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Generating Circulation Designs Using Shape Grammars

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Tsinghua Science and Technology 2018年第6期23卷 680-689页

作者： Chao Li Lei Jiang Fanrui Sun kang zhang School of Computer Software Tianjin University

Shape grammars are well-known tools to explore abstract systems of shapes and their relationships. Although there has been much research on the use of shape grammars in the field of architectural styles, there has been little investigation into the concept of circulation using shape grammars. Circulation is a tool used in architecture and interior design and is formed by connecting the points left by the movement of human beings through indoor or outdoor spaces. This study shows that shape grammars are also helpful in this particular field by presenting how a parametric shape grammar is applied to generate circulation designs, and the system automatically generates four basic types of complex circulations. According to the specific conditions and requirements of each commercial space, different forms of circulation can be specified and generated.

关键词： circulation shape grammar Palladian grammar shape grammar interpreter

Experiment and Numerical Simulation of Free Water Jet by a Central-body Nozzle

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Chinese Journal of Mechanical Engineering 2010年第6期23卷 797-804页

作者： YANG Minguan zhang Feng kang Can GAO Bo School of Energy and Power Engineering Jiangsu University Zhenjiang 212013 China

The recent research about cavitation jet mainly focuses on the organ-pipe nozzle and triangular nozzle. The research content mainly includes the optimized design about the structure of nozzles, the observation and flow analysis about the cavitation jet in the water, and the theory of rock attacked by the cavitation jet, while the energy characteristic of the free jet is not studied yet. In China, the research about the central-body nozzle is almost empty. For the purpose of studying the energy characteristic and the structure of free water jet discharged from central-body nozzle, an experiment with phase Doppler particle anemometry（PDPA） technology is carried out to measure the free water jet flow, which is produced by a central-body nozzle under the jet pressure of 15 MPa. While five sections with different axial distances from the nozzle outlet are selected for data process and analysis, the axial and radial velocity and the droplets of the particle size are studied. Meanwhile, numerical calculation of corresponding flow field is conducted by using volume of fluid（VOF） multiphase model, and the jet flow feature is discussed. The experimental and calculating results show that the axial velocity of high speed jet flow dissipates slowly in the air, and the core area and diffused area are discovered. The diameter of droplet in the core area is small, and jet energy is concentrated, while in the diffusion area, water is mingled with ambient air and radial velocity is relatively large. Obvious low-pressure area exists behind the central body and potential cavitation may occur in that area. The proposed research reveals the energy characteristic of free jet discharged from central-body nozzle, provides the theoretical basis for preestimating erosion feature of the central-body nozzle and also the theoretical foundation for revealing the mechanism of erosion.

关键词： central-body nozzle free water jet phase Doppler particle anemometry(PDPA) energy characteristic VOF model

Microstructure studies of the grinding damage in monocrystalline silicon wafers

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Rare Metals 2007年第1期26卷 13-18页

作者： zhang Yinxia kang Renke GUO Dongming JIN Zhuji Key Laboratory for Precision and Non-traditional Machining Technology of Chinese MinisWy of Education Dalian University of Technology Dalian116024 China

The depth and nature of the subsurface damage in a silicon wafer will limit the performance of IC components. Damage microstructures of the silicon wafers ground by the #325, #600, and #2000 grinding wheels was analyzed. The results show that many microcracks, fractures, and dislocation rosettes appear in the surface and subsurface of the wafer ground by the #325 grinding wheel. No obvious microstructure change exists. The amorphous layer with a thickness of about 100 nm, microcracks, high density dislocations, and polycrystalline silicon are observed in the subsurface of the wafer ground by the #600 grinding wheel. For the wafer ground by the #2000 grinding wheel, an amorphous layer of about 30 nm thickness, a polycrystalline silicon layer, a few dislocations, and an elastic deformation layer exist. In general, with the decrease in grit size, the material removal mode changes from micro-fracture mode to ductile mode gradually.

关键词： silicon wafers grinding subsurface damage microstructure

Research on blade tip clearance cavitation and turbulent kinetic energy characteristics of axial flow pump based on the partially-averaged Navier-Stokes model

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Journal of Hydrodynamics 2024年第1期36卷 184-201页

作者： Xiao-qi Jia Shuai-kang zhang Zu-chao Zhu Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou310018China

To reveal the cavitation forms of tip leakage vortex(TLV)of the axial flow pump and the flow mechanism of the flow field,this research adopts the partially-averaged Navier-Stokes(PANS)model to simulate the cavitation values of an axial flow pump,followed by experimental *** experimental result shows that compared with the shear stress transport(SST)k-ωmodel,the PANS model significantly reduces the eddy viscosity of the flow field to make the vortex structure clearer and allow the turbulence scale to be more robustly *** cavitation area within the axial flow pump mainly comprises of TLV cavitation,clearance cavitation and tip leakage flows combined effect of triangular cloud cavitation *** formation and development of cavitation are accompanied by the formation and evolution of vortex,and variations in vortex structure also generate and promote the development of *** addition,an in-depth analysis of the relationship between the turbulent kinetic energy(TKE)transport equation and cavitation patterns was also conducted,finding that the regions with relatively high TKE are mainly distributed around gas/liquid boundaries with serious cavitation and evident gas-liquid *** phenomenon is mainly attributed to the combined effect of the pressure action term,stress diffusion term and TKE production term.

