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11.
Omar Alkouri Husaini Omar Mohammed Abu Shariah Ahmad Rodzi Shattri Mansor Zainuddin Md. Yusof 《Journal of the Geological Society of India》2012,79(5):515-524
Limestone bedrock topography has complex phenomena and highly relief subsurface topography due to the presence of karstic
features. Geotechnical and environmental problems arise whenever foundations are established on the surface of the limestone
bedrock or within the overburden soils. Geographical information system (GIS) and remote sensing are emerging as powerful
techniques widely applicable in natural resources management to detect land use changes and devise strategies based on these
changes. The study focuses on using aerial photography for the detection of changes and effects of mining on geomorphology,
especially the use of sequential images that allows to detect changes taken place from time to time, by using. Volumetric
Surface Movement Spatiotemporal Data Model (VSMSDM) application has been employed to create karst terrain surface movements
and visualized 3D information in the Virtual Geographical Information Systems (VGIS). VSMSDM application was implemented by
developing prototype of visualization system using with integrated time in the TIN structure. The data have been collected
from aerial photography in 1981 and 2004, and the results displayed that the proposed data model is able to view the changing
in karst topography to detect significant landscapes and landforms changes. 相似文献
12.
The astrophysical S-factor of the experimental cross section data of the main reactions in the proton–proton chain, i.e. 3He(3He,2p)4He, 3He(4He,γ)7Be and 7Be(p,γ)8B, are reanalyzed by using the exact tunneling probability in nuclear reactions. Our goal is to test this treatment in finding the reaction rate per pair for non-resonant reactions. At low temperatures, the exact treatment is identical to the standard formalism but diverges at higher temperatures. 相似文献
13.
Norzaida Abas Zalina M. Daud Fadhilah Yusof 《Theoretical and Applied Climatology》2014,118(3):597-607
A stochastic rainfall model is presented for the generation of hourly rainfall data in an urban area in Malaysia. In view of the high temporal and spatial variability of rainfall within the tropical rain belt, the Spatial–Temporal Neyman–Scott Rectangular Pulse model was used. The model, which is governed by the Neyman–Scott process, employs a reasonable number of parameters to represent the physical attributes of rainfall. A common approach is to attach each attribute to a mathematical distribution. With respect to rain cell intensity, this study proposes the use of a mixed exponential distribution. The performance of the proposed model was compared to a model that employs the Weibull distribution. Hourly and daily rainfall data from four stations in the Damansara River basin in Malaysia were used as input to the models, and simulations of hourly series were performed for an independent site within the basin. The performance of the models was assessed based on how closely the statistical characteristics of the simulated series resembled the statistics of the observed series. The findings obtained based on graphical representation revealed that the statistical characteristics of the simulated series for both models compared reasonably well with the observed series. However, a further assessment using the AIC, BIC and RMSE showed that the proposed model yields better results. The results of this study indicate that for tropical climates, the proposed model, using a mixed exponential distribution, is the best choice for generation of synthetic data for ungauged sites or for sites with insufficient data within the limit of the fitted region. 相似文献
14.
R. Abiri M. Maziah N. A. Shaharuddin Z. N. B. Yusof N. Atabaki M. M. Hanafi M. Sahebi P. Azizi N. Kalhori A. Valdiani 《International Journal of Environmental Science and Technology》2017,14(5):1091-1108
Enhancing of the efficient tissue culture protocol for somatic embryos would facilitate the engineered breeding plants program. In this report, we describe the reproducible protocol of Malaysian rice (Oryza sativa L.) cultivar MR219 through somatic embryogenesis. Effect of a wide spectrum of exogenesis materials was assessed in three phases, namely callogenesis, proliferation and regeneration. Initially, rice seeds were subjected under various auxin treatments. Secondly, the effect of different concentrations of 2,4-D on callus induction was evaluated. In the next step, the efficiency of different explants was identified. Subsequently, the effects of different auxins, cytokinins, l-proline, casein hydrolysate and potassium metasilicate concentrations on the callus proliferation and regeneration were considered. For the callogenesis phase, 2 mg L?1of 2,4-D and roots were chosen as the best auxin and explant. In the callus proliferation stage, the highest efficiency was observed at week eight in the MS media supplemented with 2 mg L?1 of 2,4-D, 2 mg L?1 of kinetin, 50 mg L?1 of l-proline, 100 mg L?1 of casein hydrolysate and 30 mg L?1 of potassium metasilicate. In the last phase of the research, the MS media added with 3 mg L?1 of kinetin, 30 mg L?1of potassium metasilicate and 2 mg L?1 of NAA were selected. Meanwhile, to promote the roots of regenerated explants, 0.4 mg L?1 of IBA has shown potential as an appropriate activator. 相似文献
15.
