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韶关电厂8号机消除凝汽器真空低的技术改造

电力建设 2005年第5期26卷 17-19页

作者：何冬荣广东韶关发电厂广东省韶关市512132

韶关电厂8号机真空度低的主要原因是:管内壁结垢严重、冷却效果差;管内真空系统泄漏;汽轮机轴封系统调节不当;轴封系统结构不完善;外界循环冷却水温度的影响。为消除凝汽器真空度低,采取了以下改造措施:用高压水逐根清洗凝汽器铜管;为... 详细信息

韶关电厂8号机真空度低的主要原因是:管内壁结垢严重、冷却效果差;管内真空系统泄漏;汽轮机轴封系统调节不当;轴封系统结构不完善;外界循环冷却水温度的影响。为消除凝汽器真空度低,采取了以下改造措施:用高压水逐根清洗凝汽器铜管;为消除泄漏对凝汽器真空系统进行改造。凝汽器改造后,其排汽温度、端差下降、传热效果提高、真空度和经济效益提高。

关键词：凝汽器真空低技术改造

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浅析汕尾电厂锅炉微油点火改造原因及成效

价值工程 2011年第14期30卷 57-57页

作者：何冬荣广东红海湾发电有限公司汕尾516600

本文作者根据自己多年的实际工作经验,结合具体工程实例对汕尾电厂锅炉微油点火改造原因及成效相关方面问题进行分析,并提出了自己的看法和意见,供同行参考。

关键词：电厂锅炉微油点火改造

Numerical Simulation of Macrosegregation for an Fe-0.8 wt pct C Alloy

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Journal of Materials Science & Technology 2009年第4期25卷 561-568页

作者： dongrong Liu Dianzhong Li Baoguang Sang Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering Harbin University of Science and Technology Harbin 150040 China

Macrosegregation in Fe-0.8 wt pct C alloy solidifying with equiaxed morphology was numerically simulated. Based on a two-phase volumetric averaging approach, heat transfer, melt convection, composition distribution, nucleation and grain evolution on the system scale were described. A weak-coupling numerical procedure was designed to solve conservation equations. Simulations were conducted to study the effects of cooling rate and nuclei density on the macrosegregation pattern. The relative infliJence of thermal buoyancy- and solutal buoyancy-induced flows on macrosegregation was identified. Calculated results indicate that a higher cooling rate establishes a more homogeneous composition. More uniform solute distributions are formed with increasing nuclei density. In addition, it is noted that the direction of channel segregates depends on the relative strength of thermal and solutal buoyancy forces.

关键词： Macrosegregation Channel segregation Thermosolutal convection Fe-C alloy

A platform of digital brain using crowd power

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Frontiers of Information Technology & Electronic Engineering 2018年第1期19卷 78-90页

作者： dongrong XU Fei DAI Yue LU Columbia University & New York State Psychiatric Institute NY 10032 USA Shanghai Key Laboratory of Multidimensional Information Processing East China Normal University Shanghai 200062 China

A powerful platform of digital brain is proposed using crowd wisdom for brain research,based on the computational artificial intelligence model of synthesis reasoning and multi-source analogical *** design of the platform aims to make it a comprehensive brain database,a brain phantom generator,a brain knowledge base,and an intelligent assistant for research on neurological and psychiatric diseases and brain *** big data,crowd wisdom,and high performance computers may significantly enhance the capability of the *** achievements along this track are reported.

关键词： Artificial intelligence Digital brain Synthesis reasoning Multi-source analogical generating Crowd wisdom Deducing Neuroimaging

Numerical study of macrosegregation formation of ingot cast in normal sand mold and water-cooled sand mold

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Acta Metallurgica Sinica(English Letters) 2011年第1期24卷 54-64页

作者： dongrong LIU Xiuhong KANG Baoguanq SANG Dianzhong LI Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040 China

Formation of macrosegregation of 5 t steel ingots cast in sand molds with and without water-cooled copper tube is simulated by solving macroscopic mass, momentum, species and energy conservation equations with the consideration of shrinkage formation. Predicted macrosegregation pattern of the ingots shows a fair agreement with the experimental data. Both calculations and experiments reveal that some positive segregation patches are formed at the bottom of ingot. With the water-cooled copper tube inserted in the sand mold, the ingot cast has a less intensive macrosegregation. Mechanisms of macrosegregation formation are numerically analyzed. Explanations regarding the influences of fluid flow and temperature change upon the segregation formation are provided.

关键词： Macrosegregation Water-cooled mold Fe-C alloy Numericalsimulation

Evaluation of the Bioavailability of Metals in Sediment from the Southern Coastal Wetland of the Qiantang Estuary by Using Diffusive Gradients in Thin Films Technique

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Journal of Ocean University of China 2022年第2期21卷 375-387页

作者： FENG Weihua WANG Zhifu ZHU Wenzhuo ZheNG Fangqin ZHANG dongrong XU hengtao Key Laboratory of Engineering Oceanography Second Institute of OceanographyMNRHangzhou 310012China College of Marine Science&Technology Zhejiang Ocean UniversityZhoushan 316022China

Metal pollution has become an major issue governing the wetland ecosystem *** southern coastal wetland of the Qiangtang Estuary are facing unusual perturbation due to rapid development along the embayment in recent *** study evaluated the bioavailability of metals(Cu,Pb,Cd,Cr and Zn)in the sediment of the southern coastal wetland of the Qiangtang Es-tuary using diffusive gradients in thin films(DGT)techniques and compared with several methods based on total metal *** results showed that the contents of Cr,Pb,Cd and Cu in sediment,as detected using DGT,were considerably correlated with the exchangeable fraction and the content in Phragmites australis roots,while a weak correlation was observed for ***,DGT analysis could be used to evaluate the bioavailability and potential risk of Cr,Cd,Pb and Cu for *** indices,such as DGT concentration,bioaccumulation in ***,geoaccumulation index(Igeo)and potential ecological risk index(RI),revealed that Cd was a major potential ecological risk factor along the southern coast wetland of the Qiantang Estuary,especially in the upstream region,which is potentially more vulnerable to the anthropogenic pollution.

