Estimation of glacier ice-thickness distribution is important for many glacio-hydrological applications such as runoff projections, glacial lake outburst flood (GLOF) predictions, future evolution of glaciers. Varieties of modelling approaches are available for estimating ice-thickness distribution depending upon the data availability. In the present study, we estimated the ice-thickness distribution and total ice volume of Chhota Shigri Glacier using an optimally parameterized Glacier Bed Topography version 2 (GlabTop2) model, a shallow ice approximation (SIA)-based spatially distributed approach. Among the model input parameters, the shape factor (f), a non-measurable factor compensating for unaccounted effects such as valley shape needs to be calibrated using field measurements of ice-thickness. However, the lack of direct measurements of ice-thickness over many glaciers worldwide restricts model calibration and effective implementation. Therefore, to overcome this limitation, in this study, a novel approach using a relationship between shape factor, glacier cross-sectional width, and ice-thickness at the centre of a cross-section has been proposed and also tested to estimate optimal shape factor of the study glacier. Additionally, a detailed analysis of the effect of Digital Elevation Model (DEM) resolution and shape factor parameterization on the modelled ice-thickness estimates indicate that improving either the DEM resolution or calibrating the shape factor individually will not lead to improved ice-thickness estimates. In fact, both are necessary for better estimation of ice-thickness distribution. The high resolution DEM used in this study is TerraSAR-X add-on for Digital Elevation Measurement (TanDEM-X) DEM of 10 × 10 m grid size. Finally, a comparison of the results from a previous study where they used Shuttle Radar Topography Mission (SRTM) 90 m DEM indicates that the improved parameterisation of GlabTop2 model has led to a reduction in the error bounds of the estimated ice-thickness including the total glacier stored ice volume for the year 2013, which is estimated to be 1.74 ± 0.25 km3. Furthermore, based on the obtained results, it can be said that the GlabTop2 model combined with the proposed parameterization approach is having enormous potential to be applied over the wide range of data scarce Himalayan glaciers to quantify reliable ice-thickness estimates. 相似文献
The effects of the anionic surfactant on the morphology, size and crystallization of NiSe precipitated from NiCl2·6H2O and SeCl4 in presence of hydrazine (N2H4·H2O) as reductant were investigated. The products have been successfully synthesized in presence of sodium dodecyl benzene sulfonate (SDBS) as surfactant via an improved hydrothermal route. A variety of synthesis parameters, such as reaction time and temperature, capping agent and amount of reducing agent have a significant effect on the particle size, phase purity and morphology of the obtained products. The sample size became bigger with decreasing reaction temperature and increasing reaction time. In the presence of 2 ml hydrazine, the samples were found to be the mixture of Ni3Se2 and NiSe. With increasing the reaction time and amount of hydrazine a pure phase of hexagonal NiSe was obtained. X-ray diffraction analysis (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM) images indicate phase, particle size and morphology of the products. Chemical composition and purity of the products were characterized by X-ray energy dispersive spectroscopy (EDS). Photoluminescence (PL) was used to study the optical properties of NiSe samples. 相似文献
In material engineering application, the failure time of material due to weakness in material (fatigue) is usually caused by repeated variations of stress. The failure time is modeled by statistical distributions. In this article, an attribute multiple state repetitive group sampling plan is developed assuming that the life time follows the Burr Type XII distribution. The plan parameters are determined by considering two points on operating characteristic (OC) curve. Tables are given for the practical use. The advantages of the proposed plan are discussed over the single sampling plans. Examples are given to illustrate the proposed plan. 相似文献
This work investigates radiofrequency shielding by polypyrrole (PPy)-coated fibrous mats consisting of nano and regular fibers.
Radiofrequency shielding protects human beings as well as electronic devices from the harmful effects of radiofrequency waves.
