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Seismic performance analysis and design suggestion for frame buildings with cast-in-place staircases 被引量:2
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作者 Feng Yuan Wu Xiaobin +2 位作者 Xiong Yaoqing Li Congchun Yang Wen 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第2期209-219,共11页
Many staircases in reinforced concrete (RC) frame structures suffered severe damage during the Wenchuan earthquake. Elastic analyses for 18 RC structure models with and without staircases are conducted and compared ... Many staircases in reinforced concrete (RC) frame structures suffered severe damage during the Wenchuan earthquake. Elastic analyses for 18 RC structure models with and without staircases are conducted and compared to study the influence of the staircase on the stiffness, displacements and internal forces of the structures. To capture the yielding development and damage mechanism of frame structures, elasto-plastic analysis is carried out for one of the 18 models. Based on the features observed in the analyses, a new type of staircase design i.e., isolating them from the master structure to eliminate the effect of K-type struts, is proposed and discussed. It is concluded that the proposed method of staircase isolation is effective and feasible for engineering design, and does not significantly increase the construction cost. 展开更多
关键词 cast-in-place staircases frame structure seismic performance design suggestions
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Improving the Seismic Performance of Staircases in Building Structures with a Novel Isolator
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作者 Yafei Zhang Ping Tan +1 位作者 Haitao Ma Marco Donà 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第8期415-431,共17页
A staircase provides the main escape way from a building in an emergency.Unfortunately,it may suffer severe damages or even collapse during an earthquake.For improving the seismic performance of staircases,this paper ... A staircase provides the main escape way from a building in an emergency.Unfortunately,it may suffer severe damages or even collapse during an earthquake.For improving the seismic performance of staircases,this paper proposes an innovative staircase isolator with the features of lightweight,costeffective and ease of construction and replacement,which is formed by suitable engineering plastic shims between rubber layers.A connection construction scheme is also proposed for the isolated staircase.Systematic performance tests have been carried out to characterize the isolator in terms of mechanic behavior and ultimate states.The test results show that mechanical properties of the proposed staircase isolator are excellent and suitable for staircase in building structure.In order to investigate the influence of staircase on building structural responses,time history analyses of a typical building structure without staircase(WS),with fixed staircase(FS)and with isolated staircase(IS)are conducted and compared within the environment of SAP2000.Results show that staircase isolation can effectively eliminate the diagonal bracing effect of staircase slab and make structural components uniformly stressed.When the novel isolator is employed for staircase in a building structure,there is no vulnerable position in staircase and the performance of staircase in building structure can be greatly enhanced. 展开更多
关键词 Seismic isolation seismic performance of staircases staircase isolation engineering-plastics rubber isolator rubber isolator
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Computerised Gate Firing Control for 17-Level MLI using Staircase PWM
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作者 M.Geetha R.Vijayabhasker Suresh Seetharaman 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期813-832,共20页
A basic 7-level MLI topology is developed and the same is extended to the 9-level then further increased to 17-levels.The developed structure minimizes the component’s count and size to draw out the system economy.De... A basic 7-level MLI topology is developed and the same is extended to the 9-level then further increased to 17-levels.The developed structure minimizes the component’s count and size to draw out the system economy.Despite the various advantages of MLIs,efficiency and reliability play a major role since the usage of components is higher for getting a low Total Harmonics Distortion(THD)value.This becomes a major challenge incorporated in boosting the efficiency without affecting the THD value.Various parametric observations are done and realized for the designed 9-level and 17-level MLI,being the Total Standing Voltage(TSV),efficiency,cost function per level count,and power loss.The respective parameters are compared with several existing and modern circuits and found to be effective in their performance.A novel single-phase 17-level asymmetrical Multi-Level Inverter(MLI)topology is developed to reduce the number of overall components.The developed topology generates 17-levels by using unequal DC sources.The developed MLI is proved under various tests con-ducted experimentally for the various loads like resistive,inductive,and combinational loads.A detailed comparison is done on several factors and represented graphically represented.Further,the proposed design provides a less TSV value is 6 V_(dc),efficiency is 94.21%and cost factor per level CF/L value for both values ofαis 2.01 and 2.05 and devices count with a low THD value 41.4%with respectively. 展开更多
