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全球星摄动运动及摄动补偿运控策略研究

宇航学报 2010年第7期31卷 1756-1761页

作者：李恒年李济生焦文海西安卫星测控中心宇航动力学国家重点实验室西安710043 总装备部科技委北京100082 中国卫星导航工程中心北京100081

绕地卫星摄动运动是导致星座设计构型发散的主要因素,摄动补偿轨道控制是维持全球星座构型的基本策略。本文利用摄动分析法,通过建立星座轨道相对摄动运动方程,给出全球星轨道摄动规律和星座轨道整体飘移相对摄动运动规律,通过建立星座... 详细信息

绕地卫星摄动运动是导致星座设计构型发散的主要因素,摄动补偿轨道控制是维持全球星座构型的基本策略。本文利用摄动分析法,通过建立星座轨道相对摄动运动方程,给出全球星轨道摄动规律和星座轨道整体飘移相对摄动运动规律,通过建立星座轨道摄动补偿控制绝对和相对运动控制方程,比较了星座轨道绝对控制和相对控制策略的控制量需求,并探讨了两者的优缺点,为设计全球星座轨道和制定运控策略提供参考依据。

关键词：全球星座轨道摄动轨道控制星座保持

The Effect of Slab FC-Mold Technology on Fluctuations of Liquid Steel

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Journal of Iron and Steel Research International 2012年第S2期19卷 858-861页

作者： JIN Bai-gang LI Li-xun JIA dong-sheng HUANG Yu-ping LI Chao YANG Guo-jian WANG Qiang HE Ji-cheng Angang Steel Company Limited Anshan Iron and Steel Group Corporation Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern University

The application for FC-Mold(Flow Control Mold)technology is researched in Ansteel slab caster,and the fluctuations of liquid steel in different parameters are emphasis *** results show that the fluctuation of liquid steel can be decreased 50%by using FC-Mold,and the value is decreased from±5mm to±*** casting velocity can be increased 0.5m/min by using *** effect of FC-Mold is increased with increasing of *** FC-Mold can restrain the unstable liquid steel from velocity *** statistic application results for 610 strands show that the degraded ratio for automobile steel is decreased 6%.

关键词： slab electromagnetic brake flow control mold liquid steel fluctuation

Optimum design of flow distribution in quenching tank for heat treatment of A357 aluminum alloy large complicated thin-wall workpieces by CFD simulation and ANN approach

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Transactions of Nonferrous Metals Society of China 2013年第5期23卷 1442-1451页

作者：杨夏炜朱景川何东来忠红农智升刘勇哈尔滨工业大学金属精密热加工国家级重点实验室哈尔滨150001 哈尔滨工业大学材料科学与工程学院哈尔滨150001

Based on the computational fluid dynamics （CFD） method, a quenching tank with two agitator systems and two flow-equilibrating devices was selected to simulate flow distribution using Fluent software. A numerical example was used to testify the validity of the quenching tank model. In order to take tank parameters （agitation speed, position of directional flow baffle and coordinate position in quench zone） into account, an approach that combines the artificial neural network （ANN） with CFD method was developed to study the flow distribution in the quenching tank. The flow rate of the quenching medium shows a very good agreement between the ANN predicted results and the Fluent simulated data. Methods for the optimal design of the quenching tank can be used as technical support for industrial production.

关键词： A357 aluminum alloy computational fluid dynamics quenching tank flow distribution artificial neural network

Liver transplantation using organs from deceased organ donors: a single organ transplant center experience

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Hepatobiliary & Pancreatic Diseases International 2014年第4期13卷 409-415页

作者： Ming Han Zhi-Yong Guo Qiang Zhao Xiao-Ping Wang Xiao-Peng Yuan Xing-Yuan jiao Chun-Hua Yang dong-Ping Wang Wei-Qiang Ju Lin-Wei Wu An-Bin Hu Qiang Tai Yi Ma Xiao-Feng Zhu Xiao-Shun He Organ Transplant Center First Affiliated HospitalSun Yat-Sen University

