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41.
42.
The Miocene to Modern Baram Delta Province is a highly efficient source to sink system that has accumulated 9 to 12 km of coastal–deltaic to shelf sediments over the past 15 Myr. Facies analysis based on ca 1 km of total vertical outcrop stratigraphy, combined with subsurface geology and sedimentary processes in the present‐day Baram Delta Province, suggests a ‘storm‐flood’ depositional model comprising two distinct periods: (i) fair‐weather periods are dominated by alongshore sediment reworking and coastal sand accumulation; and (ii) monsoon‐driven storm periods are characterized by increased wave‐energy and offshore‐directed downwelling storm flow that occur simultaneously with peak fluvial discharge caused by storm precipitation (‘storm‐floods’). The modern equivalent environment has the following characteristics: (i) humid‐tropical monsoonal climate; (ii) narrow (ca <100 km) and steep (ca 1°), densely vegetated, coastal plain; (iii) deep tropical weathering of a mudstone‐dominated hinterland; (iv) multiple independent, small to moderate‐sized (102 to 105 km2) drainage basins; (v) predominance of river‐mouth bypassing; and (vi) supply‐dominated shelf. The ancient, proximal part of this system (the onshore Belait Formation) is dominated by strongly cyclical sandier‐upward successions (metre to decametre‐scale) comprising (from bottom to top): (i) finely laminated mudstone with millimetre‐scale silty laminae; (ii) heterolithic sandstone–mudstone alternations (centimetre to metre‐scale); and (iii) sharp‐based, swaley cross‐stratified sandstone beds and bedsets (metre to decimetre‐scale). Gutter casts (decimetre to metre‐scale) are widespread, they are filled with swaley cross‐stratified sandstone and their long axes are oriented perpendicular to the palaeo‐shoreline. The gutter casts and other associated waning‐flow event beds suggest that erosion and deposition was controlled by high‐energy, offshore‐directed, oscillatory‐dominated, sediment‐laden combined flows within a shoreface to delta front setting. The presence of multiple river mouths and exceptionally high rates of accommodation creation (characteristic of the Neogene to Recent Baram Delta Province; up to 3000 m Ma−1), in a ‘storm‐flood’‐dominated environment, resulted in a highly efficient and effective offshore‐directed sediment transport system.  相似文献   
43.
Indoor navigation is important for various applications such as disaster management, building modeling, safety analysis etc. In the last decade, indoor environment has been a focus of wide research that includes development of indoor data acquisition techniques, 3D data modeling and indoor navigation. In this research, an automated method for 3D modeling of indoor navigation network has been presented. 3D indoor navigation modeling requires a valid 3D model that can be represented as a cell complex: a model without any gap or intersection such that two cells (e.g. room, corridor) perfectly touch each other. This research investigates an automated method for 3D modeling of indoor navigation network using a geometrical model of indoor building environment. In order to reduce time and cost of surveying process, Trimble LaserAce 1000 laser rangefinder was used to acquire indoor building data which led to the acquisition of an inaccurate geometry of building. The connection between surveying benchmarks was established using Delaunay triangulation. Dijkstra algorithm was used to find shortest path in between building floors. The modeling results were evaluated against an accurate geometry of indoor building environment which was acquired using highly-accurate Trimble M3 total station. This research intends to investigate and propose a novel method of topological navigation network modeling with a less accurate geometrical model to overcome the need of required an accurate geometrical model. To control the uncertainty of the calibration and of the reconstruction of the building from the measurements, interval analysis and homotopy continuation will be investigated in the near future.  相似文献   
44.
The current paper examines the relationship between health financing (public and out-of-pocket health financing), CO2 emission and health outcomes in 35 Sub-Saharan African countries for the period of 1995–2012. The panel unit root and cointegration tests are conducted as pre-tests, followed by the estimation of the parameters using the FM-OLS and DOLS techniques. The findings of the study show the importance of public health financing as one of the major factors that lead to better health outcomes, whereas the out-of-pocket expenditure is found to be harmful to population health since it leads to increase under-5 mortality rate. Although the results show a negative relationship between CO2 and health outcomes, still these results remain inclusive. In addition, the findings reveal the importance of socioeconomic factors such as income and education as key determinants of health outcomes.  相似文献   
45.