关键词 INVERTERS 9-level and 17-level MLI switches count load current VOLTAGES round-robin staircase PWM
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V-Shaped Monopole Antenna with Chichena Itzia Inspired Defected Ground Structure for UWB Applications 被引量:7
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作者 Naeem Ahmad Jan Saad Hassan Kiani +4 位作者 Fazal Muhammad Daniyal Ali Sehrai Amjad Iqbal Muhammad Tufail Sunghwan Kim 《Computers, Materials & Continua》 SCIE EI 2020年第10期19-32,共14页
Due to rapid growth in wireless communication technology,higher bandwidth requirement for advance telecommunication systems,capable of operating on two or higher bands with higher channel capacities and minimum distor... Due to rapid growth in wireless communication technology,higher bandwidth requirement for advance telecommunication systems,capable of operating on two or higher bands with higher channel capacities and minimum distortion losses is desired.In this paper,a compact Ultra-Wideband(UWB)V-shaped monopole antenna is presented.UWB response is achieved by modifying the ground plane with Chichen Itzia inspired rectangular staircase shape.The proposed V-shaped is designed by incorporating a rectangle,and an inverted isosceles triangle using FR4 substrate.The size of the antenna is 25 mm×26 mm×1.6 mm.The proposed V-shaped monopole antenna produces bandwidth response of 3 GHz Industrial,Scientific,and Medical(ISM),Worldwide Interoperability for Microwave Access(WiMAX),(IEEE 802.11/HIPERLAN band,5G sub 6 GHz)which with an additional square cut amplified the bandwidth response up to 8 GHz ranging from 3.1 GHz to 10.6 GHz attaining UWB defined by Federal Communications Commission(FCC)with a maximum gain of 3.83 dB.The antenna is designed in Ansys HFSS.Results for key performance parameters of the antenna are presented.The measured results are in good agreement with the simulated results.Due to flat gain,uniform group delay,omni directional radiation pattern characteristics and well-matched impedance,the proposed antenna is suitable for WiMAX,ISM and heterogeneous wireless systems. 展开更多
关键词 V-shape MONOPOLE GAIN STAIRCASE ULTRA-WIDEBAND OMNI-DIRECTIONAL defected ground structure
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Observational analysis of the double-diffusive convection in the deep Canada Basin 被引量:2
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作者 XIE Lingling LI Mingming LI Min 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第11期71-79,共9页
The Canada Basin (CB) is the largest sub-basin in the Arctic, with the deepest abyssal plain of 3 850 m. The double-diffusive process is the possible passage through which the geothermal energy affects the above iso... The Canada Basin (CB) is the largest sub-basin in the Arctic, with the deepest abyssal plain of 3 850 m. The double-diffusive process is the possible passage through which the geothermal energy affects the above isolated deep waters. With the temperature-salinity-pressure observations in 2003, 500-m-thick transition layers and lower 1 000-m-thick bottom homogenous layers were found below 2 400 m in the central deep CB. Staircases with downward-increasing temperature and salinity are prominent in the transition layers, suggesting the double- diffusive convection in deep CB. The interface of the stairs is about 10 m thick with 0.001-0.002℃ temperature difference, while the thicknesses of the homogenous layers in the steps decrease upward from about 60 to 20 m. The density ratio in the deep central CB is generally smaller than 2, indicating stronger double-diffusive convection than that in the upper ocean of 200-400 m. The heat flux through the deepest staircases in the deep CB varies between 0.014 and 0.031 W/m2, which is one-two orders smaller than the upper double-diffusive heat flux, but comparable to the estimates of geothermal heat flux. 展开更多
关键词 double diffusion Canada Basin STAIRCASE heat flux water mass
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Novel image restoration model coupling gradient fidelity term based on adaptive total variation 被引量:1
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作者 石明珠 许廷发 +3 位作者 梁炯 冯亮 张坤 周立伟 《Journal of Beijing Institute of Technology》 EI CAS 2011年第2期261-266,共6页
A novel image restoration model coupling with a gradient fidelity term based on adaptive total variation is proposed in this paper. In order to choose proper parameters, the selection criteria were analyzed theoretica... A novel image restoration model coupling with a gradient fidelity term based on adaptive total variation is proposed in this paper. In order to choose proper parameters, the selection criteria were analyzed theoretically, and a simple scheme to demonstrate its validity was adopted experimentally. To make fair comparisons of performances of three models, the same numerical algorithm was used to solve partial differential equations. Both the international standard test image on Lena and HR image of CBERS-02B of Dalian city were used to verify the performance of the model. Experimental results illustrate that the new model not only preserved the edge and important details but also alleviated the staircase effect effectively. 展开更多