The results of this study show that, generally, lowering the fiber diameter of the coated mats increases the reflection but
decreases the absorption of radiofrequency radiation in the range of 5 GHz to 8 GHz. Moreover, absorption of higher frequencies
is greater than that of lower frequencies, whereas for reflection the opposite trend is observed. The sum of absorption and
reflection of radiofrequencies in the range of 5 GHz to 8 GHz by PPy-coated mats is not affected by the fiber diameter of
the mats. PPy-coated regular poly(acrylonitrile) (PAN) and poly(ethylene terephthalate) (PET) fiber mats with weight per unit
area of 16.67 mg/cm2 provide radiofrequency shielding above 85%. Nanofibrous mats with weight per unit area of nearly 60 times less showed similar
radiofrequency shielding effectiveness as regular fiber mats, highlighting the importance of the high specific surface area
of nanofibers. 相似文献
In this research work, substituted tin and vanadium garnets Y2.5Bi0.5Fe2?2xSnxFe3?xVx O12 (0?≤?x?≤?0.2) were prepared by mechanochemical processing following with 10 h milling and post-annealing at different temperatures. Physical properties of samples were studied by X-ray diffraction analysis (XRD), Far-infrared spectroscopy (Far-IR), and field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), and vibrating sample magnetometer (VSM). XRD patterns of prepared garnets show that the samples are all single phase with garnet structure at 900 °C. Further, the average crystallite size was calculated by Debye–Scherrer, and Williamson–Hall methods. We also studied the magnetic properties of prepared samples by using a vibrating sample magnetometer (VSM). Experiments showed that the maximum value of vanadium that can be entered in the garnet structure is 0.2.
Several toxic compounds are known to induce apoptosis in mammalian cell lines. The human neuroblastoma
cells (SH-SY5Y) were exposed to the phosphatase inhibiting toxin okadaic acid (OA) or hydrogen peroxide (H2O2)
to induce apoptosis as well as generate reactive oxygen species (ROS). Mitoxantrone (MXT) was used as a positive
control for apoptosis. The SH-SY5Y cells were transfected with eukaryotic expression plasmid pHyPer-dMito encoding
mitochondrial-targeted fluorescent or pHyPer-dCito encoding cytoplasmic-targeted fluorescent sensor for hydrogen
peroxide (HyPer). The ERp57, also called GRP58 (Glucose-regulated protein 58), is a stress protein induced in
conditions like glucose starvation and viral infection. Recently ERp57 was shown to translocate from the endoplasmatic
reticulum to the cell surface in anthracycline-induced apoptotic cells. ERp57 co-translocation together with calreticulin
has been suggested to be crucial for recognizing tumor cells to induce immunogenic cell death. ERp57 translocation
after exposure to okadaic acid was studied using immunofluorescence and confocal microscopy. These studies indicated
that okadaic acid has induced the translocation of ERp57 to the cellular membrane. 相似文献
In this paper, with respect to reviewing and comparing existing social networks’ datasets, we introduce SNEFL dataset: the first social network dataset that includes the level of users’ likes (fuzzy like) data in addition to the likes between users. With users’ privacy in mind, the data has been collected from a social network. It includes several additional features including age, gender, marital status, height, weight, educational level and religiosity of the users. We have described its structure, analysed its features and evaluated its advantages in comparison with other social network datasets. On top of that, using unique feature of SNEFL dataset (fuzzy like) for the first time a rule-based algorithm has been developed to detect involuntary celibates (Incels) in social networks. Despite Incels activities in online social networks, until now no study on computer science has been performed to identify them. This study is the first step to address this challenge that society is facing today. Experimental results show that the accuracy of the proposed algorithm in identifying Incels among all social network users is 23.21% and among users who have fuzzy like data is 68.75%. In addition to the Incel detection, SNEFL dataset can be used by researchers in different fields to produce more accurate results. Some study areas that SNEFL dataset can be used in are network analysis, frequent pattern mining, classification and clustering.
Recently, the world is facing the terror of the novel corona-virus, termed as COVID-19. Various health institutes and researchers are continuously striving to control this pandemic. In this article, the SEIAR (susceptible, exposed, infected, symptomatically infected, asymptomatically infected and recovered) infection model of COVID-19 with a constant rate of advection is studied for the disease propagation. A simple model of the disease is extended to an advection model by accommodating the advection process and some appropriate parameters in the system. The continuous model is transposed into a discrete numerical model by discretizing the domains, finitely. To analyze the disease dynamics, a structure preserving non-standard finite difference scheme is designed. Two steady states of the continuous system are described i.e., virus free steady state and virus existing steady state. Graphical results show that both the steady states of the numerical design coincide with the fixed points of the continuous SEIAR model. Positivity of the state variables is ensured by applying the M-matrix theory. A result for the positivity property is established. For the proposed numerical design, two different types of the stability are investigated. Nonlinear stability and linear stability for the projected scheme is examined by applying some standard results. Von Neuman stability test is applied to ensure linear stability. The reproductive number is described and its pivotal role in stability analysis is also discussed. Consistency and convergence of the numerical model is also studied. Numerical graphs are presented via computer simulations to prove the worth and efficiency of the quarantine factor is explored graphically, which is helpful in controlling the disease dynamics. In the end, the conclusion of the study is also rendered. 相似文献