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Precise calculation of average strain and average strain rate considering roll elastic flattening

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Baosteel Technical Research 2015年第2期9卷 14-17页

作者： BAO Wenshuai WANG Wei zhang guomin Research Institute Baoshan Iron & Steel Co.Ltd.

Considering roll elastic flattening, new equations were proposed to calculate the average strain ε and average strain rate ε- in the hot strip rolling process. By comparing the proposed equations with currently used equations ,it was observed that the strain rate of thick strip and strain are not sensitive to roll elastic flattening. However,for thin strip, a noticeable calculated difference in the strain rate occurred when roll elastic flattening was considered.

关键词： hot strip rolling roll elastic flattening strain strain rate

Nonlinear Polarization Rotation Characteristic Phenomenon in a Bulk Semiconductor Optical Amplifier

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Optics and Photonics Journal 2013年第2期3卷 187-191页

作者： Xianghua Feng Jiarong Ji guomin zhang College of Optoelectronic Science and Engineering National University of Defense Technology Changsha China College of Science Information Engineering University Zhengzhou China

The phenomena of polarization rotation induced by self-modulation in semiconductor optical amplifier (SOA) are analyzed theoretically. The relationship between polarization parameters and gain as well as phase is obtained by the correlation parameter of ellipse polarization and SOA nonlinearity polarization rotation theory. The experiment employs polarizer drive by walking electromotor and power meter, the light power of 360 degree is measured. The transformation law of output polarization power components is found for obvious polarization rotation in the selected coordinate axes based on connection of polarization state in difference axes. Using this law make the manipulation easily on getting ideal polarization state. It can offer a fine method to realize all-optical switch and other logic elements in experiment. This work is of great significance for the applications of SOA nonlinear polarization rotation at high-speed all-optical signal processing and all-optical logic gate.

关键词： Strained Bulk SOA Nonlinear Polarization Rotation Phase Difference Polarization Azimuth

Impact of National Immunization Strategies on Vaccine- Preventable Diseases — China, 1950–2021

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China CDC weekly 2024年第16期6卷 339-343页

作者： Quanwei Song Yixing Li Lei Cao Lixin Hao Ning Wen Fuzhen Wang Chao Ma guomin zhang Hui Zheng Wenzhou Yu Zhijie An Zundong Yin Huaqing Wang National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases(NITFID) BeijingChina National Immunization Program Chinese Center for Disease Control and PreventionBeijingChina

What is already known about this topic?The incidences of vaccine-preventable diseases(VPDs)included in the Expanded Program on Immunization in China have decreased significantly in recent *** is added by this report?This study summarizes the national incidences of nine VPDs and the seroprevalence of hepatitis B surface antigen(HBsAg)under different immunization strategies from 1950 through 2021 in *** sharpest decreases in VPD incidence and under-5-year HBsAg seroprevalence occurred during the latest stage of the National Immunization *** decreases in VPD incidence were most prominent among children under five years of *** are the implications for public health practice?These findings provide valuable insights for vaccine value assessment and emphasize the importance of implementing immunization strategies in targeted populations.

关键词： vaccine diseases Impact

Effects of finish rolling tension on strip width

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Baosteel Technical Research 2009年第3期3卷 54-57页

作者： zhang Suoquan WANG Wei zhang guomin ZHU Tao Metallurgical Process Division Baosteel Research Institute Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China Shanghai Baosight Software Co. Ltd. Shanghai 201900 China

Based on the practical data of a strip hot rolling line and the flow patterns of the rolling process, the principle of the effect of the tension between mill stands on the strip width was analyzed. The results show that the tension between the upstream mill stands has a significant effect on strip width. The width change takes place in the deforming region between two mill stands, the effect of back tension is more than that of forward tension, and the width narrowing takes place in the biting position of the back slip region. Reasonable tension and its gradient setup are therefore significant factors in the accuracy of the strip width control.

关键词： finish rolling tension width spread

Thermal profile of work roll during strip hot rolling

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Baosteel Technical Research 2012年第4期6卷 41-43页

作者： zhang guomin ZHU Haihua CHEN Longfu Metallurgical Process Division Research InstituteBaoshan Iron & Steel Co.Ltd. Hot Rolling Plant Baosteel Stainless Steel Co.Ltd.

The thermal expansion of work rolls during hot strip rolling was modeled by a two-dimensional difference method. The calculation model was validated by comparison between the predictions to the measured results. With that model ,the effects of rolling process parameters such as the rolling plan, mill pacing ,coolant flow rate and stepped cooling on the roll thermal profile were investigated. The result shows that stepped cooling of work rolls can be used to control complicated flatness defects such as quarter buckles during hot strip rolling.

