastal
zone. The study aims to develop a comprehensive understanding of the possible effects of SLR on floods in the coastal zone
of Bangladesh. A hydrodynamic model, which is a combination of surface and river parts, was utilized for flood simulation.
The tool was applied under a range of future scenarios, and results indicate both spatial variability of risk and changes
in flood characteristics between now and under SLR. Estimated impact on population, infrastructure and transportation is also
exposed. These types of impact estimation would be of value to flood plain management authorities to minimize the socio-economic
impact. 相似文献
123.
Cosmic energy equation is an important equation for studying the gravitational galaxy clustering in the expanding universe.
We derive the distribution function for fluctuations in particle number by using the cosmic energy equation for extended structures
(galaxies with halos). From spatial distribution function, containing particle fluctuations, we derive the velocity distribution
function to understand the influence of particle fluctuations on the velocities of galaxies.With the help of cosmic energy
equation we try to find out the physical constraints for the application of quasi-equilibrium approximation. 相似文献
124.
A self-consistent method has been evolved to infer physical parameters like density, radiation field and abundances using
line and continuum radiations as diagnostics. For that purpose, we first calculate the temperatures of graphite and silicate
grains using the model of Li and Draine (Astrophys. J. 554:778, 2001) by solving self-consistently the energy balance for G
0 (1–104) times the radiation field following Weingartner and Draine (Astrophys. J. Suppl. Ser. 134:263, 2001). Consequently, infrared emission fluxes are also obtained. To keep it simple, this is presented in the empirical form of
parameters T
D
and wavelength. The same model of the grain is adopted for photoelectric heating of gas using the formalism of Weingartner
and Draine (Astrophys. J. Suppl. Ser. 134:263, 2001) (hereafter referred to as WD) and Bakes and Tielens (Astrophys. J. 427:822, 1994) (hereafter referred to as BT) for radiation field cited above in the range (6<hν≤13.6 eV). Temperature and abundances are determined using our own code for PDR very similar to cloudy code. All the possible
sources of heating and cooling are considered for setting up the thermal balance. For the gas phase abundances that vary with
depth in the cloud due to dust, self- and mutual shielding, chemical balance is solved. Most of the photoionization, photodissociation
or chemical reaction rates are taken from UMIST database. We present an analysis of the cooling lines of singly ionized carbon
[CII] at 158 μm and neutral oxygen [OI], at 63 μm and far infrared (FIR) continuum for a variety of star forming galaxies.
Method of analysis of observational data is different from that of Malhotra et al. (Astrophys. J. 561:766, 2001). The radiation field G
0, density N
h
and abundance of carbon are obtained through best fit of observed and calculated intensities for lines and continuum radiations. 相似文献
125.
Surajit Chattopadhyay Abdul Jawad Davood Momeni Ratbay Myrzakulov 《Astrophysics and Space Science》2014,353(1):279-292
We work on the reconstruction scenario of pilgrim dark energy (PDE) in f(T,T G ). In PDE model it is assumed that a repulsive force that is accelerating the Universe is phantom type with (w DE 1) and it is so strong that prevents formation of the black hole. We construct the f(T,T G ) models and correspondingly evaluate equation of state parameter for various choices of scale factor. Also, we assume polynomial form of f(T,T G ) in terms of cosmic time and reconstruct H and w DE in this manner. Through discussion, it is concluded that PDE shows aggressive phantom-like behavior for s=?2 in f(T,T G ) gravity. 相似文献
126.
