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Analysis of key technologies and development of integrated digital processing system for cast blasting design

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Journal of Central South University 2015年第3期22卷 1037-1044页

作者：丁小华李克民肖双双狐为民 School of Mines China University of Mining & Technology State Key Laboratory of Coal Resources and Safe Mining (CUMT) Department of Computer North China Institute Science of Technology

Casting blast can greatly reduce the stripping cost and improve the production capacity of opencast coal mines. Key technologies including high bench blasting, inclined hole, millisecond blasting, pre-splitting blasting and casting blast parameters determination which have influence on the effect of casting blast have been researched with the combination of the ballistic theory and experience in mines. The integrated digital processing system of casting blast was developed in order to simplify the design process of casting blast, improve working efficiency and veracity of design result and comprehensively adopt the software programming method and the theory of casting blast. This system has achieved five functions, namely, the 3D visualization graphics management, the intelligent management of geological information, the intelligent design of casting blast, the analysis and prediction of the blasting effect and the automatic output of the design results. Long-term application in opencast coal mines has shown that research results can not only reduce the specific explosive consumption and improve the blasting effect, but also have high value of popularization and application.

关键词： opencast coal mine cast blasting key technology digital processing system

Stepwise sedation for elderly patients with mild/moderate COPD during upper gastrointestinal endoscopy

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World Journal of Gastroenterology 2013年第29期19卷 4791-4798页

作者： Can-Xia Xu Xiong Chen Yan Jia ding-hua xiao Hui-Fang Zou Qin Guo Fen Wang xiao-Yan Wang Shou-Rong Shen Ling-Ling Tong Ke Cao xiao-Ming Liu Department of Gastroenterology Third Xiangya Hospital of Central South University Department of Health Statistics University of South China Department of Oncology Third Xiangya Hospital of Central South University

AIM: To investigate stepwise sedation for elderly patients with mild/moderate chronic obstructive pulmonary disease (COPD) during upper gastrointestinal (GI) endoscopy. METHODS: Eighty-six elderly patients with mild/moderate COPD and 82 elderly patients without COPD scheduled for upper GI endoscopy were randomly assigned to receive one of the following two sedation methods: stepwise sedation involving three-stage administration of propofol combined with midazolam [COPD with stepwise sedation (group Cs), and nonCOPD with stepwise sedation (group Ns)] or continuous sedation involving continuous administration of propofol combined with midazolam [COPD with continuous sedation (group Cc), and non-COPD with continuous sedation (group Nc)]. Saturation of peripheral oxygen (SpO 2 ), blood pressure, and pulse rate were monitored, and patient discomfort, adverse events, drugs dosage, and recovery time were recorded. RESULTS: All endoscopies were completed successfully. The occurrences of hypoxemia in groups Cs, Cc, Ns, and Nc were 4 (9.3%), 12 (27.9%), 3 (7.3%), and 5 (12.2%), respectively. The occurrence of hypoxemia in group Cs was significantly lower than that in group Cc (P < 0.05). The average decreases in value of SpO 2 , systolic blood pressure, and diastolic blood pressure in group Cs were significantly lower than those in group Cc. Additionally, propofol dosage and overall rate of adverse events in group Cs were lower than those in group Cc. Finally, the recovery time in group Cs was significantly shorter than that in group Cc, and that in group Ns was significantly shorter than that in group Nc (P < 0.001). CONCLUSION: The stepwise sedation method is effective and safer than the continuous sedation method for elderly patients with mild/moderate COPD during upper GI endoscopy.

关键词： Upper gastrointestinal endoscopy Adverse events Sedation Monitoring Chronic obstructive pulmonary disease

Physical simulation test of soil-rock mixture from synthetic transparent soil

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Journal of Central South University 2018年第12期25卷 3085-3097页

作者： ding xiao-hua ZHOU Wei LU Xiang GAO Yan School of Mines China University of Mining&TechnologyXuzhou221116China State Key Laboratory of Coal Resources and Safe Mining China University of Mining&TechnologyXuzhou221116China

The waste dump of open-pit coal mine is remade of soil-rock mixture under the action of gravity,dynamic load of transportation equipment and earthquake,*** using artificial synthetic transparent soil,the developing process and migration law for soil-rock mixture are observed in the remade *** mixture of fused quartz sand,liquid paraffin and n-tridecane is chosen as the material for synthetic transparent soil which is mixed with liquid paraffin and n-tridecane at a mass ratio of4.4at room temperature of17℃.Physical and mechanical properties of transparent soil are determined by physical test and compared with those in natural sandy *** results show that transparent soil and sandy soil have high similarity,in other words,transparent soil can be used for similar simulation experiments of soil-rock mixture.

