检索结果-南通市图书馆

Compactness in fuzzy logic

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1998年第14期43卷 1166-1171页

作者： YING Mingsheng department of Computer Science and Technology, tsinghua university, beijing 1.0084, china department of Computer Science and Technology Tsinghua University Beijing China

Compactness in Pavelka’s fuzzy logic for some compact lattices of truth values is shown, and the concept of gradual compactness is introduced to establish some corresponding results in a more general setting.

关键词： fuzzy logic compactness gradual compactness.

A new DSmT combination rule in open frame of discernment and its application

在线全文

学校读者我要写书评

暂无评论

Science china(Information Sciences) 2012年第3期55卷 551-557页

作者： WEN ChengLin1, XU XiaoBin1,2 , JIANG HaiNa1 & ZHOU Zhe1 1School of automation, Hangzhou DianZi university, Hangzhou 310018, china 2department of automation and tsinghua National Laboratory for Information Science and Technology, tsinghua university, beijing 100049, china 1. School of automation Hangzhou DianZi University Hangzhou 310018 China2. Department of Automation and Tsinghua National Laboratory for Information Science and Technology Tsinghua University Beijing 100049 China

A new combination rule based on Dezert-Smarandache theory (DSmT) is proposed to deal with the conflict evidence resulting from the non-exhaustivity of the discernment frame. A two-dimensional measure factor in Dempster-Shafer theory (DST) is extended to DSmT to judge the conflict degree between evidence. The original DSmT combination rule or new DSmT combination rule can be selected for fusion according to this degree. Finally, some examples in simultaneous fault diagnosis of motor rotor are given to illustrate the effectiveness of the proposed combination rule.

关键词： DSmT rule of combination open frame of discernment evidence conflict simultaneous faults diagnosis generalized basic probability assignment

An atlas-based fuzzy connectedness method for automatic tissue classification in brain MRI

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2006年第10期16卷 1106-1110页

作者： ZHOU Yongxin and BAI Jing (department of Biomedical Engineering, tsinghua university, beijing 1.0084, china) [a]department of Biomedical Engineering Tsinghua University Beijing China

A framework incorporating a subject-registered atlas into the fuzzy connectedness (FC) method is proposed for the automatic tissue classification of 3D images of brain MRI. The pre-labeled atlas is first registered onto the subject to provide an initial approximate segmentation. The initial segmentation is used to estimate the intensity histograms of gray matter and white matter. Based on the estimated intensity histograms, multiple seed voxels are assigned to each tissue automatically. The normalized intensity histograms are utilized in the FC method as the intensity probability density function (PDF) directly. Relative fuzzy connectedness technique is adopted in the final classification of gray matter and white matter. Experimental results based on the 20 data sets from IBSR are included, as well as comparisons of the performance of our method with that of other published methods. This method is fully automatic and operator-independent. Therefore, it is expected to find wide applications, such as 3D visualization, radiation therapy planning, and medical database construction.

关键词： fuzzy connectedness atlas-based segmentation brain tissue classification MR1.

Particle tunnels across the horizon of Garfinkle-Horowitz-Strominger dilaton black hole

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 601-610页

作者： FANG HengZhong1 & ZHAO Zheng2 1 department of Physics, china university of Petroleum, Dongying 257061, china 2.department of Physics, beijing Normal university, beijing 100875, china department of Physics China University of Petroleum Dongying 257061 China department of Physics Beijing Normal University Beijing 100875 China

We promote the work of Parikh and Wilczek on the black hole radiation to the emission of massive and charged particles from Garfinkle-Horowitz-Strominger black hole. The energy and charge of the space-time are conservational during the course of the evaporation. The calculation shows that the emission spectrum is not precisely thermal, while has a correction, and the conclusion supports the view- point of information conservation.