Tan Wei Lun Yusof Fadhilah Yusop Zulkifli 《Theoretical and Applied Climatology》2017,129(1-2):577-586
This study involves the modelling of a homogeneous hidden Markov model (HMM) on the northeast rainfall monsoon using 40 rainfall stations in Peninsular Malaysia for the period of 1975 to 2008. A six hidden states HMM was selected based on Bayesian information criterion (BIC), and every hidden state has distinct rainfall characteristics. Three of the states were found to correspond by wet conditions; while the remaining three states were found to correspond to dry conditions. The six hidden states were found to correspond with the associated atmospheric composites. The relationships between El Niño–Southern Oscillation (ENSO) and the sea surface temperatures (SST) in the Pacific Ocean are found regarding interannual variability. The wet (dry) states were found to be well correlated with a Niño 3.4 index which was used to characterize the intensity of an ENSO event. This model is able to assess the behaviour of the rainfall characteristics with the large scale atmospheric circulation; the monsoon rainfall is well correlated with the El Niño–Southern Oscillation in Peninsular Malaysia.
相似文献16.
Glyphosate is globally a widely used herbicide, yet there is little information on their toxicity to marine fishes. Java medaka, a small tropical fish native to coastal areas in several Southeast Asian countries, is viewed as a suitable candidate for toxicity test and thus was used for this study. Java medaka adults were cultured in the laboratory and the fertilized eggs of the F2 generation were exposed to different concentrations of glyphosate-based herbicide (100, 200, 300, 400 and 500 ppm) until they hatched. The survival and hatching rates of the embryos, changes in the heart rate and morphological impairments were recorded. Generally, survival and hatching percentage decreased as glyphosate concentration increased. Absence of pectoral fin(s) and cornea, permanently bent tail, irregular shaped abdomen, and cell disruption in the fin, head and abdomen are among the common teratogenic effects observed. Furthermore, risk factor also increased with the increased in glyphosate concentrations. 相似文献
17.
Akmal Khodzori Fikri Shahbudin Saad Faiz Mohd Hanapiah Muhammad Hamizan Yusof Muhammad 《Ocean Science Journal》2019,54(3):435-456
Ocean Science Journal - The species lists of scleractinian hard corals in Peninsular Malaysia have not been updated for 15 years. The present study aimed to determine the diversity and abundance... 相似文献
18.
Several organisms have been used as indicators, bio-monitoring agents or test organisms in ecotoxicological studies. A close relative of the well established Japanese medaka, the Java medaka (Oryzias javanicus), has the potential to be a test organism. The fish is native to the estuaries of the Malaysian Peninsula, Thailand, Indonesia and Singapore. In this study, newly fertilised eggs were exposed to different concentrations of Cd and Hg. Observations were done on the development of the embryos. Exposure to low levels of Cd and Hg (0.01-0.05 ppm) resulted in several developmental disorders that led to death. Exposure to ≥1.0 ppm Cd resulted in immediate developmental arrest. The embryos of Java medaka showed tolerance to a certain extent when exposed to ≥1.0 ppm Hg compared to Cd. Based on the sensitivity of the embryos, Java medaka is a suitable test organism for ecotoxicology in the tropical region. 相似文献
19.
Mansir Aminu Abdul Nasir Matori Khamaruzaman Wan Yusof Amirhossein Malakahmad Rosilawati Binti Zainol 《Arabian Journal of Geosciences》2017,10(13):286
Sustainable approach to tourism development is rarely addressed among authorities and participants. This research presents an approach based on an integrated use of analytic network process (ANP) and geographic information system (GIS) for sustainable tourism planning in Cameron Highlands, Malaysia. ANP was utilized to evaluate the relative priorities for the sustainable tourism development of the highlands based on chosen criteria. ANP results were then transferred into GIS environment and attached to their respective criterion maps. Subsequently, GIS-based sustainable tourism map was generated, which defines the various types of tourism activities that are compatible with the highlands according to the sensitivity of the highland’s environment. The final output was validated using Cameron Highlands Local Plan. 相似文献
20.
Rainfall characterisation by application of standardised precipitation index (SPI) in Peninsular Malaysia 总被引：1，自引：1，他引：0
Fadhilah Yusof Foo Hui-Mean Jamaludin Suhaila Zulkifli Yusop Kong Ching-Yee 《Theoretical and Applied Climatology》2014,115(3-4):503-516
The interpretations of trend behaviour for dry and wet events are analysed in order to verify the dryness and wetness episodes. The fitting distribution of rainfall is computed to classify the dry and wet events by applying the standardised precipitation index (SPI). The rainfall amount for each station is categorised into seven categories, namely extremely wet, severely wet, moderately wet, near normal, moderately dry, severely dry and extremely dry. The computation of the SPI is based on the monsoon periods, which include the northeast monsoon, southwest monsoon and inter-monsoon. The trends of the dry and wet periods were then detected using the Mann–Kendall trend test and the results indicate that the major parts of Peninsular Malaysia are characterised by increasing droughts rather than wet events. The annual trends of drought and wet events of the randomly selected stations from each region also yield similar results. Hence, the northwest and southwest regions are predicted to have a higher probability of drought occurrence during a dry event and not much rain during the wet event. The east and west regions, on the other hand, are going through a significant upward trend that implies lower rainfall during the drought episodes and heavy rainfall during the wet events. 相似文献