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1.
The Journal of Supercomputing - Deep learning algorithms have yielded remarkable results in medical diagnosis and image analysis, besides their contribution to improvements in a number of fields... 相似文献
2.
3.
Mustafa Ayhan Erkan Topal 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2005,20(1):81-87
Tunneling projects have their uniqueness in terms of engineering problems. The expertise gained from analyzing these projects establishes a sound basis for future application. This paper conveys experiences gained during the construction and support of the design of the Dicle–Kralkizi water tunnel, Turkey. Tunnel stability problems including overbreaks and surface subsidence are evaluated. An analysis of the breakdowns, factors controlling advance rate and the overall performance of tunnel are covered. The accumulated information presented here is believed to be useful and reliable for a successful tunnel excavation in similar formations. 相似文献
4.
ChukFong Ho Masrah Azrifah Azmi Murad Shyamala Doraisamy Rabiah Abdul Kadir 《Artificial Intelligence Review》2014,42(4):851-894
Recent advances in natural language processing have increased the popularity of paraphrase extraction. Most of the attention, however, has been focused on the extraction methods only without taking the resource factor into the consideration. Unknowingly, there is a strong relationship between them and the resource factor also plays an equally important role in paraphrase extraction. In addition, almost all of the previous studies have been focused on corpus-based methods that extract paraphrases from corpora based solely on syntactic similarity. Despite the popularity of corpus-based methods, a considerable amount of research has consistently shown that these methods are vulnerable to several types of erroneous paraphrases. For these reasons, it is necessary to evaluate whether the trend is moving in a positive direction. This paper reviews the major research on paraphrase extraction methods in detail. It begins by exploring the definition of paraphrase from different perspectives to provide a better understanding of the concept of paraphrase extraction. It then studies the characteristics and potential uses of different types of paraphrase resources. After that, it divides paraphrase extraction methods into four main categories: heuristic-based, knowledge-based, corpus-based and hybrid-based and summarizes their strengths and weaknesses. This paper concludes with some potential open research issues for future directions. 相似文献
5.
L. O. A. N. Ramadhan La Agusu Laode A. Kadir R. Saputra F. Nurdin 《Polymer-Plastics Technology and Engineering》2020,59(12):1277-1283
ABSTRACTPolyelectrolyte complex (PEC) of chitosan (Chi) and poly (acrylic acid) (PAA)-modified iron sand leachate were prepared and considered for applicability as a proton exchange membrane in fuel cells. Chi-PAA-hematite blended in different weight ratios and the resulting membranes were treated to enable the formation of the polyelectrolyte. The membranes of Chi-PAA polyblend were treated using iron sand leachate and reveal high ion exchange capacity (IEC), proton conductivity, water uptake, and good mechanical stability. The result of research indicated that the membrane with 40 wt% of Chi and 60 wt% of PAA blend which its conductivity of 6.10 × 10?2 S cm?1 was potentially for a proton exchange membrane in fuel cell applications. 相似文献
6.
Saliency, Scale and Image Description 总被引:6,自引:0,他引:6
7.
Soil-water distribution in homogeneous soil profiles of Yolo clay loam and Yolo sand (Typic xerorthents) irrigated from a circular source of water, was measured several times after the initiation of irrigation. The effect of trickle discharge rates and soil type on the locations of the wetting front and soil-water distribution was considered. Soil-water tension and hydraulic conductivity, as functions of soil-water content, were also measured. The theories of time-dependent, linearized infiltration from a circular source and a finite-element solution of the two-dimensional transient soil-water equation were compared with the experimental results. In general, for both soils the computer horizontal and vertical advances of the wetting front were closely related to those observed. With both theories, a better prediction of the wetting front position for the clay loam soil than for the sandy soil is shown. The calculated and measured horizontal vertical advances did not agree over long periods of time. With the linearized solution, overestimated and underestimated vertical advances for the clay and sandy soils, respectively, were shown. The finite-element model approximate in a better way the vertical advances than the linearized solution, while an opposite tendency for the horizontal advances indicated, especially in sandy soil.Notation
k
constant (dK/d)
-
K
hydraulic conductivity
-
K
0
saturated hydraulic conductivity
-
J
0,J
1
Bessel functions of the first kind
-
h
soil water tension
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q
Q/r
0
2
-
Q
discharge rate
-
r
cylindrical coordinate; also horizontal distance in soil surface
-
R
dimensionless quantity forr
-
r
0
constant pond radius
-
R
0
dimensionless quantity forr
0
-
t
time
-
T
dimensionless quantity fort
-
x, y
Cartesian coordinates
-
z
vertical coordinate; also vertical distance along thez axis chosen positively downward
-
Z
dimensionless quantity forz
-
empirical soil characteristic constant
-
dummy variable of integration
-
volumetric soil water content
-
matrix flux potential
-
dimensionless quantity for 相似文献
8.
Erkan Yuce Shahram Minaei Oguzhan Cicekoglu 《Electrical Engineering (Archiv fur Elektrotechnik)》2006,88(6):519-525
In this paper, new floating immittance function simulators employing second-generation current controlled conveyors are proposed.
The first four of the presented circuits employ only a single grounded capacitor as passive component and can realize either
a negative or a positive floating inductor or capacitor. The last two of the proposed circuits do not employ passive components
and can realize either negative or positive floating resistances. All of the proposed circuits do not require passive element
matching. As an application, a third-order butterworth filter is realized using the proposed positive floating inductance
simulator. SPICE simulation results and large signal behavior of the filter are included. 相似文献
9.
10.
The paper deals with the singularly perturbed quasilinear initial value problem exhibiting initial layer. First the nature of solution of differential problem before presenting method for its numerical solution is discussed. The numerical solution of the problem is performed with the use of a finite-fitted difference scheme on an appropriate piecewise uniform mesh (Shishkin-type mesh). An error analysis shows that the method is first-order convergent except for a logarithmic factor, in the discrete maximum norm, independently of the perturbation parameter. Finally, numerical results supporting the theory are presented. 相似文献