关键词： Hawking radiation, black body spectrum, barrier, information loss, entropy of black hole, Komar energy

Study on Numerical Simulation of Mold Filling and Heat Transfer in Die Casting Process

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2000年第3期16卷 269-272页

作者： Liangrong JIA, Shoumei XIONG and Baicheng LIU (department of Mechanical Engineering, tsinghua university, beijing 1.0084, china) department of Mechanical Engineering Tsinghua University Beijing 100084 China

A 3-D mathematical model considering turbulence phenomena has been established based on a computational fluid dynamics technique, so called 3-D SOLA-VOF (Solution Algorithm-Volume of Fluid), to simulate the fluid flow of mold filling process of die casting. In addition, the mathematical model for simulating the heat transfer in die casting process has also been established. The computation program has been developed by the authors with the finite difference method (FDM) recently. As verification, the mold filling process of a S-shaped die casting has been simulated and the simulation results coincide with that of the benchmark test. Finally, as a practical application, the gating design of a motorcycle component was modified by the mold filling simulation and the dies design of another motorcycle component was optimized by the heat transfer simulation. All the optimized designs were verified by the production practice.

关键词： Study on Numerical Simulation of Mold Filling and Heat Transfer in Die Casting Process Mold Simulation

LARGE DEFLECTION THEORY OF NANOBEAMS

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2010年第5期23卷 394-399页

作者： Dujuan Zeng Quanshui Zheng 1(department of Engineering Mechanics,tsinghua university,beijing 1.0084,china) [a] department of Engineering Mechanics Tsinghua University Beijing 100084 China

One-dimensional nanostructured materials are often used as beams in many applications such as ultrahigh-frequency resonators and ultrasensitive sensors. Compared with usual macroscopic beams, nanobeams have much higher surface/volume ratios so that their surface energies may play a significant role. Besides, they often bear large deflections due to their typically large slenderness ratios and larger elastic ranges. There is, however, lack of a theory that takes into account of both the above two features owned by nanobeams. In this paper, we present such a theory and give applied examples to show that surface energy and large deflection may individually or jointly have notable effects.

关键词： nanobeam surface energy large deflection

New evidence for lack of CMB power on large scales

在线全文

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 567-570页

作者： LIU Hao1 & LI TiPei1,2,3 1 Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, beijing 100049, china 2.department of Physics & Center for Astrophysics, tsinghua university, beijing 1.0084, china 3 department of Engineering Physics & Center for Astrophysics, tsinghua university, beijing 1.0084, china 1. Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China2. Department of Physics & Center for Astrophysics Tsinghua University Beijing 100084 China3. Department of Engineering Physics & Center for Astrophysics Tsinghua University Beijing 100084 China

A digitalized temperature map is recovered from the first light sky survey image published by the Planck team, from which an angular power spectrum of the cosmic microwave background (CMB) is derived. The amplitudes of the low multipoles (low-l) measured from the preliminary Planck power spectrum are significantly lower than those reported by the WMAP team. Possible systematical effects are far from enough to explain the observed low-l differences.

关键词： cosmology cosmic microwave background data analysis

SUPERSATURATED DESIGN WITH MORE THAN TWO LEVELS

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of Mathematics,Series B 2001年第2期22卷 183-194页

作者： LU XUAN SUN YIZHOU department of Mathematical Science, tsinghua university, beijing 1.0084, china. department of Mathematical Science Tsinghua Univeristy Beijing 100084 China

Supersaturated designs are useful in screening experiments. This paper discusses the topic of multi-level supersaturated design. Two quantities, E(d2) and Df, are proposed to evaluate the optimality of supersaturated designs. A lower bound of E(d2) is obtained with a necessary condition for achieving it. Some E(d2)-optimal supersaturated designs of 3, 4, and 5 levels are given.

关键词： D-efficiency Screening experiment Fractional factorial design Orthogonality

NUMERICAL DISSIPATION FOR THREE-POINT DIFFERENCE SCHEMES TO HYPERBOLIC EQUATIONS WITH UNEVEN MESHES

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2003年第4期21卷 519-534页

作者： Zi-niu Wu(department of Engineering Mechanics, tsinghua university, beijing 1.0084, china) department of Engineering Mechanics Tsinghua University Beijing 100084 China

The widely used locally adaptive Cartesian grid methods involve a series of abruptly refined interfaces. The numerical dissipation due to these interfaces is studied here for three-point difference approximations of a hyperbolic equation. It will be shown that if the wave moves in the fine-to-coarse direction then the dissipation is positive (stabilizing), and if the wave moves in the coarse-to-fine direction then the dissipation is negative (destabilizing).

关键词： Refined interfaces Numerical dissipation Three-point difference approxima-tion Hyperbolic equation.