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基于收缩移动块的固定翼与飞行平台交会轨迹滚动时域规划

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高技术通讯 2024年第5期34卷 525-534页

作者：陈伟轩何德峰廖飞张啸天李书恒浙江工业大学信息工程学院杭州310023 中国空气动力研究所与发展中心空天技术研究所绵阳621000

针对一类固定翼与飞行平台组合系统的交会轨迹规划问题,提出一种基于收缩移动块的滚动时域规划算法。首先,建立固定翼无人机与飞行平台的交会动态模型,再将交会轨迹规划问题转化为一类以累加型能耗性能指标、固定终端时域、终端状态的... 详细信息

针对一类固定翼与飞行平台组合系统的交会轨迹规划问题,提出一种基于收缩移动块的滚动时域规划算法。首先,建立固定翼无人机与飞行平台的交会动态模型,再将交会轨迹规划问题转化为一类以累加型能耗性能指标、固定终端时域、终端状态的收缩时域滚动优化问题。其次,引入收缩移动块策略压缩轨迹规划问题的决策变量数,从而保证算法的实时性。在此基础上,建立算法的递推可行性和可转移性结果。最后,仿真比较结果验证了本文算法在交会过程节能、准时和实时计算等方面的优势。

关键词：固定翼无人机飞行平台模型预测控制(MPC) 移动收缩块轨迹规划

外语教学研究中问卷调查法的应用——如何进行问卷信度、效度和区分度检验

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辽宁师范大学学报（社会科学版） 2024年第3期47卷 114-120页

作者：林周婧李书恒薛婷历辽宁师范大学外国语学院辽宁大连116029

问卷调查法是中小学英语教师在教学研究中收集信息的常用手段,其质量关乎结论的可靠性,因此不仅在编制问卷时需遵循科学严谨的原则,还需借助统计学手段检验其质量。本研究依托“中学生英语阅读品格调查问卷”的试测数据,归纳了问卷结果... 详细信息

问卷调查法是中小学英语教师在教学研究中收集信息的常用手段,其质量关乎结论的可靠性,因此不仅在编制问卷时需遵循科学严谨的原则,还需借助统计学手段检验其质量。本研究依托“中学生英语阅读品格调查问卷”的试测数据,归纳了问卷结果的量化录入方法,介绍了编码手册的构成,解释了四种问卷数据类型的特点,详述了利用SPSS 23.0进行信度、效度和区分度分析的要求与操作方法。

关键词：问卷质量信度效度区分度问卷调查法外语教学研究

Geochronological Records of Oil-Gas Accumulations in the Permian Reservoirs of the Northeastern Ordos Basin

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Acta Geologica Sinica(English Edition) 2013年第6期87卷 1701-1711页

作者： CHEN Gang YANG Fu li shuheng ZHANG Huiruo HU Yanxu LEI Panpan State Key Laboratory of Continental Dynamics Department of Geology Northwest University Changqing Oilfield Company PetroChina Company Limited CNPC

Geochronology of oil-gas accumulation （OGA） is a challenging subject of petroleum geology in multi-cycle superimposed *** K-Ar dating of authigenic illite （AI） and fluid inclusion （FI） analysis combined with apatite fission track （AFT） thermal modeling,a case study of constraining the OGA times of the Permian reservoirs in northeast Ordos basin （NOB） has been conducted in this *** dating of the Permian oil-gas-bearing sandstone core-samples shows a wide time domain of 178-108 *** distribution of the AI ages presents 2-stage primary OGA processes in the Permian reservoirs,which developed in the time domains of 175-155 Ma and 145-115 Ma with 2-peak ages of 165 Ma and 130 Ma,*** FI temperature peaks of the samples and their projected ages on the AFT thermal path not only present two groups with a low and a high peak temperatures in ranges of 90-78℃ and 125-118℃,respectively corresponding to 2-stage primary OGA processes of 162-153 Ma and 140-128 Ma in the Permian reservoirs,but also appear a medium temperature group with the peak of 98℃ in agreement with a secondary OGA process of c.～30 Ma in the Upper Permian *** integrated analysis of the AI and FI ages and the tectono-thermal evolution reveals that the Permian reservoirs in the NOB experienced at least 2-stage primary OGA processes of 165-153 Ma and 140-128 Ma in agreement with the subsidence thermal process of the Mid-Early Jurassic and the tectono-thermal event of the Early ***,the Upper Permian reservoirs further experienced at least 1-stage secondary OGA process of c.～30 Ma in coincidence with a critical tectonic conversion between the slow and the rapid uplift processes from the Late Cretaceous to Neogene.

