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91.
新疆干旱区绿洲土壤盐渍化信息提取对比研究 总被引:2,自引:0,他引:2
在遥感影像分类的过程中非光谱特征起着重要的辅助作用。纹理特征作为一种重要的非光谱特征对于遥感影像分类精度的提高也有很重要的作用。以渭干河-库车河三角洲绿洲为例,利用ETM+数据,探讨了该绿洲盐渍化土地覆盖信息的提取方法。提出了基于SVM的光谱和纹理两种信息复合的分类方法,通过此方法对该绿洲进行分类研究,并将分类结果与最小距离法、最大似然法(MLC)、神经网络法(Neural net)和单源数据(光谱)SVM分类结果进行定性和定量比较分析。研究结果表明:该方法能够有效地解决单数据源分类效果破碎、分类精度不高等问题,并对高维输入向量具有较高的推广能力。总精度达到93.179 5%,比单源信息的SVM分类法提高了3.161 8%,比最大似然法提高了4.825 2%,比神经网络法提高了7.475 6%,而与最小距离法相比,总精度甚至提高了11.102 9%,取得了良好的效果。与传统的分类方法的比较表明,文中所提出的分类方法具有明显的优越性和良好的前景,因此该方法更适合于遥感图像分类和盐渍化信息提取,是地物遥感信息提取的有效途径。 相似文献
92.
Muhammad Ashraf Amir Abbas Saqib Zia Yu-Ming Chu Ilyas Khan Kottakkaran Sooppy Nisar 《计算机、材料和连续体(英文)》2020,65(2):1809-1823
The present study is concerned with the physical behavior of the combined
effect of nano particle material motion and heat generation/absorption due to the effect of
different parameters involved in prescribed flow model. The formulation of the flow
model is based on basic universal equations of conservation of momentum, energy and
mass. The prescribed flow model is converted to non-dimensional form by using suitable
scaling. The obtained transformed equations are solved numerically by using finite
difference scheme. For the analysis of above said behavior the computed numerical data
for fluid velocity, temperature profile, and mass concentration for several constraints that
is mixed convection parameter λt, modified mixed convection parameter λc, Prandtl
number Pr, heat generation/absorption parameter δ, Schmidt number Sc, thermophoresis
parameter Nt, and thermophoretic coefficient k are sketched in graphical form. Numerical
results for skin friction, heat transfer rate and the mass transfer rate are tabulated for
various emerging physical parameters. It is reported that in enhancement in heat,
generation boosts up the fluid temperature at some positions of the surface of the sphere.
As heat absorption parameter is decreased temperature field increases at position X = π/4
on the other hand, no alteration at other considered circumferential positions is noticed. 相似文献
93.
Dolat Khan Gohar Ali Arshad Khan Ilyas Khan Yu-Ming Chu Kottakkaran Sooppy Nisar 《计算机、材料和连续体(英文)》2020,65(2):1237-1251
Nowadays some new ideas of fractional derivatives have been used
successfully in the present research community to study different types of mathematical
models. Amongst them, the significant models of fluids and heat or mass transfer are on
priority. Most recently a new idea of fractal-fractional derivative is introduced; however,
it is not used for heat transfer in channel flow. In this article, we have studied this new
idea of fractal fractional operators with power-law kernel for heat transfer in a fluid flow
problem. More exactly, we have considered the free convection heat transfer for a
Newtonian fluid. The flow is bounded between two parallel static plates. One of the
plates is heated constantly. The proposed problem is modeled with a fractal fractional
derivative operator with a power-law kernel and solved via the Laplace transform method
to find out the exact solution. The results are graphically analyzed via MathCad-15
software to study the behavior of fractal parameters and fractional parameter. For the
influence of temperature and velocity profile, it is observed that the fractional parameter
raised the velocity and temperature as compared to the fractal operator. Therefore, a
combined approach of fractal fractional explains the memory of the function better than
fractional only. 相似文献
94.
Operation and control of a water supply system 总被引:1,自引:0,他引:1
The control of water supply systems is becoming more important, since there are increasing requirements to improve operation. A need exists to model and simulate water supply systems so that their behavior can be fully understood and the total process optimized. This paper describes the simulation and control of a water supply system consisting of a sequence of pumping stations that deliver water through pipelines to intermediate storage reservoirs. The system is represented by dominant system variables that represent active and passive dynamical elements. The hydraulic models include the nonlinear coupling between flow rates and reservoir heads. The bisection numerical solution approach is used to obtain a roughness dependent friction coefficient. The whole system is simulated and the results are presented and compared with the real-time measured data. A water level controller using the robust polynomial H(infinity) optimization method by manipulating pump speed is obtained. The stochastic nature of the disturbance and loads is considered for controller design. The parametrized dynamic weighting functions of the design theory are selected to achieve the required control functions and robustness. 相似文献
95.