BACKGROUND： In 2011, a pilot program for deceased organ donation was initiated in China. We describe the first successful series of liver transplants in the pilot ***： From July 2011 to August 2012, our center performed 26 liver transplants from a pool of 29 deceased donors. All organ donation and allograft procurement were conducted according to the national protocol. The clinical data of donors and recipients were collected and summarized ***： Among the 29 donors, 24 were China Category II donors（organ donation after cardiac death）, and five were China Category III donors（organ donation after brain death followed by cardiac death）. The recipients were mainly the patients with hepatocellular carcinoma. The one-year patient survival rate was 80.8% with a median follow-up of 422（2-696） days. Among the five mortalities during the follow-up,three died of tumor recurrence. In terms of post-transplant complications, 9 recipients（34.6%） experienced early allograft dysfunction, 1（3.8%） had non-anastomotic biliary stricture,and 1（3.8%） was complicated with hepatic arterial *** of these complications resulted in patient death. Notably,primary non-function was not observed in any of the ***： With careful donor selection, liver transplant from deceased donors can be performed safely and plays acritical role in overcoming the extreme organ shortage in China.

关键词： liver transplantation organ donors tissue and organ procurement

A Polyimide-Based Photocatalyst for Continuous Hydrogen Peroxide Production Using Air and Water under Solar Light

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CCS Chemistry 2022年第11期4卷 3482-3490页

作者： Yun-Xiao Lin Hua-Yi Kuang Shi-Nan Zhang Xiao-Le Zhang Guang-Yao Zhai Xiu Lin dong Xu Jinping Jia Xin-Hao Li Jie-sheng Chen School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240 School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240

Hydrogen peroxide(H_(2)O_(2))is a clean disinfectant,bleaching agent,and value-added fuel in various systems and is industrially produced through multistep energy-intensive hydrogenation/oxidation using H_(2)and O_(2).The exploitation of metal-free catalysts for alternative H_(2)O_(2)photoconversion is limited by their limited activity and selectivity,especially for the continuous H_(2)O_(2)production using only air,water,and solar ***,a cheap and robust polymer,poly(4,4′,4″-(1,3,5-triazine-2,4,6-triyl)triphenyl pyromellitimide)(PTTPI)was rationally synthesized by thermal structure-defect control under relatively low temperature(80-190℃),and the resulting metal-free material with a concisely refined band structure functioned as an efficient and ultra-stable photocatalyst for H_(2)O_(2)production over a wide pH *** PTTPI photocatalyst with an optimized defective degree(0.51)and moderate bandgap(2.3 eV)exhibited a H_(2)O_(2)production yield rate of 16.6μg h^(−1) mg_(cat)^(−1) and a high apparent quantumefficiency of 16.2%.By merging the well-designed PTTPI catalyst with the water transport path of natural cotton,a zero-emission and sunlightonly input system is constructed for continuous H_(2)O_(2)production from air and water in the natural *** design of the polyimide-based catalyst reveals a sustainable future toward efficient H_(2)O_(2)synthesis with sunlight-only energy input,enabling its implementation in other photocatalytic systems and on-site processing communities.

关键词： photocatalysis polyimide hydrogen peroxide band structure defective degree

镉胁迫对玉米幼苗抗氧化系统及光合作用的影响

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农业环境科学学报 2010年第2期29卷 211-215页

作者：黄辉李升郭娇丽天津师范大学化学与生命科学学院生物系天津300387

采用水培方法,在玉米幼苗进入三叶期后向培养液中加入不同浓度氯化镉(0、10-6、10-5、10-4mol·L-1),胁迫不同时间(5、10、15d)后对幼苗进行各项指标检测。结果表明,低浓度(10-6mol·L-1)及中浓度(10-5mol·L-1)镉胁迫对幼苗生长均有较... 详细信息

