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601.
A. N. Khondaker Karim Malik Nahid Hossain Shaikh Abdur Razzak Rouf Ahmad Khan 《Climate Policy》2013,13(4):517-541
The energy sector is the main contributor to GHG emissions in Saudi Arabia. The tremendous growth of GHG emissions poses serious challenges for the Kingdom in terms of their reduction targets, and also the mitigation of the associated climate changes. The rising trend of population and urbanization affects the energy demand, which results in a faster rate of increase in GHG emissions. The major energy sector sources that contribute to GHG emissions include the electricity generation, road transport, desalination plants, petroleum refining, petrochemical, cement, iron and steel, and fertilizer industries. In recent years, the energy sector has become the major source, accounting for more than 90% of national CO2 emissions. Although a substantial amount of research has been conducted on renewable energy resources, a sustainable shift from petroleum resources is yet to be achieved. Public awareness, access to energy-efficient technology, and the development and implementation of a legislative framework, energy pricing policies, and renewable and alternative energy policies are not mature enough to ensure a significant reduction in GHG emissions from the energy sector. An innovative and integrated solution that best serves the Kingdom's long-term needs and exploits potential indigenous, renewable, and alternative energy resources while maintaining its sustainable development stride is essential.Policy relevanceThe main contributor to GHG emissions in Saudi Arabia is the energy sector that accounts for more than 90% of the national CO2 emissions. Tremendous growth of GHG emissions poses serious challenges for the Kingdom in their reduction and mitigating the associated climate changes. This study examines the changing patterns of different activities associated with energy sector, the pertinent challenges, and the opportunities that promise reduction of GHG emissions while providing national energy and economic security. The importance of achieving timely, sustained, and increasing reductions in GHG emissions means that a combination of policies may be needed. This study points to the long-term importance of making near- and medium-term policy choices on a well-informed, strategic basis. This analytical paper is expected to provide useful information to the national policy makers and other decision makers. It may also contribute to the GHG emission inventories and the climate change negotiations. 相似文献
602.
603.
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
604.
hydrologic models are important tools to estimate runoff from a catchment. Identification of broad based parameters of a hydrologic
model for development of direct runoff hydrograph is a key issue for the modelers. Optimization and regionalization of hydrologic
parameters for application of Nash’s model is investigated in this paper. Six catchments dominated by hill torrent flows were
selected for this purpose. Fifty seven rainfall events were used for regionalization of parameters and about 55 events were
used for validation of the results. The hydrologic parameters of the Nash Model, number of linear cascades (N) and storage
coefficient (k) were determined using optimization based upon Downhill Simplex method. The data was collected by field measurements
and from Water and Power Development Authority (WAPDA) Pakistan. The physical parameters of the catchments were derived from
the satellite images of the watersheds with the help of ERDAS software. The performance of the model was assessed by the model
efficiency. It is concluded that the conceptual Nash model can simulate direct runoff hydrograph using regional hydrologic
parameters with model efficiency of 67%. 相似文献
605.
Khairayu Badron Ahmad Fadzil Ismail Jafri Din Abd.Rahman Tharek 《Journal of Atmospheric and Solar》2011,73(5-6):601-610
Satellite communications operating at 10 GHz and above in the tropics suffer severe signal degradation due to rain. Attenuation due to rain at 38 GHz had been measured for a period of 20 months in Malaysia. Analyses carried out include seasonal variations, diurnal effects and the annual cumulative distributions. Obtained results were compared with several established prediction models including the ITU-R. The rain fade characteristics were also investigated in determining the levels of signal loss and fading. In addition, the studies highlight several potential fade mitigation techniques that can be embarked. These fundamental aprehensions are very critical for future earth space communication link design and can be exploited as preliminary groundwork plan for the researchers as well as engineers. 相似文献
606.
607.
Ade Faisal Taksiah A. Majid Fauziah Ahmad Felix Tongkul Syafrina Mayang Sari 《Natural Hazards》2011,59(1):237-269
The seismic hazard assessment of a site that lies in the low seismic region affected by the future existence of a large dam
has been given less attention in many studies. Moreover, this condition is not addressed directly in the current seismic codes.