关键词： diffusive gradients in thin films estuarine wetland metal bioavailability

Analytical Models of on-Chip Hardware Trojan Detection Based on Radiated Emission Characteristics

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Chinese Journal of Electronics 2024年第2期33卷 385-392页

作者： Fan ZHANG dongrong ZHANG Qiang REN Aixin CheN Donglin SU School of Electronics and Information Engineering Beihang University Zhongguancun Laboratory The Research Institute for Frontier Science Beihang University

Since many third parties involved in integrated circuit(IC) manufacturing, hardware Trojans malicious implantation have become a threat to the IC industry. Therefore, varieties of reliable hardware Trojan detection methods are needed. Since electromagnetic radiation is an inherent phenomenon of electronic devices, there are significant differences in the electromagnetic radiated characteristics for circuits with different structures and operating states. In this paper, a novel hardware Trojan detection method is proposed, which considers the electromagnetic radiation differences caused by hardware Trojan implantation. Experiments of detecting hardware Trojan in field programmable gate arrays show that the proposed method can effectively distinguish the ICs with Trojan from the ones without Trojan by the radiated emission.

关键词： Electromagnetic radiation Propagation losses Hardware System-on-chip Registers Manufacturing Trojan horses

Determination of the controlled landing trajectory of Chang’E-1 satellite and the coordinate analysis of the landing point on the Moon

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Chinese Science Bulletin 2010年第13期55卷 1240-1245页

作者： LI JinLing GUO Li QIAN ZhiHan JIANG dongrong ZheNG WeiMin HONG XiaoYu Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China

Based on the tracking observations of radio ranges and VLBI delays of Chang’E-1 (CE-1) satellite during the controlled landing on the Moon on March 1, 2009, the landing trajectory and the coordinates of the landing point are determined by positioning analysis. It is shown that the landing epoch (the emission epoch of the last signal) of CE-1 satellite on the Moon was at UTC8h13m6.51s. The lunar longitude, latitude and surface height of the landing point in the lunar primary axes frame are respectively 52.2732°, 1.6440° and –3.56 km (the reference lunar radius is 1738 km). The uncertainties are 0.0040°, 0.0168° and 0.18 km. The corresponding uncertainty in the tangential direction of the lunar surface is 0.52 km and the three-dimensional (3D) positioning uncertainty is 0.55 km. It is accordingly deduced that even with the present technical specifications of the radio ranges and VLBI delays, the 1 km 3D positioning precision could be guaranteed for the lander in the second stage of China’s Lunar Explora- tion Project. Concerning the trace determination of the rover on the lunar surface, because only telemetry signal will be emitted, VLBI would be the sole tracking technique from the Earth. The application of the constraint of geocentric distance is shown to be helpful to improving the positioning precision. It is worthy to pay close attention to the applications of the same beam VLBI technique, the lunar topographic model and the on-board observations of the lander and rover to the position/trace determination of the rover.

关键词：卫星轨道控制嫦娥一号着陆点月球测定

Novel wreck salvaging method using curved rectangular pipe basing method:A case study of"Yangtze River EstuaryⅡ"ancient shipwreck salvage project

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Underground Space 2024年第5期18卷 97-113页

作者： Qianwei Zhuang Guofang Gong dongrong Zhou Chi Zhang Xin Huang Xiaodong Zhu Weihao Yuan Deng Li School of Mechanical Engineering Zhejiang UniversityHangzhou 310030China Shanghai Tunnel Engineering Co.Ltd. Shanghai 200137China Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai 200092China College of Civil Engineering and Architecture Xinjiang UniversityUrumqi 830047China Shanghai Salvage Company Shanghai 200090China

Shipwreck salvage is a risky,time-consuming,and expensive *** there are many sunken ships along coastlines and in the open seas,the salvage process of a sunken ship has rarely been *** integrated salvage of the"Yangtze River EstuaryⅡ"shipwreck used a novel method with 22 closely locked curved rectangular pipes to form a watertight base that wrapped the shipwreck *** basing was lifted out of the water using a powerful crane situated on an engineering *** the first time,the tunneling method was used in a shipwreck salvage project,significantly reducing the disturbance to the shipwreck and its stowage,thereby preserving the original state and integrity of the shipwreck to the greatest *** this study,the basic concepts of the salvage method and process are *** to critical issues in the new salvage method are provided,including jacking force prediction and major considerations for the structural design of the salvage *** design of the salvage system and salvage process of the"Yangtze River EstuaryⅡ"shipwreck are *** monitored jacking force,pipe deformation,and observed water-tightness verified that the proposed method was effective and *** possible application scenarios for the proposed method are presented at the end.

关键词： Pipe jacking Shipwreck salvage Yangtze River EstuaryⅡ Structural design