采用水培方法,在玉米幼苗进入三叶期后向培养液中加入不同浓度氯化镉(0、10-6、10-5、10-4mol·L-1),胁迫不同时间(5、10、15d)后对幼苗进行各项指标检测。结果表明,低浓度(10-6mol·L-1)及中浓度(10-5mol·L-1)镉胁迫对幼苗生长均有较强刺激作用,而中浓度胁迫对地上部分作用更明显;低浓度镉胁迫对根部及叶片抗氧化酶(SOD、POD、CAT及ASA-POD)活性影响较小,只是根部POD、ASA-POD活性明显升高,而中浓度胁迫对除SOD外其他抗氧化酶活性均有显著促进作用;MDA含量均未有显著升高,可见根部及叶片未受到氧化损伤;两种浓度胁迫下,Fv′/Fm′虽下降,净光合速率有所升高。高浓度镉(10-4mol·L-1)胁迫下幼苗生长几乎停止;根部SOD及CAT活性升高,而POD和ASA-POD被明显抑制,叶片中CAT、POD及ASA-POD活性显著升高;根部受到显著氧化损伤;各项光合参数(Fv/Fm、Fv′/Fm′和净光合速率)均显著降低。

关键词：镉玉米抗氧化酶丙二醛叶绿素荧光参数

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内部控制有效性认定辨析:环节、方式、范围

当代财经 2015年第1期 122-128页

作者：王东升吴秋生山西财经大学会计学院山西太原030031

内部控制有效性在认定环节上,设计有效应服务于执行有效;在认定方式上,基于"目标实现观"的"肯定式"认定比基于"重大缺陷观"的"否定式"认定更符合内部控制有效性的内涵;在认定范围上,内部控制目标应分为两个层次:合理保证层和促进实现层。

关键词：执行有效目标实现程度重大缺陷合理保证

Vertical-to-horizontal response spectral ratio for offshore ground motions:Analysis and simplified design equation

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Journal of Central South University 2017年第1期24卷 203-216页

作者：陈宝魁王东升李宏男孙治国李超 Faculty of Infrastructure Engineering Dalian University of Technology Road and Bridge Engineering Institute Dalian Maritime University

In order to study the differences in vertical component between onshore and offshore motions,the vertical-to-horizontal peak ground acceleration ratio(V/H PGA ratio) and vertical-to-horizontal response spectral ratio(V/H) were investigated using the ground motion recordings from the K-NET network and the seafloor earthquake measuring system(SEMS).The results indicate that the vertical component of offshore motions is lower than that of onshore *** V/H PGA ratio of acceleration time histories at offshore stations is about 50%of the ratio at onshore *** V/H for offshore ground motions is lower than that for onshore motions,especially for periods less than 0.8 ***,based on the results in statistical analysis for offshore recordings in the K-NET,the simplified V/H design equations for offshore motions in minor and moderate earthquakes are proposed for seismic analysis of offshore structures.

关键词： offshore ground motion vertical component simplified design equation vertical-to-horizontal response spectral ratio (V/H) vertical-to-horizontal peak ground acceleration ratio (V/H PGA ratio) K-NET network seafloor earthquake measuring system (SEMS)

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基于可视图法的多载波生命体征监测算法

云南大学学报（自然科学版） 2022年第6期44卷 1135-1145页

作者：刘影董升华辽宁工程技术大学电子与信息工程学院辽宁葫芦岛125105

针对传统的基于信道状态信息的生命体征监测算法使用单个子载波的幅度或相位信息进行监测时存在感知盲区的问题,提出一种基于可视图法的多载波生命信号检测方法.首先,分析相邻子载波之间的相关性,利用可视图法构建子载波间高感知性能的... 详细信息

针对传统的基于信道状态信息的生命体征监测算法使用单个子载波的幅度或相位信息进行监测时存在感知盲区的问题,提出一种基于可视图法的多载波生命信号检测方法.首先,分析相邻子载波之间的相关性,利用可视图法构建子载波间高感知性能的复杂网络,实现生命体征更精准的建模;然后,采用网络分析方法提取出相应的网络参数,并设计用于表示、构造多载波信息的网络特征信号;最后,采用离散小波变换提取出正常呼吸和心跳频率范围内的生命体征信息,分别采用峰值检测算法和快速傅里叶算法来估计呼吸频率和心率.实验结果表明,所提算法与传统的采用单个子载波的方法相比呼吸频率和心率的错误率分别降低了3.06%和2.26%,具有更好的检测性能.

关键词： CSI信道状态信息生命体征感知盲区可视图复杂网络