关键词： transparent soil waste dump soil-rock mixture physical test

Detection of QTLs for Important Agronomic Traits and Analysis of Their Stabilities Using SSSLs in Rice

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Agricultural Sciences in China 2007年第7期6卷 769-778页

作者： ZHAO Fang-ming ZHU Hai-tao ding xiao-hua ZENG Rui-zhen ZHANG Ze-min LI Wen-tao ZHANG Gui-quan Guangdong Provincial Key Laboratory of Plant Molecular Breeding South China Agricultural University Guangzhou 510642 P.R.China

Single segment substitution lines （SSSLs） each with a single chromosome segment from a donor under the same genetic background as the recipient were developed in rice by advanced backcrossing and molecular marker-assisted selection. Using the SSSLs, the QTLs for the important agronomic traits in rice would be detected under different environmental conditions. Detection of the QTLs controlling 22 important traits in rice was done with 32 SSSLs by the randomized block design in 2-4 cropping seasons. 59 QTLs were detected and distributed on chromosomes 1, 2, 3, 4, 6, 7, 8, 10, and 11, of which 18 QTLs were detected more than twice. Only 30.5% of the QTLs were detected repeatedly in different cropping seasons. Most of the QTLs of important agronomic traits were of little additive effects and instability. The QTLs controlling the traits, such as grain weight, grain length, ratio of grain length to width, and heading date were relatively stable. The stable QTLs usually had larger additive effects and were less affected by environment. The QTLs for the important agronomic traits were detected using the SSSLs in rice with high resolution under different environmental conditions. The instability of the QTLs may be the basis of the variation of rice plants during growth and development. It would be the genetic basis for improving yield and quality in rice cultivars by farming methods.

关键词： rice single segment substitution line quantitative trait locus agronomic trait

Unconditional and Conditional QTL Mapping for Tiller Numbers at Various Stages with Single Segment Substitution Lines in Rice(Oryza sativa L.)

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Agricultural Sciences in China 2008年第3期7卷 257-265页

作者： ZHAO Fang-ming LIU Gui-fu ZHU Hai-tao ding xiao-hua ZENG Rui-zhen ZHANG Ze-min LI Wen-tao ZHANG Gui-quan Guangdong Key Laboratory of Plant Molecular Breeding South China Agricultural University Guangzhou 510642 P.R.China

Tiller is one of the most important agronomic traits which influences quantity and quality of effective panicles and finally influences yield in rice. It is important to understand ＂static＂ and ＂dynamic＂ information of the QTLs for tillers in rice. This work was the first time to simultaneously map unconditional and conditional QTLs for tiller numbers at various stages by using single segment substitution lines in rice. Fourteen QTLs for tiller number, distributing on the corresponding substitution segments of chromosomes 1, 2, 3, 4, 6, 7 and 8 were detected. Both the number and the effect of the QTLs for tiller number were various at different stages, from 6 to 9 in the number and from 1.49 to 3.49 in the effect, respectively. Tiller number QTLs expressed in a time order, mainly detected at three stages of 0-7 d, 14-21 d and 35-42 d after transplanting with 6 positive, 9 random and 6 negative expressing QTLs, respectively. Each of the QTLs expressed one time at least during the whole duration of rice. The tiller number at a specific stage was determined by sum of QTL effects estimated by the unconditional method, while the increasing or decreasing number in a given time interval was controlled by the total of QTL effects estimated by the conditional method. These results demonstrated that it is highly effective and accurate for mapping of the QTLs by using single segment substitution lines and the conditional analysis methodology.