关键词： Cavitation axial flow pump tip leakage vortex(TLV) partially-averaged Navier-Stokes(PANS)model turbulent kinetic energy(TKE)

Principle of equivalency of bed structures and bed load motion

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International Journal of Sediment Research 2012年第3期27卷 288-305页

作者： Zhao-yin WANG kang zhang State Key Lab of Hydroscience and Engineering Tsinghua University

Step-pool systems and cobble clusters are structures composed of boulders and cobbles on mountain streambeds rearranged by flood flow to reach high resistance and high bed *** bed structures and bed load motion can protect the riverbed from *** each step-pool,the flow energy is transformed into turbulence,and finally into *** load motion also consumes flow energy and plays a role to protect the bed from *** collision of bed load particles with the bed results in a force,known as dispersive force,which balances the lift force and controls the erosion of bed *** investigations and field experiments were conducted in the Xiaojiang River basin on the Yunnan-Guizhou plateau of China,where there were incised streams and stable streams with bed load motion or with step-pool *** study reveals that for a given stream power, strong bed structures are associated with low or zero bed load transportation;and weak or no bed structures are associated with intensive bed load *** showed that for incised streams, the final bed profiles were the same if there was bed load motion or there were bed *** key stones that made up the bed structures,for instance the large boulders in steps,were removed,the flow immediately scoured the sediment *** bed load transportation sharply increased by 100 times and the median diameter of bed load increased by 2-20 *** structures and bed load motion are mutually replaceable for their effects on flow energy consumption and streambed incision *** is the principle of equivalency of bed load motion and bed *** is due to the principle that there was no bed load motion in the Yalutsangpo Grand Canyon,where a very strong step-pool system had developed,although the bed gradient and shear stress of flow were extremely high.A possible application of this principle for incision control of the downstream reaches of the Three Gorges Dam is also discussed in t

关键词： Bed structures Bed load motion Riverbed incision Stream power Step-pool system

Visual order of Chinese ink paintings

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Visual Computing for Industry,Biomedicine,and Art 2020年第1期3卷 257-265页

作者： Zhen-Bao Fan kang zhang Department of Computer Science The University of Texas at DallasRichardsonTX 75082-3021USA

Visual order is one of the key factors influencing the aesthetic judgment of *** paper reports the results of evaluating the influence of extracted features on visual order in Chinese ink paintings,using a regression *** use nine contemporary artists’paintings as examples and extract features related to the visual order of their paintings.A questionnaire survey is conducted to collect people’s rating scores on the visual *** regression modeling,our research analyzes the significance of each feature and validates the influences of the features on the visual order.

关键词： Aesthetic measurement Paintings Visual order Visual information processing

A new insight for stem cell therapy:apoptotic stem cells as a key player

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Signal Transduction and Targeted Therapy 2022年第9期7卷 3181-3183页

作者： Yuhe Huang Ziyi Bai kang zhang Laboratory of Aging Research and Cancer Drug Target State Key Laboratory of BiotherapyNational Clinical Research Center for GeriatricsWest China HospitalSichuan UniversityNo.17Block 3Southern Renmin RoadChengduSichuan 610041PR China Zhuhai International Eye Center Zhuhai People's Hospital and The First Afliated Hospital of Faculty of MedicineMacao University of Science and TechnologyZhuhaiChina

Recently,two studies on therapeutic effects of stem cell therapy were published in Signal Transduction and Target Therapy1 and Nature Communications.2These studies have shed the light on a unique aspect of stem cell therapy which involves a previously unrecognized key player,namely apoptotic *** two publications have elucidated how the apoptotic cells exert immunomodulatory effects in stem cell therapy in several animal models.

关键词： apo therapy Therapy

EXPERIMENTAL RESEARCH ON RADIATION FROM DOUBLE CYLINDRICAL STRUCTURES

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Journal of Hydrodynamics 2006年第2期18卷 156-160页

作者： JI Gang zhang Wei-kang ZHOU Qi-dou Department of Naval Architecture and Ocean Engineering Naval University of Engineering Wuhan 430033China

An experiment on radiation from double cylindrical structures was held in an open-air pond. Radiation responses from one-point harmonic force driven model and two-point stochastic forces driven model were measured. Nu... 详细信息

关键词： acoustic radiation experiment double cylindrical structure

q-Deformations of 3-Lie Algebras

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Algebra Colloquium 2017年第3期24卷 519-540页

作者： Ruipu Bai Lixin Lin Yan zhang Chuangchuang kang College of Mathematics and Information Science Hebei University Baoding Hebei 071002 China

q-Deformations of 3-Lie algebras and representations of q-3-Lie algebras are discussed. A q-3-Lie algebra （A, [, ,]q, [, ,]＇q, Ja）, where q ∈ F and q ≠ 0, is a vector space A over a field F with 3-cry linear multiplications [,, ]q and [,, ]＇q from A 3 to A, and a map Jq ： A 5→ F satisfying the q-Jacobi identity Jq（x1, x2, x3, x4, x5）[x1, x2, [x3, x4, x5]q]＇q = Jq（x4, x5, x1, x2, x3）[x4, x5, [x1, x2, x3]q]＇q for all x1 ∈ A. If the multiplications satisfy that [,,]q = [,,]＇q and [,,]q is skew-symmetry, then （A, [,,]q, Jq） is called a type （I）-q-3- Lie algebra. From q-Lie algebras, group algebras and commutative associative algebras, q-3-Lie algebras and type （I）-q-3-Lie algebras are constructed. Also, the non-trivial one- dimensional central extension of q-3-Lie algebras is investigated, and new q-3-Lie algebras （DerqC[x,x-1], [, ,]q, [, ,]＇q, Jq）, and （Derδq C[x,x-1], [, ,]q, [,,]＇q, Jq） are obtained.

关键词： q-3-Lie algebra q-deformation q-Jacobi identity