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Experiment and simulation research of storage for small grain steel silo

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International Journal of Agricultural and Biological Engineering 2016年第3期9卷 170-178页

作者： Zhang Ledao Chen xi Liu Hang Peng Wei Zhang Zhongjie Ren Guangyue College of Food and Biology Engineering Henan University of Science and TechnologyLuoyang 4710123China Academy of State Administration of Grain Beijing 100038China

Knowing the temperature distribution in silo is a convenient and efficient way to control the process of grain storage.A three-dimensional(3-D)numerical model was used to study the temperature variation in small grain steel silo under quasi-steady *** this study,experiments were conducted and porous media model was *** of numerical simulation and experiment were compared and the results indicated that grain temperature was influenced by temperature of the wall,grain stacking height,and the distance between grain and *** higher the wall temperature,the more the temperature *** the wall temperature is low,the effect of wall temperature on temperature distribution is *** temperature at the top part of grain varied obviously with the changes of temperature in air ***,numerical simulation results coincided with experimental results and the model established in this study is valuable for predicting grain temperature in steel silo.

关键词： small grain steel silo quasi-steady state storage numerical simulation porous media model grain storage

半开放式的多配送中心纯电动车辆路径优化问题

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交通运输系统工程与信息 2019年第6期19卷 199-205页

作者：马冰山胡大伟陈希琼胡卉长安大学汽车学院

电子商务促使越来越多的物流企业采用多配送中心模式优化车辆的配送路径,纯电动汽车逐渐替代了传统的燃油配送车辆,以改善生态环境.结合多配送中心联合服务模式的特点和纯电动物流车辆的行驶特征,构建带时间窗的半开放式多配送中心纯电... 详细信息

电子商务促使越来越多的物流企业采用多配送中心模式优化车辆的配送路径,纯电动汽车逐渐替代了传统的燃油配送车辆,以改善生态环境.结合多配送中心联合服务模式的特点和纯电动物流车辆的行驶特征,构建带时间窗的半开放式多配送中心纯电动车辆路径优化模型,设计蚁群算法对其求解.算例对比分析结果表明:半开放式的多配送中心联合服务,能合理利用相关物流资源,改善车辆路径,降低物流费用,但需要寻找合适数量和位置的配送中心进行联合,才能达到节约成本的最佳效果;相比单配送中心,多配送中心联合服务提供了更多潜在的较低价格的充电点,在配送中心补充电量可在一定程度上节约物流成本.

关键词：物流工程半开放式车辆路径蚁群算法纯电动车辆多配送中心联合服务

Novel genetic variations of the p53R2 gene in patients with colorectal adenoma and controls

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World Journal of Gastroenterology 2005年第33期11卷 5169-5173页

作者： Zong-Lin Deng da-Wen xie Roberd M Bostick xi-Jiang Miao You-Ling Gong Jin-Hui Zhang Michael J Wargovich Department of Epidemiology and Biostatistics University of South Carolina School of Public Health and South Carolina Cancer CenterColumbia SC 29203 United States Department of Epidemiology Rollins School of Public Health Emory University Atlanta GA 30322 United States Department of Computer Science and Engineering University of South Carolina Columbia SC 29201 United States Tumor Center West China Hospital Sichuan University Chengdu 610041 Sichuan Province China Department of Pathology University of South Carolina School of Medicine and South Carolina Cancer CenterColumbia SC 29203 United States

AIM: p53-Inducible ribonucleotide reductase small subunit 2 (p53R2) encodes a 351-amino-acid peptide, which catalyzes conversion of ribonucleoside diphosphates to the corresponding deoxyribonucleotides required for DNA replication and repair. A recent study reported that a point mutation (G/T) in the p53 binding sequence in a colon cancer cell line completely impaired p53R2 protein ***: We screened the p53R2 gene coding regions and a regulatory region which contains a p53 binding sequence in 100 patients with colorectal adenoma and 100 control subjects using PCR, cold SSCP, and direct DNA ***: Although we did not identify genetic variation in all nine exons, four regulatory-region variants were found,of which three were single nucleotide polymorphisms (SNPs) (nt 1 789 C/G, nt 1 928 A/G, 1 933 T/C), and one was 20 bp insertion which replaced a ATTTT between nt 1 831 and 1 835. Additionally, we determined the frequency of these p53R2 variants in a recently concluded case-control study of incident sporadic colorectal adenomas (163 cases and 210 controls).CONCLUSION: Although more detailed functional characterizations of these polymorphisms remain to be undertaken, these polymorphic sites may be useful for identifying alleles associated with mis-splicing, additional transcript factors and, more generally, in cancer-susceptibility association studies.