Lawal Billa Hamid Assilzadeh Shattri Mansor Ahmed R. Mahmud Abdul H. Ghazali 《Central European Journal of Geosciences》2011,3(3):309-317
Observed rainfall is used for runoff modeling in flood forecasting where possible, however in cases where the response time of the watershed is too short for flood warning activities, a deterministic quantitative precipitation forecast (QPF) can be used. This is based on a limited-area meteorological model and can provide a forecasting horizon in the order of six hours or less. This study applies the results of a previously developed QPF based on a 1D cloud model using hourly NOAA-AVHRR (Advanced Very High Resolution Radiometer) and GMS (Geostationary Meteorological Satellite) datasets. Rainfall intensity values in the range of 3–12 mm/hr were extracted from these datasets based on the relation between cloud top temperature (CTT), cloud reflectance (CTR) and cloud height (CTH) using defined thresholds. The QPF, prepared for the rainstorm event of 27 September to 8 October 2000 was tested for rainfall runoff on the Langat River Basin, Malaysia, using a suitable NAM rainfall-runoff model. The response of the basin both to the rainfall-runoff simulation using the QPF estimate and the recorded observed rainfall is compared here, based on their corresponding discharge hydrographs. The comparison of the QPF and recorded rainfall showed R2 = 0.9028 for the entire basin. The runoff hydrograph for the recorded rainfall in the Kajang sub-catchment showed R2 = 0.9263 between the observed and the simulated, while that of the QPF rainfall was R2 = 0.819. This similarity in runoff suggests there is a high level of accuracy shown in the improved QPF, and that significant improvement of flood forecasting can be achieved through ‘Nowcasting’, thus increasing the response time for flood early warnings. 相似文献
127.
Mohamad Rosni OthmanAuthor Vitae George James BruceAuthor Vitae Saharuddin Abdul HamidAuthor Vitae 《Ocean & Coastal Management》2011,54(8):557-568
A comprehensive maritime industry policy that can be adequately monitored to achieve a competitive advantage is important. The Malaysian maritime industry comprises multifaceted sectors that are governed by fragmented governmental agencies. In this research, we investigated the Malaysian maritime industry cluster comprising three main sectors: Shipping, Ship Industry, Ports and Terminals. The Strength Indicator Model has been developed to reveals the maritime industry cluster. We find that the Competitions, Locations, Connections, Government and Chances factors affect the capability of the Malaysian maritime industry cluster. The result of this study will give a framework for Regulatory bodies and the various stakeholders to support the Malaysia maritime industry progressing toward a more competitive and sustainable development of the industry with the aim to become the developed maritime nation. 相似文献
128.
High-resolution Surface Relative Humidity Computation Using MODIS Image in Peninsular Malaysia 总被引:4,自引:0,他引:4
1 Introduction The Canadian Fire Weather Index (FWI) System can be used in applied forestry as a tool to investigate and manage all types of fire management (Chrosciewicz, 1978; McRae, 1980; Fyles et al., 1991; McRae et al., 1994). The development of the FWI system (Van Wag- ner, 1987; 1990) over the last two decades allows the routine prediction of fire behavior from weather data (Fyles et al., 1991). The FWI is calculated from point measurements of air temperature, relative humidity… 相似文献
129.
130.
Ruzinoor Che Mat Abdul Rashid Mohamed Shariff Biswajeet Pradhan Ahmad Rodzi Mahmud Mohd Shafry Mohd Rahim 《Arabian Journal of Geosciences》2013,6(12):4881-4889
The objective of this paper is to discuss the effectiveness of visualizing online 3D terrain draped with different satellite imageries. The topographic data of the study area were obtained from the contour maps of Universiti Putra Malaysia, Selangor, Malaysia. The high resolution satellite imageries used in this project involving QUICKBIRD (0.6 m resolution), IKONOS (1 m resolution), and SPOT5 (5 m resolution). R2V software was used for editing the contour data, whereas Arc GIS was used for overlaying the imageries over the 3D terrain data. Then the data were exported into Virtual Reality Markup Language to compare the effectiveness of different satellite imageries based on the data file size, imageries size, number of images tile, loading time during office hours (from 8 a.m. to 5 p.m.) and out of office hours (after 5 p.m.), frame rate per second, and visualization quality. The results revealed that IKONOS satellite imageries are better for an effective online 3D terrain visualization utilizing GIS data even though it has lower resolution compared to QUICKBIRD. 相似文献