关键词： strip hot rolling roll thermal profile quarter buckle stepped cooling

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“是否存在有助于预报的地震前兆”的讨论

科学通报 2016年第18期61卷 1988-1994页

作者：刘杰张国民中国地震台网中心北京100045 中国地震局地震预测研究所北京100036

经过几十年地震预报探索实践,已发现了很多地震前兆异常,其中部分前兆还通过了优秀地震前兆标准的检验,并分析总结了前兆异常的群体特征.但用这些前兆异常,通过经验性统计方法进行地震预报成功率很低,其根本原因是地震孕育、发生的空间... 详细信息

经过几十年地震预报探索实践,已发现了很多地震前兆异常,其中部分前兆还通过了优秀地震前兆标准的检验,并分析总结了前兆异常的群体特征.但用这些前兆异常,通过经验性统计方法进行地震预报成功率很低,其根本原因是地震孕育、发生的空间尺度较大,前兆异常的挑选较为困难;地震复发周期较长,已积累的震例资料不足于研究地震孕育发生的规律;地震的孕震环境复杂,与周边的动力、构造环境密切相关,不同地震之间前兆异常差异较大;前兆观测分布在地球表面,只是地下应力、应变的间接反映,所获取的异常与地震前兆关系有待深入研究.在目前情况下,下一次地震完全按统计得到的共性特征演化明显是不可能的.地震前兆观测应从单点观测向直接观测地下应力、应变场过渡,地震预报从经验性统计预报向基于地球物理场动态观测的物理预报过渡.

关键词：地震前兆前兆的遴选与评价统计预报物理预报

高分辨率遥感图像港口检测的复合线索视觉注意模型

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遥感学报 2017年第2期21卷 300-309页

作者：毛玲张国敏海军工程大学电子工程学院武汉430033 海军工程大学装备经济管理系武汉430033

为提高高分辨率光学遥感图像港口自动检测的准确性,常需综合多类线索并进行复杂的特征提取、融合与分类推理,从而带来较高的计算复杂度。为此,仿生人类视觉注意机制,提出了一种复合线索视觉注意模型,综合利用高分辨率光学遥感图像港口... 详细信息

为提高高分辨率光学遥感图像港口自动检测的准确性,常需综合多类线索并进行复杂的特征提取、融合与分类推理,从而带来较高的计算复杂度。为此,仿生人类视觉注意机制,提出了一种复合线索视觉注意模型,综合利用高分辨率光学遥感图像港口多尺度底层特征和高层知识线索,实现了港口检测特征自然融合与综合分类推理。该方法在提高检测效果的同时较好地控制了计算量的增长,避免了复杂特征的大范围区域提取,采用多步快速算法降低了整个算法的计算复杂度,实现了计算资源受限条件下港口的快速定位与检测。同时,由于能将有限计算资源快速聚焦于最可能含有港口目标的区域,大大提高了目标检测方法响应的实时性。来自不同卫星的高分辨率光学遥感图像实验结果,验证了提出方法的有效性。

关键词：视觉注意高分辨率遥感图像港口检测混合线索

Accurate Location of the Yao'an Earthquake Sequence and the Yongsheng Earthquake Sequence

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Earthquake Research in China 2006年第1期20卷 37-49页

作者： Wang Xinling Liu Jie zhang guomin Zhao Cuiping Institute of Earthquake Science CEA Beijing 100036China China Earthquake Networks Center CEA Beijing 100036 China Institute of Geophysics CEABeijing 100081 China

The Yao’an M_S6.5 earthquake occurred on Jan. 15, 2000 and the Yongsheng M_S6.0 earthquake occurred on Oct. 27, 2001 in Yunnan Province, China. They are both located in the middle of the Dian block. Their epicenters are close to each other, the tectonic and strain characters of the earthquakes were similar, and there were many aftershocks after the two main shocks. In order to further study the spatial-temporal distributions and fault rupture characters of the main shocks and aftershocks, the latter are located using the Geiger earthquake location algorithm (Geiger) and the double difference earthquake location algorithm (DD) based on the seismic phase data of the two earthquake sequences. They were recorded by two Near Source Digital Seismic Networks (YNSSN and YSNSSN) deployed by the Yunnan Seismological Bureau (YNSB). Then, two main shock parameters were relocated using DD based on the data of larger magnitude aftershocks and the two main shocks that were recorded by the Kunming Regional Digital Seismic Network (KMSN). Combining the spatial-temporal distributions of the two earthquake sequences, the tectonic and strain characters of earthquakes, the rupture processes of the two aftershock sequences along faults are analyzed and discussed contrastively.

关键词： DD Earthquake sequence Fault Seismic energy

STUDIES ON BORON COMPOUNDS (Ⅱ)——SYNTHESIS AND PROPERTIES OF BORON CONTAINING BIS(π-ARENE)IRON(Ⅱ)COMPOUNDS

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Chemical Journal of Chinese Universities 1985年第2期 9-15页

作者： zhang Lun,Fang Xingin and zhang guomin(Department of Chemistry,Wuhan University,Wuhan)

Thirteen bis(π-arene)iron(Ⅱ) compounds were *** are [Ar FelB12H12 (Ar=C6H6 MeC6H5;EtC6H5;n-PrC6H5;t-Pr-C6H5 and These compounds have all been identified by elemental analysis and IR spectra,some of them by MS and H *** thermal behavior of these compounds has been investigated by DTA-TG method and IR spectroscopy,and their thermal stability was described.

关键词： AIC SYNTHESIS AND PROPERTIES OF BORON CONTAINING BIS STUDIES ON BORON COMPOUNDS ARENE)IRON COMPOUNDS