The paper deals with the study of the physical and dynamical characteristics of a severe thunderstorm, which had occurred on April 5, 2015, at about 2100 UTC in the southwestern Bangladesh with location around 23.3–23.7N and 89.0–89.4E within the upazilas (sub-districts) of Kumarkhali and Shailkupa under the districts of Kushtia and Jhenaidah, respectively. The thunderstorm was associated with numerous hails of large size. More than 5000 birds which used to live in the bird sanctuary at Shailkupa and 22,011 birds in Chhaglapara Bird Sanctuary of Kumarkhali died as they were hit by the hails. Large hails also damaged crops, houses and forests over the thunderstorm hit areas. The evolution of the thunderstorm is studied by the WRF model, which is initialized using the National Centers for Environmental Prediction Final reanalysis data of 0000 UTC of April 5, 2015. The simulated results provide a basis to study the physical and dynamical characteristics of the thunderstorm, which are generally not identified by the meteorological observations which are too sparse. The model has captured a micro-low over Kumarkhali and its neighborhood, which favored the occurrence of the severe thunderstorm. The model simulated rainfall is about 26 mm near the place of occurrence, which matches well with the area where the reflectivity of hydrometeor is maximum. The convective available potential energy is found to be 1600 J kg?1 at 1730 UTC near the place of occurrence of the thunderstorm; this indicates high atmospheric instability over the thunderstorm location for the formation of the thunderstorm. The vertical velocity, convergence, cloud water mixing ratio and the ice water mixing ratio and their vertical extensions are found to be satisfactory and responsible for the occurrence of large hails associated with the thunderstorm.  相似文献   
46.
A study was done to determine the concentrations of surfactants on the sea-surface microlayer and in atmospheric aerosols in several coastal areas around the Malaysian peninsula. The concentrations of surfactants from the sea-surface microlayer (collected using rotation drum) and from aerosols (collected using HVS) were analyzed as methylene blue active substances and disulphine blue active substances through the colorimetric method using a UV-vis spectrophotometer. The results of this study showed that the average concentrations of surfactants in the sea-surface microlayer ranged between undetected and 0.36 ± 0.34 μmol L−1 for MBAS and between 0.11 ± 0.02 and 0.21 ± 0.13 μmol L−1 for DBAS. The contribution of surfactants from the sea-surface microlayer to the composition of surfactants in atmospheric aerosols appears to be very minimal and more dominant in fine mode aerosols.  相似文献   
47.
The accuracy of Artificial Neural Network (ANN), Adaptive Neuro-Fuzzy Inference System (ANFIS), wavelet-ANN and wavelet-ANFIS in predicting monthly water salinity levels of northwest Iran’s Aji-Chay River was assessed. The models were calibrated, validated and tested using different subsets of monthly records (October 1983 to September 2011) of individual solute (Ca2+, Mg2+, Na+, SO4 2? and Cl?) concentrations (input parameters, meq L?1), and electrical conductivity-based salinity levels (output parameter, µS cm?1), collected by the East Azarbaijan regional water authority. Based on the statistical criteria of coefficient of determination (R2), normalized root mean square error (NRMSE), Nash–Sutcliffe efficiency coefficient (NSC) and threshold statistics (TS) the ANFIS model was found to outperform the ANN model. To develop coupled wavelet-AI models, the original observed data series was decomposed into sub-time series using Daubechies, Symlet or Haar mother wavelets of different lengths (order), each implemented at three levels. To predict salinity input parameter series were used as input variables in different wavelet order/level-AI model combinations. Hybrid wavelet-ANFIS (R2 = 0.9967, NRMSE = 2.9 × 10?5 and NSC = 0.9951) and wavelet-ANN (R2 = 0.996, NRMSE = 3.77 × 10?5 and NSC = 0.9946) models implementing the db4 mother wavelet decomposition outperformed the ANFIS (R2 = 0.9954, NRMSE = 3.77 × 10?5 and NSC = 0.9914) and ANN (R2 = 0.9936, NRMSE = 3.99 × 10?5 and NSC = 0.9903) models.  相似文献   
48.