This paper explains the importance of such information in mitigating the seismic hazard properly. Ulu Padas Area in Northern
Borneo is used as an example for a case study of a site classified as a low seismic region. It is located close to the border
of Malaysia, Brunei Darussalam, and Indonesia and may have a large dam in the future as the region lies in hilly geography
with river flow. This study conducts probabilistic and deterministic seismic hazard analyses, and reservoir-triggered seismicity
of a site affected by the future existence of a large dam. The result shows that the spectrum acceleration of the maximum
design earthquake for the investigated site in the Ulu Padas Area in Northern Borneo is taken from the reservoir-triggered
seismicity earthquake at short periods and from the current condition at longer periods. 相似文献
608.
This research makes use of the remote sensing, simulation modeling and field observations to assess the non-point source pollution
load of a Himalayan lake from its catchment. The lake catchment, spread over an area of about 11 km2, is covered by different land cover types including wasteland (36%), rocky outcrops (30%), agriculture (12%), plantation
(12.2%), horticulture (6.2%) and built-up (3.1%) The GIS-based distributed modeling approach employed relied on the use of
geospatial data sets for simulating runoff, sediment, and nutrient (N and P) loadings from a watershed, given variable-size
source areas, on a continuous basis using daily time steps for weather data and water balance calculations. The model simulations
showed that the highest amount of nutrient loadings are observed during wet season in the month of March (905.65 kg of dissolved
N, 10 kg of dissolved P, 10,386.81 kg of total N and 2,381.89 kg of total P). During the wet season, the runoff being the
highest, almost all the excess soil nutrients that are trapped in the soil are easily flushed out and thus contribute to higher
nutrient loading into the lake during this time period. The 11-year simulations (1994–2004) showed that the main source areas
of nutrient pollution are agriculture lands and wastelands. On an average basis, the source areas generated about 3,969.66 kg/year
of total nitrogen and 817.25 kg/year of total phosphorous. Nash–Sutcliffe coefficients of correlation between the daily observed
and predicted nutrient load ranged in value from 0.80 to 0.91 for both nitrogen and phosphorus. 相似文献
609.
Saeid Sadeghian Mohammad Javad Valadan Zoej Mahmoud Reza Delavar Ahmad Abootalebi 《International Journal of Applied Earth Observation and Geoinformation》2001,3(4):366
The huge capability of high resolution satellite imageries (HRSI), that includes spatial, spectral, temporal and radiometric resolutions as well as stereoscopic vision introduces them as a powerful new source for the Photogrammetry, Remote Sensing and GIS communities. High resolution data increases the need for higher accuracy of data modeling. The satellite orbit, position, attitude angles and interior orientation parameters have to be adjusted in the geometrical model to achieve optimal accuracy with the use of a minimum number of Ground Control Points (GCPs). But most high resolution satellite vendors do not intend to publish their sensor models and ephemeris data. There is consequently a need for a range of alternative, practical approaches for extracting accurate 2D and 3D terrain information from HRSI. The flexibility and good accuracy of the alternative models demonstrated with KFA-1000 and the well-known SPOT level 1A images. A block of eight KFA-1000 space photos in two strips with 60% longitudinal overlap and 15% lateral sidelap and SPOT image with rational function, DLT, 2D projective, polynomials, affine, conformal, multiquadric and finite element methods were used in the test. The test areas cover parts of South and West of Iran. Considering the quality of GCPs, the best result was found with the DLT method with a RMSE of 8.44 m for the KFA-1000 space photos. 相似文献
610.
Channel migration includes any change of river channel geometry within the context of the cross-section, pattern or network in a drainage basin. To study the dynamic behaviour of a river, measurements taken with conventional ground-based instruments are time-consuming and expensive. Remote sensing techniques are capable of providing a measure of surface variability including dynamic behaviour of channels, reasonably quickly due to availability of the repetitive remotely-sensed data. These data are well suited for the assessment and monitoring of dynamic changes on the surface of the earth. In the present study Landsat MSS and TM data of winter season in the form of false colour composites (FCC) of years 1982 and 1987 were used for the delineation of river Ganga course lying between Allahabad and Buxar. The interpretation of satellite data was carried out using visual interpretation technique for the assessment of channel migration. The shift in river banks delineated from satellite data were measured with respect to river banks identified from topographical base map. The maximum shift observed in mid channel is 4. 55 km while maximum left and right banks shifts are 4.6 and 4.8 km, respectively. 相似文献