Abid. A. Memon M. Asif Memon Kaleemullah Bhatti Kamsing Nonlaopon Ilyas Khan 《计算机、材料和连续体(英文)》2022,70(3):4341-4355
This article is intended to examine the fluid flow patterns and heat transfer in a rectangular channel embedded with three semi-circular cylinders comprised of steel at the boundaries. Such an organization is used to generate the heat exchangers with tube and shell because of the production of more turbulence due to zigzag path which is in favor of rapid heat transformation. Because of little maintenance, the heat exchanger of such type is extensively used. Here, we generate simulation of flow and heat transfer using non-isothermal flow interface in the Comsol multiphysics 5.4 which executes the Reynolds averaged Navier stokes equation (RANS) model of the turbulent flow together with heat equation. Simulation is tested with Prandtl number (Pr = 0.7) with inlet velocity magnitude in the range from 1 to 2 m/sec which generates the Reynolds number in the range of 2.2 × 105 to 4.4 × 105 with turbulence kinetic energy and the dissipation rate in ranges (3.75 × 10−3 to 1.5 × 10−2) and (3.73 × 10−3−3 × 10−2) respectively. Two correlations available in the literature are used in order to check validity. The results are displayed through streamlines, surface plots, contour plots, isothermal lines, and graphs. It is concluded that by retaining such an arrangement a quick distribution of the temperature over the domain can be seen and also the velocity magnitude is increasing from 333.15% to a maximum of 514%. The temperature at the middle shows the consistency in value but declines immediately at the end. This process becomes faster with the decrease in inlet velocity magnitude. 相似文献
96.
Deep transfer learning in human–robot interaction for cognitive and physical rehabilitation purposes
Ilyas Chaudhary Muhammad Aqdus Rehm Matthias Nasrollahi Kamal Madadi Yeganeh Moeslund Thomas B. Seydi Vahid 《Pattern Analysis & Applications》2022,25(3):653-677
Pattern Analysis and Applications - This paper presents the extraction of the emotional signals from traumatic brain-injured (TBI) patients through the analysis of facial features and... 相似文献
97.
Ilyas S. Nizamov Yevgeniy N. Nikitin Ilnar D. Nizamov Rafael A. Cherkasov 《Journal of Sulfur Chemistry》2016,37(2):189-195
Bis(trimethylsilyl) esters of bisaryldithiophosphonic acids were obtained in 70–81% yields by the reactions of 2,4-diaryl 1,3,2,4-dithiadiphospheta ne-2,4-disulfides with 1,3-bis(trimethylsilyloxy)benzene and 2-methyl 1,3-bis(trimethylsilyloxy)benzene. 相似文献
98.
Emerging database applications require the use of new indexing structures beyond B-trees and R-trees. Examples are the k-D tree, the trie, the quadtree, and their variants. They are often proposed as supporting structures in data mining, GIS, and CAD/CAM applications. A common feature of all these indexes is that they recursively divide the space into partitions. A new extensible index structure, termed SP-GiST is presented that supports this class of data structures, mainly the class of space partitioning unbalanced trees. Simple method implementations are provided that demonstrate how SP-GiST can behave as a k-D tree, a trie, a quadtree, or any of their variants. Issues related to clustering tree nodes into pages as well as concurrency control for SP-GiST are addressed. A dynamic minimum-height clustering technique is applied to minimize disk accesses and to make using such trees in database systems possible and efficient. A prototype implementation of SP-GiST is presented as well as performance studies of the various SP-GiST's tuning parameters. 相似文献
99.
Food Science and Biotechnology - In this study, the effects of encapsulation with maltodextrin and reconstituted skim milk (RSM) and their binary and ternary blends with gum arabic (GA) by spray... 相似文献
100.
Example-Based Machine Translation (EBMT) is a corpus based approach to Machine Translation (MT), that utilizes the translation
by analogy concept. In our EBMT system, translation templates are extracted automatically from bilingual aligned corpora by
substituting the similarities and differences in pairs of translation examples with variables. In the earlier versions of
the discussed system, the translation results were solely ranked using confidence factors of the translation templates. In
this study, we introduce an improved ranking mechanism that dynamically learns from user feedback. When a user, such as a
professional human translator, submits his evaluation of the generated translation results, the system learns “context-dependent
co-occurrence rules” from this feedback. The newly learned rules are later consulted, while ranking the results of the subsequent
translations. Through successive translation-evaluation cycles, we expect that the output of the ranking mechanism complies
better with user expectations, listing the more preferred results in higher ranks. We also present the evaluation of our ranking
method which uses the precision values at top results and the BLEU metric. 相似文献