Heterogeneous data management and modeling for the gravimetric geoid model: a review study in Pakistan     

Sadiq  Muhammad  Ahmad  Zulfiqar 《Arabian Journal of Geosciences》2015,8(4):2247-2263

Arabian Journal of Geosciences - The gravimetric geoid model can be used as vertical reference in surveying and other related technologies. It is being developed by NESCOM in collaboration with the...  相似文献   

A case study of Precambrian to Eocene sediments’ hydrocarbon potential assessment in Central Indus Basin of Pakistan     

Shazia Asim  Peimin Zhu  Shahid Nadeem Qureshi  Muhammad Tayyab Naseer 《Arabian Journal of Geosciences》2015,8(12):10339-10357

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Aggregative effect on rice production due to climate change using index number under indeterminate environment: a case study from Punjab,Pakistan     

Aslam  Muhammad 《Theoretical and Applied Climatology》2022,147(1-2):283-290

Theoretical and Applied Climatology - The existing Laspeyres index, Paasche’s index, and Fisher’s index under classical statistics cannot be applied when observations are indeterminate,...  相似文献   

Primordial magnetic fields in the f2FF model in large field inflation under de Sitter and power law expansion     

A. S. Al Muhammad  R. Lopez‐Mobiia 《Astronomische Nachrichten》2016,337(3):318-328

We use the f²FF model to study the generation of primordial magnetic fields (PMF) in the context of large field inflation (LFI), described by the potential, V ∼ Mϕ^p. We compute the magnetic and electric spectra for all possible values of the model parameters under de Sitter and power law expansion. We show that scale invariant PMF are not obtained in LFI to first order in the slow roll approximation, if we impose the constraint V (ϕ = 0) ∼ 0. Alternatively, if these constraints are relaxed, the scale invariant PMF can be generated. The associated electric field energy can fall below the energy density of inflation, ρ_Inf for the ranges of comoving wavenumbers, k > 8 × 10^–7 Mpc^–1 and k > 4 × 10^–6 Mpc^–1 in de Sitter and power law (PL) expansion. Further, it can drop below ρ_Inf on the ranges, e‐foldings N > 51, p < 1.66, p > 2.03, l₀ > 3 × 10⁵ M_Pl^–1(H_i < 3.3 × 10^–6 M_Pl), and M > 2.8 × 10^–3 M_Pl. All of the above ranges fit with the observational constraints. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

Depositional Environment and Lithofacies Analyses of Eocene Lacustrine Shale in the Bohai Bay Basin: Insights from Mineralogy and Elemental Geochemistry     

Danish KHAN  LIANG Chao  QIU Longwei  Kamran MIRZA  WANG Yelei  Muhammad KASHIF  Saif Ur REHMAN  WANG Yuzhe  TENG Jianbin 《《地质学报》英文版》2023,97(2):589-609

The effect of various depositional parameters including paleoclimate, paleosalinity and provenance, on the depositional mechanism of lacustrine shale is very important in reconstructing the depositional environment. The classification of shale lithofacies and the interpretation of shale depositional environment are key features used in shale oil and gas exploration and development activity. The lower 3^rd member of the Eocene Shahejie Formation(Es₃^x shale) was sel...  相似文献   

Influence of drainage and root biomass on soil mechanical behavior in triaxial tests     

Alam  Mehtab  Jiang  Yuan-Jun  Umar  Muhammad  Su  Li-jun  Rahman  Mahfuzur  Ullah  Faheem 《Acta Geotechnica》2022,17(7):2875-2893

Acta Geotechnica - This paper presents a study in which triaxial tests were performed on loess soil reinforced with natural roots. Triaxial compression tests were performed on soil specimens with...  相似文献   

Evaluation of remote sensing‐based seismic site characterization using earthquake damage data     

Muhammad Shafique  Mark van der Meijde  Harald M. A. van der Werff 《地学学报》2012,24(2):123-129

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Assessing Carbon Stock and Sequestration of the Tropical Seagrass Meadows in Indonesia     