关键词： single segment substitution line unconditional QTL mapping conditional QTL mapping tiller number rice

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作物数量性状基因图位克隆研究进展

植物遗传资源学报 2005年第4期6卷 464-468页

作者：丁效华华南农业大学/广东省植物分子育种重点实验室广州510642

对数量性状基因(QTL)的鉴定和克隆不仅有利于从分子水平上阐明作物重要农艺性状的形成机理,而且对于有效开展这些性状的分子育种,进一步提高作物增产潜力具有重要意义。近年来作物QTL图位克隆取得了重要突破,一批QTL被成功克隆,而模式... 详细信息

对数量性状基因(QTL)的鉴定和克隆不仅有利于从分子水平上阐明作物重要农艺性状的形成机理,而且对于有效开展这些性状的分子育种,进一步提高作物增产潜力具有重要意义。近年来作物QTL图位克隆取得了重要突破,一批QTL被成功克隆,而模式植物基因组研究的快速发展则为作物QTL图位克隆技术带来了新的策略和方法。本文就相关研究的主要进展和发展趋势进行了综述。

关键词：作物数量性状基因(QTL) 图位克隆基因组学

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基于Z变换匀速旋转运动模糊图像的快速恢复

光电工程 2006年第4期33卷 89-92,110页

作者：邸慧丁晓华于起峰国防科学技术大学航天与材料工程学院湖南长沙410073

从离散直观角度分析了由匀速旋转运动引起图像模糊的机理,通过Z变换方法,建立了由匀速旋转运动引起图像模糊的退化模型和恢复模型,并给出了快速算法。将运动模型扩展到任意形式的匀速运动,并给出了数学模型。通过计算机仿真实验,验证了... 详细信息

从离散直观角度分析了由匀速旋转运动引起图像模糊的机理,通过Z变换方法,建立了由匀速旋转运动引起图像模糊的退化模型和恢复模型,并给出了快速算法。将运动模型扩展到任意形式的匀速运动,并给出了数学模型。通过计算机仿真实验,验证了算法的正确性、有效性和快速性。本文推导的是理想模型,没有考虑噪声的影响。

关键词：匀速旋转运动模糊路径图像恢复 Z变换模糊图像

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数字化保护逻辑分析单元的研制

电力系统保护与控制 2009年第9期37卷 93-96页

作者：杨永标丁孝华周捷国电南瑞科技股份有限公司江苏南京210003

数字化保护逻辑分析单元包含保护逻辑记录单元和保护逻辑辅助分析单元。保护逻辑记录单元采用基于PowerPC8270的硬件平台和基于嵌入式Linux操作系统的软件平台,实时监视二次保护单元GOOSE网的虚遥信变位(即保护单元逻辑动作变位),启动... 详细信息

数字化保护逻辑分析单元包含保护逻辑记录单元和保护逻辑辅助分析单元。保护逻辑记录单元采用基于PowerPC8270的硬件平台和基于嵌入式Linux操作系统的软件平台,实时监视二次保护单元GOOSE网的虚遥信变位(即保护单元逻辑动作变位),启动波形文件记录。保护逻辑辅助分析单元提取和打开波形文件,通过分析波形时序图,再现故障时保护单元逻辑动作过程。

关键词：数字化保护逻辑分析单元 GOOSE 二次保护单元保护逻辑记录单元保护逻辑辅助分析单元

分布式虚拟同步发电机改进低电压穿越控制技术

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电机与控制学报 2020年第1期24卷 145-155页

作者：胡海林万晓凤丁小华余运俊江西理工大学电气工程与自动化学院江西赣州341000 南昌大学信息工程学院南昌330031

传统分布式虚拟同步发电机不具备低电压穿越能力,在分析电网短路故障时传统虚拟同步发电机的运行特性基础上,提出保留功率环的改进分布式虚拟同步发电机低电压穿越控制技术。改进控制技术给出了电网短路故障时功率指令值的计算方法,同... 详细信息

传统分布式虚拟同步发电机不具备低电压穿越能力,在分析电网短路故障时传统虚拟同步发电机的运行特性基础上,提出保留功率环的改进分布式虚拟同步发电机低电压穿越控制技术。改进控制技术给出了电网短路故障时功率指令值的计算方法,同时在无功功率控制环中引入PI调节器,并在同步旋转坐标下对输出电流进行分序控制,实现不对称故障时输出电流的三相平衡,最后通过引入虚拟阻抗对瞬时故障电流进行抑制。改进后的分布式虚拟同步发电机低电压穿越控制技术,保留功率控制环,不改变虚拟同步发电机机理,在故障发生和清除时,只需对功率指令值进行重新设定,无需切换控制策略,实现分布式虚拟同步发电机的低电压穿越。仿真及试验结果验证所提控制策略的正确性及有效性。

关键词：分布式虚拟同步发电机低压配电网低电压穿越虚拟阻抗电流分序控制无功电流注入