The Central Indian Tectonic Zone (CITZ) is a major tectonic feature extending across the Indian subcontinent. It was formed in the Paleoproterozoic when the Bastar Craton and the Bundelkhand Craton were sutured together. This region is recognized in the geological record as a persistent zone of weakness with many tectonothermal events occurring over geologic time. The weakness of this region may have caused the late Cretaceous/early Tertiary Deccan volcanism to have been localized in the CITZ. The zone is still tectonically active, as evidenced by sustained levels of seismic activity. This paper presents the first systematic investigation of the resistivity structure of the CITZ using multiple magnetotelluric (MT) transects. Two-dimensional (2D) resistivity models were generated for five north–south profiles that cross the CITZ and encompass an area of ~60,000 km2. The models were based on the joint inversion of transverse electric (TE), transverse magnetic (TM) and tipper (Hz) data. All the profiles showed a low resistive (10–80 Ωm) middle to lower crust beneath the CITZ with a crustal conductance of 300–800 S. The presence of an interconnected fluid phase and/or hydrous/metallic minerals appears to be the most likely explanation for the elevated conductivity that is observed beneath the CITZ. The presence of fluids is significant because it may indicate the cause of persistent weakness at crustal depths. A northward dip of both the crustal conductive layer and coincident seismic reflections favor a northward polarity of the subduction process associated with the formation of the CITZ.  相似文献   
49.
The Chaman left‐lateral strike‐slip fault bounds the rigid Indian plate boundary at the western end of the Himalayan‐Tibetan orogen and is marked by contrasting topographic relief. Deformed landforms along the fault provide an excellent record for understanding this actively evolving intra‐continental strike‐slip fault. The geomorphic response of an active transpessional stretch of the Chaman fault was studied using digital elevation model (DEM) data integrated with Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Visible and Near Infrared/Short Wave Infrared (VNIR/SWIR) and images from GeoEye‐1. Geologic and geomorphic mapping helped in reconstructing the Late Quaternary landscape history of this transpessional strand of the Chaman strike‐slip fault and the associated Spinatizha thrust fault in western Pakistan. Topographic analysis of a part of the transpression (the thrust bounded Roghani ridge) revealed northward growth of the Spinatizha fault with the presence of three water gaps and two corresponding wind gaps. Geomorphic indices including stream length‐gradient index, mountain front sinuosity, valley floor width to valley height ratios, and entrenchment of recent alluvial fan deposits were used to define the lateral growth and direction of propagation of the Spinatizha fault. Left‐lateral displacement along Chaman fault and uplift along the Spinatizha fault was defined using topographic analysis of the Roghani ridge and geomorphic mapping of an impressive alluvial fan, the Bostankaul fan. The landforms and structures record slip partitioning along the Indian plate boundary, and account for the convergence resulting from the difference in the Chaman fault azimuth and orientation of the velocity vector of the Indian plate. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
50.
Groundwater is a major source of water supply for domestic and irrigation uses in semiarid, remote but rapidly developing Kilasaifullah district part of Zhob River Basin, located at Pakistan–Afghanistan Border. Zhob River is among few major rivers of perennial nature in Balochistan, which flows from WSW to ENE and falls in Gomal River, a tributary of Indus River. Keeping in view the important geopolitical position and rapid development of the region, this study is primarily focused on groundwater chemistry for contamination sources as well as agriculture development. Water samples from open and tube wells are analyzed and calculated for electrical conductivity (EC), total dissolved solids (TDS), turbidity, pH, K+, Na+, Ca2+, Mg2+, HCO, Cl?, NO, SO, PO, sodium percent (Na%), sodium adsorption ratio (SAR), Kelly's index (KI), and heavy metals (Fe, Cu, Cr, Zn, Pb, and Mn). On the basis of the chemical constituents two zones within the study area are identified and possible causes of the contaminants are pointed out. Two recharge areas were responsible for the different chemical results in groundwater, e.g., zone A was recharged from NNW saline geological formations (Nisai, Khojak, Multana, Bostan formations, and Muslim Bagh ophiolites), which are concentrated with high sodium and chloride. On the other hand Zone B was sourced from SSW from carbonate rich rocks (Alozai, Loralai, Parh formations, and Muslim Bagh ophiolites). The groundwater is classified as C2–S1, C3–S1, C3–S2, C4–S2 on the basis of EC and SAR values which indicate that most of the water of both zones can be used for irrigation safely except the samples plotted in C3–S2 and C4–S2 categories which could be dangerous for soil and crops. Groundwater samples are plotted in good to permissible limits with some samples excellent to good and few samples belong to doubtful category based on sodium percent. Groundwater of zone A is unsuitable for irrigation use due to higher values of KI (more than one) but water of zone B are good for irrigation based on KI. In general, water of both zones is suitable for irrigation but care should be taken during the selection of crops which are sensitive to alkalinity or sodium hazards particularly in zone A.  相似文献   
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