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Microgravity may help future organ/tissue manufacture

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Science China(Life Sciences) 2016年第8期59卷 850-853页

作者： jin han Jianwu Dai State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101China

Stem cells are a group of multipotent or pluripotent cells which could differentiate into specialized cells or could self-renew to duplicate themselves. During the body devel- oping period, stem cells differentiated into specialized cells to build the whole body. In the adult organisms, stem cells live in seclusion and are ready to repair the injuries of tis- sues. Within one tissue, stem cells could differentiate in to all types of somatic cells of the tissue, for example,

关键词： manufacture specialized pluripotent differentiate duplicate renew repair themselves ready injuries

Investigation on the influence of vortex generator on particle resuspension

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Particuology 2024年第3期86卷 126-136页

作者： Dongchi Yu Jun-Li Lin jin-han Xie ASML 80W Tasman DrSan Jose95134CaliforniaUSA Department of Mechanics and Engineering Science at College of Engineering and State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing100081China

The vortex generator(VG)and its well-known effect in flow optimization are widely studied and employed across different engineering ***,while the same working principles of VG may be well suited for the applications on surface-cleaning technologies,such promising potential is hardly,if any,explored in the published ***,in the present study,the influence on flow-induced particle resuspension brought by a rectangular vG in a channel flow is investigated with the help of highfidelity computational fluid dynamics *** increases of particle removal forces and resuspension rates are discovered in long,strip-like regions with reduced boundary-layer thickness resulted from the vG-induced vortices,and the enhancement effect is especially significant for configurations with the VG installed at a greater angle of *** is also shown that while the resuspension enhancements on the lower and the upper surfaces of the channel exhibit distinct statistical characteristics,having a VG in the channel improves the overall particle-removing capability of the channel flow by introducing higher surface-averaged removal forces and particle resuspension *** but not least,the increase of resuspension rate is especially significant for the smaller,micron-scale particles which are otherwise hardly disturbed by a VG-less channel flow,and such resuspension-enhancement effectgenerally subsides with increasing particle size.

关键词： Particle resuspension Vortexgenerator CFD Surface cleaning

Improved CICA Algorithm Used for Single Channel Compound Fault Diagnosis of Rolling Bearings

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Chinese Journal of Mechanical Engineering 2016年第1期29卷 204-211页

作者： CHEN Guohua QIE Longfei ZhanG Aijun han jin College of Mechanical and Electrical Engineering Beijing University of Chemical Technology School of Mechanical Engineering Beijing Institute of Technology

A Compound fault signal usually contains multiple characteristic signals and strong confusion noise, which makes it difficult to separate week fault signals from them through conventional ways, such as FFT-based envelope detection, wavelet transform or empirical mode decomposition individually. In order to realize single channel compound fault diagnosis of bearings and improve the diagnosis accuracy, an improved CICA algorithm named constrained independent component analysis based on the energy method （E-CICA） is proposed. With the approach, the single channel vibration signal is firstly decomposed into several wavelet coefficients by discrete wavelet transform（DWT） method for the purpose of obtaining multichannel signals. Then the envelope signals of the reconstructed wavelet coefficients are selected as the input of E-CICA algorithm, which fulfills the requirements that the number of sensors is greater than or equal to that of the source signals and makes it more suitable to be processed by CICA strategy. The frequency energy ratio（ER） of each wavelet reconstructed signal to the total energy of the given synchronous signal is calculated, and then the synchronous signal with maximum ER value is set as the reference signal accordingly. By this way, the reference signal contains a priori knowledge of fault source signal and the influence on fault signal extraction accuracy which is caused by the initial phase angle and the duty ratio of the reference signal in the traditional CICA algorithm is avoided. Experimental results show that E-CICA algorithm can effectively separate out the outer-race defect and the rollers defect from the single channel compound fault and fulfill the needs of compound fault diagnosis of rolling bearings, and the running time is 0.12% of that of the traditional CICA algorithm and the extraction accuracy is 1.4 times of that of CICA as well. The proposed research provides a new method to separate single channel compound fault signals.

关键词： compound fault diagnosis, energy method constrained independent component analysis(CICA) diserete wavelet transform(DWT)

A Method for Assessing the Fairness of Health Resource Allocation Based on Geographical Grid

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Computers, Materials & Continua 2020年第8期64卷 1171-1184页

作者： jin han Wenhao Jiang jin Shi Sun Xin jin Peng Haibo Liu School of Computer&Software Nanjing University of Information Science&TechnologyNanjing210044China School of Information Management Nanjing UniversityNanjing210036China Department of Computer Science Aberystwyth UniversityAberystwythSY233DBUK

The assessment of the fairness of health resource allocation is an important part of the study for the fairness of social *** data used in most of the existing assessment methods comes from statistical yearbooks or field survey *** statistics are generally based on administrative areas and are difficult to support a fine-grained evaluation *** response to these problems,the evaluation method proposed in this paper is based on the query statistics of the geographic grid of the target area,which are more accurate and *** on the query statistics of hot words in the geographic grids,this paper adopts the maximum likelihood estimation method to estimate the population in the grid ***,according to the statistical yearbook data of Hunan province,the estimated number and actual number of hospitals in each grid are analyzed and compared to measure the fairness of health resource allocation in the target *** show that the geographical grid population assessment based on hot words is more accurate and close to the actual *** estimated average error is only about 17.8 *** method can assess the fairness of health resource allocation in any scale,and is innovative in data acquisition and evaluation methods.