关键词： Genetic polymorphism Colorectal neoplasia p53R2, SSCP PCR-RFLP

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高速列车转向架舱内流场实车测试与数值模拟

交通运输工程学报 2015年第6期15卷 51-60页

作者：韩运动姚松陈大伟梁习锋中南大学交通运输工程学院中车青岛四方机车车辆股份有限公司

设计了一种高速列车转向架舱内流场状态测试装置。在无横风、横风速度为15m·s-1与端板角度分别为30°、45°、70°条件下对转向架舱内流场进行了数值模拟,并分析了裙板包覆对转向架舱内积雪形成的影响。试验结果表明:转向架舱内气流流... 详细信息

设计了一种高速列车转向架舱内流场状态测试装置。在无横风、横风速度为15m·s-1与端板角度分别为30°、45°、70°条件下对转向架舱内流场进行了数值模拟,并分析了裙板包覆对转向架舱内积雪形成的影响。试验结果表明:转向架舱内气流流动规律的实测结果与模拟结果相同,说明数值模拟可行;动气流由列车底部以及两侧裙板灌入转向架舱内,流经端板时产生流动分离现象,大部分气流由端板底部及两侧裙板后部排出;自头车往后,流经转向架舱内的气流速度逐渐减小,裙板处进气区域减小,裙板后部排气区域增大;雪粒大多由流经转向架舱底部的气流带入,然后在转向架流场影响下不断沉积而产生积雪;合理设置转向架舱端板角度可以减小冰雪在转向架舱内堆积的概率;包覆裙板并不能有效减少转向架舱内积雪,不建议采用。

关键词：高速列车转向架舱流场实车测试数值模拟

Experimental study on steam-water two-phase flow frictional pressure drops in helical coils

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Nuclear Science and Techniques 1997年第3期8卷 149-153页

作者： Bi Qin Cheng, Chen Ting Kuan, Tian Yong Sheng, Chen Xue Jun (National Laboratory of Multiphase Flow, xi’an Jiaotong University, xi’an710049)

ＥｘｐｅｒｉｍｅｎｔａｌｓｔｕｄｙｏｎｓｔｅａｍｗａｔｅｒｔｗｏｐｈａｓｅｆｌｏｗｆｒｉｃｔｉｏｎａｌｐｒｅｓｕｒｅｄｒｏｐｓｉｎｈｅｌｉｃａｌｃｏｉｌｓＢｉＱｉｎＣｈｅｎｇ，ＣｈｅｎＴｉｎｇＫｕａｎ，Ｔｉ... 详细信息

ＥｘｐｅｒｉｍｅｎｔａｌｓｔｕｄｙｏｎｓｔｅａｍｗａｔｅｒｔｗｏｐｈａｓｅｆｌｏｗｆｒｉｃｔｉｏｎａｌｐｒｅｓｕｒｅｄｒｏｐｓｉｎｈｅｌｉｃａｌｃｏｉｌｓＢｉＱｉｎＣｈｅｎｇ，ＣｈｅｎＴｉｎｇＫｕａｎ，ＴｉａｎＹｏｎｇＳｈｅｎｇ，Ｃｈｅｎ...

关键词：汽-水二相流部分压强螺形线圈中水滴

2.29-kV GaN-based double-channel Schottky barrier diodes on Si substrates with high VON uniformity

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Science China(Information Sciences) 2023年第6期66卷 309-310页

作者： Ren HUANG Weihang ZHANG Jincheng ZHANG Chunxu SU xi LIU Liyu FU Yue HAO Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices School of MicroelectronicsXidian University Wide Bandgap Semiconductor Innovation Center of Guangzhou Guangzhou Institute of TechnologyXidian University

The GaN on Si technology is attractive for power electronic systems owing to its low cost and large wafer size [1]. GaN Schottky barrier diodes(SBDs) on Si substrates have been extensively studied due to their superio...