关键词： northeast Ordos basin (NOB) Permian sandstone reservoirs oil-gas accumulation (OGA) geochronology

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Q345板坯表面横裂纹热轧过程演变行为

中国冶金 2024年第1期34卷 44-52页

作者：王博莫超群李书恒孙立根韩毅华朱立光华北理工大学冶金与能源学院河北唐山063210 河北省高品质钢连铸工程技术研究中心河北唐山063210 河北科技大学材料科学与工程学院河北石家庄050018

在连铸生产过程中,由于化学元素、温度、机械应力等多方面因素影响,铸坯不可避免会产生表面横裂纹。轧制过程中,铸坯表面横裂纹会进一步放大影响到后续轧材的表面质量,甚至导致产品报废。为此,针对Q345钢表面横裂纹热轧过程演变行为展... 详细信息

在连铸生产过程中,由于化学元素、温度、机械应力等多方面因素影响,铸坯不可避免会产生表面横裂纹。轧制过程中,铸坯表面横裂纹会进一步放大影响到后续轧材的表面质量,甚至导致产品报废。为此,针对Q345钢表面横裂纹热轧过程演变行为展开研究,在铸坯表面预制“V”形裂纹进行实验室热轧试验,并建立相应轧制模型,通过试验验证模型正确性。采用现场板坯轧制工艺建立Q345钢表面不同宽度(1、2、3 mm)横裂纹轧制模型,分析不同宽度裂纹热轧过程演变特性。结果表明,宽度1 mm裂纹轧制过程出现了表面贴合的现象,而宽度2、3 mm裂纹两侧逐渐展开最后暴露到轧材表面;通过分析裂纹尺寸及高宽比变化可以发现,轧制过程不同宽度裂纹的展开宽度呈线性增加,轧制结束后,1、2、3 mm宽度裂纹展开宽度分别达到了30、32、34 mm,而裂纹深度在轧制初期减小明显,后几个道次减小量不大;不同宽度裂纹高宽比变化趋势与裂纹深度变化趋势相同,轧制初期变化量较大,轧制后几个道次高宽比趋近于0。研究结果可为优化轧制生产工艺提供理论参考。

关键词： Q345板坯表面横裂纹演变行为有限元模拟热轧

鄂尔多斯盆地长6和长8段致密油储层驱渗特征研究

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非常规油气 2024年第2期11卷 80-91页

作者：李书恒王永宏邓秀芹孙栋杨子清中国石油长庆油田分公司勘探开发研究院西安710018 低渗透油气田勘探开发国家工程实验室西安710018

鄂尔多斯盆地致密油储量丰富,主要富集在延长组三叠系长6和长8油层组,是目前增储上产的重要目标。为了推动该类油藏的规模效益开发,以深化储层特征与渗流规律认识为目的,在前期研究基础上,引入核磁共振、高压压汞、纳米CT扫描和高精度... 详细信息

鄂尔多斯盆地致密油储量丰富,主要富集在延长组三叠系长6和长8油层组,是目前增储上产的重要目标。为了推动该类油藏的规模效益开发,以深化储层特征与渗流规律认识为目的,在前期研究基础上,引入核磁共振、高压压汞、纳米CT扫描和高精度流体计量等新技术,系统开展了致密油储层微观孔隙结构、原油赋存状态以及水驱与渗吸动用规律研究。研究成果表明,致密油储层发育多尺度孔隙,孔隙结构以小孔-细喉型为主且连通性较好。物理模拟研究表明,原油在致密油储层的各类孔隙中均有分布,但大、中孔隙中原油的含量远高于小孔隙中的原油含量,且多以游离态存在,流动性好,是油田开发的主要对象。水驱油实验表明,致密油储层虽然存在启动压力梯度,但当驱替压力大于启动压力之后能够建立有效驱替系统,且随着驱替压力的增大水驱油效率会有所提高。核磁共振技术与水驱油实验或渗吸实验相结合,清楚地表明了不论采用水驱方式还是渗吸方式开发,致密油储层优先动用的都是较大孔隙中赋存的原油,小孔隙中赋存的原油动用难度较大。这些研究成果为探索更加有效的开发技术提供了依据。