关键词 image restoration total variation(TV) gradient fidelity term staircase effect
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Fractional Fourier transform of Cantor sets: further numerical study
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作者 高穹 廖天河 崔远峰 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第6期2018-2022,共5页
This paper is a further work of the authors' paper published previously (Liao T H and Gao Q 2005 Chin. Phys. Lett. 22 2316). The amplitudes of fractional Fourier transform of Cantor sets are analysed from the viewp... This paper is a further work of the authors' paper published previously (Liao T H and Gao Q 2005 Chin. Phys. Lett. 22 2316). The amplitudes of fractional Fourier transform of Cantor sets are analysed from the viewpoint of multifractal by wavelet transform maxima method (WTMM). An integral operation is carried out before the application of WTMM, such that the function obtained can be considered as the perturbed devil staircase. Also, wavelets with large number of vanishing moments are used, which makes the complete singularity spectrum more accessible. The validity of multifractal formalism is guaranteed by restricting parameter q to a proper range, so that the phenomenon of multifractal phase transition can be explained reasonably. Particularly, the method of determining the range of parameter q in the above paper is developed to be more operational and rigorous. 展开更多
关键词 MULTIFRACTAL fractional Fourier transform wavelet transform perturbed devil staircase
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Nuclear-Magnetic-Resonance Properties of the Staircase Kagome Antiferromagnet PbCu3TeO7
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作者 代佳 王朋帅 +8 位作者 孙珊珊 庞斐 张金珊 董晓莉 乐艮 金魁 丛君状 孙阳 于伟强 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第12期143-146,共4页
We report the first nuclear magnetic resonance (NMR) study on single crystals of staircase Kagome antiferromagnet PbCu3Te07 (TN1 -36K). A Curie constant θ -140K is obtained by a Curie Weiss fit to the high- tempe... We report the first nuclear magnetic resonance (NMR) study on single crystals of staircase Kagome antiferromagnet PbCu3Te07 (TN1 -36K). A Curie constant θ -140K is obtained by a Curie Weiss fit to the high- temperature Knight shift of 125 Te. The hyperfine coupling constant is estimated to be 125Ahf = -67 kOe/#B, and a strong interlayer coupling among staircase Kagome planes is suggested with such a large hyperfine coupling, according to the lattice structure. The 63,65Cu NMR spectra are found by the zero-field (ZF) NMR at T = 2 K, and the internal hyperfine fields are estimated to be 10.3 T and 9.6 T, for Cu(1) and Cu(2) sites, respectively, in the lattice. A second type of ZF NMFt signal with a large rf enhancement is also seen after field-cycling through a high magnetic field. 展开更多
关键词 CU TE Nuclear-Magnetic-Resonance Properties of the Staircase Kagome Antiferromagnet PbCu3TeO7 NMR
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Study on tapered crossed subwavelength gratings by Fourier modal method
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作者 陈熙 钟源 +2 位作者 王青 张冶金 陈良惠 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期258-264,共7页
Fourier modal method incorporating staircase approximation is used to study tapered crossed subwavelength gratings in this paper. Three intuitive formulations of eigenvalue functions originating from the prototype are... Fourier modal method incorporating staircase approximation is used to study tapered crossed subwavelength gratings in this paper. Three intuitive formulations of eigenvalue functions originating from the prototype are presented, and their convergences are compared through numerical calculation. One of them is found to be suitable in modeling the diffraction efficiency of the circular tapered crossed subwavelength gratings without high absorption, and staircase approximation is further proven valid for non-highly-absorptive tapered gratings. This approach is used to simulate the "moth-eye" antireflection surface on silicon, and the numerical result agrees well with the experimental one. 展开更多
关键词 tapered crossed subwavelength gratings Fourier modal method staircase approximation eigenvalue functions
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Some minimax theorems with strictly monotone transformation
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作者 TANG Gu-sheng CHENG Cao-zong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第1期69-78,共10页
Some two-function minimax theorems are proved. In these results, the staircase and quantitative-topological conditions of both functions involve strictly monotone transformation and mixing of functional values. Conseq... Some two-function minimax theorems are proved. In these results, the staircase and quantitative-topological conditions of both functions involve strictly monotone transformation and mixing of functional values. Consequently, Lin Quan and Kindler's minimax theorems are generalized. 展开更多
关键词 minimax theorems STAIRCASE monotone transformation.
