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Automatic Anterior Lamina Cribrosa Surface Depth Measurement Based on Active Contour and Energy Constraint

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Journal of Computer Science & Technology 2017年第6期32卷 1214-1221页

作者： Zai-Liang Chen peng peng Bei-ji Zou Hai-lan Shen Hao Wei Rong-Chang Zhao School of Information Science and Engineering Central South University Changsha 410083 China Center for Ophthalmic Imaging Research Central South University Changsha 410083 China 'Mobile Health' Ministry of Education-China Mobile Joint Laboratory Central South University Changsha 410083 China

The lamina cribrosa is affected by intraocular pressure, which is the major risk of glaucoma. However, the capability to evaluate the lamina cribrosa in vivo has been limited until recently due to poor image quality and the posterior laminar displacement of glaucomatous eyes. In this study, we propose an automatic method to measure the anterior lamina cribrosa surface depth （ALCSD）, including a method for detecting Bruch＇s membrane opening （BMO） based on k-means and region-based active contour. An anterior lamina cribrosa surface segmentation method based on energy constraint is also proposed. In BMO detection, we initialize the Chan-Vese active contour model by using the segmentation map of the k-means cluster. In the segmentation of anterior lamina cribrosa surface, we utilize the energy function in each A-scan to establish a set of candidates. The points in the set that fail to meet the constraints are removed. Finally, we use the B-spline fitting method to obtain the results. The proposed automatic method can model the posterior laminar displacement by measuring the ALCSD. This method achieves a mean error of 45.34 μm in BMO detection. The mean errors of the anterior lamina cribrosa surface are 94.1% within five pixels and 76.1% within three pixels.

关键词： anterior lamina cribrosa surface segmentation active contour energy constraint measurement

Analytical Solution of Thermocapillary Flow in Cylindrical Annuli with Curved Free Surface

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Journal of Thermal Science 2020年第1期29卷 260-267页

作者： LIU jia peng lan Key Laboratory of Low-Grade Energy Utilization Technologies and Systems of Ministry of Education College of Energy and Power Engineering Chongqing University

In this paper we consider thermocapillary flow with interface deformation in cylindrical annuli subjected to lateral temperature *** on the assumption that Reynolds,Marangoni and capillary numbers are very small,we expanded the governing equations in terms of a small parameter,and the zeroth-order one is the Stokes problem,which can be analytically solved by use of separation of variables *** are obtained for the zeroth-order fluid and thermal fields as well as the first-order interfacial ***,temperature distributions and interface shapes are presented and the influence of aspect ratios is investigated.

关键词： thermocapillary flow analytical solution interface deformation

外卖餐饮城市空间分布格局与商业特征耦合研究——以武汉市武昌区为例

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湖北大学学报（自然科学版） 2025年第1期47卷 34-42页

作者：兰心喆叶鹏湖北大学资源环境学院湖北武汉430062 区域开发与环境响应湖北省重点实验室(湖北大学) 湖北武汉430062

互联网外卖已经成为餐饮业不可忽视的售卖渠道,其空间分布与商业表现存在有别于传统线下餐饮的特征,本研究通过外卖POI数据与其市场数据,结合武汉市武昌区的土地分类数据,利用ArcGIS进行空间分析,对外卖餐饮的城市空间分布格局特征与商... 详细信息

互联网外卖已经成为餐饮业不可忽视的售卖渠道,其空间分布与商业表现存在有别于传统线下餐饮的特征,本研究通过外卖POI数据与其市场数据,结合武汉市武昌区的土地分类数据,利用ArcGIS进行空间分析,对外卖餐饮的城市空间分布格局特征与商业特征进行耦合研究。结果表明,外卖餐饮在空间分布上同时表现出了“均质化+多中心”的空间分布特征,且外卖店铺于不同功能区混杂之处表现出了更明显的聚集现象。

关键词：餐饮POI 外卖餐饮城市空间分布耦合分析

A new absolute nodal coordinate formulation beam element with multilayer circular cross section

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Acta Mechanica Sinica 2020年第1期36卷 82-96页

作者： peng lan Qinglong Tian Zuqing Yu School of Mechatronics Engineering Harbin Institute of TechnologyHarbin150001China