关键词：致密油储层孔隙结构水驱油实验渗吸实验鄂尔多斯盆地

Geochemical Characteristics and Development Significances of Constant and Trace Elements from Coalbed Methane Co-Produced Water:A Case Study of the Shizhuangnan Block,the Southern Qinshui Basin

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Journal of Earth Science 2024年第1期35卷 51-61页

作者： Yang li shuheng Tang Jian Chen Songhang Zhang Zhaodong Xi Key Laboratory of Universities in Anhui Province for Prevention of Mine Geological Disasters Anhui University of Science and TechnologyHuainan 232001China School of Earth and Environment Anhui University of Science and TechnologyHuainan 232001China National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing 102249China School of Energy Resource China University of GeosciencesBeijing 100083China Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Enrichment Mechanism Ministry of EducationBeijing 100083China Key Laboratory of Strategy Evaluation for Shale Gas Ministry of Land and ResourcesBeijing 100083China

As an unconventional natural gas resource,coalbed methane(CBM)development releases a large amount of CBM wells co-produced *** characteristics of the co-produced water provide an essential foundation for the production dynamics of CBM reservoirs if the impacts of fracturing fluids and other aquifers can be *** the Shizhuangnan Block of the southern Qinshui Basin,constant and trace elements in CBM co-produced water from the wellheads were collected and determined,which is applied to assess water source,fracturing fluid effect,and CBM *** on principle component analysis and hierarchical clustering analysis,the water samples are divided into four *** suggests that different characteristics affected by water-rock interaction,reservoir environment,aquifer recharge,and hydraulic fracturing result in the various ratios of Na^(+)/Cl^(-),alkalinity(HCO_(3)^(-)+CO_(3)^(2-))/Cl^(-)and other specific ***,Cl^(-)is selected as a dividing line for complete fracturing fluid flow back,associated with organic-bound chlorine complexes in the original coal seam *** to constant elements,there is a significant correlation between li and Sr concentrations and CBM productivity,so templates regarding trace elements can be used to distinguish various sources of the co-produced water.

关键词： coalbad methane CBM co-produced water hydraulic fracturing Qinshui Basin

Modern geomorphological environment research during rapid urbanization in Shenzhen east coastal zone

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Journal of Geographical Sciences 2011年第2期21卷 372-384页

作者： GUO Wei li shuheng ZHU Dakui School of Human Settlements and Civil Engineering Xi'an Jiaotong University Xi'an 710049 China Department of Computer Sciences Xi'an Jiaotong University Xi'an 710049 China Department of Urban and Resources Sciences Northwest University Xi'an 710032 China Faculty of Environmental Sciences University of Waterloo Waterloo N2L3G1 Canada Key Laboratory of Coast & Island Development of Ministry of Education Nanjing University Nanjing 210093 China

The geomorphological environment is one of the most fundamental variables affecting the development of human society. The mission of geomorphological environment research is to explore the most basic environment and features of our Earth＇s surface morphology. The results can be applied to resource evaluation, environmental protection and reducing and preventing geological disasters. Thus, it can serve to help achieve sustainable development. This paper examines the Shenzhen east coastal zone as a case strongly influenced by urban expansion. We use modern geomorphological theory and methods, along with GIS and RS techniques, to reveal key characteristics of the geomorphological environment and landform classification. Furthermore, coastal ecosystem evaluation and regional resources sustainable utilization should be considered relative to the corresponding geomorphological environment. Based on this study, we conclude that modern geomorphological theory and methods, supported by ＂3S＂ techniques including GIS, RS and GPS, can play an important role in resolving the environment, resources and population problems as well as sustainable development challenges facing humankind at present.

关键词： Shenzhen geomorphological environment geographic information system remote sensing sustainable development

The 300th Mission of Long March Family Launched Successfully

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Aerospace China 2019年第1期20卷 55-56页

作者： li shuheng China Space News

A LM-3B carrier rocket at 00:28 Beijing time on March 10was launched from the Xichang Satellite Launch Center,launching the ChinaSat-6C into its preset orbit,marking the 300th launch of the Long March *** by CASC,the ... 详细信息

关键词： Mission Successfully carrier rockets

LM-7 Maiden Flight Achieved Success

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Aerospace China 2016年第2期17卷 58-61页

作者： li shuheng China Space News

At 20：00 Beijing time on June 25, China＇s new generation medium Launch vehicle LM-7 was launched from the Hainan Wenchang Spacecraft Launch Site,

关键词：航天器发射北京时间运载火箭场发射