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Non-linear Invertible Maps that Preserve Staircase Subalgebras
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作者 ZHAO YAN-XIA XIA YU-LING 《Communications in Mathematical Research》 CSCD 2012年第3期265-274,共10页
Let g be the general linear Lie algebra consisting of all n x n matrices over a field F and with the usual bracket operation {x, y} =xy - yx. An invertible map φ : g →g is said to preserve staircase subalgebras if ... Let g be the general linear Lie algebra consisting of all n x n matrices over a field F and with the usual bracket operation {x, y} =xy - yx. An invertible map φ : g →g is said to preserve staircase subalgebras if it maps every staircase subalgebra to some staircase subalgebra of the same dimension. In this paper, we devote to giving an explicit description on the invertible maps on g that preserve staircase subalgebras. 展开更多
关键词 general linear Lie algebra staircase subalgebra non-linear map
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Effect of Acetone Vapor Smoothing Process on Surface Finish and Geometric Accuracy of Fused Deposition Modeling ABS Parts
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作者 Viviane Pestano Mariana Pohlmann Fabio Pinto da Silva 《Journal of Materials Science and Chemical Engineering》 CAS 2022年第10期1-9,共9页
FDM is a widely used additive manufacturing process, however, it has some limitations, such as surface finish, due to the staircase effect caused by the layer-by-layer deposition. Studies have been conducted on surfac... FDM is a widely used additive manufacturing process, however, it has some limitations, such as surface finish, due to the staircase effect caused by the layer-by-layer deposition. Studies have been conducted on surface finish of ABS parts with the use of acetone, but the process parameters and the resulting effects have not been fully investigated in the literature. Therefore, the aim of this study was to investigate the effects of acetone vapor smoothing process on surface finish and geometric accuracy of fused deposition modeling ABS parts. Specimens with different geometries were created and printed using two directions in different scales. The parts were exposed to acetone vapor for 20, 30 and 40 minutes. 3D deviation maps, roughness and microscopic analyses were conducted. The staircase effect was reduced at the expense of some geometric deviations, which varied according to the exposure time and part orientation. The smoothing process applied to the flat surfaces proved to be quite effective in reducing roughness by 90%, however, this reduction led to an undesirable rounding of the sharp edges. The results obtained in this study are consistent with those found in the literature and may help improve the quality of the ABS printed parts. 展开更多
关键词 Additive Manufacturing 3D Printing FDM Staircase Effect Acetone Vapor Polishing
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Adaptability of Conservative Staircase Scheme for Live Videos
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作者 Sudeep Kanav Satish Chand 《Circuits and Systems》 2011年第3期151-161,共11页
Existing broadcasting schemes provide services for the stored videos. The basic approach in these schemes is to divide the video into segments and organize them over the channels for proper transmission. Some schemes ... Existing broadcasting schemes provide services for the stored videos. The basic approach in these schemes is to divide the video into segments and organize them over the channels for proper transmission. Some schemes use segments as a basic unit, whereas the others require segments to be further divided into subsegments. In a scheme, the number of segments/subsegments depends upon the bandwidth allocated to the video by the video server. For constructing segments, the video length should be known. If it is unknown, then the segments cannot be constructed and hence the scheme cannot be applied to provide the video services. This is an important issue especially in live broadcasting applications wherein the ending time of the video is unknown, for example, cricket match. In this paper, we propose a mechanism for the conservative staircase scheme so that it can support live video broadcasting. 展开更多
关键词 CONSERVATIVE STAIRCASE SCHEME STAIRCASE SCHEME LIVE Video CHANNEL CHANNEL Transition
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Quantum Conductance Staircase of Edge Hole Channels in Silicon Quantum Wells
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作者 Nikolay T. Bagraev Leonid E. Klyachkin +1 位作者 Andrei A. Kudryavtsev Anna M. Malyarenko 《Journal of Modern Physics》 2012年第11期1771-1775,共5页