A systematic numerical integration method is applied to the absolute nodal coordinate formulation(ANCF)fully parameterized beam element with smooth varying and continuous cross ***,the formulation for the integration points and weight coefficients are given in the method which is used to model the multilayer beam with a circular cross *** negate the effect of the bending stiffness for the element used to model the high-voltage electrical wire,the general continuum mechanical approach is ***,the insulation cover for some particular types of the wire is described by the nearly incompressible Mooney-Rivlin material ***,a static problem is presented to prove the accuracy and convergence properties of the element,and a dynamic problem of a flexible pendulum is simulated whereby the balance of the energy can be *** experiment is carried out in which a wire is released as a pendulum and falls on a steel *** configurations of the wire are captured by a high-speed camera and compared with the simulation *** feasibility of the wire model can therefore be demonstrated.

关键词： Circular cross-section beam Absolute nodal coordinate formulation Electrical wire modeling Contact

BeXplorer:Visual analytics of dynamic interplay between communication and purchase behaviors in MMORPGs

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Visual Informatics 2019年第2期3卷 87-101页

作者： Junhua Lu Xiao Xie ji lan Tai-Quan peng Yingcai Wu Wei Chen State Key Lab of CAD&CG Zhejiang UniversityChina Department of Communication Michigan State UniversityUnited States

With the rapid development of massively multiplayer online role-playing games(MMORPGs),a huge amount of fine-grained data on the in-game activities of players have been recorded by MMORPGs *** data provide considerable opportunities with which to study the dynamic interplay between player behaviors and investigate the roles of various social structures that underlie such ***,it is challenging to model and visualize these behavioral *** study proposes a novel influence-susceptible model to measure the dynamic interplay between *** on this model,we introduce a new visual analytics system called *** system enables analysts to interactively explore the dynamic interplay between player purchase and communication behaviors and to examine the manner in which this interplay is bound by social structures where players are *** case studies and a task-based evaluation are conducted to demonstrate the effectiveness and applicability of our method.

关键词： Behavior visualization Game visualization MMORPG

TBHP-Mediated Oxidative Decarboxylative Cyclization in Water:Directand Sustainable Access to Anti-malarial Polycyclic Fused Quinazolinonesand Rutaecarpine

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Chinese Journal of Chemistry 2020年第11期38卷 1239-1244页

作者： Xingyu Chen Fei Xia Yifan Zhao ji Ma Yue Ma Dong Zhang lan Yang peng Sun Artemisinin Research Center and Institute of Chinese Materia Medica Academy of Chinese Medical SciencesBeijing 100700China

of main observation and conclusion Polycylic fused quinazolinones with anti-malarial activity were synthesized through tert-butyl hydro-peroxide(TBHP)-mediated oxidative decarboxylative cyclization between commercaly vailable isatins and cylic amines in one *** reaction pro-ceeds smoothly in water without additional ransition-metal catalyt,acid and *** newly synthesied products were evaluated to exhibit moderateto good anti-malaril activity against chloroquine drug-sensitive Plasmodium falciparum 3D7 *** this method aso provides direct approach to Rutaecarpine in good yield.

关键词： strain. smoothly oxidative

Spatial and temporal white noises under sublinear G-expectation

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Science China Mathematics 2020年第1期63卷 61-82页

作者： Xiaojun ji Shige peng School of Mathematics Shandong UniversityJinan 250100China Zhongtai Securities Institute for Financial Studies Shandong UniversityJinan 250100China

Under the framework of sublinear expectation,we introduce a new type of G-Gaussian random fields,which contains a type of spatial white noise as a special *** on this result,we also introduce a spatial-temporal G-white *** from the case of linear expectation,in which the probability measure needs to be known,under the uncertainty of probability measures,spatial white noises are intrinsically different from temporal cases.