Wahyudi  A’an J.  Rahmawati  Susi  Irawan  Andri  Hadiyanto  Hadiyanto  Prayudha  Bayu  Hafizt  Muhammad  Afdal  Afdal  Adi  Novi S.  Rustam  Agustin  Hernawan  Udhi. E.  Rahayu  Yusmiana P.  Iswari  Marindah Y.  Supriyadi  Indarto H.  Solihudin  Tubagus  Ati  Restu Nur Afi  Kepel  Terry L.  Kusumaningtyas  Mariska A.  Daulat  August  Salim  Hadiwijaya L.  Sudirman  Nasir  Suryono  Devi D.  Kiswara  Wawan 《Ocean Science Journal》2020,55(1):85-97

Ocean Science Journal - Seagrass meadows provide critical ecosystem services for coastal areas, e.g., as nursery habitats for various fish species, help with water filtration of suspended sediment,...  相似文献   

A wavelet based approach for combining the outputs of different rainfall–runoff models     

Muhammad?ShoaibEmail author  Asaad?Y.?Shamseldin  Sher?Khan  Mudasser?Muneer?Khan  Zahid?Mahmood?Khan  Bruce?W.?Melville 《Stochastic Environmental Research and Risk Assessment (SERRA)》2018,32(1):155-168

The rainfall–runoff modelling being a stochastic process in nature is dependent on various climatological variables and catchment characteristics and therefore numerous hydrological models have been developed to simulate this complex process. One approach to modelling this complex non-linear rainfall–runoff process is to combine the outputs of various models to get more accurate and reliable results. This multi-model combination approach relies on the fact that various models capture different features of the data, and hence combination of these features would yield better result. This study for the first time presented a novel wavelet based combination approach for estimating combined runoff The simulated daily output (Runoff) of five selected conventional rainfall–runoff models from seven different catchments located in different parts of the world was used in current study for estimating combined runoff for each time period. Five selected rainfall–runoff models used in this study included four data driven models, namely, the simple linear model, the linear perturbation model, the linearly varying variable gain factor model, the constrained linear systems with a single threshold and one conceptual model, namely, the soil moisture accounting and routing model. The multilayer perceptron neural network method was used to develop combined wavelet coupled models to evaluate the effect of wavelet transformation (WT). The performance of the developed wavelet coupled combination models was compared with their counterpart simple combination models developed without WT. It was concluded that the presented wavelet coupled combination approach outperformed the existing approaches of combining different models without applying input WT. The study also recommended that different models in a combination approach should be selected on the basis of their individual performance.  相似文献   

Geophysical Investigation of Fresh‐Saline Water Interface: A Case Study from South Punjab,Pakistan          下载免费PDF全文

Muhammad Hasan  Yanjun Shang  Gulraiz Akhter  Majid Khan 《Ground water》2017,55(6):841-856

The importance of the study of fresh‐saline water incursion cannot be over‐emphasized. Borehole techniques have been widely used, but they are quite expensive, intrusive, and time consuming. The electrical resistivity method has proved very successful in groundwater assessment. This advanced technique uses the calculation of Dar‐Zarrouk (D‐Z) parameters, namely longitudinal unit conductance, transverse unit resistance, and longitudinal resistivity has been employed by using 50 vertical electrical sounding points to assess the groundwater and delineate the fresh‐saline water interface over 1045 km² area of Khanewal in Southern Punjab of Pakistan. The x‐y plots and maps of D‐Z parameters were produced to establish a decipherable vision for the occurrence and distribution of different water‐bearing formations of fresh‐saline water aquifers through a complicated situation of intermixing of different resistivity ranges for fresh‐saline water bodies. This technique is useful to reduce the ambiguity produced by the process of equivalence and suppression which cause intermixing in differentiating fresh, brackish, and saline aquifers during interpretation. The fresh‐saline water interface is correlated very well with the previous studies of water quality analysis carried out in Khanewal area. The results suggest that the D‐Z parameters are useful for demarcating different aquifer zones. The behavior and pattern of D‐Z parameters with respect to occurrence and distribution of different water‐bearing formations were effectively identified and delineated in the study area.  相似文献