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Biostratigraphy of a Paleocene-Eocene Foreland Basin boundary in southern Tibet

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Geoscience Frontiers 2010年第1期1卷 69-79页

作者： xiaoqiao Wan xi Wang Luba F. Jansa China University of Geosciences 29 Xueyuan Road Beijing 100083 China Department of Earth Sciences Dalhousie University Halifax N.S. Canada

This study of the Paleocene--Eocene boundary within a foreland basin of southern Tibet, which was dominated by a carbonate ramp depositional environment, documents more complex environmental conditions than can be derived from studies of the deep oceanic environment. Extinction rates for larger foraminiferal species in the Zongpu-1 Section apply to up to 46% of the larger foraminiferal taxa. The extinction rate in southern Tibet is similar to rates elsewhere in the world, but it shows that the Paleocene fauna disappeared stepwise through the Late Paleocene, with Eocene taxa appearing abruptly above the boundary. A foraminifera turnover was identified between Members 3 and 4 of the Zongpu Formation-from the Miscellanea--daviesina assemblage to an Orbitolites-Alveolina assemblage. The Paleocene and Eocene boundary is between the SBZ 4 and SBZ 5, where it is marked by the extinction of Miscellanea miscella and the first appearance of Alveolina ellipsodalis and a large number of Orbitolites. Chemostratigraphically, the δ^13C values from both the Zongpu-1 and Zongpu-2 Sections show three negative excursions in the transitional strata, one in Late Paleocene, one at the boundary, and one in the early Eocene. The second negative excursion of δ^13C, which is located at the P-E boundary, coincides with larger foraminifera overturn. These faunal changes and the observed δ^13C negative excursions provide new evidence on environmental changes across the Paleocene--Eocene boundary in Tibet.

关键词： Paleocene Eocene Foraminifera Carbon stable isotope Tibet

Green Light-Emitting Region-Regular Poly(9,9-Dihexylfluorene-co-Fluorenone) Prepared from Solvent-Free Oxidative Coupling Polymerization

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Wuhan University Journal of Natural Sciences 2007年第2期12卷 327-332页

作者： ZHAN Caimao CHEN Zhiyuan BAI Weibin YANG xi College of Chemistry and Molecular Sciences WuhanUniversity Wuhan 430072 Hubei China

Soluble green light-emitting poly（9,9-dihexylfluorene- co-fluorenone） was synthesized by solvent-free oxidative coupling polymerization of 9,9-dihexylfluorene in a facile one-step reaction. The polymers were characterized by FT-IR, ^1H NMR, ^13C NMR, UV-Vis and fluorescence spectroscopy. The region-regular structure of the polymer linking at 2, 7＇-position on the fluorene moieties was obtained. The FT-IR spectra of the polymers showed fluorenone vibration. The fluorescence spectra of the solid thin film of the polymers displayed green light-emitting, which was emitted from fluorenone moieties produced in the polymerization process.

关键词： solvent-free oxidative coupling polymerization poly(9, 9-dihexylfluorene-co-fluorenone) green light-emitting

Robust Symmetry Prediction with Multi-Modal Feature Fusion for Partial Shapes

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Intelligent Automation & Soft Computing 2023年第3期35卷 3099-3111页

作者： Junhua xi Kouquan Zheng Yifan Zhong Longjiang Li Zhiping Cai Jinjing Chen National University of Defense Technology ChangshaHunanChina Jiangxi University of Finance and Economics JiangxiChina Unit 78111 of Chinese People’s Liberation Army ChengduSichuanChina Sungkyunkwan University Korea

In geometry processing,symmetry research beneﬁts from global geo-metric features of complete shapes,but the shape of an object captured in real-world applications is often incomplete due to the limited sensor resolution,single viewpoint,and *** from the existing works predicting symmetry from the complete shape,we propose a learning approach for symmetry predic-tion based on a single RGB-D *** of directly predicting the symmetry from incomplete shapes,our method consists of two modules,i.e.,the multi-mod-al feature fusion module and the detection-by-reconstruction ***,we build a channel-transformer network(CTN)to extract cross-fusion features from the RGB-D as the multi-modal feature fusion module,which helps us aggregate features from the color and the depth ***,our self-reconstruction net-work based on a 3D variational auto-encoder(3D-VAE)takes the global geo-metric features as input,followed by a prediction symmetry network to detect the *** experiments are conducted on three public datasets:ShapeNet,YCB,and ScanNet,we demonstrate that our method can produce reliable and accurate results.

关键词： Symmetry prediction multi-modal feature fusion partial shapes