关键词： sublinear expectation G-Brownian motion G-Gaussian random field G-white noise spatial and temporal white noise

Underestimation of the Warming Trend over the Tibetan Plateau during 1998–2013 by Global land Data Assimilation Systems and Atmospheric Reanalyses

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Journal of Meteorological Research 2020年第1期34卷 88-100页

作者： peng ji Xing YUAN Key Laboratory of Regional Climate–Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029 College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049 School of Hydrology and Water Resources Nanjing University of Information Science&TechnologyNanjing 210044

Accurate surface air temperature(T2m)data are key to investigating eco-hydrological responses to global *** of sparse in-situ observations,T2m datasets from atmospheric reanalysis or multi-source observation-based land data assimilation system(LDAS)are widely used in research over alpine regions such as the Tibetan Plateau(TP).It has been found that the warming rate of T2m over the TP accelerates during the global warming slowdown period of 1998–2013,which raises the question of whether the reanalysis or LDAS datasets can capture the warming *** evaluating two global LDASs,five global atmospheric reanalysis datasets,and a high-resolution dynamical downscaling simulation driven by one of the global reanalysis,we demonstrate that the LDASs and reanalysis datasets underestimate the warming trend over the TP by 27%–86%during 1998–*** is mainly caused by the underestimations of the increasing trends of surface downward radiation and nighttime total cloud amount over the southern and northern TP,*** GLDAS2.0,ERA5,and MERRA2 reduce biases of T2m simulation from their previous versions by 12%–94%,they do not show significant improvements in capturing the warming *** WRF dynamical downscaling dataset driven by ERA-Interim shows a great improvement,as it corrects the cooling trend in ERA-Interim to an observation-like warming trend over the southern *** results indicate that more efforts are needed to reasonably simulate the warming features over the TP during the global warming slowdown period,and the WRF dynamical downscaling dataset provides more accurate T2m estimations than its driven global reanalysis dataset ERA-Interim for producing LDAS products over the TP.

关键词： land data assimilation system(LDAS) reanalysis datasets WRF dynamical downscaling Tibetan Plateau global warming slowdown

Hugl-1 induces apoptosis in esophageal carcinoma cells both in vitro and in vivo

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World Journal of Gastroenterology 2013年第26期19卷 4127-4136页

作者： jia Song Xiu-lan peng Meng-Yao ji Ming-Hua Ai ji-Xiang Zhang Wei-Guo Dong Department of Gastroenterology Renmin Hospital of Wuhan University Department of Gastroenterology Renmin Hospital of Wuhan University

AIM: To determine whether the human giant larvae homolog 1 gene (Hugl-1/Llg1/Lgl1) exerts tumor suppressor effects in esophageal cancer. METHODS: We constructed a Hugl-1 expression plasmid, pEZ-M29-Hugl1, for gene transfection. We transfected the pEZ-M29-Hugl1 plasmid into Eca109 esophageal cancer cell lines with Lipofectamine 2000 to overexpress Hugl-1. Real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were performed to determine the effects of the plasmid on Hugl-1 expression. In vitro cell proliferation and apoptosis were examined separately by cell counting Kit-8 (CCK-8) assay, flow cytometry, and Western blotting before and after the transfection of the plasmid into Eca109 cells. Cell cycle distribution was assessed with flow cytometry. The effect of Hugl-1 overexpressing on tumor growth in vivo was performed with a xenograft tumor model in nude mice. Expression of Hugl-1 in xenograft tumor was analyzed by *** transferase-mediated dUTP nick end-labeling (TUNEL) technique was performed to detect and quantitate apoptotic cell. RESULTS: The transfection efficiency was confirmed with real-time RT-PCR and Western blotting. Our results show that compared with control groups the mRNA levels and protein levels of Hugl-1 in pEZ-M29-Hugl1-treated group were remarkably increased (P < 0.05). The CCK-8 assay demonstrated that the growth of cells overexpressing Hugl-1 was significantly lower than control cells. Cell cycle distribution showed there was a G 0 /G 1 cell cycle arrest in cells overexpressing Hugl-1 (64.09% ± 3.14% vs 50.32% ± 4.60%, 64.09% ± 3.14% vs 49.13% ± 2.24%). Annexin V-fluorescein isothiocyanate revealed that apoptosis was significantly increased in cells overexpressing Hugl-1 compared with control group (17.33% ± 4.76% vs 6.90% ± 1.61%, 17.33% ± 4.76% vs 6.27% ± 0.38%). Moreover, we found that Hugl-1 changes the level of the anti-apoptotic protein Bcl-2 and the proapoptotic protein Bax and the ac

关键词： Esophageal squamous cell carcinoma Human giant larvae homolog 1 Proliferation Apoptosis