We present the findings for the quantum conductance staircase of holes that is caused by the edge channels in the ultra-shallow p-type silicon quantum well (Si-QW), 2 nm, confined by the δ-barriers heavily doped with... We present the findings for the quantum conductance staircase of holes that is caused by the edge channels in the ultra-shallow p-type silicon quantum well (Si-QW), 2 nm, confined by the δ-barriers heavily doped with boron on the n-type Si (100) surface. This longitudinal quantum conductance staircase, Gxx, is revealed by the voltage applied to the Hall contacts, Vxy, to a maximum of 4e2/h. In addition to the standard plateau, 2e2/h, the variations of the Vxy voltage appear to exhibit the fractional forms of the quantum conductance staircase with the plateaus and steps that bring into correlation respectively with the odd and even fractional values. 展开更多
关键词 Quantum CONDUCTANCE STAIRCASE EDGE CHANNELS Silicon Nanosandwich ODD and Even Fractional Values
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Finite-difference time-domain modeling of curved material interfaces by using boundary condition equations method
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作者 卢佳 周怀春 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第9期198-206,共9页
To deal with the staircase approximation problem in the standard finite-difference time-domain(FDTD) simulation,the two-dimensional boundary condition equations(BCE) method is proposed in this paper.In the BCE met... To deal with the staircase approximation problem in the standard finite-difference time-domain(FDTD) simulation,the two-dimensional boundary condition equations(BCE) method is proposed in this paper.In the BCE method,the standard FDTD algorithm can be used as usual,and the curved surface is treated by adding the boundary condition equations.Thus,while maintaining the simplicity and computational efficiency of the standard FDTD algorithm,the BCE method can solve the staircase approximation problem.The BCE method is validated by analyzing near field and far field scattering properties of the PEC and dielectric cylinders.The results show that the BCE method can maintain a second-order accuracy by eliminating the staircase approximation errors.Moreover,the results of the BCE method show good accuracy for cylinder scattering cases with different permittivities. 展开更多
关键词 finite-difference time-domain curved surface staircase error boundary condition equation
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A Variational Model for Removing Multiple Multiplicative Noises
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作者 Xuegang Hu Yan Hu 《Open Journal of Applied Sciences》 2015年第12期783-796,共14页
The problem of multiplicative noise removal has been widely studied in recent years. Many methods have been used to remove it, but the final results are not very excellent. The total variation regularization method to... The problem of multiplicative noise removal has been widely studied in recent years. Many methods have been used to remove it, but the final results are not very excellent. The total variation regularization method to solve the problem of the noise removal can preserve edge well, but sometimes produces undesirable staircasing effect. In this paper, we propose a variational model to remove multiplicative noise. An alternative algorithm is employed to solve variational model minimization problem. Experimental results show that the proposed model can not only effectively remove Gamma noise, but also Rayleigh noise, as well as the staircasing effect is significantly reduced. 展开更多
关键词 Noise REMOVAL STAIRCASE EFFECT RAYLEIGH Noise GAMMA Noise
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Asymptotically Necessary and Sufficient Quadratic Stability Conditions of T-S Fuzzy Systems Using Staircase Membership Function and Basic Inequality
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作者 Jianjian Zeng Lijuan Bao 《Open Journal of Applied Sciences》 CAS 2022年第11期1824-1836,共13页
Asymptotically necessary and sufficient quadratic stability conditions of Takagi-Sugeno (T-S) fuzzy systems are obtained by utilizing staircase membership functions and a basic inequality. The information of the membe... Asymptotically necessary and sufficient quadratic stability conditions of Takagi-Sugeno (T-S) fuzzy systems are obtained by utilizing staircase membership functions and a basic inequality. The information of the membership functions is incorporated in the stability analysis by approximating the original continuous membership functions with staircase membership functions. The stability of the T-S fuzzy systems was investigated based on a quadratic Lyapunov function. The asymptotically necessary and sufficient stability conditions in terms of linear matrix inequalities were derived using a basic inequality. A fuzzy controller was also designed based on the stability results. The derivation process of the stability results is straightforward and easy to understand. Case studies confirmed the validity of the obtained stability results. 展开更多
关键词 Takagi-Sugeno Fuzzy System Quadratic Stability Fuzzy Controller Staircase Membership Function
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Structural Join and Staircase Join Algorithms of Sibling Relationship 被引量:2
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作者 万常选 刘喜平 《Journal of Computer Science & Technology》 SCIE EI CSCD 2007年第2期171-181,共11页