关键词： Health resource allocation fairness assessment geographical grid hot words

A study of the evolution of nanoparticle dynamics in a homogeneous isotropic turbulence flow via a DNS-TEMOM method

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Journal of Hydrodynamics 2020年第6期32卷 1091-1099页

作者： Hong-ye Ma Ming-zhou Yu han-hui jin College of Mechanical and Electrical Engineering China Jiliang UniversityHangzhou310018China Institute of Fluid Engineering Zhejiang UniversityHangzhou310027China

In this article,a coupling of the direct numerical simulation(DNS)and the population balance modeling(PBM)is implemented to study the effect of turbulence on nanoparticle dynamics in homogenous isotropic turbulence(HIT).The DNS is implemented based on a pseudo-spectral method and the PBM is implemented using the Taylor-series expansion method of *** result verifies that coagulation due to turbulent shear force has a bigger impact on the evolution of number concentration,polydispersity,and average diameter of nanoparticles than Brownian coagulation in the *** Reynolds number plays an important role in determining the number concentration,polydispersity,and average diameter of nanoparticles,and these quantities change more rapidly with an increase of Reynolds *** is also found that the initial geometric standard deviation slows down the evolution of particle dynamics,but almost has no influence on the polydispersity of nanoparticles.

关键词： nanoparticle dynamics Turbulence pseudo-spectral method Taylor-series expansion method of moments

Synchronous renal pelvis carcinoma associated with small lymphocytic lymphoma:A case report

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World Journal of Clinical Cases 2022年第29期10卷 10663-10669页

作者： han-jin Yang Xiao Huang Department of Pathology The First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310003Zhejiang ProvinceChina Department of Urology The First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhou 310003Zhejiang ProvinceChina

BACKGROUND Chronic lymphocytic leukemia/small lymphocytic lymphoma(CLL/SLL) is often associated with an increased risk of developing subsequent neoplasms of epithelial and mesenchymal *** of CLL/SLL and urothelial carcinoma(UC) is very ***,we report a case of synchronous renal pelvis carcinoma with *** SUMMARY A 78-year-old man presented with the complaint of terminal painless gross hematuria for the past 2 *** physical examination,enlarged lymph nodes were palpable in the cervical and axillary *** patient’s peripheral blood film was *** had a significant smoking history for the past 50 *** revealed bleeding in the left upper urinary *** computed tomography imaging demonstrated a left renal pelvis *** patient underwent laparoscopic radical *** revealed left renal pelvis high-grade invasive papillary UC and SLL involving the kidney and bone *** pelvis lymphatic tissue and lymphocytes were positive for CD5,CD20,and *** addition,the following results were obtained:CD3(-),Ki-67(30%+),Bcl-2(+),Bcl-6(+),CD10(-),and CD79a(+).Moreover,no UC metastasis was observed in the lymph *** This is the first case of coincident CLL/SLL and upper tract UC in the *** patients with lymphadenopathies should always be investigated to rule out the possibility of synchronous or metachronous malignancy.

关键词： Synchronous malignancy Coincidence Upper tract urothelial carcinomas Small lymphocytic lymphoma

Inverse Curvature Flows of Rotation Hypersurfaces

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Acta Mathematica Sinica,English Series 2021年第11期37卷 1692-1708页

作者： Yu han jin Xian Feng WANG Yong WEI School of Mathematical Sciences and LPMC Nankai UniversityTianjin 300071P.R.China School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026P.R.China

We consider the inverse curvature flows of smooth,closed and strictly convex rotation hypersurfaces in space forms M_(κ)^(n+1)with speed function given by F^(-α),whereα∈(0,1]forκ=0,-1,α=1 forκ=1 and F is a smooth,symmetric,strictly increasing and 1-homogeneous function of the principal curvatures of the evolving *** show that the curvature pinching ratio of the evolving hypersurface is controlled by its initial value,and prove the long time existence and convergence of the *** second derivatives conditions are required on F.

关键词： Inverse curvature flow rotation hypersurface

Numerical Investigation on Wet Steam Non-equilibrium Condensation Flow in Turbine Cascade

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Journal of Thermal Science 2012年第6期21卷 525-532页

作者： JU Feng-ming YAN Pei-gang han Wan-jin School of Energy Science & Engineering Harbin Institute of Technology Harbin 150001 China

Based on the two-phase wet steam flow with spontaneous condensation, experimental verification and flow analysis on nozzle and 2D cascade are carried out. The 3D Reynolds-Averaged gas-liquid two-phase flow control equation solver is explored with k-e-kp turbulence model. Furthermore, 3D flow numerical simulation on the last stage stator of the steam turbine is carried out. The results show that a sudden pressure rise on blade suction surface is mainly caused by the droplet growth in condensation flow. The more backward the condensation position is in cascade passage, the less the sudden pressure rise from condensation is, and the larger the nucleation rate is, the maximum under-cooling and the number of droplets per unit volume are. Interaction of condensation wave and shock wave has imposed greater influence on the parameters of the blade cascade outlet.

关键词： turbine cascade wet steam non-equilibrium condensation two-phase flow

Physical Background of the Unified Scaling Law in Spiral Galaxies

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Chinese Physics Letters 2000年第12期17卷 935-936页

作者： ZOU Zhen-Long han jin-Lin Beijing Astronomical Observatory and Beijing Astrophysical Center National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012

We discussed the physical background of the unified scaling law in spiral galaxies,and qualitatively obtained the power index of the empirical relation among the luminosity L,radius R and the rotation velocity *** also discussed the possible causes for the data dispersion on the plane in three-dimensional space of these parameters.

关键词： parameters galaxies rotation