The processing of XML queries can result in evaluation of various structural relationships. Efficient algorithms for evaluating ancestor-descendant and parent-child relationships have been proposed. Whereas the proble... The processing of XML queries can result in evaluation of various structural relationships. Efficient algorithms for evaluating ancestor-descendant and parent-child relationships have been proposed. Whereas the problems of evaluating preceding-sibling-following-sibling and preceding-following relationships are still open. In this paper, we studied the structural join and staircase join for sibling relationship. First, the idea of how to filter out and minimize unnecessary reads of elements using parent's structural information is introduced, which can be used to accelerate structural joins of parent-child and preceding-sibling-following-sibling relationships. Second, two efficient structural join algorithms of sibling relationship are proposed. These algorithms lead to optimal join performance: nodes that do not participate in the join can be judged beforehand and then skipped using B^+-tree index. Besides, each element list joined is scanned sequentially once at most. Furthermore, output of join results is sorted in document order. We also discussed the staircase join algorithm for sibling axes. Studies show that, staircase join for sibling axes is close to the structural join for sibling axes and shares the same characteristic of high efficiency. Our experimental results not only demonstrate the effectiveness of our optimizing techniques for sibling axes, but also validate the efficiency of our algorithms. As far as we know, this is the first work addressing this problem specially. 展开更多
关键词 XML query processing sibling relationship structural join staircase join
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A New Gradient Fidelity Term for Avoiding Staircasing Effect 被引量:1
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作者 董芳芳 刘震 《Journal of Computer Science & Technology》 SCIE EI CSCD 2009年第6期1162-1170,共9页
Image denoising with some second order nonlinear PDEs often leads to a staircasing effect, which may produce undesirable blocky image. In this paper, we present a new gradient fidelity term and couple it with these PD... Image denoising with some second order nonlinear PDEs often leads to a staircasing effect, which may produce undesirable blocky image. In this paper, we present a new gradient fidelity term and couple it with these PDEs to solve the problem. At first, we smooth the normal vector fields (i.e., the gradient fields) of the noisy image by total variation (TV) minimization and make the gradient of desirable image close to the smoothed normals, which is the idea of our gradient fidelity term. Then, we introduce the Euler-Lagrange equation of the gradient fidelity term into nonlinear diffusion PDEs for noise and staircasing removal. To speed up the computation of the vectorial TV minimization, the dual approach proposed by Bresson and Chan is employed. Some numerical experiments demonstrate that our gradient fidelity term can help to avoid the staircasing effect effectively, while preserving sharp discontinuities in images. 展开更多
关键词 image denoising staircasing effect gradient fidelity term normal vectors dual formulation
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REDUCING STAIRCASING ARTIFACTS IN SPECT RECONSTRUCTION BY AN INFIMAL CONVOLUTION REGULARIZATION 被引量:1
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作者 Zhifeng Wu Si Li +1 位作者 Xueying Zeng Andrzej Krol 《Journal of Computational Mathematics》 SCIE CSCD 2016年第6期626-647,共22页
The purpose of this paper is to investigate the ability of the infimal convolution regular- ization in curing the staircasing artifacts of the TV model in the SPECT reconstruction. We formulate the problem of SPECT re... The purpose of this paper is to investigate the ability of the infimal convolution regular- ization in curing the staircasing artifacts of the TV model in the SPECT reconstruction. We formulate the problem of SPECT reconstruction with the infimal convolution regu- larization as a convex three-block optimization problem and characterize its solution by a system of fixed-point equations in terms of the proximity operator of the functions involved in its objective function. We then develop a novel fixed-point proximity algorithm based on the fixed-point equations. Moreover, we introduce a preconditioning matrix motivated by the classical MLEM (maximum-likelihood expectation maximization) algorithm. We prove convergence of the proposed algorithm. The numerical results are included to show that the infimal convolution regularization is capable of effectively reducing the staircasing artifacts, while maintaining comparable image and coefficient recovery contrast. quality in terms of the signal-to-noise ratio 展开更多
关键词 SPECT Infimal Convolution Regularization Staircasing Artifacts Fixed-pointProximity Algorithm.
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